Irina Tsoy Nizamutdinova

Metformin inhibits HMGB1 release in LPS-treated RAW 264.7 cells and increases survival rate of endotoxaemic mice

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.

The anti-diabetic effect of anthocyanins in streptozotocin-induced diabetic rats through glucose transporter 4 regulation and prevention of insulin resistance and pancreatic apoptosis.

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.

Tanshinone I suppresses growth and invasion of human breast cancer cells, MDA-MB-231, through regulation of adhesion molecules

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.

Anthocyanins from black soybean seed coats stimulate wound healing in fibroblasts and keratinocytes and prevent inflammation in endothelial cells.

Wound healing is a complex process that includes inflammation, tissue formation, and remodeling. While wound healing is accompanied by inflammatory reactions, chronic inflammation impairs acute wound healing. In this study, we investigated whether anthocyanins from black soybean seed coats could stimulate wound healing while preventing excessive inflammation. At 24h of treatment with anthocyanins, fibroblasts showed a significant increase in migration at 100 microg/mL whereas the migration of keratinocytes increased significantly at 50 and 100 microg/mL compared to control. Treatment of anthocyanins for 48 h significantly stimulated the migration of both human dermal fibroblasts and keratinocytes at 50 and 100 microg/mL concentrations. Treatment of cells with anthocyanins stimulated wound-induced VEGF production in fibroblasts and keratinocytes. However, anthocyanins inhibited ROS accumulation and VEGF production in TNF-alpha-stimulated endothelial cells. Furthermore, treatment of anthocyanins reduced, in a dose-dependent manner, the adhesion of inflammatory monocytes to endothelial cells. Anthocyanins also blocked both the translocation of nuclear factor-kappa B (NF-kappaB) p65 into the nucleus and the phosphorylation of the inhibitory factor kappaBalpha (IkappaBalpha). Thus, treatment with anthocyanins from black soybean seed coats may be a potential therapeutic strategy to promote wound healing and to prevent inflammation in a persistent inflammatory condition.

Paeonol and Paeoniflorin, the Main Active Principles of Paeonia albiflora, Protect the Heart from Myocardial Ischemia/Reperfusion Injury in Rats

The aim of this study was to investigate the effects of paeoniflorin (PF) and paeonol (PN), the main active compounds of the Paeonia albiflora Pallas, on myocardial ischemia and reperfusion (I/R)-induced injury in Sprague-Dawley rats IN VIVO. Under anesthesia, the rats were subjected to 25 min of ischemia by ligation of the left anterior descending coronary artery (LAD) followed by 6 h (Western blot analysis) or 24 h (hemodynamics and infarct size) of reperfusion. When the infarct size was measured as the percentage of the area at risk, both PF (25.0 % +/- 7.0 %) and PN (24.1 % +/- 5.5 %) significantly (P < 0.05) reduced it compared to I/R control (54.8 % +/- 2.6 %). Administration of 10 mg/kg PF or PN 1 h prior to I/R injury also resulted in a significant improvement of the hemodynamic parameters. Furthermore, both PF and PN decreased the caspase-3 and Bax expressions but up-regulated Bcl-2 in the left ventricles. The results show that both PF and PN reduced myocardial damage in rat through protection from apoptosis, suggesting that Paeonia albiflora Pallas might be useful in treating myocardial infarction.

Cryptotanshinone, a lipophilic compound of Salvia miltiorrriza root, inhibits TNF-α-induced expression of adhesion molecules in HUVEC and attenuates rat myocardial ischemia/reperfusion injury in vivo

The aim of the present study was to evaluate the protective effect of cryptotanshinone (CTS), one of active ingredients of Salvia miltiorrhiza root, on myocardial ischemia-reperfusion injury in rat due to inhibition of some inflammatory events that occur by NF-kappaB-activation during ischemia and reperfusion. Myocardial ischemia and reperfusion injury was induced by occluding the left anterior descending coronary artery for 30 min followed by either 2 h (biochemical analysis) or 24 h (myocardial function and infarct size measurement) reperfusion. CTS injected (i.v.) 10 min before ischemia and reperfusion insult. CTS significantly reduced the infarct size and improved ischemia and reperfusion-induced myocardial contractile dysfunction. Furthermore, CTS inhibited NF-kappaB translocation, expression of pro-inflammatory cytokines (TNF-alpha, IL-1beta, IL-6), neutrophil infiltration and MPO activity in ischemic myocardial tissues. CTS also significantly reduced plasma levels of TNF-alpha, IL-1beta due to ischemia and reperfusion. Interestingly, H(2)O(2)-stimulated NF-kappaB-luciferase activity and TNF-alpha-induced expression of vascular cell adhesion molecule-1 (VCAM-1) and intracellular adhesion molecule-1 (ICAM-1) expressions in human umbilical vein endothelial cells (HUVEC) were significantly inhibited by CTS. Taken together, it is concluded that CTS may attenuate ischemia and reperfusion-induced microcirculatory disturbances by inhibition of proinflammatory cytokine production, reduction of neutrophil infiltration and possibly inhibition of adhesion molecules through inhibition of NF-kappaB-activation during ischemia and reperfusion.

Hesperidin, hesperidin methyl chalone and phellopterin from Poncirus trifoliata (Rutaceae) differentially regulate the expression of adhesion molecules in tumor necrosis factor-α-stimulated human umbilical vein endothelial cells

The fruits of Poncirus trifoliata (L.) are widely used in Oriental medicine to treat allergic inflammation. Recently, several active compounds including hesperidin, hesperidin methyl chalone and phellopterin from P. trifoliata (Rutaceae) were isolated and characterized. The goal of this study was to investigate the differential effect of hesperidin, hesperidin methyl chalone and phellopterin derived from P. trifoliata (Rutaceae) on the induction of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by TNF-alpha and the possible molecular mechanisms by which they differentially regulate ICAM-1 and VCAM-1 expressions. Stimulation of human umbilical vein endothelial cells (HUVECs) with TNF-alpha resulted in the increase of ICAM-1 and VCAM-1 expressions, while pretreatment with the three components completely inhibited VCAM-1 expression in a dose-dependent manner but had no effect on ICAM-1 expression. All three compounds failed to block TNF-alpha-induced phosphorylation of ERK1/2, which is involved in regulating ICAM-1 production by TNF-alpha. Furthermore, they efficiently inhibited the phosphorylation of Akt and PKC, suggesting that Akt or PKC pathways are an important target by which these compounds regulate TNF-alpha-induced VCAM-1 but not ICAM-1. Additionally, treatment with these chemicals also inhibited U937 monocyte adhesion to HUVECs stimulated with TNF-alpha. Interestingly, the inhibitory effect of hesperidin, hesperidin methyl chalone and phellopterin on monocyte adhesion to HUVECs was recapitulated by transfecting cells with VCAM-1 siRNA. Taken together, hesperidin, hesperidin methyl chalone and phellopterin reduce TNF-alpha-induced VCAM-1 expression through regulation of the Akt and PKC pathway, which contributes to inhibit the adhesion of monocytes to endothelium.

Anthocyanins from black soybean seed coats preferentially inhibit TNF-α-mediated induction of VCAM-1 over ICAM-1 through the Regulation of GATAs and IRF-1.

Adhesion molecules have a key role in pathological inflammation. Thus, we investigated the effect of anthocyanins on the induction of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) by TNF-alpha and the possible molecular mechanisms by which anthocyanins differentially regulate ICAM-1 and VCAM-1 expression. Stimulation of cells with TNF-alpha increased ICAM-1 and VCAM-1 expression, and pretreatment with anthocyanins inhibited VCAM-1 expression, but not ICAM-1 expression. We found that IRF-1 and GATAs, especially GATA-4 and -6, were involved in the TNF-alpha-mediated expression of VCAM-1 but not ICAM-1, and anthocyanins decreased nuclear levels of GATA-4 and GATA-6 as well as IRF-1. Moreover, pretreatment with a Jak/STAT inhibitor decreased TNF-alpha-induced VCAM-1 expression and nuclear GATA-4, GATA-6, and IRF-1 levels. Furthermore, anthocyanins efficiently inhibited the phosphorylation of STAT-3. This suggests that anthocyanins differentially regulate TNF-alpha-mediated expression of VCAM-1 and ICAM-1 through modulation of the GATA and IRF-1 binding activity via Jak/STAT-3 activation.

Carbon monoxide from CORM-2 reduces HMGB1 release through regulation of IFN-β/JAK2/STAT-1/INOS/NO signaling but not COX-2 in TLR-activated macrophages.

Reduction of high-mobility group box 1 (HMGB1) and NO levels may be important therapeutic strategy for treatment of sepsis. Recently, we found that carbon monoxide (CO) can reduce HMGB1 levels in septic animal models. Here, we tried to elucidate the molecular machinery of how CO inhibits HMGB1 release in toll-like receptor (TLR)-activated macrophages. Carbon monoxide-releasing molecule 2 (CORM-2) specifically inhibited the expression of iNOS (NO), but not of cyclooxygenase 2 (COX-2) (PGE2) in RAW 264.7 cells activated either by peptidoglycan (TLR-2 agonist), polyinosinic-polycytidylic acid (TLR-3 agonist), or LPS (TLR-4 agonist); this inhibition seemed to be mediated via the JAK2/STAT1 pathway. Treatment with neutralizing antibody to IFN-&bgr;, a JAK2 inhibitor (AG490), or a STAT1 inhibitor (fludarabine) selectively inhibited iNOS, but not COX-2 in this system. Moreover, deletion of STAT1 by siRNA also showed preferential inhibition of iNOS but not COX-2 in LPS-treated cells. Carbon monoxide-releasing molecule 2 reduced IFN-&bgr; production and phosphorylation of JAK2 and STAT1 in LPS-activated RAW264.7 cells. Carbon monoxide-releasing molecule 2 failed to inhibit iNOS and HMGB1 levels in the presence of recombinant IFN-&bgr; and NO donor (NOC-18), respectively. Finally, plasma levels of HMGB1 and iNOS protein expression in lung tissues of cecal ligation and puncture-induced septic mice were decreased in the presence of CORM-2. Taken together, it is concluded that CO selectively inhibits iNOS over COX-2, at least through IFN&bgr;/JAK2/STAT1 signals, and this regulation plays an important role in the CORM-2-mediated inhibitory effect on HMGB1 release in macrophages.

Bisacurone inhibits adhesion of inflammatory monocytes or cancer cells to endothelial cells through down-regulation of VCAM-1 expression.

Bisacurone, one of the active compounds of the traditionally used indigenous herb Curcuma longa Linne (Zingiberaceae), has anti-oxidant, anti-inflammatory, and anti-metastatic activities. We studied how the level of vascular cell adhesion molecule-1 (VCAM-1), one of the key molecules in the development of atherosclerosis as well as carcinogenesis and metastasis, might be affected by bisacurone in tumor necrosis factor-alpha (TNF-alpha)-activated human umbilical vein endothelial cells (HUVECs). Bisacurone dose-dependently inhibited TNF-alpha-mediated expression of VCAM-1. It showed significant suppressive effect on ROS generation in response to TNF-alpha stimulation and it blocked nuclear factor-kappa B (NF-kappaB) p65 translocation into the nucleus and phosphorylation of inhibitory factor kappaBalpha (IkappaBalpha). It also inhibited phosphorylation of Akt and PKC, which are upstream in the regulation of VCAM-1 by TNF-alpha. Furthermore, bisacurone decreased U937 monocyte and human oral cancer cell (Hep-2, QLL-I, SCC-15) adhesion to HUVECs stimulated by TNF-alpha, suggesting that it may inhibit the binding of these cells by regulating the expression of critical adhesion molecules by TNF-alpha. Thus, bisacurone may be beneficial in the treatment of inflammatory diseases, such as atherosclerosis, where inflammatory monocytes are involved in their pathology, and, moreover, in the development of tumors.