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Veterinary Research Jun 2024Bovine mastitis remains a major disease in cattle world-wide. In the mammary gland, mammary epithelial cells (MEC) are sentinels equipped with receptors allowing them to...
Bovine mastitis remains a major disease in cattle world-wide. In the mammary gland, mammary epithelial cells (MEC) are sentinels equipped with receptors allowing them to detect and respond to the invasion by bacterial pathogens, in particular Escherichia coli. Lipopolysaccharide (LPS) is the major E. coli motif recognized by MEC through its interaction with the TLR4 receptor and the CD14 co-receptor. Previous studies have highlighted the role of soluble CD14 (sCD14) in the efficient recognition of LPS molecules possessing a full-length O-antigen (LPSS). We demonstrate here that MEC are able to secrete CD14 and are likely to contribute to the presence of sCD14 in milk. We then investigated how sCD14 modulates and is required for the response of MEC to LPSS. This study highlights the key role of sCD14 for the full activation of the Myd88-independent pathway by LPSS. We also identified several lncRNA that are activated in MEC in response to LPS, including one lncRNA showing homologies with the mir-99a-let-7c gene (MIR99AHG). Altogether, our results show that a full response to LPS by mammary epithelial cells requires sCD14 and provide detailed information on how milk sCD14 can contribute to an efficient recognition of LPS from coliform pathogens.
Topics: Animals; Lipopolysaccharide Receptors; Cattle; Epithelial Cells; Lipopolysaccharides; Female; Mammary Glands, Animal; Mastitis, Bovine; Milk
PubMed: 38867337
DOI: 10.1186/s13567-024-01329-3 -
Communications Biology Jun 2024Estrogen Receptor α (ERα) is a major lineage determining transcription factor (TF) in mammary gland development. Dysregulation of ERα-mediated transcriptional program...
Estrogen Receptor α (ERα) is a major lineage determining transcription factor (TF) in mammary gland development. Dysregulation of ERα-mediated transcriptional program results in cancer. Transcriptomic and epigenomic profiling of breast cancer cell lines has revealed large numbers of enhancers involved in this regulatory program, but how these enhancers encode function in their sequence remains poorly understood. A subset of ERα-bound enhancers are transcribed into short bidirectional RNA (enhancer RNA or eRNA), and this property is believed to be a reliable marker of active enhancers. We therefore analyze thousands of ERα-bound enhancers and build quantitative, mechanism-aware models to discriminate eRNAs from non-transcribing enhancers based on their sequence. Our thermodynamics-based models provide insights into the roles of specific TFs in ERα-mediated transcriptional program, many of which are supported by the literature. We use in silico perturbations to predict TF-enhancer regulatory relationships and integrate these findings with experimentally determined enhancer-promoter interactions to construct a gene regulatory network. We also demonstrate that the model can prioritize breast cancer-related sequence variants while providing mechanistic explanations for their function. Finally, we experimentally validate the model-proposed mechanisms underlying three such variants.
Topics: Humans; Enhancer Elements, Genetic; Estrogen Receptor alpha; Breast Neoplasms; Female; Gene Expression Regulation, Neoplastic; Transcription, Genetic; Gene Regulatory Networks; MCF-7 Cells; Promoter Regions, Genetic; Cell Line, Tumor
PubMed: 38862711
DOI: 10.1038/s42003-024-06400-5 -
Emerging Infectious Diseases Jul 2024In March 2024, the US Department of Agriculture's Animal and Plant Health Inspection Service reported detection of highly pathogenic avian influenza (HPAI) A(H5N1) virus...
In March 2024, the US Department of Agriculture's Animal and Plant Health Inspection Service reported detection of highly pathogenic avian influenza (HPAI) A(H5N1) virus in dairy cattle in the United States for the first time. One factor that determines susceptibility to HPAI H5N1 infection is the presence of specific virus receptors on host cells; however, little is known about the distribution of the sialic acid (SA) receptors in dairy cattle, particularly in mammary glands. We compared the distribution of SA receptors in the respiratory tract and mammary gland of dairy cattle naturally infected with HPAI H5N1. The respiratory and mammary glands of HPAI H5N1-infected dairy cattle are rich in SA, particularly avian influenza virus-specific SA α2,3-gal. Mammary gland tissues co-stained with sialic acids and influenza A virus nucleoprotein showed predominant co-localization with the virus and SA α2,3-gal. HPAI H5N1 exhibited epitheliotropism within the mammary gland, and we observed rare immunolabeling within macrophages.
Topics: Animals; Cattle; Mammary Glands, Animal; Female; Influenza A Virus, H5N1 Subtype; Orthomyxoviridae Infections; Receptors, Cell Surface; Cattle Diseases; Dairying; N-Acetylneuraminic Acid; Receptors, Virus; Influenza in Birds
PubMed: 38861554
DOI: 10.3201/eid3007.240689 -
BioRxiv : the Preprint Server For... Jun 2024Young women have increased risk of vitamin D deficiency, which may increase breast cancer incidence. Here, we assessed the anti-cancer efficacy of vitamin D in mouse...
Young women have increased risk of vitamin D deficiency, which may increase breast cancer incidence. Here, we assessed the anti-cancer efficacy of vitamin D in mouse models of young-onset breast cancer. In never-pregnant mice, vitamin D supplementation increased serum 25(OH)D and hepatic 1,25(OH)D, reduced tumor size, and associated with anti-tumor immunity. These anti-tumor effects were not replicated in a mouse model of postpartum breast cancer, where hepatic metabolism of vitamin D was suppressed post-wean, which resulted in deficient serum 25(OH)D and reduced hepatic 1,25(OH)D. Treatment with active 1,25(OH)D induced hypercalcemia exclusively in post-wean mice, highlighting metabolic imbalance post-wean. RNAseq revealed suppressed CYP450 expression postpartum. In sum, we provide evidence that vitamin D anti-tumor activity is mediated through immunomodulatory mechanisms and is ineffective in the post-wean window due to altered hepatic metabolism. These findings have implications for suppressed xenobiotic metabolism in postpartum women beyond vitamin D.
PubMed: 38854129
DOI: 10.1101/2024.05.28.596304 -
BMC Veterinary Research Jun 2024Intramammary infection is the result of invasion and multiplication of microorganisms in the mammary gland and commonly leads to mastitis in dairy animals. Although much...
BACKGROUND
Intramammary infection is the result of invasion and multiplication of microorganisms in the mammary gland and commonly leads to mastitis in dairy animals. Although much has been done to improve cows' udder health, mastitis remains a significant and costly health issue for dairy farmers, especially if subclinical. In this study, quarter milk samples from clinically healthy cows were harvested to detect pathogens via quantitative PCR (qPCR) and evaluate changes in individual milk traits according to the number of quarters infected and the type of microorganism(s). A commercial qPCR kit was used for detection of Mycoplasma bovis, Mycoplasma spp., Staphylococcus aureus, coagulase-negative staphylococci (CNS), Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis, Prototheca spp., Escherichia coli, Klebsiella spp., Enterococcus spp. and Lactococcus lactis ssp. lactis. Quarter and pooled milk information of 383 Holstein, 132 Simmental, 129 Rendena, and 112 Jersey cows in 9 Italian single-breed herds was available.
RESULTS
Among the cows with pathogen(s) present in at least 1 quarter, CNS was the most commonly detected DNA, followed by Streptococcus uberis, Mycoplasma bovis, and Streptococcus agalactiae. Cows negative to qPCR were 206 and had the lowest milk somatic cell count. Viceversa, cows with DNA isolated in ≥ 3 quarters were those with the highest somatic cell count. Moreover, when major pathogens were isolated in ≥ 3 quarters, milk had the lowest casein index and lactose content. In animals with pathogen(s) DNA isolated, the extent with whom milk yield and major solids were impaired did not significantly differ between major and minor pathogens.
CONCLUSIONS
The effect of the number of affected quarters on the pool milk quality traits was investigated in clinically healthy cows using a commercial kit. Results remark the important negative effect of subclinical udder inflammations on milk yield and quality, but more efforts should be made to investigate the presence of untargeted microorganisms, as they may be potentially dangerous for cows. For a smarter use of antimicrobials, analysis of milk via qPCR is advisable - especially in cows at dry off - to identify quarters at high risk of inflammation and thus apply a targeted/tailored treatment.
Topics: Animals; Cattle; Milk; Female; Mastitis, Bovine; DNA, Bacterial; Streptococcus; Lactation; Real-Time Polymerase Chain Reaction
PubMed: 38849801
DOI: 10.1186/s12917-024-04083-y -
Current Health Sciences Journal 2024The current study aimed to assess the possible endocrine disruptor effects on rat mammary tissue and reproductive organs during pregnancy and lactation when exposed to...
The current study aimed to assess the possible endocrine disruptor effects on rat mammary tissue and reproductive organs during pregnancy and lactation when exposed to low doses of glyphosate and its combination with 2,4-dichlorophenoxyacetic acid (2,4-D) and dicamba. The study involved the exposure of pregnant Wistar rats to various regulatory-relevant doses of glyphosate, ranging from gestational day 6 until fine of the lactation period. Glyphosate doses corresponded to the European Union's glyphosate-acceptable daily intake (ADI; 0.5mg/kg bw/day) and no observed adverse effect level (NOAEL; 50mg/kg bw/day). The dose of the mixture of glyphosate, dicamba, and 2,4-D was at the European Union ADI for each herbicide namely 0.5, 0.002, and 0.3mg/kg bw/day, respectively. In the animals exposed to glyphosate NOAEL serum estradiol levels were increased compared to untreated animals, along with an upregulation of TNF-?, MMP-2, and MMP-9 as measured in mammary gland homogenates compared to non-treated animals. Moreover, in this group, a focally acute inflammatory infiltrate was observed in the mammary gland. Our study showed that short-term exposure to glyphosate at doses that are set as safe by regulators and thus without risk corroborated with a particular physiological state as gestation and lactation, can give rise to inflammatory changes in breast tissue in rats. These findings support the need for further evaluation of glyphosate and mixtures of glyphosate with other pesticides for public health protection, especially for those categories vulnerable to the potential endocrine disruptor properties of these pesticides such as pregnant women, newborns, and children.
PubMed: 38846475
DOI: 10.12865/CHSJ.50.01.13 -
Gland Surgery May 2024Perforator flaps have revolutionized autologous breast reconstruction, introducing both free and pedicled options as well as the potential for combining flaps. These... (Review)
Review
BACKGROUND AND OBJECTIVE
Perforator flaps have revolutionized autologous breast reconstruction, introducing both free and pedicled options as well as the potential for combining flaps. These versatile techniques can be utilized in massive weight loss (MWL) patients, effectively addressing both functional and aesthetic challenges by using their excess skin. This review aims to explore literature on combined pedicled and free perforator flaps for total breast reconstruction, and share our own experience in the field.
METHODS
A PubMed search up to June 2023 employed Medical Subject Headings (MeSH) terms such as (("combined") OR ("stacked") OR ("conjoined") AND ("perforator flaps")) AND ("breast reconstruction"). Publications in English and Scandinavian languages were manually screened for relevance, and supplemental sources were also reviewed.
KEY CONTENT AND FINDINGS
Limited studies exist on using combined pedicled and free flaps for total breast reconstruction, although combined free flaps are more common. Perforators around the breast base, offer multiple flap options for single or combined use. In our series of 10 women, four underwent total breast reconstruction with a combination of flip-over internal mammary artery perforator (IMAP) flap and thoracodorsal artery perforator (TDAP) flap. Another subset of four, who were MWL patients, received combined TDAP and superior epigastric artery perforator (SEAP) flaps, along with body contouring procedures such as upper body lifts and vertical abdominoplasties, addressing excess skin and improving silhouette. One remaining MWL patient had deflated breasts restored using TDAP and SEAP flaps, along with an upper and lower body lift and vertical abdominoplasty. The last MWL patient underwent a risk-reducing mastectomy, also reconstructed with TDAP and SEAP flaps, and received an upper body lift and vertical abdominoplasty.
CONCLUSIONS
Combined perforator flap techniques for combined body contouring and breast reconstruction seems safe and especially suitable for MWL patients. They offer a surgical alternative merging body contouring and breast reconstruction in cases where free flap procedures seem less favorable due to skin laxity and deflation of donor sites. However, limited literature on the topic calls for further studies.
PubMed: 38845826
DOI: 10.21037/gs-23-397 -
PloS One 2024During lactation, the murine mammary gland is responsible for a significant increase in circulating serotonin. However, the role of mammary-derived serotonin in energy...
During lactation, the murine mammary gland is responsible for a significant increase in circulating serotonin. However, the role of mammary-derived serotonin in energy homeostasis during lactation is unclear. To investigate this, we utilized C57/BL6J mice with a lactation and mammary-specific deletion of the gene coding for the rate-limiting enzyme in serotonin synthesis (TPH1, Wap-Cre x TPH1FL/FL) to understand the metabolic contributions of mammary-derived serotonin during lactation. Circulating serotonin was reduced by approximately 50% throughout lactation in Wap-Cre x TPH1FL/FL mice compared to wild-type mice (TPH1FL/FL), with mammary gland and liver serotonin content reduced on L21. The Wap-Cre x TPH1FL/FL mice had less serotonin and insulin immunostaining in the pancreatic islets on L21, resulting in reduced circulating insulin but no changes in glucose. The mammary glands of Wap-Cre x TPH1FL/FL mice had larger mammary alveolar areas, with fewer and smaller intra-lobular adipocytes, and increased expression of milk protein genes (e.g., WAP, CSN2, LALBA) compared to TPH1FL/FL mice. No changes in feed intake, body composition, or estimated milk yield were observed between groups. Taken together, mammary-derived serotonin appears to contribute to the pancreas-mammary cross-talk during lactation with potential implications in the regulation of insulin homeostasis.
Topics: Animals; Lactation; Serotonin; Female; Mammary Glands, Animal; Mice; Liver; Tryptophan Hydroxylase; Mice, Inbred C57BL; Pancreas; Insulin
PubMed: 38837989
DOI: 10.1371/journal.pone.0304910 -
Breast Cancer Research : BCR Jun 2024The aberrant amplification of mammary luminal progenitors is at the origin of basal-like breast cancers associated with BRCA1 mutations. Integrins mediate cell-matrix...
BACKGROUND
The aberrant amplification of mammary luminal progenitors is at the origin of basal-like breast cancers associated with BRCA1 mutations. Integrins mediate cell-matrix adhesion and transmit mechanical and chemical signals that drive epithelial stem cell functions and regulate tumor progression, metastatic reactivation, and resistance to targeted therapies. Consistently, we have recently shown that laminin-binding integrins are essential for the expansion and differentiation of mammary luminal progenitors in physiological conditions. As over-expression of the laminin-binding α6 integrin (Itgα6) is associated with poor prognosis and reduced survival in breast cancer, we here investigate the role of Itgα6 in mammary tumorigenesis.
METHODS
We used Blg-Cre; Brca1; Trp53 mice, a model that phenocopies human basal-like breast cancer with BRCA1 mutations. We generated mutant mice proficient or deficient in Itgα6 expression and followed tumor formation. Mammary tumors and pretumoral tissues were characterized by immunohistochemistry, flow cytometry, RT-qPCR, Western blotting and organoid cultures. Clonogenicity of luminal progenitors from preneoplastic glands was studied in 3D Matrigel cultures.
RESULTS
We show that Itga6 deletion favors activation of p16 cell cycle inhibitor in the preneoplastic tissue. Subsequently, the amplification of luminal progenitors, the cell of origin of Brca1-deficient tumors, is restrained in Itgα6-deficient gland. In addition, the partial EMT program operating in Brca1/p53-deficient epithelium is attenuated in the absence of Itgα6. As a consequence of these events, mammary tumor formation is delayed in Itgα6-deficient mice. After tumor formation, the lack of Itgα6 does not affect tumor growth but rather alters their differentiation, resulting in reduced expression of basal cell markers.
CONCLUSIONS
Our data indicate that Itgα6 has a pro-tumorigenic role in Blg-Cre; Brca1; Trp53 mice developing basal-like mammary tumors. In particular, we reveal that Itgα6 is required for the luminal progenitor expansion and the aberrant partial EMT program that precedes the formation of BRCA1 deficient tumors.
Topics: Animals; Integrin alpha6; Female; Tumor Suppressor Protein p53; Mice; BRCA1 Protein; Breast Neoplasms; Humans; Neoplastic Stem Cells; Cell Proliferation; Stem Cells; Gene Deletion; Cell Transformation, Neoplastic
PubMed: 38835038
DOI: 10.1186/s13058-024-01851-4 -
Journal of Dairy Science May 2024This study aimed to evaluate the impact of heat stress on mammary epithelial cell (MEC) losses into milk, secretory mammary tissue structure, and mammary epithelial cell...
This study aimed to evaluate the impact of heat stress on mammary epithelial cell (MEC) losses into milk, secretory mammary tissue structure, and mammary epithelial cell activity. Sixteen multiparous Holstein cows (632 ± 12 kg BW) approximately 100 d in milk housed in climate-controlled rooms were paired by body weight and randomly allocated to one of 2 treatments, heat stress (HS) or pair feeding thermoneutral (PFTN) using 2 cohorts. Each cohort was subjected to 2 periods of 4 d each. In period 1, both treatments had ad libitum access to a common total mixed ration and were exposed to a controlled daily temperature-humidity index (THI) of 64. In period 2, HS cows were exposed to controlled cyclical heat stress (THI: 74 to 80), while PFTN cows remained at 64 THI and daily dry matter intake was matched to HS. Cows were milked twice daily, and milk yield was recorded at each milking. Individual milk samples on the last day of each period were used to quantify MEC losses by flow cytometry using butyrophilin as a cell surface marker. On the final day of period 2, individual bovine mammary tissue samples were obtained for histomorphology analysis, assessment of protein abundance, and evaluation of gene expression of targets associated with cellular capacity for milk and milk component synthesis, heat response, cellular proliferation, and autophagy. Statistical analysis was performed using the GLIMMIX procedure of SAS. Milk yield was reduced by 4.3 kg by HS (n = 7) compared with PFTN (n = 8). Independent of treatment, MEC in milk averaged 174 cells/mL (2.9% of total cells). There was no difference between HS vs. PFTN cows for MEC shed or concentration in milk. Alveolar area was reduced 25% by HS, and HS had 4.1 more alveoli than PFTN. Total number of nucleated MEC per area were greater in HS (389 ± 1.05) compared with PFTN (321 ± 1.05); however, cell number per alveolus was similar between groups (25 ± 1.5 vs. 26 ± 1.4). There were no differences in relative fold expression for GLUT1, GLUT8, CSN2, CSN3, LALBA, FASN, HSPA5, and HSPA8 in HS compared with PFTN. Immunoblotting analyses showed a decrease abundance for phosphorylated STAT5 and S6K1, and an increase in LC3 II in HS compared with PFTN. These results suggest that even if milk yield differences and histological changes occur in the bovine mammary gland after 4 d of heat exposure, MEC loss into milk, nucleated MEC number per alveolus, and gene expression of nutrient transport, milk component synthesis, and heat stress related targets are unaffected. In contrast, the abundance of proteins related to protein synthesis and cell survival decreased significantly, while an upregulation of proteins associated with autophagy in HS compared with PFTN.
PubMed: 38825136
DOI: 10.3168/jds.2024-24809