Gold Nanoparticles Using Ecklonia stolonifera Protect Human Dermal Fibroblasts from UVA-Induced Senescence through Inhibiting MMP-1 and MMP-3.

The effect of gold nanoparticles (GNPs) synthesized in marine algae has been described in the context of skin, where they have shown potential benefit. Ecklonia stolonifera (ES) is a brown algae that belongs to the Laminariaceae family, and is widely used as a component of food and medicine due to its biological activities. However, the role of GNPs underlying cellular senescence in the protection of Ecklonia stolonifera gold nanoparticles (ES-GNPs) against UVA irradiation is less well known. Here, we investigate the antisenescence effect of ES-GNPs and the underlying mechanism in UVA-irradiated human dermal fibroblasts (HDFs). The DPPH and ABTS radical scavenging activity of ES extracts was analyzed. These analyses showed that ES extract has potent antioxidant properties. The facile and optimum synthesis of ES-GNPs was established using UV-vis spectra. The surface morphology and crystallinity of ES-GNPs were demonstrated using high resolution transmission electron microscopy (HR-TEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR). ES-GNPs presented excellent photocatalytic activity, as shown by the photo-degradation of methylene blue and rhodamine B. A cellular senescence model was established by irradiating HDFs with UVA. UVA-irradiated HDFs exhibited increased expression of senescence-associated ß-galactosidase (SA-ß-galactosidase). However, pretreatment with ES-GNPs resulted in reduced SA-ß-galactosidase activity in UVA-irradiated HDFs. Intracellular ROS levels and G1 arrest in UVA-irradiated HDFs were checked against the background of ES-GNP treatment to investigate the antisenescence effects of ES-GNPs. The results showed that ES-GNPs significantly inhibit UVA-induced ROS levels and G1 arrest. Importantly, ES-GNPs significantly downregulated the transcription and translation of MMP (matrix metalloproteinases)-1/-3, which regulate cellular senescence in UVA-irradiated HDFs. These findings indicate that our optimal ES-GNPs exerted an antisenescence effect on UVA-irradiated HDFs by inhibiting MMP-1/-3 expression. Collectively, we posit that ES-GNPs may potentially be used to treat photoaging of the skin.

Effect of angiotensin II type 1 receptor blocker and angiotensin converting enzyme inhibitor on the intraocular growth factors and their receptors in streptozotocin-induced diabetic rats.

AIM: To investigate the effect of angiotensin II type 1 receptor blocker (ARB) and angiotensin converting enzyme inhibitor (ACEI) on intraocular growth factors and their receptors in streptozotocin-induced diabetic rats. METHODS: Forty Sprague-Dawley rats were divided into 4 groups: control, diabetes mellitus (DM), candesartan-treated DM, and enalapril-treated DM (each group, n=10). After the induction of DM by streptozotocin, candesartan [ARB, 5 mg/(kg·d)] and enalapril [ACEI, 10 mg/(kg·d)] were administered to rats orally for 4wk. Vascular endothelial growth factor (VEGF) and angiotensin II (Ang II) concentrations in the vitreous were measured using enzyme-linked immunosorbent assays, and VEGF receptor 2 and angiotensin II type 1 receptor (AT1R) levels were assessed at week 4 by Western blotting. RESULTS: Vitreous Ang II levels were significantly higher in the DM group and candesartan-treated DM group than in the control (P=0.04 and 0.005, respectively). Vitreous AT1R increased significantly in DM compared to the other three groups (P<0.007). Candesartan-treated DM rats showed higher vitreal AT1R concentration than the enalapril-treated DM group and control (P<0.001 and P=0.005, respectively). No difference in vitreous Ang II and AT1R concentration was found between the enalapril-treated DM group and control. VEGF and its receptor were below the minimum detection limit in all 4 groups. CONCLUSION: Increased Ang II and AT1R in the hyperglycemic state indicate activated the intraocular renin-angiotensin system, which is inhibited more effectively by systemic ACEI than systemic ARB.

The relationship between amniotic and newborn gastric fluid inflammatory mediators.

UNLABELLED: To determine whether the levels of inflammatory mediators in gastric fluid (GF) of a premature newborn are associated with those in amniotic fluid (AF) of the newborn's mother. PATIENTS: Twenty-three pairs of pregnant women and their premature newborns <35 weeks gestation, born by Cesarean sections. METHODS: Amniotic fluids and newborn gastric fluids were obtained from women during Cesarean section procedure. The mother-premature newborn dyads were retrospectively assessed to analyze the clinical and laboratory data. Concentrations of interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-α) and mannose-binding lectin (MBL) were compared between amniotic and newborn gastric fluids in each dyad. RESULTS: Premature newborns and their mothers with funisitis had significantly higher median AF IL-6, TNF-α and GF IL-8 concentrations than those without funisitis (p = 0.022 for AF IL-6; p = 0.023 for AF TNF-α; p = 0.022 for GF IL-8). The concentrations of IL-6, IL-8, TNF-α and MBL in newborn GF were significantly correlated with those in AF in each dyad (p < 0.001, r = 0.872 for IL-6; p < 0.001, r = 0.851 for IL-8; p < 0.001, r = 0.768 for TNF-α; p < 0.001, r = 0.845 for MBL, respectively). CONCLUSION: The levels of inflammatory mediators in GF of a premature newborn immediately after birth are strongly associated with those in AF of the newborn's mother.

Differentiation and characteristics of undifferentiated mesenchymal stem cells originating from adult premolar periodontal ligaments.

OBJECTIVE: The purpose of this study was to investigate the isolation and characterization of multipotent human periodontal ligament (PDL) stem cells and to assess their ability to differentiate into bone, cartilage, and adipose tissue. METHODS: PDL stem cells were isolated from 7 extracted human premolar teeth. Human PDL cells were expanded in culture, stained using anti-CD29, -CD34, -CD44, and -STRO-1 antibodies, and sorted by fluorescent activated cell sorting (FACS). Gingival fibroblasts (GFs) served as a positive control. PDL stem cells and GFs were cultured using standard conditions conducive for osteogenic, chondrogenic, or adipogenic differentiation. RESULTS: An average of 152.8 ± 27.6 colony-forming units was present at day 7 in cultures of PDL stem cells. At day 4, PDL stem cells exhibited a significant increase in proliferation (p < 0.05), reaching nearly double the proliferation rate of GFs. About 5.6 ± 4.5% of cells in human PDL tissues were strongly STRO-1-positive. In osteogenic cultures, calcium nodules were observed by day 21 in PDL stem cells, which showed more intense calcium staining than GF cultures. In adipogenic cultures, both cell populations showed positive Oil Red O staining by day 21. Additionally, in chondrogenic cultures, PDL stem cells expressed collagen type II by day 21. CONCLUSIONS: The PDL contains multipotent stem cells that have the potential to differentiate into osteoblasts, chondrocytes, and adipocytes. This adult PDL stem cell population can be utilized as potential sources of PDL in tissue engineering applications.

Mesenchymal stem cells derived from human adipose tissues favor tumor cell growth in vivo.

Mesenchymal stem cells (MSCs) have generated a great deal of interest in clinical situations, due principally to their potential use in regenerative medicine and tissue engineering applications. However, the therapeutic application of MSCs remains limited, unless the favorable effects of MSCs for tumor growth in vivo and the long-term safety of the clinical applications of MSCs can be understood more thoroughly. In this study, MSCs derived from human adipose tissues (hASCs) together with tumor cells were transplanted subcutaneously or intracranially into BALB/c nude mice to observe tumor outgrowth. The results indicated that hASCs with H460 or U87MG cells promoted tumor growth in nude mice. Our histopathological analyses indicated that the co-injection of tumor cells with hASCs exerted no influence on the formation of intratumoral vessels. Co-culture of tumor cells with hASCs or the addition of conditioned medium (CM) from hASCs effected an increase in the proliferation of H460 or U87MG cells. Co-injection of hASCs with tumor cells effected an increase in tumor cell viability in vivo, and also induced a reduction in apoptotic cell death. CM from hASCs inhibited hydrogen peroxide-induced cell death in H460 or U87MG cells. These findings indicated that MSCs could favor tumor growth in vivo. Thus, it is necessary to conduct a study concerning the long-term safety of this technique before MSCs can be used as therapeutic tools in regenerative medicine and tissue engineering.

Change of the expression of human telomerase reverse transcriptase mRNA and human telomerase RNA after cisplatin and 5-fluorouracil exposure in head and neck squamous cell carcinoma cell lines.

Telomerase activity appears to be associated with cell immortalization and malignant progression. Understanding how telomerase activity is regulated in vivo is important not only for understanding the molecular biology of telomerase but also for the potential clinical application of anticancer drugs. This study evaluated telomerase activity and quantified the expression of human telomerase reverse transcriptase (hTERT) mRNA and human telomerase RNA (hTR) using a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) method before and after the exposure of cisplatin and 5-fluorouracil (5-FU) in two head and neck squamous cell carcinoma (HNSCC) cell lines. Two human HNSCC cell lines (PNUH-12 and SNU-899) were studied. Cell cytotoxicity, the change of telomerase activity, and hTERT mRNA and hTR expression by 5-FU and cisplatin exposure were assessed by MTT assay, TRAP assay, and real-time RT-PCR, respectively. In two cell lines, after cisplatin exposure, the telomerase activity and hTERT mRNA expression decreased, but hTR expression in- creased according to the concentration of drug. However, in both cell lines, the telomerase activity and hTR did not show any significant change after 5-FU treatment, but the expression of hTERT mRNA decreased. These results suggest that there may be other important regulating mechanism except hTERT mRNA as the regulation factor of telomerase activity in HNSCC cell lines.

Role of Wnt5a in the proliferation of human glioblastoma cells.

Wnt5a operates as either a tumor suppressor or a tumor stimulator, according to tumor type. The functions of Wnt5a in human glioblastoma (GBM) have yet to be determined. We initially evaluated the expression of Wnt5a in human glioma. The results of immunohistochemical analyses have revealed that Wnt5a expression was higher in human GBM than in normal brain tissue and low-grade astrocytoma. In order to assess the role of Wnt5a on proliferation in human glioblastoma cells, we employed U87MG and GBM-05, a newly established GBM cell line. GBM-05 was established from a patient diagnosed with GBM. GBM-05 cells were shown to express Nestin, but did not express GFAP and Map2ab. GBM-05 cells formed infiltrating brain tumors after being intracerebrally transplanted into nude mice, and xenotransplanted GBM-05 cells were observed to differentiate into neuronal and astrocyte lineages. Wnt5a expression in the xenotransplanted tumors was higher than that detected in the surrounding brain tissues. The overexpression of Wnt5a increased the proliferation of GBM-05 and U87MG in vitro. By way of contrast, the downregulation of Wnt5a expression as the result of RNA interference reduced proliferation from GBM-05 and U87MG cells in vitro, and reduced tumorigenicity in vivo. Our data indicate that Wnt5a signaling is an important regulator in the proliferation of human glioma cells.

Expression of telomerase extends longevity and enhances differentiation in human adipose tissue-derived stromal cells.

Human bone marrow stromal cells (hBMSCs) are defined as pluripotent progenitor cells with the ability to differentiate into osteoblasts, chondrochytes, adipocytes, muscle cells, and neural cells. Recently, it has been shown that telomerase expression not only extends the replicative life-span and maintains their bone-forming capability of hBMSCs. We previously reported that human adipose tissue stromal cells (hATSCs) have similar characteristics with hBMSCs. In this study, hATSCs were stably tranduced by a retrovirus containing the gene for the catalytic subunit of human telomerase (hTERT) and MSCV-neo retrovirus, and 12 clones for hTERT-hATSCs and 6 clones for MSCV-hATSCs were isolated. The tranduced clones (hATSC-TERTs) had high telomerase activity, which was maintained during subsequent subcultivation. The transduced cells of two representative clones have undergone more than 100 population doublings (PD) and continue to proliferate, whereas control cells underwent senescence-associated proliferation arrest after 36-40 PD. The cells had a normal karyotype, and increased differentiation potential, especially osteogenic lineage. Intraventricular injection of hATSC-TERTs in ischemic rat brain showed enhancement of functional recovery as like hATSC-MSCVs. The tissue engraftment of hATSCs and hTERT-hATSCs in NOD/SCID mice after intravenous administration was identical. These results further support a similarity between hBMSCs and hATSCs. hATSCs can be used as an alternative of pluripotent stromal cells for cell replacement therapy as like hBMSCs.

Interactions between human adipose stromal cells and mouse neural stem cells in vitro.

Transplantation of adult mesenchymal stem cells (MSCs) into adult rat brain has been known to reduce functional deficits associated with stroke and traumatic brain injury. However, in injured brains, there is no evidence that transplanted MSCs replace lost host brain tissue. In this study, we determined in vitro interaction between human adipose tissue stromal cells (hATSCs), a kind of MSC, and neural stem cells (NSCs). hATSCs were isolated and proliferated from human adipose tissues, and NSCs from the subventricular zone of postnatal mice. When NSCs were cultured on mitomycin-treated hATSC monolayers, their proliferation was decreased, but neuronal differentiation was significantly induced. The percentage of neurons significantly increased in 7 days in cultures of NSCs on hATSCs feeder as compared to NSCs cultured on laminin-coated dishes. When the duration of the cultures was extended to 14 days, hATSCs supported the survival of neurons derived from NSCs. To determine the role of soluble factors from hATSCs, NSCs were cultured with hATSCs conditioned medium or co-cultured with permeable filter on which hATSCs were grown. Although proliferation of NSCs significantly decreased and glial differentiation increased under these experimental conditions, their neuronal differentiation was not affected, indicating that direct physical contact between hATSCs and NSCs is required for induction of neuronal differentiation. These data indicate that hATSCs may provide supportive roles on endogenous neural stem cells, when they are transplanted into damaged brain.