Advancements in Peripheral Nerve Injury Research Using Lab Animals
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
This review attempts to describe the strengths and limitations of the wide range of pre-clincal animal models available to researchers - highlighting the importance of choosing particular nerves of particular species to model human peripheral nerve injury. The amount of information available for such a review is large and presents a difficult task of choosing the most appropriate citations to include to provide a clear and concise distillation of the most relevant information.
Unfortunately, there appeared was a lot of detail that was missing from the manuscript giving the impression that there was relatively little depth to the review. I was also forced to guess the intended meanings in several parts of the review. My attempts to get a better understanding of the text by checking the citations provided in the reference list often didn't help. I was left with the impression that, on several occasions, either an inappropriate citation had been chosen or that an error had occurred during the compilation of the references list. Some parts of the review were also rather confusing and require clarification (a list of the major and minor comments/suggestions has been provided).
Author Response
Comments 1: This review attempts to describe the strengths and limitations of the wide range of pre-clincal animal models available to researchers - highlighting the importance of choosing particular nerves of particular species to model human peripheral nerve injury. The amount of information available for such a review is large and presents a difficult task of choosing the most appropriate citations to include to provide a clear and concise distillation of the most relevant information.
Unfortunately, there appeared was a lot of detail that was missing from the manuscript giving the impression that there was relatively little depth to the review. I was also forced to guess the intended meanings in several parts of the review. My attempts to get a better understanding of the text by checking the citations provided in the reference list often didn't help. I was left with the impression that, on several occasions, either an inappropriate citation had been chosen or that an error had occurred during the compilation of the references list.
Thank you for your review. Unfortunately, we were unable to identify the specific sections you referenced. We would be happy to revise and add details as needed if you could kindly provide further guidance. We apologize if any citations were inadvertently mixed up during compilation; however, we have reviewed each one to ensure their relevance and appropriateness.
Comments 2: Some parts of the review were also rather confusing and require clarification (a list of the major and minor comments/suggestions has been provided).
We appreciate your feedback that there are additional comments and suggestions for improvement. However, we do not see a specific list of these major and minor points in the information provided. We would be happy to address each one thoroughly to enhance the manuscript if you could provide us with that list.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authors
The authors review the field of experimental peripheral nerve injury (PNI) research in a translational perspective. Various animal models, nerve injury models, and outcome assessments are discussed in relation to species, type of nerve injury and objectives of the experiments. The manuscript is well organized, and its presentation clear and focused. The review covers all key aspects of PNI experimental research, although in a relatively condensed manner. This provides easy access for readers to the receive and overview of the basics of experimental PNI research. The reference list is up-to-date and allows the reader to obtain more details.
Author Response
Comment 1: The authors review the field of experimental peripheral nerve injury (PNI) research in a translational perspective. Various animal models, nerve injury models, and outcome assessments are discussed in relation to species, type of nerve injury and objectives of the experiments. The manuscript is well organized, and its presentation clear and focused. The review covers all key aspects of PNI experimental research, although in a relatively condensed manner. This provides easy access for readers to the receive and overview of the basics of experimental PNI research. The reference list is up-to-date and allows the reader to obtain more details.
Response 1: Thank you very much for taking the time to review this manuscript. We truly appreciate your review.
Reviewer 3 Report
Comments and Suggestions for Authors
Peripheral nerve injuries (PNI) are a common clinical challenge caused by trauma, compression, or iatrogenic factors. Despite the regenerative abilities of the peripheral nervous system, current treatment methods often yield inconsistent outcomes. In the present review authors, explore animal models used in PNI research, evaluating different types of nerve injuries, their efficacy, and study design elements.
Recommendation
The article is well-written, cites suitable and recent papers, and provides in-depth knowledge.
Minor suggestions
- Present a summary of various animal models, including their strain, key characteristics, and applications in Peripheral Nerve Injury (PNI) research in a tabular format.
- Authors may also compile and summarize published studies that highlight the potential of laboratory animals in peripheral nerve repair.
Author Response
Peripheral nerve injuries (PNI) are a common clinical challenge caused by trauma, compression, or iatrogenic factors. Despite the regenerative abilities of the peripheral nervous system, current treatment methods often yield inconsistent outcomes. In the present review authors, explore animal models used in PNI research, evaluating different types of nerve injuries, their efficacy, and study design elements.
The article is well-written, cites suitable and recent papers, and provides in-depth knowledge.
Comments 1: Present a summary of various animal models, including their strain, key characteristics, and applications in Peripheral Nerve Injury (PNI) research in a tabular format.
Response 1: Thank you for your valuable feedback and suggestions. We have added Tables 1 (small animals) and 2 (large animals) to the manuscript, summarizing the strengths, applications, and limitations of various animal models.
Comments 2. Authors may also compile and summarize published studies that highlight the potential of laboratory animals in peripheral nerve repair.
Response 2: Thank you for your suggestion. We have added Table 4, which summarizes all the published experimental studies we reviewed, outlining the study title, animal model, technique, and outcome.
Reviewer 4 Report
Comments and Suggestions for Authors
The article entitled “Advancements in Peripheral Nerve Injury Research Using Lab Animals” This review delves into the animal models commonly used in PNI research, ranging from non-mammalian species to rodents and larger mammals, such as sheep, swine, dogs, and non-human primates.
Below are some suggestions:
- As this is a review manuscript, I suggest that the authors emphasize the contribution and impact of the subject to the scientific community and clinical application in the abstract, as there is a lot of research in the literature on peripheral nerve regeneration. I also find it interesting to include the main results.
- The manuscript doesn't include any pictures. I suggest at least two images, for example, one showing the main items (animals/nerves used).
- Given the information collected in the literature, what is the group's critical opinion in relation to the results?
- For better visualization, I suggest the authors include tables with the main articles found and analyzed in each of the items, for example, types of animals....
- 2.0. Selection of Peripheral Nerve Model in Animal Studies: There are many articles on studies related to the facial nerves, such as the facial nerve, trigeminal nerve.....why wasn't it mentioned?
- I suggest that the authors create a separate section on the main techniques/treatments for regenerating the peripheral nervous system, including some current ones, such as glues/adhesives.
- What is the potential of clinical applicability? What would be the contribution to the community and the impact? Maybe add the conclusion.
Comments on the Quality of English Language
Moderate editing.
Author Response
Reviewer 4:
The article entitled “Advancements in Peripheral Nerve Injury Research Using Lab Animals” This review delves into the animal models commonly used in PNI research, ranging from non-mammalian species to rodents and larger mammals, such as sheep, swine, dogs, and non-human primates.
Below are some suggestions:
Comments 1: As this is a review manuscript, I suggest that the authors emphasize the contribution and impact of the subject to the scientific community and clinical application in the abstract, as there is a lot of research in the literature on peripheral nerve regeneration. I also find it interesting to include the main results.
Response 1: Thank you for your review and thoughtful feedback. As suggested, we have highlighted the impact of peripheral nerve regeneration in the abstract; please see lines 27–32.
Comments 2: The manuscript doesn't include any pictures. I suggest at least two images, for example, one showing the main items (animals/nerves used).
Response 2: Thank you for your suggestion. We have added three figures: Figure 1 (lines 91-109) presents a cross-section of the porcine sciatic nerve; Figure 2 (lines 120-140) illustrates the median and ulnar nerves in a porcine model; and Figure 3 (lines 792-815) compares simple repair versus gap repair using suture repair and PEG fusion in a porcine median nerve model.
Comments 3: Given the information collected in the literature, what is the group's critical opinion in relation to the results?
Response 3: Thank you for this insightful question. Based on the literature and our own experience, we believe animal models are indispensable for advancing peripheral nerve research. We concur with the findings presented in the review and have incorporated models such as rats and pigs in our studies, applying several of the described techniques for investigating peripheral nerve injury. Our work highlights the critical importance of standardization across experimental protocols to reduce variability, enhance reproducibility, and ultimately improve the translatability of preclinical findings to clinical applications.
Comments 4: For better visualization, I suggest the authors include tables with the main articles found and analyzed in each of the items, for example, types of animals....
Response 4: Thank you for your suggestion. It appears that our tables were inadvertently omitted from the initial submission. We have now included Tables 1 (lines 286-287), 2 (335-336), 3 (399-400), and 4 (402-406) which summarize the findings of the main articles analyzed, including animal types, injury models, and key applications.
Comments 5: 2.0. Selection of Peripheral Nerve Model in Animal Studies: There are many articles on studies related to the facial nerves, such as the facial nerve, trigeminal nerve.....why wasn't it mentioned?
Response 5: Thank you for bringing this to our attention. Given the authors' backgrounds, the initial focus is on peripheral nerves commonly studied in orthopedic, hand, and plastic surgery research. However, we agree that the facial and trigeminal nerves are important within the broader scope of peripheral nerve research. In response, we have added two paragraphs addressing these nerves. Please see lines 186-194 and 196-202.
Comments 6: I suggest that the authors create a separate section on the main techniques/treatments for regenerating the peripheral nervous system, including some current ones, such as glues/adhesives.
Response 6: Thank you for this suggestion. We have added table 4 (lines 402-406) summarizing the main studies included in our review, highlighting the potential of laboratory animals in peripheral nerve repair.
Comments 7: What is the potential of clinical applicability? What would be the contribution to the community and the impact? Maybe add the conclusion.
Response 7: Thank you for your suggestion. We have addressed the clinical applicability and the broader impact of peripheral nerve regeneration on the treatment of peripheral nerve injuries in the conclusion. These additions highlight the study’s relevance and contribution to both the scientific and clinical communities. Please see lines 833-838.
Round 2
Reviewer 1 Report
Comments and Suggestions for Authors
my apologies for forgetting to attach my comments in the last review. Even without my comments, I can see that the manuscript has been improved by the authors. However, there are still many major and minor points that I find confusing (that require clarification) and some points that I don't agree with (see attched file for detailed list of these points). The citations have been improved but there are still some remaining issues/errors (all highlighted in the attached file). Overall, I believe that the review can be improved by providing more detail and highlighting more the relative advantages and disadvantages of the animal models (see attached file).
Comments for author File: Comments.pdf
Comments on the Quality of English Language
The manuscript is generally well written but a few sentences were difficult to follow (indicated in the attached file).
Author Response
Major:
Comments 1: Lines 52-53: “Non-mammalian species provide unique insights into nerve regeneration and new treatment approaches [7-10]. It would be useful if the authors could give a few examples of the unique insights into nerve regeneration and treatment options afforded by the use of non-mammalian species.
Response 1: Thank you for your feedback. As suggested, we provided a few examples of the unique insights into nerve regeneration and treatment options in lines 55-61.
Comments 2: The image for Figure 2 is not sharp. Please replace it with a better image
Response 2: Thank you for bringing this to our attention. We have replaced Figure 2 with an updated, clearer version.
Comments 3: Line 91-92: The adult pig median nerve is composed of multiple nerve fascicles, as is the adult human median nerve. I presume that Figure 2 shows the epineurial sheath of the median nerve trunk, which surrounds/contains the inner nerve fascicles. Please modify your description accordingly. Also reader confusion is compounded by figure legend 2 stating that the image is from a porcine animal but in line 117, the text states that it is from a non-human primate.
Response 3: Thank you for bringing this to our attention. We apologize for any confusion. We have amended the description in lines 113-114, revised the paragraph regarding the ulnar nerve in line 190, and updated the Figure 2 legend accordingly. The image now accurately depicts the ulnar and median nerves in a porcine model.
Comments 4: Line 99: Citation 3 doesn’t appear to be appropriate as it doesn’t mention self-harm affecting animal well being. By self-injurious behaviour, I am guessing that the authors are referring to auto-mutilation by toe-biting.
Response 4: Thank you for your comment. Citation 3 is referenced here because it discusses the consequences of severe nerve injury, specifically noting that "when the injury is serious, neurotrophic changes may occur, resulting in paralysis of the innervated muscles and loss of joint function," which establishes the basis for subsequent complications. Citations 26 and 28 specifically address the development of self-mutilation behaviors, such as toe-biting, that can arise secondary to the paralysis and functional loss. We have clarified the text to better distinguish the role of each reference. Please see lines 116-119.
Comment 5: Lines 109-111: “The radial nerve, although rarely used in PNI animal studies due to its small diameter, controls elbow extension and wrist and digital movement, assessing function across a single joint.”I do not understand - please clarify how the influence of the radial nerve on elbow, wrist and finger extension can be regarded as “assessing function across a single joint.”
Response 5: Thank you for bringing this to our attention. In their study, O'Daly et al. demonstrated that the quality of nerve repair alignment can predict voluntary function across a single joint by assessing reinnervation of flexor and extensor muscle groups. However, because this concept is not unique to the radial nerve, is not central to the focus of this section, and may lead to confusion, we have removed the statement for clarity.
Comment 6: Line 119: My understanding of human anatomy is that elbow flexion is controlled by the musculocutaneous nerve and arm abduction is largely controlled by the axillary nerve activating the deltoid muscle. Lines 117-118: “Assessments have been conducted using quantitative forelimb strength measurements, isometric pull tasks, and the Bertlelli test for elbow flexion and abduction.” .I think that the isometric pull test is related to a situation where both median and ulnar nerves were injured. The Bertelli test was applied in a report of ulnar to musculcutaneous nerve transfer in rats and so appears to be a muisunderstanding of the information in the literature by the authors
Response 6: Thank you for your comment. We agree with your anatomical clarification that elbow flexion is primarily mediated by the musculocutaneous nerve and that arm abduction is largely controlled by the axillary nerve through activation of the deltoid muscle.
Regarding the functional assessments: you are correct that the isometric pull task has been applied in studies where the median and ulnar nerves were injured, and that the Bertelli test specifically assesses recovery following ulnar-to-musculocutaneous nerve transfers in rodent models.
To address this, we have revised the paragraph to more accurately distinguish between the nerve functions involved and the specific contexts in which each functional assessment is used. Please see the updated text in lines 194-200. We appreciate your guidance in helping to improve the clarity and accuracy of this section.
Comments 7: Lines 124-125: “Functional recovery can be assessed through the toe-spreading reflex, gait analysis, force threshold measurements, and gastrocnemius muscle testing [27].” This comment appears in the text relating to tibial nerve activity, but toe extension and speading is associated with both tibial and peroneal nerve activity. Please clarify.
Response 7: Thank you for your comment. We agree that toe extension and spreading involve contributions from both the tibial and common peroneal nerves. We have revised the text to clarify the specific functional assessments associated with each nerve. Please see the updated section in lines 213-215.
Comments 8: Lines 128-130: “Compared to the tibial nerve, the peroneal nerve exhibits inferior recovery capacity, making it a model for studying poor regeneration outcomes [27]” There is limited information presented here - by what outcome measures is the regeneration of the peroneal nerve inferior to that of the tibial nerve? What mechanism(s) are reported to contribute to the poorer regeneration of this nerve?
Response 8: Thank you for your comment. We have clarified that inferior regeneration of the common peroneal nerve compared to the tibial nerve is supported by molecular differences (protein synthesis and gene expression) described by Lin et al., and by electrophysiological findings (lower CMAP amplitudes and axonal density) reported by Zhang et al. Please see lines 216-226.
Comments 9: Lines 183-186: Rana pipiens (R. pipiens, northern leopard frog) have been employed to investigate optic nerve regeneration, examining the effects of ciliary neurotrophic factor and fibroblast growth factor on regenerating axons. [38] Bearing in mind the stated goals of the review being to inform the reader as to the importance of choosing particular nerves in particular animal models, can the authors clarify if there is a particular advantage of choosing this nerve and animal model for the study? Simply stating that this species was chosen for that study doesn’t seem to meet the goals of the review
Response 9: Thank you for your feedback. We have clarified the rationale for using the optic nerve in Rana pipiens within the context of model selection. Please see lines 280-285.
Comments 10: Lines 197-199: I think the authors have accidentally included a false terminology in which they state that “in mice, 1.5 cm in rats, and 3.0 cm in rabbits, compared to 4 cm in pigs and humans [5,26].”. It seems that should be referring to the term “critical nerve defect” which was defined in their citation #26 as “a nerve gap over which no recovery will occur without some form of nerve grafting or bridging”. This is very different in meaning from the description provided by the authors and their description should be corrected.
Response 10: Thank you for pointing this out. You are correct that the term “critical nerve defect” more accurately describes the concept in question. We have updated the text to use this correct terminology and clarified the definition in line with citation #27. Please see lines 297-300.
Comments 11: Lines 332-339 “Siwei et al… 46,54] #46 and #54 are not authored by Siwei.
Response 11: Thank you for catching this error. The attribution to Siwei et al. was incorrect, and the citation has been updated to the appropriate source (citation #3). Please see the corrected text in lines 473-476.
Comments 12: Lines 435-437: Unlike the crush injury model, this approach retains the endoneurium and perineurium, while disrupting axonal continuity. This cannot be correct cutting axons with microscissors would not spare the endoneurium or perineurium. Please clarify your statement
Response 12: Thank you for your comment. We have clarified the description to more accurately reflect the methodology and anatomical impact of the model. Please see the revised text in lines 588-590.
Comments 13: Line 540-541: ”Magnetic Reconance Imaging (MRI) is utilized 540 to visualize nerve structure and monitor recovery [25,73-75]. I cannot find any relevant comment about MRI in citations #25 or #74 - also citation #74 focusses on ultrasound, not MRI.
Response 13: Thank you for noting this. You are correct that citations #25 and #74 do not support the statement regarding MRI. It appears the references were inadvertently misaligned during revisions. We have corrected the references and revised the text accordingly to ensure that only appropriate sources are cited for each imaging modality. Please see the updated section in lines 698-700
Comments 14: Lines 554-555: “High-resolution ultrasound imaging assesses nerve morphology and detects structural changes such as nerve swelling, fibrosis, and neuroma formation [73,79].” Citation #73 is an MRI study, not an ultrasound study.
Response 14: Thank you for catching this error. You are correct that citation #73 refers to an MRI study. We have removed the incorrect reference and replaced it with appropriate citations: Zhu et al. (citation #95) and Ricci et al. (citation #100). Please see the corrected text in lines 713-714.
Comments 15: Lines 657-659: “Emerging techniques, such as polyethylene glycol-mediated fusion (PEG fusion) in pigs and bio-scaffolds in rats, are under investigation [92,93] (Figure 3). Polyethylene glycol-mediated fusion of what in pigs? Also, which nerves were studied and what were the outcomes parameters and results more detail please. The same detail is also missing for the bio-scaffold rat study.
Response 15: Thank you for the suggestion; we have included the suggested details, please see lines 828-843.
Minor:
Comments 16: Line 64: the word “advancements” needs to be changed to “advances”
Response 16: Thank you, we have made the suggested modification, please see line 72.
Comments 17: Line 81 Figure 1 legend: please state which type of pig was used for demonstrating the exposed sciatic nerve. Also state whether the animal is in a prone or supine position for the surgery which will help in the understanding as to whether the surgical approach to the pig leg is medial or lateral. Unfortunately the cranial, cuadal, dosal, and ventral indications aren’t helping me figure out the orientation. In fact, the use of cranial and caudal seem to be inappropriate since limb orientation is normally described using the terms proximal and distal (please clarify this point). The inclusion of a scale bar would be very informative in giving an impression of size. The same concerns for limb orientation, surgical approach and image scale bar also apply to Figure 2 and its legend (line 90).
Response 17: Thank you for the suggestion. We have updated the figure legends for both figures to clarify the animal type and surgical positioning. We also revised the anatomical descriptors to use “proximal” and “distal” to align with standard limb orientation terminology. Additionally, a scale bar has been added to provide context regarding anatomical size. Please see lines 113-114 and 162-164.
Comments 18: Lines 253-255 “Established age equivalences to account for variations in regenerative capabilities, with one-year-old sheep corresponding to young adults [15,32,48]. This sentence doesn’t make any sense. Please modify text to clarify the intended meaning.
Response 18: Thank you. We have revised the sentence to ensure clarity, please see lines 356-358.
Comments 19: Lines 258-259 “However, studies in sheep generally last 1 to 12 months due to the slower pace of nerve regeneration [27]” State what the measured pace is in sheep and how this compares to the rate of human axon regeneration.
Response 19: Thank you for the feedback, we added the comparison of nerve regeneration between sheep and humans. Please see lines 361-364.
Comments 20: Line 260-261 “Porcine are suitable for ultra-long segmental repair (over 15 cm).
Grammar needs improvingby simple includion of the word “models” after “porcine.”
Response 20: Thank you for your suggestion. The grammatical error has been corrected; please refer to line 365.
Comments 21: Lines 265-267 “demonstrating that swine have similar physiology and poly-fascicular nerve architecture..” Improve clarity of sentence by insertion of “to human nerves” before the full stop.
Response 21: Thank you, we have made the suggested modification. Please see line 372.
Comments 22: Lines 267-268 “Notably, the sciatic nerve diameter in large pigs, like the American Yorkshire breed, closely resembles that of human upper extremity PNI [24]” There is an odd disjunction between the beginning and the end of the sentence. Maybe this can be rectified by removing “PNI” and stating which human upper extremity nerves have a similar diameter to the pig sciatic nerve.
Response 22: Thank you, we have made the suggested correction. Please see lines 372-375.
Comments 23: Line 271: Dogs, despite being controversial as household pets . My apologies to the authors for having to be pedantic but dogs are not controversial as household pets!
Response 23: Thank you for the clarification. We agree the original wording was misleading. We have revised the sentence to more accurately reflect ethical concerns related to the use of dogs in research, rather than as household pets. Please see the updated text in lines 392-393.
Comments 24: Lines 275-276: “Attar et al utilized the transected facial nerve in adult female dogs to investigate epineural sutures and fibrin glue [44]”,More detail required about the advantage of choosing this species and nerve for studying epineural sutures and fibrin. Please provide some useful detail about the results of the study.
Response 24: Thank you for the suggestion. We have expanded this section to clarify the rationale for selecting the canine facial nerve as a model and included additional details on the study’s findings. Please see the updated text in lines 382-384.
Comments 25: Lines 284-285: “Cynomolgus monkeys exhibit de-layered delayed nerve regeneration, which extends the study period…” More detail required: delayed in comparison to humans or other monkeys? Which nerves are you referring to in this animal model? What was the rate of axon regeneration in these animals. Was the delay due to an unusually long lag-phase before regeneration started? If so - what caused the lag phase? Extending a study period isn’t, in itself, a negative issue unless the study needs to be substantially extended. Much more detail required.
Response 25: Thank you for highlighting the need for additional detail. We have expanded this section to clarify which nerves were studied, the comparative regeneration rates, the underlying cause of delayed regeneration in non-human primates, and the implications for study design. Please see the updated text in lines 395-410.
Comments 26: Lines 285-286: ”While rhesus monkeys have variable brachial plexus nerve trunks, further limiting their use [27.50].” Again more detail please. Is the variability of the brachial plexus trunks greater than in other primates or humans? Nonetheless, are rhesus monkeys still used for PNI studies? For which nerve injury studies (and why what advantages)?
Response 26: Thank you for the feedback; please see lines 411-420 expanding on the use of rhesus monkeys.
Comments 27: Lines 313-314: “In crush injuries, key structures like the connective tissue, Schwann cell basal lamina, and epineurium are preserved. Shouldn’t the connective tissues of the perineurium also be mentioned here?
Response 27: Thank you for pointing out this omission. We have added ‘perineurium’; please see line 454.
Comments 28: Lines 316-317: “Functional and morphological improvements are generally seen after approximately 21 days post-injury [51].” The authors must state in which species and which nerves and how far the lesion was from the target tissues.
Response 28: Thank you; we have added the suggested details. Please see lines 457-459.
Comments 29: Lines 365--367 “These injuries typically result in slower functional and behavioral recovery, as indicated by histological observations of scar tissue formation and the presence of Büngner bands (basement membrane structures)” In which way would the presence of bands of Büngner indicate slower functional and behavioural recovery?
Response 29: Thank you. We agree that the original statement lacked clarity. We have revised the text to better explain the role of Büngner bands in nerve regeneration and how their degradation correlates with delayed functional and behavioral recovery. Please see the updated text in lines __
Comments 30: Lines 384-385 The chemical model yielded the best results, while clamping and epineurium preservation showed intermediate outcomes. The authors must explain what thye mean by “best results”-and by which criteria/which nerves/which species.
Response 30: Thank you for the suggestions.We have clarified what is meant by "best results" by specifying the outcome measures, species, and nerves involved in the comparative studies. Please see the revised text in lines 508-509.
Comments 31: Line 394-395: “In crush injuries, preserved nerve structures facilitate regeneration, with functional improvements often seen after 21 days.” Meaning ECM? The reader shouldn t have to guess the intended meaning in these sentences.
Response 31: Thank you for the feedback. We clarified that “preserved nerve structures” refers specifically to these components, please see lines 540-545.
Comments 32: Line 400-402 “This may be attributed to preserved vasculature in crush injuries, which supports nerve growth, unlike transection models that require re-establishment of blood vessels[58]. Be clearer in your description here please.The crush injury would surely destroy all cells including vascular endothelial cells at the point of injury so be more precise in your description of what you mean by preserved vasculature.
Response 32: Thank you. We have revised the sentence to be more precise in our description. Please see lines 550-554.
Comments 33: Lines 426-427: ”These findings indicate that medium and tight constrictions (around 14-15%) induce hyperalgesia” Meaning by 14-15% of original diameter or.. to 14-15% of original diameter?
Response 33: Thank you for bringing this to our attention; we mean 14-15% of the original diameter. We have clarified this in lines 578-581.
Comments 34: Lines 465-467 “Research shows that the low-pressure tourniquet results in greater blood perfusion reduction and significantly more tissue swelling compared to femoral artery clamping”. Please clarify how a low pressure tourniquet would lead to greater swelling than a femoral artery clamp.
Response 34: Thank you for your suggestion. Based on the study by Drysch et al., we have clarified the mechanism by which the low-pressure tourniquet produces greater swelling than femoral artery clamping. Please see lines 615-626.
Comments 35: Lines 527-529 “Walking tracks are used to calculate the Sciatic Functional Index (SFI), providing a reliable assessment for crush and transected sciatic nerve injuries in rodents [64,68,69]”. The term “reliable” exaggerates the issue somewhat-it is a good system but weaknesses of the technique have already been raised about assessements based on motor performance. This can be influenced by other parameters - such as muscle contractures or even pain that may develop in the affected limb. The comment on the SFI would be more balanced if such caveats were mentioned.
Response 35: Thank you. We have replaced "reliable" with the more neutral term "general." Please see line 687.
Comments 36: Line 563 “Pain Assessments” do the authors mean, “nociception” or “pain” in this whole section please check and clarify if necessary. Also, the authors should mention which species have been used for such studies, and which rat strains are less prone to developing autophagia.
Response 36: Thank you for your thoughtful comment. We clarified that we are referring to “pain” as a general, multifactorial term encompassing both nociception and neuropathic pain. We have also added species-specific examples for pain assessment techniques and included a note on rat strains with reduced susceptibility to autophagia. Please see revised lines 723-754 and 315-317.
Comments 37: Line 601 “... and Wistar mice s were used in citation #75.
Response 37: Thank you and we apologize for the typo; it has been corrected in line 759.
Comments 38: Line 607-609: “Moreover, aging was associated with decreased c-Jun levels in Schwann cells, NAD depletion affecting mitochondrial function, loss of P/Q type channels, and reduced Schwann cell plasticity [81]..chondrial function, loss of P/Q type channels,.. . Be clearer by stating what type of ion channels these are.
Response 38: Thank you for the suggestion. We have clarified that P/Q-type channels are voltage-gated calcium channels, and revised the sentence accordingly. Please see the updated text in lines 765-768.
Comments 39: Lines 625-626 “..previous sections, ensuring that therapeutic interventions are both effective and translatable to human clinical scenarios.” This is debating since many of the biomaterial and tissue engineering polymers and strategies for PNS repair have been tested in experimental animals but not translated to clinical practice.
Response 39: Thank you. Thank you for the thoughtful feedback. We have revised the sentence to adopt a more neutral tone and acknowledge the current gap between preclinical testing and clinical application. Please see the updated text in lines 782-785.
Comments 40: Line 638-639 ”Merolli et al. demonstrated that conduits facilitated regeneration of myelinated fibers up to 26 mm in a traverse nerve gap injury model [Merolli]” Using which nerve injury model in which species? Inappropriate citation or missing citation. There is also a mention of a Merolli (2022) citation in the Tables that doesn’t appear in the list of references.
Response 40: Thank you for pointing this out. We have clarified the species and nerve model used in the study by Merolli et al., specifying that the work was conducted in New Zealand White rabbits with a traverse sciatic nerve gap. We also confirmed that Merolli et al. (2022) is correctly listed as citation 17. Please see the revised sentence in lines 796-799.
Comments 41: Line 639-641: “This study utilized a large animal model (sheep) to assess the translational potential of nerve conduits, providing valuable insights applicable to human clinical scenarios.” Give examples of which valuable insight you are referring to.
Response 41: Thank you for the suggestion. We amended this sentence and added further detail about the clinical applications of conduits; please see lines 799-808.
Comments 42: Lines 646-647 “Orthodromic and antidromic grafts typically show poorer results than direct nerverepairs[87]”. Explain the terms orthodromic and antidromicgrafts for readers who may not be familiar with the terminology also make it clear that citation #87 is referring to a preclinical study using the tibial nerve of the adult rabbit.
Response 42: Thank you for the feedback. We have defined orthodromic and antidromic grafts and clarified the preclinical nature of the study; please refer to lines 813-818.
Reviewer 4 Report
Comments and Suggestions for Authors
I would like to thank the authors for making all the suggestions.
Comments on the Quality of English Language
Moderate editing.
Author Response
Comments 1: I would like to thank the authors for making all the suggestions. The English could be improved to more clearly express the research
Response 1: Thank you for reviewing our manuscript and providing your feedback, we sincerely appreciate it. We have carefully revised the manuscript and believe we have addressed all grammatical issues. If there are specific sections that still require improvement, we would be grateful for your guidance. Thank you once again.
Round 3
Reviewer 1 Report
Comments and Suggestions for Authors
The revised manuscript has been significantly improved.
