8373412
Expression of uncoupling protein 3 is upregulated in skeletal muscle during sepsis.
Uncoupling protein 3 (UCP3) is a member of the mitochondrial transporter superfamily that is expressed primarily in skeletal muscle. UCP3 is upregulated in various conditions characterized by skeletal muscle atrophy, including hyperthyroidism, fasting, denervation, diabetes, cancer, lipopolysaccharide (LPS), and treatment with glucocorticoids (GCs). The influence of sepsis, another condition characterized by muscle cachexia, on UCP3 expression and activity is not known. We examined UCP3 gene and protein expression in skeletal muscles from rats after cecal ligation and puncture and from sham-operated control rats. Sepsis resulted in a two- to threefold increase in both mRNA and protein levels of UCP3 in skeletal muscle. Treatment of rats with the glucocorticoid receptor antagonist RU-38486 prevented the sepsis-induced increase in gene and protein expression of UCP3. The UCP3 mRNA and protein levels were increased 2.4- to 3.6-fold when incubated muscles from normal rats were treated with dexamethasone (DEX) and/or free fatty acids (FFA) ex vivo. In addition, UCP3 mRNA and protein levels were significantly increased in normal rat muscles in vivo with treatment of either DEX or FFA. The results suggest that sepsis upregulates the gene and protein expression of UCP3 in skeletal muscle, which may at least in part be mediated by GCs and FFA.
25793180
Sepsis induces the transcription of the glucocorticoid receptor in skeletal muscle cells.
Evidence from a recent study indicates that glucocorticoids (GCs) mediate skeletal muscle proteolysis during sepsis via the GC receptor (GR) pathway. Attempts to identify the mechanisms regulating GR gene expression in skeletal muscle during sepsis have been hampered by the lack of an appropriate in vitro model system that can mimic in vivo septic conditions. In the present study, we report that GR gene transcription in L6 myocytes in vitro is up-regulated by treatment with sera from septic rats in a manner similar to that measured in septic rats in vivo. Sera from septic rats were collected from animals in which sepsis was induced by caecal ligation and puncture and from control rats that were sham-operated. Finally, by treating L6 myotubes with the GR antagonist RU 38486, thereby preventing sepsis-induced GR transcription, we confirmed that the possible septic effect on the GR was due to increased GCs. L6 myocytes treated with sera from septic rats might therefore be useful as an experimental model for identifying the molecular mechanisms by which the GR regulates muscle cachexia during sepsis. Furthermore, RU 38486 inhibited the sepsis-induced increase in total and myofibrillar energy-dependent protein breakdown rates in incubated extensor digitorum longus muscles from septic and sham-operated rats, as measured by release of tyrosine and 3-methylhistidine respectively. Our results demonstrate for the first time that sepsis induces GR transcription in skeletal muscle, and supports the hypothesis that the GC-induced proteolysis under sepsis is partially a consequence of GR activation.
36944421
Effect of burn injury on glucocorticoid receptor binding activity in rat muscle.
Burn injury is associated with increased muscle proteolysis and up-regulated gene expression in the proteolytic pathway. Glucocorticoids (GCs) are the most important mediator of burn injury induced muscle cachexia. However, the understanding of the mechanisms of GCs action in response to burn injury remains elusive. It is well known that GC acts by binding its own receptor. Therefore, in the present study, we examined the influence of burn injury on the hormone binding activity of the glucocorticoid receptor (GR) in skeletal muscle. Burn injury resulted in increased hormone binding activity in extensor digitorum longus (EDL) and soleus muscles. Scatchard plots revealed that the increased GR hormone binding activity reflected increased numbers of hormone binding sites, whereas receptor affinity for GCs was unchanged. Western blot analysis showed that dissociation of GR/heat shock protein 90 heterocomplex or increase in GR protein may account for the effect of burn injury. The GR antagonist RU 38486 blocked the burn injury-induced increase in GR hormone binding activity, implicating a positive regulatory effect of GCs on GR binding activity under the present experimental conditions.
241983
Interruption of nuclear localization of ATBF1 during the histopathologic progression of head and neck squamous cell carcinoma.
BACKGROUND
The AT-motif binding factor 1 (ATBF1) gene is frequently altered at the genetic level in several types of cancer, but its protein expression and subcellular localization have not been well studied in human cancers, including head and neck squamous cell carcinomas (HNSCCs).


METHODS
ATBF1 expression and localization were examined in 5 cell lines and 197 clinical specimens of HNSCC, and correlated with pathologic and clinical characteristics.


RESULTS
ATBF1 was predominantly localized in the nucleus of hyperplastic squamous epithelium. Whereas nuclear ATBF1 dramatically decreased in invasive tumors (p = .0012), cytoplasmic ATBF1 levels progressively increased from dysplasia to invasive tumors (p < .0001), and the increase correlated with poor survival. Reduced nuclear ATBF1 level was also detected in HNSCC cell lines.


CONCLUSIONS
Nuclear localization of ATBF1 is frequently interrupted in HNSCC, and the interruption is significantly associated with the progression of HNSCC. The cytoplasmic ATBF1 level could be useful for predicting patient survival.
28366299
Design of fluorescent self-assembled multilayers and interfacial sensing for organophosphorus pesticides.
This paper details the fabrication of indole (ID) self-assembled multilayers (SAMs) and fluorescence interfacial sensing for organophosphorus (OP) pesticides. Quartz/APES/AuNP/L-Cys/ID film was constructed on L-cysteine modified Quartz/APES/AuNP surface via electrostatic attraction between ID and L-cysteine. Cyclic voltammetry indicates that ID is immobilized successfully on the gold surface. Fluorescence of the Quartz/APES/AuNP/L-Cys/ID film shows sensitive response toward OPs. The fluorescent sensing conditions of the SAMs are optimized that allow linear fluorescence response for methylparathion and monocrotophos over 5.97 x 10(-7) to 3.51 x 10(-6)gL(-1) and 3.98 x 10(-6) to 3.47 x 10(-5)gL(-1), with detection limit of 6.1 x 10(-8)gL(-1) and 3.28 x 10(-6)gL(-1), respectively. Compared to bulk phase detection, interfacial fluorescence sensing based on the SAMs technology shows higher sensitivity by at least 2 order of magnitude.
35324869
Palladium-catalyzed C-N cross coupling of sulfinamides and aryl halides.
The palladium-catalyzed C-N cross coupling of sulfinamides and aryl halides is reported. In the presence of Pd(2)(dba)(3), tBuXPhos, NaOH, and a small amount of water, the C-N cross coupling of chiral tert-butanesulfinamide and aryl halides was accomplished to give N-aryl tert-butanesulfinamide without racemization, and the coupling of racemic p-toluenesulfinamide smoothly afforded N-aryl p-toluenesulfinamides. 2-Bromopyridine was also suitable for the coupling. Addition of a small amount of water to the catalytic system was of importance to obtain high yields.
9295570
Antisense HIF-1α prevents acquired tumor resistance to angiostatin gene therapy
Angiostatin is a naturally occurring inhibitor of angiogenesis that is being developed as a drug to fight cancer. In this study we reveal that EL-4 tumors established in mice rapidly develop resistance to angiostatin gene therapy by upregulating hypoxia-inducible pathways. Angiostatin initially delayed tumor growth for 6 days by reducing blood vessel density. However, tumors quickly responded by upregulating the production of hypoxia-inducible factor-1α (HIF-1α) and its effector vascular endothelial growth factor (VEGF) in response to increasing tumor hypoxia, leading to restored angiogenesis and rapid tumor growth. Theoretically, blockade of HIF-1 should prevent resistance to anti-angiogenic therapy by preventing a tumor from responding to induced hypoxia. Antisense HIF-1α inhibited the expression of HIF-1α and of the HIF-1 effectors VEGF, glucose transporter-1 and lactate dehydrogenase. As a monotherapy, it was effective in eradicating small 0.1 cm diameter tumors, but only delayed the growth of large 0.4 cm diameter tumors. In contrast, timed injection of a combination of angiostatin and antisense HIF-1α plasmids completely eradicated large EL-4 tumors within 2 weeks, and prevented upregulation of hypoxia-inducible pathways induced by angiostatin. The data indicate that blocking hypoxia-inducible pathways by antisense HIF-1α can circumvent hypoxia-induced drug resistance and thereby augment the efficacy of anti-angiogenic therapies.
902426
The effect of telomerase activity on vascular smooth muscle cell proliferation in type 2 diabetes in vivo and in vitro.
Serious complications as a result of type 2 diabetes mellitus (T2DM) are becoming a major health concern. In the present study, it was hypothesized that telomerase activity is upregulated in vascular smooth muscle cells (VSMCs) during proliferation in T2DM and that the application of telomerase inhibitors impedes the proliferation of VSMCs in vitro. Male Wistar rats were randomly allocated into the normal control (NC) or diabetic (DM) group. Diabetes was induced by high‑fat feeding and a low dose of streptozotocin (STZ; 30 mg/kg). Primary VSMC cultures were exposed to normal (5.5 mM) or high (25 mM) glucose and insulin (100 nM) in the presence and absence of various concentrations of antisense oligoribonucleotides (ASODNs) for varying lengths of time. Telomerase activity and the proliferation of VSMCs were measured. Results showed that there was a significant increase in the levels of fasting glucose, insulin, triglycerides (TG) and free fatty acids (FFAs) in the diabetic group. Telomerase activity and the proliferation of VSMCs were significantly higher in the diabetic group in vivo and in the high glucose and insulin (HGI)-treated group in vitro (P<0.01). ASODNs significantly inhibited the proliferation of VSMCs in a concentration- and time‑dependent manner (P<0.01). In conclusion, hyperglycemia and hyperinsulinemia stimulate telomerase activity and the proliferation of VSMCs, while the inhibition of telomerase activity reduces the proliferation of VSMCs, indicating that telomerase may be involved in the pathological process of diabetic vascular disease.