Characterization of the anti-inflammatory Lactobacillus reuteri BM36301 and its probiotic benefits on aged mice.

BACKGROUND: The gut microbiota is playing more important roles in host immune regulation than was initially expected. Since many benefits of microbes are highly strain-specific and their mechanistic details remain largely elusive, further identification of new probiotic bacteria with immunoregulatory potentials is of great interest. RESULTS: We have screened our collection of probiotic lactic acid bacteria (LAB) for their efficacy in modulating host immune response. Some LAB are characterized by suppression of TNF-α induction when LAB culture supernatants are added to THP-1 cells, demonstrating the LAB's anti-inflammatory potential. These suppressive materials were not inactivated by heat or trypsin. On the other hand, treatment of THP-1 directly with live bacterial cells identified a group of pro-inflammatory LAB, which stimulated significant production of TNF-α. Among those, we chose the Lactobacillus reuteri BM36301 as an anti-inflammatory strain and the L. reuteri BM36304 as a pro-inflammatory strain, and further studied their in vivo effects. We supplied C57BL/6 mice with these bacteria in drinking water while feeding them a standard diet for 20 weeks. Interestingly, these L. reuteri strains evoked different consequences depending on the gender of the mice. That is, males treated with anti-inflammatory BM36301 experienced less weight gain and higher testosterone level; females treated with BM36301 maintained lower serum TNF-α as well as healthy skin with active folliculogenesis and hair growth. Furthermore, while males treated with pro-inflammatory BM36304 developed higher serum levels of TNF-α and insulin, in contrast females did not experience such effects from this bacteria strain. CONCLUSION: The L. reuteri BM36301 was selected as an anti-inflammatory strain in vitro. It helped mice maintain healthy conditions as they aged. These findings propose the L. reuteri BM36301 as a potential probiotic strain to improve various aspects of aging issues.

Community involvement, perceived control, and attitudes toward aging among lesbians and gay men.

A person-environment approach was used to explore the relationship between community involvement and attitudes toward aging among middle-age and older lesbians and gay men. Specifically, this study investigated the relationships between participation in gay community activities, perceived control, and aging-related concerns among two partially-overlapping convenience samples of middle-aged and older lesbians and gay men (N = 136). As expected, perceived control was negatively associated with aging concerns, while community involvement was surprisingly positively associated with the latter. Although the hypothesized interaction between control and community participation was not supported, exploratory analysis revealed an interaction between participation and a measure of autonomy in the single men sample. Specifically, the combination of high autonomy and low community participation was associated with the lowest levels of aging-related concern. Findings are discussed with respect to the implications of having aging-related concerns, the limitations of both control and community, and different possible pathways to positive aging.

Single by choice? Assessing and understanding voluntary singlehood among mature gay men.

This study investigated what it means for mature gay men to be voluntary single from the perspective of both assessment and subjective experience. A convenience sample of 94 self-identified single gay men from a large midwestern city, ages 35 and over, completed a structured questionnaire that included the 15-item Adaptation to Single Status Measure. Twenty of these men also participated in semi-structured life-history interviews. Descriptive, item, and scale analyses indicated a discrepancy between the perception of oneself as "single by choice" and acceptance of and satisfaction with single status. Qualitative data indicated that voluntary singlehood is neither a salient identity nor an expression of primary control; rather, it is an idiosyncratic "narrative strategy" and a form of secondary control that preserves ego integrity. These findings are discussed with respect to their implications for the creation and maintenance of healthy, happy, single lifestyles and communities.