Molecular Mechanisms of Adipogenesis: The Anti-adipogenic Role of AMP-Activated Protein Kinase

Integration of Conjugated Linoleic Acid-Producing Probiotic Strains Having Anti-adipogenic Properties with Honey and Oyster Mushrooms for the Formulation of Non-dairy Probiotic Beverage

Conjugated linoleic acid (CLA) has been linked to various health benefits, including anti-cancer, anti-diabetic, and anti-obesity effects. Obesity, marked by abnormal fat deposition, increases the risk of metabolic disorders such as cardiovascular diseases and type-2 diabetes. Natural anti-adipogenic modulators with insulin sensitivity are one of the approaches to address the issue. In the present study, four distinct CLA-producing probiotic strains (Lacticaseibacillus paracasei LUL:01, Latilactobacillus curvatus LGM:16, Lactiplantibacillus paraplantarum LRJ1:09, and Enterococcus faecalis LJM:05) were assessed in vitro for their potential anti-adipogenic properties using 3T3-L1 preadipocytes. Out of four strains, LGM:16 inhibited lipid accumulation (100.27%), reduced intracellular triglyceride content (168.42, 168.16, and 153.66 mg/dL in a dose-dependent manner), and enhanced insulin sensitivity (32.23%) by increasing glucose uptake. Quantitative reverse-transcription polymerase chain reaction revealed the expression genes (PPARγ, C/EBPα, and GLUT-4) in LGM:16 strain. Consequently, LGM: 16 was used to develop a non-dairy probiotic formulation incorporating honey and Pleurotus ostreatus mushroom, ensuring a probiotic count above the minimum recommended level of 6 Log10 CFU/mL. Further, response surface methodology optimized probiotic beverage formulation to achieve favorable nutritional, good sensory profile, antioxidant, and anti-obesity activity, making it a promising candidate for health benefits.

Implications of obesity-mediated cellular dysfunction and adipocytokine signaling pathways in the pathogenesis of osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease characterized by cartilage degradation, bone sclerosis, and chronic low-grade inflammation. Aging and injury play key roles in OA pathogenesis by triggering the release of proinflammatory factors from adipose tissue and other sources. Obesity and aging impair the function of endoplasmic reticulum (ER) chaperones, leading to ER stress, protein misfolding, and cellular apoptosis. Obesity also induces mitochondrial dysfunction in OA through oxidative stress and disrupts mitochondrial dynamics, exacerbating chondrocyte damage. These factors contribute to inflammation, matrix imbalance, and chondrocyte apoptosis. Adipocytes, the primary source of adipokines, release inflammatory mediators that affect joint cells. Several adipocytokines have a central role in the regulation of many aspects of inflammation. Adiponectin and leptin are the two most abundant adipocytokines that are strongly associated with OA progression. This literature review suggests that adipokines activate many signaling pathways to exert downstream effects and play significant roles in obesity-induced OA. Understanding this rapidly growing family of mainly adipocyte-derived mediators and obesity-mediated cellular dysfunction may be important in the development of new therapies for obesity-associated OA management.

Harnessing the Power of Donkey's Milk and Homemade Pickles: Unveiling Oxalate-Degrading Probiotics and Their Heat-Killed Cells as Antiadipogenic Agents in 3T3-L1 Adipocytes

Gut microbial dysbiosis is associated with the development of critical clinical conditions of metabolic syndrome (obesity, type II diabetes), and calcium oxalate kidney stones. The human gut microbial eubiosis with functional probiotics and their heat-killed cells of lactic acid bacteria (LAB) is considered the current therapy for metabolic syndrome (MS). In accordance with this, our study aimed to isolate oxalate-degrading, cholesterol-lowering, and anti-adipogenic bacterial strains from raw donkey's milk and homemade fermented pickles. Nine LAB strains with potential in vitro oxalate degrading, α-glucosidase inhibiting, and cholesterol-lowering activities were pre-screened from fourteen isolates. Further, the heat-killed cells of selected strains were evaluated for anti-adipogenic activity in murine 3T3-L1 adipocytes. This activity was examined by studying the lipid storage, gene, and protein expression of adipogenic and lipogenic transcription factors. Subsequently, four potential isolates demonstrated a significant reduction in lipid storage by limiting adipogenesis (reducing C/EBPα, PPARγ expression), lipid transportation (downregulating aP2 expression), and lipogenesis (reducing PLIN-1 expression). These effective isolates were characterized using 16S rRNA molecular sequencing, and were identified as closest relatives to the Enterococcus (RRLA5, RRLA1, and RRLD6) and Lactobacillus (RRLM2) genera. Further, they displayed good survivability under in vitro gastric conditions and non-haemolytic activity. Taken together, the live cells of effective isolates depicted significant in vitro oxalate degradation, and their heat-killed cells demonstrated anti-adipogenic activity through downregulating the adipogenesis and lipogenesis. Moreover, future preclinical animal model studies on the synergistic role of probiotics and their heat-killed cells in disease prevention through gut microbial modulation could provide evidence as a biotherapeutic agent.

Rubia akane Nakai Fruit Extract Improves Obesity and Insulin Sensitivity in 3T3-L1 Adipocytes and High-Fat Diet-Induced Obese Mice

A rise in obesity during the COVID-19 pandemic has spurred the development of safe and effective natural anti-obesity agents. In this study, we propose Rubia akane Nakai fruit extract (RFE) as a potential natural product-based anti-obesity agent. R. akane Nakai is a plant of the Rubiaceae family that grows throughout Republic of Korea. Its roots have long been used medicinally and are known for various bioactivities, but the fruit's bioactivities are unexplored. We investigated the anti-obesity effects of RFE using 3T3-L1 adipocytes and high-fat diet-induced obese mice. In 3T3-L1 adipocytes, RFE inhibited adipogenic differentiation and lipogenesis by downregulating PPARγ (peroxisome proliferator-activated receptor γ), C/EBPα (CCAAT enhancer-binding protein α), and SREBP-1 (sterol regulatory element-binding protein 1) through AMPK (AMP-activated protein kinase) activation and by delaying the initiation of MCE (mitotic clonal expansion), which is essential for early adipogenesis. At the in vivo level, RFE improved the phenotypes of obesity and insulin resistance. In white adipose tissue, RFE not only suppressed adipogenic differentiation and lipogenesis through AMPK activation but also improved insulin sensitivity by upregulating basal GLUT4 (glucose transporter type 4) expression. Therefore, this study advances RFE as a potential natural treatment for obesity and insulin resistance.

Unsaturated fatty acids enhance mitochondrial function and PGC1-α expression in brown adipose tissue of obese mice on a low-carbohydrate diet

Brown adipose tissue (BAT) exhibits greater resilience against inflammation compared to white adipose tissue. However, chronic consumption of a high-fat diet can render brown adipocytes vulnerable to proinflammatory conditions, leading to a decline in their thermogenic capacity and subsequent dysfunction. The analysis of the effects of type fatty acids intake must be important in the context of the dietary pattern and obesity. This study aims to investigate the impact of a low-carbohydrate/high-fat diet, enriched with different types of fatty acids, on mitochondrial activity on brown adipose tissue in obese mice. Male mice were allocated into different dietary groups: a control diet (CTL), and a high-fat diet (HFD) for a duration of 10 weeks to induce obesity. Subsequently, the HFD group was subdivided into the following categories for an additional 6 weeks: HFD with a low carbohydrate content enriched with saturated fatty acids; HFD with a low carbohydrate content enriched with fish oil; HFD with a low carbohydrate content enriched with soybean oil; and HFD with a low carbohydrate content enriched with olive oil. The findings indicated that in comparison to a low-carbohydrate diet rich in saturated fats, diets rich in unsaturated fatty acids-particularly omega-6 (n-6) and omega-9 (n-9)-resulted in elevated expression of UCP1, a marker of BAT activity. Moreover, there was an increase in the expression of PGC1-α, a protein involved in mitochondrial biogenesis, and enhanced functionality of the oxidative phosphorylation system within BAT mitochondria. These results suggest that n-6 and n-9 fatty acids may confer greater benefits to BAT functionality than saturated fats within the context of a low-carbohydrate diet. Therefore, this study revealed some molecular components that mediate BAT mitochondria function influenced by different fatty acids in a low carbohydrate diet, making it an important therapeutic target in obesity.

Crosstalk Between Antioxidants and Adipogenesis: Mechanistic Pathways and Their Roles in Metabolic Health

The interplay between oxidative stress and adipogenesis is a critical factor in the development of obesity and its associated metabolic disorders. Excessive reactive oxygen species (ROS) disrupt key transcription factors such as peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα), impairing lipid metabolism, promoting adipocyte dysfunction, and exacerbating inflammation and insulin resistance. Antioxidants, classified as endogenous (e.g., glutathione, superoxide dismutase, and catalase) and exogenous (e.g., polyphenols, flavonoids, and vitamins C and E), are pivotal in mitigating these effects by restoring redox balance and preserving adipocyte functionality. Endogenous antioxidants neutralize ROS and safeguard cellular structures; however, under heightened oxidative stress, these defenses are often insufficient, necessitating dietary supplementation. Exogenous antioxidants derived from plant-based sources, such as polyphenols and vitamins, act through direct ROS scavenging, upregulation of endogenous antioxidant enzymes, and modulation of key signaling pathways like nuclear factor kappa B (NF-κB) and PPARγ, reducing lipid peroxidation, inflammation, and adipocyte dysfunction. Furthermore, they influence epigenetic regulation and transcriptional networks to restore adipocyte differentiation and limit lipid accumulation. Antioxidant-rich diets, including the Mediterranean diet, are strongly associated with improved metabolic health, reduced obesity rates, and enhanced insulin sensitivity. Advances in personalized antioxidant therapies, guided by biomarkers of oxidative stress and supported by novel delivery systems, present promising avenues for optimizing therapeutic interventions. This review, "Crosstalk Between Antioxidants and Adipogenesis: Mechanistic Pathways and Their Role in Metabolic Health", highlights the mechanistic pathways by which antioxidants regulate oxidative stress and adipogenesis to enhance metabolic health.

Sleep deprivation stimulates adaptive thermogenesis by activating AMPK pathway in mice

Sleep deprivation (SD) can affect the adaptive thermogenesis in laboratory rodents, but the molecular mechanism and the crosstalk with other organs remain largely unknown. In order to investigate the effects and mechanisms of SD on thermoregulation and energy metabolism, here we measured the changes of body weight, body fat mass, body temperature, resting metabolic rate (RMR), and thermogenic gene expression in brown adipose tissue (BAT), white adipose tissue (WAT), skeleton muscle and liver in C57BL/6J mice during 7-day SD with rotating rod sleep deprivation device. Results showed that compared with the control group, the body weight and body fat mass of SD mice were decreased and RMR of SD mice increased. The gene expression of Ampk, Pgc1α and Ucp1 which related to thermogenesis in BAT and WAT were significantly increased, and the expression of Ampk, Serca1, Serca2 and Ucp3 which related to thermogenesis in skeletal muscle were significantly increased in SD mice. Taken together, these data demonstrated that 7-day SD enhanced the adaptive thermogenesis in mice by activating AMPK, including the upregulation of the AMPK - PGC1α - UCP1 pathway in BAT, and the AMPK - UCP3 and SLN - SERCA pathway in skeleton muscle. Our data provide the molecular evidence for SD-stimulated adaptive thermogenesis and energy metabolism in small mammals.

Spotlight on the Mechanism of Action of Semaglutide

Initially intended to control blood glucose levels in patients with type 2 diabetes, semaglutide, a potent glucagon-like peptide 1 analogue, has been established as an effective weight loss treatment by controlling appetite. Integrating the latest clinical trials, semaglutide in patients with or without diabetes presents significant therapeutic efficacy in ameliorating cardiometabolic risk factors and physical functioning, independent of body weight reduction. Semaglutide may modulate adipose tissue browning, which enhances human metabolism and exhibits possible benefits in skeletal muscle degeneration, accelerated by obesity and ageing. This may be attributed to anti-inflammatory, mitochondrial biogenesis, antioxidant and autophagy-regulating effects. However, most of the supporting evidence on the mechanistic actions of semaglutide is preclinical, demonstrated in rodents and not actually confirmed in humans, therefore warranting caution in the interpretation. This article aims to explore potential innovative molecular mechanisms of semaglutide action in restoring the balance of several interlinking aspects of metabolism, pointing to distinct functions in inflammation and oxidative stress in insulin-sensitive musculoskeletal and adipose tissues. Moreover, possible applications in protection from infections and anti-aging properties are discussed. Semaglutide enhancement of the core molecular mechanisms involved in the progress of obesity and diabetes, although mostly preclinical, may provide a framework for future research applications in human diseases overall.

Sucralose-Enhanced Adipogenesis on Preadipocyte Human Cell Line During Differentiation Process

Sucralose, a commonly nonnutritive sweetener used in daily products of habitual diet, is related to impairing the gut microbiome by disrupting inflammatory response, promoting weight gain by increasing adipose tissue and promoting chronic inflammatory processes. Considering the impact of sucralose in the development of metabolic diseases, in this work, we focused on the impact of sucralose on the adipocyte differentiation process to determine if sucralose can promote adipogenesis and increase adipose tissue depots in PCS 210 010 human preadipocytes cell line. Sucralose at 25 (S25) and 100 ng/µL (S100) concentrations were tested against control with no edulcorant (NS) during the adipocyte differentiation process at 48 h and 96 h. The genetic expression of adipogenesis markers such as CEBP-α, PPARγ, EBF-2, UCP-1, and lipogenesis regulator ACC was determined by qPCR. A panel of human cytokines related to inflammatory response was measured by a flow cytometer using the kit Legend Plex Human Cytokine panel of BIOLUMINEX. Our results indicate that sucralose increased the expression of white adipocyte differentiation marker CEBP-α and lipogenesis regulator ACC at 96 h before complete differentiation. Also, sucralose triggers an inflammatory response by synthesizing adiponectin, resistin, IL-6, IL-8, and Il-1B. To summarize, sucralose stimulates the expression of genes related to adipogenesis and negatively affects the secretion of inflammatory cytokines and adipokines during preadipocyte differentiation.

Cytotoxicity, Antiadipogenic, Low-Density Lipoprotein Oxidation Inhibitory Activities, and Acute Toxicity Study of Psychotria densinervia Hydroethanolic Leaf and Bark Extracts

Background: Obesity is increasingly taking an important stage as a cause of death worldwide, and interventions with a good cost-effectiveness ratio are needed. Psychotria densinervia is one of these natural products with health benefits. Objective. The present study evaluated the cytotoxicity, antiadipogenic, low-density lipoprotein (LDL), oxidation inhibitory activities, and acute toxicity of Psychotria densinervia hydroethanolic leaf and bark extracts. Methods: The cytotoxicity evaluation of the extracts (62.5, 125, 250, and 500 μg/mL) using the MTT assay and the antiadipogenic activity (25, 50, 100, and 200 μg/mL) using oleic acid were carried out in SW-872 cells. Copper sulfate (CuSO4)-induced oxidation was used in the evaluation of the effect of extracts (0.25, 0.5, and 1 mg/mL) against LDL oxidation. The oral acute toxicity evaluation of a single dose of 2000 mg/kg of the extracts was performed in Wistar albino rats weighing 127 ± 2 g. Results: The leaf and bark extracts did not show any sign of cytotoxicity at the tested concentrations. The best antiadipogenic activity was observed by the standard orlistat (38.45 ± 1.70 μg/mL), followed by the leaf extract (IC50: 41.47 ± 0.50 μg/mL) and the least the bark extract (IC50: 107.50 ± 0.90 μg/mL). At a concentration of 1 mg/mL, the leaf extract presented an oxidation lag time of 130 min, which was higher and better than that of the bark extract (120 min). Quercetin (standard) presented an oxidation lag time longer than 3 h. The oral acute toxicity evaluation did not show any signs of toxicity indicating that the LD50 was greater than 2000 mg/kg. Conclusion: Based on the results obtained, the P. densinervia hydroethanolic leaf extract possesses a better antioxidant and antiadipogenic activities than the bark extract.

Piperlongumine inhibits the early stage of adipogenesis in 3T3-L1 cells

Piperlongumine (PLM), a natural compound isolated from long peppers, has been reported to possess multiple pharmacological roles, including anti-tumor and anti-diabetic. However, the pharmacological role of PLM on adipogenesis is still unknown. In this study, we found that PLM strongly inhibited 3T3-L1 adipocyte differentiation. This inhibition was determined by the accumulation of lipid droplets and intracellular triglycerides. In addition, PLM downregulated both the mRNA and protein expression of adipogenic transcription factors, including CCAAT-enhancer binding proteins β (C/EBPβ), C/EBPα, and peroxisome proliferator-activated receptor γ (PPARγ). Based on the time-course experiment, we found that the inhibitory effect of PLM on adipogenesis was mainly involved in the early stage of adipogenesis. Studying these differential effects could uncover new mechanisms for regulating adipogenesis and new chemicals for treating obesity.

Synergistic Fat-Reducing Effect of Deoxycholic Acid and Rhein in Lipid-Based Nanoparticles with Reduced Toxicity for Obesity Treatment

Purpose

Injectable deoxycholic acid (DA) has been approved for removing excess submental fat and is off-label for local adipose tissue reduction. Conventional DA injections fail to control fat reduction and generate severe adverse effects in adjacent non-adipose tissues. We designed squarticles as lipid-based nanoparticles for DA delivery to reduce fat accumulation.

Methods

The liquid lipid phase of the squarticles was composed of squalene, which was previously reported to sequester the toxicity of overdosed drugs. Rhein, a natural anti-adipogenic compound, was incorporated into the squarticles for combined fat-lowering.

Results

The squarticles had an average diameter of 93 nm and high rhein encapsulation (96%). The nanoparticles were easily internalized into mature adipocytes and were located in the lysosomes. DA induces adipocyte death via apoptosis and necrosis; however, nanoencapsulation can decrease cell death. Compared to free DA, squarticles showed superior mitigation of cytotoxicity against non-targeted cells (skin fibroblasts). Oil Red O staining indicated that squarticles loaded with DA or rhein alone inhibited lipid droplets by 42% and 17%, respectively. DA and rhein worked together in squarticles to further suppress fat accumulation by 50%. Dual administration of DA and rhein to the nanocarriers downregulated adipokines. The intraperitoneal administration of squarticles loaded with DA and rhein significantly decreased body weight, total cholesterol, and adipokine release. Histological analysis revealed that squarticles reduced adipocyte hypertrophy in the groin and epididymis by 11% and 53%, respectively. We examined the toxicity of the combination of DA+rhein in healthy rats that received a dose three-fold higher than that used in the pharmacological assessment. The survival rate of the overdosed DA+rhein increased from 50% to 100% after nanoencapsulation. Free compounds induce ascites, liver size reduction, AST/ALT elevation (1.5-fold), and potassium imbalance in rats. Nanoencapsulation significantly reduced these adverse effects.

Conclusion

Our findings highlight the potential of squarticles for treating obesity.

Resveratrol and Its Derivatives Diminish Lipid Accumulation in Adipocytes In Vitro-Mechanism of Action and Structure-Activity Relationship

BACKGROUND AND OBJECTIVES

Expansion of white adipose tissue causes systemic inflammation and increased risk of metabolic diseases due to its endocrine function. Resveratrol was suggested to be able to prevent obesity-related disorders by mimicking caloric restriction; however, its structure-activity relationships and molecular targets are still unknown. We aimed to compare the effects of resveratrol and its analogues on adipocyte metabolism and lipid accumulation in vitro.

METHODS

Mouse embryonic fibroblasts were differentiated to adipocytes in the absence or presence of resveratrol or its derivatives (oxyresveratrol, monomethylated resveratrol, or trimethylated resveratrol). Intracellular lipid content was assessed by Oil Red O staining. Glucose uptake and its response to insulin were estimated by 2-NBDG, and mitochondrial activity was assayed via resazurin reduction. Involvement of potential molecular pathways was investigated by concurrent treatment with their inhibitors.

RESULTS

Although lipid accumulation was significantly reduced by all analogues without altering protein content, oxyresveratrol was the most potent (IC50 = 4.2 μM), while the lowest potency was observed with trimethylated resveratrol (IC50 = 27.4 μM). Increased insulin-stimulated glucose uptake was restored by each analogue with comparable efficiency. The enhanced mitochondrial activity was normalized by resveratrol and its methylated derivatives, while oxyresveratrol had a minor impact on it. Among the examined pathways, inhibition of SIRT1, PGC-1α, and JNK diminished the lipid-reducing effect of the compounds. Autophagy appeared to play a key role in the effect of all compounds but oxyresveratrol.

CONCLUSIONS

Resveratrol and its analogues can mimic caloric restriction with complex mechanisms, including activation of SIRT1, PGC-1α, and JNK, making them possible drug candidates to treat obesity-related diseases.

Crosstalk between adipogenesis and aging: role of polyphenols in combating adipogenic-associated aging

In the last forty years, the number of people over 60 years of age has increased significantly owing to better nutrition and lower rates of infectious diseases in developing countries. Aging significantly impacts adipose tissue, which plays crucial role in hormone regulation and energy storage. This can lead to imbalances in glucose, and overall energy homeostasis within the body. Aging is irreversible phenomena and potentially causing lipid infiltration in other organs, leading to systemic inflammation, metabolic disorders. This review investigates various pathways contributing to aging-related defects in adipogenesis, such as changes in adipose tissue function and distribution. Polyphenols, a diverse group of natural compounds, can mitigate aging effects via free radicals, oxidative stress, inflammation, senescence, and age-related diseases. Polyphenols like resveratrol, quercetin and EGCG exhibit distinct mechanisms and regulate crucial pathways, such as the TGF-β, AMPK, Wnt, PPAR-γ, and C/EBP transcription factors, and influence epigenetic modifications, such as DNA methylation and histone modification. This review highlights the critical importance of understanding the intricate relationship between aging and adipogenesis for optimizing well-being with increasing age. These findings highlight the therapeutic potential of polyphenols like quercetin and resveratrol in enhancing adipose tissue function and promoting healthy aging.

Resequencing of Brazilian locally adapted cattle breeds revealed variants in candidate genes and transcription factors for meat fatty acid profile

The beef cattle industry has experienced a shift driven by a market demand for healthier meat, cost efficiency and environmental sustainability in recent years. Consequently, there has been a growing focus on the fatty acids content and functions of meat in cattle breeding programmes. Besides, a deeper understanding of the biological mechanisms influencing the expression of different phenotypes related to fatty acid profiles is crucial. In this study, we aimed to identify Single-Nucleotide Variants (SNV) and Insertion/Deletion (InDels) DNA variants in candidate genes related to fatty acid profiles described in genomic, transcriptomic and proteomic studies conducted in beef cattle breeds. Utilizing whole-genome re-sequencing data from Brazilian locally adapted bovine breeds, namely Caracu and Pantaneiro, we identified SNVs and InDels associated with 23,947 genes. From these, we identified 318 candidate genes related to fatty acid profiles that contain variants. Subsequently, we select only genes with SNVs and InDels in their promoter, 5' UTR and coding region. Through the gene-biological process network, approximately 19 genes were highlighted. Furthermore, considering the studied trait and a literature review, we selected the main transcription factors (TF). Functional analysis via gene-TF network allowed us to identify the 30 most likely candidate genes for meat fatty acid profile in cattle. LIPE, MFSD2A and SREBF1 genes were highlighted in networks due to their biological importance. Further dissection of these genes revealed 15 new variants found in promoter regions of Caracu and Pantaneiro sequences. The gene networks facilitated a better functional understanding of genes and TF, enabling the identification of variants potentially related to the expression of candidate genes for meat fatty acid profiles in cattle.

Withanolides-enriched leaf extract of Withania somnifera exert anti-obesity effects by inducing brown adipocyte-like phenotype via tuning MAP-kinase signaling axis

Present study investigated anti-obesity potential of Withania somnifera (L.) Dunal leaf extract (WSLE). Phytochemical characterization of WSLE was performed by UPLC/MS-QToF and HPLC-based analysis. WSLE was assessed for its effect on lipid metabolism and mitochondrial biogenesis in vitro using differentiated 3T3-L1 adipocytes. WSLE was found to contain 59 phytometabolites with a total of 10.601 μg withanolides per mg of extract. WSLE (30 μg/ml) treatment decreased basal levels of intracellular lipids and triglycerides to 13.85 % and 41.58 %, respectively. WSLE downregulated the expression of PPARγ, C/EBPα, C/EBPβ, and their target genes responsible for lipogenesis dose-dependently. An upregulation in expression of lipolytic (ATGL and HSL), thermogenic (PGC1α, UCP1, and PRDM16), and glucose transporter (GLUT4) genes was also observed. Furthermore, WSLE treatment increased glucose uptake by 1.5-fold. These beneficial effects of WSLE were abolished in presence of AMPK, p38MAPK, and ERK inhibitors. These observations were then validated in vivo using Caenorhabditis elegans as a model organism. Intriguingly, WSLE diminished fat accumulation in wild-type N2 worms as evident from reduced Oil-red-O staining and reduction in GFP expression of fat-5, 6, and 7 in transgenic strains. Overall, these results highlight anti-obesity potential of WSLE exerting its effects via alterations in AMPK/p38MAPK/ERK axis.

Clopidogrel ameliorates high-fat diet-induced hepatic steatosis in mice through activation of the AMPK signaling pathway and beyond

Introduction

Metabolic dysfunction-associated steatotic liver disease (MASLD) frequently confers an increased risk of vascular thrombosis; however, the marketed antiplatelet drugs are investigated for the prevention and treatment of MASLD in patients with these coexisting diseases.

Methods

To determine whether clopidogrel could ameliorate high-fat diet (HFD)-induced hepatic steatosis in mice and how it works, mice were fed on normal diet or HFD alone or in combination with or without clopidogrel for 14 weeks, and primary mouse hepatocytes were treated with palmitate/oleate alone or in combination with the compounds examined for 24 h. Body weight, liver weight, insulin resistance, triglyceride and total cholesterol content in serum and liver, histological morphology, transcriptomic analysis of mouse liver, and multiple key MASLD-associated genes and proteins were measured, respectively.

Results and discussion

Clopidogrel mitigated HFD-induced hepatic steatosis (as measured with oil red O staining and triglyceride kit assay) and reduced elevations in serum aminotransferases, liver weight, and the ratio of liver to body weight. Clopidogrel downregulated the expression of multiple critical lipogenic (Acaca/Acacb, Fasn, Scd1, Elovl6, Mogat1, Pparg, Cd36, and Fabp4), profibrotic (Col1a1, Col1a2, Col3a1, Col4a1, Acta2, and Mmp2), and proinflammatory (Ccl2, Cxcl2, Cxcl10, Il1a, Tlr4, and Nlrp3) genes, and enhanced phosphorylation of AMPK and ACC. However, compound C (an AMPK inhibitor) reversed enhanced phosphorylation of AMPK and ACC in clopidogrel-treated primary mouse hepatocytes and alleviated accumulation of intracellular lipids. We concluded that clopidogrel may prevent and/or reverse HFD-induced hepatic steatosis in mice, suggesting that clopidogrel could be repurposed to fight fatty liver in patients.

Royal Jelly Exerts a Potent Anti-Obesity Effect in Rats by Activating Lipolysis and Suppressing Adipogenesis

Background/Objective: This study examined the anti-obesity effect of royal jelly (RJ) in rats fed with a high-fat diet by targeting the major pathways involved in adipogenesis and lipolysis. In addition, it examined whether this effect is AMPK-dependent. Methods: Five groups of adult male albino rats were used (n = 6 each as 1); the control rats were fed with a normal diet (2.9 kcal), and the other groups were as follows: control + RJ (300 mg/kg), HFD (4.75 kcal), HFD + RJ (300 mg/kg), and HFD + RJ (300 mg/kg) + dorsomorphin (an AMPK inhibitor) (0.2 mg/kg). Results: RJ was administered orally to all rats. With no changes in food and energy intake, RJ significantly reduced gains in body weight, fat weight, body mass index (BMI), the Lee index, abdominal circumference (AC), and the adiposity index (AI). It also reduced fasting glucose and insulin levels, HOMA-IR, and the circulatory levels of free fatty acids (FFAs), triglycerides, cholesterol, and LDL-c in the HFD-fed rats. RJ also increased serum glycerol levels and adiponectin levels, but reduced the serum levels of leptin, IL-6, and TNF-α. Moreover, RJ reduced the secretion of IL-6 and TNF-α from isolated WAT. At the tissue level, the HFD + RJ rats exhibited a smaller adipocyte size compared to the HFD rats. At the molecular level, RJ increased the phosphorylation of AMPK, SREBP1, and ACC-1 and increased the mRNA and protein levels of HSL and ATG in the WAT of the HFD rats. In concomitance, RJ increased the mRNA levels of PGC-α1, reduced the protein levels of PPARγ, and repressed the transcriptional activities of PPARγ, SREBP1, and C/EBPαβ in the WAT of these rats. All the aforementioned effects of RJ were prevented by co-treatment with dorsomorphin. Conclusions: RJ exerts a potent anti-obesity effect in rats that is mediated by the AMPk-dependent suppression of WAT adipogenesis and the stimulation of lipolysis.

Identification of novel anti-obesity saponins from the ovary of sea cucumber (Stichopus japonicus)

The potential anti-obesity effects of sea cucumber extract have been reported. However, the individual saponins responsible for these effects are yet to be isolated and characterized. This study aimed to identify the most effective sea cucumber body part for inhibiting lipid accumulation in adipocytes and to elucidate the compounds responsible for this effect using nuclear magnetic resonance (NMR) techniques. Sea cucumber ovary 80 % ethanol extract (SCOE) demonstrated remarkable efficacy in inhibiting adipocyte differentiation compared to other sea cucumber body parts with 50 % or 80 % ethanol extracts. SCOE anti-obesity effect was evaluated in C57BL/6 mice fed a high-fat diet, which revealed significant reductions in body weight, serum lipids, adipose tissue, and liver weight. Using column chromatography, eight saponins were isolated from the SCOE, four of which exhibited potent inhibitory effects on adipocyte differentiation. Of these, three active saponins, holotoxins A, B, and D1, were newly identified. These findings highlight the potential of SCOE and its saponins as effective anti-obesity agents.

L-Fucose-Rich Sulfated Glycans from Edible Brown Seaweed: A Promising Functional Food for Obesity and Energy Expenditure Improvement

The global obesity epidemic, exacerbated by the sedentary lifestyle fostered by the COVID-19 pandemic, presents a growing socioeconomic burden due to decreased physical activity and increased morbidity. Current obesity treatments show promise, but they often come with expensive medications, frequent injections, and potential side effects, with limited success in improving obesity through increased energy expenditure. This study explores the potential of a refined sulfated polysaccharide (SPSL), derived from the brown seaweed Scytosiphon lomentaria (SL), as a safe and effective anti-obesity treatment by promoting energy expenditure. Chemical characterization revealed that SPSL, rich in sulfate and L-fucose content, comprises nine distinct sulfated glycan structures. In vitro analysis demonstrated potent anti-lipogenic properties in adipocytes, mediated by the downregulation of key adipogenic modulators, including 5' adenosine monophosphate-activated protein kinase (AMPK) and peroxisome proliferator-activated receptor γ (PPARγ) pathways. Inhibiting AMPK attenuated the anti-adipogenic effects of SPSL, confirming its involvement in the mechanism of action. Furthermore, in vivo studies using zebrafish models showed that SPSL increased energy expenditure and reduced lipid accumulation. These findings collectively highlight the therapeutic potential of SPSL as a functional food ingredient for mitigating obesity-related metabolic dysregulation by promoting energy expenditure. Further mechanistic and preclinical investigations are warranted to fully elucidate its mode of action and evaluate its efficacy in obesity management, potentially offering a novel, natural therapeutic avenue for this global health concern.

Ketogenic diet with aerobic exercise can induce fat browning: potential roles of β-hydroxybutyrate

Introduction

Despite evidence suggesting that metabolic intermediates like β-HB influence white adipose tissue (WAT) metabolism, the precise molecular mechanisms remain unclear. The aim of this study was to investigate the impact of beta-hydroxybutyrate (β-HB) on the fat browning program and to explore the underlying molecular mechanisms using both in vitro and in vivo models. We assessed the effects of β-HB on fat browning in adipocytes using 3T3-L1 cells and rat models.

Methods

We evaluated the effects of β-HB on fat browning, thermogenesis, lipid accumulation, adipokine expression, and mitochondrial biogenesis by treating mature 3T3-L1 adipocytes with sodium β-HB for 24 h or by continuously exposing preadipocytes to β-HB during the 8-day differentiation process. Male Sprague Dawley rats were divided into control, exercise only (EX), ketogenic diet only (KD), and combined exercise and ketogenic diet (KE) groups for an 8-week intervention involving diet and/or exercise. After intervention, we evaluated WAT histology, plasma lipids and adipokines, and the expression of markers related to fat browning, thermogenesis and mitochondrial biogenesis in WAT of rats.

Results

In our adipocyte culture experiments, β-HB reduced intracellular lipid accumulation by enhancing lipolysis and stimulated the expression of thermogenic and fat browning genes like uncoupling protein 1 (UCP1), PR domain containing 16 (PRDM16), and adipokines such as fibroblast growth factor 21 (FGF21) and Fibronectin type III domain-containing protein 5 (FDNC5). Additionally, β-HB activated the AMPK-SIRT1-PGC-1α pathway, with UCP1 and PRDM16 upregulation mediated by β-HB intracellular action and SIRT1 activity. In animal experiments, KE group raised β-HB levels, decreasing body weight and blood lipids. KD with EX promoted WAT browning possibly via AMPK-SIRT1-PGC-1α, augmenting PRDM16, UCP1, FGF21, and FNDC5 expression.

Conclusion

β-HB induction via KD and/or EX shows potential in promoting WAT browning by activating mitochondrial biogenesis, lipolysis, and thermogenesis, suggesting that dietary and physical intervention inducing β-HB may benefit metabolic health.

Exploring the anti-obesity effects of kimchi through enhanced thermogenesis in differentiated T37i brown adipocytes

Background

Previous research has demonstrated the anti-obesity effects of kimchi in 3T3-L1 adipocytes and mice with diet-induced obesity by assessing the expression of obesity-associated genes. Additionally, recent studies have identified mechanisms involving thermogenesis that support these effects.

Objective

This study aims to further investigate the anti-obesity properties of kimchi, focusing on its impact on thermogenic activity in differentiated T37i brown adipocytes.

Design

The study first evaluated the antioxidant potential of kimchi using total antioxidant capacity (TAC) and ferric reducing antioxidant power (FRAP) assays. Optimal differentiation conditions for T37i adipocytes were established before proceeding with evaluations of cell viability, intracellular triglyceride (TG) content, lipid accumulation, and the expression of genes and proteins related to obesity and thermogenesis.

Results

Kimchi maintained over 90% cell viability in T37i adipocytes at concentrations up to 1,000 μg/mL. Efficient differentiation of T37i preadipocytes was achieved using a medium containing 10% calf serum, 2 nM 3,3',5-triiodo-L-thyronin (T3), and 100 nM insulin. Kimchi significantly reduced intracellular TG levels and lipid accumulation, compared to the control group, and enhanced the expression of genes and proteins related to thermogenesis while reducing the expression of obesity-related genes.

Discussion

The findings suggest that kimchi exerts its anti-obesity effects by modulating thermogenic and obesity-related pathways in brown adipocytes, which may be partially attributed to its antioxidant properties.

Conclusions

Kimchi shows promise as a preventive measure against obesity by influencing metabolic pathways associated with both obesity and thermogenesis in T37i brown adipocytes.

Nootkatone (NK), a grapefruit-derived aromatic compound, inhibited lipid accumulation by regulating JAK2-STAT signaling and antioxidant response in adipocyte

Nootkatone (NK) is an aromatic compound derived from grapefruit. This study aimed to investigate the inhibitory effect of NK on lipid accumulation and its underlying mechanism in adipocytes. NK effectively inhibited adipogenic lipid storage by downregulating C/EBPα and PPARγ, while upregulating KLF2, an early inhibitory factor, downregulating C/EBPβ, an early promoting factor. In addition, NK inhibited the JAK2-STAT signaling pathway by decreasing the phosphorylation of STAT3 and STAT5 in the early adipogenic stage. NK significantly reduced ROS generation while elevating antioxidant enzymes such as catalase and glutathione peroxidase. It activated NRF2-HO-1 signaling, responsible for antioxidant response, by increasing protein levels. Furthermore, NK regulated adipokines, increasing adiponectin and visfatin, while downregulating resistin. Collectively, NK inhibited adipogenic lipid accumulation through the suppression of JAK2-STAT signaling and the augmentation of antioxidant response. This study highlights the potential of NK as an edible agent to alleviate obesity and its associated metabolic diseases.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-024-01522-2.

Novel insights into regulators and functional modulators of adipogenesis

Adipogenesis is a process that differentiates new adipocytes from precursor cells and is tightly regulated by several factors, including many transcription factors and various post-translational modifications. Recently, new roles of adipogenesis have been suggested in various diseases. However, the molecular mechanisms and functional modulation of these adipogenic genes remain poorly understood. This review summarizes the regulatory factors and modulators of adipogenesis and discusses future research directions to identify novel mechanisms regulating adipogenesis and the effects of adipogenic regulators in pathological conditions. The master adipogenic transcriptional factors PPARγ and C/EBPα were identified along with other crucial regulatory factors such as SREBP, Kroxs, STAT5, Wnt, FOXO1, SWI/SNF, KLFs, and PARPs. These transcriptional factors regulate adipogenesis through specific mechanisms, depending on the adipogenic stage. However, further studies related to the in vivo role of newly discovered adipogenic regulators and their function in various diseases are needed to develop new potent therapeutic strategies for metabolic diseases and cancer.

Medicinal Plant Extracts against Cardiometabolic Risk Factors Associated with Obesity: Molecular Mechanisms and Therapeutic Targets

Obesity has increasingly become a worldwide epidemic, as demonstrated by epidemiological and clinical studies. Obesity may lead to the development of a broad spectrum of cardiovascular diseases (CVDs), such as coronary heart disease, hypertension, heart failure, cerebrovascular disease, atrial fibrillation, ventricular arrhythmias, and sudden cardiac death. In addition to hypertension, there are other cardiometabolic risk factors (CRFs) such as visceral adiposity, dyslipidemia, insulin resistance, diabetes, elevated levels of fibrinogen and C-reactive protein, and others, all of which increase the risk of CVD events. The mechanisms involved between obesity and CVD mainly include insulin resistance, oxidative stress, inflammation, and adipokine dysregulation, which cause maladaptive structural and functional alterations of the heart, particularly left-ventricular remodeling and diastolic dysfunction. Natural products of plants provide a diversity of nutrients and different bioactive compounds, including phenolics, flavonoids, terpenoids, carotenoids, anthocyanins, vitamins, minerals, fibers, and others, which possess a wide range of biological activities including antihypertensive, antilipidemic, antidiabetic, and other activities, thus conferring cardiometabolic benefits. In this review, we discuss the main therapeutic interventions using extracts from herbs and plants in preclinical and clinical trials with protective properties targeting CRFs. Molecular mechanisms and therapeutic targets of herb and plant extracts for the prevention and treatment of CRFs are also reviewed.

Deletion of adipocyte Sine Oculis Homeobox Homolog 1 prevents lipolysis and attenuates skin fibrosis

Dermal fibrosis is a cardinal feature of systemic sclerosis (SSc) for which there are limited treatment strategies. This is in part due to our fragmented understanding of how dermal white adipose tissue (DWAT) contributes to skin fibrosis. We identified elevated sine oculis homeobox homolog 1 (SIX1) expression in SSc skin samples from the GENISOS and PRESS cohorts, the expression of which correlated with adipose-associated genes and molecular pathways. SIX1 localization studies identified increased signals in the DWAT area in SSc and in experimental models of skin fibrosis. Global and adipocyte specific Six1 deletion abrogated end-stage fibrotic gene expression and dermal adipocyte shrinkage induced by SQ bleomycin treatment. Further studies revealed a link between elevated SIX1 and increased expression of SERPINE1 and its protein PAI-1 which are known pro-fibrotic mediators. However, SIX1 deletion did not appear to affect cellular trans differentiation. Taken together these results point at SIX1 as a potential target for dermal fibrosis in SSc.

Quinoa Polyphenol Extract Alleviates Non-Alcoholic Fatty Liver Disease via Inhibiting Lipid Accumulation, Inflammation and Oxidative Stress

Recently, the incidence of NAFLD has exploded globally, but there are currently no officially approved medications for treating the condition. The regulation of NAFLD through plant-derived active substances has become a new area of interest. Quinoa (Chenopodium quinoa Willd.) has been discovered to contain a large quantity of bioactive compounds. In this study, we established a free fatty acid (FFA)-induced steatosis model and explored the effects of quinoa polyphenol extract (QPE) on the major hallmarks of NAFLD. The results indicated that QPE significantly reduced intracellular triglyceride (TG) and total cholesterol (TC) levels. Additionally, QPE remarkably elevated the levels of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) and lowered levels of malondialdehyde (MDA). Further examination revealed that QPE attenuated intracellular inflammation, which was verified by the reduced levels of pro-inflammatory cytokines. Mechanistically, QPE inhibited fatty acid biosynthesis mainly by targeting de novo lipogenesis (DNL) via the AMPK/SREBP-1c signaling pathway. Moreover, network pharmacology was used to analyze key targets for NAFLD mitigation by ferulic acid (FA), a major component of QPE. Taken together, this study suggests that QPE could ameliorate NAFLD by modulating hepatic lipid metabolism and alleviating oxidative stress and inflammation.

Kaempferia parviflora extract and its component polymethoxyflavones suppress adipogenic differentiation of human bone marrow-derived mesenchymal stem cells via the AMPK pathway

BACKGROUND

Kaempferia parviflora Wall. ex. Baker (KP) has been reported to exhibit anti-obesity effects. However, the detailed mechanism of the anti-obesity effect of KP extract (KPE) is yet to be clarified. Here, we investigated the effect of KPE and its component polymethoxyflavones (PMFs) on the adipogenic differentiation of human mesenchymal stem cells (MSCs).

METHODS AND RESULTS

KPE and PMFs fraction (2.5 µg/mL) significantly inhibited lipid and triacylglyceride accumulation in MSCs; lipid accumulation in MSCs was suppressed during the early stages of differentiation (days 0-3) but not during the mid (days 3-7) or late (days 7-14) stages. Treatment with KPE and PMFs fractions significantly suppressed peroxisome proliferator-activated receptor-γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), and various adipogenic metabolic factors. Treatment with KPE and PMFs fraction induced the activation of AMP-activated protein kinase (AMPK) signaling, and pretreatment with an AMPK signaling inhibitor significantly attenuated KPE- and PMFs fraction-induced suppression of lipid formation.

CONCLUSIONS

Our findings demonstrate that KPE and PMFs fraction inhibit lipid formation by inhibiting the differentiation of undifferentiated MSCs into adipocyte lineages via AMPK signaling, and this may be the mechanism underlying the anti-obesity effects of KPE and PMFs. Our study lays the foundation for the elucidation of the anti-obesity mechanism of KPE and PMFs.

Novel perspectives on autophagy-oxidative stress-inflammation axis in the orchestration of adipogenesis

Adipose tissue, an indispensable organ, fulfils the pivotal role of energy storage and metabolism and is instrumental in maintaining the dynamic equilibrium of energy and health of the organism. Adipocyte hypertrophy and adipocyte hyperplasia (adipogenesis) are the two primary mechanisms of fat deposition. Mature adipocytes are obtained by differentiating mesenchymal stem cells into preadipocytes and redifferentiation. However, the mechanisms orchestrating adipogenesis remain unclear. Autophagy, an alternative cell death pathway that sustains intracellular energy homeostasis through the degradation of cellular components, is implicated in regulating adipogenesis. Furthermore, adipose tissue functions as an endocrine organ, producing various cytokines, and certain inflammatory factors, in turn, modulate autophagy and adipogenesis. Additionally, autophagy influences intracellular redox homeostasis by regulating reactive oxygen species, which play pivotal roles in adipogenesis. There is a growing interest in exploring the involvement of autophagy, inflammation, and oxidative stress in adipogenesis. The present manuscript reviews the impact of autophagy, oxidative stress, and inflammation on the regulation of adipogenesis and, for the first time, discusses their interactions during adipogenesis. An integrated analysis of the role of autophagy, inflammation and oxidative stress will contribute to elucidating the mechanisms of adipogenesis and expediting the exploration of molecular targets for treating obesity-related metabolic disorders.

Anti-Obesity Effect of Lactobacillus acidophilus DS0079 (YBS1) by Inhibition of Adipocyte Differentiation through Regulation of p38 MAPK/PPARγ Signaling

Obesity is spawned by an inequality between the portion of energy consumed and the quantity of energy expended. Disease entities such as cardiovascular disease, arteriosclerosis, hypertension, and cancer, which are correlated with obesity, influence society and the economy. Suppression of adipogenesis, the process of white adipocyte generation, remains a promising approach for treating obesity. Oil Red O staining was used to differentiate 3T3-L1 cells for screening 20 distinct Lactobacillus species. Among these, Lactobacillus acidophilus DS0079, referred to as YBS1, was selected for further study. YBS1 therapy decreased 3T3-L1 cell development. Triglyceride accumulation and mRNA expression of the primary adipogenic marker, peroxisome proliferator-activated receptor gamma (PPARγ), including its downstream target genes, adipocyte fatty acid binding protein 4 and adiponectin, were almost eliminated. YBS1 inhibited adipocyte differentiation at the early stage (days 0-2), but no significant difference was noted between the mid-stage (days 2-4) and late-stage (days 4-6) development. YBS1 stimulated the activation of p38 mitogen-activated protein kinase (p38 MAPK) during the early stages of adipogenesis; however, this effect was eliminated by the SB203580 inhibitor. The data showed that YBS1 administration inhibited the initial development of adipocytes via stimulation of the p38 MAPK signaling pathway, which in turn controlled PPARγ expression. In summary, YBS1 has potential efficacy as an anti-obesity supplement and requires further exploration.

AMPK as a mediator of tissue preservation: time for a shift in dogma?

Ground-breaking discoveries have established 5'-AMP-activated protein kinase (AMPK) as a central sensor of metabolic stress in cells and tissues. AMPK is activated through cellular starvation, exercise and drugs by either directly or indirectly affecting the intracellular AMP (or ADP) to ATP ratio. In turn, AMPK regulates multiple processes of cell metabolism, such as the maintenance of cellular ATP levels, via the regulation of fatty acid oxidation, glucose uptake, glycolysis, autophagy, mitochondrial biogenesis and degradation, and insulin sensitivity. Moreover, AMPK inhibits anabolic processes, such as lipogenesis and protein synthesis. These findings support the notion that AMPK is a crucial regulator of cell catabolism. However, studies have revealed that AMPK's role in cell homeostasis might not be as unidirectional as originally thought. This Review explores emerging evidence for AMPK as a promoter of cell survival and an enhancer of anabolic capacity in skeletal muscle and adipose tissue during catabolic crises. We discuss AMPK-activating interventions for tissue preservation during tissue wasting in cancer-associated cachexia and explore the clinical potential of AMPK activation in wasting conditions. Overall, we provide arguments that call for a shift in the current dogma of AMPK as a mere regulator of cell catabolism, concluding that AMPK has an unexpected role in tissue preservation.

Autophagic Regulation of Adipogenesis Through TP53INP2: Insights from In Silico and In Vitro Analysis

Obesity is an epidemic disease associated with multimorbidity resulting in higher mortality risk. The imbalance between energy storage and expenditure is the prime factor in the prognosis of the disease. Specifically, excessive lipid storage through adipogenesis leads to obesity. Adipogenesis is the process that converts preadipocytes into mature adipocytes by regulating major transcription factors like PPARγ and C/EBPα, contributes to lipid storage in adipose tissue. On the contrary, autophagy is a self-degradative process that maintains homeostasis in adipose tissue by regulating adipogenesis and lipolysis. TP53INP2 is a key player that regulates the autophagy process, and it negatively regulates adipogenesis and lipid storage. The gene expression profile GSE93637 was retrieved from the GEO database and analyzed using an integrated bioinformatics approach. The differentially expressed genes (DEGs) were analyzed using R-Bioconductor for TP53INP2 knockdown microarray dataset of 3T3L1 cells, and the DEGs were analyzed for the functional enrichment analysis. Further, the genes involved in the potential biological and molecular functions were evaluated for pathway enrichment analysis by KEGG (Kyoto Encyclopedia of Genes and Genomes). A total of 726 DEGs were found including 391 upregulated and 335 downregulated genes. Further, the functional and pathway enrichment analysis was employed to identify the highly interacting genes, and we identified a total of 56 genes that are highly interacting through a protein-protein interaction network. The DEGs mainly regulate the Peroxisome proliferator-activated receptor (PPAR) signaling pathway, lipolysis, and autophagy. Further, we investigated the associated Hub genes for enriched pathway genes and found the involvement of two autophagic genes ATG7 and sequestosome 1 (p62). In addition, in vitro studies of qRT-PCR (Quantitative real-time polymerase chain reaction) and Western blot analysis revealed that increased autophagy resulted in reduced lipid storage through down-regulation of the adipogenic gene. Moreover, increased expression of autophagic gene TP53INP2 and ATG7 facilitates the down-regulation of p62 and PPARγ gene resulting in lipolysis in mature adipocytes through autophagy. There is no specific treatment to reduce obesity other than a caloric diet and exercise. Hence, this study provides sufficient evidence to conclude that TP53INP2 negatively regulates adipogenesis and increases the degradation of lipids in mature adipocytes which is crucial for reducing obesity. Therefore, it is plausible to consider TP53INP2 as a promising therapeutic target for managing adipogenesis and obesity. However, further studies are necessary to validate their functional and molecular pathway analysis in the regulation of adipogenesis and obesity.

Constructing eRNA-mediated gene regulatory networks to explore the genetic basis of muscle and fat-relevant traits in pigs

BACKGROUND

Enhancer RNAs (eRNAs) play a crucial role in transcriptional regulation. While significant progress has been made in understanding epigenetic regulation mediated by eRNAs, research on the construction of eRNA-mediated gene regulatory networks (eGRN) and the identification of critical network components that influence complex traits is lacking.

RESULTS

Here, employing the pig as a model, we conducted a comprehensive study using H3K27ac histone ChIP-seq and RNA-seq data to construct eRNA expression profiles from multiple tissues of two distinct pig breeds, namely Enshi Black (ES) and Duroc. In addition to revealing the regulatory landscape of eRNAs at the tissue level, we developed an innovative network construction and refinement method by integrating RNA-seq, ChIP-seq, genome-wide association study (GWAS) signals and enhancer-modulating effects of single nucleotide polymorphisms (SNPs) measured by self-transcribing active regulatory region sequencing (STARR-seq) experiments. Using this approach, we unraveled eGRN that significantly influence the growth and development of muscle and fat tissues, and identified several novel genes that affect adipocyte differentiation in a cell line model.

CONCLUSIONS

Our work not only provides novel insights into the genetic basis of economic pig traits, but also offers a generalizable approach to elucidate the eRNA-mediated transcriptional regulation underlying a wide spectrum of complex traits for diverse organisms.

AMP-activated protein kinase activation suppresses leptin expression independently of adipogenesis in primary murine adipocytes

Adipogenesis, defined as the development of mature adipocytes from stem cell precursors, is vital for the expansion, turnover and health of adipose tissue. Loss of adipogenic potential in adipose stem cells, or impairment of adipogenesis is now recognised as an underlying cause of adipose tissue dysfunction and is associated with metabolic disease. In this study, we sought to determine the role of AMP-activated protein kinase (AMPK), an evolutionarily conserved master regulator of energy homeostasis, in adipogenesis. Primary murine adipose-derived stem cells were treated with a small molecule AMPK activator (BI-9774) during key phases of adipogenesis, to determine the effect of AMPK activation on adipocyte commitment, maturation and function. To determine the contribution of the repression of lipogenesis by AMPK in these processes, we compared the effect of pharmacological inhibition of acetyl-CoA carboxylase (ACC). We show that AMPK activation inhibits adipogenesis in a time- and concentration-dependent manner. Transient AMPK activation during adipogenic commitment leads to a significant, ACC-independent, repression of adipogenic transcription factor expression. Furthermore, we identify a striking, previously unexplored inhibition of leptin gene expression in response to both short-term and chronic AMPK activation irrespective of adipogenesis. These findings reveal that in addition to its effect on adipogenesis, AMPK activation switches off leptin gene expression in primary mouse adipocytes independently of adipogenesis. Our results identify leptin expression as a novel target of AMPK through mechanisms yet to be identified.

Vitamin D and obesity

An inverse association between vitamin D status and obesity has been reported across diverse populations and age groups in humans. In animal model of diet-induced obesity, dysregulation of vitamin D metabolism has been observed. However, the causal relationship between vitamin D status and obesity is not conclusive. Several explanations, such as volumetric dilution, sequestration of vitamin D into adipose tissue, and limited sunlight exposure, have been suggested as the underlying mechanisms linking poor vitamin D status and obesity. Vitamin D can modulate adipose tissue biology, spanning from adipocyte differentiation to adipocyte apoptosis and energy metabolism, indicating its potential impact on adiposity. In this chapter, we will review the prevalence of vitamin D deficiency and determinants of vitamin D deficiency among different populations, as well as changes in vitamin D metabolism associated with obesity. Additionally, we will review vitamin D's regulation of adipogenesis and lipogenesis at the cellular level in order to gain a deeper understanding of the underlying mechanisms linking vitamin D levels and obesity.

Sesamin and sesamolin potentially inhibit adipogenesis through downregulating the peroxisome proliferator-activated receptor γ protein expression and activity in 3T3-L1 cells

Sesamin and sesamolin are major sesame lignans that have demonstrated anti-inflammatory, anticancer, and neuroprotective properties and potential benefits in the liver, cardiovascular diseases, and metabolic syndrome. However, despite previous research on their antiobesity effects and underlying mechanisms, a comprehensive investigation of these aspects is still lacking. In this study, we evaluated the regulatory effects of 20 to 80 µM sesamin and sesamolin on adipogenesis in vitro using 3T3-L1 cells as a model cell line. We hypothesized that the lignans would inhibit adipogenic differentiation in 3T3-L1 cells through the regulation of peroxisome proliferator-activated receptor γ (PPARγ). Our data indicate that sesamin and sesamolin inhibited the adipogenic differentiation of 3T3-L1 cells by dose-dependently decreasing lipid accumulation and triglyceride formation. Sesamin and sesamolin reduced the mRNA and protein expression of the adipogenesis-related transcription factors, PPARγ and CCAAT/enhancer-binding protein α, leading to the dose-dependent downregulations of their downstream targets, fatty acid binding protein 4, hormone-sensitive lipase, lipoprotein lipase, and glucose transporter 4. In addition, glucose uptake was dose-dependently attenuated by sesamin and sesamolin in both differentiated 3T3-L1 cells and HepG2 cells. Interestingly, our results suggested that sesamin and sesamolin might directly bind to PPARγ to inhibit its transcriptional activity. Finally, sesamin and sesamolin decreased the phosphorylation of 3 mitogen-activated protein kinase signaling components in differentiated 3T3-L1 cells. Taken together, our findings suggest that sesamin and sesamolin may exhibit antiobesity effects by potentially downregulating PPARγ and its downstream genes through the mitogen-activated protein kinase signaling pathway, offering important insights into the molecular mechanisms underlying the potential antiobesity effects of sesamin and sesamolin.

The serine protease 2 gene regulates lipid metabolism through the LEP/ampkα1/SREBP1 pathway in bovine mammary epithelial cells

Molecular breeding has brought about significant transformations in the milk market and production system during the twenty-first century. The primary economic characteristic of dairy production pertains to milk fat content. Our previous transcriptome analyses revealed that serine protease 2 (PRSS2) is a candidate gene that could impact milk fat synthesis in bovine mammary epithelial cells (BMECs) of Chinese Holstein dairy cows. To elucidate the function of the PRSS2 gene in milk fat synthesis, we constructed vectors for PRSS2 overexpression and interference and assessed intracellular triglycerides (TGs), cholesterol (CHOL), and nonesterified fatty acid (NEFA) contents in BMECs. Fatty acid varieties and components were also quantified using gas chromatography‒mass spectrometry (GC‒MS) technology. The regulatory pathway mediated by PRSS2 was validated through qPCR, ELISA, and WB techniques. Based on our research findings, PRSS2 emerges as a pivotal gene that regulates the expression of associated genes, thereby making a substantial contribution to lipid metabolism via the leptin (LEP)/Adenylate-activated protein kinase, alpha 1 catalytic subunit (AMPKα1)/sterol regulatory element binding protein 1(SREBP1) pathway by inhibiting TGs and CHOL accumulation while potentially promoting NEFA synthesis in BMECs. Furthermore, the PRSS2 gene enhances intracellular medium- and long-chain fatty acid metabolism by modulating genes related to the LEP/AMPKα1/SREBP1 pathway, leading to increased contents of unsaturated fatty acids C17:1N7 and C22:4N6. This study provides a robust theoretical framework for further investigation into the underlying molecular mechanisms through which PRSS2 influences lipid metabolism in dairy cows.

Facile adipocyte uptake and liver/adipose tissue delivery of conjugated linoleic acid-loaded tocol nanocarriers for a synergistic anti-adipogenesis effect

Obesity is a major risk to human health. Adipogenesis is blocked by α-tocopherol and conjugated linoleic acid (CLA). However, their effect at preventing obesity is uncertain. The effectiveness of the bioactive agents is associated with their delivery method. Herein, we designed CLA-loaded tocol nanostructured lipid carriers (NLCs) for enhancing the anti-adipogenic activity of α-tocopherol and CLA. Adipogenesis inhibition by the nanocarriers was examined using an in vitro adipocyte model and an in vivo rat model fed a high fat diet (HFD). The targeting of the tocol NLCs into adipocytes and adipose tissues were also investigated. A synergistic anti-adipogenesis effect was observed for the combination of free α-tocopherol and CLA. Nanoparticles with different amounts of solid lipid were developed with an average size of 121‒151 nm. The NLCs with the smallest size (121 nm) showed greater adipocyte internalization and differentiation prevention than the larger size. The small-sized NLCs promoted CLA delivery into adipocytes by 5.5-fold as compared to free control. The nanocarriers reduced fat accumulation in adipocytes by counteracting the expression of the adipogenic transcription factors peroxisome proliferator activated receptor (PPAR)γ and CCAAT/enhancer-binding protein (C/EBP)α, and lipogenic enzymes acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS). Localized administration of CLA-loaded tocol NLCs significantly reduced body weight, total cholesterol, and liver damage indicators in obese rats. The biodistribution study demonstrated that the nanoparticles mainly accumulated in liver and adipose tissues. The NLCs decreased adipocyte hypertrophy and cytokine overexpression in the groin and epididymis to a greater degree than the combination of free α-tocopherol and CLA. In conclusion, the lipid-based nanocarriers were verified to inhibit adipogenesis in an efficient and safe way.

Drynaria rhizome water extract alleviates high‑fat diet‑induced obesity in mice

Drynaria rhizome is a herbal medicine used for strengthening bones and treating bone diseases in East Asia. Although obesity is considered to benefit bone formation, it has been revealed that visceral fat accumulation can promote osteoporosis. Given the complex relationship between bone metabolism and obesity, bone‑strengthening medicines should be evaluated while considering the effects of obesity. The present study investigated the effects of Drynaria rhizome extract (DRE) on high‑fat diet (HFD)‑induced obese mice. DRE was supplemented with the HFD. Body weight, food intake, the expression levels of lipogenesis transcription factors, including sterol regulatory element binding protein (SREBP)‑1, peroxisome proliferator‑activated receptor (PPAR)‑γ and adenosine monophosphate‑activated protein kinase (AMPK)‑α, and AMPK activation were evaluated. Mice fed DRE and a HFD exhibited reduced body weight without differences in food intake compared with those in the HFD group. Furthermore, DRE; upregulated AMPK‑α of epididymal one; down‑regulated SREBP‑1 and PPAR‑γ, as determined using western blotting and quantitative polymerase chain reaction, respectively. Decreased lipid accumulation were observed in both fat pad and liver of HFD‑fed mice, which were suppressed by DRE treatment. These results demonstrated the potential of DRE as a dietary natural product for strengthening bones and managing obesity.

Cinnamyl Alcohol Attenuates Adipogenesis in 3T3-L1 Cells by Arresting the Cell Cycle

Cinnamyl alcohol (CA) is an aromatic compound found in several plant-based resources and has been shown to exert anti-inflammatory and anti-microbial activities. However, the anti-adipogenic mechanism of CA has not been sufficiently studied. The present study aimed to investigate the effect and mechanism of CA on the regulation of adipogenesis. As evidenced by Oil Red O staining, Western blotting, and real-time PCR (RT-PCR) analyses, CA treatment (6.25-25 μM) for 8 d significantly inhibited lipid accumulation in a concentration-dependent manner and downregulated adipogenesis-related markers (peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding protein α (C/EBPα), fatty acid binding protein 4 (FABP4), adiponectin, fatty acid synthase (FAS)) in 3-isobutyl-1-methylxanthine, dexamethasone, and insulin(MDI)-treated 3T3-L1 adipocytes. In particular, among the various differentiation stages, the early stage of adipogenesis was critical for the inhibitory effect of CA. Cell cycle analysis using flow cytometry and Western blotting showed that CA effectively inhibited MDI-induced initiation of mitotic clonal expansion (MCE) by arresting the cell cycle in the G0/G1 phase and downregulating the expression of C/EBPβ, C/EBPδ, and cell cycle markers (cyclin D1, cyclin-dependent kinase 6 (CDK6), cyclin E1, CDK2, and cyclin B1). Moreover, AMP-activated protein kinase α (AMPKα), acetyl-CoA carboxylase (ACC), and extracellular signal-regulated kinase 1/2 (ERK1/2), markers of upstream signaling pathways, were phosphorylated during MCE by CA. In conclusion, CA can act as an anti-adipogenic agent by inhibiting the AMPKα and ERK1/2 signaling pathways and the cell cycle and may also act as a potential therapeutic agent for obesity.

Thymoquinone mitigates obesity and diabetic parameters through regulation of major adipokines, key lipid metabolizing enzymes and AMPK/p-AMPK in diet-induced obese rats

The present study was designed to evaluate the anti-obesity and anti-hyperglycemic activity of Thymoquinone (ThyQ) isolated from Nigella sativa seeds. Male Wistar rats were randomly divided into five groups and fed either normal pellet diet or high-fat diet (HFD) for 18 weeks and water ad-libitum. Group I: normal pellet diet (NPD)-fed, Group II: high-fat diet (HFD)-fed, Group III: HFD-fed-ThyQ (20 mg)-treated, Group IV: HFD-fed-ThyQ (40 mg)-treated and Group V: HFD-fed-Orlistat (5 mg)-treated group. Intervention with ThyQ started from 12th week onwards to HFD-fed rats of group III and IV. ThyQ administration significantly (p < 0.01) mitigated body weight gain, blood glucose, insulin level, serum and liver lipids (except HDL) and improved glucose tolerance and insulin sensitivity as evaluated by oral glucose tolerance test (OGTT), homeostasis model assessment-insulin resistance (HOMA-IR) and insulin tolerance test (ITT). Furthermore, ThyQ significantly (p < 0.01) diminished serum aspartate transaminase (AST), alanine transaminase (ALT), acetyl-CoA carboxylase (ACC), plasma leptin, resistin and visfatin levels but enhanced lipoprotein lipase (LPL) and adiponectin levels. RT-PCR analysis demonstrated down-regulated mRNA expression of sterol regulatory element-binding proteins-1c (SREBP-1c), CCAAT/enhancer-binding protein-α (C/EBP-α) and fatty acid synthase (FAS) but upregulation of Insulin receptor substrate-1 (IRS-1).Western blot analysis displayed phosphorylation of adenosine monophosphate activated protein kinase (AMPK) in ThyQ-treated rats. Liver microtome sections of HFD-fed rats showed degenerated hepatocytes with high lipid stores while that of adipose tissue sections displayed large, fat-laden adipocytes, however, these histological changes were considerably attenuated in ThyQ-treated groups. Together these findings demonstrate that ThyQ can be a valuable therapeutic compound to potentially alleviate diet-induced obesity, hyperglycemia and insulin resistance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03847-x.

LncRNA U90926 is dispensable for the development of obesity-associated phenotypes in vivo

Obesity is a global health problem characterized by excessive fat accumulation, driven by adipogenesis and lipid accumulation. Long non-coding RNAs (lncRNAs) have recently been implicated in regulating adipogenesis and adipose tissue function. Mouse lncRNA U90926 was previously identified as a repressor of in vitro adipogenesis in 3T3-L1 preadipocytes. Consequently, we hypothesized that, in vivo, U90926 may repress adipogenesis, and hence its deletion would increase weight gain and adiposity. We tested the hypothesis by applying U90926-deficient (U9-KO) mice to a high-throughput phenotyping pipeline. Compared with WT, U9-KO mice showed no major differences across a wide range of behavioral, neurological, and other physiological parameters. In mice fed a standard diet, we have found no differences in obesity-related phenotypes, including weight gain, fat mass, and plasma concentrations of glucose, insulin, triglycerides, and free fatty acids, in U9-KO mice compared to WT. U90926 deficiency lacked a major effect on white adipose tissue morphology and gene expression profile. Furthermore, in mice fed a high-fat diet, we found increased expression of U90926 in adipose tissue stromal vascular cell fraction, yet observed no effect of U90926 deficiency on weight gain, fat mass, adipogenesis marker expression, and immune cell infiltration into the adipose tissue. These data suggest that the U90926 lacks an essential role in obesity-related phenotypes and adipose tissue biology in vivo.

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.

Dietary flaxseed oil induces production of adiponectin in visceral fat and prevents obesity in mice

Induction of obesity by dietary fats and oils differs according to the type of fat. Adiponectin is believed to be related to obesity prevention. We hypothesized that flaxseed oil is important for preventing obesity and producing adiponectin. To clarify this hypothesis, we investigated the relationship between obesity and different fat sources in mice fed diets with 6 types of fat and oils. C57BL/6J mice were given a control diet containing 5% corn oil or a high-fat diet containing 20% of either lard, palm oil, rapeseed oil, oleate-rich safflower oil, corn oil, or flaxseed oil for 14 weeks. In another experiment, mice were given a control diet and rosiglitazone (10 mg/kg body weight) by oral gavage for 1 week. At the end of study, plasma adiponectin and expression of fatty acid metabolism-related factors in white and brown adipose tissue and the liver were measured. Dietary flaxseed oil, which is rich in α-linolenic acid, did not induce obesity. Flaxseed oil resulted in increased β-oxidation-related factors in epididymal white adipose tissue, decreased fatty acid synthesis-related factors in the liver, and thermogenesis-related factor in brown adipose tissue following increase of plasma adiponectin. The results suggested that increase in plasma adiponectin after intake of flaxseed oil may be due to altered expression of AdipoQ and peroxisome proliferator-activated receptor γ in epididymal white adipose tissue. Flaxseed oil increased expression of adiponectin in visceral fat and regulated obesity-controlling fatty acid metabolism-related factors in white adipose tissue and liver, and thermogenesis-related factor in brown adipose tissue.

BMP8B Activates Both SMAD2/3 and NF-κB Signals to Inhibit the Differentiation of 3T3-L1 Preadipocytes into Mature Adipocytes

Bone morphogenetic protein 8B (BMP8B) has been found to regulate the thermogenesis of brown adipose tissue (BAT) and the browning process of white adipose tissue (WAT). However, there is no available information regarding the role of BMP8B in the process of adipocyte differentiation. Here, we showed that BMP8B down-regulates transcriptional regulators PPARγ and C/EBPα, thereby impeding the differentiation of 3T3-L1 preadipocytes into fully mature adipocytes. BMP8B increased the phosphorylation levels of SMAD2/3, and TP0427736 HCl (SMAD2/3 inhibitor) significantly reduced the ability of BMP8B to inhibit adipocyte differentiation, suggesting that BMP8B repressed adipocyte differentiation through the SMAD2/3 pathway. Moreover, the knockdown of BMP I receptor ALK4 significantly reduced the inhibitory effect of BMP8B on adipogenesis, indicating that BMP8B triggers SMAD2/3 signaling to suppress adipogenesis via ALK4. In addition, BMP8B activated the NF-κB signal, which has been demonstrated to impede PPARγ expression. Collectively, our data demonstrated that BMP8B activates both SMAD2/3 and NF-κB signals to inhibit adipocyte differentiation. We provide previously unidentified insight into BMP8B-mediated adipogenesis.

Inhibitory Effects of Sesquiterpenoids Isolated from Artemisia scoparia on Adipogenic Differentiation of 3T3-L1 Preadipocytes

Obesity and related complications are significant health issues in modern society, largely attributed to a sedentary lifestyle and a carbohydrate-rich diet. Since anti-obesity drugs often come with severe side effects, preventative measures are being sought globally, including dietary changes and functional foods that can counteract weight gain. In this context, plant-based metabolites are extensively studied for their advantageous biological effects against obesity. Several plants within the Artemisia genus have been reported to possess anti-adipogenic properties, preventing adipocytes from maturing and accumulating lipids. The present study investigated the anti-adipogenic potential of two sesquiterpenoids, reynosin and santamarine, isolated from A. scoparia in adipose-induced 3T3-L1 preadipocytes. Differentiating 3T3-L1 adipocytes treated with these isolated compounds displayed fewer adipogenic characteristics compared to untreated mature adipocytes. The results indicated that cells treated with reynosin and santamarine accumulated 55.0% and 52.5% fewer intracellular lipids compared to untreated control adipocytes, respectively. Additionally, the mRNA expression of the key adipogenic marker, transcription factor PPARγ, was suppressed by 87.2% and 91.7% following 60 μM reynosin and santamarine treatment, respectively, in differentiated adipocytes. Protein expression was also suppressed in a similar manner, at 92.7% and 82.5% by 60 μM reynosin and santamarine treatment, respectively. Likewise, SERBP1c and C/EBPα were also downregulated at both gene and protein levels in adipocytes treated with samples during differentiation. Further analysis suggested that the anti-adipogenic effect of the compounds might be a result of AMPK activation and the subsequent suppression of MAPK phosphorylation. Overall, the present study suggested that sesquiterpenoids, reynosin, and santamarine were two potential bioactive compounds with anti-adipogenic properties. Further research is needed to explore other bioactive agents within A. scoparia and elucidate the in vivo action mechanisms of reynosin and santamarine.

Anti-adipogenic action of a novel oxazole derivative through activation of AMPK pathway

Obesity is a chronic disorder with multifactorial etiology, including genetic, medical, dietary and other environmental factors. Both natural and synthetic heterocyclic compounds, especially oxazoles, represent an interesting group of compounds and have gained much attention due to their remarkable biological activities. Therefore, a library of 3,3-DMAH (3,3-dimethylallylhalfordinol) inspired N-alkylated oxazole bromide salts with varied substitutions were prepared and screened using the 3T3-L1 model of adipogenesis and HFD-induced obesity model in Syrian golden hamsters. Several compounds in the synthesized series displayed remarkable anti-adipogenic potential on the differentiation of 3T3-L1 preadipocytes. Compound 19e, displayed the most potent activity of all and selected for further studies. Compound 19e inhibited mitotic clonal expansion of 3T3-L1 cells and enhanced the mitochondrial oxygen consumption rate of the cells during early phase of differentiation via AMPK activation. 19e also improved the dyslipidaemia in high calorie diet fed Syrian Golden Hamsters. Therefore, compound 19e can serve as a potential lead against adipogenesis and dyslipidaemia models and could be further investigated to affirm its significance as a drug candidate.

Sex hormone-binding globulin improves lipid metabolism and reduces inflammation in subcutaneous adipose tissue of metabolic syndrome-affected horses

Equine metabolic syndrome (EMS) is a steadily growing endocrine disorder representing a real challenge in veterinary practice. As a multifactorial condition, EMS is characterized by three main metabolic abnormalities including insulin resistance, increased adiposity or obesity and hoof laminitis. Adipose tissue dysfunction is recognized as a core pathophysiological determinant of EMS, as it strongly participates to lipotoxicity and systemic metaflammation, both of which have been closely linked to the development of generalized insulin resistance. Besides, sex hormone binding globulin (SHBG) is an important sex steroids transporters that has been recently proposed as an important metabolic mediator. Therefore, the aim of this study was to verify whether SHBG treatment may ameliorate subcutaneous adipose tissue metabolic failure under EMS condition in terms of lipidome homeostasis, lipid metabolism programs, insulin signalling and local inflammation. Subcutaneous adipose tissue (SAT) biopsies were collected post-mortem from healthy (n = 3) and EMS (n = 3) slaughtered horses. SHBG protein has been applied to SAT samples from EMS horses for 24 h at a final concentration of 50 nM, while control groups (healthy and untreated EMS) were cultured in the presence of SHBG-vehicle only. Tissues from all groups were afterwards secured for downstream analysis of gene expression using RT-qPCR, protein levels by Western blot and ELISA assay and lipidomics through GC-MS technique. Obtained results showcased that SHBG intervention efficiently normalized the altered fatty acids (FAs) profiles by lowering the accumulation of saturated and trans FAs, as well as the pro-inflammatory arachidonic and linoleic acids. Moreover, SHBG showed promising value for the regulation of adipocyte lipolysis and engorgement by lowering the levels of perilipin-1. SHBG exerted moderated effect toward SCD1 and FASN enzymes expression, but increased the LPL abundance. Interestingly, SHBG exhibited a negative regulatory effect on pro-adipogenic stimulators and induced higher expression of KLF3, IRF3 and β-catenin, known as strong adipogenesis repressors. Finally, SHBG protein showed remarkable ability in restoring the insulin signal transduction, IR/IRS/Pi3K/AKT phosphorylation events and GLUT4 transporter abundance, and further attenuate pro-inflammatory response by lowering IL-6 tissue levels and targeting the PDIA3/ERK axis. Overall, the obtained data clearly demonstrate the benefice of SHBG treatment in the regulation of adipose tissue metabolism in the course of EMS and provide new insights for the development of molecular therapies with potential translational application to human metabolic disorders.

Adipose tissue homeostasis orchestrates the oxidative, energetic, metabolic and endocrine disruption induced by binge drinking in adolescent rats

Binge drinking (BD) is the most common alcohol consumption model for adolescents, and has recently been related to the generation of high oxidation and insulin resistance (IR). White adipose tissue (WAT) is a target organ for insulin action that regulates whole-body metabolism by secreting adipokines. The present study aimed to analyse the oxidative, inflammatory, energetic and endocrine profile in the WAT of BD-exposed adolescent rats, to obtain an integrative view of insulin secretion and WAT in IR progression. Two groups of male adolescent rats were used: control (n = 8) and BD (n = 8). An intermittent i.p. BD model (20% v/v) was used during 3 consecutive weeks. BD exposure led to a pancreatic oxidative imbalance, which was joint to high insulin secretion by augmenting deacetylase sirtuin-1 (SIRT-1) pancreatic expression and serum adipsin levels. However, BD rats had hyperglycaemia and high homeostasis model assessment of insulin resistance value (HOMA-IR). BD exposure in WAT increased lipid oxidation, as well as decreased insulin receptor substrate 1 (IRS-1) and AKT expression, sterol regulatory element-binding protein 1 (SREBP1), forkhead box O3A (FOXO3a) and peroxisome proliferator-activated receptor γ (PPARγ), and adipocyte size. BD also affected the expression of proteins related to energy balance, such as SIRT-1 and AMP activated protein kinase (AMPK), affecting the adipokine secretion profile (increasing resistin/adiponectin ratio). BD altered the entire serum lipid profile, increasing the concentration of free fatty acids. In conclusion, BD led to an oxidative imbalance and IR process in WAT, which modified the energy balance in this tissue, decreasing the WAT lipogenic/lipolytic ratio, affecting adipokine secretion and the systemic lipid profile, and contributing to the progression of IR. Therefore, WAT is key in the generation of metabolic and endocrine disruption after BD exposure during adolescence in rats. KEY POINTS: Adolescent rat binge drinking (BD) exposure leads to hepatic and systemic oxidative stress (OS) via reactive oxygen species generation, causing hepatic insulin resistance (IR) and altered energy metabolism. In the present study, BD exposure in adolescent rats induces OS in the pancreas, with increased insulin secretion despite hyperglycaemia, indicating a role for IR in white adipose tissue (WAT) homeostasis. In WAT, BD produces IR and an oxidative and energetic imbalance, triggering an intense lipolysis where the serum lipid profile is altered and free fatty acids are increased, consistent with liver lipid accumulation and steatosis. BD exposure heightens inflammation in WAT, elevating pro-inflammatory and reducing anti-inflammatory adipokines, favouring cardiovascular damage. This research provides a comprehensive view of how adolescent BD in rats impacts liver, WAT and pancreas homeostasis, posing a risk for future cardiometabolic complications in adulthood.

Exploring the pharmacological versatility of ficus carica: Modulating classical immunometabolism and beyond

The burden of metabolic disorders is alarmingly increasing globally. On the other hand, sustainability is the key project of the 21st century. Natural products offer a coherent option for the complementary management of both these challenges. Ficus carica (FC), commonly known as the fig fruit, has an experimentally proven potency for the modulation of cell cycle, immunity, inflammation, metabolism, and oxidative stress. Here, we review the potential of FC-derived products (FCDP) in slowing down the progression of cancers, acute/chronic inflammation-related conditions, infections, metabolic disorders, toxicities, neurological and neuromuscular diseases, gastrointestinal disorders, vascular diseases, and skin-stressing conditions, as well as, in boosting normal healthy functions of the endocrine, immune, metabolic, and nervous systems. It reveals a variety of cellular and molecular targets for FCDP: cytokines (TNF-α, IL-1β, IL-6, IL-10, IL-12, IL-18, IFN-γ), chemokines (CCL2), other inflammatory mediators (CRP, PGE2), immune receptors (TLR-2, TLR-4, FcεRI), oxidative stress-related markers (SOD, GSH, MDA, GPx, catalase, ROS, NO, protein carbonyls), kinases (MAPKs, hexokinase, G6Pase, FBPase, PEPCK, Akt, AMPK, GSK3, CDKs), other enzymes (COX-2, iNOS, MMPs, caspases), growth factors/receptors (VEGF, EGFR), hormones (DHEAS, prolactin, GnRH, FSH, LH, estradiol, DHT, insulin), cell death-related markers (Bcl-2, Bax, Bak, FasL, gasdermins, cytochrome C), glucose transporter protein (Glut4), and transcription factors (NF-κB, HNF-4α, Foxo, PGC-1α, PPAR-γ, C/EBP-α, CREB, NFATC1, STAT3). FCDP cause both activation and inhibition of AMPK, MAPK, and NF-κB signaling to confer condition-specific advantages. Such a broad-range activity might be attributed to different mechanisms of action of FCDP in modulating functions within the classical immunometabolic system, but also beyond.