RSC Advances

Guerra, Jorge Rodríguez; Cárdenas, Andrea Barragán; Ochoa-Zarzosa, Alejandra; Meza, Joel López; Umaña Pérez, Adriana; Fierro-Medina, Ricardo; Rivera Monroy, Zuly Jenny; García Castañeda, Javier Eduardo

doi: 10.1039/c9ra04145apmid: 35515557

The cytotoxic effect of the tetrameric peptide LfcinB (20–25)4 against breast cancer cell line ATCC® HTB-22™ (MCF-7) was evaluated. The tetrameric peptide exhibited a concentration-dependent cytotoxic effect against MCF-7 cancer cells. The peptide at 22 µM had the maximum cytotoxic effect against MCF-7 cancer cells, reducing their cell viability to ∼20%. The cytotoxic effect of the tetrameric peptide against MCF-7 cells was sustained for 24 hours. Furthermore, the tetrameric peptide did not exhibit a significant cytotoxic effect against the non-tumorogenic trophoblastic cell line, which confirms their selectivity for breast cancer cell lines. The MCF-7 cells treated at 12.2 µM for 1 h exhibited morphological changes characteristic of apoptosis, such as rounded forms and cellular shrinkage. Furthermore, this peptide induces severe cellular damage to MCF-7 cells, mitochondrial membrane depolarization, and increase of cytoplasmic calcium concentration. Our results suggest that it has a significant selective cytotoxic effect against MCF-7 cells, which may be mainly associated with the apoptotic pathway. This peptide, which contains the RRWQWR motif, could be considered to be a promising candidate for developing therapeutic agents for the treatment of breast cancer.

Hu, Mixia; Yan, YaLi; Zhu, Baohua; Chang, Fei; Yu, Shiyong; Alatan, Gaole

doi: 10.1039/c9ra01370apmid: 35515566

Five Mn(i) photo-activated carbon monoxide-releasing molecules (photo-CORMs) with benzimidazole coligands, namely [MnBr(CO)3L1] (1, L1 = 2-(2-pyridyl)benzimidazole), [Mn(CO)2L1(PPh3)2](ClO4) (2), [MnBr(CO)3L2] (3, L2 = 2,2′-bisbenzimidazole), [MnBr(CO)3L3]·CH3OH (4, L3 = 2,6-bis(benzimidazole-2′-yl)pyridine) and fac-[MnBr(CO)3L4] (5, L4 = 2,4-bis(benzimidazole-2′-yl) pyridine) were synthesized by reactions of MnBr(CO)5 with complexes L1–L4, respectively, and characterized via single crystal X-ray diffraction, elemental analysis, 1H-NMR, 13C-NMR, IR, UV-vis and fluorescence spectroscopy. The CO-release properties of 1–5 were investigated using the myoglobin assay and CO detection, and the results show that all of the complexes could release CO rapidly upon exposure to 365 nm UV light. Comparing their half-lives of CO release, we found that increasing the degree of unsaturation and conjugation of the ligand frame could be advantageous for prolonging the time of CO-release, and that the luminescence intensity of 1–5 could gradually be enhanced. The cellular fluorescence imaging tests demonstrate that these Mn(i) photo-CORMs can be taken up by human liver cells (HL-7702) and liver cancer cells (SK-Hep1), and exhibit good capabilities for bioimaging. A cell viability assay for SK-Hep1 shows that the anticancer activity of 3 is better than that of other complexes.

Zhang, Guyu; Zhu, Yimin; Wang, Yushu; Wei, Dengshuai; Wu, Yixin; Zheng, Liuchun; Bai, Huimin; Xiao, Haihua; Zhang, Zhenyu

doi: 10.1039/c9ra04034jpmid: 35515556

pH/redox sensitive, dual drug loaded nanoparticles were prepared from poly(ethylene glycol)-block-poly(l-lysine) (PEG-b-PLL) for improving cancer therapy. Platinum(iv) and cis-aconitic anhydride-doxorubicin (CAD) were anchored to lysine residual amine groups of PLL to form polymer prodrug conjugates, which then self-assembled into nanoparticles with hydrophobic platinum(iv) prodrugs and CAD as the core. The nanoparticles were stable in neutral environments, but once under acidic and reductive conditions, the drugs were rapidly released. The dual-loaded nanoparticles had comparable intracellular toxicity to the regimen of combined application of free cisplatin and doxorubicin.

Chantarasrivong, Chanikarn; Higuchi, Yuriko; Tsuda, Masahiro; Yamane, Yuuki; Hashida, Mitsuru; Konishi, Miku; Komura, Naoko; Ando, Hiromune; Yamashita, Fumiyoshi

doi: 10.1039/c9ra01943jpmid: 35515515

In this study, we developed novel E-selectin-targeting liposomes, i.e., 3′-(1-carboxy)ethyl sialyl LewisX (3′-CE sLeX) mimic liposomes, for targeted delivery of everolimus (EVE) in anti-angiogenic therapy. We investigated the uptake and efficacy of these E-selectin targeting liposomes in inflammatory cytokine-treated human umbilical vein endothelial cells (HUVECs). The uptake of EVE in 3′-CE sLeX mimic liposomes increased steadily and almost caught up with the uptake of plain EVE at 3 h, which was higher than that in PEGylated liposomes (PEG-liposomes). Inhibition of uptake by anti-E-selectin antibody suggested involvement of E-selectin-mediated endocytotic processes. Migration in cells treated with EVE/3′-CE sLeX mimic liposomes was suppressed by more than half when compared to the control. This treatment was also seen to significantly inhibit the formation of capillary tubes and networks. In addition, Thr389 phosphorylation of pS6 kinase, as a marker of mTOR activity, was remarkably suppressed to less than endogenous levels by EVE/3′-CE sLeX mimic liposomes. In conclusion, the present study demonstrated that EVE/3′-CE sLeX mimic liposomes were intracellularly taken up by E-selectin and prompted anti-angiogenic effects of EVE involved in the mTOR signaling pathway. However, moderate retention of EVE in the liposomes might limit the targeting ability of 3′-CE sLeX mimic liposomes.

Mu, Liang; Feng, WeiWei; Zhang, Haobin; Hu, Xiubin; Cui, Qingyan

doi: 10.1039/c9ra03324fpmid: 35515569

A small crystal NaY zeolite with a high SiO2/Al2O3 ratio was successfully synthesized with seeding and without organic template, and the effects of the silicon source, aging time and Na2O seeding content on the crystal size of NaY zeolite were investigated. The synthesized samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-Transform Infrared (FT-IR) spectroscopy and N2 adsorption–desorption. The results showed that the silicon source used to prepare seeding had a great effect on the crystal size of NaY zeolite, NaY zeolite with average size of 100 nm and SiO2/Al2O3 ratio of 5.42 was obtained by using the seeding prepared with silica sol. Moreover, the crystal size of NaY zeolite decreased with an extension of the aging time and an increase of the Na2O content of seeding. The catalytic performance of small crystal Y zeolite was evaluated in the hydrocracking of vacuum gas oil (VGO), the catalyst with smaller crystal Y zeolite presented higher VGO conversion and middle distillates selectivity than those with larger ones due to its higher surface area and more amount of mesoporous.

, Kriti; Kaur, Puneet; Kaur, Simranpreet; Arora, Deepawali; Asokan, K.; Singh, D. P.

doi: 10.1039/c9ra01901dpmid: 35686289

The present study reports the impact of thermal annealing on the structural, optical and magnetic properties of WO3 nanostructures, synthesized using an acid precipitation method by, employing various spectroscopic and magnetic measurements. The X-ray diffraction and Raman measurements confirmed the orthorhombic structure of as dried WO3·H2O and monoclinic structure of WO3 nanopowders annealed at or above 500 °C. The morphological characterization shows the formation of different microstructures like nanosheets, nanoplatelets and nanocuboids in the micro-scale with the variation of annealing temperatures. The optical band gap has been calculated using the Kubelka–Munk function. The room temperature photoluminescence (PL) spectra recorded at different excitation wavelengths show intense near ultraviolet (NUV) emission which might be due to the presence of localized states associated with oxygen vacancies, and the surface states in the conduction band. The emissions in visible region correspond to the structural defects such as oxygen vacancies present within the band gap and band to band transitions. The spectral chromaticity colour coordinates indicate that the light emitted from the prepared samples shows shift from violet to red region with the change of excitation wavelength. Magnetic measurements show decrease in room temperature ferromagnetism (FM) with annealing temperature. The X-ray absorption spectroscopy (XAS) measurements at O K-edge show the significant change in the W–O hybridizations. The decrease in PL intensity and ferromagnetic ordering with increase in annealing temperatures are directly correlated with the filling up of oxygen vacancies in the samples. The oxygen vacancies based F-Center exchange model is discussed to understand the origin of FM in WO3 nanostructures.

Hu, Fang; Xie, Di; Cui, Fuhan; Zhang, Dongxu; Song, Guihong

doi: 10.1039/c9ra04339jpmid: 35515541

NaV3O8 nanobelts were successfully synthesized for Li/Na-ion batteries and rechargeable aqueous zinc-ion batteries (ZIBs) by a facile hydrothermal reaction and subsequent thermal transformation. Compared to the electrochemical performance of LIBs and NIBs, NaV3O8 nanobelt cathode materials in ZIBs have shown excellent electrochemical performance, including high specific capacity of 421 mA h g−1 at 100 mA g−1 and good cycle stability with a capacity retention of 94% over 500 cycles at 5 A g−1. The good diffusion coefficients and high surface capacity of NaV3O8 nanobelts in ZIBs were in favor of fast Zn2+ intercalation and long-term cycle stability.

Qiao, Yi-Jun; Zhang, Jia-Jiao; Shang, Jia-Huan; Zhu, Hong-Tao; Wang, Dong; Yang, Chong-Ren; Zhang, Ying-Jun

doi: 10.1039/c9ra02110hpmid: 35515514

Continuous cropping obstacle, mainly caused by microorganisms and organic components in soil, has become a serious problem for the plantation of Panax notoginseng (Araliaceae) due to the rapidly increased demands of this famous herbal medicine in recent decades. The rhizosphere soils cultivated with 3-year-old healthy and ill notoginseng were chemically investigated by gas chromatography-mass spectrometry (GC-MS) and compared with the corresponding soils without the plantation of notoginseng. Totally 47 liposoluble components were identified. Furthermore, the multiple statistical analysis showed that these constituents were qualitatively and quantitatively associated with the differences between the cultivated soil with P. notoginseng and the uncultivated soil. Among them, neophytadiene (4), d-α-tocopherol (38), (3β,22E,24S)-ergosta-5,22-dien-3-ol (39), (3β,24R)-ergost-5-en-3-ol (40), stigmasta-5,22-dien-3-ol (41), stigmast-4-en-3-one (44) and (5α)-stigmastane-3,6-dione (47) contributed most to the significant differences between the cultivated and uncultivated soils, whereas cyclopentadecane (3), octadecanoic acid methyl ester (16), docosanoic acid ethyl ester (31), nonacosane (34), 38 and 39 were found in much higher amount in the soils with ill P. notoginseng as compared to the case of those with the healthy P. notoginseng. On the other hand, liposoluble components in different cultivation areas were of great diversity; however, they were able to remain relatively consistent across the overall trend of differential substances.

Locarno, Silvia; Eleta-Lopez, Aitziber; Lupo, Maria Giovanna; Gelmi, Maria Luisa; Clerici, Francesca; Bittner, Alexander M.

doi: 10.1039/c9ra02486gpmid: 35515570

We investigate the electrospinning of small molecules, specifically designed peptide derivatives of the pyrazole-isothiazole scaffold. Such non-natural peptides enhance the spectrum of fundamental materials used for electrospinning. Unlike standard electrospun materials, our peptides are not polymeric, but able to aggregate in solution and especially during processing. They contain donor/acceptor groups that can form hydrogen bonds, and groups that are able to generate π-stacking interactions, which are known as important requirements for assembly processes. The pyrazole-isothiazole derivatives were synthesized by means of a 1,3-dipolar cycloaddition reaction, which is completely regioselective, affording only one isomer. We demonstrate that our compounds can be electrospun from fluoroalcohol solution into solid, quasi-endless micro- and nanofibers. The electrospinnability varies substantially, depending on the amino acids linked to the scaffold. Some compounds provide only short fibers, while Fmoc-glycyl-(N-benzyl)-pyrazole-isothiazole-tert-butyl carboxylate-1,1-dioxide forms continuous, homogenous, and bead-free fibers (droplet-like beads are a common problem in electrospinning). We analyzed the compounds and the fibers with various spectroscopic techniques (MS, IR and Raman). Electrospinning does not change chemical composition and configuration, suggesting the monomeric form of the compounds even in the fibers. Interestingly, we found that the stereochemistry of the scaffold can affect the ability of the peptide to be electrospun.

Ahmed, Owais; Cherkadu, Vandana; Kalavagunta, Praveen Kumar; Shang, Jing

doi: 10.1039/c9ra02763gpmid: 35515575

Using 2-propanol as the solvent, 3-formylchromones and 2-aminobenzothiaoles formed corresponding imines, while 1° and 2°-alcohols formed the corresponding 2-alkoxy-3-enamines with selectivity for the Z-isomer. Changing the substrates with similar molecules such as 3-formylchromone with quinoline-, quinolone- and indole-3-carbaldehydes sometimes resulted in the formation of the corresponding imines, whereas replacing 2-aminobenzothiazole with amides resulted in the formation of acetals. Considering the effect of the solvent, replacing alcohols with the aprotic solvents THF and CH2Cl2 resulted in the formation of imines and enamines, which are the characteristic reactions of 2-propanol and other 1° and 2°-alcohols, respectively. 2-Alkoxy-3-enamines were found to undergo transacetalization with both short and long chain alcohols. The novelty of these reactions is that they did not require an external catalyst, all the reactions were performed at the same temperature, and purification was achieved by filtration. The transacetalization we performed herein is a new concept, which has not been reported to date. In contrast, other similar reactions, such as transalkoxylation, transalkylation, and transetherification, are performed on a commercial scale using expensive catalysts such as Otera's catalyst. The highly sensitive nature of 3-formylchromones towards variations in the substrates and solvents to form different products and the reason behind the selective formation of the Z-isomer of 2-alkoxy-3-enamines and its transacetalization efficiency need further studies to understand the reaction mechanism and possibly other factors such as solvent effects.