Harnessing Mechanosensation in Next Generation Cardiovascular Tissue Engineering
, Marianna Barbuto 1, Giacomo Bernava 1 and Maurizio Pesce 1Round 1
Reviewer 1 Report
The review highlighted current efforts to assess the relevance of mechanical sensing into pathology modeling and manufacturing criteria for a next generation of cardiovascular tissue implants.
The topic is novel, and the impact is potentially significant. However, this review suffered from major defects in logic and writing that prevented it from being publishable.
The knowledge gap that this review intends to fill was not well defined. In addition, the reviewer noticed that large portions of this manuscript were devoted to rewriting isolated experimental results (such as Section 2.1), with little synthesis, connection, or critique. For review authors, originality is perhaps the single most important aspect (justification for writing the review in the first place). For readers, the manuscript in its current form does not provide sufficient insight beyond a reasonably up-to-date bibliography.
The organization of main sections is not well defined and chaotic. First of all, the Introduction failed to define the topic and relevant background in the first place. In fact, the content of the Introduction is logically unrelated to the subsequent sections 2-4. Second, for Sections 2-4, each beginning section of “mechanosensation” was logically isolated from subsequent review of “tissue engineering”. There is a lack of integrity in logic flow within each of Section 2, 3, and 4. The titles of Section 2 “Heart” is in accurate. Instead, this section only dealt with “Myocardium”.
For Section 2.2, the authors missed most important recent advances in gene editing, such as CRISPR/Cas9, class II CRISPR/Cas system (CRISPR/Cpf1) and RNA editing.
Section 4 seems to have a better logical flow than other sections. However, the endothelial Hippo signaling and KLF2-dependent mechanosensing was disappointingly omitted from this section.
Use of English language is below standard. The writing contains large number of vague sentences, poor or inaccurate choice of words, and some grammatical errors (e.g. line 44 “Research is today engaged in…”). “(RE)GENERATE” in the title is not even a standard word, which should be changed to REGENERATE in title. The figure legends are particularly incomplete and lacks critical details. For instance, what does it mean to have “cardiomyocytes” in yellow and blue in Fig 1? There are erroneous capitalization of words, such as “Investigators” in line 135, “Calcific Aortic Valve Disease” in line 164, and “Researchers” in line 356. The authors were not paying attention to the readability of the text.
Non-standard abbreviations were not spelt out at their FIRST appearance. Non-standard examples include PCL, PLLA etc.
The above major defects indicates this review is below publication standards. I recommend rejection.
Author Response
The review highlighted current efforts to assess the relevance of mechanical sensing into pathology modeling and manufacturing criteria for a next generation of cardiovascular tissue implants.
The topic is novel, and the impact is potentially significant. However, this review suffered from major defects in logic and writing that prevented it from being publishable.
We thank reviewer for her/his critical revision that prompted us to make (we hope) improvements in our writing.
The knowledge gap that this review intends to fill was not well defined. In addition, the reviewer noticed that large portions of this manuscript were devoted to rewriting isolated experimental results (such as Section 2.1), with little synthesis, connection, or critique. For review authors, originality is perhaps the single most important aspect (justification for writing the review in the first place). For readers, the manuscript in its current form does not provide sufficient insight beyond a reasonably up-to-date bibliography.
The aim of Section 2.2 was to introduce the readers to the general concept of cell mechanosensation and its implications in the fibrotic progression of myocardium. In the context of a review article that has to explain unfamiliar concepts to most of the readers, a thorough revision of the literature is necessary to let them understand the general topic. We therefore left the section as it is, as it is relevant to what discussed in 2.2.
The organization of main sections is not well defined and chaotic. First of all, the Introduction failed to define the topic and relevant background in the first place. In fact, the content of the Introduction is logically unrelated to the subsequent sections 2-4. Second, for Sections 2-4, each beginning section of “mechanosensation” was logically isolated from subsequent review of “tissue engineering”. There is a lack of integrity in logic flow within each of Section 2, 3, and 4. The titles of Section 2 “Heart” is in accurate. Instead, this section only dealt with “Myocardium”.
We respectfully disagree with reviewer about the lack of logics in the organization of the manuscript. Each of the chapters is divided in two sections. The first dedicated to relevance of mechanosensation in pathologic evolution of the cardiovascular system; the second to options, which could be explored to convey the mechanosensation concept into approaches to generate or regenerate the myocardium more efficiently. The introduction was kept very short intentionally to avoid repetitions in the following text. In order to make it more straightforward we shortened it further in the revised version (lines 27-53). We hope that reviewer can now appreciate our logic.
For Section 2.2, the authors missed most important recent advances in gene editing, such as CRISPR/Cas9, class II CRISPR/Cas system (CRISPR/Cpf1) and RNA editing.
We added details on this and other aspects that we judged relevant in the context of section 2.2 (lines 109-119) thank you.
Section 4 seems to have a better logical flow than other sections. However, the endothelial Hippo signaling and KLF2-dependent mechanosensing was disappointingly omitted from this section.
The necessary information on the KLF2/Hippo pathway has been introduced in the revised version of the manuscript (lines 420-422 and 435-437), thank you.
Use of English language is below standard. The writing contains large number of vague sentences, poor or inaccurate choice of words, and some grammatical errors (e.g. line 44 “Research is today engaged in…”). “(RE)GENERATE” in the title is not even a standard word, which should be changed to REGENERATE in title. The figure legends are particularly incomplete and lacks critical details. For instance, what does it mean to have “cardiomyocytes” in yellow and blue in Fig 1? There are erroneous capitalization of words, such as “Investigators” in line 135, “Calcific Aortic Valve Disease” in line 164, and “Researchers” in line 356. The authors were not paying attention to the readability of the text.
Although unusual, the term (re)generate in the title helps to summarize the concept that tissue engineering criteria can be employed to generate and/or regenerate pathologic tissues. This concept would be difficult to explain without merging the two terms. We thus left it in the title, hoping that reviewer agrees. We corrected misspelling and incorrect capitalization where necessary, thank you.
Non-standard abbreviations were not spelt out at their FIRST appearance. Non-standard examples include PCL, PLLA etc.
We corrected the definition of the abbreviations where necessary, thank you.
The above major defects indicates this review is below publication standards. I recommend rejection.
We hope that with the extensive modifications we made the reviewer changes her /his mind on our manuscript. On the other hand, in our opinion, none of the ‘defects’ highlighted by reviewer jeopardizes the take home message of the manuscript.
Reviewer 2 Report
This is a very interesting and well-written review that gathers some aspects of current knowledge concerning the Mechano-Signaling within the cardiovascular system analyzing and discussing the emerging concepts for its potential therapeutic utilization in cardiac implants and regeneration
I suggest adding a table summarizing the main miRNAs involved in the activation/transduction of cardiovascular Mechano-Signaling to improve/facilitate the manuscript readability
Author Response
This is a very interesting and well-written review that gathers some aspects of current knowledge concerning the Mechano-Signaling within the cardiovascular system analyzing and discussing the emerging concepts for its potential therapeutic utilization in cardiac implants and regeneration
I suggest adding a table summarizing the main miRNAs involved in the activation/transduction of cardiovascular Mechano-Signaling to improve/facilitate the manuscript readability
We thank the reviewer for her/his comments that helped to improve the quality of our manuscript. We introduced the requested information on miRNAs chapter by chapter with a dedicated table, thank you.
Reviewer 3 Report
The review by Garoffolo et al is designed to outline mechanosensitive mechanisms involved in the pathologic remodeling of the cardiovascular system, particularly as it could be utilized to improve tissue engineering.The authors begin by briefly summarizing the role of mechanosensation in cardiac fibrosis, calcific aortic valve disease, and vascular disease. The authors also discuss approaches for how mechanosensation could be exploited in tissue engineering approaches to treat each disease.
In general, the topic of mechanosensation in cardiovascular disease is timely. However, the current manuscript focuses on the interaction between cells and the extracellular matrix (ECM) and only vaguely discusses mechanosensitive pathways that may be involved, decreasing the significance of this review. Furthermore, many of the topics discussed lack specific details, and development of key concepts or themes throughout the review would significantly improve its value and utility.
As currently presented, the review does not significantly add to the extensive literature on biomechanical regulation of the cardiovascular system. In addition, this current review manuscript is very similar in content and organization, but is not as well-constructed, as the review by the same authors published in Cells 2019.
Major comments
- The title of this manuscript is inaccurate as this review primarily focuses on the relationship between the ECM and cell behavior; not on how mechanosensitive mechanisms could be utilized in tissue engineering or regenerative approaches to treat cardiovascular disease. A potential reader would by mislead as to the content of the review from reading the title.
- This review gives minimal examples of mechanosensation outside of how cells can interact with the ECM. For example, how does ECM composition change with pathological mechanical forces? Are mechanical signals only transmitted through changes in ECM composition? Other critical mechanoregulatory stimuli in the cardiovascular system such as fluid flow dynamics or blood pressure are not covered in the review.
- This review lacks focus, giving vague details in some areas and very specific details in others. It is often unclear how the topic discussed relates to mechanosenstation. For example, is the Hippo pathway the only pathway that could be used to promote cardiomyocyte proliferation, what does this have to do with transforming cardiac fibroblasts into cardiomyocytes, and how is this related to mechanosensation and ECM composition?
- The approaches listed fail to take in consideration that tissue engineering often occurs in the absence of physiological mechanical forces and how this challenge might be overcome in the future.
- The review fails to acknowledge how laminar shear stress and oscillatory shear stress is also thought to play a role in calcific aortic valve disease as well as in vascular disease. For example, calcific aortic valve disease occurs primarily on the fibrosa side of the valve, or the side of the valve that is exposed to low, bidirectional flow. This seems to be an important concept that is left out in this review.
- The figures are not clearly related to mechanoregulation of the cardiovascular system and how it might relate to regeneration. For Figure 1 and Figure 2, it is unclear how they relate to mechanosensation. There is extensive information on how fluid dynamics affect heart valve development and disease that is not included in Figure 2. In Figure 3, the nature of the green tissue, yellow cells and pink shapes is not clear. In all cases, it is not clear how mechanosensation specifically affects myocardial, valvular or vascular tissue organization, homeostasis, or pathology.
- Multiple run-on sentences and misused words makes this review difficult to follow. The use of “so-called” multiple times is off putting.
- This review would benefit from a conclusion and perspectives section.
Minor comments
- Multiple grammatical errors makes this review difficult to follow.
Author Response
The review by Garoffolo et al is designed to outline mechanosensitive mechanisms involved in the pathologic remodeling of the cardiovascular system, particularly as it could be utilized to improve tissue engineering.The authors begin by briefly summarizing the role of mechanosensation in cardiac fibrosis, calcific aortic valve disease, and vascular disease. The authors also discuss approaches for how mechanosensation could be exploited in tissue engineering approaches to treat each disease.
In general, the topic of mechanosensation in cardiovascular disease is timely. However, the current manuscript focuses on the interaction between cells and the extracellular matrix (ECM) and only vaguely discusses mechanosensitive pathways that may be involved, decreasing the significance of this review. Furthermore, many of the topics discussed lack specific details, and development of key concepts or themes throughout the review would significantly improve its value and utility.
As currently presented, the review does not significantly add to the extensive literature on biomechanical regulation of the cardiovascular system. In addition, this current review manuscript is very similar in content and organization, but is not as well-constructed, as the review by the same authors published in Cells 2019.
Major comments
- The title of this manuscript is inaccurate as this review primarily focuses on the relationship between the ECM and cell behavior; not on how mechanosensitive mechanisms could be utilized in tissue engineering or regenerative approaches to treat cardiovascular disease. A potential reader would by mislead as to the content of the review from reading the title.
In order to address reviewer’s concern, we added a significant amount of information in the three main chapters of the manuscript. We hope that with the introduction of this new material we were able to focus our manuscript on translation of mechanosensation concepts in tissue engineering through an appropriate description of the pathways and molecular effectors potentially involved. On the other hand, relationship between cells and the surrounding matrix are the driving interactions in mechanosensation and to cover this is essential to guide the readers in this complex matter.
- This review gives minimal examples of mechanosensation outside of how cells can interact with the ECM. For example, how does ECM composition change with pathological mechanical forces? Are mechanical signals only transmitted through changes in ECM composition? Other critical mechanoregulatory stimuli in the cardiovascular system such as fluid flow dynamics or blood pressure are not covered in the review.
In the revised version of the manuscript, we provided new examples of signalling pathways potentially involved in intracellular transmission of mechanical forces not dependent on interactions of cells with the ECM but, for example, on pathological alterations in fluid dynamics. New text has been introduced at lines 420-422 and 435-437.
- This review lacks focus, giving vague details in some areas and very specific details in others. It is often unclear how the topic discussed relates to mechanosenstation. For example, is the Hippo pathway the only pathway that could be used to promote cardiomyocyte proliferation, what does this have to do with transforming cardiac fibroblasts into cardiomyocytes, and how is this related to mechanosensation and ECM composition?
The aim of section 2.2 was to provide an overview of the technologies that could be employed to induce reactivation of myocytes proliferation or potentially promoting conversion of CFs into cardiomyocytes in a mechanosensing permissive environment. Thus, although none of the literature cited was contextualizing the reprogramming of CFs into CMs in a mechanically ‘permissive’ environment, we wanted to point the attention and raise the interest on possible new combined approaches. Our hypothesis is clearly stated at lines 179-207.
- The approaches listed fail to take in consideration that tissue engineering often occurs in the absence of physiological mechanical forces and how this challenge might be overcome in the future.
In order to address reviewer’s remark, we added a conclusion and future perspective section where this concept is clearly established (lines 546-560).
- The review fails to acknowledge how laminar shear stress and oscillatory shear stress is also thought to play a role in calcific aortic valve disease as well as in vascular disease. For example, calcific aortic valve disease occurs primarily on the fibrosa side of the valve, or the side of the valve that is exposed to low, bidirectional flow. This seems to be an important concept that is left out in this review.
We have introduced this important concept at lines 259-270 in the revised manuscript, thank you
- The figures are not clearly related to mechanoregulation of the cardiovascular system and how it might relate to regeneration. For Figure 1 and Figure 2, it is unclear how they relate to mechanosensation. There is extensive information on how fluid dynamics affect heart valve development and disease that is not included in Figure 2. In Figure 3, the nature of the green tissue, yellow cells and pink shapes is not clear. In all cases, it is not clear how mechanosensation specifically affects myocardial, valvular or vascular tissue organization, homeostasis, or pathology.
We have changed either the layout and the conceptual content of the three figures. We hope to have improved the clarity of these representations, thank you.
- Multiple run-on sentences and misused words makes this review difficult to follow. The use of “so-called” multiple times is off putting.
We have corrected these errors, thank you
- This review would benefit from a conclusion and perspectives section.
See answer to specific comment #4, thank you.
Round 2
Reviewer 1 Report
It is a delight to see significant improvement to the revised manuscript. The review appreciate the efforts made by the authors, which not only included new information key to the topic, but significantly enhanced the overall impact to this review. My previous comments have been addressed. I recommend acceptance of the revision.
Author Response
It is a delight to see significant improvement to the revised manuscript. The review appreciate the efforts made by the authors, which not only included new information key to the topic, but significantly enhanced the overall impact to this review. My previous comments have been addressed. I recommend acceptance of the revision.
We thank very much the reviewer for her/his comment.
Reviewer 2 Report
The authors carefully and precisely addressed the concerns raised by this reviewer.
Author Response
The authors carefully and precisely addressed the concerns raised by this reviewer.
We thank very much the reviewer for her/his comment.
Reviewer 3 Report
The manuscript is improved with the addition of more information on mechanical forces and miRNA content. The revised figures also are much improved.
Additional subheadings and clear organization would aid a reader in comprehending the broad content presented.
The title still does not seem to accurately reflect the content of the review which is more oriented towards tissue engineering.
Author Response
The manuscript is improved with the addition of more information on mechanical forces and miRNA content. The revised figures also are much improved.
We thank very much the reviewer for her/his comment.
Additional subheadings and clear organization would aid a reader in comprehending the broad content presented.
We made the necessary changes, thank you.
The title still does not seem to accurately reflect the content of the review which is more oriented towards tissue engineering.
We have modified the title to better conform to the content of the manuscript, thank you.
