This study aimed to explore the effect of miR-23b-3p on the differentiation of goat intramuscular preadipocytes, and to confirm whether miR-23b-3p plays its roles via targeting the PDE4B gene. Based on the pre-transcriptome sequencing data obtained previously, the miR-23b-3p, which was differentially expressed in goat intramuscular adipocytes before and after differentiation, was used as an entry point. real-time quantitative-polymerase chain reaction (qPCR) was used to detect the expression pattern of miR-23b-3p during the differentiation of goat intramuscular preadipocytes. The effects of miR-23b-3p on adipose differentiation and adipose differentiation marker genes were determined at the morphological and molecular levels. The downstream target genes of miR-23b-3p were determined using bioinformatics prediction as well as dual luciferase reporter assay to clarify the targeting relationship between miR-23b-3p and the predicted target genes. The results indicated that overexpression of miR-23b-3p reduced lipid droplet accumulation in goat intramuscular adipocytes, significantly down-regulated the expression levels of adipogenic marker genes AP2, C/EBPα, FASN, and LPL (P < 0.01). In addition, the expressions of C/EBPβ, DGAT2, GLUT4 and PPARγ were significantly downregulated (P < 0.05). After interfering with the expression of miR-23b-3p, lipid droplet accumulation was increased in goat intramuscular adipocytes. The expression levels of ACC, ATGL, AP2, DGAT2, GLUT4, FASN and SREBP1 were extremely significantly up-regulated (P < 0.01), and the expression levels of C/EBPβ, LPL and PPARγ were significantly up-regulated (P < 0.05). It was predicted that PDE4B might be a target gene of miR-23b-3p. The mRNA expression level of PDE4B was significantly decreased after overexpression of miR-23b-3p (P < 0.01), and the interference with miR-23b-3p significantly increased the mRNA level of PDE4B (P < 0.05). The dual luciferase reporter assay indicated that miR-23b-3p had a targeting relationship with PDE4B gene. MiR-23b-3p regulates the differentiation of goat intramuscular preadipocytes by targeting the PDE4B gene.
Animals ; MicroRNAs/metabolism* ; Goats/genetics* ; PPAR gamma/metabolism* ; Adipogenesis/genetics* ; Cell Differentiation/genetics* ; Luciferases ; RNA, Messenger

OBJECTIVETo investigate the effects of rapamycin on cholesterol homeostasis and secretory function of 3T3-L1 cells.

METHODSThe in vitro cultured 3T3-L1 cells (preadipocytes) were divided into control group, rapamycin 50 nmol/L group, rapamycin 100 nmol/L group, and rapamycin 200 nmol/L group. Intracellular cholesterol level was measured by oil red O staining and high performance liquid chromatography. The secretion levels of leptin and adiponectin were assayed by enzyme-linked immunosorbent assay. The mRNA and protein expressions of peroxisome proliferator-activated receptor (PPARgamma) were assayed by quantitative real-time polymerase chain reaction and Western blot.

RESULTSOil red O staining showed rapamycin down-regulated 3T3-L1 cells differentiation and lipid accumulation. Quantitative measurement of cholesterol with high performance liquid chromatography showed that the concentrations of free cholesterol in rapamycin treatment groups had a significant reduction. The concentrations of free cholesterol in the control group, rapamycin 50 nmol/L group, rapamycin 100 nmol/L group, and rapamycin 200 nmol/L group were (12.89 +/- 0.16), (9.84 +/- 0.45), (9.39 +/- 0.46), and (8.61 +/- 0.34) mg/ml, respectively (P < 0.05), and the concentrations of total cholesterol were (12.91 +/- 0.50), (9.94 +/- 0.96), (10.45 +/- 2.51), and (9.53 +/- 0.63) mg/ml, respectively. The leptin concentrations in the control group, rapamycin 50 nmol/L group, rapamycin 100 nmol/L group, and rapamycin 200 nmol/L group were (19.02 +/- 0.52), (16.98 +/- 0.11), (15.62 +/- 0.01), and (13.84 +/- 0.66) ng/ml, respectively. The mRNA expressions of PPARgamma in the rapamycin 50 nmol/L group, rapamycin 100 nmol/L group, and rapamycin 200 nmol/L group were significantly lower than that in control group (P < 0.05). The protein expressions of PPARgamma in the rapamycin 50 nmol/L group, rapamycin 100 nmol/L group, and rapamycin 200 nmol/L group were 80%, 74%, and 61% of that in control group (P < 0.05). After the cells were treated with rapamycin 100 nmol/L, PPARgamma blocking agent GW9662 10 micromol/L, and PPARgamma agonist troglitazone 10 micromol/L, respectively, for 96 hours, the mRNA expression of PPARgamma was (0.60 +/- 0.14), (0.67 +/- 0.03), and (1.30 +/- 0.14) of that in control group (P < 0.05). The protein expression showed a similar trend with mRNA expression (P < 0.05). After the cells were treated with rapamycin 100 nmol/L, PPARgamma blocking agent GW9662 10 micromol/L, and PPARgamma agonist troglitazone 10 micromol/L, respectively, for 96 hours, the expression of leptin in the control group, rapamycin 50 nmol/L group, rapamycin 100 nmol/L group, and rapamycin 200 nmol/L group was (19.02 +/- 0.52), (15.62 +/- 0.10), and (14.45 +/- 1.01) and (18.07 +/- 0.66) ng/ml, respectively (P < 0.05 compared with the control group).

CONCLUSIONSBy downregulating the expression of PPARgamma, rapamycin can decrease cholesterol accumulation in 3T3-L1 cells and inhibit its leptin-secreting capability. This finding may provide a possible explanation for rapamycin-induced hyperlipidemia in clinical practice.

3T3-L1 Cells ; Adipocytes ; drug effects ; metabolism ; Animals ; Cholesterol ; metabolism ; Leptin ; metabolism ; Mice ; PPAR gamma ; genetics ; metabolism ; Sirolimus ; pharmacology

BACKGROUNDMicroRNAs (miRNAs) function as essential posttranscriptional modulators of gene expression, and are involved in a wide range of physiologic and pathologic states, including cancer. Numerous miRNAs are deregulated in hepatocellular carcinoma (HCC). This study aimed to investigate the role of miR-27a in the development of HCC.

METHODSThe expression of MiR-27a was measured by quantitative real-time polymerase chain reaction (qRT-PCR). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide was used to examine changes in the viability of HepG2, Bel-7402, Bel-7404 hepatoma cell lines associated with up-regulation or down-regulation of miR-27a. A dual-luciferase activity assay was used to verify a target gene of miR-27a. Immunohistochemistry, qRT-PCR, Western blotting analysis, and cell cycle and apoptosis flow cytometric assays were used to elucidate the mechanism by which miR-27a modulates liver cancer cell proliferation.

RESULTSThe expression of miR-27a was significantly increased in HCC tissues and HepG2, Bel-7402, Bel-7404 hepatoma cell lines (P < 0.05). We also found that the down-regulation of miR-27a in HepG2 cells dramatically inhibited proliferation, blocked the G1 to S cell cycle transition and induced apoptosis (P < 0.05). In addition, miR-27a directly targeted the 3'- untranslated region of peroxisome proliferator-activated receptor &gamma; (PPAR-&gamma;), and ectopic miR-27a expression suppressed PPAR-&gamma; expression on the mRNA and protein levels. The rosiglitazone-induced overexpression of PPAR-&gamma; attenuated the effect of miR-27a in HCC cells.

CONCLUSIONSOur findings suggested that miRNA-27a promoted HCC cell proliferation by regulating PPAR-&gamma; expression. MiR-27a may provide a potential therapeutic strategy for HCC treatment.

Carcinoma, Hepatocellular ; genetics ; metabolism ; Cell Proliferation ; genetics ; physiology ; Gene Expression Regulation, Neoplastic ; Hep G2 Cells ; Humans ; Liver Neoplasms ; genetics ; metabolism ; MicroRNAs ; genetics ; physiology ; PPAR gamma ; metabolism

OBJECTIVETo study the effects of Tongxinluo on the expressions of matrix metalloproteinase-3 (MMP-3), MMP-9 and peroxisome proliferators-activated receptor gamma (PPARgamma) in atherosclerotic rabbits and explore the mechanism of its anti-atherosclerotic effect.

METHODSTwenty-four rabbits were randomized equally into control group, atherosclerotic model group (fed with high-fat diet for 14 weeks) and Tongxinluo group. The expressions of MMP-3, 9 and PPARgamma in the 3 groups were observed by means of immunohistochemistry.

RESULTSThe expressions of MMP-3, 9 and PPARgamma in the model group and Tongxinluo group were significantly higher than those in the control group (P<0.01). After high-fat diet feeding for 14 weeks, Tongxinluo group showed significantly lower expressions of MMP-3 and 9 but higher expression of PPARgamma than the model group (P<0.01).

CONCLUSIONTongxinluo can inhibit the expression of MMP-3 and 9 and increase the expression of PPARgamma, which might be the mechanism of its anti-atherosclerotic effect.

Animals ; Atherosclerosis ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Male ; Matrix Metalloproteinase 3 ; genetics ; metabolism ; Matrix Metalloproteinase 9 ; genetics ; metabolism ; PPAR gamma ; genetics ; metabolism ; Rabbits ; Random Allocation

OBJECTIVETo study the effect of peroxisome proliferators activated receptors (PPAR) alpha, gamma ligand on ATP-binding cassette transporter A1 (ABCA1) and caveolin-1 expressions and cholesterol, ox-LDL contents in human monocyte derived foam cells.

METHODMalondialdehyde (MDA) was measured by TBARS method, ox-LDL detected by ELISA method, cholesterol measured by fluorescence spectrophotometric method, ABCA1, caveolin-1 mRNA and protein expressions determined by RT-PCR and Western blot, in human monocytes, foam cells [human monocyte-derived macrophage induced by myristate acetate (PMA) further treated with 50 mg/L ox-LDL for 24 h], foam cells plus 10 micromol/L pioglitazone for 48 h, foam cells plus 5 micromol/L clofibrate for 48 h.

RESULTThe intracellular total cholesterol (TC), free cholesterol (FC), cholesteryl ester (CE), ox-LDL and lipid peroxide were significantly increased and the membrane expressions of ABCA1, caveolin-1 were down-regulated in foam cells compared to monocytes (all P < 0.05) and these changes were significantly attenuated by cotreatment with PPARalpha, gamma ligand.

CONCLUSIONThe anti-atherosclerosis effects of PPARalpha, gamma ligand are related to reducing cholesterol contents and up-regulating ABCA1, caveolin-1 expressions in foam cells.

ATP Binding Cassette Transporter 1 ; ATP-Binding Cassette Transporters ; metabolism ; Caveolin 1 ; metabolism ; Cell Line ; Cholesterol ; genetics ; metabolism ; Foam Cells ; metabolism ; Gene Expression ; Humans ; Malondialdehyde ; metabolism ; Monocytes ; metabolism ; PPAR alpha ; metabolism ; PPAR gamma ; metabolism

OBJECTIVETo explore the relation of phlegm-stasis syndrome with insulin resistance and monocyte peroxisome proliferator activated receptor-gamma messenger ribonucleic acid (PPARgamma mRNA) expression in patients with coronary heart disease (CHD).

METHODSSixty patients with CHD were differentiated into three syndrome types, the non-phlegm non-stasis (NN) type, the phlegm congealing heart vessel (PC) type and the phlegm-stasis cemented (PS) type. Besides, 20 healthy volunteers were selected as the normal control. Levels of fasting plasma glucose (FPG) and fasting insulin (FINS) were determined and homeostasis model assessment of insulin resistance (HOMA-IR) was calculated accordingly. The expression of PPARgamma mRNA in the peripheral monocytes was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTSLevels of FINS, HOMA-IR and PPAR-gamma mRNA expression in all CHD patients were higher than in the normal control (P <0.01, P < 0.05); comparisons of the three indexes between patients of different syndrome types showed that they were higher in PC type and PS type than in NN type (P < 0.05 or P <0.01), and the difference between PC type and PS type was significant (P < 0.05).

CONCLUSIONChanges of insulin resistance and PPARgamma mRNA expression in monocytes are possibly one of the mechanisms for the development of phlegm-stasis syndrome in CHD.

Aged ; Case-Control Studies ; Coronary Disease ; genetics ; metabolism ; Female ; Humans ; Insulin Resistance ; Male ; Middle Aged ; Monocytes ; metabolism ; PPAR gamma ; genetics ; metabolism ; RNA, Messenger ; metabolism

OBJECTIVETo study the effect of beta3 adrenergic receptor (beta3AR) Trp64Arg and peroxisome proliferator activated receptor gamma 2 (PPARgamma2) Prol2Ala polymorphisms on insulin resistance.

METHODSOne hundred and eight dizygotic twin pairs were enrolled in this study. Microsatellite polymorphism was used to diagnose zygosity of twins. Insulin sensitivity was estimated with logarithm transformed homeostasis model assessment (HOMA). PCR-RFLP analysis was performed to detect the variants. As a supplement to the sib-pair method, identity by state (IBS) was used to analyze the association of polymorphisms with insulin sensitivity.

RESULTSThe genotype frequencies of Trp64Trg, Trp64Arg, and Arg64Arg were 72.3%, 23.8%, and 3.9%, respectively, while the genotype frequencies of Prol2Pro, Prol2Ala, and Alal2Ala were 89.9%, 9.6%, and 0.5%, respectively. For beta3AR Trp64Arg the interclass co-twin correlations of Waist-to-hip ratio (WHR), blood glucose (GLU), and insulin (INS), homeostasis model assessment insulin resistance index (HOMA-IR) of the twin pairs sharing 2 alleles of IBS were greater than those sharing 0-1 allele of IBS, and HOMA-IR had statistic significance. For PPARgamma2 Pro12Ala most traits of twin pairs sharing 2 alleles of IBS had greater correlations and statistic significance in body mass index (BMI), WHR, percent of body fat (PBF) and GLU, but there were low correlations of either insulin or HOMA-IR of twin pairs sharing 1 or 2 alleles of IBS. The combined effects of the two variations showed less squared significant twin-pair differences of INS and HOMA-IR among twins sharing 4 alleles of IBS.

CONCLUSIONSBeta3AR Trp64Arg and PPARgamma2 Pro12Ala polymorphisms might be associated with insulin resistance and obesity, and there might be slight synergistic effects between this two gene loci, and further studies are necessary to confirm this finding.

Adolescent ; Child ; Child, Preschool ; Genotype ; Humans ; Insulin Resistance ; genetics ; Obesity ; genetics ; PPAR gamma ; genetics ; Polymorphism, Genetic ; Receptors, Adrenergic, beta-3 ; genetics ; Twins, Dizygotic ; genetics ; metabolism

OBJECTIVETo explore if PPARgamma agonist rosiglitazone could enhance the anti-atherosclerotic effects of mouse peroxisome proliferator-activated receptor gamma1 (PPARgamma1) gene transfer in apolipoprotein-knock out mice.

METHODSAdult ApoE-knock out mice were fed a Western-diet for 20-weeks and then injected with PBS, Ad. PPARgamma1 (5 x 10(8)pfu) or Ad. GFP (5 x 10(8)pfu) via jugular vein. Another group of mice were intervened with rosiglitazone (dissolved in 0.5% cellulose acetate, 4 mg.kg(-1).d(-1), per gavage) 1 week before Ad. PPARgamma1 injection (n = 10, each group). Two weeks later, the lipid core and plaque composition were characterized with oil red O staining and Movat method respectively. The expression of PPARgamma, SM-actin, MOMA-2, MMP-9/TIMP-1, CD40/CD40L and TF antigens in aortic roots and plaques among four groups were compared semi-quantitatively using immunohistochemical technology.

RESULTSAll parameters were similar between AdGFP and PBS groups (P > 0.05). The area of plaque were significantly decreased and oil red O staining area significantly increased in AdPPARgamma1 [(0.86 +/- 0.12) mm(2), (150 +/- 35) x 10(3) microm(2)] and AdPPARgamma1 + RO [(0.79 +/- 0.15) mm(2), (270 +/- 49) x 10(3) microm(2)] treated mice compared with AdGFP group [(0.98 +/- 0.17) mm(2), (80 +/- 21) x 10(3) microm(2)] all P < 0.05. Elastic fiber, collagen and proteoglycan in plaques were also significantly increased in AdPPARgamma1 and AdPPARgamma1 + RO groups. Upregulation of PPARgamma, SM-actin, TIMP-1 antigen activity and downregulation of MOMA-2, MMP-9, CD40/CD40L and TF antigen activity in AdPPARgamma1 and most significantly in AdPPARgamma1 + RO group were observed (P < 0.05).

CONCLUSIONAnti-atherosclerotic effects of PPARgamma1 gene transfer in ApoE-knock out mice could be enhanced by PPARgamma agonist rosiglitazone.

Animals ; Apolipoproteins E ; deficiency ; genetics ; Atherosclerosis ; genetics ; Gene Transfer Techniques ; Male ; Mice ; Mice, Knockout ; PPAR gamma ; agonists ; genetics ; metabolism ; Peroxisome Proliferator-Activated Receptors ; metabolism ; Thiazolidinediones ; pharmacology ; Transfection

OBJECTIVETo investigate the changes of NF-kappa B binding activity, the expression of PPARr and their correlation in the liver of rats with fatty liver disease (FLD) induced by different pathogenic factors and to investigate the molecular mechanism of the inflammation in FLD.

METHODS40 Wistar rats were randomly divided into 4 groups of ten each: normal group, alcohol group, fat-rich diet group, alcohol adding fat-rich diet group. The rats were sacrificed at the end of the 16th week from the starting day of the experiment. Serum and liver specimens were collected. Histological specimens were stained with HE, SudanIV, and Masson and then studied microscopically. The ultrastructural changes were also checked under an electron microscope. NF-kappa B binding activity and the expression of PPARr mRNA were determined by electrophoretic mobility shift assay (EMSA) and RT-PCR respectively. The correlations between NF-kappa B binding activity and the expression of PPARr and the biochemical indexes were analyzed.

RESULTSSteatosis, inflammation, necrosis and fibrosis were present in livers of the rats of all the experimental groups, and were most severe in the alcohol adding fat-rich diet group. NF-kappa B binding activity was markedly increased in the livers of the alcohol group (142+/-16.32) and of the alcohol adding fat-rich diet group (238+/-19.14) in comparison to the livers of the normal (73+/-9.24, F = 6.36, 17.93) and those of the fat-rich diet group (84+/-10.38, F = 5.96, 16.20). Binding activity was higher in the alcohol adding fat-rich diet group than that in the simple alcohol group, but there was no difference between those of the fat-rich diet and normal groups. The level of PPARr mRNA was lower in the livers of the alcohol, fat-rich diet, alcohol adding fat-rich diet groups (0.2530+/-0.069, 0.3647+/-0.082, 0.1226+/-0.054) than that of the controls (0.8097+/-0.094) (F = 15.43, 7.24, 21.45). NF-kappa B binding activity was correlated positively with the level of serum TNF alpha (r = 0.527, 0.639) and the content of MDA in the liver homogenates (r = 0.723, 0.537), but negatively with the expression of PPARr in the livers of the alcohol and the alcohol adding fat-rich diet groups (r = -0.568, -0.891).

CONCLUSIONThe enhanced nuclear factors NF-kappa B binding activity and decreased expression of PPARr play a pivotal role in the inflammatory response of FLD induced by alcohol and fat-rich diet. It may provide a new idea for treating FLD effectively.

Animals ; Fatty Liver ; metabolism ; Liver ; metabolism ; Male ; NF-kappa B ; metabolism ; PPAR gamma ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Wistar

OBJECTIVETo investigate the effect of PPARgamma1 gene overexpression on caveolin-1 mRNA and protein expressions in a murine macrophage cell line Raw264.7.

METHODSReplication-deficient recombinant adenovirus expression vector of PPARgamma1 was constructed using the AdEasy system. Raw264.7 cells were randomly treated as follows: P group (PPARgamma1 gene overexpression), T group (Troglitazone 40 micromol/L in DMSO), PT group (PPARgamma1 gene overexpression and Troglitazone) and control group. Changes of PPARgamma1 and caveolin-1 at mRNA and protein levels were investigated.

RESULTSCaveolin-1 expression can be detected by RT-PCR in Raw264.7, by immunocytochemistry method in cell and nuclear membrane but not by immunoblotting at protein level. Caveolin-1 expression at mRNA and protein levels in Raw264.7 were significantly higher in P, T and PT groups compared to control group and the expression was also significantly higher in PT group than that in P group and T group (P < 0.05). PPARgamma expression was significantly increased in PT group and P group where remained unchanged in T group compared to control group.

CONCLUSIONPPARgamma1 overexpression can upregulate caveolin-1 expression in macrophages. Troglitazone upregulated caveolin-1 expression in the absence of increased PPARgamma1 expressions at mRNA and protein levels.

Adenoviridae ; genetics ; Animals ; Caveolin 1 ; metabolism ; Cell Line ; Chromans ; pharmacology ; Gene Expression ; Macrophages ; drug effects ; metabolism ; Mice ; PPAR gamma ; genetics ; RNA, Messenger ; metabolism ; Thiazolidinediones ; pharmacology