Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Because protein degradation in liver and skeletal muscle is increased by thyroid hormones and decreased by thyroidectomy; we investigated the influence of thyroid hormones on the level of lysosomal enzymes. Hypophysectomized rats received daily injections of L-thyroxine or L-triiodothyronine. After 3 days of this regimen, homogenates of liver and skeletal muscle showed a 2- to 3-fold increase in the activities of cathepsin D, cathepsin B, and other lysosomal enzymes including leucine aminopeptidase, acid phosphatase, beta-galactosidase, N-acetylglucosaminidase, and alpha-mannosidase. In liver, this effect reflected increased enzyme activity in the two subcellular fractions that normally contain lysosomes. Titration of cathepsin D with pepstatin indicated that the increase in this activity resulted from an increase in the number of enzyme molecules. These effects occurred with both pharmacologic (thyrotoxic) and physiologic (growth-promoting) doses of thyroid hormones. Liver and skeletal muscle from thyroidectomized rats had approximately 50% of the normal levels of lysosomal enzyme activities. Under these various conditions, heart and kidney, tissues in which protein degradation does not appear to be influenced by thyroid hormones, showed no significant changes in lysosomal hydrolases. Thus, thyroid hormones regulate proteolytic and other lysosomal enzyme activities in those tissues in which these hormones influence protein degradation. Many characteristic features of hyperthyroidism and hypothyroidism may result from changes in levels of lysosomal enzymes.
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PMID:Thyroid hormones control lysosomal enzyme activities in liver and skeletal muscle. 27 25

Four aspects of advances in inborn errors of metabolism (IEM) are analysed: 1) concerning the general comprehension of the pathogenesis, genic localization and genetic heterogeneity; 2) clinical aspects, with description of new variants of known IEM or new IEM; 3) laboratory diagnostic tests presently used in our country: dosage of some genetic markers (arylsulfatases, hexosaminidases, beta-glycosidase; beta-galactosidase and sphingomyelinase), newborn populational screening (for hyperphenylalaninemia, and hypothyroidism), heterozygote detection (for Tay-Sachs disease) and also some prenatal diagnosis; 4) therapeutic aspects presenting substitutive treatment, special diets, plasmapheresis and leukapheresis. The first results of 4 cases of mucopolysaccharidosis treated with the last technic are presented.
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PMID:[Recent advances in inborn errors of metabolism]. 332 40

This study examines the effect of changes of thyroid and glucocorticoid status on the development of ileal neuraminidase and acid beta-galactosidase. Thyroxine (T4) administration on postnatal days 6-13 had no effect on the activity of either enzyme. In contrast, a single injection of cortisone acetate on day 6 caused a precocious reduction of the activities of both enzymes. Hypothyroidism delayed the usual developmental decline of neuraminidase activity and prevented the decline of acid beta-galactosidase activity. This was probably due to an effect of T4 on endogenous glucocorticoids because cortisone acetate was just as effective as T4 in restoring enzyme activities to control levels. Adrenalectomy delayed the decline of both enzyme activities whereas glucocorticoid replacement in these same animals depressed enzyme activities to, or below, control levels. It is likely that glucocorticoids act as the primary cue in the maturation of these enzymes, but with T4 interaction necessary for the normal pattern to be elicited.
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PMID:Hormonal control of postnatal development of ileal neuraminidase and acid beta-galactosidase. 641 Nov 36

The impact of hyper- and hypothyroidism on prostatic glycosidases was investigated. Hyper-thyroidism was induced by administering L-thyroxine (25 micrograms/100 g body weight/day) for 60 days and hypothyroidism was induced by total thyroidectomy. To test the direct influence of thyroid hormones, prostatic lobes were incubated with different concentrations (10, 25 and 50 ng/mL) of T3 and beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase were assayed. Serum levels of thyroid hormones, oestradiol and testosterone increased in hyperthyroid, and decreased in hypothyroid rats. TSH decreased in hyperthyroid, and an opposite trend was seen in thyroidectomized, rats. Prostatic [anterior (coagulating glands), dorsolateral and ventral prostates] beta-glucosidase, beta-galactosidase, beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase activities increased uniformly in hyperthyroid, and decreased in thyroidectomized, rats. In vitro studies showed a dose-dependent stimulatory effect of T3 on beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase in all three lobes of the prostate. From the present study, it is concluded that hyperthyroidism augments and hypothyroidism inhibits prostatic glycosidases and T3 has a direct stimulatory effect on these enzymes.
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PMID:Impact of altered thyroid hormone status on prostatic glycosidases. 966 96