Alteration of monoaminergic systems in the caudal medulla and its possible link to diurnal increase of apnea in a mouse model of Rett syndrome.

PURPOSE: Methyl-CpG binding protein 2 (MeCP2)-deficient (Mecp2-/y) mice exhibit apneas that resemble respiratory abnormalities observed in Rett syndrome (RTT) patients. The present study aimed to clarify whether Mecp2-/y mice show diurnal variations in apnea as seen in RTT and how the MeCP2 deficiency affects monoaminergic systems that control breathing. METHODS: In 7-week-old Mecp2-/y mice, 24 h variation of apnea and effects of milnacipran, a serotonin/noradrenaline reuptake inhibitor, on the apnea were evaluated. The number of vesicular monoamine transporter 2 (VMAT2)-immunoreactive puncta in the caudal medulla was counted. Further, the effects of valproate (VPA) on the expression of tyrosine hydroxylase (TH) mRNA in the ventrolateral medulla of mice were assessed by RT-qPCR. RESULTS: Apnea occurred more frequently during the light phase under a 12:12 h light/dark environment in Mecp2-/y mice and milnacipran reduced apnea during the light phase but not during the dark phase. The number of VMAT2-immunoreactive puncta was reduced in Mecp2-/y mice. VPA treatment significantly increased TH mRNA expression in Mecp2-/y mice. CONCLUSION: Alteration of monoaminergic systems in the caudal medulla of Mecp2-/y mice is potentially relevant to the light-sensitive diurnal increase of apnea, and an improvement in monoaminergic neurotransmission can ameliorate the diurnal increase of apnea in Mecp2-/y mice.

Artepillin C overcomes apalutamide resistance through blocking androgen signaling in prostate cancer cells.

Prostate cancer has a relatively good prognosis, but most cases develop resistance to hormone therapy, leading to castration-resistant prostate cancer (CRPC). Androgen receptor (AR) antagonists and a cytochrome P450 17A1 inhibitor have been used to treat CRPC, but cancer cells readily develop resistance to these drugs. In this study, to improve the therapy of CRPC, we searched for natural compounds which block androgen signaling. Among cinnamic acid derivatives contained in Brazilian green propolis, artepillin C (ArtC) suppressed expressions of androgen-induced prostate-specific antigen and transmembrane protease serine 2 in a dose-dependent manner. Reporter assays revealed that ArtC displayed AR antagonist activity, albeit weaker than an AR antagonist flutamide. In general, aberrant activation of the androgen signaling is involved in the resistance of prostate cancer cells to hormone therapy. Recently, apalutamide, a novel AR antagonist, has been in clinical use, but its drug-resistant cases have been already reported. To search for compounds which overcome the resistance to apalutamide, we established apalutamide-resistant prostate cancer 22Rv1 cells (22Rv1/APA). The 22Rv1/APA cells showed higher AR expression and androgen sensitivity than parental 22Rv1 cells. ArtC inhibited androgen-induced proliferation of 22Rv1/APA cells by suppressing the enhanced androgen signaling through blocking the nuclear translocation of AR. In addition, ArtC potently sensitized the resistant cells to apalutamide by inducing apoptotic cell death due to mitochondrial dysfunction. These results suggest that the intake of Brazilian green propolis containing ArtC improves prostate cancer therapy.

A Multi-institutional Study to Diagnose the Risk of Lymph Node Metastasis Using a CRP Genetic Polymorphism Test Kit in pT1, cN0 Thoracic Esophageal Squamous Cell Carcinoma.

BACKGROUND/AIM: For patients with T1a muscularis mucosae (MM) esophageal squamous cell carcinoma (ESCC) with lymphovascular invasion (LVI) or T1b submucosal (SM) ESCC, endoscopic resection is non-curative, and adjuvant treatment entailing esophagectomy or definitive chemoradiotherapy is necessary. This is because about 30% of these cases have lymph node (LN) metastasis. The purpose of this study was to test the utility of a CRP genetic polymorphism test kit for determining the risk of LN metastasis with the aim of eliminating additional invasive adjuvant therapy. PATIENTS AND METHODS: This is a retrospective, multi-institutional, observational study. The CRP 1846C>T genetic polymorphisms were identified using a fully automated genotyping system. The primary end points were an 85% negative predictive value (NPV) for diagnosis of LN metastasis in pT1a (MM) and 80% NPV in pT1b (SM1) patients. RESULTS: A total of 742 ESCC (105 pMM, 166 pSM1 and 471 pSM2-3) patients who had received esophagectomy with 2- or 3-field LN dissection at 65 institutions were enrolled. According to this test, patients with the C/C and C/T genotypes were considered to be low risk. The NPVs using this test were 82.8% in pMM and 71.7% in pSM1 patients. CONCLUSION: CRP 1846C>T genetic polymorphism is not a useful diagnostic indicator for determining the risk of LN metastasis; however, the possibility that CRP gene polymorphisms are involved in the mechanism of lymph node metastasis in solid tumors still remains.

Targeting Nrf2-antioxidant signalling reverses acquired cabazitaxel resistance in prostate cancer cells.

Prostate cancer is known to have a relatively good prognosis, but long-term hormone therapy can lead to castration-resistant prostate cancer (CRPC). Cabazitaxel, a second-generation taxane, has been used for the CRPC treatment, but its tolerance is an urgent problem to be solved. In this study, to elucidate the acquisition mechanism of the cabazitaxel-resistance, we established cabazitaxel-resistant prostate cancer 22Rv1 (Cab-R) cells, which exhibited ∼sevenfold higher LD50 against cabazitaxel than the parental 22Rv1 cells. Cab-R cells showed marked increases in nuclear accumulation of NF-E2 related factor 2 (Nrf2) and expression of Nrf2-inducible antioxidant enzymes compared to 22Rv1 cells, suggesting that Nrf2 signalling is homeostatically activated in Cab-R cells. The cabazitaxel sensitivity of Cab-R cells was enhanced by silencing of Nrf2, and that of 22Rv1 cells was reduced by activation of Nrf2. Halofuginone (HF) has been recently identified as a potent Nrf2 synthetic inhibitor, and its treatment of Cab-R cells not only suppressed the Nrf2 signalling by decreasing both nuclear and cytosolic Nrf2 protein levels, but also significantly augmented the cabazitaxel sensitivity. Thus, inhibition of Nrf2 signalling may be effective in overcoming the cabazitaxel resistance in prostate cancer cells.

Is the Association between Green Tea Consumption and the Number of Remaining Teeth Affected by Social Networks?: A Cross-Sectional Study from the Japan Gerontological Evaluation Study Project.

Consumption of green tea without sugar, as well as social networks, are associated with a lower risk of tooth loss. There is a possibility of confounding both factors because tea is often drunk with friends. Therefore, the present study aimed to examine whether green tea consumption is beneficially associated with the number of remaining teeth, while considering social networks. This cross-sectional study was based on the Japan Gerontological Evaluation Study (JAGES) in 2016. Self-administered questionnaires containing questions about green tea consumption were mailed to 34,567 community-dwelling residents aged ≥ 65 years. We used the number of remaining teeth as a dependent variable, and green tea consumption and the number of friends met over the past month (social network size) as independent variables. Linear regression models with multiple imputation were used. A total of 24,147 people responded (response rate = 69.9%), and 22,278 valid data were included into our analysis. Participants' mean age was 74.2 years (standard deviation = 6.3), and 45.9% were men. Among the participants, 52.2% had ≥ 20 teeth, 34.2% drank 2-3 cups of green tea per day, and 32.6% met ≥ 10 people over the past month. After adjusting for all potential confounders, both higher green tea consumption and a larger social network size were associated with more remaining teeth (both p for trend < 0.001). The association of green tea was greater among those with smaller social networks (p for interaction < 0.05). The protective association of green tea was remarkable among people with smaller social networks.

Does public transportation reduce inequalities in access to dental care among older adults? Japan Gerontological Evaluation Study.

OBJECTIVES: Income inequalities in access to dental care have been reported worldwide. While geographical accessibility may affect inequalities, no study has examined whether the use of public transportation reduces income inequalities in access to dental care. Therefore, we examined whether the use of public transportation is associated with reduced income inequalities in access to dental care. METHODS: This cross-sectional study used data from the Japan Gerontological Evaluation Study conducted in 2016. Self-reported questionnaires were distributed to 34 567 community-dwelling independent older adults aged 65 years or over from 39 municipalities. The dependent variable was dental attendance for any treatment. The independent variables were daily public transportation use and household equivalent income. The covariates were age, years of education, marital status, self-rated health, number of teeth, car use, having bus stops or railway stations nearby for individual level and density of dental clinics for community level. After multiple imputation, a two-level linear regression analysis was performed and stratified by sex. RESULTS: The mean age of the 19 664 participants (response rate: 69.9%) was 73.8 years (standard deviation = 6.1). Among the participants with dental attendance for treatment in the past six months, daily public transportation users represented 45.5% of men and 56.1% of women. These users had higher levels of dental attendance for treatment (ß = .109, 95% confidence interval (CI) = 0.051-0.166 for men, ß = .094, 95% CI = 0.039-0.149 for women) than nondaily users. Household equivalent income was positively associated with higher dental attendance for treatment (ß = .046, 95% CI = 0.029-0.062 for men, ß = .029, 95% CI = 0.013-0.045 for women). Income inequalities in access to dental care were smaller among the daily public transportation users than in nondaily users, and a statistically significant interaction was observed only in men (P-value interactions = .025 for men, .188 for women). CONCLUSION: Income inequalities in access to dental care were smaller among older daily users of public transportation than in nondaily users. These results suggest that providing environment in which people can conveniently use public transportation is needed for reducing income inequalities in access to dental care, especially for men.

Early Postnatal Treatment with Valproate Induces Gad1 Promoter Remodeling in the Brain and Reduces Apnea Episodes in Mecp2-Null Mice.

The deletion of Mecp2, the gene encoding methyl-CpG-binding protein 2, causes severe breathing defects and developmental anomalies in mammals. In Mecp2-null mice, impaired GABAergic neurotransmission is demonstrated at the early stage of life. GABAergic dysfunction in neurons in the rostral ventrolateral medulla (RVLM) is considered as a primary cause of breathing abnormality in Mecp2-null mice, but its molecular mechanism is unclear. Here, we report that mRNA expression levels of Gad1, which encodes glutamate decarboxylase 67 (GAD67), in the RVLM of Mecp2-null (Mecp2-/y, B6.129P2(C)-Mecp2tm1.1Bird/J) mice is closely related to the methylation status of its promoter, and valproate (VPA) can upregulate transcription from Gad1 through epigenetic mechanisms. The administration of VPA (300 mg/kg/day) together with L-carnitine (30 mg/kg/day) from day 8 to day 14 after birth increased Gad1 mRNA expression in the RVLM and reduced apnea counts in Mecp2-/y mice on postnatal day 15. Cytosine methylation levels in the Gad1 promoter were higher in the RVLM of Mecp2-/y mice compared to wild-type mice born to C57BL/6J females, while VPA treatment decreased the methylation levels in Mecp2-/y mice. Chromatin immunoprecipitation assay revealed that the VPA treatment reduced the binding of methyl-CpG binding domain protein 1 (MBD1) to the Gad1 promoter in Mecp2-/y mice. These results suggest that VPA improves breathing of Mecp2-/y mice by reducing the Gad1 promoter methylation, which potentially leads to the enhancement of GABAergic neurotransmission in the RVLM.

Autophagy inhibition enhances anticancer efficacy of artepillin C, a cinnamic acid derivative in Brazilian green propolis.

Propolis, a resinous substance produced by honeybees, possesses various biological actions including anticancer activity towards tumor cells. Recently, the ethanol extract of Brazilian green propolis has been shown to induce autophagy, which is known to be induced in treatment of cancer cells with anticancer drugs, leading to cancer cell survival and decreased sensitivity to anticancer agents. In this study, we aimed to identify autophagy-inducing components of the propolis and elucidated the reciprocal relationship between anticancer cytotoxicity and protective autophagy in prostate cancer CWR22Rv1 cells. Among eight cinnamic acid derivatives [chlorogenic acid, p-coumaric acid, caffeic acid, 3,4-caffeoylquinic acid, artepillin C (ArtC), baccharin, drupanin and caffeic acid phenethyl ester] in propolis, only ArtC showed high autophagy-inducing activity accompanying LC3-II upregulation. ArtC was also induced apoptosis as revealed by DNA fragmentation and increases in cleaved caspase-3 and poly ADP-ribose polymerase. The apoptosis induced by ArtC was exacerbated by cotreatment with autophagy inhibitors (chloroquine, wortmannin and U0126). The cotreatment further induced necroptosis accompanying increased expression of receptor-interacting serine/threonine protein kinases 1 and 3. These data indicate that cytotoxicity of ArtC to the prostate cancer cells is dampened by induced autophagy, but is markedly augmented by inhibition of autophagy. Therefore, the combination of ArtC and autophagy inhibitors may be a novel complementary-alternative treatment for prostate cancer.