Synthesis and therapeutic evaluation of pyridyl based novel mTOR inhibitors

Mango polyphenolics reduce inflammation in intestinal colitis-involvement of the miR-126/PI3K/AKT/mTOR axis in vitro and in vivo

This study sought to elucidate the mechanisms underlying the anti-inflammatory effect of mango (Mangifera Indica L.) polyphenolics containing gallic acid and gallotanins, and the role of the miR-126/PI3K/AKT/mTOR signaling axis in vitro and in vivo. Polyphenolics extracted from mango (var. Keitt) were investigated in lipopolysaccharide (LPS)-treated CCD-18Co cells. Rats received either a beverage with mango polyphenolics or a control beverage, and were exposed to three cycles of 3% dextran sodium sulfate (DSS) followed by a 2-wk recovery period. The mango extract (10 mg GAE/L) suppressed the protein expression of NF-κB, p-NF-κB, PI3K (p85β), HIF-1α, p70S6K1, and RPS6 in LPS-treated CCD-18Co cells. LPS reduced miR-126 expression, whereas, the mango extract induced miR-126 expression in a dose-dependent manner. The relationship between miR-126 and its target, PI3K (p85β), was confirmed by treating cells with miR-126 antagomiR where mango polyphenols reversed the effects of the antagomiR. In vivo, mango beverage protected against DSS-induced colonic inflammation (47%, P = 0.05) and decreased the Ki-67 labeling index in the central and basal regions compared to the control. Mango beverage significantly attenuated the expression of pro-inflammatory cytokines such as TNF-α, IL-1β, and iNOS at the mRNA and protein level. Moreover, the expression of PI3K, AKT, and mTOR was reduced, whereas, miR-126 was upregulated by the mango treatment. These results suggest that mango polyphenols attenuated inflammatory response by modulating the PI3K/AKT/mTOR pathway at least in part through upregulation of miRNA-126 expression both in vitro and in vivo; thus, mango polyphenolics might be relevant as preventive agents in ulcerative colitis. © 2016 Wiley Periodicals, Inc.

Comparison of anti-inflammatory mechanisms of mango (Mangifera Indica L.) and pomegranate (Punica Granatum L.) in a preclinical model of colitis

SCOPE

Tannin-rich fruits have been evaluated as alternative prevention strategies for colorectal cancer based on their anti-inflammatory properties. This study compared tannin-rich preparations from mango (rich in gallotannins) and pomegranate (rich in ellagitannins) in the dextran sodium sulfate-induced colitis model.

METHODS AND RESULTS

In rats, mango and pomegranate beverages decreased intestinal inflammation and the levels of pro-inflammatory cytokines in mucosa and serum. The mango beverage suppressed the ratio of phosphorylated/total protein expression of the IGF-1R-AKT/mTOR axis and downregulated mRNA expression of Igf1, Insr, and pik3cv. Pomegranate decreased p70S6K and RPS6, as well as Rps6ka2, Map2k2, and Mapk1 mRNA. In silico modeling indicated a high binding of docked of gallic acid to the catalytic domain of IGF-1R, which may suppress the activity of the enzyme. Ellagic acid docked effectively into the catalytic domains of both IGF-1R and EGFR. In vitro assays with lipopolysaccharide-treated CCD-18Co cells using polyphenolic extracts from each beverage, as well as pure compounds, corroborated the predictions made in silico.

CONCLUSION

Mango polyphenols inhibited the IGF-1R- AKT/mTOR axis, and pomegranate polyphenols downregulate the mTOR downstream pathway through reductions in ERK1/2. These results suggest that extracts rich in gallo- and ellagitannins act on different molecular targets in the protection against ulcerative colitis.

Salicylic acid derivatives: synthesis, features and usage as therapeutic tools

INTRODUCTION

In the field of medicinal chemistry, there is a growing interest in the use of small molecules. Although acetyl salicylic acid is well known for medical applications, little is known about other salicylic acid derivatives, and there is serious lack of data and information on the effects and biological evaluation that connect them.

AREAS COVERED

This review covers the synthesis and drug potencies of salicylic acid derivatives. After a brief overview of the information on salicylic acid and its features, a detailed review of salicylic acids as drugs and prodrugs, usage as cyclooxygenase inhibitors, properties in plants, synthesis and recent patents, is developed.

EXPERT OPINION

Salicylic acid research is still an important area and innovations continue to arise, which offer hope for new therapeutics in related fields. It is anticipated that this review will guide the direction of long-term drug/nutraceutical safety trials and stimulate ideas for future research.

Recent advances in the discovery of small molecule mTOR inhibitors

Mammalian target of rapamycin (mTOR) belongs to the atypical kinase family of phosphatidylinositol-3-kinase-related kinase and function as a master regulators of the switch between catabolic and anabolic metabolism. In the last decade mTOR has emerged as a therapeutic target for various diseases such as cancer, inflammation and metabolic disorders. mTOR plays a crucial role in the PI3K/AKT/PDK1 pathway. In this review we will provide an overview of both selective and nonselective mTOR inhibitors. Since rapamycin and rapalogs have been reviewed before, more emphasis has been placed on nonrapamycin-based small-molecule inhibitors and their modulation of mTOR selectivity. Recent efforts in obtaining mTOR-selective inhibitors have produced a range of compounds with more than 1000-fold selectivity over PI3K, but it is still a matter of debate whether an mTOR-selective inhibitor will be of more clinical significance over a PI3K/AKT/mTOR inhibitor.