INTERMITTENT HYPOXIA-INDUCED RENAL ANTIOXIDANTS AND OXIDA- TIVE DAMAGE IN MALE MICE: HORMETIC DOSE RESPONSE

Obstructive sleep apnea causes cardiovascular disease via chronic intermittent hypoxia (IH), which may be related to oxidative stress. Nuclear factor-erythroid 2-related factor 2 (Nrf2) is an important cellular defense mechanism against oxidative stress by regulating its down-stream multiple antioxidants. The present study was to define whether IH can induce renal pathogenic damage and if so, whether Nrf2 and its down-stream antioxidants are involved in IH-induced pathogenic changes. Mice were culled for exposure to inter- mittent air as control or IH that consisted of 20.9% O2/ 8% O2 FIO2 alternation cycles (30 episodes per h) with 20 seconds at the nadir FIO2 for 12 h a day during daylight. Short term IH exposure (3 – 7 days) induced significant increases in renal inflammatory response and antioxidant levels along with a reduction of the spontaneous content of mal- ondialdehyde while long-term IH exposure (8 weeks) induced a significant decrease of antioxidant levels and significant increases of renal inflammation, oxidative damage, cell death, and fibrosis. This study suggests that IH induces a hormetic response, i.e.: short term IH exposure is able to induce a protective response to protect the kidney from oxidative damage while long-term IH exposure is able to induce a damage effect on the kidney

Notch1 Pathway Protects against Burn-Induced Myocardial Injury by Repressing Reactive Oxygen Species Production through JAK2/STAT3 Signaling

Oxidative stress plays an important role in burn-induced myocardial injury, but the cellular mechanisms that control reactive oxygen species (ROS) production and scavenging are not fully understood. This study demonstrated that blockade of Notch signaling via knockout of the transcription factor RBP-J or a pharmacological inhibitor aggravated postburn myocardial injury, which manifested as deteriorated serum CK, CK-MB, and LDH levels and increased apoptosis in vitro and in vivo. Interruption of Notch signaling increased intracellular ROS production, and a ROS scavenger reversed the exacerbated myocardial injury after Notch signaling blockade. These results suggest that Notch signaling deficiency aggravated postburn myocardial injury through increased ROS levels. Notch signaling blockade also decreased MnSOD expression in vitro and in vivo. Notably, Notch signaling blockade downregulated p-JAK2 and p-STAT3 expression. Inhibition of JAK2/STAT3 signaling with AG490 markedly decreased MnSOD expression, increased ROS production, and aggravated myocardial injury. AG490 plus GSI exerted no additional effects. These results demonstrate that Notch signaling protects against burn-induced myocardial injury through JAK2/STAT3 signaling, which activates the expression of MnSOD and leads to decreased ROS levels

Application of the steady-state principle of constant-head well permeameter to indirect subsurface drip irrigation

Weixia, Z., Huanjie, C., Zhenhua, Z. and Zhijie, S 2009. Application of the steady-state principle of constant-head well permeameter to indirect subsurface drip irrigation. Can. J. Soil Sci. 89: 671-676. Indirect subsurface drip irrigation (ISDI) is a method of increasing the irrigation water use efficiency of drip irrigation without the need to bury irrigation tubes and wet the soil surface. A major problem of ISDI is the mismatch between emitter discharge rate and water-conducting device dimension, which will result in over-filling of application water. In this paper, we propose to use the steady-state principle of Coll stant-head well permeameter (CHWP) to quantify the relationship between emitter discharge rate and water-conducting device dimension For ISDI. CHWP tests and ISDI tests were carried out in a 300 in 2 winter wheat fallow to verify its feasibility. The steady-state characteristic of these two methods was also studied using long-term infiltration. Results indicate that the equilibration time (110 min) in the ISDI tests was greater than that in the CHWP tests (30 min). The steady ponded depth in ISDI had a smaller variation than the steady water discharge rate in the CHWP. When using the steady-state principle of CHWP to design ISDI systems, there was significant linear correlation between predicted and measured ponded depth values (R(2) = 0.8379). The soil field-saturated hydraulic conductivity calculated by these two tests was approximately equal. These results demonstrate that the steady-state principle of CHWP could be used to select appropriate irrigation systems for ISDI, and ISDI provides another technique to obtain the field-saturated hydraulic conductivity

Associations of serum and urinary magnesium with the pre-diabetes, diabetes and diabetic complications in the Chinese Northeast population.

The effect of magnesium (Mg) deficiency on the prevalence of diabetes and diabetic complications has received a great attention. The present study investigated the association of Mg level in the serum or urine of the patients, lived in the Northeast areas of China, with either pre-diabetes or diabetes with and without complications. From January 2010 to October 2011, patients with type 1 diabetes (T1D, n = 25), type 2 diabetes (T2D, n = 137), impaired fasting glucose (IFG, n = 12) or impaired glucose tolerance (IGT, n = 15), and age/gender matched control (n = 50) were enrolled in the First Hospital of Jilin University. In T2D group, there were 24, 34, and 50 patients with nephropathy, retinopathy or peripheral neuropathy. Serum Mg levels in the patients with IGT, IFG, T2D, and T1D were significantly lower than that of control. The urinary Mg levels were significantly increased only in T2D and T1D patients compared to control. There was no difference for these two changes among T2D with and without complications; In addition, there was a significantly positive correlation of serum Mg levels with serum Ca levels only in T2D patients, and also a significantly positive correlation of urinary Mg levels with urinary Ca levels in control, IGT patients, and T2D patients. Simvastatin treatment in T2D patients selectively reduced serum Ca levels and urinary Mg levels. These results suggest that the potential impact of Mg deficiency on metabolic syndrome, diabetes and diabetic complications needs to be received special attention

Associations between serum Mg or urine Mg level as a continuous variable and laboratory parameters.

<p>Data presentation and abbreviation's spell are same as the description for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056750#pone-0056750-t001" target="_blank">Table 1</a>.</p>*<p>, <i>P</i><0.05 for the association.</p

Baseline characteristics stratified by Mg levels in T2D subjects.

<p>Data presentation and abbreviation's spell are same as the description for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056750#pone-0056750-t001" target="_blank">Table 1</a>.</p>*<p>, <i>P</i><0.05 vs High-Mg group.</p

Correlation between Mg with Ca in T2D patients.

<p>Correlations between serum Mg and serum Ca in T2D patients (r = 0.652, <i>P</i><0.000, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056750#pone-0056750-g003" target="_blank">Fig. 3A</a>). Correlations between urinary Mg and urinary Ca in T2D patients (r = 0.647, <i>P</i><0.000, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056750#pone-0056750-g003" target="_blank">Fig. 3B</a>).</p

Serum parameters in T2D patients treated with simvastatin.

<p>Data presentation and abbreviation's spell are same as the description for <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056750#pone-0056750-t001" target="_blank">Table 1</a>.</p>*<p>, <i>P</i><0.05 vs pretreatment.</p

Magnolia Extract (BL153) Ameliorates Kidney Damage in a High Fat Diet-Induced Obesity Mouse Model

Accumulating evidence demonstrated that obesity is a risk factor for renal structural and functional changes, leading to the end-stage renal disease which imposes a heavy economic burden on the community. However, no effective therapeutic method for obesity-associated kidney disease is available. In the present study, we explored the therapeutic potential of a magnolia extract (BL153) for treating obesity-associated kidney damage in a high fat diet- (HFD-) induced mouse model. The results showed that inflammation markers (tumor necrosis factor-α and plasminogen activator inhibitor-1) and oxidative stress markers (3-nitrotyrosine and 4-hydroxy-2-nonenal) were all significantly increased in the kidney of HFD-fed mice compared to mice fed with a low fat diet (LFD). Additionally, proteinuria and renal structure changes in HFD-fed mice were much more severe than that in LFD-fed mice. However, all these alterations were attenuated by BL153 treatment, accompanied by upregulation of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) and hexokinase II (HK II) expression in the kidney. The present study indicates that BL153 administration may be a novel approach for renoprotection in obese individuals by antiinflammation and anti-oxidative stress most likely via upregulation of PGC-1α and HK II signal in the kidney