British Journal Of Nutrition · 2009 · 232 citations · 41 references
Ageing has been suggested to cause changes in the intestinal microbial community. In the present study, the microbiota of a previously well-defined group of elderly subjects aged between 70 and 85 years, both non-steroidal anti-inflammatory drugs (NSAID) users (n 9) and non-users (n 9), were further compared with young adults (n 14) with a mean age of 28 years, by two DNA-based techniques: percentage guanine+cytosine (%G+C) profiling and 16S rDNA sequencing. Remarkable changes in microbiota were described with both methods: compared with young adults a significant reduction in overall numbers of microbes in both elderly groups was measured. Moreover, the total number of microbes in elderly NSAID users was higher than in elderly without NSAID. In 16S rDNA sequencing, shifts in all major microbial phyla, such as lower numbers of Firmicutes and an increase in numbers of Bacteroidetes in the elderly were monitored. On the genus level an interesting link between reductions in the proportion of known butyrate producers belonging to Clostridium cluster XIVa, such as Roseburia and Ruminococcus, could be demonstrated in the elderly. Moreover, in the Actinobacteria group, lower numbers of Collinsella spp. were evident in the elderly subjects with NSAID compared both with young adults and the elderly without NSAID, suggesting that the use of NSAID along with age may also influence the composition of intestinal microbiota. Furthermore, relatively high numbers of Lactobacillus appeared only in the elderly subjects without NSAID. In general, the lowered numbers of microbial members in the major phyla, Firmicutes, together with changes in the epithelial layer functions can have a significant effect on the colon health of the elderly.
41
An obesity-associated gut microbiome with increased capacity for energy harvest
Peter J. Turnbaugh, Ruth E. Ley, Michael A. Mahowald et al. · Nature · 2006 · 12.1K citations
Obesity, Nutrition, Energy Harvest +12
Mixed-Effects Models in S and S-PLUS
Technometrics · 2001 · 9.4K citations · Full text
Obesity alters gut microbial ecology
Ruth E. Ley, Fredrik Bäckhed, Peter J. Turnbaugh et al. · Proceedings of the National Academy of Sciences · 2005 · 6.1K citations · Full text
Evolution of Mammals and Their Gut Microbes
Ruth E. Ley, Micah Hamady, Catherine Lozupone et al. · Science · 2008 · 3.7K citations · Full text