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1.
Mol Cell ; 80(5): 779-795.e10, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33207181

RESUMO

Protein aggregates disrupt cellular homeostasis, causing toxicity linked to neurodegeneration. Selective autophagic elimination of aggregates is critical to protein quality control, but how aggregates are selectively targeted for degradation is unclear. We compared the requirements for autophagy receptor proteins: OPTN, NBR1, p62, NDP52, and TAX1BP1 in clearance of proteotoxic aggregates. Endogenous TAX1BP1 is recruited to and required for the clearance of stress-induced aggregates, whereas ectopic expression of TAX1BP1 increases clearance through autophagy, promoting viability of human induced pluripotent stem cell-derived neurons. In contrast, TAX1BP1 depletion sensitizes cells to several forms of aggregate-induced proteotoxicity. Furthermore, TAX1BP1 is more specifically expressed in the brain compared to other autophagy receptor proteins. In vivo, loss of TAX1BP1 results in accumulation of high molecular weight ubiquitin conjugates and premature lipofuscin accumulation in brains of young TAX1BP1 knockout mice. TAX1BP1 mediates clearance of a broad range of cytotoxic proteins indicating therapeutic potential in neurodegenerative diseases.


Assuntos
Proteínas Reguladoras de Apoptose/deficiência , Autofagia , Encéfalo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Proteínas de Neoplasias/deficiência , Doenças Neurodegenerativas/metabolismo , Agregação Patológica de Proteínas/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Encéfalo/patologia , Feminino , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipofuscina/genética , Lipofuscina/metabolismo , Masculino , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/metabolismo , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/patologia , Ratos , Ratos Sprague-Dawley , Ubiquitina/genética , Ubiquitina/metabolismo
3.
Circ Res ; 131(2): 168-183, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35642564

RESUMO

BACKGROUND: Insulin resistance (IR) can increase atherosclerotic and cardiovascular risk by inducing endothelial dysfunction, decreasing nitric oxide (NO) production, and accelerating arterial inflammation. The aim is to determine the mechanism by which insulin action and NO production in endothelial cells can improve systemic bioenergetics and decrease atherosclerosis via differentiation of perivascular progenitor cells (PPCs) into brown adipocytes (BAT). METHODS: Studies used various endothelial transgenic and deletion mutant ApoE-/- mice of insulin receptors, eNOS (endothelial NO synthase) and ETBR (endothelin receptor type B) receptors for assessments of atherosclerosis. Cells were isolated from perivascular fat and micro-vessels for studies on differentiation and signaling mechanisms in responses to NO, insulin, and lipokines from BAT. RESULTS: Enhancing insulin's actions on endothelial cells and NO production in ECIRS1 transgenic mice reduced body weight and increased systemic energy expenditure and BAT mass and activity by inducing differentiation of PPCs into beige/BAT even with high-fat diet. However, positive changes in bioenergetics, BAT differentiation from PPCs and weight loss were inhibited by N(gamma)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of eNOS, in ECIRS1 mice and eNOSKO mice. The mechanism mediating NO's action on PPC differentiation into BAT was identified as the activation of solubilized guanylate cyclase/PKGIα (cGMP protein-dependent kinase Iα)/GSK3ß (glycogen synthase kinase 3ß) pathways. Plasma lipidomics from ECIRS1 mice with NO-induced increased BAT mass revealed elevated 12,13-diHOME production. Infusion of 12,13-diHOME improved endothelial dysfunction and decreased atherosclerosis, whereas its reduction had opposite effects in ApoE-/-mice. CONCLUSIONS: Activation of eNOS and endothelial cells by insulin enhanced the differentiation of PPC to BAT and its lipokines and improved systemic bioenergetics and atherosclerosis, suggesting that endothelial dysfunction is a major contributor of energy disequilibrium in obesity.


Assuntos
Tecido Adiposo Marrom , Aterosclerose , Tecido Adiposo Marrom/metabolismo , Animais , Apolipoproteínas E/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/prevenção & controle , Células Endoteliais/metabolismo , Insulina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo
4.
Cardiovasc Diabetol ; 22(1): 131, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365586

RESUMO

BACKGROUND: Impaired kidney function and albuminuria are associated with increased risk of heart failure (HF) in patients with type 2 diabetes (T2D). We investigated whether rapid kidney function decline over time is an additional determinant of increased HF risk in patients with T2D, independent of baseline kidney function, albuminuria, and other HF predictors. METHODS: Included in the study were 7,539 participants in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study with baseline urinary albumin-to-creatinine ratio (UACR) data, who had completed 4 years of follow-up and had ≥ 3 eGFR measurements during that period (median eGFR/year = 1.9, IQR 1.7-3.2). The association between rapid kidney function decline (eGFR loss ≥ 5 ml/min/1.73 m2/year) and odds of HF hospitalization or HF death during the first 4 years of follow-up was estimated by logistic regression. The improvement in risk discrimination provided by adding rapid kidney function decline to other HF risk factors was evaluated as the increment in the area under the Receiving Operating Characteristics curve (ROC AUC) and integrated discrimination improvement (IDI). RESULTS: Over 4 years of follow-up, 1,573 participants (20.9%) experienced rapid kidney function decline and 255 (3.4%) experienced a HF event. Rapid kidney function decline was associated with a ~ 3.2-fold increase in HF odds (3.23, 95% CI, 2.51-4.16, p < 0.0001), independent of baseline CVD history. This estimate was not attenuated by adjustment for potential confounders, including eGFR and UACR at baseline as well as at censoring (3.74; 95% CI 2.63-5.31). Adding rapid kidney function decline during follow-up to other clinical predictors (WATCH-DM score, eGFR, and UACR at study entry and end of follow-up) improved HF risk classification (ROC AUC = + 0.02, p = 0.027; relative IDI = + 38%, p < 0.0001). CONCLUSIONS: In patients with T2D, rapid kidney function decline is associated with a marked increase in HF risk, independent of starting kidney function and/or albuminuria. These findings highlight the importance of serial eGFR measurements over time to improve HF risk estimation in T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Albuminúria , Taxa de Filtração Glomerular , Rim , Fatores de Risco de Doenças Cardíacas
5.
J Cell Biochem ; 121(2): 1050-1060, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31452252

RESUMO

Oral cancer is a major public health concern in the Asian countries predominated by India which accounts for 33.81% of the annual global oral cancer burden. The well-established high-risk factors associated with oral cancer include tobacco, areca nut, alcohol consumption, and high-risk human papilloma virus types 16/18. Additionally, in the past two decades, the critical role of the genomic constitution of individuals in oral cancer susceptibility has emerged. Accumulating evidence indicates the association of several single nucleotide polymorphisms (SNPs) with oral cancer risk. Thus in the current study, we assessed the association of thirteen SNPs in seven transcription factor genes along with HBB (a control SNP) to identify high-risk genotypes associated with increased oral cancer risk in an Indian cohort of tobacco habitués. Fourteen SNPs were investigated in 500 patients with oral cancer and 500 clinically healthy long-term tobacco users as controls of Indian ethnicity. Allelic discrimination real-time polymerase chain reaction was the method of choice for genotyping the samples. Logistic regression analysis was performed and the association of SNPs with oral cancer risk was estimated using odds ratio (OR) and 95% confidence interval (CI). We observed five SNPs-rs2051526 (ETV6), rs6021247 (NFATC2), rs3757769 (SND1), rs7085532 (TCF7L2), and rs7778413 (SND1) indicating increased oral cancer risk with OR ranging from 1.61 to 34.60. Further, as a proof of concept, the coinheritance of high-risk genotypes in rs6021247 (NFATC2) GG (OR, 2.77; CI, 2.09-3.69) and rs7778413 (SND1) CC (OR, 34.60; CI, 17.32-69.13) reflected further increase in the risk with OR-49.94 (CI, 16.25-153.48). The present study indicates the association of transcription factor SNPs with increased oral cancer risk constituting "predictive biomarkers" in oral cancers.


Assuntos
Predisposição Genética para Doença , Neoplasias Bucais/epidemiologia , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Índia/epidemiologia , Masculino , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Fatores de Risco
6.
Int J Obes (Lond) ; 44(3): 568-578, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31740726

RESUMO

BACKGROUND: High body mass index (BMI) is associated with neurocognitive impairments that contribute to overeating and interfere with weight loss efforts. Overweight and obesity at midlife can accelerate neurodegenerative changes and increase the risk of late-life dementia. Noninvasive neuromodulation represents a novel, affordable and scalable approach to improve neurocognitive function in this context. The purpose of this proof-of-concept study was to examine whether transcranial direct current stimulation (tDCS) aimed at enhancing prefrontal cortex activity could enhance weight loss, in combination with a hypocaloric diet, and study underlying mechanisms. METHODS: Overall, 38 women with BMI 25-35 kg/m2 underwent a 4 week randomized, double-blinded, sham-controlled, and parallel-design intervention, during which they received eight sessions of tDCS (n = 18 sham, n = 20 active) in combination with a diet (caloric goal of 20 kcal/kg/day). We evaluated longitudinal changes in body weight, appetite and food craving. In addition, we examined the contribution of cognitive-executive processes via food-modified computerized tasks. RESULTS: We found that the active group had more reduction in body weight than the sham group throughout the study (p = 0.020) and significant weekly weight loss. At 4 weeks, the active group lost 2.32% of initial body weight (sham: 1.29%). Components of subjective appetite and food craving showed a trend toward more reduction in the active group. These changes were paralleled by significant improvements in task performance in the active group, particularly in a dual task that required inhibitory control and working memory (p = 0.007-0.031). Improvement in inhibitory control performance predicted reduction in lack of control overeating, explaining 43.5% of its variance at the end of the study (p = 0.003). No significant adverse effects were observed. CONCLUSIONS: Our results provide proof-of-concept validation of prefrontal-targeted tDCS, combined with a diet, in midlife women with excess body weight, paving the way for larger studies evaluating clinical efficacy and long-term effects of this intervention.


Assuntos
Dieta Redutora , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua , Redução de Peso/fisiologia , Idoso , Apetite/fisiologia , Fissura/fisiologia , Comportamento Alimentar/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/terapia , Estudo de Prova de Conceito
7.
J Cell Biochem ; 120(4): 5519-5530, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30367521

RESUMO

H-Ras oncogene plays a critical role in the transformation of normal cells to a malignant phenotype through constitutive activation of the GTP bound protein leading to uncontrolled cell proliferation in several human cancers. Thus, H-Ras oncoprotein serves as an excellent target for anticancer drug discovery. To identify novel H-Ras inhibitors, we performed structure-based virtual screening of the Maybridge HitFinder™ library using Schrodinger suite. Thirty ligands from the chemical library were identified as they showed preferential in silico binding initially to H-Ras proteins with Gly12Val, Gly13Asp, and Gly12Val-Gly13Asp mutations. Absorption, distribution, metabolism, excretion, and toxicity profile confirmed drug-like properties of the compounds. Three representative molecules were tested for antiproliferative effect on T24 urinary bladder carcinoma cell line, MCF-7 breast cancer cell line and HDF-7 normal dermal fibroblast cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Two compounds (Cmpds) showed antiproliferative activity exclusively in the cancer cell lines with minimal effect on the control HDF-7 cells. The effect of compound treatment on cell cycle progression, assessed by propidium iodide (PI) staining, depicted increased arrest of T24 cell line in the sub G1 phase. Further, Annexin-V PI dual staining and pan caspase inhibitor Z-VAD-fmk indicated caspase-dependent apoptotic activity of Cmpds 1 and 3. Our findings demonstrate caspase-dependent apoptotic activity of Cmpds 1 and 3 selectively against Gly12Val mutated T24 cancer cell line implicating a potential for treatment of bladder cancer. We envisage that these molecules may be promising candidates with potential therapeutic value in H-Ras mutation-associated cancers.


Assuntos
Antineoplásicos , Caspase 1/metabolismo , Caspase 3/metabolismo , Simulação por Computador , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Antineoplásicos/química , Antineoplásicos/farmacologia , Humanos , Células MCF-7 , Neoplasias/epidemiologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
9.
N Engl J Med ; 375(23): 2304-2305, 2016 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-28112899
10.
J Clin Endocrinol Metab ; 109(8): 2124-2135, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38262002

RESUMO

BACKGROUND: The role of glycemic control and its variability on the rate of kidney function decline after the onset of diabetic kidney disease (DKD) remains unclear. METHODS: The association between baseline glycated hemoglobin (HbA1c) and rates of estimated glomerular filtration rate (eGFR) loss during follow-up was examined by mixed-effects linear regression in 530 individuals with type 1 diabetes and early-to-moderate DKD from the Preventing Early Renal Loss (PERL) trial and 2378 individuals with type 2 diabetes and established DKD from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. The benefit of intensive vs standard glycemic control in slowing eGFR decline was examined in ACCORD. The associations between continuous glucose monitoring-derived short-term glycemic variability indices and rate of eGFR decline were also evaluated in PERL. RESULTS: A higher baseline HbA1c was associated with a more negative eGFR slope in both PERL and ACCORD (-0.87 and -0.27 mL/min/1.73 m2/year per Hba1c unit increment, P < .0001 and P = .0002, respectively). In both studies, the strength of this association progressively increased with increasing levels of albuminuria (P for interaction <.05). Consistent with this, the benefit of intensive glycemic control on eGFR decline was greater in ACCORD participants with severe rather than moderate albuminuria (+1.13 vs + 0.26 mL/min/1.73 m2/year, P = .01). No independent associations were found in PERL between short-term glycemic variability indices and rate of eGFR decline. CONCLUSION: In both type 1 and type 2 diabetes, poor glycemic control is associated with a more rapid rate of glomerular filtration rate decline after DKD onset, especially in persons with severe albuminuria.

11.
Diabetes ; 73(5): 751-762, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37467433

RESUMO

Results of previous studies have suggested that cardiovascular autonomic neuropathy (CAN) may predict rapid kidney function decline among people with diabetes. We analyzed the association between baseline CAN and subsequent glomerular filtration rate (GFR) decline among individuals with type 1 diabetes (T1D) from the Preventing Early Renal Loss in Diabetes (PERL) study (N = 469) and with type 2 diabetes (T2D) from Action to Control Cardiovascular Risk in Diabetes (ACCORD) (N = 7,973). Baseline CAN was ascertained with electrocardiogram-derived heart rate variability indices. Its association with GFR slopes, rapid kidney function decline (GFR loss of ≥5 mL/min/1.73 m2/year), and ≥40% GFR loss was evaluated by linear mixed-effects, logistic, and Cox regression, respectively. Participants with CAN experienced more rapid GFR decline, by an excess 1.15 mL/min/1.73 m2/year (95% CI -1.93 to -0.37; P = 4.0 × 10-3) in PERL and 0.34 mL/min/1.73 m2/year (95% CI -0.49 to -0.19; P = 6.3 × 10-6) in ACCORD. This translated to 2.11 (95% CI 1.23-3.63; P = 6.9 × 10-3) and 1.39 (95% CI 1.20-1.61; P = 1.1 × 10-5) odds ratios of rapid kidney function decline in PERL and ACCORD, respectively. Baseline CAN was also associated with a greater risk of ≥40% GFR loss events during follow-up (hazard ratio 2.60 [95% CI 1.15-5.45], P = 0.02, in PERL and hazard ratio 1.54 [95% CI 1.28-1.84], P = 3.8 × 10-6, in ACCORD). These associations remained significant after adjustment for potential confounders, including baseline GFR and albuminuria. Our findings indicate that CAN is a strong, independent predictor of rapid kidney function decline in both T1D and T2D. Further studies of the link between these two complications may help with development of new therapies to prevent kidney function decline in patients with diabetes.

12.
Nephrol Dial Transplant ; 27(12): 4411-3, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22622453

RESUMO

BACKGROUND: We investigated whether the coronary artery disease (CAD) locus on chromosome 9p21 (as represented by single nucleotide polymorphism rs2383206) is associated with low estimated glomerular filtration rate (eGFR) or increased urinary albumin excretion in patients with Type 2 diabetes mellitus (T2DM). METHODS: Four samples, including a total of 3167 patients, were studied. The presence of low eGFR (<60 mL/min/1.73m(2)) was estimated from serum creatinine by means of the Modification of Diet in Renal Disease Study equation. Increased urinary albumin excretion was defined as an albumin-creatinine ratio (ACR) ≥2.5 mg/mmol in men and ≥3.5 mg/mmol in women. RESULTS: No association was found between rs2383206 and low eGFR or increased ACR in each sample as well as in a pooled analysis (overall odds ratio = 1.07, 95% confidence interval 0.94-1.22, P = 0.31 and overall odds ratio = 1.00, 95% confidence interval 0.90-1.12, P = 0.95, respectively). No interaction was observed between rs2383206 and poor glycemic control [HbA1c was above the median in the pooled sample (7.7%) in modulating eGFR or ACR (P for interaction = 0.42 and 0.90, respectively)]. CONCLUSION: Variability at the 9p21 CAD locus is unlikely to play a role in modulating susceptibility to kidney dysfunction in patients with T2DM.


Assuntos
Albuminúria/genética , Cromossomos Humanos Par 9/genética , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/genética , Angiopatias Diabéticas/fisiopatologia , Taxa de Filtração Glomerular/genética , Rim/fisiopatologia , Feminino , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
13.
J Biomol Struct Dyn ; 40(6): 2407-2416, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33111621

RESUMO

The p53 gene is mutated in greater than 50% of several human cancers including bladder urothelial carcinoma, lung adenocarcinoma, colorectal carcinoma, and oral cancer. Mutations in the p53 gene occur predominantly in the DNA-binding domain causing loss of function and accumulation of dysfunctional p53 protein in tumors by hetero-oligomerization with the wild type p53. Thus an in silico approach for the rational design of potent, pharmacologically active small drug-like compounds targeting mutated p53 was undertaken. Molecular dynamics simulations of the wild type p53 monomer and p53 mutants R175H and R248Q were performed using Discovery Studio v3.5. Phase was used to generate pharmacophore models and the sitemap generated pocket was used to screen the Maybridge HitFinderTM library using Schrodinger Suite. We identified ten compounds (Cmpd-1 to Cmpd-10) that showed preferential binding to p53 mutants, and their pharmacokinetic profiles complied with the ADMET rules. Cmpd-4 and Cmpd-8 demonstrated binding with mutated p53 at cysteine 124, similar to the mutant p53 reactivating compound APR-246 (PRIMA-1Met) for functional restoration of the mutant p53. We propose the identified compounds as suitable drug candidates against mutated p53 protein, with the specific small drug-like molecules as either single drugs or in combination with lower doses of additional cytotoxic drugs, consequently reducing adverse side effects in patients.Communicated by Ramaswamy H. Sarma.


Assuntos
Antineoplásicos , Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Feminino , Humanos , Masculino , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico
14.
Geroscience ; 44(1): 415-427, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34773197

RESUMO

Chronological age (CA) is determined by time of birth, whereas biological age (BA) is based on changes on a cellular level and strongly correlates with morbidity, mortality, and longevity. Type 2 diabetes (T2D) associates with increased morbidity and mortality; thus, we hypothesized that BA would be increased and calculated it from biomarkers collected at routine clinical visits. Deidentified data was obtained from three cohorts of patients (20-80 years old)-T2D, type 1 diabetes (T1D), and prediabetes-and compared to gender- and age-matched non-diabetics. Eight clinical biomarkers that correlated with CA in people without diabetes were used to calculate BA using the Klemera and Doubal method 1 (KDM1) and multiple linear regression (MLR). The phenotypic age (PhAge) formula was used with its predetermined biomarkers. BA of people with T2D was, on average, 12.02 years higher than people without diabetes (p < 0.0001), while BA in T1D was 16.32 years higher (p < 0.0001). Results were corroborated using MLR and PhAge. The biomarkers with the strongest correlation to increased BA in T2D using KDM were A1c (R2 = 0.23, p < 0.0001) and systolic blood pressure (R2 = 0.21, p < 0.0001). BMI had a positive correlation to BA in non-diabetes subjects but disappeared in those with diabetes. Mortality data using the ACCORD trial was used to validate our results and showed a significant correlation between higher BA and decreased survival. In conclusion, BA is increased in people with diabetes, irrespective of pathophysiology, and to a lesser extent in prediabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Humanos , Longevidade , Pessoa de Meia-Idade , Análise Multivariada , Adulto Jovem
15.
Diabetes Care ; 45(8): 1882-1892, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35696261

RESUMO

OBJECTIVE: To identify novel biomarkers of cardiovascular disease (CVD) risk in type 2 diabetes (T2D) via a hypothesis-free global metabolomics study, while taking into account renal function, an important confounder often overlooked in previous metabolomics studies of CVD. RESEARCH DESIGN AND METHODS: We conducted a global serum metabolomics analysis using the Metabolon platform in a discovery set from the Joslin Kidney Study having a nested case-control design comprising 409 individuals with T2D. Logistic regression was applied to evaluate the association between incident CVD events and each of the 671 metabolites detected by the Metabolon platform, before and after adjustment for renal function and other CVD risk factors. Significant metabolites were followed up with absolute quantification assays in a validation set from the Joslin Heart Study including 599 individuals with T2D with and without clinical evidence of significant coronary heart disease (CHD). RESULTS: In the discovery set, serum orotidine and 2-piperidinone were significantly associated with increased odds of incident CVD after adjustment for glomerular filtration rate (GFR) (odds ratio [OR] per SD increment 1.94 [95% CI 1.39-2.72], P = 0.0001, and 1.62 [1.26-2.08], P = 0.0001, respectively). Orotidine was also associated with increased odds of CHD in the validation set (OR 1.39 [1.11-1.75]), while 2-piperidinone did not replicate. Furthermore, orotidine, being inversely associated with GFR, mediated 60% of the effects of declining renal function on CVD risk. Addition of orotidine to established clinical predictors improved (P < 0.05) C statistics and discrimination indices for CVD risk (ΔAUC 0.053, rIDI 0.48, NRI 0.42) compared with the clinical predictors alone. CONCLUSIONS: Through a robust metabolomics approach, with independent validation, we have discovered serum orotidine as a novel biomarker of increased odds of CVD in T2D, independent of renal function. Additionally, orotidine may be a biological mediator of the increased CVD risk associated with poor kidney function and may help improve CVD risk prediction in T2D.


Assuntos
Doenças Cardiovasculares , Doença das Coronárias , Diabetes Mellitus Tipo 2 , Biomarcadores , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Humanos , Metabolômica , Estudos Prospectivos , Fatores de Risco , Uridina/análogos & derivados
16.
J Clin Endocrinol Metab ; 106(4): 1139-1149, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33378459

RESUMO

CONTEXT: Cognitive dysfunction is a growing and understudied public health issue in the aging type 1 diabetic population and is difficult and time-consuming to diagnose. Studies in long duration type 1 diabetes have reported the presence of proliferative diabetic retinopathy was associated with cognitive dysfunction. OBJECTIVE: This study assessed whether structural and vascular abnormalities of the retina, representing an extension of the central nervous system, are associated with cognitive impairment and other complications of type 1 diabetes. METHODS: An observational cross-sectional study of individuals with 50 or more years of type 1 diabetes (Joslin Medalist Study) was conducted at a university hospital in the United States. The study included 129 participants with complete cognitive testing. Validated cognitive testing measures included psychomotor speed, and immediate, and delayed memory. Optical coherence tomography (OCT) and OCT angiography (OCTA) were performed to obtain neural retinal layer thicknesses and vascular density for superficial (SCP) and deep retinal capillary plexus (DCP). Multivariable modeling was adjusted for potential confounders associated with outcomes in unadjusted analyses. RESULTS: Decreased vessel density of the SCP and DCP was associated with worse delayed memory (DCP: P = .002) and dominant hand psychomotor speed (SCP: P = .01). Thinning of the retinal outer nuclear layer was associated with worse psychomotor speed both in nondominant and dominant hands (P = .01 and P = .05, respectively). Outer plexiform layer thickness was associated with delayed memory (P = .04). CONCLUSION: These findings suggest that noninvasive retinal imaging using OCT and OCTA may assist in estimating the risks for cognitive dysfunction in people with type 1 diabetes.


Assuntos
Cognição/fisiologia , Diabetes Mellitus Tipo 1/patologia , Neurônios Retinianos/patologia , Vasos Retinianos/patologia , Idoso , Angiografia/métodos , Capilares/diagnóstico por imagem , Capilares/patologia , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/psicologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/patologia , Retinopatia Diabética/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/diagnóstico por imagem , Retina/patologia , Vasos Retinianos/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Estados Unidos
17.
J Cell Biol ; 220(5)2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33891012

RESUMO

The VPS13 gene family consists of VPS13A-D in mammals. Although all four genes have been linked to human diseases, their cellular functions are poorly understood, particularly those of VPS13D. We generated and characterized knockouts of each VPS13 gene in HeLa cells. Among the individual knockouts, only VPS13D-KO cells exhibit abnormal mitochondrial morphology. Additionally, VPS13D loss leads to either partial or complete peroxisome loss in several transformed cell lines and in fibroblasts derived from a VPS13D mutation-carrying patient with recessive spinocerebellar ataxia. Our data show that VPS13D regulates peroxisome biogenesis.


Assuntos
Peroxissomos/genética , Peroxissomos/metabolismo , Proteínas/genética , Proteínas/metabolismo , Células HEK293 , Células HeLa , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mutação/genética
18.
Diabetes Care ; 44(1): 164-173, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33144354

RESUMO

OBJECTIVE: The effects of preventive interventions on cardiovascular autonomic neuropathy (CAN) remain unclear. We examined the effect of intensively treating traditional risk factors for CAN, including hyperglycemia, hypertension, and dyslipidemia, in individuals with type 2 diabetes (T2D) and high cardiovascular risk participating in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. RESEARCH DESIGN AND METHODS: CAN was defined as heart rate variability indices below the fifth percentile of the normal distribution. Of 10,251 ACCORD participants, 71% (n = 7,275) had a CAN evaluation at study entry and at least once after randomization. The effects of intensive interventions on CAN were analyzed among these subjects through generalized linear mixed models. RESULTS: As compared with standard intervention, intensive glucose treatment reduced CAN risk by 16% (odds ratio [OR] 0.84, 95% CI 0.75-0.94, P = 0.003)-an effect driven by individuals without cardiovascular disease (CVD) at baseline (OR 0.73, 95% CI 0.63-0.85, P < 0.0001) rather than those with CVD (OR 1.10, 95% CI 0.91-1.34, P = 0.34) (P interaction = 0.001). Intensive blood pressure (BP) intervention decreased CAN risk by 25% (OR 0.75, 95% CI 0.63-0.89, P = 0.001), especially in patients ≥65 years old (OR 0.66, 95% CI 0.49-0.88, P = 0.005) (P interaction = 0.05). Fenofibrate did not have a significant effect on CAN (OR 0.91, 95% CI 0.78-1.07, P = 0.26). CONCLUSIONS: These data confirm a beneficial effect of intensive glycemic therapy and demonstrate, for the first time, a similar benefit of intensive BP control on CAN in T2D. A negative CVD history identifies T2D patients who especially benefit from intensive glycemic control for CAN prevention.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Fenofibrato , Idoso , Glicemia , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Humanos , Fatores de Risco
19.
Diabetes Care ; 44(6): 1410-1418, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33863751

RESUMO

OBJECTIVE: Current type 2 diabetes (T2D) management contraindicates intensive glycemia treatment in patients with high cardiovascular disease (CVD) risk and is partially motivated by evidence of harms in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. Heterogeneity in response to intensive glycemia treatment has been observed, suggesting potential benefit for some individuals. RESEARCH DESIGN AND METHODS: ACCORD was a randomized controlled trial that investigated whether intensively treating glycemia in individuals with T2D would reduce CVD outcomes. Using a novel approach to cluster HbA1c trajectories, we identified groups in the intensive glycemia arm with modified CVD risk. Genome-wide analysis and polygenic score (PS) were developed to predict group membership. Mendelian randomization was performed to infer causality. RESULTS: We identified four clinical groupings in the intensive glycemia arm, and clinical group 4 (C4) displayed fewer CVD (hazard ratio [HR] 0.34; P = 2.01 × 10-3) and microvascular outcomes (HR 0.86; P = 0.015) than those receiving standard treatment. A single-nucleotide polymorphism, rs220721, in MAS1 reached suggestive significance in C4 (P = 4.34 × 10-7). PS predicted C4 with high accuracy (area under the receiver operating characteristic curve 0.98), and this predicted C4 displayed reduced CVD risk with intensive versus standard glycemia treatment (HR 0.53; P = 4.02 × 10-6), but not reduced risk of microvascular outcomes (P < 0.05). Mendelian randomization indicated causality between PS, on-trial HbA1c, and reduction in CVD outcomes (P < 0.05). CONCLUSIONS: We found evidence of a T2D clinical group in ACCORD that benefited from intensive glycemia treatment, and membership in this group could be predicted using genetic variants. This study generates new hypotheses with implications for precision medicine in T2D and represents an important development in this landmark clinical trial warranting further investigation.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Glicemia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/genética , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/genética , Comportamentos Relacionados com a Saúde , Humanos , Modelos de Riscos Proporcionais , Proto-Oncogene Mas , Fatores de Risco
20.
Diabetes ; 69(10): 2206-2216, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651240

RESUMO

A chromosome 1q25 variant (rs10911021) has been associated with coronary heart disease (CHD) in type 2 diabetes. In human umbilical vein endothelial cells (HUVECs), the risk allele "C" is associated with lower expression of the adjacent gene GLUL encoding glutamine synthase, converting glutamic acid to glutamine. To further investigate the mechanisms through which this locus affects CHD risk, we measured 35 intracellular metabolites involved in glutamic acid metabolism and the γ-glutamyl cycle in 62 HUVEC strains carrying different rs10911021 genotypes. Eight metabolites were positively associated with the risk allele (17-58% increase/allele copy, P = 0.046-0.002), including five γ-glutamyl amino acids, ß-citryl-glutamate, N-acetyl-aspartyl-glutamate, and ophthalmate-a marker of γ-glutamyl cycle malfunction. Consistent with these findings, the risk allele was also associated with decreased glutathione-to-glutamate ratio (-9%, P = 0.012), decreased S-lactoylglutathione (-41%, P = 0.019), and reduced detoxification of the atherogenic compound methylglyoxal (+54%, P = 0.008). GLUL downregulation by shRNA caused a 40% increase in the methylglyoxal level, which was completely prevented by glutamine supplementation. In summary, we have identified intracellular metabolic traits associated with the 1q25 risk allele in HUVECs, including impairments of the γ-glutamyl cycle and methylglyoxal detoxification. Glutamine supplementation abolishes the latter abnormality, suggesting that such treatment may prevent CHD in 1q25 risk allele carriers.


Assuntos
Doença das Coronárias/metabolismo , Células Endoteliais/metabolismo , Cromossomos Humanos Par 1/metabolismo , Doença das Coronárias/genética , Dipeptídeos , Endoftalmite/metabolismo , Glutamato-Amônia Ligase/metabolismo , Glutamatos/metabolismo , Glutamina/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Aldeído Pirúvico/metabolismo , RNA Interferente Pequeno/metabolismo
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