Staphylococcus aureus on the effect of expression of MMPs/TIMPs and uPA system in bovine mammary fibroblasts.

BACKGROUND: Bovine mammary fibrosis is characteristic of chronic in injury in response to diverse pathogens. Staphylococcus aureus (S.aureus) is a frequent cause of mastitis in bovine and is prone to persistent infection. Diverse studies have shown MMPs/TIMPs and uPA system as a potent target for the treatment of fibrosis. However, pathogenesis of S. aureus-induced mammary fibrosis has not been completely defined. METHODS: BMFBs treated with heat-inactivated S. aureus (105, 106, and 108 CFU/mL) for 6, 12, 24, and 48 h. Total RNA and protein were isolated from the treatments and controls of BMFBs samples. MMP-1, MMP-2, MMP-3, MMP-9, MMP-13, TIMP-1, TIMP-2, COL Ⅰ, uPA, uPAR and PAI-1 gene and protein expression were examined by RT-qPCR and Western blot analysis. Gelatin zymography assay was performed to assess the levels of MMP-2 and MMP-9 enzyme secreted. RESULTS: BMFBs treated with heat-inactivated S. aureus increased mRNA and protein expression levels of MMP-1, MMP-2, MMP-3, MMP-9 and MMP-13, and heat-inactivated S. aureus induced TIMP-1, TIMP-2 and COL Ⅰ expression. There was a clear activation of MMP-2 in the presence of heat-inactivated S. aureus in the conditioned medium from the BMFBs, whereas MMP-9 was no significantly altered. Moreover, uPA system was activated in BMFBs to S. aureus. CONCLUSION: Activation of the uPA system together with its impact on the MMPs levels could play a significant role in S. aureus-induced BMFBs with mechanism of ECM metabolism, MMPs/TIMPs and uPA system could participate in bovine mammary fibrosis.

Staphylococcus aureus metal acquisition in the mastitic mammary gland.

Mastitis, resulting from mammary gland infection, is a common and painful disease associated with lactation. In addition to the impact on human and animal health, mastitis causes substantial economic losses in the dairy industry. Staphylococcus aureus is a frequent cause of mastitis worldwide. Despite significant progress in understanding S. aureus pathogenesis in general, much remains to be learned regarding virulence factors relevant in the context of mastitis. This review outlines the molecular mechanisms by which S. aureus acquires essential metals such as iron, zinc, manganese, copper, cobalt and nickel within lactating mammary glands, while exposing areas where our current knowledge is deficient. Increased understanding of how these factors facilitate bacterial survival in the lactating mammary gland can provide therapeutic targets for more effective mastitis prevention and treatment.

Contributions to human breast milk microbiome and enteromammary transfer of Bifidobacterium breve.

Increasing evidence supports the importance of the breast milk microbiome in seeding the infant gut. However, the origin of bacteria in milk and the process of milk microbe-mediated seeding of infant intestine need further elucidation. Presumed sources of bacteria in milk include locations of mother-infant and mother-environment interactions. We investigate the role of mother-infant interaction on breast milk microbes. Shotgun metagenomics and 16S rRNA gene sequencing identified milk microbes of mother-infant pairs in breastfed infants and in infants that have never latched. Although breast milk has low overall biomass, milk microbes play an important role in seeding the infant gut. Breast milk bacteria were largely comprised of Staphylococcus, Streptococcus, Acinetobacter, and Enterobacter primarily derived from maternal areolar skin and infant oral sites in breastfeeding pairs. This suggests that the process of breastfeeding is a potentially important mechanism for propagation of breast milk microbes through retrograde flux via infant oral and areolar skin contact. In one infant delivered via Caesarian section, a distinct strain of Bifidobacteria breve was identified in maternal rectum, breast milk and the infant's stool potentially suggesting direct transmission. This may support the existence of microbial translocation of this anaerobic bacteria via the enteromammary pathway in humans, where maternal bacteria translocate across the maternal gut and are transferred to the mammary glands. Modulating sources of human milk microbiome seeding potentially imply opportunities to ultimately influence the development of the infant microbiome and health.

Role of Liver X Receptor in Mastitis Therapy and Regulation of Milk Fat Synthesis.

Mastitis is important disease that causes huge economic losses in the dairy industry. In recent years, antibiotic therapy has become the primary treatment for mastitis, however, due to drug residue in milk and food safety factors, we lack safe and effective drugs for treating mastitis. Therefore, new targets and drugs are urgently needed to control mastitis. LXRα, one of the main members of the nuclear receptor superfamily, is reported to play important roles in metabolism, infection and immunity. Activation of LXRα could inhibit LPS-induced mastitis. Furthermore, LXRα is reported to enhance milk fat production, thus, LXRα may serve as a new target for mastitis therapy and regulation of milk fat synthesis. This review summarizes the effects of LXRα in regulating milk fat synthesis and treatment of mastitis and highlights the potential agonists involved in both issues.

Development of immune and microbial environments is independently regulated in the mammary gland.

Breastfeeding is important for mammals, providing immunological and microbiological advantages to neonates, together with the nutritional supply from the mother. However, the mechanisms of this functional diversity in the mammary gland remain poorly characterized. Here, we show that, similar to the gastrointestinal tract, the mammary gland develops immune and microbial environments consisting of immunoglobulin A (IgA) and the microflora, respectively, both of which are important for protecting neonates and the mother from infectious diseases. The IgA production and microflora development are coordinated in the gastrointestinal tract but seem to be independently regulated in the mammary gland. In particular, the chemokine (C-C motif) ligand 28 and poly-Ig receptor, crucial molecules for the IgA production in milk, were expressed normally in germ-free lactating mice but were almost undetectable in postweaning mothers, regardless of the microflora presence. Our findings offer insights into potentially improving the quality of breastfeeding, using both immunological and microbiological approaches.

EHS matrix incubated in media containing penicillin retains sufficient concentrations of antibiotic to inhibit growth of susceptible microorganisms.

In studying the interaction between bacteria and host cells in vitro, the latter are frequently cultured on commercially available biotic matrices such as Matrigel® or Geltrex®. To avoid contamination, host cells are commonly grown in the presence of antibiotics. However, we present here the finding that cell culture on such a matrix in the presence of antibiotics interferes with the outcome of subsequent infection experiments by virtue of diminished bacterial survival. By comparing outcomes for penicillin-susceptible and resistant strains of Staphylococcus aureus, we show that residual penicillin remains in the matrix despite the antibiotics' withdrawal from culture. Hence, the use of antibiotics should be avoided in this context.

Control mechanisms for producing antimicrobial factors in ruminant mammary gland.

Mastitis, a symptom of inflammation in mammary tissue by infection with various kinds of bacteria, causes huge economic losses in the milk industry. One of the popular methods for treatment of mastitis is antibiotics, although this prohibits milk shipping and sometimes causes resistant microbes. Therefore, a new strategy to treat mastitis without antibiotics is eagerly required around the world. Antimicrobial factors belong to innate immunity and can start their function extremely early after bacterial stimulation. These factors have antimicrobial activity for a broad spectrum of bacteria. Elucidation of causal mechanisms and functions of antimicrobial factors in the mammary gland is thought to result in suitable methods for prevention and treatment of mastitis. Therefore, this review introduces traits of some antimicrobial factors and the mechanisms for expressing, producing and secreting them in the mammary gland. For antimicrobial factors, lingual antimicrobial peptide (LAP), S100A7, cathelicidin and lactoferrin are controlled in different sites and different time courses, suggesting that antimicrobial factors play different roles for local defense against bacterial infection in the mammary gland. These findings will contribute to the development of prevention and treatment methods for mastitis.

Genome-Wide Transcriptional and Post-transcriptional Regulation of Innate Immune and Defense Responses of Bovine Mammary Gland to Staphylococcus aureus.

Staphylococcus aureus (S. aureus) is problematic for lactating mammals and public health. Understanding of mechanisms by which the hosts respond to severe invasion of S. aureus remains elusive. In this study, the genome-wide expression of mRNAs and miRNAs in bovine mammary gland cells were interrogated at 24 h after intra-mammary infection (IMI) with high or low concentrations of S. aureus. Compared to the negative control quarters, 194 highly-confident responsive genes were identified in the quarters with high concentration (109 cfu/mL) of S. aureus, which were predominantly implicated in pathways and biological processes pertaining to innate immune system, such as cytokine-cytokine receptor interaction and inflammatory response. In contrast, only 21 highly-confident genes were significantly differentially expressed in face of low concentration (106 cfu/mL) of S. aureus, which slightly perturbed the cell signaling and invoked corresponding responses like vasoconstriction, indicating limited perturbations and immunological evading. Additionally, the significant up-regulations of bta-mir-223 and bta-mir-21-3p were observed in the quarters infected by high concentration of S. aureus. Network analysis suggested that the two miRNAs' pivotal roles in defending hosts against bacterial infection probably through inhibiting CXCL14 and KIT. The significant down-regulation of CXCL14 was also observed in bovine mammary epithelial cells at 24 h post-infection of S. aureus (108 cfu/mL) in vitro. Integrated analysis with QTL database further suggested 28 genes (e.g., CXCL14, KIT, and SLC4A11) as candidates of bovine mastitis. This study first systematically revealed transcriptional and post-transcriptional responses of bovine mammary gland cells to invading S. aureus in a dosage-dependent pattern, and highlighted a complicated responsive mechanism in a network of miRNA-gene-pathway interplay.

Synergistic streptococcal phage λSA2 and B30 endolysins kill streptococci in cow milk and in a mouse model of mastitis.

Bovine mastitis results in billion dollar losses annually in the USA alone. Streptococci are among the most relevant causative agents of this disease. Conventional antibiotic therapy is often unsuccessful and contributes to development of antibiotic resistance. Bacteriophage endolysins represent a new class of antimicrobials against these bacteria. In this work, we characterized the endolysins (lysins) of the streptococcal phages λSA2 and B30 and evaluated their potential as anti-mastitis agents. When tested in vitro against live streptococci, both enzymes exhibited near-optimum lytic activities at ionic strengths, pH, and Ca(2+) concentrations consistent with cow milk. When tested in combination in a checkerboard assay, the lysins were found to exhibit strong synergy. The λSA2 lysin displayed high activity in milk against Streptococcus dysgalactiae (reduction of CFU/ml by 3.5 log units at 100 µg/ml), Streptococcus agalactiae (2 log), and Streptococcus uberis (4 log), whereas the B30 lysin was less effective. In a mouse model of bovine mastitis, both enzymes significantly reduced intramammary concentrations of all three streptococcal species (except for B30 vs. S. dysgalactiae), and the effects on mammary gland wet weights and TNFα concentrations were consistent with these findings. Unexpectedly, the synergistic effect determined for the two enzymes in vitro was not observed in the mouse model. Overall, our results illustrate the potential of endolysins for treatment of Streptococcus-induced bovine mastitis.

Probiotics in human milk and probiotic supplementation in infant nutrition: a workshop report.

Probiotics in human milk are a very recent field of research, as the existence of the human milk microbiome was discovered only about a decade ago. Current research is focusing on bacterial diversity and the influence of the maternal environment as well as the mode of delivery on human milk microbiota, the pathways of bacterial transfer to milk ducts, possible benefits of specific bacterial strains for the treatment of mastitis in mothers, and disease prevention in children. Recent advances in the assessment of early host-microbe interactions suggest that early colonisation may have an impact on later health. This review article summarises a scientific workshop on probiotics in human milk and their implications for infant health as well as future perspectives for infant feeding.

[Efficacy of application of radiofrequency scalpel and ozono-ultrasound method in dynamics of planimetric indices of the wound course process in the patients, suffering an acute purulent lactation mastitis].

The results of planimetric investigation, conducted in 82 patients, suffering an acute purulent lactation mastitis (APLM), were analyzed. Of them 42 patients (the main group) were operated on, using radiofrequency scalpel, for the postoperative wounds processing the low-frequency ultrasound and ozonated isotonic solution of sodium chloride were used. In 40 patients (group of comparison) the conventional methods of treatment of APLM were applied.

Functional adaptations of the transcriptome to mastitis-causing pathogens: the mammary gland and beyond.

Application of microarrays to the study of intramammary infections in recent years has provided a wealth of fundamental information on the transcriptomics adaptation of tissue/cells to the disease. Due to its heavy toll on productivity and health of the animal, in vivo and in vitro transcriptomics works involving different mastitis-causing pathogens have been conducted on the mammary gland, primarily on livestock species such as cow and sheep, with few studies in non-ruminants. However, the response to an infectious challenge originating in the mammary gland elicits systemic responses in the animal and encompasses tissues such as liver and immune cells in the circulation, with also potential effects on other tissues such as adipose. The susceptibility of the animal to develop mastitis likely is affected by factors beyond the mammary gland, e.g. negative energy balance as it occurs around parturition. Objectives of this review are to discuss the use of systems biology concepts for the holistic study of animal responses to intramammary infection; providing an update of recent work using transcriptomics to study mammary and peripheral tissue (i.e. liver) as well as neutrophils and macrophage responses to mastitis-causing pathogens; discuss the effect of negative energy balance on mastitis predisposition; and analyze the bovine and murine mammary innate-immune responses during lactation and involution using a novel functional analysis approach to uncover potential predisposing factors to mastitis throughout an animal's productive life.

Gigantomastia complicating pregnancy: a case report.

BACKGROUND: Mammary gigantism is a rare, cosmetically embarrassing complication of pregnancy that may ulcerate and have potentially fatal bleeding. METHODS: A case report of a 20-year old primigravida with bilateral massive breast enlargement is presented to highlight the clinical presentation and management challenges of the condition. RESULTS: She was treated with local debridement, bromocriptine, antibiotics and blood transfusion with good results. The pregnancy however terminated at 27 weeks of gestation. CONCLUSION: Gigantomastia is a rare complication of pregnancy, which may pose a major management challenge. A favorable outcome may be achieved with prompt recognition of the condition and conservative management in selected cases.

Risk factors for mammary candidosis among lactating women.

OBJECTIVES: To document the occurrence of Candida colonization and mammary candidosis among lactating women, risk factors for Candida colonization, and the relationship between Candida colonization and breastfeeding at 9 weeks postpartum. DESIGN: Prospective cohort study. SETTING: Private practice clinic in Reno, Nevada. PARTICIPANTS: 100 lactating women and their infants, and 40 nonpregnant, nonlactating women (controls). PROCEDURE: At 2 weeks postpartum, skin and milk samples were collected from the lactating women and oral samples were collected from their infants. Skin samples were collected from control subjects. All samples were cultured for Candida species. Lactating women were recontacted by phone at 9 weeks postpartum to assess infant feeding practices. MAIN OUTCOME MEASURE: Colonization with Candida species. RESULTS: None of the control subjects tested positive for Candida colonization. Of the lactating women, 23% tested positive for Candida and 20% had mammary candidosis. Risk factors for colonization of the mother were bottle use in the first 2 weeks postpartum and pregnancy duration of > 40 weeks. Of the 100 infants, 20% tested positive for Candida. Risk factors for colonization of the infant were bottle use in the first 2 weeks postpartum and presence of siblings. Among women who tested positive at 2 weeks, 43% were still breastfeeding at 9 weeks postpartum compared to 69% of the women who did not test positive (p < .05). CONCLUSION: Avoidance of bottle use early postpartum may reduce the risk of mammary candidosis. Mammary candidosis is related to early termination of breastfeeding.