Andre Mu

Maintenance of energy balance is essential for overall organismal health. Mammals have evolved complex regulatory mechanisms that control energy intake and expenditure. Traditionally, studies have focused on understanding the role of macronutrient physiology in energy balance. In the present study, we examined the role of the essential micronutrient iron in regulating energy balance. We found that a short course of dietary iron caused a negative energy balance resulting in a severe whole body wasting phenotype. This disruption in energy balance was because of impaired intestinal nutrient absorption. In response to dietary iron-induced negative energy balance, adipose triglyceride lipase (ATGL) was necessary for wasting of subcutaneous white adipose tissue and lipid mobilization. Fat-specific ATGL deficiency protected mice from fat wasting, but caused a severe cachectic response in mice when fed iron. Our work reveals a mechanism for micronutrient control of lipolysis that is necessary for regulating mammalian energy balance.

Mouthwash is a commonly used product and has been proposed as an alternative intervention to prevent gonorrhea transmission. However, the long-term effects of mouthwash on the oral microbiota are largely unknown. We investigated the impact of 12 weeks of daily mouthwash use on the oropharyngeal microbiota in a subset of men who have sex with men who participated in a randomized trial comparing the efficacy of two alcohol-free mouthwashes for the prevention of gonorrhea. We characterized the oropharyngeal microbiota using 16S rRNA gene sequencing of tonsillar fossae samples collected before and after 12 weeks of daily use of Listerine mouthwash or Biotène dry mouth oral rinse. Permutational multivariate analysis of variance (PERMANOVA) was used to assess differences in oropharyngeal microbiota composition following mouthwash use. Differential abundance testing was performed using ALDEx2, with false-discovery rate correction. A total of 306 samples from 153 men were analyzed (Listerine, n = 78 and Biotène, n = 75). There was no difference in the overall structure of the oropharyngeal microbiota following Listerine or Biotène use (PERMANOVA P = 0.413 and P = 0.331, respectively). Although no bacterial taxa were significantly differentially abundant following Listerine use, we observed a small but significant decrease in the abundance of both Streptococcus and Leptotrichia following Biotène use. Overall, our findings suggest that daily use of antiseptic mouthwash has minimal long-term effects on the composition of the oropharyngeal microbiota. IMPORTANCE Given the role of the oral microbiota in human health, it is important to understand if and how external factors influence its composition. Mouthwash use is common in some populations, and the use of antiseptic mouthwash has been proposed as an alternative intervention to prevent gonorrhea transmission. However, the long-term effect of mouthwash use on the oral microbiota composition is largely unknown. We found that daily use of two different commercially available mouthwashes had limited long-term effects on the composition of the oropharyngeal microbiota over a 12-week period. The results from our study and prior studies highlight that different mouthwashes may differentially affect the oral microbiome composition and that further studies are needed to determine if mouthwash use induces short-term changes to the oral microbiota that may have detrimental effects.

The upcoming Convention on Biological Diversity (CBD) meeting, and adoption of the new Global Biodiversity Framework, represent an opportunity to transform humanity’s relationship with nature. Restoring nature while meeting human needs requires a bold vision, including mainstreaming biodiversity conservation in society. We present a framework that could support this: the Mitigation and Conservation Hierarchy. This places the Mitigation Hierarchy for mitigating and compensating the biodiversity impacts of developments (1, avoid; 2, minimize; 3, restore; and 4, offset, toward a target such as “no net loss” of biodiversity) within a broader framing encompassing all conservation actions. We illustrate its application by national governments, sub-national levels (specifically the city of London, a fishery, and Indigenous groups), companies, and individuals. The Mitigation and Conservation Hierarchy supports the choice of actions to conserve and restore nature, and evaluation of the effectiveness of those actions, across sectors and scales. It can guide actions toward a sustainable future for people and nature, supporting the CBD’s vision. The adoption of the new Global Biodiversity Framework requires mainstreaming of biodiversity conservation into society. The Mitigation and Conservation Hierarchy places the Mitigation Hierarchy (1, avoid; 2, minimize; 3, restore; and 4, offset biodiversity impacts) within a broader framing encompassing all conservation actions. We illustrate its application by national governments, sub-national levels, companies, and individuals. This integrated framework supports the choice of actions to conserve and restore nature, and evaluation of their effectiveness, across sectors and scales.