Dihydrotestosterone (DHT) Enhances Wound Healing of Major Burn Injury by Accelerating Resolution of Inflammation in Mice

Hormonal interventions in skin wounds - a mini review

The ability to heal from wounds is perhaps the most important biological function that ensures our survival and perpetuation. Cutaneous wound healing typically consists of four characteristic stages, namely hemostasis, inflammation, proliferation, and remodeling, which are carefully carried out by coordinated actions of various cells, cytokines, and hormones. Incoordination of these steps may impede complete and efficient reconstruction and functional recovery of wounds or even lead to worsened outcomes. Hormones, as powerful modulators of organ functions, participate in multiple steps of the wound healing process and play a pivotal role by choreographing the complex interplay of cellular and molecular events. Leveraging the regulatory effects of hormones to enhance the healing process, hormonal therapy has emerged as a promising approach in the clinical treatment of wounds. Current research has focused on determination of the optimal dosages, delivery methods, and combinations of hormonal therapies to maximize their therapeutic benefits while minimizing potential side effects. This review highlights the molecular mechanisms, clinical benefits and side effects of the most commonly used hormones in clinical treatment of wounds.

Epigenetic modification: A novel insight into diabetic wound healing

Wound healing is an intricate and fine regulatory process. In diabetic patients, advanced glycation end products (AGEs), excessive reactive oxygen species (ROS), biofilm formation, persistent inflammation, and angiogenesis regression contribute to delayed wound healing. Epigenetics, the fast-moving science in the 21st century, has been up to date and associated with diabetic wound repair. In this review, we go over the functions of epigenetics in diabetic wound repair in retrospect, covering transcriptional and posttranscriptional regulation. Among these, we found that histone modification is widely involved in inflammation and angiogenesis by affecting macrophages and endothelial cells. DNA methylation is involved in factors regulation in wound repair but also affects the differentiation phenotype of cells in hyperglycemia. In addition, noncodingRNA regulation and RNA modification in diabetic wound repair were also generalized. The future prospects for epigenetic applications are discussed in the end. In conclusion, the study suggests that epigenetics is an integral regulatory mechanism in diabetic wound healing.

An androgenetic alopecia remedy based on marine collagen peptide-incorporated dissolving microneedles

Given that current androgenetic alopecia (AGA) medications have adverse effects such as sexual dysfunction and drug dependence, researchers are actively exploring natural bioactive ingredients and innovative approaches (e.g., transdermal drug delivery systems) to effectively combat hair loss with minimal side effects. Herein, we develop a new transdermal drug delivery system incorporating globefish skin collagen peptides with dissolving microneedles (GSCPs-MNs) for hair regrowth. These microneedles generate skin micro-wounds upon application, which not only improves the efficiency of bioactive ingredients delivery, but also stimulates signals involved in hair follicle (HF) regeneration. Our in vivo study shows that minimally invasive implanted GSCPs-MNs are more effective than topical GSCPs in reducing inflammation and promoting collagen formation. Additionally, the upregulation of vascular markers including VEGF and CD31 alongside the downregulation of TNF-α, IL-1β, and malondialdehyde (MDA) index indicate that GSCPs-MNs can significantly alleviate inflammation and oxidation, as well as promoting vascularization and HF functionalization. Overall, our findings suggest that GSCPs-MNs can effectively promote hair regrowth in AGA mice, which offer excellent prospects for the development of new therapeutics and cosmetic supplements for hair loss, along with the combined drug delivery optimization, which could alleviate hair loss in patients with AGA.

Large area fractional laser treatment of mouse skin increases energy expenditure

Fractional laser (FL) treatment is a common dermatologic procedure that generates arrays of microscopic treatment zones separated by intact tissue, promoting fast wound healing. Using a mouse model, we introduced a large area fractional laser treatment (LAFLT) method to study metabolic effects. Using two laser modalities, ablative FL (AFL) and non-ablative FL (NAFL), and exposing different percentages of mice's total body surface area (TBSA), we followed changes in metabolic parameters in real time using metabolic cages. Additionally, body composition, markers of inflammation, neurohormonal signaling, and browning of adipocytes were investigated. LAFLT, especially in high TBSA groups, had specific metabolic effects such as significantly increased average daily energy expenditure, increased fat mass loss, systemic browning of adipocytes, and inflammatory states, without compromising other organs. The ability of LAFLT to stimulate metabolism in a controlled way could develop into a promising therapeutic treatment to induce positive metabolic changes that replace or augment systemic drugs.

The role of cyclins in the development and progression of prostate cancer

The role of cyclins in hormone-dependent neoplasms is crucial in the development of the disease that is resistant to first-line therapy, as the example of breast cancer shows. However, in prostate cancer, cyclins are studied to a lesser extent. There are some well-described molecular pathways, including cyclins A1 and D1 signaling, however the role of other cyclins, e.g., D2, D3, E, and H, still requires further investigation. Recent studies indicate that cyclins regulate various cellular processes, not only the cell cycle. Furthermore, they remain in cross-talk with many other signaling pathways, e.g., MAPK/ERK, PI3K/Akt, and Notch. The androgen signaling axis, which is pivotal in prostate cancer progression, interferes with cyclin pathways at many levels. This article summarizes current knowledge on the influence of cyclins on prostate cancer progression by describing interactions between the androgen receptor and cyclins, as well as mechanisms underlying the development of resistance to currently used therapies.

Controlled dual release of dihydrotestosterone and flutamide from polycaprolactone electrospun scaffolds accelerate burn wound healing

Wound healing is a complex process involving multiple independent and overlapping sequential physiological mechanisms. In addition to cutaneous injury, a severe burn stimulates physiological derangements that induce a systemic hypermetabolic response resulting in impaired wound healing. Topical application of the anti‐androgen drug, flutamide accelerates cutaneous wound healing, whereas paradoxically systemic dihydrotestosterone (DHT) improves burn wound healing. We developed and characterized a PCL scaffold that is capable of controlled release of androgen (DHT) and anti‐androgen (F) individually or together. This study aims to investigate whether local modification of androgen actions has an impact on burn injury wound healing. In a full‐thickness burn wound healing, mouse model, DHT/F‐scaffold showed a significantly faster wound healing compared with F‐scaffold or DHT‐scaffold. Histology analysis confirmed that DHT/F‐scaffold exhibited higher re‐epithelization, cell proliferation, angiogenesis, and collagen deposition. Dual release of DHT and F from PCL scaffolds promoted cell proliferation of human keratinocytes and alters the keratinocyte cell cycle. Lastly, no adverse effects on androgen‐dependent organs, spleen and liver were observed. In conclusion, we demonstrated DHT plus F load PCL scaffolds accelerated burn wound healing when loading alone did not. These findings point to a complex role of androgens in burn wound healing and open novel therapeutic avenues for treating severe burn patients.

Healing Mechanisms in Cutaneous Wounds: Tipping the Balance

Acute and chronic cutaneous wounds pose a significant health and economic burden. Cutaneous wound healing is a complex process that occurs in four distinct, yet overlapping, highly coordinated stages: hemostasis, inflammation, proliferation, and remodeling. Postnatal wound healing is reparative, which can lead to the formation of scar tissue. Regenerative wound healing occurs during fetal development and in restricted postnatal tissues. This process can restore the wound to an uninjured state by producing new skin cells from stem cell reservoirs, resulting in healing with minimal or no scarring. Focusing on the pathophysiology of acute burn wounds, this review highlights reparative and regenerative healing mechanisms (including the role of cells, signaling molecules, and the extracellular matrix) and discusses how components of regenerative healing are being used to drive the development of novel approaches and therapeutics aimed at improving clinical outcomes. Important components of regenerative healing, such as stem cells, growth factors, and decellularized dermal matrices, are all being evaluated to recapitulate more closely the natural regenerative healing process.

Milk and Egg Are Risk Factors for Adverse Effects of Capecitabine-Based Chemotherapy in Chinese Colorectal Cancer Patients

Background:

Chemotherapy-induced adverse effects (CIAEs) remain a challenging problem due to their high incidences and negative impacts on treatment in Chinese colorectal cancer (CRC) patients. We aimed to identify risk factors and predictive markers for CIAEs using food/nutrition data in CRC patients receiving post-operative capecitabine-based chemotherapy.

Methods:

Food/nutrition data from 130 Chinese CRC patients were analyzed. Univariate and multivariate analyses were used to identify CIAE-related food/nutrition factors. Prediction models were constructed based on the combination of these factors. The area under the receiver operating characteristic curve (AUROC) was used to evaluate the discrimination ability of models.

Results:

A total of 20 food/nutrition factors associated with CIAEs were identified in the univariate analysis after adjustments for total energy and potential confounding factors. Based on multivariate analysis, we found that, among these factors, dessert, eggs, poultry, and milk were associated with several CIAEs. Most importantly, poultry was an overall protective factor; milk and egg were risk factors for hand-foot syndrome (HFS) and bone marrow suppression (BMS), respectively. Developed multivariate models in predicting grade 1 to 3 CIAEs and grade 2/3 CIAEs both had good discrimination (AUROC values from 0.671 to 0.778, 0.750 to 0.946 respectively), which had potential clinical application value in the early prediction of CIAEs, especially for more severe CIAEs.

Conclusions:

Our findings suggest that patients with high milk and egg intakes should be clinically instructed to control their corresponding dietary intake to reduce the likelihood of developing HFS and BMS during capecitabine-based chemotherapy, respectively.

Trial registration:

ClinicalTrials.gov Identifier: NCT03030508.

The contradictory role of androgens in cutaneous and major burn wound healing

Wound healing is a complex process involving four overlapping phases: haemostasis, inflammation, cell recruitment and matrix remodeling. In mouse models, surgical, pharmacological and genetic approaches targeting androgen actions in skin have shown that androgens increase interleukin-6 and tumor necrosis factor-α production and reduce wound re-epithelization and matrix deposition, retarding cutaneous wound healing. Similarly, clinical studies have shown that cutaneous wound healing is slower in men compared to women. However, in major burn injury, which triggers not only local wound-healing processes but also systemic hypermetabolism, the role of androgens is poorly understood. Recent studies have claimed that a synthetic androgen, oxandrolone, increases protein synthesis, improves lean body mass and shortens length of hospital stay. However, the possible mechanisms by which oxandrolone regulates major burn injury have not been reported. In this review, we summarize the current findings on the roles of androgens in cutaneous and major burn wound healing, as well as androgens as a potential therapeutic treatment option for patients with major burn injuries.