Evaluation of Therapeutic Potential of Biogenic Selenium Nanoparticles in Rheumatoid Arthritis

Abstract

Rheumatoid Arthritis is the most chronic autoimmune disorder that affects 0.5-1 % of the world’s population and the incidence is more in females than in males. Current treatment options for Rheumatoid arthritis include, Non-steroidal Anti-inflammatory Drugs, corticosteroids and Disease Modifying Anti-Rheumatic Drugs. Intake of antioxidants such as vitamin C, E, zinc and selenium is usually recommended to decrease the oxidative stress in Rheumatoid Arthritis patients. It was found that patients of Rheumatoid Arthritis have deficiency of selenium which increases the production of Reactive Oxygen Species that is believed to be involved in pathogenesis of Rheumatoid Arthritis. Inadequate elimination of these Reactive Oxygen Species increases the disease severity and promotes inflammation and bone-resorption. In most of the cases, to meet the deficiency of selenium and reduce the oxidative stress supplements of selenium are given to Rheumatoid Arthritis patients. The major problem regarding use of these supplements is bioavailability and toxicity of selenium. Toxic effects of selenite, Se-

methylselenocysteine and selenomethionine are proved by many reports. To tackle this problem we carried out this research with the aim to make selenium therapy more effective and safe for Rheumatoid Arthritis patients. Nowadays, the conventional treatment strategies have been revolutionized due to introduction of nanotechnology and nano-materials. At Nano level (1-100nm) many fundamental properties of materials can be modified to get desired advantages. Among different nano-materials, metallic nanoparticles are of great significance due to their potential applications in the field of therapeutics. Foeniculum vulgare (fennel) is an important medicinal plant due to its various pharmacological properties such as anti-microbial, anti- inflammatory, anti-oxidant and anti-bone resorptive activity. Therefore, further use of fennel seed components i-e polyphenols for reduction of selenium salt into selenium nanoparticles can be fruitful in lowering selenium toxicity. This study covers Foeniculum vulgare mediated synthesis of selenium nanoparticles which is confirmed by spectrum peak at 261nm obtained by

UV/Vis spectrophotometer. Elemental analysis of nanoparticles was performed by Energy dispersive X-ray spectroscopy showing the presence of selenium nanoparticles in the sample. A strong physical adsorption of amine group (N-H) of proteins and hydroxyl group (O–H ) of phenols on surface of selenium nanoparticles, leading to a highly stable structure of these nanoparticles in water, has been confirmed by Fourier transform Infrared spectroscopy analysis. The X-Ray Diffraction pattern was analyzed for characterization of crystalline nature of selenium nanoparticles. Average diameter, morphology and particle size distribution was measured by Scanning Electron Microscopy analysis. Free radicle scavenging ability of selenium nanoparticles was estimated and compared with ascorbic acid by DPPH assay which showed significant increase in antioxidant activity of selenium nanoparticles with increase of concentration. Anti-bacterial effect of SeNPs was evaluated against Escherichia coli and Staphylococcus aureus by disc diffusion assay, which indicated visible zone of inhibition of cultured bacteria on nutrient agar. Cytotoxicity of selenium nanoparticles was monitored on Peripheral Blood Mononuclear Cells isolated from

Rheumatoid Arthritis patients and compared with sodium selenite by carring out MTT assay. The results showed that Foeniculum vulgare seed extract has the potential to reduce selenite ions to form stable selenium nanoparticles. Selenium nanoparticles exhibited good anti-bacterial activity against E.coli and S.aureus. Selenium nanoparticles possess considerable antioxidant activity comparable to that of standard antioxidant. Selenium nanoparticles are less toxic as compared to sodium selenite. Thus selenium nanoparticles can be used as an alternative to other selenium supplements by Rheumatoid Arthritis patients.