Help
Subscribe


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

 20 April 2018

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

 20 April 2018 
Obesity and physical activity in diverticulosis
 20 April 2018 
Worldwide H.pylori prevalence
 20 April 2018 
Adalimumab with azathioprine in Crohn's
 20 April 2018 
Antibody suitable for further clinical development to complement existing therapeutic strategies for HCV
 19 April 2018 
Fibrosis in patients with chronic hepatitis B
 19 April 2018 
c-Myc expression and pancreatic cancer
 19 April 2018 
Olmesartan prescription in the USA
 18 April 2018 
Online tool predicts bowel dysfunction severity prior to anterior resection
 18 April 2018 
Hep C treatment for sustained virologic response
 18 April 2018 
Endoscopic necrosectomy reduces risk of death 
 17 April 2018 
Colorectal cancer screening and ethnic inequities
 17 April 2018 
Training programs should consider radiation education for advanced endoscopy fellows
 17 April 2018 
Aspirin and pancreatic cancer
 16 April 2018 
Surgery for colorectal polyps has increased 
 16 April 2018 
Advanced fibrosis can be ruled out in primary health care patients
 16 April 2018 
Antibiotic use and colorectal adenoma
 13 April 2018 
Colorectal cancer cell lines
 13 April 2018 
Infliximab and corticosteroid-free clinical remission in Crohn's
 13 April 2018 
Teduglutide for children with short bowel syndrome
 12 April 2018 
Prescriptions for opiate drugs amongst primary care patients with IBD
 12 April 2018 
Lower GI bleeding related to comorbidity
 12 April 2018 
non–Clostridium difficile bacterial infections in IBD
 11 April 2018 
Physician perception of IBD trial results
 11 April 2018 
Bile acid deficiency in IBS 
 11 April 2018 
Stem cell therapy for fistulas in Crohn's
 10 April 2018 
Overweight in childhood and type 2 diabetes
 10 April 2018 
immunoglobulin G associates with clinical features of IBD
 10 April 2018 
T-cells repertoires in celiac disease
 09 April 2018 
Biomarker tests for colorectal cancer screening
 09 April 2018 
Fecal transplantation in C. difficile infection and treatment outcome 
 09 April 2018 
No weigh-loss drug improved all cardiometabolic risk factors
 06 April 2018 
Colonoscopy and colorectal cancer mortality
 06 April 2018 
Eosinophilic esophagitis and health-related quality of life
 06 April 2018 
Microbiome in athletes vs sedentary subjects
 05 April 2018 
Laparoscopic Nissen fundoplication for GERD treatment
 05 April 2018 
Random biopsies for neoplasia in IBD
 05 April 2018 
Scoring system identifies cancer risk in Barrett's
 04 April 2018 
Alpha‐1 antitrypsin deficiency and liver disease
 04 April 2018 
PPI and risk of stroke
 04 April 2018 
Adjuvant chemotherapy for advanced colon cancer
 29 March 2018 
Prevention of metachronous gastric cancer
 29 March 2018 
Acute lower GI bleeding
 28 March 2018 
Decision aid used by IBD patients
 28 March 2018 
Transition for young adults with IBD
 28 March 2018 
Amitriptyline in functional dyspepsia
 27 March 2018 
Emergency department utilization for IBD 
 27 March 2018 
Management of hemorrhoids in the USA
 27 March 2018 
Adult ulcerative colitis
 26 March 2018 
Biological therapy response in IBD 
 26 March 2018 
Obesity and diverticulosis
 26 March 2018 
Practice guidelines for chronic constipation
 23 March 2018 
Health-related quality of life in eosinophilic esophagitis
 23 March 2018 
Genetics and chronic liver disease
 23 March 2018 
Global prevalence of H.pylori
 22 March 2018 
H. pyloris and gastric cancer
 22 March 2018 
Pancreatitis after IBS treatment 
 22 March 2018 
Mechanisms of action in patients with IBS
 21 March 2018 
Panel markers for early detection of colon cancer

 21 March 2018 
Blood test differentiates celiac disease
 21 March 2018 
Patient characteristics and colonoscopy preparation

Blackwell Publishing


GastroHep.com is a Blackwell Publishing registered trademark
© 2018 Wiley-Blackwell and GastroHep.com and contributors
Privacy Statement
Disclaimer
About Us