Antioxidant action of hypoxic conditioned media from adipose-derived stem cells in the hepatic injury of expressing higher reactive oxygen species

PURPOSE: Almost all liver diseases are known to be accompanied by increased levels of reactive oxygen species (ROS), regardless of the cause of the liver disorder. However, little is known about the role of hypoxic conditioned media (HCM) in the view of pro-oxidative/antioxidative balance. METHODS: Normoxic conditioned media (NCM) and HCM were obtained after culturing adipose-derived stem cells in 20% O₂ or 1% O₂ for 24 hours, respectively. Their effects on the expression of various markers reflecting pro-oxidative/antioxidative balance were investigated in both in vitro (thioacetamide-treated AML12 cells) and in vivo (partially hepatectomized mice) models of liver injury, respectively. RESULTS: HCM treatment induced the higher expression of antioxidant enzymes, such as superoxide dismutase, glutathione peroxidase, and catalase than did NCM in the in vitro model of liver injury. We also found that HCM increased the expression of nuclear factor erythroid 2-related factor (NRF2). The in vivo models of liver injury consistently validated the phenomenon of upregulated expression of antioxidant enzymes by HCM. CONCLUSION: We thus could conclude that HCM provides protection against ROS-related toxicity by increasing the expression of antioxidant enzymes, in part by releasing NRF2 in the injured liver.

Liver Regenerating Potential of the Secretome Obtained from Adipose-derived Stem Cells Cultured under the Hypoxic Environment / 대한이식학회지

BACKGROUND: The stem cell-derived secretome has received considerable attention as an alternative to stem cells for therapeutic applications. However, establishing optimal culture conditions is key to obtaining appropriate secretome contents. Here, the optimal culturing environment for achieving a high-efficiency secretome was determined via hypoxic preconditioning of human adipose-derived stem cells (ASC). METHODS: Normoxic conditioned media (NCM) and hypoxic conditioned media (HCM) were obtained after culturing human ASCs under normoxia (20% O2) or hypoxia (1% O2), respectively. Subsequently, both normal and thioacetamide-induced hepatotoxic hepatocytes were treated with NCM or HCM. In addition, partially hepatectomized mice were infused with control saline, NCM, and HCM. The effects on liver regeneration and serum transaminases levels were then compared. RESULTS: Hypoxic preconditioning significantly increased mRNA expression of proinflammatory cytokines (interleukin-6 and tumor necrosis factor-α) and growth factors (hepatocyte growth factor and vascular endothelial growth factor). In both normal and thioacetamide-induced hepatotoxic hepatocyte (alpha mouse liver 12 [AML12]) cell lines, HCM treatment resulted in the highest cell viability (122% and 95%, respectively), followed by NCM (111% and 78%, respectively). In addition, intravenous administration of HCM to partially hepatectomized mice resulted in substantially enhanced liver regeneration compared with the NCM group (P<0.05). CONCLUSIONS: Taken together, the secretome obtained from ASC with hypoxic preconditioning showed potential to alleviate liver damage both in vitro and in vivo. Hypoxic culture of ASC is expected to play an important role in regenerative medicine by inducing secretome production that is beneficial for improving liver regeneration.

Efficacy of Microneedling Plus Human Stem Cell Conditioned Medium for Skin Rejuvenation: A Randomized, Controlled, Blinded Split-Face Study

BACKGROUND: The use of growth factors in skin rejuvenation is emerging as a novel anti-aging treatment. While the role of growth factors in wound healing is well established, their use in skin rejuvenation has only recently been to be studied and no controlled trials have been performed. OBJECTIVE: We evaluated the anti-aging effects of secretory factors of endothelial precursor cells differentiated from human embryonic stem cells (hESC-EPC) in Asian skin. METHODS: A total of 25 women were included in this randomized, controlled split-face study. The right and left sides of each participant's face were randomly allocated to hESC-EPC conditioned medium (CM) or saline. To enhance epidermal penetration, a 0.25-mm microneedle roller was used. Five treatment sessions were repeated at 2-week intervals. RESULTS: Physician's global assessment of pigmentation and wrinkles after treatment revealed statistically significant effects of microneedling plus hESC-EPC CM compared to microneedling alone (p<0.05). Skin measurements by Mexameter and Visiometer also revealed statistically significant effects of microneedling plus hESC-EPC CM on both pigmentation and wrinkles (p<0.05). The only minimal adverse event was mild desquamation in one participant. CONCLUSION: Secretory factors of hESC-EPC improve the signs of skin aging and could be a potential option for skin rejuvenation.