Haematoprotective and Hepatoprotective Effects of Methanolic Leaf Extract of Parquetina nigrescens on Arsenic trioxide-induced Toxicity in Male Wistar Rats.

This study was designed to investigate the phytochemical composition and protective effects of methanol extract of Parquetina nigrescens leaf (MEPL) in male Wistar rats. Phytochemical screening, in vitro antioxidant assay, gas chromatography-mass spectrometry (GC-MS) and LD50 were determined. Forty male Wistar rats were grouped into eight and orally treated for 54 days as follows: Group 1 (10% tween 80), Group 2 (3 mg/kg As2O3) Groups 3, 4 and 5 (250, 500 and 1000 mg/kg MEPL) and groups 6, 7 and 8, (250 mg/kg+As2O3, 500 mg/kg+As2O3 and 1000 mg/kg+As2O3). The animals were sacrificed on day 55 under anaesthesia. Blood was collected by cardiac puncture for heamatological studies. Liver concentrations of malondialdehyde (MDA), superoxide dismutase (SOD), aspartate aminotransferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) activities were determined spectrophotometrically. Liver histology was also assessed. Flavonoids, tannin, alkaloids, saponin, and anthraquinone were present in MEPL, also, MEPL scavenged 2,2 diphenyl-1-picrylhydrazyl hydrate (DPPH) and Azino-bis-3-ethylbenzthiazoline-6-sulphonic acid radical (ABTS+). The IC50 of MEPL required to chelate metal was also low. The GC-MS revealed the presence of 24 essential oil. The LD50 was > 5000 mg/kg. Packed cell volume and red blood cell count were significantly reduced in 1000 mg/kg MEPL group, white blood cell count and SOD activity reduced (P<0.05) in 3 mg/kg As2O3 when compared with control but increased in groups co-treated with As2O3 and 250, 500 or 1000 mg/kg + As2O3. MDA concentration, AST, ALT and ALP activities increased significantly in 3 mg/kg As2O3 group but decreased (P<0.05) in groups co-treated with As2O3 and 250, 500 or 1000 mg/kg. The methanol extract of Parquetina nigrescens leaf in male Wistar rats has antioxidant, hepatoprotective and white blood cell protective effects.

Haematological and biochemical changes in arsenic trioxide-induced toxicity in Wistar rats treated with methanol extract of Parquetina nigrescens leaf.

This study was designed to investigate the phytochemical composition and protective effects of methanol extract of Parquetina nigrescens leaf (MEPL) in male Wistar rats. Phytochemical screening, in vitro antioxidant assay, gas chromatography-mass spectrometry (GC-MS) and LD50 were determined. Forty male Wistar rats were grouped into eight and orally treated for 54 days as follows: Group 1 (10% tween 80), Group 2 (3 mg/kg As2O3) Groups 3, 4 and 5 (250, 500 and 1000 mg/kg MEPL) and groups 6, 7 and 8, (250 mg/kg+As2O3, 500 mg/kg+As2O3 and 1000 mg/kg+As2O3). The animals were sacrificed on day 55 under anaesthesia. Blood was collected by cardiac puncture for heamatological studies. Liver concentrations of malondialdehyde (MDA), superoxide dismutase (SOD), aspartate aminotransferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) activities were determined spectrophotometrically. Liver histology was also assessed. Flavonoids, tannin, alkaloids, saponin, and anthraquinone were present in MEPL, also, MEPL scavenged 2,2 diphenyl-1-picrylhydrazyl hydrate (DPPH) and Azino-bis-3-ethylbenzthiazoline-6-sulphonic acid radical (ABTS+). The IC50 of MEPL required to chelate metal was also low. The GC-MS revealed the presence of 24 essential oil. The LD50 was > 5000 mg/kg. Packed cell volume and red blood cell count were significantly reduced in 1000 mg/kg MEPL group, white blood cell count and SOD activity reduced (P<0.05) in 3 mg/kg As2O3 when compared with control but increased in groups co-treated with As2O3 and 250, 500 or 1000 mg/kg + As2O3. MDA concentration, AST, ALT and ALP activities increased significantly in 3 mg/kg As2O3 group but decreased (P<0.05) in groups co-treated with As2O3 and 250, 500 or 1000 mg/kg. The methanol extract of Parquetina nigrescens leaf in male Wistar rats has antioxidant, hepatoprotective and white blood cell protective effects.

Hepatoprotective effects of Quassia amara stem bark against cadmium-induced toxicity in male Wistar rats.

OBJECTIVES: The liver is one of the primary biorepositories of cadmium (Cd) and it has been implicated in the pathogenesis of hepatic diseases. Quassia amara stem bark has been reputed to have strong antimalarial, antimicrobial, antiulcerative and amoebicidal properties. This study aims to determine the effects of Q. amara on Cd-induced hepatotoxicity and lipid profile in male Wistar rats. METHODS: The animals were divided into three groups of five animals each. Group 1 served as control while group 2 received Cd (5 mg/kg) for 4 weeks. Prior to Cd treatment, group 3 was treated with Q. amara extract (200 mg/kg) for 2 weeks and received the Q. amara and Cd simultaneously for 4 weeks. RESULTS: Cadmium caused significant increase in serum total cholesterol and low-density lipoprotein (LDL) as well as increased hepatic malondialdehyde (MDA) when compared with the control group. On the other hand, Cd caused a decrease in serum high-density lipoprotein (HDL) and hepatic superoxide dismutase (SOD) when compared with control. However, treatment with Q. amara prevented Cd-induced changes in the lipid profile, augmented Cd-induced decline in SOD and also ameliorated the Cd-induced increase in MDA. Catalase level was however comparable across the groups. CONCLUSIONS: Q. amara ameliorated the Cd-induced damage to liver by preventing dyslipidemia and oxidative damage in the hepatic tissue.

Carpolobia lutea Root Extract Improved Steroidogenic Activity in Male Wistar Rats Exposed to Cadmium.

Cadmium (Cd) is known to affect reproductive functions adversely. Carpolobia lutea is a protective herbal derivative due to its antioxidant potential. This study investigates the steroidogenic activities of methanol extract of Carpolobia lutea root on cadmium-induced reproductive toxicity in male Wistar rats. Carpolobia lutea root was obtained in Ijare via Akure. The plant was authenticated at the herbarium of Forestry Research Institute of Nigeria (FRIN), Ibadan, Nigeria, with FHI number 109784. The methanol extract Carpolobia lutea root (MCL) was obtained by Soxhlet extraction. Thirty male Wistar rats (150-170g) were used in this study (n=5) and treated as follows: Control, Cd (2 mg/kg), Cd+MCL (2 mg/kg+100 mg/kg), Cd+MCL (2 mg/kg+200 mg/kg), MCL (100 mg/kg), and MCL (200 mg/kg). The extract was administered orally for eight weeks, and a single dose of 2 mg/kg Cd was given intraperitoneally. Serum Follicle Stimulating Hormone (FSH), Luteinizing hormone (LH), testosterone levels, testicular hydroxysteroid dehydrogenases (HSDs) activities and Steroidogenic Acute Regulatory protein (StAR) expression were evaluated. Data were subjected to descriptive statistics and analysed using ANOVA at p<0.05. Serum FSH, LH, testosterone levels, 3ß-HSD, 17ß-HSD activities and StAR expression were significantly reduced (p<0.05) in Cd group. The co-administration of Cd with MCL (200mg/kg) significantly increased (p<0.05) serum FSH, LH, testosterone levels, 3ß-HSD, 17ß-HSD activities and StAR expression when compared with Cd group. Carpolobia lutea root extract improved steroidogenic activity in male Wistar rats exposed to cadmium.

Mechanisms of inhibitory activity of root extract of Carpolobia lutea G. Don on in vitro contractile responses of rabbit corpus carvernosum.

INTRODUCTION: Carpolobia lutea root extract (CLRE) has been reported to enhance penile erection. However, the mechanism involved is poorly understood. We investigated in vitro mechanisms of CLRE action on contractile activity of rabbit corpus cavernosum (CC). METHODS: Corpus cavernosum strips from four healthy male New Zealand rabbits (2.5-3.0kg) were mounted on an organ chamber and contracted with phenylephrine (PE) (10-9 to 10-5M) and Potassium Chloride (KCl) (10-50mM) before treatment with various concentrations of CLRE (0.1-1.2mg/ml). Interactions between CLRE and a Nitric Oxide Synthase (NOS) inhibitor (N-nitro-l-arginine methyl ester - l-NAME 10-4M); guanylyl cyclase inhibitors (Oxalodiazolo 4,3-a quinoxalin-1-one - ODQ 10µM, 20µM, 30µM), and (methylene blue 10-30µM); a cyclooxygenase inhibitor (10-4M indomethacin); potassium-channel inhibitors (100µM tetraethyl ammonium TEA), (100ηM apamin) and (glibenclamide 10µM and 20µM); and a calcium-channel inhibitor (-10-4M nifedipine) were investigated. RESULTS: Maximal contractions of KCl and PE contracted CC strips were significantly reduced in a concentration-dependent manner (40.8±3.6% and 38.6±4.0% from 64.6±2.9% and 98.1±4.2% respectively). Relaxant effect of CLRE was significantly reduced by ODQ (38.6±4.0% to 6.4±1.3% and 38.6±4.0% to 7.2±1.2%), nifedipine (38.6±4.0% to 21.1±2.7%) and glibenclamide (40.8±3.6% to 31.5±3.3%). However l-NAME, indomethacin, methylene blue, TEA and apamin did not inhibit relaxation by CLRE. CONCLUSION: Concentration-dependent relaxant effect of CLRE in rabbit CC involves the soluble guanylate cyclase/cyclase Guanosine Monophosphate system, and activation of ATP-dependent K+ channels.

Saccharum officinarum juice alters reproductive functions in male Wistar rats.

Infertility is a problem across almost all cultures and societies. Problems in the male partner, especially as a result of unhealthy dietary habits, are the commonest single group of course. Many populations, therefore, tend more toward the use of natural dietary substitutes opined to proffer less risk to reproductive functions and more health benefits. Saccharum officinarum juice (SOJ) is a widely consumed, energy-rich, nutritious substance that has many minerals and enzymes. Saccharum officinarum plant was reported to have anti-thrombosis, anti-inflammatory and immune-stimulatory activities. This study evaluated the reproductive effects of S. officinarum juice in male Wistar rats. A sugarcane press juicer was used to extract S. officinarum juice. Twenty male Wistar rats (100-120 g) grouped into four (n = 5) received 1.0 mL/kg/day distilled water (control), and 1.0, 3.2 and 10.0 mL/kg/day of fresh S. officinarum juice once daily for 8 weeks via gavage. Sperm analysis, histology of testes and epididymides were evaluated by microscopy. Enzyme-linked immunosorbent assay (ELISA) was used in assessing the serum levels of luteinizing hormone, follicle-stimulating hormone and testosterone. Data were analyzed using the analysis of variance at a significance of p < 0.05. SOJ increased fasting blood glucose levels in 3.2 and 10.0 mL/kg groups. The 10.0 mL/kg juice caused a significant increase in testosterone level and sperm count, and it also increased the percentage of aberrant sperm and decreased sperm viability. Saccharum officinarum juice impaired the histological integrity of the testes and epididymides. Thus, S. officinarum juice adversely altered the reproductive functions of male Wistar rats by reducing sperm quality and disrupting testicular architecture.

Effects of the methanol root extract of Carpolobia lutea on sperm indices, acrosome reaction, and sperm DNA integrity in cadmium-induced reproductive toxicity in male Wistar rats.

OBJECTIVE: Oxidative stress is a mechanism of cadmium-induced reproductive dysfunction. Carpolobia lutea is a free radical scavenger. Our study investigated the potential protective effects of Carpolobia lutea root methanol extract against cadmium-induced reproductive toxicity. METHODS: We obtained the Carpolobia lutea root in Akure, and it was authenticated at the Forestry Research Institute of Nigeria (FRIN) herbarium, Ibadan, Nigeria, with FHI number 109784. We used Soxhlet extraction to obtain its methanol extract. We used thirty male Wistar rats (150-170g) in this study, (n=5 per group), and treated them as follows: Control (1 ml/kg normal saline), Cd (2 mg/kg), Cd+MCL (2 mg/kg+100 mg/kg), Cd+MCL (2 mg/kg+200 mg/kg), MCL (100 mg/kg), MCL (200 mg/kg). We administered Carpolobia lutea orally for 8 weeks. We administered a single dose of 2 mg/kg of cadmium intraperitoneally. We assessed the sperm profile using a computer-aided sperm analyzer. Under microscopy, we determined the sperm acrosome reaction and the DNA damage. We measured the seminal fructose level using spectrophotometry, and the data were analyzed using ANOVA at p<0.05. RESULTS: Cd+MCL (2mg/kg+200 mg/kg) significantly increased sperm count (339.0±25.0 vs. 29.0±4.5 million/mL), motility (80.0±0.2 vs. 55.0±4.9%), viability (68.7±2.7 vs. 31.3±2.9%) and decreased abnormal sperm (28.3±1.7 vs. 43.3±2.5%), relative to the cadmium group. Cd+MCL (2mg/kg+200 mg/kg) significantly increased acrosome reaction (68.0±7.5 vs. 15.2±2.4%) and seminal fructose level (0.49±0.06 vs. 0.28±0.06 mmol/L) relative to the cadmium group. Cd+MCL (2mg/kg+200 mg/kg) significantly decreased sperm DNA damage (14.1±1.6 vs. 35.9±5.3%) in relation to the cadmium group. CONCLUSIONS: Carpolobia lutea root extract improves the sperm variables of rats exposed to cadmium.

Saccharum officinarum molasses adversely alters reproductive functions in male wistar rats.

The widely reported anti-androgenic effects of refined sugar led to the exploration of safer alternatives. Saccharum officinarum molasses (SOM), a byproduct of sugar processing is gaining popularity as a substitute. This study investigated the effects of SOM and compared them to those of refined sugar on male reproductive functions. Blackstrap® Saccharum officinarum molasses were subjected to phytochemical screening and proximate analysis and fractionated to obtain methanol (SOMMF) and aqueous (SOMAqF) fractions. Twelve groups (n = 5) of adult male Wistar rats received distilled water (Control); 0.8, 2.5, 7.9 g/kg SOM; 0.0064 g/kg sugar (Dangote®); 0.0064 g/kg sugar+7.9 g/kg SOM; 1.0, 3.2, 10.0 g/kg SOMMF and 0.6, 2.0, 6.4 g/kg SOMAqF, respectively. Administrations were done daily by oral gavage for eight weeks. Sperm profile and testicular and epididymal histology were assessed using microscopy. Serum testosterone was quantified using ELISA. Testicular malondialdehyde (MDA) was assayed by spectrophotometry. Data were analyzed using ANOVA at p < 0.05 significance. Sperm count and viability reduced with 7.9 g/kg SOM, Sugar, 3.2 and 10.0 g/kg SOMMF, 2.0 and 6.4 g/kg SOMAqF. Abnormal sperms increased with 7.9 g/kg SOM, Sugar, 2.0 and 6.4 g/kg SOMAqF. Testosterone level reduced with 6.4 g/kg SOMAqF. Testicular MDA increased with SOM, 3.2 and 10.0 g/kg SOMMF and 6.4 g/kg SOMAqF. Seminiferous tubules and epididymal ducts of 7.9 g/kg SOM, Sugar and SOMAqF-treated rats showed anomalies. Saccharum officinarum molasses altered testicular and epididymal integrity via lipid peroxidation, thus reducing sperm quality and androgen levels in male Wistar rats.

Experimental dapsone administration induces infertility in male Wistar rats: Mechanisms and clinical implications.

Dapsone (4, 4'-diaminodiphenylsulfone, DDS) is a potent anti-inflammatory and antibacterial compound which has been used in the treatment of leprosy, vasculitis and dermatitis herpetiformis, lupus erythematosus profundus and even as an antimalarial in combination with proguanil. This study investigated the effect of the administration of dapsone on the reproductive activities of male rats using in vivo and in vitro techniques. In the in vivo study, dapsone was administered orally to male Wistar rats for 5 days or 6 weeks after which their body weight, relative reproductive organ weights, sperm parameters and reproductive hormones were determined while testicular and epididymal histology were also assessed. Data were compared using analysis of variance and Students-Newman-Keuls multiple comparison test. For the in vitro study, Sertoli cells were cultured and treated with varying doses of dapsone at different durations, thereafter Sertoli cell viability and nuclei integrity were determined. Also, the genetic expressions of Glial cell line-derived neurotrophic factor (GDNF) and transferrin were assessed. The results obtained from the in vivo study showed a duration-dependent significant decrease in body and reproductive organ weights, sperm parameters and serum testosterone concentration. Testicular and epididymal histology also showed duration-dependent degenerative changes. However, all these changes were restored towards control values in the recovery experiment. The viability and deoxyribonucleic acid (DNA) integrity of the treated Sertoli cells showed dose and duration-dependent adverse effects while GDNF and transferrin showed normal genetic expressions. These results suggest that dapsone could induce male reproductive stress by affecting testicular and epididymal structure and function.

Protective action of N-acetylcysteine on sperm quality in cyclophosphamide-induced testicular toxicity in male Wistar rats.

BACKGROUND: Reductions in sperm quality due to free radical formation during cancer chemotherapy are well documented, hence the need for an adjunct antioxidant treatment during chemotherapy. This study was designed to investigate the effects of N-acetylcysteine on sperm quality following cyclophosphamide exposure in male Wistar rats. METHODS: wenty male Wistar rats weighing 150-170g were randomly assigned into 4 groups of five rats each, and were orally administered distilled water (Control), Cyclophosphamide (6mg/kg), N-acetylcysteine (100mg/kg) or Cyclophosphamide + N-acetylcysteine for 21 days. Sperm count, histone-protamine replacement, chromatin integrity, testicular histomorphometry and BAX Protein expression were assessed using standard procedures. The data was presented as mean ± SEM and analyzed using students' t- test. A p<0.05 was considered significant. RESULTS: Sperm counts were significantly reduced (p<0.05) among the cyclophosphamide (69.95±7.78 x106/ml) and cyclophosphamide + N-acetylcysteine (64.78±3.52 x106/ml) treated rats, while it increased significantly (p<0.05) in the N-acetylcysteine (132.20±28.71 x106/ml) treated rats compared to the control animals (115.30±8.70x106/ml). Increased interstitial space distance, degenerated Leydig cells and impaired histone-protamine replacement observed among the cyclophosphamide-treated rats were ameliorated in the cyclophosphamide + N-acetylcysteine-treated rats. Sperm chromatin integrity, which was poor in the cyclophosphamide-treated rats, was considerably improved when compared with the Control and the N-acetylcysteine-treated rats. Bax protein expression was reduced in the cyclophosphamide (20%) and cyclophosphamide+N-acetylcysteine (20%) groups when compared with the Control (50%) and N-acetylcysteine (50%) groups. CONCLUSION: We concluded that N-acetylcysteine might improve sperm histone protamine replacement, which is one of the stage-specific effect of cyclophosphamide toxicity.

Protective effects of methanol extract of Plukenetia conophora seeds and 4H-Pyran-4-One 2,3-Dihydro-3,5-Dihydroxy-6-Methyl on the reproductive function of male Wistar rats treated with cadmium chloride.

OBJECTIVES: Male infertility caused by exposure to heavy metals is a current global issue. Exposure to cadmium chloride (CdCl2) negatively affects the male reproductive system. Many infertile people, especially in developing countries, resort to folkloric treatment. Plukenetia conophora is used in Nigerian folk medicine to promote fertility. This study investigated the effects of Plukenetia conophora (PC) and 4H-Pyran-4-One 2,3-Dihydro-3,5-Dihydroxy-6-Methyl (DDMP) on Wistar rats with cadmium chloride-induced testicular damage. METHODS: Forty-two male Wistar rats (150-190g) were divided into seven groups (n=6) and treated daily for 54 days as follows: Controls (normal saline); CdCl2 (2mg/kg single IP dose); CdCl2 + 200 mg/kg vitamin E; CdCl2 + 100 or 200 mg/kg PC; and CdCl2 + 25 or 50 mg/kg DDMP. The rats were sacrificed 55 days after the start of the study; Samples were collected for analysis. Biochemical parameters malondialdehyde, nitric oxide, antioxidant enzymes, and proton pumps were measured by spectrophotometry. Reproductive hormones were measured using ELISA. Data were analysed using ANOVA and differences in mean values were considered significant at p<0.05. RESULTS: Significant increases in sperm count, motility, and viability were observed in the groups given CdCl2+Vitamin E, CdCl2+PC or CdCl2+DDMP as compared with the CdCl2 group. Malondialdehyde and nitric oxide levels in the groups treated with CdCl2+PC or CdCl2+DDMP decreased significantly when compared with the group given CdCl2. Significant increases were observed in antioxidant enzymes, proton pump, and testosterone in the groups treated with CdCl2+PC or CdCl2+DDMP, respectively. CONCLUSION: Plukenetia conophora alleviated male reproductive toxicity induced by cadmium chloride in Wistar rats. 4H-Pyran-4-One 2,3-Dihydro-3,5-Dihydroxy-6-Methyl present in Plukenetia conophora may be responsible for the ameliorative effects.

Effects of aqueous leaf extract of Tridax procumbens on contractile activity of corpus cavernosum in N-nitro-l-arginine methyl ester-induced hypertensive male rats.

OBJECTIVE: This study investigated the effects of aqueous leaf extract of Tridax procumbens (ALETP) on contractile activity of corpus cavernosum in N-nitro-l-arginine methyl ester (l-NAME)-induced hypertensive male rats. METHODS: Twenty normal, adult male rats (130-150 g) were divided into four groups of five rats each. Group I (control) was given normal saline (0.6 mL/kg) and group II was given l-NAME (40 mg/kg) for 6 weeks. Groups III and IV also received l-NAME (40 mg/kg) for 6 weeks but were further co-treated with 100 and 200 mg/kg of ALETP, respectively, from week 4 to week 6. All treatments were given orally. Strips of corpus cavernosum from each of the four groups were exposed to increasing concentrations of acetylcholine (ACh) and sodium nitroprusside (SNP) (10-9-10-5mol/L) after contraction with phenylephrine (10-7 mol/L) to test for a dose-response effect. Response to potassium and calcium was also measured after cumulatively adding potassium and calcium (10-50 mmol/L) to potassium- and calcium-free organ chamber. Isometric contractions were recorded through an Ugo Basile data capsule acquisition system. RESULTS: Mean arterial blood pressure was significantly reduced in the ALETP co-treated group compared to the control and l-NAME-only groups (P < 0.05). Cavernosa strips from ALETP co-treated rats exhibited significant inhibition of contraction in response to phenylephrine, potassium chloride, and calcium chloride (P < 0.05). Relaxation in response to Ach and SNP was also significantly impaired in cavernosa strips from the l-NAME-only treated group (P < 0.05), while ALETP co-treated groups showed enhanced percentage relaxation. CONCLUSION: ALETP treatment of l-NAME-induced hypertensive rats promotes a relaxant effect on isolated cavernosa strips. ALETP shows potential in correcting erectile dysfunction in hypertension.

Cocos nucifera water improves metabolic functions in offspring of high fat diet fed Wistar rats.

BACKGROUND: Maternal high fat diet has been implicated in the aetiology of metabolic diseases in their offspring. The hypolipidaemic actions of Cocos nucifera water improve metabolic indices of dams consuming a high fat diet during gestation. This study investigated the effects of C. nucifera water on metabolism of offspring of dams exposed to high fat diet during gestation. METHODS: Four groups of pregnant Wistar rat dams (n=6) were treated orally from Gestation Day (GD) 1 to GD 21 as follows: standard rodent feed+10 mL/kg distilled water (Control), standard rodent feed+10 mL/kg C. nucifera water, high fat feed+10 mL/kg distilled water (high fat diet), and high fat feed+10 mL/kg C. nucifera water (high fat diet+C. nucifera water). The feeds were given ad libitum and all dams received standard rodent feed after parturition. Fasting blood glucose was measured in offspring before being euthanized on Postnatal Day (PND) 120. Serum insulin, leptin, lipid profile and liver enzymes were measured. RESULTS: Serum total cholesterol (TC), insulin, alanine transaminase (ALT) and alkaline phosphatase levels were significantly increased (p<0.05) in high fat diet offspring compared with controls. Similar changes were not observed in high fat diet+C. nucifera water offspring. CONCLUSIONS: Results suggest that the adverse effects of maternal high fat diet on offspring's metabolism can be ameliorated by C. nucifera water.

Developing a competency-based medical education curriculum for the core basic medical sciences in an African Medical School.

The College of Medicine of the University of Ibadan recently revised its MBBS and BDS curricula to a competency-based medical education method of instruction. This paper reports the process of revising the methods of instruction and assessment in the core basic medical sciences directed at producing medical and dental graduates with a sound knowledge of the subjects sufficient for medical and dental practice and for future postgraduate efforts in the field or related disciplines. The health needs of the community and views of stakeholders in the Ibadan medical and dental schools were determined, and the "old" curriculum was reviewed. This process was directed at identifying the strengths and weaknesses of the old curricula and the newer competences required for modern-day medical/dental practice. The admission criteria and processes and the learning methods of the students were also studied. At the end of the review, an integrated, system-based, community-oriented, person-centered, and competency-driven curriculum was produced and approved for implementation. Four sets of students have been admitted into the curriculum. There have been challenges to the implementation process, but these have been overcome by continuous faculty development and reorientation programs for the nonteaching staff and students. Two sets of students have crossed over to the clinical school, and the consensus among the clinical teachers is that their knowledge and application of the basic medical sciences are satisfactory. The Ibadan medical and dental schools are implementing their competency-based medical education curricula successfully. The modifications to the teaching and assessment of the core basic medical science subjects have resulted in improved learning and performance at the final examinations.

Implication of caffeine consumption and recovery on the reproductive functions of adult male Wistar rats.

BACKGROUND: This study assessed the impact of caffeine consumption and recovery on reproductive functions and fertility of Wistar rats. METHODS: Thirty-five adult male Wistar rats were divided into seven groups of five rats each. Group A (control) received distilled water (vehicle), while groups B, C, and D were treated orally with 10 mg/kg body weight (BW), 20 mg/kg BW, and 40 mg/kg BW caffeine, respectively, for 30 days. Groups E, F, and G were treated orally with 10 mg/kg BW, 20 mg/kg BW, and 40 mg/kg BW caffeine, respectively, for 30 days and then allowed to recover for another 30 days. RESULTS: Caffeine caused a decrease in body weight, while recovery groups showed appreciable increase in body weight during recovery. Relative weight of seminal vesicle, prostate, and epididymis decreased dose dependently during treatment but increased during recovery. The liver and kidney weight increased during treatment but reduced during recovery. Sperm count was significantly decreased in both treated and recovery groups. Initial decrease in sperm viability and volume was appreciably reversed during recovery period. Serum level of testosterone increased at high doses, while serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) showed significant decrease. Histological sections of testis in treated groups showed mild congestion of the interstitial blood vessel and subcapsular congestion. However, there was no subcapsular congestion in the recovery groups. All rats in both treated and recovery groups had 100% fertilization success from fertility study. CONCLUSIONS: Suggestively, caffeine treatment for 4 weeks could impair body, reproductive organs weight, sperm characteristics, LH/FSH level, and also testicular cyto-architecture. Effects appeared, however, reversible after caffeine withdrawal.

Comparative evaluation of the aphrodisiac efficacy of sildenafil and Carpolobia lutea root extract in male rabbits.

AIMS: In spite of the folkloric use of the root of Carpolobia lutea as a sexual stimulant in man, there has been limited scientific proof of its efficacy. This study compares the efficacy of methanol extract of C. lutea root (MECLR) and sildenafil on the sexual activity of male rabbits. METHODS: 20 adult male rabbits were grouped into four of five rabbits each. Groups 1-4 were treated orally for 28 days with 2 ml/kg 1% Tween-20 (vehicle), 40 mg/kg MECLR, 80 mg/kg MECLR, and 0.5 mg/kg sildenafil citrate (SC), respectively. Sexual activities of males from each group were assessed by cohabiting them with sexually receptive female at estrus on days 0, 1, 3, and 5 using digital camera mounted on mating arena. Serum testosterone and nitric oxide concentration of the corpora cavernosa homogenates were also determined. RESULTS: MECLR caused a dose-dependent significant increase in mount frequency, intromission frequency and ejaculatory latency (EL) while it reduced mount latency, intromission latency and post EL (similar to SC) when compared with the control. MECLR also caused significant increase in nitric oxide concentration in corpora cavernosa but no change in serum testosterone concentration. CONCLUSIONS: Results suggest that MECLR enhances male sexual activity possibly by augmenting nitric oxide concentration. This study thus provides a novel scientific rationale for the use of C. lutea in the management of penile erectile dysfunction and impaired libido.

Effects of Telfairia Occidentalis Seed Oil on Female Reproductive Functions in Wistar Rats.

The effects of T. occidentalis seed oil on some female reproductive indices were investigated in Wistar rats. The study was divided into two phases: (estrous cycle and pregnancy). Animals were grouped into four: group A received distilled water (control), groups B, C and D received 400, 600 and 800 mg/kg bw of T. occidentalis seed oil respectively. The pattern of estrous cycle was determined for three weeks before and during the treatment. Thereafter, each group was sub- divided into two. The sub-group-1 rats were mated with male breeders, the litter size and birth weight of their offsprings was determined. Sub-group-2 rats were sacrificed and histology of organs and serum levels of LH, FSH and estrogen were assayed. There was no significant difference between the pre-treatment and post-treatment estrous cycle length. However, there was a significant decrease in the frequency of diestrus phase during treatment in all the experimental groups when compared with pre-treatment period but there was no significant difference in the diestrus phase when compared with the control group. Serum estrogen concentration was significantly reduced in the group that was treated with 800 mg/kg bw of T. occidentalis seed oil. Histology of the ovary and uterus in the experimental groups were similar to that of the control group. Birth weight of pups was significantly increased in the group treated with 600 mg/kg bw of T. occidentalis seed oil when compared with the control group. The results of this study suggest that T. occidentalis seed oil does not alter estrous cycle in Wistar rats.

Effects of Maternal Dexamethasone Exposure During Lactation on Metabolic Imbalance and Oxidative Stress in the Liver of Male Offsprings of Wistar Rats.

It has been reported in human and animal studies that early exposure to glucocorticoids could retard growth and subsequent development of cardio metabolic diseases. Chronic exposure to glucocorticoids induced oxidative stress. Therefore, the role of oxidative stress in some of the observed metabolic imbalance needs to be elucidated. This study examined the effects of lactational dexamethasone exposure on metabolic imbalance and oxidative stress marker in the liver of male offspring of exposed mother. Twenty lactating dams were divided into 4 groups of 5 animals each. Group 1 was administered 0.02 ml/100gbwt/day normal saline through lactation days 1-21. Group 2, 3, and 4 were administered 100 µg/kgbwt/day dexamethasone for lactation days 1-7, 1-14, and 1-21 respectively. The male offspring were thereafter separated and sacrificed at 12weeks of age for evaluation of lipid profile and oxidative stress marker in the liver. Results from this study indicate that Total Cholesterol (TC), Triglycerides (TAG) and LDL- cholesterol (LDL-C) were significantly  higher in the Dex 1-7, Dex 1-14 and Dex 1-21 groups when compared with the control. HDL-Cholesterol (HDL-C) was significantly reduced in the Dex 1-7, Dex 1-14 and Dex 1-21 groups relative to the control. Basal Fasting Blood Sugar (FBS) was also significantly higher in the Dex 1-14 and Dex 1-21 groups when compared with the control. Liver malondialdehyde was significantly higher in the Dex1-14 and Dex1-21 group compared to the control. However, liver catalase and SOD activity were all significantly lower in Dex 1-7, Dex 1-14 and Dex 1-21 groups relative to control. Liver protein was significantly lower in the Dex1-14 and Dex1-21 treatment groups when compared with the control. Findings from this study suggest that there is possible increase in metabolic imbalance in the offspring of mother exposed to dexamethasone during lactation and these effects may be secondary to increase oxidative stress in the liver.

Nicotine alters serum antioxidant profile in male albino rats.

BACKGROUND: Oxidative stress has repeatedly been implicated as the leading cause of several disease conditions. AIM: This study was designed to investigate the effects of nicotine administration on serum antioxidant levels in male albino rats. MATERIALS AND METHODS: Forty male rats (150-180 g) were divided into five groups and treated orally for 30 days. Group I (control) received 0.2 ml/kg normal saline and Groups II and III received 0.5 and 1.0 mg/kg body weight (BW) of nicotine, respectively for 30 days. The fourth and fifth groups were administered with 0.5 and 1.0 mg/kg BW of nicotine for 30 days, but were left untreated for another 30 days. Serum was assayed for nitric oxide (NO), lipid peroxidation, and antioxidant enzyme. RESULTS: The levels of superoxide dismutase (SOD) and catalase (CAT) were significantly decreased (P < 0.05) in 0.5 and 1.0 mg/kg nicotine treated groups. Glutathione peroxidase (GPx) and glutathione reductase (GR) were significantly decreased (P < 0.05), while NO and malondialdehyde (MDA) were significantly increased (P < 0.05) in 1.0 mg/kg treated group when compared with the control. CONCLUSION: The present study shows that nicotine administration is associated with decreased serum antioxidant and increase lipid peroxidation ameliorated by nicotine withdrawal in male rat.

Nicotine alters male reproductive hormones in male albino rats: The role of cessation.

OBJECTIVES: The use of nicotine through smoking remains a serious health problem. It has been associated with reduced fertility, although the mechanism responsible is still unclear. The present study was designed to investigate whether nicotine-induced infertility is associated with altered male reproductive hormones in male albino rats. MATERIALS AND METHODS: Forty male rats were divided equally into five groups and treated orally for thirty days. Group I, which served as the control received 0.2 ml/kg normal saline, Group II and III received 0.5 mg/kg (low dose) and 1.0 mg/kg (high dose) body weight of nicotine, respectively. The fourth and fifth groups were gavaged with 0.5 mg/kg and 1.0 mg/kg body weight of nicotine but were left untreated for another 30 days. These groups served as the recovery groups. Serum was analyzed for testosterone, luteinizing hormone (LH), follicle stimulating hormones (FSH), and prolactin using radioimmunoassay. RESULTS: Results showed that nicotine administration significantly decreased (P < 0.05) testosterone in the low and high treated groups and FSH in the high dose treated group when compared with the control group. There was a significant increase (P < 0.05) in mean LH and prolactin level in the high dose treated group when compared with the control. However, the values of the recovery groups were comparable with the control. CONCLUSION: The findings in this study suggest that nicotine administration is associated with distorted reproductive hormones in male rats although ameliorated by nicotine cessation. It is plausible that the decreased testosterone level is associated with testicular dysfunction rather than a pituitary disorder.