Tissue Growth Research Articles

Modelling and simulation of growth driven by mechanical and non-mechanical stimuli

Living tissues can remarkably adapt to their mechanical and biochemical environments through growth and remodelling mechanisms. Over the years, extensive research has been dedicated to understanding and modelling the complexities of growth. However, the majority of growth laws are based on phenomenological, ad hoc, proposed evolution equations. This work aims to describe a general bulk growth model that developed in the framework of generalised continuum mechanics. This new model of growth is based on a continuum description of the growth process and is an extension of the work of DiCarlo and Quiligotti of the early 2000s. This model builds on the virtual power principle, and the constitutive theory is thermodynamically consistent. The proposed framework allows the inclusion of different constitutive theories linking the elastic strain and stresses, together with accommodating different non-mechanical mechanisms. Moreover, the framework supports anisotropy of both the material and growth, allowing the exploration of complex growth processes further. The descriptive capabilities of the model are demonstrated through numerical benchmarks and simulations describing real-life scenarios, such as the growth of the spine and an artery. The simulation results indicate that the developed thermodynamic consistent growth model is versatile and holds the potential to capture the complexities of living tissue growth, offering valuable insights into biological phenomena and pathologies.

Irisflorentin improves functional recovery after spinal cord injury by protecting the blood–spinal cord barrier and promoting axonal growth

Spinal cord injury (SCI) induces the disruption of the blood–spinal cord barrier (BSCB) and the failure of axonal growth. SCI activates a complex series of responses, including cell apoptosis and endoplasmic reticulum (ER) stress. Pericytes play a critical role in maintaining BSCB integrity and facilitating tissue growth and repair. However, the roles of pericytes in SCI and the potential mechanisms underlying the improvements in functional recovery in SCI remain unclear. Recent evidence indicates that irisflorentin exerts neuroprotective effects against Parkinson's disease; however, whether it has potential protective roles in SCI or not is still unknown. In this study, we found that the administration of irisflorentin significantly inhibited pericyte apoptosis, protected BSCB integrity, promoted axonal growth, and ultimately improved locomotion recovery in a rat model of SCI. In vitro, we found that the positive effects of irisflorentin on axonal growth were likely to be mediated by regulating the crosstalk between pericytes and neurons. Furthermore, irisflorentin effectively ameliorated ER stress caused by incubation with thapsigargin (TG) in pericytes. Meanwhile, the protective effect of irisflorentin on BSCB disruption is strongly related to the reduction of pericyte apoptosis via inhibition of ER stress. Collectively, our findings demonstrate that irisflorentin is beneficial for functional recovery after SCI and that pericytes are a valid target of interest for future SCI therapies.

3D-printed Mg-incorporated PCL-based scaffolds improves rotator cuff tendon-bone healing through regulating macrophage polarization.

Introduction: Rotator cuff tear (RCT) is a common shoulder injury impacting mobility and quality of life, while traditional surgeries often result in poor healing. Tissue engineering offers a promising solution, with poly (ε-caprolactone) (PCL) being favored due to its slow degradation, biocompatibility, and non-toxicity. However, PCL lacks sufficient compression resistance. Incorporating Mg, which promotes bone growth and has antibacterial effects, could enhance RCT repair. Methods: The Mg-incorporated PCL-based scaffolds were fabricated using a 3D printing technique. The scaffolds were incorporated with different percentages of Mg (0%, 5%, 10%, 15%, and 20%). The osteogenic activities and anti-inflammatory properties of the scaffolds were evaluated in vitro using human osteoblasts and macrophages. The tissue ingrowth and biocompatibility of the scaffolds were assessed in vivo using a rat model of RCT repair. The ability of the scaffolds to enhance macrophage polarization towards the M2 subtype and inhibit inflammation signaling activation was also investigated. Results: It was found that when incorporated with 10% Mg, PCL-based scaffolds exhibited the optimal bone repairing ability in vitro and in vivo. The in vitro experiments indicated that the successfully constructed 10Mg/PCL scaffolds enhance osteogenic activities and anti-inflammatory properties. Besides, the in vivo studies demonstrated that 10Mg/PCL scaffolds promoted tissue ingrowth and enhanced biocompatibility compared to the control PCL scaffolds. Furthermore, the 10Mg/PCL scaffolds enhanced the macrophages' ability to polarize towards the M2 subtype and inhibited inflammation signaling activation. Discussion: These findings suggest that 3D-printed Mg-incorporated PCL scaffolds have the potential to improve RCT by enhancing osteogenesis, reducing inflammation, and promoting macrophage polarization. The incorporation of 10% Mg into PCL-based scaffolds provided the optimal combination of properties for RCT repair augmentation. This study highlights the potential of tissue engineering approaches in improving the outcomes of RCT repair and provides a foundation for future clinical applications.

Digital light processing printed hydrogel scaffolds with adjustable modulus

Hydrogels are extensively explored as biomaterials for tissue scaffolds, and their controlled fabrication has been the subject of wide investigation. However, the tedious mechanical property adjusting process through formula control hindered their application for diverse tissue scaffolds. To overcome this limitation, we proposed a two-step process to realize simple adjustment of mechanical modulus over a broad range, by combining digital light processing (DLP) and post-processing steps. UV-curable hydrogels (polyacrylamide-alginate) are 3D printed via DLP, with the ability to create complex 3D patterns. Subsequent post-processing with Fe3+ ions bath induces secondary crosslinking of hydrogel scaffolds, tuning the modulus as required through soaking in solutions with different Fe3+ concentrations. This innovative two-step process offers high-precision (10 μm) and broad modulus adjusting capability (15.8–345 kPa), covering a broad range of tissues in the human body. As a practical demonstration, hydrogel scaffolds with tissue-mimicking patterns were printed for cultivating cardiac tissue and vascular scaffolds, which can effectively support tissue growth and induce tissue morphologies.

Leaf gall diversity in the neotropical plant Coccoloba barbadensis (Polygonaceae) and its associated insect species richness

Galls are an abnormal growth of plant tissue in response to the presence generally of an inducing insect, which ensures food and protection during specific periods of its life. Besides gall formers, a vast community of arthropods are associated with galls, including inquilines and parasitoids. Few studies have assessed the gall diversity and its associated insect community in Neotropical vascular plants. Here, we characterised the leaf gall diversity of Coccoloba barbadensis Jacq. (Polygonaceae) in a Mexican tropical dry forest, as well as their associated entomofauna based on morphology and DNA barcoding. Five different gall morphotypes were observed during both dry (April-June) and rainy (November) seasons. A total of 34 and 38 species of Diptera, Hymenoptera, Coleoptera, and Lepidoptera were delimited with the 2% divergence criterion and the GMYC model, respectively. Based on our rearing observations and literature, Cecidomyiidae (Diptera) species might induce all leaf gall morphotypes, whereas hymenopterans are represented by parasitoid and probably inquiline species of the families Braconidae, Eulophidae, Eupelmidae, Platygastridae and Torymidae. Our results highlight the importance of performing integrative species delineation studies of arthropods present in galls to have an accurate knowledge of their diversity and trophic interactions.

Rank Matrix Approach for Endometriosis: Integrating Data and Constructing Diagnostic Models

Background: Endometriosis is a debilitating gynecological disorder characterized by chronic pain, infertility, and the growth of endometrial tissue outside the uterus. Accurate and early detection of this condition is crucial for effective management and treatment. Methods: We developed a gene rank matrix-based model to integrate endometriosis cohorts across multiple platforms. After removing batch effects, we identified 83 genes associated with endometriosis and further refined a diagnostic model using 11 of these genes. The model was trained on two platforms and validated on two others using SVM, Random Forest, Logistic Regression, and gradient-boosting machine learning algorithms. Results: The integration via the gene rank matrix effectively mitigated batch effects. Utilizing a gradient boosting classifier with a subset of 11 genes, the model demonstrated commendable diagnostic efficacy, achieving an Area Under the Curve (AUC) of 0.77, an accuracy of 0.72, and an F1 score of 0.72 for the training dataset. When subjected to validation, the model maintained its performance, yielding an AUC of 0.769, an accuracy of 0.719, and an F1 score of 0.732. These 11 genes were found to be associated with immunosuppression. Conclusion: Our approach to integrating gene rank matrices effectively consolidates endometriosis data across diverse platforms. The diagnostic model, harnessing the predictive power of 11 specific genes, surpasses alternative models, thereby offering promising prospects for aiding clinical diagnosis of endometriosis. Further validation is imperative to elucidate the functional significance of these 11 genes. Our study underscores the potential of data integration coupled with machine learning techniques in advancing the diagnosis of intricate diseases, such as endometriosis.

Evidence from recent clinical trials in fibrotic interstitial lung diseases.

Idiopathic pulmonary fibrosis (IPF) is the prototype of fibrosing interstitial lung diseases. It is mirrored by progressive pulmonary fibrosis (PPF), an umbrella term which characterizes disease behavior of various fibrotic interstitial lung diseases with irreversible progression, accounting for loss of lung function, exercise intolerance and respiratory failure leading to early mortality. Pirfenidone and nintedanib halve the decline in lung function but do not halt disease progression. Since the publication in 2014 of pivotal pirfenidone and nintedanib studies, a number of clinical trials were conducted, many of them did not reach their primary endpoints. In IPF, promising phase 2 trials were followed by large phase 3 trials that did not confirm a favorable efficacy to tolerability favorable profile, including those with ziritaxestat, an autotaxin-1 inhibitor, zinpentraxin-alpha (human recombinant pentraxin-2), and the monoclonal antibody pamrevlumab targeting connective tissue growth factor. Nevertheless, newer compounds that hold promise are currently being evaluated in phase 3 or phase 2b randomized controlled trials, including: nerandomilast, a preferential phosphodiesterase 4B inhibitor; admilparant, a lysophosphatidic acid receptor antagonist; inhaled treprostinil, a prostacyclin agonist; and bexotegrast, a dual-selective inhibitor of αvβ6 and αvβ1 integrins. Nerandomilast, admilparant, inhaled treprostinil, and inhaled AP01 (pirfenidone), are currently studied in patients with PPF. Despite recent frustrating negative results, there is a growing portfolio of candidate drugs developed in both IPF and PPF.

P-332 Decoding autophagy dynamics in adenomyosis: insights of a murine model

Abstract Study question This study aimed to highlight the role of autophagy in the pathogenesis of adenomyosis using a murine model of medically induced adenomyosis. Summary answer Autophagy seems to play a role in the early stages of the disease and is likely not the primary mechanism driving the progression of adenomyosis. What is known already Autophagy is an intracellular mechanism involved in the recycling of aging organelles and non-functional proteins. Initially described as a phenomenon activated under stress or fasting conditions (non-selective autophagy), it is now accepted that a basal level of autophagy is essential for several cellular functions to maintain cellular homeostasis (selective autophagy). Autophagy is essential for cell survival and tissue growth, and an alteration of the autophagic pathway has been described in endometrial pathologies such as endometrial hyperplasia and carcinoma, infertility, and endometriosis. The contribution of autophagy to adenomyosis is still unclear due to conflicting findings in the existing literature. Study design, size, duration This experimental study was conducted from October 2022 until January 2024. A total of 170 mice pups were treated (90 treated with tamoxifen – 80 with vehicle only). Participants/materials, setting, methods Female neonatal CD1 mice received oral doses of 2.7µmol/kg tamoxifen from days 2 to 5 after birth. Control mice received only the vehicle. After synchronizing their estrus cycle, the mice were euthanized at 1 month or 3 months old. The diagnostic and grading of adenomyosis were performed by histological examination (hematoxylin-eosin and immuno-fluorescence). RT-PCR and Western Blot were used to study the modulation of autophagy pathways between the uterus of the two groups. Main results and the role of chance Histological analysis of 3-month-old tamoxifen-treated group showed that 97% of the mice developed the disease. The grading method was defined by assessing the depth of lesions. After sensitivity enhancement through immunofluorescence staining (alpha-SMA, EpCAM and DAPI), grade 3 adenomyosis was diagnosed in up to 91% of our samples (vs 84% when analyzed by H&E only). Neonatal treatment of CD1 mice with tamoxifen reliably produces severe adenomyotic lesions. Immunofluorescence enhances sensitivity in histological examinations of myometrial lesions, combining alpha-SMA staining for smooth muscle detection with EpCAM for identifying epithelial cells. RTqPCR analysis of lc3b, akt, bcl2, bclxl, ulk2, ulk1, cxcr4, tnfs10, dapk1, igf1, atg9, pik3c3, and bid showed an up-regulation of autophagy in one-month-old adenomyosis mice. This was also indicated by a decrease in akt and bcl2, which are inhibitors of the pathway, along with an increase in lc3b, a marker for phagophore formation. However, the conflicting decrease in ulk2, a component of the induction complex, raises questions. Importantly, these changes in autophagy are not observed in 3-month-old mice, suggesting that autophagy may play a role in the early stages of disease development. There were no statistical differences in Protein expression of pakt/akt, lc3b, and bcl2 between the groups. Limitations, reasons for caution The analysis used protein or mRNA extracted from the whole uterus. Variations in results may arise if the endometrial and myometrial components are analyzed separately. Techniques like laser capture microdissection could prove valuable in this context. Continued research focusing on investigating the role of apoptosis in the study is essential. Wider implications of the findings Given the frequent association of adenomyosis with endometriosis and/or uterine fibroids, using an experimental model offers the advantage of eliminating bias from associated comorbidities. This approach presents a unique opportunity to unravel the molecular basis of adenomyosis, while enabling a translational analysis when juxtaposed with clinical studies. Trial registration number not applicable

P-291 In women with endometriosis, effective treatment of chronic endometritis with antibiotics lowers serum CA-125 levels

Abstract Study question To evaluate the effect of chronic endometritis treatment on serum CA-125 levels in women with endometriosis. Summary answer Cure of chronic endometritis leads to a reduction in serum Ca-125 levels in women with endometriosis. What is known already Endometriosis is a chronic inflammatory disease characterized by the ectopic growth of endometrial tissue outside the uterine cavity. It is hypothesized that the disease exerts direct inflammatory effects on the ovaries, fallopian tubes, and the eutopic endometrium. In endometriosis, CA-125 levels are often elevated. Literature reports a frequent coexistence of endometriosis and chronic endometritis (CE) in women undergoing hysterectomy for benign indications. CE, characterized by macroscopic and histological alterations of the endometrium, was present in 38.5%-42.3% of women with endometriosis, compared to lower prevalence rates in controls infertile patients without endometriosis, supporting a potential etiopathogenic link between endometriosis and CE. Study design, size, duration This retrospective case-control study was conducted at the Department of Obstetrics and Gynecology, University of Bari. The study included 51 patients suffering of both ovarian endometriosis and CE. The primary objective was to investigate whether CE cure modifies serum CA-125 levels among women with ovarian endometriosis. The secondary objective was to assess any modifications in the size of endometriotic cysts following the cure of CE. Recruitment period was from September 2021 to February 2023. Participants/materials, setting, methods All patients received antibiotic therapy (100 mg of doxycycline, twice daily for ten days) and, the following month, hysteroscopy with control biopsy. Of these, 36 women were cured of chronic endometritis (Group A), while 15 women showed persistent disease (Group B). Endometriosis was diagnosed by transvaginal ultrasound and chronic endometritis through hysteroscopy, histology, and immunohistochemistry for CD138. Serum CA-125 levels were measured before antibiotic therapy and approximately 3 months later. Main results and the role of chance The primary outcome was to compare the change in CA-125 values between women cured of chronic endometritis and women with persistent disease. There were no statistically significant differences in baseline characteristics between the groups (p=ns). The majority of patients in both groups had a single ovarian endometrioma and the micropolypoid endometrial appearance was the predominant finding of chronic endometritis observed during hysteroscopy in both Groups. In Group A, the mean CA-125 value significantly decreased after antibiotic therapy from 58.56 U/mL (± 32.45) to 38.25 U/mL (± 17.31) (p < 0.001). No significant changes in CA-125 values were observed in Group B before and after antibiotic therapy (69.70 ± 27.42 versus 67.47 ± 24.52 U/mL, p=ns). The absolute change in CA-125 values was significantly greater in terms of reduction in Group A compared to Group B (-20.31 ± 27.09 versus -2.13 ± 12.51 U/mL; p = 0.02). Adjustment for confounders in a multivariable regression model revealed that the cure of chronic endometritis was independently associated with a significant decrease in absolute serum CA-125 levels (p = 0.006). Cyst size did not significantly change after antibiotic therapy in both groups (p=ns). Limitations, reasons for caution The main weakness of our study is that CA-125 was only measured once before and once after treatment of CE with a course of antibiotics. Moreover, our study does not allow for inferences regarding the impact of the observed reduction in serum CA-125 on the subjective symptoms related to endometriosis. Wider implications of the findings Our study constitutes the first demonstration that effective treatment of CE results in a significant decrease in a non-invasive marker of endometriosis, CA-125 supporting the emerging concept that the endometriosis might have an infectious origin. Trial registration number not applicable

P-309 Injectable “homing-like” bioactive short-fibers for endometrial repair and efficient live births

Abstract Study question To develop effective therapeutic interventions to promote endometrial growth and facilitate the restoration of the damaged endometrium of rats with intrauterine adhesion (IUA). Summary answer We have developed injectable “homing-like” bioactive decellularized extracellular matrix short-fibers which can achieve efficient endometrial repair and live births of rats with IUA. What is known already The prevalence of infertility caused by endometrial defects has been steadily increasing, posing a significant challenge to women’s reproductive health. Various factors, such as infection and intrauterine surgery, can lead to damage to the basal layer of the endometrium, which hinders functional endometrial repair and results in the pathological development of IUA. However, there is currently no effective clinical treatment strategy for IUA. Therefore, it is imperative to develop effective therapeutic interventions to promote endometrial growth and receptivity, ameliorate endometrial fibrosis, and facilitate the restoration of the damaged endometrium that ultimately reverses the poor pregnancy outcomes of patients with IUA. Study design, size, duration We have developed an innovative method for creating injectable acellular extracellular matrix short fibers (DEFs) from porcine skin. We investigated the effects of DEFs by in vitro and in vivo experiments over a period of two years. Participants/materials, setting, methods In vitro, we investigated the pro-proliferative, anti-fibrosis and angiogenesis effects of DEFs in human primary endometrial stromal cells (HESCs) and human umbilical vein endothelial cells (HUVECs). In vivo, we constructed a rat IUA model to investigate the promotion of endometrial repair and fertility remodeling by DFEs. Main results and the role of chance The DEFs can effectively attract endometrial cells, enabling cell adhesion, spreading, and proliferation on their surface. DEFs are rich in bioactive growth factors, which creates a nourishing microenvironment for endometrial recovery while attracting and recruiting endogenous endometrial cells for in situ regeneration. Initially, DEFs formed stable bonds with the surface of endometrial cells via electrostatic interactions after injection into the uterine cavity, which acted as a physical barrier to prevent intrauterine adhesions. Subsequently, DEFs effectively facilitated the proliferation and angiogenesis of HESCs and HUVECs, and inhibited fibrosis of pretreated HESCs. Next, DEFs could decrease endometrial collagen deposition and promote endometrial repair and endometrial angiogenesis by releasing growth factors. Therefore, bioactive DEFs could efficiently improve endometrial receptivity, promote endometrial repair, and achieve efficient live births in endometrium-injured rats. Limitations, reasons for caution The composition of DEFs is complex. The mechanism by which DEFs promotes endometrial repair remains unclear. In our future endeavors, our primary aim is to conduct a proteomic analysis of the DEFs to pinpoint the vital proteins responsible for their ability to induce tissue growth. Wider implications of the findings The DEFs can achieve efficient live births and the preparation method is suitable for mass production. In addition, the injectability of DEFs can achieve non-invasive intrauterine injection, which can reduce the risk of endometrial re-injury. Therefore, the DEFs system provides a new promising clinical strategy for endometrial factor infertility. Trial registration number enter ‘not applicable

Regulating Tissue Growth Factors for Healing with Etherified Carboxymethylcellulose Matrix.

Etherified Carboxymethylcellulose Matrix (eCMC) is a revolutionary application of carboxymethylcellulose (CMC) in wound care, known for its potential in hemostasis and tissue regeneration. This study aims to investigate the mechanism of eCMC in tissue healing by establishing a rat burn model and administering eCMC as a treatment. The objective is to analyze cytokines and inflammatory mediators using a Cytokine Array and histochemical staining to understand the effects of eCMC on tissue regeneration. A rat burn model was created, and eCMC was applied as a treatment. Tissue samples were collected at multiple time points to assess the expression of cytokines and inflammatory mediators using a Cytokine Array. Additionally, histochemical staining was performed to evaluate tissue regeneration factors. eCMC induced the expression of endogenous cytokines, particularly VEGF and PDGF, while inhibiting inflammatory cytokines such as CINC-1, CINC-2, and MMP-8. This dual action facilitated wound healing and mitigated the risk of infection. eCMC demonstrates promising potential for enhancing skin regeneration. Further research is warranted to delve into the precise mechanism of eCMC's cytokine regulation. In vitro and in vivo studies should be conducted to comprehensively investigate the therapeutic capabilities of eCMC in wound healing.

Mechanical stress-induced connective tissue growth factor plays a critical role in intestinal fibrosis in Crohn's-like colitis.

Crohn's disease (CD) is an inflammatory bowel disease characterized by transmural inflammation and intestinal fibrosis. Mechanisms of fibrosis in CD are not well understood. Transmural inflammation is associated with inflammatory cell infiltration, stenosis, and distention, which present mechanical stress (MS) to the bowel wall. We hypothesize that MS induces gene expression of profibrotic mediators such as connective tissue growth factor (CTGF), which may contribute to fibrosis in CD. A rodent model of CD was induced by intracolonic instillation of TNBS to the distal colon. TNBS instillation induced a localized transmural inflammation (site I), with a distended colon segment (site P) proximal to site I. We detected significant fibrosis and collagen content not only in site I but also in site P in CD rats by day 7. CTGF expression increased significantly in sites P and I, but not in the segment distal to the inflammation site. Increased CTGF expression was detected mainly in the smooth muscle cells (SMCs). When rats were fed exclusively with clear liquid diet to prevent mechanical distention in colitis, expression of CTGF in sites P and I was blocked. Direct stretch led to robust expression of CTGF in colonic SMC. Treatment of CD rats with anti-CTGF antibody FG-3149 reduced fibrosis and collagen content in both sites P and I and exhibited consistent trends toward normalizing expression of collagen mRNAs. In conclusion, our studies suggest that mechanical stress, by upregulating profibrotic mediators, i.e., CTGF, may play a critical role in fibrosis in CD.NEW & NOTEWORTHY We found that CTGF expression increased significantly not only in the inflammation site but in the distended segment proximal to inflammation in a rodent model of CD-like colitis. Release of mechanical distention prevented CTGF expression in CD rats, whereas direct stretch induced CTGF expression. Treatment with anti-CTGF antibody reduced fibrosis and collagen contents in CD rats. Thus, mechanical stress, via upregulating profibrotic mediators, i.e., CTGF, may play a critical role in fibrosis in CD.

Bioelectronic Delivery of Potassium Ions Controls Membrane Voltage and Growth Dynamics in Bacteria Biofilms

AbstractBioelectrical signaling, or bioelectricity, is crucial in regulating cellular behavior in biological systems. This signaling, involving ion fluxes and changes in membrane potential (Vmem), is particularly important in the growth of bacterial biofilm. Current microfluidic-based methods for studying bacterial colonies are limited in achieving spatiotemporal control over ionic fluxes due to constant flow within the system. To address this limitation, we have developed a platform that integrates biofilm colonies with bioelectronic ion pumps that enable delivery of potassium (K+) ions, allowing for controlled manipulation of local potassium concentration. Our study examines the impact of controlled K+ delivery on bacterial biofilm growth patterns and dynamics. We observed significant changes in Vmem and coordination within the biofilms. Furthermore, we show that localized K + delivery is highly effective in controlling biofilm expansion in a spatially targeted manner. These findings offer insights into the mechanisms underlying bacterial signaling and growth, and suggest potential applications in bioengineering, synthetic biology, and regenerative medicine, where precise control over cellular signaling and subsequent tissue growth is required.

NEDD8 enhances Hippo signaling by mediating YAP1 neddylation

The Hippo-YAP signaling pathway plays a central role in many biological processes such as regulating cell fate, organ size and tissue growth, and its key components are spatiotemporally expressed and post-translationally modified during these processes. Neddylation is a post-translational modification that involves the covalent attachment of NEDD8 to target proteins by NEDD8-specific E1-E2-E3 enzymes. Whether neddylation is involved in Hippo-YAP signaling remains poorly understood. Here, we provide evidence supporting the critical role of NEDD8 in facilitating the Hippo-YAP signaling pathway by mediating neddylation of the transcriptional coactivator Yes-associated protein 1 (YAP1). Overexpression of NEDD8 induces YAP1 neddylation and enhances YAP1 transactivity, but inhibition of neddylation suppresses YAP1 transactivity and attenuates YAP1 nuclear accumulation. Furthermore, inhibition of YAP1 signaling promotes MLN4924-induced GCs apoptosis and disruption of nedd8 in zebrafish results in downregulation of yap1-activated genes and upregulation of yap1-repressed genes. Further assays show that the xiap ligase promotes nedd8 conjugates to yap1 and that yap1 neddylation. In addition, we identify lysine 159 as a major neddylation site on YAP1. These findings reveal a novel mechanism for neddylation in the regulation of Hippo-YAP signaling.

Unravelling the therapeutic potential of forkhead box proteins in breast cancer: An update (Review).

Breast cancer, a prominent cause of mortality among women, develops from abnormal growth of breast tissue, thereby rendering it one of the most commonly detected cancers in the female population. Although numerous treatment strategies are available for breast cancer, discordance in terms of effective treatment and response still exists. Recently, the potential of signaling pathways and transcription factors has gained substantial attention in the cancer community; therefore, understanding their role will assist researchers in comprehending the onset and advancement of breast cancer. Forkhead box (FOX) proteins, which are important transcription factors, are considered crucial regulators of various cellular activities, including cell division and proliferation. The present study explored several subclasses of FOX proteins and their possible role in breast carcinogenesis, followed by the interaction between microRNA (miRNA) and FOX proteins. This interaction is implicated in promoting cell infiltration into surrounding tissues, ultimately leading to metastasis. The various roles that FOX proteins play in breast cancer development, their intricate relationships with miRNA, and their involvement in therapeutic resistance highlight the complexity of breast cancer dynamics. Therefore, recognizing the progress and challenges in current treatments is crucial because, despite advancements, persistent disparities in treatment effectiveness underscore the need for ongoing research, with future studies emphasizing the necessity for targeted strategies that account for the multifaceted aspects of breast cancer.

Gut Microbiota Disorder Contributes to the Production of IL-17A That Exerts Chemotaxis via Binding to IL-17RA in Endometriosis.

Endometriosis (EM) is a chronic estrogen-dependent condition characterized by the growth of endometrial-like tissue outside the uterus, posing a significant burden on reproductive-aged women. Previous research has shown a correlation between gut microbiota dysbiosis and interleukin-17A (IL-17A) in EM patients. IL-17A, a promising immunomodulatory molecule, exerts dual roles in human physiology, driving inflammatory diseases. However, the functions and origins of IL-17A in EM remain poorly characterized. Single-cell data analysis was employed to characterize IL-17A activity in EM lesions. Fecal microbiota transplantation was conducted to explore the impact of gut microbiota on EM. Gut microbiota and bile acid metabolism were assessed via 16S rRNA sequencing and targeted metabolomics. Th17 cell proportions were measured using flow cytometry. High expression of IL-17 receptor A (IL-17RA) was observed in myeloid cell subpopulations within EM lesions and may be involved in the migration and recruitment of inflammatory cells in lesions. Elevated IL-17A levels were further validated in peritoneal and follicular fluids of EM patients. Dysregulated bile acid levels, particularly elevated chenodeoxycholic acid (CDCA) and ursodeoxycholic acid (UDCA), were found in the gut and peritoneal fluid of EM mouse models. Additional CDCA administration reduced EM lesions and modulated Th17 cell proportions, while UDCA showed no significant effects. Our findings shed light on the origins and functions of IL-17A in EM, implicating its involvement in lesion migration and recruitment. Dysregulated bile acid metabolism may contribute to EM pathogenesis, with CDCA exhibiting therapeutic potential.

A Novel Use of Embryonic Gut Organoid Culture to Investigate Duodenal Atresia

BackgroundThe cause of duodenal atresia (DA) is not known. Tandler's “solid cord” hypothesis conflicts with current biological evidence. In humans, a genetic aetiology is supported by the association with Trisomy 21. Interruption of Fgf10 is the strongest genetic link to DA in mice, demonstrating an increased incidence and severity as embryos mature. This project aimed to develop an organoid model to facilitate ex vivo DA research on the FGF10/FGFR2b signalling pathway. We hypothesised that DA morphology represents an evolving spectrum of disease and that Fgf10 knockout organoids would vary in growth pattern compared to wild-type. MethodsOrganoids were cultured from the duodenum of E12.5 Fgf10 knockout, heterozygous and wild-type embryos, using an air-liquid interface with Growth Factor reduced Matrigel. Organoids were photographed every 48 h to observe growth. Organoids were isolated and fixed after 14 days, then stained with DAPI, KI-67, and cytokeratin to demonstrate proliferation and differentiation. ResultsWild-type duodenum developed into crypt-forming organoids. Fgf10 heterozygous duodenum failed to progress beyond the development stage of spheroids. Fgf10 knockout duodenum failed to demonstrate any growth. Wholemount staining showed the greatest cell proliferation and differentiation in wild-type tissue. ConclusionThis research presents a novel concept for the growth of embryonic gastrointestinal tissue to inform normal biology. The small sample numbers and restricted culture duration limit longer-term growth analysis. While this model serves as a potential ex vivo setting for future research, that research should consider organoid models with greater standardisation and other gastrointestinal regions. Level of EvidenceAnimal/laboratory study.

Incorporation of decellularized-ECM in graphene-based scaffolds enhances axonal outgrowth and branching in neuro-muscular co-cultures.

Peripheral nerve and large-scale muscle injuries result in significant disability, necessitating the development of biomaterials that can restore functional deficits by promoting tissue regrowth in an electroactive environment. Among these materials, graphene is favored for its high conductivity, but its low bioactivity requires enhancement through biomimetic components. In this study, we extrusion printed graphene-poly(lactide-co-glycolide) (graphene) lattice scaffolds, aiming to increase bioactivity by incorporating decellularized extracellular matrix (dECM) derived from mouse pup skeletal muscle. We first evaluated these scaffolds using human-induced pluripotent stem cell (hiPSC)-derived motor neurons co-cultured with supportive glia, observing significant improvements in axon outgrowth. Next, we tested the scaffolds with C2C12 mouse and human primary myoblasts, finding no significant differences in myotube formation between dECM-graphene and graphene scaffolds. Finally, using a more complex hiPSC-derived 3D motor neuron spheroid model co-cultured with human myoblasts, we demonstrated that dECM-graphene scaffolds significantly improved axonal expansion towards peripheral myoblasts and increased axonal network density compared to graphene-only scaffolds. Features of early neuromuscular junction formation were identified near neuromuscular interfaces in both scaffold types. These findings suggest that dECM-graphene scaffolds are promising candidates for enhancing neuromuscular regeneration, offering robust support for the growth and development of diverse neuromuscular tissues.

Comparative Evaluation of Surgical Techniques for Pterygium Management: An In Vitro Study

ABSTRACT Background: Pterygium is a common ocular surface disorder characterized by the growth of fibrovascular tissue onto the cornea, leading to discomfort and visual impairment. Various surgical techniques, including conjunctival autografting, amniotic membrane transplantation, and bare sclera excision, are employed in the management of pterygium. Materials and Methods: Cultured human conjunctival epithelial cells were subjected to simulated pterygium conditions, mimicking the fibrovascular proliferation observed in vivo. Subsequently, different surgical techniques, including conjunctival autografting, amniotic membrane transplantation, and bare sclera excision, were simulated in vitro. Cell viability, proliferation, migration, and inflammatory cytokine expression were assessed using various assays, including MTT assay, scratch assay, and enzyme-linked immunosorbent assay (ELISA). Untreated cells served as controls for comparison. Results: Conjunctival autografting demonstrated superior outcomes in terms of cell viability and proliferation compared to amniotic membrane transplantation and bare sclera excision. Autografted cells exhibited a significantly higher percentage of viable cells and enhanced proliferative capacity compared to cells subjected to other surgical techniques (P < 0.05). Additionally, conjunctival autografting promoted faster cell migration into the defect area, resulting in more rapid wound closure compared to other techniques. Furthermore, reduced expression of inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), was observed in cells treated with conjunctival autografts compared to other groups. Conclusion: In vitro findings suggest that conjunctival autografting may offer superior outcomes in the management of pterygium compared to amniotic membrane transplantation and bare sclera excision.

Small AAAs: Recommendations for Rodent Model Research for the Identification of Novel Therapeutics.

Most abdominal aortic aneurysms (AAAs) are small with low rupture risk (<1%/y) when diagnosed but slowly expand to ≥55 mm and undergo surgical repair. Patients and clinicians require medications to limit AAA growth and rupture, but drugs effective in animal models have not translated to patients. Use models that simulate human AAA tissue pathology, growth patterns, and rupture; focus on the clinically relevant outcomes of growth and rupture; design studies with the rigor required of human clinical trials; monitor AAA growth using reproducible ultrasound; and perform studies in both males and females. The aortic adventitial elastase oral β-aminopropionitrile model has many strengths including simulating human AAA pathology and modeling prolonged aneurysm growth. The Ang II (angiotensin II) model performed less well as it better simulates acute aortic syndrome than AAA. The elastase plus TGFβ (transforming growth factor-β) blocking antibody model displays a high rupture rate, making prolonged monitoring of AAA growth not feasible. The elastase perfusion and calcium chloride models both display limited AAA growth.