Procyanidin C1: A Natural Dual‑Mode Senotherapeutic for Pan‑Organ Senescence Modulation and Clearance

Cellular senescence is driven by DNA damage, telomere attrition, and metabolic/mitochondrial stress, culminating in a state of durable proliferative arrest accompanied by a senescence-associated secretory phenotype (SASP) that amplifies inflammation and paracrine remodeling across tissues, thereby accelerating functional decline and age-related pathologies. This review examines the molecular mechanisms and in vivo activities of procyanidin C1 (PCC1), a natural dualmode senotherapeutic. Its dual behavior is characterized by an early or lowdose phase in which PCC1 attenuates selected NFκB–driven SASP components while stabilizing redox and bioenergetic homeostasis; under high senescent burden or tumor-associated stress, elevated doses of PCC1 enable the selective reduction of refractory senescent cells and mitigation of pro-tumorigenic SASP outputs, concomitant with modulation of immune infiltration and metabolic reprogramming. PCC1 further exhibits pronounced anti-inflammatory and anti-tumor potential by reshaping inflammatory and chemotactic gradients within the tumor microenvironment. Reflecting broad multi-organ geroprotective activity, PCC1 can exert antioxidative, mitochondrial-supportive, and anti-fibrotic modulation in cardiovascular/metabolic tissues, skin, liver, kidney, and neural niches. Compared with BCL-2 inhibitors or multi-kinase senolytics, PCC1 shows lower cytotoxicity toward normal proliferating cells and fewer indications of platelet or hematopoietic suppression, with its staged regulatory profile and natural scaffold suggesting a wider therapeutic window. Future priorities include quantifying dose–timing transition thresholds, establishing integrated biomarker panels, and optimizing delivery strategies to define its translational potential in precision, phase-adapted senescence and tumor microenvironment interventions.