- Email: [email protected]
Calcium ameliorates gentamicin-induced glomerular basement membrane changes in rats
S74
Abstracts / Toxicology Letters 211S (2012) S43–S216
of acetaminophen (2 g/kg, p.o.). Plant extract (PB) and its active principle (TA) were given at the dose of 100 mg/kg and 25 mg/kg, respectively (p.o.) after 24 h of toxicant administration. Results: The hepatotoxicity produced by acute paracetamol administration was found to be inhibited by Polygonum bistorta and tannic acid with evidence of decreased levels of serum transaminases, alkaline phosphatase, protein, albumin, bilirubin, urea, creatinine, triglycerides and cholesterol concentration whereas increase was found in blood sugar. A significant rise was observed in lipid peroxidation level however reduced glutathione content was decreased. A concomitant fall was observed in the enzymatic activities of adenosine triphosphatase, glucose-6-phosphatase and histopathological findings. Plant extract and its active principle prevent the development of acute liver damage, thus supported these biochemical and histopathological findings. Conclusion: The results of this study clearly indicate that PB and TA have a potent hepatoprotective action; whereas tannic acid showed protective effect compared to Polygonum bistorta against acetaminophen-induced toxicological profile. doi:10.1016/j.toxlet.2012.03.285
P10-02 Calcium ameliorates gentamicin-induced glomerular basement membrane changes in rats Nenad Stojiljkovic 1 , Milan Stoiljkovic 2 , Sonja Ilic 3 , Marija Gocmanac-Ignjatovic 3 University of Nis School of Medicine, Serbia, 2 Dept. of Pharmacology, Serbia, 3 Dept. of Physiology, Serbia
1
Wider use of gentamicin (GM) is limited by its nephrotoxic effects which lead to acute kidney injury. The aim of this study was to test whether calcium supplementation has protective effect on gentamicin-induced glomerular basement membrane (GBM) alterations in rats. Experiments were done on 24 adult Wistar male rats divided into three groups of 8 animals each. GM-group received gentamicin intraperitoneally in dose of 100 mg/kg, GMCa-group received same dose of gentamicin concomitantly with 1 g/kg calciumcarbonate given orally, while control or C-group, received 1 ml of saline daily. All groups were treated during 8 consecutive days. Quantitative evaluation of gentamicin-induced morphological and functional kidney changes was performed by histopathological (Jones methenamine silver), morphometrical (GBM thickness) and biochemical analyses. Compared to control GM-group rats had diffusely and unequally thickened GBM with neutrophil cells infiltration and coagulationtype necrosis along with cytoplasm vacuolation of proximal tubules. This was reduced in GMCa-group of rats although their glomeruli were somewhat enlarged. In this group GBM was only segmentally thickened but without signs of necrosis. Morphometric analyses showed significantly greater thickness of GBM in GM-group than in GMCa and C groups (p < 0.001). Contrary, no significant differences were observed between GMCa and control animals. Biochemical analysis showed significantly elevation of blood urea and serum creatinine concentration in GM-group compared to other groups (p < 0.01). Calcium supplementation during treatment with gentamicin significantly reduced morphological and functional kidney tissue and particularly GBM alterations suggesting its protective effects possibly by inhibition of gentamicin uptake and accumulation in renal cell liposomes. doi:10.1016/j.toxlet.2012.03.286
P10-03 The use of the minipig in nonclinical safety studies in the pharmaceutical industry Alli Manninen, Bo Blomgren, Janet Hoogstraate AstraZeneca R&D Södertälje, Sweden Purpose: This abstract presents the use of the minipig as a species for general toxicity studies supporting chronic oral administration of drug substances in humans, in this instance for chronic pain. The default species would have been the dog, but the minipig was instead selected, since the pharmacokinetic profile of the compound/main metabolite in the minipig was similar to that in man. The challenge when using the minipig was that pharmacology driven gastrointestinal adverse effects were expected. Knowing that the minipig is sensitive to stress during long-term studies, any background findings in the controls might not differ substantially from effects caused by treatment. Method: Toxicity studies using oral, once-daily gavage were performed with this test compound. Studies using minipigs (Göttingen) were initiated by MTD and 7 day dose finding studies, followed by studies of up to 12 months’ duration. The number of animals per group (including a control) in the pivotal studies was at least 3 of each sex. The endpoints were clinical observations, body weight, food consumption, ophthalmoscopy, electrocardiography, clinical pathology, macroscopic and microscopic pathology and toxicokinetic evaluation. Results and conclusions: Macroscopic and microscopic pathology revealed background findings of minimal to slight levels of stomach erosions and/or ulceration and minor changes in the small intestine in the control group, but the distinction between these findings and the pharmacology driven effects in the compound-treated animals was very clear. The long-term general toxicity studies showed that the minipig is a suitable species for toxicity testing of drugs intended for chronic use in humans. doi:10.1016/j.toxlet.2012.03.287
P10-04 Embryo toxicity of all-trans-retinoic acid in human embryonic stem cells Smita Jagtap, Kesavan Meganathan, Vilas Wagh, John Antonydas Gaspar, Jürgen Hescheler, Agapios Sachinidis University of Cologne, Germany Background: The gene expression profiling of human embryonic stem cells (hESC) under the exposure to reference toxicants may contribute to identify potential sensitive biomarkers relevant for human toxicity. Small molecules tested on monolayer pluripotent hESC and analyzed for self renewal and differentiation leading to the identification of compounds that may promote short term maintenance and directing early lineage selection during differentiation. Methods: To profile the effect of the embryotoxicant, all trans retinoic acid (AtRA) was treated on hESC at a concentration of 5 M, in the presence and absence of bFGF. Affymetrix microarray performed to generate toxicogenomic gene signatures. Additionally, mechanistic analysis using Immunostaining, Immunoblotting and RT-qPCR was performed. Results and conclusion: We demonstrate that AtRA inactivates WNT signaling even in the presence of exogenous bFGF that promotes maintenance of the pluripotent state, thereby resulting in the loss of hESC pluripotency and induction of trophoblast differentiation. We also show that BMP4 was upregulated and AtRA was able to modulate the TGF b signaling
Abstracts / Toxicology Letters 211S (2012) S43–S216
of acetaminophen (2 g/kg, p.o.). Plant extract (PB) and its active principle (TA) were given at the dose of 100 mg/kg and 25 mg/kg, respectively (p.o.) after 24 h of toxicant administration. Results: The hepatotoxicity produced by acute paracetamol administration was found to be inhibited by Polygonum bistorta and tannic acid with evidence of decreased levels of serum transaminases, alkaline phosphatase, protein, albumin, bilirubin, urea, creatinine, triglycerides and cholesterol concentration whereas increase was found in blood sugar. A significant rise was observed in lipid peroxidation level however reduced glutathione content was decreased. A concomitant fall was observed in the enzymatic activities of adenosine triphosphatase, glucose-6-phosphatase and histopathological findings. Plant extract and its active principle prevent the development of acute liver damage, thus supported these biochemical and histopathological findings. Conclusion: The results of this study clearly indicate that PB and TA have a potent hepatoprotective action; whereas tannic acid showed protective effect compared to Polygonum bistorta against acetaminophen-induced toxicological profile. doi:10.1016/j.toxlet.2012.03.285
P10-02 Calcium ameliorates gentamicin-induced glomerular basement membrane changes in rats Nenad Stojiljkovic 1 , Milan Stoiljkovic 2 , Sonja Ilic 3 , Marija Gocmanac-Ignjatovic 3 University of Nis School of Medicine, Serbia, 2 Dept. of Pharmacology, Serbia, 3 Dept. of Physiology, Serbia
1
Wider use of gentamicin (GM) is limited by its nephrotoxic effects which lead to acute kidney injury. The aim of this study was to test whether calcium supplementation has protective effect on gentamicin-induced glomerular basement membrane (GBM) alterations in rats. Experiments were done on 24 adult Wistar male rats divided into three groups of 8 animals each. GM-group received gentamicin intraperitoneally in dose of 100 mg/kg, GMCa-group received same dose of gentamicin concomitantly with 1 g/kg calciumcarbonate given orally, while control or C-group, received 1 ml of saline daily. All groups were treated during 8 consecutive days. Quantitative evaluation of gentamicin-induced morphological and functional kidney changes was performed by histopathological (Jones methenamine silver), morphometrical (GBM thickness) and biochemical analyses. Compared to control GM-group rats had diffusely and unequally thickened GBM with neutrophil cells infiltration and coagulationtype necrosis along with cytoplasm vacuolation of proximal tubules. This was reduced in GMCa-group of rats although their glomeruli were somewhat enlarged. In this group GBM was only segmentally thickened but without signs of necrosis. Morphometric analyses showed significantly greater thickness of GBM in GM-group than in GMCa and C groups (p < 0.001). Contrary, no significant differences were observed between GMCa and control animals. Biochemical analysis showed significantly elevation of blood urea and serum creatinine concentration in GM-group compared to other groups (p < 0.01). Calcium supplementation during treatment with gentamicin significantly reduced morphological and functional kidney tissue and particularly GBM alterations suggesting its protective effects possibly by inhibition of gentamicin uptake and accumulation in renal cell liposomes. doi:10.1016/j.toxlet.2012.03.286
P10-03 The use of the minipig in nonclinical safety studies in the pharmaceutical industry Alli Manninen, Bo Blomgren, Janet Hoogstraate AstraZeneca R&D Södertälje, Sweden Purpose: This abstract presents the use of the minipig as a species for general toxicity studies supporting chronic oral administration of drug substances in humans, in this instance for chronic pain. The default species would have been the dog, but the minipig was instead selected, since the pharmacokinetic profile of the compound/main metabolite in the minipig was similar to that in man. The challenge when using the minipig was that pharmacology driven gastrointestinal adverse effects were expected. Knowing that the minipig is sensitive to stress during long-term studies, any background findings in the controls might not differ substantially from effects caused by treatment. Method: Toxicity studies using oral, once-daily gavage were performed with this test compound. Studies using minipigs (Göttingen) were initiated by MTD and 7 day dose finding studies, followed by studies of up to 12 months’ duration. The number of animals per group (including a control) in the pivotal studies was at least 3 of each sex. The endpoints were clinical observations, body weight, food consumption, ophthalmoscopy, electrocardiography, clinical pathology, macroscopic and microscopic pathology and toxicokinetic evaluation. Results and conclusions: Macroscopic and microscopic pathology revealed background findings of minimal to slight levels of stomach erosions and/or ulceration and minor changes in the small intestine in the control group, but the distinction between these findings and the pharmacology driven effects in the compound-treated animals was very clear. The long-term general toxicity studies showed that the minipig is a suitable species for toxicity testing of drugs intended for chronic use in humans. doi:10.1016/j.toxlet.2012.03.287
P10-04 Embryo toxicity of all-trans-retinoic acid in human embryonic stem cells Smita Jagtap, Kesavan Meganathan, Vilas Wagh, John Antonydas Gaspar, Jürgen Hescheler, Agapios Sachinidis University of Cologne, Germany Background: The gene expression profiling of human embryonic stem cells (hESC) under the exposure to reference toxicants may contribute to identify potential sensitive biomarkers relevant for human toxicity. Small molecules tested on monolayer pluripotent hESC and analyzed for self renewal and differentiation leading to the identification of compounds that may promote short term maintenance and directing early lineage selection during differentiation. Methods: To profile the effect of the embryotoxicant, all trans retinoic acid (AtRA) was treated on hESC at a concentration of 5 M, in the presence and absence of bFGF. Affymetrix microarray performed to generate toxicogenomic gene signatures. Additionally, mechanistic analysis using Immunostaining, Immunoblotting and RT-qPCR was performed. Results and conclusion: We demonstrate that AtRA inactivates WNT signaling even in the presence of exogenous bFGF that promotes maintenance of the pluripotent state, thereby resulting in the loss of hESC pluripotency and induction of trophoblast differentiation. We also show that BMP4 was upregulated and AtRA was able to modulate the TGF b signaling