Zhiren Li1, Xiaoyun Zhang1, Tong Jin1, Jianyu Hao2. 1. Department of Gastroenterology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China. 2. Department of Gastroenterology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing 100020, China. Electronic address: haojianyu@ccmu.edu.cn.
Abstract
AIM: Pancreatic stellate cells (PSCs) are the main functional cells leading to pancreatic fibrosis. Nicotine is widely considered as an independent risk factor of pancreatic fibrosis, but the mechanism is still unclear. Our study was aimed to explore the effects of nicotine on human pancreatic stellate cells (hPSCs) and involved pathways. MATERIALS AND METHODS: Primary human PSCs were cultured and treated with nicotine (0.1 μM and 1 μM). The proliferation, apoptosis, α-SMA expression, extracellular matrix metabolism and autophagy of hPSCs were detected by CCK-8 assay, flow cytometry, real-time PCR and Western blotting analysis. The α7nAChR-mediated JAK2/STAT3 signaling pathway was also examined, and an α7nAChR antagonist α-bungarotoxin (α-BTX) was used to perform inhibition experiments. KEY FINDINGS: The proliferation, α-SMA expression and autophagy of hPSCs were significantly promoted by 1 μM nicotine. Meanwhile, the apoptosis of hPSCs was significantly reduced. The extracellular matrix metabolism of hPSCs was also regulated by nicotine. Moreover, the α7nAChR-mediated JAK2/STAT3 signaling pathway was activated by nicotine, this pathway and effects of nicotine can be blocked by α-BTX. SIGNIFICANCE: Our finding suggests that nicotine can promote activation of human pancreatic stellate cells (hPSCs) through inducing autophagy via α7nAChR-mediated JAK2/STAT3 signaling pathway, providing a new insight into the mechanisms by which nicotine affects pancreatic fibrosis.
AIM: Pancreatic stellate cells (PSCs) are the main functional cells leading to pancreatic fibrosis. Nicotine is widely considered as an independent risk factor of pancreatic fibrosis, but the mechanism is still unclear. Our study was aimed to explore the effects of nicotine on human pancreatic stellate cells (hPSCs) and involved pathways. MATERIALS AND METHODS: Primary human PSCs were cultured and treated with nicotine (0.1 μM and 1 μM). The proliferation, apoptosis, α-SMA expression, extracellular matrix metabolism and autophagy of hPSCs were detected by CCK-8 assay, flow cytometry, real-time PCR and Western blotting analysis. The α7nAChR-mediated JAK2/STAT3 signaling pathway was also examined, and an α7nAChR antagonist α-bungarotoxin (α-BTX) was used to perform inhibition experiments. KEY FINDINGS: The proliferation, α-SMA expression and autophagy of hPSCs were significantly promoted by 1 μM nicotine. Meanwhile, the apoptosis of hPSCs was significantly reduced. The extracellular matrix metabolism of hPSCs was also regulated by nicotine. Moreover, the α7nAChR-mediated JAK2/STAT3 signaling pathway was activated by nicotine, this pathway and effects of nicotine can be blocked by α-BTX. SIGNIFICANCE: Our finding suggests that nicotine can promote activation of human pancreatic stellate cells (hPSCs) through inducing autophagy via α7nAChR-mediated JAK2/STAT3 signaling pathway, providing a new insight into the mechanisms by which nicotine affects pancreatic fibrosis.