F. W. Kiefer

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The newly identified liver- and fat-derived hormone, betatrophin, has recently been linked to insulin resistance and pancreatic beta cell growth in mice. These preclinical findings have suggested betatrophin as a potential candidate for novel glucose-lowering treatment concepts involving beta cell regeneration. However, the role of betatrophin in human(More)
BACKGROUND/AIMS Obesity is associated with a low-grade inflammation, insulin resistance, and macrophage infiltration of adipose tissue. The role of CC chemokines and their respective receptors in human adipose tissue inflammation remains to be determined. METHODS sc and visceral adipose tissue of obese patients (body mass index 53.1 +/- 11.3 kg/m(2))(More)
Obesity is associated with a chronic low-grade inflammation characterized by macrophage infiltration of adipose tissue (AT) that may underlie the development of insulin resistance and type 2 diabetes. Osteopontin (OPN) is a multifunctional protein involved in various inflammatory processes, cell migration, and tissue remodeling. Because these processes(More)
OBJECTIVE Obesity is associated with a state of chronic low-grade inflammation mediated by immune cells that are primarily located to adipose tissue and liver. The chronic inflammatory response appears to underlie obesity-induced metabolic deterioration including insulin resistance and type 2 diabetes. Osteopontin (OPN) is an inflammatory cytokine, the(More)
Osteopontin (OPN) is highly up-regulated in adipose tissue in human and murine obesity and has been recently shown to be functionally involved in the pathogenesis of obesity-induced adipose tissue inflammation and associated insulin resistance in mice. OPN is a protein with multiple functions and acts as a chemokine and an inflammatory cytokine through a(More)
Promoting brown adipose tissue (BAT) formation and function may reduce obesity. Recent data link retinoids to energy balance, but a specific role for retinoid metabolism in white versus brown fat is unknown. Retinaldehyde dehydrogenases (Aldhs), also known as aldehyde dehydrogenases, are rate-limiting enzymes that convert retinaldehyde (Rald) to retinoic(More)
Although obesity traditionally has been considered a condition of low risk for osteoporosis, this classic view has recently been questioned. The aim of this study was to assess bone microarchitecture and turnover in a mouse model of high-fat diet-induced obesity. Seven-week-old male C57BL/6J mice (n = 18) were randomized into 3 diet groups. One third (n =(More)
Obesity is strongly associated with the development of non-alcoholic fatty liver disease (NAFLD). The cytokine osteopontin (OPN) was recently shown to be involved in obesity-induced adipose tissue inflammation and reduced insulin response. Accumulating evidence links OPN to the pathogenesis of NAFLD. Here we aimed to identify the role of OPN in(More)
OBJECTIVE Infiltration by macrophages is a hallmark of obesity-related adipose tissue (AT) inflammation that is tightly linked to insulin resistance. Although CD11c+ AT macrophages (ATMs) have recently been shown to promote inflammation in obese mice, the knowledge on phenotype and function of different ATM populations is still very limited. This study(More)
Recent data link vitamin A and its retinoid metabolites to the regulation of adipogenesis, insulin sensitivity, and glucose homeostasis. Retinoid metabolism is tightly controlled by an enzymatic network in which retinaldehyde dehydrogenases (Aldh1-3) are the rate-limiting enzymes that convert retinaldehyde to retinoic acid. Aldh1a1-deficient mice are(More)