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Background: The present study was aimed to develop astaxanthin (AX)-loaded liposomes by the utilization of soybean phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) to improve the nutraceutical properties of AX. AX-loaded liposomes consisting of PC (PC/AX) and LPC (LPC/AX) were evaluated in terms of particle size distribution, morphology, release characteristics, pharmacokinetic behavior, and nephroprotective effects in a rat model of acute kidney injury., Results: PC/AX and LPC/AX had uniform size distributions with a mean particle size of 254 and 148 nm, respectively. Under pH 6.8 conditions, both liposomes exhibited improved dissolution behavior of AX compared with crystalline AX (cAX). In particular, LPC/AX showed a sevenfold higher release of AX than PC/AX. After the oral administration of LPC/AX (33.2 mg AX kg -1 ) to rats, there was a significant increase in systemic exposure to AX, as evidenced by a 15-fold higher AUC 0-24 h than PC/AX. However, the oral absorption of AX in the cAX group was negligible. Based on the results of histological analysis and measurement of plasma biomarkers, LPC/AX exhibited improved nephroprotective effects of AX in the rat model of kidney injury., Conclusion: From these observations, a strategic application of the LPC-based liposomal approach might be a promising option to improve the nutraceutical properties of AX. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

R-α-lipoic acid (RLA) and dihydrolipoic acid (DHLA), a reduced form of RLA, are potent endogenous antioxidants that can reduce oxidative damage. Despite their numerous nutraceutical potentials, clinical applications of RLA are still limited due to its poor solubility and stability problems. This study aimed to develop an RLA-loaded liposome (LIP/RLA) for the improvement of nutraceutical properties. LIP/RLA was developed by a typical solvent injection method. Uniform liposomes of LIP/RLA were observed by transmission electron microscopy, and the mean particle size was calculated to be ∼150 nm from the data of dynamic light scattering. LIP/RLA could prevent the degradation of RLA even under acidic conditions (pH 1.2) possibly due to the encapsulation of RLA into the liposomal structure. In the release test under pH6.8 with lipase, LIP/RLA showed relatively rapid release of RLA, possibly due to the lipolysis of phospholipids by lipase. After the oral administration of LIP/RLA (10 mg-RLA/kg, p.o. ) in rats, the systemic exposures of RLA and DHLA increased by 2.8- and 5.8-fold, respectively. In a rat model of acute hepatic injury induced by carbon tetrachloride (CCl 4 ) (0.7 mL-CCl 4 /kg, p.o. ), orally dosed LIP/RLA (3 mg-RLA/kg, p.o. ) resulted in 78.7% and 86.4% reductions of plasma alanine aminotransferase, and aspartate aminotransferase, respectively; however, RLA was found to be less effective possibly due to the poor oral absorption. The RLA-loaded liposomal system might be a promising carrier for poorly water-soluble materials with poor stability under acidic conditions, as well as RLA, to improve their oral absorption and nutraceutical properties.

Oarfish (Regalecus russelii Cuvier) are mesopelagic fish with little known about their life history. Oarfish live in deep water, making it difficult for researchers to collect specimens; thus, records of their parasitic helminths are limited. Two plerocercoids were found for the first time in an oarfish stranded on the coast of Akita Prefecture, Japan. These plerocercoids were identified as Clistobothrium sp. RR-1 using morphological and molecular analyses. It was revealed that oarfish represent one of the intermediate hosts of the genus Clistobothrium, and large sharks are the definitive hosts for these parasites.

Using echolocation, bats receive acoustic information on their surroundings, which is assumed to help them sophisticatedly navigate complex environments. In this study, to understand spatial learning and acoustic sensing in bats, we investigated how flight and echolocation control changed in Rhinolophus ferrumequinum nippon as they learnt about their surroundings in an obstacle course that they flew through repeatedly. In these experiments, two testing environments (acoustically permeable and acoustically reflective) were prepared using chains and acrylic boards as obstacles to evaluate the interactive effects of spatial learning and flight environments. We found that bats reduced the meandering width of their flights and pulse emissions, and also seemed to reduce their shifts in pulse direction as they learnt more about their environments in both conditions. Throughout all our experiments, the bats with slower flight speeds tended to emit more pulses, which suggests that the number of pulse emissions reflects the echolocation tactics of each bat. The maximum flight speed was especially increased in the acoustically permeable condition, with frequent emissions of multiple pulses (≧triplets) in the early stages of flight, suggesting that bats adjust their flight plan based on how much of their surroundings they are able to sense in advance.

This study aimed to evaluate the effect of liposomes loaded with diclofenac, a potent cyclooxygenase (COX)-1 and COX-2 inhibitor, on laser-induced choroidal neovascularization (CNV) in mice and non-human primates (common marmosets). CNV was induced by laser irradiation on the unilateral or bilateral eye of each mouse or common marmoset, respectively, under anesthesia. The CNV was visualized using fluorescence labeling with intravenous injection of fluoresceinconjugated dextran (molecular weight = 2,000 kDa), and quantified in the retinal pigment epithelia (RPE)-choroidal flatmounts. Diclofenac-loaded liposome or diclofenac ophthalmic solution was instillated to the eye surface daily for 14 days and 21 days in mice and common marmosets, respectively. In the mouse CNV model, 0.1% diclofenac-loaded liposome eye drops administered four times a day (q.i.d.) significantly reduced CNV formation in the RPE-choroidal flatmounts compared with those in empty liposome eye drops. Diclofenac-loaded liposome (0.1%) eye drops, administered once a day (s.i.d.), twice a day (b.i.d.), and three times a day (t.i.d.), also reduced CNV formation in a frequency-dependent manner. Furthermore, diclofenac-loaded liposome (0.03% and 0.1%) eye drops administered t.i.d. reduced CNV formation in a dose-dependent manner, significantly so at 0.1%. In the common marmoset CNV model, late hyperfluorescence and leakage by fluorescein angiograms was observed within or beyond the lesion borders at 17 days after laser irradiation, and diclofenac-loaded liposome eye drops (0.1% t.i.d.) tended to attenuate the late hyperfluorescence and leakage. Diclofenac-loaded liposomes had significantly reduced CNV formation in the RPE- choroidal flatmounts at 21 days after laser irradiation. In conclusion, diclofenac-loaded liposome eye drops enhance penetration to the RPE-choroid, and reduce the CNV formation. These results suggest that a drug-loaded liposome is a useful tool for drug delivery into the posterior segment of the eye., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)