Mitochondrial fatty acid oxidation in obesity

Adipocyte metabolic state regulates glial phagocytic function

Excess dietary sugar profoundly impacts organismal metabolism and health, yet it remains unclear how metabolic adaptations in adipose tissue influence other organs, including the brain. Here, we show that a high-sugar diet (HSD) in Drosophila reduces adipocyte glycolysis and mitochondrial pyruvate uptake, shifting metabolism toward fatty acid oxidation and ketogenesis. These metabolic changes trigger mitochondrial oxidation and elevate antioxidant responses. Adipocyte-specific manipulations of glycolysis, lipid metabolism, or mitochondrial dynamics non-autonomously modulate Draper expression in brain ensheathing glia, key cells responsible for neuronal debris clearance. Adipocyte-derived ApoB-containing lipoproteins maintain basal Draper levels in glia via LpR1, critical for effective glial phagocytic activity. Accordingly, reducing ApoB or LpR1 impairs glial clearance of degenerating neuronal debris after injury. Collectively, our findings demonstrate that dietary sugar-induced shifts in adipocyte metabolism substantially influence brain health by modulating glial phagocytosis, identifying adipocyte-derived ApoB lipoproteins as essential systemic mediators linking metabolic state with neuroprotective functions.

Effects of Tinospora cordifolia (giloy) on metabolic syndrome components: a mechanistic review

Metabolic syndrome is a cluster of some conditions such as high blood sugar, high blood triglycerides, low HDL cholesterol, abdominal obesity, and high blood pressure. Introducing a drug or a food that manages the majority of these medical conditions is invaluable. Tinospora cordifolia, known as guduchi and giloy, is a medicinal herb in ayurvedic medicine that is used in the treatment of various diseased conditions and also as a food for the maintenance of health. Here, we reviewed the current evidence supporting the role of giloy in the development and treatment of metabolic syndrome components. Appropriate articles that have been published until May 2024 were carefully extracted from PubMed, Scopus, and WOS databases to write a narrative review systematically. Gathered data showed the beneficial effects of giloy on metabolic syndrome components: hyperlipidemia, obesity, atherosclerosis, hypertension, and especially diabetes mellitus. As diabetes and insulin resistance seem to be a central feature of metabolic syndrome and in turn, can cause dyslipidemia, obesity, and, atherosclerosis, these beneficial effects are predictable with the anti-diabetogenic property of giloy. In this review, the main mechanisms of action of giloy in metabolic syndrome components are discussed. Based on the results, although giloy has been less investigated, considerable studies provide evidence of its beneficial effects on different components of metabolic syndrome. Relevant clinical trials are necessary to validate the mentioned effects, safety, and optimum dose of this herbal medicine and its components in managing different components of metabolic syndrome and transition from bench to bedside.

Histidine and soy isoflavones co-ingestion induces browning of white adipose tissue and promotes lipolysis in female rats

Beige adipocytes arise from white adipocytes in response to cold or other stimuli, known as browning of white adipose. Beige adipocytes play a role similar to that of brown adipocytes, express high levels of uncoupling protein 1 (UCP1), and are responsible for energy consumption via heat production, thus aiding in fat loss. Although histidine (His) and soy isoflavones (Iso) co-ingestion reportedly reduces food intake, body weight, and fat accumulation in female rats, the underlying mechanism remains unclear. Therefore, this study aimed to elucidate the mechanisms whereby histidine and soy isoflavones (His-Iso) co-ingestion suppresses fat accumulation. Female rats were fed a control diet or diet containing Iso, His, or His-Iso for 2 weeks, followed by sampling of periovarian white adipose tissue (poWAT) and retroperitoneal white adipose tissue (rWAT) and adipocyte morphology analysis. Additionally, the expression of browning- and lipid metabolism-related genes was examined. Histochemical analysis revealed the presence of multilocular lipid droplets, representative of beige adipocytes, in the poWAT and rWAT of rats in the His-Iso co-ingestion group. Quantitative PCR analysis showed that His-Iso co-ingestion upregulated brown adipocyte and beige adipocyte markers, including UCP1, indicating that His-Iso intake induces beige adipocytes. Moreover, His-Iso co-ingestion upregulated genes related to fatty acid oxidation (carnitine palmitoyl transferase 1A) and lipolysis (adipose triglyceride lipase) in WATs. In conclusion, His-Iso co-ingestion increases UCP1 expression and morphological changes to beige adipocytes, and suppresses fat accumulation by promotion of lipolysis and fatty acid oxidation in WAT.

High-Fat Diet and Altered Radiation Response

High-fat diets (HFDs) have become increasingly prevalent in modern societies, driving rising rates of obesity and metabolic syndrome. Concurrently, radiation exposure from medical treatments and environmental sources poses health risks shaped by both biological and environmental factors. This review explores the intersection between HFDs and radiation sensitivity/susceptibility, focusing on how diet-induced metabolic alterations influence the body's response to radiation. Evidence from preclinical and clinical studies indicates that HFDs significantly alter metabolism, leading to increased oxidative stress and immune system dysregulation. These metabolic changes can exacerbate radiation-induced oxidative stress, inflammation, and DNA damage, potentially increasing radiation sensitivity in normal tissues. Conversely, obesity and HFD-induced metabolic disruptions may activate cellular pathways involved in DNA repair, cell survival, and inflammatory responses, fostering tumor resistance and modifying the tumor microenvironment, which may impair the efficacy of radiation therapy in cancer treatment. Understanding the interplay between diet and radiation exposure is critical for optimizing public health guidelines and improving therapeutic outcomes. These findings underscore the need for further research into dietary interventions that may mitigate radiation-associated risks.

Butyrate: A potential mediator of obesity and microbiome via different mechanisms of actions

Butyrate, a short-chain fatty acid, is a crucial product of gut microbial fermentation with significant implications for various metabolic and physiological processes. Dietary sources of butyrate are limited, primarily derived from the fermentation of dietary fibers by butyrate-producing gut bacteria. Butyrate exerts its effects primarily as a histone deacetylase (HDAC) inhibitor and through signaling pathways involving G protein-coupled receptors (GPCRs). Its diverse benefits include promoting gut health, enhancing energy metabolism, and potentially alleviating complications associated with obesity. However, the exact role of butyrate in obesity is still under investigation, with a limited number of human trials necessitating further research to determine its efficacy and safety profile. Moreover, butyrate impact on the gut-brain axis and its modulation of microbiome effect on behavior highlight its broader importance in regulating host physiology. A thorough understanding of the metabolic pathways and mechanisms of butyrate is essential for developing targeted interventions for metabolic disorders. Continued research is crucial to fully realize its therapeutic potential and optimize its clinical applications in human health. In summary, this review illuminates the multifaceted role of butyrate as a potential mediator of obesity and related metabolic changes.

Distinct network patterns emerge from Cartesian and XOR epistasis models: a comparative network science analysis

BACKGROUND

Epistasis, the phenomenon where the effect of one gene (or variant) is masked or modified by one or more other genes, significantly contributes to the phenotypic variance of complex traits. Traditionally, epistasis has been modeled using the Cartesian epistatic model, a multiplicative approach based on standard statistical regression. However, a recent study investigating epistasis in obesity-related traits has identified potential limitations of the Cartesian epistatic model, revealing that it likely only detects a fraction of the genetic interactions occurring in natural systems. In contrast, the exclusive-or (XOR) epistatic model has shown promise in detecting a broader range of epistatic interactions and revealing more biologically relevant functions associated with interacting variants. To investigate whether the XOR epistatic model also forms distinct network structures compared to the Cartesian model, we applied network science to examine genetic interactions underlying body mass index (BMI) in rats (Rattus norvegicus).

RESULTS

Our comparative analysis of XOR and Cartesian epistatic models in rats reveals distinct topological characteristics. The XOR model exhibits enhanced sensitivity to epistatic interactions between the network communities found in the Cartesian epistatic network, facilitating the identification of novel trait-related biological functions via community-based enrichment analysis. Additionally, the XOR network features triangle network motifs, indicative of higher-order epistatic interactions. This research also evaluates the impact of linkage disequilibrium (LD)-based edge pruning on network-based epistasis analysis, finding that LD-based edge pruning may lead to increased network fragmentation, which may hinder the effectiveness of network analysis for the investigation of epistasis. We confirmed through network permutation analysis that most XOR and Cartesian epistatic networks derived from the data display distinct structural properties compared to randomly shuffled networks.

CONCLUSIONS

Collectively, these findings highlight the XOR model's ability to uncover meaningful biological associations and higher-order epistasis derived from lower-order network topologies. The introduction of community-based enrichment analysis and motif-based epistatic discovery emphasize network science as a critical approach for advancing epistasis research and understanding complex genetic architectures.

10-Gingerol reduces cytoplasmic lipid droplets and induces lipolysis in 3T3-L1 adipocytes

Obesity is a globally prevalent metabolic disorder characterized by an increased number of adipose cells and excessive fat in adipocytes. Herbal medicines, such as ginger, have shown potential in treating obesity by inhibiting adipogenesis and reducing adipocyte hypertrophy. Ginger contains bioactive compounds, particularly gingerols, which have demonstrated anti-adipogenic and/or lipolytic effects. However, research on the effects of 10-gingerol on adipose tissue remains limited. This study aimed to evaluate the effect of 10-gingerol on lipid content, lipolysis markers, and the expression of genes related to lipid metabolism in 3T3-L1 adipocytes. Three groups were analyzed: a negative control (preadipocytes), a positive control (mature adipocytes), and a group treated with 10-gingerol (10-G). Results showed that 10-G reduced lipid accumulation by 42.16% in mature adipocytes compared to the control, without affecting cell viability. Additionally, 10-G increased glycerol release and downregulated lipogenic genes such as Pparγ, Acaca, Fabp4, and Mtor, while upregulating genes related to fatty acid oxidation, including Cebpα, Cpt1a, Lipe, and Prkaa1. In conclusion, 10-gingerol reduces lipid content in mature adipocytes by downregulating lipogenesis, increasing lipolysis, and enhancing fatty acid oxidation.

Garcinol enriched fraction of Garcinia morella (Gaertn.) Desr. fruit rind improves gut health and reduces the risk of nonalcoholic fatty liver disease by regulating PCK1/ACC/SREBP1/FASn pathway in a mouse model

Nonalcoholic fatty liver disease (NAFLD), a fast-emerging global burden, is an umbrella term for several liver manifestations that result in excessive accumulation of fat in the liver. NAFLD leads to gut microbiome dysbiosis, loss in gut epithelia, increased gut permeability, etc. The limited availability of registered drugs for NAFLD highlights the urgent need to focus on understanding its pathogenesis and discovering new treatments, including the potential exploration of herbal therapies for managing the condition. In this study, we evaluated the bioactive potential of garcinol enriched fraction from Garcinia morella fruit rind in preventing NAFLD-associated increased gut permeability. Administration of garcinol-enriched fraction (GEF) significantly reduced body weight, serum lipids (triglyceride and total cholesterol) levels, and enzymes (alkaline phosphatase and aspartate aminotransferase) responsible for liver dysfunction in high-fat diet (HFD)-fed C57BL/6 mice. GEF treatment also regulated the alteration in signaling pathways of lipid metabolism in HFD-fed mice by inhibiting the overexpression of genes involved in de novo lipogenesis. Mice treated with GEF had increased gut microbial diversity, reduced pathogenic bacteria, and increased Lactococcus and Streptococcaceae genera. Additionally, GEF treatment could increase the expression of intestinal tight junction proteins, which were otherwise decreased in HFD-fed mice, stipulating its protective effect in maintaining gut barrier integrity. Our study demonstrated that GEF treatment reduces obesity in mice and improves gut health by keeping junctions tight and maintaining a healthy gut microbiome.

Chronobiological disruptions: unravelling the interplay of shift work, circadian rhythms, and vascular health in the context of stroke risk

Shift work, particularly night shifts, disrupts circadian rhythms and increases stroke risk. This manuscript explores the mechanisms connecting shift work with stroke, focusing on circadian rhythms, hypertension, and diabetes. The circadian system, controlled by different mechanisms including central and peripheral clock genes, suprachiasmatic nuclei (SCN), and pineal gland (through melatonin production), regulates body functions and responds to environmental signals. Disruptions in this system affect endothelial cells, leading to blood pressure issues. Type 2 diabetes mellitus (T2DM) is significantly associated with night shifts, with circadian disturbances affecting glucose metabolism, insulin sensitivity, and hormone regulation. The manuscript examines the relationship between melatonin, insulin, and glucose balance, highlighting pathways that link T2DM to stroke risk. Additionally, dyslipidemia, particularly reduced HDL-c levels, results from shift work and contributes to stroke development. High lipid levels cause oxidative stress, inflammation, and endothelial dysfunction, increasing cerebrovascular risks. The manuscript details the effects of dyslipidemia on brain functions, including disruptions in blood flow, blood-brain barrier integrity, and neural cell death. This comprehensive analysis emphasizes the complex interplay of circadian disruption, hypertension, diabetes, and dyslipidemia in increasing stroke risk among shift workers. Understanding these mechanisms is essential for developing targeted interventions to reduce stroke susceptibility and improve cerebrovascular health in this vulnerable population.

Relationship between systemic biomarker of lipid peroxidation 4-hydroxynonenal and lipidomic profile of morbidly obese patients undergoing bariatric surgery

Obesity is characterized by fat accumulation, impaired metabolism and oxidative stress, frequently associated with lipid peroxidation and generation of bioactive 4-hydroxynonenal (4-HNE). This study aimed to evaluate the impact of bariatric surgery-induced weight loss on lipid peroxidation and associated perturbations in lipid profile. Plasma samples of twenty obese individuals before and 6 months after bariatric surgery were collected in addition to samples of ten healthy controls. HILIC-LC-MS/MS platform was used to characterize phospholipid profile, while lipid peroxidation markers 15-F2t-IsoP, 10-F4t-NeuroP and reactive aldehyde 4-HNE were quantified by RP-LC-MS/MS and GC-MS, respectively. Six months post-surgery lipid peroxidation markers decreased significantly and the BMI of morbidly obese patients decreased by 13 on average. Lipidomics analysis, identified 117 phospholipid species from seven classes, and showed obesity-associated lipidome perturbations, particularly in ether-linked phosphatidylethanolamines (PEo). A total of 45 lipid species were found to be significantly altered with obesity, while 10 lipid species correlated with lipid peroxidation markers. Sample pairwise analyses indicated an interesting link between 4-HNE and the amount of two PEos, PEo (38:2) and PEo (36:2). The results indicate that weight loss-induced improvement of redox homeostasis together with changes in lipid metabolites may serve as markers of metabolic improvement. However, further studies are needed to understand the role of obesity-induced oxidative stress on ether lipid biosynthesis and lipidome perturbations, as well as the impact of bariatric surgery on metabolic improvement.

Lactobacillus paracasei subsp. paracasei NTU 101 prevents obesity by regulating AMPK pathways and gut microbiota in obese rat

This study assessed the anti-obesity effects of Lactobacillus paracasei subsp. paracasei NTU 101 (NTU 101) both in vitro and in vivo. Initially, the cytotoxicity and lipid accumulation inhibitory effects of NTU 101 on 3T3-L1 cells were evaluated using the MTT assay and oil red O assay, respectively. Subsequently, the anti-obesity effects of NTU 101 were investigated in high-fat diet-induced obese rat. Moreover, western blotting was performed to measure the obesity-related protein expression of PPARα, PPARβ, PPARγ, C/EBPα, C/EBPβ, ATGL, p-p38 MAPK, p-ERK1/2, p-AMPK and CPT-1 in both 3T3-L1 adipocytes and adipose and liver tissues. Treatment with 16 × 108 CFU/mL NTU 101 reduced lipid accumulation in 3T3-L1 adipocytes by more than 50 %. Oral administration of NTU 101 significantly attenuated body weight gain, as well as adipose tissue weight. NTU 101 administration enhanced fatty acid oxidation increasing expression levels of PPARα, CPT-1, and p-AMPK proteins in liver tissue, while simultaneously inhibited adipogenesis by reducing PPARγ and C/EBPα proteins in adipose tissue. Furthermore, NTU 101 supplementation positively modulated the composition of gut microbiota, notably increasing the abundance of Akkermansiaceae. This present study suggests that NTU 101 exerts anti-obesity effects by regulating gut microbiota, fatty acid oxidation, lipolysis and adipogenesis.

Specific small interfering RNAs (siRNAs) for targeting the metastasis, immune responses, and drug resistance of colorectal cancer cells (CRC)

Colorectal cancer (CRC) involves various genetic alterations, with liver metastasis posing a significant clinical challenge. Furthermore, CRC cells mostly show an increase in resistance to traditional treatments like chemotherapy. It is essential to investigate more advanced and effective therapies to prevent medication resistance and metastases and extend patient life. As a result, it is anticipated that small interfering RNAs (siRNAs) would be exceptional instruments that can control gene expression by RNA interference (RNAi). In eukaryotes, RNAi is a biological mechanism that destroys specific messenger RNA (mRNA) molecules, thereby inhibiting gene expression. In the management of CRC, this method of treatment represents a potential therapeutic agent. However, it is important to acknowledge that siRNA therapies have significant issues, such as low serum stability and nonspecific absorption into biological systems. Delivery mechanisms are thus being created to address these issues. In the current work, we address the potential benefits of siRNA therapy and outline the difficulties in treating CRCby focusing on the primary signaling pathways linked to metastasis as well as genes implicated in the multi-drug resistance (MDR) process.

Adipocyte metabolic state regulates glial phagocytic function

Obesity and type 2 diabetes are well-established risk factors for neurodegenerative disorders1-4, yet the underlying mechanisms remain poorly understood. The adipocyte-brain axis is crucial for brain function, as adipocytes secrete signaling molecules, including lipids and adipokines, that impinge on neural circuits to regulate feeding and energy expenditure5. Disruptions in the adipocyte-brain axis are associated with neurodegenerative conditions6, but the causal links are not fully understood. Neural debris accumulates with age and injury, and glial phagocytic function is crucial for clearing this debris and maintaining a healthy brain microenvironment7-9. Using adult Drosophila, we investigate how adipocyte metabolism influences glial phagocytic activity in the brain. We demonstrate that a prolonged obesogenic diet increases adipocyte fatty acid oxidation and ketogenesis. Genetic manipulations that mimic obesogenic diet-induced changes in adipocyte lipid and mitochondrial metabolism unexpectedly reduce the expression of the phagocytic receptor Draper in Drosophila microglia-like cells in the brain. We identify Apolpp-the Drosophila equivalent of human apolipoprotein B (ApoB)-as a critical adipocyte-derived signal that regulates glial phagocytosis. Additionally, we show that Lipoprotein Receptor 1 (LpR1), the LDL receptor on phagocytic glia, is required for glial capacity to clear injury-induced neuronal debris. Our findings establish that adipocyte-brain lipoprotein signaling regulates glial phagocytic function, revealing a novel pathway that links adipocyte metabolic disorders with neurodegeneration.

Evaluating the Nutritional Composition of Unripe Citrus and Its Effect on Inhibiting Adipogenesis and Adipocyte Differentiation

Citrus fruits offer a range of health benefits due to their rich nutritional profile, including vitamin C, flavonoids, carotenoids, and fiber. It is known that unripe citrus has higher levels of vitamin C, dietary fiber, polyphenols, and flavonoids compared to mature fruits. In this study, we assessed the nutritional components of unripe citrus peel and pressed juices, as well as their anti-obesity potential through the modulation of adipocyte differentiation and the expression of adipogenesis-related genes, specifically PPARγ and C/EBPα, in 3T3-L1 preadipocytes. Our analysis revealed that unripe citrus peel exhibited elevated levels of fiber and protein compared to pressed juice, with markedly low levels of free sugar, particularly sucrose. The content of hesperidin, a representative flavonoid in citrus fruits, was 3,157.6 mg/kg in unripe citrus peel and 455.5 mg/kg in pressed juice, indicating that it was approximately seven times higher in unripe citrus peel compared to pressed juice. Moreover, we observed that the peel had a dose-dependently inhibitory effect on adipocyte differentiation, which was linked to a significant downregulation of adipogenesis-related gene expression. Thus, our findings suggest that unripe citrus possesses anti-obesity effects by impeding adipogenesis and adipocyte differentiation, with the peel demonstrating a more pronounced effect compared to pressed juice.

The long non-coding RNAs (lncRNA) in the pathogenesis of gastric cancer cells: molecular mechanisms and involvement miRNAs

A complex sequence of occurrences, including host genetic vulnerability, Helicobacter pylori infection, and other environmental variables, culminate in gastric cancer (GC). The development of several genetic and epigenetic changes in oncogenes and tumor suppressor genes causes dysregulation of several signaling pathways, which upsets the cell cycle and the equilibrium between cell division and apoptosis, leading to GC. Developments in computational biology and RNA-seq technology enable quick detection and characterization of long non-coding RNAs (lncRNAs). Recent studies have shown that long non-coding RNAs (lncRNAs) have multiple roles in the development of gastric cancer. These lncRNAs interact with molecules of protein, RNA, DNA, and/or combinations. This review article explores several gastric cancer-associated lncRNAs, such as ADAMTS9-AS2, UCA1, XBP-1, and LINC00152. These various lncRNAs could change GC cell apoptosis, migration, and invasion features in the tumor microenvironment. This review provides an overview of the most recent research on lncRNAs and GC cell apoptosis, migration, invasion, and drug resistance, focusing on studies conducted in cancer cells and healthy cells during differentiation.

The role of lipid droplet associated proteins in inherited human disorders

Proteins which associate with the surface of lipid droplets are intimately involved in the regulation of the droplets. Several human inherited disorders have now been linked to loss- and, in some cases, likely gain-of-function mutations in the genes encoding these proteins. These are summarised in this Graphical Review.

Magnolia officinalis Rehder & E. Wilson ameliorates white adipogenesis by upregulating AMPK and SIRT1 in vitro and in vivo

Although there is an established link between Magnolia Cortex (MO) and lipid metabolism in previous research, its exploration within the context of obesity has been limited. Therefore, the present study investigated the therapeutic effects of MO on obesity and its mechanism of action in vitro and in vivo. Our chromatography analysis revealed that Honokiol and Magnolol are contained in MO extract. In vitro experiments showed that lipid droplets, adipogenic, and lipogenic genes were notably diminished by increasing sirtuin 1 (SIRT1) and AMP-activated kinase (AMPK) protein expression in MO-treated 3T3-L1 adipocytes. In vivo experiments exhibited that MO administration significantly recovered the adipogenesis, lipogenesis, and fatty acid oxidation genes by increasing the SIRT1 and AMPK expression in white adipose tissue. Furthermore, hepatic steatosis by HFD feeding was ameliorated in MO-administered obese mice. We conclude that MO could be important manager for treating obesity through AMPK and SIRT1 regulation.

An Update on the Role and Potential Molecules in Relation to Ruminococcus gnavus in Inflammatory Bowel Disease, Obesity and Diabetes Mellitus

Ruminococcus gnavus (R. gnavus) is a gram-positive anaerobe commonly resides in the human gut microbiota. The advent of metagenomics has linked R. gnavus with various diseases, including inflammatory bowel disease (IBD), obesity, and diabetes mellitus (DM), which has become a growing area of investigation. The initial focus of research primarily centered on assessing the abundance of R. gnavus and its potential association with disease presentation, taking into account variations in sample size, sequencing and analysis methods. However, recent investigations have shifted towards elucidating the underlying mechanistic pathways through which R. gnavus may contribute to disease manifestation. In this comprehensive review, we aim to provide an updated synthesis of the current literature on R. gnavus in the context of IBD, obesity, and DM. We critically analyze relevant studies and summarize the potential molecular mediators implicated in the association between R. gnavus and these diseases. Across numerous studies, various molecules such as methylation-controlled J (MCJ), glucopolysaccharides, ursodeoxycholic acid (UDCA), interleukin(IL)-10, IL-17, and capric acid have been proposed as potential contributors to the link between R. gnavus and IBD. Similarly, in the realm of obesity, molecules such as hydrogen peroxide, butyrate, and UDCA have been suggested as potential mediators, while glycine ursodeoxycholic acid (GUDCA) has been implicated in the connection between R. gnavus and DM. Furthermore, it is imperative to emphasize the necessity for additional studies to evaluate the potential efficacy of targeting pathways associated with R. gnavus as a viable strategy for managing these diseases. These findings have significantly expanded our understanding of the functional role of R. gnavus in the context of IBD, obesity, and DM. This review aims to offer updated insights into the role and potential mechanisms of R. gnavus, as well as potential strategies for the treatment of these diseases.

Pennogenin 3-O-β-Chacotrioside Attenuates Hypertrophied Lipid Accumulation by Enhancing Mitochondrial Oxidative Capacity

Excessive lipid accumulation in adipocytes is a primary contributor to the development of metabolic disorders, including obesity. The consumption of bioactive compounds derived from natural sources has been recognized as being safe and effective in preventing and alleviating obesity. Therefore, we aimed to explore the antilipidemic effects of pennogenin 3-O-β-chacotrioside (P3C), a steroid glycoside, on hypertrophied 3T3-L1 adipocytes. Oil Red O and Nile red staining demonstrated a P3C-induced reduction in lipid droplet accumulation. Additionally, the increased expression of adipogenic and lipogenic factors, including PPARγ and C/EBPα, during the differentiation process was significantly decreased by P3C treatment at both the protein and mRNA levels. Furthermore, P3C treatment upregulated the expression of fatty acid oxidation-related genes such as PGC1α and CPT1a. Moreover, mitochondrial respiration and ATP generation increased following P3C treatment, as determined using the Seahorse XF analyzer. P3C treatment also increased the protein expression of mitochondrial oxidative phosphorylation in hypertrophied adipocytes. Our findings suggest that P3C could serve as a natural lipid-lowering agent, reducing lipogenesis and enhancing mitochondrial oxidative capacity. Therefore, P3C may be a promising candidate as a therapeutic agent for obesity-related diseases.

Oxidative Stress in Postbariatric Patients: A Systematic Literature Review Exploring the Long-term Effects of Bariatric Surgery

Background

The present study investigates the impact of oxidative stress after bariatric surgery in patients with obesity. This field of study has gained great interest in recent years due to the role that oxidative stress plays in metabolic diseases. Obesity, by itself, can generate an increase in reactive oxygen and nitrogen species, intensifying cellular damage and promoting the progression of adverse metabolic conditions. In this context, bariatric surgery emerges as a candidate capable of modifying oxidative stress biomarkers, facilitating the patient's metabolic recovery.

Methods

A systematic review was carried out, identifying 30 studies found in databases such as PubMed, Scopus, Web of Science, and Google Scholar. It looked at the link between oxidative stress and recovery after bariatric surgery in patients. The selection of studies was based on the measurement of oxidative stress biomarkers before and after surgical intervention.

Results

The results reveal a significant decrease in oxidative stress biomarkers after bariatric surgery. However, a notable variability in antioxidant activity is observed between different patients, as well as a significant influence of comorbidities.

Conclusions

Bariatric surgery is postulated as an effective intervention in reducing oxidative stress in patients with obesity, enhancing antioxidant activity and improving patient recovery. This finding highlights the importance of considering oxidative stress management as an integral part of postoperative care, suggesting the need to implement complementary treatment strategies to optimize health outcomes.

Effect of YC-1102 on the Improvement of Obesity in High-Fat Diet-Induced Obese Mice

Obesity is one of the major risk factors for metabolic diseases worldwide. This study examined the effects of YC-1102, an extract derived from the roots of Rosa multiflora, on 3T3-L1 preadipocytes and high-fat diet (HFD)-induced obese mice. In vivo experiments involved the oral administration of YC-1102 (100, 150, and 200 mg/kg body weight) daily to mice for eight weeks. YC-1102 was found to downregulate the expressions of PPARγ and C/EBPα during adipogenesis, inhibiting adipocyte differentiation and upregulating the expression of PGC-1α for energy metabolism to enhance mitochondrial biogenesis and fatty acid oxidation. It has been shown that daily administration of YC-1102 to mice receiving a HFD prevented an increase in body weight and the accumulation of body fat. YC-1102 administration also reduced TG, TC, and LDL cholesterol levels, as well as glucose and leptin levels, and increased adiponectin levels, thus effectively inhibiting the metabolism of lipids. YC-1102-treated mice showed significant reductions in the mRNA expression of PPARγ and C/EBPα. The levels of PGC-1α involved in energy metabolism increased significantly in the YC-1102-treated mice when compared to the HFD-treated mice. According to the findings of this study, YC-1102 has a dual mechanism that reduces transcription factors that promote the differentiation of adipocytes and increases transcription factors that promote energy consumption.

The obesity-autophagy-cancer axis: Mechanistic insights and therapeutic perspectives

Autophagy, a self-degradative process vital for cellular homeostasis, plays a significant role in adipose tissue metabolism and tumorigenesis. This review aims to elucidate the complex interplay between autophagy, obesity, and cancer development, with a specific emphasis on how obesity-driven changes affect the regulation of autophagy and subsequent implications for cancer risk. The burgeoning epidemic of obesity underscores the relevance of this research, particularly given the established links between obesity, autophagy, and various cancers. Our exploration delves into hormonal influence, notably INS (insulin) and LEP (leptin), on obesity and autophagy interactions. Further, we draw attention to the latest findings on molecular factors linking obesity to cancer, including hormonal changes, altered metabolism, and secretory autophagy. We posit that targeting autophagy modulation may offer a potent therapeutic approach for obesity-associated cancer, pointing to promising advancements in nanocarrier-based targeted therapies for autophagy modulation. However, we also recognize the challenges inherent to these approaches, particularly concerning their precision, control, and the dual roles autophagy can play in cancer. Future research directions include identifying novel biomarkers, refining targeted therapies, and harmonizing these approaches with precision medicine principles, thereby contributing to a more personalized, effective treatment paradigm for obesity-mediated cancer.

Unravelling the Influence of Endocrine-Disrupting Chemicals on Obesity Pathophysiology Pathways

Obesity represents a global health concern, affecting individuals of all age groups across the world. The prevalence of excess weight and obesity has escalated to pandemic proportions, leading to a substantial increase in the incidence of various comorbidities, such as cardiovascular diseases, type 2 diabetes, and cancer. This chapter seeks to provide a comprehensive exploration of the pathways through which endocrine-disrupting chemicals can influence the pathophysiology of obesity. These mechanisms encompass aspects such as the regulation of food intake and appetite, intestinal fat absorption, lipid metabolism, and the modulation of inflammation. This knowledge may help to elucidate the role of exogenous molecules in both the aetiology and progression of obesity.

Circulating level of β-aminoisobutyric acid (BAIBA), a novel myokine-like molecule, is inversely associated with fat mass in patients with heart failure

Results of experimental studies have shown that β-aminoisobutyric acid (BAIBA), an exercise-induced myokine-like molecule, is an endogenous negative regulator of fat mass in mice, but it remains unclear whether that is the case in humans, though an enhanced BAIBA concentration in patients receiving sodium-glucose cotransporter 2 inhibitors was found in our recent study. The objective of this study was to analyze the determinants of circulating BAIBA concentration in humans, with focus on the possible link between circulating BAIBA and body composition including fat mass. Data for 188 consecutive patients with heart failure (HF, 64 ± 13 years; 70% male) who received a dual energy X ray absorptiometry (DEXA) scan for assessment of body composition including fat mass index (FMI) and appendicular skeletal muscle mass index (ASMI) were used in this study. Plasma BAIBA concentration in a fasting state after stabilization of HF was determined using ultraperformance liquid chromatography. Plasma BAIBA was detected in 66% of the patients. In simple linear regression analyses of data from patients in whom plasma BAIBA was detected, plasma BAIBA concentration was positively correlated with uric acid and was negatively correlated with body mass index (BMI), estimated glomerular filtration rate (eGFR), FMI, and % body fat. There were no correlations between plasma BAIBA concentration and indexes of muscle mass and bone mass. The results of multiple linear regression analyses showed that FMI and % body fat in addition to BMI, but not ASMI, were independent explanatory factors for plasma BAIBA concentration. In conclusion, plasma BAIBA concentration is inversely correlated with indexes of fat mass, indicating that BAIBA may be a therapeutic target for excessive fat accumulation.

Targeting metabolic reprogramming in hepatocellular carcinoma to overcome therapeutic resistance: A comprehensive review

Hepatocellular carcinoma (HCC) poses a heavy burden on human health with high morbidity and mortality rates. Systematic therapy is crucial for advanced and mid-term HCC, but faces a significant challenge from therapeutic resistance, weakening drug effectiveness. Metabolic reprogramming has gained attention as a key contributor to therapeutic resistance. Cells change their metabolism to meet energy demands, adapt to growth needs, or resist environmental pressures. Understanding key enzyme expression patterns and metabolic pathway interactions is vital to comprehend HCC occurrence, development, and treatment resistance. Exploring metabolic enzyme reprogramming and pathways is essential to identify breakthrough points for HCC treatment. Targeting metabolic enzymes with inhibitors is key to addressing these points. Inhibitors, combined with systemic therapeutic drugs, can alleviate resistance, prolong overall survival for advanced HCC, and offer mid-term HCC patients a chance for radical resection. Advances in metabolic research methods, from genomics to metabolomics and cells to organoids, help build the HCC metabolic reprogramming network. Recent progress in biomaterials and nanotechnology impacts drug targeting and effectiveness, providing new solutions for systemic therapeutic drug resistance. This review focuses on metabolic enzyme changes, pathway interactions, enzyme inhibitors, research methods, and drug delivery targeting metabolic reprogramming, offering valuable references for metabolic approaches to HCC treatment.

Loss of the centrosomal protein ALMS1 alters lipid metabolism and the regulation of extracellular matrix-related processes

BACKGROUND

Alström syndrome (ALMS) is a rare autosomal recessive disease that is associated with mutations in ALMS1 gene. The main clinical manifestations of ALMS are retinal dystrophy, obesity, type 2 diabetes mellitus, dilated cardiomyopathy and multi-organ fibrosis, characteristic in kidneys and liver. Depletion of the protein encoded by ALMS1 has been associated with the alteration of different processes regulated via the primary cilium, such as the NOTCH or TGF-β signalling pathways. However, the cellular impact of these deregulated pathways in the absence of ALMS1 remains unknown.

METHODS

In this study, we integrated RNA-seq and proteomic analysis to determine the gene expression profile of hTERT-BJ-5ta ALMS1 knockout fibroblasts after TGF-β stimulation. In addition, we studied alterations in cross-signalling between the TGF-β pathway and the AKT pathway in this cell line.

RESULTS

We found that ALMS1 depletion affects the TGF-β pathway and its cross-signalling with other pathways such as PI3K/AKT, EGFR1 or p53. In addition, alterations associated with ALMS1 depletion clustered around the processes of extracellular matrix regulation and lipid metabolism in both the transcriptome and proteome. By studying the enriched pathways of common genes differentially expressed in the transcriptome and proteome, collagen fibril organisation, β-oxidation of fatty acids and eicosanoid metabolism emerged as key processes altered by the absence of ALMS1. Finally, an overactivation of the AKT pathway was determined in the absence of ALMS1 that could be explained by a decrease in PTEN gene expression.

CONCLUSION

ALMS1 deficiency disrupts cross-signalling between the TGF-β pathway and other dependent pathways in hTERT-BJ-5ta cells. Furthermore, altered cross-signalling impacts the regulation of extracellular matrix-related processes and fatty acid metabolism, and leads to over-activation of the AKT pathway.

Erchen Decoction alleviates obesity-related hepatic steatosis via modulating gut microbiota-drived butyric acid contents and promoting fatty acid β-oxidation

ETHNOPHARMACOLOGICAL RELEVANCE

Erchen decoction (ECD) is a traditional Chinese medicine formula comprising six distinct herbs and has been documented to possess a protective effect against obesity. The study conducted previously demonstrated that ECD has the potential to effectively modulate the composition of gut microbiota and levels of short-chain fatty acids (SCFAs) in obese rat. However, the regulatory mechanism of ECD on gut microbiota and SCFAs and further improvement of obesity have not been thoroughly explained.

AIM OF THE STUDY

The objective of this study was to examine the therapeutic effect and molecular mechanism of ECD in a rat model of high-fat diet (HFD) feeding.

MATERIALS AND METHODS

Rats with HFD-induced obesity were treated with ECD. Upon completion of the study, serum and liver samples were procured to conduct biochemical, pathological, and Western blotting analyses. The investigation of alterations in the gut microbiota subsequent to ECD treatment was conducted through the utilization of 16S rRNA sequencing. The metabolic alterations in the cecal contents were examined through the utilization of mass spectrometry-ultraperformance liquid chromatography.

RESULTS

ECD treatment improved lipid metabolic disorders and reduced hepatic steatosis in HFD-induced obese rats. Obese rat treated with ECD showed a higher abundance of SCFA-producing bacteria, including Lactobacillus, Bifidobacterium, and Butyricicoccus, and lower abundance of disease-related bacteria, such as Bacteroides, Parabacteroides, and Sediminibacterium. Additionally, ECD caused an increase in total SCFAs levels; in particular, butyric acid was dramatically increased in the HFD group. Rats treated with ECD also exhibited significantly increased butyric acid concentrations in the serum and liver. The subsequent reduction in histone deacetylase 1 expression and increase in acetyl-histone 3-lysine 9 (H3K9ac) levels contributed to the promotion of fatty acid β-oxidation (FAO) in liver by ECD.

CONCLUSION

This study demonstrates that ECD regulates the gut microbiota and promotes butyric acid production to ameliorate obesity-related hepatic steatosis. The mechanism might be related to the promotion of FAO via a butyric acid-mediated increase in H3K9ac levels in the liver.

Anti-obesity effect of Lythri herba water extracts in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Lythrum salicaria L., also called purple loosestrife, has traditionally been used as a medicinal plant to treat internal dysfunction, such as gastrointestinal disorders or hemorrhages. It contains numerous phytochemical compounds, including orientin, and has been reported to have anti-diarrheal, anti-inflammatory, antioxidant, and antimicrobial properties.

AIM OF THE STUDY

The effects of Lythrum salicaria L. on obesity have not been explored. Therefore, we investigated the anti-obesity effects of Lythri Herba, the aerial part of this plant, in vitro and in vivo.

MATERIALS AND METHODS

Using distilled water, Lythri Herba water extracts (LHWE) were prepared by extracting Lythri Herba at 100°Ϲ. The contents of orientin in LHWE were identified using High Performance Liquid Chromatography (HPLC) analysis. To evaluate the anti-obesity effect of LHWE, 3T3-L1 adipocytes and a high-fat diet (HFD)-fed mice were used. Oil-red O staining was performed to examine the anti-adipogenic effects of LHWE in vitro. The histological changes in epididymal white adipose tissue (epiWAT) by LHWE were examined using hematoxylin and eosin staining. Serum leptin levels were measured by enzyme-linked immunosorbent assay. Specific quantification kits measured total cholesterol and triglyceride levels in the serum. The relative fold induction of protein and mRNA was determined using western blot and Quantitative real-time Polymerase Chain Reaction analysis, respectively.

RESULTS

HPLC analysis demonstrated the presence of orientin in LHWE. LHWE treatment markedly reduced lipid accumulation in differentiated 3T3-L1 adipocytes. LHWE administration also conferred resistance to HFD-induced weight gain in mice and reduced epiWAT mass. Mechanistically, LHWE significantly decreased lipogenesis by downregulating lipoprotein lipase (LPL), glucose-6-phosphate dehydrogenase, ATP-citrate lyase, fatty acid synthase, stearoyl-CoA desaturase 1, sterol regulatory element binding transcription factor 1, and carbohydrate response element binding protein expression and increased the expression of genes involved in fatty acid oxidation (FAO), peroxisome proliferator-activated receptor α and carnitine palmitoyltransferase 1 in 3T3-L1 adipocytes and epiWAT. Furthermore, LHWE significantly up-regulated the phosphorylation of AMP-activated protein kinase in 3T3-L1 adipocytes and epiWAT.

CONCLUSION

LHWE decreases white adipogenesis in vitro and HFD-induced weight gain in vivo, which is associated with reduced lipogenesis and enhanced FAO.

Fatty acid oxidation regulates cellular senescence by modulating the autophagy-SIRT1 axis

Senescence, a cellular process through which damaged or dysfunctional cells suppress the cell cycle, contributes to aging or age-related functional decline. Cell metabolism has been closely correlated with aging processes, and it has been widely recognized that metabolic changes underlie the cellular alterations that occur with aging. Here, we report that fatty acid oxidation (FAO) serves as a critical regulator of cellular senescence and uncover the underlying mechanism by which FAO inhibition induces senescence. Pharmacological or genetic ablation of FAO results in a p53-dependent induction of cellular senescence in human fibroblasts, whereas enhancing FAO suppresses replicative senescence. We found that FAO inhibition promotes cellular senescence through acetyl-CoA, independent of energy depletion. Mechanistically, increased formation of autophagosomes following FAO inhibition leads to a reduction in SIRT1 protein levels, thereby contributing to senescence induction. Finally, we found that inhibition of autophagy or enforced expression of SIRT1 can rescue the induction of senescence as a result of FAO inhibition. Collectively, our study reveals a distinctive role for the FAO-autophagy-SIRT1 axis in the regulation of cellular senescence. [BMB Reports 2023; 56(12): 651-656].

Fatty acid oxidation regulates cellular senescence by modulating the autophagy-SIRT1 axis

Senescence, a cellular process through which damaged or dysfunctional cells suppress the cell cycle, contributes to aging or age-related functional decline. Cell metabolism has been closely correlated with aging processes, and it has been widely recognized that metabolic changes underlie the cellular alterations that occur with aging. Here, we report that fatty acid oxidation (FAO) serves as a critical regulator of cellular senescence and uncover the underlying mechanism by which FAO inhibition induces senescence. Pharmacological or genetic ablation of FAO results in a p53-dependent induction of cellular senescence in human fibroblasts, whereas enhancing FAO suppresses replicative senescence. We found that FAO inhibition promotes cellular senescence through acetyl-CoA, independent of energy depletion. Mechanistically, increased formation of autophagosomes following FAO inhibition leads to a reduction in SIRT1 protein levels, thereby contributing to senescence induction. Finally, we found that inhibition of autophagy or enforced expression of SIRT1 can rescue the induction of senescence as a result of FAO inhibition. Collectively, our study reveals a distinctive role for the FAO-autophagy-SIRT1 axis in the regulation of cellular senescence. [BMB Reports 2023; 56(12): 651-656].

Effect of herbal extracts and Saroglitazar on high-fat diet-induced obesity, insulin resistance, dyslipidemia, and hepatic lipidome in C57BL/6J mice

We evaluated the effects of select herbal extracts (Tinospora cordifolia [TC], Tinospora cordifolia with Piper longum [TC + PL], Withania somnifera [WS], Glycyrrhiza glabra [GG], AYUSH-64 [AY-64], and Saroglitazar [S]) on various parameters in a diet-induced obesity mouse model. After 12 weeks of oral administration of the herbal extracts in high-fat diet (HFD)-fed C57BL/6J mice, we analyzed plasma biochemical parameters, insulin resistance (IR), liver histology, and the expression of inflammatory and fibrosis markers, along with hepatic lipidome. We also used a 3D hepatic spheroid model to assess their impact on profibrotic gene expression. Among the extracts, TC + PL showed a significant reduction in IR, liver weight, TNF-α, IL4, IL10 expression, and hepatic lipid levels (saturated triglycerides, ceramides, lysophosphocholines, acylcarnitines, diglycerides, and phosphatidylinositol levels). Saroglitazar reversed changes in body weight, IR, plasma triglycerides, glucose, insulin, and various hepatic lipid species (fatty acids, phospholipids, glycerophospholipids, sphingolipids, and triglycerides). With the exception of GG, Saroglitazar, and other extracts protected against palmitic acid-induced fibrosis marker gene expression in the 3D spheroids. TC + PL and Saroglitazar also effectively prevented HFD-induced insulin resistance, inflammation, and specific harmful lipid species in the liver.

Anti-obesity effects of olivetol in adult zebrafish model induced by short-term high-fat diet

Obesity is a complex disease caused by various factors, and synthetic drugs used to treat it can have side effects. Natural compounds, such as olivetol, could be a promising alternative. Olivetol is a substance found in certain lichen species and has anti-inflammatory and anti-cancer properties. In this study, researchers conducted in-silico molecular docking studies and found that olivetol had significant binding affinity with receptors involved in obesity. They also investigated the effects of olivetol on a diet-induced obese zebrafish model and found that high doses of olivetol reduced excessive fat accumulation and triglyceride and lipid accumulation. The low dose of olivetol showed a significant reduction in liver enzymes' levels. However, the high dose of olivetol resulted in a significant increase in HMG-CoA levels. These results suggest that olivetol may be a promising anti-obesity agent for the treatment of hyperlipidemia-related disorders, but further research is necessary to understand its full effects on the body.

Preventing Adipogenesis and Preserving Mitochondria and GLUT-4 Functions by Extracts and Isolated Compounds of Australian Acacia saligna

Acacia saligna's secondary metabolites show promise in treating type 2 diabetes mellitus and its related conditions. We previously discovered that methanolic extracts, isolated flavonoids, and cyclitols effectively preserve mitochondria in 3T3-L1 adipocytes. In this current work, quantification of lipid droplet levels with Oil Red O assay showed a noticeable decrease in lipogenesis in 3T3-L1 cells. Methanolic leaf and bark extracts and isolated compounds, (-)-epicatechin 6 and myricitrin 8, reduced cellular lipid levels by 21.15% to 25.28%, respectively. mRNA levels of key regulators of mitochondrial biogenesis, such as adiponectin, PGC-1α, and mtTFA, were increased. Methanolic flower extract (FL-MeOH) and its chemical components, naringenin 1 and D-(+)-pinitol 5a, increased these gene levels from 10% to 29% at the higher dose. Our study found that FL-MeOH slightly reduced pro-inflammatory cytokines TNF-α and IL-6, attributed to two phytochemicals, naringenin-7-O-α-L-arabinofuranoside 2 and D-(+)-pinitol 5a. Western blot analysis also showed that adipocytes treated with MeOH extracts had higher GLUT-4 expression levels than untreated adipocytes. Overall, A. saligna extracts and their isolated compounds demonstrated anti-lipogenesis activity during 3T3-L1 cell differentiation, modulation of transcriptional levels of adiponectin, PGC-1α, and mtTFA, reducing TNF-α and IL-6 mRNA levels, promoting mitochondrial biogenesis, and enhancing GLUT-4 expression.

Coenzyme Q10 Supplementation in Athletes: A Systematic Review

BACKGROUND

To summarize available evidence in the literature on the impacts of CoQ10 supplementation on metabolic, biochemical, and performance outcomes in athletes.

METHODS

Six databases, Cochrane Library (33 articles), PubMed (90 articles), Scopus (55 articles), Embase (60 articles), SPORTDiscus (1056 articles), and Science Direct (165 articles), were researched. After applying the eligibility criteria, articles were selected for peer review independently as they were identified by June 2022. The protocol for this systematic review was registered on PROSPERO (CRD42022357750).

RESULTS

Of the 1409 articles found, 16 were selected for this systematic review. After CoQ10 supplementation, a decrease in oxidative stress markers was observed, followed by higher antioxidant activity. On the other hand, lower levels of liver damage markers (ALT); Aspartate aminotransferase (AST); and Gamma-glutamyl transpeptidase (γGT) were identified. Finally, we found a reduction in fatigue indicators such as Creatine Kinase (CK) and an increase in anaerobic performance.

CONCLUSIONS

This systematic review concludes that supplementation with orally administered CoQ10 (30-300 mg) was able to potentiate plasma antioxidant activity and anaerobic performance, reducing markers linked to oxidative stress and liver damage in athletes from different modalities aged 17 years old and older.

Intracellular spatiotemporal metabolism in connection to target engagement

The metabolism in eukaryotic cells is a highly ordered system involving various cellular compartments, which fluctuates based on physiological rhythms. Organelles, as the smallest independent sub-cell unit, are important contributors to cell metabolism and drug metabolism, collectively designated intracellular metabolism. However, disruption of intracellular spatiotemporal metabolism can lead to disease development and progression, as well as drug treatment interference. In this review, we systematically discuss spatiotemporal metabolism in cells and cell subpopulations. In particular, we focused on metabolism compartmentalization and physiological rhythms, including the variation and regulation of metabolic enzymes, metabolic pathways, and metabolites. Additionally, the intricate relationship among intracellular spatiotemporal metabolism, metabolism-related diseases, and drug therapy/toxicity has been discussed. Finally, approaches and strategies for intracellular spatiotemporal metabolism analysis and potential target identification are introduced, along with examples of potential new drug design based on this.

Serine Threonine-Protein Kinase-Derived IW13 Improves Lipid Metabolism via C/EBP-α/SREBP1/FAS Signaling Pathways in HFD-Induced Zebrafish In Vivo Larval Model

Obesity is linked to the development of major metabolic disorders such as type 2 diabetes, cardiovascular disease, and cancer. Recent research has focused on the molecular link between obesity and oxidative stress. Obesity impairs antioxidant function, resulting in dramatically increased reactive oxygen levels and apoptosis. In this study, we investigated the effect of IW13 peptide on inhibiting lipid accumulation and regulating the antioxidant mechanism to normalize the lipid metabolism in HFD induced zebrafish larvae. Our results showed that co-treatment with IW13 peptide showed a protective effect in HFD zebra fish larvae by increasing the survival and heart rate. However, IW13 peptide co-treatment reduced triglycerides and cholesterol levels while also restoring the SOD and CAT antioxidant enzymes. In addition, IW13 co-treatment inhibited the formation of lipid peroxidation and superoxide anion by regulating the glutathione level. Also, the results showed that IW13 specifically downregulated the expression of the lipogenic-specific genes (C/EBP-α, SREBP1, and FAS). The findings exhibited that the IW13 peptide with effective antioxidant and anti-obesity activity could act as a futuristic drug to treat obesity and oxidative stress-related diseases.

Role of Oxidative Stress on Insulin Resistance in Diet-Induced Obesity Mice

Insulin resistance is the link between obesity and type 2 diabetes mellitus. The molecular mechanism by which obese individuals develop insulin resistance has not yet been fully elucidated; however, inconclusive and contradictory studies have shown that oxidative stress may be involved in the process. Thus, this study aimed to evaluate the effect of reactive species on the mechanism of insulin resistance in diet-induced obese mice. Obese insulin-resistant mice were treated with N-acetylcysteine (NAC; 50 mg/kg per day, for 15 days) by means of oral gavage. Twenty-four hours after the last NAC administration, the animals were euthanized and their tissues were extracted for biochemical and molecular analyses. NAC supplementation induced improved insulin resistance and fasting glycemia, without modifications in food intake, body weight, and adiposity. Obese mice showed increased dichlorofluorescein (DCF) oxidation, reduced catalase (CAT) activity, and reduced glutathione levels (GSH). However, treatment with NAC increased GSH and CAT activity and reduced DCF oxidation. The gastrocnemius muscle of obese mice showed an increase in nuclear factor kappa B (NFκB) and protein tyrosine phosphatase (PTP1B) levels, as well as c-Jun N-terminal kinase (JNK) phosphorylation compared to the control group; however, NAC treatment reversed these changes. Considering the molecules involved in insulin signaling, there was a reduction in insulin receptor substrate (IRS) and protein kinase B (Akt) phosphorylation. However, NAC administration increased IRS and Akt phosphorylation and IRS/PI3k (phosphoinositide 3-kinase) association. The results demonstrated that oxidative stress-associated obesity could be a mechanism involved in insulin resistance, at least in this animal model.

Fatty acid oxidation facilitates DNA double-strand break repair by promoting PARP1 acetylation

DNA repair is a tightly coordinated stress response to DNA damage, which is critical for preserving genome integrity. Accruing evidence suggests that metabolic pathways have been correlated with cellular response to DNA damage. Here, we show that fatty acid oxidation (FAO) is a crucial regulator of DNA double-strand break repair, particularly homologous recombination repair. Mechanistically, FAO contributes to DNA repair by activating poly(ADP-ribose) polymerase 1 (PARP1), an enzyme that detects DNA breaks and promotes DNA repair pathway. Upon DNA damage, FAO facilitates PARP1 acetylation by providing acetyl-CoA, which is required for proper PARP1 activity. Indeed, cells reconstituted with PARP1 acetylation mutants display impaired DNA repair and enhanced sensitivity to DNA damage. Consequently, FAO inhibition reduces PARP1 activity, leading to increased genomic instability and decreased cell viability upon DNA damage. Finally, our data indicate that FAO serves as an important participant of cellular response to DNA damage, supporting DNA repair and genome stability.

Hepatocyte-specific O-GlcNAc transferase downregulation ameliorates nonalcoholic steatohepatitis by improving mitochondrial function

O-GlcNAcylation is a post-translational modification that directly couples the processes of nutrient sensing, metabolism, and signal transduction, affecting protein function and localization, since the O-linked N-acetylglucosamine moiety comes directly from the metabolism of glucose, lipids, and amino acids. De addition and removal of O-GlcNAc of target proteins is mediated by two highly conserved enzymes: O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) and O-GlcNAcase (OGA), respectively. Deregulation of O-GlcNAcylation has been reported to be associated with various human diseases such as cancer, diabetes, and cardiovascular diseases. The contribution of deregulated O-GlcNAcylation to the progression and pathogenesis of NAFLD remains intriguing, and a better understanding of its roles in this pathophysiological context is required to uncover novel avenues for therapeutic intervention. By using a translational approach, our aim is to describe the role of OGT and O-GlcNAcylation in the pathogenesis of NAFLD. We used primary mouse hepatocytes, human hepatic cell lines and in vivo mouse models of steatohepatitis to manipulate O-GlcNAc transferase (OGT). We also studied OGT and O-GlcNAcylation in liver samples from different cohorts of people with NAFLD. O-GlcNAcylation was upregulated in the liver of people and animal models with steatohepatitis. Downregulation of OGT in NAFLD-hepatocytes improved diet-induced liver injury in both in vivo and in vitro models. Proteomics studies revealed that mitochondrial proteins were hyper-O-GlcNAcylated in the liver of mice with steatohepatitis. Inhibition of OGT is able to restore mitochondrial oxidation and decrease hepatic lipid content in in vitro and in vivo models of NAFLD. These results demonstrate that deregulated hyper-O-GlcNAcylation favors NAFLD progression by reducing mitochondrial oxidation and promoting hepatic lipid accumulation.

Loss of SFXN1 mitigates lipotoxicity and predicts poor outcome in non-viral hepatocellular carcinoma

Hepatocellular carcinoma (HCC) imposes a huge global burden, arising from various etiological factors such as hepatitis virus infection and metabolic syndrome. While prophylactic vaccination and antiviral treatment have decreased the incidence of viral HCC, the growing prevalence of metabolic syndrome has led to an increase in non-viral HCC. To identify genes downregulated and specifically associated with unfavorable outcome in non-viral HCC cases, screening analysis was conducted using publically available transcriptome data. Among top 500 genes meeting the criteria, which were involved in lipid metabolism and mitochondrial function, a serine transporter located on inner mitochondrial membrane SFXN1 was highlighted. SFXN1 protein expression was significantly reduced in 33 of 105 HCC tissue samples, and correlated to recurrence-free and overall survival only in non-viral HCC. Human HCC cells with SFXN1 knockout (KO) displayed higher cell viability, lower fat intake and diminished reactive oxygen species (ROS) production in response to palmitate administration. In a subcutaneous transplantation mouse model, high-fat diet feeding attenuated tumorigenic potential in the control cells, but not in the SFXN1-KO cells. In summary, loss of SFXN1 expression suppresses lipid accumulation and ROS generation, preventing toxic effects from fat overload in non-viral HCC, and predicts clinical outcome of non-viral HCC patients.

Aged black garlic (Allium sativum L.) and aged black elephant garlic (Allium ampeloprasum L.) alleviate obesity and attenuate obesity-induced muscle atrophy in diet-induced obese C57BL/6 mice

Garlic (Allium sativum L.) is a primary dietary component worldwide because of its health benefits and use as a traditional medicine. Elephant garlic (Allium ampeloprasum L.), a related species in the same genus, is less intense and sweeter than A. sativum. The object of this study was to investigate the alleviative effects of aged black garlic (ABG) and aged black elephant garlic (ABEG) on obesity and muscle atrophy induced by obesity in high fat diet-induced obese mice. We demonstrated that ABG and ABEG alleviated obesity and muscle atrophy and enhanced myogenic differentiation and myotube hypertrophy, and this effect was mediated by the upregulation of Akt/mTOR/p70^S6K signaling. Furthermore, a candidate bioactive compound of ABG and ABEG was suggested in this study through analysis using gas chromatography-mass spectroscopy and ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectroscopy. In conclusion, ABG and ABEG may alleviate obesity and treat obesity-induced muscle atrophy.

Green Tea and Java Pepper Mixture Prevents Obesity by Increasing Energy Expenditure and Modulating Hepatic AMPK/MicroRNA-34a/370 Pathway in High-Fat Diet-Fed Rats

This study was performed to evaluate the anti-obesity effects of green tea and java pepper mixture (GJ) on energy expenditure and understand the regulatory mechanisms of AMP-activated protein kinase (AMPK), microRNA (miR)-34a, and miR-370 pathways in the liver. Sprague-Dawley rats were divided into four groups depending on the following diets given for 14 weeks: normal chow diet (NR), 45% high-fat diet (HF), HF + 0.1% GJ (GJL), and HF + 0.2% GJ (GJH). The results revealed that GJ supplementation reduced body weight and hepatic fat accumulation, improved serum lipids, and increased energy expenditure. In the GJ-supplemented groups, the mRNA levels of genes related to fatty acid syntheses, such as a cluster of differentiation 36 (CD36), sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and stearoyl-CoA desaturase 1 (SCD1) were downregulated, and mRNA levels of peroxisome proliferator-activated receptor alpha (PPARα), carnitine/palmitoyl-transferase 1 (CPT1), and uncoupling protein 2 (UCP2), which participate in fatty acid oxidation, were upregulated in the liver. GJ increased the AMPK activity and decreased the miR-34a and miR-370 expression. Therefore, GJ prevented obesity by increasing energy expenditure and regulating hepatic fatty acid synthesis and oxidation, suggesting that GJ is partially regulated through AMPK, miR-34a, and miR-370 pathways in the liver.

The Complex Interplay between Imbalanced Mitochondrial Dynamics and Metabolic Disorders in Type 2 Diabetes

Type 2 diabetes mellitus (T2DM) is a global burden, with an increasing number of people affected and increasing treatment costs. The advances in research and guidelines improve the management of blood glucose and related diseases, but T2DM and its complications are still a big challenge in clinical practice. T2DM is a metabolic disorder in which insulin signaling is impaired from reaching its effectors. Mitochondria are the "powerhouses" that not only generate the energy as adenosine triphosphate (ATP) using pyruvate supplied from glucose, free fatty acid (FFA), and amino acids (AA) but also regulate multiple cellular processes such as calcium homeostasis, redox balance, and apoptosis. Mitochondrial dysfunction leads to various diseases, including cardiovascular diseases, metabolic disorders, and cancer. The mitochondria are highly dynamic in adjusting their functions according to cellular conditions. The shape, morphology, distribution, and number of mitochondria reflect their function through various processes, collectively known as mitochondrial dynamics, including mitochondrial fusion, fission, biogenesis, transport, and mitophagy. These processes determine the overall mitochondrial health and vitality. More evidence supports the idea that dysregulated mitochondrial dynamics play essential roles in the pathophysiology of insulin resistance, obesity, and T2DM, as well as imbalanced mitochondrial dynamics found in T2DM. This review updates and discusses mitochondrial dynamics and the complex interactions between it and metabolic disorders.

Implantation of CPT1AM-expressing adipocytes reduces obesity and glucose intolerance in mice

Obesity and its associated metabolic comorbidities are a rising global health and social issue, with novel therapeutic approaches urgently needed. Adipose tissue plays a key role in the regulation of energy balance and adipose tissue-derived mesenchymal stem cells (AT-MSCs) have gained great interest in cell therapy. Carnitine palmitoyltransferase 1A (CPT1A) is the gatekeeper enzyme for mitochondrial fatty acid oxidation. Here, we aimed to generate adipocytes expressing a constitutively active CPT1A form (CPT1AM) that can improve the obese phenotype in mice after their implantation. AT-MSCs were differentiated into mature adipocytes, subjected to lentivirus-mediated expression of CPT1AM or the GFP control, and subcutaneously implanted into mice fed a high-fat diet (HFD). CPT1AM-implanted mice showed lower body weight, hepatic steatosis and serum insulin and cholesterol levels alongside improved glucose tolerance. HFD-induced increases in adipose tissue hypertrophy, fibrosis, inflammation, endoplasmic reticulum stress and apoptosis were reduced in CPT1AM-implanted mice. In addition, the expression of mitochondrial respiratory chain complexes was enhanced in the adipose tissue of CPT1AM-implanted mice. Our results demonstrate that implantation of CPT1AM-expressing AT-MSC-derived adipocytes into HFD-fed mice improves the obese metabolic phenotype, supporting the future clinical use of this ex vivo gene therapy approach.

High-fat, high-sucrose, and combined high-fat/high-sucrose diets effects in oxidative stress and inflammation in male rats under presence or absence of obesity

The study examines the influence of three types of hypercaloric diets on metabolic parameters, inflammatory markers, and oxidative stress in experimental model. Male Wistar rats (n = 40) were randomized in control (C), high-sucrose (HS), high-fat (HF), and high-fat with sucrose (HFHS) for 20 weeks. Nutritional, metabolic, hormonal, and biochemical profiles, as well as histological analysis of adipose and hepatic tissues were performed. Inflammation and oxidative stress were determined. HF model caused obesity and comorbidities as glucose intolerance and arterial hypertension. In relation to hormonal and biochemical parameters, there was no significant difference between the groups. All groups showed increased deposition of fat droplets in the hepatic tissue, even though adipocyte areas were similar. Biomarkers of oxidative stress in serum and adipose tissues were similar among the groups. HF model was effective in triggering associated obesity and comorbidities in male rats, but all hypercaloric diets were unable to promote oxidative stress and inflammation.

Mitochondrial carnitine palmitoyltransferase-II dysfunction: A possible novel mechanism for nonalcoholic fatty liver disease in hepatocarcinogenesis

Nonalcoholic fatty liver disease (NAFLD) or metabolic-associated fatty liver disease has been characterized by the lipid accumulation with injury of hepatocytes and has become one of the most common chronic liver diseases in the world. The complex mechanisms of NAFLD formation are still under identification. Carnitine palmitoyltransferase-II (CPT-II) on inner mitochondrial membrane (IMM) regulates long chain fatty acid β-oxidation, and its abnormality has had more and more attention paid to it by basic and clinical research in NAFLD. The sequences of its peptide chain and DNA nucleotides have been identified, and the catalytic activity of CPT-II is affected on its gene mutations, deficiency, enzymatic thermal instability, circulating carnitine level and so on. Recently, the CPT-II dysfunction has been discovered in models of liver lipid accumulation. Meanwhile, the malignant transformation of hepatocyte-related CD44+ stem T cell activation, high levels of tumor-related biomarkers (AFP, GPC3) and abnormal activation of Wnt3a expression as a key signal molecule of the Wnt/β-catenin pathway run parallel to the alterations of hepatocyte pathology. This review focuses on some of the progress of CPT-II inactivity on IMM with liver fatty accumulation as a possible novel pathogenesis for NAFLD in hepatocarcinogenesis.

Essential role for albumin in preserving liver cells from TNFα-induced mitochondrial injury

Cytokine-induced inflammation and mitochondrial oxidative stress are key drivers of liver tissue injury. Here, we describe experiments modeling hepatic inflammatory conditions in which plasma leakage leads to large amounts of albumin to reach the interstitium and parenchymal surfaces to explore whether this protein plays a role in preserving hepatocyte mitochondria against the damaging actions of the cytotoxic cytokine tumor necrosis factor alpha (TNFα). Hepatocytes and precision-cut liver slices were cultured in the absence or presence of albumin in the cell media and then exposed to mitochondrial injury with the cytokine TNFα. The homeostatic role of albumin was also investigated in a mouse model of TNFα-mediated liver injury induced by lipopolysaccharide and D-galactosamine (LPS/D-gal). Mitochondrial ultrastructure, oxygen consumption, ATP and reactive oxygen species (ROS) generation, fatty acid β-oxidation (FAO), and metabolic fluxes were assessed by transmission electron microscopy (TEM), high-resolution respirometry, luminescence-fluorimetric-colorimetric assays and NADH/FADH₂ production from various substrates, respectively. TEM analysis revealed that in the absence of albumin, hepatocytes were more susceptible to the damaging actions of TNFα and showed more round-shaped mitochondria with less intact cristae than hepatocytes cultured with albumin. In the presence of albumin in the cell media, hepatocytes also showed reduced mitochondrial ROS generation and FAO. The mitochondria protective actions of albumin against TNFα damage were associated with the restoration of a breakpoint between isocitrate and α-ketoglutarate in the tricarboxylic acid cycle and the upregulation of the antioxidant activating transcription factor 3 (ATF3). The involvement of ATF3 and its downstream targets was confirmed in vivo in mice with LPS/D-gal-induced liver injury, which showed increased hepatic glutathione levels, indicating a reduction in oxidative stress after albumin administration. These findings reveal that the albumin molecule is required for the effective protection of liver cells from mitochondrial oxidative stress induced by TNFα. These findings emphasize the importance of maintaining the albumin levels in the interstitial fluid within the normal range to protect the tissues against inflammatory injury in patients with recurrent hypoalbuminemia.

Butyrate and obesity: Current research status and future prospect

Over the past few decades, increasing prevalence of obesity caused an enormous medical, social, and economic burden. As the sixth most important risk factor contributing to the overall burden of disease worldwide, obesity not only directly harms the human body, but also leads to many chronic diseases such as diabetes, cardiovascular diseases (CVD), nonalcoholic fatty liver disease (NAFLD), and mental illness. Weight loss is still one of the most effective strategies against obesity and related disorders. Recently, the link between intestinal microflora and metabolic health has been constantly established. Butyrate, a four-carbon short-chain fatty acid, is a major metabolite of the gut microbiota that has many beneficial effects on metabolic health. The anti-obesity activity of butyrate has been demonstrated, but its mechanisms of action have not been fully described. This review summarizes current knowledge of butyrate, including its production, absorption, distribution, metabolism, and the effect and mechanisms involved in weight loss and obesity-related diseases. The aim was to contribute to and advance our understanding of butyrate and its role in obesity. Further exploration of butyrate and its pathway may help to identify new anti-obesity.

Cyclopia intermedia (Honeybush) Induces Uncoupling Protein 1 and Peroxisome Proliferator-Activated Receptor Alpha Expression in Obese Diabetic Female db/db Mice

Previously, we reported that a crude polyphenol-enriched fraction of Cyclopia intermedia (CPEF), a plant consumed as the herbal tea, commonly known as honeybush, reduced lipid content in 3T3-L1 adipocytes and inhibited body weight gain in obese, diabetic female leptin receptor-deficient (db/db) mice. In the current study, the mechanisms underlying decreased body weight gain in db/db mice were further elucidated using western blot analysis and in silico approaches. CPEF induced uncoupling protein 1 (UCP1, 3.4-fold, p < 0.05) and peroxisome proliferator-activated receptor alpha (PPARα, 2.6-fold, p < 0.05) expression in brown adipose tissue. In the liver, CPEF induced PPARα expression (2.2-fold, p < 0.05), which was accompanied by a 31.9% decrease in fat droplets in Hematoxylin and Eosin (H&E)-stained liver sections (p < 0.001). Molecular docking analysis revealed that the CPEF compounds, hesperidin and neoponcirin, had the highest binding affinities for UCP1 and PPARα, respectively. This was validated with stabilising intermolecular interactions within the active sites of UCP1 and PPARα when complexed with these compounds. This study suggests that CPEF may exert its anti-obesity effects by promoting thermogenesis and fatty acid oxidation via inducing UCP1 and PPARα expression, and that hesperidin and neoponcirin may be responsible for these effects. Findings from this study could pave the way for designing target-specific anti-obesity therapeutics from C. intermedia.

Associations of breast cancer related exposures and gene expression profiles in normal breast tissue-The Norwegian Women and Cancer normal breast tissue study

BACKGROUND

Normal breast tissue is utilized in tissue-based studies of breast carcinogenesis. While gene expression in breast tumor tissue is well explored, our knowledge of transcriptomic signatures in normal breast tissue is still incomplete. The aim of this study was to investigate variability of gene expression in a large sample of normal breast tissue biopsies, according to breast cancer related exposures (obesity, smoking, alcohol, hormone therapy, and parity).

METHODS

We analyzed gene expression profiles from 311 normal breast tissue biopsies from cancer-free, post-menopausal women, using Illumina bead chip arrays. Principal component analysis and K-means clustering was used for initial analysis of the dataset. The association of exposures and covariates with gene expression was determined using linear models for microarrays.

RESULTS

Heterogeneity of the breast tissue and cell composition had the strongest influence on gene expression profiles. After adjusting for cell composition, obesity, smoking, and alcohol showed the highest numbers of associated genes and pathways, whereas hormone therapy and parity were associated with negligible gene expression differences.

CONCLUSION

Our results provide insight into associations between major exposures and gene expression profiles and provide an informative baseline for improved understanding of exposure-related molecular events in normal breast tissue of cancer-free, post-menopausal women.