Efficacy and safety of topical minocycline foam (FMX101 4%) in treatment of Chinese subjects with moderate-to-severe facial acne vulgaris: A phase 3, multi-centre, randomized, double-blind, vehicle-controlled study.

BACKGROUND: FMX101 4%, as a topical foam formulation of minocycline, has been approved by US Food and Drug Administration for the treatment of moderate-to-severe acne vulgaris (AV). OBJECTIVE: To evaluate the efficacy and safety of FMX101 4% in treating Chinese subjects with moderate-to-severe facial AV. METHODS: This was a multi-centre, randomized, double-blind, vehicle-controlled phase 3 study in Chinese subjects with moderate-to-severe AV. Eligible subjects were randomized 2:1 to receive either FMX101 4% or vehicle foam treatment for 12 weeks. The primary efficacy endpoint was the change in inflammation lesion count (ILC) from baseline at week 12. The key secondary endpoint was the treatment success rate according to Investigator's Global Assessment (IGA) at week 12. RESULTS: In total, 372 subjects were randomized into two groups (FMX101 4% group, n = 248; vehicle group, n = 124). After 12 weeks treatment, the reduction in ILC from baseline was statistically significant in favour of FMX101 4%, compared with vehicle foam (-21.0 [0.08] vs. -12.3 [1.14]; LSM [SE] difference, -8.7 [1.34]; 95% CI [-11.3, -6.0]; p < 0.001). FMX101 4% treatment yielded significantly higher IGA treatment success rate at week 12 as compared to the control treatment (8.06% vs. 0%). Applying FMX101 4% also resulted in significant reduction in noninflammatory lesion count (nILC) versus vehicle foam at week 12 (-19.4 [1.03] vs. -14.9 [1.47]; LSM [SE] difference, -4.5 [1.74]; 95% CI [-8.0, -1.1]; p = 0.009). Most treatment-emergent adverse events (TEAEs) were mild-to-moderate in severity, and no treatment-related treatment-emergent serious adverse event (TESAE) occurred. Thus, FMX101 4% was considered to be a safe and well-tolerated product during the 12-week treatment period. CONCLUSION: FMX101 4% treatment for 12 weeks could lead to significantly reduced ILC and nILC, and improved IGA treatment success rate in Chinese subjects with moderate-to-severe facial AV. It also showed a well acceptable safe and tolerability profile.

Causal relationship between gut microbiota and pathological scars: a two-sample Mendelian randomization study.

Background: Pathological scars, including keloids and hypertrophic scars, represent a significant dermatological challenge, and emerging evidence suggests a potential role for the gut microbiota in this process. Methods: Utilizing a two-sample Mendelian randomization (MR) methodology, this study meticulously analyzed data from genome-wide association studies (GWASs) relevant to the gut microbiota, keloids, and hypertrophic scars. The integrity and reliability of the results were rigorously evaluated through sensitivity, heterogeneity, pleiotropy, and directionality analyses. Results: By employing inverse variance weighted (IVW) method, our findings revealed a causal influence of five bacterial taxa on keloid formation: class Melainabacteria, class Negativicutes, order Selenomonadales, family XIII, and genus Coprococcus2. Seven gut microbiota have been identified as having causal relationships with hypertrophic scars: class Alphaproteobacteria, family Clostridiaceae1, family Desulfovibrionaceae, genus Eubacterium coprostanoligenes group, genus Eubacterium fissicatena group, genus Erysipelotrichaceae UCG003 and genus Subdoligranulum. Additional sensitivity analyses further validated the robustness of the associations above. Conclusion: Overall, our MR analysis supports the hypothesis that gut microbiota is causally linked to pathological scar formation, providing pivotal insights for future mechanistic and clinical research in this domain.

Intradermal Injection in Balding Region Versus Intramuscular Injection in Surrounding Muscles: A Split-Scalp, Randomized Trial on BoNT for Androgenetic Alopecia.

INTRODUCTION: Recent advancements in androgenetic alopecia (AGA) treatment have highlighted the efficacy of botulinum toxin (BoNT). However, inconsistencies in injection sites and depths warrant attention. It remains unclear which injection strategy is most beneficial for patients. METHODS: This split-scalp randomized controlled trial divided each enrolled participant's scalp along the midline: one side was randomized to receive intramuscular BoNT injections in the surrounding muscles, while the other side received intradermal BoNT injections directly into the balding areas. This study evaluated the impact of treatment on hair density and diameter through trichoscopic examinations conducted at baseline and 12 weeks post treatment. Additionally, assessments of pain and overall safety were integrated into the study protocol. RESULTS: Twenty-nine patients completed the study, with significant improvements in hair density observed in the intramuscular injection group compared to the intradermal group (p < 0.001). Both groups exhibited increases in hair diameter, but no significant difference was found between the two methods (p = 0.433). Pain evaluation revealed that intradermal injections in balding areas were more painful than intramuscular injections (p = 0.036), with no severe adverse reactions reported except for a single case of alopecia areata following injection. CONCLUSION: Our research revealed that both BoNT injection strategies enhanced hair diameter 12 weeks post-treatment, with intramuscular injections significantly improving hair density more effectively. Despite the promising outcomes, the variability in patient responses underscores the necessity for personalized approaches and further research to refine injection protocols for optimized efficacy and safety. TRIAL REGISTRATION NUMBER: ChiCTR2400080190.

A chromosome-level genome assembly of Chinese quince (Pseudocydonia sinensis).

Introduction: Pseudocydonia sinensis, also known as Chinese quince, is a perennial shrub or small tree highly valued for its edibility and medicinal properties. Method: This study presents the first chromosome-level genome assembly of P. sinensis, achieved using HiFi sequencing and Hi-C scaffolding technology. Results: The assembly resulted in a high-quality genome of 576.39 Mb in size. The genome was anchored to 17 pseudo-chromosomes, with a contig N50 of 27.6 Mb and a scaffold N50 of 33.8 Mb. Comprehensive assessment using BUSCO, CEGMA and BWA tools indicates the high completeness and accuracy of the genome assembly. Our analysis identified 116 species-specific genes, 1196 expanded genes and 1109 contracted genes. Additionally, the distribution of 4DTv values suggests that the most recent duplication event occurred before the divergence of P. sinensis from both Chaenomeles pinnatifida and Pyrus pyrifolia. Discussion: The assembly of this high-quality genome provides a valuable platform for the genetic breeding and cultivation of P. sinensis, as well as for the comparison of the genetic complexity of P. sinensis with other important crops in the Rosaceae family.

2% Crisaborole Ointment for the Treatment of Chronic Cheilitis Caused by Lip Tattoos.

The increasing popularity of tattoo art, including facial cosmetic tattoos, has led to a growing societal acceptance of tattoos. However, complications such as lip inflammation following cosmetic lip tattoos remain a concern. This article presents the case of a 47-year-old Asian woman who experienced recurrent lip swelling, purulent discharge, and scarring after receiving lip tattoos. Despite previous treatment with corticosteroid injections yielding unsatisfactory results, the patient showed significant improvement with topical application of 2% Crisaborole, a phosphodiesterase-4 inhibitor. Crisaborole modulates intracellular cyclic adenosine monophosphate levels, thereby reducing tissue inflammation and swelling associated with chronic cheilitis. Additionally, pulse laser therapy was effective in addressing residual tattoo pigment and scar tissue. This case highlights the therapeutic challenges of managing chronic inflammatory diseases of the lips secondary to cosmetic tattoos and introduces Crisaborole as a promising treatment option, offering insights for managing similar conditions in the future.

Fengshi Liuhe Decoction treatment for rheumatoid arthritis via the Fzd6/NF-κB signaling axis.

To explore whether Fengshi Liuhe Decoction (FLD) alleviates rheumatoid arthritis (RA) via the Fzd6/NF-κB signaling axis. We used real-time quantitative PCR (qPCR) and western blotting (WB) to determine the genes of the frizzled (Fzd) protein 1- Fzd protein 10 that are significantly differentially expressed between normal rat fibroblast-like synoviocyte (FLS) and collagen II-induced arthritis (CIA) rat FLS. Next, we used enzyme-linked immunosorbent assay (ELISA) to evaluate the levels of inflammatory factors in cell culture supernatant to determine the ability of FLD to ameliorate RA. Finally, we employed WB to detect the key gene expression in protein levels of the Fzd6/NF-κB signaling axis among normal rat FLS, CIA rat FLS, and FLD-treated CIA rat FLS. Our results showed that Fzd6 expression was significantly higher in CIA rat FLS at both the mRNA and protein levels than in normal rat FLS. FLD was found to downregulate Fzd6 and inflammatory factors, including COX-2, IL-8, and TNF-α, at both the mRNA and protein levels. FLD was also found to downregulate the total protein levels of Fzd6 and the NF-κB signaling pathway key gene phosphorylation of p-p65/p65 and p-IκBα/IκBα. Moreover, FLD inhibited the nuclear translocation of NF-κB p65 in CIA rat FLS. FLD can alleviate inflammation of CIA rat FLS via the Fzd6/NF-κB signaling axis.

Cyanogel-Induced Facile Synthesis of Palladium Hydride for Electrocatalytic Oxygen Reduction.

Palladium hydride (PdHx) is one of the well-known electrocatalytic materials, yet its synthesis is still a challenge through an energy-efficient and straightforward method. Herein, we propose a new and facile cyanogel-assisted synthesis strategy for the preparation of PdH0.649 at a mild environment with NaBH4 as the hydrogen source. Unlike traditional inorganic Pd precursors, the unique Pd-CN-Pd bridge in Pdx[Pd(CN)4]y ⋅ aH2O cyanogel offers more favourable spatial sites for insertion of H atoms. The characteristic three-dimensional backbone of cyanogel also acts as a support scaffold resulting in the interconnected network structure of PdH0.649. Due to the incorporation of H atoms and interconnected network structure, the PdH0.649 achieves a high half-wave potential of 0.932 V, a high onset potential of 1.062 V, and a low activation energy, as well as a long-term lifetime for oxygen reduction reaction. Theoretical calculation demonstrates a downshift of the d-band centre of Pd in PdH0.649 owing to the dominant Pd-H incorporation that weakens the binding energies of the *OH intermediate species. Zn-air batteries (ZAB) based on PdH0.649 exhibits high power density, competitive open circuit voltage, and good stability, exceeding that of commercial Pt black. This work not only opens up a new avenue for the development of high-efficiency Pt-free catalysts but also provides an original approach and insight into the synthesis of PdHx.

Clinical characteristics and outcomes of psoriasis patients with COVID-19: A retrospective, multicenter cohort study in China.

BACKGROUND: Limited information exists regarding the impact of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection on psoriasis patients. The objective of this study was to identify clinical factors associated with the prognosis of psoriasis following SARS-CoV-2 infection. METHODS: A retrospective, multicenter study was conducted between March and May 2023. Univariable and multivariable logistic regression analyses were employed to identify factors associated with COVID-19-related psoriasis outcomes. The study included 2371 psoriasis patients from 12 clinical centers, with 2049 of them having been infected with SARS-CoV-2. RESULTS: Among the infected group, lower exacerbation rates were observed in individuals treated with biologics compared to those receiving traditional systemic or nonsystemic treatments (22.3% [236/1058] vs. 39.8% [92/231] vs. 37.5% [140/373], P <0.001). Psoriasis progression with lesions (adjusted odds ratio [OR] = 8.197, 95% confidence interval [95% CI] = 5.685-11.820, compared to no lesions), hypertension (adjusted OR = 1.582, 95% CI = 1.068-2.343), traditional systemic (adjusted OR = 1.887, 95% CI = 1.263-2.818), and nonsystemic treatment (adjusted OR = 1.602, 95% CI = 1.117-2.297) were found to be associated with exacerbation of psoriasis after SARS-CoV-2 infection, but not biologics (adjusted OR = 0.931, 95% CI = 0.680-1.274, compared to no treatment), according to multivariable logistic regression analysis. CONCLUSIONS: A reduced risk of psoriasis exacerbation after SARS-CoV-2 infection was observed with biologics compared to traditional systemic and nonsystemic treatments. Significant risk factors for exacerbation after infection were identified as existing psoriatic lesions and hypertension. TRIAL REGISTRATION: ClinicalTrials.gov (No. NCT05961605).

Insight into the role of IRF7 in skin and connective tissue diseases.

Interferons (IFNs) are signalling proteins primarily involved in initiating innate immune responses against pathogens and promoting the maturation of immune cells. Interferon Regulatory Factor 7 (IRF7) plays a pivotal role in the IFNs signalling pathway. The activation process of IRF7 is incited by exogenous or abnormal nucleic acids, which is followed by the identification via pattern recognition receptors (PRRs) and the ensuing signalling cascades. Upon activation, IRF7 modulates the expression of both IFNs and inflammatory gene regulation. As a multifunctional transcription factor, IRF7 is mainly expressed in immune cells, yet its presence is also detected in keratinocytes, fibroblasts, and various dermal cell types. In these cells, IRF7 is critical for skin immunity, inflammation, and fibrosis. IRF7 dysregulation may lead to autoimmune and inflammatory skin conditions, including systemic scleroderma (SSc), systemic lupus erythematosus (SLE), Atopic dermatitis (AD) and Psoriasis. This comprehensive review aims to extensively elucidate the role of IRF7 and its signalling pathways in immune cells and keratinocytes, highlighting its significance in skin-related and connective tissue diseases.

Effects of 15% Azelaic Acid Gel in the Management of Post-Inflammatory Erythema and Post-Inflammatory Hyperpigmentation in Acne Vulgaris.

INTRODUCTION: The aim of this study was to assess the efficacy and safety of 15% azelaic acid (AzA) gel in treating acne-induced post-inflammatory erythema (PIE) and post-inflammatory hyperpigmentation (PIH). The effects of 15% AzA gel on acne, skin barrier function, and quality of life were also evaluated. METHODS: A total of 72 patients with mild to moderate acne were enrolled in a randomized, double-blind, placebo-controlled trial. Patients were divided into two groups: patients in the AzA group applied 15% AzA gel twice daily for 12 weeks, and those in the placebo group applied AzA-free gel. Clinical evaluations using non-invasive skin detection technologies, including VISIA skin analysis, dermoscopy, and skin physiological function tests, were performed at 0, 4, 8, and 12 weeks. Main outcome measures included the post-acne hyperpigmentation index (PAHPI), melanin, hemoglobin, individual typology angle, water content, transepidermal water loss, and sebum. Investigator Global Assessment) and Dermatology Life Quality Index (DLQI) assessments were conducted at weeks 0 and 12. Adverse reactions were recorded. RESULTS: Of the 72 patients at study initiation, 60 completed the trial. At 8 and 12 weeks, patients in the AzA group showed significantly reduced PAHPI for PIE lesions compared to baseline and patients receiving placebo (P < 0.05). Patients in both groups exhibited reduced PIH lesions at weeks 8 and 12 that differed significantly from baseline (P < 0.05). Hemoglobin content decreased significantly in AzA-treated PIE lesions compared to those treated with placebo at week 12 (P < 0.05). Melanin content decreased significantly in AzA-treated PIH lesions at week 12 (P < 0.05). The AzA group showed higher improvement in DLQI (P < 0.05), and greater overall satisfaction (P < 0.05) compared to placebo. CONCLUSION: The results indicate that 15% AzA gel effectively improved acne-induced PIE and PIH with minimal adverse reactions, making it a viable clinical application. In the study population, it had no adverse effects on skin barrier function and contributed positively to acne improvement and patient quality of life. TRIAL REGISTRATION: This study was registered with the Chinese Clinical Trial Registry (ChiCTR.org.cn) under the identifier ChiCTR2300076959. The registration date was 25 October 2023, retrospectively registered.

Photodynamic effect of vascular-targeted polyphenol nanoparticles on Endothelial cells.

BACKGROUND: Port wine stains (PWS) are vascular malformations, and photodynamic therapy (PDT) is a promising treatment. Emerging drug delivery methods employ nanoparticles (NPs) to enhance drug permeability and retention in diseased blood vessels and improve drug bioavailability. (-) -epigallocatechin-3-gallate glycine (EGCG) has anti-angiogenetic effects and boosts photodynamic therapy. Chlorin e6 (Ce6) is capable of efficiently producing singlet oxygen, rendering it a very promising photosensitizer for utilization in nanomedicine. MATERIAL AND METHODS: EGCG-Ce6-NPs were synthesized and characterized using various techniques. The photodynamic effects of EGCG-Ce6-NPs on endothelial cells were evaluated. The compatibility and toxicity of the nanoparticle was tested using the CCK-8 assay. The intracellular uptake of the nanoparticle was observed using an inverted fluorescence microscope, and the intracellular fluorescence intensity was detected using flow cytometry. The ROS generation and apoptosis induced by EGCG-Ce6-NPs was observed using confocal laser scanning microscopy and flow cytometry respectively. RESULTS: EGCG-Ce6-NPs exhibited stability, spherical shape of uniform size while reducing the particle diameter, low polydisperse profile and retaining the ability to effectively generate singlet oxygen. These characteristics suggest promising potential for enhancing drug permeability and retention. Additionally, EGCG-Ce6-NPs demonstrated good compatibility with endothelial cells and enhanced intracellular uptake of Ce6. Furthermore, EGCG-Ce6-NPs increased activation efficiency, induced significant toxicity, more reactive oxygen species, and a higher rate of late apoptosis after laser irradiation. CONCLUSION: This in vitro study showed the potentials EGCG-Ce6-NPs for the destruction of endothelial cells in vasculature.

2% supramolecular salicylic acid hydrogel vs. adapaline gel in mild to moderate acne vulgaris treatment: A multicenter, randomized, evaluator-blind, parallel-controlled trial.

OBJECTIVE: Salicylic acid (SA) has been used for treatment of acne of different severity levels. However, there are few researches about the safety and efficacy for treatment of mild to moderate acne, and the improvement of the skin condition by using 2% supramolecular salicylic acid (SSA) compared to Davuwen Adapaline gel. METHODS: A multicenter, randomized, assessor-blind and parallel-controlled study was conducted. A total of 500 patients (trial group: 249, control group: 251) with mild to moderate (grade I-II) facial acne vulgaris were recruited in this study over a 16-week trial period. Patients in the trial group were treated with Broda 2% SSA hydrogel, while control group treated with Davuwen Adapaline gel once a day. The number of inflammatory papules, comedones, and pustules were counted and the rate of lesion reduction was calculated pre- and post-treatment. Then, the skin physiological indicators, including L*a*b*, TEWL, skin sebum and hydration were measured. Statistical analysis was conducted using SAS 9.4. Significance was set at p = 0.05. RESULTS: At the end of 12 weeks' therapy, the regression and markedly improvement rate of the trail group and the control group were 51.01% and 43.10% respectively, and there was no significant difference in the improvement rate between two groups (p = 0.0831). Although, there was no difference in adverse events rate between two groups, the adverse events rate of the trail group was 0.40%, a little lower than the control group (0.80%). Moreover, there was a significant difference in the numbers of pores at T1 between two groups. CONCLUSION: Both 2% SSA and Adapaline gel were equally effective in the treatment of mild to moderate acne vulgaris. 2% SSA is worth the clinical promotion and application in mild to moderate acne vulgaris.

Supramolecular salicylic acid combined with niacinamide in chloasma: A randomized controlled trial.

BACKGROUND: No trial of supramolecular salicylic acid (SSA) for chloasma is available yet. OBJECTIVE: The purpose of this study was to assess the efficacy and safety of Bole DA 30% supramolecular salicylic acid (SSA) combined with 10% niacinamide in treating chloasma. METHODS: This multicenter (n=15), randomized, double-blind, parallel placebo-controlled trial randomized the subjects (1:1) to Bole DA 30% SSA or placebo. The primary endpoint was the effective rate after 16 weeks using the modified melasma area severity index (mMASI) [(pretreatment-posttreatment)/pretreatment×100%]. RESULTS: This study randomized 300 subjects (150/group in the full analysis set, 144 and 147 in the per-protocol set). The total mMASI score, overall Griffiths 10 score, left Griffiths 10 score, and right Griffiths 10 score were significantly lower in the Bole DA 30% SSA group than in the placebo group (all P<0.001). One study drug-related AE and one study drug-unrelated adverse events (AE) were reported in the Bole DA 30% SSA group. No AE was reported in the placebo group. CONCLUSION: Bole DA 30% SSA combined with 10% niacinamide is effective and safe for treating chloasma. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR2200065346.

Asiaticoside alleviates lipopolysaccharide-induced acute lung injury by blocking Sema4D/CD72 and inhibiting mitochondrial dysfunction in RAW264.7 cell and mice.

Acute lung injury (ALI) is a common disease with complex pathogenesis. However, the treatment is mainly symptomatic with limited clinical options. Asiaticoside (AS), a Chinese herbal extract, has protective effects against LPS-induced ALI in mice and inhibits nitric oxide and prostaglandin E2 synthesis; however, the specific mechanism of AS in the prevention and treatment of LPS-induced ALI needs further study. Sema4D/CD72 pathway, mitochondrial dysfunction, and miRNA-21 are closely associated with inflammation. Therefore, the present study aimed to explore whether AS exerts its therapeutic effect on ALI by influencing Sema4D/CD72 pathway and mitochondrial dysfunction, restoring the balance of inflammatory factors, and influencing miRNA-21 expression. Cell and animal experiments were performed to investigate the effect of AS on ALI. Lipopolysaccharide (LPS) was used to establish the ALI model. CCK8 and flow cytometry were used to detect the cell viability and apoptosis rate. HE staining and wet-to-dry weight ratio (W/D) of lung tissue were determined. The expressions of Sema4D, CD72, NF-κB p65, Bax, Bcl2, and caspase 3 in RAW264.7 cells and lung tissues were detected by western blot, and the levels of IL-10 and IL-1ß induced by LPS in supernatant of RAW264.7 cells and BALF were measured by ELISA. And the expression of miRNA-21 in cells and lung tissues was detected by fluorescence quantitative PCR. The result shows that AS treatment suppressed LPS-induced cell damage and lung injury in mice. AS treatment could alleviate the pathological changes such as inflammatory infiltration and histopathological changes in the lungs caused by LPS, and reduce the ratio of W/D. AS significantly alleviated the decrease of mitochondrial membrane potential induced by LPS, inhibited the increase of ROS production, and reduced the expression of mitochondrial fission proteins Drp1 and Fis1. The high-dose AS group significantly downregulated the expression of Sema4D, CD72, phosphorylated NF-κB p65, and apoptosis-related proteins, decreased the pro-inflammatory factor IL-1ß, and enhanced the level of anti-inflammatory factor IL-10. In addition, AS promoted miRNA-21 expression. These effects inhibited apoptosis and restored the balance between anti- and pro-inflammatory factors. This represents the inaugural report elucidating the mechanism by which AS inhibits the Sema4D/CD72 signaling pathway. These findings offer novel insights into the potential application of AS in both preventing and treating ALI.

Visual Interpretation of Radiomics Features in Filtered Computed Tomography Images during the Portal Phase of Acute Pancreatitis.

BACKGROUND: Current research on radiomics for diagnosing and prognosing acute pancreatitis predominantly revolves around model development and testing. However, there is a notable absence of ongoing interpretation and analysis regarding the physical significance of these models and features. Additionally, there is a lack of extensive exploration of visual information within the images. This limitation hinders the broad applicability of radiomics findings. This study aims to address this gap by specifically analyzing filtered Computed Tomography (CT) image features of acute pancreatitis to identify meaningful visual markers in the pancreas and peripancreatic area. METHODS: Numerous filtered CT images were obtained through pyradiomics. The window width and window level were fine-tuned to emphasize the pancreas and peripancreatic regions. Subsequently, the LightGBM algorithm was employed to conduct an embedded feature screening, followed by statistical analysis to identify features with statistical significance (p-value < 0.01). Within the purview of the study, for each filtering method, features of high importance to the preceding prediction model were incorporated into the analysis. The image visual markers were then systematically sought in reverse, and their medical interpretation was undertaken to a certain extent. RESULTS: In Laplacian of Gaussian filtered images within the pancreatic region, severe acute pancreatitis (SAP) exhibited fewer small areas with repetitive greyscale patterns. Conversely, in the peripancreatic region, SAP displayed greater irregularity in both area size and the distribution of greyscale levels. In logarithmic images, SAP demonstrated reduced low greyscale connectivity in the pancreatic region, while showcasing a higher average variation in greyscale between two adjacent pixels in the peripancreatic region. Moreover, in gradient images, SAP presented with decreased repetition of two adjacent pixel greyscales within the pancreatic region, juxtaposed with an increased inhomogeneity in the size of the same greyscale region within the δ range in the peripancreatic region. CONCLUSIONS: Various filtered images convey distinct physical significance and properties. The selection of the appropriate filtered image, contingent upon the characteristics of the Region of Interest (ROI), enables a more comprehensive capture of the heterogeneity of the disease.

Weighted gene co-expression network analysis identifies important modules and hub genes involved in the regulation of breast muscle yield in broilers.

Objective: Increasing breast meat production is one of the primary goals of the broiler industry. Over the past few decades, tremendous progress has been made in genetic selection and the identification of candidate genes for improving the breast muscle mass. However, the molecular network contributing to muscle production traits in chickens still needs to be further illuminated. Methods: A total of 150 1-day-old male 817 broilers were reared in a floor litter system. At the market age of 50 d, eighteen healthy 817 broilers were slaughtered and the left pectoralis major muscle sample from each bird was collected for RNA-seq sequencing. The birds were then plucked and eviscerated and the whole breast muscle was removed and weighed. Breast muscle yield was calculated as the ratio of the breast muscle weight to the eviscerated weight. To identify the co-expression networks and hub genes contributing to breast muscle yield in chickens, we performed weighted gene co-expression network analysis (WGCNA) based on the 18 transcriptome datasets of pectoralis major muscle from eighteen 817 broilers. Results: The WGCNA analysis classified all co-expressed genes in the pectoral muscle of 817 broilers into 44 modules. Among these modules, the turquoise and skyblue3 modules were found to be most significantly positively (r=0.78, p=1e-04) and negatively (r=-0.57, p=0.01) associated with breast meat yield, respectively. Further analysis identified several hub genes (e.g., DLX3, SH3RF2, TPM1, CAV3, MYF6, and CFL2) that involved in muscle structure and muscle development were identified as potential regulators of breast meat production. Conclusion: The present study has advanced our understanding of the molecular regulatory networks contributing to muscle growth and breast muscle production and will contribute to the molecular breeding of chickens in the future.