Integrative Biology Journals

Natural Products and Bioprospecting ›› 2025, Vol. 15 ›› Issue (3): 24-24.DOI: 10.1007/s13659-025-00504-z

• ORIGINAL ARTICLES • Previous Articles     Next Articles

Activation of SIK1 by phanginin A regulates skeletal muscle glucose uptake by phosphorylating HADC4/5/7 and enhancing GLUT4 expression and translocation

Yu Shi1,2, Xing-de Wu3,4, Yanli Liu1,2, Yu Shen1, Hui Qu1, Qin-Shi Zhao3, Ying Leng1,2, Suling Huang1   

  1. 1. State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China;
    2. University of Chinese Academy of Sciences, Beijing, 100049, China;
    3. State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China;
    4. Key Laboratory of Ethnic Medicine Resource Chemistry, State Ethnic Affairs Commission & Ministry of Education, Yunnan Minzu University, Kunming, 650500, Yunnan, China
  • Received:2024-12-17 Accepted:2025-03-10 Online:2025-06-18 Published:2025-06-24
  • Supported by:
    This work was supported by grants from the National Natural Science Foundation of China (No. 82073905).

Activation of SIK1 by phanginin A regulates skeletal muscle glucose uptake by phosphorylating HADC4/5/7 and enhancing GLUT4 expression and translocation

Yu Shi1,2, Xing-de Wu3,4, Yanli Liu1,2, Yu Shen1, Hui Qu1, Qin-Shi Zhao3, Ying Leng1,2, Suling Huang1   

  1. 1. State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China;
    2. University of Chinese Academy of Sciences, Beijing, 100049, China;
    3. State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, China;
    4. Key Laboratory of Ethnic Medicine Resource Chemistry, State Ethnic Affairs Commission & Ministry of Education, Yunnan Minzu University, Kunming, 650500, Yunnan, China
  • 通讯作者: Ying Leng Email:E-mail:yleng@simm.ac.cn;Suling Huang Email:E-mail:slhuang@simm.ac.cn
  • 基金资助:
    This work was supported by grants from the National Natural Science Foundation of China (No. 82073905).

Abstract: Salt-inducible kinase 1 (SIK1) participates in various physiological processes, yet its involvement in regulating skeletal muscle glucose uptake remains unclear. Previously, we showed that phanginin A, a natural compound isolated from Caesalpinia sappan Linn, activated SIK1 to suppress gluconeogenesis in hepatocytes. Here, we aimed to elucidate the effects of SIK1 on skeletal muscle glucose uptake by using phanginin A. The C2C12 myotubes were incubated with phanginin A and then glucose uptake, mRNA levels, membrane GLUT4 content, phosphorylation levels of proteins in SIK1/HDACs and Akt/AS160 signaling pathways were determined. Phanginin A significantly promoted glucose uptake, while the pan-SIK inhibitor or knocking down SIK1 expression abolished the promotion. Further exploration showed that phanginin A enhanced GLUT4 mRNA levels by increasing histone deacetylase (HDAC) 4/5 phosphorylation and MEF2a mRNA and protein level, and knocking down SIK1 blocked these effects. Additionally, phanginin A induced HDAC7 phosphorylation, upregulated the junction plakoglobin (JUP) expression and Akt/AS160 phosphorylation. Knocking down JUP or SIK1 both attenuated the phanginin A-induced Akt/AS160 signaling and glucose uptake, suggesting that activation of SIK1 by phanginin A inactivated HDAC7 to increase JUP expression and Akt/AS160 phosphorylation, led to upregulation of GLUT4 translocation and glucose uptake. In vivo study showed that phanginin A increased phosphorylation levels of SIK1, HDAC4/5/7, Akt/AS160, and gene expression of MEF2a, GLUT4 and JUP, accompanied by elevated membrane GLUT4 and glycogen content in gastrocnemius muscle of C57BL/6 J mice, indicating enhanced glucose utilization. These findings reveal a novel mechanism that SIK1 activation by phanginin A stimulates skeletal muscle glucose uptake through phosphorylating HADC4/5/7 and the subsequent enhancement of GLUT4 expression and translocation.

Key words: SIK1, Phanginin A, Class IIa HDACs, Skeletal muscle, GLUT4, Glucose uptake

摘要: Salt-inducible kinase 1 (SIK1) participates in various physiological processes, yet its involvement in regulating skeletal muscle glucose uptake remains unclear. Previously, we showed that phanginin A, a natural compound isolated from Caesalpinia sappan Linn, activated SIK1 to suppress gluconeogenesis in hepatocytes. Here, we aimed to elucidate the effects of SIK1 on skeletal muscle glucose uptake by using phanginin A. The C2C12 myotubes were incubated with phanginin A and then glucose uptake, mRNA levels, membrane GLUT4 content, phosphorylation levels of proteins in SIK1/HDACs and Akt/AS160 signaling pathways were determined. Phanginin A significantly promoted glucose uptake, while the pan-SIK inhibitor or knocking down SIK1 expression abolished the promotion. Further exploration showed that phanginin A enhanced GLUT4 mRNA levels by increasing histone deacetylase (HDAC) 4/5 phosphorylation and MEF2a mRNA and protein level, and knocking down SIK1 blocked these effects. Additionally, phanginin A induced HDAC7 phosphorylation, upregulated the junction plakoglobin (JUP) expression and Akt/AS160 phosphorylation. Knocking down JUP or SIK1 both attenuated the phanginin A-induced Akt/AS160 signaling and glucose uptake, suggesting that activation of SIK1 by phanginin A inactivated HDAC7 to increase JUP expression and Akt/AS160 phosphorylation, led to upregulation of GLUT4 translocation and glucose uptake. In vivo study showed that phanginin A increased phosphorylation levels of SIK1, HDAC4/5/7, Akt/AS160, and gene expression of MEF2a, GLUT4 and JUP, accompanied by elevated membrane GLUT4 and glycogen content in gastrocnemius muscle of C57BL/6 J mice, indicating enhanced glucose utilization. These findings reveal a novel mechanism that SIK1 activation by phanginin A stimulates skeletal muscle glucose uptake through phosphorylating HADC4/5/7 and the subsequent enhancement of GLUT4 expression and translocation.

关键词: SIK1, Phanginin A, Class IIa HDACs, Skeletal muscle, GLUT4, Glucose uptake