Diabetic Cataract In Rats Research Articles

Potential prophylactic effect of Naringenin loaded liposome eye drops on streptozotocin-induced diabetic cataract in rats

Potential prophylactic effect of Naringenin loaded liposome eye drops on streptozotocin-induced diabetic cataract in rats

Efficacy of N-Acetylcysteine (NAC) Against Malondialdehyde (MDA) Levels in Diabetic Cataracts: In vivo Study

Background: Diabetes mellitus is a systemic condition that affects various organs, including the eyes. N-acetylcysteine ​​(NAC) functions as an antioxidant because it belongs to a thiol group synthesis glutathione. However, the availability of cysteine ​​in the body is only 15%, so cysteine ​​supplementation can help with oxidative stress in diabetic cataracts. That it will prevent the reaction of lipid peroxidase and the formation of PUFA in the lens membrane, which causes damage to lens cells and is characterized by an increase in malondialdehyde. This study aims to determine the comparison of malondialdehyde levels in the lenses of diabetic cataract rats given or without topical NAC.
 Methods: 36 rats were divided into the control group (received streptozotocin) and treatment group (received streptozotocin and topical NAC. Intraperitoneal injection of streptozotocin was given 90 mg/kg BW and performed once a week for 3 weeks. GDP examination was performed the next day after the rats fasted for 16 hours from the vein. In the tail, GDP > 110 mg/dl categorized as diabetes. Topical NAC was given 4 times per day for 3 weeks. At the end of the study, the lens was extracted for the measurement of malondialdehyde.
 Results: The mean MDA levels in the control group were higher (2.90±0.71nmol/ml) than in the treatment group (2.33±0.38nmol/ml), p<0.05.
 Conclusion: NAC was effective in reducing oxidative stress levels in diabetic cataract lenses by lowering MDA levels better than the group that did not receive MDA in vivo.

Simultaneous amelioration of diabetic ocular complications in lens and retinal tissues using a non-invasive drug delivery system

Topically administered delivery systems for ophthalmic applications have been studied for the treatment of anterior or posterior eye diseases. However, simultaneous treatment of both anterior and posterior eye diseases has not been explored. In this study, we fabricated a topically administrable polymeric nanoparticle (NP)- based delivery system consisting of pluronic®F-68 shell and polycaprolactone core for the simultaneous treatment of both anterior and posterior eye diseases. These NPs were loaded with pyrrolidine dithiocarbamate (PDTC) or triamcinolone acetonide (TA) separately. The drug loading in NPs was optimized to initially achieve a moderate burst release of PDTC followed by slow and sustained release of both PDTC and TA. The resultant delivery system was studied for its in vivo efficacy in a diabetic retinopathy (DR) and cataract rat model. The results demonstrated that administration of PDTC NPs + TA NPs minimized oxidative stress in lens as evidenced by reduced levels of protein carbonyls and malondialdehyde, and, ameliorated DR complications in retina as evidenced by reduced expression of hypoxia inducible factor-1α along with a reduction in number of neovascular tufts and acellular capillaries. Therefore, delivery of PDTC and TA using PCL-PF68 NPs could be a useful approach for simultaneous treatment of diabetic cataract and DR.

Study on Inhibitory Effect of Salidroside on Diabetic Cataract in Rats

Study on Inhibitory Effect of Salidroside on Diabetic Cataract in Rats

Effects of Dendrobium candidum polysaccharides on microRNA-125b and mitogen-activated protein kinase signaling pathways in diabetic cataract rats

Effects of Dendrobium candidum polysaccharides on microRNA-125b and mitogen-activated protein kinase signaling pathways in diabetic cataract rats

Topical nerve growth factor attenuates streptozotocin-induced diabetic cataracts via polyol pathway inhibition and Na+/K+-ATPase upregulation

The purpose of this study was to investigate whether and how topical nerve growth factor (NGF) attenuates streptozotocin (STZ)-induced diabetic cataracts in vivo. Rats were randomly divided into three groups, including the normal control rat group, STZ-induced diabetic cataract rat group (DM group), and STZ-induced diabetic cataract rat group treated with 200 μg/mL recombinant rat β-NGF (DM + NGF group). Cataract formation was evaluated by portable slit lamp biomicroscopy following pupil dilation at 8 weeks. The expression levels of NGF, aldose reductase (AR), and Na+/K+-ATPase in the lens epithelial cells (LECs) of the three groups were measured in the presence or absence of topical NGF. TUNEL-positive LECs were quantified to determine if hyperglycemia caused LEC apoptosis. At 8 weeks, the mean cataract score in the control group was significantly lower than that in DM and DM + NGF groups, and the score in the DM + NGF group was significantly lower than that in the DM group. At the equatorial zone and anterior central zone of lens, NGF and Na+/K+-ATPase expression levels were significantly decreased in the DM group; however, they were partially restored in the DM + NGF group. At the equatorial zone and anterior central zone of lens, AR expression and TUNEL-positive apoptotic LECs were significantly increased in the DM group compared with the control group, however, they were significantly decreased in the DM + NGF group. In conclusion, topical NGF could delay the progression of diabetic cataracts by attenuating polyol pathway activation and increasing Na+/K+-ATPase protein levels.

Identification of tRNA-derived fragments and their potential roles in diabetic cataract rats.

Aim: To illustrate the expression profile of transfer RNA-derived fragments and reveal their putative role in the pathogenesis of diabetic cataract (DC) rats. Materials & methods: Small RNA sequencing was conducted in the lens epithelium of rats lens. The data were validated by quantitative real-time PCR, and bioinformatic analysis was performed to explore the roles of the fragments in DC pathogenesis. Results: A total of 213 differentially expressed tRNA-related fragments were identified, in which 111 were upregulated and 102 were downregulated in DC rats. Bioinformatics analysis revealed that several associated pathways might participate in the development of DC rats. Conclusion: tRNA-derived fragments may be involved in the pathogenesis of DC rats.

Antioxidant and anti-glycated TAT-modified platinum nanoclusters as eye drops for non-invasive and painless relief of diabetic cataract in rats

Diabetic cataract (DC) is a kind of worrying ocular complications that eventually leads to blindness. However, there are a narrow range of pharmacological interventions to enable control the progression of DC, especially the eye drops based on noninvasive routes. In this work, we developed a kind of strong antioxidant Pt nanoclusters coated with cell-penetrating peptide (TAT) conjugated dextran (DTPNCs). The DTPNCs were dispersed in 0.1% Pluronic F127 (W/V) to form eye drops, which have the ability of corneal permeation. The results indicate that the presence of 0.1% Pluronic F127 (W/V) resists the clearance of tear film against DTPNCs and TAT-conjugated dextran contribute to the interaction and permeation with corneal barriers with the help of electrostatic interaction in vivo. More importantly, the DTPNCs possess effective antioxidant capacities and can protect the lens epithelial cells against oxidative stress by eliminating ROS and impose restrictions on the α-crystallin glycation and crosslinking in vitro, further to slow down the process of DC. We hope that our approach will provide a promising non-invasive and painless treatment to DC.

Puerarin prevents cataract development and progression in diabetic rats through Nrf2/HO‑1 signaling.

Puerarin is the major bioactive ingredient isolated from the dry root of Pueraria lobata, a plant used in traditional Chinese medicine. Puerarin has been used to treat diabetes and cataracts in China; however, its underlying mechanism of action remains unclear. The aim of the present study was to investigate the effectiveness and mechanism of puerarin in preventing cataracts in diabetic rats. Diabetes was induced by streptozocin (STZ) administration and rats were intraperitoneally injected with puerarin (25, 50 and 100 mg/kg). Blood glucose levels and cataract development were examined in the different experimental groups. In addition, the expression levels of markers associated with oxidative stress, including nuclear factor erythroid 2 like 2 (Nrf2) and heme oxygenase-1 (HO-1), were analyzed. The present results suggested that treatment with puerarin at 25, 50 and 100 mg/kg significantly reduced blood glucose levels and the incidence of cataract in STZ-induced diabetic rats. Additionally, puerarin treatment reduced oxidative stress, restoring the levels of malondialdehyde and glutathione, and the activity of glutathione peroxidase. Furthermore, puerarin administration decreased the expression levels of retinal vascular endothelial growth factor and interleukin-1β and increased the mRNA expression levels of Nrf2 and HO-1, thus inhibiting oxidative stress. The present findings suggested that puerarin had hypoglycemic effects and that it prevented cataract development and progression in diabetic rats by reducing oxidative stress through the Nrf2/HO-1 signaling pathway.

Potential prophylactic effect of chemical chaperones for alleviation of endoplasmic reticulum stress in experimental diabetic cataract

BackgroundImbalance between protein synthesis and endoplasmic reticulum (ER) capacity to modify and fold proteins lead to the accumulation of unfolded proteins resulting in ER stress and apoptosis. Chaperones are major defense molecules assisting in protein folding, transport, and cellular signaling. ER stress plays a major role in the pathogenesis of diabetes mellitus (DM) and its complications, e.g., diabetic cataract. In the present investigation, the chemical chaperones 4-phenylbutyric acid (4-PBA), tauroursodeoxycholic acid (TUDCA), and trimethylamine N-oxide (TMAO) are used as potential therapeutic agents for alleviation of DM-induced ER stress and diabetic cataract in rats. Animals are subjected to biochemical analysis of blood and lenses for ER stress and apoptosis markers. Moreover, ophthalmologic examination and histopathologic examination of the lenses were done to confirm the results.ResultsBoth ophthalmic and lens histopathologic examination revealed that treatment with 4-PBA and TUDCA retarded the occurrence of cataract markedly. Whereas, treatment with TMAO caused a partial improvement of cataract. Moreover, biochemical tests showed that both 4-PBA and TUDCA produced a remarkable improvement in the ER marker levels (VEGF and caspase-12), GSH, MDA, TAC levels in lens tissues. On the other hand, TMAO had no significant effect on these parameters. However, Western blot analysis of lens homogenates showed a suppressed expression of GRP78 and CHOP after treatment with 4-PBA, TUDCA, and TMAO. Moreover, all treated groups showed a significant improvement of lens soluble proteins and their UV spectra absorption. A significant improvement in fasting blood sugar, GSH, serum MDA, and TAC were noted in all treated groups. 4-PBA produced a significant decrease in insulin resistance, whereas TUDCA and TMAO showed insignificant change.ConclusionThe present research found that the tested chaperones could be used as a therapeutic approach for clinically relevant disorders featuring ER dysfunction such as DM and for reducing its complications in the eye mainly cataract. However, TUDCA and 4-PBA were found to have a more potential efficacy in reducing most of the tested parameters as compared to TMAO.

Investigation of expression and effects of TGF-β1 and MMP-9 in lens epithelial cells of diabetic cataract rats.

Expressions and effects of transforming growth factor- 1 (TGF-β1) and matrix metalloproteinase-9 (MMP-9) in lens epithelial cells (LECs) of diabetic cataract rats were investigated. A total of 40 female Sprague-Dawley rats were randomly divided into study and control group. Rats in study group were successfully modeled diabetic cataract rats, and rats in control group were normal rats. Immunohistochemical staining was used to determine positive and negative granules in cytoplasm, and image proplus image analysis system to calculate the integral optical density of the average positive area. Quantitative analysis was performed on TGF-β1 and MMP-9 in LECs of rats in study and control groups at the 2nd and 4th weekends. There were no statistically significant differences in length and age between the two groups of rats (P>0.05). Glucose concentration in the blood of rats in study group after modeling was significantly higher than that before modeling (P<0.001), and that after modeling was significantly higher in study group than that in control group (P<0.001). The expression of TGF-β1 protein in LECs of rats in study group at T2 (the 4th weekend) was significantly higher than that at T1 (the 2nd weekend) (P<0.001), and that of TGF-β1 protein was significantly higher in study group than that in control group at T1 and T2 (P<0.001). The expression of MMP-9 protein in LECs of rats in study group at T2 was significantly higher than that at T1 (P<0.001), and that of MMP-9 protein was significantly higher in study group than that in control group at T1 and T2 (P<0.001). The TGF-β1 expression was positively correlated with the MMP-9 expression in LECs of diabetic cataract rats (r=0.825, P<001). The increased expression of MMP-9 and TGF-β1 may play an important role in the occurrence and development of diabetic cataract.

Prevention of α-crystallin glycation and aggregation using l-lysine results in the inhibition of in vitro catalase heat-induced-aggregation and suppression of cataract formation in the diabetic rat.

The principle role of α-crystallin is chaperoning activity that protect s other proteins against different stresses. High glucose concentration induces the osmotic stress and results in biomacromolecules glycation, which is subsequently cause their conformational and functional changes. Here, the roles of l-lysine (Lys) on the prevention of α-crystallin glycation in both in vitro and in vivo conditions are investigated. The catalase (CAT) activity was considered as a marker of α-crystallin functionality in both conditions. Streptozotocin-induced diabetic rats were treated with 0.1% of the Lys in drinking water. The purified α-crystallin was also incubated with glucose, in the presence or absence of the Lys and its structure-function was compared. The results showed that the visual cataract score was significantly lower in the diabetic rats treated with Lys. After Lys treatment, CAT, superoxide dismutase, aldose reductase and other biochemical parameters in the lens and serum of the diabetic rats returned to the normal value. Formation of the advanced glycation endproducts (AGEs), protein cross-linking, and the hydrophobicity of α-crystallin were changed due to glycation, but they were reversed by Lys treatment. The glycated α-crystallin lost its chaperone activity against heat denatured-CAT, but in the presence of Lys, it preserved its activity and prevented CAT aggregation. In conclusion, Lys treatment significantly inhibited the progression of diabetic cataract in rats. These effects were due to the Lys antiglycating and antioxidant effects, in addition to its protective effect against α-crystallin chaperoning activity.

Delaying Effect of Polyherbal Formulation on Cataract in STZ-NIC-induced Diabetic Wistar Rats

The aim of the study was to evaluate the effectiveness of polyherbal formulation on cataract development in streptozotocin-nicotinamide-induced diabetic rats. Diabetes was induced by streptozotocin (65 mg/kg, ip) and nicotinamide (90 mg/kg, ip). The diabetic rats were orally treated with polyherbal formulation (therapeutic dose, 28.71 mg/kg and 2×therapeutic dose, 57.42 mg/kg) and metformin (150 mg/kg), for 12 weeks. Serum glucose levels, body weight, histopathology of pancreas were used to evaluate the antidiabetic activity while the histopathological study of eye and protein content in lens were used to evaluate the protective effect of polyherbal formulation on cataract development. The progression of cataract in rat lens was observed with a slit-lamp biomicroscope. A daily treatment of polyherbal formulation for 12 weeks resulted in significant (p<0.05) decrease in serum glucose level, body weight and improved protein content in the lens. It also delayed the incidence of cataract in diabetic rats. The histopathological study showed that there was regeneration of pancreatic β-cells. The results observed with polyherbal formulation were found to be comparable to those obtained with metformin. Results suggested that the polyherbal formulation possessed antidiabetic activity and prevented cataract development.

Evaluation of the effect of Nishamalaki on cataract in diabetic rats

Background: Diabetes mellitus is a metabolic disorder, leading to many complications. Cataract is important complication causing impairment of vision. Many factors play a role in cataract formation in diabetic individuals. Only treatment for cataract is surgery, having limitations. There is a need to explore for inexpensive, non-surgical approaches for prevention of cataract. The present study was planned to evaluate the effect of Nishamalaki (NA) on diabetic cataract. Aims and Objectives: This study aims to study the prophylactic and therapeutic effect of NA on cataract and its mechanism of action. Materials and Methods: Diabetes was induced in 42 Wistar rats with low-dose streptozotocin (STZ) followed by high-fat high-fructose diet. NA treatment initiated in six rats immediately after STZ administration (NA prophylactic Group II). Once diabetes was developed rats divided into six groups and received respective treatment for 8 weeks: Group I – diabetic control, Group III – NA therapeutic, Group IV – glimepiride, Group V – chloramphenicol, Group VI – glutamine, and Group VII – epalrestat. Then, estimation of aldose reductase (AR) and antioxidant enzymes in blood and lens was done. Results: In Group I, cataract was initiated in the 2nd week and progressed to Stage 3 or 4 by the 8th week. No cataract was developed in NA prophylactic and chloramphenicol group. Delayed initiation and progression were seen in NA therapeutic and epalrestat, compared to glimepiride and glutamine group. NA was seen to work by antihyperglycemic, antioxidant, AR inhibition, and probably by CYP 450 inhibition. Conclusion: NA is useful in the prevention and treatment of cataract in diabetic animals, working through many mechanisms.

Ursodeoxycholic acid suppresses the formation of fructose/streptozotocin-induced diabetic cataract in rats.

The main objective of this study was to investigate the potential protective effect of ursodeoxycholic acid (UDCA) on fructose/streptozotocin-induced diabetic cataract in rats. The diabetic model (DM) was induced through the administration of 10% fructose in drinking water for 2 weeks followed by streptozotocin injection (intraperitoneal). One week later, hyperglycemia was assisted and diabetic animals were treated with UDCA either as local eye drops (0.5% solution, four times/day) or orally (100 mg/kg b.w.). Cataract formation was monitored biweekly and scored into four stages. After 12 weeks of treatment, rats were subjected to ophthalmological examination, and then, their blood and lenses were prepared for biochemical analysis of glucose, insulin, reduced glutathione, total antioxidant capacity, malondialdehyde, hydrogen peroxide, caspase-12, and lenticular total proteins. In addition, tertiary structure and conformational changes of lenticular soluble proteins were analyzed using SDS-PAGE and UV absorption while changes in lenticular α-crystallin structure were investigated using intrinsic tryptophan fluorescence. Results demonstrated that both local and oral UDCA restored the normal levels of lens T-AOC, MDA, H2 O2 , and caspase-12 and improved noticeably the levels of the lens GSH and total proteins. In addition, conformational and tertiary structure changes of soluble lens proteins were significantly reduced in UDCA-treated groups. Morphological examination of lenses revealed decreased score of cataract progression in UDCA-treated groups compared to DM animals. It was concluded that UDCA decreased the incidence of diabetic cataract by maintaining the antioxidant status, reducing the endoplasmic reticulum stress, and suppressing the structural changes of soluble lens proteins.

Antidiabetic cataract effects of GbE, rutin and quercetin are mediated by the inhibition of oxidative stress and polyol pathway.

One of the earliest critical secondary complications of diabetes is the opacification of the eye lens - a condition strictly associated with diabetic cataract. The study presented here was designed to investigate the effect of Ginkgo biloba extract (GbE), rutin and quercetin on streptozotocin (STZ) induced diabetic cataract (DC) rats. Ten weeks after administration of GbE, rutin and quercetin, the opacity of diabetic rats' lenses was graded under a slit lamp. Then, the levels of malondialdehyde (MDA), reduced glutathione (GSH), advanced glycosylation end products (AGEs), and the activities of aldose reductase (AR) were estimated. The DC-induced rats produced less GSH, higher levels of MDA and AGEs as well as elevated AR activity when compared to the normal group. Administration of GbE, rutin and quercetin remarkably inhibited the AR activity, stimulated the production of glutathione, and decreased the levels of MDA and AGEs in the lenses of DC-induced rats, which eventually delayed the progression of lens opacification in diabetic rats to various degrees. Our results revealed that quercetin had the highest significant (P<0.05) potential to delay the progression of STZ-induced diabetic cataract when compared with rutin and GbE. The mechanism dictating this interesting prowess of quercetin might be attributed to its AR inhibitory strength, anti-lipid peroxidation potential and anti-AGEs activity.

Effects of calcium dobesilate on Nrf2, Keap1 and HO-1 in the lenses of D-galactose-induced cataracts in rats.

This study investigated the effects of calcium dobesilate on Nrf2, Keap1 and HO-1 in the lenses of D-galactose-induced cataracts in rats. Thirty Sprague-Dawley rats were randomly divided into three groups: a blank control group, a model control group and a model administration group. A normal diet was given to the rats in the blank control group and the rats with D-galactose-induced cataracts of the model control group. Calcium dobesilate was also given to the rats with D-galactose-induced cataracts of the model administration group. A slit lamp microscope was used to check the degree of lens opacity. RT-PCR and western blot analysis were used to detect the mRNA and protein expression of Nrf2, Keap1 and HO-1 in the lenses of the three groups. There was a significant difference in the degree of lens opacity among the three groups (P<0.05). The model control group was the most turbid of the three groups, followed by the model administration group. Moreover, the mRNA and protein expression of Nrf2, Keap1 and HO-1 in the lenses of the three groups were also significantly different (P<0.05). The mRNA levels of Nrf2 and HO-1 were the highest in the model control group, followed by the model administration group, and were the lowest in the blank control group. However, the mRNA expression level of Keap1 among the three groups had an opposite trend. In conclusion, calcium dobesilate can effectively increase the levels of Nrf2 and HO-1 in the lenses of diabetic cataract rats and inhibit the level of Keap1. Therefore, the therapeutic effect of calcium dobesilate against cataracts is related to the improvement of the Nrf2-Keap1 signaling pathway.

Potential of CeCl3@mSiO2 nanoparticles in alleviating diabetic cataract development and progression

Cataract is a major cause of visual impairment for diabetic patients. It is imperative to develop efficient therapeutic agents against diabetic cataract (DC) because diabetes confers higher risk for complications after cataract surgery. We have previously reported the role of CeCl3 loaded mesoporous silica (CeCl3@mSiO2) nanoparticles in reducing the oxidative stress of lens epithelial cells. However, the potential of CeCl3@mSiO2 in preventing diabetic cataract development remains unclear. In this study, we applied CeCl3@mSiO2 nanoparticles with a size of 87.6±8.9nm to streptozotocin-induced diabetic cataract rat model by intraperitoneal injection. Our results showed that CeCl3@mSiO2 efficiently ameliorated the progression of DC. Consistent with antioxidant effect of CeCl3@mSiO2in vitro, administration of CeCl3@mSiO2 significantly abrogated hyperglycemia-mediated upregulation of advanced glycation end products, lipid peroxidation and protein carbonylation in animal lens. Taken together, our study provides a potential nanodrug to manage the development of DC.

Protective effect of Tephrosia purpurea in diabetic cataract through aldose reductase inhibitory activity.

Tephrosia purpurea (T. purpurea) has been reported to prevent cataract formation in senile cataract model as well as proven effective in STZ induced type 1 diabetes. Aldose reductase (AR) is a key enzyme in the intracellular polyol pathway responsible for the development of diabetic cataract. To investigate the effects of T. purpurea in the light of inhibition of aldose reductase enzyme in polyol pathway. We studied the effects of alcoholic extract and flavonoid fraction of T. purpurea in streptozotocin (STZ, 45mg/kg, i.v.)-induced type I diabetic cataract in rats. The animals were divided into five groups as control, control treated with alcoholic and flavonoid fraction, diabetic control and diabetic treated with alcoholic and flavonoid fraction. In-vitro aldose reductase inhibitory activity was also evaluated. Further, molecular docking study was performed with crystal structure of aldose reductase and its known chemical constituents of the plant. The IC50 value of alcoholic extract for aldose reductase inhibition was found to be 209.13μg/ml, and that of flavonoid fraction was found to be 46.73μg/ml. Administration of STZ produced significantly abnormal levels of serum glucose, serum insulin, soluble protein and antioxidants in the lens homogenate. Treatment with alcoholic extract and flavonoid fraction of T. purpurea were able to normalize these levels. Some of the active constituents of T. purpurea showed significant interactions with aldose reductase enzyme in molecular docking studies. Our data suggested that both the extracts might be helpful in delaying the development of diabetic cataract due to the presence of rutin and quercetin. This beneficial effect may be due to its significant inhibition of aldose reductase enzyme and anti-oxidant activity.

The significance and expressions of MMP-3, Fn and α-SMA in lens epithelium cells of the experimental diabetic cataract rats

Objective To investigate pathological changes of lens epithelium cells (LECs) and expressions of matrix metalloproteinase-3 (MMP-3), alpha-smooth muscle actin (α-SMA), and fibronectin (Fn) in lens epithelial cells of experimental diabetic cataract rats, and to evaluate the roles of MMP-3, α-SMA, and Fn in the pathogenesis of diabetic cataract. Methods A total of 105 healthy Sprague-Dawley (SD) rats without lens diseases was randomly divided into normal control (n=45) and diabetic model (n=60) groups. Diabetic model rats were subjected to intraperitoneal injection of streptozotocin (STZ) (60 mg/kg), and those in the normal control group received injection with 0.1 mmol/L citric acid buffer solution of the same volume. The diabetic models were affirmed upon a fasting blood ≥16.65 mmol/L at the 3rd days after the injection. Once a week, the changes of blood glucose and body weight were monitored and the progression of cataract formation in both lenses of all rats was recorded with slit lamp observation. At end of 4 weeks, 8 weeks, and 12 weeks after STZ injection, lenses were isolated and embedded in paraffin. The LECs histopathology was examined with HE staining. Immunohistochemical method was used to detect expressions of MMP-3, α-SMA, and Fn in normal and diabetic LECs. The related comparisons and statistic analysis were carried out. Results The lenses of control group were always completely transparent throughout the period of experiment with 31.48%, 77.78%, and 100% of lenses in diabetic model group swelling at 4th, 8th, and 12th week, respectively. Under the light microscopic level, it has been showed that lens epithelium cells, which was occurred aggregate plaque and arranged in many layers, presented some morphologic characteristics of fibroblasts by HE staining. In control group LECs regularly, MMP-3, α-SMA, and Fn did not express equally; MMP-3, α-SMA, and Fn expressions increased obviously highly, difference had statistical significance compared to diabetic cataract group LECs (P<0.01). With the development of course of disease, the differences in expression of MMP-3, α-SMA, and Fn were significant between the diabetic cataract LECs and the control group (P<0.01). During the progression of diabetic cataract, the expression of Fn was positively correlated with that of α-SMA and MMP-3 (r=0.994, P<0.01; r=0.993, P<0.01). Conclusions The diabetic cataract living body animal model was established successfully, which has laid down necessary basis to expound the morbidity mechanism of diabetic cataract. In the lens of diabetic cataract group, the expressions of α-SMA, MMP-3, and Fn were significantly increased. They participated in the occurrence and development of diabetic cataract. The expression of Fn was positively correlated with α-SMA and MMP-3. The lens epithelium cells which took on elongated aspect like fibroblast cells appeared epithelial-mesenchymal transformation (EMT), which mediated the occurrence and development of LECs fibrosis. Key words: Cataract/CO/ME; Diabetes complications/ME; Lens, crystalline/CY/PA; Epithelial cells/PA; Matrix metalloproteinase 3/ME; Actins/ME; Fibronectins/ME