Current Medicinal Chemistry - Volume 30, Issue 28, 2023

Background: In the last few years, in silico tools, including drug repurposing coupled with structure-based virtual screening, have been extensively employed to look for anti-COVID-19 agents. Objective: The present review aims to provide readers with a portrayal of computational approaches that could be conducted more quickly and cheaply to novel anti-viral agents. Particular attention is given to docking-based virtual screening. Methods: The World Health Organization website was consulted to gain the latest information on SARS-CoV-2, its novel variants and their interplay with COVID-19 severity and treatment options. The Protein Data Bank was explored to look for 3D coordinates of SARS-CoV-2 proteins in their free and bound states, in the wild-types and mutated forms. Recent literature related to in silico studies focused on SARS-CoV-2 proteins was searched through PubMed. Results: A large amount of work has been devoted thus far to computationally targeting viral entry and searching for inhibitors of the S-protein/ACE2 receptor complex. Another large area of investigation is linked to in silico identification of molecules able to block viral proteases -including Mpro- thus avoiding maturation of proteins crucial for virus life cycle. Such computational studies have explored the inhibitory potential of the most diverse molecule databases (including plant extracts, dietary compounds, FDA approved drugs). Conclusion: More efforts need to be dedicated in the close future to experimentally validate the therapeutic power of in silico identified compounds in order to catch, among the wide ensemble of computational hits, novel therapeutics to prevent and/or treat COVID- 19.

Immune checkpoints are vital molecules and pathways of the immune system with defined roles of controlling immune responses from being destructive to the healthy cells in the body. They include inhibitory receptors and ligands, which check the recognition of most cancers by the immune system. This happens when proteins on the surface of T cells called immune checkpoint proteins identify partner proteins on the cancer cells and bind to them, sending brake signals to the T cells to evade immune attack. However, drugs called immune checkpoint inhibitors block checkpoint proteins from binding to their partner proteins, thereby inhibiting the brake signals from being sent to T cells. This eventually allows the T cells to destroy cancer cells and arbitrate robust tumor regression. Many such inhibitors have already been approved and are in various developmental stages. The well-illustrated inhibitory checkpoints include the cytotoxic T lymphocyte-associated molecule-4 (CTLA-4), programmed cell death receptor-1 (PD-1), and programmed cell death ligand-1 (PD-L1). Though many molecules blocking these checkpoints have shown promise in treating many malignancies, such treatment options have limited success in terms of the immune response in most patients. Against this backdrop, exploring new pathways and next-generation inhibitors becomes imperative for developing more responsive and effective immune checkpoint therapy. Owing to the complex biology and unexplored ambiguities in the mechanistic aspects of immune checkpoint pathways, analysis of the activity profile of new drugs is the subject of strenuous investigation. We herein report the recent progress in developing new inhibitory pathways and potential therapeutics and delineate the developments based on their merit. Further, the ensuing challenges towards developing efficacious checkpoint therapies and the impending opportunities are also discussed.

Ovarian cancer (OC) is the 3rd common gynecologic cancer. Numerous procedures are involved in the growth of OC, like migration, angiogenesis, proliferation, apoptosis, invasion, and metastasis. Therefore, a better knowledge of the molecular processes complicated in ovarian tumorigenesis can lead to better measures for the prevention and treatment of the disease and its diagnosis. Long non-coding RNAs (LncRNAs), a subclass of non-coding RNAs, are much more diverse than previously thought. It is suggested that these RNAs may play a role in controlling complex cellular signaling mechanisms via binding to proteins and influencing their function. Nevertheless, our acquaintance with the participation of LncRNAs in the pathogenesis of OC is still restricted. Especially, we do not yet recognize how to pharmacologically correct the epi-mutations. Resveratrol, a natural polyphenol mostly derived from grapes, has been evaluated in many studies to find its cancer therapeutic potential. In the current paper, we aimed to review the role of resveratrol as a potential natural product on lncRNAs as novel diagnostic and therapeutic targets in OC and represent new insights for further investigations.

Objective: A simple pH and redox dual stimuli-responsive diketopyrrolopyrrole (DPP)-Cu²⁺ complexes gated mesoporous silica nanoparticles (MSN) were prepared for precise drug delivery and controlled drug release. Method: MSN was prepared by sol-gel method and then laminated. Carboxylic acid (CA)-Pyrrolo[3,4-c] pyrrole-1,4-dione, 2,5-dihydro-3,6-di-2-pyridinyl (PyDPP) was grafted onto the surface of amino-functionalized MSN (MSN-NH2) through a simple amide reaction and then complexed with Cu²⁺ to form gated molecules after doxorubicin (DOX) loading. Results: Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Low-angle X-ray diffraction (XRD) showed that MSN with uniform particle size (100 nm) and porous structure was successfully prepared. The prepared MSN, MSN- NH2, and MSN-DPP were fully characterized by Zeta potential, Fourier transforms infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption- desorption. High DOX-loading capacity (18.22%) and encapsulation efficiency (89.16%) were achieved by optimizing the mass ratio of MSN to DOX. Release studies showed that the gated molecules of our designed DPP-Cu²⁺ complexes had a good blocking effect under physiological conditions (the cumulative release rate of drugs within 24 hours was only 4.18%) and responded well to the pH and redox glutathione (GSH) dual stimuli. In vitro cytotoxicity assay showed that MSN-DPP-Cu²⁺ had good biocompatibility in both Hep G2 cells and L02 cells (the relative cell viability of both cells within 48 hours was above 97%), and the MSN-DPP-Cu²⁺@DOX could be triggered for efficient drug release in Hep G2 cells. Conclusion: The MSN-DPP-Cu²⁺ described in this research may be a good delivery system for the controlled release of antitumor drugs and can provide a potential possibility for clinical application in the future.

Background: Diabetic nephropathy (DN) is one of the most serious complications of diabetes mellitus and the main cause of the end-stage renal disease (ESRD). Activation of the NLRP3 inflammasome has been proven to play an important role in the development of DN. Thus, specific and direct targets of NLRP3 inflammasome assembly may have therapeutic potential. CY-09 is a new NLRP3 inflammasome specific inhibitor that has been shown to protect against non-alcoholic fatty liver disease (NAFLD) by inhibiting the activation of the NLRP3 inflammasome. However, its role in kidney disease, especially DN, has not been reported. Methods: In this study, we used HE staining to assess renal pathological damage in each group, and RT-PCR, immunofluorescence and WB were performed to detect the expression changes in inflammatory and fibrosis proteins. The apoptosis level was detected by TUNEL staining. Results: Here, we showed increased inflammation, oxidative stress, apoptosis and fibrosis in db/db mice, while CY-09 exerted renoprotection by inhibiting NLRP3 inflammasome activation. In vitro, CY-09 also inhibited NLRP3 and reduced caspase-1, IL-18, IL-1β and apoptosis in a dose-dependent manner. Conclusion: CY-09 effectively protects the kidney from hyperglycemia induced damage by inhibiting the NLRP3 inflammasome and may be a promising therapeutic strategy to prevent the progression of DKD.