Blockage of KHSRP-NLRP3 by MCC950 Can Reverse the Effect of Manganese-Induced Neuroinflammation in N2a Cells and Rat Brain

Abstract

Manganese neurotoxicity has been reported to cause a neurodegenerative disease known as parkinsonism. Previous reports have shown that the expression of the KH-type splicing regulatory protein (KHSRP), a nucleic acid-binding protein, and NLRP3 is increased upon Mn exposure. However, the relation between these two during Mn toxicity has not been fully deduced. The mouse neuroblastoma (N2a) and SD rats are treated with LPS and MnCl2 to evaluate the expression of KHSRP and NLRP3. Further, the effect of the NLRP3 inhibitor MCC950 is checked on the expression of NLRP3, KHSRP and pro-inflammatory markers (TNFα, IL-18 and IL-1β) as well as the caspase-1 enzyme. Our results demonstrated an increment in NLRP3 and KHSRP expression post-MnCl2 exposure in N2a cells and rat brain, while on the other hand with LPS exposure only NLRP3 expression levels were elevated and KHSRP was found to be unaffected. An increased expression of KHSRP, NLRP3, pro-inflammatory markers and the caspase-1 enzyme was observed to be inhibited with MCC950 treatment in MnCl2-exposed cells and rats. Manganese exposure induces NLRP3 and KHSRP expression to induce neuroinflammation, suggesting a correlation between both which functions in toxicity-related pathways. Furthermore, MCC950 treatment reversed the role of KHSRP from anti-inflammatory to pro-inflammatory.

Farnesol Protects against Cardiotoxicity Caused by Doxorubicin-Induced Stress, Inflammation, and Cell Death: An In Vivo Study in Wistar Rats

“…Increased oxidative stress and persistent increase in reactive oxygen species (ROS) stimulate lipid peroxidation and cause oxidative damage to myocytes, mitochondria, and cell membranes, leading to cardiotoxic manifestations [ 1 ]. After exposure to DOXO, oxidative stress is increased, leading to the expression of various transcription factors, such as nuclear factor kappa B (NF-κB), that further activate nucleotide-binding oligomerization domain-NOD-Like Receptor Protein 3 (NLRP3 inflammasome) [ 5 ]. This causes an increment in the release of proinflammatory cytokines from the myocardium, such as interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) [ 5 ].…”

“…After exposure to DOXO, oxidative stress is increased, leading to the expression of various transcription factors, such as nuclear factor kappa B (NF-κB), that further activate nucleotide-binding oligomerization domain-NOD-Like Receptor Protein 3 (NLRP3 inflammasome) [ 5 ]. This causes an increment in the release of proinflammatory cytokines from the myocardium, such as interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) [ 5 ]. In the pathogenesis of DOXO-induced cardiotoxicity, evidence shows that extrinsic and intrinsic pathways are involved.…”

Role of pyroptosis in the pathogenesis and treatment of diseases

“… 286 , 287 In an MPTP‐induced PD mouse model, the release of IL‐1β was induced significantly higher than in controls, IL‐1β levels can be inhibited by MCC950. 288 , 289 In microglia, α‐synuclein aggregates into Lewy bodies, and α‐synuclein aggregates activate NLRP3 to promote the release of proinflammatory cytokines such as IL‐1β. 290 In addition, inhibiting the occurrence of pyroptosis can improve behavioral disorders, reduce nigrostriatal dopaminergic degeneration, neuroinflammation, and inhibit the activation of proinflammatory microglia of PD rats.…”

“…Activation of the inflammasome has also been implicated in PD, recent studies have shown that suppression of the inflammasome and prevents dopaminergic neuron death in a 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐induced PD mouse model 286,287 . In an MPTP‐induced PD mouse model, the release of IL‐1β was induced significantly higher than in controls, IL‐1β levels can be inhibited by MCC950 288,289 . In microglia, α‐synuclein aggregates into Lewy bodies, and α‐synuclein aggregates activate NLRP3 to promote the release of proinflammatory cytokines such as IL‐1β 290 .…”

Possible Involvement of Cellular Pathway and Cytokines in Manganese Induced Neurotoxicity in Neuroblastoma Cells via KH–Type Splicing Regulatory Protein

“…The expression concentration of mRNA were compared to the GAPDH and the fold variation was quantified with the delta Ct formulae. The primers utilised for the qPCR were: KHSRP forward: 5'-TCCATCCTGCCTTAGTGGGT-3' KHSRP reverse: 5'-TAAGCCTCTGCACCCATCG-3' GAPDH forward: [27] 5'-CAGTGCCAGCCTCGTCCCGTAGA-3' GAPDH reverse: [27] 5'-CTGCAAATGGCAGCCCTGGTGAC -3' [28] Western blotting Post incubation, the phosphatase inhibitor cocktail (Sigma of USA, P2850), cell lysis buffer (9803), and proteinase inhibitor cocktail (Sigma of USA, P8340) were utilised to lyse cells. The protein levels were quantified with QuantiPro™ kit (QPBCA).…”