MiR-29c Inhibits TNF-α-Induced ROS Production and Apoptosis in Mouse Hippocampal HT22 Cell Line

Abstract

Recent reports have suggested that abnormal miR-29c expression in hippocampus have been implicated in the pathophysiology of some nervous system disease. However, many aspects underlying mechanism of miR-29c in regulating cellular functions in hippocampal neurons are not clear. In this study, HT22 cells were infected with lentivirus containing miR-29c or miR-29c sponge. Cell counting kit-8 (CCK8) and lactate dehydrogenase (LDH) assay kit were applied to evaluate cell viability and toxicity before and after TNF-α application. The intracellular reactive oxygen species (ROS) concentration were evaluated using dihydroethidium (DHE) staining and the mitochondrial membrane potential (MMP) was determined using Tetramethylrhodamine methyl ester (TMRM) staining. Cellular apoptosis was observed via TUNEL staining assay and Hoechst 33258 staining and measured by the expression of cleaved caspase-3, -8 and − 9. The expression of miR-29c and TNFR1, Bcl-2, Bax, TRADD and FADD was analyzed by PCR or WB. As a result, we found that miR-29c overexpression signi cantly attenuated decreases in cell viability, release of LDH and apoptosis in TNF-α-treated HT22 cells. Furthermore, the high expression of miR-29c can signi cantly prevented TNF-α-induced oxidative injuries via the decrease of intracellular ROS levels and the increase of MMP. TNF-α-induced increase in Bax and cleaved-caspase-9 and the decrease of Bcl-2 was attenuated after transfection of HT22 cells with miR-29c. Moreover, over-expression of miR-29c signi cantly inhibits the increased expression of TNFR1, TRADD, FADD, cleaved caspase-8 and − 3. However, in HT22 cells transfected with miR-29c sponge, TNF-α-induced cytotoxicity and oxidative stress, as well as elevated expression of TNFR1, TRADD and FADD were exacerbated. Our ndings indicated that miR-29c overexpression attenuates TNF-α-induced HT22 cells injury through inhibiting mitochondrial oxidative stress-induced apoptosis. In addition, TNF-αinduced TNFR1 activation, FADD association and caspase 8 recruitment may be impaired by miR-29c. Therefore, miR-29c might be a potential therapeutic target for the treatment of TNF-α-induced neurotoxicity.

Nicotinamide Phosphoribosyltransferase Positive Allosteric Modulators Attenuate Neuronal Oxidative Stress

“…Specifically, TNFα can induce ROS production in neurons via TNF receptor 1 (TNFR1) and subsequent NFκB-promoted gene expression of ROS-generating enzymes, such as iNOS and NOX2 . This has been demonstrated in HT-22 cell cultures, which further supports our use of the cell line to model the interaction between TNFα and OS …”

“…38 This has been demonstrated in HT-22 cell cultures, which further supports our use of the cell line to model the interaction between TNFα and OS. 39 Nicotinamide riboside (NR) treatment in AD mouse models has been shown to prevent oxidative DNA damage, decrease measures of activated astrocytes and microglia, and inhibit the upregulation of proinflammatory pathways, including the release of TNFα. 35,40 In a model of vascular dementia, 8 weeks of daily intraperitoneal NAD + administration attenuated microglial activation and TNFα mRNA expression and blunted increased ROS in the hippocampus and cortex.…”

MicroRNA-29a-5p Attenuates Oxygen-glucose Deprivation and Reoxygenation Injury in Astrocytes by Targeting Glycogen Synthase Kinase 3β

“…Regulating microRNAs in the BBB may alleviate CIRI in animal and in vitro models with OGD/R. [8][9][10][11][12][13][14][15][16][17][18] In this study, we found microRNA-29a-5p decreased in astrocytes after OGD/R. Increased microRNA-29a-5p alleviated astrocyte injury and induced phenotype shifting of astrocytes.…”

“…MicroRNA-29a, microRNA-29b, and microRNA-29c decreased expression in CIRI. 12–15 Knocking out microRNA-29a-5p increased microglia’s polarization and glutamate release, leading to an increase in infarct volume in the animal model of CIRI. 16 NADPH oxidase inhibitor reduced cerebral infarct volume and hemorrhagic transformation after mechanical reperfusion and increased the level of microRNA-29a-5p and microRNA-29c-3p in the rat ischemic tissue.…”

Zinc accumulation aggravates cerebral ischemia/reperfusion injury by promoting inflammation

“…Therefore, the expression changes of proinflammatory cytokines and anti-inflammatory cytokine in ischemic rats were studied at 6 and 24 h after reperfusion in this study. TNF-α is a key mediator in neuronal immunomodulatory system, and its abnormal expression plays an important role in various pathological processes (Lambertsen et al, 2012 ; Li B. et al, 2022 ). In the present study, very few TNF-α-positive cells were observed in the brain of the sham group, whereas TNF-α-positive cells was gradually upregulated in the ischemic penumbra of MCAO rats at 6 and 24 h after reperfusion, indicating that cerebral I/R resulted in increased expression of TNF-α.…”