Haemodynamic effects of the flavonoid quercetin in rats revisited

Abstract

Background and Purpose The flavonoid quercetin increased the in vitro potency of the α1‐antagonist tamsulosin to reduce phenylephrine‐dependent arterial contractions by 10‐fold. To examine if this supplement–drug interaction luxates hypotensive and orthostatic events in vivo, several set of studies were conducted in spontaneously hypertensive (SHR) and normotensive (Wistar Kyoto [WKY]) rats. Experimental Approach First, in rats pretreated with quercetin or its vehicle, responses to phenylephrine and tamsulosin were examined. Second, tamsulosin‐induced changes in renal, mesenteric, hindquarter and carotid conductance were compared in quercetin‐ and vehicle‐treated rats instrumented with Doppler flow probes. Animals were also placed on a tilt table to record regional haemodynamic changes to orthostatic challenges. Third, adult SHR were instrumented with telemeters to measure 24‐hr patterns of BP. Recordings were made before and during a 5‐week oral treatment of quercetin. Finally, pre‐hypertensive SHR were treated with quercetin from 4 to 8 weeks of age and arterial pressure was measured at 8 and 12 weeks. Key Results Pretreatment with quercetin did not influence the responses to phenylephrine and tamsulosin, in neither WKY nor SHR. While tamsulosin treatment and tilting lowered BP and increased conductance in all vascular beds, effect size was not influenced by pretreatment with quercetin. Prolonged treatment with quercetin, in either prehypertensive SHR or adult SHR with established hypertension did not lower BP. Conclusions and Implications Cumulatively, these data demonstrate that quercetin does not amplify haemodynamic effects of tamsulosin or tilting in vivo in rats and has no effect on BP development in SHR.

Quercetin inhibited the proliferation and invasion of hepatoblastoma cells through facilitating SIRT6-medicated FZD4 silence

“…5 Quercetin has many pharmacological effects, including anti-inflammatory, antioxidant, anti-atherogenic as well as antitumor activities. 6,7 Indeed, quercetin is a unique compound due to its potential to combat cancer-related diseases in a multi-targeted manner. Quercetin was reported to modulate various pathways to cause cell cycle arrest and promote apoptosis.…”

Morphological changes in tissues of organs in rats with arterial hypertension (SHR) with treatment of hypotensive medicines (with ramipril and candesartan) in combination with corvitin

“…It is known from the literature that SHR rats have increased renal production of angiotensinogen, which leads to increased levels of ABP, hypertension and kidney damage [13,16]. The combined effect of corvitin and ramipril on the kidneys reduced the degree of atrophy of the renal glomeruli with no pathological process when combining candesartan and corvitin with long-term treatment [18,19]. Ramipril contributes to the normaliza-tion of systemic blood pressure and increased blood flow to the kidneys, and in combination with corvitin enhances positive dynamics [20].…”

Quercetin treatment reduces the severity of renal dysplasia in a beta-catenin dependent manner

“…Quercetin is a flavonoid found in various fruits and vegetables and is one of the most abundant natural plant polyphenols found in the human diet [21]. Quercetin has been widely researched for its diverse therapeutic properties, such as anti-inflammatory [22][23][24], antioxidant [24,25], anti-microbial [26], anti-hypotensive and anti-atherogenic [27], as well as protecting against metabolic and agingrelated diseases [24,28] and protecting cells against high glucose induced damage [29]. Further, studies have also demonstrated that quercetin inhibits nuclear beta-catenin accumulation and decreases the transcriptional activity of beta-catenin target genes in colon, pancreatic, and breast cancer cells [21,30,31].…”