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As life expectancy increases, the number of people affected by cancer is increasing. The available drugs still cause several adverse reactions, and it is important to look for less toxic drugs that act on resistant cancers. The present study evaluated the antitumor potential of acetogenins. Through a literature review, 44 acetogenins isolated from Annona muricata were selected and subjected to in silico studies to predict the physicochemical properties, pharmacokinetics (Preadmet and Admet lab), toxicity (Preadmet and Protox II) and molecular docking in caspase 3 (DockThor). For muricatacin, a literature review was carried out for antitumor activity and cytotoxicity. Only muricatacin met all physicochemical criteria, while all compounds showed high cutaneous and intestinal absorption (HIA), moderate permeability in Madin-Darby canine kidney and Caco2 cells, strongly bound plasma proteins, freely crossed the blood-brain barrier, inhibited CYP2C19, CYP2C9 and CYP3A4 and have an affinity for CYP3A4, being metabolized by it, an undesirable characteristic for antitumor drugs. All compounds were toxic in at least one model, while compound 28 was not carcinogenic in rats and mice. Compounds 13, 14, 15, 16, 17 and 28 were selected for molecular docking into Caspase 3. Docking showed hydrophobic interactions, hydrogen and covalent bonds performed to maintain the stability of caspase 3, and cis-uvariamicin IV stood out more through the energies and chemical bonds of this parameter. The chloroform fraction from the methanolic extract of the seeds showed activity against triple-negative breast cancer, both in vitro and in vivo , and only muricatacin has studies in which the antitumor activity was evaluated in vitro and showed to be very promising. In summary, muricatacin and cis-uvariamicin IV appear to be very promising as antitumors, especially cis-uvariamicin IV., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Fallon Adido, Silva Chagas, Ferreira, Carmo Bastos and Dolabela.)

From Eleutherine plicata , naphthoquinones, isoeleutherine, and eleutherol were isolated, and previous studies have reported the antioxidant activity of these metabolites. The present work evaluated the role of oxidative changes in mice infected with Plasmodium berghei and treated with E. plicata extract, fraction, and isolated compounds, as well as to verify possible oxidative changes induced by these treatments. E. plicata extracts were prepared from powder from the bulbs, which were submitted to maceration with ethanol, yielding the extract (EEEp), which was fractionated under reflux, and the dichloromethane fraction (FDMEp) was submitted for further fractionation, leading to the isolation of isoeleutherine, eleutherine, and eleutherol. The antimalarial activity was examined using the suppressive test, evaluating the following parameters of oxidative stress: trolox equivalent antioxidant capacity (TEAC), thiobarbituric acid reactive substances (TBARS), and reduced glutathione (GSH). Furthermore, the molecular docking of naphthoquinones, eleutherol, eleutherine, and isoeleutherine interactions with antioxidant defense enzymes was investigated, which was favorable for the formation of the receptor-ligand complex, according to the re-rank score values. Eleutherine and isoeleutherine are the ones with the lowest binding energy for catalase (CAT), glutathione reductase (GR), and glutathione peroxidase (GPx1), showing themselves as possible targets of these molecules in the involvement of redox balance. Data from the present study showed that treatments with E. plicata stimulated an increase in antioxidant capacity and a reduction in oxidative stress in mice infected with P. berghei , with naphthoquinones being responsible for reducing oxidative changes and disease severity.

The alkaloids isolated from Zanthoxylum rhoifolium have demonstrated great pharmacological potential; however, the toxic profiles of these extracts and fractions are still not well elucidated. This study evaluated the toxicity of the ethanol extract (EEZR) and neutral (FNZR) and alkaloid (FAZR) fractions. Chemical characterization was performed by chromatographic methods: thin-layer chromatography (TLC) and high-performance liquid chromatography coupled with diode array detection (HPLC-DAD). The cytotoxicity of the samples was evaluated in human hepatocellular carcinoma (HepG2) cells using the cell viability method (MTT) and mutagenicity by the Allium cepa assay (ACA). Alkaloids isolated from the species were selected for toxicity prediction using preADMET and PROTOX. The molecular docking of the topoisomerase II protein (TOPOII) was used to investigate the mechanism of cell damage. In the EEZR, FNZR, and FAZR, the presence of alkaloids was detected in TCL and HPLC-DAD analyses. These samples showed a 50% inhibitory concentration (IC 50 ) greater than 400 μg/mL in HepG2 cells. In ACA, time- and concentration-dependent changes were observed, with a significant reduction in the mitotic index and an increase in chromosomal aberrations for all samples. Nuclear sprouts and a micronucleus of the positive control (PC) were observed at 10 µg/mL and in the FAZR at 30 µg/mL; a chromosomal bridge in FNZR was observed at 105 µg/mL, CP at a concentration of 40 µg/mL, and nuclear bud and mitotic abnormalities in the EEZR were observed at 170 µg/mL. The alkaloids with a benzophenanthridine were selected for the in silico study, as structural alterations demonstrated certain toxic effects. Molecular docking with topo II demonstrated that all alkaloids bind to the protein. In summary, the fractionation of Z. rhoifolium did not interfere with toxicity; it seems that alkaloids with a benzophenanthridine nucleus may be involved in this toxicity.

This study evaluated the genotoxicity of Ethanol Extract (EEEp), Dichloromethane Fraction (FDCMEp) and isoeleutherin isolated from Eleutherine plicata , using the micronucleus test and the impact of structural alterations on toxicity and molecular docking (topoisomerase II and DNA complex). The extract was obtained by maceration and fractionation in a chromatography column. The genotoxicity was evaluated by the micronucleus test in human hepatoma cells (HepG2). Isoeleutherin was the starting molecule in the search for analogues by structural similarity, using the ZINC and e-Molecules databases. Isoeleutherin and analogues were subjected to in silico toxicity prediction, and compounds free of toxicological risks (CP13, CP14, CP17 and isoeleutherin) were selected for molecular docking in Topoisomerase II (PDB: 1ZXM). In the micronucleus test, isoeleutherin was less genotoxic. Among the 22 isoeleutherin analogues there were variations in the toxicity profile. Molecular docking studies showed that the compounds have good complementarity in the active site with important hydrogens bonds. Therefore, the structural changes of isoeleutherin led to the obtaining of a molecule with a lower mutagenic potential, and the CP13 can be considered a prototype compound for the development of new molecules with pharmacological potential.

Cancer is a multifactorial organic dysfunction for which great efforts are being devoted in searching for new treatments and therapeutic adjuvants. Annona muricata is a fruit that has promising activity against several types of cancer, as it contains acetogenins, the metabolite group associated with this action. Thus, the objective of this study was to evaluate, in experimental models, the toxic behavior of an extract and fraction rich in acetogenins from A. muricata seeds and study the acetogenin, Annonacin, in silico. Phytochemical characterization was made by thin layer chromatography, spectroscopy in the infrared region and nuclear magnetic resonance. Toxicity was evaluated by tests of Allium cepa and Artemia salina , and in silico studies using the SwissDock servers DockThor, PharmMapper, ADMETLab, PreADME, Osiris and ProTox. The extract and fraction showed genotoxic activity against meristematic cells of A. cepa , reducing the mitotic index; however, the extract produced great deleterious effects on the system, even causing cell necrosis. In A. Saline, the extract was more toxic than the fraction, but both samples were considered toxic. Annonacin was effectively linked to complex I, and presented different activities regarding toxicity. Thus, the results of this study are promising, highlighting the anticancer potential of acetogenins.

Polycystic kidney disease (PKD), also known as autosomal dominant polycystic kidney disease (ADPKD) is a genetically heterogeneous condition characterized by cysts in renal parenchyma. It is the most prevalent inherited disease of domestic cats. MicroRNAs (miRNAs or ncRNA) are short, noncoding, single-stranded RNAs that may induce PKD cytogenesis by affecting numerous targets genes as well as by directly regulating PKD gene expression. We compared the relative expression profile of miR-20a, -192, -365, -15b-5p, and -16-5p from plasma and serum samples of nine domestic cats with PKD1 mutation, detected by polymerase chain reaction (PCR), and a control group (n = 10). Blood samples from cats with PKD1 mutation provide similar concentrations of microRNAs either from plasma or serum. Serum miR-20a is upregulated in PKD group with p < 0.005; Roc curve analysis showed an AUC of 90,1% with a cut-off value sensitivity of 77.8% and specificity of 100%. This data provides important information regarding renal miRNA expression in peripheral blood sampling., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Scalon et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at a post-transcriptional level by silencing targeted messenger RNA (mRNA). Most studies concerning miRNA expression use solid tissue samples. However, circulating miRNAs from different body fluids have recently emerged as diagnostic and prognostic molecules, given that they hold informative value and have increased stability in cell-free form. Blood sampling of cats can be challenging given their small body size and because they often experience distress when handled. We quantified miR-20a, -192, -365, -15b-5p, and -16-5p from plasma and serum samples of 10 healthy domestic cats. Our RT-rtPCR procedure used 100 µL of either plasma or serum samples as sources of biomarker molecules. However, serum provided higher amounts of miRNA than plasma samples, with a p <  0.0001 for miR-20a and p <  0.0002 for miR-16-5p.

Stroke is considered one of the leading causes of death worldwide. The treatment is limited; however, the Brazilian flora has a great source of natural products with therapeutic potentials. Studies with the medicinal plant Polygala sabulosa W. Bennett provided evidence for its use as an anti-inflammatory and neuroprotective drug. In the case of ischemic stroke due to lack of oxygen, both acute and chronic inflammatory processes are activated. Thus, we hypothesized that P. sabulosa (HEPs) has the potential to treat the motor and cognitive deficits generated by ischemic stroke. Male mice were subjected to global ischemia for 60 min, followed by reperfusion and orally treated with HEPs (100 mg/kg in saline + 3% tween 20) twice a day (12 h apart) for 48 h starting 3 h after surgery. Motor skills were assessed using grip force and open field tasks. Hippocampi were then collected for mRNA quantification of the cytokines IL-1-β and TNF-α levels. After 48 h of acute treatment, spatial reference memory was evaluated in a Morris water maze test for another group of animals. We show that HEPs treatment significantly prevented motor weakness induced by ischemia. Brain infarct area was reduced by 22.25% with downregulation of the levels of IL-1β and TNF-α mRNA. Learning performance and memory ability on Morris water maze task were similar to the sham group. Our data demonstrates the neuroprotective properties of HEPs through its anti-inflammatory activities, which prevent motor and cognitive impairments, suggesting that HEPs may be an effective therapy for ischemic stroke.

The flow of gene expression or "The central dogma of molecular biology": DNA - RNA - protein, proposed by Watson & Crick sixty years ago, is a tightly controlled cell process. In the middle of this journey, the mRNA molecule is regulated by "RNA interference" (RNAi), a posttranscriptional gene silencing mechanism. A microRNA is an endogenous short double-stranded RNA that down-regulates hundreds of mRNAs by RNAi, maintaining healthy cell physiology. In contrast, aberrant expressions of microRNAs play a role in Parkinson's disease (PD) pathogenesis. The damage may start at an early period of brain degeneration, in the non-motor or "prodromal" stage, where autonomic, mood and sleep changes are often manifested. REM-sleep behavior disorder (RBD) is the prodromal manifestation with the highest odds for conversion into PD, thereby a valuable phenotype for disease prediction. The present review focuses on microRNAs' role in the pathogenesis of PD and RBD, summarizing the state-of-the-art of these RNA molecules as noninvasive biomarkers for non-motor prodromal (RBD) and early PD., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Parkinson's disease (PD) is a highly complex brain disorder regarding clinical presentation, pathogenesis, and therapeutics. The cardinal motor signs, i.e., rigidity, bradykinesia, and unilateral tremors, arise in consequence of a progressive neuron death during the prodromal phase. Although multiple transmission systems are involved in disease neurobiology, patients will cross the line between the prodromal and early stage of diagnosed PD when they had lost half of the dopaminergic nigrostriatal cells. As the neurons continue to die ascending the neuroaxis, patients will face a more disabling disease with motor and nonmotor signs. Shedding light on molecular mechanisms of neuron death is an urgent need for understanding PD pathogenesis and projecting therapeutics. This work examined the expression of microRNAs in the striatum of parkinsonian rats chronically exposed to rotenone (2.5 mg/Kg, i.p., daily for 10 days). Rotenone caused motor deficits, the loss of TH(+) cells in the nigrostriatal pathway, and a marked microgliosis. This parkinsonian rat striatum was examined at 26 days after the last rotenone injection, for quantification of microRNAs, miR-7, miR-34a, miR-26a, miR-132, miR-382, and Let7a, by qPCR. Parkinsonian rats presented a significant increase in miR-26a and miR-34a (1.5 and 2.2 fold, respectively, P < 0.05), while miR-7 (0.5 fold, P < 0.05) and Let7a were downregulated. This work reports for first time microRNAs aberrantly expressed in the striatum of rotenone-induced parkinsonian rats, suggesting that this dysregulation may contribute to PD pathogenesis. Beyond revealing new clues of neurodegeneration, our findings might prime further studies targeting miRNAs for neuroprotection or even for diagnosis proposal.

Background and Objectives: Disease evolution depends in part on the source of transplanted cells. Therefore, we compared outcomes after allogeneic bone marrow (BM) and peripheral blood stem cell (PBSC) transplantation in patients who underwent transplant at Hospital das Clinicas of the Federal University of Minas Gerais, Brazil., Patients and Methods: We studied 364 patients who received allogeneic BM (n = 142) or PBSC transplantation (n = 222) between July 1995 and May 2005. The median age of the patients was 31 years (range, 3.1-58 years). Chronic myeloid leukemia was the predominant diagnosis (41.2%). A conditioning regimen with cyclosphosphamide and busulfan was used in 79.4% (n = 289) and graft-versus-host disease (GVHD) prophylaxis was cyclosporine/methotrexate in 95.9% (n = 349) of cases., Results: The patients in the PBSC group had faster neutrophil (P < .001) and platelet engraftment (P = .03) but increased rates of acute GVHD (P < .001) vs. those in the BM group. There was no significant difference between the groups in chronic GVHD, transplant-related mortality, relapse and survival rates., Conclusions: Although allogeneic PBSC transplant results in a faster hematopoietic engraftment, there was an increase in acute GVHD. There was no clear benefit in relapse rate and no evidence that transplantation with PBSC benefits patient survival in our institution.

It was shown that adrenergic drugs, which increase the intracellular levels of cAMP, inhibit the rosette formation by T-lymphocytes, but stimulate the rosettes produced by B-lymphocytes. Cholinergic drugs, which increase the levels of cGMP, on the contrary, stimulate the formation of rosettes by T-lymphocytes but inhibit those produced by B-lymphocytes.

Studies were carried out with the leukocyte migration inhibition tests using soluble and particulate antigens (PPD, somatic antigens of T. cruzi, M. bovis (BCG) and leukocytes from patients sensitized to PPD and patients with chronic Chagas' disease. The results obtained showed that the stimulatory capacity of particulate antigens are greater than that of soluble antigens.