Investigating Chaperone like Activity of Green Silver Nanoparticles: Possible Implications in Drug Development

Inhibition of protein misfolding and aggregation by steroidal quinoxalin-2(1H)-one and their molecular docking studies

A series of D-ring fused 16-substituted steroidal quinoxalin-2(1H)-one attached to an electron-releasing (ER) or electron-withdrawing (EW) groups via steroidal oxoacetate intermediate were synthesized to investigate their protein aggregation inhibition potential using human lysozyme (HLZ). The influence of the type of substituent at the C-6 positions of the quinoxalin-2(1H)-one ring on the protein aggregation inhibition potential was observed, showing that the EW moiety improved the protein aggregation inhibition potency. Of all the evaluated compounds, NO2-substituted quinoxalin-2(1H)-one derivative 13 was the most active compound and had a maximum protein aggregation inhibition effect. Significant stabilization effects strongly support the binding of the most biologically active steroidal quinoxalin-2(1H)-one with docking studies. The predicted physicochemical and ADME properties lie within a drug-like space which shows no violation of Lipinski's rule of five except compounds 12 and 13. Combined, our results suggest that D-ring fused 16-substituted steroidal quinoxalin-2(1H)-one has the potential to modulate the protein aggregation inhibition effect.

One-pot microwave synthesis of chitosan-stabilized silver nanoparticles entrapped polyethylene oxide nanofibers, with their intrinsic antibacterial and antioxidant potency for wound healing

Different physical and chemical techniques could be used to prepare chitosan/Silver nanoparticle (CHS/AgNPs) nanocomposite. The microwave heating reactor was rationally adopted as a benign tool for preparing CHS/AgNPs owing to less energy consumption and shorter time required for completing the nucleation and growth particles. UV-Vis, FTIR, and XRD, provided conclusive evidence of the AgNPs creation, while TEM micrographs elucidated that the size was spherical (20 nm). CHS/AgNPs were embedded in polyethylene oxide (PEO) nanofiber via electrospinning, and their biological properties, cytotoxicity evaluation, antioxidant, and antibacterial activity assays were investigated. The generated nanofibers have mean diameters of 130.9 ± 9.5, 168.7 ± 18.8, and 186.8 ± 8.19 nm for PEO, PEO/ CHS, and PEO/ CHS (AgNPs), respectively. Because of the tiny AgNPs particle size loaded in PEO/CHS (AgNPs) fabricated nanofiber, good antibacterial activity with ZOI against E. coli was 51.2 ± 3.2, and S. aureus was 47.2 ± 2.1 for PEO/ CHS (AgNPs) nanofibers. Non-toxicity was observed against Human Skin Fibroblast and Keratinocytes cell lines (>93.5 %), which justifies its great antibacterial potential to remove or prevent infection in wounds with fewer adverse effects.

Microwave-assisted one-pot multicomponent synthesis of steroidal pyrido[2,3-d]pyrimidines and their possible implications in drug development

Protein misfolding can lead to fibrillar and non-fibrillar deposits which are the signs of countless human diseases. A promising strategy for the prevention of such diseases is the inhibition of protein aggregation, and the most crucial step toward effective prevention is the development of small molecules having the potential for protein-aggregation inhibition. In this search, a series of novel steroidal pyrido[2,3-d]pyrimidines have been synthesized employing steroidal ketone, substituted aldehydes, and 2,6-diaminopyrimidin-4(3H)-one through the microwave-assisted one-pot multicomponent methodology. The aggregation inhibition potential of newly synthesized compounds was evaluated on human lysozyme (HLZ). All the synthesized compounds were found to be efficient in the inhibition of protein aggregation in carefully designed in vitro experiments. Moreover, molecular docking studies also determine the binding interactions between all the synthesized compounds and native HLZ through hydrogen bonding. The structures of synthesized compounds were also elucidated using various spectroscopic techniques.

Nano drug (AgNPs capped with hydroxychloroquine): Synthesis, characterization, anti-covid-19 and healing the wound infected with S. aureus

Almost existing anti-viral drugs are only organic molecules that are able to circumvent the system the virus works with, which leaves it facing the immune system of our bodies and then kills it. Unfortunately, this type of pharmacological fight did not succeed in a way to overcome this virus, so it became necessary to think outside the box, to find a drug that would kill the virus or alter its protein structure. This research aims to prepare silver nanoparticle (AgNPs) by the green method depending on the reaction of the silver nitrate (safe for humans) with the phoenix dactylifera extract (safe for humans) and then coated with the hydroxychloroquine (HQ, known antiviral drug). This substance will fight the virus with different mechanisms (i) silver will carry the drug to cells easily, and then (ii) nano silver will perform a physical inhibition of the virus and thus reduce its susceptibility to binding to host cells. In addition, (iii) silver nanoparticle is much smaller than the size of the virus which qualifies it to cross into the virus and change the structure of RNA. Furthermore, (iv) it is possible for silver to interact with the amino and carboxylic ends in the virus proteins. The results of TCID50 shows that the prepared nano drug is able to reduce the viability of covid-19 to about 22% using 400 mg/ml of AgNPs/HQ. The resulted nanodrug was also used for healing the wound infected with S. aureus and the histological results revealed that all of the disease symptoms improved, with the epidermal layer multiplying quickly and the infected wounds healing quickly.