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Evaluation of incision wound healing activity of Scorzonera veratrifolia in Wistar albino rats
S158
Abstracts / Toxicology Letters 280S (2017) S157–S159
P-04-08-03 Evaluation of incision wound healing activity of Scorzonera veratrifolia in Wistar albino rats Mert Gecim, Ayfer Beceren, Sezgin Aydemir, Semra Sardas Faculty of Pharmacy, Departments of Pharmaceutical Toxicology, Marmara University, Istanbul, Turkey Scorzonera veratrifolia (S. veratrifolia) is widely used as a natural product in Turkish folk medicine. Studies have shown that Scorzonera species exhibit antioxidant, analgesic, anti-inflammatory and wound healing activity. Up to our knowledge no study in the literature has been demonstrated about the antioxidant activity of Scorzonera species; therefore, the present study was aimed to characterize the potential therapeutic effects of S. veratrifolia in wound model in rats and to determine the possible genotoxic effects. Incisional wound model was applied on rats and the extracts (heptane and methanol extracts) were applied for 10 days. Upon completion of the protocol, animals were decapitated and the skin tissues were removed for determination of malondialdehyde (MDA) and glutathione (GSH) levels and myeloperoxidase (MPO) activity. To assess genotoxicity, the comet assay was applied in peripheral lymphocytes of rats. The level of MDA was increased in untreated incision group (control) (28.37 ± 3.74) compared to methanol (12.99 ± 2.34) and heptan extracts (16.17 ± 2.56), (p < 0.001). Tissue MPO activity was also increased and GSH levels were decreased in the control. Treatment with extracts were reversed these oxidant responses significantly. The alkaline comet assay results are expressed as the mean percentages of DNA in tail (%DNAT ) no significant difference were observed between the all groups. In conclusion, our results demonstrate for the first time that the potential antioxidant and wound healing properties and genotoxic effects of S. veratrifolia in vivo. Further experimental studies are needed to confirm its mechanism in wound healing process. http://dx.doi.org/10.1016/j.toxlet.2017.07.442 P-04-08-04 Treatment with retinoic acid increases severity of 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced skin lesions in hairless mice Stanislav G. Rudyak 1 , Mikhail A. Paltsev 1 , Andrey A. Panteleyev 2 1
Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russian Federation 2 NRC Kurchatov Institute, Moscow, Russian Federation
Exposure to toxic halogenated polyaromatic hydrocarbons, of which dioxin (TCDD) is the most potent, induces multiple symptoms in human skin, inducing chloracne, hyperkeratosis, hamartomas etc. Retinoids are commonly used in therapies of acneiform skin diseases and have been proposed as potential treatment for cutaneous effects of exposure to dioxin-like compounds. While toxic effects of TCDD both in vitro and in vivo have been a subject of multiple studies, effective therapies for their treatment are still absent. We have used hairless (hr) mice and immortalized human keratinocyte cell line (N-TERT) to determine if retinoic acid (RA) can reverse TCDD-induced skin effects. RA suppressed TCDDinduced changes in gene expression and cell viability in N-TERT cells, consistent with the antagonistic action of RA- and TCDDpathways in vitro. In hairless mice, co-treatment with TCDD and RA produced more severe phenotypes, than the ones observed upon treatment with either compound alone. Co-application of TCDD and RA to mouse skin strongly stimulated proliferation of keratinocytes,
resulting in thickening of epidermis and changes in localization of keratinocyte differentiation markers. It has also led to infiltration of cells of immune system in the dermis, and increased expression of inflammation markers, including IL1, and S100 genes. These results demonstrate that RA is ineffective in the treatment of TCDDinduced cutaneous lesions, and suggest that TCDD and RA have synergistic effects on the induction of skin inflammation in hairless mice. Supported by the Russian Science Foundation project 16-1500243. http://dx.doi.org/10.1016/j.toxlet.2017.07.443 P-04-08-05 In-vitro skin corrosivity test of proficiency ® chemicals using Corrositex Assay Manish R. Patel, Ramesh Verma, Manish V. Patel, Vishvesh Dalal, Rajendra Nagane Toxicology, Jai Research Foundation, Vapi, India ®
Corrositex Assay is an in-vitro membrane barrier test method used to identify corrosive chemicals and is an alternative to rabbit skin procedure. Based on the results of qualification screen test, twelve chemicals were found to be suitable for corrositivity system. These chemicals were classified either in Category 1 or Category 2 ® according to the categorisation screen test. Corrositex Assay was performed with negative control (10% citric acid), positive control (sodium hydroxide), CDS (Chemical Detection System) colour control and twelve proficiency chemicals in quadruplicate for maximum four hour according to change in colour in chemical detection system. The mean Corrositex time for the negative and positive control replicates were 71.44 and 11.04 min, respectively, which met the ® acceptance criteria for Corrositex Assay. Time required for change in colour in CDS for nitric acid, phophorus pentachloride and boron trifluoride dehydrate was <3 min, hence classified under “Category 1A”, for Valeryl Chloride, Sodium Hydroxide, 1-(2-Aminoethyl) piperazine was >3–60 min, hence classified under “Category 1B”, for benzenesulfonyl chloride, N,N-dimethyl benzylamine and tetraethylenepentamine was >60–240 min, hence classified under “Category 1C”. Similarly, time required for change in colour in CDS for Eugenol, 4-(methylthio)benzaldehyde and Sodium bicarbonate was >240 min, so were classified under “Non-corrosive”. http://dx.doi.org/10.1016/j.toxlet.2017.07.444
Abstracts / Toxicology Letters 280S (2017) S157–S159
P-04-08-03 Evaluation of incision wound healing activity of Scorzonera veratrifolia in Wistar albino rats Mert Gecim, Ayfer Beceren, Sezgin Aydemir, Semra Sardas Faculty of Pharmacy, Departments of Pharmaceutical Toxicology, Marmara University, Istanbul, Turkey Scorzonera veratrifolia (S. veratrifolia) is widely used as a natural product in Turkish folk medicine. Studies have shown that Scorzonera species exhibit antioxidant, analgesic, anti-inflammatory and wound healing activity. Up to our knowledge no study in the literature has been demonstrated about the antioxidant activity of Scorzonera species; therefore, the present study was aimed to characterize the potential therapeutic effects of S. veratrifolia in wound model in rats and to determine the possible genotoxic effects. Incisional wound model was applied on rats and the extracts (heptane and methanol extracts) were applied for 10 days. Upon completion of the protocol, animals were decapitated and the skin tissues were removed for determination of malondialdehyde (MDA) and glutathione (GSH) levels and myeloperoxidase (MPO) activity. To assess genotoxicity, the comet assay was applied in peripheral lymphocytes of rats. The level of MDA was increased in untreated incision group (control) (28.37 ± 3.74) compared to methanol (12.99 ± 2.34) and heptan extracts (16.17 ± 2.56), (p < 0.001). Tissue MPO activity was also increased and GSH levels were decreased in the control. Treatment with extracts were reversed these oxidant responses significantly. The alkaline comet assay results are expressed as the mean percentages of DNA in tail (%DNAT ) no significant difference were observed between the all groups. In conclusion, our results demonstrate for the first time that the potential antioxidant and wound healing properties and genotoxic effects of S. veratrifolia in vivo. Further experimental studies are needed to confirm its mechanism in wound healing process. http://dx.doi.org/10.1016/j.toxlet.2017.07.442 P-04-08-04 Treatment with retinoic acid increases severity of 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced skin lesions in hairless mice Stanislav G. Rudyak 1 , Mikhail A. Paltsev 1 , Andrey A. Panteleyev 2 1
Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russian Federation 2 NRC Kurchatov Institute, Moscow, Russian Federation
Exposure to toxic halogenated polyaromatic hydrocarbons, of which dioxin (TCDD) is the most potent, induces multiple symptoms in human skin, inducing chloracne, hyperkeratosis, hamartomas etc. Retinoids are commonly used in therapies of acneiform skin diseases and have been proposed as potential treatment for cutaneous effects of exposure to dioxin-like compounds. While toxic effects of TCDD both in vitro and in vivo have been a subject of multiple studies, effective therapies for their treatment are still absent. We have used hairless (hr) mice and immortalized human keratinocyte cell line (N-TERT) to determine if retinoic acid (RA) can reverse TCDD-induced skin effects. RA suppressed TCDDinduced changes in gene expression and cell viability in N-TERT cells, consistent with the antagonistic action of RA- and TCDDpathways in vitro. In hairless mice, co-treatment with TCDD and RA produced more severe phenotypes, than the ones observed upon treatment with either compound alone. Co-application of TCDD and RA to mouse skin strongly stimulated proliferation of keratinocytes,
resulting in thickening of epidermis and changes in localization of keratinocyte differentiation markers. It has also led to infiltration of cells of immune system in the dermis, and increased expression of inflammation markers, including IL1, and S100 genes. These results demonstrate that RA is ineffective in the treatment of TCDDinduced cutaneous lesions, and suggest that TCDD and RA have synergistic effects on the induction of skin inflammation in hairless mice. Supported by the Russian Science Foundation project 16-1500243. http://dx.doi.org/10.1016/j.toxlet.2017.07.443 P-04-08-05 In-vitro skin corrosivity test of proficiency ® chemicals using Corrositex Assay Manish R. Patel, Ramesh Verma, Manish V. Patel, Vishvesh Dalal, Rajendra Nagane Toxicology, Jai Research Foundation, Vapi, India ®
Corrositex Assay is an in-vitro membrane barrier test method used to identify corrosive chemicals and is an alternative to rabbit skin procedure. Based on the results of qualification screen test, twelve chemicals were found to be suitable for corrositivity system. These chemicals were classified either in Category 1 or Category 2 ® according to the categorisation screen test. Corrositex Assay was performed with negative control (10% citric acid), positive control (sodium hydroxide), CDS (Chemical Detection System) colour control and twelve proficiency chemicals in quadruplicate for maximum four hour according to change in colour in chemical detection system. The mean Corrositex time for the negative and positive control replicates were 71.44 and 11.04 min, respectively, which met the ® acceptance criteria for Corrositex Assay. Time required for change in colour in CDS for nitric acid, phophorus pentachloride and boron trifluoride dehydrate was <3 min, hence classified under “Category 1A”, for Valeryl Chloride, Sodium Hydroxide, 1-(2-Aminoethyl) piperazine was >3–60 min, hence classified under “Category 1B”, for benzenesulfonyl chloride, N,N-dimethyl benzylamine and tetraethylenepentamine was >60–240 min, hence classified under “Category 1C”. Similarly, time required for change in colour in CDS for Eugenol, 4-(methylthio)benzaldehyde and Sodium bicarbonate was >240 min, so were classified under “Non-corrosive”. http://dx.doi.org/10.1016/j.toxlet.2017.07.444