Enforced expression of miR-92b blunts E. coli lipopolysaccharide-mediated inflammatory injury by activating the PI3K/AKT/β-catenin pathway via targeting PTEN

Up-regulation of inflammatory, oxidative stress, and apoptotic mediators via inflammatory, oxidative stress, and apoptosis-associated pathways in bovine endometritis

Endometritis is the inflammation of the endothelial lining of the uterine lumen and is multifactorial in etiology. Escherichia (E.) coli is a Gram-negative bacteria, generally considered as a primary causative agent for bovine endometritis. Bovine endometritis is characterized by the activation of Toll-like receptors (TLRs) by E. coli, which in turn triggers inflammation, oxidative stress, and apoptosis. The objective of this study was to investigate the gene expression of inflammatory, oxidative stress, and apoptotic markers related to endometritis in the uteri of cows. Twenty uterine tissues were collected from the abattoir. Histologically, congestion, edema, hyperemia, and hemorrhagic lesions with massive infiltration of neutrophil and cell necrosis were detected markedly (P < 0.05) in infected uterine samples. Additionally, we identify E. coli using the ybbW gene (177 base pairs; E. coli-specific gene) from infected uterine samples. Moreover, qPCR and western blot results indicated that TLR2, TLR4, proinflammatory mediators, and apoptosis-mediated genes upregulated except Bcl-2, which is antiapoptotic, and there were downregulations of oxidative stress-related genes in the infected uterine tissue. The results of our study suggested that different gene expression regimes related to the immune system reflex were activated in infected uteri. This research gives a novel understanding of active immunological response in bovine endometritis.

Regulation of inflammatory response by LINC00346 via miR-25-3p-mediated modulation of the PTEN/PI3K/AKT/NF-κB pathway

Long intergenic non-coding RNA 346 (LINC00346) has been reported to be involved in the development of atherosclerosis and specific cancers by affecting signaling pathways. However, its function in inflammation has not been thoroughly studied. Therefore, its expression pattern and function were determined in the human macrophage-like cell line THP-1. Lipopolysaccharide (LPS) treatment induced the expression of LINC00346. LPS-induced NF-κB activation and proinflammatory cytokine expression were suppressed or enhanced by the overexpression or knockdown of LINC00346, respectively. Analyses using dual luciferase assay and decoy RNAs that could block RNA-RNA interactions indicated that LINC00346 improves phosphatase and tensin homolog (PTEN) expression by sponging miR-25-3p. Subsequently, PTEN suppresses phosphoinositide-3 kinase (PI3K)-mediated conversion of phosphatidylinositol-4,5-bisphosphate (PIP2) into phosphatidylinositol-3,4,5-trisphosphate (PIP3) as well as consequent activation of protein kinase B (AKT) and NF-κB. Interestingly, database analysis revealed that the expression levels of LINC00346 and PTEN were simultaneously decreased in breast cancer tissues. Further analyses conducted using a breast cancer cell line, MDA-MB-231, confirmed the functional relationship among LINC00346, miR-25-3p, and PTEN in LPS-induced activation of NF-κB. These results indicate that miR-25-3p-sponging activity of LINC00346 affects the balance between PTEN and PI3K as well as the downstream activation of AKT/NF-κB pathway in inflammatory conditions.

miR-92b ameliorates lipoteichoic acid induced endometritis by suppressing Wnt/β-catenin pathway activation

Endometritis is one of the important reasons for the low fecundity of dairy cows, which has brought huge economic losses to the dairy industry. Emerging evidence suggests that miR-92b is a novel therapeutic molecule that plays a crucial role in many inflammatory diseases. However, its mechanism in lipoteichoic acid (LTA) induced endometritis remains unclear. In the present study, we explored the mechanism of miR-92b on LTA-induced endometritis in vivo and in vitro. The result displayed that the expression of miR-92b was reduced in LTA induced mouse endometritis and bovine endometrial epithelial cell lines (BEND). Overexpression miR-92b significantly alleviated mouse uterine injury and reduced the protein levels of TNF-α, IL-1β and the MPO activity. The reporter assay of luciferase showed that miR-92b directly targeted the transmembrane receptor Frizzled-10 (FZD10), a transmembrane-type Wnt receptor. Molecular experiments were further performed to explore the mechanism of miR-92b in protecting LTA induced endometritis. The results of in vitro suggested that miR-92b mimic decreased the protein levels of Wnt3a and β-catenin in LTA stimulated BEND, which were abolished by overexpression of FZD10. As expected, miR-92b mimic decreased the expression levels of TNF-α and IL-1β, while overexpression of FZD10 promoted the production of these pro-inflammatory cytokines. Collectively, the above findings indicated that miR-92b might be an effective strategy for treatment of LTA induced endometritis.

Enhanced expression of miR-204 attenuates LPS stimulated inflammatory injury through inhibiting the Wnt/β-catenin pathway via targeting CCND2

One of the most common bacterial diseases of the reproductive system in dairy cows is endometritis, which will cause huge economic loss. Here, we investigate the mechanisms of miR-204 on LPS-stimulated endometritis in vitro and in vivo. Experiments displayed that the expression of miR-204 was lower in bovine uterine tissue samples or bovine endometrial epithelial cell line (BEND) that stimulated by LPS. Compared with the negative group, miR-204 treatment significantly suppressed the production of proinflammatory factors and the Wnt/β-catenin pathway activation. Additionally, the result of the dual luciferase assay showed that miR-204 targeted cyclin D2. More importantly, up-regulation of miR-204 alleviated LPS induced uterine injury was confirmed in vivo studies. Molecular experiments indicated that the expression level of tight junctional proteins Claudin3 and cadherin1 were both enchanced by miR-204 treatment. Accordingly, miR-204 may serve as a new measure to prevent and treat endometritis caused by LPS.

Interferon-tau protects bovine endometrial epithelial cells against inflammatory injury by regulating the PI3K/AKT/β-catenin/FoxO1 signaling axis

Endometritis is one of the most common causes of infertility in dairy cows, and is histopathologically characterized by inflammation and damage of endometrial epithelium. Interferon-tau (IFN-τ) is a novel type I interferon secreted by ruminant trophoblast cells with low cytotoxicity even at high doses. Previous studies suggested that IFN-τ plays an important role in inflammation. However, the mechanisms whereby IFN-τ may modulate the inflammatory responses in the bovine endometrium are unknown. In the present study, primary bovine endometrial epithelial cells (BEEC) isolated from fresh and healthy uterine horns were used for in vitro studies. The integrity of BEEC was assessed by immunofluorescence staining for cytokeratin 18 (CK-18, a known epithelial marker). For the experiments, BEEC were stimulated with different concentrations of lipopolysaccharide (LPS; 0-20 µg/mL) for different times (0-24 h). Cell viability and apoptosis were assessed via CCK-8 and flow cytometry. In a preliminary study, we observed that compared with the control group without LPS, 10 µg/mL of LPS stimulation for 24 h induced apoptosis. In a subsequent study, 20 or 40 ng/mL of IFN-τ alleviated LPS-induced apoptosis. Relative to the LPS group, western blotting further revealed that IFN-τ inhibited the protein abundance of TLR4 and phosphorylated (p-) p65 (p-p65) and Bax/Bcl-2 ratio, suggesting that IFN-τ can protect BEEC against inflammatory injury. Furthermore, the protein abundance of p-phosphoinositide 3-kinase (p-PI3K), p-protein kinase B (p-AKT), p-glycogen synthase kinase-3β (p-GSK3β), β-catenin, and p-forkhead box O1 (p-FoxO1) was lower in the LPS group, whereas IFN-τ upregulated their abundance. The use of LY294002, a specific inhibitor of PI3K/AKT, attenuated the upregulation of p-PI3K, p-AKT p-GSK3β, β-catenin, and p-FoxO1 induced by IFN-τ, and also blocked the downregulation of TLR4, p-p65, and Bax/Bcl-2 ratio. This suggested that the inhibition of TLR4 signaling by IFN-τ was mediated by the PI3K/AKT pathway. Furthermore, compared with the LPS group, the β-catenin agonist SB216763 led to greater p-FoxO1 and lower p-p65 and cell apoptosis. In contrast, knockdown of β-catenin using small interfering RNA had the opposite effects. To explore the role of FoxO1 on the inhibition of TLR4 by IFN-τ, we employed LY294002 to inhibit the PI3K/AKT while FoxO1 was knocked down. Results revealed that the knockdown of FoxO1 blocked the upregulation of TLR4 and p-p65 induced by LY294002, and enhanced the inhibition of IFN-τ on TLR4, p-p65, and cell apoptosis. Overall, these findings confirmed that IFN-τ can protect endometrial epithelial cells against inflammatory injury via suppressing TLR4 activation through the regulation of the PI3K/AKT/β-catenin/FoxO1 axis. These represent new insights into the molecular mechanisms underlying the anti-inflammatory function of IFN-τ in BEEC, and also provide a theoretical basis for further studies on the in vivo application of IFN-τ to help prevent negative effects of endometritis.

MiR-495-3p attenuates cell pyroptosis and endometritis through inhibiting the activation of NLRP3 inflammasome in bovine

miR-495 is aberrantly expressed and affects the progression of inflammation in various diseases. However, the mechanisms of miR-495 in bovine endometritis remain largely unknown. This study investigated the mechanism of miR-495 in lipopolysaccharide (LPS)-induced bovine endometritis and pyroptosis and found that miR-495 inhibits NLRP3 inflammasome activation and inflammatory immune responses in endometritis tissue and cell models. Bovine endometrial epithelial cells (BENDs) were treated with 10 μg/mL LPS to establish a cell inflammatory model. LPS stimulation activated the NLRP3 inflammasome and elevated the expression of proinflammatory factors in BEND cells. In addition, pyroptosis and methylation-dependent inhibition of miR-495 was discovered in LPS-exposed BENDs. Furthermore, overexpression of miR-495 inhibited activation of the NLRP3 inflammasome in vitro and vivo. Collectively, our data demonstrate that miR-495 can attenuate activation of the NLRP3 inflammasome to protect against pyroptosis and bovine endometritis, which provides novel therapeutic targets for bovine endometritis and other inflammatory diseases.

Melatonin Alleviates Lipopolysaccharide-Induced Endometritis by Inhibiting the Activation of NLRP3 Inflammasome through Autophagy

Bovine endometritis is characterized by reduced milk production and high rates of infertility. Prior research has indicated that melatonin may possess anti-inflammatory and antioxidant properties that can counteract the progression of inflammatory diseases. In this research, we attempted to elucidate the protective effects of melatonin on LPS-induced endometritis. The results obtained from enzyme-linked immunosorbent assay (ELISA) and quantitative real-time PCR (qRT-PCR) revealed that melatonin effectively reduced the production and release of pro-inflammatory cytokines in an LPS-induced bovine endometrial epithelial cell line (BEND cells). Furthermore, western blotting demonstrated that melatonin treatment reduced the expression levels of the NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome-related proteins, including NLRP3, activated caspase-1, and cleaved IL-1β. Importantly, we further demonstrated that the anti-inflammatory effect of melatonin on BEND cells was related to autophagy by western blotting. Moreover, we used western blotting to detect autophagy-related proteins, MitoSOX to detect mitochondrial reactive oxygen species production (mtROS), and mitochondrial membrane potential (MMP) assay to detect mitochondrial membrane potential. The administration of melatonin demonstrated a significant enhancement in autophagy within BEND cells, leading to the effective elimination of impaired mitochondria. This process resulted in a reduction in the generation of reactive oxygen species within the mitochondria, restoration of mitochondrial membrane potential, and inhibition of the NLRP3 inflammasome activation. Moreover, in a mouse model of LPS-induced endometritis, melatonin treatment repressed the expression of pro-inflammatory cytokines by ELISA and qRT-PCR, alleviated pathological changes by hematoxylin-eosin staining (H&E), and inhibited myeloperoxidase (MPO) activity. In conclusion, our study showed that melatonin inhibited the activation of the NLRP3 inflammasome in BEND cells through autophagy, which may provide a novel therapeutic strategy for bovine endometritis.

miRNA expression profiles of peripheral white blood cells from beef heifers with varying reproductive potential

Reproductive performance is the most critical factor affecting production efficiency in the cow-calf industry. Heifers with low reproductive efficiency may fail to become pregnant during the breeding season or maintain a pregnancy. The cause of reproductive failure often remains unknown, and the non-pregnant heifers are not identified until several weeks after the breeding season. Therefore, improving heifer fertility utilizing genomic information has become increasingly important. One approach is using microRNAs (miRNA) in the maternal blood that play an important role in regulating the target genes underlying pregnancy success and thereby in selecting reproductively efficient heifers. Therefore, the current study hypothesized that miRNA expression profiles from peripheral white blood cells (PWBC) at weaning could predict the future reproductive outcome of beef heifers. To this end, we measured the miRNA profiles using small RNA-sequencing in Angus-Simmental crossbred heifers sampled at weaning and retrospectively classified as fertile (FH, n = 7) or subfertile (SFH, n = 7). In addition to differentially expressed miRNAs (DEMIs), their target genes were predicted from TargetScan. The PWBC gene expression from the same heifers were retrieved and co-expression networks were constructed between DEMIs and their target genes. We identified 16 differentially expressed miRNAs between the groups (p-value ≤0.05 and absolute (log2 fold change ≥0.05)). Interestingly, based on a strong negative correlation identified from miRNA-gene network analysis with PCIT (partial correlation and information theory), we identified miRNA-target genes in the SFH group. Additionally, TargetScan predictions and differential expression analysis identified bta-miR-1839 with ESR1 , bta-miR-92b with KLF4 and KAT2B, bta-miR-2419-5p with LILRA4, bta-miR-1260b with UBE2E1, SKAP2 and CLEC4D, and bta-let-7a-5p with GATM, MXD1 as miRNA-gene targets. The miRNA-target gene pairs in the FH group are over-represented for MAPK, ErbB, HIF-1, FoxO, p53, mTOR, T-cell receptor, insulin and GnRH signaling pathways, while those in the SFH group include cell cycle, p53 signaling pathway and apoptosis. Some miRNAs, miRNA-target genes and regulated pathways identified in this study have a potential role in fertility; other targets are identified as novel and need to be validated in a bigger cohort that could help to predict the future reproductive outcomes of beef heifers.

miR-92b-5p negatively regulates IKK through targeting its ORF region in the innate immune responses of amphioxus (Branchiostoma belcheri)

Cephalochordate (Amphioxus), situated at a key phylogenetic position in the phylum Chordata, serves as a model organism for studying the origin and evolution of the vertebrate innate immune. In this study, five members of precursor miR-92 family (miR-92a-1, miR-92a-2, miR-92b, miR-92c and miR-92d) are identified in Branchiostoma belcheri, and their evolutionary conservation and potential molecular functions in innate immunity are analyzed. Among them, miR-92b-5p was validated in HEK293 cells to target the coding region but not classic 3'UTR of IKK (inhibitor of nuclear factor kappa-B kinase) mRNA, one integral component of MAPK and TLR4 immune signaling. Furthermore, the spatiotemporal expression patterns of miR-92b-5p and IKK were examined in different tissues or different time points (2 h, 4 h, 8 h, 12 h, 24 h and 48 h) post LPS stimulation at RNA and protein level in vivo. The seemingly inverse expression pattern between miR-92b-5p and IKK supports the involvement of miR-92b-5p in Branchiostoma belcheri innate immune response. In conclusion, our work not only illustrates the evolutionary pattern of Branchiostoma belcheri miR-92 family across chordates, but also reveals that miR-92b-5p could target IKK expression to regulate innate immune response.

Berberine enhances autophagic flux by activating the Nrf2 signaling pathway in bovine endometrial epithelial cells to resist LPS-induced apoptosis

Berberine exerts many beneficial effects on lipopolysaccharide (LPS)-induced bovine endometrial epithelial cells (BEECs). Recently, we also found that berberine shows significant antiapoptotic and autophagy-promoting activities, but the underlying mechanism has not been elucidated. This research explored the association between the antiapoptotic and autophagy-promoting activities of berberine in LPS-treated BEECs. BEECs were first preconditioned with an inhibitor of autophagic flux (chloroquine [CQ]) for 1 h, treated with berberine for 2 h, and then incubated with LPS for 3 h. Cell apoptosis was assessed by flow cytometry, and autophagy activities were assessed by immunoblot analysis of LC3II and p62. The results indicated that the antiapoptotic activity of berberine was notably inhibited in LPS-treated BEECs after preconditioning with CQ for 1 h. Furthermore, to determine whether berberine promoted autophagy by activating the nuclear factor-erythroid 2 related factor 2 (Nrf2) signaling pathway, we assessed autophagy in LPS-treated BEECs after preconditioning with a signaling pathway inhibitor of Nrf2 (ML385). The results indicated that the enhanced autophagy activity induced by berberine was partially reversed in LPS-treated BEECs after the Nrf2 signaling pathway was disturbed by ML385. In conclusion, berberine enhances autophagic flux to allow resistance to LPS-induced apoptosis by activating the Nrf2 signaling pathway in BEECs. The present study may provide new insight into the antiapoptotic mechanism of berberine in LPS-induced BEECs.

WNT/β-catenin pathway and circadian rhythms in obsessive-compulsive disorder

The neuropsychiatric disease named obsessive-compulsive disorder is composed by obsessions and/or compulsions. Obsessive-compulsive disorder etiologies are undefined. However, numerous mechanisms in several localizations are implicated. Some studies showed that both glutamate, inflammatory factors and oxidative stress could have main functions in obsessive-compulsive disorder. Glycogen synthase kinase-3β, the major negative controller of the WNT/β-catenin pathway is upregulated in obsessive-compulsive disorder. In obsessive-compulsive disorder, some studies presented the actions of the different circadian clock genes. WNT/β-catenin pathway and circadian clock genes appear to be intricate. Thus, this review focuses on the interaction between circadian clock genes and the WNT/β-catenin pathway in obsessive-compulsive disorder.

Icariin Alleviates Escherichia coli Lipopolysaccharide-Mediated Endometritis in Mice by Inhibiting Inflammation and Oxidative Stress

Icariin (ICA) is a naturally occurring phytochemical agent primarily extracted from Epimedium Brevicornum Maxim (Family Berberidaceae) with a broad spectrum of bioactivities. Endometritis is a uterine disease that causes enormous losses in the dairy industry worldwide. In this study, anti-inflammatory and anti-oxidant properties of ICA were investigated against lipopolysaccharide (LPS)-induced endometritis in mice to investigate possible underlying molecular mechanisms. Sixty heathy female Kunming mice were randomly assigned to four groups (n = 15), namely control, LPS, LPS + ICA, and ICA groups. The endometritis was induced by intrauterine infusion of 50 µL of LPS (1 mg/mL). After 24 h of onset of LPS-induced endometritis, ICA groups were injected thrice by ICA intraperitoneally six hours apart. Histopathological examination, enzyme linked immunosorbent assay (ELISA), real time quantitative polymerase chain reaction (RT-qPCR), western blotting, and immunohistochemistry were used in this study. Histological alterations revealed that ICA markedly mitigated uterine tissue injury caused by LPS. The results showed that the ICA inhibited the production of pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α) and boosted the production of anti-inflammatory cytokines (IL-10). Additionally, ICA modulated the expression of malondialdehyde (MDA), reactive oxygen species (ROS), superoxide dismutase 1 (SOD1), catalase (CAT), and glutathione peroxidase 1 (Gpx1) induced by LPS. The administration of ICA significantly (p < 0.05) improved the mRNA and protein expression of Toll-like receptor (TLR) 4. The western blotting and ELISA finding revealed that the ICA repressed LPS-triggered NF-κB pathway activation. Moreover, ICA improved the antioxidant defense system via activation of the Nrf2 pathway. The results revealed that ICA up-regulated the mRNA and protein expression of Nuclear erythroid-2-related factor (Nrf2), NAD(P)H: quinone oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1), and glutamate-cysteine ligase catalytic subunit (GCLC) under LPS exposure. Conclusively, our findings strongly suggested that ICA protects endometritis caused by LPS by suppressing TLR4-associated NF-κB and Nrf2 pathways. Altogether, these innovative findings may pave the way for future studies into the therapeutic application of ICA to protect humans and animals against endometritis.

Astragalus polysaccharides and astragaloside IV alleviate inflammation in bovine mammary epithelial cells by regulating Wnt/β-catenin signaling pathway

The Wnt/β-catenin signaling regulates cell renewal and repair and is closely associated with inflammation. Astragalus polysaccharides (APS) and astragaloside IV (AS-IV), which are the main active substances extracted from Radix Astragali, protect cells by regulating Wnt signaling in cells, exerting antiinflammatory, antioxidant, and antistress effects. However, the mechanisms by which APS and AS-IV interact with Wnt signaling to achieve their therapeutic effects in bovine mammary epithelial cells (BMECs) are not understood. In this study, we used lipopolysaccharide (LPS)-stimulated BMECs as an in vitro model of inflammation to investigate the effects of APS and AS-IV on Wnt signaling in inflamed BMECs. Drug concentrations were screened using the CCK-8 method, the effect on protein expression was analyzed using immunoblotting, the effect on inflammatory factors using enzyme-linked immunosorbent assay, and the effect on oxidative factors using enzyme labeling and flow cytometry. LPS activated the expression of inflammatory and oxidative factors in cells and inhibited Wnt/β-catenin signaling. APS and AS-IV antagonized the inhibitory effect of LPS, protecting BMECs. They inhibited the expression of the IL-6, IL-8, and TNF-α inflammatory factors, and that of the MDA oxidative factor, and activated Wnt signaling in LPS-stimulated BMECs. Silencing of β-catenin abolished the protective effect of APS and AS-IV against LPS-stimulated BMECs. Thus, APS and AS-IV mediate protective effects in inflammatory BMECs model through activation of the Wnt signaling pathway. Wnt signaling pathway is one of the targets of the inhibitory effects of APS and AS-IV on inflammation.

Synovial mesenchymal stem cell-derived extracellular vesicles alleviate chondrocyte damage during osteoarthritis through microRNA-130b-3p-mediated inhibition of the LRP12/AKT/β-catenin axis

BACKGROUND

Synovial mesenchymal stem cells (SMSCs) have been discussed as promising tools for protecting chondrocytes from loss and inhibiting osteoarthritis (OA). This work infocuses on the function of SMSC-derived extracellular vesicles (EVs) in chondrocytes during OA and the molecular mechanism.

METHODS

EVs were extracted from SMSCs and identified. Chondrocytes were treated with interleukin (IL)-1β to induce an OA-like condition in vitro and then treated with EVs. The proliferation, apoptosis, migration, extracellular matrix (ECM) degradation and inflammation in chondrocytes were examined. Key microRNAs (miRNAs) carried by EVs were screened using a microarray analysis, and the downstream molecules involved were explored using bioinformatic analysis. Rescue experiments were performed to validate the involvements of these molecules in EV-mediated events.

RESULTS

EVs restored proliferation and migration while reduced apoptosis, ECM degradation and the secretion of pro-inflammatory cytokines in chondrocytes induced by IL-1β. miR-130b-3p was significantly elevated in chondrocytes after EVs treatment. Knockdown of miR-130b-3p blocked the protective roles of EVs against IL-1β-induced damage to chondrocytes. miR-130b-3p was found to target LDL receptor related protein 12 (LRP12) mRNA in chondrocytes. Overexpression of LRP12 counteracted the effects of EVs as well and activated the AKT/β-catenin signaling pathway.

CONCLUSION

This study provided evidence that EVs alleviate chondrocyte damage during OA through miR-130b-3p-mediated inhibition of the LRP12/AKT/β-catenin axis. This study may offer novel thoughts into the protection of chondrocytes and the management of OA.

Therapeutic Role of miR-30a in Lipoteichoic Acid-Induced Endometritis via Targeting the MyD88/Nox2/ROS Signaling

Staphylococcus aureus (S. aureus), a notorious pathogenic bacterium prevalent in the environment, causes a wide range of inflammatory diseases such as endometritis. Endometritis is an inflammatory disease in humans and mammals, which prolongs uterine involution and causes great economic losses. MiR-30a plays an importan trole in the process of inflammation; however, the regulatory role of miR-30a in endometritis is still unknown. Here, we first noticed that there was an increased level of miR-30a in uterine samples of cows with endometritis. And then, bovine endometrial epithelial (BEND) cells stimulated with the virulence factor lipoteichoic acid (LTA) from S. aureus were used as an in vitro endometritis model to explore the potential role of miR-30a in the pathogenesis of endometritis. Our data showed that the induction of the miR-30a expression is dependent on NF-κB activation, and its overexpression significantly decreased the levels of IL-1β and IL-6. Furthermore, we observed that the overexpression of miR-30a inhibited its translation by binding to 3′−UTR of MyD88 mRNA, thus preventing the activation of Nox2 and NF-κB and ROS accumulation. Meanwhile, in vivo studies further revealed that upregulation of miR-30a using chemically synthesized agomirs alleviates the inflammatory conditions in an experimental mouse model of endometritis, as indicated by inhibition of ROS and NF-κB. Taken together, these findings highlight that miR-30a can attenuate LTA-elicited oxidative stress and inflammatory responses through the MyD88/Nox2/ROS/NF-κB pathway and may aid the future development of novel therapies for inflammatory diseases caused by S. aureus, including endometritis.