Study on antipyretic effect of rhubarb on rats and its antipyretic ingredients / 中国中药杂志

A combination of LC-MS technology and activity evaluation was used to identify the antipyretic ingredients in rhubarb. The rat model of fever was established with dried yeast and then was administered ethanol extract and different polar fractions of rhubarb. Next, the anal temperature of these rats was measured and recorded at 0.5, 1, 2, 3, 4 and 5 h after administration, and the inhibition rate of each part on the rise of body temperature was calculated. The inhibition rate is higher and the antipyretic effect is better. The chemical composition of the effective fraction was analyzed with UPLC-ESI-Orbitrap-MS/MS technology. Compared with the model group, the increase of body temperature of ethanol extract group all reduced at each measurement time especially after 3 h, and the inhibition rate were 38.7%(P<0.05), 78.2%(P<0.01) and 72.4%(P<0.01) at 3 h, 4 h, and 5 h after administration, respectively. Both n-butanol and water fraction showed some antipyretic activity in the early stage, with the inhibition rate of 28.1%(P<0.01) and 24.9%(P<0.05) at 1 h after administration, respectively, while other fractions were not active. Thirty-three and twelve compounds were identified from n-butanol and water fraction by LC-MS/MS analysis, respectively, including ten tannins, fifteen anthraquinone glycosides, four anthrone glycosides, one phenolic glycoside, one naphthaline derivative, one anthraquinone and one sucrose. These results revealed that rhubarb had antipyretic activity on rats, and tannin and anthraquinone glycosides were the main active ingredients inside.

Effect of rhubarb on extravascular lung water in patients with acute respiratory distress syndrome

Summary Objective: The aim of this study was to evaluate the effect of rhubarb on extravascular lung water (EVLW) in patients with acute respiratory distress syndrome (ARDS). Method: A total of 80 patients with ARDS were randomly divided into a treatment group (40 cases) and control group (40 cases). Patients in the treatment group received rhubarb (30.0 g/d) and patients in the control group received conventional therapy for seven consecutive days. Extravascular lung water index (EVLWI) and pulmonary vascular permeability index (PVPI) were determined using pulse contour cardiac output (PiCCO) technology, and the oxygenation index was measured by blood gas analysis at baseline and on days 3, 5 and 7 after treatment. Results: The oxygenation index was higher and the levels of EVLWI and PVPI were lower after treatment in the two groups; however, these indexes showed significant differences on the 5th and 7th days after rhubarb treatment compared with the results in the control group (p<0.05). Conclusion: Rhubarb can decrease EVLWI and PVPI, and improve oxygenation in patients with ARDS.

Estimation of antioxidant, antimicrobial activity and brine shrimp toxicity of plants collected from Oymyakon region of the Republic of Sakha (Yakutia), Russia

BACKGROUND: Several plants are reported to be produced various biological active compounds. Lichens from the extreme environments such as high altitude, high UV, drought and cold are believed to be synthesized unique types of secondary metabolites than the other one. Several human pathogenic bacteria and fungi have been muted into drug resistant strains. Various synthetic antioxidant compounds have posed carcinogenic effects. This phenomenon needs further research for new effective drugs of natural origin. This manuscript aimed to screen new source of biological active compounds from plants of subarctic origin. RESULTS: A total of 114 plant species, including 80 species of higher plants, 19 species of lichens and 15 species of mosses, were collected from Oymyakon region of the Republic of Sakha (Yakutia), Russia (63˚20′N, 141˚42′E - 63˚15′N, 142˚27′E). Antimicrobial, DPPH free radical scavenging and brine shrimp (Artemia salina) toxicity of all crude extract were evaluated. The obtained result was analyzed and compared with commercial standards. A total of 28 species of higher plants showed very strong antioxidant activity (DPPH IC50, 0.45-5.0 µg/mL), 13 species showed strong activity (DPPH IC50, 5-10 µg/mL), 22 species showed moderate antioxidant activity (DPPH IC50,10-20 µg/mL) and 17 species showed weak antioxidant activity (DPPH IC50 more than 20 µg/mL). Similarly, 3 species of lichen showed strong antioxidant activity, one species showed moderate and 15 species showed weak DPPH reducing activity. In addition, 4 species of mosses showed moderate antioxidant activity and 11 species showed weak antioxidant activity. Similarly, extracts of 51 species of higher plants showed antimicrobial (AM) activity against Staphylococcus aureus and 2 species showed AM activity against Candida albicans. Similarly, 11 species of lichen showed AM activity against S. aureus and 3 species showed AM activity against Escherichia coli. One species of moss showed AM activity against S. aureus. And finally, one species of higher plant Rheum compactum and one species of lichen Flavocetraria cucullata showed the toxicity against Brine shrimp larvae in 100 µg/mL of concentration. CONCLUSION: The experimental results showed that subarctic plant species could be potential sources of various biologically active natural compounds.

Piceatannol-3'-O-beta-D-glucopyranoside as an active component of rhubarb activates endothelial nitric oxide synthase through inhibition of arginase activity

Arginase competitively inhibits nitric oxide synthase (NOS) via use of the common substrate L-arginine. Arginase II has recently reported as a novel therapeutic target for the treatment of cardiovascular diseases such as atherosclerosis. Here, we demonstrate that piceatannol-3'-O-beta-D-glucopyranoside (PG), a potent component of stilbenes, inhibits the activity of arginase I and II prepared from mouse liver and kidney lysates, respectively, in a dose-dependent manner. In human umbilical vein endothelial cells, incubation of PG markedly blocked arginase activity and increased NOx production, as measured by Griess assay. The PG effect was associated with increase of eNOS dimer ratio, although the protein levels of arginase II or eNOS were not changed. Furthermore, isolated mice aortic rings treated with PG showed inhibited arginase activity that resulted in increased nitric oxide (NO) production upto 78%, as measured using 4-amino-5-methylamino-2',7'-difluorescein (DAF-FM) and a decreased superoxide anions up to 63%, as measured using dihydroethidine (DHE) in the intact endothelium. PG showed IC50 value of 11.22 microM and 11.06 microM against arginase I and II, respectively. PG as an arginase inhibitor, therefore, represents a novel molecule for the therapy of cardiovascular diseases derived from endothelial dysfunction and may be used for the design of pharmaceutical compounds.