Histopathological Examination Of Kidney Tissues Research Articles

Nephrotoxicity of cefepime: A new cephalosporin antibiotic in rats

Objectives:To investigate the nephrotoxic effect and biochemical alterations induced by cefepime in rats.Materials and Methods:Cefepime was administered intramuscularly at doses of 45, 90 and 180 mg/kg b.wt. once daily for 5 consecutive days. The serum and urine samples were used for quantitative determination of urea, creatinine, glucose, total protein, calcium, sodium and potassium. The histopathological examination of kidney tissues was performed 1, 4 and 8 days after the last dose of cefepime administration.Results:Cefepime induced a significant increase in the total amount of urine per day, urea and creatinine concentration in the serum and urine and significant decrease in their clearance. Cefepime also caused a significant gluocosuria and proteinuria and significant decrease in their serum concentrations. The effect of cefepime on serum and urine concentrations of calcium, sodium and potassium were also determined. Cefepime injection in the three tested doses caused renal tubular, glomerular and vascular changes. The severity of these changes was dose dependent. In conclusion, these results suggest a possible contribution of cefepime in the nephrotoxicity and biochemical alterations, especially at high doses. Therefore, the renal functions should be monitored during the cefepime therapy.

Effect of atorvastatin and erythropoietin on renal fibrosis induced by partial unilateral ureteral obstruction in rats

ObjectiveThis work aims at investigating the effects of atorvastatin and erythropoietin (EPO) on tubulointerstitial fibrosis induced by partial unilateral ureteral obstruction (PUUO) in rats.BackgroundRenal fibrosis is the final manifestation of chronic kidney disease. It is one of the biggest problems in nephrology, indicating that patients inevitably reach end-stage renal disease. Atorvastatin has anti-inflammatory, antiproliferative, and immunomodulatory potential. EPO has been demonstrated to play an important cytoprotective role.MethodsFifty adult albino rats were divided into five equal groups: group 1 received saline intraperitoneally and methylcellulose orally for 14 days and served as the negative control; group 2 (sham-operated group) rats underwent the same surgical procedures as group 3 without ureteral obstruction; group 3 rats underwent PUUO without any medication; group 4 rats underwent PUUO and received atorvastatin at a dose of 50 mg/kg orally; group 5 rats underwent PUUO and received EPO at a dose of 3.000 IU/kg daily intraperitoneally. After 14 days, systolic blood pressure was measured. Blood and urine samples were also collected for measurement of serum transforming growth factor-β1, tumor necrosis factor-͍, urea and creatinine, and urinary protein and albumin levels. Renal tissue samples were collected for determination of malondialdehyde and ͍-smooth muscle actin levels, as well as for histopathological and immuonohistochemical examination.ResultsOur results showed that systolic blood pressure; serum levels of transforming growth factor-β1, tumor necrosis factor-α, and malondialdehyde; and biochemical parameters were significantly elevated. Histopathological examination of kidney tissue revealed marked degenerative changes and increased expression of α-smooth muscle actin in group 3 compared with groups 1 and 2. In contrast, biochemical, histological, and immuonohistochemical features in groups 4 and 5 showed significant improvement compared with group 3.ConclusionIt is concluded that both atorvastatin and EPO have renoprotective effects against renal fibrosis, shown by improvement in kidney functions and using fibrosis markers.

Pyridoxamine, an inhibitor of protein glycation, in relation to microalbuminuria and proinflammatory cytokines in experimental diabetic nephropathy

Diabetic nephropathy (DN) is one of the major complications that develop as consequence of chronic and uncontrolled hyperglycaemia. Hyperglycaemia initiates various processes, one of which is protein glycation, leading to the formation of advanced glycation end products. Alteration of intracellular signalling, gene expression, release of proinflammatory molecules and free radicals are examples of such changes and they contribute to the initiation of diabetic complications. In the current manuscript, we studied the effect of pyridoxamine (PM) on protein glycation, oxidative stress, interleukin-1α (IL-1α), IL-6, C-reactive protein (CRP), gene expression of tumour necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1) in relation to microalbuminuria and kidney functions in a model of alloxan-induced diabetic rats. We have observed that onset of microalbuminuria has preceded the gradual increase of blood sugar level in diabetic rats. In diabetic rats, gene expression of TNF-α and TGF-β1 recorded a gradual increase and marked increase was observed after one and two weeks of alloxan administration, in comparison with normal rats. PM induced significant decrease in kidney malondialdehyde content and the gene expression of TNF-α and TGF-β1, in addition to levels of serum glucose, fructosamine, urea, creatinine, IL-1α, IL-6, CRP and urine microalbumin. Histopathological examination of kidney tissues showed certain improvements as compared with diabetic control. In conclusion, our results may provide a supporting evidence for the therapeutic benefit of PM in DN.

How Does Colistin-Induced Nephropathy Develop and Can It Be Treated?

Colistin is an old antibiotic used in the treatment of Gram-negative infections. It was once suspended because of its nephrotoxic effect but has since been reintroduced due to multidrug-resistant bacterial infections. The pathogenesis of colistin-associated nephropathy has not been clarified, and there is currently no effective therapeutic or prophylactic agent available. The aim of this study was to investigate the roles of caspase-associated apoptosis and caspase 1, calpain 1, inducible nitric oxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS) expression in the pathogenesis of colistin-associated nephrotoxicity and the effect of grape seed proanthocyanidin extract (GSPE) in preventing it. Twenty-four rats were divided into three groups: control, colistin, and colistin plus GSPE (colistin+GSPE). Colistin-associated nephropathy was induced by the administration of 300,000 IU/kg of body weight/day colistin intraperitoneally for 7 days. The experiment was discontinued on the seventh day. Blood was collected for measurements of blood urea nitrogen (BUN) and creatinine levels. Histopathological examination of kidney tissue and caspase 1 and 3, iNOS, eNOS, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL), and calpain 1 staining was also performed. Significant increases in BUN levels; creatinine levels; renal histopathological scores; and TUNEL, caspase 1 and 3, calpain 1, iNOS, and eNOS staining were observed for the colistin group compared to the control group. Significant decreases in BUN levels; creatinine levels; renal histopathological scores; and TUNEL, caspase 1 and 3, calpain 1, iNOS, and eNOS staining were observed in the colistin+GSPE group compared to the colistin group. Our study shows, for the first time in the literature, that caspase-mediated apoptosis, iNOS, caspase 1, and calpain 1 are involved in the pathogenesis of colistin-associated nephropathy. GSPE had a renoprotective effect, as shown by the lowered levels of these mediators.

Effect of Nigella sativa on the kidney function in rats.

Nigella sativa (N. sativa) is an amazing herb which is used in traditional medicine for a wide range of illnesses including bronchial asthma, dysentery, gastrointestinal problems, as well as beneficial effect on blood lipids, lowering blood pressure, serum cholesterol, and triglycerides level. This study aimed to determine the toxic effect of N. sativa powder on the kidney function which was evaluated by serum urea and creatinine and through histopathological examination of kidney tissue. In this study, 24 male Sprague Dawley rats were randomly divided into four groups (six each). The rats were kept in the separate cage with three rats per cage. The treatment groups were given rat pellet containing N. sativa dose at 0.01, 0.10, and 1.00 g/kg body weight which were considered as low, normal, and high dose for five weeks while control group fed with rat chow pellet without supplementation. At the end of 35 days, the rats were sacrificed to take the blood sample and to remove the kidney organ for toxicity evaluation. Statistical analyses were done through one-way ANOVA using SPSS. The finding revealed that there was no significant difference in serum urea of treatment groups compared with the control group. The results showed a significant decline in serum creatinine of high dose of Nigella sativa treated compared with low dose treated and control groups (p<0.05). Histopathological examination of kidney tissue showed normal kidney architecture with no tissue degeneration, inflammation, necrosis, and tubular dilation in all groups. With the evidence of normal urea and creatinine level in blood and normal kidney tissue in histology examination for all treatment groups, it is suggested that there is no toxic effect on kidney function of Nigella sativa at different doses for five-week period.

Role of quercetin and arginine in ameliorating nano zinc oxide-induced nephrotoxicity in rats.

BackgroundNanoparticles are small-scale substances (<100 nm) with unique properties. Therefore, nanoparticles pose complex health risk implications. The objective of this study was to detect whether treatment with quercetin (Qur) and/or arginine (Arg) ameliorated nephrotoxicity induced by two different doses of nano zinc oxide (n-ZnO) particles.MethodZnO nanoparticles were administered orally in two doses (either 600 mg or 1 g/Kg body weight/day for 5 conscutive days) to Wister albino rats. In order to detect the protective effects of the studied antioxidants against n-ZnO induced nepherotoxicity, different biochemical parameters were investigated. Moreover, histopathological examination of kidney tissue was performed.ResultsNano zinc oxide-induced nephrotoxicity was confirmed by the elevation in serum inflammatory markers including: tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6); and C-reactive protein (CRP). Moreover, immunoglobulin (IGg), vascular endothelium growth factor (VEGF), and nitric oxide (NO) were significantly increased in rat serum. Serum urea and creatinine levels were also significantly increased in rats intoxicated with n-ZnO particles compared with the control group. Additionally, a significant decrease in the non-enzymatic antioxidant reduced glutathione (GSH) was shown in kidney tissues and serum glucose levels were increased. These biochemical findings were supported by a histopathological examination of kidney tissues, which showed that in the animals that received a high dose of n-ZnO, numerous kidney glomeruli underwent atrophy and fragmentation. Moreover, the renal tubules showed epithelial desquamation, degeneration and necrosis. Some renal tubules showed casts in their lumina. Severe congestion was also observed in renal interstitium. These effects were dose dependent. Cotreatment of rats with Qur and/or Arg along with n-ZnO significantly improved most of the deviated tested parameters.ConclusionsThe data show that Qur has a beneficial effect against n-ZnO oxidative stress and related vascular complications. Also, its combination with Arg proved to be even more effective in ameliorating nano zinc oxide nephrotoxicity.

Cyclophosphamide-induced nephrotoxicity, genotoxicity, and damage in kidney genomic DNA of Swiss albino mice: the protective effect of Ellagic acid

Cyclophosphamide (CPM), an alkylating agent is used as an immunosuppressant in rheumatoid arthritis and in the treatment of several cancers as well. In this study, Ellagic acid (EA), a naturally occurring plant polyphenol, was evaluated for its antigenotoxicity and antioxidant efficacy against the CPM-induced renal oxidative stress and genotoxicity in Swiss albino mice. The mice were given a prophylactic treatment of EA orally at a dose of 50 and 100 mg/kg body weight (b wt) for seven consecutive days before the administration of a single intraperitoneal (i.p.) injection of CPM at 50 mg/kg b wt. The modulatory effects of EA on CPM-induced nephrotoxicity and genotoxicity were investigated by assaying oxidative stress biomarkers, serum kidney toxicity markers, DNA fragmentation, alkaline unwinding assay, micronuclei (MN) assay, and by histopathological examination of kidney tissue. A single intraperitoneal administration of CPM in mice increased malondialdehyde level with depletion in glutathione content, antioxidant enzymes activities, viz. glutathione peroxidase, glutathione reductase, catalase, quinone reductase, induced DNA strand breaks, and MN induction. EA oral administration at both doses caused significant reduction in their levels, restoration in the activities of antioxidant enzymes, reduction in MN formation, and DNA fragmentation. Serum toxicity marker enzymes like BUN, creatinine, and LDH were also increased after CPM treatment which was significantly decreased in EA pretreated groups. Present findings suggest a prominent role of EA against CPM-induced renal injury, DNA damage, and genotoxicity.

Protective Effects of the Angiotensin II Receptor Blocker Losartan on Cisplatin-Induced Kidney Injury

Background: In the present study, we investigated the possible modulatory effect of losartan, an angiotensin receptor blocker, on oxidative stress induced by cisplatin (CDDP) as well as on CDDP uptake by the kidney. Methods: Rats were injected with a single dose of CDDP (7 mg/kg) and/or losartan (in either a single dose of 60 mg/kg or divided doses (10 mg/kg daily for 6 days), starting 1 h before CDDP injection. In addition, rat renal cortical slices were incubated with CDDP (2 mM) and/or losartan (2 mM) for 4 h. Nephrotoxicity was evaluated by measuring serum creatinine and blood urea nitrogen (BUN) in vivo and lactate dehydrogenase (LDH) leakage in vitro; histopathological examination of kidney tissue was also done. Oxidative stress markers including reduced glutathione (GSH) and lipid peroxides were also assessed. Furthermore, CDDP uptake by renal cortical slices was determined. Results: Losartan has protective effects against CDDP-induced nephrotoxicity as evidenced by restoration of normal serum levels of creatinine and BUN, and LDH leakage. Histopathological examination of the kidney confirmed these results. Also, losartan significantly counteracted CDDP-induced lipid peroxidation and GSH depletion. However, losartan did not affect CDDP uptake by the kidney. Conclusion: Our results indicate that losartan has proved to be a promising drug for clinical use as a nephroprotectant against CDDP-induced nephrotoxicity.

Increased urinary losses of carnitine and decreased intramitochondrial coenzyme A in gentamicin-induced acute renal failure in rats

This study examined whether carnitine deficiency is a risk factor and should be viewed as a mechanism during the development of gentamicin (GM)-induced ARF as well as exploring if carnitine supplementation could offer protection against this toxicity. Adult male Wistar albino rats were assigned to one of six treatment groups: group 1 (control) rats were given daily intraperitoneal (I.P.) injections of normal saline for 8 consecutive days; groups 2, 3 and 4 rats were given GM (80 mg/kg/day, I.P.), l-carnitine (200 mg/kg/day, I.P.) and d-carnitine (250 mg/kg/day, I.P.), respectively, for 8 consecutive days. Rats of group 5 (GM plus d-carnitine) received a daily I.P. injection of d-carnitine (250 mg/kg/day) 1 h before GM (80 mg/kg/day) for 8 consecutive days. Rats of group 6 (GM plus l-carnitine) received a daily I.P. injection of l-carnitine (200 mg/kg/day) 1 h before GM (80 mg/kg/day) for 8 consecutive days. GM significantly increased serum creatinine, blood urea nitrogen (BUN), urinary carnitine excretion, intramitochondrial acetyl-CoA and total nitrate/nitrite (NOx) and thiobarbituric acid reactive substances (TBARS) in kidney tissues and significantly decreased total carnitine, intramitochondrial CoA-SH, ATP, ATP/ADP and reduced glutathione (GSH) in kidney tissues. In carnitine-depleted rats, GM caused a progressive increase in serum creatinine, BUN and urinary carnitine excretion and a progressive decrease in total carnitine, intamitochondrial CoA-SH and ATP. Interestingly, l-carnitine supplementation resulted in a complete reversal of the increase in serum creatinine, BUN, urinary carnitine excretion and the decrease in total carnitine, intramitochondrial CoA-SH and ATP, induced by GM, to the control values. Moreover, the histopathological examination of kidney tissues confirmed the biochemical data, where l-carnitine prevents and d-carnitine aggravates GM-induced ARF. (i) GM-induced nephrotoxicity leads to increased urinary losses of carnitine; (ii) carnitine deficiency is a risk factor and should be viewed as a mechanism during the development of GM-induced ARF; and (iii) carnitine supplementation ameliorates the severity of GM-induced kidney dysfunction by increasing the intramitochondrial CoA-SH/acetyl-CoA ratio and ATP production.

Norcantharidin Ameliorates Proteinuria, Associated Tubulointerstitial Inflammation and Fibrosis in Protein Overload Nephropathy

Norcantharidin (NCTD), the demethylated analog of cantharidin isolated from Mylabris, is an anticancer drug routinely used against various human cancers in China. The aims of this study are to learn if NCTD has a protective action against severe proteinuria and consequent interstitial inflammation and fibrosis, and if the inhibition of nuclear factor-ĸB (NF-ĸB) and connective tissue growth factor (CTGF) by NCTD might be involved. Male Sprague-Dawley rats with protein overload nephropathy induced by intraperitoneally injected bovine serum albumin were used as a model. The histopathological examination of kidney tissue in the 9th week by light microscopy and scanning electron microscopy revealed that inflammatory cells had extensively infiltrated into the tubulointerstitial areas with interstitial fibrosis. The administration of NCTD at 0.1 mg/kg/day to the bovine-serum-albumin-injected animal models effectively reduced the proteinuria, and prevented the proteinuria-induced interstitial inflammation and fibrosis. Expressions of the NF-ĸB p65 subunit and CTGF, detected by immunohistochemistry, Western blotting and reverse-transcription polymerase chain reaction, were upregulated in protein overload nephropathy and were attenuated by NCTD. Inhibition of the expressions of the NF-ĸB p65 subunit and CTGF was one beneficial effect of NCTD. These results suggest that in addition to the antiproteinuric action of NCTD, due to its anti-inflammatory and antifibrotic effects as shown in the present study, it may become a therapeutic agent for proteinuria and its associated chronic inflammatory and fibrotic nephropathy.

REVERSAL OF CISPLATIN‐INDUCED CARNITINE DEFICIENCY AND ENERGY STARVATION BY PROPIONYL‐l‐CARNITINE IN RAT KIDNEY TISSUES

1. The present study examined whether propionyl-L-carnitine (PLC) could prevent the development of cisplatin (CDDP)-induced acute renal failure in rats. 2. Forty adult male Wistar albino rats were divided into four groups. Rats in the first group were injected daily with normal saline (2.5 mL/kg, i.p.) for 10 consecutive days, whereas the second group received PLC (250 mg/kg, i.p.) for 10 consecutive days. Animals in the third group were injected daily with normal saline for 5 consecutive days before and after a single dose of CDDP (7 mg/kg, i.p.). Rats in the fourth group received a combination of PLC (250 mg/kg, i.p.) for 5 consecutive days before and after a single dose of CDDP (7 mg/kg, i.p.). On Day 6 following CDDP treatment, animals were killed and serum and kidneys were isolated for analysis. 3. Injection of CDDP resulted in a significant increase in serum creatinine, blood urea nitrogen (BUN), thiobarbituric acid-reactive substances (TBARS) and total nitrate/nitrite (NO(x)), as well as a significant decrease in reduced glutathione (GSH), total carnitine, ATP and ATP/ADP in kidney tissues. 4. Administration of PLC significantly attenuated the nephrotoxic effects of CDDP, manifested as normalization of the CDDP-induced increase in serum creatinine, BUN, TBARS and NO(x) and the CDDP-induced decrease in total carnitine, GSH, ATP and ATP/ADP in kidney tissues. 5. Histopathological examination of kidney tissues from CDDP-treated rats showed severe nephrotoxicity, in which 50-75% of glomeruli and renal tubules exhibited massive degenerative changes. Interestingly, administration of PLC to CDDP-treated rats resulted in a significant improvement in glomeruli and renal tubules, in which less than 25% of glomeruli and renal tubules exhibited focal necrosis. 6. Data from the present study suggest that PLC prevents the development of CDDP-induced acute renal injury by a mechanism related, at least in part, to the ability of PLC to increase intracellular carnitine content, with a consequent improvement in mitochondrial oxidative phosphorylation and energy production, as well as its ability to decrease oxidative stress. This will open new perspectives for the use of PLC in the treatment of renal diseases associated with or secondary to carnitine deficiency.

THYMOQUINONE SUPPLEMENTATION PREVENTS THE DEVELOPMENT OF GENTAMICIN‐INDUCED ACUTE RENAL TOXICITY IN RATS

1. The present study investigated the possible protective effects of thymoquinone (TQ), a compound derived from Nigella sativa with strong anti-oxidant properties, against gentamicin (GM)-induced nephrotoxicity. 2. A total of 40 adult male Wistar albino rats was divided into four groups. Rats in the first group were injected daily with normal saline (2.5 mL/kg, i.p.) for 8 consecutive days, whereas rats in the second group received TQ (50 mg/L in drinking water) for 8 consecutive days. Animals in the third group were injected daily with GM (80 mg/kg, i.p.) for 8 consecutive days, whereas animals in the fourth group received a combination of GM (80 mg/kg, i.p.) and TQ (50 mg/L in drinking water) for 8 consecutive days. 3. Gentamicin resulted in a significant increase in serum creatinine, blood urea nitrogen (BUN), thiobarbituric acid-reactive substances (TBARS) and total nitrate/nitrite (NOx) and a significant decrease in reduced glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT) and ATP levels in kidney tissues. 4. Interestingly, TQ supplementation resulted in a complete reversal of the GM-induced increase in BUN, creatinine, TBARS and NOx and decrease in GSH, GPx, CAT and ATP to control values. Moreover, histopathological examination of kidney tissues confirmed the biochemical data, wherein TQ supplementation prevents GM-induced degenerative changes in kidney tissues. 5. Data from the present study suggest that TQ supplementation prevents the development of GM-induced acute renal failure by a mechanism related, at least in part, to its ability to decrease oxidative stress and to preserve the activity of the anti-oxidant enzymes, as well as it ability to prevent the energy decline in kidney tissues.

Colchicine vs. Omega-3 Fatty Acids for Prevention of Chronic Cyclosporine Nephrotoxicity in Sprague Dawley Rats: An Experimental Animal Model

In view of the high cost of the new immunosuppressive drugs, which represents a challenge for both patients and governmental resources especially in developing countries, trials to prevent side effects of the first calcineurin inhibitor discovered (cyclosporine, Cs) are of particular interest. In this prospective randomized experimental study, 60 male Sprague Dawley rats were enrolled. Group 1 served as negative control group and received olive oil. Group 2 received Cs orally 100 mg/kg for 80 days and served as positive control group. Group 3 was given daily colchicine (30 microg/kg/day) in addition to Cs. Group 4 was given omega-3 fatty acids (100 mg/kg/day) in addition to Cs. Animals were subjected every other week to laboratory assessment for serum creatinine, sodium, potassium, and Cs whole-blood through levels. At the end point, the animals were sacrificed, and kidney tissue was examined for histopathological changes. There were no significant differences in serum creatinine, creatinine clearance, and serum sodium and potassium in all groups. Histopathological examination of kidney tissues showed focal tubular atrophy and interstitial fibrosis in inner medulla and inner strip of the outer medulla in all Cs-treated animals. Morphological changes were significantly less in colchicine-treated rats compared to omega-3 fatty acid-treated rats and absent in the negative control group. Furthermore, immunostaining showed positive reactions for vimentin in Cs-treated animals only. Colchicine and omega-3 fatty acids are protective for the kidney against cyclosporine-induced nephropathy; however, colchicine is more protective than omega-3 fatty acid.

The haemotoxicity of mitomycin in a repeat dose study in the female CD-1 mouse.

Mitomycin (MMC), like many antineoplastic drugs, induces a predictable, dose-related, bone marrow depression in man and laboratory animals; this change is generally reversible. However, there is evidence that MMC may also cause a late-stage or residual bone marrow injury. The present study in female CD-1 mice investigated the haematological and bone marrow changes induced by MMC in a repeat dose study lasting 50 days. Control and MMC-treated mice were dosed intraperitoneally on eight occasions over 18 days with vehicle, or MMC at 2.5 mg/kg, autopsied (n = 6-12) at 1, 7, 14, 28, 42 and 50 days after the final dose and haematological changes investigated. Femoral nucleated bone marrow cell counts and levels of apoptosis were also evaluated and clonogenic assays carried out; serum levels of FLT3 ligand (FL) were assessed. At day 1 post-dosing, MMC induced significant reductions in RBC, Hb and haematocrit (HCT) values, and there were decreases in reticulocyte, platelet, and femoral nucleated cell counts (FNCC); neutrophil, lymphocyte and monocyte values were also significantly reduced. On days 7 and 14 post-dosing, all haematological parameters showed evidence of a return towards normal values, but at these times, and at day 28, values for RBC and FNCC remained significantly reduced in comparison with controls. At days 42 and 50 post-dosing, many haematological parameters in MMC-treated mice had returned to control levels; however, there remained evidence of late-stage effects on RBC, Hb and HCT values, and FNCC also continued to be significantly decreased. Results for granulocyte-macrophage colony-forming units and erythroid colonies showed a profound decrease immediately post-dosing, but a return to normal values was evident at day 50. Serum FL concentrations demonstrated very significant increases in the immediate post-dosing period, but a return to normal was seen at day 50 post-dosing; a relatively similar pattern was seen in the number of apoptotic femoral marrow nucleated cells. The histopathological examination of kidney tissues from MMC animals at day 42 and 50 post-dosing showed evidence of hydronephrosis with cortical glomerular/tubular atrophy and degeneration. It is therefore concluded that MMC administered on eight occasions over 18 days to female CD-1 mice at 2.5 mg/kg induced profound changes in haematological and bone marrow parameters in the immediate post-dosing period with a return to normal levels at day 50 post-dosing; however, there was evidence of mild but significant late-stage/residual effects on RBC and FNCC, and on cells of the erythroid lineage in the bone marrow.

Progression of Cisplatin-Induced Nephrotoxicity in a Carnitine-Depleted Rat Model

Background: This study has been initiated to investigate whether endogenous carnitine depletion and/or carnitine deficiency is an additional risk factor and/or a mechanism in cisplatin-induced nephrotoxicity and to gain insights into the possibility of a mechanism-based protection by L-carnitine against this toxicity. Methods: 60 male Sprague-Dawley rats were divided into six groups of 10 animals each and received one of the following treatments: The first three groups were injected intraperitoneally with normal saline, L-carnitine (500 mg/kg), and D-carnitine (750 mg/kg), respectively, for 10 successive days. The 4th, 5th, and 6th groups were injected intraperitoneally with the same doses of normal saline, L-carnitine and D-carnitine, respectively, for 5 successive days before and after a single dose of cisplatin (7 mg/kg). Six days after cisplatin treatment, the animals were sacrificed, and serum as well as kidneys were isolated and analyzed. Results: A single dose of cisplatin resulted in a significant increase in blood urea nitrogen (BUN), serum creatinine, malondialdehyde (MDA) and nitric oxide (NO) and a significant decrease in total carnitine, reduced glutathione (GSH) and adenosine triphosphate (ATP) content in kidney tissues. Interestingly, L-carnitine supplementation attenuated cisplatin-induced nephrotoxicity manifested by normalizing the increase of serum creatinine, BUN, MDA and NO and the decrease in total carnitine, GSH and ATP content in kidney tissues. In the carnitine-depleted rat model, cisplatin induced a progressive increase in serum creatinine and BUN as well as a progressive reduction in total carnitine and ATP content in kidney tissue. Histopathological examination of kidney tissues confirmed the biochemical data, i.e. L-carnitine supplementation protected against cisplatin-induced kidney damage, whereas D-carnitine aggravated cisplatin-induced renal injury. Conclusion: Data from this study suggest that: (1) oxidative stress plays an important role in cisplatin-induced kidney damage; (2) carnitine deficiency should be viewed as an additional risk factor and/or a mechanism in cisplatin-induced renal dysfunction, and (3) L-carnitine supplementation attenuates cisplatin-induced renal dysfunction.

Determination of selective biochemical variables in pregnant and lactating mice after stobadine administration

The aim of this study was to investigate the effects of the oral administration of stobadine (STB), a neuro- and cardioprotective drug with high antioxidant properties, on selective biochemical variables in pregnant and lactating mice. STB was administered orally at a dose of 50 mg/kg from day 15 of gestation to day 21 of lactation. Creatinine and urea were determined in serum, while acidity, proteins, glucose, ketones, bilirubin, urobilinogen, blood and creatinine were determined in urine from females on days 0, 15 and 18 of gestation and on days 7, 14, 21, and 28 postpartum (pp). In the biochemical variables investigated, no significant differences in STB-treated animals compared with controls were recorded on any of the days studied. Histopathological examination of kidney tissue did not reveal any adverse effect of STB administration.

Effect of Colchicine on Chronic Ciclosporin Nephrotoxicity in Sprague-Dawley Rats

Thirty male Sprague-Dawley rats were given ciclosporin (Cs) orally, 15 mg/kg daily for 80 days. Fifteen served as positive controls, while the other 15 were given daily colchicine at a dose of 30 µg/kg in addition to Cs. Additional 15 rats were given olive oil only and served as negative controls. The animals were subjected every other week to laboratory assessment of serum creatinine, sodium, potassium, and Cs whole-blood trough levels; also urine samples were examined for creatinine, sodium, potassium, and protein concentrations. At the end point, the animals were sacrificed, and kidney tissue was examined for histopathological changes. Comparing negative control versus Cs-treated and Cs-plus-colchicine-treated rats, there were no significant differences in serum creatinine, creatinine clearance, and serum and urine values of sodium and potassium as well as urinary protein/creatinine ratios. Yet histopathological examination of kidney tissues showed focal tubular atrophy and interstitial fibrosis in inner medulla and inner stripe of the outer medulla in all Cs-treated animals and in only 1 of the colchicine-treated group, but in none of the negative controls. Histological changes in other kidney zones in different animal groups were minor and not different. From this study, we may conclude that colchicine is of protective value against chronic Cs nephrotoxicity in Sprague-Dawley rats.

Effect of desferrioxamine on cisplatin-induced nephrotoxicity in normal rats.

Biochemical and histological evaluations of the effects of the iron chelator desferrioxamine on the nephrotoxicity induced by cisplatin in normal rats were carried out. A single dose of cisplatin (7.5 mg/kg, intravenously) caused nephrotoxicity that manifested biochemically as an elevation of blood urea nitrogen, serum creatinine and an increase in the kidney weight as a percent of body weight. Moreover, severe decreases in serum calcium and albumin were observed. Histopathological examination of kidney tissue revealed tubular necrosis with sloughing of tubular epithelium. Desferrioxamine treatment (250 mg/kg, intraperitoneally) 30 min before cisplatin administration does not protect the kidney from the damaging effects of cisplatin. A greater increase in blood urea nitrogen, serum creatinine and kidney weight was observed with significant tubular necrosis and a mild lymphocytic infiltrate. Desferrioxamine pretreatment decreased the lipid peroxidation induced by cisplatin but at the same time increased nonprotein sulfhydryl (-SH) concentrations in the kidney tissue. The findings of this study suggest that lipid peroxidation is not the main cause of cisplatin-induced nephrotoxicity and that desferrioxamine which was useful for prevention of cardiac and hematological damage induced by doxorubicin, aggrevated the cisplatin-induced nephrotoxicity. More investigations are needed to establish a definite assessment of its selectivity.

A streptococcal plasminogen activator in the focus of infection and in the kidneys during the initial phase of experimental streptococcal glomerulonephritis.

Strains of group A streptococci known to secrete the nephritis strain-associated protein (NSAP), a plasminogen activator, were studied for their ability to produce APSGN in rabbits. A tissue cage model was used to monitor the secretion of NSAP at the focus of infection and histopathological examination of kidney tissue was used to determine glomerular pathology. Animals infected with NSAP positive strains exhibited NSAP deposits in the glomerular tissue by day 7 in the absence of antibody to this molecule with progressive pathology indicative of APSGN three weeks later. Animals infected with the NSAP negative streptococcal strain exhibited no abnormal pathology. The ability of NSAP to bind to kidney tissue suggested that it has unique nephrotropic properties; and its ability to activate plasminogen to plasmin, possibly in situ, suggests that much of the pathological events associated with APSGN may be initiated by plasmin activity.