Can J Diabetes 37 (2013) 401e407
Contents lists available at ScienceDirect
Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com
Original Research
Oxidative Stress-Associated Neuroretinal Dysfunction and Nitrosative Stress in Diabetic Retinopathy Lakshmi K. Mandal MS a, Subhadip Choudhuri PhD b, *, Deep Dutta MD c, Bhaskar Mitra MD d, Sunanda Kundu MSc e, Imran H. Chowdhury PhD b, Aditi Sen PhD b, Mitali Chatterjee PhD e, Basudev Bhattacharya MD b a
Regional Institute of Ophthalmology, Kolkata, India Department of Biochemistry, Dr. B C Roy Post Graduate Institute of Basic Medical Education and Research, Kolkata, India c Department of Endocrinology and Metabolism, B C Roy Post Graduate Institute of Basic Medical Education and Research and Seth Sukhlal Kanoria Memorial Hospital, Kolkata, India d Department of Pathology, Midnapore Medical College, Paschim Midnapore, India e Department of Pharmacology, Dr. B C Roy Post Graduate Institute of Basic Medical Education and Research, Kolkata, India b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 21 February 2013 Received in revised form 18 May 2013 Accepted 22 May 2013
Objective: The present study was intended to investigate whether oxidative stress is the key regulator to alter neuroretinal biochemical homeostasis and in turn aggravate the process of diabetic retinopathy by inducing nitrosative stress in the retinal neurovascular unit. Methods: Peripheral blood mononuclear cell reactive oxygen species level was measured by flow cytometry along with spectrophotometric detection of malondialdehyde (MDA) and glutamate from serum or plasma and a vitreous sample of study groups (i.e. subjects with proliferative diabetic retinopathy [PDR], type 2 diabetes without retinopathy [DNR] and healthy controls [HCs]). Further, nitrosative stress assessment was performed by spectrophotometric and enzyme-linked immunosorbent assay-based detection of serum and vitreous nitrite and nitrotyrosine concentrations, respectively. Results: The plasma glutamate level remains insignificant between subjects with PDR and DNR (p¼0.505) or in HC (p¼0.1344) individuals. However, serum MDA (p¼0.0004), nitrite (p¼0.0147) and nitrotyrosine (p¼0.0129) were found to be strikingly higher among PDR subjects compared with the DNR group. Significantly increased levels of peripheral blood mononuclear cell reactive oxygen species (p
Contents lists available at ScienceDirect
Canadian Journal of Diabetes journal homepage: www.canadianjournalofdiabetes.com
Original Research
Oxidative Stress-Associated Neuroretinal Dysfunction and Nitrosative Stress in Diabetic Retinopathy Lakshmi K. Mandal MS a, Subhadip Choudhuri PhD b, *, Deep Dutta MD c, Bhaskar Mitra MD d, Sunanda Kundu MSc e, Imran H. Chowdhury PhD b, Aditi Sen PhD b, Mitali Chatterjee PhD e, Basudev Bhattacharya MD b a
Regional Institute of Ophthalmology, Kolkata, India Department of Biochemistry, Dr. B C Roy Post Graduate Institute of Basic Medical Education and Research, Kolkata, India c Department of Endocrinology and Metabolism, B C Roy Post Graduate Institute of Basic Medical Education and Research and Seth Sukhlal Kanoria Memorial Hospital, Kolkata, India d Department of Pathology, Midnapore Medical College, Paschim Midnapore, India e Department of Pharmacology, Dr. B C Roy Post Graduate Institute of Basic Medical Education and Research, Kolkata, India b
a r t i c l e i n f o
a b s t r a c t
Article history: Received 21 February 2013 Received in revised form 18 May 2013 Accepted 22 May 2013
Objective: The present study was intended to investigate whether oxidative stress is the key regulator to alter neuroretinal biochemical homeostasis and in turn aggravate the process of diabetic retinopathy by inducing nitrosative stress in the retinal neurovascular unit. Methods: Peripheral blood mononuclear cell reactive oxygen species level was measured by flow cytometry along with spectrophotometric detection of malondialdehyde (MDA) and glutamate from serum or plasma and a vitreous sample of study groups (i.e. subjects with proliferative diabetic retinopathy [PDR], type 2 diabetes without retinopathy [DNR] and healthy controls [HCs]). Further, nitrosative stress assessment was performed by spectrophotometric and enzyme-linked immunosorbent assay-based detection of serum and vitreous nitrite and nitrotyrosine concentrations, respectively. Results: The plasma glutamate level remains insignificant between subjects with PDR and DNR (p¼0.505) or in HC (p¼0.1344) individuals. However, serum MDA (p¼0.0004), nitrite (p¼0.0147) and nitrotyrosine (p¼0.0129) were found to be strikingly higher among PDR subjects compared with the DNR group. Significantly increased levels of peripheral blood mononuclear cell reactive oxygen species (p
