Protective effect of quercetin, a polyphenolic compound, on mouse corpus cavernosum

Abstract

Flavonoids are plant-based phenolic compounds, and quercetin is the most abundant dietary member of this family. One of the most important characteristics of quercetin is its antioxidant property. The aim of this study was to investigate antioxidant effects of quercetin on corpora cavernosa of mice. Corpora cavernosa were isolated in organ baths, precontracted with phenylephrine (0.5 microm) and relaxant responses were mediated by acetylcholine (0.1-1 microm), electrical field stimulation (EFS, 1-16 Hz, 0.5 ms, 30 V) or acidified sodium nitrite (a NaNO(2), 0.5 mm). Superoxide anion generators; pyrogallol (50 microm), hydroquinone (100 microm), LY 83583 (6-Anilinoquinolin-5,8-quinone, 10 microm) and superoxide dismutase (SOD) inhibitor; diethyldithiocarbamic acid (DETCA, 8 mm) were used in order to expose corpus cavernosa to oxidant stress. Acetylcholine (0.1-1 microm) induced relaxant responses were significantly inhibited in LY 83583 (10 microm) and DETCA + LY 83583 applicated trials. EFS-induced relaxant responses were significantly inhibited in DETCA (8 mm) and DETCA + LY 83583 administrated trials. On the other hand, acidified sodium nitrite-induced responses were inhibited by all of the superoxide anion generators tested. Quercetin (10 microm) failed to improve the inhibitions on endothelium and electrically stimulated responses. Acidified sodium nitrite (0.5 mm) mediated relaxant responses were significantly restored by quercetin except the groups in which LY 83583 were used. The data suggest that quercetin acts as a protective agent in mouse corpus cavernosum, increasing the bioavailability of exogenous nitric oxide by protecting it from superoxide anion (O(2)(-)).

Relaxant and Antioxidant Capacity of the Red Wine Polyphenols, Resveratrol and Quercetin, on Isolated Mice Corpora Cavernosa

“…This finding is in line with what was observed by Ertug et al. [25] who found that quercetin restored exogenous NO responses when mice CC were exposed to free radicals. This could imply that a certain amount of oxidative stress is required in order for quercetin or resveratrol to exert their beneficial effect.…”

“…In our study, neither resveratrol nor quercetin enhanced endogenously (Ach), exogenously (SNP), or neuronal (EFS) NO-mediated relaxation responses of CC. However, when oxidative stress was enhanced [25] who found that quercetin restored exogenous NO responses when mice CC were exposed to free radicals. This could imply that a certain amount of oxidative stress is required in order for quercetin or resveratrol to exert their beneficial effect.…”

Oximes Induce Erection and Are Resistant to Oxidative Stress

“…Furthermore, experiments on human CC and penile resistance arteries showed that antioxidant therapy ameliorates impaired NO‐mediated relaxations (both ACh and EFS) in diabetic patients with ED [26]. Oxidative stress alters NO‐mediated relaxations in mice CC, as the combination of the superoxide generator LY 83583 and the superoxide dismutase inhibitor DETCA inhibited corporal relaxations induced by EFS, ACh, and acidified sodium nitrite [14]. In our model of oxidative stress, we increased superoxide concentrations using the superoxide generator (free radical scavenger) hydroquinone [27,28] in combination with DETCA, an irreversible inhibitor of the Cu 2+ /Zn 2+ ‐containing superoxide dismutase [29].…”

“…Therefore, oxidative stress associated with hypertension [7], diabetes [8,9], aging [10,11], hypercholesterolemia [12], and radiation damage [13], can lead to ED. It was reported that oxidative stress impairs NO‐mediated relaxations of mice CC [14]. Hence, we were interested if oxidative stress also has an influence on the FAL‐/FAM‐induced corporal relaxations, as an impairment would limit their therapeutic relevance.…”

Oxidative Stress Damages the Endothelium

“…11 One could use lemon juice to prevent browning. The title of a report in the journal Fundamental & Clinical Pharmacology, "Protective effect of quercetin, a polyphenolic compound, on mouse corpus cavernosum," just about says it all.…”