METHODS: Rats were pre-treated orally with 2% Tween 80 (vehicle), 100 mg/kg ranitidine (reference drug) or MMMC (ratios of 1:1, 1:3 and 3:1 (v/v); doses of 15, 150 or 300 mg/kg) and then subjected to the ethanol-induced gastric ulcer or pyloric ligation assays. Stomach of rats from the former assay was collected and subjected to the macroscopic and microscopic observations, and enzymatic and non-enzymatic antioxidant studies while the gastric juice content and tissue from the latter assay were subjected to the antisecretory activity study. The UHPLC analysis of MMMC was also performed.
RESULT: MMMC, in the ratio 1:1, demonstrated the most effective (P gastric content but increased the gastric wall mucus content in the pyloric-ligation test. MMMC also demonstrated remarkable antioxidant activity indicated by the highest total phenolic content (TPC) value and oxygen radical absorbance capacity (ORAC) activity with the recorded IC50 value of approximately 53 μg/mL for the 2,2- diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. MMMC also improved the catalase (CAT), superoxide dismutase (SOD), glutathione (GSH), prostaglandin E2 (PGE2) and malondialdehyde (MDA) activities of the gastric tissue intoxicated by ethanol. UHPLC analysis of MMMC confirmed the presence several flavonoid-based bioactive compounds.
CONCLUSION: MMMC, at the ratio of 1:1 (v/v), exerts gastroprotective activity partly by activating its antisecretory and antioxidant activities, and via modulation of the gastric tissue endogenous antioxidant system.
OBJECTIVE: The present study was aimed to circumvent the pharmaceutical issues related to DsiRNA delivery to colon for the treatment of colorectal cancer.
METHOD: In this study, we have prepared water-soluble chitosan (WSC)-DsiRNA complex nanoparticles (NPs) by a simple complexation method and subsequently coated with pectin to protect DsiRNA from gastric milieu.
RESULTS: The mean particle size and zeta potential of the prepared WSC-DsiRNA complexes were varied from 145 ± 4 nm to 867 ± 81 nm and +38 ± 4 to -6.2 ± 2.7 mV respectively, when the concentrations of WSC (0.1%, 0.2% and 0.3% w/v) and pectin (0.1%, 0.2% and 0.25% w/v) were varied. The electron microscopic analysis revealed that morphology of WSC-DsiRNA complexes was varied from smooth spherical to irregular spherical. Cytotoxicity analysis demonstrated that viability of colorectal adenocarcinoma cell was decreased when the dose of WSC-DsiRNA was increased over the incubation from 24 to 48 h. A significantly low cumulative release of DsiRNA in simulated gastric (<15%) and intestinal fluids (<30%) and a marked increase in its release (>90%) in simulated colonic fluid (SCF) evidenced the feasibility and suitability of WSC-DsiRNA complexes for the colonic delivery.
CONCLUSION: These findings clearly indicated promising potential of WSC-DsiRNA complexes as a carrier to delivery DsiRNA to colon for the treatment of colorectal cancer.