Thyrocytes are known for their ability to iodinate thyroglobulin from which the thyroid hormones are generated. In the intact thyroid gland the iodination process is almost exclusively executed at the apical plasma membrane of thyroid epithelial cells. Here, we show that freshly isolated thyrocytes iodinated polypeptides other than thyroglobulin and that one of the major iodinated polypeptides ...

The ventricular myocardium was studied in A/J mice and in Sprague-Dawley rats. In male mice, the ventricles were slightly larger and the specific activities of the lysosomal hydrolases, /8-glucuronidase, hexosaminidase, /?-galactosidase, and arylsulphatase, and the inner mitochondrial enzyme cytochrome c oxidase were substantially higher than in female mice. Orchiectomy abolished this sex diffe...

The ventricular myocardium was studied in A/J mice and in Sprague-Dawley rats. In male mice, the ventricles were slightly larger and the specific activities of the lysosomal hydrolases, beta-glucuronidase, hexosaminidase, beta-galactosidase, and arylsulphatase, and the inner mitochondrial enzyme cytochrome c oxidase were substantially higher than in female mice. Orchiectomy abolished this sex d...

OBJECTIVE Globotriaosylceramide (Gb3) induces KCa3.1 downregulation in Fabry disease (FD). We investigated whether Gb3 induces KCa3.1 endocytosis and degradation. APPROACH AND RESULTS KCa3.1, especially plasma membrane-localized KCa3.1, was downregulated in both Gb3-treated mouse aortic endothelial cells (MAECs) and human umbilical vein endothelial cells. Gb3-induced KCa3.1 downregulation was...

The ventricular myocardium was studied in A/J mice and in Sprague-Dawley rats. In male mice, the ventricles were slightly larger and the specific activities of the lysosomal hydrolases, /8-glucuronidase, hexosaminidase, /?-galactosidase, and arylsulphatase, and the inner mitochondrial enzyme cytochrome c oxidase were substantially higher than in female mice. Orchiectomy abolished this sex diffe...

Membranes were prepared from lysosomes purified 80-fold by centrifugation in a discontinuous metrizamide gradient. When salt-washed membranes were combined with rabbit muscle actin, an increase in viscosity could be measured using a falling ball viscometer. The lysosomal membrane-actin interaction was actin- and membrane-concentration dependent and appeared to be optimal under presumed physiolo...

Cadmium (Cd), a highly ubiquitous heavy metal, is a well-known inducer of neurotoxicity. However, the mechanism underlying cadmium-induced neurotoxicity remains unclear. In this study, we found that Cd inhibits autophagosome-lysosome fusion and impairs lysosomal function by reducing the levels of lysosomal-associated membrane proteins, inhibiting lysosomal proteolysis and altering lysosomal pH,...

Alzheimer's disease (AD) is caused by the cerebral deposition of beta-amyloid (Abeta), a 38-43-amino acid peptide derived by proteolytic cleavage of the amyloid precursor protein (APP). Initial studies indicated that final cleavage of APP by the gamma-secretase (a complex containing presenilin and nicastrin) to produce Abeta occurred in the endosomal/lysosomal system. However, other studies sho...

Lysosomal phospholipases play a critical role for degradation of cellular membranes after their lysosomal segregation. We investigated the regulation of lysosomal phospholipase A1 by cholesterol, phosphatidylethanolamine, and negatively-charged lipids in correlation with changes of biophysical properties of the membranes induced by these lipids. Lysosomal phospholipase A1 activity was determine...