Aging and Digestive Diseases: At the View of the Functional Change of Gastrointestinal Tract / 대한소화기학회지

Although it is difficult to define the term "aging" consensually, in medical fields, usually it means the progressive accumulation of irreversible degenerative changes leading to loss of homeostasis. It is supposable that there is also modest decline in the structure and function of several digestive organs. However, data about this subject are not enough. Main problem in studying aging digestive organ is that discrimination of primary senile change of the organ with secondary one from other senile diseases is not easy. That is, the prevalence of many non-digestive disorders which can badly affect the digestive functions is increasing by aging; for example, diabetes, malignancy, etc. To prove that some phenomenon is as result of pure senile change, it is necessary to exclude secondary one, but, the process is very complicated and difficult. In spite of this limitation, here, I will discuss the senile change of several digestive organs by aging, especially at the view of the gastrointestinal functions, with review of literatures.

Epithelial effects of proteinase-activated receptors in the gastrointestinal tract

The intestinal epithelium plays a crucial role in providing a barrier between the external environment and the internal milieu of the body. A compromised mucosal barrier is characteristic of mucosal inflammation and is a key determinant of the development of intestinal diseases such as Crohn's disease and ulcerative colitis. The intestinal epithelium is regularly exposed to serine proteinases and this exposure is enhanced in numerous disease states. Thus, it is important to understand how proteinase-activated receptors (PARs), which are activated by serine proteinases, can affect intestinal epithelial function. This review surveys the data which demonstrate the wide distribution of PARs, particularly PAR-1 and PAR-2, in the gastrointestinal tract and accessory organs, focusing on the epithelium and those cells which communicate with the epithelium to affect its function. PARs have a role in regulating secretion by epithelia of the salivary glands, stomach, pancreas and intestine. In addition, PARs located on subepithelial nerves, fibroblasts and mast cells have important implications for epithelial function. Recent data outline the importance of the cellular site of PAR expression, as PARs expressed on epithelia may have effects that are countered by PARs expressed on other cell types. Finally, PARs and their ability to promote epithelial cell proliferation are discussed in terms of colon cancer.

Clearance fecal de alfa-1-antitripsina en enteropatias perdedoras de proteínas en pediatría / Fecal alpha 1-antitrypsin clearance in protein-losing enteropathies in pediatrics

El clearance fecal de alfa-1-antitripsina fue realizado en 47 pacientes de edad pediátrica que presentaron diversas enfermedades digestivas: 6 con colitis ulcerosa, 5 con enfermedad celíaca, 6 con intolerancia a la proteína de la leche de vaca, 1 con linfagiectasia intestinal, 1 con giardiasis, 1 con colitis inespecífica, 1 con resección del íleon terminal, y 1 con talasemia mayor y dolor abdominal. Quince pacientes presentaron diarrea crónica inespecífica. Diez niños sin enfermedad digestiva fueron incorporados como grupo control. El 1er. grupo de niños presentó valores significativamente mayores (p < 0.05) del clearance fecal de alfa-1-antitripsina con respecto a los pacientes con diarrea crónica inespecífica y del grupo control. Solo un niño con intolerancia a la proteína de la leche de vaca tuvo un valor inferior a la media + 2 Desvío estandar. Todos los niños con diarrea crónica inespecífica presentaron valores similares a los del grupo control, con excepción de 1 que tuvo un resultado ligeramente aumentado, no hallándose diferencia significativa. El paciente con talasemia mayor y dolor abdominal presentó un valor muy elevado, desconociéndose el motivo de este hallazgo. El clearance fecal de alfa-1-antripsina es un método útil, simple, menos costoso y no invansivo que las técnicas tradicionales para el diagnóstico de enteropatía perdedora de proteínas en la infancia