OBJECTIVE: The present work aimed to evaluate their cytotoxicity against HepG2 (hepatocellular carcinoma), A549 (pulmonary adenocarcinoma), MCF-7 (breast adenocarcinoma) and WRL 68 (embryonic liver) cell lines.
METHODS: MTT assay was employed to investigate the cytotoxicity, and a tyrosinase inhibitor screening kit was used to evaluate the Tyrosinase (TYR) inhibitory activity of the targets.
RESULTS: The tested compounds exhibited no considerable cytotoxicity, and nine of them were selected for a tyrosinase inhibitory test. Compounds 2b, 2m, and 5a showed good inhibitory percentages against TYR compared to that of kojic acid (reference substance). Molecular docking was performed to rationalize the Structure-Activity Relationship (SAR) of the target pyridotriazolopyrimidines and analyze the binding between the docked-selected compounds and the amino acid residues in the active site of tyrosinase.
CONCLUSION: The target pyridotriazolopyrimidines were identified as a new class of tyrosinase inhibitors.
Materials and Methods: Dried root of P. glabra was extracted under reflux with methyl alcohol, fractionated through the vacuum liquid chromatography technique, and evaporated and then purified the compounds using column chromatography and preparative thin-layer chromatography. THP-1 cells were treated with amentoflavone, 5,7,4'-hydroxyflavonoid, and stigmasterol with various concentrations (0-30 µg/mL) and then incubated with MTS reagent for 2h. Treatment was done for 24, 48, and 72h. Then, effects of these compounds were also tested on PGE2, TNF-α, and IL-6 expression in human THP-1-derived macrophage cells for 24h.
Results: Three new compounds such as amentoflavone, 5,7,4'-hydroxyflavonoid, and stigmasterol were isolated. After 24h of incubation, a significant decrease in cell viability was reported with IC50 values of amentoflavone, 5,7,4'- hydroxyflavonoid, and stigmasterol (21 µg/mL ≡ 38 M), (18 µg/mL ≡ 66 M) and (20 µg/mL ≡ 48.5 M), respectively. Whereas for 48 and 72h treatment showed a less decreased cell viability compared with 24h treatment. These compounds also showed a significant reduction in the production of TNF-α, IL-6, and PGE2 in a dose-dependent manner.
Conclusions: The isolated new compounds showed significant cytotoxicity and anti-inflammatory effects.
METHODS: We studied the health of 636 OA from seven sub-tribes in the Peninsular. Parameters that were assessed included height, weight, BMI and waist circumference whilst blood pressure, cholesterols, fasting blood glucose and HbA1c levels were recorded. We then analysed cardio-metabolic risk factor prevalences and performed multiple pair-wise comparisons among different sub-tribes and socio-economic clusters.
RESULTS: Cardio-metabolic risk factors were recorded in the seven sub-tribes.. Prevalence for general and abdominal obesity were highest in the urbanized Orang Seletar (31 · 6 ± 5 · 7%; 66 · 1 ± 5 · 9%). Notably, hunter gatherer Jehai and Batek tribes displayed the highest prevalence for hypertension (43 · 8 ± 9 · 29% and 51 · 2 ± 15 · 3%) despite being the leanest and most remote, while the Mendriq sub-tribe, living in the same jungle area with access to similar resources as the Batek were less hypertensive (16.3 ± 11.0%), but displayed higher prevalence of abdominal obesity (27.30 ± 13.16%).
CONCLUSIONS: We describe the cardio-metabolic risk factors of seven indigenous communities in Malaysia. We report variable prevalence of obesity, cholesterol, hypertension and diabetes in the OA in contrast to the larger ethnic majorities such as Malays, Chinese and Indians in Malaysia These differences are likely to be due to socio-economic effects and lifestyle changes. In some sub-tribes, other factors including genetic predisposition may also play a role. It is expected that the cardio-metabolic risk factors may worsen with further urbanization, increase the health burden of these communities and strain the government's resources.