Luteolin-Enriched Artichoke Leaf Extract Alleviates the Metabolic Syndrome in Mice with High-Fat Diet-Induced Obesity

Luteolin alleviates muscle atrophy, mitochondrial dysfunction and abnormal FNDC5 expression in high fat diet-induced obese rats and palmitic acid-treated C2C12 myotubes

Obesity is associated with a series of skeletal muscle impairments and dysfunctions, which are characterized by metabolic disturbances and muscle atrophy. Luteolin is a phenolic phytochemical with broad pharmacological activities. The present study aimed to evaluate the protective effects of Luteolin on muscle function and explore the potential mechanisms in high-fat diet (HFD)-induced obese rats and palmitic acid (PA)-treated C2C12 myotubes. Male Sprague-Dawley (SD) rats were fed with a control diet or HFD and orally administrated 0.5% sodium carboxymethyl cellulose (vehicle) or Luteolin (25, 50 and 100 mg/kg, respectively) for 12 weeks. The results showed that Luteolin ameliorated HFD-induced body weight gain, glucose intolerance and hyperlipidemia. Luteolin also alleviated muscle atrophy, decreased ectopic lipid deposition and prompted muscle-fiber-type conversion in the skeletal muscle. Meanwhile, we observed an evident improvement in mitochondrial quality control and respiratory capacity, accompanied by reduced oxidative stress. Mechanistic studies indicated that AMPK/SIRT1/PGC-1α signaling pathway plays a key role in the protective effects of Luteolin on skeletal muscle in the obese states, which was further verified by using specific inhibitors of AMPK and SIRT1. Moreover, the mRNA expression levels of markers in brown adipocyte formation were significantly up-regulated post Luteolin supplementation in different adipose depots. Taken together, these results revealed that Luteolin supplementation might be a promising strategy to prevent obesity-induced loss of mass and biological dysfunctions of skeletal muscle.

Luteolin: A promising multifunctional natural flavonoid for human diseases

Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/β-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.

An Overview of the Versatility of the Parts of the Globe Artichoke (Cynara scolymus L.), Its By-Products and Dietary Supplements

Cynara scolymus, also known as the globe artichoke or artichoke, is grown as a food, mainly in the Mediterranean, Canary Islands, and Egypt, as well as in Asia and South America. It has also been associated with various health benefits and is used in plant-based dietary supplements and herbal infusions. Its edible parts, consisting of the head or capitula, flower, and leaves, have shown various biological activities, including anti-cancer, hepatoprotective and antimicrobial potential. The leaves are mainly used in infusions and extracts for their health-promoting properties, although all their edible parts may also be consumed as fresh, frozen, or canned foods. However, its primary health-promoting activity is associated with its antioxidant potential, which has been linked to its chemical composition, particularly its phenolic compounds (representing 96 mg of gallic acid equivalent per 100 g of raw plant material) and dietary fiber. The main phenolic compounds in the heads and leaves are caffeic acid derivatives, while the flavonoids luteolin and apigenin (both present as glucosides and rutinosides) have also been identified. In addition, heat-treated artichokes (i.e., boiled, steamed or fried), their extracts, and waste from artichoke processing also have antioxidant activity. The present paper reviews the current literature concerning the biological properties of different parts of C. scolymus, its by-products and dietary supplements, as well as their chemical content and toxicity. The literature was obtained by a search of PubMed/Medline, Google Scholar, Web of Knowledge, ScienceDirect, and Scopus, with extra papers being identified by manually reviewing the references.

B. longum CKD1 enhances the efficacy of anti-diabetic medicines through upregulation of IL- 22 response in type 2 diabetic mice

The gut microbiota plays a pivotal role in metabolic disorders, notably type 2 diabetes mellitus (T2DM). In this study, we investigated the synergistic potential of combining the effects of Bifidobacterium longum NBM7-1 (CKD1) with anti-diabetic medicines, LobeglitazoneⓇ (LO), SitagliptinⓇ (SI), and MetforminⓇ (Met), to alleviate hyperglycemia in a diabetic mouse model. CKD1 effectively mitigated insulin resistance, hepatic steatosis, and enhanced pancreatic β-cell function, as well as fortifying gut-tight junction integrity. In the same way, SI-CKD1 and Met- CKD1 synergistically improved insulin sensitivity and prevented hepatic steatosis, as evidenced by the modulation of key genes associated with insulin signaling, β-oxidation, gluconeogenesis, adipogenesis, and inflammation by qRT-PCR. The comprehensive impact on modulating gut microbiota composition was observed, particularly when combined with MetforminⓇ. This combination induced an increase in the abundance of Rikenellaceae and Alistipes related negatively to the T2DM incidence while reducing the causative species of Cryptosporangium, Staphylococcaceae, and Muribaculaceae. These alterations intervene in gut microbiota metabolites to modulate the level of butyrate, indole-3-acetic acid, propionate, and inflammatory cytokines and to activate the IL-22 pathway. However, it is meaningful that the combination of B. longum NBM7-1(CKD1) reduced the medicines' dose to the level of the maximal inhibitory concentrations (IC50). This study advances our understanding of the intricate relationship between gut microbiota and metabolic disorders. We expect this study to contribute to developing a prospective therapeutic strategy modulating the gut microbiota.

The Effect of an Innovative Combination of Bergamot Polyphenolic Fraction and Cynara cardunculus L. Extract on Weight Gain Reduction and Fat Browning in Obese Mice

Obesity is one of the world's most serious public health issues, with a high risk of developing a wide range of diseases. As a result, focusing on adipose tissue dysfunction may help to prevent the metabolic disturbances commonly associated with obesity. Nutraceutical supplementation may be a crucial strategy for improving WAT inflammation and obesity and accelerating the browning process. The aim of this study was to perform a preclinical "proof of concept" study on Bergacyn®, an innovative formulation originating from a combination of bergamot polyphenolic fraction (BPF) and Cynara cardunculus (CyC), for the treatment of adipose tissue dysfunction. In particular, Bergacyn® supplementation in WD/SW-fed mice at doses of 50 mg/kg given orally for 12 weeks, was able to reduce body weight and total fat mass in the WD/SW mice, in association with an improvement in plasma biochemical parameters, including glycemia, total cholesterol, and LDL levels. In addition, a significant reduction in serum ALT levels was highlighted. The decreased WAT levels corresponded to an increased weight of BAT tissue, which was associated with a downregulation of PPARγ as compared to the vehicle group. Bergacyn® was able to restore PPARγ levels and prevent NF-kB overexpression in the WAT of mice fed a WD/SW diet, suggesting an improved oxidative metabolism and inflammatory status. These results were associated with a significant potentiation of the total antioxidant status in WD/SW mice. Finally, our data show, for the first time, that Bergacyn® supplementation may be a valuable approach to counteract adipose tissue dysfunction and obesity-associated effects on cardiometabolic risk.

Mechanisms of action of natural products on type 2 diabetes

Over the past several decades, type 2 diabetes mellitus (T2DM) has been considered a global public health concern. Currently, various therapeutic modalities are available for T2DM management, including dietary modifications, moderate exercise, and use of hypoglycemic agents and lipid-lowering medications. Although the curative effect of most drugs on T2DM is significant, they also exert some adverse side effects. Biologically active substances found in natural medicines are important for T2DM treatment. Several recent studies have reported that active ingredients derived from traditional medicines or foods exert a therapeutic effect on T2DM. This review compiled important articles regarding the therapeutic effects of natural products and their active ingredients on islet β cell function, adipose tissue inflammation, and insulin resistance. Additionally, this review provided an in-depth understanding of the multiple regulatory effects on different targets and signaling pathways of natural medicines in the treatment of T2DM as well as a theoretical basis for clinical effective application.

Evaluation of the Protective and Regenerative Properties of Commercially Available Artichoke Leaf Powder Extract on Plasma and Liver Oxidative Stress Parameters

Hepatocellular damage by the harmful effects of xenobiotics, which increase the production of free radicals, is a widespread phenomenon. The extract from the leaves of Cynara scolymus L. available as an artichoke preparation (natural source) of antioxidants may serve as a potential hepatoprotective factor. This study aimed to evaluate the impact of the protective and regenerative properties of artichoke preparation on the liver in three extract doses: 0.5; 1.0; and 1.5 g/kg bw/day. The evaluation was conducted by measuring the levels of oxidative stress parameters, including glutathione (GSH), glutathione S-transferases (GST), nitric oxide (NO), superoxide dismutase (SOD), catalase (CAT), Trolox equivalent antioxidant capacity (TEAC), thiobarbituric acid reactive substances (TBARS), glutathione peroxidase (GPx), paraoxonase 1 (PON1), SH- group, nitrosylated protein (RSNO), as well as such liver enzymes as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in the plasma and liver homogenate of rats with liver damage induced by CCl4 (1 mL/kg bw). Measurements were taken in plasma and liver homogenate. The results have demonstrated that the artichoke preparation, owing to its high antioxidative potential, exhibits protective and regenerative effects on the liver. This is supported by the observation of higher GSH levels in the plasma of rats treated with artichoke extract for two weeks before CCl4 exposure. Furthermore, the artichoke extract has shown regenerative properties, as evidenced by lower ALT, AST, and SOD activity in the group treated with artichoke extract after CCl4 exposure. These findings suggest that the in vivo administration of artichoke preparation may be beneficial for the protection and regeneration of the liver.

The potential role of alfalfa polysaccharides and their sulphated derivatives in the alleviation of obesity

Sulfated alfalfa polysaccharides (SAPs) as derivatives of alfalfa polysaccharides (APs) showed better in vitro antioxidant activity and potential obesity inhibition. The purpose of this study was to investigate the effect and mechanisms of APs and SAPs on obesity alleviation. Different concentrations of APs and SAPs were tested for effects on body conditions, gut flora, antioxidant capacity, and immunological factors. The results showed that APs and SAPs improved the physical conditions of obese mice, including organ weight, body weight, intraperitoneal fat ratio, and lipid levels. APs and SAPs increased the antioxidant capacity of the obese mice, enhanced the activity of SOD and CAT, and decreased the activity of MDA in the serum, liver, and colon. APs and SAPs upregulated the mRNA expression of IL-4 and IL-10 and downregulated the mRNA expression of NF-κB, IFN-γ, TNF-α, and IL-6 in the liver and colon. Meanwhile, APs and SAPs improved lipid absorption in the jejunum, upregulated LXR and GLP-2, and down-regulated the mRNA expression of NPC1L1. APs and SAPs also contributed to restoring short-chain fatty acid levels in the colon. APs and SAPs improved the structure of the intestinal flora, promoted the proliferation of bacteria associated with short-chain fatty acid metabolism, and inhibited the proliferation of pathogenic bacteria. At the same concentration, the effect of SAPs on the antioxidant capacity was stronger than that of APs. In the AP group, high concentrations of APs showed the best anti-inflammatory effect, while in the SAP group, medium concentrations of SAPs showed the best inhibition of inflammation. Our results suggest that APs and SAPs alleviate obesity symptoms by relieving inflammation, improving the antioxidant capacity, and regulating intestinal flora and therefore could be used as potential probiotic products to alleviate obesity.

Chronic Excessive Fructose Intake Maximizes Brown Adipocyte Whitening but Causes Similar White Adipocyte Hypertrophy Than a High-Fat Diet in C57BL/6 Mice

Objective: This study aimed to evaluate the differential role of a high-fat diet (HF) or high-fructose diet (HFRU) on white adipose tissue and brown adipose tissue remodeling in C57BL/6 mice.Methods: The animals were randomly assigned to receive HF (50% of energy as lipids), HFRU (50% of energy as fructose), or a control diet (C, 10% of energy as lipids) for 12 weeks. Results: The HF group became overweight from the 7th week onwards, but both HF and HFRU groups showed hyperinsulinemia, oral glucose intolerance, and adverse adipose tissue remodeling. HF and HFRU groups showed interscapular brown adipose tissue whitening, tough the reduced Q_A [nuclei] suggested maximized brown adipocyte dysfunction due to the HFRU diet. In contrast, HF and HFRU diets exerted similar effects upon subcutaneous white adipocytes, with a similar average cross-sectional area. Immunohistochemistry confirmed the whitening enhancement with reduced UCP1 immunodensity in the HFRU group. Conclusion: In conclusion, HF and HFRU diets had indistinguishable effects upon white adipocyte morphology, but the HFRU diet provoked a more pronounced whitening than the HF diet after a 12-week protocol. These results point to the silent and harmful impact that excessive fructose has upon the metabolism of lean mice.

Circulating Human Metabolites Resulting from TOTUM-070 Absorption (a Plant-Based, Polyphenol-Rich Ingredient) Improve Lipid Metabolism in Human Hepatocytes: Lessons from an Original Ex Vivo Clinical Trial

TOTUM-070 is a patented polyphenol-rich blend of five different plant extracts showing separately a latent effect on lipid metabolism and potential synergistic properties. In this study, we investigated the health benefit of such a formula. Using a preclinical model of high fat diet, TOTUM-070 (3 g/kg of body weight) limited the HFD-induced hyperlipemia with a reduction in triglyceride (-32% after 6 weeks; -20.3% after 12 weeks) and non-HDL cholesterol levels (-21% after 6 weeks; -38.4% after 12 weeks). To further investigate such a benefit and its underlying mechanisms in humans, we designed an ex vivo clinical approach to collect the circulating bioactives resulting from TOTUM-070 ingestion and to determine their biological activities on human hepatocytes. Human serum was obtained from healthy subjects before and after intake of TOTUM-070 (4995 mg). The presence of circulating metabolites was assessed by UPLC-MS/MS. Serum containing metabolites was further incubated with hepatocytes cultured in a lipotoxic environment (palmitate, 250 µM). RNA sequencing analyses show that lipid metabolism was one of the most impacted processes. Using histologic, proteomic, and enzymatic assays, the effects of human TOTUM-070 bioactives on hepatocyte metabolism were characterized by (1) the inhibition of lipid storage, including both (2) triglycerides (-41%, p < 0.001) and (3) cholesterol (-50%, p < 0.001) intracellular content, (4) a reduced de novo cholesterol synthesis (HMG-CoA reductase activity -44%, p < 0.001), and (5) a lowered fatty acid synthase protein level (p < 0.001). Altogether, these data support the beneficial impact of TOTUM-070 on lipid metabolism and provide new biochemical insights in human mechanisms occurring in liver cells.

Natural Compounds with Aldose Reductase (AR) Inhibition: A Class of Medicative Agents for Fatty Liver Disease

Fatty liver disease (FLD), which includes both non-alcoholic fatty liver disease (NAFLD) and alcoholic fatty liver disease (ALD), is a worldwide health concern. The etiology of ALD is long-term alcohol consumption, while NAFLD is defined as an abnormal amount of lipid present in liver cells, which is not caused by alcohol intake and has recently been identified as a hepatic manifestation of metabolic syndrome (such as type 2 diabetes, obesity, hypertension, and obesity). Inflammation, oxidative stress, and lipid metabolic dysregulation are all known to play a role in FLD progression. Alternative and natural therapies are desperately needed to treat this disease since existing pharmaceuticals are mostly ineffective. The aldose reductase (AR)/polyol pathway has recently been shown to play a role in developing FLD by contributing to inflammation, oxidative stress, apoptosis, and fat accumulation. Herein, we review the effects of plantderived compounds capable of inhibiting AR in FLD models. Natural AR inhibitors have been found to improve FLD in part by suppressing inflammation, oxidative stress, and steatosis via the regulation of several critical pathways, including the peroxisome proliferator-activated receptor (PPAR) pathway, cytochrome P450 2E1 (CYP2E1) pathway, AMP-activated protein kinase (AMPK) pathway, etc. This review revealed that natural compounds with AR inhibitory effects are a promising class of therapeutic agents for FLD.

Natural Foods for the Treatment of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. The etiology of NAFLD is highly heterogeneous, which occurs and develops under the joint action of metabolism, inflammation, genetics, environment, and gut microbiota. At present, the principal therapeutic modalities targeting NAFLD are lifestyle interventions such as weight loss through diet and exercise. At present, there is no established therapy for the treatment of NAFLD, and many therapies are associated with a variety of side effects. A great number of in vitro and in vivo experiments have indicated that there are many natural foods that have therapeutic potential for NAFLD. This review summarizes the natural foods and their mechanisms that were found in recent years, furthermore, provides further information relevant to the treatment of NAFLD.

Luteolin ameliorates palmitate-induced lipotoxicity in hepatocytes by mediating endoplasmic reticulum stress and autophagy

Abnormal accumulation of lipids in liver leads to uncontrolled endoplasmic reticulum (ER) stress and autophagy. Luteolin is known to have antioxidant, anti-inflammatory, and anti-cancer properties, but whether it protects against lipotoxicity in liver remains unclear. In this study, we challenged AML12 liver cells and mouse primary hepatocytes with palmitic acid (PA) with or without luteolin pretreatment. In the presence of PA, reactive oxygen species (ROS) production was increased at 3 h, followed by enhancement of expression of p-PERK, ATF4, p-eIF2α, CHOP, and TXNIP (ER stress markers) and p-p62 and LC3II/LC3I ratio (autophagy markers), in both primary hepatocytes and AML12 cells. When PA treatment was extended up to 24 h, apoptosis was induced as evidenced by an increase in caspase-3 activation. RFP-GFP-LC3B transfection further revealed that the fusion of autophagosomes with lysosomes was damaged by PA. With luteolin treatment, the expression of antioxidant enzymes, i.e., heme oxygenase-1 and glutathione peroxidase, was upregulated, and PA-induced ROS production, ER stress, and cell death were dose-dependently ameliorated. Luteolin could also reverse the damage caused to autophagic flux. These results indicate that luteolin protects hepatocytes against PA assault by enhancing antioxidant defense, which can attenuate ER stress and autophagy as well as promote autophagic flux.

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.

Recent Updates on Source, Biosynthesis, and Therapeutic Potential of Natural Flavonoid Luteolin: A Review

Nature gives immense resources that are beneficial to humankind. The natural compounds present in plants provide primary nutritional values to our diet. Apart from food, plants also provide chemical compounds with therapeutic values. The importance of these plant secondary metabolites is increasing due to more studies revealing their beneficial properties in treating and managing various diseases and their symptoms. Among them, flavonoids are crucial secondary metabolite compounds present in most plants. Of the reported 8000 flavonoid compounds, luteolin is an essential dietary compound. This review discusses the source of the essential flavonoid luteolin in various plants and its biosynthesis. Furthermore, the potential health benefits of luteolins such as anti-cancer, anti-microbial, anti-inflammatory, antioxidant, and anti-diabetic effects and their mechanisms are discussed in detail. The activity of luteolin and its derivatives are diverse, as they help to prevent and control many diseases and their life-threatening effects. This review will enhance the knowledge and recent findings regarding luteolin and its therapeutic effects, which are certainly useful in potentially utilizing this natural metabolite.

Nutritional activities of luteolin in obesity and associated metabolic diseases: an eye on adipose tissues

Obesity is characterized by excessive body fat accumulation and is a high-risk factor for metabolic comorbidities, including type 2 diabetes, nonalcoholic fatty liver disease, and cardiovascular disease. In lean individuals, adipose tissue (AT) is not only an important regulatory organ for energy storage and metabolism, but also an indispensable immune and endocrine organ. The sustained energy imbalance induces adipocyte hypotrophy and hyperplasia as well as AT remodeling, accompanied by chronic low-grade inflammation and adipocytes dysfunction in AT, ultimately leading to systemic insulin resistance and ectopic lipid deposition. Luteolin is a natural flavonoid widely distributed in fruits and vegetables and possesses multifold biological activities, such as antioxidant, anticancer, and anti-inflammatory activities. Diet supplementation of this flavonoid has been reported to inhibit AT lipogenesis and inflammation as well as the ectopic lipid deposition, increase AT thermogenesis and systemic energy expenditure, and finally improve obesity and associated metabolic diseases. The purpose of this review is to reveal the nutritional activities of luteolin in obesity and its complications with emphasis on its action on AT energy metabolism, immunoregulation, and endocrine intervention.

Bioactive Compounds from Cardoon as Health Promoters in Metabolic Disorders

Cardoon (Cynara cardunculus L.) is a Mediterranean plant and member of the Asteraceae family that includes three botanical taxa, the wild perennial cardoon (C. cardunculus L. var. sylvestris (Lamk) Fiori), globe artichoke (C. cardunculus L. var. scolymus L. Fiori), and domesticated cardoon (C. cardunculus L. var. altilis DC.). Cardoon has been widely used in the Mediterranean diet and folk medicine since ancient times. Today, cardoon is recognized as a plant with great industrial potential and is considered as a functional food, with important nutritional value, being an interesting source of bioactive compounds, such as phenolics, minerals, inulin, fiber, and sesquiterpene lactones. These bioactive compounds have been vastly described in the literature, exhibiting a wide range of beneficial effects, such as antimicrobial, anti-inflammatory, anticancer, antioxidant, lipid-lowering, cytotoxic, antidiabetic, antihemorrhoidal, cardiotonic, and choleretic activity. In this review, an overview of the cardoon nutritional and phytochemical composition, as well as its biological potential, is provided, highlighting the main therapeutic effects of the different parts of the cardoon plant on metabolic disorders, specifically associated with hepatoprotective, hypolipidemic, and antidiabetic activity.

Paving Luteolin Therapeutic Potentialities and Agro-Food-Pharma Applications: Emphasis on In Vivo Pharmacological Effects and Bioavailability Traits

Luteolin is a naturally occurring secondary metabolite belonging to the class of flavones. As many other natural flavonoids, it is often found in combination with glycosides in many fruits, vegetables, and plants, contributing to their biological and pharmacological value. Many preclinical studies report that luteolin present excellent antioxidant, anticancer, antimicrobial, neuroprotective, cardioprotective, antiviral, and anti-inflammatory effects, and as a consequence, various clinical trials have been designed to investigate the therapeutic potential of luteolin in humans. However, luteolin has a very limited bioavailability, which consequently affects its biological properties and efficacy. Several drug delivery strategies have been developed to raise its bioavailability, with nanoformulations and lipid carriers, such as liposomes, being the most intensively explored. Pharmacological potential of luteolin in various disorders has also been underlined, but to some of them, the exact mechanism is still poorly understood. Given the great potential of this natural antioxidant in health, this review is aimed at providing an extensive overview on the in vivo pharmacological action of luteolin and at stressing the main features related to its bioavailability, absorption, and metabolism, while essential steps determine its absolute health benefits and safety profiles. In addition, despite the scarcity of studies on luteolin bioavailability, the different drug delivery formulations developed to increase its bioavailability are also listed here.

Artichoke leaf extract supplementation lowers hepatic oxidative stress and inflammation and increases multidrug resistance-associated protein 2 in mice fed a high-fat and high-cholesterol diet

Artichoke (Cynara scolymus) leaf extract (ALE) contains many phytonutrients that may have antioxidant and anti-inflammation activities against many diseases including liver damage. To investigate the protective effects of ALE on high-fat and high-cholesterol (HFHC) diet-induced steatohepatitis and liver damage in mice, twenty-four female mice were fed an HFHC diet without or with 0.5% and 1% ALE supplementation for 6 weeks. The antioxidant and anti-inflammation activities and histological changes in the liver after ALE treatment were evaluated. The results show that ALE treatment reduced the HFHC diet-induced elevation of liver damage, as indicated by an increased alanine aminotransferase activity in plasma and perivenular inflammatory infiltrates in the liver. In addition, ALE ameliorated HFHC diet-induced depletion of hepatic glutathione (GSH) and elevations of plasma total cholesterol, triglyceride and hepatic triglyceride. ALE suppressed HFHC diet-induced accumulation of cholesterol precursors, including squalene and desmosterol in the liver. Higher hepatic GSH contents and activities of GSH-related enzymes were observed after ALE treatment. Higher expressions of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 (HO-1) were induced by the HFHC diet; however, ALE treatment reduced HO-1 expression. The NOD-like receptor protein 3, caspase-1, and interleukin-1β protein and mRNA levels were reduced in the liver by ALE. A higher multidrug resistance-associated protein 2 expression in the liver was found after ALE treatment. These results suggest that ALE may ameliorate oxidative stress, inflammation and lipid metabolism disorder in HFHC diet-induced steatohepatitis and liver damage.

Metabolic and Anti-Inflammatory Protective Properties of Human Enriched Serum Following Artichoke Leaf Extract Absorption: Results from an Innovative Ex Vivo Clinical Trial

The aging of our population is accompanied by an increased prevalence of chronic diseases. Among those, liver, joint and adipose tissue-related pathologies have a major socio-economic impact. They share common origins as they result from a dysregulation of the inflammatory and metabolic status. Plant-derived nutrients and especially polyphenols, exert a large range of beneficial effects in the prevention of chronic diseases but require clinically validated approaches for optimized care management. In this study, we designed an innovative clinical approach considering the metabolites produced by the digestive tract following the ingestion of an artichoke leaf extract. Human serum, enriched with metabolites deriving from the extract, was collected and incubated with human hepatocytes, human primary chondrocytes and adipocytes to determine the biological activity of the extract. Changes in cellular behavior demonstrated that the artichoke leaf extract protects hepatocytes from lipotoxic stress, prevents adipocytes differentiation and hyperplasia, and exerts chondroprotective properties in an inflammatory context. These data validate the beneficial health properties of an artichoke leaf extract at the clinical level and provide both insights and further evidence that plant-derived nutrients and especially polyphenols from artichoke may represent a relevant alternative for nutritional strategies addressing chronic disease issues.

Lupin protein isolate improves insulin sensitivity and steatohepatitis in vivo and modulates the expression of the Fasn, Gys2, and Gsk3b genes

Although studies on lupin protein isolate (LPI) have indicated the presence of a preventive effect on insulin resistance (IR) and lipid disturbances, their influence on established pathological traits has received little attention. Here, we evaluated the in vivo effects of LPI on IR and steatohepatitis as well as its influence on genes involved in lipid and carbohydrate metabolism. We first induced IR and steatohepatitis in rats by maintaining them on a high-fat diet for 5 weeks. Thereafter, we administered LPI to the rats daily for 3 weeks. LPI improved insulin sensitivity (AUC: 6,777 ± 232 vs. 4,971 ± 379, p < .05, pre- vs. post-treatment values) and reduced glucose and triglyceride levels by one-third. In addition, LPI-treated rats exhibited attenuated steatohepatitis. At the molecular level, LPI treatment reduced liver Fasn gene expression substantially but increased Gys2 and Gsk3b levels. We concluded that the hypolipidemic and hypoglycemic activities of LPI may be caused by reduced liver lipogenesis and modulation of insulin sensitization mechanisms.

Dietary Luteolin: A Narrative Review Focusing on Its Pharmacokinetic Properties and Effects on Glycolipid Metabolism

Luteolin, a flavone subclass of flavonoids, is commonly found in food plants and has multiple biological activities. Recently, evidence is growing with regard to the potential of luteolin intake to beneficially affect glycolipid metabolism disorders (GLMDs), particularly insulin resistance, diabetes, and obesity. The aim of this contribution is to provide an overview of recent advances in identifying and understanding the pharmacokinetic properties (absorption, metabolism, and bioavailability) of luteolin, its regulatory effects on glycolipid metabolism, and the underlying mechanisms of action of luteolin in the brain, liver, adipose tissues, and other tissues/organs. Collectively, luteolin or its principal metabolites may contribute to counteracting GLMDs, especially for human obesity and diabetes.

Herbal therapy as a promising approach for regulation on lipid profiles: A review of molecular aspects

Impaired lipid profile is defined as abnormal plasma levels of low-density lipoprotein, triglycerides, and total cholesterol. This disease state is associated with the development and progression of various disorders, such as diabetes mellitus, cardiovascular diseases, and acute myocardial infarction. Globally, all of these disorders are related to a significant rate of death. Therefore, finding a suitable approach for the prevention and treatment of lipid profile-related disorders is in the spotlight. Recently, herbal therapy has been considered a promising therapeutic approach for the treatment of hyperlipidemia or its related disorders due to its safety and efficacy. Hereby, we address the potential benefits of some of these herbal compounds on different aspects of lipid profile and its abnormalities with a special focus on their underlying mechanisms. Using herbal products, such as teas and mushrooms, or their derivatives, Rosmarinus officinalis Linn, Curcuma longa, Green tea, Lippia triphylla, Lippia citriodora, Plantago asiatica L, Vine tea, and Grifola frondosa have been proved to exert several therapeutic impacts on lipid profile and its related disorders, and we would provide a brief review on them in this literature.

The effects of supplementation with Cynara scolymus L. on anthropometric indices: А systematic review and dose-response meta-analysis of clinical trials

BACKGROUND

Studies on the efficacy of artichoke administration on anthropometric indices gave different outcomes. Hence, a systematic review and dose-response meta-analysis were accomplished to understand the effects of artichoke administration on anthropometric indices.

METHODS

Related clinical trials were found by searching in PubMed, Embase, the Cochrane Library and Scopus databases up to 29 February 2020. Weighted Mean Differences (WMD) were analyzed using a random-effects model. Heterogeneity, publication bias and sensitivity analysis were assessed for anthropometric indices.

RESULTS

Pooled analysis of 10 randomized controlled trials (RCTs) suggested that the artichoke administration has effect on waist circumference (WMD: -1.11 cm, 95 % CI: -2.08 to - 0.14), as opposed to the other anthropometric indices including weight (WMD: -0.62 kg, 95 % CI: -1.86 to 0.61) or BMI (WMD: -0.12, 95 % CI: -0.43 to 0.20). However, the analysis of the subgroups according to the health status showed that artichoke supplementation in hypertensive patients significantly reduced weight (WMD: -2.34 kg, 95 % CI: -3.11 to -1.57) but not the other indicators (WMD: -0.06 kg, 95 % CI: 0.78 to 0.67).

CONCLUSIONS

The artichoke supplementation has effect on the waist circumference, but not on the other anthropometric indices. For establishment of more accurate conclusion more studies with longer administration duration are need to be done.

Exploring the protective effect of Modified Xiaochaihu Decoction against hepatic steatosis and inflammation by network pharmacology and validation in ageing rats

Background

Based on therapy with syndrome differentiation and clinical studies on Xiaochaihu decoction (XCHD), we hypothesize that Modified Xiaochaihu Decoction (MXD) has an ability to ameliorate non-alcoholic fatty liver disease (NAFLD). This study aims to elucidate the pharmacological efficacy of MXD and its mechanism in the treatment of NAFLD by network pharmacology and experimental validation.

Methods

The active ingredients in MXD and their potential targets were identified using network analysis followed by experimental validation. First, we used data on the ingredients and targets obtained from professional database and related literature to do PPI network analysis, GO functional analysis, and KEGG pathway enrichment analysis. Core targets identified by network pharmacology were then tested in natural ageing female rats model. Indexes of lipid and glucose homeostasis were determined enzymatically and/or histologically. Gene expression was analyzed by real-time PCR and/or Western blot (WB).

Results

In total, 4009 NAFLD-related targets and 1953 chemical ingredients of MXD were obtained. In-depth network analysis of 140 common targets indicated that MXD played a critical role in anti-NAFLD via multiple targets and pathways. Based on the data of PPI analysis, GO functional enrichment analysis, KEGG pathway enrichment analysis, and literatures on the mechanism of NAFLD, we chose the core targets related to lipid metabolism (SREBP-1c, ChREBP, FASN, PPARα, and ACACA) and inflammation (IL-6 and NF-κB) to do further study. Significantly, in further animal verification experiment we using naturally ageing rats with NAFLD as a model, we found that MXD administration ameliorated age-related NAFLD and mechanistically down-regulated the mRNA/protein expression of core targets in lipid metabolism and inflammation related pathways such as FASN, ACACA, IL-6, and NF-κB. In addition, 12 of 24 potential ingredients acting on verified targets came from BC, and 11 of 24 potential ingredients acting on verified targets were derived from SM, implying that both BC and SM served as the key role in MXD against NAFLD.

Conclusion

The bioinformatics data and in vivo experimental results suggest that the MXD-induced amelioration of NAFLD may be predominantly related to modulation of lipid metabolism and inflammation. Both BC and SM serve as the key role in MXD against NAFLD. These results may provide novel evidence for clinical implication of MXD.

Metabolic Impact of Flavonoids Consumption in Obesity: From Central to Peripheral

The prevention and treatment of obesity is primary based on the follow-up of a healthy lifestyle, which includes a healthy diet with an important presence of bioactive compounds such as polyphenols. For many years, the health benefits of polyphenols have been attributed to their anti-oxidant capacity as free radical scavengers. More recently it has been described that polyphenols activate other cell-signaling pathways that are not related to ROS production but rather involved in metabolic regulation. In this review, we have summarized the current knowledge in this field by focusing on the metabolic effects of flavonoids. Flavonoids are widely distributed in the plant kingdom where they are used for growing and defensing. They are structurally characterized by two benzene rings and a heterocyclic pyrone ring and based on the oxidation and saturation status of the heterocyclic ring flavonoids are grouped in seven different subclasses. The present work is focused on describing the molecular mechanisms underlying the metabolic impact of flavonoids in obesity and obesity-related diseases. We described the effects of each group of flavonoids in liver, white and brown adipose tissue and central nervous system and the metabolic and signaling pathways involved on them.

The Targeted Impact of Flavones on Obesity-Induced Inflammation and the Potential Synergistic Role in Cancer and the Gut Microbiota

Obesity is an inflammatory disease that is approaching pandemic levels, affecting nearly 30% of the world's total population. Obesity increases the risk of diabetes, cardiovascular disorders, and cancer, consequentially impacting the quality of life and imposing a serious socioeconomic burden. Hence, reducing obesity and related life-threatening conditions has become a paramount health challenge. The chronic systemic inflammation characteristic of obesity promotes adipose tissue remodeling and metabolic changes. Macrophages, the major culprits in obesity-induced inflammation, contribute to sustaining a dysregulated immune function, which creates a vicious adipocyte-macrophage crosstalk, leading to insulin resistance and metabolic disorders. Therefore, targeting regulatory inflammatory pathways has attracted great attention to overcome obesity and its related conditions. However, the lack of clinical efficacy and the undesirable side-effects of available therapeutic options for obesity provide compelling reasons for the need to identify additional approaches for the prevention and treatment of obesity-induced inflammation. Plant-based active metabolites or nutraceuticals and diets with an increased content of these compounds are emerging as subjects of intense scientific investigation, due to their ability to ameliorate inflammatory conditions and offer safe and cost-effective opportunities to improve health. Flavones are a class of flavonoids with anti-obesogenic, anti-inflammatory and anti-carcinogenic properties. Preclinical studies have laid foundations by establishing the potential role of flavones in suppressing adipogenesis, inducing browning, modulating immune responses in the adipose tissues, and hindering obesity-induced inflammation. Nonetheless, the understanding of the molecular mechanisms responsible for the anti-obesogenic activity of flavones remains scarce and requires further investigations. This review recapitulates the molecular aspects of obesity-induced inflammation and the crosstalk between adipocytes and macrophages, while focusing on the current evidence on the health benefits of flavones against obesity and chronic inflammation, which has been positively correlated with an enhanced cancer incidence. We conclude the review by highlighting the areas of research warranting a deeper investigation, with an emphasis on flavones and their potential impact on the crosstalk between adipocytes, the immune system, the gut microbiome, and their role in the regulation of obesity.

The Protective Effect of Cynara Cardunculus Extract in Diet-Induced NAFLD: Involvement of OCTN1 and OCTN2 Transporter Subfamily

Hyperlipidemia and insulin-resistance are often associated with Non-Alcoholic Fatty Liver Disease (NAFLD) thereby representing a true issue worldwide due to increased risk of developing cardiovascular and systemic disorders. Although clear evidence suggests that circulating fatty acids contribute to pathophysiological mechanisms underlying NAFLD and hyperlipidemia, further studies are required to better identify potential beneficial approaches for counteracting such a disease. Recently, several artichoke extracts have been used for both reducing hyperlipidemia, insulin-resistance and NAFLD, though the mechanism is unclear. Here we used a wild type of Cynara Cardunculus extract (CyC), rich in sesquiterpens and antioxidant active ingredients, in rats fed a High Fat Diet (HFD) compared to a Normal Fat Diet (NFD). In particular, in rats fed HFD for four consecutive weeks, we found a significant increase of serum cholesterol, triglyceride and serum glucose. This effect was accompanied by increased body weight and by histopathological features of liver steatosis. The alterations of metabolic parameters found in HFDs were antagonised dose-dependently by daily oral supplementation of rats with CyC 10 and 20 mg/kg over four weeks, an effect associated to significant improvement of liver steatosis. The effect of CyC (20 mg/kg) was also associated to enhanced expression of both OCTN1 and OCTN2 carnitine-linked transporters. Thus, present data suggest a contribution of carnitine system in the protective effect of CyC in diet-induced hyperlipidemia, insulin-resistance and NAFLD.

Effect of Luteolin and Apigenin on the Production of Il-31 and Il-33 in Lipopolysaccharides-Activated Microglia Cells and Their Mechanism of Action

Microglia cells are resident cells of the central nervous system (CNS) charged with modulating inflammation in the CNS. Overstimulation of microglia cells continuously releases inflammatory mediators that contribute to neurodegenerative diseases. Apigenin and Luteolin are flavonoids with reported anti-inflammatory activities. However, their effects on IL-31 and IL-33 production in microglial cells are unknown. Here, we investigated the effects of apigenin and luteolin on the production of IL-31 and IL-33 by microglia cells. SIM-A9 microglial cells were pre-treated with apigenin or luteolin and stimulated with lipopolysaccharides to evaluate the production of IL-31 and IL-33. The study revealed that apigenin and luteolin inhibited the production of IL-31 and IL-33 at the gene and protein expressions and the secretion levels. Using potent inhibitors of MAPK, NF-κB, and STAT3 signaling pathways, we demonstrated that apigenin and luteolin’s suppression of ERK and JNK contributed to the inhibition of IL-31 and IL-33 in the MAPK pathway. Luteolin’s suppression of NF-κB and STAT3 also contributed to the inhibition of IL-31 and IL-33. Further analysis revealed that both compounds prevented nuclear translocation of activated NF-κB and STAT3, an act that subsequently prevented their DNA binding activities. Collectively, the study suggested that apigenin and luteolin’s regulation of signaling pathways contributed to the inhibition of IL-31 and IL-33, thus suggesting its importance for the improvement of neurodegenerative diseases involving these two cytokines.

Reduction of blood glucose by plant extracts and their use in the treatment of diabetes mellitus; discrepancies in effectiveness between animal and human studies

ETHNOPHARMACOLOGICAL RELEVANCE

The global problem of diabetes, together with the limited access of large numbers of patients to conventional antidiabetic medicines, continues to drive the search for new agents. Ancient Asian systems such as traditional Chinese medicine, Japanese Kampo medicine, and Indian Ayurvedic medicine, as well as African traditional medicine and many others have identified numerous plants reported anecdotally to treat diabetes; there are probably more than 800 such plants for which there is scientific evidence for their activity, mostly from studies using various models of diabetes in experimental animals.

AIM OF THE REVIEW

Rather than a comprehensive coverage of the literature, this article aims to identify discrepancies between findings in animal and human studies, and to highlight some of the problems in developing plant extract-based medicines that lower blood glucose in patients with diabetes, as well as to suggest potential ways forward.

METHODS

In addition to searching the 2018 PubMed literature using the terms 'extract AND blood glucose, a search of the whole literature was conducted using the terms 'plant extracts' AND 'blood glucose' AND 'diabetes' AND 'double blind' with 'clinical trials' as a filter. A third search using PubMed and Medline was undertaken for systematic reviews and meta-analyses investigating the effects of plant extracts on blood glucose/glycosylated haemoglobin in patients with relevant metabolic pathologies.

FINDINGS

Despite numerous animal studies demonstrating the effects of plant extracts on blood glucose, few randomised, double-blind, placebo-controlled trials have been conducted to confirm efficacy in treating humans with diabetes; there have been only a small number of systematic reviews with meta-analyses of clinical studies. Qualitative and quantitative discrepancies between animal and human clinical studies in some cases were marked; the factors contributing to this included variations in the products among different studies, the doses used, differences between animal models and the human disease, and the impact of concomitant therapy in patients, as well as differences in the duration of treatment, and the fact that treatment in animals may begin before or very soon after the induction of diabetes.

CONCLUSION

The potential afforded by natural products has not yet been realised in the context of treating diabetes mellitus. A systematic, coordinated, international effort is required to achieve the goal of providing anti-diabetic treatments derived from medicinal plants.

The Effects of New Selective PPARα Agonist CP775146 on Systematic Lipid Metabolism in Obese Mice and Its Potential Mechanism

PURPOSE

Peroxisome proliferator-activated receptor α (PPARα) plays a crucial role in the control of lipid homeostasis. Here, we investigated the effects of CP775146, a new selective PPARα agonist, on lipid metabolism in diet-induced obese mice and its possible mechanism.

METHODS

C57BL/6 mice were fed a high-fat diet (HFD) for 12 weeks to induce obesity and then received CP775146 via intraperitoneal injection for 3 days. The content/morphology of the liver, serum lipid, and liver function was measured. The expression of genes related to lipolysis and synthesis in liver was detected by quantitative real-time PCR (qRT-PCR).

RESULTS

The safe dose of CP775146 was <0.3 mg/kg. CP775146 reduced the serum levels of liver enzymes, such as alanine aminotransferase (ALT) and glutamic-oxaloacetic transaminase (AST) and lipid metabolism-related biomarkers, including triglycerides (TGs) and low-density lipoprotein cholesterol (LDL-c), non-high-density lipoprotein cholesterol (non-HDL-c), and hepatic TG content, at a dosage of 0.1 mg/kg. HFD-induced pathological liver changes improved after CP775146 treatment. The expression of genes involved in liver fatty acid oxidation (acyl-coenzyme A dehydrogenase, long chain (Acadl), acyl-CoA oxidase 1 (Acox-1), carnitine palmitoyltransferase-1 (CPT-1), and enoyl-CoA, hydratase/3-hydroxyacyl CoA dehydrogenase (Ehhadh)) was upregulated in CP775146-treated mice. Furthermore, CP775146 induced the expression of thermogenesis genes (cell death-inducing DFFA-like effector a (Cidea), uncoupling protein 1 (Ucp1)) and lipolysis genes (hormone-sensitive lipase (Hsl), adipose tissue triglyceride lipase (Atgl)) in epididymal white adipose tissue (eWAT), activating browning and thermogenesis.

CONCLUSION

CP775146 efficiently alleviates obesity-induced liver damage, prevents lipid accumulation by activating the liver fatty acid β-oxidation pathway, and regulates the expression of genes that control brown fat-like pathway in eWAT.

Sicyos angulatus Prevents High-Fat Diet-Induced Obesity and Insulin Resistance in Mice

Obesity is a medical condition in which excess body fat has accumulated to a serious extent. It is a chronic disease that can lead to dyslipidemia, insulin resistance, and type 2 diabetes. In the present study, we investigated the anti-obesity effects of Sicyos angulatus (SA) extract on a high-fat diet (HFD)-induced C57BL/6J obese mice. The mice were divided into vehicle and three SA groups (25, 50, and 100 mg/kg body weight). The mice were fed a HFD with or without SA for 12 weeks. The oral administration of SA reduced body and adipose tissue weight in HFD-fed mice compared to those in the vehicle group (p<0.05). Adipocyte size and inflammation significantly decreased in the SA-administered groups in a dose-dependent manner. In particular, adipocytes larger than 5000 µm² were remarkably reduced by around 50% in the SA-treated groups (p<0.05). In addition, SA contributes towards reducing insulin resistance (measured as the HOMA-IR index) and glucose intolerance in HFD-induced obese mice (p<0.05; Vehicle 21.5±3.1 vs. SA100 4.7±0.4). These beneficial effects of SA on obesity may be linked to the suppression of lipogenesis and stimulating energy metabolism in white adipose tissue and muscle. In white adipose tissue and muscle, the administration of SA activated AMPK pathway, leading to the inhibition of the development of pathophysiological conditions associated with obesity, including lipogenesis and inflammation. These findings suggest that SA may prevent obesity through inhibiting fat accumulation in HFD-induced obese mice. Therefore, SA is able to exert metabolic benefits in the prevention of obesity and insulin resistance.

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.

Effect of Grifola frondosa 95% ethanol extract on lipid metabolism and gut microbiota composition in high-fat diet-fed rats

This study aimed to investigate the effects of 95% ethanol extract of G. frondosa (GF95) on lipid metabolism and gut microbiota composition in high-fat diet (HFD) fed rats.