ÚLTIMOS AVANCES EN LA QUÍMICA Y ACTIVIDADES BACTERIOLÓGICAS EN LAS PLANTAS MEDICINALES= Medicinal plants, last advances on chemistry and bacteria activities on the medicinal herbs

1) Exts. from Cecropia pachystachya (Cecropiaceae), a medicinal plant used in Brazil, were tested for their antimalarial activity against Plasmodium falciparum and/or Plasmodium berghei in mice.  The ethanol exts. of wood, root, and leaves reduce parasitemia of malaria-infected mice from 35-66% in relation to nontreated control mice.  The plant roots exts., with stronger activity, were further analyzed and provided subfractions also active in vivo from which two compds. were isolated and chem. characterized as -betasitosterol and tormentic acid.  Although both compds. were active in mice malaria, only the tormentic acid inhibited P. falciparum chloroquine-resistant parasites (W2) growth in cultures, reducing parasitemia dose-responsively (IC50=11-15 mg/mL).  The antimalarial activity of the plant exts. kept refrigerated 7 years after the initial isolation, when tested in parallel with new exts. freshly isolated from plants collected at the same geog. site, was similar, confirming the superiority of the plant roots and the stability of the active exts.  In these expts., inhibition of parasite growth was measured by hypoxanthine incorporation and by immunoenzymic assay (ELISA) with monoclonal antibodies against the P. falciparum histidine-rich protein (HRP2), expressed by the erythrocytic forms.  The plant roots showed the lowest IC50 value and displayed the lowest toxicity, thus having the best therapeutic index.  C. pachystachya species is therefore a good candidate for phytotherapeutic use against malaria.  Further studies are ongoing to isolate new active compds. through bioguided fractionation anal., in an effort to develop a new drug prototype against P. falciparum erythrocytic parasites.  Drug Dev Res 71: 82-91, 2010. Ó 2009 Wiley-Liss, Inc.

2) The dichloromethane ext. and pomolic acid (5) obtained from leaves of Cecropia pachystachya both reduced carrageenan-induced paw edema in mice.  Interestingly, while the triterpenoid inhibited the in vivo prodn. of interleukin-1beta by 39%, it had no effect on tumor necrosis factor-alpha prodn.  We also demonstrated that both the dichloromethane ext. and 5 inhibited the viability of human polymorphonuclear (PMN) cells in a time- and dose-dependent fashion.  The PMN membrane integrity was detd. with the aid of flow cytometry by means of the exclusion of propidium iodide as assay.  Although the cell membrane integrity was altered, neither the ext. nor 5 produced cellular necrosis.  Moreover, the development of hypodiploid nuclei and DNA fragmentation in the PMN cells were both dependent on dose and time.  Finally, in the annexin V-FITC binding assay, compd. 5 increased the total of apoptotic cells by 42% at 100 mM and by 71% at 200 mM with respect to the control group.  In conclusion, both the dichloromethane ext. of ambay and isolated compd. 5 inhibit the viability of PMN cells through apoptosis.  Since they can regulate human neutrophil functions in this way, it is likely that these substances can also limit inflammation.

3) Alzheimer disease (AD) is a neurodegenerative disease characterized by cognition impairment and personality changes.  Development of drugs for the treatment of cognitive deficits in AD has focused on agents which counteract the loss of cholinergic activities.  These symptoms of AD have been treated with some success by acetylcholinesterase (AchE) inhibitors (eg. galanthamine).  There is a great interest in finding better AchE inhibitors.  The Ellmann microplate assay and silica gel thin-layer chromatog. were used to screen exts. from plants as possible new sources of AchE inhibitors.  The plants were pulverized and extd. with hexane, chloroform, Et acetate, methanol, ethanol, water, lyophilized water, dichloromethane/methanol (1:1), aq. ethanol, hexane/chloroform (80%), dichloromethane/Et acetate (1:1), or essential oil.  The AchE inhibitory data are given for 28 plants species and their different parts examd.

Uses: heart, hypertension, impotence, do not remember, local pain, bronchitis, cough, inflammaion, kidney stone, diuretic.                                                 

Origin: Honduras, India, Mexico, Micronesia Federated States, New Guinea, Nicaragua, Panama, Paraguay, Peru, Pilippines, Southawesi, Sumatra, Suriname, United States, Uruguay, Venezuela.           

PARTE UTILIZADA= Used part: Hoja, corteza y brote.

ACCIÓN FARMACOLÓGICA= Pharmacological action: Expectorante, antiasmático.

COMPOSICIÓN QUÍMICA= Chemical composition: La corteza contiene cecropina y ácido tánico mientras que las hojas ambaína, ambainina, cecropina y cecropinina, ácidos araquídicos, behénico, lignocérico, cerótico, esteárico, margárico, nonadecanoico, heneicosanoico, tricosanoico, pentacosanoico; beta-sitosterol, stigma-4-en-3ona, alfa- y beta-amirina.

ZONA GEOGRÁFICA= Geografical zone: Argentina. 

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Parte utilizada
La droga está constituida por las hojas y brotes secos. En menor medida la corteza. A las hojas se les quitan los pecíolos y las nervaduras.

Farmacodinamia - Acciones farmacológicas
Acción sobre el aparato cardiovascular, Acción sobre el aparato respiratorio, Acción sobre el sistema nervioso, Efecto antioxidante, Actividad antimicrobiana, Actividad hipoglucemiante.

1) ALONSO, Jorge ; DESMARCHELIER, Cristian. Plantas medicinales autóctonas de la Argentina : bases científicas para su aplicación en atención primaria de la salud. Buenos Aires: L.O.L.A, 2005, p.48-53.

2) 270 (doscientos setenta) plantas medicinales iberoamericanas. Santiago de Bogotá : CYTED-SECAB, 1995, p.407-408.

3) UCHOA, Valdileia Teixeira, et al. Antimalarial activity of compounds and mixed fractions of Cecropia pachystachya.   Drug Development Research. 2010, vol.71, nº1, p.82-91.
 
4) SCHINELLA, Guillermo, et al. Anti-inflammatory and apoptotic activities of pomolic acid isolated from Cecropia pachystachya.  Planta Medica. 2008, vol.74, nº3, p.215-220.
 
5) SALLES, Trevisan, et al. Screening of plants with anticholinesterase activity for treatment of Alzheimer disease.  Quimica Nova. 2003, vol.26, nº3, p.301-304.

6) Plantas medicinales autóctonas de la Argentina. Bases científicas para su aplicación en atención primaria de la salud / Jorge Alonso y Cristian Jorge Desmarchelier. - 1a ed. - Ciudad Autónoma de Buenos Aires: Corpus Libros Médicos y Científicos, 2015.