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1.
Int J Biol Macromol ; 241: 124638, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37119889

RESUMEN

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.


Asunto(s)
Compuestos de Amonio , Hipersensibilidad , Humanos , Alginatos/farmacología , Polisacáridos/farmacología , Hipersensibilidad/tratamiento farmacológico , Mastocitos
2.
Genes Dis ; 9(1): 51-61, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35005107

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-32758223

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Animales , Línea Celular Tumoral , Humanos , Ratones , Células RAW 264.7
4.
Carbohydr Polym ; 194: 365-374, 2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-29801851

RESUMEN

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.


Asunto(s)
Alginatos/efectos adversos , Anticoagulantes/efectos adversos , Hemorragia/tratamiento farmacológico , Polisacáridos/efectos adversos , Sulfatos/efectos adversos , Alginatos/química , Alginatos/farmacología , Animales , Anticoagulantes/química , Anticoagulantes/farmacología , Pruebas de Coagulación Sanguínea , Conformación de Carbohidratos , Femenino , Masculino , Ratones , Ratones Endogámicos , Agregación Plaquetaria/efectos de los fármacos , Polisacáridos/química , Polisacáridos/farmacología , Ratas , Ratas Wistar , Sulfatos/química , Sulfatos/farmacología
5.
Carbohydr Polym ; 144: 330-7, 2016 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-27083824

RESUMEN

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.


Asunto(s)
Alginatos/química , Anticoagulantes/química , Polisacáridos/química , Alginatos/farmacología , Animales , Anticoagulantes/farmacología , Línea Celular Tumoral , Estabilidad de Medicamentos , Humanos , Hipersensibilidad/etiología , Ratones , Peso Molecular , Polisacáridos/farmacología , Control de Calidad , Azufre/química
6.
Food Funct ; 6(9): 3056-64, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26205038

RESUMEN

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.


Asunto(s)
Caquexia/metabolismo , Fucus/química , Ácidos Hexurónicos/farmacología , Mitocondrias/efectos de los fármacos , Células Musculares/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Caquexia/tratamiento farmacológico , Caquexia/enzimología , Línea Celular , Glutatión/metabolismo , Ácidos Hexurónicos/química , Humanos , Ratones , Mitocondrias/metabolismo , Peso Molecular , Células Musculares/enzimología , Células Musculares/metabolismo , Músculo Esquelético/enzimología , Músculo Esquelético/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Algas Marinas/química , Superóxido Dismutasa/metabolismo
7.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-250334

RESUMEN

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.


Asunto(s)
Animales , Ratones , Proliferación Celular , Pulmón , Patología , Células Madre Mesenquimatosas , Biología Celular , Ratones Endogámicos C57BL , Enfermedad Pulmonar Obstructiva Crónica , Patología , Terapéutica
8.
Yao Xue Xue Bao ; 49(7): 1049-53, 2014 Jul.
Artículo en Chino | MEDLINE | ID: mdl-25233639

RESUMEN

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.


Asunto(s)
Anticoagulantes/química , Enoxaparina/química , Inhibidores del Factor Xa/química , Trombina/antagonistas & inhibidores
9.
Eur J Med Chem ; 85: 304-10, 2014 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-25089813

RESUMEN

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).


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Ácidos Hexurónicos/química , Ácidos Hexurónicos/farmacología , Hipolipemiantes/química , Hipolipemiantes/farmacología , Sulfatos/química , Acetil-CoA Carboxilasa/metabolismo , Proliferación Celular/efectos de los fármacos , Colesterol/metabolismo , Colesterol 7-alfa-Hidroxilasa/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Ácidos Grasos/metabolismo , Células Hep G2 , Humanos , Hidroximetilglutaril-CoA Reductasas/metabolismo , Peso Molecular , Oxidación-Reducción/efectos de los fármacos , Fosforilación/efectos de los fármacos , Receptores de LDL/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Triglicéridos/metabolismo
10.
Mar Drugs ; 11(4): 1113-25, 2013 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-23549283

RESUMEN

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.


Asunto(s)
Alginatos/farmacocinética , Cromatografía Líquida de Alta Presión/métodos , Ácido Láctico/química , Nanopartículas , Ácido Poliglicólico/química , Administración Oral , Alginatos/análisis , Alginatos/química , Animales , Disponibilidad Biológica , Calibración , Femenino , Fluorescencia , Inyecciones Intravenosas , Límite de Detección , Masculino , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ratas , Ratas Wistar , Sulfatos/química
11.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-243205

RESUMEN

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.


Asunto(s)
Animales , Humanos , Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina , Genética , Sitios Genéticos , ARN sin Sentido , Fisiología , ARN Largo no Codificante , Fisiología
12.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-266098

RESUMEN

<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>


Asunto(s)
Humanos , Bacterias , Mano , Microbiología , Pruebas de Sensibilidad Microbiana , Prácticas Mortuorias , Exposición Profesional
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(9): 2484-7, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-21105423

RESUMEN

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%.


Asunto(s)
Glicosaminoglicanos/química , Riñón/química , Animales , Cromatografía Líquida de Alta Presión , Cromatografía por Intercambio Iónico , Dermatán Sulfato/química , Disacáridos/química , Electroforesis , Ratas , Ratas Wistar
14.
Asian Journal of Andrology ; (6): 266-271, 2009.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-284688

RESUMEN

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.


Asunto(s)
Humanos , Recién Nacido , Andrógenos , Farmacología , Células Cultivadas , Regulación hacia Abajo , Combinación de Medicamentos , Endotelio Vascular , Metabolismo , Lipoproteínas , Genética , Metabolismo , Subunidad p50 de NF-kappa B , Genética , ARN Mensajero , Metabolismo , Testosterona , Farmacología , Factor de Necrosis Tumoral alfa , Farmacología
15.
Chinese Medical Journal ; (24): 241-247, 2008.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-255728

RESUMEN

<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>


Asunto(s)
Animales , Masculino , Ratas , Aorta , Fisiología , Monóxido de Carbono , Sangre , Endotelio Vascular , Fisiología , Inducción Enzimática , Hemo-Oxigenasa 1 , Genética , Hemina , Farmacología , Resistencia a la Insulina , Óxido Nítrico , Sangre , Estrés Oxidativo , Ratas Sprague-Dawley , Sístole
16.
National Journal of Andrology ; (12): 777-779, 2007.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-232066

RESUMEN

<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>


Asunto(s)
Humanos , Antagonistas de Receptores Androgénicos , Western Blotting , Células Cultivadas , Células Endoteliales , Biología Celular , Metabolismo , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular , Metabolismo , Proteína Quinasa 1 Activada por Mitógenos , Metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Metabolismo , Fosforilación , Receptores Androgénicos , Metabolismo , Testosterona , Farmacología , Venas Umbilicales , Biología Celular
17.
Acta Biochim Biophys Sin (Shanghai) ; 38(9): 633-8, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16953302

RESUMEN

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.


Asunto(s)
Laminaria/microbiología , Polisacárido Liasas/química , Polisacárido Liasas/aislamiento & purificación , Vibrio/enzimología , Activación Enzimática , Estabilidad de Enzimas , Concentración de Iones de Hidrógeno , Polisacárido Liasas/metabolismo , Especificidad por Sustrato , Temperatura
19.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-254606

RESUMEN

<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>


Asunto(s)
Animales , Masculino , Ratas , Hemo-Oxigenasa 1 , Genética , Metabolismo , Lipopolisacáridos , Miocardio , Metabolismo , FN-kappa B , Metabolismo , Ratas Sprague-Dawley , Choque Séptico , Metabolismo
20.
National Journal of Andrology ; (12): 584-586, 2005.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-339475

RESUMEN

<p><b>OBJECTIVE</b>To investigate the effect of testosterone with varied concentrations on the tPA and PAI-1 mRNA levels of Human umbilical vein endothelial cells (HUVEC).</p><p><b>METHODS</b>HUVEC within 2 - 3 passages were cultured with testosterone (3, 30, 3 x 10(3), 3 x 10(4) nmol/L) , and the control confluent cells were cultured in the same medium without steroid for 48 hours. RT-PCR was carried out to detect tPA and PAI-1 mRNA levels.</p><p><b>RESULTS</b>tPA mRNA level increased, while PAI-1 mRNA levels decreased significantly, at the testosterone concentrations ranging from 3 to 3 x 10(3) nmol/L (P < 0.05). Both tPA and PAI-1 mRNA level decreased obviously of 3 x 10(4) nmol/L group.</p><p><b>CONCLUSION</b>The results indicated that testosterone could stimulate tPA gene expression, while decreased PAI-1 mRNA level of HUVEC, which suggested that testosterone might have beneficial effects on preventing male's thrombotic diseases.</p>


Asunto(s)
Humanos , Masculino , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Endoteliales , Metabolismo , Endotelio Vascular , Biología Celular , Metabolismo , Inhibidor 1 de Activador Plasminogénico , Genética , ARN Mensajero , Genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Testosterona , Farmacología , Activador de Tejido Plasminógeno , Genética , Venas Umbilicales , Biología Celular
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