A marine drug: Astaxanthin alleviates the ultraviolet irradiation-induced impairment of visual acuity function in male adult zebrafish via the regulation of reactive retinal glial cell functions

Title : A marine drug: Astaxanthin alleviates the ultraviolet irradiation-induced impairment of visual acuity function in male adult zebrafish via the regulation of reactive retinal glial cell functions

Abstract:

Reactive retinal glial cells (RRGC) like Müller cells and microglia are important for retinal health, whereas impairment of RRGC function alters visual acuity functions. These cells are known to secrete neurotrophic and growth factors for the support of neuronal survival and regeneration. Furthermore, it also maintains the blood-retinal barrier function and regulates the retinal microenvironment. The marine drug i.e., astaxanthin (AST) is known to possess retinoprotective action. However, the role in the improvement of ultraviolet irradiation (UVI) induced dysfunction of visual acuity response in zebrafish. Hence, the present study focused on the evaluation of astaxanthin against the UVI-induced impairment of visual acuity function in male adult zebrafish with involvement of RRGC functions. The zebrafish was exposed the ultraviolet light B (UV-B; 301 nm) irradiation for 15 minutes. The AST (10 and 20 mg/L) and dexamethasone (DEX: 1 mg/L) were exposed for 21 consecutive days. DEX (reference drug) is known to protect Müller cells and protect the other retinal ganglion cells.  The UVI-induced changes of visual acuity functions were assessed by optokinetic response (OKR) and startle response (SR) tests on 0, 7, 14, and 21^st   days. The biomarkers of RRGC function, i.e., galectin-1 (a marker for microglia activation), an inflammatory marker i.e., tumor necrosis factor-alpha (TNF-α), and an oxidative stress marker i.e., reduced glutathione (GSH). The AST potentially attenuated the UVI-induced impairment of visual acuity function with the regulation of RRGC function along with a reduction of inflammatory markers and oxidative stress marker levels, which is similar to the DEX-treated group. Hence, AST may be used for the management of enhancement of visual acuity functions due to its regulation of RRGC functions, anti-inflammatory, and free radical scavenging actions.

Biography:

Dr. Arunachalam Muthuraman completed his Ph.D. in 2012 at Punjabi University, India. He joined as scientist-in-charge at Akal Toxicology Research Center and HOD in the Pharmacology Department at Akal College of Pharmacy. Later, he worked at JSS University, India. Currently, he is working at AIMST University, Malaysia. His research areas are diabetic retinopathy, neuropathic pain, Alzheimer's disease, and neurodegenerative disorders. He has published > 130 research articles in peer-reviewed Scopus & SCI-indexed journals. He received various prestigious awards and more than 2 million grants from various funding agencies. He patented instrumental design and utility products from India, UK, and Germany.