Parkinson’s disease (PD) and Alzheimer’s disease (AD) are neurodegenerative disorders that have emerged as among the serious health problems of the 21st century. The medications currently available to treat AD and PD have limited efficacy and are associated with side effects. Natural products are one of the most vital and conservative sources of medicines for treating neurological problems. Karanjin is a furanoflavonoid, isolated mainly from Pongamia pinnata with several medicinal plants, and has been reported for numerous health benefits. However, the effect of karanjin on AD and PD has not yet been systematically investigated. To evaluate the neuroprotective effect of karanjin, extensive in silico studies starting with molecular docking against five putative targets for AD and four targets for PD were conducted. The findings were compared with three standard drugs using Auto Dock 4.1 and Molegro Virtual Docker software. Additionally, the physiochemical properties (Lipinski rule of five), drug-likeness and parameters including absorption, distribution, metabolism, elimination and toxicity (ADMET) profiles of karanjin were also studied. The molecular dynamics (MD) simulations were performed with two selective karanjin docking complexes to analyze the dynamic behaviors and binding free energy at 100 ns time scale. In addition, frontier molecular orbitals (FMOs) and density-functional theory (DFT) were also investigated from computational quantum mechanism perspectives using the Avogadro-ORCA 1.2.0 platform. Karanjin complies with all five of Lipinski’s drug-likeness rules with suitable ADMET profiles for therapeutic use. The docking scores (kcal/mol) showed comparatively higher potency against AD and PD associated targets than currently used standard drugs. Overall, the potential binding affinity from molecular docking, static thermodynamics feature from MD-simulation and other multiparametric drug-ability profiles suggest that karanjin could be considered as a suitable therapeutic lead for AD and PD treatment. Furthermore, the present results were strongly correlated with the earlier study on karanjin in an Alzheimer’s animal model. However, necessary in vivo studies, clinical trials, bioavailability, permeability and safe dose administration, etc. must be required to use karanjin as a potential drug against AD and PD treatment, where the in silico results are more helpful to accelerate the drug development.

Anthraquinones (AQs) are found in a variety of consumer products, including foods, nutritional supplements, drugs, and traditional medicines, and have a wide range of pharmacological actions. Rubiadin, a 1,3-dihydroxy-2-methyl anthraquinone, primarily originates from Rubia cordifolia Linn (Rubiaceae). It was first discovered in 1981 and has been reported for many biological activities. However, no review has been reported so far to create awareness about this molecule and its role in future drug discovery. Therefore, the present review aimed to provide comprehensive evidence of Rubiadin’s phytochemistry, biosynthesis, physicochemical properties, biological properties and therapeutic potential. Relevant literature was gathered from numerous scientific databases including PubMed, ScienceDirect, Scopus and Google Scholar between 1981 and up-to-date. The distribution of Rubiadin in numerous medicinal plants, as well as its method of isolation, synthesis, characterisation, physiochemical properties and possible biosynthesis pathways, was extensively covered in this review. Following a rigorous screening and tabulating, a thorough description of Rubiadin’s biological properties was gathered, which were based on scientific evidences. Rubiadin fits all five of Lipinski’s rule for drug-likeness properties. Then, the in depth physiochemical characteristics of Rubiadin were investigated. The simple technique for Rubiadin’s isolation from R. cordifolia and the procedure of synthesis was described. Rubiadin is also biosynthesized via the polyketide and chorismate/o-succinylbenzoic acid pathways. Rubiadin is a powerful molecule with anticancer, antiosteoporotic, hepatoprotective, neuroprotective, anti-inflammatory, antidiabetic, antioxidant, antibacterial, antimalarial, antifungal, and antiviral properties. The mechanism of action for the majority of the pharmacological actions reported, however, is unknown. In addition to this review, an in silico molecular docking study was performed against proteins with PDB IDs: 3AOX, 6OLX, 6OSP, and 6SDC to support the anticancer properties of Rubiadin. The toxicity profile, pharmacokinetics and possible structural modifications were also described. Rubiadin was also proven to have the highest binding affinity to the targeted proteins in an in silico study; thus, we believe it may be a potential anticancer molecule. In order to present Rubiadin as a novel candidate for future therapeutic development, advanced studies on preclinical, clinical trials, bioavailability, permeability and administration of safe doses are necessary.

Viniferin is a resveratrol derivative. Resveratrol is the most prominent stilbenoid synthesized by plants as a defense mechanism in response to microbial attack, toxins, infections or UV radiation. Different forms of viniferin exist, including alpha-viniferin (α-viniferin), beta-viniferin (β-viniferin), delta-viniferin (δ-viniferin), epsilon-viniferin (ε-viniferin), gamma-viniferin (γ-viniferin), R-viniferin (vitisin A), and R2-viniferin (vitisin B). All of these forms exhibit a range of important biological activities and, therefore, have several possible applications in clinical research and future drug development. In this review, we present a comprehensive literature search on the chemistry and biosynthesis of and the diverse studies conducted on viniferin, especially with regards to its anti-inflammatory, antipsoriasis, antidiabetic, antiplasmodic, anticancer, anti-angiogenic, antioxidant, anti-melanogenic, neurodegenerative effects, antiviral, antimicrobial, antifungal, antidiarrhea, anti-obesity and anthelminthic activities. In addition to highlighting its important chemical and biological activities, coherent and environmentally acceptable methods for establishing vinferin on a large scale are highlighted to allow the development of further research that can help to exploit its properties and develop new phyto-pharmaceuticals. Overall, viniferin and its derivatives have the potential to be the most effective nutritional supplement and supplementary medication, especially as a therapeutic approach. More researchers will be aware of viniferin as a pharmaceutical drug as a consequence of this review, and they will be encouraged to investigate viniferin and its derivatives as pharmaceutical drugs to prevent future health catastrophes caused by a variety of serious illnesses.

Sarsasapogenin is a natural steroidal sapogenin molecule obtained mainly from Anemarrhena asphodeloides Bunge. Among the various phytosteroids present, sarsasapogenin has emerged as a promising molecule due to the fact of its diverse pharmacological activities. In this review, the chemistry, biosynthesis and pharmacological potentials of sarsasapogenin are summarised. Between 1996 and the present, the relevant literature regarding sarsasapogenin was obtained from scientific databases including PubMed, ScienceDirect, Scopus, and Google Scholar. Overall, sarsasapogenin is a potent molecule with anti-inflammatory, anticancer, antidiabetic, anti-osteoclastogenic and neuroprotective activities. It is also a potential molecule in the treatment for precocious puberty. This review also discusses the metabolism, pharmacokinetics and possible structural modifications as well as obstacles and opportunities for sarsasapogenin to become a drug molecule in the near future. More comprehensive preclinical studies, clinical trials, drug delivery, formulations of effective doses in pharmacokinetics studies, evaluation of adverse effects and potential synergistic effects with other drugs need to be thoroughly investigated to make sarsasapogenin a potential molecule for future drug development.

Bisphenol A (BPA), a well-known xenoestrogen, is commonly utilised in the production of polycarbonate plastics. Based on the existing evidence, BPA is known to induce neurotoxicity and behavioural issues. Flavonoids such as silibinin and naringenin have been shown to have biological activity against a variety of illnesses. The current research evaluates the neuropharmacological effects of silibinin and naringenin in a zebrafish model against neurotoxicity and oxidative stress caused by Bisphenol A. In this study, a novel tank diving test (NTDT) and light–dark preference test (LDPT) were used in neurobehavioural investigations. The experimental protocol was planned to last 21 days. The neuroprotective effects of silibinin (10 μM) and naringenin (10 μM) in zebrafish (Danio rerio) induced by BPA (17.52 μM) were investigated. In the brine shrimp lethality assay, the 50% fatal concentrations (LC₅₀) were 34.10 μg/mL (silibinin) and 91.33 μg/mL (naringenin) compared to the standard potassium dichromate (13.15 μg/mL). The acute toxicity investigation found no mortality or visible abnormalities in the silibinin- and naringenin-treated groups (LC₅₀ > 100 mg/L). The altered scototaxis behaviour in LDPT caused by BPA was reversed by co-supplementation with silibinin and naringenin, as shown by decreases in the number of transitions to the light zone and the duration spent in the light zone. Our findings point to BPA’s neurotoxic potential in causing altered scototaxis and bottom-dwelling behaviour in zebrafish, as well as the usage of silibinin and naringenin as potential neuroprotectants.

Genistein is a naturally occurring polyphenolic molecule in the isoflavones group which is well known for its neuroprotection. In this review, we summarize the efficacy of genistein in attenuating the effects of memory impairment (MI) in animals. Scopus, PubMed, and Web of Science databases were used to find the relevant articles and discuss the effects of genistein in the brain, including its pharmacokinetics, bioavailability, behavioral effects, and some of the potential mechanisms of action on memory in several animal models. The results of the preclinical studies highly suggested that genistein is highly effective in enhancing the cognitive performance of the MI animal models, specifically in the memory domain, including spatial, recognition, retention, and reference memories, through its ability to reduce oxidative stress and attenuate neuroinflammation. This review also highlighted challenges and opportunities to improve the drug delivery of genistein for treating MI. Along with that, the possible structural modifications and derivatives of genistein to improve its physicochemical and drug-likeness properties are also discussed. The outcomes of the review proved that genistein can enhance the cognitive performance and ameliorate MI in different preclinical studies, thus indicating its potential as a natural lead for the design and development of a novel neuroprotective drug.