IMPACT OF HYPOBARIC HYPOXIA ON THE PATHOPHYSIOLOGY OF GI SYSTEM : EVALUATION OF THE ROLES OF INDIGENOUS MICROBIOTA

Abstract

High altitude expedition is characterized by a cluster of acute or chronic physiological complications including gastrointestinal hazards, and often called as high altitude sickness (HAS). This environment has an extraordinary stress by the assemblage of reduced air volume with low oxygen concentration, reflected solar light with radiation and increased air current with low temperature. The exclusive criterion, hypobaric hypoxia causes a mild to serious peril to nearly all lives. In spite, the interests of mountain tourism and the practice of sports are gaining massive importance at high altitude area recently. A range of symptomatic and asymptomatic gastrointestinal (GI) disorders are very common in such expeditions. The emerging and surprising consideration of recent time is that gut is our ‘second brain’ as its functions are reportedly entangled with the virtual brain. The cross talk between the flora and host are mediated via enteric nervous system and ultimately controlleds the physiological wellness of the host. This review mainly highlights about the impact of high altitude expeditions on the microbial structure of gut as well as the gut health. Therefore, the goal of the present report are: (1) to summarize the main adaptations of the body at high altitude, introducing the concepts of altitude sickness and oxygen free radicals and their relation; (2) to propose a mechanism of action in the development of the pathology due to alteration of indigenous gut microbiota at this environmental stressed condition.