Help
Subscribe


GastroHep.com - the global online resource for all aspects of gastroenterology, hepatology and endoscopy

 19 November 2017

Advanced search
GastroHep.com - the global online resource for all aspects of gastroenterology, hepatology and endoscopy Profile of Roy Pounder

Home

News  
Journals
Review Articles
Slide Atlas
Video Clips
Online Books
Advanced Digestive Endoscopy
Classical Cases
Conference Diary
PubMed
International GH Links
USA GH Links
National GH Links
National GI Societies
Other Useful Links




Emails on Gastroenterology and Hepatology
the National AIDS Treatment Advocacy Project
Visit the gastroenterology section of the EUMS

News

Expression of intestinal iron transporters regulated in iron-dependent manner

Expression levels of two iron transporters are regulated in an iron-dependent manner, according to research published in the April issue of American Journal of Physiology - Gastrointestinal and Liver Physiology.

News image

fiogf49gjkf04

A team from Massachusetts, USA, investigated the intestinal expression of genes involved in iron absorption in humans.

Hereditary hemochromatosis (HHC) is one of the most frequent genetic disorders in humans.

In healthy individuals, cells with the highest iron demand, in particular erythroid precursors, tightly regulate absorption of iron in the intestine.

Cloning of intestinal iron transporter proteins has provided new insight into mechanisms and regulation of intestinal iron absorption.

The researchers assessed whether, in humans, the two transporters are regulated in an iron-dependent manner and whether this regulation is disturbed in HHC.

Duodenal biopsy samples were taken from individuals with normal iron levels, iron-deficiency anemia, and iron overload.

Using quantitative PCR, mRNA expression of divalent cation transporter 1 (DCT1), iron-regulated gene 1 (IREG1), and hephaestin were measured in these samples.

DCT1 and IREG1 mRNA levels are regulated in an iron-dependent manner.
American Journal of Physiology - Gastrointestinal and Liver Physiology

In controls, the investigators found inverse relationships between the DCT1 splice form (containing an iron-responsive element [IRE]) and blood hemoglobin, serum transferrin saturation, or ferritin.

Subjects with iron-deficiency anemia showed a significant increase in expression of the spliced form, DCT1(IRE) mRNA.

Similarly, in subjects homozygous for the C282Y HFE mutation, DCT1(IRE) expression levels remained high despite high serum iron saturation.

Furthermore, a significantly increased IREG1 expression was observed.

The team found that hephaestin did not exhibit a similar iron-dependent regulation.

Andreas Rolfs, of the Harvard Medical School, Boston, Massachusetts, said on behalf of the group, "Our data show that expression levels of human DCT1 mRNA, and to a lesser extent IREG1 mRNA, are regulated in an iron-dependent manner. However, hephaestin mRNA is not affected."

"The lack of appropriate downregulation of apical and basolateral iron transporters in duodenum likely leads to excessive iron absorption in persons with HHC," it was concluded.

Am J Gastrointest Liver Physiol 2002; 282 (4): G598-607
20 March 2002

Go to top of page Email this page Email this page to a colleague

 17 November 2017 
Food elimination diets for treatment of adults with eosinophilic esophagitis
 17 November 2017 
PPI use and cognitive function in women
 17 November 2017 
Predicting microscopic colitis
 16 November 2017 
NAFLD-hepatocellular carcinoma and survival after orthotopic liver transplant
 16 November 2017 
Prepregnancy obesity and severe maternal morbidity
 16 November 2017 
Celiac disease screening in adult first-degree relatives
 15 November 2017 
Breastfeeding and the risk of IBD
 15 November 2017 
Medication nonadherence and health care costs
 15 November 2017 
Predicting recurrence after curative rectal cancer surgery
 14 November 2017 
HBV/HCV coinfection and cirrhosis
 14 November 2017 
Sexual dysfunction after rectal cancer surgery
 14 November 2017 
Eosinophilic gastroenteritis and colitis
 13 November 2017 
GI bleeding in patients taking non–vitamin K antagonist oral anticoagulants
 13 November 2017 
Genetic polymorphisms, fatty acids and ulcerative colitis
 13 November 2017 
Flares after immunomodulator withdrawal in Crohn's
 10 November 2017 
Thiopurines vs TNF and lymphoma risk in IBD
 10 November 2017 
Drug monitoring of anti-tumour necrosis factor therapy in IBD
 10 November 2017 
Treatment decisions for older patients with colorectal cancer
 09 November 2017 
Quality standards in upper gastrointestinal endoscopy
 09 November 2017 
Irradiated rectal cancer and chemoradiotherapy
 09 November 2017 
Environmental factors and IBD
 08 November 2017 
Prophylaxis of spontaneous bacterial peritonitis
 08 November 2017 
Socioeconomic characteristics in diverticular disease
 08 November 2017 
Optimal management of postoperative Crohn's disease
 07 November 2017 
Community Screening for Helicobacter pylori
 07 November 2017 
Early readmission in IBD patients
 07 November 2017 
Mesocolic excision for colon cancer
 06 November 2017 
Food elimination diet for children with eosinophilic esophagitis
 06 November 2017 
Biologic agents and obesity in children with IBD
 06 November 2017 
Liver cancer burden despite extensive use of antiviral agents
 03 November 2017 
Statins and mortality in chronic viral hepatitis
 03 November 2017 
Propofol for outpatient colonoscopy
 03 November 2017 
Asthma and IBD development
 02 November 2017 
Diverticulitis and emergency department burden
 02 November 2017 
Rural residence and risk of IBD
 02 November 2017 
Sexual functioning in Hep C
 01 November 2017 
Heartburn relief in adolescents with GERD
 01 November 2017 
Barriers to hepatitis C treatment
 01 November 2017 
Autoimmune pancreatitis in children
 31 October 2017 
Surveillance in ulcerative colitis and Crohn’s disease
 31 October 2017 
Endoscopic indices of disease activity for Crohn’s
 31 October 2017 
Follow-up of positive results on fecal blood tests
 30 October 2017 
Local recurrence after curative rectal cancer surgery
 30 October 2017 
Low-flow ascites pump in refractory cirrhosis
 30 October 2017 
Medical therapy of patients with pediatric-onset IBD
 27 October 2017 
NAFLD in advanced fibrosis in the USA
 27 October 2017 
Early readmission in cirrhosis after bacterial infections
 26 October 2017 
Predicting response to anti-TNF therapy in Crohn's
 26 October 2017 
Conversion to open laparotomy in rectal cancer
 25 October 2017 
Conversion of colonoscopy to sigmoidoscopy
 25 October 2017 
Fecal microbiota transplantation
 25 October 2017 
Rifaximin and survival in hepatic encephalopathy
 24 October 2017 
Eosinophilic esophagitis with swallowed topical corticosteroids
 24 October 2017 
Meta-analysis in nutritiona research
 23 October 2017 
NAFLD-related hepatocellular carcinoma in liver resection
 23 October 2017 
Outcome of hepatic sarcoidosis
 20 October 2017 
Hospital readmissions reduction program
 20 October 2017 
Conversion of planned colonoscopy to sigmoidoscopy
 19 October 2017 
Fecal immunochemical tests in colorectal cancer screening
 19 October 2017 
Current management of chylous ascites

Blackwell Publishing


GastroHep.com is a Blackwell Publishing registered trademark
© 2017 Wiley-Blackwell and GastroHep.com and contributors
Privacy Statement
Disclaimer
About Us