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Lack of the matricellular protein SPARC (secreted protein, acidic and rich in cysteine) attenuates liver fibrogenesis in mice.

Atorrasagasti C, Peixoto E, Aquino JB, Kippes N, Malvicini M, Alaniz L, Garcia M, Piccioni F, Fiore EJ, Bayo J, Bataller R, Guruceaga E, Corrales F, Podhajcer O, Mazzolini G - PLoS ONE (2013)

Bottom Line: Consistently, collagen deposits and mRNA expression levels were decreased in SPARC(-/-) mice when compared to SPARC(+/+) mice; in addition, MMP-2 expression was increased in SPARC(-/-) mice.A reduction in the number of activated myofibroblasts was observed.Overall our data suggest that SPARC plays a significant role in liver fibrogenesis.

View Article: PubMed Central - PubMed

Affiliation: Gene Therapy Laboratory, School of Medicine, Austral University, Derqui-Pilar, Buenos Aires, Argentina.

ABSTRACT

Introduction: Secreted Protein, Acidic and Rich in Cysteine (SPARC) is a matricellular protein involved in many biological processes and found over-expressed in cirrhotic livers. By mean of a genetic approach we herein provide evidence from different in vivo liver disease models suggesting a profibrogenic role for SPARC.

Methods: Two in vivo models of liver fibrosis, based on TAA administration and bile duct ligation, were developed on SPARC wild-type (SPARC(+/+)) and knock-out (SPARC(-/-)) mice. Hepatic SPARC expression was analyzed by qPCR. Fibrosis was assessed by Sirius Red staining, and the maturation state of collagen fibers was analyzed using polarized light. Necroinflammatory activity was evaluated by applying the Knodell score and liver inflammatory infiltration was characterized by immunohistochemistry. Hepatic stellate cell activation was assessed by α-SMA immunohistochemistry. In addition, pro-fibrogenic genes and inflammatory cytokines were measured by qPCR and/or ELISA. Liver gene expression profile was analyzed in SPARC(-/-) and SPARC(+/+) mice using Affymetrix Mouse Gene ST 1.0 array.

Results: SPARC expression was found induced in fibrotic livers of mouse and human. SPARC(-/-) mice showed a reduction in the degree of inflammation, mainly CD4+ cells, and fibrosis. Consistently, collagen deposits and mRNA expression levels were decreased in SPARC(-/-) mice when compared to SPARC(+/+) mice; in addition, MMP-2 expression was increased in SPARC(-/-) mice. A reduction in the number of activated myofibroblasts was observed. Moreover, TGF-β1 expression levels were down-regulated in the liver as well as in the serum of TAA-treated knock-out animals. Ingenuity Pathway Analysis (IPA) analysis suggested several gene networks which might involve protective mechanisms of SPARC deficiency against liver fibrogenesis and a better established machinery to repair DNA and detoxify from external chemical stimuli.

Conclusions: Overall our data suggest that SPARC plays a significant role in liver fibrogenesis. Interventions to inhibit SPARC expression are suggested as promising approaches for liver fibrosis treatment.

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Reduced liver damage in SPARC deficient mice.(A–F) Representative photomicrographs of liver sections from untreated SPARC+/+ (A) or 10 weeks TAA-treated SPARC+/+ or SPARC−/− mice (n  = 6–8), stained with H&E (A–C) or Masson’s trichrome (D–F). (G–J) Representative photomicrographs of liver sections from SPARC+/+ and SPARC−/− mice subjected to BDL, stained with H&E (G–H) or Masson’s trichrome (I–J). Original magnification 200X. PT, portal tract; CV, central vein. (K) Serum ALT and AST levels were measured at the indicated time in TAA-treated and BDL mice. Dotted lines, upper normal limited. **p<0.05 versus treated SPARC+/+.
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pone-0054962-g003: Reduced liver damage in SPARC deficient mice.(A–F) Representative photomicrographs of liver sections from untreated SPARC+/+ (A) or 10 weeks TAA-treated SPARC+/+ or SPARC−/− mice (n  = 6–8), stained with H&E (A–C) or Masson’s trichrome (D–F). (G–J) Representative photomicrographs of liver sections from SPARC+/+ and SPARC−/− mice subjected to BDL, stained with H&E (G–H) or Masson’s trichrome (I–J). Original magnification 200X. PT, portal tract; CV, central vein. (K) Serum ALT and AST levels were measured at the indicated time in TAA-treated and BDL mice. Dotted lines, upper normal limited. **p<0.05 versus treated SPARC+/+.

Mentions: We next decided to investigate whether SPARC deficiency may influence liver fibrogenesis and processes therein involved. With this aim, two types of liver fibrosis in vivo models were applied to SPARC−/− and in SPARC+/+ mice: chronic TAA application and bile duct ligation. After 10 weeks of TAA administration, SPARC+/+ livers showed extensive appearance of portal-portal and central-portal fibrous septae, regenerative nodules, and distortion of liver architecture (Figures 3). However, a marked reduction in the amount of fibrous septae and of regenerative nodules was found in TAA-treated SPARC−/− animals (Figure 3A–F). Similar results were observed in animals subjected to BDL at 7 days post-surgery: while SPARC+/+ mice developed prominent fibrous expansions in periportal areas, they were almost absent in SPARC−/− animals (Figure 3G–J).


Lack of the matricellular protein SPARC (secreted protein, acidic and rich in cysteine) attenuates liver fibrogenesis in mice.

Atorrasagasti C, Peixoto E, Aquino JB, Kippes N, Malvicini M, Alaniz L, Garcia M, Piccioni F, Fiore EJ, Bayo J, Bataller R, Guruceaga E, Corrales F, Podhajcer O, Mazzolini G - PLoS ONE (2013)

Reduced liver damage in SPARC deficient mice.(A–F) Representative photomicrographs of liver sections from untreated SPARC+/+ (A) or 10 weeks TAA-treated SPARC+/+ or SPARC−/− mice (n  = 6–8), stained with H&E (A–C) or Masson’s trichrome (D–F). (G–J) Representative photomicrographs of liver sections from SPARC+/+ and SPARC−/− mice subjected to BDL, stained with H&E (G–H) or Masson’s trichrome (I–J). Original magnification 200X. PT, portal tract; CV, central vein. (K) Serum ALT and AST levels were measured at the indicated time in TAA-treated and BDL mice. Dotted lines, upper normal limited. **p<0.05 versus treated SPARC+/+.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3569438&req=5

pone-0054962-g003: Reduced liver damage in SPARC deficient mice.(A–F) Representative photomicrographs of liver sections from untreated SPARC+/+ (A) or 10 weeks TAA-treated SPARC+/+ or SPARC−/− mice (n  = 6–8), stained with H&E (A–C) or Masson’s trichrome (D–F). (G–J) Representative photomicrographs of liver sections from SPARC+/+ and SPARC−/− mice subjected to BDL, stained with H&E (G–H) or Masson’s trichrome (I–J). Original magnification 200X. PT, portal tract; CV, central vein. (K) Serum ALT and AST levels were measured at the indicated time in TAA-treated and BDL mice. Dotted lines, upper normal limited. **p<0.05 versus treated SPARC+/+.
Mentions: We next decided to investigate whether SPARC deficiency may influence liver fibrogenesis and processes therein involved. With this aim, two types of liver fibrosis in vivo models were applied to SPARC−/− and in SPARC+/+ mice: chronic TAA application and bile duct ligation. After 10 weeks of TAA administration, SPARC+/+ livers showed extensive appearance of portal-portal and central-portal fibrous septae, regenerative nodules, and distortion of liver architecture (Figures 3). However, a marked reduction in the amount of fibrous septae and of regenerative nodules was found in TAA-treated SPARC−/− animals (Figure 3A–F). Similar results were observed in animals subjected to BDL at 7 days post-surgery: while SPARC+/+ mice developed prominent fibrous expansions in periportal areas, they were almost absent in SPARC−/− animals (Figure 3G–J).

Bottom Line: Consistently, collagen deposits and mRNA expression levels were decreased in SPARC(-/-) mice when compared to SPARC(+/+) mice; in addition, MMP-2 expression was increased in SPARC(-/-) mice.A reduction in the number of activated myofibroblasts was observed.Overall our data suggest that SPARC plays a significant role in liver fibrogenesis.

View Article: PubMed Central - PubMed

Affiliation: Gene Therapy Laboratory, School of Medicine, Austral University, Derqui-Pilar, Buenos Aires, Argentina.

ABSTRACT

Introduction: Secreted Protein, Acidic and Rich in Cysteine (SPARC) is a matricellular protein involved in many biological processes and found over-expressed in cirrhotic livers. By mean of a genetic approach we herein provide evidence from different in vivo liver disease models suggesting a profibrogenic role for SPARC.

Methods: Two in vivo models of liver fibrosis, based on TAA administration and bile duct ligation, were developed on SPARC wild-type (SPARC(+/+)) and knock-out (SPARC(-/-)) mice. Hepatic SPARC expression was analyzed by qPCR. Fibrosis was assessed by Sirius Red staining, and the maturation state of collagen fibers was analyzed using polarized light. Necroinflammatory activity was evaluated by applying the Knodell score and liver inflammatory infiltration was characterized by immunohistochemistry. Hepatic stellate cell activation was assessed by α-SMA immunohistochemistry. In addition, pro-fibrogenic genes and inflammatory cytokines were measured by qPCR and/or ELISA. Liver gene expression profile was analyzed in SPARC(-/-) and SPARC(+/+) mice using Affymetrix Mouse Gene ST 1.0 array.

Results: SPARC expression was found induced in fibrotic livers of mouse and human. SPARC(-/-) mice showed a reduction in the degree of inflammation, mainly CD4+ cells, and fibrosis. Consistently, collagen deposits and mRNA expression levels were decreased in SPARC(-/-) mice when compared to SPARC(+/+) mice; in addition, MMP-2 expression was increased in SPARC(-/-) mice. A reduction in the number of activated myofibroblasts was observed. Moreover, TGF-β1 expression levels were down-regulated in the liver as well as in the serum of TAA-treated knock-out animals. Ingenuity Pathway Analysis (IPA) analysis suggested several gene networks which might involve protective mechanisms of SPARC deficiency against liver fibrogenesis and a better established machinery to repair DNA and detoxify from external chemical stimuli.

Conclusions: Overall our data suggest that SPARC plays a significant role in liver fibrogenesis. Interventions to inhibit SPARC expression are suggested as promising approaches for liver fibrosis treatment.

Show MeSH
Related in: MedlinePlus