The avalanche of data on the immunomodulatory and anti-cancer activites of the European
mistletoe, Viscum album especially with respect to its lectin constituents have been well documented [1].
These activities are always dependent on the season and host tree from which the plant
material was harvested. The antimicrobial, antidiabetic and antimotility activities
of the Eastern Nigeria mistletoe, Loranthus micranthus Hook. f. (Loranthaceae) have been reported [2,3,4]. Preliminary phytochemical evaluation
showed presence of tannins, flavonoids, alkaloids, terpenoids, proteins, carbohydrates
and saponins. Preliminary investigation with the crude aqueous (hot and cold extraction),
methanolic (hot and cold extraction) and n-hexane (hot and cold extraction) extract
of the mistletoe extract harvested in early January 2007 showed marked immunostimulatory
activity using the total and differential leucocyte count, the delayed hypersensitivity
reaction (DTH) and antibody titration models at three different dose levels of 50,
100, and 200mg/kg body weight in mice and rats. We observed a dose dependent increase
in total and differential leukocyte count by well over 90% compared to the control
(p<0.05, one-way ANOVA and Student t-test). Higher doses did not show any further
benefit. The average increase in indurations in mice footpads in the presence of the
extracts by 13, 47.8 and 56% followed similar trends as above. The mean antibody titre
values increased by 100, 120, and 185% (p<0.05 compared to control) respectively at
the tested dose levels of the extract. The results were all subjected to statistical
analysis and no significant differences in respect to host tree variation were observed
(P<0.001).
Acknowlegement: The authors are thankful to Mr. Ozioko of Bio resource Development
and Conservation Centre, Nsukka, Enugu state for collection and authentication of
the plant material from different host trees.
References: [1] Becker H, (1986) Oncology 43: 2–7. [2] Osadebe PO and Akabogu IC (2006) Fitoterapia
7; 54–56
3. Osadebe PO, Okide GB and Akabogu IC, (2004), J. Ethnopharmacol. 95: 133–138. 4.
Osadebe PO and Uzochukwu IC (2006), J. Pharm. Allied Sci. 3: 263–268.
