Guava leaf extract and topical haemostasis

The effects of guava leaf extract on the bleeding time and the three main mechanisms of haemostasis: vasoconstriction, platelet aggregation and blood coagulation, were investigated. The water extract of guava leaves did not shorten bleeding times in rats. Guava leaf extract potentiated the vascular muscle contraction induced in rabbits by phenylephrine, and when given alone it stimulated human platelet aggregation in vitro in a dose-dependent manner. On the other hand, it significantly prolonged blood coagulation; activated partial thromboplastin time (APTT) test (p < 0.05). The higher the concentration of the extract, the longer APTT was observed. Thus, a water extract of guava leaves showed ambiguous effects on the haemostatic system. Guava leaf extract did not affect bleeding times, it stimulated vasoconstriction and platelet aggregation but it inhibited blood coagulation. Therefore, guava leaf extract is not recommended as a haemostatic agent.     

Effect of guava (Psidium guajava Linn.) leaf soluble solids on glucose metabolism in type 2 diabetic rats

This study investigated the effect of aqueous and ethanol soluble solid extracts of guava (Psidium guajava Linn.) leaves on hypoglycemia and glucose metabolism in type 2 diabetic rats. Low-dose streptozotocin (STZ) and nicotinamide were injected into Sprague-Dawley (SD) rats to induce type 2 diabetes. Acute and long-term feeding tests were carried out, and an oral glucose tolerance test (OGTT) to follow the changes in plasma glucose and insulin levels was performed to evaluate the antihyperglycemic effect of guava leaf extracts in diabetic rats.The results of acute and long-term feeding tests showed a significant reduction in the blood sugar level in diabetic rats fed with either the aqueous or ethanol extract of guava leaves (p < 0.05). Long-term administration of guava leaf extracts increased the plasma insulin level and glucose utilization in diabetic rats. The results also indicated that the activities of hepatic hexokinase, phosphofructokinase and glucose-6-phosphate dehydrogenase in diabetic rats fed with aqueous extracts were higher than in the normal diabetic group (p < 0.05). On the other hand, diabetic rats treated with the ethanol extract raised the activities of hepatic hexokinase and glucose-6-phosphate dehydrogenase (p < 0.05) only. The experiments provided evidence to support the antihyperglycemic effect of guava leaf extract and the health function of guava leaves against type 2 diabetes.     

Chronic diuretic effect of the water extract of Spergularia purpurea in normal rats

The purpose of this study was to examine the chronic diuretic effect of the water extract of the whole plant of Spergularia purpurea (SP) at different doses (100, 200 and 400 mg/kg) in normal rats. Daily oral administration of the water extract was tested for 4 weeks. Urinary water and electrolytes excretion were determined weekly. Oral administration of the water extract at different doses produced a significant and dose-dependent diuresis and increase in electrolytes excretion. The highest dose (400 mg/kg) of the water extract of SP enhanced urine output from 7.15 +/- 0.42 ml/24 h at the start to 23.01 +/- 0.75 ml/24 h after 4 weeks (p < 0.001). It also produced significant increase in urinary excretion of Na+ (P < 0.01), K+ (P < 0.01) and Cl(-) (P < 0.01). Chronic treatment with SP decreased significantly urine osmolality (P < 0.01 vs. control), while a slight increase in glomerular filtration rate was also observed (P < 0.05) for both doses of water extract (100 and 400 mg/kg). It is concluded that the water extract of whole plant of SP has a significant diuretic effect in rats.     

In vivo evaluation of the anti-asthmatic,antitussive and expectorant activities of extract and fractions from Elaeagnus pungens leaf

The leaf of Elaeagnus pungens thunb. (Family Elaeagnaceae) has been documented as an effective herb for the treatment of asthma and chronic bronchitis in traditional Chinese medicine. This study was aimed at evaluating the anti-asthmatic, antitussive and expectorant activities in vivo of the ethanolic extract and fractions from the leaf of Elaeagnus pungens. The results showed that the 70% ethanolic extract increased the preconvulsive time of asthma induced by the combination of histamine and acetylcholine chloride in guinea pigs at the medium dose of 1.379 g/kg. The water fraction significantly prolonged the preconvulsive time (P < 0.05) in guinea pigs, lengthened the latent period of cough (P < 0.05) as well as decreased the cough frequency caused by citric acid in guinea pigs (P < 0.01) and enhanced tracheal phenol red output in mice (P < 0.01). Moreover, the petroleum ether fraction significantly reduced the cough frequency induced in guinea pigs (P < 0.01) and improved tracheal phenol red output in mice (P < 0.01). It indicated that the petroleum ether fraction and the water fraction of Elaeagnus pungens leaf were effective on anti-asthmatic, antitussive and expectorant activities, which supplied for further research on chemical constituents and pharmacological mechanisms.     

番石榴叶提取物调节白色脂肪组织棕色化作用机制研究

目的:探究番石榴叶提取物调节脂肪细胞分化的作用机制。方法:6周龄雄性SPF级db/db小鼠24只、同龄C57BL/6J正常组小鼠6只,将符合纳入标准的db/db小鼠根据体重、血糖随机分为模型组和番石榴叶提取物高剂量组、番石榴叶提取物中剂量组、番石榴叶提取物低剂量组,并将番石榴叶提取物按高、中、低剂量进行灌胃,于4周后空腹脱臼处死所有小鼠,分别取后腿腓肠肌组织、皮下脂肪组织进行原代成肌细胞、原代脂肪组织SVF细胞的培养、接种和传代。培养48 h后收集细胞并提取蛋白,Western blot法检测各组成肌细胞PGC-1α、FNDC5蛋白和各组脂肪组织SVF细胞Prdm16蛋白的表达。结果:第4周时,与模型组小鼠相比,番石榴叶提取物高剂量组小鼠体重、血糖、低密度脂蛋白降低(均P<0.05)。番石榴叶提取物高剂量组小鼠成肌细胞PGC-1α、FNDC5蛋白表达升高,脂肪组织SVF细胞Prdm16蛋白表达较模型组升高(均P<0.05)。结论:番石榴叶提取物高剂量可通过促进白色脂肪细胞向棕色脂肪细胞分化,提高棕色脂肪水平,从而通过增加机体的能量代谢来调节脂质代谢。     

Curry leaf (Murraya koenigii Spreng.) reduces blood cholesterol and glucose levels in ob/ob mice

We observed that curry leaf (Murraya koenigii) extract possesses the property to decrease blood cholesterol and blood glucose levels in diabetic ob/ob mice. Mice received daily intraperitoneal injections of 80 mg/kg curry leaf extract for 10 consecutive days. The extract significantly decreased blood cholesterol level from 277.6 +/- 16.6 mg/d (day 0) to 182.0 +/- 15.3 mg/d (day 10, p < 0.01 compared with the change in vehicle group). The extract also significantly decreased blood glucose level from 387.0 +/- 15.6 mg/dl (day 0) to 214.0 +/- 26.6 mg/dl (day 10, p < 0.01). In addition, body weight was reduced after extract treatment. Our data suggest that curry leaf may be proved to be of clinical importance in improving the management of high cholesterol level and type 2 diabetes.     

不同产地桔梗镇咳祛痰作用比较研究

目的：比较全国桔梗主产区不同产地桔梗的镇咳祛痰作用,为客观评价桔梗质量和种植生产提供参考依据。方法：采用浓氨水喷雾致咳实验、小鼠气管酚红排泄实验,观察不同产地桔梗水提物对小鼠咳嗽和气管分泌物的影响。结果：内蒙赤峰产桔梗药材最低镇咳、祛痰有效剂量为0.2 g·kg^-1,在此给药剂量下,内蒙赤峰产桔梗可显著减少小鼠咳嗽次数（P<0.01）,并可显著延长小鼠咳嗽潜伏期（P<0.01）,四川、陕西商州、重庆产桔梗可明显减少小鼠咳嗽次数（P<0.05）,四川、陕西商州、内蒙赤峰产桔梗可明显增加小鼠酚红排泄量（P<0.05）。结论：桔梗具有明显镇咳、祛痰作用,内蒙赤峰产桔梗镇咳、祛痰作用明显强于其它产地桔梗。     

Memory retrieval improvement by Ptychopetalum olacoides in young and aging mice

Amazonian peoples use traditional remedies prepared with Ptychopetalum olacoides (PO) roots for treating various age-related conditions. This study shows that a single intraperitoneally (i.p.) administration of Ptychopetalum olacoides ethanol extract (POEE, 50 and 100mg/kg) improved memory retrieval in step-down inhibitory avoidance (P 相似文献   

Neurosedative and muscle-relaxant activities of ethyl acetate extract of Baphia nitida AFZEL

The sedative, anxiolytic and muscle-relaxant effects of the ethyl acetate leaf extract of Baphia nitida (BN) was investigated in intact mice, using the hole-board head-dip test for exploratory behavioural effect, elevated plus maze (EPM) and Y-maze (YM) models of anxiety; chimney, inclined screen, traction and climbing tests for muscle-relaxant effects. In each of these tests, BN (100-400mg/kg, p.o.), diazepam (1mg/kg, i.p.) or distilled water (10ml/kg, p.o.) was administered, 30 or 60min before performing the tests in mice. For exploratory behavioural test, number of head-dip within 15min was counted. For EPM and YM tests, the cumulative time spent in open and closed arms was recorded within 5min. In the muscle-relaxant tests, mice were subjected to modified models such as chimney, inclined screen, traction and climbing tests. BN produced a significant (P<0.05) dose-related decrease in exploratory behaviour in the head-dip test and prolongation of cumulative time spent in open arms of both EPM and YM. BN did not show any significant effect in the chimney and traction tests, but produced significant, dose-dependent muscle relaxation in the inclined screen and climbing tests. Furthermore, BN (200-1200microg/ml) non-competitively shifted the curves of acetylcholine contractions of the toad Rectus abdominis muscle to the right. Oral doses of BN (0.1-20g/kg) did not produce mortality, but the LD(50) when given intraperitoneally, was 645.65mg/kg. Results suggest that the leaf extract of Baphia nitida has sedative, anxiolytic and skeletal muscle-relaxant effects and support its neurosedative use in traditional African medicine.