Oral Macrocystis pyrifera Fucoidan Administration Exhibits Anti-Inflammatory and Antioxidant Properties and Improves DSS-Induced Colitis in C57BL/6J Mice

Round 1

Reviewer 1 Report

This paper describes a study of the effects of an orally administered fucoidan on a mouse model of colitis. Parameters measured were markers of inflammation and oxidative stress, and included clinical and histopathological assessments as well as biochemical measurements.  Fucoidans (from the brown seaweed Macrocystis pyrifera) were two different molecular weight preparations, and it was interesting to note that the lower molecular weight fraction was in most of the experiments more effective than the higher molecular weight fraction.

The investigation is well described and written in a clear style. There is a thorough discussion, setting the findings into a context of inflammatory and oxidative processes, and the abstract is a concise summary of the paper.

One small question; is it the case that challenge with DSS and treatment with fucoidan were started simultaneously and both continued through the full 7 days? It is important to distinguish between prophylactic treatment on the one hand and treatment in response to an existing condition on the other.

In addition, it is intriguing to note that one sulfated polysaccharide, DSS, causes colitis, and another sulfated polysaccharide, fucoidan, ameliorates its symptoms. Do the authors have any comments on this?

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 2 Report

Fucoidan from brown seaweed, is a well-known anti-inflammatory agent and emerging evidence indicates that fucoidan extracts from Macrocystis pyrifera (MPF and DP-MPF) may also modulate oxidative stress.

This study investigated the impact of fucoidan extracts, MPF and DP-MPF in a dextran sodium sulphate (DSS)-induced mouse model of acute colitis. The results indicated that MPF and DP-MPF significantly prevented body weight loss, improved the disease activity index (DAI), restored colon lengths, reduced the wet colon weight, reduced spleen enlargement, and improved the overall histopathological score. Consistent with the reported anti-inflammatory functions, fucoidan extracts, MPF and DP-MPF significantly reduced the colonic levels of myeloperoxidase (MPO), nitric oxide (NO), malondialdehyde (MDA) and increased the levels of antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT). In addition, MPF and DP-MPF significantly inhibited levels of pro-inflammatory cytokines in colon-derived tissues. In summary, the results indicate that MPF and DP-MPF exhibited anti-inflammatory and antioxidant effects representing a promising therapeutic strategy for the cure of IBD. The manuscript is well written, designed and the research was dome appropriately. I have just one minor comment.

At the end on introduction part there is need to clearly state the novelty of the research. What was done for the first time?

Author Response

Oral Macrocystis pyrifera fucoidan administration exhibits anti-inflammatory and antioxidant properties and improves DSS-induced colitis in C57BL/6J mice.

Reviewer 2 Comments

Question

At the end on introduction part there is need to clearly state the novelty of the research. What was done for the first time?

Answer

Thank you so much for reviewing the manuscript and we agree with the reviewer’s comment. Macrocystis Pyrifera fucoidan extracts (MPF and DP-MPF) have been shown for the first time in this investigation to exhibit anti-inflammatory and antioxidant properties in a DSS-induced colitis model in mice. We have added this at the end of the introduction line 107-109.