Effects of Combined Garcinia kola and Kigelia africana on Insulin and Paraoxonase 1 (PON1) Levels in Type 2 Diabetic Rats.

BACKGROUND: Individual extracts of Garcinia kola and Kigelia africana have been shown to have therapeutic effects against a variety of variables linked to the development of diabetes mellitus. However, there is still a lack of information about the combined effects of these extracts on Insulin and Paraoxonase 1 (PON-1) in Streptozotocin-Nicotinamide-induced type-2 diabetic Wistar rats. METHODS: Forty-two young male rats (180-200g) were randomly divided into six groups (n = 7/group). Diabetes was intraperitoneally induced with 110 mg/kg of nicotinamide constituted in distilled water and fifteen minutes later with 65 mg/kg of streptozocin freshly prepared in 0.1M citrate buffer (pH of 4.5) and treated for six weeks as follows: the control rats received either 0.9% normal saline (NS) or 250 mg/kg extract by gavage. The remaining animals were diabetes induced and subsequently treated with either NS, graded doses of the extract (250 mg/kg and 500 mg/kg), or 5 mg/kg Glibenclamide + 100mg/kg Metformin. Gas chromatography-mass spectrometry (GCMS) of the combined extracts was also analyzed to identify the bioactive compounds present in it. Insulin, PON-1 levels, lipid profiles, and atherogenic index were assessed. RESULTS: Our findings show that Insulin and PON-1 levels in the plasma of diabetic rats treated with the combined extracts were significantly increased when compared to the control rats. Moreover, the GCMS of the extract shows the presence of both monounsaturated (oleic acid) and polyunsaturated (linoleic acid) fatty acids. CONCLUSION: The current findings suggest that the extract may help improve glucose homeostasis and prevent atherosclerosis through the established mechanism of the identified bioactive compounds.

A review on garcinia kola heckel: traditional uses, phytochemistry, pharmacological activities, and toxicology.

PURPOSE: Garcinia kola is a medicinal plant commonly known as bitter kola. It is utilised in ethnomedicine for the treatment of diarrhoea, bronchitis, bacterial infection, cough, hepatitis, gonorrhoea, laryngitis, food poison, liver and gastric diseases. OBJECTIVE: This study reviewed the phytochemistry, pharmacological activities, and ethnomedicinal potentials of G. kola. MATERIALS AND METHODS: An extensive review was performed using electronic literature collated from ScienceDirect, Springer, Wiley, and PubMed databases. RESULTS: Phytochemical analysis revealed the isolation of several chemical compounds including 9-octadecenoic acid, linoleic acid, 14-methylpentadecanoic acid, 1-butanol, hexadecanamide, I-4',II-4',I-5,II-5,I-7,II-7-hexahydroxy-I-3,II-8-biflavanone, lanost-7-en-3-one, kolaflavanone (8E)-4-geranyl-3,5-dihydroxybenzophenone, glutinol, Garcinia biflavonoid (GB-2a-II-4'-OMe), 9,19-cyclolanost-24-en-3-ol, 24-methylene, tirucallol, lupeol, ß-amyrin, obtusifoliol and Kolaviron. Diverse pharmacological in-vivo and in vitro investigations revealed that G. kola has anti-inflammatory, antimalarial, hepatoprotective, cardioprotective, anti-asthmatic, neuroprotective, antioxidant, and antidiabetic activities. CONCLUSION: The present study revealed that G. kola has preventive and therapeutic potentials against various diseases in both in vivo and in vitro studies and therefore can be utilised as a raw material in the pharmaceutical industries for the development of therapeutic products. However, there is a need for clinical trial experiments to validate and provide accurate and substantial information on the required safe dosage and efficacy for the treatment of several diseases.

Garcinia kola and garcinoic acid suppress SARS-CoV-2 spike glycoprotein S1-induced hyper-inflammation in human PBMCs through inhibition of NF-κB activation.

Symptoms and complications associated with severe SARS-CoV-2 infection such as acute respiratory distress syndrome (ARDS) and organ damage have been linked to SARS-CoV-2 spike protein S1-induced increased production of pro-inflammatory cytokines by immune cells. In this study, the effects of an extract of Garcinia kola seeds and garcinoic acid were investigated in SARS-CoV-2 spike protein S1-stimulated human PBMCs. Results of ELISA experiments revealed that Garcinia kola extract (6.25, 12.5, and 25 µg/ml) and garcinoic acid (1.25, 2.5, and 5 µM) significantly reduced SARS-CoV-2 spike protein S1-induced secretion of TNFα, IL-6, IL-1ß, and IL-8 in PBMCs. In-cell western assays showed that pre-treatment with Garcinia kola extract and garcinoic acid reduced expressions of both phospho-p65 and phospho-IκBα proteins, as well as NF-κB DNA binding capacity and NF-κB-driven luciferase expression following stimulation of PBMCs with spike protein S1. Furthermore, pre-treatment of PBMCs with Garcinia kola extract prior to stimulation with SARS-CoV-2 spike protein S1 resulted in reduced damage to adjacent A549 lung epithelial cells. These results suggest that the seed of Garcinia kola and garcinoic acid are natural products which may possess pharmacological/therapeutic benefits in reducing cytokine storm in severe SARS-CoV-2 and other coronavirus infections.

Garcinia kola (Heckel) and Alchornea cordifolia (Schumach. & Thonn.) Müll. Arg. from Cameroon possess potential antisalmonellal and antioxidant properties.

Drug resistant Salmonella species and shortcomings related to current drugs stress the urgent need to search for new antimicrobial agents to control salmonellosis. This study investigated the antisalmonellal and antioxidant potentials of methanolic and hydro-ethanolic extracts of Garcinia kola and Alchornea cordifolia as potential sources of drugs to control Salmonella species and to reduce related oxidative stress. The antisalmonellal activity was assessed using the broth microdilution, membrane destabilization and time-kill kinetic assays. While, the DPPH, ABTS and FRAP assays were used for the determination of the antioxidant activities. The minimum inhibitory concentrations ranged from 125 to 1000 µg/mL, with the methanolic root extract of G. kola being the most active. The time kill kinetic assay revealed a concentration-dependent bacteriostatic activity for promising extracts. Potent extracts from G. kola showed the ability to destabilize S. typhi outer membrane, with the methanolic root extract presenting the highest activity; two-fold higher than those of polymyxin B tested as reference. In addition, this methanolic root extract of G. kola also provoked nucleotide leakage in a concentration-dependent manner. From the antioxidant assays, the hydro-ethanolic extract from the stem bark of A. cordifolia presented significant activities comparable to that of Vitamin C. The methanolic root extract of G. kola also presented appreciable antioxidant activities, though less than that of A. cordifolia. Overall, the phytochemical screening of active extracts revealed the presence of anthocyanins, flavonoids, glycosides, phenols, tannins, triterpenoids and steroids. These results provide evidence of the antibacterial potential of G. kola and offer great perspectives in a possible standardisation of an antisalmonellal phytomedicine.

Gakolanone: a new benzophenone derivative from Garcinia kola Heckel stem-bark.

Gakolanone (3',5'-digeranyl-2',4',6',3-tetrahydroxybenzophenone; 1), a novel benzophenone derivative was isolated from the hexane extract of Garcinia kola Heckel stem-bark along with three known 3-8'' linked biflavonoids: 3'',4',4''',5,5'',7,7''-heptahydroxy-3,8''-biflavanone (2); 3'',4',5,5'',5''',7,7''-heptahydroxy-4-methoxy-3,8''-biflavanone (3) and 4',4''',5,5'',7,7''-hexahydroxy-3,8''-biflavanone (4) from the ethanol extract. The compounds were characterized primarily using 1 D and 2 D nuclear magnetic resonance spectroscopy and mass spectrometry and by comparing with literature. The compounds were subjected to in-vitro alpha-amylase enzyme inhibitory assay using DNSA (3,5-dinitrosalicylic acid) reagent with acarbose used as the standard drug. All the compounds were found to show alpha-amylase inhibitory activities with IC50 of 21.4 ± 1.5, 9.9 ± 0.2, 15.3 ± 2.3, 12.9 ± 2.3 µg/mL respectively. All the compounds exhibited better alpha-amylase inhibitory activities than the standard drug, acarbose (IC50= 38.1 ± 8.3 µg/mL).

Antioxidative, antimitotic, and DNA-damaging activities of Garcinia kola stem bark, Uvaria chamae root, and Olax subscorpioidea root used in the ethnotherapy of cancers.

Garcinia kola (GK) stem bark, Uvaria chamae (UC) root, and Olax subscorpioidea (OS) root are components of various indigenous/traditional anticancer regimens. It is, therefore, possible that they might combat oxidative stress and impair cellular proliferation linked to carcinogenesis. In this study, we investigated the antioxidative, mito-depressive, and DNA-damaging activities of the three plant extracts in order to provide further mechanistic insights into their potential anticancer roles in documented cancer remedies that include them. Antioxidative properties were investigated in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging assays and an animal model of drug (cisplatin)-induced oxidative stress. The Allium cepa assay and the single cell gel electrophoresis (SCGE) assay were used to assess mito-depressive and DNA-damaging activities. GK and OS showed significantly higher antioxidant activities in the DPPH assay than ascorbic acid; OS had the lowest IC50 of the three plants in the NO assay, comparable to that of ascorbic acid. Pretreatment with the extracts produced an ameliorative and protective effect against the cisplatin-induced oxidative stress as shown by inhibition of lipid peroxidation and improved or restored reduced glutathione and superoxide dismutase levels. In the Allium test, the three extracts produced significant decreases in root growth and also significant cytotoxicity as evidenced by decreased mitotic index. Each of the extracts also showed significantly increased tail DNA (%) in the SCGE assay, indicating the significant DNA-damaging effect. Taken together, this study demonstrates the possible chemopreventive and chemotherapeutic potentials of the three study extracts, which may explain the roles of their source plants in traditional remedies in the therapy of cancers.

Identification and control of specific aflatoxin-producing fungi in stored maize seeds in awka using azadirachta indica (neem) and garcinia kola seeds.

Four fungal isolates were identified in this study of which three were Aspergillus species with Aspergillus flavus having the highest frequency followed by A. parasiticus. The result of high frequency of Aspergillus flavus and Aspergillus parasiticus in the Zea mays sample revealed production of aflatoxins. Maize sample in Awka was found to contain aflatoxin B1 (9.60ppb) and B2 (13.3ppb). Inhibition of A. flavus and A. parasiticus with Azadirachta indica and Garcinia kola seed extracts showed that the test plant extracts were effective for reducing mycelial growth on the test organism. Methanolic extract of G. kola showed antifungal inhibitory activity on the test organisms and the highest at 10% concentration. With ethanol extracts of G. kola, the antifungal activity was effective i.e. for inhibition of A. flavus and A. parasiticus, with A. parasiticus having the higher percentage inhibition at 10%. Inhibiting growth of Aspergillus flavus and Aspergillus parasiticus using methanolic and ethanolic extracts of neem seeds was effective in the inhibition of the test organism at 10%. The methanolic and ethanolic extracts of combined Garcinia kola and neem seeds revealed effective inhibition of A. flavus and A. parasiticus with ethanolic extracts of the combined test plants exerting the highest inhibition against A. flavus (80.43±3.62). The extracts from this plant show the ability to suppress growth of toxigenic A. flavus and A. parasiticus. Phytochemical analysis showed that the methanolic and ethanolic extracts of G. kola and neem seeds showed the presence of secondary metabolites and this may be a reason for the inhibitory activity on A. flavus and A. parasiticus. Results from this study will be important in planning a management strategy against aflatoxin-producing fungi and other fungi associated with spoilage of stored food products.

GC-Recomposition-Olfactometry (GC-R) and multivariate study of three terpenoid compounds in the aroma profile of Angostura bitters.

Foods and beverage aroma results from multicomponent mixtures of volatile compounds present in the food that interact with olfactory receptors and produce a perceptual response in the brain. However, the perceptual interactions that occur when complex odor mixtures are combined are not well understood. Here we used Gas chromatography-Recomposition-Olfactometry (GC-R) to better understand the role that individual compounds have on the perceived sensory aroma of bitters. Bitters are the concentrated alcoholic extract of flavorful plant materials with a wide range of complex sensory and chemical aroma profiles that have not been extensively studied. Previously, we demonstrated that Angostura bitters are characterized by complex aroma attributes described as cola, ginger, orange peel, and black pepper and that the volatile composition of Angostura bitters is predominantly composed of terpenoids. Using GC-R to create in-instrument mixtures of the Angostura headspace extracts, the sensory attributes of Angostura extracts with linalool, α-terpinyl-acetate and caryophyllene omitted were evaluated. The omission experiments demonstrated direct and indirect effects of the individual compounds on the aroma attributes of Angostura bitters, through masking, additive, and synergistic interactions. Caryophyllene in particular, which was present in the headspace extracts at concentration only slightly above sensory threshold levels, had a large and unexpected impact on the sensory properties of the mixtures and may be most responsible for the aromas associated with the whole sample. The GC-R and statistical approaches used here provided valuable tools to reveal relationships among individual compounds and aroma attributes of foods that have not been currently theorized using existing analytical approaches.

The vitamin E derivative garcinoic acid from Garcinia kola nut seeds attenuates the inflammatory response.

The plant Garcinia kola is used in African ethno-medicine to treat various oxidation- and inflammation-related diseases but its bioactive compounds are not well characterized. Garcinoic acid (GA) is one of the few phytochemicals that have been isolated from Garcinia kola. We investigated the anti-inflammatory potential of the methanol extract of Garcinia kola seeds (NE) and purified GA, as a major phytochemical in these seeds, in lipopolysaccharide (LPS)-activated mouse RAW264.7 macrophages and its anti-atherosclerotic potential in high fat diet fed ApoE-/- mice. This study outlines an optimized procedure for the extraction and purification of GA from Garcinia kola seeds with an increased yield and a purity of >99%. We found that LPS-induced upregulation of iNos and Cox2 expression, and the formation of the respective signaling molecules nitric oxide and prostanoids, were significantly diminished by both the NE and GA. In addition, GA treatment in mice decreased intra-plaque inflammation by attenuating nitrotyrosinylation. Further, modulation of lymphocyte sub-populations in blood and spleen have been detected, showing immune regulative properties of GA. Our study provides molecular insights into the anti-inflammatory activities of Garcinia kola and reveals GA as promising natural lead for the development of multi-target drugs to treat inflammation-driven diseases.

Protective Effect of Kolaviron on Cyclophosphamide-Induced Cardiac Toxicity in Rats.

BACKGROUND: Cyclophosphamide (CP) is a nitrogen mustard alkylating drug used for the treatment of chronic and acute malignant lymphomas, myeloma, leukemia, neuroblastoma, adenocarcinoma, retinoblastoma, breast carcinoma, and immunosuppressive therapy. Despite its vast therapeutic uses, it is known to cause severe cardiac toxicity. Kolaviron (KV), a Garcinia kola seed extract containing a mixture of flavonoids, is reputed for its antioxidant and membrane stabilizing properties. OBJECTIVE: This study investigated the protective effect of KV on CP-induced cardiotoxicity in rats. METHODS: Thirty rats were used, and they were divided into 6 groups of 5 rats each. Group I received 2 mL/kg propylene glycol orally for 14 days; group II received CP (50 mg/kg/d, intraperitoneally [i.p.]) for 3 days; groups III and IV received 200 and 400 mg/kg/d KV, respectively, orally for 14 days and groups V and VI were pretreated with 200 and 400 mg/kg/d KV, respectively, orally for 14 days followed by CP (50 mg/kg/d, i.p.) for 3 days. RESULTS: CP treatment resulted in a significantly lower food consumption and body weight in rats. The lactate dehydrogenase and creatine kinase enzymes in cardiac tissues of rats treated with CP were significantly higher. In cardiac tissues, 3-day doses of CP resulted in significantly higher heart weight, cardiac troponin I, myeloperoxidase, malondialdehyde, hydrogen peroxide and lower superoxide dismutase, catalase, glutathione peroxidase activities, and reduced glutathione levels. Histological examination of cardiac tissues showed sign of necrosis of myocardium after CP treatment. However, administration of KV at 200 and 400 mg/kg for 14 days prior to CP treatment, increase food consumption, body weight, and attenuates the biochemical and histological changes induced by CP. CONCLUSIONS: These results revealed that KV attenuates CP-induced cardiotoxicity by inhibiting oxidative stress and preserving the activity of antioxidant enzymes.

Kolaviron and Garcinia kola Seed Extract Protect Against Ischaemia/Reperfusion Injury on Isolated Rat Heart.

BACKGROUND: The incidence of cardiovascular diseases and its associated complications have increased greatly in the past three decades. The purpose of this study was to evaluate the acute cardioprotective effects of Garcinia kola (GK) seed extract and Kolaviron (KV) and determine mechanisms of action involving RISK signalling pathways. METHODS: Male Wistar rats were used in this study. Hearts were excised and mounted on the Langendorff perfusion system. The control, group 1 was perfused with dimethyl sulfoxide (DMSO), group II with KV and group III with GK respectively. Western blot analyses were performed on frozen heart tissues. RESULTS: Isolated rat hearts perfused with KV and GK attenuated apoptotic pathways with significant reduction in p38 MAPK protein phosphorylation, as well as reduction in total caspase 3, cleaved caspase 3 (Asp 175) and PARP cleavage. KV and GK also down-regulated p-JNK1 (Tyr 185) and p-JNK 2 (Thr 183) protein expression at the 10 min reperfusion time ponit. Cardioprotection was achieved in part, by enhancement of the reperfusion injury signalling kinase (RISK) pathway; as evidenced by significant increases in protein expresion of Akt/PKB and p-Akt/PKB (Ser 473) in KV and GK respectively. CONCLUSIONS: KV and GK supplementation led to significant increases in the expressions of survival proteins. It is noteworthy that both KV and GK supplementation offered cardioprotection in ischaemic/reperfusion injury rat heart model. In all, GK showed better cardioprotective effect that KV.

Kolaviron and Garcinia kola attenuate doxorubicin-induced cardiotoxicity in Wistar rats.

Background The Garcinia kola seeds have been reported for its antibacterial, antioxidant, antidiabetic and also for its chemoprevention property. The use of doxorubicin as an anticancer drug has been accompanied with avalanche of side effects including cardiotoxicity. The aim of this study was to investigate the cardioprotective effect of Kolaviron and Garcinia kola and their mechanisms of action. Methods Sixty male rats (Wistar strain) were used in this study. They were divided into 6 groups (A-F) each containing 10 animals. Group A was the control. Rats in Groups B, C, D, E and F were treated with doxorubicin at the dosage of 15 mg/kg body weight i.p. Prior to this treatment, rats in groups C, D, E and F were pre-treated orally with Kolaviron at the dosage of 100 mg/kg and 200 mg/kg, and Garcinia kola 100 mg/kg and 200 mg/kg for 7 days, respectively. Results The results show that doxorubicin caused a significant increase in heart rate and prolonged QT, reduced antioxidant status, increased oxidative stress, inflammation and markers of cardiac damage which were reversed by pre-treatment with Kolaviron and Garcinia kola. Conclusions Overall, pre-treatment with Kolaviron or Garcinia kola caused reversal of cardiac damage, ECG alteration and oxidative stress by increasing the activity of antioxidant enzymes and reducing the markers of inflammation on doxorubicin-induced cardiotoxicity.

Garcinia kola aqueous suspension prevents cerebellar neurodegeneration in long-term diabetic rat - a type 1 diabetes mellitus model.

ETHNOPHARMACOLOGICAL RELEVANCE: The development of compounds able to improve metabolic syndrome and mitigate complications caused by inappropriate glycemic control in type 1 diabetes mellitus is challenging. The medicinal plant with established hypoglycemic properties Garcinia kola Heckel might have the potential to mitigate diabetes mellitus metabolic syndrome and complications. AIM OF THE STUDY: We have investigated the neuroprotective properties of a suspension of G. kola seeds in long-term type 1 diabetes mellitus rat model. MATERIALS AND METHODS: Wistar rats, made diabetic by single injection of streptozotocin were monitored for 8 months. Then, they were administered with distilled water or G. kola oral aqueous suspension daily for 30 days. Body weight and glycemia were determined before and after treatment. After sacrifice, cerebella were dissected out and processed for stereological quantification of Purkinje cells. Histopathological and immunohistochemical analyses of markers of neuroinflammation and neurodegeneration were performed. RESULTS: Purkinje cell counts were significantly increased, and histopathological signs of apoptosis and neuroinflammation decreased, in diabetic animals treated with G. kola compared to diabetic rats given distilled water. Glycemia was also markedly improved and body weight restored to non-diabetic control values, following G. kola treatment. CONCLUSIONS: These results suggest that G. kola treatment improved the general condition of long-term diabetic rats and protected Purkinje cells partly by improving the systemic glycemia and mitigating neuroinflammation.

Three indigenous plants used in anti-cancer remedies, Garcinia kola Heckel (stem bark), Uvaria chamae P. Beauv. (root) and Olax subscorpioidea Oliv. (root) show analgesic and anti-inflammatory activities in animal models.

ETHNOPHARMACOLOGICAL RELEVANCE: Phytochemicals with anti-oxidative and anti-inflammatory properties are known to inhibit tumour initiation, promotion and progression. Hence, there is an increasingly-convincing rationale for employing remedies containing those phytochemicals in the treatment of cancers and also as analgesic and anti-inflammatory adjuvants in therapy. The plants Garcinia kola Heckel (Clusiaceae), stem bark; Uvaria chamae P. Beauv. (Annonaceae), root; and Olax subscorpioidea Oliv. (Olacaceae), root, have been documented to be part of various indigenous anti-cancer regimens. AIM OF THE STUDY: To determine if the three plants exhibit significant anti-oxidative and anti-inflammatory properties. MATERIALS AND METHODS: Using established models, the analgesic and anti-inflammatory activities of the three plants were investigated. RESULTS: Pre-treatment with the plant extracts at 100, 200 and 400mg/kg produced inhibition of writhes; G. kola and U. chamae showed no significant effect on formalin-induced pain, but O. subscorpioidea produced inhibition in both phases of the formalin test. Similarly, while G. kola and U. chamae did not produce any significant inhibitory effect in the xylene-induced ear oedema model, the oedema was significantly reduced by O. subscorpioidea pre-treatment. However, all the three plants significantly inhibited the time-dependent increase in paw circumference in the carrageenan- and formaldehyde-induced rat paw oedema tests, with peak effects observed at 400mg/kg, 6h after the induction of oedema, comparable in some cases to the effects of two standard drugs, the non-steroidal anti-inflammatory drug diclofenac and the anti-inflammatory antibiotic doxycycline. CONCLUSION: We conclude that the three plant extracts possess analgesic and anti-inflammatory properties, thus providing a scientific rationale for their inclusion in some traditional anti-cancer regimens.

Fingerprinting and validation of a LC-DAD method for the analysis of biflavanones in Garcinia kola-based antimalarial improved traditional medicines.

African populations use traditional medicines in their initial attempt to treat a range of diseases. Nevertheless, accurate knowledge of the composition of these drugs remains a challenge in terms of ensuring the health of population and in order to advance towards improved traditional medicines (ITMs). In this paper chromatographic methods were developed for qualitative and quantitative analyses of a per os antimalarial ITM containing Garcinia kola. The identified analytical markers were used to establish TLC and HPLC fingerprints. G. kola seeds were analysed by HPLC to confirm the identity of the extract used by the Congolese manufacturer in the ITM. The main compounds (GB1, GB2, GB-1a and Kolaflavanone) were isolated by preparative TLC and identified by UPLC-MS and NMR. For the quantification of the major compound GB1, a simple and rapid experimental design was applied to develop an LC method, and then its validation was demonstrated using the total error strategy with the accuracy profile as a decision tool. The accurate results were observed within 0.14-0.45mg/mL range of GB1 expressed as naringenin. The extracts used in several batches of the analysed oral solutions contained GB1 (expressed as naringenin) within 2.04-2.43%. Both the fingerprints and the validated LC-DAD were found suitable for the quality control of G. kola-based raw material and finished products, respectively.

Biflavonoid fraction from Garcinia kola seed ameliorates hormonal imbalance and testicular oxidative damage by anti-tuberculosis drugs in Wistar rats.

BACKGROUND: Tuberculosis (TB) is a global health problem. The effects of anti-TB drugs on male reproductive system have not been properly evaluated. We investigated the effects of anti-TB drugs on testicular antioxidant indices, sperm characteristics and hormonal levels in rats, and the protective role of kolaviron (KV), a biflavonoid from Garcinia kola seed. METHODS: Twenty-eight male Wistar rats were assigned into four groups and orally treated with corn oil (control), anti-TB drugs [4-Tabs=isoniazid (5 mg/kg), rifampicin (10 mg/kg), pyrazinamide (15 mg/kg) and ethambutol (15 mg/kg) in combination], anti-TB drugs +KV and KV alone (200 mg/kg). Anti-TB drugs and KV were given three times per week for 8 weeks. In vitro, reducing power, inhibition of lipid peroxidation (LPO), diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging effects of KV were examined. RESULTS: KV at 10, 20, 50 and 100 µg/mL showed strong reducing potential and effectively scavenged DPPH and OH radicals in a concentration-dependent manner. Furthermore, KV significantly inhibited LPO in rats' liver homogenate. In vivo, administration of 4-Tabs caused a significant (p<0.05) decrease in body weight gain and weight of testis of rats. Body weight gain and weight of testis decreased by 45% and 36%, respectively, in the 4-Tabs-treated rats. Also, 4-Tabs increased testicular lipid peroxidation by 82%, with a concomitant decrease in antioxidant indices. Testicular reduced glutathione, superoxide dismutase and glutathione peroxidase decreased by 2.2-, 1.9- and 1.6-folds, respectively. Likewise, 4-Tabs markedly decreased sperm count, motility, luteinizing hormone and testosterone. Co-administration of KV with 4-Tabs normalized body weight, enhanced antioxidant system and improved sperm characteristics. CONCLUSIONS: Kolaviron protects male reproductive system from oxidative damage by anti-tuberculosis drugs via the antioxidative mechanism.

Comparison of antioxidant effects of kolaviron and vitamin C interventions on testicular structures following nevirapine administration in Sprague-Dawley rats / Comparación de los efectos antioxidantes en la intervención con kolaviron y vitamina C sobre las estructuras testiculares después de la administración de nevirapina en ratas Sprague-Dawley

Testicular toxicity has been implicated in highly active anti-retroviral therapy (HAART) treatment. Hence there is need to identify an effective antioxidant product that can alleviate testicular necrosis due to HAART administration. Forty eight adult male Sprague-Dawley rats were used in this study. The animals were divided into eight (8) groups: A-H (n= 6). Group A animals received normal saline as the control; Group B was given Nevirapine (Nv); Group C was given Kolaviron (Kv); Group D was given vitamin C; Group E was given Nv and Kv; Group F was given Nv and Vitamin C; Group G was given Nv for 56 d and Kv for 28 d serving as a withdrawal group; Group H was given corn oil. Nv, Kv and Vit. C were given at 1.54, 200 and 250 (mg·kg)/bw respectively while all administrations were through oral gavage. The body weights were taken every other day. Thereafter, they were anaesthetized with halothane. The testes were excised, weighed, fixed in Bouin's fluid and stained with H&E while the epididymes removed for semen fluid analyses. The results showed a significant (P<0.05) decrease in sperm motility in group E (Nevirapine + kolaviron) when compared with group F (Nevirapine + Vitamin C) while Sperm count was not significantly different (P>0.05) across the groups. The testicular histoarchitectural studies revealed indistinct spermatogonia, necrotic interstititial endocrine cells in the altered interstitial space, fragmented spermatids, atrophy of mature spermatocytes, degenerated germ cells, obliterated seminiferous tubules lumen, undifferentiated spermatogonia and cellular debris in the somniferous tubules lumen of nevirapine administered group but normal across the other groups. In the testis, there were no significant reduction in SOD, Catalase and GPx activities but a significant decrease in GST activity (P<0.001) when group E was compared with group F. In conclusion, vitamin C presents a better remediation in nevirapine induced spermiotoxicity compared to kolaviron in Sprague-Dawley rats.

La toxicidad testicular ha sido implicada en la terapia antirretroviral altamente activa (TARAA). Por lo tanto existe la necesidad de identificar un producto antioxidante eficaz que pueda aliviar la necrosis testicular en la administración de la TARAA. Cuarenta y ocho ratas macho Sprague-Dawley adultas fueron utilizadas. Los animales se dividieron en ocho (8) grupos: AH (n= 6). Grupo A, animales recibieron solución salina normal como el control; Grupo B, recibió Nevirapina (Nv); Grupo C, recibió Kolaviron (Kv); Grupo D, recibió vitamina C; Grupo E, recibió Nv y Kv; Grupo F, recibió Nv y vitamina C; Grupo G, recibió Nv durante 56 d y Kv por 28 d como un grupo de retirada; Grupo H, recibió aceite de maíz. Nv, Kv y Vit. C se administraron en dosis de 1, 54, 200 y 250 (mg · kg) de peso corporal respectivamente; todas las administraciones fueron por sonda oral. Los pesos corporales se tomaron cada dos días. A partir de ese momento los animales fueron anestesiados con halotano. Los testículos fueron extirpados, pesados y fijados en solución de Bouin y teñidos con H&E, mientras que el epidídimo se retiró para analizar el semen. Los resultados mostraron un descenso (p<0,05) en la motilidad de los espermatozoides en el grupo E (Nevirapina + Kolaviron) en comparación con el grupo F (Nevirapina + vitamina C), mientras que el recuento espermático no mostró diferencias significativas (P>0,05) entre los grupos. El estudio de la histoarquitectura testicular reveló espermatogonias indiferenciadas, con células intersticiales necróticas en el espacio intersticial y espermátidas fragmentadas. Además, en el grupo que recibió Nevirapina mostró espermatocitos maduros atrofiados, degeneración de células germinales, lumen de los túbulos seminíferos obliterados, espermatogonias indiferenciadas y restos celulares en el lumen de los tubulos seminíferos. En el resto de los grupos los resultados fueron normales. En el testículo hubo una reducción significativa en las actividades de la superóxido dismutasa, catalasa y glutatión peroxidasa, pero una disminución significativa en la actividad glutatión S-transferasa (P <0,001) al comparar los grupo E y F.

Kolaviron was protective against sodium azide (NaN3) induced oxidative stress in the prefrontal cortex.

Kolaviron is a phytochemical isolated from Garcina kola (G. kola); a common oral masticatory agent in Nigeria (West Africa). It is a bioflavonoid used--as an antiviral, anti-inflammatory and antioxidant--in relieving the symptoms of several diseases and infections. In this study we have evaluated the neuroprotective and regenerative effect of kolaviron in neurons of the prefrontal cortex (Pfc) before or after exposure to sodium azide (NaN3) induced oxidative stress. Separate groups of animals were treated as follows; kolaviron (200 mg/Kg) for 21 days; kolaviron (200 mg/Kg for 21 days) followed by NaN3 treatment (20 mg/Kg for 5 days); NaN3 treatment (20 mg/Kg for 5 days) followed by kolaviron (200 mg/Kg for 21 days); 1 ml of corn-oil (21 days-vehicle); NaN3 treatment (20 mg/Kg for 5 days). Exploratory activity associated with Pfc function was assessed in the open field test (OFT) following which the microscopic anatomy of the prefrontal cortex was examined in histology (Haematoxylin and Eosin) and antigen retrieval Immunohistochemistry to show astroglia activation (GFAP), neuronal metabolism (NSE), cytoskeleton (NF) and cell cycle dysregulation (p53). Subsequently, we quantified the level of Glucose-6-phosphate dehydrogenase (G6PDH) and lactate dehydrogenase (LDH) in the brain tissue homogenate as a measure of stress-related glucose metabolism. Kolaviron (Kv) and Kolaviron/NaN3 treatment caused no prominent change in astroglia density and size while NaN3 and NaN3/Kv induced astroglia activation and scar formation (astrogliosis) in the Pfc when compared with the control. Similarly, Kolaviron and Kv/NaN3 did not alter NSE expression (glucose metabolism) while NaN3 and NaN3/Kv treatment increased cortical NSE expression; thus indicating stress related metabolism. Further studies on enzymes of glucose metabolism (G6PDH and LDH) showed that NaN3 increased LDH while kolaviron reduced LDH in the brain tissue homogenate (P < 0.001). In addition kolaviron treatment before (P < 0.001) or after (P < 0.05) NaN3 treatment also reduced LDH expression; thus supporting its role in suppression of oxidative stress. Interestingly, NF deposition increased in the Pfc after kolaviron treatment while Kv/NaN3 showed no significant change in NF when compared with the control. In furtherance, NaN3 and NaN3/Kv caused a decrease in NF deposition (degeneration). Ultimately, the protective effect of KV administered prior to NaN3 treatment was confirmed through p53 expression; which was similar to the control. However, NaN3 and NaN3/Kv caused an increase in p53 expression in the Pfc neurons (cell cycle dysregulation). We conclude that kolaviron is not neurotoxic when used at 200 mg/Kg BW. Furthermore, 200 mg/Kg of kolaviron administered prior to NaN3 treatment (Kv/NaN3) was neuroprotective when compared with Kolaviron administered after NaN3 treatment (NaN3/Kv). Some of the observed effects of kolaviron administered before NaN3 treatment includes reduction of astroglia activation, absence of astroglia scars, antioxidation (reduced NSE and LDH), prevention of neurofilament loss and cell cycle regulation.

Effects of kolaviron on hepatic oxidative stress in streptozotocin induced diabetes.

BACKGROUND: Alteration in antioxidant defence and increase in oxidative stress that results in tissue injury is characteristic of diabetes. We evaluated the protective effects of kolaviron (a flavonoid complex extracted from the seeds of Garcinia kola) on hepatic antioxidants, lipid peroxidation and apoptosis in diabetic rats. METHODS: To induce diabetes, rats were injected with streptozotocin intraperitoneally at a single dose of 50 mg/kg. Kolaviron (100 mg/kg) was administered orally for 6 weeks (5 times weekly). Activities of liver antioxidant enzymes was analysed with Multiskan Spectrum plate reader. High performance liquid chromatography (HPLC) was used in the analysis of MDA (malondialdehyde), a product of lipid peroxidation. Apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. RESULT: Diabetic rats exhibited a significant increase in the peroxidation of hepatic lipids as observed from the elevated level of malondialdehyde (MDA). In addition, Oxygen Radical Absorbance Capacity (ORAC), level of reduced glutathione (GSH), ratio of reduced to oxidized glutathione (GSH: GSSG) and catalase (CAT) activity were decreased in the liver of diabetic rats. The activities of GPX (glutathione peroxidase) and SOD (superoxide dismutase) were unaltered in diabetic rats. TUNEL assay revealed increased apoptotic cell death in the liver. Kolaviron attenuated lipid peroxidation and apoptosis, increased CAT activity, GSH levels and GSH: GSSG ratio. The ORAC of kolaviron-treated diabetic liver was restored to near-normal values. CONCLUSION: Kolaviron protects the liver against oxidative and apoptotic damage induced by hyperglycemia.

Protective activity of biflavanones from Garcinia kola against Plasmodium infection.

ETHNOPHARMACOLOGICAL RELEVANCE: Garcinia kola is a medicinal plant traditionally used for malaria therapy in Central Africa. AIM OF THE STUDY: To evaluate the antimalarial potencies in vitro and in vivo of pure biflavanones from G. kola. MATERIALS AND METHODS: The pure biflavanones were obtained by bioassay-guided fractionation of a 70% ethanol extract of G. kola seeds and their chemical structures were elucidated by comparison of their NMR ((1)H and (13)C) and mass spectral data with those provided in the literature. Plasmodium falciparum (FCR-3, cycloguanil-resistant strain from Gambia) was used for in vitro assessments of antimalarial activities. Growth inhibition, intraerythrocytic development and parasite morphology were evaluated in culture by the microscopic observation of Giemsa-stained thin blood films. The cytotoxicity of the antimalarial compounds was evaluated against KB 3-1 (human epidermoid carcinoma) cells by MTT assay. In vivo antimalarial activities were determined in mice infected with Plasmodium berghei (ANKA strain) following a four-day suppressive test. RESULTS: The bioassay-guided fractionation of an extract of G. kola resulted in the isolation of three biflavanones (GB-1a, GB-1, and GB-2) as its active principles. These three biflavanones displayed not only potent inhibitory activity in vitro against P. falciparum proliferation but also antimalarial potency through oral administration in mice infected with P. berghei without signs of acute toxicity. GB-1 was found to exhibit the strongest in vitro antimalarial potency on P. falciparum with an IC50 of 0.16µM, whereas it exhibited a very low in vitro cytotoxicity on KB 3-1 cells with an IC50 of greater than 150µM. During an in vivo antimalarial assay in mice infected with P. berghei, GB-1 was found to exhibit biological potency with an approximate ED50 of 100mg/kg following oral administration. GB-1 was also shown to increase the average life span of the infected mice significantly compared to that of control mice (p<0.01 Student's t-test). CONCLUSIONS: The antimalarial outcome of GB-1a, GB-1, and GB-2 may be related to the traditional utilization of this crude drug against malaria judging from their significant content in G. kola nuts. GB-1 showed the most potent antimalarial activity with a high selectivity index and, therefore could be exploited to identify the molecular target, which subsequently could be helpful to design novel therapeutics against malaria. GB-1 may be considered a promising antimalarial candidate for trial in vivo using higher animals infected with P. falciparum.