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PubMed2004

Studies on the spectroscopic behavior of cryptotanshinone, tanshinone IIA, and tanshinone I.

A comparative study on the spectroscopic behavior of cryptotanshinone (CTan), tanshinone IIA (Tan IIA), and tanshinone I (Tan I) has been investigated, including UV-Vis absorption, low temperature phosphorescence (LTP), low temperature fluorescence (LTF), paper substrate-room temperature phosphorescence (PS-RTP), paper substrate-room temperature fluorescence (PS-RTF) and fluorescence in liquid (LF). The effect of pH on the luminescence intensity is discussed. Lifetime and polarization of the LTP and RTP have been examined with phosphorescence lifetime in the range of 0.6-0.9s and polarization in the range of 0.10-0.27. Analytical characteristics of LF, PS-RTF and PS-RTP of CTan, Tan IIA, and Tan I have been studied.

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PubMed2005

Potential anticancer activity of tanshinone IIA against human breast cancer.

Tanshinone IIA is a derivative of phenanthrene-quinone isolated from Danshen, a widely used Chinese herbal medicine. It has antioxidant properties and cytotoxic activity against multiple human cancer cell lines, inducing apoptosis and differentiation of some human cancer cell lines. Our purpose was to confirm its anticancer activity on human breast cancer in vitro and in vivo and to elucidate the mechanism of its activity. Human breast cancer cells were tested in vitro for cytotoxicity, colony formation inhibition, BrdU incorporation and gene expression profiling after treatment with tanshinone IIA. Seven nude mice bearing human breast infiltrating duct carcinoma orthotopically were tested for anticancer activity and expression of caspase-3 in vivo by s.c. injection of tanshinone IIA at a dose of 30 mg/kg 3 times/week for 10 weeks. Tanshinone IIA demonstrated a dose- and time-dependent inhibitory effect on cell growth (IC50 = 0.25 microg/ml), and it significantly inhibited colony formation and BrdU incorporation of human breast cancer cells. Oligonucleotide microarray analysis identified 41 upregulated (1.22%) and 24 downregulated (0.71%) genes after tanshinone IIA treatment. Upregulated genes were involved predominantly in cycle regulation, cell proliferation, apoptosis, signal transduction and transcriptional regulation; and downregulated genes were associated mainly with apoptosis and extracellular matrix/adhesion molecules. A 44.91% tumor mass volume reduction and significant increase of casepase-3 protein expression were observed in vivo. Our findings suggest that tanshinone IIA might have potential anticancer activity on both ER-positive and -negative breast cancers, which could be attributed in part to its inhibition of proliferation and apoptosis induction of cancer cells through upregulation and downregulation of multiple genes involved in cell cycle regulation, cell proliferation, apoptosis, signal transduction, transcriptional regulation, angiogenesis, invasive potential and metastatic potential of cancer cells. ADPRTL1 might be the main target at which tanshinone IIA acted.

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PubMed2006

Growth inhibition and induction of apoptosis and differentiation of tanshinone IIA in human glioma cells.

Tanshinone IIA is a derivative of phenanthrene-quinone isolated from Danshen, a widely used Chinese herbal medicine. It has antioxidant properties, cytotoxic activities against multiple human cancer cells, inducing apoptosis and differentiation of some human cancer cells. The purpose of this study is to confirm its anticancer activity on human glioma cells, and to elucidate mechanism of its activity. Human glioma cells were tested in vitro for cytotoxicity, colony formation inhibition, BrdU incorporation after treatment with tanshinone IIA. Its effect of apoptosis induction was detected through EB/AO staining, cell cycle analysis and the expressions of ADPRTL1 and CYP1A1 genes, the differentiation induction effect was investigated through morphology, mRNA and protein expressions of GFAP and nestin genes by RT-PCR and immunocytochemistry. Tanshinone IIA demonstrated a dose- and time-dependent inhibitory effect on cell growth, IC(50) was 100 ng/ml, and it significantly inhibited colony formation and BrdU incorporation of human glioma cells. After treatment with 25-100 ng/ml of tanshinone IIA, the apoptotic cells increased significantly (P < 0.01), the cells in G(0)/G(1) phase increased (P < 0.01), and decreased in S phase, ADPRTL1 and CYP1A1 mRNA expression increased 1-2 folds. The cells treated with 100 ng/ml tanshinone IIA demonstrated astrocytes or neuron-like morphology, GFAP mRNA and protein expressions increased, nestin mRNA and protein expressions decreased significantly. The findings in this study suggested that tanshinone IIA exhibited strong effects on growth inhibition and induction of apoptosis and differentiation in human glioma cells. It might serve as a novel promising differentiation-inducing and/or therapeutic agent for human gliomas, and need to be investigated further.

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PubMed2005

Partial neuroprotective effect of pretreatment with tanshinone IIA on neonatal hypoxia-ischemia brain damage.

Tanshinone IIA is a compound purified from the Chinese herb Danshen (Radix Salviae Miltiorrhiza Bge). The neuroprotective effect of tanshinone IIA was investigated in a neonatal rat model of hypoxia-ischemia brain damage. Hypoxia-ischemia encephalopathy was induced in rats at day 7 of postnatal age by ligation of the right common carotid artery, followed by 2 h of hypoxia. Tanshinone IIA (10 mg/kg, i.p.) was injected daily from day 2 before surgery for 9 or 16 d. Our results demonstrated significant and sustained brain damage in the hypoxia-ischemia- and vehicle-treated groups at 1 and 3 wk after surgery. Treatment with tanshinone IIA significantly reduced the severity of brain injury, as indicated by the increase in ipsilateral brain weight and neuron density, compared with those of sham-operated animals. The recovery of sensorimotor function and histology was observed in animals that received tanshinone IIA. The plasma of tanshinone IIA-treated rats exhibited higher antioxidant activities, as reflected by the oxygen radical absorbance capacity assay, compared with the vehicle-treated rats. In the neural progenitor cell line C17.2 that was subjected to 2,2'-azobis (2-amidino propane hydrochloride)-induced oxidative stress, tanshinone IIA increased cell viability and protected against mitochondrial damage (JC-1 assay). Our results suggest that tanshinone IIA has antioxidative activities and that treatment that is started before a hypoxic-ischemic insult is partially neuroprotective. Further studies are required to elucidate whether rescue treatment with tanshinone IIA is effective and to determine whether its protective effect is also associated with secondary cooling of the brain.

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PubMed2003

Diterpene quinone tanshinone IIA selectively inhibits mouse and human cytochrome p4501A2.

1. Tanshinone IIA is the main active diterpene quinone in the herbal medicine Salvia miltiorrhiza. In untreated mouse liver microsomes, tanshinone IIA selectively inhibited 7-ethoxyresorufin O-deethylation (EROD) and 7-methoxyresorufin O-demethylation (MROD) activities without affecting the oxidation of benzo(a)pyrene, tolbutamide, N-nitrosodimethylamine and nifedipine. Tanshinone IIA was a competitive inhibitor of MROD activity with a K(i) of 7.2 +/- 0.7 nM. 2. In 3-methylcholanthrene-treated mouse liver microsomes, tanshinone IIA and two minor tanshinones, tanshinone I and cryptotanshinone, inhibited liver microsomal MROD activity without affecting EROD and benzo(a)pyrene hydroxylation activities at the concentrations up to 1 microM. Tanshinone IIA induced a type I binding spectrum with a spectral dissociation constant K(s) of 2.3 +/-0.8 microM without cooperativity. 3. In human liver microsomes, tanshinone IIA decreased EROD and MROD activities without affecting the oxidation of benzo(a)pyrene, tolbutamide, chlorzoxazone and nifedipine. 4. In Escherichia coli membranes expressing bicistronic human CYP1A enzymes, tanshinone IIA inhibited EROD activity of CYP1A1 with an IC(50) 48 times higher than that for CYP1A2. Tanshinone I and cryptotanshinone had the same IC(50) ratio (1A1/1A2) of 4. 5. The results indicate that tanshinone represents a new group of CYP1A inhibitors, and tanshinone IIA had the highest selectivity in inhibition of CYP1A2.

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PubMed2006

Induction of apoptosis and inhibition of cell adhesive and invasive effects by tanshinone IIA in acute promyelocytic leukemia cells in vitro.

Tanshinone IIA, a diterpene quinone extracted from the traditional herbal medicine, Salvia miltiorrhiza Bunge, is used widely and successfully in clinics in China for treating inflammatory diseases. Recently tanshinone IIA has been reported to have apoptosis inducing effects on a large variety of cancer cells. In this study, the anti-proliferation and apoptosis inducing effects of tanshinone IIA as well as its influence on cell adhesion to and invasion through the extracellular matrix (ECM) on acute promyelocytic leukemia (APL) NB4 cells in vitro were studied. Cell proliferation was assessed by MTT assay, cell apoptosis was observed by Hoechst 33258 staining and flow cytometry (FCM); The variation of caspase-3 and apoptotic related genes were assayed by Western blotting, cell mitochondrial membrane potential as well as cell adhesive and invasive effects were also investigated by using standard methods. The results showed that tanshinone IIA exhibited induction of apoptosis by activation of caspase-3, downregulation of anti-apoptotic protein bcl-2 and bcl-xl and upregulation of pro-apoptotic protein bax, as well as disruption of the mitochondrial membrane potential. Furthermore, treatment by tanshinone IIA could reduce cell adhesion to and invasion through ECM in leukemia NB4 cells. These data provide a potential mechanism for tanshinone IIA-induced apoptosis and cell growth inhibition in leukemia NB4 cells, suggesting that tanshinone IIA may serve as an effective adjunctive reagent for the treatment of APL.

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PubMed2006

Characterization of metabolites of tanshinone IIA in rats by liquid chromatography/tandem mass spectrometry.

The metabolism of tanshinone IIA was studied in rats after a single-dose intravenous administration. In the present study, 12 metabolites of tanshinone IIA were identified in rat bile, urine and feces with two LC gradients using LC-MS/MS. Seven phase I metabolites and five phase II metabolites of tanshinone IIA were characterized and their molecular structures proposed on the basis of the characteristics of their precursor ions, product ions and chromatographic retention time. The seven phase I metabolites were formed, through two main metabolic routes, which were hydroxylation and dehydrogenation metabolism. M1, M4, M5 and M6 were supposedly tanshinone IIB, hydroxytanshinone IIA, przewaquinone A and dehydrotanshinone IIA, respectively, by comparing their HPLC retention times and mass spectral patterns with those of the standard compounds. The five phase II metabolites identified in this research were all glucuronide conjugates, all of which showed a neutral loss of 176 Da. M9 and M12 were more abundant than other identified metabolites in the bile, which was the main excretion path of tanshinone IIA and the metabolites. M12 was the main metabolite of tanshinone IIA. M9 and M12 were proposed to be the glucuronide conjugates of two different semiquinones and these semiquinones were the hydrogenation products of dehydrotanshinone IIA and tanshinone IIA, respectively. This hydrogenized reaction may be catalyzed by the NAD(P)H: quinone acceptor oxidoreductase (NQO). The biotransformation pathways of tanshinone IIA were proposed on the basis of this research.

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PubMed2006

Pharmacokinetics, absorption and tissue distribution of tanshinone IIA solid dispersion.

This study was designed to elucidate the pharmacokinetics, absorption, tissue distribution and plasma protein binding properties of tanshinone IIA, a highly lipophilic compound isolated from Salvia miltiorrhiza. Tanshinone IIA was isolated using a previously well developed LC-MS/MS method. Its pharmacokinetic characteristics, absolute bioavailability, tissue distribution and plasma protein binding properties were determined. The membrane permeability was evaluated using Caco-2 cells in monolayer. The pharmacokinetic plasma profile of tanshinone IIA after a single intravenous dosing exhibited a triexponential pattern consisting of rapid distribution (t1/2 alpha, 0.024 h), slow redistribution (t1/2 beta, 0.34 h) and terminal elimination phase (t1/2 gamma, 7.5 h). Tanshinone IIA preferentially distributed into the reticuloendothelial system, especially into liver and lung, after either intravenous or oral doses. Tanshinone IIA (99.2 %) bound highly to plasma proteins, among which lipoprotein played an important role (77.5 %). Tanshinone IIA absorption was extremely poor with an absolute bioavailability below 3.5 %. Absorptive saturation was deduced from the fact that the AUC and Cmax increased less proportionally to dose and Tmax was significantly prolonged. The poor absorption of tanshinone IIA may be caused by its low aqueous solubility and limited membrane permeability. There were no significant differences of the apparent permeability coefficient for all tested concentrations and for the apical to basolateral and reverse direction transport, suggesting a passive transport mode and no involvement of an efflux protein. In conclusion, tanshinone IIA has a suitable pharmacokinetic behavior except for its poor absorption. A pharmaceutical strategy for promoting its absorption should be designed to develop tanshinone IIA as a new drug candidate.

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PubMed2004

Induction of CYP1A by a diterpene quinone tanshinone IIA isolated from a medicinal herb Salvia miltiorrhiza in C57BL/6J but not in DBA/2J mice.

Effects of tanshinone IIA, an active diterpene quinone of the herbal medicine Salvia miltiorrhiza (Danshen), on cytochrome P450 (CYP), UDP-glucuronosyl transferase (UGT), and glutathione S-transferase (GST) were studied in the arylhydrocarbon (Ah)-responsive C57BL/6J (B6) and nonresponsive DBA/2J (D2) mice. Oral treatment of tanshinone IIA caused a dose-dependent increase of liver microsomal 7-methoxyresorufin O-demethylation (MROD) activity in B6 but not in D2 mice. In B6 mice, tanshinone IIA increased hepatic benzo(a)pyrene hydroxylation (AHH), 7-ethoxyresorufin O-deethylation, MROD, and 7-ethoxycoumarin O-deethylation activities. The levels of Cyp1A2 protein and mRNA were elevated. On the contrary, in D2 mice, tanshinone IIA decreased hepatic AHH and nifedipine oxidation activities and the CYP3A protein level without affecting other activities determined. Cyp1A2 protein and mRNA levels were not affected by tanshinone IIA in D2 mice. Tanshinone IIA had no effects on UGT and GST activities in both B6 and D2 mice. These results demonstrated that induction of CYP1A2 by tanshinone IIA depended on the Ah-responsiveness and occurred at pre-translational level.

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PubMed2006

Identification of tanshinone IIA metabolites in rat liver microsomes by liquid chromatography-tandem mass spectrometry.

Tanshinone IIA, the major component extracted from Radix salvia miltiorrhiza, has been observed to possess various kinds of pharmacological activities including antioxidant, prevention of angina pectoris and myocardial infarction and anticancer. Tanshinone IIA was incubated with rat liver microsomes and the resulting metabolites were identified by liquid chromatography/tandem mass spectrometry. The results showed the formation of three main hydroxyl metabolites. The three hydroxyl metabolites of tanshinone IIA were proved to be tanshinone IIB, hydroxytanshinone IIA and przewaquinone A by comparing the tandem mass spectra and the chromatographic retention time with that of the respective authentic compounds. Tanshinone IIB, hydroxytanshinone IIA and przewaquinone A are all the chemical components of total tanshinones. It was reasonable to presume that the three hydroxy metabolites of tanshinone IIA were pharmacologically active the same as tanshinone IIA and the total tanshinones.

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PubMed1999

Protective effects of sodium tanshinone IIA sulphonate against adriamycin-induced lipid peroxidation in mice hearts in vivo and in vitro.

Protective effects of sodium tanshinone IIA sulphonate against adriamycin-induced lipid peroxidation were investigated. Data showed that treatment with sodium tanshinone IIA sulphonate could prevent mice from decrease in body weight caused by adriamycin. It was found that myocardial lipid peroxidation in sodium tanshinone IIA sulphonate-treated mice was lower compared with that in adriamycin-treated ones. The activities of some endogenous antioxidant enzymes, such as superoxide dismutase, glutathione peroxidase and catalase, were higher in the sodium tanshinone IIA sulphonate group than that in the adriamycin group. In vitro experiments showed that sodium tanshinone IIA sulphonate could inhibit adriamycin-induced mitochondrial lipid peroxidation and swelling. Sodium tanshinone IIA sulphonate could scavenge adriamycin semiquinone free radical in heart homogenate dose-dependently. Thus, protective effects of sodium tanshinone IIA sulphonate may not only be related to its antioxidant activity but also to its regulation of antioxidant enzyme activities in the heart.

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PubMed2005

Tanshinone IIA isolated from Salvia miltiorrhiza elicits the cell death of human endothelial cells.

Tanshinone IIA, a major component extracted from the traditional herbal medicine, Salvia miltiorrhiza Bunge, is known to exhibit potent cytotoxicity against various human carcinoma cells in vitro. However, the mechanism by which tanshinone IIA produces this anti-tumor effect remains unknown. Since anti-neovascularization has generally been regarded as an effective strategy for anti-cancer therapy, we decided to investigate the mechanism underlying tanshinone IIA-mediated death of human endothelial cells. In this study, we demonstrate that tanshinone IIA elicits human endothelial cell death independent of oxidative stress. These events are partially calcium-dependent and actually dependent upon NAD(P)H: quinone oxidoreductase (NQO1) activity. Tanshinone IIA induces an increase in intracellular calcium, which triggers the release of cytochrome c, thus causing loss of the mitochondrial membrane potential (MMP), resulting in the subsequent activation of caspases. Blocking the induction of Ca2+ perturbation with BAPTA-AM partially rescued cells from tanshinone IIA-induced cytotoxicity. Additionally, blocking NQO1 activity with dicoumoral or inhibiting caspase activities with the general caspase inhibitor, z-VAD-fmk, prevented cell death induced by tanshinone IIA. Therefore, our results imply that tanshinone IIA-mediated cytotoxicity against human endothelial cells may occur through activation of NQO1, which induces a calcium imbalance and mitochondrial dysfunction, thus stimulating caspase activity.

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PubMed2006

Addition of tanshinone IIA to UW solution decreases skeletal muscle ischemia-reperfusion injury.

AIM: To investigate whether tanshinone IIA could improve the effect of UW solution for skeletal muscle preservation and to determine the dose range of tanshinone IIA providing optimal protection during ischemia and reperfusion. METHODS: Ischemic rat limbs were perfused with UW solution or UW plus tanshinone IIA (UW+T, 0.05, 0.1, or 0.2 mg/mL) for 0.5 h before reperfusion; controls (I/R) received no perfusion. Serum creatine phosphokinase (CPK), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) were measured pre-ischemia and after reperfusion (2-h, 4-h, and 6-h). Muscle water content, superoxide dismutase (SOD), malondialdehyde (MDA), adenosine triphosphatase (ATPase) were assessed pre-reperfusion and after 6-h reperfusion. Intercellular adhesion molecule-1 (ICAM-1) and apoptosis were detected after 6-h reperfusion. Reperfusion blood flow was monitored during reperfusion period. RESULTS: UW and UW+T prevented luxury perfusion during reperfusion and inhibited ICAM-1 expression and apoptosis after 6-h reperfusion. Serum CPK, AST, and LDH levels in UW rats were significantly less than those in controls after 2-h reperfusion (no difference, 4-h or 6-h reperfusion). After 4-h ischemia, there were significant differences in water content, MDA, SOD, and ATPase between UW and controls, but no difference after 6-h reperfusion. All tests with UW+T rats were significantly different from control results at corresponding durations. Higher tanshinone doses improved results. CONCLUSION: UW plus tanshinone IIA increased protection against I/R injury, suggesting that tanshinone IIA has clinical value.

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PubMed2006

Tanshinone IIA inhibits LPS-induced NF-kappaB activation in RAW 264.7 cells: possible involvement of the NIK-IKK, ERK1/2, p38 and JNK pathways.

Nuclear factor kappaB (NF-kappaB) activation by NF-kappaB-inducing kinase (NIK)-IkappaB alpha kinase (IKK) pathway and mitogen-activated protein kinases (MAPKs) pathway are important in inflammation. We recently found that the tanshinone IIA, a diterpene isolated from Salvia miltiorrhiza (S. miltiorrhiza), reduced the production of pro-inflammatory mediators in RAW 264.7 cells stimulated with lipopolysaccharide (LPS). However, little is known about the inhibitory mechanisms of tanshinone IIA on the production of pro-inflammatory mediators. To investigate the inhibitory mechanism, we determined the inhibitory effects of tanshinone IIA on the activation of NF-kappaB and IkappaB alpha phosphorylation, and also examined phosphorylation of NIK and IKK as well as the activation of MAPKs such as p38 MAPK (p38), extracellular signal-regulated kinases 1/2 (ERK1/2), and c-Jun N-terminal kinase (JNK) in RAW 264.7 cells stimulated with LPS. Tanshinone IIA inhibited NF-kappaB-DNA complex, NF-kappaB binding activity, and the phosphorylation of IkappaB alpha in a dose dependent manner. Tanshinone IIA also inhibited the translocation of NF-kappaB from cytosol to nucleus. Moreover, the phosphorylation of NIK and IKK as well as the phosphorylation of p38, ERK1/2, and JNK in the LPS-stimulated RAW 264.7 cells were suppressed by the tanshinone IIA in a dose dependent manner. These results suggest that tanshinone IIA may inhibit LPS-induced IkappaB alpha degradation and NF-kappaB activation via suppression of the NIK-IKK pathway as well as the MAPKs (p38, ERK1/2, and JNK) pathway in RAW 264.7 cells and these properties may provide a potential mechanism that explains the anti-inflammatory activity of tanshinone IIA.

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PubMed2002

[Effect of tanshinone IIA on CCl4-induced liver fibrosis in rats].

OBJECTIVE: To study the effect of tanshinone IIA on liver fibrosis in rats induced by CCl4. METHODS: Model of liver fibrosis in rats were induced by subcutaneous injection of CCl4 and malotilate was as positive control. The histological changes were observed with light microscope. The levels of ALT, AST, NO, HA, LN in serum and Hyp, MDA in liver tissue were determined to reveal the event liver damage. RESULT: Tanshinone IIA could significantly reduce the elevate levels of ALT, AST, NO, HA, LN in serum and Hyp, MDA in liver tissue. Pathological examination suggested tanshinone IIA has therapecuical effect on experimental liver fibrosis. CONCLUSION: Tanshinone IIA may have therapeutical effect on CCL4-induced liver fibrosis in rats.

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PubMed2003

[Protective effects of tanshinone IIA on injured primary cultured rat hepatocytes induced by CCl4].

OBJECTIVE: To investigate the effect of tanshinone IIA on carbon tetrachloridlde (CCl4) intoxicated primary cultured rat hepatocytes. METHODS: The rat hepatocytes were separated by perfusion with collagenase solution. Tanshinone IIA was added to the cultured medium after incubating the rat hepatocytes for 36 hours. At the same time, CCl4 was added to induce hepatocytes injury for 1 h. The levels of ALT, LDH, NO, SOD, MDA and cell viability after cultivation for 3 h were determined respectively. RESULT: Tanshinone IIA significantly improved cell viability, inhibited the decrease of SOD activity and the increase of ALT, LDH, MDA, NO levels CONCLUSION: Tanshinone IIA protected effectively the primary cultured rat hepatocytes against CCl4-induced injury.

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PubMed2004

Inhibition of osteoclast differentiation and bone resorption by tanshinone IIA isolated from Salvia miltiorrhiza Bunge.

Osteoclasts, multinuclear cells specialized for bone resorption, differentiate from the monocyte/macrophage lineage of hematopoietic cells. Intervention in osteoclast differentiation is considered an effective therapeutic approach to the treatment of bone diseases involving osteoclasts. In this study, we found that tanshinone IIA, originating from Salvia miltiorrhiza Bunge, inhibited the differentiation of osteoclasts. Addition of tanshinone IIA to the osteoclast precursor culture caused a significant decrease in the level of calcitonin receptor, c-Src, and integrin beta3 mRNA, which are normally upregulated during the osteoclast differentiation dependent on RANKL (receptor activator of nuclear factor kappa B ligand). RANKL activated the ERK, Akt, and NF-kappaB signal transduction pathways in osteoclast precursor cells, and tanshinone IIA suppressed this activation. Tanshinone IIA also inhibited the bone resorptive activity of differentiated osteoclasts, which was accompanied with the disruption of the actin ring. Thus, tanshinone IIA has the potential to ameliorate bone-resorption diseases in vivo by reducing both the number and activity of osteoclasts.

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