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Timothy Jee Kam Koh Department of Renal Medicine, Tan Tock Seng Hospital, 308433, Singapore Abstract: Conventional hemodialysis is associated with high morbidity and mortality rates, as well as a reduced quality of life. There is a growing interest in the provision of more intensive hemodialysis, due to associated benefits in terms of reduced cardiovascular morbidity, better regulation of mineral metabolism, as well as its impact on quality of life measures, fertility, and sleep. Nocturnal hemodialysis, both in center and at home, allows the delivery of more intensive hemodialysis. This review discusses the benefits of nocturnal hemodialysis and evaluates the evidence based on available literature. Keywords: nocturnal hemodialysis, quality of life, benefits, outcomes, survival, cardiac

Research articles about the effects of rumen-protected choline (RPC) supplementation on metabolic response, and reproductive and productive performances in transitional dairy cows were reviewed and presented. Analysis was conducted on 32 research papers that were published. The papers examined treatments without RPC supplementation and RPC supplementation levels varying from 10 to 100 gm/day. The feeding duration of RPC started from 40 to 140 days prepartum and continued until 20 to 140 days postpartum in multiparous dairy cows. Studies indicated that adding herbal choline (Cho) to the diet of transition dairy cows resulted in increased milk production and improved milk quality, leading to enhanced energy balance and reduced oxidative stress. The concentration and yield of IgG in colostrum provide passive immunity to dairy newborns and can be enhanced by dietary Cho supplementation. The inconsistent effects of RPC supplementation on reproduction may be due to several factors such as heat stress, genetics, and management. RPC supplementation improved the transition dairy cows' milk yield and quality, but dosage response was not observed as in the prior publication. Remarkably, the length of RPC supplementation had a positive correlation with an increase in milk yield. Based on this review, 45-50 gm/day dietary RPC supplementation between 3 weeks pre-calving to 8 weeks post-calving is suggested to increase at least 10% milk yield in dairy cows., Competing Interests: The authors declare that they have no conflicts of interest., (© The authors.)

This review explores the complex relationship between social determinants of health and the biology of chronic wounds associated with diabetes mellitus, with an emphasis on racial/ethnic disparities. Chronic wounds pose significant healthcare challenges, often leading to severe complications for millions of people in the United States, and disproportionally affect African American, Hispanic, and Native American individuals. Social determinants of health, including economic stability, access to healthcare, education, and environmental conditions, likely influence stress, weathering, and nutrition, collectively shaping vulnerability to chronic diseases, such as obesity and DM, and an elevated risk of chronic wounds and subsequent lower extremity amputations. Here, we review these issues and discuss the urgent need for further research focusing on understanding the mechanisms underlying racial/ethnic disparities in chronic wounds, particularly social deprivation, weathering, and nutrition, to inform interventions to address these disparities., (© 2024 The Author(s). Wound Repair and Regeneration published by Wiley Periodicals LLC on behalf of The Wound Healing Society.)

Monocytes and macrophages (Mos/Mϕs) play diverse roles in wound healing by adopting a spectrum of functional phenotypes; however, the regulation of such heterogeneity remains poorly defined. We enhanced our previously published Bayesian inference TF activity model, incorporating both single-cell RNA sequencing and single-cell ATAC sequencing data to infer transcription factor (TF) activity in Mos/Mϕs during skin wound healing. We found that wound Mos/Mϕs clustered into early-stage Mos/Mϕs, late-stage Mϕs, and APCs, and that each cluster showed differential chromatin accessibility and differential predicted TF activity that did not always correlate with mRNA or protein expression. Network analysis revealed two highly connected large communities involving a total of 19 TFs, highlighting TF cooperation in regulating wound Mos/Mϕs. This analysis also revealed a small community populated by NR4A1 and NFKB1, supporting a proinflammatory link between these TFs. Importantly, we validated a proinflammatory role for NR4A1 activity during wound healing, showing that Nr4a1 knockout mice exhibit decreased inflammatory gene expression in early-stage wound Mos/Mϕs, along with delayed wound re-epithelialization and impaired granulation tissue formation. In summary, our study provides insight into TF activity that regulates Mo/Mϕ heterogeneity during wound healing and provides a rational basis for targeting Mo/Mϕ TF networks to alter phenotypes and improve healing., (Copyright © 2024 by The American Association of Immunologists, Inc.)

Background: (1)Sarcopenia, or low skeletal mass index (SMI), contributes to higher lung cancer mortality. The SMI at third lumbar vertebrae (L3) is the reference standard for body composition analysis. However, there is a need to explore the validity of alternative landmarks in this population. We compared the agreement of sarcopenia identification at the first lumbar (L1) and second lumbar (L2) to L3 in non-Hispanic Black (NHB) and White (NHW) individuals with lung cancer., Methods: (2)This retrospective, cross-sectional study included 214 NHB and NHW adults with lung cancer. CT scans were analyzed to calculate the SMI at L1, L2, and L3. T-tests, chi-square, Pearson's correlation, Cohen's kappa, sensitivity, and specificity analysis were used., Results: (3)Subjects presented with a mean age of 68.4 ± 9.9 years and BMI of 26.3 ± 6.0 kg/m 2 . Sarcopenia prevalence varied from 19.6% at L1 to 39.7% at L3. Cohen's kappa coefficient was 0.46 for L1 and 0.64 for L2, indicating weak and moderate agreement for the identification of sarcopenia compared to L3., Conclusions: (4)Sarcopenia prevalence varied greatly depending on the vertebral landmark used for assessment. Using L2 or L1 alone resulted in a 16.8% and 23.8% misclassification of sarcopenia in this cohort of individuals with lung cancer., Competing Interests: Conflicts of Interest: The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

Obesity is associated with low-grade chronic inflammation and impaired glucose metabolism, both of which are detrimental to wound healing. C-C motif chemokine receptor 2 (CCR2) plays an important role in cell recruitment during healing, and our recent studies revealed the significance of CCR2-CCL2 signaling in promoting the proliferation of pro-inflammatory monocytes/macrophages in wounds. Therefore, we sought to determine whether diet-induced obesity increases monocyte/macrophage proliferation and their accumulation in skin wounds. We first confirmed that wound closure was delayed in obese CCR2 RFP/+ mice fed with a high-fat diet (HFD) compared to mice fed with a normal diet (ND). Using in vivo imaging and flow cytometry analysis, we found that HFD mice had significantly increased accumulation of CCR2+ monocytes/macrophages, particularly pro-inflammatory CCR2+Ly6C+ cells in wounds compared to their ND counterparts. Importantly, HFD mice exhibited an increased proliferation of wound CCR2+Ly6C+ compared to ND mice. Together, our data suggest that obesity leads to an increased proliferation and accumulation of pro-inflammatory CCR2+Ly6C+ monocytes/macrophages in skin wounds, which may contribute to delayed healing.

Monocytes (Mo) and macrophages (Mφ) play important roles in the function of tissues, organs, and systems of all animals during homeostasis, infection, injury, and disease. For decades, conventional wisdom has dictated that Mo and Mφ are end-stage cells that do not proliferate and that Mφ accumulation in tissues is the result of infiltration of Mo from the blood and subsequent differentiation to Mφ. However, reports from the early 1900s to the present describe evidence of Mo and Mφ proliferation in different tissues and contexts. The purpose of this review is to summarize both historical and current evidence for the contribution of Mφ proliferation to their accumulation in different tissues during homeostasis, infection, injury, and disease. Mφ proliferate in different organs and tissues, including skin, peritoneum, lung, heart, aorta, kidney, liver, pancreas, brain, spinal cord, eye, adipose tissue, and uterus, and in different species including mouse, rat, rabbit, and human. Mφ can proliferate at different stages of differentiation with infiltrating Mo-like cells proliferating in certain inflammatory contexts (e.g. skin wounding, kidney injury, bladder and liver infection) and mature resident Mφ proliferating in other inflammatory contexts (e.g. nematode infection, acetaminophen liver injury) and during homeostasis. The pathways involved in stimulating Mφ proliferation also may be context dependent, with different cytokines and transcription factors implicated in different studies. Although Mφ are known to proliferate in health, injury, and disease, much remains to be learned about the regulation of Mφ proliferation in different contexts and its impact on the homeostasis, injury, and repair of different organs and tissues., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of Society for Leukocyte Biology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Significance: Chronic skin wounds are a significant health problem around the world, often leading to amputation and even death. Although persistent inflammation is a hallmark of these poorly healing wounds, few available therapies have been designed to target inflammation. In this review, we summarize available evidence of the role of the NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome in impaired wound healing and describe strategies to inhibit the inflammasome to improve wound healing. Recent Advances: The NLRP3 inflammasome plays an important physiological role in skin wound healing, during which transient inflammasome activity contributes to both epidermal and dermal healing. In contrast, sustained activity of the NLRP3 inflammasome leads to impaired epidermal and dermal healing associated with diabetes. Of importance, preclinical studies have demonstrated that inhibiting the NLRP3 inflammasome-induced resolution of inflammation, increased granulation tissue formation and collagen deposition, and accelerated reepithelialization and wound closure. Critical Issues: NLRP3 inflammasome inhibitors have appealing potential for translation into therapies for chronic wounds. Although preclinical studies have shown promising results, there is a need for human/clinical studies to evaluate dosing formulations, potential therapeutic effects, dose-response relationships, and possible side effects. Future Directions: Among strategies to inhibit the NLRP3 inflammasome, glyburide, metformin, peroxisome proliferator-activated receptor agonists, and the dipeptidyl peptidase 4 inhibitor saxagliptin appear to be closest to clinical translation, as these drugs are already Food and Drug Administration approved for other indications. Future clinical studies are needed to develop topical formulations of these drugs, and to assess the safety and efficacy of these inhibitors, to improve healing of chronic wounds.

Many factors regulate scar formation, which yields a modified extracellular matrix (ECM). Among ECM components, microfibril-associated proteins have been minimally explored in the context of skin wound repair. Microfibril-associated protein 5 (MFAP5), a small 25 kD serine and threonine rich microfibril-associated protein, influences microfibril function and modulates major extracellular signaling pathways. Though known to be associated with fibrosis and angiogenesis in certain pathologies, MFAP5's role in wound healing is unknown. Using a murine model of skin wound repair, we found that MFAP5 is significantly expressed during the proliferative and remodeling phases of healing. Analysis of existing single-cell RNA-sequencing data from mouse skin wounds identified two fibroblast subpopulations as the main expressors of MFAP5 during wound healing. Furthermore, neutralization of MFAP5 in healing mouse wounds decreased collagen deposition and refined angiogenesis without altering wound closure. In vitro, recombinant MFAP5 significantly enhanced dermal fibroblast migration, collagen contractility, and expression of pro-fibrotic genes. Additionally, TGF-ß1 increased MFAP5 expression and production in dermal fibroblasts. Our findings suggest that MFAP5 regulates fibroblast function and influences scar formation in healing wounds. Our work demonstrates a previously undescribed role for MFAP5 and suggests that microfibril-associated proteins may be significant modulators of wound healing outcomes and scarring., (© 2023. The Author(s).)

Chronic wounds in diabetic patients are associated with significant morbidity and mortality; however, few therapies are available to improve healing of diabetic wounds. Our group previously reported that low-intensity vibration (LIV) could improve angiogenesis and wound healing in diabetic mice. The purpose of this study was to begin to elucidate the mechanisms underlying LIV-enhanced healing. We first demonstrate that LIV-enhanced wound healing in db/db mice is associated with increased IGF1 protein levels in liver, blood, and wounds. The increase in insulin-like growth factor (IGF) 1 protein in wounds is associated with increased Igf1 mRNA expression both in liver and wounds, but the increase in protein levels preceded the increase in mRNA expression in wounds. Since our previous study demonstrated that liver was a primary source of IGF1 in skin wounds, we used inducible ablation of IGF1 in the liver of high-fat diet (HFD)-fed mice to determine whether liver IGF1 mediated the effects of LIV on wound healing. We demonstrate that knockdown of IGF1 in liver blunts LIV-induced improvements in wound healing in HFD-fed mice, particularly increased angiogenesis and granulation tissue formation, and inhibits the resolution of inflammation. This and our previous studies indicate that LIV may promote skin wound healing at least in part via crosstalk between the liver and wound. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland., (© 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.)

NK cells are best known for their killing of virus-infected cells and tumor cells via release of cytotoxic factors. However, NK cells can also produce growth factors and cytokines, and thus have the potential to influence physiological processes such as wound healing. In this study, we test the hypothesis that NK cells play a physiological role in skin wound healing of C57BL/6J mice. Immunohistochemical and flow cytometry assays showed that NK cells accumulate in excisional skin wounds, peaking on day 5 postinjury. We also found that NK cells proliferate locally in wounds, and blocking IL-15 activity locally reduces NK cell proliferation and accumulation in wounds. Wound NK cells exhibit primarily a mature CD11b+CD27- and NKG2A+NKG2D- phenotype and express LY49I and proinflammatory cytokines such as IFN-γ, Tnf-a, and Il-1β. Systemic depletion of NK cells resulted in enhanced re-epithelization and collagen deposition, suggesting a negative role for these cells in skin wound healing. Depletion of NK cells did not influence accumulation of neutrophils or monocytes/macrophages in wounds but did reduce expression of IFN-γ, Tnf-a, and Il-1β, indicating that NK cells contribute to proinflammatory cytokine expression in wounds. In short, NK cells may impede physiological wound healing via production of proinflammatory cytokines., (Copyright © 2023 by The American Association of Immunologists, Inc.)

Introduction: Chronic, non-healing skin wounds such as diabetic foot ulcers (DFUs) are common in patients with type 2 diabetes mellitus (T2DM) and often result in limb amputation and even death. However, mechanisms by which T2DM and inflammation negatively impact skin wound healing remains poorly understood. Here we investigate a mechanism by which an excessive level of chemokine CCL28, through its receptor CCR10, impairs wound healing in patients and mice with T2DM. Methods & Results: Firstly, a higher level of CCL28 was observed in skin and plasma in both patients with T2DM, and in obesity-induced type 2 diabetic db/db mice. Compared with WT mice, adipose tissue from db/db mice released 50% more CCL28, as well as 2- to 3-fold more IL-1β, IL-6, and TNF-α, and less VEGF, as determined by ELISA measurements. Secondly, overexpression of CCL28 with adenovirus (Adv-CCL28) caused elevation of proinflammatory cytokines as well as CCR10 expression and also reduced eNOS expression in the dorsal skin of WT mice as compared with control Adv. Thirdly, topical application of neutralizing anti-CCL28 Ab dose-dependently accelerated wound closure and eNOS expression, and decreased IL-6 level, with an optimal dose of 1 μg/wound. In addition, mRNA levels of eNOS and anti-inflammatory cytokine IL-4 were increased as shown by real-time RT-PCR. The interaction between eNOS and CCR10 was significantly reduced in diabetic mouse wounds following application of the optimal dose of anti-CCL28 Ab, and eNOS expression increased. Finally, enhanced VEGF production and increased subdermal vessel density as indicated by CD31 immunostaining were also observed with anti-CCL28 Ab. Discussion: Taken together, topical application of neutralizing anti-CCL28 Ab improved dorsal skin wound healing by reducing CCR10 activation and inflammation in part by preventing eNOS downregulation, increasing VEGF production, and restoring angiogenesis. These results indicate anti-CCL28 Ab has significant potential as a therapeutic strategy for treatment of chronic non-healing diabetic skin wounds such as DFUs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Chen, Haus, DiPietro, Koh and Minshall.)

Background: Lung cancer incidence and mortality rates are higher in Non-Hispanic Black (NHB) compared to Non-Hispanic White (NHW) individuals in the Chicago metropolitan area, which may be related to exposure to chronic stress which may increase inflammation., Specific Aim: We investigated disparities in inflammation as measured by neutrophil to lymphocyte ratio (NLR) in individuals with lung cancer by race and by neighborhood concentrated disadvantage index (CDI)., Methods: This retrospective, cross-sectional study included 263 NHB and NHW adults with lung cancer. We analyzed NLR as a continuous and categorical variable to determine degree and prevalence of inflammation. We used Mann Whitney U, t-tests, Chi square tests, linear and logistic regression models as appropriate., Results: More than 60% of subjects had inflammation (NLR ≥ 3) at lung cancer diagnosis. The degree of inflammation was significantly lower in NHB (NLR 5.50 +/- 7.45) compared to NHW individuals (NLR 6.53 +/- 6.53; p=0.01) but did not differ by neighborhood CDI. The prevalence of inflammation (NLR ≥ 3) was significantly lower in NHB (55.07%) compared to NHW individuals (71.20%; p<0.01) and in those from the most disadvantaged (54.07%) compared to the least disadvantaged (71.88%; p<0.01) neighborhoods., Conclusion: At lung cancer diagnosis, there is a lower degree and prevalence of inflammation in NHB compared to NHW individuals, and lower prevalence in those residing in the most disadvantaged neighborhoods. Further research is needed to determine mechanisms of inflammation that may be contributing to lung cancer disparities as well as whether NLR is an appropriate biomarker when examining racial differences in inflammation., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Byrne, Gomez, Kim, Oddo, Koh and Fantuzzi.)

People with spinal cord injury (SCI) are at high risk of developing a pressure injury. It is unclear why some people with SCI develop pressure injury while others with similar predisposing risk factors do not during acute hospitalisation. This may hinder healthcare utilisation to prevent pressure injuries. The purpose of the study was to examine the proof-of-concept objective bedside skin blood flow measurements before a pressure injury develops in spinal cord injured patients during acute hospitalisation. This was an observational study. All participants had acute traumatic SCI and were pressure injury-free upon enrollment. Skin blood flow patterns were collected at both heels under two circumstances: localised pressure for reactive hyperemia, and localised heating for heat hyperemia. Our results showed that reactive and heat hyperemia were successfully induced in all eleven participants. Two participants developed pressure injury and nine did not have pressure injury at discharge. Heat hyperemia was smaller in participants with pressure injury. No difference was observed in reactive hyperemia between the groups. In conclusion, skin blood flow measurements could be obtained at bedside during acute hospitalisation of SCI for the purpose of research. Further examination of a larger group is warranted to determine clinical use of heat hyperemia pattern as predictor for pressure injury development., (© 2022 The Authors. International Wound Journal published by Medicalhelplines.com Inc (3M) and John Wiley & Sons Ltd.)

Monocytes (Mos)/macrophages (Mϕs) orchestrate biological processes critical for efficient skin wound healing. However, current understanding of skin wound Mo/Mϕ heterogeneity is limited by traditional experimental approaches such as flow cytometry and immunohistochemistry. Therefore, we sought to more fully explore Mo/Mϕ heterogeneity and associated state transitions during the course of excisional skin wound healing in mice using single-cell RNA sequencing. The live CD45+CD11b+Ly6G- cells were isolated from skin wounds of C57BL/6 mice on days 3, 6, and 10 postinjury and captured using the 10x Genomics Chromium platform. A total of 2813 high-quality cells were embedded into a uniform manifold approximation and projection space, and eight clusters of distinctive cell populations were identified. Cluster dissimilarity and differentially expressed gene analysis categorized those clusters into three groups: early-stage/proinflammatory, late-stage/prohealing, and Ag-presenting phenotypes. Signature gene and Gene Ontology analysis of each cluster provided clues about the different functions of the Mo/Mϕ subsets, including inflammation, chemotaxis, biosynthesis, angiogenesis, proliferation, and cell death. Quantitative PCR assays validated characteristics of early- versus late-stage Mos/Mϕs inferred from our single-cell RNA sequencing dataset. Additionally, cell trajectory analysis by pseudotime and RNA velocity and adoptive transfer experiments indicated state transitions between early- and late-state Mos/Mϕs as healing progressed. Finally, we show that the chemokine Ccl7, which was a signature gene for early-stage Mos/Mϕs, preferentially induced the accumulation of proinflammatory Ly6C+F4/80lo/- Mos/Mϕs in mouse skin wounds. In summary, our data demonstrate the complexity of Mo/Mϕ phenotypes, their dynamic behavior, and diverse functions during normal skin wound healing., (Copyright © 2022 by The American Association of Immunologists, Inc.)

Chronic, nonhealing skin wounds, such as diabetic foot ulcers (DFUs), are common in patients with type 2 diabetes. Here, we investigated the role of chemokine (C-C motif) ligand 28 (CCL28) and its receptor C-C chemokine receptor type 10 (CCR10) in downregulation of endothelial nitric (NO) oxide synthase (eNOS) in association with delayed skin wound healing in the db/db mouse model of type 2 diabetes. We observed reduced eNOS expression and elevated CCL28/CCR10 levels in dorsal skin of db/db mice and subdermal leg biopsy specimens from human subjects with type 2 diabetes. Further interrogation revealed that overexpression of CCR10 reduced eNOS expression, NO bioavailability, and tube formation of human dermal microvascular endothelial cells (HDMVECs) in vitro, which was recapitulated in mouse dorsal skin. In addition, incubation of HDMVECs with CCL28 led to internalization of the CCR10/eNOS complex and colocalization with lysosome-associated membrane protein 1. Finally, topical application of myristoylated CCR10 binding domain 7 amino acid (Myr-CBD7) peptide prevented CCR10-eNOS interaction and subsequent eNOS downregulation, enhanced eNOS/NO levels, eNOS/VEGF-R2+ microvessel density, and blood perfusion, reduced inflammatory cytokine levels, and importantly, decreased wound healing time in db/db mice. Thus, endothelial cell CCR10 activation in genetically obese mice with type 2 diabetes promotes eNOS depletion and endothelial dysfunction, and targeted disruption of CCR10/eNOS interaction improves wound healing., (© 2022 by the American Diabetes Association.)

Insulin-like growth factor (IGF)-1 plays important role in tissue repair through its ability to stimulate wound cell activity. While IGF-1 is expressed locally by wound cells, liver-derived IGF-1 is also present at high levels in the circulation, and the contributions of local vs circulating IGF-1 to wound levels remain undefined. The hypothesis of this study was that liver is a primary source of IGF-1 during skin wound healing. To test this hypothesis, we utilized a model that allows inducible ablation of IGF-1 specifically in liver of adult mice. We demonstrate that ablation of liver IGF-1 leads to >85% loss of circulating IGF-1 and ~60% decrease in wound IGF-1 during the proliferative phase of healing in both male and female mice. This reduction of liver-derived IGF-1 did not alter local mRNA expression of Igf1 in wounds. Knockdown of liver IGF-1 significantly delayed wound re-epithelialization and reduced granulation tissue formation and collagen deposition. Knockdown of liver IGF-1 also significantly reduced angiogenesis and resulted in persistent macrophage accumulation. In summary, liver is a primary source of IGF-1 in skin wounds and contributes to many aspects of both epithelial and dermal healing.

Aims: The purpose of this study was to investigate the effect of PPRP (pure PRP) and LPRP (PRP with leukocytes) on recovery from limb ischemia and on expression of growth factors involved in angiogenesis, myogenesis and fibrogenesis., Material and Methods: PPRP and LPRP prepared by centrifugation were added to cultures of C2C12 and NIH3T3 cells (1 or 10% PRPs) to evaluate alterations in cell metabolism and expression of growth factors by MTT, ELISA and RT-qPCR, respectively. To evaluate in vivo regenerative effects, PRPs were injected into the ischemic limbs of BALB/c mice and muscle mass/strength and histomorphometry were evaluated after 30 days., Key Findings: Mice treated with PRPs after limb ischemia showed an increase in the size of myofibers and muscle strength, reduced fibrosis and adipocytes, and decreased capillary density and necrosis scores compared to untreated mice. In cell culture, serum deprivation reduced the viability of C2C12 and NIH3T3 cells to about 50%, but the addition of 1% PRPs completely recovered this loss. Both PRPs, downregulated most of the tested genes; however, angiogenic gene Vegfa in C2C12 and the fibrogenic genes Col1a1 and Col3a1 in NIH3T3 cells were upregulated by LPRP., Significance: PPRP and LPRP had similar effects in regulation of genes involved in angiogenesis, myogenesis and fibrogenesis. However, the presence of leucocytes did not significantly affect regenerative activities of PRP in the ischemic limb., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Monocytes and macrophages (Mo/MΦ) rapidly accumulate in skin wounds after injury, then disappear as healing progresses. However, the mechanisms underlying their ultimate fate in wounds remain to be elucidated. Here, we show that apoptosis of Mo/MΦ parallels their reduction as wound healing progresses in non-diabetic mice. scRNAseq analysis confirmed enriched apoptosis GO pathways on day 6 post-injury in wound Mo/MΦ from non-diabetic mice. In contrast, there was significantly less Mo/MΦ apoptosis in wounds from diabetic mice, particularly in the pro-inflammatory Ly6C+ population, which may contribute to persistent Mo/MΦ accumulation and chronic inflammation. scRNAseq analysis implicated TNF, MAPK, Jak-STAT, and FoxO signaling pathways in promoting wound Mo/MΦ apoptosis in non-diabetic mice while cell proliferation related pathways appeared to be activated in diabetic mice. These novel findings indicate that reduced apoptosis is a contributor to persistent Mo/MΦ accumulation in diabetic wounds. These findings also highlight pathways that may regulate Mo/MΦ apoptosis during wound healing, which could be targeted to help resolve inflammation and improve healing., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Chronic wounds in diabetic patients represent an escalating health problem, leading to significant morbidity and mortality. Our group previously reported that whole body low-intensity vibration (LIV) can improve angiogenesis and wound healing in diabetic mice. The purpose of the current study was to determine whether effects of LIV on wound healing are frequency and/or amplitude dependent. Wound healing was assessed in diabetic (db/db) mice exposed to one of four LIV protocols with different combinations of two acceleration magnitudes (0.3 and 0.6 g) and two frequencies (45 and 90 Hz) or in non-vibration sham controls. The low acceleration, low frequency protocol (0.3 g and 45 Hz) was the only one that improved wound healing, increasing angiogenesis and granulation tissue formation, leading to accelerated re-epithelialization and wound closure. Other protocols had little to no impact on healing with some evidence that 0.6 g accelerations negatively affected wound closure. The 0.3 g, 45 Hz protocol also increased levels of insulin-like growth factor-1 and tended to increase levels of vascular endothelial growth factor in wounds, but had no effect on levels of basic fibroblast growth factor or platelet derived growth factor-bb, indicating that this LIV protocol induces specific growth factors during wound healing. Our findings demonstrate parameter-dependent effects of LIV for improving wound healing that can be exploited for future mechanistic and therapeutic studies., Competing Interests: TK has a patent pending on the application of vibration for therapeutic treatment for tissue repair “Method and system for physical stimulation of tissue” (#2013/0165,824). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Roberts, Bilgen, Kineman and Koh.)

Diabetic wounds are characterized by persistent accumulation of proinflammatory monocytes (Mo)/macrophages (MΦ) and impaired healing. However, the mechanisms underlying the persistent accumulation of Mo/MΦ remain poorly understood. In this study, we report that Ly6C + F4/80 lo/- Mo/MΦ proliferate at higher rates in wounds of diabetic mice compared with nondiabetic mice, leading to greater accumulation of these cells. Unbiased single cell RNA sequencing analysis of combined nondiabetic and diabetic wound Mo/MΦ revealed a cluster, populated primarily by cells from diabetic wounds, for which genes associated with the cell cycle were enriched. In a screen of potential regulators, CCL2 levels were increased in wounds of diabetic mice, and subsequent experiments showed that local CCL2 treatment increased Ly6C + F4/80 lo/- Mo/MΦ proliferation. Importantly, adoptive transfer of mixtures of CCR2 -/- and CCR2 +/+ Ly6C hi Mo indicated that CCL2/CCR2 signaling is required for their proliferation in the wound environment. Together, these data demonstrate a novel role for the CCL2/CCR2 signaling pathway in promoting skin Mo/MΦ proliferation, contributing to persistent accumulation of Mo/MΦ and impaired healing in diabetic mice., (Copyright © 2021 by The American Association of Immunologists, Inc.)

Macrophages are prominent cells in normally healing adult skin wounds, yet their exact functions and functional significance to healing outcomes remain enigmatic. Many functional attributes are ascribed to wound macrophages, including host defense and support of the proliferation of new tissue to replace that lost by injury. Indeed, the depletion of macrophages is unmistakably detrimental to normal skin healing in adult mammals. Yet in certain systems, dermal wounds seem to heal well with limited or even no functional macrophages, creating an apparent paradox regarding the function of this cell in wounds. Recent advances in our understanding of wound macrophage phenotypes, along with new information about cellular plasticity in wounds, may provide some explanation for the apparently contradictory findings and suggest new paradigms regarding macrophage function in wounds. Continued study of this remarkable cell is needed to develop effective therapeutic options to improve healing outcomes.

Background: After traumatic skeletal muscle injury, muscle healing is often incomplete and produces extensive fibrosis. The sequence of M1 and M2 macrophage accumulation and the duration of each subtype in the injured area may help to direct the relative extent of fibrogenesis and myogenesis during healing. We hypothesized that increasing the number of M1 macrophages early after traumatic muscle injury would produce more cellular and molecular substrates for myogenesis and fewer substrates for fibrosis, leading to better muscle healing., Methods: To test this hypothesis, we transfected skeletal muscle with a plasmid vector to transiently express GM-CSF shortly after injury to drive the polarization of macrophages towards the M1 subset. C57BL/6 mouse tibialis anterior (TA) muscles were injured by contusion and electroporated with uP-mGM, which is a plasmid vector that transiently expresses GM-CSF. Myogenesis, angiogenesis, and fibrosis were evaluated by histology, immunohistochemistry, and RT-qPCR; subpopulations of macrophages by flow cytometry; and muscle functioning by the maximum running speed on the treadmill and the recovery of muscle mass., Results: Muscle injury increased the number of local M1-like macrophages and decreased the number of M2-like macrophages on day 4, and uP-mGM treatment enhanced this variation. uP-mGM treatment decreased TGF-β1 protein expression on day 4, and the Sirius Red-positive area decreased from 35.93 ± 15.45% (no treatment) to 2.9% ± 6.5% (p < 0.01) on day 30. uP-mGM electroporation also increased Hgf, Hif1α, and Mtor gene expression; arteriole density; and muscle fiber number during regeneration. The improvement in the quality of the muscle tissue after treatment with uP-mGM affected the increase in the TA muscle mass and the maximum running speed on a treadmill., Conclusion: Collectively, our data show that increasing the number of M1-like macrophages immediately after traumatic muscle injury promotes muscle recovery with less fibrosis, and this can be achieved by the transient expression of GM-CSF.

Monocytes (Mo) and macrophages (Mϕ) play important roles in normal skin wound healing, and dysregulation of wound Mo/Mϕ leads to impaired wound healing in diabetes. Although skin wound Mϕ originate both from tissue resident Mϕ and infiltrating bone marrow-derived Mo, the latter play dominant roles during the inflammatory phase of wound repair. Increased production of bone marrow Mo caused by alterations of hematopoietic stem and progenitor cell (HSPC) niche and epigenetic modifications of HSPCs likely contributes to the enhanced number of wound Mϕ in diabetes. In addition, an impaired transition of diabetic wound Mϕ from "pro-inflammatory" to "pro-healing" phenotypes driven by the local wound environment as well as intrinsic changes in bone marrow Mo is also thought to be partly responsible for impaired diabetic wound healing. The current brief review describes the origin, heterogeneity and function of wound Mϕ during normal skin wound healing followed by discussion of how dysregulated wound Mϕ numbers and phenotype are associated with impaired diabetic wound healing. The review also highlights the possible links between altered bone marrow myelopoiesis and increased Mo production as well as extrinsic and intrinsic factors that drive wound macrophage dysregulation leading to impaired wound healing in diabetes., (Copyright © 2020 Barman and Koh.)

Monocytes and macrophages (Mo/MΦ) play critical roles in all phases of skin wound healing. The majority of these cells are thought to be recruited from blood Mo; however, the role local proliferation of Mo/MΦ in the wound has not been defined. Therefore, we tested the hypothesis that local proliferation of Mo and/or MΦ contributes to their accumulation during wound healing. Male C57Bl/6 mice (N = 4-9/group) were subjected to excisional skin wounding. Proliferating Mo/MΦ (F4/80+Ki67+) were observed in wound cryosections, peaking on day 5 post-wounding. Cell cycle analysis on cells isolated from skin tissue revealed that wounding increased both the number and percentage of inflammatory Ly6C+F4/80lo/- Mo/MΦ in the S/G2/M phases, peaking on day 6 post-wounding. In contrast, more mature Ly6C-F4/80+ cells were found predominantly in the G0 phase with less than 1% cells in S/G2/M phase following injury. In peripheral blood, Mo were very rarely found in the S/G2/M phase, suggesting that the wound environment triggered the Ly6C+F4/80lo/- Mo proliferative response. Furthermore, injury induced several potential regulators of proliferation in wounds, including IL-1β and IL-6, and wound Mo/MΦ expressed surface receptors for these cytokines. However, wound Mo/MΦ proliferation was not altered in IL-1R1 knockout (KO) or IL-6 KO mice. In summary, our findings indicate that proliferation contributes to Mo/MΦ accumulation in wounds and, contrary to findings in other pathophysiologic conditions, Ly6C+/F4/80lo/- Mo/MΦ proliferate during skin wound healing whereas mature Ly6C-F4/80+ MΦ do not., (©2019 Society for Leukocyte Biology.)

Chemokines and their receptors play important roles in vascular homeostasis, development, and angiogenesis. Little is known regarding the molecular signaling mechanisms activated by CCL28 chemokine via its primary receptor CCR10 in endothelial cells (ECs). Here, we test the hypothesis that CCL28/CCR10 signaling plays an important role in regulating skin wound angiogenesis through endothelial nitric oxide synthase (eNOS)-dependent Src, PI3K, and MAPK signaling. We observed nitric oxide (NO) production in human primary ECs stimulated with exogenous CCL28, which also induced direct binding of CCR10 and eNOS resulting in inhibition of eNOS activity. Knockdown of CCR10 with siRNA lead to reduced eNOS expression and tube formation suggesting the involvement of CCR10 in EC angiogenesis. Based on this interaction, we engineered a myristoylated 7 amino acid CCR10-binding domain (Myr-CBD7) peptide and showed that this can block eNOS interaction with CCR10, but not with calmodulin, resulting in upregulation of eNOS activity. Importantly, topical administration of Myr-CBD7 peptide on mouse dermal wounds not only blocked CCR10-eNOS interaction, but also enhanced expression of eNOS, CD31, and IL-4 with reduction of CCL28 and IL-6 levels associated with improved wound healing. These results point to a potential therapeutic strategy to upregulate NO bioavailability, enhance angiogenesis, and improve wound healing by disrupting CCL28-activated CCR10-eNOS interaction., (© 2020 Federation of American Societies for Experimental Biology.)

Recovery from traumatic muscle injuries is typically prolonged and incomplete. Our previous study demonstrated that whole-body low-intensity vibration (LIV) enhances healing in a mouse laceration model. We sought to determine whether locally applied LIV (a) improves muscle repair following injury in mice and (b) is directly transduced by cultured muscle cells, via increased IGF-1 activity. C57BL/6J mice were subjected to laceration of the gastrocnemius muscle and were treated with LIV applied directly to the lower leg for 30 min/day or non-LIV sham treatment (controls) for 7 or 14 days. LIV was also applied to differentiating myotubes in culture for 30 min/day for 3 or 6 days. Compared with control mice, LIV increased myofiber cross-sectional area, diameter, and percent area of peripherally nucleated fibers, and decreased percent damaged area after 14 days of treatment. In cultured myotubes, LIV increased fusion and diameter compared with controls after 6 days of treatment. These LIV-induced effects were associated with increased total Akt on day 7 in injured muscle and on day 3 in myotubes, whereas phosphorylated-to-total Akt ratio increased on day 14 in injured muscle and on day 6 in myotubes but were not associated with increased IGF-1 levels at any time point. These changes were also associated with LIV-induced suppression of FOXO1 and Atrogin-1 gene expression at day 7 in injured muscle. These findings demonstrate that muscle cells can directly transduce LIV signals into increased growth and differentiation, and this effect is associated with increased Akt signaling., (© 2020 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Diabetes induces dysregulation throughout the spectrum of myeloid lineage cells from progenitors to terminally differentiated cells. Another complication of diabetes is persistent inflammation, including prolonged accumulation of macrophages, which contributes to impaired wound healing. However, it remains unclear whether diabetes disrupts the response of bone marrow progenitors to peripheral injury and whether such dysregulation leads to sustained inflammation and impaired healing. Here, we demonstrated that diabetic mice (db/db, referred to here as DB) exhibit myeloid lineage bias during homeostasis and following injury. In addition, cells in the LSK (Lin - Sca-1 + cKit + ) population of DB mice are preprogrammed towards myeloid commitment at the transcriptional level, and cultured myeloid progenitors from DB mice produce more monocytes ex vivo than their non-diabetic counterparts. We also show via bone marrow transfer between interleukin-1 receptor 1 KO (Il1r1 -/- ) and DB mice that IL-1R1 signaling is likely not involved in myeloid skewing in DB mice. Furthermore, in vitro experiments indicated that macrophage colony-stimulating factor receptor signaling is not likely involved in enhanced myeloid transcription factor expression in LSK cells of DB mice. Our findings indicate that myeloid lineage commitment in bone marrow may contribute to increased macrophage numbers observed in diabetic skin wounds, and that strategies to regulate monopoiesis during homeostasis or post-wounding may improve diabetic wound healing. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd., (© 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.)

Background: Cachexia occurs in individuals affected by chronic diseases in which systemic inflammation leads to fatigue, debilitation, decreased physical activity and sarcopenia. The pathogenesis of cachexia-associated sarcopenia is not fully understood., Objectives: The aim of this systematic review is to summarize the current evidence on genes expressed in the skeletal muscles of humans with chronic disease-associated cachexia and/or sarcopenia (cases) compared to controls and to assess the strength of such evidence., Methods: We searched PubMed, EMBASE and CINAHL using three concepts: cachexia/sarcopenia and associated symptoms, gene expression, and skeletal muscle., Results: Eighteen genes were studied in at least three research articles, for a total of 27 articles analyzed in this review. Participants were approximately 60 years of age and majority male; sample size was highly variable. Use of comparison groups, matching criteria, muscle biopsy location, and definitions of cachexia and sarcopenia were not homogenous. None of the studies fulfilled all four criteria used to assess the quality of molecular analysis, with only one study powered on the outcome of gene expression. FOXO1 was the only gene significantly increased in cases versus healthy controls. No study found a significant decrease in expression of genes involved in autophagy, apoptosis or inflammation in cases versus controls. Inconsistent or non-significant findings were reported for genes involved in protein degradation, muscle differentiation/growth, insulin/insulin growth factor-1 or mitochondrial transcription., Conclusion: Currently available evidence on gene expression in the skeletal muscles of humans with chronic disease-associated cachexia and/or sarcopenia is not powered appropriately and is not homogenous; therefore, it is difficult to compare results across studies and diseases., Competing Interests: The authors have declared that no competing interests exist.

Objective: Chronic wounds associated with diabetes are an important public health problem demanding new treatments to improve wound healing and decrease amputations. Monocytes/macrophages play a key role in sustained inflammation associated with impaired healing and local administration of peroxisome proliferator-activated receptor (PPAR)γ agonists may modulate macrophage, improving healing. In this study, we investigated the effects of GQ-11, a partial/dual PPARα/γ agonist, on macrophage function and wound healing in diabetes. Approach: Wounds were surgically induced at the dorsum of C57BL/6J and BKS.Cg-Dock7 m +/+ Lepr db /J (db/db) mice and treated with hydrogel (vehicle), pioglitazone or GQ-11, for 7 or 10 days, respectively. After treatment, wounds were analyzed histologically and by quantitative PCR (qPCR). In addition, bone marrow-derived macrophages (BMDM) were cultured from C57BL/6J mice and treated with vehicle, pioglitazone, or GQ-11, after challenge with lipopolysaccharide or interleukin-4 to be analyzed by qPCR and flow cytometry. Results: GQ-11 treatment upregulated anti-inflammatory/pro-healing factors and downregulated pro-inflammatory factors both in wounds of db/db mice and in BMDM. Innovation: Wounds of db/db mice treated with GQ-11 exhibited faster wound closure and re-epithelization, increased collagen deposition, and less Mac-3 staining compared with vehicle, providing a new approach to treatment of diabetic wound healing to prevent complications. Conclusion: GQ-11 improves wound healing in db/db mice, regulating the expression of pro- and anti-inflammatory cytokines and wound growth factors, leading to increased re-epithelization and collagen deposition., Competing Interests: The authors state no competing financial interests. The content of this article was expressly written by the authors listed. No ghostwriters were used to write this article.

The aim of this study was to determine whether skin wounding induces monocyte (Mo) expansion in bone marrow and whether IL-1R1 signaling regulates this process. Our data show that skin wounding increases myeloid lineage-committed multipotent progenitors (MPP3 subset) and Mo in bone marrow, but this expansion is not impaired in Il1r1 -/- mice. We also demonstrate that M-CSF-induced differentiation of myeloid progenitors into Mo is not impaired by the loss of IL-1R1 ex vivo, indicating that IL-R1 deficiency does not abrogate myeloid progenitor differentiation potential. In addition, we observed modestly delayed wound closure in Il1r1 -/- mice associated with higher frequency of Ly6C lo Mo in the circulation at baseline and in wounds early after injury. Thus, in contrast to other models of inflammation that involve IL-1R1-dependent monopoiesis, our results demonstrate that skin wounding induces Mo progenitor and Mo expansion independently of IL-1R1 signaling., (Copyright © 2019 by The American Association of Immunologists, Inc.)

Ischemic tissue damage activates hematopoietic stem and progenitor cells (HSPCs) in the bone marrow (BM)-generating myeloid cells, and persistent HSPC activity may drive chronic inflammation and impair tissue recovery. Although increased reactive oxygen species in the BM regulate HSPC functions, their roles in myelopoiesis of activated HSPCs and subsequent tissue recovery during ischemic damage are not well understood. In this paper, we report that deletion of Nox2 NADPH oxidase in mice results in persistent elevations in BM HSPC activity and levels of inflammatory monocytes/macrophages in BM and ischemic tissue in a model of hindlimb ischemia. Ischemic tissue damage induces oxidants in BM such as elevations of hydrogen peroxide and oxidized phospholipids, which activate redox-sensitive Lyn kinase in a Nox2-dependent manner. Moreover, during tissue recovery after ischemic injury, this Nox2-ROS-Lyn kinase axis is induced by Nox2 in neutrophils that home to the BM, which inhibits HSPC activity and inflammatory monocyte generation and promotes tissue regeneration after ischemic damage. Thus, oxidant signaling in the BM mediated by Nox2 in neutrophils regulates myelopoiesis of HSPCs to promote regeneration of damaged tissue., (Copyright © 2018 by The American Association of Immunologists, Inc.)

Aim: Investigate the immediate effect of low intensity vibration on skin blood flow and its underlying control mechanisms in healthy human participants., Materials and Methods: One-group pre-post design in a university laboratory setting. Nine adults underwent two bouts of 10-minute vibration (30Hz, peak acceleration 0.4g). Outcome measures include skin blood flow, and skin temperature on the right foot. To examine the control mechanisms underlying the vibration-induced blood flow response, SHORT-TIME Fourier analyses were computed to obtain the spectral densities for three frequency bands: metabolic (0.0095-0.02Hz), neurogenic (0.02-0.06Hz), and myogenic (0.06-0.15Hz). Non-parametric Friedman's tests were computed to compare changes of the outcome measures and control mechanisms over the course of vibration., Results: Vibration increased skin blood flow during both bouts of vibration, however the effect did not last after vibration was terminated. Myogenic spectral density increased during both bouts of vibration, whereas the metabolic and neurogenic spectral densities increased only during the 2nd bout of vibration. Interestingly, only the metabolic spectral density remained elevated after vibration ended., Conclusion: Low intensity vibration produced acute increases in skin blood flow mediated in part by vascular control mechanisms of myogenic origin. Further investigation is warranted to determine whether low intensity vibration induces similar increases in skin blood flow in populations prone to developing chronic non-healing wounds, such as spinal cord injury and diabetes., Competing Interests: The author of this manuscript (Koh) has the following competing interest: patent pending on the application of vibration for therapeutic treatment. The name for the pending patent is, “Method and system for physical stimulation of tissue” (#2013/0165,824). This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Recovery from traumatic muscle injuries is typically prolonged and incomplete, leading to impaired muscle and joint function. We sought to determine whether mechanical stimulation via whole-body low-intensity vibration (LIV) could (1) improve muscle regeneration and (2) reduce muscle fibrosis following traumatic injury. C57BL/6J mice were subjected to a laceration of the gastrocnemius muscle and were treated with LIV (0.2 g at 90 Hz or 0.4 g at 45 Hz for 30 min/day) or non-LIV sham treatment (controls) for seven or 14 days. Muscle regeneration and fibrosis were assessed in hematoxylin and eosin or Masson's trichrome stained muscle cryosections, respectively. Compared to non-LIV control mice, the myofiber cross-sectional area was larger in mice treated with each LIV protocol after 14 days of treatment. Minimum fiber diameter was also larger in mice treated with LIV of 90 Hz/0.2 g after 14 days of treatment. There was also a trend toward a reduction in collagen deposition after 14 days of treatment with 45 Hz/0.4 g ( p = 0.059). These findings suggest that LIV may improve muscle healing by enhancing myofiber growth and reducing fibrosis. The LIV-induced improvements in muscle healing suggest that LIV may represent a novel therapeutic approach for improving the healing of traumatic muscle injuries., Competing Interests: Conflicts of Interest: Timothy J. Koh and Stefan Judex have a patent pending regarding the application of vibrations for therapeutic treatment. Eileen M. Weinheimer-Haus and Thomas F. Corbiere certify that he or she, or a member of his or her immediate family, has no funding or commercial associations (e.g., consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article.

The purpose of this study was to determine whether thrombospondin (TSP)-1 promotes macrophage activity and disease progression in dysferlinopathy. First, we found that levels of TSP-1 are elevated in blood of non-ambulant dysferlinopathy patients compared with ambulant patients and healthy controls, supporting the idea that TSP-1 levels are correlated with disease progression. We then crossed dysferlinopathic BlaJ mice with TSP-1 knockout mice and assessed disease progression longitudinally with magnetic resonance imaging (MRI). In these mice, deletion of TSP-1 ameliorated loss in volume and mass of the moderately affected gluteal muscle but not of the severely affected psoas muscle. T2 MRI parameters revealed that loss of TSP-1 modestly inhibited inflammation only in gluteal muscle of male mice. Histological assessment indicated that deletion of TSP-1 reduced inflammatory cell infiltration of muscle fibers, but only early in disease progression. In addition, flow cytometry analysis revealed that, in males, TSP-1 knockout reduced macrophage infiltration and phagocytic activity, which is consistent with TSP-1-enhanced phagocytosis and pro-inflammatory cytokine induction in cultured macrophages. In summary, TSP-1 appears to play an accessory role in modulating Mp activity in BlaJ mice in a gender, age and muscle-dependent manner, but is unlikely a primary driver of disease progression of dysferlinopathy., (© The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Mounting evidence suggests that therapeutic cell and drug delivery strategies designed to actively harness the regenerative potential of the inflammatory response have great potential in regenerative medicine. In particular, macrophages have emerged as a primary target because of their critical roles in regulating multiple phases of tissue repair through their unique ability to rapidly shift phenotypes. Herein, we review macrophage-based therapies, focusing on the translational potential for cell delivery of ex vivo-activated macrophages and delivery of molecules and biomaterials to modulate accumulation and phenotype of endogenous macrophages. We also review current obstacles to progress in translating basic findings to therapeutic applications, including the need for improved understanding of context-dependent macrophage functions and the myriad factors that regulate macrophage phenotype; potential species-specific differences (e.g. humans versus mice); quality control issues; and the lack of standardized procedures and nomenclature for characterizing macrophages. Looking forward, the inherent plasticity of macrophages represents a daunting challenge for harnessing these cells in regenerative medicine therapies but also great opportunity for improving patient outcomes in a variety of pathological conditions., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Chronic inflammation plays a key role in the pathogenesis of myriad complications associated with diabetes and thus anti-inflammatory therapies may ameliorate these complications. Quercus infectoria (Qi) extract has been shown to downregulate inflammatory processes; however, the molecular mechanisms of this anti-inflammatory activity remain unclear. The hypothesis of our study was that Qi extract exerts its anti-inflammatory effect by downregulating the Set7/NF-κB pathway. Bone marrow-derived macrophages (BMM) were treated with high glucose plus palmitate medium (HG/Pa) to simulate the diabetic environment. Compared with control conditions, HG/Pa elevated expression Set7, expression and activity of NF-κB along with expression of several inflammatory cytokines. These changes were associated with increased levels of intracellular reactive oxygen species (ROS). Moreover, similar alterations were demonstrated in BMM derived from mice fed a high fat diet (HFD) compared to those from lean mice, suggesting that HFD-induced changes in BM progenitors persist throughout differentiation and culture. Importantly, Qi extract dose-dependently reduced Set7, p65 and inflammatory cytokine expression relative to vehicle controls in both HG/Pa-and HFD-treated BMM. Finally, macrophages/monocytes isolated from wounds of diabetic mice that were treated with Qi solution exhibited lower expression of the inflammatory cytokines, IL-1β and TNF-α, compared with vehicle treated wounds, demonstrating translation to the in vivo diabetic environment. Taken together, data from this study suggests that Qi downregulates diabetes-induced activity of the Set7/NF-kB pathway., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Cellular energy is required for the healing cascade to occur. A combination of cells, cytokines, chemokines, tissue perfusion, an extracellular matrix, and local forces are also required to allow for human tissue repair to proceed. Although there are many examples of treatment options, energy-based therapies are the least understood, appreciated, and employed by practicing wound care physicians. The recent growth of tissue engineering has encouraged researchers to employ both electrical stimulation and therapeutic ultrasound (US) to stimulate cells, induce migration, and modify tissue constructs., Methods: The authors have reviewed the literature on electrical stimulation, US, and vibrational therapy and are providing an update to a prior 2007 publication on this topic. The hope was to provide a broad exposure to these treatments but not to create a comprehensive review. A table of evidence was generated from the recent literature to help guide treatment decisions for the clinician., Results: In the current literature, there is much debate over which treatment modality, dosage levels, and timing are optimal. There are numerous in-vitro-based publications that describe mechanism of action and several clinical articles that describe effectiveness of electrical stimulation and US, but few well-controlled and/or randomized trials. The absence of level one evidence has hindered the adoption of these techniques throughout the years. Three energy-based treatment options, electrical stimulation, vibration, and US, will be reviewed along with possible clinical applications, Conclusions: : Although most trials are underpowered with inconsistent treatment settings, physical therapy modality use is increasing in the clinical community. Recent guidelines reference the use of these treatments with increasing evidence level recommendations. At the present time, electrical stimulation carries the greatest level of evidence for clinical use.

Adrenal insufficiency is a complication of chronic corticosteroid therapy. Unexplained hypotension may be a manifestation of an adrenal insufficient state in patients with a history of corticosteroid therapy on hemodialysis. We present a series of five cases of patients on nocturnal home hemodialysis with hypotension as the main manifestation of adrenal insufficiency. Unexplained hypotension in patients with a history of corticosteroid therapy should prompt the managing clinician to consider adrenal insufficiency as a possible cause., (© 2016 International Society for Hemodialysis.)

Properly regulated angiogenesis and arteriogenesis are essential for effective wound healing. Tissue injury induces robust new vessel formation and subsequent vessel maturation, which involves vessel regression and remodeling. Although formation of functional vasculature is essential for healing, alterations in vascular structure over the time course of skin wound healing are not well understood. Here, using high-resolution ex vivo X-ray micro-computed tomography (microCT), we describe the vascular network during healing of skin excisional wounds with highly detailed three-dimensional (3D) reconstructed images and associated quantitative analysis. We found that relative vessel volume, surface area and branching number are significantly decreased in wounds from day 7 to days 14 and 21. Segmentation and skeletonization analysis of selected branches from high-resolution images as small as 2.5μm voxel size show that branching orders are decreased in the wound vessels during healing. In histological analysis, we found that the contrast agent fills mainly arterioles, but not small capillaries nor large veins. In summary, high-resolution microCT revealed dynamic alterations of vessel structures during wound healing. This technique may be useful as a key tool in the study of the formation and regression of wound vessels., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Neuroblastoma is an aggressive, relapse-prone childhood tumor of the sympathetic nervous system. Current treatment modalities do not fully exploit the genetic basis between the different molecular subtypes and little is known about the targets discovered in recent mutational and genetic studies. Neuroblastomas with poor prognosis are often characterized by 1p36 deletion, containing the kinesin gene KIF1B. Its beta isoform, KIF1Bβ, is required for NGF withdrawal-dependent apoptosis, mediated by the induction of XIAP-associated Factor 1 (XAF1). Here, we showed that XAF1 low expression correlates with poor survival and disease status. KIF1Bβ deletion results in loss of XAF1 expression, suggesting that XAF1 is indeed a downstream target of KIF1Bβ. XAF1 silencing protects from NGF withdrawal and from KIF1Bβ-mediated apoptosis. Overexpression of XAF1 impairs tumor progression whereas knockdown of XAF1 promotes tumor growth, suggesting that XAF1 may be a candidate tumor suppressor in neuroblastoma and its associated pathway may be important for developing future interventions., Competing Interests: FINANCIAL SUPPORT AND CONFLICTS OF INTEREST Zhang'e Choo and the project is supported by the National Medical Research Council, Singapore New Investigator Grant awarded to Zhi Xiong Chen. Susanne Schlisio is supported by grants from the Swedish Children Cancer Foundation and the Swedish Research Council. In addition, all authors declare that there is no conflict of interest.

Chronic wounds are a common complication in patients with diabetes that often lead to amputation. These non-healing wounds are described as being stuck in a persistent inflammatory state characterized by accumulation of pro-inflammatory macrophages, cytokines and proteases. Some medications approved for management of type 2 diabetes have demonstrated anti-inflammatory properties independent of their marketed insulinotropic effects and thus have underappreciated potential to promote wound healing. In this review, the potential for insulin, metformin, specific sulfonylureas, thiazolidinediones, and dipeptidyl peptidase-4 inhibitors to promote healing is evaluated by reviewing human and animal studies on inflammation and wound healing. The available evidence indicates that diabetic medications have potential to prevent wounds from becoming arrested in the inflammatory stage of healing and to promote wound healing by downregulating pro-inflammatory cytokines, upregulating growth factors, lowering matrix metalloproteinases, stimulating angiogenesis, and increasing epithelization. However, no clinical recommendations currently exist on the potential for specific diabetic medications to impact healing of chronic wounds. Thus, we encourage further research that may guide physicians on providing personalized diabetes treatments that achieve glycemic goals while promoting healing in patients with chronic wounds., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Macrophages are essential for the efficient healing of various tissues. Although many biochemical signaling pathways have been well characterized in macrophages, their sensitivity to mechanical signals is largely unexplored. Here, we applied low-intensity vibrations (LIV) to macrophages to determine whether macrophages could directly transduce LIV signals into changes in the expression of genes and proteins involved in tissue repair. Two different LIV signal frequencies (30Hz or 100Hz) were combined with two acceleration magnitudes (0.15g or 1g) to generate four distinct LIV signals that were applied to cultured murine macrophages. All four LIV signals significantly increased macrophage number after 3 days of stimulation with the combination of the smallest acceleration and the highest frequency (0.15g at 100Hz) generating the largest response. Compared to non-LIV controls, gene expression of the pro-healing growth factors VEGF and TGF-β increased with all four LIV signals (Day 1). LIV also decreased protein levels of the pro-inflammatory cytokines IL-6, IFN-γ, and TNF-α (Days 1 and 3). These data demonstrate the sensitivity of macrophages to high-frequency oscillations applied at low intensities and may suggest that the benefit of LIV for tissue repair may be based on reducing inflammation and promoting a pro-healing macrophage phenotype., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Dysferlinopathy is associated with accumulation of thrombospondin (TSP)-1 and macrophages, both of which may contribute to the pathogenesis of the disease. The purpose of this study was to determine whether TSP-1 levels can predict macrophage activity and disease progression in dysferlin deficient BlaJ mice, focusing on the early disease process. In 3 month-old BlaJ mice, muscle TSP-1 levels exhibited strong positive correlations with both accumulation of F4/80hi macrophages and with their in vivo phagocytic activity in psoas muscles as measured by magnetic resonance imaging and flow cytometry. Muscle TSP-1 levels also exhibited a strong negative correlation with muscle mass and strong positive correlations with histological measurements of muscle fiber infiltration and regeneration. Over the course of disease progression from 3 to 12 months of age, muscle TSP-1 levels showed more complicated relationships with macrophage activity and an inverse relationship with muscle mass. Importantly, blood TSP-1 levels showed strong correlations with macrophage activity and muscle degeneration, particularly early in disease progression in BlaJ mice. These data indicate that TSP-1 may contribute to a destructive macrophage response in dysferlinopathy and pose the intriguing possibility that TSP-1 levels may serve as a biomarker for disease progression., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Rodent models of healing are considered limited because of the perception that rodent wounds heal by contraction while humans heal by reepithelialization The purpose of this report is to present evidence that simple murine excisional wounds provide a valid and reproducible wound model that heals by both contraction and reepithelialization. Previous studies have shown that, although rodent wounds contract by up to 80%, much of this contraction occurs only after epithelial closure. To confirm these previous findings, we measured re-epithelialization and contraction in three separate mouse strains, (BALB/c, db/+, and db/db); reepithelialization and contraction each accounted for ∼40 to 60% of the initial closure of full thickness excisional wounds. After closure, the wound continues to contract and this provides the impression of dominant closure by contraction. In conclusion, the simple excisional rodent wound model produces a well defined and readily identifiable wound bed over which the process of reepithelialization is clearly measurable., (© 2015 by the Wound Healing Society.)

Background: Uremic neuropathy is a common complication in patients with end stage kidney disease. Its pathogenesis has been attributed to accumulation of uremic toxins. Kidney transplantation has been the best therapeutic option., Case Presentation: We describe a case of severe uremic peripheral neuropathy, which improved after conversion from a conventional renal replacement therapy to nocturnal hemodialysis., Conclusion: Enhanced uremic control by intensive hemodialysis may contribute at least in part to clinical and neurophysiological improvements of uremic neuropathy.

Macrophages undergo a transition from pro-inflammatory to healing-associated phenotypes that is critical for efficient wound healing. However, the regulation of this transition during normal and impaired healing remains to be elucidated. In our studies, the switch in macrophage phenotypes during skin wound healing was associated with up-regulation of the peroxisome proliferator-activated receptor (PPAR)γ and its downstream targets, along with increased mitochondrial content. In the setting of diabetes, up-regulation of PPARγ activity was impaired by sustained expression of IL-1β in both mouse and human wounds. In addition, experiments with myeloid-specific PPARγ knockout mice indicated that loss of PPARγ in macrophages is sufficient to prolong wound inflammation and delay healing. Furthermore, PPARγ agonists promoted a healing-associated macrophage phenotype both in vitro and in vivo, even in the diabetic wound environment. Importantly, topical administration of PPARγ agonists improved healing in diabetic mice, suggesting an appealing strategy for down-regulating inflammation and improving the healing of chronic wounds., (Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.)