Diterpenes/Diterpenoids and Their Derivatives as Potential Bioactive Leads against Dengue Virus: A Computational and Network Pharmacology Study.

Dengue fever is a dangerous infectious endemic disease that affects over 100 nations worldwide, from Africa to the Western Pacific, and is caused by the dengue virus, which is transmitted to humans by an insect bite of Aedes aegypti. Millions of citizens have died as a result of dengue fever and dengue hemorrhagic fever across the globe. Envelope (E), serine protease (NS3), RNA-directed RNA polymerase (NS5), and non-structural protein 1 (NS1) are mostly required for cell proliferation and survival. Some of the diterpenoids and their derivatives produced by nature possess anti-dengue viral properties. The goal of the computational study was to scrutinize the effectiveness of diterpenoids and their derivatives against dengue viral proteins through in silico study. Methods: molecular docking was performed to analyze the binding affinity of compounds against four viral proteins: the envelope (E) protein, the NS1 protein, the NS3 protein, and the NS5 protein. Results: among the selected drug candidates, triptolide, stevioside, alepterolic acid, sphaeropsidin A, methyl dodovisate A, andrographolide, caesalacetal, and pyrimethamine have demonstrated moderate to good binding affinities (-8.0 to -9.4 kcal/mol) toward the selected proteins: E protein, NS3, NS5, and NS1 whereas pyrimethamine exerts -7.5, -6.3, -7.8, and -6.6 kcal/mol with viral proteins, respectively. Interestingly, the binding affinities of these lead compounds were better than those of an FDA-approved anti-viral medication (pyrimethamine), which is underused in dengue fever. Conclusion: we can conclude that diterpenoids can be considered as a possible anti-dengue medication option. However, in vivo investigation is recommended to back up the conclusions of this study.

GC-MS analysis, and evaluation of protective effect of Piper chaba stem bark against paracetamol-induced liver damage in Sprague-Dawley rats: Possible defensive mechanism by targeting CYP2E1 enzyme through in silico study.

The present study attempted to scrutinize the protective effect of the methanolic extract of P. chaba stem bark against paracetamol-induced hepatotoxicity in Sprague-Dawley rats, along with the gas chromatography-mass spectrometry (GC-MS) analysis to identify phytochemicals, which were further docked in the catalytic site of CYP2E1 and the MD simulation for system that plays a major role in the bio-activation of toxic substances that produce reactive metabolites, leading to hepatotoxicity. P. chaba stem methanol extract (250 and 500 mg/kg) were treated orally with the negative control and the negative control silymarin (50 mg/kg) groups. Phytochemical profiling was conducted using GC-MS. In in-silico studies, PyRx software was used for docking analysis and the stability of the binding mode in the target active sites was evaluated through a set of standard MD-simulation protocols using the Charmm 27 force field and Swiss PARAM. Co-administration of P. chaba at both doses with APAP significantly reduced the APAP-augmented liver marker enzymes ALT, AST, ALP, and LDH, along with serum albumin, globulin, hepatic enzymes, histopathological architecture, lipid profiles, total protein, and total bilirubin, and elevated the levels of MDA. The GC-MS analysis indicated that P. chaba extract is enriched in fatty acid methyl esters (46.23 %) and alkaloids (10.91 %) and piperine is represented as a main phytochemical. Among all the identified phytochemicals, piperine (-8.0 kcal/mol) was found to be more interacting and stable with the binding site of CYP2E1. Therefore, all of our findings may conclude that the P. chaba stem extract and its main compound, piperine, are able to neutralize APAP-induced hepatic damage.

Effects of nerol on paracetamol-induced liver damage in Wistar albino rats.

Nerol, a monoterpene is evident to possess diverse biological activities, including antioxidant, anti-microbial, anti-spasmodic, anthelmintic, and anti-arrhythmias. This study aims to evaluate its hepatoprotective effect against paracetamol-induced liver toxicity in a rat model. Five groups of rats (n = 7) were orally treated (once daily) with 0.05% tween 80 dissolved in 0.9% NaCl solution (vehicle), paracetamol 640 mg/kg (negative control), 50 mg/kg silymarin (positive control), or nerol (50 and 100 mg/kg) for 14 days, followed by the hepatotoxicity induction using paracetamol (PCM). The blood samples and livers of the animals were collected and subjected to biochemical and microscopical analysis. The histological findings suggest that paracetamol caused lymphocyte infiltration and marked necrosis, whereas maintenance of the normal hepatic structural was observed in group pre-treated with silymarin and nerol. The rats pre-treated with nerol significantly and dose-dependently reduced the hepatotoxic markers in animals. Nerol at 100 mg/kg significantly reversed the paracetamol-induced altered situations, including the liver enzymes, plasma proteins, antioxidant enzymes and serum bilirubin, lipid peroxidation (LPO) and cholesterol [e.g., total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c)] levels in animals. Taken together, nerol exerted significant hepatoprotective activity in rats in a dose-dependent manner. PCM-induced toxicity and nerol induced hepatoprotective effects based on expression of inflammatory and apoptosis factors will be future line of work for establishing the precise mechanism of action of nerol in Wistar albino rats.