Upregulation Of PPARα Research Articles

Low GPR81 in ER+ breast cancer cells drives tamoxifen resistance through inducing PPARα-mediated fatty acid oxidation

AimsThe intricate molecular mechanisms underlying estrogen receptor-positive (ER+) breast carcinogenesis and resistance to endocrine therapy remain elusive. In this study, we elucidate the pivotal role of GPR81, a G protein-coupled receptor, in ER+ breast cancer (BC) by demonstrating low expression of GPR81 in tamoxifen (TAM)-resistant ER+ BC cell lines and tumor samples, along with the underlying molecular mechanisms. Main methodsFatty acid oxidation (FAO) levels and lipid accumulation were explored using MDA and FAβO assay, BODIPY 493/503 staining, and Lipid TOX staining. Autophagy levels were assayed using CYTO-ID detection and Western blotting. The impact of GPR81 on TAM resistance in BC was investigated through CCK8 assay, colony formation assay and a xenograft mice model. ResultsAberrantly low GPR81 expression in TAM-resistant BC cells disrupts the Rap1 pathway, leading to the upregulation of PPARα and CPT1. This elevation in PPARα/CPT1 enhances FAO, impedes lipid accumulation and lipid droplet (LD) formation, and subsequently inhibits cell autophagy, ultimately promoting TAM-resistant BC cell growth. Moreover, targeting GPR81 and FAO emerges as a promising therapeutic strategy, as the GPR81 agonist and the CPT1 inhibitor etomoxir effectively inhibit ER+ BC cell and tumor growth in vivo, re-sensitizing TAM-resistant ER+ cells to TAM treatment. ConclusionOur data highlight the critical and functionally significant role of GPR81 in promoting ER+ breast tumorigenesis and resistance to endocrine therapy. GPR81 and FAO levels show potential as diagnostic biomarkers and therapeutic targets in clinical settings for TAM-resistant ER+ BC.

Macrophage Targeted Dendrimer-Tesaglitazar Therapy for Atherosclerosis

Background: Atherosclerosis is a leading contributor to cardiovascular disease, the number one cause of death globally. Although atherosclerosis is clearly a multicellular disease that also affects endothelial cells as well as smooth muscle cells of arteries, it is increasingly recognized as an inflammatory disease. Our goal is to determine if targeting immune cells implicated in atherosclerosis can halt plaque accumulation and resulting derangement of vascular cells in the aorta. Peroxisome proliferator activated receptors (PPARs) within macrophages present a promising therapeutic target as PPAR-α and PPAR-γ agonists have been shown to improve lipid metabolism and inhibit macrophage foam cell formation. However, due to high doses required and associated side effects, clinical translation was halted. We target anti-atherogenic pathways in immune cells using the novel treatment D-Tesa, a dendrimer conjugate of a dual PPAR-α/γ agonist, Tesaglitazar. Methods: 25-week-old, male, apolipoprotein E knockout (ApoE−/−) mice were fed high fat diet (HFD) for 16 weeks to induce atherosclerosis and randomized into two groups: 1) treatment group: D-Tesa for 6 weeks (20μg/kg twice weekly by oral gavage and 2) untreated group. HFD was continued for the duration of the study. Pulse wave velocity (PWV: Doppler), blood pressure (BP: tail cuff on trained, conscious mice), and body weight were monitored. Dendrimer mediated delivery of drug payload to plaque macrophages was studied using D-Cy5, a fluorescently labeled dendrimer, in an atherosclerotic mouse. Aortas were isolated and used for vasoreactivity studies and western blot analysis. THP-1 cell derived foam cells were used to study D-Tesa’s mechanism of action in vitro. Results: Immunofluorescence staining and confocal microscopy revealed that D-Cy5 localized in macrophages within the atherosclerotic plaque in ApoE−/− mice on HFD, indicating that the dendrimer can deliver drugs specifically into the plaque. D-Tesa slowed plaque progression, preserved endothelial function, and decreased arterial stiffness. BP was similar and unchanged between groups. D-Tesa surprisingly decreased body weight, which was the opposite effect observed from the free drug in clinical trials. Western blotting of aorta revealed that D-Tesa treated mice experienced an upregulation of PPAR-α, PPAR-γ, and ABCA1. The in vitro studies with THP-1 derived foam cells confirmed the upregulation of the cholesterol efflux pathway and anti-inflammatory benefit of D-Tesa. Conclusion: D-Tesa offers a novel therapy to ameliorate multiple damaging consequences of atherosclerosis on the cardiovascular system including improvements in plaque burden, endothelial function, arterial stiffness, and body weight in an ApoE−/− model of atherosclerosis. Excitingly, these effects were seen at 2-15 times lower doses despite continued HFD than those reported in literature with a combination of free Tesa and low-fat diet. Thus, D-Tesa offers great translational relevance because of potential reduction in negative side effects and higher patient benefit due to noted lack of compliance with dietary changes in the clinic. Further research is ongoing to evaluate sex differences, dose response, and long-term effects of this highly promising therapy. This work was supported by a NHLBI grant R01HL148112 01 (L.S.) and the Traystman Endowment (S.K.). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Oxidative stress, inflammation, and steatosis elucidate the complex dynamics of HgCl2 induced liver damage in Channa punctata

Water bodies are highly pollution-prone areas in which mercury (Hg) is considered as a major menace to aquatic organisms. However, the information about the toxicity of mercuric chloride (HgCl2) in a vital organ such as the liver of fish is still inadequate. This study aimed to assess the impact of mercuric chloride (HgCl2) exposure on the liver of Channa punctata fish over 15, 30, and 45 days, at two different concentrations (0.039 mg/L and 0.078 mg/L). Mercury is known to be a significant threat to aquatic life, and yet, information regarding its effects on fish liver remains limited. The results of this study demonstrate that exposure to HgCl2 significantly increases oxidative stress markers, such as lipid peroxidation (LPO) and protein carbonyls (PC), as well as the levels of serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) in the fish. Additionally, the transcriptional and protein analysis of specific genes and molecules associated with necroptosis and inflammation, such as ABCG2, TNF α, Caspase 3, RIPK 3, IL-1β, Caspase-1, IL-18, and RIPK1, confirm the occurrence of necroptosis and inflammation in the liver. Histopathological and ultrastructural examinations of the liver tissue further reveal a significant presence of liver steatosis. Interestingly, the upregulation of PPARα suggests that the fish's body is actively responding to counteract the effects of liver steatosis. This study provides a comprehensive analysis of oxidative stress, biochemical changes, gene expression, protein profiles, and histological findings in the liver tissue of fish exposed to mercury pollution in freshwater environments.

Genistein and Sex Hormone Supplementation Modulated Hepatic PPARα, δ, and γ Subtypes and STAT1 Expressions in a NASH Rat Model with Bilateral Orchidectomy.

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 Sprague-Dawley 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. SREBP1c and FAS 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 SREBP1c and FAS. 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.

Dysregulated palmitic acid metabolism promotes the formation of renal calcium-oxalate stones through ferroptosis induced by polyunsaturated fatty acids/phosphatidic acid

The pathogenesis of renal calcium-oxalate (CaOx) stones is complex and influenced by various metabolic factors. In parallel, palmitic acid (PA) has been identified as an upregulated lipid metabolite in the urine and serum of patients with renal CaOx stones via untargeted metabolomics. Thus, this study aimed to mechanistically assess whether PA is involved in stone formation. Lipidomics analysis of PA-treated renal tubular epithelial cells compared with the control samples revealed that α-linoleic acid and α-linolenic acid were desaturated and elongated, resulting in the formation of downstream polyunsaturated fatty acids (PUFAs). In correlation, the levels of fatty acid desaturase 1 and 2 (FADS1 and FADS2) and peroxisome proliferator-activated receptor α (PPARα) in these cells treated with PA were increased relative to the control levels, suggesting that PA-induced upregulation of PPARα, which in turn upregulated these two enzymes, forming the observed PUFAs. Lipid peroxidation occurred in these downstream PUFAs under oxidative stress and Fenton Reaction. Furthermore, transcriptomics analysis revealed significant changes in the expression levels of ferroptosis-related genes in PA-treated renal tubular epithelial cells, induced by PUFA peroxides. In addition, phosphatidyl ethanolamine binding protein 1 (PEBP1) formed a complex with 15-lipoxygenase (15-LO) to exacerbate PUFA peroxidation under protein kinase C ζ (PKC ζ) phosphorylation, and PKC ζ was activated by phosphatidic acid derived from PA. In conclusion, this study found that the formation of renal CaOx stones is promoted by ferroptosis of renal tubular epithelial cells resulting from PA-induced dysregulation of PUFA and phosphatidic acid metabolism, and PA can promote the renal adhesion and deposition of CaOx crystals by injuring renal tubular epithelial cells, consequently upregulating adhesion molecules. Accordingly, this study provides a new theoretical basis for understanding the correlation between fatty acid metabolism and the formation of renal CaOx stones, offering potential targets for clinical applications.

Co-treatment of Astragaloside IV with Vitamin D in Diabetic Peripheral Neuropathic Rats: Protective Effects and Potential Mechanisms.

The potential mechanism underlying the protective effect of Astragaloside IV (AS-IV) co-treatment with 1, 25-dihydroxy-vitamin D (Vit-D) on neuropathy in diabetic high-fat rats was investigated. The rat diabetic hyperlipidemia (DH) model was established via streptozotocin and a high-fat diet (HFD). After co-treatment (of AS-IV and Vit-D at respective doses of 50 mg/kg via oral gavage and 30000 IU/kg via intramuscular injection), blood glucose levels, markers of inflammation and oxidative stress, as well as apoptosis and histopathology were evaluated with appropriate techniques. Co-treatment could effectively reduce blood glucose levels substantially (p< 0.01), improve weight loss, and decrease oral glucose tolerance. Reduced respective sensory and motor nerve conduction velocities in rats were substantially improved (p<0.01) after co-treatment. Also, we observed obvious improvement in DH-induced injured nerve fiber myelin structure and other organ pathologies in co-treated rats. Besides, we observed up-regulated expressions of peroxisomal-proliferator activated receptor-alpha (PPAR-α) and Vit-D receptors (VDR) (p< 0.01) through the western blotting technique. Using the same technique, we also discovered reduced levels of interleukin (IL)1 beta, IL-6, and tumor necrosis factor-alpha, coupled with increased IL-10 and superoxide dismutase levels (p< 0.01). Importantly, co-treatment could effectively exert antioxidative and anti-inflammatory effects. Also, co-treatment resulted in the up-regulation of PPAR-α and VDR expressions, inhibition of the renin-angiotensin-aldosterone system, and promotion of β-cell sensitivity to insulin. The combined application of AS-IV and Vit-D exhibited health effects such as anti-oxidation, regulation of inflammatory factors, and promotion of cell repair, which may be considered as the mechanisms underlying treatment of diabetic peripheral neuropathy and improvement in biochemical indicators.

Effects of (-)-epicatechin on hepatic triglyceride metabolism.

(-)-Epicatechin (EC) consumption is associated with an improvement of hyperlipemia and other metabolic changes linked to obesity and western-style diets. This work investigated the effects of EC on triglyceride (TG) metabolism both in vivo, where mice were supplemented with EC (2 and 20 mg EC per kg body weight), and in vitro, when human HepG2 hepatocytes were incubated in the presence of EC and the main EC metabolites found in human plasma. Increased hepatic TG levels were only observed after 24 weeks supplementation with EC (20 mg per kg body weight), with a preserved liver structure and absence of inflammation or oxidative stress. EC caused increased expression of diacylglycerol acyltransferases (DGAT2), key enzymes in TG synthesis, and the upregulation of PPARα, which promotes free fatty acid (FFA) oxidation. On the other hand, incubation of HepG2 cells in the presence of high concentrations of EC (1-10 μM) did not affect TG deposition nor DGAT2 expression. In summary, in mouse liver, EC upregulated mechanisms that can neutralize the potential toxicity of FFA, i.e. TG synthesis and FFA β-oxidation. Results in mouse liver and HepG2 cells stress the safety of EC in terms of TG metabolism and development of hepatopathies in doses within the limits given by a rational time and dose for human consumption.

Tofogliflozin attenuates renal lipid deposition and inflammation via PPARα upregulation mediated by miR-21a impairment in diet-induced steatohepatitic mice.

We previously demonstrated hepatic, cardiac, and skin inflammation in a high-fat diet-induced steatotic liver disease (SLD) model. However, the molecular mechanism in the kidneys in this model remains unclear. It has been recently reported that SGLT2 inhibitors improve chronic kidney disease (CKD). Therefore, we used this model to evaluate the effects of tofogliflozin on renal lipid metabolism and inflammation. Male 8-10-week-old C57Bl/6 mice were fed a high-fat/high-cholesterol/high-sucrose/bile acid (HF/HC/HS/BA) diet with 0.015% tofogliflozin (Tofo group) or an HF/HC/HS/BA diet alone (SLD group). After eight weeks, serum lipid profiles, histology, lipid content, and mRNA/microRNA and protein expression levels in the kidney were examined. The Tofo group showed significant reductions in body (26.9 ± 0.9 vs. 24.5 ± 1.0 g; p < 0.001) and kidney weight compared to those of the SLD group. Renal cholesterol (9.1 ± 1.6 vs. 7.5 ± 0.7 mg/g; p < 0.05) and non-esterified fatty acid (NEFA) (12.0 ± 3.0 vs. 8.4 ± 1.5 μEq/g; p < 0.01) were significantly decreased in the Tofo group. Transmission electron microscopy revealed the presence of fewer lipid droplets. mRNA sequencing analysis revealed that fatty acid metabolism-related genes were upregulated and NFκB signaling pathway-related genes were downregulated in the Tofo group. MicroRNA sequencing analysis indicated that miR-21a was downregulated and miR-204 was upregulated in the Tofo group. Notably, the expression of PPARα, which has been known to be negatively regulated by miR-21, was significantly increased, leading to enhancing β-oxidation genes, Acox1 and Cpt1 in the Tofo group. Tofogliflozin decreased renal cholesterol and NEFA levels and improved inflammation through the regulation of PPARα and miR-21a.

GW9662 ameliorates nonalcoholic steatohepatitis by inhibiting the PPARγ/CD36 pathway and altering the gut microbiota

Background & aimsPeroxisome proliferator-activated receptors (PPARs) are currently among the most focused-on therapeutic targets for non-alcoholic steatohepatitis (NASH), although no clinical transformation has been achieved to date. In this study, we aimed to evaluate the effects of GW9662 on choline-deficient, L-amino acid-defined high-fat diet (CDAA-HFD)-induced NASH mice and reveal the mechanism underlying this effect. MethodsGW9662 (1 mg/kg) was administered in CDAA-HFD mouse model of NASH. The effect of GW9662 on hepatic lipid metabolism was investigated using liver RNA-seq and HepG2 cells induced by oleic acid and palmitic acid. In addition, 16S rRNA gene sequencing was performed to analyze the effects of GW9662 on the composition and function of the fecal microbiota. ResultsGW9662 improved the CDAA-HFD caused elevation in the levels of ALT, AST, hepatic free fatty acids and triglycerides. The liver pathological analysis indicated that GW9662 alleviated the hepatic steatosis and fibrosis. The NAFLD activity score and RNA-Seq revealed that GW9662 mainly regulated the fatty acids transport and lipid synthesis by inhibiting PPARγ, CD36, FABP1, FASN, and SCD1, and through the up-regulation of PPARα. Moreover, GW9662 reduced the epididymal fat weight. GW9662 reversed the gut microbiota disorder by increasing the abundance of the beneficial bacteria Dubosiella and Lactobacillus and decreasing the abundance of harmful bacteria Lachnospiraceae_NK4A136_group, Helicobacteraceae, Desulfovibriaceae, and Rickenaceae. ConclusionsGW9662 ameliorated lipid metabolism by inhibiting the PPARγ/CD36 pathway and altering the composition of the gut microbiota in NASH mice. Therefore, the PPARγ antagonist GW9662 deserves more attention as a potential therapeutic agent for NASH.

NPRA promotes fatty acid metabolism and proliferation of gastric cancer cells by binding to PPARα

Among cancers, gastric cancer (GC) ranks third globally in morbidity and mortality, particularly in East Asia. Natriuretic peptide receptor A (NPRA), a receptor for guanylate cyclase, plays important roles in regulating water and sodium balance. Recent studies have suggested that NPRA is involved in tumorigenesis, but its role in GC development remains unclear. Herein, we showed that the expression level of NPRA was positively correlated with gastric tumor size and clinical stage. Patients with high NPRA expression had a lower five-year survival rate than those with low expression, and NPRA was identified as an independent predictor of GC prognosis. NPRA knockdown suppressed GC cell proliferation, migration and invasion. NPRA overexpression enhanced cell malignant behavior. Immunohistochemistry of collected tumor samples showed that tumors with high NPRA expression had higher peroxisome proliferator-activated receptor α (PPARα) levels. In vivo and in vitro studies showed that NPRA promotes fatty acid oxidation and tumor cell metastasis. Co-IP showed that NPRA binds to PPARα and prevents PPARα degradation. PPARα upregulation under NPRA protection activates arnitine palmitoyl transferase 1B (CPT1B) to promote fatty acid oxidation. In this study, new mechanisms by which NPRA promotes the development of GC and new regulatory mechanisms of PPARα were identified.

Chromium Nanoparticles Together with a Switch Away from High-Fat/Low-Fiber Dietary Habits Enhances the Pro-Healthy Regulation of Liver Lipid Metabolism and Inflammation in Obese Rats.

The study on Wistar rats was conducted to investigate the effects of a pharmacologically relevant dose 0.3 mg/kg body weight of chromium supplementation (commonly used picolinate or novel form as nanoparticles) and switching away from obesogenic dietary habits on the parameters of lipid metabolism, inflammation, and oxidative stress in liver and plasma. Favorable effects related to dietary changes from the obesogenic diet were considerably enhanced when the diet was supplemented with chromium nanoparticles. This combination exerted the strongest fat content and cholesterol reduction in the liver. Moreover, in this group, a favorable antioxidative effect was observed through GSH/GSSG elevation in the liver as well as ALT activity reduction in the plasma and IL-6 levels in the liver. The molecular mechanisms associated with regulating lipid metabolism, oxidative stress and inflammation might be related to lower expression of HIF-1α, COX-2, and LOX-1 and upregulation of PPARα in the liver. Supplementation with chromium nanoparticles without changes in the obesogenic diet also favorably affected lipid metabolism and oxidative stress in the liver; however, the examined effects were moderate. In conclusion, the favorable effects of switching from an obesogenic to a balanced diet on hepatic lipid metabolism, oxidative stress, and inflammation induced by an obesogenic diet might be enhanced by supplementation with chromium nanoparticles.

Suppression of Hepatic PPARα in Primary Biliary Cholangitis Is Modulated by miR-155.

Background: PPARα is a ligand-activated transcription factor that shows protective effects against metabolic disorders, inflammation and apoptosis. Primary biliary cholangitis and primary sclerosing cholangitis result in the intrahepatic accumulation of bile acids that leads to liver dysfunction and damage. Small, non-coding RNAs such as miR-155 and miR-21 are associated with silencing PPARα. Methods: The expression of miR-155, miR-21 and PPARα were evaluated using real-time PCR on liver tissue, as well as on human hepatocytes (HepG2) or cholangiocytes (NHCs) following exposure to lipopolysaccharide (LPS), glycodeoxycholic acid (GCDCA), lithocholic acid (LCA) and/or ursodeoxycholic acid (UDCA). Results: A reduction of PPARα in primary biliary cholangitis (PBC) livers was associated with miR-21 and miR-155 upregulation. Experimental overexpression of either miR-155 or miR-21 inhibited PPARα in hepatocytes, whereas, in cholangiocytes, only miR-21 suppressed PPARα. Both GCDCA and LCA induced the cell type-specific upregulation of miR-155 or miR-21. In HepG2, LPS-induced miR-155 expression was blocked by a cotreatment with UDCA and was associated with PPARα upregulation. In NHC cells, the expression of miR-21 was induced by LPS but did not affect PPARα expression. Conclusions: Hepatic PPARα expression is reduced in PBC livers as a likely result of miR-155 overexpression. UDCA effectively reduced both baseline and LPS-induced miR-155 expression, thus preventing the suppression of PPARα.

Effect of Siberian Ginseng Water Extract as a Dietary Additive on Growth Performance, Blood Biochemical Indexes, Lipid Metabolism, and Expression of PPARs Pathway-Related Genes in Genetically Improved Farmed Tilapia (Oreochromis niloticus)

Overnutrition in high-density aquaculture can negatively affect the health of farmed fish. The Chinese herbal medicine Siberian ginseng (Acanthopanax senticosus, AS) can promote animal growth and immunity, and regulate lipid metabolism. Therefore, we conducted an 8-week experiment, in which Oreochromis niloticus was fed with a diet supplemented with different concentrations of AS water extract (ASW) (0‰, 0.1‰, 0.2‰, 0.4‰, 0.8‰, and 1.6‰). The ASW improved the growth performance and increased the specific growth rate (SGR). Linear regression analysis based on the SGR estimated that the optimal ASW amount was 0.74‰. Dietary supplementation with 0.4–0.8‰ ASW reduced the triglyceride and total cholesterol levels in the serum and liver, and regulated lipid transport by increasing the high-density lipoprotein cholesterol concentration and lowering the low-density lipoprotein cholesterol concentration. Dietary supplementation with ASW increased the activities of superoxide dismutase and catalase in the liver, thereby improving the antioxidant capacity. Moreover, ASW modulated the transcription of genes in the peroxisome proliferator-activated receptor signaling pathway in the liver (upregulation of PPARα, APOA1b, and FABP10a and downregulation of PPARγ), thereby regulating fatty acid synthesis and metabolism and slowing fat deposition. These results showed that 0.4–0.8‰ ASW can slow fat deposition and protected the liver from cell damage and abnormal lipid metabolism.

Dibutylstannanediyl (2Z,2′Z)-bis(4-(benzylamino)-4-oxobut-2-enoate inhibits prostate cancer progression by activating p38 MAPK/PPARα/SMAD4 signaling

Organotin (IV) compounds are a focus of research for potential use in cancer chemotherapy. Here, we established anticancer profile of dibutyltin (IV) carboxylate derivatives in prostate cancer (PCa) model. We determined cytotoxicity of a library of dibutyltin (IV) carboxylate derivatives and observed that dibutylstannanediyl (2Z,2′Z)-bis(4-(benzylamino)-4-oxobut-2-enoate (Ch-620; 10 μM) was minimally toxic to normal fibroblasts. Ch-620 (1–1.25 μM) inhibited proliferation of PCa and melanoma cells on short- and long-term exposures with induction of cell cycle arrest. Ch-620 treatment increased population of apoptotic cells, as assessed by flow cytometry, and activated caspase 3. Proteomics showed activation of PPARα, with repression of SMAD4 and integrin β5 (ITGB5) in Ch-620-treated PCa cells. Further analysis demonstrated that Ch-620 resulted in phosphorylation of p38 MAPK, upregulation of PPARα and decreased expression of SMAD4 and ITGB5 with reduced migration of PCa cells. In vivo studies in PC3M grafted athymic nude mice showed that Ch-620 (5 μg/week; 7 weeks) treatment reduced tumor growth as opposed to untreated controls. Immunoblot analysis of tumors demonstrated upregulated p-p38 MAPK and PPARα, followed by a decline in SMAD4 and ITGB5. Immunohistochemistry reinforced these results with increased caspase 3 and p-p38 MAPK and diminished Ki67 staining in Ch-620 treated animals. Taken together, our data indicate that Ch-620 inhibited proliferation of PCa through modulation of MAPK/PPARα/SMAD4 signaling. Organotin (IV) carboxylate compounds; specifically Ch-620 can be a potential anticancer agent for the treatment of PCa subject to detailed pre-clinical and clinical investigations. This unlocks prospects for the development of new tin-based drugs in cancer therapeutics.

Resveratrol attenuates against high-fat-diet-promoted non-alcoholic fatty liver disease in rats mainly by targeting the miR-34a/SIRT1 axis

This study evaluated if miR-34a/SIRT1 signalling mediates the anti-hepatosteatotic effect of resveratrol (RSV) in high-fat-diet (HFD)-fed rats. Rats were divided into seven groups (n = 6/each) as control, control + miR-34a agomir negative control, HFD, HFD + miR-34a, HFD + RSV, HFD + RSV + Ex-527 (a SIRT1 inhibitor), and HFD + RSV + miR-34a agomir. After 8 weeks, RSV suppressed dyslipidemia, lowered fasting glucose and insulin levels, improved insulin sensitivity, and prevented hepatic lipid accumulation. These effects were associated with hepatic downregulation of SREBP1 and SREBP2, upregulation of PPARα, and acetylation of Nrf2 (activation) and NF-κβ p65 (inhibition). Also, RSV reduced the transcription of miR-34a and increased the nuclear localisation of SIRT1 in the livers, muscles, and adipose tissues of HFD-fed rats. All these effects were prevented by EX-527 and miR-34a agmir. In conclusion, RSV prevents HFD-induced insulin resistance and hepatic steatosis by suppressing miR-34a-induced activation of SIRT1.

Salidroside inhibits insulin resistance and hepatic steatosis by downregulating miR-21 and subsequent activation of AMPK and upregulation of PPARα in the liver and muscles of high fat diet-fed rats

This study evaluated if salidroside (SAL) alleviates high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD) by downregulating miR-21. Rats (n = 8/group) were treated for 12 weeks as normal diet (control/ND), ND + agmoir negative control (NC) (150 µg/kg), ND + SAL (300 mg/kg), HFD, HFD + SAL, HFD + compound C (an AMPK inhibitor) (200 ng/kg), HFD + SAL + NXT629 (a PPAR-α antagonist) (30 mg/kg), and HFD + SAL + miR-21 agomir (150 µg/kg). SAL improved glucose and insulin tolerance and preserved livers in HFD-fed rats. In ND and HFD-fed rats, SAL reduced levels of serum and hepatic lipids and the hepatic expression of SREBP1, SREBP2, fatty acid (FA) synthase, and HMGCOAR. It also activated hepatic Nrf2 and increased hepatic/muscular activity of AMPK and levels of PPARα. All effects afforded by SAL were prevented by CC, NXT629, and miR-21 agmoir. In conclusion, activation of AMPK and upregulation of PPARα mediate the anti-steatotic effect of SAL.

Lanzhang Granules Ameliorate Nonalcoholic Fatty Liver Disease by Regulating the PPARα Signaling Pathway

Background There is still a lack of effective therapeutic drugs for nonalcoholic fatty liver disease (NAFLD) to date. In this study, we applied mouse model experiments to clarify the effect of Chinese herbal medicine “Lanzhang Granules (LZG)” on NAFLD and further explore the potential mechanism to provide an alternative method for NAFLD treatment. Methods Male C57BL/6J mice were fed with a high-fat diet (HFD) for twenty-two weeks to induce the NAFLD model. LZG intervention was then performed by gavage daily for another eight weeks. At the end of the treatment, serum and liver tissues were collected. Serum biochemical indexes, insulin levels, and liver histopathology were measured to assess the effect of LZG on NAFLD. The liver tissues were then analyzed by RNA sequence for differentially expressed genes and signaling pathways. Results were further analyzed by Protein-Protein Interaction (PPI) networks between the LZG and model groups. The selected different genes and signaling pathways were further verified by RT-PCR and Western blot analysis. Moreover, alpha mouse liver 12 (AML12) cells with lipid accumulation induced by fatty acid were treated with LZG, Fenofibrate (PPARα agonist), or Gw6471 (PPARα antagonist) to confirm the potential pharmacological mechanism. Results LZG was found to downregulate liver weight, body weight, liver index, and serum levels of ALT, AST, and serum lipid in HFD-induced NAFLD mice. HE and Oil Red O staining showed the improvement of hepatic steatosis and inflammatory infiltration in the mice with LZG treatment. The homeostasis model assessment-insulin resistance (HOMA-IR) index indicated that LZG improved the insulin resistance of NAFLD mice. The RNA sequencing and PPI analysis confirmed the role of LZG in lipid metabolism regulation and identified the peroxisome proliferator-activated receptor alpha (PPARα) signaling pathway as one of the major underlying mechanisms. Western blot and RT-PCR results verified the regulatory effect of LZG on the PPARα pathway, including the upregulation of PPARα, acyl-coenzyme A oxidase 1 (ACOX1), and enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase (EHHADH) and the downregulation of TNFα. In vitro experiments showed the effect of LZG in improving lipid accumulation and cell viability in AML12 cells induced by fatty acids, which were alleviated by Gw6471 coincubation. Gw6471could also reverse the transcription of PPAR target genes ACOX1 and EHHADH, which were upregulated by LZG treatment. Conclusion LZG can improve NAFLD in mice or cell models. A major underlying mechanism may be the regulation of the PPARα signaling pathway to improve lipid metabolism and inhibit the inflammatory response. This study will help to promote the clinical application of LZG for the treatment of NAFLD.

Cardioprotective properties of Artemisia herba alba nanoparticles against heart attack in rats: A study of the antioxidant and hypolipidemic activities

Recently, pharmaceutical scientists' interest has increased to find novel pharmaceutical natural substances with potent antioxidant capacity and very low side effects to be used safely in preventive medicine. One of the most common types of diseases with a large spread globally is cardiovascular diseases, which cause a high rate of deaths annually. The present study evaluated the use of Artemisia herba alba leaves’ extract (AHALE) and AHALE zinc oxide nanoparticles (AHALE–ZnONPs) against isoproterenol (ISO) inducing myocardial infarction (MI) in male rats. Several groups of Wistar male rats fed a high-fat diet (HFD) were pretreated with several doses of AHALE or AHALE–ZnONPs for one month followed by exposure to ISO for two days. After treatment, samples of the rats’ heart tissues and blood were collected for several molecular biological and biochemical analyses. Heart enzymes, antioxidant enzymes, lipid peroxidation compounds, lipid markers, activities, ROS generation, apoptosis, DNA damage and expression of lipid metabolism genes were analyzed in rats pretreated with AHALE or AHALE–ZnONPs followed by exposure to ISO. The results showed an increase in the levels of AST, ALT, LDH, CK, CK-MB, and cTnT (heart markers), elevation in TG, TC, and LDL levels (lipid profile markers), levels of TBARS and LOOH (lipid peroxidation products), ROS generation, DNA damage, apoptosis, and upregulation of PPAR-α, ADD1, FASN, and ACC genes in animals exposed to ISO in comparison with the control animals. Moreover, a decrease in antioxidant enzyme activities, including GPx, GRx, and GST, was observed in animals exposed to ISO in comparison with control rats. In male rats pretreated with AHALE or AHALE–ZnONPs followed by exposure to ISO, the oxidative stress induced by ISO was prevented. The results suggest that Artemisia extract could be considered for use as one of the natural compounds for prevention of atherosclerosis and heart diseases due to its high antioxidant and hypolipidemic activities. The reduced oxidative stress of Artemisia extract may be a result of the existence of flavonoids and phenolic substances.

Beta vulgaris L. (Beetroot) Methanolic Extract Prevents Hepatic Steatosis and Liver Damage in T2DM Rats by Hypoglycemic, Insulin-Sensitizing, Antioxidant Effects, and Upregulation of PPARα.

Simple SummaryBeetroot is one of the most consumable plants across the world. Previous studies have shown many health benefits of beetroot, with evidence of having potent hypoglycemic, antioxidant, and anti-inflammatory effects. The data obtained from this study further confirmed this effect in streptozotocin-diabetic animals. They showed the ability of methanolic beetroot extract to prevent the associated hepatic oxidative stress, inflammation, steatosis, and dyslipidaemia. However, the protection mechanisms involve, at least, upregulation of endogenous antioxidants, anti-apoptotic Bcl2, and PPARα.The present study examined if methanolic beetroot extract (BE) could prevent dyslipidemia and hepatic steatosis and damage in a type-2 diabetes mellitus (T2DM) rat model and studied some mechanisms of action. T2DM was induced in adult male Wistar rats by a low single dose of streptozotocin (STZ) (35 mg/kg, i.p) and a high-fat diet (HFD) feeding for 5 weeks. Control or T2DM rats then continued on standard or HFDs for another 12 weeks and were treated with the vehicle or BE (250 or 500 mg/kg). BE, at both doses, significantly improved liver structure and reduced hepatic lipid accumulation in the livers of T2DM rats. They also reduced body weight gain, serum glucose, insulin levels, serum and hepatic levels of cholesterol, triglycerides, free fatty acids, and serum levels of low-density lipoproteins in T2DM rats. In concomitant, they significantly reduced serum levels of aspartate and alanine aminotransferases, hepatic levels of malondialdehyde, tumor-necrosis factor-α, interleukin-6, and mRNA of Bax, cleaved caspase-3, and SREBP1/2. However, both doses of BE significantly increased hepatic levels of total glutathione, superoxide dismutase, and mRNA levels of Bcl2 and PPARα in the livers of both the control and T2DM rats. All of these effects were dose-dependent and more profound with doses of 500 mg/kg. In conclusion, chronic feeding of BE to STZ/HFD-induced T2DM in rats prevents hepatic steatosis and liver damage by its hypoglycemic and insulin-sensitizing effects and its ability to upregulate antioxidants and PPARα.

Lactiplantibacillusplantarum ATG-K2 Exerts an Anti-Obesity Effect in High-Fat Diet-Induced Obese Mice by Modulating the Gut Microbiome.

Obesity is a major health problem. Compelling evidence supports the beneficial effects of probiotics on obesity. However, the anti-obesity effect of probiotics remains unknown. In this study, we investigated the anti-obesity effects and potential mechanisms of Lactiplantibacillus plantarum ATG-K2 using 3T3-L1 adipocytes and high-fat diet (HFD)-induced obese mice. 3T3-L1 cells were incubated to determine the effect of lipid accumulation with lysate of L. plantarum ATG-K2. Mice were fed a normal fat diet or HFD with L. plantarum ATG-K2 and Orlistat for 8 weeks. L. plantarum ATG-K2 inhibited lipid accumulation in 3T3-L1 adipocytes, and reduced body weight gain, WAT weight, and adipocyte size in HFD-induced obese mice, concurrently with the downregulation of PPARγ, SREBP1c, and FAS and upregulation of PPARα, CTP1, UCP1, Prdm16, and ND5. Moreover, L. plantarum ATG-K2 decreased TG, T-CHO, leptin, and TNF-α levels in the serum, with corresponding gene expression levels in the intestine. L. plantarum ATG-K2 modulated the gut microbiome by increasing the abundance of the Lactobacillaceae family, which increased SCFA levels and branched SCFAs in the feces. L. plantarum ATG-K2 exhibited an anti-obesity effect and anti-hyperlipidemic effect in 3T3-L1 adipocytes and HFD-induced obese mice by alleviating the inflammatory response and regulating lipid metabolism, which may be influenced by modulation of the gut microbiome and its metabolites. Therefore, L. plantarum ATG-K2 can be a preventive and therapeutic agent for obesity.