Alcohol induced alterations to the human fecal VOC metabolome

Studies have shown that excessive alcohol consumption impacts the intestinal microbiota composition, causing disruption of homeostasis (dysbiosis). However, this observed change is not indicative of the dysbiotic intestinal microbiota function that could result in the production of injurious and toxic products. Thus, knowledge of the effects of alcohol on the intestinal microbiota function and their metabolites is warranted, in order to better understand the role of the intestinal microbiota in alcohol associated organ failure. Here, we report the results of a differential metabolomic analysis comparing volatile organic compounds (VOC) detected in the stool of alcoholics and non-alcoholic healthy controls. We performed the analysis with fecal samples collected after passage as well as with samples collected directly from the sigmoid lumen. Regardless of the approach to fecal collection, we found a stool VOC metabolomic signature in alcoholics that is different from healthy controls. The most notable metabolite alterations in the alcoholic samples include: (1) an elevation in the oxidative stress biomarker tetradecane; (2) a decrease in five fatty alcohols with anti-oxidant property; (3) a decrease in the short chain fatty acids propionate and isobutyrate, important in maintaining intestinal epithelial cell health and barrier integrity; (4) a decrease in alcohol consumption natural suppressant caryophyllene; (5) a decrease in natural product and hepatic steatosis attenuator camphene; and (6) decreased dimethyl disulfide and dimethyl trisulfide, microbial products of decomposition. Our results showed that intestinal microbiota function is altered in alcoholics which might promote alcohol associated pathologies.

The approach to sample acquisition and its impact on the derived human fecal microbiome and VOC metabolome

Recent studies have illustrated the importance of the microbiota in maintaining a healthy state, as well as promoting disease states. The intestinal microbiota exerts its effects primarily through its metabolites, and metabolomics investigations have begun to evaluate the diagnostic and health implications of volatile organic compounds (VOCs) isolated from human feces, enabled by specialized sampling methods such as headspace solid-phase microextraction (hSPME). The approach to stool sample collection is an important consideration that could potentially introduce bias and affect the outcome of a fecal metagenomic and metabolomic investigation. To address this concern, a comparison of endoscopically collected (in vivo) and home collected (ex vivo) fecal samples was performed, revealing slight variability in the derived microbiomes. In contrast, the VOC metabolomes differ widely between the home collected and endoscopy collected samples. Additionally, as the VOC extraction profile is hyperbolic, with short extraction durations more vulnerable to variation than extractions continued to equilibrium, a second goal of our investigation was to ascertain if hSPME-based fecal metabolomics studies might be biased by the extraction duration employed. As anticipated, prolonged extraction (18 hours) results in the identification of considerably more metabolites than short (20 minute) extractions. A comparison of the metabolomes reveals several analytes deemed unique to a cohort with the 20 minute extraction, but found common to both cohorts when the VOC extraction was performed for 18 hours. Moreover, numerous analytes perceived to have significant fold change with a 20 minute extraction were found insignificant in fold change with the prolonged extraction, underscoring the potential for bias associated with a 20 minute hSPME.

Evaluating a Peer Intervention Strategy for the Promotion of Sexual Health-Related Knowledge and Skills in 10- to 14-Year-Old Girls. Findings from the “Entre Amigas” Project in Nicaragua

Purpose.

Report effects on knowledge of sexual health and gender from an intervention using peer methodology in Nicaragua.

Design.

A prepost nonequivalent control group design.

Setting.

Ciudad Sandino, Managua, Nicaragua.

Subjects.

A total of 599 girls were surveyed, 60% nonintervened and 40% intervened.

Intervention.

Peer methodology consisted of (1) meetings in which girls talked and worked with other girls, (2) mothers taking an active role in the peer groups, and/or (3) girls watching the soap opera “Sexto Sentido.”

Measures.

Indices measuring changes in sexual knowledge and gender vision.

Results.

Girls participating in the peer groups were twice as likely to have satisfactory sexual health-related self-esteem as those who did not participate. Eleven percent of the girls achieved satisfactory self-esteem as a result of the (peer groups × mothers) interaction and 15% due to the (peer groups × mothers × “Sexto Sentido”) interaction. Girls participating in the peer groups were three times as likely to have satisfactory gender visions; if exposed to all three components, they were almost four times as likely to develop satisfactory gender visions.

Conclusions.

Peer methodology, participation of a female family member, and an educational soap opera seem beneficial in promoting sexual health-related knowledge and gender vision in young girls.