Hyperglycemia, abnormal lipid and antioxidant profiles are the most usual complications in diabetes mellitus. Thus, in this study, we investigated the anti-diabetic and anti-oxidative effects of anthocyanins (ANT) from black soybean seed coats in streptozotocin (STZ)-induced diabetic rats. The administration of ANT markedly decreased glucose levels and improved heart hemodynamic function (left ventricular end diastolic pressure, +/-dp/dt parameters). ANT not only enhanced STZ-mediated insulin level decreases, but also decreased the triglyceride levels induced by STZ injection in serum. Diabetic rats exhibited a lower expression of glucose transporter 4 proteins in the membrane fractions of heart and skeletal muscle tissues, which was enhanced by ANT. In addition, ANT activated insulin receptor phosphorylation, suggesting an increased utilization of glucose by tissues. Moreover, ANT protected pancreatic tissue from STZ-induced apoptosis through regulation of caspase-3, Bax, and Bcl-2 proteins. Furthermore, ANT significantly suppressed malondialdehyde levels and restored superoxide dismutase and catalase activities in diabetic rats. Interestingly, the observed effects of ANT were superior to those of glibenclamide. Taken together, ANT from black soybean seed coat have anti-diabetic effects that are due, in part, to the regulation of glucose transporter 4 and prevention of insulin resistance and pancreatic apoptosis, suggesting a possible use as a drug to regulate diabetes.

We examined our hypothesis that heme-oxygenase-1 (HO-1)-derived carbon monoxide (CO) inhibits the release of highmobility group box 1 (HMGB1) in RAW264.7 cells activated with lipopolysaccharide (LPS) in vitro and in LPS-or cecal ligation and puncture (CLP)-induced septic mice in vivo, so that HO-1 induction or CO improves survival of sepsis in rodents. We found that pretreatment with HO-1 inducers (hemin, cobalt protoporphyrin IX) or transfection of HO-1 significantly inhibited HMGB1 release, which was blocked by HO-1 small interfering RNA, in cells activated by LPS. Carbon monoxide-releasing molecule 2 (CORM-2) but not bilirubin or deferoxamine inhibited HMGB1 release in LPS-activated macrophages. Oxyhemoglobin reversed the effect of HO-1 inducers on HMGB1 release. Translocation of HMGB1 from nucleus to cytosol was significantly inhibited by HO-1 inducers, CORM-2, or HO-1 transfection. Neutralizing antibodies to tumor necrosis factor (TNF)-␣, interleukin (IL)-1␤, interferon-␤, and N -nitro-L-arginine methyl ester hydrochloride but not N-[2-(cyclohexyloxyl)-4-nitrophenyl]-methane sulfonamide (NS-398) significantly inhibited HMGB1 release in LPS-activated cells. Production of TNF-␣, IL-1␤, and IFN-␤ was significantly reduced by pretreatment of HO-1 inducers, CORM-2, or HO-1 transfection in LPS-activated cells. Plasma levels of HMGB1 in mice challenged with LPS or CLP were significantly reduced by the administration of HO-1 inducers or CORM-2, which was accompanied by either reduction (pretreatment) or no change (delayed administration) of serum TNF-␣ and IL-1␤ levels. Regardless of pretreatment or delayed administration, CORM-2 and hemin rescued mice from lethal endotoxemia and sepsis induced by LPS or CLP. Taken together, we concluded that HO-1-derived CO reduces HMGB1 release in LPS-activated cells and LPS-or CLP-induced animal model of sepsis.Sepsis is defined as a systemic inflammatory response syndrome from a microbial infection that results from excessive stimulation of the host immune system by pathogen components to produce various proinflammatory cytokines, and their overproduction causes systemic inflammation that can lead to the lethal multiple organ damage (Oberholzer et al., 2001). High-mobility group box 1 (HMGB1) is a chromatin-binding protein that participates in maintaining nucleosome structure and regulation of gene transcription (Landsman and Bustin, 1993). Various evidence indicated that HMGB1 is a necessary and sufficient late mediator of severe sepsis (Wang et al., 1999;Yang et al., 2004). Once released, HMGB1 can bind to cell-surface receptors, such as the receptor for advanced glycation end products and Toll-like receptors 2 and 4, and mediate various cellular responses, chemotactic cell movement, and release of proinflammatory Article, publication date, and citation information can be found at http://molpharm.aspetjournals.org. doi:10.1124/mol.109.055137.ABBREVIATIONS: HMGB1, high-mobility group box 1; HO-1, heme-oxygenase-1; CORM-2, carbon monoxide-releasing molecule II; LPS, lip...

BACKGROUND AND PURPOSE Recently, metformin, a well‐known anti‐diabetic drug, has been shown to possess anti‐inflammatory activities. This study investigated the effect of metformin on the expression of pro‐inflammatory cytokines including high mobility group box 1 (HMGB1) in lipopolysaccharide (LPS)‐treated animals and cells. EXPERIMENTAL APPROACH We investigated whether metformin inhibits the release of HMGB1 in LPS‐treated RAW 264.7 cells and increases survival rate in endotoxaemic mice (lethal endotoxaemia was induced by an i.p. injection of LPS). This was achieved by a range of techniques including Western blotting, enzyme‐linked immunosorbent assay, specific pharmacological inhibitors, knock out of α1‐subunit of AMP‐activated protein kinase (AMPK) and recombinant HMGB1. KEY RESULTS Both pre‐ and post‐treatment with metformin significantly improved survival of animals during lethal endotoxaemia (survival rate was monitored up to 2 weeks), decreased serum levels of tumour necrosis factor‐alpha (TNF‐α), interleukin‐1β, HMGB1 expression and myeloperoxidase activity in lungs. However, metformin failed to improve survival in endotoxaemic animals that had additionally been treated with recombinant HMGB1. In an in vitro study, metformin dose‐dependently inhibited production of pro‐inflammatory cytokines and HMGB1 release. Metformin activated AMPK by its phosphorylation. Compound C (pharmacological inhibitor of AMPK) and siAMPKα1 reversed the anti‐inflammatory effect of metformin in LPS‐treated cells. CONCLUSIONS AND IMPLICATIONS Our data indicate that metformin significantly attenuates the pro‐inflammatory response induced by LPS both in vivo and in vitro. Metformin improved survival in a mouse model of lethal endotoxaemia by inhibiting HMGB1 release. AMPK activation was implicated as one of the mechanisms contributing to this inhibition of HMGB1 secretion.

The role of cell adhesion molecules has been studied extensively in the process of inflammation, and these molecules are critical components of carcinogenesis and cancer metastasis. This study investigated the effect of tanshinone I derived from the traditional herbal medicine, Salvia miltiorrhiza Bunge, on the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in tumor necrosis factor-alpha (TNF-alpha)-stimulated endothelial cells. Furthermore, this study investigated the effect of tanshinone I on cancer growth, invasion and angiogenesis on human breast cancer cells MDA-MB-231, both in vitro and in vivo. Tanshinone I dose dependently inhibited ICAM-1 and VCAM-1 expressions in human umbilical vein endothelial cells (HUVECs) that were stimulated with TNF-alpha for 6 h. Pretreatment with tanshinone I significantly reduced adhesion of either monocyte U937 or MDA-MB-231 cells to HUVECs. Interestingly, the inhibitory effect of tanshinone I on monocyte and cancer cell adhesion to HUVECs was mimicked by transfection with ICAM-1 and VCAM-1 small interfering RNA. In addition, tanshinone I effectively inhibited TNF-alpha-induced production of vascular endothelial growth factor (VEGF) and VEGF-mediated tube formation in HUVECs. Tanshinone I also inhibited TNF-alpha-induced VEGF production in MDA-MB-231 cells and migration of MDA-MB-231 cells through extracellular matrix. Additionally, reduction of tumor mass volume and decrease of metastasis incidents by tanshinone I were observed in vivo. In conclusion, this study provides a potential mechanism for the anticancer effect of tanshinone I on breast cancer cells, suggesting that tanshinone I may serve as an effective drug for the treatment of breast cancer.

Abstract. Danshen (Salvia miltiorrhiza Bunge) is a herb that has been widely and successfully used for treating inflammatory diseases in clinics in Asia. The relatively abundant tanshinones, tanshinone I, tanshinone IIA, cryptotanshinone, and dihydrotanshinone, have been isolated from Danshen. These tanshinones are the major diterpenes isolated from Danshen, and show cytotoxic effects on cell lines derived from human carcinomas of the colon, ovary, lung, mouth, and breast. Recently, anti-cancer activities of tanshinone IIA have been reported, which suggest that the structurally similar tanshinone I may possess similar cytotoxic effects on tumor cells. We investigated the effect of tanshinone I on the induction of apoptosis in human breast cancer cells (MCF-7 and MDA-MB-231) in vitro. Tanshinone I inhibited cell proliferation of MCF-7 and MDA-MB-231 cells in a doseand time-dependent manner, as assayed by MTT. In addition, TUNEL assay and flow cytometry showed that tanshinone I significantly induced apoptosis in MCF-7 and MDA-MB-231 cells. The induction of apoptotic cell death was mediated by the activation of caspase 3, the downregulation of the level of the anti-apoptotic protein, Bcl-2, and the upregulation of the level of the pro-apoptotic protein, Bax. Taken together, these results reveal a potential mechanism for the anti-cancer effect of tanshinone I on human breast cancer cells, and suggest that tanshinone I may serve as an effective adjunctive reagent in the treatment of human breast cancer.