Research progress and application outlook of paracrine functions of adipose-derived stem cells in facial anti-aging

doi:10.3969/j.issn.2095-4344.2017.05.022

Abstract

Abstract:

BACKGROUND: Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells obtained from adipose tissue, which have paracrine functions, already becoming a focus in anti-aging researching.
OBJECTIVE: To review the research progress and application outlook of ADSCs’ paracrine functions in facial anti-aging.
METHODS: The first author searched the PubMed and CNKI databases using the keywords of “adipose-derived stem cells, paracrine, anti-aging” in English and Chinese, respectively, to retrieve relevant articles published from January 2001 to May 2016. Repetitive articles or those with no originality were eliminated. Totally 176 articles were searched initially, and 66 articles were included in result analysis.
RESULTS AND CONCLUSION: ADSCs have paracrine function, which can secrete various growth factors (e.g., epidermal growth factor, transforming growth factor β, platelet-derived growth factor, vascular endothelial growth factor, collagen and fibronectin) and inflammatory factors (e.g., interferon-γ, interleukin-lβ, interleukin-8, interleukin-9, interleukin-12, interleukin-15, interleukin-17 and tumor necrosis factor-α). These paracrine products of ADSCs have significant effects on anti-aging, such as inhibiting skin aging, whitening skin, assisting lipotransfer, promoting hair regeneration.

中国组织工程研究杂志出版内容重点：干细胞；骨髓干细胞；造血干细胞；脂肪干细胞；肿瘤干细胞；胚胎干细胞；脐带脐血干细胞；干细胞诱导；干细胞分化；组织工程

Key words: Stem Cells, Aging, Tissue Engineering

CLC Number:

R318

Guo Ji-an, Yu Pi-jun, Wang Lu-ping, Shi Ying-ying, Liu Yi, Chen Wei. Research progress and application outlook of paracrine functions of adipose-derived stem cells in facial anti-aging[J]. Chinese Journal of Tissue Engineering Research, 2017, 21(5): 789-794.

Figures/Tables 1

2.1 ADSCs旁分泌的成分 ADSCs可分泌多种生长因子，如表皮生长因子、转化生长因子β、血小板衍生生长因子、血管内皮生长因子、成纤维生长因子、胰岛素样生长因子等，以及胶原蛋白(Ⅰ型、Ⅲ型)和纤维粘连蛋白[18-20]。除此之外，ADSCs还可分泌炎性因子。Blaber等[21]在ADSCs条件培养基中发现27种细胞因子，除了9种生长因子外还含有18种炎性相关因子，包括8种促炎性因子，干扰素γ、白细胞介素1β、白细胞介素8、白细胞介素9、白细胞介素12、白细胞介素15、白细胞介素17和肿瘤坏死因子α；4种抗炎性因子，白细胞介素1Ra、白细胞介素4、白细胞介素10和白细胞介素13；以及6种趋化因子，嗜酸性粒细胞趋化因子、干扰素诱导蛋白10、单核细胞趋化蛋白1、巨噬细胞炎性蛋白和调节活化正常T细胞表达与分泌趋化因子。这些细胞因子按功能可分为5类：①免疫调节作用，如转化生长因子β、肝细胞生长因子、白细胞介素6、前列腺素E2；②血管形成作用，有血管内皮生长因子、肝细胞生长因子、转化生长因子β2、成纤维细胞生长因子2、碱性成纤维细胞生长因子、粒-巨噬细胞集落刺激因子；③中枢神经系统再生作用，胰岛素样生长因子1、脑源性神经营养因子、神经生长因子、胶质细胞源性神经营养因子；④造血支持作用，如肝细胞生长因子、粒-巨噬细胞集落刺激因子、白细胞介素6，7，8，11、肿瘤坏死因子α；⑤其他，脂联素、血管紧张素、组织蛋白酶D、视黄醇结合蛋白、基质细胞衍生因子1等[14， 22-23]。近年来研究发现，ADSCs还可分泌直径20-1 000 nm脂质双层膜包裹结构的亚细胞颗粒，被称为胞外囊泡[24]。胞外囊泡可从干细胞等多种类型细胞中释放，也可被多种细胞摄入，含有与母细胞相似的生物活性物质，包括RNA、DNA、蛋白质、脂质及完整的细胞器如线粒体等[25]。微囊泡可参与调控机体正常生理功能和异常病理过程，被认为是细胞之间通讯的新机制。 2.2 ADSCs旁分泌功能的抗衰老作用众多实验证实，ADSCs分泌的多种细胞因子具有增强细胞增殖和迁移能力，促血管形成及抗细胞凋亡等作用，促进组织功能恢复正常，减少损害，在抗衰老领域有较显著的应用效果[26-28]。 2.2.1 抗皮肤老化皮肤衰老外在表现为肌肤松弛，弹性下降，皱纹增多、加深等；其内在机制是成纤维细胞衰老、受损，数量减少、合成功能下降及异常，导致胶原蛋白含量减少，弹性蛋白变性，最终真皮厚度变薄，皮肤老化[29-30]。紫外线照射引起的光老化是导致皮肤衰老的最主要外因。研究表明，ADSCs所分泌的胰岛素样生长因子、表皮生长因子、转化生长因子β、白细胞介素1和肿瘤坏死因子α，可改善中波紫外线引起的皮肤成纤维细胞损伤，加强成纤维细胞增殖及合成胶原蛋白的能力，其中转化生长因子β在体外实验中刺激成纤维细胞的作用最强[31-32]。将ADSCs用于光老化裸鼠模型，可观察到注射ADSCs部位真皮层厚度和成纤维细胞数量显著增加，成纤维细胞合成胶原蛋白增多，真皮血管生成增加，波紫外线照射导致的皮肤老化外观明显改善[33-34]。Park等[19]将ADSCs条件培养基应用于患者面部皮肤除皱，注射治疗后2个月观察到显著的皮肤质地改善、真皮厚度增加及皱纹淡化。田雅光等[35]对手术联合ADSCs注射进行面部年轻化治疗的患者进行随访，发现接受联合治疗患者的皮肤较单纯手术治疗的更好。 2.2.2 美白皮肤 “肤如凝脂肌如雪”是女性同胞们历来所崇尚美的标准之一，但随着年龄的增长色素沉着使肤色渐渐变暗。皮肤黑色素是由位于表皮基底层的黑素细胞合成的。当黑素细胞受到外界刺激(紫外线、化学刺激、情绪压力等)时会合成黑色素，导致皮肤颜色变深。酪氨酸为黑素细胞制造黑素的主要原料，酪氨酸酶是酪氨酸转变为黑素过程中的主要限速酶。 ADSCs分泌的转化生长因子β1可通过下调酪氨酸酶活性减少酪氨酸酶相关蛋白的表达，最终抑制黑色素的合成，起到美白皮肤作用[36]。Chang等[37]将ADSCs悬液注射到小鼠耳背部皮下后使用波紫外线照射2 d，组织切片中可观察到实验组比对照组皮肤黑色素合成沉着减少、黑素细胞数量更少、酪氨酸酶活性和黑色素含量更低。Jeon等[38]的动物实验中也显示类似的结果。这些研究提示ADSCs具有抗黑色素生成、美白皮肤的作用。 2.2.3 辅助脂肪移植伴随着衰老，面部皮下组织萎缩，皮肤失去一定容积的支撑，出现川字纹、法令纹、木偶纹等较深的皱纹，以及上睑、太阳穴、面颊等处的凹陷，使人看上去衰老憔悴。在ADSCs辅助脂肪移植技术出现前，临床上依靠单纯移植颗粒脂肪进行软组织填充。脂肪组织移植后48 h才会出现血管再生，这种血运建立的不及时造成局部组织缺氧，脂肪细胞坏死、液化吸收，脂肪囊形成和脂肪存活率低等问题[39]。研究发现，ADSCs对缺氧的耐受能力要远高于普通移植脂肪组织[40]。在缺氧环境下ADSCs可聚集于血管周围，分泌释放碱性成纤维细胞生长因子、肝细胞生长因子、血管内皮生长因子、胰岛素样生长因子1等多种血管生成相关因子，促进脂肪组织的血管再生，提高脂肪细胞抗缺氧的能力并抑制其凋亡[41-43]。利用ADSCs这一旁分泌能力，Yoshimura等[44-47]于2006年提出使用自体ADSCs辅助脂肪移植技术，这一技术为脂肪移植提供了一种更为有效可靠的方法。Matsumoto等[48]将自体ADSCs辅助脂肪移植技术应用于小鼠模型，系统分析后证实自体ADSCs辅助脂肪移植技术方式移植的脂肪细胞成活率更高，较单独脂肪移植方式平均上升35%。此外，Charles-de-Sa等[49]将ADSCs混合脂肪组织进行皮下注射抗衰老，治疗后3个月患者脂肪组织存活良好，并且皮肤的超微结构也显示出明显的年轻化趋势。 2.2.4 促进毛发生长毛发生长周期可分为生长期、退行期及休止期，成人正常状态时至少80%的头皮毛囊处于生长期。当因衰老、内分泌失调、精神等原因导致大量毛囊从生长期提前进入休止期后，正常的终毛便会脱落导致脱发。 ADSCs分泌的大量生长因子如胰岛素样生长因子结合蛋白(IGFBP-1、IGFBP-2)、巨噬细胞集落刺激因子、血小板衍生生长因子等可刺激毛囊生长，调节毛发周期，使更多毛囊进入生长期，从而促进毛发的再生[50-51]。Won等[52]在动物实验中观察到，应用皮内注射或皮外涂抹ADSC-CM，都可明显促进毛发再生。2015年Fukuoka等[53]报道了22例脱发患者的临床试验研究，他将ADSC-CM进行头皮内注射，经过6个月的治疗患者头发数量和密度均显著提高。Shin等[54]的临床实验也证实了自体ADSCs条件培养基对于脱发的治疗效果。 2.3 增强ADSCs旁分泌功能的方法 ADSCs的旁分泌作用受到多种因素的影响，直接关系到最终的治疗效果，因此增强其旁分泌功能对于在临床中的应用十分必要。 2.3.1 低氧 ADSCs在低氧环境(1%O2)下血管内皮生长因子分泌量比正常氧环境下可提高约5倍，同时血管内皮生长因子编码mRNA也提高7.4倍，并且经低氧处理后的ADSCs条件培养基能明显促进血管内皮细胞的生长和减少内皮细胞凋亡[22]。Park等[50]发现ADSCs经低氧(2%O2，5%CO2)处理后，血管内皮生长因子、血小板衍生生长因子、肝细胞生长因子、胰岛素样生长因子结合蛋白1、胰岛素样生长因子结合蛋白2、粒-巨噬细胞集落刺激因子等明显增加。Hsiao等[55]的在体实验也证实了这一点。研究人员认为ADSCs旁分泌功能增强的机制可能是低氧诱导NADPH酶活化，导致活性氧的产生增多，随着ERK和Akt信号通路的激活，最终提高生长因子的分泌[56-57]。 2.3.2 培养支架为细胞提供一个更加接近体内生存条件的微环境，可促进ADSCs的旁分泌作用。Collawn等[58]在真皮替代物支架中立体培养ADSCs，发现ADSCs分泌较高的表皮生长因子、成纤维生长因子和转化生长因子β等，对于激光造成的真皮损伤大鼠模型具有更好的促进皮肤损伤修复效果。 2.3.3 基因改造 Shi等[59]将内皮细胞一氧化氮合酶嵌入ADSCs，增加了NO的合成与分泌，用于心肌梗死的治疗具有更好的效果。Shevchenko等[60]将血管内皮生长因子165基因转导入ADSCs后，血管内皮生长因子的表达、合成及分泌增高，从而提高ADSCs促进缺血组织血管再生的能力。 2.3.4 细胞因子及激素 Heo等[61]发现ADSCs经T肿瘤坏死因子α处理后，ADSC-CM促皮肤创伤愈合能力增强，其机制是肿瘤坏死因子α刺激ADSCs分泌的白细胞介素6和白细胞介素8明显增多，进一步加速伤口闭合、血管生成以及创伤部位免疫细胞的增殖和浸润。Hye等[62]观察到PDGF也可增加ADSCs分泌的生长因子。此外，经胰岛素处理的ADSCs能显著促进血管内皮细胞增殖、迁移并抑制其凋亡，可能与胰岛素促进ADSCs分泌更多促细胞增殖、迁移和抗凋亡的细胞因子(如血管内皮生长因子、肝细胞生长因子等)有关[63]。 2.3.5 维生素 Kim等[64]发现ADSCs培养基中添加维生素C后，ERK1/2的磷酸化增强，通过MAPK信号通路增强ADSCs的增殖和分泌能力；同时细胞增殖相关的基因(包括Fos、E2F2、Ier 2、Myb11、Cdc45、JunB、FosB和Cdca5等)表达提高，肝细胞生长因子、胰岛素样生长因子结合蛋白6、血管内皮生长因子、碱性成纤维细胞生长因子、角质细胞生长因子等生长因子的分泌增多。Jung等[65]使用维生素D3处理ADSCs，观察到血管内皮生长因子的分泌明显增多，其机制与维生素C促进ADSCs分泌的作用类似。 2.3.6 紫外线大剂量波紫外线照射会损伤细胞，但是低剂量(10-20 mJ/cm2)的波紫外线反而可显著增强细胞生存/有丝分裂相关信号分子(Akt、β-catenin和ERK1/2)的磷酸化作用，提高ADSCs的生存能力，上调生长因子的表达，其中碱性成纤维细胞生长因子、角质细胞生长因子、肝细胞生长因子和血管内皮生长因子的表达及合成增加最为显著[51]。"

References

[1] Zuk PA,Zhu M,Mizuno H,et al.Multilineage cells from human adipose tissue: implications for cell-based therapies.Tissue Eng.2001;7(2):211-228.

[2] Uzbas F,May ID,Parisi AM,et al.Molecular physiognomies and applications of adipose-derived stem cells.Stem Cell Rev. 2015; 11(2):298-308.

[3] Baptista LS,Silva KR,Borojevic R.Obesity and weight loss could alter the properties of adipose stem cells?World J Stem Cells.2015;7(1):165-173.

[4] Takahashi M,Suzuki E,Oba S,et al.Adipose tissue-derived stem cells inhibit neointimal formation in a paracrine fashion in rat femoral artery.Am J Physiol Heart Circ Physiol.2010; 298(2):H415-H423.

[5] Eto H,Suga H,Inoue K,et al.Adipose injury-associated factors mitigate hypoxia in ischemic tissues through activation of adipose-derived stem/progenitor/stromal cells and induction of angiogenesis.Am J Pathol.2011;178(5): 2322-2332.

[6] Nauta A,Seidel C,Deveza L,et al.Adipose-derived stromal cells overexpressing vascular endothelial growth factor accelerate mouse excisional wound healing.Mol Ther.2013; 21(2):445-455.

[7] Lin YC,Grahovac T,Oh SJ,et al.Evaluation of a multi-layer adipose-derived stem cell sheet in a full-thickness wound healing model.Acta Biomater.2013;9(2):5243-5250.

[8] Mazo M,Planat-Benard V,Abizanda G,et al.Transplantation of adipose derived stromal cells is associated with functional improvement in a rat model of chronic myocardial infarction. Eur J Heart Fail.2008;10(5):454-462.

[9] Gimble JM,Bunnell BA,Guilak F.Human adipose-derived cells: an update on the transition to clinical translation.Regen Med. 2012;7(2):225-235.

[10] Mangi AA,Noiseux N,Kong D,et al.Mesenchymal stem cells modified with Akt prevent remodeling and restore performance of infarcted hearts.Nat Med.2003;9(9): 1195-1201.

[11] Gnecchi M,He H,Liang OD,et al.Paracrine action accounts for marked protection of ischemic heart by Akt-modified mesenchymal stem cells.Nat Med.2005;11(4):367-368.

[12] Fukuda K.Development of regenerative cardiomyocytes from mesenchymal stem cells for cardiovascular tissue engineering. Artif Organs.2001;25(3):187-193.

[13] Gnecchi M,He H,Noiseux N,et al.Evidence supporting paracrine hypothesis for Akt-modified mesenchymal stem cell-mediated cardiac protection and functional improvement. FASEB J.2006;20(6):661-669.

[14] Sadat S,Gehmert S,Song YH,et al.The cardioprotective effect of mesenchymal stem cells is mediated by IGF-I and VEGF.Biochem Biophys Res Commun.2007;363(3):674-679.

[15] Kinnaird T,Stabile E,Burnett MS,et al.Marrow-derived stromal cells express genes encoding a broad spectrum of arteriogenic cytokines and promote in vitro and in vivo arteriogenesis through paracrine mechanisms.Circ Res.2004; 94(5):678-685.

[16] Takahashi M,Li TS,Suzuki R,et al.Cytokines produced by bone marrow cells can contribute to functional improvement of the infarcted heart by protecting cardiomyocytes from ischemic injury.Am J Physiol Heart Circ Physiol. 2006; 291(2):H886-H893.

[17] Ranganath SH,Levy O,Inamdar MS,et al.Harnessing the mesenchymal stem cell secretome for the treatment of cardiovascular disease.Cell Stem Cell.2012;10(3):244-258.

[18] Kim WS,Park BS,Sung JH,et al.Wound healing effect of adipose-derived stem cells: a critical role of secretory factors on human dermal fibroblasts.J Dermatol Sci. 2007; 48(1):15-24.

[19] Park BS,Jang KA,Sung JH,et al.Adipose-derived stem cells and their secretory factors as a promising therapy for skin aging.Dermatol Surg.2008;34(10):1323-1326.

[20] Song SY,Chung HM,Sung JH.The pivotal role of VEGF in adipose-derived-stem-cell-mediated regeneration.Expert Opin Biol Ther. 2010;10(11):1529-1537.

[21] Blaber SP,Webster RA,Hill CJ,et al.Analysis of in vitro secretion profiles from adipose-derived cell populations.J Transl Med.2012;10:172.

[22] Rehman J,Traktuev D,Li J,et al.Secretion of angiogenic and antiapoptotic factors by human adipose stromal cells. Circulation. 2004;109(10):1292-1298.

[23] Salgado AJ,Reis RL,Sousa NJ,et al.Adipose tissue derived stem cells secretome: soluble factors and their roles in regenerative medicine.Curr Stem Cell Res Ther. 2010;5(2):103-110.

[24] Kalra H,Simpson RJ,Ji H,et al.Vesiclepedia: a compendium for extracellular vesicles with continuous community annotation.PLoS Biol.2012;10(12):e1001450.

[25] Gyorgy B,Szabo TG,Pasztoi M,et al.Membrane vesicles, current state-of-the-art: emerging role of extracellular vesicles.Cell Mol Life Sci.2011;68(16):2667-2688.

[26] Lataillade JJ,Clay D,Bourin P,et al.Stromal cell-derived factor 1 regulates primitive hematopoiesis by suppressing apoptosis and by promoting G(0)/G(1) transition in CD34(+) cells: evidence for an autocrine/paracrine mechanism.Blood. 2002; 99(4):1117-1129.

[27] Lee SH,Jin SY,Song JS,et al.Paracrine effects of adipose-derived stem cells on keratinocytes and dermal fibroblasts.Ann Dermatol.2012;24(2):136-143.

[28] Gir P,Oni G,Brown SA,et al.Human adipose stem cells: current clinical applications.Plast Reconstr Surg.2012;129(6):1277-1290.

[29] Farage MA,Miller KW,Elsner P,et al.Characteristics of the Aging Skin.Adv Wound Care(New Rochelle).2013;2(1):5-10.

[30] Ganceviciene R,Liakou AI,Theodoridis A,et al.Skin anti-aging strategies. Dermatoendocrinol.2012;4(3):308-319.

[31] Kim WS,Park BS,Kim HK,et al.Evidence supporting antioxidant action of adipose-derived stem cells: protection of human dermal fibroblasts from oxidative stress.J Dermatol Sci.2008;49(2):133-142.

[32] Kim WS,Park BS,Sung JH.Protective role of adipose-derived stem cells and their soluble factors in photoaging.Arch Dermatol Res.2009;301(5):329-336.

[33] Kim WS,Park BS,Park SH,et al.Antiwrinkle effect of adipose-derived stem cell: activation of dermal fibroblast by secretory factors.J Dermatol Sci. 2009;53(2):96-102.

[34] Kim JH,Jung M,Kim HS,et al. Adipose-derived stem cells as a new therapeutic modality for ageing skin.Exp Dermatol.2011; 20(5):383-387.

[35] 田雅光,刘晓燕,陶凯,等.脂肪来源干细胞辅助下的面部年轻化治疗[J].中国组织工程研究,2012,16(49):257-264.

[36] Kim WS,Park SH,Ahn SJ,et al.Whitening effect of adipose-derived stem cells: a critical role of TGF-beta 1.Biol Pharm Bull.2008;31(4):606-610.

[37] Chang H,Park JH,Min KH,et al.Whitening effects of adipose-derived stem cells: a preliminary in vivo study. Aesthetic Plast Surg.2014;38(1):230-233.

[38] Jeon BJ,Kim DW,Kim MS,et al.Protective effects of adipose-derived stem cells against UVB-induced skin pigmentation.J Plast Surg Hand Surg.2016:1-7.

[39] Saunders MC,Keller JT,Dunsker SB,et al.Survival of autologous fat grafts in humans and in mice.Connect Tissue Res.1981;8(2):85-91.

[40] Mylotte LA,Duffy AM,Murphy M,et al. Metabolic Flexibility Permits Mesenchymal Stem Cell Survival in an Ischemic Environment.Stem Cells.2008;26(5):1325-1336.

[41] Uysal AC,Mizuno H,Tobita M,et al.The effect of adipose-derived stem cells on ischemia-reperfusion injury: immunohistochemical and ultrastructural evaluation.Plast Reconstr Surg.2009;124(3):804-815.

[42] Zhu M,Zhou Z,Chen Y,et al.Supplementation of fat grafts with adipose-derived regenerative cells improves long-term graft retention.Ann Plast Surg. 2010;64(2):222-228.

[43] Thangarajah H,Vial IN,Chang E,et al.IFATS Collection: Adipose Stromal Cells Adopt a Proangiogenic Phenotype Under the Influence of Hypoxia.Stem Cells. 2009;27(1): 266-274.

[44] Yoshimura K,Sato K,Aoi N,et al.Cell-assisted lipotransfer for facial lipoatrophy: efficacy of clinical use of adipose-derived stem cells.Dermatol Surg. 2008;34(9):1178-1185.

[45] Yoshimura K,Suga H,Eto H.Adipose-derived stem/progenitor cells: roles in adipose tissue remodeling and potential use for soft tissue augmentation.Regen Med. 2009;4(2):265-273.

[46] Yoshimura K,Sato K,Aoi N,et al.Cell-assisted lipotransfer for cosmetic breast augmentation: supportive use of adipose-derived stem/stromal cells.Aesthetic Plast Surg. 2008;32(1):48-55,56-57.

[47] Yoshimura K,Asano Y,Aoi N,et al.Progenitor-Enriched Adipose Tissue Transplantation as Rescue for Breast Implant Complications.Breast J.2010;16(2):169-175.

[48] Matsumoto D,Sato K,Gonda K,et al.Cell-assisted lipotransfer: supportive use of human adipose-derived cells for soft tissue augmentation with lipoinjection.Tissue Eng. 2006;12(12): 3375-3382.

[49] Charles-de-Sa L,Gontijo-de-Amorim NF,Maeda TC,et al.Antiaging treatment of the facial skin by fat graft and adipose-derived stem cells.Plast Reconstr Surg. 2015; 135(4):999-1009.

[50] Park BS,Kim WS,Choi JS,et al.Hair growth stimulated by conditioned medium of adipose-derived stem cells is enhanced by hypoxia: evidence of increased growth factor secretion.Biomed Res.2010;31(1):27-34.

[51] Jeong YM,Sung YK,Kim WK,et al.Ultraviolet B preconditioning enhances the hair growth-promoting effects of adipose-derived stem cells via generation of reactive oxygen species.Stem Cells Dev.2013;22(1):158-168.

[52] Won CH,Yoo HG,Kwon OS,et al.Hair growth promoting effects of adipose tissue-derived stem cells.J Dermatol Sci.2010; 57(2):134-137.

[53] Fukuoka H,Suga H.Hair Regeneration Treatment Using Adipose-Derived Stem Cell Conditioned Medium: Follow-up With Trichograms.Eplasty.2015;15:e10.

[54] Shin H,Ryu HH,Kwon O,et al.Clinical use of conditioned media of adipose tissue-derived stem cells in female pattern hair loss: a retrospective case series study.Int J Dermatol. 2015;54(6):730-735.

[55] Hsiao ST,Lokmic Z,Peshavariya H,et al.Hypoxic conditioning enhances the angiogenic paracrine activity of human adipose-derived stem cells.Stem Cells Dev.2013;22(10): 1614-1623.

[56] Kim JH,Park SH,Park SG,et al.The pivotal role of reactive oxygen species generation in the hypoxia-induced stimulation of adipose-derived stem cells.Stem Cells Dev. 2011;20(10): 1753-1761.

[57] Kim JH,Song SY,Park SG,et al.Primary involvement of NADPH oxidase 4 in hypoxia-induced generation of reactive oxygen species in adipose-derived stem cells.Stem Cells Dev. 2012;21(12):2212-2221.

[58] Collawn SS,Banerjee NS,de la Torre J,et al.Adipose-derived stromal cells accelerate wound healing in an organotypic raft culture model.Ann Plast Surg.2012;68(5):501-504.

[59] Shi CZ,Zhang XP,Lv ZW,et al.Adipose tissue-derived stem cells embedded with eNOS restore cardiac function in acute myocardial infarction model.Int J Cardiol. 2012;154(1):2-8.

[60] Shevchenko EK,Makarevich PI,Tsokolaeva ZI,et al.Transplantation of modified human adipose derived stromal cells expressing VEGF165 results in more efficient angiogenic response in ischemic skeletal muscle.J Transl Med.2013;11:138.

[61] Heo SC,Jeon ES,Lee I H,et al.Tumor necrosis factor-alpha-activated human adipose tissue-derived mesenchymal stem cells accelerate cutaneous wound healing through paracrine mechanisms.J Invest Dermatol.2011; 131(7): 1559-1567.

[62] Hye KJ,Gyu PS,Kim WK,et al.Functional regulation of adipose-derived stem cells by PDGF-D.Stem Cells.2015; 33(2):542-556.

[63] 折涛,胡大海,张彦刚,等.胰岛素干预后脂肪干细胞旁分泌对人血管内皮细胞的作用[J].中华烧伤杂志,2011,27(1):32-36.

[64] Kim JH,Kim WK,Sung YK,et al.The molecular mechanism underlying the proliferating and preconditioning effect of vitamin C on adipose-derived stem cells.Stem Cells Dev. 2014;23(12):1364-1376.

[65] Jung MK,Ha S,Huh SY,et al.Hair-growth stimulation by conditioned medium from vitamin D3-activated preadipocytes in C57BL/6 mice.Life Sci.2015;128:39-46.

[66] Baer PC,Geiger H.Adipose-derived mesenchymal stromal/stem cells: tissue localization, characterization, and heterogeneity.Stem Cells Int.2012;2012:812693.