In vitro Anti-cholinesterase and Anti-oxidant Activity of Three Standardised Polyherbal Products Used for Memory Enhancing in Ethnomedicine of South-East Nigeria.

BACKGROUND: Polyherbal standardised extracts used in ethnomedicine of Eastern Nigeria for memory improvements were evaluated for anti-cholinesterases and anti-oxidant properties. METHODS: Anti-cholinesterase, anti-oxidant, and total phenolic and flavonoid contents were established using standard procedures. RESULTS: The three polyherbal extracts exhibited significant concentration dependent acetylcholinesterase (AChE) inhibitory activity (P = 0.001). The highest AChE inhibition was observed with the Neocare Herbal Tea (NHT) with 99.7% (IC50 = 324 µg/mL); whereas the Herbalin Complex Tea (HCT) and Phytoblis Herbal Tea (PHT) exhibited 73.8% (IC50 = 0.2 µg/mL) and 60.6% (IC50 = 0.7 µg/mL) inhibition, respectively, relative to eserine at 100% inhibition (IC50 = 0.9 µg/mL) at 200 µg/mL. The order of percentage increase in inhibition of AChE was NHT > HCT > PHT; while the order of decrease in potency was HCT > PHT > NHT.Radical scavenging activities of HCT, NHT and PHT were 82.13% (IC50 = 0.08 µg/mL), 77.43% (IC50 = 0.01 µg/mL) and 76.28% (IC50 = 0.3 µg/mL), respectively, at 1 mg/mL concentrations. The reducing power revealed a dose-dependent effect, with NHT > PHT > HCT. The order of total phenolics content in the extracts were PHT > HCT > NHT, and for total flavonoids content: PHT > NHT > HCT. CONCLUSION: The three polyherbal standardised products possess significant acetylcholinesterase inhibitory activity and secondary metabolites that could collectively contribute to their memory-enhancing effects.

Anti-acetylcholinesterase activity and antioxidant properties of extracts and fractions of Carpolobia lutea.

CONTEXT: There is an unmet need to discover new treatments for Alzheimer's disease. This study determined the anti-acetylcholinesterase (AChE) activity, DPPH free radical scavenging and antioxidant properties of Carpolobia lutea G. Don (Polygalaceae). OBJECTIVE: The objective of this study is to quantify C. lutea anti-AChE, DPPH free radical scavenging, and antioxidant activities and cell cytotoxicity. MATERIALS AND METHODS: Plant stem, leaves and roots were subjected to sequential solvent extractions, and screened for anti-AChE activity across a concentration range of 0.02-200 µg/mL. Plant DPPH radical scavenging activity, reducing power, and total phenolic and flavonoid contents were determined, and cytotoxicity evaluated using human hepatocytes. RESULTS: Carpolobia lutea exhibited concentration-dependent anti-AChE activity. The most potent inhibitory activity for the stem was the crude ethanol extract and hexane stem fraction oil (IC50 = 140 µg/mL); for the leaves, the chloroform leaf fraction (IC50 = 60 µg/mL); and for roots, the methanol, ethyl acetate and aqueous root fractions (IC50 = 0.3-3 µg/mL). Dose-dependent free radical scavenging activity and reducing power were observed with increasing stem, leaf or root concentration. Total phenolic contents were the highest in the stem: ∼632 mg gallic acid equivalents/g for a hexane stem fraction oil. Total flavonoid content was the highest in the leaves: ∼297 mg quercetin equivalents/g for a chloroform leaf fraction. At 1 µg/mL, only the crude ethanol extract oil was significantly cytotoxic to hepatocytes. DISCUSSION AND CONCLUSIONS: Carpolobia lutea possesses anti-AChE activity and beneficial antioxidant capacity indicative of its potential development as a treatment of Alzheimer's and other diseases characterized by a cholinergic deficit.

Telfairia occidentalis (Cucurbitaceae) pulp extract mitigates rifampicin-isoniazid-induced hepatotoxicity in an in vivo rat model of oxidative stress.

OBJECTIVE: Drug-induced liver injury complicates antituberculosis drug treatment and is a leading cause of death worldwide. The aim of this study is to establish the ethnomedicinal claim of hepatoprotective effects of fruit pulp extract of Telfairia occidentalis against rifampicin (RIF) and isoniazid (INH)-induced oxidative stress in rats. METHODS: T. occidentalis pulp extract (TOPE) (125-500 mg/kg) and silymarin (50 mg/kg) were evaluated in an induced hepatotoxicity model of oxidative stress in Wistar rats by intoxication with RIF and INH (100 mg/kg each) orally for 60 d. Markers indicating oxidative stress and hepatic damage such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were assessed. Biomarkers of antioxidant status, including catalase, glutathione reductase, glutathione peroxidase and superoxide dismutase, and marker of lipid peroxidation, malondialdehyde (MDA), were assayed using standard procedures. The hematological profile, lipid profile, serum markers for kidney function and histopathological examination were also assessed. RESULTS: Intoxication with RIF and INH markedly reduced the hematological indices and elevated the biochemical enzyme markers (AST, ALT and ALP, P < 0.001) and lipid profile (P < 0.001), while antioxidant biomarkers were significantly (P < 0.01) depressed and MDA was elevated. However, pretreatment with TOPE significantly (P < 0.001) alleviated this alteration and sustained the antioxidant potentials. The histopathological morphology supports the biochemical evidence of hepatoprotection. CONCLUSION: Current study is indicative of potential antioxidant activity, hepatoprotective effects and plausible therapeutic alleviation of RIF-INH-induced hepatotoxicity of TOPE in laboratory animals.

An Investigation of Potential Sources of Nutraceuticals from the Niger Delta Areas, Nigeria for Attenuating Oxidative Stress.

Background: Diets rich in fruits, vegetables, and medicinal plants possess antioxidants potentially capable of mitigating cellular oxidative stress. This study investigated the antioxidant, anti-acetylcholinesterase (AChE), and total phenolic and flavonoids contents (TPC/TFC) of dietary sources traditionally used for memory enhancing in Niger Delta, Nigeria. Methods: Dacroydes edulis methanolic seed extract (DEMSE), Cola lepidota methanolic seed extract (CLMSE), Terminalia catappa methanolic seed extract (TeCMSE), Tricosanthes cucumerina methanolic seed extract (TrCMSE), Tetrapleura tetraptera methanolic seed extract (TTMSE), and defatted Moringa oleifera methanolic seed extract (DMOMSE); Dennettia tripetala methanolic fruit extract (DTMFE), Artocarpus communis methanolic fruit extract (ACMFE), Gnetum africana methanolic leaf extract (GAMLE), Musa paradisiaca methanolic stembark extract (MPMSE), and Mangifera indica methanolic stembark extract (MIMSE) were evaluated for free radical scavenging antioxidant ability using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), reducing power capacity (reduction of ferric iron to ferrous iron), AChE inhibitory potential by Ellman assay, and then TPC/TFC contents determined by estimating milli-equivalents of Gallic acid and Quercetin per gram, respectively. Results: The radical scavenging percentages were as follows: MIMSE (58%), MPMSE (50%), TrCMSE (42%), GAMLE (40%), CLMSE (40%), DMOMSE (38%), and DEMFE (37%) relative to ß-tocopherol (98%). The highest iron reducing (antioxidant) capacity was by TrCMSE (52%), MIMSE (40%) and GAMLE (38%). Extracts of MIMSE, TrCMSE, DTMFE, TTMSE, and CLMSE exhibited concentration-dependent AChE inhibitory activity (p < 0.05⁻0.001). At a concentration of 200 µg/mL, the AChE inhibitory activity and IC50 (µg/mL) exhibited by the most potent extracts were: MIMSE (≈50%/111.9), TrCMSE (≈47%/201.2), DTMFE (≈32%/529.9), TTMSE (≈26%/495.4), and CLMSE (≈25%/438.4). The highest TPC were from MIMSE (156.2), TrCMSE (132.65), GAMLE (123.26), and CLMSE (119.63) in mg gallic acid equivalents/g, and for TFC were: MISME (87.35), GAMLE (73.26), ACMFE (69.54), CLMSE (68.35), and TCMSE2 (64.34) mg quercetin equivalents/gram. Conclusions: The results suggest that certain inedible and edible foodstuffs, most notably MIMSE, MPMSE, TrCMSE, GAMLE, and CLMSE may be beneficial to ameliorate the potentially damaging effects of redox stress.

Hot aqueous leaf extract of Lasianthera africana (Icacinaceae) attenuates rifampicin-isoniazid-induced hepatotoxicity.

OBJECTIVES: The aim of this study is to evaluate the hepatoprotective effect of Lasianthera africana (Icacinaceae) against isoniazid (INH) and rifampicin (RIF)-induced liver damage in rats. METHODS: The hepatoprotective effects of hot aqueous L. africana (HALA) leaf extract (0.1-1 g/kg) and silymarin (50 mg/kg) were assessed in a model of oxidative liver damage induced by RIF and INH (100 mg/kg each) in Wistar rats for 28 days. Biochemical markers of hepatic damage such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were assessed. The antioxidant statuses of plasma glutathione peroxidase (GSPx), glutathione reductase (GSH), catalase (CAT) and superoxide dismutase (SOD) and lipid peroxidation were evaluated. RESULTS: The pretreatment of INH and RIF decreased hematological indices and the antioxidant levels (P < 0.001) and increased the levels of liver marker enzymes (P < 0.001). However, pretreatment with HALA extract and silymarin provoked significant elevation of hematological indices. The levels of AST, ALT, and ALP were depressed (P < 0.001). Total triglycerides, total cholesterol, total bilirubin and low-density lipoprotein were decreased (P < 0.001). However, high-density lipoprotein, bicarbonate, and electrolytes like chloride and potassium were elevated (P < 0.001), but sodium was depressed (P < 0.05). Additionally, GSH, GSPx, SOD and CAT were elevated (P < 0.01) and malondialdehyde was depressed (P < 0.001) when compared to the RIF-INH-treated rats. Histopathological evaluations support hepatoprotective activity. CONCLUSION: This study demonstrated that HALA leaf extract attenuated RIF-INH-induced hepatotoxicity. L. africana could be exploited in management of RIF-INH-induced hepatitis.

In Vitro Anti-Cholinesterase and Antioxidant Activity of Extracts of Moringa oleifera Plants from Rivers State, Niger Delta, Nigeria.

This study evaluated Moringa oleifera extracts from two locations in Niger Delta for in vitro anti-cholinesterase and antioxidant activities. Methanolic, aqueous and ethanolic extracts of Moringa oleifera were evaluated for inhibition of acetylcholinesterase (AChE) activity, antioxidant properties, and total phenolic and flavonoid contents using standard procedures. M. oleifera extracts possessed significant and concentration dependent AChE inhibitory activity for methanolic, aqueous, and ethanolic extracts. For the most potent extracts, the percentage AChE inhibition/IC50 (µg/mL) values were Moringa oleifera root methanolic extracts (MORME): ~80%/0.00845; Moringa oleifera root ethanolic extract 1 (MOREE1): ~90%/0.0563; Moringa oleifera root ethanolic extract 2 (MOREE2): ~70%/0.00175; and Moringa oleifera bark ethanolic extract (MOBEE): ~70%/0.0173. The descending order of AChE inhibitory potency of plant parts were: root > bark > leaf > flowers > seed. All M. oleifera methanolic extracts at a concentration of 1000 µg/mL displayed significant (p < 0.05⁻0.001) DPPH radical scavenging activity, with values of ~20⁻50% of that of ascorbic acid. The total phenolic content and total flavonoid content (TPC/TFC) of MORME, Moringa Oju bark methanolic extract (MOBME), MOREE1, MOREE2 and Moringa leaf ethanolic leaf extract (MLEE) were (287/254), (212/113), (223/185), (203/343) and (201/102) mg gallic acid equivalents/g and quercetin equivalents/g, respectively. There was an inverse correlation between plant extract AChE inhibition and total phenolic (p < 0.0001) and total flavonoid contents (p < 0.0012). In summary, this study revealed 5 of 19 extracts of M. oleifera that have potent in vitro anti-cholinesterase and antioxidant activities.

Alleviation of carbon tetrachloride-induced hepatocellular damage and oxidative stress with a leaf extract of Glyphae brevis (Tiliaceae).

Background Glyphae brevis leaf is reported in ethnomedicine as a treatment for hepatitis and jaundice; however, no studies have hitherto investigated the mechanistic basis of these claims. Methods A hepato-protective role of G. brevis hydromethanolic (GBH) leaf extract was established against carbon tetrachloride (CCl4)-induced hepatotoxicity. Twenty-four hours after a CCl4 challenge, rats were sacrificed and serum hematological indices, lipid profile, and biochemical parameters were determined. The antioxidant enzymes parameters (glutathione, catalase, and superoxide dismutase) and lipid peroxidation product (thiobarbituric reactive substances) levels in liver homogenates were evaluated. Changes in the liver cyto-architecture of different treatment groups were also investigated. Results The GBH extract produced no significant impact on weight and hematological indices. Intoxication with CCl4 significantly (p<0.001-0.05) increased total cholesterol (TC) and low-density lipoproteins (LDL) compared with control rats. Pretreatment with GBH leaf extract significantly reduced triglycerides, TC, and LDL to approaching control levels (p<0.001-0.05). The GBH leaf extract significantly alleviated CCl4-induced elevation of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and the CCl4-induced depression of total protein, and albumin. Liver antioxidant parameters were significantly increased in plant extract-treated rats, and this antagonized the pro-oxidant effect of CCl4. Histopathological studies also supported a hepato-protective effect of GBH. Collectively, the GBH leaf extract alleviated the CCl4-induced hepatotoxicity through improvement of innate antioxidant enzyme levels and lipid metabolism and stabilized the hepatocyte cyto-architecture of intoxicated rats. Conclusions This study establishes the ethnomedicinal role of G. brevis leaf in hepatitis and the mechanistic basis of hepato-protection against CCl4-induced hepatotoxicity.

Anti-inflammatory and antinociceptive activities of Solenostemon monostachyus aerial part extract in mice.

OBJECTIVE: Solenostemon monostachyus is used in traditional medicine for the treatment of various ailments such as ulcer, hypertension, pains and inflammatory diseases. Evaluation of anti-inflammatory and analgesic activities of S. monostachyus aerial parts was carried out to ascertain its uses in traditional medicine. MATERIALS AND METHODS: The aerial parts of S. monostachyus was cold extracted by soaking the dried powdered material in ethanol. The aerial parts crude extract (75 -225 mg/kg) of S. monostachyus was investigated for analgesic and anti-inflammatory activities using various experimental models; acetic acid, formalin and thermal- induced pains models for analgesic study and carrageenin, egg albumin and xylene - induced edema models for anti-inflammatory investigation. RESULTS: The extract caused a significant (p<0.05 - 0.001) dose-dependent reduction of inflammation and pains induced by different phlogistic agents used. These effects were comparable to those of the standard drug, (ASA, 100 mg/kg) used in some models. CONCLUSION: The anti-inflammatory and analgesic effects of this plant may in part be mediated through the chemical constituents of the plant and the results of the analgesic action suggest central and peripheral mechanisms. The findings of this work confirm the ethno medical use of this plant to treat inflammatory conditions.

Anti-Inflammatory and Anti-Nociceptive Activities of Stem-Bark Extracts and Fractions of Carpolobia Lutea (Polygalaceae).

BACKGROUND: In Niger Delta, ethnomedicine hydroalcoholic extract of Carpolobia lutea (CL) (Polygalaceae) is used to relieve inflammatory pains. OBJECTIVES: The purpose of this study is to evaluate the anti-inflammatory and antinociceptive effects of ethanolic stem extract (ESE) and to fractionate the ESE for the elucidation of bioactive molecules. MATERIALS AND METHODS: The antinociceptive effects for ESE were tested against two noxious stimuli; chemical (acetic acid-induced writhing and formalin-induced pain) and thermal (hot plate) stimuli. The effects of paracetamol (130 mg/kg), indomethacin (10 mg/kg), and morphine (5 mg/kg) pretreatment were investigated. To isolate the bioactive compounds with anti-inflammatory effect, two doses (86.6 and 173.2 mg/kg) of four fractions (methanol fraction MTF, ethyl acetate fraction EAF, chloroform fraction CHF, and n-hexane fraction n-HF) obtained from fractionating ESE were utilized. Carrageenan, egg albumin, and capsaicin-induced edema of the hind paw of the rats were the models adopted. Paw volume was measured by a digital vernier caliper from 0 to 6 h after injection. This was compared to standard drugs. The results were subjected to statistical analysis. RESULTS: The ESE decreased significantly (P < 0.001) the writhing of acetic acid-induced abdominal contractions and licking of formalin-induced pains but does not have any effects on the hot plate test. Of the four fractions obtained, the EAFs demonstrated a significant (P < 0.001) inflammatory inhibition of 98.97% and 41.91% at 86.6 and 173.2 mg/kg, respectively, compared to 65.75% inhibition demonstrated by the reference drug, acetylsalicylic acid (100 mg/kg) on the carrageenan model while 36.36% and 29.87% inhibition of inflammation at 86.6 and 173.2 mg/kg, respectively, on the egg albumin models; there was no significant effect on the capsaicin model. CONCLUSION: The isolation of quercetin and kaemferol from CL gave credence to its anti-inflammatory and antinociceptive effects.

Antidiarrheal mechanism and ionic profile of Carpolobia lutea ethanolic stem-bark extract in rats.

BACKGROUND: The stem-bark extract of Carpolobia lutea (Polygalaceae), used in ethno-medicine as anti-diarrhea was pharmacologically evaluated. This was the first report of assessment of the ethanolic stem extract (ESE), of C. lutea as anti-diarrhoeal agent in rats. The anti-diarrhoeal effects, acute toxicity and ionic profile are investigated and reported. MATERIALS AND METHODS: The acute toxicity was established using Lock's method. The anti-diarrhoeal effects were demonstrated using castor oil-induced diarrheal and fluid accumulation and its effect on normal intestinal transit. The mechanism elucidated using yohimbine, isosorbide dinitrate, and diphenoxylate. The elemental and ionic profile of ESE was established using inductively coupled argon-plasma emission spectrometer and potentiometric titration respectively. The finger print of ESE was revealed by Jasco (Tokyo, Japan), HPLC and active compounds by phytochemical screening using standard procedure. RESULTS: The LD50 obtained is 866.025 mg/kg (i.p). The doses of 43.3, 86.6, and 173.2 mg/kg of ESE showed inhibition of castor oil-induced diarrheal (p<0.05 -0.001). The most abundant cations in the extract are potassium and phosphorus (1.00 ±0.01 and 0.80 ± 0.030 mg/g respectively); while the most abundant anions are phosphate and sulphate (33.50±7.09 and 7.19±3.29 mg/g respectively). The HPLC fingerprint of ESE revealed UV spectra of biomolecules. Phytochemical screening revealed presence of saponins, polyphenols and glycosides. CONCLUSION: These investigations indicate presence of bioactive and elemental substances which could play major role in diarrheal management. This investigation justifies the use of stem-bark of C. lutea in illicit gin (akpatashi), among the Effiks in Nigeria as antidiarrheal.