Sialic acid supplementation ameliorates puromycin aminonucleoside nephrosis in rats.

Defects in sialylation are known to have serious consequences on podocyte function leading to collapse of the glomerular filtration barrier and the development of proteinuria. However, the cellular processes underlying aberrant sialylation in renal disease are inadequately defined. We have shown in cultured human podocytes that puromycin aminonucleoside (PAN) downregulates enzymes involved in sialic acid metabolism and redox homeostasis and these can be rescued by co-treatment with free sialic acid. The aim of the current study was to ascertain whether sialic acid supplementation could improve renal function and attenuate desialylation in an in vivo model of proteinuria (PAN nephrosis) and to delineate the possible mechanisms involved. PAN nephrotic rats were supplemented with free sialic acid, its precursor N-acetyl mannosamine or the NADPH oxidase inhibitor apocynin. Glomeruli, urine, and sera were examined for evidence of kidney injury and therapeutic efficacy. Of the three treatment regimens, sialic acid had the broadest efficacy in attenuating PAN-induced injury. Proteinuria and urinary nephrin loss were reduced. Transmission electron microscopy revealed that podocyte ultrastructure, exhibited less severe foot process effacement. PAN-induced oxidative stress was ameliorated as evidenced by a reduction in glomerular NOX4 expression and a downregulation of urine xanthine oxidase levels. Sialylation dysfunction was improved as indicated by reduced urinary concentrations of free sialic acid, restored electrophoretic mobility of podocalyxin, and improved expression of a sialyltransferase. These data indicate that PAN induces alterations in the expression of enzymes involved in redox control and sialoglycoprotein metabolism, which can be ameliorated by sialic acid supplementation possibly via its properties as both an antioxidant and a substrate for sialylation.

Yi Qi Qing Re Gao formula ameliorates puromycin aminonucleoside-induced nephrosis by suppressing inflammation and apoptosis.

BACKGROUND: Yi Qi Qing Re Gao (YQQRG) formula is a traditional Chinese herbal medicine used to treat chronic nephritis. This study was designed to evaluate the underlying mechanism in the use of YQQRG formula to treat nephrosis induced by puromycin aminonucleoside (PAN). METHODS: Thirty-six male Wistar rats were randomly divided into 3 groups of 12 rats each: a sham group, a vehicle-treated PAN model group (PAN), and a group treated with YQQRG (PAN + YQQRG). The PAN model was established by a single intravenous injection of PAN at a dose of 40 mg/kg body weight; rats in the sham group received the same volume of saline. Twenty-four hour urinary protein was measured 0, 3, 5, 10, and 15 days after the injection. The rats were sacrificed on day 10 and day 15 and the serum lipid profile examined. The renal cortex of each rat was stained with periodic acid-Schiff reagent and the pathologic alterations and ultrastructural changes were examined by transmission electron microscopy. In situ cell apoptosis was detected by a terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end-labeling (TUNEL) assay. Transcriptive levels of inflammatory markers and molecules associated with apoptosis were detected by a real-time polymerase chain reaction and expression of proteins was examined by either immunohistochemistry or Western blot analysis. RESULTS: YQQRG significantly decreased urinary protein level, and lowered serum lipid level. YQQRG also attenuated histologic lesions in the rat kidneys. Activation of inflammatory markers was largely restored by the administration of YQQRG. TUNEL assay showed that YQQRG decreased the number of apoptotic cells. Both mRNA and protein levels of caspase-3 were significantly reduced in the group treated with YQQRG, whereas expression of the Bcl-2 protein increased in the YQQRG group. CONCLUSIONS: YQQRG alleviated kidney injury in PAN-treated rats, possibly through anti-inflammatory and anti-apoptotic effects.

[Protective Effects of Different Extracts of Imperatae Rhizoma in Rats with Adriamycin Nephrosis and Influence on Expression of TGF-ß1, and NF-κB p65].

OBJECTIVE: To study the protective effect of Imperatae Rhizoma extract on renal tissues in rats with Adriamycin nephrosis, and to explore the possible mechanism. METHODS: The nephrosis model was induced by adriamycin 6.5 mg/kg intravenously in rats. The rats were randomly divided into seven groups, including normal group, model group, predisone group, petroleum ether groups, ethyl acetate group ,alcohol group, and water parts group, and treated for eight weeks. The protein content of 24 hours urine excretion was tested respectively by automatic biochemistry analyzer each week. After eight weeks, BUN, CRE, TCHO, TG, TP and ALB in serum were examined by automatic biochemistry analyzer. The TNF-α in serum was measured by ELISA. The expression of TGF-ß1, and NF-κB p65 in renal tissues were detected by immunohistochemistry respectively. The pathological changes in the renal were observed by light microscope. RESULTS: Compared with the model group ,the proteinuria of the rats in ethyl acetate group obviously reduced at the 6th, 7th, 8th week, the content of TNF-α in serum and the expression of TGF-ß1, and NF-κB p65 in renal tissues significantly reduced, but the content of TP and ALB in serum were increased obviously. In the alcohol and water parts groups ,the level of TG in serum and the protein content of 24 hours urine excretion of the 6th and 7th week were significantly decreased. The ethyl acetate, alcohol and water parts groups ameliorated the changes of pathology in renal. CONCLUSION: The different extracts of Imperatae Rhizoma had different protective effect in rats with adriamycin nephrosis, and the effect of ethyl acetate group was more stronger than that of other groups. The mechanism may be related to reducing the expression of NF-κB p65 and TGF-ß1, and the content of TNF-α inrenal tissues of rats.

The RIP1-kinase inhibitor necrostatin-1 prevents osmotic nephrosis and contrast-induced AKI in mice.

The pathophysiology of contrast-induced AKI (CIAKI) is incompletely understood due to the lack of an appropriate in vivo model that demonstrates reduced kidney function before administration of radiocontrast media (RCM). Here, we examine the effects of CIAKI in vitro and introduce a murine ischemia/reperfusion injury (IRI)-based approach that allows induction of CIAKI by a single intravenous application of standard RCM after injury for in vivo studies. Whereas murine renal tubular cells and freshly isolated renal tubules rapidly absorbed RCM, plasma membrane integrity and cell viability remained preserved in vitro and ex vivo, indicating that RCM do not induce apoptosis or regulated necrosis of renal tubular cells. In vivo, the IRI-based CIAKI model exhibited typical features of clinical CIAKI, including RCM-induced osmotic nephrosis and increased serum levels of urea and creatinine that were not altered by inhibition of apoptosis. Direct evaluation of renal morphology by intravital microscopy revealed dilation of renal tubules and peritubular capillaries within 20 minutes of RCM application in uninjured mice and similar, but less dramatic, responses after IRI pretreatment. Necrostatin-1 (Nec-1), a specific inhibitor of the receptor-interacting protein 1 (RIP1) kinase domain, prevented osmotic nephrosis and CIAKI, whereas an inactive Nec-1 derivate (Nec-1i) or the pan-caspase inhibitor zVAD did not. In addition, Nec-1 prevented RCM-induced dilation of peritubular capillaries, suggesting a novel role unrelated to cell death for the RIP1 kinase domain in the regulation of microvascular hemodynamics and pathophysiology of CIAKI.

[Effect of modified sijunzi decoction on the bone metabolism of adriamycin induced nephropathy rats].

OBJECTIVE: To explore the effect of Modified Sijunzi Decoction (MSD) on the bone metabolism of prednisone intervened adriamycin-induced nephropathy rats. METHODS: The adriamycin-induced nephropathy rat model was prepared. Totally 50 SD rats were randomly divide into five groups, i.e., the model group, the hormone group, the Chinese medicine (CM) group, the CM + hormone group, and the normal control group. The 24-h urine samples were collected on the 7th, 21st, and 35th day after modeling. The 24-h urine protein was measured by biuret colorimetry. Serum levels of osteoprotegerin (OPG), receptor activator of nuclear factor-kappaB ligand (RANKL), osteocalcin (BGP), and tartrate-resistant acid phosphatase (TRACP) were determined by ELISA. Expressions of OPG and RANKL in the tibia tissue were detected using real-time quantitative PCR and Western blot. RESULTS: (1) Compared with the normal control group, the 24-h urine protein increased in each group on the 7th, 21st, and 35th day (P < 0.05, P < 0.01). Compared with the model group, the 24-h urinary protein decreased in the hormone group and the CM + hormone group (P < 0.05, P < 0.01). The decrement was more obvious along with the treatment time went by (P < 0.05, P < 0.01). There was statistical difference in the reduction of urine protein on the 35th day between the CM group and the model group (P < 0.05). (2) Compared with the 21st-day of the same group, the serum levels of TRACP and RANKL increased (P < 0.05, P < 0.01). Compared with the model group, the serum levels of the TRACP and RANKL increased (P < 0.05, P < 0.01), OPG and BGP decreased (P < 0.05, P < 0.01) in the hormone group. Compared with the CM group at the same period, serum OPG level decreased and the RANKL level increased in the hormone group and the CM + hormone group (P < 0.05, P < 0.01). Besides, the serum level of TRACP increased and BGP decreased (P < 0.05, P < 0.01). Compared with the hormone group at the same period, OPG and BGP increased (P < 0.05, P < 0.01), RANKL decreased (P < 0.01) in the CM + hormone group. On the 35th day TRACP decreased (P < 0.01). (3) Compared with the normal group, mRNA expressions of OPG and RANKL on the 21st day increased (P < 0.05, P < 0.01), mRNA expressions of OPG and RANKL on the 35th day decreased in the model group (P < 0.01). Compared with the CM group at the same period, OPG mRNA expression decreased (P < 0.01) and RANKL mRNA expression increased in the hormone group (P < 0.05). OPG mRNA expression decreased in the CM +hormone group (P < 0.05). (4) Compared with the hormone group on the 21st day, the OPG level decreased and the RANKL protein increased (both P < 0.05). RANKL decreased in the CM + hormone group (P < 0.05). Compared with the model group at the same period, OPG decreased and RANKL increased in the hormone group (P < 0.01). Compared with the CM group at the same period, OPG decreased (P < 0.01), RANKL increased (P < 0.01) in the hormone group and the CM + hormone group. Compared with the hormone group at the same period, OPG increased and RANKL decreased in the CM + hormone group (both P < 0.01). CONCLUSIONS: Prednisone could induce osteoporosis through the OPG/RANKL/RANK pathway. MSZ could slow down the formation of prednisone-induced osteoporosis through promoting osteoblast differentiation, and inhibiting osteoclastogenesis.

[Effects of Chinese herbal medicine Huaiqihuang Granule on nephrin and podocin expressions in renal tissues of rats with adriamycin-induced nephrosis].

OBJECT: To investigate the effects of Huaiqihuang Granule, a compound Chinese herbal medicine, on expressions of nephrin and podocin of slit diaphragm of glomerular podocytes in rats with adriamycin-induced nephrosis and to explore the mechanism in reducing the proteinuria. METHODS: Twenty SD rats were randomly divided into five groups: control group, model group, glucocorticoid group, Huaiqihuang Granule group and Huaiqihuang Granule plus glucocorticoid group. The 24-hour urine was collected 7, 14, 21 and 28 days after adriamycin injection respectively to measure 24-hour urinary protein, and all rats were sacrificed after 28-day treatment. Pathological changes in renal tissues were observed under a light microscope and an electron microscope. Expressions of nephrin and podocin mRNAs in renal cortex were determined by real-time polymerase chain reaction, and protein levels of nephrin and podocin were detected by Western blotting. RESULTS: (1) In the model group and the treatment groups, the level of urinary protein increased significantly from the 14th day. (2) Under the light microscope, inflammatory cells and slight fibroplasia were found in renal interstitium of the model group, but there were less inflammatory cells in renal interstitium in the intervention groups than in the model group. Under the electron microscope, 29 days after adriamycin injection, extensive fusion of foot processes was observed. (3) The expressions of nephrin and podocin were higher in treatment groups than in the model group. (4) Proteinuria level was negatively correlated with the expressions of nephrin mRNA and nephrin and podocin proteins. CONCLUSION: The above results indicate that Huaiqihuang Granule can maintain the integrity of the slid diaphragram in podocyte, alleviate the lesion of glomerular filtration membrane, and decrease the proteinuria by up-regulating the expressions of nephrin and podocin. Huaiqihuang Granule plus glucocorticoid maybe has better effects than glucocorticoid alone.

[Effects of Qufengtongluo Recipe on podocin mRNA expression and podocyte morphology in rats with adriamycin-induced nephropathy].

OBJECTIVE: To observe the effects of Qufengtongluo Recipe (QFTLR) on the expression of podocin mRNA and podocyte morphology in rats with adriamycin-induced nephropathy (AN), and explore the possible mechanism mediating the therapeutic effect of QFTLR on nephropathic proteinuria. METHODS: SD rats were randomized into normal control group, AN model group (established by a single injection of adriamycin via the tail vein), and 3 intervention groups with QFTLR, prednisone, or benazepril treatment. After the corresponding treatments, the expression of podocin mRNA in the renal tissues was detected by RT-PCR methods, and the morphological changes of the podocytes were examined by electron microscope. RESULTS: Compared with the normal control group, the AN model group showed significantly lowered expressions of podocin mRNA (P<0.01) with reduced podocytes and widening, fusion or even absence of the foot processes (FP). Intervention with QFTLR significantly increased the expression of podocin mRNA (P<0.01) and the number of podocytes, and obviously lessened the structural changes of the FP. CONCLUSION: QFTLR can produce therapeutic effect against nephropathic proteinuria possibly by up-regulating the expression of podocin mRNA and improving the morphological changes of the podocytes.

Protective effects of Huang Qi Huai granules on adriamycin nephrosis in rats.

Huang Qi Huai (HQH) granules, a mixture of Chinese herbs, contains trametes robiniophila murr, wolfberry fruit, and Polygonatum. We investigated the mechanism of the protective effects of HQH on adriamycin nephrosis (ADR) in rats. Adriamycin nephrotic rats were induced by a single dose of 5 mg/kg adriamycin. For the HQH-treated adriamycin nephrosis group, 1 day after treatment with 5 mg/kg adriamycin, the rats were administered once-daily oral gavage of 2 mg/kg HQH for 15 days. All the rats were killed at day 15. Histological changes were observed by light microscopy and transmission electron microscope. Nephrin and podocin expression levels were measured by real-time RT-PCR and Western blot. Proteinuria was measured by the Bradford protein assay. Serum TNF-α and IL-1ß levels were evaluated by ELISA. Macrophage infiltration was detected by immunohistochemistry and immunoblotting, respectively. ADR rats showed heavy proteinuria, podocyte and tubulointerstitial injury, macrophage infiltration, and increased levels of serum cytokines TNF-α and IL-1ß. HQH significantly ameliorated the adriamycin-induced renal injury. These data were validated in the cultured podocytes. The podocytes were treated by adriamycin in the presence or absence of HQH and nephrin and podocin expression and TNF-α and IL-1ß synthesis and secretion were determined by real-time RT-PCR, immunoblotting, and ELISA, respectively. Adriamycin significantly reduced nephrin and podocin expression, which was significantly restored by the treatment of HQH. HQH treatment inhibited adriamycin-induced TNF-α and IL-1ß expression. Our findings suggest that HQH significantly reduces proteinuria, prevents podocyte injury, and ameliorates tubulointerstitial damage. Inhibition of inflammatory cytokine expression and macrophage infiltration may be the protective mechanism of HQH.

[Effects of Qufengtongluo recipe on proteinuria and glomerular filtration membrane in rats with adriamycin-induced nephropathy].

OBJECTIVE: To assess the therapeutic effect of Qufengtongluo (QFTL) recipe against proteinuria and glomerular filtration membrane damage in rats with adriamycin-induced nephropathy (AN). METHODS: Fifty-six SD rats were randomized into normal control (A) and AN model groups. In the AN model group, the rat AN models established by a single intravenous injection of adriamycin via the tail vein were subdivided into model (B), QFTL recipe (C), prednisone (D), and benazepril (E) groups 3 weeks after adriamycin injection. The 24-h urinary protein level was measured and the expression of anionic sites on the filtration membrane was evaluated using electron microscope with PEI staining. Nephrin expression on the glomerular filtration membrane was detected with indirect immunofluorescence assay. RESULTS: Compared with group A, the model group showed significantly increased level of 24-h urinary protein (P<0.01), suggesting successful establishment of the AN model. Treatment with QFTL recipe obviously lowered the 24-h urinary protein (P<0.01), and increased the expression of anionic sites and nephrin on the glomerular filtration membrane in the AN rats (P<0.01). CONCLUSION: QFTL recipe can effectively decrease 24-h urinary protein, improve the symptoms, and up-regulate the expressions of anionic sites and nephrin on the glomerular filtration membrane in rats with AN.

[Mechanism of combined treatment with Shenkangling Decoction and prednisone in rats with adriamycin-induced nephropathy].

OBJECTIVE: To study the mechanism of Shenkangling (SKL), a compound traditional Chinese herbal medicine, combined with prednisone in treating adriamycin-induced nephropathy in rats. METHODS: Sixty-six SD male rats were randomly divided into normal control group, untreated group, prednisone group, SKL group and SKL plus prednisone group. Except the normal control group, rats were injected once via caudal vein with adriamycin (5.5 mg/kg) to induce nephropathy. Then, the rats were administered with prednisone, SKL, prednisone plus SKL or distilled water for 3 weeks, respectively. After harvest, 24-hour urine protein excretion, tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) contents in serum, and content of nuclear transcription factor-kappa B (NF-kappaB) p65 in mononuclear cells were determined, and correlation analysis among these parameters was performed. The content of NF-kappaB p65 was assayed with the patented method of Active Motif; TNF-alpha was assayed with enzyme-linked immunosorbent assay, and the content of NO was assessed by the method of nitrate reductase. The change of foot process in renal glomerulus was observed under an electron microscope. RESULTS: When the rats were administered with prednisone, SKL correspondingly, the contents of NF-kappaB p65, TNF-alpha and NO as well as 24-hour urine protein excretion were lower than those in the untreated group (P<0.01), and the fusion of foot process only recovered partially. Compared with other treated groups, the contents of NF-kappaB p65 and NO as well as 24-hour urine protein excretion were significantly decreased in SKL plus prednisone group (P<0.01, P<0.05), and the fusion of foot process recovered mostly also. There was no interaction between SKL and prednisone in decreasing the content of TNF-alpha. CONCLUSION: Renal injury can be postponed and improved when treated with SKL plus prednisone; it may contribute to the depression of abnormal activation of NF-kappaB, and the inhibition of production of TNF-alpha and NO.

[Alteration of renal hemodynamic in adriamycin-induced nephrosis rats administrated with Wulingsan].

OBJECTIVE: To investigate the effect of traditional classical compound Wulingsan on renal hemodynamic in rats with adriamycin (ADR)-induced nephrosis. METHOD: After establishing a model of rats with adriamycin-induced nephrosis, we administrated wulin-san to the ADR rats via oral gavage for four weeks and measured mean arterial blood preasure (MABP) with manometer. Renal clearance of paraaminohippuric acid (PAH) and inulin were detected, then renal plasma flow (RPF) and glomerular filtration rate (GFR) were calculated. Renal vascular resistance (RVR) was calculated as the division of MABP by RPF. Renal endothelin (ET) and angiotensin II (Ang II) were detected with radioimmunity assay kits, and nitrous oxide (NO) was detected with biochemical kits. RESULT: There was no significant change of GFR in ARD rats, but RPF and NO were decreased, which accompanied by enhanced RVR, ET and Ang II. RPF was increased in the administrated rats, in company with RVR, ET and Ang II decreased, whereas NO was not influenced after the administration. CONCLUSION: Wulingsan can improve the renal hemodynamic in ADR rats, at least in part by modulating the levels of vasoactive factor.

Effect of grape seed extract on puromycin-aminonucleoside-induced nephrosis in rats.

Recent studies indicate that an excessive production of oxidants plays an important role in the pathogenesis of glomerular disease. Grape seed extract (GSE) is a potent antioxidant, and the aim of this pilot study was to evaluate its effect on puromycin-aminonucleoside (PAN)-induced nephrosis in rats. Fifty Sprague-Dawley rats were divided into five groups. Groups 1 and 2 rats received water from day 0 to day 30. Rats in groups 3, 4, and 5 received GSE at 10 mg/100g of body weight (BW), which was started on day 0, 6, and 3 of the experiment, respectively. In group 5 animals the GSE dose was increased (40 mg/100g BW) on day 9. Intraperitoneal dextrose (group 1) or PAN 15 mg/100g BW (groups 2-5) was administered on day 3. Urine and blood specimens were collected at regular intervals, and the comparison between the various groups was made by analysis of variance (ANOVA). Rats in all study groups (groups 3-5) showed a decrease in urine protein and serum cholesterol and triglyceride levels, which was statistically significant in group 3 animals. No significant changes were noted in serum albumin and creatinine levels. In conclusion, GSE administration decreases urine protein excretion and serum cholesterol and triglyceride levels in rats with PAN-induced nephrosis.

Evaluation of the pituitary-testicular function during experimental nephrosis.

To investigate the pituitary-testicular function in nephrotic rats, a sequence of experiments was undertaken in adult male rats after a single dose of puromycin aminonucleoside (PAN). Endocrine modifications were evaluated chronologically throughout the experimental disease in order to determine the appearance of hormone alterations which lead to the axis dysfunction. Serum concentration of LH, FSH, androstenedione, total and free testosterone, estradiol as well as urine testosterone were measured by specific RIAs on days 3, 7 and 10 after treatment on nephrotic and control groups. Prolactin was also evaluated on day 10. Likewise, total weight of various androgen responsive tissues from both groups was recorded, and the number of androgen receptor (AR) binding sites were determined. To know the functional status of the hipophyseal-testicular unit, groups of nephrotic and control rats were stimulated with LHRH (300 ng/100 g b.w.) or with one or four doses of hCG (8 UI), respectively. Additionally, the relative in vitro biological activity of FSH from nephrotic and control rats before and after LHRH stimulus was determined. The results from the hormonal profile revealed clear endocrine disorders characterized by a progressive diminution of all serum hormones except prolactin and urine testosterone, which remained unmodified. The weight of the main androgen responsive tissues, the ventral prostate and the seminal vesicle, decreased parallelly to androgen diminution. The binding analysis of AR shows a significant elevation of the available androgen sites in all analyzed tissues except kidney and hypothalamus. The secretion of LH and FSH from nephrotic animals after LHRH administration was lower than that from intact animals at the registered times. Interestingly, the biological activity of FSH from nephrotic rats was not detectable at both, before and after LHRH administration. Testicular response to hCG stimuli, in terms of testosterone synthesis was not significantly different in the two groups analyzed with respect to the intact animals. By contrast, no response was observed in terms of estradiol production at either one or four doses of hCG. On the whole, the results presented herein allow us to conclude that experimental nephrosis has a harmful effect on the pituitary-testicular axis, and strongly suggests that the endocrine dysfunction is initiated at the hypophyseal level; even though a specific testicular damage is also present.

[Effect of shenfukang on nephropathy rats induced by adriamycin].

UNLABELLED: Adriamycin-induced nephropathy (AIN) model in rats (mainlining 7.5 mg/kg avoirdupois adiramycine) was adopted to explore the effect of Shenfukang (SFK). The results showed that SFK could remarkably reduce the content of urine protein, cholesterol, creatinine and urinary nitrogen in serum, MDA in serum and renal cortex of AIN model rats. And SFK also could increase the content of album and golbulin in serum, the activities of SOD in serum and renal cortex of AIN model rats. CONCLUSION: SFK played an important role on AIN.

[Experimental study of compound salvia injection in preventing and treating chronic nephrotoxicity induced by cyclosporin A in rats].

OBJECTIVE: To explore the mechanism of protective effect of Compound Salvia Injection (CSI) on experimental cyclosporin A induced nephrotoxicity. METHODS: Rats were on low-salt diet and cyclosporin A (CsA) was administered once a day through gastrogavage at dosage of 30 mg/kg.d for 28 days. Expression of the mRNA for intrarenal transforming growth factor-beta 1 (TGF-beta 1) and renin was measured by reverse transcription-polymerase chain reaction (RT-PCR). Intrarenal expression of TGF-beta 1 and Collagen IV was determined by immunohistochemical assays. The effects of CSI on these changes were also evaluated. RESULTS: Chronic CsA-induced nephropathy might be correlated to TGF-beta 1 and renin mRNA up-regulation as well as matric proteins accumulation in interstitium. CSI could reduce these changes. CONCLUSION: Decreased CsA-related TGF-beta 1 and renin upregulation expression and accumulation of matrix proteins in the kidney might be related to the protective mechanism of CSI on CsA-induced chronic nephrotoxicity.

Role of ticlopidine on adriamycin-induced nephropathy.

The effect of ticlopidine on rats with adriamycin nephropathy was observed during 26 weeks. In the ticlopidine-treated nephrotic animals (TNG), proteinuria was less than in the untreated nephrotic animals (NG), but this difference was significant only at week 6 (TNG = 47.27 +/- 16.52 versus NG = 100.08 +/- 13.83 mg/24 h, p < 0.01) and week 26 (TNG = 157.00 +/- 28.73 versus NG = 217.00 +/- 21.73 mg/24 h, p < 0.01) after ADR injection. NG presented severe tubulointerstitial abnormalities with a tubulointerstitial lesion index of 3+. No difference in glomerular lesions was observed among the groups (NG median = 6%, TNG median = 4% and TCG median = 2%). The tubulointerstitial lesion index of TNG was less intense (median = 2+) but not different from those of the control groups (CG median = 1+; TCG median = 0+) nor NG (median = 3+). We concluded that the treatment with ticlopidine produced some partially beneficial effects but did not prevent the development of adriamycin-induced nephropathy.

Effect of the in vivo catalase inhibition on aminonucleoside nephrosis.

Reactive oxygen species have been involved in the pathophysiology of puromycin aminonucleoside (PAN)-nephrosis. The role of H2O2 in these rats may be studied modulating the amount or activity of catalase, which breakdowns H2O2 to water and oxygen. To explore the role of H2O2 in this experimental model, we studied the effect of the in vivo catalase inhibiton with 3-amino-1,2,4-triazole (ATZ) on the course of PAN-nephrosis. Four groups of rats were studied: control rats (CT group), PAN-injected rats (PAN group), ATZ-injected rats (ATZ group), and ATZ- and PAN-injected rats (ATZPAN group). Rats were placed in metabolic cages to collect 24 h urine along the study, ATZ (1 g/kg) was given 24 h before PAN injection (75 mg/kg), and the proteinuria was measured on days 0, 2, 4, 6, 8, and 10. Proteinuria started before (day 4) and was significantly higher on days 6, 8, and 10 in the ATZPAN group than in the PAN group. On day 10, hypercholesterolemia was significantly higher in the ATZPAN group than in the PAN group. These data indicate that the in vivo catalase inhibition magnifies PAN-nephrosis, suggesting that H2O2 is produced in vivo and involved in the renal damage in this experimental disease.

Probable toxicosis in cattle in Israel caused by the oak Quercus calliprinos.

A probable outbreak of oak (Quercus calliprinos) toxicosis in a herd of beef cattle--heifers and first-calving cows--grazing in the Judean foothills of Israel is described. Toxicosis probably occurred because of the consumption of oak leaves and buds during a period of pasture scarcity without any feed supplementation. A progressive syndrome of wasting, dullness, anorexia, polyuria, nephrosis, constipation and recumbency, culminating in death, was seen. A high mortality rate of 83% (38/46 animals) was noted. The clinical-pathological findings revealed increases in blood urea, creatinine, aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), creatine kinase (CK), lactate dehydrogenase (LDH) and inorganic phosphorus. Decreases were found in alkaline phosphatase (ALP), total serum protein, albumin (ALB), triglyceride (TG), calcium (Ca), magnesium (Mg), sodium (Na) and chloride (CI). The main pathological findings were severe nephrosis, chronic interstitial nephritis, and occasional intestinal ulceration. On the basis of epidemiology, clinical signs, clinical-pathological and pathological findings and renal histology, a tentative diagnosis of oak toxicosis was made.

Effect of intravenous calcium administration on gentamicin-induced nephrotoxicosis in ponies.

OBJECTIVE: To determine whether supplemental i.v. calcium administration would attenuate or prevent gentamicin-induced acute renal failure, defined as an increase in serum creatinine concentration > or = 50% above baseline. ANIMALS: 10 healthy pony mares. PROCEDURE: Pony mares were randomly assigned to receive calcium at a dosage of 20 mg/kg of body weight or saline solution i.v., twice daily for 14 days. All pony mares received gentamicin at a dosage of 20 mg/kg i.v. every 8 hours for 14 days. Gentamicin pharmacokinetic, serum biochemical, and urinalysis data were measured every other day for the 14-day study period. Renal histologic examination was performed, and results were scored at the end of the 14-day period. RESULTS: 4 of 5 mares not receiving calcium supplementation developed acute renal failure. Only 1 of the 5 mares receiving calcium supplementation developed acute renal failure. Over the course of the study, pony mares receiving calcium supplementation had significantly fewer changes in urinalysis variables, and significantly less microscopic renal damage. CONCLUSION: Daily i.v. administration of calcium attenuated gentamicin-induced acute renal failure. CLINICAL RELEVANCE: Calcium supplementation may help diminish the risk of acute renal failure associated with aminoglycoside antibiotics.