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

Ethnopharmacological relevanceFlos 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 methodsCODA 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.ResultsA 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.ConclusionThis 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.

The antihypertensive effects of BUD, LUT and LBMs in SHRs. (A) The SBP and DBP in SHRs after single oral treatment with BUD (25 mg/kg/day), LUT (25 mg/kg/day) or LBM (25 mg/kg/day or 50 mg/kg/day). ⁎⁎P<0.01 vs. vehicle control, ΔP<0.05, #P<0.05, ##P<0.01 vs. BUD or LUT group. (B) The SBP and DBP of SHRs after single oral treatment with different ratio of LBMs. B+L=25+25 mg/kg; B+L=12.5+12.5 mg/kg; B+L=12.5+25 mg/kg; B+L=25+12.5 mg/kg. Blood pressure was measured after 2 h administration, and expressed as % of control (⁎⁎P<0.01 vs. vehicle control, ΔP<0.05, #P<0.05, ##P<0.01 vs. other groups.). Figure optionsDownload high-quality image (210 K)Download as PowerPoint slide