Seongho Han

Cryopreserved human adipogenic-differentiated pre-adipocytes: a potential new source for adipose tissue regeneration

BACKGROUND Previously, we have shown that in vitro adipogenic differentiation of pre-adipocytes before implantation can enhance in vivo adipose tissue formation. For large-scale adipose tissue engineering or repeat procedures, cryopreservation of fat grafts has been commonly used in recent years. However, the feasibility of cryopreservation of adipogenic differentiated pre-adipocytes has not been investigated. METHODS To examine the impact of cryopreservation on the adipogenic functions of adipogenic-differentiated pre-adipocytes, freeze-thawed adipocytes were compared with fresh differentiated adipocytes in vitro and in vivo. Adipogenic function was assessed by Oil red O staining, ELISA analysis of leptin secretion and RT-PCR of adipogenic-related genes. After transplantation, adipose tissue formation was assessed by histomorphologic and volumetric analysis. RESULTS Freeze-thawed adipocytes constantly showed typical adipogenic functions in terms of lipid content, leptin secretion and adipogenic gene expression, as well as good viability. Importantly, implants derived from freeze-thawed adipocytes were successfully developed to adipose tissue and newly formed adipose tissues were similar to those developed from fresh differentiated adipocytes, based on histomorphologic and volumetric analysis. In addition, CD34-positive endothelial cells were detected in implants. These results demonstrate that the specific characters of adipogenic-differentiated pre-adipocytes are successfully conserved after cryopreservation without any significant alteration. DISCUSSION Cryopreservation of adipogenic-differentiated pre-adipocytes is a feasible method and extends their clinical use in adipose tissue-engineering applications and transplantation.

Eriodictyol attenuates cisplatin-induced kidney injury by inhibiting oxidative stress and inflammation

Eriodictyol, a flavonoid present in citrus fruits, has been reported to have antioxidant and anti-inflammatory effects. In this study, the protective effects of eriodictyol on cisplatin (CP)-induced kidney injury were detected. CP-induced kidney injury model was established by administration of CP (20mg/kg). The results showed that treatment of eriodictyol inhibited the production of blood urea nitrogen (BUN), creatinine, MDA, TBARS, reactive oxygen species (ROS), as well as the production of TNF-α, and IL-1β in kidney tissues induced by CP. Eriodictyol also up-regulated the activities of SOD, CAT, and GSH-PX decreased by CP. Furthermore, eriodictyol was found to up-regulate the expression of Nrf2/HO-1 and inhibited CP-induced NF-κB activation in kidney tissues. In conclusion, eriodictyol protected against CP-induced kidney injury through activating Nrf2 and inhibiting NF-κB activation.

Stromal vascular fraction shows robust wound healing through high chemotactic and epithelialization property

BACKGROUND Although human stromal vascular fraction (SVF) has been regarded as an attractive stem cell source, its therapeutic mechanism in wound healing has not been fully elucidated. AIMS In this study, we investigated the molecular characteristics and therapeutic property of SVF for wound healing. METHODS Microarray data showed that SVF cells are enriched with a higher level of wound healing or epithelium development-related genes and micro RNA. RESULTS Quantitative polymerase chain reaction (PCR) and reverse transcriptase PCR results revealed that the epithelialization growth factor, epidermal growth factor (EGF), chemokines, stromal cell-derived factor (SDF-1 or CXCL12), neutrophil-activating protein-2 (NAP-2 or CXCL7), chemokine receptors (CXCR1, CCR2 and CCR3) and wound healing genes were up-regulated in SVF compared with those in adipose-derived mesenchymal stem cells (ASCs). An in vitro scratch wound closure experiment demonstrated that co-culture with SVF substantially accelerated the wound closure of fibroblasts. Wounds in nude mice were created by skin excisions followed by injections of SVF with Pluronic hydrogel. SVF implantation highly accelerated wound closure and increased cellularity and re-epithelialization. In addition, the transplanted SVF exhibited high engraftment rates in the wound area, suggesting direct benefits for cutaneous closure. CONCLUSIONS Taken together, these data suggest that SVF possesses high therapeutic capability for wound healing via the secretion of epithelialization and chemotactic growth factors and enhanced engraftment properties.

Amniotic epithelial cells promote wound healing in mice through high epithelialization and engraftment.

Although human amniotic epithelial cells (AMEs) are an attractive source of stem cells, their therapeutic potential in wound healing has not been fully investigated. We evaluated the therapeutic potential of AMEs for wound healing. Real‐time PCR showed that the epithelialization growth factors epidermal growth factor (EGF), platelet‐derived growth factor (PDGF)‐B and chemotactic factors interleukin‐8 (IL‐8 or CXCL8) and neutrophil‐activating protein‐2 (NAP‐2 or CXCL7) were upregulated in AMEs compared with adipose‐derived mesenchymal stem cells (ADMs). In vitro scratch wound assays revealed that AME‐derived conditioned medium substantially accelerated wound closure. Wounds in NOD/SCID mice were created by skin excision, followed by AME transplantation. AMEs implantation significantly accelerated wound healing and increased cellularity and re‐epithelialization. Transplanted AMEs exhibited high engraftment rates and expressed keratinocyte‐specific proteins and cytokeratin in the wound area, suggesting direct benefits for cutaneous closure. Taken together, these data indicate that AMEs possess therapeutic capability for wound healing through the secretion of epithelialization growth factors and enhanced engraftment properties. Copyright

Ramipril inhibits high glucose-stimulated up-regulation of adhesion molecules via the ERK1/2 MAPK signaling pathway in human umbilical vein endothelial cells.

Abstract Ramipril has recently been shown to have anti-atherogenic properties. However, the specific mechanisms underlying these effects remain unclear. The purpose of this study was to determine the effects of ramipril on induction of adhesion molecules in human umbilical vein endothelial cells (HUVECs) using high-glucose (HG) conditions and to investigate possible underlying molecular mechanisms. The effects of ramipril on expression of intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1 production, and ERK phosphorylation were examined in HG-induced HUVECs with inhibitors targeting the mitogen-activated protein kinase (MAPK) signaling pathway. HG induced the expression of the adhesion molecules ICAM-1 and VCAM-1. Pretreatment with ramipril drastically inhibited ICAM-1 and VCAM-1 production in a time- and dose-dependent manner. Moreover, upon investigating the effects of ramipril on the MAPK/extracellular signal-regulated kinase (ERK) signaling pathway, we found that ramipril completely inhibited HG-induced phosphorylation of ERK1/2. ERK inhibitors completely prevented the inhibitory effect of HG. This study demonstrated that ramipril reduces HG-stimulated induction of ICAM-1 and VCAM-1 expression via MAPK signaling, which may be useful for inhibition of atherosclerosis.

Angio-Vasculogenic Properties of Endothelial-Induced Mesenchymal Stem Cells Derived From Human Adipose Tissue

BACKGROUND Although stem cells have been regarded as a promising therapeutic option, the marginal therapeutic effects of stem cells are limitations that must be overcome for the development of effective cell therapy. This study sought to identify the angio-vasculogenic properties of endothelial differentiated mesenchymal stem cells (MSCs) and to determine whether these cells are effective for vascular repair. METHODSANDRESULTS Adipose MSCs were cultured for 10 days under endothelial cell (EC) culture conditions. These endothelial cell differentiated adipose MSCs (EA) and undifferentiated adipose MSCs (UA) were characterized via angiogenesis and adhesion assays. These cells were transplanted into a hindlimb ischemia (HLI) model to determine therapeutic effects and their underlying mechanisms. EA displayed low adhesion and angiogenic properties in vitro compared with UA. When implanted into mouse HLI models, EA exhibited the decreased recovery of blood perfusion in limb ischemia than uncultured UA. Histology data showed that injected EA exhibited lower retention, angiogenic cytokine levels, and neovascularization in vivo than did UA. Short-term differentiated EA display less cell engraftment and angio-vasculogenic potential, and are less effective for peripheral vascular repair than UA. CONCLUSIONS EC differentiation of MSCs may not present an effective strategy for the promotion of therapeutic neovascularization.

The relationship between circulating neutrophil gelatinase-associated lipocalin and early alteration of metabolic parameters is associated with dietary saturated fat intake in non-diabetic Korean women

Circulating neutrophil gelatinase-associated lipocalin (NGAL) is associated with obesity-related metabolic disorders. This study investigated the relationship between serum NGAL and early alteration of metabolic parameters in non-diabetic Korean women, particularly with respect to saturated fat (SFA) intake. Anthropometric parameters, fasting glycemic status, and levels of lipids, oxidative stress/inflammatory markers, and NGAL were measured in 82 non-diabetic Korean women [Super-healthy group (n=57) with 0 metabolic syndrome risk factor (MetS RF) and MetS-risk group (n=25) with MetS RF≥1]. Age, weight, waist circumference, blood pressure, fasting glucose, HbA1C, triglyceride, LDL and total-cholesterol, and NGAL levels were higher, and HDL-cholesterol was lower in the MetS-risk group than in the Super-healthy group. Age-adjusted serum NGAL levels were higher in the MetS-risk group than in the Super-healthy group. NGAL increased proportionally with increase in MetS RFs (p=0.038) and correlated positively with BMI, triglycerides, LDL- and total-cholesterol, interleukin-6, white blood cell count, and neutrophil%, and negatively with HDL-cholesterol and superoxide dismutase activity. Serum NGAL levels positively correlated with SFA intake before and after adjustment (age and BMI). Serum NGAL levels were higher in high-SFA consumers [≥7g/day, ≥7% of total calorie intake (TCI)] than in low-SFA consumers (<7g/day, <7% of TCI). Serum NGAL levels were highest in the MetS-risk group consuming higher SFA and lowest in the Super-healthy group consuming lower SFA. However, serum NGAL did not significantly differ between the low-SFA consuming MetS-risk and Super-healthy groups. The relationship between circulating NGAL and early alteration of metabolic parameters is associated with dietary SFA intake in non-diabetic Korean women.

Glycated Hemoglobin is a Better Predictor than Fasting Glucose for Cardiometabolic Risk in Non-diabetic Korean Women

This study aimed to investigate if glycated hemoglobin (HgbA1C) as compared to fasting blood glucose is better for reflecting cardiometabolic risk in non-diabetic Korean women. Fasting glucose, HgbA1C and lipid profiles were measured in non-diabetic women without disease (n = 91). The relationships of fasting glucose or HgbA1C with anthropometric parameters, lipid profiles, and liver and kidney functions were analyzed. Both fasting glucose and HgbA1C were negatively correlated with HDL-cholesterol (r = -0.287, p = 0.006; r = -0.261, p = 0.012), and positively correlated with age (r = 0.202, p = 0.008; r = 0.221, p = 0.035), waist circumference (r = 0.296, p = 0.005; r = 0.304, p = 0.004), diastolic blood pressure (DBP) (r = 0.206, p = 0.050; r = 0.225, p = 0.032), aspartate transaminase (AST) (r = 0.237, p = 0.024; r = 0.368, p < 0.0001), alanine transaminase (ALT) (r = 0.296, p = 0.004; r = 0.356, p = 0.001), lipid profiles including triglyceride (r = 0.372, p < 0.001; r = 0.208, p = 0.008), LDL-cholesterol (r = 0.315, p = 0.002; r = 0.373, p < 0.0001) and total cholesterol (r = 0.310, p = 0.003; r = 0.284, p = 0.006). When adjusted for age and body mass index, significant relationships of DBP (r = 0.190, p = 0.049), AST (r = 0.262, p = 0.018), ALT (r = 0.277, p = 0.012), and HDL-cholesterol (r = -0.202, p = 0.049) with HgbA1C were still retained, but those with fasting glucose disappeared. In addition, the adjusted relationships of LDL-cholesterol and total cholesterol with HgbA1C were much greater than those with fasting glucose. These results suggest that glycated hemoglobin may be a better predictor than fasting glucose for cardiometabolic risk in non-diabetic Korean women.

CD31(+) cell transplantation promotes recovery from peripheral neuropathy.

Recently, we reported that human peripheral blood (PB)-derived CD31(+) cells are highly angiogenic. In this study, we investigated the beneficial effects of CD31(+) cells on peripheral neuropathy in mice. CD31(+) cells were collected from the peripheral blood using magnetic activated cell sorting. CD31(+) cells exhibited higher levels of expression of angiogenic genes on real-time reverse transcriptase polymerase chain reaction. Peripheral neuropathy was induced by crushing the sciatic nerve with a hemostat, and CD31(+) cells were then injected intramuscularly along the sciatic nerve. CD31(+) cell transplantation restored motor nerve conduction velocity and voltage amplitude and improved motor coordination. In addition, CD31(+) cell transplantation significantly improved blood perfusion and increased intraneural vascularity in the sciatic nerve. Whole-mount fluorescent imaging and dot blot analysis showed that CD31(+) cells in the nerve possessed high engraftment and anti-apoptotic properties. Additionally, injected CD31(+) cells displayed neurovascular tropism and are highly incorporated with vasculature. Angiogenic cytokines were augmented in CD31(+)-injected nerve tissue, suggesting increased neovascularization. Taken together, these results indicate that CD31(+) cells might be a novel therapeutic strategy in the treatment of peripheral neuropathy.

Human adipose mesenchymal stem cells overexpressing dual chemotactic gene showed enhanced angiogenic capacity in ischaemic hindlimb model

Aims In present study, we sought to characterize the angio-vasculogenic property of human adipose mesenchymal stem cells (ASCs) overexpressing dual chemokine GCP-2 and SDF-1α (ASC-G/S) and to determine the therapeutic potential of ASC-G/S in the context of experimental ischaemia. Methods and results We generated ASC-G/S line and performed flow cytometry, quantitative (q)-PCR, Matrigel tube formation, Matrigel plug assays, and in vivo therapeutic assays using hind limb ischaemia mouse model. Q-PCR results showed that the representative pro-angiogenic factors were highly upregulated in ASC-G/S compared with ASCs single chemokine overexpressing GCP-2 (ASC-G). In addition, ASC-G/S exhibited high expression of endothelium-specific genes shch as vWF and Flk-1 and showed robust in vitro micro-vascular formation. ASC-G/S was transplanted into ischaemic mouse hind limbs and compared with control groups. ASC-G/S injection prevented limb loss and augmented blood perfusion, suggesting that ASC-G/S enhances neovascularization in hind limb ischaemia. In addition, transplanted ASC-G/S revealed high vasculogenic potential in vivo compared with transplanted ASC-G. Conclusion Our data suggest that ASC-G/S has high therapeutic effects on hind limb ischaemia via robust angiogenic and vasculogenic action.