Possibility of nanostructured lipid carriers encapsulating astaxanthin from Haematococcus pluvialis to alleviate skin injury in radiotherapy.

PURPOSE: The study aimed to protect patients' skin against ionizing irradiation during radiotherapy by using astaxanthin-encapsulated nanostructured lipid carriers (NLC-ATX). MATERIALS AND METHODS: NLC-ATX was prepared by a combined method of hot homogenization and sonication. Cytotoxicity of NLC-ATX was evaluated by MTT colorimetric assay. The in vitro radioprotection of NLC-ATX for human fibroblast (HF) cells was investigated based on the level of ROS (reactive oxygen species), DNA damage, and cell death caused by X-irradiation. In addition, the in vivo radioprotection was evaluated based on the appearance and histological structure of the irradiated skin. RESULTS: NLC-ATX was successfully prepared, with a mean particle size, zeta potential, and encapsulation efficiency of 114.4 nm, -34.1 mV, and 85.67%, respectively. Compared to the control, NLC-ATX, at an optimum ATX concentration under in vitro condition, reduced the amount of generated ROS and DNA damage of 81.6% and 41.6%, respectively, after X-radiation, resulting in a significant decrease in cell death by 62.69%. Under in vivo condition, after the 9th day of X-irradiation (equivalent to an accumulated dose of 14 Gy), the dorsal skin of five out of six NLC-ATX-untreated mice exhibited grade-1 skin damage, according to CTCAE v5.0, while treatment with NLC-ATX protected 6/6 mice from acute skin damage. Moreover, on the 28th day after the first X-irradiation, the histological images illustrated that NLC-ATX at an ATX concentration of 0.25 µg/mL exhibited good recovery of the skin, with barely any difference noted in the collagen fibers and sebaceous glands compared to normal skin. CONCLUSIONS: NLC-ATX shows potential for application in skin protection against adverse effects of ionizing rays during radiotherapy.

Comparison of the radioprotective effects of the liposomal forms of five natural radioprotectants in alleviating the adverse effects of ionising irradiation on human lymphocytes and skin cells in radiotherapy.

This study aims to evaluate the radioprotective effects of liposomes encapsulating curcumin (Lip-CUR), silibinin (Lip-SIL), α-tocopherol (Lip-TOC), quercetin (Lip-QUE) and resveratrol (Lip-RES) in alleviating the adverse effects of ionising irradiation on human lymphoctyes and skin cells in radiotherapy. Liposomes encapsulating the above natural radioprotectants (Lip-NRPs) were prepared by the film hydration method combined with sonication. Their radioprotective effects for the cells against X-irradiation was evaluated using trypan-blue assay and γ-H2AX assay. All prepared Lip-NRPs had a mean diameter less than 240 nm, polydispersity index less than 0.32, and zeta potential more than -23 mV. Among them, the radioprotective effect of Lip-RES was lowest, while that of Lip-QUE was highest. Lip-SIL also exhibited a high radioprotective effect despite its low DPPH-radical scavenging activity (12.9%). The radioprotective effects of Lip-NRPs do not solely depend on the free radical scavenging activity of NRPs but also on their ability to activate cellular mechanisms.

Lasibidoupins A and B, two new compounds from the stems of Lasianthus bidoupensis V.S. Dang & Naiki.

From the Lasianthus bidoupensis stems, two new compounds, including one new 9,10-anthraquinone, lasibidoupin A (1), and one new 6,7-benzocoumarin, lasibidoupin B (2), together with one known compound, 11-O-methyldamnacanthol (3) were isolated using chromatographic method. Their structures were determined by extensive HRMS, and NMR assignments. Compound 3 was reported for the first time from this species. New compounds (1 & 2) were tested for the cytotoxicity against three human cancer cell lines (MCF-7, HeLa, and NCI-H460) by SRB assay. As results, 1 & 2 exhibited significant cytotoxic activity against all cancer cell lines (IC50 ranged from 0.058 ± 0.003 to 0.177 ± 0.014 µM).

Ricicomin A, a new alkaloid from the leaves of Ricinus communis Linn.

From the leaves of Ricinus communis Linn., one new alkaloid, named ricicomin A (1) together with three known ones, ricinine (2), N-demethylricinine (3) and 4-[2-formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]butanoic acid (4) were justified by repeated chromatographic methods. Their structures were determined by comprehensive IR, HR-ESI-MS and NMR analyses. Compound 4 was identified for the first time from the genus Ricinus. DFT-NMR chemical shift calculations and subsequent DP4+ probability methods were applied to confirm the chemical structure of 1. Compounds 1-3 did not display cytotoxic effect against three human cancer cell lines (MCF-7, HepG2 and HeLa) using SRB assay.

Nervione, a new benzofuran derivative from Nervilia concolor.

A new benzofuran derivative, nervione (1), was isolated from Nervilia concolor (Blume) Schltr. (Orchidaceae). Eight previously reported compounds were also isolated: 5,7-dimethoxyflavone (2), 3,5,7-trimethoxyflavone (3), 7-methoxyflavone (4), 3,7-dimethoxy-5-hydroxyflavone (5), tetramethylscutellarein (4',5,6,7-tetramethoxyflavone) (6), 5,7-dimethoxy-4'-hydroxyflavone (7), rhamnetin (8), and 5,7-dihydroxy-3',4'-dimethoxyflavone (9). The structures were elucidated by 1D, 2D NMR, and HRESIMS spectroscopy in addition to the literature. The relative configuration of 1 was defined using DP4+ probability while its absolute configuration was defined by comparison of the ECD spectrum of 1 with those of previously reported compounds. All isolated compounds were evaluated for alpha-glucosidase inhibition, revealing weak or no activity.[Formula: see text].

A new diterpenoid from the leaves of Phyllanthus acidus.

A new diterpenoid, phyllane C (1), along with three known compounds, ovoideal E (2), spruceanol (3), and fluacinoid B (4) were isolated from the leaves of Phyllanthus acidus growing in Thailand. The structures were determined by analysis of their MS and NMR data as well as by comparison with literature values. DFT-NMR chemical shift calculations and subsequent DP4/DP4+ probability methods were applied to define the relative configuration of 1. Compound 3 showed a weak cytotoxicity against K562 cell line (IC50 41.9 ± 2.31 µg/mL).

Cycloartane-type triterpenoids from the whole plants of Macrosolen bidoupensis.

One new cycloartane-type triterpenoid, named macrobidoupoic acid A (as an C-24 epimeric mixture, 4a, 4 b), together with three known ones (1-3), were clarified by different chromatography from the M. bidoupensis whole plants. Triterpenoids (1, 3 & 4) were detected for the first time from the Macrosolen genus. Chemical structures of them were illuminated using HR-ESI-MS, and NMR (1 D & 2 D) assessments. The cytotoxic properties of triterpenoids (3 & 4) were examined against two human cancer cell lines (A549, and RD) by MTT assay. As results shown, triterpenoids (3 & 4) possessed moderate cytotoxic activity against A549 and RD cancer cells (IC50 ranged from 5.44 to 39.52 µM).

A new labdane-type diterpenoid from the leaves of Vitex negundo L.

A new labdane-type diterpenoid, named vitexnegundin (1), along with seven known compounds, including vitexilactone (2), vitetrifolin D (3), 13-hydroxy-5(10),14-halimadien-6-one (4), (rel 3S,5S,8R,9R,10S)-3,9-dihydroxy-13(14)-labden-16,15-olide (5), artemetin (6), vitexcarpin (7) and penduletin (8), were isolated from the leaves of Vitex negundo L. Their structures were elucidated by using spectroscopic methods, X-ray crystallographic analysis and comparison with those reported in the literature. Moreover, all isolated compounds 1-8 were evaluated for their antimicrobial activity against ESBL-producing Escherichia coli strain and methicillin-resistant Staphylococcus aureus.

29-Norlupane-1ß-hydroxy-3,20-dione, a new norlupane triterpenoid from the twigs and leaves of Phyllanthus acidus.

A new norlupane triterpenoid, 29-norlupane-1ß-hydroxy-3,20-dione (1), along with ten known compounds, 29-norlup-1-ene-3,20-dione (2), phyllanthol (3), phyllanthone (4), glochidone (5), lupeol (6), lupeone (7), 4-hydroxybenzoic acid (8), 4-hydroxybenzaldehyde (9), phyllane A (10) and methyl ß-orsellinate (11) were isolated the twigs and leaves of Phyllanthus acidus. The structure of 1 was identified by interpretation of their spectroscopic data and comparison with those reported in the literature. In addition, all isolated compounds 1-11 were evaluated for their antioxidant activity.

Nervisides I-J: Unconventional Side-Chain-Bearing Cycloartane Glycosides from Nervilia concolor.

Two new cycloartane glycosides, nervisides I-J, were isolated from Nervilia concolor whole plants. Their structures were unambiguously established by interpretation of their HRESIMS and 1D and 2D NMR data. These cycloartanes comprised a stereogenic center at C-24, the R configuration of which was assigned based on DFT-NMR calculations and the subsequent DP4 probability score. These compounds were tested for cytotoxicity against K562 and MCF-7 tumor cell lines, revealing mild cytotoxic activity.