Discovery and repurposing of artemisinin.

Malaria is an ancient infectious disease that threatens millions of lives globally even today. The discovery of artemisinin, inspired by traditional Chinese medicine (TCM), has brought in a paradigm shift and been recognized as the "best hope for the treatment of malaria" by World Health Organization. With its high potency and low toxicity, the wide use of artemisinin effectively treats the otherwise drug-resistant parasites and helps many countries, including China, to eventually eradicate malaria. Here, we will first review the initial discovery of artemisinin, an extraordinary journey that was in stark contrast with many drugs in western medicine. We will then discuss how artemisinin and its derivatives could be repurposed to treat cancer, inflammation, immunoregulation-related diseases, and COVID-19. Finally, we will discuss the implications of the "artemisinin story" and how that can better guide the development of TCM today. We believe that artemisinin is just a starting point and TCM will play an even bigger role in healthcare in the 21st century.

[Platelet function tests and Chinese medicines with antiplatelet function:a review].

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.

Inhibition of Shear-Induced Platelet Aggregation by Xueshuantong via Targeting Piezo1 Channel-Mediated Ca2+ Signaling Pathway.

XueShuanTong (XST) comprising therapeutically active ginsenosides, a lyophilized extract of Panax notoginseng roots, is extensively used in traditional Chinese medicine to treat ischemic heart and cerebrovascular diseases. Our recent study shows that treatment with XST inhibits shear-induced thrombosis formation but the underlying mechanism remained unclear. This study aimed to investigate the hypothesis that XST inhibited shear-induced platelet aggregation via targeting the mechanosensitive Ca2+-permeable Piezo1 channel by performing platelet aggregation assay, Ca2+ imaging and Western blotting analysis. Exposure to shear at physiologically (1,000-2000 s-1) and pathologically related rates (4,000-6,000 s-1) induced platelet aggregation that was inhibited by treatment with GsMTx-4. Exposure to shear evoked robust Ca2+ responses in platelets that were inhibited by treatment with GsMTx-4 and conversely enhanced by treatment with Yoda1. Treatment with XST at a clinically relevant concentration (0.15 g L-1) potently inhibited shear-induced Ca2+ responses and platelet aggregation, without altering vWF-mediated platelet adhesion and rolling. Exposure to shear, while resulting in no effect on the calpain-2 expression in platelets, induced calpain-2-mediated cleavage of talin1 protein, which is known to be critical for platelet activation. Shear-induced activation of calpain-2 and cleavage of talin1 were attenuated by treatment with XST. Taken together, our results suggest that XST inhibits shear-induced platelet aggregation via targeting the Piezo1 channel to prevent Piezo1-mediated Ca2+ signaling and downstream calpain-2 and talin1 signal pathway, thus providing novel insights into the mechanism of the therapeutic action of XST on platelet aggregation and thrombosis formation.

Artemisinin-Ginkgo biloba extract combination therapy for Plasmodium yoelii.

Malaria remains a widespread life-threatening infectious disease, leading to an estimated 219 million cases and around 435,000 deaths. After an unprecedented success, the antimalarial progress is at a standstill. Therefore, new methods are urgently needed to decrease drug resistant and enhance antimalarial efficacy. According to the alteration of erythrocyte biomechanical properties and the immune evasion mechanism of parasites, drugs, which can improve blood circulation, can be chosen to combine with antimalarial drugs for malaria treatment. Ginkgo biloba extract (GBE), one of drug for vascular disease, was used to combine with artemisinin for Plasmodium yoelii therapy. Artemisinin-GBE combination therapy (AGCT) demonstrated remarkable antimalarial efficacy by decreasing infection rate, improving blood microcirculation and modulating immune system. Besides, the expression of invasion related genes, such as AMA1, MSP1 and Py01365, can be suppressed by AGCT, hindering invasion process of merozoites. This new antimalarial strategy, combining antimalarial drugs with drugs that improve blood circulation, may enhance the antimalarial efficacy and ameliorate restoration ability, proving a potential method for finding ideal compatible drugs to improve malaria therapy.

The Joint Effect of a Combination of Components From the Fruit of Crataegus pinnatifida Bge. Var. major N.E. Br. and the Root of Salvia miltiorrhiza Bge. With Exercises on Swimming in Focal Cerebral Infraction in Rat.

Background: In our previous study, we found that the combination of a traditional Chinese medicine (TCM) and swimming could prevent atherosclerosis through a synergistic interaction. However, whether the combined application of active components from the fruit of Crataegus pinnatifida Bge. Var. major N.E. Br. and the root of Salvia miltiorrhiza Bge. (CPSM) and swimming has been effective in the prevention and treatment of focal cerebral infraction remained unclear. This work aimed to conduct detailed investigation on the joint effects of CPSM extract with swimming on focal cerebral infraction in rats and its underlying mechanisms. Method: A photochemical method of the combination of Rose Bengal (RB) injection and cold-light source irradiation was performed to establish the rat focal cerebral thrombosis model. The pathological changes of the brain were observed by a DCP-7030 laser multifunction machine, and the protein levels of von Willebrand factor (vWF), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) were detected by Western blotting. Blood samples were collected to assay tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAI-1), endothelin-1 (ET-1), 6-keto-prostaglandin F1α (6-keto-PGF1α), and thromboxane B2 (TXB2). Finally, the gene expression of t-PA, PAI-1, and ICAM-1 in human umbilical vein endothelial cells (HUVECs) stimulated by tumor necrosis factor-α (TNF-α) was assayed via real-time (RT) quantitative PCR (qPCR). Results: The joint effects of CPSM extract and swimming demonstrated significant interactions, which including increased blood perfusion, increased serum t-PA and 6-keto-PGF1α, decreased serum PAI-1 and TXB2, decreased protein levels of vWF, VCAM-1 and ICAM-1, and decreased ICAM-1 gene expression. Conclusion: This research demonstrated that the combined therapy of CP and SM extracts with swimming could prevent focal cerebral infraction through interactions on the regulation of vascular endothelial functions and inflammatory factors. It stresses the promising effects of the drugs and shear stress of blood flow in prevention and treatment of thrombosis. The mechanism may be related to regulating the protein expression of vWF, VCAM-1, and ICAM-1, and downregulating the gene expression of ICAM-1.

The birth of artemisinin.

As the first-line antimalarial drugs, artemisinins gained wide acceptance after the emergence of resistance to chloroquine in the 1950s. Artemisinin-based drugs have saved lives, especially in developing countries. The discovery of artemisinin was unique, timely, and fascinating, and the benefits of artemisinin were with far-reaching implications. Herein, we will give a brief description of various aspects of the development of artemisinin and discuss the position and perspectives of artemisinin-based drugs.

[Effects of Xueshuantong Injection on thrombosis formation and blood flow in rats].

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.

Anti-thrombosis Effects and Mechanisms by Xueshuantong Capsule Under Different Flow Conditions.

Xueshuantong capsule (XST) is a patented traditional Chinese medicine used for the prevention and treatment of thrombosis. The molecular mechanism of anti-thrombotic effect of XST was investigated through the cross-talk among the platelets/leukocytes, endothelial cells (ECs), and flow shear stress. The Bioflux 1000 system was used to generate two levels of shear stress conditions: 0.1 and 0.9 Pa. Bioflux Metamorph microscopic imaging system was used to analyze the adhesion cell numbers. Protein expressions were detected by western blotting and flow cytometry. The flow-cytometry results showed that under 0.1 Pa flow, XST decreased ADP induced platelets CD62p surface expression in a concentration-dependent manner. Under 0.9 Pa flow, XST at a concentration of 0.15 g⋅L-1 reduced the platelets activation by 29.5%, and aspirin (ASA) showed no inhibitory effects. XST showed similar efficiency on monocytes adhesion both under 0.1 and 0.9 Pa flow conditions, and the inhibition rate was 30.2 and 28.3%, respectively. Under 0.9 Pa flow, the anti-adhesive effects of XST might be associated with the suppression of VE-cadherin and Cx43 in HUVECs. Blood flow not only acts as a drug transporter, but also exerts its effects to influence the pharmacodynamics of XST. Effects of XST on inhibiting platelets activation and suppressing platelets/leukocytes adhesion to injured ECs are not only concentration-dependent, but also shear stress-dependent. The mechanic forces combined with traditional Chinese medicine may be used as a precise treatment for cardiovascular diseases.

What has traditional Chinese medicine delivered for modern medicine?

The field of Traditional Chinese Medicine (TCM) represents a vast and largely untapped resource for modern medicine. Exemplified by the success of the antimalarial artemisinin, the recent years have seen a rapid increase in the understanding and application of TCM-derived herbs and formulations for evidence-based therapy. In this review, we summarise and discuss the developmental history, clinical background and molecular basis of an action for several representative TCM-derived medicines, including artemisinin, arsenic trioxide, berberine and Salvia miltiorrhiza or Danshen. Through this, we highlight important examples of how TCM-derived medicines have already contributed to modern medicine, and discuss potential avenues for further research.

[Development of bioassay method in quality control of traditional Chinese medicine].

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].

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.

Prevention of atherosclerosis by Yindan Xinnaotong capsule combined with swimming in rats.

BACKGROUND: Yindan Xinnaotong capsule has been used for treating cardio-cerebrovascular diseases for several decades in China. Exercise training can protect against the development of atherosclerosis. The aim of the present study is to evaluate the joint effect of YXC and exercise on atherosclerosis in rats. METHODS: A combined method involving low shear stress and a high-fat diet was used to establish the atherosclerosis model in rats. Partial ligation of the left common carotid artery was performed, and then the rats were divided into 9 treatment groups according to a 3 × 3 factorial design with two factors and three levels for each factor, swimming of 0, 0.5, 1 h daily and YXC administration of 0, 1, 2 g/kg p.o. daily. Next the interventions of swimming and YXC were executed for 8 weeks. After that, blood samples were collected to determine blood viscosity, plasma viscosity, haematocrit (HCT), fibrinogen (FIB), blood lipid profile (including total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), triglyceride (TG) and high-density lipoprotein-cholesterol (HDL-C)), nitric oxide (NO), 6-keto- prostaglandin (PG) F1α, endothelin (ET) and thromboxane (TX) B2. The common carotid arteries of the rats were harvested to examine pathological changes, wall thickness and circumference, and the expression of SM22αwas assayed via immune-histochemistry. RESULTS: The early pathological changes were observed. The joint effects of YXC and swimming showed significant changes in the examined parameters: (1) decreases in plasma viscosity, blood viscosity and FIB; (2) increases in NO and 6-keto-PGF1α; (3) decreases in ET and TXB2; and (4) decreases in LDL-C and TG. The combination of 2 g/kg YXC and 1 h of swimming led to synergistic decreases in LDL-C and TG. The interactive effect between YXC and swimming was obvious in decreasing wall thickness. Swimming alone was able to up-regulate the expression of SM22α. CONCLUSIONS: In conclusion, this study indicates that the combination of YXC and swimming may prevent atherosclerosis through a synergistic effect between YXC and swimming in improving blood circulation, hemorheological parameters, blood lipids levels and the vascular endothelium in rats. The vascular remodeling may be contributed to the prevention effects on AS by up-regulating SM22α.

[Anti-platelet aggregation bioassay based quality control for XST capsules].

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.

[Preliminary application of atomic force microscopy on identification of native habitat of Chinese medicine decoction pieces].

Identification of the native habitat of Chinese medicine decoction pieces plays an important role in the use of Chinese Heber medicine. However, the traditional method always based on subjective description, lack of quantitative information. In this study, nanomechanical analysis of Ophiopogonis Radix, Polygonati Odorati Rhizoma and Curcumae Aromaticae Radix coming from different districts was carried out by using the force-distance curve of atomic force microscopy (AFM), including stiffness (represented by the slope of the force curve) and adhesion work (calculated via the adhesion area of the retrace line in force-distance curve). The results showed that the Ophiopogonis Radix from Sichuan province (slope 0.03 +/- 0.001) was significantly stiffer but less sticky [adhesion work 393.98 +/- 49.21 x 10(-10)) J] in comparison with that from Hubei province [slope 0.018 +/- 0.001, adhesion work (985.67 +/- 91.61) x 10(-10) J]; the Polygonati Odorati Rhizoma Hunan province was stiffer (slope 0.03 +/- 0.002) and stickier [adhesion work (413.67 +/- 92.58) x10(-10) J] than that from Dongbei province [slope 0.019 +/- 0.002, adhesion work (27.37 +/- 11.05) x 10(-10) J]; the Curcumae Aromaticae Radix from Sichuan province was also stiffer (slope 0.019 +/- 0.0017) but less stickier [adhesion work (1179.79 +/- 225.05) x 10(-10) J] than that from Hubei province [slope 0.013 +/- 0.0006, adhesion work (2831.27 +/- 93.71) x 10(-10)]. It is indicated that changes in mechanical properties of Chinese medicine decoction pieces correlate well with their origin. This method may provide quantitative information for the identification of the native habitat of Chinese medicine decoction pieces.

Joint preventive effects of swimming and Shenlian extract on rat atherosclerosis.

This work is to investigate the joint effect of extract from Shenlian (SL, the Chinese abbreviation for Radix Salviae miltiorrhizae and Andrographis paniculata) and swimming on atherosclerosis prevention and treatment. Atherosclerotic rat model was established by combining low shear stress by partial ligation of common carotid artery with afterwards feeding of a hyperlipotic diet. Sprague-Dawley rats after partial ligation of common carotid artery were allotted to a 3 × 3 factorial design with three levels of swimming (0, 1, and 2 hr per day) and three levels of SL extract (0, 2.56, and 5.12 g/kg once daily p.o.) for a total of 9 treatment groups. Then, the feeding of the hyperlipotic diet and the intervention of swimming and SL started at the same time, and lasted for 8 weeks. By the end, blood samples were collected to determine blood viscosity, hematocrit, blood lipids, MCP-1, NF-κB and NO levels. The common carotid arteries of the rats were harvested to investigate pathological changes. The animal model showed early sign of atherosclerosis according to the pathological findings. Joint effects of SL extract and swimming on preventing atherosclerosis appeared significantly: The combination of 1 hour swimming with 2.56 g/kg SL extract showed to be effective for lowering hematocrit, blood viscosity (at 10 s(-1) and 200 s(-1)) and low-density-lipoprotein (p < 0.001). Combined treatment of 2.56 g/kg SL extract with 2 hr swimming led to a synergistic decrease in serum level of MCP-1. As a single factor, SL extract (2.56 g/kg) alone could decrease serum levels of NF-κB significantly (p = 0.003). Swimming alone could decrease cholesterol, triacylglycerols level and increase high-density-lipoprotein. The study demonstrates the combined therapy of oral SL extract with swimming on inhibiting inflammatory factors, improving hemorheological parameters and lipoproteins in rat model of atherosclerosis. It highlights the promising effects of the drugs and shear stress of blood flow, the biomechenopharmacological means, for prevention of atherosclerosis.

Total salvianolic acid improves ischemia-reperfusion-induced microcirculatory disturbance in rat mesentery.

AIM: To investigate the effect of total salvianolic acid (TSA) on ischemia-reperfusion (I/R)-induced rat mesenteric microcirculatory dysfunctions. METHODS: Male Wistar rats were randomly distributed into 5 groups (n = 6 each): Sham group and I/R group (infused with saline), TSA group, TSA + I/R group and I/R + TSA group (infused with TSA, 5 mg/kg per hour). Mesenteric I/R were conducted by a ligation of the mesenteric artery and vein (10 min) and subsequent release of the occlusion. TSA was continuously infused either starting from 10 min before the ischemia or 10 min after reperfusion. Changes in mesenteric microcirculatory variables, including diameter of venule, velocity of red blood cells in venule, leukocyte adhesion, free radicals released from venule, albumin leakage and mast cell degranulation, were observed through an inverted intravital microscope. Meanwhile, the expression of adhesion molecules CD11b/CD18 on neutrophils was evaluated by flow cytometry. Ultrastructural evidence of mesenteric venules damage was assessed after microcirculation observation. RESULTS: I/R led to multiple responses in mesenteric post-capillary venules, including a significant increase in the adhesion of leukocytes, production of oxygen radicals in the venular wall, albumin efflux and enhanced mast cell degranulation in vivo. All the I/R-induced manifestations were significantly reduced by pre- or post-treatment with TSA, with the exception that the I/R-induced increase in mast cell degranulation was inhibited only by pre-treatment with TSA. Moreover, pre- or post-treatment with TSA significantly attenuated the expression of CD11b/CD18 on neutrophils, reducing the increase in the number of caveolae in the endothelial cells of mesentery post-capillary venules induced by I/R. CONCLUSION: The results demonstrated that TSA protects from and ameliorates the microcirculation disturbance induced by I/R, which was associated with TSA inhibiting the production of oxygen-free radicals in the venular wall and the expression of CD11b/CD18 on neutrophils.

The antioxidant Cerebralcare Granule attenuates cerebral microcirculatory disturbance during ischemia-reperfusion injury.

Cerebralcare Granule (CG) is a compound Chinese medicine used for treatment of headache and dizziness associated with cerebrovascular diseases. To clarify the mechanism underlying the clinical outcome of CG, this study investigated the effects of CG on the structure and function of cerebral microvasculature during I/R injury. A total of 138 Mongolian gerbils were included and divided into four groups, each composed of 36 or 30 animals, for evaluating various parameters of concern. A skull window was prepared for microcirculatory observation in animals, which were subjected to I/R with or without pretreatment with CG (0.4 or 0.8 g/kg). The velocity of red blood cells in the venules was observed by a high-speed video camera system, along with intravital confocal microscopic measurements of microvascular diameters, adherent leukocytes, and albumin leakage in the brain cortex. Changes in the fluorescence intensity of dihydrorhodamine 123 in cerebral microvessels and malondialdehyde level in the cortex were measured. The ultrastructure of the microvessels in the cerebral cortex was analyzed using both transmission and scanning electron microscopy. In addition, cerebral blood flow was monitored using the laser Doppler imaging technique. Pretreatment with CG (0.4 or 0.8 g/kg) significantly alleviated I/R injury-induced disorders in cerebral microvasculature, as evidenced by the data observed at 60 min of reperfusion wherein the values in CG (0.4 g/kg) pretreatment group, CG (0.8 g/kg) pretreatment group, and I/R group were 2.43 +/- 0.24, 2.28 +/- 0.18, and 6.00 +/- 0.35 for leukocyte adhesion, 2.51 +/- 0.40, 2.33 +/- 0.29, and 4.77 +/- 0.24 for albumin leakage, 7.06 +/- 0.81, 5.93 +/- 0.42, and 28.38 +/- 2.70 for dihydrorhodamine 123 fluorescence intensity in cerebral microvessels, 16.35 +/- 0.52, 14.34 +/- 0.68, and 21.46 +/- 0.71 for malondialdehyde level in the cortex, and 0.43 +/- 0.07, 0.46 +/- 0.02, and 0.17 +/- 0.08 for cerebral blood flow, respectively. I/R injury-elicited ultrastructural alterations in microvessels in cerebral cortex were also mitigated impressively by CG administration, manifested as attenuation of the reduced number of opening capillaries and the altered fine structures in endothelium, which were characterized by rough inner surface, increased intracellular vesicles, hypertrophy of digitations of intercellular contact, and swollen perivascular astroglial processes. Cerebralcare Granule is able to attenuate I/R injury-induced functional and structural changes in microvessels in the cerebral cortex of gerbils, an ability that is most likely correlated with its antioxidant potential.

Improving effect of post-treatment with Panax notoginseng saponins on lipopolysaccharide-induced microcirculatory disturbance in rat mesentery.

Panax notoginseng saponin (PNS) is the collective of the major effective components of Panax notoginseng. The present study intended to explore the effect of post-treatment of PNS on rat mesentery microcirculatory disturbance induced by lipopolysaccharide (LPS) continuous challenge. By virtue of a microcirculation observation system, the vascular hemodynamics were determined continuously until 60 min of LPS (2 mg/kg/h) infusion through the left femoral vein. After observation, blood was taken for assessment of the expression of CD11b/CD18 in neutrophils and the concentration of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interferon-gamma (INF-gamma) in plasma with flow-cytometry. The number of leukocytes adherent to venular wall, the intensity of hydrogen peroxide dependent dihydrorhodamine 123 (DHR) fluorescence in the venular walls and albumin leakage from venules were increased impressively after 20 min of LPS infusion, the RBCs velocity diminished after 30 min, and degranulated mast cells increased remarkably after 60 min. Post-treatment with PNS (5 mg/kg/h) through the left jugular vein from 20 min of LPS exposure resulted in significant reduction in the number of adherent leukocytes, degranulation of mast cell, expression of CD11b and the concentration of IL-6, INF-gamma, while had no influence on the intensity of DHR fluorescence and albumin leakage. The results suggested that post-treatment with PNS significantly attenuated microcirculatory disturbance induced by LPS.

Protective effect of tetramethylpyrazine and salvianolic acid B on apoptosis of rat cerebral microvascular endothelial cell under high shear stress.

Apoptosis induced by high shear stress has been reported for the dysfunction of various vascular endothelial cells. We investigated the protective effects of tetramethylpyrazine (TMP) and salvianolic acid B (SAB) from Chinese medicine on the shear-induced early and late stages of apoptosis in cultured rat cerebral microvascular endothelial cells (rCMECs) under pathological high shear stress. Near-confluent cultures of rCMECs were pretreated with TMP or SAB and their combinational dosages, and exposed to high shear stress generated by a rheometer. Apoptotic death rate of rCMECs was assessed by immunofluorescence microscopy of Annexin V-FITC and propidium iodide (PI). We found that early and late stage apoptosis occurred at 3.0 Pa for a short duration of 450 sec but did not occur at 1.5 Pa. SAB inhibited the cells from apoptosis at concentrations from 10 microM to 20 microM in a dose-dependent manner, while effect of TMP at 0.37 mM and 0.73 mM did not significantly differ. Moreover, the combined use of TMP and SAB had synergistic anti-apoptotic effects (P<0.01). The results indicate that the anti-apoptotic effect of TMP and SAB on rheologically induced endothelial injury is likely involved in their efficacy.

Effect of notoginsenoside R1 on hepatic microcirculation disturbance induced by gut ischemia and reperfusion.

AIM: To assess the effect of notoginsenoside R1 on hepatic microcirculatory disturbance induced by gut ischemia/reperfusion (I/R) in mice. METHODS: The superior mesenteric artery (SMA) of C57/BL mice was ligated for 15 min to induce gut ischemia followed by 30-min reperfusion. In another set of experiments, R1 was continuously infused (10 mg/kg per hour) from 10 min before I/R until the end of the investigation to study the influence of R1 on hepatic microcirculatory disturbance induced by gut I/R. Hepatic microcirculation was observed by inverted microscopy, and the vascular diameter, red blood cell (RBC) velocity and sinusoid perfusion were estimated. Leukocyte rolling and adhesion were observed under a laser confocal microscope. Thirty and 60 min after reperfusion, lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate transaminase (AST) in peripheral blood were determined. The expression of adhesion molecules CD11b/CD18 in neutrophils and tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in plasma were evaluated by flow cytometry. E-selectin and intercellular adhesion molecule-1 (ICAM-1) in hepatic tissue were examined by immunofluorescence. RESULTS: After gut I/R, the diameters of terminal portal venules and central veins, RBC velocity and the number of perfused sinusoids were decreased, while the leukocyte rolling and adhesion, the expression of E-selectin in hepatic vessels and CD18 in neutrophils, IL-6, MCP-1, LDH, ALT and AST were increased. R1 treatment attenuated these alterations except for IL-6 and MCP-1. CONCLUSION: R1 prevents I/R-induced hepatic microcirculation disturbance and hepatocyte injury. The effect of R1 is related to its inhibition of leukocyte rolling and adhesion by inhibiting the expression of E-selectin in endothelium and CD18 in neutrophils.