Ya-Ying Chang1, Ming-Chang Kao2, Jui-An Lin3, Tsung-Ying Chen4, Ching-Feng Cheng5, Chih-Shung Wong6, I-Shiang Tzeng7, Chun-Jen Huang8. 1. Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan; Department of Anesthesiology, Taipei Tzu Chi Hospital, Taipei, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan. 2. Department of Anesthesiology, Taipei Tzu Chi Hospital, Taipei, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan. 3. Department of Anesthesiology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. 4. School of Medicine, Tzu Chi University, Hualien, Taiwan; Department of Anesthesiology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan. 5. Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan; Department of Pediatrics, Buddhist Tzu Chi General Hospital, Hualien, Taiwan. 6. Department of Anesthesiology, Cathay General Hospital, Taipei, Taiwan. 7. Department of Medical Research, Taipei Tzu Chi Hospital, Taipei, Taiwan. 8. Department of Anesthesiology, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: huangcj1112@gmail.com.
Abstract
BACKGROUND: Nod-like receptor protein 3 (NLRP3) inflammasome is a multiprotein complex composed of NLRP3, caspase-1, and apoptosis-associated speck-like protein containing a caspase recruitment domain. Activation of NLRP3 inflammasome leads to interleukin-1β (IL-1β) upregulation and pyroptosis, a proinflammatory cell death characterized by increased cell size. Of note, calcium signaling is crucial for NLRP3 inflammasome activation. This study elucidated the effects of magnesium sulfate (MgSO4), a potent calcium antagonist, on modulating NLRP3 inflammasome. MATERIALS AND METHODS: THP-1 cells, the human monocytic leukemia cell line, were treated with lipopolysaccharide (LPS, 1 μg/ml) plus nigericin (5 μM) (the LPS + Nig group) and LPS plus nigericin plus MgSO4 (20 mM) [the LPS + Nig + M(20)] to facilitate investigations. Levels of IL-1β, pyroptosis, and NLRP3 inflammasome induction as well as intracellular calcium were assayed. RESULTS: IL-1β concentration of the LPS + Nig + M(20) group was significantly lower than the LPS + Nig group (P = 0.001). Cell size of the LPS + Nig + M(20) group was significantly smaller than the LPS + Nig group (P < 0.001). Level of pyroptotic cell death of the LPS + Nig + M(20) group was significantly lower than the LPS + Nig group (P = 0.004). NLRP3 mRNA and protein concentrations of the LPS + Nig + M(20) group were also significantly lower than the LPS + Nig group (P = 0.021 and P < 0.001). Similarly, apoptosis-associated speck-like protein containing a caspase recruitment domain speck formation ratio and caspase-1 concentration of the LPS + Nig + M(20) group were significantly lower than the LPS + Nig group (both P < 0.001). The change in intracellular calcium level of the LPS + Nig + M(20) group was significantly smaller than the LPS + Nig group (P = 0.001). CONCLUSIONS: MgSO4 inhibits NLRP3 inflammasome, IL-1β upregulation, and pyroptosis. The mechanism is consistent with decreased intracellular calcium levels.
BACKGROUND:Nod-like receptor protein 3 (NLRP3) inflammasome is a multiprotein complex composed of NLRP3, caspase-1, and apoptosis-associated speck-like protein containing a caspase recruitment domain. Activation of NLRP3 inflammasome leads to interleukin-1β (IL-1β) upregulation and pyroptosis, a proinflammatory cell death characterized by increased cell size. Of note, calcium signaling is crucial for NLRP3 inflammasome activation. This study elucidated the effects of magnesium sulfate (MgSO4), a potent calcium antagonist, on modulating NLRP3 inflammasome. MATERIALS AND METHODS: THP-1 cells, the human monocytic leukemia cell line, were treated with lipopolysaccharide (LPS, 1 μg/ml) plus nigericin (5 μM) (the LPS + Nig group) and LPS plus nigericin plus MgSO4 (20 mM) [the LPS + Nig + M(20)] to facilitate investigations. Levels of IL-1β, pyroptosis, and NLRP3 inflammasome induction as well as intracellular calcium were assayed. RESULTS: IL-1β concentration of the LPS + Nig + M(20) group was significantly lower than the LPS + Nig group (P = 0.001). Cell size of the LPS + Nig + M(20) group was significantly smaller than the LPS + Nig group (P < 0.001). Level of pyroptotic cell death of the LPS + Nig + M(20) group was significantly lower than the LPS + Nig group (P = 0.004). NLRP3 mRNA and protein concentrations of the LPS + Nig + M(20) group were also significantly lower than the LPS + Nig group (P = 0.021 and P < 0.001). Similarly, apoptosis-associated speck-like protein containing a caspase recruitment domain speck formation ratio and caspase-1 concentration of the LPS + Nig + M(20) group were significantly lower than the LPS + Nig group (both P < 0.001). The change in intracellular calcium level of the LPS + Nig + M(20) group was significantly smaller than the LPS + Nig group (P = 0.001). CONCLUSIONS:MgSO4 inhibits NLRP3 inflammasome, IL-1β upregulation, and pyroptosis. The mechanism is consistent with decreased intracellular calcium levels.
Authors: Sarah N Cross; Rachel A Nelson; Julie A Potter; Errol R Norwitz; Vikki M Abrahams Journal: Am J Reprod Immunol Date: 2018-04-30 Impact factor: 3.886