Future application of hair follicle stem cells: capable in differentiation into sweat gland cells.

Background: Sweat glands (SGs) can not regenerate after complete destruction in the severe skin injury, so it is important to find a ideal stem cell source in order to regenerate functional SGs. Hair follicle stem cells (HFSCs) possess the obvious properties of the adult stem cells, which are multipotent and easily accessible. In this research, we attempted to direct the HFSCs suffered from the sweat gland cells (SGCs) special differentiation by a co-operative coculture system in vitro.

Bone marrow-derived mesenchymal stem cell attenuates skin fibrosis development in mice.

Recent studies showed that mesenchymal stem cell (MSC) transplantation significantly alleviated tissue fibrosis; however, little is known about the efficacy on attenuating cutaneous scar formation. In this study, we established a dermal fibrosis model induced by bleomycin and evaluated the benefit of bone marrow-derived mesenchymal stem cells (BM-MSCs) on skin fibrosis development. Tracing assay of green fluorescent protein (GFP(+) )BM-MSCs showed that the cells disappeared gradually within 24 hours upon administration, which hinted the action of BM-MSCs in vivo was exerted in the initial phase of repair in this model.

Effect of Poloxamer 188 on deepening of deep second-degree burn wounds in the early stage.

Objective: To discuss the effect of Poloxamer 188 (P188) on deepening of deep second-degree burn wounds in the early stage after burn.

Methods: We divided Wistar rats with deep second-degree burn wounds on the backs thereof into two groups, then intravenously injected P188 for the treatment group and intravenously injecting physiological saline for the control group, detecting the activity of Na(+)-K(+)-adenosine triphosphatase (Na(+)-K(+)-ATPase), myeloperoxidase (MPO) and the content of malonaldehyde (MDA) and succinic dehydrogenase (SDH) in the burn wound, and showing the degree of necrosis in the wound by haematoxylin-eosin (HE) and proliferating cell nuclear antigen (PCNA) immunohistochemical staining.

Results: In the control group and treatment group, the activity of SDH and Na(+)-K(+)-ATPase dropped to the lowest point 24 h after the burn took place, and then increased gradually, but was still far lower than the normal level at the furthest time point.

Wnt/β-catenin signaling is critical for dedifferentiation of aged epidermal cells in vivo and in vitro.

Aged epidermal cells have the capacity to dedifferentiate into stem cell-like cells. However, the signals that regulate the dedifferentiation of aged epidermal cells remain unclear. Here, we provide evidence that Wnt/β-catenin is critical for aged epidermal cell dedifferentiation in vivo and in vitro.

Transplantation of human bone marrow-derived mesenchymal stem cells transfected with ectodysplasin for regeneration of sweat glands.

Background: Patients with severe full-thickness burn injury suffer from their inability to maintain body temperature through perspiration because the complete destructed sweat glands can not be regenerated. Bone marrow-derived mesenchymal stem cells (BM-MSCs) represent an ideal stem-cell source for cell therapy because of their easy purification and multipotency. In this study, we attempted to induce human BM-MSCs to differentiate into sweat gland cells for sweat gland regeneration through ectodysplasin (EDA) gene transfection.

[Effects of estrogen on proliferation and migration of human epidermal stem cells in vitro].

Objective: In vivo, the microenvironment of epidermal stem cells (ESCs) is complex, and estrogen might be involved in the micro environment. To investigate the biological effects of estrogen on the proliferation and migration of ESCs in vitro.

Methods: hESCs were isolated from normal human foreskin and cultured.

Calcitonin gene-related peptide regulates the growth of epidermal stem cells in vitro.

Epidermal stem cells are characterized as slow-cycling, multi-potent, self-renewing cells that not only maintain somatic homeostasis, but also participate in tissue regeneration and repair. Various factors can influence the growth of epidermal stem cells. Recently, dysregulation of epidermal stem cells has been reported to be involved in epidermal hyperproliferative diseases and skin tumors.

[A new way for isolation and cultivation of sweat gland ductal cells from human split-thickness skin in vitro].

Objective: To explore a new method of isolation and culture of eccrine sweat gland ductal cells from human split-thickness skin graft in vitro.

Methods: Human split-thickness skin graft which was presented by volunteer (n = 10) was digested with type II collagenase, and then sweat gland duct were isolated from the split-thickness skin graft, primary cultures were incubated at 37 degrees C in humidified atmosphere of 5% CO2, 95% O2. The cultured eccrine sweat gland ductal cells were identified by analysis CEA, CK8, CK18, CK19 antigens expression with flow cytometry, RT-PCR and Western Blot, and by detecting the electrophysiology with whole cell patch clamp technology.

Regeneration of functional sweat gland-like structures by transplanted differentiated bone marrow mesenchymal stem cells.

Regeneration of sweat glands after deep burns has been an unsolved problem. Owing to lack of perspiration, survivors of an extensive deep burn injury are leading a miserable life in sultry months. It was our contemplation to solve this problem by inducing bone marrow mesenchymal stem cells (MSCs) to acquire the phenotype of sweat gland cells in vitro.

Dedifferentiation derived cells exhibit phenotypic and functional characteristics of epidermal stem cells.

Differentiated epidermal cells can dedifferentiate into stem cells or stem cell-like cells in vivo. In this study, we report the isolation and characterization of dedifferentiation-derived cells. Epidermal sheets eliminated of basal stem cells were transplanted onto the skin wounds in 47 nude athymic (BALB/c-nu/nu) mice.

Migration of bone marrow-derived mesenchymal stem cells induced by tumor necrosis factor-alpha and its possible role in wound healing.

We aimed to investigate the effect of tumor necrosis factor-alpha (TNF-alpha) on the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in the migration ability of mesenchymal stem cells (MSCs) in the context of wound healing. We also explored the role of p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (ERK) signaling pathways in the migration of MSCs. MSCs were isolated from the bone marrow and cultured.

[Promotive effect of adipose-derived stem cells on the wound model of human epidermal keratinocytes in vitro].

Objective: To investigate the migrating effect of adipose derived stem cells (ADSCs) on the wound model of human epidermal keratinocyte (HEKa).

Methods: Rat ADSCs (rADSCs) were isolated and cultured (n = 10), rADSCs were direct co-cultured with HEKa cells in experiment group (experimental group, n = 10). In the control groups, rADSCs were indirect co-cultured with HEKa cells in transwell chamber (indirect group, n = 8), or HEKa was cultured alone (single group, n = 8).

Research of PDGF-BB gel on the wound healing of diabetic rats and its pharmacodynamics.

Background: One of the leading causes of impaired wound healing is diabetes mellitus. In diabetic patients, a minor skin wound often leads to serious complications. Many experiments had demonstrated that the expression of platelet-derived growth factor (PDGF) and its receptor was decreased in wounds of healing-impaired diabetic mice, indicating that a certain expression level of PDGF is essential for normal repair.

In vivo dedifferentiation of human epidermal cells.

Consistent with our previous study, we herein offer further evidence to demonstrate the dedifferentiation of differentiating epidermal cells into stem cells or stem cells -like in vivo. The epidermal sheets eliminated of basal cells were labeled with 6-diamidino-2-phenylindole (DAPI), and then were transplanted onto the full-thickness skin wounds nude mice. Immunohistochemical examination of the survival sheets showed that some cells were positive for both DAPI and either cytokeratins (CK19, CK14) or beta1 integrin in spinous and granular layers at day 7 after transplantation.

[Chemotactic effects of burn rat serum on mesenchymal stem cells derived from different sources].

Objective: To isolate and culture mesenchymal stem cells ( MSC) from different sources and to investigate the chemotactic effects of burn rat serum on MSC derived from different sources.

Methods: Seventy-two Wistar rats were randomly divided into burn( n = 36, with 30% TBSA full-thickness burns on the back) and sham burn (n = 36, without burns) groups. Bone marrow and peripheral blood of the rats in both groups were collected to isolate and culture MSC.

[Identification and cell phenotype transdifferentiation of adipose-derived stem cells].

Objective: To investigate the transdifferentiation of the ADSCs to epidermal cells.

Methods: ADSCs were isolated and cultured from rat adipose tissue by digestion of enzyme. ADSCs was identified by immunocytochemistry and flow cytometry.

Differential expression of matrix metalloproteinases and tissue-derived inhibitors of metalloproteinase in fetal and adult skins.

Matrix metalloproteinases and their tissue-derived inhibitors determine the architecture of the extracellular matrix. In early gestation, the amount and organization of extracellular matrix may be associated with scarless repair of fetal skin wounds. To elucidate the part of the mechanism(s) underlying the phenotypic transition from scarless to scar-forming healing observed during fetal gestation, the ontogeny of matrix metalloproteinase-2, -9, -14 and their tissue inhibitors was characterized in non-wounded fetal human skin with different gestational ages from 13 to 33 weeks and adult skin using reverse transcriptase-polymerase chain reaction, immunohistochemical staining and western blot protocols.

Non-mitogenic acidic fibroblast growth factor reduces intestinal dysfunction induced by ischemia and reperfusion injury in rats.

Background: Acidic fibroblast growth factor (aFGF) has potentially therapeutic uses in some diseases, but the mitogenic activity of aFGF has been found to contribute to several human pathologies, so the extensive applications of wild-type aFGF have been limited. The purpose of the present study was to explore the effects and mechanisms of wild-type (aFGF) and non-mitogenic aFGF on gut ischemia-reperfusion injury in rats.

Methods: Rat intestinal ischemia-reperfusion injury (I/R) was produced by clamping the superior mesenteric artery (SMA) for 45 min followed by reperfusion.

Recombinant human platelet-derived growth factor enhanced dermal wound healing by a pathway involving ERK and c-fos in diabetic rats.

Background: Platelet-derived growth factor (PDGF) has been shown to promote dermal wound healing, however, the molecular mechanisms responsible for are not fully understood.

Objective: The present study was undertaken to investigate the possible signaling mechanisms by which PDGF improved healing of cutaneous wound in diabetic rats.

Methods: Four full-thickness skin wounds were created on the dorsum of Wistar diabetic rats.

Profiling of genes differentially expressed in a rat of early and later gestational ages with high-density oligonucleotide DNA array.

The early gestational fetus heals dermal wounds rapidly and scarlessly. This phenomenon appears to be intrinsic to fetal skin and is probably modulated by interplay of many genes. We ventured to study differences in gene expression between earlier gestational skin (EGS) and later gestational skin (LGS) with the aid of high-density oligonucleotide DNA array to explore the molecular mechanism underlying scarless healing.

Recombinant human platelet-derived growth factor enhances repair of cutaneous full-thickness excision by increasing the phosphorylation of extracellular signal-regulated kinase in diabetic rat.

Objective: To investigate the possible signaling mechanisms by which recombinant human platelet-derived growth factor (rhPDGF) accelerated healing of cutaneous wound in diabetic rats.

Methods: Four full-thickness skin wounds were incised in the back of 26 male Wistar diabetic rats. The wounded rats were divided into 3 groups (7 or 8 rats each group).

Adult bone-marrow-derived mesenchymal stem cells contribute to wound healing of skin appendages.

Adult bone-marrow-derived mesenchymal stem cells (MSCs) are well-established as having the capacity to differentiate into cells with mesodermal, ectodermal, and endodermal characteristics and can leave their niche to home toward and engraft within foreign tissues. To investigate whether adult MSCs contribute to the repair of skin appendages after injury, BrdU-labeled MSCs were co-cultured with heat-shocked confluent sweat gland cells (SGCs) in vitro and later intravenously injected into full-thickness skin wounds in rats. When adult MSCs were co-cultured with heat-shocked SGCs, a subset of adult MSCs differentiated into SGCs, the percentage of differentiation being enhanced by epidermal growth factor and the injured microenviroment, but weakened by PD98059.

[Mechanism of signal transduction of differentiation of mesenchymal stem cells into cytokeratin-expressing epidermoid cells].

Objective: To investigate the role of the signal routes P38, ERK, and Rho in the differentiation of bone marrow mesenchymal stem cells (MSCs) into epidermoid cells.

Methods: (1) MSCs were separated from the bone marrow of Wistar rats by Ficoll-Pague lymphocyte separating medium and proliferated in culture medium. Then the MSCs were immunocytochemically stained to detect the expression of surface antigens.

[Relationship between the proliferation and immunoinduction of epithelial cells and the destruction of hair follicles and sebaceous glands in keloids].

Objective: To investigate the influence of biological behavior of epithelial cells on the hair follicles and sebaceous glands (HFSG) structure in keloids (K).

Methods: The expression of intercellular adhesion molecule (ICAM)-1, D-related human leucocyte antigen (HLA-DR), and cytokeratin (CK) 14 on epithelial cells and the amount of activity T-lymphocytes were detected in specimens of keloid edge and normal skin with immunohistochemical and histological methods.

Results: In comparison with normal skin specimens, epithelial cells were proliferated in K-HFSG presented structural aberration and disintegrate or abnormally to form solid-epithelial island-like structure, and the density of HSFG with hyperplasia and the ageing scar in keloids was apparently decreased.