Review for 10.1186/s12876-015-0382-3 (2015)

Reviewer ’s report  
 
Title: Western diet -induced hepatic steatosis and alterations in the liver transcriptome in adult  
Brown -Norway rats  
 
Version: 0 Date: 05 Sep 2015  
 
Reviewer: Robert Schierwagen  
 
Reviewer's report:  
 
It was interesting to review the work of Roberts et. al. The questions raised by the authors are 
relevant in the field of NAFLD research and contribute to a better understanding of molecular 
mechanisms in early stages of NAFLD. The authors demonstrate that sub -chronic WD leads to 
dysregulation of genes related to lipid and cholesterol metabolism. Furthermore, initial 
precursors of hepatic inflammation are already upregulated in this early stage of NAFLD.  
 
Major comments  
 
1. There is a discrepancy between the shown western blots of p65  and the densitometry in 
Figure 3G. The shown blot suggest a marked upregulation in control rats compared to 
WD-fed rats, which is not substantiated by the densitometry, especially since standard 
error is quite high for the control rats. The authors should  provide new western blots to 
clarify their findings by showing comparisons of at least 2 control vs. 2 WD samples. 
This finding is also surprising, since the opposite would be expected, as it is shown in 
Table 3 for Rela mRNA (even though it is only sligh tly and not significant increased in 
WD).  
 
2. There is a discrepancy between hepatic and serum cholesterol levels. Hepatic levels of 
cholesterol are highly increased as shown by Oil Red O staining, while serum levels 
show only a trend. How is this explaine d?     
 
3. The authors should show mean ± standard deviation instead of standard error in all 
graphs and tables.  
 
Minor comments  
 
Page 3 line 30: add "of" between "30%" and "the adult"  
Page 3 line 34: please change from "excess" to "excessive"  
Page 7 line  212: please change "12,000xg" to "12,000g"  
Page 10 line 189 -190: please change the attribution to Pf4 data, since I could not found Pf4 data 
in Table 1, but only in Table 3  
Page 10 line 204: The phrase "contrary" is misleading, since you compare different  stages of 
NAFLD (sub -chronic vs. long -term feeding).  
Page 21 line 544: please change "(E &F)" to "(F & G)"; furthermore, please briefly describe 
results in Figure 3 as done for Figures 1 & 2.  
Please check the number of used animals. On page 4 line 64 8 W D-fed rats are mentioned and on 
page 5 line 95 there are mentioned only 6.  
Please check manuscript for comma placement  
 
Are the methods appropriate and well described?  
If not, please specif y what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
Yes 
 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects req uire further  
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing interests  
Please complete a declaration of  competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
organisation that may in any way gain or lose financially from the publication of this  
manuscript, eithe r now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose  
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents r elating to the content of the  
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
5. Do you have any other financial competing inter ests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below.  If your reply is yes to any, please give details below.  
 
I declare th at I have no competing interests.  
 
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