Upadacitinib inhibits corneal inflammation and neovascularization by suppressing M1 macrophage infiltration in the corneal alkali burn model

Neutrophil extracellular traps-mediated upregulation of HIF-1α promotes corneal neovascularization

OBJECTIVES

The objective of this study is to examine the impact of neutrophil extracellular traps (NETs) on angiogenesis, both in vitro and in vivo contexts, as well as to elucidate the regulatory function of hypoxia-inducible factor (HIF-1α).

METHODS

The study focused on investigating the regulatory function of HIF-1α in the induction of NETs formation. In vivo, following NaOH stimulation, the formation of NETs was quantitatively assessed through immunofluorescence staining employing specific markers, namely SYTOX Green and PicoGreen. Furthermore, mice were administered with HIF-1α, and seven days post-alkali burn, the formation of NETs in the cornea was evaluated by immunofluorescence staining techniques. Protein immunoblotting analysis validated an increase inHIF-1α expression within human umbilical vein endothelial cells (HUVECs) that were induced to form by NETs. In vitro, human neutrophils were subjected to HIF-1α treatment. Subsequent to NaOH stimulation, the NETs mesh was isolated and co-cultured with HUVECs. The migratory capacity and angiogenic potential of HUVECs were then quantitatively evaluated.

RESULTS

Upon exposure to NaOH, a notable increase in SYTOX fluorescence was observed in neutrophils, indicative of the formation of a prominent network structure. Furthermore, a marked elevation in HIF-1α protein expression was detected in mouse corneal tissue that had undergone NETs formation, hinting at a potential role of NETs in mediating the up-regulation of HIF-1α. The outcomes of hematoxylin and eosin (H&E) staining, coupled with immunofluorescence staining, revealed an augmentation in neutrophils counts, with NETs exhibiting a marked potentiation of corneal neovascularization. In vitro assessments further demonstrated that HIF-1α played a stimulatory role in promoting the migration and tubular morphogenesis of HUVECs.

CONCLUSION

Exposure to sodium hydroxide serves as a trigger for the induction of NETs formation. NETs mediated an up-regulation of HIF-1α, which subsequently promotes angiogenesis and inflammatory activation in HUVECs. Consequently, this process leads to an enhancement of corneal neovascularization and inflammatory response.

Mineralocorticoid receptor antagonism improves corneal integrity in a rat model of limbal stem cell deficiency

Limbal stem cell deficiency (LSCD) is a sight-threatening condition caused by the loss and/or dysfunction of limbal stem cells (LSCs), which are essential for corneal epithelial regeneration and homeostasis and are critical for maintaining corneal transparency. We have previously shown that specific inactivation of the endothelial mineralocorticoid receptor (MR) inhibits corneal neovascularization (CN) and that MR antagonists (MRA) improve corneal epithelial wound healing. This study investigated the therapeutic potential of MRA in LSCD and their mechanisms of action. Using a rat model of LSCD, systemic administration of spironolactone (SPL) or a more specific MRA, eplerenone, similarly reduced CN and corneal oedema, demonstrating MR-specific effects. SPL further limited inflammation, enhanced the corneal epithelial barrier, reduced corneal conjunctivalization and promoted nerve regeneration, highlighting its potential to improve corneal integrity. Transcriptomic analysis revealed that SPL upregulated genes associated with LSC maintenance (Tp63, Wnt6), corneal epithelial differentiation (Vdr, Fermt1, Ehf) and nerve regeneration (Sprr1a, Anxa1), while downregulating genes associated with angiogenesis (Kdr, Scube2), inflammation (Ccl2, Cxcl1) and fibrosis (Fbln1, Snai1). Conversely, transgenic rats overexpressing human NR3C2 encoding MR showed corneal epithelial irregularities and dysregulation of genes related to extracellular matrix remodeling and fibrosis (Matn3, Serpine2, Fmod, Bgn, Ddr2), angiogenesis (Nrp2, Scube1) and limbal cell function (Ifitm3). These findings demonstrate that activation of the MR pathway disrupts limbal and corneal homeostasis and that SPL effectively modulates critical mechanisms in LSCD, offering promising therapeutic potential to reduce CN and improve corneal epithelial barrier integrity.

Cyclopamine inhibits corneal neovascularization and fibrosis by alleviating inflammatory macrophage recruitment and endothelial cell activation

PURPOSE

To explore the function of cyclopamine in corneal neovascularization and subsequent fibrosis after cornea alkali-burn injury.

METHODS

In vivo, mice cornea were injured by NaOH, and then treated with cyclopamine, clodronate liposomes (CLO-LPS), and vehicle of cyclopamine separately by subconjunctival injections. Clinical features were observed and pathological characteristics were examined. In vitro, M1 macrophages (M1φ) and human umbilical vein endothelial cells (HUVECs) were co-cultured, and the abilities of proliferation, migration, and tube formation of HUVECs were detected under different interventions of M1φ.

RESULTS

Alkali-burn injury induced massive angiogenesis and decreased transparency of the cornea, along with numerous macrophages infiltration and Shh protein expression in the cornea. However, corneal neovascularization, macrophage infiltration, and Shh expression could suppressed by cyclopamine and CLO-LPS significantly. In addition, treatment with cyclopamine also reduced the expression of inflammatory factors (TNF-α, IL-6) and fibrosis factors (VIM, α-SMA). In vitro, M1φ promotes migration and tube formation of HUVECs by secreting Shh protein, which could be inhibited by cyclopamine.

CONCLUSION

Cyclopamine could suppress inflammation and angiogenesis of alkali-burned cornea, as well as subsequent fibrosis. The study reveals that cyclopamine suppresses corneal neovascularization in a dual mechanism of inhibiting macrophage infiltration and suppressing Shh signaling.

Photodynamic hemostatic silk fibroin film with photo-controllable modulation of macrophages for bacteria-infected wound healing

Massive hemorrhage and chronic wounds caused by bacterial infections after trauma are significant challenges in clinical practice. An ideal hemostatic wound dressing should simultaneously manage bleeding and prevent bacterial infections and also hold excellent biocompatibility and bioactivities to successfully modulate immune microenvironments to promote wound healing. In this study, a silk fibroin-based light-responsive film was demonstrated to possess effective capacity of light-induced non-compressible hemostasis on liver hemorrhage and tail bleeding in vivo by binding with blood platelets to promote the clotting cascade. The blood loss of the rats was significantly less after C-MASiF films were applied, which were 1223.33 ± 347.9 mg (liver trauma) and 363.33 ± 60.28 mg (tail trimming). Importantly, the films exhibited photo-controllable modulation activity on macrophages through repeated near-infrared irradiation to regulate the immune microenvironment to enhance photodynamic antibacterial therapy. Moreover, the light-responsive silk fibroin film effectively promoted Staphylococcus aureus infected burn wound healing in vivo. The quantity of residual bacteria in the wound sites of mice in the C-MASiF films group (0.05 ± 0.0047 × 108 CFU mL-1) was considerably less than that in the control group (3.18 ± 0.75 × 108 CFU mL-1), and the wound area in the C-MASiF group (78.03% ± 4.12%) was considerably smaller than that in the control group (60.33% ± 8.81%) after 14 days. Overall, this light-responsive silk fibroin film can provide a powerful strategy for wound healing of burns.

Innate immunity champions: The diverse functions of macrophages

Macrophages are instrumental in maintaining tissue homeostasis, modulating inflammation, and driving regeneration. The advent of omics techniques has led to the identification of numerous tissue-specific macrophage subtypes, thereby introducing the concept of the "macrophage niche". This paradigm underscores the ability of macrophages to adapt their functions based on environmental cues, such as tissue-specific signals. This adaptability is closely linked to their metabolic states, which are crucial for their function and role in health and disease. Macrophage metabolism is central to their ability to switch between proinflammatory and anti-inflammatory states. In this regard, environmental factors, including the extracellular matrix, cellular interactions, and microbial metabolites, profoundly influence macrophage behavior. Moreover, diet and gut microbiota significantly impact macrophage function, with nutrients and microbial metabolites influencing their activity and contributing to conditions like inflammatory bowel disease. Targeting specific macrophage functions and their metabolic processes is leading to the development of novel treatments for a range of chronic inflammatory conditions. The exploration of macrophage biology enriches our understanding of immune regulation and holds the promise of innovative approaches to managing diseases marked by inflammation and immune dysfunction, offering a frontier for scientific and clinical advancement.

Prediction of immune molecules activity during burn wound healing among elderly patients: in-silico analyses: experimental research

Introduction

Burn injuries lead to dysregulation of immune molecules, impacting cellular and humoral immune pathways. This study aims to determine the prediction of immune molecule activity during burn wound healing among elderly patients.

Methods

The current study utilized the Gene Expression Omnibus (GEO) database to extract the proper gene set. Also, the literature review was conducted in the present study to find immune signatures. The study used the "enrich r" website to identify the biological functions of extracted genes. The critical gene modules related to mortality were identified using the weighted gene co-expression network analysis (WGCNA) R package.

Results

The appreciated GSE was extracted. According to the data, the most upregulated signatures were related to natural killer (NK) cells, and the most downregulated signatures were associated with M1 macrophages. Also, the results of WGCNA have shown that the most related gene modules (P<107 and score 0.17) to mortality were investigated, and the modules 100 first genes were extracted. Additionally, the enrich r analysis has demonstrated related pathways, including the immune process, including regulation of histamine secreted from mast cell (P<0.05), T helper 17 cell differentiation (P<0.05), and autophagy (P<0.05) were obtained. Finally, by network analysis, the critical gene "B3GNT5" were obtained (degree>ten and "betweenness and centrality">30 were considered).

Conclusion

The study identified significant changes in macrophage and NK cell expression patterns post-burn injury, linking them to potential improvements in clinical outcomes and wound healing. The gene B3GNT5, associated with mortality, was highlighted as a key marker for prognostic evaluation.

Cell spray printing combined with Lycium barbarum glycopeptide promotes repair of corneal epithelial injury

The corneal epithelium, located as the outermost layer of the cornea, is inherently susceptible to injuries that may lead to corneal opacities and compromise visual acuity. Rapid restoration of corneal epithelial injury is crucial for maintaining the transparency and integrity of the cornea. Cell spray treatment emerges as an innovative and effective approach in the field of regenerative medicine. In our study, a cell spray printing platform was established, and the optimal printing parameters were determined to be a printing air pressure of 5 PSI (34.47 kPa) and a liquid flow rate of 30 ml/h. Under these conditions, the viability and phenotype of spray-printed corneal epithelial cells were preserved. Moreover, Lycium barbarum glycopeptide (LBGP), a glycoprotein purified from wolfberry, enhanced proliferation while simultaneously inhibiting apoptosis of the spray-printed corneal epithelial cells. We found that the combination of cell spray printing and LBGP facilitated the rapid construction of multilayered cell sheets on flat and curved collagen membranes in vitro. Furthermore, the combined cell spray printing and LBGP accelerated the recovery of the rat corneal epithelium in the mechanical injury model. Our findings offer a therapeutic avenue for addressing corneal epithelial injuries and regeneration.

INOS ablation promotes corneal wound healing via activation of Akt signaling

Corneal injury leads to impaired normal structure of the cornea. Improving the wound healing process in epithelial cells significantly contributes to ocular damage treatments. Here, we aimed to investigate the potential mechanisms of nitric oxide (NO) and its mediator, inducible nitric oxide synthase (iNOS), in the process of corneal wound healing. We established a corneal injury model of iNOS-/- mice, and treated human corneal epithelial cell lines (HCE-2) with the iNOS inhibitor L-INL, with or without NO replenishment by supplying sodium nitroferricyanide dihydrate (SNP). Our findings showed that inhibition of NO/iNOS accelerated corneal repair, enhanced uPAR (a receptor protein indicating the migration ability), and improved epithelial cell migration. Furthermore, NO/iNOS ablation activated Akt phosphorylation, reduced neutrophil marker protein MPO expression, and downregulated the transcription of inflammation cytokines CXCL-1, CXCL-2, IL-1β, IL-6, and TNF-α. However, the protective effects of NO/iNOS inhibition are significantly reduced by NO replenishment when treated with SNP. Therefore, we confirmed that inhibiting NO/iNOS improved the corneal wound healing by facilitating epithelial cell migration and reducing inflammatory reactions, which might be related to the activation of the Akt signaling pathway.

Research progress of photo-crosslink hydrogels in ophthalmology: A comprehensive review focus on the applications

Hydrogel presents a three-dimensional polymer network with high water content. Over the past decade, hydrogel has developed from static material to intelligent material with controllable response. Various stimuli are involved in the formation of hydrogel network, among which photo-stimulation has attracted wide attention due to the advantages of controllable conditions, which has a good application prospect in the treatment of ophthalmic diseases. This paper reviews the application of photo-crosslink hydrogels in ophthalmology, focusing on the types of photo-crosslink hydrogels and their applications in ophthalmology, including drug delivery, tissue engineering and 3D printing. In addition, the limitations and future prospects of photo-crosslink hydrogels are also provided.

The role of the JAK/STAT3 signaling pathway in acquired corneal diseases

Acquired corneal diseases such as dry eye disease (DED), keratitis and corneal alkali burns are significant contributors to vision impairment worldwide, and more effective and innovative therapies are urgently needed. The Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) signaling pathway plays an indispensable role in cell metabolism, inflammation and the immune response. Studies have shown that regulators of this pathway are extensively expressed in the cornea, inducing significant activation of JAK/STAT3 signaling in specific acquired corneal diseases. The activation of JAK/STAT3 signaling contributes to various pathophysiological processes in the cornea, including inflammation, neovascularization, fibrosis, and wound healing. In the context of DED, the hypertonic environment activates JAK/STAT3 signaling to stimulate corneal inflammation. Inflammation and injury progression in infectious keratitis can also be modulated by JAK/STAT3 signaling. Furthermore, JAK/STAT3 signaling is involved in every stage of corneal repair after alkali burns, including acute inflammation, angiogenesis and fibrosis. Treatments modulating JAK/STAT3 signaling have shown promising results in attenuating corneal damage, indicating its potential as a novel therapeutic target. Thus, this review emphasizes the multiple roles of the JAK/STAT3 signaling pathway in common acquired corneal disorders and summarizes the current achievements of JAK/STAT3-targeting therapy to provide new insights into future applications.

Smart coating by thermo-sensitive Pluronic F-127 for enhanced corneal healing via delivery of biological macromolecule progranulin

As a leading cause of vision impairment and blindness, corneal alkali burns lead to long-term visual deterioration or even permanent visual impairment while effective treatment strategies remain a challenge. Herein, a thermo-sensitive hydrogel with the combination of multi-functional protein progranulin (PGRN), a biological macromolecule consisting of several hundred amino acids and possessing a high molecular weight, is efficiently prepared through a convenient stirring and mixing at the low temperature. The hydrogel can be easily administrated to the ocular surface contacting with the cornea, which can be immediately transformed into gel-like state due to the thermo-responsive behavior, realizing a site-specific coating to isolate further external stimulation. The smart coating not only exhibits excellent transparency and biocompatibility, but also presents a constant delivery of PGRN, creating a nutritious and supportive micro-environment for the ocular surface. The results show that the prepared functional hydrogel can efficiently suppress inflammation, accelerate re-epithelization, and intriguingly enhance axonal regeneration via modulation of multiple signaling pathways, indicating the novel designed HydrogelPGRN is a promising therapy option for serious corneal injury.

Preparation of a Sunitinib loaded microemulsion for ocular delivery and evaluation for the treatment of corneal neovascularization in vitro and in vivo

Background: Corneal neovascularization (CNV) is a pathological condition that can disrupt corneal transparency, thus harming visual acuity. However, there is no effective drug to treat CNV. Sunitinib (STB), a small-molecule multiple receptor tyrosine kinase inhibitor, was shown to have an effect on CNV. The purpose of this study was to develop an STB microemulsion (STB-ME) eye drop to inhibit CNV by topical application. Methods: We successfully prepared an STB-ME by the phase inversion emulsification method, and the physicochemical properties of STB-MEs were investigated. The short-term storage stability, cytotoxicity to human corneal epithelial cells, drug release, ocular irritation, ocular pharmacokinetics and the inhibitory effect on CNV were evaluated in vitro and in vivo. Results: The optimal formulation of STB-ME is composed of oleic acid, CRH 40, Transcutol P, water and sodium hyaluronate (SH). It is a uniform spherical particle with a mean droplet size of 18.74 ± 0.09 nm and a polydispersity index of 0.196 ± 0.004. In the in vitro drug release results, STB-ME showed sustained release and was best fitted by a Korsmeyer-Peppas model (R ² = 0.9960). The results of the ocular pharmacokinetics in rabbits showed that the formulation containing SH increased the bioavailability in the cornea (2.47-fold) and conjunctiva (2.14-fold). STB-ME (0.05% and 0.1%), administered topically, suppressed alkali burn-induced CNV in mice more effectively than saline, and high-dose (0.1%) STB-ME had similar efficacy to dexamethasone (0.025%). Conclusion: This study provides a promising formulation of STB-ME for the inhibition of CNV by topical administration, which has the excellent characteristics of effectiveness, sustained release and high ocular bioavailability.