Free radical-scavenging activity of Korean red ginseng for erectile dysfunction in non-insulin-dependent diabetes mellitus rats.
OBJECTIVE
To investigate the antioxidant activity of Korean red ginseng (KRG) and its effect on erectile function in non-insulin-dependent diabetes mellitus (NIDDM) rats. Oxidative stress is an important factor in vascular complications of diabetes.


METHODS
A total of 84 male Sprague-Dawley rats were included in this study. NIDDM was induced by an intraperitoneal injection of 90 mg/kg of streptozotocin on day 2 after birth. According to the diabetic period, they were classified as either short-term (22 weeks, n = 32) or long-term (38 weeks, n = 32) diabetics. Of those, 20 (10 short-term and 10 long-term) were fed 30 mg/kg of KRG three times weekly for 1 month. The remaining diabetic rats (22 short-term and 22 long-term) and their age-matched controls (n = 10 each for each group) were fed a normal diet. Erectile function was measured after electrostimulation of the cavernous nerve. The total cavernous malondialdehyde and glutathione levels were measured using a spectrophotometric assay.


RESULTS
The intracavernous pressure after nerve stimulation and cavernous glutathione level were significantly lower in the long-term than the short-term diabetics with a normal diet and were markedly decreased compared with their age-matched controls (P <0.01 and P <0.05, respectively). The malondialdehyde content was markedly increased in the short-term diabetics compared with the controls (P <0.05). In contrast, erectile function was not impaired in the diabetic group treated with KRG. Furthermore, both glutathione and malondialdehyde levels in those treated with KRG were comparable to their age-matched controls.


CONCLUSIONS
Oxidative stress to cavernous tissue may be a contributory factor in erectile dysfunction in diabetics. KRG may preserve potency in the NIDDM rats through its antioxidant activity.
Ryu
Ji-Kan
JK
Department of Urology, Inha University School of Medicine, Incheon, Republic of Korea.
Lee
Tack
T
Kim
Dae-Joong
DJ
Park
In-Sun
IS
Yoon
Sang-Min
SM
Lee
Hong-Sik
HS
Song
Sun U
SU
Suh
Jun-Kyu
JK
D000818:Animals; D000975:Antioxidants / Q000627:therapeutic use*; D048909:Diabetes Complications / Q000188:drug therapy*; D003921:Diabetes Mellitus, Experimental; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000188:drug therapy*; D007172:Erectile Dysfunction / Q000188:drug therapy* / Q000209:etiology*; D008297:Male; D005894:Panax; D008517:Phytotherapy; D028321:Plant Preparations / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley
D000975:Antioxidants; D028321:Plant Preparations