RESUMO
Biothiols, including glutathione (GSH), homocysteine (Hcy) and cysteine (Cys), play crucial roles in various physiological processes. Though an array of fluorescent probes have been designed to visualize biothiols in living organisms, few one-for-all imaging agents for sensing biothiols with fluorescence and photoacoustic imaging capabilities have been reported, since instructions for synchronously enabling and balancing every optical imaging efficacy are deficient. Herein, a new near-infrared thioxanthene-hemicyanine dye (Cy-DNBS) has been constructed for fluorescence and photoacoustic imaging of biothiols in vitro and in vivo. Upon treatment with biothiols, the absorption peak of Cy-DNBS shifted from 592 nm to 726 nm, resulting in a strong NIR absorption as well as a subsequent turn-on PA signal. Meanwhile, the fluorescence intensity increased instantaneously at 762 nm. Then, Cy-DNBS was successfully utilized for imaging endogenous and exogenous biothiols in HepG2 cells and mice. In particular, Cy-DNBS was employed for tracking biothiols upregulation in the liver of mice triggered by S-adenosyl methionine by means of fluorescent and photoacoustic imaging methods. We expect that Cy-DNBS serves as an appealing candidate for deciphering biothiols-related physiological and pathological processes.
Assuntos
Cisteína , Neoplasias , Animais , Camundongos , Corantes Fluorescentes , Espectrometria de Fluorescência , Imagem Óptica/métodos , Fígado , Glutationa , HomocisteínaRESUMO
Sites and mechanisms regulating the supply of homocysteine (Hcy) to the circulation are unexplored in humans. We studied the exchange of Hcy across the forearm in CKD patients (n = 17, eGFR 20 ± 2 ml/min), in hemodialysis (HD)-treated patients (n = 14) and controls (n = 9). Arterial Hcy was ~ 2.5 folds increased in CKD and HD patients (p < 0.05-0.03 vs. controls). Both in controls and in patients Hcy levels in the deep forearm vein were consistently greater (+~7%, p < 0.05-0.01) than the corresponding arterial levels, indicating the occurrence of Hcy release from muscle. The release of Hcy from the forearm was similar among groups. In all groups arterial Hcy varied with its release from muscle (p < 0.03-0.02), suggesting that muscle plays an important role on plasma Hcy levels. Forearm Hcy release was inversely related to folate plasma level in all study groups but neither to vitamin B12 and IL-6 levels nor to muscle protein net balance. These data indicate that the release of Hcy from peripheral tissue metabolism plays a major role in influencing its Hcy plasma levels in humans and patients with CKD, and that folate is a major determinant of Hcy release.
Assuntos
Insuficiência Renal Crônica , Humanos , Insuficiência Renal Crônica/terapia , Diálise Renal , Ácido Fólico , Vitamina B 12 , Músculo Esquelético , HomocisteínaRESUMO
BACKGROUND: Alzheimer's disease (AD) is the most common form of dementia. In this study, serum levels of autophagy-related 5 (ATG5), apolipoprotein B-48, thyroid hormones, and homocysteine were examined in patients with AD to determine their diagnostic and predictive value for early diagnosis and prevention of AD. MATERIALS: For this study, fifty serum samples were obtained from patients with AD and fifty serum samples from healthy controls. Serum levels of ATG 5, apo B48, thyroid hormones, homocysteine, vitamin B12, and folic acid were determined by ELISA. Spectrophotometry was used to determine serum lipid concentrations. RESULTS: The mean age of the case group was 69 ± 6.4 years and that of the control group was 67 ± 4.2 years. There were differences between the control and case groups in serum levels of homocysteine, apo B48, ATG5, hsCRP, LDL, HDL, cholesterol, and VitB12 (p < 0.05). According to the results of the ROC curve, measurements of serum levels of ATG5, homocysteine, and apo B48 have excellent performance in distinguishing patients with Alzheimer's disease from patients without AD. CONCLUSIONS: This study suggests that the measurement of serum levels of ATG5, homocysteine, and apo B48, along with other available biomarkers, can be helpful in the diagnosis and management of patients with AD in the early stages of their disease.
Assuntos
Doença de Alzheimer , Humanos , Pessoa de Meia-Idade , Idoso , Doença de Alzheimer/diagnóstico , Apolipoproteína B-48 , Homocisteína , Ácido Fólico , Vitamina B 12 , Hormônios Tireóideos , Proteína 5 Relacionada à AutofagiaRESUMO
OBJECTIVE: We aimed to investigate the relationship between homocysteine levels and MTHFR C677T polymorphisms and acute ischemic vascular events and focused on the differential effects of the MTHFR C677T polymorphisms on the burden and location of AMI and ACI. PATIENTS AND METHODS: 102 acute cerebral infarction (ACI) and acute myocardial infarction (AMI) patients who were admitted to the First Hospital of Jilin University in northeast China as the patient group, 83 healthy people who were hospitalized during the same period served as a control group. MTHFR C677T genotypes were identified via Polymerase Chain Reaction (PCR)-Fluorescent Probe Method. RESULTS: Patient group had higher serum homocysteine levels (p=0.013), lower serum folic acid (p<0.001), and Vit B12 levels (p=0.004) compared to the control group. Homocysteine levels in the patient group with the TT genotypes of the MTHFR C677T polymorphisms were higher than those with the CC and CT genotypes (p<0.05). Folic acid levels in the patients with TT genotypes were lower than those with the CC genotypes (p<0.05), but not in the control group (p>0.05). There were negative and significant associations between serum homocysteine levels and serum vitamin B12 levels in the control group (r=-0.234, p=0.033), but not between serum homocysteine levels and serum folic acid levels (r=-0.103, p=0.355). Conversely, there was a negative and significant association between serum homocysteine levels and serum folic acid levels in the patients' group (r=-0.257, p=0.01), but not between serum homocysteine levels and serum vitamin B12 levels (r=-0.185, p=0.64). No statistically significant differences in MTHFR C677T genotype and C/T alleles distribution were investigated between the patient and control group (p>0.05). The MTHFR C677T polymorphism did not differentially affect the burden and location of AMI and ACI. CONCLUSIONS: Homocysteine played a common role in atherosclerosis-related acute ischemic vascular events. These correlations were modified by MTHFR C677T polymorphisms and influenced by folic acid levels. The MTHFR C677T polymorphisms were not directly related to acute ischemic vascular events, nor did they differentially affect the burden and location of AMI and ACI.
Assuntos
Isquemia Encefálica , Metilenotetra-Hidrofolato Redutase (NADPH2) , Infarto do Miocárdio , Acidente Vascular Cerebral , Humanos , Ácido Fólico , Homocisteína , Metilenotetra-Hidrofolato Redutase (NADPH2)/genéticaRESUMO
OBJECTIVES: Hyperhomocysteinaemia (Hcy) is an independent risk factor for cardiovascular and cerebrovascular diseases. MicroRNA (miR)-18a-5p is closely related to cardiovascular diseases. This study aims to investigate the effects of miR-18a-5p on homocysteine (Hcy)-induced myocardial cells injury. METHODS: H9c2 cells were transfected with miR-18a-5p mimic/miR-18a-5p mimic negative control (NC) or combined with Hcy for intervention, and untreated cells were set as a control group. The transfection efficiency was verified by real-time RT-PCR, and cell counting kit-8 (CCK-8) assay was used to determine cell viability. Flow cytometry was used to detect apoptosis and reactive oxygen species (ROS) levels. Western blotting was performed to measure the protein levels of microtubule-associated protein 1 light chain 3 (LC3)-I, LC3-II, Beclin1, p62, Bax, Bcl-2, and Notch2. Dual luciferase reporter assay was used to detect the interaction of miR-18a-5p with Notch2. RESULTS: Compared with the control, treatment with Hcy or transfection with miR-18a-5p mimic alone, or combined treatment with Hcy and miR-18a-5p mimic/miR-18a-5p mimic NC significantly reduced the H9c2 cell viability, promoted apoptosis and ROS production, up-regulated the expressions of Bax and Beclin, down-regulated the expressions of Bcl-2, p62, and Notch2, and increased the ratio of LC3-II/LC3-I (all P<0.05). Compared with the combined intervention of miR-18a-5p mimic NC and Hcy group, the above indexes were more significantly changed in the combined intervention of miR-18a-5p mimic and Hcy group, and the difference between the 2 groups was statistically significant (all P<0.05). There is a targeted binding between Notch2 and miR-18a-5p. CONCLUSIONS: MiR-18a-5p could induce autophagy and apoptosis via increasing ROS production in cardiomyocytes, and aggravate Hcy-induced myocardial injury. Notch2 is a target of miR-18a-5p.
Assuntos
Autofagia , MicroRNAs , Miócitos Cardíacos , Apoptose/genética , Autofagia/genética , Proteína X Associada a bcl-2 , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Espécies Reativas de Oxigênio , Ratos , Animais , Miócitos Cardíacos/efeitos dos fármacos , Homocisteína/efeitos adversos , Hiper-HomocisteinemiaRESUMO
Levodopa (L-dopa) and catechol-O-methyltransferase (COMT) inhibition are widely used therapeutics in Parkinson's disease (PD). Despite their therapeutic effects, it was raised that nutrients involved in one-carbon metabolism can be deteriorated by PD therapies. The aim of this meta-analysis was to investigate the impact of L-dopa and COMT inhibitors on levels of homocysteine (Hcy), vitamin B12 and folate in patients with PD. A total of 35 case-control studies from 14 different countries were selected through PubMed, MEDLINE and Google Scholar and were meta-analyzed. In the L-dopa group, the Hcy level was higher compared to the PD without L-dopa group (SMD: 5.11 µmol/L, 95% CI: 3.56 to 6.66). Moreover, vitamin B12 and folate levels in the L-dopa group were lower compared to the healthy control (SMD: -62.67 pg/mL, 95% CI: -86.53 to -38.81; SMD: -0.89 ng/mL, 95% CI: -1.44 to -0.33, respectively). The COMT inhibitor group showed lower levels of Hcy (SMD: -3.78 µmol/L, 95% CI: -5.27 to -2.29) and vitamin B12 (SMD: -51.01 pg/mL, 95% CI: -91.45 to -10.57), but higher folate levels (SMD: 1.78 ng/mL, 95% CI: -0.59 to 4.15) compared to the L-dopa group. COMT inhibitors may ameliorate L-dopa-induced hyper-homocysteine and folate deficiency but exacerbate vitamin B12 deficiency.
Assuntos
Inibidores de Catecol O-Metiltransferase , Doença de Parkinson , Humanos , Carbono/metabolismo , Ácido Fólico/uso terapêutico , Homocisteína , Levodopa/farmacologia , Doença de Parkinson/tratamento farmacológico , Vitamina B 12/uso terapêutico , Vitaminas/uso terapêutico , Inibidores de Catecol O-Metiltransferase/uso terapêuticoRESUMO
BACKGROUND: Atherosclerosis is one of the most important global health hazards and air pollution (AP, PM2.5) has been implicated. In addition to traditional risk factors hyperhomocysteinemia (HC) has been recognized in many parts of China related to risk of stroke. METHODS: To evaluate the impact of HC (homocysteine >14µmol/l) and PM2.5 air pollution on atherogenesis in modernizing China, we studied 756 asymptomatic Chinese in China from 1998-2007. PM2.5 exposure, HC, folate, and methylenetetrahydrofolate reductase (MTHFR) C/T genotype were evaluated. Brachial flow-mediated dilation (FMD) and carotid intima-media thickness (IMT) were measured by ultrasound. Locations were categorized as zones 1, 2 and 3, with increasing PM2.5 exposure. RESULTS: HC was higher (19.4±13.1 and 27.1±25.1µmol/l) in high PM2.5-polluted zones 2 and 3 than in zone 1 (9.7±4.5µmol/l, p<0.0015). The top HC tertile was characterized by lower folate and vitamin B12, but a higher proportion of the MTHFR TT genotype, Metabolic Syndrome (MS) and PM2.5 level (p=0.0018). FMD was significantly lower (7.3±2.3%) and carotid IMT thicker (0.63±0.12mm) in the top HC tertile, compared with low HC tertile (8.4±2.5%, p<0.0001; 0.57±0.1mm, p<0.0001 respectively). Similar differences in FMD and IMT were seen in zones 2 and 3, compared with zone 1 (p<0.0001). On multivariate regression, HC was related to male gender (beta=0.106, p=0.021), MTHFR-TT (beta=0.935, p<0.0001), locations (beta=0.230, p<0.0001) and folate-MTHFR interaction (beta=-0.566, p<0.0001). FMD was related to age (beta= -0.221; p<0.0001), male gender (beta= -0.194, p=0.001) PM2.5 and location (beta=-0.285 to -0.303, p<0.0001). Carotid IMT was related to PM2.5 (beta=0.173, p<0.0001), HC (0.122, p=0.006) but not to MTHFR or location, independent of age, gender, MS, and LDL-C. No significant HC-PM2.5 interaction effect on FMD and IMT was observed. CONCLUSION: HC and PM2.5 pollution but not MTHFR genotype were both related to carotid IMT, independent of other traditional risk factors. This has potential implications in dietary and AP strategies for atherosclerosis prevention in China.
Assuntos
Poluição do Ar , Aterosclerose , Hiper-Homocisteinemia , Metilenotetra-Hidrofolato Redutase (NADPH2) , Humanos , Masculino , Aterosclerose/genética , Espessura Intima-Media Carotídea , População do Leste Asiático , Ácido Fólico , Genótipo , Homocisteína , Hiper-Homocisteinemia/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Material Particulado , FemininoRESUMO
BACKGROUND: Although a number of health outcomes such as CVDs, metabolic-related outcomes, neurological disorders, pregnancy outcomes, and cancers have been identified in relation to B vitamins, evidence is of uneven quality and volume, and there is uncertainty about putative causal relationships. OBJECTIVES: To explore the effects of B vitamins and homocysteine on a wide range of health outcomes based on a large biorepository linking biological samples and electronic medical records. METHODS: First, we performed a phenome-wide association study (PheWAS) to investigate the associations of genetically predicted plasma concentrations (genetic component of the circulating concentrations) of folate, vitamin B6, vitamin B12, and their metabolite homocysteine with a wide range of disease outcomes (including both prevalent and incident events) among 385,917 individuals in the UK Biobank. Second, 2-sample Mendelian randomization (MR) analysis was used to replicate any observed associations and detect causality. We considered MR P <0.05 as significant for replication. Third, dose-response, mediation, and bioinformatics analyses were carried out to examine any nonlinear trends and to disentangle the underlying mediating biological mechanisms for the identified associations. RESULTS: In total, 1117 phenotypes were tested in each PheWAS analysis. After multiple corrections, 32 phenotypic associations of B vitamins and homocysteine were identified. Two-sample MR analysis supported that 3 of them were causal, including associations of higher plasma vitamin B6 with lower risk of calculus of kidney (OR: 0.64; 95% CI: 0.42, 0.97; P = 0.033), higher homocysteine concentration with higher risk of hypercholesterolemia (OR: 1.28, 95% CI: 1.04, 1.56; P = 0.018), and chronic kidney disease (OR: 1.32, 95% CI: 1.06, 1.63; P = 0.012). Significant nonlinear dose-response relationships were observed for the associations of folate with anemia, vitamin B12 with vitamin B-complex deficiencies, anemia and cholelithiasis, and homocysteine with cerebrovascular disease. CONCLUSIONS: This study provides strong evidence for the associations of B vitamins and homocysteine with endocrine/metabolic and genitourinary disorders.
Assuntos
Complexo Vitamínico B , Gravidez , Feminino , Humanos , Bancos de Espécimes Biológicos , Ácido Fólico , Vitamina B 12 , Vitamina B 6 , Biomarcadores , Vitamina A , Vitamina K , Reino Unido , Homocisteína , Análise da Randomização MendelianaRESUMO
Hypertension associated with hyperhomocysteinemia (HHcy) accounts for 75% of hypertension in China. HHcy plays a synergistic role with hypertension in vascular injury and significantly increases the incidence of cardiovascular and cerebrovascular diseases. The present study aimed to explore the molecular mechanism of HHcy-induced arterial injury in hypertension. Spontaneously hypertensive rats (SHR) were injected intraperitoneally with DL-homocysteine (Hcy) to construct the model of hypertension associated with HHcy (HHcy + SHR). Biological network was employed to identify the material basis of arterial injury in hypertension associated with HHcy. The prediction molecules in oxidative stress and inflammation pathways were experimentally verified by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB) analysis. The HHcy + SHR group significantly increased oxidative stress pathway molecules: nicotinamide adenine dinucleotide phosphate oxidase (Nox); inflammatory pathway molecules: vascular adhesion protein-1 (VAP-1), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-a); as well as inflammatory pathway regulatory factors: nuclear factor-κ-gene binding (NF-κB) p65 and protein kinase B (Akt1). Among them, IL-6 was also significantly increased in the HHcy group. Both oxidative stress and inflammation contributed to the arterial injury of hypertension associated with HHcy, and inflammation mechanism might play a leading role in HHcy aggravating arterial injury, at least partially through the Akt1/NF-κB p65/IL-6 signaling pathway.
Assuntos
Hiper-Homocisteinemia , Hipertensão , Lesões do Sistema Vascular , Ratos , Animais , Ratos Endogâmicos SHR , NF-kappa B/metabolismo , Interleucina-6/genética , Hiper-Homocisteinemia/complicações , Lesões do Sistema Vascular/complicações , Inflamação/metabolismo , Hipertensão/complicações , HomocisteínaRESUMO
BACKGROUND: Evidence on the association of serum folate and homocysteine concentrations with risk of mortality in the general population is unclear. OBJECTIVES: This study aimed to examine the associations of serum folate and homocysteine concentrations with all-cause, CVD, and cancer mortality risk in Korean men and women aged ≥40 y. METHODS: In this population-based prospective cohort study, serum folate and homocysteine concentrations were measured in a subset of participants enrolled between 2005 and 2012. A total of 21,260 participants were linked to mortality data from the survey date to 31 December 2019. Cox proportional hazards models and restricted cubic splines were used to identify the associations of serum folate and homocysteine concentrations with mortality. RESULTS: During a median follow-up of 12.3 y, 2501, 549, and 842 deaths were attributed to all-cause, CVD, and cancer, respectively. The prevalence of folate deficiency and hyperhomocysteinemia were higher in men than in women. In men, a nonlinear inverse association was observed between serum folate concentrations and all-cause mortality. Men in the third quartile of serum folate concentrations exhibited a lower risk of all-cause mortality (HR: 0.85; 95% CI: 0.73, 0.99) than those in the lowest quartile. Serum homocysteine concentration was positively associated with all-cause and CVD mortality. Men and women in the highest compared with those in the lowest serum homocysteine quartile showed a higher risk of CVD mortality (HR: 1.60; 95% CI: 1.07, 2.39; and HR: 1.79; 95% CI: 1.11, 2.89, respectively). Hyperhomocysteinemia combined with folate deficiency was associated with increased all-cause, CVD, and cancer-related mortality rates. CONCLUSIONS: Higher serum homocysteine and lower serum folate concentrations were associated with an increased risk of all-cause, CVD, and cancer-related mortality in Korean adults. The finding of a nonlinear inverse relationship between serum folate concentration and mortality in men warrants further investigation.
Assuntos
Doenças Cardiovasculares , Deficiência de Ácido Fólico , Hiper-Homocisteinemia , Neoplasias , Masculino , Adulto , Humanos , Feminino , Estudos Prospectivos , Ácido Fólico , Deficiência de Ácido Fólico/complicações , República da Coreia/epidemiologia , Homocisteína , Fatores de RiscoRESUMO
OBJECTIVE: The aim of this study was to describe homocysteine concentrations in overweight and obese children and adolescents and relate them to blood pressure levels, renal function, and insulin resistance. METHODS: This is a cross-sectional and observational study with 64 overweight children and adolescents (mean age: 11.6±3.5 years) in outpatient follow-up. The following parameters were evaluated: body mass index z-score, waist-to-height circumference ratio, pubertal stage, blood pressure, serum homocysteine, glycemia, insulin, lipid profile, renal function, high-sensitivity C-reactive protein, microalbuminuria, and creatinuria. Statistical analysis: analysis of variance and logistic regression (dependent variable: homocysteine) (p<0.05). RESULTS: The mean body mass index z-score was 2.9±1.1. The mean homocysteine concentrations were 8.6±2.2 µmol/L (10th and 90th percentiles: 6.6 and 11.2 µmol/L, respectively), with no difference when compared with children with severe obesity and obesity/overweight (p=0.431). High values of waist-to-height ratio (93.8%), systolic blood pressure (18.8%), diastolic blood pressure (12.5%), glycemia (4.7%), low-density lipoprotein cholesterol (31.1%), triglycerides (35.9%), non-high-density lipoprotein cholesterol (34.4%), and microalbuminuria (21.9%) were obtained. The mean glomerular filtration rate was 122.9±24.6 mL/min/1.73 m². Homocysteine concentrations were not associated with any of the studied variables (R²=0.095). CONCLUSION: Homocysteine concentrations in overweight children and adolescents (mean 8.6±2.2 µmol/L) were not associated with body mass index z-score, blood pressure, renal function, and insulin resistance.
Assuntos
Homocisteína , Resistência à Insulina , Sobrepeso , Obesidade Pediátrica , Adolescente , Criança , Humanos , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Estudos Transversais , Sobrepeso/complicações , Obesidade Pediátrica/complicações , Fatores de Risco , Homocisteína/sangueRESUMO
Some studies have indicated that elevated homocysteine (Hcy) levels and intestinal flora may be involved in schizophrenia (SZ) cognition pathophysiology. This study was the first to investigate the association among Hcy, intestinal flora and schizophrenia cognition. Here, 140 individuals were divided into two groups: SZ patients (N = 68) and healthy controls (HCs, N = 72). Participant data on serum Hcy levels, intestinal flora and cognitive function evaluation using the MATRICS Consensus Cognitive Battery (MCCB) were collected. Clinical symptoms of patients were evaluated using the Positive and Negative Syndrome Scale. Serum Hcy levels and the incidence of hyperhomocysteinaemia were considerably increased in SZ patients compared with HCs. Hcy levels were significantly negatively associated with verbal learning index scores (r = -0.425, p < 0.001) but positively associated with Eubacterium (r = 0.32, p = 0.007), Lactobacillus (r = 0.32, p = 0.008), Corynebacterium (r = 0.26, p = 0.035), Mogibacterium (r = 0.31, p = 0.01), and Bulleidia (r = 0.31, p = 0.01) in SZ patients. Our findings suggest that serum Hcy levels are associated with cognitive function and intestinal flora in SZ patients. However, the mechanism of the interaction between Hcy and intestinal flora and its effects on cognitive function in SZ patients requires further investigation.
Assuntos
Transtornos Cognitivos , Microbioma Gastrointestinal , Esquizofrenia , Humanos , Cognição , Transtornos Cognitivos/diagnóstico , HomocisteínaRESUMO
Epigenetic effects of environmental pollutants may be related to carcinogenesis. This study aimed to explore the association between the global DNA methylation marker: 5-methyl-2-deoxycytidine (5mdC) and renal cell carcinoma (RCC), and further investigated whether plasma folate and vitamin B12 levels and 5mdC modified the association between blood cadmium concentrations and RCC. We recruited 174 RCC patients and 673 non-RCC controls. Blood cadmium concentrations, plasma folate and vitamin B12 levels were measured. The amount of 5mdC in the DNA sample was expressed as percentages of the total cytosine content. An increase of 5mdC (%) and plasma folate and vitamin B12 levels were associated with decreasing odds ratio (OR) of RCC. Although plasma folate levels were not directly associated with 5mdC (%), a combined effect was observed with the odds of low plasma folate levels and low 5mdC (%) were greater among RCC patients compared to controls (OR (95% confidence interval, CI) = 11.86 (5.27-26.65)). Additionally, we observed that the odds of low plasma folate and high blood cadmium levels were greater among RCC patients than in controls (OR (95% CI): 8.15 (1.39-7.13)). This study provides suggestive evidence that plasma folate levels may modify the associations between 5mdC (%) or blood cadmium concentrations and RCC.
Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Metilação de DNA , Cádmio , Estudos de Casos e Controles , Ácido Fólico , Vitamina B 12 , Vitaminas , HomocisteínaRESUMO
Suppressor of mek1 (Dictyostelium) homolog 2 (Smek2), was identified as one of the responsible genes for diet-induced hypercholesterolemia (DIHC) of exogenously hypercholesterolemic (ExHC) rats. A deletion mutation in Smek2 leads to DIHC via impaired glycolysis in the livers of ExHC rats. The intracellular role of Smek2 remains obscure. We used microarrays to investigate Smek2 functions with ExHC and ExHC.BN-Dihc2BN congenic rats that harbor a non-pathological Smek2 allele from Brown-Norway rats on an ExHC background. Microarray analysis revealed that Smek2 dysfunction leads to extremely low sarcosine dehydrogenase (Sardh) expression in the liver of ExHC rats. Sarcosine dehydrogenase demethylates sarcosine, a byproduct of homocysteine metabolism. The ExHC rats with dysfunctional Sardh developed hypersarcosinemia and homocysteinemia, a risk factor for atherosclerosis, with or without dietary cholesterol. The mRNA expression of Bhmt, a homocysteine metabolic enzyme and the hepatic content of betaine (trimethylglycine), a methyl donor for homocysteine methylation were low in ExHC rats. Results suggest that homocysteine metabolism rendered fragile by a shortage of betaine results in homocysteinemia, and that Smek2 dysfunction causes abnormalities in sarcosine and homocysteine metabolism.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Hipercolesterolemia , Hiper-Homocisteinemia , Fosfoproteínas Fosfatases , Sarcosina Desidrogenase , Animais , Ratos , Betaína/metabolismo , Glucose/metabolismo , Homocisteína/metabolismo , Hipercolesterolemia/genética , Hiper-Homocisteinemia/complicações , Fígado/metabolismo , Mutação , Ratos Endogâmicos BN , Sarcosina/metabolismo , Sarcosina Desidrogenase/deficiência , Erros Inatos do Metabolismo dos Aminoácidos/genética , Fosfoproteínas Fosfatases/genéticaRESUMO
Methylenetetrahydrofolate reductase (MTHFR) plays a major role in the metabolism of folates and homocysteine, which in turn can affect gene expression and ultimately promote the development of breast cancer. Thus, mutations in the MTHFR gene could influence homocysteine, methionine, and S-adenosylmethionine levels and, indirectly, nucleotide levels. Imbalance in methionine and S-adenosylmethionine synthesis affects protein synthesis and methylation. These changes, which affect gene expression, may ultimately promote the development of breast cancer. We therefore hypothesized that such mutations could also play an important role in the occurrence and pathogenesis of breast cancer in a Malian population. In this study, we used the PCR-RFLP technique to identify the different genotypic profiles of the C677T MTHFR polymorphism in 127 breast cancer women and 160 healthy controls. The genotypic distribution of the C677T polymorphism in breast cancer cases was 88.2% for CC, 11.0% for CT, and 0.8% for TT. Healthy controls showed a similar distribution with 90.6% for CC, 8.8% for CT, and 0.6% for TT. We found no statistical association between the C677T polymorphism and breast cancer risk for the codominant models CT and TT (p > 0.05). The same trend was observed when the analysis was extended to other genetic models, including dominant (p = 0.50), recessive (p = 0.87), and additive (p = 0.50) models. The C677T polymorphism of MTHFR gene did not influence the risk of breast cancer in the Malian samples.
Assuntos
Neoplasias da Mama , Metilenotetra-Hidrofolato Redutase (NADPH2) , Feminino , Humanos , Neoplasias da Mama/genética , Homocisteína , Mali , Metionina , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , S-AdenosilmetioninaRESUMO
Biothiols mainly include cysteine (Cys), homocysteine (Hcy) and glutathione (GSH), which play an important role in life activities and abnormal changes in their concentrations are closely related to certain diseases. Therefore, the quantitative tracking and analysis of biothiols in living organisms has become a hot research topic in recent years. In this work, a coumarin-based fluorescent probe COUN was designed and synthesized for the comparable color recognition of Cys/Hcy and GSH by introducing the phenylethynyl group as the recognition site of biothiols, which showed significant fluorescence enhancement and green fluorescence under the UV light at 365 nm. The probe specifically recognized Hcy, showing 40-fold fluorescence enhancement and strong green fluorescence at 492 nm. Moreover, there was a good linear relationship between the fluorescence intensity of the probe and certain concentrations of Cys/Hcy and GSH, with detection limits of 36.6 nM, 86.4 nM, and 174 nM, respectively. The recognition mechanism of COUN to distinguish Cys/Hcy and GSH was studied by TDDFT calculations. More importantly, COUN was successfully used for imaging biothiols in living cells. The results showed that this probe could provide an effective contribution to the understanding of the role of biothiols, especially Hcy.
Assuntos
Cisteína , Corantes Fluorescentes , Cisteína/análise , Glutationa/análise , Cumarínicos , Espectrometria de Fluorescência/métodos , HomocisteínaRESUMO
Breastfeeding is the gold standard for early nutrition. Metabolites from the one-carbon metabolism pool are crucial for infant development. The aim of this study is to compare the breast-milk one-carbon metabolic profile to other biofluids where these metabolites are present, including cord and adult blood plasma as well as cerebrospinal fluid. Breast milk (n = 142), cord blood plasma (n = 23), maternal plasma (n = 28), aging adult plasma (n = 91), cerebrospinal fluid (n = 92), and infant milk formula (n = 11) samples were analyzed by LC-MS/MS to quantify choline, betaine, methionine, S-adenosylmethionine, S-adenosylhomocysteine, total homocysteine, and cystathionine. Differences between groups were visualized by principal component analysis and analyzed by Kruskal-Wallis test. Correlation analysis was performed between one-carbon metabolites in human breast milk. Principal component analysis based on these metabolites separated breast milk samples from other biofluids. The S-adenosylmethionine (SAM) concentration was significantly higher in breast milk compared to the other biofluids and was absent in infant milk formulas. Despite many significant correlations between metabolites in one-carbon metabolism, there were no significant correlations between SAM and methionine or total homocysteine. Together, our data indicate a high concentration of SAM in breast milk, which may suggest a strong demand for this metabolite during infant early growth while its absence in infant milk formulas may indicate the inadequacy of this vital metabolic nutrient.
Assuntos
Leite Humano , S-Adenosilmetionina , Adulto , Criança , Lactente , Feminino , Humanos , S-Adenosilmetionina/metabolismo , Cromatografia Líquida , Leite Humano/metabolismo , Carbono , Espectrometria de Massas em Tandem , Metionina/metabolismo , Racemetionina , S-Adenosil-Homocisteína/metabolismo , HomocisteínaRESUMO
Age-related macular degeneration (AMD) is a major cause of blindness. Recent studies have reported impaired glycolysis in AMD patients with a high lactate/pyruvate ratio. Elevated homocysteine (Hcy) (Hyperhomocysteinemia, HHcy) was observed in several clinical studies, reporting an association between HHcy and AMD. We established the effect of HHcy on barrier function, retinal pigment epithelium (RPE) structure, and induced choroidal neovascularization (CNV) in mice. We hypothesize that HHcy contributes to AMD by inducing a metabolic switch in the mitochondria, in which cells predominantly produce energy by the high rate of glycolysis, or "Warburg", effect. Increased glycolysis results in an increased production of lactate, cellular acidity, activation of angiogenesis, RPE barrier dysfunction, and CNV. Evaluation of cellular energy production under HHcy was assessed by seahorse analysis, immunofluorescence, and western blot experiments. The seahorse analysis evaluated the extracellular acidification rate (ECAR) as indicative of glycolysis. HHcy showed a significant increase in ECAR both in vivo using (Cystathionine ß-synthase) cbs+/- and cbs-/- mice retinas and in vitro (Hcy-treated ARPE-19) compared to wild-type mice and RPE cells. Moreover, HHcy up-regulated glycolytic enzyme (Glucose transporter-1 (GlUT-1), lactate dehydrogenase (LDH), and hexokinase 1 (HK1)) in Hcy-treated ARPE-19 and primary RPE cells isolated from cbs+/+, cbs+/-, and cbs-/- mice retinas. Inhibition of GLUT-1 or blocking of N-methyl-D-aspartate receptors (NMDAR) reduced glycolysis in Hcy-treated RPE and improved albumin leakage and CNV induction in Hcy-injected mice eyes. The current study suggests that HHcy causes a metabolic switch in the RPE cells from mitochondrial respiration to glycolysis during AMD and confirms the involvement of NMDAR in this process. Therefore, targeting Glycolysis or NMDAR could be a novel therapeutic target for AMD.
Assuntos
Neovascularização de Coroide , Hiper-Homocisteinemia , Degeneração Macular , Camundongos , Animais , Células Cultivadas , Degeneração Macular/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Hiper-Homocisteinemia/metabolismo , Neovascularização de Coroide/metabolismo , Cistationina beta-Sintase/metabolismo , Homocisteína/metabolismoRESUMO
Microfluidic paper-based analytical devices modified with molecularly imprinted polymers (µPADs@MIPs) were developed for fluorescent detection of targeted thiols via in situ UV-induced formation of quantum dots (µPADs@MIPs@QDs). The selectivity enhancement by the MIP layer formed on the filter paper surface was demonstrated for the isolation of L-homocysteine from wine. Followed by the addition of metal precursors solution (Zn/Cd/Cu) and UV irradiation, fluorescent quantum dots were formed thus enabling quantitative detection of the thiol (serving as a QD capping agent). The effect of different semiconductors was investigated to achieve a lower band gap and higher fluorescence intensity. Increasing fluorescence intensity in the presence of thiol groups was obtained for the following precursors mixture composition: ZnCdCu/S > ZnCd/S > ZnCu/S > ZnS. The proposed method has a good relationship between the fluorescence intensity of ZnCdCu/S QDs and L-homocysteine in a linear range from 0.74 to 7.40 µM with a limit of detection (LOD) and quantification (LOQ) of 0.51 and 1.71 µM respectively. This method was applied for the determination of L-homocysteine in white wine with RSD under 6.37%.
Assuntos
Impressão Molecular , Pontos Quânticos , Polímeros Molecularmente Impressos , Polímeros , Microfluídica , Impressão Molecular/métodos , Corantes Fluorescentes , HomocisteínaRESUMO
INTRODUCTION: The common practice of supplementing folic acid during pregnancy and the absence of such guidelines for vitamin B12 lead to an imbalance of these vitamins, especially in developing countries like India, where many women are vitamin B12 deficient. METHODS: The present study was designed to explore the effect of low vitamin B12 in combination with different levels of folic acid in the parental diet on fetal growth parameters and maternal reproductive performance in a transgenerational manner. The reversibility of these effects was studied by shifting the mice to a regular diet in the F1 generation in the case of transient groups and continued on the same diet in the sustained groups after the dietary exposure in the F0 generation. RESULTS: Vitamin B12 deficiency and different levels of folic acid resulted in the decreased placental and fetal weight of the F1 generation. Surprisingly, a decreased placental weight, low fetal weight, and reduced crown-rump length and head circumference were observed in F2 fetuses of vitamin B12 deficient with folate over-supplemented (BDFO) transient group, i.e. when F1 mice were shifted to normal diet conditions. Reduced follicles in ovaries and alteration in placental pathology in all the F0 groups and BDFO of the F1 transient group were also seen. DISCUSSION: Overall, the study revealed that dietary imbalance of vitamin B12 and folic acid, particularly B12 deficiency with over-supplemented folic acid, negatively affects placental and fetal development and maternal reproductive performance. Such effects are passed on to the next generation too.