Epigenetic regulation exerted by Caliphruria subedentata and galantamine: an in vitro and in silico approach for mimic Alzheimer's disease.

At the interface between genes and environment, epigenetic mechanisms, including DNA methylation and histone modification, regulate neurogenic processes such as differentiation, proliferation, and maturation of neural stem cells. However, these mechanisms are altered in Alzheimer's disease (AD), a neurodegenerative condition that mainly affects older adults. Since epigenetic mechanisms are known to be reversible, a number of molecules from natural sources are being studied as epigenetic regulators in AD. Recently, in vitro and in silico studies have shown that C. subedentata and its alkaloids modulated neurotoxicity. However, studies exploring the epigenetic activity of these alkaloids are limited. We conducted a set of bioassays to evaluate neuronal differentiation and the sensitivity of undifferentiated SH-SY5 cells against a neurotoxic stimulus. In addition, we analyzed the methylation profiles in genes such as APP, PSI, and BACE1 due to their role in amyloid processing. Docking and molecular dynamic analysis were used to explore the effect exerted by C. subedentata alkaloids on the regulation of histone deacetylases (HDAC2, HDAC3 and HDAC7). The results demonstrated that C. subedentata and galantamine induce neuronal differentiation and protect the undifferentiated SH-SY5Y cells against Aß(1-42)-induced neurotoxicity. The methylation profiles of the studied genes show no statistically significant differences between C. subedentata, galantamine. However, these findings should be interpreted with caution, since small changes in methylation promoters in the brain could not be easily detected. Results from in silico approaches describe for the first time the potential promissing epigenetic effects of galantamine by regulating HDAC3 and HDAC7 modification.Communicated by Ramaswamy H. Sarma.

The hsa-miR-516a-5p and hsa-miR-516b-5p microRNAs reduce the migration and invasion on T98G glioblastoma cell line.

microRNAs (miRNAs) are involved in numerous functions and processes in the brain and other organs through the regulation of gene and protein expression. miRNA dysregulation is associated with the development of several diseases, including the brain and Central Nervous System cancer (CNS). The hsa-miR-516a-5p and hsa-miR-516b-5p are involved in proliferation, migration, and invasion in different tumor models, but their antitumor effect has not been evaluated in cancer of CNS. Therefore, we aimed to assess the effect of the miRNAs hsa-miR-516a-5p and miRNA hsa-miR-516b-5p on the Glioblastoma cell line (T98G). We used synthetic miRNA mimics to induce the overexpression of both miRNAs in the cell line, which was corroborated by RT-qPCR. Next, we evaluated the effect on proliferation, migration, and invasion using the CyQuant direct kit, ThinCert ™ inserts and invasion BioCoat ™ Matrigel® Invasion Chambers. We found upregulation of these miRNAs induced significant changes on the migration and invasion processes of T98G cells, but not affected the proliferation rate. These results suggest that both microRNAs could be playing an important role in the control of tumor progression towards metastasis. The bioinformatics analysis showed that target genes for these miRNAs are involved in different biological processes such as in cell adhesion molecule binding and cell junction disassembly, which are important for cancer progression. Further studies and experimental validation are needed to identify the genes regulated by microRNAs.

Mitochondrial Dysfunction in Intensive Care Unit Patients.

BACKGROUND: In patients admitted to the Intensive Care Unit (ICU), mortality is high due to multiple organ damage. Mitochondrial dysfunction and impaired oxygen consumption, as causative mechanisms, play a significant role in reducing the activity of immune cells in sepsis, resulting in the progression of the multiple organ dysfunction syndromes (MODS). The evaluation of mitochondrial function in critical care patients in the immune cells, especially in lymphocytes, could reveal the target point that determines mitochondrial failure. OBJECTIVE: To find the relationship between mitochondrial reactive oxygen species production (mROS), mitochondrial membrane potential (ΔΨm), and mitochondrial oxygen consumption (mVO2) in peripheral plasma lymphocytes collected from ICU patients. We also compared these three characteristic mitochondrial functions with C-reactive protein (CRP), serum lactate, and central venous saturation (SvO2) that would enable the prediction of the ultimate outcome. METHODS: Isolated lymphocytes from 54 critical care patients with SIRS by sepsis and non-sepsis etiologies were analyzed with flow cytometry by staining with dihydroethidium and JC-1, measuring mROS, ΔΨm, and mVO2. Clinical variables, such as serum lactate (mmol/L) and C-reactive protein (mg/L) from peripheral blood, were measured in the first 24 hours of admission. A confounding analysis was performed using logistic regression, and a p-value of <0.05 was considered statistically significant. RESULTS: It has been confirmed that there is a drastic increase in reactive oxygen species (ROS) and mVO2 in critically ill patients immediately after exposure to the insult pathogen-associated molecular pattern /damageassociated molecular pattern (PAMPS/DAMPS) and continued for the first 24 hours thereafter. The results showed no significant alterations in the mitochondrial membrane potential (ΔΨm) compared with the lymphocytes in controls. A significant correlation between CRP and SvO2 and a strong positive relationship between CRP, values above 3 mg/l, and white blood cells were observed. CONCLUSION: Lymphocytes from patients with SIRS displayed higher mitochondrial respiratory capacities and reactive oxygen species production compared with controls. Clinical markers of inflammation indirectly evaluate the mitochondrial function, most of which have been validated in a clinical setting.

Effect of 6-Shogaol on the Glucose Uptake and Survival of HT1080 Fibrosarcoma Cells.

Ginger is a plant that is native to southern China. In the last decade and research on the components of ginger has significantly increased; of these components, 6-shogaol exhibits the greatest potential antitumor capacity. However, the molecular mechanism through which 6-shogaol exerts its effects has not yet been elucidated. In this study, the effect of 6-shogaol on tumor cells that were derived from human fibrosarcoma (HT1080) was evaluated. Cell viability was determined by a (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) MTT assay testing different concentrations of 6-shogaol (2.5-150 µM). Subsequently, the effect of 6-shogaol on reactive oxygen species (ROS) production, glucose uptake, and protein expression of the signaling pathway phosphatase and tensin homolog/ protein kinase B /mammalian target of rapamycin (PTEN/Akt/mTOR) was measured. 6-Shogaol reduced the viability of the tumor cells and caused an increase in ROS production, which was attenuated with the addition of N-acetylcysteine, and the recovery of cell viability was observed. The increase in ROS production in response to 6-shogaol was associated with cell death. Similarly, glucose uptake decreased with incremental concentrations of 6-shogaol, and an increase in the expression of mTOR-p and Akt-p proteins was observed; PTEN was active in all the treatments with 6-shogaol. Thus, the results suggest that cells activate uncontrolled signaling pathways, such as phosphoinositide 3-kinase (PI3K)/Akt/mTOR, among other alternative mechanisms of metabolic modulation and of survival in order to counteract the pro-oxidant effect of 6-shogaol and the decrease in glucose uptake. Interestingly, a differential response was observed when non-cancerous cells were treated with 6-shogaol.

Melatonin restrains angiogenic factors in triple-negative breast cancer by targeting miR-152-3p: In vivo and in vitro studies.

AIMS: Breast cancer represents the second most prevalent tumor-related cause of death among women. Although studies have already been published regarding the association between breast tumors and miRNAs, this field remains unclear. MicroRNAs (miRNAs) are defined as non-coding RNA molecules, and are known to be involved in cell pathways through the regulation of gene expression. Melatonin can regulate miRNAs and genes related with angiogenesis. This hormone is produced naturally by the pineal gland and presents several antitumor effects. The aim of this study was to understand the action of melatonin in the regulation of miRNA-152-3p in vivo and in vitro. MAIN METHODS: In order to standardize the melatonin treatment in the MDA-MB-468 cells, we carried out the cell viability assay at different concentrations. PCR Array plates were used to identify the differentiated expression of miRNAs after the treatment with melatonin. The relative quantification of the target gene expression (IGF-IR, HIF-1α and VEGF) was performed by real-time PCR. For the tumor development, MDA-MB-468 cells were implanted in female BALB/c mice, and treated or not treated with melatonin. Moreover, the quantification of the target genes protein expression was performed by immunocytochemistry and immunohistochemistry. KEY FINDINGS: Relative quantification shows that the melatonin treatment increases the gene expression of miR-152-3p and the target genes, and decreased protein levels of the genes both in vitro and in vivo. SIGNIFICANCE: Our results confirm the action of melatonin on the miR-152-3p regulation known to be involved in the progression of breast cancer.

Exploration of the Acetylcholinesterase Inhibitory Activity of Some Alkaloids from Amaryllidaceae Family by Molecular Docking In Silico.

Alzheimer's disease (AD) is a progressive condition, where dementia symptoms gradually worsen. Biochemically the disease is characterized by the presence of neuritic plaques, neurofibrillary tangles, in addition to cholinergic dysfunction in the central nervous system. The role of the cholinergic neurotransmission in AD is the basis of the widely accepted cholinergic hypothesis. Some of the most relevant therapies for the treatment of the disease are based on the acetylcholinesterase (AChE) inhibitor activity; however, these therapies are not effective to stop the disease progression, but only can temporarily slow down the worsening of dementia symptoms, and improve quality of life of patients and their caregivers. In recent years, plant alkaloids extracted from Amaryllidaceae family have received great attention due to the well-known anti cholinergic activity. In this context, the purpose of this study was to apply the docking molecular in sílico analysis aiming to examine the recombinant human AChE enzyme (rhAChE) inhibitory activity displayed by different alkaloids from Amaryllidaceae family. Overall, the present results support the idea that alkaloids reported in this research are capable of interacting with rhAChE-binding sites.

Galanthamine decreases genotoxicity and cell death induced by ß-amyloid peptide in SH-SY5Y cell line.

Biochemically, Alzheimers disease (AD) is characterized by the presence of abnormal deposition of beta amyloid peptide (Aß(1-42)), which is generated by proteolytic processing from its precursor, the amyloid precursor protein (APP) in a non-physiological pathway. The presence of Aß(1-42) in the brain is strongly correlated with cognitive impairment, cholinergic deficiency, bioenergetics disruption, cell death and DNA damage. Galanthamine is an acetylcholinesterase inhibitor (AChEI) used to symptomatic treatment of Alzheimers disease (AD). Several studies have showed that galanthamine has antioxidant properties, anti-apoptotic action and also promotes neurogenesis; however, it is unknown whether galanthamine may present protection mechanisms against Aß(1-42)-induced genomic instability. To understand the mechanisms of this neuroprotection, we studied the effects of galanthamine on the cell toxicity and DNA strand breaks induced by Aß(1-42) using a set of biomarkers such as clonogenic assay, cytokinesis block micronucleus cytome (CBNM-cyt) and comet assay. The results showed that galanthamine treatments were capable to significantly reduce the Aß(1-42)-induced cytotoxicity and genotoxicity. In conclusion, this study demonstrated that in addition to inhibition of acetylcholinesterase (AChE), galanthamine exerts antigenotoxic properties. This relevant property of galanthamine is worthwhile exploring further which may improve the development of new diseases-modifying agents.