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1.
Artigo em Inglês | MEDLINE | ID: mdl-38724839

RESUMO

INTRODUCTION: Brodalumab is a human interleukin-17 receptor A antagonist indicated for the treatment of moderate-to-severe plaque psoriasis in adult patients who are candidates for systemic therapy or phototherapy and have failed to respond or have lost response to other systemic therapies. Although the US prescribing information for brodalumab includes a boxed warning regarding suicidal ideation and behavior, no causal association has been demonstrated. Here, we summarize 5 years of pharmacovigilance data, from August 15, 2017, through August 14, 2022, reported to Ortho Dermatologics by US patients and healthcare providers. METHODS: Prevalence of the most common adverse events (AEs) listed in the brodalumab package insert (incidence ≥ 1%) and AEs of special interest are described. Brodalumab exposure was estimated as the time from the first to last prescription-dispensing authorization dates. Data were collected from 4744 patients in the USA, with an estimated exposure of 5815 patient-years. RESULTS: Over 5 years, 11 cases of adjudicated major adverse cardiovascular events were reported (0.23 events/100 patients), a rate lower than that experienced by patients in the international Psoriasis Longitudinal Assessment and Registry. There were 106 serious infections. No serious fungal infections were reported. There were 40 confirmed and 2 suspected COVID-19 cases, with no new COVID-19-related deaths. Of 49 reported malignancies among 42 patients, 3 were deemed possibly related to brodalumab. No completed suicides and no new suicidal attempts were reported. CONCLUSION: Five-year pharmacovigilance data are consistent with the established safety profile reported in long-term clinical trials and previous pharmacovigilance reports, with no new safety signals.


Brodalumab is an injectable treatment approved for moderate-to-severe plaque psoriasis in adults who lacked response to previous treatments. In the USA, brodalumab is only available under a Risk Evaluation and Mitigation Strategy for increased suicidality risks; however, findings from 5 years of real-world safety data have demonstrated a lack of association. In this report, we discuss safety findings reported by US patients and healthcare providers for 4744 patients treated with brodalumab over 5 years. Joint pain (known as arthralgia) was the most common safety finding, with 122 cases reported over 5 years. Other safety findings of interest across 5 years included 106 serious infections (defined as prolonged infections or infections requiring treatment), 54 cases of depression, 49 cases of cancer (in 42 patients), 40 confirmed cases of COVID-19, and 11 cases of major cardiovascular events (such as stroke or heart attack). No completed suicides occurred throughout 5 years, and no new suicidal attempts were reported in year 5. In indirect comparisons with safety data from patients with psoriasis receiving or eligible to receive similar treatments, brodalumab was not associated with an increased risk of serious infection, cancer, major cardiovascular events, or inflammatory bowel disease. Taken together, these data are consistent with safety findings from long-term clinical trials and previous safety reports of brodalumab.

2.
Hum Mol Genet ; 32(11): 1826-1835, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-36715159

RESUMO

Berardinelli-Seip congenital lipodystrophy type 2 (CGL2) is a very rare human genetic disorder with potential significance to the understanding of the pathobiology of aging. CGL2 patients display characteristic progeroid features and suffer from type 2 diabetes, insulin resistance and fatty liver. In this study, we profiled genome-wide DNA methylation levels in CGL2 patients with BSCL2 mutations to study epigenetic age acceleration and DNA methylation alterations. This analysis revealed significant age acceleration in blood DNA of CGL2 patients using both first- and second-generation epigenetic clocks. We also observed a shortened lifespan of Caenorhabditis elegans following knockdown of the BSCL2 homolog seip-1 on a daf-16/forkhead box, class O mutant background. DNA methylation analysis revealed significant differentially methylated sites enriched for lyase activity, kinase regulator activity, protein kinase regulator activity and kinase activator activity. We could also observe significant hypomethylation in the promoter of the dual specificity phosphatase 22 gene when comparing CGL2 patients versus controls. We conclude that in line with the observed progeroid features, CGL2 patients exhibit significant epigenetic age acceleration and DNA methylation alterations that might affect pathways/genes of potential relevance to the disease.


Assuntos
Diabetes Mellitus Tipo 2 , Subunidades gama da Proteína de Ligação ao GTP , Lipodistrofia Generalizada Congênita , Lipodistrofia , Humanos , Lipodistrofia Generalizada Congênita/genética , Metilação de DNA/genética , Diabetes Mellitus Tipo 2/genética , Mutação , Envelhecimento/genética , Epigênese Genética , Lipodistrofia/genética
3.
Aging Cell ; 21(6): e13646, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35645319

RESUMO

Older age and underlying conditions such as diabetes/obesity or immunosuppression are leading host risk factors for developing severe complications from COVID-19 infection. The pathogenesis of COVID-19-related cytokine storm, tissue damage, and fibrosis may be interconnected with fundamental aging processes, including dysregulated immune responses and cellular senescence. Here, we examined effects of key cytokines linked to cellular senescence on expression of SARS-CoV-2 viral entry receptors. We found exposure of human umbilical vein endothelial cells (HUVECs) to the inflammatory cytokines, TNF-α + IFN-γ or a cocktail of TNF-α + IFN-γ + IL-6, increased expression of ACE2/DPP4, accentuated the pro-inflammatory senescence-associated secretory phenotype (SASP), and decreased cellular proliferative capacity, consistent with progression towards a cellular senescence-like state. IL-6 by itself failed to induce substantial effects on viral entry receptors or SASP-related genes, while synergy between TNF-α and IFN-γ initiated a positive feedback loop via hyper-activation of the JAK/STAT1 pathway, causing SASP amplification. Breaking the interactive loop between senescence and cytokine secretion with JAK inhibitor ruxolitinib or antiviral drug remdesivir prevented hyper-inflammation, normalized SARS-CoV-2 entry receptor expression, and restored HUVECs proliferative capacity. This loop appears to underlie cytokine-mediated viral entry receptor activation and links with senescence and hyper-inflammation.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Interferon gama , SARS-CoV-2 , Fator de Necrose Tumoral alfa , COVID-19/virologia , Citocinas/imunologia , Sinergismo Farmacológico , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/virologia , Interferon gama/farmacologia , Interleucina-6/metabolismo , Receptores Virais/metabolismo , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , Fator de Transcrição STAT1/biossíntese , Fator de Transcrição STAT1/imunologia , Fator de Necrose Tumoral alfa/farmacologia
4.
J Med Genet ; 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534204

RESUMO

BACKGROUND: Werner syndrome (WS) is an autosomal recessive progeroid syndrome caused by variants in WRN. The International Registry of Werner Syndrome has identified biallelic pathogenic variants in 179/188 cases of classical WS. In the remaining nine cases, only one heterozygous pathogenic variant has been identified. METHODS: Targeted long-read sequencing (T-LRS) on an Oxford Nanopore platform was used to search for a second pathogenic variant in WRN. Previously, T-LRS was successfully used to identify missing variants and analyse complex rearrangements. RESULTS: We identified a second pathogenic variant in eight of nine unsolved WS cases. In five cases, T-LRS identified intronic splice variants that were confirmed by either RT-PCR or exon trapping to affect splicing; in one case, T-LRS identified a 339 kbp deletion, and in two cases, pathogenic missense variants. Phasing of long reads predicted all newly identified variants were on a different haplotype than the previously known variant. Finally, in one case, RT-PCR previously identified skipping of exon 20; however, T-LRS did not detect a pathogenic DNA sequence variant. CONCLUSION: T-LRS is an effective method for identifying missing pathogenic variants. Although limitations with computational prediction algorithms can hinder the interpretation of variants, T-LRS is particularly effective in identifying intronic variants.

5.
Aging Cell ; 21(2): e13555, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35045206

RESUMO

Hutchinson-Gilford Progeria Syndrome (HGPS) is an extremely rare genetic disorder caused by mutations in the LMNA gene and characterized by premature and accelerated aging beginning in childhood. In this study, we performed the first genome-wide methylation analysis on blood DNA of 15 patients with progeroid laminopathies using Infinium Methylation EPIC arrays including 8 patients with classical HGPS. We could observe DNA methylation alterations at 61 CpG sites as well as 32 significant regions following a 5 Kb tiling analysis. Differentially methylated probes were enriched for phosphatidylinositol biosynthetic process, phospholipid biosynthetic process, sarcoplasm, sarcoplasmic reticulum, phosphatase regulator activity, glycerolipid biosynthetic process, glycerophospholipid biosynthetic process, and phosphatidylinositol metabolic process. Differential methylation analysis at the level of promoters and CpG islands revealed no significant methylation changes in blood DNA of progeroid laminopathy patients. Nevertheless, we could observe significant methylation differences in classic HGPS when specifically looking at probes overlapping solo-WCGW partially methylated domains. Comparing aberrantly methylated sites in progeroid laminopathies, classic Werner syndrome, and Down syndrome revealed a common significantly hypermethylated region in close vicinity to the transcription start site of a long non-coding RNA located anti-sense to the Catenin Beta Interacting Protein 1 gene (CTNNBIP1). By characterizing epigenetically altered sites, we identify possible pathways/mechanisms that might have a role in the accelerated aging of progeroid laminopathies.


Assuntos
Progéria , Síndrome de Werner , Envelhecimento/genética , DNA/genética , DNA/metabolismo , Metilação de DNA/genética , Humanos , Lamina Tipo A/genética , Lamina Tipo A/metabolismo , Mutação , Progéria/genética , Progéria/metabolismo , Síndrome de Werner/genética
6.
Geroscience ; 43(1): 181-196, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33595768

RESUMO

There is tremendous variation in biological traits, and much of it is not accounted for by variation in DNA sequence, including human diseases and lifespan. Emerging evidence points to differences in the execution of the genetic program as a key source of variation, be it stochastic variation or programmed variation. Here we discuss variation in gene expression as an intrinsic property and how it could contribute to variation in traits, including the rate of aging. The review is divided into sections describing the historical context and evidence to date for nongenetic variation, the different approaches that may be used to detect nongenetic variation, and recent findings showing that the amount of variation in gene expression can be both genetically programmed and epigenetically controlled. Finally, we present evidence that changes in cell-to-cell variation in gene expression emerge as part of the aging process and may be linked to disease vulnerability as a function of age. These emerging concepts are likely to be important across the spectrum of biomedical research and may well underpin what we understand as biological aging.


Assuntos
Envelhecimento , Longevidade , Envelhecimento/genética , Expressão Gênica , Humanos , Longevidade/genética , Fenótipo
7.
Geroscience ; 43(3): 1481-1496, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33428109

RESUMO

SMAD4 encodes a member of the SMAD family of proteins involved in the TGF-ß signaling pathway. Potentially heritable, autosomal dominant, gain-of-function heterozygous variants of SMAD4 cause a rare developmental disorder, the Myhre syndrome, which is associated with a wide range of developmental and post-developmental phenotypes that we now characterize as a novel segmental progeroid syndrome. Whole-exome sequencing of a patient referred to our International Registry of Werner Syndrome revealed a heterozygous p.Arg496Cys variant of the SMAD4 gene. To investigate the role of SMAD4 mutations in accelerated senescence, we generated cellular models overexpressing either wild-type SMAD4 or mutant SMAD4-R496C in normal skin fibroblasts. We found that cells expressing the SMAD4-R496C mutant exhibited decreased proliferation and elevated expression of cellular senescence and inflammatory markers, including IL-6, IFNγ, and a TGF-ß target gene, PAI-1. Here we show that transient exposure to TGF-ß, an inflammatory cytokine, followed by chronic IFNγ stimulation, accelerated rates of senescence that were associated with increased DNA damage foci and SMAD4 expression. TGF-ß, IFNγ, or combinations of both were not sufficient to reduce proliferation rates of fibroblasts. In contrast, TGF-ß alone was able to induce preadipocyte senescence via induction of the mTOR protein. The mTOR inhibitor rapamycin mitigated TGF-ß-induced expression of p21, p16, and DNA damage foci and improved replicative potential of preadipocytes, supporting the cell-specific response to this cytokine. These findings collectively suggest that persistent DNA damage and cross-talk between TGF-ß/IFNγ pathways contribute to a series of molecular events leading to cellular senescence and a segmental progeroid syndrome.


Assuntos
Senescência Celular , Dano ao DNA , Senescência Celular/genética , Criptorquidismo , Dano ao DNA/genética , Fácies , Transtornos do Crescimento , Deformidades Congênitas da Mão , Humanos , Deficiência Intelectual , Mutação , Proteína Smad4/genética , Fator de Crescimento Transformador beta/genética
8.
J Gerontol A Biol Sci Med Sci ; 76(2): 253-259, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33295962

RESUMO

The purpose of this early contribution to the new Fellows Forum of this pioneering journal for what is now called Geroscience is to provide an example of how the author's interest in using the emerging tools of human genetics has led to strong support for one of the hallmarks of aging-Genomic Instability. We shall also briefly review our emerging interests in the genetic analysis of what we have called Antigeroid Syndromes. While there has been significant progress in that direction via genetic studies of centenarians, the search for genetic pathways that make individuals unusually resistant or resilient to the ravages of specific geriatric disorders has been comparatively neglected. We refer to these disorders as Unimodal Antigeroid Syndromes. It is our hope that our young colleagues will consider research efforts in that direction.


Assuntos
Envelhecimento/genética , Instabilidade Genômica , Síndrome de Werner/genética , Doença de Alzheimer/genética , Síndrome de Cockayne/genética , Síndrome de Cockayne/patologia , Doença da Artéria Coronariana/genética , Diabetes Mellitus/genética , Feminino , Pesquisa em Genética , Humanos , Masculino , Mutação , Fenótipo , Progéria/genética , Progéria/patologia , Síndrome , Síndrome de Werner/patologia
9.
Aging Pathobiol Ther ; 2(2): 101-105, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32954377

RESUMO

Segmental progeroid syndromes are groups of genetic disorders with multiple features resembling accelerated aging. The International Registry of Werner Syndrome (Seattle, WA) recruits pedigrees of progeroid syndromes from all over the world. We identified two novel LMNA mutations, p.Asp300Gly in a patient from Myanmar, and p.Asn466Lys, in a patient from Greece. Both were referred to our Registry for the genetic diagnosis because of the accelerated aged-appearance and cardiac complications. LMNA mutations are the second most common genetic cause of progeroid syndromes after WRN mutations in our Registry. As the next generation sequencing becomes readily available, we expect to identify more cases of rare genetic diseases in the developing countries.

11.
J Gerontol A Biol Sci Med Sci ; 75(12): 2295-2298, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31957802

RESUMO

Cell-to-cell variation in gene expression increases among homologous cells within multiple tissues during aging. We call this phenomenon variegated gene expression (VGE). Long, healthy life requires robust and coordinated gene expression. We posit that nature may have evolved VGE as a bet-hedging mechanism to protect reproductively active populations. The price we may pay is accelerated aging. That hypothesis will require the demonstration that genetic loci are capable of modulating degrees of VGE. While loci controlling VGE in yeast and genes controlling interindividual variation in gene expression in Caenorhabditis elegans have been identified, there has been no compelling evidence for the role of specific genetic loci in modulations of VGE of specific targets in humans. With the assistance of a core facility, we used a customized library of siRNA constructs to screen 1,195 human genes to identify loci contributing to the control of VGE of a gene with relevance to the biology of aging. We identified approximately 50 loci controlling VGE of the prolongevity gene, SIRT1. Because of its partial homology to FOXO3A, a variant of which is enriched in centenarians, our laboratory independently confirmed that the knockdown of FOXF2 greatly diminished VGE of SIRT1 but had little impact upon the VGE of WRN. While the role of these VGE-altering genes on aging in vivo remains to be determined, we hypothesize that some of these genes can be targeted to increase functionality during aging.


Assuntos
Envelhecimento/genética , Fatores de Transcrição Forkhead/genética , Expressão Gênica/fisiologia , Sirtuína 1/genética , Linhagem Celular , Células Cultivadas , Epigênese Genética , Biblioteca Gênica , Humanos , RNA Interferente Pequeno/genética
12.
DNA Cell Biol ; 39(1): 50-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31750734

RESUMO

POLD1 encodes the catalytic subunit of DNA polymerase delta (Polδ), the major lagging strand polymerase, which also participates in DNA repair. Mutations affecting the exonuclease domain increase the risk of various cancers, while mutations that change the polymerase active site cause a progeroid syndrome called mandibular hypoplasia, deafness, progeroid features, and lipodystrophy (MDPL) syndrome. We generated a set of catalytic subunit of human telomerase (hTERT)-immortalized human fibroblasts expressing wild-type or mutant POLD1 using the retroviral LXSN vector system. In the resulting cell lines, expression of endogenous POLD1 was suppressed in favor of the recombinant POLD1. The siRNA screening of DNA damage-related genes revealed that fibroblasts expressing D316H and S605del POLD1 were more sensitive to knockdowns of ribonuclease reductase (RNR) components, RRM1 and RRM2 in the presence of hydroxyurea (HU), an RNR inhibitor. On the contrary, SAMHD1 siRNA, which increases the concentration of dNTPs, increased growth of wild type, D316H, and S605del POLD1 fibroblasts. Hypersensitivity to dNTP synthesis inhibition in POLD1 mutant lines was confirmed using gemcitabine. Our finding is consistent with the notion that reduced dNTP concentration negatively affects the cell growth of hTERT fibroblasts expressing exonuclease and polymerase mutant POLD1.


Assuntos
DNA Polimerase III/genética , Desoxirribonucleotídeos/metabolismo , Fibroblastos/metabolismo , Mutação , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , DNA Polimerase III/antagonistas & inibidores , DNA Polimerase III/metabolismo , Surdez/genética , Surdez/metabolismo , Exonucleases/genética , Exonucleases/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Hidroxiureia/farmacologia , Lipodistrofia/genética , Lipodistrofia/metabolismo , Lipodistrofia/patologia , Interferência de RNA , Proteína 1 com Domínio SAM e Domínio HD/genética , Proteína 1 com Domínio SAM e Domínio HD/metabolismo , Síndrome
13.
Aging Cell ; 18(5): e12995, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31259468

RESUMO

Werner Syndrome (WS) is an adult-onset segmental progeroid syndrome. Bisulfite pyrosequencing of repetitive DNA families revealed comparable blood DNA methylation levels between classical (18 WRN-mutant) or atypical WS (3 LMNA-mutant and 3 POLD1-mutant) patients and age- and sex-matched controls. WS was not associated with either age-related accelerated global losses of ALU, LINE1, and α-satellite DNA methylations or gains of rDNA methylation. Single CpG methylation was analyzed with Infinium MethylationEPIC arrays. In a correspondence analysis, atypical WS samples clustered together with the controls and were clearly separated from classical WS, consistent with distinct epigenetic pathologies. In classical WS, we identified 659 differentially methylated regions (DMRs) comprising 3,656 CpG sites and 613 RefSeq genes. The top DMR was located in the HOXA4 promoter. Additional DMR genes included LMNA, POLD1, and 132 genes which have been reported to be differentially expressed in WRN-mutant/depleted cells. DMRs were enriched in genes with molecular functions linked to transcription factor activity and sequence-specific DNA binding to promoters transcribed by RNA polymerase II. We propose that transcriptional misregulation of downstream genes by the absence of WRN protein contributes to the variable premature aging phenotypes of WS. There were no CpG sites showing significant differences in DNA methylation changes with age between WS patients and controls. Genes with both WS- and age-related methylation changes exhibited a constant offset of methylation between WRN-mutant patients and controls across the entire analyzed age range. WS-specific epigenetic signatures occur early in life and do not simply reflect an acceleration of normal epigenetic aging processes.


Assuntos
Envelhecimento/genética , Epigênese Genética/genética , Síndrome de Werner/genética , Humanos , Metilação , Mutação , Helicase da Síndrome de Werner/genética
14.
Mol Genet Genomic Med ; 6(6): 1148-1156, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30393977

RESUMO

BACKGROUND: Cerebroretinal microangiopathy with calcifications and cysts (CRMCC) is an autosomal recessive disorder caused by pathogenic variants of the conserved telomere maintenance component 1 (CTC1) gene. The CTC1 forms the telomeric capping complex, CST, which functions in telomere homeostasis and replication. METHODS: A Brazilian pedigree and an Australian pedigree were referred to the International Registry of Werner Syndrome (Seattle, WA, USA), with clinical features of accelerated aging and recurrent bone fractures. Whole exome sequencing was performed to identify the genetic causes. RESULTS: Whole exome sequencing of the Brazilian pedigree revealed compound heterozygous pathogenic variants in CTC1: a missense mutation (c.2959C>T, p.Arg987Trp) and a novel stop codon change (c.322C>T, p.Arg108*). The Australian patient carried two novel heterozygous CTC1 variants, c.2916G>T, p.Val972Gly and c.2926G>T, p.Val976Phe within the same allele. Both heterozygous variants were inherited from the unaffected father, excluding the diagnosis of CRMCC in this pedigree. Cell biological studies demonstrated accumulation of double strand break foci in lymphoblastoid cell lines derived from the patients. Increased DSB foci were extended to non-telomeric regions of the genome, in agreement with previous biochemical studies showing a preferential binding of CTC1 protein to GC-rich sequences. CONCLUSION: CTC1 pathogenic variants can present with unusual manifestations of progeria accompanied with recurrent bone fractures. Further studies are needed to elucidate the disease mechanism leading to the clinical presentation with intra-familial variations of CRMCC.


Assuntos
Fraturas Ósseas/genética , Mutação , Fenótipo , Proteínas de Ligação a Telômeros/genética , Síndrome de Werner/genética , Adulto , Linhagem Celular , Quebras de DNA de Cadeia Dupla , Feminino , Fraturas Ósseas/patologia , Sequência Rica em GC , Instabilidade Genômica , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Ligação Proteica , Telômero/genética , Proteínas de Ligação a Telômeros/metabolismo , Síndrome de Werner/patologia
15.
J Clin Aesthet Dermatol ; 11(9): 28-31, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30319728

RESUMO

Background: Ad-hoc reports within clinical studies of imiquimod for the treatment of actinic keratosis (AK) have suggested the drug can improve both skin texture and overall signs of photodamage. Objective: We sought to assess the efficacy and tolerability of imiquimod 3.75% and 2.5% cream for the treatment of photodamage in patients with AK of the full face or balding scalp. Methods: A meta-analysis of four identical multicenter, randomized, double-blind, vehicle-controlled studies was conducted. The studies included a total of 969 adult subjects (aged 33-91 years) with 5 to 20 visible lesions or palpable AKs in an area exceeding 25cm2 on either the face or balding scalp. Patients were randomized to imiquimod 3.75%, imiquimod 2.5%, or vehicle cream (1:1:1). Up to two packets (250mg each) were applied per dose once daily for two two-week treatment cycles, separated by a two-week no-treatment interval. Photodamage improvement was assessed at study end based on subjects' baseline assessments using a seven-point scale. Local skin reactions were recorded throughout the study. Results: Combined Investigator's Global Integrated Photodamage (IGIP) score was "significantly" or "much" improved in 57.6 percent (n=175) of patients treated with imiquimod 2.5% cream and in 69.6 percent (n=208) of patients treated with imiquimod 3.75% cream versus in 25.7 percent (n=76) of patients treated with the vehicle. Mean IGIP scores at end of study were 1.67, 1.98, and 0.73, respectively (both actives P<0.0001 versus vehicle). Conclusion: Both imiquimod 2.5% and 3.75% creams showed a positive effect on photodamage when compared with the vehicle cream.

16.
Aging (Albany NY) ; 10(7): 1758-1775, 2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-30048243

RESUMO

DNA methylation (DNAm)-based biomarkers of aging have been developed for many tissues and organs. However, these biomarkers have sub-optimal accuracy in fibroblasts and other cell types used in ex vivo studies. To address this challenge, we developed a novel and highly robust DNAm age estimator (based on 391 CpGs) for human fibroblasts, keratinocytes, buccal cells, endothelial cells, lymphoblastoid cells, skin, blood, and saliva samples. High age correlations can also be observed in sorted neurons, glia, brain, liver, and even bone samples. Gestational age correlates with DNAm age in cord blood. When used on fibroblasts from Hutchinson Gilford Progeria Syndrome patients, this age estimator (referred to as the skin & blood clock) uncovered an epigenetic age acceleration with a magnitude that is below the sensitivity levels of other DNAm-based biomarkers. Furthermore, this highly sensitive age estimator accurately tracked the dynamic aging of cells cultured ex vivo and revealed that their proliferation is accompanied by a steady increase in epigenetic age. The skin & blood clock predicts lifespan and it relates to many age-related conditions. Overall, this biomarker is expected to become useful for forensic applications (e.g. blood or buccal swabs) and for a quantitative ex vivo human cell aging assay.


Assuntos
Relógios Biológicos/fisiologia , Células Sanguíneas/fisiologia , Epigênese Genética/fisiologia , Progéria/metabolismo , Fenômenos Fisiológicos da Pele , Envelhecimento/fisiologia , Senescência Celular/fisiologia , Metilação de DNA , Sangue Fetal/citologia , Fibroblastos/fisiologia , Regulação da Expressão Gênica/fisiologia , Humanos
17.
Hum Mutat ; 39(2): 255-265, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29105242

RESUMO

Pathogenic variants in genes, which encode DNA repair and damage response proteins, result in a number of genomic instability syndromes with features of accelerated aging. ERCC4 (XPF) encodes a protein that forms a complex with ERCC1 and is required for the 5' incision during nucleotide excision repair. ERCC4 is also FANCQ, illustrating a critical role in interstrand crosslink repair. Pathogenic variants in this gene cause xeroderma pigmentosum, XFE progeroid syndrome, Cockayne syndrome (CS), and Fanconi anemia. We performed massive parallel sequencing for 42 unsolved cases submitted to the International Registry of Werner Syndrome. Two cases, each carrying two novel heterozygous ERCC4 variants, were identified. The first case was a compound heterozygote for: c.2395C > T (p.Arg799Trp) and c.388+1164_792+795del (p.Gly130Aspfs*18). Further molecular and cellular studies indicated that the ERCC4 variants in this patient are responsible for a phenotype consistent with a variant of CS. The second case was heterozygous for two variants in cis: c.[1488A > T; c.2579C > A] (p.[Gln496His; Ala860Asp]). While the second case also had several phenotypic features of accelerated aging, we were unable to provide biological evidence supporting the pathogenic roles of the associated ERCC4 variants. Precise genetic causes and disease mechanism of the second case remains to be determined.


Assuntos
Síndrome de Cockayne/genética , Proteínas de Ligação a DNA/genética , Xeroderma Pigmentoso/genética , Actinas/genética , Idoso , Reparo do DNA/genética , Proteínas de Ligação a DNA/química , Anemia de Fanconi/genética , Feminino , Predisposição Genética para Doença/genética , Humanos , Lamina Tipo A/genética , Masculino , Pessoa de Meia-Idade , Linhagem
18.
J Clin Invest ; 127(10): 3598-3608, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28846075

RESUMO

The tumor suppressor p53, a master regulator of the cellular response to stress, is tightly regulated by the E3 ubiquitin ligase MDM2 via an autoregulatory feedback loop. In addition to its well-established role in tumorigenesis, p53 has also been associated with aging in mice. Several mouse models with aberrantly increased p53 activity display signs of premature aging. However, the relationship between dysfunction of the MDM2/p53 axis and human aging remains elusive. Here, we have identified an antiterminating homozygous germline mutation in MDM2 in a patient affected by a segmental progeroid syndrome. We show that this mutation abrogates MDM2 activity, thereby resulting in enhanced levels and stability of p53. Analysis of the patient's primary cells, genome-edited cells, and in vitro and in vivo analyses confirmed the MDM2 mutation's aberrant regulation of p53 activity. Functional data from a zebrafish model further demonstrated that mutant Mdm2 was unable to rescue a p53-induced apoptotic phenotype. Altogether, our findings indicate that mutant MDM2 is a likely driver of the observed segmental form of progeria.


Assuntos
Senilidade Prematura , Mutação em Linhagem Germinativa , Proteínas Proto-Oncogênicas c-mdm2 , Proteína Supressora de Tumor p53 , Proteínas de Peixe-Zebra , Peixe-Zebra , Senilidade Prematura/genética , Senilidade Prematura/metabolismo , Animais , Apoptose/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
19.
Aging (Albany NY) ; 9(4): 1143-1152, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28377537

RESUMO

Individuals suffering from Werner syndrome (WS) exhibit many clinical signs of accelerated aging. While the underlying constitutional mutation leads to accelerated rates of DNA damage, it is not yet known whether WS is also associated with an increased epigenetic age according to a DNA methylation based biomarker of aging (the "Epigenetic Clock"). Using whole blood methylation data from 18 WS cases and 18 age matched controls, we find that WS is associated with increased extrinsic epigenetic age acceleration (p=0.0072) and intrinsic epigenetic age acceleration (p=0.04), the latter of which is independent of age-related changes in the composition of peripheral blood cells. A multivariate model analysis reveals that WS is associated with an increase in DNA methylation age (on average 6.4 years, p=0.011) even after adjusting for chronological age, gender, and blood cell counts. Further, WS might be associated with a reduction in naïve CD8+ T cells (p=0.025) according to imputed measures of blood cell counts. Overall, this study shows that WS is associated with an increased epigenetic age of blood cells which is independent of changes in blood cell composition. The extent to which this alteration is a cause or effect of WS disease phenotypes remains unknown.


Assuntos
Senilidade Prematura/genética , Epigênese Genética , Síndrome de Werner/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Biomarcadores , Contagem de Células Sanguíneas , Células Sanguíneas/ultraestrutura , Linfócitos T CD8-Positivos , Dano ao DNA , Metilação de DNA , Feminino , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais
20.
Exp Gerontol ; 87(Pt B): 182-189, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27105635

RESUMO

The US pays about twice as much per capita for health care than any other developed country, yet its health metrics rank among the lowest among peer nations - for example, the US has 12.2 maternal mortality deaths per 100,000 compared to 4.8 in Canada which, like other developed nations, has a single payer health care program. The leading cause of bankruptcies in the US is attributable to medical expenses. Despite recently introduced legislation (the Affordable Care Act) many millions of Americans remain uninsured or underinsured. We shall consider views on the pathogenesis of such a dysfunctional health care system and make suggestions for how it can be improved. We shall also emphasize the importance of an integrated system of universal health care for population-based epidemiological research and preventive medicine, including its implications for the enhancement of the healthspans and lifespans of future generations via trans-generational inheritance. Finally, we suggest that the anticipated major health care savings of such a system, if partially invested in basic and translational research, should accelerate progress towards further gains in healthspans and lifespans.


Assuntos
Geriatria/economia , Geriatria/ética , Custos de Cuidados de Saúde/estatística & dados numéricos , Custos de Cuidados de Saúde/tendências , Disparidades em Assistência à Saúde/ética , Humanos , Patient Protection and Affordable Care Act/economia , Sistema de Fonte Pagadora Única , Estados Unidos
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