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Na Li,
Xiaolong Hu,
Yang Liu,
Yaojun Wang,
Yunchuan Wang, Jiaqi Liu,
Weixia Cai,
Xiaozhi Bai,
Xiongxiang Zhu,
Juntao Han,
Dahai Hu
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ABSTRACT: Burn wound-related sepsis is associated with the development of systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). This study is aimed at investigating the development and progression of SIS and MODS in a mouse model of skin burn sepsis. C57BL/6J mice were randomly divided into the sham, burn, Pseudomonas and burn/Pseudomonas groups. The back skin of the sham, burn and burn/Pseudomonas groups was burned about 10% of total area with using 37°C or 98°C water for 8 sec, respectively, followed by inoculating with Pseudomonas aeruginosa. The Pseudomonas group was infected with Pseudomonas aeruginosa without burn injury. Their body weights, mortality, organ histology and function as well as systemic inflammation were measured longitudinally. The burn/Pseudomonas mice lost more body weights than other groups and had a significantly higher mortality rate (p < 0.05). The burn/Pseudomonas mice exhibited significantly higher levels of bacterial loads in different organs and serum endotoxin, IL-β, IL-6, TNFα and C reactive protein (CRP) than that in other groups (p < 0.05). The burn/Pseudomonas mice also displayed more severe liver, lung and kidney tissue damage and impaired organ functions, particularly at 72 hours post inoculation than that in the burn and Pseudomonas groups of mice. Our data indicate that burn and Pseudomonas aeruginosa infection induced severe sepsis and rapidly progressed into SIRS and MODS in mice.
Shock (Augusta, Ga.) 05/2013; · 2.87 Impact Factor
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Xiaolong Hu,
Hongtao Wang, Jiaqi Liu,
Xiaobing Fang,
Ke Tao,
Yaojun Wang,
Na Li,
Jihong Shi,
Yunchuan Wang,
Peng Ji,
Weixia Cai,
Xiaozhi Bai,
Xiongxiang Zhu,
Juntao Han,
Dahai Hu
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ABSTRACT: CCN2 plays an important role in the pathogenesis of hypertrophic scars (HTSs). Although CCN2 is involved in many fibroproliferative events, the CCN2 induction signaling pathway in HTSs is yet to be elucidated. Here, we first investigated the effect of the mitogen-activated protein kinases (MAPKs) on CCN2-induced α-smooth muscle actin (α-SMA) and collagen I expression in human HTS fibroblasts (HTSFs). Then, we established HTSs in a rabbit ear model and determined the effect of MAPKs on the pathogenesis of HTSs. MAPK pathways were activated by CCN2 in HTSFs. Extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) inhibitors significantly inhibited CCN2-induced expression of α-SMA and collagen I in HTSFs. In the rabbit ear model of the HTS, JNK and ERK inhibitors significantly improved the architecture of the rabbit ear scar and reduced scar formation on the rabbit ear. Our results indicate that ERK and JNK mediate collagen I expression and scarring of the rabbit ear, and may be considered for specific drug therapy targets for HTSs.
Archives for Dermatological Research 03/2013; · 2.28 Impact Factor
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ABSTRACT: Vascularized bone marrow transplantation (VBMT) is widely accepted as an efficient means of establishing chimerism and inducing tolerance. However, the mechanism underlying is poorly understood. Recently, regulatory T cells (Tregs) have been shown to play an important role in regulating immune responses to allogeneic antigens. In this study, we explored the role of Tregs in the induction of tolerance in an allogeneic hind limb transplantation model.
Forty-eight Lewis rats were divided into 6 groups. They received isografts and allografts from Brown-Norway hind limbs. Recipients in groups 1 and 2 received isografts and those in the other groups received allografts. The bone components of donor limbs were kept intact in groups 1, 3, and 5 but removed before transplantation into groups 2, 4, and 6. Tapered cyclosporin A (CsA) was administered to recipients in groups 5 and 6 after transplantation. During the 100-day observation period, all isografts survived, but the allografts in groups 3 and 4 were rejected within 8 to 12 days. CsA-treated intact allografts survived rejection-free for more than 100 days, and CsA-treated allografts lacking bone elements were rejected within 2 months. Stable peripheral chimerism and myeloid chimerism were observed in group 5. Declining peripheral chimerism and a lack of myeloid chimerism were observed in group 6. Donor-specific Tregs were exclusively detected in both peripheral blood and in the spleens of long-term recipient rats in group 5, with an increased FoxP3 mRNA expression in the allografts. This was further demonstrated to be responsible for donor-specific hyporeactivity by in vitro one-way mixed lymphocyte reaction (MLR).
Bone components in the allogeneic hind limbs can induce myeloid chimerism and donor-specific Tregs may be essential to tolerance induction. The bone-removal hind limb model may be a suitable counterpart to the induction of tolerance in the study of limb transplantation.
PLoS ONE 01/2012; 7(8):e43825. · 4.09 Impact Factor
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ABSTRACT: Fibroblast-to-myofibroblast transition is a key event during wound healing and hypertrophic scar formation. Previous studies suggested Wnt/β-catenin signaling might be involved in the wound healing. However, its specific role in skin fibroblast-to-myofibroblast transition remains unclear.
To investigate the specific role of β-catenin during the transforming growth factor-β1 induced normal skin myofibroblasts transition.
By real-time quantitative polymerase chain reaction, Western-blot and immunocytochemistry, the activation of Wnt/β-catenin pathway in cultured human normal skin fibroblasts during TGF-β1 induced fibroblast-to-myofibroblast transition was investigated. The effects of β-catenin on myofibroblasts transition were also investigated when SB-216763, over-expression and siRNA of β-catenin were utilized. In addition, fibroblasts populated collagen lattices contraction assays were conducted to examine the effects of β-catenin on the contractility of the fibroblasts induced by TGF-β1. Furthermore, the effects of β-catenin on the expression of α-smooth muscle actin and collagen types I and III in hypertrophic scar derived fibroblasts were studied.
The expression of Wnts mRNA and β-catenin protein was up-regulated by TGF-β1 stimulation during the myofibroblasts transition. Both of SB-216763 and β-catenin over-expression was paralleled with decreased expression of α-smooth muscle actin, collagen types I and III, while siRNA targeting β-catenin leads to up-regulation of α-smooth muscle actin, collagen types I and III. The increased contractility and α-smooth muscle actin expression of the fibroblasts in the collagen lattices induced by TGF-β1 was inhibited by SB-216763. In addition, the expression levels of α-smooth muscle actin, collagen types I and III in hypertrophic scar derived fibroblasts were also down-regulated by SB-216763.
Specifically in normal skin fibroblasts, β-catenin might be involved in the myofibroblasts transition and negatively regulate the TGF-β1-induced myofibroblast transition.
Journal of dermatological science 01/2012; 65(1):38-49. · 3.71 Impact Factor
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ABSTRACT: Transplantation of allogeneic donor bone marrow (BM) into sufficiently conditioned recipients is an effective approach to induce immune tolerance as assessed by mixed chimerism. However, this approach is hampered by the lack of feasible protocols devoid of cytoreductive conditioning. We investigated whether mixed chimerism could be established by intra-bone marrow-bone marrow transplantation (IBM-BMT) combined with bone marrow-derived mesenchymal stem cells (BMSCs) treatment without additional cytoreductive conditioning.
The recipient mice (C57BL/6) accepted BMSCs from donor mice (Balb/c) through daily tail vein injection for 4 d followed by IBM-BMT immediately. Full-thickness skin grafts from donor mice as well as from the third party mice (ICR) were transplanted to the dorsum of the recipient mice after the combined IBM-BMT with BMSCs treatment. The immune tolerance was assessed by the survival time of skin allografts. The establishment of mixed chimerism and cytokine expression profile in recipient peripheral blood were determined by flow cytometry and enzyme-linked immunosorbent assay, respectively.
IBM-BMT combined with BMSCs treatment led to stable mixed chimerism and donor-specific skin graft tolerance. The flow cytometry analysis revealed that recipient mice developed 20%-25% chimerism levels among the myeloid lineage. The skin allografts survived more than 1 y and the hair re-grew normally on the grafts. Cytokine profile showed that IBM-BMT combined with BMSCs treatment prolonged humoral tolerance in recipient chimeras.
Our results demonstrate that donor specific immune tolerance can be effectively induced by IBM-BMT combined with BMSCs treatment without any additional cytoreductive recipient treatment. This approach provides a promising allograft transplantation strategy when the donor bone marrow is available.
Journal of Surgical Research 07/2011; 171(1):e123-31. · 2.25 Impact Factor
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ABSTRACT: To isolate and culture adipose-derived stem cells (ADSCs), and to study the effects of the conditioned medium of ADSCs (ADSC-CM) treated with insulin on HaCaT cells.
ADSCs were isolated from adipose tissue donated by the patient receiving abdominal surgery and were cultured. The concentration of ADSCs at passage 3 was adjusted to 5 x 10(4) cells/mL. The cells were divided into 2 groups: group A in which the cells were incubated in 1 x 10(-7) mol/L insulin for 3 days, and group B in which the cells were not treated with insulin. ADSC-CM in each group was collected 3 days after culture, then levels of VEGF and hepatocyte growth factor (HGF). HaCaT cells were cultured and the cells at passage 4 were divided into 4 groups: group A1, 0.5 mL 2% FBS and 0.5 mL ADSC-CM from group A; group B1, 0.5 mL 2% FBS and 0.5 mL ADSC-CM from group B; group C1, 1 mL 2% FBS of 1 x 10(-7) mol/L insulin; group D1, 1 mL 2% FBS. Proliferation of HaCaT cells was detected by MTT method 3 days after culture, apoptosis rate of HaCaT cells was measured by Annexin V-FITC double staining 12 hours after culture, and the migration ability was measured by in vitro wound-healing assay 0, 12, 24, 36 and 48 hours after culture.
The level of VEGF in groups A and B was (643.28 +/- 63.57) and (286.52 +/- 46.68) pg/mL, respectively, and the level of HGF in groups A and B was (929.95 +/- 67.52) and (576.61 +/- 84.29) pg/mL, respectively, suggesting differences were significant between two groups (P < 0.05). Cell proliferation detection showed the absorbance value of HaCaT cells in group A1, B1, C1 and D1 was 0.881 +/- 0.039, 0.804 +/- 0.041, 0.663 +/- 0.027 and 0.652 +/- 0.042, respectively, suggesting there was significant difference between groups A1 and B1 and groups C1 and D1 (P < 0.01), group A1 was significantly higher than group B1 (P < 0.05). The apoptosis rate of HaCaT cells in groups A1, B1, C1 and D1 was 5.23% +/- 1.98%, 8.82% +/- 2.59%, 31.70% +/- 8.85% and 29.60% +/- 8.41%, respectively, indicating there was significant difference between groups A1 and B1 and groups C1 and D1 (P < 0.05), group B1 was significantly higher than group A1 (P < 0.05). The migration distance of HaCaT cells in groups A1, B1, C1 and D1 at 36 hours was (0.184 6 +/- 0.019 2), (0.159 8 +/- 0.029 4), (0.059 2 +/- 0.017 6) and (0.058 2 +/- 0.012 3) mm, respectively, whereas at 48 hours, it was (0.231 8 +/- 0.1740), (0.205 1 +/- 0.012 1), (0.079 2 +/- 0.008 1) and (0.078 4 +/- 0.011 7) mm, respectively, suggesting there were significant differences between groups A1 and B1 and groups C1 and D1 at 36 and 48 hours (P < 0.01), group A1 was significantly higher than group B1 (P < 0.05) at 36 and 48 hours, no significant difference was evident at other time points (P > 0.05).
ADSCs treated with insulin can significantly promote the proliferation and the migration of HaCaT cells and inhibit their apoptosis.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 06/2009; 23(6):727-31.
