RESUMO
This study evaluated the cytotoxic activity of Tamoxifen (TMX), an anti-estrogen drug, with microalgal crude extracts (MCEs) in single and synergistic application (TMX-MCEs) on MCF-7 and 4T1 breast cancer cells, and non-cancerous Vero cells. The MCEs of Nannochloropsis oculata, Tetraselmis suecica and Chlorella sp. from five different solvents (methanol, MET; ethanol, ETH; water, W; chloroform, CHL; and hexane, HEX) were developed. The TMX-MCEs-ETH and W at the 1:2 and 1:3 ratios, attained IC50 of 15.84-29.51 µg/mL against MCF-7; 13.8-31.62 µg/mL against 4T1; and 24.54-85.11 µg/mL against Vero cells. Higher late apoptosis was exhibited against MCF-7 by the TMX-N. oculata-ETH (41.15 %); and by the TMX-T. suecica-ETH (65.69 %) against 4T1 cells. The TMX-T. suecica-ETH also showed higher ADP/ATP ratios, but comparable Caspase activities to control. For Vero cells, overall apoptotic effects were lowered with synergistic application, and only early apoptosis was higher with TMX-T. suecica-ETH but at lower levels (29.84 %). The MCEs-W showed the presence of alanine, oleic acid, linoleic acid, lactic acid, and fumaric acid. Based on Principal Component Analysis (PCA), the spectral signals for polar solvents such as MET and ETH, were found in the same cluster, while the non-polar solvent CHL was with HEX, suggesting similar chemical profiles clustered for the same polarity. The CHL and HEX were more effective with N. oculata and T. suecica which were of the marine origin, while the ETH and MET were more effective with Chlorella sp., which was of the freshwater origin. The synergistic application of microalgal bioactive compounds with TMX can maintain the cytotoxicity against breast cancer cells whilst reducing the toxicity against non-cancerous Vero cells. These findings will benefit the biopharmaceutical, and functional and healthy food industries.
RESUMO
Pandanus tectorius fruit, a natural product rich in tangeretin and ethyl caffeate, has been reported to have potential as anti-hypercholesterolemia agent via Scavenger Receptor Class B type 1 (SR-B1) pathway. However, due to its semi-polar properties, P. tectorius extract exhibits poor solubility when used as a medical remedy. The extract's solubility can potentially be improved through a synthesis of nanoparticles of chitosan-P. tectorius fruit extract. This can also increase the extract's SR-B1 gene expression activity. To date, no studies of nanoparticles of chitosan-P. tectorius fruit extract and its pathway via SR-B1 have been published anywhere. In this study, cytotoxicity properties against HepG2 were explored by MTT. Then luciferase assay was used to detect their effectiveness in increasing SR-B1 activity. An in vivo study using Sprague dawley was carried out to observe the extract nanoparticles' effectiveness in reducing the cholesterol levels and the toxicity property in rat's liver. As the results showed, the extract nanoparticles had no cytotoxic activity against HepG2 cells and exhibited higher SR-B1 gene expression activity than the non-nanoparticle form. As the in vivo study proved, nanoparticle treatment can reduce the levels of TC (197%), LDL (360%), and TG (109%), as well as increase the level of HDL cholesterol by 150%, in comparison to those for the untreated high-cholesterol diet group. From the toxicity study, it was found that there was non-toxicity in the liver. It can be concluded that nanoparticles of chitosan-P. tectorius fruit extract successfully increased P. tectorius fruit extract's effectiveness in reducing hypercholesterolemia via SR-B1 pathway. Hence, it can be suggested that nanoparticles of chitosan-P. tectorius fruit extract is safe and suitable as an alternative treatment for controlling hypercholesterolemia via SR-B1 pathway.