Fbxw7β is an inducing mediator of dexamethasone-induced skeletal muscle atrophy in vivo with the axis of Fbxw7β-myogenin–atrogenes

Molecular Biology Reports - Muscle atrophy is induced by several pathways, e.g., it can be attributed to inherited cachectic symptoms, genetic disorders, sarcopenia, or chronic side effects of...     

Stable expression of a fungal laccase protein using transplastomic tobacco

Laccase catalyzes the oxidation of various phenolic compounds that can be used in a wide range of industrial applications such as waste detoxification and the textile industry. In the present study, we generated transplastomic tobacco plants to develop a reliable commercial source of laccase production. The stability of the laccase protein in the transgenic plants was increased by using the enhancer sequence from green fluorescent protein, resulting in three independent lines with high levels of laccase accumulation (up to 2?% of total protein); significant laccase activity, however, was not detected. Interestingly, the transplastomic lines showed slightly retarded vegetative growth, with a light green leaf color in comparison with the control, which may be attributable to copper deficiency induced by ligand chelation by abundantly produced laccase. These results suggest that the tobacco chloroplast is an efficient system for the mass production of laccase protein, but further studies are needed to obtain active enzyme.     

Statin Intensity and Clinical Outcome in Patients with Stable Coronary Artery Disease and Very Low LDL-Cholesterol

BackgroundAlthough intensive statin therapy is recommended for high risk patients, evidence of its benefit in patients with stable coronary artery disease (CAD) and very low low-density lipoprotein-cholesterol (LDL-C) has been very rare. In this study, we investigated whether higher statin intensity reduces cardiovascular risks in this population.MethodsIn this retrospective study, a total of 5234 patients with stable CAD were screened at three tertiary hospitals in Korea; 449 patients (mean age: 65 years, male: 69%) with LDL-C <80 mg/dL were finally analyzed. The statin intensities were classified according to the 2013 American College of Cardiology/American Heart Association guidelines. Patients who received statins equivalent to or weaker than atorvastatin 10 mg (group 1) were compared with those who took statins equivalent to or stronger than atorvastatin 20 mg (group 2). The impact of statin intensity on major adverse cardiac events (MACE) was evaluated during follow-up.ResultsGroup 1 and group 2 consisted of 181 patients (40.3%) and 268 patients (59.7%), respectively. The mean LDL-C level decreased to 52 and 57 mg/dL in group 1 and group 2, respectively, during follow-up. In a median follow-up of 4.5 years, patients of group 2 had a lower incidence of MACE (30 [16.6%] vs. 12 [4.5%], p <0.001), which were mostly related to a lower incidence of coronary revascularization. Cox proportional hazard analyses identified the statin intensity of group 2 (adjusted hazard ratio: 0.25, confidence interval: 0.11–0.55, p <0.001) and the baseline high-density lipoprotein-cholesterol level as independent determinants of MACE.ConclusionThis study provides evidence that higher intensity statins are beneficial for cardiovascular outcomes in patients with stable CAD and very low LDL-C. Statins equivalent to or stronger than atorvastatin 20 mg are more effective than lower intensity statins.     

CHIP regulates skeletal development and postnatal bone growth

C terminus of Hsc70-interacting protein (CHIP) is a chaperone-dependent and U-box containing E3 ubiquitin ligase. In previous studies, we found that CHIP regulates the stability of multiple tumor necrosis factor receptor-associated factor proteins in bone cells. In Chip global knockout (KO) mice, nuclear factor-κB signaling is activated, osteoclast formation is increased, osteoblast differentiation is inhibited, and bone mass is decreased in postnatal Chip KO mice. To determine the role of Chip in different cell types at different developmental stages, we created Chip^flox/flox mice. We then generated Chip conditional KO mice Chip^CMV and Chip^OsxER and demonstrated defects in skeletal development and postnatal bone growth in Chip conditional KO mice. Our findings indicate that Chip conditional KO mice could serve as a critical reagent for further investigations of functions of CHIP in bone cells and in other cell types.     

Effects of insulin and beta-adrenergic blockade on certain indicators of carbohydrate metabolism in the blood and tissues of rats during short-lasting hypothermia

Administration of insulin 1 i.u./100 g of body weight to hypothermic rats causes a fall of glucose and lactate levels in the serum and a rise in myocardial glycogen level in relation to the group of control rats kept at room temperature and to the group of rats subjected only to hypothermia. Beta-adrenergic blockade (propranolol 0.6-1 mg/kg) caused no changes in the levels of carbohydrate metabolites in the serum of hypothermic rats but raised the myocardial glycogen level by 42% in relation to the animals subjected only to hypothermia. Simultaneous administration of both these agents during hypothermia produces a fall of the serum levels of glucose and pyruvate with a rise in the level of lactate, and raises the glycogen level in the myocardium (by about 161%) and in the skeletal muscle (by 54%) in relation to the rats subjected to hypothermia alone. Insulin and/or propranolol fail to prevent glycogen reserve exhaustion in the liver of hypothermic rats which could be due to activation of non-blocked alpha-adrenergic receptors or to the action of yet another glycogenolytic agent, e.g. glucagon, during hypothermia.     

Interaction between obesity and genetic polymorphisms in the apolipoprotein CIII gene and lipoprotein lipase gene on the risk of hypertriglyceridemia in Chinese

To understand the effects of the interaction between genetic polymorphisms and obesity on the risk of hypertriglyceridemia (HTG), two polymorphisms, an SstI polymorphism on the apolipoprotein CIII gene and a HindIII polymorphism on the lipoprotein lipase gene, were analyzed in 339 Chinese subjects with (82 cases in the HTG group) or without HTG (257 cases in the control group). Our data revealed that the frequencies of obesity, the SstI minor allele (S2), and the HindIII major allele (H+) in the HTG group were significantly higher than in the control group. Subgroup analysis revealed that the association between these two polymorphisms and HTG occurred predominantly in nonobese subjects and in subjects with the less hypertriglyceridemic genotype of another polymorphism. Multivariate logistic regression analysis showed that all three risk factors (obesity, S2-containing chromosome, and H+ homozygosity) were associated with HTG, and an interaction was found between obesity and H+ homozygosity for the occurrence of HTG. The risk of HTG increased significantly with combinations of risk factors. Subjects can be divided into low or high risk groups for HTG using such combinations. These results provide evidence of interaction between obesity and the HindIII polymorphism of the lipoprotein lipase gene on the risk of HTG. Received: 27 November 1996 / Accepted: 28 March 1997     

High-level production of 3-hydroxypropionic acid from glycerol as a sole carbon source using metabolically engineered Escherichia coli

As climate change is an important environmental issue, the conventional petrochemical-based processes to produce valuable chemicals are being shifted toward eco-friendly biological-based processes. In this study, 3-hydroxypropionic acid (3-HP), an industrially important three carbon (C3) chemical, was overproduced by metabolically engineered Escherichia coli using glycerol as a sole carbon source. As the first step to construct a glycerol-dependent 3-HP biosynthetic pathway, the dhaB1234 and gdrAB genes from Klebsiella pneumoniae encoding glycerol dehydratase and glycerol reactivase, respectively, were introduced into E. coli to convert glycerol into 3-hydroxypropionaldehyde (3-HPA). In addition, the ydcW gene from K. pneumoniae encoding γ-aminobutyraldehyde dehydrogenase, among five aldehyde dehydrogenases examined, was selected to further convert 3-HPA to 3-HP. Increasing the expression level of the ydcW gene enhanced 3-HP production titer and reduced 1,3-propanediol production. To enhance 3-HP production, fed-batch fermentation conditions were optimized by controlling dissolved oxygen (DO) level and employing different feeding strategies including intermittent feeding, pH-stat feeding, and continuous feeding strategies. Fed-batch culture of the final engineered E. coli strain with DO control and continuous feeding strategy produced 76.2 g/L of 3-HP with the yield and productivity of 0.457 g/g glycerol and 1.89 g·L⁻¹·h⁻¹, respectively. To the best of our knowledge, this is the highest 3-HP productivity achieved by any microorganism reported to date.