Distribution of Cystatin C (γ-Trace), an Inhibitor of Lysosomal Cysteine Proteinases, in the Anterior Lobe of Simian and Human Pituitary Glands

Abstract

Cystatin C, a protein inhibitor of lysosomal cysteine proteinases, was demonstrated by immunohistochemical techniques to be present in most luteinizing hormone- (LH-)containing cells in simian and human adenohypophyses. Immunoreactivity of cystatin C was also found in simian adrenocorticotrophic hormone- (ACTH-)containing cells localized to an area corresponding to the pars intermedia but not in the ACTH-containing cells of the anterior pituitary lobe of monkey. No immunoreactivity of cystatin C was detected in the growth hormone- (GH-) and prolactin-containing cells of monkey and man.

Immunohistochemical characterization of the amyloid deposits and quantitation of pertinent cerebrospinal fluid proteins in hereditary cerebral hemorrhage with amyloidosis.

“…It is a potent inhibitor of the lysosomal cysteine proteinases cathepsin B, H, and L, 78 and has been suggested to play a regulatory role in the degradation of proteins and postribosomal processing of peptides. 32 Cystatin C occurs in all investigated human extracellular fluids. 23 The concentration of cystatin C in CSF is particularly high, and in normal adults the level in CSF is 5.5 times higher than that in blood plasma.…”

“…23 The concentration of cystatin C in CSF is particularly high, and in normal adults the level in CSF is 5.5 times higher than that in blood plasma. Cystatin C is present intracellularly in brain cortical neurons, 12 in the luteinizing-hormone-containing cells, and in certain ACTHcontaining cells of the adenohypophysis, 32 in the calcitonin-containing C-cells of the thyroid gland, 13 the glucagon-containing A-cells of the pancreatic islets, 14 and in the adrenal medulla. 13 Cystatin C is also found in nonhypersecreting pituitary adenomas.…”

Cystatin C: A New Renal Marker and Its Potential Use in Small Animal Medicine

“…In the early 1960s, a new protein was discovered in normal human cerebrospinal fluid and in the urine of patients with proteinuria . The highest concentration of this protein was measured in cerebrospinal fluid, followed by plasma, saliva, and urine, which suggested production in the central nervous system and catabolism by the kidney . The single polypeptide chain contained 120 amino acids, and the molecular mass was 13.260 kDa .…”

Association between serum cystatin C levels and the severity or potential risk factors of acute ischemic stroke

“…14 Cystatin C (also known as cystatin 3) is a potent inhibitor of lysosomal cysteine proteinase inhibitors in nucleated cells. 15,16 It is filtered by the renal glomerulus and metabolized by the proximal tubule. 17 Serum cystatin C concentration is shown to be a reliable biomarker for determining renal function and impairment.…”