Alternative splicing generates a novel ferroportin isoform with a shorter C-terminal and an intact iron- and hepcidin-binding property.

Ferroportin (FPN) is a transmembrane protein and is the only known iron exporter that helps in maintaining iron homeostasis in vertebrates. To maintain stable iron equilibrium in the body, ferroportin works in conjunction with a peptide called hepcidin. In this study, we have identified an alternatively spliced novel isoform of the human SLC40A1 gene, which encodes for the FPN protein and is found to be expressed in different tissues. The novel transcript has an alternate last exon and encodes 31-amino acid long peptide sequence that replaces 104 amino acids at C-terminal in the novel transcript. Molecular modelling and molecular dynamics (MD) simulation studies revealed key structural features of the novel isoform (FPN-N). FPN-N was predicted to have 12 transmembrane domains similar to the reported isoform (FPN), despite being much smaller in size. FPN-N was found to interact with hepcidin, a key regulator of ferroportin activity. Also, the iron-binding sites were retained in the novel isoform as revealed by the MD simulation of FPN-N in bilipid membrane. The novel isoform identified in this study may play important role in iron homeostasis. However, further studies are required to characterize the FPN-N isoform and decipher its role inside the cell.

Analysis and prediction pathways of natural products and their cytotoxicity against HeLa cell line protein using docking, molecular dynamics and ADMET.

Natural product such as flavonoids and their derivatives have a discernible capability to inhibit tumor formation and the growth of cancer cell, which have a vital link between diet and chronic disease prevention. Several plants and spices that contain flavonoid derivatives have been used in traditional medicine as disease preventative and therapeutic agents. Therefore, flavonoids could be used as chemotherapeutic drugs, indicating their potential clinical utility in cancer treatment. The purpose of this research was to discover and produce innovative pharmaceuticals from natural sources by introducing structural changes into flavonoids' backbones and changing their structures to improve biological activity and anticancer effects. In the current study, it was expected that the percent unbound values for the 15 compounds in human plasma would be low, ranging between 0.188 and 0.391. However, all compounds have a safe range and are not toxic to the brain. Compounds 2, 10, and 13 were shown to be permeable to the CNS (log PS > -3), but all other compounds had difficulty penetrating the CNS. Furthermore, all compounds had a low total clearance, ranging from 0.038 to 1.216 ml/min/kg, indicating that these compounds have a long half-life. None of the compounds caused skin sensitization (SS), and only compounds 1, 11, and 12 are expected to be AMES-positive, suggesting that the other compounds are not mutagenic. The result of the study showed based on the Drug-likeness and ADMET studies, only 3 compounds, including 3, 4, and 15, have a good pharmacokinetics propriety, the lowest toxicity, and good binding affinity towards Caspase 3 V266APDB (ID: 5I9B) as potential inhibitor candidates for the HeLa cell line, they have a low total clearance property and no AMES mutagenicity or hERG inhibition properties. These compounds (3,4,15) were examined to act as new cytotoxic drug candidates and would have an interest as starting point for designing compounds against the HeLa cell line.Communicated by Ramaswamy H. Sarma.

Computational studies on phylogeny and drug designing using molecular simulations for COVID-19.

Since the first appearance of a novel coronavirus pneumonia (NCP) caused by a novel human coronavirus, and especially after the infection started its rapid spread over the world causing the COVID-19 (coronavirus disease 2019) pandemics, a very substantial part of the scientific community is engaged in the intensive research dedicated to finding of the potential therapeutics to cure this disease. As repurposing of existing drugs represents the only instant solution for those infected with the virus, we have been working on utilization of the structure-based virtual screening method to find some potential medications. In this study, we screened a library of 646 FDA approved drugs against the receptor-binding domain of the SARS-CoV-2 spike (S) protein and the main protease of this virus. Scoring functions revealed that some of the anticancer drugs (such as Pazopanib, Irinotecan, and Imatinib), antipsychotic drug (Risperidone), and antiviral drug (Raltegravir) have a potential to interact with both targets with high efficiency. Further we performed molecular dynamics simulations to understand the evolution in protein upon interaction with drug. Also, we have performed a phylogenetic analysis of 43 different coronavirus strains infecting 12 different mammalian species.Communicated by Ramaswamy H. Sarma.

Antioxidant properties and anti-mutagenic potential of Piper Cubeba fruit extract and molecular docking of certain bioactive compounds.

Spices and herbs are recognized as sources of natural antioxidants and thus play an important role in the chemoprevention of diseases and aging. Piper cubeba is one among them and known for its medicinal properties for decades. Various biological activities are associated with its extract and phytocompounds. However, the anti-mutagenic activity of antioxidant rich extract is less explored. In this study, we performed the fraction-based antioxidant activity of P. cubeba using four different assays and evaluated the anti-mutagenic activity of most potent antioxidant fraction using Salmonella typhimurium tester strains against four mutagens (methyl methanesulfonate [MMS], sodium azide [SA], benzo(a)pyrene, and 2-aminoflourene) respectively. Among all tested fractions at 25-200 µg/ml, ethanolic extract revealed highest antioxidant activity and significant anti-mutagenicity against both direct and indirect acting mutagens at least one tester strain. Phytochemical analysis by gas chromatography-mass spectrometry (GC/MS) revealed the presence of various phytocompounds including copaene, isocaryophyllene, α-cubebene, etc. Molecular docking studies on DNA binding interactions of GC/MS detected phytocompounds highlight the possible mode of binding. In summary, these in vitro studies have provided the scientific basis for validation of using this plant in the traditional system of medicine and highlighted the need for exploring the role of various compounds for therapeutic efficacy. On the other hand, synergistic interaction among phytocompounds is to be explored to optimize or standardize the extracts for the exploitation in modern phytomedicine.