27-Hydroxycholesterol Contributes to Lysosomal Membrane Permeabilization-Mediated Pyroptosis in Co-cultured SH-SY5Y Cells and C6 Cells

Abstract

Purpose : Emerging evidence suggests that 27-Hydroxycholesterol (27-OHC) causes neurodegenerative diseases through the induction of cytotoxicity and cholesterol metabolism disorder. The objective of this study is to determine the impacts of 27-OHC on lysosomal membrane permeabilization (LMP) and pyroptosis in neurons in the development of neural degenerative diseases. Methods : In this study, SH-SY5Y cells and C6 cells were co-cultured in vitro to investigate the influence of 27-OHC on the function of lysosome, LMP and pyroptosis related factors in neuron. Lyso Tracker Red (LTR) was used to detect the changes of lysosome pH, volume and number. Acridine orange (AO) staining was also used to detect the LMP in neurons. Then the morphological changes of cells were observed by a scanning electron microscope (SEM). The content of lysosome function associated proteins [including Cathepsin B (CTSB), Cathepsin D (CTSD), lysosomal-associated membraneprotein-1 (LAMP-1), LAMP-2] and the pyroptosis associated proteins [including nod-like recepto P3 (NLRP3), gasdermin D (GSDMD), caspase-1 and interleukin (IL)-1β] were detected through Western blot. Results : Results showed higher levels of lysosome function associated proteins, such as CTSB ( p < 0.05), CTSD ( p < 0.05), LAMP-1 ( p < 0.01), LAMP-2; p < 0.01) in 27-OHC treated group than that in the control group. AO staining and LTR staining showed that 27-OHC induced lysosome dysfunction with LMP. Content of pyroptosis related factor proteins, such as GSDMD ( p < 0.01), NLRP3 ( p < 0.001), caspase-1 ( p < 0.01) and IL-1β ( p < 0.01) were increased in 27-OHC treated neurons. Additionally, CTSB was leaked through LMP into the cytosol and induced pyroptosis. Results from the present study also suggested that the CTSB is involved in activation of pyroptosis. Conclusion : Our data indicate that 27-OHC contributes to the pathogenesis of cell death by inducing LMP and pyroptosis in neurons.

Neuroprotective Effects of Necrostatin-1 Against Oxidative Stress–Induced Cell Damage: an Involvement of Cathepsin D Inhibition

“…Activation of this enzyme participates in another form of cell damage, namely pyroptosis (Espinosa-Oliva et al 2019;Wang et al 2019). Since previous data showed the activation of this proinflammatory protease in neuronal cell type, including SH-SY5Y cells and neuroprotective potency of its inhibitors (Chen et al 2019;Knaryan et al 2014;Nath et al 1996;Zhao et al 2019a, b), it is highly probable that this mechanisms could be responsible for synergistic protective action of Nec-1 and curcumin against H 2 O 2 -evoked cell damage, observed in the present study.…”

Altered Circulating Free Oxysterols in Mild Cognitive Impairment: Relationship to Diet, Lipids and Genetics

“…Saeed et al [34] and Crick et al [31] have demonstrated that the concentration of 7α-hydroxy-3-oxo-4cholestenoic acid was remarkably elevated in CSF both from patients with a dysfunctional BBB and neurodegenerative disease including AD and Parkinson's disease (PD), or amyotrophic lateral sclerosis (ALS), which may be likely to re ect increased brain accumulation of 27-hydroxycholesterol as a result of damaged BBB integrity and increased serum levels of 27-hydroxycholesterol in MCI patients. The key role of 27-hydroxycholesterol in AD pathogenesis has been strongly supported by our previous animal and cellar research, pointing to the involvement of 27-hydroxycholesterol in the pro-in ammatory molecule release [35], oxidative stress [36], lysosomal membrane permeabilization and pyroptosis [37], synaptic dysfunction [38] and Aβ production [39]. We thus discovered and validated serum 27-hydroxycholesterol and 7α-hydroxy-3-oxo-4-cholestenoic acid as diagnostic biomarkers in MCI.…”

Dopamine Reduced Pyroptosis and Improved Functional Recovery After Spinal Cord Injury&nbsp;

“…Pyroptosis is a pattern of cell death, which is consistent with the release of proin ammatory cytokines such as IL-1β and IL-18 [44]. Pyroptosis is closely associated with neuronal loss [45]. Exposure to zinc may cause in ammasome-mediated pyroptosis in olfactory neurons [46]; and 27-hydroxycholesterol contributes to the pathogenesis of neuronal death by inducing pyroptosis [45].…”

“…Pyroptosis is closely associated with neuronal loss [45]. Exposure to zinc may cause in ammasome-mediated pyroptosis in olfactory neurons [46]; and 27-hydroxycholesterol contributes to the pathogenesis of neuronal death by inducing pyroptosis [45]. Valproic acid attenuated neuronal impairment that was due to ischemic/reperfusion injury by inhibiting pyroptosis [47].…”