Physiology

Evaluation Summary:

This manuscript examines the importance of PKA-dependent mTORC1 activation for the weight-loss effects of liraglutide. The work has the potential to provide important insights, but at present is deemed preliminary as it lacks details on the mouse model and control data and needs a more in-depth analysis of the metabolic phenotype.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #2 and Reviewer #3 agreed to share their name with the authors.)

Evaluation Summary:

The study is overall well-planned and the amount of data presented by the authors is impressive. The work nicely incorporates animal-level physiology (echocardiography data), tests for known canonical markers of hypertrophy, and then delves into an unbiased analysis of the transcriptome and proteome of LV tissue in bulk. The techniques and analyses in the study are adequately executed and within the realm of expertise of the Lakatta laboratory. This study is a necessary and crucial first step to extensively phenotype this mouse line and generate hypotheses for further work.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 agreed to share their name with the authors.)

Evaluation Summary:

This manuscript is of broad interest to researchers working in the area of lower urinary tract dysfunction. It describes a novel method to reliably study bladder function; the approach allows for monitoring bladder filling and emptying in freely moving, non-anaesthetized animals without the need for catheter implantation. This work has optimized a machine learning algorithm for defining the outline of the urinary bladder border from fluoroscopic images of mice that received subcutaneous injections of iodinated radiocontrast media. The advantage is that with images taken at 30 images/second and with monitoring bladder dynamics requiring hours-long observation periods, this very large number of generated images no longer requires manual analysis.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #1 agreed to share their name with the authors.)

Evaluation Summary:

This manuscript will be of broad interest to the field of muscle biology, muscle physiology, exercise physiology, metabolism and circadian rhythms. This manuscript identifies a new molecular pathway that connects circadian rhythms to muscle structure and function through titin isoform switching.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

The manuscript by Yue et al describes studies investigating the role of sensory neuron versus arteriole expression of Trpv1 in body temperature control. This is a detail about the contribution of different cells which has significance because of the reported on-target side-effect of hyperthermia by Trpv1-antagonists. The study shows that the effects on body temperature are predominantly produced through sensory neurons. From these studies it is speculated that the actions of Trpv1 might be pharmacologically modified to permit dissociation of the effects on neurogenic inflammation and the undesirable effects on body temperature.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. All reviewers agreed to share their names with the authors.)

Evaluation Summary:

This study evaluates the effects of two distinct dietary methods that cause obesity in mice (high fat vs high starch) on insulin sensitivity and glucose homeostasis. Through a series of nicely performed physiology experiments, the authors demonstrated that high starch feeding causes obesity without deleterious effects on insulin sensitivity. This work will have an impact in the field and help define the important lipid mediators of metabolic disease.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #3 agreed to share their name with the authors.)

Evaluation Summary:

Monteiro de Assis et al. demonstrate a role for T3 in modulating circadian metabolic rhythms both systemically and within the liver. The findings extend the molecular framework in which organismal metabolism is coordinated in a circadian fashion.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #2 agreed to share their name with the authors.)

Evaluation Summary:

The authors provide novel evidence that semaphorin signaling (SEMA3F) is engaged in the vascular endothelium and smooth muscle to confer atheroprotection. They show that SEMA3F reduces the activity of key enzyme Phosphoinositide 3-kinase to decrease smooth muscle cell proliferation, migration, and phenotype switching, which contributes to atheroprotection. The study has significant translational potential and yields a new therapeutic target.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. The reviewers remained anonymous to the authors.)

Evaluation Summary:

The authors have used two transgenic mouse models expressing dominant negative Cx43 mutants to evaluate the role of Cx43 hemichannels in mechanical loading response in bone. While understanding the molecular mechanisms by which osteocytes respond to mechanical strain is of interest in the skeletal biology arena, the conclusions of this study are not fully supported by experimental data and are of only incremental in nature.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript.The reviewers remained anonymous to the authors.)

Evaluation Summary:

The study of previously unexplored roles of a cytoskeleton protein termed Septin-7 in muscle could be a significant contribution to understand muscle development and regeneration. The majority of the data support the importance of Septin-7 protein in muscle physiology. With some additional experiments and data analysis to strengthen the mechanistic characterization of Septin-7 in muscle physiology, this manuscript will be of broad interest to readers in the skeletal muscle research field.

(This preprint has been reviewed by eLife. We include the public reviews from the reviewers here; the authors also receive private feedback with suggested changes to the manuscript. Reviewer #2 agreed to share their name with the authors.)