Combined antihypertensive effect of luteolin and buddleoside enriched extracts in spontaneously hypertensive rats

Ethnopharmacological relevance

Flos Chrysanthemi is used in a variety of diseases in traditional Chinese medicine including hypertension, and the total flavonoids (rich in luteolin (LUT) and buddleoside (BUD)) of Flos Chrysanthemi is known to modulate vascular functions and reduce the blood pressure. However, the active flavonoids and their synergistic effects on anti-hypertension are still unclear. To investigate the combined anti-hypertension effects of LUT and BUD enriched extracts on spontaneously hypertensive rats (SHR), as well as the anti-hypertensive mechanism of LUT&BUD mixture.

Materials and methods

CODA Mouse & Rat Tail-Cuff Blood Pressure System was used to measure the systolic blood pressure (SBP) and diastolic blood pressure (DBP) of SHR after treated with extracts contains with LUT and/or BUD. The expressions of Ang II, PRA, ALD, ET, PGI₂ and TXB₂ were investigated by ELASA. Serum NO concentration was measured by the method of Nitric acid reductase.

Results

A single administration of LUT, BUD, or LUT:BUD=1:1 significantly reduced SBP by about 3.35 mmHg, 4.39 mmHg and 15.42 mmHg, respectively. Chronic administration of LBM (at 60 mg/kg; p.o. for 30 days) reduced both SBP and DBP by 4.04% and 5.24% of the vehicle group, respectively. Oral administration of LBM at 60 mg/kg inhibited the serum levels of ANG, ALD and ET, but increased serum NO concentration.

Conclusion

This study shows the synergistic anti-hypertension effects of LUT and BUD in SHR. The effects of LBM on blood pressure are associated with RAAS and endothelial system. Thus, our experiments suggest that the combination of luteolin and buddleoside from Flos Chrysanthemi are potentially useful for the therapeutic treatments for hypertension.     

Effect of Cydonia oblonga Mill. leaf extracts or captopril on blood pressure and related biomarkers in renal hypertensive rats

Ethnopharmacological relevance

Cydonia oblonga Mill. (COM) is used in traditional Uyghur medicine to treat or prevent cardiovascular disease. In a previous study COM leaf extracts were found to be active in renal hypertensive rats (RHR). The present study tests the dose-dependence of the effect of ethanol leaf extracts on hypertension and on biomarkers associated with blood pressure control, such as angiotensin-II (AII), plasma renin activity (PRA), apelin-12 (A), endothelin (ET) and nitric oxide (NO), compared to captopril.

Methods

Two-kidney one-clip (2K1C) Goldblatt model rats were divided randomly into six groups: sham, model, captopril 25 mg/kg, COM leaf extract 80, 160 and 320 mg/kg (n=10 each). Drugs were administered orally daily for eight weeks. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured before treatment and every 2 weeks. Blood and kidney samples were collected after the last treatment to measure AII, PRA, A, ET and NO.

Results

RHR had increased blood pressure, AII, A, PRA, ET and decreased NO. Treatment with captopril reduced blood pressure, AII, A, PRA, and ET, though not quite to normal values. COM leaf extracts significantly and dose-dependently reduced blood pressure, AII, A, RA and ET, whereas NO was increased. The highest dose of COM had the same effects as captopril.

Conclusion

The effects of COM extracts on blood pressure and biomarkers were dose-dependent and at the highest dose similar to those of captopril. This suggests an action of COM on the renin–angiotensin system, which could explain its antihypertensive effect.     

Antihypertensive activity of Rosa rugosa Thunb. flowers: Angiotensin I converting enzyme inhibitor

Ethnopharmacological relevance

Rosa rugosa Thunb.'s flowers have been used for medicinal and food purposes for hundreds years in China. They have been used in Traditional Chinese Medicine (TCM) to effectively help in expansion of blood vessels and improvement of microcirculation. Current high prevalence of hypertension, and the associated side effects of synthetic Angiotensin I converting enzyme inhibitors usually prescribed for this condition, led us to the investigation of possible inhibitory activity of the Rosa rugosa Thunb. flower extracts on Angiotensin I converting enzyme (ACE).

Materials and methods

Two different extraction preparation: (1) powdered materials were extracted with water (RW) and then with water (RWW), ethyl acetate (RWE) and 95% ethanol (RWE95); (2) powdered materials were extracted with 95% ethanol (RE95) and then with water (RE95W), ethyl acetate (RE95E) and 95% ethanol (RE95E95). The inhibition activity was determined using in vitro the inhibitory effect on Angiotensin I converting enzyme (ACE), and using the acute response and chronic response on blood pressure which measured in spontaneously hypertensive rats (SHRs).

Results

Both RE95E95 and RWW had highest ACE inhibitor activities. The higher inhibitor activity of RE95E95 was also evaluated in SHRs by oral administration for antihypertensive effect. In acute experiment, the decrease in systolic blood pressure (SBP) and the increase in heart rate (HR) was observed at 2 h after administration at high (40 g/kg) and low (20 g/kg) dose; such reductions in SBP were maintained for 12 h. Low dose had reduced SBP significantly more than high dose. In multiple oral administration chronic experiment, a SBP reduction of 17.5 mmHg was observed after 6d administration at low dose, and such reductions were maintained for the next 8 days.

Conclusions

The experimental results demonstrated the antihypertensive effect of Rosa rugosa Thunb. flowers, which was attributed to inhibition of Angiotensin I converting enzyme.     

The anti-Candida activity of Thymbra capitata essential oil: effect upon pre-formed biofilm

Ethopharmacological relevance

Thymbra capitata essential oil is traditionally considered to exhibit powerful antiseptic properties, thus being used to treat cutaneous infections. The aim of the present study was to evaluate the effect of Thymbra capitata essential oil upon pre-formed biofilm of different Candida strains while comparing it with the activity against planktonic cells.

Materials and methods

Fifteen Candida isolates were included, corresponding to clinical and collection type strains. Essential oil was obtained by hydrodistillation and its composition analysed by GC/MS. Activity upon planktonic cells was evaluated according to M27-A3 macromethod. Its effect upon 24 h preformed biofilm biomass was determined using the crystal violet procedure and the metabolic activity was studied applying the XTT/menadione technique.

Results

Biofilm biomass and metabolic activity of all tested species were reduced up to 50% at MIC values. The effect was more pronounced at double MIC values, achieving >80% reduction, except for Candida albicans that presented a more resistant profile (62%).

Conclusion

Thymbra capitata essential oil presented an important effect upon Candida biofilms. It is proposed as a valuable antifungal product to be used in an appropriate pharmaceutical formulation for the management of resistant mucocutaneous candidosis.     

Effect of Solanum torvum on blood pressure and metabolic alterations in fructose hypertensive rats

Ethnopharmacological relevance

Solanum torvum (Solanaceae) is a plant used in Cameroon ethnomedicine for the treatment of hypertension.

Aim of the study

The present study was aimed to determine the effect of ethanolic extract of Solanum torvum (100 and 300 mg/kg; p.o. for 6 weeks) on systolic blood pressure (SBP), vascular reactivity, serum glucose, triglycerides, cholesterol, insulin and uric acid in fructose-induced hypertension.

Materials and methods

The effect of ethanolic extract of Solanum torvum (100 and 300 mg/kg; p.o. for 6 weeks) on fructose (10%) induced rise in blood pressure was tested by invasive and non-invasive measurements and the biochemical parameters were studied by using standard kits.

Results

Ethanolic extract of Solanum torvum reduced systolic blood pressure, vascular reactivity changes to catecholamines and reversed the metabolic alterations induced by fructose. The cumulative concentration response curve (CCRC) of Angiotensin II (Ang II) using isolated strip of ascending colon was shifted towards right in rats treated with ethanolic extract of Solanum torvum.

Conclusions

In conclusion, ethanolic extract of Solanum torvum could prevent the development of high blood pressure induced by a diet rich in fructose probably by reversing the metabolic alterations induced by fructose.     

Systematic review and meta analysis of randomized controlled trials on Tianmagouteng decoction in treatment of primary hypertension with liver Yang hyperactivity syndrome

Objective

To assess the efficacy of Tianmagouteng decoction in the treatment of primary hypertension with liver yang hyperactivity syndrome.

Methods

The databases of MEDLINE (1950-2012), EMbase (1980-2012), China biology medicine (CBM) (1994-2012), China national knowledge infrastructure (CNKI) (1989-2012), Weipu (VIP) (1995-2012) and Wanfang (1989-2012) were searched and we performed manual searches for conference proceedings to select randomized controlled trials (RCTs) on Tianmagouteng decoction for the treatment of primary hypertension with liver Yang hyperactivity syndrome. Studies were enrolled according to the study-selecting criteria. The methodological quality was evaluated, data were extracted and meta-analyses were conducted with RevMan 4.2 software.

Results

Nine RCTs were selected involving 784 patients with no significant difference in decrease in systolic blood pressure (SBP) [OR=1.02, 95% CI (-0.24, 2.29), P=0.10] and diastolic blood pressure (DBP) [OR=0.56, 95% CI (-0.10,1.23), P=0.11] between the Tianmagouteng group and the control group. While there was a significantly larger increase in serum superoxide dismutase (SOD) [OR= 6.26, 95% CI (1.27,11.66), P=0. 01] in the Tianmagouteng group than that in the control group

Conclusion

Tianmagouteng decoction can decrease both systolic and diastolic blood pressure and greatly increase serum SOD. Due to poor quality of included studies, the efficacy needs to be further assessed.     

Anticonvulsant activity of the essential oil and methanolic extract of Bunium persicum (Boiss). B. Fedtsch

Ethnopharmacological relevance

Bunium persicum is an endemic plant to Iran which its seeds have a long history of medicinal uses.

Aim of the study

This work aimed to study the anticonvulsant effect of the essential oil and methanolic extract of the plant.

Materials and methods

The essential oil and methanolic extract of the plant were studied against pentylenetetrazole (PTZ) and maximal electroshock (MES) induced convulsions in mice in different doses. The neurotoxicity of the essential oil and methanolic extract was investigated using rotarod method.

Results

The essential oil and methanolic extract prolonged the onset of clonic and tonic seizures in PTZ. The tonic seizures were prevented by essential oil in both methods at dose of 1 mL/kg and higher doses. The methanolic extract inhibited PTZ-convulsions at dose 3 g/kg and was ineffective against MES induced convulsion.

Conclusions

The essential oil of the plant might be useful to control absence and grand mal seizures at dose 1 mL/kg. This activity might be due to its content of monoterpenes.     

Cytotoxicity and antibacterial activity of Lindera strychnifolia essential oils and extracts

Aim of the study

Lindera strychnifolia (LS) is widely used in traditional Chinese medicine. In the present study, we investigated cytotoxicity and antibacterial activity of essential oils and various fractions of ethanol extract of LS to explore the active components of LS and their pharmacological effects.

Materials and methods

The in vitro cytotoxicities of essential oils and various solvent fractions of LS on three human cancer cell lines (A549, HeLa and Hep G2) and a non-cancerous cell line (HUVEC) were examined using a modified MTT assay. And by using agar disc diffusion and broth microdilution methods, the antibacterial activity of these samples was evaluated against 10 bacteria including 5 clinically isolated strains. The compositions of the essential oils from the leaves and roots of LS were also analyzed by GC and GC–MS.

Results

The leaf oil showed the strongest cytotoxicity on the cancer cell lines tested with the IC₅₀ values ranged from 22 to 24 μg/ml after 24 h of treatment. The most sensitive microbial strain to all the samples was Staphylococcus aureus ATCC 25923.

Conclusions

Our results showed that the essential oils of LS exhibited greater cytotoxicity and antibacterial activity than the solvent fractions of ethanol extract of LS.     

Effect of American ginseng (Panax quinquefolius L.) on arterial stiffness in subjects with type-2 diabetes and concomitant hypertension

Ethnopharmacological relevance

Substantial pre-clinical and some clinical data are available showing that Asian ginseng (Panax ginseng C.A. Meyer) varieties or its particular ginsenosides exert a vasodilatating effect, thus may modulate vascular function. However, the clinical evidence for American ginseng (Panax quinquefolius L.) is scarce. Therefore, this study evaluates the effect of American ginseng (AG) on arterial stiffness, as measured by augmentation index (AI), and blood pressure (BP), in type 2 diabetes patients with concomitant hypertension.

Materials and methods

Using a double-blind, placebo-controlled, parallel design, each participant was randomized to either the selected AG extract or placebo at daily dose of 3 g for 12 weeks as an adjunct to their usual antihypertensive and anti-diabetic therapy (diet and/or medications). AI and BP were measured by applanation tonometry at baseline and after 12 weeks of treatment.

Results

A total of 64 individuals with well-controlled essential hypertension and type 2 diabetes (gender: 22 M:42 F, age:63±9.3 years, BP: 145±10.8/84±8.0 mmHg, HbA1c: 7.0±1.3%, fasting blood glucose (FBG): 8.1±2.3 mmol/L) completed the study. Compared to placebo, 3 g of AG significantly lowered radial AI by 5.3% (P=0.041) and systolic BP by 11.7% (P<0.001) at 12 weeks. No effect was observed with diastolic BP.

Conclusions

Addition of AG extract to conventional therapy in diabetes with concomitant hypertension improved arterial stiffness and attenuated systolic BP, thus warrants further investigation on long-term endothelial parameters before recommended as an adjunct treatment.     

Chemical constituents and antibacterial property of the essential oil of the roots of Cyathocline purpurea

Ethnopharmacological relevance

Cyathocline purpurea (D. Don.) O. Ktze. (Asteraceae) is a rare existence Indian medicinal plant and traditionally has antimicrobial property.

Aim of the study

The aim of the present study was to identify chemical composition of the essential oil from the roots of Cyathocline purpurea and to screened in vitro antibacterial activity against eight human pathogenic bacteria.

Materials and methods

The essential oil of roots was analyzed by using GC–FID and GC–MS. The antibacterial activity of oil was tested against four Gram-positive and four Gram-negative bacteria and antibacterial activity was determined by the tube dilution method.

Results

The main constituents of the oil were thymohydroquinone dimethyl ether (57.4%) and β-selinene (14.0%), among twenty five identified compounds, which represented 90.1% of the total oil. The oil was found active against Gram-positive bacteria with minimal bactericidal concentration (MBC) values in the range of 0.26–0.57 mg/mL.

Conclusions

This is the first report on the chemical composition and antibacterial activity of the essential oil of roots of Cyathocline purpurea. The observation of MBC assay suggested that the Gram positive microorganisms were susceptible to essential oil, while oil was found to be resistant against Gram-negative bacteria, and the oil has bactericidal property.