No abstract

The interactions between carotenoids and membrane constituents are vital for understanding the mechanism of their dynamic action.

Purpose Carotenoids are potent natural antioxidants with many important applications. Their nanodispersion formulations can solve problems that may limit their usage. In this study, we produced carotenoid nanodispersions from extracted lutein (nano-Lut), extracted β-carotene (nano-EBc), and synthetic β-carotene (nano-SBC). Methods The present study has quantitatively emphasized the physicochemical, antioxidant, and cytotoxic properties of free and nanodispersed formulations of lutein and β-carotene. The nanodispersions were characterized by spectral absorption, dynamic light scattering, and zeta potential. Antioxidant and cytotoxicity assays were conducted for free and their nanodispersed forms. The cytotoxicity of free carotenoids and their nanodispersions was conducted on HSF, VERO, and BNL cell lines. Results Nano-Lut has the smallest mean particle size (185.2 ± 40.5 nm, PDI of 0.183 ± 0.01, and zeta potential of −28.6 ± 6.4 mV). Nano-SBc showed monomodal size distribution (220.5 ± 30.09 nm, PDI of 0.318 ± 0.03, and zeta potential of −12.1 ± 5.9 mV), while nano-EBc showed a bimodal size distribution (with a mean particle size of 498.3 ± 88.9 nm, PDI of 0.65 ± 0.08, and zeta potential of −39.7 ± 1.3 mV). All prepared nanodispersions showed less than 20% loss during the formulation process. Antioxidant assays showed that extracted lutein was the most active and synthetic β-carotene was the least. Cells showed higher tolerance for lutein and its nanodispersion than extracted or synthetic β-carotene either in free or nanodispersion forms. Conclusions The study proved that lutein in nanodispersed form possesses the smallest size, the highest antioxidant activity, and the lowest cytotoxicity among the tested formulations.

This work aims to evaluate cyclophosphamide (Cyclo) cytotoxic efficacy combined with liposomes in the presence or absence of beta carotene (beta) by detecting the effects of these compounds on the breast cancer cell line (MCF-7) DNA damage. The IC50 value for beta in cytotoxic assay with MCF-7 treated cells was 21.15 μg/ml, while with liposomal beta (LipoBeta) being 121 μg/ml. The free Cyclo IC50 value was 719.86 μg/ml, its liposomal form (LipoCyclo) was 172 μg/ml. The results indicated that in contrast with Cyclo and control values, all comet assay parameters for the LipoBeta were significantly increased (P < 0.05). In MCF-7 cells treated with beta, the findings show a higher intensity of comet tail than those treated with LipoBeta. The presence of several double-strand breaks suggests this high intensity relative to the head. The molecular combination between Cyclo and liposomes in the presence or absence of beta was characterized. Dynamic light scattering measurements confirmed the monodispersity of all samples. The incorporation of Cyclo or beta into liposomes exhibited a slight shift to higher temperature compared to the main peak of empty liposomes that exists at 101.5ºC which creates a conformational disorder within the phospholipids. The FTIR study showed structural alterations in vesicles after liposome encapsulation. Anti-Cancer Drugs 33: e462-e476