Continuous hypoxia can extend lifespan

(MainsGS3:Science and Technology- developments and their applications and effects in everyday life.)

Context:

• According to a recent study published in PLOS Biology, the lower oxygen content at high altitudes increases lifespan significantly in aging mice.
• The researchers have noted that theirs is the first study to demonstrate that oxygen restriction, or continuous hypoxia, can extend lifespan in an ageing mammal.

Effect of hypoxia:

• The researchers tried to understand how hypoxia affects the body, leading to longer lifespan.
• They examined whether hypoxia prompted the mice to restrict their diets but they found that the hypoxic mice ate slightly more food than those living in normoxia, ruling out dietary restriction as the fundamental underlying mechanism.
• The animals housed in hypoxic conditions also displayed better neurologic function than their counterparts living in normoxic conditions.

Significance of study:

• The study provides valuable insights into the potential of hypoxia to enhance healthy lifespan. 
• The findings open up new avenues for exploring the mechanisms underlying hypoxia’s impact on lifespan and hold promise for potential interventions in the future.
• However, ageing is a highly complex phenomenon which involves numerous molecular mediators thus hypoxia may not target many aspects of ageing since it doesn’t affect the expression of a gene (p21) that’s an important marker of ageing.

Address limitations:

• Caution should be exercised in directly translating these findings to human populations.
• As more work is required to establish their applicability and to address limitations, including variations in species, environmental conditions, and broader health outcomes.
• Further there is no direct evidence that people living at high altitude have a longer maximal lifespan.
• But there are some clues that median lifespan might be increased at higher altitude, and the most interesting epidemiological clue about the human health effects of living at altitude is actually provided by modern Indian history.

Case study: 

• A study published in 1977 shows the comparative health outcomes of 1.3 lakh soldiers stationed on plains and their 20,000 comrades stationed at 3,700-5,600 metres above sea level, over three years. 
• It found that the incidence of common age-related disorders like diabetes, hypertension, and heart disease was lower among soldiers at the high altitudes than those at sea level.

Conclusion:

• A lot more work is required to understand the effect of hypoxia on ageing in people and the molecular mechanisms through which it might be beneficial.