1,2,3,4,6 penta-O-galloyl-β-D-glucose ameliorates high-fat diet-induced nonalcoholic fatty liver disease and maintains the expression of genes involved in lipid homeostasis in mice

A comprehensive review of medicinal Toxicodendron (Anacardiaceae): Botany, traditional uses, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Comprising of about 30 species, the genus Toxicodendron (Anacardiaceae) are mainly distributed in East Asia and North America. Among them, 13 species have been traditionally used as folk medicines in Asia and other parts of the world to treat blood diseases, abnormal bleeding, skin diseases, gastrointestinal diseases, liver diseases, bone injury, lung diseases, neurological diseases, cardiovascular diseases, tonic, cancer, eye diseases, menstrual irregularities, inflammation, rheumatism, diabetes mellitus, rattlesnake bite, internal parasites, contraceptive, vomiting and diarrhea.

AIM OF THE STUDY

To date, no comprehensive review on Toxicodendron has been published and the scientific basis of the traditional medicinal benefits of Toxicodendron have been less reported. Therefore, this review aims to provide a reference for further research and development on medicinal purpose of Toxicodendron by summarizing the works (from 1980 to 2023), and focusing on its botany, traditional uses, phytochemistry and pharmacology.

MATERIALS AND METHODS

The names of the species were from The Plant List Database (http://www.theplantlist.org), World Flora Online (http://www.worldfloraonline.org), Catalogue of Life Database (https://www.catalogueoflife.org/) and Plants for A Future Database (https://pfaf.org/user/Default.aspx). And the search terms "Toxicodendron" and "the names of 31 species and their synonyms" were used to search for information from electronic databases such as Web of Science, Scopus, Google Scholar, Science Direct, PubMed, Baidu Scholar, Springer, and Wiley Online Library. Moreover, PhD and MSc dissertations were also used to support this work.

RESULTS

These species on Toxicodendron are widely used in folkloric medicine and modern pharmacological activities. So far, approximately 238 compounds, mainly phenolic acids and their derivatives, urushiols, flavonoids and terpenoids, are extracted and isolated from Toxicodendron plants, commonly, T. trichocarpum, T. vernicifluum, T. succedaneum, and T. radicans. Among them, phenolic acids and flavonoids are the main compound classes that show pharmacological activities in Toxicodendron plants both in vitro and in vivo. Furthermore, the extracts and single compounds of these species show a wide range of activities, such as antioxidant, antibacterial, anti-inflammatory, anti-tumor, liver protection, fat reduction, nerve protection, and treatment of blood diseases.

CONCLUSIONS

Selected species of Toxicodendron have been used as herbal medicines in the Southeast Asian for a long time. Furthermore, some bioactive constituents have been identified from them, so plants in this genus may be potential new drugs. The existing research on Toxicodendron has been reviewed, and the phytochemistry and pharmacology provide theoretical basis for some of the traditional medicinal uses. Therefore, in this review, the traditional medicinal, phytochemical and modern pharmacology of Toxicodendron plants are summarized to help future researchers to find new drug leads or to get a better understanding of structure-activity relationships.

α-Lactalbumin Peptide Asp-Gln-Trp Ameliorates Hepatic Steatosis and Oxidative Stress in Free Fatty Acids-Treated HepG2 Cells and High-Fat Diet-Induced NAFLD Mice by Activating the PPARα Pathway

SCOPE

Dietary intervention has emerged as a promising strategy for the management of nonalcoholic fatty liver disease (NAFLD). The aim of this study is to investigate the ameliorative effects of the α-lactalbumin peptide Asp-Gln-Trp (DQW) against NAFLD and the underlying mechanism.

METHODS AND RESULTS

The models of lipid metabolism disorders are established both in HepG2 cells and in C57BL/6J mice. The results demonstrate that DQW activates peroxisome proliferator-activated receptor α (PPARα) and subsequently ameliorates lipid deposition and oxidative stress in vitro. Interestingly, GW6471 markedly attenuates the modulatory effects of DQW on the PPARα pathway in HepG2 cells. Moreover, results of in vivo experiments indicate that DQW alleviates body weight gain, dyslipidemia, hepatic steatosis, and oxidative stress in high-fat-diet (HFD)-induced NAFLD mice. At the molecular level, DQW activates PPARα, subsequently enhances fatty acid β-oxidation, and reduces lipogenesis, thereby ameliorating hepatic steatosis. Meanwhile, DQW may ameliorate liver injury and oxidative stress via activating the PPARα/nuclear-factor erythroid 2 (Nrf2)/heme-oxygenase 1 (HO-1) pathway.

CONCLUSION

Those results indicate that α-lactalbumin peptide DQW may be an effective dietary supplement for alleviating NAFLD by alleviating lipid deposition and oxidative stress.

Divya-WeightGo combined with moderate aerobic exercise remediates adiposopathy, insulin resistance, serum biomarkers, and hepatic lipid accumulation in high-fat diet-induced obese mice

Obesity has become an unprecedented epidemic worldwide owing to a prolonged imbalance between energy intake and expenditure. Available therapies primarily suppress energy intake but often fail to produce sustained fat loss, necessitating a more efficacious strategy to combat obesity. In this study, a polyherbal formulation, Divya-WeightGo (DWG) has been investigated for its anti-obesity activity using in-vitro and in-vivo assays. Ultra-high performance liquid chromatography (UHPLC) analysis revealed the presence of phytocompounds including gallic acid, methyl gallate, corilagin, ellagic acid, pentagalloyl glucose, withaferin A and hydroxycitric acid, proven to aid in weight loss. The exposure of 3T3-L1 cells to DWG at cytosafe concentrations inhibited lipid and triglyceride accumulation and downregulated the expression of several adipogenic and lipogenic markers like PPARy, C/EBPα, C/EBPβ, SREBP-1c, FASN and DGAT1. DWG reduced LPS-induced pro-inflammatory cytokine release and NF-κB activity in THP-1 cells. The in-vivo anti-obesity activity of DWG, both alone and in combination with moderate aerobic exercise, was assessed in a high fat diet-induced obese mouse model. DWG mitigated the obesity associated increased body weight gain, feed efficiency ratio, glucose intolerance, diminished insulin sensitivity, dyslipidemia, altered liver function profile, lipid accumulation and adiposopathy in obese mice, alone as well as in combination intervention, with better efficacy in the combination approach. Thus, the findings of this study suggest that DWG could be a promising therapeutic avenue to treat obesity through attenuation of lipid and fat accumulation in liver and adipose tissues and could be utilized as an adjunct with lifestyle interventions to combat obesity and associated complications.

Inhibitory Effects of Hydrolysable Tannins on Lipid Accumulation in 3T3-L1 Cells

Obesity is currently the most common cause of metabolic diseases including type 2 diabetes and hyperlipidemia. Obesity results from excess lipid accumulation in adipose tissue. Several studies have investigated the inhibitory effects of natural plant-derived products on adipocyte differentiation and lipid accumulation. In this study, we examined the effect of hydrolysable tannins composed of gallic acid and glucose on adipocyte differentiation in 3T3-L1 cells. 1,2,3,4,6-Penta-O-galloyl-β-D-glucose (PGG) (1), a representative gallotannin, inhibited lipid accumulation in 3T3-L1 cells, whereas ellagitannins (tellimagrandin I, eugeniin and casuarictin) did not. The expression of adipocyte differentiation-related genes, including peroxisome proliferator activator γ2 (Pparγ2), CCAAT/enhancer binding protein α (C/EBPα) and adipocyte fatty acid binding protein (aP2), was significantly suppressed in PGG (1)-treated 3T3-L1 cells beginning at day 2 after induction of differentiation. While PGG (1) did not directly reduce Pparγ2 expression, it reduced the expression of its target genes in mature adipocytes. In addition, PGG (1) treatment inhibited mitotic clonal expansion, one of earliest events of adipocyte differentiation. These findings indicate that PGG (1) has an inhibitory effect on adipocyte differentiation through the suppression of mitotic clonal expansion.

Natural polyphenols: a potential prevention and treatment strategy for metabolic syndrome

Metabolic syndrome (MS) is the term for a combination of hypertension, dyslipidemia, insulin resistance, and central obesity as factors leading to cardiovascular and metabolic disease. Epidemiological investigation has shown that polyphenol intake is negatively correlated with the incidence of MS. Natural polyphenols are widely found in cocoa beans, tea, vegetables, fruits, and some Chinese herbal medicines; they are a class of plant compounds containing a variety of phenolic structural units, which are potent antioxidants and anti-inflammatory agents in plants. Polyphenols are composed of flavonoids (such as flavanols, anthocyanidins, anthocyanins, isoflavones, etc.) and non-flavonoids (such as phenolic acids, stilbenes, and lignans). Modern pharmacological studies have proved that polyphenols can reduce blood pressure, improve lipid metabolism, lower blood glucose, and reduce body weight, thereby preventing and improving MS. Due to the unique characteristics and potential development and application value of polyphenols, this review summarizes some natural polyphenols that could treat MS, including their chemical properties, plant sources, and pharmacological action against MS, to provide a basis for the further study of polyphenols in MS.

Corilagin prevents non-alcoholic fatty liver disease via improving lipid metabolism and glucose homeostasis in high fat diet-fed mice

Non-alcoholic fatty liver disease (NAFLD) has been considered to be one of the most common chronic liver diseases. However, no validated pharmacological therapies have been officially proved in clinic due to its complex pathogenesis. The purpose of this study was to examine the protective effects of Corilagin (referred to Cori) against NAFLD in mice under a high fat diet (HFD) condition. Mice were fed either a normal control diet (NCD) or HFD with or without Cori (5 or 10 mg/kg body weight) for 15 weeks. In our results, Cori treatment significantly attenuated HFD-induced hepatic steatosis, high NAFLD activity score (NAD) and liver injury. Consistently, Cori treatment remarkably alleviated HFD-induced hepatic lipid accumulation (e.g., triglycerides (TG) and total cholesterol (TC) contents in liver), and improved plasma lipid concentrations (e.g., plasma TG, TC, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c)). Moreover, Cori treatment ameliorated NAFLD associated metabolic disorders such as glucose intolerance and insulin resistance in HFD-fed mice. Additionally, Cori treatment dramatically changed HFD-induced liver gene expression profiles, and identified overlapped differentially expressed genes (DEGs) between NCD vs. HFD group and HFD vs. HCR (high fat diet plus treatment with Cori) group. With these DEGs, we observed a marked enrichment of Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, which were closely associated with the metabolic balance in liver. Particularly, we found several potential hub proteins against NAFLD development with analyses of protein-protein interaction (PPI) network and qPCR assays. Collectively, our results revealed the important protective effects of Cori against the progress of NAFLD, which was probably mediated through improving dysregulated lipid metabolism and insulin resistance in HFD-fed mice. Additionally, Cori-dependent overlapped DEGs might serve as a featured NAFLD-associated gene expression signature for the diagnosis, treatment, as well as drug discovery and development of NAFLD in the near future.

Investigation of the inhibition effect of 1,2,3,4,6-pentagalloyl-β-D-glucose on gastric cancer cells based on a network pharmacology approach and experimental validation

Background

Gastric cancer (GC) is ranked as the third leading cause of cancer-related mortality worldwide. 1,2,3,4,6-Pentagalloyl-β-D-glucose (β-PGG) has various pharmacological activities and has been shown to suppress cancer development. However, the mechanism by which β-PGG inhibits gastric cancer has not been elucidated.

Objective

This study explored the potential targets and mechanism of β-PGG in GC using the network pharmacology approach combined with in-vitro experiments.

Methods

The PharmMapper software was used to predict the potential targets of β-PGG, and GC-related genes were identified on the GeneCards database. PPI analysis of common genes was performed using the STRING database. The potential regulatory mechanism of β-PGG in GC was explored through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The binding ability of key genes and target proteins was verified by molecular docking. The effects of β-PGG on genes and proteins were evaluated using the CCK-8 assay, cell cycle analysis, apoptosis assay, real-time fluorescence quantification polymerase chain reaction (qRT-PCR), and Western blotting.

Results

Eight hub genes involved in cell cycle progression and apoptosis were identified. Cancer-related signaling pathways were identified using the Cytoscape tool. Some of those genes were significantly enriched in the p53 signaling pathway. The CCK-8 assay showed that β-PGG inhibited the proliferation of GC cells. Cell cycle and apoptosis experiments revealed that β-PGG induced cell cycle arrest and apoptosis of gastric cancer cells. qRT-PCR and Western blot analysis showed that β-PGG inhibited β-PGG cells by modulating the p53 signaling pathway.

Conclusion

In the present study, the targets and mechanism of β-PGG in gastric cancer were explored. The results indicate that β-PGG can be used to develop treatments for GC.

Tamoxifen induced hepatic steatosis in high-fat feeding rats through SIRT1-Foxo1 suppression and LXR-SREBP1c activation

Background

Clinically, long-term use of tamoxifen (TAM) would lead to fatty liver disease in breast cancer patients, especially obese women. However, the exact mechanism of TAM-induced hepatic steatosis is still unclear. Meanwhile, there is no drug to prevent and treat it.

Aims and Methods

In view of silent information regulator 1 (SIRT1) playing a key role in hepatic lipid metabolism regulation, this study was conducted to investigate whether SIRT1 is a potential therapeutic target for TAM-induced hepatic steatosis. In this study, obese female Wistar rats fed with high-fat diet (HFD) for 15 weeks were given TAM (4, 8 mg/kg, intragastric) for 14 days. In vitro, human hepatocarcinoma cell line HepG2 was used to establish a high-fat model with 50 μM oleic acid and TAM (10 μM) was treated simultaneously for 72 h.

Results

The results showed that TAM was more likely to upregulate the expression of lipid synthetase that caused the increase of lipid content in HepG2 cells and rat liver. The expression of SIRT1 was downregulated both in vitro and in vivo. SIRT1 agonist SRT1720 (15 mg/kg, 30 mg/kg, i.p.) could resist TAM-induced hepatic lipid synthetase overexpression to relieve TAM-induced hepatic steatosis. Meanwhile, the upregulation of p-forkhead box O1 and LXRα induced by TAM was reversed by SRT1720.

Conclusions

These results indicated that TAM-induced hepatic steatosis was based on SIRT1-p-FoxO/LXRα-sterol regulatory element binding protein 1c pathway under HFD condition. SIRT1 agonist might be a potential therapeutic drug to relieve this side effect.

Highlights

Tamoxifen increased lipid synthesis and regulated lipid transport in HFD rat liver.p-FoxO1/LXRα-SREBP1c signaling was upregulated through the inhibition of SIRT1 in tamoxifen-induced hepatic steatosis under HFD condition.SIRT1 agonist SRT1720 could relieve tamoxifen-induced hepatic steatosis.

Natural Polyphenols in Metabolic Syndrome: Protective Mechanisms and Clinical Applications

Metabolic syndrome (MetS) is a chronic disease, including abdominal obesity, dyslipidemia, hyperglycemia, and hypertension. It should be noted that the occurrence of MetS is closely related to oxidative stress-induced mitochondrial dysfunction, ectopic fat accumulation, and the impairment of the antioxidant system, which in turn further aggravates the intracellular oxidative imbalance and inflammatory response. As enriched anti-inflammatory and antioxidant components in plants, natural polyphenols exhibit beneficial effects, including improving liver fat accumulation and dyslipidemia, reducing blood pressure. Hence, they are expected to be useful in the prevention and management of MetS. At present, epidemiological studies indicate a negative correlation between polyphenol intake and MetS incidence. In this review, we summarized and discussed the most promising natural polyphenols (including flavonoid and non-flavonoid drugs) in the precaution and treatment of MetS, including their anti-inflammatory and antioxidant properties, as well as their regulatory functions involved in glycolipid homeostasis.

Herp knockout protects against nonalcoholic fatty liver disease in mice on a high fat diet

This study aims to discover the role of Homocysteine-induced ER protein (Herp) deficiency in high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD). After 8 weeks of feeding with normal-fat diet (NFD) or HFD, WT (wild type) and Herp^-/- mice were measured for the body weight, liver weight and serum biochemical parameters. HE, Oil Red O, and Sirius red stainings were used to evaluate the histopathological changes of liver tissues. QRT-PCR, Western blotting and Immunohistochemistry were employed to detect the mRNA and protein expression. TUNEL staining was used to observe the hepatocyte apoptosis. Herp knockout reduced the liver/body weight ratio of mice fed with HFD with the decreased serum levels of TG, TC, HDL, LDL, GGT, Hcy, ALT, and AST. Besides, WT mice fed with HFD presented obvious steatosis, inflammation and hepatocytes ballooning, which was relieved in Herp^-/- mice. HFD-induce NFALD mice demonstrated increased Oil Red, Sirius red, and α-SMA staining than NFD-induced mice, but mice in the Herp^-/-  + HFD group was lower than the WT + HFD group. HFD-induce NFALD mice showed up-regulated expression of Grp78, Chop, and Atf4 in liver tissues when compared with NFD fed mice. However, regarding to the mice fed with HFD, Herp deficiency decrease in the expression of Grp78, Chop, and Atf4 in liver tissues with the reduced hepatocyte apoptosis. Herp was highly expressed in HFD-induced NAFLD mice. Herp knockout improved liver function and histopathological conditions with the decreased hepatocyte apoptosis and endoplasmic reticulum stress (ERS) of HFD-induce NFALD mice.