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1.
Biochem Biophys Res Commun ; 721: 149972, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38772213

RESUMO

Endoplasmic reticulum stress (ERS) plays a crucial role in the pathogenesis of diabetic nephropathy (DN), and it is often accompanied by an increase in reactive oxygen species (ROS) production. However, the precise relationship between NFE2-related factor-2 (Nrf2), a key regulator of ROS balance, and ERS in DN remains elusive. This study aimed to investigate the impact of Nrf2 on ERS and its therapeutic potential in DN. Herein, ERS-related changes, including increased activating transcription factor-6 (ATF6), glucose-regulated protein 78 (GRP78), and transcription factor C/EBP homologous protein (CHOP) expression, were observed in the renal tissues of streptozotocin-induced DN mice and high glucose cultured human renal proximal tubular (HK-2) cells. Nrf2 knockdown increased the sensitivity of HK-2 cells to ERS under high glucose conditions, underscoring the regulatory role of Nrf2 in ERS modulation. Notably, upregulating Nrf2 in ezetimibe-treated diabetic mice restored ERS markers and ameliorated albuminuria, glomerular hypertrophy, mesangial expansion, and tubulointerstitial fibrosis. Furthermore, the inhibition of ERS in HK-2 cells by the ROS scavenger, N-acetylcysteine, highlights the interplay between ROS and ERS. This study, for the first time, elucidates that the upregulation of Nrf2 may alleviate the negative influence of ROS-mediated ERS, presenting a promising therapeutic avenue for delaying the progression of DN. These findings suggest a potential strategy for targeting Nrf2 and ERS in developing novel therapeutic interventions for DN.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2 , Espécies Reativas de Oxigênio , Regulação para Cima , Animais , Humanos , Masculino , Camundongos , Linhagem Celular , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/tratamento farmacológico , Chaperona BiP do Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regulação para Cima/efeitos dos fármacos
2.
Am J Geriatr Psychiatry ; 32(1): 71-82, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37770350

RESUMO

OBJECTIVES: Childhood adversity and lifestyle have been associated with frailty in later life, but not much is known about factors that may explain these associations. Therefore, this study aims to investigate the association of childhood adversity with frailty, and the mediating role of unhealthy lifestyle in the association. METHODS: This lifespan analysis included 152,914 adults aged 40-69 years old from the UK Biobank. We measured childhood adversity with five items: physical neglect, emotional neglect, sexual abuse, physical abuse, and emotional abuse through online mental health survey. Frailty was measured by the frailty index; an unhealthy lifestyle score (range: 0-5) was calculated based on unhealthy body mass index, smoking, alcohol consumption, physical inactivity, and unhealthy diet at the baseline survey. Multiple logistic regression and mediation analysis were performed. RESULTS: A total of 10,078 participants (6.6%) were defined as having frailty. Participants with any childhood adversity had higher odds of frailty. For example, in the fully adjusted model, with a one-point increase in cumulative score of childhood adversity, the odds of frailty increased by 38% (odds ratio: 1.38; 95% Confidence Interval: 1.36, 1.40). Unhealthy lifestyle partially mediated the associations of childhood adversity with frailty (mediation proportion: 4.4%-7.0%). The mediation proportions were largest for physical (8.2%) and sexual (8.1%) abuse. CONCLUSIONS: Childhood adversity was positively associated with frailty, and unhealthy lifestyle partially mediated the association. This newly identified pathway highlights the potential of lifestyle intervention strategies among those who experienced childhood adversity (in particular, physical, and sexual abuse) to promote healthy aging.


Assuntos
Experiências Adversas da Infância , Maus-Tratos Infantis , Fragilidade , Humanos , Idoso , Criança , Longevidade , Fragilidade/epidemiologia , Estilo de Vida , Maus-Tratos Infantis/psicologia
3.
Regul Toxicol Pharmacol ; 146: 105542, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070762

RESUMO

Arctii Fructus is the dried ripe fruit of Arctium lappa L. (family Asteraceae) and is in the Chinese pharmacopoeia. Previous research showed that the total lignans from Arctii Fructus (TLAF) have pharmacological activities related to diabetes. This study evaluated the acute and chronic (26 weeks) toxicities associated with oral daily administration of TLAF in Sprague-Dawley (SD) rats. An acute-toxicity test showed that TLAF caused 10% mortality at 3,000 mg/kg × 2 (6-h interval), with toxic symptoms, such as dyspnea and tonic convulsions, indicating potential neurotoxicity. A chronic-toxicity study showed no mortality after administration. The no observed adverse-effect level was 1,800 mg/kg (approximately 54 times higher than the human clinical dose) for 26 weeks of TLAF oral administration in SD rats, with toxicity signs of excessive oral and nasal secretions and moist circumferential hair that recovered after TLAF discontinuation. In the toxicokinetic study, the two main components of TLAF, arctigenin plasma level was positively correlated with dose and tended to accumulate after multiple doses. At 1,800 mg/kg, arctiin plasma level increased and tended to accumulate after multiple doses. These results indicated that TLFA has relatively low toxicity and the potential for clinical treatment of diabetes.


Assuntos
Diabetes Mellitus , Medicamentos de Ervas Chinesas , Lignanas , Ratos , Humanos , Animais , Ratos Sprague-Dawley , Preparações Farmacêuticas , Diabetes Mellitus/tratamento farmacológico , Lignanas/toxicidade
4.
Ecotoxicol Environ Saf ; 277: 116351, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38653027

RESUMO

The increasing concentration of Antimony (Sb) in ecological environments has raised serious concerns about its potential biotoxicological impact. This study investigated the toxicokinetics, Global DNA Methylation (GDM), biomarker expression, and Integrated Biological Response (IBR) of Sb at different concentrations in zebrafish. The toxic mechanism of Sb exposure was simulated using molecular dynamics (MD). The results showed that significant differences effect existed (BCFk: liver > ovary > gut > brain) and uptake saturation phenomenon of Sb among zebrafish tissues. Over a 54-day exposure period, the liver emerged as the main target site for Sb-induced GDM, and the restoration was slower than in other tissues during the 54-day recovery period. Moreover, the concentration of Sb had a significant impact on the normally expression of biomarkers, with GSTM1 inhibited and MTF2, MT1, TET3, and p53 showing varying degrees of activation at different Sb concentrations. This could be attributed to Sb3+ potentially occupying the active site or tightly binding to the deep cavity of these genes. The IBR and MD results highlighted DNMT1 as the most sensitive biomarker among those assessed. This heightened sensitivity can be attributed to the stable binding of Sb3+ to DNMT1, resulting in alterations in the conformation of DNMT1's catalytic domain and inhibition of its activity. Consequently, this disruption leads to damage to the integrity of GDM. The study suggests that DNA methylation could serve as a valuable biomarker for assessing the ecotoxicological impact of Sb exposure. It contributes to a better understanding of the toxicity mechanisms in aquatic environments caused potential pollutants.


Assuntos
Antimônio , Bioacumulação , Metilação de DNA , Poluentes Químicos da Água , Peixe-Zebra , Animais , Antimônio/toxicidade , Metilação de DNA/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Biomarcadores/metabolismo , Feminino , Toxicocinética , Simulação de Dinâmica Molecular , Fígado/efeitos dos fármacos , Fígado/metabolismo
5.
Genomics ; 115(1): 110538, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36494076

RESUMO

Fusarium wilt is a typical soil-borne disease caused by Fusarium oxysporum f. sp. momordicae (FOM) in bitter gourd. In this study, by comparing sequencing data at multiple time points and considering the difference between resistant (R) and susceptible (S) varieties, differentially expressed genes were screened out. Short time-series expression miner analysis revealed the upregulated expression trend of genes, which were enriched in phenylpropanoid biosynthesis, plant-pathogen interaction, and mitogen-activated protein kinase signaling pathway. Further, observation of the microstructure revealed that the R variety may form tyloses earlier than the S variety to prevent mycelium diffusion from the xylem vessel. After Fusarium wilt infection, the enzymatic activities of superoxide dismutase, peroxidase, phenylalanine ammonia lyase, and catalaseas well as levels of superoxide anion and malondialdehyde were increased in the R variety higher than those in the S variety. This study provides a reference to elucidate the disease resistance mechanism of bitter gourd.


Assuntos
Fusarium , Momordica charantia , Momordica charantia/genética , Fusarium/genética , Lignina , Transdução de Sinais , Perfilação da Expressão Gênica
6.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-39238396

RESUMO

OBJECTIVES: To analyze the associations between factors in life course and physiological disorders in the middle-aged and elderly population of Zhoushan city of Zhejiang province, and the mediating roles of lifestyle and mental health. METHODS: A total of 1553 island residents aged ≥45 years were enrolled from the Zhejiang Metabolic Syndrome Cohort Zhoushan Liuheng Sub-cohort. The demographic information, life-course information, lifestyle, and mental health information of participants were documented, and blood samples of were collected. The status of aging was evaluated by physiological disorders calculation model developed by authors previously. The Shapley value decomposition method was used to assess the cumulative and relative contribution of multiple factors in life course to the aging. Principal component analysis and hierarchical cluster analysis were used to classify subgroups. General linear regression model was used to assess the associations between the life-course subgroups and physiological disorders. Five key factors associated with aging were finally identified. Logistic regression model, general linear regression model, and mediation analysis model were used to assess the complex associations between life-course subgroups, key factors, unhealthy lifestyle, mental health, and aging. RESULTS: Shapley value decomposition method indicated that eight types of life-course factors explained 6.63% (SE=0.0008) of the individual physiological disorders variance, with the greatest relative contribution (2.78%) from adversity experiences in adulthood. The study participants were clustered into 4 subgroups, and subgroups experiencing more adversity in adulthood and having low educational attainment or experiencing more trauma and having poorer relationships in childhood had significantly higher levels of physiological disorders. Life-course subgroups and key factors (childhood trauma and health, adversity experience in adulthood, and lower education) were positively associated with unhealthy lifestyles (ß=0.12-0.41, P<0.05). In addition, life-course subgroups and key factors (adversity experience in adulthood) were positively associated with psychological problems (OR=2.14-4.68, P<0.05). Unhealthy lifestyle scores showed a marginal significant association with physiological disorders (ß=0.03, P=0.055). However, no significant association was found between psychological problems and physiological disorders (ß=0.03, P=0.748). The results of the mediation analysis model suggested that unhealthy lifestyles partially mediated the associations between life-course subgroups, adversity experience in adulthood and physiological disorders. CONCLUSIONS: Multiple life-course factors contribute about 6% of the variance in physiological disorders in the middle aged and elderly population of the study area; subgroups with adverse life course experiences have higher levels of aging; and the association may be partially mediated by unhealthy lifestyles.

7.
BMC Med ; 21(1): 74, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829175

RESUMO

BACKGROUND: Comorbidities among cancer survivors remain a serious healthcare burden and require appropriate management. Using two widely used frailty indicators, this study aimed to evaluate whether frailty was associated with the incidence risk of cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) among long-term cancer survivors. METHODS: We included 13,388 long-term cancer survivors (diagnosed with cancer over 5 years before enrolment) free of CVD and 6101 long-term cancer survivors free of T2DM, at the time of recruitment (aged 40-69 years), from the UK Biobank. Frailty was assessed by the frailty phenotype (FP_Frailty, range: 0-5) and the frailty index (FI_Frailty, range: 0-1) at baseline. The incident CVD and T2DM were ascertained through linked hospital data and primary care data, respectively. The associations were examined using Cox proportional hazards regression models. RESULTS: Compared with non-frail participants, those with pre-frailty (FP_Frailty [met 1-2 of the components]: hazard ratio [HR]=1.18, 95% confidence interval [CI]: 1.05, 1.32; FI_Frailty [0.10< FI ≤0.21]: HR=1.51, 95% CI: 1.32, 1.74) and frailty (FP_Frailty [met ≥3 of the components]: HR=2.12, 95% CI: 1.73, 2.60; FI_Frailty [FI >0.21]: HR=2.19, 95% CI: 1.85, 2.59) had a significantly higher risk of CVD in the multivariable-adjusted model. A similar association of FI_Frailty with the risk of incident T2DM was observed. We failed to find such an association for FP_Frailty. Notably, the very early stage of frailty (1 for FP_Frailty and 0.1-0.2 for FI_Frailty) was also positively associated with the risk of CVD and T2DM (FI_Frailty only). A series of sensitivity analyses confirmed the robustness of the findings. CONCLUSIONS: Frailty, even in the very early stage, was positively associated with the incidence risk of CVD and T2DM among long-term cancer survivors, although discrepancies existed between frailty indicators. While the validation of these findings is required, they suggest that routine monitoring, prevention, and interventive programs of frailty among cancer survivors may help to prevent late comorbidities and, eventually, improve their quality of life. Especially, interventions are recommended to target those at an early stage of frailty when healthcare resources are limited.


Assuntos
Sobreviventes de Câncer , Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Fragilidade , Neoplasias , Humanos , Idoso , Fragilidade/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Doenças Cardiovasculares/epidemiologia , Incidência , Idoso Fragilizado , Estudos Prospectivos , Qualidade de Vida , Neoplasias/complicações
8.
Environ Res ; 218: 115022, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502898

RESUMO

OBJECTIVES: Whether household air pollution is associated with dementia risk remains unknown. This study examined the associations between solid fuel use for cooking and heating (the main source of household air pollution) and dementia risk. METHODS: This analysis included data on 11,352 participants (aged 45+ years) from the 2011 wave of China Health and Retirement Longitudinal Study, with follow-up to 2018. Dementia risk was assessed by a risk score using the Rotterdam Study Basic Dementia Risk Model (BDRM), which was subsequently standardized for analysis. Household fuel types of cooking and heating were categorized as solid (e.g., coal and crop residue) and clean (e.g., central heating and solar). Multivariable analyses were performed using generalized estimating equations. Moreover, we examined the joint associations of solid fuel use for cooking and heating with the BDRM score. RESULTS: After adjusting for potential confounders, we found an independent and significant association of solid (vs. clean) fuel use for cooking and heating with a higher BDRM score (e.g., ß = 0.17 for solid fuel for cooking; 95% confidence interval [CI]: 0.15-0.19). Participants who used solid (vs. clean) fuel for both cooking and heating had the highest BDRM score (ß = 0.32; 95% CI: 0.29-0.36). Subgroup analysis suggested stronger associations in participants living in rural areas. CONCLUSIONS: Solid fuel use for cooking and heating was independently associated with increased dementia risk in Chinese middle-aged and older adults, particularly among those living in rural areas. Our findings call for more efforts to facilitate universal access to clean energy for dementia prevention.


Assuntos
Poluição do Ar em Ambientes Fechados , Demência , Pessoa de Meia-Idade , Humanos , Idoso , Estudos Prospectivos , Estudos Longitudinais , Fatores de Risco , Culinária , China/epidemiologia , Demência/induzido quimicamente , Demência/epidemiologia
9.
Acc Chem Res ; 54(23): 4305-4318, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34761901

RESUMO

The introduction of N-containing moieties into feedstock molecules to build nitrogenated functional molecules has always been widely studied by the organic chemistry community. Progress in this field paves new roads to the synthesis of N-containing molecules, which are of significant importance in biological activities and play vital roles in pharmaceuticals and functional materials. Remarkable progress has been achieved in the field of transition metal-catalyzed C-N bond-forming reactions, typified by alkene hydroamination and the aza-Wacker reaction. However, the poisoning effect of electron-donating amine substrates on late transition metal catalysts presents a key impediment to these reactions, thus limiting the scope of amine substrates to electron-deficient amide derivatives. To address this problem, our group developed a palladium-aminomethyl complex with a three-membered palladacycle structure that allowed for the incorporation of electron-rich amine building blocks via C-C bond instead of C-N bond construction. This Account details the discovery of the well-defined aminomethyl cyclopalladated complex and recapitulates its applications for the catalysis of a series of aminomethylation reactions. We highlight how the understanding of the fundamental structural properties of the defined complex guided us toward tuning the reactivity of nucleophiles to initiate aminomethylation in different modes. Moreover, principles of designing and establishing further cascade reactions are also described.Aminomethyl cyclopalladated complexes can be prepared via the oxidative addition of aminals or N,O-acetals to Pd0 species. Thorough structural investigations by single-crystal X-ray diffraction analysis of the cyclopalladated complex suggest the presence of both aminomethylene-PdII (3-membered-ring) and Pd0-iminium (π-ligated) resonance forms, which indicates that both the palladium center and the methylene site are electrophilic. This is further verified by analysis of charge distribution. Two general types of reactions can be established, differing by the selective affinity of the nucleophiles to the two electrophilic positions, which is relevant to the "hardness suitability" of the nucleophiles with each electrophilic site. Softer nucleophiles such as alkenes prefer to attack the palladium center to initiate the reaction, mainly via migratory insertion into the Pd-C bond on the 3-membered ring with high strain. Through tandem ß-hydride or reductive elimination, the Heck-type aminomethylation of styrenes, the aminomethylalkoxylation of electron-rich olefins, and even the aminomethylamination of allenes, dienes, enynes, and carbenoids with full atom-economy have been realized in line with this reaction mode. In contrast, harder nucleophiles tend to attack the harder electrophilic methylene site, leading to the aminomethylation of electron-deficient dienes. For secondary amines, a "C-N bond metathesis" process would be furnished through a reductive elimination, 1,3-proton transfer, and oxidative addition sequence. More intriguingly, when using appropriate "dinucleophile" substrates such as electron-rich amine-tethered dienes, sequential C-N bond metathesis and intramolecular insertion would occur to furnish Pd-catalyzed annulation reactions, which exhibits both the hard and soft nucleophile reactivities mentioned above. These transformations provide convenient methods for the preparation of N-containing molecules, such as amines, diamines, amino acetals, and multiple types of N-heterocycles.

10.
J Exp Bot ; 73(3): 886-902, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34486649

RESUMO

The high accumulation of phloridzin makes apple (Malus domestica) unique in the plant kingdom, which suggests a vital role of its biosynthesis in physiological processes. In our previous study, silencing MdUGT88F1 (a key UDP-GLUCOSE: PHLORETIN 2'-O-GLUCOSYLTRANSFERASE gene) revealed the importance of phloridzin biosynthesis in apple development and Valsa canker resistance. Here, results from MdUGT88F1-silenced lines showed that phloridzin biosynthesis was indispensable for normal chloroplast development and photosynthetic carbon fixation by maintaining MdGLK1/2 (GOLDEN2-like1/2) expression. Interestingly, increased phloridzin biosynthesis did not affect plant (or chloroplast) development, but reduced nitrogen accumulation, leading to chlorophyll deficiency, light sensitivity, and sugar accumulation in MdUGT88F1-overexpressing apple lines. Further analysis revealed that MdUGT88F1-mediated phloridzin biosynthesis negatively regulated the cytosolic glutamine synthetase1-asparagine synthetase-asparaginase (GS1-AS-ASPG) pathway of ammonium assimilation and limited chlorophyll synthesis in apple shoots. The interference of phloridzin biosynthesis in the GS1-AS-ASPG pathway was also assumed to be associated with its limitation of the carbon skeleton of ammonium assimilation through metabolic competition with the tricarboxylic acid cycle. Taken together, our findings shed light on the role of MdUGT88F1-mediated phloridzin biosynthesis in the coordination between carbon and nitrogen accumulation in apple trees.


Assuntos
Ascomicetos , Malus , Carbono/metabolismo , Malus/metabolismo , Nitrogênio/metabolismo , Florizina/metabolismo
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