OBJECTIVE: The present study was aimed to synthesize and evaluate antimicrobial and anticancer activities of Schiff bases of 2-mercaptobenzimidazole.
METHODS: The Schiff bases of 2-mercaptobenzimidazole were synthesized from 4-(2-(1H-benzo[d]- imidazol-2-ylthio)acetamido)benzohydrazide. The synthesized compounds were evaluated for antimicrobial and anticancer activities by tube dilution method and Sulforhodamine-B (SRB) assay, respectively.
RESULTS: Compounds 8 (MICpa, an = 2.41, 1.20 µM/ml), 10 (MICse, sa = 2.50 µM/ml), 20 (MICec = 2.34 µM/ml) and 25 (MICca = 1.46 µM/ml) showed significant antimicrobial activity against tested bacterial and fungal strains and compounds 20 (IC50 = 8 µg/ml) and 23 (IC50 = 7 µg/ml) exhibited significant anticancer activity.
CONCLUSION: In general, the synthesized derivatives exhibited moderate antimicrobial and anticancer activities. Compounds 8 and 25 having high antifungal potential among the synthesized compounds may be taken as lead molecules for the development of novel antifungal agents.
METHODS: Isolation of compounds from G. segetum leaves was conducted using vacuum liquid chromatography (VLC) and column chromatography (CC). Two new compounds, namely 4,5,4'-trihydroxychalcone and 8,8'-(ethene-1,2-diyl)-dinaphtalene-1,4,5-triol, together with stigmasterol and β-sitosterol were isolated from G. segetum methanol extract and their structures were determined spectroscopically. The presence of gallic acid and rutin in the extract was determined quantitatively by a validated HPLC method. G. segetum methanol extract and its constituents were investigated for their effects on chemotaxis, phagocytosis, β2 integrin (CD18) expression, and reactive oxygen species (ROS) of polymorphonuclear leukocytes (PMNs), lymphocytes proliferation, cytokine release and nitric oxide (NO) production of phagocytes.
RESULTS: All the samples significantly inhibited all the innate immune responses tested except CD 18 expression on surface of leukocytes. Among the samples, 8,8'-(ethene-1,2-diyl)-dinaphtalene-1,4,5-triol exhibited the strongest inhibitory on chemotaxis, phagocytosis, ROS and NO production. The compound exhibited exceptionally strong inhibitions on ROS and chemotaxis activities with IC50 values lower than the positive controls, aspirin and ibuprofen, respectively. 4,5,4'-Trihydroxychalcone revealed the strongest immunosuppressive activity on proliferation of lymphocytes (IC50 value of 1.52 μM) and on release of IL-1β (IC50 value of 6.69 μM). Meanwhile rutin was the most potent sample against release of TNF-α from monocytes (IC50, 16.96 μM).
CONCLUSION: The extract showed strong immunosuppressive effects on various components of the immune system and these activities were possibly contributed mainly by 4,5,4'-trihydroxychalcone, 8,8'-(ethene-1,2-diyl)-dinaphtalene-1,4,5-triol and rutin.
AIM AND OBJECTIVES: In this study, we aim at investigating the mechanism of apoptosis by N-(4-chlorophenyl)-2-(4- (3,4,5-trimethoxybenzyloxy)benzoyl)-hydrazinecarbothioamide, a triazole precursor, henceforth termed compound P7a, in breast cancer cell line, MCF-7. We first screen a series of analogues containing (3,4,5-trimethoxybenzyloxy) phenyl moiety in breast cancer cell lines (MCF-7 and MDA-MB-231) to select the most cytotoxic compound and demonstrate a dose- and time-dependent cytotoxicity. Then, we unravel the mechanism of apoptosis of P7a in MCF-7 as well as its ability to cause cell cycle arrest.
METHODS: Synthesis was performed as previously described by Kareem and co-workers. Cytotoxicity of analogues containing (3,4,5-trimethoxybenzyloxy)phenyl moiety against MCF-7 and MDA-MB-231 cell lines was evaluated using the MTS assay. Flow cytometric analyses was done using Annexin V/PI staining, JC-1 staining and ROS assay. The activity of caspases using a chemoluminescence assay and western blot analysis was conducted to study the apoptotic pathway induced by the compound in MCF-7 cells. Lastly, cell cycle analysis was conducted using flow cytometry.
RESULTS: Upon 48 hours of treatment, compound P7a inhibited the proliferation of human breast cancer cells with IC50 values of 178.92 ± 12.51μM and 33.75 ± 1.20μM for MDA-MB-231 and MCF-7, respectively. Additionally, compound P7a showed selectivity towards the cancer cell line, MCF-7 compared to the normal breast cell line, hTERT-HME1, an advantage against current anticancer drugs (tamoxifen and vinblastine). Flow cytometric analyses using different assays indicated that compound P7a significantly increased the proportion of apoptotic cells, increased mitochondria membrane permeabilisation and caused generation of ROS in MCF-7. In addition, cell cycle analysis showed that cell proliferation was arrested at the G1 phase in the MCF-7 cell line. Furthermore, upon treatment, the MCF-7 cell line showed increased activity of caspase-3/7, and caspase-9. Lastly, the western blot analysis showed the up-regulation of pro-apoptotic proteins along with up-regulation of caspase-7 and caspase-9, indicating that an intrinsic pathway of apoptosis was induced.
CONCLUSION: The results suggest that compound P7a could be a potential chemotherapeutic agent for breast cancer.
MATERIALS AND METHODS: The in vivo toxicity (acute and subacute toxicity) study was carried out by oral administration of TQNLC and TQ to BALB/c mice. Animal survival, body weight, organ weight-to-body weight ratio, hematological profile, biochemistry profile, and histopathological changes were analyzed.
RESULTS: In acute toxicity, TQ that is loaded in nanostructured lipid carrier (NLC) was found to be less toxic than pure TQ. It can be concluded that encapsulation of TQ in lipid carrier minimizes the toxicity of the compound. In the subacute toxicity study, oral administration of 100 mg/kg of TQNLC and TQ did not cause mortality to either male or female but resulted in toxicity to the liver. It is postulated that long-term consumption of TQNLC and TQ may cause toxicity to the liver but not to the extent of altering the functions of the organ. For both treatments, the no observed adverse effect level (NOAEL) was found to be 10 mg/kg/d for mice in both sexes.
CONCLUSION: For long-term oral consumption, TQ and TQNLC at a dose of 10 mg/kg is safe in mice and does not exert any toxic effect. The results provide safety information of TQNLC, which would further help researchers in clinical use.