Essential thrombocythemia (ET) is a blood cancer caused by mutations in
and
. It is widely recognized that both mutations lead to the constitutive activation of JAK2/STAT signaling, although other ...JAK/STAT-independent pathogenic mechanisms triggered by these alterations have also been described in ET. In an attempt to study JAK2/STAT-independent mechanisms derived from
mutations, our research group created a
model with patient-like mutations in calreticulin that lacks JAK counterparts. The introduction of patient-like mutations in the calreticulin of
leads to an increase in the transcriptional expression of
, independently of JAK2/STAT activation. In the present study, we aim to verify if this mechanism is conserved in patients with ET harboring
mutations. To do so, we evaluated the expression of potential orthologs of
in human cell lines of interest for the study, as well as in bone marrow (BM) or peripheral blood (PB) mononuclear cells from patients with
or
mutations. The results revealed that this mechanism is conserved in
-mutated ET patients, since
, but not
mutations, were associated with an overexpression of
in patients with ET. The use of drugs targeting the activation or blockade of this target in the analyzed cell lines did not result in changes in cell viability. However,
might be relevant in the disease, pointing to the need for future research testing retinoids and other drugs targeting RXRα for the treatment of ET patients.
The characterization of compounds with antioxidant activity is of great interest due to their ability to reduce reactive oxygen species production and, therefore, prevent some age-related diseases. ...Its antioxidant capacity can be analyzed by different methods both in vitro and in vivo.
is an in vivo model widely used in ageing research. Until now, available tests analyze functional effects in the worms, so the antioxidant activity of the compound is indirectly monitored. We have developed a simple and a reliable method to quantify internal antioxidant activity in vivo. To validate this method, we analyzed an aqueous green tea extract and two other compounds with a well-known antioxidant activity and without this activity. The results obtained (EC
green tea = 21.76 ± 1.28 µg/mL; EC
positive control = 8.50 ± 0.33 µg/mL; negative control EC
> 500 µg/mL) can help in the design of further in vivo experiments. Thus, our method can be used as a previous screening capable of reducing the gap between in vitro and in vivo assays.
Phenolic compounds might modulate adiposity. Here, we report our observation that polyphenols and phenolic acids inhibit adipogenesis in 3T3-L1 with different intensity depending on the family and ...the stage of differentiation. While quercetin and resveratrol inhibited lipid accumulation along the whole process of differentiation, apigenin and myricetin were active during the early and latest stages, but not intermediate, contrary to hesperidin. The activity of phenolic acids was limited to the early stages of the differentiation process, except
-coumaric and ellagic acids. This anti-adipogenic effect was accompanied by down-regulation of
and
. Molecular docking analysis revealed that the inhibitory activity of these phenolic compounds over the early stages of adipogenesis exhibits a significant correlation (
= 0.7034;
= 0.005) with their binding affinity to the ligand-binding domain of PPARγ. Results show that polyphenols and phenolic acids would interact with specific residues of the receptor, which could determine their potential anti-adipogenic activity during the early stages of the differentiation. Residues Phe264, His266, Ile281, Cys285 and Met348 are the most frequently involved in these interactions, which might suggest a crucial role for these amino acids modulating the activity of the receptor. These data contribute to elucidate the possible mechanisms of phenolic compounds in the control of adipogenesis.
-negative myeloproliferative neoplasms (polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF)) are infrequent blood cancers characterized by signaling aberrations. ...Shortly after the discovery of the somatic mutations in JAK2, MPL, and CALR that cause these diseases, researchers extensively studied the aberrant functions of their mutant products. In all three cases, the main pathogenic mechanism appears to be the constitutive activation of JAK2/STAT signaling and JAK2-related pathways (MAPK/ERK, PI3K/AKT). However, some other non-canonical aberrant mechanisms derived from mutant JAK2 and CALR have also been described. Moreover, additional somatic mutations have been identified in other genes that affect epigenetic regulation, tumor suppression, transcription regulation, splicing and other signaling pathways, leading to the modification of some disease features and adding a layer of complexity to their molecular pathogenesis. All of these factors have highlighted the wide variety of cellular processes and pathways involved in the pathogenesis of MPNs. This review presents an overview of the complex signaling behind these diseases which could explain, at least in part, their phenotypic heterogeneity.
Essential thrombocythemia (ET) is one of the most common types of Ph-negative myeloproliferative neoplasms, an infrequent group of blood cancers that arise from a CD34 + hematopoietic stem cell (HSC) ...in the bone marrow (BM) primarily due to driver mutations in JAK2, CALR or MPL. These aberrations result in an overproduction of mature myeloid cells in peripheral blood (PB). To date, no targeted therapies have been approved for ET patients, so the study of the molecular mechanisms behind the disease and the identification of new therapeutic targets may be of interest. For this reason, in this study, we have compared the transcriptomic profile of undifferentiated CD34 + cells and mature myeloid cells from ET patients (CALR and JAK2-mutated) and healthy donors deposited in publicly available databases. The study of the similarities and differences between these samples might help to better understand the molecular mechanisms behind the disease according to the degree of maturation of the malignant clone and the type of mutation and ultimately help identify new therapeutic targets for these patients.
The results show that most of the altered hallmarks in neutrophils were also found in CD34 + cells. However, only a few genes showed a similar aberrant expression pattern in both types of cells. We have identified a signature of six genes common to patients with CALR and JAK2 mutations (BPI, CRISP3, LTF, MMP8, and PTGS1 upregulated, and PBXIP1 downregulated), a different signature of seven genes for patients with CALR mutations (BMP6, CEACAM8, ITK, LCN2, and PRG2 upregulated, and MAN1A1 and MME downregulated) and a signature of 13 genes for patients with JAK2 mutations (ARG1, CAST, CD177, CLEC5A, DAPP1, EPS15, IL18RAP, OLFM4, OLR1, RIOK3, SELP, and THBS1 upregulated, and IGHM downregulated).
Our results highlight transcriptomic similarities and differences in ET patients according to the degree of maturation of the malignant clone and the type of mutation. The genes and processes altered in both CD34 + cells and mature neutrophils may reveal altered sustained processes that could be studied as future therapeutic targets for ET patients.
Supplementation with bioactive compounds capable of regulating energy homeostasis is a promising strategy to manage obesity. Here, we have screened the ability of different phenolic compounds ...(myricetin, kaempferol, naringin, hesperidin, apigenin, luteolin, resveratrol, curcumin, and epicatechin) and phenolic acids (
-coumaric, ellagic, ferulic, gallic, and vanillic acids) regulating
fat accumulation. Resveratrol exhibited the strongest lipid-reducing activity, which was accompanied by the improvement of lifespan, oxidative stress, and aging, without affecting worm development. Whole-genome expression microarrays demonstrated that resveratrol affected fat mobilization, fatty acid metabolism, and unfolded protein response of the endoplasmic reticulum (UPR
), mimicking the response to calorie restriction. Apigenin induced the oxidative stress response and lipid mobilization, while vanillic acid affected the unfolded-protein response in ER. In summary, our data demonstrates that phenolic compounds exert a lipid-reducing activity in
through different biological processes and signaling pathways, including those related with lipid mobilization and fatty acid metabolism, oxidative stress, aging, and UPR-ER response. These findings open the door to the possibility of combining them in order to achieve complementary activity against obesity-related disorders.
Chromosomal translocations in tumors frequently produce fusion genes coding for chimeric proteins with a key role in oncogenesis. Recent reports described a BCR-JAK2 fusion gene in fatal chronic and ...acute myeloid leukemia, but the functional behavior of the chimeric protein remains uncharacterized. We used fluorescence in situ hybridization and reverse transcription polymerase chain reaction (RT-PCR) assays to describe a BCR-JAK2 fusion gene from a patient with acute lymphoblastic leukemia. The patient has been in complete remission for six years following treatment and autologous transplantation, and minimal residual disease was monitored by real-time RT-PCR. BCR-JAK2 codes for a protein containing the BCR oligomerization domain fused to the JAK2 tyrosine-kinase domain. In vitro analysis of transfected cells showed that BCR-JAK2 is located in the cytoplasm. Transduction of hematopoietic Ba/F3 cells with retroviral vectors carrying BCR-JAK2 induced IL-3-independent cell growth, constitutive activation of the chimeric protein as well as STAT5 phosphorylation and translocation to the nuclei, where Bcl-xL gene expression was elicited. Primary mouse progenitor cells transduced with BCR-JAK2 also showed increased proliferation and survival. Treatment with the JAK2 inhibitor TG101209 abrogated BCR-JAK2 and STAT5 phosphorylation, decreased Bcl-xL expression and triggered apoptosis of transformed Ba/F3 cells. Therefore, BCR-JAK2 is a novel tyrosine-kinase with transforming activity. It deregulates growth factor-dependent proliferation and cell survival, which can be abrogated by the TG101209 inhibitor. Moreover, transformed Ba/F3 cells developed tumors when injected subcutaneously into nude mice, thus proving the tumorigenic capacity of BCR-JAK2 in vivo. Together these findings suggest that adult and pediatric patients with BCR-ABL-negative leukemia and JAK2 overexpression may benefit from targeted therapies.
Molting is an essential developmental process in Caenorhabditis elegans. However, the study of molting in the worm has been limited by the lack of automated techniques that allow monitoring the ...process in a simple way. In 2015, Olmedo et al. published an automated method to monitor the timing of each larval stage and molt in C. elegans using bioluminescence. This new method has greatly contributed to the study of molting in this organism but requires the use of a high-sensitivity luminometer, which many laboratories do not have. We have adapted the method to a conventional luminometer, so that it can be used by most laboratories that work with C. elegans and do not have high-sensitivity equipment.•A customization of a method to study molting in C. elegans using a conventional luminometer instead of a high-sensitivity one.•This adaptation allows most laboratories to use their routine luminometers to study molting in C. elegans.•Although the use of a high-sensitivity luminometer, as proposed by Olmedo et al., remains the gold standard for studying molting, this adaptation is suitable for studying significant differences in molting and the duration of larval stages between different strains of C. elegans.
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•Origanum vulgare L. hydroalcoholic extract shows antioxidant activity in vitro and in vivo.•Oral formulation of oregano preserves antioxidant activity from gastrointestinal ...digestion.•Encapsulation improve antioxidant activity of O. vulgare in C. elegans.•Rosmarinic acid and 3,4-dihydroxybenzoic acid seem to be the major bioactive compounds of O. vulgare, even after digestion.
Aging-related diseases can be triggered by multiple factors such as oxidative stress. Oxidative stress is an imbalance between free radicals and antioxidants, so today, compounds capable of reducing or neutralizing free radicals are being studied for a therapeutic use. Origanum vulgare L. is a traditional medicinal plant used for a wide number of health problems due to its antimicrobial, carminative and antioxidant activities. However, when administered orally, gastrointestinal digestion can modify some of therapeutical properties. To avoid this, two different solid oral formulations have been designed for an O. vulgare extract evaluating their antioxidant behaviours in vitro and in vivo after a simulation of gastrointestinal digestion. The results showed that the divided powder has a lower antioxidant activity both in vitro and in vivo than the encapsulated extract. The quantitative difference of polyphenols found on HPLC-DAD (especially luteolin, apigenin and caffeic acid) may explain the differences in pharmacological activity. Thus, we propose that the best form to administrate O. vulgare extracts to maintain the antioxidant properties is the encapsulated form, that is, two capsules of 250 mg of a hydroalcoholic extract of O. vulgare with a minimum of 33 % of rosmarinic acid as a daily dose.
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The aim of this work was to prepare and evaluate cyclodextrins-modified poly(anhydride) nanoparticles to enhance the oral administration of glibenclamide. A conjugate polymer was ...synthesized by incorporating hydroxypropyl-β-cyclodextrin to the backbone of poly(methylvinyl ether-co-maleic anhydride) via Steglich reaction. The degree of substitution of anhydride rings by cyclodextrins molecules was calculated to be 4.9% using H-NMR spectroscopy. A central composite design of experiments was used to optimize the preparative process. Under the optimal conditions, nanoparticles displayed a size of about 170 nm, a surface charge of −47 mV and a drug loading of 69 µg GB/mg. X-ray diffraction studies confirmed the loss of the crystalline structure of GB due to its dispersion into the nanoparticles, either included into cyclodextrin cavities or entrapped in the polymer chains. Glibenclamide was mainly release by Fickian-diffusion in simulated intestinal fluid. GB-loaded nanoparticles produced a hypolipidemic effect over C. elegans N2 wild-type and daf-2 mutant. The action mechanism included daf-2 and daf-28 genes, both implicated in the insulin signaling pathway of C. elegans. In summary, the covalent linkage of cyclodextrin to the poly(anhydride) backbone could be an interesting strategy to prepare nanoparticles for the oral administration of glibenclamide.
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