Search Results (185)

Cholesterol stress profoundly modulates cellular processes, but its underlying mechanisms remain incompletely understood. To investigate cholesterol-responsive networks, we performed integrated transcriptome (RNA-seq) and metabolome (LC-MS) analyses on HeLa cells treated with cholesterol for 6 and 24 h. Through transcriptomic analysis of cholesterol-stressed HeLa cells, we identified stage-specific responses characterized by early-phase stress responses and late-phase immune-metabolic coordination. This revealed 1340 upregulated and 976 downregulated genes after a 6 h cholesterol treatment, including induction and suppression of genes involved in cholesterol efflux and sterol biosynthesis, respectively, transitioning to Nuclear Factor kappa-B (NF-κB) activation and Peroxisome Proliferator-Activated Receptor (PPAR) pathway modulation by 24 h. Co-expression network analysis prioritized functional modules intersecting with differentially expressed genes. We also performed untargeted metabolomics using cells treated with cholesterol for 6 h, which demonstrated extensive remodeling of lipid species. Interestingly, integrated transcriptomic and metabolic analysis uncovered GFPT1-driven Uridine Diphosphate-N-Acetylglucosamine (UDP-GlcNAc) accumulation and increased taurine levels. Validation experiments confirmed GFPT1 upregulation and ANGPTL4 downregulation through RT-qPCR and increased O-GlcNAcylation via Western blot. Importantly, clinical datasets further supported the correlations between GFPT1/ANGPTL4 expression and cholesterol levels in Non-Alcoholic Steatohepatitis (NASH) liver cancer patients. This work establishes a chronological paradigm of cholesterol sensing and identifies GFPT1 and ANGPTL4 as key regulators bridging glycosylation and lipid pathways, providing mechanistic insights into cholesterol-associated metabolic disorders. Full article

Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD), previously referred to as Non-Alcoholic Fatty Liver Disease (NAFLD), is a prevalent chronic liver condition strongly linked to Type 2 Diabetes Mellitus (T2DM) and obesity. Globally, MASLD is the most common cause of chronic liver disease. The bidirectional relationship between MASLD and T2DM underscores the pivotal role of insulin resistance in disease progression, which contributes to hepatic steatosis, oxidative stress, and inflammation, forming a vicious cycle. MASLD is also associated with heightened risks of cardiovascular and chronic kidney diseases, necessitating comprehensive treatment approaches. While lifestyle interventions and weight loss remain the cornerstone of management, their sustainability is challenging. This review highlights the evolving pharmacological landscape targeting MASLD and its advanced form, Metabolic Dysfunction-Associated Steatohepatitis (MASH). Currently, Resmetirom is the only FDA-approved drug for MASH. Current and investigational therapies, including insulin-sensitizing agents like peroxisome proliferator-activated receptor (PPAR) agonists, glucose-lowering drugs such as sodium-glucose co-transporter 2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor agonists (GLP-1 RA), drugs that target intermediary metabolism such as Vitamin E, de novo lipogenesis inhibitors, and emerging agents targeting the gut-liver axis and oxidative stress, are explored. These therapies demonstrate promising effects on hepatic steatosis, inflammation, and fibrosis, providing new avenues to address the multifaceted pathophysiology of MASLD. Full article

β-hydroxybutyrate (BHB) serves as an alternative cellular fuel during states of low glucose availability, such as fasting or carbohydrate restriction, when the body shifts to using fats and ketone bodies for energy. While BHB has shown potential metabolic benefits, its mechanisms of action in the context of obesity are not fully understood. In this study, we examined the effects of BHB supplementation on subcutaneous adipose tissue (SAT) metabolism in a diet-induced obesity (DIO) mouse model. Adult male mice were first fed a high-fat diet for six weeks, followed by a standard diet with or without BHB supplementation for an additional six weeks. BHB supplementation led to significant body weight loss independent of food intake. This weight reduction was associated with decreased adipocyte differentiation, reflected by reduced peroxisome proliferator-activated receptor gamma (PPARγ) protein levels and lower uncoupling protein 1 (UCP1) expression, indicating altered SAT function. Transcriptomic analysis of SAT revealed upregulation of genes involved in fatty acid activation and transport (e.g., Slc27a2, Plin5, Acot4, Acsm3, Rik). Functional enrichment highlighted the activation of the PPAR signaling pathway and enrichment of peroxisomal components in the BHB group. Together, these results suggest that BHB promotes lipid remodeling in SAT, enhancing fatty acid metabolism while suppressing thermogenic pathways, and thus may represent a novel mechanism contributing to adiposity reduction and metabolic improvement. Full article

Background/Objectives: Hexaraphane, also known as 6-methylsulfinylhexyl isothiocyanate, derived from wasabi (Eutrema japonicum), increases heme oxygenase-1 (HO-1) and aldehyde dehydrogenase 2 (ALDH2) mRNA expression by activating nuclear factor erythroid 2-related factor 2 (Nrf2) in both HepG2 cells and the mouse liver. Given the presence of a peroxisome proliferator-activated receptor (PPAR) response element (PPRE) in the HO-1 and ALDH2 promoters, the present study aimed to determine the effects of hexaraphane on PPARα-associated genes, age-related weight gain, plasma triglyceride levels, and hepatic senescence. Methods: HepG2 cells were treated with hexaraphane to evaluate PPARα target gene expression and PPRE transcriptional activity. Male C57BL/6J young control, aged control, and aged mice administered with hexaraphane for 16 weeks were assessed for food and water intake, body and tissue weights, plasma parameters, and hepatic PPARα-related gene expression. Results: Hexaraphane increased HO-1 mRNA expression levels in HepG2 cells, which was inhibited by GW6471, a PPARα antagonist. It elevated PPRE transcriptional activity and increased carnitine palmitoyltransferase 1A (CPT1A) mRNA expression levels, indicating PPARα activation. In aged mice, hexaraphane intake reduced body weight gain by decreasing the adipose tissue weight. Increased CPT1A expression levels and a tendency toward increased acyl-CoA oxidase 1 (ACOX1) expression levels in the liver of aged mice administered hexaraphane were associated with reduced plasma triglyceride levels and body weight gain. Increased hepatic Sirt1 expression levels in aged mice administered hexaraphane was associated with lower plasma triglyceride levels. Increased hepatic PPARα mRNA expression levels in aged mice administered hexaraphane suggest a positive feedback loop between PPARα and Sirt1. The expression levels of hepatic p21 mRNA, a senescence marker regulated by Sirt1, were upregulated in aged mice but suppressed by hexaraphane intake. Conclusions: Hexaraphane may prevent age-related body weight gain, elevated plasma triglyceride levels, and hepatic senescence by activating PPARα, potentially contributing to longevity. Full article

Obesity is a significant global health issue, profoundly affecting metabolic and cardiovascular health and other related chronic conditions. In Chile, the prevalence of obesity is among the highest within the Organisation for Economic Cooperation and Development (OECD) countries, highlighting a critical public health challenge. This narrative review examines current evidence on the independent and potential synergistic roles of omega-3 fatty acids and exercise in managing obesity-related metabolic dysfunction. Omega-3 fatty acids, particularly eicosapentaenoic acid (EPA), have been shown to lower triglyceride levels, enhance lipid metabolism, and modulate inflammation via pathways involving peroxisome proliferator-activated receptors (PPARs) and sterol regulatory element-binding protein-1c (SREBP-1c). Exercise interventions, such as moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT), provide distinct yet complementary metabolic benefits. Specifically, MICT improves body fat distribution and mitochondrial efficiency, whereas HIIT has notable effects on metabolic adaptability and insulin signaling. Additionally, emerging evidence points toward a potential role of the kinin-kallikrein system, particularly kallikrein 7 (KLK7), in obesity-associated insulin resistance. Despite these promising findings, several knowledge gaps persist regarding optimal dosing, intervention timing, population-specific effects, and the exact mechanisms behind the potential synergistic interactions between omega-3 supplementation and structured exercise. This review emphasizes the importance of conducting further research, particularly controlled clinical trials, to clarify these combined interventions’ effectiveness and establish targeted therapeutic strategies tailored to individual metabolic profiles. Full article

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a significant global public health issue. Luteolin possesses several beneficial biological properties, including antioxidation and anti-inflammation. This study investigated luteolin’s effect and potential mechanisms on MAFLD in high-fat diet (HFD)-fed rats. Rats were administered an HFD supplemented with fructose for 12 weeks to induce MAFLD. After that, the HFD-fed rats were given either luteolin (50 or 100 mg/kg/day) or metformin (100 mg/kg/day) for 4 weeks. Luteolin improved metabolic parameters induced by the HFD, since it decreased body weight, blood pressure, fasting blood glucose, serum insulin, free fatty acids, cholesterol, and triglyceride levels (p < 0.05). Luteolin reduced hepatic injury and inflammatory markers in HFD-fed rats (p < 0.05). Additionally, HFD-fed rats treated with luteolin showed reduced malondialdehyde and raised catalase activity in plasma (p < 0.05). Luteolin attenuated hepatic steatosis compared to the untreated rats (p < 0.05). Luteolin also increased plasma adiponectin levels accompanied by upregulation of adiponectin receptor 1 (AdipoR1), AMP-activated protein kinase (AMPK), and peroxisome proliferator-activated receptor γ (PPAR-γ) protein expression in liver (p < 0.05). These findings revealed that luteolin ameliorated HFD-induced MAFLD in rats, possibly by reducing metabolic alterations and oxidative stress and restoring AdipoR1, AMPK, and PPARγ protein expression in HFD-fed rats. Full article

Background/Objectives: Obesity is a significant global health concern, and the natural bioactive compounds with anti-obesity effects remain challenging. This study aims to examine the anti-obesity effect and the potential mechanism of Vaccinium oldhamii fruit water extract (VOW). Methods: Lipid accumulation, AMP-activated protein kinase (AMPK) activity, and Wnt/β-catenin signaling were evaluated in 3T3-L1 cells. In high-fat and high-sucrose diet (HFHSD)-induced obese mice, body weight, food intake, fat weight, serum lipid profiles, and adipogenic transcription factors were assessed. The most effective VOW fraction was selected by Oil Red O (ORO) staining and its mechanism was studied in 3T3-L1 cells. Results: VOW treatment significantly inhibited cellular lipid accumulation and suppressed phosphorylation of AMPK and its downstream protein, acetyl-CoA carboxylase (ACC). VOW also decreased adipogenic-associated protein expressions such as the peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding proteins α (C/EBP α), sterol regulatory element binding protein-1c (SREBP-1c), and fatty acid synthase (FAS). The enhanced effect of VOW was abolished by the knockdown of AMPK with siRNA. The inhibitory effect of VOW on differentiation depended on the treatment period, even though VOW treatment downregulated the C/EBP β expression at the early phase of differentiation. VOW dramatically reduced activation of AMPK, thereby downregulating adipogenic-associated proteins. Furthermore, the butanol fraction (BtOH) of VOW showed the most powerful effect of VOW dose-dependently reduced lipid accumulation by suppressing the phosphorylation of AMPK. Consistent with inhibited lipid accumulation in vitro, VOW reduced body weight and white adipose tissue weight in the HFHSD-induced obese animal model. Conclusions: Overall, our study suggested that the anti-adipogenesis effect of VOW and its BtOH fraction involved the activation of AMPK. Full article

Metabolic-dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is a highly prevalent metabolic disorder characterized by hepatic steatosis in conjunction with at least one cardiometabolic risk factor, such as obesity, type 2 diabetes, hypertension, or dyslipidemia. As global rates of obesity and metabolic syndrome continue to rise, MASLD is becoming a major public health concern, with projections indicating a substantial increase in prevalence over the coming decades. The disease spectrum ranges from simple steatosis to metabolic-dysfunction-associated steatohepatitis (MASH), fibrosis, cirrhosis, and hepatocellular carcinoma, contributing to significant morbidity and mortality worldwide. This review delves into the molecular mechanisms driving MASLD pathogenesis, including dysregulation of lipid metabolism, chronic inflammation, oxidative stress, mitochondrial dysfunction, and gut microbiota alterations. Recent advances in research have highlighted the role of genetic and epigenetic factors in disease progression, as well as novel therapeutic targets such as peroxisome proliferator-activated receptors (PPARs), fibroblast growth factors, and thyroid hormone receptor beta agonists. Given the multifaceted nature of MASLD, a multidisciplinary approach integrating early diagnosis, molecular insights, lifestyle interventions, and personalized therapies is critical. This review underscores the urgent need for continued research into innovative treatment strategies and precision medicine approaches to halt MASLD progression and improve patient outcomes. Full article

Cytokines are crucial in various physiological and pathological processes, especially in inflammatory diseases in mammals. However, the comprehensive identification of cytokines and their potential regulatory functions in the mammary glands of Holstein cows suffering from clinical mastitis (CM) remains only partially understood. This study aimed to systematically identify biological processes (BPs) and differentially expressed proteins (DEPs) associated with cytokines and to explore their functions through the analysis of previously obtained data from data-independent acquisition (DIA) proteomics. We confirmed that the dynamic balance between pro- and anti-inflammatory factors is closely associated with dairy mastitis. A total of 4 BPs, comprising 75 upregulated and 16 downregulated DEPs, were identified, particularly in relation to adiponectin (ADIPOQ), which strongly interacts with the other DEPs and participates in peroxisome proliferator-activated receptor (PPAR) and adipocytokine signaling pathways. Immunohistochemical and immunofluorescence staining revealed that ADIPOQ was predominantly localized in the cytoplasm of mammary epithelial cells. Moreover, the expression levels of ADIPOQ mRNA and protein in the mammary glands of the CM group were notably reduced compared to those in the healthy group. A potential mechanism of action of ADIPOQ was suggested, with findings indicating that a decrease in ADIPOQ expression could potentially worsen inflammation in CM. These results offer novel insights into cytokines and the regulatory mechanisms of ADIPOQ in Holstein cows with CM which may benefit the prevention and treatment of dairy mastitis. Full article

Pioglitazone (ACTOS) is a thiazolidinedione for peroxisome proliferator-activated receptor γ (PPAR-γ) that has been well established for the second or third line treatment of type 2 diabetes mellitus. Beyond the effects on glucose metabolism, pioglitazone displays positive effects on lipid metabolism, blood pressure, endothelial function, bone density, and apoptosis of cancer cells. In fact, according to in vitro experiments and preclinical studies, PPAR-γ ligand is currently considered a potential target for both chemoprevention and cancer therapy. PPAR-γ ligands are known to inhibit cancer cell proliferation and metastasis through terminal differentiation and underexpression of inflammatory mediators. Despite its anticancer properties, pioglitazone was withdrawn by the national medicine agencies of France and Germany, due to reports of increased incidence of bladder cancer. These reports were associated with European populations undergoing higher doses and longer durations of treatment. In this review, we discuss the pharmacokinetics, therapeutic potential, and limitations regarding the clinical use of pioglitazone, with a focus on cancer treatment. Full article

This review explores the promising potential of repurposing type 2 diabetes (T2D) medications for the treatment of Parkinson’s disease (PD), highlighting the shared pathophysiological mechanisms between these two age-related conditions, such as oxidative stress, mitochondrial dysfunction, and ferroptosis. The overlap suggests that existing diabetes drugs could target the common pathways involved in both conditions. Specifically, the review discusses how T2D medications, including metformin (Met), peroxisome-proliferator-activated receptor gamma (PPAR-γ) agonists, sodium-glucose cotransporter-2 (SGLT2) inhibitors, incretins, and dipeptidyl-peptidase 4 (DPP-4) inhibitors, can improve mitochondrial function, reduce neuroinflammation and oxidative stress, and potentially inhibit ferroptosis. The connection between ferroptosis and existing treatments, including diabetes medication, are only beginning to be explored. The limited data can be attributed also to the complexity of mechanisms involved in ferroptosis and Parkinson’s disease and to the fact that the specific role of ferroptosis in Parkinson’s disease pathogenesis has not been a primary focus until recent. Despite the promising preclinical evidence, clinical findings are mixed, underscoring the need for further research to elucidate these drugs’ roles in neurodegeneration. Repurposing existing diabetes medications that have well-established safety profiles for Parkinson’s disease treatment could significantly reduce the time and cost associated with drug development and could offer a more comprehensive approach to managing Parkinson’s disease compared to treatments targeting a single mechanism. Full article

The interpretation of the biochemistry of immune metabolism could be considered an attractive scientific field of biomedicine research. In this review, the role of glycolysis in macrophage polarization is discussed together with mitochondrial metabolism in cancer cells. In the first part, the focus is on the Warburg effect and redox metabolism during macrophage polarization, cancer development, and management of the immune response by the cancer cells. The second part addresses the possibility of impacts on the Warburg effect through targeting peroxisome proliferator-activated receptors (PPARs). This could be an activator of native immune responses. Because of the reported serious adverse effects of using synthetic ligands for PPARs in combination with chemotherapeutics, searches for less toxic and more active PPAR inhibitors, as well as blocking undesirable cellular PPAR-dependent processes, are in progress. On the other hand, recent research in modern immunotherapy has focused on the search for gentle immune-modulating natural compounds with harmless synergistic chemotherapeutic efficacy that can be used as an adjuvant. It is a well-known fact that the plant kingdom is a source of important therapeutic agents with multifaceted effectiveness. One of these is the known association with PPAR activities. In this regard, the secondary metabolites extracted from plants could change the game. Full article

Our previous study identified the apolipoprotein M (APOM) and cytochrome P450 family 7 subfamily A polypeptide 1 (CYP7A1) genes as candidates for milk traits in dairy cattle, which were significantly up-regulated in liver tissue of Holstein cows between the dry and lactation periods. The two genes play critical roles in the peroxisome proliferator-activated receptor (PPAR) pathway. In this study, we further confirmed whether the APOM and CYP7A1 genes had significant genetic impacts on milk production traits in a Chinese Holstein population. By dual-direction sequencing of the polymerase chain reaction (PCR) products of the complete coding sequences and 2000 bp of the 5′ and 3′ flanking regions on pooled DNA sample, seven and three single nucleotide polymorphisms (SNPs) were identified in APOM and CYP7A1, respectively. With SAS 9.2, phenotype-genotype association analysis revealed such SNPs were significantly associated with at least one of the milk production traits, including 305-day milk yield, milk fat yield, milk fat percentage, milk protein yield, and milk protein percentage in the first and second lactations (p = <0.01~0.04). With Haploview 4.2, we further found that six SNPs in APOM and thee SNPs in CYP7A1 formed one haplotype, respectively. The haplotypes were significantly associated with at least one of milk production traits as well (p = <0.01~0.02). Of note, we found the SNPs in the 5′ regulatory region, rs209293266 and rs110721287 in APOM and rs42765359 in CYP7A1, significantly impacted the gene transcriptional activity after mutation (p < 0.01) through changing the transcription factor binding sites by using luciferase assay experiments. Additionally, with RNAfold Web Server, rs110098953 and rs378530166 changed the mRNA secondary structures of APOM and CYP7A1 genes, respectively. In summary, our research is the first to demonstrate that APOM and CYP7A1 genes have significantly genetic effects on milk yield and composition traits, and the identified SNPs may serve as available genetic markers for genomic selection program in dairy cattle. Full article

Background/Objectives: Type 2 diabetes mellitus (T2DM) is considered a serious risk to public health since its prevalence is rapidly increasing worldwide despite numerous therapeutics. Insulin resistance in T2DM contributes to chronic inflammation and other metabolic abnormalities that generate fat accumulation in the liver, eventually leading to the progression of metabolic dysfunction-associated fatty liver disease (MAFLD). Recently, the possibility that microbial-derived metabolites may alleviate MAFLD through enterohepatic circulation has emerged, but the underlying mechanism remains unclear. In this research, we utilized metabolites obtained from the fermentation of guava leaf extract, which is well-known for its antidiabetic activity, to investigate their effects and mechanisms on MAFLD. Methods: Diabetes was induced by a high-fat diet and streptozotocin injection (80 mg/kg body weight) twice in mice. Subsequently, mice whose fasting blood glucose levels were measured higher than 300 mg/dL were administered with metabolites of Limosilactobacillus fermentum (LF) (50 mg/kg/day) or guava leaf extract fermented by L. fermentum (GFL) (50 mg/kg/day) by gavage for 15 weeks. Results: GFL supplementation mitigated hyperglycemia and hepatic insulin resistance. Moreover, GFL regulated abnormal hepatic histological changes and lipid profiles in diabetic mice. Furthermore, GFL enhanced energy metabolism by activating the sirtuin1 (SIRT1)/proliferator-activated receptor γ coactivator 1α (PGC1α)/peroxisome proliferator-activated receptor (PPAR)-α pathway in diabetic mice. Meanwhile, GFL supplementation suppressed hepatic inflammation in diabetic mice. Conclusions: Taken together, the current study elucidated that GFL could be a potential therapeutic to ameliorate hyperglycemia and hepatic steatosis by improving SIRT1/PGC-1α/ PPAR-α-related energy metabolism in T2DM. Full article

Menopause leads to a decline in estrogen levels, resulting in significant metabolic alterations that increase the risk of developing metabolic syndrome—a cluster of conditions including central obesity, insulin resistance, dyslipidemia, and hypertension. Traditional interventions such as hormone replacement therapy carry potential adverse effects, and lifestyle modifications alone may not suffice for all women. This review explores the potential role of palmitoylethanolamide (PEA), an endogenous fatty acid amide, in managing metabolic syndrome during the postmenopausal period. PEA primarily acts by activating peroxisome proliferator-activated receptor-alpha (PPAR-α), influencing lipid metabolism, energy homeostasis, and inflammation. Evidence indicates that PEA may promote the browning of white adipocytes, enhancing energy expenditure and reducing adiposity. It also improves lipid profiles by boosting fatty acid oxidation and decreasing lipid synthesis, potentially lowering low-density lipoprotein cholesterol and triglyceride levels while increasing high-density lipoprotein cholesterol. Additionally, the anti-inflammatory properties of PEA enhance insulin sensitivity by reducing pro-inflammatory cytokines that interfere with insulin signaling. PEA may aid in weight management by influencing appetite regulation and improving leptin sensitivity. Furthermore, its neuroprotective effects may address the mood disturbances and cognitive decline associated with menopause. Given these multifaceted biological activities and a favorable safety profile, PEA may represent a promising non-pharmacological supplement for managing metabolic syndrome in postmenopausal women. However, further large-scale clinical studies are necessary to establish its efficacy, optimal dosing, and long-term safety. If validated, PEA could become an integral part of strategies to improve metabolic and neuropsychological health outcomes in this population. Full article