Increased serum concentrations of asymmetric dimethylarginine (ADMA) in patients with early-onset coronary artery disease.

BACKGROUND: Asymmetric dimethylarginine (ADMA) has been associated with an increased risk of cardiovascular disease. We investigated the role of serum ADMA concentrations in early-onset coronary artery disease (EOCAD). METHODS: Candidates for coronary artery angiography (age<50y for men and <55y for women) who met the inclusion criteria were enrolled in this study. Serum concentrations of ADMA were determined using ELISA. Severity of coronary atherosclerosis was estimated by number of diseased vessels. RESULTS: A total of 601 subjects (286 with EOCAD patients and 315 controls) were included in the study. ADMA concentrations were found to be significantly higher in the EOCAD group (0.480±0.110µmol/l) than in the control group (0.457±0.091, P=0.007). ADMA concentrations significantly increased with the number of diseased vessels (P<0.001). In addition, serum ADMA concentrations were affected by diabetes mellitus and smoking status, and were positively correlated with serum creatinine and body mass index (BMI). CONCLUSIONS: Our results show that serum ADMA concentrations were associated with the presence and severity of EOCAD, suggesting that ADMA may be involved in the progression of EOCAD.

Mitochondrial membrane potential and reactive oxygen species in cancer stem cells.

Cancer stem cells (CSCs) are believed as the initiators of the occurrence, development and recurrence of malignant tumors. Targeting this unique cell population would provide a less toxic approach than regular chemotherapeutic agents that kill bulk rapid proliferating tumor cells and also normal cells which divide rapidly. To date, major research effort has been aimed at identifying and eradicating CSC population. The metabolism heterogeneity of mitochondria in CSCs shows a big promise for cancer research. Of them, mitochondrial membrane potential (Δψm), reflecting the functional status of the mitochondrion is proved to be highly related to cancer malignancy. Reactive oxygen species, mainly produced from mitochondria, are also increased in many types of cancer cells. However, their statuses in CSCs remain poorly understood. Here we shall review the mitochondrial membrane potential and reactive oxygen species of CSCs and propose the novel potential targets for cancer therapy.

Berberine ameliorates renal injury in streptozotocin-induced diabetic rats by suppression of both oxidative stress and aldose reductase.

BACKGROUND: Berberine is one of the main constituents of Coptidis rhizoma (CR) and Cortex phellodendri. In this study, we investigated the beneficial effects of berberine on renal function and its possible mechanisms in rats with diabetic nephropathy (DN). METHODS: Male Wistar rats were divided into three groups: normal, diabetic model, and berberine treatment groups. Rats in the diabetic model and berberine treatment groups were induced to diabetes by intraperitonal injection with streptozotocin (STZ). Glomerular area, glomerular volume, fasting blood glucose (FBG), blood urea nitrogen (BUN), serum creatinine (Cr) and urine protein for 24 hours (UP24h) were measured using commercially available kits. Meanwhile, the activity of superoxide dismutase (SOD), content of malondialdehyde (MDA) in serum, activity of aldose reductase (AR) and the expression of AR mRNA and protein in kidney were detected by different methods. RESULTS: The results showed that oral administration of berberine (200 mg x kg(-1) x d(-1)) significantly ameliorated the ratio of kidney weight to body weight. Glomerular area, glomerular volume, FBG, BUN, Cr and UP24h were significantly decreased in the berberine treatment group compared with the diabetic model group (P < 0.05). Berberine treatment significantly increased serum SOD activity and decreased the content of MDA compared with diabetic model group (P < 0.05). AR activity as well as the expression of AR mRNA and protein in the kidney was markedly decreased in the berberine treatment group compared with diabetic model group (P < 0.05). CONCLUSION: These results suggested that berberine could ameliorate renal dysfunction in DN rats through controlling blood glucose, reduction of oxidative stress and inhibition of the activation of the polyol pathway.

[A pilot study on transdifferentiation of skin stem cell in reconstructing corneal epithelium].

OBJECTIVE: To observe the differentiation and development of skin stem cells on corneal stroma and to discuss the possibility of reconstructing corneal epithelium with skin stem cells. METHODS: Pieces of human and rabbit skin were obtained during operation. Rabbit eye balls were taken, and pieces of corneal stroma without epithelium were prepared. Skin stem cells from the rabbit skin and human skin were cultured. The human skin stem cells of the first generation to 4th generation were implanted on the rabbit corneal stroma and cultured. Three rabbits underwent autotransplantation of the rabbit skin stem cells of the first generation to 4th generation on the pieces of corneal stroma with the superficial lamina removed and then fed for 100 approximately 114 days. Another 3 rabbits underwent allotransplantation of the rabbit skin stem cells of first to 4th generation on the pieces of corneal stroma with the superficial lamina removed and then fed for 100 days. Then the rabbits were killed and their eye balls taken out. The rabbit corneas implanted with human or rabbit epithelial cells and the rabbit corneas with the autogeneous or heterogeneous epithelial cells were sliced and underwent immunohistochemistry with human AE5 antibody corresponding to the specific surface marker keratin K3/K12 common to humankind and rabbit, and human epithelial cell keratin K-19 monoclonal antibody. RESULTS: Since the 3(rd) day of transplantation the transplanted human epithelial cells formed multiplayer and were human AE5 antibody and human K19 monoclonal antibody positive. The autotransplanted corneas remained basically transparent without obvious vascular hyperplasia till the cornea specimens were taken. Histological examination showed intact multiplayer epithelium and immunohistochemistry showed human AE5 positive. The allotransplanted\rabbit corneas showed congestion since the 9(th) day. Histological examination showed that the corneas were nor so transparent as the autotransplanted ones and the epithelium was nor intact with a lot of lymphocyte infiltration. CONCLUSION: Corneal epithelium can be reconstructed from skin stem cell, which may be an alternative for constructing autogeneous bioengineered corneas.

[Experimental study on promoting the engraftment of hematopoietic stem/progenitor cell by all-trans retinoic acid].

OBJECTIVE: To explore the effect of all-trans retinoic acid (RA) on the engraftment of unrelated umbilical cord blood stem/progenitor cell transplantation (UCBT) in murine model. METHODS: 1 x 10(6) and 0.5 x 10(6) nucleated cells (NC) from C57BL/6 (H-2(b)) fetal and neonatal peripheral blood (FNPB) were separately transfused into lethally cyclophosphamide (380 mg/kg, ip) treated BALB/C (H-2(d)) recipients, 15 mg.kg(-1).d(-1) and 5 mg.kg(-1).d(-1) RA (15 mg and 5 mg RA) were administrated respectively 2 days before and after UCBT. Hematopoiesis and immune recovery, graft versus host disease (GVHD), engraftment and survival rates were then observed. RESULTS: Hematopoiesis and immune recovery occurred faster in RA treated than in untreated mice (P < 0.05). Acute GVHD was absent. The levels of engraftment were higher in both 15 mg and 5 mg RA treated mice than those in untreated controls (P < 0.05). In 1 x 10(6) NC transfused mice, 15 mg and 5 mg RA could significantly increased the 30 and 60 days survival rates from 41.67% (without RA) to 72.23% and 70.83%, respectively (P < 0.05). In 0.5 x 10(6) cells transfused mice, 15 mg and 5 mg RA increased the survival rate from 14.29% (without RA) to 42.86% and 43.48%, respectively (P < 0.05), which were comparable to that of being transfused 1 x 10(6) cells without RA treatment (P > 0.05). CONCLUSION: RA enhances the engraftment of umbilical cord blood stem/progenitor cells in murine model for UCBT. This might provide an experimental evidence of RA in clinical UCBT.

[Establishment of a murine model for allogeneic umbilical cord blood transplantation].

This study was undertaken to establish a murine model for unrelated allogeneic umbilical cord blood transplantation (UCBT). The characteristics and percentage of hematopoietic stem/progenitor cells between near-term fetal and neonatal murine peripheral blood (FNPB) and bone marrow (BM) were evaluated by flow cytometry and semisolid methylcellulose culture. BABL/c (H-2(d)) recipient mice conditioned with high dose CTX were transplanted with FNPB form C57BL/6 (H-2(b)) mice and the survival rate, hematopoietic and immunological reconstruction, graft versus host disease (GVHD) and engraftment level were observed. The results showed that the numbers of day 14 CFU-GM and CFU-GEMM in FNPB (176.40 +/- 78.39)% and (141.40 +/- 56.57)%, respectively were much higher than those in BM (75.20 +/- 26.41)% and (68.80 +/- 23.95)%, respectively. Moreover the percentage of Sca-1(+) CD34(+) cell subsets in FNPB (3.63 +/- 1.13)% was also higher than that in BM (1.41 +/- 0.8 7)%. FNPB transplantation improved survival rate and reconstituted hematopoietic and immune function in recipients. There was no evidence of GVHD. Chimeric analysis showed that the proportion of donor cells in BM of recipients was 27.94% at 21 days after transplantation. It was concluded that FNPB contains more hematopoietic stem and progenitor cells with high expansion ability and weak allogeneic immunity, which was similar to human UCB. The murine model for allogeneic UCBT (C57BL/6-->BALB/c) was established successfully.