miRNA-150-5p associate with antihypertensive effect of epigallocatechin-3-gallate revealed by aorta miRNome analysis of spontaneously hypertensive rat.

AIMS: The antihypertensive mechanism (s) of the epigallocatechin-3-gallate (EGCG), a major effective component in green tea, might associate with microRNAs (miRNAs). Here, we aimed to investigate which microRNA in aorta of spontaneously hypertensive rats (SHRs) were modulated by administration of EGCG and its mechanism. MAIN METHODS: The pharmacokinetic behaviors of EGCG and epigallocatechin (EGC) in Sprague-Dawley rats were analyzed by HPLC and DRUG AND STATISTICS software. Blood pressure of SHRs was monitored by the tail-cuff method, the miRNomes of aorta from SHRs was analyzed with deep sequencing, and expression of hypertension-associated miRNAs with significant change and their host genes and target genes were validated by real-time PCR and Western blot. KEY FINDINGS: The plasma deposition of EGCG and EGC best fitted a mono-compartmental model with maximum plasma concentration post-dose (Cmax, 6.65 vs 4.45 µg/ml) and the corresponding time (Tmax, 15 vs 10 min). Systolic blood pressure (SBP) of SHRs decreased to the lowest point by 34.04 mmHg and recovered by 23.39 mmHg after 15 and 30 min of administration at dose of 300 mg/kg BW EGCG, respectively, and it decreased again at 60 min and recovered at time 2 h. Total 35 upregulated and 18 downregulated miRNAs were identified compared to the control group (p < .01) after EGCG administration. Expression of hypertension-associated miRNA-126a-3p and miRNA-150-5p were further validated. In turn, their host gene and target genes were up-regulated and down-regulated, respectively. SIGNIFICANCE: Our results indicated that miRNA-150-5p might be involved in the antihypertensive effect of EGCG through SP1/AT1R pathway.

[Effects of processing Phellodendron amurense with salt on anti-gout].

OBJECTIVE: To investigate the effects of processing Phellodendron anurene with salt on anti-gout. METHOD: The mouse serum uric acid level and liver xanthine oxidase activity were used to evaluate anti-gout effects of raw and processing P. amurense with salt. RESULT: Both raw and processing P. amurense with salt reduced serum uric acid levels in the in hyperuricemic mice, and inhibited activities of liver xanthine oxidase at the low and high doses respectively, thus exhibiting anti-gout effects. Moreover, they showed the tendency to decrease the uric acid levels in the normal animal only at the high dose. The latter was a little weaker than the former. CONCLUSION: Processing with salt might not significantly change anti-gout effect of P. amurense.

Aesculin possesses potent hypouricemic action in rodents but is devoid of xanthine oxidase/dehydrogenase inhibitory activity.

The natural product aesculin was demonstrated to possess potent hypouricemic effects in in vivo models of hyperuricemia in both mice and rats pretreated with oxonate. Aesculin, when administered intraperitoneally to the oxonate-induced hyperuricemic rodents, was able to elicit dose-dependent hypouricemic effects. At doses of 150 mg/kg of aesculin or above, the serum urate levels of the oxonate-pretreated mice were not different from normal mice. Such an effect in mice was observed as quick as 1.5 h after aesculin administration and was persistent for at least 5 h after aesculin administration. In rats, similar hypouricemic effects of intraperitoneally administered aesculin could also be demonstrated at doses of 100 mg/kg of aesculin or above, the serum urate levels of the oxonate-pretreated rats were not different from normal rats. Again, the effect persisted for at least 5 h after aesculin administration. In both rodents, however, oral administration at the same doses did not produce any observable hypouricemic effects. In addition, aesculin, when tested in vitro on rat and mouse liver homogenates, did not elicit any measurable inhibitory actions on the xanthine oxidase/xanthine dehydrogenase activities.