Association between genetically proxied PPARG activation and psoriasis vulgaris: a Mendelian randomization study

BACKGROUND

Psoriasis is a common autoimmune disease in clinical practice, and previous observational studies have suggested that PPARG agonists such as Pioglitazone may be potential therapeutic agents. However, due to interference from various confounding factors, different observational studies have not reached a unified conclusion. We aim to evaluate the potential use of PPARG agonists for treating psoriasis from a new perspective through drug-targeted Mendelian randomization (MR) analysis.

MATERIALS AND METHODS

This study includes data on 8,876 individuals for acute myocardial infarction from GWAS, and LDL cholesterol data from 343,621 Europeans. FinnGen contributed psoriasis vulgaris data for 403,972 individuals. The DrugBank10 databases function to identify genes encoding protein products targeted by active constituents of lipid-modifying targets. A two-sample MR analysis and summary-data-based MR (SMR) analysis estimated the associations between expressions of drug target genes and symptoms of psoriasis vulgaris. A multivariable MR study was further conducted to examine if the observed association was direct association.

RESULTS

SMR analysis revealed that enhanced PPARG gene expression in the blood (equivalent to a one standard deviation increase) was a protective factor for psoriasis vulgaris (beta = -0.2017, se = 0.0723, p = 0.0053). Besides, there exists an MR association between LDL mediated by PPARG and psoriasis vulgaris outcomes (beta = -3.9169, se = 0.5676, p = 5.17E-12). These results indicate that PPARG is a therapeutic target for psoriasis, suggesting that psoriasis may be a potential indication for PPARG agonists.

CONCLUSION

This study confirms that therapeutic activation of PPARG helps suppress the development of psoriasis. Psoriasis may be a new indication for PPARG agonists, such as Pioglitazone. In the future, new anti-psoriatic drugs could be developed targeting PPARG.

Identification and experimental validation of immune-related gene PPARG is involved in ulcerative colitis

BACKGROUND

The pathophysiology of ulcerative colitis (UC) is believed to be heavily influenced by immunology, which presents challenges for both diagnosis and treatment. The main aims of this study are to deepen our understanding of the immunological characteristics associated with the disease and to identify valuable biomarkers for diagnosis and treatment.

METHODS

The UC datasets were sourced from the GEO database and were analyzed using unsupervised clustering to identify different subtypes of UC. Twelve machine learning algorithms and Deep learning model DNN were developed to identify potential UC biomarkers, with the LIME and SHAP methods used to explain the models' findings. PPI network is used to verify the identified key biomarkers, and then a network connecting super enhancers, transcription factors and genes is constructed. Single-cell sequencing technology was utilized to investigate the role of Peroxisome Proliferator Activated Receptor Gamma (PPARG) in UC and its correlation with macrophage infiltration. Furthermore, alterations in PPARG expression were validated through Western blot (WB) and immunohistochemistry (IHC) in both in vitro and in vivo experiments.

RESULT

By utilizing bioinformatics techniques, we were able to pinpoint PPARG as a key biomarker for UC. The expression of PPARG was significantly reduced in cell models, UC animal models, and colitis models induced by dextran sodium sulfate (DSS). Interestingly, overexpression of PPARG was able to restore intestinal barrier function in H2O2-induced IEC-6 cells. Additionally, immune-related differentially expressed genes (DEGs) allowed for efficient classification of UC samples into neutrophil and mitochondrial metabolic subtypes. A diagnostic model incorporating the three disease-specific genes PPARG, PLA2G2A, and IDO1 demonstrated high accuracy in distinguishing between the UC group and the control group. Furthermore, single-cell analysis revealed that decreased PPARG expression in colon tissue may contribute to the polarization of M1 macrophages through activation of inflammatory pathways.

CONCLUSION

In conclusion, PPARG, a gene related to immunity, has been established as a reliable potential biomarker for the diagnosis and treatment of UC. The immune response it controls plays a key role in the progression and development of UC by enabling interaction between characteristic biomarkers and immune infiltrating cells.

A Characterization and Functional Analysis of Peroxisome Proliferator-Activated Receptor Gamma Splicing Variants in the Buffalo Mammary Gland

Peroxisome proliferator-activated receptor γ (PPARG) has various splicing variants and plays essential roles in the regulation of adipocyte differentiation and lipogenesis. However, little is known about the expression pattern and effect of the PPARG on milk fat synthesis in the buffalo mammary gland. In this study, we found that only PPARG-X17 and PPARG-X21 of the splicing variant were expressed in the buffalo mammary gland. Amino acid sequence characterization showed that the proteins encoded by PPARG-X17 and PPARG-X21 are endonuclear non-secreted hydrophilic proteins. Protein domain prediction found that only the PPARG-X21-encoded protein had PPAR ligand-binding domains (NR_LBD_PPAR), which may lead to functional differences between the two splices. RNA interference (RNAi) and the overexpression of PPARG-X17 and PPARG-X21 in buffalo mammary epithelial cells (BMECs) were performed. Results showed that the expression of fatty acid synthesis-related genes (ACACA, CD36, ACSL1, GPAT, AGPAT6, DGAT1) was significantly modified (p < 0.05) by the RNAi and overexpression of PPARG-X17 and PPARG-X21. All kinds of FAs detected in this study were significantly decreased (p < 0.05) after RNAi of PPARG-X17 or PPARG-X21. Overexpression of PPARG-X17 or PPARG-X21 significantly decreased (p < 0.05) the SFA content, while significantly increased (p < 0.05) the UFA, especially the MUFA in the BMECs. In conclusion, there are two PPARG splicing variants expressed in the BMECs that can regulate FA synthesis by altering the expression of diverse fatty acid synthesis-related genes. This study revealed the expression characteristics and functions of the PPARG gene in buffalo mammary glands and provided a reference for further understanding of fat synthesis in buffalo milk.

PPARG is dispensable for bovine embryo development up to tubular stages

Following blastocyst hatching, ungulate embryos undergo a prolonged preimplantation period termed conceptus elongation. Conceptus elongation constitutes a highly susceptible period for embryonic loss and the embryonic requirements during this process are largely unknown, but multiple lipid compounds have been identified in the fluid nourishing the elongating conceptuses. Peroxisome proliferator-activated receptors (PPARs) mediate the signaling actions of prostaglandins and other lipids and, between them, PPARG has been pointed out to play a relevant role on conceptus elongation by a functional study that depleted PPARG in both uterus and conceptus. The objective of this study has been to determine if embryonic PPARG is required for bovine embryo development. To that aim, we have generated bovine PPARG KO embryos in vitro by two independent gene ablation strategies and assess their developmental ability. In vitro development to Day (D) 8 blastocyst was unaffected by PPARG ablation, as total, inner cell mass and trophectoderm cell numbers were similar between WT and KO D8 embryos. In vitro post-hatching development to D12 was also comparable between different genotypes, as embryo diameter, epiblast cell number, and embryonic disc formation and hypoblast migration rates were unaffected by the ablation. The development to tubular stages equivalent to E14 was assessed in vivo, following a heterologous embryo transfer experiment, observing that the development of extra-embryonic membranes and of the embryonic disc was not altered by PPARG ablation. In conclusion, PPARG ablation did not impaired bovine embryo development up to tubular stages.

PPARG-mediated autophagy activation alleviates inflammation in rheumatoid arthritis

INTRODUCTION

Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disease characterized by joint inflammation and bone damage, that not only restricts patient activity but also tends to be accompanied by a series of complications, seriously affecting patient prognosis. Peroxisome proliferator-activated receptor gamma (PPARG), a receptor that controls cellular metabolism, regulates the function of immune cells and stromal cells. Previous studies have shown that PPARG is closely related to the regulation of inflammation. However, the role of PPARG in regulating the pathological processes of RA is poorly understood.

MATERIALS AND METHODS

PPARG expression was examined in the synovial tissues and peripheral blood mononuclear cells (PBMCs) from RA patients and the paw of collagen-induced arthritis (CIA) model rats. Molecular biology experiments were designed to examine the effect of PPARG and cannabidiol (CBD) on RAW264.7 cells and CIA rats.

RESULTS

The results reveal that PPARG accelerates reactive oxygen species (ROS) clearance by promoting autophagy, thereby inhibiting ROS-mediated macrophage polarization and NLRP3 inflammasome activation. Notably, CBD may be a promising candidate for understanding the mechanism by which PPARG regulates autophagy-mediated inflammation.

CONCLUSIONS

Taken together, these findings indicate that PPARG may have a role for distinguishing between RA patients and healthy control, and for distinguishing RA activity; moreover, PPARG could be a novel pharmacological target for alleviating RA through the mediation of autophagy. CBD can act as a PPARG agonist that alleviates the inflammatory progression of RA.

Hypermethylation of PPARG-encoding gene promoter mediates fine particulate matter-induced pulmonary fibrosis by regulating the HMGB1/NLRP3 axis

The inflammatory response induced by fine particulate matter (PM2.5), a common class of air pollutants, is an important trigger for the development of pulmonary fibrosis. However, the specific mechanisms responsible for this phenomenon are yet to be fully understood. To investigate the mechanisms behind the onset and progression of lung fibrosis owing to PM2.5 exposure, both rats and human bronchial epithelial cells were subjected to varying concentrations of PM2.5. The involvement of the PPARG/HMGB1/NLRP3 signaling pathway in developing lung fibrosis caused by PM2.5 was validated through the utilization of a PPARG agonist (rosiglitazone), a PPARG inhibitor (GW9662), and an HMGB1 inhibitor (glycyrrhizin). These outcomes highlighted the downregulation of PPARG expression and activation of the HMGB1/NLRP3 signaling pathway triggered by PM2.5, thereby eliciting inflammatory responses and promoting pulmonary fibrosis. Additionally, PM2.5 exposure-induced DNA hypermethylation of PPARG-encoding gene promoter downregulated PPARG expression. Moreover, the DNA methyltransferase inhibitor 5-azacytidine mitigated the hypermethylation of the PPARG-encoding gene promoter triggered by PM2.5. In conclusion, the HMGB1/NLRP3 signaling pathway was activated in pulmonary fibrosis triggered by PM2.5 through the hypermethylation of the PPARG-encoding gene promoter.

PPARG activation promotes the proliferation of colorectal cancer cell lines and enhances the antiproliferative effect of 5-fluorouracil

BACKGROUND

Peroxisome proliferator-activated receptor gamma (PPARG) is a member of the nuclear receptor family. It is involved in the regulation of adipogenesis, lipid metabolism, insulin sensitivity, vascular homeostasis and inflammation. In addition, PPARG agonists, known as thiazolidinediones, are well established in the treatment of type 2 diabetes mellitus. PPARGs role in cancer is a matter of debate, as pro- and anti-tumour properties have been described in various tumour entities. Currently, the specific role of PPARG in patients with colorectal cancer (CRC) is not fully understood.

MATERIAL AND METHODS

The prognostic impact of PPARG expression was investigated by immunohistochemistry in a case-control study using a matched pair selection of CRC tumours (n = 246) with either distant metastases to the liver (n = 82), lung (n = 82) or without distant metastases (n = 82). Its effect on proliferation as well as the sensitivity to the chemotherapeutic drug 5-fluorouracil (5-FU) was examined after activation, inhibition, and transient gene knockdown of PPARG in the CRC cell lines SW403 and HT29.

RESULTS

High PPARG expression was significantly associated with pulmonary metastasis (p = 0.019). Patients without distant metastases had a significantly longer overall survival with low PPARG expression in their tumours compared to patients with high PPARG expression (p = 0.045). In the pulmonary metastasis cohort instead, a trend towards longer survival was observed for patients with high PPARG expression in their tumour (p = 0.059). Activation of PPARG by pioglitazone and rosiglitazone resulted in a significant dose-dependent increase in proliferation of CRC cell lines. Inhibition of PPARG by its specific inhibitor GW9662 and siRNA-mediated knockdown of PPARG significantly decreased proliferation. Activating PPARG significantly increased the CRC cell lines sensitivity to 5-FU while its inhibition decreased it.

CONCLUSION

The prognostic effect of PPARG expression depends on the metastasis localization in advanced CRC patients. Activation of PPARG increased malignancy associated traits such as proliferation in CRC cell lines but also increases sensitivity towards the chemotherapeutic agent 5-FU. Based on this finding, a combination therapy of PPARG agonists and 5-FU-based chemotherapy constitutes a promising strategy which should be further investigated.

Context-dependent regulation of lipid accumulation in adipocytes by a HIF1α-PPARγ feedback network

Hypoxia-induced upregulation of HIF1α triggers adipose tissue dysfunction and insulin resistance in obese patients. HIF1α closely interacts with PPARγ, the master regulator of adipocyte differentiation and lipid accumulation, but there are conflicting results regarding how this interaction controls the excessive lipid accumulation that drives adipocyte dysfunction. To directly address these conflicts, we established a differentiation system that recapitulated prior seemingly opposing observations made across different experimental settings. Using single-cell imaging and coarse-grained mathematical modeling, we show how HIF1α can both promote and repress lipid accumulation during adipogenesis. Our model predicted and our experiments confirmed that the opposing roles of HIF1α are isolated from each other by the positive-feedback-mediated upregulation of PPARγ that drives adipocyte differentiation. Finally, we identify three factors: strength of the differentiation cue, timing of hypoxic perturbation, and strength of HIF1α expression changes that, when considered together, provide an explanation for many of the previous conflicting reports.

PPARG, GNG12, and CD19 are potential independent predictors of central nerve recurrence in childhood acute lymphoblastic leukemia

OBJECTIVE

To identify biomarkers that can predict the recurrence of the central nervous system (CNS) in children with acute lymphoblastic leukemia (ALL).

MATERIALS AND METHODS

The transcriptome and clinical data of ALL in children were downloaded from the TARGET database. Transcriptome data were analyzed by bioinformatics method to identify core (hub) genes and establish a risk assessment model. Univariate Cox analysis was performed on each clinical data, and multivariate Cox regression analysis was performed on the obtained results and risk score. The children ALL phase I samples from TARGET database were used for validation.

RESULTS

Univariate multivariate Cox analysis of 10 hub genes identified showed that PPARG (HR = 0.78, 95%CI = 0.67-0.91, p = 0.007), CD19 (HR = 1.15, 95%CI = 1.05-1.26, p = 0.003) and GNG12 (HR = 1.25, 95%CI = 1.04-1.51, p = 0.017) had statistical differences. The risk score was statistically significant in univariate (HR = 3.06, 95%CI = 1.30-7.19, p = 0.011) and multivariate (HR = 1.81, 95%CI = 1.16-2.32, p = 0.046) Cox regression analysis. The survival analysis results of the high and low-risk groups were different when the validation dataset was substituted into the model (p = 0.018). Then, we constructed a Nomogram which had a concordance index of survival prediction of 0.791(95%CI= 0.779-0.803). In addition, the CNS involvement grading status at first diagnosis CNS3 vs. CNS1 (HR = 5.74, 95%CI = 2.01-16.4, p = 0.001), T cell vs B cell (HR = 1.63, 95% CI = 1.06-2.49, p = 0.026) were also statistically significant.

CONCLUSIONS

PPARG, GNG12, and CD19 may be predictors of CNS relapse in childhood ALL.

Brucea Javanica Oil Emulsion Injection inhibits proliferation of pancreatic cancer via regulating apoptosis-related genes

Brucea Javanica Oil Emulsion Injection (BJOEI) has been proven to have extensive anti-tumor effects. But the anti-cancer mechanisms need further exploration. So, the aim of this study was to investigate the role and mechanisms of BJOEI on pancreatic cancer using network pharmacology and experimental validation. Disease targets were obtained from the GSE101448 dataset in the Gene Expression Omnibus (GEO) database. Eight active ingredients were identified following a comprehensive literature search. The target genes of BJOEI were obtained from the SwissTarget Prediction database. The core targets of BJOEI and the involved signaling pathways were determined using the compound-target network, protein-protein interaction (PPI) network, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. GO and KEGG enrichment analyses of 50 potential overlapping genes indicated that BJOEI exerted therapeutic effects on pancreatic cancer through the apoptotic pathway. In vitro experiments further revealed that BJOEI could suppress cell growth and invasion, arrest cells at the S stage, and cause cell apoptosis in three pancreatic cell lines. Additionally, BJOEI inhibited tumor growth in vivo. Among the 15 key genes regulating apoptosis, 11 were upregulated, while 4 were downregulated. PPARG emerged as a core target in bioinformatics analysis. The ability of PPARG to regulate apoptosis was validated by Western Blot. Our findings verified that BJOEI could regulate apoptosis-related genes, especially PPARG, thereby inducing apoptosis and inhibiting proliferation in pancreatic cancer cells. BJOEI can impede pancreatic cancer progression and induce cell apoptosis. The underlying mechanism appears to be closely associated with the regulation of apoptosis-related genes.

Integrated investigation and experimental validation of PPARG as an oncogenic driver: implications for prognostic assessment and therapeutic targeting in hepatocellular carcinoma

Peroxisome proliferator-activated receptor gamma (PPARG), a key transcription factor involved in lipid metabolism and glucose homeostasis, has been implicated in various types of cancer. However, its precise role in cancer remains unclear. In this study, we conducted a comprehensive pan-cancer analysis of PPARG expression using various types of cancer obtained from public databases. We observed significant heterogeneity in PPARG expression across different types of cancer. The association between PPARG expression and patient prognosis was investigated using Cox proportional hazards regression models and survival analysis. Clinical features and protein expression levels in the cohort showed that PPARG expression was strongly associated, suggesting its potential as a therapeutic target. We also evaluated the prognostic potential of PPARG by analyzing immune infiltration and genomic stability. We experimentally validated the potential of PPARG as a therapeutic target by analyzing drug sensitivity profiles, molecular docking simulations, and in vitro cell proliferation assays associated with PPARG expression. We identified common expression patterns of PPARG with other genes involved in key carcinogenic pathways. This provides deeper insights into the molecular mechanisms underlying its carcinogenic role. Additionally, functional enrichment analysis revealed significant enrichment of genes related to drug metabolism, cell proliferation, and immune response pathways associated with PPARG. Our findings highlight the importance of PPARG in the broader biology of cancer and suggest its potential as a diagnostic and therapeutic target for specific types of cancer. The results of our study provide strong support for the potential role of PPARG as a promising prognostic biomarker and immunotherapeutic target across various types of cancer.

New role for the anandamide metabolite prostaglandin F2α ethanolamide: Rolling preadipocyte proliferation

White adipose tissue regulation is key to metabolic health, yet still perplexing. The chief endocannabinoid anandamide metabolite, prostaglandin F2α ethanolamide (PGF2αEA), inhibits adipogenesis, that is, the formation of mature adipocytes. We observed that adipocyte progenitor cells-preadipocytes-following treatment with PGF2αEA yielded larger pellet sizes. Thus, we hypothesized that PGF2αEA might augment preadipocyte proliferation. Cell viability MTT and crystal violet assays, cell counting, and 5-bromo-2'-deoxyuridine incorporation in cell proliferation ELISA analyses confirmed our prediction. Additionally, we discovered that PGF2αEA promotes cell cycle progression through suppression of the expression of cell cycle inhibitors, p21 and p27, as shown by flow cytometry and qPCR. Enticingly, concentrations of this compound that showed no visible effect on cell proliferation or basal transcriptional activity of peroxisome proliferator-activated receptor gamma could, in contrast, reverse the anti-proliferative and peroxisome proliferator-activated receptor gamma-transcription activating effects of rosiglitazone (Rosi). MTT and luciferase reporter examinations supported this finding. The PGF2αEA pharmaceutical analog, bimatoprost, was also investigated and showed very similar effects. Importantly, we suggest the implication of the mitogen-activated protein kinase pathway in these effects, as they were blocked by the selective mitogen-activated protein kinase kinase inhibitor, PD98059. We propose that PGF2αEA is a pivotal regulator of white adipose tissue plasticity, acting as a regulator of the preadipocyte pool in adipose tissue.

IGF1 and PPARG polymorphisms are associated with reduced estimated glomerular filtration rate in a cohort of children and adolescents with type 1 diabetes

INTRODUCTION

Several genetic loci have been associated with diabetic nephropathy; however, the underlying genetic mechanisms are still poorly understood, with no robust candidate genes identified yet.

AIM

We aimed to determine whether two polymorphisms, previously associated with renal decline, influence kidney impairment evaluating their association with markers of renal function in a pediatric population with type 1 diabetes (T1D).

MATERIAL AND METHODS

Renal function was evaluated by glomerular filtration rate (eGFR) and albumin-to-creatinine ratio (ACR) in a cohort of pediatric subjects with T1D (n = 278). Risk factors for diabetes complications (diabetes duration, blood pressure, HbA1c) were assessed. The IGF1 rs35767 and PPARG rs1801282 SNPs were genotyped by TaqMan RT-PCR system. An additive genetic interaction was calculated. Association analysis between markers of renal function and both SNPs or their additive interaction were performed.

RESULTS

Both SNPs showed a significant association with eGFR: the A allele of rs35767 or the C allele of rs1801282 were associated to reduced eGFR compared to G alleles. Multivariate regression analysis adjusted for age, sex, z-BMI, T1D duration, blood pressure and Hba1c values showed that the additive genetic interaction was independently associated with lower eGFR (β = -3.59 [-6.52 to -0.66], p = 0.017). No associations were detected between SNPs, their additive interaction and ACR.

CONCLUSIONS

These results provide new insight into the genetic predisposition to renal dysfunction, showing that two polymorphisms in IGF1 and PPARG genes can lead to a reduction in renal filtration rate leading these patients to be exposed to a higher risk of early renal complications.

A network pharmacology-based approach to explore the effect of dihydromyricetin on non-alcoholic fatty liver rats via regulating PPARG and CASP3

BACKGROUND

Non-alcohol fatty liver disease (NAFLD) is the most prevalent hepatopathy in China, with few effective cures currently. This work aimed to confirm the effect of DHM in vivo/vitro and explore the potential mechanism based on a network pharmacology-based approach.

METHODS

The rats were fed using a high-fat diet (HFD) to accumulate lipid. DHM at different concentrations was used to treat the HFD rats. The serum total cholesterol (TC), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were detected using ELISA kits. The target genes of DHM against NAFLD were screened by online databases. Then, the cytotoxicity of DHM in primary hepatocytes and HepG2 cells was determined by MTT reagent. qRT-PCR was used to quantify the expression level of PPAGR and CASP3 mRNA. Cell apoptosis and intracellular triglyceride (TG) were detected.

RESULTS

HFD diet increased rat liver weight/body weight ratio, serum TC, ALT, and AST. But DHM treatment can reduce these elevated indicators. DHM targeted 14 potential genes in NAFLD. PPARG and CASP3 were two hub genes for DHM against NAFLD, with score factor coefficients of -7.1 and -6.8 kcal/mol. DHM reduced the increased PPARG mRNA level and intracellular TG induced by palmitic acid. DHM can reduce the increased CASP3 mRNA level and cell apoptosis induced by palmitic acid.

CONCLUSION

This work demonstrates a mechanism of DHM that alleviates lipid metabolism disorder and cell apoptosis for the treatment of NAFLD, evidencing the potential application of DHM in NAFLD.

PPARG stimulation restored lung mRNA expression of core clock, inflammation- and metabolism-related genes disrupted by reversed feeding in male mice

The circadian rhythm system regulates lung function as well as local and systemic inflammations. The alteration of this rhythm might be induced by a change in the eating rhythm. Peroxisome proliferator-activated receptor gamma (PPARG) is a key molecule involved in circadian rhythm regulation, lung functions, and metabolic processes. We described the effect of the PPARG agonist pioglitazone (PZ) on the diurnal mRNA expression profile of core circadian clock genes (Arntl, Clock, Nr1d1, Cry1, Cry2, Per1, and Per2) and metabolism- and inflammation-related genes (Nfe2l2, Pparg, Rela, and Cxcl5) in the male murine lung disrupted by reversed feeding (RF). In mice, RF disrupted the diurnal expression pattern of core clock genes. It decreased Nfe2l2 and Pparg and increased Rela and Cxcl5 expression in lung tissue. There were elevated levels of IL-6, TNF-alpha, total cells, macrophages, and lymphocyte counts in bronchoalveolar lavage (BAL) with a significant increase in vascular congestion and cellular infiltrates in male mouse lung tissue. Administration of PZ regained the diurnal clock gene expression, increased Nfe2l2 and Pparg expression, and reduced Rela, Cxcl5 expression and IL-6, TNF-alpha, and cellularity in BAL. PZ administration at 7 p.m. was more efficient than at 7 a.m.

Identification and Characteristics of Novel Mutations in Nonsyndromic Monogenic Obesity

Nonsyndromic monogenic obesity (NSMO) is a class of individual obesity that is independent of the environment and caused by a single gene mutation. It is mostly caused by mutations in LEP, LEPR, PCSK1, as well as some rare mutations in UCP3, NR0B2, and PPARG. Among 30 obesity patients, five patients are identified with positive gene detection. For the first time, the c.624C>T mutation associated with PCSK1, and the c.50G>A and c.293_301delinsAC mutations associated with NR0B2, as well as the obesity phenotype mutation (c.284A>G) associated with PPARG is confirmed. Following this, the genotype-clinical phenotype, mutation hotspots, and mutation distributions of each gene are summarized, and the genetic characteristics of NSMO are analyzed. The locations of mutation c.50G>A, and c.284A>G are highly conserved according to the sequencing alignment. According to the findings, the c.624C>T mutation in PCSK1 is a newly discovered synonymous mutation, but it can result in significant early-onset obesity. Additionally, the mutation of c.284A>G(PPARG) can lead to a variety of clinical phenotypes and the mutation of UCP3 and NR0B2 may increase the risk of type 2 diabetes mellitus. This study enriches the human NSMO gene mutation database and provides a scientific basis for clinically accurate diagnosis and treatment.

Genetically proxied glucose-lowering drug target perturbation and risk of cancer: a Mendelian randomisation analysis

AIMS/HYPOTHESIS

Epidemiological studies have generated conflicting findings on the relationship between glucose-lowering medication use and cancer risk. Naturally occurring variation in genes encoding glucose-lowering drug targets can be used to investigate the effect of their pharmacological perturbation on cancer risk.

METHODS

We developed genetic instruments for three glucose-lowering drug targets (peroxisome proliferator activated receptor γ [PPARG]; sulfonylurea receptor 1 [ATP binding cassette subfamily C member 8 (ABCC8)]; glucagon-like peptide 1 receptor [GLP1R]) using summary genetic association data from a genome-wide association study of type 2 diabetes in 148,726 cases and 965,732 controls in the Million Veteran Program. Genetic instruments were constructed using cis-acting genome-wide significant (p<5×10-8) SNPs permitted to be in weak linkage disequilibrium (r2<0.20). Summary genetic association estimates for these SNPs were obtained from genome-wide association study (GWAS) consortia for the following cancers: breast (122,977 cases, 105,974 controls); colorectal (58,221 cases, 67,694 controls); prostate (79,148 cases, 61,106 controls); and overall (i.e. site-combined) cancer (27,483 cases, 372,016 controls). Inverse-variance weighted random-effects models adjusting for linkage disequilibrium were employed to estimate causal associations between genetically proxied drug target perturbation and cancer risk. Co-localisation analysis was employed to examine robustness of findings to violations of Mendelian randomisation (MR) assumptions. A Bonferroni correction was employed as a heuristic to define associations from MR analyses as 'strong' and 'weak' evidence.

RESULTS

In MR analysis, genetically proxied PPARG perturbation was weakly associated with higher risk of prostate cancer (for PPARG perturbation equivalent to a 1 unit decrease in inverse rank normal transformed HbA1c: OR 1.75 [95% CI 1.07, 2.85], p=0.02). In histological subtype-stratified analyses, genetically proxied PPARG perturbation was weakly associated with lower risk of oestrogen receptor-positive breast cancer (OR 0.57 [95% CI 0.38, 0.85], p=6.45×10-3). In co-localisation analysis, however, there was little evidence of shared causal variants for type 2 diabetes liability and cancer endpoints in the PPARG locus, although these analyses were likely underpowered. There was little evidence to support associations between genetically proxied PPARG perturbation and colorectal or overall cancer risk or between genetically proxied ABCC8 or GLP1R perturbation with risk across cancer endpoints.

CONCLUSIONS/INTERPRETATION

Our drug target MR analyses did not find consistent evidence to support an association of genetically proxied PPARG, ABCC8 or GLP1R perturbation with breast, colorectal, prostate or overall cancer risk. Further evaluation of these drug targets using alternative molecular epidemiological approaches may help to further corroborate the findings presented in this analysis.

DATA AVAILABILITY

Summary genetic association data for select cancer endpoints were obtained from the public domain: breast cancer ( https://bcac.ccge.medschl.cam.ac.uk/bcacdata/ ); and overall prostate cancer ( http://practical.icr.ac.uk/blog/ ). Summary genetic association data for colorectal cancer can be accessed by contacting GECCO (kafdem at fredhutch.org). Summary genetic association data on advanced prostate cancer can be accessed by contacting PRACTICAL (practical at icr.ac.uk). Summary genetic association data on type 2 diabetes from Vujkovic et al (Nat Genet, 2020) can be accessed through dbGAP under accession number phs001672.v3.p1 (pha004945.1 refers to the European-specific summary statistics). UK Biobank data can be accessed by registering with UK Biobank and completing the registration form in the Access Management System (AMS) ( https://www.ukbiobank.ac.uk/enable-your-research/apply-for-access ).

PPARG: A Novel Target for Yellow Tea in Kidney Stone Prevention

Kidney stones are a common urological disorder with increasing prevalence worldwide. The treatment of kidney stones mainly relies on surgical procedures or extracorporeal shock wave lithotripsy, which can effectively remove the stones but also result in some complications and recurrence. Therefore, finding a drug or natural compound that can prevent and treat kidney stones is an important research topic. In this study, we aimed to investigate the effects of yellow tea on kidney stone formation and its mechanisms of action. We induced kidney stones in rats by feeding them an ethylene glycol diet and found that yellow tea infusion reduced crystal deposits, inflammation, oxidative stress, and fibrosis in a dose-dependent manner. Through network pharmacology and quantitative structure-activity relationship modeling, we analyzed the interaction network between the compounds in yellow tea and kidney stone-related targets and verified it through in vitro and in vivo experiments. Our results showed that flavonoids in yellow tea could bind directly or indirectly to peroxisome proliferator-activated receptor gamma (PPARG) protein and affect kidney stone formation by regulating PPARG transcription factor activity. In conclusion, yellow tea may act as a potential PPARG agonist for the prevention and treatment of renal oxidative damage and fibrosis caused by kidney stones.

Evaluation of Expression Levels of NFATc2 and PPARG Genes Two Effector Elements of WNT Pathway in Non-Small Cell Lung Carcinoma

Background

There is an emergency need in discovering an efficient profile of molecular biomarkers for early diagnosis of Non-small cell lung cancer (NSCLC). Transcription factors as important groups of regulators that are able to adjust the cell cycles have attracted the attention of most researchers recently. NFATc2 and PPARG are two important factors that have been selected for this project to assess their potential for being a biomarker for NSCLC.

Materials and Methods

Here in this study, 50 NSCLC patients were included. During bronchoscopy, which was their routine diagnostic approach, we collected tumoral and marginal normal tissues. After the extraction of the total RNA from the tissues, cDNA was synthesized, and the transcriptional level of NFATc2 and PPARG was examined by quantitative real-time PCR. Subsequently, the data were analyzed by proper statistical analyses.

Results

The mRNA expression of NFATc2 and PPARG were down-regulated in biopsy tissues of NSCLC patients compared with their pair marginal tissues (Pvalues were 0.0011 and <0.0001 respectively). Moreover, both of them had significant AUC (area under the curve) in the ROC curve analysis (0.65 for NFATc2 and 0.81 for PPARG, Pvalue <0.05).

Conclusion

It appears that mRNA expression of NFATc2 and PPARG possesses the potential to be regarded as a diagnostic or prognostic biomarker for NSCLC.

[AdipoRon Effect on Expression of Lipid Metabolism Genes in Cultured Human Primary Macrophages]

Atherosclerosis is characterized by excessive uptake of cholesterol-rich low-density lipoprotein (LDL) by vascular wall macrophages. The macrophages are transformed into foam cells, lipids accumulate in the intima of arteries, atherosclerotic plaques arise, and cardiovascular diseases develop. Adiponectin is an adipose tissue adipokine and possess anti-atherogenic and anti-inflammatory activities, which are mediated by adiponectin binding to its receptors AdipoR1 and AdipoR2. To exert its anti-atherogenic effect, adiponectin may regulate the reverse cholesterol transport and prevent foam cells formation. The small-molecule adiponectin receptor agonist AdipoRon was assumed to modulate expression of reverse cholesterol transport and inflammation genes in human macrophages. Several AdipoRon concentrations (0, 5, 10, and 20 μM) were tested for effect on expression of the lipid metabolism genes ABCA1, ABCG1, APOA1, NR1H3 (LXRα), NR1H2 (LXRβ), PPARG, and ACAT1 and the inflammation genes IL6, TNFA, and TLR4 in cultured human primary macrophages and the THP-1 macrophage cell line. Cell viability was measured using the MTS assay. ABCA1, ABCG1, APOA1, NR1H3, NR1H2, PPARG, ACAT1, IL6, TNFA, and TLR4 mRNA levels in human primary macrophages were assessed by real-time PCR. The PPARG and ABCA1 relative mRNA levels were found to increase in human primary macrophages treated with 5 or 10 μM AdipoRon for 24 h. A higher AdipoRon concentration (20 μM) was cytotoxic to macrophages, especially THP-1 cells. The effect of AdipoRon on human macrophages and potential adiponectin receptor agonists are of interest to study in view of the need to develop new approaches to atherosclerosis prevention and treatment.

Correlation between PPARG Pro12Ala Polymorphism and Therapeutic Responses to Thiazolidinediones in Patients with Type 2 Diabetes: A Meta-Analysis

Background: Thiazolidinediones (TZDs) are a type of oral drug that are utilized for the treatment of type 2 diabetes mellitus (T2DM). They function by acting as agonists for a nuclear transcription factor known as peroxisome proliferator-activated receptor-gamma (PPAR-γ). TZDs, such as pioglitazone and rosiglitazone, help enhance the regulation of metabolism in individuals with T2DM by improving their sensitivity to insulin. Previous studies have suggested a relationship between the therapeutic efficacy of TZDs and the PPARG Pro12Ala polymorphism (C > G, rs1801282). However, the small sample sizes of these studies may limit their applicability in clinical settings. To address this limitation, we conducted a meta-analysis assessing the influence of the PPARG Pro12Ala polymorphism on the responsiveness of TZDs. Method: We registered our study protocol with PROSPERO, number CRD42022354577. We conducted a comprehensive search of the PubMed, Web of Science, and Embase databases, including studies published up to August 2022. We examined studies investigating the association between the PPARG Pro12Ala polymorphism and metabolic parameters such as hemoglobin A_1C (HbA_1C), fasting plasma glucose (FPG), triglyceride (TG), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), and total cholesterol (TC). The mean difference (MD) and 95% confidence intervals (CIs) between pre- and post-drug administration were evaluated. The quality of the studies included in the meta-analysis was assessed by using the Newcastle-Ottawa Scale (NOS) tool for cohort studies. Heterogeneity across studies was assessed by using the I² value. An I² value greater than 50% indicated substantial heterogeneity, and a random-effects model was used for meta-analysis. If the I² value was below 50%, a fixed-effects model was employed instead. Both Begg's rank correlation test and Egger's regression test were performed to detect publication bias, using R Studio software. Results: Our meta-analysis incorporated 6 studies with 777 patients for blood glucose levels and 5 studies with 747 patients for lipid levels. The included studies were published between 2003 and 2016, with the majority involving Asian populations. Five of the six studies utilized pioglitazone, while the remaining study employed rosiglitazone. The quality scores, as assessed with the NOS, ranged from 8 to 9. Patients carrying the G allele exhibited a significantly greater reduction in HbA_1C (MD = -0.3; 95% CI = -0.55 to -0.05; p = 0.02) and FPG (MD = -10.91; 95% CI = -19.82 to -2.01; p = 0.02) levels compared to those with the CC genotype. Furthermore, individuals with the G allele experienced a significantly larger decrease in TG levels than those with the CC genotype (MD = -26.88; 95% CI = -41.30 to -12.46; p = 0.0003). No statistically significant differences were observed in LDL (MD = 6.69; 95% CI = -0.90 to 14.29; p = 0.08), HDL (MD = 0.31; 95% CI = -1.62 to 2.23; p = 0.75), and TC (MD = 6.4; 95% CI = -0.05 to 12.84; p = 0.05) levels. No evidence of publication bias was detected based on Begg's test and Egger's test results. Conclusions: This meta-analysis reveals that patients with the Ala12 variant in the PPARG Pro12Ala polymorphism are more likely to exhibit positive responses to TZD treatment in terms of HbA_1C, FPG, and TG levels compared to those with the Pro12/Pro12 genotype. These findings suggest that genotyping the PPARG Pro12Ala in diabetic patients may be advantageous for devising personalized treatment strategies, particularly for identifying individuals who are likely to respond favorably to TZDs.

The TMEM43 S358L mutation affects cardiac, small intestine, and metabolic homeostasis in a knock-in mouse model

The transmembrane protein 43 (TMEM43/LUMA) p.S358L mutation causes arrhythmogenic cardiomyopathy named as ARVC5, a fully penetrant disease with high risk of ventricular arrhythmias, sudden death, and heart failure. Male gender and vigorous exercise independently predicted deleterious outcome. Our systems genetics analysis revealed the importance of Tmem43 for cardiac and metabolic pathways associated with elevated lipid absorption from small intestine. This study sought to delineate gender-specific cardiac, intestinal, and metabolic phenotypes in vivo and investigate underlying pathophysiological mechanisms of S358L mutation. Serial echocardiography, surface electrocardiography (ECG), treadmill running, and body EchoMRI have been used in knock-in heterozygous (Tmem43WT/S358L), homozygous (Tmem43S358L), and wildtype (Tmem43WT) littermate mice. Electron microscopy, histology, immunohistochemistry, transcriptome, and protein analysis have been performed in cardiac and intestinal tissues. Systolic dysfunction was apparent in 3-mo-old Tmem43S358L and 6-mo-old Tmem43WT/S358L mutants. Both mutant lines displayed intolerance to acute stress at 6 mo of age, arrhythmias, fibro-fatty infiltration, and subcellular abnormalities in the myocardium. Microarray analysis found significantly differentially expressed genes between left ventricular (LV) and right ventricular (RV) myocardium. Mutants displayed diminished PPARG activities and significantly reduced TMEM43 and β-catenin expression in the heart, whereas junctional plakoglobin (JUP) translocated into nuclei of mutant cardiomyocytes. Conversely, elongated villi, fatty infiltration, and overexpression of gut epithelial proliferation markers, β-catenin and Ki-67, were evident in small intestine of mutants. We defined Tmem43 S358L-induced pathological effects on cardiac and intestinal homeostasis via distinctly disturbed WNT-β-catenin and PPARG signaling thereby contributing to ARVC5 pathophysiology. Results suggest that cardiometabolic assessment in mutation carriers may be important for predictive and personalized care.NEW & NOTEWORTHY This manuscript describes the findings of our investigation of cardiac, small intestine, and metabolic features of Tmem43-S358L mouse model. By investigating interorgan pathologies, we uncovered multiple mechanisms of the S358L-induced disease, and these unique mechanisms likely appear to contribute to the disease pathogenesis. We hope our findings are important and novel and open new avenues in the hunting for additional diagnostic and therapeutic targets in subjects carrying TMEM43 mutation.

Protective effects and mechanisms of Yi Qi Huo Xue Fang in cerebral ischemic stroke based on network pharmacology and experimental verification

ETHNOPHARMACOLOGICAL RELEVANCE

Yi Qi Huo Xue Fang (YQHXF) is an effective formula for treating cerebral ischemic stroke (CIS). However, its active ingredients and mechanism of action remain unclear.

AIM OF THE STUDY

This study aimed to reveal the mechanism of action of YQHXF in the treatment of ischemic stroke based on network pharmacology and experimental validation.

MATERIALS AND METHODS

This study identified the chemical components in YQHXF and the components absorbed by rat serum based on UPLC-Q-TOF/MS technology and used network pharmacology to predict key candidate targets. A protein-protein-interaction (P-P-I) network was constructed using String 11.0 database and Cytoscape, and R software for gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Finally, molecular docking combined with animal experiments was used to verify network pharmacology results.

RESULTS

This study identified and confirmed 36 chemical components of YQHXF and five chemical ingredients that were absorbed into the blood of rats and screened 66 key candidate targets. All targets in the P-P-I network were mainly related to inflammation and vascular processes. KEGG enrichment results revealed that these 66 key candidate targets were primarily involved in the "AGE-RAGE signaling pathway," "TNF-α signaling pathway, and "T cell receptor signaling pathway." Molecular docking results revealed that Prostaglandin-endoperoxidase synthase 2(PTGS-2), Nitric oxide synthase, endothelial (NOS3), and peroxisome proliferator-activated receptor gamma (PPARG) were more stably bound to their active ingredients. Animal experiments demonstrated that YQHXF promoted M2 polarization, inhibited M1 polarization in microglia, and promoted angiogenesis, which may be related to the PPARG pathway.

CONCLUSION

This study revealed the key active components and effective targets of YQHXF, identified the mechanism of action of YQHXF, laid the foundation for further research on YQHXF, and provided ideas for developing new drugs for CIS.

Association of the rs3856806 Polymorphism in the PPARG Gene with Type 2 Diabetes Mellitus: A Meta-Analysis of 11,811 Individuals

This study investigated the role of the rs3856806 single nucleotide variant (SNV) on the peroxisome proliferator-activated receptor γ with the development of type 2 diabetes mellitus (T2DM) by conducting a meta-analysis. Relevant studies were searched in PubMed and were selected according to the inclusion criteria. Data were extracted and subjected to analysis using Review Manager 5.4.1. Pooled odds ratios (OR) and 95% confidence intervals (CI) were computed to measure the association of the SNV with T2DM development. Nine studies published in English were retrieved up to October 1, 2021. Homogeneity (I2 = 3%, P = .41) was achieved for the allelic model with significant outcomes (OR: 0.82; 95% CI: 0.76-0.89; P < .00001). Genotypic models also yielded significant associations for the co-dominant, dominant, and recessive models. All genotypic analysis showed homogeneity (I2 = 0-31%, P = .17-0.76) of the pooled outcomes. Our findings suggest that carrying the T allele of the rs3856806 SNV significantly decreases the risk of acquiring T2DM. However, further studies are necessary to support our claims.

Discovery and characterization of orally bioavailable 4-chloro-6-fluoroisophthalamides as covalent PPARG inverse-agonists

PPAR gamma (PPARG) is a ligand activated transcription factor that regulates genes involved in inflammation, bone biology, lipid homeostasis, as well as a master regulator of adipogenesis and a potential lineage driver of luminal bladder cancer. While PPARG agonists lead to transcriptional activation of canonical target genes, inverse agonists have the opposite effect through inducing a transcriptionally repressive complex leading to repression of canonical target gene expression. While many agonists have been described and tested clinically, inverse agonists offer an underexplored avenue to modulate PPARG biology in vivo. Current inverse agonists lack favorable in vivo properties; herein we describe the discovery and characterization of a series of orally bioavailable 4-chloro-6-fluoroisophthalamides as covalent PPARG inverse-agonists, BAY-5516, BAY-5094, and BAY-9683. Structural studies of this series revealed distinct pre- and post-covalent binding positions, which led to the hypothesis that interactions in the pre-covalent conformation are primarily responsible for driving affinity, while interactions in the post-covalent conformation are more responsible for cellular functional effects by enhancing PPARG interactions with its corepressors. The need to simultaneously optimize for two distinct states may partially explain the steep SAR observed. Exquisite selectivity was achieved over related nuclear receptors in the subfamily due in part to a covalent warhead with low reactivity through an S_NAr mechanism in addition to the specificity gained through covalent binding to a reactive cysteine uniquely positioned within the PPARG LBD. BAY-5516, BAY-5094, and BAY-9683 lead to pharmacodynamic regulation of PPARG target gene expression in vivo comparable to known inverse agonist SR10221 and represent new tools for future in vivo studies to explore their potential utility for treatment of disorders of hyperactivated PPARG including luminal bladder cancer and other disorders.