Study offers clues on diet benefits without the diet
By Kate Kelland
LONDON (Reuters) - Experiments which mimicked a low-calorie diet by tinkering with genes in mice extended their lives and prevented disease, and a drug that has the same effect could give people longer, healthier lives, scientists said on Thursday.
British researchers found that deleting a gene linked to nutrients and growth helped mice to live 20 percent longer on average, and partly explained why eating less appears to improve health and increase longevity.
The findings also offered a possible genetic drug target for protecting against aging-related diseases, they said.
"What we have shown is that this gene is one that regulates life span and also determines how healthy animals are in middle and late age," said Dominic Withers of the Center for Diabetes and Endocrinology at University College London.
Withers and his colleagues used so-called knockout mice -- mice bred with a certain gene removed or knocked out -- in this case the ribosomal S6 protein kinase 1 (S6K1) gene.
Deleting S6K1 meant the mice's bodies behaved in a similar way to mammals whose calorie intake is restricted, they said.
"These mice were resistant to type 2 diabetes ... and they also appeared to have reduced incidence of the mouse-equivalent of osteoporosis -- so they had stronger bones," Withers said.
Balance, strength and coordination all improved in the knockout mice, and they were more inquisitive, suggesting their brains were healthier. Continued...