Phycocyanin Protects against High Glucose High Fat Diet Induced Diabetes in Mice and Participates in AKT and AMPK Signaling

Abstract

Phycocyanin is a type of marine natural product and functional food additive. Studies have demonstrated that phycocyanin has potential regulatory effects on glycometabolism, while its function and mechanism, especially in type 2 diabetes mellitus (T2DM), is still unclear. The aim of this study was to investigate the antidiabetic roles and underlying mechanism of phycocyanin in a high glucose high fat diet induced model of T2MD in C57BL/6N mice and a high-insulin-induced insulin-resistant model of SMMC-7721 cells. The results indicated that phycocyanin reduced high glucose high fat diet induced hyperglycemia as well as ameliorated glucose tolerance and histological changes in the liver and pancreas. Meanwhile, phycocyanin also significantly decreased the diabetes-induced abnormal serum biomarker variations, including triglyceride (TG), total cholesterol (TC), aspartate transaminase (AST), and glutamic-pyruvic transaminase (ALT), and increased the superoxide dismutase (SOD) content. Furthermore, the antidiabetic function of phycocyanin was exerted through activating the AKT and AMPK signaling pathway in the mouse liver, which was also verified in the insulin-resistant SMMC-7721 cells due to increased glucose uptake and activated AKT and AMPKα expression. Thus, the present study is the first to indicate that phycocyanin mediates antidiabetic function via activating the AKT and AMPK pathway in high glucose high fat diet induced T2DM mice and insulin-resistant SMMC-7721 cells, which lays a scientific theoretical basis for the potential treatment of diabetes and the utilization of marine natural products.

Nutraceutical Features of the Phycobiliprotein C-Phycocyanin: Evidence from Arthrospira platensis (Spirulina)

“…Thereafter, the positive effects of C-PC in the treatment of diabetes were confirmed by a further study conducted on both cellular and animal models [ 71 ]. It was observed that specifically in mice with type 2 diabetes mellitus (T2DM) that were treated orally with 200 mg kg −1 and in insulin-resistant cells, C-PC increased insulin sensitivity and the cellular use of glucose through the activation of AMP-activated protein kinase (AMPK), which, once active, promotes autophagy, and of serine/threonine kinase 1 (AKT), which is part of the phosphatidylinositol-3 kinase (PI3K) pathway and is relevant in the regulation of the glyco-metabolism [ 71 ].…”

“…The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/nu16111752/s1, Table S1: Effects of C-PC or PCB-B on different disease models [20,[24][25][26][27][28][29][30][31][32][33][34]36,[38][39][40][41][43][44][45][46][47][48][49][50][51][52][62][63][64][65][66][67][68]71,72,[76][77][78][79][80][81][82][85][86][87][88][90][91][92]...…”

Exploring the Benefits of Phycocyanin: From Spirulina Cultivation to Its Widespread Applications

“…This induces glycation and leads to the formation of macromolecules that accumulate in the heart, blood vessels, eyes, and kidneys [27,89]. Some studies have demonstrated that phycocyanin is an antidiabetic agent and has an antiglycation activity that reduces the side effects of diabetes [89][90][91][92]128]. Phycocyanin promoted glucose uptake in an insulin-resistant cell line [77] and inhibited αamylase and β-glucosidase in vitro, attenuating starch absorption [88,129,130].…”

Algae-Derived Natural Products in Diabetes and Its Complications—Current Advances and Future Prospects

“…AMPK is a key regulator of energy metabolism and glucose homeostasis. Several algae-derived compounds, such as fucoidan from the brown macroalga F. vesiculosus [ 120 ] and phycocyanin from the blue-green microalga Arthrospira platensis [ 121 ], have been found to activate AMPK. The activation of AMPK leads to increased glucose uptake, enhanced insulin sensitivity, and improved glycemic control.…”