Effect of Cblin and celastrol on muscle atrophy

Two novel reagents, N-myristoylated Cbl-b inhibitory peptide (C14-Cblin) and celastrol, a quinone methide triterpene, are reported to be effective in preventing myotube atrophy. The combined effects of C14-Cblin and celastrol on rat L6 myotubes atrophy induced by 3D-clinorotation, a simulated microgravity model, was investigated in the present study. We first examined their effects on expression in atrogenes. Increase in MAFbx1/atrogin-1 and MuRF-1 by 3D-clinorotation was significantly suppressed by treatment with C14-Cblin or celastrol, but there was no additive effect of simultaneous treatment. However, celastrol significantly suppressed the upregulation of Cbl-b and HSP70 by 3D-clinorotation. Whereas 3D-clinorotation decreased the protein level of IRS-1 in L6 myotubes, C14-Cblin and celastrol inhibited the degradation of IRS-1. C14-Cblin and celastrol promoted the phosphorylation of FOXO3a even in microgravity condition. Simultaneous administration of C14-Cblin and celastrol had shown little additive effect in reversing the impairment of IGF-1 signaling by 3D-clinorotation. While 3D-clinorotation-induced marked oxidative stress in L6 myotubes, celastrol suppressed 3D-clinorotation-induced ROS production. Finally, the C14-Cblin and celastrol-treated groups were inhibited decrease in L6 myotube diameter and increased the protein content of slow-twitch MyHC cultured under 3D-clinorotation. The simultaneous treatment of C14-Cblin and celastrol additively prevented 3D-clinorotation-induced myotube atrophy than single treatment

Increase of nitrosative stress in patients with eosinophilic pneumonia

<p>Abstract</p> <p>Background</p> <p>Exhaled nitric oxide (NO) production is increased in asthma and reflects the degree of airway inflammation. The alveolar NO concentration (Calv) in interstitial pneumonia is reported to be increased. However, it remains unknown whether NO production is increased and nitrosative stress occurs in eosinophilic pneumonia (EP). We hypothesized that nitrosative stress markers including Calv, inducible type of NO synthase (iNOS), and 3-nitrotyrosine (3-NT), are upregulated in EP.</p> <p>Methods</p> <p>Exhaled NO including fractional exhaled NO (FE_NO) and Calv was measured in ten healthy subjects, 13 patients with idiopathic pulmonary fibrosis (IPF), and 13 patients with EP. iNOS expression and 3-NT formation were assessed by immunocytochemistory in BALf cells. The exhaled NO, lung function, and systemic inflammatory markers of the EP patients were investigated after corticosteroid treatment for 4 weeks.</p> <p>Results</p> <p>The Calv levels in the EP group (14.4 ± 2.0 ppb) were significantly higher than those in the healthy subjects (5.1 ± 0.6 ppb, p < 0.01) and the IPF groups (6.3 ± 0.6 ppb, p < 0.01) as well as the FE_NOand the corrected Calv levels (all p < 0.01). More iNOS and 3-NT positive cells were observed in the EP group compared to the healthy subject and IPF patient. The Calv levels had significant positive correlations with both iNOS (r = 0.858, p < 0.05) and 3-NT positive cells (r = 0.924, p < 0.01). Corticosteroid treatment significantly reduced both the FE_NO(p < 0.05) and the Calv levels (p < 0.01). The magnitude of reduction in the Calv levels had a significant positive correlation with the peripheral blood eosinophil counts (r = 0.802, p < 0.05).</p> <p>Conclusions</p> <p>These results suggested that excessive nitrosative stress occurred in EP and that Calv could be a marker of the disease activity.</p

サービングサイズ オ モチイタ カンイ ショクモツ セッシュリョウ チョウサホウ ノ カイハツ

近年,生活習慣病の深刻化に伴い,管理栄養士に高度な専門知識や技能が求められるようになった。対象者の食行動の変容を目的とした栄養教育の過程で,栄養状態や食習慣の十分な把握は重要であり,実際に個人または集団レベルでの食物および栄養摂取量評価のために食事調査が行われている。その方法は多種類あるが,我々は個人および集団を対象とし,簡便かつ調査者および被調査者の負担が軽く,より正確な摂取状況を把握する方法としてサービングサイズを用いた簡易食物摂取量調査法を開発するために,20歳代女子大生に見合った簡易記録法(以下,簡易法)I,IIを作成し,段階的調査を行った。簡易法の摂取栄養量の算出のため,食品群別荷重平均成分表(以下,荷重平均成分表)を作成し,24時間秤量法(以下,秤量法)との整合性をはかり,精度を高める検討をした。秤量法と簡易法の一回目の検討の結果,食品群では調味料類を除いて有意な差は認められなかったが,食品摂取量の間に相違がみられた。栄養素では,ナトリウム(以下,Na)を除いて有意な差は認められなかった。両調査法間の相関関係は,全ての食品群で有意な正の相関がみられた。栄養素では,レチノール当量を除いて有意な正の相関が認められた。しかし,簡易法の摂取量と秤量法のそれとの間の近似をはかるために,1日の目標量を訂正し,両調査法の二度目の検討を行った。調査IIの結果,食品群では嗜好飲料類を除いて有意な差は認めらなかった。両調査法による食品摂取量は,目標量に対する充足率80&acd;120%を示し,近似値が認められた。栄養素では,鉄(以下,Fe),レチノール当量,ビタミンC(以下,VC)を除いて有意な差は認められなかった。両調査法間の相関関係は,嗜好飲料類を除く全ての食品群で有意であった。また,全ての栄養素で有意な正の相関が認められた

More than Just an Immunosuppressant: The Emerging Role of FTY720 as a Novel Inducer of ROS and Apoptosis

Fingolimod hydrochloride (FTY720) is a first-in-class of sphingosine-1-phosphate (S1P) receptor modulator approved to treat multiple sclerosis by its phosphorylated form (FTY720-P). Recently, a novel role of FTY720 as a potential anticancer drug has emerged. One of the anticancer mechanisms of FTY720 involves the induction of reactive oxygen species (ROS) and subsequent apoptosis, which is largely independent of its property as an S1P modulator. ROS have been considered as a double-edged sword in tumor initiation/progression. Intriguingly, prooxidant therapies have attracted much attention due to its efficacy in cancer treatment. These strategies include diverse chemotherapeutic agents and molecular targeted drugs such as sulfasalazine which inhibits the CD44v-xCT (cystine transporter) axis. In this review, we introduce our recent discoveries using a chemical genomics approach to uncover a signaling network relevant to FTY720-mediated ROS signaling and apoptosis, thereby proposing new potential targets for combination therapy as a means to enhance the antitumor efficacy of FTY720 as a ROS generator. We extend our knowledge by summarizing various measures targeting the vulnerability of cancer cells’ defense mechanisms against oxidative stress. Future directions that may lead to the best use of FTY720 and ROS-targeted strategies as a promising cancer treatment are also discussed

A genome-wide screen for FTY720-sensitive mutants reveals genes required for ROS homeostasis

Fingolimod hydrochloride (FTY720), a sphingosine-1-phosphate (S1P) analogue, is an approved immune modulator for the treatment of multiple sclerosis (MS). Notably, in addition to its well-known mode of action as an S1P modulator, accumulating evidence suggests that FTY720 induces apoptosis in various cancer cells via reactive oxygen species (ROS) generation. Although the involvement of multiple signaling molecules, such as JNK (Jun N-terminal kinase), Akt (alpha serine/threonine-protein kinase) and Sphk has been reported, the exact mechanisms how FTY720 induces cell growth inhibition and the functional relationship between FTY720 and these signaling pathways remain elusive. Our previous reports using the fission yeast Schizosaccharomyces pombe as a model system to elucidate FTY720-mediated signaling pathways revealed that FTY720 induces an increase in intracellular Ca2+ concentrations and ROS generation, which resulted in the activation of the transcriptional responses downstream of Ca2+/calcineurin signaling and stress-activated MAPK signaling, respectively. Here, we performed a genome-wide screening for genes whose deletion induces FTY720-sensitive growth in S. pombe and identified 49 genes. These gene products are related to the biological processes involved in metabolic processes, transport, transcription, translation, chromatin organization, cytoskeleton organization and intracellular signal transduction. Notably, most of the FTY720-sensitive deletion cells exhibited NAC-remedial FTY720 sensitivities and dysregulated ROS homeostasis. Our results revealed a novel gene network involving ROS homeostasis and the possible mechanisms of the FTY720 toxicity

Chromosome passenger complex is required for the survival of cells with ring chromosomes in fission yeast

<div><p>Ring chromosomes are circular chromosomal abnormalities that have been reported in association with some genetic disorders and cancers. In <i>Schizosaccharomyces pombe</i>, lack of function of protection of telomere 1 (Pot1) or telomerase catalytic subunit (Trt1) results in survivors with circular chromosomes. Hitherto, it is poorly understood how cells with circular chromosomes survive and how circular chromosomes are maintained. Fission yeast Cut17/Bir1, Ark1, Pic1, and Nbl1 is a conserved chromosome passenger complex (CPC) functioning mainly throughout mitosis. Here, using a temperature-sensitive mutant of CPC subunits, we determined that CPC is synthetically lethal in combination with either Pot1 or Trt1. The <i>pot1Δ pic1-T269</i> double mutant, which has circular chromosomes, showed a high percentage of chromosome mis-segregation and DNA damage foci at 33°C. We furthermore found that neither Shugoshin Sgo2 nor heterochromatin protein Swi6, which contribute to the centromeric localization of CPC, were required for the survival in the absence of Pot1. Both the <i>pot1Δ sgo2Δ</i> and <i>pot1Δ swi6Δ</i> double mutants displayed a high percentage of DNA damage foci, but a low percentage of chromosome mis-segregation, suggesting the link between the high percentage of chromosome mis-segregation and the lethality of the <i>CPC pot1Δ</i> double mutant. Our results suggest that CPC is required for the survival of cells with circular chromosomes and sheds light on the possible roles of CPC in the maintenance of circular chromosomes.</p></div

Pic1 is required for the survival of <i>trt1Δ</i> cells having circular chromosomes.

<p>(A) <i>trt1Δ pic1-T269</i> cells were streaked on YEA+FUDR plates to select for cells that could grow after the loss of plasmid expressing <i>trt1</i>^<i>+</i> and <i>tk</i>^<i>+</i>. The plasmid was retained on EMM plates supplemented with leucine and uracil (EMM+LU). (B) <i>trt1Δ pic1-T269</i> double mutants lost telomeric DNA. The loss of telomeric DNA in <i>trt1Δ pic1-T269</i> double mutant survivors was analyzed by Southern hybridization at 25°C. (C) NotI-digested chromosomal DNA from <i>pic1-T269</i>, <i>trt1Δ</i> and <i>trt1Δ pic1-T269</i> cells were analyzed by PFGE at 25°C. (D) Lack of function of Pic1 results in loss of the viability of <i>trt1Δ</i> with circular chromosome. <i>trt1Δ pic1-T269</i> double mutant cells having circular chromosomes were streaked on YEA plates at 33°C to examine the ability of the cells to grow. <i>trt1Δ</i> with circular chromosomes and <i>pic1-T269</i> were used as controls.</p

Survival of the double mutants before and after loss of Pot1 plasmid.

<p>The <i>pot1Δ cut17-275</i>, <i>pot1Δ bir1-T1</i>, <i>pot1Δ ark1-T7</i>, <i>pot1Δ ark1-T8</i> and <i>pot1Δ pic1-T269</i> double mutants carrying plasmid-borne <i>pot1</i>^<i>+</i> and <i>tk</i>^<i>+</i> were streaked on selective and counter-selective media at the indicated temperatures. Pot1 plasmid was retained on EMM plates with adenine and uracil (EMM+AU). FUDR-containing plates were used as a counter selection to examine the ability of cells to grow after loss of the Pot1 plasmid.</p