In Vivo and In Vitro Investigations on the Synthesis of Estradiol-17β by the Bovine Mammary Gland near Term

2000 ◽  
Vol 35 (3-4) ◽  
pp. 142
Author(s):  
T Janowski
Keyword(s):  
Mammary Gland ◽  
Bovine Mammary Gland ◽  
Near Term ◽  
Estradiol 17Β

In Vivo and In Vitro Investigations on the Synthesis of Estradiol-17β by the Bovine Mammary Gland near Term

2000 ◽  
Vol 35 (3-4) ◽  
pp. 142-144 ◽  
Author(s):  
T Janowski ◽  
S Zdunczyk ◽  
ES Mwaanga ◽  
J Babinski ◽  
A Ras
Keyword(s):  
Mammary Gland ◽  
Bovine Mammary Gland ◽  
Near Term ◽  
Estradiol 17Β

Phagocytosis of Staphylococcus aureus by bovine mammary gland macrophages and intracellular protection from antibiotic action in vitro and in vivo

1984 ◽  
Vol 51 (4) ◽  
pp. 513-523 ◽  
Author(s):  
Neil Craven ◽  
James C. Anderson
Keyword(s):  
Staphylococcus Aureus ◽  
Mammary Gland ◽  
Antibiotic Therapy ◽  
Bovine Mammary Gland ◽  
Lactating Cows ◽  
Colony Forming Units ◽  
Subsequent Exposure ◽  
Increased Sensitivity

SummaryMacrophages isolated from the involuted bovine mammary gland were cultured in vitro. Phagocytosis of opsonized Staphylococcus aureus occurred rapidly, but intracellular killing of bacteria was slow. Many intracellular staphylococci survived for up to 4 d exposure to extracellular cloxacillin and emerged from within the macrophages to multiply extracellularly when the antibiotic was inactivated. Rifampicin was significantly more efficient than cloxacillin in killing intracellular S. aureus after 18 h incubation, but it too failed to sterilize the cultures within 3 d. Staphylococci, which had remained viable within macrophages during 20 h incubation with extracellular cloxacillin, showed an increased sensitivity to dilute lysostaphin on subsequent exposure. A 3 d course of intramammary therapy with cloxacillin, commencing simultaneously with an infecting inoculum of ∼108 colony forming units (c.f.u.) S. aureus, apparently eliminated the infection from one quarter of the udders of each of three lactating cows, but bacteria were re-isolated from two cows after a delay of several days. However, when other quarters of the same cows were infected with ∼108 c.f.u. S. aureus which had been phagocytosed by autologous mammary macrophages, similar simultaneous antibiotic therapy failed to affect these infections. The in vitro and in vivo findings indicate the significance of intracellular survival of S. aureus as a factor contributing to failure of antibiotic therapy.

scholarly journals Mammary gland 3D cell culture systems in farm animals

2021 ◽  
Vol 52 (1) ◽  
Author(s):  
Laurence Finot ◽  
Eric Chanat ◽  
Frederic Dessauge
Keyword(s):  
Cell Culture ◽  
Mammary Gland ◽  
Bacterial Infections ◽  
Three Dimensional ◽  
3D Cell Culture ◽  
Farm Animals ◽  
Culture Systems ◽  
Cell Culture Systems

AbstractIn vivo study of tissue or organ biology in mammals is very complex and progress is slowed by poor accessibility of samples and ethical concerns. Fortunately, however, advances in stem cell identification and culture have made it possible to derive in vitro 3D “tissues” called organoids, these three-dimensional structures partly or fully mimicking the in vivo functioning of organs. The mammary gland produces milk, the source of nutrition for newborn mammals. Milk is synthesized and secreted by the differentiated polarized mammary epithelial cells of the gland. Reconstructing in vitro a mammary-like structure mimicking the functional tissue represents a major challenge in mammary gland biology, especially for farm animals for which specific agronomic questions arise. This would greatly facilitate the study of mammary gland development, milk secretion processes and pathological effects of viral or bacterial infections at the cellular level, all with the objective of improving milk production at the animal level. With this aim, various 3D cell culture models have been developed such as mammospheres and, more recently, efforts to develop organoids in vitro have been considerable. Researchers are now starting to draw inspiration from other fields, such as bioengineering, to generate organoids that would be more physiologically relevant. In this chapter, we will discuss 3D cell culture systems as organoids and their relevance for agronomic research.

scholarly journals Fine-tuning of Epithelial EGFR signals Supports Coordinated Mammary Gland Development

2020 ◽  
Author(s):  
Alexandr Samocha ◽  
Hanna M. Doh ◽  
Vaishnavi Sitarama ◽  
Quy H. Nguyen ◽  
Oghenekevwe Gbenedio ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Mammary Epithelial Cells ◽  
Mammary Epithelium ◽  
Gene Signature ◽  
Mammary Epithelial ◽  
Fine Tuning ◽  
Basal Cells ◽  
Stem And Progenitor Cells

SummaryDuring puberty, robust morphogenesis occurs in the mammary gland; stem- and progenitor-cells develop into mature basal- and luminal-cells to form the ductal tree. The receptor signals that govern this process in mammary epithelial cells (MECs) are incompletely understood. The EGFR has been implicated and here we focused on EGFR’s downstream pathway component Rasgrp1. We find that Rasgrp1 dampens EGF-triggered signals in MECs. Biochemically and in vitro, Rasgrp1 perturbation results in increased EGFR-Ras-PI3K-AKT and mTORC1-S6 kinase signals, increased EGF-induced proliferation, and aberrant branching-capacity in 3D cultures. However, in vivo, Rasgrp1 perturbation results in delayed ductal tree maturation with shortened branches and reduced cellularity. Rasgrp1-deficient MEC organoids revealed lower frequencies of basal cells, the compartment that incorporates stem cells. Molecularly, EGF effectively counteracts Wnt signal-driven stem cell gene signature in organoids. Collectively, these studies demonstrate the need for fine-tuning of EGFR signals to properly instruct mammary epithelium during puberty.

Xanthine oxidase/dehydrogenase in mammary gland of mouse: relationship to mammogenesis and lactogenesis in vivo and in vitro

1991 ◽  
Vol 58 (4) ◽  
pp. 401-409 ◽  
Author(s):  
Thomas J. Hayden ◽  
Denise Brennan ◽  
Katherine Quirke ◽  
Paddie Murphy
Keyword(s):  
Mammary Gland ◽  
Xanthine Oxidase ◽  
Post Partum ◽  
Explant Culture ◽  
Placental Lactogen ◽  
Early Event ◽  
Histological Differentiation ◽  
Variant Enzyme

SummaryXanthine oxidase/dehydrogenase (XO/XDH) increases at mid gestation in mammary gland but not in liver of the mouse and remains elevated until the pups are weaned at 20 d post partum. The increase in enzyme activity is due neither to alteration in activators or inhibitors nor to a production of a variant enzyme with altered catalytic properties. The increase is preceded in vivo by a surge of prolactin-like activity (placental lactogen) in plasma, and prolactin is required for induction of XO/XDH in explant culture in vitro. Induction of XO/XDH in vivo and in vitro precedes the full histological differentiation of the gland. In addition, induction of XO/XDH in vitro occurs more rapidly and at lower concentrations of prolactin than does histological differentiation. Thus although XO/XDH is present in milk, increased XO/XDH activity is an early event in mammogenesis in vivo and in vitro rather than a terminal component of differentiation.

scholarly journals Evidence that the stimulation of lipogenesis in the mammary glands of starved lactating rats re-fed with a chow diet is dependent on continued hepatic gluconeogenesis during the absorptive period. Effects of a gluconeogenic inhibitory, mercaptopicolinic acid, in vivo

1985 ◽  
Vol 228 (3) ◽  
pp. 727-733 ◽  
Author(s):  
D H Williamson ◽  
V Ilic ◽  
R G Jones
Keyword(s):  
Mammary Gland ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Mammary Glands ◽  
Hepatic Glycogen ◽  
Chow Diet ◽  
Hepatic Gluconeogenesis ◽  
Rapid Stimulation ◽  
Stimulation Of

The rapid stimulation of lipogenesis in mammary gland that occurs on re-feeding starved lactating rats with a chow diet was decreased (60%) by injection of mercaptopicolinic acid, an inhibitor of hepatic gluconeogenesis at the phosphoenolpyruvate carboxykinase step. Mercaptopicolinate had no effect on lipogenesis in mammary glands of fed lactating rats. The inhibition of lipogenesis persisted in vitro when acini from mammary glands of re-fed rats treated with mercaptopicolinate were incubated with [1-14C]glucose. Mercaptopicolinate added in vitro had no significant effect on lipogenesis in acini from starved-re-fed lactating rats. Mercaptopicolinate prevented the deposition of glycogen and increased the rate of lipogenesis in livers of starved-re-fed lactating rats, whereas it had no significant effect on livers of fed lactating rats. Administration of intraperitoneal glucose restored the rate of mammary-gland lipogenesis in re-fed rats treated with mercaptopicolinate to the values for re-fed rats. Hepatic glycogen deposition was also restored, and the rate of hepatic lipogenesis was stimulated 5-fold. It is concluded that stimulation of mammary-gland lipogenesis on re-feeding with a chow diet after a period of starvation is in part dependent on continued hepatic gluconeogenesis during the absorptive period. Possible sources of the glucose precursors are discussed.

A distal region, hypersensitive to DNase I, plays a key role in regulating rabbit whey acidic protein gene expression

2001 ◽  
Vol 359 (3) ◽  
pp. 557-565 ◽  
Author(s):  
Benjamin MILLOT ◽  
Marie-Louise FONTAINE ◽  
Dominique THEPOT ◽  
Eve DEVINOY
Keyword(s):  
Mammary Gland ◽  
Sequence Similarity ◽  
Distal Region ◽  
Dnase I ◽  
Whey Acidic Protein ◽  
Acidic Protein ◽  
Upstream Region ◽  
Lactating Mammary Gland

The aim of the present study was to identify the functional domains of the upstream region of the rabbit whey acidic protein (WAP) gene, which has been used with considerable efficacy to target the expression of several foreign genes to the mammary gland. We have shown that this region exhibits three sites hypersensitive to DNase I digestion in the lactating mammary gland, and that all three sites harbour elements which can bind to Stat5 in vitro in bandshift assays. However, not all hypersensitive regions are detected at all stages from pregnancy to weaning, and the level of activated Stat5 detected in the rabbit mammary gland is low except during lactation. We have studied the role of the distal site, which is only detected during lactation, in further detail. It is located within a 849bp region that is required to induce a strong expression of the chloramphenicol acetyltransferase reporter gene in transfected mammary cells. Taken together, these results suggest that this region, centred around a Stat5-binding site and surrounded by a variable chromatin structure during the pregnancy–lactation cycle, may play a key role in regulating the expression of this gene in vivo. Furthermore, this distal region exhibits sequence similarity with a region located around 3kb upstream of the mouse WAP gene. The existence of such a distal region in the mouse WAP gene may explain the differences in expression between 4.1 and 2.1kb mouse WAP constructs.

Sign in / Sign up

Export Citation Format

Share Document