The Role of Lingual Lipase in Neonatal Fat Digestion

Gastric lipase (HGL) contributes significantly to fat digestion. However, little is known about its neurohormonal regulation in humans. We studied the role of CCK and cholinergic mechanisms in the postprandial regulation of HGL and pancreatic lipase (HPL) secretion in six healthy subjects. Gastric emptying of a mixed meal and outputs of HGL, pepsin, acid, and HPL were determined with a double-indicator technique. Three experiments were performed in random order: intravenous infusion of 1) placebo, 2) low-dose atropine (5 micrograms.kg-.h-1), and 3) the CCK-A receptor antagonist loxiglumide (22 mumol.kg-.h-1). Atropine decreased postprandial outputs of HGL, pepsin, gastric acid, and HPL (P < 0.03) while slowing gastric emptying (P < 0.05). Loxiglumide markedly increased the secretion of HGL, pepsin, and acid while distinctly reducing HPL outputs and accelerating gastric emptying (P < 0.03). Plasma CCK and gastrin levels increased during loxiglumide infusion (P < 0.03). Atropine enhanced gastrin but not CCK release. Postprandial HGL, pepsin, and acid secretion are under positive cholinergic but negative CCK control, whereas HPL is stimulated by cholinergic and CCK mechanisms. We conclude that CCK and cholinergic mechanisms have an important role in the coordination of HGL and HPL secretion to optimize digestion of dietary lipids in humans.

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Mechanisms of intestinal fat absorption

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1981.240.1.g1 ◽

1981 ◽

Vol 240 (1) ◽

pp. G1-G9 ◽

Cited By ~ 7

Author(s):

Y. F. Shiau

Keyword(s):

Water Layer ◽

Fat Absorption ◽

Fatty Acid Binding ◽

Unstirred Water Layer ◽

Fat Digestion ◽

New Concepts ◽

Intestinal Fat Absorption ◽

Micellar Formation ◽

Bile Salt Micelle

Even though most of the major controversies regarding intestinal fat absorption have been resolved over the past three decades, our concepts of fat digestion and absorption continue to be modified, and new concepts have emerged. The purpose of this review is to summarize advances in our understanding of fat digestion and absorption since the topic was last reviewed by Johnston in 1968. The discussion will emphasize 1) the role of colipase and its interactions with lipase, bile salt micelle, and triglyceride substrate; 2) the importance of the unstirred water layer in fat absorption; 3) micellar formation and dissociation; 4) the role of fatty acid binding protein; 5) factors influencing the reesterification mechanisms in the intestine; and 6) intestinal contribution to lipoprotein and apoprotein production. The importance of these new concepts and the remaining gaps in our understanding of these complex digestive and absorptive processes are discussed.

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A Review. Fat Digestion in the Newborn: Role of Lingual Lipase and Preduodenal Digestion

Pediatric Research ◽

10.1203/00006450-197905000-00008 ◽

1979 ◽

Vol 13 (5) ◽

pp. 615-622 ◽

Cited By ~ 87

Author(s):

Margit Hamosh

Keyword(s):

Fat Digestion

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Role of fat digestion and fatty acid chain length in the induction of gastrointestinal sensations in humans

Gastroenterology ◽

10.1016/s0016-5085(01)83538-1 ◽

2001 ◽

Vol 120 (5) ◽

pp. A710-A711

Author(s):

C FEINLE ◽

T RADES ◽

B OTTO ◽

M FRIED

Keyword(s):

Fatty Acid ◽

Chain Length ◽

Fatty Acid Chain Length ◽

Fatty Acid Chain ◽

Fat Digestion

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Role of Lingual and Gastric Lipases in Fat Digestion and Absorption

Lingual and Gastric Lipases: Their Role in Fat Digestion ◽

10.1201/9780429282867-7 ◽

2020 ◽

pp. 179-227

Author(s):

Margit Hamosh

Keyword(s):

Fat Digestion

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Digestion and mucosal absorption of fat in normal and bile-deficient dogs

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1963.204.3.509 ◽

1963 ◽

Vol 204 (3) ◽

pp. 509-514 ◽

Cited By ~ 16

Author(s):

Leon K. Knoebel ◽

John M. Ryan

Keyword(s):

Fatty Acids ◽

Free Fatty Acids ◽

Mucosal Cell ◽

Fat Absorption ◽

High Concentration ◽

Fat Digestion ◽

Mucosal Absorption ◽

Cell Changes ◽

Dietary Origin

The role of bile in fat digestion and absorption was investigated by studying the intestinal intraluminar and mucosal cell changes which occur after feeding either cottonseed oil triglycerides or oleic acid to normal dogs and to dogs deprived of bile by cholecystonephrostomy. Although the intraluminar lipids of the bile-deficient dogs contained a higher than normal concentration of monoglycerides, lipolysis, as based on the high concentration of intraluminar free fatty acids, was quite extensive in the absence of bile and comparable to that obtained in normal dogs. The conclusion is that bile does not play an important intraluminar role in fat absorption associated with lipolysis. Mucosal lipid of dietary origin recovered after feeding either triglycerides or free fatty acids to normal dogs was primarily in the form of higher glycerides, whereas that recovered from the mucosa of bile-deficient dogs contained a larger than normal proportion of free fatty acids. This result suggests that the intracellular esterification of the absorbed products of fat digestion is retarded in the absence of bile.

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