In silico designing, in vitro and in vivo evaluation of potential PPAR-γ agonists derived from aryl propionic acid scaffold.

Attributed to several side effects, especially on hepatic tissues and body weight, there is always an urge of innovation and upgrading in already existing medication being used in maintaining diabetic condition. Therefore, in the present work, forty-eight molecules derived from arylpropionic acid scaffold were synthesized and their evaluation against diabetes was carried out. The synthesis of these molecules attributed to excellent dock score displayed by all the structures performed against PPAR-γ receptor site. Subsequently, all the derivatives were primarily deduced for their antidiabetic potential by OGTT. The compounds that showed significant antidiabetic activity in OGT Test and also exhibited high dock scores were assessed further by in vitro PPAR transactivation assay to assure analogy between in vivo and in vitro studies. The antidiabetic activity of these active compounds was then evaluated on STZ induced diabetic model in vivo. The most active compounds were scrutinized for its effect on PPAR-γ gene expression and hepatotoxic effect. Finally, it was recapitulated that these derivatives can provide a new prospect towards the development of antidiabetic agents with fewer side effects.

Salt-sensitive phenotypes: A community-based exploratory study from northeastern India.

Background: Salt sensitivity is known to increase the risk of cardiovascular diseases in both normotensive and hypertensive subjects. The population in the northeastern region of India consumes excess dietary salt but their saltsensitive phenotype is not known. Methods: We did a community-based exploratory study using volunteers in the northeastern region of India to determine salt-sensitive (SS) and salt-resistant (SR) phenotypes. A total of 374 (206 normotensive and 168 hypertensive) subjects who gave informed consent were stabilized for salt with 7 days of a low-salt (2.9 g/day) diet followed by 7 days of a high-salt (15.2 g/day) diet. SS was defined as an increase of mean arterial blood pressure ≥9 mmHg after a high-salt diet. Results: We noted an increase in systolic blood pressure of 9.3 mmHg in normotensive subjects and 10.7 mmHg in hypertensive subjects, with a modest effect on diastolic blood pressure (6.9 mmHg in normotensive and 8.2 mmHg in hypertensive subjects) after a high-salt diet. Salt-sensitive phenotype was present in 40.8% of normotensive and 47.6% of hypertensive subjects. Resistance to introduction of high salt was observed in 43.7% of normotensive and 33.9% of hypertensive subjects. Consumption of extra salt (adjusted OR 1.99, 95% CI 1.25-3.18) was independently associated with salt sensitivity. Conclusion: Salt sensitivity was found in a large proportion of normotensive and hypertensive subjects. Restriction of salt intake could be an effective intervention to control hypertension among salt-sensitive subjects.

Novel benzenesulfonylureas containing thiophenylpyrazoline moiety as potential antidiabetic and anticancer agents.

In the present study a library of twenty six benzenesulfonylureas containing thiophenylpyrazoline moiety has been synthesized. All the compounds were docked against PPAR-γ target. Most of the compounds displayed higher dock score than standard drugs, glibenclamide and rosiglitazone. All the synthesized compounds were primarily evaluated for their antidiabetic effect by oral glucose tolerance test. Further assessment of antidiabetic potential of sixteen active compounds was then done on STZ induced diabetic model. The results of in vivo activity by both the methods were found to be consistent with each other as well as with docking studies. Change in body weight of STZ induced animals post treatment was also assessed at the end of study. In vitro PPAR-γ transactivation assay was performed on active compounds in order to validate docking results and the most active compound 3 k was also shown to elevate gene expression of PPAR-γ. Furthermore, the compounds were screened by National Cancer Institute, Bethesda for anticancer effect and two compounds 3h and 3 i were selected at one dose level since they exhibited sensitivity towards tumor cell lines (mainly melanoma).

Design, synthesis, in silico molecular docking and biological evaluation of novel oxadiazole based thiazolidine-2,4-diones bis-heterocycles as PPAR-γ agonists.

A library of novel 1,3,4-oxadiazole and 2-4-thiazolidinedione based bis-heterocycles 7 (a-r) has been synthesized which exhibited significant PPAR-γ transactivation and blood glucose lowering effect comparable with the standard drugs Pioglitazone and Rosiglitazone. Compounds 7m and 7r did not cause body weight gain and were found to be free from hepatotoxic and cardiotoxic side effects. Compounds 7m and 7r increased PPAR-γ gene expression by 2.10 and 2.00 folds, respectively in comparison to the standard drugs Pioglitazone (1.5 fold) and Rosiglitazone (1.0 fold). Therefore the compounds 7m and 7r may be considered as potential candidates for development of new antidiabetic agents.

Thiazolidine-2,4-diones derivatives as PPAR-γ agonists: synthesis, molecular docking, in vitro and in vivo antidiabetic activity with hepatotoxicity risk evaluation and effect on PPAR-γ gene expression.

A library of conjugates of chromones and 2,4-thiazolidinedione has been synthesized by Knoevenagel condensation followed by reduction using hydrogen gas and Pd/C as a catalyst. Compounds 5c and 5e were most effective in lowering the blood glucose level comparable to standard drug pioglitazone. Compound 5e exhibited potent PPAR-γ transactivation of 48.72% in comparison to pioglitazone (62.48%). All the molecules showed good glide score against the PPAR-γ target in molecular docking study. PPAR-γ gene expression was significantly increased by compound 5e (2.56-fold) in comparison to standard drug pioglitazone. Compounds 5e and 5c did not cause any damage to the liver and may be considered as promising candidates for the development of new antidiabetic agents.

Synthesis of novel 2-mercaptobenzoxazole based 1,2,3-triazoles as inhibitors of proinflammatory cytokines and suppressors of COX-2 gene expression.

A library of novel bis-heterocycles containing 2-mercaptobenzoxazole based 1,2,3-triazoles has been synthesized using click chemistry approach. The compound 4 exhibited the most potent in vivo anti-inflammatory activity with 66.66% and 61.11% inhibition in comparison to celecoxib which showed 72.22% and 65.55% inhibition after 3 h and 5 h respectively. The compounds 4 and 9 suppressed the COX-2 gene expression by 0.94 and 0.79 fold and exhibited a selective index (COX-1/COX-2) of 64.79 and 66.47 respectively in comparison to celecoxib (SI value of 75.56). The in silico molecular docking studies showed the interactions of these molecules with Tyr-59, Tyr-119 and Gly-121. When compared with the standard drug celecoxib, compounds 4, 5, 7, 9 and 16 did not cause any gastric ulceration.

Sulfur-containing angiotensin-converting enzyme inhibitor 3-thienylalanine-ornithyl-proline activates endothelial function and expression of genes involved in Renin-Angiotensin system.

Experiments were performed to elucidate the mechanism of action of a 7-day oral administration of the sulfur-containing angiotensin-converting enzyme (ACE) inhibitor 3-thienylalanine-ornithyl-proline (TOP; 10 mg/kg/d) on endothelial dysfunction and oxidative stress compared with that of captopril (control; 40 mg/kg/d) in spontaneously hypertensive rats. The differential expression of messenger RNA by real-time reverse-transcriptase-polymerase chain reaction and protein by Western blot analysis was assessed for the markers nicotinamide adenine dinucleotide phosphate oxidase, p22phox, endothelial nitric oxide (NO) synthase, and AT1 receptor. Furthermore, TOP-induced vascular relaxation was also investigated using rat aortic rings in an organ bath. TOP significantly downregulated both messenger RNA and protein expressions of p22phox and AT1 receptor; the latter facilitates vasoconstriction through angiotensin II. In addition, TOP upregulated endothelial NO synthase, thus enhancing the production of NO. Vascular studies revealed that TOP caused endothelium-dependent vasorelaxation. In conclusion, unlike the free sulfur in captopril, the thiophene ring in TOP may act as a better scavenger of free radicals. Therefore, TOP exerted more significant antihypertensive effects than captopril, not only through angiotensin-converting enzyme inhibition but also through more effective antioxidation, because the inherent thiophene moiety resulted in the enhanced production of NO.