RESUMO
Surface-enhanced Raman spectroscopy (SERS) is used to identify the biochemical changes associated with the antifungal activities of selenium and zinc organometallic complexes against Aspergillus niger fungus. These biochemical changes identified in the form of SERS peaks can help to understand the mechanism of action of these antifungal agents which is important for development of new antifungal drugs. The SERS spectral changes indicate the denaturation and conformational changes of proteins and fungal cell wall decomposition in complex exposed fungal samples. The SERS spectra of these organometallic complexes exposed fungi are analyzed by using statistical tools like principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA). PCA is employed to differentiate the SERS spectra of fungal samples exposed to ligands and complexes. The PLS-DA discriminated different groups of spectra with 99.8% sensitivity, 100% specificity, 98% accuracy and 86 % area under receiver operating characteristic (AUROC) curve.
Assuntos
Compostos Organometálicos , Selênio , Antifúngicos/farmacologia , Selênio/farmacologia , Zinco/farmacologia , Análise Espectral Raman/métodos , Análise Discriminante , Análise de Componente PrincipalRESUMO
OBJECTIVE: This study determines the efficacy and probable underlying mode of action to the folk usage of Euphorbia hirta, Fagonia indica and Capparis decidua in hypertension. METHODS: The aqueous-methanol extracts of E. hirta (EH.Cr), F. indica (FI.Cr) and C. decidua (CD.Cr) were tested for antihypertensive effects in rats using non-invasive and in-vasive blood pressure measuring apparatus. In-vitro assays were carried out using isolated rat aortae using PowerLab station. RESULTS: EH.Cr, FI.Cr and CD.Cr at 500 mg/kg (orally) caused a fall in the mean systolic blood pressure in arsenic-induced hypertensive and normotensive rats, similar to nifedipine. In rat aortae, EH.Cr, CD.Cr and FI.Cr reversed low (20 mM), high (80 mM) K+ and phenylephrine (P.E)-driven contractions, while F. indica partially inhibited high K+ contractions. In the presence of TEA, F. indica remained unable to relax low K+ contractions. EH.Cr and CD.Cr moved Ca++ concentrations response curves to the right, like nifedipine. All fractions of EH.Cr and CD.Cr except aqueous, pet-ether and chloroform fractions of FI.Cr displayed Ca++ antagonistic activity. FI.Cr, its ethyl acetate and aqueous fraction exhibited TEA-sensitive potassium channel activation. On baseline tension, test materials also produced phentolamine-sensitive vasospasm. CONCLUSION: E. hirta, F. indica and C. decidua possess antihypertensive activity in arsenic-induced hypertensive rats possibly mediated via endothelium-dependent vasorelaxation. In normotensive rats, E. hirta and C. decidua showed antihypertensive activities through endothelium-dependent and Ca++ antagonistic pathways, while F. indica exhibited potassium channel activation and Ca++ antagonistic like effects in its vasorelaxation. Additional weaker vasospastic effects were derived through α-adrenergic like pathways.
RESUMO
This study elicits the underlying mechanism(s) of Capparis decidua when used for different gut disorders. HPLC chromatogram of C. decidua extract (CD.Cr) and its respective fractions showed a variety of phytochemicals of which, kaempferol being in a high proportion. In mice, CD.Cr at doses of 70 and 150 mg/kg enhanced the wet feces output to 33 and 44% respectively as compared to carbachol (47.6%), while doses of 500 and 700 mg/kg, presented 41 and 70% safety against castor oil-driven diarrhea, respectively. Its flavonoid constituent, kaempferol at doses of (50 and 100 mg/kg) produced 51.7 and 82% safety when compared to nifedipine which provided 95% safety at dose of 40 mg/kg against castor oil-driven diarrhea like loperamide. In isolated jejunum preparations, C. decidua extract and its respective fractions (except pet-ether) produced atropine-sensitive inhibitory effects, whereas kaempferol and nifedipine showed atropine insensitive effects. Against high K+-induced contractions, C. decidua's fractions and kaempferol both exhibited a concentration-related non-specific inhibition while displacing the Ca++ -CRCs to right-ward with suppression in maximal response like nifedipine. In isolated rat ileal preparations, CD.Cr and respective fractions elicited atropine-sensitive gut excitatory responses. In summary, this article reports C. decidua's laxative effect through cholinergic receptor activation as well as its antidiarrheal effects, where its flavonoid constituent kaempferol produces Ca++ antagonist like activity, thus justifying C. decidua folk use in constipation and diarrhea.
Assuntos
Antidiarreicos/uso terapêutico , Capparis , Diarreia/tratamento farmacológico , Flavonoides/uso terapêutico , Jejuno/efeitos dos fármacos , Compostos Fitoquímicos/uso terapêutico , Animais , Antidiarreicos/isolamento & purificação , Antidiarreicos/farmacologia , Diarreia/induzido quimicamente , Feminino , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Jejuno/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Técnicas de Cultura de Órgãos , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley , RoedoresRESUMO
BACKGROUND: Euphorbia hirta (Linn) family Euphorbiaceae has been used in indigenous system of medicine for the treatment of gastrointestinal disorders. This study was designed to determine the pharmacological basis for the medicinal use of E. hirta in diarrhea and constipation. METHODS: The aqueous-methanol extract of whole herb of E. hirta (EH.Cr) and its petroleum ether (Pet.EH), chloroform (CHCl3.EH), ethyl acetate (Et.Ac.EH) and aqueous (Aq.EH) fractions were tested in the in-vivo experiments using Balb/c mice, while the in-vitro studies were performed on isolated jejunum and ileum preparations of locally bred rabbit and Sprague Dawley rats, respectively, using PowerLab data system. RESULTS: Qualitative phytochemical analysis showed the presence of alkaloids, saponins, flavonoids, tannins, phenols, cardiac glycosides, while HPLC of EH.Cr showed quercetin in high proportion. In mice, EH.Cr at the dose of 500 and 1000 mg/kg showed 41 and 70% protection from castor oil-induced diarrhea, respectively, similar to the effect of quercetin and loperamide, while at lower doses (50 and 100 mg/kg), it caused an increase in the fecal output. In loperamide-induced constipated mice, EH.Cr also displayed laxative effect with respective values of 28.6 and 35.3% at 50 and 100 mg/kg. In rabbit jejunum, EH.Cr showed atropine-sensitive inhibitory effect in a concentration-dependent manner, while quercetin and nifedipine exhibited atropine-insensitive effects. Fractions of E. hirta also produced atropine-sensitive inhibitory effects except Pet.EH and CHCl3.EH. On high (80 mM) and low (20 mM) K+ - induced contractions, the crude extract and fractions exhibited a concentration-dependent non-specific inhibition of both spasmogens and displaced concentration-response curves of Ca++ to the right with suppression of the maximum effect similar to the effect quercetin and nifedipine. Fractions showed wide distribution of spasmolytic and Ca++ antagonist like effects. In rat ileum, EH.Cr and its fractions exhibited atropine-sensitive gut stimulant effects except Pet.EH. CONCLUSION: The crude extract of E. hirta possesses antidiarrheal effect possibly mediated through Ca++ antagonist like gut inhibitory constituents, while its laxative effect was mediated primarily through muscarinic receptor agonist like gut stimulant constituents. Thus, these findings provide an evidence to the folkloric use of E. hirta in diarrhea and constipation.