Peroxisome Proliferator-activated Receptor Gamma Signaling Research Articles

Computational investigation of Pluchea indica mechanism targeting peroxisome proliferator-activated receptor gamma

Introduction: Pluchea indica is known to have diverse pharmacological properties, including anti-inflammatory, antioxidant, antimicrobial, and anticancer activities. However, there is a pressing need to thoroughly investigate the molecular interactions between P. indica compounds and peroxisome proliferator-activated receptor gamma (PPARG). This study aimed to elucidate the molecular mechanisms behind P. indica and PPARG, and its potential implications for diabetes mellitus. Methods: The computational investigation employed Pharmacological Network pharmacology, homology modeling, deep learning docking, and molecular dynamics to explore the active compounds and targets within P. indica against the PPARG. Results: Three active compounds were identified namely pinoresinol, syringaresinol, and plucheoside A, all of which complied with the Lipinski rule of five. The deep learning-based pose scores were determined as follows: Pinoresinol 0.55, syringaresinol 0.32, and plucheoside A 0.44. Additionally, protein-protein interactions were observed with PPARG and associated with the PPAR signaling pathway. Molecular dynamics simulation analysis showed the stability of the three compounds over a 100 ns period. Free energy calculations using Molecular Mechanics-Generalized Born and Surface Area (MM-GBSA) yielded ΔG values of -44.39 kcal/mol, -51.83 kcal/mol, and -40.27 kcal/mol for pinoresinol, syringaresinol, and plucheoside A, respectively. Conclusion: Pluchea indica might be developed to treat various diseases, particularly those involving the PPARG signaling pathway. It suggests the possibility of being developed as a focused medication for diabetes.

Er-Dong-Xiao-Ke decoction regulates lipid metabolism via PPARG-mediated UCP2/AMPK signaling to alleviate diabetic meibomian gland dysfunction

Ethnopharmacological relevanceMeibomian gland dysfunction (MGD), complicated by type 2 diabetes, is associated with a high incidence of ocular surface disease, and no effective drug treatment exists. Diabetes mellitus (DM) MGD shows a notable disturbance in lipid metabolism. Er-Dong-Xiao-Ke decoction (EDXKD) has important functions in nourishing yin, clearing heat, and removing blood stasis, which are effective in the treatment of DM MGD. Aim of the studyTo observe the therapeutic effect of EDXKD on DM MGD and its underlying molecular mechanism. Materials and methodsAfter establishing a type 2 DM (T2DM)-induced MGD rat model, different doses of EDXKD and T0070907 were administered. The chemical constituents of EDXKD were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the molecular mechanism of EDXKD in treating DM MGD was predicted using network pharmacology. Lipid metabolism in DM meibomian glands (MGs) was analyzed using LC-MS/MS, and lipid biomarkers were screened and identified. Histological changes and lipid accumulation in MGs were detected by staining, and Peroxisome proliferator-activated receptor gamma (PPARG) expression in MG acinar cells was detected by immunofluorescence. The expression of lipid metabolism-related factors was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) or western blotting. ResultsEDXKD reduced lipid accumulation in the MGs and improved the ocular surface index in DM MGD rats. The main active components of EDXKD had advantages in lipid regulation. Additionally, the PPARG signaling pathway was the key pathway of EDXKD in the treatment of DM MGD. Twelve lipid metabolites were biomarkers of EDXKD in the treatment of DM MGD, and glycerophospholipid metabolism was the main pathway of lipid regulation. Moreover, EDXKD improved lipid deposition in the acini and upregulated the expression of PPARG. Further, EDXKD regulated the PPARG-mediated UCP2/AMPK signaling network, inhibited lipid production, and promoted lipid transport. ConclusionEDXKD is an effective treatment for MGD in patients with T2DM. EDXKD can regulate lipids by regulating the PPARG-mediated UCP2/AMPK signaling network, as it reduced lipid accumulation in the MGs of DM MGD rats, promoted lipid metabolism, and improved MG function and ocular surface indices.

Krüppel-like factor 15 deficiency exacerbates osteoarthritis through reduced expression of peroxisome proliferator-activated receptor gamma signaling in mice

Krüppel-like zinc finger transcription factors (KLFs) play diverse roles in mammalian cell differentiation and development. In this study, we investigated the function of KLF15 in the progression of osteoarthritis (OA). 0Destabilization of the medial meniscus (DMM) surgery was performed in 10-week-old male wild-type control (WT) mice and cartilage-specific KLF15 knockout (KO) mice. Histological analysis, immunohistochemistry, and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling staining were performed. Morphological changes were measured using microcomputed tomography. Six mice from each group were analyzed (total number of mice analyzed: 60). In vitro, immunofluorescence, quantitative reverse transcription-polymerase chain reaction, and western blot analyses were performed. KLF15 KO DMM mice exhibited significant cartilage degradation compared to WT mice. According to the Osteoarthritis Research Society International cartilage OA-histopathology scoring system, the mean sum score in KLF15 KO mice was significantly higher than that in WT mice at 8 weeks after surgery. Immunohistochemistry results revealed KLF15 KO mice exhibited reducedperoxisome proliferator-activated receptor gamma (PPARγ) expression, increased pIKKα/β, a disintegrin-like and metalloproteinase with thrombospondin motifs (ADAMTS) 5, and Matrix metalloproteinases (MMP13) expression, and reduced Forkhead box O (FOXO1) and Light chain 3B (LC3B) expression. Inhibition of PPARγ phosphorylation accelerated the effects of interleukin (IL) 1β-treatment in both KLF15 KO and WT chondrocytes, and activation of PPARγ expression canceled the IL1β-induced catabolic effects. Our results indicated that the OA phenotype of KLF15 KO DMM mice was influenced by reduced PPARγ expression, including enhanced pIKKα/β, ADAMTS5, and MMP13 expression, reduced autophagy, and increased apoptosis. KLF15 regulation may constitute a possible therapeutic strategy for the treating OA.

Reno- and hepato-protective effect of allopurinol after renal ischemia/reperfusion injury: Crosstalk between xanthine oxidase and peroxisome proliferator-activated receptor gamma signaling.

Renal ischemia/reperfusion (I/R) is a common cause of acute kidney injury and remote liver damage is an ultimate negative outcome. Current treatments for renal I/R typically involve the use of antioxidants and anti-inflammatory to protect against oxidative stress and inflammation. Xanthine oxidase (XO) and PPAR-γ contribute to renal I/R-induced oxidative stress; however, the crosstalk between the two pathways remains unexplored. In the present study, we report that XO inhibitor, allopurinol (ALP), protects kidney and liver after renal I/R by PPAR-γ activation. Rats with renal I/R showed reduced kidney and liver functions, increased XO, and decreased PPAR-γ. ALP increased PPAR-γ expression and improved liver and kidney functions. ALP also reduced inflammation and nitrosative stress indicated by reduction in TNF-α, iNOS, nitric oxide (NO), and peroxynitrite formation. Interestingly, rats co-treated with PPAR-γ inhibitor, BADGE, and ALP showed diminished beneficial effect on renal and kidney functions, inflammation, and nitrosative stress. This data suggests that downregulation of PPAR-γ contributes to nitrosative stress and inflammation in renal I/R and the use of ALP reverses this effect by increasing PPAR-γ expression. In conclusion, this study highlights the potential therapeutic value of ALP and suggests targeting XO-PPAR-γ pathway as a promising strategy for preventing renal I/R injury.

Abstract ND08: Discovery of FX-909, a first-in-class inverse agonist of the peroxisome proliferator-activated receptor gamma (PPARG) lineage transcription factor, to potentially treat patients with the luminal subtype of advanced urothelial cancer (UC)

Abstract Although the treatment landscape of advanced urothelial cancer (UC) has changed dynamically over the last decade, metastatic UC still has amongst the worst 5-year recurrence rate of any cancer type, highlighting the need for new therapeutic options for these patients. Analogous to breast cancer, advanced UC is a heterogeneous disease, with luminal and basal subtypes. For luminal breast cancer, small molecule targeting of the lineage-defining transcription factor estrogen receptor (ER) is a demonstrated and effective therapeutic strategy. Two-thirds of advanced UC is classified as luminal, which is characterized by overexpression of the urothelial lineage-defining transcription factor PPARG. Thus, small molecule targeting of PPARG in luminal UC may serve as a therapeutic strategy analogous to ER in luminal breast cancer. While PPARG agonists have been well studied in the context of metabolic disease, PPARG inhibitors have received far less attention. Previously reported PPARG inhibitors display minimal phenotypic activity in pre-clinical UC models, calling into question the performance of these molecules, or alternatively, the role of PPARG as a survival lineage oncogene in UC. Leveraging reconstituted, multi-component PPARG biochemical systems, we first identified the limitations of previous tool compounds and then discovered a novel, covalent lead series with unique, context-dependent electrophilic properties. These efforts lead to the discovery of FX-909, a first-in-class covalent PPARG inverse agonist with powerful repressive conformational biasing activity. FX-909 is highly potent in cells (IC50=1 nM), demonstrates high specificity for PPARG (>2000-fold selective over PPARA/PPARD), and elicits robust in vitro growth inhibition in UC cell lines with activated PPARG signaling. Tumor regression was observed in UMUC9 (PPARG amplification) and HT1197 (RXRAS427F hotspot mutation) xenograft models of UC with oral dosing at 1 mg/kg. Predictable, on-target and reversible pharmacology was observed at FX-909 doses above 1 mg/kg, mimicking PPARG loss-of-function mutations with notable tissue remodeling in adipose tissue and the normal urothelium. These collective findings corroborate the role of PPARG as a key UC survival oncogene and suggest that FX-909 will be an effective therapy for patients with advanced UC harboring the luminal subtype. Citation Format: Robert Sims, Jennifer A. Mertz, Jonathan E. Wilson, James E. Audia, Kaylyn E. Williamson, Yong Li, Miljan Kuljanin, Will W. Motely, Byron DeLaBarre, Michaela Bowden, Jacob I. Stuckey. Discovery of FX-909, a first-in-class inverse agonist of the peroxisome proliferator-activated receptor gamma (PPARG) lineage transcription factor, to potentially treat patients with the luminal subtype of advanced urothelial cancer (UC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr ND08.

94 (PB084) - Novel inhibitors of the luminal lineage transcription factor peroxisome proliferator-activated receptor gamma (PPARG) durably eradicate tumors in urothelial cancer (UC) animal models

Background: Small molecule targeting of cell lineage-defining transcription factors is a demonstrated and effective therapeutic strategy in oncology, exemplified by estrogen receptor (ER) agents in luminal breast cancer. Two-thirds of advanced UC is classified as luminal and overexpression of PPARG is characteristic of this molecular subtype. Currently, there is a poor understanding of how recurrent missense mutations in PPARG and its obligate heterodimer retinoid X receptor alpha (RXRA) impact PPARG function; previous tool compounds designed to inhibit PPARG have minimal phenotypic activity in UC cell lines. Material and Methods: The PPARG inhibitor FTX-6746 was evaluated in UC cell lines including UMUC9 (PPARG amplification) and HT1197 (RXRA-S427F hotspot mutation), which activate PPARG by different genetic mechanisms. In vitro analyses included clonogenic growth assays and assessment of target gene modulation after treatment. in vivo studies were performed in NCG or Balb/C nude mice with oral administration of FTX-6746 at doses indicated below. Results: Our biochemical studies indicate that patient-derived missense mutations in PPARG and RXRA bias an active conformation of PPARG, mimicking an agonist-bound state. Addressing the limitations of previous tool compounds, we discovered novel inhibitors that drive a powerful repressive conformation of PPARG with high specificity (>100X selective over PPARA/ PPARD). This results in robust PPARG target gene silencing in cells (IC50 = 5 nM), and in vitro growth inhibition preferentially observed in cell lines with activated PPARG signaling. Tumor growth inhibition or regression was observed in two xenograft models of UC at well-tolerated oral doses with no tumor regrowth upon cessation of treatment. Treatment of UMUC9 xenograft tumors with 3, 10, 30 and 60 mg/kg twice daily of FTX-6746 resulted in up to 80% target gene suppression in tumor tissue at day 2 and up to >100% tumor growth inhibition at day 21. Similar efficacy was observed in HT1197 xenograft studies treated with 30 and 60 mg/kg twice daily of FTX-6746, with >45% target gene suppression at day 2 and 85–112% tumor growth inhibition at day 42.Tabled 1ModelDose (mg/kg)Schedule%Tumor Growth Inhibition%Target Gene Suppression (D2)UMUC93BID*205916UMUC910BID*2070NDUMUC930BID*208373UMUC930BID*2110580UMUC960BID*21108NDHT119730BID*428546HT119760BID*4211259 Open table in a new tab Conclusions: These collective results suggest that PPARG is a lineage-defining transcription factor in UC and small molecule PPARG inhibition will be an effective therapy for patients with advanced urothelial cancer harboring the luminal subtype. Conflict of interest: Ownership: All authors are shareholders in Flare Therapeutics.

Effects of dietary n-6:n-3 polyunsaturated fatty acid ratio on growth performance, blood indexes, tissue fatty acid composition and the expression of peroxisome proliferator-activated receptor gamma signaling related genes in finishing pigs.

ObjectiveThis study investigated the effects of dietary n-6:n-3 polyunsaturated fatty acid (PUFA) ratio on growth performance, blood indexes, tissue fatty acid composition and the gene expression in finishing pigs.MethodsSeventy-two crossbred ([Duroc×Landrace]×Yorkshire) barrows (68.5±1.8 kg) were fed one of four isoenergetic and isonitrogenous diets with n-6:n-3 PUFA ratios of 2:1, 3:1, 5:1, and 8:1.ResultsAverage daily gain, average daily feed intake and gain-to-feed ratio had quadratic responses but the measurements were increased and then decreased (quadratic, p<0.05). The concentrations of serum triglyceride, total cholesterol and interleukin 6 were linearly increased (p<0.05) with increasing of dietary n-6:n-3 PUFA ratio, while that of high-density lipoprotein cholesterol tended to decrease (p = 0.062), and high-density lipoprotein cholesterol:low-density lipoprotein cholesterol ratio and leptin concentration were linearly decreased (p<0.05). The concentration of serum adiponectin had a quadratic response but the measurement was decreased and then increased (quadratic, p<0.05). The proportion of C18:3n-3 was linearly decreased (p<0.05) in the longissimus thoracis (LT) and subcutaneous adipose tissue (SCAT) as dietary n-6:n-3 PUFA ratio increasing, while the proportion of C18:2n-6 and n-6:n-3 PUFA ratio were linearly increased (p<0.05). In addition, the expression levels of peroxisome proliferator-activated receptor gamma (PPARγ) and lipoprotein lipase in the LT and SCAT, and adipocyte fatty acid binding protein and hormone-sensitive lipase (HSL) in the SCAT had quadratic responses but the measurements were increased and then decreased (quadratic, p<0.05). The expression of HSL in the LT was linearly decreased (p<0.05) with increasing of dietary n-6:n-3 PUFA ratio.ConclusionDietary n-6:n-3 PUFA ratio could regulate lipid and fatty acid metabolism in blood and tissue. Reducing dietary n-6:n-3 PUFA ratio (3:1) could appropriately suppress expression of related genes in PPARγ signaling, and result in improved growth performance and n-3 PUFA deposition in muscle and adipose tissue in finishing pigs.

Zero valent zinc regulates adipocyte differentiation through calpain family protein and peroxisome proliferator-activated receptor gamma signaling in mouse 3T3-L1 cells

In the present study, the zero valent zinc (ZVZ) was used in the field of tissue regeneration engineering by inducing the preadipocytes into mature adipocytes in mouse 3T3-L1 cells. Initially, the ZVZ nanoparticles was synthesized using chemical reduction method and confirmed by EDS spectrum analysis which showed the presence of zinc ion without any impurities. The XRD and Raman analysis showed the characteristic peaks of zinc with hexagonal structure and the strong phonon band attributed to ZVZ, respectively. The microscopic analysis showed the ZVZ nanoparticles are well dispersed with spherical shape and the size was found to between 85−95 nm. The in vitro cytotoxic activity of ZVZ against 3T3-L1 showed less toxicity in higher concentration and the results were compared with standard adipogenic stimulant dexamethasone. The oil red O staining assay morphologically confirmed the ZVZ induces adipogenesis in 3T3-L1 as well as increase the lipid accumulation during treatment with ZVZ. Moreover, the ZVZ upregulates the expression of adipogenic marker genes such as PPARγ, FABP4 and the calpain family protein during differentiation of preadipocytes into mature adipocytes. Together, the ZVZ regulates the differentiation in 3T3-L1 cells through PPARγ and calpain signaling pathway deciphers the role of ZVZ in tissue regeneration engineering.

Protective Effect of Fuzi Lizhong Decoction against Non-alcoholic Fatty Liver Disease via Anti-inflammatory Response through Regulating p53 and PPARG Signaling.

Fuzi Lizhong decoction (FLD) is derived from an ancient Chinese Pharmacopoeia and has been used in clinical treatment for years. The present study aimed to investigate the activities and underlying mechanisms of FLD against non-alcoholic fatty liver disease (NAFLD). Network pharmacology analysis demonstrated that FLD might affect NAFLD through regulating p53 and peroxisome proliferator activated receptor gamma (PPARG), which has been confirmed in vitro and in vivo. In vivo NAFLD was induced in rats by a high-fat diet, and in vitro studies were performed on HL-7702 cells treated with oleic acid and linoleic acid. We showed that FLD significantly improved NAFLD by regulating the immune system to induce the release of interleukin-10 (IL-10), interferon-α (IFN-α), and IFN-β through activating p53 signaling and inhibiting PPARG signaling in vivo and in vitro. P53 inhibition induced by NAFLD was recused by FLD, while PPARG overexpression induced by NAFLD was inhibited by FLD. In addition, NAFLD resulted in increased levels of total cholesterol, triglyceride, and blood glucose in the serum and free fatty acid in the liver, which were reduced by FLD treatment. Evidently, FLD exhibited potent protective effects against NAFLD via p53 and PPARG signaling. Our study could provide novel insights into the mechanisms of FLD as an anti-inflammatory candidate for the treatment of NAFLD in the future.

Fighting Diabetes Mellitus: Pharmacological and Non-pharmacological Approaches.

The increasing worldwide prevalence of diabetes mellitus confers heavy public health issues and points to a large medical need for effective and novel anti-diabetic approaches with negligible adverse effects. Developing effective and novel anti-diabetic approaches to curb diabetes is one of the most foremost scientific challenges. This article aims to provide an overview of current pharmacological and non-pharmacological approaches available for the management of diabetes mellitus. Research articles that focused on pharmacological and non-pharmacological interventions for diabetes were collected from various search engines such as Science Direct and Scopus, using keywords like diabetes, glucagon-like peptide-1, glucose homeostasis, etc. Results: We review in detail several key pathways and pharmacological targets (e.g., the G protein-coupled receptors- cyclic adenosine monophosphate, 5'-adenosine monophosphate-activated protein kinase, sodium-glucose cotransporters 2, and peroxisome proliferator activated-receptor gamma signaling pathways) that are vital in the regulation of glucose homeostasis. The currently approved diabetes medications, the pharmacological potentials of naturally occurring compounds as promising interventions for diabetes, and the non-pharmacological methods designed to mitigate diabetes are summarized and discussed. Pharmacological-based approaches such as insulin, metformin, sodium-glucose cotransporters 2 inhibitor, sulfonylureas, glucagon-like peptide-1 receptor agonists, and dipeptidyl peptidase IV inhibitors represent the most important strategies in diabetes management. These approved diabetes medications work via targeting the central signaling pathways related to the etiology of diabetes. Non-pharmacological approaches, including dietary modification, increased physical activity, and microbiota-based therapy are the other cornerstones for diabetes treatment. Pharmacological-based approaches may be incorporated when lifestyle modification alone is insufficient to achieve positive outcomes.

Atorvastatin protects against postoperative neurocognitive disorder via a peroxisome proliferator-activated receptor-gamma signaling pathway in mice.

ObjectivePostoperative neurocognitive disorder (PND) is a main complication that is commonly seen postoperatively in elderly patients. The underlying mechanism remains unclear, although neuroinflammation has been increasingly observed in PND. Atorvastatin is a pleiotropic agent with proven anti-inflammatory effects. In this study, we investigated the effects of atorvastatin on a PND mouse model after peripheral surgery.Material and methodsThe mice were randomized into five groups. The PND models were established, and an open field test and fear condition test were performed. Hippocampal inflammatory cytokine expression was determined using ELISA. Peroxisome proliferator-activated receptor-gamma (PPARγ) expression in the hippocampus was tested using qRT-PCR and western blot analysis.ResultsOn day 1 after surgery, inflammatory cytokines such as tumor necrosis factor-α, interleukin-1β, and interleukin-6 showed a significant increase in the hippocampus, with prominent cognitive impairment. Atorvastatin treatment improved cognitive function in the mouse model, attenuated neuroinflammation, and increased PPARγ expression in the hippocampus. However, treatment with the PPARγ antagonist GW9662 partially reversed the protective effects of atorvastatin.ConclusionsThese results indicated that atorvastatin improves several hippocampal functions and alleviates inflammation in PND mice after surgery, probably through a PPARγ-involved signaling pathway.

Obestatin ameliorates water retention in chronic heart failure by downregulating renal aquaporin 2 through GPR39, V2R and PPARG signaling

AimsObestatin regulates water metabolism by inhibiting arginine vasopressin (AVP) release and upregulated obestatin has been detected in patients with chronic heart failure (CHF). However, the significance of obestatin in CHF, particularly with regard to water retention and aquaporin 2 (AQP2) expression, remains unknown. Main methodsUsing a CHF rat model, the effects of 2-week exogenous obestatin administration were evaluated. Expression of AQP2 was evaluated by immunoblotting, immunohistochemical staining, and quantitative real-time PCR (qPCR) in CHF rat model and mouse inner medullary collecting duct (mIMCD) 3 cell line. Moreover, the influence of obestatin on the genetic transcription profile in mIMCD3 cells was evaluated by microarray, and the potential regulatory mechanisms of obestatin on AQP2 were evaluated by RNA silencing of vasopressin receptor 2 (V2R), peroxisome proliferator-activated receptor gamma (PPARG), and G protein-coupled receptor 39 (GPR39). Key findingsObestatin increased urinary output and improved expression of CHF biomarker without significantly altering cardiac function, plasma electrolyte concentrations, or the plasma AVP concentration. AQP2 expression was significantly reduced. The results of microarray analyses and qPCR indicated that mRNA levels of Aqp2, Pparg, and V2r were significantly decreased. Inhibition of V2r and Pparg mRNA further reduced the expression of AQP2, while the inhibitory efficacy of obestatin on AQP2 was significantly offset after Gpr39 knockdown. SignificanceLong-term treatment with obestatin improves water retention in CHF by increasing urinary output through downregulation of AQP2 expression in renal IMCD cells. These effects may be at least partially mediated by regulation of GPR39, V2R and PPARG signaling.

Adipose depot-specific effects of ileal interposition surgery in UCD-T2D rats: unexpected implications for obesity and diabetes.

Ileal interposition (IT) surgery delays the onset of diabetes in a rat model of type-2 diabetes (UCD-T2DM). Here, to gain a deeper understanding of the molecular events underlying the effects of IT surgery, we examined the changes in the proteome of four white adipose depots (retroperitoneal, mesenteric, inguinal, and epididymal) and plasma-free fatty acid profile in pre-diabetic rats 1.5 months following IT or sham surgery. The IT-mediated changes were exerted mainly in mesenteric fat and spanned from delayed adipocyte maturation to a neuroendocrine remodeling. Conversely, inguinal, retroperitoneal, and epididymal depots showed opposite trends consistent with increased adipocyte maturation and adipogenesis development prior to overt signs of diabetes, probably orchestrated by peroxisome proliferator-activated receptor gamma signaling and higher plasma n-6/n-3 free fatty acid ratios. The resulting scenario suggests a targeted use of surgical strategies that seek to delay or improve diabetes in order to manipulate adipose depot-specific responses to maximize the duration and beneficial effects of the surgery.

Activation of Peroxisome Proliferator-Activated Receptor Gamma and Disruption of Progesterone Synthesis of 2-Ethylhexyl Diphenyl Phosphate in Human Placental Choriocarcinoma Cells: Comparison with Triphenyl Phosphate.

2-Ethylhexyl diphenyl phosphate (EHDPP), an organophosphate flame retardant (OPFR), is frequently detected in human blood. In this study, the sensitive dual-luciferase reporter gene assay and molecular docking were used to investigate the activation of EHDPP to human peroxisome proliferator-activated receptor gamma (PPARG). Results show that EHDPP exhibited stronger PPARG activation (EC20: 2.04 μM) than triphenyl phosphate (TPhP) (EC20: 2.78 μM). EHDPP upregulated the gene expression of 3β-hydroxysteroid dehydrogenase type 1 (3β-HSD1) in human placental choriocarcinoma cells in a dose-dependent manner, and the lowest observable effective concentration was 10 μM, lower than that of TPhP (20 μM). EHDPP significantly altered progesterone secretion at a lower concentration (10 μM) than that of TPhP (20 μM), and both EHDPP and TPhP significantly promoted human chorionic gonadotropin (hCG) production at 20 μM. Furthermore, inactivation of PPARG by either a pharmacological inhibitor (GW9662) or small interfering RNA (siRNA) abolished the change in progesterone secretion and gene expression in the cells exposed to EHDPP, suggesting that the PPARG signaling pathway plays a role in the upregulation of progesterone by the two OPFRs. This is the first report to show that OPFRs can alter the biosynthesis of progesterone in the placenta, which could affect female reproduction and fetal development.

Bufei Yishen granules combined with acupoint sticking therapy suppress oxidative stress in chronic obstructive pulmonary disease rats: Via regulating peroxisome proliferator-activated receptor-gamma signaling

Ethnopharmacological relevanceTraditional Chinese medicine (TCM) is clinically used under the guidance of its unique theory system. Bufei Yishen (BY) granules, an oral Chinese herbal formula, is confirmed effective for treating the syndrome of lung-kidney qi deficiency in chronic obstructive pulmonary disease (COPD) patients. Shu-Fei Tie ointment is another prescription for acupoint sticking (AS) therapy based on the theory of treating an internal disease by external treatment on proper acupoints. The beneficial effects of BY granules combined with Shu-Fei Tie have been proved in previous clinical trials. However, the underlying mechanism remains unclear. The present study was initiated to explore the antioxidative mechanism of the integrated therapy of BY granules and acupoint sticking via regulating by peroxisome proliferator activated receptor-gamma (PPARγ) signaling in a cigarette-smoke/bacterial exposure induced COPD rat model. Materials and methodsRats were randomized into Control, Model, BY, AS, BY+AS and aminophylline (APL) groups. COPD rats were induced by cigarette-smoke and bacterial exposures, and were administrated with normal saline, BY granules, AS, BY+AS or aminophylline from week 9 and sacrificed at week 20. Activity of superoxide dismutase (SOD) and levels of methane dicarboxylic aldehyde (MDA) in peripheral blood and bronchoalveolar lavage fluid (BALF) were determined by hydroxylamine and thiobarbituric acid methods. The gene and protein expressions of PPARγ in the lung tissues were analyzed by quantitative polymerase chain reaction and western blot. ResultsSerum and BALF SOD decreased significantly in Model group (P<0.01), while MDA increased (P<0.01). Compared to COPD rats, serum SOD was higher in all treatment groups (P<0.01), and BALF SOD was higher in BY and BY+AS groups (P<0.01); serum and BALF MDA was lower in all treatment groups (P<0.01). Serum and BALF SOD was higher in BY+AS group than in AS group, while MDA was lower (P<0.05). BALF SOD increased in BY+AS group compared with APL group, while MDA decreased (P<0.05). PPARγ mRNA and protein and the phosphorylation of PPARγ (p-PPARγ) decreased in COPD rats (P<0.01), and increased in all treatment groups (P<0.01). PPARγ mRNA was higher in BY+AS group than in AS group (P<0.05), PPARγ and p-PPARγ were higher in BY+AS group than in AS and APL groups (P<0.05, P<0.01); PPARγ protein was higher in BY group than in APL group (P<0.05). ConclusionBufei Yishen granules, Shu-Fei Tie and their combination have beneficial effects in stable COPD, and can attenuate the oxidative stress, and the activation of PPARγ signaling might be involved in the underlying mechanisms, but there are no obvious synergistic effect of Bufei Yishen granules and Shu-Fei Tie.

Activation of Peroxisome Proliferator-activated Receptor γ Prevents Development of Heart Failure With Preserved Ejection Fraction; Inhibition of Wnt-β-catenin Signaling as a Possible Mechanism.

Left ventricular (LV) fibrosis plays an important role in the development of heart failure with preserved ejection fraction (HFpEF). We investigated whether chronic peroxisome proliferator-activated receptor gamma agonism with pioglitazone can prevent the development of HFpEF. We also evaluated the role of Wnt-β-catenin signaling in the development of HFpEF, and its relationship to peroxisome proliferator-activated receptor gamma signaling. Dahl salt-sensitive rats placed on an 8% NaCl diet from age 6 weeks were used as HFpEF model. Rats placed on 0.3% NaCl diet served as controls (n = 7). HFpEF model rats were randomized to no treatment (n = 7) or treatment with pioglitazone (2.5 mg/kg per day, n = 7) at age 13 weeks. Pioglitazone administration from age 13 to 21 weeks attenuated the development of LV fibrosis and stiffening (both P < 0.05), and subsequently prevented the development of HFpEF. In the untreated HFpEF model, Wnt1, 2, 10b messenger RNA and β-catenin protein expression levels in the left ventricle increased in the heart failure stage, along with the increase in type I collagen messenger RNA expression levels. Administration of pioglitazone attenuated the activation of Wnt-β-catenin signaling. Our results show that pioglitazone prevented the development of LV fibrosis and HFpEF in a rat model, at least partly due to attenuated Wnt-β-catenin signaling.

Breast Cancer Genetic and Molecular Subtype Impacts Response to Omega-3 Fatty Acid Ethyl Esters

ABSTRACTEpidemiological studies have correlated frequent omega-3 (n-3) fatty acid consumption with a lower risk for breast cancer; however, recent prospective studies have been less conclusive. Efforts in the preventive setting have focused on the use of n-3 fatty acids, and the pharmaceutical ethyl esters (EE) of these natural compounds, for high-risk patient populations. Limited understanding of specific mechanisms by which these agents function has hampered identification of the cancer subtype(s) that would gain the greatest therapeutic benefit. In this study, we investigated the in vitro effects of n-3 EEs in four distinct breast cancer subtypes and explored how they affect not only breast cancer cell survival but also modulate the nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB) and peroxisome proliferator-activated receptor gamma signaling pathways. Similar to the high variance in response observed in human studies, we found that the effectiveness of n-3 EEs depends on the molecular characteristics of the MCF-7, CAMA-1, MDA-MB-231, and SKBR3 breast cancer cell lines and is closely associated with the suppression of NF-κB. These data strongly suggest that the use of n-3 fatty acids and their pharmaceutical ether esters in the prevention and therapeutic setting should be guided by specific tumor characteristics.

MicroRNA-128 inhibition attenuates myocardial ischemia/reperfusion injury-induced cardiomyocyte apoptosis by the targeted activation of peroxisome proliferator-activated receptor gamma.

The aim of the present study was to investigate the effects of microRNA (miR)-128 inhibition on the targeted activation of peroxisome proliferator-activated receptor gamma (PPARG) and on cardiomyocyte apoptosis induced by myocardial ischemia/reperfusion (I/R) injury. In vitro, the expression of PPARG was detected by reverse transcription-quantitative polymerase chain reaction and western blotting in neonatal rat ventricular myocytes (NRVMs) and HEK293 cells transfected with the mimics or inhibitors of miR-128 or control RNA. Luciferase reporter assays were used to identify whether PPARG is a direct target of miR-128. In vivo, miR-128 was knocked down via ear vein injection of antagomir-128 in a rabbit myocardial I/R injury model. Western blotting investigated the activation of Akt [phosphorylated (p)-Akt] and the expression of total-Akt, PPARG and myeloid leukemia cell differentiation protein-1 (Mcl-1) in the myocardium. Cardiomyocyte apoptosis was examined with transmission electron microscropy and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. PPARG mRNA and protein were downregulated in NRVMs transfected with miR-128 mimics, but upregulated by antagomir-128 compared with control. This indicates that PPARG is a direct miR-128 target. Activation of Akt (p-Akt), Mcl-1 and PPARG expression in the myocardium were increased by miR-128 inhibition. Furthermore, miR-128 antagomirs significantly reduced apoptosis in hearts subjected to I/R injury, which was blocked by the PPARG inhibitor GW9662. In conclusion, miR-128 inhibition attenuated I/R injury-induced cardiomyocyte apoptosis by the targeted activation of PPARG signaling.

Telmisartan enhances mitochondrial activity and alters cellular functions in human coronary artery endothelial cells via AMP-activated protein kinase pathway

ObjectiveMitochondrial dysfunction plays an important role in cellular senescence and impaired function of vascular endothelium, resulted in cardiovascular diseases. Telmisartan is a unique angiotensin II type I receptor blocker that has been shown to prevent cardiovascular events in high risk patients. AMP-activated protein kinase (AMPK) plays a critical role in mitochondrial biogenesis and endothelial function. This study assessed whether telmisartan enhances mitochondrial function and alters cellular functions via AMPK in human coronary artery endothelial cells (HCAECs). Methods and resultsIn cultured HCAECs, telmisartan significantly enhanced mitochondrial activity assessed by mitochondrial reductase activity and intracellular ATP production and increased the expression of mitochondria related genes. Telmisartan prevented cellular senescence and exhibited the anti-apoptotic and pro-angiogenic properties. The expression of genes related anti-oxidant and pro-angiogenic properties were increased by telmisartan. Telmisartan increased endothelial NO synthase and AMPK phosphorylation. Peroxisome proliferator-activated receptor gamma signaling was not involved in telmisartan-induced improvement of mitochondrial function. All of these effects were abolished by inhibition of AMPK. ConclusionsTelmisartan enhanced mitochondrial activity and exhibited anti-senescence effects and improving endothelial function through AMPK in HCAECs. Telmisartan could provide beneficial effects on vascular diseases via enhancement of mitochondrial activity and modulating endothelial function through AMPK activation.

Peroxisome proliferator-activated receptor gamma signaling in human sperm physiology.

Peroxisome proliferator-activated receptor gamma (PPARγ) is a member of the PPARs, which are transcription factors of the steroid receptor superfamily. PPARγ acts as an important molecule for regulating energy homeostasis, modulates the hypothalamic-pituitary-gonadal (HPG) axis, and is reciprocally regulated by HPG. In the human, PPARγ protein is highly expressed in ejaculated spermatozoa, implying a possible role of PPARγ signaling in regulating sperm energy dissipation. PPARγ protein is also expressed in Sertoli cells and germ cells (spermatocytes). Its activation can be induced during capacitation and the acrosome reaction. This mini-review will focus on how PPARγ signaling may affect fertility and sperm quality and the potential reversibility of these adverse effects.