Mistletoe Ain't Just for Kissing

A study of extracts of African mistletoe shows it to have anti-diabetic activity, according to researchers in Nigeria.

P.O. Osadebe, G.B. Okide, and I.C. Akabogu of the Department of Pharmaceutical Chemistry, at the University of Nigeria in Nsukka, Enugu State, obtained crude methanolic extracts of the Eastern Nigerian mistletoe Loranthus micranthus from five different host trees of this cousin of the well-known festive parasite and have tested its hypoglycemic and anti-hyperglycemic activities.


Credit: USGS

Mistletoe is a parasitic tree hugger so attractive to lovers at Christmas, but it could turn out to be more than a poisonous excuse for a kiss, according to the researchers. The African variety is parasitic on many species of tree, but Osadebe and his colleagues focused on Persea Americana (avocado), Baphia nitida, Cola acuminata (kola nut), Pentaclethra macrophylla (oil bean), and Azadirachta indica (neem). Dried mistletoe leaves from these trees, and indeed, the leaves of the trees themselves, have been used in Nigerian folk medicine for many generations as a remedy for various ailments including inflammation, infection, and fever.

The researchers evaluated the extracts on normoglycemic and alloxan-induced diabetic rodents and found that blood sugar levels as determined by o-toluidine spectrophotometry indicated that the crude methanolic extracts exhibited statistically significant hypoglycemic and anti-hyperglycemic activity in both groups. The hypoglycemic effect was found to be dose-dependent. The strongest effect was seen with a mistletoe extract from mistletoe from P. Americana.

The team has carried out acute toxicity tests on the methanolic extracts and showed that at the efficacious doses all are in the non-toxic range. While mistletoe extracts are likely to be absorbed readily into the world of complementary medicine, further research is need to identify the active components. It is possible that researchers will discover these to be mistletoe absorbates or metabolites of natural products found in the host tree species.