erythropoietin, erythropoiesis and chronic mountain ...erythropoietin, erythropoiesis and chronic...
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Erythropoietin, Erythropoiesis and Chronic Mountain Sickness
(CMS)
H.-C. Gunga1, G. Valverde2, H. Spielvogel3, and K. Kirsch1
1Institut für Physiologie, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin 2Universidad Mayor de San Andrés, La Paz, Bolivia
3Instituto Boliviano de Biologia de Altura (IBBA), La Paz, Bolivia
HAPPOM Symposium - LIMA 2007
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! Introduction Evolutionary backgroundOxygen sensing mechanisms
! Methods
! Human studies on EPO, sTfRNormobaric-Normoxic EnvironmentCircadian, monthly, annual variations
Hypobaric-Hypoxic EnvironmentShort, intermittent, and long-term exposure
Chronic Mountain Sickness (CMS)
! Summary and Conclusions
Contents
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Bed restBed rest
Humans in
Extreme Environments
Humans in
Extreme Environments
ComparativePhysiology
ComparativePhysiology
Tropics/Desert
Tropics/Desert
High Altitude
High Altitude
Micro-G(Space)Micro-G(Space)
PalaeophysiologyEvolutionaryAnthropology
PalaeophysiologyEvolutionaryAnthropology
History of Applied Science
History of Applied Science
Nathan Zuntz (1847 – 1920)Operation „Paperclip“
Nathan Zuntz (1847 – 1920)Operation „Paperclip“
ModerateAltitude
(<2,300 m)
ModerateAltitude
(<2,300 m)
HighAltitude
(>3,000 m)
HighAltitude
(>3,000 m)
Real Micro-g
Space (near Earth orbit)Space (near Earth orbit)
Exercise PhysiologyExercise
Physiology
Marathon-running
Marathon-running
SurvivaltrainingSurvivaltraining
HDTHDT IsolationIsolation ImmersionImmersion
GoldMiningGold
Mining
Simulated Micro-g
•Introduction
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5/35Erythropoietin, Erythropoiesis and CMS
Rift Valley, Human Evolution, and Altitude
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Hochachka PW, Gunga HC & Kirsch K.Our ancestral physiological phenotype: An adaptation for
hypoxia tolerance and for endurance performance?PNAS 95: 1915-1920 (1998)
Adaptation and Conservation of Physiological Systems
in Evolution Human Hypoxia Tolerance
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Erythrocytes in different Species
Withers PC. Comparative animal physiology.Saunders 1992
Human red blood cells (7.5 μm; PCV 44% ~ 3.200 m2; Blood volume in mammals 6-8% - diving mammals > 8% of body mass)
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Signal Transduction Pathway - Hypoxia Inducible Factor (HIF-1 alpha)
(Wenger 2002)
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• Erythropoietin (EPO)is a glycoprotein hormone.
• EPO is produced by specialized cells in the kidneys (90 %) and the liver (10 %).
Erythropoietin
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Erythropoietin and Erythropoiesis
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Physiological variables in the
etiology of CMS
CMS/EE:
Severe HypoxemiaPulmonary hypertension
ErythrocytosisConsensus Symptoms....
12/35Erythropoietin, Erythropoiesis and CMS
! Introduction Evolutionary backgroundOxygen sensing mechanisms
! Methods
! Human studies on EPO, sTfRNormobaric-Normoxic EnvironmentCircadian, monthly, annual variations
Hypobaric-Hypoxic EnvironmentShort, intermittent, and long-term exposure
Chronic Mountain Sickness (CMS)
! Summary and Conclusions
Contents
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•EPO (IBL)
Median: 12 mIU/ml Range: 4 -36 mIU/ml
•sTfR (R&D)
Caucasians (living <300 m above sea-level)
Median: 18,4 nmol/l Range 8.7 – 28,1 nmol/l
ELISA Tests
•Methods
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• Transferrin is a transport protein for iron (Fe).
• The diferric (2*Fe) transferrin is binding to TfR.
• During the phase of cellular proliferation iron is incorporatedinto the interior of the erythroblast.
• This is important for the synthesis of hemoglobin.
4-22
Transferrin and Transferrin-receptor
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Transferrin Receptor
• Transferrin Receptor (TfR)is a transmembranal protein, expressed mainly on the surface of erythroid cells
Cell interior
16/35Erythropoietin, Erythropoiesis and CMS
! Introduction Evolutionary backgroundOxygen sensing mechanisms
! Methods
! Human studies on EPO, sTfRNormobaric-Normoxic EnvironmentCircadian, monthly, annual variations
Hypobaric-Hypoxic EnvironmentShort, intermittent, and long-term exposure
Chronic Mountain Sickness (CMS)
! Summary and Conclusions
Contents
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Circadian Variations of Serum Erythropoietin
Gunga HC, Kirsch K, Baartz F, Maillet A, Gharib C, Nalishiti W, Rich I & Röcker L.Erythropoietin under real and simulated microgravity conditions in humans.
Journal of Applied Physiology 81: 761-773 (1996)
•Epo-Studies
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Gunga HC, Kirsch K, Baartz F, Maillet A, Gharib C, Nalishiti W, Rich I & Röcker L.Erythropoietin under real and simulated microgravity conditions in humans.
Journal of Applied Physiology 81: 761-773 (1996)
Erythropoietin during Isolation and Confinement
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Gunga H.C. et al. Erythropoietin regulations in humans under different environmental and experimental conditions. Respiration and Neurobiology. Epub ahead, March 12, 2007
Annual variations of serum erythropoietin concentrations
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Erythropoietin before, during and after moderate
hypobaric-hypoxic exposure (2,315 m)
Gunga HC, Kirsch K, Röcker L & Schobersberger W .Time course of erythropoietin, triiodothyronine, throxine,
and thyroid-stimulating hormone at 2,315 m.Journal of Applied Physiology 76: 1068-1072 (1994)
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Erythropoietin and intermittent
hypobaric�hypoxic exposure(3,600 m)
Gunga HC, Röcker L, Behn C, Hildebrandt W, Koralewski E, Rich I, Schobersberger W & Kirsch K.
Shift working in the Chilean Andes (3,600 m) and its influence on erythropoietin and the low-pressure system.
Journal of Applied Physiology 81: 846-852 (1996)
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The distribution of hematocrit values at sea level, Cerro de Pasco, and Morococha
Winslow and Monge, 1987
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Gender differences in four common high altitude medical
conditions as reported in the literature by
Hultgren (1997)
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N = 105
Females (N = 34)63.5 ± 9.4, min 37.0, max. 80 yrs
Males (N = 71)62.1 ± 11.0, min 35.0, max 89.0 yrs
35-39
40-44
45-49
50-54
55-59
60-64
65-69
70-74
75-79
80-84
85-89
age_group
0
2
4
6
8
10
12
14
16
18
20
22
10
12
8
4
11
23
2
0
2
1
6
8
11
13
10
10 8
0
2
sexfemalemale
Age distribution
Inclusion criteria:
•Whole life at high altitude: (3,600 - 4,100
•Excessive erythrocytosis: [Hct > 60 %]
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Differences between females and males for Hct (p=0.011) and Hb (p=0.011)
female male
55
60
65
70
75
80
Hct
(%)
80
female male
19,0
20,0
21,0
22,0
23,0
24,0
25,0
26,0
Hb
(g/d
l)
80
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No differences between females and males for age, EPO and sTfR
p=0.50
female male
30
40
50
60
70
80
90
year
s
27
p=0.52
female male
0,00
50,00
100,00
150,00
200,00
250,00
[EPO
] (U
/l
2
54
51
67
53
10149
p=0.47
female male
25,00
50,00
75,00
100,00
125,00
150,00
sTf-R
(nm
ol/L
101
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No correlation between the hematological parameters (Hct, Hb) and EPO
55 60 65 70 75 80Hct (%)
0.00
50.00
100.00
150.00
200.00
250.00
[EPO
] (U
/l)
femalesmales
19.0 20.0 21.0 22.0 23.0 24.0 25.0 26.0
Hb (g/dl)
0.00
50.00
100.00
150.00
200.00
250.00
[EPO
] (U
/l)
15-22
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No correlation between the hematological parameters (Hct, Hb) and sTfR
55 60 65 70 75 80Hct (%)
25.00
50.00
75.00
100.00
125.00
150.00
sTf-R
(nm
ol/l
19.0 20.0 21.0 22.0 23.0 24.0 25.0 26.0Hb (g/dl)
25.00
50.00
75.00
100.00
125.00
150.00
sTf-R
(nm
ol/l)
femalesmales
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No correlation between age, EPO, and sTfR
years30 40 50 60 70 80 90
0.00
50.00
100.00
150.00
200.00
250.00
[EPO
] (U
/l)
femalesmales
30 40 50 60 70 80 90years
25.00
50.00
75.00
100.00
125.00
150.00
sTf-R
(nm
ol/l)
17-22
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No correlation between EPO and sTfR in the majority of the subjects with high sTfR
25.00 50.00 75.00 100.00 125.00 150.00sTf-R (nmol/l)
0.00
50.00
100.00
150.00
200.00
250.00
[EPO
] (U
/l)
femalesmales
28nmol/l
36 U/l
31/35Erythropoietin, Erythropoiesis and CMS
! Introduction Evolutionary backgroundOxygen sensing mechanisms
! Methods
! Human studies on EPO, sTfRNormobaric-Normoxic EnvironmentCircadian, monthly, annual variations
Hypobaric-Hypoxic EnvironmentShort, intermittent, and long-term exposure
Chronic Mountain Sickness (CMS)
! Summary and Conclusions
Contents
32/35Erythropoietin, Erythropoiesis and CMS
• Males are more frequently affected by EE than females
• Males with EE show higher Hct and [Hb]
• High [sTfR] in the majority of the subjects with EE but no correlation to [EPO]
• Effects of blood letting on circulating [EPO] have to be clarified in patients with EE
• Effects of iron status/metabolism on hematopoiesis in patients with EE are unclear
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Physiological variables in the
etiology of CMS
34/35Erythropoietin, Erythropoiesis and CMS
Winslow, Statham and Gibson, 1979
Changes induced by decreasing the hematocrit in eight patients with CMS
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Arterial oxygen saturation (SaO2) in long-term high altitude residents while awake (A) and during stages of sleep (1-REM) at 3,100 m
During sleep hypoxemia occurs in polycythemics but not in normals. Ear oximeter data.
Kryger and Grover, 1983
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Arterial PCO2 in normal high altitude residents (N=159) and patients with CMS (N=22)Differences in the height of the curves represent different numbers of subjects and patients studied
Cruz and Recavarren, 1982
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Richalet et al, 2005
Mean nocturnal O2 saturation (A) and apnea-hypopnea index (B) in groups of patients before and after treatment with 250 (D250) or 500 (D500) mg of Acetazolamide
compared with a CMS placebo-treated group (Placebo) and normal control subjects (Nb = number of events)
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Erythropoietin during long-term simulated micro-g conditions (Head-down tilt �6°)
Gunga HC, Kirsch K, Baartz F, Maillet A, Gharib C, Nalishiti W, Rich I & Röcker L.Erythropoietin under real and simulated microgravity conditions in humans.
Journal of Applied Physiology 81: 761-773 (1996)
39/35Erythropoietin, Erythropoiesis and CMS
40/35Erythropoietin, Erythropoiesis and CMS
Modulation of Erythropoietin Regulation in Dogs
Ehmke J, Just A, Eckhardt KU, Persson PB, Bauer C & Kirchheim HR.Modulation of erythropoietin formation by changes in blood volume in conscious dogs.
Journal of Physiology 488: 181-191 2 (1996)
•Conclusions
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Vásquez R., and Villena M. (2001). Normal Hematological Valuesfor Healthy Persons Living at 400 Meters in Bolivia. High AltitudeMedicine & Biology 3:361-367
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The morphology of red blood cells at high altitudes
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Red-cell indexes in subjects at low and high altitudes
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Two main Groups: �normal� [EPO] (< 36 U·l-1) and with very high [EPO] (> 100 U·l-1). What about the �intermediates� (36≤[EPO]≤100)
Hct (%)
Cut-off EPO � HA ?
55 60 65 70 75 80
0.00
50.00
100.00
150.00
200.00
250.00[E
PO] (
U/l)
femalesmales
36 Ul
100.0 Ul
????
B
A
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At least two groups with excessive erythrocytosis (EE):
• “normal” [EPO] (< 36 U·l-1)• very high [EPO] (> 100 U·l- 1)
No studies before evaluated “normal” reference levels for [EPO] and [sTfR]in altitude residents
" can the published cut-off values be adopted ?
18-22
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Effect of high altitude (4,300 m) on hematocrit levels of men and woman
Hannon et al. 1966
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Normal hematocrit values at sea level as a function of age for 7,426 normal males and 7,704 normal females in the United States
(Fulwood 1982)
50/35Erythropoietin, Erythropoiesis and CMS
Vásquez R., and Villena M.Normal Hematological Values for Healthy Persons Living at 400 Meters in Bolivia.
High Altitude Medicine & Biology 3:361-367 (2001)
Histograms of showing frequency (counts) for
hematocrit values and the mean and 2 standard deviation (SD) values
observed in 1934, 15- to 29 healthy male and female residents in
Potosi, Bolivia (4,000 m)