Niedernhofer, Laura J.

Cellular senescence represents one of the major risk factors for chronic liver disease and contributes to morbidity, mortality, and increased healthcare spending. A relevant strategy for understanding the role of senescent cells in liver pathogenesis is to use genetic or pharmacological strategies to eliminate senescent cells. The combination of the senolytic drugs, Dasatinib and Quercetin (D+Q), effectively reduces senescent cell burden in multiple tissues, extending both healthspan and lifespan in mice, and alliviating obesity and age‐associated hepatic steatosis. The aim of this study was to investigate effects of D+Q treatment on livers of young and old female mice. A total of 40 mice, 20 young females (3‐months) and 20 old females (18‐months), was divided into 4 groups: Young (Y) mice treated with either D+Q or placebo and old (O) mice treated with D+Q or placebo. The treatment was performed for 3 consecutive days every 2 weeks over 10 weeks. Comparative analysis of hepatic miRNAs indicated that D+Q treatment significantly decreased levels of senescence‐specific miR‐126 expression in livers of old mice treated with D+Q compared to vehicle‐treated old mice (p=0.025), As expected, there was no effect of D+Q treatment in young animals. Analysis of miR‐126 target genes indicated that PI3K gene expression was significantly increased in response to D+Q treatment (p=0.003). Additionally, Akt1 and mTOR mRNA levels were increased in D+Q‐treated mice (p=0.008 and p=0.02, respectively). In summary, our data suggest that the mechanism of PI3K signaling pathway activation upon elimination of senescent cells by treatment with D+Q is mediated through downregulation of senescence‐specific miR‐126. Support or Funding Information This work is supported by National Institutes of Health (NIH) (R56AG061414, R15AG059190 and R03AG059846)

Advances in understanding fundamental processes of aging have led to a variety of investigational therapies to delay or prevent age‐related diseases and conditions. These geroscience therapeutics hold the promise of revolutionizing medical care of older adults by treating the complex syndromes of aging and preserving health and independence. A crucial bottleneck is the study of geroscience therapeutics in early‐stage, first‐in‐human, or proof‐of‐concept clinical trials. There is a limited pool of clinical investigators with the combination of knowledge and skills at the interface of clinical research, care of older adults, and aging biology needed to successfully design, fund, and implement geroscience trials. Current training pipelines are insufficient to meet the need. The sixth retreat of the National Institute on Aging R24 Geroscience Network brought together basic scientists, gerontologists, clinicians, and clinical researchers from the United States and Europe to discuss how to identify, recruit, and train investigators who can perform early‐stage clinical trials in geroscience. We present herein the group's consensus on necessary subject domains and competencies, identification of candidate learners, credentialing learners, and the efficient and rapid implementation of training programs. Foundations and funding agencies have crucial roles to play in catalyzing the development of these programs. Geriatrician investigators are indispensable but cannot meet the need alone. Translational geroscience training programs can create a cadre of groundbreaking investigators from a variety of backgrounds and foster institutional cultures supportive of multidisciplinary translational aging research to turn innovative ideas into transformative therapeutics that can improve the health and independence of older adults. J Am Geriatr Soc 67:1934–1939, 2019

ABSTRACT Previously, we demonstrated that intratumoral delivery of adenoviral vector encoding single‐chain (sc) IL‐23 (Ad.scIL‐23) was able to induce systemic antitumor immunity. Here, we examined the role of IL‐23 in diabetes in nonobese diabetic mice. Intravenous delivery of Ad.scIL‐23 did not accelerate the onset of hyperglycemia but instead resulted in the development of psoriatic arthritis. Ad.scIL‐23–treated mice developed erythema, scales, and thickening of the skin, as well as intervertebral disc degeneration and extensive synovial hypertrophy and loss of articular cartilage in the knees. Immunological analysis revealed activation of conventional T helper type 17 cells and IL‐17–producing γδ T cells along with a significant depletion and suppression of T cells in the pancreatic lymph nodes. Furthermore, treatment with anti–IL‐17 antibody reduced joint and skin psoriatic arthritis pathologies. Thus, these Ad.scIL‐23–treated mice represent a physiologically relevant model of psoriatic arthritis for understanding disease progression and for testing therapeutic approaches.—Flores, R. R., Carbo, L., Kim, E., Van Meter, M., De Padilla, C. M. L., Zhao, J., Colangelo, D., Yousefzadeh, M. J., Angelini, L. A., Zhang, L., Pola, E., Vo, N., Evans, C. H., Gambotto, A., Niedernhofer, L. J., Robbins, P. D. Adenoviral gene transfer of a single‐chain IL‐23 induces psoriatic arthritis–like symptoms in NOD mice. FASEB J. 33, 9505–9515 (2019). www.fasebj.org

Summary A serum biomarker of biological versus chronological age would have significant impact on clinical care. It could be used to identify individuals at risk of early‐onset frailty or the multimorbidities associated with old age. It may also serve as a surrogate endpoint in clinical trials targeting mechanisms of aging. Here, we identified MCP ‐1/ CCL 2, a chemokine responsible for recruiting monocytes, as a potential biomarker of biological age. Circulating monocyte chemoattractant protein‐1 ( MCP ‐1) levels increased in an age‐dependent manner in wild‐type ( WT ) mice. That age‐dependent increase was accelerated in Ercc1 −/Δ and Bubr1 H/H mouse models of progeria. Genetic and pharmacologic interventions that slow aging of Ercc1 −/Δ and WT mice lowered serum MCP ‐1 levels significantly. Finally, in elderly humans with aortic stenosis, MCP ‐1 levels were significantly higher in frail individuals compared to nonfrail. These data support the conclusion that MCP ‐1 can be used as a measure of mammalian biological age that is responsive to interventions that extend healthy aging.

Senolytic drugs are agents that selectively induce apoptosis of senescent cells. These cells accumulate in many tissues with aging and at sites of pathology in multiple chronic diseases. In studies in animals, targeting senescent cells using genetic or pharmacological approaches delays, prevents, or alleviates multiple age‐related phenotypes, chronic diseases, geriatric syndromes, and loss of physiological resilience. Among the chronic conditions successfully treated by depleting senescent cells in preclinical studies are frailty, cardiac dysfunction, vascular hyporeactivity and calcification, diabetes mellitus, liver steatosis, osteoporosis, vertebral disk degeneration, pulmonary fibrosis, and radiation‐induced damage. Senolytic agents are being tested in proof‐of‐concept clinical trials. To do so, new clinical trial paradigms for testing senolytics and other agents that target fundamental aging mechanisms are being developed, because use of long‐term endpoints such as lifespan or healthspan is not feasible. These strategies include testing effects on multimorbidity, accelerated aging‐like conditions, diseases with localized accumulation of senescent cells, potentially fatal diseases associated with senescent cell accumulation, age‐related loss of physiological resilience, and frailty. If senolytics or other interventions that target fundamental aging processes prove to be effective and safe in clinical trials, they could transform geriatric medicine by enabling prevention or treatment of multiple diseases and functional deficits in parallel, instead of one at a time.