PURPOSE: The present study was designed to evaluate the anti-angiogenic and apoptosis induction properties of gramine through inhibiting TGF-β on DMBA induced oral squamous cell carcinoma (OSCC) in the hamster buccal pouch (HBP).
METHODS: The effects of gramine on TGF-β signalling in DMBA induced carcinogenic events such as angiogenesis and apoptosis were analysed by studying the mRNA expression using RT-PCR, protein expression by western blot and histopathological analysis using haematoxylin and eosin (H & E) staining.
RESULTS: Gramine significantly inhibited phosphorylation and nuclear translocation of Smad2 and Smad4 by blocking activity of the TGFβ-RII, RI and activation of inhibitory Smad7. Gramine inhibited angiogenic markers such as MMP-2, MMP-9, HIF-1α, VEGF, and VEGF-R2 as well as increased TIMP-2 expression. Furthermore, gramine induced apoptosis in DMBA induced tumour bearing animals by up regulating the pro apoptotic proteins Bax, cytochrome C, apaf-1, caspase-9 caspase-3 and PARP.
CONCLUSION: In this study, we clearly demonstrated that gramine treatment diminishes angiogenesis and induces apoptosis in hamster buccal pouch (HBP) carcinogenesis by modulating TGF-β signals.
MATERIAL AND METHOD: The purity of mitragynine in a Mitragyna speciosa alkaloid extract (MSAE) was determined using Ultra-Fast Liquid Chromatography (UFLC). In vitro high throughput ADMETox studies such as aqueous solubility, plasma protein binding, metabolic stability, permeability and cytotoxicity tests were carried out to analyze the physicochemical properties of MSAE and mitragynine. The UFLC quantification revealed that the purity of mitragynine in the MSAE was 40.9%.
RESULTS: MSAE and mitragynine are highly soluble in aqueous solution at pH 4.0 but less soluble at pH 7.4. A parallel artificial membrane permeability assay demonstrated that it is extensively absorbed through the semi-permeable membrane at pH 7.4 but very poorly at pH 4.0. Both are relatively highly bound to plasma proteins (> 85 % bound) and are metabolically stable to liver microsomes (> 84 % remained unchanged). In comparison to MSAE, mitragynine showed higher cytotoxicity against WRL 68, HepG2 and Clone 9 hepatocytes after 72 h treatment.
CONCLUSION: The obtained ADME and cytotoxicity data demonstrated that both MSAE and mitragynine have poor bioavailability and have the potential to be significantly cytotoxic.
MATERIALS AND METHODS: A total of 30 CF-1 albino mice obtained from the animal house of faculty of Medicine, Benghazi University, Benghazi, Libya were included in the study. These mice were fed with high cholesterol diet and divided into 2 groups. Twenty mice were administered piperine at a dose of 5mg/kg body weight. Piperine was isolated in Department of Pharmacognosy, Faculty of Pharmacy, Benghazi University, Benghazi and 10 mice were not administered piperine but fed with high fat diet. These mice were anesthetized with ketamine and halothane and blood was drawn from each mouse before the study and after three weeks by cardiocentesis. Serum transaminases (alanine aminotransferase [ALT] and aspartate aminotransferase [AST]), alkaline phosphatase and total protein were measured by authenticated methods.
RESULTS: Serum alanine amino transferase was significantly elevated (p=0.0002) in group A mice after the administration of Piperine extract for three weeks compared to those of group B mice. Serum aspartate amino transferase was elevated significantly (p=0.046) and alkaline phosphatase (p= 0.0001) also was significantly increased after the administration of piperine. Serum total protein (p= 0.011) values were significantly decreased after the use of piperine for three weeks in group A mice.
CONCLUSION: This study showed that there might have been a considerable damage to liver with piperine extract. Further research may be required to prove this damage to liver function.