PPARγ Protein Expression Research Articles

Effects of Emodin on Alveolar Bone Resorption via the IL-23/Th17 Inflammatory Axis in Rats with Periodontitis

This study aimed to analyze the effect of emodin on alveolar bone resorption in rats with periodontitis through the interleukin-23 (IL-23)/T helper 17 (Th17) cells inflammatory axis. Twenty-four male Sprague Dawley rats were randomly divided into the following three groups of eight rats each: the control group (group N), periodontitis group (group P), and periodontitis + emodin intervention group (group E). After 2 weeks of continuous emodin intervention, alveolar bone loss (ABL) was evaluated by morphological analysis. Tartrate-resistant acid phosphatase staining was performed to determine the number of osteoclasts (OCs) in periodontal tissue. The ABL and trabecular separation were greater and the number of OCs and the G1/G0 and G2/M phase ratios were higher in group P than those in groups N and E (P < 0.05). In contrast, the trabecular number and thickness were decreased and the S and G2+S phase ratios were lower in group P than those in groups N and E (P < 0.05). However, these indices did not differ significantly between groups E and N. The IL-23, IL-17, RANKL, RANK, RANKL/OPG, IL-2, IL-6, IL-1β, and TNF-α levels across the three groups were in the order of group P > group E > group N and the OPG levels were in the order of group P < group E < group N (P < 0.05). Emodin may decrease the expression of RANKL and RANK proteins and levels of inflammatory factors; increase OPG, PPAR-γ, and NF-κB protein expression levels; and decrease the number of OCs through the IL-23/Th17 inflammatory axis, thus inhibiting ABL and bone resorption in rats with periodontitis and promoting the proliferation of periodontal ligament cells and alveolar bone repair.

Knockdown of CPT1A Induce Chicken Adipocyte Differentiation to Form Lipid Droplets

Lipid metabolism dysfunction is closely related to obesity, inflammation, diabetes, lipodystrophy, cardiovascular disease. Along with having a positive effect on energy homeostasis during fasting or prolonged exercise through mitochondrial fatty acid oxidation (FAO), more than two dozen enzymes and transport proteins are involved in the activation and transport of fatty acids into the mitochondrial, providing insights into their critical roles in metabolism. CPT1A has been reported to be expressed ubiquitously in the body and associated with dire consequences affecting fat deposition as the key rate-limiting enzyme of FAO. However, there is a dearth of data on the specific role of CPT1A on adipogenic differentiation and adipocyte lipolysis on chicken. This study assessed CPT1A’s function in adipocyte differentiation andadipocyte lipolysis, and the mechanisms were investigated. We found that CPT1A knockdown (KD) promotes the differentiation of chicken preadipocytes into mature adipocytes. CPT1A KD increased PPARγ protein expression level. Expression levels of lipid synthesis-related genes were increased, and lipolysis genes were reduced. Also, CPT1A KD can encourage the formation of lipid droplets. So our results confirmed that knockdown of CPT1A induced the lipid differentiation and inhibited the β-oxidation process to promote the formation of lipid droplets. These findings may deepen our understanding on CPT1A function, especially its regulatory role in adipocyte biology.

Shu-Di-Huang and Gan-Cao Herb Pair Restored the Differentiation Potentials of Mesenchymal Stem Progenitors in Treating Osteoporosis via Downregulation of NF-κB Signaling Pathway.

Background Shu-Di-Huang (Radix Rehmanniae Praeparata, RR) and Gan-Cao (liquorice, L) are frequently used traditional Chinese herb pair in treating osteoporosis (OP). However, the exact mechanism of the RR and L herb pair (RR-L) remains unclear. To explore the efficacy and possible mechanisms of RR-L in treating OP, in silico, in vitro, and in vivo experiments were conducted in the current study. Methods In silico, potential therapeutic target genes and active chemical compounds of RR-L herb pair were predicted and constructed into a network. In vivo, 30 Sprague Dawley rats were divided into 3 groups, including the sham group, the OP model group, and the RR-L-treated OP group. Micro-CT and pathological sections were conducted to validate the therapeutic effects of RR-L in treating OP. MSCs of rats were isolated and cultured in vitro to validate the mesenchymal stem cells (MSCs) related phenotype changes, including Alizarin red staining, Oil red staining, and immunofluorescence. In vitro, cell proliferation analysis, Alizarin red staining, Oil red staining, immunofluorescence of NF-κB, and protein expression of PPARγ, RUNX2, OCN, and p65 were conducted on MSCs to explore the RR-L containing serum in vitro. Also, activator and inhibitor of NF-κB signaling pathway were introduced to determine the possible mechanism of RR-L in the treatment of OP via enhancing MSCs proliferation and differentiation. Results In silico, 168 chemical compounds with a property of oral bioavailability ≥30% and drug-likeness ≥0.18 were recognized as potentially active compounds in RR-L and 249 genes were found to be the targets of which. Among them, 120 genes were found to be therapeutic genes of RR-L in treating OP and KEGG and GO analysis of which demonstrated that RR-L involves in lipid metabolism and multiple inflammation-related signaling pathways. In vivo, ovariectomy- (OVX-) induced OP phenotypes in Sprague Dawley rats include bone mineral density and microarchitecture damaging, abnormal bone metabolism, upregulation of inflammation markers, and damaged differentiation potential of MSCs. Treatment of RR-L reversed the trend and restored the differentiation potential of MSCs. In vitro, RR-L containing serum promoted the osteogenic differentiation and suppressed adipogenic differentiation of MSCs via downregulation of the NF-κB signaling pathway. Also, RR-L containing serum inhibited the tumor necrosis factor-α (TNF-α) induced activation of the NF-κB signaling pathway. On the opposite, the addition of the NF-κB specific inhibitor significantly reduced the effect of RR-L on MSCs. Conclusions In the current study, network pharmacology prediction and experimental validation elucidated that the RR-L herb pair restored damaged MSC differentiation potential via the NF-κB signaling pathway; this could be the possible mechanism of RR-L in treating OP. This finding provides an alternative option in OP therapy.

Hypoglycemic and Hypolipidemic Effects of Malonyl Ginsenosides from American Ginseng (Panax quinquefolius L.) on Type 2 Diabetic Mice

American ginseng (Panax quinquefolius L.) is popularly consumed as traditional herbal medicine and health food for the treatment of type 2 diabetes mellitus (T2DM). Malonyl ginsenosides (MGR) are the main natural ginsenosides in American ginseng. However, whether the malonyl ginsenosides in P. quinquefolius (PQ-MGR) possess antidiabetic effects has not been explored yet. In this study, the antidiabetic effects and the underlying mechanism of PQ-MGR in high-fat diet/streptozotocin (HFD/STZ)-induced T2DM mice were investigated. The chemical composition was analyzed by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). Our results showed that 14 malonyl ginsenosides were identified in the PQ-MGR. Among them, the content of m-Rb1 represented about 77.4% of the total malonyl ginsenosides. After a 5-week experiment, the PQ-MGR significantly reduced the fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), nonesterified fatty acid (NEFA), alanine transaminase (ALT), and aspartate transaminase (AST) levels and improved glucose tolerance and insulin resistance. Furthermore, Western blot analysis demonstrated that the protein expressions of p-PI3K, p-AKT, p-AMPK, p-ACC, PPARγ, and GLUT4 in the liver and skeletal muscle were significantly upregulated after PQ-MGR treatment. In contrast, the protein expressions of p-IRS1 and p-JNK were significantly downregulated. Our results revealed that PQ-MGR could ameliorate glucose and lipid metabolism and insulin resistance in T2DM via regulation of the insulin receptor substrate-1/phosphoinositide3-kinase/protein-kinase B (IRS1/PI3K/Akt) and AMP-activated protein kinase/acetyl-CoA carboxylase (AMPK/ACC) pathways. These findings suggest that PQ-MGR may be used as an antidiabetic candidate drug for T2DM treatment.

Inhibition of PPARγ Gene Particle Downregulates the Differentiation of Rabbit Bone Marrow Mesenchymal Stem Cells into Adipocytes

This study aims to evaluate the effect of peroxisome proliferator-activated receptor (PPAR) γ gene inhibition on the adipogenic differentiation of rabbit bone marrow mesenchymal stem cells (BMSCs). Primary BMSCs were isolated from rabbit bone marrow, cultured, and the markers of BMSCs on cell’s surface were analyzed using flow cytometry. The experiment involved five groups, namely, control: untreated BMSCs; model: BMSCs treated with ethanol; empty siRNA: BMSCs treated with ethanol + empty siRNA; PPARγ: BMSCs treated with ethanol + PPARγ siRNA; and PPARγ inhibitor: BMSCs treated with ethanol + T0070907. RT-PCR and Western blotting were used to detect changes in the expression level of PPARγ, PETALA2 (AP2), lipoprotein lipase (LPL), fatty acid transport protein (FATP) 1, and fatty acid transporter (FAT). Adipocyte count and triacylglycerol content of the model and the empty siRNA groups were considerably greater than the control group ( P &lt; 0.01 ). After the inhibition with PPARγ or T0070907, adipocyte count and triacylglycerol content of the PPARγ and T0070907 groups were significantly reduced ( P &lt; 0.01 ), with no statistically significantly difference than the control group ( P &gt; 0.05 ). The expression levels of PPARγ gene and protein in the model and empty siRNA groups were ominously enhanced than the control group ( P &lt; 0.01 ), and after inhibition with PPARγ or T0070907, the PPARγ gene or protein expression level of PPARγ and T0070907 groups significantly reduced ( P &lt; 0.01 ), with no statistically significance difference compared to the control group ( P &gt; 0.05 ). The expression levels of Ap2, LPL, FATP1, and FAT genes in the model and empty siRNA groups were considerably greater compared to the control group ( P &lt; 0.01 ). Inhibition with PPARγ or T0070907 in the PPARγ and T0070907 groups, respectively, lead to significantly reduced expression levels of adipogenic genes ( P &lt; 0.01 ), with no statistically significance difference compared to the control ( P &gt; 0.05 ). Inhibition of PPARγ gene downregulates the differentiation of BMSCs into adipocytes, indicating its putative role in the expression of adipogenic genes.

Attenuation of Cardiomyopathy Induced in Sub-Chronic Exposure of Acrolein by Sulforaphane via Indirect PPARy Expression Promoter

Abstract: Sulforaphane (SPN) is reported to activate the Nrf2/Keap1 complex responsible for protein and gene expression promotion of various antioxidant enzymes. The present study examined the role of Nrf2 in modulating other signaling pathways involved in SPN’s attenuation of acrolein (ACL)-induced cardiomyopathy in rats. Forty-two rat was categorized into seven 4-week treatment groups: control, SPN, losartan (LTN), ACL, ACL+SPN, ACL+LTN, and ACL+SPN+LTN. Heart samples were harvested for analysis; cardiac oxidative and injury biomarker levels and histopathological examination were undertaken. PPARγ, Nrf2, NF-κB, COX-2, and CYP2E1 protein expressions were examined. Results show that SPN and SPN+LTN reduced GSH, catalase, and lipid peroxidation compared to the ACL-treated group. Also, levels of creatine kinase-MB, cardiac troponin, and caspase 3 induced by ACL were all attenuated. Altered cardiac tissue pathophysiology by ACL was alleviated. SPN+LTN significantly increased Nrf2 expression via PPARγ action but decreased NF-κB and COX-2 expressions. Also, ACLincreased CYP2E1 expression was significantly attenuated by the SPN+LTN combination. For the first time, it suggests that SPN+LTN might offer a better therapeutic alternative to ACL-induced cardiomyopathy by activating Nrf2 via PPARγ and reducing NF-κB/COX- 2/CYP2E1 expressions. Key words: Sulforaphane, Losartan, Acrolein, Cardiomyopathy, Oxidative Stress, PPARγ; Nrf2.

Effect of Metformin and Simvastatin in Inhibiting Proadipogenic Transcription Factors.

Obesity is a multifactorial chronic disease characterized by the excessive accumulation of fat in adipose tissue driven by hypertrophy and hyperplasia of adipocytes through adipogenesis. Adipogenesis plays a key role in the development of obesity and related metabolic disorders, which makes it potential target for the therapeutic approach to obesity. An increasing number of studies confirm the pleiotropic action of the combined treatment with metformin and statins, suggesting their anti-hypertensive, anti-inflammatory, and anti-adipogenic effect. The aim of this study was to analyze the effect of different doses of metformin (MET) and simvastatin (SIM) on the expression of key transcription factors of adipogenesis. Mouse 3T3-L1 preadipocytes were induced to differentiation in adipogenic medium with sustained MET and SIM treatment to assess the effect on adipogenesis. Nine days after initiating adipogenesis, the cells were prepared for further experiments, including Oil Red O staining, RT-PCR, Western blotting, and immunocytochemistry. Treating the cells with the combination of MET and SIM slightly reduced the intensity of Oil Red O staining compared with the control group, and down-regulated mRNA and protein expression of PPARγ, C/EBPα, and SREBP-1C. In conclusion, the inhibitory effect of MET and SIM on adipocyte differentiation, as indicated by decreased lipid accumulation, appears to be mediated through the down-regulation of adipogenic transcription factors, peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding pro-tein α (C/EBPα), and sterol regulatory element-binding protein 1 (SREBP-1C).

Preventive Effect and Molecular Mechanism of Lactobacillus rhamnosus JL1 on Food-Borne Obesity in Mice.

Probiotics can prevent obesity and related metabolic complications. In our study, the protective effect and molecular mechanism of Lactobacillus rhamnosus JL1 (separated from the feces of healthy infants) on high-fat diet mice were investigated. After 10 weeks of dietary intervention with L. rhamnosus JL1 intervention, the body weight of the JL1 group (23.78 g) was significantly lower than that of the HFD group (26.59 g, p < 0.05) and the liver index was reduced. Serum biochemical analysis showed that the TC, TG and LDL-C contents of JL1 group mice were significantly decreased (p < 0.05). Histological images of the mice livers showed that the degree of lipid action and damage of hepatic cells were improved. L. rhamnosus JL1 activated the AMPK pathway, and reduced the gene expression of PPAR-γ, LXR-α and SREBP-1C. In addition, the protein expression of PPAR-γ and LXR-α were reduced. After dietary intervention with L. rhamnosus JL1, the concentration of acetic acid, propionic acid, and butyric acid were increased significantly, especially the concentration of butyric acid, which was 63.16% higher than that of the HFD group (p < 0.05). In conclusion, this study provided a theoretical reference for the development and application of probiotics derived from healthy infant feces in health products and functional foods.

SIRT3 and Metabolic Reprogramming Mediate the Antiproliferative Effects of Whey in Human Colon Cancer Cells.

Simple SummaryColorectal cancer (CRC) is the second leading cause of cancer-related deaths and the most frequently diagnosed cancer type. CRC risk can be preventable by modifiable risk factors, including diet. This study provides evidence on the antiproliferative and pro-apoptotic effects of whey from Mediterranean water buffalo (Bubalus bubalis) milk in HT-29, HCT 116, LoVo, and SW480 cells. Results showed that whey induced metabolic dysfunctions and modulated the bioenergetic signature of CRC cells by targeting SIRT3 expression. These findings unveil the anti-neoplastic effects of whey and pave the way for the use of this by-product, rich in bioactive nutrients, in the setting of novel prevention strategies to reduce the risk of CRC.Emerging strategies to improve healthy aging include dietary interventions as a tool to promote health benefits and reduce the incidence of aging-related comorbidities. The health benefits of milk are also linked to its richness in betaines and short-chain acylcarnitines, which act synergistically in conferring anticancer, anti-inflammatory, and antioxidant properties. Whey, despite being a dairy by-product, still has a considerable content of bioactive betaines and acylcarnitines. Here, we investigated the anticancer properties of whey from Mediterranean water buffalo (Bubalus bubalis) milk by testing its antiproliferative effects in colorectal cancer (CRC) cells HT-29, HCT 116, LoVo and SW480. Results indicated that treatment with whey for 72 h inhibited cell proliferation (p < 0.001), induced cell cycle arrest, and apoptosis via caspase-3 activation, and modulated cell metabolism by limiting glucose uptake and interfering with mitochondrial energy metabolism with the highest effects observed in HT-29 and HCT 116 cells. At molecular level, these effects were accompanied by upregulation of sirtuin 3 (SIRT3) (p < 0.01) and peroxisome proliferator-activated receptor (PPAR)-γ expression (p < 0.001), and downregulation of lactate dehydrogenase A (LDHA) (p < 0.01), sterol regulatory-element binding protein 1 (SREBP1) (p < 0.05), and PPAR-α (p < 0.01). Transient SIRT3 gene silencing blocked the effects of whey on the LDHA, PPAR-γ, and PPAR-α protein expressions (p < 0.01) suggesting that the whey capacity of perturbating the metabolic homeostasis in CRC cell lines is mediated by SIRT3.

Lobeglitazone, A Peroxisome Proliferator-Activated Receptor-Gamma Agonist, Inhibits Papillary Thyroid Cancer Cell Migration and Invasion by Suppressing p38 MAPK Signaling Pathway.

BackgroundPeroxisome proliferator-activated receptor-gamma (PPAR-γ) ligands have been widely shown to correlate with epithelial-mesenchymal transition (EMT) and cancer progression. Lobeglitazone (LGZ) is a novel ligand of PPAR-γ; and its role in EMT and metastasis in papillary thyroid carcinoma (PTC) is poorly understood. We aimed to investigate the role of LGZ in metastatic behavior of PTC cells.MethodsHalf maximal inhibitory concentration (IC50) values of LGZ in BRAF-mutated PTC cell lines (BCPAP and K1) were determined using MTT assay. Rosiglitazone (RGZ), the PPAR-γ ligand was used as a positive control. The protein expression of PPAR-γ, cell-surface proteins (E-cadherin, N-cadherin), cytoskeletal protein (Vimentin), transcription factor (Snail), p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) 1/2 pathway, and matrix metalloproteinase (MMP)-2 expression were measured using Western blotting. Changes in E-cadherin expression were also determined using immunocytochemistry. Cell migration and invasion were analyzed using wound healing and Matrigel invasion assays.ResultsTreatment with LGZ or RGZ significantly inhibited transforming growth factor-beta1 (TGF-β1)-induced EMT-associated processes such as fibroblast-like morphological changes, EMT-related protein expression, and increased cell migration and invasion in BCPAP and K1 cells. LGZ restored TGF-β1-induced loss of E-cadherin, as observed using immunocytochemistry. Furthermore, LGZ and RGZ suppressed TGF-β1-induced MMP-2 expression and phosphorylation of p38 MAPK, but not ERK1/2. Although there was no change in PPAR-γ expression after treatment with LGZ or RGZ, the effect of downstream processes mediated by LGZ was hampered by GW9662, a PPAR-γ antagonist.ConclusionLGZ inhibits TGF-β1-induced EMT, migration, and invasion through the p38 MAPK signaling pathway in a PPAR-γ-dependent manner in PTC cells.

Bioactive Fraction of Aronia melanocarpa Fruit Inhibits Adipogenic Differentiation of Cultured 3T3-L1 Cells

Obesity is caused by excessive fat cells and the overgrowth of adipocytes and is a major risk factor for several chronic illnesses. Aronia melanocarpa fruit is rich in anthocyanins and polyphenols and has protective effects against various diseases. In this study, we examined the effect of Aronia extract (Aronia bioactive fraction, ABF®) on the biomarkers of the adipogenic pathway during adipocyte differentiation of 3T3-L1 cells. Lipid accumulation was verified by Oil Red O staining. mRNA and protein expression of lipoprotein lipase (LPL), CCAAT/enhancer-binding protein α (C/EBPα), peroxisome proliferator-activated receptor γ (PPARγ), fatty acid-binding protein 2 (FABP2), and fatty acid synthase (FAS) were assayed by RT-qPCR and Western blot analyses. Adiponectin and leptin secretion were measured using enzyme-linked immunosorbent assays. ABF® treatment downregulated lipid accumulation based on Oil Red O staining. ABF®-treated cells exhibited decreased mRNA and protein expression of LPL, C/EBPα, PPARγ, FABP2, and FAS. Moreover, ABF® treatment significantly increased adiponectin secretion and decreased leptin secretion. In conclusion, ABF® has anti-adipogenic effects on the differentiation of 3T3-L1 cells and may be used as an anti-obesity nutraceutical.

Berberine exerts neuroprotective activities against cerebral ischemia/reperfusion injury through up-regulating PPAR-γ to suppress NF-κB-mediated pyroptosis

ObjectiveBerberine (BBR) is an anti-inflammatory alkaloid compound extracted from herbs. The purpose of this study is to probe the possible effect and the mechanism of BBR against cerebral ischemia/reperfusion (I/R) injury. MethodsIn vitro oxygen and glucose deprivation (OGD) model was established on neurons from rat hippocampus, which was then subjected to BBR, IVA337 (PPAR-γ agonist), or GW9662 (PPAR-γ antagonist) treatment, to identify their effects on neuronal pyroptosis. MTT assay was utilized to determine cell survival rates, TUNEL staining for observation of β-tubulin and MAP2 expressions, qRT-PCR for detection of mRNA expression of PPAR-γ, Western blot for assessment of protein expressions of PPAR-γ and pyroptosis-related proteins (AIM2, NLPR3, ASC, cleaved-Caspase-1, GSDMD, and GSDMD-N), and ELISA for examination of IL-18 and IL-1β expressions. ResultsOGD modeling induced neuron pyroptosis, as evidenced by increased expression levels of pyroptosis-related proteins as well as IL-1β and IL-18, and elevated cell apoptosis rate. In addition, OGD exposure led to PPAR-γ up-regulation and NF-κB activation. Overexpression of PPAR-γ ameliorated cell pyroptosis, while knockdown of PPAR-γ intensified neuron pyroptosis that could be reversed by BBR. Furthermore, either BBR could block the activation of NF-κB signaling pathway through PPAR-γ. ConclusionBBR protects rats from cerebral I/R injury by up-regulating PPAR-γ to restrain NF-κB-mediated pyroptosis.

MiRNA-130a promotes inflammation to accelerate atherosclerosis via the regulation of proliferator-activated receptor γ (PPARγ) expression

In this study, we aimed to evaluate the possible function of miR-130a in atherosclerosis (AS), protection against AS, and its molecular biological mechanism. Apoe-/- mice were fed a high-fat diet as the AS mice model. Human umbilical vein endothelial cells (HUVECs) were used as in vitro model. Serum samples or cells were used to measure the expression of inflammation. Serum samples or cells were used to determine MiRNA expression profiles using the edgeR tool from Bioconductor. Western Blot analysis was used to assess protein expressions of proliferator-activated receptor γ (PPARγ) and nuclear factor (NF)-κB. MiRNA-130a expression was up-regulated in atherosclerotic mice. In addition, over-expression of miRNA-130a promoted inflammation factors [tumor necrosis factor (TNF)-α and interleukin (IL)-1β, IL-6, and IL-8] in the in vitro model of AS. However, down-regulation of miRNA-130a reduced inflammation (suppressed TNF-α, IL-1β, IL-6 and IL-8) in the in vitro model. Furthermore, over-expression of miRNA-130a could also suppress the protein expression of PPARγ and induce NF-κB protein expression in the in vitro model. However, suppression of miRNA-130a induced the protein expression of PPARγ and suppressed NF-κB protein expression in the in vitro model of AS. Activation of PPARγ reduced the pro-inflammatory effects of miRNA-130a on the AS-induced in vitro model. These results strongly support that miRNA-130a suppression can protect against atherosclerosis through inhibiting inflammation by regulating the PPARγ/ NF-κB expression.

Decabromodiphenyl ether causes insulin resistance and glucose and lipid metabolism disorders in mice.

BACKGROUNDDecabromodiphenyl ether (BDE-209) is the most commonly used brominated flame retardant. Recently, BDE-209 has been suspected of being an environmental risk factor for metabolic diseases such as obesity, insulin resistance (IR), type 2 diabetes mellitus, and hypertension.AIMTo investigate the effects of BDE-209 on IR and glucose and lipid metabolism in C57BL/6 mice.METHODSAdult male C57BL/6 mice were randomly divided into high, medium-high, medium, medium-low, and low dose BDE-209 groups, and a control group (n = 6 per group), which received 1000, 800, 600, 450, 300, and 0 mg/kg BDE-209, respectively. After BDE-209 exposure for 60 d, the mice were fasted overnight, and then sacrificed to obtain tissues. An automatic biochemical analyzer was used to detect serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C); enzyme-linked immunosorbent assay kits were used to detect fasting serum insulin (FINS), leptin (LEP), and adiponectin (Adp) levels; a blood glucose meter was used to detect fasting blood glucose (FBG). Morphological changes of the liver were observed by hematoxylin and eosin staining. Real-time quantitative polymerase chain reaction and Western blot were used to determine the messenger ribonucleic acid (mRNA) and protein levels, respectively, of LEP, Adp, and peroxisome proliferators activated receptor-γ (PPARγ) in mouse liver and adipose tissues.RESULTSThere was a statistically significant difference in the weight of mice in each group after 45 and 60 d of exposure (P < 0.05). After 60 d of exposure, the weight of liver and adipose tissues in the exposure groups were greater than that of the control group (P < 0.05). The liver tissue structure was disordered and the liver tissues were accompanied by local inflammatory cell infiltration in the high, medium-high, and medium dose BDE-209 groups. The levels of FINS, insulin sensitivity index, Adp, and HDL-C were decreased in the BDE-209 group compared with the control group, as were the mRNA and protein levels of Adp in liver and adipose tissues (P < 0.05). Serum level of FBG and LEP were higher in the BDE-209 group than in controls. TC, TG, and LDL-C levels as well as the mRNA and protein expression of LEP and PPARγ in liver and adipose tissues were higher than those in the control group (P < 0.05). Homeostatic assessment model of IR was higher in the medium and medium-low dose BDE-209 groups (P < 0.05). CONCLUSIONBDE-209 increases the body weight, fat and liver tissue weight, TC, TG, and LDL-C, reduces HDL-C, and causes IR in mice, which may be related to activating the PPARγ receptor.

Flavonoids from Hypericum patulum enhance glucose consumption and attenuate lipid accumulation in HepG2 cells.

Hypericum patulum has been used as a folk medicine for its varied therapeutic effects including antifungal, wound-healing, spasmolytic, stimulant, hypotensive activities. The water decoction is drank as tea could treat cold, infantile malnutrition. The present study aims to isolate the constituents of the plant and investigate their effects on the glucose consumption in insulin-resistant HepG2 cells,furthermore, lipid metabolism in oleic acid (OA)-treated HepG2 cells was also studied. The phytochemical investigation of the plant led to the isolation of eleven compounds, and their structures were identified by spectroscopic analysis as n-dotriacontanol (1), shikimic acid (2), 1-O-caffeoylquinic acid methyl ester (3), 5-O-caffeoylquinic acid methyl ester (4), 5-O-coumaroylquinic acid methyl ester (5), 5-O-caffeoylquinic acid butyl ester (6), quercetin-3-O-α-L-rhamnoside (7), quercetin (8), quercetin-3-O-(4״-methoxy)-α-L-rahmnopyranosyl (9), hyperoside (10), and rutin (11). The results revealed that compounds 7, 9, and 10 could enhance glucose consumption significantly in hyperglycemia induced HepG2 cells and insulin-resistant HepG2 cells. In addition, the western blotting analysis result exhibited that compounds 7, 9, and 10 in high concentration (5μM, H) group could dramatically upregulate the expression of PPARγ protein, and even the effect of them had no significant difference compared with that of rosiglitazone. Furthermore, compounds 9 and 10 in middle concentration (2.5μM, M) group and H group could dramatically promote triglyceride metabolism and decrease TG content in OA-treated HepG2 cells, and even in H group, reactive oxygen species (ROS) level were significantly decreased compared with model group. PRACTICAL APPLICATIONS: Hypericum patulum is a well-known plant of the genera Hypericum for its varied preventive and therapeutic potential activities. To study the chemical constituents and their effects on glucose and lipid metabolism in vitro, we detected glucose consumption in insulin-resistant HepG2 cells, triglyceride content and reactive oxygen species level in OA-treated HepG2 cells. In addition, PPARγ protein was also detected by western blotting analysis in the study. Compounds 1, 2, 3, 5, 6, 9, 10, and 11 were isolated from the plant for the first time. Quercetin-3-O-(4"-methoxy)-α-L-rahmnopyranosyl (9) and hyperoside (10) had potential therapeutic benefit against glucose and lipid metabolic disease. Therefore, this study might have certain guiding significance for further research and development of H. patulum.

Synergistic effect of combined treatment with baicalin and emodin on DSS-induced colitis in mouse.

The treatment of combination drugs in complex diseases has been spotlighted. Ulcerative colitis (UC) is a chronic inflammatory disease that has made progress in combination therapy. Baicalin, a flavone from Scutellaria baicalensis Georgi. (Lamiaceae), and emodin, an anthraquinone derivative from Rhei Radix et Rhizoma. (Polygonaceae), both have been reported to possess antiinflammatory activities. Our study investigated whether combined treatment with baicalin and emodin had a synergistic effect in inhibiting colitis inflammation. The results showed that baicalin combined with emodin at a lower dose had the same effect as the two drugs alone significantly alleviated the symptoms of dextran sulfate sodium (DSS)-induced colitis mice, involving the prevention of the loss of body weight and colon shortening, the decrease in the disease activity index (DAI), and intestinal damages. The combined treatment decreased the expression of CD14/TLR4/NF-κB pathway proteins and increased the expression of PPAR-γ protein in the colon of colitis mice. Further study in vitro has shown that baicalin decreased the expression of CD14, whereas emodin increased the expression of PPAR-γ, both of which inhibited the activity of NF-κB and exerted antiinflammatory effects. Furthermore, compared to the treatment using the two drugs individually, baicalin combined with emodin had more significant effects on the expression of CD14 and PPAR-γ. Therefore, emodin combined with baicalin had a synergistic effect on DSS-induced colitis.

PPARγ as an indicator of vascular function in an experimental model of metabolic syndrome in rabbits

Background and aimsUnderlying mechanisms associated with vascular dysfunction in metabolic syndrome (MetS) remain unclear and can even vary from one vascular bed to another. MethodsIn this study, MetS was induced by a high-fat, high-sucrose diet, and after 28 weeks, aorta and renal arteries were removed and used for isometric recording of tension in organ baths, protein expression by Western blot, and histological analysis to assess the presence of atherosclerosis. ResultsMetS induced a mild hypertension, pre-diabetes, central obesity and dyslipidaemia. Our results indicated that MetS did not change the contractile response in either the aorta or renal artery. Conversely, vasodilation was affected in both arteries in a different way. The aorta from MetS showed vascular dysfunction, including lower response to acetylcholine and sodium nitroprusside, while the renal artery from MetS presented a preserved relaxation to acetylcholine and an increased sensitivity to sodium nitroprusside. We did not find vascular oxidative stress in the aorta from MetS, but we found a significant decrease in PPARγ, phospho-Akt (p-Akt) and phospho-eNOS (p-eNOS) protein expression. On the other hand, we found oxidative stress in the renal artery from MetS, and PPARγ, Akt and p-Akt were overexpressed. No evidence of atherosclerosis was found in arteries from MetS. ConclusionsMetS affects vascular function differently depending on the vessel. In the aorta, it decreases both the vasodilation and the expression of the PPARγ/Akt/eNOS pathway, while in the renal artery, it increases the expression of PPARγ/Akt signalling pathway without decreasing the vasodilation.

Magnolia officinalis Ameliorates Dehydroepiandrosterone-Induced Polycystic Ovary Syndrome in Rats

Background: Polycystic ovary syndrome (PCOS) is a prevalent reproductive and metabolic disorder. Insulin resistance (IR) is highly associated with PCOS and aggravates its symptoms. Thiazolidinediones (TZDs), as insulin sensitizing agents, are PPARγ agonists that improve many of the symptoms of PCOS. The Magnolia officinalis extract (MOE) is a natural peroxisome proliferator activated receptor gamma (PPARγ) agonist that improves insulin sensitivity in experimental models. Objectives: Using a dehydroepiandrosterone (DHEA)-induced rat model of PCOS and IR, this study aimed to explore both the potential beneficial effects and the molecular mechanisms of action of MOE. Methods: Post-pubertal female Sprague Dawley rats were subcutaneously injected daily with DHEA (6 mg/100 g body weight) dissolved in sesame oil for 28 days (n = 30). Age- and weight-matched control rats received only sesame oil (n = 12). Afterward, 16 of the DHEA-injected rats, along with five control rats, were sacrificed for blood and tissue collection. The 14 remaining DHEA-injected rats received either treatment of 30 days of oral MOE (500 mg/kg) dissolved in dimethyl sulfoxide (DMSO) (n = 7), or oral DMSO only (n = 7). Meanwhile, the remaining control rats (n = 7) continued to receive daily oral DMSO for 30 days. At the end of the treatments, the rats were sacrificed for blood and tissue collection. Results: After 28 days, the DHEA-treated rats exhibited an increase in body weight as compared to controls (P &lt; 0.05). DHEA injection induced a PCOS phenotype as evident by a statistically significant (P &lt; 0.05) elevated serum luteinizing hormone (LH), and an increased number of cystically dilated follicles with thicker granulosa compared to controls. PCOS rats showed a statistically significant rise in fasting insulin with an increased homeostatic model assessment index of insulin resistance (HOMA-IR) as compared to controls (P &lt; 0.05). Compared to the control group, PCOS rats had a statistically significant lower ovarian protein expression of PPARγ, insulin receptor substrate 1 (IRS1), and protein kinase B (Akt) by Western Blot (P &lt; 0.05). Conversely, the PCOS group showed an increased mammalian target of rapamycin (mTOR) pathway activity as evident by an increase in the fraction of phosphorylated mTOR to total mTOR compared to the control group (P &lt; 0.05). When treated for 30 days with oral MOE (500 mg/kg), the PCOS rats showed a statistically significant decrease in body weight and serum LH levels as compared to the non-treated PCOS rats (P &lt; 0.05). The number of cystically dilated follicles in the MOE-treated PCOS rats was significantly reduced compared to the non-treated PCOS rats. In the MOE-treated PCOS rats, the ovarian protein expression of PPARγ, IRS1, and Akt was significantly increased, while the p-mTOR/mTOR expression was decreased compared to the non-treated PCOS group (P &lt; 0.05). Conclusions: According to our results, the MOE ameliorated the DHEA-induced PCOS phenotype histologically, hormonally, and metabolically. Fundamentally, this explores the elusive pathophysiologic association between IR and PCOS by targeting pathways common to both disorders.

Post-Treatment with Amorfrutin B Evokes PPARγ-Mediated Neuroprotection against Hypoxia and Ischemia

In this study, we demonstrate for the first time that amorfrutin B, a selective modulator of peroxisome proliferator-activated receptor gamma—PPARγ, can protect brain neurons from hypoxia- and ischemia-induced degeneration when applied at 6 h post-treatment in primary cultures. The neuroprotective effect of amorfrutin B suggests that it promotes mitochondrial integrity and is capable of inhibiting reactive oxygen species—ROS activity and ROS-mediated DNA damage. PPARγ antagonist and Pparg mRNA silencing abolished the neuroprotective effect of amorfrutin B, which points to agonistic action of the compound on the respective receptor. Interestingly, amorfrutin B stimulated the methylation of the Pparg gene, both during hypoxia and ischemia. Amorfrutin B also increased the protein level of PPARγ during hypoxia but decreased the mRNA and protein levels of PPARγ during ischemia. Under ischemic conditions, amorfrutin B-evoked hypermethylation of the Pparg gene is in line with the decrease in the mRNA and protein expression of PPARγ. However, under hypoxic conditions, amorfrutin B-dependent hypermethylation of the Pparg gene does not explain the amorfrutin B-dependent increase in receptor protein expression, which suggests other regulatory mechanisms. Other epigenetic parameters, such as HAT and/or sirtuins activities, were affected by amorfrutin B under hypoxic and ischemic conditions. These properties position the compound among the most promising anti-stroke and wide-window therapeutics.

Pioglitazone Ameliorates Renal Ischemia-Reperfusion Injury via Inhibition of NF-κB Activation and Inflammation in Rats

Renal ischemia-reperfusion injury (IRI) is considered as a major cause of acute kidney injury. In this study, we investigated the role of the NF-κB signaling pathway and inflammation in the amelioration of renal IRI using pioglitazone. Sprague–Dawley (SD) rats were subjected to bilateral renal artery clamping for 45 min followed by perfusion restoration for establishing a simulated renal IRI model. At 24 h post-operatively, we assessed the serum levels of creatinine and urea nitrogen, expression levels of peroxisome proliferator-activated receptor gamma (PPAR-γ) and NF-κB-related (p-IKK-β and IκB-α) proteins, and mRNA expression levels of the inflammatory cytokines, including TNF-α and MCP-1, in the renal tissue of various study groups. The histopathological evaluation of renal tissue was also conducted. In rat renal tissue, pioglitazone treatment decreased the serum levels of post-renal IRI creatinine and urea nitrogen, as well as necrosis. Furthermore, it elevated the expression of PPAR-γ protein and decreased the expression of NF-κB-related proteins. Pioglitazone also decreased the mRNA expression of TNF-α and MCP-1 in the renal tissue. Thus, pioglitazone ameliorates renal IRI by inhibiting the NF-κB signaling pathway and inflammatory response in rats.