Urinary enzyme excretion as a parameter for detection of acute renal damage mediated by N-(3,5-dichlorophenyl)succinimide (NDPS) in Fischer 344 rats

Comparative clinical evaluation of Boerhavia diffusa root extract with standard Enalapril treatment in Canine chronic renal failure

BACKGROUND

Complementing herbal drugs with conservative modern treatment could improve renal condition in canine chronic renal failure (CRF).

OBJECTIVE

In this study, clinical evaluation of Boerhavia diffusa root extract was carried out in CRF in dogs in comparison with standard enalapril.

MATERIALS AND METHODS

A total of 20 dogs of mixed breeds suffering from CRF from 1 to 2 months were divided into two groups (n = 10) and treated as follows: Group I - Enalapril at 0.5 mg/kg p.o. once daily for 90 days + amoxicillin and cloxacillin at 25 mg/kg i.m. once daily for 1-week; Group II - B. diffusa root extract at 500 mg p.o per dog daily for 90 days. Both groups were maintained on a supportive fluid therapy. The data were analyzed using paired t-test and one-way ANOVA followed by Dunnett's post-hoc test.

RESULTS

CRF caused a significant (P < 0.05) increase in systolic and diastolic blood pressure, serum creatinine, urea nitrogen, sodium, potassium, phosphorus, urinary protein, alkaline phosphatase (ALP), and glutamyl transferase (GGT). A significant (P < 0.05) decrease in hemoglobin and total erythrocyte count (TEC) was also observed. Nephrosonography revealed indistinct corticomedullary junction, altered renal architecture, hyper-echoic cortex, medulla, and sunken kidneys. Both the treatments significantly (P < 0.05) reduced systolic and diastolic blood pressure by day 30. Serum Creatinine, urea nitrogen, phosphorus, urinary protein, ALP, and GGT showed significant (P < 0.05) reduction by day 60 in both the treatments. However, potassium levels were normalized only by B. diffusa root extract treatment by day 30. Both the treatments failed to show a significant improvement in nephrosonographic picture even after 90 days posttreatment.

CONCLUSION

In conclusion, the efficacy of B. diffusa root extract was comparable to standard enalapril treatment of CRF in dogs.

Agonistic behavior in males and females: effects of an estrogen receptor beta agonist in gonadectomized and gonadally intact mice

Affiliative and agonistic social interactions are mediated by gonadal hormones. Research with estrogen receptor alpha (ERalpha) or beta (ERbeta) knockout (KO) mice show that long-term inactivation of ERalpha decreases, while inactivation of ERbeta increases, male aggression. Opposite effects were found in female alphaERKO and betaERKO mice. The role of acute activation of ERalpha or ERbeta in the agonistic responses of adult non-KO mice is unknown. We report here the effects of the ERbeta selective agonist WAY-200070 on agonistic and social behavior in gonadally intact and gonadectomized (gonadex) male and female CD-1 mice towards a gonadex, same-sex intruder. All 15min resident-intruder tests were videotaped for comprehensive behavioral analysis. Separate analyses assessed: (1) effects of WAY-200070 on each sex and gonadal condition; (2) differences between sexes, and between gonadally intact and gonadex mice, in untreated animals. Results show that in gonadally intact male and female mice, WAY-200070 increased agonistic behaviors such as pushing down the intruder and aggressive grooming, while leaving attacks unaffected. In untreated mice, males attacked more than females, and gonadex animals showed less agonistic behavior than same-sex, gonadally intact mice. Overall, our detailed behavioral analysis suggested that in gonadally intact male and female mice, ERbeta mediates patterns of agonistic behavior that are not directly involved in attacks. This suggests that specific aspects of aggressive behavior are acutely mediated by ERbeta in adult mice. Our results also showed that, in resident-intruder tests, female mice spend as much time in intrasexual agonistic interactions as males, but use agonistic behaviors that involve extremely low levels of direct attacks. This non-attack aggression in females is increased by acute activation of ERbeta. Thus, acute activation of ERbeta similarly mediates agonistic behavior in adult male and female CD-1 mice.

Metabolism of the nephrotoxicant N-(3,5-dichlorophenyl)succinimide in rats: evidence for bioactivation through alcohol-O-glucuronidation and O-sulfation

The agricultural fungicide, N-(3,5-dichlorophenyl)succinimide (NDPS), was shown to be nephrotoxic in rats. Previous studies have indicated that the metabolism of NDPS contributes to its mechanism of toxicity and both phase I and phase II pathways may be involved. In the current report, we investigated the detailed biotransformation of [(14)C]NDPS in rats using HPLC-ESI-MS. The chemical reactivity of the phase II NDPS metabolites was also evaluated. In vivo studies were conducted by administering [(14)C]NDPS to male Fischer 344 rats. Urine, tissue (liver and kidney), and plasma samples were analyzed. The mechanism of formation and chemical reactivity of the glucuronide and sulfate metabolites of NDPS were investigated in vitro using liver subcellular preparations. Major in vivo metabolites of NDPS were identified as the oxidative [N-(3,5-dichlorophenyl)-2- and 3-hydroxysuccinamic acid, 2-/3-NDHSA] and hydrolytic products [N-(3,5-dichlorophenyl)succinamic acid]. N-Acetylcysteine and cysteine (with intramolecular aminolysis) conjugates were also detected in rat urine and fecal extracts, respectively, suggesting the formation of reactive intermediate(s) in the metabolism of NDPS. Small amounts of the alcohol-O-glucuronide and O-sulfate of 2-/3-NDHSA were detected in rat urine, plasma, and tissue homogenates. The formation of these phase II metabolites was found to be mediated through the initial conjugation of N-(3,5-dichlorophenyl)-2-hydroxysuccinimide (NDHS) followed by hydrolysis. As compared to NDHS, NDHS-O-sulfate is approximately 500-fold more reactive toward GSH conjugation. In rat liver S9, fortifying phase II cofactors (UDPGA or PAPS) in incubation mixtures with NDHS also significantly increased the amount of GSH adducts produced. Results of this research demonstrate that phase II metabolites of NDPS were produced in rats. The formation of the alkyl alcohol-O-glucuronide and O-sulfate conjugates represents bioactivation pathways in the metabolism of NDPS that could potentially contribute to its mechanism of nephrotoxicity.

Diuretic response to cyclophosphamide in rats bearing a matrix metalloproteinase-9-producing tumour

When cyclophosphamide (CY) (100-120 mg kg(-1)) was administered intravenously (i.v.) to normal F-344 rats, oliguria occurred over the 5-day observation period. Conversely, in rats bearing matrix metalloproteinase-9 (MMP-9) producing 13762NF mammary adenocarcinoma (MTLn3 clone), polyuria occurred chiefly during the first 24 h after CY treatment. In parallel with urine volume, a decrease in the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG) was observed during the first 5 days after CY treatment in normal rats, but it increased in MTLn3-bearing rats. No elevation in blood urea nitrogen (BUN) or serum creatinine (Cr) values was observed for either group. Both urine volume and urinary excretion of NAG after CY treatment were lower in rats bearing the MTC clone (lower production of MMP-9) than for those bearing the MTLn3 clone. In the case of treatment with cisplatin (CDDP, 4-6 mg kg(-1)), urine volume, urinary NAG excretion and BUN and serum Cr values all increased in normal rats and were all found to be higher in MTLn3-bearing rats than in normal rats. The diuretic response to these drugs in tumour-bearing (TB) rats may be associated with MMP-9 produced by the tumour cells. This report suggests that the nephrotoxicity due to anti-cancer drugs may change when the drugs are used for the treatment of patients bearing a MMP-9-producing tumour.