Torin1

Environmental herbicides are increasingly recognized as contributors to male reproductive decline, yet the cellular mechanisms underlying their toxicity remain poorly defined. Here we show that Florasulam, a widely used triazolopyrimidine sulfonanilide herbicide, directly disrupts Leydig cell homeostasis and steroidogenic function. Florasulam reduces TM3 Leydig cell viability and promotes apoptosis, accompanied by decreased expression of the anti-apoptotic protein Bcl-2 and the steroidogenic enzyme HSD3B2. Transcriptomic profiling reveals early suppression of autophagy-related pathways together with enrichment of endoplasmic reticulum (ER) stress signatures. Consistent with these findings, Florasulam inhibits autophagic flux, marked by p62 accumulation, reduced LC3-II levels, and diminished autophagosome formation, and simultaneously activates the PERK-eIF2α-ATF4-CHOP signaling cascade indicative of unresolved ER stress. Pharmacological restoration of autophagy with Rapamycin or Torin1 attenuates ER stress and significantly reduces apoptosis. These results identify a critical autophagy-ER stress axis underlying Florasulam-induced Leydig cell injury and provide mechanistic insight into the reproductive risks associated with herbicide exposure.

Hutchinson-Gilford progeria syndrome (HGPS) is a rare progeroid disorder, and approximately 90% of cases are caused by LMNA mutation that yields the lamin A/C variant progerin. Progerin is toxic, and its clearance and disruption have positive benefits on HGPS cells and mice and even HGPS patients. However, accelerating progerin clearance is still an unaddressed issue. Here, we report that primary cells from HGPS patients displayed lysosome defects and that counteracting lysosome defects via the activation of lysosome biogenesis promoted progerin clearance and accordingly alleviated cellular senescence in HGPS. We revealed that nucleus-localized progerin was expelled into the cytoplasm via nuclear envelope (NE) budding and degraded through autophagy in HGPS cells. Lysosome defects occurred in HGPS cells and impaired progerin clearance. Activating lysosome biogenesis via the protein kinase C (PKC) activator phorbol 12-myristate 13-acetate (PMA) or the mTORC1 inhibitor Torin 1 promoted progerin clearance and accordingly mitigated DNA damage, cell cycle arrest, low proliferation ability and senescence-associated secretory phenotype (SASP) in HGPS cells. Overall, we propose that, in HGPS, lysosomes exhibit defects and that activating lysosome biogenesis can accelerate progerin clearance and alleviate cellular senescence. These findings highlight the anti-senescence roles of PKC activation and lysosome biogenesis and provide new insights for understanding and treating HGPS.