Gastrointestinal pathology in a mouse model of mucopolysaccharidosis type IIIA.

Abstract

Mucopolysaccharidosis type IIIA (MPS IIIA) is a lysosomal storage disorder caused by a deficiency in sulphamidase (NS), a lysosomal enzyme required for the degradation of heparan sulphate glycosaminoglycans (gags). The MPS IIIA mouse is a naturally occurring model that accurately reflects the human pathology and disease course. It displays primarily central nervous system pathology accompanied by widespread accumulation of gag in somatic tissues. MPS IIIA mice exhibit greater bodyweight gain than normal littermates and attain a higher mature bodyweight. In this study, gastrointestinal morphology and function was characterised in the IIIA mouse. Stomach and duodenum weight increased in MPS IIIA mice and duodenum length also increased. An increased submucosal thickness was observed in MPS IIIA intestine compared to normal mice and lysosomal storage of gag was observed in this region. Storage was also observed in the lamina propria of the villus tip. All other morphometric measurements including villus height and crypt depth fell within the normal range. The gastric emptying half-life of solid and liquid meals decreased with age in normal mice whereas the T(1/2) of solid meals did not alter with age in MPS IIA mice such that they were elevated above normal by 38 weeks of age. Sucrase activity was higher than normal in MPS IIIA at all ages tested. These abnormalities in GI structure and function observed in MPS IIIA may contribute to weight gain in this disorder.

• Authors: Ainslie L K Derrick Roberts, Gordon S Howarth, Wan Chin Liaw, Simon Moretta, Stamatiki Kritas, Kerry A Lymn, Roger Yazbeck, Cuong Tran, Janice M Fletcher, Ross N Butler, Sharon Byers
• Journal: Journal of cellular physiology (J Cell Physiol) Vol. 219 Issue 2 Pg. 259-64 (May 2009) ISSN: 1097-4652 [Electronic] United States
• PMID: 19170061 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Hydrolases
• N-sulfoglucosamine sulfohydrolase
• Sucrase

Topics

• Animals
• Breath Tests
• Disease Models, Animal
• Gastric Emptying (physiology)
• Gastrointestinal Tract (anatomy & histology, pathology, physiology)
• Humans
• Hydrolases (deficiency)
• Mice
• Mucopolysaccharidosis III (pathology)
• Organ Size
• Sucrase (metabolism)