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1.
Environ Health ; 21(1): 48, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35513839

RESUMO

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) and its DNA adducts has been suggested to increase the risk of preterm birth (PB). Yet, few studies have been conducted to investigate this association, and the role of dietary nutrients intakes including vitamins, folate, and carotene during pre- and post-conception on this association has not been studied. METHODS: Building upon a birth cohort in Taiyuan China, we conducted a nested case control study including 83 PB and 82 term births. Benzo[a]pyrene (BaP)-DNA adducts were measured by an improved LC-MC/MC analytic method. Dietary nutrient intakes were estimated from food frequency questionnaire using the Chinese Standard Tables of Food Consumption. Multivariable logistic regression model was used to examine the associations. RESULTS: Increased risk of PB was observed as per interquartile increase in maternal BaP-DNA adduct level (OR = 1.27, 95%CI 0.95-1.67). Compared to low level (below mean) of maternal adducts, high level (above mean) of adducts was associated with the risk of PB (OR = 2.05, 95%CI 1.05-4.01). After stratified by dietary nutrients intakes, high adducts levels were associated with approximately 2-fourfold times increases in risk of PB among women with low vitamin A, C, E, folate, and carotene intakes during pre- and/or post-conception. Stronger stratified associations were consistently seen during preconception. Similar patterns were observed after additional adjustment for supplementation. CONCLUSIONS: Our study supports the hypothesis that high level of maternal PAHs exposure was significantly associated with increased risk of PB, and provides the first evidence that dietary vitamins, carotene, and folate intake levels may modify this association during different pregnancy windows. Our findings are relevant to identify recommendation for environment management and prenatal nutrition regarding pregnant women and newborns. Further investigation in other populations is warranted.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Nascimento Prematuro , Benzo(a)pireno/análise , Coorte de Nascimento , Carotenoides , Estudos de Casos e Controles , China/epidemiologia , Adutos de DNA , Feminino , Ácido Fólico , Humanos , Recém-Nascido , Masculino , Gravidez , Nascimento Prematuro/induzido quimicamente , Nascimento Prematuro/epidemiologia , Vitamina A , Vitaminas
2.
Biochem Biophys Res Commun ; 492(1): 109-115, 2017 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-28802581

RESUMO

Studies have identified that PKM2 is related to the development of glucose intolerance and insulin resistance in rodents and humans. However, the underlying mechanism remains largely unknown. In the present study, we found that PKM2 expression was significantly elevated in insulin-resistant hepatic tissues and hepatocytes, implicating an association between PKM2 expression and hepatic insulin resistance (IR). In vitro study revealed that overexpression of PKM2 impaired the insulin signaling pathway by decreasing the phosphorylation of protein kinase B (Akt) and glycogen synthase kinase-3ß (GSK3ß). Furthermore, PKM2 overexpression enhanced the effects of PA on the lipid accumulation, the expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) and hepatic glucose uptake. Intriguingly, PA-induced insulin resistance was suppressed following by the ablation of PKM2 in HepG2 cells. We also found that STAT3 was significantly activated by PKM2 overexpression. Moreover, we identified that PKM2 could interact directly with STAT3. Taken together, these studies demonstrate that PKM2 may promote hepatic IR via STAT3 pathway and would provide a new insight into dissecting the molecular pathogenesis of hepatic insulin resistance.


Assuntos
Proteínas de Transporte/metabolismo , Resistência à Insulina , Proteínas de Membrana/metabolismo , Palmitatos/farmacologia , Fator de Transcrição STAT3/metabolismo , Hormônios Tireóideos/metabolismo , Células Hep G2 , Humanos , Células Tumorais Cultivadas , Proteínas de Ligação a Hormônio da Tireoide
4.
Gen Comp Endocrinol ; 247: 66-73, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28111233

RESUMO

Oxidative stress plays a significant role in the development of hepatic insulin resistance, but the underlying molecular mechanisms remain poorly understood. In this study, we discovered that C-terminal-binding protein 2 (CtBP2) level was decreased in insulin resistance. Taking into account the relationship between CtBP family protein (ANGUSTIFOLIA) and reactive oxygen species (ROS) accumulation, we conjectured CtBP2 was involved in insulin resistance through ROS induced stress. In order to verify this hypothesis, we over-expressed CtBP2 in palmitate (PA) treated HepG2 cells. Here, we found that over-expression of CtBP2 ameliorated insulin sensitivity by increasing phosphorylation of glycogen synthase kinase 3ß (GSK3ß) and protein kinase B (AKT). These data suggest that CtBP2 plays a critical role in the development of insulin resistance. Moreover, CtBP2 reversed the effects of PA on ROS level, lipid accumulation, hepatic glucose uptake and gluconeogenesis. We also found that over-expression of CtBP2 could suppress PA induced c-jun NH2 terminal kinase (JNK) activation. Furthermore, JNK inhibitor SP600125 was shown to promote the effect of CtBP2 on insulin signaling. Thus, we demonstrated that CtBP2 ameliorated PA-induced insulin resistance via ROS-dependent JNK pathway.


Assuntos
Oxirredutases do Álcool/metabolismo , Resistência à Insulina , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas do Tecido Nervoso/metabolismo , Palmitatos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Animais , Proteínas Correpressoras , Regulação para Baixo/efeitos dos fármacos , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Células Hep G2 , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL
5.
Biochem Biophys Res Commun ; 467(3): 527-33, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26449452

RESUMO

High-fat diet (HFD) and inflammation are key contributors to insulin resistance (IR) and Type 2 diabetes mellitus (T2DM). With HFD, plasma free fatty acids (FFAs) can activate the nuclear factor-κB (NF-κB) in target tissues, then initiate negative crosstalk between FFAs and insulin signaling. However, the molecular link between IR and inflammation remains to be identified. We here reported that tumor necrosis factor receptor-associated factor 1 (TRAF1), an adapter in signal transduction, was involved in the onset of IR in hepatocytes. TRAF1 was significantly up-regulated in insulin-resistant liver tissues and palmitate (PA)-treated HepG2 cells. In addition, we showed that depletion of TRAF1 led to inhibition of the activity of NF-κB. Given the fact that the activation of NF-κB played a facilitating role in IR, the phosphorylation of Akt and GSK3ß was also analyzed. We found that depletion of TRAF1 markedly reversed PA-induced attenuation of the phosphorylation of Akt and GSK3ß in the cells. The accumulation of lipid droplets in hepatocyte and expression of two key gluconeogenic enzymes, PEPCK and G6Pase, were also determined and found to display a similar tendency with the phosphorylation of Akt and GSK3ß. Glucose uptake assay indicated that knocking down TRAF1 blocked the effect of PA on the suppression of glucose uptake. These data implicated that TRAF1 knockdown might alleviate PA-induced IR in HepG2 cells through NF-κB pathway.


Assuntos
Técnicas de Silenciamento de Genes , Resistência à Insulina , NF-kappa B/metabolismo , Palmitatos/farmacologia , Fator 1 Associado a Receptor de TNF/genética , Animais , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
6.
Biochem Biophys Res Commun ; 465(4): 670-7, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26301632

RESUMO

Studies have identified that type 2 diabetes mellitus (T2DM) patients displayed higher levels of plasma peroxiredoxin1(PRDX1) than non-diabetics. However, the impact of PRDX1 on insulin resistance and the underlying mechanism remains totally unknown. Here, we investigated the influence of PRDX1 on hepatic insulin resistance. We showed that the protein and mRNA levels of PRDX1 were significantly elevated under insulin-resistant conditions. In addition, we showed that interference of PRDX1 ameliorated palmitate-induced insulin resistance in HepG2 cells, which was indicated by elevated phosphorylation of protein kinase B (AKT) and of glycogen synthase kinase-3 (GSK3ß). Furthermore, the expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase), two key gluconeogenic enzymes, were down-regulated following PRDX1 depletion. Accordingly, glucose uptake was suppressed in PRDX1-interferred HepG2 cells. In addition, Over-expression of PRDX1 enhanced PA-induced insulin resistance in HepG2 cells. Moreover, we found that knocking down PRDX1 improves insulin sensitivity and decreased the activation of p38 mitogen-activated protein kinase (p38MAPK). Our results demonstrate that PRDX1 can induce hepatic insulin resistance by activating p38MAPK signaling and identifies potential targets for new treatments.


Assuntos
Resistência à Insulina/fisiologia , Fígado/metabolismo , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Células Hep G2 , Humanos , Resistência à Insulina/genética , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Palmitatos/metabolismo , Peroxirredoxinas/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação para Cima
7.
Biochem Biophys Res Commun ; 463(1-2): 116-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26002461

RESUMO

Elevated free fatty acids (FFAs) are fundamental to the pathogenesis of hepatic insulin resistance. However, the molecular mechanisms of insulin resistance remain not completely understood. Transcriptional dysregulation, post-transcriptional modifications and protein degradation contribute to the pathogenesis of insulin resistance. Poly(C) binding proteins (PCBPs) are RNA-binding proteins that are involved in post-transcriptional control pathways. However, there are little studies about the roles of PCBPs in insulin resistance. PCBP2 is the member of the RNA-binding proteins and is thought to participate in regulating hypoxia inducible factor-1 (HIF-1α) and signal transducers and activators of transcription (STAT) pathway which are involved in regulating insulin signaling pathway. Here, we investigated the influence of PCBP2 on hepatic insulin resistance. We showed that the protein and mRNA levels of PCBP2 were down-regulated under insulin-resistant conditions. In addition, we showed that over-expression of PCBP2 ameliorates palmitate (PA)-induced insulin resistance, which was indicated by elevated phosphorylation of protein kinase B (AKT) and glycogen synthase kinase 3ß (GSK3ß). We also found that over-expression of PCBP2 inhibits HIF1α and STAT3 pathway. Furthermore, glucose uptake was found to display a similar tendency with the phosphorylation of Akt. The expressions of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase), two key gluconeogenic enzymes, were down-regulated following Over-expression of PCBP2. Accordingly, PA-induced intracellular lipid accumulation was suppressed in over-expression of PCBP2 HepG2 cells. In addition, we found that over-expression of PCBP2 inhibits HIF1α and STAT3 pathway. Our results demonstrate that PCBP2 was involved in hepatic insulin sensitivity might via HIF-1α and STAT3 pathway in HepG2 cells.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Resistência à Insulina/fisiologia , Proteínas de Ligação a RNA/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Regulação para Baixo , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células Hep G2 , Humanos , Resistência à Insulina/genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ácido Palmítico/farmacologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Transdução de Sinais
8.
Biochem Biophys Res Commun ; 457(4): 578-84, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25600807

RESUMO

Excess serum free fatty acids (FFAs) are fundamental to the pathogenesis of insulin resistance. Chronic endoplasmic reticulum (ER) stress is a major contributor to obesity-induced insulin resistance in the liver. With high-fat feeding (HFD), FFAs can activate chronic endoplasmic reticulum (ER) stress in target tissues, initiating negative crosstalk between FFAs and insulin signaling. However, the molecular link between insulin resistance and ER stress remains to be identified. We here reported that translocating chain-associated membrane protein 1 (TRAM1), an ER-resident membrane protein, was involved in the onset of insulin resistance in hepatocytes. TRAM1 was significantly up-regulated in insulin-resistant liver tissues and palmitate (PA)-treated HepG2 cells. In addition, we showed that depletion of TRAM1 led to hyperactivation of CHOP and GRP78, and the activation of downstream JNK pathway. Given the fact that the activation of ER stress played a facilitating role in insulin resistance, the phosphorylation of Akt and GSK-3ß was also analyzed. We found that depletion of TRAM1 markedly attenuated the phosphorylation of Akt and GSK-3ß in the cells. Moreover, application with JNK inhibitor SP600125 reversed the effect of TRAM1 interference on Akt phosphorylation. The accumulation of lipid droplets and expression of two key gluconeogenic enzymes, PEPCK and G6Pase, were also determined and found to display a similar tendency with the phosphorylation of Akt. Glucose uptake assay indicated that knocking down TRAM1 augmented PA-induced down-regulation of glucose uptake, and inhibition of JNK using SP600125 could block the effect of TRAM1 on glucose uptake. These data implicated that TRAM1 might protect HepG2 cells against PA-induced insulin resistance through alleviating ER stress.


Assuntos
Estresse do Retículo Endoplasmático , Células Hep G2/metabolismo , Resistência à Insulina , Sistema de Sinalização das MAP Quinases , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Palmitatos/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Chaperona BiP do Retículo Endoplasmático , Glucose/metabolismo , Humanos
9.
Gen Comp Endocrinol ; 224: 228-34, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26320856

RESUMO

Insulin resistance is often accompanied by chronic inflammatory responses. The mitogen-activated protein kinase (MAPK) pathway is rapidly activated in response to many inflammatory cytokines. But the functional role of MAPKs in palmitate-induced insulin resistance has yet to be clarified. In this study, we found that transforming growth factor ß-activated kinase binding protein-3 (TAB3) was up-regulated in insulin resistance. Considering the relationship between transforming growth factor ß-activated kinase (TAK1) and MAPK pathway, we assumed TAB3 involved in insulin resistance through activation of MAPK pathway. To certify this hypothesis, we knocked down TAB3 in palmitate treated HepG2 cells and detected subsequent biological responses. Importantly, TAB3 siRNA directly reversed insulin sensitivity by improving insulin signal transduction. Moreover, silencing of TAB3 could facilitate hepatic glucose uptake, reverse gluconeogenesis and improve ectopic fat accumulation. Meanwhile, we found that the positive effect of knocking down TAB3 was more significant when insulin resistance occurred. All these results indicate that TAB3 acts as a negative regulator in insulin resistance through activation of MAPK pathway.


Assuntos
Resistência à Insulina/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Western Blotting , Células Hep G2 , Humanos , Insulina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Fígado/citologia , MAP Quinase Quinase Quinases/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 3 Ativada por Mitógeno/genética , Ligação Proteica , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/genética
10.
Int J Mol Sci ; 16(9): 22856-69, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26402673

RESUMO

Protein tyrosine phosphatase 1B (PTP1B), which can directly dephosphorylate both the insulin receptor and insulin receptor substrate 1 (IRS-1), thereby terminating insulin signaling, reportedly plays an important role in insulin resistance. Accumulating evidence has demonstrated that O-GlcNAc modification regulates functions of several important components of insulin signal pathway. In this study, we identified that PTP1B is modified by O-GlcNAcylation at three O-GlcNAc sites (Ser104, Ser201, and Ser386). Palmitate acid (PA) impaired the insulin signaling, indicated by decreased phosphorylation of both serine/threonine-protein kinase B (Akt) and glycogen synthase kinase 3 beta (GSK3ß) following insulin administration, and upregulated PTP1B O-GlcNAcylation in HepG2 cells. Compared with the wild-type, intervention PTP1B O-GlcNAcylation by site-directed gene mutation inhibited PTP1B phosphatase activity, resulted in a higher level of phosphorylated Akt and GSK3ß, recovered insulin sensitivity, and improved lipid deposition in HepG2 cells. Taken together, our research showed that O-GlcNAcylation of PTP1B can influence insulin signal transduction by modulating its own phosphatase activity, which participates in the process of hepatic insulin resistance.


Assuntos
Acetilglucosamina/metabolismo , Fígado/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Acilação , Células Hep G2 , Humanos , Resistência à Insulina , Metabolismo dos Lipídeos
11.
Zhonghua Nei Ke Za Zhi ; 53(1): 9-12, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24674720

RESUMO

OBJECTIVE: To investigate the effects of a very low carbohydrate diet (VLCD) on improving cardiovascular risk factors in obese individuals. METHODS: A 8-week VLCD was given to 35 healthy obese subjects and the control group was consisted of 35 healthy volunteers. Multi-cardiovascular risk factors were investigated, including weight, waist circumference, BMI, blood pressure, fasting plasma glucose (FPG), fasting insulin (FIns), lipid profiles, urinary albumin-creatinine ratio (UACR), C-reactive protein (CRP) , TNFα and adiponectin. RESULTS: At the baseline of the study, compared with the healthy control group, all the cardiovascular risk factors were significantly more deteriorated in the obese subjects (all P values <0.05). At the end of the study, the obese subjects showed significant decrease in their mean weight and waist circumference [(8.5 ± 0.7) kg and (6.6 ± 1.1)cm, respectively; all P values < 0.01]. Significant decrease was also found in the levels of systolic blood pressure (SBP), diastolic blood pressure (DBP), FIns, TC and TG (all P values < 0.05), while no significant change of FPG, HDL-C and LDL-C. The levels of UACR, CRP and TNFα were all significantly decreased [(1.86 ± 0.86) µg/mg, (1.15 ± 0.45) mg/L and (0.94 ± 0.21) ng/L, respectively; all P values < 0.05], while the level of adiponectin was significantly increased [(2.12 ± 0.59) mg/L, P < 0.01]. CONCLUSION: VLCD is an effective intervention in obese subjects which could improve the cardiovascular risk factors by the modest weight loss.


Assuntos
Doenças Cardiovasculares/epidemiologia , Dieta com Restrição de Carboidratos , Obesidade/epidemiologia , Adulto , Glicemia/metabolismo , Peso Corporal , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/prevenção & controle , Estudos de Casos e Controles , Feminino , Humanos , Resistência à Insulina , Lipídeos/sangue , Masculino , Fatores de Risco
12.
Rheumatol Int ; 33(10): 2597-605, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23722874

RESUMO

We have recently reported that CD4(+) T cells synthesize and secrete catecholamines that facilitate a shift of T helper 1 (Th1)/Th2 balance toward Th2 polarization. In this study, we used an animal model of human rheumatoid arthritis, collagen type II-induced arthritis (CIA), to explore relationship between catecholamine production in CD4(+) T cells and Th1-/Th2-mediated joint inflammation. Histopathological observation of ankle joints of CIA mice displayed an evident inflammatory change on day 35 and a major damage to bones on day 55 post-immunization. Expression of Th1-specific transcription factor, T-bet, and cytokines, IL-2 and IFN-γ, and Th2-specific transcription factor, GATA-3, and cytokines, IL-4 and IL-10, was all upregulated on days 35 and 55 post-immunization, but the elevated Th1 response tended to decrease and the enhanced Th2 response tended to increase with the CIA progression. Expression of tyrosine hydroxylase (TH), a rate-limiting enzyme for synthesis of catecholamines, dramatically increased in ankle joints of CIA mice, although this increase was reduced on day 55 relative to that on day 35 post-immunization. In synovial tissue of CIA ankle joints but not normal joints, CD4-, T-bet-, GATA-3-, and TH-immunoreactive cells were found. Importantly, co-expressed cells with CD4 and TH, T-bet and TH, and GATA-3 and TH were observed in synovial tissue of CIA ankle joints. These results suggest that an increase in catecholamine production occurs in inflamed joints of CIA. The catecholamines are, at least in part, from Th1 and Th2 cells, and they may be related to joint inflammatory alleviation in CIA progression.


Assuntos
Articulação do Tornozelo/metabolismo , Artrite Experimental/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Articulação do Tornozelo/imunologia , Articulação do Tornozelo/patologia , Artrite Experimental/imunologia , Artrite Experimental/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Progressão da Doença , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos DBA , Membrana Sinovial/imunologia , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/patologia , Células Th2/imunologia , Células Th2/metabolismo , Células Th2/patologia
13.
Toxics ; 10(11)2022 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36355928

RESUMO

Urinary benzene metabolites trans, trans-muconic acid (t, t-MA), and S-phenyl mercapturic acid (S-PMA) are often used as biomarkers of internal exposure to benzene. However, there are few reports on using urinary benzene metabolites to estimate airborne benzene concentrations in individuals exposed to benzene. In this study, t, t-MA, and S-PMA were analyzed by UPLC-MS/MS, and a simple pharmacokinetic model was used to calculate the daily intake (DI) of benzene based on the levels of urinary t, t-MA, and S-PMA in occupational individuals. The back-calculated airborne benzene levels (BCABL) were obtained from the DI of benzene. Among the exposed subjects (n = 84), the median BCABL (3.67 mg/m3) based on t, t-MA was very close to the median level of measured airborne benzene (3.27 mg/m3, p = 0.171), and there was no effect of smoking or dietary habits on t, t-MA-based BCABL. In the control subjects (n = 49), the levels of measured airborne benzene were all below the quantitation limit (0.024 mg/m3), and the BCABL (0.002-0.25 mg/m3) calculated by S-PMA was close to this background level. Our study suggests that the t, t-MA-based BCABL can reflect the actual airborne benzene level in a range of 1.10-86.91 mg/m3 and that the S-PMA-based BCABL is more reliable for non-professional benzene exposure.

14.
Chemosphere ; 307(Pt 1): 135731, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35843426

RESUMO

The levels of legacy per- and polyfluoroalkyl substances (PFASs) have been growing in the environmental matrices and blood of residents living around the fluorochemical industrial park (FIP) in Fuxin of China over the past decade. Although some recent studies have reported occurrence of novel PFAS alternatives in biotic and abiotic matrices near fluorochemical facilities worldwide, little is known about novel PFAS congeners in maternal sera, umbilical cord sera, and placentas from the female residents close to the FIP and their related health risks. In this study, 50 paired samples of maternal and cord serum as well as placenta were derived from Fuxin pregnant women at delivery, and 21 target analytes of legacy PFASs in all the samples were analyzed via high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), revealing that PFBS, PFBA, and PFOA were the dominant PFAS contaminants observed in the whole samples. Based upon the suspect screening through high-resolution mass spectrometry (HRMS), 49 novel PFASs assigned to 11 classes were further identified in the Fuxin samples, of which, 20 novel congeners in 4 classes were reported in human blood and placentas for the first time. Moreover, the coefficients for mother-placenta transfer (Rm/p), placenta-newborn transfer (Rp/n), and mother-newborn transfer (Rm/n) of legacy PFASs could be calculated with median values of 1.7, 1.1, and 2.0, respectively, and Rm/p, Rp/n, and Rm/n for each novel PFAS identified were also estimated with the median values of 0.9, 1.2, and 0.8 individually. Accordingly, novel PFASs contributed 90% of all the legacy and novel PFASs in maternal sera and even occupied 96% of the whole PFASs in both placentas and cord sera. In addition, significant associations were determined among the neonate birth outcomes and serum concentrations of thyroid hormone, sex hormone, and glucocorticoid, together with the levels of certain legacy and novel PFASs in cord sera.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Ácidos Alcanossulfônicos/análise , China , Feminino , Fluorocarbonos/análise , Glucocorticoides , Humanos , Recém-Nascido , Placenta/química , Gravidez , Espectrometria de Massas em Tandem , Cordão Umbilical
15.
Diabetes Metab J ; 45(3): 404-416, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32794381

RESUMO

Background: Dysimmunity plays a key role in diabetes, especially type 1 diabetes mellitus. Islet-specific autoantibodies (ISAs) have been used as diagnostic markers for different phenotypic classifications of diabetes. This study was aimed to explore the relationships between ISA titers and the clinical characteristics of diabetic patients. Methods: A total of 509 diabetic patients admitted to Department of Endocrinology and Metabolism at the Affiliated Hospital of Nantong University were recruited. Anthropometric parameters, serum biochemical index, glycosylated hemoglobin, urinary microalbumin/creatinine ratio, ISAs, fat mass, and islet ß-cell function were measured. Multiple linear regression analysis was performed to identify relationships between ISA titers and clinical characteristics. Results: Compared with autoantibody negative group, blood pressure, weight, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), visceral fat mass, fasting C-peptide (FCP), 120 minutes C-peptide (120minCP) and area under C-peptide curve (AUCCP) of patients in either autoantibody positive or glutamate decarboxylase antibody (GADA) positive group were lower. Body mass index (BMI), waist circumference, triglycerides (TGs), body fat mass of patients in either autoantibody positive group were lower than autoantibody negative group. GADA titer negatively correlated with TC, LDL-C, FCP, 120minCP, and AUCCP. The islet cell antibody and insulin autoantibody titers both negatively correlated with body weight, BMI, TC, TG, and LDL-C. After adjusting confounders, multiple linear regression analysis showed that LDL-C and FCP negatively correlated with GADA titer. Conclusion: Diabetic patients with a high ISA titer, especially GADA titer, have worse islet ß-cell function, but less abdominal obesity and fewer features of the metabolic syndrome.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Síndrome Metabólica , Peptídeo C , Diabetes Mellitus Tipo 2/diagnóstico , Glutamato Descarboxilase , Humanos
16.
Diabetes Ther ; 12(9): 2437-2450, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34342864

RESUMO

INTRODUCTION: Delay in peak blood glucose during an oral glucose tolerance test (OGTT) predicts declining ß-cell function and poor ability to regulate glucose metabolism. Glucose peak time has not been used as a comparative indicator of the improvement in islet function after treatment with exenatide, insulin, or oral antidiabetic drugs (OADs). We evaluated the efficacy of three types of antidiabetic drugs on the basis of blood glucose peak time in patients with non-newly diagnosed type 2 diabetes. METHODS: The data from 100 patients with diabetes who completed two OGTTs within 6 months were collected. Thirty-seven of them with type 2 diabetes were treated with Humalog Mix25, 28 patients with OADs (metformin, acarbose, and gliclazide), and 35 patients with exenatide. RESULTS: Glycated hemoglobin improved in all three groups after treatment (P < 0.05). Subcutaneous adipose tissue (P < 0.01) and visceral adipose tissue (P < 0.0001) significantly decreased in the exenatide group. The insulinogenic index (IGI) (P = 0.01) and IGI × oral glucose insulin sensitivity (OGIS) (P = 0.01) improved in the exenatide group only. Homeostatic assessment of ß-cell function (HOMA-ß) and OGIS were greater in the exenatide and OAD groups than in the Humalog Mix25 group (all P < 0.05). A shift to an earlier peak was observed in 57.1%, 35.7%, and 27.0% of patients in the exenatide, OAD, and Humalog Mix25 groups, respectively (P = 0.029). OGIS (odds ratio [OR] 0.54, 95% confidence interval [CI] 0.33-0.89, P = 0.026) and IGI × OGIS (OR 1.72, 95% CI 0.44-6.68, P = 0.012) were independently related to shifts in glucose peak time. CONCLUSION: Exenatide, Humalog Mix25, and OADs improved glycemic metabolism. However, exenatide exhibited superior efficacy in shifting blood glucose peak time to an earlier point, while it improved insulin secretion and insulin sensitivity. Hence, the shift of glucose peak time may be considered an indicator for the evaluation of the effect of hypoglycemic drugs.

17.
Sci Rep ; 10(1): 8685, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457348

RESUMO

Extensive use of gallium arsenide (GaAs) has led to increased exposure to humans working in the semiconductor industry. This study employed physicochemical characterization of GaAs obtained from a workplace, cytotoxicity analysis of damage induced by GaAs in 16HBE cells, RNA-seq and related bioinformatic analysis, qRT-PCR verification and survival analysis to comprehensively understand the potential mechanism leading to lung toxicity induced by GaAs. We found that GaAs-induced abnormal gene expression was mainly related to the cellular response to chemical stimuli, the regulation of signalling, cell differentiation and the cell cycle, which are involved in transcriptional misregulation in cancer, the MAPK signalling pathway, the TGF-ß signalling pathway and pulmonary disease-related pathways. Ten upregulated genes (FOS, JUN, HSP90AA1, CDKN1A, ESR1, MYC, RAC1, CTNNB1, MAPK8 and FOXO1) and 7 downregulated genes (TP53, AKT1, NFKB1, SMAD3, CDK1, E2F1 and PLK1) related to GaAs-induced pulmonary toxicity were identified. High expression of HSP90AA1, RAC1 and CDKN1A was significantly associated with a lower rate of overall survival in lung cancers. The results of this study indicate that GaAs-associated toxicities affected the misregulation of oncogenes and tumour suppressing genes, activation of the TGF-ß/MAPK pathway, and regulation of cell differentiation and the cell cycle. These results help to elucidate the molecular mechanism underlying GaAs-induced pulmonary injury.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Gálio/toxicidade , RNA/metabolismo , Regulação para Cima/efeitos dos fármacos , Arsenicais , Brônquios/citologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epitelioides/citologia , Células Epitelioides/efeitos dos fármacos , Células Epitelioides/metabolismo , Humanos , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Mapas de Interação de Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , RNA/química , Análise de Sequência de RNA , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
18.
Biomed Res Int ; 2020: 1751989, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104677

RESUMO

PURPOSE: Type 2 diabetes mellitus (T2DM) carries a high risk of hepatocellular carcinoma (HCC). Both serum fibroblast growth factor 19 (FGF19) and bile acid concentrations are associated with T2DM and HCC. We aimed at evaluating the relationships between FGF19 and bile acid concentrations and HCC in patients with T2DM. METHODS: Twenty-seven healthy volunteers (control group), 27 patients with T2DM (T2DM group), 16 patients with newly diagnosed HCC (HCC group), and 10 T2DM patients with newly diagnosed HCC (T2DM-HCC group) were studied at the Affiliated Hospital of Nantong University between June 2016 and June 2017. The serum concentrations of serum FGF19 and total bile acids (TBA) were measured in all the participants. Correlation analysis and multiple stepwise regression analysis of the FGF19 and TBA concentrations were performed in all the participants and in the four groups. RESULTS: The concentrations of FGF19 were 220.5 pg/ml, 185.1 pg/ml, 115.8 pg/ml, and 70.4 pg/ml in the HCC, T2DM-HCC, control, and T2DM groups, respectively (p < 0.001), and the TBA concentrations were 21.75 µmol/l, 14.25 µmol/l, 14.25 µmol/l, 14.25 µmol/l, 14.25 p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 r = 0.777; p < 0.001), and the TBA concentrations were 21.75 . CONCLUSIONS: Simultaneous increase of serum FGF19 and TBA levels may be used as indicators of HCC screening at early stage in patients with T2DM.


Assuntos
Ácidos e Sais Biliares/metabolismo , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Diabetes Mellitus Tipo 2/sangue , Fatores de Crescimento de Fibroblastos/sangue , Neoplasias Hepáticas/sangue , Proteínas de Neoplasias/sangue , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade
19.
J Diabetes Res ; 2020: 9783859, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32566685

RESUMO

In China, most normal BMI (body mass index of ≥18.5 to <25 kg/m2) adults with type 2 diabetes (T2DM) exhibit visceral adiposity. This study compared the effects of exenatide and humalog Mix25 on normal BMI patients with T2DM and visceral adiposity. A total of 95 patients were randomized to receive either exenatide or humalog Mix25 treatment for 24 weeks. Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were quantified by magnetic resonance imaging (MRI) and liver fat content (LFC) by liver proton magnetic resonance spectroscopy (1H MRS). Each patient's weight, waist circumference, BMI, blood glucose, insulin sensitivity, pancreatic ß-cell function, and fibroblast growth factor 21 (FGF-21) levels were measured. Data from 81 patients who completed the study (40 and 41 in the exenatide and humalog Mix25 groups, respectively) were analysed. The change in 2 h plasma blood glucose was greater in the exenatide group (P = 0.039). HOMA-IR and MBCI improved significantly after exenatide therapy (P < 0.01, P = 0.045). VAT and LFC decreased in both groups (P < 0.01 for all) but to a greater extent in the exenatide group, while SAT only decreased with exenatide therapy (P < 0.01). FGF-21 levels declined more in the exenatide group (P < 0.01), but were positively correlated with VAT in the entire cohort before (r = 0.244, P = 0.043) and after (r = 0.290, P = 0.016) the intervention. The effects of exenatide on glycaemic metabolism, insulin resistance, pancreatic ß-cell function, and fat deposition support its administration to normal BMI patients with T2DM and visceral adiposity.


Assuntos
Insulinas Bifásicas/farmacologia , Distribuição da Gordura Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Exenatida/farmacologia , Insulina Lispro/farmacologia , Resistência à Insulina , Insulina Isófana/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Obesidade Abdominal/tratamento farmacológico , Adiposidade/efeitos dos fármacos , Adiposidade/fisiologia , Adulto , Idoso , Insulinas Bifásicas/administração & dosagem , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Exenatida/administração & dosagem , Feminino , Humanos , Insulina Lispro/administração & dosagem , Insulina Isófana/administração & dosagem , Células Secretoras de Insulina/fisiologia , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/complicações , Obesidade Abdominal/metabolismo , Resultado do Tratamento
20.
J Diabetes Investig ; 9(6): 1288-1295, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29537733

RESUMO

AIMS/INTRODUCTION: Previous studies have shown that glucose peak time during the oral glucose tolerance test varies in type 2 diabetes patients; however, characteristics of this heterogeneity remain unclear. This research aimed to investigate the characteristics of delayed glucose peak time in type 2 diabetes. MATERIALS AND METHODS: A total of 178 participants who underwent the oral glucose tolerance test were divided into five groups according to glucose peak time. RESULTS: A total of 25 participants with normal glucose tolerance had a glucose peak at 30 min. Among participants with type 2 diabetes, 28 had a glucose peak at 60 min, 48 at 90 min, 45 at 120 min and 32 at 150 min. With the glucose peak time delayed, glycated hemoglobin, area under the glucose curve and homeostatic model assessment of insulin resistance increased gradually (P = 0.038, P < 0.0001, P < 0.0001, respectively), and oral glucose insulin sensitivity, homeostatic model assessment of ß-cell function, insulinogenic index, modified ß-cell function index and disposition indices decreased (P < 0.0001 for all). On multinominal logistic regression, insulinogenic index (odds ratio 0.73, 95% confidence interval 0.57-0.93, P = 0.01), modified ß-cell function index (odds ratio 0.67, 95% confidence interval 0.47-0.94, P = 0.023) and oral glucose insulin sensitivity (odds ratio 0.91, 95% confidence interval 0.87-0.96, P < 0.0001) were independently correlated with delayed glucose peak time. CONCLUSIONS: Delay in glucose peak time indicated an increase in blood glucose and a decrease in insulin sensitivity and secretion. Furthermore, insulinogenic index, modified ß-cell function index and oral glucose insulin sensitivity contributed to delayed glucose peak time.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/metabolismo , Teste de Tolerância a Glucose , Resistência à Insulina , Secreção de Insulina , Peptídeo C/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade
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