Yuan-Chii G Lee1, Yuh-Mou Sue2, Ching-Kuo Lee3, Huei-Mei Huang4, Jhin-Jyun He5, Yu-Shiou Wang6, Shu-Hui Juan7. 1. Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan. 2. Division of Nephrology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Nephrology, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan. 3. School of Pharmacy, Taipei Medical University, Taipei, Taiwan. 4. Graduate Institute of Medical Sciences, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. 5. Department of Physiology and Graduate Institute of Medical Sciences, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. 6. Graduate Institute of Medical Sciences, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Physiology and Graduate Institute of Medical Sciences, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. 7. Graduate Institute of Medical Sciences, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Physiology and Graduate Institute of Medical Sciences, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: juansh@tmu.edu.tw.
Abstract
BACKGROUND: We previously showed that 3-O-β-D-glucopyranosyl-(3R)-hydroxybutanolide (kinsenoside), a major compound of Anoectochilus formosanus, increased lipolysis through an AMP-activated protein kinase (AMPK)-dependent pathway. PURPOSE: To extend our previous finding, we investigated the in vivo and in vitro effects of kinsenoside on lipolysis and the involvement of cyclic AMP (cAMP)-dependent protein kinase A (PKA) and AMPK in kinsenoside-mediated lipolysis. STUDY DESIGN/ METHODS: Mice were fed a high-fat diet for six weeks to induce lipid deposition and then treated with 50 and 100 mg/kg kinsenoside for two weeks. The coordination of PKA and AMPK activation in lipolysis in C3H10T1/2 adipocytes was evaluated in vitro by using PKA and AMPK's corresponding inhibitors, oil-red O staining, a glycerol production assay, and Western blot analysis. RESULTS: Kinsenoside reduced body weight, fat pad mass, and hepatic lipid accumulation in obese mice, and concurrently increased the induction and activation of hormone-sensitive lipase (HSL), perilipin, adipose triglyceride lipase (ATGL), and carnitine palmitoyltransferase I (CPT1). Kinsenoside concentration-dependently increased PKA activation by increasing the phosphorylation of Ser/Thr-PKA substrates in vitro. These increases were accompanied by a reduction in fat accumulation. Using H89 and Rp-8-Br-cAMPs to inhibit PKA reduced the release of glycerol but did not alter the activation of peroxisome proliferator-activated receptor alpha or the expression of CPT1 or ATGL. By contrast, compound C, an AMPK inhibitor, inhibited CPT1 and ATGL expression in kinsenoside-treated C3H10T1/2 adipocytes. In addition, H89 caused the reactivation of AMPK downstream targets by increasing the levels of the active form of pAMPK-Thr172, suggesting that PKA negatively modulates AMPK activity. CONCLUSION: Kinsenoside increased HSL activation through PKA-mediated phosphorylation at Ser660/563 and concomitantly increased perilipin activation in lipolysis. These lipolytic effects of kinsenoside were validated using 6-Bnz-cAMPs, a PKA agonist. In this study, we demonstrated that in addition to AMPK, PKA also plays a crucial role in kinsenoside-mediated lipolysis.
BACKGROUND: We previously showed that 3-O-β-D-glucopyranosyl-(3R)-hydroxybutanolide (kinsenoside), a major compound of Anoectochilus formosanus, increased lipolysis through an AMP-activated protein kinase (AMPK)-dependent pathway. PURPOSE: To extend our previous finding, we investigated the in vivo and in vitro effects of kinsenoside on lipolysis and the involvement of cyclic AMP (cAMP)-dependent protein kinase A (PKA) and AMPK in kinsenoside-mediated lipolysis. STUDY DESIGN/ METHODS:Mice were fed a high-fat diet for six weeks to induce lipid deposition and then treated with 50 and 100 mg/kg kinsenoside for two weeks. The coordination of PKA and AMPK activation in lipolysis in C3H10T1/2 adipocytes was evaluated in vitro by using PKA and AMPK's corresponding inhibitors, oil-red O staining, a glycerol production assay, and Western blot analysis. RESULTS:Kinsenoside reduced body weight, fat pad mass, and hepatic lipid accumulation in obesemice, and concurrently increased the induction and activation of hormone-sensitive lipase (HSL), perilipin, adipose triglyceride lipase (ATGL), and carnitine palmitoyltransferase I (CPT1). Kinsenoside concentration-dependently increased PKA activation by increasing the phosphorylation of Ser/Thr-PKA substrates in vitro. These increases were accompanied by a reduction in fat accumulation. Using H89 and Rp-8-Br-cAMPs to inhibit PKA reduced the release of glycerol but did not alter the activation of peroxisome proliferator-activated receptor alpha or the expression of CPT1 or ATGL. By contrast, compound C, an AMPK inhibitor, inhibited CPT1 and ATGL expression in kinsenoside-treated C3H10T1/2 adipocytes. In addition, H89 caused the reactivation of AMPK downstream targets by increasing the levels of the active form of pAMPK-Thr172, suggesting that PKA negatively modulates AMPK activity. CONCLUSION:Kinsenoside increased HSL activation through PKA-mediated phosphorylation at Ser660/563 and concomitantly increased perilipin activation in lipolysis. These lipolytic effects of kinsenoside were validated using 6-Bnz-cAMPs, a PKA agonist. In this study, we demonstrated that in addition to AMPK, PKA also plays a crucial role in kinsenoside-mediated lipolysis.
Authors: Li Lu; Yuan Xiong; Ze Lin; Xiangyu Chu; Adriana C Panayi; Yiqiang Hu; Juan Zhou; Bobin Mi; Guohui Liu Journal: Front Pharmacol Date: 2022-10-04 Impact factor: 5.988