In vitro exposure to pumpkin extract induces a protective transcriptomic profile in blood brain barrier electron transport chain

ABSTRACT

C. maxima (var. Delica) is a variety of pumpkin known for its beneficial effects and its high content in carotenoids (violaxanthin, astaxanthin, antheraxanthin, zeaxanthin, lutein, lycopene and β-carotene), which are natural antioxidants bioavailable to humans through food consumption. Numerous biological effects have been attributed to carotenoids due to their antioxidant activity: improved immune response, anti-inflammatory and anti-tumor properties and reduced risk of cardiovascular and chronic degenerative diseases. They are capable of accumulating in the brain after crossing the blood-brain barrier. Therefore, the aim of this study is to analyze changes in mitochondrial gene expression using an in vitro cell model (ECV304) of the blood brain barrier, after exposure to pumpkin extract. Cells were treated during 24 h at 5 different β-carotene concentrations, as reference extract compound: 1.72×10-4 – 1.72×10-3– 1.72×10-2 – 0.172 – 1.72 nM in DMSO 0.5%. The extracted RNA was used to perform qPCR analysis on 15 mitochondrial related genes: MT-ND2, MT-ND3, MT-ND4, MT-ND4L, MT-ND5, MT-CO1, MT-CO3, MT-ATP6, MT-ATP8, MT-RNR2, MRPL12, OSGIN1, SRXN1, TXNIP, UCP2, and S18 as reference gene. Results demonstrate that dietary carotenoids act at transcriptional level, especially on the genes belonging to the electron transport chain, reporting an overall protective pattern. The findings show a dose dependent differential gene expression pattern by carotenoids exposure, even at low concentrations. (AU)