L-3-n-butylphthalide improves cognitive deficits in rats with chronic cerebral ischemia

3-n-Butylphthalide (NBP) has been shown to have protective effects against ischemic stroke. In the present study, we investigated effects of l-3-n-butylphthalide (l-NBP) on the learning and memory impairment induced by chronic cerebral ischemia in rats. Male Wistar rats were administered 20 mg/kg l-NBP by gavage daily for 30 days after the bilateral common carotid artery clamping (two-vessel occlusion, 2-VO). Results showed that daily treatments of 20 mg/kg l-NBP significantly attenuated spatial learning deficits in Morris water maze (MWM) task. Results of long-term potentiation (LTP) indicated that treatment with 20 mg/kg l-NBP attenuated the inhibition of LTP in rat model of 2-VO. Moreover, l-NBP reduced glial fibrillary acidic protein (GFAP)-positive astrocytes induced by chronic cerebral ischemia. The present findings demonstrate the protective effect of l-NBP on chronic cerebral ischemia-induced hippocampus injury, which supports using l-NBP for therapy of cerebral ischemia in the future.     

Antiplatelet and antithrombotic effects of a novel selective phosphodiesterase 3 inhibitor, NSP-513, in mice and rats

We investigated the effects of NSP-513, (R)-4,5-dihydro-5-methyl-6-[4-(2-propyl-3-oxo-1-cyclohexenyl)amino] phenyl-3(2H)-pyridazinone, on phosphodiesterase (PDE) isozyme activities, in vitro platelet aggregation and in vivo thrombus formation. NSP-513 selectively inhibited human platelet PDE 3 isozyme with an IC50 value of 0.039 microM. In an in vitro human platelet aggregation assay, the IC50 values (microM) of NSP-513 for platelet aggregation induced by collagen, U-46619, arachidonic acid, adenosine diphosphate (ADP), epinephrine and thrombin were 0.31, 0.25, 0.082, 0.66, 0.23 and 0.73, respectively. In a mouse pulmonary thromboembolism model, orally administered NSP-513 showed in vivo antithrombotic effects that were 320 to 470 times more potent than those of cilostazol. In a rat carotid arterial thrombosis model, intraduodenally administered NSP-513 (0.1 mg/kg), cilostazol (30 mg/kg) and aspirin (30 mg/kg) reduced thrombus formation by 75%, 66% and 48%, respectively. However, intravenously administered dipyridamole (10 mg/kg) did not significantly prevent thrombus formation. These results demonstrate that NSP-513 has the potential to prevent not only in vitro platelet aggregation but also in vivo thrombus formation and indicate that the highly selective PDE 3 inhibitory effect of NSP-513 may make this compound useful for assessing the physiological role of PDE 3.     

Antiplatelet and antithrombotic activities of Korean Red Ginseng

The antiplatelet and antithrombotic activities of Korean Red Ginseng (KRG) were examined on rat carotid artery thrombosis in vivo, and platelet aggregation in vitro and ex vivo. Administration of KRG to rats not only prevented carotid artery thrombosis in vivo in a dose-dependent manner, but also significantly inhibited ADP- and collagen-induced platelet aggregation ex vivo, while failed to prolong coagulation times such as activated partial thromboplastin time (APTT) and prothrombin time (PT), indicating the antithrombotic effect of KRG might be due to its antiplatelet aggregation rather than anticoagulation effect. In line with the above observations, KRG inhibited U46619-, arachidonic acid-, collagen- and thrombin-induced rabbit platelet aggregation in vitro in a concentration-dependent manner, with IC50 values of 620 +/- 12, 823 +/- 22, 722 + 21 and 650 +/- 14 microg/mL, respectively. Accordingly, KRG also inhibited various agonists-induced platelet serotonin secretions as it suppressed platelet aggregation. These results suggest that KRG has a potent antithrombotic effect in vivo, which may be due to antiplatelet rather than anticoagulation activity, and KRG intake may be beneficial to the individuals with high risks of thrombotic and cardiovascular diseases.     

Antiplatelet and antithrombotic effect of D-003.

D-003 is a mixture of higher primary aliphatic saturated acids purified from sugar cane wax whose main component is octacosanoic acid followed by triacontanoic, dotriacontanoic, and tetratriacontanoic acids. The aim of this study was to evaluate the effects of D-003 on: ex vivo platelet aggregation, arterial thrombosis and bleeding time in rats. In addition, time course of antiplatelet effects of D-003 was also investigated on ex vivo platelet aggregation in guinea-pigs. D-003 (25-200 mg kg(-1)) orally administered at single or repeated doses (3 days) inhibited platelet aggregation induced by collagen (2.2 microg ml(-1)) and ADP (2 micromol l(-1)) in rats, and collagen (0.25 microg ml(-1)) induced aggregation in guinea-pigs in a dose-dependent manner. Single doses of D-003 (5-500 mg kg(-1)) administered orally 2 h before induction of arterial thrombosis significantly inhibited the reduction of rectal temperature. D-003 administered at a single dose (50-200 mg kg(-1)) 2 h before the experiment significantly increased the bleeding time in a dose-dependent manner. The time-course effects of D-003 on platelet aggregation, arterial thrombus formation, and bleeding time showed no effect 0.5 h after dosing, and maximal effects exhibited 1-2 h after treatment, whereas no significant effects were found 4 h after treatment.     

Long-term treatment of l-3-n-butylphthalide attenuated neurodegenerative changes in aged rats

It is shown that l-3-n-butylphthalide (l-NBP), the isomer of dl-NBP (racemic 3-n-butylphthalide, a new anti-cerebral ischemic agent) significantly attenuated cerebral hypoperfusion-induced learning dysfunction and brain damage in rats. In the present study, l-NBP (10 and 30 mg/kg) long-term (3-month) treatment of aged rat (21-month-old) significantly improved the learning and memory capability measured by the Morris water maze test. Hematoxylin–eosin-stained slices showed that both l-NBP at 30 mg/kg, and memantine as control at 20 mg/kg, attenuated the neurodegenerative changes in aged rats. l-NBP treatment significantly increased the choline acetyltransferase activity and dose-dependently decreased the acetylcholinesterases activity in the hippocampus of aged rats. The immunohistological study demonstrated that expressions of β-secretase and hyperphosphorylated tau protein were significantly increased in the hippocampus CA1 subfield and parietal cortex in aged rats. However, they were decreased significantly by treatment of l-NBP and memantine for 3 months. Our results indicated that long-term treatment with l-NBP might prevent age-related neurodegenerative changes by modulation of cholinergic system, reduction of phosphorylated tau and maintain structure and morphology of neurons. Therefore, l-NBP might be a potential drug for treatment of senile dementia.     

Distribution and metabolism of L-3-O-methyldopa in rats

1. After intraperitoneal administration of L-2-(14)C-3-O-methyldopa ((14)C-O-methyldopa) to rats, the amino-acid was distributed evenly in blood, brain, heart, adipose tissue and liver, whereas it accumulated more in the kidney and the pancreas. (14)C-O-methyldopa showed a biological half-life of about 12-13 h in blood, brain and heart.2. The concentration curve of (14)C-O-methyldopa in brain (after increasing doses of the amino-acid) was linear if measured 2 h after administration, but seemed to reach a plateau at the higher doses if determined after 16 h.3. The concentrations of (14)C-O-methyldopa metabolites (mainly homovanillic acid and 4-hydroxy-3-methoxyphenyllactic acid) were low, except in the kidney, and varied according to the tissue.4. Twenty-four hours after administration of (14)C-O-methyldopa, 33% of the injected radioactivity appeared in the urine. This radioactivity consisted of about 95% of metabolites (probably in the main (14)C-homovanillic acid and (14)C-4-hydroxy-3-methoxyphenyllactic acid) and of 5% of unchanged (14)C-O-methyldopa. In the faeces, 10% of the radioactivity appeared, mainly as metabolic end-products.5. It is concluded that (14)C-O-methyldopa easily penetrates from the blood into various tissues, including brain, and that the majority of the amino-acid undergoes a slow metabolism. The different shape of the concentration curves for (14)C-O-methyldopa in the brain after 2 and 16 h might indicate the presence of two tissue pools of the amino-acid.     

Antiplatelet and antithrombotic activities of timosaponin B-II, an extract of Anemarrhena asphodeloides

1. Antithrombotic agents are effective in the treatment of ischaemic stroke. Timosaponin B-II (TB-II) is a major active component of Anemarrhena asphodeloides Bunge (Liliaceae; rhizome) that has protective effects against cerebral ischaemic damage. The present study examined the antiplatelet and antithrombotic actions of TB-II. 2. In in vitro experiments, TB-II (20, 40 and 80 mg/mL) potently and dose-dependently inhibited ADP-induced platelet aggregation. Furthermore, 1, 3 and 6 mg/kg TB-II prolonged activated partial thromboplastin time by 9.29, 16.86 and 25.50%, respectively, but had no effect on the prothrombin time. Furthermore, 1, 3 and 6 mg/kg TB-II significantly reduced the wet weight, dry weight and length of the thrombi (%inhibition (based on wet weight): 13.6, 19.8 and 24.7%, respectively). 3. In a rabbit arteriovenous shunt model, 1, 3 and 6 mg/kg, i.v., TB-II had no effect on thrombus formation. Plasma euglobulin lysis time and fibrin degradation product were not affected by 1, 3 and 6 mg/kg TB-II, but plasminogen levels were decreased significantly by 14.4, 18.3 and 29.0%, respectively. 4. The results of the present study demonstrate significant antiplatelet and anticoagulation effects of TB-II and suggest that these actions could contribute to its neuroprotective effect against damage following cerebral ischaemia damage.     

丁基苯酞对局部脑缺血大鼠记忆障碍的影响

观察了丁基苯酞（ＮＢＰ）对局部脑缺血大鼠记忆障碍的影响．用穿梭箱进行学习记忆获得性训练，以主动回避反应潜伏期和次数以及逃避反应潜伏期为指标，评价大脑中动脉阻断（ＭＣＡＯ）后记忆保持的能力．结果表明：假手术组的记忆功能与正常组没有显著差别，而缺血对照组大鼠主动回避反应次数减少６０％，主动回避和逃避反应潜伏期分别较缺血前延长４．２±１．６和４．１±３．３ｓ．给ＮＢＰ３０和１００ｍｇｋｇ－１后主动回避反应的次数明显提高，主动回避反应潜伏期明显缩短，与缺血对照组比较均有非常明显的差别．表明ＮＢＰ对局部脑缺血引起的记忆障碍有明显改善作用．     

Inhibitory effects of chiral 3-n-butylphthalide on inflammation following focal ischemic brain injury in rats

AIM: To evaluate the degree of neutrophil infiltration into ischemic tissue after transient focal cerebral ischemia, and to examine the effects of chiral 3-n-butylphthalide (NBP) on this inflammatory process. METHODS: After a 24-h reperfusion following transient cerebral ischemia, two different techniques, histologic analysis and modified myeloperoxidase (MPO)-quantification method, were utilized to identify the infiltration of neutrophils into cerebral tissue following ischemia. The expression of intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-alpha(TNF-alpha) in the ischemic zone were observed by immunohistochemistry, Western blot, and in situ hybridization techniques. RESULTS: In cerebral cortex area perfused by middle cerebral artery (MCA), MPO activity was greatly increased after 24 h of reperfusion in the vehicle group, and it correlated well with the infiltration of neutrophils. Administration of dl-, d-, and l-NBP (20 mg.kg-1) partially inhibited both the increase in MPO activity and the appearance of neutrophils in ischemia-reperfusion sites. Up-regulation of ICAM-1 was also observed on the microvessel endothelium in the ischemic territory. In addition, chiral NBP markedly blunted ICAM-1 expression, and decreased the number of TNF-alpha blue purple-positive neurons induced by ischemia-reperfusion injury. CONCLUSION: The results indicate that the increase in neutrophils infiltration into the infarct site implicated postischemic brain injury, and NBP was effective in protecting the ischemic sites following ischemic insult.     

手性3-n丁基苯酞对大鼠局灶性脑缺血诱导的凋亡的影响

目的:观察和比较手性3-n丁基苯酞(NBP)对大鼠局灶性脑缺血再灌注诱导的凋亡的影响。方法:插线法制备大脑中动脉阻断(MCAO)模型,原位末端标记(TUNEL)和琼脂糖凝胶电泳检测DNA断裂,蛋白质印迹和免疫组化方法检测细胞色素c及caspase-3蛋白的表达。结果:大鼠局灶性脑缺血2小时,再灌注开始后24小时可见明显的TUNEL阳性染色和DNA ladder.s-(-)-NBP 5,10 mg/kg显著减少TUNEL阳性细胞数和DNA ladder,s-(-)-NBP 10 mg/kg几乎完全抑制DNA片段化,而r-(+)-NBP 10 mg/kg仅有轻度抑制作用。(±)-NBP(20 mg/kg)对DNA片段化的抑制作用介于s-(-)-NBP(10 mg/kg)和r-(+)-NBP(10 mg/kg)之间。脑缺血过程中可见到线粒体细胞色素c的释放及caspase-3的激活,s-(-)-NBP能明显抑制这一效应,r-(+)-NBP和(±)-NBP对细胞色素c和caspase-3作用的强弱与它们抑制DNA片段化的作用强度相似。结论:NBP,尤其是s-(-)-NBP能够抑制脑缺血诱导的DNA片段化,细胞色素c释放和caspase-3激活。     

The edaravone and 3-n-butylphthalide ring-opening derivative 10b effectively attenuates cerebral ischemia injury in rats

Aim:

Compound 10b is a hybrid molecule of edaravone and a ring-opening derivative of 3-n-butylphthalide (NBP). The aim of this study was to examine the effects of compound 10b on brain damage in rats after focal cerebral ischemia.

Methods:

SD rats were subjected to 2-h-middle cerebral artery occlusion (MCAO). At the onset of reperfusion, the rats were orally treated with NBP (60 mg/kg), edaravone (3 mg/kg), NBP (60 mg/kg)+edaravone (3 mg/kg), or compound 10b (70, 140 mg/kg). The infarct volume, motor behavior deficits, brain water content, histopathological alterations, and activity of GSH, SOD, and MDA were analyzed 24 h after reperfusion. The levels of relevant proteins in the ipsilateral striatum were examined using immunoblotting.

Results:

Administration of compound 10b (70 or 140 mg/kg) significantly reduced the infarct volume and neurological deficits in MCAO rats. The neuroprotective effects of compound 10b were more pronounced compared to NBP, edaravone or NBP+edaravone. Furthermore, compound 10b significantly upregulated the protein levels of the cytoprotective molecules Bcl-2, HO-1, Nrf2, Trx, P-NF-κB p65, and IκB-α, while decreasing the expression of Bax, caspase 3, caspase 9, Txnip, NF-κB p65, and P-IκB-α.

Conclusion:

Oral administration of compound 10b effectively attenuates rat cerebral ischemia injury.     

丁苯酞对db/db小鼠学习记忆及海马NR2B受体的影响

目的 观察丁苯酞对2型糖尿病db/db小鼠学习记忆及海马N-甲基-D-天冬氨酸受体2B亚基(NR2B)表达的影响,探讨丁苯酞改善糖尿病认知功能障碍的机制.方法 将16只db/db小鼠按随机数字表法分为丁苯酞干预组(L-NBP组,n=8)和糖尿病对照组(DM组,n=8),同窝出生的db/m小鼠作为正常对照组(NC组,n=10).适应性喂养1周后,L-NBP组每日以溶于植物油中的丁苯酞灌胃,剂量为120 mg·kg-1,DM组与NC组则给予同等剂量的植物油灌胃,干预6周后,进行指标观察.应用Morris水迷宫检测小鼠的学习记忆能力.实时荧光定量PCR检测NR2B mRNA的表达情况.结果 与NC组比较,DM组小鼠逃避潜伏期延长和平均探索次数减少(P＜0.05),而L-NBP组小鼠较DM组上述学习记忆成绩明显改善(P＜0.05);与NC组相比,DM组和L-NBP组小鼠海马CA1区NR2B mRNA表达水平明显下降(P＜0.05),而L-NBP组较DM组NR2B mRNA表达水平明显增高(P＜0.05).结论 丁苯酞可改善糖尿病引发的认知功能障碍,推测其机制可能与上调海马NP,2B的表达有关.     

莽草对大鼠大脑中动脉血栓所致局部脑缺血性损伤的拮抗作用

目的：研究莽草酸（ＳＡ）对大脑中动脉血栓所致局部脑缺血的影响。方法：用三氯化铁局部涂抹损伤血管形成的大鼠大脑中动脉血栓模型（ＭＣＡＴ）观察ＳＡ对行为障碍程度、脑梗塞范围、脑水肿和缺血区脑血流的影响。结果：ＳＡ２５、５０ｍｇ．ｋｇ＾－１ｉｐ于ＭＣＡＴ前连续红药３ｄ可分涉及了梗塞范围５１％、４２％,使脑含水量由８０．７％降致７９．８％、７９．９％,并可改善行为障碍程度和缺血区脑血流量的降低,病理检查显     

Antiplatelet and antithrombotic activities of NQ301, 2-chloro-3-(4-acetophenyl)-amino-1,4-naphthoquinone

The antiplatelet and antithrombotic activities of a newly synthesized NQ301, 2-chloro-3-(4-acetophenyl)-amino-1,4-naphthoquinone, were investigated on human platelet aggregation in vitro and rats ex vivo, and murine pulmonary thrombosis in vivo. NQ301 potently inhibited ADP-, collagen-, epinephrine- and calcium ionophore A23187-induced human platelet aggregation in a concentration-dependent manner in vitro. NQ301 significantly inhibited platelet aggregation in orally administered rats ex vivo. NQ301 prevented death due to pulmonary thrombosis in mice dose-dependently in vivo. NQ301 also showed significant prolongation of tail bleeding time in conscious mice. However, NQ301 did not alter such coagulation parameters as activated partial thromboplastin time, prothrombin time, and thrombin time in human plasma. These results suggest that NQ301 may be a promising antithrombotic agent, and the antithrombotic activity of NQ301 may be due to antiplatelet aggregation activity but not to in vitro anticoagulation.     

基苯酞改善大鼠实验性蛛网膜下腔出血后局部脑血流

目的：探讨丁基苯酞对大鼠蛛网膜下腔出血的可能治疗作用。方法；侧脑室注射自体动脉血造成多膜下腔出血模型，氢清除法测定尾核局部脑血流。结果：蛛网膜下腔出血后１５ｍｉｎ，ｒＣＢＦ即快速降至注血前的５２％，并且在１８０ｍｉｎ内基本上维持在该水平。     

Antiplatelet and antithrombotic activities of CP201, a newly synthesized 1,4-naphthoquinone derivative

The antiplatelet and antithrombotic activities of a newly synthesized CP201, 2-(3,5-di-tert-butyl-4-hydroxyl)-3-chloro-1,4-naphthoquinone on human platelet aggregation in vitro and murine pulmonary thrombosis in vivo were examined. In addition, the antiplatelet activity of CP201 involved in calcium-signaling cascade was also investigated. CP201 showed concentration-dependent inhibitory effects on platelet aggregation induced by collagen and thrombin, with IC50 values of 4.1+/-0.3 and 4.6+/-0.4 microM, respectively. Orally administered CP201 protected mice against the collagen plus epinephrine-induced thromboembolic death in a dose-dependent manner. On the other hand, CP201 did not alter such coagulation parameters as activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) in human plasma in vitro. These results suggest that the antithrombotic activity of CP201 may be due to antiplatelet rather than anticoagulation activity. CP201 potently inhibited platelet aggregation challenged by calcium ionophore A23187 and thapsigargin, which is a selective inhibitor of the Ca(2+)-ATPase pump, in a concentration-dependent manner, indicating that CP201 may have an inhibitory effect on calcium-signaling cascade. This was supported by measuring [Ca2+]i in platelets loaded with fura-3AM, where CP201 inhibited the rise in cytosolic Ca2+ mediated by thrombin. Taken together, these results suggest that CP201 may be a promising antithrombotic agent, and the antithrombotic effect of CP201 may be due to antiplatelet activity, which was mediated, at least partly, by the inhibition of cytosolic calcium mobilization.     

Passive targeting and lung tolerability of enoxaparin microspheres for a sustained antithrombotic activity in rats

Pulmonary bed can retain microparticles (MP) larger than their capillaries’ diameter, hence we offer a promising way for lung passive targeting following intravenous (IV) administration. In this study, enoxaparin (Enox)-albumin microspheres (Enox-Alb MS) were, optimally, developed as lung targeted sustained release MP for IV use. Lung tolerability and targeting efficiency of Enox-Alb MS were tested, and the pharmacokinetic profile following IV administration to albino rats was constructed. In vivo studies confirmed high lung targeting efficiency of Enox-Alb MS with lack of potential tissue toxicity. The anticoagulant activity of the selected Alb MS was significantly sustained for up to 38?h compared to 5?h for the market product. Alb MS are promising delivery carriers for controlled and targeted delivery of Enox to the lungs for prophylaxis and treatment of pulmonary embolism.     

丁基苯酞对正常及局部脑缺血大鼠纹状体脑血流影响

应用氢清除法连续测定大鼠一侧纹状体脑血流量(rCBF), 并观察丁基苯酞(NBP)对其影响. 结果表明, NBP 40或80 mg·kg^-1 ig均能显著增加大脑中动脉阻断后纹状体的rCBF(与溶剂对照组相比P<0.01), 作用持续3 h. 此外, 5-20 mg·kg^-1 ig时, 也可增加正常大鼠纹状体脑血流, 各剂量组NBP对平均动脉压均无明显影响; 尼莫地平(Nim)0.5 mg·kg^-1 ip也能明显增加纹状体脑血流, 同时轻度降低动脉平均压, 其增加脑血流作用与NBP 5 mg·kg^-1的作用相当. 提示NBP不仅能增加正常大鼠纹状体的脑血流, 还能增加大脑中动脉阻断后纹状体的血流量, 其抗脑缺血作用可能与该作用有关.     

Effects of dl-3-n-butylphthalide on region al cerebral blood flow in right middle cerebral artery occlusion rats

目的：观察ｄｌ３ｎ丁基苯酞（ＮＢＰ）对右大脑右中动脉阻断（ＲＭＣＡＯ）大鼠缺血区局部脑血流（ｒＣＢＦ）的影响．方法：氢清除法动态监测ＲＭＣＡＯ大鼠ｒＣＢＦ变化．结果：ＲＭＣＡＯ后１０ｍｉｎｉｐＮＢＰ（５，１０，２０ｍｇ·ｋｇ－１）可明显增加ｒＣＢＦ（与溶剂对照组相比Ｐ＜００１），４０ｍｉｎ给药有类似作用但作用较弱（与给药前相比Ｐ＜００５），６０ｍｉｎ给药不能增加ｒＣＢＦ（与给药前相比Ｐ＞００５）．此外，ＲＭＣＡＯ前４０ｍｉｎｉｐＮＢＰ也可使ＲＭＣＡＯ后不同时间点ｒＣＢＦ明显增加．尼莫地平（０５ｍｇ·ｋｇ－１，ｉｐ）与ＮＢＰ（１０ｍｇ·ｋｇ－１，ｉｐ）具有相似的作用．结论：ＮＢＰ预防给药或治疗给药能使ＲＭＣＡＯ后减少的ｒＣＢＦ明显增加．     

Antiplatelet and antithrombotic effects of the diterpene spiramine Q from Spiraea japonica var. incisa

Spiramine Q, a diterpene, was isolated from a Chinese herbal plant Spiraea japonica var. incisa Yu. Born's and Wan HY's methods were used to investigate effects of spiramine Q on rabbit platelet aggregation and serotonin release, respectively. Its antithrombotic effect in mice was also evaluated by Myers' method. Spiramine Q selectively inhibited arachidonic acid-induced platelet aggregation in vitro or ex vivo, and decreased serotonin secretion from rabbit platelets. Spiramine Q (5 mg/kg) decreased the mouse mortality caused by injection of 80 mg/kg arachidonic acid in the tail vein. The results suggested that spiramine Q showed potent antiplatelet and antithrombotic activites.