Andrographolide suppresses hypoxia-induced embryonic hyaloid vascular system development through HIF-1a/VEGFR2 signaling pathway

A preventative role of nitrate for hypoxia-induced intestinal injury

BACKGROUND

Studying effective interventions for hypoxia-induced injury is crucial, particularly in high-altitude areas. Symptoms stemming from intestinal injuries have a significant impact on the health of individuals transitioning from plains to plateau regions. This research explores the effects and mechanisms of nitrate supplementation in preventing hypoxia-induced intestinal injury.

METHODS

A hypoxia survival mouse model was established using 7% O2 conditions. The intervention with 4 mM sodium nitrate (NaNO3) in drinking water commenced 7 days prior to hypoxia exposure. Weight monitoring, hematoxylin and eosin (HE) staining, transmission electron microscopy (TEM), and intestinal permeability assays were employed for physiological, histological, and functional analyses. Quantitative PCR (qPCR), Western blot, and immunofluorescence were utilized to analyze the levels of tight junction (TJ) proteins and hypoxia-inducible factor 1α (Hif 1α). RNA sequencing (RNA-seq) identified nitrate's target, and chromatin immunoprecipitation (ChIP) verified the transcriptional impact of Hif 1α on TJ proteins. Villin-cre mice infected with AAV9-FLEX-EGFP-Hif 1α were used for mechanism validation.

RESULTS

The results demonstrated that nitrate supplementation significantly alleviated small intestinal epithelial cell necrosis, intestinal permeability, disruption of TJs, and weight loss under hypoxia. Moreover, the nitrate-triggered enhancement of TJs is mediated by Hif 1α nuclear translocation and its subsequent transcriptional function. The effect of nitrate supplementation on TJs was largely attributed to the stimulation of the EGFR/PI3K/AKT/mTOR/Hif 1α signaling pathways.

CONCLUSION

Nitrate serves as a novel approach in preventing hypoxia-induced intestinal injury, acting through Hif 1α activation to promote the transcription of TJ proteins. Furthermore, our study provides new and compelling evidence for the protective effects of nitrate in hypoxic conditions, especially at high altitudes.

Decoding the mechanism of andrographolide to combat hepatocellular carcinoma: a network pharmacology integrated molecular docking and dynamics approach

HepatoCellular Carcinoma, being one of the most mortally convoluted malignancy with mounting number of occurrences across the world and being classified as the third most prevalent cause of cancer-associated mortalities and sixth most prevalent neoplasia. The active phytoconstituent andrographolide, derived from Andrographis paniculata is conveyed to reconcile a number of human ailments including various oncologies. However, the molecular mechanism underlying the anti-oncogenic effects of Andrographolide on HCC remains skeptical and unclear, emerging as a budding challenge for researchers and oncologists. The present study intends to analyze the underlying pharmacological mechanism of Andrographolide over HCC, established via assimilated approach of network pharmacology. Herein, the Network pharmacology stratagem was instigated to investigate potential HCC targets. The Andrographolide targets along with HCC targets were extracted from multiple databases. A total of 162 potential overlapping targets among HCC and Andrographolide were obtained and further subjected to gene ontology and Pathway enrichment analysis by employing OmicsBox and DAVID database, respectively. Subsequently, Protein-protein interaction network construction by Cytoscape software identified the top 10 hub nodes which were validated by survival and expression analysis. Further, the results derived from molecular docking and dynamic simulations by CB-Dock2 server and Desmond module (Schrodinger software) indicate ALB, CCND1, HIF1A, TNF, and VEGFA as potential Andrographolide related targets with high binding affinity and promising complex stability. Our findings not only reveal the antioncogenic role of andrographolide but also provide novel insights illuminating the identified targets as scientific foundation for anti-oncogenic clinical application of andrographolide in HCC therapeutics.Communicated by Ramaswamy H. Sarma.