ABSTRACT
Background/Aim. The use of herbal products as a supplement to minimize the effects of chemotherapy for cancer treatment requires further attention with respect to the activity and toxicity of chemotherapy. Uncaria tomentosa extract, which contains oxindole alkaloids, is one of these herbal products. The objective of this study was to evaluate whether Uncaria tomentosa extract modulates apoptosis induced by chemotherapy exposure. Materials and Methods. Colorectal adenocarcinoma cells (HT29 cells) were grown in the presence of oxaliplatin and/or Uncaria tomentosa extract. Results. The hydroalcoholic extract of Uncaria tomentosa enhanced chemotherapy-induced apoptosis, with an increase in the percentage of Annexin positive cells, an increase in caspase activities, and an increase of DNA fragments in culture of the neoplastic cells. Moreover, antioxidant activity may be related to apoptosis. Conclusion. Uncaria tomentosa extract has a role for cancer patients as a complementary therapy. Further studies evaluating these beneficial effects with other chemotherapy drugs are recommended.
ABSTRACT
INTRODUCTION: Uncaria tomentosa ("cat's claw") is widely used for the treatment of some infectious and inflammatory diseases. Oxindole alkaloids are regarded as the most important components responsible for the biological activities attributed to the plant. Their analysis require efficient sample preparation and suitable reference standards but few are commercially available. OBJECTIVE: To develop and validate a HPLC analytical method for oxindole alkaloids in Uncaria tomentosa with emphasis on sample preparation. METHOD: Factorial experimental designs were used for the optimisation of both sample preparation and chromatographic separation. The optimised sample preparation involved extraction with aqueous ethanol, and the granulometry of the powdered plant material significantly influenced extraction yields. Mitraphylline was used as a calibration reference for the determination of total alkaloids. RESULTS: The method was fully validated and showed good selectivity, linearity (r² ≥ 0.9996), accuracy (≥ 96%) and precision (RSD < 2.4%). Detection and quantification limits for mitraphylline were 0.8 and 2.4 ppm, respectively. CONCLUSION: The optimised chromatographic method, using organic buffer in the mobile phase, provided baseline separation of tetracyclic and pentacyclic alkaloids in the samples. Calibration using mitraphylline provided more accurate estimates of total alkaloid content when compared to other available reference alkaloids.
Subject(s)
Alkaloids/analysis , Cat's Claw/chemistry , Chromatography, High Pressure Liquid/methods , Indoles/analysis , Alkaloids/chemistry , Alkaloids/isolation & purification , Buffers , Calibration , Ethanol/chemistry , Hydrogen-Ion Concentration , Indole Alkaloids/analysis , Indole Alkaloids/chemistry , Indoles/chemistry , Indoles/isolation & purification , Molecular Structure , Oxindoles , Reproducibility of Results , Temperature , Time Factors , Water/chemistryABSTRACT
The aim of this study was to determine whether inclusion complexes between 2-hydroxypropyl-beta-cyclodextrin (HPbetaCD) and finasteride (FIN) are formed, and to characterize these. Equimolar FIN/HPbetaCD solid systems in the presence or absence of 0.1% (w/v) of polyvinylpyrrolidone K30 (PVP K30) or 0.3% of chitosan were prepared by coevaporation and freeze-drying methods. The systems were characterized by phase solubility, NMR, DSC, and XRD analysis. The results suggest that true binary and ternary inclusion complexes were formed.