Factors Influencing Choline Absorption in the Intestinal Tract 1

Abstract

Previous investigations ( 1 ) have demonstrated that in normal persons approximately 60 per cent of choline salts fed in a single dose is transformed by intestinal bacteria to trimethylamine (TMA), which is excreted in the urine mainly as the oxide. In chronic liver diseases, considerably less of the ingested choline appears in the urine as total trimethylamines (TTMA). This difference was considered as evidence of an altered action of the intestinal bacteria in these diseases ( 1 ). The concept of the intestinal formation of urinary trimethylamines, based in part upon the reduction of TTMA excretion following administration of antimicrobial agents, was confirmed by the observation (2) that choline as such appears in the urine after intravenous administration of choline, but the basal excretion of urinary TTMA is not altered significantly. The concept of altered choline utilization by intestinal bacteria in liver diseases, as reflected by reduced transformation of choline to TMA, required further elaboration. This was partly carried out in animal experiments (3), but in addition it was necessary to perform a series of clinical studies to clarify the results of human and animal investigations reported previously. Studies of the physiologic processes included the following: (a) whether choline bound in the form of phospholipids is transformed to TMA to the same degree as are choline salts, (b) investigation into the site and completeness of intestinal transformation of choline, and (c) determination of the effects of aureomycin upon the transformation of large amounts of choline.

Blood Coagulation and Fibrinolysis in Relation to Coronary Heart Disease

“…Serum albumin and globulin were determined by Weichselbaum's (1946) method as modified by Wolfson et al (1948). Thymol turbidity was estimated by Maclagan's (1944) method as modified by De la Huerga and Popper (1949), zinc sulphate turbidity according to Kunkel (1947), serum urea by the method of Archer and Robb (Harrison, 1947), and serum urate by the spectrophotometric method of Praetorius and Poulsen (1953).…”

The Effects of Antimicrobial Agents Upon Choline Degradation in the Intestinal Tract

“…Choline was given orally in the form of bicarbonate 1 in amounts containing 4 Gm. choline base (460 mg. N) with the exception of the four normal subjects who received 5.4 Gm.…”

“…Part of the evidence gathered to establish this phenomenon was that, following ingestion of choline with aureomycin, much less TTMA than usual were excreted (3,4). Further experiments were undertaken to elaborate upon the inhibition of TTMA formation from choline by antimicrobial agents.…”

Studies on the Absorption of Choline Chloride * , †

“…De la Huerga and Popper (1,2) conclude that most of the ingested choline in man is converted to trimethylamine (TMA) or its oxide (TMAO), through the action of bacteria in the small intestine and that these products are then absorbed. Wiinsche (3) (6) show that liver homogenate and liver slices are able to convert choline to TMA.…”

“…Harris (1) found that all available pyridoxineless mutants of Neurospora sitophila grow better a t limiting pyridoxine concentrations if thiamine…”