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1.
Int J Biol Macromol ; 241: 124638, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37119889

RESUMO

Propylene glycol alginate sodium sulfate (PSS) is a heparinoid polysaccharide drug used in clinic for >30 years in China. But its allergy events happened from time to time and should not be ignored. Here, ammonium salt in PSS (PSS-NH4+), PSS fractions with high Mw (PSS-H-Mw) and low mannuronic acid (M) to guluronic acid (G) ratio (PSS-L-M/G) were found to induce allergic response by the structure-activity and impurity-activity relationships in vitro. Furthermore, we confirmed the reason and elucidated the mechanism accounted for allergic side effect of PSS in vivo. It was found that high IgE levels in PSS-NH4+ and PSS-H-Mw groups upregulate the cascade expression of Lyn-Syk-Akt or Erk and second messenger Ca2+, which accelerated mast cells (MCs) degranulation to release histamine, LTB4, TPS, and finally induced lung tissue injury. PSS-L-M/G caused a mild allergic symptom because it only enhanced the expression of p-Lyn and histamine release. In brief, PSS-NH4+ and PSS-H-Mw were main reasons to result in allergic response. Our results suggested that it is very necessary to control the range of Mw and the content of impurities (< 1 % ammonium salt) of PSS to guarantee its safety and effectiveness in clinical treatment.


Assuntos
Compostos de Amônio , Hipersensibilidade , Humanos , Alginatos/farmacologia , Polissacarídeos/farmacologia , Hipersensibilidade/tratamento farmacológico , Mastócitos
2.
Genes Dis ; 9(1): 51-61, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35005107

RESUMO

The goal this review is to clarify the effects of the fat mass and obesity-associated protein (FTO) in lipid metabolism regulation and related underlying mechanisms through the FTO-mediated demethylation of m6A modification. FTO catalyzes the demethylation of m6A to alter the processing, maturation and translation of the mRNAs of lipid-related genes. FTO overexpression in the liver promotes lipogenesis and lipid droplet (LD) enlargement and suppresses CPT-1-mediated fatty acid oxidation via the SREBP1c pathway, promoting excessive lipid storage and nonalcoholic fatty liver diseases (NAFLD). FTO enhances preadipocyte differentiation through the C/EBPß pathway, and facilitates adipogenesis and fat deposition by altering the alternative splicing of RUNX1T1, the expression of PPARγ and ANGPTL4, and the phosphorylation of PLIN1, whereas it inhibits lipolysis by inhibiting IRX3 expression and the leptin pathway, causing the occurrence and development of obesity. Suppression of the PPARß/δ and AMPK pathways by FTO-mediated m6A demethylation damages lipid utilization in skeletal muscles, leading to the occurrence of diabetic hyperlipidemia. m6A demethylation by FTO inhibits macrophage lipid influx by downregulating PPARγ protein expression and accelerates cholesterol efflux by phosphorylating AMPK, thereby impeding foam cell formation and atherosclerosis development. In summary, FTO-mediated m6A demethylation modulates the expression of lipid-related genes to regulate lipid metabolism and lipid disorder diseases.

3.
BMC Complement Med Ther ; 20(1): 243, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32758223

RESUMO

BACKGROUND: Lung cancer has the highest morbidity and mortality in the world and novel treatment strategies are still needed. Haimufang decoction (HMF) is a patented clinical prescription of traditional Chinese medicine for lung cancer treatment. HMF is composed of four herbs and has been applied clinically in advanced cancer patients. However, its therapeutic mechanisms are still unclear. This study aims to elucidate the possible mechanisms of HMF for the treatment of lung cancer. METHODS: 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay was applied for evaluating the proliferative effect of HMF in lung cancer cells and monocyte macrophage RAW264.7 cells. Flow cytometer was used to detect the effects of HMF on cell cycle and apoptosis, and western blotting was employed to explore the potential apoptotic mechanisms of HMF on lung cancer cells. For immunomodulatory effect, co-culture system was used to detect the activation of macrophage RAW264.7 cells when treated with HMF, and neutral red assay was used to measure the effect of HMF on the phagocytosis of the activated macrophages. Enzyme linked immunosorbent assay, flow cytometer, and immunofluorescence staining method were employed for the investigation on the underlying mechanisms of the immunomodulatory effect on RAW264.7 induced by HMF. RESULTS: HMF inhibited the proliferation, induced S phase cell cycle arrest, and stimulated apoptosis in lung cancer NCI-H1975 cells, while had negligible cytotoxicity on macrophage RAW264.7 cells. Moreover, HMF could activate macrophage RAW264.7 cells and promote the inhibition activity of RAW264.7 cells against lung cancer cells. And also, HMF activated macrophages and increased their phagocytic activity in a concentration-dependent manner. HMF increased the expression of macrophage activation marker CD40, the level of nitric oxide, the generation of intracellular reactive oxygen species, as well as M1 macrophages cytokines including tumor necrosis factor-α, interleukin-1ß, interleukin 12 p70, and interleukin 6. Further investigation showed that HMF induced M1 but not M2 phenotype polarization in RAW264.7 cells. CONCLUSIONS: HMF can mainly exert anticancer activity via (1) cytotoxicity to human lung cancer cells by proliferation inhibition, cell cycle arrest, and apoptosis induction; and also via (2) immunomodulation via macrophage cells activation and M1 phenotype polarization induction.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Células RAW 264.7
4.
Carbohydr Polym ; 194: 365-374, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29801851

RESUMO

Propylene glycol alginate sodium sulfate (PSS), a sulfated polysaccharide derivative, has been used as a heparinoid drug to prevent and treat hyperlipidemia and ischemic cardio-cerebrovascular diseases in China for 30 years. But its bleeding risk should not be overlooked. Here we clarified the reasons and mechanism leading to bleeding side effect of PSS. It was found that PSS fractions with low mannuronic acid (M)/guluronic acid (G) ratio and high molecular weight (Mw) can excessively extend activated partial thromboplastin time (APTT) and thrombin time (TT), over-inhibit the thrombin (FIIa) activity mediated by anti-thrombin III (ATIII) to induce bleeding risk. In addition, the fraction of low M/G ratio can suppress platelet aggregation mediated by adenosine diphosphate (ADP) and induce platelet reduction by improving platelet antibody (PA)-IgA/G in serum and by inhibiting or damaging the bone marrow hematopoietic function. And the fraction of high Mw can restrain the reticulated platelet (RP) production, then reduce mean platelet volume (MPV) and platelet-large cell counts or ratio, and finally decrease platelet amount by inhibiting or damaging the bone marrow hematopoietic function. In brief, PSS fractions with low M/G ratio and high Mw were the main reasons to bring about bleeding by excessively suppressing coagulant factors activities and weakening platelet function. Our results suggested that it is very necessary to control the M/G ratio and the range of Mw of PSS to guarantee its safety and effectiveness in clinical.


Assuntos
Alginatos/efeitos adversos , Anticoagulantes/efeitos adversos , Hemorragia/tratamento farmacológico , Polissacarídeos/efeitos adversos , Sulfatos/efeitos adversos , Alginatos/química , Alginatos/farmacologia , Animais , Anticoagulantes/química , Anticoagulantes/farmacologia , Testes de Coagulação Sanguínea , Configuração de Carboidratos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos , Agregação Plaquetária/efeitos dos fármacos , Polissacarídeos/química , Polissacarídeos/farmacologia , Ratos , Ratos Wistar , Sulfatos/química , Sulfatos/farmacologia
5.
Carbohydr Polym ; 144: 330-7, 2016 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-27083824

RESUMO

The combination of biological and chemical analysis methods was developed to improve quality control of propylene glycol alginate sodium sulfate (PSS), a sulfated polysaccharide drug. The allergic and anticoagulant assays revealed that PSS fractions with higher Mw and lower M/G ratio may have allergic response and bleeding risks. HPLC with pre-column derivatization, HPGPC and IC methods were combined to analyze 10 batches of PSS samples from different manufacturers. The results showed that the quality of these PSSs varied greatly which in turn led to the unstable anticoagulant activity and side effects. The study indicated that PSS with high purity, M/G ratio above 1.5, Mw of ∼9kD and DS of 9.0-13.0% can ensure clinical efficacy and low incidence of adverse drug reactions. In conclusion, the combined methods would be in favor of guiding manufacture and quality control of PSS to guarantee its effectiveness and safety.


Assuntos
Alginatos/química , Anticoagulantes/química , Polissacarídeos/química , Alginatos/farmacologia , Animais , Anticoagulantes/farmacologia , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Humanos , Hipersensibilidade/etiologia , Camundongos , Peso Molecular , Polissacarídeos/farmacologia , Controle de Qualidade , Enxofre/química
6.
Food Funct ; 6(9): 3056-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26205038

RESUMO

Muscle wasting is associated with a variety of chronic or inflammatory disorders. Evidence suggests that inflammatory cytokines play a vital role in muscle inflammatory pathology and this may result in oxidative damage and mitochondrial dysfunction in skeletal muscle. In our study, we used microwave degradation to prepare a water-soluble low molecular weight guluronate (LMG) of 3000 Da from Fucus vesiculosus obtained from Canada, the Atlantic Ocean. We demonstrated the structural characteristics, using HPLC, FTIR and NMR of LMG and investigated its effects on oxidative damage and mitochondrial dysfunction in C2C12 skeletal muscle cells induced by tumor necrosis factor alpha (TNF-α), a cell inflammatory cytokine. The results indicated that LMG could alleviate mitochondrial reactive oxygen species (ROS) production, increase the activities of antioxidant enzymes (GSH and SOD), promote mitochondrial membrane potential (MMP) and upregulate the expression of mitochondrial respiratory chain protein in TNF-α-induced C2C12 cells. LMG supplement also increased the mitochondrial DNA copy number and mitochondrial biogenesis related genes in TNF-α-induced C2C12 cells. LMG may exert these protective effects through the nuclear factor kappa B (NF-κB) signaling pathway. These suggest that LMG is capable of protecting TNF-α-induced C2C12 cells against oxidative damage and mitochondrial dysfunction.


Assuntos
Caquexia/metabolismo , Fucus/química , Ácidos Hexurônicos/farmacologia , Mitocôndrias/efeitos dos fármacos , Células Musculares/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Animais , Caquexia/tratamento farmacológico , Caquexia/enzimologia , Linhagem Celular , Glutationa/metabolismo , Ácidos Hexurônicos/química , Humanos , Camundongos , Mitocôndrias/metabolismo , Peso Molecular , Células Musculares/enzimologia , Células Musculares/metabolismo , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Alga Marinha/química , Superóxido Dismutase/metabolismo
7.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-250334

RESUMO

Bone marrow mesenchymal stem cells (MSCs) transplantation could repair injury tissue, but no study confirms whether MSCs can promote the proliferation of endogenous lung stem cells to repair alveolar epithelial cells of mice with chronic obstructive pulmonary disease (COPD). This study was designed to investigate the effect of MSCs on the proliferation of endogenous lung stem cells in COPD mice to confirm the repair mechanism of MSCs. The mice were divided into control group, COPD group, and COPD+MSCs group. The following indexes were detected: HE staining of lung tissue, the mean linear intercept (MLI) and alveolar destructive index (DI), the total cell number in bronchoalveolar lavage fluid (BALF), pulmonary function, alveolar wall apoptosis index (AI) and proliferation index (PI), the number of CD45(-)/CD31(-)/Sca-1(+) cells by flow cytometry (FCM), and the number of bronchoalveolar stem cells (BASCs) in bronchoalveolar duct junction (BADJ) by immunofluorescence. As compared with control group, the number of inflammatory cells in lung tissue was increased, alveolar septa was destroyed and the emphysema-like changes were seen, and the changes of lung function were in line with COPD in COPD group; AI of alveolar wall was significantly increased and PI significantly decreased in COPD group. There was no significant difference in the number of CD45(-)/CD31(-)/Sca-1(+) cells and BASCs between control group and COPD group. As compared with COPD group, the number of inflammatory cells in BALF was decreased, the number of CD45(-)/CD31(-)/Sca-1(+) cells and BASCs was increased, AI of alveolar wall was decreased and PI was increased, and emphysema-like changes were relieved in COPD+MSCs group. These findings suggested that MSCs transplantation can relieve lung injury by promoting proliferation of endogenous lung stem cells in the cigarette smoke-induced COPD mice.


Assuntos
Animais , Camundongos , Proliferação de Células , Pulmão , Patologia , Células-Tronco Mesenquimais , Biologia Celular , Camundongos Endogâmicos C57BL , Doença Pulmonar Obstrutiva Crônica , Patologia , Terapêutica
8.
Yao Xue Xue Bao ; 49(7): 1049-53, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25233639

RESUMO

The fine structure of enoxaparin sodium samples with different degree of 1,6-anhydro derivatives were analyzed with polyacrylamide gel electrophoresis, high performance liquid chromatography, ultraviolet spectroscopy, infrared spectroscopy and nuclear magnetic resonance spectroscopy. A further study of anticoagulation activity of enoxaparins was performed, including those on their inhibition activities of coagulation factor Xa (FXa) and thrombin (FIIa). The results showed that the anti-FXa and -FIIa activities of enoxaparins with different degree of 1,6-anhydro derivatives (20.0%-39.7%) with similar structure characteristics, had decreasing tendency when the degree of 1,6-anhydro derivatives increased. Especially, the anti-FXa activity was sensitive to the change of the degree of 1,6-anhydro derivatives.


Assuntos
Anticoagulantes/química , Enoxaparina/química , Inibidores do Fator Xa/química , Trombina/antagonistas & inibidores
9.
Eur J Med Chem ; 85: 304-10, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25089813

RESUMO

Low molecular weight and sulfated low molecular weight guluronate (LMG and SLMG) were prepared and hypolipidemic effects were studied in a human hepatocellular carcinoma HepG2 cell line. Both compounds decreased total cholesterol (TC) and triglycerides (TG) and inhibited 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) activity in HepG2 cells. In general, SLMG had greater effects than LMG. Activation of sterol regulatory element-binding protein 2 (SREBP-2), low density lipoprotein receptor (LDLR), AMP-activated protein kinase (AMPK), and AMPK's downstream targets were evidenced by increased phosphorylation of AMPK, HMGCR, and acetyl-CoA-carboxylase (ACC), which decreased HMGRC and ACC activity. We further demonstrated that activated AMPK was linked to down-regulated SREBP-1 and up-regulated cholesterol 7α-hydroxylase (CYP7A1).


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ácidos Hexurônicos/química , Ácidos Hexurônicos/farmacologia , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Sulfatos/química , Acetil-CoA Carboxilase/metabolismo , Proliferação de Células/efeitos dos fármacos , Colesterol/metabolismo , Colesterol 7-alfa-Hidroxilase/metabolismo , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Ácidos Graxos/metabolismo , Células Hep G2 , Humanos , Hidroximetilglutaril-CoA Redutases/metabolismo , Peso Molecular , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Receptores de LDL/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Triglicerídeos/metabolismo
10.
Mar Drugs ; 11(4): 1113-25, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23549283

RESUMO

This study was aimed at developing a sensitive and selective HPLC method with postcolumn fluorescence derivatization for the detection of propylene glycol alginate sodium sulfate (PSS) in rat plasma. Plasma samples were prepared by a simple and fast ultrafiltration method. PSS was extracted from rat plasma with D-glucuronic acid as internal standard. Isocratic chromatographic separation was performed on a TSKgel G2500 PWxL column with the mobile phase of 0.1 M sodium sulfate at a flow rate of 0.5 mL/min. Analyte detection was achieved by fluorescence detection (FLD) at 250 nm (excitation) and 435 nm (emission) using guanidine hydrochloride as postcolumn derivatizing reagent in an alkaline medium at 120 °C. The calibration curve was linear over a concentration range of 1-500 µg/mL, and the lower limit of detection (LLOD) was found to be 250 ng/mL. This validated method was applied successfully to the pharmacokinetic study of PSS and PSS-loaded poly lactic-co-glycolic acid (PLGA) nanoparticles (PSS-NP) in rat plasma after a single intravenous (PSS only) and oral administration (PSS and PSS-NP). Significant differences in the main pharmacokinetic parameters of PSS and PSS-NP were observed. The relative bioavailability of PSS-NP was 190.10% compared with PSS which shows that PSS-NP can improve oral bioavailability.


Assuntos
Alginatos/farmacocinética , Cromatografia Líquida de Alta Pressão/métodos , Ácido Láctico/química , Nanopartículas , Ácido Poliglicólico/química , Administração Oral , Alginatos/análise , Alginatos/química , Animais , Disponibilidade Biológica , Calibragem , Feminino , Fluorescência , Injeções Intravenosas , Limite de Detecção , Masculino , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Wistar , Sulfatos/química
11.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-243205

RESUMO

With the development of genome-wide sequencing technology, 195 types of functional long non-coding RNAs (lncRNAs) have so far been found, and their cellular roles are gradually being revealed. Now lncRNAs have become a hotspot in the life science. These small molecules exist in almost all higher eukaryotes, and have very important regulatory roles in these organisms. This review briefly summarizes recent progress in researches on antisense non-coding RNA in the INK4 locus.


Assuntos
Animais , Humanos , Proteínas Inibidoras de Quinase Dependente de Ciclina , Genética , Loci Gênicos , RNA Antissenso , Fisiologia , RNA Longo não Codificante , Fisiologia
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-266098

RESUMO

<p><b>OBJECTIVE</b>This study aims to investigate the bacteria contamination on hands of funeral staffs in different positions.</p><p><b>METHODS</b>Bacterial samples were collected from the hands of 105 funeral staffs in different positions (including 90 frontline staffs and 15 administrative workers) from 13 funeral parlors nationwide, and were subsequently tested by bacterium inspection.</p><p><b>RESULTS</b>In total, 1783 strains of bacteria were isolated, including 1027 Gram-positive bacteria, most of which were Staphylococcus; and 756 Gram-negative bacteria, most of which were Pseudomonas. Out of the 1783 strains of bacteria, 570 pathogens and opportunistic pathogens were isolated, accounted to 31.96%. The isolated ratio of pathogens and conditional pathogens in embalmed/cosmetologist of cadavers was 35.67% (370/1037), which was higher than those in the funeral workers in other positions, such as cremators, pick-up and administrative workers, whose ratios were 24.42% (95/389), 22.41% (52/232) and 10.40% (12/125), respectively (χ(2) were 13.682, 10.967 and 32.263, respectively; P values were all < 0.05). And the isolated ratios of pathogens and conditional pathogens in cremators and pick-up workers were significantly higher than that in administrative workers (χ(2) were 11.206 and 7.873, respectively; P values were all < 0.05).</p><p><b>CONCLUSION</b>Lots of bacteria were found in the samples from hands of funeral staffs. The isolated ratio of pathogens and conditional pathogens was different between the funeral staffs in different positions; while the highest was from embalmed/cosmetologist of cadavers and the lowest was from administrators.</p>


Assuntos
Humanos , Bactérias , Mãos , Microbiologia , Testes de Sensibilidade Microbiana , Práticas Mortuárias , Exposição Ocupacional
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(9): 2484-7, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-21105423

RESUMO

Glycosaminoglycans (GAGs) were extracted and purified from Wistar rat kidneys by two-step enzymatic hydrolysis and ion exchange chromatography. The sorts of GAGs were identified by electrophoresis on cellulose acetate membrane and separated on a weak anion-exchange column. Those purified GAGs were further totally hydrolyzed with specific glycosaminoglycan lyases. Their disaccharides composition and fine structures were analyzed with SAX-HPLC. The results indicated that GAGs in rat kidneys were mainly composed of heparan sulfate and small amount of dermatan sulfate. Eight kinds of disaccharides were found in heparan sulfate, and the content of acetyl-containing disaccharides was 77.6%, while nonsulfated disaccharides were 59.7%. In dermatan sulfate, six kinds of disaccharides were found. The content of monosulfated disaccharides was 49.8%, and nonsulfated disaccharides were 32.9%.


Assuntos
Glicosaminoglicanos/química , Rim/química , Animais , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Dermatan Sulfato/química , Dissacarídeos/química , Eletroforese , Ratos , Ratos Wistar
14.
Asian Journal of Andrology ; (6): 266-271, 2009.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-284688

RESUMO

We have observed earlier that testosterone at physiological concentrations can stimulate tissue factor pathway inhibitor (TFPI) gene expression through the androgen receptor in endothelial cells. This study further investigated the impact of testosterone on TFPI levels in response to inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha). Cultured human umbilical vein endothelial cells were incubated in the presence or absence of testosterone or TNF-alpha. TFPI protein and mRNA levels were assessed by enzyme-linked immunosorbent assay and quantitative real-time reverse transcription polymerase chain reaction. To study the cellular mechanism of testosterone's action, nuclear factor-kappa B (NF-kappaB) translocation was confirmed by electrophoretic mobility shift assays. We found that after NF-kappaB was activated by TNF-alpha, TFPI protein levels declined significantly by 37.3% compared with controls (P < 0.001), and the mRNA levels of TFPI also decreased greatly (P < 0.001). A concentration of 30 nmol L(-1) testosterone increased the secretion of TFPI compared with the TNF-alpha-treated group. NF-kappaB DNA-binding activity was significantly suppressed by testosterone (P < 0.05). This suggests that physiological testosterone concentrations may exert their antithrombotic effects on TFPI expression during inflammation by downregulating NF-kappaB activity.


Assuntos
Humanos , Recém-Nascido , Androgênios , Farmacologia , Células Cultivadas , Regulação para Baixo , Combinação de Medicamentos , Endotélio Vascular , Metabolismo , Lipoproteínas , Genética , Metabolismo , Subunidade p50 de NF-kappa B , Genética , RNA Mensageiro , Metabolismo , Testosterona , Farmacologia , Fator de Necrose Tumoral alfa , Farmacologia
15.
Chinese Medical Journal ; (24): 241-247, 2008.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-255728

RESUMO

<p><b>BACKGROUND</b>Under an insulin resistance (IR) state, overproduction of reactive oxygen species (ROS) may be playing a major role in the pathogenesis of endothelial dysfunction, hypertension and atherosclerosis. Recently, increasing attention has been drawn to the beneficial effects of heme oxygenase-1 (HO-1) in the cardiovascular system. This study aimed to investigate the effects of HO-1 on vascular function of thoracic aorta in IR rats and demonstrate the probable mechanisms of HO-1 against endothelial dysfunction in IR states.</p><p><b>METHODS</b>Sprague-Dawley (SD) rats fed with high-fat diet for 6 weeks and the IR models were validated with hyperinsulinemic-euglycemic clamp test. Then the IR rat models (n = 44) were further randomized into 3 subgroups, namely, the IR control group (n = 26, in which 12 were sacrificed immediately and evaluated for all study measures), a hemin treated IR group (n = 10) and a zinc protoporphyrin-IX (ZnPP-IX) treated IR group (n = 8) that were fed with a high-fat diet. Rats with standardized chow diet were used as the normal control group (n = 12). The rats in IR control group, hemin treated IR group and ZnPP-IX treated IR group were subsequently treated every other day with an intraperitoneal injection of normal saline, hemin (inducer of HO-1, 30 micromol/kg) or ZnPP-IX (inhibitor of HO-1, 10 micromol/kg) for 4 weeks. Rats in the normal control group remained on a standardized chow diet and were treated with intraperitoneal injections of normal saline every other day for 4 weeks. Systolic arterial blood pressure (SABP) was measured by tail-cuffed microphotoelectric plethysmography. The blood carbon monoxide (CO) was measured by blood gas analysis. The levels of nitric oxide (NO), inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), blood glucose (BG), insulin, total cholesterol (TC) and triglyceride (TG) in serum, and the levels of total antioxidant capacity (TAOC), malondialdehyde (MDA) and superoxide dismutase (SOD) in the aorta were measured. The expression of HO-1 mRNA and HO-1 protein in aortal tissue were detected by semi-quantitative RT-PCR and Western blot. The vasoreactive tensometry was performed with thoracic aortic rings (TARs).</p><p><b>RESULTS</b>Compared with the normal control group, the levels of SABP, BG, insulin, TC, TG, NO, iNOS and MDA were higher, while the levels of CO, TAOC, SOD and eNOS were lower in IR control rats. After treatment of IR rats for 4 weeks a more intensive expression of HO-1 mRNA and HO-1 protein were observed in hemin treated IR group compared with the normal control group. And compared with 4-week IR control rats, the levels of CO, TAOC, SOD and eNOS were increased, while the levels of SABP and iNOS activity were lower in the hemin treated IR group. Administration of hemin in IR rats appeared to improve the disordered vasorelaxation of TARs to acetylcholine (ACh). Alternatively, the reverse results of SABP, CO, TAOC, SOD, iNOS and vasorelaxation responses to ACh were observed in IR rats with administration of ZnPP-IX.</p><p><b>CONCLUSIONS</b>The endothelial dysfunction in the aorta is present in the IR state. The protective effects of HO-1 against aortic endothelial dysfunction may be due to its antioxidation and regulative effect of vasoactive substances. It is proposed that hemin, inducer of HO-1, could be a potential therapeutic option for vascular dysfunction in IR states.</p>


Assuntos
Animais , Masculino , Ratos , Aorta , Fisiologia , Monóxido de Carbono , Sangue , Endotélio Vascular , Fisiologia , Indução Enzimática , Heme Oxigenase-1 , Genética , Hemina , Farmacologia , Resistência à Insulina , Óxido Nítrico , Sangue , Estresse Oxidativo , Ratos Sprague-Dawley , Sístole
16.
National Journal of Andrology ; (12): 777-779, 2007.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-232066

RESUMO

<p><b>OBJECTIVE</b>To investigate the effects of testosterone on extracellular signal-regulated kinase l/2 ( ERK1/2) phosphorylation in human umbilical vein endothelial cells (HUVEC).</p><p><b>METHODS</b>Activations of ERK1/2 stimulated by physiological testosterone were detected by Western blotting in cultured HUVEC.</p><p><b>RESULTS</b>A rapid phosphorylation expression of ERK1/2 was observed by treatment of the HUVECs with 3 x 10(-8) mol/L testosterone, especially at 30 minutes. This phosphorylation was greatly inhibited by incubation with androgen receptor antagonist flutamide for 3 hours previously.</p><p><b>CONCLUSION</b>Testosterone at physiological concentrations induces the mitogen-activated protein kinase (MAPK, ERK1/2 and MEK1/2) phosphorylation within a short time, and flutamide could impair the process.</p>


Assuntos
Humanos , Antagonistas de Receptores de Andrógenos , Western Blotting , Células Cultivadas , Células Endoteliais , Biologia Celular , Metabolismo , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular , Metabolismo , Proteína Quinase 1 Ativada por Mitógeno , Metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Metabolismo , Fosforilação , Receptores Androgênicos , Metabolismo , Testosterona , Farmacologia , Veias Umbilicais , Biologia Celular
17.
Acta Biochim Biophys Sin (Shanghai) ; 38(9): 633-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16953302

RESUMO

Extracellular alginate lyase secreted by marine Vibrio sp. YWA, isolated from decayed Laminaria japonica, was purified by a combination of ammonium sulfate precipitation and diethylaminoethyl-Sephacel column chromatography. The results show that the molecular mass of alginate lyase was approximately 62.5 kDa, with an optimal pH and temperature at pH 7.0 and 25 degrees C, respectively. K(m) was approximately 72.73 g/L. The activity of the enzyme was enhanced by EDTA and Zn(2+), but inhibited by Ba(2+). The substrates specificity analysis shows that it was specific for hydrolyzing poly-beta-D-1,4-mannuronate in alginate.


Assuntos
Laminaria/microbiologia , Polissacarídeo-Liases/química , Polissacarídeo-Liases/isolamento & purificação , Vibrio/enzimologia , Ativação Enzimática , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Polissacarídeo-Liases/metabolismo , Especificidade por Substrato , Temperatura
19.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-254606

RESUMO

<p><b>AIM</b>The role of activated nuclear factor-kappa B(NF-kappaB) on the expression of heme oxygenase-1 induced by lipopolysaccharide (LPS) in rats' myocardium was obversed, and the effect exerted in endotoxic shock was explored.</p><p><b>METHODS</b>The changes in mean arterial pressure within 12 hours were recorded on a polygraph. The protein expression of NF-kappaB p65 in rats'myocardium, which were induced by lipopolysaccharide were measured with immunochemistry. The changes both of protein and gene expression of heme oxygenase-1 in rats' myocardium, which were induced by injection of LPS or preadministration of the specific inhibitor of NF-kappaB, pyrrolidine dithiocarbamate(PDTC), were examined by immunochemistry of reverse transcripted polymerase chain reaction.</p><p><b>RESULTS</b>(1) LPS caused a rapid decrease of MAP within 12 h( P < 0.01). (2) After LPS was administration, the protein expression of NF-kappaB p65 in both of micrangium endothelium within myocardium markedly increased at 0.5 h and 2 h, while decreased gradually at 6 h and 12 h. (3) ES group expressed as migration of acute inflammatory cells and dilation and stagnation in blood capillary, while the increase of HO-1 mRNA induced by LPS didn't change at the first 0.5 h, began at 2 h, peaked at 6 h, and declined at 12 h, respectively. The protein expression of HO-1 in micrangium endothelium within myocardium markedly increased and emerged in myocardium, and kept a high level at 6 h and 12 h. (4) When a specific inhibitor of NF-kappaB, PDTC, was applied to inhibit the level of NF-kappaB, we found that the pathomorphological changes of myocardium in ES rats were improved and both HO-1 mRNA and protein expression in myocardium markedly failed at 6 h.</p><p><b>CONCLUSION</b>NF-kappaB was activated on the stimulation of LPS, which brought about its translocation to the nucleus to act on transcription activity of HO-1 gene. NF-kappaB might be involved in its signal transductive mechanisms, which might be one of the important mechanism of LPS inducing the refractory low arterial pressure in ES rats.</p>


Assuntos
Animais , Masculino , Ratos , Heme Oxigenase-1 , Genética , Metabolismo , Lipopolissacarídeos , Miocárdio , Metabolismo , NF-kappa B , Metabolismo , Ratos Sprague-Dawley , Choque Séptico , Metabolismo
20.
Chinese Journal of Cardiology ; (12): 1037-1042, 2005.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-253014

RESUMO

<p><b>OBJECTIVE</b>To explore the mechanism and effect of sodium/hydrogen exchanger (Na(+)-H(+) exchanger, NHE), amiloride, on vessel stenosis.</p><p><b>METHODS</b>Thirty-two adult male New Zealand white rabbits were randomly divided into groups of amiloride intervention (IG, n = 12), balloon injury (BG, n = 10) and sham-operation (SG, n = 10). A 2.5 mm x 20 mm Foley's tube was used to injury left side iliac artery in the IG and BG groups, whereas a same Foley's tube was inserted into the vessel without any injuries in the SG group. Amiloride (5 mg.kg(-1).d(-1)) was intraperitoneally injected 3 days before balloon injuries and the same dosage normal saline was used in the same way in the BG group for 28 days after operation. The rabbits were killed and the iliac arteries were stained with Hematoxylin-Eosin, alpha-actin and Masson's trichrome to observe the morphologic changes in the vessel cava, neointima, media layer, and vascular smooth muscle cells (VSMCs) migration into the neointima and extracellular matrixes (ECMs).</p><p><b>RESULTS</b>Four weeks after balloon injuries in rabbits, a cave narrow of the iliac artery and neointima were found and the media layer (VSM layer) was proliferated. The quantities of NHE-1 protein from artery smooth muscle in all the groups were 0.21 +/- 0.02, 0.25 +/- 0.04 and 0.11 +/- 0.03 (P < 0.01), respectively. The difference between the BG and SG groups was significant, which indicated that the NHE-1 proteins increased after balloon injury. The quantities of NHE-1 protein from the IG group were lower than those from the BG group. The cave areas were 0.91 mm(2) +/- 0.23 mm(2), 0.68 mm(2) +/- 0.19 mm(2) and 1.08 mm(2) +/- 0.17 mm(2) (P < 0.01), respectively. The intima areas were 0.27 mm(2) +/- 0.15 mm(2), 0.67 mm(2) +/- 0.24 mm(2) and 0.05 mm(2) +/- 0.03 mm(2), respectively (P < 0.01). The ratios of intima to media area were 1.21 +/- 0.24, 1.39 +/- 0.26 and 0.15 +/- 0.08 (P < 0.01), respectively. Amiloride increased vessel cave areas, but decreased intima areas and intima to media ratios in the IG group. In the IG group, alpha-actin positive areas in neointima was higher (16,328.31 microm(2) +/- 6220.27 microm(2)) than those in the SG group (4164.15 microm(2) +/- 1788.37 microm(2)) (P < 0.01). ECMs areas in neointima in the IG group were lower (8910.62 microm(2) +/- 7041.62 microm(2)) than those in the SG group (33,358.76 microm(2) +/- 7290.17 microm(2)) (P < 0.01).</p><p><b>CONCLUSIONS</b>Balloon injuries of iliac artery in rabbits induce VSMCs proliferation, migration, narrowed cave and vessel stenosis. Amiloride, a NHE-1 inhibitor, may relieve this vessel stenosis.</p>


Assuntos
Animais , Masculino , Coelhos , Amilorida , Usos Terapêuticos , Angioplastia com Balão , Vasos Sanguíneos , Ferimentos e Lesões , Patologia , Constrição Patológica , Reestenose Coronária , Tratamento Farmacológico , Metabolismo , Patologia , Artéria Ilíaca , Ferimentos e Lesões , Patologia , Músculo Liso Vascular , Metabolismo , Trocadores de Sódio-Hidrogênio , Metabolismo , Stents
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