Targeted delivery of fat extract by platelet membrane-cloaked nanocarriers for the treatment of ischemic stroke.

BACKGROUND: Our previous studies suggest that human fat extract (FE) contains a variety of angiogenic factors and may provide an alternative treatment option for stroke. However, the therapeutic effect is largely limited due to its short half-life, and inaccurate targeting. RESULTS: Herein, we leverage the targeting abilities of platelets (PLTs) to the lesion area of stroke and Arg-Gly-Asp (RGD) peptides to the angiogenic blood vessels to develop a biomimetic nanocarrier that capable of delivering FE precisely to treat stroke. The biomimetic nanocarriers are comprised of FE-encapsulated PLGA (poly(lactic-co-glycolic acid)) core enclosed by RGD peptides decorated plasma membrane of PLTs, namely RGD-PLT@PLGA-FE. We found that RGD-PLT@PLGA-FE not only targeted damaged and inflamed blood vessels but also achieved rapid accumulation in the lesion area of ischemic brain. In addition, RGD-PLT@PLGA-FE kept a sustained release behavior of FE at the lesion site, effectively increased its half-life and promoted angiogenesis and neurogenesis with delivering neurotrophic factors including BDNF, GDNF and bFGF to the brain, that ultimately resulted in blood flow increase and neurobehavioral recovery. CONCLUSIONS: In conclusion, our study provides a new strategy to design a biomimetic system for FE delivery and it is a promising modality for stroke therapy.

Cell-Free Fat Extract Prevents Vaginal Atrophy in an Ovariectomized Model by Promoting Proliferation of Vaginal Keratinocytes and Neovascularization.

BACKGROUND: Most perimenopausal and postmenopausal women experience estrogen deficiency-induced vaginal atrophy. However, estrogen replacement therapy has contraindications and side effects, which makes it unsuitable for most women. Cell-free fat extract (CEFFE) has pro-proliferative and proangiogenic tissue regeneration activities. OBJECTIVES: The purpose of this study was to evaluate the effect of topical application of CEFFE in the vagina and the effect of CEFFE on vaginal keratinocytes. METHODS: Ovariectomized mice were treated with CEFFE via vaginal topical application for 2 weeks. The vaginal mucosal cell layer number, mucosal thickness, and vaginal collagen volume were determined by histologic analyses. Vaginal mucosa proliferation and lamina propria angiogenesis were evaluated with anti-proliferating cell nuclear antigen and anti-CD31 staining, respectively. For in vitro analysis, VK2/E6E7 cells were administered, increasing the CEFFE concentration. Cell proliferation and cell-cycle distribution were analyzed by Cell Counting Kit 8 assay and flow cytometry, respectively. Mucosal migration was evaluated with a wound-healing assay. The expression of Ki-67 and estrogen-related proteins was detected by western blotting. RESULTS: CEFFE-treated mice showed increased mucosal thickness and number of vaginal mucosal cell layers and reduced vaginal atrophy compared to ovariectomized mice. The number of proliferating cell nuclear antigen-positive cells and CD31-positive capillaries also increased. In addition, CEFFE promoted the proliferation and migration of VK2/E6E7 cells, upregulated the expression of Ki-67, and inhibited the expression of estrogen-related proteins and the PI3K/AKT pathway. CONCLUSIONS: CEFFE prevents estrogen deficiency-induced vaginal atrophy by promoting vaginal mucosal proliferation and increasing neovascularization, but not through the estrogen/estrogen receptor pathway, in an ovariectomized mouse model.

Human umbilical cord mesenchymal stem cell-derived and dermal fibroblast-derived extracellular vesicles protect dermal fibroblasts from ultraviolet radiation-induced photoaging in vitro.

Ultraviolet B (UVB) radiation is a major cause of aging in dermal fibroblasts. Human umbilical cord mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) show antioxidant activity. In this study, the anti-aging effects of MSC-EVs on dermal fibroblast photoaging induced by UVB radiation were evaluated, and the effects of extracellular vesicles derived from dermal fibroblasts (Fb-EVs) were compared. Human umbilical cord mesenchymal stem cells and human dermal fibroblasts were cultured, and MSC-EVs and Fb-EVs were isolated and characterized. Human dermal fibroblasts were cultured in the absence or presence of different concentrations of EVs 24 hours prior to UVB radiation exposure. Cell proliferation and cell cycle were evaluated, and senescent cells and intracellular ROS were detected. The expressions of matrix metalloproteinase-1 (MMP-1), extracellular matrix protein collagen type 1 (Col-1), and antioxidant proteins such as glutathione peroxidase 1 (GPX-1), superoxide dismutase (SOD), and catalase were also analyzed. Pretreatment with MSC-EVs or Fb-EVs significantly inhibited the production of ROS induced by UVB radiation, increased dermal fibroblast proliferation, protected cells against UVB-induced cell death and cell cycle arrest, and remarkably decreased the percentage of aged cells. Pretreatment with MSC-EVs or Fb-EVs promoted the expressions of GPX-1 and Col-1 and decreased the expression of MMP-1. Both MSC-EVs and Fb-EVs protected dermal fibroblasts from UVB-induced photoaging, likely through their antioxidant activity.

Cell-Free Fat Extract Increases Dermal Thickness by Enhancing Angiogenesis and Extracellular Matrix Production in Nude Mice.

BACKGROUND: Although adipose-derived stem cells (ADSCs) and nanofat exert antiaging effects on skin, they contain cellular components that have certain limitations in clinical practice. Cell-free fat extract (Ceffe) is a fraction purified from nanofat through removal of cellular components and lipid remnants that contains various growth factors. OBJECTIVES: The purpose of this study was to evaluate the effects of Ceffe on cultured human dermal fibroblasts in vitro and on the dermis of nude mice in vivo. METHODS: In the in vitro study, human dermal fibroblasts were cultured with Ceffe for 72 hours, followed by flow cytometry measurement of cell proliferation and cell cycle. In the in vivo study, different concentrations of Ceffe were injected into the dorsal skin of nude mice for 4 weeks. The thickness of the dermis; proliferation of cells; density of the capillary; and expressions of type I and III collagen (Col-1 and Col-3), matrix metalloproteinase-1, matrix metalloproteinase-3, tissue inhibitor of metalloproteinase-1, and tissue inhibitor of metalloproteinase-3 were measured through histologic and Western blot analyses. RESULTS: Ceffe significantly increased cell proliferation in cultured dermal fibroblasts. In the mouse skin, Ceffe significantly increased the thickness of the dermis, number of proliferating cells, density of the capillary, and expressions of Col-1 and Col-3. CONCLUSIONS: Ceffe increased the dermal thickness of nude mice, possibly by enhancing angiogenesis and extracellular matrix production, and can therefore be used for skin rejuvenation.

Fat Extract Improves Random Pattern Skin Flap Survival in a Rat Model.

BACKGROUND: Adipose tissue and its derivatives, including adipose-derived stem cells, stromal vascular fraction (SVF), and SVF-gel, have been utilized in the treatment of many ischemic disorders. However, the utilization of these products is limited in clinical applications by concerns related to the presence of cells in these derivatives. OBJECTIVES: This study aimed to isolate a cell-free fat extract (FE) from fat tissue and to evaluate its proangiogenic ability in vitro as well as its protective effects on skin flap survival in vivo. METHODS: FE was isolated from human fat via a mechanical approach. The concentrations of several growth factors in the FE were determined by enzyme-linked immunosorbent assay. The proangiogenic ability of FE was evaluated utilizing assays of the proliferation, migration, and tube formation in human umbilical vein endothelial cells in vitro. The protective effects of FE on the survival of random pattern skin flaps were investigated by subcutaneous injection into rats. RESULTS: Enzyme-linked immunosorbent assay results revealed that FE contained proangiogenic growth factors that promoted proliferation, migration, and tube formation in human umbilical vein endothelial cells in vitro. In addition, FE reduced skin flap necrosis and increased survival, as demonstrated by macroscopic measurements and blood flow analysis. Histological analysis revealed that FE treatment increased the capillary density. CONCLUSIONS: FE is a cell-free, easy-to-prepare, and growth-factor-enriched liquid derived from human adipose tissue that possesses proangiogenic activity and improves skin flap survival by accelerating blood vessel formation. FE may be potentially used for treating ischemic disorders.

Cell-Free Fat Extract Prevents Tail Suspension-Induced Bone Loss by Inhibiting Osteocyte Apoptosis.

Introduction: As the space field has developed and our population ages, people engaged in space travel and those on prolonged bed rest are at increasing risk for bone loss and fractures. Disuse osteoporosis occurs frequently in these instances, for which the currently available anti-osteoporosis agents are far from satisfactory and have undesirable side effects. CEFFE is a cell-free fraction isolated from nanofat that is enriched with a variety of growth factors, and we aim to investigate its potential therapeutic effects on disuse osteoporosis. Methods: A tail suspension-induced osteoporosis model was applied in this study. Three weeks after tail suspension, CEFFE was intraperitoneally injected, and PBS was used as a control. The trabecular and cortical bone microstructures of the tibia in each group were assessed by µCT after 4 weeks of administration. Osteocyte lacunar-canalicularity was observed by HE and silver staining. In vitro, MLO-Y4 cell apoptosis was induced by reactive oxygen species (ROSUP). TUNEL staining and flow cytometry were used to detect apoptosis. CCK-8 was used to detect cell proliferation, and Western blotting was used to detect MAPK signaling pathway changes. Results: CEFFE increased the bone volume (BV/TV) and trabecular number (Tb.N) of the trabecular bone and increased the thickness of the cortical bone. HE and silver staining results showed that CEFFE reduced the number of empty lacunae and improved the lacuna-canalicular structure. CEFFE promoted osteocyte proliferative capacity in a dose-dependent manner. CEFFE protected MLO-Y4 from apoptosis by activating the serine/threonine-selective protein kinase (ERK) signaling pathways. Conclusion: CEFFE attenuated immobilization-induced bone loss by decreasing osteocyte apoptosis. CEFFE increased the survival of osteocytes and inhibited osteocyte apoptosis by activating the ERK signaling pathway in vitro.

Multifunctional Magnesium Organic Framework-Based Microneedle Patch for Accelerating Diabetic Wound Healing.

Diabetic wound healing is one of the major challenges in the biomedical fields. The conventional single drug treatments have unsatisfactory efficacy, and the drug delivery effectiveness is restricted by the penetration depth. Herein, we develop a magnesium organic framework-based microneedle patch (denoted as MN-MOF-GO-Ag) that can realize transdermal delivery and combination therapy for diabetic wound healing. Multifunctional magnesium organic frameworks (Mg-MOFs) are mixed with poly(γ-glutamic acid) (γ-PGA) hydrogel and loaded into the tips of MN-MOF-GO-Ag, which slowly releases Mg2+ and gallic acid in the deep layer of the dermis. The released Mg2+ induces cell migration and endothelial tubulogenesis, while gallic acid, a reactive oxygen species-scavenger, promotes antioxidation. Besides, the backing layer of MN-MOF-GO-Ag is made of γ-PGA hydrogel and graphene oxide-silver nanocomposites (GO-Ag) which further enables excellent antibacterial effects for accelerating wound healing. The therapeutic effects of MN-MOF-GO-Ag on wound healing are demonstrated with the full-thickness cutaneous wounds of a diabetic mouse model. The significant improvement of wound healing is achieved for mice treated with MN-MOF-GO-Ag.

Cell-free fat extract accelerates diabetic wound healing in db/db mice.

Cell-free fat extract (CEFFE), the liquid fraction derived from fat tissues, is enriched with a variety of growth factors and possesses pro-angiogenic, anti-apoptotic, and anti-oxidative properties. The aim of this study was to determine if CEFFE could accelerate chronic wound healing in mice with diabetes and investigate its underlying mechanisms. A model of circular full-thickness wound (6 mm diameter) was produced in the central dorsal region of spontaneous type 2 diabetes mellitus db/db mice. The mice were divided to three groups depending on dosage of CEFFE administered for the study; high dose CEFFE group (CEFFEhigh; administered 2.5 ml/kg/day via subcutaneous injection for six days), low dose CEFFE group (CEFFElow; administered 2.5 ml/kg/day via subcutaneous injection for three days), and a control group receiving phosphate buffer solution. Wound closure was evaluated on day 3, 7, 10, and 14 post-operation. Histological analyses, including hematoxylin-eosin staining and Masson's trichrome staining and immunohistological staining of anti-CD31 and anti-CD68, were also performed. Moreover, the effects of CEFFE on proliferation, migration, and tube formation of human immortal keratinocyte cells (HaCaT) and human vascular endothelial cells (HUVEC) were tested in vitro. The results showed that the local injection of CEFFE significantly accelerated wound healing in mice with diabetes. CEFFE improved re-epithelization and collagen secretion, promoted angiogenesis, and inhibited inflammatory macrophage infiltration in vivo. CEFFE also promoted HaCaT proliferation and migration and enhanced tubular formation in cultured HUVEC. It was concluded that CEFFE accelerates wound healing through pro-angiogenic and anti-inflammatory activities.

γ-PGA hydrogel loaded with cell-free fat extract promotes the healing of diabetic wounds.

Diabetic wounds are one complication of persistent hyperglycemia and lead to neuropathy and vascular lesions in patients. The promotion of angiogenesis plays an important role in wound healing. Cell-free fat extract (Ceffe) is a cell-free fraction isolated from adipose that is enriched with a range of growth factors, the combination of which can synergistically induce angiogenesis. In this study, we prepared a wound dressing by loading Ceffe with the γ-PGA hydrogel (Ceffe-γ-PGA) to promote the healing of wounds in diabetic mice. The viscosity of Ceffe-γ-PGA was 9.2 pa s, and the water retention rate after 6 hours reached 50%. The slow-release effect of the Ceffe-γ-PGA hydrogel was investigated in vitro in PBS, and the cumulative release rate was 97% after 6 days. Water retention and viscosity analyses revealed that Ceffe-γ-PGA provided a moist environment for the wound surface. The therapeutic effect of the Ceffe-γ-PGA hydrogel on wound healing was studied in vivo in type-II diabetic male db/db mice. After 17 days of wound treatment, the wound area ratio of the Ceffe-γ-PGA group was reduced to 2% of the original, and the capillary density of the Ceffe-γ-PGA group reached 33 mm-2 and was 19 mm-2 higher than that of the untreated group. The cell proliferation rate in the Ceffe-γ-PGA group was 37% higher than that in the untreated group. These results support the use of this system as a promising therapeutic strategy for wound healing in patients with diabetes.

Cell-free fat extract promotes tissue regeneration in a tissue expansion model.

BACKGROUND: Tissue expansion techniques play an important role in plastic surgery. How to improve the quality of the expanded skin and shorten the expansion period are still worth investigating. Our previous studies found that a cell-free fat extract (CEFFE) possessed pro-angiogenic and pro-proliferative activities. However, the role of CEFFE on tissue expansion has remained unclear. The purpose of this study was to evaluate the effect of CEFFE on tissue expansion. METHODS: A rat tissue expansion model was used. Animals were treated with CEFFE by subcutaneous injection. After 4 weeks of tissue expansion, the skin necrosis and retraction rates were evaluated, the thicknesses of the epidermis and dermis were determined by histological analyses, blood vessel density was measured by anti-CD31 staining, cell proliferation was assessed by proliferating cell nuclear antigen staining, and the expression of specific proteins was evaluated by western blot analyses. In addition, the effects of CEFFE on the proliferation and cell cycle of cultured HaCaT cells were evaluated in vitro. RESULTS: CEFFE treatment significantly decreased the necrosis rate and retraction of the expanded skin. The thickness of the epidermal and dermal layers was higher in CEFFE-treated compared to untreated skin. The density of blood vessels and cell proliferation in the epidermis of the expanded skin was improved by CEFFE treatment. In addition, CEFFE treatment significantly increased the expression of the vascular endothelial growth factor receptor, epidermal growth factor receptor, collagen type 1, and collagen type 3. CEFFE also increased the proliferation of HaCaT cells in culture. CONCLUSIONS: CEFFE improves the quality of the expanded skin by promoting angiogenesis and cell proliferation. It could be potentially used clinically for augmenting tissue expansion.

Dual-modal non-invasive imaging in vitro and in vivo monitoring degradation of PLGA scaffold based gold nanoclusters.

Biodegradable scaffolds play an important role in tissue engineering, and appropriate degradation and resorption rates of these scaffolds are necessary to accommodate tissue growth. Synthetic polymers are frequently used because of their ease of production, good biocompatibility and controllable degradation rates. However, monitoring the degradation of these polymers in vivo by a noninvasive approach remains limited. In this study, we designed a composite scaffold by labeling poly(lactic-co-glycolic acid) (PLGA) with gold nanoclusters (Au NCs), which were used for tracking in vivo degradation through dual-modal fluorescence/computed tomography (CT) imaging. The diameter of the Au NCs was approximately 2.5 nm, and the emission peak was at a wavelength of 700 nm. After labeling PLGA with the Au NCs, the fluorescence intensity of the Au NC/PLGA composite scaffold reached 9.0 × 109 (p/s/cm2/sr)/(µW/cm2), and the CT density of the scaffold increased to 200 HU. After the composite scaffold was implanted subcutaneously into nude mice, a continuous decrease in the fluorescence signal and CT value was observed. The mean fluorescence intensity was 8.3 × 109, 3.17 × 109, 2.26 × 109, 2.11 × 109, and 1.82 × 109 (p/s/cm2/sr)/(µW/cm2) from the first week to the fifth week, respectively. The mean CT value changed from 222.6 to 185.9, 149.1, 112.5, and 55.2 (Hounsfield unit, HU) at the different timepoints. Compared with the change in the fluorescence intensity, the change in the CT value was similar to the change in the weight, and the Pearson correlation coefficient between the change in the CT value and weight was 0.8626. Furthermore, the structure and morphology of the scaffolds at different timepoints were analyzed by three-dimensional (3-D) reconstruction. This novel method of noninvasive dynamic monitoring of biodegradable polymers in vivo provides insight into choosing suitable biomaterials for tissue engineering and regenerative medicine.

Protective Effect of Fat Extract on UVB-Induced Photoaging In Vitro and In Vivo.

BACKGROUND: Nanofat can protect against ultraviolet B- (UVB-) induced damage in nude mice. Fat extract (FE) is a cell-free fraction isolated from nanofat that is enriched with a variety of growth factors. OBJECTIVE: To determine whether FE can protect against UVB-induced photoaging in cultured dermal fibroblasts and in nude mice. METHOD: For the in vitro study, human dermal skin fibroblasts were pretreated with FE 24 h prior to UVB irradiation. Generation of reactive oxygen species (ROS) was analyzed immediately following irradiation, while cell cycle analysis was performed 24 h after UVB irradiation. Senescence-associated ß-galactosidase (SA-ß-gal) expression, cell proliferation, and expression of glutathione peroxidase 1 (GPX-1), catalase, superoxide dismutase-1 (SOD-1), SOD-2, and collagen type 1 (COL-1) were investigated 72 h after UVB irradiation. For the in vivo study, the dorsal skin of nude mice was irradiated with UVB and mice were then treated with FE for 8 weeks. The thickness of the dermis, capillary density, and apoptotic cells in skin tissue sections were investigated after treatment. The expression of GPX-1, catalase, SOD-2, SOD-1, and COL-1 in the tissue was also measured. RESULT: FE significantly increased cell proliferation and protected cells against UVB-induced cell death and cell cycle arrest. FE reduced ROS and the number of aged cells induced by UVB irradiation. FE promoted the expression of COL-1 and GPX-1 in cultured dermal fibroblasts. FE treatment of UVB-irradiated skin increased dermal thickness and capillary density, decreased the number of apoptotic cells, and promoted the expression of COL-1 and GPX-1. CONCLUSION: FE protects human dermal fibroblasts and the skin of nude mice from UVB-induced photoaging through its antioxidant, antiapoptotic, and proangiogenic activities.

Fat extract improves fat graft survival via proangiogenic, anti-apoptotic and pro-proliferative activities.

BACKGROUND: Our previous study proved that nanofat could enhance fat graft survival by promoting neovascularization. Fat extract (FE), a cell-free component derived from nanofat, also possesses proangiogenic activity. OBJECTIVES: The aim of this study was to investigate whether FE could improve fat graft survival and whether FE and nanofat could work synergistically to promote fat graft survival. The underlying mechanism was also investigated. METHODS: In the first animal study, human macrofat from lipoaspirate was co-transplanted into nude mice with FE or nanofat. The grafts were evaluated at 2, 4 and 12 weeks post-transplantation. In the second animal study, nude mice were transplanted with a mixture of macrofat and nanofat, followed by intra-graft injection of FE at days 1, 7, 14, 21 and 28 post-transplantation. The grafts were evaluated at 12 weeks post-transplantation. To detect the mechanism by which FE impacts graft survival, the proangiogenic, anti-apoptotic and pro-proliferative activities of FE were analysed in grafts in vivo and in cultured human vascular endothelial cells (HUVECs), adipose-derived stem cells (ADSCs) and fat tissue in vitro. RESULTS: In the first animal study, the weights of the fat grafts in the nanofat- and FE-treated groups were significantly higher than those of the fat grafts in the control group. In addition, higher fat integrity, more viable adipocytes, more CD31-positive blood vessels, fewer apoptotic cells and more Ki67-positive proliferating cells were observed in the nanofat- and FE-treated groups. In the second animal study, the weights of the fat grafts in the nanofat+FE group were significantly higher than those of the fat grafts in the control group. In vitro, FE showed proangiogenic effects on HUVECs, anti-apoptotic effects on fat tissue cultured under hypoxic conditions and an ability to promote ADSC proliferation and maintain their multiple differentiation capacity. CONCLUSIONS: FE could improve fat graft survival via proangiogenic, anti-apoptotic and pro-proliferative effects on ADSCs. FE plus nanofat-assisted fat grafting is a new strategy that could potentially be used in clinical applications.

Cell-mediated delivery of VEGF modified mRNA enhances blood vessel regeneration and ameliorates murine critical limb ischemia.

Synthetic chemically modified mRNAs (modRNA) encoding vascular endothelial growth factor (VEGF) represents an alternative to gene therapy for the treatment of ischemic cardiovascular injuries. However, novel delivery approaches of modRNA are needed to improve therapeutic efficacy in the diseased setting. We hypothesized that cell-mediated modRNA delivery may enhance the in vivo expression kinetics of VEGF protein thus promoting more potent angiogenic effects. Here, we employed skin fibroblasts as a "proof of concept" to probe the therapeutic potential of a cell-mediated mRNA delivery system in a murine model of critical limb ischemia (CLI). We show that fibroblasts pre-treated with VEGF modRNA have the potential to fully salvage ischemic limbs. Using detailed molecular analysis we reveal that a fibroblast-VEGF modRNA combinatorial treatment significantly reduced tissue necrosis and dramatically improved vascular densities in CLI-injured limbs when compared to control and vehicle groups. Furthermore, fibroblast-delivered VEGF modRNA treatment increased the presence of Pax7+ satellite cells, indicating a possible correlation between VEGF and satellite cell activity. Our study is the first to demonstrate that a cell-mediated modRNA therapy could be an alternative advanced strategy for cardiovascular diseases.

Fat extract promotes angiogenesis in a murine model of limb ischemia: a novel cell-free therapeutic strategy.

BACKGROUND: The proangiogenic capacity of adipose tissue and its derivatives has been demonstrated in a variety of studies. The paracrine mechanism of the cellular component is considered to play a critical role in the regenerative properties of these tissues. However, cell-based therapy for clinical application has been hindered by limitations such as safety, immunogenicity issues, and difficulties in cell preservation, transportation, and phenotype control. In the current study, we aimed to produce a cell-free extract directly from human fat tissue and evaluate its potential therapeutic efficacy. METHODS: We developed a novel physical approach to produce a cell-free aqueous extract from human fat tissue (fat extract (FE)). The therapeutic potential of FE was investigated in the ischemic hindlimb model of nude mice. After establishment of hindlimb ischemia with ligation of the left femoral artery and intramuscular injection of FE, blood perfusion was monitored at days 0, 7, 14, 21, and 28. Tissue necrosis and capillary density were evaluated. Enzyme-linked immunosorbent assay was used to analyze the growth factors contained in FE. Moreover, the proliferation, migration, and tube formation ability were tested on human umbilical vein endothelial cells (HUVECs) in vitro when treated with FE. The proangiogenic ability of FE was further assessed in an in-vivo Matrigel plug assay. RESULTS: FE was prepared and characterized. The intramuscular injection of FE into the ischemic hindlimb of mice attenuated severe limb loss and increased blood flow and capillary density of the ischemic tissue. Enzyme-linked immunosorbent assay showed that FE contained high levels of various growth factors. When added as a cell culture supplement, FE promoted HUVEC proliferation, migration, and tube formation ability in a dose-dependent manner. The subcutaneous injection of Matrigel infused with FE enhanced vascular formation. CONCLUSIONS: We developed a novel cell-free therapeutic agent, FE, produced from human adipose tissue. FE was able to attenuate ischemic injury and stimulate angiogenesis in ischemic tissues. This study indicates that FE may represent a novel cell-free therapeutic agent in the treatment of ischemic disorders.

Biocompatible and Stable GO-Coated Fe3O4 Nanocomposite: A Robust Drug Delivery Carrier for Simultaneous Tumor MR Imaging and Targeted Therapy.

Combined targeted drug delivery and sustained drug release, through the application of nanomedicine, show great potential in cancer therapy and diagnostics. Systems based on folic acid conjugated with graphene oxide-based magnetic nanoparticles (NPs) show distinct advantages for such chemotherapeutic applications. Herein, we prepared FA-Fe3O4@nGO-DOX magnetic nanoparticles (MNPs) with a uniform size distribution based on nanoscale graphene oxide (nGO) encapsulated Fe3O4, which was conjugated with folic acid (FA) and loaded with doxorubicin (DOX). The prepared MNPs were characterized by various biophysical methods and featured a uniform size distribution. The uniform size of the nGO resulted in a relative narrow size distribution of the Fe3O4@nGO MNPs, which contributed to the stability of the nanocarrier system. Cell viability and in vitro biocompatibility studies of the FA-Fe3O4@nGO-DOX NPs revealed their selective uptake by MGC-803 cells. The relative viability was maintained at ∼90% after 48 h of incubation, and the hemolysis ratio confirmed the low toxicity of our modified NPs. The pH-controlled drug release and selective uptake of FA-Fe3O4@nGO NPs by MGC-803 cells via the FA receptor ensured selective killing of tumor cells. Furthermore, the nanoparticles for magnetic resonance imaging were analyzed in vitro and their signal intensity decreased as the NP concentration was increased. The nanocomposite was highly effective for in vivo imaging. Additionally, our in vivo antitumor activity and histological analysis confirmed the selective anticancer activity of the FA-Fe3O4@nGO-DOX NPs. Notably, our NPs were highly active and mice treated with FA-Fe3O4@nGO-DOX showed lower weight loss compared with mice treated with Fe3O4@nGO-DOX. More necrotic tissue was observed in the tumors of the FA-Fe3O4@nGO-DOX group compared with those observed in the control, Fe3O4@nGO-DOX, and DOX groups. Thus, FA-Fe3O4@nGO-DOX is an effective and stable candidate for targeted drug delivery.

Protective effect of crocin on ultraviolet B­induced dermal fibroblast photoaging.

Ultraviolet B (UVB) radiation induces the production of reactive oxygen species (ROS), resulting in the aging of dermal fibroblasts. Crocin, a bioactive constituent of Crocus sativus, possesses anti­oxidation effects. The purpose of the present study was to evaluate the protective effect of crocin on UVB­induced dermal fibroblast photoaging. Human dermal fibroblasts were isolated and cultured with different concentrations of crocin prior to and following exposure to UVB irradiation. The senescent phenotypes of cells were evaluated, including cell proliferation, cell cycle, senescence­associated ß­galactosidase (SA­ß­gal) expression, intracellular ROS, expression of antioxidant protein glutathione peroxidase 1 (GPX­1) and extracellular matrix protein collagen type 1 (Col­1). Crocin rescued the cell proliferation inhibited by UVB irradiation, prevented cell cycle arrest and markedly decreased the number of SA­ß­gal­positive cells. In addition, crocin reduced UVB­induced ROS by increasing GPX­1 expression and other direct neutralization effects. Furthermore, crocin promoted the expression of the extracellular matrix protein Col­1. Crocin could effectively prevent UVB­induced cell damage via the reduction of intracellular ROS; thus, it could potentially be used in the prevention of skin photoaging.