Hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice.
The induction of heat shock proteins (HSP) protects isolated islet cells against the cytotoxicity of inflammatory mediators in vitro. Very little information is available about the effect of HSP overexpression on function of preconditioned islet grafts. The present study investigated the function of...
| Main Authors: | , , , , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
2003
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| _version_ | 1826282731038834688 |
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| author | Brandhorst, D Brandhorst, H Kumarasamy, V Maataoui, A Alt, A Brendel, MD Bretzel, R |
| author_facet | Brandhorst, D Brandhorst, H Kumarasamy, V Maataoui, A Alt, A Brendel, MD Bretzel, R |
| author_sort | Brandhorst, D |
| collection | OXFORD |
| description | The induction of heat shock proteins (HSP) protects isolated islet cells against the cytotoxicity of inflammatory mediators in vitro. Very little information is available about the effect of HSP overexpression on function of preconditioned islet grafts. The present study investigated the function of heat-exposed pig islets after transplantation into immunocompetent mice in comparison with in vitro resistance against inflammatory mediators. Pig islets were preconditioned at 43 degrees C or sham treated prior to subcapsular transplantation into diabetic C57/Bl6j mice. Nondiabetic mice simultaneously receiving preconditioned and control islets were subjected to bilateral nephrectomy for determination of pig insulin. Resistance against H2O2, NO, human Il-1beta, IFN-gamma, or TNF-alpha was assessed by trypan blue exclusion and insulin determination. Heat-induced protein expression was confirmed by Western blot analysis. Graft preconditioning increased resistance against H2O2, NO, or cytokines (p < 0.05) but decreased survival in nondiabetic mice (p < 0.05) and function in diabetic mice (p < 0.01). Upregulation of caspase-3 activity as well as Bax, Fas, FasL, and DFF expression (p < 0.05) indicated simultaneous induction of apoptosis. The coexpression of HSP and proapoptotic proteins reveals the dual character of the stress response simultaneously starting mechanisms for protection and apoptosis. In vitro assays seem to reflect only insufficiently the situation of islets after transplantation. |
| first_indexed | 2024-03-07T00:48:16Z |
| format | Journal article |
| id | oxford-uuid:85712d1f-c1d6-48bc-8ce1-394179cedb3e |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T00:48:16Z |
| publishDate | 2003 |
| record_format | dspace |
| spelling | oxford-uuid:85712d1f-c1d6-48bc-8ce1-394179cedb3e2022-03-26T21:57:40ZHyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:85712d1f-c1d6-48bc-8ce1-394179cedb3eEnglishSymplectic Elements at Oxford2003Brandhorst, DBrandhorst, HKumarasamy, VMaataoui, AAlt, ABrendel, MDBretzel, RThe induction of heat shock proteins (HSP) protects isolated islet cells against the cytotoxicity of inflammatory mediators in vitro. Very little information is available about the effect of HSP overexpression on function of preconditioned islet grafts. The present study investigated the function of heat-exposed pig islets after transplantation into immunocompetent mice in comparison with in vitro resistance against inflammatory mediators. Pig islets were preconditioned at 43 degrees C or sham treated prior to subcapsular transplantation into diabetic C57/Bl6j mice. Nondiabetic mice simultaneously receiving preconditioned and control islets were subjected to bilateral nephrectomy for determination of pig insulin. Resistance against H2O2, NO, human Il-1beta, IFN-gamma, or TNF-alpha was assessed by trypan blue exclusion and insulin determination. Heat-induced protein expression was confirmed by Western blot analysis. Graft preconditioning increased resistance against H2O2, NO, or cytokines (p < 0.05) but decreased survival in nondiabetic mice (p < 0.05) and function in diabetic mice (p < 0.01). Upregulation of caspase-3 activity as well as Bax, Fas, FasL, and DFF expression (p < 0.05) indicated simultaneous induction of apoptosis. The coexpression of HSP and proapoptotic proteins reveals the dual character of the stress response simultaneously starting mechanisms for protection and apoptosis. In vitro assays seem to reflect only insufficiently the situation of islets after transplantation. |
| spellingShingle | Brandhorst, D Brandhorst, H Kumarasamy, V Maataoui, A Alt, A Brendel, MD Bretzel, R Hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice. |
| title | Hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice. |
| title_full | Hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice. |
| title_fullStr | Hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice. |
| title_full_unstemmed | Hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice. |
| title_short | Hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice. |
| title_sort | hyperthermic preconditioning protects pig islet grafts from early inflammation but enhances rejection in immunocompetent mice |
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