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In the early stages of drug discovery, adequate evaluation of the potential drug–drug interactions (DDIs) of drug candidates is important. Several CYP3A activators are known to lead to underestimation of DDIs. These compounds affect midazolam 1'-hydroxylation but not midazolam 4-hydroxylation. We used both metabolic reactions of midazolam to evaluate the activation and inhibition of CYP3A activators simultaneously. For our CYP inhibition assay using cocktail probe substrates, simultaneous liquid chromatography-tandem mass spectrometry monitoring of 1'-hydroxymidazolam and 4-hydroxymidazolam for CYP3A was established in addition to monitoring of 4-hydroxydiclofenac and 1'-hydroxybufuralol for CYP2C9 and CYP2D6. The results of our cocktail inhibition assay were well correlated with those of a single inhibition assay, as were the estimated inhibition parameters for typical CYP3A inhibitors. In our assay, a proprietary compound that activated midazolam 1'-hydroxylation and tended to inhibit 4-hydroxylation was evaluated along with known CYP3A activators. All compounds were well characterised by comparison of the results of midazolam 1'- and 4-hydroxylation. In conclusion, our CYP cocktail inhibition assay can detect CYP3A activation and assess the direct and time-dependent inhibition potentials for CYP3A, CYP2C9, and CYP2D6. This method is expected to be very efficient in the early stages of drug discovery. [ABSTRACT FROM AUTHOR]

Individuals with an objective decrease in salivary flow (objective dry mouth) may not be aware of subjective dry mouth (xerostomia). However, no clear evidence exists to explain the discordance between subjective and objective dry mouth. Therefore, this cross-sectional study aimed to assess the prevalence of xerostomia and decreased salivary flow among community-dwelling elderly adults. In addition, this study assessed several potential demographic and health status determinants of the discrepancy between xerostomia and reduced salivary flow. The 215 participants in this study were community-dwelling older people aged 70 years and above who underwent dental health examinations between January-February 2019. Symptoms of xerostomia were collected in the form of a questionnaire. The unstimulated salivary flow rate (USFR) was measured by a dentist using visual inspection. The stimulated salivary flow rate (SSFR) was measured using the Saxon test. We identified 19.1% of participants as having mild-severe USFR decline with xerostomia and 19.1% as having mild-severe USFR decline without xerostomia. Additionally, 26.0% of participants had low SSFR and xerostomia, and 40.0% had low SSFR without xerostomia. Except for the age trend, no factors could be associated with the discordance between USFR measurement and xerostomia. Furthermore, no significant factors were associated with the discordance between the SSFR and xerostomia. However, females were significantly associated (OR = 2.608, 95% CI = 1.174–5.791) with low SSFR and xerostomia, as compared to males. Age was a factor that was also significantly associated (OR = 1.105, 95% CI = 1.010–1.209) with low SSFR and xerostomia. Our findings indicate that approximately 20% of the participants had low USFR without xerostomia, and 40% had low SSFR without xerostomia. This study showed that age, sex, and the number of medications may not be factors in the discrepancy between the subjective feeling of dry mouth and reduced salivary flow. [ABSTRACT FROM AUTHOR]

Linzagolix is an orally available gonadotropin-releasing hormone antagonist used to treat sex-hormone-dependent diseases in women. This study aimed to investigate drug-drug interactions between linzagolix and iron/calcium ions in the intended clinical setting by conducting pharmacokinetic studies in vitro and in rats. Insoluble precipitate formation with metal ions was evaluated by measuring linzagolix concentrations in four types of bio-relevant dissolution media (fasted/fed state simulated gastric fluid and fasted/fed state simulated gastric fluid version 2), and chelate complex formation with metal ions was evaluated by release of linzagolix from a cellulose membrane sac. In these in vitro studies, linzagolix showed no potential for insoluble precipitate formation under fasted/fed conditions and no chelate complex formation in the presence of metal ions. In rats, the plasma concentration-time profiles of linzagolix and iron ion were similar regardless of whether they were administered with or without ferrous sulphate and linzagolix choline at clinically relevant doses. Thus, linzagolix and iron ion had no effect on each other's absorption in vivo. In conclusion, linzagolix is unlikely to cause clinically relevant drug-drug interactions by chelating metal ions according to the results of in vitro and in vivo studies. [ABSTRACT FROM AUTHOR]

The effects of itraconazole on the pharmacokinetics of rovatirelin were investigated in an open‐label, single‐sequence drug‐drug interaction study in 16 healthy subjects. Subjects were administered a single oral dose of rovatirelin (1.6 mg) on day 1 and day 15. From day 8 through 16, subjects received daily oral doses of itraconazole (200 mg/day). Concentrations of rovatirelin and (thiazolylalanyl)methylpyrrolidine (TAMP), the major metabolite of rovatirelin formed by cytochrome P450 (CYP) 3A4/5, were determined in plasma and urine. Pharmacokinetic parameters were used to evaluate the drug‐drug interaction potential of rovatirelin as a victim. With coadministration, maximum concentration (Cmax) and area under the concentration‐time curve extrapolated to infinity (AUCinf) of rovatirelin increased 3.05‐fold and 2.82‐fold, respectively, and the 90% confidence intervals of the ratios for Cmax (2.64‐3.52) and AUCinf (2.47‐3.23) did not fall within the 0.8‐1.25 boundaries. Urinary excretion of rovatirelin increased at almost the same ratio as the AUCinf ratio with coadministration; however, renal clearance did not change. Cmax, AUCinf, and urinary excretion of TAMP were decreased by coadministration. Itraconazole has the potential to inhibit drug transport via intestinal P‐glycoprotein (P‐gp) and breast cancer resistance protein (BCRP); therefore, substrate assessments of rovatirelin for the 2 transporters were evaluated using Caco‐2 cell monolayers. In vitro studies showed that rovatirelin is a substrate for P‐gp but not for BCRP. The current study shows that itraconazole's effect on rovatirelin pharmacokinetics is mediated through inhibition of CYP3A4/5 and intestinal P‐gp. [ABSTRACT FROM AUTHOR]

The mass balance, pharmacokinetics and metabolism of rovatirelin were characterised in healthy male subjects after a single oral dose of [14C]rovatirelin. [14C]Rovatirelin was steadily absorbed, and the peak concentrations of radioactivity and rovatirelin were observed in plasma at 5–6 h after administration. The AUCinf of radioactivity was 4.9-fold greater than that of rovatirelin. Rovatirelin and its metabolite (thiazoylalanyl)methylpyrrolidine (TAMP) circulated in plasma as the major components. The total radioactivity recovered in urine and faeces was 89.0% of the administered dose. The principal route of elimination was excretion into faeces (50.1% of the dose), and urinary excretion was the secondary route (36.8%). Rovatirelin was extensively metabolised to 20 metabolites, and TAMP was identified as the major metabolite in plasma and excreta among its metabolites. To identify the metabolic enzymes responsible for TAMP formation, the in vitro activity was determined in human liver microsomes. The enzymatic activity depended on NADPH, and it was inhibited by ketoconazole. Furthermore, recombinant human cytochrome P450 (CYP) 3A4 and CYP3A5 displayed enzymatic activity in the assay. Therefore, CYP3A4/5 are the most important enzymes responsible for TAMP formation. [ABSTRACT FROM AUTHOR]

The pharmacokinetic and metabolite profiles of mizagliflozin, a novel selective sodium glucose co-transporter 1 inhibitor designed to act only in the intestine, were investigated in rats. Mizagliflozin administrated intravenously (0.3 mg/kg) and orally (3 mg/kg) declined with a short half-life (0.23 and 1.14 h, respectively). The absolute bioavailability was only 0.02%. Following intravenous administration of [14 C]mizagliflozin (0.3 mg/kg), radioactivity in plasma was also rapidly declined. Up to 24 h after oral administration of [14 C]mizagliflozin (1 mg/kg), radioactivity was recovered in the faeces (98.4%) and in the urine (0.8%). No remarkable accumulation of radioactivity in tissues was observed using tissue dissection technique and whole body autoradiography. Orally dosed [14 C]mizagliflozin was mostly metabolised to its aglycone, KP232, in the intestine. In the plasma, KP232 and its glucuronide were predominant. KP232 glucuronide was also prominent in the bile and was recovered as KP232 in the faeces possibly because of the deconjugation by gut microflora. Mizagliflozin was observed neither in the urine nor the faeces. These findings suggest that orally administered mizagliflozin is poorly absorbed, contributing to low systemic exposure; if absorbed, mizagliflozin is rapidly cleared from circulation. [ABSTRACT FROM AUTHOR]

1.The non-clinical pharmacokinetic profiles of rovatirelin, a novel thyrotropin-releasing hormone (TRH) analogue, were investigated in vivo and in vitro. 2.Rovatirelin orally administered to rats and dogs was rapidly absorbed and bioavailability was estimated to be 7.3 and 41.3%, respectively. The extent of plasma protein binding of rovatirelin in rats, dogs, and humans was low in all species (∼15%). The permeability of rovatirelin from blood to brain (permeability-surface area) ranged from 1.04 ± 0.14 to 1.29 ± 0.28 μL/min/g in rats, and rovatirelin was stable in rat plasma and brain homogenates. 3.The metabolite pattern was qualitatively similar in vitro and in vivo. In animals, rovatirelin aminopentanoic acid (rovatirelin-acid), rovatirelin aminopentanone (rovatirelin-ketone), rovatirelin pyrrolidine (4S)-hydroxy (rovatirelin-OH), (thiazoylalanyl)methylpyrrolidine (TAMP), 3-(4-thiazoyl)-L-alanine (TA), and unknown metabolites were observed. In human hepatocytes, TAMP was mainly formed and no unique human metabolite was observed. 4.The radioactivity from administered [14C]rovatirelin was predominantly excreted in faeces in rats and dogs, and almost all radioactivity was recovered 168 h after administration. Absorption, brain penetration, and stability of rovatirelin in the brain were greater than for taltirelin. 5.Thus, orally administered rovatirelin is a potentially improved treatment for spinocerebellar degeneration compared with taltirelin. [ABSTRACT FROM AUTHOR]

We evaluated the effects of probenecid, a potent organic anion transporter 1 (OAT1) and OAT3 inhibitor, on the pharmacokinetics and safety of ritobegron, a selective β3-adrenoceptor agonist, in healthy men. Twelve healthy men were administered a single oral dose of ritobegron (20 mg) alone or in combination with probenecid 2 hours before administration of ritobegron. In the combination sequence, additional doses of probenecid were administered 4 and 10 hours after the administration of ritobegron. Probenecid increased the Cmax of KUC-7322, an active form of ritobegron, and the AUC0-48 h by 1.39 and 2.93 times, respectively. Probenecid prolonged the t1/2 of KUC-7322 from 1.6 to 3.4 hours and decreased the renal clearance and cumulative fraction of KUC-7322 excreted in urine from 18.5 to 4.9 L/h and from 64.7% to 49.7%, respectively. Coadministration of probenecid did not influence adverse events, blood pressure, pulse rate, or heart rate relative to ritobegron alone. Although probenecid inhibited renal tubule secretion of KUC-7322 via OAT3 and increased KUC-7322 exposure, it did not influence adverse effects or vital signs. Therefore, clinically significant drug-drug interactions are unlikely to occur when probenecid is administered in combination with OAT3 inhibitors or substrates. [ABSTRACT FROM AUTHOR]

A rational design of phosphonium ionic liquid for ionicliquidcoated-lipase (IL1-PS)-catalyzed reaction has been investigated: veryrapid transesterification of secondary alcohols was accomplished whenIL1-PS was used as catalyst in tributyl((2-methoxyethoxy)methyl)phosphoniumbis(trifluoromethanesulfonyl)amide ([P444MEM][NTf2]) or N-ethyl-N-((2-methoxyethoxy)methyl)-N-methylethanaminium bis(trifluoromethanesulfonyl)amide([N221MEM][NTf2]) as solvent with excellentenantioselectivity. It was also revealed that ammonium ionic liquidinfluenced the lipase reactivity more strongly than phosphonium ionicliquids. Increased Kcatvalue was suggestedto be the most important factor at work in IL1-PS in these ionic liquidsolvents. The Kcatvalue of (S)-1-phenyethanol in [N444MEM][NTf2] was similarto that of i-Pr2O, and 1.6-fold accelerationwas achieved for (R)-1-phenylethanol. On the otherhand, the Kmvalue for (R)-isomer in [N444MEM][NTf2] was slightly largerthan the reaction in i-Pr2O, while itwas significantly reduced for (S)-isomer. These resultssuggest that solvent provides a certain impact on the reactivity ofthe enzyme protein of IL1-PS. [ABSTRACT FROM AUTHOR]

Rovatirelin is a newly synthetized thyrotropin-releasing hormone (TRH) analog. This study aimed to investigate the effect of rovatirelin on motor function using rolling mouse Nagoya (RMN), a mouse model of hereditary ataxia, and compare it with that of taltirelin, which is clinically used to treat spinocerebellar degeneration in Japan. We also examined the effect of rovatirelin on glucose metabolism in various brain regions of RMN using autoradiography (ARG). Rovatirelin (1, 3, 10, and 30 mg/kg) dose-dependently reduced the fall index in RMN, and its effect was more potent than that of taltirelin (3, 10, 30, and 100 mg/kg). No attenuation of the effect was observed by repeated daily administration for 2 weeks. Furthermore, the reduction in the fall index by rovatirelin persisted for 2 weeks after completing treatment. In the ARG study, rovatirelin induced a significantly elevated uptake of glucose in the prefrontal cortex, nucleus accumbens shell, nucleus accumbens core, striatum, anterior cingulate cortex, secondary motor area, pretectal area, ventral tegmental area, black pars compacta, locus coeruleus, nucleus cerebellaris middle nucleus, medial nucleus of the vestibular nerve, fourth/fifth lobule, and third lobule. Furthermore, rovatirelin increased cerebellar mRNA level of brain derived neurotrophic factor. These results suggest that rovatirelin activates the cerebellum and other parts of the central nervous system to improve motor function in spinocerebellar ataxia (SCA) model animals, and its action is more potent than that of taltirelin. Therefore, rovatirelin can be a potential alternative to the traditionally used therapeutics for SCA. [ABSTRACT FROM AUTHOR]

Objective　Polypharmacy in elderly individuals may cause reduced flow of saliva and xerostomia. A dry mouth can lead to poor oral function; however, there are no reports on the relationship between polypharmacy and subjective or objective oral dysfunction. The purpose of this study was to clarify the relationship between the number of prescribed medications and subjective and objective oral dysfunction.Methods　The subjects of this study were 215 community-dwelling, elderly individuals, aged 75 years or older, who visited the dental clinic in the Chubu region for a dental health examination from January to February 2019. A medical interview was conducted to assess three items that were related to subjective oral function and record four measurements related to objective oral function. In addition, information was collected on the diseases being treated and prescribed medications. A subject with a decrease in any of the three subjective oral function categories was considered to have subjective oral dysfunction. Objective oral dysfunction was analyzed with respect to two types of oral dysfunction: a decrease in all four objective oral functions and a decrease in two or more of the four objective oral functions. Logistic regression analysis was performed to examine the relationship between subjective and objective oral dysfunction after adjustment for sex, age group, inveterate disease, and the number of prescribed medications.Results　Individuals who had eight or more prescribed medications had lower subjective oral function than those with seven or fewer medications (odds ratio, 95% confidence interval: 2.3, 1.0-5.1; P<0.05). Individuals with eight or more medications had lower scores in all four objective oral functions than those with seven or fewer medications (4.4 : 1.5-12.6, P<0.01). A decrease in two or more of the four objective oral functions was related to 10 or more prescribed medications (4.3 : 1.2-16.2, P<0.05).　In addition, taking eight or more prescribed medications was associated with a decrease in either subjective oral function or all four objective oral functions (8.1 : 2.1-30.8, P<0.01). A decrease in either subjective oral function or two or more objective oral functions was related to taking 10 or more prescribed medications (4.9 : 1.6-15.6, P<0.01).Conclusion　In conclusion, more than eight prescribed pharmaceutical medications in the elderly is associated with subjective or objective oral dysfunction.

Acyl glucuronides (AGs) are reactive metabolites of carboxylic acid-containing drugs, which are associated with idiosyncratic toxicity (IDT) such as anaphylaxis, drug-induced liver injury, and so on. In this study, we developed a new in vitro approach for the quantitative assessment of the reactivity of AGs and their toxicity risk. Thirteen test drugs were incubated with human liver microsomes and uridine 5'-diphospho-glucuronic acid in the presence of cysteine (Cys) as a trapping agent. Both acylation and glycation Cys adducts formed from the AGs of the test drugs and were analyzed by ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry. Acylation Cys adduct formation can closely reflect the reactivity of AGs to predict their IDT risk. Subsequently, we performed a quantitative trapping assay using radiometric analysis, with [ 35 S]-labeled Cys ([ 35 S]Cys) as the trapping agent, and the results showed that the test drugs associated with IDT resulted in a high product formation of [ 35 S]Cys adducts. In conclusion, this approach can be used for the easy and quantitative evaluation of the reactivity of AGs without the need for authentic AG standards and to screen the potential IDT of new chemical entities during the early drug discovery phase.

The pharmacokinetic and metabolite profiles of mizagliflozin, a novel selective sodium glucose co-transporter 1 inhibitor designed to act only in the intestine, were investigated in rats. Mizagliflozin administrated intravenously (0.3 mg/kg) and orally (3 mg/kg) declined with a short half-life (0.23 and 1.14 h, respectively). The absolute bioavailability was only 0.02%. Following intravenous administration of [ 14  C]mizagliflozin (0.3 mg/kg), radioactivity in plasma was also rapidly declined. Up to 24 h after oral administration of [ 14  C]mizagliflozin (1 mg/kg), radioactivity was recovered in the faeces (98.4%) and in the urine (0.8%). No remarkable accumulation of radioactivity in tissues was observed using tissue dissection technique and whole body autoradiography. Orally dosed [ 14  C]mizagliflozin was mostly metabolised to its aglycone, KP232, in the intestine. In the plasma, KP232 and its glucuronide were predominant. KP232 glucuronide was also prominent in the bile and was recovered as KP232 in the faeces possibly because of the deconjugation by gut microflora. Mizagliflozin was observed neither in the urine nor the faeces. These findings suggest that orally administered mizagliflozin is poorly absorbed, contributing to low systemic exposure; if absorbed, mizagliflozin is rapidly cleared from circulation.

A 63-year-old Japanese woman with a 30-year history of systemic lupus erythematosus developed macrohematuria and massive proteinuria after seroconversion of myeloperoxidase anti-neutrophil cytoplasmic antibodies (MPO-ANCA). A renal biopsy indicated focal proliferative lupus nephritis (class III A/C) with a fibrous crescent formation. Methylprednisolone pulse therapy (500 mg, 3 successive days) was administered because of progressive proteinuria. Steroid therapy did not suppress the progressive proteinuria; therefore, tacrolimus was added as an alternative immunosuppressive therapy, resulting in the improvement of proteinuria and renal impairment. This case report suggests that MPO-ANCA might play a pathogenic role in the exacerbation of immune-complex-type lupus nephritis.

After a single oral dose of silodosin in male rats, male dogs and healthy human male volunteers, C(max) occurred within about 2 h, indicating rapid absorption. The elimination half-life was about 2 h in rat and dog, but 4.7 h (fasted) and 6.0 h (non-fasted) in humans. Absolute bioavailability values in rat, dog and human were about 9, 25 and 32%, respectively. In rat and dog, total blood clearance was almost equivalent to the hepatic blood flow, but that in human was low (20%), demonstrating a large species difference in hepatic clearance. In each species, the apparent volume of distribution exceeded the volume of total body water. After an oral dose of (14)C-silodosin to male rats, radioactivity was rapidly and widely distributed to most tissues. The highest concentrations outside the gastrointestinal tract were found in liver and kidney, with only low concentrations in brain tissues. The in vitro plasma protein binding of silodosin was about 80% in rat and dog, and 95.6% in humans, with alpha(1)-acid glycoprotein (AGP) contributing to the binding profile. Silodosin was found to be a dual substrate for CYP3A4 and p-glycoprotein. In human plasma, two major metabolites generated by UDP-glucuronosyltransferase (UGT; UGT2B7) and alcohol/aldehyde dehydrogenase (ADH/ALDH) were found, but no glucuronide conjugates were detected in rat or dog plasma. After a single oral dose of (14)C-silodosin in rat, dog and human, the urinary excretion of radioactivity was 15-34%, with that of unchanged silodosin being less than 4%. The radioactivity was predominantly excreted via the feces.

Objectives: The present study was undertaken to clarify the nature of sampling results with dental questionnaires between random sampling of subjects and of patients of dental clinics in the same city., Methods: The first group comprised 900 subjects selected using the stratified random sampling based on different age groups. The sampling rate was set at 6.46% of the population database and the approach was a mail survey with random sampling. The second group comprised 240 subjects who were patients of 12 dental clinics. The questionnaire had a list of questions about oral health conditions, daily oral habits, daily activities and common eating habits., Results: The response rates with the mailing method in the first group were 41.0% for male and 49.0% for female residents. The percentages who answered "Yes" to the questions, "Do you have gum swelling?" and "Have you ever received any instructions on tooth brushing from a professional?", were significantly (P < 0.05) lower than for patients from dental clinics., Conclusions: Dental patients had poor oral health habits and more oral diseases than residents, who visited dentists less frequently. It can be concluded that patients from dental clinics are inappropriate to use as samples to set a baseline for the general population in research evaluation of oral health.

Objectives: The physical and mental condition of elderly people changes every day and we hypothesized that this influences food intake and swallowing functions. The present study was undertaken to clarify relationships between daily living conditions and swallowing function., Methods: The subjects were users (105 males and 219 females) of 6 day-service centers. We performed a survey of IADL (Instrumental Activities of Daily Living), mobility, eating and swallowing behavior, and general health. In addition, we used RSST (Repetitive Saliva Swallowing Test) as a screen for functional dysphasia., Results: Women who had normal food ingestion and swallowing functions were capable of doing shopping, housework and taking care of money independently. Males and females who were capable of moving around from place to place had normal food ingestion and swallowing functions. With regard to daily eating habits and health condition, males and females who had normal food ingestion and swallowing functions were able to consume ordinary food, able to eat without any help, and often laugh., Conclusion: It was concluded that a normal swallowing condition in the elderly is related to laughing often, being independent in daily life, moving around and eating ordinary meals without any help.