Antidepressant-like effect of ethanol extract of Blighia unijugata Bak. (Sapindaceae) leaves in acute and chronic models of depression in mice.

Blighia unijugata (Sapindaceae) is an indigenous tree belonging to the tropical forests of West Africa. It is called "Ako Isin" by the Yoruba people of Southern-Western part of Nigeria, where it is among plants used traditionally in the management of depressive psychosis. The aim of this present study was to evaluate the anti-depressant activity of ethanol extract of Blighia unijugata leaves in-vivo using acute and chronic experimental models of depression. The antidepressant activity of ethanol extract of B. unijugata leaves was investigated using acute and chronic unpredictable mild stress. Depression tests used included forced swimming, tail suspension, yohimbine induced lethality and reserpine induced depression tests. Oxidative stress markers were also assessed in the brain homogenates after chronic unpredictable mild stress. The acute toxicity studied using oral route of administration was 1414 mg/kg. The results showed that, B. unijugata produced significant reduction in immobility time in forced swimming and tail suspension tests without stimulating in locomotor activity in open field test. It was also found that B. unijugata significantly reversed diarrhea, ptosis and hypothermia in reserpine model of depression. 2.5 mg/kg B. unijugata potentiated yohimbine induced lethality in mice and also reduced the oxidative stress markers. The ethanol extract of B. unijugata leaves possessed antidepressant action, thus justifying its use in the management of mental illness.

Anti-inflammatory activity of Theobroma cacao L. stem bark ethanol extract and its fractions in experimental models.

ETHNOPHARMACOLOGICAL RELEVANCE: The stem bark of Theobroma cacao L. have been used for the treatment of inflammation, toothache, measles and malaria in ethnomedicine. However, the anti-inflammatory activity of Theobroma cacao stem bark has not been fully elucidated. AIM: The anti-inflammatory activity of Theobroma cacao stem bark ethanol extract and its fractions was investigated in this study. MATERIALS AND METHODS: The anti-inflammatory effect of ethanol extract of Theobroma cacao stem bark (EETc) and its dichloromethane (DCMF), ethylacetate (EAF) and aqueous (AQF) fractions was investigated in erythrocytes membrane stabilizing assay and carrageenan-induced paw oedema. The anti-inflammatory activity of the EAF and EETc was investigated in carrageenan induced-granuloma air pouch models. RESULTS: The extract and fractions showed significant membrane stabilizing action on rat erythrocytes cell membrane. The oral administration of DCMF, EAF and AQF (250 mg/kg) significantly inhibited paw oedema induced by carrageenan (41.3%, 55.0% and 45.0%, respectively) compared to control group. The EAF (62.5, 125 and 250 mg/kg) and EETc (250 mg/kg) significantly inhibited exudates formation in carrageenan air pouch by (63.8, 71.5, 74.5, 64.3%) at 24 h and by (69.4%, 75.7%, 77.1% and 68.4%) at 72 h respectively. The EETc and EAF significantly reduced neutrophil counts, protein, nitrite, Tumor necrosis factor (TNF-α) and malondialdehyde (MDA) but increased reduced glutathione (GSH) levels compared to control in pouch exudates. The HPLC fingerprint of EAF revealed presence of caffeic acid, rutin, ferulic acid and morin. CONCLUSION: Ethanol extract of Theobroma cacao and its ethylacetate fraction demonstrated anti-inflammatory activity partly by reducing neutrophil migration and inflammatory mediator production.

Pharmacological Evaluation of Central Nervous System Effects of Ethanol Leaf Extract of Olax Subscorpioidea in Experimental Animals.

BACKGROUND: Olax subscorpioidea Oliv. (Olacaceae) is a medicinal plant used in folk medicine in the management of pain, mental illness, and convulsion. We evaluated neurosedative and anticonvulsant properties of the ethanol leaf extract of O. subscorpioidea (ELEOS). METHODS: Effects of ELEOS (3.125, 6.25, 12.5, 25 mg/kg) on novelty-induced behaviors were determined using open field test. Anxiolytic effect of ELEOS (3.125, 6.25, 12.5, 25 mg/kg) was assessed using hole-board and elevated-plus maze paradigms. The effect of O. subscorpioidea on pentobarbitone sleeping time was also investigated. Anticonvulsant property of ELEOS (12.5-50 mg/kg) was evaluated using pentylenetetrazole, picrotoxin and strychnine-induced convulsions assays. The extract was administered once intraperitoneally. RESULTS: The LD50 of ELEOS was 300 mg/kg. ELEOS (3.125, 6.25, 12.5, 25 mg/kg) significantly reduced rearing (99.8±2.8, 76.2±2.9, 37.4±1.2, 5.8±0.8) and grooming (48.0±3.6, 33.8±2.9, 25.4±1.6, 7.6±0.8) as compared with controls (185.8±5.1; 63.8±4.3). Treatment with ELEOS (3.125, 6.25, 12.5, 25 mg/kg) significantly reduced head-dipping on hole-board (10.6±1.9, 8.8±1.2, 7.2±0.9, 6.0±1.1) as compared with control (27.8±1.5). However, there was no anxiolytic effect on EPM. ELEOS (12.5, 25, 50 mg/kg) significantly prolonged pentobarbitone-induced sleeping time (43.0±1.4, 51.0±1.2, 61.0±1.8) as compared with control (31.0±0.7). At 50 mg/kg, ELEOS significantly prolonged onset of seizure (2.72±2.07) and latency to death (9.20±1.24) as compared with controls (0.54±0.02; 2.00±0.44) in pentylenetetrazole-induced convulsions with no effect on picrotoxin and strychnine-induced convulsions. CONCLUSION: The ELEOS is sedative and has mild anticonvulsant activity and this study supports pharmacological basis for its use in the management of mental illness and convulsion.

Neurobehavioural and Analgesic Properties of Ethanol Bark Extract of Terminalia ivorensis A Chev. (Combrataceae) in Mice.

BACKGROUND: Terminalia ivorensis A. Chev (Combretaceae) is a medicinal plant used in folk medicine in the management of pain, rheumatic condition, gastroenteritis and as a tranquilizer in psychotic disorder. OBJECTIVE: We evaluated neurobehavioural and analgesic properties of the ethanol bark extract of T. ivorensis (EBETI). MATERIALS AND METHODS: Effects of EBETI (1.25, 2.5, and 5 mg/kg) on novelty-induced behaviours were determined using open field test. Anxiolytic effect of EBETI (1.25, 2.5, and 5 mg/kg) was assessed using hole-board and elevated-plus maze paradigms. Analgesic property of EBETI (2.5, 5, and 10 mg/kg) was evaluated using acetic acid induced writhing, formalin and tail immersion tests. The extract was administered once intraperitoneally. RESULTS: The LD50 of EBETI was 173 mg/kg. EBETI (1.25, 2.5, and 5 mg/kg) significantly reduced rearing (142.3±1.6, 83.5±1.9, 39.3±1.5) and grooming (33.8±3.4, 28.4±3.0, 18.2±1.7) as compared with controls (180.5±4.9; 52.4±5.2). Treatment with EBETI (1.25, 2.5, and 5 mg/kg) significantly reduced head-dipping on hole-board (9.4±2.3, 6.2±1.9, 5.4±2.9) as compared with control (26.8±1.9). However, there was no anxiolytic effect on EPM. EBETI (2.5, 5, and 10 mg/kg) significantly inhibited abdominal constriction in writhing assay (21.8.0±2.4, 12.2±1.6, 5.8±2.1) as compared with control (35.0±1.7). Inhibition of neurogenic and inflammatory phases of formalin test was notice. However, the extract could not alter response to thermal stimulus in tail immersion test. DISCUSSION AND CONCLUSION: EBETI is sedative and has analgesic effect, thus supporting its folkloric use in pain management and as a tranquilizer in psychosis.

Evaluation of Antidepressant-like Effect of Olax Subscorpioidea Oliv. (Olacaceae) Extract in Mice.

Olax subscorpioidea is a shrub or tree found in Nigeria, and other parts of Africa. It is indicated in the management of inflammatory disorder, mental illness, convulsion, pain, and cancer.Based on the folkloric use in the management of mental illness, antidepressant activity of Olax subscorpioidea (6.25-50 mg/kg, i. p.) was investigated using forced swimming, tail suspension, yohimbine induced lethality and reserpine induced depression tests.The results showed that, Olax subscorpioidea produced significant dose dependent reduction in immobility time in forced swimming [F (5, 24) = 17.22, p < 0.0001] and tail suspension [F (5, 24) = 14.94, p < 0.0001] tests without causing changes in locomotor activity in open field test. It was also found that Olax subscorpioidea significantly reduced diarrhea in reserpine model of depression [F (5, 24) = 10, p < 0.0001]. None of the doses potentiated yohimbine induced lethality in mice. In conclusion Olax subscorpioidea possessed antidepressant action, thus justifying its use in the management of mental illness.

Free radical scavenging effect of donepezil as the possible contribution to its memory enhancing activity in mice.

Donepezil (DP) is the major drug currently used for enhancing memory function in patients with Alzheimer's disease (AD), an action ascribed to the elevation of central cholinergic neurotransmission. However, there are indications that DP may protect neurons against injury through the prevention of free radical-mediated neuroinflammation that has been implicated in the pathology of AD. Thus, this study was carried out to examine the effect of DP on memory impairment and on biomarkers of oxidative stress induced by scopolamine (SC) and lipopolysaccharide (LP) in mice.Mice were treated with DP (0.5-4 mg/kg, i. p.) 30 min prior to i. p. injection of SC or LP once daily for 7 days before assessing for memory function utilizing the Y-maze paradigm and levels of biomarkers of oxidative stress using standard biochemical procedures.DP (0.5-2 mg/kg) significantly reversed the memory impairment produced by SC (1 mg/kg) or LP (250 µg/kg) in mice, indicating memory enhancing effect. The increased brain levels of malondialdehyde (MDA) evoked by SC (1 mg/kg) or LP (250 µg/kg), was significantly inhibited by DP (0.5-4 mg/kg), suggesting antioxidant property. Further, DP (0.5-4 mg/kg) significantly inhibited glutathione (GSH) depletion caused by SC (1 mg/kg) or LP (250 µg/kg) in mice brains, which suggest free radical scavenging property.These findings suggest that DP has antioxidant effect, which might be playing a significant role in its memory enhancing activity in mice. However, more detailed studies are necessary to confirm the relevance of this finding and its implications in clinical settings.

Evaluation of the antidiabetic action of Mangifera indica in mice.

The leaves of Mangifera indica were assessed for antidiabetic properties using normoglycaemic, glucose-induced hyperglycaemia and streptozotocin (STZ) induced diabetic mice. The aqueous extract produced a reduction of blood glucose level in normoglycaemic and glucose-induced hyperglycaemia, but did not have any effect on streptozotocin-induced diabetic mice. The hypoglycaemic effect of the aqueous extract was compared with that of an oral dose of chlorpropamide under the same conditions. The results of this study indicate that the aqueous extract of the leaves of Mangifera indica possess hypoglycaemic activity.

Antihyperglycaemic effect of Mangifera indica in rat.

The leaves of Mangifera indica are used as an antidiabetic agent in Nigerian folk medicine. To determine whether or not there is a scientific basis for this use, the effect of the aqueous extract of the leaves on blood glucose level was assessed in normoglycaemic, glucose - induced hyperglycaemic and streptozotocin (STZ)-induced diabetic rats. The aqueous extract given orally (1 g/kg) did not alter the blood glucose levels in either normoglycaemic or STZ-induced diabetic rats. In glucose - induced hyperglycaemia, however, antidiabetic activity was seen when the extract and glucose were administered simultaneously and also when the extract was given to the rats 60 min before the glucose. The hypoglycaemic effect of the aqueous extract was compared with that of an oral dose of chlorpropamide (200 mg/kg) under the same conditions. The results of this study indicate that the aqueous extract of the leaves of Mangifera indica possess hypoglycaemic activity. This action may be due to an intestinal reduction of the absorption of glucose. However, other different mechanisms of action cannot be excluded.

Brief exposure to 95% oxygen alters surfactant protein D and mRNA in adult rat alveolar and bronchiolar epithelium.

Surfactant protein D (SP-D), which has structural homology to C-type lectin binding regions, may play a role in host defense and has no known surfactant function. Because other surfactant proteins have been shown to be increased after prolonged periods of hyperoxia, we sought to evaluate the early effects of hyperoxia (95% O2) on expression of SP-D in the adult male rat lung. Animals were exposed to air or to 12, 36, or 60 h of 95% O2. Northern blot analysis of total lung RNA revealed marked SP-D mRNA increases at 12 h 95% O2 compared with air-exposed controls, with decreasing expression to near that of air-exposed animals by 60 h. Semiquantitative in situ RNA hybridization demonstrated parallel results, with increased numbers of labeled alveolar epithelial (AE) and bronchiolar epithelial (BE) cells at 12 h and increased intensity of labeled alveolar cells, compared with air-exposed controls. After 60 h of exposure to 95% O2, mRNA label intensity in AE and BE was decreased to levels near those seen in air-exposed animals. In contrast, Western blotting showed a decline in total lung SP-D with 95% O2 exposure, beginning at 12 h and continuing at 36 and 60 h, respectively. Semiquantitative immunohistochemistry demonstrated a decline in AE labeling parallel to the total lung Western blot results, but labeled total BE cell numbers increased (P = 0.10). Hyperoxia had differential effects on SP-D abundance in AE and BE cells, and therefore may influence the availability of SP-D to bind microbial pathogens in the airways depending on cell type and location.

The antihyperglycamic effect of Telfaria occidentalis in mice.

The hypoglycemic effect of Telfaria occidentalis was studied in mice. The effect of the aqueous extract of the leaves on blood glucose level were assessed in normoglycaemic, glucose induced hyperglycaemic and streptozotocin (STZ) induced diabetic mice. The aqueous extract given orally in 1 g/kg did not alter the blood glucose level in normoglycaemic mice. In glucose-induced hyperglycemia, antidiabetic activity was seen when the extract and glucose were administered simultaneously and when the extract was giving to the mice 60 minutes before glucose. In STZ-induced diabetic mice, a reduction in the blood glucose level was seen from day two of the administration of the extract. The hypoglycemic effect of the aqueous extract was compared with that of an oral dose of chlorpropamide (200 mg/kg) under the same conditions. The results of this study indicate that the aqueous extract of the leaves of Telfaria occidentalis possess hypoglycaemic activity.