PLASMA AND CEREBROSPINAL FLUID BETA-ENDORPHIN LEVELS SHOW A STRONG CORRELATION IN CHILDREN

WITH CEREBRAL MALARIA. 1 1 1 2Oluwagbemiga O ADEODU Oluwatosin E OLORUNMOTENI Saheed BA OSENI Efere M OBUOTOR

1Department of Paediatrics, Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife. 2Department of Biochemistry, Obafemi Awolowo University, Ile-Ife.

BACKGROUND

Beta-endorphin (β-endorphin) is an endogenous opioid peptide that is synthesized in the brain. It is found mainly in the plasma and cerebrospinal fluid (CSF). Known to play a role in analgesia and in neuroendocrine regulation. It is also known that endorphin levels rise during stress and inflammation suggesting that β-endorphin may also have a role to play in encephalopathy such as cerebral malaria. There is no previous study on the relationship between β-endorphin levels in the CSF and plasma of children with cerebral malaria (CM). Thus the objective of this study was to determine the relationship between β-endorphin levels in the CSF and plasma of children with cerebral malaria.

METHODS

A Cross-sectional study of 40 children with CM aged between eight and 84 months was conducted at Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife. One milliliter of blood was collected from each subject for the determination β-endorphin levels. CSF and plasma β-endorphin levels were determined using ELISA kit at the Department of Biochemistry, Obafemi Awolowo University (OAU) Ile-Ife. Data was analysed using the Statistical Programme for Social Sciences (SPSS) software for Windows version 16.0. The level of statistical significance for the various tests of associations was set at probability value (p-value) of less than 0.05.

RESULTS

The mean (± SD) CSF β-endorphin level is 1.8 ± 0.9 pmol/ L. The mean (± SD) plasma β-endorphin level is 3.1 ± 2.0 pmol/ L . The plasma β-endorphin levels significantly correlated positively with CSF β-endorphin ® = 0.568, p = 0.001). For every unit rise in plasma β-endorphin, CSF β-endorphin rises by 0.252 pmol/ L (Confidence interval 0.132 to 0.371 pmol/ L).

VARIABLE SUBJECTSN (% )

AGE DISTRIBUTION

6-12 months

13-24 months

25-36 months

37-60 months

>60 months

4 (10.0)

16 (40.0)

10 (25.0)

6 (15.0)

4 (10.0)

GENDER DISTRIBUTION

Male 25 (62.5)

Female 15 (37.5)

Key : n=number(frequency)

Table I: Demographic Characteristics

Figure 1: Correlation between plasma and CSF levels .β-endorphin

Plasma B-Endorphin at admission

y = 0.2517x+ 1.0194r = 0.5682

R = 0.3229p = 0.000

CS

F B

-En

do

rph

in

4

3.5

3

2.5

2

1.5

1

0.5

0

0 2 4 6 8 10 12

DISCUSSIONThe plasma β-endorphin levels seen in children with CM in this study were higher than CSF levels. Though little transport of β-endorphin between CSF and plasma may occur through circumventricular organs and P-glycoprotein. However, there is BBB disruption in inflammation or infection. It may be contributory to higher plasma β-endorphin levels. The positive correlation between plasma and CSF β-endorphin levels in this study may suggest a possible communication between the plasma and CSF in cerebral malaria due to distruption of BBB.

CONCLUSIONS

Thus, plasma levels of β-endorphin may be a reflection of the levels in CSF. Since there is a significant positive correlation between plasma and CSF β-endorphin levels, it may suffice to analyse plasma β-endorphin levels only in studies on children with CM where repeated lumbar puncture may be unethical.

REFERENCES1. Nagamitsu S. CSF beta-endorphin levels in pediatric neurologic disorders. Kurume Med J 1993; 40:233-41.2. Veening JG, Gerrits PO, Barendregt HP. Volume transmission of beta- endorphin via the cerebrospinal fluid; a review. Fluids and Barriers of the CNS 2012; 9:16. 3. Ogala WN. Infectious diseases: Malaria. In: Azubuike JC, Nkanginieme KEO, editors. Paediatrics and child health in a tropical region. 2nd ed. Owerri: African Educational Services; 2007. 596-604.Dr. Oluwatosin Eunice Olorunmoteni

Department of Paediatrics, Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Osun State, Nigeria. E mail: doc_tosino@yahoo.com or tosinolorunmoteni@gmail.com Phone number: +234803 941 3535

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