Epsin1-mediated exosomal sorting of Dll4 modulates the tubular-macrophage crosstalk in diabetic nephropathy.

Tubular epithelial cells (TECs) play critical roles in the development of diabetic nephropathy (DN), and can activate macrophages through the secretion of exosomes. However, the mechanism(s) of TEC-exosomes in macrophage activation under DN remains unknown. By mass spectrometry, 1,644 differentially expressed proteins, especially Dll4, were detected in the urine exosomes of DN patients compared with controls, which was confirmed by western blot assay. Elevated Epsin1 and Dll4/N1ICD expression was observed in kidney tissues in both DN patients and db/db mice and was positively associated with tubulointerstitial damage. Exosomes from high glucose (HG)-treated tubular cells (HK-2) with Epsin1 knockdown (KD) ameliorated macrophage activation, TNF-α, and IL-6 expression, and tubulointerstitial damage in C57BL/6 mice in vivo. In an in vitro study, enriched Dll4 was confirmed in HK-2 cells stimulated with HG, which was captured by THP-1 cells and promoted M1 macrophage activation. In addition, Epsin1 modulated the content of Dll4 in TEC-exosomes stimulated with HG. TEC-exosomes with Epsin1-KD significantly inhibited N1ICD activation and iNOS expression in THP-1 cells compared with incubation with HG alone. These findings suggested that Epsin1 could modulate tubular-macrophage crosstalk in DN by mediating exosomal sorting of Dll4 and Notch1 activation.

Metagenome Sequencing Reveals the Microbiome of Aedes albopictus and Its Possible Relationship With Dengue Virus Susceptibility.

Dengue fever virus (DENV) is a mosquito-borne flavivirus that poses a serious risk to human health. Aedes albopictus is a widely distributed vector of dengue fever in China. Based on the impact of physiological activity, the microbiome in A. albopictus will provide a novel environment-friendly approach to control DENV transmission. We performed metagenomic sequencing on A. albopictus before and after exposure to DENV blood meal to detect microbiome variation of A. albopictus with different susceptibilities to DENV. The dominant phyla in A. albopictus microbiome were Proteobacteria and Ascomycota, and the dominant genera were Aspergillus and Metarhizium. Gammaproteobacteria bacterium, Lactobacillus harbinensis, and Neurospora crassa differed significantly after DENV infection. There were 15 different microorganisms found to be involved in mosquito immunity and metabolism, such as Alphaproteobacteria bacterium, Methyloglobulus morosus, and Shigella sonnei, which might have an impact on the DENV susceptibility of A. albopictus. It was hypothesized that the lack of specific bacteria may lead to increased susceptibility of A. albopictus to DENV. Interventions in the microbiome composition or specific bacteria of A. albopictus may affect the susceptibility to DENV and control the mosquito-borne diseases efficiently.

The Runx1/Notch1 Signaling Pathway Participates in M1/M2 Microglia Polarization in a Mouse Model of Temporal Lobe Epilepsy and in BV-2 Cells.

Microglial activation and phenotypic shift play vital roles in many neurological diseases. Runt-related transcription factor-1 (Runx1), which is localized on microglia, inhibits amoeboid microglial proliferation. Preliminary data have indicated that the interaction of Runx1 with the Notch1 pathway affects the hemogenic endothelial cell shift. However, little is known about the effect of Runx1 and the Notch1 signaling pathway on the phenotypic shift of microglia during neuroinflammation, especially in temporal lobe epilepsy (TLE). A mouse model of TLE induced by pilocarpine and the murine microglia cell line BV-2 were used in this study. The proportion of microglia was analyzed using flow cytometry. Western blot (WB) analysis and quantitative real-time polymerase chain reaction were used to analyze protein and gene transcript levels, respectively. Immunohistochemistry was used to show the distribution of Runx1. In the present study, we first found that in a male mouse model of TLE induced by pilocarpine, flow cytometry revealed a time-dependent M2-to-M1 microglial transition after status epilepticus. The dynamic expression patterns of Runx1 and the downstream Notch1/Jagged1/Hes5 signaling pathway molecules in the epileptic hippocampus were determined. Next, Runx1 knockdown by small interfering RNA in BV-2 cells strongly promoted an M2-to-M1 microglial phenotype shift and inhibited Notch1/Jagged1/Hes5 pathway expression. In conclusion, Runx1 may play a critical role in the M2-to-M1 microglial phenotype shift via the Notch1 signaling pathway during epileptogenesis in a TLE mouse model and in BV-2 cells.

[Retina penetration of subconjunctival ranibizumab injection in the rabbit eye].

OBJECTIVE: To investigate whether ranibizumab can penetrate into the retina after subconjunctival injection in a rabbit model. METHODS: Experimental study. Fifty-six New Zealand rabbits were randomly divided into four groups: control group (3), saline subconjunctival injection group (3), ranibizumab intravitreal injection group (25) and ranibizumab subconjunctival injection group (25). Each rabbit received single injection in right eye. Ranibizumab's location and concentrations in the retina and aqueous humor were determined by immunofluorescence staining and ELISA at 1, 2, 4, 8, 12 weeks after injection. The comparison of ranibizumab concentration data was analyzed by t-test. RESULTS: The concentrations of aqueous humor in intravitreal injection group, determined by ELISA, were (389.67 ± 22.55), (319.33 ± 17.93), (22.67 ± 3.06), (9.67 ± 1.53) and (7.33 ± 2.18) mg/L at 1, 2, 4, 8, 12 weeks respectively. Concentrations of subconjunctival injection group were (53.67 ± 3.21), (12.67 ± 3.06), (8.33 ± 1.53), (2.66 ± 2.08) mg/L at 1,2,4,8 weeks and had a statistical difference compared with intravitreal injection group at each time point (t = 32.96, 38.39, 7.67, 11.07, P < 0.05). But there was no detection at 12 weeks. Similar in retina immunofluorescence staining results, the ranibizumab positive signals were detected in all the time points except the last one in subconjunctival injection group. CONCLUSION: Subconjunctival ranibizumab injection may be able to penetrate into retina.

[Curative effect of pemetrexed on the treatment of relapsed primary central nervous system lymphoma].

OBJECTIVE: To explore the efficacy and safety of pemetrexed in the treatment of relapsed primary central nervous system lymphoma (PCNSL). METHODS: Seven cases with relapsed PCNSL admitted in our hospital between August 2012 and August 2013 were retrospectively reviewed. RESULTS: Of the 7 relapsed cases, ectopic recurrence occurred in 3, in situ recurrence in 3 and leptomeningeal metastasis in 1. Patients with relapsed PCNSL were administered with high-dose pemetrexed (900 mg/m²) once for every 3 weeks and supplemented with folic acid and vitamin B12. Complete remission was obtained in 2 patients, partial remission in 3 patients and progressive disease in 2. The overall response rate was 71.4% (5/7). The main adverse reactions were myelosuppression and gastrointestinal reaction. CONCLUSION: Treatment of relapsed PCNSL is difficult, and its prognosis is very poor. Pemetrexed therapy is a meaningful trial.