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von Zglinicki, T.

Publications and source records attributed to von Zglinicki, T..

5 recordsLinked to original sources

Repurposing Regulatory Toxicology Safety Data to Identify Potential Pro-Longevity Substances

The repurposing of existing biosafety datasets offers unique opportunities in biomedical research. Here, we demonstrate how pesticide toxicity data, which include long-term survival studies in mammalian models, can be harnessed to uncover potential drug candidates or drug targets that can improve survival. We show that these substances frequently affect mitochondrial bioenergetics and that they can improve animal healthspan.

cell biology↗

Comparable anti-ageing efficacies of a multi-ingredient nutraceutical and a senolytic intervention in old mice

Single-ingredient dietary supplements have demonstrated some potential to extend lifespan and improve healthspan; however, the efficacy of defined multi-ingredient nutraceuticals remains underexplored. Senolytic interventions have been successful in reducing multi-morbidity, frailty, and cognitive decline in animal models and are seen as promising anti-ageing interventions in mammals. We compared the effects of a 12-ingredient nutraceutical on mice lifespan and healthspan markers with that of a high efficacy senolytic intervention consisting of a low dose of Navitoclax combined with the specific mitochondrial uncoupler BAM15. Both interventions were started at old age (20 months). The supplement was given daily until the end of the experiment (30 months of age), but the senolytic intervention consisted of two short (5 days each) rounds of treatment at 20 and 23 months of age. Despite late onset, both interventions increased median lifespan similarly by around 20% over controls. The senolytic intervention significantly reduced frailty progression and improved cognitive function after the second round of treatment, but without subsequent treatment, these effects appeared to wane at later ages. The multi-ingredient supplement tended to reduce frailty progression steadily with time, albeit not significant, and maintained cognitive function. Mechanistically, in vitro, there was no evidence of senolytic activity of the multi-ingredient nutraceutical as a whole nor of its individual ingredients. Continuous multi-ingredient dietary supplementation shows promise in achieving comparable anti-ageing efficacy as a senolytic intervention.

cell biology↗

Mild uncoupling of mitochondria synergistically enhances senolytic specificity and sensitivity of BH3 mimetics

Anti-senescence interventions are exceptionally effective in alleviating a wide range of age-associated diseases and disabilities. However, the sensitivity and specificity of current senolytic interventions are limited. Mitochondrial dysfunction is an integral part of the senescent phenotype and we demonstrate that specific loss of complex I-linked coupled respiration and the inability to maintain mitochondrial membrane potential upon respiratory stimulation are early and persistent features in a cells progression towards senescence. We thus identify senescence-associated mitochondrial dysfunction as a targetable vulnerability of senescent cells and show that further decreasing mitochondrial membrane potential of senescent cells with a low concentration of a mitochondrial uncoupler synergistically enhances the in vitro senolytic efficacy of BH3 mimetic drugs, including Navitoclax, by up two orders of magnitude. Moreover, in an in vivo mouse model of radiation-induced premature ageing, we show that a short-term intervention combining the mitochondrial uncoupler BAM15 with Navitoclax at a dose two orders of magnitude lower than typically used reduces frailty and improves cognitive function for at least 8 months after irradiation. Therefore our study shows that compromised mitochondrial functional capacity is a specific vulnerability of senescent cells which can be targeted by mild uncoupling in vitro and in vivo.

cell biology↗

NLRP1 inflammasome modulates senescence and senescence-associated secretory phenotype

Senescence is a cellular aging-related process triggered by different stresses and characterized by the secretion of various inflammatory factors referred to as the senescence-associated secretory phenotype (SASP). Here, we present evidence that the inflammasome sensor, NLRP1, is a key mediator of senescence induced by irradiation both in vitro and in vivo. The NLRP1 inflammasome promotes senescence by regulating the expression of p16, p21, p53, and SASP in Gasdermin D (GSDMD)-dependent manner as these responses are reduced in conditions of NLRP1 insufficiency or GSDMD inhibition. Mechanistically, the NLRP1 inflammasome is activated downstream of the cytosolic DNA sensor cGMP-AMP (cGAMP) synthase (cGAS) in response to genomic damage. These findings provide a rationale for inhibiting the NLRP1 inflammasome-GSDMD axis to treat senescence-driven disorders.

immunology↗

Short senolytic or senostatic interventions rescue progression of radiation-induced frailty and premature ageing in mice

Cancer survivors suffer from progressive frailty, multimorbidity and premature morbidity. We hypothesize that therapy-induced senescence and senescence progression via bystander effects is a significant cause of this premature ageing phenotype. Accordingly, the study addresses the question whether a short anti-senescence intervention is able to block progression of radiation-induced frailty and disability in a pre-clinical setting. Male mice were sub-lethally irradiated at 5 months of age and treated (or not) with either a senolytic drug (Navitoclax or dasatinib + quercetin) for 10 days or with the senostatic metformin for 10 weeks. Follow up was for one year. Treatments commencing within a month after irradiation effectively reduced frailty progression (p<0.05) and improved muscle (p<0.01) and liver (p<0.05) function as well as short-term memory (p<0.05) until advanced age with no need for repeated interventions. Senolytic interventions that started late, after radiation-induced premature frailty was manifest, still had beneficial effects on frailty (p<0.05) and short-term memory (p<0.05). Metformin was similarly effective as senolytics. At therapeutically achievable concentrations metformin acted as a senostatic neither via inhibition of mitochondrial complex I, nor via improvement of mitophagy or mitochondrial function, but by reducing non-mitochondrial ROS production via NOX4 inhibition in senescent cells. Our study suggests that the progression of adverse long-term health and quality-of-life effects of radiation exposure, as experienced by cancer survivors, might be rescued by short-term adjuvant anti-senescence interventions.

cancer biology↗