Platelet function tests and Chinese medicines with antiplatelet function:a review / 中国中药杂志

Platelet function tests have been increasingly used to assist in the diagnosis of platelet disorders and prethrombotic state, monitoring of the efficacy of antiplatelet therapies, and personalized treatment. On the basis of light transmission aggregometry, new methods for platelet function test have been developed successively. At present, the research and development of platelet function detector is in its infancy in China. The active constituents of antiplatelet Chinese medicines can be classified into terpenoids, flavonoids, saponins, organic acids, lignans, diketones, volatile oils, and stilbenes. The results of dose-antiplatelet effect relationship of Chinese medicines and the active constituents showed that the effective concentration of the extracts or monomers of Chinese medicines was at micromolar level(μmol·L~(-1)), among which salvianolic acid B and ginkgolide K, ginkgolide B, and ginkgolide A had the strongest antiplatelet effect. These results suggest that the antiplatelet effect of Chinese medicine may be weaker than that of chemical drugs and biological products. Therefore, it is necessary to explore the structure-activity relationship of the active constituents in existing Chinese medicines and further improve their efficacy through structure modification. The antiplatelet effect of Chinese medicines and the constituents involves multiple pathways and multiple targets. These research results provide a reference for clinical application of them. However, there is still a lack of large-scale multi-center clinical trials to confirm the efficacy and safety of them. The regularity of the relationship between the structures of various constituents and their corresponding functions is still unknown and the relevant signal transduction pathways and structure-activity relationship need to be further studied. This paper summarized and analyzed the determination methods of platelet functions and the research results of antiplatelet Chinese medicines, which is of reference value for the research of effective and safe antiplatelet Chinese medicines.

On shear-induced platelet aggregation and its therapy / 药学学报

It is now widely accepted that platelet aggregation plays an important role in physiological hemostasis and pathological thrombosis associated with cardiovascular and cerebrovascular diseases. Anti-platelet aggregation drug research is also a hot spot of current research. The biggest challenge of antiplatelet therapy has been the molecular overlap of the hemostasis and thrombosis, leading to a serious risk of bleeding. Recent studies have emphasized the importance of shear stress generated from blood flow, which will primarily drive platelet activation and aggregation in thrombosis. So if we can take advantage of the differences between the physiological and pathological vascular blood flow environment, the development of selective anti-platelet therapy may be a safer treatment for cardiovascular and cerebrovascular diseases. In this review, we discuss the underlying mechanisms of shear-induced platelet activation. Later, we summarize the effects and mechanisms of compounds and traditional Chinese medicine on shear-induced platelet activation. The aim is to provide a reference for the study of biological pharmacology of traditional Chinese medicine for promoting blood circulation and removing blood stasis.

Effects of Xueshuantong Injection on thrombosis formation and blood flow in rats / 中国中药杂志

The aim of this paper was to explore the effect of Xueshuantong Injection(freeze-dried powder,XST) on κ-carrageenan-induced thrombosis and blood flow from the aspects of interactions among blood flow,vascular endothelium and platelets. Fifty male Sprague-Dawley rats(190-200 g) were randomized into five groups: control group, model group, heparin sodium(1 000 U·kg~(-1)) group, low-dose and high-dose(50, 150 mg·kg~(-1)) XST groups. Rats were intraperitoneally injected with corresponding drugs and normal saline(normal control and model groups) for 10 days. One hour after drugs were administered intraperitoneally on the 7 th day, each rat was injected with κ-carrageenan(Type Ⅰ, 1 mg·kg~(-1)) which was dissolved in physiological saline by intravenous administration in the tail to establish tail thrombus model. The lengths of black tails of the rats were measured at 2, 6, 24 and 48 h after modeling. Vevo®2100 small animal ultrasound imaging system was used to detect the internal diameter of rat common carotid artery, blood flow velocity and heart rate, and then the blood flow and shear rate were calculated. Meanwhile, the microcirculatory blood flow perfusion in the thigh surface and tail of rats were detected by laser speckle blood flow imaging system. Platelet aggregometry was used to detect the max platelet aggregation rate in rats. Pathological changes in tail were observed through hematoxylin-eosin staining, and Western blot was used to detect the protein content of platelet piezo1. According to the results, XST could inhibit the rat tail arterial thrombosis and significantly reduce the length of black tail(P<0.05). The blood flow of common carotid artery in XST low dose group was significantly higher than that in the model group(P<0.05). XST high dose group could significantly increase the microcirculatory blood flow perfusion of the tail in rats as compared with the model group(P<0.05). XST high dose group could significantly inhibit platelet aggregation rate(P<0.05) and XST low dose group could significantly inhibit platelet piezo1 protein expression(P<0.01). In summary, XST could play an effect in fighting against thrombosis induced by κ-carrageenan in rats, which may be related to significantly inhibiting platelet aggregation, improving body's blood flow state, maintaining normal hemodynamic environment and affecting mechanical ion channel protein piezo1.

Development of bioassay method in quality control of traditional Chinese medicine / 中国中药杂志

On the basis of chemical content determination， the bioassay methods can be used to comprehensively evaluate and control the Chinese medicine compound. This paper analyzed the newly published literature on traditional Chinese medicine(TCM) bioassay. The selection of standard control substances and the establishment of experimental system are the main difficulties in bioassay. At present， the standard control substances mainly include： different sources of products with basically similar components， certified medicinal materials， genuine medicinal materials， commonly used chemical drugs or biological products with similar pharmacological functions， as well as Chinese medicine potency conversed by activity of biological products. In this paper， the common bioassays would be summarized from the clinical efficacy of activating blood circulation and removing stasis and clearing heat and detoxification. It is one of the important contents in the industrial production of traditional Chinese medicine to gradually establish the bioassay platform of Chinese medicine from the enterprise's internal control to the industry. recognition.

Anti-platelet adhesive effect and mechanisms of Xueshuantong capsules under flow conditions / 中国中药杂志

To investigate the anti-platelet adhesive effect and possible mechanisms of Xueshuantong capsule (XST) under flow conditions. Human umbilical vein endothelial cells (HUVECs) and human platelets were employed as experimental materials, and TNF-α (20 μg•L⁻¹) was used to establish vascular endothelial cell injury models. In vivo flow conditions were simulated under controlled shear stress of 0.1 Pa and 0.9 Pa by Bioflux1000 assays accordingly. Anti-platelet adhesive effects of XST at 0.3 g•L⁻¹ were dynamically monitored by microscopic time-lapse photography. Western blotting was employed to detect the VCAM-1 expression on endothelial cells, and the release of 6-keto-PGF1α and TXB2 was tested by radioimmunoassay. The results showed that XST could inhibit the platelets adhesion under both physiological and pathological flow conditions, and the inhibition rate was 15.0% and 34.1% respectively. Under pathological low shear stress or static conditions, XST could significantly inhibit endothelial cells VCAM-1 expression and TXB2 release (P<0.05). These results suggested that XST inhibited platelets adhering to injured endothelium via decreasing VCAM-1 expression and TXA2 secretion from endothelium. From the interactions among blood flow, vascular endothelium and platelets, the anti-thrombosis effects of XST were possibly related to endothelial cells protection and therefore inhibiting platelets adhesion. Under different flow conditions, the antiplatelet adhesion effect of XST was different, and the pathological low shear stress was more conducive to the efficacy of XST.

Anti-platelet aggregation bioassay based quality control for XST capsules / 中国中药杂志

A in vitro platelet aggregation bioassay was developed for the quality control of XST capsules. The in vitro anti-platelet aggregation effect in rats was observed to detect the bioactivity of XST capsules. Panax notoginseng saponins and Xuesaitong lyophilizedpowder for injection were taken as standard control substances to determine the potency. According to the results, XST capsules showeda significant inhibitory effect on thrombin-induced platelet aggregation in a dose-dependent manner. The in vitro anti-platelet activity oflyophilized powder for injection was stabler than that of Panax notoginseng saponins, and so suitable to serve as a standard control substance. The biological potency of XST capsules compared with standard control substance was detected by using parallel line assay. According to the results, the established bioassay method had a good repeatability (RSD 2.92%). The sample test results could pass thereliability test(linear deviation P > 0.05, parallel deviation P > 0.05). This bioassay method could be used as one of the complementary quality control methods for XST capsules.

Influence of fluid shear stress on anti-platelet aggregation of salvianolic acid B / 医用生物力学

Objective To study effects of flow shear stress combined with salvianolic acid B (Sla B) on anti-platelet aggregation and its possible mechanism under the theoretical framework of biomechanopharmacology. Methods 2×4 factor experimental design was employed. By using Bioflux 1000 microfluidic system, shear stresses of 0.02 Pa and 1.5 Pa were applied together with four levels of Sla B concentration treatment on human vascular endothelial cells (HUVECs) for 20 hours. Then the cell supernatant was collected to detect concentration of 6-keto-PGF1α and vWF by ELISA and their effects on ADP-induced platelet aggregation were tested. Immunofluorescence method was used to detect vWF in endothelial cell cytoplasm. Results Physical shear stress of 1.5 Pa combined with Sla B of 100 μg/mL could significantly promote the endothelial secretion of 6-keto-PGF1α as compared to low shear stress condition (P<0.05). The endothelial cell supernatant under shear stress of 1.5 Pa showed an obvious anti-platelet aggregation effect. As the single factor, shear stresses significantly influenced vWF secretion (P<0.01), but Sla B had no obvious effects on vWF secretion. Conclusions Sla B inhibited ADP-induced platelet aggregation by increasing endothelial secretion of PGI2 under physical shear stresses. From the view of biomechaopharmacology (interaction between blood flow, blood vessel and blood), the physical flow shear stress is beneficial for the anti-thrombosis effect of Sla B.

Biomechancial issues in traditional Chinese medcine research / 医用生物力学

Traditional Chinese medicine (TCM) has been formed and developed in medical practices over thousands of years, while biomechanics as a new research direction in TCM has been developing rapidly in recent years. Biomechanics in TCM encompasses abundant contents, such as hemodynamics in meridians, substance transport of Yin-Yang and the Five Elements, hemodynamics of pulse manifestation, heat conduction in tongue diagnosis, biomechanics of orthopaedics and traumatology, mechanics of acupuncture, massage and manipulation, TCM medical device, biomechnopharmacology and etc. Journal of Medical Biomechanics has published some papers about TCM biomechanics in the past years, and in this issue, a special column of TCM biomechanics in three research directions is organized, including massage and manipulation, fracture fixator by TCM treatment, and Tai Chi Quan, so as to arouse readers’ interest in TCM biomechanics.

Recent pharmacological study on sanshengwan decoction / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the pharmacological function of Sanshengwan decoction with modern medical and rheological techniques, and also to discuss the differences between injury blood stasis syndrome and yang deficiency blood stasis syndrome.</p><p><b>METHOD</b>Animal model for injury blood stasis syndrome was found by bruise; Animal model for yang deficiency blood stasis syndrome was done by exhausting the animals in a - 15 degrees C freezer for 4 hours.</p><p><b>RESULT</b>Blood fibrinogen content, platelet aggregation and blood coagulation time were significantly increased, plasma viscosity and blood coagulation slope was significantly decreased in injury blood stasis syndrome group. Blood fibrinogen content, platelet aggregation and blood coagulation time were dropped markedly. Blood coagulation slope was raised noticeably in yang deficiency blood stasis syndrome group. Sanshengwan decoction behaved very good effects on removing blood stasis on both of the two kinds of animal models.</p><p><b>CONCLUSION</b>Though hemorheological index and experimental data in the two kinds of animal models were behaved statistically significance, but the experimental representative indexes were obviously difference. Sanshengwan the tipical herbal medicine for eliminating blood stasis syndrome showed significantly effects on both of the two kinds of animal models, but the effects on injury blood stasis syndrome group was better than the other animal model's.</p>

Specific inhibiting effects of Ilexonin A on von Willebrand factor-dependent platelet aggregation under high shear rate / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Ilexonin A (IA), purified from the Chinese herbal medicine Maodongqing (Ilex pubescens Hook, et Arn) has been commonly used in south China to treat thrombotic disorders. In this study, we aimed to study the inhibiting effects and mechanism of IA on von Willebrand factor (vWF)-dependent high shear-induced platelet aggregation.</p><p><b>METHODS</b>vWF-dependent high shear (10,800 s(-1)) induced aggregation of platelets obtained from normal donors in the presence or absence of IA was measured by a modified cone-plate viscometer and shear-induced vWF binding was measured by quantitative flow cytometry with monoclonal antibody known to bind exclusively to the C-terminal domain of vWF (LJ-C3) directly labeled with fluorescein isothiocyanate (FITC). P-selectin surface expression was also measured by a similar method with FITC conjugated anti-P-selectin monoclonal antibody (WGA1).</p><p><b>RESULTS</b>Shear-induced platelet aggregation was inhibited by IA in a dose-dependent manner. The extent of aggregation decreased from (78.6 +/- 4.6)% in the absence of IA to (36.5 +/- 2.1)% in the presence of IA (3.3 mmol/L) (P < 0.0001, n = 9) with a high shear rate of 10800 s(-1). vWF binding and P-selectin expression were also inhibited by IA in a dose dependent manner. The number of binding FITC-LJ-C3 molecules increased after exposure of platelet-rich plasma to a high shear rate of 10800 s(-1) for 6 minutes, but this shear-induced increased binding platelet surface vWF molecules and P-selectin expression can be decreased in the presence of IA.</p><p><b>CONCLUSION</b>vWF binding and vWF mediated platelet activation, aggregation occurring under high shear rate were inhibited by IA. IA may be a unique antithrombotic drug inhibiting the vWF-GP Ibalpha interaction, and may thus facilitate drug design targeting arterial thrombosis.</p>