Donepezil, the most widely used drug for the treatment of Alzheimer's disease (AD), is an acetylcholinesterase (AChE) inhibitor and is thought to improve cognition by stimulating cholinergic neurotransmission. However, no correlation has yet been established between the inhibitory role of AChE inhibitors and their therapeutic effects when used in AD patients. The cleavage pathway of amyloid precursor protein (APP) includes amyloidgenic (β, γ-cleavage) and non-amyloidgenic (α-cleavage) pathways. The intracellular transportation of APP is important in determining these cleavage pathways. It has been suggested that sorting nexin (SNX) family proteins regulates the intracellular transport of APP, thereby enhancing α-cleavage. In this study, we examined the effects of donepezil on SNX33 expression changes and APP processing in primary cultures of fetal rat cortical neurons. While donepezil treatment increased the levels of SNX33 expression and soluble APPα (sAPPα) in culture media, no changes were observed regarding full-length APP expression in the cell lysate. Donepezil also reduced the release of amyloid β (Aβ) into culture media in a concentration- and time-dependent manner. This reduction was not affected by acetylcholine receptor antagonists. The membrane surface expression of APP was elevated by donepezil. Furthermore, SNX knockdown by antisense morpholino oligos prevented the effects of donepezil. These results indicated that donepezil increased APP expression at the surface of the plasma membrane by decreasing APP endocytosis through upregulation of SNX33, suggesting donepezil might stimulate the non-amyloidogenic pathway. This new mechanism of action for the currently used anti-AD drug may provide a valuable basis for future drug discovery.

Management of chemotherapy-induced adverse effects and the associated pharmaceutical interventions as well as supportive care evidence creation are the most important responsibilities of oncology pharmacists. We have evaluated the (1) efficacy of long-term and successive pharmaceutical care in outpatient chemotherapy and (2) nephroprotective effects of magnesium (Mg) against cisplatin-induced nephrotoxicity (CIN). The results revealed that the adoption rate of pharmaceutical proposals was 98%, and that approximately 70% of the proposals attenuated painful symptoms. Moreover, approximately 60% of pharmaceutical interventions were established after the third visit; in particular, approximately 20% were suggested after the tenth visit. These results have shown that long-term and successive pharmaceutical care by oncology pharmacists in outpatient chemotherapy contributes to a safe and less onerous chemotherapy implementation. CIN frequency and serum creatinine elevation were significantly attenuated by Mg premedication during the cisplatin, docetaxel, and fluorouracil regimen, without changes in adverse effects and response rate. Mg premedication has been suggested to exert a protective effect against CIN without influencing on adverse effects and anti-tumor efficacy. The nephroprotective effect of Mg against CIN was evaluated using Wistar rats. Cisplatin (2.5 mg/kg) was administered once or three times weekly with or without 40 mg/kg MgSO4. The results revealed that Mg regulates the expression of organic cation transporter 2, multidrug and toxin extrusion protein 1, and copper transporter 1, leading to reduced renal platinum accumulation, which results in CIN attenuation. In conclusion, evaluation of pharmaceutical care and supportive care by oncology pharmacists is necessary for advanced care of cancer patients.

Epigenetics is the study of heritable changes in gene expression that occur without alterations in the DNA sequence. Several studies have shown that environmental chemicals can alter epigenetic modifications, including histone modifications and DNA methylation. Environmental chemicals may show toxic effects via epigenetic mechanism-regulated changes in gene expression. Previously, we reported that zinc treatment rapidly decreased Lys(4)-trimethylated and Lys(9)-acetylated histone H3 in the metallothionein (MT) promoter, and also decreased total histone H3. The chromatin structure in the MT promoter may be locally disrupted by zinc-induced nucleosome removal. We also showed that chromium (VI) inhibited MT gene transcription by modifying the transcription potential of the co-activator p300. MT is a small cysteine-rich protein that is active in zinc homeostasis, cadmium detoxification, and protection against reactive oxygen species. Epigenetic changes might influence the cytoprotective function of the MT gene. In this review, I briefly summarize the results of previous studies and discuss the mechanisms and toxicological significance of metal-mediated epigenetic modifications.

Idiopathic pulmonary arterial hypertension (IPAH) is a progressive and fatal disease of unidentified pathogenesis. IPAH is pathologically characterized as sustained vasoconstriction and vascular remodeling of the pulmonary artery. In pulmonary arterial smooth muscle cells (PASMCs), an increase in cytosolic Ca2+ concentration ([Ca2+]cyt) triggers vasoconstriction and stimulates cell proliferation leading to vascular remodeling. However, dihydropyridine-type voltage-dependent Ca2+ channel blockers are only effective in very few patients with IPAH (<10%). It is unclear why dihydropyridine Ca2+ channel blockers are not therapeutically effective in a majority of IPAH patients. We have previously shown that extracellular Ca2+-sensing receptor (CaSR) is upregulated in PASMCs from IPAH patients, and it contributes to enhanced [Ca2+]cyt responses and augmented cell proliferation. In this study, the effects of dihydropyridine Ca2+ channel blockers on [Ca2+]cyt responses mediated by CaSR were examined in IPAH-PASMCs. Nifedipine (dihydropyridines) enhanced the CaSR-mediated increase in [Ca2+]cyt in IPAH-PASMCs, but not in PASMCs from normal subjects. Nicardipine (dihydropyridines) and Bay K 8644 (a dihydropyridine Ca2+ channel activator) also augmented the CaSR-mediated [Ca2+]cyt increase in IPAH-PASMCs. In contrast, non-dihydropyridine Ca2+ channel blockers such as diltiazem (benzothiazepines) and verapamil (phenylalkylamines) had no effect on the [Ca2+]cyt response in IPAH-PASMCs. Finally, in monocrotaline-induced pulmonary hypertensive rats, nifedipine caused further increase in right ventricular systolic pressure and thus right ventricular hypertrophy. In conclusion, dihydropyridine Ca2+ channel blockers could exacerbate symptoms of pulmonary hypertension in IPAH patients with upregulated CaSR in PASMCs.

Chronic alcohol consumption is a major public health problem that frequently leads to the development of liver steatosis, fibrosis, and eventually cirrhosis and hepatocellular carcinoma. Hyperhomocysteinemia is a pathological consequence of alcoholic liver disease (ALD) and is attributed to hepatic endoplasmic reticulum (ER) stress and insulin resistance. However, the regulatory function of nuclear receptors in ALD associated with dysregulation of homocysteine metabolism remains largely unknown. Nuclear receptor small heterodimer partner (SHP, NROB2) is a pleiotropic transcriptional repressor involved in regulating various metabolic path-ways in the liver. This study investigated a critical role of SHP in alcohol-induced hyperhomocysteinemia. . The expression and enzymatic activities of betaine-homocysteine S-methyltransferase (BHMT) and cystathionine y -lyase (CTH) were significantly increased in the liver of SHP- knockout (SKO) mice as compared to the wild-type mice. The substrates of BHMT and CTH, such as betaine, choline and cystathionine, were decreased in SKO liver while their products including hydrogen sulfide and cysteine were increased. However, methionine and homocysteine were not altered by SHP- deficiency, suggesting that the methionine cycle is activated in SKO mice. Forkhead box A (FOXA)- binding site was identified in both the BHMT and CTH promoters. Luciferase assay demonstrated that FOXAI, but not FOXA2, activated both BHMT and CTH promoters through the FOXA-binding site. Overexpression of FOXA1 induced BHMT and CTH expression in Hepal-6 cells, which was inhibited by SHP coexpression. Consistently, alcohol-induced hyperhomocysteinemia, and homocysteine-induced hepatic ER stress and glucose intolerance were abrogated in SKO mice. These novel findings identified SHP and FOXA1 as important regulators of hepatic homocysteine metabolism. Because hyper-homocysteinemia is a risk factor for cardiovascular disease and insulin resistance, and is often associated with ALD and metabolic syndrome, SHP and FOXA1 could be used as potential targets for hyperhomocysteinemia and its related diseases. Taken together, these results shed light on the regulatory mechanism of homocysteine metabolism in the liver.

Taste disorder is one of the adverse effects of cancer chemotherapy resulting in a loss of appetite, leading to malnutrition and a decrease in the quality of life of the patient. Oxaliplatin, a platinum anticancer drug, has a critical role in colon cancer chemotherapy and is known to induce taste disorder. Here, we evaluated the taste functions in oxaliplatin-administered rats. Among the taste receptors, expression levels of T1R2, one of the sweet receptor subunits, increased in the circumvallate papillae of the oxaliplatin-administered rats. In a brief-access test, i.e., behavioral analysis of the taste response, oxaliplatin-administered rats showed a decreased response to sweet taste. However, we did not detect any differences in the plasma levels of zinc, number of taste cells, or morphology of taste buds between control and oxaliplatin-administered rats. In conclusion, the decreased response to sweet taste by oxaliplatin administration may be due to the upregulation of T1R2 expression.

The use of nanotechnology has increased over the past 10 years, and various nanomaterials with a wide range of applications have been developed. Carbon nanotubes (CNTs), which are cylindrical molecules consisting of hexagonally arranged carbon atoms, are nanomaterials with high utility. Recently, applications of single-walled CNT (SWCNT) in the medical field for drug-delivery and as gene-delivery agents have been proposed. Due to its structural characteristics and physicochemical properties, the inhalation of SWCNT could be considered as one route for targeted drug delivery into the lungs. Therefore, it is necessary to investigate the effects of SWCNT on the physiological state and response of the cells upon delivery into the lung. We clarified the different response of two carcinoma cell lines to SWCNT exposure, and determined these differences may be due to different cell functions. Furthermore, SWCNT exposure resulted in a global downregulation of stress-responsive genes in normal human bronchial epithelial cells, thereby indicating that the factors involved in the stress responses were not activated by SWCNT. We then tried to ascertain the possible effect of SWCNT on the fate of drugs delivered with SWCNT. Exposure to SWCNT down-regulated the mRNA expression and enzymatic activity of CYP1A1 and CYP1B1 by preventing the binding of activated aryl hydrocarbon receptors to the enhancer region of these genes. This review provides basic information for the prediction of human responses to SWCNT exposure by inhalation, and in its use as a drug delivery carrier.

Naturally occurring inorganic arsenic is known to increase the risk of cancers of the skin and several other organs, including the urinary bladder, lung, and liver. Epidemiological studies have also indicated that gestational arsenic exposure is associated with increased incidences of cancers in several organs, including the bladder and liver, in adulthood. Previous studies have shown that epigenetic changes are involved in arsenic-induced carcinogenesis. Among epigenetic changes, DNA methylation changes that are specific to arsenic-induced tumors would be useful for distinguishing such tumors from tumors induced by other factors and for clarifying arsenic carcinogenesis. It has been reported that gestational arsenic exposure of C3H mice, whose males tend to spontaneously develop liver tumors, increases the incidence of tumors in the male offspring. Using the same experimental protocol, we found a number of regions where the DNA methylation status was altered in the liver tumors compared with the normal liver tissues by the methylated DNA immunoprecipitation (MeDIP)-CpG island microarray method. Among such regions, we demonstrated using real-time methylation-specific PCR and bisulfite sequencing that a gene body region of the oncogene Fosb underwent alteration in DNA methylation following gestational arsenic exposure. We also showed that the Fosb expression level significantly increased following gestational arsenic exposure. These findings suggest that the DNA methylation status of the Fosb region is implicated in tumor augmentation and can also be utilized for characterizing tumors induced by gestational arsenic exposure.

Collagen peptides, including glucosamine, are well-known functional food materials that act on bone and cartilage tissues. Collagen peptides are used at a volume of about 6,000 tons per year as a raw material in Japan. Evidence for the action of collagen peptides for both bone and cartilage tissues has accumulated both at basic research level (in vivo and in vitro ) and clinically. To confirm the clinical effect of these peptides and clearly identify their mechanism of action at the molecular level, further clinical studies comprising disease-free subjects, alongside basic research studies, are required.

The National Aeronautics and Space Administration has announced a plan to establish a manned colony on the surface of the moon, and our country, Japan, has declared its participation. The surface of the moon is covered with soil called lunar regolith, which includes fine particles. It is possible that humans will inhale lunar regolith if it is brought into the spaceship. Therefore, an evaluation of the pulmonary effects caused by lunar regolith is important for exploration of the moon. In the present study, we examine the cellular effects of lunar regolith simulant, whose components are similar to those of lunar regolith. We focused on the chemical component and particle size in particular. The regolith simulant was fractionated to < 10 μm, < 25 μm and 10-25 μm by gravitational sedimentation in suspensions. We also examined the cellular effects of fine regolith simulant whose primary particle size is 5.10 μm. These regolith simulants were applied to human lung carcinoma A549 cells at concentrations of 0.1 and 1.0 mg/ml. Cytotoxicity, oxidative stress and immune response were examined after 24 h exposure. Cell membrane damage, mitochondrial dysfunction and induction of Interleukin-8 (IL-8) were observed at the concentration of 1.0 mg/ml. The cellular effects of the regolith simulant at the concentration of 0.1 mg/ml were small, as compared with crystalline silica as a positive control. Secretion of IL-1β and tumor necrosis factor-α (TNF-α) was observed at the concentration of 1.0 mg/ml, but induction of gene expression was not observed at 24 h after exposure. Induction of cellular oxidative stress was small. Although the cellular effects tended to be stronger in the < 10 μm particles, there was no remarkable difference. These results suggest that the chemical components and particle size have little relationship to the cellular effects of lunar regolith simulant such as cell membrane damage, induction of oxidative stress and proinflammatory effect.

Monosodium glutamate (MSG) is known to provide the umami taste in the food. We have recently reported that glutamate has the potential to protect the small intestine against non-steroidal anti-inflammatory drugs (NSAIDs)-induced lesions in rats. In this paper, we examined this protective effect using sodium loxoprofen, one of the NSAIDs frequently used in Asian countries, to determine whether MSG accelerates the healing of loxoprofen-induced small intestinal lesions in rats. Loxoprofen at 60 mg/kg caused hemorrhagic lesions in the small intestine, mainly in the jejunum and ileum. These lesions spontaneously healed within 7 days, but this healing process was delayed by repeated administration of loxoprofen at low doses (10, 30 mg/kg) for 5 d after lesion induction. The healing-impairment action of loxoprofen was accompanied by the down-regulation of vascular endothelium-derived growth factor (VEGF) expression and an angiogenic response. The impaired healing caused by loxoprofen was significantly restored by co-treatment with a diet containing 5% MSG for 5 d, accompanied by the enhancement of VEGF expression and angiogenesis. We suggest that daily intake of MSG not only protects the small intestine against NSAIDs-induced damage but also exerts healing-promoting effects on these lesions.