Gut Bifidobacteria Populations in Human Health and Aging

Abstract

The intestinal microbiota has increasingly been shown to have a vital role in various aspects of human health. Indeed, several studies have linked alterations in the gut microbiota with the development of different diseases. Among the vast gut bacterial community, Bifidobacterium is a genus which dominates the intestine of healthy breast-fed infants whereas in adulthood the levels are lower but relatively stable. The presence of different species of bifidobacteria changes with age, from childhood to old age. Bifidobacterium longum, B. breve, and B. bifidum are generally dominant in infants, whereas B. catenulatum, B. adolescentis and, as well as B. longum are more prevalent in adults. Increasingly, evidence is accumulating which shows beneficial effects of supplementation with bifidobacteria for the improvement of human health conditions ranging from protection against infection to different extra- and intra-intestinal positive effects. Moreover, bifidobacteria have been associated with the production of a number of potentially health promoting metabolites including short chain fatty acids, conjugated linoleic acid and bacteriocins. The aim of this mini-review is to describe the bifidobacteria compositional changes associated with different stages in life, highlighting their beneficial role, as well as their presence or absence in many disease states.

Inflammaging and the Lung

“…Some believe that taking the indirect approach of reducing intestinal inflammation or restoring the intestinal microbiota may have benefit, but this is not without controversy. 120–122 It would be of interest to determine if patients receiving anti-inflammatory therapies for other conditions have restored intestinal barrier function and if this, in turn, improves systemic responses to the injury or infection in the aged population. Further exploration of these direct and indirect avenues of therapeutic manipulation may be of benefit to the overall health of the aged and with that will likely improve overall lung health of the elderly.…”

Bifidobacterium Bacteremia: Clinical Characteristics and a Genomic Approach To Assess Pathogenicity

“…longum are the major bifidobacterial species in the adult intestinal flora, and Bifidobacterium longum subsp. infantis and Bifidobacterium breve are the predominant species in the intestinal tract of human infants (3)(4)(5). Selected members of the genus Bifidobacterium are believed to exert health benefits to the host, including competitive exclusion of pathogens (6,7), modulation of the immune system (8,9), and degradation of diet-derived carbohydrates (10).…”

Exploring the role of the microbiota member Bifidobacterium in modulating immune-linked diseases

“…In humans, Bifidobacterium resides within the GI tract, from birth to old age, which has recently been reviewed by Arboleya et al [17]. Briefly, bifidobacteria colonise the new-born gut within the first days and weeks after birth, and they represent the most abundant bacterial family ranging from 40 to 80% of the total gut microbiota [18,19].…”

“…As the infant begins to consume solid foods (∼6 months onwards), overall bacterial diversity increases in response to an expanding nutritional environment, and the abundance of bifidobacteria decreases quite rapidly to 30-40% [17,31], and continues to fall gradually during childhood and adolescence. This can be an unstable time period, and Bifidobacterium levels can be influenced by puberty, nutrition, and antibiotic use [32][33][34].…”