Patients who manifest both binge eating and purging behaviour are at higher risk of substance use which may have important treatment implications.

No abstract

Liposomes are nanocarriers that deliver the payloads at the target site, leading to therapeutic drug concentrations at the diseased site and reduced toxic effects in healthy tissues. Several approaches have been used to enhance the ability of the nanocarrier to target the specific tissues, including ligand-targeted liposomes and stimuli-responsive liposomes. Ligand-targeted liposomes exhibit higher uptake by the target tissue due to the targeting ligand attached to the surface, while, the stimuli-responsive liposomes do not release their cargo unless they expose to an endogenous or exogenous stimulant at the target site. In this review, we mainly focus on the liposomes that are responsive to pathologically increased levels of enzymes at the target site. Enzyme-responsive liposomes release their cargo upon contact with the enzyme through several destabilization mechanisms: a) structural perturbation in the lipid bilayer, b) removal of a shielding polymer from the surface and increased cellular uptake, c) cleavage of a lipopeptide or lipopolymer incorporated in the bilayer, and d) activation of a prodrug in the liposomes.

Transplanting human gut microbiotas into germ-free (GF) mice is a popular approach to disentangle cause-and-effect relationships between enteric microbes and disease. Algorithm development has enabled sequence variant (SV) identification from 16S rRNA gene sequence data. SV analyses can identify which donor taxa colonize recipient GF mice, and how SV abundance in humans is replicated in these mice. Fecal microbiotas from 8 human subjects were used to generate 77 slurries, which were transplanted into 153 GF mice. Strong correlations between fecal and slurry microbial communities were observed; however, only 42.15 ± 9.95% of SVs successfully transferred from the donor to the corresponding recipient mouse. Firmicutes had a particularly low transfer rate and SV abundance was poorly correlated between donor and recipient pairs. Our study confirms human fecal microbiotas colonize formerly GF mice, but the engrafted community only partially resembles the input human communities. Our findings emphasize the importance of reporting a standardized transfer rate and merit the exploration of other animal models or in silico tools to understand the relationships between human gut microbiotas and disease.

No abstract

Roux-en-Y Gastric Bypass (RYGB) surgery is one of the most effective approaches for the treatment of severe obesity. Despite substantial weight loss following RYGB, a considerable proportion of patients experience weight regain or insufficient weight loss. The proposed research aimed to investigate the role of the gut microbiota in weight regain or suboptimal weight loss following RYGB. The gut microbiota composition in post-RYGB patients who experienced successful weight loss (SWL, n=6), post-RYGB patients who experienced poor weight loss (PWL, n=6), and non-surgical controls (NSC, n=6) who were age-and BMImatched to the SWL group (NSC, n=6) were characterized through 16S rRNA gene sequencing. To further investigate the impact of the gut microbiota on weight profile, human fecal samples were transplanted into antibiotic-treated mice through oral gavage. Food intake and body weight were measured at weekly intervals for a month. At five weeks following colonization mice were randomly switched to a western diet or maintained on a normal diet. The results showed that Lactobacillales, Enterobacteriales, and Verrucomicrobials were enriched in both surgical groups compared to the NSC group. No significant difference was observed in the gut microbiota composition between PWL and SWL patients. However, transfer of the gut microbiota from human patients into antibiotic-treated mice resulted in significantly greater weight gain in PWL recipient mice compared to SWL recipient mice at four weeks following colonization (15.03±2.59% versus 7.88±1.28%, F(2,41)=4.01 p=0.026). We found that Barnesiella, Gordonibacter, Parasutterella, Clostridium cluster XVIa were effectively transferred from humans to mice and were associated with weight gain in recipient mice. Interestingly,

Obesity and metabolic surgery (OMS) leads to several metabolic improvements, which often occur prior to substantial weight loss. Therefore, other factors in addition to weight loss contribute to the metabolic benefits. This literature review offers an overview of studies investigating bile acids (BAs) and their metabolic effects after OMS. Rearrangement of enterohepatic circulation, changes in BA synthesis, BA conjugation, intestinal reabsorption, and alterations in the gut microbiota are potential mechanisms for altered BA profiles after surgery. Increased BA levels are associated with improved glucose homeostasis and lipid profiles, which are mediated by two major receptors: the Transmembrane G-protein Coupled Receptor and the Farnesoid X Receptor. Therefore, pharmacological manipulation of BAs and their receptors may be viable targets for less invasive obesity treatment.

Anorexia nervosa (AN) is a psychiatric disorder that presents with profound weight dysregulation, metabolic disturbances, and an abnormal composition of gut microbial communities. As the intestinal microbiota can influence host metabolism, the impact of enteric microbial communities from patients with AN on host weight and adiposity was investigated. Germ-free (GF) mice were colonized with fecal microbiotas from either patients with AN (n = 4) prior to inpatient treatment (AN T1, n = 50 recipient mice), the same 4 patients following clinical renourishment (AN T2, n = 53 recipient mice), or age- and sex-matched non-AN controls (n = 4 human donors; non-AN, n = 50 recipient mice). Biological and fecal microbiota data were analyzed with linear mixed-effects models. Body weight did not differ significantly between AN recipient mice (T1 and T2) and non-AN recipient mice following 4 weeks of colonization. Enteric microbiotas from recipient mice colonized with AN T1 and AN T2 fecal microbiotas were more similar to each other compared with enteric microbiotas from non-AN recipient mice. Specific bacterial families in the Actinobacteria, Bacteroidetes, and Firmicutes phyla were significantly associated with body weight, fat mass, and cecum weight irrespective of the donor group. These data suggest that body weight, fat mass, and cecum weight of colonized GF mice are associated with human fecal microbes and independent of donor AN status, although additional analyses with larger cohorts are warranted.