Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022672 (acute tubular necrosis)
 2,175 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two protein sources (supplemented casein and lactalbumin), which were well-utilized by Syrian hamsters in previous 3-week experiments, were fed in long-term studies. Casein supplemented with methionine and cysteine was fed for 20 weeks at levels of 4, 20, and 40 g/100 g diet. The lowest level did not support normal growth and resulted in the highest mortality rate during the first 10 weeks of feeding. The higher levels caused increased mortality in females, in association with decreasing body weights between 16 and 20 weeks. Kidney weights and incidences of lower nephron nephrosis at 20 weeks were elevated in both sexes fed the 40 g/100 g levels of supplemented casein by comparison with the 10 g/100 g level. In a separate experiment, lactalbumin was fed for life at 10, 20, and 40 g/100 g diet levels, and its effects compared to those with a commercial diet. The lactalbumin diet supported somewhat slower growth rates, but improved survival when compared to commercial diet-fed groups. Survival was longest in both sexes fed the 20 g lactalbumin/100 g diet levels for life.
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PMID:Survival of hamsters fed graded levels of two protein sources. 714 9

In acute tubular necrosis, there are early transient increases in circulating and local bioactive hepatocyte growth factor (HGF) levels and renal HGF receptor (c-MET) gene expression. It has therefore been suggested that endogenous HGF may play a role in initiating renal repair. To test this hypothesis, changes in the levels, activity, and anatomic distribution of c-MET protein were characterized in relation to the onset and localization of DNA synthesis in kidneys of rats with ischemia-induced acute tubular necrosis. Whole-kidney c-MET protein levels were significantly increased in the injured kidneys 12 h after injury and rose to a maximum after 1 d, exceeding the control values by sevenfold. Eight days after injury, c-MET levels, although decreasing, were still elevated above control values. An increase in the levels of activated c-MET, i.e., tyrosine-phosphorylated c-MET, was also evident as early as 12 h after injury. Histologic analyses demonstrated that the increase in c-MET immunoreactivity was most marked in the most severely damaged nephron segments in the outer medulla. In injured proximal tubules, the receptor was redistributed from an apical location to an intracellular location. DNA synthesis was increased in the injured kidneys, especially in the outer medulla, where the increase in c-MET protein levels was most prominent. The increase in DNA synthesis was first detected 12 h after the initial increase in activated c-MET levels. It is concluded that the early increases in the levels of c-MET protein and activated receptor support the hypothesis that HGF participates in the initiation of renal regeneration. In addition, the persistent elevation of c-Met protein levels suggests that prolonged and even late treatment with HGF may be of therapeutic value
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PMID:Hepatocyte growth factor receptor in acute tubular necrosis. 1118 1

Hepatocyte growth factor and its receptor, Met, activate biological pathways necessary for repair and regeneration following kidney injury. The Met receptor is expressed in multiple cell types within the kidney, each of which is capable of regulating fibrotic responses. To specifically address the role of the Met receptor in the adult collecting duct during renal injury, a conditional knockout mouse (Met(fl/fl);HoxB7-Cre) was generated and tested using unilateral ureteral obstruction, a model of nephron injury, fibrosis, and repair. Following obstruction in these mice there was increased expression of collagens I and IV along with plasminogen activator inhibitor 1, a known regulator of matrix degradation, compared to ureteral obstructed non-flox littermates. There were trends toward increased interstitial fibrosis, infiltration of the interstitium, and acute tubular necrosis in the knockout mice despite similar degrees of hydronephrosis to the control littermates. The Met(fl/fl);HoxB7-Cre mice; however, had reduced tubular cell proliferation and kidney regenerative capacity after release of the obstruction, thus leading to diminished functional recovery. We suggest that Met receptor signaling in the collecting duct acts as a major regulator of cell survival and propagation of the repair process with a possible secondary role to diminish inflammatory and fibrotic responses.
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PMID:Deletion of the Met receptor in the collecting duct decreases renal repair following ureteral obstruction. 1967 27