Unwanted effect of Antibiotic (ab)use - Effect on mitochrondrial gene expression!

Contributed by: Dr. Akilesh Ramasamy & Dr. Tamhankar

Antibiotic use has a profound influence on the gut flora. It's a well known effect. But a recent study reveals the effects could be more devastating and far reaching than previously known.

"Just in the past decade a whole new universe has opened up about the far-reaching effects of antibiotic use, and now we're exploring it. The study of microbiota is just exploding. Nothing we find would surprise me at this point." Prof. Morgan

Prof. Audrey Morgan and his colleagues have found that antibiotics have effect on many other things apart from the endogenous microflora. They seem to affect glucose metabolism, the immune system, food digestion and behaviour. They also suspect it is linked to obesity and stress. The researchers used the mouse model of microbiota depletion by a cocktail of antibiotics in this study.

Some of the alarming results they found apart from the direct effect of antibiotics on the gut microflora were:

1. Antibiotics kill intestinal epithelium cells directly.
2. Antibiotics inhibited mitochondrial gene expression.

Antibiotics may impair effectiveness of Flu vaccines - A study in ice revels.

Contributed by: Dr. Akilesh R & Dr. Tamhankar

A new study suggests antibiotics may hinder the effectiveness of flu vaccines!

Via Creative Common

“Our results suggest that the gut microbiome may be exerting a powerful effect on immunity to vaccination in humans, even immunity induced by a vaccine that is given at a distant site,” says Pulendran, Charles Howard Candler professor of pathology and laboratory medicine at Emory University School of Medicine and Yerkes National Primate Research Center.

In an earlier study involving humans, it was found that expression of the gene encoding TLR5 was correlated to increased antibody response weeks later. TLR5 encodes a protein that enables immune cells to sense flagellin, the main structural protein for the whips (flagella) many bacteria use to propel themselves.

Antibiotics may remove most of the gut bacteria which in turn may affect expression of genes encoding TLR5. In the current study on mice, they found that mice lacking TLR5 had diminished response to flu vaccine.