Design, Synthesis and in Vitro Tumor Cytotoxicity Evaluation of 3,5-Diamino-N-substituted Benzamide Derivatives as Novel GSK-3β Small Molecule Inhibitors

Synthesis and biological evaluation of resveratrol amide derivatives as selective COX-2 inhibitors

Selective COX-2 inhibitors have been considered to be reliable alternatives to tNSAIDs, but most of them were withdrawn from the market due to their risk of heart attack and stroke. Therefore, it is urgent to develop a new type of selective COX-2 inhibitor with high efficiency and low toxicity. Inspired by the cardiovascular protection, and anti-inflammatory activity of resveratrol, we synthesized 38 resveratrol amide derivatives and evaluated their COX-1/COX-2 inhibitory activities. Compounds 8a, 6a, 8c and 13c showed important inhibitory activity against COX-2 (IC₅₀ = 0.42-2.54 μM) with definite selectivity (SI = 48-83). Molecular docking study demonstrated that these compounds partially entered the 2°-pocket of the COX-2 active site and interacted with the amino acid residues responsible for the COX-2 selectivity, which was in a similar orientation and binding interactions to rofecoxib. Further anti-inflammatory activity evaluation in vivo of these active compounds revealed that compound 8a showed no gastric ulcer toxicity, and displayed evident anti-inflammatory effect (45.95% inhibition of edema) with three oral doses of 50 mg/kg, which is worthy of further study. Moreover, compounds 6a and 8c also exhibited superior gastric safety profiles compared to the reference drugs celecoxib and indomethacin.

Glycogen Synthase Kinase 3 (GSK3): Its Role and Inhibitors

Glycogen Synthase Kinase 3 (GSK3) is one of the Serine/Threonine protein kinases, which has gained a lot of attention for its role in a variety of pathways. It has two isoforms, GSK3α and GSK3β. However, GSK3β is highly expressed in different areas of the brain and has been implicated in Alzheimer's disease as it is involved in tau phosphorylation. Due to its high specificity concerning substrate recognition, GSK3 has been considered as an important target. In the last decade, several GSK3 inhibitors have been reported and two molecules are in clinical trials. This review collates the information published in the last decade about the role of GSK3 in Alzheimer's disease and progress in the development of its inhibitors. Using this collated information, medicinal chemists can strategize and design novel GSK3 inhibitors that could be useful in the treatment of Alzheimer's disease.

Targeting GSK3 and Associated Signaling Pathways Involved in Cancer

Glycogen synthase kinase 3 (GSK-3) is a serine/threonine (S/T) protein kinase. Although GSK-3 originally was identified to have functions in regulation of glycogen synthase, it was subsequently determined to have roles in multiple normal biochemical processes as well as various disease conditions. GSK-3 is sometimes referred to as a moonlighting protein due to the multiple substrates and processes which it controls. Frequently, when GSK-3 phosphorylates proteins, they are targeted for degradation. GSK-3 is often considered a component of the PI3K/PTEN/AKT/GSK-3/mTORC1 pathway as GSK-3 is frequently phosphorylated by AKT which regulates its inactivation. AKT is often active in human cancer and hence, GSK-3 is often inactivated. Moreover, GSK-3 also interacts with WNT/β-catenin signaling and β-catenin and other proteins in this pathway are targets of GSK-3. GSK-3 can modify NF-κB activity which is often expressed at high levels in cancer cells. Multiple pharmaceutical companies developed small molecule inhibitors to suppress GSK-3 activity. In addition, various natural products will modify GSK-3 activity. This review will focus on the effects of small molecule inhibitors and natural products on GSK-3 activity and provide examples where these compounds were effective in suppressing cancer growth.