In liver ischemia-reperfusion injury (LIRI), macrophage clearance of apoptotic cells via efferocytosis is crucial to prevent excessive inflammation and tissue damage. Here, we investigate the role of nucleotide-binding oligomerization domain-like receptor protein 3/cysteine-aspartate protease-1 (NLRP3/Caspase-1) signaling in modulating macrophage efferocytosis during LIRI. We observed robust activation of the NLRP3/Caspase-1 pathway during the early phase of LIRI. Genetic ablation of Nlrp3 or Caspase-1 substantially reduced LIRI severity. Notably, myeloid-specific Nlrp3 knockout mice exhibited less severe LIRI compared to hepatocyte-specific Nlrp3 knockouts, whereas macrophage-specific overexpression of Caspase-1 exacerbated tissue injury. Mechanistically, NLRP3/Caspase-1 activation enhances a disintegrin and metalloprotease protein-17 (ADAM17)-mediated cleavage of Mer proto-oncogene tyrosine kinase (MerTK), leading to impaired efferocytosis. Pharmacological inhibition of ADAM17 restored macrophage efferocytic capacity and alleviated LIRI. Clinically, elevated serum levels of soluble MerTK (s-Mer) correlated with hepatic injury severity and Caspase-1 activation in patients after partial hepatectomy or liver transplantation. Our findings suggest a potential therapeutic strategy for LIRI prevention and treatment.

Dry eye disease (DED) is correlated with corneal epithelial energy deficiency and mitochondrial injury, which may intensify ocular surface inflammation. Although Coenzyme Q10 (CoQ10) is an antioxidant related to mitochondria, its application is restricted by its poor aqueous solubility and instability. In this study, we developed a curdlan-mangiferin composite hydrogel (Q10@CM) to promote the ocular delivery of CoQ10 and explored its mechanisms in DED. Q10@CM was prepared through the thermogelation of curdlan (1%) with mangiferin (1.5%) within a pH range of 6.3-6.7 for the encapsulation of CoQ10. Q10@CM exhibited a porous filamentous microstructure, retained CoQ10 via non-covalent encapsulation, and converted CoQ10 from a crystalline to an amorphous dispersion. DED corneas showed abnormal energy metabolism accompanied by ultrastructural mitochondrial damage. Hyperosmolarity reproduced these phenotypes in human corneal epithelial cells (HCECs), resulting in an elevation of reactive oxygen species (ROS)/mitochondrial reactive oxygen species (mtROS), dysregulation of mitochondrial membrane potential (Delta Psi m) and opening of the mitochondrial permeability transition pore (mPTP), as well as the activation of inflammation. CoQ10 alleviated mitochondrial dysfunction and partially normalized metabolic parameters in vitro. In vivo, Q10@CM mitigated corneal epithelial injury, increased tear production, restored the equilibrium of energy metabolism, and inhibited corneal NLRP3 inflammasome signaling. Overall, Q10@CM enables solvent-free encapsulation and amorphous stabilization of hydrophobic CoQ10 for topical ocular administration, leading to metabolic rescue and antiinflammasome efficacy in DED.

ETHNOPHARMACOLOGICAL RELEVANCE:Shengxian Decoction (SXD) is a classical multi-herb prescription widely used in traditional Chinese medicine for chronic respiratory ailments. However, its pharmacological rationale and pro-resolving actions in idiopathic pulmonary fibrosis (IPF) have not been fully clarified. AIM OF THE STUDY:This study investigated the anti-fibrotic efficacy of SXD in a bleomycin (BLM)-induced mouse model and explored whether MerTK-dependent macrophage efferocytosis contributes to SXD-driven resolution. MATERIALS AND METHODS:Pulmonary fibrosis was induced by BLM in male C57BL/6 mice. Animals received SXD at two doses, with nintedanib (Nin) as a comparator; MerTK signaling was pharmacologically inhibited with UNC 2025. Disease severity was evaluated by survival and body-weight changes, histology (H&E, Masson's trichrome, Sirius Red), immunostaining (α-SMA, Ly6G, F4/80, CD68, MerTK), and molecular assays (RT-qPCR, ELISA, Western blot). SXD constituents were profiled by LC-MS. Candidate targets/pathways were explored via network pharmacology and lung transcriptomics (RNA-seq). Macrophage efferocytosis was quantified in lung sections (TUNEL/CD68) and in vitro using BALF-derived macrophages co-cultured with fluorescently labeled apoptotic neutrophils. RESULTS:SXD mitigated BLM-induced fibrosis, improving survival and limiting weight loss, while reducing Ashcroft scores, collagen accumulation, α-SMA production, and profibrotic factors (including Tgf-β, Pdgf-α, and Mmp12); the high-dose regimen produced the most pronounced benefit. SXD also blunted early inflammation by decreasing Ly6G+ neutrophil and F4/80+ macrophage recruitment and lowering TNF-α, IL-6, and IL-1β. LC-MS revealed a chemically complex formulation enriched in terpenoid components, and integrative network/RNA-seq analyses implicated multiple inflammation-fibrosis signaling programs. Mechanistically, SXD enhanced macrophage efferocytosis and increased MerTK and IL-10 expression; these pro-resolving and anti-fibrotic effects were predominantly abolished when MerTK was inhibited using UNC 2025. CONCLUSION:SXD conferred multi-target protection in BLM-induced pulmonary fibrosis and promoted resolution by enhancing macrophage apoptotic-cell clearance through a MerTK-dependent mechanism, which supported its translational potential for the intervention of IPF.

Diabetic cataract is characterized by early lens opacification. This study identifies a pathogenic axis that involves the N6-methyladenosine (m6A) demethylase fat mass and obesity-associated protein (FTO) and the mitochondria-enriched long non-coding RNA (lncRNA) RMRP. Transcriptomic analysis of lens epithelial cells (LECs) under high-glucose stress revealed that lncRNA RMRP was the most significantly downregulated lncRNA, while FTO was specifically upregulated. High glucose stimulated FTO to bind to RMRP, removed its m6A methylation, and expedited its degradation. Knockdown of RMRP led to mitochondrial DNA depletion, loss of respiratory chain subunits I, III, and V, bioenergetic failure, and structural damage. Notably, inhibition of FTO restored RMRP levels and rescued mitochondrial function under high-glucose conditions. In mice, overexpression of FTO in the anterior chamber induced lens opacification and mitochondrial defects, both of which were alleviated by co-expressing RMRP. In a mouse model of streptozotocin-induced diabetes, intracameral AAV-RMRP delivery restored RMRP expression specifically in LECs, suppressed cataract formation, alleviated cellular energy deficits, and restored mitochondrial DNA copy numbers and key mitochondrial biogenesis regulators. This work uncovers a new mechanism in diabetic cataracts: chronic hyperglycemia upregulates FTO, which degrades RMRP-causing mitochondrial dysfunction and lens opacity. Critically, rescuing RMRP function in a physiologically relevant diabetic model validates it as a promising therapeutic target for diabetic cataracts.

ETHNOPHARMACOLOGICAL RELEVANCE:Acute lung injury (ALI), a life-threatening inflammatory respiratory condition often progressing to respiratory distress syndrome (ARDS), has high mortality due to dysregulated immunity and lack of targeted therapies. Renshen Baidu Powder (RSBD) is a Traditional Chinese formula from the Song Dynasty's Taiping Huimin Heji Jufang, historically used for wind-cold-dampness-induced respiratory disorders in patients with Qi deficiency. Although several RSBD herbs show anti-inflammatory and immune-modulating effects, its specific mechanisms and therapeutic impact on ALI remain unclear. AIM OF THIS STUDY:To investigate the therapeutic effects of RSBD on mice with lipopolysaccharide (LPS)-induced ALI and to elucidate its underlying mechanism. STUDY DESIGN AND METHODS:A model of LPS-induced ALI was developed, wherein the mice received treatment with RSBD or the positive control drug, dexamethasone. The extent of lung injury and inflammation was evaluated by determining the pulmonary wet-to-dry weight ratio, conducting histopathological staining, and measuring the levels of inflammatory cytokines. The proportions of T helper 17 (Th17) and regulatory T (Treg) cells in the spleen were quantified through flow cytometry. The activity of the retinoic acid-related orphan receptor gamma t (RORγt)/interleukin-17 (IL-17) pathway was assessed using quantitative real-time PCR, western blotting, enzyme-linked immunosorbent assay and immunofluorescence. Mechanistic validation was conducted using the RORγt inverse agonist 13 (RORγt13), an IL-17 neutralizing antibody (IL-17NAb) and Hexyl 4-hydroxybenzoate (HexP). Additionally, the chemical constituents, potential targets, and signaling pathways of RSBD were explored by integrating liquid chromatography-mass spectrometry (LC-MS), network pharmacology, and mRNA sequencing. RESULTS:RSBD significantly alleviated LPS-induced lung injury by reducing pulmonary edema, inflammatory cell infiltration, and pro-inflammatory cytokine release. It restored immune balance by decreasing Th17 cells and increasing Treg cells, resulting in a higher Treg/Th17 ratio. RSBD suppressed RORγt and IL-17 expression while promoting IL-10 production. Network pharmacology and transcriptomics identified the IL-17 signaling pathway as a key target of RSBD, while LC-MS revealed abundant bioactive compounds-such as flavonoids and phenolics-that might contribute to its effects. Notably, RORγt13 and IL-17NAb replicated RSBD's protective effect by suppressing the differentiation into Th17 cells and preventing lung damage. In contrast, HexP, an RORγt agonist, nullified the protective effects of RSBD, which further validated the crucial role of the RORγt/IL-17 pathway in mediating its therapeutic action. CONCLUSION:RSBD alleviated LPS-induced ALI by inhibiting the RORγt/IL-17 pathway, restoring Treg/Th17 balance, and reducing pulmonary inflammation and damage. These results provided mechanistic support for RSBD as a multi-component immunomodulatory agent for ALI treatment.

The NOD-like receptor protein 3 (NLRP3) inflammasome plays a crucial role in human acute and chronic liver diseases. However, the role and cell-specific contribution of NLRP3 in liver regeneration remains unclear. Here, we found that NLRP3 was highly activated during the early stage of liver regeneration via 70% partial hepatectomy (PHx) mice model and clinical data. Global NLRP3 depletion or pharmacologically blocking NLRP3 significantly enhanced liver regeneration, while NLRP3 overexpression impaired it after PHx. Furthermore, mice with myeloid-specific knockout of Nlrp3 (Nlrp3Δmye), rather than hepatocyte-specific knockout (Nlrp3Δhep), showed improved liver regeneration compared to control (Nlrp3fl/fl). Mechanistically, deficiency of Nlrp3 promoted myeloid-epithelial-reproductive tyrosine kinase (MerTK)-mediated efferocytosis, thereby inducing macrophages toward a pro-reparative Ly6Clo phenotype. Notably, NLRP3 inhibition by MCC950 effectively reversed the impairment of liver regeneration after PHx in mice fed a high-fat diet. Our findings provide a potential therapeutic strategy for the prevention and treatment of post-hepatectomy liver failure.

After 70% partial hepatectomy (PHx), the metabolic pathways leading to hepatocyte lipid droplet accumulation during liver regeneration remain unclear. Aquaporin 5 (Aqp5) is an aquaporin that facilitates the transport of both water and hydrogen peroxide (H2O2). In this study, we observed delayed liver regeneration following PHx in Aqp5 knockout (Aqp5-/-) mice. Considering the role of Aqp5 in H2O2 transport, we hypothesized that deficiency in Aqp5 may induce oxidative stress and hepatocyte injury. Through the measurement of reactive oxygen species (ROS) and redox-related indices, we observed significant alterations in ROS levels as well as malondialdehyde (MDA), superoxide dismutase (SOD), and reduced glutathione (GSH) concentrations in regenerating livers lacking Aqp5 compared to wild-type controls. Oil Red O and 4-hydroxynonenal (4-HNE) staining results indicated that Aqp5 deficiency caused lipid accumulation during liver regeneration. The transcriptome sequencing results showed that the PPAR pathway is inhibited during the liver regeneration process in Aqp5 gene-knockout mice. The administration of the WY-14643 agonist, which targets the PPAR pathway, significantly mitigated delayed liver regeneration by enhancing hepatocyte proliferation and reducing lipid accumulation caused by Aqp5 deficiency. Our findings highlight the crucial role of Aqp5 in regulating H2O2 levels and lipid metabolism through the PPAR pathway during liver regeneration.

Purpose:Neurotrophic keratopathy (NK) is characterized by corneal nerve abnormalities. We investigated the role of aquaporin 5 (AQP5) in corneal nerve distribution and its regulation via the JUN-D-Ntn1/Slit3 signaling pathway. Methods:Wild-type (Aqp5+/+) and Aqp5 knockout (Aqp5-/-) mice were used. Corneas were dissected, permeabilized, and immunolabeled with neuron-specific βIII-tubulin to visualize corneal nerves. Primary trigeminal ganglion neurons were isolated and cocultured with recombinant NETRIN-1 or SLIT3. Chromatin immunoprecipitation PCR assessed JUN-D binding to Ntn1 and Slit3 promoters. Corneal epithelial scraping was performed, followed by subconjunctival injection of the JUN-D activator or inhibitor to evaluate effects on nerve regeneration. Results:Whole-mount immunostaining revealed reduced corneal nerve density in Aqp5-/- mice. Corneal epithelial NETRIN-1 levels were decreased, whereas SLIT3 levels were increased in Aqp5-/- mice. NETRIN-1 promoted, and SLIT3 inhibited, neuronal axon growth. JUN-D inhibition upregulated Ntn1 and downregulated Slit3. Modulation of JUN-D influenced corneal epithelial healing and nerve regeneration following corneal epithelial scraping. Conclusions:AQP5 deficiency disrupts corneal nerve architecture and may contribute to NK. AQP5 regulates corneal nerve distribution via the JUN-D-Ntn1/Slit3 pathway. These findings identify potential molecular targets for the prevention and treatment of NK.

OBJECTIVE:Acetaminophen (APAP) overdose causes severe hepatotoxicity, yet how mitochondrial injury in hepatocytes amplifies innate immune activation remains unclear. This study investigated whether extracellular vesicles released from APAP-injured hepatocytes (APAP-EVs) deliver damaged mitochondrial components to neutrophils, promoting NETs formation and worsening liver injury. METHODS:APAP-induced liver injury was established in C57BL/6 mice. Hepatocyte-derived EVs were isolated and intravenously administered. Liver injury was assessed by ALT, AST, necrosis, apoptosis, and NETs markers. GW4869, GSK484, RU.521, H-151 and ODN 2088 were used to block EVs release, NETs formation, cGAS-STING or TLR9 signaling. RESULTS:APAP-EVs treatment markedly exacerbated hepatotoxicity, increasing serum ALT (8775 ± 563.7 U/L vs. 6037 ± 436.5 U/L), AST (8952 ± 670.4 U/L vs. 5539 ± 525.8 U/L), and hepatic necrosis (56.10 ± 1.60 % U/L vs. 30.10 ± 1.52 % U/L) compared with APAP group. Blocking EVs release with GW4869 or inhibiting NETs formation with GSK484 significantly attenuated liver injury. Mechanistically, APAP-EVs activated cGAS-STING signaling in neutrophils to induce NETs formation, an effect abolished by the cGAS inhibitor RU.521 and the STING inhibitor H-151, whereas TLR9 inhibition (ODN 2088) had no effect. CONCLUSION:APAP-injured hepatocytes release EVs enriched with damaged mitochondrial cargo that activate cGAS-STING-dependent NETs formation, thereby amplifying liver injury. Targeting EVs biogenesis or NETs formation may provide effective therapeutic strategies for APAP-induced hepatotoxicity.

During the proliferative phase of liver regeneration, insufficient regulation of hepatocyte hydrogen peroxide (H2O2) overproduction can result in oxidative stress and hepatocyte death. This study aims to investigate the influence of Aquaporin 5 (Aqp5) on liver regeneration by evaluating its role in reactive oxygen species (ROS) generation and NLRP3-GSDMD-mediated pyroptosis. A 70 % partial hepatectomy (PHx) model was established in Aqp5-/- mice to evaluate the pathological changes in the liver. Reactive oxygen species (ROS) production was assessed using a dichlorodihydrofluorescein diacetate (DCFH-DA) assay. Aqp5 deficiency significantly increased ROS production, the number of TUNEL-positive cells, and disrupted mitochondrial membrane potential in the liver of Aqp5-deficient mice. The impact of Aqp5 on ROS/NLRP3/Gasdermin-D (GSDMD)-mediated pyroptosis was examined through the administration of N-acetyl-L-cysteine (NAC, an ROS scavenger) or disulfiram (DSF, a GSDMD inhibitor). In Aqp5-deficient mice, the regenerative liver exhibited increased expression of NLRP3, enhanced activation of caspase-1 and GSDMD, as well as elevated secretion of IL-1β. Treatment with DSF significantly attenuated GSDMD-mediated pyroptosis triggered by Aqp5 deficiency in the regenerating liver. Furthermore, the administration of NAC to Aqp5-deficient mice resulted in a reduction in the expression levels of NLRP3, the activity levels of caspase-1 and GSDMD, as well as the release of IL-1β. Our findings indicate that the deficiency of Aqp5 facilitates GSDMD activation through the production of ROS. The suppression of ROS or inhibition of GSDMD significantly alleviates the damage and pyroptosis observed in Aqp5-deficient regenerative liver.

Mitochondria play a crucial role in energy production and are intimately associated with ocular function. Mitochondrial dysfunction can trigger oxidative stress and inflammation, adversely affecting key ocular structures such as the lacrimal gland, lens, retina, and trabecular meshwork. This dysfunction may compromise the barrier properties of the trabecular meshwork, impeding aqueous humour outflow, elevating intraocular pressure, and resulting in optic nerve damage and primary open-angle glaucoma. Additionally, impaired mitochondrial homeostasis can contribute to dry eye, cataracts, and age-related macular degeneration (AMD) by disrupting the function of the lacrimal gland, lens, and macula. Imbalanced mitochondrial homeostasis primarily involves four pathological features: disruption of mitochondrial quality control, mitochondrial damage (inducing inflammation), excessive production of mitochondrial reactive oxygen species (ROS) (initiating oxidative stress), and disturbances in mitochondrial calcium (Ca2+) homeostasis. Oxidative stress and inflammation are central mechanisms of cellular injury. Pharmacological strategies aimed at reducing excessive ROS, restoring redox balance, and mitigating oxidative and inflammatory damage show therapeutic promise. Moreover, enhancing mitochondrial function through pharmacological agents, replacing damaged mitochondria, and promoting mitochondrial rejuvenation represent emerging treatment avenues. This review explores the relationship between mitochondrial dysfunction and ocular diseases such as dry eye, glaucoma, cataracts, and AMD, with a focus on associated mechanisms and potential therapeutic interventions.

Acetaminophen (APAP) overdose is the primary cause of drug-induced acute liver failure in numerous Western countries. NLR family pyrin domain containing 3 (NLRP3) inflammasome activation serves a pivotal role in the pathogenesis of various forms of acute liver injury. However, the cellular source for NLRP3 induction and its involvement during APAP-induced hepatotoxicity have not been thoroughly investigated. In the present study, hematoxylin and eosin staining was performed to assess histopathological changes of liver tissue. Immunohistochemistry staining(NLRP3, Caspase-1, IL-1 beta, GSDMD and Caspase-3), western blotting (NLRP3, Caspase-1, IL-1 beta, GSDMD and Caspase-3) and RT-qPCR (NLRP3, Caspase-1 and IL-1 beta) were performed to assess the expression of NLRP3/GSDMD signaling pathway. TUNEL staining was performed to assess apoptosis of liver tissue. The serum expression levels of inflammatory factors (IL-6, IL-18, IL-1 beta and TNF-alpha) were assessed using ELISA and inflammation of liver tissue was assessed using immunohistochemistry (Ly6G and CD68) and RT-qPCR (TNF-alpha, Il-6, Mcp-1, Cxcl-1, Cxcl-2). A Cell Counting Kit-8 was performed to assess cell viability and apoptosis. Protein and gene expression were analyzed by western blotting (PCNA, CCND1) and RT-qPCR (CyclinA2, CyclinD1 and CyclinE1). Through investigation of an APAP-induced acute liver injury model (AILI), the present study demonstrated that APAP overdose induced activation of NLRP3 and cleavage of gasdermin D (GSDMD) in hepatocytes, both in vivo and in vitro. Additionally, mice with hepatocyte-specific knockout of Nlrp3 exhibited reduced liver injury and lower mortality following APAP intervention, accompanied by decreased infiltration of inflammatory cells and attenuated inflammatory response. Furthermore, pharmacological blockade of NLRP3/GSDMD signaling using MCC950 or disulfiram significantly ameliorated liver injury and reduced hepatocyte death. Notably, hepatocyte Nlrp3 deficiency promoted liver recovery by enhancing hepatocyte proliferation. Collectively, the present study demonstrated that inhibition of the NLRP3 inflammasome protects against APAP-induced acute liver injury by reducing hepatocyte pyroptosis and suggests that targeting NLRP3 may hold therapeutic potential for treating AILI.

Purpose:Abnormalities in aquaporins are implicated in the pathological progression of dry eye syndrome. Retinoic acid (RA) regulates cellular proliferation, differentiation, and apoptosis in the cornea, thereby being associated with dry eye disease (DED). The objective of this study is to explore the underlying mechanisms responsible for RA metabolic abnormalities in corneas lacking aquaporin 5 (AQP5). Methods:Dry eye (DE) models were induced via subcutaneous scopolamine hydrobromide. Aqp5 knockout (Aqp5-/-) mice and DE mice were utilized to assess corneal epithelial alterations. Tear secretion, goblet cell counts, and corneal punctate defects were evaluated. The impact of Aqp5 on RA-related enzymes and receptors was investigated using pharmacological RA or SR (A JunB inhibitor), a transcription factor JunB inhibitor, treatment in mouse corneal epithelial cells (CECs), or human corneal epithelial cells (HCECs). The HCECs and NaCl-treated HCECs underwent quantitative real-time PCR (qRT-PCR), immunofluorescent, Western blot, and TUNEL assays. The regulation of transcription factor JunB on Aldh1a1 was explored via ChIP-PCR. Results:Aqp5 and Aldh1a1 were reduced in both CECs of DE mice and NaCl-induced HCECs. Aqp5-/- mice exhibited DE phenotype and reduced Aldh1a1. RA treatment reduced apoptosis, promoted proliferation, and improved the DE phenotype in Aqp5-/- mice. JunB enrichment in the Aldh1a1 promoter was identified by ChIP-PCR. SR significantly increased Aldh1a1 expression, Ki67, and ΔNp63-positive cells, and decreased TUNEL-positive cells in CECs and HCECs. Conclusions:Our findings demonstrated the downregulation of Aqp5 expression and aberrant RA metabolism in DE conditions. Knockout of Aqp5 resulted in reduced production of RA through activation of JunB, subsequently leading to the manifestation of DE symptoms.

Vitamin A is an essential fat-soluble vitamin that cannot be endogenously synthesized by the human body. Retinoic acid (RA) is the biologically active form of vitamin A. Utilizing both nuclear and non-nuclear receptor-mediated pathways, RA plays a crucial role in regulating various biological processes, including apoptosis, differentiation, and anti-inflammatory properties within the cornea and conjunctiva. In addition, RA has been demonstrated to exert a significant influence on anti-tumor mechanisms. Disruption of RA signaling can result in corneal defects, anophthalmia, and microphthalmia. However, the beneficial effects of RA are only observed when it is administered at appropriate dosages, and higher doses have an adverse impact. Ocular abnormalities are often early indicators of a vitamin A deficiency. The lacrimal gland secretes vitamin A onto the ocular surface, where it is metabolized into RA via two sequential steps. This article provides a comprehensive overview of how vitamin A is transformed and transported from the intestine to the ocular surface, ultimately contributing to the maintenance of the normal physiological function of the ocular surface.

Hepatic ischemia-reperfusion injury (HIRI) is a significant issue during liver transplantation and surgery, contributing to the liver failure or even mortality. Although extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) have shown substantial potentials in cell replacement therapy of various organ ischemia reperfusion injuries (IRIs), the precise mechanisms remain unclear. In this study, we demonstrate that systemic MSC-EVs administration is predominantly absorbed by macrophages, and verified that it could significantly reduce the liver injury and inflammatory response in mice suffering from HIRI. Furthermore, treatment with MSC-EVs induces macrophage polarization toward an anti-inflammatory phenotype. Mechanistically, proteomic profiling reveals an enrichment of growth arrest-specific 6 (GAS6) in MSC-EVs, significantly promoting the activation of myeloid-epithelial-reproductive tyrosine kinase/extracellular regulated protein kinases/cyclooxygenase 2 (MerTK/ERK/COX2) signaling pathway in macrophages and further enhancing their efferocytosis efficiency. Knockdown of GAS6 via lentiviral transfection or inhibition of MerTK using UNC2025 (a MerTK small molecule inhibitor) partially eliminates the protective effects of MSC-EVs on macrophage efferocytosis and liver injury. Overall, our findings support that MSC-EVs enriched GAS6 execute an anti-inflammation effect, highlighting that treatment based on the modulation of macrophage function by MSC-EVs as a promising approach in IRI.HIRI is a thorny problem after liver surgery such as liver transplantation. In a murine model of HIRI, MSC-EVs enriched GAS6 effectively enhance macrophage efferocytosis both in vivo and in vitro through the GAS6/MerTK/ERK/COX2 signaling pathway and significantly mitigate liver injury. This image was drawn by the authors.

Ferroptosis is a newly discovered type of regulated cell death participated in multiple diseases. Different from other classical cell death programs such as necrosis and apoptosis, ferroptosis involving iron-catalyzed lipid peroxidation is characterized by Fe2+ accumulation and mitochondria alterations. The phenomenon of oxidative stress following organ ischemia-reperfusion (I/R) has recently garnered attention for its connection to the onset of ferroptosis and subsequent reperfusion injuries. This article provides a comprehensive overview underlying the mechanisms of ferroptosis, with a further focus on the latest research progress regarding interference with ferroptotic pathways in organ I/R injuries, such as intestine, lung, heart, kidney, liver, and brain. Understanding the links between ferroptosis and I/R injury may inform potential therapeutic strategies and targeted agents.

Purpose:Dry eye disease (DED) is multifactorial and associated with nerve abnormalities. We explored an Aquaporin 5 (AQP5)-deficiency-induced JunB activation mechanism, which causes abnormal lacrimal gland (LG) nerve distribution through Slit2 upregulation and Netrin-1 repression. Methods:Aqp5 knockout (Aqp5-/-) and wild-type (Aqp5+/+) mice were studied. LGs were permeabilized and stained with neuronal class III β-tubulin, tyrosine hydroxylase (TH), vasoactive intestinal peptide (VIP), and calcitonin gene-related peptide (CGRP). Whole-mount images were acquired through tissue clearing and 3D fluorescence imaging. Mouse primary trigeminal ganglion (TG) neurons were treated with LG extracts and Netrin-1/Slit2 neutralizing antibody. Transcription factor (TF) prediction and chromatin immunoprecipitation-polymerase chain reaction (ChIP-PCR) experiments verified the JunB binding and regulatory effect on Netrin-1 and Slit2. Results:Three-dimensional tissue and section immunofluorescence showed reduced LG nerves in Aqp5-/- mice, with sympathetic and sensory nerves significantly decreased. Netrin-1 was reduced and Slit2 increased in Aqp5-/- mice LGs. Aqp5+/+ mice LG tissue extracts (TEs) promoted Aqp5-/- TG neurons axon growth, but Netrin-1 neutralizing antibody (NAb) could inhibit that promotion. Aqp5-/- mice LG TEs inhibited Aqp5+/+ TG axon growth, but Slit2 NAb alleviated that inhibition. Furthermore, JunB, a Netrin-1 and Slit2 TF, could bind them and regulate their expression. SR11302, meanwhile, reversed the Netrin-1 and Slit2 shifts caused by AQP5 deficiency. Conclusions:AQP5 deficiency causes LG nerve abnormalities. Persistent JunB activation, the common denominator for Netrin-1 suppression and Slit2 induction, was found in Aqp5-/- mice LG epithelial cells. This affected sensory and sympathetic nerve fibers' distribution in LGs. Our findings provide insights into preventing, reversing, and treating DED.

Background Coronavirus disease 2019 (COVID-19) is an infectious respiratory disease prevalent worldwide with a high mortality rate, and there is currently no specific medicine to treat patients. Objective We aimed to assess the safety and efficacy of stem cell therapy for COVID-19 by providing references for subsequent clinical treatments and trials. Methods We systematically searched PubMed, Embase, Cochrane, and Web of Science, using the following keywords: "stem cell" or "stromal cell" and "COVID-19." Controlled clinical trials published in English until 24(th) August 2021 were included. We followed the PRISMA guidelines and used Cochrane Collaboration's tool for assessing the risk of bias. We analysed the data using a fixed-effect model. Results We identified 1779 studies, out of which eight were eligible and included in this study. Eight relevant studies consisted of 156 patients treated with stem cells and 144 controls (300 individuals in total). There were no SAEs associated with stem cell therapy in all six studies, and no significant differences in AEs (p = 0.09, I-2 = 40%, OR = 0.53, 95% CI: 0.26 to 1.09) between the experimental group and control group were observed. Moreover, the meta-analysis found that stem cell therapy effectively reduced the high mortality rate of COVID-19 (14/156 vs. 43/144; p<0.0001, I-2 = 0%, OR=0.18, 95% CI: 0.08 to 0.41). Conclusion This study suggests that MSCs therapy for COVID-19 has shown some promising results in safety and efficacy. It effectively reduces the high mortality rate of COVID-19 and does not increase the incidence of adverse events.