Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by selective motor neuron cell death. A GGGGCC hexanucleotide repeat expansion (HRE) within the chromosome 9 open reading frame 72 (C9orf72) gene is a major causative factor in ALS. This abnormal HRE triggers five types of dipeptide repeat protein (DPR), each composed of two alternating amino acid expressions. Among the DPRs, arginine-rich Poly-PR localizes predominantly to the nucleus, exerting particularly strong toxicity on motor and cortical neurons. Several mechanisms have been proposed for poly-PR–induced neurotoxicity. In this study, poly-PR–expressing NSC34 motor neuron-like cells showed an increase in oxidative stress. Fibroblast growth factor receptor 1 (FGFR1) is known to promote neurogenesis and inhibit apoptosis in neurons. However, its neuroprotective effects against DPR-induced toxicity have not been previously reported. Here, we demonstrated that FGFR1 activation reduced oxidative stress by upregulating nuclear factor erythroid 2-related factor 2 (NRF2) expression. Furthermore, we propose that the increase in NRF2 through FGFR1 activation may result from the alleviation of protein translation impairment. Overall, these findings suggest that FGFR1 activation provides neuroprotection against poly-PR toxicity and may represent a potential therapeutic strategy for ALS.

QO58 (5-(2,6-dichloro-5-fluoropyridin-3-yl)-3-phenyl-2-(trifluoromethyl)-1H-[1,5-a] pyrimidin-7-one) is currently used as a specific activator of the Kv7 (KCNQ) family of K⁺ channels. Here, we report an unexpected potentiating effect of this drug on nicotinic acetylcholine receptors. We recorded the whole-cell responses to the rapid application of nicotine with the Cs⁺-based pipette solution in intracardiac ganglion neurons freshly dissociated from the rat heart. Nicotine-induced inward currents were concentration-dependently blocked by mecamylamine, but not by 1 μM atropine at a holding potential of −60 mV. While the application of QO58 per se evoked a persistent inward current at this holding potential, 10 μM QO58 potentiated the peak amplitude of the nicotine-induced current. The QO58-induced inward currents were inhibited by the Kv7 channel blockers XE991 and Ba²⁺, but not by mecamylamine. On the other hand, the nicotine-induced current potentiated by QO58 was fully inhibited by mecamylamine. The facilitatory action of QO58 on the nicotinic response was unaffected by Ba²⁺. QO58 did not affect the reversal potential of the nicotine-induced current. QO58 apparently shifted the concentration–response curve of nicotine to the left. The half-maximal effective concentrations for nicotine in the absence and presence of 10 μM QO58 were 10.2 and 4.3 μM, respectively. These results suggest that QO58 acts as a positive allosteric modulator of nicotinic acetylcholine receptors. Given the prevalence of nicotinic receptor signaling, the present observations should be considered in future studies on the roles of Kv7 channels in the function of neural circuits and diseases.

Skin pigmentation is a widely recognized side effect of cancer chemotherapy that can negatively affect patient QOL. However, although numerous case reports have documented pigmentation caused by anticancer drugs, the precise mechanisms remain unclear. Among such pigmentation, that induced by 5-fluorouracil (5-FU) has garnered considerable attention, whereas reports on irinotecan-induced pigmentation are comparatively limited. In this study, we investigated the pigmentation-related effects of irinotecan in colored hairless mice. Mice received intraperitoneal injections of 20 mg/kg irinotecan, and we subsequently examined the pigmentation of the plantar and buttock regions. The results indicated that irinotecan specifically induces pigmentation in the plantar region, with no pigmentation observed on the buttocks. In contrast, pigmentation was noted on the buttocks, although not in the plantar region, in the control mice treated with 5-FU and cytarabine. Furthermore, irinotecan treatment promoted a marked elevation in the expression of tyrosinase, cAMP response element binding protein (CREB), and microphthalmia-associated transcription factor (MITF) in the plantar region, whereas no significant changes were observed in the buttocks. These findings indicate that irinotecan leads to site-specific pigmentation in the sole of the foot, thereby highlighting the potential for anticancer drugs to cause localized pigmentation.

Soy isoflavonoids were applied to commercially available baker’s yeast in vitro to find metabolites. Tyrosol, an ingredient in olive oil and wine, and tryptophol were found in the culture media. To test whether tyrosol is a metabolite of soy isoflavonoids, we prepared 2,4-dideuterated equol and applied it to yeast. According to LC-MS analysis of the culture media, deuterated tyrosol was not produced. Therefore, tyrosol is assumed to be a tyrosine metabolite of yeast known as the Ehrlich pathway. We then evaluated the in vitro activities of the 2 amino acid-derived alcohols. Both tyrosol and tryptophol similarly showed anti-inflammatory activity, as evaluated by monocyte chemoattractant protein-1 in 3T3-L1 murine adipocytes in vitro. Our results suggested that the amino acid-derived alcohols may contribute to the anti-inflammatory activity of fermented foods.

Lysophpsphospholipids (LPLs) are lipid mediators involved in various physiological functions. In daily diets, people consume large amounts of various lipids, including LPLs. Exogenous dietary LPLs initially affect epithelial cells and, finally, the entire colon and may be linked to the onset and prevention of colonic diseases, including inflammatory bowel disease. However, the effects of exogenous LPLs on epithelial cells remain poorly understood. In this study, we used HT-29, a human colon cancer-derived epithelial cell, to evaluate the effects of LPLs on epithelial cells under normal and inflammatory states. In the absence of lipopolysaccharide (LPS), several LPLs decreased interleukin-8 (IL-8) secretion from HT-29 cells in the following order of potency based on the reduction ratio at the highest concentration: lysophosphatidylglycerol > lysophosphatidylcholine > lysophosphatidyletanolamine > lysophosphatidylserine. In the presence of LPS, only lysophosphatidylinositol (LPI) decreased the IL-8 secretion induced by LPS. Focusing on the G protein-coupled receptors (GPCRs) that LPI acts on, PSN375963 and AS1269574, GPR119 agonists, decreased the IL-8 secretion induced by LPS. It is speculated that IL-8 secretion was reduced by LPI via GPR119 signaling under non-inflammatory conditions. Although the detailed mechanism remains to be elucidated, the findings that LPLs, except for LPI, have inhibitory effects and that LPI has an inhibitory/anti-inflammatory effect on IL-8 secretion will help to elucidate the mechanism on the onset of colonic diseases and the planning of treatment methods in the future.

Although Sanggenol L (SL), derived from the root bark of Morus alba, has hepatoprotective, neuroprotective, and antitumor effects, the antitumor mechanism of SL remains unclear to date. Thus, in the current work, the apoptotic mechanisms of SL were investigated in HepG2 and Huh hepatocellular carcinoma (HCC) cells in relation to leucine-rich repeat containing G protein-coupled receptor 5 (LGR5)/β-catenin and miR134 signaling axis. Herein, SL significantly incremented cytotoxicity, sub-G1 population, and the number of terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) positive apoptotic bodies and also inhibited proliferation in HCCs. Consistently, SL activated pro-Caspase7 and pro-Caspase3 and induced the cleavage of Poly ADP-ribose polymerase (PARP) in HCCs. Of note, the pivotal role of LGR5/β-catenin signaling was verified in SL-induced apoptosis in LGR5 overexpressed AML-12 cells and LGR5 depleted HepG2 cells. Furthermore, SL upregulated miR134 expression levels in HepG2 cells, while miR134 inhibitors disturbed the capacity of SL to cleave PARP and pro-Caspase3 in HepG2 cells. Taken together, our findings highlight evidence that inhibition of the LGR5/β-catenin axis and upregulation of miR134 play critical roles in SL-induced apoptosis in HCCs.

In Japan, S-1 is used as adjuvant chemotherapy for pancreatic cancer. Neutropenia during S-1 chemotherapy is reported to be an independent predictor of prolonged survival in patients with advanced gastric cancer. However, this is unclear in pancreatic cancer. This study aimed to examine the effect of severe neutropenia caused by S-1 adjuvant chemotherapy on pancreatic cancer prognosis: overall survival (OS) and recurrence-free survival (RFS), and the potential effect of the duration from surgery to S-1 administration on OS and RFS. This single-center, retrospective, observational study included patients who newly received S-1 adjuvant chemotherapy after curative resection of pancreatic cancer at the Japanese Red Cross Kyoto Daini Hospital between January 1, 2016, and September 30, 2020. Of the 43 patients, 9 had grade 3 or higher neutropenia (G3 group) and had a significantly longer median OS than the other 34 (non-G3 group) did. The median RFS of the G3 group was longer than that of the non-G3 group. The median time from surgery to S-1 administration was significantly shorter in the G3 group than in the non-G3 group. Cox proportional hazards regression analysis revealed that duration from surgery to S-1 administration <51 d (hazard ratio: 0.375, 95% confidence interval: 0.154–0.914, p = 0.031) and occurrence of grade 3 neutropenia (hazard ratio: 0.198, 95% confidence interval: 0.046–0.860, p = 0.031) were significantly associated with prolonged OS. In conclusion, initiating S-1 adjuvant chemotherapy early after surgery and the occurrence of grade 3 neutropenia may improve pancreatic cancer prognosis.

Metallothionein (MT) is a small-molecule protein that functions in essential trace element homeostasis. Among MT isoforms, MT3 is involved in neuronal activity, and its expression is reported to be decreased in patients with neurodegenerative conditions such as Alzheimer’s disease; however, only a few effective drugs have been reported to induce MT3 expression. In this study, we evaluated existing drugs for the induction of MT3 expression in the neuronal cell line of ReNcell CX cells. Using recombinant proteins of MT isoforms with the 3× Flag tag, we performed Western blotting (WB) with the primary antibodies against MT3 or Flag tag, and this method of WB for MT3 was confirmed specifically to detect the MT3 protein. We treated ReNcell CX cells with several HIF-PH inhibitors and evaluated MT3 expression via real-time RT-PCR. We found that FG4592 significantly enhanced MT3 expression at both RNA and protein levels. FG4592 treatment increased the amount of hypoxia-inducible factor 1 alpha (HIF1α) binding to the MT3 promoter. These findings indicate that FG4592 induces MT3 expression via increased HIF1α. In conclusion, we found FG4592 to be an endogenous MT3 inducer in the cells of the nervous system in this study. The findings of this study are expected to lead to the development of new MT3-inducing drugs for neurodegenerative diseases based on FG4592.

The effects of thirteen Vaughn Williams class I antiarrhythmic drugs on the α₁-adrenergic receptor-mediated contraction were examined in thoracic aorta tissue preparations isolated from the guinea pig. Cibenzoline, quinidine, aprindine, and ranolazine, as well as prazosin, inhibited the phenylephrine-induced contraction with pA₂ values of 5.64, 5.59, 5.61, 5.08, and 8.50, respectively, but not prostaglandin F_2α-induced. These drugs reduced the staining of the smooth muscle layer by fluorescent prazosin. Propafenone inhibited the phenylephrine-induced contraction with an apparent pA₂ value of 5.31 and reduced the staining by fluorescent prazosin, but also inhibited the prostaglandin F_2α-induced contraction. Other class I antiarrhythmic drugs, disopyramide, pirmenol, procainamide, lidocaine, mexiletine, flecainide, pilsicainide, and GS-458967, affected neither the contraction by phenylephrine nor the fluorescent staining by prazosin. These results indicate that among the class I antiarrhythmic drugs, cibenzoline, aprindine, and propafenone, as well as quinidine and ranolazine, have α₁-adrenoceptor-blocking activity at therapeutically relevant concentrations.

Fluorescence imaging analysis was performed in cardiomyocytes from the sinus node, the orthotopic pacemaker, and the pulmonary vein, a potential ectopic pacemaker that may cause atrial fibrillation, focusing on the role of the Na⁺/Ca²⁺ exchanger (NCX). Isolated cardiomyocytes from the guinea pig pulmonary vein and sinus node showing automaticity were loaded with fluorescence probes for analysis. Inhibition of NCX by SEA0400 decreased the Ca²⁺ transient frequency in the pulmonary vein cardiomyocytes but not in the sinus node. The basal intracellular Ca²⁺ concentration, as well as the number of Ca²⁺ sparks in the subsarcolemmal region, was higher in the pulmonary vein cardiomyocytes than in the sinus node. By contrast, the intracellular Na⁺ concentration was not different between the pulmonary vein and sinus node cardiomyocytes. The equilibrium potential for NCX (E_NCX) was estimated to be less negative in the pulmonary vein cardiomyocytes than in the sinus node. In conclusion, the forward mode NCX is involved in spontaneous activity in the pulmonary vein cardiomyocytes but not in the sinus node; this is probably because the Ca²⁺ supply and the driving force for the forward mode NCX are both larger in the pulmonary vein cardiomyocytes than in the sinus node.

Carboxylesterase (CES) plays an important role in the metabolism of ester-containing drugs such as prodrugs and is highly expressed in the human intestine and liver. The ideal prodrug is barely hydrolyzed by human intestinal CES (CES2A1) but is extensively converted to an active drug by human hepatic CES (CES1A). It is, therefore, important to evaluate CES2A1-mediated hydrolysis during intestinal absorption. Unfortunately, Caco-2 cells, the most common enterocyte model for drug permeability, are not suitable for permeability studies of prodrugs due to their high and extremely low expression of CES1A and CES2A1, respectively. Previously, we have prepared CES2/Caco-2^CES1KD cells with reduced human CES1A and highly expressed CES2A1. In the present study, the metabolic and transport properties of CES2/Caco-2^CES1KD cells were characterized. The expression of transporters and metabolizing enzymes other than CESs was similar in CES2/Caco-2^CES1KD and Caco-2 cells. However, the expression of CES2A1 in CES2/Caco-2^CES1KD was about 7–10 fold higher than that of CES1A in Caco-2 cells and comparable to levels found in the human intestine. Hydrolysis during transport across cell monolayers was analyzed using ethyl and butyl esters of p-aminobenzoic acid (PABA). Ethyl PABA, a better substrate for CES1A than CES2A1, was similarly hydrolyzed in Caco-2 and CES2/Caco-2^CES1KD cell monolayers due to the high expression of CES2A1 in CES2/Caco-2^CES1KD cells. Butyl PABA, a good substrate for CES2A1, was substantially hydrolyzed in CES2/Caco-2^CES1KD cell monolayers, in contrast to negligible hydrolysis in Caco-2 cell monolayers. N-Acetylation of PABA derived from PABA esters showed similar activity in Caco-2 and CES2/Caco-2^CES1KD cell monolayers.

The non-canonical phosphorylation of the receptor tyrosine kinase ephrin type-A receptor 2 (EphA2) at Ser-897 plays crucial roles in tumor progression in a tyrosine kinase-independent manner. This phosphorylation is catalyzed by p90 ribosomal S6 kinase (RSK), a kinase downstream of extracellular signal-regulated kinase (ERK). We recently reported that stress-responsive kinase mitogen-activated protein kinase (MAPK)-activated protein kinase 2 (MK2), instead of ERK, regulates RSK under cellular stress conditions; however, the function of MK2 in ERK-activated cells is still unknown. We herein clarified that MK2 regulates the RSK-EphA2 axis in ERK-activated echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) lung cancer cells. In addition, an MK2 inhibitor blocked enhancements in cell motility induced by the constitutively activated RSK-EphA2 axis. The present results reveal the importance of MK2 in the ERK-activated non-canonical activation of EphA2.

Benzodiazepine (BZD) therapy has been associated with several side effects in hospitalized patients. We developed a protocol-based pharmacotherapy management (PBPM) to recommend BZD discontinuation for patients at high risk for postoperative delirium (PD) following cardiovascular surgery. This study investigated whether implementing PBPM affects BZD prescription trends among cardiovascular surgeons for PD non-high-risk patients. This single-center retrospective cohort study collected all prescription orders of BZD from June 1, 2018, to May 31, 2023, and these orders were divided into 2 periods: 2 years and 6 months before and after PBPM. Changes in BZD prescription trends for patients with non-high-risk of PD were analyzed using interrupted time series (ITS). Furthermore, all patients in the department of cardiovascular surgery were also investigated as supplementary analysis. ITS analysis revealed that there was a significant level change in BZD prescriptions (–20%, 95% confidence interval: –37 to –2.8, p = 0.023), and the slope exhibited a downward trend (–0.90%, 95% confidence interval: –1.9 to 0.07, p = 0.068) in PD non-high-risk patients. In all patients, the level change was –21% (95% confidence interval: –0.36 to –0.9, p = 0.004) and the slope change was –0.85% (95% confidence interval: –1.7 to –0.02, p = 0.045). These results suggest that PBPM implementation significantly reduced the BZD prescription rate among cardiovascular surgeons for patients with a non-high-risk of PD. The alteration in prescription trends might be attributed to pharmacist interventions targeting patients with a high risk of PD, which influenced the prescribing behavior of cardiovascular surgeons.

Itch is described as an unpleasant sensation, and chronic itch, such as that in atopic dermatitis (AD), often decreases a patient’s QOL. There are few effective treatments for various chronic pruritic disorders that are not limited to inflammation. Selective serotonin reuptake inhibitors (SSRIs) are antidepressants used to treat some chronic pruritus disorders. However, there is little evidence from clinical and basic studies using animal models. In this study, we found that paroxetine suppressed acute and chronic itch in mouse models. Single administration of paroxetine (10 mg/kg) inhibited scratching behavior caused by histamine-dependent or histamine-independent itch. Moreover, paroxetine (10 mg/kg) inhibited spontaneous scratching behavior in AD model using NC/Nga mice without affecting locomotor function. These results suggest that paroxetine suppresses chronic itch caused by AD via histamine-dependent and -independent pathways. This study provides one of the few pieces of evidence that SSRIs suppress itch.

Bacteria have a stringent response system mediated by guanosine pentaphosphate and tetraphosphate ((p)ppGpp), which suppresses the expression of genes involved in cell growth and promotes the expression of genes involved in nutrient uptake and metabolism under nutrient-limited stress. In environments with limited availability of iron, an essential trace element, bacteria generally produce and secrete siderophores to efficiently utilize water-insoluble ferric iron (Fe³⁺) in the environment. In Vibrio parahaemolyticus, Fur (iron-responsive repressor) and RyhB (Fur-regulated small RNA) regulate the expression of genes involved in the utilization of vibrioferrin (VF), a siderophore produced by this bacterium. In this study, we examined whether (p)ppGpp is also involved in regulating the expression of genes related to the VF utilization system. Results of the chrome azurol S plate assay revealed that the strain in which 3 (p)ppGpp synthetases were deleted (∆relA∆spoT∆relV) produced less VF than the parental strain. Growth test results showed that the growth rate of ∆relA∆spoT∆relV in an iron-limited medium was suppressed compared with that of the parental strain but was restored with the addition of VF. Furthermore, RT-quantitative (q)PCR results showed that the expression levels of pvsA (VF biosynthesis gene) and pvuA2 (ferric VF receptor gene) in ∆relA∆spoT∆relV under iron limitation were significantly reduced compared with those in the parental strain. Western blot results demonstrated that the expression level of PvuA2 in ∆relA∆spoT∆relV was lower than that in the parental strain. These results suggest that (p)ppGpp promotes the expression of genes related to VF biosynthesis and the ferric VF uptake system under iron limitation.