scholarly journals Effect of Exogenous Alpha-B Crystallin on the Structures and Functions of Trabecular Meshwork Cells

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Hui Xu ◽  
Li Zhu ◽  
Yu Wang ◽  
Yongzhen Bao

Purpose. Secondary open-angle glaucoma may develop as a postoperative complication of early childhood cataract surgery. Its mechanism is poorly understood. Surgical removal of cataracts is typically incomplete, and we estimate that this disease is associated with alpha-B crystallin (CRYAB) secreted from the retained lens material. This study, for the first time, focused on the role of CRYAB in undesired changes of the structures and functions in trabecular meshwork (TM) cells.Methods. Cell proliferation and migration were assessed using a cell counting kit-8 (CCK8) and transwell assay analysis, respectively. Immunofluorescence (IF), quantitative real-time PCR (Rt-qPCR), and Western blot were performed to determine the effect of CRYAB on F-actin, tight junctions, and the expression of epithelial to mesenchymal transition- (EMT-) associated proteins in TM cells.Results. CRYAB promoted proliferation (p<0.0001), migration (p<0.001), and F-actin reorganization in TM cells. There were statistically significant increases in the mRNA and protein levels of zo-1, cadherin-N, and vimentin (allp<0.0001) and cadherin-E decreased (p<0.0001) and the mRNA level of claudin-1 increased (p<0.0001) compared to those of the control group.Conclusion. All of the changes in structures and functions first observed in the TM cells after exposure to CRYAB resembled alterations seen in primary open-angle glaucoma, suggesting that CRYAB might be related to the pathogenesis of secondary open-angle glaucoma after congenital cataract surgery.

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ajay Ashok ◽  
Min H. Kang ◽  
Aaron S. Wise ◽  
P. Pattabiraman ◽  
William M. Johnson ◽  
...  

Abstract Endothelial-to-mesenchyme-like transition (Endo-MT) of trabecular meshwork (TM) cells is known to be associated with primary open angle glaucoma (POAG). Here, we investigated whether the prion protein (PrPC), a neuronal protein known to modulate epithelial-to-mesenchymal transition in a variety of cell types, is expressed in the TM, and plays a similar role at this site. Using a combination of primary human TM cells and human, bovine, and PrP-knock-out (PrP−/−) mouse models, we demonstrate that PrPC is expressed in the TM of all three species, including endothelial cells lining the Schlemm’s canal. Silencing of PrPC in primary human TM cells induces aggregation of β1-integrin and upregulation of α-smooth muscle actin, fibronectin, collagen 1A, vimentin, and laminin, suggestive of transition to a mesenchyme-like phenotype. Remarkably, intraocular pressure is significantly elevated in PrP−/− mice relative to wild-type controls, suggesting reduced pliability of the extracellular matrix and increased resistance to aqueous outflow in the absence of PrPC. Since PrPC is cleaved by members of the disintegrin and matrix-metalloprotease family that are increased in the aqueous humor of POAG arising from a variety of conditions, it is likely that concomitant cleavage of PrPC exaggerates and confounds the pathology by inducing Endo-MT-like changes in the TM.


2019 ◽  
Vol 72 (7-8) ◽  
pp. 202-208
Author(s):  
Bojana Markic ◽  
Milka Mavija ◽  
Sasa Smoljanovic-Skocic ◽  
Sanela-Sanja Burgic

Introduction. It has been recognized that cataract surgery leads to a reduction of intraocular pressure, both in healthy and in glaucoma patients. This prospective interventional clinical study aimed to investigate the effects of cataract surgery on intraocular pressure and its short- and long-term fluctuations in medically controlled primary open-angle glaucoma patients and non-glaucomatous patients. Material and Methods. Two groups of 31 patients (31 eyes) were studied. The observed group included patients with glaucoma and cataract, and the control group included patients with senile cataract only. The intraocular pressure was measured three times daily pre- and at 1, 3 and 6 months postoperatively. Results. In both groups, a significant postoperative reduction in both mean and maximum intraocular pressure. Six months after surgery, in the observed group the average and maximum intraocular pressure reduction levels were -2.73 ? 1.91 mmHg and -3.16 ? 2.19 mmHg, and -2.26 ? 1.71 mmHg and -2.53 ? 1.70 mmHg in the control group. In the observed group, at 3 and 6 months after surgery, a significant reduction in short-term fluctuations was observed. Six months after surgery, short-term fluctuations decreased by -1.04 ? 2.20 mmHg compared to preoperative. Postoperatively, in the observed group, long-term fluctuations of average and maximum intraocular pressure were 2.69 ? 2.15 mmHg and 2.88 ? 2.22 mmHg, respectively, and in the controls they were 2.02 ? 1.28 mmHg and 2.42 ? 1.47 mmHg, showing no significant differences between groups. Conclusion. In patients with primary open-angle glaucoma, cataract surgery results in a statistically significant reduction in both average and maximum intraocular pressure as well as of short-term fluctuations.


2015 ◽  
Vol 2015 ◽  
pp. 1-4 ◽  
Author(s):  
Antonio Maria Fea ◽  
Giulia Consolandi ◽  
Marta Zola ◽  
Giulia Pignata ◽  
Paola Cannizzo ◽  
...  

Purpose. To report the long-term follow-up results in patients with cataract and primary open-angle glaucoma (POAG) randomly assigned to cataract surgery combined with micro-bypass stent implantation or phacoemulsification alone.Methods. 36 subjects with cataract and POAG were randomized in a 1 : 2 ratio to either iStent implantation and cataract surgery (combined group) or cataract surgery alone (control group). 24 subjects agreed to be evaluated again 48 months after surgery. Patients returned one month later for unmedicated washout assessment.Results. At the long-term follow-up visit we reported a mean IOP of 15,9 ± 2,3 mmHg in the iStent group and 17 ± 2,5 mmHg in the control group (p=NS). After washout, a 14,2% between group difference in favour of the combined group was statistically significant (p=0,02) for mean IOP reduction. A significant reduction in the mean number of medications was observed in both groups compared to baseline values (p=0,005in the combined group andp=0,01in the control group).Conclusion. Patients in the combined group maintained low IOP levels after long-term follow-up. Cataract surgery alone showed a loss of efficacy in controlling IOP over time. Both treatments reduced the number of ocular hypotensive medications prescribed. This trial is registered with:NCT00847158.


Author(s):  
E. N. Simakova ◽  
O. V. Stenkova

Introduction. Glaucoma is one of the most significant eye diseases. It is often diagnosed, not always amenable to therapy, and can lead to a complete loss of visual functions. In recent years, the method of osteopathic correction has become widespread as one of the effective methods of treatment and rehabilitation of patients with pathologies of various body systems. In the pathogenesis of glaucoma, it is customary to distinguish a dystrophic concept, which considers primary open-angle glaucoma as a result of dystrophic changes in the connective tissue, as well as in the endothelial lining of the trabeculae and Schlemm′s canal, especially destructive changes in mitochondria and the alteration of their functional activity. A vascular concept is also distinguished. According to this concept, the central link in the pathogenesis of glaucoma is circulatory disorder in the ciliary vessels, ocular artery, and major vessels of the head and neck, it can be assumed that osteopathic correction in the treatment of patients with open-angle glaucoma will be pathogenetically substantiated and will have a positive effect on intraocular pressure and trophicity of the optic nerve. The goal of research — to study the influence of in osteopathic correction on the nature of unoperated glaucoma (stage IIA) and to substantiate the possibility of using osteopathic correction in the complex treatment of patients with this pathology.Materials and methods. A prospective controlled randomized study was conducted at 52 city polyclinics, branch 3, Moscow, from January 2018 to January 2019. 40 patients (70 eyes) aged 50 to 75 years with primary open-angle glaucoma IIA stage were examined. At this stage of the disease, patients most often seek medical care and the issue of conservative management is primarily considered. All patients were divided into two groups of 20 people: the main group and the control group. The treatment in the main group included hypotensive drug therapy and osteopathic correction. Patients of the control group received only drug therapy. All patients underwent ophthalmic (visometry, tonometry, perimetry) and osteopathic examination twice: before the treatment and after 3 months.Results. For patients with primary open-angle IIA non-operated glaucoma, regional (most often regions of the head, neck, dura mater) and local (abdominal diaphragm, iliac bones, hip and knee joints) somatic dysfunctions were the most typical. In the main group a statistically significant decrease in the frequency and severity of dysfunctions at all levels was stated. Also, in patients receiving osteopathic correction, a significant decrease in the level of intraocular pressure and perimetric indices was noted. In patients of the control group, no reliable changes in these indicators were obtained.Conclusion. The results obtained indicate that osteopathic correction is clinically effective in the complex treatment of patients with primary open-angle II A glaucoma.


2021 ◽  
Vol 10 (3) ◽  
pp. 401
Author(s):  
Tomoki Sato ◽  
Takahiro Kawaji

We evaluated the effects of ripasudil on the distal aqueous outflow tract in patients with open-angle glaucoma (OAG) who underwent a 360° suture trabeculotomy ab interno followed by ripasudil treatment beginning 1 month postoperatively. We compared 27 of these patients, by using propensity score analysis, with 27 patients in a matched control group who had no ripasudil treatment. We assessed the changes in the mean intraocular pressure (IOP) and the relationship between the IOP changes and background factors. All eyes had a complete 360° Schlemm’s canal incision and phacoemulsification. The mean IOP at 1 and 3 months after ripasudil administration were significantly reduced by −1.7 ± 1.9 mmHg (p < 0.0001) and −1.3 ± 2.3 mmHg (p = 0.0081) in the ripasudil group, respectively, but IOP in the control group was not significantly reduced. The IOP reduction was significantly associated with the IOP before ripasudil treatment (p < 0.001). In conclusion, the use of ripasudil for patients with OAG after circumferential incision of the Schlemm’s canal produced significant IOP reductions. Ripasudil may affect the distal outflow tract, thereby leading to the IOP reduction.


2021 ◽  
Vol 13 (2) ◽  
pp. 62-68
Author(s):  
Nisha Manandhar ◽  
Chandni Pradhan ◽  
Purushottam Joshi ◽  
Prabha Subedi ◽  
Pranav Shrestha

Introduction: Glaucoma is one of the major causes of irreversible blindness. In Nepal, the most common type of Glaucoma seen is Primary Open Angle Glaucoma. There are many risk factors associated with Primary Open Angle Glaucoma. The main objective of the study was to compare ocular biometric parameters in patients diagnosed with Primary Open Angle Glaucoma and age matched controls. Material and methods: This is a hospital based cross sectional study done at Mechi Eye Hospital. The study included 137 cases of Primary Open Angle Glaucoma and 75 normal individuals as control.  Axial length (AL), anterior chamber depth (ACD), Keratometry ‘K’ value and Central Corneal Thickness (CCT) were measured. Mann – Whitney U test was used for statistical analysis. Results: Mean age in Primary Open Angle Glaucoma group was (55.25 ± 10.16 years) and in the control group was (60.96 ± 10.91 years). Axial length  in the Primary Open Angle Glaucoma group (23.16 ±1.19 mm) was deeper as compared to the control group (22.69 ±0.89 mm), the difference was statistically significant (p<0.001). Anterior chamber depth (ACD) was statistically deeper in the Primary Open Angle Glaucoma group (3.05 ±0.51 mm) as compared to the control group (2.86 ±0.46 mm), (p<0.01). Central corneal thickness (CCT) was thinner in the Primary Open Angle Glaucoma group (519.5 ±36.25 um) as compared to the control group (525.40 ±37.77 um) but the difference was not found to be statistically significant (p<0.19). K value in Primary Open Angle Glaucoma (7.54 ±0.41mm) was higher than age-matched controls (7.58 ± 0.33mm) but the difference was not statistically significant (p<0.79). Conclusion: Patients with Primary Open Angle Glaucoma had longer Axial length (AL) and deeper Anterior chamber depth (ACD) as compared to normal individuals.


Author(s):  
Raji Mohammad Mehdi

Background: Primary Open-Angle Glaucoma (POAG) the most common form of glaucoma is a neurodegenerative disease, which is the third most common cause of blindness worldwide. It is estimated that 60 million people in the world are affected by this disease and 8.4 million are bilaterally blind. Among the various factors that have been implicated in the pathophysiology of this disease is infection with Helicobacter pylori (HP), a Gram-negative bacterium that is commonly found in stomach and present in approximately one-half of the world’s population. Establishment of such a causal correlation will probably have important practical applications as the eradication of H. pylori might lead to developments in the treatment of glaucoma. Objectives: To investigate the association between Primary Open-Angle Glaucoma (POAG) and Helicobacter Pylori infection and to observe fluctuations in intra ocular pressure after Helicobacter Pylori infection eradication. Design: Duration based, prospective observational study. Participants: 50 patients with documented Primary Open-Angle Glaucoma (POAG) as case group and 50 non-glaucoma participants as control group. Methods: Upper gastrointestinal endoscopy was performed to evaluate macroscopic abnormalities, and gastric mucosal biopsy specimens were obtained for the presence of H. pylori infection tested by Rapid Urease Test (RUT). All subjects underwent detailed ocular examinations including visual acuity, slit-lamp examination, fundoscopy, intra-ocular pressure recording, gonioscopy, GHT to assess visual fields and OCT of optic nerve head. Results: In 90% of POAG patients of case group and in 68% of non-glaucoma participants of control group Helicobacter pylori infection was detected by RUT (P-Value=0.007). Conclusion: H. pylori infection is more frequent in glaucoma patients, perhaps more so in those of Indian ethnicity. It may play a role as a secondary aggravating factor or even may be the primary cause. The establishment of such a causal relationship will probably have important practical applications as the eradication of H. pylori might lead to developments in the treatment of glaucoma.


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