Nephroprotective Effect of Leu-Ile-Lys Tripeptide in Experimental Diabetes Mellitus.

We studied the effect of tripeptide Leu-Ile-Lys on kidney function in rats with experimental diabetes mellitus modeled by single intraperitoneal administration of streptozotocin (65 mg/kg). The tripeptide was intragastrically administrated in a dose of 11.5 mg/kg from week 5 to week 8 of the pathological process. The concentrations of glucose, protein, and creatinine in the urine were measured before and then weekly throughout the experiment. In 8 weeks, the markers of activity of the free radical oxidation process (concentration of TBA-reactive substances, total prooxidant activity, and total antioxidant activity, as well as activities of catalase, superoxide dismutase, and glutathione peroxidase) were assayed and a morphological study was conducted. After administration of the tripeptide Leu-Ile-Lys for 4 weeks, glucose concentration in the urine decreases by 3-44 times (p<0.001) and protein concentration by 2.3-3.7 times (p=0.007). The concentration of TBA-reactive substances decreased by 1.3 times (p<0.001), and the total antioxidant activity increased by 2.3 times (p<0.001). Administration of the tripeptide Leu-Ile-Lys to animals with experimental diabetes mellitus led to significant improvement of the renal function against the background of significant alleviation of oxidative damage and an increase in the antioxidant protection of the renal tissues. Improvement of the morphofunctional state of tissues and cells of the renal glomerulus was confirmed histologically, in particular, an increase in the number of podocytes by 1.5 times was observed.

Experience of Using Tripeptide Leu-Ile-Lys for Experimental Therapy of Chronic 16-Week Oxalate Nephrolithiasis in Rats.

We studied the effect of tripeptide Leu-Ile-Lys on the course of chronic 16-week oxalate nephrolithiasis in rats modeled by administration of 1% ethylene glycol solution in drinking water for 16 weeks. The tripeptide Leu-Ile-Lys obtained by chemical synthesis (sample purity ≥98%) was administered intragastrically through a probe in a dose of 11.5 mg/kg in 1 ml saline. It was found that during tripeptide Leu-Ile-Lys significantly alleviated the course of experimental pathology, which was confirmed by characteristic biochemical and morphological indicators. We observed a decrease in the concentration of calcium ions by 4.4 times, weakening of oxidative stress in the renal tissue due to a decrease in the total prooxidant activity by 1.2 times, normalization of increased catalase activity, and reduction of superoxide dismutase activity by 2.4 times relative to disease control. Histological signs of nephrolithiasis were recorded in 9% cases (vs. 75% cases in disease control).

Effect of Tripeptide Leu-Ile-Lys on the Course of Experimental Nephrolithiasis.

We studied the effect of Leu-Ile-Lys tripeptide on the course of experimental oxalate nephrolithiasis modeled in rats by administration of 1% ethylene glycol solution instead of drinking water for 6 weeks. The Leu-Ile-Lys tripeptide obtained by chemical synthesis (purity ≥98%) was administered through a gastric tube (11.5 mg/kg in 1 ml saline). Administration of Leu-Ile-Lys tripeptide against the background of experimental oxalate nephrolithiasis significantly alleviated the course of experimental pathology, which was confirmed by typical biochemical and morphological changes: decrease in urinary activity of γ-glutamyltransferase (by 2.1 times in comparison with the initial level) and intensity of oxidative stress (the content of TBA-reactive products decreased by 1.3 times in comparison with that in untreated animals) and increase in glutathione peroxidase activity by 1.8 times; no histological signs of nephrolithiasis were found in animals treated with the tripeptide.

[The features of the pathologic changes in chronic oxalate stone disease after 16 week of experimental phase].

AIM: to study the pathologic features of chronic oxalate stone disease. MATERIALS AND METHODS: a model of the experimental oxalate stone disease was done in rats that drank the 1% ethylene glycol solution for 16 weeks. The pathologic analysis of the rats kidneys was done. RESULTS: After 16 weeks of oxalate stone disease modeling in all parts of kidneys the large crystals deposits were found, which plugged renal tubules. Moreover, purulent calculous pyelonephritis developed complicated by fibrosis.

Morphological Evaluation of the Influence of the Peptide Complex from Tissue of Porcine Kidneys on the Experimental Urolithiasis.

We performed morphological analysis of the effect of the peptide complex from porcine kidneys on the course of experimental urolithiasis modeled in rats by treatment with 1% ethylene glycol solution (in drinking water) for 6 weeks. The peptide complex obtained by acetic acid extraction was administered in a dose of 15 mg. Administration of the peptide complex to animals with experimental kidney stone disease leads to 100% destruction of large and medium stones to the "dust" granularity.

[Diurnal changes in the lysosomal enzyme activity of the liver of mice and rats]. / Sutochnye izmeneniia aktivnosti lizosomal'nykh fermentov v pecheni myshei i krys.

Lysosomal enzymes acid phosphatase, acid DNAase, acid RNAase cathepsin D,beta-galactosidase beta-glucuronidase were studied in mice and rat liver tissue within 3 days beginning from 4 o'clock a.m. at 4 hrs intervals. Activities of acid phosphatase, acid RNA ase in mice liver tissue and of cathepsin D in rat and mice liver tissues was higher at morning and day time than at evening and night. Alterations in enzymatic activity of non-sedimenting fraction of mice liver tissue correlated with that of total activity. In non-sedimenting fraction of rat liver tissue the enzymatic activity was altered only slightly. Within the second half of a day the enzymatic activity redistributed in the cells with an increase of the activity in non-sedimenting fraction, caused by labilization of lysosomal membranes.

[Effect of choriogonine on the enzymatic activity of lysosomes in the cirrhotic liver in the rat]. / Vliianie khoriogonina na fermentativnuiu aktivnost' lizosom v tsirroticheski izmenennoi pecheni krws.

Liver tissue cirrhosis, developed in rats after long-term administration of CCl4, led to distinct increase in activities of acid phosphatase, acid DNAase, cathepsin D, beta-galactosidase and beta-glucosidase. When the treatment with the hepatotropic toxins was stopped activity of lysosomal enzymes decreased slightly but was maintained at the high level. Within a day after a single administration of choriogonine distinct decrease as compared with the controls in activity of all the acid hydrolases studied was found. Within subsequent periods the lysosomal enzymes activity continued to decrease and within 2 months after the choriogonine treatment it was distinctly lower as compared with control animals.