Impact of drug distribution into adipose on tissue function: The cholesteryl ester transfer protein (CETP) inhibitor anacetrapib as a test case.

Anacetrapib is an inhibitor of cholesteryl ester transfer protein (CETP) previously under development as a lipid-modifying agent that reduces LDL-cholesterol and increases HDL-cholesterol in hypercholesterolemic patients. Anacetrapib demonstrates a long terminal half-life and accumulates in adipose tissue, which contributes to a long residence time of anacetrapib. Given our previous report that anacetrapib distributes into the lipid droplet of adipose tissue, we sought to understand whether anacetrapib affected adipose function, using a diet-induced obese (DIO) mouse model.

Dose-dependent effects of siRNA-mediated inhibition of SCAP on PCSK9, LDLR, and plasma lipids in mouse and rhesus monkey.

SREBP cleavage-activating protein (SCAP) is a key protein in the regulation of lipid metabolism and a potential target for treatment of dyslipidemia. SCAP is required for activation of the transcription factors SREBP-1 and -2. SREBPs regulate the expression of genes involved in fatty acid and cholesterol biosynthesis, and LDL-C clearance through the regulation of LDL receptor (LDLR) and PCSK9 expression.

Butyrate and propionate protect against diet-induced obesity and regulate gut hormones via free fatty acid receptor 3-independent mechanisms.

Short-chain fatty acids (SCFAs), primarily acetate, propionate, and butyrate, are metabolites formed by gut microbiota from complex dietary carbohydrates. Butyrate and acetate were reported to protect against diet-induced obesity without causing hypophagia, while propionate was shown to reduce food intake. However, the underlying mechanisms for these effects are unclear.

The glucagon receptor is involved in mediating the body weight-lowering effects of oxyntomodulin.

Oxyntomodulin (OXM) is a peptide secreted postprandially from the L-cells of the gut that has a weak affinity for both the glucagon-like peptide-1 receptor (GLP1R) and the glucagon receptor (GCGR). Peripheral administration of OXM in humans and rodents causes weight loss reducing food intake and increasing energy expenditure. It has been suggested that OXM modulates energy intake solely through GLP1R agonism.

Quantifying apoprotein synthesis in rodents: coupling LC-MS/MS analyses with the administration of labeled water.

Stable isotope tracer studies of apoprotein flux in rodent models present difficulties as they require working with small volumes of plasma. We demonstrate the ability to measure apoprotein flux by administering either (2)H- or (18)O-labeled water to mice and then subjecting samples to LC-MS/MS analyses; we were able to simultaneously determine the labeling of several proteolytic peptides representing multiple apoproteins. Consistent with relative differences reported in the literature regarding apoprotein flux in humans, we found that the fractional synthetic rate of apoB is greater than apoA1 in mice.

Effects of peripherally administered neuromedin U on energy and glucose homeostasis.

Neuromedin U (NMU) is a highly conserved peptide reported to modulate energy homeostasis. Pharmacological studies have shown that centrally administered NMU inhibits food intake, reduces body weight, and increases energy expenditure. NMU-deficient mice develop obesity, whereas transgenic mice overexpressing NMU become lean and hypophagic.

Discovery of pyrimidine carboxamides as potent and selective CCK1 receptor agonists.

A series of six-membered heterocycle carboxamides were synthesized and evaluated as cholecystokinin 1 receptor (CCK1R) agonists. A pyrimidine core proved to be the best heterocycle, and SAR studies resulted in the discovery of analog 5, a potent and structurally diverse CCK1R agonist.

2-Substituted piperazine-derived imidazole carboxamides as potent and selective CCK1R agonists for the treatment of obesity.

The discovery and structure-activity relationship of 1,2-diarylimidazole piperazine carboxamides bearing polar side chains as potent and selective cholecystokinin 1 receptor (CCK1R) agonists are described. Optimization of this series resulted in the discovery of isopropyl carboxamide 40, a CCK1R agonist with sub-nanomolar functional and binding activity as well as excellent potency in a mouse overnight food intake reduction assay.

Discovery of imidazole carboxamides as potent and selective CCK1R agonists.

High-throughput screening revealed diaryl pyrazole 3 as a selective albeit modest cholecystokinin 1 receptor (CCK1R) agonist. SAR studies led to the discovery and optimization of a novel class of 1,2-diaryl imidazole carboxamides. Compound 44, which was profiled extensively, showed good in vivo mouse gallbladder emptying (mGBE) and lean mouse overnight food intake (ONFI) reduction activities.