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The endocannabinoidome (expanded endocannabinoid system, eCBome)-gut microbiome (mBIome) axis plays a fundamental role in the control of energy intake and processing. The liver-expressed antimicrobial peptide 2 (LEAP2) is a recently identified molecule acting as an antagonist of the ghrelin receptor and hence a potential effector of energy metabolism, also at the level of the gastrointestinal system. Here we investigated the role of the eCBome-gut mBIome axis in the control of the expression of LEAP2 in the liver and, particularly, the intestine. We confirm that the small intestine is a strong contributor to the circulating levels of LEAP2 in mice, and show that: (1) intestinal Leap2 expression is profoundly altered in the liver and small intestine of 13 week-old germ-free (GF) male mice, which also exhibit strong alterations in eCBome signaling; fecal microbiota transfer (FMT) from conventionally raised to GF mice completely restored normal Leap2 expression after 7 days from this procedure; in 13 week-old female GF mice no significant change was observed; (2) Leap2 expression in organoids prepared from the mouse duodenum is elevated by the endocannabinoid noladin ether, whereas in human Caco-2/15 epithelial intestinal cells it is elevated by PPARγ activation by rosiglitazone; (3) Leap2 expression is elevated in the ileum of mice with either high-fat diet—or genetic leptin signaling deficiency—(i.e., ob/ob and db/db mice) induced obesity. Based on these results, we propose that LEAP2 originating from the small intestine may represent a player in eCBome- and/or gut mBIome-mediated effects on food intake and energy metabolism. [ABSTRACT FROM AUTHOR]

Diet-induced obesity contributes to the development of type 2 diabetes, insulin resistance, metabolic inflammation, oxidative and endoplasmic reticulum (ER) stress. Overall, obesity is associated with deviations in the composition and functionality of the gut microbiota. There are many divergent findings regarding the link between the excessive intake of certain dietary components (i.e., fat and sugar) and obesity development. We therefore investigated the effect of specific diets, with a different content of sugar and fat, in promoting obesity and related comorbidities as well as their impact on microbial load and gut microbiota composition/diversity. C57BL/6J mice were fed either a low-sugar, low-fat control diet (CT), a high-sugar diet (HS), a high-fat, high-sugar diet (HF/HS), or a high-fat diet (HF) for 8 wk. The impact of the different diets on obesity, glucose metabolism, inflammation, and oxidative and ER stress was determined. Diet-induced changes in the gut microbiota composition and density were also analyzed. HF diet-fed mice showed the highest body weight and fat mass gains and displayed the most impaired glucose and insulin profiles. HS, HF/HS, and HF diets differently affected hepatic cholesterol content and mRNA expression of several markers associated with immune cells, inflammation, oxidative and ER stress in several organs/tissues. In addition, HF diet feeding resulted in a decreased microbial load at the end of the experiment. When analyzing the gut microbiota composition, we found that HS, HF/HS, and HF diets induced specific changes in the abundance of certain bacterial taxa. This was not associated with a specific change in systemic inflammatory markers, but HS mice exhibited higher FGF21 plasma levels compared with HF diet-fed mice. Taken together, our results highlight that dietary intake of different macronutrients distinctively impacts the development of an obese/diabetic state and the regulation of metabolic inflammation in specific organs. We propose that these differences are not only obesity-driven but that changes in the gut microbiota composition may play a key role in this context. NEW & NOTEWORTHY To our knowledge, this study is the first to demonstrate that dietary macronutrients (i.e., sugar and fat) have an impact on fecal bacterial cell counting and quantitative microbiome profiling in mice. Yet, we demonstrate that dietary fat is the determining factor to promote obesity and diabetes progression, and local inflammation in different body sites. These observations can help to disentangle the conundrum of the detrimental effects of fat and sugar in our dietary habits.

Objective: To fulfil an unmet therapeutic need for treating type 2 diabetes by developing an innovative oral drug delivery nanosystem increasing the production of glucagon-like peptide-1 (GLP-1) and the absorption of peptides into the circulation., Design: We developed a nanocarrier for the oral delivery of peptides using lipid-based nanocapsules. We encapsulated the GLP-1 analogue exenatide within nanocapsules and investigated in vitro in human L-cells (NCl-H716) and murine L-cells (GLUTag cells) the ability of the nanosystem to trigger GLP-1 secretion. The therapeutic relevance of the nanosystem in vivo was tested in high-fat diet (HFD)-induced diabetic mice following acute (one administration) or chronic treatment (5 weeks) in obese and diabetic mice., Results: We demonstrated that this innovative nanosystem triggers GLP-1 secretion in both human and murine cells as well as in vivo in mice. This strategy increases the endogenous secretion of GLP-1 and the oral bioavailability of the GLP-1 analogue exenatide (4% bioavailability with our nanosystem).The nanosystem synergizes its own biological effect with the encapsulated GLP-1 analogue leading to a marked improvement of glucose tolerance and insulin resistance (acute and chronic). The chronic treatment decreased diet-induced obesity, fat mass, hepatic steatosis, together with lower infiltration and recruitment of immune cell populations and inflammation., Conclusion: We developed a novel nanosystem compatible with human use that synergizes its own biological effect with the effects of increasing the bioavailability of a GLP-1 analogue. The effects of the formulation were comparable to the results observed for the marketed subcutaneous formulation. This nanocarrier-based strategy represents a novel promising approach for oral peptide delivery in incretin-based diabetes treatment., Competing Interests: Competing interests: PDC is a co-founder of A-Mansia Biotech SA., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Electro optical absorption in hydrogenated amorphous silicon (proportional-Si:H)--morphous silicon carbonitride (proportional-SiCxNy) multilayers have been studied in two different planar multistacks waveguides. The waveguides were realized by plasma enhanced chemical vapour deposition (PECVD), a technology compatible with the standard microelectronic processes. Light absorption is induced at lambda = 1.55 microm through the application of an electric field which induces free carrier accumulation across the multiple insulator/semiconductor device structure. The experimental performances have been compared to those obtained through calculations using combined two-dimensional (2-D) optical and electrical simulations.