Seed-borne endophyte Epichloë gansuensis enhance NaCl tolerance in Achnatherum inebrians and increase its biomass. However, the molecular mechanism by which E. gansuensis increases the tolerance of host grasses to NaCl stress is unclear. Hence, we firstly explored the full-length transcriptome information of A. inebrians by PacBio RS II. In this work, we obtained 738,588 full-length non-chimeric reads, 36,105 transcript sequences and 27,202 complete CDSs from A. inebrians. We identified 3558 transcription factors (TFs), 15,945 simple sequence repeats and 963 long non-coding RNAs of A. inebrians. The present results show that 2464 and 1817 genes were differentially expressed by E. gansuensis in the leaves of E+ and E− plants at 0 mM and 200 mM NaCl concentrations, respectively. In addition, NaCl stress significantly regulated 4919 DEGs and 502 DEGs in the leaves of E+ and E− plants, respectively. Transcripts associated with photosynthesis, plant hormone signal transduction, amino acids metabolism, flavonoid biosynthetic process and WRKY TFs were differentially expressed by E. gansuensis; importantly, E. gansuensis up-regulated biology processes (brassinosteroid biosynthesis, oxidation–reduction, cellular calcium ion homeostasis, carotene biosynthesis, positive regulation of proteasomal ubiquitin-dependent protein catabolism and proanthocyanidin biosynthesis) of host grass under NaCl stress, which indicated an increase in the ability of host grasses’ adaptation to NaCl stress. In conclusion, our study demonstrates the molecular mechanism for E. gansuensis to increase the tolerance to salt stress in the host, which provides a theoretical basis for the molecular breed to create salt-tolerant forage with endophytes.

Cellular senescence is a pivotal driver of aging and age-related diseases. This study aims to systematically investigate the anti-senescence effects and molecular mechanisms of a multi-component botanical complex (SBT) using both a D-galactose-induced senescence model in H9c2 cardiomyocytes and an H2O2-induced accelerated aging model in zebrafish. The SBT complex comprises Solms-laubachia eurycarpa, Bergenia purpurascens, Laccifer lacca, and Glycyrrhiza uralensis. Results demonstrated that SBT treatment significantly enhanced cell viability (increased from 52% to 85%) and reduced senescence-associated β-galactosidase (SA-β-gal) activity (from 41.2% to 20%). At the molecular level, SBT exerted bidirectional regulation of the P21/P53/SIRT1 axis, coordinately downregulating the pro-senescence proteins P53 and P21 while upregulating the longevity-associated deacetylase SIRT1. It also modulated the balance of apoptosis-related genes by suppressing Bax and enhancing Bcl-2 expression. In the zebrafish model, SBT significantly strengthened the antioxidant defense system, as indicated by increased activities of superoxide dismutase (SOD) and catalase (CAT), elevated glutathione (GSH) levels, and reduced malondialdehyde (MDA) content. These findings confirm that SBT exerts potent anti-senescence effects through bidirectional regulation of the P21/P53/SIRT1 signaling axis, enhanced antioxidant capacity, and inhibition of apoptosis, thereby providing a mechanistic foundation for the development of natural product-based interventions against aging and related diseases.