Altered molecular expression of the TLR4/NF-κB signaling pathway in mammary tissue of Chinese Holstein cattle with mastitis

An Explainable Deep Learning Classifier of Bovine Mastitis Based on Whole-Genome Sequence Data-Circumventing the p >> n Problem

The serious drawback underlying the biological annotation of whole-genome sequence data is the p >> n problem, which means that the number of polymorphic variants (p) is much larger than the number of available phenotypic records (n). We propose a way to circumvent the problem by combining a LASSO logistic regression with deep learning to classify cows as susceptible or resistant to mastitis, based on single nucleotide polymorphism (SNP) genotypes. Among several architectures, the one with 204,642 SNPs was selected as the best. This architecture was composed of two layers with, respectively, 7 and 46 units per layer implementing respective drop-out rates of 0.210 and 0.358. The classification of the test data resulted in AUC = 0.750, accuracy = 0.650, sensitivity = 0.600, and specificity = 0.700. Significant SNPs were selected based on the SHapley Additive exPlanation (SHAP). As a final result, one GO term related to the biological process and thirteen GO terms related to molecular function were significantly enriched in the gene set that corresponded to the significant SNPs. Our findings revealed that the optimal approach can correctly predict susceptibility or resistance status for approximately 65% of cows. Genes marked by the most significant SNPs are related to the immune response and protein synthesis.

Toll like receptor 4 (TLR4) gene polymorphism and its association with somatic cell score and milk production traits in Indian dromedary camels

Our study aimed to explore the genetic variation in the Toll-like receptor 4 (TLR4) gene and establish its association with somatic cell score (SCS) and milk production traits in four Indian camel breeds namely Bikaneri, Kachchhi, Jaisalmeri and Mewari. TLR4 gene fragment of 573 bp spanning 5' UTR, exon-1 and partial intron-1 region was amplified and genotyped using the PCR-sequence based typing method. Only one SNP located at position C472T was identified. Genotyping revealed two alleles (C and T) and three genotypes: CC, CT and TT. The genotype frequencies for CC, CT and TT were 0.116, 0.326 and 0.558 and allele frequencies for C and T alleles were 0.279 and 0.721, respectively. Association study inferred that the effect of genotype on SCS, lactation yield (LY) and peak yield (PY) was non-significant however heterozygote (CT) genotypes recorded lower SCS and higher LY and PY. It can be concluded that the TLR4 gene possesses limited genetic variation, depicting polymorphism at a single locus in Indian camel breeds with a predominance of the TT genotype. The association study indicated that heterozygote animals possess better udder health and production performance, the statistical significance of which needs to be established using a large data set.

SNP Analysis of TLR4 Promoter and Its Transcriptional Factor Binding Profile in Relevance to Bovine Subclinical Mastitis

Bovine mastitis is a complex infectious disease that develops in the mammary gland, predominantly caused by a bacterial infection of mammary tissue. Genetic variability of mastitis is well established and depends upon different quantitative trait loci (QTL) related to mastitis resistance or susceptibility. The susceptibility is often attributed to single-nucleotide polymorphisms (SNPs) in the variable cow breed genomes. Several global investigative attempts have resulted in studies mapping mastitis to the variations in the relevant genes. Reports have been attributed to dramatic genetic expression changes in Toll-Like Receptor 4 (TLR4) genes in mastitis-positive cows. However, the mechanism behind this variable genetic expression of TLR4 genes has been studied poorly. The present study aims to investigate SCM through various screening tests like somatic cell count (SCC), electric conductivity (EC), pH, and California mastitis test (CMT) in milk samples. This study also aims to investigate possible mechanisms behind this variable expression of TLR4 by comparative SNP evaluation and transcriptional factor profile mining. So that the important genetic mutations and effects thereof can be exploited in selecting specific breeds with higher mastitis resistance and milk yield. Seventy Holstein Frisian (HF) crossbred dairy cows were selected in the present study. The animals were screened based on various diagnostic tests (SCC, pH, EC, and CMT). Blood samples (5 mL) were collected for extraction of DNA followed by amplification of PPR1 and PPR2 of the promoter region and 5'UTR of the bovine TLR4 gene using specific primers. Sanger's enzymatic DNA sequencing technique sequenced the amplified PCR products. Further, the identification of SNPs was done through various bioinformatic tools used in this study. The findings of the present study revealed that CMT, EC, pH, and SCC could be used for the early detection of subclinical mastitis. In the present study, a significant increase in the EC, pH, and SCC in milk samples of animals affected with SCM was found in comparison to the healthy animals. The present study also revealed 16 SNPs falling in TLR4 promoter and 5' untranslated region (5'UTR) sequences in mastitis-positive genotypes compared to reference genomes. The study also investigates the potential transcriptional factor program deployed in response to variable mastitis development resistance. In the present study, the allelic and genotype frequencies of all SNP variants in the three regions viz., PPR1, PPR2, and 5'UTR, were the same indicating the absence of heterozygous condition at the respective loci. The present study has wide applicability for researchers developing mastitis-resistant breeding programs and the data generated may aid in the selection of better genetic breeds. The transcription factor binding profiles can serve as concrete leads about the studies on bovine mastitis at the molecular level and may also aid global research groups working on transcription factor (TF)-based molecular pathology of mastitis.

Coexpression analysis of lncRNAs and mRNAs identifies potential regulatory long noncoding RNAs involved in the inflammatory effects of lipopolysaccharide on bovine mammary epithelial cells

BACKGROUND

The infection of bovine mammary glands by pathogenic microorganisms not only causes animal distress but also greatly limits the development of the dairy industry and animal husbandry. A deeper understanding of the host's initial response to infection may increase the accuracy of selecting drug-resistant animals or facilitate the development of new preventive or therapeutic intervention strategies. In addition to their functions of milk synthesis and secretion, bovine mammary epithelial cells (BMECs) play an irreplaceable role in the innate immune response. To better understand this process, the current study identified differentially expressed long noncoding lncRNAs (DE lncRNAs) and mRNAs (DE mRNAs) in BMECs exposed to Escherichia coli lipopolysaccharide (LPS) and further explored the functions and interactions of these lncRNAs and mRNAs.

RESULTS

In this study, transcriptome analysis was performed by RNA sequencing (RNA-seq), and the functions of the DE mRNAs and DE lncRNAs were predicted by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Next, we constructed a modulation network to gain a deeper understanding of the interactions and roles of these lncRNAs and mRNAs in the context of LPS-induced inflammation. A total of 231 DE lncRNAs and 892 DE mRNAs were identified. Functional enrichment analysis revealed that pathways related to inflammation and the immune response were markedly enriched in the DE genes. In addition, research results have shown that cell death mechanisms, such as necroptosis and pyroptosis, may play key roles in LPS-induced inflammation.

CONCLUSIONS

In summary, the current study identified DE lncRNAs and mRNAs and predicted the signaling pathways and biological processes involved in the inflammatory response of BMECs that might become candidate therapeutic and prognostic targets for mastitis. This study also revealed several possible pathogenic mechanisms of mastitis.

DNA Polymorphisms and mRNA Levels of Immune Biomarkers as Candidates for Inflammatory Postpartum Disorders Susceptibility in Italian Buffaloes

The immunological genes that may interact with inflammatory postpartum diseases in Italian buffaloes were examined in this study. A total number of 120 female Italian buffaloes (60 normal and 60 with inflammatory reproductive diseases) were employed. Each buffalo's jugular vein was pierced to get five milliliters of blood. To obtain whole blood and extract DNA and RNA, the blood was placed within tubes containing sodium fluoride or EDTA anticoagulants. The immunological (IKBKG, LGALS, IL1B, CCL2, RANTES, MASP2, HMGB1, and S-LZ) genes' nucleotide sequence differences between healthy buffaloes and buffaloes affected by inflammatory reproductive diseases were found by employing PCR-DNA sequencing. According to Fisher's exact test (p ˂ 0.01), there were noticeably different probabilities of all major nucleotide changes spreading among buffalo groups with and without reproductive problems. Buffaloes were significantly more likely to express the examined genes when they had inflammatory reproductive diseases. The outcomes might support the significance of these markers' nucleotide variations and gene expression patterns as indicators of the prevalence of inflammatory reproductive disorders and provide a workable buffalo management policy.

Integrated analysis of inflammatory mRNAs, miRNAs, and lncRNAs elucidates the molecular interactome behind bovine mastitis

Mastitis is known as intramammary inflammation, which has a multifactorial complex phenotype. However, the underlying molecular pathogenesis of mastitis remains poorly understood. In this study, we utilized a combination of RNA-seq and miRNA-seq techniques, along with computational systems biology approaches, to gain a deeper understanding of the molecular interactome involved in mastitis. We retrieved and processed one hundred transcriptomic libraries, consisting of 50 RNA-seq and 50 matched miRNA-seq data, obtained from milk-isolated monocytes of Holstein-Friesian cows, both infected with Streptococcus uberis and non-infected controls. Using the weighted gene co-expression network analysis (WGCNA) approach, we constructed co-expressed RNA-seq-based and miRNA-seq-based modules separately. Module-trait relationship analysis was then performed on the RNA-seq-based modules to identify highly-correlated modules associated with clinical traits of mastitis. Functional enrichment analysis was conducted to understand the functional behavior of these modules. Additionally, we assigned the RNA-seq-based modules to the miRNA-seq-based modules and constructed an integrated regulatory network based on the modules of interest. To enhance the reliability of our findings, we conducted further analyses, including hub RNA detection, protein-protein interaction (PPI) network construction, screening of hub-hub RNAs, and target prediction analysis on the detected modules. We identified a total of 17 RNA-seq-based modules and 3 miRNA-seq-based modules. Among the significant highly-correlated RNA-seq-based modules, six modules showed strong associations with clinical characteristics of mastitis. Functional enrichment analysis revealed that the turquoise module was directly related to inflammation persistence and mastitis development. Furthermore, module assignment analysis demonstrated that the blue miRNA-seq-based module post-transcriptionally regulates the turquoise RNA-seq-based module. We also identified a set of different RNAs, including hub-hub genes, hub-hub TFs (transcription factors), hub-hub lncRNAs (long non-coding RNAs), and hub miRNAs within the modules of interest, indicating their central role in the molecular interactome underlying the pathogenic mechanisms of S. uberis infection. This study provides a comprehensive insight into the molecular crosstalk between immunoregulatory mRNAs, miRNAs, and lncRNAs during S. uberis infection. These findings offer valuable directions for the development of molecular diagnosis and biological therapies for mastitis.

Rhoifolin protects cecal ligation and puncture induced sepsis mice model by regulating inflammatory pathway

Sepsis is a systemic infection affects several organs, which needs novel therapy for the management of it, thus protective effect of Rhoifolin was estimated against sepsis. Cecal ligation and puncture (CLP) method was used to induce sepsis and thereafter mice were treated with rhoifolin (10 and 20 mg/kg, p.o.) for one week. Food intake and survival rate was determined sepsis mice, moreover liver function test and cytokines was estimated in the serum of sepsis mice. In the lung tissue homogenate, oxidative stress parameters were determined, histopathological analysis was performed in liver and lung tissue of sepsis mice. Food intake and percentage of survival was improved in rhoifolin treated group than sham group. Level of liver function enzyme and cytokine was reduced significantly in the serum of rhoifolin treated sepsis mice. Treatment with rhoifolin ameliorates the altered oxidative stress parameters, and mRNA expression of Toll-like receptor 4 (TLR-4) in lung tissue of sepsis mice. Histopathological changes were also reverse in rhoifolin treated group than sham group of mice. In conclusion, result of report indicates Rhoifolin treatment reduces oxidative stress and inflammation in CLP induced sepsis mice, as it regulates TLR4/MyD88/NF-κB pathway.

Candidate genes for mastitis resistance in dairy cattle: a data integration approach

BACKGROUND

Inflammation of the mammary tissue (mastitis) is one of the most detrimental health conditions in dairy ruminants and is considered the most economically important infectious disease of the dairy sector. Improving mastitis resistance is becoming an important goal in dairy ruminant breeding programmes. However, mastitis resistance is a complex trait and identification of mastitis-associated alleles in livestock is difficult. Currently, the only applicable approach to identify candidate loci for complex traits in large farm animals is to combine different information that supports the functionality of the identified genomic regions with respect to a complex trait.

METHODS

To identify the most promising candidate loci for mastitis resistance we integrated heterogeneous data from multiple sources and compiled the information into a comprehensive database of mastitis-associated candidate loci. Mastitis-associated candidate genes reported in association, expression, and mouse model studies were collected by searching the relevant literature and databases. The collected data were integrated into a single database, screened for overlaps, and used for gene set enrichment analysis.

RESULTS

The database contains candidate genes from association and expression studies and relevant transgenic mouse models. The 2448 collected candidate loci are evenly distributed across bovine chromosomes. Data integration and analysis revealed overlaps between different studies and/or with mastitis-associated QTL, revealing promising candidate genes for mastitis resistance.

CONCLUSION

Mastitis resistance is a complex trait influenced by numerous alleles. Based on the number of independent studies, we were able to prioritise candidate genes and propose a list of the 22 most promising. To our knowledge this is the most comprehensive database of mastitis associated candidate genes and could be helpful in selecting genes for functional validation studies.

Effect of Ginseng Sapogenin Protopanaxadiol-Enriched Rice (DJ-PPD) on Immunomodulation

Protopanaxadiol (PPD), a gut microbiome-induced ginseng metabolite, has positive immune effects. We previously reported the immune-boosting and anti-inflammatory effects of PPD-enricshed rice seed extracts in normal and inflammatory cell environments, respectively. In the present study, the immunomodulatory activity of PPD-enriched transgenic rice seed extract (DJ-PPD), which exhibited the highest immune-related activity among all available extracts, was compared with that of commercially synthesized 20s-PPD (S-PPD) and natural ginseng root extract (GE), in RAW264.7 cells. Compared with S-PPD and GE treatment, DJ-PPD treatment (i) significantly promoted NF-κB p65 and c-Jun N-terminal protein kinase (JNK) phosphorylation; (ii) upregulated IL-1β, IL-6, COX-2, TLR-4, and TNF-α expression; (iii) and increased prostaglandin E₂ (PGE₂) production. However, there were no significant differences in the effects of the three treatments containing PPD-type sapogenin or saponins on nitric oxide (NO) production and phagocytic activity. In the inflammatory cell environment, DJ-PPD treatment markedly decreased the production of LPS-induced inflammatory factors, including NO and PGE₂, as well as proinflammatory cytokine expression, by decreasing phosphorylated (p-)NF-κB p65, p-p38 MAPK, and p-JNK levels. Thus, DJ-PPD that does not require complex intestinal microbial processes to exert higher anti-inflammatory effects compared with S-PPD and GE. However, DJ-PPD exerted similar or higher immune-boosting effects (depending on inflammatory biomarkers) than S-PPD and GE. These findings indicate the potential of PPD-enriched transgenic rice as an alternative immunomodulatory agent.

Amelioration of Brain Damage after Treatment with the Methanolic Extract of Glycyrrhizae Radix et Rhizoma in Mice

Glycyrrhizae Radix et Rhizoma (GR) is a traditional herbal medicine widely used in Asian countries. GR was the most frequently used medicine among stroke patients in Donguibogam, the most representative book in Korean medicine. In the present study, we investigated the neuroprotective effects of the GR methanolic extract (GRex) on an ischemic stroke mice model. Ischemic stroke was induced by a 90 min transient middle cerebral artery occlusion (MCAO), and GRex was administered to mice with oral gavage after reperfusion of MCA blood flow. The MCAO-induced edema and infarction volume was measured, and behavioral changes were evaluated by a novel object recognition test (NORT). Immunofluorescence stains and Western blotting identified underlying mechanisms of the protective effects of GRex. GRex post-treatment in mice with MCAO showed potent effects in reducing cerebral edema and infarction at 125 mg/kg but no effects when the dosage was much lower or higher than 125 mg/kg. GRex inhibited the decrease of spontaneous motor activity and novel object recognition functions. The neuroprotective effects of GRex on ischemic stroke were due to its regulation of inflammation-related neuronal cells, such as microglia and astrocytes.

Lactation mastitis: Promising alternative indicators for early diagnosis

Although lactation mastitis (LM) has been extensively researched, the incidence rate of LM remains a salient clinical problem. To reduce this incidence rate and achieve a better prognosis, early and specific quantitative indicators are particularly important. It has been found that milk electrolyte concentrations (chloride, potassium, and sodium) and electrical conductivity (EC) significantly change in the early stages of LM in an animal model. Several studies have evaluated EC for the detection of subclinical mastitis in cows. EC, chloride, and sodium content of milk were more accurate for predicting infection status than were other variables. In the early stages of LM, lactic sodium, chloride, and EC increase, but potassium decreases. However, these indicators have not been reported in the diagnosis of LM in humans. This review summarizes the pathogenesis and the mechanism of LM in terms of milk electrolyte concentration and EC, and aim to provide new ideas for the detection of sub-clinical mastitis in humans.

Immune defenses of the mammary gland epithelium of dairy ruminants

The epithelium of the mammary gland (MG) fulfills three major functions: nutrition of progeny, transfer of immunity from mother to newborn, and its own defense against infection. The defense function of the epithelium requires the cooperation of mammary epithelial cells (MECs) with intraepithelial leucocytes, macrophages, DCs, and resident lymphocytes. The MG is characterized by the secretion of a large amount of a nutrient liquid in which certain bacteria can proliferate and reach a considerable bacterial load, which has conditioned how the udder reacts against bacterial invasions. This review presents how the mammary epithelium perceives bacteria, and how it responds to the main bacterial genera associated with mastitis. MECs are able to detect the presence of actively multiplying bacteria in the lumen of the gland: they express pattern recognition receptors (PRRs) that recognize microbe-associated molecular patterns (MAMPs) released by the growing bacteria. Interactions with intraepithelial leucocytes fine-tune MECs responses. Following the onset of inflammation, new interactions are established with lymphocytes and neutrophils recruited from the blood. The mammary epithelium also identifies and responds to antigens, which supposes an antigen-presenting capacity. Its responses can be manipulated with drugs, plant extracts, probiotics, and immune modifiers, in order to increase its defense capacities or reduce the damage related to inflammation. Numerous studies have established that the mammary epithelium is a genuine effector of both innate and adaptive immunity. However, knowledge gaps remain and newly available tools offer the prospect of exciting research to unravel and exploit the multiple capacities of this particular epithelium.

Active components and molecular mechanism of Syringa oblata Lindl. in the treatment of endometritis based on pharmacology network prediction

Antibiotic treatment of endometritis was limited by the inevitable antibiotic residues and risk of bacterial resistance. Therefore, the development of safe and effective strategies for endometritis treatment is urgently needed. Syringa oblata Lindl. (SOL) showed great pharmacological potential against endometritis. However, the active components and underlying mechanism of SOL for endometritis treatment remain indeterminate. In our study, the active components and possible molecular mechanism of SOL against endometritis were predicted through computer data mining and biological networks construction. It was predicted that the main active components of SOL were luteolin, kaempferol, oleanolic acid, and rutin, and their anti-endometritis effect was mainly attributed to the TLRs/NF-κB signaling pathway. Furthermore, a green and efficient deep eutectic solvent combined with ultrasound-assisted extraction (DES-UAE) was performed and optimized to obtain high contents of total flavonoid, rutin, and luteolin. The four predicted active components in the SOL extracts were qualitatively and quantitatively analyzed by LC/MS and HPLC. Finally, the pharmacological effects of SOL and active components have been verified by Staphylococcus aureus-endometritis models in mice. H&E staining and bacterial load in uterus tissues assays initially validated the pharmacodynamic effects of SOL, and quantitative real-time PCR (RT-qPCR) and ELISA results confirmed that SOL and four active components could ameliorate the uterus injury caused by Staphylococcus aureus, the mechanism of action is related to the TLRs/NF-κB signaling pathway.

Combating Bovine Mastitis in the Dairy Sector in an Era of Antimicrobial Resistance: Ethno-veterinary Medicinal Option as a Viable Alternative Approach

Bovine mastitis (BM) is the traditional infectious condition in reared cattle which may result in serious repercussions ranging from animal welfare to economic issues. Owing to the high costs associated with preventative practices and therapeutic measures, lower milk output, and early culling, bovine mastitis is accountable for most of the financial losses suffered in cattle farming. Streptococcus agalactiae, Staphylococcus aureus, Streptococcus dysgalactiae and coliform bacteria are the predominant pathogens for bovine mastitis. In addition, the occurrence of BM has been linked to lactation stage and poor management, in the latter case, the poor stabling conditions around udder hygiene. BM occurs throughout the world, with varying rates of Streptococcus agalactiae infection in different regions. Despite the modern techniques, such as the appropriate milking practices that are applied, lower levels of pathogen vulnerability may help to prevent the development of the disease, BM treatment is primarily reliant on antibiotics for both prophylactic and therapeutic purposes. Nevertheless, as a result of the proliferation of bacterial agents to withstand the antibiotic effects, these therapies have frequently proven ineffectual, resulting in persistent BM. Consequently, alternative medicines for the management of udder inflammation have been researched, notably natural compounds derived from plants. This review focuses on BM in terms of its risk factors, pathogenesis, management, the molecular identification of causative agents, as well as the application of ethno-veterinary medicine as an alternative therapy.

The role and mechanisms of miRNA in neonatal necrotizing enterocolitis

Neonatal necrotizing enterocolitis (NEC), the most significant causes of neonatal mortality, is a disease of acute intestinal inflammation. At present, it is not clear exactly how the disease is caused, but it has been suggested that this disorder is a result of a complex interaction among prematurity, enteral feeding and inappropriate pro-inflammation response and bacterial infection of the intestine. A microRNA (miRNA) is a class of endogenous non-coding single-stranded RNA that is about 23 nucleotides long engaging in the regulation of the gene expression. Recently, numerous studies have determined that abnormal miRNA expression plays important roles in various diseases, including NEC. Here, we summarized the role of miRNAs in NEC. We introduce the biosynthetic and function of miRNAs and then describe the possible mechanisms of miRNAs in the initiation and development of NEC, including their influence on the intestinal epithelial barrier's function and regulation of the inflammatory process. Finally, this review aids in a comprehensive understanding of the current miRNA to accurately predict the diagnosis of NEC and provide ideas to find potential therapeutic targets of miRNA for NEC. In conclusion, our aims are to highlight the close relationship between miRNAs and NEC and to summarize the practical value of developing diagnostic biomarkers and potential therapeutic targets of NEC.

The Role of microRNAs in the Mammary Gland Development, Health, and Function of Cattle, Goats, and Sheep

Milk is an integral and therefore complex structural element of mammalian nutrition. Therefore, it is simple to conclude that lactation, the process of producing milk, is as complex as the mammary gland, the organ responsible for this biochemical activity. Nutrition, genetics, epigenetics, disease pathogens, climatic conditions, and other environmental variables all impact breast productivity. In the last decade, the number of studies devoted to epigenetics has increased dramatically. Reports are increasingly describing the direct participation of microRNAs (miRNAs), small noncoding RNAs that regulate gene expression post-transcriptionally, in the regulation of mammary gland development and function. This paper presents a summary of the current state of knowledge about the roles of miRNAs in mammary gland development, health, and functions, particularly during lactation. The significance of miRNAs in signaling pathways, cellular proliferation, and the lipid metabolism in agricultural ruminants, which are crucial in light of their role in the nutrition of humans as consumers of dairy products, is discussed.

Regulatory network of miRNA, lncRNA, transcription factor and target immune response genes in bovine mastitis

Pre- and post-transcriptional modifications of gene expression are emerging as foci of disease studies, with some studies revealing the importance of non-coding transcripts, like long non-coding RNAs (lncRNAs) and microRNAs (miRNAs). We hypothesize that transcription factors (TFs), lncRNAs and miRNAs modulate immune response in bovine mastitis and could potentially serve as disease biomarkers and/or drug targets. With computational analyses, we identified candidate genes potentially regulated by miRNAs and lncRNAs base pair complementation and thermodynamic stability of binding regions. Remarkably, we found six miRNAs, two being bta-miR-223 and bta-miR-24-3p, to bind to several targets. LncRNAs NONBTAT027932.1 and XR_003029725.1, were identified to target several genes. Functional and pathway analyses revealed lipopolysaccharide-mediated signaling pathway, regulation of chemokine (C-X-C motif) ligand 2 production and regulation of IL-23 production among others. The overarching interactome deserves further in vitro/in vivo explication for specific molecular regulatory mechanisms during bovine mastitis immune response and could lay the foundation for development of disease markers and therapeutic intervention.

Mining for the association of bovine mastitis linked genes to pathological signatures and Pathways

Background: Bovine mastitis is a common infectious disease with a serious threat to the dairy industry and public health. Mastitis is a polygenetic trait under the control of many genes. In the current study, our research attempted to address the role of mastitis-associated genes in various signalings including parasitic, viral, cancer and fungal diseases by using online bioinformatics software. Methods: We selected mastitis-associated genes from already published data and using online bioinformatics tools including DAVID and String classify the pathological role of relevant genes. A Venn diagram was used to show the status of overlapping genes among different biological function processes. Result: This study revealed that the genes gathered in published resources of mastitis were significantly correlated with Influenza A, Chagas disease, Leishmaniasis, Toxoplasmosis, Tuberculosis, Cancer signaling, Hepatitis B, Type I &II diabetes mellitus and Prion diseases biological pathways. Based on our findings, we concluded that mastitis-linked genes could be used as markers for many other diseases. Moreover, the Bioinformatics tools applied in the current study might be helpful in screening the genes involved in one disease and their association with other diseases as well.

Exosomal miR-193b-5p as a regulator of LPS-induced inflammation in dairy cow mammary epithelial cells

Exosomes are a type of extracellular vesicle that act as shuttles, transporting certain genetic information to other cells. MiRNA cargo within exosomes can regulate gene expression at the transcriptional level. The objective of this study was to investigate the exosomal miRNAs that regulate lipopolysaccharide (LPS)-induced inflammation in dairy cow mammary alveolar (Mac-T) cells. We found two exosome miRNAs upregulated and five exosomal miRNAs downregulated, respectively, in the LPS-stimulated Mac-T cells. MiR-193b-5p was upregulated 6.3-fold in the LPS-stimulated cell-derived exosome. Target prediction results showed that nuclear factor kappa B (NF-κB) inhibitor delta (NFKBID), transforming growth factor-beta 1 induced transcript 1 (TGFB1I1), interleukin 22 (IL-22), TNF receptor superfamily member 11b (TNFRSF11B), and Janus kinase 3 (JAK3) might be the main target genes of miR-193b-5p. After treatment of Mac-T cells with the miR-193b-5p mimic, the phosphorylation levels of inhibitor of nuclear factor-kappa Bα (IκBα) and p65 were upregulated, the level of IL-6 mRNA was upregulated, and IL-1β, TNF-α, and TGF-β mRNA levels were downregulated. After treatment of Mac-T cells with miR-193b-5p inhibitor, the phosphorylation levels of IκBα and p65 were downregulated. In summary, these findings provide strong evidence that exosomal miR-193b-5p could be a regulator of LPS-induced inflammation in Mac-T cells and reveal a new role of exosomal miRNAs in regulating dairy cow mastitis.

The Regulation of Staphylococcus aureus-Induced Inflammatory Responses in Bovine Mammary Epithelial Cells

Mastitis, an inflammatory disease, causes severe economic loss in the dairy industry, which is mainly infected by bacteria. Staphylococcus aureus (S. aureus), the major pathogenic microorganism, derived from lipoteichoic acid (LTA) has been identified to activate inflammatory responses, but the cellular or intercellular regulatory mechanism is unclear. This study mainly focused on the effects of LTA in bovine mammary epithelial cells (Mac-T) and elaborated the regulation of microRNAs (miRNAs). The results showed that LTA enhanced the messenger RNA (mRNA) expression and production of tumor necrosis factor α (TNF-α) and interleukin (IL)-6. Furthermore, LTA could activate Toll-like receptor (TLR)2/MyD88-mediated phosphoinositide 3-kinase (PI3K)/AKT pathway, and TLR2 plays a pivotal role in LTA-induced inflammatory responses. The results of qRT-PCR showed that miRNA levels increased and reached the highest at 3 h and then gradually decreased over time in Mac-T cells. In exosomes, the levels of 11 and three miRNAs were upregulated and downregulated at 24 h, respectively. In addition, miR-23a showed the highest increase in Mac-T cells treated with LTA and targeted PI3K to regulate inflammatory responses. Furthermore, Mac-T cell-derived exosomes were identified to play a cell–cell communication by promoting M1 polarization of bovine macrophages. In summary, our study demonstrated that LTA could activate inflammatory responses via TLR2/MyD88/PI3K/AKT signaling pathway, and miR-23a inhibited it by targeting PI3K. Furthermore, we found that Mac-T cell-derived exosomes might be associated with inflammatory responses by promoting M1 polarization of bovine macrophages.

Hederacoside-C Inhibition of Staphylococcus aureus-Induced Mastitis via TLR2 & TLR4 and Their Downstream Signaling NF-κB and MAPKs Pathways In Vivo and In Vitro

Hederacoside-C (HDC) is a biological active ingredient, extracted from the leaves of Hedera helix. It has been reported to have anti-inflammatory properties. However, the effects of HDC on Staphylococcus aureus (S. aureus)-induced mastitis have not been reported yet. Here, we evaluated the anti-inflammatory effects of HDC on S. aureus-induced mastitis both in vivo on mammary gland tissues and in vitro on RAW 264.7 cells. The ascertained histopathological changes and MPO activity revealed that HDC defended mammary glands from tissue destruction and inflammatory cell infiltration induced by S. aureus. The results of ELISA, western blot, and qRT-PCR indicated that HDC significantly inhibited the expressions IL-6, IL-1β, and TNF-α and enhanced the IL-10 by downregulating and upregulating their relevant genes, respectively. Furthermore, HDC markedly suppressed the TLR2 and TLR4 expressions by attenuating the MAPKs (p38, ERK, JNK) and NF-κB (p65 and IκBα) pathways followed by decreasing the phosphorylation of p38, ERK, JNK, p65, and IκBα. The above parameters enhanced the mammary gland defense and reduced inflammation. These findings suggested that HDC may have the potential to be an effective anti-inflammatory drug for the S. aureus-induced mice mastitis and in RAW 264.7 cells.

Identification of Yak's TLR4 Alternative Spliceosomes and Bioinformatic Analysis of TLR4 Protein Structure and Function

Simple Summary

In this study, yak’s TLR4 gene alternative spliceosomes were investigated using PCR amplification and cloning with an aim to improve disease-resistance in yaks and promote efficient utilization of yak’s resources. qRT-PCR was used to evaluate the expression levels of two alternatively spliced TLR4 transcripts in seven distinct yak tissues. To predict the function of proteins expressed by each TLR4 spliceosome, TLR4 protein structure and function were analyzed bioinformatically. Besides, two alternative spliceosomes of yak’s TLR4 gene were also identified, which were in line with predicted variants of the TLR4 gene in NCBI. These two alternative spliceosomes of the TLR4 gene were expressed in each tissue; however, the expression levels of these spliceosomes were significantly different in different tissue. We also observed that deletion of exon-2 in TLR4 affected the function of the corresponding protein. This study will lay a theoretical foundation for future studies on the role of two variants of yak’s TLR4 gene in disease resistance. Besides, data from this study could be analyzed further to explore the molecular mechanism associated with disease-resistance in the yak.

Abstract

In this study, the yak’s TLR4 gene alternative spliceosomes were investigated using PCR amplification and cloning to improve disease-resistance in yak and promote efficient utilization of yak’s resources. qRT-PCR was used to determine the expression levels of two alternatively spliced transcripts of the TLR4 gene in seven distinct tissues. To predict the function of proteins expressed by each TLR4 spliceosome, bioinformatic analysis of yak’s TLR4 protein structure and function was performed, which led to the identification of two alternative spliceosomes of yak’s TLR4 gene. The TLR4-X1 sequence length was 2526 bp, and it encoded full-length TLR4 protein (841 amino acids). The sequence length of the exon-2 deleted TLR4-X2 sequence was 1926 bp, and it encoded truncated TLR4 protein (641 amino acids). TLR4-X2 sequence was consistent with the predicted sequence of the TLR4 gene in GenBank. Each tissue showed significantly different expression levels of these two alternative spliceosomes. As per the bioinformatic analysis of the structure and function of TLR4 protein, deletion of exon-2 in the TLR4 gene resulted in frameshift mutations of the reading frame in the corresponding protein, which altered its ligand-binding and active sites. Besides, biological property such as substrate specificity of truncated TLR4 protein was also altered, leading to altered protein function. This study has laid a theoretical foundation for exploring the role of two variants of the TLR4 gene in yak’s disease resistance. Besides, this study’s data could be analyzed further to explore the molecular mechanism associated with disease-resistance in the yak.

Let-7d-5p suppresses inflammatory response in neonatal rats with necrotizing enterocolitis via LGALS3-mediated TLR4/NF-κB signaling pathway

Necrotizing enterocolitis (NEC) is an acute intestinal condition accounting for severe mortality and morbidity in preterm infants. This study aimed to identify the possible roles of let-7d-5p in neonatal rats with NEC. The differentially expressed genes (DEGs) related to NEC were initially screened in silico. After establishment of NEC rat models, measurement of the expression of let-7d-5p, galectin-3 (LGALS3), Toll-like receptor 4 (TLR4), and nuclear factor-κB (NF-κB) as well as proinflammatory cytokines (TNF-α, IL-1β, and IL-6) was conducted. The interaction between let-7d-5p and LGALS3 or argonaute-2 (AGO2) was identified. Gain- and loss-of-function approaches were then performed in an attempt to investigate the regulatory roles of let-7d-5p and LGALS3 in inflammation and cell apoptosis in NEC neonatal rats. Let-7d-5p was poorly expressed, whereas LGALS3, TLR4, and NF-κB were highly expressed, in the intestinal tissues of NEC rats. Overexpression of let-7d-5p resulted in decreased levels of proinflammatory factors in the intestinal tissues of NEC rats. Through sequential experimentation, let-7d-5p was identified to target LGALS3 and bind to AGO2. In addition, LGALS3 silencing or LPS treatment blocked the TLR4/NF-κB signaling pathway, thereby suppressing intestinal epithelial cell apoptosis and inflammation in NEC. Collectively, let-7d-5p might exercise its inhibitory properties in the inflammatory response and intestinal epithelial cell apoptosis in NEC neonatal rats via inactivation of the LGALS3-dependent TLR4/NF-κB signaling pathway.

Overview of Research Development on the Role of NF-κB Signaling in Mastitis

Mastitis is the inflammation of the mammary gland. Escherichia coli and Staphylococcus aureus are the most common bacteria responsible for mastitis. When mammary epithelial cells are infected by microorganisms, this activates an inflammatory response. The bacterial infection is recognized by innate pattern recognition receptors (PRRs) in the mammary epithelial cells, with the help of Toll-like receptors (TLRs). Upon activation by lipopolysaccharides, a virulent agent of bacteria, the TLRs further trigger nuclear factor-κB (NF-κB) signaling to accelerate its pathogenesis. The NF-κB has an essential role in many biological processes, such as cell survival, immune response, inflammation and development. Therefore, the NF-κB signaling triggered by the TLRs then regulates the transcriptional expression of specific inflammatory mediators to initiate inflammation of the mammary epithelial cells. Thus, any aberrant regulation of NF-κB signaling may lead to many inflammatory diseases, including mastitis. Hence, the inhibiting of NF-κB signaling has potential therapeutic applications in mastitis control strategies. In this review, we highlighted the regulation and function of NF-κB signaling in mastitis. Furthermore, the role of NF-κB signaling for therapeutic purposes in mastitis control has been explored in the current review.

Identification of Gene Modules and Hub Genes Involved in Mastitis Development Using a Systems Biology Approach

Objective

Mastitis is defined as the inflammation of the mammary gland, which impact directly on the production performance and welfare of dairy cattle. Since, mastitis is a multifactorial complex disease and the molecular pathways underlying this disorder have not been clearly understood yet, a system biology approach was used in this study to a better understanding of the molecular mechanisms behind mastitis.

Methods

Publicly available RNA-Seq data containing samples from milk of five infected and five healthy Holstein cows at five time points were retrieved. Gene Co-expression network analysis (WGCNA) approach and functional enrichment analysis were then applied with the aim to find the non-preserved module of genes that their connectivity were altered under infected condition. Hub genes were identified in the non-preserved modules and were subjected to protein-protein interactions (PPI) network construction.

Results

Among the 25 modules identified, eight modules were non-preserved and were also biologically associated with inflammation, immune response and mastitis development. Interestingly most of the hub genes in the eight modules were also densely connected in the PPI network. Of the hub genes, 250 genes were hubs in both co-expression and PPI networks and most of them were reported to play important roles in immune response or inflammatory pathways. The blue module was highly enriched in inflammatory responses and STAT1 was suggested to play an important role in mastitis development by regulating the immune related genes in this module. Moreover, a set of highly connected genes were identified such as BIRC3, PSMA6, FYN, F11R, NFKBIZ, NFKBIA, GRO1, PHB, CD3E, IL16, GSN, SOCS2, HCK, VAV1 and TLR6, which have been established to be critical for mastitis pathogenesis.

Conclusion

This study improved the understanding of the mechanisms underlying bovine mastitis and suggested eight non-preserved modules along with several most important genes with promising potential in etiology of mastitis.

Interleukin-35 reduces inflammation in acute lung injury through inhibiting TLR4/NF-κB signaling pathways

Acute lung injury (ALI) in children is a complex disease that is accompanied by an inflammatory response. The pathogenesis of ALI in children is not yet well understood. Mice with ALI exhibit inflammation of the lungs and decreased expression of interleukin (IL)-35. To investigate whether the function of IL-35 affects lipopolysaccharide (LPS)-induced ALI, IL-35 was overexpressed in cells. Enzyme-linked immunosorbent assays indicated decreased levels of IL-6 and tumor necrosis factor-α in LPS-induced and agomir-IL-35-treated murine RAW264.7 macrophages. Finally, toll-like receptor 4 (TLR4)/NF-κB signaling pathways were analyzed. The expression of TLR4, NF-κB p65 and NF-κB p50 were decreased, as was the degradation of NF-κB inhibitor-α, in LPS-induced and agomir-IL-35-treated murine RAW264.7 macrophages. The results of the present study demonstrated that IL-35 may exhibit a protective role in ALI by modulating the TLR4/NF-κB signaling pathways.

Three Novel Players: PTK2B, SYK, and TNFRSF21 Were Identified to Be Involved in the Regulation of Bovine Mastitis Susceptibility via GWAS and Post-transcriptional Analysis

Bovine mastitis is a common inflammatory disease caused by multiple factors in early lactation or dry period. Genome wide association studies (GWAS) can provide a convenient and effective strategy for understanding the biological basis of mastitis and better prevention. 2b-RADseq is a high-throughput sequencing technique that offers a powerful method for genome-wide genetic marker development and genotyping. In this study, single nucleotide polymorphisms (SNPs) of the immune-regulated gene correlative with mastitis were screened and identified by two stage association analysis via GWAS-2b-RADseq in Chinese Holstein cows. We have screened 10,058 high quality SNPs from 7,957,920 tags and calculated their allele frequencies. Twenty-seven significant SNPs were co-labeled in two GWAS analysis models [Bayesian (P < 0.001) and Logistic regression (P < 0.01)], and only three SNPs (rs75762330, C > T, PIC = 0.2999; rs88640083, A > G, PIC = 0.1676; rs20438858, G > A, PIC = 0.3366) were annotated to immune-regulated genes (PTK2B, SYK, and TNFRSF21). Identified three SNPs are located in non-coding regions with low or moderate genetic polymorphisms. However, independent sample population validation (Case-control study) data showed that three important SNPs (rs75762330, P < 0.025, OR > 1; rs88640083, P < 0.005, OR > 1; rs20438858, P < 0.001, OR < 1) were significantly associated with clinical mastitis trait. Importantly, PTK2B and SYK expression was down-regulated in both peripheral blood leukocytes (PBLs) of clinical mastitis cows and in vitro LPS (E. coli)-stimulated bovine mammary epithelial cells, while TNFRSF21 was up-regulated. Under the same conditions, expression of Toll-like receptor 4 (TLR4), AKT1, and pro-inflammatory factors (IL-1β and IL-8) were also up-regulated. Interestingly, network analysis indicated that PTK2B and SYK are co-expressed in innate immune signaling pathway of Chinese Holstein. Taken together, these results provided strong evidence for the study of SNPs in bovine mastitis, and revealed the role of SYK, PTK2B, and TNFRSF21 in bovine mastitis susceptibility/tolerance.

Rev-erbα can regulate the NF-κB/NALP3 pathway to modulate lipopolysaccharide-induced acute lung injury and inflammation

Progressive lung injury and pulmonary inflammation can be induced by an intraperitoneal injection of lipopolysaccharide (LPS). Interleukin-1β (IL-1β) is a key pro-inflammatory cytokine that can further exaggerate inflammation, which is cleaved and activated by the NALP3 inflammasome. Although the nuclear receptor Rev-erbα attenuates the level of LPS-induced pulmonary inflammation, the mechanism remains unclear. In this study, we investigated the influence of LPS-induced production of IL-1β and Rev-erbα on the development of lung inflammation. Herein, we demonstrate that Rev-erbα reduces IL-1β production and lung injury following an intraperitoneal injection of LPS, which is dependent on the NF-κB/NALP3 pathway. Thus, Rev-erbα is able to decrease the extent of acute lung injury by regulating IL-1β production. This mechanism may represent a potential novel therapeutic approach for lung injury.

Protective effects of the suppressed NF-κB/TLR4 signaling pathway on oxidative stress of lung tissue in rat with acute lung injury

The pathogenesis of acute lung injury (ALI) is characterized by lung inflammation and lung oxidative stress. The study was conducted in order to investigate the effect toll-like receptor 4 (TLR4) and nuclear factor-kappa B (NF-κB) exhibited on oxidative stress in ALI. After the rats had been assigned into different groups, arterial blood, white blood cell (WBC), lung permeability index (LPI), wet/dry (W/D) ratio, TLR4 and NF-κB expression and superoxide dismutase (SOD), myeloperoxidase (MPO), malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS) were examined. Afterward, the correlation between the levels of TLR4 and NF-κB was determined. Decreased levels of PaO₂ , SOD, MPO, and GSH accompanied by increased levels of PaCO₂ , WBC number, LPI and W/D ratio, MDA and ROS, as well as TLR4 and NF-κB expressions in the ALI, ALI + NF-κB inhibitor, and ALI + phosphate buffer saline groups were found. Inhibition of NF-κB resulted in increased PaO₂ and decreased PaCO₂ levels, WBC number, and LPI and W/D ratio. Decreased expression of NF-κB increased SOD, GSH, and MPO, but decreased MDA and ROS. We also found that NF-κB inhibition resulted in the improvement of ALI in rats. TLR4 and NF-κB expressions were negatively correlated with levels of SOD, MPO, and GSH, and positively correlated with MDA and ROS levels. In summary, our findings provided evidence that inhibition of the TLR4/NF-κB signaling pathway decreases oxidative stress, thereby improving ALI. As a result, NF-κB signaling pathway has shown potential as a therapeutic target in ALI therapy.

Pharmacological inhibition of TLR4/NF-κB with TLR4-IN-C34 attenuated microcystin-leucine arginine toxicity in bovine Sertoli cells

This study investigated the pharmacological inhibition of the toll-like receptor 4 (TLR4) genes as a measure to attenuate microcystin-LR (MC-LR) reproductive toxicity. Bovine Sertoli cells were pretreated with TLR4-IN-C34 (C34) for 1 hour. Thereafter the pretreated and non-pretreated Sertoli cells were cultured in medium containing 10% heat-activated fetal bovine serum + 80 μg/L MC-LR for 24 hours to assess the ability of TLR4-IN-C34 to attenuate the toxic effects of MC-LR. The results showed that TLR4-IN-C34 inhibited MC-LR-induced mitochondria membrane damage, mitophagy and downregulation of blood-testis barrier constituent proteins via TLR4/nuclear factor-kappaB and mitochondria-mediated apoptosis signaling pathway blockage. The downregulation of the mitochondria electron transport chain, energy production and DNA replication related genes (mt-ND2, COX-1, COX-2, ACAT, mtTFA) and upregulation of inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor-α, IL-1β, interferon-γ, IL-4, IL-10, IL-13 and transforming growth factor β1) were modulated by TLR4-IN-C34. Taken together, we conclude that TLR4-IN-C34 inhibits MC-LR-related disruption of mitochondria membrane, mitophagy and downregulation of blood-testis barrier proteins of the bovine Sertoli cell via cytochrome c release and TLR4 signaling blockage.

Sodium Selenite inhibits mitophagy, downregulation and mislocalization of blood-testis barrier proteins of bovine Sertoli cell exposed to microcystin-leucine arginine (MC-LR) via TLR4/NF-kB and mitochondrial signaling pathways blockage

This study was conducted to investigate the ameliorative effect of selenium on microcystin-LR induced toxicity in bovine Sertoli cells. Bovine Sertoli cells were pretreated with selenium (Na₂SeO₃) for 24 h after which selenium pretreated and non-pretreated Sertoli cells were cultured in medium containing 10% heat activated fetal bovine serum FBS+ 80 µg/L MC-LR to assess its ameliorative effect on MC-LR toxicity. The results show that selenium pretreatment inhibited the MC-LR induced mitophagy, downregulation and mislocalization of blood-testis barrier constituent proteins in bovine Sertoli cells via NF-kB and cytochrome c release blockage. The observed downregulation of electron transport chain (ETC) related genes (mt-ND2, COX-1, COX-2) and upregulation of inflammatory cytokines (IL-6, TNF-α, IL-1β, IFN-γ, IL-4, IL-10, 1 L-13, TGFβ1) in non-pretreated cells exposed to MC-LR were ameliorated in selenium pretreated cells. There was no significant difference (P > 0.05) in the protein levels of blood-testis barrier constituent proteins (ZO-1, occludin, connexin-43, CTNNB1, N-cadherin) and mitochondria related genes (mt-ND2, COX-1, COX-2, ACAT1, mtTFA) of selenium pretreated Sertoli cell compared to the control. Taken together, we conclude that selenium inhibits MC-LR caused Mitophagy, downregulation and mislocalization of blood-testis barrier proteins of bovine Sertoli cell via mitochondrial and TLR4/NF-kB signaling pathways blockage.

Microcystin-leucine arginine (MC-LR) induced inflammatory response in bovine sertoli cell via TLR4/NF-kB signaling pathway

Sertoli cells were treated with 0, 20, 40, 60 and 80 μg/L of MC-LR to investigate its toxic effects, mechanism of action and immune response of the cells. Our results revealed that treatment containing 20 μg/L of MC-LR was non-toxic to the cells. Treatments containing 40, 60 and 80 μg/L of MC-LR reduced the cell viability, induced nuclear morphological changes and downregulated the blood-testis barrier constituent proteins within 48 h after treatment. The toll-like receptor 4 (TLR4) and nuclear factor-kappaB (NF-kB) were activated and significantly (P < 0.05) upregulated in cells treated with 40, 60 and 80 μg/L of MC-LR compared to the control. The pro-inflammatory cytokines were upregulated within 48 h after treatment. However commencing from 72 h, upregulation of anti-inflammatory cytokines and expression of blood-testis barrier constituent proteins was observed. This study indicates that MC-LR induced inflammatory response in bovine Sertoli cell via activation of TLR4/NF-kB signaling pathway.

Comparison of microRNA Profiles between Bovine Mammary Glands Infected with Staphylococcus aureus and Escherichia coli

MicroRNAs (miRNAs) play crucial roles in regulating innate and adaptive immunity in humans and animals. Infection with E. coli or S. aureus can cause inflammation of the mammary glands, which results in significant economic losses in dairy cattle. However, the regulatory mechanisms of miRNAs in response to E. coli or S. aureus infection in bovine mammary glands have not been thoroughly explored. To discover the differential expression of miRNA in bovine mammary gland challenged with E. coli or S. aureus, we performed miRNA sequencing on tissue samples. A total of 1838 miRNAs were identified, including 580 known-miRNAs (included in the miRbase database) and 1258 predicted novel miRNAs. The miRNA expression patterns indicated that, compared with control samples, 279 miRNAs and 305 miRNAs were differentially expressed miRNAs (DIE-miRNA) in S. aureus and E. coli infected tissues, respectively. Moreover, the results of comparison the DIE-miRNAs between the E. coli and S. aureus infected groups showed that 197 DIE-miRNAs are identical, 108 DIE-miRNAs are specific to the E. coli group, and 82 DIE-miRNAs are specific to the S. aureus group. Many DIE-miRNAs, such as bta-miR-144, bta-miR-451 and bta-miR-7863, might be the useful biomarkers of mastitis caused by E. coli and S. aureus. In addition, target genes of the DIE-miRNAs were predicted. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that these DIE-miRNAs are likely involved in many immune signaling pathways, including the Toll-like receptor signaling pathways, MAPK signaling pathway, cell adhesion molecules, TGF-β signaling pathway, leukocyte trans endothelial migration, cytokine-cytokine receptor interaction, and chemokine signaling pathways. This study has provided supportive evidence that miRNAs may serve as diagnostic biomarkers of mastitis in dairy cows, and suggests potentially of effective strategies to combat mastitis.

Comparison of the effect of recombinant bovine wild and mutant lipopolysaccharide-binding protein in lipopolysaccharide-challenged bovine mammary epithelial cells

Lipopolysaccharide (LPS)-binding protein (LBP) plays a crucial role in the recognition of bacterial components, such as LPS that causes an immune response. The aim of this study was to compare the different effects of recombinant bovine wild LBP and mutant LBP (67 Ala → Thr) on the LPS-induced inflammatory response of bovine mammary epithelial cells (BMECs). When BMECs were treated with various concentrations of recombinant bovine lipopolysaccharide-binding protein (RBLBP) (1, 5, 10, and 15 μg/mL) for 12 h, RBLBP of 5 μg/mL increased the apoptosis of BMECs induced by LPS without cytotoxicity, and mutant LBP resulted in a higher cell apoptosis than wild LBP did. By gene-chip microarray and bioinformatics, the data identified 2306 differentially expressed genes that were changed significantly between the LPS-induced inflamed BMECs treated with 5 μg/mL of mutant LBP and the BMECs only treated with 10 μg/mL of LPS (fold change ≥2). Meanwhile, 1585 genes were differently expressed between the inflamed BMECs treated with 5 μg/mL of wild LBP and 10 μg/mL of LPS-treated BMECs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that these differentially expressed genes were involved in different pathways that regulate the inflammation response. It predicted that carriers of this mutation increase the risk for a more severe inflammatory response. Our study provides an overview of the gene expression profile between wild LBP and mutant LBP on the LPS-induced inflammatory response of BMECs, which will lead to further understanding of the potential effects of LBP mutations on bovine mammary glands.