Generation of Tetrafluoroethylene–Propylene Elastomer-Based Microfluidic Devices for Drug Toxicity and Metabolism Studies

フッ素系エラストマー素材を用いた肝臓チップの開発と薬物代謝・毒性試験への応用. 京都大学プレスリリース. 2021-09-16.Drug testing on miniatured livers. 京都大学プレスリリース. 2021-09-17.Polydimethylsiloxane (PDMS) is widely used to fabricate microfluidic organs-on-chips. Using these devices (PDMS-based devices), the mechanical microenvironment of living tissues, such as pulmonary respiration and intestinal peristalsis, can be reproduced in vitro. However, the use of PDMS-based devices in drug discovery research is limited because of their extensive absorption of drugs. In this study, we investigated the feasibility of the tetrafluoroethylene–propylene (FEPM) elastomer to fabricate a hepatocyte-on-a-chip (FEPM-based hepatocyte chip) with lower drug absorption. The FEPM-based hepatocyte chip expressed drug-metabolizing enzymes, drug-conjugating enzymes, and drug transporters. Also, it could produce human albumin. Although the metabolites of midazolam and bufuralol were hardly detected in the PDMS-based hepatocyte chip, they were detected abundantly in the FEPM-based hepatocyte chip. Finally, coumarin-induced hepatocyte cytotoxicity was less severe in the PDMS-based hepatocyte chip than in the FEPM-based hepatocyte chip, reflecting the different drug absorptions of the two chips. In conclusion, the FEPM-based hepatocyte chip could be a useful tool in drug discovery research, including drug metabolism and toxicity studies

Differential gene expression profiles in neurons generated from lymphoblastoid B-cell line-derived iPS cells from monozygotic twin cases with treatment-resistant schizophrenia and discordant responses to clozapine

Schizophrenia is a chronic psychiatric disorder with complex genetic and environmental origins. While many antipsychotics have been demonstrated as effective in the treatment of schizophrenia, a substantial number of schizophrenia patients are partially or fully unresponsive to the treatment. Clozapine is the most effective antipsychotic drug for treatment-resistant schizophrenia; however, clozapine has rare but serious side-effects. Furthermore, there is inter-individual variability in the drug response to clozapine treatment. Therefore, the identification of the molecular mechanisms underlying the action of clozapine and drug response predictors is imperative. In the present study, we focused on a pair of monozygotic twin cases with treatment-resistant schizophrenia, in which one twin responded well to clozapine treatment and the other twin did not. Using induced pluripotent stem (iPS) cell-based technology, we generated neurons from iPS cells derived from these patients and subsequently performed RNA-sequencing to compare the transcriptome profiles of the mock or clozapine-treated neurons. Although, these iPS cells similarly differentiated into neurons, several genes encoding homophilic cell adhesion molecules, such as protocadherin genes, showed differential expression patterns between these two patients. These results, which contribute to the current understanding of the molecular mechanisms of clozapine action, establish a new strategy for the use of monozygotic twin studies in schizophrenia research

Correction to “A Microporous Aluminosilicate with 12‑, 12‑, and 8‑Ring Pores and Isolated 8‑Ring Channels”

Correction to “A Microporous Aluminosilicate with 12‑, 12‑, and 8‑Ring Pores and Isolated 8‑Ring Channels

A Microporous Aluminosilicate with 12‑, 12‑, and 8‑Ring Pores and Isolated 8‑Ring Channels

Synthesis of new zeolites with controlled pore architectures is important in the field of catalysis and separation related to chemical transformation, environmental protection, and energy-saving. Zeolites containing channels of different sizes in the same framework have been desirable. We report here the synthesis and structure of a novel aluminosilicate zeolite (designated as YNU-5), the first zeolite containing interconnected 12-, 12-, and 8-ring pores, as well as independent straight 8-ring channels. The synthesis procedure is quite simple and consists of conventional hydrothermal conditions as well as readily available starting materials. The framework structure is stable enough and Si/Al ratio is controllable between 9 and 350. Determination of the crystal structure is performed by utilizing X-ray diffraction-based techniques, revealing 9 independent tetrahedrally coordinated atoms. This robust structure is expected to be industrially valuable and several unusual combinations of composite building units are of considerable interest in an academic sense. The new zeolite YNU-5 is promising catalyst for the production of useful light olefins such as propylene and butylenes in the dimethyl ether-to-olefin reaction, when the Si/Al ratio is properly tuned by dealumination through simple acid treatments

A Microporous Aluminosilicate with 12‑, 12‑, and 8‑Ring Pores and Isolated 8‑Ring Channels

Synthesis of new zeolites with controlled pore architectures is important in the field of catalysis and separation related to chemical transformation, environmental protection, and energy-saving. Zeolites containing channels of different sizes in the same framework have been desirable. We report here the synthesis and structure of a novel aluminosilicate zeolite (designated as YNU-5), the first zeolite containing interconnected 12-, 12-, and 8-ring pores, as well as independent straight 8-ring channels. The synthesis procedure is quite simple and consists of conventional hydrothermal conditions as well as readily available starting materials. The framework structure is stable enough and Si/Al ratio is controllable between 9 and 350. Determination of the crystal structure is performed by utilizing X-ray diffraction-based techniques, revealing 9 independent tetrahedrally coordinated atoms. This robust structure is expected to be industrially valuable and several unusual combinations of composite building units are of considerable interest in an academic sense. The new zeolite YNU-5 is promising catalyst for the production of useful light olefins such as propylene and butylenes in the dimethyl ether-to-olefin reaction, when the Si/Al ratio is properly tuned by dealumination through simple acid treatments

A Microporous Aluminosilicate with 12‑, 12‑, and 8‑Ring Pores and Isolated 8‑Ring Channels

Synthesis of new zeolites with controlled pore architectures is important in the field of catalysis and separation related to chemical transformation, environmental protection, and energy-saving. Zeolites containing channels of different sizes in the same framework have been desirable. We report here the synthesis and structure of a novel aluminosilicate zeolite (designated as YNU-5), the first zeolite containing interconnected 12-, 12-, and 8-ring pores, as well as independent straight 8-ring channels. The synthesis procedure is quite simple and consists of conventional hydrothermal conditions as well as readily available starting materials. The framework structure is stable enough and Si/Al ratio is controllable between 9 and 350. Determination of the crystal structure is performed by utilizing X-ray diffraction-based techniques, revealing 9 independent tetrahedrally coordinated atoms. This robust structure is expected to be industrially valuable and several unusual combinations of composite building units are of considerable interest in an academic sense. The new zeolite YNU-5 is promising catalyst for the production of useful light olefins such as propylene and butylenes in the dimethyl ether-to-olefin reaction, when the Si/Al ratio is properly tuned by dealumination through simple acid treatments

Increased behavioral and neuronal responses to a hallucinogenic drug in PACAP heterozygous mutant mice.

Accumulating evidence from human genetic studies implicates the pituitary adenylate cyclase-activating polypeptide (PACAP) gene as a risk factor for psychiatric disorders, including schizophrenia and stress-related diseases. Mice with homozygous disruption of the PACAP gene display profound behavioral and neurological abnormalities that are ameliorated with the atypical antipsychotic and dopamine D2 and serotonin (5-HT)2 antagonist risperidone and the 5-HT2 receptor antagonist ritanserin; however, the underlying mechanisms remain unknown. Here, we investigated if PACAP heterozygous mutant (PACAP(+/-)) mice, which appear behaviorally normal, are vulnerable to aversive stimuli. PACAP(+/-) mice were administered a 5-HT2 receptor agonist, (±)-2,5-dimethoxy-4-iodoamphetamine (DOI), a hallucinogenic drug, and their responses were compared with the littermate wild-type mice. After DOI injection, PACAP(+/-) mice showed increased head-twitch responses, while their behavior was normal after saline. DOI induced deficits in sensorimotor gating, as determined by prepulse inhibition, specifically in PACAP(+/-) mice. However, other 5-HT2 receptor-dependent responses, such as corticosterone release and hypothermia, were similarly observed in PACAP(+/-) and wild-type mice. c-Fos expression analysis, performed in various brain regions, revealed that the DOI-induced increase in the number of c-Fos-positive cells was more pronounced in 5-HT2A receptor-negative cells in the somatosensory cortex in PACAP(+/-) mice compared with wild-type mice. These results indicate that PACAP(+/-) mice exhibit specific vulnerability to DOI-induced deficits in cortical sensory function, such as exaggerated head-twitch responses and sensorimotor gating deficits. Our findings provide insight into the neural mechanisms underlying impaired behavioral responses in which 5-HT2 receptors are implicated

β-Arrestin1 and 2 differentially regulate PACAP-induced PAC1 receptor signaling and trafficking

<div><p>A pituitary adenylate cyclase-activating polypeptide (PACAP)-specific receptor, PAC1R, is coupled with multiple signal transduction pathways including stimulation of adenylate cyclase, phospholipase C and extracellular-signal regulated kinase (ERK)1/2. PAC1R has been shown to exert its long-lasting and potent signals via β-arrestin1 and β-arrestin2. However, the precise roles of the two β-arrestin isoforms in PACAP-PAC1R signaling remain unclear. Here we examined the interaction between the two β-arrestin isoforms and PAC1R, β-arrestin-dependent PAC1R subcellular localization and ERK1/2 activation. Upon PACAP stimulation, although PAC1R similarly interacted with β-arrestin1 and β-arrestin2 in HEK293T cells, the complex of PAC1R and β-arrestin2 was translocated from the cell surface into cytosol, but that of β-arrestin1 remained in the cell surface regions in HeLa cells and mouse primary cultured neurons. Silencing of β-arrestin2 blocked PACAP-induced PAC1R internalization and ERK1/2 phosphorylation, but silencing of β-arrestin1 increased ERK1/2 phosphorylation. These results show that β-arrestin1 and β-arrestin2 exert differential actions on PAC1R internalization and PAC1R-dependent ERK1/2 activation, and suggest that the two β-arrestin isoforms may be involved in fine and precise tuning of the PAC1R signaling pathways.</p></div

Time-lapse cell imaging showing PAC1R and β-arrestin coupling and translocation in HeLa cells.

<p>HeLa cells were transfected with the indicated combinations of plasmid vectors. <b>(A and B)</b> Representative images of NanoBiT luminescence at 3, 15, 30 and 60 min after stimulation with 1 μM PACAP. <b>(C and D)</b> Representative time-dependent changes of line-scan images for 60 min after stimulation with 1 μM PACAP. <b>(E and F)</b> Time course of changes in luminescence intensity at the vicinity of the plasma membrane (membrane) and the cytoplasm for 60 min after stimulation with 1 μM PACAP in HeLa cells. Scale bars, 10 μm. β-arr1, β-arrestin1; β-arr2, β-arrestin2. Values are mean ± SEM (n = 3–5). *<i>p</i> < 0.05 vs. cytoplasm, repeated measure two-way ANOVA followed by Fisher-PLSD test. See also <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0196946#pone.0196946.s004" target="_blank">S1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0196946#pone.0196946.s005" target="_blank">S2</a> Movies.</p