Spexin is a conserved peptide that functions as a neurotransmitter/neuromodulator and endocrine factor[1]. Spexin is a pleiotropic neuropeptide that can participate in the regulation of anxiety[2]. Spexin can regulate the lipogenesis and lipolysis processes in adipocytes, regulate insulin secretion, and also has cardioprotective properties[3, 4].
In vitro, INS-1E cells were treated with Spexin (1, 10, 100, 1000nM) for 1.5h. At 16mM glucose level, Spexin reduced the insulin secretion of cells, increased cell viability and proliferation, and increased the level of proliferating cell nuclear antigen (PCNA) protein[5]. Spexin (1μM) treatment of C2C12 cells for 24h promoted cell proliferation and differentiation[6].
In vivo, Spexin (50μg/kg/day) was treated by subcutaneous injection in high-fat diet rats for 8 weeks, which significantly reduced the body weight of rats and reduced the homeostasis model assessment of insulin resistance (HOMA-IR) value[7].
References:
[1] Porzionato A, Rucinski M, Macchi V, et al. Spexin expression in normal rat tissues[J]. Journal of Histochemistry & Cytochemistry, 2010, 58(9): 825-837.
[2] Zhuang M, Lai Q, Yang C, et al. Spexin as an anxiety regulator in mouse hippocampus: Mechanisms for transcriptional regulation of spexin gene expression by corticotropin releasing factor[J]. Biochemical and Biophysical Research Communications, 2020, 525(2): 326-333.
[3] Engin A. Adiponectin Resistance in Obesity: Adiponectin Leptin/Insulin Interaction[J]. Obesity and Lipotoxicity, 2024: 431-462.
[4] Ou W, Liu H, Chen C, et al. Spexin inhibits excessive autophagy‐induced ferroptosis to alleviate doxorubicin‐induced cardiotoxicity by upregulating Beclin 1[J]. British Journal of Pharmacology, 2024, 181(21): 4195-4213.
[5] Sassek M, Kolodziejski P A, Strowski M Z, et al. Spexin modulates functions of rat endocrine pancreatic cells[J]. Pancreas, 2018, 47(7): 904-909.
[6] Leciejewska N, Pruszyńska-Oszmałek E, Mielnik K, et al. Spexin Promotes the Proliferation and Differentiation of C2C12 Cells In Vitro—The Effect of Exercise on SPX and SPX Receptor Expression in Skeletal Muscle In Vivo[J]. Genes, 2021, 13(1): 81.
[7] Gu L, Ding X, Wang Y, et al. Spexin alleviates insulin resistance and inhibits hepatic gluconeogenesis via the FoxO1/PGC-1α pathway in high-fat-diet-induced rats and insulin resistant cells[J]. International journal of biological sciences, 2019, 15(13): 2815.
Spexin是一种保守的肽，起神经递质/神经调节剂和内分泌因子的作用[1]。Spexin是一种具有多效性的神经肽，可以参与焦虑调节[2]。Spexin能够调节脂肪细胞中的脂肪生成和脂肪分解过程，调节胰岛素分泌，还具有心脏保护特性[3, 4]。
在体外，Spexin（1, 10, 100, 1000nM）处理INS-1E细胞1.5h，在16mM葡萄糖水平下，Spexin减少了细胞的胰岛素分泌，增加了细胞活力和增殖，升高了增殖细胞核抗原（PCNA）蛋白水平[5]。Spexin（1μM）处理C2C12细胞24h，促进了细胞的增殖和分化[6]。
在体内，Spexin（50μg/kg/day）通过皮下注射治疗高脂饮食大鼠8周，显著减轻了大鼠体重，降低了稳态模型评估胰岛素抵抗（HOMA-IR）值[7]。