J S Talboom, M D De Both, M A Naymik, A M Schmidt, C R Lewis, W M Jepsen, A K Håberg, T Rundek, B E Levin, S Hoscheidt, Y Bolla, R D Brinton, N J Schork, M Hay, C A Barnes, E Glisky, L Ryan, M J Huentelman
{"title":"Two separate, large cohorts reveal potential modifiers of age-associated variation in visual reaction time performance.","authors":"J S Talboom, M D De Both, M A Naymik, A M Schmidt, C R Lewis, W M Jepsen, A K Håberg, T Rundek, B E Levin, S Hoscheidt, Y Bolla, R D Brinton, N J Schork, M Hay, C A Barnes, E Glisky, L Ryan, M J Huentelman","doi":"10.1038/s41514-021-00067-6","DOIUrl":"https://doi.org/10.1038/s41514-021-00067-6","url":null,"abstract":"<p><p>To identify potential factors influencing age-related cognitive decline and disease, we created MindCrowd. MindCrowd is a cross-sectional web-based assessment of simple visual (sv) reaction time (RT) and paired-associate learning (PAL). svRT and PAL results were combined with 22 survey questions. Analysis of svRT revealed education and stroke as potential modifiers of changes in processing speed and memory from younger to older ages (n<sub>total</sub> = 75,666, n<sub>women</sub> = 47,700, n<sub>men</sub> = 27,966; ages 18-85 years old, mean (M)<sub>Age</sub> = 46.54, standard deviation (SD)<sub>Age</sub> = 18.40). To complement this work, we evaluated complex visual recognition reaction time (cvrRT) in the UK Biobank (n<sub>total</sub> = 158,249 n<sub>women</sub> = 89,333 n<sub>men</sub> = 68,916; ages 40-70 years old, M<sub>Age</sub> = 55.81, SD<sub>Age</sub> = 7.72). Similarities between the UK Biobank and MindCrowd were assessed using a subset of MindCrowd (UKBb MindCrowd) selected to mirror the UK Biobank demographics (n<sub>total</sub> = 39,795, n<sub>women</sub> = 29,640, n<sub>men</sub> = 10,155; ages 40-70 years old, M<sub>Age</sub> = 56.59, SD<sub>Age</sub> = 8.16). An identical linear model (LM) was used to assess both cohorts. Analyses revealed similarities between MindCrowd and the UK Biobank across most results. Divergent findings from the UK Biobank included (1) a first-degree family history of Alzheimer's disease (FHAD) was associated with longer cvrRT. (2) Men with the least education were associated with longer cvrRTs comparable to women across all educational attainment levels. Divergent findings from UKBb MindCrowd included more education being associated with shorter svRTs and a history of smoking with longer svRTs from younger to older ages.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00067-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10610266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Autofluorescence as a noninvasive biomarker of senescence and advanced glycation end products in Caenorhabditis elegans.","authors":"Tomomi Komura, Mikihiro Yamanaka, Kohji Nishimura, Keita Hara, Yoshikazu Nishikawa","doi":"10.1038/s41514-021-00061-y","DOIUrl":"10.1038/s41514-021-00061-y","url":null,"abstract":"<p><p>To assess the utility of autofluorescence as a noninvasive biomarker of senescence in Caenorhabditis elegans, we measured the autofluorescence of individual nematodes using spectrofluorometry. The fluorescence of each worm increased with age. Animals with lower fluorescence intensity exhibited longer life expectancy. When proteins extracted from worms were incubated with sugars, the fluorescence intensity and the concentration of advanced glycation end products (AGEs) increased over time. Ribose enhanced these changes not only in vitro but also in vivo. The glycation blocker rifampicin suppressed this rise in fluorescence. High-resolution mass spectrometry revealed that vitellogenins accumulated in old worms, and glycated vitellogenins emitted six-fold higher fluorescence than naive vitellogenins. The increase in fluorescence with ageing originates from glycated substances, and therefore could serve as a useful noninvasive biomarker of AGEs. C. elegans can serve as a new model to look for anti-AGE factors and to study the relationship between AGEs and senescence.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8184826/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39072296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vijay R Varma, H Büşra Lüleci, Anup M Oommen, Sudhir Varma, Chad T Blackshear, Michael E Griswold, Yang An, Jackson A Roberts, Richard O'Brien, Olga Pletnikova, Juan C Troncoso, David A Bennett, Tunahan Çakır, Cristina Legido-Quigley, Madhav Thambisetty
{"title":"Abnormal brain cholesterol homeostasis in Alzheimer's disease-a targeted metabolomic and transcriptomic study.","authors":"Vijay R Varma, H Büşra Lüleci, Anup M Oommen, Sudhir Varma, Chad T Blackshear, Michael E Griswold, Yang An, Jackson A Roberts, Richard O'Brien, Olga Pletnikova, Juan C Troncoso, David A Bennett, Tunahan Çakır, Cristina Legido-Quigley, Madhav Thambisetty","doi":"10.1038/s41514-021-00064-9","DOIUrl":"https://doi.org/10.1038/s41514-021-00064-9","url":null,"abstract":"<p><p>The role of brain cholesterol metabolism in Alzheimer's disease (AD) remains unclear. Peripheral and brain cholesterol levels are largely independent due to the impermeability of the blood brain barrier (BBB), highlighting the importance of studying the role of brain cholesterol homeostasis in AD. We first tested whether metabolite markers of brain cholesterol biosynthesis and catabolism were altered in AD and associated with AD pathology using linear mixed-effects models in two brain autopsy samples from the Baltimore Longitudinal Study of Aging (BLSA) and the Religious Orders Study (ROS). We next tested whether genetic regulators of brain cholesterol biosynthesis and catabolism were altered in AD using the ANOVA test in publicly available brain tissue transcriptomic datasets. Finally, using regional brain transcriptomic data, we performed genome-scale metabolic network modeling to assess alterations in cholesterol biosynthesis and catabolism reactions in AD. We show that AD is associated with pervasive abnormalities in cholesterol biosynthesis and catabolism. Using transcriptomic data from Parkinson's disease (PD) brain tissue samples, we found that gene expression alterations identified in AD were not observed in PD, suggesting that these changes may be specific to AD. Our results suggest that reduced de novo cholesterol biosynthesis may occur in response to impaired enzymatic cholesterol catabolism and efflux to maintain brain cholesterol levels in AD. This is accompanied by the accumulation of nonenzymatically generated cytotoxic oxysterols. Our results set the stage for experimental studies to address whether abnormalities in cholesterol metabolism are plausible therapeutic targets in AD.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00064-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10642762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nicholas Holzscheck, Cassandra Falckenhayn, Jörn Söhle, Boris Kristof, Ralf Siegner, André Werner, Janka Schössow, Clemens Jürgens, Henry Völzke, Horst Wenck, Marc Winnefeld, Elke Grönniger, Lars Kaderali
{"title":"Modeling transcriptomic age using knowledge-primed artificial neural networks.","authors":"Nicholas Holzscheck, Cassandra Falckenhayn, Jörn Söhle, Boris Kristof, Ralf Siegner, André Werner, Janka Schössow, Clemens Jürgens, Henry Völzke, Horst Wenck, Marc Winnefeld, Elke Grönniger, Lars Kaderali","doi":"10.1038/s41514-021-00068-5","DOIUrl":"10.1038/s41514-021-00068-5","url":null,"abstract":"<p><p>The development of 'age clocks', machine learning models predicting age from biological data, has been a major milestone in the search for reliable markers of biological age and has since become an invaluable tool in aging research. However, beyond their unquestionable utility, current clocks offer little insight into the molecular biological processes driving aging, and their inner workings often remain non-transparent. Here we propose a new type of age clock, one that couples predictivity with interpretability of the underlying biology, achieved through the incorporation of prior knowledge into the model design. The clock, an artificial neural network constructed according to well-described biological pathways, allows the prediction of age from gene expression data of skin tissue with high accuracy, while at the same time capturing and revealing aging states of the pathways driving the prediction. The model recapitulates known associations of aging gene knockdowns in simulation experiments and demonstrates its utility in deciphering the main pathways by which accelerated aging conditions such as Hutchinson-Gilford progeria syndrome, as well as pro-longevity interventions like caloric restriction, exert their effects.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.4,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8169742/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10610243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yankun Lyu, Vipin K Verma, Younjee Lee, Iosif Taleb, Rachit Badolia, Thirupura S Shankar, Christos P Kyriakopoulos, Craig H Selzman, William Caine, Rami Alharethi, Sutip Navankasattusas, Thomas Seidel, Stavros G Drakos, Frank B Sachse
{"title":"Remodeling of t-system and proteins underlying excitation-contraction coupling in aging versus failing human heart.","authors":"Yankun Lyu, Vipin K Verma, Younjee Lee, Iosif Taleb, Rachit Badolia, Thirupura S Shankar, Christos P Kyriakopoulos, Craig H Selzman, William Caine, Rami Alharethi, Sutip Navankasattusas, Thomas Seidel, Stavros G Drakos, Frank B Sachse","doi":"10.1038/s41514-021-00066-7","DOIUrl":"https://doi.org/10.1038/s41514-021-00066-7","url":null,"abstract":"<p><p>It is well established that the aging heart progressively remodels towards a senescent phenotype, but alterations of cellular microstructure and their differences to chronic heart failure (HF) associated remodeling remain ill-defined. Here, we show that the transverse tubular system (t-system) and proteins underlying excitation-contraction coupling in cardiomyocytes are characteristically remodeled with age. We shed light on mechanisms of this remodeling and identified similarities and differences to chronic HF. Using left ventricular myocardium from donors and HF patients with ages between 19 and 75 years, we established a library of 3D reconstructions of the t-system as well as ryanodine receptor (RyR) and junctophilin 2 (JPH2) clusters. Aging was characterized by t-system alterations and sarcolemmal dissociation of RyR clusters. This remodeling was less pronounced than in HF and accompanied by major alterations of JPH2 arrangement. Our study indicates that targeting sarcolemmal association of JPH2 might ameliorate age-associated deficiencies of heart function.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00066-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38961236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dorela D Shuboni-Mulligan, Demarrius L Young, Julianie De La Cruz Minyety, Elizabeth Vera, Jeeva Munasinghe, Andrew J Gall, Mark R Gilbert, Terri S Armstrong, DeeDee K Smart
{"title":"Impact of age on the circadian visual system and the sleep-wake cycle in mus musculus.","authors":"Dorela D Shuboni-Mulligan, Demarrius L Young, Julianie De La Cruz Minyety, Elizabeth Vera, Jeeva Munasinghe, Andrew J Gall, Mark R Gilbert, Terri S Armstrong, DeeDee K Smart","doi":"10.1038/s41514-021-00063-w","DOIUrl":"https://doi.org/10.1038/s41514-021-00063-w","url":null,"abstract":"<p><p>Age plays a critical role in disease development and tolerance to cancer treatment, often leading to an increased risk of developing negative symptoms including sleep disturbances. Circadian rhythms and sleep become disrupted as organisms age. In this study, we explored the behavioral alterations in sleep, circadian rhythms, and masking using a novel video system and interrogate the long-term impact of age-based changes in the non-image forming visual pathway on brain anatomy. We demonstrated the feasibility and utility of the novel system and establish that older mice have disruptions in sleep, circadian rhythms, and masking behaviors that were associated with major negative volume alterations in the non-imaging forming visual system, critical for the induction and rhythmic expression of sleep. These results provide important insights into a mechanism, showing brain atrophy is linked to age in distinct non-image forming visual regions, which may predispose older individuals to developing circadian and sleep dysfunction when further challenged by disease or treatment.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00063-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38949955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marangelie Criado-Marrero, Niat T Gebru, Lauren A Gould, Danielle M Blazier, Yamile Vidal-Aguiar, Taylor M Smith, Salma S Abdelmaboud, Lindsey B Shelton, Xinming Wang, Jan Dahrendorff, David Beaulieu-Abdelahad, Chad A Dickey, Laura J Blair
{"title":"FKBP52 overexpression accelerates hippocampal-dependent memory impairments in a tau transgenic mouse model.","authors":"Marangelie Criado-Marrero, Niat T Gebru, Lauren A Gould, Danielle M Blazier, Yamile Vidal-Aguiar, Taylor M Smith, Salma S Abdelmaboud, Lindsey B Shelton, Xinming Wang, Jan Dahrendorff, David Beaulieu-Abdelahad, Chad A Dickey, Laura J Blair","doi":"10.1038/s41514-021-00062-x","DOIUrl":"https://doi.org/10.1038/s41514-021-00062-x","url":null,"abstract":"<p><p>Abnormal accumulation of hyperphosphorylated tau induces pathogenesis in neurodegenerative diseases, like Alzheimer's disease. Molecular chaperones with peptidyl-prolyl cis/trans isomerase (PPIase) activity are known to regulate these processes. Previously, in vitro studies have shown that the 52 kDa FK506-binding protein (FKBP52) interacts with tau inducing its oligomerization and fibril formation to promote toxicity. Thus, we hypothesized that increased expression of FKBP52 in the brains of tau transgenic mice would alter tau phosphorylation and neurofibrillary tangle formation ultimately leading to memory impairments. To test this, tau transgenic (rTg4510) and wild-type mice received bilateral hippocampal injections of virus overexpressing FKBP52 or GFP control. We examined hippocampal-dependent memory, synaptic plasticity, tau phosphorylation status, and neuronal health. This work revealed that rTg4510 mice overexpressing FKBP52 had impaired spatial learning, accompanied by long-term potentiation deficits and hippocampal neuronal loss, which was associated with a modest increase in total caspase 12. Together with previous studies, our findings suggest that FKBP52 may sensitize neurons to tau-mediated dysfunction via activation of a caspase-dependent pathway, contributing to memory and learning impairments.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00062-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9198059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Claudia E Rübe, Caroline Bäumert, Nadine Schuler, Anna Isermann, Zoé Schmal, Matthias Glanemann, Carl Mann, Harry Scherthan
{"title":"Human skin aging is associated with increased expression of the histone variant H2A.J in the epidermis.","authors":"Claudia E Rübe, Caroline Bäumert, Nadine Schuler, Anna Isermann, Zoé Schmal, Matthias Glanemann, Carl Mann, Harry Scherthan","doi":"10.1038/s41514-021-00060-z","DOIUrl":"https://doi.org/10.1038/s41514-021-00060-z","url":null,"abstract":"<p><p>Cellular senescence is an irreversible growth arrest that occurs as a result of damaging stimuli, including DNA damage and/or telomere shortening. Here, we investigate histone variant H2A.J as a new biomarker to detect senescent cells during human skin aging. Skin biopsies from healthy volunteers of different ages (18-90 years) were analyzed for H2A.J expression and other parameters involved in triggering and/or maintaining cellular senescence. In the epidermis, the proportions of H2A.J-expressing keratinocytes increased from ≈20% in young to ≈60% in aged skin. Inverse correlations between Ki67- and H2A.J staining in germinative layers may reflect that H2A.J-expressing cells having lost their capacity to divide. As cellular senescence is triggered by DNA-damage signals, persistent 53BP1-foci, telomere lengths, and telomere-associated damage foci were analyzed in epidermal keratinocytes. Only slight age-related telomere attrition and few persistent nuclear 53BP1-foci, occasionally colocalizing with telomeres, suggest that unprotected telomeres are not a significant cause of senescence during skin aging. Quantification of integrin-α6+ basal cells suggests that the number and function of stem/progenitor cells decreased during aging and their altered proliferation capacities resulted in diminished tissue renewal with epidermal thinning. Collectively, our findings suggest that H2A.J is a sensitive marker of epidermal aging in human skin.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00060-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25541300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ha-Neui Kim, Filipa Ponte, Aaron Warren, Rebecca Ring, Srividhya Iyer, Li Han, Maria Almeida
{"title":"A decrease in NAD<sup>+</sup> contributes to the loss of osteoprogenitors and bone mass with aging.","authors":"Ha-Neui Kim, Filipa Ponte, Aaron Warren, Rebecca Ring, Srividhya Iyer, Li Han, Maria Almeida","doi":"10.1038/s41514-021-00058-7","DOIUrl":"https://doi.org/10.1038/s41514-021-00058-7","url":null,"abstract":"<p><p>Age-related osteoporosis is caused by a deficit in osteoblasts, the cells that secrete bone matrix. The number of osteoblast progenitors also declines with age associated with increased markers of cell senescence. The forkhead box O (FoxO) transcription factors attenuate Wnt/β-catenin signaling and the proliferation of osteoprogenitors, thereby decreasing bone formation. The NAD<sup>+</sup>-dependent Sirtuin1 (Sirt1) deacetylates FoxOs and β-catenin in osteoblast progenitors and, thereby, increases bone mass. However, it remains unknown whether the Sirt1/FoxO/β-catenin pathway is dysregulated with age in osteoblast progenitors. We found decreased levels of NAD<sup>+</sup> in osteoblast progenitor cultures from old mice, associated with increased acetylation of FoxO1 and markers of cell senescence. The NAD<sup>+</sup> precursor nicotinamide riboside (NR) abrogated FoxO1 and β-catenin acetylation and several marker of cellular senescence, and increased the osteoblastogenic capacity of cells from old mice. Consistent with these effects, NR administration to C57BL/6 mice counteracted the loss of bone mass with aging. Attenuation of NAD<sup>+</sup> levels in osteoprogenitor cultures from young mice inhibited osteoblastogenesis in a FoxO-dependent manner. In addition, mice with decreased NAD<sup>+</sup> in cells of the osteoblast lineage lost bone mass at a young age. Together, these findings suggest that the decrease in bone formation with old age is due, at least in part, to a decrease in NAD<sup>+</sup> and dysregulated Sirt1/FoxO/β-catenin pathway in osteoblast progenitors. NAD<sup>+</sup> repletion, therefore, represents a rational therapeutic approach to skeletal involution.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00058-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25555253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Christopher T Turner, Juliana Bolsoni, Matthew R Zeglinski, Hongyan Zhao, Tatjana Ponomarev, Katlyn Richardson, Sho Hiroyasu, Erin Schmid, Anthony Papp, David J Granville
{"title":"Granzyme B mediates impaired healing of pressure injuries in aged skin.","authors":"Christopher T Turner, Juliana Bolsoni, Matthew R Zeglinski, Hongyan Zhao, Tatjana Ponomarev, Katlyn Richardson, Sho Hiroyasu, Erin Schmid, Anthony Papp, David J Granville","doi":"10.1038/s41514-021-00059-6","DOIUrl":"https://doi.org/10.1038/s41514-021-00059-6","url":null,"abstract":"<p><p>Pressure injuries (PIs), also known as bedsores or pressure ulcers, are a major cause of death and morbidity in the elderly. The serine protease, Granzyme B (GzmB), contributes to skin aging and impaired wound healing. Aging is a major risk factor for PIs; thus, the role of GzmB in PI pathogenesis was investigated. GzmB levels in human PI tissue and wound fluids were markedly elevated. A causative role for GzmB was assessed in GzmB knockout (GzmB-/-) and wild-type (WT) mice using a murine model of PI. An apolipoprotein E knockout (ApoE-/-) model of aging and vascular dysfunction was also utilized to assess GzmB in a relevant age-related model better resembling tissue perfusion in the elderly. PI severity displayed no difference between young GzmB-/- and WT mice. However, in aged mice, PI severity was reduced in mice lacking GzmB. Mechanistically, GzmB increased vascular wall inflammation and impaired extracellular matrix remodeling. Together, GzmB is an important contributor to age-dependent impaired PI healing.</p>","PeriodicalId":19334,"journal":{"name":"NPJ Aging and Mechanisms of Disease","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2021-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1038/s41514-021-00059-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25441895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}