Changes in Muscle Shear Modulus and Urinary Titin N-Terminal Fragment after Eccentric Exercise.

This study aimed to investigate the relationship between the muscle shear modulus of the biceps brachii, urinary titin N-terminal fragment (UTF), and other damage markers after eccentric exercise. Seventeen healthy males performed five sets of ten eccentric exercises with dumbbells weighing 50% of the maximum voluntary contraction (MVC) at the elbow joint. Muscle shear modulus with range of interest set to only biceps brachii muscle measured by ultrasound shear wave elastography, UTF, MVC, range of motion (ROM), and soreness (SOR) were recorded before, immediately after, and 1, 24, 48, 72, 96, and 168 h after eccentric exercise. Each marker changed in a time course pattern, as found in previous studies. The peak shear modulus showed a moderate negative correlation with peak MVC (r = -0.531, P < 0.05) and a strong positive correlation with peak UTF (r = 0.707, P < 0.01). Our study results revealed a significant relationship between muscle strength, shear modulus measured by ultrasound SWE, and titin measured by UTF, as a non-invasive damage marker after eccentric exercise to track changes in EIMD.

Pre-cooling with ingesting a high-carbohydrate ice slurry on thermoregulatory responses and subcutaneous interstitial fluid glucose during heat exposure.

The purpose of this study was to compare the effects of ingesting ice slurries with two different carbohydrate contents on body temperatures and the subcutaneous interstitial fluid glucose level during heat exposure. Seven physically active men underwent one of three interventions: the ingestion of 7.5 g/kg of a control beverage (CON: 26°C), a normal-carbohydrate ice slurry (NCIS: -1°C), or a high-carbohydrate ice slurry (HCIS: -5°C). The participants were monitored for a 120-min period that included 10 min of rest, 25 min of exposure to the experimental cooling intervention (during which the beverage was ingested), and 85 min of seated rest in a climate chamber (36°C, 50% relative humidity). The rectal temperature in the HCIS and NCIS trials was lower than that in the CON trial from 40 to 75 min. The infrared tympanic temperature was also lower in the HCIS and NCIS trials than in the CON trial from 20 to 50 min, whereas the deep thigh or mean skin temperatures were not significantly different among the three groups. From 90 to 120 min, the subcutaneous interstitial fluid glucose level in the NCIS trial was lower than that at 65 min; however, reductions were not seen in the HCIS and CON trials. These findings suggest that both HCIS ingestion and conventional NCIS ingestion were effective cooling strategies for reducing thermal strain, while HCIS ingestion may also enable a higher subcutaneous interstitial fluid glucose level to be maintained, ensuring an adequate supply of required muscle substrates.

Ice slurry ingestion improves physical performance during high-intensity intermittent exercise in a hot environment.

Ice slurry ingestion enhances exercise performance by lowering the core body temperature. However, an operational issue related to this ingestion is the requirement for a high intake of 7.5 g·kg-1 to produce the desired effects. We investigated the effects of the intake of low amounts of ice slurry at -2°C on the tympanic temperature and exercise performance during repeated high-intensity intermittent exercises in a hot environment. This study was a randomized, crossover study, with a 6-day washout period. Twelve university rugby union players performed two 30-min sessions of high-intensity intermittent exercises separated by a 15-min half-time break on a cycle ergometer in a hot environment (28.8°C ± 0.1°C, 49.5% ± 0.6% relative humidity). The participants ingested 450 g of -2°C-ice slurry (ICE), or a 30°C-beverage (CON) having the same composition as ICE, or 30°C-water (WAT) during the half-time break. The tympanic temperature and skin temperature were measured as the physiological data, and the peak power and mean power as the exercise performance data. The tympanic temperature at the half-time break and beginning of the 2nd session was significantly lower in the ICE group as compared with the CON and WAT groups. The skin temperature at the half-time break was significantly lower in the ICE group as compared with the WAT group. While the peak power and mean power during the 2nd session were significantly greater in the ICE group as compared with the CON and WAT groups. Our findings suggest that even the intake of lower amounts, as compared with those used in previous studies, of low-temperature ice slurry can reduce the body temperature and improve the peak power. These results suggest that intake of low-temperature ice slurry as a strategy for internal body cooling is useful for improving endurance exercise performance in hot environments.

Reduction of Excessive Visceral Fat and Safety with 52-Week Administration of Lipase Inhibitor Orlistat in Japanese: Long-Term Clinical Study.

INTRODUCTION: Orlistat is an inhibitor of pancreatic lipase and is used as an anti-obesity drug in many countries. However, there are no data available regarding the effects of orlistat on visceral fat (VF) accumulation in Japanese individuals. Therefore, this study aimed to analyze the efficacy and safety of 52 weeks of orlistat administration in Japanese individuals. METHODS: Orlistat 60 mg was administered orally three times daily for 52 weeks to Japanese participants with excessive VF accumulation and without dyslipidemia, diabetes mellitus, and hypertension (metabolic diseases). Participants were also counseled to improve their diet and to maintain exercise habits. We defined excessive VF accumulation as a waist circumference (WC) of ≥ 85 cm for males and ≥ 90 cm for females, which corresponds to a VF area of 100 cm2. Adverse reactions, clinical laboratory tests, VF, WC, body weight (BW), etc., were monitored throughout the study period. RESULTS: VF, WC, and BW were significantly reduced at week 52 from baseline; the mean ± standard error rate of change was - 21.52% ± 1.89%, - 4.89% ± 0.45%, and - 5.36% ± 0.56%, respectively, and continued to reduce throughout the 52 weeks; these significantly reduced at whole term compared with baseline. Most adverse reactions were defecation-related symptoms such as oily spotting and flatus with discharge (flatus with small amounts of stool or oil) due to the pharmacologic effects of the lipase inhibitor. These symptoms were mostly mild, reversible, and recognizable by the participants; none were serious or severe. No participants discontinued by medical judgment about adverse reactions, and the drug could be administered continuously. CONCLUSION: VF, WC, and BW were reduced from week 4 to week 52, indicating the effect of long-term orlistat administration. Moreover, it was well tolerated with an acceptable safety profile. Long-term administration of orlistat may be efficacious in reducing VF accumulation with safety when used in combination with diet and exercise. TRIAL REGISTRATION: This study is registered with the Japan Pharmaceutical Information Center (identifier: JapicCTI-184004). FUNDING: Funding for this study was provided by Taisho Pharmaceutical Co., Ltd.

Efficacy and Safety of Lipase Inhibitor Orlistat in Japanese with Excessive Visceral Fat Accumulation: 24-Week, Double-Blind, Randomized, Placebo-Controlled Study.

INTRODUCTION: Orlistat is an inhibitor of pancreatic lipase and is used as an anti-obesity drug in many countries. However, there are no data available regarding the effects of orlistat on visceral fat accumulation in Japanese subjects. Therefore, this comparative, placebo-controlled, double-blind, randomized study aimed to evaluate the efficacy and safety of orlistat in Japanese participants with excessive visceral fat accumulation and without dyslipidemia, diabetes mellitus, and hypertension ("metabolic diseases"). METHODS: The study population included Japanese participants with excessive visceral fat accumulation (waist circumference ≥ 85 cm in males and ≥ 90 cm in females, which corresponds to a visceral fat area of 100 cm2) and without metabolic diseases. Following a 12-week observation term, participants were randomized to the orlistat 60 mg group (n = 100) or placebo group (n = 100). Both drugs were administered orally three times daily for 24 weeks. Participants were also counseled to improve their diet and to maintain exercise throughout the study. Visceral fat area, subcutaneous fat area, waist circumference, body weight, body mass index, adverse reactions, laboratory tests, and blood pressure were regularly assessed. RESULTS: Visceral fat area, waist circumference, and body weight were significantly reduced in the orlistat group (mean ± standard error, - 13.50 ± 1.52%, - 2.51 ± 0.25%, and - 2.79 ± 0.30%, respectively) compared to the placebo group (- 5.45 ± 1.50%, - 1.55 ± 0.26%, and - 1.22 ± 0.28%, respectively) at the last assessment. The main adverse reactions were defecation-related symptoms including oily spotting and flatus with discharge, resulting from the pharmacological effects of orlistat. Most adverse reactions were mild, and none were serious or severe. CONCLUSION: Orlistat administration reduced visceral fat area, waist circumference, and body weight in Japanese participants with excessive visceral fat and without metabolic diseases. In addition, safety was confirmed with a tolerable profile. Orlistat may be useful to reduce excessive visceral fat accumulation when used in combination with diet and exercise. TRIAL REGISTRATION: Japan Pharmaceutical Information Center identifier, JapicCTI-184005. FUNDING: Taisho Pharmaceutical Co., Ltd.

Determination of the Optimal Concentration of Valproic Acid in Patients with Epilepsy: A Population Pharmacokinetic-Pharmacodynamic Analysis.

Valproic acid (VPA) is one of the most widely prescribed antiepileptic drugs for the treatment of epileptic seizures. Although it is well known that the doses of VPA and its plasma concentrations are highly correlated, the plasma concentrations do not correlate well with the therapeutic effects of the VPA. In this study, we developed a population-based pharmacokinetic (PK)-pharmacodynamic (PD) model to determine the optimal concentration of VPA according to the clinical characteristics of each patient. This retrospective study included 77 VPA-treated Japanese patients with epilepsy. A nonlinear mixed-effects model best represented the relationship between the trough concentrations of VPA at steady-state and an over 50% reduction in seizure frequency. The model was fitted using a logistic regression model, in which the logit function of the probability was a linear function of the predicted trough concentration of VPA. The model showed that the age, seizure locus, the sodium channel neuronal type I alpha subunit rs3812718 polymorphism and co-administration of carbamazepine, clonazepam, phenytoin or topiramate were associated with an over 50% reduction in the seizure frequency. We plotted the receiver operating characteristic (ROC) curve for the logit(Pr) value of the model and the presence or absence of a more than 50% reduction in seizure frequency, and the areas under the curves with the 95% confidence interval from the ROC curve were 0.823 with 0.793-0.853. A logit(Pr) value of 0.1 was considered the optimal cut-off point (sensitivity = 71.8% and specificity = 80.4%), and we calculated the optimal trough concentration of VPA for each patient. Such parameters may be useful to determine the recommended therapeutic concentration of VPA for each patient, and the procedure may contribute to the further development of personalized pharmacological therapy for epilepsy.

Effects of CYP2C19 and P450 oxidoreductase polymorphisms on the population pharmacokinetics of clobazam and N-desmethylclobazam in japanese patients with epilepsy.

BACKGROUND: Clobazam (CLB) is a 1,5-benzodiazepine with antiepileptic properties. More than 70% of administered CLB is dealkylated to yield N-desmethylclobazam (N-CLB), a pharmacologically active metabolite, by cytochrome P450 (CYP) 3A4 and CYP2C19. The subsequent inactivation of N-CLB is primarily catalyzed by CYP2C19. Meanwhile, P450 oxidoreductase (POR) is the obligatory electron donor to all microsomal CYP enzymes. The aim of this study was to evaluate the impact of the CYP2C19 and POR genotypes on the pharmacokinetic parameters of CLB and N-CLB. METHODS: This retrospective study included 85 Japanese patients with epilepsy who were treated with CLB. CYP2C19*2, *3, and P450 oxidoreductase (POR) *28 (rs1057868C>T) polymorphisms were evaluated. A total of 128 steady-state concentrations for both CLB and N-CLB were collected from the patients. A nonlinear mixed-effects model identified the pharmacokinetics of CLB and N-CLB; the covariates included CYP2C19 and POR genotypes, weight, gender, daily CLB dose, and coadministered antiepileptic drugs. RESULTS: Among the 85 patients, the allele frequencies of CYP2C19*2, CYP2C19*3, and POR*28 were 27.6%, 12.9%, and 41.2%, respectively. A one-compartment model with first-order absorption and/or elimination showed that the clearance of CLB and N-CLB was significantly lower by 18.1% and 84.9%, respectively, in the CYP2C19 poor metabolizers compared with the homozygous extensive metabolizers. The CLB clearance was 44% higher in subjects homozygous for the POR*28 T allele than in those homozygous for the POR*28 C allele, although the genotypes did not affect the N-CLB clearance. The concomitant use of phenobarbital, phenytoin, and zonisamide significantly affected the CLB clearance, whereas that of carbamazepine, phenytoin, and valproic acid affected the N-CLB clearance. The weight also significantly influenced the CLB clearance and volume of distribution of both CLB and N-CLB. CONCLUSIONS: Our results showed that the CYP2C19 and/or POR genotypes have an impact on the CLB and/or N-CLB clearance. These results suggest that determining the CYP2C19 and/or POR genotypes is helpful for obtaining appropriate serum CLB and N-CLB concentrations and preventing an overdose when starting CLB therapy.

A herbal-drug interaction study of keishi-bukuryo-gan, a traditional herbal preparation used for menopausal symptoms, in healthy female volunteers.

OBJECTIVES: Many patients use herbal medicines to relieve menopausal symptoms. Keishi-bukuryo-gan contains five herbal components, and has been used for treating hypermenorrhoea, dysmenorrhoea and menopausal symptoms in Asian countries. In this study, we investigated the potential herb-drug interactions of keishi-bukuryo-gan in healthy female subjects. METHODS: Thirty-one healthy females (20-27 years) were studied to evaluate their baseline activity of cytochrome P450 (CYP) 1A2, CYP2D6, CYP3A, xanthine oxidase (XO) and N-acetyltransferase 2 (NAT2) based on the urinary metabolic indices of an 8-h urine sample collected after a 150-mg dose of caffeine and a 30-mg dose of dextromethorphan, and also the urinary excretion ratio of 6ß-hydroxycortisol to cortisol. Thereafter, the subjects received 3.75g of keishi-bukuryo-gan twice daily for seven days, and underwent the same tests on post-dose day 7. KEY FINDINGS: The geometric mean phenotypic index for CYP1A2 significantly decreased by 16% on day 7 compared with the baseline (P=0.026). Keishi-bukuryo-gan did not alter the indices for CYP2D6, CYP3A, XO and NAT2. CONCLUSIONS: Keishi-bukuryo-gan may inhibit the activity of CYP1A2, which is predominantly involved in oestrogen metabolism. However, TJ-25 is unlikely to participate in herb-drug interactions involving medications predominantly metabolized by CYP2D6, CYP3A, XO and NAT2. K