Mp. Pakarinen et al., ABSORPTION, EXCRETION, AND DISTRIBUTION OF PLANT STEROLS AFTER PROXIMAL GUT RESECTION AND AUTOTRANSPLANTATION OF PORCINE ILEUM, Lipids, 33(3), 1998, pp. 267-276
Contribution of different gut segments to plant sterol absorption, ada
ptation of plant sterol absorption after partial small bowel resection
, and effects of gut transplantation (necessitates extrinsic autonomic
denervation and lymphatic disruption) on plant sterol biodynamics are
unclear. We studied the consequences of massive proximal small bowel
resection and autotransplantation of the remaining ileum on the adapti
ve absorption and biodynamics of plant sterols. Dietary, fecal, biliar
y, hepatic and plasma plant sterols, fecal elimination and absorption
of cholesterol, small bowel morphology, and intestinal transit were de
termined before (n = 5) and at 4, 8, and 14 wk after resection of the
proximal 75% of the jejunoileum (n = 15) and autotransplantation of th
e remaining ileum (n = 15) or transection (n = 5). Proximal gut resect
ion significantly reduced cholesterol absorption efficiency; percentag
e absorption and biliary secretion of plant sterols; plasma, biliary a
nd hepatic campesterol-to-cholesterol proportions; and sitosterol prop
ortions in plasma and bile. Autotransplantation of the remaining ileum
further significantly decreased cholesterol absorption efficiency; pe
rcentage absorption and biliary secretion of campesterol; campesterol
proportions in plasma, bile and liver; and plasma proportions of sitos
terol while increasing fecal excretion of neutral and acidic steroids.
Plasma proportions of the two plant sterols, but absorption of just c
ampesterol, were gradually improved with increasing cholesterol absorp
tion and villus height after proximal gut resection; the same result w
as observed to a lesser degree after ileal autotransplantation. In add
ition, significant positive correlations were found between percentage
cholesterol and campesterol absorption and the plasma plant sterol pr
oportions in both proximal resection groups, between campesterol absor
ption and ileal villus height in the resection group, and between camp
esterol absorption and intestinal transit time in the autotransplantat
ion group. In conclusion, plasma campesterol and sitosterol closely re
flect absorption of cholesterol and plant sterols from intact and auto
transplanted ileum during adaptation to proximal gut resection. A loss
of proximal gut absorptive surface impairs cholesterol and campestero
l absorption more than sitosterol absorption, the rat ter being appare
ntly less dependent on available jejunal villus surface area.