Regulation of lysosomal enzymes. I. Adaptive changes in enzyme activities during starvation and refeeding

1969 ◽  
Vol 47 (8) ◽  
pp. 785-790 ◽  
Author(s):  
I. D. Desai
Keyword(s):  
Enzyme Activities ◽  
Cathepsin D ◽  
Lysosomal Enzymes ◽  
Starvation Period ◽  
Body Tissues ◽  
Body Weights ◽  
Close Relationship ◽  
Adaptive Processes ◽  
Liver And Kidney ◽  
Irreparable Damage

The changes in the activity of five representative lysosomal enzymes of rat liver and kidney, namely acid phosphatase, β-glucuronidase, β-galactosidase, arylsulfatase, and cathepsin D, during starvation and refeeding have been studied. When rats were fasted for periods of up to 120 h, both free and total activities of hepatic lysosomal enzymes progressively increased reaching levels two to seven times higher than those of fed controls. On resuming feeding at the end of a starvation period, enzyme activities rapidly returned to normal. There was a close relationship between increased lysosomal enzymes during starvation and loss in liver and body weights of the animal. These findings, taken together, suggest a specific role for lysosomal enzymes in adaptive processes requiring turnover of body tissues for maintenance and survival of the animal without doing itself irreparable damage during starvation.

Regulation of Lysosomal Enzymes. II. Reversible Adaptation of Intestinal Acid Hydrolases During Starvation and Realimentation

1971 ◽  
Vol 49 (2) ◽  
pp. 170-176 ◽  
Author(s):  
I. D. Desai
Keyword(s):  
Lysosomal Enzymes ◽  
Specific Activity ◽  
The Body ◽  
Starvation Period ◽  
Small Intestinal Mucosa ◽  
Acid Hydrolases ◽  
Lysosomal Hydrolases ◽  
Intestinal Tissue ◽  
Body Tissues ◽  
Dietary Nutrients

The nutritional role of intestinal lysosomal enzymes in the regulation of reversible adaptation to starvation and realimentation by various dietary treatments is investigated. When rats were starved for periods ranging from 72 to 120 h, the specific activity of the representative lysosomal hydrolases, viz. acid phosphatase, β-glucuronidase, β-galactosidase, arylsulfatase, and cathepsin D of small intestinal mucosa, progressively increased reaching levels two to four times higher than the fed controls. During the starvation period of only 72 h, more than 60% of the intestinal weight and about 75% of the mucosal protein was lost. On realimentation with a complete diet such as laboratory rat chow, the specific activity of the intestinal lysosomal enzymes rapidly returned to normal and the lost weight of the intestinal tissue and of the body as a whole was restored. The regulatory effect of major dietary nutrients such as carbohydrates, proteins, and fats on the starvation-induced breakdown of the intestinal tissue reserves is presented and discussed. The findings of this study indicate that changes in the specific activity of the intestinal lysosomal enzymes are associated with adaptive processes requiring rapid turnover of body tissues for maintenance and survival of the animal during starvation and/or during conditions when dietary supply of certain nutrients is limited.

scholarly journals Castration causes an increase in lysosomal size and upregulation of cathepsin D expression in principal cells along with increased secretion of procathepsin D and prosaposin oligomers in adult rat epididymis

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0250454
Author(s):  
Lorena Carvelli ◽  
Andrea Carolina Aguilera ◽  
Leila Zyla ◽  
Laura Lucía Pereyra ◽  
Carlos R. Morales ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Complex Formation ◽  
Cathepsin D ◽  
Initial Segment ◽  
Lysosomal Enzymes ◽  
Sperm Maturation ◽  
Principal Cells ◽  
Adult Rat ◽  
Rat Epididymis ◽  
Lysosomal Proteins

In the epididymis, lysosomal proteins of the epithelial cells are normally targeted from the Golgi apparatus to lysosomes for degradation, although their secretion into the epididymal lumen has been documented and associated with sperm maturation. In this study, cathepsin D (CatD) and prosaposin (PSAP) were examined in adult epididymis of control, and 2-day castrated rats without (Ct) and with testosterone replacement (Ct+T) to evaluate their expression and regulation within epididymal epithelial cells. By light microscope-immunocytochemistry, a quantitative increase in size of lysosomes in principal cells of Ct animals was noted from the distal initial segment to the proximal cauda. Androgen replacement did not restore the size of lysosomes to control levels. Western blot analysis revealed a significant increase in CatD expression in the epididymis of Ct animals, which suggested an upregulation of its expression in principal cells; androgens restored levels of CatD to that of controls. In contrast, PSAP expression in Ct animals was not altered from controls. Additionally, an increase in procathepsin D levels was noted from samples of the epididymal fluid of Ct compared to control animals, accompanied by an increased complex formation with PSAP. Moreover, an increased oligomerization of prosaposin was observed in the epididymal lumen of Ct rats, with changes reverted to controls in Ct+T animals. Taken together these data suggest castration causes an increased uptake of substrates that are acted upon by CatD in lysosomes of principal cells and in the lumen by procathepsin D. These substrates may be derived from apoptotic cells noted in the lumen of proximal regions and possibly by degenerating sperm in distal regions of the epididymis of Ct animals. Exploring the mechanisms by which lysosomal enzymes are synthesized and secreted by the epididymis may help resolve some of the issues originating from epididymal dysfunctions with relevance to sperm maturation.

scholarly journals Specific alterations in levels of mannose 6-phosphorylated glycoproteins in different neuronal ceroid lipofuscinoses

1998 ◽  
Vol 334 (3) ◽  
pp. 547-551 ◽  
Author(s):  
David E. SLEAT ◽  
Istvan SOHAR ◽  
Premila S. PULLARKAT ◽  
Peter LOBEL ◽  
Raju K. PULLARKAT
Keyword(s):  
Lysosomal Enzyme ◽  
Neurodegenerative Disorders ◽  
Enzyme Activities ◽  
Lysosomal Enzymes ◽  
Vesicular Transport ◽  
Cell Types ◽  
Neuronal Ceroid Lipofuscinoses ◽  
Mannose 6 Phosphate ◽  
Normal Controls ◽  
Lysosomal Proteins

Mannose 6-phosphate (Man-6-P) is a carbohydrate modification that is generated on newly synthesized lysosomal proteins. This modification is specifically recognized by two Man-6-P receptors that direct the vesicular transport of the lysosomal enzymes from the Golgi to a prelysosomal compartment. The Man-6-P is rapidly removed in the lysosome of most cell types; however, in neurons the Man-6-P modification persists. In this study we have examined the spectrum of Man-6-P-containing glycoproteins in brain specimens from patients with different neuronal ceroid lipofuscinoses (NCLs), which are progressive neurodegenerative disorders with established links to defects in lysosomal catabolism. We find characteristic alterations in the Man-6-P glycoproteins in specimens from late-infantile (LINCL), juvenile (JNCL) and adult (ANCL) patients. Man-6-P glycoproteins in LINCL patients were similar to controls, with the exception that the band corresponding to CLN2, a recently identified lysosomal enzyme whose deficiency results in this disease, was absent. In an ANCL patient, two Man-6-P glycoproteins were elevated in comparison with normal controls, suggesting that this disease also results from a perturbation in lysosomal hydrolysis. In JNCL, total levels of Man-6-P glycoproteins were 7-fold those of controls. In general this was reflected by increased lysosomal enzyme activities in JNCL but three Man-6-P glycoproteins were elevated to an even greater degree. These are CLN2 and the unidentified proteins that are also highly elevated in the ANCL.

scholarly journals Localization of lysosomal and peroxisomal enzymes in the specific granules of rat intestinal eosinophil leukocytes revealed by immunoelectron microscopic techniques.

1984 ◽  
Vol 32 (3) ◽  
pp. 267-274 ◽  
Author(s):  
S Yokota ◽  
H Tsuji ◽  
K Kato
Keyword(s):  
Quantitative Analysis ◽  
Intestinal Mucosa ◽  
Cathepsin D ◽  
Lysosomal Enzymes ◽  
Protein A ◽  
Gold Complex ◽  
Double Labeling ◽  
Specific Granules ◽  
Acyl Coa Oxidase ◽  
Microscopic Techniques

Immunoelectron microscopic localization of lysosomal and peroxisomal enzymes in the eosinophil leukocytes of rat intestinal mucosa was studied by use of rabbit antibodies to the enzymes coupled to protein A-gold complex. Gold particle labeling for the lysosomal enzymes, beta-glucuronidase and cathepsin D, was present on specific granules, with a heavy concentration on their paracrystalline cores. The peroxisomal enzymes, acyl-CoA oxidase and catalase, were also found on these granules. The double labeling procedures using two different combination of anti-acyl-CoA oxidase and anti-beta-glucuronidase or anti-catalase and anti-cathepsin D revealed that these enzymes were simultaneously present in specific granules of the intestinal eosinophils. Quantitative analysis of the labeling on subcellular compartments confirmed that all enzymes examined are significantly localized within specific granules and that there is no significant labeling on other compartments such as the nucleus and cytoplasm. In the control sections incubated with an immunoglobulin G fraction from nonimmunized rabbits, no specific labeling was seen on the granules or other organelles. These findings indicate that enzymes which previously have been identified in some organs as lysosomal and in others as peroxisomal can be found together in eosinophil granules.

Development of the testis and epididymis of the Clun Forest ram

1971 ◽  
Vol 76 (3) ◽  
pp. 433-441 ◽  
Author(s):  
R. J. Colyer
Keyword(s):  
Body Weight ◽  
Rate Of Increase ◽  
Wide Range ◽  
Body Weights ◽  
Close Relationship ◽  
Subsequent Phase ◽  
Dimensional Growth ◽  
Left And Right ◽  
Ram Lambs

SUMMARYObservations were made on the development of the testes and epididymides of thirty-two Clun Forest ram lambs. There were no significant differences between the weights and volumes of the left and right testes and epididymides.The rate of increase in testicular and epididymal weights was linear up to a body weight of 46 lb (20·9 kg) followed subsequently by a significantly greater rate of increase at higher body weights. Similar patterns of growth occurred in relation to age, although at a given age there was a wide range of testicular and epididymal weights. There was a close relationship between the development of the testis and the epididymis at body weights greater than 46 lb (20·9 kg).There were two distinct phases in the dimensional growth of the testis. Increases in testicular length and breadth proceeded at much the same rate at testis weights of below 20 g. During the subsequent phase testicular length increased at a significantly greater rate than testis breadth.

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