Silicon-Based Antioxidant Agent Reduces Frailty Markers in Aging Mouse Models

Frailty—the age-related loss of physiological resilience—raises mortality risk and reduces quality of life in older adults worldwide. Its onset is strongly linked to elevated oxidative stress and declining antioxidant capacity, making antioxidant intervention an appealing therapeutic avenue. However, most antioxidant compounds face limitations in bioavailability or selectivity. This study evaluated a silicon (Si)-based agent that reacts with water in the gut to continuously generate molecular hydrogen, which selectively neutralizes the most damaging reactive oxygen species without disrupting beneficial redox signaling.

The study used two complementary mouse models. Klotho knockout mice (lacking the aging-suppressor klotho gene) develop rapid, systemic frailty-like deterioration by 2–2.5 months—making them a reproducible model for frailty-associated functional decline under oxidative stress. Naturally aged 105-week-old C57BL/6J mice served as a physiological aging comparator. Klotho mice were fed standard diet (control), diet with 1% Si-agent (S1), or 2.5% Si-agent (S2) from 4–7 weeks of age. Assessments included macroscopic physical scoring, body measurements, spontaneous cage activity, open-field locomotion testing, and rotarod motor coordination testing. A formal Fried-criteria-adapted frailty classification was applied using five parameters: spontaneous activity, travel distance, locomotor speed, rotarod latency, and body weight.

In klotho mice, Si treatment produced striking improvements. Only 30–40% of Si-treated mice showed aging features (kyphosis, sparse coat, organ atrophy, undescended testes) versus the majority of untreated controls. Body and total lengths were significantly greater in both Si groups. Spontaneous activity, open-field travel distance, speed, and active time were all significantly preserved in S1 and S2 groups. Rotarod latency was significantly improved in the S2 group. Critically, frailty classification revealed 57% of untreated klotho mice were frail and 29% pre-frail, while zero mice in either Si group were classified as frail, with only 14% (S1) and 7% (S2) pre-frail. In aged C57BL/6J mice, Si treatment measurably reduced systemic oxidative stress biomarkers, attenuated age-related body weight loss and motor performance decline, and reduced early mortality.

These findings position the Si-based agent as a compelling, orally deliverable anti-frailty intervention. Its mechanism—sustained endogenous hydrogen production selectively scavenging hydroxyl radicals and peroxynitrite—offers advantages over conventional antioxidants. Prior work already demonstrated efficacy in Parkinson's disease, ulcerative colitis, facial nerve palsy, and ischemia-reperfusion models, and recent success in age-related vertigo strengthened the case for aging applications. The current study extends this profile directly into frailty.

Important caveats exist. Klotho mice are a genetic model of accelerated aging rather than true physiological aging, and results may not fully translate to natural human aging trajectories. The C57BL/6J aged mouse data, while supportive, are presented more briefly. Optimal dosing, long-term safety, and efficacy across sexes require further study, and human clinical trials are needed before any clinical recommendations can be made.