Antioxidants might be important in prolonging life, says a new study published in Nature Communications. Along the same lines, drugs and foods containing vitamin B3 might be useful in delaying ageing and the diseases that come with it.
Though ageing has often been associated with the building up of oxidative damage, the relevance of the correlation has been generally downplayed by scientists. The new study, on the other hand, describes it as an important cause of ageing, and that thus antioxidants play an important role in countering its effects.
A group of researchers from the Spanish National Cancer Research Centre (CNIO) working in concert with two teams from the University of Valencia and IMDEA Food from Madrid came to this conclusion after observing the effects of increasing the global antioxidant capacity of cells which they did by genetically enhancing the concentration of NADPH, a key molecule involved in antioxidant reactions. The production of NADPH was boosted by increasing the expression of the enzyme glucose-6-phosphate dehydrogenase (or G6PD). The subjects of the study were transgenic mice.
The results show that increasing NADPH levels increases the organism’s natural antioxidant defences, thereby conferring on it added protection from oxidative damage and the negative effects of ageing like insulin resistance and reduced movement coordination. Another positive effect was an increased longevity.
First author Sandrina Nóbrega-Pereira explains that the cells of the mice became more resistant to treatments with extremely toxic artificial oxidative compounds. These mice also had lower oxidative damage than non-transgenic mice of the same age. Furthermore, the ageing process of the former mice was found to have been delayed: this effect was restricted to females though. Transgenic female mice had a 14% increase in their life span as opposed to non-transgenic ones while transgenic males showed no such effect.
This study is different from other similar studies because the researchers enhanced all antioxidant enzymes; all the natural antioxidant mechanisms of the cells were activated through NADPH. Otherwise, other teams would only administer antioxidants interacting directly with oxygen.
To conclude, the authors mention the potential of nutritional supplements and drugs that boost NADPH levels in delaying both ageing in humans and the associated diseases like diabetes. These foods would include those rich in vitamin B3 which are needed for the production of precursors of NADPH.