Bisphosphonates Reduce Smoking-Induced Osteoporotic-Like Alterations by Regulating RANKL/OPG in an Osteoblast and Osteoclast Co-Culture Model

Round 1

Reviewer 1 Report

The authors analyzed the influence of bisphosphonates on smoking-induced osteoporotic-like alterations by regulating RANKL/OPG in an osteoblast and osteoclast co-culture model.The study is well performed and the manuscript is well written with a significant clinical relevance.

Reviewer 2 Report

The proposed study aims to evaluate the effects of BPs on CSE-affected cells, in an osteoblast and osteoclast co-colture model. This is a well-designed study and a very interesting approach.

I totally agree with the authors that it is insufficient to study osteoblast and osteoclasts separately, hence their approach to establish an in vitro supplement-free, co-culture system breaks the limitations that similar studies had in the past.

Materials and Methods are thoroughly explained; all the analyses as well. The statistic used is appropriate for this kind of studies. Immunofluorescent staining and microscopic methods were used. In addition, gene expressions were evaluated with PCR and protein levels using Dot Blot measurements.

The results are well-presented too. Authors studied the co-culture system in order to establish a basis for their approach. A variety of CSE concentrations levels were checked in order to evaluate the toxicity and result to the proper percentage for the study.

The main finding of this study is that BPs may be an effective treatment for osteoporosis in smokers. This is not a novel finding. However, the are several strong points; the various methods that were used, the detailed preparation of the study and of course,the co-culture approach.