STAT5-mediated transcription of miR-33-5p in Mycoplasma gallisepticum-infected DF-1 cells.

RESEARCH HIGHLIGHTS: MG-HS regulates the expression of transcription factor STAT5.Transcription factor STAT5 can target miR-33-5p promoter element.MG-influenced STAT5 regulates miR-33-5p and its target gene expression.

Low let-7d microRNA levels in chick embryos enhance innate immunity against Mycoplasma gallisepticum by suppressing the mitogen-activated protein kinase pathway.

Chick embryos are a valuable model for studying immunity and vaccines. Therefore, it is crucial to investigate the molecular mechanism of the Mycoplasma gallisepticum (MG)-induced immune response in chick embryos for the prevention and control of MG. In this study, we screened for downregulated let-7d microRNA in MG-infected chicken embryonic lungs to explore its involvement in the innate immune mechanism against MG. Here, we demonstrated that low levels of let-7d are a protective mechanism for chicken embryo primary type II pneumocytes (CP-II) in the presence of MG. Specifically, we found that depressed levels of let-7 in CP-II cells reduced the adhesion capacity of MG. This suppressive effect was achieved through the activated mitogen-activated protein kinase phosphatase 1 (MKP1) target gene and the inactivated mitogen-activated protein kinase (MAPK) pathway. Furthermore, MG-induced hyperinflammation and cell death were both alleviated by downregulation of let-7d. In conclusion, chick embryos protect themselves against MG infection through the innate immune molecule let-7d, which may result from its function as an inhibitor of the MAPK pathway to effectively mitigate MG adhesion, the inflammatory response and cell apoptosis. This study may provide new insight into the development of vaccines against MG.

Comparative Transcriptome Analysis Reveals the Innate Immune Response to Mycoplasma gallisepticum Infection in Chicken Embryos and Newly Hatched Chicks.

Mycoplasma gallisepticum (MG) is a major cause of chronic respiratory diseases in chickens, with both horizontal and vertical transmission modes and varying degrees of impact on different ages. The innate immune response is crucial in resisting MG infection. Therefore, this study aimed to investigate the innate immune response of chicken embryos and newly hatched chicks to MG infection using comparative RNA-seq analysis. We found that MG infection caused weight loss and immune damage in both chicken embryos and chicks. Transcriptome sequencing analysis revealed that infected chicken embryos had a stronger immune response than chicks, as evidenced by the higher number of differentially expressed genes associated with innate immunity and inflammation. Toll-like receptor and cytokine-mediated pathways were the primary immune response pathways in both embryos and chicks. Furthermore, TLR7 signaling may play an essential role in the innate immune response to MG infection. Overall, this study sheds light on the development of innate immunity to MG infection in chickens and can help in devising disease control strategies.

Iron-calcium reinforced solidification of arsenic alkali residue in geopolymer composite: Wide pH stabilization and its mechanism.

Arsenic-alkali residue (AAR) from antimony production can pose significant health and environmental hazards due to the risk of arsenic (As) leaching. In this study, geopolymer composite synthesized from fly ash (FA) was investigated for efficient stabilization of high-arsenic-containing AAR (As2O3 of 22.74 wt%). Two industrial wastes, e.g., granulated blast furnace slag (GBFS) with active calcium composition and water-quenched slag (WQS) from lead-zinc smelting with active iron composition, were investigated for the reinforcement of AAR geopolymer solidification. A wide pH stabilization (from pH = 3-pH = 12) of AAR with the geopolymer composite was successfully achieved, and As leaching concentration of geopolymer with the addition of 5 wt% AAR was significantly reduced from 2343.73 mg/L (AAR) to that below 0.18 mg/L, which successfully meet the regulatory limit of Chinese domestic waste landfill (GB, 18598-2019, 1.2 mg/L) and hazardous waste landfill (GB16889-2008, 0.3 mg/L). Johnbaumite (Ca5(AsO4)3(OH)) was formed in geopolymer composite and leached samples with initial pH from 2.6 to 6 (final pH from 5.54 to 13.15). Magnetite and iron hydroxide phases with strong adsorption and/or As co-precipitation capability were also observed. As stabilization was also achieved with iron oxidation from As(III) to As(V). This study solves the problem of unstable As leaching at different pH for the solidification of arsenic-bearing solid waste, and provides a promising and practical strategy for efficient solidification/stabilization of AAR as well as other similar arsenic-bearing solid wastes with geopolymer composite.

Host resistance to Mycoplasma gallisepticum infection is enhanced by inhibiting PI3K/Akt pathway in Andrographolide-treating chickens.

Mycoplasma gallisepticum (MG) is a pathogenic microorganism that causes chronic respiratory disease (CRD). MG infection has a serious negative impact on the poultry industry. Andrographolide (AG) is known to regulate immune responses, antimicrobial infections, and anti-inflammatory responses. However, the underlying molecular mechanisms of AG action in MG-infected chickens remain unclear. Hence, we constructed models of MG infection by using chickens and chicken macrophage-like (HD11) cells in vivo and in vitro, respectively. The results showed that AG significantly inhibited the mRNA and protein expression of the toxic adhesion protein pMGA1.2 in vivo and in vitro. Meanwhile, AG treatment significantly decreased the mRNA expression of pro-inflammatory such as interleukin-6 (IL-6) and interleukin- 1ß (IL-1ß), and increased the mRNA expression of an anti-inflammatory such as interleukin-10 (IL-10) and transforming growth factor beta (TGF-ß) in vivo and in vitro. Furthermore, AG treatment down-regulated inflammasome NLRP3 and apoptosis genes caspase3 and caspase9, and up-regulated autophagy protein light chain 3 (LC3) by regulating the PI3K/Akt signaling pathway in vitro. Our results suggest that AG can reduce the expression of NLRP3 and alleviate the inflammatory response from MG infection by inducing autophagy, probably by modulating PI3K/Akt signaling pathway. This study demonstrates that AG can be used as a specific target to prevent and treat MG infection effectively.

Mycoplasma gallisepticum escapes the host immune response via gga-miR-365-3p/SOCS5/STATs axis.

A disruption in the expression of gga-miR-365-3p was confirmed in the Mycoplasma gallisepticum (MG)-infected Chicken primary alveolar type II epithelial (CP-II) cells based on previous sequencing results, but the role it plays in the infection was unclear. In the present study, we demonstrate that MG evaded cellular host immunity via a gga-miR-365-3p/SOCS5-JAK/STATs negative feedback loop. Specifically, we found that at the initial stage of MG infection in cells, gga-miR-365-3p was rapidly increased and activated the JAK/STAT signaling pathway by inhibiting SOCS5, which induced the secretion of inflammatory factors and triggered immune response against MG infection. Over time, though, the infection progressed, MG gradually destroyed the immune defences of CP-II cells. In late stages of infection, MG escaped host immunity by reducing intracellular gga-miR-365-3p and inhibiting the JAK/STAT pathway to suppress the secretion of inflammatory factors and promote MG adhesion or invasion. These results revealed the game between MG and host cell interactions, providing a new perspective to gain insight into the pathogenic mechanisms of MG or other pathogens. Meanwhile, they also contributed to novel thoughts on the prevention and control of MG and other pathogenic infections, shedding light on the immune modulating response triggered by pathogen invasion and their molecular targeting.

Extracellular HMGB1 as Inflammatory Mediator in the Progression of Mycoplasma Gallisepticum Infection.

High-mobility group box 1 (HMGB1), a member of damage-associated molecular patterns (DAMPs), is involved in the immune regulation of several infectious diseases. Mycoplasma gallisepticum (MG) infection is proved to cause an abnormal immune response, but the role of HMGB1 in MG-induced chronic respiratory disease (CRD) is unclear. In this study, we found that HMGB1 was released from the nucleus to the extracellular in macrophages upon infection with MG. Extracellular HMGB1 bound to TLR2 activating the NF-κB pathway triggering a severe inflammatory storm and promoting the progression of MG infection. More importantly, TLR4 could be activated by HMGB1 to trigger immune disorders after TLR2 was silenced. This disease process could be interrupted by ethyl pyruvate (EP) inhibition of HMGB1 release or glycyrrhizic acid (GA). Furthermore, treatment of MG-infected chickens with GA significantly alleviated immune organ damage. In conclusion, we demonstrate that HMGB1 is secreted extracellularly to form an inflammatory environment upon MG infection, triggering a further cellular inflammatory storm in a positive feedback approach. Blocking MG-induced HMGB1 release or suppression downstream of the HMGB1-TLR2/TLR4 axis may be a promising novel strategy for the treatment of CRD. Furthermore, this study may provide a theoretical reference for understanding non-LPS-activated TLR4 events.

Mycoplasma gallisepticum induced exosomal gga-miR-193a to disturb cell proliferation, apoptosis, and cytokine production by targeting the KRAS/ERK signaling pathway.

Mycoplasma gallisepticum (MG) is the main pathogen of chronic respiratory disease (CRD), an infectious disease in chickens with high morbidity. Exosomal miRNAs are emerging as important regulators in host immune response to microbial invasion. Previously, we found that gga-miR-193a was significantly up-regulated in exosomes from MG-infected primary chicken type II pneumocytes (CP-IIs). Therefore, the purpose of this study was to investigate the role of exosomal gga-miR-193a in MG infection. Exosomes were isolated and identified via ultracentrifugation, transmission electron microscopy, and nanoparticle-tracking analysis. Real-time quantitative PCR and Western blot were used to detect the gene expression. Enzyme-linked immunosorbent assay was used to examine the levels of the inflammatory cytokines. CCK-8 and flow cytometry assays were applied to analyze the cell functions. The results showed that MG infection induced high expression of gga-miR-193a in exosomes from CP-IIs. Moreover, exosomes secreted by MG-infected CP-IIs could selectively transport gga-miR-193a into DF-1 cells. Exosomal gga-miR-193a internalized by DF-1 cells inhibited cell proliferation, promoted apoptosis, and increased interleukin-1ß and tumor necrosis factor-α secretions by targeting the RAS/ERK signaling pathway. These results suggest that MG induced the secretion of gga-miR-193a by exosomes to damage the life activities of normal cells, which partially interpreted the mechanism of MG establishing systemic chronic infection in the body.

Lnc90386 Sponges miR-33-5p to Mediate Mycoplasma gallisepticum-Induced Inflammation and Apoptosis in Chickens via the JNK Pathway.

Mycoplasma gallisepticum (MG) is one of the most important pathogens, that causes chronic respiratory disease (CRD) in chickens. Long non-coding RNAs (lncRNAs) are emerging as new regulators for many diseases and some lncRNAs can function as competing endogenous RNAs (ceRNAs) to regulate mRNAs by competitively binding to miRNAs. Here, we found that miR-33-5p was significantly up-regulated both in MG-infected chicken embryonic lungs and chicken embryo fibroblast cells (DF-1), and Lnc90386 negatively correlated with miR-33-5p. miR-33-5p, as a new regulator for MG infection, repressed apoptosis, inflammatory factors in DF-1 cells by targeting JNK1. Further analyses showed that Lnc90386 sponged miR-33-5p to weaken its inhibitory effect on JNK1, forming the ceRNA regulatory network. Furthermore, knockdown of Lnc90386 significantly inhibited apoptosis and inflammatory factors, and promoted DF-1 cells proliferation. However, co-treatment with miR-33-5p inhibitor and Lnc90386 siRNA showed that knockdown of Lnc90386 could partially eliminate the inhibiting effect of miR-33-5p inhibitor on inflammation, cell apoptosis and proliferation. In conclusion, Lnc90386 sponges miR-33-5p to defend against MG infection by inhibiting the JNK signaling pathway.

Evaluation of Glycyrrhizic Acid Therapeutic Effect and Safety in Mycoplasma gallisepticum (HS Strain)-Infected Arbor Acres Broilers.

This study was conducted to evaluate the therapeutic effects and safety of GA in MG-infected broilers. Our results showed that the minimum inhibitory concentration of GA was 31.25 µg/mL. Moreover, GA inhibited the expression of MG adhesion protein (pMGA1.2) in the broilers' lungs. GA treatment clearly decreased the morbidity of CRD and mortality in the MG-infected broilers. Compared with the model group, GA treatment significantly decreased gross air sac lesion scores and increased average weight gain and feed conversion rate in the MG-infected broilers. Histopathological examination showed GA treatment attenuated MG-induced trachea, immune organ and liver damage in the broilers. Moreover, GA treatment alone did not induce abnormal morphological changes in these organs in the healthy broilers. Compared with the model group, serum biochemical results showed GA treatment significantly decreased the content of total protein, albumin, globulin, alanine aminotransferase, aspartate aminotransferase, total bilirubin, creatinine, uric acid, total cholesterol, and increased the content of albumin/globulin, alkaline phosphatase, apolipoprotein B and apolipoprotein A-I. In conclusion, GA displayed a significant therapeutic efficacy regarding MG infection and had no adverse effects on the broilers (100 mg/kg/d).

Andrographolide attenuates Mycoplasma gallisepticum-induced inflammation and apoptosis by the JAK/PI3K/AKT signal pathway in the chicken lungs and primary alveolar type II epithelial cells.

Mycoplasma gallisepticum (MG) is the primary etiologic agent of chronic respiratory disease (CRD) in chickens. Respiratory tract inflammation and apoptosis are the main features of CRD. Andrographolide (Andro), a natural small molecule compound, is known for its excellent anti-pathogenic and anti-inflammatory properties. Hence, this study was to evaluate the anti-inflammation and anti-apoptosis effects of Andro as well as the underlying mechanism in the chicken lungs and primary alveolar type II epithelial cells (AEC II). Results showed Andro had no side effects on AEC II viability at concentrations below 200 µg/ml. Compared with the model group, terminal deoxynucleotidyl transferase-mediated dUTP nick endlabeling (TUNEL), western blot (WB), quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assays (ELISA) results showed Andro treatment significantly reduced apoptosis in the chicken lungs and AEC II, and down-regulated the expression levels of the protein of MG adhesin 1.2 (pMGA1.2), IL-1ß, TNF-α, IL-6, Bax, Caspase 9 and Caspase 3, and up-regulated the expression levels of Bcl-2 and Bcl-xL in the chicken lungs, serum and AEC II (P ≤ 0.05). Moreover, Andro inhibited the MG-induced JAK/PI3K/AKT signal pathway activation in the chicken lungs and AEC II. Inhibiting of the JAK/PI3K/AKT signal pathway significantly alleviated MG-induced inflammation and apoptosis in the AEC II. Andro may exert an anti-inflammatory and anti-apoptotic effect by inhibiting the JAK/PI3K/AKT signal pathway in the chicken lungs and AEC II. In conclusion, Andro could act as a potential agent against MG infection by inhibiting the JAK/PI3K/AKT signal pathway and pMGA1.2 expression in the chickens.

D-π-A type conjugated indandione derivatives: ultrafast broadband nonlinear absorption responses and transient dynamics.

The ultrafast nonlinear optical response of two 1,3-indandione derivatives (INB3 and INT3) was systematically investigated by the femtosecond Z-scan and pump-probe technique at multiple visible and near infrared wavelengths. Both compounds show strong broadband nonlinear absorption (NLA) and different wavelength-dependent two-photon absorption (TPA) characteristics in the range of 650-1100 nm. The TPA cross section of trithiophene-based compound INT3 was found to be larger than that of triphenylamine-based compound INB3 in the red region (650-800 nm), which is attributed to its longer π-conjugated structure and better molecular planarity. Interestingly, the effective NLA of INB3 was found to be larger than INT3 in the NIR region (800-1100 nm), which is related to the excited state absorption (ESA) induced by TPA. The ultrafast dynamics of both compounds were investigated by femtosecond transient absorption spectroscopy, which revealed a broadband ESA including several relaxation processes. This work extends nonlinear optical research on indandione derivatives, and the results suggest that these derivatives are promising candidates for optical limiting applications.

Correction: D-π-A type conjugated indandione derivatives: ultrafast broadband nonlinear absorption responses and transient dynamics.

[This corrects the article DOI: 10.1039/D2RA00349J.].

Glycyrrhizic Acid against Mycoplasma gallisepticum-Induced Inflammation and Apoptosis Through Suppressing the MAPK Pathway in Chickens.

Mycoplasma gallisepticum (MG) is the primary pathogen of chronic respiratory diseases (CRDs) in chickens. In poultry production, antibiotics are mostly used to prevent and control MG infection, but the drug resistance and residue problems caused by them cannot be ignored. Glycyrrhizic acid (GA) is derived from licorice, a herb traditionally used to treat various respiratory diseases. Our study results showed that GA significantly inhibited the mRNA and protein expression of pMGA1.2 and GapA in vitro and in vivo. Furthermore, the network pharmacology study revealed that GA most probably resisted MG infection through the MAPK signaling pathway. Our results demonstrated that GA inhibited MG-induced expression of MMP2/MMP9 and inflammatory factors through the p38 and JUN signaling pathways, but not the ERK pathway in vitro. Besides, histopathological sections showed that GA treatment obviously attenuated tracheal and lung damage caused by MG invasion. In conclusion, GA can inhibit MG-triggered inflammation and apoptosis by suppressing the expression of MMP2/MMP9 through the JNK and p38 pathways and inhibit the expression of virulence genes to resist MG. Our results suggest that GA might serve as one of the antibiotic alternatives to prevent MG infection.

DF-1 cells prevent MG-HS infection through gga-miR-24-3p/RAP1B mediated decreased proliferation and increased apoptosis.

Mycoplasma gallisepticum (MG) is a major poultry pathogen that can induce Chronic Respiratory Disease (CRD) in chickens, causing serious economic losses in the poultry industry worldwide. Increasing evidence suggests that microRNAs (miRNAs) act as a vital role in resisting microbial pathogenesis and maintaining cellular mechanism. Our previous miRNAs sequencing data showed gga-miR-24-3p expression level was significantly increased in MG-infected chicken lungs. The aim of this study is to reveal the cellular mechanism behind the MG-HS infection. We found that gga-miR-24-3p was significantly upregulated and Ras-related protein-B (RAP1B) was downregulated in chicken fibroblast cells (DF-1) with MG infection. Dual luciferase reporting assay and rescue assay confirmed that RAP1B was the target gene of gga-miR-24-3p. Meanwhile, overexpressed gga-miR-24-3p increased the levels of tumor necrosis factor alpha (TNF-α) and interleukin-1ß (IL-1ß), and significantly inhibited cell proliferation as well as promoted MG-infected DF-1 cell apoptosis, whereas inhibition of gga-miR-24-3p had the opposite effect. More importantly, the results of overexpression and knockdown of target gene RAP1B demonstrated that the presence of RAP1B promoted cell proliferation and it saved the reduced or increased cell proliferation caused by overexpression or inhibition of gga-miR-24-3p. Furthermore, the overexpression of gga-miR-24-3p could significantly inhibit the expression of MG-HS adhesion protein. Taken together, these findings demonstrate that DF-1 cells can resist MG-HS infection through gga-miR-24-3p/RAP1B mediated decreased proliferation and increased apoptosis, which provides a new mechanism of resistance to MG infection in vitro.

Exosomal miR-181a-5p reduce Mycoplasma gallisepticum (HS strain) infection in chicken by targeting PPM1B and activating the TLR2-mediated MyD88/NF-κB signaling pathway.

Mycoplasma gallisepticum (MG) is one of the most important pathogens that causes chronic respiratory disease (CRD) in chickens. Exosomes secreted from cells have been well demonstrated to deliver miRNAs to recipient cells to modulate cellular functions. The purpose of this study is to explore the underlying functions and mechanisms of exosomal miR-181a-5p in MG-HS infection. In this study, we found that miR-181a-5p expression in vivo and in vitro was significantly up-regulated after MG-HS infection. It was also upregulated in exosomes, which were derived from MG-HS-infected type-II pneumocytes cells (CP-II). In addition, exosomes secreted by MG-HS-infected CP-II were able to transfer miR-181a-5p to recipient chicken embryo fibroblast cells (DF-1), resulting in a significant upregulation of miR-181a-5p expression in recipient DF-1 cells. We further identified that Mg2+/Mn2+-dependent protein phosphatase 1B (PPM1B) was the target gene of miR-181a-5p. Overexpression of miR-181a-5p or knockdown of PPM1B activated the nuclear factor-κB (NF-κB) signaling pathway, whereas inhibition of miR-181a-5p and overexpression of PPM1B led to the opposite results. Besides, up-regulation of miR-181a-5p significantly increased the expression of toll-like receptor 2 (TLR2), myeloid differentiation factor 88 (MyD88), tumor necrosis factors alpha (TNF-α) and interleukin-1ß (IL-1ß), whereas inhibition of miR-181a-5p showed a contrary result. Up-regulation of miR-181a-5p promoted cell proliferation, cell cycle progression and inhibited apoptosis to resist MG-HS infection. Moreover, overexpression of miR-181a-5p significantly negative regulated the expression of Mycoplasma gallisepticum adhesin protein (pMGA1.2) by directly inhibiting PPM1B. Thus, we concluded that exosomal miR-181a-5p from CP-II cells activated the TLR2-mediated MyD88/NF-κB signaling pathways by directly targeting PPM1B to promote the expression of pro-inflammatory cytokines for defending against MG-HS infection in recipient DF-1 cells.

Down-regulated gga-miR-223 inhibits proliferation and induces apoptosis of MG-infected DF-1 cells by targeting FOXO3.

Mycoplasma gallisepticum (MG) is a major poultry pathogen that can induce Chronic Respiratory Disease (CRD) in chickens, causing serious economic losses in the poultry industry worldwide. Increasing evidence suggests that microRNAs (miRNAs) act as a vital role in resisting microbial pathogenesis and maintaining cellular mechanism. Our previous miRNAs sequencing data showed that gga-miR-223 expression level significantly decreased in MG-infected chicken lungs. The aim of this study was to reveal the role of gga-miR-223 in MG-induced CRD progression. We found that gga-miR-223 was remarkably down regulated and forkhead box O3 (FOXO3) was up-regulated in both MG-infected chicken embryos lungs and the chicken embryonic fibroblast cell line (DF-1) by qPCR. FOXO3 was verified as the target gene of gga-miR-223 through bioinformatics analysis and dual-luciferase reporter assay. Further studies showed that overexpressed gga-miR-223 could promote cell proliferation, cell cycle, and inhibit cell apoptosis by notably promoting the expression of cell cycle marker genes cyclin-dependent kinase 1 (CDK1), cyclin-dependent kinase 6 (CDK6) and Cyclin D1 (CCND1) and inhibiting the expression of apoptosis markers Bcl-2-like 11(BIM), FAS ligand (FASLG) and TNF-related apoptosis-inducing ligand (TRAIL). As expected, FOXO3 knockdown group got similar results. Overexpression of gga-miR-223 observably promoted cell multiplication, cell cycle progression, and inhibited apoptosis of MG-infected DF-1 cells, while inhibited gga-miR-223 had the opposite effect. Taken together, upon MG-infection, downregulated gga-miR-223 could decrease proliferation, cycle progression, and increase apoptosis through directly targeting FOXO3 to exert an aggravating MG-infectious effect.

Erratum to "Epithelial Cells Attenuate Toll-Like Receptor-Mediated Inflammatory Responses in Monocyte-Derived Macrophage-Like Cells to Mycobacterium tuberculosis by Modulating the PI3K/Akt/mTOR Signaling Pathway".

[This corrects the article DOI: 10.1155/2018/3685948.].

Simultaneous heavy metal removal and sludge deep dewatering with Fe(II) assisted electrooxidation technology.

A hybrid sludge conditioning strategy with electrooxidation and Fe(II) addition was used for heavy metal removal from sewage sludge and industrial sludge, with simultaneous sludge dewatering and stabilization. With the addition of 82 mg/g DS Fe(II) and treatment time of 4.5 h, heavy metal removals of 72.95% and 78.49% for Cu, 66.29% and 84.26% for Zn, and 36.52% and 36.99% for Pb were achieved from sewage sludge and industrial sludge samples respectively. The system pH decreased to 2.33 and 2.98 and the oxidation-reduction potential (ORP) values increased to 435.90 mV and 480.60 mV in sewage sludge and industrial sludge samples, respectively, which was conducive to the desorption and dissolution of heavy metals from sludge structures and the degradation of the organic compounds that complexed with heavy metals. In addition, the hybrid conditioning process demonstrated excellent dewatering performance due to the efficient electrochemical disintegration of sludge flocs together with the coagulation of sludge particles by Fe(III) generated via electrooxidation. The strong acidic and oxidative environment produced by the enhanced electrooxidation process was also responsible for pathogen inactivation.