Effect of Puerarin Combined with Tanshinone ⅡA on t-PA, PAI-1 and Oxidative Stress in DM Rats with Vascular Lesions / 中国实验方剂学杂志

Objective:To observe the protective effect and mechanism of combination of puerarin combined with tanshinone ⅡA on diabetes mellitus (DM) rats with vascular lesions. Method:The SD rats (fed with high-fat diet) were administrated with streptozotocin(STZ) through intravenous injection to make the model of diabetic vascular lesions. The successfully modeled rats were randomly divided into the model control group, the high-dose group (0.5 g·kg-1+1.0 g·kg-1), the middle-dose group (0.25 g·kg-1+0.5 g·kg-1), the low-dose group (0.05 g·kg-1+0.1 g·kg-1), the puerarin group (0.25 g·kg-1), the tanshinone ⅡA group (0.5 g·kg-1) and the positive control group (Metformin, 0.09 g·kg-1). Each group was administrated with drugs respectively by gavage for 70 days. After intervention in each group, the general conditions and body weight of the rats were observed. The contents of blood grucose and blood lipids were determined by automatic biochemical analyzer. The contents of insulin, advanced glycation end products (AGEs), superoxide dismutase(SOD), glutathione peroxidase (GSH-Px) in serum, the contents of tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1) and thromboxane B2 (TXB2) in plasma, as well as the contents of AGEs and oxidized low-density lipoprotein(ox-LDL) in aorta homogenate were detected by enzyme-linked immunosorbent assay(ELISA). The content of malondialdehyde(MDA) in serum was determined by chemical colorimetry. Pathological changes of coronary tissue were observed by htoxylin eosin(HE) staining. The expression of PAI-1 protein of aorta was observed by immunohistochemistry. Result:Compared with the normal control group, in the model group, the levels of blood grucose and blood lipids (PPPP2 in plasma (PPPPPPPPP2 in plasma (PPPPPPPConclusion:Puerarin combined with Tanshinone ⅡA could relieve vascular lesions of DM rats. The mechanisms may be related to the reduction of oxidative stress and the regulation of coagulation-fibrinolysis system.

Zinc-Triggered Induction of Tissue Plasminogen Activator and Plasminogen in Endothelial Cells and Pericytes

Cerebral amyloid angiopathy (CAA) is common in patients with Alzheimer's disease (AD) and may contribute to cerebral hemorrhage. We previously demonstrated that tissue plasminogen activator (tPA) and plasminogen (PLG) accumulated at the periphery of compact amyloid-cored plaques and in the walls of CAA-containing blood vessels in the brains of Tg2576 mice, a widely used AD mouse model. We had also observed that zinc-triggered tPA and PLG induction were observed in mouse cortical cultures. Because zinc also accumulates in amyloid plaques and blood vessel walls in AD brains, we examined whether zinc increases mRNA and protein levels of tPA and PLG in brain endothelial cells and pericytes. Four hours after the exposure of brain endothelial cells (bEnd.3) to 40 microM zinc, the mRNA and protein expressions of tPA and its substrate PLG were significantly increased. In the case of brain pericyte cultures, increases in tPA and PLG expression were also detected 2 hr after treatment. However, amyloid-beta (Abeta)1-42 oligomers did not augment tPA and PLG expression in bEnd.3 cells and pericytes, suggesting that zinc but not Abeta induces tPA and PLG accumulation in CAA found in the AD brain.

The Effect of Tissue Plasminogen Activator on Intimal Hyperplasia after Balloon Injury to Rat Aorta

PURPOSE: Thrombus formation enhances both neointima formation and clinical restenosis after vascular injury or angioplasty. Thrombotic occlusions and intimal hyperplasia limit the success of vascular reconstructive procedures. Thrombolysis is expected to improve the outcome for both restenosis and acute arterial occlusion after injury. Tissue-type plasminogen activator (tPA) is commonly used clinically, and it is thought to play a critical role in vascular remodeling by mediating intravascular clot lysis and modulating cell migration within the vessel wall. However, there is controversy about the late effects of tPA on the vascular lumen either for preventing or enhancing intima hyperplasia in vivo. Thus, this study was done to evaluate the impact of a clinical infusion of tPA on the neointima formation after a balloon injury. METHOD: Forty male Sprague- Dawley rats weighting of 250~300 gm each were underwent aortic intimal denuation with a 2F balloon catheter. The rats were divided into two groups: the control group (n=20: normal saline infusion), and the*ean IMAR on the 21st day was 1.14+/-0.16 in the control group and 1.10+/-0.11 in the experiment group. The mean IMAR was lower in the experiment group, but the result was not statistically significant. In comparison to the gelatinolytic activity of MMP-9 and, activated MMP-2, there was no significant difference between the two groups. CONCLUSION: These results suggest that the effect of tPA on intimal hyperplasia after balloon injury to rat aorta showed minimal significance.

Retnal Toxicty of Intravitreal Tissue Plasminogen Activator with C3F8 Injection in Rabbit Eyes

PURPOSE: To determine the concentration at which a mixed injection of tissue plasminogen activator (tPA) and C3F8 gas is toxic, we studied the histopathological changes in the rabbit retina. METHODS: Only tPA was injected into the right vitreous cavities of 18 normal pigmented rabbits at doses of 25 micro gram/0.1mL, 50 micro gram/0.1mL, and 100 micro gram/0.1mL, 6 rabbits per dosage. In the same rabbits, tPA and C3F8 (0.2cc) were simultaneously injected into the left vitreous cavities at doses of 25 micro gram/0.1mL, 50 micro gram/0.1mL, and 100 micro gram/0.1mL. All of the eyes were examined by slit lamp biomicroscopy and indirect ophthalmoscopy at 5, 10, and 15 days after the injection, and then they were enucleated for histopathological evaluation. RESULTS: Retinal pigmentary alterations were centered around the injection site 3 days postoperatively in the eyes receiving doses of 50 micro gram/0.1mL or greater. On light microscopy(LM), the involved areas showed vacuolization in the photoreceptor elements and the inner nuclear layer(INL) at a dose of 25 micro gram/0.1mL at postoperative 5 days and the vacuolar changes disappeared at postoperative 15 days. But at doses of 50 micro gram/0.1mL or greater, loss, contracture, and vacuolization of the photoreceptor outer segment (POS) and vacuolization of INL were noted at postoperative 15 days. On LM, at a dose of 25 micro gram/0.1mL, the involved areas showed vacuolization in POS and mitochondrial swelling of the photoreceptor inner segment (PIS) at postoperative 5 days. The mitochondrial swelling of PIS disappeared at postoperative 15 days. However, at doses of 50 micro gram/0.1mL or greater, loss and contracture of POS and mitochondrial swelling of PIS were noted at postoperative 15 days. The retinal damage from simultaneous injection of tPA and C3F8 at doses of 25, and 50 micro gram/0.1mL was equal to or less than that of only tPA injection, whereas at a doses of 100 micro gram/0.1mL the damage was greater. CONCLUSIONS: At doses of 50 micro gram/0.1mL or greater, irreVersible retinal toxicity was noted histopathologically in rabbit eyes. At doses of 25, and 50 micro gram/0.1mL, the degree of retianl damage did not seem to be affected by whether C3F8 was injected concomitantly or not.

Effects of 38.DEG.C. Bathing for 30 min on Hemostatic Function and Autonomic Nervous Function in Patients with Cerebral Infarction / 日本温泉気候物理医学会雑誌

Effects of 38°C 30-minute bathing on hemostatic function and autonomic nervous function were studied in 15 48-to-72-year-old patients with cerebral infarction. Blood samples were collected three times: immediately before the bathing, at the end of 30 minutes of bathing, and 30 minutes after the bathing. Hematocrit values and fibrinogen concentrations decreased during bathing and returned to the pre-bathing levels 30 minutes after bathing. This indicates that bathing caused hemodilution due to the fluid shift. During bathing, noradrenaline decreased at a rate significantly higher than that of hemodilution while the sympathetic nervous function, which was evaluated by spectral analysis of sequential variation in arterial blood pressure, was not suppressed. The autonomic nervous system seemed to be inactive in these patients. Coagulation time (PT and APTT) and platelet factor (β-TG and PF4) showed few changes. In the fibrinolytic system, however, tissue plasminogen activator (t-PA) antigen levels increased and plasminogen activator inhibitor type-1 (PAI-1) levels decreased after 30 minutes of bathing. This suggests that fibrinolytic activity was enhanced by 38°C bathing for 30 minutes. Thus, subthermal bathing with comfort may be useful in preventing cerebral infarction.

Antithrombotic Effect on Hemostasis during Water Immersion at Indifferent Temperature / 日本温泉気候物理医学会雑誌

Studies on the effects of heating as well as the mineral components of hot spring water have been conducted to investigate the effects of balneotherapy. However, few studies have been conducted on the effects of hydrostatic pressure and buoyancy during water immersion. Therefore, we investigated the effect of water immersion up to the neck at thermoneutral temperature on hemostatic activity.<br>Nine healthy men aged 22 to 34 were immersed up to the neck in the standing position in thermoneutral water (34.0±0.5°C) for two hours. The heart rate decreased immediately after starting water immersion and remained low during the immersion. Hematocrit values (Ht) of the blood samples taken from the ante-cubital vein decreased by 3.4% in average. The decrease in Ht was more prominent in the blood samples taken from the earlobe (4.0%), suggesting that hemodilution due to fluid shift was stronger in the upper part of the body. The time until euglobulin clot lysis shortened immediately after starting the immersion. Although fibrinolytic activity was enhanced, the concentration of tissue plasminogen activator (t-PA) antigen in the blood decreased gradually during the immersion and tended to return to the original level 30 minutes after immersion. A larger decrease in the concentration of plasminogen activator inhibitor-1 (PAI-1) antigen in the blood was observed immediately after starting the immersion, and it remained low for 30 minutes after immersion. An increase in fibrinolytic activity due to the decrease in PAI-1, not in t-PA, was observed during water immersion at thermoneutral temperature and the activation of fibrinolytic system without activation of the coaguration system was also observed.

Effect of Buyang Huanwu Decoction and its active fraction on antithrombosis in cultured vascular endothelial cells and protein kinase C / 中草药

Objective To investigate the antithrombosis effects of Buyang Huanwu Decoction(BHD) and its active fractions on cultured vascular endothelial cells(VEC) following the stimulation of thrombin and their mechanism.Methods The human umbilicus vein endothelial cells(ECV 304) were cultured in media containing 10 U/mL thrombin and different dosese of drugs.The levels of tPA and PAI-1 were detected by ELISA,the expression of TF,TFPI,and TM mRNA was measured by RT-PCR,and the expression of PKC? was examined by immunohistochemical staining 24 h later.Results Compared to the control without any treatment,the release of tPA was increased evidently(P0.05).Compared to the data after the mere stimulus of thrombin,each dose of BHD increased the release of tPA(P0.05);And glycoside(1.25 mg/mL) increased the release of tPA(P