Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.1 (aspartate aminotransferase)
 21,665 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Indoxyl sulfate, a uremic toxin, is accumulated in the serum of chronic kidney disease (CKD) patients. A part of the dietary protein-derived tryptophan is metabolized into indole by tryptophanase in intestinal bacteria. Indole is absorbed into the blood from the intestine, and is metabolized to indoxyl sulfate in the liver. Indoxyl sulfate is normally excreted into urine. In CKD, however, an inadequate renal clearance of indoxyl sulfate leads to its elevated serum levels. The oral adsorbent AST-120 reduces the serum levels of indoxyl sulfate by adsorbing indole in the intestines and stimulating its excretion into feces. I have proposed a protein metabolite theory by which endogenous protein metabolites such as indoxyl sulfate play a significant role in the progression of CKD. A progressive decline in the glomerular filtration rate leads to increased serum levels of endogenous protein metabolites such as indoxyl sulfate, and to the adverse effects of their overload on the remnant nephrons. Indoxyl sulfate stimulates progressive both tubulointerstitial fibrosis and glomerular sclerosis by increasing the expression of transforming growth factor-beta1, a tissue inhibitor of metalloproteinase-1 and proalpha1 (I) collagen, leading to a further loss of nephrons. AST-120 delays the progression of CKD by removing serum indoxyl sulfate. Moreover, indoxyl sulfate induces oxidative stress in tubular cells, mesangial cells, vascular smooth muscle cells, endothelial cells and osteoblasts as well as stimulating aortic calcification in hypertensive rats, it is also involved in the progression of CKD, cardiovascular disease (CVD) and osteodystrophy. Thus, the removal of indoxyl sulfate by AST-120 ameliorates the progression of not only CKD, but also of CVD and osteodystrophy.
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PMID:Uremic toxicity of indoxyl sulfate. 2022 98

An 8-yr-old, captive, female golden lion tamarin ( Leontopithecus rosalia ) with a 6-yr history of hyperbilirubinemia was examined for inappetence and weight loss. Physical examination and blood pressure monitoring under anesthesia revealed hypothermia and hypotension, and blood work revealed hypoglycemia, markedly elevated liver enzymes, including serum alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase, and confirmed the hyperbilirubinemia. A complete blood count suggested chronic lymphoid leukemia. The animal's condition deteriorated during recovery, and the animal died despite aggressive treatment. Grossly, there was micronodular cirrhosis of the liver, severe icterus, and diffuse osteopenia of all examined bones. Microscopic examination of the liver confirmed the micronodular cirrhosis and bone lesions were compatible with diffuse osteopenia and osteomalacia. This brief communication presents a case of chronic liver disease and lesions indicative of metabolic bone disease, also known as hepatic osteodystrophy. To the authors' knowledge, this is the first documented case of hepatic osteodystrophy in the veterinary literature.
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PMID:HEPATIC OSTEODYSTROPHY IN A GOLDEN LION TAMARIN (LEONTOPITHECUS ROSALIA). 2769 75

Indoxyl sulfate is a uremic toxin, and cannot be removed efficiently by hemodialysis due to its protein-binding. Indoxyl sulfate induces cellular dysfunction by producing reactive oxygen species (ROS) such as superoxide by activating nicotinamide adenine dinucleotide phosphate oxidase, and by activating aryl hydrocarbon receptor through its uptake via organic anion transporters (OAT1 and OAT3). Indoxyl sulfate shows toxic effects on a variety of cells such as renal proximal tubular cells, glomerular mesangial cells, vascular smooth muscle cells, vascular endothelial cells, cardiomyocytes, cardiac fibroblasts, monocytes, osteoblasts, osteoclasts, and myocytes. Indoxyl sulfate stimulates the progression of chronic kidney disease (CKD), cardiovascular disease (CVD), osteodystrophy, and sarcopenia. The carbon adsorbent AST-120 might be useful to delay the progression of not only CKD but also CVD, osteodystrophy, and sarcopenia by adsorbing its precursor, indole, in the intestines, and consequently reducing the serum levels of indoxyl sulfate. In this review, the author provides an overview on the current status of knowledge on the effects of AST-120 on uremic toxins, CKD animals, CKD patients, and CKD patients with CVD, and safety of AST-120. A large clinical study (EPPIC-1 and EPPIC-2) has failed to demonstrate the efficacy of AST-120 on the progression of CKD. However, the post-hoc subgroup analysis suggested that AST-120 might delay the progression of CKD patients. Further clinical studies are required to demonstrate the clinical efficacy of AST-120 on the progression of CKD by administering AST-120 only to those patients with progressive CKD and good compliance.
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PMID:The role of carbon adsorbent in the conservative management of chronic kidney disease. 2799 Jul 91