The
genus has a wide diversity of species, with an interesting chemical composition of secondary metabolites and applications as medicine. The folk medicine, mainly in developing countries, uses ...species of
to treat seizures, epilepsy and constipation. Though the recognized bioactivity, some Brazilian native species of
remain unexplored, such as
, a native species of Caatinga. This is the first report about the bioactivity of the flowers of
Afr. Fern., a native species of northeast Brazil. In this communication, flavonoids and catechins are identified in
flowers and the chemical composition is linked with its antioxidant, anticholinesterase, and cytotoxic activities. By UPLC-QTOF, some compounds that belong to the class of flavonoids were identified. They are: catechin, epigallocatechin, guibourtinidol-(4α-8)-catechin, and cassiaflavan-(Cat)-epicatechin. The cytotoxic activity is more noticeable for the HL60 (leukemia) cell line with a cell growth inhibition (GI%) of 81.65 ± 5.65.
Compounds isolated from essential oils play an important role in the prevention and treatment of cancer. Monoterpenes are natural products, and the principal constituents of many essential oils. The ...aim of this study was to investigate the cytotoxic potential of p-menthane derivatives. Additionally, analogues of perillyl alcohol, a monoterpene with known anticancer activity, were evaluated to identify the molecular characteristics which contribute to their cytotoxicity, which was tested against OVCAR-8, HCT-116, and SF-295 human tumor cell lines, using the MTT assay. The results of this study showed that (-)-perillaldehyde 8,9-epoxide exhibited the highest percentage inhibition of cell proliferation (GI = 96.32%-99.89%). Perillyl alcohol exhibited high cytotoxic activity (90.92%-95.82%), while (+)-limonene 1,2-epoxide (GI = 58.48%-93.10%), (-)-perillaldehyde (GI = 59.28%-83.03%), and (-)-8-hydroxycarvotanacetone (GI = 61.59%-94.01%) showed intermediate activity. All of the compounds tested were less cytotoxic than perillyl alcohol, except (-)-perillaldehyde 8,9-epoxide (IC50 = 1.75-1.03 µL/mg). In general, replacement of C-C double bonds by epoxide groups in addition to the aldehyde group increases cytotoxicity. Furthermore, stereochemistry seems to play an important role in cytotoxicity. We have demonstrated the cytotoxic influence of chemical substituents on the p-menthane structure, and analogues of perillyl alcohol.
The genus Chamaecrista comprises more than 330 species, with only a few studies on their chemical composition and biologic activities. In this study, the phytochemical profile of leaf, stems, and ...fruits extracts of the C. duckeana were examined by UPLC-ESI-HRMS analysis to determine possibly bioactive constituents. The antioxidant activity was carried out through in vitro assay, by the sequestration of the free radical DPPH. To evaluate the cytotoxic activity of the extracts, an MTT assay was used and the IC50 was determined against HL60 and RAJI cell lines. The metabolic profiles of the botanical parts are dominated by flavonoid class, highlighting isoflavonoids such as daidzin and ononin. All these compounds are reported for the first time in C. duckeana. The extracts presented antioxidant potential, and the activity of the stems extract was higher than the standard butylated hydroxytoluene. In the cytotoxic assay, only HL60 line (leukemia) had growth inhibition over 80%. The stems presented more expressive cytotoxicity with IC50 of 137.3 (104.6-180.1) and 106.8 (96.52-118.3) μmol. L-1 for HL60 and RAJI, respectively. In conclusion, the present work provides an in-depth knowledge about the chemical profile of C. duckeana, a species rich in bioactive secondary metabolites with cytotoxic activity
The main objective of this work was to develop a nanoemulsion based on linseed oil and betulinic acid, stabilized with Pluronic F127 and polyglycerol polyricinoleate, for anticancer applications. The ...nanoemulsions were synthesized by ultrasound and evaluated for in vitro cytotoxicity, particle size, polydispersity index, zeta potential, morphology, encapsulation efficiency, storage stability, rheology and in vitro release kinetics. In vitro cytotoxicity assays were performed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay (72 h) against HCT-116 (colorectal carcinoma), SNB-19 (glioblastoma), NCI-H460 (lung carcinoma) and L-929 (normal fibroblasts) cells. The determination of 50% inhibitory concentration (IC50) showed an increased selectivity for the emulsified betulinic acid when compared to its free form for the HCT-116 cells. The IC50 values for the synthesized nanoemulsions showed a range from 3.2 to 3.7 μM (HCT-116), 5.6 and 11.5 μM (NCI-H460), 5.8 and 7.3 μM (SNB-19) and > 16.5 μM for normal fibroblasts. In the 48 h in vitro release assays, it presented controlled release explained by the Korsmeyer-Peppas model, releasing 572.25 and 619.95 μg of betulinic acid in a controlled way, generating promising perspectives for the prolonged release of betulinic acid in anticancer applications.
Fibroblast cycle synchronization in G
0
/G
1
is an essential step for nuclear reprogramming by cloning or induced cells to pluripotency. Considering the diversity among rodents and the ecological and ...scientific importance of these animals, we compared the contact inhibition, serum starvation, and 10 µM of roscovitine as methods of synchronization of red-rumped agouti fibroblasts. The effects of each protocol were evaluated on the percentage of cycle phase, morphology, viability, and apoptosis levels. The results showed that culturing the cells to serum starvation for 24 h (75.9%), 48 h (81.6%), 72 h (86.2%), 96 h (84.0%), and 120 h (83.7%) yielded a significantly higher percentage of cells arrested in the G
0
/G
1
(
P
< 0.05) phase than cells not subjected to any cell cycle synchronization method (31.4%). Also, this effect was not different between the times of 48 and 120 h (
P
> 0.05). A similar response was observed for cells cultured with roscovitine for 12 h (86.9%), 24 h (74.8%), and 48 h (81.7%), with a higher percentage of synchronized cells in G
0
/G
1
compared to cells not submitted to any synchronization treatment (52.2%). Nevertheless, this effect was best evidenced at 12 h (
P
< 0.05). Also, the contact inhibition for 24–120 h could not synchronize cells in G
0
/G
1
, with values ranging from 70.9 to 77.9% (
P
> 0.05). Moreover, no difference was observed for morphology, viability, and apoptosis levels in any synchronization method (
P
> 0.05). Therefore, serum starvation is as efficient as roscovitine on cycle synchronization in G
0
/G
1
of red-rumped agouti fibroblasts.
Human epidermal receptors (HER1/2/3/4) belong to the class of receptor-type tyrosine kinases. After binding a ligand, dimerization, it will ocurr activation of intracellular kinases after ...two-dimensional and cytoplasmic tail reciprocal transphosphorylation. This transphosphorylation recruits signaling pathways such as Ras/Raf/MEK/Erk1-2, PI3-K/AKT and JAK/STAT, which can affect the cell cycle, cytoskeleton reorganization, apoptosis, metastasis, differentiation, angiogenesis and transcription. HER deregulation is found in epithelial, mesenchymal and nervous neoplasms and is associated with poor prognosis and tumor severity. Since HER are promiscuous proteins when subjected to mutations, resultant modifications confer cellular metabolic superiority and activate complex, interconnected and overlapping networks of cytoplasmic signaling. Moreover, overexpression of HER1/2 is involved in tumor resistance to radiation and anti-hormone therapies. Indeed, HER2 expression is up to 100-fold higher in 25-30% of invasive breast cancers. These characteristics support the development of resistance to anti-HER1/2 chemotherapy such as monoclonal antibodies and tyrosine kinase inhibitors. Then, the challenges in research with HER-positive cancers include planning therapeutic strategies against known resistance mechanisms and identifying novel mechanisms as a way to overcome and control cell growth and malignant progression.
A new nor-ent-kaurene diterpene and ten other compounds were isolated from Annona vepretorum stems, including four kaurene diterpenes, three alkamides, one sesquiterpene and two steroids. Their ...chemical structures were elucidated using spectroscopic methods, including 1D-, 2D-NMR, and HRESIMS. The absolute configuration of compounds 1, 5, 8, 9 and 10 was confirmed by CD experiments. Compounds 1-5 and 8-10 were evaluated for cytotoxic activity using (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT method, against three human carcinoma cell lines: human colon (HCT-116), glioblastoma (SF295) and prostate (PC3). However, all isolated compounds exhibited low cytotoxic activity.
The main goal was the development of a polysaccharide microcapsule for anticancer application based on guar gum and sodium alginate for the controlled release of hesperidin and betulinic acid by ...spray drying technique. The microcapsule showed an Encapsulation Efficiency of 98.15 ± 0.34 % for hesperidin and 99.76 ± 0.22 % for betulinic acid. In the release study, the Korsmeyer-Peppas mathematical model was identified as the most adequate to explain the observed release mechanism. In vivo tests were performed in zebrafish model, revealing that the microcapsules did not alter the locomotor activity and were not toxic within 96 h by oral administration, suggesting their biological safety. In vitro cytotoxic activity against HL-60 cells confirmed an IC50 value of 2.52 ± 0.23 μg mL−1 in 72 h. Additionally, a decrease in the cytotoxic activity of betulinic acid against L-929 (non-tumor) cells was evidenced. Therefore, the microcapsules synthesized in this work represent a promising formulation for anticancer applications.
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The first synthesis of the natural product (+)-mutisianthol was accomplished in 11 steps and in 21% overall yield from 2-methylanisole. The synthesis of its enantiomer was also performed in a similar ...overall yield. The absolute configuration of the sesquiterpene (+)-mutisianthol was assigned as (1S,3R). Key steps in the route are the asymmetric hydrogenation of a nonfunctionalized olefin using chiral iridium catalysts and the ring contraction of 1,2-dihydronaphthalenes using thallium(III) or iodine(III). The target molecules show moderate activity against the human tumor cell lines SF-295, HCT-8, and MDA-MB-435.
Docetaxel (DTX) is a non-selective antineoplastic agent with low solubility and a series of side effects. The technology of pH-sensitive and anti-epidermal growth factor receptor (anti-EGFR) ...immunoliposomes aims to increase the selective delivery of the drug in the acidic tumor environment to cells with EFGR overexpression. Thus, the study aimed to develop pH-sensitive liposomes based on DOPE (dioleoylphosphatidylethanolamine) and CHEMS (cholesteryl hemisuccinate), using a Box-Behnken factorial design. Furthermore, we aimed to conjugate the monoclonal antibody cetuximab onto liposomal surface, as well as to thoroughly characterize the nanosystems and evaluate them on prostate cancer cells. The liposomes prepared by hydration of the lipid film and optimized by the Box-Behnken factorial design showed a particle size of 107.2 ± 2.9 nm, a PDI of 0.213 ± 0.005, zeta potential of -21.9 ± 1.8 mV and an encapsulation efficiency of 88.65 ± 20.3%. Together, FTIR, DSC and DRX characterization demonstrated that the drug was properly encapsulated, with reduced drug crystallinity. Drug release was higher in acidic pH. The liposome conjugation with the anti-EGFR antibody cetuximab preserved the physicochemical characteristics and was successful. The liposome containing DTX reached an IC
at a concentration of 65.74 nM in the PC3 cell line and 28.28 nM in the DU145 cell line. Immunoliposome, in turn, for PC3 cells reached an IC
of 152.1 nM, and for the DU145 cell line, 12.60 nM, a considerable enhancement of cytotoxicity for the EGFR-positive cell line. Finally, the immunoliposome internalization was faster and greater than that of liposome in the DU145 cell line, with a higher EGFR overexpression. Thus, based on these results, it was possible to obtain a formulation with adequate characteristics of nanometric size, a high encapsulation of DTX and liposomes and particularly immunoliposomes containing DTX, which caused, as expected, a reduction in the viability of prostate cells, with high cellular internalization in EGFR overexpressing cells.
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