Search tips
Search criteria

Results 1-6 (6)

Clipboard (0)

Select a Filter Below

Year of Publication
Document Types
1.  Immunomodulatory effects of Stachytarpheta cayennensis leaf extract and its synergistic effect with artesunate 
The leaves of Stachytarpheta cayennensis C. Rich. (Verbenaceae) have been reported to possess potent anti-inflammatory and anti-malarial activities. Due to close association between inflammatory and immune responses, we evaluated the immunomodulatory activity of leaves extract of S. cayennensis. The combined effects of the leaves extract and artesunate, a standard antimalarial agent with immunomodulatory effects, were also evaluated.
The immunomodulatory activity of the methanol extract of the leaves of S. cayennensis (MESC) was evaluated in mice using the Delayed-Type hypersensitivity response (DTHR), primary and secondary humoral immune responses and the in vivo leucocyte mobilization tests. The immunomodulatory effect of artesunate and the combined effects of MESC and artesunate were evaluated using the phagocytic activity of polymorphonuclear neutrophils. Acute toxicity and lethality test in addition to the preliminary phytochemical studies of MESC were also performed.
The MESC exhibited 64.21% inhibition of DTHR at 500 mg/kg dose and evoked 139.64% of phagocytic stimulation at 100 μg/ml dose. Also MESC significantly (p < 0.05) showed dose related stimulation of humoral immunity and a highest percentage leucocyte mobilization of 10.15% at 250 mg/kg dose. Artesunate offered a non-significant (p > 0.05) percentage phagocytic stimulation (PPS) while the combined effect of artesunate and MESC exhibited a significant (p < 0.05) dose dependent PPS with highest PPS of 393.77% at 100 μg/ml. The LD50 of the MESC was estimated to be greater than 5000 mg/kg since there were no lethality and signs of acute intoxication after 48 h observation. Preliminary phytochemical analysis revealed the presence of carbohydrates, glycosides, flavonoids, saponins, alkaloids, terpenoids and steroids.
The results of this study indicated that MESC possesses immunostimulatory action with significant synergistic effects with artesunate, and can therefore, offer immune boosting activities in disorders of immune suppression.
PMCID: PMC4195953  PMID: 25283179
Cellular mediated immunity; Delayed type hypersensitivity; Immunomodulatory action; Stachytarpheta cayennensis; Artesunate
2.  Wound-healing Activity of the Aqueous Leaf Extract and Fractions of Ficus exasperata (Moraceae) and its Safety Evaluation on Albino Rats 
Ficus exasperata have been reported to have wide applications in the treatment of many human diseases. However, its traditional use in the treatment of wounds has not been validated by any scientific study. Also, its safety in the management of chronic disease conditions requires attention. We evaluated the wound-healing activity of the aqueous extract and fractions of F. exasperata, as well as its safety after subchronic oral administration. Similar percentage of wound contraction was observed with 5% w/w extract ointment application and administration of cicatrin powder (standard) on the 4th day, while better contraction than the standard was recorded with higher concentrations of the extract ointment. Of all the fractions tested, significant (P < 0.05) contraction was only noticed in chloroform fraction, though lower than that of the aqueous extract. The extract also showed concentration-dependent inhibition of all the tested microbial isolates. Extract administered up to 5000 mg/kg (single dose administration) did not cause any mortality after 24 h. Mortality was, however, recorded at 4000 mg/kg within the first 20 days of subchronic administration of the extract. Significant (P < 0.05) increases in alanine aminotransaminase (ALT), aspartate aminotransaminase (AST), and in particular, alkaline phosphatase (ALP) were observed at different doses and time periods. Pathological and histological changes were noticed in the liver and kidney on the 91st day of the study with 4000 mg/kg of the extract. Except for the significant (P < 0.05) reduction in WBC on the 91st day, no other significant (P < 0.05) changes were observed in other hematological parameters. The aqueous extract demonstrated better wound-healing activity than its fractions; however, the extract may not be safe at higher doses for subchronic oral administration, as may be the case in the management of chronic disease conditions.
PMCID: PMC4220502  PMID: 25379466
Chronic diseases; Ficus exasperata; Hematological parameters; Liver enzymes; Toxicity; Wound healing
3.  Antimicrobial Effects of a Lipophilic Fraction and Kaurenoic Acid Isolated from the Root Bark Extracts of Annona senegalensis 
Root bark preparation of Annona senegalensis Pers. (Annonaceae) is used in Nigerian ethnomedicine for treatment of infectious diseases. Extraction of the A. senegalensis powdered root bark with methanol-methylene chloride (1 : 1) mixture yielded the methanol-methylene extract (MME) which was fractionated to obtain the ethyl acetate fraction (EF). The EF on further fractionation gave two active subfractions, F1 and F2. The F1 yielded a lipophilic oily liquid while F2 on purification, precipitated white crystalline compound, AS2. F1 was analyzed using GC-MS, while AS2 was characterized by proton NMR and X-ray crystallography. Antibacterial and antifungal studies were performed using agar-well-diffusion method with 0.5 McFarland standard and MICs calculated. GC-MS gave 6 major constituents: kaur-16-en-19-oic acid; 1-dodecanol; 1-naphthalenemethanol; 6,6-dimethyl-bicyclo[3.1.1]hept-2-ene-2-ethanol; 3,3-dimethyl-2-(3-methylbuta-1,3-dienyl)cyclohexane-1-methanol; 3-hydroxyandrostan-17-carboxylic acid. AS2 was found to be kaur-16-en-19-oic acid. The MICs of EF, F1, and AS2 against B. subtilis were 180, 60, and 30 μg/mL, respectively. AS2 exhibited activity against S. aureus with an MIC of 150 μg/mL, while F1 was active against P. aeruginosa with an MIC of 40 μg/mL. However, the extracts and AS2 exhibited no effects against Candida albicans and Aspergillus niger. Therefore, kaurenoic acid and the lipophilic fraction from A. senegalensis root bark exhibited potent antibacterial activity.
PMCID: PMC3366254  PMID: 22675389
4.  Efficacy and Safety Assessment of T. Angelica Herbal Tonic, a Phytomedicinal Product Popularly Used in Nigeria 
T. Angelica Herbal Tonic (TAHT) is a herbal product indicated for indigestion and constipation and highly patronized in Nigeria. In this study, the efficacy and safety of the herbal tonic in relation to the label claims were assessed. The effect on peristalsis in mice was evaluated by the charcoal meal model and in vitro using guinea pig ileum. The effects of TAHT on behavior, fertility, birth and organ weights were also determined. Teratogenic potential and reproductive toxicity were studied in pregnant rats. Acute toxicity studies showed that at doses above 5000 mg kg−1, the herbal tonic did not cause lethality and produced no signs of intoxication in mice. The study did not show any gross behavioral changes in mice treated with 1000 mg kg−1 of TAHT as compared with the negative control treatment. TAHT (400 mg kg−1) exhibited a dose-dependent enhancement in the gastrointestinal tract motility in mice when compared with the negative control. At concentrations up to 300 μg mL−1, TAHT did not cause any significant effect on acetylcholine, histamine and nicotine-evoked contractions of guinea pig ileum preparation. It took an average of 31.25 ± 4.52 days for the TAHT-treated animals to litter, which is significantly (P < .05) different from the 55 ± 4.51 days recorded for the control treatment group. TAHT exhibited a modest fertility-promoting effect and showed lack of abortifacient and teratogenic properties in the study. Generally, the results of this study showed some favorable pharmacological effects of TAHT in animals which may authenticate some of the label claims.
PMCID: PMC3094697  PMID: 19812180
The antidiabetic activity of methanol leaves extract of Cajanus cajan (L.) Millsp. (Fabaceae) was studied in alloxan-diabetic and in oral glucose loaded rats. The acute toxicity and lethality (LD50) and the phytochemical analysis of the extract were also evaluated. The results showed that the extract (400 and 600 mg/kg) significantly (P<0.05) reduced fasting blood sugar of alloxan diabetic rats in a dose-related manner, with maximum hypoglycemic effect at 4 – 6 h. The extract (400 and 600 mg/kg) also significantly (P<0.05) suppressed the peak postprandial rise in blood glucose of normal rats by 101.8 and 57.40% respectively. Acute toxicity and lethality test of the extract in rats gave an oral LD50 greater than 5 g/kg. The findings indicate that the leaves of C. cajan may be beneficial as an antidiabetic therapy.
PMCID: PMC3979181  PMID: 24825970
Cajanus cajan; alloxan; hypoglycemia; postprandial
6.  Acanthus montanus: An experimental evaluation of the antimicrobial, anti-inflammatory and immunological properties of a traditional remedy for furuncles 
Acanthus montanus (Nees) T. Anderson (Acanthaceae) is a shrub widespread in Africa, the Balkans, Romania, Greece and Eastern Mediterranean. It is used in African traditional medicine for the treatment of urogenital infections, urethral pain, endometritis, urinary disease, cystitis, leucorrhoea, aches and pains. In southeastern Nigeria, the root is popular and acclaimed highly effective in the treatment of furuncles. This study was undertaken to experimentally evaluate the antimicrobial and anti-inflammatory properties of the root extract as well as its effect on phagocytosis and specific cell-mediated immune response which may underlie the usefulness of the roots in treatment of furuncles.
The aqueous root extract (obtained by hot water maceration of the root powder) was studied for effects on the growth of clinically isolated strains of Pseudomonas aeruginosa and Staphylococcus aureus. The anti-inflammatory activity was investigated using acute topical edema of the mouse ear induced by xylene, acute paw edema induced by agar in rats, formaldehyde arthritis in rats, vascular permeability induced by acetic acid in mice and heat- and hypotonicity-induced haemolysis of ox red blood cells (RBCs). Also evaluated were the effects on in vivo leukocyte migration induced by agar, phagocytic activity of macrophages on Candida albicans and specific cell-mediated immune responses (delayed type hypersensitivity reaction (DTHR) induced by sheep red blood cell (SRBC)). The acute toxicity and lethality (LD50) in mice and phytochemical constituents of the extract were also determined.
The extract moderately inhibited the growth of the test organisms and significantly (P < 0.05) inhibited (57%) topical acute edema in the mouse ear. It significantly (P < 0.05) suppressed the development of acute edema of the rat paw in a non-dose-related manner and was not effective in inhibiting the global edematous response to formaldehyde arthritis. It also inhibited vascular permeability induced by acetic acid in mice and the haemolysis of ox RBCs induced by heat- and hypotonicity. The extract increased total leukocyte and neutrophil counts and caused a significant (P < 0.05) dose-related increase in the total number of macrophages at the 800 mg/kg dose. On phagocytic activity, the extract evoked a significant (P < 0.05) increase in the number of macrophages with ingested C. albicans at 800 mg/kg dose, and significantly (P < 0.05) inhibited DTHR in a dose-related manner. Phytochemical tests on the extract revealed an abundant presence of alkaloids and carbohydrates while saponins, glycosides, and terpenoids occurred in trace amounts. Acute toxicity test established an oral and intraperitoneal LD50 greater than 5,000 mg/kg.
The effectiveness of the root of A. montanus in the treatment of furuncles may largely derive from mobilization of leukocytes to the site of the infection and activation of phagocytic activity as well as suppression of exacerbated immune responses by its constituents. Antimicrobial and anti-inflammatory activities are likely contributory mechanisms. Phytochemical constituents such as alkaloids and carbohydrates may be responsible for these pharmacological activities.
PMCID: PMC2453109  PMID: 18538006

Results 1-6 (6)