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Acute and chronic exposition of mice to severe hypoxia: the role of acclimatization against skeletal muscle oxidative stress
- Source :
- Repositório Científico de Acesso Aberto de Portugal, Repositório Científico de Acesso Aberto de Portugal (RCAAP), instacron:RCAAP
- Publication Year :
- 2005
-
Abstract
- The role of acclimatization and the effect of persistent severe hypoxia (7000 m) were analyzed in mice soleus muscle with respect to oxidative stress (glutathione redox status) and damage markers (TBARS and SH protein groups), NAG and SOD activities and HSP70 expression. Forty mice were divided into one normobaric-normoxic control group and four hypobaric-hypoxic experimental groups (n = 8). One experimental group (1 D) was acutely exposed to a simulated altitude of 7000 m in a hypobaric chamber for 1 day. Another experimental group (ACCL + 1 D) was exposed to a 3 days acclimatization period plus 1 day of hypoxia exposure at 7000 m. The third experimental group (ACCL + 8 D) was exposed to the same acclimatization protocol, remaining 8 subsequent days at 7000 m. The fourth experimental group (8 D) was chronically exposed without acclimatization. ACCL + 1 D showed a significant decrease (p < 0.05) in oxidative stress and damage compared to the 1 D group. Concerning chronic severe hypoxia, acclimatization was truly vital, since 8 D animals died after 5 days of exposure. Oxidative stress and damage markers in ACCL + 8 D tended to gradually increase throughout the 8 days of the hypoxic period. Total SOD activity did not change in 1 D compared to control; however, it increased significantly (p < 0.05) in ACCL + 1 D and ACCL + 8 D. HSP70 expression followed the observed oxidative stress and damage pattern, suggesting a protective role against hypoxia-induced oxidative stress. The present study supports the hypothesis that acclimatization attenuates oxidative stress and damage induced by acute hypoxia, although a trend to a gradually increased oxidative deleterious effect in skeletal muscle seems to occur during persistent severe hypoxia even after a previous acclimatization period.
- Subjects :
- medicine.medical_specialty
Physical Therapy, Sports Therapy and Rehabilitation
Biology
Health sciences [Medical and Health sciences]
medicine.disease_cause
Acclimatization
Ciências da saúde [Ciências médicas e da saúde]
chemistry.chemical_compound
Mice
Internal medicine
medicine
TBARS
Animals
Orthopedics and Sports Medicine
HSP70 Heat-Shock Proteins
Hypoxia
Muscle, Skeletal
Soleus muscle
Altitude
Skeletal muscle
Health sciences
Glutathione
Hypoxia (medical)
Adaptation, Physiological
Surgery
Disease Models, Animal
Oxidative Stress
medicine.anatomical_structure
Endocrinology
chemistry
Hypobaric chamber
medicine.symptom
Oxidative stress
Ciências da saúde
Subjects
Details
- ISSN :
- 01724622
- Volume :
- 26
- Issue :
- 2
- Database :
- OpenAIRE
- Journal :
- International journal of sports medicine
- Accession number :
- edsair.doi.dedup.....04e411f4b0fa2f0e2929ffd0f7d21ef4