Alkaloid extracts from Bitter leaf (Vernonia amygdalina) and Black nightshade (Solanum nigrum) inhibit phosphodiesterase-5, arginase activities and oxidative stress in rats penile tissue.

The erectogenic potential of alkaloids extracted from Bitter leaf (Vernonia amygdalina) and Black nightshade (Solanum nigrum) was investigated in this study. Fresh leaves obtained from Bitter leaf and Black night shade were air-dried, pulverized, and extracted for alkaloids. The inhibitory potential of the alkaloid extracts on arginase and phosphodiesterase-5 (PDE-5) activities in rats penile tissue was determined in vitro. The antioxidant properties were also evaluated and the constituent alkaloids quantified using GC-MS. The alkaloid extracts inhibited arginase (0-30.51 µg/ml) and PDE-5 (0-133.69 µg/ml) activities in a concentration-dependent pattern. Similarly, the alkaloid extracts inhibited Fe2+ -induced lipid peroxidation in rats penile tissues, scavenged DPPH, OH, and NO radicals as a function of concentration. GC-MS characterization revealed over 20 alkaloid compounds. The inhibition of PDE-5-, arginase-, pro-oxidant-induced lipid peroxidative-, and free radicals-scavenging activities by the alkaloids is suggestive of putative mechanisms underlying their therapeutic use for managing erectile dysfunction in folklore medicine. PRACTICAL APPLICATIONS: Alkaloids extracted from Black nightshade (Solanum nigrum) and Bitter leaf (Vernonia amygdalina) were characterized and investigated by standard procedures for inhibitory action against key erectile dysfunction-linked enzymes and antioxidant activity. The alkaloids inhibited erectile dysfunction-linked enzymes (arginase and PDE-5) and showed considerable antioxidant activity in a concentration-dependent manner. In view of this, we suggest the application of these results in the development of erectile dysfunction drugs in the pharmaceutical industry, with probable minimal or no adverse effect.

Sorghum [Sorghum bicolor (L.) Moench] leaf sheath dye protects against cisplatin-induced hepatotoxicity and oxidative stress in rats.

This study sought to determine the protective effect of dietary inclusion of sorghum leaf sheath dye on cisplatin-induced hepatotoxicity and oxidative stress in rats. Adult male rats were randomly divided into four groups with six animals in each group. Groups I and II were fed a basal diet, while groups III and IV were fed diets containing 0.5% and 1% sorghum leaf sheath dye, respectively, for 20 days before cisplatin administration. Hepatotoxicity was induced by a single dose of cisplatin (7 mg/kg body weight, i.p.), and the experiment was terminated at 3 days after cisplatin injection. The liver and plasma were studied for hepatotoxicity and antioxidant capacity. Cisplatin caused a significant (P<.05) alteration in plasma and liver enzymatic (catalase, glutathione-S-transferase [GST], and superoxide dismutase [SOD]) and nonenzymatic (glutathione [GSH] and vitamin C) antioxidant indices with a concomitant increase in the malondialdehyde (MDA) content; however, there was a significant (P<.05) restoration of the antioxidant status coupled with a significant (P<.05) decrease in the tissue MDA content, after consumption of diets containing sorghum leaf sheath dye. Furthermore, dietary inclusion of sorghum leaf sheath dye caused a marked reduction in the activities of alanine aminotransferase and aspartate aminotransferase after cisplatin administration. However, the ability of the dye to prevent significant cisplatin-induced alteration of both plasma and liver antioxidant indices suggests an antioxidant mechanism of action. Hence, this protective effect of Sorghum bicolor leaf sheath dye against cisplatin-induced hepatotoxicity in rats reflects its potential and beneficial role in the prevention of liver damage associated with cisplatin administration.

Dietary inclusion of sorghum (Sorghum bicolour) straw dye protects against cisplatin-induced nephrotoxicity and oxidative stress in rats.

CONTEXT: Sorghum straw (dried leaves and stem fiber) extracts and infusion are employed in the management of several ailments in folklore, and it is also a natural dye source used in food preparation. OBJECTIVE: This study sought to investigate the modulatory effect of dietary inclusion of Sorghum straw dye on cisplatin-induced nephrotoxicity and antioxidant status in rats. MATERIALS AND METHODS: Adult male rats were randomly divided into four groups of six animals each. Groups I (normal rats) and II (control rats) were fed with basal diet while Groups III and IV were fed with diets containing 0.5% and 1% sorghum straw dye, respectively. Nephrotoxicity was induced in Groups I-IV on the 20th day by the administration of a single dose of cisplatin solution (7 mg/kg body weight, i.p.) and the experiment was terminated 3 d after. Thereafter, the kidney and plasma of the rats were analyzed for kidney function (creatinine, urea, uric acid, and blood urea nitrogen) and antioxidant indices [superoxide dismutase (SOD), catalase, glutathione-S-transferase (GST), malondialdehyde (MDA), vitamin C, and reduced glutathione (GSH)]. RESULTS: The average feed intake of the rats in all the groups ranged from 9.0 to 9.5 (g/rat/day). Furthermore, the result indicated that administration of cisplatin caused significant (p < 0.05) elevation in plasma creatinine (2.2 mg/dL), uric acid (39.3 mg/dL), urea (81.4 mg/dL), and blood urea nitrogen (38.0 mg/dL) as well as a concomitant decrease in kidney antioxidant indices in control rats as against the normal rats. However, diets supplemented with 0.5 and 1.0% sorghum straw dye significantly reversed the plasma creatinine and the kidney antioxidant indices to near normal levels. DISCUSSION AND CONCLUSION: The study suggests that dietary inclusion of sorghum straw dye as colorants could protect against oxidative stress and cisplatin-induced nephrotoxicity.

Modulatory effects of dietary inclusion of garlic (Allium sativum) on gentamycin-induced hepatotoxicity and oxidative stress in rats.

OBJECTIVE: To investigate the ameliorative effect of dietary inclusion of garlic (Allium sativum) on gentamycin-induced hepatotoxicity in rats. METHODS: Adult male rats were randomly divided into four groups with six animals in each group. Groups 1 and 2 were fed basal diet while Groups 3 and 4 were fed diets containing 2% and 4% garlic respectively for 27 d prior to gentamycin administration. Hepatotoxicity was induced by the intraperitoneal administration of gentamycin (100 mg/kg body weight) for 3 d. The liver and plasma were studied for hepatotoxicity and antioxidant indices. RESULTS: Gentamycin induces hepatic damage as revealed by significant (P<0.05) elevation of liver damage marker enzymes (aspartate transaminase and alanine aminotransferase) and reduction in plasma albumin level. Gentamycin also caused a significant (P<0.05) alteration in plasma and liver enzymatic (catalase, glutathione and super oxygen dehydrogenises) and non-enzymatic (glutathione and vitamin C) antioxidant indices with concomitant increase in the malondialdehyde content; however, there was a significant (P<0.05) restoration of the antioxidant status coupled with significant (P<0.05) decrease in the tissues' malondialdehyde content, following consumption of diets containing garlic. CONCLUSIONS: These results suggest that dietary inclusion of garlic powder could protect against gentamycin-induced hepatotoxicity, improve antioxidant status and modulate oxidative stress; a function attributed to their phenolic constituents.

Anthocyanin - Rich Red Dye of Hibiscus Sabdariffa Calyx Modulates Cisplatin-induced Nephrotoxicity and Oxidative Stress in Rats.

This study sought to investigate the protective effect of dietary inclusion of Hibiscus sabdariffa calyx red dye on cisplatin-induced nephrotoxicity and antioxidant status in rats. Adult male rats were randomly divided into four groups of six animals each. Groups I and II were fed basal diet while groups III and IV were fed diets containing 0.5% and 1% of the dye respectively for 20 days prior to cisplatin administration. Nephrotoxicity was induced by a single dose intraperitoneal administration of cisplatin (7 mg/kg b.w) and the experiment was terminated 3 days after. The kidney and plasma were studied for nephrotoxicity and oxidative stress indices. Cisplatin administration caused a significant (P<0.05) increase in creatinine, uric acid, urea, and blood urea nitrogen (BUN) levels as well as kidney malondialdehyde (MDA) content, with concomitant decrease in kidney vitamin C and GSH contents. Furthermore, activities of kidney antioxidant enzymes such as, SOD, Catalase, and GST were significantly (P<0.05) altered in cisplatin administered rats. However, consumption of diets supplemented with the dye for 20 days prior to cisplatin administration protected the kidney and attenuates oxidative stress through modulation of in vivo antioxidant status. The determined anthocyanin content of the dye is 121.5 mg Cyanidin-3-rutinoside equivalent/100 g, thus, the observed nephroprotective effect of H. sabdariffa dye could be attributed to its anthocyanin content.