An abnormally high level of the sucrase-isomaltase (SI) complex in the small intestine of rats with streptozotocin-induced insulin-dependent diabetes mellitus (IDDM) was normalized in 11 h by the administration of insulin, in addition to normalization of the blood glucose level. Phlorizin, an inhibitor of renal glucose reabsorption, also caused normalization of the blood glucose level in the IDDM rats; however, the level of the SI complex was barely changed. When mucosa explants were cultured in a medium, the SI complex synthesized during the cultivation was accumulated as its precursor protein without maturation, owing to the absence of pancreatic proteases, and the amount of the precursor protein that accumulated in the explants was decreased by the addition of insulin into the medium. Further, the mRNA level of the SI complex in the explants incubated with insulin was obviously lower than that in the absence of insulin. These results indicate that insulin has a suppressive effect on the synthesis of the SI complex, presumably by decreasing the transcriptional level of the gene encoding the complex, in small-intestinal epithelial cells. Thus the synthesis of the SI complex might exceed normal levels in the epithelial cells as a direct result of the depletion of insulin under IDDM conditions.
Skip Nav Destination
Close
Article navigation
February 1998
- Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
Research Article|
February 01 1998
Suppressive effect of insulin on the synthesis of sucrase–isomaltase complex in small intestinal epithelial cells, and abnormal increase in the complex under diabetic conditions
Makoto TAKENOSHITA
;
Makoto TAKENOSHITA
1
1Department of Applied Biological Chemistry, Osaka Prefecture University, Sakai, Osaka 599, Japan
1To whom correspondence should be addressed.
Search for other works by this author on:
Ryoichi YAMAJI
;
Ryoichi YAMAJI
1Department of Applied Biological Chemistry, Osaka Prefecture University, Sakai, Osaka 599, Japan
Search for other works by this author on:
Hiroshi INUI
;
Hiroshi INUI
1Department of Applied Biological Chemistry, Osaka Prefecture University, Sakai, Osaka 599, Japan
Search for other works by this author on:
Kazutaka MIYATAKE
;
Kazutaka MIYATAKE
1Department of Applied Biological Chemistry, Osaka Prefecture University, Sakai, Osaka 599, Japan
Search for other works by this author on:
Yoshihisa NAKANO
Yoshihisa NAKANO
1Department of Applied Biological Chemistry, Osaka Prefecture University, Sakai, Osaka 599, Japan
Search for other works by this author on:
Biochem J (1998) 329 (3): 597–600.
Article history
Received:
August 29 1997
Accepted:
September 29 1997
Citation
Makoto TAKENOSHITA, Ryoichi YAMAJI, Hiroshi INUI, Kazutaka MIYATAKE, Yoshihisa NAKANO; Suppressive effect of insulin on the synthesis of sucrase–isomaltase complex in small intestinal epithelial cells, and abnormal increase in the complex under diabetic conditions. Biochem J 1 February 1998; 329 (3): 597–600. doi: https://doi.org/10.1042/bj3290597
Download citation file:
Close
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Biochemical Society Member Sign in
Sign InSign in via your Institution
Sign in via your InstitutionGet Access To This Article
Cited By
Related Articles
Does Residual Insulin Secretion (Assessed by C-Peptide Concentration) Affect Lipid and Lipoprotein Levels in Insulin-Dependent Diabetes Mellitus?
Clin Sci (Lond) (October,1989)
Cytokine regulation of glutamate decarboxylase biosynthesis in isolated rat islets of Langerhans
Biochem J (August,1996)