Platelet-rich plasma respectively reduces and promotes adipogenic and myofibroblastic differentiation of human adipose-derived stromal cells via the TGFβ signalling pathway.

Autologous fat grafting is a gold standard therapy for soft tissue defects, but is hampered by unpredictable postoperative outcomes. Fat graft enrichment with adipose-derived stromal cell (ASCs) was recently reported to enhance graft survival. Platelet-rich plasma (PRP) has also emerged as a biologic scaffold that promotes fat graft viability.

Homeotic and Embryonic Gene Expression in Breast Adipose Tissue and in Adipose Tissues Used as Donor Sites in Plastic Surgery.

Background: Autologous fat grafting has become an essential procedure in breast reconstructive surgery. However, molecular knowledge of different adipose donor sites remains inadequate. Tissue regeneration studies have shown that it is essential to match the Hox code of transplanted cells and host tissues to achieve correct repair.

Brown-like adipose progenitors derived from human induced pluripotent stem cells: Identification of critical pathways governing their adipogenic capacity.

Human induced pluripotent stem cells (hiPSCs) show great promise for obesity treatment as they represent an unlimited source of brown/brite adipose progenitors (BAPs). However, hiPSC-BAPs display a low adipogenic capacity compared to adult-BAPs when maintained in a traditional adipogenic cocktail. The reasons of this feature are unknown and hamper their use both in cell-based therapy and basic research.

IER3 Promotes Expansion of Adipose Progenitor Cells in Response to Changes in Distinct Microenvironmental Effectors.

Adipose tissue expansion is well-orchestrated to fulfill the energy demand. It results from adipocyte hypertrophy and hyperplasia due to adipose progenitor cell (APC) expansion and differentiation. Chronic low grade inflammation and hypoxia take place in obese adipose tissue microenvironment.

Characterization of human knee and chin adipose-derived stromal cells.

Animal study findings have revealed that individual fat depots are not functionally equivalent and have different embryonic origins depending on the anatomic location. Mouse bone regeneration studies have also shown that it is essential to match the Hox code of transplanted cells and host tissues to achieve correct repair. However, subcutaneous fat depots from any donor site are often used in autologous fat grafting.

Browning of white adipose cells by intermediate metabolites: an adaptive mechanism to alleviate redox pressure.

The presence of brown adipose tissue (BAT) in human adults opens attractive perspectives to treat metabolic disorders. Indeed, BAT dissipates energy as heat via uncoupling protein (UCP)1. Brown adipocytes are located in specific deposits or can emerge among white fat through the so-called browning process.

Differentiation of human induced pluripotent stem cells into brown and white adipocytes: role of Pax3.

Identification of molecular mechanisms involved in generation of different types of adipocytes is progressing substantially in mice. However, much less is known regarding characterization of brown (BAP) and white adipocyte progenitors (WAPs) in humans, highlighting the need for an in vitro model of human adipocyte development. Here, we report a procedure to selectively derive BAP and WAPs from human-induced pluripotent stem cells.

Expression of cell surface markers during self-renewal and differentiation of human adipose-derived stem cells.

Human adipose-derived stem cell populations express cell surface markers such as CD105, CD73, CD146 and CD140a/PDFGRα. However, it was unclear whether these markers could discriminate subpopulations of undifferentiated cells and whether the expression of these markers is modulated during differentiation. To address this issue, we analysed the immunophenotype of cultured human multipotent adipose derived stem (hMADS) cell populations at different adipocyte differentiation steps.

Engraftment of human adipose derived stem cells delivered in a hyaluronic acid preparation in mice.

Purpose: To evaluate the implant of human adipose derived stem cells (ADSC) delivered in hyaluronic acid gel (HA), injected in the subcutaneous of athymic mice.

Methods: Control implants -HA plus culture media was injected in the subcutaneous of the left sub scapular area of 12 athymic mice. ADSC implants: HA plus ADSC suspended in culture media was injected in the subcutaneous, at the contra lateral area, of the same animals.

TGFbeta family members are key mediators in the induction of myofibroblast phenotype of human adipose tissue progenitor cells by macrophages.

Objective: The present study was undertaken to characterize the remodeling phenotype of human adipose tissue (AT) macrophages (ATM) and to analyze their paracrine effects on AT progenitor cells.

Research Design And Methods: The phenotype of ATM, immunoselected from subcutaneous (Sc) AT originating from subjects with wide range of body mass index and from paired biopsies of Sc and omental (Om) AT from obese subjects, was studied by gene expression analysis in the native and activated states. The paracrine effects of ScATM on the phenotype of human ScAT progenitor cells (CD34(+)CD31(-)) were investigated.

Regulators of human adipose-derived stem cell self-renewal.

Adipose tissue is an alternative source of mesenchymal stem cells and human adipose-derived stem cells (ASCs) display an attractive and substantial therapeutic potential when transplanted in animal models. To this end, an understanding of ASC biology is necessary and the knowledge of mechanisms that maintain ASCs in an undifferentiated state with no loss of differentiation potential during ex vivo expansion represents a crucial step. However, these mechanisms remain to be identified because appropriate human cellular models are scant.

Small RNA sequencing reveals miR-642a-3p as a novel adipocyte-specific microRNA and miR-30 as a key regulator of human adipogenesis.

Background: In severe obesity, as well as in normal development, the growth of adipose tissue is the result of an increase in adipocyte size and numbers, which is underlain by the stimulation of adipogenic differentiation of precursor cells. A better knowledge of the pathways that regulate adipogenesis is therefore essential for an improved understanding of adipose tissue expansion. As microRNAs (miRNAs) have a critical role in many differentiation processes, our study aimed to identify the role of miRNA-mediated gene silencing in the regulation of adipogenic differentiation.

The generation and the manipulation of human multipotent adipose-derived stem cells.

In this chapter, we describe a method to isolate and to expand multipotent adipose-derived stem (hMADS) cells from human adipose tissue. We also describe culture conditions to differentiate them into adipocytes at a high rate. This culture system provides a powerful means for studying the first steps of human adipose cell development and a route for investigating effects of drugs on the biology of adipocytes.

Activin a plays a critical role in proliferation and differentiation of human adipose progenitors.

Objective: Growth of white adipose tissue takes place in normal development and in obesity. A pool of adipose progenitors is responsible for the formation of new adipocytes and for the potential of this tissue to expand in response to chronic energy overload. However, factors controlling self-renewal of human adipose progenitors are largely unknown.

Commitment of mouse embryonic stem cells to the adipocyte lineage requires retinoic acid receptor beta and active GSK3.

Key events leading to terminal differentiation of preadipocytes into adipocytes have been identified in recent years. However, signaling pathways involved in the decision of stem cells to follow the adipogenic lineage have not yet been characterized. We have previously shown that differentiating mouse embryonic stem (mES) cells give rise to functional adipocytes upon an early treatment with retinoic acid (RA).

Effects of GSK3 inhibitors on in vitro expansion and differentiation of human adipose-derived stem cells into adipocytes.

Background: Multipotent stem cells exist within adipose tissue throughout life. An abnormal recruitment of these adipose precursor cells could participate to hyperplasia of adipose tissue observed in severe obesity or to hypoplasia of adipose tissue observed in lipodystrophy. Therefore, pharmacological molecules that control the pool of stem cells in adipose tissue are of great interest.

Differentiation of mouse embryonic stem cells and of human adult stem cells into adipocytes.

The authors describe protocols for culture conditions in which mouse ES cells can be maintained in an undifferentiated state or committed to undergo adipocyte differentiation at a high rate and in a highly reproducible fashion. There is also a protocol for maintaining and differentiating human adult stem cells, isolated form adipose tissue and from bone marrow, into adipocytes. These culture systems provide a powerful means for studying the first step of adipose cell development and a means to investigate effects of drugs on the biology of adipocytes.

Use of differentiating embryonic stem cells in pharmacological studies.

Adipocytes and osteoblasts are derived from a common precursor cell. It has been proposed that the bone loss commonly seen during aging or in the pathology of osteoporosis might be partly caused by a deregulation of the normal balance between osteoblast and adipocyte differentiation. In vitro differentiation of mouse embryonic stem cells toward the adipogenic and the osteogenic lineages provides a powerful system for testing effects of compounds on the developmental switch between adipogenesis and osteogenesis and identification of pharmacological targets.