Rabbit Anti-Human AKT2 (Phospho-Ser474) polyclonal antibody

Fenofibrate (FF) protects against diabetic nephropathy (DN) in type 1 diabetic (T1 D) mice by upregulating the expression of fibroblast growth factor 21 (FGF21), leading to the activation of the Akt-mediated Nrf2 antioxidant pathways. Here, we examined which isoforms of Akt contribute to FF activation of FGF2I-mediated renal protection by examining the phosphorylation and expression of three isoforms, Akt1, Akt2, and Akt3. T1D induced by a single intraperitoneal dose of streptozotocin (STZ) resulted in reduced phosphorylation of one isoform, Akt2, but FF treatment increased renal Akt2 phosphorylation in these and normal mice, suggesting a potential and specific role for renal Akt2 in FF protection against T1D. This was further confirmed using in vitro cultured HK-2 human kidney tubule cells exposed to high glucose (HG) with siRNA silencing of the Akt2 gene and STZ-induced diabetic Akt2-knockout mice with and without 3-month FF treatment. In normal HK-2 cells exposed to HG for 24 hours, FF completely prevented cell death, reduced total Akt expression and glycogen synthase kinase (GSK)-3 beta phosphorylation, increased nuclear accumulation of Fyn, and reduced nuclear Nrf2 levels. These positive effects of FF were partially abolished by silencing Akt2 expression. Similarly, FF abolished T1D-induced renal oxidative stress, inflammation, and renal dysfunction in wild-type mice, but was only partially effective in Akt2-KO mice. Furthermore, FF treatment stimulated phosphorylation of AMPK alpha, an important lipid metabolism mediator, which in parallel with Akt2 plays an important role in FF protection against HG-induced HK-2 cells oxidative stress and damage. These results suggest that FF protects against DN through FGF21 to activate both Akt2/GSK-3 beta/Fyn/Nrf2 antioxidants and the AMPK pathway. Therefore, FF could be repurposed for the prevention of DN in T1D patients.

As one of three akt isoforms, akt2 plays a key role in the regulation of widely divergent cellular processes in mammals. However, its role and underlying mechanisms in zebrafish remain largely unknown. To elucidate the function of akt2 in zebrafish, we generated zebrafish lacking akt2 gene via CRISPR/Cas9 technology. Akt2-null zebrafish exhibit partial lethality and severe growth deficiency, which is different from those observed in akt2-null mice. Furthermore, akt2-null zebrafish display deficiency in fin ray development, but their cartilage is not affected. Similar to observations in akt2-nullmice, akt2-null zebrafish display impaired glucose homeostasis. However, in contrast to that in akt2-nullmice, insulin level is lower in akt2-null zebrafish, implicating the symptoms of type I diabetes exhibited in akt2-null zebrafish. In addition, transcriptome analysis reveals that the genes involved in metabolism and osteogenesis are disturbed in akt2-null zebrafish. Taken together, these data not only support an important role of akt2 in zebrafish survival, growth, bone development and glucose homeostasis, but also suggest that akt2 has divergent functions between mice and zebrafish, even though they are evolutionarily conserved. (C) 2017 Elsevier Ireland Ltd. All rights reserved.