MicroRNA miR-27b-3p regulate microglial inflammation response and cell apoptosis by inhibiting A20 (TNF-α-induced protein 3)

Background: Osteoarthritis (OA) is the most common joint disorder characterized by degeneration of the articular cartilage and joint destruction with an associated risk of mobility disability in elderly people. Although a lot of achievements have been made, OA is still regarded as an incurable disease. Therefore, the pathological mechanisms and novel therapeutic strategies of OA need more investigation. Methods: MTT assay was conducted to measure the viability of chondrocytes after LPS treatment. Cell apoptosis was analyzed by annexin V/propidium iodide labeling. ELISA was used to determine the concentrations of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in the culture supernatant of chondrocytes. The expression level of miR-155, IL-1β, FOXO3, TNF-α, IL-6, caspase-3, and caspase-9 in chondrocytes was analyzed by RT-qPCR or Western blot. Results: We found that LPS led to inflammatory responses, cell apoptosis, and increased miR-155 expression in human articular chondrocytes. Tanshinone IIA could inhibit LPS-induced inflammation and cell apoptosis of chondrocytes via regulating the expression of miR-155 and FOXO3. miR-155 directly targeted the 3′-UTR of FOXO3 to regulate its expression. Conclusions: Taken together, our data suggest tanshinone IIA ameliorates inflammation response in OA via inhibition of the miR-155/FOXO3 axis, and provide some evidences that tanshinone IIA could be designed and developed as a new promising clinical therapeutic drug for OA patients.

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Expression of miR-195 and its target gene Bcl-2 in human intervertebral disc degeneration and their effects on nucleus pulposus cell apoptosis

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02538-8 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Xue-Lin Lin ◽

Zhao-Yun Zheng ◽

Qing-Shan Zhang ◽

Zhen Zhang ◽

You-Zhi An

Keyword(s):

Cell Proliferation ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Rat Model ◽

Cell Apoptosis ◽

Intervertebral Disc Degeneration ◽

Target Gene ◽

Blank Group ◽

Tnf Α

Abstract Objective To investigate the expression of miR-195 and its target gene Bcl-2 in intervertebral disc degeneration (IVDD) and its effect on nucleus pulposus (NP) cell apoptosis. Methods The expressions of miR-195 and Bcl-2 in NP tissues of IVDD patients were quantified by qRT-PCR and western blotting, respectively. NP cells were divided into blank group, TNF-α group, TNF-α + miR-NC group, TNF-α + siBcl-2 group, and TNF-α + miR-195 inhibitors + siBcl-2 group. Cell proliferation was detected by MTT assay, cell apoptosis evaluated by flow cytometry, and mitochondrial membrane potential (MMP) tested by JC-1 staining. Moreover, the function of miR-195 on IVDD in vivo was investigated using a puncture-induced IVDD rat model. Results IVDD patients had significantly increased miR-195 expression and decreased Bcl-2 protein expression in NP tissues. The expression of miR-195 was negatively correlated with the expression of Bcl-2 in IVDD patients. Dual-luciferase reporter gene assay indicated that Bcl-2 was a target gene of miR-195. In comparison with blank group, TNF-α group showed decreased cell proliferation and MMP, increased cell apoptosis, upregulated expression of miR-195, Bax, and cleaved caspase 3, and downregulated Bcl-2 protein, while these changes were attenuated by miR-195 inhibitors. Additionally, siBcl-2 can reverse the protective effect of miR-195 inhibitors on TNF-α-induced NP cells. Besides, inhibition of miR-195 alleviated IVDD degeneration and NP cell apoptosis in the rat model. Conclusion MiR-195 was significantly upregulated in NP tissues of IVDD patients, and inhibition of miR-195 could protect human NP cells from TNF-α-induced apoptosis via upregulation of Bcl-2.

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Hypoxia-Induced S100A8 Expression Activates Microglial Inflammation and Promotes Neuronal Apoptosis

International Journal of Molecular Sciences ◽

10.3390/ijms22031205 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1205

Author(s):

Ji Sun Ha ◽

Hye-Rim Choi ◽

In Sik Kim ◽

Eun-A Kim ◽

Sung-Woo Cho ◽

...

Keyword(s):

Calcium Binding ◽

Neuronal Apoptosis ◽

Microglial Cells ◽

Molecular Pattern ◽

Extracellular Signal ◽

Tnf Α ◽

Cox 2 ◽

Necrosis Factor ◽

Microglial Inflammation ◽

Tlr4 Receptor

S100 calcium-binding protein A8 (S100A8), a danger-associated molecular pattern, has emerged as an important mediator of the pro-inflammatory response. Some S100 proteins play a prominent role in neuroinflammatory disorders and increase the secretion of pro-inflammatory cytokines in microglial cells. The aim of this study was to determine whether S100A8 induced neuronal apoptosis during cerebral hypoxia and elucidate its mechanism of action. In this study, we reported that the S100A8 protein expression was increased in mouse neuronal and microglial cells when exposed to hypoxia, and induced neuroinflammation and neuronal apoptosis. S100A8, secreted from neurons under hypoxia, activated the secretion of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6) through phosphorylation of extracellular-signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) in microglia. Also, phosphorylation of ERK via the TLR4 receptor induced the priming of the NLRP3 inflammasome. The changes in Cyclooxygenase-2 (COX-2) expression, a well-known inflammatory activator, were regulated by the S100A8 expression in microglial cells. Knockdown of S100A8 levels by using shRNA revealed that microglial S100A8 expression activated COX-2 expression, leading to neuronal apoptosis under hypoxia. These results suggested that S100A8 may be an important molecule for bidirectional microglia-neuron communication and a new therapeutic target for neurological disorders caused by microglial inflammation during hypoxia.

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Long Noncoding RNA SNHG1 Promotes Lipopolysaccharide-Induced Activation and Inflammation in Microglia via Targeting miR-181b

NeuroImmunoModulation ◽

10.1159/000514549 ◽

2021 ◽

pp. 1-11

Author(s):

Jun Dong ◽

Tingkai Fu ◽

Yunxue Yang ◽

Zhenxin Mu ◽

Xingang Li

Keyword(s):

Inflammatory Cytokines ◽

Long Noncoding Rna ◽

Calcium Binding ◽

Noncoding Rna ◽

Morphological Changes ◽

Luciferase Reporter ◽

Enzyme Linked Immunosorbent Assay ◽

Inflammation Response ◽

Tnf Α ◽

Cox 2

Introduction: Long noncoding RNA small nuclear host gene 1 (SNHG1) was involved in neuroinflammation in microglial BV-2 cells; however, its interaction with microRNA (miR)-181b in lipopolysaccharide (LPS)-induced BV-2 cells remained poor. Methods: BV-2 cells were treated with LPS and then were subjected to observation on morphology and immunofluorescence staining. After transfection, levels of inflammatory cytokines interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) were determined with enzyme-linked immunosorbent assay (ELISA). The potential binding sites between SNHG1 and miR-181b were confirmed using dual-luciferase reporter assay. Quantitative real-time polymerase chain reaction and Western blot were applied for detecting the mRNA and protein expressions of proinflammatory cytokines, ionized calcium-binding adapter molecule 1 (Iba1), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). Results: LPS led to the morphological changes and activation of BV-2 cells. The transfection of SNHG1 overexpression vector further promoted LPS-induced SNHG1 upregulation, inflammatory cytokines (IL-1β, IL-6, and TNF-α) generation and Iba-1, COX-2, and iNOS expressions, whereas silencing SNHG1 did the opposite. miR-181b functions as a downstream miRNA of SNHG1. In LPS-treated cells, the inhibition of miR-181b induced by SNHG1 promoted inflammation response and the expressions of Iba-1, COX-2, and iNOS. Conclusion: SNHG1 was involved in LPS-induced microglial activation and inflammation response via targeting miR-181b, providing another evidence of the roles of SNHG1 implicated in neuroinflammation of microglia.

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Methyl jasmonate reduces the inﬂammation and apoptosis of HK-2 cells induced by LPS by regulating the NF-κB pathway

10.22514/10.22514/sv.2021.079 ◽

2021 ◽

Keyword(s):

Cell Viability ◽

Methyl Jasmonate ◽

Cell Apoptosis ◽

Cell Model ◽

Tubular Epithelial Cell ◽

Cell Protein ◽

Epithelial Cell Line ◽

Tnf Α ◽

Iκbα Phosphorylation ◽

Anti Inflammatory

Background: Methyl jasmonate is a bioactive oxylipid that participates in the defense-related mechanisms of plants. The anti-inflammatory and anti-oxidative capacities of methyl jasmonate against lipopolysaccharide (LPS) induced arthritis have been widely investigated. However, the role of methyl jasmonate in LPS-induced cell model of tubular-interstitial nephritis (TIN) has not been reported. Methods: LPS (5 µg/mL) was applied to treat human renal tubular epithelial cell line (HK-2) for the establishment of TIN cell model. LPS-induced HK-2 was incubated with 10 or 20 µM methyl jasmonate, cell viability and apoptosis were assessed by MTT and flow cytometry. ELISA and qRT-PCR were performed to determine the levels of interleukin (IL)-1 beta (IL-1β), IL-6, IL-8 and tumor necrosis factor-α (TNF-α). The downstream pathway was investigated by western blot. Results: LPS induced cytotoxicity in HK-2 cell accompanied by decrease of cell viability and increase of cell apoptosis. Methyl jasmonate dosage dependently enhanced the cell viability and reduced cell apoptosis to ameliorate the cytotoxicity. LPS also induced inflammatory response in HK-2 cell with increased IL-1β, IL-6, IL-8 and TNF-α. Methyl jasmonate attenuated LPS-induced inflammation in HK-2 cell. Protein expression of IκBα was down-regulated, p65 and IκBα phosphorylation were up-regulated in LPS-induced HK-2. Methyl jasmonate attenuated LPS-induced decrease of IκBα and increase of p65 and IκBα phosphorylation in HK-2 cell. Conclusion: Methyl jasmonate demonstrated anti-apoptotic and anti-inflammatory effects on LPS-induced HK-2 cell through suppression of NF-κB activation.

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p85α Acts as a Novel Signal Transducer for Mediation of Cellular Apoptotic Response to UV Radiation

Molecular and Cellular Biology ◽

10.1128/mcb.00657-06 ◽

2007 ◽

Vol 27 (7) ◽

pp. 2713-2731 ◽

Cited By ~ 29

Author(s):

Lun Song ◽

Jingxia Li ◽

Jianping Ye ◽

Gang Yu ◽

Jin Ding ◽

...

Keyword(s):

Signaling Pathway ◽

Uv Radiation ◽

Gene Transcription ◽

Cell Apoptosis ◽

Cellular Response ◽

Nuclear Translocation ◽

Site Directed Mutagenesis ◽

Regulatory Subunit ◽

Special Effect ◽

Tnf Α

ABSTRACT Apoptosis is an important cellular response to UV radiation (UVR), but the corresponding mechanisms remain largely unknown. Here we report that the p85α regulatory subunit of phosphatidylinositol 3-kinase (PI-3K) exerted a proapoptotic role in response to UVR through the induction of tumor necrosis factor alpha (TNF-α) gene expression. This special effect of p85α was unrelated to the PI-3K-dependent signaling pathway. Further evidence demonstrated that the inducible transcription factor NFAT3 was the major downstream target of p85α for the mediation of UVR-induced apoptosis and TNF-α gene transcription. p85α regulated UVR-induced NFAT3 activation by modulation of its nuclear translocation and DNA binding and the relevant transcriptional activities. Gel shift assays and site-directed mutagenesis allowed the identification of two regions in the TNF-α gene promoter that served as the NFAT3 recognition sequences. Chromatin immunoprecipitation assays further confirmed that the recruitment of NFAT3 to the endogenous TNF-α promoter was regulated by p85α upon UVR exposure. Finally, the knockdown of the NFAT3 level by its specific small interfering RNA decreased UVR-induced TNF-α gene transcription and cell apoptosis. The knockdown of endogenous p85α blocked NFAT activity and TNF-α gene transcription, as well as cell apoptosis. Thus, we demonstrated p85α-associated but PI-3K-independent cell death in response to UVR and identified a novel p85α/NFAT3/TNF-α signaling pathway for the mediation of cellular apoptotic responses under certain stress conditions such as UVR.

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Thalidomide inhibits UVB-induced mouse epidermal cell apoptosis by a TNF-α dependent pathway

Journal of Dermatological Science ◽

10.1016/s0923-1811(98)84322-3 ◽

1998 ◽

Vol 16 ◽

pp. S221

Author(s):

Stephen Brenneman ◽

Robert Burns ◽

Ard Vink ◽

Erika Gaines ◽

Anne Haake ◽

...

Keyword(s):

Epidermal Cell ◽

Cell Apoptosis ◽

Tnf Α ◽

Mouse Epidermal Cell ◽

Dependent Pathway

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Tubeimoside-1 Protects Against Renal Ischemia Reperfusion Injury In Vivo and In Vitro

Natural Product Communications ◽

10.1177/1934578x20977647 ◽

2020 ◽

Vol 15 (12) ◽

pp. 1934578X2097764

Author(s):

Xiaoli Yuan ◽

Jing Wang ◽

Yun Zhang

Keyword(s):

Reperfusion Injury ◽

Cell Apoptosis ◽

Renal Cell ◽

Caspase 3 ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Renal Ischemia ◽

Caspase 9 ◽

Tnf Α ◽

Renal Ischemia Reperfusion Injury

Renal ischemia reperfusion injury (RIRI) is one of the main causes of acute kidney injury. This study aimed to explore whether tubeimoside-1 (TBMS1) could protect against RIRI. RIRI mice model and hypoxia/reoxygenation (H/R)-induced NRK-52E cells were used in this study. The renal pathology was observed by hematoxylin and eosin staining to calculate the tubular injury score. The levels of serum creatinine and blood urine nitrogen were analyzed by a Hitachi model 7180 automatic analyzer. The expressions of tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin 6 (IL-6), Bax, cleaved caspase-3, cleaved caspase-9, total caspase-3, and total caspase-9 in renal tissues and NRK-52E cells were detected by western blot analysis. The levels of TNF-α, IL-1β, and IL-6 in serum and NRK-52E cells were measured by a commercial enzyme-linked immunosorbent assay kit. The renal cell apoptosis in renal tissues was analyzed by TUNEL assay, and NRK-52E cell apoptosis was detected by flow cytometry analysis. CCK-8 assay was used to analyze the viability of NRK-52E cells after the indicated treatment. As a result, the renal tissues that were seriously damaged in mice with RIRI could be alleviated by TBMS1. Therefore, 50 mg/kg TBMS1 was chosen for the animal experiment. Renal cell apoptosis was increased in renal tissues of mice with RIRI. These changes could be partially reversed by TBMS1 treatment. TBMS1 improved the viability, and reduced the inflammation and apoptosis of H/R-induced NRK-52E cells. In conclusion, TBMS1 ameliorates RIRI by promoting viability and suppressing apoptosis and inflammation of renal cells.

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S100A4 promotes the progression of lipopolysaccharide-induced acute epididymitis in mice†

Biology of Reproduction ◽

10.1093/biolre/ioaa022 ◽

2020 ◽

Vol 102 (6) ◽

pp. 1213-1224 ◽

Cited By ~ 1

Author(s):

Yingjie Wu ◽

Haoran Li ◽

Yinghe Qin

Keyword(s):

Cell Proliferation ◽

Cell Apoptosis ◽

Mrna Levels ◽

Ki 67 ◽

Tnf Α ◽

Proliferation And Apoptosis ◽

Sperm Membrane ◽

Marked Cell ◽

Acute Epididymitis

Abstract S100A4 has been suggested to be a critical regulator of tumor metastasis and is implicated in the progression of inflammation. The aim of this study is to investigate the expression and possible role of S100A4 in epididymitis. Using a mouse model of epididymitis induced by the injection of lipopolysaccharide (LPS) in the deferent duct, we found that LPS administration induced an upregulation of S100a4 transcription (P < 0.05) and a recruitment of S100A4 positive cells in the epididymal interstitium of wild type (WT) mice. Co-immunofluorescence showed that S100A4 was mainly expressed by granulocytes, CD4 lymphocytes, and macrophages. Deficiency of S100A4 reduced epididymal pathological reaction and the mRNA levels of the pro-inflammatory cytokines IL-1β and TNF-α (P < 0.01), suggesting that S100A4 promotes the progression of epididymitis. Furthermore, S100A4 deficiency alleviated the decline of sperm motility and rectified the abnormal expression of sperm membrane protein AMAD3, which suggested that in the progression of epididymitis, S100A4 aggravates the damage to sperm vitality. In addition, both Ki-67 marked cell proliferation and transferase-mediated dUTP-biotin nick end labeling detected cell apoptosis were reduced in S100a4−/− mice compared with WT mice after LPS treatment, indicating that S100A4 promotes both cell proliferation and cell apoptosis in epididymitis. Overall, these results demonstrate that S100A4 promotes the progression of LPS-induced epididymitis and facilitates a decline in sperm vitality, and its function may be related to the process of cell proliferation and apoptosis during inflammation.

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