Leukocyte Lipid Peroxidation, Superoxide Dismutase and Catalase Activities of Type 2 Diabetic Patients with Retinopathy

Increased oxidative stress might play an important role in the initiation and progression of diabetic complications. The present study has been undertaken to investigate whether there is any relationship between retinopathy degree and leukocyte superoxide dismutase (SOD) and catalase (CAT) activities and lipid peroxidation (LPO) in diabetic individuals with type 2 diabetic retinopathy. Patients were groupped with respect to the degree of retinopathy. Leukocyte malondialdehyde (MDA) levels, and SOD and CAT activities were measured in patients with type 2 diabetes mellitus (n=41) and nondiabetic healthy controls (n=23). Leukocyte LPO of the type 2 diabetic patients with retinopathy was significantly increased (p< 0.001), whereas SOD and CAT activities were decreased (p<0.001 and p<0.001, respectively) compared to those of controls. MDA concentrations rose while SOD and CAT activities fell with increasing severity of diabetic retinopathy, altough there was no significant difference in comprasion of the parameters mentioned above between the diabetic patients with and without retinopathy. Our results show that leukocytes in patients with type 2 diabetic retinopathy are affected by oxidative stress which might be contribute to pathogenesis of diabetic retinopathy. Prospective studies are needed to evaulate the relationship between the leukocyte antioxidants status and DR.

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Association of Fenofibrate and Diabetic Retinopathy in Type 2 Diabetic Patients: A Population-Based Retrospective Cohort Study in Taiwan

Medicina ◽

10.3390/medicina56080385 ◽

2020 ◽

Vol 56 (8) ◽

pp. 385

Author(s):

Ying-Chieh Lin ◽

Yu-Ching Chen ◽

Jorng-Tzong Horng ◽

Jui-Ming Chen

Keyword(s):

Diabetic Retinopathy ◽

Cohort Study ◽

Laser Treatment ◽

Population Based ◽

Hypoglycemic Agents ◽

Diabetic Patients ◽

Type 2 Diabetic Patients ◽

Significant Difference ◽

Type 2 Diabetic

Background and Objectives: Fenofibrate, a PPAR-α agonist, has been demonstrated to reduce the progression of diabetic retinopathy (DR) and the need for laser treatment in a FIELD (Fenofibrate Intervention and Event Lowering in Diabetes) study. However, in the subgroup of patients without pre-existing DR, there was no significant difference in the progression of DR between the fenofibrate group and the placebo group. In this study, we aim to investigate whether fenofibrate can decrease the risk of incident DR in a population-based cohort study of type 2 diabetic patients in Taiwan. Materials and Methods: A total of 32,253 type 2 diabetic patients without previous retinopathy were retrieved from 892,419 patients in 2001–2002. They were then divided into two groups based on whether they were exposed to fenofibrate or not. The patients were followed until a diagnosis of diabetic retinopathy was made or until the year 2008. Results: With a follow-up period of 6.8 ± 1.5 years and 5.4 ± 2.6 years for 2500 fenofibrate users and 29,753 non-users, respectively, the Cox proportional hazard regression analysis revealed that the hazard ratio (HR) of new onset retinopathy was 0.57 (95% CI 0.57–0.62, p < 0.001). After adjusting for hypertension; the Charlson comorbidity index (CCI); and medications such as angiotensin-converting enzyme inhibitors (ACE-I), angiotensin receptor blockers (ARB), anticoagulants, gemfibrozil, statins, and hypoglycemic agents, the adjusted HR was 0.75 (95% CI 0.68–0.82, p < 0.001). The need for laser treatment has an HR and adjusted HR of 0.59 (95% CI 0.49–0.71, p < 0.001) and 0.67 (95% CI 0.56–0.81, p < 0.001), respectively. Conclusion: Our study showed that the long-term and regular use of fenofibrate may decrease the risk of incident retinopathy and the need for laser treatment in type 2 diabetic patients. Since there are limitations associated with our study, further investigations are necessary to confirm such an association.

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Effects of Vitamin E on Fasting and Postprandial Oxidative Stress, Inflammatory Markers, Glucose Status, Insulin Resistance, Blood Pressure and Pulse Rate in Type-2 Diabetic Patients: A Randomized Clinical Trial

Galen Medical Journal ◽

10.31661/gmj.v4i3.333 ◽

2015 ◽

Vol 4 (3) ◽

pp. 67-74

Author(s):

Najmeh Hejazi ◽

Mohammad Hossein Dabbaghmanesh ◽

Zohreh Mazloom ◽

Arash Dashtabi

Keyword(s):

Oxidative Stress ◽

Blood Pressure ◽

Vitamin E ◽

Pulse Rate ◽

Diabetic Patients ◽

Short Term ◽

Type 2 Diabetic Patients ◽

Significant Difference ◽

Type 2 Diabetic

Background: Atherosclerosis is one of the prevalent complications in diabetic patients. Increased free radical levels in diabetes activate stress-sensitive signaling pathway, resulting in this outcome. This study examines the effect of short-term supplementation of vitamin E on different biochemical markers in type 2 diabetic patients to prevent from atherosclerosis. Materials and Methods: In this single-blind placebo controlled trial, 30 type 2 diabetic patients were randomly divided into two groups of study to receive vitamin E (400IU) or identical placebo capsules daily for 6 weeks. Serum level of lipoproteins, glucose, insulin, malondialdehyde (MDA), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs CRP), pulse rate and blood pressure were measured in fasting and postprandial (after a fatty meal) states before and after six weeks of supplementation. Results: There was not any significant difference in fasting and postprandial lipid profile (Triglyceride, HDL-, LDL- and total Cholesterol), glucose, insulin and HOMA-IR after six weeks of intervention between the two groups. However, results of our study showed a significant decrease in fasting and postprandial MDA levels and postprandial pulse rate and a significant increase in fasting IL-6 in vitamin E group compared to the controls after supplementation. There were no significant differences between the groups in other markers. Conclusion: This study suggests that short term supplementation of vitamin E can reduce oxidative stress in fasting and postprandial states in type 2 diabetic patients and may prevent diabetic complications; in addition, increment of IL-6 after supplementation may play a role in attenuating Type 2 diabetes by anti-inflammatory effects.[GMJ. 2015;4(3):67-74]

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Controlled diabetes amends oxidative stress as mechanism related to severity of diabetic retinopathy

Scientific Reports ◽

10.1038/s41598-021-96891-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rania Fahmy ◽

Nouf M. Almutairi ◽

May N. Al-Muammar ◽

Ramesa Shafi Bhat ◽

Nadine Moubayed ◽

...

Keyword(s):

Oxidative Stress ◽

Diabetic Retinopathy ◽

Lipid Peroxide ◽

Treatment Modalities ◽

Diabetic Patients ◽

Ophthalmological Examination ◽

Type 2 Diabetic Patients ◽

Group 3 ◽

Type 2 Diabetic

AbstractOxidative stress is a well-accepted etiological mechanism that contributes to neuronal dysfunction. Role of oxidative stress as a mechanism of retinopathy in controlled type 2 diabetic patients was evaluated. Participants were divided into three groups: Group 1 as 30 normal eyes of 15 subjects, Group 2 comprised 24 eyes of 12 diabetic patients without retinopathy and Group 3 comprised 23 eyes of 12 diabetic patients with different grades of retinopathy (8 eyes with maculopathy). A complete ophthalmological examination was performed. Oxidative stress markers were measured in blood. Macular thickness was different in all quadrants among all groups and showed a tendency to increase in Group 3 due to diabetic retinopathy with insignificant changes in parapapillary retinal nerve fiber layer thickness although thinning was noted also with retinopathy. Non-significant differences in GST and lipid peroxide levels were observed between the three studied groups, whereas vitamin C and GSH levels were higher in diabetic patients when compared to those in controls. As oxidative stress, hyperglycemia and local inflammation are involved in the pathogenesis of DR, the present study proved that the progressive damage can be retarded in controlled type 2 diabetic patients using different treatment modalities that abated oxidative stress.

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