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1Strategies to modulate the intestinal microbiota and their effects on nutrient utilization, performance, and health of poultry显示文摘Poultry is widely produced and consumed meat globally.Its demand is expected to continue increasing to meet the animal protein requirement for ever-increasing human population.Thus,the challenge that poultry scientists and industry face are to produce sufficient amount of poultry meat in the most efficient way.In the past,using antibiotics to promote the growth of poultry and manage gut microbiota was a norm.However,due to concerns over potential fatalistic impacts on food animals and indirectly to humans,their use as feed additives are banned or regulated in several jurisdictions.In this changed context,several alternative strategies have been proposed with some success that mimics the functions of antibiotics as growth promoters and modulate gut microbiota for their beneficial roles.These include the use of probiotics,prebiotics,organic acids,and exogenous enzyme,among others.Gut microbiota and their metabolic products improve nutrient digestion,absorption,metabolism,and overall health and growth performance of poultry.This paper reviews the available information on the effect of feed additives used to modulate intestinal microbiota of poultry and their effects on overall health and growth performance.Understanding these functions and interactions will help to develop new dietary and managerial strategies that will ultimately lead to enhanced feed utilization and improved growth performance of poultry.This review will help future researchers and industry to identify alternative feed ingredients having properties like prebiotics,probiotics,organic acids,and exogenous enzymes.Sudhir Yadav Rajesh Jha 2019Journal of Animal Science and Biotechnology2019,10,3:37
2A meta-analysis of oxidative stress markers in schizophrenia显示文摘Oxidative stress has been identified as a possible element in the neuropathological processes of schizophrenia(SCZ).Alteration of oxidative stress markers has been reported in SCZ studies,but with inconsistent results.To evaluate the risk of oxidative stress to schizophrenia,a meta-analysis was conducted,including five markers of oxidative stress [thiobarbituric reactive substances(TBARS),nitric oxide(NO),catalase(CAT),glutathione peroxidase(GP) and superoxide dismutase(SOD)] in SCZ patients versus healthy controls.This study showed that TBARS and NO significantly increased in SCZ,while SOD activity significantly decreased in the disorganized type of SCZ patients.No significant effect size was found for the activities of GP and CAT in SCZ patients(P>0.05).Egger’s regression test observed no significant publication bias across the oxidative stress markers,but found high heterogeneities in all the 5 markers.The subgroup analysis suggested that the ethnicity,sample size of patients and sample sources may contribute to the heterogeneity of the results for TBARS,NO and SOD.The result further demonstrated the involvement of oxidative stress in the pathophysiology of schizophrenia.ZHANG Ming1,2,ZHAO ZhongMing3,HE Lin1,2,4 & WAN ChunLing1,2 1 Bio-X Center,Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders(Ministry of Education),Shanghai Jiao Tong University,Shanghai 200030,China 2 Institutes for Nutritional Sciences,Shanghai Institute of Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China 3 Departments of Biomedical Informatics,Psychiatry,and Cancer Biology,Vanderbilt University Medical Center,Nashville,TN 37232,USA 4 Institutes of Biomedical Sciences,Fudan University,Shanghai 200032,China 2010Science China(Life Sciences)2010,53,1:32
3A hepatoprotection study of Radix Bupleuri on acetaminophen-induced liver injury based on CYP450 inhibition显示文摘We investigated the potential hepatoprotective effect of Radix Bupleuri(RB) by inducing acute liver injury(ALI) in an animal model using acetaminophen(APAP) after pretreatment with RB aqueous extract for three consecutive days. Compared to those of the APAP group, the biochemical and histological results of the RB pretreatment group showed lower serum aspartate transaminase(AST) and alanine transaminase(ALT) levels as well as less liver damage. Pharmacokinetic study of the toxicity related marker acetaminophen-cysteine(APC) revealed a lower exposure level in rats, suggesting that RB alleviated APAP-induced liver damage by preventing glutathione(GSH) depletion. The results of cocktail approach showed significant inhibition of CYP2 E1 and CYP3 A activity. Further investigation revealed the increasing of CYP2 E1 and CYP3 A protein was significantly inhibited in pretreatment group,while no obvious effect on gene expression was found. Therefore, this study clearly demonstrates that RB exhibited significant protective action against APAP-induced acute live injury via pretreatment, and which is partly through inhibiting the increase of activity and translation of cytochrome P450 enzymes, rather than gene transcription.WANG Yu-Xin DU Yi LIU Xia-Fei YANG Fang-Xiu WU Xiao TAN Li LU Yi-Hong ZHANG Jing-Wei ZHOU Fang WANG Guang-Ji 2019Chinese Journal of Natural Medicines2019,17,7:18
4Advances in understanding and treating liver diseases during pregnancy:A review显示文摘Liver disease in pregnancy is rare but pregnancyrelated liver diseases may cause threat to fetal and maternal survival.It includes pre-eclampsia;eclampsia;haemolysis,elevated liver enzymes,and low platelets syndrome;acute fatty liver of pregnancy;hyperemesis gravidarum;and intrahepatic cholestasis of pregnancy.Recent basic researches have shown the various etiologies involved in this disease entity.With these advances,rapid diagnosis is essential for severe cases since the decision of immediate delivery is important for maternal and fetal survival.The other therapeutic options have also been shown in recent reports based on the clinical trials and cooperation and information sharing between hepatologist and gynecologist is important for timely therapeutic intervention.Therefore,correct understandings of diseases and differential diagnosis from the pre-existing and co-incidental liver diseases during the pregnancy will help to achieve better prognosis.Therefore,here we review and summarized recent advances in understanding the etiologies,clinical courses and management of liver disease in pregnancy.This information will contribute to physicians for diagnosis of disease and optimum management of patients.Kenya Kamimura Hiroyuki Abe Hirokazu Kawai Hiroteru Kamimura Yuji Kobayashi Minoru Nomoto Yutaka Aoyagi Shuji Terai 2015World Journal of Gastroenterology2015,21,17:15
5丹参多酚酸盐治疗老年糖尿病肾病的临床研究显示文摘目的通过研究丹参多酚酸盐对老年糖尿病肾病的疗效及对尿N-乙酰β-D-葡萄糖苷酶(NAG)、转化生长因子-β1(TGF-β1)、单核细胞趋化蛋白-1(MCP-1)的影响,探讨丹参多酚酸盐治疗糖尿病肾病的机制及糖尿病肾病发病过程中的关键因子。方法 90例糖尿病肾病患者随机分为2组,每组45例,对照组给予常规治疗,治疗组在对照组的基础上增加丹参多酚酸盐治疗,将200 mg注射用丹参多酚酸盐加入200 m L生理盐水中,静脉滴注,1次/d,4周为1个疗程。比较两组患者的疗效及NAG、尿微量白蛋白(m ALB)、β2-微球蛋白(β2-MG)、TGF-β1、MCP-1和生化指标的变化。结果治疗后对照组和治疗组的有效率分别为82.22%、91.11%,两组比较差异具有统计学意义(P<0.05)。治疗后,两组的尿白蛋白排泄率(UAER)、肌酐(Cr)、血尿素氮(BUN)均较治疗前明显好转,且差异具有统计学意义(P<0.01);与对照组治疗后比较,治疗组的UAER、纤维蛋白原(FIB)明显改善,且差异具有统计学意义(P<0.01)。治疗后,两组的NAG、m ALB、β2-MG、TGF-β1和MCP-1均明显好转,与治疗前相比差异具有统计学意义(P<0.01);与对照组治疗后比较,治疗组的NAG、β2-MG、TGF-β1和MCP-1显著改善,且差异具有统计学意义(P<0.01),两组的m ALB差异不具有统计学意义。结论丹参多酚酸盐对糖尿病肾病的治疗作用主要通过调节TGF-β1和MCP-1水平、延缓近端肾小管损伤实现。赵琪 冯春玲 孙玉珍 刘健 张雪 李晓萌 2015现代药物与临床2015,30,4:15
6二氯喹啉酸胁迫下降解菌对烤烟叶片中活性氧及保护酶的影响显示文摘研究了二氯喹啉酸胁迫条件下,向土壤施入降解菌对烤烟叶片中活性氧及保护酶的影响。结果表明,移栽后20 d时,与对照相比,施入降解菌能降低烟叶中超氧阴离子自由基(O2.-)、羟自由基(.OH)、过氧化氢(H2O2)和丙二醛(MDA)含量,分别降低了23%、39%、25%、49%;能提高烟叶中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)及过氧化物酶(POD)活性,分别提高了66%、51%、48%。总体上,随着降解菌施入量的增加,烟叶中防御酶活性提高,MDA和活性氧含量降低,在每克干土中施入降解菌量为3×1010个时缓解二氯喹啉酸胁迫效果最好。左涛 刘华山 韩锦峰 徐淑霞 王晓军 袁仕豪 蒲文宣 汪耀富 易建华 Hua-shan Jin-feng Shu-xia Xiao-jun Shi-hao Wen-xuan Yao-fu Jian-hua 2010河南农业科学2010,39,12:13
7Microbial Degradation of Organophosphate Pesticides: A Review显示文摘Pesticides have become an inevitable part of the modern environment as they are widely used in agriculture,household,and public health sectors and,hence,are extensively distributed throughout most ecosystems.Currently,organophosphate pesticides are the most commercially favored group of pesticides,with large application areas all over the world.Depending on their fate,these organophosphorus compounds may become bioavailable for microbial degradation.Environmental microbes,such as Aspergillus,Pseudomonas,Chlorella,and Arthrobacter,are capable of coupling a variety of physical and biochemical mechanisms for the degradation of organophosphate pesticides,including adsorption,hydrolysis of P–O alkyl and aryl bonds,photodegradation,and enzymatic mineralization.Enzymes,such as esterase,diisopropyl fluorophosphatase,phosphotriesterase,somanase,parathion hydrolase,and paraoxonase,have been isolated from microbes to study and understand the catabolic pathways involved in the biotransformation of these xenobiotic compounds.This review highlights various aspects of biodegradation of organophosphate pesticides along with biological and molecular characterization of some organophosphate pesticide-degrading bacteria.Shardendu KUMAR Garima KAUSHIK Mohd Ashraf DAR Surendra NIMESH Ulrico Javier LOPEZ-CHUKEN Juan Francisco VILLARREAL-CHIU 2018Pedosphere2018,28,2:12
8Peripheral clearance of brain-derived Aβ in Alzheimer's disease: pathophysiology and therapeutic perspectives显示文摘Alzheimer’s disease(AD)is the most common type of dementia,and no disease-modifying treatments are available to halt or slow its progression.Amyloid-beta(Aβ)is suggested to play a pivotal role in the pathogenesis of AD,and clearance of Aβfrom the brain becomes a main therapeutic strategy for AD.Recent studies found that Aβclearance in the periphery contributes substantially to reducing Aβaccumulation in the brain.Therefore,understanding the mechanism of how Aβis cleared in the periphery is important for the development of effective therapies for AD.In this review,we summarized recent findings on the mechanisms of Aβefflux from the brain to the periphery and discuss where and how the brain-derived Aβis cleared in the periphery.Based on these findings,we propose future strategies to enhance peripheral Aβclearance for the prevention and treatment of AD.This review provides a novel perspective to understand the pathogenesis of AD and develop interventions for this disease from a systemic approach.Yuan Cheng Ding-Yuan Tian Yan-Jiang Wang 2020Translational Neurodegeneration2020,9,2:12
9Hypolipidaemic and antioxidant effect of Enicostemma littorale Blume显示文摘Objective:To investigate the hypolipidaemic and antioxidant effects of aqueous leaf extract of Enicoslemma littorale(E.littorale)Blume(Ens)against ethanol induced hepatic injury in albino rats.Methods:Male albino rats of six numbers in each group were undertaken for study.Hypolipidaemic and antioxidant effect of E.littorale Blume(Ens)aqueous leaf extract at a dosage of 250 mg/kg bw was evaluated.Results:Levels of serum and tissue cholesterol,triglycerides and free fatty acids were elevated and levels of tissue thiobarbituric acid reactive substances(TBARS)and lipid hydroperoxide were increased in ethanol treated rats.The activity levels of liver antioxidant enzymes such as superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GPX)and glutathione-s-transferase(GST)were decreased.After adiminstration of extract of E,littorale Blume,levels of cholesterol,triglycerides and free fatty acids were decreased in serum and liver tissue,levels of TBARS and lipid hydroperoxide were decreased,and Ever antioxidant enzymes were increased in liver tissue;Conclusions:It can be concluded that the aqueous leaf extract of E,littorale Blume(Ens)has potent restorative effect on hyperlipidaemic and oxidative stress.Thirumalai T Viviyan Therasa S Elumalai EK David E 2011Asian Pacific Journal of Tropical Biomedicine2011,1,5:12
10Study on the physiological indices of Pinus sibirica and Pinus koraiensis seedlings under cold stress显示文摘Although Pinus sibirica and Pinus koraiensis are resistant to cold or low temperatures in the cold temperate regions of the northern hemisphere,the former has a stronger cold resistance.Research has been limited to the comparison of physiological responses of the two species to cold stress.In this study,5-year-old seedlings of P.sibirica and P.koraiensis were subjected to six temperature treatments,[20℃(control),0℃,-20℃,-40℃,-60℃,and-80℃],under different stress periods(6,12,24,and 48 h).The results showed that differences in each physiological index were significant between P.sibirica and P.koraiensis,except for the permeability of cell membranes,reactive oxygen species,proline and soluble proteins.An ANOVA test indicated that there were extreme differences among the temperatures for each index,stress time and temperature 9 time for most indices.All indices showed a similar trend for P.sibirica and P.koraiensis with decreasing temperature or the extension of stress time.Soluble sugars and proline increased at 0 to-20℃and then remained unchanged with temperature decline.Other indices showed an increase from 20 to-20℃,stable from-20 to-40℃and a decrease from-40 to-80℃.All the indices increased and then declined along with the prolonged cold stress time,except for the control.From 0 to-40℃,the permeability of cell membranes,relative conductivity,reactive oxygen species and malonaldehyde of P.koraiensis seedlings were higher than in P.sibirica,but superoxide dismutase,peroxidase,catalase activity and soluble sugars,proline,and soluble proteins content emerged as opposite.This study compared the physiological mechanism responses to cold stress between P.sibirica and P.koraiensis to provide the basis for the introduction,distribution,and genetic improvement of these coniferous species.Fang Wang Deyang Liang Xiaona Pei Qinhui Zhang Peng Zhang Jianqiu Zhang Zhimin Lu Yuchun Yang Guifeng Liu Xiyang Zhao 2019Journal of Forestry Research2019,30,4:12
11A Regulatory Module Controlling CA-Mediated Endosperm Cell Expansion Is Critical for Seed Germination in Arabidopsis显示文摘A key component of seed germination is the interplay of mechanical forces governing embryo growth and the surrounding restraining endosperm tissue.Endosperm cell separation is therefore thought to play a critical role in the control of this developmental transition.Here we demonstrate that in Arabidopsis thaliana seeds,endosperm cell expansion is a key component of germination.Endosperm cells expand to accommodate embryo growth prior to germination.We show that this is an actively regulated process supported by spatiotemporal control of the cell expansion gene EXPANSIN 2 (EXPA2).The NAC transcription factors NAC25 and NACIL were identified as upstream regulators of EXPA2 expression,gibbereliinmediated endosperm expansion,and seed germination.The DELLA protein RGL2 repressed activation of the EXPA2 promoter by NAC25/NACIL.Taken together,our findings uncover a key role of the GA/ DELLA-NAC25/NACIL-EXPA2 network in regulating endosperm cell expansion to control the seed-toseedling transition.Rocio Sanchez-Montesino Laura Bouza-Morcillo Julietta Marquez Melania Ghita Salva Duran-Nebreda Luis Gomez Michael J.Holdsworth George Bassel Luis Onate-Sanchez 2019Molecular Plant2019,12,1:11
12Diet supplementation with an organic acids-based formulation affects gut microbiota and expression of gut barrier genes in broilers显示文摘This study was designed to study the effect of diet supplementation with an organic acids-based formulation(OABF) on luminal-and mucosa-associated bacteria, concentration of volatile fatty acids(VFA), microbial glycolytic enzyme activity and expression of mucin 2(MUC2), immunoglobulin A(IgA)and tight junction protein, i.e., zonula occludens-1(ZO1), zonula occludens-2(ZO2), claudin-1(CLDN1),claudin-5(CLDN5) and occludin(OCLN), genes at the ileal and cecal level. A 2 × 2 factorial design was used having OABF inclusion and avilamycin as main factors. Subsequently, 544 day-old male Cobb broilers were allocated in the following 4 treatments, each with 8 replicates: no additions(CON), 1 g OABF/kg diet(OA),2.5 mg avilamycin/kg diet(AV) and combination of OA and AV(OAAV). The trial lasted for 42 days. In the ileum, OAAV resulted in lower mucosa-associated total bacteria levels(PO × A= 0.028) compared with AV.In addition, ileal digesta levels of Clostridium perfringens subgroup were decreased by avilamycin(PA= 0.045). Inclusion of OABF stimulated the activity of microbial glycolytic enzymes, whereas avilamycin resulted in lower acetate(PA= 0.021) and higher butyrate(PA= 0.010) molar ratios. Expression of ZO1 and CLDN5 was down-regulated by both OABF(PO= 0.016 and PO= 0.003, respectively) and avilamycin(PA= 0.016 and PA= 0.001, respectively). In addition, CLDN1 was down-regulated in AV compared with CON(PO × A= 0.012). Furthermore, OABF down-regulated MUC2(PO= 0.027), whereas avilamycin down-regulated nuclear factor kappa B subunit 1(NFKB1)(PA= 0.024), toll-like receptor 2 family member B(TLR2B)(PA= 0.011) and toll-like receptor 4(TLR4)(PA= 0.014) expression. In the ceca, OABF inclusion increased digesta levels of Clostridium coccoides(PO= 0.018) and Clostridium leptum(PO= 0.040) subgroups, while it up-regulated MUC2 expression(PO= 0.014). Avilamycin(PA= 0.044) and interaction(PO × A< 0.001) effects for IgA expression were noted, with CON having higher IgA expression compared with AV. In conclusion, new findings regarding OABF inclusion effects on an array of relevant biomarkers for broiler gut ecology have been reported and discussed in parallel with avilamycin effects used as a positive control. This new knowledge is expected to provide a response baseline for follow up trials under various stress and challenge conditions.Irida Palamidi Konstantinos C.Mountzouris 2018Animal Nutrition2018,,4:11
13Deubiquitinating enzyme regulation of the p53 pathway: A lesson from Otub1显示文摘Deubiquitination has emerged as an important mechanism of p53 regulation. A number of deubiquitinating enzymes(DUBs) from the ubiquitin-specific protease family have been shown to regulate the p53-MDM2-MDMX networks. We recently reported that Otub1, a DUB from the OTU-domain containing protease family, is a novel p53 regulator. Interestingly, Otub1 abrogates p53 ubiquitination and stabilizes and activates p53 in cells independently of its deubiquitinating enzyme activity. Instead, it does so by inhibiting the MDM2 cognate ubiquitin-conjugating enzyme(E2) UbcH5. Otub1 also regulates other biological signaling through this non-canonical mechanism, suppression of E2, including the inhibition of DNA-damage-induced chromatin ubiquitination. Thus, Otub1 evolves as a unique DUB that mainly suppresses E2 to regulate substrates. Here we review the current progress made towards the understanding of the complex regulation of the p53 tumor suppressor pathway by DUBs, the biological function of Otub1 including its positive regulation of p53, and the mechanistic insights into how Otub1 suppresses E2.Xiao-Xin Sun Mu-Shui Dai 2014World Journal of Biological Chemistry2014,5,2:10
14Antihyperglycemic effect of Hypericum perforatum ethyl acetate extract on streptozotocin-induced diabetic rats显示文摘Objective:To evaluate the antihyperglycemic activity of ethyl acetate extract of Hypericum perforatum(H.perforatum)in streptozotocin(STZ)-induced diabetic rats.Methods:Acute toxicity and oral glucose tolerance lest were performed in normal rats.Male albino rats were rendered diabetic by ST/(40 mg/kg,intraperitoneally).H.perforatum ethyl acetate extract was orally administered to diabetic rats at SO,100 and 200 mg/kg doses for 15 days to determine the antihyperglycemic activity.Biochemical parameters were determined at the end of the treatment.Results:H.perforatum ethyl acetate extract showed dose dependant fall in fasting blood glucose(FBG).After 30 min of extract administration,FBG was reduced significantly when compared with normal rats.H.perforatum ethyl acetate extract produced significant reduction in plasma glucose level,serum total cholesterol,triglycerides,glucose-6-phosphatase levels.Tissue glycogen content,HDL-cholesterol,glucose-6-phosphate dehydrogenase were significantly increased compared with diabetic control.No death or lethal effect was observed in the toxic study.Conclusions:The results demonstrate that H.perforatum ethyl acetate extract possesses potent antihyperglycemic activity in STZ induced diabetic rats.Arokiyaraj S Balamurugan R Augustian P 2011Asian Pacific Journal of Tropical Biomedicine2011,1,5:9
15Concepts of oxidative stress and antioxidant defense in Crohn's disease显示文摘Oxygen free radical and lipid peroxides(oxidative stress)are highly reactive and represent very damaging compounds.Oxidative stress could be a major contributing factor to the tissue injury and fibrosis that characterize Crohn’s disease.An imbalance between increased reactive oxygen species levels and decreased antioxidant defenses occurs in Crohn’s patients.Decreased blood levels of vitamins C and E and decreased intestinal mucosal levels of CuZn superoxide dismutase,glutathione,vitamin A,C,E,andβ-carotene have been reported for Crohn’s patients.Increased levels of proinflammatory cytokines,such as interleukin-1 and-8 and tumor necrosis factor,have been detected in inflammatory bowel disease.Oxidative stress significantly increased the production of neutrophils,chemokines,and interleukin-8.These effects were inhibited by antioxidant vitamins and arachidonic acid metabolite inhibitors in human intestinal smooth muscle cells isolated from the bowels of Crohn’s disease patients.The main pathological feature of Crohn’s disease is an infiltration of polymorphonuclear neutrophils and mononuclear cells into the affected part of the intestine.Activated neutrophils produce noxious substances that cause inflammation and tissue injury.Due to the physiological and biochemical actions of reactive oxygen species and lipid peroxides,many of the clinical and pathophysiological features of Crohn’s disease might be explained by an imbalance of increased reactive oxygen species and a net decrease of antioxidant molecules.This review describes the general concepts of free radical,lipid peroxide and antioxidant activities and eventually illustrates their interferences in the development of Crohn’s strictures.Mohammed A Alzoghaibi 2013World Journal of Gastroenterology2013,19,39:9
16Excessive Cu and Zn affecting on distribution of the metals and activities of glycolytic and nitrogen incorporating key enzymes in mycelia of ectomycorrhizal fungi Suillus bovinus显示文摘Concentration of copper and zinc in isolated Suillus bovinus mycelia, used nutrient solution and 0.5 mol/L EDTA mycelia washing solution were measured to investigate the distribution of heavy metals in mycelia growth in excess copper or zinc nutrient solution. Treated with zinc, most of added zinc maintained in used solution, and 9.8%/14.6% was in/on mycelia in treatment, and in treatment 2 was 3.9%/8.0% in/on mycelia. In the copper applications, copper stimulated in more than on mycelia, i.e., 25.9%/4.5% in/on mycelia in treatment, and 7%/18.8% in/on mycelia while most of copper retained in used nutrient solution. Certain amount of copper or zinc uptake by mycelia led to pronounced influence on glycolysis and nitrogen incorporating process of Suillus bovinus, while the tested enzymes kept constant in treatment. In crude extracts of copper treatment 2 mycelia, activities of HK, PFK and GS were inhibited and decrease to 63%, 48% and 38% and GlDH increased by 68% of the control, respectively. The behaviors of these tested enzymes toward zinc corresponded in general with that towards copper. The potential protection of Suillus bovinus for its host plant under excess copper or zinc threaten was discussed.HUANG Yi, TAO Shu(Department of Urban and Environmental Sciences, Peking University, Beijing 100871, China. 2001Journal of Environmental Sciences2001,13,3:9
17Salvianolic acid B modulates the expression of drug-metabolizing enzymes in HepG2 cells显示文摘BACKGROUND: Enzymes involved in drug and xenobiotic metabolism have been considered to exist in two groups: phase I and phase II enzymes. Cytochrome P450 isoenzymes (CYPs) are the most important phase I enzymes in the metabolism of xenobiotics. The products of phase I metabolism are then acted upon by phase II enzymes, including glutathione S-transferases (GSTs). Herbs that inhibit CYPs such as CYP3A4 or that induce GSTs may have the potential to protect against chemical carcinogenesis since the mutagenic effects of carcinogens are often mediated through an excess of CYP-generated reactive intermediates. This study was designed to investigate the effects of salvianolic acid B (Sal B), a pure compound extracted from Radix Salviae Miltiorrhizae, a Chinese herb, on cell proliferation and CYP1A2 and CYP3A4 mRNA expression in the presence or absence of rifampicin, a potent inducer of CYPs and GST protein expression in HepG2 cells. METHODS: HepG2 cells were incubated with different concentrations of Sal B. Cell proliferation was determined by SYTOX-Green nucleic acid staining. CYP3A4 and CYP1A2 mRNA expression was assayed by real-time PCR. GST protein expression was analyzed by Western blotting. RESULTS: Low concentrations of Sal B (0-20 μmol/L) had no significant effects on cell proliferation, while higher concentrations (100-250 μmol/L) significantly inhibited proliferation in a concentration-dependent manner. Ten μmol/L Sal B, but not 1 μmol/L, down-regulated CYP3A4 and CYP1A2 mRNA expression after 24 hours of incubation, whereas both 1 and 10 μmol/L Sal B down-regulated CYP3A4mRNA expression after 96 hours of incubation; moreover, 1 and 10 μmol/L Sal B inhibited CYP3A4 mRNA expression induced by rifampicin. Both 1 μmol/L and 10 μmol/L Sal B increased GST expression. CONCLUSION: Sal B inhibits CYP3A4 and CYP1A2 mRNA expression and induces GST expression in HepG2 cells.Hani El-Nezami 2011Hepatobiliary & Pancreatic Diseases International2011,10,5:9
18Nrf2 and Snail-1 in the prevention of experimental liver fibrosis by caffeine显示文摘AIM:To determine the molecular mechanisms involved in experimental hepatic fibrosis prevention by caffeine(CFA).METHODS:Liver fibrosis was induced in Wistar rats by intraperitoneal thioacetamide or bile duct ligation and they were concomitantly treated with CFA(15 mg/kg per day).Fibrosis and inflammatory cell infiltrate were evaluated and classified by Knodell index.Inflammatory infiltrate was quantified by immunohistochemistry(anti-CD11b).Gene expression was analyzed by quantitative reverse transcription-polymerase chain reaction for collagenⅠ?(Col-1),connective tissue growth factor(CTGF),transforming growth factorβ1(TGF-β1),tumor necrosis factor alpha(TNF-α),interleukin-1(IL-1),IL-6,superoxide dismutase(SOD)and catalase(CAT).Activation of Nrf2 and Snail-1 was analyzed by Westernblot.TNF-αexpression was proved by enzyme-linked immunosorbant assay,CAT activity was performed by zymography.RESULTS:CFA treatment diminished fibrosis index in treated animals.The Knodell index showed both lower fibrosis and necroinflammation.Expression of profibrogenic genes CTGF,Col-1 and TGF-β1 and proinflammatory genes TNF-α,IL-6 and IL-1 was substantially diminished with CFA treatment with less CD11b positive areas.Significantly lower values of transcriptional factor Snail-1 were detected in CFA treated rats compared with cirrhotic rats without treatment;in contrast Nrf2was increased in the presence of CFA.Expression of SOD and CAT was greater in animals treated with CFA showing a strong correlation between mRNA expression and enzyme activity.CONCLUSION:Our results suggest that CFA inhibits the transcriptional factor Snail-1,down-regulating profibrogenic genes,and activates Nrf2 inducing antioxidant enzymes system,preventing inflammation and fibrosis.Daniela Gordillo-Bastidas Edén Oceguera-Contreras Adriana Salazar-Montes Jaime González-Cuevas Luis Daniel Hernández-Ortega Juan Armendáriz-Borunda 2013World Journal of Gastroenterology2013,19,47:7
19Glycogenic hepatopathy:A narrative review显示文摘Glycogenic hepatopathy(GH) is a rare complication of the poorly controlled diabetes mellitus characterized by the transient liver dysfunction with elevated liver enzymes and associated hepatomegaly caused by the reversible accumulation of excess glycogen in the hepatocytes. It is predominantly seen in patients with longstanding type 1 diabetes mellitus and rarely reported in association with type 2 diabetes mellitus. Although it was first observed in the pediatric population, since then, it has been reported in adolescents and adults with or without ketoacidosis. The association of GH with hyperglycemia in diabetes has not been well established. One of the essential elements in the pathophysiology of development of GH is the wide fluctuation in both glucose and insulin levels. GH and non-alcoholic fatty liver disease(NAFLD) are clinically indistinguishable, and latter is more prevalent in diabetic patients and can progress to advanced liver disease and cirrhosis. Gradient dual-echo MRI can distinguish GH from NAFLD; however, GH can reliably be diagnosed only by liver biopsy. Adequate glycemic control can result in complete remission of clinical, laboratory and histological abnormalities. There has been a recent report of varying degree of liver fibrosis identified in patients with GH. Future studies are required to understand the biochemical defects underlying GH, noninvasive, rapid diagnostic tests for GH, and to assess the consequence of the fibrosis identified as severe fibrosis may progress to cirrhosis. Awareness of this entity in the medical community including specialists is low. Here we briefly reviewed the English literature on pathogenesis involved, recent progress in the evaluation, differential diagnosis, and management.Jagannath M Sherigar Joline De Castro Yong Mei Yin Debra Guss Smruti R Mohanty 2018World Journal of Hepatology2018,10,2:7
20Piperine,an active ingredient of black pepper attenuates acetaminophen-induced hepatotoxicity in mice显示文摘Objective:To explore the hepatoprotective and antioxidant effects of piperine against acetaminophen-induced hepatotoxicity in mice.Methods:In mice,hepatotoxicity was induced by a single dose of acetaminophen(900 mg/kg b.w.i.p.).Piperine(25 mg/kg b.w.i.p.) and standard drug silymarin(25 mg/kg b.w.i.p.) were given to mice,30 min after the single injection of acetaminophen.After 4 h,the mice were decapitated.Activities of liver marker enzymes [(aspartate transaminase(AST),alanine transaminase(ALT),and alkaline phosphatase(ALP)]and inflammatory mediator tumour necrosis factor-alpha(TNF-α) were estimated in serum,while lipid peroxidation and antioxidant status(superoxide dismutase,catalase,glutathione peroxidase, glutathione reductase,glutathione-s-transferase and glutathione) were determined in liver homogenate of control and experimental mice.Results:Acetaminophen induction(900 mg/kg b.w.i.p.) significantly increased the levels of liver marker enzymes,TNF-α,and lipid peroxidation,and caused the depletion of antioxidant status.Piperine and silymarin treatment to acetaminophen challenged mice resulted in decreased liver marker enzymes activity,TNF-αand lipid peroxidation levels with increase in antioxidant status.Conclusions:The results clearly demonstrate that piperine shows promising hepatoprotective effect as comparable to standard drug silymarin.Evan Prince Sabina Annie Deborah Harris Souriyan Deborah Jackline Mahaboob Khan Rasool 2010Asian Pacific Journal of Tropical Medicine2010,3,12:7
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