Effects of mycophenolate mofetil on cisplatin-induced renal dysfunction in rats

Purpose Inflammation and oxidative stress are important events among the plethora of mechanisms involved in cisplatin (CDDP)-induced nephrotoxicity. The aim of this study was to evaluate the effect of mycophenolate mofetil (MMF), an immunosuppressive, in the protection against CDDP-induced renal dysfunction. Methods Rats were divided into four groups; untreated-control group, CDDP-treated group (7 mg/kg, single intraperitoneal dose), MMF-treated group (40 mg/kg/day orally for 5 successive days) and the fourth group was treated with both drugs and MMF treatment was started 1 day prior to CDDP administration. Nephrotoxicity was assessed 7 days after the CDDP treatment by measuring serum indices of nephrotoxicity, kidney weight as a percentage of total body weight, kidney’s tissue peroxidative alterations and total nitrate/nitrite concentration (NOx) and the results were confirmed histopathologically. Results Rats treated with CDDP showed marked nephrotoxicity as evidenced from the significant increase in serum creatinine and urea levels and decrease in serum calcium and albumin levels. Kidneys of CDDP-treated rats showed significant increases in kidney weight and malondialdehyde (MDA) production level and decreases in total NOx concentration, glutathione peroxidase (GPx) activity and reduced glutathione (GSH) content levels. Histopathological assessment of kidneys of CDDP-treated rats revealed extensive tubular necrosis with “sloughing off” of the renal tubular lining cells, intratubular hyaline casts and mononuclear cell infiltration. Treatment with MMF significantly protected the rats against CDDP-induced nephrotoxicity. The rise in serum creatinine and urea levels, kidney weight and kidney tissue MDA production, depletion of “endogenous antioxidant reserve” including GPx activity and reduced GSH content levels and the deleterious histopathological changes induced by CDDP treatment were significantly mitigated by MMF treatment. Conclusions MMF treatment dramatically ameliorates CDDP-induced renal dysfunction.     

Effect of N-acetylcysteine route of administration on chemoprotection against cisplatin-induced toxicity in rat models

Dosing and route of administration of N-acetylcysteine (NAC) for protection against cisplatin (CDDP) nephrotoxicity was investigated in rats. Two models of toxicity were tested: a single high dose of CDDP (10 mg/kg intraperitoneally (IP)), and multiple low dose treatments (1 mg/kg IP twice a day for 4 days, 10 days rest, then repeated). NAC (50-1,200 mg/kg) was given to the rats by IP, oral (PO), intravenous (IV) and intra-arterial (IA) routes. Renal toxicity was determined by blood urea nitrogen (BUN) and creatinine (CR) levels 3 days after treatment. Blood collected 15 min after NAC was analyzed for total NAC. Both models of CDDP administration produced renal toxicity. In the single dose CDDP model, NAC 400 mg/kg given IP and PO produced no renal protection as measured by BUN (131.8 +/- 8.2 and 123.3 +/- 8.2, respectively) or CR (2.3 +/- 0.38 and 1.77 +/- 0.21, respectively). IV NAC reduced nephrotoxicity, (BUN 26.3 +/- 6.8, CR 0.47 +/- 0.15). NAC 50 mg/kg IA gave better protection than IV. In the repeated-dose CDDP model, nephrotoxicity was blocked by 800 mg/kg NAC given IV but not IP. Blood concentrations of total NAC showed a dose response after IV NAC, but high dose NAC (1,200 mg/kg) by the PO route gave very low levels of NAC. Thus the protective properties of NAC are affected by the dose and route of administration.     

Age and Gender Related Renal Side Effects of Cisplatin in Animal Model

Backgrounds: Cisplatin (CDDP) is a choice of anti-cancer drug for cancer chemotherapy with serious side effects such as nephrotoxicity. It seems that age is an important factor influencing the side effects of CDDP. This study was designed to determine the role of age and gender simultaneously in CDDP induced renal toxicity. Methods: 40 Wistar male and female rats were assigned as 6 groups in 3 different age categories (10, 16, and 20 weeks old). The single dose of CDDP (7.5 mg/kg, ip) was administrated, and a week later measurements were performed. Results: Body weight changes in male (not in female) animals aged 16 and 20 weeks were more than 10 weeks old animals (P<0.05). In male rats, the serum levels of creatinine (Cr) and blood urea nitrogen (BUN), and Cr-clearance in aged 10 weeks, normalized kidney weight (KW) in aged 20 weeks, and serum nitrite, aspartate aminotransferase (AST) and malondialdehyde (MDA) levels and kidney tissue damage score (KTDS) in rats aged 16 weeks were significantly altered (P<0.05). Gender difference in serum level of Cr, BUN and nitrite, and Cr-clearance were observed in animals aged10 weeks (P<0.05). Conclusion: The side effects of CDDP are gender depended, and may be different at various ages.     

Protective effect of L-carnitine versus amifostine against cisplatin-induced nephrotoxicity in rats

We aimed to compare the protective effect of L-carnitine (CAR) and amifostine (AMF) against cisplatin (CDDP)-induced nephrotoxicity through biochemical markers and histopathological evaluation. Fifty-seven Wistar albino male rats were randomly classified into six groups, which were AMF+CDDP (n = 11; 200 mg/kg AMF 30 min prior to 7 mg/kg CDDP), CAR+CDDP (n = 11; 300 mg/kg CAR 30 min prior to 7 mg/kg CDDP), CDDP (n = 11; 1 mL/kg isotonic saline 30 min prior to 7 mg/kg CDDP), AMF (n = 8; 200 mg/kg AMF alone), CAR (n = 8; 300 mg/kg CAR alone), and control (n = 8; 1 mL/kg isotonic saline alone). All drugs were given intraperitoneally. Five days after medication, animals were killed, and samples of blood and kidney tissues were collected for biochemical and histopathological evaluation. The serum urea level was highest in AMF+CDDP group among CDDP-applied groups without statistical significance (median, range: 88, 56-21 mg/dL; P > 0.05). There was no statistical significance among CDDP-applied groups in terms of creatinine level (P > 0.05). In the AMF+CDDP group, the median glomerular, tubular, and tubulointerstitial inflammatory damage scores were significantly higher than the other CDDP-applied groups (P < 0.001). The difference between CAR+CDDP and CDDP groups was not statistically significant in terms of renal damage scores. AMF+CDDP group had significantly higher median total nephrotoxicity score than all the other groups (P < 0.001). To conclude, AMF or CAR has no protective effect on CDDP-induced nephrotoxicity. Furthermore, our findings suggest that application of AMF before CDDP may enhance CDDP-induced nephrotoxicity histopathologically.     

2, 4-二氯苯氧乙酸对子代大鼠发育及脑组织的氧化损伤作用

目的:研究大鼠孕期和哺乳期暴露2,4-二氯苯氧乙酸(2,4-D)对子代发育及脑组织脂质过氧化的损伤作用。方法:Wistar大鼠于受孕后第2天开始经口灌胃染毒2,4-D(0、25、50和100 mg/kg)直至仔鼠出生后第21天,每天1次,连续42 d。期间检测仔鼠生理及早期神经行为发育指标。断乳1周后处死仔鼠检测脑组织丙二醛(MDA)、还原型谷胱甘肽(GSH)的含量及谷胱甘肽过氧化物酶(GSH-Px)的活力。结果:与对照组相比,100 mg/kg剂量组仔鼠体质量从出生后14 d开始降低,50 mg/kg剂量组仔鼠体质量从出生后21 d开始降低,差异均有统计学意义(P<0.05),而其他各生理发育指标差异均无统计学意义(P>0.05)。神经行为测试中100 mg/kg剂量组仔鼠断崖回避、空中翻正及听觉惊愕的阳性发生率均明显低于对照组(P<0.05),出现神经行为发育迟缓。50和100 mg/kg剂量组仔鼠脑组织中MDA含量升高,100 mg/kg剂量组仔鼠脑组织GSH含量及GSH-Px的活性下降,与对照组相比差异均有统计学意义(P均<0.05)。结论:大鼠孕期和哺乳期暴露2,4-D致子代神经发育迟缓可能与2,4-D引起脑组织脂质过氧化损伤有关。     

Quantitative relationship between pharmacokinetics of unchanged cisplatin and nephrotoxicity in rats: importance of area under the concentration-time curve (AUC) as the major toxicodynamic determinant in vivo

 Purpose: The major pharmacokinetic parameters of unchanged cisplatin (CDDP) related to nephrotoxicity were evaluated in rats in vivo using a pharmacodynamic model. Methods: CDDP was administered according to various dosing schedules (single bolus, intermittent bolus, or continuous infusion). Unchanged CDDP in plasma and urine was quantified using high-performance liquid chromatography (HPLC). The pharmacokinetics were assessed by model-independent methods. The relationship between pharmacokinetics and BUN levels was evaluated using a sigmoid maximum response (E_max) model. Results: Unchanged CDDP showed linear pharmacokinetics after single bolus injections of 1 to 5 mg/kg CDDP. Nephrotoxicity was ameliorated following intermittent bolus injection (1 mg/kg per day for 5 days) and continuous infusions (over 2 and 3 h) of the same CDDP doses (5 mg/kg), although these dosing schedules did not change the area under the concentration-time curve (AUC), total clearance (Clt), urinary excretion of unchanged CDDP or kidney platinum levels significantly. The maximum BUN level, as a nephrotoxicity marker, showed dose-related increases after single bolus injection of 1 to 5 mg/kg CDDP and after 3-h infusion of 5 to 25 mg/kg. The pharmacodynamic relationship between the maximum BUN level and C_max and between the maximum BUN level and AUC were apparently different between single bolus injection and 3-h infusion. The maximum BUN level was related to the AUC calculated by plasma concentrations of unchanged CDDP greater than the threshold level (AUC_>Cmin), a relationship most successfully described by the signoid E_max model, regardless of CDDP dose and schedule. The plasma threshold level of unchanged CDDP was determined as 0.9 μgPt/ml in rats. Conclusions: The present results substantiated the importance of C×T (AUC) value as an indicator of CDDP-induced nephrotoxicity in vivo as well as of tumor cell-killing effect of CDDP in vitro. The AUC_>Cmin of unchanged CDDP was found to be an important pharmacokinetic parameter predicting CDDP nephrotoxicity. Received: 12 February 1996 / Accepted: 5 September 1996     

Cardioprotective effects of fullerenol C(60)(Oh)(24) on a single dose doxorubicin-induced cardiotoxicity in rats with malignant neoplasm

The therapeutic utility of the anthracycline antibiotic doxorubicin is limited due to its cardiotoxicity. Our aim was to investigate the efficacy of fullerenol C(60)(OH)(24) in preventing single, high-dose doxorubicin-induced cardiotoxicity in rats with malignant neoplasm. Experiment was performed on adult female Sprague Dawley rats with chemically induced mammary carcinomas. The animals were sacrificed two days after the application of doxorubicin and/or fullerenol, and the serum activities of CK, LDH and alpha-HBDH, as well as the levels of MDA, GSH, GSSG, GSH-Px, SOD, CAT, GR, and TAS in the heart, were determined. The results obtained from the enzymatic activity in the serum show that the administration of a single dose of 8 mg/kg in all treated groups induces statistically significant damage. There are significant changes in the enzymes of LDH and CK (p < 0.05), after an i.p. administration of doxorubicin/fullerenol and fullerenol. Comparing all groups with untreated control group, point to the conclusion that in the case of a lower alpha-HBDH/LDH ratio, results in more serious the liver parenchymal damage. The results revealed that doxorubicin induced oxidative damage and that the fullerenol antioxidative influence caused significant changes in MDA, GSH, GSSG, GSH-Px, SOD, CAT, GR, and TAS level in the heart (p < 0.05). Therefore, it is suggested that fullerenol might be a potential cardioprotector in doxorubicin-treated individuals.     

Toxicological and Tumoricidal Evaluations of a New Platinum Complex, (–)-(R)-2-Aminomethy lpyrrolidine (1,1-cyclobutanedicarboxylato) platinum (II) Monohydrate, in Rats

The toxicities and antitumor activity of a new anticancer platinum compound, (-)-( R )-2-amino-methylpyrrolidine(l,l-cyclobutanedicarboxylato)platinum(II) monohydrate (DWA2114R), were examined in rats by single intravenous injection in comparison with those of cis -diammine(1,1-cyclobutanedicarboxylato)platinum(II) (CBDCA) and cis diamminedichloroplatinum(II) (CDDP). The lethal dose (LD) of DWA2114R (100 mg/kg) or CBDCA (80 mg/kg) caused a slight decrease in body weight <10%) and no significant change in the levels of blood urea nitrogen and urinary sugar and protein. In contrast, a sub-LD level of CDDP (8 mg/kg) seriously decreased body weight (20%) and markedly elevated the levels of these nephrotoxicity parameters. Monitoring the numbers of peripheral blood cells for 3 weeks after the drug injection revealed that all three drugs showed severe thrombocytopenia, moderate leukopenia and slight anemia. However, CBDCA induced the most severe thrombocytopenia among these drugs. The number of platelets was reduced by 60% in rats injected with a half LD of CBDCA. A moderate reduction in platelet count (35–43%) was caused by an equitoxic dose of DWA2114R or CDDP, but abated about 3 days faster than that caused by CBDCA. Interestingly, only CDDP caused an irreversible anemia. Each drug showed a potent antitumor activity at weakly toxic doses against Walker 256 carcinosarcoma transplanted intramuscularly into rats. These results indicate that DWA2114R could be a promising new platinum anticancer agent with an improved toxicity profile.     

阿尔泰金莲花浸膏粉对PM2.5致大鼠急性肺损伤的保护作用

目的：研究阿尔泰金莲花浸膏粉（TAEP）对PM2.5致大鼠急性肺损伤（ALI）的保护作用。方法：60只SD大鼠随机分为正常对照组（生理盐水）,模型组,TAEP 125、250、500 mg/kg组,地塞米松（2 mg/kg）阳性对照组,每组10只。各剂量组按相应剂量每天灌胃1次给予受试物,连续30 d,除正常对照组外,其余各组根据预实验结果,在第30天按14 mg/kg行气管滴注PM2.5（采样于乌鲁木齐市）悬液,造成大鼠急性肺损伤。造模3 h后,经大鼠腹主动脉取血,进行白细胞分类计数并检测血清中乳酸脱氢酶（LDH）、超氧化物歧化酶（SOD）、谷胱甘肽（GSH）、丙二醛（MDA）、一氧化氮（NO）、白介素-6（IL-6）、白介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）的含量;取大鼠右肺上叶作病理组织学检查,下叶称取质量后计算肺湿/干质量比（W/D）,取大鼠左肺行肺泡灌洗,并收集肺泡灌洗液（BALF）,检测其中IL-6、IL-1β、TNF-α的含量。结果：与正常对照组比较,模型组大鼠外周血白细胞计数,血清和BALF中IL-6、IL-1β、TNF-α含量升高（P均 < 0.01）,血清中LDH、MDA、NO含量升高（P均 < 0.01）,肺组织W/D升高（P均 < 0.01）,SOD和GSH含量降低（P均 < 0.01）;与模型组比较,TAEP各剂量组大鼠外周血白细胞计数,血清和BALF中IL-6、IL-1β、TNF-α含量降低（P均 < 0.05或0.01）,血清中LDH、MDA、NO含量降低（P均 < 0.05或0.01）,肺组织W/D降低（P均 < 0.05或0.01）,SOD和GSH含量升高（P均 < 0.05或0.01）;TAEP 500 mg/kg组各项检测指标与地塞米松组接近（P均 > 0.05）,病理检查结果显示随TAEP剂量增加大鼠肺泡形态结构破坏降低,水肿及炎症细胞浸润减少,TAEP 500 mg/kg组大鼠肺脏可见少量炎细胞浸润,肺泡及各级支气管均结构完整,与地塞米松组相近。结论：TAEP对PM2.5致大鼠急性肺损伤具有一定的保护作用。     

Toxicological and tumoricidal evaluations of a new platinum complex, (-)-(R)-2-aminomethylpyrrolidine(1,1-cyclobutanedicarboxylato+ ++)platinum( II) monohydrate, in rats

The toxicities and antitumor activity of a new anticancer platinum compound, (-)-(R)-2-aminomethylpyrrolidine(1,1-cyclobutanedicarboxylato++ +) platinum(II) monohydrate (DWA2114R), were examined in rats by single intravenous injection in comparison with those of cis-diammine(1,1-cyclobutanedicarboxylato)platinum(II) (CBDCA) and cis-diamminedichloroplatinum(II) (CDDP). The lethal dose (LD) of DWA2114R (100 mg/kg) or CBDCA (80 mg/kg) caused a slight decrease in body weight (less than 10%) and no significant change in the levels of blood urea nitrogen and urinary sugar and protein. In contrast, a sub-LD level of CDDP (8 mg/kg) seriously decreased body weight (20%) and markedly elevated the levels of these nephrotoxicity parameters. Monitoring the numbers of peripheral blood cells for 3 weeks after the drug injection revealed that all three drugs showed severe thrombocytopenia, moderate leukopenia and slight anemia. However, CBDCA induced the most severe thrombocytopenia among these drugs. The number of platelets was reduced by 60% in rats injected with a half LD of CBDCA. A moderate reduction in platelet count (35-43%) was caused by an equitoxic dose of DWA2114R or CDDP, but abated about 3 days faster than that caused by CBDCA. Interestingly, only CDDP caused an irreversible anemia. Each drug showed a potent antitumor activity at weakly toxic doses against Walker 256 carcinosarcoma transplanted intramuscularly into rats. These results indicate that DWA2114R could be a promising new platinum anticancer agent with an improved toxicity profile.     

Protection against cisplatin-induced nephrotoxicity by Spirulina in rats

Purpose: Cisplatin (CP)-induced nephrotoxicity is associated with the increased generation of reactive oxygen metabolites and lipid peroxidation in kidney, caused by the decreased levels of antioxidants and antioxidant enzymes. The purpose of this study was to evaluate the role of Spirulina, blue–green alga with antioxidant properties, in the protection of cisplatin-induced nephrotoxicity in rat. Methods: Rats were treated with CP (6 mg/kg bw, single dose, intraperitoneally). Spirulina (1,000 mg/kg) was administered orally for 8 days and CP treatment was given on day 4. Nephrotoxicity was assessed, 6 days after the CP treatment, by measuring plasma urea, creatinine, urinary N-acetyl-(d-glucose-aminidase) (β-NAG) and histopathology of kidney. Results: Rats treated with CP showed marked nephrotoxicity as evidenced from the significant elevation in plasma urea, creatinine and urinary β-NAG. Histological assessment revealed marked proximal tubular necrosis and extensive epithelial vacuolization in the kidney of CP-treated rats. Superoxide dismutase, catalase and glutathione peroxidase were decreased and lipid peroxidation was increased in kidney tissue. Pretreatment with Spirulina protected the rats from CP-induced nephrotoxicity. The rise in plasma urea, creatinine, urinary β-NAG, plasma and kidney tissue MDA and histomorphological changes were significantly attenuated by Spirulina. In vitro studies using human ovarian cancer cells revealed that Spirulina did not interfere with the cytotoxic effects of CP on tumor cells. Conclusions: In summary, Spirulina significantly protected the CP-induced nephrotoxicity through its antioxidant properties.     

Pu-erh Tea Powder Preventive Effects on Cisplatin-Induced Liver Oxidative Damage in Wistar Rats

Background: Chemotherapy is one of the major means for control of malignancies, with cisplatin (CDDP) as one of the main agents, widely used for the treatment of various malignant solid tumors. However, prevention of hepatotoxicity from cisplatin is one of the urgent issues in cancer chemotherapy. In this study, we aimed to investigate the effects of pu-erh tea on hepatotoxicity through body weight and tissue antioxidant parameters like, liver coefficient, serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), malondialdehyde(MDA) and glutathione (GSH) levels, and light microscopic evaluation by histological findings. Materials and Methods: The rats were randomly divided into five groups: Control (n=10), cisplatin (3 mg/kg p.i., n=10), cisplatin+pu-erh (0.32 g/kg/day i.g., n=10), cisplatin+pu-erh (0.8 g/kg/day i.g., n=10) and cisplatin+pu-erh (1.6 g/kg/day i.g., n=10). Pu-erh tea powderwas administrated for 31 consecutive days. The rats were sacrificed at the end on the second day after a single dose of cisplatin treatment for measuring indices. Results: Pu-erh tea powder exhibited a protective effect by decreasing MDA and GSH and increasing the SOD and GSH-PX levels and GSH-PX/MDA ratio in camparison with the control group. Besides, pu-erh tea was also able to alleviate the pathological damage to some extent. Conclusion: Pu-erh tea powder is protective against cisplatin-induced liver oxidative damages, especially at themedium dosage (0.8 g/kg/d).     

Relationship between pharmacokinetics of unchanged cisplatin and nephrotoxicity after intravenous infusions of cisplatin to cancer patients

 Purpose: The relationships between pharmacokinetic parameters of unchanged cisplatin (CDDP) and several markers for nephrotoxicity after CDDP infusion (80 mg/m²) over 2 and 4 h were quantitated in patients with various cancers (lung, stomach and colon cancers and mediastinal tumor). Methods: Plasma and urinary levels of unchanged CDDP were measured using a specific high-performance liquid chromatography method. Pharmacokinetic parameters were calculated according to the model-independent method. The nephrotoxicity markers, blood urea nitrogen (BUN), serum creatinine (SCr), plasma and urinary β₂-microglobulin (BMG_p and BMG_u), urinary N-acetyl-β-D-glucosaminidase (NAG) and creatinine clearance (CCR) were monitored for 30 days following CDDP administration. Results: The maximum plasma concentration (C_max), maximum urinary excretion rate (dAe/dt_max), area under the plasma concentration-time curve from time zero to infinity (AUC), cumulative amount excreted in urine from time zero to infinity (Ae), total clearance (Clt), renal clearance (Clr) and plasma half-life (t_1/2) of unchanged CDDP were not significantly different between the 2-h and 4-h infusion schedules. The values of the nephrotoxicity markers changed significantly following CDDP administration, suggesting that CDDP chemotherapy (80 mg/m²) caused nephrotoxicity. The C_max of unchanged CDDP was the most informative pharmacokinetic parameter for nephrotoxicity. C_max was related to maximum BUN, maximum SCr and minimum CCR levels in 27 CDDP treatments according to an exponential model. Conclusion: In order to attain more effective CDDP chemotherapy with minimum nephrotoxicity, the present pharmacokinetic and pharmacodynamic studies suggest that the C_max or steady-state plasma level of unchanged CDDP should be maintained between 1.5 and 2 μg/ml in a standard continuous infusion schedule over 2 h and 4 h. Received: 2 May 1995/Accepted: 25 March 1996     

Optimal duration of whole body hyperthermia when combined with cis-diamminedichloroplatinum(II)

We examined the optimal duration of whole body hyperthermia (WBH, 41.5 degrees C) when administered simultaneously with cis-diamminedichloroplatinum(II) (CDDP) using F344 rat fibrosarcoma model. The antitumor efficacy was measured by tumor growth delay (TGD) and nephrotoxicity was evaluated by the day 5 blood urea nitrogen (BUN) associated with different duration of WBH (0.5, 1, 1.5, 2 or 3 h) with a constant dose of CDDP (2 mg/kg i.v. bolus). There was significant increase in TGD from 2.8 days to 5.4 days when the WBH duration was increased from 0.5 to 1 h (p<0.001). CDDP-induced nephrotoxicity was also enhanced by WBH. We estimated specific therapeutic efficacy (STE) for each treatment using the ratio of antitumor effect measured by TGD to nephrotoxicity calculated from the degree of increment of BUN. CDDP combined with 1 h WBH produced the best STE of 2.2. We conclude, that to maximize the therapeutic gain, a 1 h duration is optimal in the present setting of thermochemotherapy.     

齐墩果酸对酒精诱导的大鼠胃壁氧化损伤的保护作用

目的：研究化学单体齐墩果酸（OA）对酒精诱导的大鼠胃壁损伤的保护作用。方法：采用随机数表法将24只SD大鼠随机分为对照组（等热量葡萄糖溶液）、酒精暴露组（灌胃给予4 g/kg酒精构建酒精性胃壁损伤模型）、OA干预组（灌胃给予溶解了10 mg/kgOA的酒精溶液进行干预），共3组，每组8只，持续30 d。观察OA对酒精诱导的大鼠胃壁损伤是否具有保护作用。检测胃壁大体改变和HE病理变化；胃壁组织丙二醛（MDA）和氧化型谷胱甘肽（GSSG）含量；还原型谷胱甘肽（GSH）含量及GSH/GSSG比值，抗氧化酶转录因子Nrf-2的mRNA和蛋白表达；TNF-α、IL-6的mRNA和蛋白表达水平。结果：与对照组相比，4 g/kg的酒精暴露30 d可以成功诱导大鼠胃壁氧化损伤和炎症反应。与酒精暴露组大鼠相比，OA干预组的胃壁病理损伤程度减轻，胃壁组织MDA、GSSG含量减少（P < 0.05），GSH含量和GSH/GSSG比值增加（P < 0.05），Nrf-2的mRNA和蛋白表达水平显著升高（P < 0.05），同时TNF-α、IL-6的mRNA和蛋白表达降低（P < 0.05）。结论：OA可以通过抗氧化和抗炎作用发挥对酒精诱导大鼠胃壁损伤的保护作用。     

Increased therapeutic effect on metastatic liver tumors in rats of two-route chemotherapy usingcis-diamminedichloroplatinum (II) and its antidote,sodium thiosulfate,with temporary clamping of the abdominal aorta

Summary To improve the therapeutic effects of conventional “two-route chemotherapy” (TRC) comprisingcis-diamminedichloroplatinum(II) (CDDP) given via the hepatic artery plus simultaneous i. v. sodium thiosulfate (STS) on metastatic liver tumors in rats, we combined TRC with aortic clamping at the supraceliac level. Treatments were evaluated in Wistar-King-Aptekman (WKA) rats bearing metastatic liver tumors 7 days after the inoculation of 10⁶ syngenic RBT-1 (transitional-cell carcinoma) cells via the mesenteric vein. When 15 mg/kg CDDP was injected i. a. over 5 min, immediately followed by STS 1,580 mg/kg (200-fold the molar equivalent of 15 mg/kg CDDP) given i. v. over a further 5 min, the antitumor activity, evaluated by the number of tumor nodules present 12 days after treatment, was superior to that of conventional TRC (15 mg/kg i. a. CDDP plus simultaneous administration of 1,580 mg/kg i. v. STS), but the blood urea nitrogen (BUN) level was highly elevated (63.6 mg/dl). With aortic clamping for 7.5 min during CDDP administration and the first half of STS treatment, the TRC consisting of CDDP plus delayed STS (modified TRC) exhibited a further improvement in antitumor activity, with no nephrotoxicity (BUN, 17.1 mg/dl). Although the antitumor activity of 3 or 5 mg/kg i. a. CDDP was also increased by aortic clamping, in animals with normal BUN levels the survival of those treated with modified TRC was greater than that of rodents given 3 mg/kg i. a. CDDP with aortic clamping; however, the former was the same as that of animals given 5 mg/kg i. a. CDDP with aortic clamping whose BUN levels were elevated (31.2 mg/dl). Loss of body weight, the decrease in WBC counts, and changes in the serum transaminase levels in rats given modified TRC were tolerable. The improved therapeutic effect of modified TRC can be explained as follows: during aortic clamping, (a) CDDP delivery to the kidney decreased by 96% and made feasible the delay in STS administration after CDDP without nephrotoxicity, and (b) CDDP retention in the liver was increased by 366%, as aortic clamping decreased the portal blood flow, thereby inhibiting the washout of CDDP from the liver. This study was supported in part by a Grant-in-Aid for Cancer Research from the Ministry of Education, Science and Culture, Japan     

Experimental study of the protective effect of glutathione against cisplatin-induced nephrotoxicity

Glutathione (GSH) is the most important intracellular thiol-compound which participates in the detoxification mechanisms of the cell. Its high affinity to react with platinum complexes would give rise to lower or non-toxic metabolites and prevent cisplatin nephrotoxicity. In order to determine if GSH can protect against cisplatin-induced renal toxicity, 120 female Wistar rats received LD-100 or LD-50 of cisplatin with or without GSH, at two different dose levels and by two different routes. Biochemical and histological changes as survival was observed in each group. The administration of GSH did not modify cisplatin LD-100. When cisplatin LD-50 was used, a significant improvement in the survival rate was observed in the group which received GSH as chemoprotector (100% vs 40%). The average values of urea and creatinine were significantly lower in the group treated with GSH (115 vs 370 mg/dl and 1.07 vs 4.02 mg/dl respectively). The degree of the tissue injury was also lower in the GSH group. The administration of GSH prior to cisplatin reduces its nephrotoxicity in this animal model. Further clinical trials are necessary to verify this protective effect when cisplatin is used as a cyclic administration and at different dose levels.     

Effects of sodium thiosulfate on the pharmacokinetics of unchanged cisplatin and on the distribution of platinum species in rat kidney: protective mechanism against cisplatin nephrotoxicity

To investigate the mechanism underlying the protective effect against cisplatin (CDDP) nephrotoxicity of its antidote, sodium thiosulfate (STS), the effects of STS on the pharmacokinetics of unchanged CDDP and on the distribution of unchanged CDDP and high and low molecular mass metabolites (fixed and mobile metabolites) in the kidney 1 min after a bolus injection of CDDP (5 mg/kg) to rats were studied. A decrease in the plasma concentration of unchanged CDDP and an increase in the plasma concentration of mobile metabolites were observed in the rats after the bolus injection of CDDP in combination with STS infusion for 30 min (1200 mg/kg). Although STS accelerated platinum excretion during the first 10 min after CDDP injection, unchanged CDDP was not excreted in the urine in the STS-treated rats. Total kidney platinum 1 min after the bolus injection of CDDP was detected mainly as unchanged CDDP (86% of the total platinum) in the rats given CDDP alone. However, in the STS-treated rats, the total kidney platinum was decreased to 62% of the level in the rats given CDDP alone, and the platinum species detected in the kidney were mainly mobile metabolites. Only 24% of the total kidney platinum was detected as unchanged CDDP in the STS-treated rats. The loss of body weight and increases in BUN and serum creatinine levels usually observed after a bolus injection of CDDP were completely prevented by STS coadministration. The present study provides information about unchanged CDDP pharmacokinetics and the distribution of unchanged CDDP and some of its generic metabolites in the kidney when STS is coadministered as an antidote. These results show that the protective effect of STS against CDDP nephrotoxicity can be attributed to the formation of inactive mobile metabolites by a direct reaction between unchanged CDDP and STS in the systemic circulation, resulting in a reduction in the amount of unchanged CDDP in the kidney.     

沉默G6PD对卵巢癌细胞顺铂敏感性的影响及其作用机制

目的 探讨葡萄糖-6-磷酸脱氢酶（glucose-6-phosphate dehydrogenase，G6PD）在卵巢癌细胞顺铂耐药中的作用及其潜在的机制。方法 通过低浓度加量持续诱导法构建卵巢癌顺铂耐药细胞株A2780/CDDP，采用Label-free定量蛋白质组学法分析A2780和A2780/CDDP细胞差异蛋白G6PD，Western blot和RT-qPCR检测G6PD表达情况。通过siRNA技术将siRNA-G6PD及其阴性对照（siRNA-NC）转染至A2780/CDDP细胞，然后采用Western blot验证G6PD基因沉默效果，MTT法检测细胞增殖情况，流式细胞术检测细胞凋亡情况，流式细胞仪和酶标仪检测铁死亡相关物质活性氧（ROS）、丙二醛（MDA）、还原型谷胱甘肽（GSH）和脂质过氧化物的表达水平。结果 与A2780细胞相比，A2780/CDDP细胞中有95个上调蛋白和102个下调蛋白，其中上调蛋白中以G6PD表达差异最为显著；这些蛋白大多富集在代谢通路，且其功能主要与细胞氧化应激反应、核糖磷酸代谢途径相关。与A2780细胞相比，A2780/CDDP细胞中G6PD mRNA和蛋白表达水平均显著升高（均P<0.05），铁死亡相关物质ROS、MDA和脂质过氧化物水平均降低（均P<0.05），而GSH水平升高（P=0.001）。沉默G6PD后的A2780/CDDP细胞中顺铂的IC₅₀值降低（P=0.012），细胞凋亡率升高（P=0.006），铁死亡相关物质ROS、MDA和脂质过氧化水平均升高（均P<0.05），而GSH水平降低（P=0.007）。结论 沉默G6PD可能通过诱导卵巢癌顺铂耐药细胞A2780/CDDP中的铁死亡水平而增强顺铂敏感性。     

Protection against cisplatin-induced nephrotoxicity by recombinant human erythropoietin

Cisplatin (CDDP) is a potent nephrotoxin, and nephrotoxicity is its most important dose-limiting toxicity. In this study, we aimed to investigate the role of recombinant human erythropoietin (rhEPO) in the protection of cisplatin-induced nephrotoxicity and compare its efficacy with the cell-protective agent amifostine. All experiments were conducted on female Wistar albino rats. Animals were randomly assigned to four groups, each including six rats. Group A received only CDDP, group B received CDDP plus rhEPO, group C received CDDP plus amifostine, and group D received only rhEPO. At the end of 7 wk, hemoglobin (Hgb), hematocrite (Htc), blood urea nitrogen (BUN), and creatinine (Cr) levels were determined and kidneys of the rats were removed. The weights of the kidneys were measured and sent for histopathological examination. Proximal tubules from four areas of the kidney (outer cortex, inner cortex, the medullary ray, and outer stripe of outer medulla [OSOM]) were evaluated. There were statistically significant differences among the groups in terms of tubular scores, including overall renal tubular score, cortex, inner cortex, OSOM, and medullary ray tubular scores, and Htc levels. Group A rats had the worse tubular scores in all categories when compared to group D rats. When the results of groups B and C were compared, there were no differences in terms of BUN, Cr levels, and tubular scores, but the Htc level was significantly higher in group B. Group B rats had better overall and OSOM tubular scores when compared to group A. Group C also had better overall and OSOM tubular scores compared to group A. The present study showed for the first time that rhEPO plays an important role in the prevention of cisplatin-induced nephrotoxicity and it is as effective as amifostine.