Effect of dental chew on reducing dental plaque, dental calculus and halitosis in beagle dogs.

Periodontosis is the most common clinical disease in adult dogs, which is mainly caused by plaque accumulation and seriously endangers the oral health of dogs and even cause kidney, myocardial, and liver problems in severe cases. The aim of this study was to determine the clinical efficacy of dental chew (Cature Brushing Treats product) with mechanical and chemical properties in beagles. The dogs in the experimental group were fed with a dental chew twice a day after meals; The control group had no treatment. Dental plaque was evaluated on the 14th day and 29th day, respectively. The concentration of volatile sulfur compounds (VSC) in the breath and dental calculus were also evaluated on the 29th day. The results showed that there was no significant difference in the indexes of dental plaque on the 14th day. While they had significantly reduced accumulation of plaque (37.63%), calculus (37.61%), and VSC concentration (81.08%) compared to when receiving no chew on the 29th day.

Enhanced expression of miR-204 attenuates LPS stimulated inflammatory injury through inhibiting the Wnt/ß-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/ß-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.

miR-92b ameliorates lipoteichoic acid induced endometritis by suppressing Wnt/ß-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-1ß 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 ß-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-1ß, 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.

Uterine Tissue Metabonomics Combined with 16S rRNA Gene Sequencing To Analyze the Changes of Gut Microbiota in Mice with Endometritis and the Intervention Effect of Tau Interferon.

Endometritis is a common cow disease characterized by inflammation of endometrium, which leads to infertility or low fertility of cows and brings huge economic losses to the dairy industry. Tau interferon (IFN-τ) has many important biological functions, including an anti-inflammatory effect. The present study aimed to survey the effects of IFN-τ administration on gut microflora and body metabolism in mice with endometritis and to explore the potential relationship. The results indicated that IFN-τ obviously alleviated the damage and ultrastructural changes of mouse endometrium induced by Escherichia coli and enhanced tight junction protein's expression level. Through analysis by 16S rRNA gene sequencing, we found that IFN-τ, especially at 12 h, could regulate the composition of gut microbiota associated with Pediococcus, Staphylococcus, and Enterorhabdus in E. coli-induced mouse endometritis. Through histometabonomics, it was found that endometritis was related to 11 different metabolites and 4 potential metabolic pathways. These metabolites and metabolic pathways were major participants in metabolic pathways, cysteine and methionine metabolism, arachidonic acid metabolism, and pyrimidine metabolism. Correlation analysis of gut microbiota with uterine tissue metabolomics showed that changes in metabolic pathways might be affected by gut microbiota, such as Enterorhabdus in mouse endometritis. The above results indicated that the anti-inflammatory mechanism of IFN-τ might be reduction of the abundance of Enterorhabdus in the gut microbiota, affecting the expression level of important metabolites in uterine tissue and thus playing an anti-inflammatory role. IMPORTANCE The change in intestinal flora has been the focus of many disease studies in recent years, but the pathogenetic effect of interferon on endometritis is still unclear. The results of this study showed that IFN-τ alleviated the damage in mouse endometritis induced by E. coli and improved the endometrial tissue barrier. Its functional mechanism may be reduction of the abundance of Enterorhabdus in the intestinal microbiota, affecting the expression level of important metabolites in uterine tissue and thus playing an anti-inflammatory role.

Sanguinarine Enhances the Integrity of the Blood-Milk Barrier and Inhibits Oxidative Stress in Lipopolysaccharide-Stimulated Mastitis.

Mastitis is a common clinical disease which threatens the welfare and health of dairy cows and causes huge economic losses. Sanguinarine (SG) is a plant-derived alkaloid which has many biological functions, including antibacterial and antioxidant properties. The present study attempted to evaluate the effect of SG on lipopolysaccharide (LPS)-induced oxidative stress reactions and explore its potential mechanisms. The expression profile of SG was analyzed by network pharmacology, and it was found that differentially expressed genes were mainly involved in the Wnt signaling pathway and oxidative stress through GO and KEGG enrichment. In in vitro experiments, the dosage of SG was non-toxic to mouse mammary epithelial cells (mMECs) (p > 0.05). SG not only inhibited the increase in ROS induced by LPS, but also enhanced the activity of antioxidant enzymes (p < 0.05). Moreover, the results of the in vivo experiments showed that SG alleviated LPS-induced inflammatory damage of mouse mammary glands and enhanced the integrity of the blood-milk barrier (p < 0.05). Further studies suggested that SG promoted Nrf2 expression and suppressed the activation of the Wnt signaling pathway (p < 0.05). Conclusively, this study clarified the protective effect of SG on mastitis and provided evidence for new potential mechanisms. SG exerted its antioxidant function through activating Nrf2 and inhibiting the Wnt/ß-catenin pathway, repairing the blood-milk barrier.

Protective Effects of Lentinan Against Lipopolysaccharide-Induced Mastitis in Mice.

Mastitis is a worldwide production disease in dairy cows, which mainly affects milk yield, causing huge economic losses to dairy farmers. Lentinan is a kind of polysaccharide extracted from Lentinus edodes, which has no toxicity and possesses various pharmacological activities including antibacterial and immunomodulatory effects. Therefore, the anti-inflammatory function of lentinan on LPS-stimulated mastitis was carried out, and the mechanism involved was explored. In vivo, lentinan greatly reduced LPS-stimulated pathological injury, myeloperoxidase (MPO) activity, and the proinflammatory factor production (TNF-α and IL-1ß) in mice. Further study was performed to determine the activation of the Wnt/ß-catenin pathway during LPS stimulation. These results suggested that LPS-induced activation of the Wnt/ß-catenin pathway was suppressed by lentinan administration. In vitro, we observed that the mouse mammary epithelial cell (mMEC) viability was not affected by lentinan treatment. As expected, LPS increased the TNF-α and IL-1ß protein secretion and the activation of the Wnt/ß-catenin pathway that was inhibited by lentinan administration in a dose-dependent manner in mMECs. Conclusively, lentinan exerts the anti-inflammatory function in LPS-stimulated mastitis via inhibiting the activation of the Wnt/ß-catenin pathway. Thus, the results of our study also gave an insight that lentinan may serve as a potential treatment for mastitis.

Fisetin Ameliorates the Inflammation and Oxidative Stress in Lipopolysaccharide-Induced Endometritis.

PURPOSE: Fisetin is a natural flavone of polyphenol, which widely exists in many fruits and vegetables and has many pharmacological activities. However, the mechanism involved remains largely unknown. Here, we investigate the mechanisms of fisetin on the inflammatory response and oxidative stress in LPS-induced endometritis model and bovine endometrial epithelial cell line (BEND). METHODS: The function of fisetin was analyzed by network pharmacology. Effects of increasing doses of fisetin on inflammation and oxidative stress are studied in BALB/c mice with LPS-induced endometritis. The underlying mechanisms of antioxidant activity of fisetin were further explored in LPS-stimulated BEND cells. RESULTS: The results showed that fisetin significantly alleviated LPS-induced inflammatory injury and oxidative stress both in vivo and in vitro. Further studies found that fisetin greatly inhibited the LPS stimulated TLR4 expression and nuclear translocation of nuclear factor-κB (NF-κB), thus reducing the pro-inflammatory mediators secretion. Silencing TLR4 reduced LPS-induced inflammatory responses. Moreover, we observed that fisetin evidently decreased ROS production but activated Nrf2/HO-1 pathway in LPS-stimulated BEND cells. To further explore the role of Nrf2 in fisetin-induced HO-1 protein expression, the specific siRNA was used to silence Nrf2 expression. Silencing Nrf2 abrogated the inhibitory effects of fisetin on LPS-induced pro-inflammatory cytokines TNF-α, IL-1ß secretion, NADPH oxidase-4 (Nox4) and ROS production. CONCLUSION: In conclusion, fisetin effectively protected against LPS-induced oxidative stress and inflammatory responses which may be closely correlated to inhibition of TLR4-mediated ROS/NF-κB and activation of the Nrf2/HO-1 pathway.

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-1ß 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.

miR-148a suppresses inflammation in lipopolysaccharide-induced endometritis.

Endometritis is a postnatal reproductive disorder disease, which leads to great economic losses for the modern dairy industry. Emerging evidence indicates that microRNAs (miRNAs) play a pivotal role in a variety of diseases and have been identified as critical regulators of the innate immune response. Recent miRNome profile analysis revealed an altered expression level of miR-148a in cows with endometritis. Therefore, the present study aims to investigate the regulatory role of miR-148a in the innate immune response involved in endometritis and estimate its potential therapeutic value. Here, we found that miR-148a expression in lipopolysaccharide (LPS)-stimulated endometrial epithelial cells was significantly decreased. Our results also showed that overexpression of miR-148a using agomiR markedly reduced the production of pro-inflammatory cytokines, such as IL-1ß and TNF-α. Moreover, overexpression of miR-148a also suppressed NF-κB p65 activation by targeting the TLR4-mediated pathway. Subsequently, we further verified that miR-148a repressed TLR4 expression by binding to the 3'-UTR of TLR4 mRNA. Additionally, an experimental mouse endometritis model was employed to evaluate the therapeutic value of miR-148a. In vivo studies suggested that up-regulation of miR-148a alleviated the inflammatory conditions in the uterus as evidenced by H&E staining, qPCR and Western blot assays, while inhibition of miR-148a had inverse effects. Collectively, pharmacologic stabilization of miR-148a represents a novel therapy for endometritis and other inflammation-related diseases.

Peripheral Circulating Exosome-Mediated Delivery of miR-155 as a Novel Mechanism for Acute Lung Inflammation.

Emerging evidence has revealed that excessive activation of macrophages may result in an adverse lung inflammation involved in sepsis-related acute lung injury (ALI). However, it has never been clearly identified whether peripheral circulating serum exosomes participate in the pathogenesis of sepsis-related ALI. Therefore, the purposes of our study were to investigate the effect of serum exosomes on macrophage activation and elucidate a novel mechanism underlying sepsis-related ALI. Here we found that exosomes were abundant in the peripheral blood from ALI mice and selectively loaded microRNAs (miRNAs), such as miR-155. In vivo experiments revealed that intravenous injection of serum exosomes harvested from ALI mice, but not control mice, increased the number of M1 macrophages in the lung, and it caused lung inflammation in naive mice. In vitro, we demonstrated that serum exosomes from ALI mice delivered miR-155 to macrophages, stimulated nuclear factor κB (NF-κB) activation, and induced the production of tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6. Furthermore, we also showed that serum exosome-derived miR-155 promoted macrophage proliferation and inflammation by targeting SHIP1 and SOCS1, respectively. Collectively, our data suggest the important role of circulating exosomes secreted into peripheral blood as a key mediator of septic lung injury via exosome-shuttling miR-155.

Ginsenoside Rb1 ameliorates Staphylococcus aureus-induced Acute Lung Injury through attenuating NF-κB and MAPK activation.

Acute lung injury (ALI) is clinically characterized by excessive inflammation leading to acute respiratory distress syndrome (ARDS), having high morbidity and mortality both in human and animals. Ginsenoside Rb1 (Rb1) is a major primary bioactive component extracted by Panax ginseng, which has numerous pharmacological functions such as anti-cancer, anti-inflammatory, and antioxidant. However, the anti-inflammatory effects of Rb1 in Staphylococcus aureus (S. aureus)-induced ALI in mice have not been investigated. The aim of the current study was to determine the anti-inflammatory influence of Rb1 on S. aureus-induced ALI in mice, and to explore its possible underlying principle mechanisms in RAW 264.7 macrophage cells. The results of physical morphology, histopathological variation and wet-to-dry weight ratio of lungs revealed that Rb1 significantly attenuated S. aureus-induced lung injury. Furthermore, qPCR results displayed that Rb1 inhibited IL-1ß, IL-6 and TNF-α production both in vivo and in vitro. The activation of Toll-like receptor 2 (TLR2) by S. aureus was inhibited by application of Rb1 as confirmed by results of immunofluorescence assay. The expression of NF-kB and MAPK signaling proteins revealed that Rb1 significantly attenuated the phosphorylation of p65, ERK, as well as JNK. Altogether, the results of this experiment presented that Rb1 has ability to protect S. aureus-induced ALI in mice by attenuating TLR-2-mediated NF-kB and MAPK signaling pathways. Consequently, Rb-1 might be a potential medicine in the treatment of S. aureus-induced lung inflammation.

Mycobacterium marinum down-regulates miR-148a in macrophages in an EsxA-dependent manner.

As a key virulence factor of Mycobacterium tuberculosis, EsxA is not only involved in phagosome rupture, but also functions in stimulation of immune responses in macrophages. Here, we report thatmiR-148a is down-regulated in the macrophages infected with Mycobacterium marinum (Mm). Using the knockout strain Mm∆EsxA/B, recombinant EsxA, EsxB and EsxA/B heterodimer proteins, we provide evidence that down-regulation of miR-148ais dependent on EsxA, and up-regulation of miR-148a reduces Mm intracellular survival. Moreover, up-regulation of miR-148a down-regulates the pro-inflammatory cytokines (e.g. TNF-α and IL-1ß) and the TLR4-mediated NF-κB activation. Together, miR-148a may function as an anti-inflammation modulator in responses to mycobacterial infection. Regulation of miR-148a may provide a novel venue in development of therapies in tuberculosis.

Targeting the ROS/PI3K/AKT/HIF-1α/HK2 axis of breast cancer cells: Combined administration of Polydatin and 2-Deoxy-d-glucose.

It is well established that cancer cells depend upon aerobic glycolysis to provide the energy they need to survive and proliferate. However, anti-glycolytic agents have yielded few positive results in human patients, in part due to dose-limiting side effects. Here, we discovered the unexpected anti-cancer efficacy of Polydatin (PD) combined with 2-deoxy-D-glucose (2-DG), which is a compound that inhibits glycolysis. We demonstrated in two breast cell lines (MCF-7 and 4T1) that combination treatment with PD and 2-DG induced cell apoptosis and inhibited cell proliferation, migration and invasion. Furthermore, we determined the mechanism of PD in synergy with 2-DG, which decreased the intracellular reactive oxygen (ROS) levels and suppressed the PI3K/AKT pathway. In addition, the combined treatment inhibited the glycolytic phenotype through reducing the expression of HK2. HK2 deletion in breast cancer cells thus improved the anti-cancer activity of 2-DG. The combination treatment also resulted in significant tumour regression in the absence of significant morphologic changes in the heart, liver or kidney in vivo. In summary, our study demonstrates that PD synergised with 2-DG to enhance its anti-cancer efficacy by inhibiting the ROS/PI3K/AKT/HIF-1α/HK2 signalling axis, providing a potential anti-cancer strategy.

Matrine alleviates Staphylococcus aureus lipoteichoic acid-induced endometritis via suppression of TLR2-mediated NF-κB activation.

Endometritis is one of the main diseases that causes great economic losses in the dairy industry. Recent studies have shown that matrine extracted from the traditional Chinese herb Sophora flavescens is an alkaloid with a broad range of bioactivities. Here, we aimed to investigate the protective effects of matrine on Staphylococcus aureus lipoteichoic acid (LTA)-induced endometritis in mice and elucidate the possible molecular mechanisms in vitro. Histopathological changes showed that matrine remarkably attenuated the uterus injury in a mouse model of LTA-induced endometritis. qPCR and ELISA results showed that matrine dose-dependently reduced the expression of pro-inflammatory cytokines (TNF-α and IL-1ß). To further elucidate the underlying mechanisms of this protective effect of matrine, LTA-stimulated bovine endometrial epithelial cells (bEECs) were employed in this study. The results demonstrated that TLR2 expression and its downstream nuclear factor (NF)-κB activation were both suppressed by matrine treatment. Furthermore, a small interference RNA targeting TLR2 gene mimicked matrine in its inhibition on LTA-induced activation of TLR2 and NF-κB. In conclusion, these findings suggest the protective effect of matrine against LTA-induced endometritis through negative regulation of TLR2-mediated NF-κB pathway.

MiRNA profiling of plasma-derived exosomes from dairy cows during gestation.

Exosomes, one kind of extracellular vesicles, are released under abnormal and normal physiological conditions. An understanding of plasma-derived exosomal microRNA (miRNA) profiles during pregnancy will significantly contribute to knowledge of maternal-fetal communication in ruminants. In this study, we isolated plasma-derived exosomes from dairy cows during early (∼60 days, gestational day (G_D) 60), mid (∼150 days, G_D 150) and late (∼240 days, G_D 240) pregnancy. Exosomal miRNA profiles were revealed using RNA sequencing technology, and the abundance of exosomal miRNAs between each stage were compared. In the G_D150 vs. G_D60, G_D240 vs. G_D60 and G_D240 vs. G_D150stages, there were 23, 32 and 29 miRNAs, respectively, significantly differentially enriched. Significant annotations for protein binding and transport- or immunoregulatory-related categories or pathways were found for the predicted target genes of these miRNAs. In addition, we further identified specific exosomal miRNAs for each pregnancy stage, including the following: bta-miR-499, bta-miR-16a, bta-miR-20a, bta-miR-223, and bta-miR-128 in the G_D60 stage; bta-miR-493, bta-miR-127, and bta-miR-143 in the G_D150 stage; and bta-miR-122, bta-miR-182, bta-miR-183, bta-miR-200b, and bta-miR-200c in the G_D240 stage. Our findings provide new insight into maternal-fetal communication during pregnancy. Future studies will use these data to identify and characterize specific exosomal miRNA regulatory mechanisms in the maternal-fetal immune response.

Sodium houttuyfonate inhibits LPS­induced mastitis in mice via the NF­κB signalling pathway.

Sodium houttuyfonate (SH) has been indicated to play an important anti­inflammatory role. Previous studies have confirmed that SH can inhibit the NF­κB pathway in lipopolysaccharide (LPS)­induced mastitis in bovine mammary epithelial cells. However, the effects of SH on LPS­induced mastitis in animals should be verified to further evaluate its actual value. In the present study, the anti­inflammatory effects of SH were investigated in mouse models and a mouse mammary epithelial cell line. Hematoxylin and eosin staining (H&E) showed that SH therapy significantly alleviated the pathological changes in mammary glands. Myeloperoxidase (MPO) activity analysis demonstrated that SH substantially decreased MPO activity in vivo. RT­qPCR results showed that SH reduced the expression of interleukin (IL)­1, IL­6 and tumor necrosis factor α both in vivo and in vitro. In addition, western blot results indicated that SH suppressed the phosphorylation of nuclear factor kappa­light­chain­enhancer of activated B­cells (NF­κB) p65 protein and reduced the degradation of inhibitor of kappa light polypeptide gene enhancer in B­cells alpha protein in vivo and in vitro. These results demonstrated that SH ameliorates LPS­induced mastitis by inhibiting the NF­κB pathway.

Sodium selenite induces apoptosis via ROS-mediated NF-κB signaling and activation of the Bax-caspase-9-caspase-3 axis in 4T1 cells.

Sodium selenite (SSE), a source of inorganic selenium, has been widely used as a clinical cancer treatment, but the precise molecular mechanisms of SSE remain to be elucidated. Our in vitro experiments have confirmed that SSE treatment causes a transient increase in intracellular reactive oxygen species (ROS) levels, resulting in the inhibition of nuclear transcription factor-κB (NF-κB) signaling and p65 and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha phosphorylation levels in 4T1 cells. The inhibition of NF-κB subsequently increased the expression of the apoptosis gene B-cell lymphoma-2-associated X (Bax) and downregulated the transcription of antiapoptosis genes, such as B-cell lymphoma-2, cellular inhibitor of apoptosis 1, and X-linked inhibitor of apoptosis. Additionally, the accumulation of ROS caused mitochondrial dysfunction, leading to the activation of caspase-9 and -3, thereby resulting in apoptosis. However, modulation of the ROS level by the chemical inhibitor N-acetyl-cysteine reversed these events. Similarly, in vitro murine syngeneic breast tumor models showed that SSE inhibits tumor growth by promoting apoptosis. These results indicate that SSE induces apoptosis via ROS-mediated inhibition of NF-κB signaling and activation of the Bax-caspase-9-caspase-3 axis.

MicroRNA let-7c Improves LPS-Induced Outcomes of Endometritis by Suppressing NF-κB Signaling.

Endometritis is a common inflammatory disease which endangers human and animal reproductive health. MicroRNA (miRNA) let-7c plays an important role in the inflammatory process; however, the regulatory underlying mechanism of let-7c in endometritis is unclear. In this study, we confirmed that let-7c was significantly reduced in LPS-induced mouse endometritis model, and overexpression of let-7c was able to effectively reduce uterine tissue damage caused by lipopolysaccharide (LPS), and then, a LPS-induced bovine endometrial epithelial cell (BEND) line was used to mimic the inflammatory model in vitro. Our data showed that overexpression of let-7c significantly reduced the expression of pro-inflammatory cytokines in BEND cells induced by LPS. Meanwhile, immunofluorescence and western blotting results showed that let-7c significantly inhibited LPS-induced phosphorylation of NF-κB, thereby inhibiting downstream pro-inflammatory cytokine expression. Taken together, our results suggested that let-7c ameliorates LPS-induced endometritis by attenuating the expression of pro-inflammatory cytokines via inhibition of the activation of NF-κB.

Methylseleninic Acid Suppresses Breast Cancer Growth via the JAK2/STAT3 Pathway.

Previous studies show that methylseleninic acid (MSA), which is the most common selenium derivative used as a drug in humans, exerts specific cytotoxic effects in several cancer cell types. However, the complex mechanism of these effects has not been fully elucidated. Here, we demonstrate by Cell Counting Kit-8 in mouse breast cancer cell line 4T1 that MSA inhibits cell viability in a concentration-dependent (5, 10, 20 µmol/L) and time-dependent (6, 12, 24 hours) manner. Flow cytometry, Western blot, and Reverse Transcription-Polymerase Chain Reaction (RT-PCR) analyses indicated that MSA inhibits cancer cell invasion and induces apoptosis by the activation of caspase-3, poly ADP ribose polymerase 1 (PARP1), and BCL2-associated X. Furthermore, MSA demonstrated anticancer activity by inhibiting the Janus kinase 2/signal transducers and activators of transcription 3 (JAK2/STAT3) pathway. The MSA treatment for 24 hours decreased the phosphorylation of JAK2 and STAT3 in 4T1 cells by Western blot. We also confirmed this with the use of a JAK2 chemical inhibitor, AG490, as a positive control. In a 4T1 orthotopic allograft model, morphological and TdT-mediated dUTP nick-end labeling analyses showed that MSA treatment (1.5 mg/kg/weight) for 28 days inhibits tumor growth consistent with the clinical anticancer drug cyclophosphamide. Our observations demonstrate that MSA is a potent anticancer drug in breast cancer and uncovered a key role of the JAK2/STAT3 pathway in modulating tumor growth.