A Preliminary Study Of Etiology In Primary Open–angle Glaucoma

ObjectiveReduced brain-derived neurotrophic factor levels have been discovered in a numberof patho-physiological diseases, and BDNF playsed particularly important a role inneurodegenerative disease pathogenesis.Currently most experts said that glaucoma was aprogressive optic neurodegenerative dioder.Lots of studies showed that BDNF played aprotective role for retinal ganglion cells in glaucomous, and suggested that BDNF also playa key role in POAG pathogenesis.But at home and abroad the BDNF levels of POAGpatients in serum and tears were reported rarely.so we want to undertaken the measurementof it’s serum and tear levels in the attempt to identify a possible link with POAG. BDNFlevels in serum and tears were determined by enzyme-linked immunosorbent assay usingmonoclonal antibodies specific for BDNF.Our aim was looking for pathogenesis of POAGabout BDNF.We also hope to provide more experimental foundation for getting a scientificbiochemical marker in diagnosising early detection of POAG.MethodsWe survey Yanggu POAG family following the declaration of Helsinki and approvalof medical ethics committee.Six patients with POAG in this family were choosed in thistrial.For example Ⅲ-8, Ⅲ-10, Ⅲ-12, Ⅲ-18, Ⅲ-20andⅢ-31. The other14POAG andthose normal volunteers were choosed in outpatient department and eye ward of Liaochengpeople’s hospital form2010to2011. The case group included12men and8womenwithout any apparent ocular or systemic diseas, Average age was45.35years.The controlgroup included13men and12women, Average age was44.9years. The tear and peripheral venous blood samples were collected form9:00am to11:00am. We extracted serum aftercentrifugation of blood at room temperature,.Tears were collected using small-volume(20μl)glass microcapillary tubes under16X slit lamp magnification. Nonreflex tears werecollected from the inferior tear prism without contact with the lower lid until a total of10μl.The extracted serum and tears was stored at-80°C until processing.Then usingenzyme-linked immunosorbent assay monoclonal antibodies specific for BDNF.ResultsThe two independent samples t test in spss13.0software was used in these resultsanalysis The mean level of BDNF detected in the serum of the Yanggu POAG was2.78±2.1ng/ml and the sending out POAG was3.10±1.72ng/ml(P=0.727＞0.05). Themean level of BDNF detected in the tear of the Yanggu POAG was0.63±0.13ng/ml andthe sending out POAG was0.73±0.22ng/ml(P=0.299＞0.05).The BDNF levels in serum ofthe case group were3.01±1.79ng/mL and the normal subjects was3.59±3.46)ng/mL(P=0.51＞0.05). The BDNF in the tears of POAG patients was significantly less thannormal((0.70±0.2)ng/ml VS(0.89±0.32)ng/ml;P=0.03＜0.05).ConclusionsBDNF in POAG genetic genealogy had the limited function.There should have somegenes mutations.We found that BDNF protein levels in tear was reliably different betweengroups, but in serum not.We concluded the level of BDNF in human tear was informativeor reliable as POAG biomarkers. ObjectiveGlaucoma is a pathologic condition in which there is a progressive loss of retinalganglion cells, specific visual field deficit, and a characteristic excavative atrophy of theoptic nerve.Glaucoma is the major cause of irreversible blindness worldwide. Primaryopen-angle glaucoma is the most prevalent form of glaucoma. The extracellular matrix ofthe trabecular meshwork is thought to be important inregulating intraocular pressure inglaucomatous eyes.Now studies suggest that MiR-29b negatively regulates the expressionof multiple genes involved in the synthesis and deposition of ECM in trabecular meshworkcells. Downregulation of miR-29b might contribute to increased expression of severalECM genes under chronic oxidative stress conditions. The balance between the activationof ECM production inducedby oxidative stress and the protective effects of miR-29b couldbe a relevant factor in understanding how oxidative damagemay lead to increaseddeposition of ECM in the trabecular meshwork and contribute to the elevation ofintraocular pressure in glaucoma.The serum miRNA is related POAG in our world. Toidentify miR-29b differentially expressed in human POAG patients to provide a basis forfurther study of the role of miRNAs in the pathogenesis of POAG. It will be used forbecoming POAG early diagnosis biomarkers, progression and gene therapy to providetheory and experiment foundation.MethodsThe5sending out POAG and those normal volunteers were choosed in my firststudy.The case group included3men and2women without any apparent ocular or systemicdiseas, Average age was50.2years.The control group included3men and2women,Average age was48.6years. The peripheral venous blood samples were collected formaking serum after centrifugation10mins.Changes in expression in miR-29b wereanalyzed by qRT-PCR.ResultsMicroRNA-29b in4of the5sending out POAG patients are down regulation. Theexpression of miR-29b in the sending out POAG is less than the control group,about0.152times,P=0.028,and the differences is statistically significant.Conclusions The expression of miR-29b in the sending out POAG was down regulation comparingwith the normal group. It suggest that miR-29b may plays an important role inpathogenesis of POAG except genic mutations.The down regulation of miR-29b increasethe extracellular matrix of human trabecular meshwork.The results provide a new researchdirection in paehogenesia of POAG and a new target for POAG treatment.