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Calorie restriction (CR) with adequate nutrient intake is a potential geroprotective intervention. To advance this concept in humans, we tested the hypothesis that moderate CR in healthy young‐to‐middle‐aged individuals would reduce circulating biomarkers of cellular senescence, a fundamental mechanism of aging and aging‐related conditions. Using plasma specimens from the Comprehensive Assessment of Long‐term Effects of Reducing Intake of Energy (CALERIE™) phase 2 study, we found that CR significantly reduced the concentrations of several senescence biomarkers at 12 and 24 months compared to an ad libitum diet. Using machine learning, changes in biomarker concentrations emerged as important predictors of the change in HOMA‐IR and insulin sensitivity index at 12 and 24 months, and the change in resting metabolic rate residual at 12 months. Finally, using adipose tissue RNA‐sequencing data from a subset of participants, we observed a significant reduction in a senescence‐focused gene set in response to CR at both 12 and 24 months compared to baseline. Our results advance the understanding of the effects of CR in humans and further support a link between cellular senescence and metabolic health. [ABSTRACT FROM AUTHOR]

A robust and heterogenous secretory phenotype is a core feature of most senescent cells. In addition to mediators of age‐related pathology, components of the senescence associated secretory phenotype (SASP) have been studied as biomarkers of senescent cell burden and, in turn, biological age. Therefore, we hypothesized that circulating concentrations of candidate senescence biomarkers, including chemokines, cytokines, matrix remodeling proteins, and growth factors, could predict mortality in older adults. We assessed associations between plasma levels of 28 SASP proteins and risk of mortality over a median follow‐up of 6.3 years in 1923 patients 65 years of age or older with zero or one chronic condition at baseline. Overall, the five senescence biomarkers most strongly associated with an increased risk of death were GDF15, RAGE, VEGFA, PARC, and MMP2, after adjusting for age, sex, race, and the presence of one chronic condition. The combination of biomarkers and clinical and demographic covariates exhibited a significantly higher c‐statistic for risk of death (0.79, 95% confidence interval (CI): 0.76–0.82) than the covariates alone (0.70, CI: 0.67–0.74) (p < 0.001). Collectively, these findings lend further support to biomarkers of cellular senescence as informative predictors of clinically important health outcomes in older adults, including death. [ABSTRACT FROM AUTHOR]

Objective: To identify clusters of comorbidities in patients with rheumatoid arthritis (RA) using 4 methods and to compare to patients without RA. Methods: In this retrospective, population‐based study, residents of 8 Minnesota counties with prevalent RA as of January 1, 2015 were identified. Age‐, sex‐, and county‐matched non‐RA comparators were selected from the same underlying population. Diagnostic codes were retrieved for 5 years before January 1, 2015. Using 2 codes ≥30 days apart, 44 previously defined morbidities and 11 nonoverlapping chronic disease categories based on Clinical Classifications Software were defined. Unsupervised machine learning methods of interest included hierarchical clustering, factor analysis, K‐means clustering, and network analysis. Results: Two groups of 1,643 patients with and without RA (72% female; mean age 63.1 years in both groups) were studied. Clustering of comorbidities revealed strong associations among mental/behavioral comorbidities and among cardiovascular risk factors and diseases. The clusters were associated with age and sex. Differences between the 4 clustering methods were driven by comorbidities that are rare and those that were weakly associated with other comorbidities. Common comorbidities tended to group together consistently across approaches. The instability of clusters when using different random seeds or bootstrap sampling impugns the usefulness and reliability of these methods. Clusters of common comorbidities between RA and non‐RA cohorts were similar. Conclusion: Despite the higher comorbidity burden in patients with RA compared to the general population, clustering comorbidities did not identify substantial differences in comorbidity patterns between the RA and non‐RA cohorts. The instability of clustering methods suggests caution when interpreting clustering using 1 method. [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with few effective treatment options. We found a highly significant correlation between pregnancy‐associated plasma protein (PAPP)‐A expression in IPF lung tissue and disease severity as measured by various pulmonary and physical function tests. PAPP‐A is a metalloproteinase that enhances local insulin‐like growth factor (IGF) activity. We used primary cultures of normal adult human lung fibroblasts (NHLF) to test the hypothesis that PAPP‐A plays an important role in the development of pulmonary fibrosis. Treatment of NHLF with pro‐fibrotic transforming growth factor (TGF)‐β stimulated marked increases in IGF‐I mRNA expression (>20‐fold) and measurable IGF‐I levels in 72‐h conditioned medium (CM). TGF‐β treatment also increased PAPP‐A levels in CM fourfold (p = 0.004) and proteolytic activity ~2‐fold. There was an indirect effect of TGF‐β to stimulate signaling through the PI3K/Akt pathway, which was significantly inhibited by both IGF‐I‐inactivating and PAPP‐A inhibitory antibodies. Induction of senescence in NHLF increased PAPP‐A levels in CM 10‐fold (p = 0.006) with attendant increased proteolytic activity. Thus, PAPP‐A is a novel component of the senescent lung fibroblast secretome. In addition, NHLF secreted extracellular vehicles (EVs) with surface‐bound active PAPP‐A that were increased fivefold with senescence. Regulation of PAPP‐A and IGF signaling by TGF‐β and cell senescence suggests an interactive cellular mechanism underlying the resistance to apoptosis and the progression of fibrosis in IPF. Furthermore, PAPP‐A‐associated EVs may be a means of pro‐fibrotic, pro‐senescent communication with other cells in the lung and, thus, a potential therapeutic target for IPF. [ABSTRACT FROM AUTHOR]

The burden of senescent cells (SnCs), which do not divide but are metabolically active and resistant to death by apoptosis, is increased in older adults and those with chronic diseases. These individuals are also at the greatest risk for morbidity and mortality from SARS‐CoV‐2 infection. SARS‐CoV‐2 complications include cytokine storm and multiorgan failure mediated by the same factors as often produced by SnCs through their senescence‐associated secretory phenotype (SASP). The SASP can be amplified by infection‐related pathogen‐associated molecular profile factors. Senolytic agents, such as Fisetin, selectively eliminate SnCs and delay, prevent, or alleviate multiple disorders in aged experimental animals and animal models of human chronic diseases, including obesity, diabetes, and respiratory diseases. Senolytics are now in clinical trials for multiple conditions linked to SnCs, including frailty; obesity/diabetes; osteoporosis; and cardiovascular, kidney, and lung diseases, which are also risk factors for SARS‐CoV‐2 morbidity and mortality. A clinical trial is underway to test if senolytics decrease SARS‐CoV‐2 progression and morbidity in hospitalized older adults. We describe here a National Institutes of Health‐funded, multicenter, placebo‐controlled clinical trial of Fisetin for older adult skilled nursing facility (SNF) residents who have been, or become, SARS‐CoV‐2 rtPCR‐positive, including the rationale for targeting fundamental aging mechanisms in such patients. We consider logistic challenges of conducting trials in long‐term care settings in the SARS‐CoV‐2 era, including restricted access, consent procedures, methods for obtaining biospecimens and clinical data, staffing, investigational product administration issues, and potential solutions for these challenges. We propose developing a national network of SNFs engaged in interventional clinical trials. [ABSTRACT FROM AUTHOR]

Background: Failure of immunologic homeostasis and resultant hepatocyte destruction in autoimmune hepatitis (AIH) is likely the result of environmental triggers within a permissive genetic architecture. Aims: We aimed to identify risk factors associated with AIH in a well‐phenotyped AIH cohort. Methods: We prospectively collected environmental questionnaires from 358 AIH cases and 563 healthy controls. Response frequencies were compared using logistic regression, adjusting for age at recruitment, sex and education. Results: AIH cases were more likely to ever have a urinary tract infection (UTI) (53.6% vs 33.9%, P <.001) and recurrent UTI (more than 1 per year) (23.5% vs 15.9%, P =.002) compared to controls. Female cases more frequently had ever used oral contraceptives (83.0% vs 73.7%, P =.006), fewer pregnancies (median = 1 vs 3, P <.001) and less often used hormone replacement therapy compared to controls (28.5% vs 60.1%, P <.001). Current smoking was more prevalent in cases (18.9% vs 7.4%, P =.022), yet no difference according to historical smoking behaviours was observed. Finally, cases were less likely to have history of mumps (32.4% vs 53.1%, P =.011) and rheumatic fever (1.1% vs 4.4%, P =.028), but reported higher vaccination frequency to chicken pox (38% vs 28.1%), measles (66.5% vs 39.3%), mumps (58.7% vs 34.6%), rubella (55.3% vs 32.7%), pertussis (59.8% vs 40.1%) and pneumococcus (47.2% VS 39.4%) (P <.002). Conclusions: Environmental factors are important in AIH pathogenesis. Replication of these findings and prospective examination may provide new insight into AIH onset and outcomes. [ABSTRACT FROM AUTHOR]

Cellular senescence has emerged as a significant and potentially tractable mechanism of aging and multiple aging‐related conditions. Biomarkers of senescent cell burden, including molecular signals in circulating immune cells and the abundance of circulating senescence‐related proteins, have been associated with chronological age and clinical parameters of biological age in humans. The extent to which senescence biomarkers are affected by interventions that enhance health and function has not yet been examined. Here, we report that a 12‐week structured exercise program drives significant improvements in several performance‐based and self‐reported measures of physical function in older adults. Impressively, the expression of key markers of the senescence program, including p16,p21, cGAS, and TNFα, were significantly lowered in CD3+ T cells in response to the intervention, as were the circulating concentrations of multiple senescence‐related proteins. Moreover, partial least squares discriminant analysis showed levels of senescence‐related proteins at baseline were predictive of changes in physical function in response to the exercise intervention. Our study provides first‐in‐human evidence that biomarkers of senescent cell burden are significantly lowered by a structured exercise program and predictive of the adaptive response to exercise. [ABSTRACT FROM AUTHOR]

Background: Currently, there is no biologically based rationale for drug selection in migraine prophylactic treatment. Methods: To investigate the genetic variation underlying treatment response to verapamil prophylaxis, we selected 225 patients from a longitudinally established, deeply phenotyped migraine database (N = 5983), and collected uninterrupted quantitated verapamil treatment response data and DNA for these 225 cases. We recorded the number of headache days in the four weeks preceding treatment with verapamil and for four weeks, following completion of a treatment period with verapamil lasting at least five weeks. Whole‐exome sequencing (WES) was applied to a discovery cohort consisting of 21 definitive responders and 14 definitive non‐responders, and the identified single nucleotide polymorphisms (SNPs) showing significant association were genotyped in a separate confirmation cohort (185 verapamil treated patients). Statistical analysis of the WES data from the discovery cohort identified 524 SNPs associated with verapamil responsiveness (p < 0.01); among them, 39 SNPs were validated in the confirmatory cohort (n = 185) which included the full range of response to verapamil from highly responsive to not responsive. Results: Fourteen SNPs were confirmed by both percentage and arithmetic statistical approaches. Pathway and protein network analysis implicated myo‐inositol biosynthetic and phospholipase‐C second messenger pathways in verapamil responsiveness, emphasizing the earlier pathogenic understanding of migraine. No association was found between genetic variation in verapamil metabolic enzymes and treatment response. Conclusion: Our findings demonstrate that genetic analysis in well‐characterized subpopulations can yield important pharmacogenetic information pertaining to the mechanism of anti‐migraine prophylactic medications. [ABSTRACT FROM AUTHOR]

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/CCL2, 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 Bubr1H/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. [ABSTRACT FROM AUTHOR]

Background and Aim Primary sclerosing cholangitis (PSC) typically develops in middle-age adults. Little is known about phenotypic differences when PSC is diagnosed at various ages. Therefore, we sought to compare the clinical characteristics of a large PSC cohort based on the age when PSC was diagnosed. Methods We performed a multicenter retrospective review to compare the features of PSC among those diagnosed between 1-19 ( n = 95), 20-59 ( n = 662), and 60-79 years ( n = 102). Results Those with an early diagnosis (ED) of PSC were more likely to have small-duct PSC (13%) than those with a middle-age diagnosis (MD) (5%) and late diagnosis (LD) groups (2%), P < 0.01, and appeared to have a decrease risk of hepatobiliary malignancies: ED versus MD: hazard ratio (HR), 0.25; 95% confidence interval (CI) 0.06-1.03, and ED versus LD: HR, 0.07; 95% CI 0.01-0.62. Cholangiocarcinoma was diagnosed in 78 subjects (ED n = 0, MD n = 66, and LD n = 12) and was more likely to be diagnosed within a year after the PSC diagnosis among those found to have PSC late in life: ED 0% (0/95), MD 2% (14/662), and LD 6% (6/102), P = 0.02. Similarly, hepatic decompensation was more common among those with LD-PSC versus younger individuals: LD versus MD: HR, 1.64; 95% CI 0.98-2.70, and LD versus ED: HR, 2.26; 95% CI 1.02-5.05. Conclusions Those diagnosed with PSC early in life are more likely to have small-duct PSC and less likely to have disease-related complications. Clinicians should be vigilant for underlying cholangiocarcinoma among those with PSC diagnosed late in life. [ABSTRACT FROM AUTHOR]

Background & Aims Primary biliary cirrhosis ( PBC) is characterized by chronic cholestasis and disease-specific antimitochondrial antibodies ( AMA). A high prevalence of AMAs in first-degree relatives ( FDRs) of PBC probands has been reported, although the natural history of such patients has not been described. We aimed to assess the risk of developing PBC in AMA+ FDRs of patients with PBC. Methods First-degree relatives recruited to the Mayo Clinic PBC Genetic Epidemiology Registry and Biorepository were followed for disease onset after recruitment. Development of PBC was ascertained via self-report during a telephone interview and/or via proband report on a questionnaire. Chi-squared test and t-test were used to assess the differences between categorical and continuous variables respectively. A mixed-effects model was used to assess the change in biochemical profiles over time. Results Forty AMA+ and 423 AMA− subjects were included and followed for a median of 8.9 and 8.4 years respectively. Overall, 3% ( n = 15) of FDRs were diagnosed with PBC, and AMA+ FDRs had a higher risk than AMA− FDRs (24% vs. 0.7%, P < 0.01). However, among undiagnosed FDRs, only 4% of AMA+ ( n = 1) and 0.4% of AMA− ( n = 1) FDRs were diagnosed with PBC ( P = 0.17) during the follow-up period. None of the AMA+ FDRs with normal alkaline phosphatase at baseline developed PBC in follow-up. Conclusions Our results suggest a low risk of developing PBC over time in FDRs of patients with PBC, particularly those without biochemical evidence of cholestasis at baseline. These data are useful in counselling and reassuring relatives of their overall favourable prognosis. [ABSTRACT FROM AUTHOR]

The damaging cholestasis inherent to primary sclerosing cholangitis (PSC) results from bile duct stricturing because of progressive fibrosis. The matrix metalloproteinase 3 (MMP3) degrades a wide range of matrix components and is expressed by activated liver stellate cells, and so is a candidate for involvement with the fibrotic processes underlying PSC. Moreover, the MMP3 gene harbours polymorphisms associated with variation in its activity directly impacting clinical phenotypes. We aimed to examine the influence of MMP3 polymorphisms on PSC risk and progression. Nine single nucleotide polymorphisms (SNPs) tagging the common genetic variation of MMP3 were genotyped in 266 PSC patients and 407 controls. SNPs and inferred haplotypes were assessed for PSC association by logistic regression and score tests. The effect of SNPs on survival to liver transplant or death was analysed using Cox regression, and Kaplan-Meier curves were constructed. No association of PSC with individual SNPs or haplotypes of MMP3 was detected. However, progression to death or liver transplant was significantly associated with homozygosity for minor alleles of rs522616, rs650108 and rs683878, particularly among PSC patients with concurrent ulcerative colitis (UC) (strongest in redundant SNPs rs650108/rs683878, hazard ratio=3.23, 95% confidence interval 1.45-7.25, P=0.004). Genetic variation in MMP3 influences PSC progression, possibly in the context of coexisting UC. While the functional variants and specific mechanisms remain unknown, this finding implicates the turnover of the extracellular matrix as an important and variable component of PSC pathogenesis. Efforts to understand this process could form the basis for developing effective treatments, which are currently lacking for PSC. [ABSTRACT FROM AUTHOR]