Long-term myofibroblast persistence in the capsular bag contributes to the late spontaneous in-the-bag intraocular lens dislocation

Lens capsule pathological characteristics in cases of intraocular lens dislocation with atopic dermatitis

PURPOSE

To explore lens capsule pathological characteristics in intraocular lens (IOL) dislocation after cataract surgery in patients with atopic dermatitis (AD).

SETTING

University hospital department of ophthalmology.

DESIGN

Case series with clinicopathological correlations.

METHODS

Lens capsules and surrounding tissues excised during surgery from eyes with AD (AD group) and eyes without AD (non-AD group) with IOL dislocation were histologically evaluated. Hematoxylin and eosin staining was used to assess abnormal changes in lens epithelial cells (LECs). Masson trichrome staining distinguished the fibrous metaplasia around the lens capsule into high-density and low-density fibrosis. Capsular splitting (thinning) was identified in both stained preparations.

RESULTS

The IOL dislocation morphology in the AD group (10 eyes of 10 patients) included 7 cases of capsular bag dislocation (CBD) and 3 cases of dead bag syndrome (DBS), with an average duration to IOL dislocation of 11.5 ± 5.6 years. All patients in the non-AD group (12 eyes of 12 patients) had CBD, averaging 10.2 ± 5.7 years to dislocation. Abnormal LECs, low-density fibrosis, and capsular splitting were observed in 9 (90), 9 (90), and 6 (60) of the patients in the AD group compared with 6 (50), 3 (25), and 2 (18), respectively, in the non-AD group (total n [%]).

CONCLUSIONS

Compared with the non-AD group, the AD group exhibited higher frequencies of morphological changes in LECs, low-density fibrosis around the lens capsule, and capsular splitting characteristics of DBS. These results suggest LEC degeneration and increased lens capsule fragility occurred in patients with AD.

Exploring anterion capsular contraction syndrome in cataract surgery: insights into pathogenesis, clinical course, influencing factors, and intervention approaches

Anterior capsular contraction syndrome (ACCS) is a challenging complication that can occur following phacoemulsification cataract surgery. Characterized by capsular bag wrinkling, intraocular lens (IOL) decentration and tilt, ACCS can have negative effects on visual outcomes and patient satisfaction. This review aims to investigate the pathogenesis, clinical course, influencing factors, and intervention approaches for ACCS after cataract surgery. By understanding the underlying mechanisms and identifying factors that contribute to ACCS, surgeons can enhance their ability to predict and manage this complication. Various intervention strategies are discussed, highlighting their importance in reducing complications and improving surgical outcomes. However, further research is needed to determine optimal prevention and management strategies through long-term follow-up and comparative analyses. Advancements in this field will ultimately lead to improved visual outcomes and optimized cataract surgery for patients.

The Immediate Early Response of Lens Epithelial Cells to Lens Injury

Cataracts are treated by lens fiber cell removal followed by intraocular lens (IOL) implantation into the lens capsule. While effective, this procedure leaves behind numerous lens epithelial cells (LECs) which undergo a wound healing response that frequently leads to posterior capsular opacification (PCO). In order to elucidate the acute response of LECs to lens fiber cell removal which models cataract surgery (post cataract surgery, PCS), RNA-seq was conducted on LECs derived from wild type mice at 0 and 6 h PCS. This analysis found that LECs upregulate the expression of numerous proinflammatory cytokines and profibrotic regulators by 6 h PCS suggesting rapid priming of pathways leading to inflammation and fibrosis PCS. LECs also highly upregulate the expression of numerous immediate early transcription factors (IETFs) by 6 h PCS and immunolocalization found elevated levels of these proteins by 3 h PCS, and this was preceded by the phosphorylation of ERK1/2 in injured LECs. Egr1 and FosB were among the highest expressed of these factors and qRT-PCR revealed that they also upregulate in explanted mouse lens epithelia suggesting potential roles in the LEC injury response. Analysis of lenses lacking either Egr1 or FosB revealed that both genes may regulate a portion of the acute LEC injury response, although neither gene was essential for expression of either proinflammatory or fibrotic markers at later times PCS suggesting that IETFs may work in concert to mediate the LEC injury response following cataract surgery.

Predicting the biomechanical stability of IOLs inside the postcataract capsular bag with a finite element model

BACKGROUND AND OBJECTIVES

Although cataract surgery is a safe operation in developed countries, there is still room for improvement in terms of patient satisfaction. One of the key issues is assessing the biomechanical stability of the IOL within the capsular bag to avoid refractive errors that lead to a second surgery. For that purpose, a numerical model was developed to predict IOL position inside the capsular bag in the short- and long-term.

METHODS

A finite element model containing the implanted IOL, the postcataract capsular bag, the zonules, and a portion of the ciliary body was designed. The C-loop hydrophobic LUCIA IOL was used to validate the numerical model and two more worldwide IOL designs were tested: the double C-loop hydrophobic POD FT IOL and the plate hydrophilic AT LISA IOL. To analyze the biomechanical stability in the long-term, the effect of the fusion footprint, which occurs days following cataract surgery, was simulated. Moreover, several scenarios were analyzed: the size and location of the capsulorexhis, the capsular bag diameter, the initial geometry of the capsular bag, and the material properties of the bag.

RESULTS

The biomechanical stability of the LUCIA IOL was simulated and successfully compared with the in vitro results. The plate AT LISA design deformed the capsular bag diameter up to 11.0 mm against 10.5 mm for the other designs. This design presented higher axial displacement and lower rotation, 0.19 mm and 0.2^∘, than the C-loop design, 0.09 mm and 0.9^∘.

CONCLUSIONS

All optomechanical biomarkers were optimal, assuring good optical performance of the three IOLs under investigation. Our findings showed that the capsulorexhis size influences the stiffness of the capsular bag; however, the shape in the anterior and posterior curvature surfaces of the bag barely affect. The results also suggested that the IOL is prone to mechanical perturbations with the fusion footprint, but they were not high enough to produce a significant refractive error. The proposed model could be a breakthrough in the selection of haptic design according to patient criteria.

Knockdown of LncRNA NEAT1 inhibits myofibroblast activity in oral submucous fibrosis through miR-760/TPM1 axis

Background/purpose

Oral submucous fibrosis (OSF) is a fibrotic disease with high transformation of malignant disorders. Aberrant expression of lncRNA nuclear enriched abundant transcript 1 (NEAT1) was engaged with various fibrosis models, but its mechanism in OSF remained elusive.

Materials and methods

Fibrous buccal mucosa fibroblasts (fBMFs) were from OSF specimens. Myofibroblast activities including the alpha smooth muscle actin (α-SMA) distribution and invasion capacities were determined by Immunocytochemistry and Transwell assays. Gene and protein were identified by quantitative real time polymerase chain reaction or western blotting. Binding relationship was analyzed via Starbase and dual-luciferase reporter or RNA immunoprecipitation assays.

Results

NEAT1 and Tropomyosin-1 (TPM1) were significantly increased in OSF specimens, but miR-760 was decreased. NEAT1 knockdown repressed myofibroblast activities and reduced the fibrosis and Wnt/β-catenin pathway via miR-760/TPM1 axis. MiR-760 inhibition could reverse the regulation of NEAT1 knockdown via TPM1 in fBMFs.

Conclusion

NEAT1 knockdown inhibited myofibroblast activities and Wnt/β-catenin pathway via miR-760/TPM1 axis in fBMFs. NEAT1 could be the target for inhibiting myofibroblast activities in fBMFs for OSF treatment.

Inhibition of suppressor of cytokine signaling-3 affects mesangial cell proliferation and cell cycle in mesangioproliferative glomerulonephritis

To explore the role of suppressor of cytokine signaling-3 (SOCS-3) in mesangial proliferative glomerulonephritis (MsPGN). SOCS-3 expression in kidney tissues from MsPGN patients was detected using immunohistochemistry. Double immunofluorescence staining was performed to investigate the localization of SOCS-3 with α-SMA in glomeruli. Heminephrectomized wild-type (WT) and SOCS-3^-/- (KO) mice were injected with Habu-snake venom (HSV) to establish MsPGN models, and renal function were compared. Simultaneously, immunofluorescence, periodic acid-Schiff staining, Picrosirius red staining, as well as immunohistochemistry for PCNA, MAC-2 and type IV collagen in glomeruli were performed. In addition, primary mouse renal mesangial cells and SV40 MES-13 cells were transfected with SOCS-3 siRNA or SOCS-3 lentiviral activation particles, followed by EdU assay, flow cytometry, quantitative reverse transcription-polymerase chain reaction, and Western blotting. Mesangial SOCS-3 expression was enhanced in glomeruli of MsPGN patients, and SOCS-3 was well co-localized with activated α-SMA. After HSV injection, WT and KO mice presented with the increases in the serum creatinine, urea nitrogen, and urinary protein, especially in KO mice. Besides, SOCS-3^-/- alleviated the hyperplasia of glomerular MCs in MsPGN mice, with the reductions in PCNA, MAC-2, and collagen deposition. Furthermore, SOCS-3 inhibition reduced the cell proportion at S phase to suppress cell proliferation, with the downregulations of Cyclin A, Cyclin D1, PCNA, and Ki-67. SOCS-3 knockout can alleviate the hyperplasia of glomerular MCs in MsPGN mice via affecting the cell cycle and proliferation of MCs, thus being a potential therapeutic target for MsPGN.

The effect of sex on the mouse lens transcriptome

The transcriptome of mammalian tissues differs between males and females, and these differences can change across the lifespan, likely regulating known sexual dimorphisms in disease prevalence and severity. Cataract, the most prevalent disease of the ocular lens, occurs at similar rates in young individuals, but its incidence is elevated in older women compared to men of the same age. However, the influence of sex on the lens transcriptome was unknown. RNAseq based transcriptomic profiling of young adult C57BL/6J mouse lens epithelial and fiber cells revealed that few genes are differentially expressed between the sexes. In contrast, lens cells from aged (24 month old) male and female C57BL/6J mice differentially expressed many genes, including several whose expression is lens preferred. Like cataracts, posterior capsular opacification (PCO), a major sequela of cataract surgery, may also be more prevalent in women. Lens epithelial cells isolated from mouse eyes 24 h after lens fiber cell removal exhibited numerous transcriptomic differences between the sexes, including genes implicated in complement cascades and extracellular matrix regulation, and these differences are much more pronounced in aged mice than in young mice. These results provide an unbiased basis for future studies on how sex affects the lens response to aging, cataract development, and cataract surgery.