2,3,5,4'-tetrahydroxy-stilbene-2-O-β-D-glucoside ameliorates NAFLD via attenuating hepatic steatosis through inhibiting mitochondrial dysfunction dependent on SIRT5

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is becoming more and more common in clinic in the world, and the study on its mechanism and treatment strategy has already been a research hotspot. Natural chemical compound 2,3,5,4'-tetrahydroxy-stilbene-2-O-β-d-glucoside (TSG) is isolated from Polygonum multiflorum Thunb. that has already been reported to have the lipid-lowering activity.

PURPOSE

The purpose of this research was to observe the improvement of TSG on methionine and choline deficient (MCD) diet-induced NAFLD in mice and to further elucidate its engaged mechanism.

METHODS

NAFLD was induced in mice fed by MCD diet for 6 weeks. The accumulation of lipids in hepatocytes was induced by 0.5 mM non-esterified fatty acid (NEFA). Biochemical parameters in serum or livers from mice were tested. Protein and mRNA expression and stability were measured. Mitochondrial dysfunction was analyzed both in vivo and in vitro. The Label-free quantitative proteomic analysis was used to find potential involved key molecules.

RESULTS

TSG attenuated hepatic parenchymal cells injury, liver inflammatory responses and hepatic fibrosis, and markedly ameliorated liver steatosis in mice from MCD group. In vitro results indicated that TSG reduced the accumulation of cellular lipids in hepatocytes induced by NEFA. TSG reduced reactive oxygen species (ROS) formation and attenuated mitochondrial dysfunction both in vivo and in vitro. The label-free quantitative proteomic analysis predicted the crucial participation of NAD-dependent protein deacylase sirtuin-5 (SIRT5). Next experimental results further evidenced that TSG enhanced SIRT5 expression in mitochondria both in vitro and in vivo. The TSG-supplied inhibition on ROS formation and mitochondrial dysfunction in hepatocytes was disappeared after the application of SIRT5 siRNA. TSG increased the expression and enzymatic activity of carnitine palmitoyltransferase 1A (CPT1A), but this enhance was diminished in hepatocytes transfected with SIRT5 siRNA. Additionally, the TSG-provided inhibition on cellular lipids accumulation was also disappeared in hepatocytes transfected with SIRT5 siRNA. Further results demonstrated that TSG increased SIRT5 expression by regulating its mRNA stability through enhancing the binding of SIRT5 mRNA with serine/arginine-rich splicing factor 2 (SRSF2), which is an RNA-binding protein (RBP).

CONCLUSION

TSG attenuated liver steatosis and inhibited NAFLD progression through preventing oxidative stress injury and improving mitochondrial dysfunction, and SIRT5 played a key role in this process.

Tetrahydroxy stilbene glycoside ameliorates Alzheimer's disease in APP/PS1 mice via glutathione peroxidase related ferroptosis

Amyloid beta peptide (Aβ) has been confirmed to be an essential reason of Alzheimer's disease (AD) for a long time. Ferroptosis is a newly recognized oxidative cell death mechanism, which is highly related to AD. Recently, tetrahydroxy stilbene glycoside (TSG) has been beneficial in alleviating learning and memory of AD and aged mouse model. Unfortunately, the underlying mechanisms between TSG and ferroptosis in AD are poorly understood. Herein, we investigated whether neural cells in cerebral cortex and hippocampus that were seriously afflicted in APP/PS1 mice might be vulnerable to ferroptosis. Treatment with non-toxic TSG dose-dependently resisted Aβ-caused cytotoxic death in neuronal cells by regulating ferroptosis related proteins and enzymes in APP/PS1 mice. TSG also alleviated cellular oxidative stress and inflammatory damage in response to Aβ by attenuating the levels of oxidation products. Importantly, TSG administration abrogated Aβ-caused brain damage, indicating that TSG rescued brain cells. Subsequently, TSG promoted the activation of GSH/GPX4/ROS and Keap1/Nrf2/ARE signaling pathways. Notably, markers related to ferroptosis including increased lipid peroxidation, enhanced neuroinflammation such as NLRP3, and also the expression of DMT1, ACSL4 and NCOA4, were reduced by TSG administration. In addition, TSG enhanced antioxidative stress via the upregulation of SOD, and the expression of FTH1, CD98 and xCT. Taken together, our data indicated a novel mechanism of TSG in reversing Aβ-caused injury through restoring mitochondrial function via several signaling pathways, implying a promising candidate against neurodegenerative diseases especially AD. Hence, TSG should be taken into consideration during treatment of AD in the future.

An integrated deep learning and dynamic programming method for predicting tumor suppressor genes, oncogenes, and fusion from PDB structures

Mutations in proto-oncogenes (ONGO) and the loss of regulatory function of tumor suppression genes (TSG) are the common underlying mechanism for uncontrolled tumor growth. While cancer is a heterogeneous complex of distinct diseases, finding the potentiality of the genes related functionality to ONGO or TSG through computational studies can help develop drugs that target the disease. This paper proposes a classification method that starts with a preprocessing stage to extract the feature map sets from the input 3D protein structural information. The next stage is a deep convolutional neural network stage (DCNN) that outputs the probability of functional classification of genes. We explored and tested two approaches: in Approach 1, all filtered and cleaned 3D-protein-structures (PDB) are pooled together, whereas in Approach 2, the primary structures and their corresponding PDBs are separated according to the genes' primary structural information. Following the DCNN stage, a dynamic programming-based method is used to determine the final prediction of the primary structures' functionality. We validated our proposed method using the COSMIC online database. For the ONGO vs TSG classification problem the AUROC of the DCNN stage for Approach 1 and Approach 2 DCNN are 0.978 and 0.765, respectively. The AUROCs of the final genes' primary structure functionality classification for Approach 1 and Approach 2 are 0.989, and 0.879, respectively. For comparison, the current state-of-the-art reported AUROC is 0.924. Our results warrant further study to apply the deep learning models to humans' (GRCh38) genes, for predicting their corresponding probabilities of functionality in the cancer drivers.

2,3,5,4'-Tetrahydroxy-stilbene-2-O-beta-d-glucoside induces autophagy-mediated apoptosis in hepatocytes by upregulating miR-122 and inhibiting the PI3K/Akt/mTOR pathway: implications for its hepatotoxicity

CONTEXT

The potential hepatotoxicity of Polygoni Multiflori Radix (PMR) has attracted much attention, but the specific mechanism of inducing hepatotoxicity is still unclear due to the complexity of its components.

OBJECTIVE

This study investigated the specific mechanism by which 2,3,5,4'-tetrahydroxy-stilbene-2-O-β-d-glucoside (TSG) regulates hepatotoxicity.

MATERIALS AND METHODS

The toxic effects of TSG (10, 100, 1000 μg/mL) on WRL-68 cells were examined using MTT, flow cytometry, and LDH assay after 24 h of incubation. Untreated cells served as the control. Gene and protein expression levels were determined by quantitative real-time PCR and Western blot, respectively. Immunofluorescence analysis was conducted to investigate the expression of light chain 3 (LC3). Luciferase activity assay was used to assess the targeted regulation of RUNX1 by miR-122.

RESULTS

The half maximal inhibitory concentration (IC50) of TSG in WRL-68 cells was calculated as 1198.62 μg/mL. TSG (1000 μg/mL) inhibited cell viability and LDH activity and promoted WRL-68 cell apoptosis by inducing autophagy. Subsequent findings showed that TSG induced autophagy and promoted apoptosis in WRL-68 cells by downregulating the levels of p-PI3K, p-Akt, and p-mTOR proteins, while RUNX1 overexpression rescued this inhibition. Additionally, the effect of TSG on hepatocyte apoptosis was reversed by miR-122 knockdown. Furthermore, bioinformatics and dual luciferase reporter assay results indicated that miR-122 targeted RUNX1.

DISCUSSION AND CONCLUSIONS

Our data demonstrate for the first time that TSG regulates hepatotoxicity, possibly by upregulating miR-122 and inhibiting the RUNX1-mediated PI3K/Akt/mTOR pathway to promote autophagy and induce hepatocyte apoptosis. Further in vivo research is necessary to verify our conclusion.

Stilbene Glycoside Oligomers from the Roots of Polygonum multiflorum

Five new trans-2,3,5,4'-tetrahydroxystilbene 2-O-β-d-glucopyranoside (TSG)-based stilbene glycoside oligomers (1-5) were isolated from the roots of Polygonum multiflorum. Their structures were elucidated by comprehensive spectroscopic analyses and chemical evidences. The absolute configurations of 1, 2, 4, and 5 were established by quantum-chemical electronic circular dichroism (ECD) calculations. Putative biosynthetic pathways of 1-5 were proposed using TSG as the key precursor. In addition, compounds 1 (multiflorumiside H) and 3 (multiflorumiside J) exhibited moderate inhibitory activities against NO production in LPS-stimulated RAW264.7 cells.

2,3,5,4'-tetrahydroxy-stilbene-2-O-β-D-glucoside attenuates methionine and choline-deficient diet-induced non-alcoholic fatty liver disease

Previous studies have suggested that 2,3,5,4′-tetrahydroxy-stilbene-2-O-β-D-glucoside (TSG) prevents progression of non-alcoholic fatty liver disease (NAFLD) induced by high-fat diet. The present study aimed to evaluate whether TSG could reverse NAFLD induced by a methionine and choline-deficient (MCD) diet and identify the possible mechanism of action. C57BL6/J mice were fed a MCD diet and were treated with TSG, fenofibrate, and resveratrol for 9 weeks. Regulatory effects of several cytokines and enzymes, including Nod-like receptor protein 3, apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC), caspase-1, interleukin (IL)-18, IL-1β, and gut microbiota balance were investigated. TSG significantly reduced NAFLD biochemical indexes, including total cholesterol, triglyceride, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, aspartate aminotransferase and free fatty acid. Middle dosage (TSG.M, 35 mg/kg) of TSG reduced the expression of ASC and caspase-1. Furthermore, TSG displayed gut microbiota regulatory effects on MCD-induced NAFLD mice. The results of the present study suggested that TSG prevented the occurrence and development of MCD diet-induced NAFLD. The data further indicated that TSG may serve as a promising lead compound that may aid with intervention in NAFLD therapy.

25 years of European Union (EU) quality schemes for agricultural products and foodstuffs across EU Member States

Consumers are increasingly turning their attention to the quality and origin of products that they consume. European Union (EU) quality schemes are associated with a label, which was introduced to allow consumers to perform an informed choice and to protect producers from unfair practices. This present study provides an overview of the last 25 years of EU quality schemes [Protected Designations of Origin (PDO), Protected Geographical Indications (PGI) and Traditional Specialities Guaranteed (TSG)] on agricultural products and foodstuffs across the 28 EU Member States. According to the results, it was possible to conclude that Southern European countries have the highest number of registered products. The most used EU quality scheme is PGI, followed by PDO. Concerning the analysis of the evolution in the last 25 years, the number of registered products among EU Member States has increased significantly. The fruit, vegetables and cereals (fresh or processed) category is the one that accounts for the highest percentage (26.8%) of registered products, followed by cheeses and meat products (cooked, salted, smoked) categories, with 17.2% and 13.5%, respectively. Further investigations should address consumer preferences, knowledge and attitudes, especially Northern European countries with a lower number of registered products. Moreover, the investigation and registration of products should be encouraged among all EU Member States to allow the maintenance of important elements of the history, culture and heritage of the local areas, regions and countries. © 2017 Society of Chemical Industry.

Protective effect of TSG against oxygen-glucose deprivation in cardiomyoblast cell line H9c2: involvement of Bcl-2 family, Caspase 3/9, and Akt signaling pathway

OBJECTIVE

This study was designed to investigate the effect of TSG (2, 3, 5, 4'-tetrahydroxystibene-2-O-β-D-glucoside) on ischemic cardiomyopathy (ICM) related cell apoptosis and the mechanism related to it in vitro.

METHODS

Rat cardiomyoblast cell line H9c2 was cultured in oxygen-glucose withdrawal medium for 8 hours to establish an in vitro cell model of oxygen-glucose deprivation (OGD). Cells were pretreated with TSG to test the protective effect of it against OGD. Cell viability, apoptosis, mitochondrial transmembrane potential (ΔΨ_m), and apoptosis related proteins were detected using appropriated methods. Differences between treatments were analyzed.

RESULTS

OGD treatment inhibited cell viability, expression of Akt and Bax, induced loss of ΔΨ_m, cell apoptosis, and triggered expression of Bcl-2 and Caspase-3/9. TSG pretreatment, on the contrary, suppressed OGD-induced cell apoptosis, ΔΨ_m loss, Bcl-2 and Caspase-3/9 expression, and promoted OGD-inhibited cell viability, Bax and Akt expression.

CONCLUSION

We concluded that TSG's protective effect against OGD-induced in vitro ischemic cell model was associated to Akt/Caspase-3 pathway. TSG might be explored as a therapeutic target for ICM.

Protected Designation of Origin (PDO), Protected Geographical Indication (PGI) and Traditional Speciality Guaranteed (TSG): A bibiliometric analysis

Despite the importance of the literature on food quality labels in the European Union (PDO, PGI and TSG), our search did not find any review joining the various research topics on this subject. This study aims therefore to consolidate the state of academic research in this field, and so the methodological option was to elaborate a bibliometric analysis resorting to the term co-occurrence technique. Analysis was made of 501 articles on the ISI Web of Science database, covering publications up to 2016. The results of the bibliometric analysis allowed identification of four clusters: "Protected Geographical Indication", "Certification of Olive Oil and Cultivars", "Certification of Cheese and Milk" and "Certification and Chemical Composition". Unlike the other clusters, where the PDO label predominates, the "Protected Geographical Indication" cluster covers the study of PGI products, highlighting analysis of consumer behaviour in relation to this type of product. The focus of studies in the "Certification of Olive Oil and Cultivars" cluster and the "Certification of Cheese and Milk" cluster is the development of authentication methods for certified traditional products. In the "Certification and Chemical Composition" cluster, standing out is analysis of the profiles of fatty acids present in this type of product.

TSG attenuates LPC-induced endothelial cells inflammatory damage through notch signaling inhibition

Lysophosphatidylcholine (LPC) induces inflammation in endothelial cells (ECs) but the mechanism is not fully understood. The Notch signaling pathway is involved in chronic EC inflammation, but its functions in LPC-induced endothelial inflammatory damage and 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside's (TSG) protective effect during LPC-induced inflammatory damage in human umbilical vein endothelial cells (HUVECs) is largely unknown. We report that Notch signaling activation contributed to LPC-induced injury in HUVECs, and that TSG protected HUVECs from LPC-induced injury by antagonizing Notch signaling activation by LPC. γ-secretase inhibitor (DAPT), a specific inhibitor of the Notch signaling pathway, and Notch1 siRNA were used to inhibit Notch activity. HUVECs were exposed to LPC in the presence or absence of TSG, DAPT, and Notch1 siRNA. LPC treatment of HUVECs resulted in reduced cell viability, and Notch1 and Hes1 upregulation. Either silencing of Notch1 by siRNA or pharmacological inhibition of Notch signaling by DAPT prevented the loss of cell viability, and induction of apoptosis, and enhanced expression Notch1, Hes1 and MCP-1 by LPC in HUVECs. Similarly, TSG reduced LPC stimulation of Notch1, Hes1, and MCP-1 expression, prevented the release of IL-6 and CRP and rescued HUVECs from LPC-induced cell damage. Our data indicate that the Notch signaling pathway is a crucial mediator of endothelial inflammatory damage and that TSG protects against endothelial inflammatory damage by inhibiting the Notch signaling pathway. Our findings suggest that targeting Notch signaling by natural products such as TSG is a promising strategy for the prevention and treatment of chronic inflammation associated diseases, including atherosclerosis. © 2015 IUBMB Life, 68(1):37-50, 2016.

Methylation of a novel panel of tumor suppressor genes in urine moves forward noninvasive diagnosis and prognosis of bladder cancer: a 2-center prospective study

PURPOSE

Changes in DNA methylation of tumor suppressor genes early in carcinogenesis represent potential indicators of cancer detection and disease evolution. We examined the diagnostic, stratification and prognostic biomarker roles in urine of the methylation of a novel panel of tumor suppressor genes in bladder cancer.

MATERIAL AND METHODS

We evaluated the methylation of 18 tumor suppressor genes in 2 prospective, independent sets of urine samples (training set of 120 preparations and validation set of 128) from patients with bladder cancer (170) and controls (78) using methylation specific multiplex ligation-dependent probe amplification. Diagnostic performance was evaluated with ROC curves. Recurrence, progression and disease specific survival were analyzed using univariate and multivariate Cox models.

RESULTS

PRDM2, HLTF, ID4, DLC1, BNIP3, H2AFX, CACNA1G, TGIF and CACNA1A were methylated in bladder cancer. CCND2, SCGB3A1, BNIP3, ID4 and RUNX3 were the most frequently methylated tumor suppressor genes in each urine set. Methylation of several tumor suppressor genes correlated with clinicopathological variables, such as stage, tumor grade, focality or age. ROC analysis revealed significant diagnostic accuracy for RUNX3 and CACNA1A in the training set, and for RUNX3 and ID4 in the validation set. On univariate and multivariate analysis CACNA1A methylation correlated with recurrence in the training set, while in the validation set PRDM2 and BNIP3 were significantly associated with recurrence and disease specific survival, respectively.

CONCLUSIONS

Tumor suppressor gene methylation allowed for histopathological and clinical stratification. Urine methylation has noninvasive usefulness not only for diagnostic assessment but also as independent bladder cancer prognosticators.