Retinopathy is a major cause of morbidity in diabetes and remains the primary cause of new blindness. Therefore, it is necessary to find new drug to treat diabetic retinopathy. Type 2 diabetes mellitus (T2DM) rats were induced by injection (ip) with streptozotocin (STZ) 35 mg x kg(-1) and fed with a high-carbohydrate/high-fat diet 2 weeks later. From week 17 to 32, diabetic rats were given different doses of berberine 75, 150, and 300 mg x kg(-1), fenofibrate 100 mg x kg(-1) and rosiglitazone 4 mg x kg(-1), separately. Retinal structure was observed with hematoxylin-eosin staining and peroxisome proliferator-activated receptors (PPARs) alpha/delta/gamma protein expressions were detected by immunohistochemistry. The retina of control rats was thicker than that of other groups, 16 weeks treatment with berberine (150 and 300 mg x kg(-1)) and rosiglitazone 4 mg x kg(-1) thickened the diabetic retina, but no difference existed in retinal structure among groups. Both berberine (150 and 300 mg x kg(-1)) and rosiglitazone 4 mg x kg(-1) significantly decreased PPARy expression in diabetic retina; while berberine (150 and 300 mg x kg(-1)) and fenofibrate 100 mg x kg(-1) obviously increased both PPARalpha and PPARdelta expressions in diabetic retina. Berberine modulates PPARalpha/delta/gamma protein levels in diabetic retina which may contribute to ameliorate retinopathy complication induced by STZ and a high-carbohydrate/high-fat diet. It is expected that berberine might be a more beneficial drug to treat diabetic retinal complication comparing with fenofibrate and rosiglitazone.
Animals ; Berberine ; pharmacology ; Diabetes Mellitus, Experimental ; metabolism ; Diabetes Mellitus, Type 2 ; metabolism ; Diabetic Retinopathy ; metabolism ; Fenofibrate ; pharmacology ; Hypoglycemic Agents ; pharmacology ; Male ; PPAR alpha ; metabolism ; PPAR delta ; metabolism ; PPAR gamma ; metabolism ; Rats ; Rats, Wistar ; Retina ; metabolism ; pathology ; Thiazolidinediones ; pharmacology

A series of tetrahydroisoquinoline derivatives were prepared and their peroxisome proliferator-activated receptor (PPAR) alpha/gamma agonistic activities were evaluated to obtain more potent PPAR agonist. All of them were new compounds, and their structures were confirmed by 1H NMR and HR-MS. Three compounds exhibited higher agonistic activities of PPARgamma than that of the comparison, six compounds exhibited higher agonistic activities of PPARalpha than that of the comparison, and compound 8a was discovered as a highly potent PPARalpha/gamma agonist that is much more active than that of WY14643 and rosiglitazone. The development of potent PPAR agonists may offer a new choice for the treatment of diabetes.
Drug Design ; HEK293 Cells ; Humans ; Hypoglycemic Agents ; chemical synthesis ; chemistry ; pharmacology ; PPAR alpha ; agonists ; metabolism ; PPAR gamma ; agonists ; metabolism ; Structure-Activity Relationship ; Tetrahydroisoquinolines ; chemical synthesis ; chemistry ; pharmacology ; Transfection

OBJECTIVETo investigate the effects of peroxisome proliferator activated receptor-alpha (PPAR-a) activation on oleic acid (OA)-induced steatosis and hepatic expression of heme oxygenase-1 (HO-1) using an in vitro cell model system.

METHODSA steatosis human hepatocyte in vitro model system was established by treating HepG2 cells with 0.2 mmol/L of oleic acid for 24 hours. The steatosis cells were then divided into four groups for an additional 24 hours of treatment with 0.2 mmol/L of oleic acid alone (model control group) or with 5, 10 or 50 pnol/L of fenofibrate (FF, a selective PPAR-a agonist; experimental groups). Untreated HepG2 cells served as non-steatosis controls. Effect of PPAR-a activation on fat accumulation was detected by Oil Red O staining and on intracellular triglyceride (TG) levels by enzymatic assay. mRNA and protein expression of PPAR-alpha and HO-1 were quantified by real-time PCR and immunocytochemistry, respectively. One-way ANOVA and the LSD t-test were used for between-group comparisons, and correlation analysis was performed with the Pearson's correlation coefficient.

RESULTSThe steatosis model control cells showed significantly increased TG deposition (379.98 +/- 23.19 mg/g protein, vs. non-steatosis controls F = 148.56, P< 0.01), significantly decreased mRNA and protein expression of PPAR-alpha (0.42 +/- 0.38,F= 177.64,P< 0.01 and 0.47 +/- 0.14, F= 120.76,P< 0.01) and HO-1 (0.36 +/- 0.66, F= 74.77,P< 0.01 and 0.26 +/- 0.10,F= 119.90,P<0.01). FF (5, 10 and 50 micromol/L) inhibited the steatosis induced by OA in a concentration-dependent manner (294.00 +/- 19.80, 250.33 +/- 9.96, and 196.99 +/- 9.14, F = 148.56, P <0.01) and increased the mRNA and protein expression of PPAR-alpha (0.55 +/- 0.65, 0.85 +/- 0.61, and 1.31 +/- 0.36,F= 177.64,P< 0.01; 0.82 + 0.11, 1.31 +/- 0.16, and 1.75 +/- 0.13, F= 120.76,P <0.01) and HO-1 (0.62 +/- 0.05, 0.84 +/- 0.07, and 1.30 +/- 0.11,F= 74.77,P <0.01; 0.44 +/- 0.08, 0.81 +/- 0.08, 1.20 +/- 0.10,F= 119.90,P< 0.01).

CONCLUSIONActivation of PPAR-a prevents OA-induced steatosis in HepG2 cells, and HO-1 may function as a downstream effector of this mechanism.

Fatty Liver ; chemically induced ; Heme Oxygenase-1 ; metabolism ; Hep G2 Cells ; Humans ; Oleic Acid ; pharmacology ; PPAR alpha ; metabolism ; Triglycerides ; metabolism

Endogenously eliminating the hematoma is a favorable strategy in addressing intracerebral hemorrhage (ICH). This study sought to determine the role of retinoid X receptor-α (RXR-α) in the context of hematoma absorption after ICH. Our results showed that pharmacologically activating RXR-α with bexarotene significantly accelerated hematoma clearance and alleviated neurological dysfunction after ICH. RXR-α was expressed in microglia/macrophages, neurons, and astrocytes. Mechanistically, bexarotene promoted the nuclear translocation of RXR-α and PPAR-γ, as well as reducing neuroinflammation by modulating microglia/macrophage reprograming from the M1 into the M2 phenotype. Furthermore, all the beneficial effects of RXR-α in ICH were reversed by the PPAR-γ inhibitor GW9662. In conclusion, the pharmacological activation of RXR-α confers robust neuroprotection against ICH by accelerating hematoma clearance and repolarizing microglia/macrophages towards the M2 phenotype through PPAR-γ-related mechanisms. Our data support the notion that RXR-α might be a promising therapeutic target for ICH.
Anilides/pharmacology* ; Cerebral Hemorrhage/drug therapy* ; Hematoma/drug therapy* ; Humans ; Macrophages ; Microglia ; Neuroprotection ; PPAR gamma ; Retinoid X Receptor alpha

OBJECTIVETo explore the effects of the simultaneous activation of liver X receptor (LXR) and peroxisome proliferator-activated receptor alpha (PPARalpha) on bile acid biosynthesis in rats.

METHODSTotally 36 male SD rats were divided into three groups with 12 rats in each group: control group, high cholesterol (HC) group, and high cholesterol + fenofibrate (HC + FENO) group. Total bile acids (serum bile acids plus fecal bile acids) level was assayed. The levels of mRNA for peroxisomal palmitoyl-CoA oxidase (Acox1), LXR, cholesterol 7alpha-hydroxylase (CYP7A1), D-bifunctional protein (DBP), trihydroxycoprostanoyl-CoA oxidase (Acox2), sterol 12alpha-hydroxylase (CYP8B1), and sterol 27-hydroxylase (CYP27A1) in liver were detected by RT-PCR.

RESULTSTotal bile acid level was significantly higher in HC + FENO group than in HC group (P < 0.01), and both were significantly higher than that in control group (P < 0.01). Compared with HC group, the mRNA expression of Acox1 and DBP was significantly higher in HC + FENO group (P < 0.01), but no statistical differences was found between HC group and control group. The mRNA levels of LXR and CYP7A1 in HC + FENO group and HC group were not significantly different but were both significantly higher than that in control group (P < 0.01, P < 0.05). No changes were observed in Acox2, CYPSB1, and CYP27A1 mRNA levels among these three groups.

CONCLUSIONSimultaneous activation of LXR and PPARalpha can increase of CYP7A1 and DBP mRNA exDression and thus accelerates the biosynthesis of bile acid.

Animals ; Bile Acids and Salts ; biosynthesis ; Cholesterol ; pharmacology ; Fenofibrate ; pharmacology ; Hypolipidemic Agents ; pharmacology ; Liver ; drug effects ; enzymology ; Liver X Receptors ; Male ; Orphan Nuclear Receptors ; agonists ; PPAR alpha ; agonists ; Rats

A series of novel tetrahydrocarboline derivatives was designed and synthesized in order to discover more potent peroxisome proliferator-activated receptor (PPAR) alpha/gamma dual regulators. The structures of these compounds were confirmed by 1H NMR and HR-MS; their PPAR-regulating activities were evaluated in vitro. Compounds 6h, 6n, 6p and 6q exhibited more potent PPARalpha agonistic activities than the control drug WY14643, while compounds 60, 6g, 6i and 6q exhibited more potent PPARgamma agonistic activities than the control drug rosiglitazone. Compound 6q was discovered as a potent PPARalpha/gamma dual agonist and deserves further investigation.
Animals ; Carbolines ; chemical synthesis ; chemistry ; pharmacology ; Cells, Cultured ; Drug Design ; Hypoglycemic Agents ; chemical synthesis ; chemistry ; pharmacology ; Molecular Structure ; PPAR alpha ; agonists ; PPAR gamma ; agonists ; Peroxisome Proliferator-Activated Receptors ; agonists ; Pyrimidines ; metabolism ; Structure-Activity Relationship ; Thiazolidinediones ; metabolism ; Transfection

OBJECTIVETo investigate the effects of atorvastatin on angiotensin II (Ang II)-induced hypertrophy of cardiac myocytes (MC) and the changes of mRNA expression of peroxisome proliferators-activated receptor alpha, gamma (PPAR alpha, gamma) subtypes in vitro.

METHODSHypertrophy in neonatal rat MC was established with Ang II and treated with atorvastatin. The surface area of MC was analyzed by the aid of NIH Image J software, and the synthetic rate of protein in MC was detected by (3)H-leucine incorporation. mRNA expression of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), matrix metalloproteinase (MMP) 9, MMP2, interleukin1beta (IL-1beta) and PPARalpha, gamma was measured by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSChanges of MC were detected induced by Ang II, including increases in surface area, mRNA expression of ANP, BNP, MMP9, MMP2 and IL-1beta, and (3)H-leucine incorporation, as well as a decrease in mRNA expression of PPARalpha, gamma. Treatment with atorvastatin inhibited the changes above in a dose-dependent manner, but no change was found in treated with DMSO.

CONCLUSIONAtorvastatin inhibits cardiac hypertrophy in vitro. It is suggested that atorvastatin has a potential role in the prevention and treatment of cardiac diseases such as cardiac hypertrophy, and PPAR alpha and gamma maybe involved in this process.

Angiotensin II ; Animals ; Atorvastatin Calcium ; Cardiomegaly ; metabolism ; Cells, Cultured ; Gene Expression Regulation ; Heptanoic Acids ; pharmacology ; Myocytes, Cardiac ; drug effects ; metabolism ; PPAR alpha ; metabolism ; PPAR-beta ; metabolism ; Pyrroles ; pharmacology ; Rats ; Rats, Wistar ; Up-Regulation

Tea is a popular beverage. Recently, green tea was reported to increase the number of peroxisomes in rats. In this study, to find out whether the green tea-induced proliferation of peroxisomes is mediated by PPARalpha , a transient transfection assay was carried out to investigate the interactions of tea extracts (green tea, black tea,oolong tea and doongule tea) and tea components (epigallocatechin gallate, epigallocatechin, epicatechin gallate, epicatechin and gallic acid), with mouse cloned PPARalpha . Green tea and black tea extracts, and epigallocatechin gallate, a major component of fresh green tea leaves, increased the activation of PPAalpha 1.5-2 times compared with the control. It is suggested that the green tea induced-peroxisomal proliferation may be mediated through the transactivation of PPARalpha and that epigallocatechin gallate may be an effective component of green tea leaves. This would account for the increase in the number of peroxisomes and the activity of peroxisomal enzymes previously reported. However, black tea, a fully fermented product, had a stronger effect than oolong tea extract. These results also suggest, that in addition to epigallocatechin gallate, green tea leaves may possess some active chemicals newly produced as a result of the fermentation process, which act on PPARalpha like other peroxisome proliferators.
Animals ; COS Cells/enzymology ; Camellia sinensis ; Catechin/*analogs&derivatives/pharmacology ; Cercopithecus aethiops ; PPAR alpha/*metabolism ; Plant Extracts/*pharmacology ; Plasmids ; *Tea ; Trans-Activation (Genetics)/drug effects ; Transfection/veterinary

OBJECTIVETo investigate the effect of peroxisome proliferator-activated receptor (PPAR)&alpha; agonist bezafibrate and oxidized low density lipoprotein (ox-LDL) on fibroblast growth factor 21 (FGF21) expression and apoptosis in cardiac endothelial cells.

METHODSThe mRNA level of FGF21 was determined by real time-PCR and the protein concentration of FGF21 in culture media was detected by enzyme-linked immunosorbent assay in cultured cardiac microvascular endothelial cells (CMECs) incubated with 10, 50, 100 µg/ml ox-LDL, 50, 100 or 200 µmol/L bezafibrate alone or in combination with 100 µg/ml ox-LDL. CMECs apoptosis in various treatment groups was also determined.

RESULTSFGF21 mRNA and protein expressions were significantly upregulated in proportion to increased ox-LDL, and 200 µmol/L bezafibrate alone also significantly upregulated FGF21 expression and CMECs apoptosis was significantly reduced in 200 µmol/L bezafibrate + 100 µg/ml ox-LDL group compared to 100 µg/ml ox-LDL group (P < 0.05).

CONCLUSIONSOur data suggest that bezafibrate and ox-LDL induced upregulation of FGF21 might mediate the protective effect against apoptosis. Endogenous FGF21 could thus play important roles in improving the endothelial function at the early stage of atherosclerosis and slowing the development of coronary heart disease.

Animals ; Apoptosis ; Atherosclerosis ; metabolism ; pathology ; Bezafibrate ; pharmacology ; Cells, Cultured ; Endothelium, Vascular ; cytology ; metabolism ; Fibroblast Growth Factors ; metabolism ; Lipoproteins, LDL ; pharmacology ; PPAR alpha ; agonists ; Rats ; Rats, Wistar

This study was aimed to investigate the influence of PPARalpha agonist on the expression of TF (tissue factor) in THP-1 cells. THP-1 cells were pretreated with different concentrations of PPARalpha agonist (fenofibrate) for definite time. Lipopolysaccharide (LPS)-induced TF mRNA and protein levels were detected by RT-PCR and Western blot respectively. The results showed that fenofibrate decreased tissue factor protein and mRNA expression in supernatants of LPS-stimulated human monocytes in a concentration-dependent manner (P < 0.05 - 0.01, n = 5). It is concluded that fenofibrate inhibit TF expression induced by LPS in THP-1 cells, which may be involved in the anti-atherosclerotic effects of PPARalpha agonist.
Depression, Chemical ; Fenofibrate ; pharmacology ; Humans ; Leukemia, Monocytic, Acute ; metabolism ; pathology ; Lipopolysaccharides ; antagonists & inhibitors ; pharmacology ; PPAR alpha ; agonists ; RNA, Messenger ; biosynthesis ; genetics ; Thromboplastin ; biosynthesis ; genetics ; Tumor Cells, Cultured