CRY Drives Cyclic CK2-Mediated BMAL1 Phosphorylation to Control the Mammalian Circadian Clock.

Intracellular circadian clocks, composed of clock genes that act in transcription-translation feedback loops, drive global rhythmic expression of the mammalian transcriptome and allow an organism to anticipate to the momentum of the day. Using a novel clock-perturbing peptide, we established a pivotal role for casein kinase (CK)-2-mediated circadian BMAL1-Ser90 phosphorylation (BMAL1-P) in regulating central and peripheral core clocks. Subsequent analysis of the underlying mechanism showed a novel role of CRY as a repressor for protein kinase. Co-immunoprecipitation experiments and real-time monitoring of protein-protein interactions revealed that CRY-mediated periodic binding of CK2ß to BMAL1 inhibits BMAL1-Ser90 phosphorylation by CK2α. The FAD binding domain of CRY1, two C-terminal BMAL1 domains, and particularly BMAL1-Lys537 acetylation/deacetylation by CLOCK/SIRT1, were shown to be critical for CRY-mediated BMAL1-CK2ß binding. Reciprocally, BMAL1-Ser90 phosphorylation is prerequisite for BMAL1-Lys537 acetylation. We propose a dual negative-feedback model in which a CRY-dependent CK2-driven posttranslational BMAL1-P-BMAL1 loop is an integral part of the core clock oscillator.

Effects of repeated tooth pulp stimulation on concentrations of plasma catecholamines, corticosterone, and glucose in rats.

In this study, we examined whether tooth pulp stimulation (TPS) affects the stress responses in anesthetized rats. As for stress response indices, we monitored changes in the concentrations of plasma catecholamines (CAs) (adrenaline, noradrenaline, and dopamine), corticosterone (CS), and glucose (Glu). We observed that repeated TPS attenuated plasma adrenaline, dopamine, CS, and Glu levels compared with those of sham-TPS. After administering naloxone, an opioid antagonist, repeated TPS reversed the decreases in plasma CAs, CS, and Glu. These findings showed that the effects of repeated TPS may be mediated by endogenous opioid administration. Our findings suggest that repeated TPS can induce stress-analgesia and that an endogenous descending pain modulation system exists.

ROS stress resets circadian clocks to coordinate pro-survival signals.

Dysfunction of circadian clocks exacerbates various diseases, in part likely due to impaired stress resistance. It is unclear how circadian clock system responds toward critical stresses, to evoke life-protective adaptation. We identified a reactive oxygen species (ROS), H2O2 -responsive circadian pathway in mammals. Near-lethal doses of ROS-induced critical oxidative stress (cOS) at the branch point of life and death resets circadian clocks, synergistically evoking protective responses for cell survival. The cOS-triggered clock resetting and pro-survival responses are mediated by transcription factor, central clock-regulatory BMAL1 and heat shock stress-responsive (HSR) HSF1. Casein kinase II (CK2) -mediated phosphorylation regulates dimerization and function of BMAL1 and HSF1 to control the cOS-evoked responses. The core cOS-responsive transcriptome includes CK2-regulated crosstalk between the circadian, HSR, NF-kappa-B-mediated anti-apoptotic, and Nrf2-mediated anti-oxidant pathways. This novel circadian-adaptive signaling system likely plays fundamental protective roles in various ROS-inducible disorders, diseases, and death.

Synchronization of circadian Per2 rhythms and HSF1-BMAL1:CLOCK interaction in mouse fibroblasts after short-term heat shock pulse.

Circadian rhythms are the general physiological processes of adaptation to daily environmental changes, such as the temperature cycle. A change in temperature is a resetting cue for mammalian circadian oscillators, which are possibly regulated by the heat shock (HS) pathway. The HS response (HSR) is a universal process that provides protection against stressful conditions, which promote protein-denaturation. Heat shock factor 1 (HSF1) is essential for HSR. In the study presented here, we investigated whether a short-term HS pulse can reset circadian rhythms. Circadian Per2 rhythm and HSF1-mediated gene expression were monitored by a real-time bioluminescence assay for mPer2 promoter-driven luciferase and HS element (HSE; HSF1-binding site)-driven luciferase activity, respectively. By an optimal duration HS pulse (43°C for approximately 30 minutes), circadian Per2 rhythm was observed in the whole mouse fibroblast culture, probably indicating the synchronization of the phases of each cell. This rhythm was preceded by an acute elevation in mPer2 and HSF1-mediated gene expression. Mutations in the two predicted HSE sites adjacent (one of them proximally) to the E-box in the mPer2 promoter dramatically abolished circadian mPer2 rhythm. Circadian Per2 gene/protein expression was not observed in HSF1-deficient cells. These findings demonstrate that HSF1 is essential to the synchronization of circadian rhythms by the HS pulse. Importantly, the interaction between HSF1 and BMAL1:CLOCK heterodimer, a central circadian transcription factor, was observed after the HS pulse. These findings reveal that even a short-term HS pulse can reset circadian rhythms and cause the HSF1-BMAL1:CLOCK interaction, suggesting the pivotal role of crosstalk between the mammalian circadian and HSR systems.

Theophylline attenuates hippocampal blood flow responses induced by tooth pulp stimulation in rats.

In this study, we performed tests to determine whether tooth pulp stimulation (TPS) increases hippocampal blood flow (HBF), and if so, to investigate whether the increase in HBF is mediated via the activation of adenosine receptors. We measured HBF in urethane-anesthetized rats using laser Doppler flowmetry (LDF) and examined the effect of theophylline, a nonselective adenosine receptor antagonist, on TPS-induced HBF responses. TPS increased HBF, and its response was significantly attenuated by the intraperitoneal administration of theophylline (20 mg/kg). These results suggest that the HBF response induced by TPS may be, at least in part, produced through adenosine receptors.

Mucinous adenocarcinoma of the temporal region initially diagnosed as temporomandibular disorders: a case report.

Adenocarcinoma occurring in the temporal region has not previously been reported. We present a case of mucinous adenocarcinoma of the temporal region. A 62-year-old female patient was diagnosed as having temporomandibular disorders because of severe trismus and joint pain. Although trismus progressively worsened, there were no abnormal findings on diagnostic imaging studies including magnetic resonance imaging (MRI) and bone scintigraphy. As swelling of the temporal region was observed, biopsy was performed. Histologic examination showed chronic inflammation of the striated muscle. Approximately 6 months later, follow-up MRI demonstrated an ill-defined mass lesion in the infratemporal region extending to the intracranium. Histologic diagnosis of the biopsy showed that this mass lesion was moderately differentiated mucinous adenocarcinoma.

Phase I/II trial of docetaxel and carboplatin as a first-line therapy in patients with stage IV non-small-cell lung cancer.

A phase I/II study was conducted to determine the maximum-tolerated dose, the safety and tolerability, and the clinical efficacy of carboplatin and docetaxel in combination in patients with stage IV non-small-cell lung cancer. Patients with measurable, previously untreated, good performance status, and stage IV non-small-cell lung cancer were eligible. Increasing doses of docetaxel were given in combination with a fixed dose of carboplatin except at level 5. Cycles were repeated every four weeks. Seventy-seven patients were registered. In phase I, 27 patients were entered at five different dose levels. A docetaxel dose of 60 mg/m(2) and carboplatin area under the concentration time curve 6 was recommended for phase II, and an additional 50 patients were entered at this level for a total of 56 patients. Grade 3/4 neutropenia was the most common adverse event and occurred in 70% of the patients. Two patients had febrile neutropenia. Fifty-six patients were assessable for response; 21 partial responses were observed for an overall response rate of 37.5%. The median time to tumor progression was 4.0 months (range, 1.0-21.0 months), and the median survival was 12.9 months (range, 0.4-51.3 months). The one-year survival rate was 46.4%. The combination of docetaxel 60 mg/m(2) and carboplatin area under the concentration time curve 6 is feasible and effective in patients with stage IV non-small-cell lung cancer.