Therapeutic trial of hematological disorders with intermittent administration of high-dose 1-alpha-hydroxyvitamin D3

Aplastic anemia and myelodysplastic syndrome were successfully treated with an intermittent administration of high-dose 1 alpha-hydroxy-vitamin D3, an active analogue of 1,25-dihydroxyvitamin D3. This effect was considered to be through the differentiation-inducing and immunomodulatory actions of 1,25-dihydroxyvitamin D3. The only adverse effect was hypercalciuria which was controllable by decreasing the dose.

DNA aptamer raised against advanced glycation end products (AGEs) improves glycemic control and decreases adipocyte size in fructose-fed rats by suppressing AGE-RAGE axis

Advanced glycation end products (AGEs) decrease adiponectin expression and suppress insulin signaling in cultured adipocytes through the interaction with a receptor for AGEs (RAGE) via oxidative stress generation. We have recently found that high-affinity DNA aptamer directed against AGE (AGE-aptamer) prevents the progression of experimental diabetic nephropathy by blocking the harmful actions of AGEs in the kidney. This study examined the effects of AGE-aptamer on adipocyte remodeling, AGE-RAGE-oxidative stress axis, and adiponectin expression in fructose-fed rats. Although AGE-aptamer treatment by an osmotic mini pump for 8 weeks did not affect serum insulin levels, it significantly decreased average fasting blood glucose and had a tendency to inhibit body weight gain in fructose-fed rats. Furthermore, AGE-aptamer significantly suppressed the increase in adipocyte size and prevented the elevation in AGEs, RAGE, and an oxidative stress marker, 8-hydroxydeoxyguanosine (8-OHdG), levels in adipose tissues of fructose-fed rats at 14-week-old, while it restored the decrease in adiponectin mRNA levels. Our present study suggests that AGE-aptamer could improve glycemic control and prevent adipocyte remodeling in fructose-fed rats partly by suppressing the AGE-RAGE-mediated oxidative stress generation. AGE-aptamer might be a novel therapeutic strategy for fructose-induced metabolic derangements.

Bazedoxifene blocks AGEs-RAGE-induced superoxide generation and MCP-1 level in endothelial cells

Advanced glycation endproducts (AGEs) and their receptor (RAGE) play a role in vascular complications in diabetes. We have previously shown that 17β-estradiol at 10 nmol/l, a nearly identical plasma concentration to that during mid-pregnancy, up-regulates RAGE expression in endothelial cells. The finding might suggest the involvement of 17β-estradiol in the deterioration of vascular complications in diabetes during pregnancy. However, the effects of the selective estrogen receptor modulator, bazedoxifene, on oxidative and inflammatory reactions in AGEs-exposed endothelial cells remain unknown. In this study, we addressed the issue. Ten nmol/l 17β-estradiol increased RAGE and monocyte chemoattractant protein-1 (MCP-1) gene and protein expression in human umbilical vein endothelial cells (HUVECs), both of which were blocked by 10 nmol/l bazedoxifene. Bazedoxifene at 10 nmol/l also significantly inhibited the AGEs-induced superoxide generation, RAGE and MCP-1 gene and protein expression in HUVECs. The present study suggests that blockade of the AGEs-RAGE axis by bazedoxifene might be a novel therapeutic target for preventing vascular damage in diabetes, especially in postmenopausal women.

Effects of supplemental oxygen on urinary 8-hydroxy-2'-deoxyguanosine levels in extremely low birth weight infants

As the effects of supplementary oxygen on urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG) are poorly understood, urinary 8-OHdG levels (ng/mg creatinine) were determined longitudinally on the postnatal day (PND) 1, 3, and 30 in 16 neonates with birth weight < 1000 g. No supplementary oxygen was required in 9 neonates during the first 24 h of life. Urinary 8-OHdG level on PND 1 was inversely correlated with birth weight in these 9 neonates (P = 0.0323) and was higher in four with birth weight < 750 g than five with birth weight > 750 g (41.0 ± 6.9 vs. 5.6 ± 2.7, respectively, P = 0.0200). Median urinary 8-OHdG on PND 1 of these 9 neonates was significantly lower than that of 7 neonates with oxygen (9.3 vs. 60.2, respectively), although there were no significant differences in clinical background, such as birth weight, between the two groups. Five of the 9 did not require supplemental oxygen at all during the first 30 days of life. Median urinary 8-OHdG levels were consistently significantly lower in the 5 neonates than in 11 neonates with oxygen transiently or persistently (9.3 vs. 54.6, 19.1 vs. 61.4, and 28.3 vs. 145 on PND 1, 3, and 30, respectively), although there were no differences in clinical background, such as birth weight, between the two groups. Urinary 8-OHdG on PND 30 was significantly positively correlated with supplemental oxygen dose on PND 30 (P < 0.0001), but not with birth weight in the 16 neonates. These results suggest that higher supplemental oxygen tension caused higher urinary 8-OHdG in this population.

Linagliptin blocks renal damage in type 1 diabetic rats by suppressing advanced glycation end products-receptor axis

Advanced glycation end products (AGEs) and their receptor (RAGE) play a role in diabetic nephropathy. We have recently found that linagliptin, an inhibitor of dipeptidyl peptidase-4 (DPP-4) suppresses the AGE-induced oxidative stress generation and intercellular adhesion molecule-1 (ICAM-1) gene expression in endothelial cells. However, whether linagliptin could have beneficial effects on experimental diabetic nephropathy in a glucose-lowering independent manner remains unknown. To address the issue, this study examined the effects of linagliptin on renal damage in streptozotocin-induced diabetic rats. Serum levels of DPP-4 were significantly elevated in diabetic rats compared with control rats. Although linagliptin treatment for 2 weeks did not improve hyperglycemia in diabetic rats, linagliptin significantly reduced AGEs levels, RAGE gene expression, and 8-hydroxy-2'-deoxyguanosine, a marker of oxidative stress in the kidney of diabetic rats. Furthermore, linagliptin significantly reduced albuminuria, renal ICAM-1 mRNA levels, and lymphocyte infiltration into the glomeruli of diabetic rats. Our present study suggests that linagliptin could exert beneficial effects on diabetic nephropathy partly by blocking the AGE-RAGE-evoked oxidative stress generation in the kidney of streptozotocin-induced diabetic rats. Inhibition of DPP-4 by linagliptin might be a promising strategy for the treatment of diabetic nephropathy.

Vitamin C nutrition in cattle

Domestic animals, including ruminants, can synthesize vitamin C (VC) in their liver; as such, the dietary requirement for VC has not been confirmed in these animals. The adequacy of VC has been evaluated by quantifying VC levels in plasma, but the reported values in bovine plasma have been widely variable. Plasma VC concentration is decreased by heat stress, hepatic lesions, fattening, and infectious diseases such as mastitis in cattle. Therefore, VC supplementation is potentially beneficial for cattle with low plasma VC concentration. This review discusses the methods for determination of plasma VC concentration in cattle, VC nutrition, and the efficacy of VC supplementation in calves, dairy cattle, and beef cattle. Additionally I propose a reference range for plasma VC concentration in Japanese Black cattle.

Olmesartan blocks advanced glycation end products-induced vcam-1 gene expression in mesangial cells by restoring Angiotensin-converting enzyme 2 level

Advanced glycation end products (AGEs) and their receptor (RAGE) system are involved in diabetic nephropathy. Angiotensin-converting enzyme 2 (ACE 2) plays a protective role against cardiovascular and renal injury by stimulating the production of angiotensin-(1-7) [Ang-(1-7)], an antagonist of angiotensin II (Ang II). However, effects of the AGEs-RAGE axis on ACE 2 expression in mesangial cells remain unknown. We examined here the role of ACE 2 in the AGEs-RAGE-induced mesangial cell damage and investigated whether olmesartan, one of the Ang II type 1 receptor blockers (ARB), prevented the deleterious effects of AGEs via restoration of ACE 2 and Ang-(1-7) level. AGEs significantly increased superoxide generation, upregulated RAGE mRNA level, and decreased ACE 2 gene expression and Ang-(1-7) production in mesangial cells, all of which were blocked by olmesartan, but not by a different type of ARB, azilsartan. An antioxidant, N-acetylcysteine or RAGE-antibodies also restored the decrease in ACE 2 mRNA level in AGEs-exposed mesangial cells. Moreover, olmesartan, but not azilsartan completely inhibited the AGEs-induced increase in vascular cell adhesion molecule-1 (VCAM-1) mRNA level in mesangial cells, which was abolished by the treatment with A-779, an antagonist of Ang-(1-7) receptor, Mas receptor. Our present study suggests that olmesartan could block the AGEs-induced VCAM-1 gene induction in mesangial cells by restoring the downregulated ACE 2 levels and subsequently stimulating the Ang-(1-7)-Mas receptor axis. Restoration of ACE 2 levels and blockade of renin-angiotensin system by olmesartan might be a promising strategy for the treatment of diabetic nephropathy.

Impact of assimilated and interactive aerosol on tropical cyclogenesis

This article investigates the impact of Saharan dust on the development of tropical cyclones in the Atlantic. A global data assimilation and forecast system, the NASA GEOS-5, is used to assimilate all satellite and conventional data sets used operationally for numerical weather prediction. In addition, this new GEOS-5 version includes assimilation of aerosol optical depth from the Moderate Resolution Imaging Spectroradiometer. The analysis so obtained comprises atmospheric quantities and a realistic 3-D aerosol and cloud distribution, consistent with the meteorology and validated against Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation and CloudSat data. These improved analyses are used to initialize GEOS-5 forecasts, explicitly accounting for aerosol direct radiative effects and their impact on the atmospheric dynamics. Parallel simulations with/without aerosol radiative effects show that effects of dust on static stability increase with time, becoming highly significant after day 5 and producing an environment less favorable to tropical cyclogenesis.

Association of a single nucleotide polymorphism in the SH2D1A intronic region with systemic lupus erythematosus

SH2D1A, also known as signaling lymphocytic activation molecule (SLAM)-associated protein (SAP), is an adaptor protein. Recently, it was reported that SAP deficient mice were protected from systemic lupus erythematosus (SLE). In this study, we postulated SH2D1A gene to be a candidate susceptibility gene for SLE and analyzed its association with SLE. A case-control association study was conducted on 5 tag single nucleotide polymorphisms (SNPs) in SH2D1A region in 506 Japanese female SLE patients and 330 healthy female controls. The luciferase assay was performed to determine the functional role of the SNP associated with SLE. One SNP in the intron 2, rs2049995, showed association with SLE (p=0.0110, odds ratio (OR) 1.97, 95% confidence interval (CI) 1.16-3.34, under the dominant model). The association of rs2049995 seemed to be stronger in the subset with the age of onset less than 20 years (p=0.0067, OR 2.65, 95% CI 1.28-5.46). Functional evaluation of rs2049995 showed that reporter gene activity was increased 1.9-fold for the susceptible allele compared with the resistant allele. An intronic SNP of SH2D1A is associated with SLE.