Isolation of dihydrobenzofuran derivatives from ethnomedicinal species Polygonum barbatum as anticancer compounds

BACKGROUND: Ethnomedicinally, the family Polygonaceae is famous for the management of cancer. Various species of this family have been reported with anticancer potentials. This study was designed to isolate anticancer compounds from ethnomedicinally important species Polygonum barbatum. METHODS: The column chromatography was used for the isolation of compounds from the solvent fraction of P. barbatum. The characterization of isolated compounds was performed by various spectroscopic techniques like UV, IR, mass spectrometry and 1D-2D NMR spectroscopy. Keeping in view the ethnomedicinal importance of the family, genus and species of P barbatum, the isolated compounds (1-3) were screened for anticancer potentials against oral cancer (CAL-27) and lungs cancer (NCI H460) cell lines using MTT assay. Active compound was further investigated for apoptosis by using morphological changes and flow cytometry analysis. In vivo anti-angiogenic study of the isolated compounds was also carried using chorioallantoic membrane assay. Docking studies were carried out to explore the mechanism of anticancer activity. RESULTS: Three dihydrobenzofuran derivatives (1-3) have been isolated from the ethyl acetate fraction of P. barbatum. The structures of isolated compounds were elucidated as methyl (2S,3S)-2-(3,4-dimethoxyphenyl)-4-((E)-3-ethoxy-3-oxoprop-1-en-1-yl)-7-methoxy-2,3-dihydrobenzo-furan-3-carboxylate (1), (E)-3-((2S,3S)-2-(3,4-dimethoxyphenyl)-7-methoxy-3-(methoxy carbonyl)-2,3-dihydrobenzofuran-4-yl)acrylic acid (2) and (2S,3 S)-4-((E)-2-carboxyvinyl)-2-(3,4-dimethoxyphenyl)-7-hydroxy-2,3-dihydrobenzofuran-3-carboxylic acid (3). The compound 1 was found to be more potent with IC50 of 48.52 ± 0.95 and 53.24 ± 1.49 against oral cancer cells as compared to standard drug (IC50 = 97.76 ± 3.44 µM). Both compound also inhibited lung cancer cells but at higher concentrations. Morphological and flow cytometry analysis further confirms that compound 1 induces apoptosis after 24 to 48 h treatment. In antiangiogenesis assay, compounds 1, 2 and 3 exhibited IC50 values of 8.2 ± 1.1,13.4 ± 1.1 and 57.7 ± 0.3 µM respectively. The docking studies revealed that the compounds under study have the potential to target the DNA and thymidylate synthase (TS). CONCLUSION: Based on its overwhelming potency against the tested cell lines and in angiogenesis assay, compound 1 can be further evaluated mechanistically and can be developed as anticancer drug candidate.

Hepatic toxicity caused by PLGA-microspheres containing usnic acid from the lichen C ladonia substellata (AHTI) during pregnancy in Wistar rats

ABSTRACT This study aimed to evaluate the teratogenic and hepatotoxic potential of the usnic acid encapsulated into PLGA-microspheres. In total, 12 female Wistar rats in pregnancy were randomly distributed in the control group (n= 6) that received 1.0 mL of physiological solution and treatment group (n= 6) that received 25 mg/kg of encapsulated usnic acid by oral administration. All females were euthanized at day 20 of pregnancy and their fetuses were removed and analyzed. During the pregnancy was observed a reduction in weight gain. There was no difference in serum transaminases levels analyzed as well as any difference in liver weight in both groups. The histomorphometric analysis of the liver from the treatment group revealed an increase in number of hepatocytes and a decrease in nuclear area of these cells. Moreover, no alteration was observed in cell area of hepatocytes or number of Kupffer cells. The fetuses had an increase in total number of hepatocytes and a reduction in the amount of megakaryocytes. These results show the hepatotoxic potential of usnic acid during pregnancy. However, its toxicity can be minimized by encapsulation in microspheres.

Experimental benznidazole treatment of Trypanosoma cruzi II strains isolated from children of the Jequitinhonha Valley, Minas Gerais, Brazil, with Chagas disease

Trypanosoma cruzi strains from distinct geographic areas show differences in drug resistance and association between parasites genetic and treatment response has been observed. Considering that benznidazole (BZ) can reduce the parasite burden and tissues damage, even in not cured animals and individuals, the goal is to assess the drug response to BZ of T. cruzi II strains isolated from children of the Jequitinhonha Valley, state of Minas Gerais, Brazil, before treatment. Mice infected and treated with BZ in both phases of infection were compared with the untreated and evaluated by fresh blood examination, haemoculture, polymerase chain reaction, conventional (ELISA) and non-conventional (FC-ALTA) serologies. In mice treated in the acute phase, a significant decrease in parasitaemia was observed for all strains. Positive parasitological and/or serological tests in animals treated during the acute and chronic (95.1-100%) phases showed that most of the strains were BZ resistant. However, beneficial effect was demonstrated because significant reduction (p < 0.05%) and/or suppression of parasitaemia was observed in mice infected with all strains (acute phase), associated to reduction/elimination of inflammation and fibrosis for two/eight strains. BZ offered some benefit, even in not cured animals, what suggest that BZ use may be recommended at least for recent chronic infection of the studied region.

Derivatives of 3H-spiro1-benzofuran-2, 1’-cyclohexanes: immunostimulants for veterinary use / Derivados de 3H-espiro1-benzofurano-2, 1’-ciclohexanos: inmunoestimulantes de uso veterinario

Four 3H-spiro1-benzofuran-2, 1’-cyclohexanes were synthesized from filifolinol, two of which are reported for the first time. Docking molecular studies were carried out to determine in silico whether these derivatives have similar immunostimulant activity to that reported for filifolinol, and its oxidation product, filifolinone. Through of the study of interactions of these compounds with the heterodimer of the protein present in teleost TLR1-TLR2, filifolinol, 3’-filifolinchloride and filifolinyl acetate shows similar interactions between them, allowing to predict that they would have similar immunostimulant activity, but different to filifolinone and filifolinane or that they would act by a different mechanisms.

Cuatro 3H-spiro1-benzofuran-2, 1'-ciclohexanos se sintetizaron a partir de filifolinol, dos de los cuales son reportados por primera vez. Se llevaron a cabo estudios de docking molecular para determinar in silico si estos derivados tienen actividad inmunoestimulante similar a la reportada para filifolinol y su producto de oxidación, filifolinona. A través del estudio de las interacciones de estos compuestos con el heterodímero de la proteína presente en teleósteos TLR1-TLR2 se estableció que el filifolinol, 3'-cloruro de filifolinilo y acetato de filifolinilo tienen interacciones similares con el heterodímero, lo que permite predecir que entre ellos tendrían una actividad simi- lar, pero diferente a la de la filifolinona y filifolinano o que estos últimos actuarían por diferentes mecanismos.

Enzyme selectivity of new cyclooxygenase-2/5 lipoxygenase inhibitors using molecular modeling approach.

We have studied the conformational flexibility of three 5-keto-substituted 7-tert-butyl-2,3-dihydro-3,3-dimethylbenzofurans (DHDMBFs) which show dual cyclooxygenase (COX) and 5-lipoxygenase (LOX) inhibition and are potential candidates as antiinflammatory agents and analgesics. The conformations were studied by systematic search, molecular mechanics (MM) and simulated annealing molecular dynamics (SAMD) techniques. We also studied several structure based parameters and distribution of molecular electrostatic potential (MEP) around these molecules. All the three compounds were docked in the active cavity of cyclooxygenase-2 (COX-2) using graphical and energy grid search techniques. The complex geometries were optimized by MM. The results on conformational flexibility, inter-atomic distances and angles, MEP distribution and points of contacts with peptide side chains in active cavity have been used to understand the mechanistic cause of differential action of these molecules.

Colorimetric determination of D-Penicillamine in bulk form and in capsules using 4-Chloro-7-nitrobenzofuran

A simple and selective colorimetric method for the quantification of D-penicillamine in the presence of some penicillin preparations, common penicillin degradation products, EDTA and vitamin C is described. The method is based on the interaction between D-penicillamine in aqueous solution and 4-chloro-7-nitro-benzofurazan [NBD-C1], 0.1% w/v in methanol, in presence of 0.1 M borax solution. The developed colored product, after dilution with presence of 0.1 M borax solution. The developed colored product, after dilution with acetone, could be measured quantitatively at 612 nm. All variables were studied to optimize the reaction conditions. Regression analysis of Beer's plot showed good correlation [r=0.9990] in a general concentration range of 4-20 micro g ml-1 with a detection limit of 0.078, which represent the minimum absorbance value that can be measured. No interference could be observed from the presence of somepenicillins, penicillin degradation products and common pharmaceutical adjuvants. However, benzathine penicillin degradation and Vitamin cinterfere with analysis of the named drug by the proposed method. This method was applied successfully for the analysis of D-penicillamine in bulk from and in capsules. The results obtained are in good agreement with those obtained by the USP XXII method