Objective:To investigate the role and underlying mechanism of protein arginine methyltransferase 1 (PRMT1) and its inhibitor in alkali burn-induced corneal neovascularization (CNV).Methods:Seventy-two SPF-grade C57BL/6 mice were randomly divided into a normal group and 1 day post-modeling, 4 days post-modeling, and 7 days post-modeling groups to establish an alkali burn-induced CNV model and determine the optimal time point for analysis.Another 90 mice were randomly assigned to five groups: alkali burn group, dimethyl sulfoxide (DMSO) group, PRMT1 inhibitor group, fibroblast growth factor 2 (FGF2) inhibitor group, and PRMT1 inhibitor combined with FGF2 group to evaluate the role of PRMT1 in CNV.Human umbilical vein endothelial cells (HUVECs) and murine macrophage-like RAW264.7 cells were used to establish a hypoxia/reoxygenation (H/R)-induced in vitro model to mimic the ischemic microenvironment.Cells were assigned to the following groups: control group, H/R group, H/R+ DMSO group, H/R+ si-NC group, H/R+ si-PRMT1 group, H/R+ si-FGF2 group, H/R+ PRMT1 inhibitor group, and H/R+ PRMT1 inhibitor+ FGF2 group.Corneal opacity and CNV areas were assessed by slit-lamp microscopy.Corneal structural changes and inflammatory cell count were determined by hematoxylin and eosin staining.PRMT1-positive cell count was determined by immunohistochemistry and the expression of PRMT1, CD31, vascular endothelial growth factor (VEGF), F4/80, CD206, and inducible nitric oxide synthase (iNOS) was assessed by immunofluorescence staining.The expression levels of macrophage markers, including F4/80, iNOS, CD206, interleukin-10 (IL-10), and arginase-1 (Arg-1), were quantified by real-time quantitative PCR and Western blot.Cell proliferation, migration, and angiogenic capacity were evaluated by functional assays including the CCK-8 assay, wound healing assay, Transwell migration assay, and tube formation assay.The research process followed the relevant regulations of the Visual and Ophthalmology Association, and the research plan was approved by the Laboratory Animal Committee of Wuhan University (No.20220504A). Results:Compared with the normal group, the 7 days post-modeling group showed significantly increased corneal opacity scores and CNV area, upregulated VEGF expression, and increased inflammatory cells (all P<0.05).The number of PRMT1-positive cells in the alkali burn group was (39.67±3.51) cells/visual field, which was significantly higher than (3.33±0.58) cells/visual field in the normal group ( t=17.68, P<0.01).Both mRNA and protein expression levels of PRMT1 and FGF2 were significantly elevated in the alkali burn group compared with the normal group (all P<0.01).Compared with the alkali burn group, the PRMT1 inhibitor group showed reduced corneal opacity scores, decreased CNV area, fewer inflammatory cells, and lower expression levels of PRMT1, FGF2, VEGF, Arg-1, IL-10 proteins, as well as CD206 mRNA (all P<0.05).Cell viability, migration distance, migration number, and tubes formed were significantly increased in the H/R group compared with the control group, significantly reduced in the H/R+ si-PRMT1 and H/R+ PRMT1 inhibitor groups compared with the H/R group and significantly increased in H/R+ PRMT1 inhibitor+ FGF2 group than in H/R+ PRMT1 inhibitor group (all P<0.05).Compared with the H/R group, the H/R+ PRMT1 inhibitor group exhibited reduced expression of FGF2, VEGFA, p-PI3K, and p-Akt, while those were upregulated in the H/R+ PRMT1 inhibitor+ FGF2 group compared with the H/R+ PRMT1 inhibitor group (all P<0.05).The proportions of CD206-positive cells in the H/R, H/R+ DMSO, H/R+ PRMT1 inhibitor, and H/R+ PRMT1 inhibitor+ FGF2 groups were all significantly higher than those in the control group, and significantly higher in the H/R, H/R+ DMSO, and H/R+ PRMT1 inhibitor+ FGF2 groups compared with the H/R+ PRMT1 inhibitor group (all P<0.05).Compared with the alkali burn group, the FGF2 inhibitor group, PRMT1 inhibitor group, and PRMT1 inhibitor+ FGF2 group all showed reduced corneal opacity scores, CNV area, and decreased number of VEGFA-, CD206-, and F4/80-positive cells, with the above indicators being lower in the PRMT1 inhibitor group compared with the FGF2 inhibitor and PRMT1 inhibitor+ FGF2 groups and higher in PRMT1 inhibitor+ FGF2 group than in the FGF2 inhibitor group (all P<0.05).Compared with the alkali burn group, the PRMT1 inhibitor group had decreased protein expression levels of FGF2, p-PI3K, p-Akt, CD31, VEGFA and Arg-1, with higher protein expression levels in the PRMT1 inhibitor+ FGF2 group than in the PRMT1 inhibitor group (all P<0.05). Conclusions:PRMT1 may regulate macrophage activation and anti-inflammatory polarization via the FGF2/PI3K/Akt signaling pathway, thereby promoting the occurrence and development of CNV.Targeted inhibition of PRMT1 may serve as an effective therapeutic strategy for CNV.

Objective:To investigate the role and underlying mechanism of protein arginine methyltransferase 1 (PRMT1) and its inhibitor in alkali burn-induced corneal neovascularization (CNV).Methods:Seventy-two SPF-grade C57BL/6 mice were randomly divided into a normal group and 1 day post-modeling, 4 days post-modeling, and 7 days post-modeling groups to establish an alkali burn-induced CNV model and determine the optimal time point for analysis.Another 90 mice were randomly assigned to five groups: alkali burn group, dimethyl sulfoxide (DMSO) group, PRMT1 inhibitor group, fibroblast growth factor 2 (FGF2) inhibitor group, and PRMT1 inhibitor combined with FGF2 group to evaluate the role of PRMT1 in CNV.Human umbilical vein endothelial cells (HUVECs) and murine macrophage-like RAW264.7 cells were used to establish a hypoxia/reoxygenation (H/R)-induced in vitro model to mimic the ischemic microenvironment.Cells were assigned to the following groups: control group, H/R group, H/R+ DMSO group, H/R+ si-NC group, H/R+ si-PRMT1 group, H/R+ si-FGF2 group, H/R+ PRMT1 inhibitor group, and H/R+ PRMT1 inhibitor+ FGF2 group.Corneal opacity and CNV areas were assessed by slit-lamp microscopy.Corneal structural changes and inflammatory cell count were determined by hematoxylin and eosin staining.PRMT1-positive cell count was determined by immunohistochemistry and the expression of PRMT1, CD31, vascular endothelial growth factor (VEGF), F4/80, CD206, and inducible nitric oxide synthase (iNOS) was assessed by immunofluorescence staining.The expression levels of macrophage markers, including F4/80, iNOS, CD206, interleukin-10 (IL-10), and arginase-1 (Arg-1), were quantified by real-time quantitative PCR and Western blot.Cell proliferation, migration, and angiogenic capacity were evaluated by functional assays including the CCK-8 assay, wound healing assay, Transwell migration assay, and tube formation assay.The research process followed the relevant regulations of the Visual and Ophthalmology Association, and the research plan was approved by the Laboratory Animal Committee of Wuhan University (No.20220504A). Results:Compared with the normal group, the 7 days post-modeling group showed significantly increased corneal opacity scores and CNV area, upregulated VEGF expression, and increased inflammatory cells (all P<0.05).The number of PRMT1-positive cells in the alkali burn group was (39.67±3.51) cells/visual field, which was significantly higher than (3.33±0.58) cells/visual field in the normal group ( t=17.68, P<0.01).Both mRNA and protein expression levels of PRMT1 and FGF2 were significantly elevated in the alkali burn group compared with the normal group (all P<0.01).Compared with the alkali burn group, the PRMT1 inhibitor group showed reduced corneal opacity scores, decreased CNV area, fewer inflammatory cells, and lower expression levels of PRMT1, FGF2, VEGF, Arg-1, IL-10 proteins, as well as CD206 mRNA (all P<0.05).Cell viability, migration distance, migration number, and tubes formed were significantly increased in the H/R group compared with the control group, significantly reduced in the H/R+ si-PRMT1 and H/R+ PRMT1 inhibitor groups compared with the H/R group and significantly increased in H/R+ PRMT1 inhibitor+ FGF2 group than in H/R+ PRMT1 inhibitor group (all P<0.05).Compared with the H/R group, the H/R+ PRMT1 inhibitor group exhibited reduced expression of FGF2, VEGFA, p-PI3K, and p-Akt, while those were upregulated in the H/R+ PRMT1 inhibitor+ FGF2 group compared with the H/R+ PRMT1 inhibitor group (all P<0.05).The proportions of CD206-positive cells in the H/R, H/R+ DMSO, H/R+ PRMT1 inhibitor, and H/R+ PRMT1 inhibitor+ FGF2 groups were all significantly higher than those in the control group, and significantly higher in the H/R, H/R+ DMSO, and H/R+ PRMT1 inhibitor+ FGF2 groups compared with the H/R+ PRMT1 inhibitor group (all P<0.05).Compared with the alkali burn group, the FGF2 inhibitor group, PRMT1 inhibitor group, and PRMT1 inhibitor+ FGF2 group all showed reduced corneal opacity scores, CNV area, and decreased number of VEGFA-, CD206-, and F4/80-positive cells, with the above indicators being lower in the PRMT1 inhibitor group compared with the FGF2 inhibitor and PRMT1 inhibitor+ FGF2 groups and higher in PRMT1 inhibitor+ FGF2 group than in the FGF2 inhibitor group (all P<0.05).Compared with the alkali burn group, the PRMT1 inhibitor group had decreased protein expression levels of FGF2, p-PI3K, p-Akt, CD31, VEGFA and Arg-1, with higher protein expression levels in the PRMT1 inhibitor+ FGF2 group than in the PRMT1 inhibitor group (all P<0.05). Conclusions:PRMT1 may regulate macrophage activation and anti-inflammatory polarization via the FGF2/PI3K/Akt signaling pathway, thereby promoting the occurrence and development of CNV.Targeted inhibition of PRMT1 may serve as an effective therapeutic strategy for CNV.

Objective To evaluate the relationship between protein kinase B (AKT) and protein kinase (PKCθ) and morphine-induced inhibition of differentiation of T helper (Th) cells.Methods Peripheral venous blood samples were taken from 20 healthy volunteers..Peripheral blood mononuclear cells (PBMCs) were extracted by density gradient centrifugation method.CD4+ T lymphocytes extracted were purified by magnetic bead separation.CD4+ T lymphocytes were randomly assigned into 5 groups (n =3 each) using a random number table.CD4 + T lymphocytes were incubated routinely in group C.CD4 + T lymphocytes were incubated in the presence of PMA 25 ng/ml + ionomycin 1 μg/ml (group PI),PMA 25 ng/ml + ionomycin 1 μμg/ml + morphine 50 μμg/ml (group M),or PMA 25 ng/ml + ionomycin 1 μμg/ml + morphine 50 μg/ml + naloxone 50 μμg/ml (group N).The cells were incubated for 4 h in the incubator containing 5％ CO2 at 37 ℃.The expression of interferon (IFN)-γ and interleukin-4 (IL-4) was detected by flow cytometry.The expression of IFN-γ and IL-4 was used to reflect the percentage of Th1 and Th2 cells,respectively.The ratio of Th1/Th2 was calculated.The expression of AKT,phosphorylated AKT (p-AKT),PKCθ and phosphorylated PKCθ (p-PKCθ) was detected by Western blot,and the ratio of p-AKT/AKT and p-PKCθ/PKCθ was calculated to reflect the activities of AKT and PKCθ,respectively.Results Compared with group C,the percentage of Th1 and Th2 cells and ratio of Th1/Th2 were significantly increased in PI,M and N groups,the activities of AKT and PKCθ were increased in PI and N groups,and the activity of PKCθ was increased in group M (P ＜ 0.05).Compared with group PI,the percentage of Th1 cells,ratio of Th1/Th2 and activity of AKT were significantly decreased in group M,the ratio of Th1/Th2 was decreased in group N (P ＜0.05),and no significant change in the activity of PKCθ was found in M and N groups (P ＞ 0.05).Compared with group M,the percentage of Th1 cells,ratio of Th1/Th2 and activity of AKT were significantly increased (P ＜ 0.05),while no significant change in the activity of PKCθ was observed in group N (P ＞ 0.05).Conclusion The mechanism by which morphine inhibits the differentiation of Th cells through activating opioid receptors is related to inhibition of AKT activation,but not related to PKCθ.

Objective To evaluate the relationship between GATA-3 and T-bet and inhibition of the differentiation of human T helper cells by morphine.Methods Ten healthy volunteers,aged 20-50 yr,weighing 50-70 kg,were enrolled in the study.Peripheral venous blood samples were taken in the early morning.Peripheral blood mononuclear cells (PBMCs) were isolated and assigned into 5 groups (n=10 each).PBMCs were incubated routinely (group C).PBMCs were incubated in the presence of PMA and ionomycin (group P),morphine 50 μg/ml (group M),morphine 50 μg/ml + naloxone 50 μg/ml (group MN) or naloxone 50μg/ml (group N),and were then stimulated with PMA and ionomycin for another 4 h.The percentage of Th1 and Th2 cells was detected by flow cytometry.The Th1/Th2 ratio was calculated.Interferon (IFN)-γ and interleukin (IL)-4 concentrations in the supematant were determined using ELISA.The activities of GATA-3 and T-bet were analyzed by EMSA.Results Compared with group P,the percentage of Th1 and Th2 cells,Th1/Th2 ratio,IFN-γand IL-4 concentrations in the supernatant,and GATA-3 and T-bet activities were significantly decreased in group M,the percentage of Th1 cells,Th1/Th2 ratio,and IFN-γ concentration in the supernatant were significantly decreased in group MN (P ＜ 0.05 or 0.01).Compared with group M,the percentage of Th1 and Th2 cells,Th1/Th2 ratio,IFN-γ and IL-4 concentrations in the supernatant,and GATA-3 and T-bet activities were significantly increased in group MN (P ＜ 0.05 or 0.01).There was no significant difference in the indexes mentioned above between groups N and C (P ＞ 0.05).Conclusion Morphine inhibits the differentiation of human T helper cells by activating opioid receptors,which may be related to the inhibition of GATA-3 and T-bet activities.

AIM　To study the electrochemical behavior of ofloxacin at Pt/GC ion implantation modified electrode. METHODS　With Pt/GC ion implantation modified electrode as working electrode, the behavior of ofloxacin was studied by voltammetry in 0.40 mol*L-1 KCl solution. RESULTS　A sensitive reductive peak of ofloxacin was obtained by linear sweep voltammetry. The peak potential was -1.35 V (vs SCE). The peak current was proportional to the concentration of ofloxacin over the range of 1.0×10-6-3.0×10-5 mol*L-1 with the detection limit of 5.0×10-7 mol*L-1. The behavior of reduction wave was studied and applied to determination of ofloxacin in tablets. CONCLUSION　The reduction process was irreversible. The element composition, atomicity form and depth of distribution at the surface of Pt/GC electrode were determined by Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) and scannig electron microscope (SEM). The catalysis behavior and reaction mechanism at Pt/GC modified electrode was also studied.