Apoptotic cell death in the lactating mammary gland is enhanced by a folding variant of alpha-lactalbumin.

Abstract

Apoptosis is essential to eliminate secretory epithelial cells during the involution of the mammary gland. The environmental regulation of this process is however, poorly understood. This study tested the effect of HAMLET (human alpha-lactalbumin made lethal to tumor cells) on mammary cells. Plastic pellets containing HAMLET were implanted into the fourth inguinal mammary gland of lactating mice for 3 days. Exposure of mammary tissue to HAMLET resulted in morphological changes typical for apoptosis and in a stimulation of caspase-3 activity in alveolar epithelial cells near the HAMLET pellets but not more distant to the pellet or in contralateral glands. The effect was specific for HAMLET and no effects were observed when mammary glands were exposed to native a-lactalbumin or fatty acid alone. HAMLET also induced cell death in vitro in a mouse mammary epithelial cell line. The results suggest that HAMLET can mediate apoptotic cell death in mammary gland tissue.

• Authors: A Baltzer, C Svanborg, R Jaggi
• Journal: Cellular and molecular life sciences : CMLS (Cell Mol Life Sci) Vol. 61 Issue 10 Pg. 1221-8 (May 2004) ISSN: 1420-682X [Print] Switzerland
• PMID: 15141307 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Lactalbumin
• CASP3 protein, human
• Casp3 protein, mouse
• Caspase 3
• Caspases

Topics

• Animals
• Apoptosis
• Breast Neoplasms (metabolism)
• Caspase 3
• Caspases (metabolism)
• Cell Line
• Cell Nucleus (metabolism)
• DNA Fragmentation
• Humans
• Immunohistochemistry
• In Situ Nick-End Labeling
• Lactalbumin (chemistry, metabolism)
• Lactation
• Mammary Glands, Animal (metabolism, pathology)
• Mice
• Protein Folding
• Weaning