The bioguided fractionation and pharmacological activity of an endemic Salix canariensis species.

The present study was designed to confirm the wide traditional use of treating pain with Salix canariensis, an endemic species of the Macaronesian region. The active compounds were identified. Pharmacological activities were explored in experimental animals by acetic acid-induced writhing, formalin and Levy's tests, and bioactive compounds were identified after a bio-guided fractionation of the most active organic extract. S. canariensis extract, orally administrated at different doses, led to a significant reduction in writhing, caused a moderate decrease of formalin-induced pain and revealed an excellent dose-dependent anti-inflammatory effect. Bioassay-guided fractionation of the ethyl acetate extract suggested the possible presence of pentacyclic triterpenes from oleanane and ursane series. These findings allow the conclusion that S. canariensis exerts analgesic and anti-inflammatory activities, documenting its traditional use in the treatment of pain and inflammatory diseases.

Antinociceptive and anti-inflammatory activity of Sambucus palmensis link, an endemic Canary Island species.

ETHNOPHARMACOLOGICAL RELEVANCE: Sambucus palmensis Link is an endemic species of the Canary Islands, popularly known as "Saúco canario". This species has wide use in folk medicine practice on the islands, especially as analgesic and anti-inflammatory. So the aim of our study is to evaluate the antinociceptive and anti-inflammatory activity of an aqueous extract of this species. MATERIALS AND METHODS: Three aqueous extract doses (35, 52.5 and 70 mg/kg) were orally administered to laboratory Swiss mice obtained from the Central Animal House of La Laguna University. Writhing responses induced by phenylquinone, formalin induced paw pain response, tail-flick test and paw edema induced by carrageenan were evaluated in this work. RESULTS: Oral pretreatment with 52.5 and 70 mg/kg Sambucus palmensis aqueous extract significantly reduced the writhing number induced by phenylquinone injection (61.64 and 89.04% respectively), and the pain response in the first (36.67 and 38.89%) and second (57.28 and 70.1%) phases respectively of the formalin test. Sambucus palmensis had a very slight effect on tail-flick test and inhibited moderately the edema formation induced by carrageenan in mice. CONCLUSIONS: These data show for the first time that Sambucus palmensis has a significant antinociceptive effect that seems to be more peripherical than central. Sambucus palmensis also displays a moderate anti-inflammatory activity in an acute inflammation model. These results support the widespread use of Sambucus palmensis in popular medicine to treat pain and inflammation.

Electrical conductivity measurements of urine as a new simplified method to evaluate the diuretic activity of medicinal plants.

ETHNOPHARMACOLOGICAL RELEVANCE: Diuretic plants are widely used in traditional medicine in many countries. However, many of these species have not been subjected to experimental studies to confirm that property. In this paper, a simple new method is proposed to evaluate the diuretic activity of plants. We define a new index that takes into account only the volume of urinary excretion and total ion concentration excreted obtained by specific electrical conductivity measurements. MATERIALS AND METHODS: Urine was collected in a graduate cylinder during the 8h after Artemisia thuscula (AT), Withania aristata (WA), Smilax canariensis (SC) and HCTZ oral administration to laboratory mice. To obtain the new index Diuretic Power (DP), we measured the specific electrical conductivity (κ) of the fresh urine samples. We calculated the concentration of a NaCl (or KCl) aqueous solution that has the same specific electrical conductivity as the urine sample. We multiplied this concentration by the corresponding urinary excretion volume, thus obtaining the total mEq. of electrolyte excreted "as if all were NaCl (or KCl)". Finally, we divided these mEq. by those corresponding to the control to obtain the DP value. RESULTS: HCTZ showed a 40% increase in DP, with respect to the control group, independently of the doses used, and the studied plants produced an increase between 7 and 28%. DP values were compared with other common indexes, DI and SIi, showing that the variation sequence of the three indexes was the same for HCTZ, WA and SC. CONCLUSIONS: A new and easy index, that we called diuretic power (DP), for estimating the diuretic activity of drugs or plants is proposed. It allows us to highlight diuretic effect with respect to a control value of a large amount of drugs or plants that had not been previously experimentally studied.