Reviewer's report
Title:Fluvastatin attenuates hepatic steatosis-induced fibrogenesis in rats
through inhibiting paracrine effect of hepatocyte on hepatic stellate cells
Version:2Date:10 September 2014
Reviewer: Paola Dongiovanni
Reviewer's report:
Fluvastatin attenuates hepatic steatosis-induced fibrogenesis in rats through
inhibiting paracrine effect of hepatocyte on hepatic stellate cells
Chong LW et al.
In this study Chong et al. aimed to investigate the in vitro and in vivo anti-fibrotic
properties of fluvastatin (Flu). In vitro, Flu inhibited PA-induced free-radical
production, NADPH oxidase gp91phox expression and NFkB nuclear
translocation in HepG2 cells and rat primary hepatocytes (PRHs). Moroever,
conditioned medium-induced #-SMA protein expression in HSC-T6 cells was
significantly suppressed in Flu-pretreatment group compared to those without
treatment. In vivo, Flu reduced steatosis and fibrosis scores, #-SMA protein
expression, mRNA expression of pro-inflammatory and pro-fibrogenic genes in
livers of CDAA rats. The authors concluded that PA-induced HSC activation
through paracrine effect of hepatocytes in vitro was significantly suppressed by
Flu-pretreatment. In CDAA rats Flu reduced hepatic steatosis and fibrosis by
mitigating inflammation and oxidative stress suggesting a possible therapeutic
role of Flu in NASH treatment.
Major comments:
1. In the paragraph "Histopathological examination," the authors described that
liver sections were stained with hematoxylin-eosin (H&E) or Sirius Red to
evaluate collagen distribution. The authors didn’t show representative images of
liver sections stained with H&E. Moreover, it seems that the images of sections
stained with Sirius Red have been acquired with different magnifications.
Therefore it is difficult to compare the images of the different treatments at 4 and
8 weeks. In table 1, authors reported a steatosis score of 3.00 in rats maintained
at CDAA diet for 4 and 8 weeks. However, the degree of steatosis seems greater
in rats fed CDAA diet for 8 weeks. Similarly the amount of steatosis does not
seem the same in rats treated with the low dose of' Flu at 4 weeks compared to
untreated rats. Moreover, it is difficult to compare the degree of fibrosis between
rats treated with CDAA+Flu [5] and CDAA+Flu [10] at 8 weeks.
2. Authors asserted that half of the animals from each group were sacrified after
4 weeks, while the rest were sacrified after 8 weeks. Does CDAA diet result in
weight loss? During the first weeks rats fed CDAA lose weight (about 67 g)
compared to controls. We should expect a further loss of weight at 8 weeks.
3. Authors have conducted in vitro experiments treating primary rats hepatocytes
with Flu at different concentrations. It would be interesting to isolate primary
hepatocytes from rats fed CDAA diet plus Flu at 4 and 8 weeks.
4. Have the authors tested higher concentrations of Flu in the in vivo model as
described in literature?
5. RT-PCR is a semiquantitative method. It would be better to assess gene
expression by qRT-PCR.
Level of interest: An article of limited interest
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a statistician.
Declaration of competing interests:
I declare that I have no competing interests
Reviewer's report
Title:Fluvastatin attenuates hepatic steatosis-induced fibrogenesis in rats
through inhibiting paracrine effect of hepatocyte on hepatic stellate cells
Version:2Date:10 September 2014
Reviewer: Paola Dongiovanni
Reviewer's report:
Fluvastatin attenuates hepatic steatosis-induced fibrogenesis in rats through
inhibiting paracrine effect of hepatocyte on hepatic stellate cells
Chong LW et al.
In this study Chong et al. aimed to investigate the in vitro and in vivo anti-fibrotic
properties of fluvastatin (Flu). In vitro, Flu inhibited PA-induced free-radical
production, NADPH oxidase gp91phox expression and NFkB nuclear
translocation in HepG2 cells and rat primary hepatocytes (PRHs). Moroever,
conditioned medium-induced #-SMA protein expression in HSC-T6 cells was
significantly suppressed in Flu-pretreatment group compared to those without
treatment. In vivo, Flu reduced steatosis and fibrosis scores, #-SMA protein
expression, mRNA expression of pro-inflammatory and pro-fibrogenic genes in
livers of CDAA rats. The authors concluded that PA-induced HSC activation
through paracrine effect of hepatocytes in vitro was significantly suppressed by
Flu-pretreatment. In CDAA rats Flu reduced hepatic steatosis and fibrosis by
mitigating inflammation and oxidative stress suggesting a possible therapeutic
role of Flu in NASH treatment.
Major comments:
1. In the paragraph "Histopathological examination," the authors described that
liver sections were stained with hematoxylin-eosin (H&E) or Sirius Red to
evaluate collagen distribution. The authors didn’t show representative images of
liver sections stained with H&E. Moreover, it seems that the images of sections
stained with Sirius Red have been acquired with different magnifications.
Therefore it is difficult to compare the images of the different treatments at 4 and
8 weeks. In table 1, authors reported a steatosis score of 3.00 in rats maintained
at CDAA diet for 4 and 8 weeks. However, the degree of steatosis seems greater
in rats fed CDAA diet for 8 weeks. Similarly the amount of steatosis does not
seem the same in rats treated with the low dose of' Flu at 4 weeks compared to
untreated rats. Moreover, it is difficult to compare the degree of fibrosis between
rats treated with CDAA+Flu [5] and CDAA+Flu [10] at 8 weeks.
2. Authors asserted that half of the animals from each group were sacrified after
4 weeks, while the rest were sacrified after 8 weeks. Does CDAA diet result in
weight loss? During the first weeks rats fed CDAA lose weight (about 67 g)
compared to controls. We should expect a further loss of weight at 8 weeks.
3. Authors have conducted in vitro experiments treating primary rats hepatocytes
with Flu at different concentrations. It would be interesting to isolate primary
hepatocytes from rats fed CDAA diet plus Flu at 4 and 8 weeks.
4. Have the authors tested higher concentrations of Flu in the in vivo model as
described in literature?
5. RT-PCR is a semiquantitative method. It would be better to assess gene
expression by qRT-PCR.
Level of interest: An article of limited interest
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a statistician.
Declaration of competing interests:
I declare that I have no competing interests
Please review this paper.
user
Reviewer's report
Title:Fluvastatin attenuates hepatic steatosis-induced fibrogenesis in rats
through inhibiting paracrine effect of hepatocyte on hepatic stellate cells
Version:2Date:10 September 2014
Reviewer: Paola Dongiovanni
Reviewer's report:
Fluvastatin attenuates hepatic steatosis-induced fibrogenesis in rats through
inhibiting paracrine effect of hepatocyte on hepatic stellate cells
Chong LW et al.
In this study Chong et al. aimed to investigate the in vitro and in vivo anti-fibrotic
properties of fluvastatin (Flu). In vitro, Flu inhibited PA-induced free-radical
production, NADPH oxidase gp91phox expression and NFkB nuclear
translocation in HepG2 cells and rat primary hepatocytes (PRHs). Moroever,
conditioned medium-induced #-SMA protein expression in HSC-T6 cells was
significantly suppressed in Flu-pretreatment group compared to those without
treatment. In vivo, Flu reduced steatosis and fibrosis scores, #-SMA protein
expression, mRNA expression of pro-inflammatory and pro-fibrogenic genes in
livers of CDAA rats. The authors concluded that PA-induced HSC activation
through paracrine effect of hepatocytes in vitro was significantly suppressed by
Flu-pretreatment. In CDAA rats Flu reduced hepatic steatosis and fibrosis by
mitigating inflammation and oxidative stress suggesting a possible therapeutic
role of Flu in NASH treatment.
Major comments:
1. In the paragraph "Histopathological examination," the authors described that
liver sections were stained with hematoxylin-eosin (H&E) or Sirius Red to
evaluate collagen distribution. The authors didn’t show representative images of
liver sections stained with H&E. Moreover, it seems that the images of sections
stained with Sirius Red have been acquired with different magnifications.
Therefore it is difficult to compare the images of the different treatments at 4 and
8 weeks. In table 1, authors reported a steatosis score of 3.00 in rats maintained
at CDAA diet for 4 and 8 weeks. However, the degree of steatosis seems greater
in rats fed CDAA diet for 8 weeks. Similarly the amount of steatosis does not
seem the same in rats treated with the low dose of' Flu at 4 weeks compared to
untreated rats. Moreover, it is difficult to compare the degree of fibrosis between
rats treated with CDAA+Flu [5] and CDAA+Flu [10] at 8 weeks.
2. Authors asserted that half of the animals from each group were sacrified after
4 weeks, while the rest were sacrified after 8 weeks. Does CDAA diet result in
weight loss? During the first weeks rats fed CDAA lose weight (about 67 g)
compared to controls. We should expect a further loss of weight at 8 weeks.
3. Authors have conducted in vitro experiments treating primary rats hepatocytes
with Flu at different concentrations. It would be interesting to isolate primary
hepatocytes from rats fed CDAA diet plus Flu at 4 and 8 weeks.
4. Have the authors tested higher concentrations of Flu in the in vivo model as
described in literature?
5. RT-PCR is a semiquantitative method. It would be better to assess gene
expression by qRT-PCR.
Level of interest: An article of limited interest
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a statistician.
Declaration of competing interests:
I declare that I have no competing interests
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