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International Journal of Molecular... May 2024A robust predictive model was developed using 136 novel peroxisome proliferator-activated receptor delta (PPARδ) agonists, a distinct subtype of lipid-activated...
A robust predictive model was developed using 136 novel peroxisome proliferator-activated receptor delta (PPARδ) agonists, a distinct subtype of lipid-activated transcription factors of the nuclear receptor superfamily that regulate target genes by binding to characteristic sequences of DNA bases. The model employs various structural descriptors and docking calculations and provides predictions of the biological activity of PPARδ agonists, following the criteria of the Organization for Economic Co-operation and Development (OECD) for the development and validation of quantitative structure-activity relationship (QSAR) models. Specifically focused on small molecules, the model facilitates the identification of highly potent and selective PPARδ agonists and offers a read-across concept by providing the chemical neighbours of the compound under study. The model development process was conducted on Isalos Analytics Software (v. 0.1.17) which provides an intuitive environment for machine-learning applications. The final model was released as a user-friendly web tool and can be accessed through the Enalos Cloud platform's graphical user interface (GUI).
Topics: Quantitative Structure-Activity Relationship; PPAR delta; Software; Molecular Docking Simulation; Humans; Machine Learning
PubMed: 38791255
DOI: 10.3390/ijms25105216 -
Molecular Metabolism May 2024The prevalence of metabolic diseases is increasing globally at an alarming rate; thus, it is essential that effective, accessible, low-cost therapeutics are developed....
OBJECTIVE
The prevalence of metabolic diseases is increasing globally at an alarming rate; thus, it is essential that effective, accessible, low-cost therapeutics are developed. Peroxisome proliferator-activated receptors (PPARs) are transcription factors that tightly regulate glucose homeostasis and lipid metabolism and are important drug targets for the treatment of type 2 diabetes and dyslipidemia. We previously identified LDT409, a fatty acid-like compound derived from cashew nut shell liquid, as a novel pan-active PPARα/γ/δ compound. Herein, we aimed to assess the efficacy of LDT409 in vivo and investigate the molecular mechanisms governing the actions of the fatty acid mimetic LDT409 in diet-induced obese mice.
METHODS
C57Bl/6 mice (6-11-month-old) were fed a chow or high fat diet (HFD) for 4 weeks; mice thereafter received once daily intraperitoneal injections of vehicle, 10 mg/kg Rosiglitazone, 40 mg/kg WY14643, or 40 mg/kg LDT409 for 18 days while continuing the HFD. During treatments, body weight, food intake, glucose and insulin tolerance, energy expenditure, and intestinal lipid absorption were measured. On day 18 of treatment, tissues and plasma were collected for histological, molecular, and biochemical analysis.
RESULTS
We found that treatment with LDT409 was effective at reversing HFD-induced obesity and associated metabolic abnormalities in mice. LDT409 lowered food intake and hyperlipidemia, while improving insulin tolerance. Despite being a substrate of both PPARα and PPARγ, LDT409 was crucial for promoting hepatic fatty acid oxidation and reducing hepatic steatosis in HFD-fed mice. We also highlighted a role for LDT409 in white and brown adipocytes in vitro and in vivo where it decreased fat accumulation, increased lipolysis, induced browning of WAT, and upregulated thermogenic gene Ucp1. Remarkably, LDT409 reversed HFD-induced weight gain back to chow-fed control levels. We determined that the LDT409-induced weight-loss was associated with a combination of increased energy expenditure (detectable before weight loss was apparent), decreased food intake, increased systemic fat utilization, and increased fecal lipid excretion in HFD-fed mice.
CONCLUSIONS
Collectively, LDT409 represents a fatty acid mimetic that generates a uniquely favorable metabolic response for the treatment of multiple abnormalities including obesity, dyslipidemia, metabolic dysfunction-associated steatotic liver disease, and diabetes. LDT409 is derived from a highly abundant natural product-based starting material and its development could be pursued as a therapeutic solution to the global metabolic health crisis.
PubMed: 38763495
DOI: 10.1016/j.molmet.2024.101958 -
Molecular Metabolism May 2024Compromised hepatic fatty acid oxidation (FAO) has been observed in human MASH patients and animal models of MASLD/MASH. It remains poorly understood how and when the...
OBJECTIVES
Compromised hepatic fatty acid oxidation (FAO) has been observed in human MASH patients and animal models of MASLD/MASH. It remains poorly understood how and when the hepatic FAO pathway is suppressed during the progression of MASLD towards MASH. Hepatic ChREBP⍺ is a classical lipogenic transcription factor that responds to the intake of dietary sugars.
METHODS
We examined its role in regulating hepatocyte fatty acid oxidation (FAO) and the impact of hepatic Chrebpa deficiency on sensitivity to diet-induced MASLD/MASH in mice.
RESULTS
We discovered that hepatocyte ChREBP⍺ is both necessary and sufficient to maintain FAO in a cell-autonomous manner independently of its DNA-binding activity. Supplementation of synthetic PPAR⍺/δ agonist is sufficient to restore FAO in Chrebp primary mouse hepatocytes. Hepatic ChREBP⍺ was decreased in mouse models of diet-induced MAFSLD/MASH and in patients with MASH. Hepatocyte-specific Chrebp⍺ knockout impaired FAO, aggravated liver steatosis and inflammation, leading to early-onset fibrosis in response to diet-induced MASH. Conversely, liver overexpression of ChREBP⍺-WT or its non-lipogenic mutant enhanced FAO, reduced lipid deposition, and alleviated liver injury, inflammation, and fibrosis. RNA-seq analysis identified the CYP450 epoxygenase (CYP2C50) pathway of arachidonic acid metabolism as a novel target of ChREBP⍺. Over-expression of CYP2C50 partially restores hepatic FAO in primary hepatocytes with Chrebp⍺ deficiency and attenuates preexisting MASH in the livers of hepatocyte-specific Chrebp⍺-deleted mice.
CONCLUSIONS
Our findings support the protective role of hepatocyte ChREBPa against diet-induced MASLD/MASH in mouse models in part via promoting CYP2C50-driven FAO.
PubMed: 38740087
DOI: 10.1016/j.molmet.2024.101957 -
Phytomedicine : International Journal... Jul 2024Exercise is an effective strategy to prevent sarcopenia, but high physical inactivity in the elderly requires alternative therapeutic approaches. Exercise mimetics are...
BACKGROUND
Exercise is an effective strategy to prevent sarcopenia, but high physical inactivity in the elderly requires alternative therapeutic approaches. Exercise mimetics are therapeutic compounds that simulate the beneficial effects of exercise on skeletal muscles. However, the toxicity and adverse effects of exercise mimetics raise serious concerns.
PURPOSE
We aimed to search novel plant-based alternatives to activate exercise induced-signaling.
METHODS
We used open databases and luciferase assays to identify plant-derived alternatives to activate exercise-induced signaling and compared its efficacy to mild intensity continuous training (MICT) in aged C57BL/6 mice. The nineteen-month-old mice were either fed an experimental diet supplemented with the isolated alternative or subjected to MICT for up to 21 mo of age.
RESULTS
Our analysis revealed that Chrysanthemum zawadskii Herbich var latillobum (Maxim.) Kitamura (CZH), a medicinal plant rich in linarin, is a novel activator of peroxisome proliferator-activated receptor δ (PPARδ) and estrogen-related receptor γ (ERRγ), key regulators of exercise-induced positive effects on muscles. CZH supplementation ameliorated the loss of muscle function and mass, and increased PPARδ and ERRγ expression in mouse muscles. CZH also improved mitochondrial functions and proteostasis in aged mice, similar to MICT. Furthermore, CZH and linarin induced the activation of Sestrin 1, a key mediator of exercise benefits, in muscle. Silencing Sestrin 1 negated the increase in myogenesis and mitochondrial respiration by CZH and linarin in primary myoblasts from old mice.
CONCLUSION
Our findings suggest the potential of CZH as a novel plant-derived alternative to activate exercise-induced signaling for preventing sarcopenia in sedentary older adults. This could offer a safer therapeutic option for sarcopenia treatment.
Topics: Animals; Chrysanthemum; Mice, Inbred C57BL; Signal Transduction; Sarcopenia; Mice; Muscle, Skeletal; Physical Conditioning, Animal; Male; PPAR delta; Plant Extracts; Receptors, Estrogen; Humans; Aging; Glycosides
PubMed: 38728922
DOI: 10.1016/j.phymed.2024.155695 -
Bioorganic & Medicinal Chemistry Letters Jul 2024We have previously reported the total synthesis and structure-activity relationships (SAR) of 2-prenylated benzopyrans with PPAR agonist activity. Herein, we have...
We have previously reported the total synthesis and structure-activity relationships (SAR) of 2-prenylated benzopyrans with PPAR agonist activity. Herein, we have described the synthesis and PPAR activity of 2-prenylated benzopyrans and 2-prenylated quinolines. The benzopyran nucleus was generated via enamine-catalyzed Kabbe condensation, and the quinoline nucleus via Friedländer condensation. Results demonstrated that both benzopyran (5a) and quinoline (4b) derivatives bearing a γ,δ-unsaturated ester displayed a pan-PPAR agonism. They were full PPARα agonists, but showed different preferences for PPARγ and PPARβ/δ activation. It was noteworthy that quinoline 4b displayed full hPPARα activation (2-fold than WY-14,643), weak PPARβ/δ and partial PPARγ activation. In addition, quinoline 4b showed anti-inflammatory effects on macrophages by reducing LPS-induced expression of both MCP-1 and IL-6. Therefore, 4b emerges as a first-in-class promising hit compound for the development of potential therapeutics aimed at treating metabolic syndrome, metabolic dysfunction-associated fatty liver disease (MAFLD), and its associated cardiovascular comorbidities.
Topics: Metabolic Syndrome; Quinolines; Structure-Activity Relationship; Humans; Peroxisome Proliferator-Activated Receptors; Molecular Structure; Lipopolysaccharides; Anti-Inflammatory Agents; Macrophages; Dose-Response Relationship, Drug; Benzopyrans; Animals; Mice
PubMed: 38677560
DOI: 10.1016/j.bmcl.2024.129770 -
Fluids and Barriers of the CNS Apr 2024The blood-brain barrier (BBB) is pivotal for the maintenance of brain homeostasis and it strictly regulates the cerebral transport of a wide range of endogenous...
BACKGROUND
The blood-brain barrier (BBB) is pivotal for the maintenance of brain homeostasis and it strictly regulates the cerebral transport of a wide range of endogenous compounds and drugs. While fasting is increasingly recognized as a potential therapeutic intervention in neurology and psychiatry, its impact upon the BBB has not been studied. This study was designed to assess the global impact of fasting upon the repertoire of BBB transporters.
METHODS
We used a combination of in vivo and in vitro experiments to assess the response of the brain endothelium in male rats that were fed ad libitum or fasted for one to three days. Brain endothelial cells were acutely purified and transcriptionaly profiled using RNA-Seq. Isolated brain microvessels were used to assess the protein expression of selected BBB transporters through western blot. The molecular mechanisms involved in the adaptation to fasting were investigated in primary cultured rat brain endothelial cells. MCT1 activity was probed by in situ brain perfusion.
RESULTS
Fasting did not change the expression of the main drug efflux ATP-binding cassette transporters or P-glycoprotein activity at the BBB but modulated a restrictive set of solute carrier transporters. These included the ketone bodies transporter MCT1, which is pivotal for the brain adaptation to fasting. Our findings in vivo suggested that PPAR δ, a major lipid sensor, was selectively activated in brain endothelial cells in response to fasting. This was confirmed in vitro where pharmacological agonists and free fatty acids selectively activated PPAR δ, resulting in the upregulation of MCT1 expression. Moreover, dosing rats with a specific PPAR δ antagonist blocked the upregulation of MCT1 expression and activity induced by fasting.
CONCLUSIONS
Altogether, our study shows that fasting affects a selected set of BBB transporters which does not include the main drug efflux transporters. Moreover, we describe a previously unknown selective adaptive response of the brain vasculature to fasting which involves PPAR δ and is responsible for the up-regulation of MCT1 expression and activity. Our study opens new perspectives for the metabolic manipulation of the BBB in the healthy or diseased brain.
Topics: Rats; Male; Animals; Blood-Brain Barrier; PPAR delta; Endothelial Cells; Membrane Transport Proteins; Brain; Fasting
PubMed: 38589879
DOI: 10.1186/s12987-024-00526-8 -
Asian Pacific Journal of Cancer... Mar 2024The aim of the present study was to examine whether GLUT1 was involved in the antiproliferative activity of curcumin and doxorubicin by understanding mechanistically how...
OBJECTIVE
The aim of the present study was to examine whether GLUT1 was involved in the antiproliferative activity of curcumin and doxorubicin by understanding mechanistically how curcumin regulated GLUT1.
METHODS
Expression level of GLUT1 in MCF-7 and MDA-MB-231 cells were quantitated using quantitative real-time PCR and western blot. GLUT1 activity was inhibited in MDA-MB-231 cells with the pharmacological inhibitor WZB117 to assess the anti-proliferative effects of doxorubicin using MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide). To examine cell proliferation, trypan blue assay was used in cells transfected with GLUT1 siRNA or plasmid overexpressing GLUT1 with doxorubicin and/or commercially available curcumin. The role of PPARδ and Akt on the regulation of GLUT1 by curcumin was examined by overexpressing these proteins and western blot was employed to examine their protein expression.
RESULTS
The data revealed that there was a 1.5 fold increase in GLUT1 mRNA and protein levels in MDA-MB-231 compared to MCF-7. By inhibiting GLUT1 in triple negative breast cancer cell line, MDA-MB-231 with either the pharmacological inhibitor WZB117 or with GLUT1 siRNA, we observed the enhanced antiproliferative effects of doxorubicin. Additional observations indicated these effects can be reversed by the overexpression of GLUT1. Treatment of MDA-MB-231 with curcumin also revealed downregulation of GLUT1, with further growth suppressive effects when combined with doxorubicin. Overexpression of GLUT1 blocked the growth suppressive role of curcumin and doxorubicin (p< 0.05). Mechanistically, we also observed that the regulation of GLUT1 by curcumin was mediated by the Peroxisome proliferator-activated receptor (PPAR) δ/Akt pathway.
CONCLUSION
Our study demonstrates that regulation of GLUT1 by curcumin via the PPARδ/Akt signaling improves the efficacy of doxorubicin by promoting its growth inhibitory effects in MDA-MB-231 cells.
Topics: Humans; Female; Curcumin; MDA-MB-231 Cells; PPAR delta; Proto-Oncogene Proteins c-akt; Glucose Transporter Type 1; Doxorubicin; Cell Proliferation; RNA, Small Interfering; Breast Neoplasms; Cell Line, Tumor; Hydroxybenzoates
PubMed: 38546086
DOI: 10.31557/APJCP.2024.25.3.1035 -
Biomedicines Mar 2024Three peroxisome proliferator-activated receptor subtypes, PPARα, PPAR(ß/)δ, and PPARγ, exert ligand-dependent transcriptional control in concert with retinoid X...
Three peroxisome proliferator-activated receptor subtypes, PPARα, PPAR(ß/)δ, and PPARγ, exert ligand-dependent transcriptional control in concert with retinoid X receptors (RXRs) on various gene sets harboring PPAR response elements (PPREs) in their promoter regions. Ligand-bound PPAR/RXR complexes do not directly regulate transcription; instead, they recruit multiprotein coactivator complexes to specific genomic regulatory loci to cooperatively activate gene transcription. Several coactivators are expressed in a single cell; however, a ligand-bound PPAR can be associated with only one coactivator through a consensus LXXLL motif. Therefore, altered gene transcription induced by PPAR subtypes/agonists may be attributed to the recruitment of various coactivator species. Using a time-resolved fluorescence resonance energy transfer assay, we analyzed the recruitment of four coactivator peptides (PGC1α, CBP, SRC1, and TRAP220) to human PPARα/δ/γ-ligand-binding domains (LBDs) using eight PPAR dual/pan agonists (bezafibrate, fenofibric acid, pemafibrate, pioglitazone, elafibranor, lanifibranor, saroglitazar, and seladelpar) that are/were anticipated to treat nonalcoholic fatty liver disease. These agonists all recruited four coactivators to PPARα/γ-LBD with varying potencies and efficacy. Only five agonists (bezafibrate, pemafibrate, elafibranor, lanifibranor, and seladelpar) recruited all four coactivators to PPARδ-LBD, and their concentration-dependent responses differed from those of PPARα/γ-LBD. These results indicate that altered gene expression through consensus PPREs by different PPAR subtypes/agonists may be caused, in part, by different coactivators, which may be responsible for the unique pharmacological properties of these PPAR agonists.
PubMed: 38540237
DOI: 10.3390/biomedicines12030624 -
Biomedicines Feb 2024Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) that is characterized by hepatic inflammation and steatosis....
Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease (NAFLD) that is characterized by hepatic inflammation and steatosis. Currently, limited data exist regarding the risk of NASH in transgender women and the treatment options for this particular population. The use of testosterone supplementation is unfavorable for transgender women, and estrogen supplementation is linked to an increased risk of breast cancer; thus, an isoflavone derivative compound known as "genistein" could serve as a viable substitute for a hormone supplement in this context. The purpose of this study was to investigate the treatment effects and mechanisms of actions of genistein and sex hormones in orchidectomized (ORX) rats with nonalcoholic steatohepatitis induced via a high-fat high-fructose diet (HFHF) model. Male rats (n = 42) were randomly assigned into seven groups; control, ORX + standard diet, HFHF, ORX + HFHF, ORX + HFHF diet + testosterone (50 mg/kg body weight (BW) once weekly), ORX + HFHF diet + estradiol (1.6 mg/kg BW daily), and ORX + HFHF diet + genistein (16 mg/kg BW daily). The duration of the study was 6 weeks. Some parts of liver tissue were used for histological examination by H&E staining. The determination of fat accumulation was performed using Oil Red O staining. and gene expression were quantified using real-time PCR technique. The levels of all types of peroxisome proliferator-activated receptors (PPARs; α, δ, γ), proteins, and signal transducer and activator of transcription 1 (STAT1) signaling pathway were determined by both immunoblotting and immunohistochemistry. Rats in the ORX + HFHF group had the highest degree of hepatic steatosis, lobular inflammation, and hepatocyte ballooning, and showed higher levels of genes related to de novo lipogenesis, including and . The expression of PPARγ and STAT1 were upregulated, while the expression of PPARα and PPARδ were downregulated in the ORX + HFHF group. Testosterone, estradiol and genistein treatments improved NASH histopathology together with the reversal of all types of PPAR protein expressions. Interestingly, genistein decreased the levels of STAT1 protein expression more than those of testosterone and estradiol treatment. Genistein and sex hormone treatment could ameliorate NASH through the upregulation of PPARα, and PPARδ, and the suppression of PPARγ and STAT1 expression.
PubMed: 38540097
DOI: 10.3390/biomedicines12030483 -
PeerJ 2024Peroxisome proliferator-activated receptors (PPARs) exert multiple functions in the initiation and progression of stomach adenocarcinomas (STAD). This study analyzed the...
BACKGROUND
Peroxisome proliferator-activated receptors (PPARs) exert multiple functions in the initiation and progression of stomach adenocarcinomas (STAD). This study analyzed the relationship between PPARs and the immune status, molecular mutations, and drug therapy in STAD.
METHODS
The expression profiles of three PPAR genes (PPARA, PPARD and PPARG) were downloaded from The Cancer Genome Atlas (TCGA) dataset to analyze their expression patterns across pan-cancer. The associations between PPARs and clinicopathologic features, prognosis, tumor microenvironment, genome mutation and drug sensitivity were also explored. Co-expression between two PPAR genes was calculated using Pearson analysis. Regulatory pathways of PPARs were scored using gene set variation analysis (GSVA) package. Quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, Cell Counting Kit-8 (CCK-8) assay and transwell assay were conducted to analyze the expression and function of the PPAR genes in STAD cell lines (AGS and SGC7901 cells).
RESULTS
PPARA, PPARD and PPARG were more abnormally expressed in STAD samples and cell lines when compared to most of 32 type cancers in TCGA. In STAD, the expression of PPARD was higher in Grade 3+4 and male patients, while that of PPARG was higher in patient with Grade 3+4 and age > 60. Patients in high-PPARA expression group tended to have longer survival time. Co-expression analysis revealed 6 genes significantly correlated with the three PPAR genes in STAD. Single-sample GSEA (ssGSEA) showed that the three PPAR genes were enriched in 23 pathways, including MITOTIC_SPINDLE, MYC_TARGETS_V1, E2F_TARGETS and were closely correlated with immune cells, including NK_cells_resting, T_cells_CD4_memory_resting, and macrophages_M0. Immune checkpoint genes (CD274, SIGLEC15) were abnormally expressed between high-PPAR expression and low-PPAR expression groups. TTN, MUC16, FAT2 and ANK3 genes had a high mutation frequency in both high-PPARA/PPARG and low-PPARA/PPARG expression group. Fourteen and two PPARA/PPARD drugs were identified to be able to effectively treat patients in high-PPARA/PPARG and low-PPARA/PPARG expression groups, respectively. We also found that the chemotherapy drug Vinorelbine was positively correlated with the three PPAR genes, showing the potential of Vinorelbine to serve as a treatment drug for STAD. Furthermore, cell experiments demonstrated that PPARG had higher expression in AGS and SGC7901 cells, and that inhibiting PPARG suppressed the viability, migration and invasion of AGS and SGC7901 cells.
CONCLUSIONS
The current results confirmed that the three PPAR genes (PPARA, PPARD and PPARG) affected STAD development through mediating immune microenvironment and genome mutation.
Topics: Humans; Male; PPAR gamma; Vinorelbine; PPAR alpha; PPAR delta; Adenocarcinoma; Drug Resistance; Stomach; Tumor Microenvironment
PubMed: 38529307
DOI: 10.7717/peerj.17082