The interplay between non-esterified fatty acids and bovine peroxisome proliferator-activated receptors: results of an in vitro hybrid approach

Background: In dairy cows circulating non-esterified fatty acids(NEFA) increase early post-partum while liver and other tissues undergo adaptation to greater lipid metabolism, mainly regulated by peroxisome proliferator-activated receptors(PPAR). PPAR are activated by fatty acids(FA), but it remains to be demonstrated that circulating NEFA or dietary FA activate bovine PPAR. We hypothesized that circulating NEFA and dietary FA activate PPAR in dairy cows.Methods: The dose-response activation of PPAR by NEFA or dietary FA was assessed using HP300 e digital dispenser and luciferase reporter in several bovine cell types. Cells were treated with blood plasma isolated from Jersey cows before and after parturition, NEFA isolated from the blood plasma, FA released from lipoproteins using milk lipoprotein lipase(LPL), and palmitic acid(C16:0). Effect on each PPAR isotype was assessed using specific synthetic inhibitors.Results: NEFA isolated from blood serum activate PPAR linearly up to ~ 4-fold at 400 μmol/L in MAC-T cells but had cytotoxic effect. Addition of albumin to the culture media decreases cytotoxic effects of NEFA but also PPAR activation by ~ 2-fold. Treating cells with serum from peripartum cows reveals that much of the PPAR activation can be explained by the amount of NEFA in the serum(R~2 = 0.91) and that the response to serum NEFA follows a quadratic tendency, with peak activation around 1.4 mmol/L. Analysis of PPAR activation by serum in MAC-T, BFH-12 and BPAEC cells revealed that most of the activation is explained by the activity of PPARδ and PPARγ, but not PPARα. Palmitic acid activated PPAR when added in culture media or blood serum but the activation was limited to PPARδ and PPARα and the response was nil in serum from post-partum cows. The addition of LPL to the serum increased > 1.5-fold PPAR activation.Conclusion: Our results support dose-dependent activation of PPAR by circulating NEFA in bovine, specifically δand γ isotypes. Data also support the possibility of increasing PPAR activation by dietary FA;however, this nutrigenomics approach maybe only effective in pre-partum but not post-partum cows.

Analysis of an adult diabetes mellitus caused by a rare mutation of the gene:A case report

BACKGROUND This study presents the clinical and genetic mutation characteristics of an unusual case of adult-onset diabetes mellitus occurring in adolescence,featuring a unique mutation in the peroxisome proliferator-activated receptor gamma(PPARG)gene.Data Access Statement:Research data supporting this publication are available from the NN repository at www.NNN.org/download/.CASE SUMMARY The methodology employed entailed meticulous collection of comprehensive clinical data from the probands and their respective family members.Additionally,high-throughput sequencing was conducted to analyze the PPARG genes of the patient,her siblings,and their offspring.The results of this investigation revealed that the patient initially exhibited elevated blood glucose levels during pregnancy,accompanied by insulin resistance and hypertriglyceridemia.Furthermore,these strains displayed increased susceptibility to diabetic kidney disease without any discernible aggregation patterns.The results from the gene detection process demonstrated a heterozygous mutation of guanine(G)at position 284 in the coding region of exon 2 of PPARG,which replaced the base adenine(A)(exon2c.284A>Gp.Tyr95Cys).This missense mutation resulted in the substitution of tyrosine with cysteine at the 95th position of the translated protein.Notably,both of her siblings harbored a nucleotide heterozygous variation at the same site,and both were diagnosed with diabetes.CONCLUSION The PPARG gene mutation,particularly the p.Tyr95Cys mutation,may represent a newly identified subtype of maturity-onset diabetes of the young.This subtype is characterized by insulin resistance and lipid metabolism disorders.

Conjugated linoleic acid isomers and their precursor fatty acids regulate peroxisome proliferator-activated receptor subtypes and major peroxisome proliferator responsive element-bearing target genes in HepG2 cell model

The purpose of this study was to examine the induction profiles （as judged by quantitative reverse tran- scription polymerase chain reaction （qRT-PCR）） of peroxisome proliferator-activated receptor （PPAR） α,β, y subtypes and major PPAR-target genes bearing a functional peroxisome proliferator responsive element （PPRE） in HepG2 cell model upon feeding with cis-9,trans-11-octadecadienoic acid （9-CLA） or trans-10,cis-12-octadecadienoic acid （10-CLA） or their precursor fatty acids （FAs）. HepG2 cells were treated with 100 pmol/L 9-CLA or 10-CLA or their precursor FAs, viz., oleic, linoleic, and trans-11-vaccenic acids against bezafibrate control to evaluate the induc- tion/expression profiles of PPAR （α, β, γ subtypes and major PPAR-target genes bearing a functional PPRE, i.e., fatty acid transporter （FAT）, glucose transporter-2 （GLUT-2）, liver-type FA binding protein （L-FABP）, acyl CoA oxidase-1 （ACOX-1）, and peroxisomal bifunctional enzyme （PBE） with reference to β-actin as house keeping gene. Of the three housekeeping genes （glyceraldehyde 3-phosphate dehydrogenase （GAPDH）, β-actin, and ubiquitin）, β-actin was found to be stable. Dimethyl sulfoxide （DMSO）, the common solubilizer of agonists, showed a significantly higher induction of genes analyzed, qRT-PCR profiles of CLAs and their precursor FAs clearly showed upregulation of FAT, GLUT-2, and L-FABP （-0.5-.0-fold）. Compared to 10-CLA, 9-CLA decreased the induction of the FA metabolizing gene ACOX-1 less than did PBE, while 10-CLA decreased the induction of PBE less than did ACOX-I. Both CLAs and precursor FAs upregulated PPRE-beadng genes, but with comparatively less or marginal activation of PPAR subtypes This indicates that the binding of CLAs and their precursor FAs to PPAR subtypes results in PPAR activation, thereby induction of the target transporter genes coupled with downstream lipid metabolising genes such as ACOX-1 and PBE. To sum up, the expression profiles of these candidate genes showed that CLAs and their precursor FAs are involved in lipid signalling by modulating the PPAR a, 13, or ~ subtype for the indirect activation of the PPAR-target genes, which may in turn be responsible for the supposed health effects of CLA, and that care should be taken while calculating the actual fold induction values of candidate genes with reference to housekeeping gene and DMSO as they may impart false positive results.

Myeloid peroxisome proliferator-activated receptor α deficiency accelerates liver regeneration via IL-6/STAT3 pathway after 2/3 partial hepatectomy in mice

Background:Liver regeneration is a fundamental process for sustained body homeostasis and liver function recovery after injury.Emerging evidence demonstrates that myeloid cells play a critical role in liver regeneration by secreting cytokines and growth factors.Peroxisome proliferator-activated receptorα(PPARα),the target of clinical lipid-lowering fibrate drugs,regulates cell metabolism,proliferation,and survival.However,the role of myeloid PPARαin partial hepatectomy(PHx)-induced liver regeneration remains unknown.Methods:Myeloid-specific PPARa-deficient(Ppara^(Mye−/−))mice and the littermate controls(Ppara^(fl/fl))were subjected to sham or 2/3 PHx to induce liver regeneration.Hepatocyte proliferation and mitosis were assessed by immunohistochemical(IHC)staining for 5-bromo-2'-deoxyuridine(BrdU)and Ki67 as well as hematoxylin and eosin(H&E)staining.Macrophage and neutrophil infiltration into livers were reflected by IHC staining for galectin-3 and myeloperoxidase(MPO)as well as flow cytometry analysis.Macrophage migration ability was evaluated by transwell assay.The mRNA levels for cell cycle or inflammation-related genes were measured by quantitative real-time RT-PCR(qPCR).The protein levels of cell proliferation related protein and phosphorylated signal transducer and activator of transcription 3(STAT3)were detected by Western blotting.Results:Ppara^(Mye−/−)mice showed enhanced hepatocyte proliferation and mitosis at 32 h after PHx compared with Ppara^(fl/fl)mice,which was consistent with increased proliferating cell nuclear antigen(Pcna)mRNA and cyclinD1(CYCD1)protein levels in Ppara^(Mye−/−)mice at 32 h after PHx,indicating an accelerated liver regeneration in Ppara^(Mye−/−)mice.IHC staining showed that macrophages and neutrophils were increased in Ppara^(Mye−/−)liver at 32 h after PHx.Livers of Ppara^(Mye−/−)mice also showed an enhanced infiltration of M1 macrophages at 32 h after PHx.In vitro,Ppara-deficient bone marrow-derived macrophages(BMDMs)exhibited markedly enhanced migratory capacity and upregulated M1 genes Il6 and Tnfa but downregulated M2 gene Arg1 expressions.Furthermore,the phosphorylation of STAT3,a key transcript factor mediating IL6-promoted hepatocyte survival and proliferation,was reinforced in the liver of Ppara^(Mye−/−)mice after PHx.Conclusions:This study provides evidence that myeloid PPARαdeficiency accelerates PHx-induced liver regeneration via macrophage polarization and consequent IL-6/STAT3 activation,thus providing a potential target for manipulating liver regeneration.

Application of the back-error propagation artificial neural network(BPANN) on genetic variants in the PPAR-γ and RXR-α gene and risk of metabolic syndrome in a Chinese Han population

This study was aimed to explore the associations between the combined effects of several polymorphisms in the PPAR-γ and RXR-α gene and environmental factors with the risk of metabolic syndrome by back-error propaga- tion artificial neural network （BPANN）. We established the model based on data gathered from metabolic syndrome patients （n = 1012） and normal controls （n = 1069） by BPANN. Mean impact value （MIV） for each input variable was calculated and the sequence of factors was sorted according to their absolute MIVs. Generalized multifactor dimensionality reduction （GMDR） confirmed a joint effect of PPAR-9＂ and RXR-a based on the results from BPANN. By BPANN analysis, the sequences according to the importance of metabolic syndrome risk fac- tors were in the order of body mass index （BMI）, serum adiponectin, rs4240711, gender, rs4842194, family history of type 2 diabetes, rs2920502, physical activity, alcohol drinking, rs3856806, family history of hypertension, rs1045570, rs6537944, age, rs17817276, family history of hyperlipidemia, smoking, rs1801282 and rs3132291. However, no polymorphism was statistically significant in multiple logistic regression analysis. After controlling for environmental factors, A1, A2, B1 and B2 （rs4240711, rs4842194, rs2920502 and rs3856806） models were the best models （cross-validation consistency 10/10, P = 0.0107） with the GMDR method. In conclusion, the interaction of the PPAR-γ and RXR-α gene could play a role in susceptibility to metabolic syndrome. A more realistic model is obtained by using BPANN to screen out determinants of diseases of multiple etiologies like metabolic syndrome.

Relationship Research of PPAR-γ Gene Polymorphisms with Adiponectin and Leptin in Type 2 Diabetes Mellitus

Objective:To investigate the peroxisome proliferator-activated receptor-γ (peroxisome)in patients with type 2 diabetes mellitus.Proliferators-activated receptors-γ ,PPARs-γ (γ )gene.polymorphisms about serum lipofuscin and leptin.Methods:One humdred and twenty patients with type 2 diabetes admitted to our hospital from June 2015 to June 2018 were selected.The patients were divided into an obese group and a non-obese group of 60 patients each according to their waist circumference.A polymerase chain reaction-length polymorphism protocol was implemented in all patients to explore the PPAR-γ gene polymorphism and blood glucose,lipid,adiponectin and leptin levels were measured in both groups.Results:PPAR-γ gene polymorphisms in type 2 diabetic patients were dominated by wild-type homozygous;The levels of total cholesterol,triglyceride and LDL cholesterol in the obese group were significantly higher than those in the non-obese group,while the levels of HDL cholesterol were lower than those in the non-obese group.There is significant difference in comparison between groups(P<0.05)Those canrying the A alele had a significant lipid disorder profile and decreased adiponectin levels.Conclusions:PPAR-γ gene polymorphisms in type 2 diabetes are not significantly associated with adiponectin and leptin,and only in the obese group,the patients with the Allele A showed significant dyslipidemia and a declining trend of adiponectin levels.

Hepatic lipid homeostasis by peroxisome proliferator-activated receptor gamma 2

Peroxisome proliferator-activated receptor gamma(PPARγor PPARG)is a ligand-activated transcription factor belonging to the nuclear hormone receptor superfamily.It plays a master role in the differentiation and proliferation of adipose tissues.It has two major isoforms,PPARγ1 and PPARγ2,encoded from a single gene using two separate promoters and alternative splicing.Among them,PPARγ2 is most abundantly expressed in adipocytes and plays major adipogenic and lipogenic roles in the tissue.Furthermore,it has been shown that PPARγ2 is also expressed in the liver,specifically in hepatocytes,and its expression level positively correlates with fat accumulation induced by pathological conditions such as obesity and diabetes.Knockout of the hepatic Pparg gene ameliorates hepatic steatosis induced by diet or genetic manipulations.Transcriptional activation of Pparg in the liver induces the adipogenic program to store fatty acids in lipid droplets as observed in adipocytes.Understanding how the hepatic Pparg gene expression is regulated will help develop preventative and therapeutic treatments for non-alcoholic fatty liver disease(NAFLD).Due to the potential adverse effect of hepatic Pparg gene deletion on peripheral tissue functions,therapeutic interventions that target PPAR g for fatty liver diseases require fine-tuning of this gene's expression and transcriptional activity。

PPARγ_2基因Pro12Ala多态性与2型糖尿病及其一级亲属血脂的相关性研究

目的探讨过氧化物酶体增殖物激活受体(PPAR)γ2基因Pro12Ala多态性与2型糖尿病(T2DM)及其一级亲属血脂的相关性。方法将研究对象按WHO 1999年T2DM的诊断与分型标准分为T2DM组(156例,为T2DM患者且其家族中有血缘关系的T2DM患者≥2例)、T2DM一级亲属中正常糖耐量组即NFDR组(168例,为T2DM的一级亲属中糖耐量正常者)、无糖尿病家族史的正常糖耐量组即NC组(150例,与T2DM无血缘关系,且经口服糖耐量检测排除T2DM和糖耐量异常IGT者)。每组按体重指数(BMI)再分为肥胖组(BMI≥25kg/m2)和非肥胖组(BMI<25kg/m2)。应用聚合酶链反应-限制性内切酶片段长度多态性(PCR-RFLP)方法检测PPARγ2基因Pro12Ala多态性,比较不同基因型患者的血脂水平。结果 T2DM组患者BMI显著高于NC组(P<0.05);NC组、NFDR组、T2DM组甘油三酯(TG)依次增高,3者之间差异有统计学意义(P<0.05);胆固醇(TC)依次增高,但3者之间差异无统计学意义(P>0.05);T2DM组高密度脂蛋白胆固醇(HLD)显著低于NC组,差异有统计学意义(P<0.05);3组的低密度脂蛋白胆固醇(LDL)差异无统计学意义(P>0.05)。T2DM组PA/AA基因型患者较PP基因型患者的TG、TC、LDL高(P<0.05),其中肥胖组PA/AA基因型较PP基因型患者的TG、TC、LDL高,差异有统计学意义(P<0.05),而在非肥胖组中的差异均无统计学意义(P>0.05)。NFDR组PA/AA基因型较PP基因型中TG、TC、LDL有增高趋势,但差异无统计学意义(P>0.05),其中肥胖组中PA/AA基因型较PP基因型中TG、TC、LDL高,差异有统计学意义(P<0.05),而在非肥胖组中的差异均无统计学意义(P>0.05)。NC组PA/AA基因型与PP基因型患者的TC、TG、HDL、LDL水平差异无统计学意义(P>0.05),在NC肥胖组及NC非肥胖组中两种基因型患者的各血脂水平差异无统计学意义(P>0.05)。结论 PPARγ2基因Pro12Ala多态性与西北地区汉族T2DM及其一级亲属血脂相关,以肥胖者明显,但可能对血脂的影响甚微。

神经干细胞特异性PPARγ基因敲除小鼠模型的制备与鉴定

目的制备与鉴定神经干细胞特异性PPARγ基因敲除小鼠模型。方法将引进的2种转基因小鼠B6.PPARγloxp/loxp、B6.Nestin-Cre进行饲养并杂交繁殖,将子一代小鼠与B6.PPARγloxp/loxp小鼠回交获得子二代小鼠,提取子二代小鼠的基因组DNA,利用PCR方法扩增Cre和loxp基因片段,并进行琼脂糖凝胶电泳检测。选取基因型为B6.PPARγloxp/loxp.Nestin-Cre(KO)的小鼠即为神经干细胞特异性敲除PPARγ的敲除小鼠,另选基因型为B6.PPARγloxp/loxp(loxp)作为对照组小鼠。应用RT-PCR、实时荧光定量PCR方法鉴定神经干细胞特异性敲除PPARγ的敲除小鼠。结果敲除小鼠在基因鉴定时可以扩增得到PPARγloxp和Cre两个条带,在mRNA表型检测时脑内PPARγ表达显著低于对照组小鼠。成功获得神经干细胞敲除PPARγ基因的敲除小鼠。所购2种转基因小鼠均有繁殖能力,其繁殖符合孟德尔遗传规律。结论基于loxp-Cre系统成功构建神经干细胞特异性敲除PPARγ的基因敲除小鼠,为进一步的神经系统疾病的治疗及其机制研究提供模型基础。

卵形鲳鲹PPARα基因cDNA序列的克隆、组织表达及生物信息学分析

采用RACE-PCR 克隆卵形鲳鲹（Trachinotus ovatus）过氧化物酶体增殖物激活受体（peroxisome proliferator activated receptors-α,PPAR α）基因的cDNA 序列全长,并应用生物信息学方法分析其编码蛋白质的理化性质和结构特征.结果表明：卵形鲳鲹PPAR α 基因（GenBank 登录号KP893147） cDNA 全长1 930 bp,开放阅读框（ORF）为1 425 bp,共编码474 个氨基酸,其编码的蛋白质为不稳定蛋白,无信号肽和跨膜结构,二级结构由α 螺旋、β转角、伸展片段和无规则卷曲组成,且α 螺旋占较大比例;预测显示,该蛋白有PPARs 基因家族典型的DNA 结合区（DBD）和配体结合区（LBD）;序列对比表明,卵形鲳鲹PPAR α 基因与尼罗罗非鱼（Oreochromis niloticus）、花鲈（Lateolabrax japonicas）、大黄鱼（Larimichthys crocea）、金头鲷（Sparus aurata）、军曹鱼（Rachycentroncanadum）等有较高的同源性（81% - 89%）;蛋白系统进化树分析显示,在人（Homo sapiens）、鼠（Mus musculus）、鸭（Gallus gallus）、花鲈、大黄鱼、军曹鱼等动物中,卵形鲳鲹的PPAR α 蛋白与军曹鱼的进化关系最为密切（94%）,与人（68%）、鼠（68%）、鸭（67%）等的同源性较低.荧光定量分析显示,卵形鲳鲹PPAR α mRNA 在脑、肾脏、肠、脾脏等组织表达水平较高,其次是皮肤、肌肉,在心脏、肝脏中表达量较低.

Effect of Marine Collagen Peptides on Markers of Metabolic Nuclear Receptors in Type 2 Diabetic Patients with/without Hypertension

Objective To explore Effects of marine collagen peptides （MCPs） on markers of metablic nuclear receptors, i.e peroxisome proliferator-activated receptor （PPARs）, liver X receptor （LXRs） and farnesoid X receptor （FXRs） in type 2 diabetic patients with/without hypertension. Method Study population consisted of 200 type 2 diabetic patients with/without hypertension and 50 healthy subjects, all of whom were randomly assigned to MCPs-treated diabetics （n=50）, placebo-treated diabetics （n=50）, MCPs-treated diabetics with hypertension （n=50）, placebo-treated diabetics with hypertension （n=50）, and healthy controls （n=50）. MCPs or placebo （water-soluble starch） were given daily before breakfast and bedtime over three months. Levels of free fatty acid, cytochrome P450, leptin, resistin, adiponectin, bradykinin, NO, and Prostacyclin were determined before intervention, and 1.5 months, and 3 months after intervention. Hypoglycemia and the endpoint events during the study were recorded and compared among the study groups. Result At the end of the study period, MCPs-treated patients showed marked improvement compared with patients receiving placebo. The protection exerted by MCPs seemed more profound in diabetics than in diabetics with hypertension. In particular, after MCPs intervention, levels of free fatty acid, hs-CRP, resistin, Prostacyclin decreased significantly in diabetics and tended to decrease in diabetic and hypertensive patients whereas levels of cytochrome P450, leptin, NO tended to decrease in diabetics with/without hypertension. Meanwhile, levels of adiponectin and bradykinin rose markedly in diabetics following MCPs administration. Conclusion MCPs could offer protection against diabetes and hypertension by affecting levels of molecules involved in diabetic and hypertensive pathogenesis. Regulation on metabolic nuclear receptors by MCPs may be the possible underlying mechanism for its observed effects in the study. Further study into its action may shed light on development of new drugs based on bioactive peptides from marine sources.

Gut bacteria alteration in obese people and its relationshipwith gene polymorphism

AIM:To investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor γ2(PPAR-γ2) gene Pro12Ala variation in obese and normal-weight Chinese people.METHODS:Using culture methods,the amounts of Escherichia coli,Enterococci,Bacteroides,Lactobacilli,Bif idobacteria and Clostridium perfringens(C.perfringens) in the feces of 52 obese participants [body mass index(BMI):≥ 28 kg/m2] and 52 participants of normalweight(BMI:18.5-24 kg/m2) were obtained.Study participants completed comprehensive questionnaires and underwent clinical laboratory tests.The polymerase chain reaction-restriction fragment length polymorphism(PCR-PFLP) assay was used to analyze PPAR-γ2 gene Pro12Ala variation.RESULTS:The obese group exhibited a lower amount of C.perfringens(6.54 ± 0.65 vs 6.94 ± 0.57,P = 0.001)and Bacteroides(9.81 ± 0.58 vs 10.06 ± 0.39,P = 0.012) than their normal-weight counterparts.No major differences were observed in Pro12Ala genotype distribution between the two groups;however,obese individuals with a Pro/Ala genotype had a signif icantly lower level of Bacteroides(9.45 ± 0.62 vs 9.93 ± 0.51,P = 0.027) than those with a Pro/Pro genotype.In addition,the obese group demonstrated a higher stool frequency(U = 975,P < 0.001) and a looser stool(U = 1062,P = 0.015) than the normal-weight group.CONCLUSION:Our results indicated interactions among cultivable gut flora,host genetic factors and obese phenotype and this might be helpful for obesity prevention.

理脾调脂胶囊对血脂失调症大鼠及ApoE基因敲除小鼠PPARs mRNA的调控作用

目的研究理脾调脂胶囊对血脂失调症大鼠及ApoE基因敲除(ApoE-/-)小鼠PPARα、γmRNA的调控作用,探讨其调节脂质代谢的作用机制。方法 48只Wistar大鼠随机分为空白组、模型组、理脾调脂胶囊治疗组(理脾调脂组)、血脂康对照组(血脂康组),造模4周,将ApoE-/-小鼠30只随机分为空白组、血脂康组、理脾调脂组。理脾调脂组大鼠、ApoE-/-小鼠(以下简称大、小鼠)每日灌胃理脾调脂胶囊,血脂康组每日灌胃血脂康,用药8周。酶法测定大、小鼠血清总胆固醇(TC)、甘油三酯(TG)浓度,沉淀法测定大、小鼠血清高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C);内参照模板法荧光定量PCR检测大、小鼠肝脏PPARα、γmRNA的表达。结果理脾调脂组大、小鼠血清TC、TG、LDL-C浓度较模型组、空白组显著降低(P<0.01),HDL-C浓度显著提高(P<0.01),大、小鼠PPARα、γmRNA表达较模型组(或空白组)显著提高(P<0.01);与血脂康组比较,理脾调脂组大、小鼠血清TC、TG、LDL-C浓度均降低(P<0.05),HDL-C浓度均显著提高(P<0.01,P<0.05),PPARα、γmRNA表达明显提高(P<0.05)。结论理脾调脂胶囊能显著提高实验性血脂失调症大、小鼠肝脏PPARα、γmRNA的表达,具有调控核因子而影响血脂代谢的作用。

Anticancer actions of PPARγ ligands:Current state and future perspectives in human lung cancer

Peroxisome proliferator-activated receptors(PPARs) are ligand-dependent nuclear transcription factors and members of the nuclear receptor superfamily.Of the three PPARs identified to date(PPARγ,PPARβ/δ,and PPARα),PPARγ has been studied the most,in part because of the availability of PPARγagonists(also known as PPARγ ligands)and its significant effects on the management of several human diseases including type 2 diabetes,metabolic syndrome,cardiovascular disease and cancers.PPARγ is expressed in many tumors including lung cancer,and its function has been linked to the process of lung cancer development, progression and metastasis.Studies performed in gynogenic and xenograft models of lung cancer showed decreased tumor growth and metastasis in animals treated with PPARγ ligands.Furthermore,data are emerging from retrospective clinical studies that suggest a protective role for PPARγ ligands on the incidence of lung cancer.This review summarizes the research being conducted in this area and focuses on the mechanisms and potential therapeutic effects of PPARγ ligands as a novel anti-lung cancer treatment strategy.

Design,synthesis and in vitro evaluation of a series thiazolidinediones analogs as PPAR modulators

A series of thiazolidinediones analogs, as PPAR modulators, were designed, synthesized and evaluated in vitro.

LXR, PPAR<i>γ</i>, and PPAR<i>δ</i>Agonists Are Not Sufficient to Demonstrate Therapeutic Potential against Mouse Model of Systemic Lupus Erythematosus

Aim: We aimed to investigate whether the agonists for liver X receptor (LXR) ameliorate lupus-like phenotypes in mice mediated by the clearance of apoptotic cells, and compare with peroxisome proliferator-activated receptor (PPAR) γ plus PPARδ agonists, which also facilitate the clearance of apoptotic cells and exert anti-inflammatory effects in systemic lupus erythematosus (SLE). Methods: We investigated the efficacy of LXR agonist (GW3965) or dual treatment of PPARγ (pioglitazone) and PPARδ (GW0742) agonists in SLE animal models, female MRL/MpJ-Fas/J mice and BALB/cAJcl mice treated with pristane. The data were analyzed with one-way analysis of variance and Tukey’s honestly significant difference tests. Results: The treatment with LXR or PPARγ/δ agonists did not significantly alter the swelling of lymph nodes, ds-DNA production, albuminuria, histological score of glomerular lesions, and mRNA expression of target genes including Abca1, C1qa, Icam1, Mertk and Tnf. Conclusion: LXR or PPARγ/δ agonists targeting the impaired clearance for apoptosis cells may not be efficient in the remission induction therapy in SLE.

Growth Inhibiton of Human Breast Cancer Cell Line MDA-MB-231 by Rosiglitazone through Activation of PPARγ

OBJECTIVE To investigate the anti-proliferative effect of rosiglitazone and its relationship to peroxisome proliferator-activated receptor γ （PPARγ） in human breast cancer cell line MDA-MB-231 and evaluate the potential application value of rosiglitazone for breast cancer therapy. METHODS The cytostatic effect of rosiglitazone on MDA- MB-231 cells was measured by the MTT assay. Cell-cycle kinetics was assessed by flow cytometry. Apoptotic cells were determined by the TUNEL assay. MDA-MB-231 cells were treated with rosiglitazone or in combination with the PPARy antagonist GW9662 to investigate the effect of rosiglitazone on cell proliferation and its relationship to PPARγ. RESULTS The results showed that rosiglitazone could inhibit growth of MDA-MB-231 cells in a dose- and time-dependent manner with an IC50 value of 5.2 μmol/L at 24 h after the drug was added into the culture. Cell cycle analysis showed that the percentage of G0/G1 phase cells increased, S phase cells decreased, and cells were arrested in G1 phase with increasing concentrations of rosiglitazone. Detectable signs of apoptotic cell death caused by rosiglitazone occurred at a concentration of 100 μmol/L and the apoptotic rate was （18 ± 3）%. PPARγ selective antagonist GW9662 could partially reverse the inhibitory effect of rosiglitazone on proliferation of MDA-MB-231 cells. CONCLUSION It was concluded that rosiglitazone can inhibit growth of MDA-MB-231 cells via PPARy activation and a high concentration of rosiglitazone can also induce MDA-MB-231 cell apoptosis. These results suggest that PPARy represents a putative molecular target for chemopreventive therapy and rosiglitazone may be effective in the treatment of breast cancer.

Effect of mango seed kernel extract on the adipogenesis in 3T3-L1 adipocytes and in rats fed a high fat diet

Mangoes (Mangifera indica L.) are one of the most important tropical foods. The seed is one of the main by-products of mango processing. Therefore, it is important to find an economically viable use for this waste (e.g., as a food additive or supplement with high nutraceutical value). We investigated the anti-obesity effects of mango seed kernel extract with hot water (MSKE-W) in 3T3-L1 adipocytes and in a high fat diet (HFD)-induced obesity rat model. MSKE-W caused a significant decrease in the activity of glycerol 2-phosphate dehydrogenase in 3T3-L1 adipocytes without eliciting cell cytotoxicity and inhibited cellular lipid accumulation through down-regulation of transcription factors such as PPARγ and C/EBPα. In the animal model, rats fed an HFD containing 1% MSKE-W gained less weight than rats fed an HFD alone. The visceral fat mass in rats fed an HFD containing 1% MSKE-W tended to be lower than that in rats fed an HFD alone. Furthermore, histological examination of rat livers from an HFD showed steatohepatitis. However, rats on an HFD containning 1% MSKE-W showed no histopathological changes in liver tissue. Our results indicate that MSKE-W influences anti-obesity effects, both in vitro and in vivo, and suggest that MSKE-W provides a novel preventive potential against obesity.

Role of melatonin receptor 1B gene polymorphism and its effect on the regulation of glucose transport in gestational diabetes mellitus

Melatonin receptor 1B(MT2,encoded by the MTNR1B gene),a high-affinity receptor for melatonin,is associated with glucose homeostasis including glucose uptake and transport.The rs10830963 variant in the MTNR1B gene is linked to glucose metabolism disorders including gestational diabetes mellitus(GDM);however,the relationship between MT2-mediated melatonin signaling and a high birth weight of GDM infants from maternal glucose abnormality remains poorly understood.This article aims to investigate the relationship between rs10830963 variants and GDM development,as well as the effects of MT2 receptor on glucose uptake and transport in trophoblasts.TaqMan-MGB(minor groove binder)probe quantitative realtime polymerase chain reaction(qPCR)assays were used for rs10930963 genotyping.MT2 expression in the placenta of GDM and normal pregnant women was detected by immunofluorescence,western blot,and qPCR.The relationship between MT2 and glucose transporters(GLUTs)or peroxisome proliferator-activated receptorγ(PPARγ)was established by western blot,and glucose consumption of trophoblasts was measured by a glucose assay kit.The results showed that the genotype and allele frequencies of rs10830963 were significantly different between GDM and normal pregnant women(P<0.05).The fasting,1-h and 2-h plasma glucose levels of G-allele carriers were significantly higher than those of C-allele carriers(P<0.05).Besides,the protein and messenger RNA(mRNA)expression of MT2 in the placenta of GDM was significantly higher than that of normal pregnant women(P<0.05).Melatonin could stimulate glucose uptake and GLUT4 and PPARγprotein expression in trophoblasts,which could be attenuated by MT2 receptor knockdown.In conclusion,the rs10830963 variant was associated with an increased risk of GDM.The MT2 receptor is essential for melatonin to raise glucose uptake and transport,which may be mediated by PPARγ.

脓毒症研究新进展

脓毒症正逐渐成为全世界严峻的医学问题，脓毒症的发病率与病死率逐年上升，然而脓毒症的临床治疗并未取得理想的效果，可能归咎于其复杂的病理生理过程和尚未完全揭示的发病机制。近年来研究发现，氧化还原反应失衡、过氧化物酶增生物激活受体的功能下降、补体的激活与释放、神经调节紊乱、免疫麻痹等参与了脓毒症的发病机制，有助于我们对脓毒症的进一步认识。至此，本文将对这些新机制加以综述。