Insights from comparison of serum IgG4 between T2-eosinophilic asthma and eosinophilic granulomatosis with polyangiitis/idiopathic hypereosinophilic syndrome.

Objectives: Eosinophilic granulomatosis with polyangiitis (EGPA) and idiopathic hypereosinophilic syndrome (iHES) are systemic hypereosinophilic diseases largely overlapping. Type 2 (T2)-eosinophilic asthma is documented in 100% and 44-95% of EGPA and iHES patients, respectively, probably representing the beginning of the systemic eosinophilic disorders, as suggested by mepolizumab, effective in both asthma and EGPA/iHES. In this respect, there are no predictive biomarkers of progression from T2-eosinophilic asthma into EGPA/iHES.

ANCA-negative EGPA: only eosinophils without vasculitis? Insights from anti-T2 biologics.

The pathogenic role of p-ANCA in eosinophilic granulomatosis with polyangiitis (EGPA) is a long-standing matter of debate. In this work, we report our real-life experience with EGPA patients, treated with biologics targeting type 2 (T2)-eosinophilic inflammation (Mepolizumab, Benralizumab, Dupilumab). Interestingly, we observed EGPA extrarespiratory relapses only in p-ANCA-positive patients (2/5 cutaneous vasculitis, 3/5 constitutional symptoms), with new rise of p-ANCA and normal eosinophil blood count.

Mechanisms linking bariatric surgery to adipose tissue, glucose metabolism, fatty liver disease and gut microbiota.

Purpose: In the last 20 years, bariatric surgery has achieved an important role in translational and clinical research because of obesity comorbidities. Initially, a tool to lose weight, bariatric surgery now has been shown to be involved in several metabolic pathways.

Methods: We conducted a narrative review discussing the underlying mechanisms that could explain the impact of bariatric surgery and the relationship between obesity and adipose tissue, T2D, gut microbiota, and NAFLD.

The density of crown-like structures in epicardial adipose tissue could play a role in cardiovascular diseases.

Purpose: The visceral fat of patients affected by abdominal obesity is inflamed, and the main histopathologic feature is the high density of crown-like structures (CLS). Epicardial adipose tissue (EAT) is a visceral fat of paramount importance for its relationships with coronary vessels and myocardium. Its inflammation in patients with abdominal obesity could be of clinical relevance, but histopathological studies on CLS density in EAT are lacking.

A single-cell atlas of human and mouse white adipose tissue.

White adipose tissue, once regarded as morphologically and functionally bland, is now recognized to be dynamic, plastic and heterogenous, and is involved in a wide array of biological processes including energy homeostasis, glucose and lipid handling, blood pressure control and host defence. High-fat feeding and other metabolic stressors cause marked changes in adipose morphology, physiology and cellular composition, and alterations in adiposity are associated with insulin resistance, dyslipidemia and type 2 diabetes. Here we provide detailed cellular atlases of human and mouse subcutaneous and visceral white fat at single-cell resolution across a range of body weight.

Brown Fat Anatomy in Humans and Rodents.

The Brown Adipose Tissue (BAT) is composed by mitochondrial rich, multilocular adipocytes, in strict topographical and functional relation with vasculature and noradrenergic nerves. Brown adipocytes are able to dissipate energy to produce heat, in a process known as non-shivering thermogenesis. Due to its contribution to energy expenditure, BAT is intensely studied for its potential to counteract metabolic diseases such as obesity, type 2 diabetes, dyslipidemia and cardiovascular diseases.

Visceral fat inflammation and fat embolism are associated with lung's lipidic hyaline membranes in subjects with COVID-19.

Background: Preliminary data suggested that fat embolism could explain the importance of visceral obesity as a critical determinant of coronavirus disease-2019 (COVID-19).

Methods: We performed a comprehensive histomorphologic analysis of autoptic visceral adipose tissue (VAT), lungs and livers of 19 subjects with COVID-19 (COVID-19+), and 23 people without COVID-19 (controls). Human adipocytes (hMADS) infected with SARS-CoV-2 were also studied.

High-Fat Diet Impairs Mouse Median Eminence: A Study by Transmission and Scanning Electron Microscopy Coupled with Raman Spectroscopy.

Hypothalamic dysfunction is an initial event following diet-induced obesity, primarily involving areas regulating energy balance such as arcuate nucleus (Arc) and median eminence (ME). To gain insights into the early hypothalamic diet-induced alterations, adult CD1 mice fed a high-fat diet (HFD) for 6 weeks were studied and compared with normo-fed controls. Transmission and scanning electron microscopy and histological staining were employed for morphological studies of the ME, while Raman spectroscopy was applied for the biochemical analysis of the Arc-ME complex.

Gastric ghrelin cells in obese patients are hyperactive.

Background/objectives: Distribution and activity of ghrelin cells in the stomach of obese subjects are controversial.

Subjects/methods: We examined samples from stomachs removed by sleeve gastrectomy in 49 obese subjects (normoglycemic, hyperglycemic and diabetic) and quantified the density of ghrelin/chromogranin endocrine cells by immunohistochemistry. Data were compared with those from 13 lean subjects evaluated by gastroscopy.

A large proportion of mediastinal and perirenal visceral fat of Siberian adult people is formed by UCP1 immunoreactive multilocular and paucilocular adipocytes.

Many deleterious consequences for health of excessive fat accumulation are due to visceral fat. Browning of visceral fat is mainly cold dependent and has been proposed as a possible tool for future therapies of obesity and related disorders. In this paper, we studied the composition of mediastinal and perirenal visceral fat, collected at necropsy, of human adults that lived in Siberia, one of the coldest regions of the earth.