How we have learned about the complexity of physiology, pathobiology and pharmacology of bile acids and biliary secretion

Abstract

During the last decades the concept of bile secretion as merely a way to add detergent components to the intestinal mixture to facilitate fat digestion/absorption and to eliminate side products of heme metabolism has evolved considerably. In the series of mini-reviews that the World Journal of Gastroenterology is to publish in its section of "Highlight Topics", we will intend to give a brief but updated overview of our knowledge in this field. This introductory letter is intended to thank all scientists who have contributed to the development of this area of knowledge in gastroenterology.© 2008 The WJG Press. All rights reserved.Key words: Bile flow; Cholestasis; Hepatocyte; Liver; Transport Marin JJG. How we have learned about the complexity of physiology, pathobiology and pharmacology of bile acids and biliary secretion.

Steroid degradation genes in Comamonas testosteroni TA441: Isolation of genes encoding a Δ4(5)-isomerase and 3α- and 3β-dehydrogenases and evidence for a 100kb steroid degradation gene hot spot

“…For the production of useful steroidal compounds, more familiar steroid compounds with modification, which includes cholic acid, cholesterol, and plant sterols, are preferable as starting materials for developing new chemicals with useful effects. These compounds are also attractive from a research perspective because a number of useful effects of these steroid compounds are known and are still under intensive investigation in searching for novel useful effects [24][25][26].…”

“…As modified steroid compounds such as the cholic acid analogs are attracting attention due to newly discovered functions (e.g. reduction of internal cholesterol level in animals and induction of defensive reactions in plants [24][25][26]), in this study we examined degradability of steroid compounds containing different side chains and double bonds ( Fig. 1) by C. testosteroni TA441 in order to identify the genes involved in the degradation of modified steroid compounds.…”

“…The major intermediate compounds in bacterial steroid degradation were identified in these studies and a degradation pathway was proposed based on these compounds. As new functions have been discovered for several steroid compounds [24][25][26], bacterial steroid degradation is re-emerging as an area of research interest. However, before our study on steroid degradation in C. testosteroni TA441, the bacterial steroid degradation pathway remained incomplete and the identification of degradation genes for only a few early-steps had been reported.…”

Supplementation of Bile Acids and Lipase in Broiler Diets for Better Nutrient Utilization and Performance: Potential Effects and Future Implications – A Review

“…Bile acids (C24) are organic components of bile usually synthesized from cholesterol in hepatocytes. Different amphipathic acidic steroids are involved in the formation of bile acid pool (Marin, 2008;Hofmann and Hagey, 2014). Bile acids are conjugated with glycine and taurine, and in some animals, with sulfate (SO4).…”

Etiopathogenesis and pathophysiology of cholestasis

“…During the last few decades, our understanding of the physiology and pathophysiology of the biliary system has dramatically increased, since the time, by the middle of the twentieth century, when the accepted concept of bile formation by hydrostatic forces was replaced by the more accurate one of osmotic filtration-driven bile flow [2,3] until the modern availability of tools capable of exploring molecular and genetic aspects of cholestasis. Many excellent scientists have contributed to the progress in this field of hepatology [4]. With this special issue on cholestasis, we want to pay homage to those who have made this extraordinary scientific jump possible and are no longer among us.…”