Anti-infective properties of mung bean (Vigna radiata (L.)R. Wilczek) coat extract on Pseudomonas aeruginosa-infected Caenorhabditis elegans: Transcriptomics and pathway analysis

Abstract

Ethnopharmacological relevanceMung bean coat has long been known for its wide-ranging health benefits, including antibacterial, anti-inflammatory, and immune-modulatory properties. For many years in China, mung beans have been employed in the therapeutic management of inflammation induced by pathogenic bacteria infection, yet the precise underlying protective mechanisms remain to be comprehensively elucidated. Aim of the studyGiven the growing concern over antibiotic resistance, there is a necessity to explore new anti-infective agents. Here, the anti-infective properties of Mung bean coat extract (MBCE) were investigated using a model of Pseudomonas aeruginosa-infected nematodes. Materials and methodsThe protective effects of MBCE on Pseudomonas aeruginosa (PA14) infected nematodes were assessed by lifespan assay, reactive oxygen species (ROS) levels, transcriptomics, and Quantitative real-time PCR (qRT-PCR). ResultsMBCE significantly improved the survival rates and reduced ROS levels in infected worms. Transcriptomic profiling disclosed predominant KEGG pathway enrichments in immune responses, energy metabolism processes such as oxidative phosphorylation and the tricarboxylic acid cycle, alongside aging-related neurodegenerative diseases and longevity regulatory pathways like PI3K-AKT, MAPK, mTOR, and FOXO. qRT-PCR validation showed that MBCE upregulated antimicrobial peptides (spp-3, lys-1, lys-7, abf-2, cnc-2, nlp-33, clec-85), gram-negative responses (irg-3, src-2, grd-3, col-179), and mitochondrial function (mev-1) gene expressions, while downregulated insulin signaling-related (age-1, akt-1, akt-2, daf-15) gene expressions. Mutant strains lifespan analysis indicated that the nsy-1, sek-1, pmk-1, daf-2, aak-2, sir-2.1, and skn-1 were necessary for lifespan extension mediated by MBCE under PA14 infection, but not clk-1, isp-1, mev-1, or daf-16. ConclusionCollectively, our findings suggested that MBCE increased the survival rates of PA14-infected worms by activating downstream antimicrobial and antioxidant gene expressions through modulation of MAPK, daf-2, aak-2, sir-2.1, and skn-1 pathways. The research underscored the potential of natural plant compounds to strengthen the body's defenses against infections, potentially mitigating harmful ROS levels and improving survival. Additionally, these findings elucidated the mechanisms by which these plant-derived compounds enhance the immune system, implying their potential utility as dietary supplements or as an alternative to conventional antibiotics.