Isaac Julius Asiedu-Gyekye
University of Ghana
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Featured researches published by Isaac Julius Asiedu-Gyekye.
Journal of Toxicology | 2014
Isaac Julius Asiedu-Gyekye; Samuel Frimpong-Manso; Charles Awortwe; Daniel A. Antwi; Alexander K. Nyarko
Moringa oleifera is a multipurpose plant used in Ghana and most parts of Africa. Its high mineral, protein, and vitamins content has enabled its use as a nutraceutical and panacea for various diseases. This study aimed at measuring the micro- and macroelements content of dried Moringa oleifera leaves using energy dispersive X-ray fluorescence spectroscopic (EDXRF) and assessing its toxicological effect in rats. Acute toxicity (5000 mg/kg) and a subacute toxicity studies of the leaf (40 mg/kg to 1000 mg/kg) extract were conducted in rats. Blood samples were assessed for biochemical and haematological parameters. Results showed significant levels of thirty-five (35) elements (14 macroelements and 21 microelements) in M. oleifera extract. There were no observed overt adverse reactions in the acute and subacute studies. Although there were observed elevations in liver enzymes ALT and ALP (P < 0.001) and lower creatinine levels in the extract treated groups, no adverse histopathological findings were found. Moringa oleifera dried leaf extract may, therefore, be reasonably safe for consumption. However, the consumption of Moringa oleifera leaves should not exceed a maximum of 70 grams per day to prevent cumulative toxicity of these essential elements over long periods.
International Journal of Toxicology | 2014
Isaac Julius Asiedu-Gyekye; Seidu Abdulai Mahmood; Charles Awortwe; Alexander K. Nyarko
Polyhexamethylene guanidine hydrochloride (PHMGH) is used worldwide as an antimicrobial agent with broad spectra of activity and also for treating pool water. This non-GLP preliminary study aims at investigating in a subchronic toxicity study possible effects at supra-optimal doses of this biocide. Both acute and subchronic toxicity studies were conducted. LD50 for PHMGH was estimated to be 600 mg/kg (ie LC50 2 ml of 7.5% solution) when administered as a single dose by gavage via a stomach tube in accordance with the expected route of administration. The acute studies showed that the median lethal dose (LD50) of 600 mg/kg was accompanied by signs of neurotoxicity. Haematological and biochemical parameters of subchronic toxicity studies were non-significant. Subchronic doses of 0.006 mg/kg, 0.012 mg/kg and 0.036 mg/kg were administered. 20% of the animals at a dose of 0.006 mg/kg and 0.036 mg/kg showed mild degrees of hydropic changes in proximal tubules while 10% of animals at all the doses had their liver tissues showing local areas of mild pericentral hepatocytes degeneration. PHMGH did not produce any major organ defect with regard to the kidney, heart, and liver. The LD50 was much higher than the recommended dosage by a factor of about 50,000. The recommended residual concentration is far less than the median lethal dose using rats as test subjects. These results could serve as a basis for investigating the full toxicological profile if it is to be used for the treatment of raw water to make it potable.
Pharmacognosy Research | 2013
Dan K Afriyie; George Awuku Asare; Kwasi Bugyei; Isaac Julius Asiedu-Gyekye; Ben Gyan; Samuel Adjei; Phyllis Addo; Archibald A. Sittie; Alexander K. Nyarko
Background: Croton membranaceus (CM) is used for benign prostate hyperplasia treatment. Objective: Sub-chronic toxicity studies are non-existent and provided the basis for this study. Materials and Methods: 90 days oral administration of a low dose (LD) (30 mg/kg b. wt.), medium dose (MD) (150 mg/kg b. wt.), and high dose (HD) (300 mg/kg b. wt.) CM aqueous root extract to 3 groups (n=6 each) of male Sprague-Dawley rats, alongside a control group, was undertaken. Urinalysis, hepato-renal function tests, lipid profile, cardiac enzymes, and routine hematology tests were performed. Results: Triglyceride levels (C=1.05±0.19, LD=0.64±0.08, MD=0.55±0.04, HD=0.50±0.02 mmol/L) were significantly reduced (P<0.05). Very low density lipoprotein (C=0.48±0.09, LD=0.29±0.04, MD=0.25±0.02, HD=0.23±0.01 mmol/L) decreased significantly (P<0.05). Cardiac enzymes-creatinine kinase (C=568±172, LD=315±79, MD=441±209, HD=286±81 IU/L) decreased markedly (P<0.05) alongside lactate dehydrogenase (C=2675±875, LD=1667±1229, MD=1186±442, HD=855±239 IU/L) (P<0.05). Conclusion: C. membranaceus aqueous root extract is non-toxic but demonstrates anti-atherogenic and anti-ischemic potentials.
Journal of Pharmacy and Bioallied Sciences | 2015
Kennedy Kwami Edem Kukuia; Isaac Julius Asiedu-Gyekye; Eric Woode; Robert Peter Biney; Emmanuel Addae
Context: Kalanchoe sp. have been used since 1921 for central nervous system (CNS) disorders such as psychosis and depression. It is known to possess CNS depressant effects. Aims: To investigate the antidepressant properties of the aqueous leaf extract of Kalanchoe integra. Settings and Design: The study was carried out at the Kwame Nkrumah University of Science and Technology between 6 a.m. and 3 p.m. Materials and Methods: ICR mice were subjected to the forced swimming test (FST) and tail suspension test (TST) after they had received extract (30-300 mg/kg), fluoxetine (3-30 mg/kg), desipramine (3-30 mg/kg) orally, or water (as vehicle). In a separate experiment, mice were pre-treated with reserpine (1 mg/kg), α-methyl paratyrosine (AMPT; 400 mg/kg), both reserpine (1 mg/kg) and AMPT (200 mg/kg) concomitantly, or p-chlorophenylalanine (pCPA; 200 mg/kg) to ascertain the role of the noradrenergic and serotoninergic systems in the mode of action of the extract. Statistical analysis used: Means were analyzed by analysis of variance (ANOVA) followed by Newman-Keuls’ post hoc test. P < 0.05 was considered significant. Results: In both FST and TST, the extract induced a decline in immobility, indicative of antidepressant-like effect. This diminution in immobility was reversed by pCPA, but not by reserpine and/or AMPT. The extract increased the swimming and climbing scores in the FST, suggestive of possible interaction with serotoninergic and noradrenergic systems. In the TST, the extract produced increases in both curling and swinging scores, suggestive of opioidergic monoaminergic activity, respectively. Conclusions: The present study has demonstrated the antidepressant potential of the aqueous leaf extract of K. integra is mediated possibly by a complex interplay between serotoninergic, opioidergic, and noradrenergic systems.
Andrologia | 2014
Dan K Afriyie; George Awuku Asare; Kwasi Bugyei; Isaac Julius Asiedu-Gyekye; R. Tackie; Samuel Adjei
Croton membranaceus Müll.Arg. (Euphorbiaceae) is used for benign prostate hyperplasia (BPH) treatment. The study aimed at investigating organs that the aqueous root extracts of C. membranaceus (CMARE) target, which is absent in literature. Twenty‐four male Sprague‐Dawley rats (100–140 g) were randomly divided into 4 groups. Group 1, the control group received distilled water. Groups 2, 3 and 4 received 30, 150 and 300 mg kg−1 b.wt CMARE respectively (oral gavage). Rats fed 90 days the standard chow diet ad libitum. Upon sacrifice, major organs were histologically examined and serum prostate‐specific antigen (PSA) biochemically determined. Only the prostate was abnormal. Histologically, H&E staining revealed thickness and infoldings of the epithelial cells shrinking with increasing dose. The 30 mg kg−1 group showed low columnar or flattened epithelium cells, whereas the columnar epithelium infoldings of the 150 mg kg−1 b.wt and 300 mg kg−1 b.wt groups were virtually nonexistent. The acini of the control, 30 mg kg−1 b.wt group and the 150 mg kg−1 b.wt groups showed clear pinkish secretion. However, secretion of the high‐dose group appeared light pink in colour and the stroma cells appeared much darker than all the treated and control group. C. membranaceus targets the prostate with significant PSA reduction (P < 0.01).
International Journal of Immunopathology and Pharmacology | 2014
C. Awortwe; Isaac Julius Asiedu-Gyekye; E. Nkansah; S. Adjei
Unsweetened natural cocoa powder is enriched with nutraceutical abundance of anti-asthmatic compounds theobromine and theophylline. Cocoa powder, which is prepared after removal of the cocoa butter, contains about 1.9% theobromine and 0.21% caffeine. Anecdotal reports indicate that regular consumption of unsweetened natural cocoa powder (UNCP), a common practice in Ghana, West Africa, has the potential to reduce the tendency of asthmatic episodes. In the present paper we studied the effect of regular ingestion of aqueous extract of UNCP on hematological and histopathological changes that occur in ovalbumin (OVA)-sensitized guinea pigs. OVA-sensitized guinea pigs were challenged with aerosolized OVA 1 hour after ingestion of 300 mg/kg (low dose) or 600 mg/kg (high dose) of UNCP for 35 consecutive days. Histopathological and haematological changes in the OVA-sensitized guinea pigs were evaluated. Both negative and positive controls with distilled water and prednisolone, respectively, were used. OVA-sensitized guinea pigs demonstrated concentration-independent reduction in immune response to aerosolized OVA. There were no histo-architectural changes in the bronchiolar smooth muscles of the treated groups. Unsweetened natural cocoa powder has potential anti-asthmatic properties when administered orally at the doses tested.
Pharmaceutical Biology | 2013
George Awuku Asare; Kwasi Bugyei; Irene Fiawoyi; Isaac Julius Asiedu-Gyekye; Ben Gyan; Samuel Adjei; Phyllis Addo; Lydia Otu-Nyarko; Alexander K. Nyarko
Abstract Context: Phyllanthus niruri L. (Euphorbiaceae), a medicinal plant traditionally known for dissolving kidney stones, is used prophylactically as an antimalarial agent. Objective: The study was undertaken to determine its effect on some male hormones and other toxicological properties due to paucity of its data despite its wide use. Material and methods: Male Sprague–Dawley rats (100–140 g) were used. Group 1 [control group (C), n = 6] received water. Group 2 [low-dose test group (LD), n = 6] received 50 mg/kg body weight (b.wt.) aqueous leaf extract orally. Group 3 [high-dose test group (HD), n = 6] received 500 mg/kg b.wt. extract for 90 days. Upon sacrifice, among other organs the testes were harvested. Blood samples drawn were used for biochemical (including progesterone, estrogen and testosterone), cytotoxicity and hematological assays. Results: C, LD and HD estrogen values were 192 ± 25, 385 ± 122 and 962 ± 357 pg/ml, respectively. In the same order, progesterone values were 96 ± 24, 155 ± 45 and 320 ± 80 pg/ml, respectively. Testosterone levels were 5210 ± 1090, 4710 ± 220 and 4500 ± 580 pg/ml, respectively. Significant differences were observed in the estrogen and progesterone levels (p = 0.001). Degenerative changes were observed histologically. Cytotoxicity at 50% (CC50) was 10.0 µg/ml. Discussion and conclusion: This antimalarial plant is mildly cytotoxic with male antifertility properties.
Journal of Intercultural Ethnopharmacology | 2016
Isaac Julius Asiedu-Gyekye; Charles Antwi-Boasiako; Seth Oppong; Stella Arthur; Joseph Edusei Sarkodie
Background: Unsweetened natural cocoa powder (UNCP), prepared after removal of the cocoa butter, is a common beverage in Ghana. It possesses antimalarial prophylactic property and has a beneficial effect on blood components. Aim: The aim of this study was to determine whether regular dietary supplement of UNCP mitigates high-dose (HD) artemether-lumefantrine (A-L)-induced hematological disorders and to determine the effect on nitric oxide (NO) levels. Materials and Methods: Adult male guinea pigs (300 g - 350 g) were randomly divided into 5 groups of 6 guinea pigs each. Among the 5 groups, 3 groups were treated with UNCP (300, 900, and 1500 mg/kg body weight) for 14 days. A-L (75 mg/kg) was administered from the 12th to 14th day. One of the remaining 2 groups received distilled water only, i.e., vehicle control group (VCG) while the other received 75 mg/kg A-L only, i.e., negative control group (NCG). Blood samples from all groups were obtained by cardiac puncture (day 15) followed by hematological and NO analysis. Results: A-L reduced white blood cells (WBC) by 31.87%, lymphocyte count by 45.99%, hemoglobin by 11.72%, hematocrit by 18.56%, and platelet count by 33.08% in the NCG. Administration of various doses of UNCP increased WBC and lymphocyte count (P > 0.05) compared to the NCG. UNCP and A-L combination caused an increase in NO levels when compared to the VCG. Conclusion: Regular consumption of UNCP by guinea pigs increases plasma NO and restores some hematological disorders induced by a 3-day HD A-L administration.
Interdisciplinary Toxicology | 2015
Isaac Julius Asiedu-Gyekye; Abdulai Seidu Mahmood; Charles Awortwe; Alexander K. Nyarko
Abstract Polyhexamethylene biguanide (PHMB) is an antiseptic with antiviral and antibacterial properties used in a variety of products including wound care dressings, contact lens cleaning solutions, perioperative cleansing products, and swimming pool cleaners. There are regulatory concerns with regard to its safety in humans for water treatment. We decided to assess the safety of this chemical in Sprague-Dawley rats. PHMB was administered in a single dose by gavage via a stomach tube as per the manufacturer’s instruction within a dose range of 2 mg/kg to 40 mg/kg. Subchronic toxicity studies were also conducted at doses of 2 mg/kg, 8 mg/kg and 32 mg/kg body weight and hematological, biochemical and histopathological findings of the major organs were assessed. Administration of a dose of 25.6 mg/kg, i.e. 1.6 mL of 0.4% PHMB solution (equivalent to 6.4×103 mg/L of 0.1% solution) resulted in 50% mortality. Histopathological analysis in the acute toxicity studies showed that no histopathological lesions were observed in the heart and kidney samples but 30% of the animals had mild hydropic changes in zone 1 of their liver samples, while at a dosage of 32 mg/kg in the subchronic toxicity studies, 50% of the animals showed either mild hepatocyte cytolysis with or without lymphocyte infiltration and feathery degeneration. Lymphocyte infiltration was, for the first time, observed in one heart sample, whereas one kidney sample showed mild tubular damage. The acute studies showed that the median lethal dose (LD50) is 25.6 mg/kg (LC50 of 1.6 mL of 0.4% PHMB. Subchronic toxicological studies also revealed few deleterious effects on the internal organs examined, as seen from the results of the biochemical parameters evaluated. These results have implications for the use of PHMB to make water potable.
Journal of Ethnopharmacology | 2014
Isaac Julius Asiedu-Gyekye; Daniel A. Antwi; Charles Awortwe; Benoit N'Guessan; Alexander K. Nyarko
ETHNOPHARMACOLOGICAL RELEVANCE Kalanchoe intergra (Ki) leaf extract is an orally administered multipurpose plant medicine in Ghana and other parts of the world for the treatment of ulcers, pain and adenoma of the prostate gland. There is paucity of information concerning its short-term usage. The present study is aimed at conducting histopathological and biochemical studies in a 14-day sub-acute toxicity studies using female Sprague-Dawley rats. MATERIALS AND METHODS Crude extract of Ki leaves was prepared and freeze-dried. A 14-day sub-acute toxicity studies was conducted using 2 week old nulliparous and non-pregnant female Sprague-Dawley rats (120-150g). Reconstituted Ki was administered at a dosage of 900mgkg(-1) (high dose), 300mgkg(-1) with a control group receiving an equivalent volume of distilled water (as vehicle) by gastric lavage. Histopathological studies of major organs and blood chemistry analysis were performed on blood obtained via cardiac puncture into EDTA tubes after euthanisation. RESULTS There was a significant decrease in urea (p<0.016) and creatinine levels (p<0.001) in both the high and low dose groups. There was an increase in ALP levels (P=0.01) in both the high and low dose groups. ALT and AST rather decreased significantly in both the high and low dose groups (p<0.0001). Histopathological results did not show any abnormalities in all the H&E stained paraffin sections. Thus the photomicrographs of the liver, kidney and heart were within histopathological limits. CONCLUSION Ki leaf extract is non-toxic when administered by the oral route over a time period of 14 days at the above doses.