Telomeres are elongated in rats exposed to moderate altitude

Journal of Physiological Anthropology

Ri-Li Ge²  Zhenzhong Bai¹  Yanxia Zhao¹  Lan Ma¹  Yingzhong Yang¹  Wen-di Zhou³  Yaping Wang¹ 

[1] Research Center for High Altitude Medical Sciences, University School of Medicine, 810001 Xining, Qinghai, China;Internal Medicine, Research Center for High Altitude Medical Sciences, Qinghai University School of Medicine, 16 Kunlun Rd, 810001 Xining, Qinghai, China;Department of Pediatrics, Huai'an First People’s Hospital, Nanjing Medical University, 6 Beijing Road West, 223300 Huai'an, China

关键词: Malondialdehyde;    Superoxide dismutase;    Hypoxia-inducible factor 1α;    Altitudes;    Telomere;   

Others  :  861286
DOI  :  10.1186/1880-6805-33-19

 received in 2014-05-07, accepted in 2014-06-20,  发布年份 2014

【 摘 要 】

Background

Leukocyte telomere length has been shown to be associated with life span. Hypoxia-associated changes of telomere length have been detected in cell cultures, but no in vivo studies have reported the changes of telomere length under different hypoxic conditions. This study aimed to evaluate the effects of altitude on telomere length in rat leukocytes.

Methods

One hundred and ten male Wistar rats were randomized into 3 groups and maintained at sea-level (altitude of 10 m) (SL group, n = 10), moderate altitude (2,260 m) (MA group, n = 50), or simulated high altitude (5,000 m (SHA group, n = 50). The last two groups were further divided into 5 subgroups and exposed to hypoxia for 1, 3, 7, 15, or 30 days (n = 10). The leukocyte telomere length, hemoglobin concentration, red blood cell count, hematocrit, and plasma levels of telomerase reverse transcriptase (TERT), hypoxia-inducible factor 1α (HIF-1α), malondialdehyde (MDA) and superoxide dismutase (SOD) were measured.

Results

Leukocyte telomere length was significantly longer in the MA group than in the SL or SHA groups, and the TERT expression changed in a similar manner as the leukocyte telomere length. However, HIF-1α level was significantly higher in both MA and SHA groups than the SL group. SOD level was decreased and MDA level was elevated in SHA group.

Conclusions

The telomere length of blood leukocytes is elongated at a moderate altitude, but not at a high altitude. A mild hypoxic state may increase telomere length.

【 授权许可】

   
2014 Wang et al.; licensee BioMed Central Ltd.

【 图 表 】

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