Dataset Information

Quantitative evaluation of hepatic integrin ?_v?₃ expression by positron emission tomography imaging using ¹⁸F-FPP-RGD₂ in rats with non-alcoholic steatohepatitis.

ABSTRACT:

Background

Integrin ?_v?₃, which are expressed by activated hepatic stellate cells in non-alcoholic steatohepatitis (NASH), play an important role in the fibrosis. Recently, we reported that an RGD peptide positron emission tomography (PET) probe is useful as a predictor of hepatic fibrosis. Kinetic analysis of the RGD PET probe has been performed in tumours, but not in hepatic fibrosis. Therefore, we aimed to quantify hepatic integrin ?_v?₃ in a model of NASH by kinetic analysis using ¹⁸F-FPP-RGD₂, an integrin ?_v?₃ PET probe.

Methods

¹⁸F-FPP-RGD₂ PET/CT scans were performed in control and NASH rats. Tissue kinetic analyses were performed using a one-tissue, two-compartment (1T2C) and a two-tissue, three-compartment (2T3C) model using an image-derived input function (IDIF) for the left ventricle. We then conducted correlation analysis between standard uptake values (SUVs) or volume of distribution (V_T), evaluated using compartment kinetic analysis and integrin ?_v or ?₃ protein expression.

Results

Biochemical and histological evaluation confirmed the development of NASH rats. Integrin ?_v?₃ protein expression and hepatic SUV were higher in NASH- than normal rats. The hepatic activity of ¹⁸F-FPP-RGD₂ peaked rapidly after administration and then gradually decreased, whereas left ventricular activity rapidly disappeared. The 2T3C model was found to be preferable for ¹⁸F-FPP-RGD₂ kinetic analysis in the liver. The V_{T (IDIF)} for ¹⁸F-FPP-RGD₂, calculated using the 2T3C model, was significantly higher in NASH- than normal rats and correlated strongly with hepatic integrin ?_v and ?₃ protein expression. The strengths of these correlations were similar to those between SUV_60-90 min and hepatic integrin ?_v or ?₃ protein expression.

Conclusions

We have demonstrated that the V_{T (IDIF)} of ¹⁸F-FPP-RGD₂, calculated using kinetic modelling, positively correlates with integrin ?_v and ?₃ protein in the liver of NASH rats. These findings suggest that hepatic V_{T (IDIF)} provides a quantitative assessment of integrin ?_v?₃ protein in liver.

SUBMITTER: Hiroyama S

PROVIDER: S-EPMC7541810 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Publications

Quantitative evaluation of hepatic integrin αvβ3 expression by positron emission tomography imaging using 18F-FPP-RGD2 in rats with non-alcoholic steatohepatitis.

Hiroyama Shuichi S Rokugawa Takemi T Ito Miwa M Iimori Hitoshi H Morita Ippei I Maeda Hiroki H Fujisawa Kae K Matsunaga Keiko K Shimosegawa Eku E Abe Kohji K

EJNMMI research 20201007 1

<h4>Background</h4>Integrin αvβ3, which are expressed by activated hepatic stellate cells in non-alcoholic steatohepatitis (NASH), play an important role in the fibrosis. Recently, we reported that an RGD peptide positron emission tomography (PET) probe is useful as a predictor of hepatic fibrosis. Kinetic analysis of the RGD PET probe has been performed in tumours, but not in hepatic fibrosis. Therefore, we aimed to quantify hepatic integrin αvβ3 in a ...[more]

PMID: 33026561

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Dataset Information

Quantitative evaluation of hepatic integrin ?_v?₃ expression by positron emission tomography imaging using ¹⁸F-FPP-RGD₂ in rats with non-alcoholic steatohepatitis.

Background

Methods

Results

Conclusions

Publications

Quantitative evaluation of hepatic integrin α<sub>v</sub>β<sub>3</sub> expression by positron emission tomography imaging using <sup>18</sup>F-FPP-RGD<sub>2</sub> in rats with non-alcoholic steatohepatitis.

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OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Quantitative evaluation of hepatic integrin ?v?3 expression by positron emission tomography imaging using 18F-FPP-RGD2 in rats with non-alcoholic steatohepatitis.

Background

Methods

Results

Conclusions

Publications

Quantitative evaluation of hepatic integrin α<sub>v</sub>β<sub>3</sub> expression by positron emission tomography imaging using <sup>18</sup>F-FPP-RGD<sub>2</sub> in rats with non-alcoholic steatohepatitis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Quantitative evaluation of hepatic integrin ?_v?₃ expression by positron emission tomography imaging using ¹⁸F-FPP-RGD₂ in rats with non-alcoholic steatohepatitis.