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Journal of Toxicology and Pharmacology

Open AccessResearch Article

Ameliorating Effect of Selenium against Deltamethrin Induced Hepato-Renal Dysfunction and Oxidative Stress to Pregnant Rats and Their Offspring

Sameeh A. Mansour*, Reham I. Mohamed and Amina R. AliEnvironmental Toxicology Research Unit (ETRU), Department of Pesticide Chemistry, National Research Centre, Tahrir Street, Dokki, Giza, Egypt

*Corresponding author: Sameeh A. Mansour, Email: [email protected]

Received: 20 December 2016; Accepted: 23 January 2017; Published: 31 January 2017

AbstractTwenty-Four female pregnant rats at gestation day 0 (GD 0)

were divided into equal six groups. Two groups were designated for deltamethrin (DEL) 1/10 LD50 and 1/100 LD50, other two groups for DEL + selenium, one group administered selenium (Se) and the sixth group served as control (water ad libitum). After parturition, day 0 of lactation (PND 0) and up to offspring weaning all the experimental groups were not exposed to any chemical. The doses of DEL (5.2 and 0.52 mg/kg b.wt.) and Se (6.66 µg/kg b.wt) were given orally by gavages for 21 days (gestation period). Compared to control results, animals treated with DEL recorded high elevation in the activity of ALT, AST, ALP, creatinine and MDA, as well as severe decline in the activity or levels of BuChE, urea, SOD and TAC. Alterations in these parameters were occurred in a dose-dependent manner, and dams were affected than their pups. Also, DEL produced noticeable histopathological changes in liver, kidney and ovary. Co-administration of Se in conjunction with DEL normalized the hepato-renal parameters, as well as the antioxidant enzymes especially at the low dose (1/100 LD50), and achieved improvement at the high dose (1/10 LD50). It was concluded that low doses of DEL can induce oxidative stress to pregnant rats and their offspring, but selenium can alleviate such hazards to a great extent.

Keywords: Pregnant rats; Offspring; Deltamethrin; Oxidative stress; Selenium; Amelioration

IntroductionLarge quantities of insecticides are used globally to combat

pests in agriculture and public health. Indeed, humans may expose to pesticides at all stages of their life including when the babies are still at mother’s womb and children are not adequately protected from the adverse effects of pesticides [1]. Epidemiological studies revealed an association between spontaneous abortions and fetal death after maternal exposure to pesticides [2]. Because of this concern, the use of many pesticides had been restricted and others were banned. In their place, pyrethroids have been emerged due to their high bioefficacy and lower toxicity in comparison with organochlorine (OC) and organophosphorous (OP) pesticides, as well as their photostability, high efficacy at low concentrations and low toxicity to birds and mammals [3].

Exposure to pyrethroids has been extensively documented in pregnant women, infants and children [4]. Pyrethroids increase embryonic resorption and fetal mortality [5] and fetotoxicity [6]. Maternal exposure to cypermethrin, for example, was found to affect the body and organs weights of offspring [7]. In rats exposed

to deltamethrin (DEL), there were decreases in the implantation sites, corpora lutea and recovered fetuses from uterine horns and increased incidence of pre- and post-implantation losses and early mortality rate [6].

DEL, a synthetic pyrethroid insecticide, is used extensively as an ectoparasiticide in crop protection and public health programs [8]. DEL administered during organogenesis reduced average weight of the live fetuses [9]. Compared with control rats, the DEL – treated animals showed incidence of early embryonic deaths and increase in placental weight [10]. Rats treated with DEL (2 mg/kg bw) from pregnancy through lactation showed reproductive hazards due to increasing the estrogenic potency of the target organs [11].

Women, during gestation may expose to low doses of DEL from different environmental sources, a matter which may affect the mother’s health and her progeny. DEL was reported to posses the ability of penetrating through the placental barrier producing a cardio-lessoning effects on the progeny [12]. It caused growth retardation, hypoplasia of the lungs and dilatation of the renal pelvis. Although DEL is relatively safe, its effects on the fetus should be considered in cases of using it on pregnant animals or in places where pregnant women live [10]. Subsequently, several investigations have been published on DEL toxicity to mammals (e.g., rats and mice) during gestation and effects on offspring. As examples, exposure of rats to DEL in utero and lactation may induce changes in physiology and reproductive behavior of male offspring at doses not causing maternal toxicity [13]. Also, DEL produced alterations in the ontogeny of xenobiotic metabolizing cytochrome P450 (CYP) isoforms in brain and liver of the offspring leading to increasing the activity of cytochrome P450 [14].

No toxicological symptoms were found in rats treated with ADI level of DEL during pregnancy. However, litter size was reduced and body weight gain of pups was less. Rats treated with 10 x ADI dose appeared weak and less active. Moreover, resorptions were observed in their uterus and cysts in the ovary. The results suggested that gestational exposure to ADI-DEL affect growth and viability of rat offspring and their development and behavior [15].

Induction of oxidative stress by the formation of reactive oxygen species (ROS) is one of the main mechanisms of pesticides action. These ROS are responsible of inducing oxidative stress in the tissues and chronic permanent damage [16]. At present, estimation of free radical formation and antioxidant’s defense has won great attention for the protection of cells against oxidative damage caused by different xenobiotics including pesticides [5], heavy metals and chemotherapeutic agents that may generate ROS [17]. Several substances including essential mineral elements; Zn [18,19] and Se [20,21] were used to alleviate toxic hazards of pesticides-induced oxidative stress in experimental animals.

To the best of our knowledge, there is no data on amelioration of deltamethrin- induced oxidative stress during pregnancy. However, there are many publications on normal male and female rats; e.g., Sakr and Al-Amoudi [22,23], El-Gerbed [24], Abdel-Daim et al. [25], Lamfon [26] and Al-Amoudi [27]. By other word, information regarding alleviation of deltamethrin induced toxicity to pregnant rats by an antioxidant such as selenium is lacking.

The present investigation was undertaken to assess the hepato-renal dysfunction and oxidative stress induced to female rats exposed during gestation to low doses of DEL and the indirect effects on their offspring. Moreover, the ameliorative effect of selenium co-administration was investigated for the first time.

Copyright © 2017 The Authors. Published by Scientific Open Access Journals LLC.

Citation: Mansour SA, Mohamed RI, Ali AR. Ameliorating Effect of Selenium against Deltamethrin Induced Hepato-Renal Dysfunction and Oxidative Stress to Pregnant Rats and Their Offspring. J Toxicol Pharmacol 2017; 1:002.

J Toxicol Pharmacol 2017; 1:002Volume 1, Issue 1Mansour et al.

Biochemical analyses The measurements of biochemical parameters were performed on

Shimadzu UV-VIS Recording 2401 PC (Japan) Spectrophotometer at the specified wavelengths and in accordance to the pamphlet instructions given by the manufacturers, and in light of the published methods. The activity of AST (EC.2.6.1.1) and ALT (EC.2.6.1.2) were determined according to the method described by Reitman and Frankel [31] at 546nm; expressing the enzyme’s activity in terms of U/L. ALP (EC 3.1.1) was measured in sera at 510 nm (U/L) according to Belfield and Goldberg [32]. Butyrtl cholinesterase (BuChE; EC 3.1.1.8) was measured at 405 nm and expressed as units per liter (U/L) using the method followed by Knedel and Bo¨ ttger [33]. Concentration of urea (in milligram per deciliter; mg/dl) was determined in sera at 550 nm using the method of Fawcett and Scott [34]. Creatinine was measurable at 495 nm according to Bartels and Bohmer [35] in terms of mg/dl. Lipid peroxidation (LPO) was determined in terms of malondialdehyde (MDA) which is a marker of LPO according to Satoh [36] at 534 nm; expressing concentration of MDA in terms of nmol/g tissue. The SOD (EC1.15.1.1) activity was measured at 560 nm and its activity was expressed in terms of ug/g tissue [37].

The determination of total antioxidant capacity (TAC) was based on the reaction of antioxidants in the sample with a defined amount of exogenously provided hydrogen peroxide (H2O2). The antioxidants in the sample eliminate a certain amount of the provided hydrogen peroxide. The residual H2O2 is determined colorimetrically by an enzymatic reaction which involves the conversion of 3,5-dichloro-2-hydroxy benzensulphonate to a colored product that measured at 505 nm according to Koracevic et al. [38]. Concentration of TAC in the sample was expressed in terms of mM/L.

Histological studies

Autopsy samples were taken from the liver, kidney and ovary from rats of different groups and fixed in 10% formalin saline for 24h. Washing was done in tap water and then dehydrated in ascending grades of alcohol. Specimens were cleared in xylene and embedded in paraffin bees at 56°C in hot air oven for 24 h. Paraffin blocks were prepared for sectioning at 4 microns thickness by slide microtome. The obtained tissue sections were collected on glass slides, deparaffinized and stained by hematoxylin and eosin (H&E) stain. Two slides were prepared for each animal; each slide contained two sections for each organ. Ten field areas for each section were selected and examined for histopathological changes under light microscope according to Banchroft et al. [39] at 40x magnification. The histopathology was carried out in the Pathology Department, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt. Tissue injury in the examined organs was scored in different ratings according to Brunt et al. [40].

Statistical analysis

The data were analyzed by using GraphPad Prism 5 Demo (www.graphpad.com/downloads/docs/Prism5Regressi on.pdf), and expressed as means ±S.E. Paired samples (t) test was used to compare the data of the control with those of treatments, where P < 0.05 and P < 0.01 were considered for significant and high significant differences, respectively. P > 0.05 means no significant difference.

ResultsSigns of toxicity and observationsAll animals were carefully observed during gestation and lactation

periods. Generally, the experimental animals showed normal behavior except signs of restless on the dams during gestation period. The number of pups per each female ranged between 6 and 14 of nearly 2:3 F: M sex ratio.

Materials and Methods Chemicals and reagents (Diagnostic Kits) A commercial formulation of deltamethrin (25% EC), product of

DuPont, was obtained from Kafr El-Zayat Pesticides & Chemicals Company, Egypt. Sodium selenite (Na2SeO3) was purchased from Mallinckrodt. Inc. (Paris, France). The diagnostic kits used in biochemical assays such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), butyrylcholinesterase (BuChE), urea and creatinine, as well as malondialdehyde (MDA), superoxide dismutase (SOD) and total antioxidant capacity (TAC), were purchased from Biodiagnostic Company, Dokki, Giza, Egypt.

Animals Twenty –Four female Wistar rats (Rattus norvegicus) and six

males, weighing 100-120g were obtained from the Animal Breeding House of the National Research Centre (NRC), Dokki, Cairo, Egypt. Both sexes were separately maintained in a controlled room of 12-hour light/dark cycle and 25 ± 2°C air temperature, and fed a standard pellet diet and tap water ad libitum for one week acclimatization period. Each four female rats and one male were placed in a clean plastic cage for mating. The presence of spermatozoa was checked in the vaginal smear every day in the morning. Mating was completed within 2-3 days. This day was connoted as gestation day 0 (GD 0). At that time, the male animals were removed and the pregnant females were received the assigned treatments up to 20-21 consecutive days. The day of parturition was considered day 0 of lactation, postnatal day 0 (PND 0). The offspring of each litter were counted, sexed and each litter was randomly reduced to 6 pups of equal number of sexes to maximize the lactation performance. The experimental work on rats was performed with the approval of the Animal Care & Experimental Committee, National Research Centre, Cairo, Egypt, and in accordance with the guidance for care and use of laboratory animals [28].

Experimental design During gestation period, the experimental rat dams received one of

the following treatments: G1: drinking water only (control group); G2: selenium (Se); G3: deltamethrin (1/100 LD50); G4: deltamethrin (1/10 LD50); G5: deltamethrin (1/100 LD50 + Se); and G6: deltamethrin (1/10 LD50 + Se). The insecticide deltamethrin and selenium were given orally by gavages. Deltamethrin was administered at two doses based on its oral LD50 for female rats (52.0 mg/kg b.wt.) obtained from Thomson [29]. Therefore, it was given at 5.2 mg/kg b.wt. (1/10 of LD50) and 0.52 mg/kg b.wt. (1/100 of LD50). The doses were adjusted on active ingredient (a.i.) content. Selenium was administered at a dose relative to the Upper Intake Levels [(ULs, 400 µg/person/day or 6.66 µg/kg b.wt)] for human [30]. During lactation period up to weaning (ca. 21 days), only water was permitted ad libitum to the six experimental groups.

Blood and organs samplingAt the end of weaning, final body weights were recorded and blood

samples were taken from the facial artery of each animal (dams and pups) under ether anaesthesia and added to non-heparinized centrifuge tubes to separate serum. This was performed by centrifugation at 3500 rpm (600g) for 10 min at 4°C using Hereaeus Labofuge 400R, Kendro Laboratory Products GmbH, Germany. The sera were kept in a deep freezer (-20°C) until analyzed. Then the animals were sacrificed by cervical dislocation, and the heart, spleen, liver, kidneys, testes or ovaries were removed and small pieces of organs were kept in 10% formalin for histopathological studies. Other pieces of liver (1g tissue + 1ml phosphate buffer, pH 7.4) were homogenized for 1min and centrifuged at 4500 rpm for 10 min at 4°C. The supernatant was withdrawn in clean tubes and kept in a deep freezer (-20°C) until analyzed for MDA and SOD.



Body and relative organs weightsThe average initial body weight was 174g for each female dam,

recorded 178g just after delivery (21 days), and then reached 206g at the weaning day (42 days). In between of the two stages, there was a drop in weights. Figure1 demonstrates fluctuation in bogy weights of the dams throughout the whole experimental duration, as exemplified by control, DEL (1/100 LD50); and DEL (1/10 LD50).

There were some variations in organs weights relative to body weights of dams in different groups. The liver for control group recorded 3.0% compared with 4.4% and 4.8%, respectively for DEL (1/100 LD50) and DEL (1/10 LD50); showing significant differences at P≤ 0.05 (Table 1). An opposite trend was obtained for relative weights of kidney and spleen where their values were lower than that of control groups. Except the selenium (Se) group (G2), all the other tested groups showed significant decrease (P≤ 0.05) in relative ovary values compared with control result. It seemed that the heart relative weights among the experimental groups were insignificantly different (Table 1).

Table 2 presents relative weights of organs from male and female pups whose mothers were treated with 2 doses of DEL. The male and female liver of control groups was 4.8% and 5.0%, respectively. The 2 doses of DEL, either with or without Se, gave higher values of significance at P≤ 0.01 and P≤ 0.05. As a general view, all the examined organs (e.g., kidney, heart, spleen, testis and ovary) from different treatments recorded significant decreases as compared with the control results with respect to relative weights of the above mentioned organs (Table 2).

Biochemical analysesResults of liver and kidney biochemical parameters and antioxidant

enzyme activities in rat dams treated with DEL, with and without Se co-administration, during gestation period are given in Table 3. As a general view, both control (G1) and Se (G2) values for the analyzed parameters had insignificant differences. The values of the other groups were more or less than those of control values at different levels of significance. Activities of butyryl cholinesterase (BuChE), urea, superoxide dismutase (SOD) and total antioxidant capacity (TAC) were lower, while those of the other estimated parameters (ALT, AST, ALP, creatinine and MDA) were higher than control values.

The ALT activity for the 2 DEL doses recorded 50.13 and 61.41 U/L, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of high significant difference (P≤ 0.01) than control value (24.57 U/L). Co-administration of Se in G5 (Se +1/100 LD50) improved the enzyme activity (40.59 U/L) to a great extend. Similar trend was noticed for the activity of AST and co-administration of Se in G5 (Se +1/100 LD50) normalized the enzyme activity (64.29 U/L), while it was relatively improved in G6 (Se +1/10 LD50) (77.03 U/L). The activity of ALP recorded 240.10 and 400.50 U/L, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of high significant difference (P≤ 0.01) than control value (90.61 U/L). Co-administration of Se in G5 (Se +1/10 LD50) normalized the enzyme activity (110.30 U/L), but it was relatively improved in G6 (230.10 U/L).

The activity of BuChE was declined severely in DEL treatments and recorded 2550.90 and 1410.70 U/L, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of high significant difference (P≤ 0.01) than control value (3270.10 U/L). Co-administration of Se in G6 (Se +1/10 LD50) didn’t much improve the enzyme activity (2610.10 U/L), while the activity of BuChE in G5 (3166.10 U/L) reached that of control value without significant difference.

The effect of different treatments on concentration of urea is presented in Table 3. Compared with control value (42.03 mg/dl), a significant (P≤ 0.05) and high significant (P≤ 0.01) decline was respectively obtained for DEL-1/100 LD50 and DEL-1/10 LD50. Co-administration of Se, either with the low or the high DEL doses normalized the concentration levels of urea in the serum of groups G5 and G6 (38.91 and 30.33 mg/dl, respectively). Concentration of serum creatinine recorded 1.33 and 1.80 mg/dl, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of high significant difference (P≤ 0.01) than control value (0.68 mg/dl). Co-administration of Se achieved little improvement in creatinine concentration level, especially for G5 (0.99 mg/dl).

The activity of malondialdehyde (MDA) for the 2 DEL doses recorded 5.60 and 6.90 nmol/g tissue, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of significant (P≤ 0.05) and high significant (P≤ 0.01) differences than control value (4.10 nmol/g tissue, respectively). Co-administration of Se in G6 (Se +1/10 LD50) improved the enzyme activity to some extend (5.10 nmol/g tissue), while its activity in G5 (3.90 nmol/g tissue) was insignificantly different than control value. The activity of SOD was declined severely in DEL treatments and recorded 229.00 and 111.03 ug/g tissue, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of significant differences at (P≤ 0.05) and (P≤ 0.01) than control value (354.9 ug/g tissue). Co-administration of Se in G6 improved the enzyme activity to some extend (250.09 ug/g tissue), while the activity of SOD in G5 (300.10 ug/g tissue) was normalized nearly. The activity of TAC was declined severely in DEL treatments and recorded 1.00 and 0.80 mM/L, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of high significant (P≤ 0.01) differences than control value (1.69 mM/L, respectively). Co-administration of Se, either in G5 (Se +1/100 LD50) or G6 (Se +1/10 LD50), normalized the enzyme activity (Table 3).

The levels of some biochemical parameters related to liver and kidney functions in serum of male and female pups whose mothers were treated with DEL, with and without Se co-administration, during gestation period are given in Table 4. Either in male or female pups, both control (G1) or Se (G2) values for the analyzed parameters had insignificant differences. The values of the other groups were more or less than those of control values at different levels of significance. Activities of butyryl cholinesterase (BuChE) and urea were lower, while those of the other estimated parameters (ALT, AST, ALP and creatinine) were higher than control values.

In male pups, the ALT activity for the 2 DEL doses recorded 51.90 and 60.08 U/L, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of high significant difference (P≤ 0.01) than control value (24.66 U/L). The activity of ALT was much improved in G5 (Se +1/100 LD50)

Figure 1: Fluctuation of body weights of female dams treated with deltamethrin during gestation period (3 weeks) followed with 3 weeks lactation without insecticidal treatments.0-1: Starting of gestation period; 0-2: Starting of lactation period.G1 = Control group; G3 = Deltamethrin (1/100 LD50); G4= deltamethrin (1/10 LD50).



Group Final Body weight (g) Relative organs weights (%)Liver Kidney Heart Spleen Ovary

G1 216.3 ± 8.3a 3.0 ± 0.07a 1.1 ± 0.0004a 0.69 ± 0.0006a 0.46 ± 0.0003a 2.4 ± 0.00025a

G2 200.7 ± 2.8a 3.1 ± 0.003a 1.4 ± 0.0006a 0.67 ± 0.0003a 0.45 ± 0.0003a 2.5 ± 0.0001a

G3 208.9 ± 3.8a 4..4 ± 0.0003b 0.9 ± 0.0002b 0.59 ± 0.0003a 0.41 ± 0.0005b 2.1 ± 0.0005b

G4 205.9 ± 4.8b 4.8 ± 0.002b 0.91 ± 0.0006b 0.51 ± 0.0001a 0.42 ± 0.0002b 2.0 ± 0.0005b

G5 202.7 ± 4.5b 2.9 ± 0.002a 0.98 ± 0.0004a 0.61 ± 0.0001a 0.44 ± 0.0001a 2.2 ± 0.0001b

G6 199.9 ± 11.5b 3.5 ± 0.002a 0.95 ± 0.0002a 0.60 ± 0.0003a 0.45 ± 0.0003a 2.1 ± 0.0006b

†Total experimental period = 42 days of which 21 days for lactation without insecticidal treatments.G1= control; G2= selenium; G3= deltamethrin (1/100 LD50); G4= deltamethrin (1/10 LD50); G5= deltamethrin (1/100 LD50 + selenium); G6= deltamethrin (1/10 LD50 + selenium).Statistical analysis:Values are means ± SE, n = 4. Compared with control values (G1) in each column:a = Non significant difference; b= Significant difference at (p ≤ 0.05); c= High significant difference at (P ≤ 0.01)

Table 1: Relative organs weights of female rat dams treated with deltamethrin during gestation period†.

Group Final* B.Wt. (g)

Relative organs weights (%)Liver Kidney Heart Spleen Testis Ovary

M F M F M F M F M F

G1 100.1 ± 1.1a

4.8 ± 0.003a

5.0 ± 0.002a

1.5 ± 0.001a

1.6 ± 0.003a

0.9 ± 0.03a

0.86 ± 0.3a

0.35 ± 0.4a

0.38 ± 0.33a

1.4 ± 0.005a

1.0 ± 0.003a

G2 50.1 ± 0.2c

5.0 ± 0.001a

5.1 ± 0.004a

1.45 ± 0.03a

1.5 ± 0.005a

0.89 ± 0.002a

0.91 ± 0.006a

0.36 ± 0.001a

0.37 ± 0.41a

1.6 ± 0.03a

0.9 ± 0.01a

G3 58.6 ± 0.1c

7.3 ± 0.003c

7.0 ± 0.01c

1.0 ± 0.005c

1.2 ± 0.009c

0.75 ± 0.01c

0.73 ± 0.007c

0.22 ± 0.003b

0.21 ± 0.076b

0.9 ± 0.001b

0.5 ± 0.002c

G4 55.0 ± 1.6c

8.0 ± 0.01c

9.0 ± 0.003c

1.2 ± 0.003c

1.3 ± 0.006c

0.70 ± 0.004c

0.71 ± 0.008c

0.16 ± 0.02c

0.18 ± 0.03c

0.85 ± 0.004b

0.6 ± 0.002c

G5 49.7 ± 0.1c

7.0 ± 0.001c

6.5 ± 0.006c

1.39 ± 0.06b

1.4 ± 0.008b

0.80 ± 0.05b

0.83 ± 0.03a

0.29 ± 0.007a

0.27 ± 0.001a

0.8 ± 0.01b

0.8 ± 0.05b

G6 60.1 ± 1.7c

6.1 ± 0.1b

6.0 ± 0.003b

1.33 ± 0.001c 1.4 ± 0.04b 0.85

± 0.006a0.84

± 0.008a0.23

± 0.05b0.22

± 0.03b0.95

± 0.007a0.84

± 0.009b

†Total experimental period = 42 days of which 21 days for lactation without insecticidal treatments.*Final body weight for pups without sex differentiation.G1= control; G2= selenium; G3= deltamethrin (1/100 LD50); G4= deltamethrin (1/10 LD50); G5= deltamethrin (1/100 LD50 + selenium); G6= deltamethrin (1/10 LD50 + selenium).Statistical analysis:Values are means ± SE, n = 4. Compared with control values (G1) in each column:a = Non significant difference; b= Significant difference at (p ≤ 0.05); c= High significant difference at (P ≤ 0.01)

Table 2: Relative organs weights of pups whose mothers were treated with deltamethrin during gestation period†.

Groups

Liver function enzymes Kidney function parameters Antioxidant enzymes

ALT (U/L) AST (U/L) ALP (U/L)BuChE (U/L) Urea (mg/dl) Creatinine

(mg/dl)MDA(nmol/g

tissue)SOD (ug/g

tissue)

TAC (mM/L)

62.03 ± 0.71a

90.61 ± 0.1a

3270.10 ± 0.03a G1 24.57

± 0.06a4.10

± 0.02a354.90

± 0.004a1.69

± 0.003a

G2 25.31 ± 0.058a

60.09 ± 0.09a

92.00 ± 0.6a

3269.80 ± 0.01a

40.03 ± 0.07a

0.70 ± 0.01a

4.50 ± 0.09a

333.01 ± 0.001a

1.55 ± 0.09a

G3 50.13 ± 0.57c

70.23 ± 0.03b

240.10 ± 0.07c

2550.90 ± 0.01c

29.04 ± 0.07b

1.33 ± 0.05c

5.60 ± 0.01b

229.00 ± 0.02b

1.00 ± 0.001c

G4 61.41 ± 0.02c

81.09 ± 0.27c

400.50 ± 0.06c

1410.70 ± 0.03c

20.07 ± 0.44c

1.80 ± 0.01c

6.90 ± 0.05c

111.03 ± 0.07c

0.80 ± 0.08c

G5 40.59 ± 0.91b

64.29 ± 0.08a

110.30 ± 0.09a

3166.10 ± 0.01a

38.91 ± 0.40a

0.99 ± 0.003b

3.90 ± 0.003a

300.10 ± 0.07a

1.56 ± 0.5a

G6 53.12 ± 0.28c

77.03 ± 0.80b

230.10 ± 0.02c

2610.10 ± 0.04b

30.33 ± 0.94a

1.09 ± 0.02c

5.10 ± 0.01b

250.09 ± 0.06b

1.57 ± 0.003a

†Total experimental period = 42 days of which 21 days for lactation without insecticidal treatments.G1= control; G2= selenium; G3= deltamethrin (1/100 LD50); G4= deltamethrin (1/10 LD50); G5= deltamethrin (1/100 LD50 + selenium); G6= deltamethrin (1/10 LD50 + selenium).Statistical analysis:Values are means ± SE, n = 4. Compared with control values (G1) in each column:a = Non significant difference; b= Significant difference at (p≤0.05); c= High significant difference at (P≤0.01)

Table 3: Some biochemical parameters of liver and kidney functions as well as antioxidant enzymes in rat dams treated with deltamethrin, with and without selenium co-administration, during gestation period†.



and equaled 40.20 U/L. Similar trend was obtained for female pups with little differences in the enzyme values. The low dose of DEL (1/100 LD50) induced elevation in AST activity accounting to 72.01 and 71.25 U/L, respectively for male and female pups. Compared with control values (61.01 and 60.09 U/L, respectively), there was a significant difference (P≤ 0.05) for female results. The high dose of DEL (1/10 LD50) induced high significant elevation (P≤ 0.01) in AST activity accounting to 81.20 and 80.10 U/L, respectively for male and female pups. Co-administration of Se in G5 (Se +1/100 LD50) normalized the AST activity for both male and female pups. In male pups, the ALP activity for the 2 DEL doses recorded 244.09 and 378.90 U/L, respectively for G3 (1/100 LD50) and G4 (1/10 LD50); values of high significant difference (P≤ 0.01) than control value (24.66 U/L). Co-administration of Se in G5 (Se +1/100 LD50) normalized the ALP activity. Similar trend was obtained for female pups except for G6 which showed ALP activity of 226.40 U/L; a high significant value compared with control value at P≤ 0.01.

Either in male or female pups the activity of BuChE were declined severely due to DEL treatments at the two tested doses. Fortunately, co-administration of Se in conjunction with low and high doses of

DEL normalized the activity of BuChE. For example, the activity of BuChE equaled 2998.0 and 2879.7 U/L, respectively for male and female pups of G6 (Se +1/10 LD50), compared with 3002.0 and 2973.3 U/L, respectively for control groups (G1).

The concentration of serum urea of male and female experimental groups recorded similar trend in both sexes. For example, the low dose of DEL (G3) caused significant decrease (P≤ 0.05) in urea concentrations accounting to 29.9 mg/dl and 31.34 mg/dl, respectively for male and female pups. On the other hand, the high dose of DEL (G4) caused high significant decrease (P≤ 0.01) in urea concentrations accounting to 20.11 mg/dl and 19.09 mg/dl, respectively for male and female pups. Fortunately, co-administration of Se in conjunction with low and high doses of DEL normalized the level of urea for both sexes. Compared with control results (0.70 and 0.68 mg/dl, respectively for male and female pups), creatinine concentrations recorded high significant elevation (P≤ 0.01) in DEL treatments (G3 and G4), and insignificant values with Se co-administrations (G5 and G6) (Table 4).

The activities of some antioxidants (MDA, SOD and TAC) in rat pups whose mothers were treated with deltamethrin during gestation, with and without Se supplementation, are given in Table 5.

Group Liver function enzymes Kidney function parametersALT(U/L)

AST(U/L)

ALP(U/L)

BuChE(U/L) Urea (mg/dl) Creatinine (mg/dl)

M F M F M F M F M F M F

G1 24.66 ± 0.3a

25.07 ± 0.6a

61.01 ± 0.003a

60.09 ± 0.01a

91.05 ± 0.005a

90.21 ± 0.01a

3002 ± 0.001a

2973.3 ± 0.033a

40.09 ± 0.1a

42.33 ± 0.005a

0.70 ± 0.1a

0.68 ± 0.003a

G2 23.95 ± 0.1a

25.01 ± 0.05a

59.07 ± 0.001a

61.03 ± 0.09a

91.8 ± 0.03a

93.9 ± 0.06a

2991 ± 0.07a

2809.1 ± 0.015a

40.5 ± 0.01a

41.3 ± 0.17a

0.70 ± 0.05a

0.72 ± 0.03a

G3 51.9 ± 0.31c

50.13 ± 0.57c

72.01 ± 0.73a

71.25 ± 0.31b

244.09 ± 0.10c

250.5 ± 0.09c

2105.5 ± 0.07c

2230.3 ± 0.05c

29.9 ± 0.001b

31.34 ± 0.03b

1.33 ± 0.005c

1.51 ± 0.6c

G4 60.08 ± 0.05c

61.41 ± 0.02c

81.2 ± 0.003c

80.1 ± 0.07c

378.9 ± 0.005c

390.5 ± 0.36c

1119.1 ± 0.09c

1300.1 ± 0.3c

20.11 ± 0.006c

19.09 ± 0.4c

1.81 ± 0.7c

1.73 ± 0.03c

G5 40.2 ± 0.005b

40.59 ± 0.91b

60.33 ± 0.04a

61.21 ± 0.01a

100.09 ± 0.07a

125.6 ± 0.06a

2955.6 ± 0.01a

3006.8 ± 0.03a

37.66 ± 0.9a

35.01 ± 0.33a

0.79 ± 0.009a

0.73 ± 0.07a

G6 55.01 ± 0.32c

53.12 ± 0.28c

77.5 ± 0.005b

75.23 ± 0.82b

201.7 ± 0.33b

226.4 ± 0.03c

2998 ± 0.007a

2879.7 ± 0.5a

33.7 ± 0.02a

31.03 ± 0.04a

0.90 ± 0.001a

0.83 ± 0.5a


Table 4: Some biochemical parameters of liver and kidney functions in rat pups whose mothers were treated with deltamethrin, with and without selenium co-administration, during gestation period†.

GroupAntioxidant enzyme activities

MDA (nmol/g.tissue) SOD (ug/g.tissue) TAC (mM/L)M F M F M F

G1 3.9 ± 0.1a 4.03 ± 0.005a 350.01 ± 0.03a 344.33 ± 0.11a 1.71 ± 0.3a 1.88 ± 0.009a

G2 4.1 ± 0.03a 4.2 ± 0.5a 359.09 ± 0.01a 342.25 ± 0.003a 1.76 ± 0.07a 1.67 ± 0.01a

G3 4.9 ± 0.003b 5.0 ± 0.001b 249.07 ± 0.08b 265.09 ± 0.007b 1.23 ± 0.05c 1.01 ± 0.11c

G4 5.7 ± 0.01c 6.03 ± 0.33c 120.01 ± 0.01c 133.9 ± 0.004c 0.93 ± 0.33c 0.87 ± 0.03c

G5 4.2 ± 0.5a 4.5 ± 0.003a 320.7 ± 0.5a 347.1 ± 0.001a 1.57 ± 0.9a 1.86 ± 0.005a

G6 4.0 ± 0.01a 4.1 ± 0.002a 290.1 ± 0.7a 301.2 ± 0.03a 1.59 ± 0.7a 1.53 ± 0.023a


Table 5: Antioxidant enzyme activities in rat pups whose mothers were treated with deltamethrin, with and without selenium co-administration, during gestation period†.



Lipid peroxidation (LPO) in terms of malondialdehyde (MDA) in liver tissues of male and female pups recorded 3.9 and 4.03 nmol/g tissue, respectively in control groups (Table 5). Either in male or female pups, the low dose of DEL, G3 (1/100 LD50), induced significant elevation (P≤ 0.05) in MDA activity (4.9 and 5.0 nmol/g tissue, respectively), while the high dose of DEL, G4 (1/10 LD50) caused high significant increase (P≤ 0.01) accounting to 5.7 and 6.03 nmol/g tissue, respectively. Interestingly, co-administration of Se in G5 (Se + 1/100 LD50) or G6 (Se + 1/10 LD50) has retained MDA activity to its normal level without significant differences with control results. These results were obtained for male and female animals (Table 5). Activity of superoxide dismutase (SOD) in liver tissues of male and female pups recorded 350.01 and 344.33 ug/g tissue, respectively in control groups (Table 5). Either in male or female pups, the low dose of DEL, G3 (1/100 LD50), induced significant decrease (P≤ 0.05) in SOD activity (249.07 and 265.09 ug/g tissue, respectively), while the high dose of DEL, G4 (1/10 LD50) caused high significant decline (P≤ 0.01) accounting to 120.01 and 133.90 ug/g tissue, respectively. Interestingly, co-administration of Se in G5 or G6 has retained SOD activity to its normal level without significant differences with control results. These results were obtained for male and female animals (Table 5). Activity of total antioxidant capacity (TAC) in serum of male and female pups recorded 1.71 and 1.88 mM/L, respectively in control groups (Table 5). Either in male or female pups, both the

low and the high doses of DEL (G3 and G4) induced high significant decreases (P≤ 0.01) in TAC activity. Fortunately, co-administration of Se in G5 or G6 has retained TAC activity to its normal level without significant differences with control results. These results were obtained for male and female animals (Table 5).

Histological examination

Microscopical examinations for histological sections from liver, kidney and ovary from dams treated with the insecticide DEL, with and without selenium co-administration, are illustrated in Fig. 2 and presented in Table 6 based on scoring severity of injury in different organs.

The liver sections of control dams (G1) and Se (G2) showed normal histological structure of hepatic lobule from central vein (CV) and normal hepatocytes (H). Light dilatation and congestion in the central vein (CV)] in the section of G3 (1/100 LD50), but such symptoms were severe in G4 (1/10 LD50). Co-administration of Se in G5 (1/100 LD50 +Se) improved the histological structure better than in G6 (1/10 LD50) (H&E stain 40x).

The kidney sections of control dams (G1) and Se (G2) showed normal histological structure of the glomeruli (g) and tubules (t) at the cortex. In the higher dose of DEL the tubules at the cortex showed degenerative

Histopathological changesG3: DEL (1/100

LD50) G4: DEL (1/10 LD50) G5: DEL (1/100 LD50)+ Se

G6: DEL (1/10 LD50)+ Se

Dams Pups Dams Pups Dams Pups Dams Pups

LIVER- Dilation and congestion in the portal vein(pv)

-Inflammatory cells surrounding the bile ducts (bd) in between the hepatocytes

-Focal haemorrhage (h) in the hepatic parenchyma

2

1

0

2

2

1

3

2

0

3

2

2

1

1

0

0

0

1

2

1

0

0

1

2

KIDNEY- Dilation and congestion with swelling in the lining epithelial cells of the tubules (t)

-Congestion of the blood vessels (pv) at the cortex

-Vacuolization in the endothelial cells lining the glumerular tufts (g)

-Focal haemorrhage (h) at the corticomedullary portion

2

2

2

0

1

0

0

2

3

3

3

0

1

0

0

3

1

0

1

0

0

0

0

1

2

0

2

0

0

0

0

2

OVARY- Congestion in the stromal blood vessels(v) at different stages of follicular maturation (f)

-Different stages of follicular maturation (f) with corpus luteum (cl)

2

2

--

--

3

3

--

--

1

1

--

--

2

2

--

--Degree of changes: (0) = no change; (1) = mild change (e.g., <25% of cells showing damage);(2) = moderate change (e.g., 25–50% cell damage); and (3) = severe change (e.g., >50% cell damage). --: not included.

Table 6: Histopathologic changes based on scoring severity of injury in different organs from rat dams and their pups following exposure to deltamethrin with and without selenium during gestation.



change in the lining epithelium associated with vacuolization in the endothelial cells lining the glomerular tufts (g). The lower DEL dose caused light dilatation and congestion with swelling in the lining epithelial cells of the tubules (t) associated with mild congestion in the blood vessels (pv) at the cortex. Vacuolization in the endothelial cells lining the glomerular tufts (g) was less pronounced in G5 (1/100 LD50 +Se) compared with G6 (1/10 LD50 +Se) (H&E stain 40x).

The ovary sections of control dams (G1) and Se (G2) showed normal histological structure of the oocytes and follicles in different stages with corpus luteum. Severe congestion in the stromal blood vessels (v) and different stages of follicular maturation (f) were seen in G4 (1/10 LD50) and G5(1/100 LD50), but at different severity of lesions. Different stages of follicular maturation (f) with corpus luteum (cl) were manifested in G6 (1/10 LD50 +Se). G5 (1/100 LD50 +Se) showed mild follicular maturation (f) and light congestion in the stromal medullary blood vessels (H&E stain 40x).

Microscopical examinations for histological sections of liver and kidney from the rat pups, without sex differentiation, are illustrated in Figure 3 and presented in Table 6 based on scoring severity of injury in different organs.

Liver sections of G1 and G2 showed normal histological structure of hepatic lobule from central vein (cv) and normal hepatocytes (h). In G3 (1/100 LD50), mild dilatation and congestion were detected in portal vein (pv) while the hepatocytes showed degenerative change (m). These symptoms were severe in G4 (1/10 LD50). In G5 (1/100 LD50 +Se), focal haemorrhage (h) was noticed in the hepatic parenchyma. In G6 (1/10 LD50 +Se), few inflammatory cells infiltration was detected in the portal area (pv) and degenerative change in the hepatocytes (m) (H&E stain 40x).

Kidney sections of G1 and G2 showed normal histological structure of the glomeruli (g) and tubules (t) at the cortex. There was focal

Liver

G1 G4 G6 (a & b) Kidney

G1 G4 G6 Ovary

G1 G4 G6

Figure 2: Sections of liver, kidney and ovary from rat dams treated with deltamethrin, with and without selenium co-administration.The liver sections of control dams (G1) or Se treatment (G2) showing normal histological structure of hepatic lobule from central vein (CV) and normal hepatocytes (H). In G4 (1/10 LD50), severe dilatation and congestion were noticed in the portal vein (PV) associated with inflammatory cells surrounding the bile ducts (bd) in between the hepatocytes. [N.B: G3 (1/100 LD50): resembled G4 but with light dilatation and congestion in the central vein (CV)]. In G6 (1/10 LD50), severe dilatation and congestion were seen in the central vein (CV) and poretal vein (PV) (a & b). [N.B.: G5 (1/100 LD50 +Se) resembled G6 but with light dilatation and congestion in the central vein (CV) only] (H&E stain 40x).The kidney sections of control dams (G1) or Se treatment (G2) showing normal histological structure of the glomeruli (g) and tubules (t) at the cortex. G4: showing severe dilatation and congestion with swelling in the lining epithelial cells of the tubules (t) associated with mild congestion in the blood vessels (pv) at the cortex. The tubules at the cortex showed degenerative change in the lining epithelium associated with vacuolization in the endothelial cells lining the glomerular tufts (g). [N.B: G3 (1/100 LD50): resembled G4 but with light dilatation and congestion]. G6: the corticomedullary portion showed focal haemorrhage in between the degenerated tubules and vacuolization in the endothelial cells lining the glomerular tufts (g). [N.B.: G5 (1/100 LD50 +Se) resembled G6 but with mild vacuolization in the endothelial cells lining the glomerular tufts (g) only] (H&E stain 40x).The ovary sections of control dams (G1) or Se treatment (G2) showing normal histological structure of the oocytes and follicles in different stages with corpus luteum. G4: severe congestion in the stromal blood vessels (v) and different stages of follicular maturation (f). [N.B: G3 (1/100 LD50): nearly resembled G4 with respect to congestion in the stromal blood vessels (v). G6: showing different stages of follicular maturation (f) with corpus luteum (cl). [N.B.: G5 (1/100 LD50 +Se) showed mild follicular maturation (f) and congestion in the stromal medullary blood vessels (H&E stain 40x).



haemorrhage (h) at the corticomedullary portion in sections of G3 (1/100 LD50) and G4 (1/10 LD50), but was severe in the high dose of DEL. In G5 (1/100 LD50+ Se), there was focal haemorrhage in between the tubules and mild dilatation and congestion in the portal vein (pv). In G6 (1/10 LD50 + Se), the tubules showed degeneration (d) in the lining epithelium associated with mild congestion in the blood vessels (v) at the cortex (H&E stain 40x).

DiscussionIn toxicological studies, evaluation of organ toxicity is an important

criterion. Generally, increase or decrease of organs weights than normal may be considered as a sign of toxicity. Deltamethrin (DEL) has poor feed conversion efficiency, so it may affect body and organs weights [41]. As our experiment was conducted throughout gestation and lactation periods, the body weights of dams did not significantly deferred after delivery or after weaning; neither in control nor in DEL treatments (Figure 1). However, the relative weights of liver of dams in DEL treatments recorded significant elevation, while kidney, spleen and ovary showed significant decrease in comparison with control treatments (Table 1). Similar findings were nearly obtained for the pups (Table 2). Our results are supported by previous investigations reporting a decline in body and organ weights due to administration of DEL and other pyrethroids in experimental animals [41,42].

Most toxic chemicals are metabolized in liver or excreted out through kidneys and these processes may alter the function of these organs. Hepatocytes contain a large amount of enzymes such as AST and ALT. These enzymes release into plasma as a result of liver damage. Therefore, the measurement of these enzymes in plasma is used to evaluate and identify liver damage [43]. Alkaline phosphatases (ALPs) are a group of enzymes found primarily in the liver (isoenzyme ALP-1) and bone (isoenzyme ALP-2). Also, there are small amounts produced by cells lining the intestines (isoenzyme ALP-3), the placenta, and the kidney (in the proximal convoluted tubules). Thus, the measured in the blood expresses the total amount of ALP released from these tissues into the blood. The primary importance of measuring ALP is to check the possibility of bone or liver diseases [43].

The results of the present investigation indicate that leakage of cellular enzymes was generally higher in the high dose of DEL than in the low dose (Table 3 and 4). According to Salih [44], the enzyme leakage exhibited good correlation with cellular damage caused by toxic substances. This was frequently accompanied with increasing permeability of cell membranes. Moreover, increased levels of ALT, AST, and ALP enzymes indicate destruction of liver cells and leakage of these enzymes from liver cytosol into the blood stream [45]. Our findings coincide with Lamfon [26] who reported that albino rats treated with 1/10 LD50 of DEL showed significant increase in serum levels of ALT, AST and ALP compared with control animals.

Deltamethrin causes membrane lipid peroxidation (LPO) and disturbs the function of cell membrane. Therefore, it changes permeability of membrane and affect the function of liver’s antioxidant enzymes. Subsequently, the transfer of ions and various materials, as well as the transportation of chemical messenger will be disrupted by membrane receptors. This will cause the penetration of liver’s antioxidant enzymes from liver’s cytoplasm into blood flow [46].

Cholinesterase (ChE), or pseudocholinesterase, is synthesized mainly in hepatocytes and secreted into the blood stream. Its activity is declined in liver dysfunction due to reduced synthesis in contrast to other serum enzymes of liver function whose activities increase as a result of increased release from their cellular sources following damage of cell membrane [47]. In this respect, changes in ChE activity reflect the changes in hepatocellular functions and have been regarded as sensitive indicators of the diminished synthetic capacity of the

hepatic parenchyma [48]. In the present study, the decline of BuChE seemed to occur in a dose- dependent manner with respect to the tested doses of DEL (Table 3 and 4).

In experimental animals, kidney is one of the target organs attacked by acute and chronic exposure to pesticides [49]. Elevation of creatinine concentrations in serum of treated rats (Table 3 and 4) may be attributed to reduction in glomerular filtration in the kidney and also reflect dysfunction of the kidney tubules. The kidney function impairment could probably occur as a result of oxidative damage [50]. On the other side, decreased levels of urea are indicative of kidney dysfunction. For instance, cypermethrin toxicity was resulted in decreasing metabolism of physiological processes due to degenerative changes in the various segments of nephrons. Subsequently, this was resulted in concomitant enzyme elevation in extracellular fluid [49,50].

In fact, the toxicity of biologically active substances (e.g., pesticides) is associated with the formation of reactive oxygen species (ROS). These ROS are responsible of inducing oxidative stress in the tissues and chronic permanent damage [51]. Such damage occurs in cases of excessive formation of ROS or insufficient of protective antioxidants. Therefore, the harmful effects of ROS are balanced by the antioxidant action of nonenzymatic and enzymatic antioxidants. Antioxidants are molecules that contain an unshared electron [52]. It is well documented that many pesticides may induce oxidative stress following acute exposure in humans [52] and animals [18,19, 53,54]. Increased lipid peroxidation (LPO) in various tissues may be one of the molecular mechanisms involved in the DEL - induced toxicity [55]. LPO is a marker of oxidative damage caused by many substances including pesticides. Malondialdehyde (MDA) is a stable end product of LPO and therefore can be used as an indirect measure of the cumulative LPO. SOD provides the first line of defense against oxygen derived free radicals and decreases oxidative stress by dismutation O2- . Decline of antioxidant enzyme activity by DEL could be attributed to direct effect on SOD either by reduction of the enzyme substrates and/or by down-regulation of transcription and translation processes [56].

Previous studies in our laboratory on rat (Rattus norvegicus), using different insecticides, revealed increase of MDA and decrease of SOD levels following the insecticidal treatments [18-21,53,54], and corroborate our findings on DEL insecticide. Moreover, it was reported that DEL produces oxidative stress represented by significant increase in lipid peroxidation, nitric oxide concentration, and DNA fragmentation percentage, plus significant reduction of total antioxidant capacity (TAC) of DEL-treated groups of rats [56]. Other authors have demonstrated that pyrethroids produce oxidative stress in exposed cells, which leads to reduction in the concentration of thiol groups [57]. Our results revealed that both low and high doses of DEL caused increase of MDA and reduction of SOD and TAC, either in rat dams (Table 3) or in their male and female pups (Table 5).

The hepatic and renal function results corroborated the histopathological lesions observed in the present study (Figure 2 and 3). Generally, the high dose of DEL (1/10 LD50) was more damaging to the tested organs than the low dose (1/100 LD50) and indirect exposure of the offspring during gestation and lactation periods resulted in histological alterations in liver and kidney of the pups. Supporting our findings that DEL was reported to cause some complications such as hypertrophy of liver cells, significant increase in kupfer cells and focal necrosis [58]. Also, in male albino rats treated with DEL (1.28 mg/kg per day) for 30 days showed mild necrotic changes in kidneys. Ultra structural examination showed several changes in renal proximal tubules of DEL-treated group [24]. Our results corroborated with Lamfon [26] who found that albino rats treated with 1/10 LD50 of DEL showed loss of normal structure of the hepatic cells, blood congestion, leucocytic infiltration, cytoplasmic vacuolation of the hepatocytes and fatty degeneration.



Pregnant women are a special risk group based on increased risk of childhood acute lymphocytic leukemia when they use pesticides during pregnancy [59]. The fetus is more vulnerable to the toxic effects of environmental exposures than are children or adults [60]. Highly lipophilic compounds, such as organic pesticides, have the ability to cross the placenta during pregnancy and reach the fetus [61]. Also, there are many factors involved in the transfer of chemicals into the milk and subsequently to the suckling neonate. The factors which can influence transport of the compound during lactation include lipophilicity, ionization, and maternal plasma protein binding [62]. Subsequently, several investigations have been published on DEL toxicity to mammals (e.g., rats and mice) during gestation and effects on offspring.

Since highly lipophilic compounds, such as organic pesticides, may cross the placenta and reach the fetus during pregnancy [61,62], compounds of antioxidative stress can play an important role during pregnancy and lactation periods. To the best of our knowledge, there is no data on amelioration of DEL-induced oxidative stress during pregnancy. However, there are many publications on normal

male and female rats, using leave extract of Ocimum basilicum [22]; ginger extract [23]; Lycopene [24]; Spirulina platensis -a unicellular cyanbacterium [25] ; cinnamon aqueous extract [26]; and propolis at a dose of 100 mg/kg b.w. 3 times/ week for 6 weeks [27]. By other word, information regarding alleviation of DEL- induced toxicity to pregnant rats by an antioxidant such as selenium is lacking and thus investigated here for the first time.

Selenium is an essential trace element of all biological systems. It is present in the active center of glutathione peroxidase (GPx) that protects membrane lipids and macromolecules from oxidative damage produced by peroxides. It is used as nutritional supplements and to improve the activity of the seleno-enzyme [63]. Selenium inhibits membrane LPO by scavenging lipid peroxyl radicals, and converts it into α-tocopheroxyl radical as a consequence [64].

Based on Mansour and Gamet-Pyrastre [18] it was possible to assess the effect of DEL on liver and kidney biomarkers, as well as on antioxidant enzymes (AOEs), in a “quantitative manner” by calculating the percentage of change in DEL-treated groups relative to control

Liver

G1 & G2 G3 G4 (a & b)

G5 G6

Kidney

G1 & G2 G3 G4

G5 G6

Figure 3: Sections of liver and kidney from pups whose mothers were treated with deltamethrin, with and without selenium co-administration. Liver sections of G1 & G2 showing normal histological structure of hepatic lobule from central vein (cv) and normal hepatocytes (h). G3 (1/100 LD50): severe dilatation and congestion were detected in portal vein (pv) while the hepatocytes showed degenerative change (m). G4 (1/10 LD50): severe dilatation and congestion were noticed in the portal vein (pv) associated with inflammatory cells surrounding the bile ducts (bd) in between the hepatocytes. G5 (1/100 LD50 +Se): focal haemorrhage (h) was noticed in the hepatic parenchyma. G6 (1/10 LD50 +Se): few inflammatory cells infiltration was detected in the portal area (pv) and degenerative change in the hepatocytes (m).Kidney sections of G1 & G2 showing showing normal histological structure of the glomeruli (g) and tubules (t) at the cortex. There was focal haemorrhage (h) at the corticomedullary portion in sections of G3 (1/100 LD50) and G4 (1/10 LD50), but was severe in the high dose of DEL. In G5 (1/100 LD50+ Se), there was focal haemorrhage in between the tubuless and mild dilatation and congestion in the portal vein (pv). In G6 (1/10 LD50 + Se), the tubules showed degeneration (d) in the lining epithelium associated with mild congestion in the blood vessels (v) at the cortex (H&E stain 40x).



untreated groups. On the other hand, estimation of the “Amelioration Index; AI” by comparing the results of AOEs (e.g., MDA and SOD) in DEL+ Se groups with the results of control groups, to assess the ameliorative effect of Se. As AI was approaching “1”, the amelioration reaches high degree of normalization to the control value.

Table 7 presents percent of change in the different biochemical parameters in dams and their pups due to exposure to DEL at low (1/100 LD50) and high (1/10 LD50) doses. At the low dose the change in ALT activity accounted to 104.03, 110.46 and 99.96%, respectively in dams, male pups and female pups. Such changes equaled 149.94, 143.63 and 144.95% at the high dose of DEL. By other word, the estimated values reflect how much deviation than normal was occurred due to the tested insecticide. Estimations for AST, ALP, BuChE, urea, creatinine, MDA, SOD and TAC could be depicted from Table 7. It has to note that, changes in BuChE, urea, SOD and TAC were resulted in negative values (i.e. decrease than control). Generally, the high dose of DEL (1/10 LD50) induced more changes than the low dose (1/100 LD50). Changes in dams were higher than those for pups, but gender variation in pups seemed to be affected by the measured biochemical parameters and the tested dose.

The efficiency of Se to alleviate the oxidative stress of DEL is expressed in terms of “Amelioration Index, AI” (Table 8). The AI of Se for MDA equaled 0.95, 1.08 and 1.12, respectively for dams, male pups and female pups at the low dose of DEL. Such indices accounted to 1.24, 1.03 and 1.02, respectively for the high dose of DEL. The AI of Se for SOD was (0.85, 0.92 & 1.01) and (0.70, 0.83 & 0.87) for dams, male and female pups, respectively at the two tested doses of DEL. Similarly, AI for TAC were (0.92, 0.92 & 0.99) and (0.93, 0.93 & 0.81) and AI for BuChE were (0.97, 0.98 &1.01) and (0.80, 1.00 & 0.97). Such results reveal the capacity of Se in ameliorating the oxidative stress induced by DEL. AI of values exceeding 1.0 may refer to either better improvement or negligible experimental errors. The present results are supported by our previously published investigations in the same direction [e.g., 18].

In this respect, it may be of interest to apply the above mentioned assessment on results of an investigation on DEL and alleviation of its oxidative stress by a biological agent. In male albino rats treated with DEL-30 mg /kg bw (1/5 LD50), compared with a group received the DEL dose + Spirulina platenesis (SP) - a unicellular cyanbacterium- at 1000 mg/kg bw (as an antioxidant), Abdel-Daim et al. [25] reported the following results: a) 32.52 nmol/g, 16.91 u/g and 47.39 µmole/g for

Groups Controla Deltamethrin 1/100 LD50

bDeltamethrin 1/10

LD50c

% of changed

1/100 LD50 1/10 LD50

ALT (U/L)Dams

Pups MPups F

24.5724.6625.07

50.1351.950.13

61.4160.0861.41

104.03110.4699.96

149.94143.63144.95

AST (U/L)Dams

Pups MPups F

62.0361.0160.09

70.2372.0171.25

81.0981.280.1

13.2218.0318.57

30.7333.0933.30

ALP (U/L)Dams

Pups MPups F

90.6191.0590.21

240.1244.09250.5

400.5378.9390.5

164.98168.08177.69

342.00316.14332.87

BuChE (U/L)

DamsPups MPups F

3270.13002

2973.3

2550.92105.52230.3

1410.71119.11300.1

-21.99-29.86-24.99

-56.86-62.71-56.27

Urea (mg/dl)Dams

Pups MPups F

42.0340.0942.33

29.0429.931.34

20.0720.1119.09

-30.91-25.42-25.96

-52.25-49.84-54.90

Creatinine (mg/dl)Dams

Pups MPups F

0.680.700.68

1.331.331.51

1.801.811.73

95.5990.00122.06

164.71158.57154.41

MDA (nmol/g tissue)Dams

Pups MPups F

4.13. 94.03

5.64.95.0

6.95.76.03

36.5825.6424.07

68.2946.1549.63

SOD (ug/g tissue)Dams

Pups MPups F

354.90350.01344.33

229.00249.07265.09

111.03120.01133.9

-35.47-28.84-23.01

-68.72-65.71-61.11

TAC (mM/L)Dams

Pups MPups F

1.691.711.88

1.001.231.01

0.80 0.930.87

-40.83-28.07-46.28

-52.66-45.61-53.72

dPercent of change = (b or c − a) / a × 100.

Table 7: Assessment of oxidative stress of deltamethrin based on estimation of percent of change in some biochemical parameters for dams and their pups.



MDA, SOD and TAC, respectively for control group, b) 71.44 nmol/g, 6.69 u/g and 33.59 µmole/g, respectively for DEL-treated group; and c) 46.46 nmol/g, 17.28 u/g and 46.11 µmole/g, respectively for DEL+ SP-treated group. Accordingly, the percent of change in the above three biochemical parameters due to DEL treatments equals 119.7, -60.4 and -29.1%, respectively. On the other hand, the amelioration index (AI) due to co-administration of SP equals 1.4, 1.02 and 0.97, respectively for MDA, SOD and TAC. Such a trial may indicate possibility of assessing the effect of a pesticide on a given biochemical parameters and the amelioration of oxidative stress in a “quantitative manner”.

ConclusionIn light of the results of the present study, it can deduce that

exposure of adult female rats during gestation to deltamethrin (DEL) at 1/10 and 1/100 LD50’s can induce hepatic and renal dysfunction and oxidative stress, as well as histopathological effects in liver, kidney and ovary. Similar toxic effects were observed on the pups (male and female) born from the treated dams. Generally, alterations of the measured biochemical parameters and histopathological changes were occurred in a dose- dependent manner. The capacity of selenium (Se) to minimize or diminish the oxidative stress induced by DEL was expressed in terms of “amelioration index (AI)” which was approaching or equaling 1.0; indicating complete normalization of the concerned parameters, and revealing, for the first time, the important role of Se against deltamethrin-induced oxidative stress in pregnant rats. The findings may support the need to further investigating the adverse effects of exposure to low doses of commonly used pesticides, especially during pregnancy and breast-feeding as well as developmental effects on newborn child.

AcknowledgmentThe authors thank Prof. Dr. Adel Bakir, Pathology Department,

Faculty of Veterinary Medicine, Cairo University, Egypt for reading the histopathological slides.

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