Diuretic and antidiuretic diuretic of the leaf extracts of Vernonia cinerea (Less) (Fam. Compositae)

The diuretic and anti-diuretic potency of the leaf extracts of Vernonia cinerea was studied in albino rats. The chloroform extract of the leaf induced significant diuresis, while the methanol and aqueous extracts induced significant antidiuresis in rats. In both cases, the observed effects on urine volume and electrolyte excretion were dose dependent. The trend was a significant increase (in the case of diuresis) in natriuretic and kaliuretic activity and a significant decrease (in the case of antidiuresis) in natriuresis and kaliuresis. © 1997 John Wiley & Sons, Ltd.     

A new method to increase selectivity of transglutaminase mediated PEGylation of salmon calcitonin and human growth hormone

Modification of therapeutic proteins and peptides by polyethylene glycol (PEG) conjugation is a well-known approach to improve the pharmacological properties of drugs. Several chemical procedures of PEG coupling are already in use but an alternative method based on microbial transglutaminase (mTGase) was recently devised. The enzyme catalyzes the link of mPEG-NH₂ to glutamines (Gln) of a substrate protein. In this case the advantage resides in the fact that usually only few Gln(s) in a protein are substrate of mTGase. In order to further restrict the selectivity of the enzyme, we investigated a new approach leading to the formation of a single conjugate isomer as well as for those proteins containing two or more Gln(s) as mTGase substrates. It was found that the addition of co-solvents in the reaction mixture influenced both the secondary structure of the targeted protein and the mTGase activity. The enzymatic PEGylation under these conditions yielded only mono- and selectively modified conjugates. The method was investigated with salmon calcitonin (sCT) and human growth hormone (hGH). In the case of sCT we also demonstrated the importance of site-selective conjugation for the preservation of in vivo activity.     

Anti-mycobacterial diynes from the Canadian medicinal plant Aralia nudicaulis

Ethnopharmacological relevance

Aralia nudicaulis, or wild sarsaparilla, is used as a traditional medicinal plant for the treatment of various illnesses by many of the Canadian First Nations. Iroquois and Algonquin First Nations of Eastern Canada use a tea prepared from dried Aralia nudicaulis rhizome as a cough medicine and for the treatment of tuberculosis. Previous investigations of aqueous extracts of Aralia nudicaulis rhizomes have shown it to possess antimycobacterial activity.

Aim of the study

To isolate and identify antimycobacterial constituents from Aralia nudicaulis rhizomes.

Materials and methods

Methanolic extracts of Aralia nudicaulis rhizomes were subjected to bioassay guided fractionation using the microplate resazurin assay (MRA) to assess inhibitory activity against Mycobacterium tuberculosis strain H37Ra. The antimycobacterial constituents were identified by NMR, MS and polarimetry.

Results

Two C17 polyacetylenes with significant antimycobacterial activity were isolated from the Aralia nudicaulis rhizome extract. The polyacetylenes were identified as (3R)-falcarinol and (3R, 9R, 10S)-panaxydol. Falcarinol and panaxydol displayed MICs of 25.6 μM and 36.0 μM and IC₅₀s of 15.3 μM and 23.5 μM against Mycobacterium tuberculosis H37Ra.

Conclusions

Falcarinol and panaxydol were identified as the principal constituents responsible for the antimycobacterial activity of Aralia nudicaulis rhizomes validating an ethnopharmacological use of this plant by the Canadian First Nations.     

Hepatoprotective effect of Filipendula hexapetala Gilib. (Rosaceae) in carbon tetrachloride-induced hepatotoxicity in rats

The influence of methanol extract produced from the flowers of Filipendula hexapetala Gilib. (Rosaceae) on some liver biochemical parameters in rats intoxicated with carbon tetrachloride (CTC) was evaluated in this study. The results Obtained revealed that pretreatment with the extract investigated inhibited CTC-induced liver injury by decreasing lipid peroxidation and increasing the content of reduced glutathione in a dosage dependent manner, bringing the levels of all antioxidant enzymes close to control values. The administration of CTC diminished hepatic antioxidant defense mechanisms by significant reduction of peroxidase and catalase activities. The catalase activity was significantly recovered in groups treated with the extract investigated and intoxicated with a single CTC dose. A similar impact on hepatic peroxidase activity has also been observed, indicating a partial detoxication of hydrogen peroxide by both catalase and peroxidase.     

HPLC-MS鉴定塔中栽培肉苁蓉药材的17个成分

目的:通过HPLC-MS对新疆塔中荒漠栽培肉苁蓉Cistanche deserticola药材60%甲醇提取物的色谱图进行鉴定。方法:采用Agilent ZORBAX Eclipse Plus C_(18)色谱柱(4.6 mm×250 mm,5μm),以乙腈-水(含0.1%的甲酸)为流动相进行梯度洗脱,流速1 mL·min~(-1),检测波长254 nm,柱温25℃,进样量10μL。结果:在相同色谱条件下,通过与已分离得到的对照品的保留时间、相对分子质量以及碎片离子进行比较,对新疆塔中荒漠栽培肉苁蓉药材的16个色谱峰中的17个成分进行了准确的鉴定,分别确定为松柏苷,去甲紫丁香苷,紫丁香苷,松果菊苷,肉苁蓉苷A,类叶升麻苷(管花苷A),肉苁蓉苷B,异类叶升麻苷,2'-乙酰基肉苁蓉苷A,肉苁蓉苷C,异肉苁蓉苷C,2'-乙酰基类叶升麻苷,管花苷B,epimeridinoside A,肉苁蓉苷K,肉苁蓉苷J。结论:该研究方法适用于肉苁蓉60%甲醇提取物色谱峰的鉴定,为全面分析该药材的化学成分提供了一定的科学数据。     

Eriosema laurentii De Wild (Leguminosae) methanol extract has estrogenic properties and prevents menopausal symptoms in ovariectomized Wistar rats

Ethnopharmacological relevance

Eriosema laurentii De Wild (Leguminosae) is a medicinal plant used in West and Central Africa for different diseases. In Cameroon, this plant is used as a treatment for infertility, and various gynecological and menopausal complaints. However, despite this use as a natural remedy, the biological activity of Eriosema laurentii has not been studied until now.

Aim of study

In order to determine the potential use of this plant in gynecological conditions/disorders, we evaluated the estrogenic properties of a methanol extract of its aerial parts and its ability to prevent different menopausal health problems induced by bilateral oophorectomy.

Material and methods

Two approaches were used. In vitro, recombinant yeast systems were applied, featuring either the respective human receptors (ERα, AR, and PR) or into chromosome III integrated human aryl hydrocarbon receptor (AhR) and the respective reporter plasmid. In vivo, the investigation was carried out using the 3 days uterotrophic assay and 9 weeks oral treatment in ovariectomized rats.

Results

The results showed that the methanol extract of the aerial parts of Eriosema laurentii transactivated the estrogen receptor-α and displayed AhR agonistic activity but was neither androgenic nor progesteronic. In rats, the extract did not induce endometrium proliferation either in the 3-day or the 9-week treatment regimens, but induced vaginal stratification and cornification, prevented loss of femur bone mass, increased high density lipoprotein cholesterol (HDL-C), and reduced total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), TC/HDL-C ratio, LDL-C/HDL-C ratio and the atherogenic index of plasma (AIP).

Conclusion

These results suggest that the methanol extract of the aerial parts of Eriosema laurentii does not seem to have an undesirable influence on the endometrium but might prevent vaginal dryness and bone mass loss and improve the lipid profile.     

异亚丙基莽草酸脂质体的包封率测定方法比较

目的:研究异亚丙基莽草酸脂质体含量和包封率的测定方法,建立一套准确度好、简便可行的质控方案。方法:采用Agilent Eclipse Plus C18色谱柱(4.6 mm×100 mm,3.5μm),流动相乙腈-0.05%磷酸溶液(10∶90),检测波长220 nm,流速1.0 mL·min-1,柱温30℃,进样量20μL。采用HPLC测定脂质体中异亚丙基莽草酸的含量;比较超滤法、凝胶色谱法和透析法用于包封率的测定。结果:异亚丙基莽草酸脂质体采用4倍量甲醇破乳并高速离心沉淀后,取上清液进行测定,药物专属性良好,线性范围1.004～150.6 mg·L-1(r=0.999 9),加样回收率(102.01±1.18)%,准确度和精密度良好,异亚丙基莽草酸对照品溶液于6 h内稳定;超滤法、葡聚糖凝胶法及透析法测得的包封率分别为(92.96±1.91)%,(91.23±2.23)%,(73.66±7.10)%。结论:所建立的HPLC稳定可靠、准确度良好,可用于异亚丙基莽草酸脂质体的质量控制和体外分析;超滤法测定包封率简便快捷、测定结果与凝胶色谱法相当,可作为本品包封率测定的常规方法;透析法由于测定条件的限制,其测定结果受脂质体溶液稳定性、药物在脂质体中存在状态的影响较大,可能会造成测定结果偏低。     

狗脊毛甲醇提取物UPLC/Q-TOF-MS分析

目的：探索狗脊毛化学成分组成及其外用止血的物质基础。方法：采用超声、索氏、回流3种方式对狗脊毛进行甲醇提取,通过UPLC/Q-TOF-MS对各提取物进行定性分析,流动相乙腈（A）-水（B）梯度洗脱（0~5 min,5%~55% A;5~7 min,55%~85% A;7~15 min,85%~100% A;15~20 min,100% A）,检测波长254 nm,m/z扫描范围100~1 000,脱溶剂气温度350 ℃,脱溶剂气体积流量9 L·min^-1,喷雾器压力2.4×10⁵Pa,毛细管电压4 000 V。结果：3种方式共检出化合物50个,给出了其中38个化合物的推荐分子式和名称。编号32~39共8个化合物为一系列三酰基甘油类同系物。结论：狗脊毛中化合物包括植物油类（三酰基甘油）、有机酸类、有机酸酯类、生物碱类、黄酮类、多酚类、糖苷类等,相对分子质量集中于200~800,三酰基甘油可能为主要药效成分。