Flavonoid derivative (Fla-CN) inhibited adipocyte differentiation via activating AMPK and up-regulating microRNA-27 in 3T3-L1 cells

Effects of quercetin and genistein on egg quality, lipid profiles, and immunity in laying hens

BACKGROUND

After the peak laying stage, laying hens become susceptible to lipid accumulation and inflammatory reactions. The objective of this experiment was to examine the impact of quercetin and genistein on egg quality and lipid profiles in laying hens. A total of 240 Hy-Line Brown hens were randomly assigned to three dietary treatments. Each treatment had eight replicates, with ten hens in each replicate, and the hens were aged between 46 and 56 weeks. The test diets consisted of a corn-soybean meal-based basal diet, a basal diet supplemented with 300 mg kg-1 quercetin, and a basal diet supplemented with 300 mg kg-1 quercetin and 40 mg kg-1 genistein.

RESULTS

Results showed that, separately, supplemental quercetin significantly improved egg quality (eggshell strength, albumen height, and Haugh unit, P < 0.05) and reduced the deposition of abdominal fat (P < 0.05). Our findings also showed that, separately or as a combination, supplemental quercetin and genistein significantly increased eggshell thickness (P < 0.05), decreased the levels of lipids in serum (low-density lipoprotein cholesterol, total cholesterol, total triglycerides, and non-esterified fatty acids, P < 0.05) and significantly increased serum immunoglobulins A and G (P < 0.05), and promoted the expression of splenic immune-related genes (IgA and IL-4, P < 0.05).

CONCLUSION

This study confirmed that supplemental quercetin and genistein, either separately or in combination, can enhance eggshell thickness, lipid profiles, and immune function in aging hens. Moreover, both quercetin alone and quercetin + genistein exhibited similar abilities to lower lipid levels and improve immune function. © 2023 Society of Chemical Industry.

Role of MicroRNAs in Dietary Interventions for Obesity and Obesity-Related Diseases

Obesity and related metabolic syndromes pose a serious threat to human health and quality of life. A proper diet is a safe and effective strategy to prevent and control obesity, thus maintaining overall health. However, no consensus exists on the connotations of proper diet, and it is attributed to various factors, including "nutritional dark matter" and the "matrix effect" of food. Accumulating evidence confirms that obesity is associated with the in vivo levels of miRNAs, which serve as potential markers and regulatory targets for obesity onset and progression; food-derived miRNAs can regulate host obesity by targeting the related genes or gut microbiota across the animal kingdom. Host miRNAs mediate food nutrient-gut microbiota-obesity interactions. Thus, miRNAs are important correlates of diet and obesity onset. This review outlines the recent findings on miRNA-mediated food interventions for obesity, thereby elucidating their potential applications. Overall, we provide new perspectives and views on the evaluation of dietary nutrition, which may bear important implications for dietary control and obesity prevention.

New Insights into Adipose Tissue Macrophages in Obesity and Insulin Resistance

Obesity has become a worldwide epidemic that poses a severe threat to human health. Evidence suggests that many obesity comorbidities, such as type 2 diabetes mellitus, steatohepatitis, and cardiovascular diseases, are related to obesity-induced chronic low-grade inflammation. Macrophages are the primary immune cells involved in obesity-associated inflammation in both mice and humans. Intensive research over the past few years has yielded tremendous progress in our understanding of the additional roles of adipose tissue macrophages (ATMs) beyond classical M1/M2 polarization in obesity and related comorbidities. In this review, we first characterize the diverse subpopulations of ATMs in the context of obesity. Furthermore, we review the recent advance on the role of the extensive crosstalk between adipocytes and ATMs in obesity. Finally, we focus on the extended crosstalk within adipose tissue between perivascular mesenchymal cells and ATMs. Understanding the pathological mechanisms that underlie obesity will be critical for the development of new intervention strategies to prevent or treat this disease and its associated co-morbidities.

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.

Advance toward isolation, extraction, metabolism and health benefits of kaempferol, a major dietary flavonoid with future perspectives

As a major ubiquitous secondary metabolite, flavonoids are widely distributed in planta. Among flavonoids, kaempferol is a typical natural flavonol in diets and medicinal plants with myriad bioactivities, such as anti-inflammatory activity, anti-cancer activity, antioxidant activity, and anti-diabetic activity. However, the natural sources, absorption and metabolism as well as the bioactivities of kaempferol have not been reviewed comprehensively and systematically. This review highlights the latest research progress and the effect of kaempferol in the prevention and treatment of various chronic diseases, as well as its protective health effects, and provides a theoretical basis for future research to be used in nutraceuticals. Further, comparison of the different extraction and analytical methods are presented to highlight the most optimum for PG recovery and its detection in plasma and body fluids. Such review aims at improving the value-added applications of this unique dietary bioactive flavonoids at commercial scale and to provide a reference for its needed further development.

The Inhibitory Effects of Juglanin on Adipogenesis in 3T3-L1 Adipocytes

INTRODUCTION

Deregulation of adipogenesis plays an important role in obesity and other metabolism disorders. PPAR, C/EBP and SREBP1c are key transcriptional factors involved in adipogenesis and lipogenesis. Juglanin is a natural compound belonging to flavonoids, and it has been reported that juglanin has a potent inhibitory effect on inflammation and certain type of cancers. However, the effects of juglanin in adipogenesis have not been reported before.

MATERIALS AND METHODS

3T3-L1 preadipocytes were incubated with differentiation induction medium in the presence or absence of 0.5, 2.5, or 5 µM juglanin for an 8-day differentiation period. The lipid droplets accumulated in the cytoplasm were monitored by Oil Red O staining on days 0, 2, 5, and 8. The regulatory effects of juglanin on adipogenesis-related genes and proteins were investigated by real-time polymerase chain reaction and Western blot analysis.

RESULTS

Juglanin significantly decreased lipid accumulation in differentiated adipocytes. Our findings show that juglanin reduced the expression of C/EBPα, C/EBPβ, and SREBP-1c without affecting PPARα or PPARγ expression. Additionally, juglanin increased the activation of the SIRT1/AMPK signaling pathway through the phosphorylation of AMPKα. Finally, we performed an AMPK inhibitor experiment, which revealed that the inhibitory effects of juglanin on adipogenesis are mediated through AMPK.

DISCUSSION

Juglanin can prevent adipogenesis by suppressing lipid accumulation and the differentiation of preadipocytes. The mechanism of juglanin regulating adipogenesis requires further investigation. Future clinical study in vivo could shed more light on its implication in modulating obesity and metabolic disorders.

Regulatory microRNAs in Brown, Brite and White Adipose Tissue

MicroRNAs (miRNAs) constitute a class of short noncoding RNAs which regulate gene expression by targeting messenger RNA, inducing translational repression and messenger RNA degradation. This regulation of gene expression by miRNAs in adipose tissue (AT) can impact on the regulation of metabolism and energy homeostasis, particularly considering the different types of adipocytes which exist in mammals, i.e., white adipocytes (white AT; WAT), brown adipocytes (brown AT; BAT), and inducible brown adipocytes in WAT (beige or brite or brown-in-white adipocytes). Indeed, an increasing number of miRNAs has been identified to regulate key signaling pathways of adipogenesis in BAT, brite AT, and WAT by acting on transcription factors that promote or inhibit adipocyte differentiation. For example, MiR-328, MiR-378, MiR-30b/c, MiR-455, MiR-32, and MiR-193b-365 activate brown adipogenesis, whereas MiR-34a, MiR-133, MiR-155, and MiR-27b are brown adipogenesis inhibitors. Given that WAT mainly stores energy as lipids, whilst BAT mainly dissipates energy as heat, clarifying the effects of miRNAs in different types of AT has recently attracted significant research interest, aiming to also develop novel miRNA-based therapies against obesity, diabetes, and other obesity-related diseases. Therefore, this review presents an up-to-date comprehensive overview of the role of key regulatory miRNAs in BAT, brite AT, and WAT.

Inhibitory Effects of Twenty-Nine Compounds From Potentilla longifolia on Lipid Accumulation and Their Mechanisms in 3T3-L1 Cells

Potentilla longifolia Willd. ex D.F.K.Schltdl., which is a kind of traditional Chinese herb, is often referred to as "Ganyancao" in China, which means "the herb is effective in the treatment of liver inflammation". Three new (ganyearmcaoosides A and B and ganyearmcaoic acid A; 1-3) and 26 known compounds (4-29) were isolated from the 95% ethanol extract of the dried aerial parts of this plant, of which 21 were isolated for the first time from this plant. The chemical structures of these compounds were elucidated using NMR and HR-ESI-MS analysis. The inhibitory effects of the 29 compounds with safe concentrations on the lipid accumulation in 3T3-L1 cells were evaluated using photographic and quantitative assessments of lipid contents by Oil Red O staining, and measurement of the triglyceride levels. Comprehensive analysis showed that compound 12 (3,8-dimethoxy-5,7,4'- trihydroxyflavone) showed the best inhibitory effect on lipid accumulation such as reducing the accumulation of oil droplets and triglyceride level, and was superior to the reference in positive control. Western blot analysis and RT-PCR results showed that compound 12 enhanced the phosphorylations of AMPK and ACC, and inhibited the expressions of adipogenesis-related proteins or genes including SREBP1c, FAS, SCD1, GPAT, PPARγ and C/EBPα, and thereby significantly inhibited lipid accumulation in a concentration-dependent manner. P. longifolia and its bioactive compounds could be promising as potential therapeutic agents for diseases related to lipid accumulation in the future.

Inhibitory effects of compounds from the roots of Potentilla longifolia on lipid accumulation

Potentilla longifolia is a kind of Chaoyao medicine, which is a branch of traditional Chinese medicine. The plant is often referred to as ganyancao or ganyearmcao, which means that it has a significant therapeutic effect on liver inflammation. In previous experiments, we found that a water extract of ganyearmcao inhibited lipid accumulation. In the present study, we isolated one new (ganyearmcaoone A, 1) and eight known compounds (2–9) from a water extract of the dried roots of ganyearmcao; all of the compounds were isolated for the first time from this medicinal plant. We elucidated the chemical structures of these compounds using comprehensive analyses of HR-ESI-MS and 1D, 2D NMR. We evaluated the inhibitory effects of the nine compounds on lipid accumulation in 3T3-L1 cells; we did so using photographic and quantitative assessments of the lipid content with oil red O staining and by measuring triglyceride levels. Compared with the control, compounds 6 and 9 significantly inhibited differentiation of 3T3-L1 cells and lipid accumulation. Compound 1 showed potential inhibitory effects on lipid accumulation. Molecular docking results indicated that compounds 6 and 9 may efficiently bind to AMPK and its downstream kinase (SCD1), thereby inhibiting lipid accumulation. Our results demonstrate that ganyearmcao and its components may play an important role in treating diseases related to lipid accumulation in the future.

Long non-coding RNA HCP5 serves as a ceRNA sponging miR-17-5p and miR-27a/b to regulate the pathogenesis of childhood obesity via the MAPK signaling pathway

Background This study aimed to investigate the completing endogenous RNA (ceRNA) network involved in childhood obesity. Methods The microarray dataset GSE9624 was downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed long non-coding RNAs (lncRNAs) (DELs) and messenger RNAs (DEMs) were isolated between the childhood obesity and non-obesity tissue samples. Then, Gene Ontology (GO) functional and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of isolated DEMs were performed. DELs and DEMs targeted miRNAs were predicted to construct a ceRNA regulatory network. Finally, critical lncRNAs were validated in another dataset. Results A total of 1257 differentially expressed RNAs were screened, including 28 lncRNAs and 1229 mRNAs. In addition, these RNAs were mainly involved in defense response, cell cycle, mitogen-activated protein kinase (MAPK) signaling pathway, apoptosis, etc. Three lncRNAs (human leukocyte antigen complex 5 [HCP5], long intergenic non-protein coding RNA 839 [LINC00839] and receptor activity modifying protein 2 [RAMP2-AS1]) and two related miRNAs (hsa-miR-17-5p and hsa-miR-27a/b-3p) were identified as key RNAs in childhood obesity. Specifically, lncRNA HCP5 interacted with miR-17-5p and miR-27a/b to regulate nemo-like kinase (NLK) and Ras-related protein 2 (RRAS2) via the MAPK signaling pathway. Finally, four genes (RRAS2, NLK, bcl2/adenovirus E1B protein-interacting protein 3 [BNIP3] and phorbol-12-myristate-13-acetate-induced protein 1 [PMAIP1]) targeted by miRNAs were predicted as critical genes and might be novel diagnostic biomarkers of childhood obesity. Conclusions lncRNA HCP5 could serve as a ceRNA sponging miR-17-5p and miR-27a/b to regulate the pathogenesis of childhood obesity via NLK and RRAS2 in the MAPK signaling pathway.

Glucose Tolerance-Improving Activity of Helichrysoside in Mice and Its Structural Requirements for Promoting Glucose and Lipid Metabolism

An acylated flavonol glycoside, helichrysoside, at a dose of 10 mg/kg/day per os for 14 days, improved the glucose tolerance in mice without affecting the food intake, visceral fat weight, liver weight, and other plasma parameters. In this study, using hepatoblastoma-derived HepG2 cells, helichrysoside, trans-tiliroside, and kaempferol 3-O-β-d-glucopyranoside enhanced glucose consumption from the medium, but their aglycones and p-coumaric acid did not show this activity. In addition, several acylated flavonol glycosides were synthesized to clarify the structural requirements for lipid metabolism using HepG2 cells. The results showed that helichrysoside and related analogs significantly inhibited triglyceride (TG) accumulation in these cells. The inhibition by helichrysoside was more potent than that by other acylated flavonol glycosides, related flavonol glycosides, and organic acids. As for the TG metabolism-promoting activity in high glucose-pretreated HepG2 cells, helichrysoside, related analogs, and their aglycones were found to significantly reduce the TG contents in HepG2 cells. However, the desacyl flavonol glycosides and organic acids derived from the acyl groups did not exhibit an inhibitory impact on the TG contents in HepG2 cells. These results suggest that the existence of the acyl moiety at the 6′′ position in the D-glucopyranosyl part is essential for glucose and lipid metabolism-promoting activities.

Oral Administration of Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032 with Cinnamomi Ramulus Extract Reduces Diet-Induced Obesity and Modulates Gut Microbiota

Obesity is a major health issue worldwide, and is associated with many diseases including type 2 diabetes. In this study, we evaluated the anti-obesity effects of combinations of two lactic acid bacteria (LAB), Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032, and Cinnamomi Ramulus (CR) extract, and explored the mechanism through which they modulate gut microbiota using diet-induced obese mice. Male C57BL/6J mice were randomly divided into five groups that received a high-fat diet (HFD), HFD and LAB (HFD+LAB), HFD and CR extract (HFD+CR), HFD with LAB and CR extract (HFD+LAB+CR), or normal diet for 10 weeks. The mice in the HFD+LAB+CR group showed significant reductions in body weight gain, in particular epididymal fat and liver, blood leptin levels, and an increase in the levels of blood adiponectin. In addition, the LAB and CR extract altered the gut microbiota, mainly increasing the alpha diversity. These results demonstrate that a mixture of two LAB (Lactobacillus curvatus HY7601 and Lactobacillus plantarum KY1032) and CR extracts alleviate HFD-induced obesity, and has potential of being used as a strategy for the treatment of obesity.

Bromophenol (5-bromo-3,4-dihydroxybenzaldehyde) isolated from red alga Polysiphonia morrowii inhibits adipogenesis by regulating expression of adipogenic transcription factors and AMP-activated protein kinase activation in 3T3-L1 adipocytes

The aim of the present study was to investigate the effect of 5-bromo-3,4-dihydroxybenzaldehyde (BD) isolated from Polysiphonia morrowii on adipogenesis and differentiation of 3T3-L1 preadipocytes into mature adipocytes and its possible mechanism of action. Levels of lipid accumulation and triglyceride were significantly lower in BD treated cells than those in untreated cells. In addition, BD treatment reduced protein expression levels of peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding proteins α, and sterol regulatory element-binding protein 1 compared with control (no treatment). It also reduced expression levels of adiponectin, leptin, fatty acid synthase, and fatty acid binding protein 4. AMP-activated protein kinase activation was found to be one specific mechanism involved in the effect of BD. These results demonstrate that BD possesses inhibitory effect on adipogenesis through activating AMP-activated protein kinase signal pathway.

Synergistic Inhibitory Effects of Acacetin and 11 Other Flavonoids Isolated from Artemisia sacrorum on Lipid Accumulation in 3T3-L1 Cells

Artemisia sacrorum Ledeb., a Compositae forage plant in China, has been found to have an inhibitory effect on lipid accumulation. We selected 12 flavonoids, which we had isolated from A. sacrorum and had the potential to inhibit lipid accumulation in the literature or in our preliminary experiments, and grouped them into 11 compound combinations; we investigated their synergistic inhibitory effects on lipid accumulation in 3T3-L1 cells. In screening experiments, Oil-Red O staining, triglyceride levels, and lipid accumulation levels all indicated that combined acacetin and apigenin displayed a significant synergistic inhibitory effect and the best repeatability. Subsequent research showed that this combination could synergistically promote the phosphorylations of AMPK and ACC. Furthermore, to a different extent, that combination had significant synergistic inhibitory effects on various genes or proteins related to adipogenesis and lipogenesis. Thus, that combination could significantly reduce triglyceride levels and lipid accumulation compared with acacetin or apigenin acting alone.

A Review on the Dietary Flavonoid Tiliroside

Among flavonoid derivatives, tiliroside is a flavonoid contained in several edible plants or specific plant parts (fruits, leaves, or roots). These parts are often widely used as both food and medicines, in the treatment of various ailments and, in some cases, as food supplements. Considering the easy access to many publications concerning tiliroside and the lack of a review that summarizes the current progress in studies on its safety, efficacy, and presence in the plant kingdom, we present here a review paper on tiliroside and its principal derivatives. The paper also highlights the basic knowledge regarding this molecule, its derivatives, and the analytical approaches used for extraction and quantification, as well as reports on the biological activities against different key enzymes linked to various human diseases. The reported information is also devoted to highlighting the concept "learn from nature to discover new products," particularly in the development of new drugs, food supplements, and nutraceuticals, starting from a natural lead compound such as tiliroside and improving its biological activities (and selectivities) against a specific target for therapeutic purposes.

Potential miRNA involvement in the anti-adipogenic effect of resveratrol and its metabolites

OBJECTIVE

Scientific research is constantly striving to find molecules which are effective against excessive body fat and its associated complications. Taking into account the beneficial effects that resveratrol exerts on other pathologies through miRNA, the aim of the present work was to analyze the possible involvement of miRNAs in the regulation of adipogenic transcription factors peroxisome proliferator-activated receptor γ (pparγ), CCAAT enhancer-binding proteins α and β (cebpβ and cebpα) induced by resveratrol and its metabolites.

METHODS

3T3-L1 maturing pre-adipocytes were treated during differentiation with 25 μM of trans-resveratrol (RSV), trans-resveratrol-3-O-sulfate (3S), trans-resveratrol-3'-O-glucuronide (3G) and trans-resveratrol-4'-O-glucuronide (4G). After computational prediction and bibliographic search of miRNAs targeting pparγ, cebpβ and cebpα, the expression of microRNA-130b-3p (miR-130b-3p), microRNA-155-5p (miR-155-5p), microRNA-27b-3p (miR-27b-3p), microRNA-31-5p (miR-31-5p), microRNA-326-3p (miR-326-3p), microRNA-27a-3p (miR-27a-3p), microRNA-144-3p (miR-144-3p), microRNA-205-5p (miR-205-5p) and microRNA-224-3p (miR-224-3p) was analyzed. Moreover, other adipogenic mediators such as sterol regulatory element binding transcription factor 1 (srebf1), krüppel-like factor 5 (klf5), liver x receptor α (lxrα) and cAMP responding element binding protein 1 (creb1), were measured by Real Time RT-PCR. As a confirmatory assay, cells treated with RSV were transfected with anti-miR-155 in order to measure cebpβ gene and protein expressions.

RESULTS

Of the miRNAs analyzed only miR-155 was modified after resveratrol and glucuronide metabolite treatment. In transfected cells with anti-miR-155, RSV did not reduce cebpβ gene and protein expression. 3S decreased gene expression of creb1, klf5, srebf1 and lxrα.

CONCLUSIONS

While RSV and glucuronide metabolites exert their inhibitory effect on adipogenesis through miR-155 up-regulation, the anti-adipogenic effect of 3S is not mediated via miRNAs.

Adipogenic miR-27a in adipose tissue upregulates macrophage activation via inhibiting PPARγ of insulin resistance induced by high-fat diet-associated obesity

Chronic low degree inflammation caused by macrophage activation is a crucial factor underlying insulin resistance induced by obesity. To illustrate the mechanism of regulating of macrophage activation in adipose tissue, the role of adipogenic miR-27a activating M1 macrophage polarization via blocking PPARγ was evaluated. Obese mice model and miR-27a overexpression or knockdown mice model were established and related biochemical index were examined. Raw264.7 and 3T3-L1 were cultured and co-cultured for mimicking the microenvironment of local inflammation. Macrophage infiltration was observed. MiR-27a and cytokines levels in serum and adipose tissue were measured. Macrophage polarization markers and protein expression in insulin or inflammatory signaling pathways were observed. Impaired glucose tolerance and insulin tolerance was observed in 4w, 8w and 12w of high fat diet and miR-27a overexpression mice. Concurrently, miR-27a was increased in serum in a time-dependent manner, along with M1 cytokines and M1 macrophages increasing in adipose tissue clearly. Insulin signaling pathway was blocked, and PPARγ was suppressed. However, NF-κB was activated. On the other hand, activated macrophages and hypertrophic adipocytes induced by miR-27a could increase the ratio of Raw264.7 migration, including improving cytokines generation, and blocking PPARγ expression markedly. The present studies are conducted to clarify that miR-27a has increased along with up-regulation in the process of proinflammatory cytokines generation, macrophage influx and M1 macrophage polarization in obesity. These indicate that miR-27a gives the novel target of intervention for inflammation and insulin resistance in obesity.