Abstract New compounds with chemotherapeutic activity are sought after, and plants are an important source of these compounds. Four diterpenes, 19-deoxyicetexone, 7,20-dihydroanastomosine, icetexone and 19-deoxyisoicetexone, were isolated from the hexane-washed chloroform extract of Salvia ballotiflora. The cytotoxic activity of the hexane-washed chloroform extract and its four diterpenes were tested using the MTT assay against three tumor cell lines: HeLa (cervical cancer), A549 (lung cancer) and MCF7 (breast cancer), and two murine cell line: J774A.1 (epithelial cancer) and CT26 (colon cancer), and their IC50 values were determined. 19-Deoxyisoicetexone had the greatest effect on HeLa cells with IC50 of 3.2 µg/ml (9.36 µM), whereas hexane-washed chloroform extract had the best cytotoxic effect on A549 cells with an IC50 of 2.29 µg/ml. These effects of 19-deoxyisoicetexone and hexane-washed chloroform extract were with similar activity compared to cisplatin (IC50 = 1.06 µg/ml in HeLa cells, and 4.6 µg/ml (15.21 µM) in A549 cells).

Abstract Bioresorbable linear poly(ether-ester-urethane)s with different hydrophilic characteristics were synthesized from triblock copolymers of poly(ε-caprolactone)-poly(ethylene oxide)-poly(ε-caprolactone) (PCL-PEO) as macrodiols, and L-lysine diisocyanate (LDI) or hexamethylenediisocyanate (HDI) were used as the required diisocyanates. Macrodiols were obtained by ring-opening polymerization (ROP) of ε-caprolactone (CL). Polyurethanes were synthesized by the reaction of the triblock copolymers with LDI or HDI in solution using stannous 2-ethylhexanoate as catalyst. Polyurethane tablets were fabricated and investigated as prospective drug delivery systems. The effect of the PEO content on the polymers' performance as drug carriers was evaluated. It was found that water provoked more swelling and erosion of polymers with higher contents of PEO. The hydrocortisone release profiles were analyzed using the Ritger-Peppas approximation. An anomalous release behaviour (values of n higher than 0.5) was found for most of the analyzed samples.

Abstract: Recently, use of medicinal plants in Mexico and around the world has increased. However, in order to guarantee safe use of medicinal plants, it is necessary to quantify their content of heavy metals. In Mexico there is little information regarding content of toxic elements in medicinal plants, and these are consumed directly without a prior analysis of heavy metals. In this study, concentration of two toxic elements: cadmiom and lead (Cd and Pb) and a micronutrient (iron [Fe]) was quantified in three medicinal plants (Justicia spicigera, Arnica montana, and Hamelia pantens) collected from three different locations in two municipalities in the Huasteca Potosina, Mexico. Cd and Pb are two toxic elements with no biological function, and can cause severe damage when introduced into food chain, whereas iron is an essential element. However, iron is a major element that can form oxides and entrap trace elements such as Pb and Cd, and induce bioaccumulation of these elements in plants. Also, in the Huasteca Potosina, the three medicinal plants of this study are used for empirical treatment of iron deficiency. Therefore, it was important to study concentration of the three elements in these medicinal plants. Results of this analysis showed that 50% and 22% of herbal preparations contain higher contents of Cd and Pb than those considered as safe, respectively. In addition, the three medicinal plants could be an important source of Fe. Results suggest that collection of medicinal plants should be carried out in sites free of potentially dangerous toxic elements.

Resumen: Recientemente, el uso de plantas medicinales en México y en todo el mundo se ha incrementado. Sin embargo, con el fin de garantizar el uso seguro en de las plantas medicinales, es necesario cuantificar su contenido de metales pesados. En México existe poca información sobre el contenido de elementos tóxicos en las plantas medicinales, y estas son consumidas directamente sin realizar un análisis previo de metales pesados. En este estudio se cuantificó la concentración de dos elementos tóxicos: cadmio y plomo (Cd y Pb) y de un micronutriente: fierro (Fe), en tres plantas medicinales (Justicia spicigera, Arnica montana y Hamelia pantens) colectadas de tres sitios diferentes de dos municipios de la Huasteca Potosina, México. El Cd y Pb son dos elementos tóxicos sin ninguna función biológica conocida, que pueden causar severos daños al introducirse en la cadena alimenticia, mientras que el hierro es un elemento esencial. Sin embargo, el hierro es un elemento mayoritario que puede formar óxidos y atrapar elementos traza como el Pb y Cd, y favorecer la bioacumulación de estos elementos en las plantas. Además, en la Huasteca Potosina, las tres plantas medicinales en estudio son usadas para el tratamiento empírico en la deficiencia de hierro. Por lo anterior, fue importante estudiar la concentración de los tres elementos en ambas plantas medicinales. Los resultados de este análisis mostraron que el 50% y el 22% de los preparados de plantas medicinales contienen valores más altos que los considerados como seguros para Cd y Pb, respectivamente. Además, se confirma que estas tres plantas medicinales podrían ser una fuente importante de Fe. Con esto se sugiere que la recolección de plantas medicinales se debe realizar en sitios libres de elementos tóxicos potencialmente peligrosos.

Abstract Many medicinal herbs are used in folk medicine without taking into account their toxicity. Hamelia patens Jacq. (Rubiaceae), a Mexican endemic species, is used for the empirical treatment of pain. The aim of this work was to evaluate the toxicity and antinociceptive effects of ethanolic extracts of H. patens leaves. The toxicity of H. patens leaves (500–5000 mg/kg) was evaluated in acute (14 days) and subacute (28 days) assays. In the subacute assay, a blood analysis (both hematology and chemistry) was carried out. The antinociceptive effects of H. patens leaves (50–200 mg/kg) were evaluated using thermal-induced nociception (hot plate) and the chemical-induced nociceptive tests (acid acetic and formalin). In the acute toxicity test, the LD50 estimated for H. patens leaves was 2964 mg/kg i.p. and >5000 mg/kg p.o., whereas in the subacute test HPE did not affect hematological or biochemical parameters. In chemical-induced nociception models, H. patens (100 and 200 mg/kg p.o.) showed antinociceptive effects with similar activity than 100 mg/kg naproxen. In the hot plate test, HPE at 100 mg/kg (17%) and 200 mg/kg (25%) showed moderate antinociceptive effects. HPE could be a good source of antinociceptive agents because of its good activity and low toxicity.