Nutriomics of vitamin D and Tocotrienol rich fraction-vitamin E supplementation in insulin resistance induced-Zebrafish larvae model

The interaction between insulin resistance, oxidative stress and inflammation are the potential underlying mechanisms linking T2DM with neurodegeneration (ND). Although the precise mechanism remains unclear, T2DM can exacerbate this ND progression. Several adverse effects of antidiabetic upon long-term consumption have been documented. Therefore, alternative therapy with micronutrients has been suggested. Vitamin D is thought to sensitise insulin signalling, while vitamin E protects lipid oxidation by scavenging free radicals could modulate the pathophysiology of T2DM that is linked to ND. The study aims to investigate mechanistic pathways that overlap between micronutrients which is termed as nutriomics crosstalk, in attenuating the pathophysiology of T2DM. The insulin resistance model was induced in zebrafish larvae of 72-hr post-fertilization (hpf) with 250 nM insulin immersed in embryo media (E3 media) for 24-hr. To develop the persistence insulin resistance model, the zebrafish larvae were re-challenged with an additional 100 nM insulin at 96 hpf for 24-hr incubation. This model was validated by a glucose levels assay, qPCR analysis of selected genes (akt, pepck, zglut3 and claudin-5a) and Oil Red-O (ORO) staining of the yolk sac for lipid distribution. Treatment with vitamin D (1 M), TRF-vitamin E (1 -g/ml) and a combination of both were performed along with metformin (50 -M). The association between insulin resistance and neurodegeneration was validated by malondialdehyde (MDA), glutathione (GSH) assays, and next￾generation sequencing (NGS). The insulin resistance model was successfully developed with a significant increase in glucose levels and lipid accumulation shown by enlargement of yolk sac by ORO staining at 180-min in the insulin-resistant group. Insulin-signalling mediators, akt and pepck, were shown to significantly downregulated up to 400 min after insulin immersion (p<0.05). Meanwhile, claudin-5a assessed blood brain barrier (BBB) integrity showed significant deterioration after 40 and 400-min of post-insulin immersion as marker associating T2DM with ND. The process of revealing the micronutrient efficacy in the established disease model was elucidated in NGS. MDA levels exhibited significant differences in all experiment groups with the highest levels of MDA can be observed in the untreated insulin resistance group and the lowest of MDA level was in the combinations of both micronutrients. In parallel, GSH levels were significantly different in all groups but the highest level of GSH was in vitamin D group followed by the combination of vitamin D and TRF-vitamin E. Transcriptomic profiles analysis revealed 1556 upregulated genes and 2354 downregulated genes in vitamin D. TRF-vitamin E exhibited 639 upregulated genes and 202 downregulated genes. Metformin showed 1300 were upregulated and 200 were downregulated. Protein phosphorylation (APPB, p<0.05) was significantly difference in the insulin resistance treated with metformin but not in the micronutrients group. However, protein-protein interaction (PPI) networks revealed 18 genes were upregulated in all treatment groups. From the analysis, MAPK-Ca2+ signalling pathway could be a potential mechanism, which promotes glucose uptake in the cells incorporated by the vitamin D, TRF-vitamin E, and metformin. The presence of micronutrients was inevitable in restoring the insulin sensitivity and its functions as well as neutralizing free radicals, thereby, alleviating the progression of ND.

Text FPSK (p) 2024 28 - Declaration Form.pdf Restricted to Repository staff only Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (2MB) Text FPSK (p) 2024 28.pdf Restricted to Repository staff only Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (13MB) Text FPSK (p) 2024 28 - Full Text.pdf Available under License Creative Commons Attribution Non-commercial No Derivatives. Download (13MB)

Actions (login required)

View Item