Adeno-Associated Virus-Encapsulated Alginate Microspheres Loaded in Collagen Gel Carriers for Localized Gene Transfer.

This work reports localized in vivo gene transfer by biodegradation of the adeno-associated virus-encapsulating alginate microspheres (AAV-AMs) loaded in collagen gel carriers. AAV-AMs are centrifugally synthesized by ejecting a mixed pre-gel solution of alginate and AAV to CaCl2 solution to form an ionically cross-linked hydrogel microsphere immediately. The AAV-AMs are able to preserve the AAV without diffusing out even after spreading them on the cells, and the AAV is released and transfected by the degradation of the alginate microsphere. In addition, AAV-AMs can be stored by cryopreservation until use. By implanting this highly convenient AAV-encapsulated hydrogel, AAV-AMs can be loaded into collagen gel carriers to fix the position of the implanted AAV-AMs and achieve localized gene transfer in vivo. In vivo experiments show that the AAV-AMs loaded in collagen gel carriers are demonstrated to release the encapsulated AAV for gene transfer in the buttocks muscles of mice. While conventional injections caused gene transfer to the entire surrounding tissue, the biodegradation of AAV-AMs shows that gene transfer is achieved locally to the muscles. This means that the proposed AAV-loaded system is shown to be a superior method for selective gene transfer.

Fast-to-slow shift of muscle fiber-type composition by dietary apple polyphenols in rats: Impact of the low-dose supplementation.

Our previous studies demonstrated that an 8-week intake of 5% (w/w) apple polyphenol (APP) in the diet improves muscle endurance of young-adult rats. In order to identify a lower limit of the dietary contribution of APP to the effect, the experiments were designed for lower-dose supplementation (8-week feeding of 0.5% APP in AIN-93G diet) to 12-week-old male Sprague-Dawley rats. Results clearly showed that the 0.5% APP diet significantly up-regulates slower myosin-heavy-chain (MyHC) isoform ratios (IIx and IIa relative to total MyHC) and myoglobin expression in lower hind-limb muscles examined (P < 0.05). There was a trend to increased fatigue resistance detected from measurements of relative isometric plantar-flexion force torque generated by a stimulus train delivered to the tibial nerve (F(98, 1372) = 1.246, P = 0.0574). Importantly, there was no significant difference in the animal body-phenotypes or locomotor activity shown as total moving distance in light and dark periods. Therefore, the present study encourages the notion that even low APP-intake may increase the proportions of fatigue-resistant myofibers, and has promise as a strategy for modifying performance in human sports and improving function in age-related muscle atrophy.

Improvement of Endurance Based on Muscle Fiber-Type Composition by Treatment with Dietary Apple Polyphenols in Rats.

A recent study demonstrated a positive effect of apple polyphenol (APP) intake on muscle endurance of young-adult animals. While an enhancement of lipid metabolism may be responsible, in part, for the improvement, the contributing mechanisms still need clarification. Here we show that an 8-week intake of 5% (w/w) APP in the diet, up-regulates two features related to fiber type: the ratio of myosin heavy chain (MyHC) type IIx/IIb and myoglobin protein expression in plantaris muscle of 9-week-old male Fischer F344 rats compared to pair-fed controls (P < 0.05). Results were demonstrated by our SDS-PAGE system specialized for MyHC isoform separation and western blotting of whole muscles. Animal-growth profiles (food intake, body-weight gain, and internal-organ weights) did not differ between the control and 5% APP-fed animals (n = 9/group). Findings may account for the increase in fatigue resistance of lower hind limb muscles, as evidenced by a slower decline in the maximum isometric planter-flexion torque generated by a 100-s train of electrical stimulation of the tibial nerve. Additionally, the fatigue resistance was lower after 8 weeks of a 0.5% APP diet than after 5% APP, supporting an APP-dose dependency of the shift in fiber-type composition. Therefore, the present study highlights a promising contribution of dietary APP intake to increasing endurance based on fiber-type composition in rat muscle. Results may help in developing a novel strategy for application in animal sciences, and human sports and age-related health sciences.

Pharmacokinetics of mirabegron, a ß3-adrenoceptor agonist for treatment of overactive bladder, in healthy Japanese male subjects: results from single- and multiple-dose studies.

BACKGROUND: Mirabegron is a human ß3-adrenoceptor agonist for the treatment of overactive bladder. The pharmacokinetic profile of mirabegron has been extensively characterized in healthy Caucasian subjects. OBJECTIVE: The objective of this study was to evaluate the pharmacokinetics, dose-proportionality, and tolerability of mirabegron following single and multiple oral doses in healthy Japanese male subjects. The results were compared with those reported in non-Japanese (primarily Caucasian) subjects. METHODS: Two studies were conducted. In a single-blind, randomized, placebo-controlled, parallel-group, single- and multiple-ascending dose study (Study 1), mirabegron oral controlled absorption system (OCAS) tablets were administered at single doses of 50, 100, 200, 300, and 400 mg, with eight subjects (six active, two placebo) per dose group (Part I), and once daily for 7 days at 100 and 200 mg with 12 subjects (eight active, four placebo) per group (Part II). In an open-label, three-period, single-ascending dose study (Study 2), mirabegron OCAS was administered to 12 subjects at 25, 50, and 100 mg in an intra-subject dose-escalation design. Plasma and/or urine samples were collected up to 72 h after the first and last dose and analyzed for mirabegron. Pharmacokinetic parameters were determined using non-compartmental methods. Tolerability assessments included physical examinations, vital signs, 12-lead electrocardiogram, clinical laboratory tests (biochemistry, hematology, and urinalysis), and adverse event (AE) monitoring. RESULTS: Forty and 24 young male subjects completed Part I and II, respectively, of Study 1. Twelve young males completed Study 2. After single oral doses (25-400 mg), maximum plasma concentrations (C max) were reached at approximately 2.8-4.0 h postdose. Plasma exposure (C max and area under the plasma concentration-time curve) of mirabegron increased more than dose proportionally at single doses of 25-100 mg and approximately dose proportionally at high doses of 300 and 400 mg. A more than dose proportional increase in plasma exposure was noted in the body of the same individual. Mirabegron accumulated twofold upon once-daily dosing relative to single-dose data. Steady state was reached within 7 days. Mirabegron was generally well-tolerated at single doses up to 400 mg and multiple doses up to 200 mg. The AE with the highest incidence was increased pulse rate at 400 mg in Study 1. CONCLUSIONS: Mirabegron OCAS exhibits similar single- and multiple-dose pharmacokinetic characteristics and deviations from dose proportionality in healthy Japanese male subjects compared with those observed in non-Japanese (primarily Caucasian) subjects in previous studies.

Effect of dietary fat type on anxiety-like and depression-like behavior in mice.

Dietary fat plays an important role in higher brain functions. We aimed to assess the short and long term intake of three different types of dietary fat (soybean oil, lard, and fish oil) on anxiety-like and depression-like behavior in mice. For the short term intake assessment, a behavioral test battery for anxiety and depression was carried out for a 3-day feeding period. For the long term intake assessment, a behavioral test battery began after the 4-week feeding period. During the short term intake, the time spent in the open arms of the elevated plus-maze was the longest in the fish oil fed group, followed by the soybean oil and lard-fed groups. The elevated plus-maze is a common animal model to assess anxiety, in which an increased time spent in the open arms indicates an anxiolytic effect. The difference between the fish oil-fed group and lard-fed group was statistically significant (p < 0.01), but there was no significant difference between the soybean oil-fed group and the other two groups. Similar results were observed after a 4-week feeding period. On the other hand, there was no significant difference among the three groups in behavior tests to evaluate depression. Thus, the dietary fat types appeared to influence anxiety but not depression in mice, both in short term (3 days) and long term (4 weeks) feeding.

Estimation of the upper limit of the reference value of the QT interval in rest electrocardiograms in healthy young Japanese men using the bootstrap method.

BACKGROUND: A prolonged QT interval (QT) is associated with cardiac arrhythmia, and methods for identification of QT prolongation are required. METHODS: The relationship between RR and QT was investigated in resting electrocardiograms of 1276 healthy young Japanese men using the bootstrap method. RESULTS: The upper limit of QT (QT(upper limit)) was approximated well by the exponential equation: QT(upper limit) = 435 x RR(0.3409). We also defined an alternative upper limit of QTc(G upper limit) = 435 milliseconds, where QTc(G) was calculated by dividing QT by RR(0.3409). Thirty-two (2.51%) of the 1276 cases exceeded the criterion and were diagnosed as cases of QT prolongation. CONCLUSION: Using this limit, we propose a criterion to discriminate cases with prolonged QT intervals. The accuracy of the estimation of the mean and the upper limit of the reference value of the QT was good within the range of the RR interval from 0.812 to 1.263 s (heart rates from 48 to 74 beats per minute). Our approach for estimation of the exponent of RR differs from the well-known exponential equations proposed by Fridericia, but the exponent of RR in our equation is very close to that of Fridericia.