Asociación entre los niveles elevados de ácidos biliares y cáncer digestivo / Association between high bile acid levels and digestive cancer

Introducción: Los ácidos biliares en condiciones no fisiológicas se consideran agentes inflamatorio-carcinógenos endógenos que originan alteraciones en membranas plasmáticas, mitocondrias, el ADN, los genes y, la apoptosis de las células epiteliales. Objetivo: Describir la asociación entre los niveles elevados de ácidos biliares en la luz intestinal y la secuencia inflamación-cáncer, expresados como lesiones inflamatorias, premalignas y malignas del tracto digestivo. Métodos: Revisión sistemática y crítica de las evidencias sobre los mecanismos biomoleculares asociados a niveles altos de ácidos biliares en la luz intestinal y la secuencia inflamación-carcinogénesis, en bases de datos como PubMed, Medline, SciELO, LILACS y Elsevier, publicados entre 2015-2020, que establecen el fundamento teórico y metabolómico de dicha secuencia. Resultados: Los ácidos biliares tienen una acción tóxica en la secuencia inflamación-cáncer del tracto digestivo, al perderse el control de su homeostasis o la integridad anatomo-funcional del sistema hepato-vesículo-bilio-intestinal. Conclusiones: Los mecanismos celulares y biomoleculares desencadenados por los niveles altos de ácidos biliares contextualizan la génesis del proceso secuencial inflamación-cáncer y su interacción con los factores de riesgo clásicos, genéticos y epigenéticos reconocidos como un nuevo paradigma fisiopatológico del cáncer digestivo(AU)

Introduction: In non-physiological conditions, bile acids (BA) are considered to be endogenous inflammatory-carcinogenic agents causing alterations in plasma membranes, mitochondria, DNA, genes and epithelial cell apoptosis. Objective: Describe the association between high bile acid levels in the intestinal lumen and the inflammation-cancer sequence, expressed as inflammatory premalignant and malignant lesions of the digestive tract. Methods: A systematic critical review was conducted of the evidence about biomolecular mechanisms associated to high bile acid levels in the intestinal lumen and the inflammation-carcinogenesis sequence published in the databases PubMed, Medline, SciELO, LILACS and Elsevier in the period 2015-2020, laying the theoretical and metabolomic foundations of that sequence. Results: Bile acids display toxic activity in the inflammation-cancer sequence of the digestive tract, since control is lost of its homeostasis or the anatomical-functional integrity of the hepato-vesicular-biliary-intestinal system. Conclusions: The cellular and biomolecular mechanisms triggered by high bile acid levels provide a context for the genesis of the inflammation-cancer sequential process and its interaction with the classic, genetic and epigenetic risk factors recognized as a new pathophysiological paradigm of digestive cancer(AU)

Actividad biológica y toxicológica de los ácidos biliares en la actualidad / Biological and toxicological activity of bile acids today

Introducción: los ácidos biliares no solo tienen como actividad biológica regular la absorción de vitaminas liposolubles, colesterol y lípidos, sino actúan también como moléculas de señalización, moduladores de la proliferación celular intestinal, de la expresión de genes y del metabolismo energético según estudios in vitro e in vivo; en condiciones fisiológicas mantienen su homeostasis, que al ser interrumpida promueve suacción toxicológica. Objetivo: describir la actualidad de los nuevos conocimientos sobre la actividad biológica y toxicológica de los ácidos biliares en el aparato digestivo, dirigido a cirujanos generales, gastroenterólogos, clínicos y fisiólogos que les permitan contextualizar el proceso inflamación-carcinogénesis relacionado con los efectos toxicológicos de los ácidos biliares. Método: se realizó una revisión sistemática de la actividad biológica y toxicológica de los ácidos biliares para los cirujanos generales, gastroenterólogos, clínicos y fisiólogos, como herramienta útil en la compresión fisiopatológico del metabolismo de los ácidos biliares. Conclusión: los ácidos biliares desempeñan una función clave como moléculas de señalización en la modulación de la proliferación de células epiteliales, la expresión de genes y el metabolismo energético, que cuando se interrumpe su homeostasis se promueve la acción tóxica de estos, lo que se traduce en el proceso inflamación-carcinogénesis digestiva(AU)

Introduction: bile acids not only have as a regular biological activity the absorption of fat-soluble vitamins, cholesterol and lipids, but also act as signaling molecules, modulators of intestinal cell proliferation, gene expression and energy metabolism according to in vitro studies and in vivo; under physiological conditions they maintain their homeostasis, which when interrupted promotes their toxicological action. Objective: to describe the news of the new knowledge about the biological and toxicological activity of bile acids in the digestive system, aimed at general surgeons, gastroenterologists, clinicians and physiologists that allow them to contextualize the inflammation-carcinogenesis process related to the toxicological effects of bile acids. Method: A systematic review of the biological and toxicological activity of bile acids was performed for general surgeons, gastroenterologists, clinicians and physiologists, as a useful tool in the pathophysiological compression of bile acid metabolism. Conclusion: bile acids play a key role as signaling molecules in the modulation of epithelial cell proliferation, gene expression and energy metabolism, which when their homeostasis is interrupted, their toxic action is promoted, which translates in the inflammation-digestive carcinogenesis process(AU)

Secondary bile acids effects in colon pathology. Experimental mice study

ABSTRACTPURPOSE:To assess whether deoxycholic acid (DOC) and lithocholic acid (LCA) administered in a period of six months in a concentration of 0.25% may have a carcinogenic role in mice colon.METHODS:The study used C57BL6 female mice divided into four groups. The control group received a balanced diet and the others received diets supplemented with 0.25% DOC, 0.25% LCA and 0.125% DOC+0.125% LCA, respectively. After euthanasia, the lesions found in the resected gastrointestinal tracts were stained with hematoxylin-eosin and examined microscopically.RESULTS:No gastrointestinal tract changes were observed in the control group, while hyperplastic Peyer's patches in the small intestine, flat adenomas with mild dysplasia and chronic colitis at the level of the colon were found in all three test groups. The colonic lesions prevailed in the proximal colon. The highest number of flat adenoma lesions (8), hyperplasia of Peyer's patches (25) and chronic colitis (2) were found in mice fed with diet and LCA.CONCLUSION: Precancerous or cancerous pathological lesions could not be identified. Instead, adenomatous colonic injuries occurred in a shorter period of time (six months), compared to the reported data.

Biological characteristics and probiotic effect of Leuconostoc lactis strain isolated from the intestine of black porgy fish

A strain of lactic acid bacteria, Leuconostoc lactis, was isolated from the intestinal tract of black porgy, Sparus macrocephalus, and identified by conventional biochemical characteristics and 16S rDNA gene sequence analysis. The isolated strain had the ability of bile tolerance and resistance to low pH, and survived well in the trypsinase and pepsin solution. But the highly concentrated dose of trypsinase and pepsin affect the viability of the isolated strain. The isolate was resistant to several antibiotics, including Cephalothin, Ceftriaxone, Imipenem and Tobramycin. The isolate could autoaggregate itself and coaggregate with other bacteria in vitro. The autoaggregation percentage increased to 23.29% after 20 h of incubation. The percentage of coaggregation were respectively 31.21%, 29.44%, 10.74%, 16.49%, 24.36%, 24.41% and 20.99% for Vibrio parahaemolyticus, Listeria monocytogenes, Escherichia coli O157, Salmonella typhimurium, Shigella, Staphylococcus aureus and Proteusbacillus vulgaris after 20 h incubation of a mixed suspension. The supernatant of the strain inhibited the growth of several pathogens, such as V.parahaemolyticus, Vibrio harveyi, Vibrio alginolyticus, Staphylococcus aureus, Escherichia coli O157, Salmonella typhimurium, Bacillus subtilis, Proteusbacillus vulgaris and Shigella. These results indicated that the isolate, Leuconostoc lactis, might be an attractive candidate for perspectival strain for probiotics in marine aquaculture.