Review for 10.1186/s12876-017-0652-3 (2017)

Reviewer ’s report  
 
Title:  Efficacy of Glutathione for the Treatment of Nonalcoholic Fatty Liver Disease: An Open -
label, Single -arm, Multicenter, Pilot Study  
 
Version: 0 Date: 16 Apr 2017 
 
Reviewer:  Jan Boren  
 
Reviewer’s report:  
 
The authors have in a small (n=29) open label, single -arm, multicenter study, investigated the 
therapeutic effects of 4 months of the antioxidant reduced L -glutath ione (GSH) treatment (300 
mg/day GSH for 4 months) on patients with nonalcoholic fatty liver disease (NAFLD). The 
results show that reduction in ALT levels (primary outcome), as well as reductions in 
triglyceride, NEFA, and ferritin levels. In ALT responde rs defined as patients showing a ≥12.9% 
reduction from baseline, GSH treatment significantly decreased CAP values as a marker of liver 
steatosis.  
 
 
This is an interesting study, There are however several major comments:  
 
1. The authors should measure plasma concentration of γ -L-glutamyl -L-cysteinyl -glycine in 
samples from before and during the study. Do the plasma levels correspond to ALT and CAP 
values?  
 
2. In this study design, several confounding factors may influence th e results. Another arm 
(or cross -over design) should be added with placebo.  
 
3. The drop out during the study was almost 10% - very high  
 
4. Please add waist circumference data  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the nec essary 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.  
 
Unable to assess  
 
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 require 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:  
 
Needs some language corrections before being published  
 
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, either 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 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.  
 
No 
 
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