Polyalthia longifolia leaves methanolic extract targets entry and budding of viruses-an in vitro experimental study against paramyxoviruses.

ETHNOPHARMACOLOGICAL RELEVANCE: Synthetic antiviral drugs have several limitations including high cost. Thus research on antiviral property of medicinal plants is continuously gaining importance. Polyalthia longifolia possesses several medicinal properties and has been used in traditional ayurvedic medicine for treatment of dermatological ailments as kushta, visarpa/herpes virus infection and also to treat pyrexia of unknown origin as mentioned in Visarpa Chikitsa. AIM OF THE STUDY: Keeping in view the cytotoxic, anti-cancer activity and antiviral efficacy of Polyalthia longifolia against herpes, present study was undertaken to evaluate the in vitro antiviral activity of methanolic extract of Polyalthia longifolia leaves, if any, and to unravel the possible target(s)/mechanism of action. MATERIAL AND METHODS: Antiviral activity of Polyalthia longifolia methanolic extract was studied using Vero cell lines against paramyxoviruses, namely-peste des petits ruminants virus (PPRV) and Newcastle disease virus (NDV). Cytotoxicity of the test extract was evaluated employing MTT assay. Virucidal activity, and viral-attachment, virus entry and release assays were determined in Vero cells using standard experimental protocols. The viral RNA in the virus-infected cells was quantified by qRT-PCR. RESULTS: At non-cytotoxic concentration, methanolic extract of Polyalthia longifolia leaves was found to inhibit the replication of PPRV and NDV at viral entry and budding level, whereas other steps of viral life cycle such as attachment and RNA synthesis remained unaffected. CONCLUSIONS: Polyalthia longifolia leaves extract possesses promising antiviral activity against paramyxoviruses and acts by inhibiting the entry and budding of viruses; and this plant extract evidently possesses excellent and promising potential for development of effective herbal antiviral drug.

Sex difference in mouse hypothalamic transcriptome profile in stress-induced depression model.

The influence of sex on prevalence and presentation of human depression necessitates studying its role in depression. Additionally, stress can also affect the incidence and progression of depressive phenotypes. Hypothalamus is a well-reported sexually dimorphic brain region. Hence, we performed a gene-array to uncover the chronic stress-induced transcriptional changes in the hypothalamus of male, intact female (with ovaries) and ovariectomized female mice. Chronic variable mild stress model was used to induce depression-like behavior in mice, assessed by despair behavior in forced swim test. We observed 90, 205 and 106 uniquely expressed genes among the 114, 226 and 121 stress-regulated genes (fold change >1.2 and p < 0.05) in male, intact female, and ovariectomized female group mice respectively. Pathway analysis of the altered genes identified 'posttranslational processing of neuroendocrine peptides' as the most significantly enriched pathway and also differentially regulated among the groups. Arginine vasopressin and Cholecystokinin were upregulated in males whereas in ovariectomized females Arginine vasopressin alone was upregulated, and Oxytocin was downregulated in intact females. A greater number of nodes and connections found in intact females indicate their intricate molecular response to chronic stress condition. These results suggest that stress-regulated transcriptional changes in the hypothalamus are sex-specific and ovarian hormone-dependent, which warrants urgent sex-based medical attention in depressive disorder.