Single Intravenous Injection Of Adriamycin Research Articles

P2X7R antagonist protects against renal injury in mice with adriamycin nephropathy.

Activation of the purinergic P2X7 receptor (P2X7R) has been associated with the development of experimental nephritis. Therefore, the current study aimed to explore the mechanism of P2X7R in renal injured mice with adriamycin (ADR) nephropathy. The protective effect of a P2X7R antagonist on the kidneys of mice with ADR nephropathy was also evaluated. Nephropathy was induced by a single intravenous injection of ADR (10.5 mg/kg). A total of 6 h before the model was established, the P2X7R antagonist A438079 (100, 200 and 300 µmol/kg) was injected into the mice, which was subsequently administered daily for 1 week by intraperitoneal injection. Subsequently, all mice were sacrificed, after which blood, 24 h-urine and the kidneys were collected. The levels of albumin (ALB) and total cholesterol (TC) in the serum, along with urine protein content at 24 h were determined using an automatic biochemical analyzer. The levels of IL-1β and IL-18 were additionally detected in the renal tissues by ELISA. Moreover, the expression of P2X7R, oxidized (ox)-low density lipoprotein (LDL), C-X-C motif chemokine ligand 16 (CXCL16), Bax, caspase-3 and NLRP3 in renal tissues was detected by immunohistochemistry. Apoptosis in the renal tissues was observed using the TUNEL assay. The results demonstrated that compared with the control group, decreased weight, increased proteinuria, decreased serum ALB and increased serum TC was observed in the ADR group. The expression of IL-1β, IL-18, P2X7R, ox-LDL, CXCL16, Bax, caspase-3 and NLRP3, as well as cellular apoptosis in the renal tissues of the ADR group, was significantly increased in the ADR group compared with the control. However, compared with the ADR group, the changes in all indices in the ADR + A438079 groups were attenuated. Overall, P2X7R, ox-LDL and CXCL16 may be associated with ADR nephropathy, while inhibition of P2X7R may reduce the expression of ox-LDL by downregulating the CXCL16 pathway to alleviate kidney injury in mice with ADR nephropathy. Furthermore, activated P2X7R may promote the release of inflammatory cytokines IL-1β and IL-18 through the downstream P2X7R/NLRP3 pathway and upregulate the expression of Bax and caspase-3 to promote apoptosis, which participates in the process of ADR nephropathy. Inhibiting P2X7R may also reduce the release of IL-1β and IL-18 by downregulating the P2X7R/NLRP3 pathway, downregulating the expression of Bax and caspase-3, and reducing apoptosis, thereby alleviating kidney injury in mice with ADR nephropathy.

MicroRNA-206 and its down-regulation of Wilms’Tumor-1 dictate podocyte health in adriamycin-induced nephropathy

Background: Focal segmental glomerulosclerosis (FSGS) is a frequent and severe glomerular disease characterized by destabilization of podocyte foot processes. Emerging evidence suggests that microRNAs play crucial roles in podocyte homeostasis. The aim of the present study was to determine the role of miR-206 in podocyte injury and to elucidate the mechanisms responsible for the damage to podocyte. Methods: FSGS nephropathy model was induced by a single intravenous injection of Adriamycin (ADR) in BALB/c mice and the levels of proteinuria were measured on week of 1,3,5. The conditionally immortalized mouse podocyte cell line 5 was either transfected with microRNA mimics or negative control. Real-time PCR analysis was conducted to demonstrate the microRNA level in the glomeruli. Expression of Wilms’ tumor-1 (WT1) and synaptopodin were detected by immunofluorescence and western blotting. Results: The results revealed that miR-206 was up-regulated in ADR nephropathy mice, which led to severe podocyte injury and inhibited the expression of WT1 and synaptopodin. Using luciferase reporter assays, WT1 was identified as a target gene of miR-206. In vitro, over expression of miR-206 induced WT1 and synaptopodin degradation and actin rearrangement, initiating a catastrophic collapse of the entire podocyte-stabilizing system. Conclusions: Over expression of miR-206 promotes podocyte injury via downregulation of WT1, which provides a new pathogenic mechanism for FSGS and miR-206 may be a potential therapeutic target.

Histological study on the protective effect of endogenous stem-cell mobilization in Adriamycin-induced chronic nephropathy in rats

Chronic kidney disease is a global health problem with increasing morbidity and mortality. Therefore, this study was planned to test the protective effect of hematopoietic-stem-cell mobilization by granulocyte colony-stimulating factor (G-CSF) on Adriamycin (ADR)-induced chronic renal disease in rats. Thirty albino rats were equally divided into three groups: control, ADR group [rats received a single intravenous injection of ADR (5mg/kg)], and G-CSF group [rats received ADR by the same route and the same dose as the previous group, and then G-CSF (70μg/kg/d) 2 hours after ADR injection then daily for five consecutive days]. At the time of sacrifice (after 6 weeks), blood samples were taken to estimate the blood urea nitrogen and serum creatinine. Kidney sections were stained with hematoxylin and eosin, toluidine blue, Masson's trichrome, periodic acid–Schiff stains, and immunohistochemical staining against CD34 and caspase-3. The G-CSF group exhibited protection against renal injury manifested by reducing blood urea nitrogen and serum-creatinine levels, improving histological architecture, and increasing the proliferative capacity of renal tubules.

Balance between the two kinin receptors in the progression of experimental focal and segmental glomerulosclerosis in mice.

Focal and segmental glomerulosclerosis (FSGS) is one of the most important renal diseases related to end-stage renal failure. Bradykinin has been implicated in the pathogenesis of renal inflammation, whereas the role of its receptor 2 (B2RBK; also known as BDKRB2) in FSGS has not been studied. FSGS was induced in wild-type and B2RBK-knockout mice by a single intravenous injection of Adriamycin (ADM). In order to further modulate the kinin receptors, the animals were also treated with the B2RBK antagonist HOE-140 and the B1RBK antagonist DALBK. Here, we show that the blockage of B2RBK with HOE-140 protects mice from the development of FSGS, including podocyte foot process effacement and the re-establishment of slit-diaphragm-related proteins. However, B2RBK-knockout mice were not protected from FSGS. These opposite results were due to B1RBK expression. B1RBK was upregulated after the injection of ADM and this upregulation was exacerbated in B2RBK-knockout animals. Furthermore, treatment with HOE-140 downregulated the B1RBK receptor. The blockage of B1RBK in B2RBK-knockout animals promoted FSGS regression, with a less-inflammatory phenotype. These results indicate a deleterious role of both kinin receptors in an FSGS model and suggest a possible cross-talk between them in the progression of disease.

Effects of 22-Oxa-Calcitriol on Podocyte Injury in Adriamycin-Induced Nephrosis

Background: In various animal studies, vitamin D has been shown to have a significant effect on reduction of proteinuria and the progression of kidney disease. However, little is known on its renoprotective effect in adriamycin (ADR)-induced nephrosis mice. The present study was intended to determine the therapeutic benefit of 22-oxa-calcitriol (OCT), a vitamin D analog, in reducing proteinuria and its renoprotective effect, i.e. preventing podocyte injury on ADR-induced nephrosis mice. Methods: Three experimental groups were used as follows: (1) nephrosis mice, established by a single intravenous injection of ADR; (2) ADR+OCT mice, nephrosis mice treated with OCT, and (3) mice treated only with OCT as the control group. Podocyte injury was assessed by podocyte apoptosis using the TUNEL assay, podocyte counting, podocyte-specific expressed protein by immunofluorescence and Western blot analysis, and foot process effacement using electron microscopy. Results: Lower proteinuria was observed in ADR+OCT mice. Improvement in glomerulosclerosis and interstitial fibrosis, and prevention of glomerular hyperfiltration were observed in ADR+OCT mice. Immunofluorescence and Western blot analyses showed restoration of downregulated expression of nephrin, CD2AP and podocin. Nevertheless, dendrin expression was not restored. An insignificant reduction in podocyte numbers was found in ADR+OCT mice. Complete foot process effacement was partially prevented in ADR+OCT mice. Conclusions: The results indicate that OCT reduces podocyte injury and has renoprotective effects in ADR nephrosis mice.

Bradykinin receptor 1 activation exacerbates experimental focal and segmental glomerulosclerosis

Focal and segmental glomerulosclerosis (FSGS) is one of the most important causes of end-stage renal failure. The bradykinin B1 receptor has been associated with tissue inflammation and renal fibrosis. To test for a role of the bradykinin B1 receptor in podocyte injury, we pharmacologically modulated its activity at different time points in an adriamycin-induced mouse model of FSGS. Estimated albuminuria and urinary protein to creatinine ratios correlated with podocytopathy. Adriamycin injection led to loss of body weight, proteinuria, and upregulation of B1 receptor mRNA. Early treatment with a B1 antagonist reduced albuminuria and glomerulosclerosis, and inhibited the adriamycin-induced downregulation of podocin, nephrin, and α-actinin-4 expression. Moreover, delayed treatment with antagonist also induced podocyte protection. Conversely, a B1 agonist aggravated renal dysfunction and even further suppressed the levels of podocyte-related molecules. Thus, we propose that kinin has a crucial role in the pathogenesis of FSGS operating through bradykinin B1 receptor signaling.

The protective effect of probucol on adriamycin nephrosis in the rat.

Recent research has indicated the role of reactive oxygen species (ROS) in experimental nephritis. We examined the role of ROS and the effect of probucol, an anti-hyperlipidemic drug with antioxidant activity, on adriamycin (ADR)-induced nephrosis in the rat. Fourteen days after single intravenous injection of ADR (7.5 mg/kg b.w.), a nephrotic state was observed. Compared with the normal control values, the total kidney glutathione content was lower on day 5, but significantly higher on day 14 in the ADR-injected rats. Feeding ADR-injected rats with food containing 1% probucol was effective in reducing urinary protein excretion. Serum lipid peroxide level and kidney total glutathione content, both of which increased on day 14 in the ADR-injected rats, were also decreased significantly by concomitant probucol treatment. During long-term observation period of 18 weeks, probucol treatment relieved both urinary protein excretion and the progression of renal impairment. These protective effects of probucol suggest a role of ROS in the induction and progression of ADR nephrosis.

Rapamycin Attenuates the Severity of Murine Adriamycin Nephropathy

Background: Rapamycin is an immunosuppressive drug with potent antifibrotic activity. We evaluated the effect of rapamycin on murine adriamycin nephropathy, a model of progressive glomerulosclerosis and tubulointerstitial fibrosis. Methods: Adriamycin nephropathy was induced in Balb/c mice by a single intravenous injection of adriamycin. The mice were treated orally with either saline or rapamycin, beginning at the time of adriamycin injection or rapamycin starting 1 week after adriamycin injection. The mice were sacrificed 6 weeks after adriamycin injection. Results: Saline-treated mice developed massive proteinuria and impaired renal function. Kidney sections from saline-treated mice showed marked focal segmental glomerulosclerosis, tubular dilation with protein cast deposition, interstitial fibrosis, and numerous infiltrating macrophages and T lymphocytes. The intrarenal expression of Collagen I and RANTES was also increased. In contrast, both groups of rapamycin-treated mice had markedly reduced proteinuria and preserved renal function, with only mild histological abnormalities. The intrarenal expression of Collagen I and RANTES was reduced, concomitant with a significant reduction in interstitial inflammatory cell infiltration. Conclusions: Rapamycin is effective in attenuating the glomerular and tubulointerstitial abnormalities in adriamycin nephropathy_.The beneficial effects of rapamycin are mediated, at least in part, through reduced RANTES expression and inflammatory cell infiltration.

Inhibition of JAK/STAT Signaling Ameliorates Mice Experimental Nephrotic Syndrome

Background/Aims: This study investigated the role of JAK/STAT, an important pathway for cytokine signal transduction, in the progression of chronic glomerular diseases. Methods: BALB/c mice received a single intravenous injection of adriamycin (10 mg/kg) were sacrificed 2, 4 and 6 weeks later. In the second study, treatment with the selective JAK2 inhibitor AG490 (15 mg/kg, q.d., i.p.) or vehicle was started 5 days after adriamycin injection. Functional and pathologic markers, inflammatory infiltration, expression of pro-inflammatory cytokines and phosphorylation of JAK2/STATs were assessed. Results: JAK/STAT signaling was activated in adriamycin nephropathy. Phosphorylation of JAK2, STAT1 and STAT3 was significantly inhibited by AG490 (p <0.01). Compared to the vehicle-treated controls, AG490 treatment did not reduce proteinuria 2 weeks after induction of the disease, but resulted in significant decrease in proteinuria and serum creatinine at week 6 (p <0.05). Glomerulosclerosis, tubulointerstitial lesions and renal α-SMA expression were also significantly suppressed by AG490 treatment at week 6 (p < 0.01). In addition, AG490 inhibited the expression of MCP-1 mRNA, accompanied by reduced interstitial infiltration of macrophages and T cells (p <0.05). Conclusions: This study suggests that activation of JAK/STAT signaling is involved in the progression of glomerular diseases with proteinuric state.

Inhibition of p38 Mitogen-Activated Protein Kinase and Transforming Growth Factor-β1/Smad Signaling Pathways Modulates the Development of Fibrosis in Adriamycin-Induced Nephropathy

Inflammation and fibrogenesis are the two determinants of the progression of renal fibrosis, the common pathway leading to end-stage renal disease. The p38 mitogen-activated protein kinase (MAPK) and transforming growth factor (TGF)-beta1/Smad signaling pathways play critical roles in inflammation and fibrogenesis, respectively. The present study examined the beneficial renoprotective effect of combination therapy using the p38 MAPK pathway inhibitor (SB203580) and a TGF-beta receptor I (ALK5) inhibitor (ALK5I) in a mouse model of adriamycin (ADR) nephrosis. The p38 MAPK and TGF-beta1/Smad2 signaling pathways were activated in ADR-induced nephropathy in a sequential time course manner. Two weeks after ADR injection, the combined administration of SB203580 (1 mg/kg/24 hours) and ALK5I (1 mg/kg/24 hours) markedly reduced p38 MAPK and Smad2 activities. Moreover, the co-administration of SB203580 and ALK5I to ADR-injected mice resulted in a down-regulation of total and active TGF-beta1 production, reduced myofibroblast accumulation, and decreased expression of collagen type IV and fibronectin. In these mice, retardation in the development of glomerulosclerosis and interstitial fibrosis was observed. In conclusion, although p38 MAPK and TGF-beta1/Smad signaling pathways are distinct they coordinate the progression of renal fibrosis in ADR nephrosis. The co-administration of a p38 MAPK inhibitor and an ALK5 inhibitor may have potential applications in the treatment of renal fibrosis.

A protective role for programmed death 1 in progression of murine adriamycin nephropathy

Programmed death 1 (PD-1) is a novel member of the CD28/cytotoxic T-lymphocyte-associated protein-4 superfamily, which plays an important role in the regulation of activated T cells. However, it is not clear how PD-1 is expressed in normal and diseased kidney, nor if it has a role in progression of chronic renal disease. PD-1 expression and the effect of monoclonal anti-PD-1 antibody (Ab) were examined in murine adriamycin nephropathy (AN). BALB/c mice were divided into three groups: (a) normal mice, (b) adriamycin (ADR) with control immunoglobulin (Ig)G (ADR-IgG), and (c) ADR with anti-PD-1 Ab (ADR-Ab). AN was induced by a single intravenous injection of ADR. Anti-PD-1 Ab was given by intraperitoneal injection on alternate days from day 0 to day 10, or to day 18. Animals were killed at week 4. Renal function, histological change, and cytokine expression were examined. PD-1 mRNA was detected in kidney tissue of mice with AN in a dose- and time-dependent manner. PD-1 was mainly expressed on injured tubule cells and some interstitial cells, which co-stained with alpha-smooth muscle actin in AN, but not in normal kidney. Anti-PD-1 treatment up to day 18, but not to day 10, worsened glomerular and tubulointerstitial injury. The ratio of urinary protein/creatinine was significantly higher in ADR-Ab mice than ADR-IgG mice. The number of macrophages was significantly increased in ADR-Ab mice compared with ADR-IgG mice. Blockade of PD-1 worsened progressive renal histopathological and functional injury in murine AN. This suggests a possible protective role for PD-1 in chronic renal disease, and its potential as a treatment to slow disease progression.

Influence of a low-molecular-weight heparin derivative on the nitric oxide levels and apoptotic DNA damage in adriamycin-induced cardiac and renal toxicity

The spectrum of the anti-apoptotic potential of heparin is currently under scrutiny in various tissues and under various pathological situations. In this study, the role of a low-molecular-weight heparin derivative (LMWH), certoparin in adriamycin-induced oxidative DNA damage has been evaluated in the cardiac and renal tissues. Two groups of male albino rats of the Wistar strain (140 ± 10 g) received a single intravenous injection of adriamycin (7.5 mg/kg), and one of them received low-molecular-weight heparin (Certoparin Sodium, 300 μg/day/rat s.c.) treatment, commencing on day 8, continued for a week. The nitrosative stress in ADR cytotoxicity is indicated by the 1.51-fold cardiac and 2.36-fold renal increase in reactive nitrogen species (RNS), while LMWH treatment restores normalcy ( p < 0.001). The influence of LMWH on the pro-inflammatory and pro-apoptotic cytokine, TNF-α was studied. Renal and cardiac levels of TNF-α showed a significant rise ( p < 0.001) in the ADR cytotoxic group, while the TNF-α values departed towards control levels in the LMWH treated group ( p < 0.001). DNA damage indicated by the fragmentation pattern (agarose gel electrophoresis) and the significantly increased comet tail length ( p < 0.001) observed after alkaline single cell gel electrophoresis confirmed the toxicity induced by ADR on DNA in the untreated group. In the LMWH-treated group, the observation of intact DNA band after agarose gel electrophoresis, and the finding of comet tail length being comparable with that of the control substantiated the protection rendered by the LMWH, certoparin. In short, the results suggest that the low-molecular-weight heparin derivative, certoparin exerts beneficial effects on the nitrosative status, and on the biological macromolecules as DNA and curtails the rise of the pro-apoptotic and pro-inflammatory cytokine, TNF-α in the cardiac and renal tissues.

Beneficial cardio-renovascular effects of a low-molecular-weight heparin-derivative on adriamycin-induced glycosaminoglycanuria and tissue lipid abnormalities

The present work includes a study on the glycosaminoglycanuric condition induced by adriamycin (ADR, a chemotherapeutic agent) and the accompanying secondary hyperlipidemia, wherein the treatment with a low-molecular-weight heparin-derivative (LMWH), certoparin, is evaluated for its protective role (if any) on these parameters. Two groups of male albino rats of the Wistar strain (140 ± 10 g) received a single intravenous injection of adriamycin (7.5 mg/kg), and one of these groups was treated with a low-molecular-weight heparin-derivative (Certoparin Sodium, Troparin ®; 300 μg/day/rat s.c.), commencing on day 8, for a week. Urinary total glycosaminoglycans excretion of the untreated ADR-induced group was found to increase on the 8th and the 15th days of observation, when compared with the controls. The LMWH treatment commencing on day 8 resulted in minimising the glycosaminoglycans (GAGs) excretion by day 15 ( p < 0.001). Plasma, cardiac, hepatic and renal lipids (cholesterol, triglycerides and phospholipids) showed a sharp increase in the pathologic group, along with a rise in plasma LDL and VLDL cholesterol and drop in HDL cholesterol levels, paralleled by abnormal activities of the enzymes involved in lipid metabolism. LMWH treated group showed a normalised lipid profile and the activities of the lipid-metabolising enzymes was close to that of controls. It is concluded herein that adriamycin administration resulted in severe nephropathy manifested by increased glycosaminoglycanuria and abnormal lipid metabolism, and that LMWH treatment afforded substantial protection by restoring glomerular structure and function, and normalised the plasma and tissue lipid levels, lipoprotein profile and the activities of lipid-metabolising enzymes.

The cytoprotective role of a low-molecular-weight heparin fragment studied in an experimental model of glomerulotoxicity

Abnormal glomerular glycosaminoglycan metabolism is involved in the onset of the morphological and functional aberrations of glomerulopathies. In the present study, a heparin derivative, low-molecular-weight heparin, was tested for its ability to afford renoprotection in an established model of experimental glomerulopathy. Two groups of male albino rats of the Wistar strain (140±10 g) received a single intravenous injection of adriamycin (7.5 mg/kg) to induce glomerulopathy, and one of them received low-molecular-weight heparin (Certoparin Sodium, Troparin®; 300 μg/day/rat s.c.) treatment, commencing on day 8, for a week. Urinary protein/creatinine ratio, serum albumin, urea, uric acid and creatinine clearance were evaluated. Renal cell injury was assessed in terms of renal tissue lactate dehydrogenase, aminotransferases (aspartate and alanine transaminases) and alkaline phosphatase activities, as well as renal antioxidant status (superoxide dismutase, catalase and glutathione peroxidase, reduced glutathione, vitamins E and C). The kidney tissue was subjected to histopathologic examination. Low-molecular-weight heparin significantly reduced proteinuria and improved creatinine clearance and serum albumin levels in the rats with glomerulopathy. The significant rise in serum uric acid in the rats with glomerulopathy was reversed by low-molecular-weight heparin. Altered tissue enzyme activities in response to injury, oxidative stress challenged renal antioxidant system and abnormal renal histology were observed in the untreated nephrotic rats, while low-molecular-weight heparin treatment protected the nephrotic rats against these changes. Thus, in this study, low-molecular-weight heparin was evaluated for its role in combating glomerular injury, on the basis of some salient biochemical parameters, oxidative injury indices and histologic picture. The ability of low-molecular-weight heparin to restore glomerular anatamo-functional features in this nephrotoxic condition illuminates its multi-faceted renoprotective role.

Favourable influence of low molecular weight heparin in mitigating the peroxidative membrane damage induced by a cytotoxic agent and an atherogenic diet.

The present study is aimed to demonstrate the protective effect of a heparin derivative, low molecular weight heparin (LMWH) against erythrocyte membrane injury. Two models serve to induce membrane lipid peroxidative damage, namely a potent cytotoxic agent, adriamycin and a hypercholesterolemic atherogenic diet. Two groups of male Wistar rats (140 +/- 10 g) received a single intravenous injection of adriamycin (ADR, 7.5 mg/kg), while two other groups were fed an atherogenic diet comprising a supplementation of 4% cholesterol, 1% cholic acid and 0.5% thiouracil (CCT diet) for 2 weeks. For each of the above two groups, LMWH (Troparin; 300 microg/day per rat subcutaneously) treatment commenced on day 8 and continued for a week. One group was maintained as the normal control group, and another group that received only LMWH treatment was designated as the LMWH drug control group. Erythrocyte membrane was isolated and assayed for its cholesterol levels, lipid peroxidation and ATPases activity. The activities of antioxidant enzymes were assessed in the haemolysate. The findings of the study were that both adriamycin and the atherogenic diet produced elevated membrane cholesterol levels and lipid peroxidation. The membrane ATPases suffered loss in activity. Accentuated oxidative stress was marked by rise in the activities of antioxidant enzymes (SOD, catalase and GPx). LMWH intervention reverted these changes thereby normalizing the membrane composition and function. The membrane protective effect of LMWH is illuminated by this work.

Experimental study on effect of bushen huoxue xiezhuo decoction in treating minute lesion nephropathy

To explore the therapeutic effect and mechanism of Bushen Huoxue Xiezhuo Decoction (BHXD) in treating minimal change nephropathy (MCN) in rats. The MCN model rats established by a single intravenous injection of Adriamycin were divided into the model, BHXD group, and a normal group was set up for control. The effect of treatment on renal function, hemorrheologic parameters, renal tissue TGF-beta 1 expression and polyanion sites on glomerular basement membrane were observed dynamically. After treatment, all the parameters between the BHXD group and the model group were significantly different respectively, morphological observation also showed the pathological changes in the BHXD group were milder than those in the model group. BHXD treatment could markedly improve the renal function, alleviate blood hypercoagulability and hyperviscosity, protect the anion barrier and delay the progression of glomerular fibrosis and sclerosis.

Depletion of CD4+ T cells aggravates glomerular and interstitial injury in murine adriamycin nephropathy

CD4(+) T cells play an important role in various types of immunologic renal disease, including lupus nephritis, IgA nephropathy, and crescentic glomerulonephritis. CD4(+) T cells are also major infiltrating lymphocytes in chronic tubulointerstitial inflammation associated with nonimmunological renal diseases. We suspected that CD4(+) T cells might contribute to disease progression and loss of renal function in chronic proteinuric renal disease (CPRD). To investigate this possibility, the effect of monoclonal antibody against CD4(+) lymphocytes (anti-CD4) was studied in a murine model (adriamycin nephropathy) of CPRD. Adriamycin nephropathy was produced in male BALB/c mice by a single intravenous injection of adriamycin (11 mg/kg). Anti-CD4 was given by intraperitoneal injection following the development of proteinuria at days 5, 6, 7, 21, and 37 after adriamycin. After six weeks, renal function and histology were studied by histomorphometry, immunohistochemistry, and flow cytometry. Flow cytometric analysis showed a marked decrease in the number of CD4(+) T cells in blood and spleen of the antibody-treated animals (N = 7, P < 0.01). Adriamycin plus CD4(+) depletion mice had significantly greater mesangial expansion, glomerular sclerosis, and interstitial expansion than the mice on adriamycin alone. Interstitial infiltration with macrophages and CD8(+) cells was significantly increased in adriamycin plus CD4(+) depletion mice. Creatinine clearance (17.5 +/- 0.54 vs. 29.2 +/- 0.89 microL/min, P < 0.001) was significantly worse in the adriamycin plus CD4(+) depletion mice than in adriamycin alone mice and correlated with histologic change in glomeruli and interstitium. Depletion of CD4(+) T cells promotes glomerular and interstitial injury in mice with established adriamycin nephropathy. These findings suggest that CD4(+) T cells have a protective role against the progression of adriamycin nephropathy.

The influence of cyclosporin on lipid peroxidation and superoxide dismutase in adriamycin nephropathy in rats.

Cyclosporin A (CsA) was shown to reduce proteinuria in nephrotic syndrome, but its potential to increase lipid peroxidation may play a role in cyclosporin nephrotoxicity. The influence of cyclosporin treatment on the lipid peroxidation (assessed as malondialdehyde (MDA) in plasma and kidney homogenates using HPLC and reaction with thiobarbituric acid) and the activity of superoxide dismutase (SOD) in erythrocytes was studied in rats with nephrotic syndrome induced by single intravenous injection of adriamycin. Rats with nephrotic syndrome treated from the beginning with cyclosporin had lower proteinuria than untreated nephrotic rats. Free MDA in blood and kidney homogenates was significantly elevated in untreated nephrotic rats in comparison with controls. Activity of SOD in erythrocytes was significantly elevated in nephrotic rats treated with cyclosporin (113.40 +/- 34.31 mU/10(6) erythrocytes) in comparison with the control group (55.63 +/- 9.90 mU/10(6) erythrocytes, p < 0.001), rats treated with cyclosporin (65.7 +/- 17.49 mU/10(6) erythrocytes, p < 0.01) and untreated nephrotic rats (65.07 +/- 17.49 mU/10(6) erythrocytes, p < 0.001). In conclusion, cyclosporin reduced proteinuria in rats with mild adriamycin nephropathy (similar to human minimal change disease). Cyclosporin also partially counteracted adriamycin-induced lipid peroxidation probably due to the stimulation of antioxidant enzyme SOD. The possible contribution of decreased lipid peroxidation to the antiproteinuric effect of cyclosporin deserves further study.

Antiproteinuric effect of ciclosporin A in adriamycin nephropathy in rats.

Ciclosporin A (CsA) can reduce proteinuria in various forms of human and experimental glomerulopathies. This antiproteinuric effect can be the result of a decrease of immunological damage, a decrease in the glomerular filtration rate (GFR), or a change in the permselective properties of the glomerular capillary wall. In this study we investigated the effect of CsA on Adriamycin-induced nephropathy in rats. A single intravenous injection of Adriamycin (5 mg/kg body weight) induced a severe nephrotic syndrome with a massive albuminuria (+/- 400 mg/24 h from 3 weeks onwards) and a hypoalbuminemia (+/- 7 mg/ml after 5 weeks). The IgG/albumin selectivity index was 0.16 +/- 0.05, indicating a preferential loss of albumin. A 5-day treatment with CsA reduced the albumin excretion by almost 50% (from 336 +/- 91 to 178 +/- 58 mg/24 h; p = 0.002) and induced an increase in the serum albumin level (from 7.1 +/- 4.1 to 12.8 +/- 3.2 mg/ml; p = 0.002) in contrast to the vehicle olive oil (OO). CsA also decreased the GFR by 40% (from 0.74 +/- 0.11 to 0.41 +/- 0.11 mg/ml/100 g body weight; p = 0.002). Albuminuria corrected for the GFR (fractional excretion of albumin, FE(alb)) was still significantly lower in CsA-treated than in OO-treated animals (FE(alb) CsA: 1.35 +/- 0.88, FE(alb) OO: 3.17 +/- 2.29%; p = 0.0005). This suggests that other factors are also involved in the reduction of albuminuria. To exclude that CsA has an effect on the tubular reabsorption of albumin, we evaluated the blockade of the tubular reabsorption by lysine and found no difference in albuminuria between the CsA- and OO-treated groups. These experiments suggest that the antiproteinuric effect of CsA is not (only) due to a decrease in the GFR, but also to a decrease of the enhanced permeability of the glomerular capillary wall for albumin.

Suppressive effect of superoxide dismutase on adriamycin nephropathy.

A single intravenous injection of adriamycin (ADR) results in marked proteinuria and glomerular morphological changes that are similar to minimal-change disease in humans. We examined the effect of superoxide dismutase (SOD) on ADR-induced proteinuria. ADR in a dose of 7.5 mg/kg body weight significantly increased urinary protein by day 14; proteinuria rapidly increased thereafter. Concurrent administration of SOD (50 mg/kg) over 30 min prior to and 30 min following ADR injection markedly reduced proteinuria. Twenty-one days after the treatment with SOD, the amount of urinary protein was 108.6 +/- 43.1 mg/24 h in the experimental animals, while it was 221.6 +/- 102.9 mg/24 h in the ADR control group (p less than 0.05). There were also less severe glomerular morphologic changes in the SOD group versus ADR controls. The protective effects of SOD provide indirect evidence that oxygen free radicals are important mediators of ADR-induced proteinuria.