Betok Fish (Anabas testudineus) Oil Decreases Inflammatory Cytokine through Increasing Vitamin D Level in Rats-induced Systemic Lupus Erythematosus

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disorder marked by the production of antibodies to the cell’s core components. Vitamin D is a steroid hormone that plays a role in the regulation of cell growth, proliferation, apoptosis, and regulation of the immune system. Vitamin D deficiency is a clinical condition that worsens clinical SLE. Betok fish commonly found in South Sumatra, Indonesia, is rich in vitamin D content AIM: The aim of the study was to explore the utilization of betok fish oil as a natural source of Vitamin D that could reduce inflammation in SLE. METHODS: A total of 30 male Wistar rats (200 ± 20 g) were obtained from Eureka Research Laboratory (Palembang, Indonesia). About 30 kg of betok fish were obtained from the Palembang Fish Auction Center, South Sumatra, Indonesia. Betok fish were extracted to obtain theirs oil by heating and centrifuging processes. Thirty male Wistar rats were randomly divided into the six groups: (1) Betok fish oil Group 1 0.1 mL/kg BW group, (2) Betok fish oil Group 2 0.2 mL/kg BW group, (3) Betok fish oil Group 3 0.4 mL/kgBW group, (4) normal control group, (5) negative control group, and (6) positive control group. Enzyme-linked immunosorbent assay (ELISA) method was used to assess ds-DNA levels and Vitamin D levels. Western blot assay was used to confirm the ELISA examination of pro-inflammatory cytokine (tumor necrosis factor-alpha [TNF-α]). All data were presented as mean ± standard deviation and all statistical analyzes are performed with the SPSS 25 (IBM) program. RESULTS: This study presented that the Vitamin D content in betok fish oil is quite high at 2021.43 IU/mL. That was higher than other Vitamin D regiments on the marketplace. Moreover, this research showed that giving fish oil at a dose of 0.4 mL/kg BW is more effective than the positive control in increasing serum Vitamin D levels. These results indicate the effectiveness of betok fish oil in increasing serum Vitamin D levels in SLE-induced rats. In addition, betok fish oil was able to reduce the expression of pro-inflammatory cytokine, TNF-alpha, in serum of SLE rats. CONCLUSION: Betok fish oil has efficacy in reducing levels of ds-DNA autoantibodies in SLE rats by decreasing the inflammatory response through upregulation of Vitamin D in serum