Phenolic Compounds Inhibit 3T3-L1 Adipogenesis Depending on the Stage of Differentiation and Their Binding Affinity to PPARγ

Preliminary hazard assessment of a new nature-inspired antifouling (NIAF) agent

A recently synthesized aminated 3,4-dioxygenated xanthone (Xantifoul2) was found to have promising antifouling (AF) effects against the settlement of the macrofouler Mytilus galloprovincialis larvae. Preliminary assessment indicated that Xantifoul2 has reduced ecotoxicological impacts: e.g., being non-toxic to the marine crustacea Artemia salina (<10 % mortality at 50 μM) and showing low bioconcentration factor in marine organisms. In order to meet the EU Biocidal Product Regulation, a preliminary hazard assessment of this new nature-inspired antifouling (NIAF) agent was conducted in this work. Xantifoul2 did not affect the swimming ability of the planktonic crustacean Daphnia magna, the growth of the diatom Phaeodactylum tricornutum, and the cellular respiration of luminescent Gram-negative bacteria Vibrio fischeri, supporting the low toxicity towards several non-target marine species. Regarding human cytotoxicity, Xantifoul2 did not affect the cell viability of retinal human cells (hTERT-RPE-1) and lipidomic studies revealed depletion of lipids involved in cell death, membrane modeling, lipid storage, and oxidative stress only at a high concentration (10 μM). Accelerated degradation studies in water were conducted under simulated sunlight to allow the understanding of putative transformation products (TPs) that could be generated in the aquatic ecosystems. Both Xantifoul2 and photolytic-treated Xantifoul2 in the aqueous matrix were therefore evaluated on several nuclear receptors (NRs). The results of this preliminary hazard assessment of Xantifoul2, combined with the high degradation rates in water, provide strong evidence of the safety of this AF agent under the evaluated conditions, and provide the support for future validation studies before this compound can be introduced in the market.

In Vitro Screening and Lipid-Lowering Effect of Prickly Pear (Opuntia Ficus-Indica L. Mill.) Fruit Extracts in 3T3-L1 Pre-Adipocytes and Mature Adipocytes

Opuntia ficus-indica fruits have been widely used due to their nutritional composition and beneficial effects on health, particularly against chronic diseases such as diabetes, obesity, cardiovascular diseases and cancer, among others. In recent years, prickly pear peel and pulp extracts have been characterised, and a high number of bioactive compounds have been identified. This study aimed to analyse the triglyceride-lowering effect of prickly pear peel and pulp extracts obtained from fruits of three varieties (Pelota, Sanguinos, and Colorada) in 3T3-L1 maturing and mature adipocytes. At a concentration of 50 µg/mL, peel extracts from Colorada reduced triglyceride accumulation in pre-adipocytes and mature adipocytes. Additionally, at 25 µg/mL, Pelota peel extract decreased triglyceride content in mature adipocytes. Moreover, maturing pre-adipocytes treated with 50 and 25 µg/mL of Sanguinos pulp extract showed a reduction of triglyceride accumulation. In addition, the lipid-lowering effect of the main individual betalain and phenolic compounds standards were assayed. Piscidic acid and isorhamnetin glycoside (IG2), found in Colorada peel extract, were identified as the bioactive compounds that could contribute more notably to the triglyceride-lowering effect of the extract. Thus, the betalain and phenolic-rich extracts from Opuntia ficus indica fruits may serve as an effective tool in obesity management.

Rational design of thiazolidine-4-one-gallic acid hybrid derivatives as selective partial PPARγ modulators: an in-silico approach for type 2 diabetes treatment

Type 2 diabetes mellitus is a bipolar metabolic disorder characterized by abnormalities in insulin production from β-cells and insulin resistance. Thiazolidinediones are potent anti-diabetic agents that act through the modulation of the peroxisome proliferator-activated receptor γ (PPARγ), a nuclear receptor. However, their full agonistic activity leads to severe side effects by stabilizing Helix12 through strong hydrogen bonding with the TYR473 residue. Partial and selective PPARγ modulators (GW0072, GQ16, VSP-51, MRL-20, MBX-213, INT131) have demonstrated superior results compared to full agonists without causing adverse effects, as reported in existing data. To address this uncertainty and advance therapeutic options, we identified and designed a novel class of compounds (A1-A23) based on a hybrid structure combining phenolic and Thiazolidine-4-one's moieties. Our rational drug design strategy incorporated structural-activity relationship principle, and validated the docking studies through calculated the root mean square deviation. Additionally, we conducted molecular docking, binding energy, molecular dynamics simulations, and post-molecular dynamics calculations to evaluate the dynamics behavior between the ligands and protein. The selected ligands demonstrated highly favorable docking scores and binding energies, comparable to the co-crystal (rosiglitazone) such as A12 (-13.9 kcal/mol and -86.2 kcal/mol), A1 (-11.1 kcal/mol and -79.5 kcal/mol), A13 (-11.3 kcal/mol and -91.4 kcal/mol), and the co-crystal itself (-9.8 kcal/mol and -76 kcal/mol), respectively. Finally, the MD revealed that, the selected ligands were equally contributed for stabilization of Helix12 and β-sheets. It was concluded, the designed ligands (A12, A1, and A13) exhibited weaker hydrogen-bond interactions with specific residue TYR473 which partially modulated the PPARγ protein.Communicated by Ramaswamy H. Sarma.

Dietary Phenolic Compounds Exert Some of Their Health-Promoting Bioactivities by Targeting Liver X Receptor (LXR) and Retinoid X Receptor (RXR)

Consuming foods of vegetable origin has been shown to exert multiple health-related effects, many of them attributed to their phenolic compounds. These molecules are known for being bioactive across multiple cells and organs, with documented changes in gene expression being commonly reported. Nuclear receptors are signal transducers capable of regulating gene expression in response to endogenous and/or exogenous ligands. Liver X receptor (LXR) and retinoid X receptor (RXR) are two important nuclear receptors that can be acted on by phenolic compounds, thereby modifying gene expression and potentially exerting numerous subsequent bioactivities. The present work summarizes recent evidence of the effects of the phenolic compounds that are exerted by targeting LXR and/or RXR. The data show that, when LXR is being targeted, changes in lipid metabolism are commonly observed, due to its ability to regulate genes relevant to this process. The effects vary widely when RXR is the target since it is involved in processes like cell proliferation, vitamin D metabolism, and multiple others by forming heterodimers with other transcription factors that regulate said processes. The evidence therefore shows that phenolic compounds can exert multiple bioactivities, with a mechanism of action based, at least in part, on their ability to modulate the cell at the molecular level by acting on nuclear receptors. The data point to a promising and novel area of study that links diet and health, although various unknowns justify further experimentation to reveal the precise way in which a given phenolic can interact with a nuclear receptor.

Influence of Polyphenols on Adipose Tissue: Sirtuins as Pivotal Players in the Browning Process

Adipose tissue (AT) can be classified into two different types: (i) white adipose tissue (WAT), which represents the largest amount of total AT, and has the main function of storing fatty acids for energy needs and (ii) brown adipose tissue (BAT), rich in mitochondria and specialized in thermogenesis. Many exogenous stimuli, e.g., cold, exercise or pharmacological/nutraceutical tools, promote the phenotypic change of WAT to a beige phenotype (BeAT), with intermediate characteristics between BAT and WAT; this process is called "browning". The modulation of AT differentiation towards WAT or BAT, and the phenotypic switch to BeAT, seem to be crucial steps to limit weight gain. Polyphenols are emerging as compounds able to induce browning and thermogenesis processes, potentially via activation of sirtuins. SIRT1 (the most investigated sirtuin) activates a factor involved in mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), which, through peroxisome proliferator-activated receptor γ (PPAR-γ) modulation, induces typical genes of BAT and inhibits genes of WAT during the transdifferentiation process in white adipocytes. This review article aims to summarize the current evidence, from pre-clinical studies to clinical trials, on the ability of polyphenols to promote the browning process, with a specific focus on the potential role of sirtuins in the pharmacological/nutraceutical effects of natural compounds.

Juniper Berries Regulate Diabetes and Obesity Markers Through Modulating PPARα, PPARγ, and LXR: In Vitro and In Vivo Effects

The berries of Juniperus communis have been traditionally used for therapeutic purposes. They have been reported to possess various pharmacological effects such as anti-inflammatory, hypoglycemic and hypolipidemic activities. In this study, a methanolic extract of J. communis berries (JB) was evaluated for its effects on peroxisome proliferator-activated receptors alpha and gamma (PPARα and PPARγ), liver X receptor (LXR), glucose uptake and lipid accumulation using various cellular systems. At a concentration of 25 μg/mL, JB caused 3.77-fold activation of PPARα, 10.90-fold activation of PPARγ, and 4.43-fold activation of LXR in hepatic cells. JB inhibited (11%) the adipogenic effect induced by rosiglitazone in adipocytes and increased glucose uptake (90%) in muscle cells. In high-fat diet (HFD) fed mice, JB at a dose of 25 mg/kg body weight exhibited a 21% decrease in body weight. Fasting glucose levels in mice treated with 12.5 mg/kg of JB were significantly decreased (39%) indicating its efficacy in regulating hyperglycemia and obesity induced by HFD thus ameliorating the symptoms of type 2 diabetes. A series of energy metabolic genes, including Sirt1 (2.00-fold) and RAF1 (2.04-fold), were upregulated by JB, while rosiglitazone regulated the hepatic PPARγ only. Phytochemical analysis of JB indicated presence of a number of flavonoids and biflavonoids which seem to be responsible for the observed activity. It was concluded that JB acted as a multiple agonist of PPARα, PPARγ and LXR without the undesired effect of adipogenesis and exhibited the property of enhancing glucose uptake. The regulation of PPARα, PPARγ and LXR seems to be through Sirt1 and RAF1. In vivo results confirmed the antidiabetic and antiobesity potential of JB and indicated its utility in metabolic disorder and type 2 diabetes.

In Silico Identification of Peptides with PPARγ Antagonism in Protein Hydrolysate from Rice (Oryza sativa)

At least half the population in industrialized countries suffers from obesity due to excessive accumulation of adipose tissue. Recently, rice (Oryza sativa) proteins have been considered valuable sources of bioactive peptides with antiadipogenic potential. In this study, the digestibility and bioaccessibility in vitro of a novel protein concentrate (NPC) from rice were determined through INFOGEST protocols. Furthermore, the presence of prolamin and glutelin was evaluated via SDS-PAGE, and their potential digestibility and the bioactivity of ligands against peroxisome proliferator-activated receptor gamma (PPARγ) were explored by BIOPEP UWM and HPEPDOCK. For the top candidates, molecular simulations were conducted using Autodock Vina to evaluate their binding affinity against the antiadipogenic region of PPARγ and their pharmacokinetics and drug-likeness using SwissADME. Simulating gastrointestinal digestion showed a recovery of 43.07% and 35.92% bioaccessibility. The protein banding patterns showed the presence of prolamin (57 kDa) and glutelin (12 kDa) as the predominant proteins in the NPC. The in silico hydrolysis predicts the presence of three and two peptide ligands in glutelin and prolamin fraction, respectively, with high affinity for PPARγ (≤160). Finally, the docking studies suggest that the prolamin-derived peptides QSPVF and QPY (−6.38 & −5.61 kcal/mol, respectively) have expected affinity and pharmacokinetic properties to act as potential PPARγ antagonists. Hence, according to our results, bioactive peptides resulting from NPC rice consumption might have an antiadipogenic effect via PPARγ interactions, but further experimentation and validation in suitable biological model systems are necessary to gain more insight and to provide evidence to support our in silico findings.

Luteolin protects against adipogenic and lipogenic potency induced by human relevant mixtures of persistent organic pollutants (POPs) in the 3T3-L1 model

Human exposure to persistent organic pollutants (POPs) may contribute to obesogenic effects. We have previously shown that POP mixtures modelled on blood levels relevant to the Scandinavian population induces adipogenic effects in the mouse 3T3-L1 cell line. Luteolin is a flavone that has shown anti-lipogenic and anti-adipogenic effects on adipogenesis in in vitro models. In this study, luteolin has been applied to inhibit adipocyte formation and intracellular lipid content increase induced by a human relevant mixture of POPs. 3T3-L1 cells were exposed to a POP mixture consisting of 29 chemicals, including amongst others polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), perfluoroalkylated acids (PFAAs), and polybrominated diphenyl ethers (PBDEs). Rosiglitazone was applied as a positive lipogenic control. Luteolin was tested between 0.5 and 10 μM. High content analysis was used to assess changes in adipocyte formation and intracellular lipid content in the 3T3-L1 cell line. Luteolin significantly reduced POP-induced adipocyte formation at 2, 5 and 10 μM, and lipid accumulation at 10 μM. Interestingly, luteolin did not affect rosiglitazone induced adipo- and lipogenic effects, suggesting differences in mechanisms of action. In conclusion, this in vitro study shows that dietary polyphenols such as luteolin may protect against POP induced adipo- and lipogenic effects.

A Novel Mix of Polyphenols and Micronutrients Reduces Adipogenesis and Promotes White Adipose Tissue Browning via UCP1 Expression and AMPK Activation

Background: Obesity is a pandemic disease characterized by excessive severe body comorbidities. Reduction in fat accumulation represents a mechanism of prevention, and the replacement of white adipose tissue (WAT) with brown adipose tissue (BAT) has been proposed as one promising strategy against obesity. In the present study, we sought to investigate the ability of a natural mixture of polyphenols and micronutrients (A5⁺) to counteract white adipogenesis by promoting WAT browning. Methods: For this study, we employed a murine 3T3-L1 fibroblast cell line treated with A5⁺, or DMSO as control, during the differentiation in mature adipocytes for 10 days. Cell cycle analysis was performed using propidium iodide staining and cytofluorimetric analysis. Intracellular lipid contents were detected by Oil Red O staining. Inflammation Array, along with qRT-PCR and Western Blot analyses, served to measure the expression of the analyzed markers, such as pro-inflammatory cytokines. Results: A5⁺ administration significantly reduced lipids' accumulation in adipocytes when compared to control cells (p < 0.005). Similarly, A5⁺ inhibited cellular proliferation during the mitotic clonal expansion (MCE), the most relevant stage in adipocytes differentiation (p < 0.0001). We also found that A5⁺ significantly reduced the release of pro-inflammatory cytokines, such as IL-6 and Leptin (p < 0.005), and promoted fat browning and fatty acid oxidation through increasing expression levels of genes related to BAT, such as UCP1 (p < 0.05). This thermogenic process is mediated via AMPK-ATGL pathway activation. Conclusion: Overall, these results demonstrated that the synergistic effect of compounds contained in A5⁺ may be able to counteract adipogenesis and then obesity by inducing fat browning.

Potential of enhancing anti-obesogenic agriceuticals by applying sustainable fertilizers during plant cultivation

Overweight and obesity are two of the world's biggest health problems. They are associated with excessive fat accumulation resulting from an imbalance between energy consumed and energy expended. Conventional therapies for obesity commonly include synthetic drugs and surgical procedures that can lead to serious side effects. Therefore, developing effective, safe, and readily available new treatments to prevent and treat obesity is highly relevant. Many plant extracts have shown anti-obesogenic potential. These plant extracts are composed of different agriceuticals such as fibers, phenolic acids, flavonoids, anthocyanins, alkaloids, lignans, and proteins that can manage obesity by suppressing appetite, inhibiting digestive enzymes, reducing adipogenesis and lipogenesis, promoting lipolysis and thermogenesis, modulating gut microbiota and suppressing obesity-induced inflammation. These anti-obesogenic agriceuticals can be enhanced in plants during their cultivation by applying sustainable fertilization strategies, improving their capacity to fight the obesity pandemic. Biofertilization and nanofertilization are considered efficient, eco-friendly, and cost-effective strategies to enhance plant growth and development and increase the content of nutrients and bioactive compounds, representing an alternative to overproducing the anti-obesogenic agriceuticals of interest. However, further research is required to study the impact of anti-obesogenic plant species grown using these agricultural practices. This review presents the current scenario of overweight and obesity; recent research work describing different plant species with significant effects against obesity; and several reports exhibiting the potential of the biofertilization and nanofertilization practices to enhance the concentrations of bioactive molecules of anti-obesogenic plant species.

Antifouling Marine Coatings with a Potentially Safer and Sustainable Synthetic Polyphenolic Derivative

The development of harmless substances to replace biocide-based coatings used to prevent or manage marine biofouling and its unwanted consequences is urgent. The formation of biofilms on submerged marine surfaces is one of the first steps in the marine biofouling process, which facilitates the further settlement of macrofoulers. Anti-biofilm properties of a synthetic polyphenolic compound, with previously described anti-settlement activity against macrofoulers, were explored in this work. In solution this new compound was able to prevent biofilm formation and reduce a pre-formed biofilm produced by the marine bacterium, Pseudoalteromonas tunicata. Then, this compound was applied to a marine coating and the formation of P. tunicata biofilms was assessed under hydrodynamic conditions to mimic the marine environment. For this purpose, polyurethane (PU)-based coating formulations containing 1 and 2 wt.% of the compound were prepared based on a prior developed methodology. The most effective formulation in reducing the biofilm cell number, biovolume, and thickness was the PU-based coating containing an aziridine-based crosslinker and 2 wt.% of the compound. To assess the marine ecotoxicity impact of this compound, its potential to disrupt endocrine processes was evaluated through the modulation of two nuclear receptors (NRs), peroxisome proliferator-activated receptor γ (PPARγ), and pregnane X receptor (PXR). Transcriptional activation of the selected NRs upon exposure to the polyphenolic compound (10 µM) was not observed, thus highlighting the eco-friendliness towards the addressed NRs of this new dual-acting anti-macro- and anti-microfouling agent towards the addressed NRs.

Analysis of Major Polyphenolic Compounds of Cydonia oblonga Miller (Quince) Fruit Extract by UPLC-MS/MS and Its Effect on Adipogenesis in 3T3-L1 Cells

Cydonia oblonga miller (quince) plant serves as a potential folk medicine for treating hypertension and cardiovascular diseases in China. However, to the best of our knowledge, no study has been conducted on the polyphenolic profile and anti-adipogenic effect of quince fruit grown in China. In the current study, we aimed to investigate the quince fruit extract’s major phenolic compounds, evaluate their antioxidant activity, and examine their effect on adipogenesis in 3T3-L1 cells. A rapid and sensitive analytical method was established for the simultaneous determination of major polyphenolic compounds by using ultra-pressure liquid chromatography coupled with a triple quadrupole mass spectrometer (UPLC-MS/MS). Among the 10 compounds, the cryptochlorgenic acid was noticed as the most abundant compound of both purified (242.44 ± 0.73 µg/mg dw) and unpurified extract (3.37 ± 0.01 µg/mg dw) followed by quercetin 3-rutinoside and chlorogenic acid. Alternatively, both extracts possessed a high quantity of phenolic acids (purified extract = 483.10 ± 5.16 µg/mg dw and unpurified extract = 7.89 ± 0.02 µg/mg dw). The purified extract exhibited a strong antioxidant capacity (DPPH: EC50 = 3.316 µg/mL, ABTS: EC50 = 36.38 µg/mL) as compared to the unpurified extract. Additionally, our results also showed that the extract at 100 µg/mL significantly suppressed the preadipocyte differentiation and decreased the lipid droplets up to 69% in mature adipocytes. The present study highlights an accurate and fast detection method for quince fruit extract polyphenolic compounds with its antioxidant and antiadipogenic effects. The study also provides the necessary information for the rational development and utilization of quince fruit extract as a source of phytochemicals.

Derhamnosylmaysin Inhibits Adipogenesis via Inhibiting Expression of PPARγ and C/EBPα in 3T3-L1 Cells

We investigated the effects of derhamnosylmaysin (DM) on adipogenesis and lipid accumulation in 3T3-L1 adipocytes. Our data showed that DM inhibited lipid accumulation and adipocyte differentiation in 3T3-L1 cells. Treatment of 3T3-L1 adipocytes with DM decreased the expression of major transcription factors, such as sterol regulatory element-binding protein-1c (SREBP-1c), the CCAAT-enhancer-binding protein (CEBP) family, and peroxisome proliferator-activated receptor gamma (PPARγ), in the regulation of adipocyte differentiation. Moreover, the expression of their downstream target genes related to adipogenesis and lipogenesis, including adipocyte fatty acid-binding protein (aP2), lipoprotein lipase (LPL), stearyl-CoA-desaturase-1 (SCD-1), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS), was also decreased by treatment with DM during adipogenesis. Additionally, DM attenuated insulin-stimulated phosphorylation of Akt. These results first demonstrated that DM inhibited adipogenesis and lipogenesis through downregulation of the key adipogenic transcription factors SREBP-1c, the CEBP family, and PPARγ and inactivation of the major adipogenesis signaling factor Akt, which is intermediated in insulin. These studies demonstrated that DM is a new bioactive compound for antiadipogenic reagents for controlling overweight and obesity.

Ameliorative Effects of Lactobacillus plantarum HAC01 Lysate on 3T3-L1 Adipocyte Differentiation via AMPK Activation and MAPK Inhibition

Lactobacillus plantarum HAC01 has been shown to effectively treat metabolic diseases. However, the precise pharmacological effects and molecular mechanisms of L. plantarum HAC01 remain unclear. In this study, we investigate the anti-adipogenic effects of L. plantarum HAC01 lysate and its associated mechanism of action. To induce lipid accumulation, 3T3-L1 cells were incubated in differentiation media with or without L. plantarum HAC01 lysate. Our results show that L. plantarum HAC01 lysate treatment not only reduced lipid accumulation during the differentiation of 3T3-L1 cells, but also decreased the expression of adipogenic and lipogenic genes involved in lipid metabolism in a dose-dependent manner. Additionally, L. plantarum HAC01 lysate inhibited CCAAT/enhancer-binding protein (C/EBP) beta within 4 h of differentiation induction and inhibited peroxisome proliferator-activated receptor gamma, C/EBP alpha, and sterol regulatory element-binding proteins within 2 d. Moreover, treatment with L. plantarum HAC01 lysate increased the phosphorylation of adenosine monophosphate-activated protein kinase, an important regulator of energy metabolism, and decreased the phosphorylation of mitogen-activated protein kinase. These results indicate that L. plantarum HAC01 lysate may have anti-adipogenic effects and support its potential as a useful agent for the treatment of obesity.

Role of Bioactive Compounds in Obesity: Metabolic Mechanism Focused on Inflammation

Obesity is a disease characterized by an inflammatory process in the adipose tissue due to diverse infiltrated immune cells, an increased secretion of proinflammatory molecules, and a decreased secretion of anti-inflammatory molecules. On the other hand, obesity increases the risk of several diseases, such as cardiovascular diseases, diabetes, and cancer. Their treatment is based on nutritional and pharmacological strategies. However, natural products are currently implemented as complementary and alternative medicine (CAM). Polyphenols and fiber are naturally compounds with potential action to reduce inflammation through several pathways and play an important role in the prevention and treatment of obesity, as well as in other non-communicable diseases. Hence, this review focuses on the recent evidence of the molecular mechanisms of polyphenols and dietary fiber, from Scopus, Science Direct, and PubMed, among others, by using key words and based on recent in vitro and in vivo studies.

Multiple Bioactivities of Manihot esculenta Leaves: UV Filter, Anti-Oxidation, Anti-Melanogenesis, Collagen Synthesis Enhancement, and Anti-Adipogenesis

The cassava root is an important global agro-industrial crop that yields cassava leaf as a left-over co-product of interest for further development as a sustainable resource of health and cosmeceutical active compounds. This work aimed to investigate the cosmeceutical potential and chemical composition of an ethanolic cassava leaf extract (BM). rutin, apigenin, and kaempferol were found to be major constituents via HPLC-DAD UV analysis. Interestingly, the multiple beneficial bioactivities of BM for cosmeceutical applications were manifested in a dose-dependent manner, including anti-oxidation in a 2,2-diphenyl-1-picrylhydrazyl assay, anti-melanogenesis in B16 melanoma cells, collagen synthesis enhancement in human fibroblasts, and anti-adipogenesis in 3T3-L1 adipocytes. Furthermore, the potential of the collagen synthesis enhancement of BM and rutin was significant when compared to ascorbic acid. Additionally, a UV filter property comparable to BEMT with characteristics of board spectral absorption and constant high absorptivity throughout all UV wavelength ranges was exhibited by UV-visible spectrophotometric analysis. In conclusion, the cassava leaf was found to be a potential natural cosmeceutical active agent with multiple cosmeceutical-related bioactivities with respect to a substantial composition of bioactive flavonols. These obtained data will support and encourage the further study and development of cassava leaves as potential economic and sustainable sources of bioactive agents for health and cosmeceutical applications.

Vaccinium virgatum Aiton Leaves Extract Suppressed Lipid Accumulation and Uric Acid Production in 3T3-L1 Adipocytes

Blueberry (Vaccinium virgatum Aiton; Kinisato 35 Gou) leaves have recently attracted increasing attention as a useful material for the prevention of lifestyle diseases. Here, we examined the effects of the hot water extract of blueberry leaves (BLEx) on lipogenesis and uric acid production in 3T3-L1 adipocytes. The results showed that BLEx suppressed lipid accumulation and the mRNA expression of differentiation markers in 3T3-L1 adipocytes. A fractionation study showed that the highly polymerized proanthocyanidin-rich fraction was responsible for this effect. Upon maturation to adipocytes, 3T3-L1 cells produced uric acid and tumor necrosis factor-α, and hypoxia stimulated the production of uric acid and xanthine oxidoreductase activity. BLEx suppressed the production of uric acid under these conditions. Although BLEx inhibited the enzymatic activity of xanthine oxidase, this activity was observed in several fractions containing catechin, epicatechin, chlorogenic acid, rutin, and low molecular weight proanthocyanidins. Taken together, these results indicate that BLEx contains various compounds with the ability to suppress lipid accumulation and uric acid production in adipocytes.

A mix of chlorogenic and caffeic acid reduces C/EBPß and PPAR-γ1 levels and counteracts lipid accumulation in macrophages

PURPOSE

Chlorogenic acid (CGA) and caffeic acid (CA) are bioactive compounds in whole grains, berries, apples, some citrus fruits and coffee, which are hypothesized to promote health-beneficial effects on the cardiovascular system. This study aimed to evaluate the capacity of CGA and CA to reduce lipid accumulation in macrophages, recognized as a critical stage in the progression of atherosclerosis. Furtherly, the modulation of CCAAT/enhancer-binding protein β (C/EBPβ) and peroxisome proliferator-activated receptor- γ1 (PPAR-γ1), as transcription factors involved in lipid metabolism, was evaluated.

METHODS

THP-1-derived macrophages were treated for 24 h with 0.03, 0.3, 3 and 30 μM of CGA and CA, tested alone or in combination, and a solution of oleic/palmitic acid (500 μM, 2:1 ratio). Lipid storage was assessed spectrophotometrically through fluorescent staining of cells with Nile red. C/EBPβ and PPAR-γ1 mRNA and protein levels were evaluated by RT-PCR and enzyme-linked immunosorbent assay, respectively.

RESULTS

The mix of CGA + CA (1:1 ratio) reduced lipid accumulation at all concentrations tested, except for the highest one. The greatest effect ( - 65%; p < 0.01) was observed at the concentration of 0.3 μM for each compound. The same concentration significantly (p < 0.01) downregulated C/EBPβ and PPAR-γ1 gene expression and reduced their protein levels at 2 h and 24 h, respectively.

CONCLUSION

The results indicate that the capacity of CGA + CA mix to reduce lipid storage in macrophages is mediated by a reduction in the expression of transcription factors C/EBPβ and PPAR-γ1.

β-RA Targets Mitochondrial Metabolism and Adipogenesis, Leading to Therapeutic Benefits against CoQ Deficiency and Age-Related Overweight

Primary mitochondrial diseases are caused by mutations in mitochondrial or nuclear genes, leading to the abnormal function of specific mitochondrial pathways. Mitochondrial dysfunction is also a secondary event in more common pathophysiological conditions, such as obesity and metabolic syndrome. In both cases, the improvement and management of mitochondrial homeostasis remain challenging. Here, we show that beta-resorcylic acid (β-RA), which is a natural phenolic compound, competed in vivo with 4-hydroxybenzoic acid, which is the natural precursor of coenzyme Q biosynthesis. This led to a decrease in demethoxyubiquinone, which is an intermediate metabolite of CoQ biosynthesis that is abnormally accumulated in Coq9^R239X mice. As a consequence, β-RA rescued the phenotype of Coq9^R239X mice, which is a model of primary mitochondrial encephalopathy. Moreover, we observed that long-term treatment with β-RA also reduced the size and content of the white adipose tissue (WAT) that is normally accumulated during aging in wild-type mice, leading to the prevention of hepatic steatosis and an increase in survival at the elderly stage of life. The reduction in WAT content was due to a decrease in adipogenesis, an adaptation of the mitochondrial proteome in the kidneys, and stimulation of glycolysis and acetyl-CoA metabolism. Therefore, our results demonstrate that β-RA acted through different cellular mechanisms, with effects on mitochondrial metabolism; as such, it may be used for the treatment of primary coenzyme Q deficiency, overweight, and hepatic steatosis.

Myricetin 3-O-β-D-Galactopyranoside Exhibits Potential Anti-Osteoporotic Properties in Human Bone Marrow-Derived Mesenchymal Stromal Cells via Stimulation of Osteoblastogenesis and Suppression of Adipogenesis

Natural bioactive substances are promising lead compounds with beneficial effects on various health problems including osteoporosis. In this context, the goal of this study was to investigate the effect of myricetin 3-O-β-D-galactopyranoside (M3G), a glycoside of a known bioactive phytochemical myricetin, on bone formation via osteogenic differentiation of human bone marrow-derived mesenchymal stromal cells (hBM-MSCs). The hBM-MSCs were induced to differentiate into osteoblasts and adipocytes in the presence or absence of M3G and the differentiation markers were analyzed. Osteoblastogenesis-induced cells treated with M3G exhibited stimulated differentiation markers: cell proliferation, alkaline phosphatase (ALP) activity, and extracellular mineralization. In terms of intracellular signaling behind the stimulatory effect of M3G, the expression of RUNX2 and osteopontin transcription factors were upregulated. It has been shown that M3G treatment increased the activation of Wnt and BMP as a suggested mechanism of action for its effect. On the other hand, M3G treatment during adipogenesis-inducement of hBM-MSCs hindered the adipogenic differentiation shown as decreased lipid accumulation and expression of PPARγ, SREBP1c, and C/EBPα, adipogenic transcription factors. In conclusion, M3G treatment stimulated osteoblast differentiation and inhibited adipocyte differentiation in induced hBM-MSCs. Osteoblast formation was stimulated via Wnt/BMP and adipogenesis was inhibited via the PPARγ pathway. This study provided necessary data for further studies to utilize the therapeutic potential of M3G against osteoporosis via regulation of bone marrow stromal cell differentiation.

Chamomile as a potential remedy for obesity and metabolic syndrome

Obesity is an increasing health concern related to many metabolic disorders, including metabolic syndrome, diabetes type 2 and cardiovascular diseases. Many studies suggest that herbal products can be useful dietary supplements for weight management due to the presence of numerous biologically active compounds, including antioxidant polyphenols that can counteract obesity-related oxidative stress. In this review we focus on Matricaria chamomilla, commonly known as chamomile, and one of the most popular medicinal plants in the world. Thanks to a high content of phenolic compounds and essential oils, preparations from chamomile flowers demonstrate a number of pharmacological effects, including antioxidant, anti-inflammatory, antimicrobial and sedative actions as well as improving gastrointestinal function. Several recent studies have shown certain positive effects of chamomile preparations in the prevention of obesity and complications of diabetes. These effects were associated with modulation of signaling pathways involving the AMP-activated protein kinase, NF-κB, Nrf2 and PPARγ transcription factors. However, the potential of chamomile in the management of obesity seems to be underestimated. This review summarizes current data on the use of chamomile and its individual components (apigenin, luteolin, essential oils) to treat obesity and related metabolic disorders in cell and animal models and in human studies. Special attention is paid to molecular mechanisms that can be involved in the anti-obesity effects of chamomile preparations. Limitation of chamomile usage is also analyzed.

Protein Concentrates on Tepary Bean (Phaseolus acutifolius Gray) as a Functional Ingredient: In silico Docking of Tepary Bean Lectin to Peroxisome Proliferator-Activated Receptor Gamma

The tepary bean (Phaseolus acutifolius Gray) is a US-Mexico frontier native crop, produces high yields in agriculture, and needs to be reconsidered because of its nutritional and functional properties. This study aimed to determine the technological and nutritional properties of flours and protein concentrates of tepary bean, besides determining an in silico agonist effect of tepary bean lectin to peroxisome proliferator-activated receptor gamma (PPAR-γ). We evaluated the technological properties of raw samples (tepary flour and tepary protein concentrate) and cooked samples (tepary flour and tepary protein concentrate). The flours present a significant difference (p < 0.05) concerning protein concentrates in water absorption and oil absorption capacity. The raw samples' emulsifying capacity was higher than that reported in the literature for other legumes, but not the cooked samples. The samples' foaming capacity had no significant difference in treatments (p > 0.05), and cooked tepary bean protein concentrate presented complete gelation at a lower concentration (2%). Nutritionally, raw samples present a protein percentage of 23.46 ± 0.06 and 71.38 ± 0.44 and cooked samples present a protein percentage of 25.27 ± 0.04 and 62.69 ± 0.14; a chemical score of 72, 86, 82, and 72; in vitro protein digestibility (%) = 48.20 ± 0.31, 49.80 ± 0.80, 61.77 ± 1.70, and 63.61 ± 4.19; and C-PER = 0.86, 1.34, 1.93, and 1.81, respectively. All the samples showed methionine + cysteine as the limiting amino acid. All these nutritional data are very similar to the common bean (Phaseolus vulgaris). SDS-PAGE preserves the lectin fraction in both protein concentrates. The in silico study of tepary lectin (PDB: 6tt9) shows that there were seven peptides that presented values below -120 kcal/mol: PEW, VSVGF, PSQK, TTPW, ATSF, ITY, and TSF, with VSVGF, PSQK, and PEW having the highest affinity for active sites of the PAPRγ receptor (binding energies from -5.32 to -7.04 kcal/mol). These peptides could show antiadipogenic or antidiabetic activity based on the intermolecular bond energies and open an interesting research item.

Expression status and prognostic value of the perilipin family of genes in breast cancer

BACKGROUND

The Perilipin (PLIN) family of genes were previously shown to be involved in the formation and degradation of Lipid Droplets (LDs). In addition, they may play important roles in the development and progression of breast cancer. However, the prognostic value of PLIN family members in breast cancer patients remains unclear.

METHODS

Mutations and copy number alterations of PLIN family genes in breast cancer were examined using the cBioportal for Cancer Genomics. In addition, the expression patterns of PLIN family genes were explored using the UCSC Xena online tool. Finally, the Kaplan-Meier Plotter was used to investigate the prognostic value of PLIN family genes in breast cancer.

RESULTS

The findings revealed a low frequency of genetic alterations and amplification was the most frequent change in the PLIN family genes. Additionally, there was an increase in the expression of Perilipin 3 (PLIN3) in breast cancer tissues compared to normal breast tissues. However, expression of the other genes in the PLIN family was significantly lower in breast cancer tissues compared to normal breast tissues. Moreover, there was an increase in the expression levels of Perilipin 1 (PLIN1), PLIN3, Perilipin 4 (PLIN4) and Perilipin 5 (PLIN5) in the luminal A and luminal B subgroups. On the other hand, the expression of Perilipin 2 (PLIN2) was elevated in the human epidermal growth factor receptor 2 (HER2) positive and basal-like subgroups. Furthermore, Kaplan-Meier Plotter analysis demonstrated that high expression of PLIN1 might predict a longer Overall Survival (OS) in patients with breast cancer while overexpression of PLIN2 indicated poor OS of breast cancer patients.

CONCLUSION

The findings from this study indicated that genes in the PLIN family were aberrantly expressed in breast cancer and may serve as novel therapeutic targets as well as prognostic biomarkers for the disease.

Natural products and analogs as preventive agents for metabolic syndrome via peroxisome proliferator-activated receptors: An overview

Natural products and synthetic analogs have drawn much attention as potential therapeutical drugs to treat metabolic syndrome. We reviewed the underlying mechanisms of 32 natural products and analogs with potential pharmacological effects in vitro, and especially in rodent models and/or patients, that usually act on the PPAR pathway, along with other molecular targets. Recent outstanding total syntheses or semisyntheses of these lead compounds are stated. In general, they can activate the transcriptional activity of PPARα, PPARγ, PPARα/γ, PPARβ/δ, PPARα/δ, PPARγ/δ and panPPAR as weak, partial agonists or selective PPARγ modulators (SPPARγM), which may be useful for managing obesity, type 2 diabetes (T2D), dyslipidemia and non-fatty liver disease (NAFLD). Terpenoids is the largest group of compounds that act as potential modulators on PPARs and are comprised from small lipophilic cannabinoids to lipophilic pentacyclic triterpenes and polar saponins. Shikimates-phenylpropanoids include polar heterocyclic flavonoids and phenolic compounds containing at least one C3-C6 unit and usually a double bond on the propyl chain. Quercetin (19), resveratrol (24) and curcumin (27), stand out from this group for exhibiting beneficial effects on patients. Alkaloids, the minor group of potential modulators on PPARs, include berberine (30), which has been widely explored in preclinical and clinical studies for its potential beneficial effects on T2D and dyslipidemia. However, large-scale clinical trials may be warranted for the promising compounds.

Inhibition of Notch Signaling Promotes the Differentiation of Epicardial Progenitor Cells into Adipocytes

Background

The role of Notch signaling pathway in the differentiation of epicardial progenitor cells (EPCs) into adipocytes is unclear. The objective is to investigate the effects of Notch signaling on the differentiation of EPCs into adipocytes.

Methods

Frozen sections of C57BL/6J mouse hearts were used to observe epicardial adipose tissue (EAT), and genetic lineage methods were used to trace EPCs. EPCs were cultured in adipogenic induction medium with Notch ligand jagged-1 or γ-secretase inhibitor DAPT. The adipocyte markers, Notch signaling, and adipogenesis transcription factors were determined.

Results

There was EAT located at the atrial-ventricular groove in mouse. By using genetic lineage tracing methods, we found that EPCs were a source of epicardial adipocytes. EPCs had lipid droplet accumulation, and the expression of adipocyte markers FABP-4 and perilipin-1 was upregulated under adipogenic induction. Activating the Notch signaling with jagged-1 attenuated the adipogenic differentiation of EPCs and downregulated the key adipogenesis transcription factor peroxisome proliferator activated receptor-γ (PPAR-γ), while inhibiting the signaling promoted adipogenic differentiation and upregulated PPAR-γ. When blocking PPAR-γ, the role of Notch signaling in promoting adipogenic differentiation was inhibited.

Conclusions

EPCs are a source of epicardial adipocytes. Downregulation of the Notch signaling pathway promotes the differentiation of EPCs into adipocytes via PPAR-γ.

Dillenia Indica Fruit Extract Suppressed Diet-induced Obesity in Rats by Down-regulating the mRNA Level of Proadipogenic Transcription Factors and Lipid Metabolizing Enzymes

Background:

Dillenia indica (Family: Dilleniaceae) is an antioxidant-rich edible fruitbearing medicinal plant. The fruit of this plant (known as elephant apple) has many uses in traditional medicine.

Objective:

By considering its antioxidant content and ameliorating effects, this study aimed to evaluate the anti-adipogenic effects of D. indica fruit extract (DIFE) on high-fat diet (HFD) fed obese rats.

Methods:

Male Wistar rats were fed with a standard diet (SD), or high-fat diet (HFD), or HFD with 100 mg/kg or 200 mg/kg or 400 mg/kg DIFE for 8 weeks. The fruit extract was given orally by feeding gavage. The body weight, liver weight, visceral fat weight, plasma lipids, and oxidative stress-related parameters were measured. The mRNA level of different adipogenesis related transcription factors, lipogenic and lipolytic enzymes was also evaluated.

Results:

Consumption of DIFE daily (400 mg/kg) for 8 weeks resulted in a significant reduction of high-fat diet-induced body weight, liver weight, visceral fat weight, total cholesterol, and LDL-cholesterol level. High-fat diet-mediated elevation of oxidative stress markers was also lowered, with a parallel augmentation of the activities of antioxidant enzymes, due to 400 mg/kg DIFE feeding. DIFE also down-regulated the mRNA level of important pro-adipogenic factors like PPARγ, LXRα, and SREBP1c which consequently downregulated the transcript levels of lipogenic enzymes: ACC, FAS, HMGCR, and DGAT. The transcript level of lipolytic enzyme, HSL was also down-regulated in 400 mg/kg DIFE-fed rats.

Conclusion:

These findings indicate that the antioxidant-rich ethanolic extract of D. indica fruit can down-regulate the gene expression of pro-adipogenic transcription factors and lipid metabolizing enzymes and thus can suppress diet-induced obesity in Wistar rat.

Coffee and Lower Risk of Type 2 Diabetes: Arguments for a Causal Relationship

Prospective epidemiological studies concur in an association between habitual coffee consumption and a lower risk of type 2 diabetes. Several aspects of these studies support a cause–effect relationship. There is a dependency on daily coffee dose. Study outcomes are similar in different regions of the world, show no differences between sexes, between obese versus lean, young versus old, smokers versus nonsmokers, regardless of the number of confounders adjusted for. Randomized controlled intervention trials did not find a consistent impact of drinking coffee on acute metabolic control, except for effects of caffeine. Therefore, lowering of diabetes risk by coffee consumption does not involve an acute effect on the post-meal course of blood glucose, insulin or insulin resistance. Several studies in animals and humans find that the ingestion of coffee phytochemicals induces an adaptive cellular response characterized by upregulation and de novo synthesis of enzymes involved in cell defense and repair. A key regulator is the nuclear factor erythroid 2-related factor 2 (Nrf2) in association with the aryl hydrocarbon receptor, AMP-activated kinase and sirtuins. One major site of coffee actions appears to be the liver, causing improved fat oxidation and lower risk of steatosis. Another major effect of coffee intake is preservation of functional beta cell mass via enhanced mitochondrial function, lower endoplasmic reticulum stress and prevention or clearance of aggregates of misfolded proinsulin or amylin. Long-term preservation of proper liver and beta cell function may account for the association of habitual coffee drinking with a lower risk of type 2 diabetes, rather than acute improvement of metabolic control.

Precision Nutrition to Activate Thermogenesis as a Complementary Approach to Target Obesity and Associated-Metabolic-Disorders

Simple Summary

Regarding the pandemic of obesity and chronic diseases associated to metabolic alterations that occur nowadays worldwide, here, we review the most recent studies related to bioactive compounds and diet derived ingredients with potential effects to augment the systemic energy expenditure. We specifically focus in two processes: the activation of thermogenesis in adipose tissue and the enhancement of the mitochondrial oxidative phosphorylation capacity in muscles. This may provide relevant information to develop diets and supplements to conduct nutritional intervention studies with the objective to ameliorate the metabolic and chronic inflammation in the course of obesity and related disorders.

Abstract

Obesity is associated to increased incidence and poorer prognosis in multiple cancers, contributing to up to 20% of cancer related deaths. These associations are mainly driven by metabolic and inflammatory changes in the adipose tissue during obesity, which disrupt the physiologic metabolic homeostasis. The association between obesity and hypercholesterolemia, hypertension, cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM) is well known. Importantly, the retrospective analysis of more than 1000 epidemiological studies have also shown the positive correlation between the excess of fatness with the risk of cancer. In addition, more important than weight, it is the dysfunctional adipose tissue the main driver of insulin resistance, metabolic syndrome and all cause of mortality and cancer deaths, which also explains why normal weight individuals may behave as “metabolically unhealthy obese” individuals. Adipocytes also have direct effects on tumor cells through paracrine signaling. Downregulation of adiponectin and upregulation of leptin in serum correlate with markers of chronic inflammation, and crown like structures (CLS) associated to the adipose tissue disfunction. Nevertheless, obesity is a preventable risk factor in cancer. Lifestyle interventions might contribute to reduce the adverse effects of obesity. Thus, Mediterranean diet interventional studies have been shown to reduce to circulation inflammatory factors, insulin sensitivity and cardiovascular function, with durable responses of up to 2 years in obese patients. Mediterranean diet supplemented with extra-virgin olive oil reduced the incidence of breast cancer compared with a control diet. Physical activity is another important lifestyle factor which may also contribute to reduced systemic biomarkers of metabolic syndrome associated to obesity. In this scenario, precision nutrition may provide complementary approaches to target the metabolic inflammation associated to “unhealthy obesity”. Herein, we first describe the different types of adipose tissue -thermogenic active brown adipose tissue (BAT) versus the energy storing white adipose tissue (WAT). We then move on precision nutrition based strategies, by mean of natural extracts derived from plants and/or diet derived ingredients, which may be useful to normalize the metabolic inflammation associated to “unhealthy obesity”. More specifically, we focus on two axis: (1) the activation of thermogenesis in BAT and browning of WAT; (2) and the potential of augmenting the oxidative capacity of muscles to dissipate energy. These strategies may be particularly relevant as complementary approaches to alleviate obesity associated effects on chronic inflammation, immunosuppression, angiogenesis and chemotherapy resistance in cancer. Finally, we summarize main studies where plant derived extracts, mainly, polyphenols and flavonoids, have been applied to increase the energy expenditure.

Natural Extracts from White Common Bean (Phaseolus vulgaris L.) Inhibit 3T3-L1 Adipocytes Differentiation

Background: Recent studies have shown that the consumption of common bean (Phaseolus vulgaris L.) foods plays an essential role in the prevention and treatment of obesity. Methods: In this study, different natural extracts that include common bean polyphenol-rich extract (CBP), α-amylase inhibitor-rich extract (α-AIE), and non-starch polysaccharides-rich extract (NSP) were isolated. Their effects on 3T3-L1 adipocytes differentiation were evaluated, respectively. Results: The results showed that CPB reduced the lipid content in the mature adipocytes to 79.29% (150 μg/mL) and 35.13% (300 μg/mL), and α-AIE reduced it to 90.20% (2 mg/mL) and 68.28% (4 mg/mL), while NSP exhibited an auxo-action, suggesting that both CBP and a-AIE inhibited 3T3-L1 adipocytes differentiation. Additionally, CBP significantly suppressed (p < 0.05) the mRNA expression level and the protein expression level of peroxisome proliferator-activated receptor γ (PPARγ), CCAAT-enhancer-binding protein α (C/EBPα), sterol-regulatory element binding proteins 1 c (SREBP-1c), lipoprotein lipase (LPL), and fatty acid binding protein (ap2). Meanwhile, α-AIE only showed significant suppression effects on PPARγ, C/EBPα, and ap2 at the high dose of 4 mg/mL (p < 0.05). Conclusions: These findings indicate that CBP, from white common bean, might be the major component responsible for the inhibitory effects on adipocyte differentiation.

Cytotoxicity and insulin resistance reversal ability of biofunctional phytosynthesized MgO nanoparticles

The present study investigates the cytotoxicity of hexagonal MgO nanoparticles synthesized via Amaranthus tricolor leaf extract and spherical MgO nanoparticles synthesized via Amaranthus blitum and Andrographis paniculata leaf extracts. In vitro cytotoxicity analysis showed that the hexagonal MgO nanoparticles synthesized from A. tricolor extract demonstrated the least toxicity to both diabetic and non-diabetic cells at 600 μl/ml dosage. The viability of the diabetic cells (3T3-L1) after incubation with varying dosages of MgO nanoparticles was observed to be 55.3%. The viability of normal VERO cells was 86.6% and this stabilized to about 75% even after exposure to MgO nanoparticles dosage of up to 1000 μl/ml. Colorimetric glucose assay revealed that the A. tricolor extract synthesized MgO nanoparticles resulted in ~ 28% insulin resistance reversal. A reduction in the expression of GLUT4 protein at 54 KDa after MgO nanopaSrticles incubation with diabetic cells was observed via western blot analysis to confirm insulin reversal ability. Fluorescence microscopic analysis with propidium iodide and acridine orange dyes showed the release of reactive oxygen species as a possible mechanism of the cytotoxic effect of MgO nanoparticles. It was inferred that the synergistic effect of the phytochemicals and MgO nanoparticles played a significant role in delivering enhanced insulin resistance reversal capability in adipose cells.

Phenolic Compounds Reduce the Fat Content in Caenorhabditis elegans by Affecting Lipogenesis, Lipolysis, and Different Stress Responses

Supplementation with bioactive compounds capable of regulating energy homeostasis is a promising strategy to manage obesity. Here, we have screened the ability of different phenolic compounds (myricetin, kaempferol, naringin, hesperidin, apigenin, luteolin, resveratrol, curcumin, and epicatechin) and phenolic acids (p-coumaric, ellagic, ferulic, gallic, and vanillic acids) regulating C. elegans fat accumulation. Resveratrol exhibited the strongest lipid-reducing activity, which was accompanied by the improvement of lifespan, oxidative stress, and aging, without affecting worm development. Whole-genome expression microarrays demonstrated that resveratrol affected fat mobilization, fatty acid metabolism, and unfolded protein response of the endoplasmic reticulum (UPRER), mimicking the response to calorie restriction. Apigenin induced the oxidative stress response and lipid mobilization, while vanillic acid affected the unfolded-protein response in ER. In summary, our data demonstrates that phenolic compounds exert a lipid-reducing activity in C. elegans through different biological processes and signaling pathways, including those related with lipid mobilization and fatty acid metabolism, oxidative stress, aging, and UPR-ER response. These findings open the door to the possibility of combining them in order to achieve complementary activity against obesity-related disorders.

Flavonoids as antiobesity agents: A review

Obesity is a global health problem that affects all age groups in both developing and developed countries. In recent years, the prevalence of overweight and obesity has reached pandemic levels, resulting in a dramatic increase in the incidence of various comorbidities, such as cardiovascular diseases, type 2 diabetes, and cancer, consequently leading to massive health and socioeconomic burdens. Together with lifestyle changes, antiobesity pharmacotherapy is gaining momentum as an adjunctive treatment. However, the available pharmacological approaches have limited use owing to either significant adverse effects or low efficacy. Over the years, natural products have been an important source of lead compounds for drug discovery. Among these, flavonoids are associated with important biological effects and health-promoting activities. In this review, we discuss the modulatory effects of flavonoids on obesity and their potential mechanisms of action. The literature strongly suggests that most common flavonoids demonstrate a pronounced effect on obesity as shown by their ability to lower body weight, fat mass, and plasma triglycerides/cholesterol, both in in vitro and in vivo models. The impact of flavonoids on obesity can be observed through different mechanisms: reducing food intake and fat absorption, increasing energy expenditure, modulating lipid metabolism, or regulating gut microbiota profile. A better understanding of the known antiobesity mechanisms of flavonoids will enable their potential use to treat this medical condition. Therefore, this review focuses on the putative biological mechanisms through which flavonoids may prevent or treat obesity and highlights new perspectives on future pharmacological use.

Anthocyanin-Enriched Riceberry Rice Extract Inhibits Cell Proliferation and Adipogenesis in 3T3-L1 Preadipocytes by Downregulating Adipogenic Transcription Factors and Their Targeting Genes

Riceberry rice (Oryza sativa L.) is a new pigmented variety of rice from Thailand. Despite its high anthocyanin content, its effect on adipogenesis and adipocyte function remains unexplored. We investigated whether Riceberry rice extract (RBE) impacted cell proliferation by examining viability and cell cycle, using preadipocyte 3T3-L1 cells. To test RBE's effect on adipocyte formation, cells were cultured in adipogenic medium supplemented with extract and adipocyte number and triglyceride levels were quantified. Furthermore, Akt1 phosphorylation along with RT-qPCR and intracellular calcium imaging were performed to obtain an insight into its mechanism of action. The effect of RBE on adipocyte function was investigated using glucose uptake and lipolysis assays. Treatment of cells with RBE decreased preadipocyte number without cytotoxicity despite inducing cell cycle arrest (p < 0.05). During adipogenic differentiation, RBE supplementation reduced adipocyte number and triglyceride accumulation by downregulating transcription factors (e.g., PPARγ, C/EBPα, and C/EBPβ) and their target genes (p < 0.05). The Akt1 phosphorylation was decreased by RBE but insignificance, however, the extract failed to increase intracellular calcium signals. Finally, the treatment of adipocytes with RBE reduced glucose uptake by downregulating Glut4 mRNA expression and enhanced isoproterenol-induced lipolysis (p < 0.05). These findings suggest that RBE could potentially be used in the treatment of obesity by inhibiting adipocyte formation and proliferation.

Viburnum opulus L. Juice Phenolics Inhibit Mouse 3T3-L1 Cells Adipogenesis and Pancreatic Lipase Activity

Viburnum opulus L. fruit is a rich source of phenolic compounds that may be involved in the prevention of metabolic diseases. The purpose of this study was to determine the effects of Viburnum opulus fresh juice (FJ) and juice purified by solid-phase extraction (PJ) on the adipogenesis process with murine 3T3-L1 preadipocyte cell line and pancreatic lipase activity in triolein emulsion, as well as their phenolic profiles by UPLC/Q-TOF-MS. Decrease of lipids and triacylglycerol accumulation in differentiated 3T3-L1 cells were in concordance with downregulation of the expression of peroxisome proliferator-activated receptor-gamma (PPARγ), CCAAT/enhancer-binding protein alpha (C/EBPβ/α), and sterol regulatory element-binding protein 1c (SREBP-1c). Furthermore, regulation of PPARγ-mediated β-lactamase expression by V. opulus components in reporter gene assay, as well as their binding affinity to ligand-binding domain of PPARγ, were tested. In addition, the levels of enzymes involved in lipid metabolism, like fatty acid synthase (FAS) or acetyl-CoA carboxylase (ACC), were decreased, along with inflammatory cytokines, like tumor necrosis factorα (TNFα), interleukin-6 (Il-6) and leptin. Moreover, FJ and PJ were able to inhibit pancreatic lipase, which potentially could reduce the fat absorption from the intestinal lumen and the storage of body fat in the adipose tissues. Thirty-two phenolic compounds with chlorogenic acid as the dominant compound were identified in PJ which revealed significant biological activity. These data contribute to elucidate V. opulus juice phenolic compounds’ molecular mechanism in adipogenesis regulation in 3T3-L1 cells and dietary fat lipolysis.

A combination of borage seed oil and quercetin reduces fat accumulation and improves insulin sensitivity in obese rats

The metabolic properties of omega-6 fatty acid consumption are being increasingly accepted. We had previously observed that supplementation with a borage seed oil (BSO), as a source of linoleic (18:2n-6; LA) and gamma-linolenic (18:3n-6; GLA) acids, reduces body weight and visceral adiposity and improves insulin sensitivity in a diet-induced obesity model of Wistar rats. Here, it was investigated whether the anti-obesogenic properties of BSO could be maintained in a pre-obese model of rats, and if these effects are enhanced by a combination with low doses of quercetin, together with its potential role in the regulation of the adipocyte biology. The combination of BSO and quercetin during 8 weeks was able to ameliorate glucose intolerance and insulin resistance, and to improve liver steatosis. Although no effects were observed on body weight, animals supplemented with this combination exhibited a lower proportion of visceral adiposity. In addition, in vitro differentiation of epididymal adipose-precursor cells of the BSO-treated animals exhibited a down-regulation of Fasn, Glut4, Pparg and Srebp1 genes, in comparison with the control group. Finally, in vitro evaluation of the components of BSO demonstrated that the anti-adipogenic activity of quercetin was significantly potentiated by the combination with both LA and GLA through the down-regulation of different adipogenesis-key genes in 3T3-L1 cells. All these data suggest that omega-6 fatty acids LA and GLA, and their natural sources such as BSO, could be combined with quercetin to potentiate their effects in the prevention of the excess of adiposity and the insulin resistance.

Structure-based drug design of peroxisome proliferator-activated receptor gamma inhibitors: ferulic acid and derivatives

Peroxisome proliferator-activated receptor gamma (PPARγ), ligand-activated transcription factor, is a key modulator of genes considered in diabetes development as well as treatment. Adipogenesis differentiation through PPARγ, CCAAT-enhancer protein alpha (C/EBPα) is identified as a critical mechanism in fat accumulation and weight gain. Polyphenols studied against adipocyte differentiation is taken up for consistent support and drug discovery. Structure-based drug design found useful to distinguish the underlying mechanism of receptor-ligand interaction and function. In this work, phenolic acids, ferulic acid and its derivatives are used as ligands. Molecular parameters have been set to filter and sort the 34 derivatives from ZINC and PubChem databases. Besides, for affinity and activity identification, troglitazone and resveratrol co-crystallized ligands have been studied. Absorption, distribution, metabolism, elimination and toxicity, density functional theory, highest occupied molecular orbital-lowest unoccupied molecular orbital values and docking scores define the drug candidate as a potential inhibitor. Residues Ser 342 and Arg 280 bind with the ligands by forming hydrogen bonds and hydrophobic contacts. Based on the docking score, pharmacophore properties and functional energy values of the top six compounds are chosen for molecular dynamics and simulation. Consistency and stability maintained throughout the simulation up to 50 ns were observed. Free binding energy values and standard deviation of receptor and ligand calculated using molecular mechanics-generalized Born and surface area solvation method (MM_GBSA) is found significant. Therefore, ferulic acid derivatives and phenolic acids could be a potential inhibitor for adipocyte differentiation and lipid accumulation.Communicated by Ramaswamy H. Sarma.

Stearoyl-CoA Desaturase-1 Enzyme Inhibition by Grape Skin Extracts Affects Membrane Fluidity in Human Colon Cancer Cell Lines

The polyphenolic compounds present in grape extracts have chemopreventive and anticancer properties. Here, we studied the ability of two grape skin extracts (GSEs), Autumn Royal and Egnatia, to influence the cell motility and membrane fluidity regulated by the enzyme Stearoyl-CoA desaturase-1 (SCD1) which increases with the cancer aggressiveness. Caco2 and SW480 human colon cancer cell lines were treated with increasing concentrations of GSEs to evaluate cell proliferation and motility. SCD1 levels were evaluated in both treated cell lines, by membrane lipidomic analysis conducted by gas chromatography. The expression levels of SCD1 and other factors involved in the reorganization of the cytoskeleton and focal adhesions were assessed by Real-time PCR, Western Blotting, and Immunofluorescence staining. High-performance liquid chromatography (HPLC) analyses were performed to determine the phenolic composition in the GSEs, finding them more expressed in Autumn Royal than in Egnatia. Both treatments reduced the levels of SCD1, phospho-Rac1/Cdc42/Rac1/Cdc42 ratio, Cofilin, Vimentin, and phospho-Paxillin especially in Caco2 compared to SW480, showing a different behavior of the two cell lines to these natural compounds. Our findings show that GSEs block the cell migration and membrane fluidity through a new mechanism of action involving structural cellular components.

Phenolic Compounds with Antioxidant Properties from Canola Meal Extracts Inhibit Adipogenesis

The extraction of phenolic compounds from canola meal produces functional health products and renders the canola meal a more digestible animal feed. The extracted phenolics may have novel bioactivity worth investigation. In this study, several solvents were evaluated for their ability to extract phenolic compounds from canola meal: water (WE) and various 80% organic solvent/water mixtures of methanol (ME), acetone (AE), ethanol (EE), butanol (BE), chloroform (CE) and hexane (HE). The in vitro antioxidant and anti-obesity properties of various extracts were investigated. Anti-obesity properties were studied using adipogenic differentiation inhibition of a murine mesenchymal stem cell line (C3H10T1/2) and a pancreatic lipase inhibition assay. AE, ME, and BE showed significant (p < 0.05) adipogenesis and pancreatic lipase inhibitory activities and may have more pharmacological properties. AE down-regulated the gene expression of the major adipogenic transcription factor, peroxisome proliferator-activated receptor gamma (PPARγ), correlating to phenolic content in a dose-dependent manner. The chemical characterization of AE revealed the presence of sinapic acid, ferulic acid, and kaempferol derivatives as main bioactive phenols.

Hesperidin: A Therapeutic Agent For Obesity

Obesity is a chronic metabolic disease caused by multiple factors and is considered to be a risk factor for type 2 diabetes, cardiovascular disease, hypertension, stroke and various cancers. Hesperidin, a flavanone glycoside, is a natural phenolic compound with a wide range of biological effects. Mounting evidence has demonstrated that hesperidin possesses inhibitory effect against obesity diseases. Our review discusses mechanisms of hesperidin in the treatment of obesity. Hesperidin regulates lipid metabolism and glucose metabolism by mediating AMPK and PPAR signaling pathways, directly regulates antioxidant index and anti-apoptosis, and indirectly mediates NF-κB signaling pathway to regulate inflammation to play a role in the treatment of obesity. In addition, hesperidin-enriched dietary supplements can significantly improve symptoms such as postprandial hyperglycemia and hyperlipidemia. Further clinical trials are also required for confirming lipid-lowering efficacy of this natural flavonoid and evaluating its safety profile.

The Effect of Curcumin on the Differentiation of Mesenchymal Stem Cells into Mesodermal Lineage

Curcumin has been placed at the forefront of the researcher's attention due to its pleiotropic pharmacological effects and health benefits. A considerable volume of articles has pointed out curcumin's effects on the fate of stem cell differentiation. In this review, a descriptive mechanism of how curcumin affects the outcome of the differentiation of mesenchymal stem cells (MSCs) into the mesodermal lineage-i.e., adipocyte, osteocyte, and chondrocyte differentiation-is compiled from the literature. The sections include the mechanism of inhibition or induction of MSCs differentiation to each lineage, their governing molecular mechanisms, and their signal transduction pathways. The effect of different curcumin doses and its structural modifications on the MSCs differentiation is also discussed.

Adipose tissue as a possible therapeutic target for polyphenols: A case for Cyclopia extracts as anti-obesity nutraceuticals

Obesity is a significant contributor to increased morbidity and premature mortality due to increasing the risk of many chronic metabolic diseases such as type 2 diabetes, cardiovascular disease and certain types of cancer. Lifestyle modifications such as energy restriction and increased physical activity are highly effective first-line treatment strategies used in the management of obesity. However, adherence to these behavioral changes is poor, with an increased reliance on synthetic drugs, which unfortunately are plagued by adverse effects. The identification of new and safer anti-obesity agents is thus of significant interest. In recent years, plants and their phenolic constituents have attracted increased attention due to their health-promoting properties. Amongst these, Cyclopia, an endemic South African plant commonly consumed as a herbal tea (honeybush), has been shown to possess modulating properties against oxidative stress, hyperglycemia, and obesity. Likewise, several studies have reported that some of the major phenolic compounds present in Cyclopia spp. exhibit anti-obesity effects, particularly by targeting adipose tissue. These phenolic compounds belong to the xanthone, flavonoid and benzophenone classes. The aim of this review is to assess the potential of Cyclopia extracts as an anti-obesity nutraceutical as underpinned by in vitro and in vivo studies and the underlying cellular mechanisms and biological pathways regulated by their phenolic compounds.

Relationship of the Phytochemicals from Coffee and Cocoa By-Products with their Potential to Modulate Biomarkers of Metabolic Syndrome In Vitro

This study aimed to compare the phytochemicals from coffee and cocoa by-products and their relationship with the potential for reducing markers of inflammation, oxidative stress, adipogenesis, and insulin resistance in vitro. We characterized the phytochemical profile of extracts from coffee husk, coffee silverskin, and cocoa shell and evaluated their in vitro biological activity in RAW264.7 macrophages and 3T3-L1 adipocytes. Pearson correlations and principal component regressions were performed to find the contribution of phytochemicals and underlying mechanisms of action. Coffee husk and silverskin extracts were mainly composed of caffeine and chlorogenic acid. Major components in cocoa shell included theobromine and protocatechuic acid. Both coffee and cocoa by-product extracts effectively reduced inflammatory markers in macrophages and adipocytes (NO, PGE2, TNF-α, MCP-1, and IL-6) and the production of reactive oxygen species (21.5-66.4%). Protocatechuic and chlorogenic acids, together with caffeine, were suggested as main contributors against inflammation and oxidative stress. Furthermore, extracts reduced lipid accumulation (4.1-49.1%) in adipocytes by regulating lipolysis and inducing adipocyte browning. Gallic and chlorogenic acids were associated with reduced adipogenesis, and caffeine with adipocyte browning. Extracts from coffee and cocoa by-products also modulated the phosphorylation of insulin receptor signaling pathway and stimulated GLUT-4 translocation (52.4-72.9%), increasing glucose uptake. The insulin-sensitizing potential of the extracts was mainly associated with protocatechuic acid. For the first time, we identified the phytochemicals from coffee and cocoa by-products and offered new insights into their associations with biomarkers of inflammation, oxidative stress, adipogenesis, and insulin resistance in vitro.

Identification of Pyrvinium, an Anthelmintic Drug, as a Novel Anti-Adipogenic Compound Based on the Gene Expression Microarray and Connectivity Map

Obesity is a serious health problem, while the current anti-obesity drugs are not very effective. The Connectivity Map (C-Map), an in-silico drug screening approach based on gene expression profiles, has recently been indicated as a promising strategy for drug repositioning. In this study, we performed mRNA expression profile analysis using microarray technology and identified 435 differentially expressed genes (DEG) during adipogenesis in both C3H10T1/2 and 3T3-L1 cells. Then, DEG signature was uploaded into C-Map, and using pattern-matching methods we discovered that pyrvinium, a classical anthelminthic, is a novel anti-adipogenic differentiation agent. Pyrvinium suppressed adipogenic differentiation in a dose-dependent manner, as evidenced by Oil Red O staining and the mRNA levels of adipogenic markers. Furthermore, we identified that the inhibitory effect of pyrvinium was resulted primarily from the early stage of adipogenesis. Molecular studies showed that pyrvinium downregulated the expression of key transcription factors C/EBPa and PPARγ. The mRNA levels of notch target genes Hes1 and Hey1 were obviously reduced after pyrvinium treatment. Taken together, this study identified many differentially expressed genes involved in adipogenesis and demonstrated for the first time that pyrvinium is a novel anti-adipogenic compound for obesity therapy. Meanwhile, we provided a new strategy to explore potential anti-obesity drugs.