betadex and Obesity

Obesity has become a worldwide health crisis and is associated with a plethora of comorbidities. The multi-organ effects of obesity have been linked to ectopic lipid accumulation. Thus, there is an urgent need to tackle the obesity crisis by developing effective lipid-lowering therapies. 2-hydroxypropyl-β-Cyclodextrin (2HP-β-CD) has been previously shown to reduce lysosomal cholesterol accumulation in a murine model of Niemann Pick Type C (NPC) disease. Using a murine model of Western diet-induced obesity (DIO), we report the effects of 2HP-β-CD in counteracting weight gain, expansion of adipose tissue mass and ectopic lipid accumulation. Interestingly, DIO caused intracellular storage of neutral lipids in hepatic tissues and of phospholipids in kidneys, both of which were prevented by 2HP-β-CD. Importantly, this report brings attention to the nephrotoxic effects of 2HP-β-CD: renal tubular damage, inflammation and fibrosis. These effects may be overlooked, as they are best appreciated upon assessment of renal histology.

Topics: Animals; beta-Cyclodextrins; Cholesterol; Diet, Western; Disease Models, Animal; Hypolipidemic Agents; Kidney; Kidney Diseases; Liver; Male; Mice; Mice, Inbred C57BL; Obesity; Phospholipids; Triglycerides

Determining how obesity affects function in human myometrial arteries, to help understand why childbirth has poor outcomes in obese women.. Myometrial arteries were studied from 84 biopsies. Contraction (vasopressin and U-46619) and relaxation (carbachol, bradykinin, SNAP) was assessed using wire myography. eNOS activity was assessed using L-NAME. Cholesterol was reduced using methyl-β-cyclodextrin to determine whether it altered responses. Differences in endothelial cell intracellular Ca. The effects of BMI on relaxation were agonist specific and very marked; all vessels, irrespective of BMI, relaxed to bradykinin but 0% of vessels (0/13) from obese women relaxed to carbachol, compared to 59% (10/17) from normal weight women. Cholesterol-lowering drugs did not restore carbachol responses (n = 6). All vessels, irrespective of BMI, relaxed when NO was directly released by SNAP (n = 19). Inhibition of eNOS with L-NAME had a significant effect in normal but not overweight/obese vessels. Compared to bradykinin, a lower proportion of endothelial cells responded to carbachol and the amplitude of the calcium response was significantly less, in all vessels. Furthermore, a significantly lower proportion of endothelial cells responded to carbachol in the overweight/obese group compared to control. In contrast to relaxation, the effect of contractile agonists was unchanged with increasing BMI.. The ability of human myometrial arteries to relax is significantly impaired with obesity, and our data suggest this is due to a deficit in endothelial calcium signalling. This inability to recover following compression during contractions, might contribute to poor labours in obese women.

Topics: 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; Adult; Arginine Vasopressin; Arteries; beta-Cyclodextrins; Bradykinin; Calcium Signaling; Carbachol; Endothelial Cells; Female; Humans; Myometrium; NG-Nitroarginine Methyl Ester; Obesity; Obstetric Labor Complications; Pregnancy; S-Nitroso-N-Acetylpenicillamine; Uterine Contraction

Associations between obesity, diabetes type II, and steatosis have long been recognized. However, a pharmacotherapy that acts in a multifactorial manner controlling the interactions between these conditions is not available. A variety of natural plants, functional fatty acids, and other natural dietary compounds have been used in various anti-obesity products. We investigated the effects of oral administration of an antioxidant carotenoid pigment Bixin and Bixin: β-Cyclodextrin in an obese murine model. C57BL/6 male mice (4-5 weeks) received standard diet (2.18 kcal per 1 g) (CT) and high-fat diet (4.38 kcal per 1 g) (CT/OB, BIX and BIX/βCD) (n = 10 per group). After 16 weeks, the BIX and BIX/βCD were treated by gavage (100 μL day-1) for six weeks, with water (CT and CT/OB groups) and (50 mg kg-1 day-1), Bixin (BIX group) or Bix: β-CD (BIX/βCD). Body weight, Lee's Index, adiposity, CHT, TG, CHT/HDL-c, glucose levels (metabolic markers) and, liver markers (AST and ALT) were determined. All metabolic and liver parameters exhibited down-regulation after oral administration of BIX and BIX/βCD. Particularly relevant was Lee's Index and adiposity in BIX- and BIX/βCD-treated groups (339.18 g/cm -BIX and 327.58 g/cm -BIX/βCD vs. 360.68 g/cm -CT/OB animals), this finds associated with the insulin sensitivity test, showed a clear association between reduction of adipose tissue and decrease of peripherical insulin resistant. In conclusion, our study suggested that the oral administration of the Bixin and Bix: β-CD inclusion compound improved the metabolic parameters evaluate in obese mice, being more palatable and hepatoprotective.

Topics: 3T3-L1 Cells; Adipocytes; Adiposity; Animals; beta-Cyclodextrins; Biomarkers; Blood Glucose; Carotenoids; Diet, High-Fat; Disease Models, Animal; Dose-Response Relationship, Drug; Fatty Liver; Glucose Metabolism Disorders; Hypoglycemic Agents; Hypolipidemic Agents; Lipids; Liver; Male; Mice; Mice, Inbred C57BL; Obesity; Time Factors

Insulin stimulates glucose uptake in adult skeletal muscle by promoting the translocation of GLUT4 glucose transporters to the transverse tubule (T-tubule) membranes, which have particularly high cholesterol levels. We investigated whether T-tubule cholesterol content affects insulin-induced glucose transport. Feeding mice a high-fat diet (HFD) for 8 wk increased by 30% the T-tubule cholesterol content of triad-enriched vesicular fractions from muscle tissue compared with triads from control mice. Additionally, isolated muscle fibers (flexor digitorum brevis) from HFD-fed mice showed a 40% decrease in insulin-stimulated glucose uptake rates compared with fibers from control mice. In HFD-fed mice, four subcutaneous injections of MβCD, an agent reported to extract membrane cholesterol, improved their defective glucose tolerance test and normalized their high fasting glucose levels. The preincubation of isolated muscle fibers with relatively low concentrations of MβCD increased both basal and insulin-induced glucose uptake in fibers from controls or HFD-fed mice and decreased Akt phosphorylation without altering AMPK-mediated signaling. In fibers from HFD-fed mice, MβCD improved insulin sensitivity even after Akt or CaMK II inhibition and increased membrane GLUT4 content. Indinavir, a GLUT4 antagonist, prevented the stimulatory effects of MβCD on glucose uptake. Addition of MβCD elicited ryanodine receptor-mediated calcium signals in isolated fibers, which were essential for glucose uptake. Our findings suggest that T-tubule cholesterol content exerts a critical regulatory role on insulin-stimulated GLUT4 translocation and glucose transport and that partial cholesterol removal from muscle fibers may represent a useful strategy to counteract insulin resistance.

Topics: Animals; Anticholesteremic Agents; beta-Cyclodextrins; Biological Transport; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Cells, Cultured; Cholesterol; Glucose; Glucose Transporter Type 4; Hypoglycemic Agents; Insulin; Insulin Resistance; Male; Membrane Transport Modulators; Mice, Inbred C57BL; Muscle Fibers, Skeletal; Obesity; Phosphorylation; Protein Kinase Inhibitors; Protein Processing, Post-Translational; Proto-Oncogene Proteins c-akt; Ryanodine Receptor Calcium Release Channel

We investigated whether primary hypercholesterolaemia per se affects glucose homeostasis and insulin secretion in low-density lipoprotein receptor knockout mice (LDLR(-/-)). Glucose plasma levels were increased and insulin decreased in LDLR(-/-) compared to the wild-type mice. LDLR(-/-) mice presented impaired glucose tolerance, but normal whole body insulin sensitivity. The dose-response curve of glucose-stimulated insulin secretion was shifted to the right in LDLR(-/-) islets. Significant reductions in insulin secretion in response to l-leucine or 2-ketoisocaproic acid were also observed in LDLR(-/-). Islet morphometric parameters, total insulin and DNA content were similar in both groups. Glucose uptake and oxidation were reduced in LDLR(-/-) islets. Removal of cholesterol from LDLR(-/-) islets corrected glucose-stimulated insulin secretion. These results indicate that enhanced membrane cholesterol content due to hypercholesterolaemia leads to a lower insulin secretion and glucose intolerance without affecting body insulin sensitivity. This represents an additional risk factor for diabetes and atherosclerosis in primary hypercholesterolaemia.

Topics: Animals; beta-Cyclodextrins; Cholesterol; Dietary Fats; Female; Glucose; Glucose Tolerance Test; Homeostasis; Hypercholesterolemia; Insulin; Insulin Secretion; Islets of Langerhans; Leucine; Lipids; Male; Mice; Mice, Knockout; Obesity; Oxidation-Reduction; Receptors, LDL