Blood-to-muscle distribution and urinary excretion of higenamine in rats.

Higenamine is a ß2 -agonist that has been prohibited in sports by the World Anti-Doping Agency. Higenamine could potentially promote anabolism and lipolysis; however, its crucial pharmacokinetics data, particularly muscle distribution, remain unavailable. The present study aims to investigate the blood-to-muscle distribution as well as the urinary excretion of higenamine in laboratory rats. In the first experiment, the microdialysis technique was employed to continuously measure free, protein-unbound concentrations in blood and muscle for 90 min (sampling at a 5-min interval) after rats received IV infusion of higenamine. The mean half-lives of higenamine in blood and muscle were 17.9 and 19.0 min, respectively. The blood-to-muscle distribution ratio (AUCmuscle /AUCblood ) of higenamine was estimated to be 22%. In the second experiment, rats were orally administered with a single-dose higenamine, and their urine samples were profiled at a 12-h interval for up to 48 h. Results showed only a small portion of total consumption (1.44%, ranging 0.71%-2.50%) was excreted in the urine. Among these time points, about 43% cumulative amount of higenamine was eliminated within the first 12 h. Our data suggested that one-quarter of the unbound higenamine rapidly penetrates from the vessels into muscle, distributes to the interstitial fluid, then eliminates from the rat in a short span of time. The muscle tissue is likely to have a low binding affinity for higenamine, and renal excretion plays a minor role in its elimination. Together, our findings provide valuable pharmacokinetics data that may gain deeper insights into higenamine's role in skeletal muscle functions.

Self-Nanoemulsifying Drug Delivery Systems for Enhancing Solubility, Permeability, and Bioavailability of Sesamin.

Sesamin (SSM) is a water-insoluble compound that is easily eliminated by liver metabolism. To improve the solubility and bioavailability of SSM, this study developed and characterized a self-nanoemulsifying drug delivery system (SNEDDS) for the oral delivery of SSM and conducted pharmacokinetic assessments. Oil and surfactant materials suitable for SNEDDS preparation were selected on the basis of their saturation solubility at 37 ± 0.5 °C. The mixing ratios of excipients were determined on the basis of their dispersibility, transmittance (%), droplet sizes, and polydispersity index. An SNEDDS (F10) formulation comprising glyceryl trioctanoate, polyoxyethylene castor oil, and Tween 20 at a ratio of 10:10:80 (w/w/w) was the optimal formulation. This formulation maintained over 90% of its contents in different storage environments for 12 weeks. After the self-emulsification of SNEDDS, the SSM dispersed droplet size was 66.4 ± 31.4 nm, intestinal permeability increased by more than three-fold, relative bioavailability increased by approximately 12.9-fold, and absolute bioavailability increased from 0.3% to 4.4%. Accordingly, the developed SNEDDS formulation can preserve SSM's solubility, permeability, and bioavailability. Therefore, this SNEDDS formulation has great potential for the oral administration of SSM, which can enhance its pharmacological application value.

Chinese herbal decoction (Danggui Buxue Tang) supplementation augments physical performance and facilitates physiological adaptations in swimming rats.

Context: Danggui Buxue Tang (DBT), one of the popular Danggui (DG) decoctions, has traditionally been used to nourish 'qi' (vital energy) and enrich 'blood' (body circulation). DBT may possess performance-enhancing effects.Objective: This work determines whether DBT can improve physical capacity and alter energy expenditure under exercise training.Materials and methods: Forty male Wistar rats were assigned to four groups: sedentary (SE), exercise training (ET), ET supplemented with 0.3 g/kg rat/d DG extract, and ET supplemented with 1.8 g/kg rat/d DBT extract. The supplementations were administered via oral gavage. During the 21-day treatment period, the exercised groups were subjected to a protocol of swimming training with a gradually increased load. Physical performance evaluation was assessed using the forelimb grip strength test and an exhaustive swimming test. Muscle glycogen contents and exercise-related biochemical parameters were analysed.Results: Both herbal supplementations remarkably increased the grip strength (DG by 49.7% and DBT by 85.7%) and prolonged the swimming time (DG by 48.4% and DBT by 72.7%) compared with SE. DBT spared a certain amount of glycogen in the muscle cells under exercise training. Regarding the regulation of fuel usage, DBT had a positive impact alongside ET on promoting aerobic glycolysis via significantly decreasing serum lactate by 31.6% and lactic dehydrogenase levels by 61.8%.Conclusions: This study found that DBT could be considered a promising sports ergogenic aid for athletic population or fitness enthusiasts. Future work focussing on isolating the bioactive components that truly provide the ergogenic effects would be of interest.

Oral Bioavailability Enhancement and Anti-Fatigue Assessment of the Andrographolide Loaded Solid Dispersion.

Andrographolide (AG), a major diterpene lactone isolated from Andrographis paniculata (Burm. f.) Nees (Acanthaceae), possesses a wide spectrum of biological activities. However, its poor water solubility and low bioavailability limit its clinical application. Therefore, this study aimed to develop a solid dispersion (SD) formulation to increase the aqueous solubility and dissolution rate of AG. Different drug-polymer ratios were used to prepare various SDs. The optimized formulation was characterized for differential scanning calorimetry, Fourier transform infrared spectroscopy, and powder X-ray diffraction. The analysis indicated that the optimized SD enhanced AG solubility and dissolution rates by changing AG crystallinity to an amorphous state. The dissolution behaviors of the optimum SD composed of an AG-polyvinylpyrrolidone K30-Kolliphor EL ratio of 1:7:1 (w/w/w) resulted in the highest accumulated dissolution (approximately 80%). Pharmacokinetic studies revealed that Cmax/dose and the AUC/dose increased by 3.7-fold and 3.0-fold, respectively, compared with AG suspension. Furthermore, pretreatment using the optimized AG-SD significantly increased the swimming time to exhaustion by 1.7-fold and decreased the plasma ammonia level by 71.5%, compared with the vehicle group. In conclusion, the optimized AG-SD formulation appeared to effectively improve its dissolution rate and oral bioavailability. Moreover, the optimized AG-SD provides a promising treatment against physical fatigue.

Potential Risk of Higenamine Misuse in Sports: Evaluation of Lotus Plumule Extract Products and a Human Study.

Since 2017, higenamine has been added to the World Anti-Doping Agency (WADA) prohibited list as a ß2-agonist prohibited at all times for sportspersons. According to WADA's report, positive cases of higenamine misuse have been increasing yearly. However, higenamine occurs naturally in the Chinese herb lotus plumule-the green embryo of lotus (Nelumbo nucifera Gaertn) seeds-commercially available as concentrated powder on the Asian market. This study evaluated the major phytochemical components of lotus plumule products using an appropriate extraction method, followed by a human study in which the products were orally administered in multiple doses to investigate the risk of doping violations. Comparing various extraction methods revealed that optimized microwave-assisted extraction exhibited the highest extraction efficiency (extraction time, 26 min; power, 1046 W; and temperature, 120 °C). Subsequently, the alkaloids in lotus plumule products were quantitatively confirmed and compared. Human study participants (n = 6) consumed 0.8 g of lotus plumule (equivalent to 679.6 µg of higenamine) three times daily for three consecutive days. All participants' urinary higenamine concentrations exceeded the WADA reporting cut-off of 10.0 ng/mL. Accordingly, lotus plumule consumption may engender adverse analytical findings regarding higenamine. Athletes should avoid consuming lotus plumule-containing products during in- and out-of-competition periods.

Repressed Exercise-Induced Hepcidin Levels after Danggui Buxue Tang Supplementation in Male Recreational Runners.

This study was to investigate the protective and recovery effects of Danggui Buxue Tang (DBT) supplementation on exercise performance, hepcidin, iron status, and other related biochemical parameters after being challenged by a single bout of intense aerobic exercise. A total of 36 recreationally active males were pair-matched and randomly assigned to receive DBT or a placebo for 11 days, while using clusters based on their aerobic capacities. On the eighth day of the supplementation, the participants performed a 13-km run with maximal effort. Blood and urine samples were collected and analysed before treatment (Pre-Tre) and immediately after (Post-Ex), 24 h after (24-h Rec), and 72 h after (72-h Rec) the run. DBT supplementation dramatically shortened the finish times by 14.0% (12.3 min) when compared with that in the placebo group. Significant group × time effects were observed in serum hepcidin and iron levels. DBT supplementation repressed hepcidin levels at Post-Ex and 24-h Rec, thereby causing a significant increase in iron levels by 63.3% and 31.4% at Post-Ex and 72-h Rec, respectively. However, DBT supplementation had no significant anti-inflammatory or haemolysis-preventative effects. Short-term DBT supplementation shortened the running time and repressed exercise-induced hepcidin levels, thereby boosting iron levels and accelerating iron homeostasis during recovery.

Nanoemulsion as a strategy for improving the oral bioavailability and anti-inflammatory activity of andrographolide.

BACKGROUND: Andrographolide (AG), a compound with low water solubility, possesses various pharmacological activities, particularly anti-inflammatory activity. However, its low oral bioavailability is a major obstacle to its potential use. This study developed and optimized an AG-loaded nanoemulsion (AG-NE) formulation to improve AG oral bioavailability and its protective effects against inflammatory bowel disease. METHODS: A high-pressure homogenization technique was used to prepare the AG-NE and solubility, viscosity, and droplet size tests were conducted to develop the optimized AG-NE composed of α-tocopherol, ethanol, Cremophor EL, and water. The permeability was assessed using everted rat gut sac method and in vivo absorption and anti-inflammatory effect in rats was also evaluated. The plasma concentration of AG was determined using our validated high performance liquid chromatography method, which was used to generate a linear calibration curve over the concentration range of 0.1-25 µg/mL in rat plasma (R2>0.999). RESULTS: The optimized AG-NE had a droplet size of 122±11 nm confirmed using transmission electron microscopy and a viscosity of 28 centipoise (cps). It was stable at 4 and 25°C for 90 days. An ex vitro intestinal permeability study indicated that the jejunum was the optimal site for AG absorption from the optimized AG-NE, which was 8.21 and 1.40 times higher than that from an AG suspension and AG ethanol solution, respectively. The pharmacokinetic results indicate that the absorption of AG from AG-NE was significantly enhanced in comparison with that from the AG suspension, with a relative bioavailability of 594.3%. Moreover, the ulcer index and histological damage score of mice with indomethacin-induced intestinal lesions were significantly reduced by AG-NE pretreatment. CONCLUSION: We conclude that the developed AG-NE not only enhanced the oral bioavailability of AG in this study but may also prove to be an effective formulation of AG for preventing gastrointestinal inflammatory disorders.

Microwave-Assisted Extraction of Cannabinoids in Hemp Nut Using Response Surface Methodology: Optimization and Comparative Study.

Hemp nut is commonly incorporated into several food preparations; however, most countries set regulations for hemp products according to their cannabinoid content. In this study, we have developed an efficient microwave-assisted extraction (MAE) method for cannabinoids (i.e., Δ9-tetrahydrocannabinol, cannabidiol, and cannabinol) in hemp nut. Optimization of the MAE procedure was conducted through single factor experiments and response surface methodology (RSM). A comparative study was also conducted to determine the differences in the extraction yields and morphology of hemp nut between MAE and reference extraction methods, namely heat reflux extraction (HRE), Soxhlet extraction (SE), supercritical fluid extraction (SFE), and ultrasound-assisted extraction (UAE). Among the independent variables in RSM, the temperature was the most significant parameter. The optimal conditions of MAE were as follows: extraction solvent of methanol, microwave power of 375 W, temperature of 109 °C, and extraction time of 30 min. Compared with reference extraction methods, MAE achieved the highest extraction yields of total cannabinoids in hemp nut (6.09 µg/g for MAE; 4.15 µg/g for HRE; 5.81 µg/g for SE; 3.61 µg/g for SFE; 3.73 µg/g for UAE) with the least solvent consumption and shortest time. Morphological observations showed that substantial cell rupturing occurred in the microstructure of hemp nut after MAE, indicating enhanced dissolution of the target compounds during the extraction process. The MAE method is thus a rapid, economic, and environmentally friendly extraction method that is both effective and practical for industrial applications.

Self-Nanoemulsifying Drug Delivery System for Resveratrol: Enhanced Oral Bioavailability and Reduced Physical Fatigue in Rats.

Resveratrol (RES), a natural polyphenolic compound, exerts anti-fatigue activity, but its administration is complicated by its low water solubility. To improve RES bioavailability, this study developed a self-nanoemulsifying drug delivery system (SNEDDS) for RES and evaluated its anti-fatigue activity and rat exercise performance by measuring fatigue-related parameters, namely lactate, ammonia, plasma creatinine phosphokinase, and glucose levels and the swimming time to exhaustion. Through solubility and emulsification testing, the optimized SNEDDS composed of Capryol 90, Cremophor EL, and Tween 20 was developed; the average particle size in this formulation, which had favorable self-emulsification ability, was approximately 41.3 ± 4.1 nm. Pharmacokinetic studies revealed that the oral bioavailability of the optimized RES-SNEDDS increased by 3.2-fold compared with that of the unformulated RES-solution. Pretreatment using the RES-SNEDDS before exercise accelerated the recovery of lactate after exercise; compared with the vehicle group, the plasma ammonia level in the RES-SNEDDS group significantly decreased by 65.4%, whereas the glucose level significantly increased by approximately 1.8-fold. Moreover, the swimming time to exhaustion increased by 2.1- and 1.8-fold, respectively, compared with the vehicle and RES-solution pretreatment groups. Therefore, the developed RES-SNEDDS not only enhances the oral bioavailability of RES but may also exert anti-fatigue pharmacological effect.

Bioanalytical Method Development Using Liquid Chromatography with Amperometric Detection for the Pharmacokinetic Evaluation of Forsythiaside in Rats.

An analytical method entailing high-performance liquid chromatography coupled with electrochemical detection was developed for determining forsythiaside (FTS) in rat plasma. Rat plasma samples were prepared through efficient trichloroacetic acid deproteination. FTS and the internal standard were chromatographically separated on a reversed-phase core-shell silica C18 column (100 mm × 2.1 mm, i.d. 2.6 µm), with a mobile phase consisting of an acetonitrile-0.05-M phosphate solution (11.8:88.2, v/v), at a flow rate of 400 µL/min. The calibration curve, with r² > 0.999, was linear in the 20-1000 ng/mL range. The intra- and interday precision were less than 9.0%, and the accuracy ranged from 94.5% to 106.5% for FTS. The results indicated that the newly developed HPLC-EC method is more sensitive than previous reported methods using UV detection, and this new analytical method is applied successfully for the pharmacokinetic study of FTS. The hydrogel delivery system can efficiently improve bioavailability and mean residual time for FTS, as evidenced by the 2.5- and 6.3-fold increase of the area under the curve and the extension of the half-life, respectively.