LC characterisation of guaco medicinal extracts, Mikania laevigata and M. glomerata, and their effects on allergic pneumonitis.

The leaves of guaco (Mikania glomerata and M. laevigata) are widely used for the treatment of asthma and bronchitis. An LC method for the quantification of coumarin and O-coumaric acid in medicinal extracts was developed and validated for linearity, limit of detection, accuracy, precision, as well as intra- and inter-day variations. Extracts and isolated markers were tested in the mice allergic pneumonitis model and the histopathological profile of the lung tissue was analysed. The values found for coumarin and O-coumaric acid in a fluid extract were 1.53 and 1.69 mg/mL, respectively, for M. glomerata, and 0.96 and 0.38 mg/mL for M. laevigata. The values found for the lyophilised aqueous extract were 0.22 and 0.11 mg/mL of coumarin and O-coumaric acid in M. glomerata and 0.05 and 0.02 mg/mL in M. laevigata, respectively . The analysed samples from the species M. glomerata presented more coumarin and O-coumaric acid than the analogous M. laevigata species. Both coumarin and O-coumaric acid are part of the phytocomplex which is responsible for the therapeutic activity of the guaco species. The lyophilisation process generated some alterations in the extract, in comparison with the fresh aqueous extract, and these extracts did not present anti-inflammatory activity. Comparing the histopathological images of the groups tested, a haemorrhagic profile of lung tissue of animals treated with lyophilised extract, O-coumaric acid and coumarin is observed, but not for the group treated with hydroalcoholic extract. It is probable that some protective effect of the whole extract (lost during the lyophilisation process) blocks the harmful effects of the isolated markers.

Morphological characterization of the hemocytes of the pulmonate snail Biomphalaria tenagophila

The blood cells of the pulmonate snail Biomphalaria tenagophila, an important transmiter of the trematode Schistosoma mansoni in Brazil, were examined by ligth and transmission electron microscopy (TEM). Two hemocyte types were identified: hyalinocytes and granulocytes. Hyalinocytes are small young (immature), poorly spreading cells, which have a high nucleocytoplasmic ratio and are especially rich in free ribosomes. They do not appear to contain lysosome-like bodies and represent less than 10% of the circulating hemocytes. Granulocytes are larger hemocytes which readily spread on glass surface and which strongly react to the Gomori substrate, indicating the enzyme acid phosphatase usually found in lysosomes. Ultra-structurally, they contain a well-developed rough endoplasmic reticulum, dictyosomes and some some lysosome-like dense bodies. Granulocytes do not exhibit a characteristic granular aspect and the few granules observed in the cytoplasm should correspond to a lysosome system. They were named granulocytes instead of amoebocytes to use the same terminology adopted for Biomphalaria glabrata in order to make easier comparative studies. This is a preface study for more specific investigations on the functional activities of the blood cells of B. tenagophila and their interactions with the trematode parasite