Effects Of Tetrahydroxystilbene-2-O-β-D-glucoside Research Articles

2,3,5,4-Tetrahydroxystilbene-2-O-Β-D-Glucoside Inhibiting Hepatocytes Injury Through Reducing the Expression of Tumor Necrosis Factor-a in LPSStimulated Kupffer Cells via Regulating PPAR-γ/NFκB

2,3,5,4'-Tetrahydroxystilbene-2-O-Β-D-Glucoside (TSG), a main bioactive component of polygonum multiflorum Thumb, exerts anti-oxidant, antitumor, anti-inflammatory effects. However, the protective effects of TSG on hepatocytes through anti-inflammatory effects have rarely been investigated. Mouse liver macrophages (Kupffer cells, KUP5 cells) were primed with various concentrations of TSG before Lipopolysaccharide (LPS) treatment, and AML12 hepatocytes were cultured with the supernatants of KUP5 cells. The results showed that TSG inhibits the expression of iNOS in KUP5 cells. Meanwhile, Tumor Necrosis Factor-a (TNF-a) and interleukin-1Β (IL-1Β) expression in KUP5 cells were reversed after TSG treatment. Additionally, the expression of Peroxisome Proliferators-Activated Receptors-γ (PPAR-γ) was up-regulated while the phosphorylation of p65 and IκB-a were decreased in KUP5 cells after TSG treatment. Furthermore, GW9662 (PPAR-γ antagonist) treatment could eliminate the anti-inflammatory effects of TSG. In AML12 hepatocytes, the level of AST, ALT, and apoptosis was decreased after being cultured with the supernatants of KUP5 cells pretreated with TSG. Moreover, TNF-a neutralization of KUP5 cells supernatants could decrease the level of AST, ALT, and AML12 hepatocyte apoptosis. These results indicate that TSG activates PPAR-γ, thereby decreasing nuclear factor kappa-B (NFκB) activation and reducing the release of TNF-a in macrophages to protect hepatocytes from injury. Our study may help further understand the protective effects of TSG on hepatocytes by suppressing liver inflammation.

2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-Glucoside improves female ovarian aging.

Reduced fertility associated with normal aging may reflect the over-maturity of oocytes. It is increasingly important to reduce aging-induced infertility since recent trends show people marrying at later ages. 2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-glucoside (THSG), a polyphenol extracted from Polygonum multiflorum, has been reported to have anti-inflammatory and anti-aging properties. To evaluate whether THSG can reduce aging-related ovarian damage in a female mouse model of aging, THSG was administered by gavage at a dose of 10 mg/kg twice weekly, starting at 4 weeks of age in a group of young mice. In addition, the effect of THSG in a group of aged mice was also studied in mice starting at 24 weeks of age. The number of oocytes in the THSG-fed group was higher than in the untreated control group. Although the percentage of secondary polar bodies (PB2) decreased during aging in the THSG-fed group, it decreased much more slowly than in the age-matched control group. THSG administration increased the quality of ovaries in young mice becoming aged. Western blotting analyses also indicated that CYP19, PR-B, and ER-β expressions were significantly increased in 36-week-old mice. THSG also increased oocyte numbers in aged mice compared to mice without THSG fed. Studies of qPCR and immunohistochemistry (IHC) analyses of ovaries in the aged mice groups were conducted. THSG increased gene expression of anti-Müllerian hormone (AMH), a biomarker of oocyte number, and protein accumulation in 40-week-old mice. THSG increased the expression of pgc1α and atp6, mitochondrial biogenesis-related genes, and their protein expression. THSG also attenuated the fading rate of CYP11a and CYP19 associated with sex hormone synthesis. And THSG maintains a high level of ER-β expression, thereby enhancing the sensitivity of estrogen. Our findings indicated that THSG increased or extended gene expression involved in ovarian maintenance and rejuvenation in young and aged mice. On the other hand, THSG treatments significantly maintained oocyte quantity and quality in both groups of young and aged mice compared to each age-matched control group. In conclusion, THSG can delay aging-related menopause, and the antioxidant properties of THSG may make it suitable for preventing aging-induced infertility.

TSG Targeting KDM5A Affects Osteogenic Differentiation of Bone Mesenchymal Stem Cells Induced by Bone Morphogenetic Protein 2.

Objectives To investigate the effect of 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (TSG) on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and its molecular mechanism. Methods After TSG treatment of rBMSCs, alkaline phosphatase (ALP) activity was compared between the drug treatment group and the control group. The effects of TSG on alkaline phosphatase positive cloning and mineralized nodule formation were also detected. Total mRNA and protein were extracted, and the effects of TSG on the expression levels of osteopontin (OPN), osteocalcin (OCN), Runt-related transcription factor 2 (Runx2), Osterix, and Col1a1 were detected by real-time fluorescence quantitative PCR. Western blotting was used to detect the inhibitory effect of TSG on KDM5A. BMSCs were transfected with small interfering RNA (siRNA) targeting KDM5A (si-KMD5A) and pcDNA3.1 KMD5A. Results TSG significantly increased the activity of ALP, the number of alkaline phosphatase clones, and calcified nodule formation. The OPN, OCN, Runx2, and Osterix expression levels were significantly increased among the osteoblasts after TSG treatment. A mechanistic study showed that the effect of TSG is realized by inhibiting KDM5A. Conclusions KDM5A signaling may be involved in the regulation of osteogenic differentiation of rBMSCs. TSG can promote osteogenic differentiation and maturation of rBMSCs at 0.1–50 μmol/L. The mechanism of action was realized by inhibiting the expression of KDM5A.

The Protective Effect of Tetrahydroxystilbene Glucoside on High Glucose-Induced Injury in Human Umbilical Vein Endothelial Cells through the PI3K/Akt/eNOS Pathway and Regulation of Bcl-2/Bax

Endothelial dysfunction plays a central role in the patho­genesis of diabetic vascular complications. 2,3,5,4′-tetra­hydroxystilbene-2-O-β-D-glucoside (TSG), an active component extracted from the roots of Polygonum multiflorum Thunb, has been shown to have strong antioxidant and antiapoptotic activities. In the present study, we investigated the protective effect of TSG on apoptosis induced by high glucose in human umbilical vein endothelial cells (HUVECs) and the possible mechanisms. Our data demonstrated that TSG significantly reversed the high glucose-induced decrease in cell viability, suppressed high glucose-induced generation of intracellular reactive oxygen species (ROS), the activity of caspase-3, and decreased the percentage of apoptotic cells in a dose-dependent manner. In addition, we found that TSG not only increased the expression of Bcl-2, while decreasing Bax expression, but also activated phosphorylation of Akt and endothelial nitric oxide synthase (eNOS) with subsequent nitric oxide production and ultimately reduced high glucose-induced apoptosis. However, the antiapoptotic effects of TSG were abrogated by pretreatment of the cells with PI3K inhibitor (LY294002) or eNOS inhibitor NG-L-nitro-arginine methyl ester, respectively. These results suggest that TSG inhibits high glucose-induced apoptosis in HUVECs through inhibition of ROS production, activation of the PI3K/Akt/eNOS pathway, and upregulation of the Bcl-2/Bax ratio, and thus may demonstrate significant potential for preventing diabetic cardiovascular complications.

2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-Glucoside modulated human umbilical vein endothelial cells injury under oxidative stress.

Endothelial cell injury is a major contributor to cardiovascular diseases. The 2,3,5,4’-Tetrahydroxystilbene-2-O-β-D-Glucoside (TSG) contributes to alleviate human umbilical vein endothelial cells (HUVECs) injury through mechanisms still know a little. This study aims to clarify the TSG effects on gene expression (mRNA and microRNA) related to oxidative stress and endoplasmic reticulum stress induced by H2O2 in HUVECs. We found that TSG significantly reduced the death rate of cells and increased intracellular superoxide dismutase activity. At qRT-PCR, experimental data showed that TSG significantly counteracted the expressions of miR-9-5p, miR-16, miR-21, miR-29b, miR-145-5p, and miR-204-5p. Besides, TSG prevented the expression of ATF6 and CHOP increasing. In contrast, TSG promoted the expression of E2F1. In conclusion, our results point to the obvious protective effect of TSG on HUVECs injury induced by H2O2, and the mechanism may through miR16/ATF6/ E2F1 signaling pathway.

SIRT1 Is the Target Gene for 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-Glucoside Alleviating the HUVEC Senescence.

This study aimed to explore the effects of 2,3,5,4’-tetrahydroxy-stilbene-2-O-β-d-glucoside (TSG) on the senescence of human umbilical vein cells (HUVEC) induced by hydrogen peroxide (H2O2) and to identify the potential targets mediating its protective action. HUVEC cells pre-treated with TSG for 24 h were exposed to H2O2 treatment. TSG significantly decreased H2O2-induced cellular senescence, as indicated by reduced senescence-associated β-galactosidase (SA-β-gal) positive staining, the proportion of cells in the G1 phase, cell apoptosis, p21, and plasminogen activator inhibitor-1 (PAI-1) expression. Moreover, TSG promoted Sirtuin 1 (SIRT1) expression. When SIRT1 was inhibited by EX527 or SIRT1 siRNA, the effect of TSG is diminished according to the increased proportion of cells in the G1 phase, cell apoptosis, p21, and PAI-1 expression. Overall, our study established TSG as an anti-senescence compound that exerts its protective action by regulating SIRT1 expression.

2,3,5,4\u2032-tetrahydroxystilbene-2-O-\u03b2-D-glucoside induces autophagy of liver by activating PI3K/Akt and Erk pathway in prediabetic rats

Background2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (TSG) is an active compound derived from Polygonum multiflorum Thunb., a Chinese Taoist herbal medicine, which exerts lipid lowering, anti-cancer, anti-aging, anti-inflammatory and hepatoprotective effects. However, its role in protecting hepatocytes under pre-diabetic condition remains unclear.MethodsIn this study, we developed prediabetic SD rats by feeding high-fat and high-sugar diet. The body weight, blood lipid, blood glucose, and fasting insulin (FINS) and insulin resistance index (HOMA-IR) were detected and calculated to assess the potential risk of prediabetes. HE and Oil Red O staining was used, and blood level of biochemical index was detected to observe the liver injury. The autophagic cell death-associated signaling proteins, and the potential signaling factors p-Akt/Akt and p-Erk/Erk were detected using western blot to explore the potential effects of TSG on pre-diabetic liver and the underlying mechanisms.ResultsThe results showed that the body weight in TSG-treated group was significantly decreased vs. the model group. The blood glucose, the level of FINS and HOMA-IR, TC and TG were decreased in TSG-treated group as well. Furthermore, TSG treatment significantly ameliorated lipid droplet accumulation, enhanced liver anti-oxidative response which may be associated with an increased activity of SOD and GSH-Px, and a decrease of LDLC and MDA. The autophagic cell death-associated proteins, p-AMPK, ATG12, LC3 II, and Beclin 1 were up-regulated in the TSG-treated group, while the upstream signaling pathway, PI3K/Akt and Erk, were activated.ConclusionsTSG induced liver autophagic cell death to protect liver from prediabetic injury by activating PI3K/Akt and Erk.Graphical abstract

Tetrahydroxy stilbene glycoside alleviated inflammatory damage by mitophagy via AMPK related PINK1/Parkin signaling pathway

Alzheimer’s disease (AD) is an irreversible neurodegenerative brain disorder with complex pathogenesis. The fibrillar peptide β-amyloid (Aβ) has a chief function in the pathogenesis of AD. Emerging evidence has indicated that there is a tight relationship between inflammation, mitochondrial dysfunction and Aβ formation. 2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-glucoside (TSG) is one of the main active components extracted from Polygonum multiflorum. Recent research corroborated the beneficial roles of TSG in alleviating the learning and memory of AD models. Unfortunately, the underlying mechanism of TSG remains poorly elucidated. The purpose of the present study was to investigate the effects of TSG on LPS/ATP and Aβ25-35-induced inflammation in microglia and neurons and its underlying molecular mechanisms. Our results found that treatment with TSG significantly attenuated the secretion of inflammatory cytokines, reduced NLRP3 inflammasome, and regulated mitophagy. TSG efficiently alleviated LPS-induced inflammatory response by inhibiting the NLRP3 signaling pathway both in microglia and neuron. Meanwhile, TSG promoted autophagy involved in the AMPK/PINK1/Parkin signaling pathway, which may contribute to the protective activity. Additional mechanistic investigations to evaluate the dependence of the neuroprotective role of TSG on PINK1 revealed that a lack of PINK1 inhibited autophagy, especially mitophagy in microglia. Importantly, knockdown of PINK1 or Parkin by siRNA or CRISPR/Cas9 system abolished the protective effects of TSG. In conclusion, these phenomena suggested that TSG prevented LPS/ATP and Aβ-induced inflammation via AMPK/PINK1/Parkin-dependent enhancement of mitophagy. We found the neuroprotective effect of TSG, suggesting it may be beneficial for AD prevention and treatment by suppressing the activation of inflammation.

2,3,5,4′-Tetrahydroxystilbene-2-O-β-d-glucoside alleviated the acute hepatotoxicity and DNA damage in diethylnitrosamine-contaminated mice

Aims2,3,5,4′-Tetrahydroxystilbene-2-O-β-d-glucoside (TSG) is the key bioactive ingredient extracted from Polygonum multiflorum Thumb. Pharmacological studies suggest that it exerts numerous biological effects, including anti-oxidant, anti-aging, and anti-inflammation. This study aimed at investigating the effect of TSG on diethylnitrosamine (DEN)-induced acute hepatotoxicity and DNA damage. Main methodsFifty male C57BL/6 mice were randomly divided into 5 groups (n = 10 each): control, DEN, DEN+TSG (low), DEN+TSG (high) and TSG (high) groups. DEN (100 mg/kg) was injected intraperitoneally (i.p.) alone or with TSG (30 or 60 mg/kg, i.p.) for 5 consecutive days. Key findingsTSG inhibited liver injury and inflammatory cell infiltration in DEN-treated mice. It also attenuated DEN-induced accumulation of reactive oxygen species (ROS), proinflammatory cytokines, and DNA damage. Moreover, TSG promoted the expression of nuclear erythroid 2-related factor 2 (Nrf2) target antioxidant genes by enhancing Nrf2 protein phosphorylation and nuclear translocation. As major phase I detoxification enzymes, cytochrome P450 family 2 subfamily E member 1 (CYP2E1) and cytochrome P450 1 subfamily A member 1 (CYP1A1) are responsible for the metabolic activation of DEN. We found that TSG administration inhibited CYP2E1 and CYP1A1 induction in DEN-treated mice. SignificanceThese results indicate that TSG can alleviate DEN-induced acute hepatotoxicity by modulating the Nrf2-related antioxidant system and metabolic activation of DEN. Therefore, TSG might be a promising medication for DEN-induced liver injury treatment.

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.

2, 3, 4', 5-tetrahydroxystilbene-2-0-β-d Glycoside Attenuates Age- and Diet-Associated Non-Alcoholic Steatohepatitis and Atherosclerosis in LDL Receptor Knockout Mice and Its Possible Mechanisms.

The compound, 2,3,5,4′-tetrahydroxystilbene-2-O-β-d-glucoside (TSG), a primary bioactive polyphenolic component of Polygonum multiflorum exerts numerous pharmacological activities. However, its protective effect against non-alcoholic steatohepatitis (NASH), in the context of metabolic syndrome, remains poorly understood. The aim of the present study is to evaluate the effects of TSG treatment on middle-aged (12-mo-old) male LDLr−/− mice, which were fed a high fat diet for 12 weeks to induce metabolic syndrome and NASH. At the end of the experiment, the blood samples of mice were collected for determination of metabolic parameters. Liver and aorta tissues were collected for analysis, such as histology, immunofluorescence, hepatic lipid content, real-time PCR, and western blot. Our data show that TSG treatment improved the different aspects of NASH (steatosis, inflammation, and fibrosis) and atherosclerosis, as well as some of the metabolic basal characteristics. These modulatory effects of TSG are mediated, at least in part, through regulating key regulators of lipid metabolism (SREBP1c, PPARα and their target genes, ABCG5 and CYP7A1), inflammation (CD68, TNF-α, IL-6 and ICAM), fibrosis (α-SMA and TNFβ) and oxidative stress (NADPH-oxidase 2/4, CYP2E1 and antioxidant enzymes). These results suggest that TSG may be a promising candidate for preventing and treating the progression of NASH.

2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-glucoside eliminates ischemia/reperfusion injury-induced H9c2 cardiomyocytes apoptosis involving in Bcl-2, Bax, caspase-3, and Akt activation.

This study was designed to explore the protective effect of 2,3,5,4'-tetrahydroxystilbene-2-O-β-d-glucoside (TSG) against ischemia/reperfusion (I/R) injury-induced cardiomyocytes apoptosis. The H9c2 cell I/R injury model was induced by simultaneous shortage of nutrients and oxygen. TSG administration (0.10, 0.25, and 0.50 mM) was performed before and during I/R stimulation. Cell apoptosis was evaluated using terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Expression of cell-related proteins was detected to assess the effect of TSG on cell apoptosis. I/R injury induced significant cell apoptosis. Significantly decreased Bcl-2 and increased Bax, caspase-3, and p-Akt expression ( P < 0.01) was detected in the cell model of I/R injury. In contrast, TSG administration eliminated all the changes induced by I/R injury in a dose-dependent manner. Compared with the H9c2 cell model of I/R injury, the H9c2 cells treated with 0.50 mM TSG showed the lowest cell apoptosis percentage, the highest expression of Bcl-2, and the lowest expression of Bax, caspase-3, and p-Akt ( P < 0.01). We confirmed that the protective effect of TSG against I/R injury-induced cell apoptosis in H9c2 in vitro was associated with the Bcl-2/Bax ratio, caspase-3, and Akt activation.

The Protective Effects of 2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-Glucoside in the OVA-Induced Asthma Mice Model.

Asthma is an inflammatory disease caused by an imbalance of Th1 and Th2 cells. In general, asthma is characterized by a stronger Th2 response. Most conventional asthma treatment focuses on improving airway flow or suppression of airway inflammation. To reduce the side effects of currently used asthma medicines, we have conducted studies on natural products that have no side effects. 2,3,5,4′-tetrahydroxystilbene-2-O-β-d-glucoside (TSG), the main compound of Polygonum multiflorum (PM), has various biological activities, including anti-inflammation and anti-oxidation activities. However, the effect of TSG on asthma has not been studied yet. We examined the effects of TSG on Th2 immune responses using an OVA-induced asthma animal model. OVA-sensitized mice were treated with TSG. 24 h after the last intranasal challenge, airway hyperresponsiveness (AHR) was measured or serum and bronchoalveolar lavage fluid (BALF) were harvested. We measured typical Th1 and Th2 cytokines in serum and BALF. As a result, TSG suppressed Th2 responses, as shown by the lower levels of IL-4, IL-5, total IgE, OVA-specific IgE, and OVA-specific IgG1. On the other hand, TSG increased Th1 responses, as shown by the levels of IFN-gamma. Collectively, these results confirm the potential of TSG for asthma treatment through modulation of inflammatory responses. Considering that the cytotoxic effect of PM extract is due to the cis isomer of TSG, if the effect of TSG on asthma treatment is found to be non-toxic in clinical trials, it would be more effective to use it as a purified component than PM extract as an asthma treatment agent.

Protective Effects of 2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-glucoside on Ovariectomy Induced Osteoporosis Mouse Model.

2,3,5,4′-Tetrahydroxystilbene-2-O-β-d-glucoside (TSG), an active polyphenolic component of Polygonum multiflorum, exhibits many pharmacological activities including antioxidant, anti-inflammation, and anti-aging effects. A previous study demonstrated that TSG protected MC3T3-E1 cells from hydrogen peroxide (H2O2) induced cell damage and the inhibition of osteoblastic differentiation. However, no studies have investigated the prevention of ovariectomy-induced bone loss in mice. Therefore, we investigated the effects of TSG on bone loss in ovariectomized mice (OVX). Treatment with TSG (1 and 3 μg/g; i.p.) for six weeks positively affected body weight, uterine weight, organ weight, bone length, and weight change because of estrogen deficiency. The levels of the serum biochemical markers of calcium (Ca), inorganic phosphorus (IP), alkaline phosphatase (ALP), and total cholesterol (TCHO) decreased in the TSG-treated mice when compared with the OVX mice. Additionally, the serum bone alkaline phosphatase (BALP) levels in the TSG-treated OVX mice were significantly increased compared with the OVX mice, while the tartrate-resistant acid phosphatase (TRAP) activity was significantly reduced. Furthermore, the OVX mice treated with TSG showed a significantly reduced bone loss compared to the untreated OVX mice upon micro-computed tomography (CT) analysis. Consequently, bone destruction in osteoporotic mice as a result of ovariectomy was inhibited by the administration of TSG. These findings indicate that TSG effectively prevents bone loss in OVX mice; therefore, it can be considered as a potential therapeutic for the treatment of postmenopausal osteoporosis.

2,3,5,4'-Tetrahydroxystilbene-2-O-β-glucoside potentiates self-renewal of human dental pulp stem cells via the AMPK/ERK/SIRT1 axis.

To evaluate the effect of 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (THSG) on cell proliferation and examine the mechanisms of THSG-enhanced proliferative potential in human dental pulp stem cells (hDPSC). After treatment with THSG, hDPSC were collected. Cell viability was determined by MTS assay, while messenger RNA (mRNA) expressions of proliferation and stem cell markers were analyzed using real-time PCR. Flow cytometry was also conducted to analysis protein expression of stem cell markers. A colony-forming unit assay of hDPSC was carried out. Cellular telomerase activity was also identified using real-time PCR. In addition, proliferation-related proteins involved in the effects of THSG on hDPSC were analyzed by Western blotting. Data were analyzed using one-way analysis of variance and two-tailed Student's t-test. Cell viability, colony-forming rates and telomerase activities of hDPSCs were enhanced after THSG treatment. mRNA expressions of proliferation markers (including expressions of NAD+-dependent histone deacetylase sirtuin 1 (SIRT1), proliferating cell nuclear antigen (PCNA), cyclin D1 and ribonucleotide reductase subunit M2 (RRM2)) increased significantly after THSG treatment (P<0.05). Treatment with THSG for 3h significantly augmented SIRT1 protein expression (P<0.05). Furthermore, activities of proliferation-related proteins (including AMP-activated protein kinase (AMPK) and extracellular signal-regulated kinase (ERK) had also significantly increased at 3h (P<0.05). After THSG treatment, increased gene and protein expressions of pluripotent-like stem cell markers (including NANOG, OCT4, and SOX2) were observed. 2,3,5,4'-Tetrahydroxystilbene-2-O-β-glucoside treatment enhanced the renewal ability and proliferative potential of hDPSCs via the AMPK/ERK/SIRT1 axis, which may provide a novel autogenic cell-based therapeutic strategy in regenerative dentistry.

Anti-amyloidgenic and neurotrophic effects of tetrahydroxystilbene glucoside on a chronic mitochondrial dysfunction rat model induced by sodium azide.

Alzheimer's disease (AD) is an irreversible neurodegenerative brain disorder with complex pathogenesis. Emerging evidence indicates that there is a tight relationship between mitochondrial dysfunction and β-amyloid (Aβ) formation. 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucoside (TSG) is one of the main active components extracted from Polygonum multiflorum. The purpose of the present study was to investigate the effects of TSG on Aβ production and neurotrophins in the brains of rats by using a mitochondrial dysfunction rat model induced by sodium azide (NaN3), an inhibitor of mitochondrial cytochrome c oxidase (COX). NaN3 was administered to rats by continuous subcutaneous infusion for 28days via implanted osmotic minipumps to establish the animal model. TSG was intragastrically administered starting 24h after the operation. The activity of mitochondrial COX was measured by a biochemical method. The content of Aβ 1-42 was detected by ELISA. The expression of neurotrophic factors was determined by Western blot and immunohistochemistry. The results showed that NaN3 infusion for 28days induced a decrease in mitochondrial COX activity, an increase in Aβ 1-42 content and the expression of amyloidogenic β-amyloid precursor protein (APP), beta-site APP cleaving enzyme 1 (BACE1) and presenilin 1 (PS1), and a decline in the expression of neurotrophins in the hippocampus of rats. Intragastrical administration of TSG elevated mitochondrial COX activity, decreased Aβ 1-42 content and the expression of APP, BACE1 and PS1, and enhanced the expression of nerve growth factor, brain-derived neurotrophic factor (BDNF) and its receptor tropomyosin-related kinase B (TrkB) in the hippocampus of NaN3-infused rats. These findings suggest that TSG may be beneficial in blocking or slowing the progression of AD by enhancing mitochondrial function, decreasing Aβ production and increasing neurotrophic factors at some extent.

In Vitro and In Vivo Anti-Osteoarthritis Effects of 2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-Glucoside from Polygonum Multiflorum.

Polygonum multiflorum Thunb. is a traditional herbal medicine that is rich in polyphenols. The major compound, 2,3,5,4′-tetrahydroxystilbene-2-O-β-d-glucoside (THSG) has many pharmacological activities, such as antioxidative and free radical-scavenging properties, and the abilities to reduce hyperlipidemia, prevent lipid peroxidation, and protect the cardiovascular system. In this study, the anti-osteoarthritis (OA) effects of THSG were explored using in vitro and in vivo models. THSG inhibited nitric oxide (NO) and prostaglandin E2 (PGE2) production and inducible NO synthase (iNOS) and cyclooxygenase-2 expressions by lipopolysaccharide-stimulated RAW 264.7 cells. On the other hand, THSG inhibited PGE2 production and iNOS and matrix metalloproteinase-13 expressions by interleukin-1β-stimulated primary rat chondrocytes. Through a mono-iodoacetate-induced rat OA model assay, THSG reduced paw edema and improved the weight-bearing distribution. Therefore, THSG has anti-inflammatory activity and could be applied as a lead compound for the development as an OA drug.

TETRAHYDROXYSTILBENE GLUCOSIDE AMELIORATES MEMORY AND MOVEMENT FUNCTIONS, PROTECTS SYNAPSES AND INHIBITS α-SYNUCLEIN AGGREGATION IN HIPPOCAMPUS AND STRIATUM IN AGED MICE

Aging is the greatest risk factor of senile neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD) and dementia of Lewy body (DLB). Synaptic dysfunction plays an important role in the progression of cognitive impairment and movement disorder among these neurodegenerative diseases. Synaptic degeneration occurs early in the progression of AD involving neocortical and limbic system circuitries. Accumulating oligomeric α-synuclein may mediate early synaptic pathology in PD and DLB by disrupting synaptic vesicles. Polygonum multiflorum has been widely used in China as an anti-aging agent since ancient times. 2,3,5,4’-Tetrahydroxystilbene-2-O-β-D-glucoside (TSG) is one of the main active component extracted from the root of Polygonum multiflorum. The purpose of this study was to investigate the effects of TSG on the memory and movement functions and its mechanisms related to synapses and a-synuclein in aged mice. The memory ability of mice was detected by step-through passive avoidance task. The movement function was measured by the pole test and rotarod test. Transmission electron microscopy was used to observe the synaptic ultrastructure. Western blotting was applied to measure the expression of synapse-related proteins and a-synuclein. Intragastrical administration of TSG for 3 months significantly improved the memory and movement functions in aged mice. TSG treatment obviously protected the synaptic ultrastructure and increased the number of synaptic connections in the hippocampal CA1 region and striatum; enhanced the expression of synaptophysin, phosphorylated synapsin I and postsynaptic density protein 95 (PSD-95), elevated phosphorylated calcium/calmodulin-dependent protein kinase II (p-CaMK II) expression, and inhibited the overexpression and aggregation of a-synuclein in the hippocampus, striatum and cerebral cortex of aged mice. TSG improved the memory and movement functions in aged mice through protecting synapses and inhibiting a-synuclein overexpression and aggregation in multiple brain regions. The results suggest that TSG may have the potential to treat Alzheimer's disease, Parkinson's disease dementia and dementia of Lewy body.

Tetrahydroxystilbene glucoside inhibits α-synuclein aggregation and apoptosis in A53T α-synuclein-transfected cells exposed to MPP.

Increasing evidence has solidified the involvement of α-synuclein (α-Syn) and neurotoxins in the pathogenesis of Parkinson's disease (PD), suggesting a combination of genetic and environmental influences. 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucoside (TSG) is one of the main active components extracted from Polygonum multiflorum. The purpose of the present study was to investigate the effects of TSG on α-Syn aggregation, mitochondrial dysfunction, oxidative stress, and apoptosis in vitro. A53T mutant α-synuclein-transfected cells (A53T AS cells) plus MPP+ exposure were used as a complex cell model of PD. The expression of proteins was determined by Western blot assay. Flow cytometry was utilized to measure mitochondrial membrane potential and apoptosis. The results showed that MPP+ exposure for 24 h induced more severe damage in A53T AS cells than in vector control cells. Pretreatment of TSG for 24 h significantly increased the cell viability; decreased lactate dehydrogenase leakage; inhibited α-Syn over-expression and aggregation; elevated mitochondrial membrane potential; decreased reactive oxygen species, Bax/Bcl-2 ratio, and caspase-3 activity; and inhibited apoptosis in A53T AS cells exposed to MPP+. These results suggest that TSG may be an attractive candidate for PD therapy.

HO-1 Is Essential for Tetrahydroxystilbene Glucoside Mediated Mitochondrial Biogenesis and Anti-Inflammation Process in LPS-Treated RAW264.7 Macrophages

2,3,5,4′-Tetrahydroxystilbene-2-O-β-D-glucoside (TSG), an important monomer extracted from Polygonum multiflorum, can prevent a number of inflammation associated chronic diseases. However, the mechanism involved in TSG inducing anti-inflammatory role remains unclear. As an inducible antioxidant enzyme, Heme oxygenase-1 (HO-1), is crucial for protecting the mammalian cells against adverse stimuli. Here, we found that the TSG treatment strongly induces the expression of HO-1 in an NRF2-depended manner. Meanwhile, TSG increased the mitochondrial mass through upregulation of the mitochondrial biogenesis activators (PGC-1α, NRF1, and TFAM) as well as the mitochondrial complex IV. Furthermore, TSG attenuated Lipopolysaccharide (LPS) mediated RAW264.7 cells activation and secretion of proinflammatory cytokines, including interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Zinc Protoporphyrin (ZnPP), a selective inhibitor of HO-1 activity, was able to attenuate TSG mediated mitochondrial biogenesis and anti-inflammatory process. Finally, we observed that LPS induced obvious mtDNA depletion and ATP deficiency, which indicated a severe damage of mitochondria. TSG restored the LPS induced mitochondrial dysfunction via activation of the mitochondrial biogenesis. ZnPP treatment markedly reversed the inhibitory effects of TSG on mitochondrial damage and oxidative stress in LPS stimulated macrophages. Taken together, these findings suggest that TSG enhances mitochondrial biogenesis and function mainly via activation the HO-1. TSG can be developed as a potential drug for treatment of inflammatory diseases.