温阳解郁颗粒调节BDNF/TrkB/ERK信号通路保护皮质酮诱导损伤型海马神经细胞的作用机制研究＊

目的 观察温阳解郁颗粒（Wenyang Jieyu granule，WYJY）对皮质酮（Corticosterone，CORT）诱导损伤型小鼠海马神经细胞（TH22 cell）的保护作用，基于脑源性神经营养因子（Brain derived neurotrophic factor， BDNF）/酪氨酸激酶B（Tyrosine kinase B， TrkB）/细胞外信号调节蛋白激酶（Extra cellular regulated protein kinases， ERK）信号通路探讨WYJY保护海马神经细胞的作用机制。方法 体外构建小鼠海马神经细胞皮质酮诱导损伤模型，以不同浓度的WYJY和氟西汀（Fluoxetine，FXT）含药血清作用于模型细胞，细胞增殖-毒性检测（Cell Counting Kit-8， CCK-8）法分析细胞活性，倒置显微镜下观察给药前后细胞形态结构的改变，采用蛋白免疫印迹法（Western Blot）、实时荧光定量PCR（Quantitative real-time PCR， qPCR）法检测神经细胞内凋亡因子（BCL2-Associated X， Bax）、抗凋亡因子（B-cell lymphoma-2， Bcl-2）、BDNF、Trkb、ERK以及丝氨酸/苏氨酸激酶（Phospho-p90RSK， RSK）、环磷腺苷效应元件结合蛋白（cAMP-response element binding protein， CREB）蛋白表达水平以及相关基因的表达水平。结果 在浓度为459.5 μmol·L^-1的CORT作用24 h后，HT22细胞的活性抑制率达到50%，在此条件作用下细胞形态结构损伤明显，凋亡程度严重，细胞上清中BDNF的含量显著减少（P<0.05），细胞内凋亡相关因子Bax/Bcl-2的比值明显升高（P<0.01），BDNF、Trkb、ERK、RSK、CREB磷酸化蛋白表达水平和mRNA表达水平明显降低（P<0.01）；以5%的浓度为2.85 g·kg^-1的WYJY和10%的FXT含药血清作用于受损的HT22细胞后，HT22细胞存活率明显提升（P<0.01），细胞结构的损伤明显改善，细胞凋亡程度减轻，细胞外BDNF的含量显著升高（P<0.05），细胞内Bax/Bcl-2比值显著下调（P<0.01），BDNF、Trkb、ERK、RSK、CREB磷酸化蛋白表达水平和mRNA表达水平显著提升（P<0.05，P<0.01）。结论 温阳解郁颗粒可有效保护高浓度CORT造成的小鼠海马神经细胞损伤。调控BDNF/Trkb/ERK通路，放大CREB信号传导，影响Bcl-2、BDNF水平，可能是其保护海马神经元，发挥抗抑郁疗效的重要机制。     

Biomarkers of in vivo limbal stem cell function

PurposeTo evaluate in vivo parameters as biomarkers of limbal stem cell function and to establish an objective system that detects and stage limbal stem cell deficiency (LSCD).MethodsA total of 126 patients (172 eyes) with LSCD and 67 normal subjects (99 eyes) were included in this observational cross-sectional comparative study. Slit-lamp biomicroscopy, in vivo laser scanning confocal microscopy (IVCM), and anterior segment optical coherence tomography (AS-OCT) were performed to obtain the following: clinical score, cell morphology score, basal cell density (BCD), central corneal epithelial thickness (CET), limbal epithelial thickness (LET), total corneal nerve fiber length (CNFL), corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), and tortuosity coefficient. Their potential correlations with the severity of LSCD were investigated, and cutoff values were determined.ResultsAn increase clinical score correlated with a decrease in central cornea BCD, limbal BCD, CET, mean LET, maximum LET, CNFL, CNFD, CNBD, and tortuosity coefficient. Regression analyses showed that central cornea BCD, CET and CNFL were the best parameters to differentiate LSCD from normal eyes (Coef = 3.123, 3.379, and 2.223; all p < 0.05). The rank correlation analysis showed a similar outcome between the clinical scores and the central cornea BCD (ρ = 0.79), CET (ρ = 0.82), and CNFL (ρ = 0.71). A comprehensive LSCD grading formula based on a combination of these parameters was established.ConclusionsA comprehensive staging system combining clinical presentation, central cornea BCD, CET, and CNFL is established to accurately and objectively diagnose LSCD and stage its severity.     

La prematuridad: un antecedente de obligada consideración a la hora de valorar el complejo de células ganglionares de la retina

IntroductionPremature children birth and survival is becoming more frequent due to the improvement in obstetric and neonatal care. This makes it increasingly common to find patients with history of preterm birth in ophthalmology clinics, both in pediatric and adult ages. Premature birth can lead to ocular structural changes, being possible to affect the ganglion cell complex (GCC), among other structures, which can be studied using optical coherence tomography.Materials and methodsTo carry out a bibliographic review of the studies that analyze GCC in patients with a history of prematurity compared with patients born at term.ResultsSeveral studies that analyze GCC in patients with a history of prematurity are referenced and their results are studied.ConclusionsIn our clinical practice, knowing the history of prematurity is fundamental in the assessment of GCC measured by optical coherence tomography, since this layer is different in the patients with a history of prematurity compared to patients born at term.