[Study on difference of flavonoids content in stems and leaves of Mentha Haplocalycis Herba in different harvest periods].

The dynamic changes of active components in stems and leaves of Mentha Haplocalycis Herba(mint) at different harvest periods were investigated, and the optimum harvest time of mint was explored. In this study, hesperidin, diosmin, didymin and buddleoside were selected as flavonoids index components of mint, and the QAMS method was established to measure the contents of these flavonoids in mint. The contents of 4 flavonoid glycosides in the mint stems and leaves from three habitats harvested in different time were studied and evaluated comprehensively using statistical analysis and principal component analysis (PCA). The results showed that the contents of 4 components in the leaves are higher than that in the stems despite of habitats and harvest time, and they all exhibited dynamic changes along with the harvest periods within the same habitat. Three harvest periods in mid April, mid September and late October scored higher in comprehensive evaluation in Jiangsu region, the genuine producing area of Mentha Haplocalycis Herba. Combined with the yield and contents of active compounds, the optimum harvest time of mint in Jiangsu region was mid September and late October, which is basically consistent with the traditional harvesting periods.

[Relaxation effect of buddleoside combined with luteolin on isolated vessels in vivo and its mechanism].

To study the relaxation effect of buddleoside combined with luteolin on aortic rings in SD rats and its mechanism. The effect of buddleoside alone(7.5×10⁻6g•mL⁻¹), luteolin alone(7.5×10⁻6g•mL⁻¹) and the combination of buddleoside and luteolin(1∶4) on norepinephrine-induced contractility of complete, endothelium-denuded, and L-NAME and indomethacin-pretreated thoracic aorta in SD rats were observed in the in vitro ring tension test. Western blot was used to detect p-Akt and p-eNOS protein expressions in the thoracic aorta. The experimental results showed that buddleoside combined with luteolin could significantly increase the relaxation rate of blood vessels and endothelium and L-NAME-pretreated vascular rings compared with the two single administrations. And buddleoside combined with luteolin could also significantly increase p-Akt and p-eNOS protein expressions.The results suggested that the combination of buddleoside and luteolin could effectively relax the blood vessel, and the mechanism may be to increase the synthesis and release of NO and reach the role of relaxing blood vessel by activating PI3K/Akt/NO signaling pathway and enhancing the activity of eNOS.

Buddleoside-Rich Chrysanthemum indicum L. Extract has a Beneficial Effect on Metabolic Hypertensive Rats by Inhibiting the Enteric-Origin LPS/TLR4 Pathway.

As the number of patients with metabolic hypertension (MH) is increasing, there is an essential require for global measures to prevent and treat MH. Flavonoids such as buddleoside (BUD) from Chrysanthemum indicum L. are the main pharmacological components of cardiovascular activities. Previous studies have suggested that the buddleoside-rich Chrysanthemum indicum L. extract (BUDE) can reduce blood pressure in spontaneously hypertensive rats (SHR). However, its effect on MH and how it works remains to be researched. In this study, it was observed that BUDE could lower blood pressure, improve dyslipidemia, and decrease the level of plasma LPS in MH rats. Moreover, BUDE improved intestinal flora and increased the expression of occludin and claudin-1 in the colon, and improved the pathological injury of the colon. Western bolt and qRT-PCR experiments showed that BUDE could down-regulate TLR4 and MyD88 protein and mRNA expression and inhibit phosphorylation of IKKß, IκBα and NF-κB p65 in vessels of MH rats. These results showed that BUDE could regulate intestinal flora, improve intestinal barrier function, reduce the production and penetration of LPS, thereby inhibiting the vascular TLR4/MyD88 pathway, improving vascular endothelial function, and ultimately lowering blood pressure in MH rats. This study provides a new mechanism of BUDE against MH by inhibiting the enteric-origin LPS/TLR4 pathway.

A comparative study of Mentha arvensis L. and Mentha haplocalyx Briq. by HPLC.

We have developed a new method to simultaneously determine five marker compounds in Menthae Herba via HPLC/PDA - including hesperidin (1), rosmarinic acid (2), diosmin (3), didymin (4) and buddleoside (5). The newly developed method was successfully used to analyse for two species (Mentha arvensis L. and Mentha haplocalyx Briq.) of Menthae Herba, and the satisfactory results were obtained from the validation of developed method. The pattern analysis could greatly discriminate between M. arvensis L. and M. haplocalyx Briq. In conclusion, the proposed HPLC/PDA method is suitable for quality evaluation of Menthae Herba.

Biotransformation and metabolic profile of buddleoside with human intestinal microflora by ultrahigh-performance liquid chromatography coupled to hybrid linear ion trap/orbitrap mass spectrometer.

Buddleoside (also known as linarin) as the major flavonoid in Chrysanthemum morifolium Ramat., has been reported to possess a wide range of pharmacological activities. The human intestinal microbiota might have an important impact on drug metabolism and ultimately on the drug oral bioavailability. However, the interaction of the buddleoside with human intestinal bacteria remains unknown. In this study, the conversion of buddleoside by different bacteria from human feces was firstly investigated. A reliable, sensitive and rapid analytical method, ultra performance liquid chromatography was established and successfully applied to investigate the metabolites and metabolic profile of buddleoside by human intestinal bacteria. Among the isolated bacteria, four strains including Escherichia sp. 4, Escherichia sp. 34, Enterococcus sp. 45 and Bacillus sp. 46 showed more powerful conversion capability. Based on the accurate mass data and the characteristic MS(n) product ions, the parent and six metabolites were detected and tentatively identified compared with blank samples. The metabolites were produced by four main metabolic pathways including deglycosylation, acetylation, methylation and hydroxylation. Buddleoside could be firstly converted to its aglycon acacetin (M2) by the majority of the isolated intestinal bacteria. Subsequently, M2 was further metabolize to its methylated (M3), acetylated (M4), hydroxylated (M5) and hydrogenated product (M6). However, acacetin-7-glucosid (M1) was obtained only from the minor bacterial samples like Bacillus sp. 46. To further explain the metabolism of buddleoside, the ß-d-glucosidase and α-l-rhamnosidase activities of four strains were analyzed. Bacillus sp. 46 could only produce α-l-rhamnosidase, while the other three strains showed two kinds of enzyme activities. Furthermore, the activities of α-l-rhamnosidase and ß-d-glucosidase reached the highest level at 12-18h and 10-12h, respectively. The metabolic routes and metabolites of buddleoside produced by human intestinal microflora were firstly reported in this paper. The results will be very helpful for the further investigation of the pharmacokinetic research of buddleoside and to unravel how it works in vivo.

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.