Effects of tanshinone II A on the myocardial hypertrophy signal transduction system protein kinase B in rats.

OBJECTIVE: To study the effect of tanshinone II A on the cell signal transduction system protein kinase B (Akt) in rats with hypertrophy of the myocardium induced by partial constriction of the thoracic aorta. METHODS: Rat models of myocardial hypertrophy were established by the thoracic aorta partial constriction method. Forty-eight rats were randomly divided into the sham-operative group, the model group, the valsartan treatment group, and the low-, medium-, and high-dose tanshinone treatment groups. The heart mass index (HMI), left ventricular mass index (LVMI), ejection fraction (EF), left ventricular posterior wall (LVPW), and interventricular septal thickness (IVS) were detected by high-frequency ultrasonography. The myocardial fiber diameter (MFD) was detected by HE staining, and the contents of p-Akt and p-Gsk3beta in the myocardium were detected by Western blot. RESULTS: Compared with the sham-operative group, the levels of HMI, LVMI, LVPW, IVS, and MFD were increased respectively in the other groups (P<0.05); the contents of p-Akt and p-Gsk3beta were also increased in the other groups. Compared with the model group, the levels of HMI, LVMI, LVPW, IVS, and MFD were decreased respectively in all treatment groups (P<0.05); the contents of p-Akt and p-Gsk3beta were decreased in all treatment groups as well. There was no significant difference, however, among the low-, medium-, and high-dose tanshinone treatment groups and the valsartan treatment group (P>0.05). CONCLUSION: Tanshinone II A can prevent myocardial hypertrophy by its action on the protein kinase B (Akt) signaling pathway.

[Effect of tanshinone II A on the calcineurin activity in proliferating vascular smooth muscle cells of rats].

OBJECTIVE: To study the effect of tanshinone II A (TSN) on angiotensin II (Ang II) induced proliferation of vascular smooth muscle cells (VSMCs). METHODS: VSMCs were cultured by explant attached method, and induced to proliferative cell model with Ang II. The effect of TSN in different concentrations on calcineurin (CaN) activity was detected by enzyme reaction phosphorus measurement; the CaN mRNA expression was detected by RT-PCR; and the expression of proliferating cell nuclear antigen (PCNA) were observed by immunocytochemical method. RESULTS: Compared with the normal control group, Ang II could significantly stimulate the proliferation of VSMCs, showing obviously elevated degree of proliferation activity (P <0. 01). After being treated with TSN, all the indexes, including CaN activity, CaN mRNA expression and PCNA expression, were obviously reduced in a dose-dependent manner (P<0.05, P<0.01). CONCLUSION: VSMCs proliferation can be inhibited by TSN in a dose-dependent manner and the inhibiting mechanism may be related to the down-regulation of CaN activities and the inhibition on CaN mRNA and PCNA expressions.

Postconditioning in cardiopulmonary resuscitation: a better protocol for cardiopulmonary resuscitation.

Although current cardiopulmonary resuscitation (CPR) performance can increase the rates of restoration of spontaneous circulation (ROSC) and survival to hospital admission, the discharge rates of patients remain disappointing. The high mortality rate is attributed to post-cardiac arrest brain injury. The discovery of the postconditioning phenomenon opens a door to endogenous neuroprotection. The protection mechanisms of postconditioning include attenuating mitochondrial calcium overload and reducing oxidative stress, recruiting the reperfusion injury salvage kinase (RISK) pathway, and preventing from the mitochondrial permeability transition pore (mPTP) opening at the time of reperfusion. An advantage of postconditioning lies in the potentially clinical application in the unexpected ischemic situation. Prior laboratory researches indicate that postconditioning may lessen the reperfusion/ischemia-induced injury in unexpected coronary occlusion, acute myocardial infarction and stroke. Because cardiac arrest, stroke and acute myocardial infarction have a similar pathophysiological process, we hypothesize that postconditioning could be used in the clinical practice of CPR to treat patients with post-cardiac arrest brain injury. We propose a novel protocol of "Postconditioning cardiocerebral resuscitation (Post-CCR)". The Post-CCR includes applying three cycles of 18s chest compression and 10s interruption for ventilation first, and then executing chest compression only CPR until the patients return spontaneous circulation. Post-CCR can not only provide vital blood flow to the heart and brain but also activate endogenous protective mechanism to lessen post-cardiac arrest brain injury. We consider that it would become a feasible, safe and efficient cerebralprotective intervention in the prevention and alleviation of post-cardiac arrest brain injury, which would also improve the outcome after cardiac arrest.

Sodium tanshinone IIA sulfonate attenuates angiotensin II-induced collagen type I expression in cardiac fibroblasts in vitro.

Cardiac fibrosis occurs after pathological stimuli to the cardiovascular system. One of the most important factors that contribute to cardiac fibrosis is angiotensin II (AngII). Accumulating studies have suggested that reactive oxygen species (ROS) plays an important role in cardiac fibrosis and sodium tanshinone IIA sulfonate (STS) possesses antioxidant action. We therefore examined whether STS depresses Ang II-induced collagen type I expression in cardiac fibroblasts. In this study, Ang II significantly enhanced collagen type I expression and collagen synthesis. Meanwhile, Ang II depressed matrix metalloproteinase-1 (MMP-1) expression and activity. These responses were attenuated by STS. Furthermore, STS depressed the intracellular generation of ROS, NADPH oxidase activity and subunit p47(phox) expression. In addition, N-acetylcysteine the ROS scavenger, depressed effects of Ang II in a manner similar to STS. In conclusion, the current studies demonstrate that anti-fibrotic effects of STS are mediated by interfering with the modulation of ROS.

[Effect of tashinone on nitric oxide synthase in hypertrophic cardiomyocyte of rats suffered abdominal aorta constriction].

OBJECTIVE: To explore the molecular biological mechanism for tanshinone II A reversing left ventricular hypertrophy, it would be studying the effect of tashinone on the endothelial nitric oxide synthase (eNOS) and protein kinase C (PKC) in the hypertrophic cadiocyte of rats suffered abdominal aorta constriction. METHOD: SD rats were operated with abdominal aorta constriction and 8 rats were done with sham surgery. After 4 weeks, all rats were divided into 4 groups: myocardial hypertrophy group, low dose tanshinone II A group (10 mg x kg(-1) x d(-1)), high dose tanshinone II A group (20 mg x kg(-1) x d(-1)) and valsartan group (10 mg x kg(-1) d(-1) intragastric administration). 8 weeks later, the rats were used to measure the left ventricular mass index (LVMI) with the tissue of left ventricle and myocardial fiber dimension (MFD) by pathological section and HE stain, to detect the nitric oxide content by nitrate reductase, to detect the genic expression of eNOS by RT-PCR and to detect the activity of protein kinase C (PKC) by Western blotting. RESULT: 1) The blood pressure in group myocardial hypertrophy [(186 +/- 13) mmHg] and tansginone II A [low and high dose (188 +/- 11,187 +/- 14) mmHg] was obviously higher than that in group sham surgery and valsartan group [vs (117 +/- 8, 136 +/- 15) mmHg, P < 0.01]. But there was no difference between group myocardial hypertrophy and group tanshinone II A (low and high dose). 2) The LVMI and MFD were obviously higher in group tanshinone II A low and high dose) and group valsartan than those in group sham surgery (P < 0.05), and lower than those in group myocardial hypertrophy (P < 0.01). 3) The NO level was obviously higher in group tanshinone II A (low and high dose) and group valsartan than that in group myocardial hypertrophy (12.78 +/- 1.66, 11.95 +/- 1.39, 12.26 +/- 2.08 vs 5.83 +/- 1.06) micromol x L(-1), (P < 0.01 ), and lower than that in group sham surgery (vs 19.35 +/- 1.47) micromol x L(-1), (P < 0.05). 4) The expressive level of eNOS mRNA and protein in myocardial hypertrophy group was less than that in other groups (P < 0.01). And valsartan group was less than tanshinone II A groups and sham surgery group (P < 0.05), but there were no difference among the two tanshinone II A groups and sham surgery group. 5) The level of PKC protein in group myocardial hypertrophy was obviously higher than that in all the other groups (1.291 +/- 0.117 vs 0.563 +/- 0.094, 0.605 +/- 0.051, 0.519 +/- 0.062, 0.827 +/- 0.086, P < 0.01), and the level in group valsartan was higher than that in group sham operation and group tanshinone II A (low and high dose). CONCLUSION: NO/NOS system in local myocardium has close relationship with the pathological process for myocardial hypertrophy. Tanshinone II A can produce the pharmacological action to reverse myocardial hypertrophy by inhibiting the activity of PKC and promoting the genic expression of eNOS in local myocardium and the production of endogenous NO.

Role of Shenfu Injection in rats with systemic inflammatory response syndrome.

OBJECTIVE: To investigate the role of Shenfu Injection (SFI) in rats with systemic inflammatory response syndrome (SIRS). METHODS: The SIRS rat model was induced by the intravenous injection of lipopolysaccharide (LPS). Forty-five male Wistar rats were randomly divided into 3 groups, the sham operative control group (control group, n=5), the SIRS model group (model group, n=20) and the SFI treatment group (SFI group, n=20). LPS was injected through the external jugular vein (12 mg/kg, 6 mg/mL) to all rats except for those in the control group, and SFI (10 mL/kg) was given to those in the SF group only once through intraperitoneal injection, while the normal saline (10 mL/kg) was given to those in the model group. For those in the control group, normal saline was given through the external jugular vein (2 mL/kg) and intraperitoneal injection (10 mL/kg). Then, rats in the model group and SFI group were divided into 4 subgroups according to the time points, i.e., 1 h, 2 h, 4 h and 6 h subgroups, 5 rats in each group. The activity of nuclear factor of kappa B (NF-kappa B) of in blood mononuclear cells and the plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin 6-(IL-6) were determined using enzyme-linked immunoabsordent assay (ELISA) at 1 h, 2 h, 4 h and 6 h after modeling. Histopathologic changes of the lung and liver were observed under a light microscope. RESULTS: Compared with the control group, the activity of NF-kappa B in mononuclear cells and the plasma level of TNF-alpha were obviously increased at each time points (all P<0.01), reaching the peaks at 2 h after modeling. The plasma level of IL-6 increased gradually as time went by in the model group (P<0.01). Pathological examination showed pulmonary alveoli hemorrhage, edema and inflammatory cell infiltration in the lung tissue, and angiotelectasis, congestion, and local necrosis in the liver tissue in the model group. Compared with the model group, the activity of NF-kappa B and the levels of TNF-alpha and IL-6 in plasma decreased significantly in the SFI group (P<0.01), and the pathological injury in the lungs and liver was significantly alleviated. CONCLUSION: SFI plays a protective role by inhibiting the activity of NF-kappaB, and reducing the expressions of TNF-alpha and IL-6 in SIRS rats.

[Effects of tetrandrine on Ang II-induced cardiomyocyte hypertrophy and p-ERK1/2 expression].

OBJECTIVE: To observe effects of tetrandrine (Tet) on angiotensin II (Ang II)-induced cardiomyocyte hypertrophy and the activity and expression of phosphorylated ERK1/2 (p-ERK1/2). METHOD: In the primary culture of neonatal rat cardiomyocytes, as indexes of cardiomyocyte hypertrophy, pulsation rate was measured under phase contrast microscope. Cell size was determined by cell morphology analytical system. The total protein was determined by coomassie brilliant blue and protein synthesis rate was measured by [3H]-Leucine incorporation. ERK activity was measured by immuno-precipitation. The expression of p-ERK1/2 was assessed using Western blot. RESULT: Tet can decrease Ang II-induced elevations of the pulsation rate, cell size, total protein and protein synthesis rate; inhibit the activity and expression of p-ERK1/2. CONCLUSION: The anti-hypertrophic effect of Tet on Ang II-induced cardiomyocyte hypertrophy was associated with inhibition of ERK1/2 signaling pathway.

[Effects of rotundine injection on nitric oxide synthase in tissues of different organs after ischemia/reperfusion of brain in rats].

OBJECTIVE: To explore the protective effect of rotundine injection on lung, liver and kidney damages after cerebral ischemia/reperfusion (I/R) injury in rats based on the activity changes of nitric oxide synthase (NOS). METHODS: Seventy-six rats were randomly divided into three groups: sham operation group, I/R injury group and treatment group, and determinations were done at five different time points. The cerebral I/R models were reproduced by improved 4 vessels occlusion method. The activities of NOS in the lung, liver and kidney were measured in all the rats at 2, 6, 12, 24 and 48 hours after reperfusion. RESULTS: Compared with sham operation group, the activities of total NOS (tNOS) were significantly increased at 2, 12 and 24 hours in I/R injury group (P<0.05 or P<0.01), with the peak value at 12 hours (all P<0.01). The activities of constitutive NOS (cNOS) were increased significantly at 2 hours (all P<0.05), and those of induced NOS (iNOS) were increased at 12 hours (all P<0.01). The activities of iNOS were still high at 24 hours (all P<0.05), and approached the levels of sham operation group at 48 hours. Compared with I/R injury group, the activities of cNOS in various organs increased much higher at 2 hours in treatment group (all P<0.05). But those of iNOS were significantly decreased after 12 hours (P<0.05 or P<0.01). CONCLUSION: The various types of NOS play different roles in the lung damages after brain I/R injury at different stages in rats. Rotundine injection can ameliorate the damages by modulating the activities of different types of NOS.

[Construction and identification of plasmid vector encoding two survivin shRNA].

OBJECTIVE: To construct and identify the eukaryotic expression plasmids encoding two short hairpin RNA (shRNA) of survivin for the purpose of paving the way for the studies of targeted gene therapy for prostatic carcinoma (PCa). METHODS: Two shRNA of survivin were designed and synthesized respectively, and then both were cloned into plasmids. Finally, the recombinant plasmids were confirmed by sequencing and agarose gel electrophoresis after restriction digestion. RESULTS: The recombinant plasmids encoding two survivin shRNA were constructed and the aim sequence obtained. CONCLUSION: Successful construction of the recombinant provides a sound basis for the research of targeted gene therapy for PCa.

[Influence of hypoxia-reoxygenation on nitric oxide synthesis III gene expression in cultured cerebral arterial endothelial cell].

OBJECTIVE: To investigate the change of nitric oxide synthase (NOS) III gene expression in cultured cerebral arterial endothelial cells during hypoxia and reoxygenation. METHODS: (1) The cells were divided into six groups: control, hypoxia for 1 hour, reoxygenation for 2, 6, 12, 24 hours after hypoxia for 1 hour. (2) The expression of NOSIII mRNA was detected semiquantitatively by reverse transcription-polymerase chain reaction (RT-PCR). (3) Immunocytochemistry was used to detect the expression of NOSIII protein. RESULTS: (1) The gene and protein expression of NOSIII was increased during hypoxia for 1 hour. (2) The gene and protein expression of NOSIII was decreased during reoxygenation for 2, 6, 12 hours after hypoxia for 1 hour, especially at 6 hours after reoxygenation. After cells were reoxygenation for 24 hours, the expression was restored to the normal level. CONCLUSION: The experiment showed that hypoxia could increase the levels of NOSIII gene and protein expression and reoxygenation inhibited the increment of this gene expression.