In Vitro and In Vivo Antiglycation Effects of Connarus ruber Extract.

Accumulation of advanced glycation end products (AGEs) of the Maillard reaction has been implicated in the pathogenesis of diabetes and its complications. Connarus ruber has been used as a folk remedy for several diseases, including diabetes; however, its underlying mechanism has not yet been investigated. This study investigated the effects of C. ruber extract against glycation on collagen-linked AGEs in vitro and streptozotocin-induced diabetic rats (STZ-DM rats) in vivo. The antiglycation activities of C. ruber extract and aminoguanidine (AG) were examined using a collagen glycation assay kit. Nonfluorescent AGE, Nε-carboxymethyl lysine (CML), Nω-carboxymethyl arginine, and Nε-carboxyethyl lysine levels were measured via electrospray ionization-liquid chromatography-tandem mass spectrometry. The effect of the extract on the cytotoxicity of methylglyoxal (MG), a precursor of AGEs, was examined in HL60 cells. STZ-DM rats were treated with the extract for 4 wk, and the effect was assessed using biochemical markers in the serum and CML-positive cells in renal tissues. C. ruber extract dose-dependently inhibited the glycation of collagen and formation of nonfluorescent AGEs, which was comparable to AG, and it significantly attenuated MG-induced cytotoxicity in HL60 cells. Furthermore, the glycated albumin levels in STZ-DM rats decreased, the increase in serum lipid levels was reversed, and immunohistochemistry demonstrated that CML deposition in the glomerulus of STZ-DM rats significantly decreased. Although further studies are needed, C. ruber could be a potential therapeutic for preventing and progressing many pathological conditions, including diabetes.

Deferasirox reduces oxidative stress in patients with transfusion dependency.

BACKGROUND: Iron chelation therapy is useful against the over-accumulation of iron and is expected to reduce oxidative stress resulting from the Fenton reaction and Haber-Weiss reaction. We monitored oxidative status and serum ferritin levels after in vivo administration of deferasirox (DFS) and studied the in vitro effects of iron chelators on neutrophil function. METHODS: Nine patients suffering from transfusion dependency were recruited for this study, and derivatives of reactive oxygen metabolite (dROM) tests to detect serum hydroperoxide levels were evaluated in addition to serum ferritin levels. Human neutrophil reactive oxygen species (ROS) production was determined with flow cytometry. RESULTS: Ferritin levels decreased after DFS treatment (P = 0.068), and a significant reduction in dROM levels was measured (P = 0.031). Fifty microM DFS significantly inhibited ROS production induced by fMLP in vitro (P < 0.0001), and tended to inhibit that induced by PMA. On the other hand, deferioxamine failed to inhibit ROS production even at high concentrations. CONCLUSIONS: In vivo administration of DFS resulted in the reduction of oxidative stress, and this effect was considered to depend not only on a reduction in iron storage but also on the ability of DFS to inhibit neutrophil ROS production in vitro at clinically relevant plasma levels. Further studies are needed to examine the effects of iron chelators.

[Laboratory medicine for blood transfusion and transplantation medicine].

We discussed the usefulness of routine technologies of laboratory medicine in blood transfusion and transplantation medicine. New parameters that can be measured by automated hematology analyzers have been clinically evaluated and proven to be useful so far. Based on our experience, detection systems for fragmented red cells (FRC), immature platelets (immature platelet function, IPF), and hematopoietic progenitor cells (HPC) are useful for the diagnosis of thrombotic microangiopathy, differential diagnosis of thrombocytopenia, and decision regarding the optimal timing to collect peripheral stem cells, respectively. Moreover, IPF were suggested to be an indicator of the platelet transfusion requirement. The establishment of non invasive assaying technology has been eagerly anticipated. We evaluated a hemoglobin measurement tool, and revealed that it might be applicable in predeposited, autologous blood donation. Some adverse transfusion reactions are related to neutrophil activation. Thus, we investigated the effects of serum from patients and blood donors, in the context of adverse reactions, on adhesion molecule expressions of neutrophils from volunteers using flow-cytometry. This kind of simple technology is expected to be useful in future studies to clarify the mechanisms and prevent adverse reactions.

[Evaluation of a non-invasive hemoglobin measurement device for pre-deposited autologous blood donation].

A non-invasive hemoglobin measurement instrument (Sysmex Co.Ltd., Kobe, Japan) was used for the evaluation of hemoglobin levels just before blood drawing for repeat autologous blood donation. There was a statistically significant correlation (r = 0.598) between the hemoglobin levels determined with the non-invasive instrument (NINV-Hb) and true Hb levels (T-Hb) evaluated by direct analysis with automatic hematology analyzer, KX-21 (Sysmex). The analysis used 156 data obtained from 66 patients. Ten patients whose differences between NINV-Hb and T-Hb of the first blood donation were more than 2.1 g/dl were excluded from further analysis. Imaging analysis indicated difficulties with the detection of appropriate blood vessel images in one of these patients, but the reasons for other patients were not apparent. There was a closer relationship between NINV-Hb and T-Hb for the 76 measurements for the second or third blood donation obtained from 56 patients (r = 0.704) than for the entire data (r = 0.598). When 12 g/dl was used as the cut off value for NINV-Hb, sensitivity and specificity for the detection of 1l g/dl of T-Hb, which is considered the critical level for drawing autologous blood for donation, were 83.6% and 77.8%, respectively. We conclude, therefore, that NINV-Hb evaluation can be expected to be useful for repeated autologous blood donation of limited patients, however, it is strongly expected to develop a new system having more sensitive and accurately detectable ability.