| Title: | "Association of Age with the Expression of Hypoxia-Inducible Factors HIF-1alpha, HIF-2alpha, HIF-3alpha and VEGF in Lung and Heart of Tibetan Sheep" |
| Author(s): | He Y; Munday JS; Perrott M; Wang G; Liu X; |
| Address: | "College of Animal Science and Technology/Gansu Provincial Key Laboratory of Ariland Crop Science, Gansu Agricultural University, Lanzhou 730070, China. heyanyuxy@sina.com. School of Veterinary Science, Massey University, Palmerston North 4410, New Zealand. J.munday@massey.ac.nz. School of Veterinary Science, Massey University, Palmerston North 4410, New Zealand. m.r.perrott@massey.ac.nz. College of Animal Science and Technology/Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China. 13680740a@sina.com. College of Animal Science and Technology/Gansu Key Laboratory of Herbivorous Animal Biotechnology, Gansu Agricultural University, Lanzhou 730070, China. liuxiu@gsau.edu.cn" |
| ISSN/ISBN: | 2076-2615 (Print) 2076-2615 (Electronic) 2076-2615 (Linking) |
| Abstract: | "Hypoxia-inducible factors (HIFs) play an important role in mediating the physiological response to low oxygen environments. However, whether the expression of HIFs changes with age is unknown. In the present study, the effect of aging on HIF-1alpha, HIF-2alpha, HIF-3alpha and VEGF expression in the heart and lung of 30 Tibetan sheep that were adapted to hypoxia was evaluated. The 30 sheep were subdivided into groups of 10 animals that were 1, 2 or 6 years of age. Immunohistochemistry for HIF-1alpha, HIF-2alpha, HIF-3alpha and VEGF revealed that the immunostaining intensity of VEGF protein in the heart and lung was significantly higher than the intensity of immunostaining against the HIFs (p < 0.05). HIF-1alpha and HIF-2alpha protein translocated into the nucleus of cardiac muscle cells. However, immunostaining for HIF-3alpha was restricted to the cytoplasm of the myocardial cells. Immunostaining for HIF-1alpha, HIF-2alpha, HIF-3alpha and VEGF was detected within alveolar macrophages. The concentration of HIF-1alpha and HIF-2alpha was higher in the lung of 1-year-old than 6-year-old sheep (p < 0.05). In contrast, HIF-3alpha and VEGF immunostaining was most prominent in the hearts of the oldest sheep. However, when RT-PCR was used to evaluate RNA within the tissues, the expression of all four studied genes was higher in the lung than in the heart in the 1-year-old sheep (p < 0.05). Furthermore, VEGF and HIF-3alpha gene expression was higher in the heart from 1-year old than 6-year old sheep (p < 0.05). However, in the lung, HIF-1alpha and HIF-2alpha gene expression was lower in 1-year old than 6-year old sheep (p < 0.05). We conclude that HIF-3alpha and VEGF may play be important in how the heart responds to hypoxia. Additionally, HIF-1alpha and HIF-2alpha may have a role in the adaptation of the lung to hypoxia. The expression of these proteins in alveolar macrophages suggests a potential role of these cells in the physiological response to hypoxia. These results are useful in understanding how age influences the hypoxia adaption mechanisms of the heart and lung and may help to better understand chronic mountain sickness that is commonly observed in Tibetan people living on the Qinghai-Tibetan plateau" |
| Keywords: | HIFs Tibetan sheep Vegf heart and lung hypoxia macrophage; |
| Notes: | "PubMed-not-MEDLINEHe, Yanyu Munday, John S Perrott, Matthew Wang, Guan Liu, Xiu eng Switzerland 2019/09/14 Animals (Basel). 2019 Sep 11; 9(9):673. doi: 10.3390/ani9090673" |
