PPARγ Protein Research Articles

Genomic and Bioinformatics Analysis of Familial Partial Lipodystrophy Type 3 Identified in a Patient with Novel PPARγ Mutation and Robust Response to Pioglitazone

Familial partial lipodystrophies (FPLDs) are very rare inherited disorders characterized by partial loss of adipose tissue from the upper and lower extremities. At least seven subtypes of FPLD have been identified and are mostly dominantly inherited. FPLD type 3 is caused by mutations in the PPARγ gene, which encodes for the protein peroxisome proliferator-activated receptor gamma (PPARγ). We identified a Saudi female with PFLD3 presented with partial lipoatrophy, uncontrolled diabetes, severe hypertriglyceridemia, and recurrent pancreatitis. The clinical and biochemical findings in this proband were described before and after treatment with Pioglitazone in addition to the conventional treatment. DNA extraction and whole exome sequencing (WES) were performed to detect the variant. The mutant gene was subjected to Sanger analysis to confirm the results. We applied five specific computational prediction tools to assess the pathogenicity of variation, namely the MT, DANN, CADD, BayesDel, and fitCons tools. We assessed protein modeling and stability with the AlphaFold-generated structures for both wild-type and mutant proteins. Finally, we conducted molecular docking using the AutoDock Vina virtual docking. Upon whole exome sequencing, a c.1024C>T p.(Gln342Ter) missense mutation was detected in the PPARγ gene associated with FPLD3. This variant is a novel mutation that has not been described in all genome databases. Sanger analysis confirmed the heterogenicity and pathogenicity of this variant. All five computational prediction tools indicate that this variant is considered highly pathogenic. Our patient showed a dramatic response to Pioglitazone, a synthetic PPARγ agonist. From structural modeling, we found that the enhanced binding affinity of the mutant PPARγ protein to Pioglitazone likely improves the activation of PPARγ, enhancing its transcriptional activity and resulting in better clinical outcomes. These findings extend the spectrum of PPARγ mutations responsible for FPLD3 and highlight the potential for personalized treatment strategies based on genetic mutations.

Cell-state dependent regulation of PPARγ signaling by the transcription factor ZBTB9 in adipocytes.

Peroxisome proliferator-activated receptor-γ (PPARγ) is a nuclear hormone receptor that is a master regulator of adipocyte differentiation and function. ZBTB9 is a widely expressed but poorly studied transcription factor that was predicted to interact with PPARγ based on large-scale protein-protein interaction experiments. In addition, genome-wide association studies (GWAS) revealed associations between ZBTB9 and BMI, T2D risk, and HbA1c levels. Here we show that Zbtb9 deficiency in mature adipocytes decreased PPARγ activity and protein level, and thus acts as a positive regulator of PPARγ signaling. In contrast, Zbtb9 deficiency in 3T3-L1 and human preadipocytes increased PPARγ levels and enhanced adipogenesis. Transcriptomic and transcription factor binding site analyses of Zbtb9 deficient preadipocytes revealed that the E2F pathway, controlled by the E2F family of transcription factors that are classically associated with cell cycle regulation, was among the most upregulated pathways. E2F1 positively regulates adipogenesis by promoting Pparg expression, independent of its cell cycle role, via direct binding to the Pparg promoter early during adipogenesis. RB phosphorylation (pRB), which regulates E2F activity, was also upregulated in Zbtb9 deficient preadipocytes. Critically, an E2F1 inhibitor blocked the effects of Zbtb9 deficiency on adipogenesis. Collectively, these results demonstrate that Zbtb9 inhibits adipogenesis as a negative regulator of Pparg expression via pRB-E2F signaling. Our findings reveal cell-state dependent roles of ZBTB9 in adipocytes, identifying a new molecule that regulates adipocyte biology as both a positive and negative regulator of PPARγ signaling depending on the cellular context, and thus may be important in the pathogenesis of obesity and T2D.

In-silico Study of Molecular Docking and Dynamics Simulations for N-Substituted Thiazolidinones Derived from (R)-Carvone Targeting PPAR-γ Protein: Synthesis and Characterization

In this article, we have selected the monoterpene (R)-carvone combined with thiazolidinone as scaffold. Moreover, this study details the synthesis, characterization, and theoretical analysis of novel (R)-Carvone-thiazolidinone-N-substituted derivatives, sourced from natural (R)-Carvone. The compounds were identified using HRMS, and 1H- and 13C-NMR spectral data. A theoretical analysis provided insights into the stability observed experimentally. The local electronic properties and topological features of two compounds 3 and d were studied using the Multiwfn tool and CrystalExplorer software. Specifically, the electron localization function, localized orbital locator and average local ionization energy were mapped to explore electron distribution, while interaction region indicator was used to analyze intermolecular interactions. An in silico docking study was conducted on the PPAR-γ protein to evaluate the binding affinity and interactions. Furthermore, a 200 ns molecular dynamics simulation was performed to confirm the stability of the compounds within the PPAR-γ protein’s binding site. The results indicated consistent stability for all three compounds under dynamic conditions. Lastly, in silico evaluations of drug-likeness and toxicity prediction showed that all compounds adhere to the criteria of both Lipinski’s Rule of Five and Jorgensen’s Rule of Three, confirming their potential as drug candidates.

Mechanism of Mettl14 regulating AIM2 inflammasome activation and neuronal apoptosis and pyroptosis in spinal cord injury by mediating PPARγ m6A methylation.

Spinal cord injury (SCI) represents a destructive pathological and neurological state. Methyltransferase-like 14 (Mettl14)-mediated m6A modification links to spinal cord injury (SCI), and we explored its mechanism. SCI mouse models were subjected to si-Mettl14 and si-negative control treatments and mouse behavior, pathological condition and apoptosis assessments. The oxygen/glucose deprivation (OGD)-induced spinal cord neuronal cell models were processed with si-Mettl14 and si-peroxisome proliferator-activated receptor γ (PPARγ) plasmids, and pcDNA3.1-YTHDF2 or synthetic dsDNA Poly(dA: dT), followed by viability and apoptosis evaluation by MTT and flow cytometry. Levels of Mettl14, PPARγ, and YTHDF2 mRNAs and proteins, AIM2 inflammasome activation-associated and pyroptosis marker proteins, PPARγ m6A methylation and pyroptosis-related inflammatory factors were determined by RT-qPCR, Western blot, Me-RIP and ELISA, with PPARγ mRNA stability and YTHDF2-PPARγ interaction assessed. Mettl14 and PPARγ m6A modification levels rose in SCI spinal cord tissues, while PPARγ levels dropped. Mettl14 knockdown dampened m6A modification, up-regulated PPARγ levels, weakened neuronal apoptosis, and ameliorated SCI in mice. OGD down-regulated PPARγ and accelerated OGD-induced neuronal apoptosis and pyroptosis via inducing Mettl14-mediated m6A modification. Mettl14 amplified PPARγ mRNA degradation and down-regulated PPARγ by mediating m6A methylation via the YTHDF2-dependent pathway. Mettl14 silencing-mediated PPARγ m6A methylation mitigated OGD-induced neuronal apoptosis and pyroptosis by inactivating AIM2 inflammasome. Mettl14 triggered activated AIM2 inflammasomes, promoted neuronal apoptosis and pyroptosis, and worsened SCI in SCI mice via mediating PPARγ m6A methylation. Mettl14 regulates AIM2 inflammasome activation, and redounds to spinal cord neuronal apoptosis and pyroptosis in SCI by mediating m6A methylation of PPARγ.

Rifaximin alleviates MCD diet-induced NASH in mice by restoring the gut microbiota and intestinal barrier

AimsDue to the increasing global incidence rate of nonalcoholic steatohepatitis (NASH) combined with the lack of effective treatment methods for this disease, there is an urgent need to find new treatment strategies. The aim of this study was to investigate the efficacy of rifaximin in preventing and treating NASH and the related mechanism. Materials and methodsA NASH model was constructed by feeding male C57BL/6 mice a methionine-choline-deficient (MCD) diet for 4 weeks. Rifaximin was administered for 1 week before MCD diet feeding or during the last week of MCD diet feeding to investigate its preventive or therapeutic effects. Liver pathology, hepatic enzyme levels and metabolic indices were measured to evaluate the effects of rifaximin on NASH. Intestinal barrier integrity was measured via the Ussing chamber system and western blotting. 16S rDNA sequencing was conducted to investigate the fecal microbiota composition. Western blotting was performed to evaluate peroxisome proliferator activated receptor (PPAR)α and PPARγ protein levels. Key findingsRifaximin effectively alleviated MCD diet-induced NASH. The microbiota composition in MCD diet-fed mice was significantly altered, and intestinal barrier integrity was disrupted. Dysbiosis and intestinal barrier dysfunction were reversed by rifaximin. In addition, rifaximin modulated PPARα and PPARγ expression in the liver. SignificanceRifaximin effectively alleviated MCD diet-induced NASH by restoring the gut microbiota and reversing intestinal barrier dysfunction, suggesting that rifaximin treatment is a new approach for preventing and treating NASH.

Determination of adipogenesis stages of human umbilical cord-derived mesenchymal stem cells using three-dimensional label-free holotomography

Adipogenesis involves complex changes in gene expression, morphology, and cytoskeletal organization. However, the quantitative analysis of live cell images to identify their stages through morphological markers is limited. Distinct adipogenesis markers on human umbilical cord-derived mesenchymal stem cells (UC-MSCs) were identified through holotomography, a label-free live cell imaging technique. In the MSC-to-preadipocyte transition, the nucleus-to-cytoplasm ratio (0.080 vs. 0.052) and lipid droplet (LD) refractive index variation decreased (0.149 % vs. 0.061 %), whereas the LD number (20 vs. 65) increased. This event was also accompanied by the downregulation and upregulation of THY1 and Preadipocyte Factor-1 (PREF-1), respectively. In the preadipocyte to immature adipocyte shift, cell sphericity (0.20 vs. 0.43) and LD number (65 vs. 200) surged, large LDs (>10 μm3) appeared, and the major axis of the cell was reduced (143.7 μm vs. 83.12 μm). These findings indicate features of preadipocyte and immature adipocyte stages, alongside the downregulation of PREF-1 and upregulation of Peroxisome Proliferator-Activated Receptor gamma (PPARγ). In adipocyte maturation, along with PPARγ and Fatty Acid-Binding Protein 4 upregulation, cell compactness (0.15 vs. 0.29) and sphericity (0.43 vs. 0.59) increased, and larger LDs (>30 μm3) formed, marking immature and mature adipocyte stages. The study highlights the distinct adipogenic morphological biomarkers of adipogenesis stages in UC-MSCs, providing potential applications in biomedical and clinical settings, such as fostering innovative medical strategies for treating metabolic disease.

SUN1 inhibits osteogenesis and promotes adipogenesis of human adipose-derived stem cells by regulating α-tubulin and CD36 expression.

Sad and UNC84 domain 1 (SUN1) is a kind of nuclear envelope protein with established involvement in cellular processes, including nuclear motility and meiosis. SUN1 plays an intriguing role in human adipose-derived stem cells (hASCs) differentiation; however, this role remains largely undefined. This study was undertaken to investigate the role of SUN1 in hASCs differentiation, as well as its underlying mechanisms. Employing siRNAs, we selectively downregulated SUN1 and CD36 expression. Microtubules were depolymerized using nocodazole, and PPARγ was activated using rosiglitazone. Western blotting was performed to quantify SUN1, PPARγ, α-tubulin, CD36, OPN, and adiponectin protein expression levels. Alkaline phosphatase and Oil red O staining were used to assess osteogenesis and adipogenesis, respectively. Downregulated SUN1 expression increased osteogenesis and decreased adipogenesis in hASCs, concomitant with upregulated α-tubulin expression and downregulated CD36 expression, alongside reduced nuclear localization of PPARγ. Microtubule depolymerization increased CD36 expression. Rescue experiments indicated that microtubule depolymerization counteracted the downregulated SUN1-induced phenotypic changes. This study demonstrates that SUN1 influences the differentiation of hASCs towards osteogenic and adipogenic lineages, indicating its essential role in cell fate.

Dual anti-inflammatory effects of curcumin and berberine on acetaminophen-induced liver injury in mice by inhibiting NF-κB activation via PI3K/AKT and PPARγ signaling pathways

Acetaminophen (APAP) overdose is still a leading cause of drug-induced liver injury (DILI), accompanied with severe inflammatory response. However, the therapy for APAP-induced DILI is rather limited. The combined application of natural products to treat DILI induced by APAP may be a new direction of the research. This study was conducted to evaluate the dual anti-inflammatory activity of curcumin (CUR) combined with berberine (BBR) against APAP-mediated DILI. Network pharmacology found that PI3K-Akt and PPAR signaling pathways were primarily involved in anti-DILI of the combination of CUR and BBR. APAP injection enhanced the levels of ALT, AST, IL-1β, IL-6, and TNF-α in mice, while such phenomenon was significantly reversed by the cotreatment of CUR and BBR, which was more effective than either single treatment. The increase of p-NF-κB and p-IKKα/β protein expression and the decrease of p-PI3K, p-AKT, and PPARγ protein expression in APAP-treated mice were markedly inhibited by the coadministration of CUR and BBR. Molecular docking further demonstrated that both CUR and BBR could stably bind to PI3K, AKT, and PPARγ protein. In conclusion, the combination of CUR and BBR more effectively protected liver from APAP-triggered DILI than individual treatment. The mechanism is to alleviate hepatic inflammation by inhibiting NF-κB activation, which is possibly mediated by PI3K/Akt and PPARγ signaling pathways.

Yanghe Decoction promotes ferroptosis through PPARγ-dependent autophagy to inhibit the malignant progression of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a heterogeneous subtype of breast cancer that displays highly aggressive with poor prognosis. Yanghe Decoction (YHD) has been used in the treatment of breast cancer for many years. We aimed to explore the effects of YHD on the malignant phenotypes of MDA-MB-231 cells and the potential mechanism related to PPARγ, autophagy and ferroptosis. The serum of rat containing different concentrations of YHD were collected to culture MDA-MB-231 cells. Cell viability and proliferation were assessed by the CCK-8 assay and EDU staining. Wound healing- and transwell assays were used to detect the capacities of MDA-MB-231 cell migration and invasion. Additionally, the levels of lipid peroxidation, Fe2+ and the expression of ferroptosis-related proteins were evaluated. The expression of PPARγ and autophagy-related proteins was assessed using immunofluorescence staining or western blot assay. Then, the PPARγ inhibitor (GW9662), autophagy inhibitor (3-MA) and autophagy inducer (rapamycin; Rap) were used to further study the potential mechanism of YHD on TNBC. Results indicated that contained-YHD serum significantly decreased the viability, proliferation, migration and invasion of TNBC cells. Moreover, YHD promoted lipid peroxidation level, elevated Fe2+ content and downregulated GPX4, SLC7A11 and SLC3A2 expression. Besides, autophagy was induced and PPARγ was upregulated by YHD in MDA-MB-231 cells. Furthermore, GW9662 alleviated the impacts of YHD on autophagy of MDA-MB-231 cells. Rap reversed the effects of GW9662 on lipid peroxidation, ferroptosis, proliferation, migration and invasion of MDA-MB-231 cells. 3-MA had the similar effects to GW9662. Collectively, YHD suppressed the malignant progression of MDA-MB-231 cells by inducing ferroptosis through PPARγ-dependent autophagy.

Turkish coffee has an antitumor effect on breast cancer cells in vitro and in vivo

BackgroundBreast cancer is the most diagnosed cancer in women. Its pathogenesis includes several pathways in cancer proliferation, apoptosis, and metastasis. Some clinical data have indicated the association between coffee consumption and decreased cancer risk. However, little data is available on the effect of coffee on breast cancer cells in vitro and in vivo.MethodsIn our study, we assessed the effect of Turkish coffee and Fridamycin-H on different pathways in breast cancer, including apoptosis, proliferation, and oxidative stress. A human breast cancer cell line (MCF-7) was treated for 48 h with either coffee extract (5% or 10 v/v) or Fridamycin-H (10 ng/ml). Ehrlich solid tumors were induced in mice for in vivo modeling of breast cancer. Mice with Ehrlich solid tumors were treated orally with coffee extract in drinking water at a final concentration (v/v) of either 3%, 5%, or 10% daily for 21 days. Protein expression levels of Caspase-8 were determined in both in vitro and in vivo models using ELISA assay. Moreover, P-glycoprotein and peroxisome proliferator-activated receptor gamma (PPAR-γ) protein expression levels were analyzed in the in vitro model. β-catenin protein expression was analyzed in tumor sections using immunohistochemical analysis. In addition, malondialdehyde (MDA) serum levels were analyzed using colorimetry.ResultsBoth coffee extract and Fridamycin-H significantly increased Caspase-8, P-glycoprotein, and PPAR-γ protein levels in MCF-7 cells. Consistently, all doses of in vivo coffee treatment induced a significant increase in Caspase-8 and necrotic zones and a significant decrease in β- catenin, MDA, tumor volume, tumor weight, and viable tumor cell density.ConclusionThese findings suggest that coffee extract and Fridamycin-H warrant further exploration as potential therapies for breast cancer.

Seabuckthorn polysaccharides mitigate hepatic steatosis by modulating the Nrf-2/HO-1 pathway and gut microbiota

Non-alcoholic fatty liver disease (NAFLD) is becoming a significant global public health threat. Seabuckthorn (Hippophae rhamnoides L.) has been used in traditional Chinese medicine (TCM). The hypolipidemic effects of Seabuckthorn polysaccharides (SP) against high-fat diets (HFD)-induced NAFLD were systematically explored and compared with that of Bifidobacterium lactis V9 (B. Lactis V9). Results showed that HFD-induced alanine transaminase (ALT) and aspartate aminotransferase (AST) levels decreased by 2.8-fold and 4.5-fold, respectively, after SP supplementation. Moreover, the alleviating effect on hepatic lipid accumulation is better than that of B. Lactis V9. The ACC and FASN mRNA levels were significantly reduced by 1.8 fold (P < 0.05) and 2.3 folds (P < 0.05), respectively, while the CPT1α and PPARα mRNA levels was significantly increased by 2.3 fold (P < 0.05) and 1.6 fold (P < 0.05), respectively, after SP administration. SP activated phosphorylated-AMPK and inhibited PPARγ protein expression, improved serum oxidative stress and inflammation (P < 0.05). SP supplementation leads to increased hepatic expression of nuclear factor erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1) and Superoxide dismutase-2 (SOD-2). Furthermore, SP treatment improved HFD-induced intestinal dysbiosis. Lentisphaerae, Firmicutes, Tenericutes and Peptococcus sp., RC9_gut_group sp., and Parabacteroides sp. of the gut microbiota were significantly associated with hepatic steatosis and indicators related to oxidative stress and inflammation. Therefore, SP can mitigate hepatic lipid accumulation by regulating Nrf-2/HO-1 signaling pathways and gut microbiota. This study offers new evidence supporting the use of SP as a prebiotic treatment for NAFLD.

Uncovering the mechanisms of diosmin in treating obesity-related kidney injury based on network pharmacology, molecular docking, and in vitro validation.

Obesity increases the risk of kidney injury, involving various pathological events such as inflammation, insulin resistance, lipid metabolism disorders, and hemodynamic changes, making it a significant risk factor for the development and progression of chronic kidney disease. Diosmin, a natural flavonoid glycoside, exhibits anti-inflammatory, antioxidant, anti-lipid, and vasodilatory effects. However, whether diosmin has a protective effect on obesity-related kidney injury remains unclear. The molecular formula of diosmin was obtained, and diosmin and target genes related to obesity-related kidney injury were screened. The interaction between overlapping target genes was analyzed. GO functional enrichment and KEGG pathway enrichment analyses were performed on overlapping target genes. Molecular docking was employed to assess the binding strength between overlapping target genes. Palmitic acid-induced damage to HK-2 cells, which were then treated with diosmin. Subsequently, the expression levels of relevant mRNAs and proteins were measured. Network analysis identified 219 potential diosmin target genes, 6800 potential target genes related to obesity-related kidney injury, and 93 potential overlapping target genes. Protein-protein interaction networks and molecular docking results revealed that AKT1, TNF-α, SRC, EGFR, ESR1, CASP3, MMP9, PPAR-γ, GSK-3β, and MMP2 were identified as key therapeutic targets, and they exhibited stable binding with diosmin. GO analysis indicated that these key targets may participate in inflammation, chemical stress, and protein phosphorylation. KEGG revealed that pathways in cancer, AGE-RAGE signaling pathway, PI3K-AKT signaling pathway, PPAR signaling pathway, and insulin resistance as crucial in treating obesity-related kidney injury. CCK-8 assay showed that diosmin significantly restored the viability of HK-2 cells affected by palmitic acid. Oil Red O staining demonstrated that diosmin significantly improved lipid deposition in HK-2 cells induced by palmitic acid. PCR results showed that diosmin inhibited the mRNA levels of AKT1, TNF-α, EGFR, ESR1, CASP3, MMP9, GSK-3β, and MMP2 while promoting the mRNA level of PPAR-γ. Western blot analysis revealed that diosmin restored PPAR-γ protein expression, inhibited NF-kB p-p65 protein expression, and reduced TNF-α protein expression. Diosmin demonstrated multi-target and multi-pathway effects in the treatment of obesity-associated renal injury, with key targets including AKT1, TNF-α, EGFR, ESR1, CASP3, MMP9, PPAR-γ, GSK-3β, and MMP2. The mechanism may be through the modulation of the PPAR-γ/NF-κB signaling pathway, which can attenuate inflammatory responses and protect the kidney.

Bis-chalcones obtained via one-pot synthesis as the anti-neurodegenerative agents and their effect on the HT-22 cell line

In the area of research on neurodegenerative diseases, the current challenge is to search for appropriate research methods that would detect these diseases at the earliest possible stage, but also new active structures that would reduce the rate of the disease progression and minimize the intensity of their symptoms experienced by the patient. The chalcones are considered in the context of candidates for new drugs dedicated to the fight against neurodegenerative diseases. The synthesis of bis-chalcone derivatives (3a-3d), as aim molecules was performed. Their structures were established by applying 1H NMR, 13C NMR, MS, FT-IR and UV–Vis spectra. All bis-chalcones were synthesized from terephthalaldehyde and appropriate aromatic ketone as substrates in the Claisen-Schmidt condensation method and evaluated in the biological tests and in silico analysis. Compounds exerted antioxidant activity using the HORAC method (3a-3d) and decreased the activities of GPx, COX-2 (3b-3d), GR (3a-3c) and CAT (3a,3b). The high anti-neurodegenerative potential of all four bis-chalcones was observed by inhibition of acetyl- (AChE) and butyrylcholinesterase (BChE) and a positive effect on the mouse hippocampal neuronal HT-22 cell line (LDH release and PGC-1α, PPARγ and GAPDH protein expression). TD-DFT method (computing a number of descriptors associated with HOMO–LUMO electron transition: electronegativity, chemical hardness and potential, first ionization potential, electron affinity) was employed to study the spectroscopic properties. This method showed that the first excited state of compounds was consistent with their maximum absorption in the computed UV–Vis spectra, which showed good agreement with the experimental spectrum using PBE1PBE functional. Using in silico approach, interactions of bis-chalcones with selected targets (aryl hydrocarbon receptor (AhR) PAS-A Domain, ligand binding domain of human PPAR-γ, soman-aged human BChE-butyrylthiocholine complex, Torpedo californica AChE:N-piperidinopropyl-galanthamine complex and the COX-2-celecoxib complex) were characterized. Results obtained in in silico models were consistent with in vitro experiments.

Molecular docking of ferulic acid, bakuchiol and niazirin on peroxisome proliferator-activated receptor gamma (PPAR-γ) as anti-diabetic agents

Background: Diabetes mellitus remains one of the most dangerous illnesses worldwide. The PPAR-gamma protein plays a crucial role in lipid and carbohydrate metabolism, making it a key target for diabetes therapy. Research into plant-derived active compounds for diabetes treatment is increasingly important. Objective: This study aims to evaluate and analyze the interaction of ferulic acid, niazirin, and bakuchiol with the peroxisome proliferator-activated receptor gamma (PPAR-γ) protein using molecular docking. Methods: Molecular docking was employed to assess the interactions between ferulic acid, niazirin, bakuchiol, and the PPAR-γ protein (PDB ID: 2PRG). The analysis focused on binding free energy values, amino acid residue interactions, the number of hydrogen bonds, and bond distances, comparing these results to those of the native ligand and pioglitazone, a known anti-diabetic drug targeting PPAR-γ. Results: The binding free energies for the ferulic acid-PPAR-γ, bakuchiol-PPAR-γ, niazirin-PPAR-γ, native ligand-PPAR-γ, and pioglitazone-PPAR-γ complexes were -5.54 kcal/mol, -8.47 kcal/mol, -6.56 kcal/mol, -10.08 kcal/mol, and -9.94 kcal/mol, respectively. The amino acid residue similarity percentages with the native ligand were 18.18% for ferulic acid, 27.27% for bakuchiol, 18.18% for niazirin, and 81.82% for pioglitazone. The native ligand-2PRG and pioglitazone-2PRG complexes exhibited superior hydrogen bond numbers and shorter bond distances compared to the other compounds. Conclusion: Although bakuchiol showed the most promising interaction among the tested compounds, none surpassed the binding affinity and stability of the native ligand or pioglitazone. Further research is needed to optimize these compounds for potential anti-diabetic therapy.

The Lian-Dou-Qing-Mai Formula activates the PPARγ-LXRα-ABCA1/ABCG1 pathway by regulating IL-10, leading to the promotion of cholesterol efflux and a reduction in atherosclerotic plaques.

To observe the effect of the Lian-Dou-Qing-Mai (LDQM) formula on lipid metabolism in mice and explore its mechanism from the perspective of regulating the PPARγ/LXRα/ABCA1 signaling pathway. THP-1 cells were induced to transform into foam cells with ox-LDL. Atherosclerosis (AS) models were constructed using a high-fat diet in ApoE-/- mice. Detection kits were used to evaluate triglyceride (TG) and total cholesterol (TC) content; TNF-α, MCP-1, MMP-9, TMP-1, PPARγ, LXRα, ABCA1, and ABCG1 mRNA and protein expression were identified using real-time PCR and western blot. Interleukin-10 (IL-10) blood levels were measured using an enzyme-linked immunosorbent assay (ELISA), and aortic plaque development and lipid deposition were seen using hematoxylin and eosin (HE) and oil red O staining, respectively. In the cell model, LDQM could inhibit the formation of THP-1 macrophage-derived foam cells and the expression of inflammatory factors, promote macrophage cholesterol efflux, increase the expression of IL-10, and activate the PPARγ-LXRα-ABCA1/ABCG1 pathway. Additional IL-10 treatment further promotes LDQM-induced cholesterol efflux in THP-1 cells; in In vivo models, LDQM inhibited the area of atherosclerotic lesions, aortic lipid deposition, and inflammation levels in ApoE-/- mice through IL-10, and activated the expression level of the PPARγ-LXRα-ABCA1/ABCG1 pathway. LDQM may affect the PPARγ/LXRα/ABCA1 signaling pathway through IL-10, regulate lipid metabolism, reduce serum inflammatory expression and lipid deposition, and improve the formation of atheroplaques.

Green Tea Polyphenol (-)-Epicatechin Pretreatment Mitigates Hepatic Steatosis in an In Vitro MASLD Model.

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is becoming more prominent globally due to an increase in the prevalence of obesity, dyslipidemia, and type 2 diabetes. A great deal of studies have proposed potential treatments for MASLD, with few of them demonstrating promising results. The aim of this study was to investigate the potential effects of (-)-epicatechin (EPI) on the development of MASLD in an in vitro model using the HepG2 cell line by determining the metabolic viability of the cells and the levels of PPARα, PPARγ, and GSH. HepG2 cells were pretreated with 10, 30, 50, and 100 μM EPI for 4 h to assess the potential effects of EPI on lipid metabolism. A MASLD cell culture model was established using HepG2 hepatocytes which were exposed to 1.5 mM oleic acid (OA) for 24 h. Moreover, colorimetric MTS assay was used in order to determine the metabolic viability of the cells, PPARα and PPARγ protein levels were determined using enzyme-linked immunosorbent assay (ELISA), and lipid accumulation was visualized using the Oil Red O Staining method. Also, the levels of intracellular glutathione (GSH) were measured to determine the level of oxidative stress. EPI was shown to increase the metabolic viability of the cells treated with OA. The metabolic viability of HepG2 cells, after 24 h incubation with OA, was significantly decreased, with a metabolic viability of 71%, compared to the cells pretreated with EPI, where the metabolic viability was 74-86% with respect to the concentration of EPI used in the experiment. Furthermore, the levels of PPARα, PPARγ, and GSH exhibited a decrease in response to increasing EPI concentrations. Pretreatment with EPI has demonstrated a great effect on the levels of PPARα, PPARγ, and GSH in vitro. Therefore, considering that EPI mediates lipid metabolism in MASLD, it should be considered a promising hepatoprotective agent in future research.

Palmitoyltransferase ZDHHC6 promotes colon tumorigenesis by targeting PPARγ-driven lipid biosynthesis via regulating lipidome metabolic reprogramming

BackgroundThe failure of proper recognition of the intricate nature of pathophysiology in colorectal cancer (CRC) has a substantial effect on the progress of developing novel medications and targeted therapy approaches. Imbalances in the processes of lipid oxidation and biosynthesis of fatty acids are significant risk factors for the development of CRC. Therapeutic intervention that specifically targets the peroxisome proliferator-activated receptor gamma (PPARγ) and its downstream response element, in response to lipid metabolism, has been found to promote the growth of tumors and has shown significant clinical advantages in cancer patients.MethodsClinical CRC samples and extensive in vitro and in vivo experiments were carried out to determine the role of ZDHHC6 and its downstream targets via a series of biochemical assays, molecular analysis approaches and lipid metabolomics assay, etc.ResultsTo study the effect of ZDHHC6 on the progression of CRC and identify whether ZDHHC6 is a palmitoyltransferase that regulates fatty acid synthesis, which directly palmitoylates and stabilizes PPARγ, and this stabilization in turn activates the ACLY transcription-related metabolic pathway. In this study, we demonstrate that PPARγ undergoes palmitoylation in its DNA binding domain (DBD) section. This lipid-related modification enhances the stability of PPARγ protein by preventing its destabilization. As a result, palmitoylated PPARγ inhibits its degradation induced by the lysosome and facilitates its translocation into the nucleus. In addition, we have identified zinc finger-aspartate-histidine-cysteine 6 (ZDHHC6) as a crucial controller of fatty acid biosynthesis. ZDHHC6 directly interacts with and adds palmitoyl groups to stabilize PPARγ at the Cys-313 site within the DBD domain of PPARγ. Consequently, this palmitoylation leads to an increase in the expression of ATP citrate lyase (ACLY). Furthermore, our findings reveals that ZDHHC6 actively stimulates the production of fatty acids and plays a role in the development of colorectal cancer. However, we have observed a significant reduction in the cancer-causing effects when the expression of ZDHHC6 is inhibited in in vivo trials. Significantly, in CRC, there is a strong positive correlation between the high expression of ZDHHC6 and the expression of PPARγ. Moreover, this high expression of ZDHHC6 is connected with the severity of CRC and is indicative of a poor prognosis.ConclusionsWe have discovered a mechanism in which lipid biosynthesis is controlled by ZDHHC6 and includes the signaling of PPARγ-ACLY in the advancement of CRC. This finding provides a justification for targeting lipid synthesis by blocking ZDHHC6 as a potential therapeutic approach.

Anti-tumor effect of zartoprofen, a non-steroidal anti-inflammatory drug, targeting PPARγ (peroxisome proliferator-activated receptor gamma) on chondrosarcoma.

232 Background: Peroxisome proliferator-activated receptor gamma (PPARγ) plays a central role in the differentiation of adipocytes. Anti-tumor effects by activating PPARγ have been reported on chondrosarcoma. We revealed that zaltoprofen, a non-steroidal anti-inflammatory drug (NSAID), could activate and induce PPARγ in chondrosarcoma cells. We report antitumor effects of zaltoprofen targeting PPARγ on chondrosarcoma. Methods: PPARγ activation by zaltoprofen was assessed with luciferase assay. Human chondrosarcoma cells and PPARγ-silencing cells established with shRNA were subjected to the anti-tumor analyses, western blotting, RT-PCR, and zymography. For in vivo study, chondrosarcoma cells were subcutaneously inoculated into nude mice. Zaltoprofen was administered to mice (30 mg/kg/day). Tumors were pathologically assessed. We obtained tumor tissue specimens from a patient who underwent several surgeries for recurrent spinal chondrosarcoma. The patient was administered zaltoprofen as a therapeutic agent for algia the tumor remained stable for more than 2 years. Pathological analyses were performed on the specimen before and after administration of zaltoprofen). Results: Zaltoprofen significantly increased PPARg activation (EC50 47.3 uM). Treatment with 200–400 uM zaltoprofen significantly inhibited cell viability and induced PPARγ protein and mRNA expression in chondrosarcoma cells. Zaltoprofen (400 uM) significantly decreased the cell proliferation, migration, invasion, and MMP2 expression in control cells, whereas these were significantly increased in PPARγ-silencing cells. Also, zaltoprofen (400 uM) induced p21, p27, and p53 expression in control cells, whereas these effects were canceled in PPARg-silencing cells. Upregulation of KROX20 followed by CEBP-α and –β, all of which were reported to induce PPARγ in normal adipose tissue, were detected after zaltoprofen administration. Tumor growth was significantly inhibited in mice administered zaltoprofen. Apoptotic indices in the TUNEL-labeled area were significantly larger and Ki-67 positive cells were significantly lower in tumor specimens from mice administered zaltoprofen. Patient’s specimens revealed that PPARγ expression was stronger and MMP2 expression was weaker in post-administration specimens. Conclusions: Zaltoprofen suppressed tumor progression by inhibiting cell proliferation, migration, and invasion with induction of PPARγ expression in chondrosarcoma cells. The suppressing effect on tumor progression by zaltoprofen was also observed in vivo. Zaltoprofen induced PPARγ expression and MMP2 downregulation in clinical specimens with expected antitumor effects. This is the first study demonstrating that one of the NSAIDs, zaltoprofen, may act as an antitumor agent by targeting PPARγ for chondrosarcoma.

Elastin-derived peptides (EDPs) affect gene and protein expression in human mesenchymal stem cells (hMSCs) – preliminary study

During the aging process, elastin is degraded and the level of elastin-derived peptides (EDPs) successively increases. The main peptide released from elastin during its degradation is a peptide with the VGVAPG sequence. To date, several papers have described that EDPs or elastin-like peptides (ELPs) affect human mesenchymal stem cells (hMSCs) derived from different tissues. Unfortunately, despite the described effect of EDPs or ELPs on the hMSC differentiation process, the mechanism of action of these peptides has not been elucidated. Therefore, the aim of the present study was to evaluate the impact of the VGVAPG and VVGPGA peptides on the hMSC stemness marker and elucidation of the mechanism of action of these peptides. Our data show that both studied peptides (VGVAPG and VVGPGA) act with the involvement of ERK1/2 and c-SRC kinases. However, their mechanism of activation is probably different in hMSCs derived from adipose tissue. Both studied peptides increase the KI67 protein level in hMSCs, but this is not accompanied with cell proliferation. Moreover, the changes in the NANOG and c-MYC protein expression and in the SOX2 and POU5F1 mRNA expression suggest that EDPs reduced the hMSC stemness properties and could initiate cell differentiation. The initiation of differentiation was evidenced by changes in the expression of AhR and PPARγ protein as well as specific genes (ACTB, TUBB3) and proteins (β-actin, RhoA) involved in cytoskeleton remodeling. Our data suggest that the presence of EDPs in tissue can initiate hMSC differentiation into more tissue-specific cells.

Inhibitory Activity of Sparassis latifolia on the Lipid Accumulation through Suppressing Adipogenesis and Activating Lipolysis in 3T3-L1 Cells.

Sparassis latifolia (SL) has been reported to exhibit anti-obesity effects in high-fat diet animal models, yet research into its mechanisms of action remains limited. Therefore, this study aimed to elucidate the mechanisms behind the anti-obesity activity of SL's 30% ethanol extract (SL30E) using 3T3-L1 cells in an in vitro setting. SL30E effectively mitigated the accumulation of lipid droplets and triacylglycerol. SL30E downregulated PPARγ and CEBPα protein levels. The diminishment of PPARγ and C/EBPα, facilitated by SL30E, was impeded by the knockdown of β-catenin using β-cateninspecific siRNA. Furthermore, SL30E was observed to increase the protein levels of ATGL and p-HSL, while it concurrently decreased the protein levels of perilipin-1. SL30E downregulated p62/SQSTM1 protein level and upregulated LC3-II protein level. Moreover, SL30E was demonstrated to elevate the protein levels of p-AMPK and PGC-1α. The results indicate that SL30E inhibits lipid accumulation by suppressing adipogenesis and inducing lipolysis, lipophagy, and thermogenesis in 3T3-L1 cells. These observations provide potential insights into the mechanisms underlying the anti-obesity effects of SL, contributing valuable information to the existing body of knowledge.