Development Of Senile Cataract Research Articles

Study of Serum Sodium and Potassium Levels in Senile Cataract Patients Versus Normal Controls at Tertiary Center

Aims: Senile cataract is a common eye condition that affects many older people and can lead to blindness if not treated. It is caused by the gradual thickening of the lens of the eye, which reduces the clarity of vision. One of the factors that may contribute to the development of senile cataract is the imbalance of serum electrolytes, which are minerals that help regulate the fluid balance in the body.
 Study Design: Hospital based prospective cross-sectional study.
 Methodology: The aim of this study was to compare the levels of serum sodium and potassium in senile cataract patients and healthy controls. The study involved 200 participants aged 50 to 80 years, 100 of whom had senile cataract and 100 of whom did not. The levels of serum electrolytes were measured using standard laboratory methods.
 Results: Senile cataract patients had significantly higher levels of serum sodium and potassium than healthy controls, while there was no significant difference in serum potassium levels between the two groups.
 Conclusion: The high levels of serum sodium and potassium may affect the concentration of these electrolytes in the aqueous humor, which is the fluid that fills the eye. This may overwhelm the ability of the lens to regulate its volume and lead to lens opacities. Therefore, serum sodium and potassium levels may be useful indicators of senile cataract risk. The study also suggested that reducing salt intake may help prevent or delay the onset of senile cataract.

Features of accumulation of chemical elements in the volume of the lens in senile cataract

This study provides a detailed analysis of the bioinorganic chemical composition of lens substance in patients with senile cataract using classical and spatial statistics methods. The study included 30 isolated human lenses. The light scattering ability (LSA) of the lens substance was evaluated using an original method. Additionally, distribution of chemical elements in the lens substance was analyzed using a scanning electron microscope with energy dispersive spectrometer (SEM/EDS). Measurements by all methods were carried out in a single coordinate space, which made it possible to compare the spatial correlation of different parameters. Small-angle light scattering of the lens substance has been quantitatively characterized for the first time. In contrast to the conventional norm, in senile cataract the accumulation fields of the majority of ion-forming elements (including Na, P, K, Cl) are distributed along the lines repeating the geometry of the lens capsule. At the same time, the light scattering ability of certain areas of the lens is significantly correlated with changes in the concentrations of Na, P, K, Ca in these areas. In particular, one ion-forming element can be distinguished - Na: spatial change of its concentration in senile cataract is strongly associated with a local change in LSA of the lens with opacities clustering of any degree. Thus, a change in the nature of the Na accumulation in the lens volume can be considered the main marker of senile cataract formation. The distribution pattern of ion-forming elements indicates that the loss of barrier properties in the capsule plays a significant role in the development of senile cataract.

РАЗРАБОТКА РИСК-ОРИЕНТИРОВАННОГО ПОДХОДА В ПРОФИЛАКТИКЕ СТАРЧЕСКОЙ КАТАРАКТЫ НА ОСНОВЕ КОМОРБИДНОЙ ПАТОЛОГИИ

Significance. Cataracts are the second most common cause of low vision and blindness. In this regard, development of a new analytical approach is required to optimize algorithms of preventive measures. The purpose of the study is to develop a method of screening diagnostics of age-related cataract among people aged 40-99, based on comorbid pathology, as well as an algorithm for stratification into target groups depending of the risk for senile cataract development. Material and methods. The study is based on information extracted from electronic medical records (EMRs) of patients aged 40-99 residing in Tambov and assigned to the city polyclinic (n=38328). The technique was developed using a binary logistic regression analysis with a step-by-step algorithm for including variables, where age-related cataract acted as the dependent variable, and age-related cataract risk factors associated with chronic diseases were used as independent variables. The models were compared by building ROC curves with calculations of the area under the curve (AUC). Results. A screening technique has been developed to identify individuals at high risk for developing age-related cataract among people aged 40 -99 based on data on chronic diseases associated with age-related cataract, including hypertension, coronary heart disease, cerebrovascular diseases, varicose veins of the lower extremities, and diabetes mellitus, taking into account age standardization. Data on the level of risk for developing age-related cataract made it possible to develop an algorithm for stratifying population into target groups, depending on the required level of sensitivity and specificity. Conclusion. Based on the data on cardiometabolic diseases associated with age-related cataract, a methodology was developed that allows to establish the risk level for developing age-related cataract among people aged 40-99, and an algorithm for stratification into target groups. Scope of application. The acquired knowledge can be used in the process of developing differentiated measures of primary prevention of age-related cataract, taking into account target groups and the established modifiable risk factors.

Risk Factors Which Lead to Development of Senile Cataract: A Review

Maturing processes, including those brought about by various outside factors, have stood out for researchers throughout the last years. Senile cataract is a multifactorial illness. The expense of surgery of cataract medical procedures stays among the highest costing procedures in general public healthcare. Age is an essential element that causes senile cataract morbidity, which double ten every ten years. This article considers some sources which portray research results on impact on cataract development by risk factors like age, sex, race, smoking, alcohol consumption, diabetes (pancreatic), usage of specific drugs, various environmental aspects, including ultraviolet and ionizing radiation; many of which are shown to cause increment or decrease the risk of senile cataract; there is clashing information on specific factors. Depending on etiology, experts spot senile, congenital, traumatic, complicated, and occupational cataracts. Senile cataract (hereafter referred to as “cataract”) is the most prevalent. The layout also contains quantitative data of cataracts and risk, given through odds ratio and advance because of age, alcohol consumption, ionizing radiation, etc. The researchers also express that there is still no finding on whether the dose-effect relationship for cataract evolvement is a non-threshold or threshold. Surgical procedures are the only treatment available. The surgical procedure usually needs less than an hour. The surgeon makes a small incision in the sclera or limbus of the eye, sometimes with a laser. A small tool is put in to break up the cataract and gently suction it out through the opening created. Then they put in the new lens, made of plastic, silicone, or acrylic, and close the incision. Surgical procedures namely phacoemulsification and minor incision cataract surgery (SICS) are widely used for cataract surgeries; the former is the latest development in cataract surgeries and is less time-consuming. If both eyes are affected, two surgeries are done separately.

Risk factors associated with development of senile cataract

Background: Cataract is the most common cause of reversible blindness worldwide, which has been associated with various causative risk factors. Hence, we aim to study the factors that might play a role in cataractogenesis. Material and methods: A total of 240 eyes of 240 subjects were included for the study, which consisted of 120 cases with age-related cataract and 120 age-matched controls, and in them various factors like blood pressure, body mass index (BMI), smoking, sun exposure, and serum cholesterol were studied. Results: A statistically significant difference between the two groups was found with respect to smoking profile (p = 0.007), sun exposure (p = 0.001), and serum cholesterol (p 0.05) was observed. Conclusion: Higher cholesterol levels, increased sun exposure, and smoking habit play a role in the development of senile cataract, and these are modifiable risk factors. Hence, control of these might help in delaying formation and progression of cataract.

COMPARATIVE STUDY OF BIOCHEMICAL PARAMETERS AMONG ELDERLY PATIENTS WITH CATARACT

Background: Cataract is among the most common ocular morbidity seen among elderly patients, it incidence is related to the aging process. It is a ocular morbidity and result in decrease the eye sight. Incidence of cataract related to aging process is generally seen in patients who are aged above 45 years of age. In previous researches it was estimated that approximately seventy five percent of general population above the 70 years of age has reported to suffer from lens opacity or cataract.
 Material & Methods: Patients who were presenting with nuclear or cortical or posterior sub-capsular cataracts along with healthy age and gender matched controls were enrolled from outdoor and from ward by simple random sampling. Clearance from Institutional Ethics Committee was taken before start of study. Written informed consent was taken from each study participant.
 Results: On the assessment of serum sodium levels it was found that mean serum sodium levels were 144.12 ± 2.43 meq/l in the cataract group and mean serum sodium levels were 139.37±3.4 meq/l in the age matched controls. This difference among both the groups was statistically significant (P value <0.05). On the assessment of serum potassium levels, it was found that mean serum potassium levels were 4.32 ± 0.11 meq/l in the cataract group and mean serum potassium levels were 4.10 ± 0.16 meq/l in the age matched controls. This difference among both the groups was statistically non-significant (P value >0.05).
 Conclusion: We concluded from the present study that the higher prevance of raised serum sodium levels in patients of senile cataract. We found that any alteration in serum electrolyte concentration leads to alterations in aqueous humor’s electrolyte concentration and responsible for risk factor for development of senile cataract.
 Key words: senile cataract, serum sodium, serum potassium.

Nutritional and Antioxidant Potential of Common Vegetables in Pakistan

Vegetables contain many important antioxidants and nutrients. Daucus carota L (carrot) is rich in hydrophilic and lipophilic antioxidants and is a good source of carbohydrates, vitamins, and minerals such as Ca, Mg, P, and Fe. It shows anti-carcinogenic, antioxidant, and immune boosting properties. It also provides protection against muscular degradation and development of senile cataract and reduces the risk of many diseases in humans. The nutritional value of Cucurbita pepo Linn (pumpkin) is attributed to the high level of carotenoids, carbohydrates, vitamins, other minerals. Pumpkin due to the presence of vitamin B complex, Ca and P, provides protection against many acute and chronic diseases. Pumpkin peel and pulp are the good source of antioxidants, polyphenols, carotenoids, dietary fiber and minerals such as P and Fe. Pumpkin extract shows antioxidant, antimicrobial and other activities. Spinacia oleracea (spinach) is a good source of essential nutrients such as carotenoids, vitamins, and minerals (P, K, Mg). Its leaves contain carotenoids, polyphenols, flavonoids, and ascorbic acid. Fresh spinach extract shows antioxidant and antimicrobial activity. Solanum tuberosum (potato) is rich in starch, alkaloids, flavonoids, dietary fiber, and some other minerals (K, Mg, Fe). Potato helps to overcome chronic and acute diseases and has an impact on blood pressure and gut health.

Obesity and dyslipidemia: risk factors for development of senile cataract

Background: Cataract is a major cause of blindness and visual impairment worldwide.Obesity and dyslipidemia may act as risk factors for development and progression of senile cataract.Objective: To determine obesity and dyslipidemia as the risk factors for development of senile cataract.Methods: This case control study was conducted in the Department of Physiology, Dhaka Medical College, Dhaka from July 2014 to June 2015. For this study, 100 diagnosed senile cataract patients (DSC) of both sexes, aged 41-70 years, were selected by purposive sampling as study group from Department of Ophthalmology, Dhaka Medical College and one hundred noncataract healthy adult subjects (NCG) were recruited as control among the relatives and hospital staff through personal contact.The criteria for inclusions are BMI e” 25.0 kg/m² ,waist circumstances > 88 cm in female and >102 cm in male and waist hip circumference ratio W: H > 0.85 infemale and > in male 0.9.Person with cataract due to trauma, acute or chronic diarrhoea, kidney disease, history of taking calcium channel blockers, lipid lowering agents and steroid were excluded from this study. For assessing lipid profile TC, TAG, HDLC, LDL-C of all subjects were estimated by enzymatic method. For statistical analyses, unpaired Student’s ‘t’ test, and logistic regression were done to evaluate the risk factors. Odds ratios (OR) with 95% Confidence Intervals (CI) were provided.Results: In this study BMI, WC, W: H, TC, TAG, LDLC levels were significantly higher (P<0.001)and HDL-C level was significantly lower (P<0.001) in diagnosed senile cataract patients(DSC) as compared to non-cataract group(NCG).Conclusion: From the study results, it is concluded that obesity (higher BMI, WC,W: H) and dyslipidemia may act as risk factors for development of senile cataract.J Bangladesh Soc Physiol. 2018, June; 13(1): 29-34

Protective effects of carnosine on dehydroascorbate-induced structural alteration and opacity of lens crystallins: important implications of carnosine pleiotropic functions to combat cataractogenesis

The high level of dehydroascorbic acid (DHA) in the lenticular tissue is an important risk factor for the development of age-related cataracts. In this study, the effects of DHA on structure and function of lens crystallins were studied in the presence of carnosine using gel mobility shift assay, different spectroscopic techniques, and lens culture analysis. The DHA-induced unfolding and aggregation of lens proteins were largely prevented by this endogenous dipeptide. The ability of carnosine to preserve native protein structure upon exposure to DHA suggests the essential role of this dipeptide in prevention of the senile cataract development. Although the DHA-modified α-crystallin was characterized by altered chaperone activity, functionality of this protein was significantly restored in the presence of carnosine. The increased proteolytic instability of DHA-modified lens proteins was also attenuated in the presence of carnosine. Furthermore, the assessment of lens culture suggested that DHA can induce significant lens opacity which can be prevented by carnosine. These observations can be explained by the pleiotropic functions of this endogenous and pharmaceutical compound, notably by its anti-glycation and anti-aggregation properties. In summary, our study suggests that carnosine may have therapeutic potential in preventing senile cataracts linked with the increased lenticular DHA generation, particularly under pathological conditions associated with the oxidative stress.

Role of Malondialdehyde (MDA) in senile cataract

Cataract is characterized partial or complete loss of transparency of the lens that leads to loss of vision. Globally, cataract associated blindness is a major cause of morbidity in developing countries. The cataractogenesis is affected by a number of factors with redox imbalance at the top of list. This imbalance results either from an increased generation of free radicals and/or decreased production of antioxidants. The end products of lipid peroxidation are both mutagenic and carcinogenic. One such product, malondialdehyde (MDA) reacts with deoxyadenosine and deoxyguanosine in DNA, to form DNA adducts. Its role in cataractogenesis is due to its cross linking ability. The present study analyzed the role of MDA in the development of senile cataract. Its level was measured in 75 randomly selected senile cataract patients of different age groups and matched against suitable controls. The study found statistically significant increased levels of MDA in cataract patients but not in controls, indicating an oxidative stress. The present study concluded that increased levels of MDA increased the susceptibility to cataractogenesis.

Assessment of structure, stability and aggregation of soluble lens proteins and alpha-crystallin upon non-enzymatic glycation: The pathomechanisms underlying cataract development in diabetic patients

Total soluble lens proteins (TSPs) and α-crystallin (α-Cry) were individually subjected to the long-term glycation in the presence of d-glucose. The glycated and non-glycated protein counterparts were incubated under different stress conditions and compared according to their structure, stability and aggregation propensity by various spectroscopic techniques and gel mobility shift analyses. Extensive glycation of the lens proteins was accompanied with structural alteration, reduction in their surface hydrophobicity and increment of their surface tension. Our results suggest that glycation causes lens crystallins to partially resist against structural alteration and aggregation/fibrillation under both thermal and thermochemical systems. The conformational stability of lens crystallins was increased upon glycation, showing the reason behind resistance of glycated proteins against stress-induced structural alteration and aggregation. Due to the resistance of glycated lens crystallins against aggregation, the role of this modification in development of senile cataract can be explained with the associated damaging consequences highlighted in this article.

SENILE CATARACT PATIENTS

Purpose: The current study was aimed at finding out the significance of serumelectrolytes and serum calcium levels in the development of senile cataract. Study Design:Case control study. Setting: Ghurki Trust Teaching Hospital, Lahore, Pakistan. Period: Jan2013 to June 2013. Methods: Total fifty patients with senile cataract and fifty controls wereselected. Clinical history and clinical diagnostic tests were performed by an ophthalmologist.Blood samples were drawn and serum stored at -20o C. Serum potassium and sodiumwere measured by Flame photometry. Serum chloride levels were estimated by quantitativedisplacement of thiocyanate by chloride. The estimation of calcium was done using photometryby CPC method. Statistical analysis was done by Statistical package for social sciences (SPSSversion 16.0). There were 31 females and 19 male (F:M = 1.63:1) patients. In the control group,there were 32 females and 18 males (F:M = 1.77:1). The age was ≥ 40 years in both patientsand control group. Results: Nuclear cataract was the commonest. Among all the analytes,only serum calcium levels were found to be significantly lower in patients (p value less than0.05 as compared to controls). While difference of sodium, potassium and chloride levelsbetween cases and controls was insignificant. (p values 0.49, 0.36, and 0.45 respectively).Conclusions: In Pakistan, serum electrolytes in cataract patients are not significantly differentfrom the controls while serum Calcium of cataract patients is significantly low when comparedwith the control group, indicating the possible role of low calcium level as a risk factor in thedevelopment of senile cataract.

English

Purpose: The current study was aimed at finding out the significance of serumelectrolytes and serum calcium levels in the development of senile cataract. Study Design:Case control study. Setting: Ghurki Trust Teaching Hospital, Lahore, Pakistan. Period: Jan2013 to June 2013. Methods: Total fifty patients with senile cataract and fifty controls wereselected. Clinical history and clinical diagnostic tests were performed by an ophthalmologist.Blood samples were drawn and serum stored at -20o C. Serum potassium and sodiumwere measured by Flame photometry. Serum chloride levels were estimated by quantitativedisplacement of thiocyanate by chloride. The estimation of calcium was done using photometryby CPC method. Statistical analysis was done by Statistical package for social sciences (SPSSversion 16.0). There were 31 females and 19 male (F:M = 1.63:1) patients. In the control group,there were 32 females and 18 males (F:M = 1.77:1). The age was ≥ 40 years in both patientsand control group. Results: Nuclear cataract was the commonest. Among all the analytes,only serum calcium levels were found to be significantly lower in patients (p value less than0.05 as compared to controls). While difference of sodium, potassium and chloride levelsbetween cases and controls was insignificant. (p values 0.49, 0.36, and 0.45 respectively).Conclusions: In Pakistan, serum electrolytes in cataract patients are not significantly differentfrom the controls while serum Calcium of cataract patients is significantly low when comparedwith the control group, indicating the possible role of low calcium level as a risk factor in thedevelopment of senile cataract.

UVA Light-excited Kynurenines Oxidize Ascorbate and Modify Lens Proteins through the Formation of Advanced Glycation End Products: IMPLICATIONS FOR HUMAN LENS AGING AND CATARACT FORMATION

Advanced glycation end products (AGEs) contribute to lens protein pigmentation and cross-linking during aging and cataract formation. In vitro experiments have shown that ascorbate (ASC) oxidation products can form AGEs in proteins. However, the mechanisms of ASC oxidation and AGE formation in the human lens are poorly understood. Kynurenines are tryptophan oxidation products produced from the indoleamine 2,3-dioxygenase (IDO)-mediated kynurenine pathway and are present in the human lens. This study investigated the ability of UVA light-excited kynurenines to photooxidize ASC and to form AGEs in lens proteins. UVA light-excited kynurenines in both free and protein-bound forms rapidly oxidized ASC, and such oxidation occurred even in the absence of oxygen. High levels of GSH inhibited but did not completely block ASC oxidation. Upon UVA irradiation, pigmented proteins from human cataractous lenses also oxidized ASC. When exposed to UVA light (320-400 nm, 100 milliwatts/cm(2), 45 min to 2 h), young human lenses (20-36 years), which contain high levels of free kynurenines, lost a significant portion of their ASC content and accumulated AGEs. A similar formation of AGEs was observed in UVA-irradiated lenses from human IDO/human sodium-dependent vitamin C transporter-2 mice, which contain high levels of kynurenines and ASC. Our data suggest that kynurenine-mediated ASC oxidation followed by AGE formation may be an important mechanism for lens aging and the development of senile cataracts in humans.

Contribution of PON1 Polymorphism in Senile Cataract among Diabetic and Non-Diabetic Egyptian Patients

Background: The development of senile cataract is a multifactorial process with oxidative stress and its sequelae are clearly involved in its etiology. Cataract is also one of the earliest secondary complications of diabetes mellitus. Paraoxonase (PON) enzyme is an antioxidant High-Density Lipoprotein (HDL)-associated enzyme. In mammals, three genes of paraoxonase, PON1, PON2, and PON3, have been identified. Aim: To assess the contribution of PON1-55 and PON1-192 gene polymorphisms as risk factors for senile cataract formation among diabeticand non-diabetic Egyptian patients. Methods: 132 Egyptian cataract patients (66 without diabetes and 66 with diabetes) and 106 subjects with matched age and sex free of cataract and diabetes control subjects were included in the present study using multiplex PCR for PON1-55 and PON1-192 gene polymorphisms followed by restriction fragment length polymorphism analysis. Results: The study revealed that there was a significant difference in PON1-55 genotypes; LL, LM and MM (p=0.0001) and in PON1-192 genotypes; QQ, QR and RR (p=0.0001) genotypes distribution among cataract patients with and without diabetes and controls. Also there was a significant difference in L and M (p=0.003) and in Q and R allele frequencies (p=0.005) among cataract patients with and without diabetes and controls. In addition there was a significant difference in the distribution of 55 LM/192 RR combined genotypes with the highest frequency in cataract diabetic subgroup (75%), while 55LL/192RR, 55LL/192QR and 55LM/192QR combined genotypes showed the highest frequencies among the control group (52.4%, 59.1% and 66.7% respectively). Conclusion: For the first time, we provide evidence that functional polymorphisms in the PON1 gene may influence the risk of cataract in both non-diabetic and diabetic subgroups in Egyptian populations, suggesting new clues that help to clarify the pathogenesis of cataract.

Age-related changes in the ocular lens of the albino rat

Background The eye lens is a minute organ with a complex structure that plays an indispensible role in the process of vision. Aim of the work This study was conducted to detect age-related structural changes that occur in the rat ocular lens and to correlate these changes with the development of senile cataract. Materials and methods Fifteen male albino rats were used in this study. They were divided into three groups: young, adult, and aged (1, 6, and 18 months, respectively). The animals’ lenses were removed, dissected, and processed for light and scanning electron microscopy. The width, thickness, and number of lens fibers were assessed using an image analyzer. Statistical analysis of data was carried out using analysis of variance and the Student t-test. Results In H&E-stained sections, the lens of aged rats was seen to be covered by a thick capsule and had a double layer of epithelial cells. The aged lens showed marked disorganization and vacuolation of nuclear fibers. Scanning electron microscopic study revealed irregularities of the lateral borders of the cortical fibers, folding of their surfaces, and few ball and socket interlocking patterns. The nuclear fibers showed microplicae with a decrease in their cross-sectioned areas. Statistical analysis revealed a significant increase in the number and width of the aged nuclear lens fibers and a significant decrease in their thickness, compared with younger ones. Conclusion Lens fibers undergo some structural changes as a result of aging in the form of irregularities in shape and arrangement, thinning and compaction. These changes could be correlated to age-related optical problems such as senile presbyopia and cataract.

Fluorescence diagnosis of the status of the human lens in vivo

We have studied fluorescence spectra of the human lens in vivo for healthy eyes and in different stages of senile cataract development. We propose a spectral criterion, the lens opacity index, allowing us to differentiate between stages of cataract development. We show a high correlation between the stage of cataract development and the opacity index. We propose an empirical expression for determining the stage of senile cataract development from the value of the lens opacity index. The technique has been clinically tested.

Reduced glutathione level and gsh-dependent enzyme activities in corticonuclear blocks of lenses in patients with senile cataract

Reduced compound glutathione (GSH) in the lens has the function to protect the thiol group of lens proteins, and as a substrate of glutathione peroxidase (GPx) and glutathione S-transferase (GST). Protein containing thiol groups is significant for the normal function of lens epithelium, i.e. enzymes Na-K-ATP-ase, thus influencing cell permeability. The relationship GSH/GSSG (oxidized glutathione) is normally high in the lens and other ocular tissue owing to the glutathione-redox cycle, which is localized in the lens epithelium and cortex surface. The aim of the study was to investigate non-enzymic factors of the antioxidant protection of non-protein and protein tiol, as well as to determine glutathione-dependent enzyme activity in the corticonuclear blocks of lenses in patients with senile cataract. Biochemical studies of lens were carried on 101 patients with senile cataract. According to cataract maturity degree, the patients were classified into two groups: senile incipient cataract (N = 41) and mature senile cataract (N = 60). GSH concentration was determined by Ellman's reagent. GPx activity was assayed with cumene hydroperoxide, and that of glutathione S-transferase by follow-up of glutathione conjugation and 1-chloro-2.4-dinitrobenzene rates. A significantly higher GSH concentration was found in the corticonuclear blocks of lenses with initial as related to mature cataract (p < 0.001). The activity of enzyme GPx and GST was considerably higher in the corticonuclear blocks of lenses with initial cataract (p < 0.001). With cataract progression, the quantity of available GSH, necessary for GPx and GST functioning, declined, so that the activity of these enzymes was also significantly decreased in mature cataract. The determined lower GSH concentration and antioxidant enzyme activity in corticonuclear blocks of lenses, particularly in cataract with a nuclear component, indicate the weakened antioxidant response of lens tissue during the development of senile cataract.

Association of Glutathione S-Transferases Polymorphisms (GSTM1andGSTT1) with Senile Cataract: A Meta-analysis

Glutathione S-transferase (GST) polymorphisms have been considered risk factors for the development of senile cataract. However, the results are not consistent. In this study, the authors conducted a meta-analysis to assess the association between GSTM1 and GSTT1 null genotypes and the risk for senile cataract. Published literature from PubMed, EMBASE, and other databases were retrieved. All studies evaluating the association between GSTM1/GSTT1 polymorphisms and senile cataract were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed- or random-effects model. Eleven studies on GSTM1 (1871 cases and 1267 controls) and five studies on GSTT1 (1180 cases, 706 controls) were included. Overall analysis showed that the association between GSTM1 null genotype and risk for senile cataract is not statistically significant (OR, 1.39; 95% CI, 0.99-1.94; P = 0.054) and that the association between GSTT1 null genotype and risk for senile cataract is not significant (OR, 1.09; 95% CI, 0.87-1.36; P = 0.454). Subgroup analysis showed that the association between GSTM1 null genotype and risk for senile cataract is statistically significant in Asians (OR, 1.66; 95% CI, 1.03-2.67; P = 0.039) but not in Caucasians (OR, 1.21; 95% CI, 0.74-1.96; P = 0.443). Similar results were observed for the association between GSTT1 null genotype and risk for senile cataract. The present meta-analysis suggested that GSTM1 and GSTT1 null genotypes are associated with increased risk for senile cataract in Asian populations but not in Caucasian populations. Given the limited sample size, the finding on GST polymorphisms merits further investigation.

Evaluation of serum zinc level and plasma SOD activity in senile cataract patients under oxidative stress

An imbalance in the systemic redox status leading to oxidative stress has been an important factor in development of senile cataracts, which is reflected by an increase in serum TBARS and a decrease in plasma SOD activity. Zinc has been an important cofactor required for structural stability of SOD. In the present study the role of serum zinc level and plasma SOD activity was analyzed in senile cataract patients showing significant oxidative stress. Serum TBARS, plasma SOD and serum zinc level was measured in thirty randomly selected senile cataract patients against properly matched controls. Although, the analysis of means showed a significant increase in serum TBARS and decrease in plasma SOD and serum zinc level in cases, but plasma SOD was found to be just significantly correlated (p=0.05) with the serum zinc only in the cases. The results of partial correlation studies and multiple regression analysis, also, showed only a significant correlation and predictable dependence between serum TBARS and plasma SOD, excluding any role of serum zinc level. The present study concludes that it is chiefly the plasma SOD activity, but not the serum zinc level, that determines the proneness of the patients for development of senile cataract.