Mary Tolulope Olaleye

Rutin and quercetin show greater efficacy than nifedipin in ameliorating hemodynamic, redox, and metabolite imbalances in sodium chloride-induced hypertensive rats

Rutin and quercetin were investigated for their effects on blood pressure and antioxidant defense system of rats fed with 8% sodium chloride-supplemented diet (high salt diet) for 6 weeks. Animals fed with high salt diet demonstrated an increase in systolic, diastolic, pulse, and mean arterial blood pressures (p < 0.05) as well as lipid peroxidation but decreases in the activities of antioxidant enzymes compared with control group. Groups post-treated with rutin and quercetin for 2 weeks showed significant reversals in the values of these indices compared with the group fed with only the high salt diet but not post-treated. The high salt diet also led to significant increase in serum glucose, urea, creatinine, triglycerides, low-density-lipoprotein, and total cholesterol concentrations. Treatment with rutin and quercetin ameliorated the effects of high salt diet on these biochemical indices. The reference standard, nifedipin was less effective than rutin and quercetin. The results of this study highlight the risk of high salt consumption on cardiovascular health and the potent antioxidant and antihypertensive property of rutin and quercetin.

Antioxidant and antiulcer potential of aqueous leaf extract of Kigelia africana against ethanol-induced ulcer in rats

Ethnobotanical claims regarding Kigelia africana reported antiulcer properties as part of its medicinal application. In this work, aqueous leaf extract from K. africana was investigated for its phytochemical constituents and antiulcer potential against ethanol-induced ulcer in rats. The participation of oxidative stress on ethanol-induced ulcer and the potential protective antioxidant activity of K. africana extracts were investigated by determining vitamin C and thiobarbituric acid reactive species (TBARS) contents in the gastric mucosa of rats. The HPLC analysis showed the presence of gallic acid, chlorogenic acid, caffeic acid and also the flavonoids rutin, quercetin and kaempferol in the aqueous plant extract. Oral treatment with K. africana extract (1.75; 3.5; 7 and 14 mg/kg) one hour after ulcer induction with ethanol decreased in a dose dependent manner the ulcer index. Ethanol increased significantly stomachal TBARS levels and decreased vitamin C content when compared to the control animals. K. africana blunted the ethanol-induced oxidative stress and restored vitamin C content to the control levels. The present results indicate that the aqueous leaf extract from K. africana possesses antiulcer potential. The presence of flavonoids in plant extract suggests that its antiulcerogenic potential is associated with antioxidant activity. Of particular therapeutic potential, K. africana was effective against ethanol even after the induction of ulcer, indicating that it can have protective and curative effects against gastric lesion.

Comparative gastroprotective effect of post-treatment with low doses of rutin and cimetidine in rats

The anti‐ulcerogenic potentials of low doses of rutin and cimetidine in ethanol‐, acetic acid‐, and stress‐induced ulcers in rats have been evaluated and compared in this study. In each model, male Wistar rats were randomly divided into six groups (I–VI). Groups II–VI were administered 1 mL/100 g ethanol orally, 0.05 mL of 20% acetic acid submucosally or kept in a cold chamber for 6 h to induce ulcer in the ethanol‐, acetic acid‐, and stress‐induced ulceration model, respectively. Thereafter, group III was post‐treated with 300 mg/kg cimetidine and groups IV–VI with 20, 40, and 80 mg/kg rutin, respectively, while the control (group I) received distilled water in Tween 20. One hour after post‐treatment, all groups were killed and the gastric ulcer index was calculated. Malondialdehyde (MDA) level, vitamin C content, and glutathione peroxidase (GPx) activity were evaluated in the gastric mucosa of animals. Post‐treatment with rutin significantly reduced ulcerogen‐induced gastric damage in all models. This effect was significant at all dose levels compared with the ulcer‐induced groups. Rutin significantly reduced the MDA levels but increased the vitamin C content and GPx activity. Ulcer index and MDA level were highest in the ethanol‐induced ulcer model while vitamin C content and GPx activity were lowest in the stress‐induced ulcer model. The study showed that all three models of ulceration appeared to be linked to oxidative stress and also ascribed significant anti‐ulcerogenic potential to rutin especially at lower doses of 20–80 mg/kg.

Redox status and sperm characteristics in 1,4-dinitrobenzene-induced reproductive toxicity in Wistar rats

Abstract1,4-Dinitrobenzene (1,4-DNB) is a synthetic compound used in explosives, dyes, organic chemicals and the plastic industry. Oral and dermal exposure is a likely route for industrial workers and people living near ammunition plants. This study investigated the effect of 1,4-DNB on testicular and spermatozoan antioxidant systems as well as sperm characteristics of Wistar rats. Oral exposure of male Wistar rats to 50 or 75 mg/kg, or dermal exposure to 1000 or 2000 mg/kg, of 1,4-DNB for 14 days increased spermic and testicular hydrogen peroxide and lipid peroxidation levels accompanied by decreased activities of enzymic antioxidants. Exposure to 1,4-DNB also resulted in decrease in body weight gain, reduced testicular and epididymal weights, epididymal degeneration, decrease in sperm quantity and quality, and mild congestion of interstitial vessels and edema in the testes. These results reveal that individuals unduly exposed to 1,4-DNB risk induction of oxidative stress in the epididymis and testis, and associated reproductive deficits.

Improvement of 2-Vessel Occlusion Cerebral Ischaemia/Reperfusion-Induced Corticostriatal Electrolyte and Redox Imbalance, Lactic Acidosis and Modified Acetylcholinesterase Activity by Kolaviron Correlates with Reduction in Neurobehavioural Deficits

Background: Disruption of electrolyte, redox and neurochemical homeostasis alongside cellular energy crisis is a hallmark of cerebral ischaemia and reperfusion injury. Purpose: This study investigated the effect of kolaviron (KV) on cortical and striatal cation imbalance, oxidative stress and neurochemical disturbances as well as neurobehavioural deficits in animals subjected to bilateral common carotid artery occlusion (BCCAO)-induced ischaemia/reperfusion injury. Methods: KV was administered at a dose of 100 or 200 mg/kg to male Wistar rats 1 h before a 30 min BCCAO/4 h reperfusion (I/R). This was followed by neurobehavioral assessment and biochemical evaluations of cation levels, oxidative stress indicators, lactate dehydrogenase activity and acetylcholinesterase (AChE) activity in the brain of animals. Conclusion: KV significantly restored altered cortical and striatal Ca2+, Na+, K+ and Mg2+ levels, ameliorated redox imbalance, lactic acidosis and modified AChE activity caused by I/R injury. The favourable neurobehavioural effects of KV correlated with biochemical outcomes. The pharmacological potential of KV in the treatment and management of ischemic stroke and allied pathological conditions via multiple targets (neurotransmitter metabolism, bioenergetic failure and ionic homeostasis) is highlighted by the study.

The para isomer of dinitrobenzene disrupts redox homeostasis in liver and kidney of male wistar rats

Background Para-Dinitrobenzene (p-DNB) is one of the isomers of dinitrobenzene which have been detected as environmental toxicants. Skin irritation and organ toxicities are likely for industrial workers exposed to p-DNB. This study evaluated the effect of sub-chronic exposure of rats to p-DNB on cellular redox balance, hepatic and renal integrity. Methods Forty eight male Wistar rats weighing 160–180 g were administered 50, 75, 1000 and 2000 mg/kg b.wt (body weight) of p-DNB or an equivalent volume of vehicle (control) orally and topically for 14 days. After the period of treatment, the activities of kidney and liver catalase (CAT), alkaline phosphatase (ALP) and superoxide dismutase (SOD) as well as extent of renal and hepatic lipid peroxidation (LPO) were determined. Serum ALP activity and plasma urea concentration were also evaluated. Results Compared with control animals, p-DNB -administered rats showed decrease in the body and relative kidney and liver weights as well as increased renal and hepatic hydrogen peroxide and lipid peroxidation levels accompanied by decreased superoxide dismutase and catalase activities. However, p-DNB caused a significant increase in plasma urea concentration and serum, liver and kidney ALP activities relative to control. In addition, p-DNB caused periportal infiltration, severe macro vesicular steatosis and hepatic necrosis in the liver. Conclusions Our findings show that sub-chronic oral and sub-dermal administration of p-DNB may produce hepato-nephrotoxicity through oxidative stress.

Cardiotoxicity and Cardioprotective Effects of African Medicinal Plants

Cardiac health is vital and any dysfunction of the heart portends serious consequences for the entire organism. Africa’s rich biodiversity includes many medicinal plants with putative or documented claims for cardioprotective and cardiotoxic properties. Cardioactive plants exert beneficial or adverse effect on humans and veterinary animals. The discovery of the drug digoxin, which has its root in Digitalis spp., contributed in escalating interest in the exploration of medicinal plants for cardioactive properties, especially as remedies or sources of novel drugs for the treatment of heart-related diseases. Profiling the bioactivities of medicinal plants will enhance their safe and effective use and delineate areas for further scientific research. This chapter focuses on cardioactive medicinal plants from Africa including some well-known cardioactive plants which were introduced to Africa from their native regions. Methods used in screening medicinal plants for cardioprotective or cardiotoxic effects also are discussed.

Parinari curatellifolia seed flavonoids protect against Triton-induced dyslipidemia and atherogenicity in rats

Parinari curatellifolia seed flavonoid extract (PFE) and crude methanol extract (PME) were investigated for their effects on Triton X‐100 (TRT; 200 mg/kg i.p.)‐induced dyslipidemia in rats.

Angiotensin-1-converting enzyme inhibition, antioxidant activity, and modulation of cerebral Na+/K+ ATPase by free phenolics of African locust bean (Parkia biglobosa)

To investigate the antioxidant activities and effects of free phenols (FPPB) and bound phenols (BPPB) of Parkia biglobosa leaves on some enzymes of neuro‐cardiovascular relevance.