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Opposite Expression of SPARC between the Liver and Pancreas in Streptozotocin-Induced Diabetic Rats.

Aseer KR, Kim SW, Choi MS, Yun JW - PLoS ONE (2015)

Bottom Line: Diabetic liver showed significant up-regulation of Tgfb1 as well as moderately less up-regulated TNFα and reduced Fn1, resulting in elevated fibrogenesis.PARP-1 was not up-regulated during CD95-mediated apoptosis, resulting in restoration of high ATP levels in the diabetic liver.High and low cellular insulin content was found in the diabetic liver and pancreas, respectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology, Daegu University, Kyungsan, Kyungbuk, 712-714, Republic of Korea.

ABSTRACT
Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein that regulates several cellular events, including inflammation and tissue remodelling. In this study, we investigated the tissue-specific expression of SPARC in streptozotocin (STZ)-induced diabetes, and found that SPARC was significantly up-regulated in the liver while down-regulated in the pancreas of STZ-induced diabetic rats. Chronic inflammation occurred in the diabetic pancreas accompanied by up-regulation of CCAAT/enhancer-binding protein beta (C/EBPβ) and its targets (TNFα, Il6, CRP, and Fn1) as well as myeloperoxidase (Mpo) and C-X-C chemokine receptor type 2 (Cxcr2). Diabetic liver showed significant up-regulation of Tgfb1 as well as moderately less up-regulated TNFα and reduced Fn1, resulting in elevated fibrogenesis. PARP-1 was not up-regulated during CD95-mediated apoptosis, resulting in restoration of high ATP levels in the diabetic liver. On the contrary, CD95-dependent apoptosis was not observed in the diabetic pancreas due to up-regulation of PARP-1 and ATP depletion, resulting in necrosis. The cytoprotective machinery was damaged by pancreatic inflammation, whereas adequate antioxidant capacity indicates low oxidative stress in the diabetic liver. High and low cellular insulin content was found in the diabetic liver and pancreas, respectively. Furthermore, we identified six novel interacting partner proteins of SPARC by co-immunoprecipitation in the diabetic liver and pancreas, and their interactions with SPARC were predicted by bioinformatics tools. Taken together, opposite expression of SPARC in the diabetic liver and pancreas may be related to inflammation and immune cell infiltration, degrees of apoptosis and fibrosis, cytoprotective machinery, and cellular insulin levels.

No MeSH data available.


Related in: MedlinePlus

Immunohistochemistry of SPARC-interacting partner proteins (CA3, CPS1, RARhoGAP, and BHMT) in liver (A) as well as PA and APC2 in pancreatic tissue (B) from control and diabetic rats.Representative photomicrographs are shown from sections counter-stained with haematoxylin (magnification X400 and scale bar represents 50 μm).
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pone.0131189.g007: Immunohistochemistry of SPARC-interacting partner proteins (CA3, CPS1, RARhoGAP, and BHMT) in liver (A) as well as PA and APC2 in pancreatic tissue (B) from control and diabetic rats.Representative photomicrographs are shown from sections counter-stained with haematoxylin (magnification X400 and scale bar represents 50 μm).

Mentions: We also performed Co-IP in order to isolate the interacting protein complexes of SPARC in the liver and pancreas. As shown in Fig 6A, PMF analysis revealed four novel interacting partners in the liver, including carbonic anhydrase 3 (CA3), carbamoyl-phosphate synthase (CPS1), Rho GTPase-activating protein 20 (RARhoGAP), and betaine-homocysteine S-methyl transferase (BHMT). Likewise, two novel SPARC-interacting partners were identified in the pancreas, including pancreatic alpha amylase (PA) and adenomatous polyposis coli protein (APC2) (Fig 6B). STRING network analysis predicted a direct association of SPARC/Sparc and CA3/Car3, which in turn proceeds through the series of interactions with BHMT/Bhmt, and CPS1/Cps1 (Fig 6C) in the liver, whereas SPARC was indirectly interconnected with RARhoGAP/Arhgap20. STRING analysis also showed that SPARC/ Sparc interacted directly with APC2/Apc2 in the pancreas as well as indirectly with PA/Amy2 through intermediates (Fig 6D). Immunoblot analysis was performed for the identified SPARC-interacting protein partners, and found that CPS1, RARhoGAP, and BHMT were up-regulated while CA3 was down-regulated in the diabetic liver (Fig 6E). Meanwhile, APC2 expression was highly induced, whereas PA levels sharply declined in the diabetic pancreas (Fig 6F). Immunohistochemical analyses confirmed these immunoblot results by showing highly augmented immunoreactivity of CPS1, RARhoGAP, and BHMT in the diabetic liver (Fig 7A) as well as APC2 in the diabetic pancreas (Fig 7B). In contrast, CA3 and PA proteins showed less immunoreactivity in the diabetic liver and acinar region of the diabetic pancreas, respectively, as in the immunoblot results (Fig 7A and 7B).


Opposite Expression of SPARC between the Liver and Pancreas in Streptozotocin-Induced Diabetic Rats.

Aseer KR, Kim SW, Choi MS, Yun JW - PLoS ONE (2015)

Immunohistochemistry of SPARC-interacting partner proteins (CA3, CPS1, RARhoGAP, and BHMT) in liver (A) as well as PA and APC2 in pancreatic tissue (B) from control and diabetic rats.Representative photomicrographs are shown from sections counter-stained with haematoxylin (magnification X400 and scale bar represents 50 μm).
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4481468&req=5

pone.0131189.g007: Immunohistochemistry of SPARC-interacting partner proteins (CA3, CPS1, RARhoGAP, and BHMT) in liver (A) as well as PA and APC2 in pancreatic tissue (B) from control and diabetic rats.Representative photomicrographs are shown from sections counter-stained with haematoxylin (magnification X400 and scale bar represents 50 μm).
Mentions: We also performed Co-IP in order to isolate the interacting protein complexes of SPARC in the liver and pancreas. As shown in Fig 6A, PMF analysis revealed four novel interacting partners in the liver, including carbonic anhydrase 3 (CA3), carbamoyl-phosphate synthase (CPS1), Rho GTPase-activating protein 20 (RARhoGAP), and betaine-homocysteine S-methyl transferase (BHMT). Likewise, two novel SPARC-interacting partners were identified in the pancreas, including pancreatic alpha amylase (PA) and adenomatous polyposis coli protein (APC2) (Fig 6B). STRING network analysis predicted a direct association of SPARC/Sparc and CA3/Car3, which in turn proceeds through the series of interactions with BHMT/Bhmt, and CPS1/Cps1 (Fig 6C) in the liver, whereas SPARC was indirectly interconnected with RARhoGAP/Arhgap20. STRING analysis also showed that SPARC/ Sparc interacted directly with APC2/Apc2 in the pancreas as well as indirectly with PA/Amy2 through intermediates (Fig 6D). Immunoblot analysis was performed for the identified SPARC-interacting protein partners, and found that CPS1, RARhoGAP, and BHMT were up-regulated while CA3 was down-regulated in the diabetic liver (Fig 6E). Meanwhile, APC2 expression was highly induced, whereas PA levels sharply declined in the diabetic pancreas (Fig 6F). Immunohistochemical analyses confirmed these immunoblot results by showing highly augmented immunoreactivity of CPS1, RARhoGAP, and BHMT in the diabetic liver (Fig 7A) as well as APC2 in the diabetic pancreas (Fig 7B). In contrast, CA3 and PA proteins showed less immunoreactivity in the diabetic liver and acinar region of the diabetic pancreas, respectively, as in the immunoblot results (Fig 7A and 7B).

Bottom Line: Diabetic liver showed significant up-regulation of Tgfb1 as well as moderately less up-regulated TNFα and reduced Fn1, resulting in elevated fibrogenesis.PARP-1 was not up-regulated during CD95-mediated apoptosis, resulting in restoration of high ATP levels in the diabetic liver.High and low cellular insulin content was found in the diabetic liver and pancreas, respectively.

View Article: PubMed Central - PubMed

Affiliation: Department of Biotechnology, Daegu University, Kyungsan, Kyungbuk, 712-714, Republic of Korea.

ABSTRACT
Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein that regulates several cellular events, including inflammation and tissue remodelling. In this study, we investigated the tissue-specific expression of SPARC in streptozotocin (STZ)-induced diabetes, and found that SPARC was significantly up-regulated in the liver while down-regulated in the pancreas of STZ-induced diabetic rats. Chronic inflammation occurred in the diabetic pancreas accompanied by up-regulation of CCAAT/enhancer-binding protein beta (C/EBPβ) and its targets (TNFα, Il6, CRP, and Fn1) as well as myeloperoxidase (Mpo) and C-X-C chemokine receptor type 2 (Cxcr2). Diabetic liver showed significant up-regulation of Tgfb1 as well as moderately less up-regulated TNFα and reduced Fn1, resulting in elevated fibrogenesis. PARP-1 was not up-regulated during CD95-mediated apoptosis, resulting in restoration of high ATP levels in the diabetic liver. On the contrary, CD95-dependent apoptosis was not observed in the diabetic pancreas due to up-regulation of PARP-1 and ATP depletion, resulting in necrosis. The cytoprotective machinery was damaged by pancreatic inflammation, whereas adequate antioxidant capacity indicates low oxidative stress in the diabetic liver. High and low cellular insulin content was found in the diabetic liver and pancreas, respectively. Furthermore, we identified six novel interacting partner proteins of SPARC by co-immunoprecipitation in the diabetic liver and pancreas, and their interactions with SPARC were predicted by bioinformatics tools. Taken together, opposite expression of SPARC in the diabetic liver and pancreas may be related to inflammation and immune cell infiltration, degrees of apoptosis and fibrosis, cytoprotective machinery, and cellular insulin levels.

No MeSH data available.


Related in: MedlinePlus