Biology subjects

Andreu, A. B.

Publications and source records attributed to Andreu, A. B..

3 recordsLinked to original sources

bioRxiv2023

Red-purple Andean potato polyphenols have an anti-neuroblastoma effect in vitro via apoptosis through mitochondria.

Andean potatoes (Solanum tuberosum ssp. andigena) are a good source of dietary polyphenols, such as phenolic acid and flavonoids. These polyphenols have several beneficial effects on human health due to their antioxidant properties. Previously, we demonstrated that polyphenol extracts from Andean potato tubers exerted a concentration-dependent cytotoxic effect in human neuroblastoma cells. However, the mechanisms involved in this cytotoxic activity were not explored. Here we show that Santa Maria tubers polyphenols activated a programmed cell death by caspase-independent apoptosis. We found that polyphenols induced cell and nucleus morphology changes and slightly affected the cell cycle. Furthermore, the polyphenols altered the neuroblastoma cells homeostasis redox and mitochondrial function, increasing the levels of apoptotic cells. Finally, we showed that neither Bcl-2 nor caspase-3 was involved in this mechanism of death. Our results confirmed that Santa Maria tubers polyphenols are bioactive compounds with mitochondria as a target and contribute to revalorizing Andean potatoes as a functional food. These findings demonstrated that they would be a good source of anti-tumor compounds that would induce tumor cell death even in apoptotic-resistant tumors, opening new therapeutic avenues.

cancer biology↗

bioRxiv2022

Metabolite profiling and cytotoxic activity of Andean potatoes: polyamines and glycoalkaloids as potential anticancer agents in human neuroblastoma cells in vitro

Andean potatoes (Solanum tuberosum L. ssp. andigena) are a good source of dietary antioxidant polyphenols. We have previously demonstrated that polyphenol extracts from Andean potato tubers exerted a dose-dependent cytotoxic effect in human neuroblastoma SH-SY5Y cells, being skin extracts more potent than flesh ones. In order to gain insight into the bioactivities of potato phenolics, we investigated the composition and the in vitro cytotoxic activity of total extracts and fractions of skin and flesh tubers of three Andean potato cultivars (Santa Maria, Waicha, and Moradita). Potato total extracts were subjected to liquid-liquid fractionation using ethyl acetate solvent in organic and aqueous fractions. We analyzed both fractions by HPLC-DAD, HPLC-ESI-MS/MS, and HPLC-HRMS. Results corroborated the expected composition of each fraction. Organic fractions were rich in hydroxycinnamic acids (principally chlorogenic acid isomers), whereas aqueous fractions contained mainly polyamines conjugated with phenolic acids, glycoalkaloids, and flavonoids. Organic fractions were not cytotoxic against SH-SY5Y cells, and indeed, some increased cellular metabolism compared to controls. Aqueous fractions were cytotoxic and even more potent than their respective total extracts. Treatment with a combination of both fractions showed a similar cytotoxic response to the corresponding extract. According to correlation studies, it is tempting to speculate that polyamines and glycoalkaloids are crucial in inducing cell death. Our findings indicate that the activity of Andean potato extracts is a combination of various compounds and contribute to the revalorization of potato as a functional food.

cell biology↗

bioRxiv2021

Identification of the functions of 4-coumarate-CoA ligase/ acyl-CoA synthetase paralogs in potato

Hydroxycinnamates, intermediates of phenylpropanoid metabolism, can be converted by Class I and Class II 4-coumarate:CoA ligases (4CL) to their activated CoA esters. Class I enzymes are involved in suberin/lignin deposition, whereas Class II enzymes feed flavonoid biosynthesis. Before initiating transcript analysis in Andean potato tubers, we undertook a thorough classification of the 4CL/ACS superfamily to settle a confusing and inconsistent description of the family in literature. Phylogenetic analysis and clustering of sequences from SwissProt and 15 plant species resolved the cytosolic Class I 4CL, Class II 4CL and ACOS5 subfamilies, as well as the peroxisomal subfamilies of Class III 4CL, OPC-8:0-CoA ligase (OPCL) and Uncharacterised ACS I, II and III. Analysis shows that the ACOS5 family, which has oleate as substrate, has a rather different binding pocket. Class III enzymes, which feed ubiquinone biosynthesis, and OPCL enzymes, involved in jasmonic acid biosynthesis, have binding pockets similar to those of cytosolic 4CL enzymes. Differences between Class I and II suggest that CoA governs flux regulation, and that hydroxycinnamate substrate specificity likely did not constrain their evolution. Notably, using sequences from 200 additional plant species, we show most eudicots possess two and most Poaceae three functionally non-redundant Class I homologues, suggesting that substrate specificity did constrain the evolution of the Class I subfamilies. Finally, we show that Class I and Class II transcript regulation corresponds to the proposed classification and may reflect Class I diversification constrained by different requirements for suberin and lignin deposition in native and wounded potato tuber periderm.

plant biology↗