Effect of high-altitude hypoxia on function and cytoarchitecture of rats' liver

The liver is central to metabolic, detoxification, and homeostatic functions. Exposure to hypobaric hypoxia at high altitudes causes detrimental effects on the liver, leading to injury. This study evaluated the effect of hypoxia-induced at high altitudes on liver function, oxidative stress, and histopathological changes in rats. This study used 24 male Wistar rats (aged 8-10 weeks). The hypoxia (hypobaric hypoxia) was inducted at a high altitude of 2,100 m above sea level. Normoxia is defined as 40 m above the sea level. The rats were randomly divided into two groups: a control group maintained at low altitudes and an experimental group exposed to high altitudes for eight weeks. Blood samples were collected from all rats through a cardiac puncture, and liver samples were taken through an abdominal approach. All samples were processed through standard methods and evaluated for liver function tests and histopathological assessment. Serum aspartate aminotransferase and alanine transaminase levels significantly increased by 25% and 30%, respectively, in the high-altitude group compared to controls (p < 0.01), indicating mild hepatocellular damage. Oxidative stress assessment indicated a significant elevation in malondialdehyde by 42% in the liver homogenates of high-altitude rats compared to controls (p < 0.001). Moreover, Superoxide dismutase activity and glutathione content decreased by 18% and 22% in the high-altitude group (p < 0.01), confirming the increased oxidative stress. Histologically, minimal inflammatory infiltration was observed in the rat livers at high altitudes, with no signs of necrosis or severe structural changes. Subclinical liver dysfunction, as evidenced by altered serum enzyme levels and increased oxidative stress with mild histological changes, is induced by high-altitude hypoxia in rats. This study's results support that a hypobaric hypoxic environment physiologically stresses the liver. Further research into the long-term implications of hypobaric hypoxia and the adaptive responses of the liver is warranted.