Nigerian Journal of Physiological Sciences最新文献

Many biological tissues and organs are affected by the toxicity of potassium bromate (KBrO3). The purpose of this study was to evaluate the Parkia Biglobosa (P. Biglobosa) seed's ability to treat KBrO3-induced haematological parameters derangement. After becoming accustomed to the lab, 24 Wistar rats were randomly assigned to groups A, B, C, and D. Group A was given distilled water to drink. Each of the groups in B, C, and D got 100 mg/kg of KBrO3. Also, for 28 days prior to sacrifice, groups C and D received 100 and 200 mg/kg of P. biglobosa, respectively. Blood was drawn, and the haemogram was examined using a haematology autoanalyzer. When KBrO3 was added compared to the control, the results showed a substantial decrease in both haemoglobin concentration, packed cell volume (PCV), and red blood cell count from 17.262.84 g/dL, 39.732.58%, 5.120.83 x 1012/L to 13.251.25 g/dL, 27.931.44%, and 3.470.22 x 1012/L, respectively. The effect of KBrO3 was dose-dependently counteracted by P. biglobosa treatments of 100 and 200 mg/kg body weight. However, there was no discernible difference in the MCV, MCH, and MCHC values between the control and test groups. Similar to how P. biglobosa reduced the effects of KBrO3 in a dose-dependent manner, P. biglobosa also induced a substantial decrease in white blood cell count, its differentials, and platelet counts (P0.05). KBrO3-induced deranged haematological parameters were mitigated by Parkia biglobosa in a dose-dependent manner. Care must be taken with the consumption of this addictive due to its numerous toxic effects. However, consumption of P. biglobosa, a tropical homemade food is recommended for families to benefit from the barrage of its health benefits. This will also alleviate the toxic effect of KBrO3 if consumed inadvertently. Human clinical trial is needed to substantiate these findings.

Rauvolfia vomitoria is a medicinal plant that has been implicated by various scientific studies as possessing strong anti-diabetic action; however, the mechanism of action is lacking. Hence this study investigated the anti-diabetic mechanisms of action of Rauvolfia vomitoria through in vitro and in vivo studies. In the in vitro study, the α-amylase and α-glucosidase inhibitory activities of hydromethanolic Rauvolfia vomitoria leaf extract were investigated in comparison with acarbose; while in the in vivo, the effect of the extract on plasma insulin levels of normal and streptozotocin-induced diabetic wistar rats were investigated in comparison with glyburide. Results from the in vitro study showed the percentage inhibition of α-amylase by the extract (100 mg/ml) to be 62.28 (4.73) with an IC50 values of 74.35 mg/ml, while acarbose had a percentage inhibition and IC50 values of 72.81 (2.52) and 66.05μg/ml, respectively. The percentage inhibition of α-glucosidase by the extract (100 mg/ml) was 79.63 (4.09) and an IC50 values of 58.85 mg/ml, while acarbose had a percentage inhibition and IC50 values of 82.11 (1.84) and 56.79μg/ml, respectively. From the in vivo study, the result showed that the extract caused a dose and treatment-duration dependent significant (P<0.05) increase in the plasma insulin levels of streptozotocin-induced diabetic rats in a manner comparable to glyburide. From the results of these investigations, it is therefore concluded that Rauvolfia vomitoria leaf effect its anti-diabetic actions via two separate mechanisms; the plasma insulin increasing mechanism and the α-amylase and α-glucosidase inhibitory mechanism. Keywords: Rauvolfia vomitoria leaf extract, α-amylase, α-glucosidase, plasma insulin, acarbose, glyburide.

Cadmium, despite being an environmental pollutant has a wide range of applications and causes oxidative damage to the testes and impairment of male reproductive function. PurXcel, a polyherbal remedy is said to be rich in antioxidants and improves fertility. But there are no scientific records of its effect on Cadmium-induced male reproductive impairment, hence this study. Twenty male wistar rats were randomly assigned into 4 groups of 5 rats each namely control, Cadmium-only, PurXcel-only and Cadnium+PurXcel groups. Treatment with PurXcel lasted for 28 days after which blood samples were collected and testes and epididymis harvested for evaluation of relevant parameters. Body weight changes (BWC) as well as weights of testes and epididymis were significantly reduced in Cadmium-only group (P<0.05 each) compared with the control. PurXcel given alone and in combination with Cadmium significantly increased (P<0.05) the BWC as well as testicular and epididymal weights in comparison with the Cadmium-only group. Sperm function indices (count, motility, viability and normal morphology) and reproductive hormones (GnRH, FSH, LH and testosterone) activities were significantly decreased (P<0.05) in the Cadmium-only group compared with the control but higher in all treated groups (P<0.05) compared with Cadmium-only group. Testicular activities of MDA and TBARS were significantly increased in the Cadmium-only group compared with control (P< 0.05) but reduced in treated groups (P< 0.05) compared with Cadmium-only group. The activities of testicular SOD, GPx and Catalase as well as total antioxidant capacity were significantly reduced in the Cadmium-only group compared with control (P<0.05) but increased in the treated groups compared with Cadmium-only group (P<0. Testicular morphometric parameters showed decreases in Sertoli cell count, Leydig cell count, Johnson's score, seminiferous tubules diameter and germinal epithelial height (P<0.05) in the Cadmium-only group compared with the control but which were significantly higher in the Cadmium+PurXcel than in the Cadmium-only groups (P<0.05). A section of the testes also revealed mainly empty luminal cavities and scanty intervening interstitium in the Cadmium-only group compared with the control. The PurXcel-only and Cadmium+PurXcel groups, have dense intervening interstitium and luminal cavities filled with mature sperm cells. There were loosely packed epididymis and which were mainly empty in the Cadmium-only group whereas the epididymis of the PurXcel-only and Cadmium+PurXcel groups have a densely packed epididymis filled with spermatozoa. We conclude that PurXcel improves Cadmium-induced male reproductive toxicity and given alone, improves testicular antioxidant status in Wistar Rats.

Background: Smoking is associated with dysregulation of the antioxidant system and addiction.

Aim: This study sought to ascertain the effect of Nigella Sativa (NS) oil on the antioxidant system, nicotine/tobacco addiction as well as the expressions of α4β2 nicotinic (nAChR) and dopamine type-2 (DRD2) receptors in selected brain regions of the rat.

Methods: Thirty male Sprague-Dawley rats were divided into 6 groups comprising of vehicle-treated control, NS oil only, Smoke only, Smoke + NS oil, Nicotine only and Nicotine + NS oil. Animals were passively exposed to cigarette smoke or nicotine vapour for 12 weeks, however, NS oil treatment commenced from 9th-12th week of the experimental duration.

Results: Nicotine vapour and cigarette smoke-induced increase in cotinine level were significantly ameliorated by NS treatment. Cigarette smoke or nicotine vapour exposure significantly (p<0.05) decreased the level of antioxidant enzymes while increasing malondialdehyde level in the brain homogenates of the rats.  Administration of NS oil significantly (p<0.05) reversed the reduced antioxidant level. Cigarette-smoke also significantly increased α4-nAChR expression in the frontal cortex and olfactory bulb compared to control. Nicotine vapour significantly increased DRD2 expression only in the olfactory cortex. NS oil administration reduced both the cigarette-smoke-induced increase in α4-nAChR and nicotine vapour-induced increase in DRD2 gene expression only in the olfactory cortex.

Conclusion: Findings from this study suggest that NS oil improves brain antioxidant status while ameliorating nicotine vapour and cigarette smoke addiction through down-regulation of α4-nAChR and DRD2 gene expressions in discrete brain regions in Sprague-Dawley rats.

The African giant rat, AGR (Cricetomys gambianus) is a unique rodent known for its keen sense of smell which has enabled its use in the diagnosis of tuberculosis and demining activities in war torn countries. This keen sense of smell and the ability to navigate tight spaces are skills modulated by the olfactory bulb and cerebellum. While the brain is generally susceptible to environmental pollutants such as heavy metals, vanadium has predilection for these two brain regions. This work was thus designed to investigate the probable neurotoxic effect of vanadium on the neuronal cytoarchitecture of the cerebellum and olfactory bulb in this rodent. To achieve this, twelve adults male AGRs were divided into two groups (vanadium and control groups) and were given intraperitoneal injections of 3mg/kg body weight sodium metavanadate and normal saline respectively for 14 days. After which they were sacrificed, and brains harvested for histological investigations using Nissl and Golgi staining techniques. Results from our experiment revealed Purkinje cell degeneration and pyknosis as revealed by a lower intact-pyknotic cell (I-P) ratio, higher pyknotic Purkinje cell density and poor dendritic arborizations in the molecular layer of the cerebellum in the vanadium treated group. In the olfactory bulb, neuronal loss in the glomerular layer was observed as shrunken glomeruli. These neuronal changes have been linked to deficits in motor function and disruption of odor transduction in the olfactory bulb. This work has further demonstrated the neurotoxic effects of vanadium on the cerebellum and olfactory bulb of the AGR and the likely threat it may pose to the translational potentials of this rodent. We therefore propose the use of this rodent as a suitable model for better understanding vanadium induced olfactory and cerebellar dysfunctions.

Depression is a mental disorder characterized by depressive episodes, such as low mood, low self-esteem, feeling of guilt, and poor concentration. Depression has a high comorbidity with cognitive impairments. Studies have shown that cinnamon has anti-inflammatory antiviral, antihypertensive, antioxidant and anti-diabetic potentials. Therefore, the aim of the research was to assess the antidepressant effect of cinnamon on open-space forced swim-induced depression in mice. Twenty-five (25) Swiss albino mice were grouped into five groups (n=5). Group I: control (negative control) exposed to open-space forced swim test (OSFST) without any treatment, Groups II, III and IV received graded doses of Cinnamon 12.5, 25, and 50 mg/kg, group 5 (positive control) received fluoxetine 20 mg/kg orally. The animals were subjected to OSFST, Open Field Test (Line Crossing) and Novel Object Recognition Test (NORT). Administration of cinnamon showed decreased immobility time (behavioural despair) in OSFST compared to control and fluoxetine groups (p < 0.05). However, no statistically significant effect was observed in line crossing (locomotor activity) and the discrimination ratio of NORT (non-spatial short-term memory) between cinnamon administered groups and the control group. In conclusion, cinnamon has shown antidepressant-like effect in open-space forced swim-induced depression in mice. Keywords: Cinnamon, Depression, Cognitive impairment, Immobility time, Behavioural despair.

Dimethyl nitrosamine (DMN), a potent hepatotoxin, exerts carcinogenic effects and induces hepatic necrosis in experimental animals via CYP2E1 metabolic activation, and generation of reactive oxygen species (ROS). Protocatechuic acid (PCA), a plant-based simple phenolic compound and potent antioxidant, has been shown to affect the development of neoplasia in the rat liver and inhibit the initiation or progression phases of most cancers. In this study, the modulatory effects of PCA on DMN-induced hepatotoxicity, oxidative stress, inflammation, and selected phase I xenobiotic metabolizing enzymes were investigated in male Wistar rats. This study assessed biomarkers of hepatic injury (alanine transaminase, aspartate aminotransferase, alkaline phosphatase, and gamma- glutamyl transferase); oxidative stress (hydrogen peroxide concentration, lipid peroxidation, and reduced glutathione levels); measured activities of antioxidant enzymes (catalase, sodium dismutase, glutathione peroxidase, glutathione S-transferase); and inflammation (Tumor necrosis factor (TNF)-α, interleukin-1-Beta (IL-1β) and iNOS). The results of our investigation demonstrated that pretreatment with PCA at 50 and 100 mg/kg body weight p.o. reduced DMN (20 mg/kg bw) i.p. mediated hepatic injury, oxidative stress, and inflammation in a dose-dependent manner. In addition, the activities of phase I metabolizing enzymes were significantly induced except for aminopyrine-N-demethylase in the DMN-treated rats when compared with the DMN alone control group. This induction was also reversed by pre-treatment with PCA. The result of this study suggests that PCA is hepatoprotective against DMN-induced hepatic damage by its ability to suppress oxidative stress, inflammation, and modulate the activities of the selected phase I drug metabolizing enzymes. Thus, PCA may prove useful in combating DMN-induced hepatic damage.

 Cardiovascular diseases are the leading causes of death globally resulting in 17-19 million death every year. The search for an effective medicine to manage cardiovascular disorder without any side effect has led to the use of traditional based medicine. 75% of the world's population has been reported to depend on traditional medicine as their basic form of health care and this has resulted to the use of herbal medicine in the treatment and management of metabolic diseases. The study evaluated the effect of methanolic extract of Ricinus communis on DDVP-induced cardiotoxicity in male Wistar rats. Thirty-two (32) male Wistar rats were randomly divided into four groups of eight (8) rats each. Group A served as control rats, received 10mL/Kg of dimethyl sulfoxide (DMSO) and distilled water solution (vehicle) for six weeks. Group B served as DDVP-induced rats and were exposed to DDVP (15 minutes daily) for 3 weeks without any treatment. Group C rats received DDVP as in group B and then administered 300mg/kg of R. communis extract for 42days. While Group D rats were administered 300mg/kg of R. communis extract daily, for 6 weeks in addition to normal feed and water. Exposure to DDVP caused significant cardiac dysfunction evidence by alteration in cardiovascular variables and electrocardiac function, compromised lipid profile and reduced antioxidant enzymes. However, treatment with methanolic extract of Ricinus communis improved antioxidant defense system, attenuate hemodynamic impairment and left ventricular dysfunction, as well as inhibit lipid peroxidation and prevent hyperlipidemia in rats. In addition, histopathology observation showed that Ricinus communis extract was able to regenerate the myocardial injury caused by exposure to dichlorvos. In conclusion, Ricinus communis exhibited cardioprotective properties and may be a potential remedy for cardiovascular diseases with low risk of toxicity.

Lead (Pb) toxicity constitutes a major health hazard to both humans and animals especially in the developing countries. It is a ubiquitous environmental contaminant found in the air essentially because of unregulated mining and other industrial activities. Lead can be found naturally in the soil thus, contaminating crops for human and animal food, as well as run-off water and air pollution. Intensively and extensively reared domestic chickens are exposed to contamination via inhalation and ingestion of contaminated food materials. Naringin, a product from citrus plant has been described to possess excellent metal chelating ability. Naringin is rich in flavonoid with attendant antioxidant, anti-autophagy, anti-inflammatory, hepatoprotective and cardio-nephroprotective properties. This study was conducted to investigate the hepatoprotective and modulation of oxidative stress in commercial cockerel chickens by Naringin. Thirty-six commercial cockerel chickens were randomly assigned into six groups A-F of six birds each viz: Group A served as control group while groups B, C, and D received Lead acetate at 300 ppm via drinking water continuously till the end of the experiment. In addition, groups C and D were treated with Naringin at 80 mg/kg and 160mg/kg, respectively, via oral gavage for 8 weeks. Groups E and F were administered naringin only at 80mg/kg and 160mg/kg respectively for eight weeks. Pb toxicity induced degenerative changes in the histological sections as well as, higher expression of hepatic caspase 3 as shown by immunohistochemistry. There was increased oxidative stress markers (H2O2, MDA) and depletion of the antioxidant defense system markers SOD, GPx, GSH, and GST. It concluded that Co- treatment with Naringin ameliorated oxidative stress, enhanced antioxidant defense system, reduced the expression of hepatic caspase 3 thus, offering protection against lead acetate-induced derangements in the liver of commercial cockerel chickens.

Epilepsy is a chronic disease of the brain characterized by seizures. The currently available anticonvulsants only treat symptoms with serious adverse drug reactions. Therefore, there is need for new therapeutic intervention that will prevent epileptogenesis with greater therapeutic success. Quercetin (QT) is a flavonoid with known neuroprotective and anti-inflammatory properties. The study aimed to investigate its effects against pentylenetetrazole (PTZ)-induced seizures. Animals were divided into four groups (n = 10). Group 1(control) only received vehicle (10 mL/kg), group 2 received vehicle, groups 3 and 4 received QT 12.5 mg/kg and 25 mg/kg respectively. Sixty minutes after treatments, animals in groups 2 to 4 were injected with sub-convulsive dose of pentylenetetrazole (35 mg/kg, i.p.) on every alternate day (48±2h) for 21 days. The mice were observed for 30 minutes after each PTZ injection for seizure activity. Brain samples were collected for biochemical assays. Administration of PTZ caused significant increase in the intensity of seizures, neuronal degeneration and level of proinflammatory cytokines in animals compared to control. These behavioural alterations were attenuated significantly by QT (12.5 and 25 mg/kg). The PTZ-induced increase in IL-12, TNF-α and IFN-ɣ were significantly reduced by pre-treatment with the QT (12.5 and 25 mg/kg, p.o). Quercetin also reduced neuronal loss compared to control. Quercetin attenuates seizures in kindled mice and reduces neuroinflammation and neurodegeneration. This neuroprotective effect may be attributed to its ability to inhibit inflammatory mediators in the brain.