Adipo-Epithelial Transdifferentiation in In Vitro Models of the Mammary Gland.

Subcutaneous adipocytes are crucial for mammary gland epithelial development during pregnancy. Our and others' previous data have suggested that adipo-epithelial transdifferentiation could play a key role in the mammary gland alveolar development. In this study, we tested whether adipo-epithelial transdifferentiation occurs in vitro.

The Adipose Organ Is a Unitary Structure in Mice and Humans.

Obesity is the fifth leading cause of death worldwide. In mice and humans with obesity, the adipose organ undergoes remarkable morpho-functional alterations. The comprehension of the adipose organ function and organization is of paramount importance to understand its pathology and formulate future therapeutic strategies.

A large proportion of mediastinal and perirenal visceral fat of Siberian adult people is formed by UCP1 immunoreactive multilocular and paucilocular adipocytes.

Many deleterious consequences for health of excessive fat accumulation are due to visceral fat. Browning of visceral fat is mainly cold dependent and has been proposed as a possible tool for future therapies of obesity and related disorders. In this paper, we studied the composition of mediastinal and perirenal visceral fat, collected at necropsy, of human adults that lived in Siberia, one of the coldest regions of the earth.

pSBVB: A Versatile Simulation Tool To Evaluate Genomic Selection in Polyploid Species.

Genomic Selection (GS) is the procedure whereby molecular information is used to predict complex phenotypes and it is standard in many animal and plant breeding schemes. However, only a small number of studies have been reported in horticultural crops, and in polyploid species in particular. In this paper, we have developed a versatile forward simulation tool, called polyploid Sequence Based Virtual Breeding (pSBVB), to evaluate GS strategies in polyploids; pSBVB is an efficient gene dropping software that can simulate any number of complex phenotypes, allowing a very flexible modeling of phenotypes suited to polyploids.

Polarized Ends of Human Macula Densa Cells: Ultrastructural Investigation and Morphofunctional Correlations.

The morphology of the kidney macula densa (MD) has extensively been investigated in animals, whereas human studies are scanty. We studied the fine structure of human MD cells focusing on their apical and basal ends and correlating structure and function. The MD region was examined by transmission electron microscopy in six renal biopsies from patients with kidney disease.

Evaluation of the biofilm forming ability and its associated genes in Staphylococcus species isolates from bovine mastitis in Argentinean dairy farms.

Staphylococcus aureus and coagulase-negative staphylococci (CNS) are important causes of intramammary infection in dairy cattle, and their ability to produce biofilm is considered an important virulence property in the pathogenesis of mastitis. However, the published date on mechanisms and factors involved in infection persistence in the mammary gland remains unclear. The aim of this study was to investigate whether the main Staphylococcus species involved in bovine intramammary infections possess specific characteristics that promote colonization of the udder.

Human White Adipocytes Convert Into "Rainbow" Adipocytes In Vitro.

White adipocytes are plastic cells able to reversibly transdifferentiate into brown adipocytes and into epithelial glandular cells under physiologic stimuli in vivo. These plastic properties could be used in future for regenerative medicine, but are incompletely explored in their details. Here, we focused on plastic properties of human mature adipocytes (MA) combining gene expression profile through microarray analysis with morphologic data obtained by electron and time lapse microscopy.

Omental adipose tissue fibrosis and insulin resistance in severe obesity.

Background/objectives: The unresolved chronic inflammation of white adipose tissue (WAT) in obesity leads to interstitial deposition of fibrogenic proteins as reparative process. The contribution of omental adipose tissue (oWAT) fibrosis to obesity-related complications remains controversial. The aim of our study was to investigate whether oWAT fibrosis may be related to insulin resistance in severely obese population.

Molecular and functional characterization of human bone marrow adipocytes.

Adipocytes are a cell population largely located in the human bone marrow cavity. In this specific microenvironment where adipocytes can interact with a variety of different cells, the role of fat is mainly unknown. To our knowledge, this report is the first to characterize mature adipocytes isolated from human bone marrow (BM-A) molecularly and functionally to better understand their roles into the hematopoietic microenvironment.

Foetal bovine intermuscular adipose tissue exhibits histological and metabolic features of brown and white adipocytes during the last third of pregnancy.

This study reports the metabolic and morphological characteristics of bovine intermuscular adipose tissue (AT) throughout foetal growth. Our hypothesis was that the histological and molecular features of intermuscular AT would be different from those previously reported for foetal perirenal AT, based on its anatomical location near the muscle and the recent identification of two distinct adipocyte precursors in mouse AT depending on their locations. To address this question, intermuscular AT was sampled from Charolais and Blond d'Aquitaine foetuses at 180, 210 and 260 days post conception (dpc).

Human dedifferentiated adipocytes show similar properties to bone marrow-derived mesenchymal stem cells.

Mature adipocytes are generally considered terminally differentiated because they have lost their proliferative abilities. Here, we studied the gene expression and functional properties of mature adipocytes isolated from human omental and subcutaneous fat tissues. We also focused on dedifferentiated adipocytes in culture and their morphologies and functional changes with respect to mature adipocytes, stromal-vascular fraction (SVF)-derived mesenchymal stem cells (MSCs) and bone marrow (BM)-derived MSCs.

The vascular endothelium of the adipose tissue gives rise to both white and brown fat cells.

Adipose tissue expansion involves the enlargement of existing adipocytes, the formation of new cells from committed preadipocytes, and the coordinated development of the tissue vascular network. Here we find that murine endothelial cells (ECs) of classic white and brown fat depots share ultrastructural characteristics with pericytes, which are pluripotent and can potentially give rise to preadipocytes. Lineage tracing experiments using the VE-cadherin promoter reveal localization of reporter genes in ECs and also in preadipocytes and adipocytes of white and brown fat depots.

The adipose organ of obesity-prone C57BL/6J mice is composed of mixed white and brown adipocytes.

White and brown adipocytes are believed to occupy different sites in the body. We studied the anatomical features and quantitative histology of the fat depots in obesity and type 2 diabetes-prone C57BL/6J mice acclimated to warm or cold temperatures. Most of the fat tissue was contained in depots with discrete anatomical features, and most depots contained both white and brown adipocytes.

A PGC1-α-dependent myokine that drives brown-fat-like development of white fat and thermogenesis.

Exercise benefits a variety of organ systems in mammals, and some of the best-recognized effects of exercise on muscle are mediated by the transcriptional co-activator PPAR-γ co-activator-1 α (PGC1-α). Here we show in mouse that PGC1-α expression in muscle stimulates an increase in expression of FNDC5, a membrane protein that is cleaved and secreted as a newly identified hormone, irisin. Irisin acts on white adipose cells in culture and in vivo to stimulate UCP1 expression and a broad program of brown-fat-like development.

Cellular and molecular large-scale features of fetal adipose tissue: is bovine perirenal adipose tissue brown?

Epidemiological and fetal programming studies point to the role of fetal growth in adult adipose tissue (AT) mass in large mammals. Despite the incidence of fetal AT growth for human health and animal production outcomes, there is still a lack of relevant studies. We determined the cellular and large-scale-molecular features of bovine fetal perirenal AT sampled at 110, 180, 210, and 260 days post-conception (dpc) with the aim of identifying key cellular and molecular events in AT growth.

[Family caregivers--waiting for visibility].

A course with the family caregivers of patients with Alzheimer disease, multiple sclerosis, Parkinson disease and other chronic severe illnesses was the occasion for reflecting on caregivers and educational needs. The usual uneven relationship of teachers (doctors and nurses) and learners (usually caregivers) was paralleled and the dialogue and the exchange of experiences was conducted at the same level. The course, aimed at providing practical help (teach caregivers how to care for their relative) but also at promoting a reflection on the caregiving experience, was held in two editions with the participation of more than 100 caregivers.

Adipocyte metabolism and cellularity are related to differences in adipose tissue maturity between Holstein and Charolais or Blond d'Aquitaine fetuses.

This paper reports the metabolic and morphological characteristics of bovine adipose tissue (AT) at end of fetal life and its variability with breed and anatomical site of AT. Our hypothesis was that, in cattle, end-of-fetal-life differences in adipocyte number, size, and histology may account for differences in AT maturity. To address this question, perirenal and intermuscular AT were sampled from Charolais, Blond d'Aquitaine, and Holstein fetuses at 260 d postconception.

In vivo physiological transdifferentiation of adult adipose cells.

Grafts of adipose tissue from adult Rosa26 mice from different sites of the body, irrespective of the sex of the donor, share with the mammary fat the property of giving rise to milk-secreting epithelial cells when exposed to the microenvironment of the mammary gland in pregnant and lactating females. To rule out the possibility that the labeled mammary glandular tissue was derived from stem cells associated with the stroma vascular part of the grafts, we injected into the mammary gland a pure suspension of adipocytes obtained by treating a fragment of adipose tissue with collagenase. X-gal-positive cells were inserted into the alveoli of the native gland, and electron microscopy showed that the labeled cells had transformed into milk-secreting glandular cells.

The presence of UCP1 demonstrates that metabolically active adipose tissue in the neck of adult humans truly represents brown adipose tissue.

Classically, adult humans have been considered not to possess active brown adipose tissue (BAT). However, positron-emission-tomography has shown fluorodeoxyglucose uptake that is distributed in such a way (e.g.

Effects of 6-month daily supplementation with oral beta-carotene in combination or not with benzo[a]pyrene on cell-cycle markers in the lung of ferrets.

Epidemiological studies have demonstrated that people who eat more fruits and vegetables (rich in carotenoids) and people who have higher serum beta-carotene (BC) levels have a lower risk of cancer, particularly lung cancer. However, the two main human intervention studies of BC supplementation (the ATBC and the CARET trials) revealed an increased risk of lung cancer among smokers and asbestos workers. Previous studies carried out in the ferret have reported that BC effects are related to dose.

Morphology of ferret subcutaneous adipose tissue after 6-month daily supplementation with oral beta-carotene.

Adipose tissue is an important retinoid depot and retinoids are known to influence white and brown adipocyte metabolism. Identifying nutrients that can affect the biological activity of the adipose organ would be of great medical interest in the light of the current obesity epidemic and related disorders in developed countries. The vast majority of mammal studies of chronic administration of oral beta-carotene have used murine models, while few have employed mammals exhibiting uptake and processing of intestinal beta-carotene similar to those of humans.

Reversible transdifferentiation of secretory epithelial cells into adipocytes in the mammary gland.

Mammalian breast adipose tissue is replaced by a milk-secreting gland during pregnancy; the reverse process takes place upon interruption of lactation. Morphological and bromodeoxyuridine studies provide indirect evidence that mouse mammary adipocytes transform into secretory epithelial cells during pregnancy and revert to adipocytes after lactation. By using the Cre-loxP recombination system we show that the mammary gland of whey acidic protein (WAP)-Cre/R26R mice, in which secretory epithelial cells express the lacZ gene during pregnancy, contains labeled adipocytes during involution.

Sibutramine-dependent brown fat activation in rats: an immunohistochemical study.

Objectives: To evaluate morphological aspects and immunohistochemical markers of brown adipose tissue (BAT) activation following chronic treatment with sibutramine, a novel anti-obesity drug which increases thermogenesis and energy expenditure in mammals, and to establish whether chronic sibutramine treatment induces recruitment of BAT in white adipose tissue (WAT) depots.

Design: Adult rats were administered 7 mg/kg/day oral sibutramine for 4 weeks. Body weight was monitored daily.

Expression of the uncoupling protein 1 from the aP2 gene promoter stimulates mitochondrial biogenesis in unilocular adipocytes in vivo.

Mitochondrial uncoupling protein 1 (UCP1) is a specific marker of multilocular brown adipocytes. Ectopic UCP1 in white fat of aP2-Ucp1 mice mitigates development of obesity by both, increasing energy expenditure and decreasing in situ lipogenesis. In order to further analyse consequences of respiratory uncoupling in white fat, the effects of the ectopic UCP1 on the morphology of adipocytes and biogenesis of mitochondria in these cells were studied.

CL316,243 and cold stress induce heterogeneous expression of UCP1 mRNA and protein in rodent brown adipocytes.

Uncoupling protein 1 (UCP1), the mammalian thermogenic mitochondrial protein, is found only in brown adipocytes, but its expression by immunohistochemistry is not homogeneous. Here we present evidence that the non-homogeneous pattern of immunostaining for UCP1 (referred to as the "Harlequin phenomenon") is particularly evident after acute and chronic cold (4C) stimulus and after administration of a specific beta(3)-adrenoceptor agonist (CL316,243). Accordingly, mRNA in situ expression confirmed the UCP1 non-homogeneous pattern of gene activation under conditions of adrenergic stimulus.