958 research outputs found
The novel diterpene 7\u3b2-acetoxy-20-hydroxy-19,20-epoxyroyleanone from Salvia corrugata shows complex cytotoxic activities against human breast epithelial cells
Aims
The aim of this study was the characterization of the in vitro cytotoxic properties of a recently isolated diterpene compound, 7\u3b2-acetoxy-20-hydroxy-19,20-epoxyroyleanone (compound 1), extracted from Salvia corrugata, versus human cell lines.
Main Methods
We used as model study immortalized breast epithelial cells MCF10A and two ERBB2+ breast cancer (BCa) cell lines, SKBR-3 and BT474. Compound 1 was isolated by methanolic extraction from regenerated shoots of Salvia corrugata Vahl, and purified by high pressure liquid chromatography (HPLC). Flow cytometry (FCM) was employed for cell cycle, apoptosis and reactive oxygen species (ROS) analysis. Cell morphology was assessed by immunofluorescence and transmission electron microscopy (TEM).
Key Findings
Compound 1 inhibited cell survival of all breast cell lines. In particular, compound 1 promoted cell cycle arrest in the G0/G1 phase and apoptosis along with impairment of the mitochondrial function, which was reflected in a gross alteration of the mitochondrial network structure. Furthermore, we also detected a potent activation of the ERK1/2 kinase, which suggested the induction of reactive oxygen species (ROS). Partial rescue of survival obtained with n-acetylcysteine (NAC) when coadminstered with compound 1 further supported a contribution of ROS mediated mechanisms to the growth-arrest and proapoptotic activity of compound 1 in both BCa cell lines. ROS production was indeed confirmed in SKBR-3.
Significance
Our findings show that compound 1 has a cytotoxic activity against both human normal and cancer cell lines derived from breast epithelia, which is mediated by ROS generation and mitochondrial damage
Adaptive deep brain stimulation in a freely moving parkinsonian patient
The future of deep brain stimulation (DBS) for Parkinson\u2019s disease (PD) lies in new closed-loop systems that continuously
supply the implanted stimulator with new settings obtained by analyzing a feedback signal related to the patient\u2019s current
clinical condition
Cooperative antitumor activities of carnosic acid and Trastuzumab in ERBB2+ breast cancer cells
Background: ERBB2 is overexpressed in up to 20\u201330% of human breast cancers (BCs), and it is associated with
aggressive disease. Trastuzumab (Tz), a humanized monoclonal antibody, improves the prognosis associated with
ERBB2-amplified BCs. However, the development of resistance remains a significant challenge. Carnosic acid
(CA) is a diterpene found in rosemary and sage, endowed with anticancer properties. In this in vitro study,
we have investigated whether Tz and CA have cooperative effects on cell survival of ERBB2 overexpressing
(ERBB2+) cells and whether CA might restore Tz sensitivity in Tz-resistant cells.
Methods: We have studied BC cell migration and survival upon CA and Tz treatment. In particular, migration
ability was assessed by transwell assay while cell survival was assessed by MTT assay. In addition, we have performed cell
cycle and apoptosis analysis by high-resolution DNA flow cytometry and annexin-V, resazurin and sytox blue staining by
flow cytometry, respectively. The expression of proteins involved in cell cycle progression, ERBB2 signaling
pathway, and autophagy was evaluated by immunoblot and immunofluorescence analysis. Cellular structures
relevant to the endosome/lysosome and autophagy pathways have been studied by immunofluorescence and
transmission electron microscopy.
Results: We report that, in ERBB2+ BC cells, CA reversibly enhances Tz inhibition of cell survival, cooperatively
inhibits cell migration and induces cell cycle arrest in G0/G1. These events are accompanied by ERBB2 downregulation,
deregulation of the PI3K/AKT/mTOR signaling pathway and up-regulation of both CDKN1A/p21WAF1
and CDKN1B/p27KIP1. Furthermore, we have demonstrated that CA impairs late autophagy and causes derangement of
the lysosomal compartment as shown by up-regulation of SQSTM1/p62 and ultrastructural analysis. Accordingly, we
have found that CA restores, at least in part, sensitivity to Tz in SKBR-3 Tz-resistant cell line.
Conclusions: Our data demonstrate the cooperation between CA and Tz in inhibiting cell migration and survival of
ERBB2+ BC cells that warrant further studies to establish if CA or CA derivatives may be useful in vivo in the treatment
of ERBB2+ cancers
Cognitive safety of eight-hours adaptive deep brain stimulation (aDBS) in Parkinson's disease
Dually Cross-Linked Core-Shell Structure Nanohydrogel with Redox–Responsive Degradability for Intracellular Delivery
A redox-responsive nanocarrier is a promising strategy for the intracellular drug release because
it protects the payload, prevents its undesirable leakage during extracellular transport, and favors
site-specific drug delivery. In this study, we developed a novel redox responsive core-shell structure
nanohydrogel prepared by a water in oil nanoemulsion method using two biocompatible synthetic
polymers: vinyl sulfonated poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate)-polyethylene
glycol-poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate) triblock copolymer, and thiolated
hyaluronic acid. The influence on the nanohydrogel particle size and distribution of formulation
parameters was investigated by a three-level full factorial design to optimize the preparation conditions.
The surface and core-shell morphology of the nanohydrogel were observed by scanning electron
microscope, transmission electronmicroscopy, and further confirmed by Fourier transforminfrared spectroscopy
and Raman spectroscopy from the standpoint of chemical composition. The redox-responsive
biodegradability of the nanohydrogel in reducing environments was determined using glutathione as
reducing agent. A nanohydrogel with particle size around 250 nm and polydispersity index around
0.1 is characterized by a thermosensitive shell which jellifies at body temperature and crosslinks at the
interface of a redox-responsive hyaluronic acid core via theMichael addition reaction. The nanohydrogel
showed good encapsulation efficiency for model macromolecules of different molecular weight (93%
for cytochrome C, 47% for horseradish peroxidase, and 90% for bovine serum albumin), capacity to
retain the peroxidase-like enzymatic activity (around 90%) of cytochrome C and horseradish peroxidase,
and specific redox-responsive release behavior. Additionally, the nanohydrogel exhibited excellent
cytocompatibility and internalization efficiency into macrophages. Therefore, the developed core-shell
structure nanohydrogel can be considered a promising tool for the potential intracellular delivery of
different pharmaceutical applications, including for cancer therapy
Innovative In Vitro Strategy for Assessing Aluminum Bioavailability in Oral Care Cosmetics
Aluminum is an element found in nature and in cosmetic products. It can interfere with the metabolism of other cations, thus inducing gastrointestinal disorder. In cosmetics, aluminum is used in antiperspirants, lipsticks, and toothpastes. The aim of this work is to investigate aluminum bioavailability after accidental oral ingestion derived from the use of a toothpaste containing a greater amount of aluminum hydroxide than advised by the Scientific Committee on Consumer Safety (SCCS). To simulate in vitro toothpaste accidental ingestion, the INFOGEST model was employed, and the amount of aluminum was measured through the ICP-AES analysis. Tissue barrier integrity was analyzed by measuring transepithelial electric resistance, and the tissue architecture was checked through light microscopy. The margin of safety was also calculated. Overall, our results indicate that the acute exposure to aluminum accidentally ingested from toothpastes is safe for the final user, even in amounts higher than SCCS indications
Nitric oxide synthetic pathway and cGMP levels are altered in red blood cells from end-stage renal disease patients
Characterization of hepatitis B virus X gene quasispecies complexity in mono-infection and hepatitis delta virus superinfection
Hepatitis B X gene; Hepatitis B virus; Hepatitis delta virusHepatitis B gen X; Virus d'hepatitis B; Virus d'hepatitis deltaHepatitis B gen X; Virus de hepatitis B; Virus de hepatitis deltaBACKGROUND:
Hepatitis delta virus (HDV) seems to strongly suppress hepatitis B virus (HBV) replication, although little is known about the mechanism of this interaction. Both these viruses show a dynamic distribution of mutants, resulting in viral quasispecies. Next-generation sequencing is a viable approach for analyzing the composition of these mutant spectra. As the regulatory hepatitis B X protein (HBx) is essential for HBV replication, determination of HBV X gene (HBX) quasispecies complexity in HBV/HDV infection compared to HBV mono-infection may provide information on the interactions between these two viruses.
AIM:
To compare HBV quasispecies complexity in the HBX 5' region between chronic hepatitis delta (CHD) and chronic HBV mono-infected patients.
METHODS:
Twenty-four untreated patients were included: 7/24 (29.2%) with HBeAg-negative chronic HBV infection (CI, previously termed inactive carriers), 8/24 (33.3%) with HBeAg-negative chronic hepatitis B (CHB) and 9/24 (37.5%) with CHD. A serum sample from each patient was first tested for HBV DNA levels. The HBX 5' region [nucleotides (nt) 1255-1611] was then PCR-amplified for subsequent next-generation sequencing (MiSeq, Illumina, United States). HBV quasispecies complexity in the region analyzed was evaluated using incidence-based indices (number of haplotypes and number of mutations), abundance-based indices (Hill numbers of order 1 and 2), and functional indices (mutation frequency and nucleotide diversity). We also evaluated the pattern of nucleotide changes to investigate which of them could be the cause of the quasispecies complexity.
RESULTS:
CHB patients showed higher median HBV-DNA levels [5.4 logIU/mL, interquartile range (IQR) 3.5-7.9] than CHD (3.4 logIU/mL, IQR 3-7.6) (P = n.s.) or CI (3.2 logIU/mL, IQR 2.3-3.5) (P < 0.01) patients. The incidence and abundance indices indicated that HBV quasispecies complexity was significantly greater in CI than CHB. A similar trend was observed in CHD patients, although only Hill numbers of order 2 showed statistically significant differences (CHB 2.81, IQR 1.11-4.57 vs CHD 8.87, 6.56-11.18, P = 0.038). There were no significant differences in the functional indices, but CI and CHD patients also showed a trend towards greater complexity than CHB. No differences were found for any HBV quasispecies complexity indices between CHD and CI patients. G-to-A and C-to-T nucleotide changes, characteristic of APOBEC3G, were higher in CHD and CI than in CHB in genotype A haplotypes, but not in genotype D. The proportion of nt G-to-A vs A-to-G changes and C-to-T vs T-to-C changes in genotype A and D haplotypes in CHD patients showed no significant differences. In CHB and CI the results of these comparisons were dependent on HBV genotype.
CONCLUSION:
The lower-replication CHD and CI groups show a trend to higher quasispecies complexity than the higher-replication CHB group. The mechanisms associated with this greater complexity require elucidation.Supported by the Instituto de Salud Carlos III, grants PI15/00856 and PI17/02233; co-financed by the European Regional Development Fund (ERDF
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