SciCombinator

Discover the most talked about and latest scientific content & concepts.

Journal: Biological & pharmaceutical bulletin

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Epithelial sodium channel (ENaC) is an amiloride-sensitive sodium ion channel that is expressed in epithelial tissues. ENaC overexpression and/or hyperactivation in airway epithelial cells cause sodium over-absorption and dysregulated ciliary movement for mucus clearance; however, the agents that suppress constitutive airway ENaC activation are yet to be clinically available. Here, we focused on macrolides, which are widely used antibiotics that have many potential immunomodulatory effects. We examined whether macrolides could modulate constitutive ENaC activity and downstream events that typify cystic fibrosis (CF) and chronic obstructive pulmonary diseases (COPD) in in vitro and in vivo models of ENaC overexpression. Treatment of ENaC-overexpressing human bronchial epithelial cells (β/γENaC-16HBE14o- cells) with three macrolides (erythromycin, clarithromycin, azithromycin) confirmed dose-dependent suppression of ENaC function. For in vivo studies, mice harboring airway specific βENaC overexpression (C57BL/6J-βENaC-Tg mice) were treated orally with azithromycin, a well-established antimicrobial agent that has been widely prescribed. Azithromycin treatment modulated pulmonary mechanics, emphysematous phenotype and pulmonary dysfunction. Notably, a lower dose (3 mg kg-1) of azithromycin significantly increased forced expiratory volume in 0.1 second (FEV0.1), an inverse indicator of bronchoconstriction. Although not statistically significant, improvement of pulmonary obstructive parameters such as emphysema and lung dysfunction (FEV0.1%) was observed. Our results demonstrate that macrolides directly attenuate constitutive ENaC function in vitro and may be promising for the treatment of obstructive lung diseases with defective mucociliary clearance, possibly by targeting ENaC hyperactivation.

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The diagnosis of chronic fatigue syndrome (CFS) is mainly symptom-based, and the etiology is still unclear. Here, we evaluated the pathological changes in the brain of a mouse model of CFS and studied the effects of Kampo medicine. A mouse model of CFS was established through six repeated injections of Brucella abortus (BA) every two weeks for a period of 12 weeks. Neuroinflammation was measured by estimating interleukin (IL)-1β, IL-6, and interferon-gamma (IFN-γ), and oxidative stress by nitrotyrosine (3-NT) and 4-hydroxynonenal (4-HNE) 6 weeks after the last injection. Hippocampal neurogenesis was evaluated through Ki-67, doublecortin (DCX), and 5-bromodeoxyuridine (BrdU) assays. The effects of Kampo medicines (Hochuekkito (TJ-41) and Hachimijiogan (TJ-7)) on neuroinflammation during CFS were studied. The wheel-running activity of mice was decreased by about 50% compared to baseline at 6 weeks after the last BA injection. The levels of IL-1β, IL-6, 3-NT, and 4-HNE were increased in both the cortex and the hippocampus of CFS mice at 6 weeks after the last BA injection. Hippocampal neurogenesis was unchanged in CFS mice. Treatment with TJ-41 and TJ-7 reduced the expressions of IL-1β, IL-6, and IFN-γ in the hippocampus but not in the cortex. The results of the present study indicate that neuroinflammation and oxidative stress play important roles in the pathogenesis of CFS. The data further suggest that treatment with TJ-41 and TJ-7 could help reduce the inflammation associated with CFS in the hippocampus, but failed to improve the symptoms in CFS mice.

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The discovery of the chimeric tyrosine kinase breakpoint cluster region kinase-Abelson kinase (BCR-ABL)-targeted drug imatinib conceptually changed the treatment of chronic myelogenous leukemia (CML). However, some CML patients show drug resistance to imatinib. To address this issue, some artificial heterocyclic compounds have been identified as BCR-ABL inhibitors. Here we examined whether plant-derived pentacyclic triterpenoid gypsogenin and/or their derivatives show inhibitory activity against BCR-ABL. Among the three derivatives, benzyl 3-hydroxy-23-oxoolean-12-en-28-oate (1c) was found to be the most effective anticancer agent on the CML cell line K562, with an IC50 value of 9.3 µM. In contrast, the IC50 against normal peripheral blood mononuclear cells was 276.0 µM, showing better selectivity than imatinib. Compound 1c had in vitro inhibitory activity against Abelson kinase 1 (ABL1) (IC50=8.7 μM), the kinase component of BCR-ABL. In addition, compound 1c showed a different inhibitory profile against eight kinases compared with imatinib. The interaction between ATP binding site of ABL and 1c was examined by molecular docking study, and the binding mode was different from imatinib and newer generation inhibitors. Furthermore, 1c suppresses signaling downstream of BCR-ABL. This study suggests the possibility that plant extracts may be a source for CML treatment and offer a strategy to overcome drug resistance to known BCR-ABL inhibitors.

Concepts: Signal transduction, Adenosine triphosphate, Protein kinase, Leukemia, Chronic myelogenous leukemia, Imatinib, Philadelphia chromosome, Abl gene

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Alzheimer’s disease (AD) is a most serious age-related neurodegenerative disorder accompanied with significant memory impairments in this world. Recently, microRNAs have been reported to be invlolved in the pathophysiology of AD. Previous studies have shown that miR-206 is implicated in the pathogenesis of AD via suppressing the expression of BDNF in the brain. Here, we examined the miR-206-3p and miR-206-5p expression in the hippocampus and cortex of APP/PS1 transgenic mice treated with donepezil, a drug approved for treating AD in clinic. We found that the expression of miR-206-3p was significantly up-regulated in the hippocampus and cortex of APP/PS1 mice, while donepezil administration significantly reversed this dysfunction. In addition, enhancing the miR-206-3p level by the usage of AgomiR-206-3p significantly attenuated the anti-dementia effects of donepezil in APP/PS1 mice. Together, these results suggested that miR-206-3p is involved in the anti-dementia effects of donepezil, and could be a novel pharmacological target for treating AD.

Concepts: Alzheimer's disease, Brain, Neurology, Neurodegenerative disorders, Memory, Hippocampus, Semantic memory, Genetically modified organism

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Chronic Fatigue (CF) is a common reason for consulting a physician due to affecting quality of life, but only a few effective treatments are available. The aim of this study was to examine the effectiveness of subcutaneous injection of the human placental extract (HPE) on medically indescribable cases of CF and safety in a randomized, double-blind, placebo-controlled clinical trial. A total of seventy eight subjects with CF were randomly assigned to either a HPE group or a placebo group. Subjects in the HPE group were treated with HPE three times a week subcutaneously for 6 weeks, whereas those in the placebo group with normal saline. Then, the Fatigue Severity Scale (FSS), Visual Analog Scale (VAS) and Multidimensional Fatigue Inventory (MFI) were measured in both CF group and chronic fatigue syndrome (CFS) and idiopathic chronic fatigue (ICF) subgroup. The FSS, VAS and MFI score at baseline were not different between the HPE and placebo group in total subjects with CF. In CFS group, the FSS (p= 0.0242), VAS (p =0.0009) and MFI (p= 0.0159) scores measured at the end of the study period decreased more in the HPE group than in the placebo group when compared with those at the baseline. There were no significant differences between the HPE group and placebo group in the mean change from baseline in FSS, VAS, and MFI in subjects with ICF during the study period. The subcutaneous injection of HPE was effective in the improvement of CFS.

Concepts: Pharmacology, Medicine, Clinical trial, Effectiveness, Placebo, Group theory, Normal subgroup, Chronic fatigue syndrome

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For screening of skin-whitening ingredients that modulate inhibition of melanogenesis, tyrosinase promoter-based assay using a 3D spheroid culture technique is a beneficial tool to improve the accuracy of raw material screening in cosmetics through mimicking of the in vivo microenvironment. Although the advantages of high-throughput screening (HTS) are widely known, there has been little focus on specific cell-based promoter assays for HTS in identifying skin-whitening ingredients that inhibit accumulation of melanin. The aim of this study was therefore to develop a large-scale compatible assay through pTyr-EGFP, an enhanced green fluorescent protein (EGFP)-based tyrosinase-specific promoter, to seek potential melanogenesis inhibitors for cosmetic use. Herein, a stably transfected human melanoma cell line expressing EGFP under the control of a 2.2-kb fragment derived from the tyrosinase gene was generated. Spontaneous induction of the tyrosinase promoter by 3D spheroid culture resulted in increased expression of EGFP, providing a significant correlation with the tyrosinase mRNA level, and subsequent inhibition of tyrosinase activity. Importantly, the pTyr-EGFP system provided successful tracking of the changes in the live image and real-time monitoring. Thus tyrosinase promoter-based fluorescent assay using a 3D spheroid culture can be useful as a screening system for exploring the efficiency of anti-melanogenesis ingredients.

Concepts: Protein, Green fluorescent protein, Cell culture, Enzyme inhibitor, Inhibitor, Melanin, Melanocyte, Tyrosinase

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Regulating synaptic formation and transmission is critical for the physiology and pathology of psychiatric disorders. The adenosine A2A receptor subtype has attracted widespread attention as a key regulator of neuropsychiatric activity, neuroprotection and injury. In this study, we systematically investigated the regulatory effects of a novel A2A receptor agonist, PSB-0777, on the expression of synaptic proteins and AMPA receptors at the cellular level in a time- and dose-dependent manner. After 30 minutes of high-dose PSB-0777 stimulation, the expression of Syn-1, PSD95, and AMPA receptors and the number of synapses were rapidly and significantly increased in rat primary cortical neurons compared with the control. Sustained elevation was found in the low and medium-dose groups after 24 hours and 3 days of treatment. In contrast, after stimulation with PSB-0777 for 3 consecutive days, the expression of Syn-1 was decreased, and PSD95, AMPA receptors and the number of synapses were no longer increased in the high-dose group. Our study focuses on the detailed and systematic regulation of synaptic proteins and AMPA receptors by an A2A receptor agonist, PSB-0777, which may result in both beneficial and detrimental effects on neurotransmission and neuroprotection and may contribute to the pathophysiology of psychiatric disorders related to A2A receptors. These experimental data may contribute to understanding of the mechanisms for neuroprotective and therapeutic effect of A2A receptor agonists.

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We retrospectively obtained data of patient background and pretreatment characteristics from medical records and identified the predictive factors of febrile neutropenia (FN) in patients with non-small cell lung cancer (NSCLC) treated with docetaxel alone or in combination with the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab.Patients were eligible for inclusion in the study if they were 20 years or older, diagnosed with NSCLC, and received docetaxel monotherapy alone or in combination with bevacizumab at the Department of Respiratory Medicine, Kobe City Medical Center General Hospital, between July 1, 2011, and March 31, 2018.Eighty-one patients with recurrent or advanced NSCLC were included. Multivariate stepwise logistic regression analysis with backward selection revealed that lower baseline Eastern Cooperative Oncology Group performance status (ECOG-PS) scores of 1 and 2 (odds ratio [OR], 5.098; 95% confidence interval [CI], 1.045-24.879, p=0.021) and baseline platelet count below 18.8 x 104/µL (OR, 3.861; 95% CI, 1.211-12.311, p=0.022) were significant factors influencing the FN occurrence rate.Our results demonstrated that ECOG-PS 1-2 and lower baseline platelet count were significant risk factors of FN in patients with NSCLC receiving docetaxel-based chemotherapy. Moreover, the combination of anti-VEGF antibodies and docetaxel might be associated with increased FN frequency. Despite the limitations of this study including its retrospective design, single-center site, and small sample size, baseline ECOG-PS score and platelet count may be regarded as important indices to identify patients for prophylactic granulocyte-colony stimulating factor (G-CSF) treatment before docetaxel-based chemotherapy.

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Inappropriately reduced doses (IRDs) of direct oral anticoagulants (DOACs) are common in clinical practice. We performed a retrospective review using electronic medical records of St. Marianna University School of Medicine Hospital (a 1200-bed teaching hospital in Japan) to address the prevalence of IRDs and patient-related factors that result in IRDs. We also surveyed DOAC-treated patients who were hospitalized due to a stroke during the 5-year study period to analyze the association between stroke events and IRDs. We found that one in five patients who were newly prescribed a DOAC was treated with IRDs. Patients treated with edoxaban received the most IRDs (64%, 7/11), followed by those treated with dabigatran (50%, ½), apixaban (32%, 19/61), and rivaroxaban (27%, 12/44). Our analysis showed that the renal function (measured as serum creatinine and creatinine clearance values) and age are possible factors influencing dose reduction. The HAS-BLED score and antiplatelet use were not associated with IRD prescription. An analysis of the 5-year hospital records revealed 20 stroke cases despite ongoing treatments with DOACs, and IRDs were noted in three of these cases. In all three cases, the patients had been on an IRD of rivaroxaban. To prevent IRDs of DOACs, we suggest that a clinical protocol be incorporated into formularies to support the prescription process.

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Latifolin, a natural flavonoid found in Dalbergia odorifera T. Chen, has been reported to exhibit anti-inflammatory and anticarcinogenic activities in vitro. However, the anti-aging effects of latifolin are unknown. In this study, we selected a model in vitro system, hydrogen peroxide (H2O2)-induced senescence in human dermal fibroblasts (HDFs), to examine the protective effects of latifolin against senescence and the detailed molecular mechanisms involved. Latifolin reversed the senescence-like phenotypes of the oxidant-challenged model, including senescence-associated β-galactosidase (SA-β-gal) staining, cell proliferation, and the expression of senescence-related proteins, such as caveolin-1, ac-p53, p21Cip1/WAF1, p16Ink4α, pRb, and cyclinD1. We also found that latifolin induced the expression of silent information regulator 1 (SIRT1) in a concentration- and time-dependent manner, and the anti-senescence effect of latifolin was abrogated by SIRT1 inhibition. Latifolin also suppressed the activation of Akt and S6K1 and attenuated the increase in SA-β-gal activity after H2O2 exposure. Our results indicate that latifolin exerts protective effects against senescence in HDFs and that induction of SIRT1 and inhibition of the mTOR pathway are key mediators of its anti-aging effects.