Review for 10.1186/s12876-020-01356-2 (2020)

Reviewer ’s report  
 
Title: Human translatability of the GAN diet -induced obese mouse model of non -alcoholic  
steatohepatitis  
 
Version: 0 Date: 06 Apr 2020  
 
Reviewer's report:  
 
In the present study the authors investigate the clinical translatability of the mice model GAN 
DIO-NASH by head -to-head comparison of liver biopsy histological and transcriptome changes 
with NASH patients. They show that liver lesions in mice w ere comparable with NASH patients, 
and histomorphometric analysis indicated comparable increases in markers of hepatic lipid 
accumulation, inflammation and collagen deposition. Also, gene analysis revealed comparable 
dynamics. They conclude that GAN DIO -NASH mice model demonstrates good clinical 
translatability thus usable for identifying therapeutic targets and characterizing novel drug 
therapies for NASH.  
The manuscript is interesting and well written but several issues should e addressed.  
Listed below m y specific comment:  
 
- It has been recently reported that simple steatosis (NAFL), which represents the early 
stage of the disease, seems to be associated to a worse eNOS impairment compared to 
steatohepatitis (NASH). What is the status of eNOS phosphoryla tion on serine 1177 in model 
GAN DIO -NASH mice and in patient's liver?  
 
- Clinical evaluation of endothelial dysfunction, measured via FMD, has shown to be 
worse in NASH than NAFL patients, confirming a worse endothelial dysfunction and, therefore, 
a high er risk of cardiovascular disease in NASH subjects. What is the vascular reactivity of 
resistance arteries in GAN DIO -NASH mice versus littermates? And in patients?  
 
- HOMA score must be reported both in mice and in humans.  
 
- It is necessary to add in fi gure 1 the immunohistochemistry performed at least on 
healthy mice, and if possible, on humans.  
 
- All graphs should be reported as Mean  SD, and absolute "p" values should be 
reported instead of qualitative statistical symbols.  
 
- how were the blood pressure levels in animals before and after diet?  
 
- Kit used for IL -2 and IL -4 seems to have a highly sensitive range 2.60 -5.89, 0.48 -0.70, 
respectively, but the authors did not detect these interleukins in both mice groups. I suggest 
removing these data from the table 4.  
 
 
 
 
Are the methods appropriate and well described?  
If not, please specify what is required in your commen ts 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.  
 
No 
 
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 manus cript 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 recommend additional statistical review  
 
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, f ees, funding, or salary from an 
organisation that may in any way gain or lose financially from the publi cation of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation t hat 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 curr ently applying for any patents  relating 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 interests?  
 
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.  
 
None  
 
I agree to the open peer review policy of the journal. I understan d that my name will be included 
on my report to the authors and, if the manuscri pt is accepted f or publication, my named report 
including any attachments I upload will be posted on the website along with the authors' 
responses. I agree for my report to be made available under an Open Access Creative Commons 
CC-BY license ( http://creat ivecommons.org/licenses/by/4.0/ ). I understand that any comments 
which I do not wish to be included in my named report can be in cluded as confidential comments 
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journ al