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Takeda G protein-coupled receptor 5 (TGR5) agonists induce systemic release of glucagon-like peptides (GLPs) from intestinal L cells, a potentially therapeutic action against metabolic diseases such as nonalcoholic steatohepatitis (NASH), nonalcoholic fatty liver disease (NAFLD), and Type 2 diabetes. Historically, TGR5 agonist use has been hindered by side effects, including inhibition of gallbladder emptying. Here, we characterize RDX8940, a novel, orally administered TGR5 agonist designed to have minimal systemic effects and investigate its activity in mice fed a Western diet, a model of NAFLD and mild insulin resistance. Agonist activity, binding selectivity, toxicity, solubility, and permeability of RDX8940 were characterized in standard in vitro models. RDX8940 pharmacokinetics and effects on GLP secretion, insulin sensitivity, and liver steatosis were assessed in C57BL/6 mice fed normal or Western diet chow and given single or repeated doses of RDX8940 or vehicle, with or without dipeptidyl peptidase-4 (DPP4) inhibitors. Gallbladder effects were assessed in CD-1 mice fed normal chow and given RDX8940 or a systemic TGR5 agonist or vehicle. Our results showed that RDX8940 is minimally systemic, potent, and selective, and induces incretin (GLP-1, GLP-2, and peptide YY) secretion. RDX8940-induced increases in plasma active GLP-1 (aGLP-1) levels were enhanced by repeated dosing and by coadministration of DPP4 inhibitors. RDX8940 increased hepatic exposure to aGLP-1 without requiring coadministration of a DPP4 inhibitor. In mice fed a Western diet, RDX8940 improved liver steatosis and insulin sensitivity. Unlike systemic TGR5 agonists, RDX8940 did not inhibit gallbladder emptying. These results indicate that RDX8940 may have therapeutic potential in patients with NAFLD/NASH.NEW & NOTEWORTHY Takeda G protein-coupled receptor 5 (TGR5) agonists have potential as a treatment for nonalcoholic steatohepatitis and nonalcoholic fatty liver disease (NAFLD) but have until now been associated with undesirable side effects associated with systemic TGR5 agonism, including blockade of gallbladder emptying. We demonstrate that RDX8940, a potent, selective, minimally systemic oral TGR5 agonist, improves liver steatosis and insulin sensitivity in a mouse model of NAFLD and does not inhibit gallbladder emptying in mice.

Lung cancer is the leading cause of cancer death in women in the United States. Prospective randomized lung screening trials suggest a greater lung cancer mortality benefit from screening women compared with men.Do the United States Preventative Services Task Force (USPSTF) lung screening guidelines that are based solely on age and smoking history contribute to sex disparities in eligibility, and if so, does the use of the PLCOm2012 risk prediction model that is based on 11 predictors of lung cancer reduce sex disparities?This retrospective analysis of 883 lung cancer cases in the Chicago Race Eligibility for Screening Cohort (CREST) determined the sensitivity of USPSTF vs PLCOm2012 eligibility criteria, stratified according to sex. For comparisons vs the USPSTF 2013 and the recently published USPSTF 2021 (released March 9, 2021) eligibility criteria, the PLCOm2012 model was used with risk thresholds of ≥ 1.7%/6 years (6y) and ≥ 1.0%/6y, respectively.The sensitivities for screening by the USPSTF 2013 were 46.7% for women and 64.6% for men (P = .003) and by the USPSTF 2021 were 56.8% and 71.8%, respectively (P = .02). In contrast, the PLCOm2012 ≥ 1.7%/6y sensitivities were 64.6% and 70.4%, and the PLCOm2012 ≥ 1.0%/6y sensitivities were 77.4% and 82.4%. The PLCOm2012 differences in sensitivity using ≥ 1.7%/6y and ≥ 1.0%/6y thresholds between women and men were nonsignificant (both, P = .07). Compared with men, women were more likely to be ineligible according to the USPSTF 2021 criteria because their smoking exposures were 20 pack-years (22.8% vs 14.8%; ORAlthough the USPSTF 2021 eligibility criteria are more sensitive than the USPSTF 2013 guidelines, sex disparities in eligibility remain. Adding the PLCOm2012 risk prediction model to the USPSTF guidelines would improve sensitivity and attenuate sex disparities.

Despite the increasing proportion of women in U.S. medical schools, there are relatively few women in leadership positions, and a number of recent publications have highlighted many factors that could contribute to gender inequity and inequality in medicine. The Association of Pulmonary, Critical Care, and Sleep Division Directors, an organization of Division Directors from across the United States, convened a workshop to review data and obtain input from leaders on the state of gender equity in our field. The workshop identified a number of factors that could contribute to gender inequality and inequity: gender climate (including implicit and perceived biases); disproportionate family responsibilities; lack of women in leadership positions; poor retention of women; and lack of gender equality in compensation. The panel members developed a roadmap of concrete recommendations for societies, leaders, and individuals that should promote gender equity to achieve gender equality and improve retention of women in the field of pulmonary, critical care, and sleep medicine.

Bile acid signaling and metabolism in the gastrointestinal tract have wide-ranging influences on systemic disease. G protein-coupled bile acid receptor 1 (GPBAR1, TGR5) is one of the major effectors in bile acid sensing, with demonstrated influence on metabolic, inflammatory, and proliferative processes. The pharmacologic utility of TGR5 agonists has been limited by systemic target-related effects such as excessive gallbladder filling and blockade of gallbladder emptying. Gut-restricted TGR5 agonists, however, have the potential to avoid these side effects and consequently be developed into drugs with acceptable safety profiles. We describe the discovery and optimization of a series of gut-restricted TGR5 agonists that elicit a potent response in mice, with minimal gallbladder-related effects. The series includes 12 (TGR5 EC50: human, 143 nM; mouse, 1.2 nM), a compound with minimal systemic availability that may have therapeutic value to patients with type 2 diabetes mellitus, nonalcoholic steatohepatitis...

Targeting glycosphingolipid synthesis has emerged as a novel approach for treating metabolic diseases. 32 (EXEL-0346) represents a new class of glucosylceramide synthase (GCS) inhibitors. This report details the elaboration of hit 8 with the goal of achieving and maintaining maximum GCS inhibition in vivo. 32 inhibited GCS with an IC(50) of 2 nM and achieved maximum hepatic GCS inhibition after four or five daily doses in rodents. Robust improvements in glucose tolerance in DIO mice and ZDF rats were observed after 2 weeks of q.d. dosing. Four weeks of dosing resulted in decreased plasma triglycerides and reduced hepatic fat deposition. Thus, 32 provides insight into the amount of metabolic regulation that can be restored following achievement of maximal target knockdown.

A novel series of potent inhibitors of glucosylceramide synthase are described. The optimization of biochemical and cellular potency as well as ADME properties led to compound 23c. Broad tissue distribution was obtained following oral administration to mice. Thus 23c could be another useful tool compound for studying the effects of GCS inhibition in vitro and in vivo.

Untersucht werden 29 Nitrosylkomplexe, wobei eine Beziehung zwischen der Bindungsenergie der Nitrosylgruppe und der Elektronendichte dieser Gruppe besteht.

The dihydrate of diborane has been prepared by the reaction of diborane with water at –130°.