Role of macrophage in ocular neovascularization.

Ocular neovascularization is the leading cause of blindness in clinical settings. Pathological angiogenesis of the eye can be divided into corneal neovascularization (CoNV), retinal neovascularization (RNV, including diabetic retinopathy and retinopathy of prematurity), and choroidal neovascularization (CNV) based on the anatomical location of abnormal neovascularization. Although anti-Vascular endothelial growth factor (VEGF) agents have wide-ranging clinical applications and are an effective treatment for neovascular eye disease, many deficiencies in this treatment strategy remain. Recently, emerging evidence has demonstrated that macrophages are vital during the process of physiological and pathological angiogenesis. Monocyte-macrophage lineage is diverse and plastic, they can shift between different activation modes and have different functions. Due to the obvious regulatory effect of macrophages on inflammation and angiogenesis, macrophages have been increasingly studied in the field of ophthalmology. Here, we detail how macrophage activated and the role of different subtypes of macrophages in the pathogenesis of ocular neovascularization. The complexity of macrophages has recently taken center stage owing to their subset diversity and tightly regulated molecular and metabolic phenotypes. In this review, we reveal the functional and phenotypic characterization of macrophage subsets associated with ocular neovascularization, more in-depth research is needed to explore the specific mechanisms by which macrophages regulate angiogenesis as well as macrophage polarization. Targeted regulation of macrophage differentiation based on their phenotype and function could be an effective approach to treat and manage ocular neovascularization in the future.

Tocilizumab attenuates choroidal neovascularization by regulating macrophage polarization through the IL-6R/STAT3/VEGF pathway.

Globally, age-related macular degeneration (AMD) is the leading cause of irreversible visual impairment. Up to 80% of severe vision loss is caused by AMD, which is characterized by the development of choroidal neovascularization (CNV). Uncertainty exists regarding the precise pathophysiological mechanisms of CNV. It has been suggested that the interleukin (IL) IL-6/IL-6R signaling pathway is crucial in the progression of CNV. Tocilizumab (TCZ), a monoclonal antibody, binds to soluble and membrane-bound IL-6R and competitively inhibits IL-6 downstream signaling. Previous research has demonstrated that TCZ promotes several roles related to inflammation and neovascularization. However, the effects of TCZ on CNV and the underlying mechanism are still unknown. This study found that TCZ administration decreased the area and leakage of CNV lesions in the mice model of laser-induced CNV. Additionally, results demonstrated that TCZ promotes the expression of iNOS, CCL-3, CCL-5, TNF-α and inhibits the expression of Arg-1, IL-10, YM-1 and CD206. Furthermore, TCZ treatment inhibited the signal transducer and activator of transcription (STAT) STAT3/vascular endothelial growth factor (VEGF) pathway, which was activated after CNV formation. Colivelin, a STAT3 agonist, reversed the inhibitory effects of TCZ on CNV formation and macrophage polarization. In a mouse model of laser-induced CNV, our findings demonstrated that TCZ attenuated CNV formation and inhibited the leakage of CNV lesions by regulating macrophage polarization via inhibiting the STAT3/VEGF axis. TCZ is the potential therapeutic strategy for CNV.

Reinforced dentin remineralization via a novel dual-affinity peptide.

OBJECTIVES: In light of the constantly flowing saliva, anti-caries remineralization agents are inclined to be taken away. Owing to their limited residence time, the remineralization effect is not as desirable as expected. Hence, our study aimed to synthesize a novel peptide (DGP) with high affinity to both collagen fibrils and hydroxyapatite, and investigated its dentin remineralization efficacy in vitro and anti-caries capability in vivo. METHODS: DGP was synthesized through Fmoc solid-phase reaction. The binding ability and interaction mechanism of DGP to demineralized dentin were investigated. Dentin specimens were demineralized, then treated with DGP and deionized water respectively. The specimens were incubated in artificial saliva and in-vitro remineralization effectiveness was analyzed after 14 days. The rat caries model was established to further scrutinize the in-vivo efficacy of caries prevention. RESULTS: DGP possesses an enhanced adhesion force of 12.29 ± 1.12 nN to demineralized dentin. The favorable adsorption capacity is ascribed to the stable hydrogen bonds between S2P-101 and ASP-100 of DGP and GLY33 and PRO-16 of collagen fibers. Abundant mineral deposits and remarkable tubule occlusion were observed in the DGP group. DGP-treated dentin obtained notable microhardness recovery and higher mineral content after a 14-day remineralization regimen. DGP also demonstrated potent caries prevention in vivo, with substantially fewer carious lesions and significantly lower Keyes scoring. SIGNIFICANCE: DGP proves to possess a high affinity to demineralized dentin regardless of saliva flowing, thus enhancing remineralization potency significantly in vitro and in vivo, potential for dental caries prevention and combatting initial dentin caries clinically.

The miR-148/152 family contributes to angiogenesis of human pluripotent stem cell- derived endothelial cells by inhibiting MEOX2.

Human pluripotent stem cell-derived endothelial cells (hPSC-ECs) represent a promising source of human ECs urgently needed for the study of cardiovascular disease mechanisms, cell therapy, and drug screening. This study aims to explore the function and regulatory mechanism of the miR-148/152 family consisting of miR-148a, miR-148b, and miR-152 in hPSC-ECs, so as to provide new targets for improving EC function during the above applications. In comparison with the wild-type (WT) group, miR-148/152 family knockout (TKO) significantly reduced the endothelial differentiation efficiency of human embryonic stem cells (hESCs), and impaired the proliferation, migration, and capillary-like tube formatting abilities of their derived ECs (hESC-ECs). Overexpression of miR-152 partially restored the angiogenic capacity of TKO hESC-ECs. Furthermore, the mesenchyme homeobox 2 (MEOX2) was validated as the direct target of miR-148/152 family. MEOX2 knockdown resulted in partial restoration of the angiogenesis ability of TKO hESC-ECs. The Matrigel plug assay further revealed that the in vivo angiogenic capacity of hESC-ECs was impaired by miR-148/152 family knockout, and increased by miR-152 overexpression. Thus, the miR-148/152 family is crucial for maintaining the angiogenesis ability of hPSC-ECs, and might be used as a target to enhance the functional benefit of EC therapy and promote endogenous revascularization.

An engineered dual-functional peptide with high affinity to demineralized dentin enhanced remineralization efficacy in vitro and in vivo.

Dental caries continues to be a major global public health problem. Remineralization of demineralized dentin is regarded as one of the hotspots in the current study in the treatment of dental caries. However, traditional remineralization agents, which usually lack the ability to bind to demineralized dentin collagen, are easily removed by the fluids in the oral cavity, thus decreasing the remineralization efficacy. Non-collagenous proteins (NCPs) have significant effects on the biomineralization of dentin due to their dual high binding capacity to the collagen fibers and minerals. But NCPs are hard to extract, store and use directly. Inspired by the biological behavior of NCPs, in this study, we selected two functional sequences of NCPs to develop a novel and engineered dual-functional peptide (which is referred to as CYP) with collagen-binding and mineral-absorbing capability. The binding ability of CYP to collagen fibers and demineralized dentin was investigated, and the results suggested that CYP was endowed with good binding capacity to demineralized dentin, which could resist the washing of the fluid. In addition, we confirmed that CYP exerted formidable remineralization effects in collagen fibers and demineralized dentin following an in vitro remineralization regimen. Furthermore, the dual functions of CYP with good biocompatibility can simultaneously bind collagen and induce nanocrystal precipitation, thereby significantly absorbing calcium and phosphorus ions to form regenerated minerals for reversing the tooth decay process in the rat caries model. Overall, the dual functional peptide CYP fabricated in this study provides an ideal and smart strategy for dentin remineralization and the treatment of caries.

MEK/ERK/RUNX2 Pathway-Mediated IL-11 Autocrine Promotes the Activation of Müller Glial Cells during Diabetic Retinopathy.

PURPOSE: To uncover the role of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK)/runt-related transcription factor 2 (RUNX2)/interleukin-11 (IL-11) pathway in the activation of Müller glial cells (MGCs) and the breakdown of blood-retina barrier (BRB) during diabetic retinopathy (DR). METHODS: Western blot (WB) detected the activation of MEK/ERK/RUNX2/IL-11 pathway, and quantitative reverse transcription polymerase chain reaction (qRT-PCR) detected IL-11 mRNA levels in high glucose (HG)-exposed MIO-M1 cells. Co-immunoprecipitation (Co-IP) identified the interaction between ERK and RUNX2. Immunofluorescence (IF) measured the co-localization of ERK and RUNX2. Luciferase reporter gene assay identified the transcription activity of IL-11 promoter under HG conditions. Enzyme-linked immunosorbent assay (ELISA) detected IL-11 levels in MIO-M1 cell culture supernatant. WB detected IL-RA protein levels, and Immunofluorescence measured the co-localization of IL-11 and IL-11RA. WB detected MGCs activation marker glial fibrillary acidic protein (GFAP) protein levels. 5-ethynyl-2'-deoxyuridine (EdU) incorporation assay detected the proliferation of MGCs. WB detected the activation of MEK/ERK/RUNX2/IL-11 pathway in streptozotocin (STZ)-induced diabetic mice. ELISA detected IL-11 and IL-11RA levels in mouse retina tissues. QRT-PCR and WB detected tight junction-associated molecules claudin-5, occluding and tight junction protein 1 (ZO-1) mRNA and protein levels in mouse retina tissues, respectively. RESULTS: MEK/ERK/RUNX2/IL-11 pathway was activated in HG-exposed MIO-M1 cells. Additionally, IL-11 bound to IL-11RA on MIO-M1 cells to promote MIO-M1 cell activation and proliferation. In the mouse STZ-induced diabetic model, MEK/ERK/RUNX2/IL-11/IL-11RA pathway was also activated. Finally, the blockade of the pathway mitigated the activation of MGCs and the breakdown of BRB. CONCLUSION: The data suggested that activated MEK/ERK/RUNX2/IL-11/IL-11RA autocrine pathway can promote the activation of MGCs and the breakdown of BRB during DR, implying novel anti-molecular strategies for the treatment of DR.

An Ultra-Stretchable Polyvinyl Alcohol Hydrogel Based on Tannic Acid Modified Aramid Nanofibers for Use as a Strain Sensor.

The mechanical performance is critical for hydrogels that are used as strain sensors. p-Aramid nanofiber (ANF) is preferable as an additive to the reinforce the mechanical performance of a poly(vinyl alcohol) (PVA). However, due to the limited hydrogen bond sites, the preparation of ultra-stretchable, ANF-based hydrogel strain sensor is still a challenge. Herein, we reported an ultra-stretchable PVA hydrogel sensor based on tea stain-inspired ANFs. Due to the presence of numerous phenol groups in the tannic acid (TA) layer, the interaction between PVA and the ANFs was significantly enhanced even though the mass ratio of TA@ANF in the hydrogel was 2.8 wt‱. The tensile breaking modulus of the PVA/TA@ANF/Ag hydrogel sensor was increased from 86 kPa to 326 kPa, and the tensile breaking elongation was increased from 356% to 602%. Meanwhile, the hydrogel became much softer, and no obvious deterioration of the flexibility was observed after repeated use. Moreover, Ag NPs were formed in situ on the surfaces of the ANFs, which imparted the sensor with electrical conductivity. The hydrogel-based strain sensor could be used to detect the joint movements of a finger, an elbow, a wrist, and a knee, respectively. This ultra-stretchable hydrogel described herein was a promising candidate for detecting large-scale motions.

Retinoic acid inhibits the angiogenesis of human embryonic stem cell-derived endothelial cells by activating FBP1-mediated gluconeogenesis.

BACKGROUND: Endothelial cells are located in the inner lumen of blood and lymphatic vessels and exhibit the capacity to form new vessel branches from existing vessels through a process called angiogenesis. This process is energy intensive and tightly regulated. Glycolysis is the main energy source for angiogenesis. Retinoic acid (RA) is an active metabolite of vitamin A and exerts biological effects through its receptor retinoic acid receptor (RAR). In the clinic, RA is used to treat acne vulgaris and acute promyelocytic leukemia. Emerging evidence suggests that RA is involved in the formation of the vasculature; however, its effect on endothelial cell angiogenesis and metabolism is unclear. METHODS: Our study was designed to clarify the abovementioned effect with human embryonic stem cell-derived endothelial cells (hESC-ECs) employed as a cell model. RESULTS: We found that RA inhibits angiogenesis, as manifested by decreased proliferation, migration and sprouting activity. RNA sequencing revealed general suppression of glycometabolism in hESC-ECs in response to RA, consistent with the decreased glycolytic activity and glucose uptake. After screening glycometabolism-related genes, we found that fructose-1,6-bisphosphatase 1 (FBP1), a key rate-limiting enzyme in gluconeogenesis, was significantly upregulated after RA treatment. After silencing or pharmacological inhibition of FBP1 in hESC-ECs, the capacity for angiogenesis was enhanced, and the inhibitory effect of RA was reversed. ChIP-PCR demonstrated that FBP1 is a target gene of RAR. When hESC-ECs were treated with the RAR inhibitor BMS493, FBP1 expression was decreased and the effect of RA on angiogenesis was partially blocked. CONCLUSIONS: The inhibitory role of RA in glycometabolism and angiogenesis is RAR/FBP1 dependent, and FBP1 may be a novel therapeutic target for pathological angiogenesis.

[Meta-analysis of leg length discrepancy after robot-assisted and traditional total hip arthroplasty].

Objective: To systematically evaluate the difference in leg length discrepancy (LLD) between robot-assisted total hip arthroplasty (THA) and traditional THA. Methods: The Cochrane Library, PubMed, Web of Science, EMbase, CNKI, Wanfang, VIP, and CBM databases were searched by computer to collect cohort studies of robot-assisted and traditional THAs from inception to August 11th, 2021. Two researchers independently screened the literature, extracted the data, and evaluated the risk of bias of the included studies. Meta-analysis was performed using RevMan 5.3 software. Results: A total of 10 high-quality cohort studies were included. The results of Meta-analysis showed that compared with traditional THA, LLD after robot-assisted THA was smaller [ MD=-1.64, 95% CI (-2.25, -1.04), P<0.001], Harris scores at 3 and 12 months after operation were higher [ MD=1.50, 95% CI (0.44, 2.57), P=0.006; MD=7.60, 95% CI (2.51, 12.68), P=0.003]. However, the operative time was longer [ MD=8.36, 95% CI (4.56, 12.17), P<0.000 1], and the postoperative acetabular anteversion angle was larger [ MD=1.91, 95% CI (1.43, 2.40), P<0.001]. There was no significant difference in Harris score at 6 months, amnesia index (Forgotten joint score, FJS), postoperative acetabular abduction angle, and incidence of complication between the two groups ( P>0.05). Conclusion: Robot-assisted THA is superior to traditional THA in postoperative LLD.

Crosstalk Between RPE Cells and Choroidal Endothelial Cells via the ANXA1/FPR2/SHP2/NLRP3 Inflammasome/Pyroptosis Axis Promotes Choroidal Neovascularization.

One type of age-related macular degeneration (AMD), neovascular (nAMD), characterized by choroidal neovascularization (CNV), accounts for the majority of the severe central vision impairment associated with AMD. Endothelial cells (ECs) in direct contact with retinal pigment epithelial (RPE) cells are more prone to the pathological angiogenesis involved in CNV. Herein, we investigated the effect of crosstalk between RPE cells and choroidal endothelial cells (CECs) via the ANXA1/FPR2/NLRP3 inflammasome/pyroptosis axis on the development of choroidal neovascularization (CNV) in vitro and in vivo. ANXA1 expression and secretion from ARPE-19 cells were upregulated by hypoxia. FPR2 expression, especially on the plasma membrane, in HCECs was upregulated under hypoxic conditions. ANXA1 secreted from ARPE-19 cells inhibited NLRP3 inflammasome activation and NLRP3 inflammasome-mediated pyroptosis in HCECs by activating the FPR2/SHP2 axis. Moreover, ANXA1 secreted by ARPE-19 cells promoted behaviors of HCECs, including proliferation, migration, and tube formation, by activating the FPR2/SHP2 axis and inhibiting NLRP3 inflammasome-mediated pyroptosis. Inhibiting the upregulated ANXA1/FPR2/SHP2/NLRP3 inflammasome/pyroptosis axis decreased the volume of CNV. Our data suggest that the crosstalk between RPE cells and CECs via the ANXA1/FPR2/NLRP3 inflammasome/pyroptosis axis promotes CNV. This finding could identify a potential target for the prevention and treatment of CNV.

Terraced and 3D Pyramid-Shaped Polymer Single Crystal via Low Temperature-Assisted Microfluidic Technology.

3D pyramidal polymer single crystals provide spatial gradient variations within the crystal molecules, and these variations facilitate the study of the relationship between structure and properties within the molecules of various complexes with anisotropic structures. As described herein, a low-temperature-assisted microfluidic pore channeling approach is proposed to prepare structurally ordered polymer single crystals. A mixture of dichloromethane and dimethyl sulfoxide is used as a prepolymer, and a liquid microfluidic technique is employed to grow the end-functionalized polymers into 3D polymer single crystals. Through the ordered growth of single crystals, a personalized pyramidal pattern with a homogeneous structure is formed. To evaluate the mesh node density, low-temperature growth time and substrate type are also investigated. Rectangular, pyramidal, and dendritic patterns are synthesized via low-temperature single crystal growth. This work shows that low temperature-assisted microfluidics provides a novel means to tune the 3D structure of polymer single crystals.

Geniposide Attenuates Hyperglycemia-Induced Oxidative Stress and Inflammation by Activating the Nrf2 Signaling Pathway in Experimental Diabetic Retinopathy.

Geniposide (GEN) is a natural antioxidant and anti-inflammatory product and plays an important role in the treatment of diabetes and diabetic complications. To explore the biological functions and mechanism of GEN in diabetic retinopathy (DR), we constructed the in vitro and in vivo model of DR by using primary cultured mouse retinal Müller cells and C57BL/6 mice, respectively. We found that GEN inhibited ROS accumulation, NF-κB activation, Müller cell activation, and inflammatory cytokine secretion both in vitro and in vivo, which is probably mediated through the Nrf2 pathway. Exendin (9-39) (EX-9), an antagonist of glucagon-like peptide-1 receptor (GLP-1R), abolished the protective effect of GEN on high glucose- (HG-) induced Müller cells. Additionally, GEN decreased hyperglycemia-induced damage to Müller cells and blood-retinal barrier in the retinas of mice with DR. We demonstrated that GEN was capable of protecting Müller cells and mice from HG-induced oxidative stress and inflammation, which is mostly dependent on the Nrf2 signaling pathway through GLP-1R. GEN may be an effective approach for the treatment of DR.

Celecoxib prevents tumor necrosis factor-α (TNF-α)-induced cellular senescence in human chondrocytes.

Osteoarthritis (OA) is a cartilage degenerative disease commonly observed in the elderly population and significantly impacts the normal life of OA patients. It has been reported that the development of pathological cell senescence in chondrocytes is involved in the pathogenesis of OA. Celecoxib is a common non-steroidal anti-inflammatory drug, and it has been recently reported to exert therapeutic effects on OA. However, its underlying mechanism is still unclear. The present study intends to explore its mechanism and provide fundamental evidence for the application of Celecoxib in the treatment of clinical OA. Tumor necrosis factor-α (TNF-α) was utilized to establish an in vitro model of chondrocytes senescence. The elevated reactive oxygen species (ROS) generation, increased cell cycle arrest in G0/G1 phase, reduced telomerase activity, and upregulated senescence-associatedß-galactosidase (SA-ß-Gal) staining were all observed in TNF-α-treated chondrocytes, which were then dramatically reversed by 10 and 20 µM Celecoxib. In addition, the upregulated DNA damage biomarkers, p-ATM, and p-CHK2, observed in TNF-α-treated chondrocytes were significantly downregulated by 10 and 20 µM Celecoxib. Lastly, the expression level of p21 and p53 was greatly elevated in chondrocytes by stimulation with TNF-α which was then pronouncedly repressed by treatment with Celecoxib. Taken together, our data reveal that Celecoxib ameliorated TNF-α-induced cellular senescence in human chondrocytes.

Shikonin alleviates choroidal neovascularization by inhibiting proangiogenic factor production from infiltrating macrophages.

Choroidal neovascularization (CNV), a feature of neovasular age-related macular degeneration (AMD), acts as a leading cause of vision loss in the elderly. Shikonin (SHI), a natural bioactive compound extracted from Chinese herb radix arnebiae, exerts anti-inflammatory and anti-angiogenic roles and also acts as a potential pyruvate kinase M2 (PKM2) inhibitor in macrophages. The major immune cells macrophages infiltrate the CNV lesions, where the production of pro-angiognic cytokines from macrophage facilitates the development of CNV. PKM2 contributes to the neovascular diseases. In this study, we found that SHI oral gavage alleviated the leakage, area and volume of mouse laser-induced CNV lesion and inhibited macrophage infiltration without ocular cytotoxicity. Moreover, SHI inhibited the secretion of pro-angiogenic cytokine, including basic fibroblast growth factor (FGF2), insulin-like growth factor-1 (IGF1), chemokine (C-C motif) ligand 2 (CCL2), placental growth factor and vascular endothelial growth factor (VEGF), from primary human macrophages by down-regulating PKM2/STAT3/CD163 pathway, indicating a novel potential therapy strategy for CNV.

The P300/XBP1s/Herpud1 axis promotes macrophage M2 polarization and the development of choroidal neovascularization.

Neovascular age-related macular degeneration (AMD), which is characterized by choroidal neovascularization (CNV), leads to vision loss. M2 macrophages produce vascular endothelial growth factor (VEGF), which aggravates CNV formation. The histone acetyltransferase p300 enhances the stability of spliced X-box binding protein 1 (XBP1s) and promotes the transcriptional activity of the XBP1s target gene homocysteine inducible endoplasmic reticulum protein with ubiquitin-like domain 1 (Herpud1). Herpud1 promotes the M2 polarization of macrophages. This study aimed to explore the roles of the p300/XBP1s/Herpud1 axis in the polarization of macrophages and the pathogenesis of CNV. Hypoxia-induced p300 interacted with XBP1s to acetylate XBP1s in RAW264.7 cells. Additionally, hypoxia-induced p300 enhanced the XBP-1s-mediated unfolded protein response (UPR), alleviated the proteasome-dependent degradation of XBP1s and enhanced the transcriptional activity of XBP1s for Herpud1. The hypoxia-induced p300/XBP1s/Herpud1 axis facilitated RAW264.7 cell M2 polarization. Knockdown of the p300/XBP1s/Herpud1 axis in RAW264.7 cells inhibited the proliferation, migration and tube formation of mouse choroidal endothelial cells (MCECs). The p300/XBP1s/Herpud1 axis increased in infiltrating M2-type macrophages in mouse laser-induced CNV lesions. Blockade of the p300/XBP1s/Herpud1 axis inhibited macrophage M2 polarization and alleviated CNV lesions. Our study demonstrated that the p300/XBP1s/Herpud1 axis in infiltrating macrophages increased the M2 polarization of macrophages and the development of CNV.

NAT10 Promotes Osteogenic Differentiation of Mesenchymal Stem Cells by Mediating N4-Acetylcytidine Modification of Gremlin 1.

OBJECTIVE: To investigate the function of NAT10 in mesenchymal stem cell (MSC) osteogenic differentiation and study the mechanism by which NAT10 affects MSC osteogenesis by mediating Gremlin 1 N4-acetylcytidine (ac4C) modification. METHODS: Osteogenic differentiation of MSCs was induced, and the osteogenic ability was evaluated with alizarin red S (ARS) and alkaline phosphatase (ALP) assays. The NAT10 expression level during MSC osteogenesis was measured by western blot (WB). MSCs were transfected with lentiviruses to inhibit (Sh-NAT10) or overexpress NAT10 (Over-NAT10), and the osteogenic differentiation ability was assessed by ARS, ALP, and osteogenic gene marker assays. ß-Catenin, Akt, and Smad signaling pathway component activation levels were assessed, and the expression levels of key Smad signaling pathway molecules were determined by PCR and WB. The Gremlin 1 mRNA ac4C levels were analyzed using RIP-PCR, and the Gremlin 1 mRNA degradation rate was determined. Sh-Gremlin 1 was transfected to further investigate the role of NAT10 and Gremlin 1 in MSC osteogenesis. RESULTS: During MSC osteogenesis, NAT10 expression, ARS staining, and the ALP level gradually increased. Decreasing NAT10 expression inhibited, and increasing NAT10 expression promoted MSC osteogenic differentiation. NAT10 affected the BMP/Smad rather than the Akt and ß-Catenin signaling pathway activation by regulating Gremlin 1 expression. The Gremlin 1 mRNA ac4C level was positively regulated by NAT10, which accelerated Gremlin 1 degradation. Sh-Gremlin 1 abolished the promotive effect of NAT10 on MSC osteogenic differentiation. CONCLUSION: NAT10 positively regulated MSC osteogenic differentiation through accelerating the Gremlin 1 mRNA degradation by increasing its ac4C level. These results may provide new mechanistic insight into MSC osteogenesis and bone metabolism in vivo.

CSF1/CSF1R-mediated Crosstalk Between Choroidal Vascular Endothelial Cells and Macrophages Promotes Choroidal Neovascularization.

Purpose: This study examined the role of the CSF1/CSF1Raxis in the crosstalk between choroidal vascular endothelial cells (CVECs) and macrophages during the formation of choroidal neovascularization (CNV). Methods: Quantitative reverse transcriptase (QRT)-PCR, Western blot and ELISA measured the production and release of CSF1 from human choroidal vascular endothelial cells (HCVECs) under hypoxic conditions. Western blot detected CSF1 released from HCVECs under hypoxic conditions that activated the PI3K/AKT/FOXO1 axis in human macrophages via binding to CSF1R. Transwell migration assay, qRT-PCR, and Western blot detected the effect of CSF1 released from HCVECs on macrophage migration and M2 polarization via the CSF1R/PI3K/AKT/FOXO1 pathway. Incorporation of 5-ethynyl-20-deoxyuridine, transwell migration, and tube formation assays detected the effects of CSF1/CSF1R on the behaviors of HCVECs. Fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA), and immunofluorescence detected the effect of blockade of CSF1/CSF1R on mouse laser-induced CNV. Color fundus photograph, ICGA, and FFA detected CNV lesions in neovascular AMD (nAMD) patients. ELISA detected CSF1 and CSF1R in the aqueous humor of age-related cataract and nAMD patients. Results: CSF1 released from HCVECs under hypoxic conditions activated the PI3K/AKT/FOXO1 axis in human macrophages via binding to CSF1R, promoting macrophage migration and M2 polarization via up-regulation of the CSF1R/PI3K/AKT/FOXO1 pathway. Human macrophages promoted the proliferation, migration, and tube formation of HCVECs in a CSF1/CSFR1-dependent manner under hypoxic conditions. CSF1/CSF1R blockade ameliorated the formation of mouse laser-induced CNV. CSF1 and CSF1R were increased in the aqueous humor of nAMD patients. Conclusions: Our results affirmed the crucial role of CSF1/CSF1R in boosting the formation of CNV and offered potential molecular targets for the treatment of nAMD.

Composite Aramid Membranes with High Strength and pH-Response.

The pH-responsive membrane is a new wastewater treatment technology developed in recent years. In this paper, a novel film with intelligent pH-responsiveness was first prepared by blending functional gates comprised of hydrolyzed aramid nanofibers (HANFs) into aramid nanofiber (ANF) membranes via a vacuum filtration method. Those as-prepared membranes exhibited dual pH-responsive characteristics, which were featured with a negative pH-responsiveness in an acidic environment and a positive pH-responsiveness in basic media. These dual pH-responsive membranes also exhibited a high tensile strength which could still reach 55.74 MPa (even when the HANFs content was as high as 50 wt%), a high decomposition temperature at ~363 °C, and good solvent resistance. The membranes described herein may be promising candidates for a myriad of applications, such as the controlled release of drugs, sensors, sewage treatment, etc.

Melatonin attenuates oxidative stress and inflammation of Müller cells in diabetic retinopathy via activating the Sirt1 pathway.

Oxidative stress and inflammation are important pathogenic factors of diabetic retinopathy (DR). DR remains the most common ocular complication caused by diabetes mellitus (DM) and is the leading cause of visual impairment in working-aged people worldwide. Melatonin has attracted extensive attention due to its potent antioxidant and anti-inflammatory effects. In the present study, melatonin inhibited oxidative stress and inflammation by enhancing the expression and activity of silent information regulator factor 2-related enzyme 1 (Sirt1) both in in vitro and in vivo models of DR, and the Sirt1 inhibitor EX-527 counteracted melatonin-mediated antioxidant and anti-inflammatory effects on Müller cells. Moreover, melatonin enhanced Sirt1 activity through the maternally expressed gene 3 (MEG3)/miR-204 axis, leading to the deacetylation of the Sirt1 target genes forkhead box o1 (Foxo1) and nuclear factor kappa B (NF-κB) subunit p65, eventually contribute to the alleviation of oxidative stress and inflammation. The study revealed that melatonin promotes the Sirt1 pathway, thereby protecting the retina from DM-induced damage.

The HIF-1α/p53/miRNA-34a/Klotho axis in retinal pigment epithelial cells promotes subretinal fibrosis and exacerbates choroidal neovascularization.

Wet age-related macular degeneration (wAMD), characterized by choroidal neovascularization (CNV), is a leading cause of irreversible vision loss among elderly people in developed nations. Subretinal fibrosis, mediated by epithelial-mesenchymal transition (EMT) of retinal pigment epithelium (RPE) cells, leads to unsuccessful anti-vascular endothelial growth factor (VEGF) agent treatments in CNV patients. Under hypoxic conditions, hypoxia-inducible factor-1α (HIF-1α) increases the stability and activation of p53, which activates microRNA-34a (miRNA-34a) transcription to promote fibrosis. Additionally, Klotho is a target gene of miRNA-34a that inhibits fibrosis. This study aimed to explore the role of the HIF-1α/p53/miRNA-34a/Klotho axis in subretinal fibrosis and CNV. Hypoxia-induced HIF-1α promoted p53 stability, phosphorylation and nuclear translocation in ARPE-19 cells (a human RPE cell line). HIF-1α-dependent p53 activation up-regulated miRNA-34a expression in ARPE-19 cells following hypoxia. Moreover, hypoxia-induced p53-dependent miRNA-34a inhibited the expression of Klotho in ARPE-19 cells. Additionally, the HIF-1α/p53/miRNA-34a/Klotho axis facilitated hypoxia-induced EMT in ARPE-19 cells. In vivo, blockade of the HIF-1α/p53/miRNA-34a/Klotho axis alleviated the formation of mouse laser-induced CNV and subretinal fibrosis. In short, the HIF-1α/p53/miRNA-34a/Klotho axis in RPE cells promoted subretinal fibrosis, thus aggravating the formation of CNV.