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1.
EMBO J ; 43(4): 533-567, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38316990

RESUMO

The phospholipid and free fatty acid (FFA) composition of neuronal membranes plays a crucial role in learning and memory, but the mechanisms through which neuronal activity affects the brain's lipid landscape remain largely unexplored. The levels of saturated FFAs, particularly of myristic acid (C14:0), strongly increase during neuronal stimulation and memory acquisition, suggesting the involvement of phospholipase A1 (PLA1) activity in synaptic plasticity. Here, we show that genetic ablation of the PLA1 isoform DDHD2 in mice dramatically reduces saturated FFA responses to memory acquisition across the brain. Furthermore, DDHD2 loss also decreases memory performance in reward-based learning and spatial memory models prior to the development of neuromuscular deficits that mirror human spastic paraplegia. Via pulldown-mass spectrometry analyses, we find that DDHD2 binds to the key synaptic protein STXBP1. Using STXBP1/2 knockout neurosecretory cells and a haploinsufficient STXBP1+/- mouse model of human early infantile encephalopathy associated with intellectual disability and motor dysfunction, we show that STXBP1 controls targeting of DDHD2 to the plasma membrane and generation of saturated FFAs in the brain. These findings suggest key roles for DDHD2 and STXBP1 in lipid metabolism and in the processes of synaptic plasticity, learning, and memory.


Assuntos
Ácidos Graxos não Esterificados , Memória de Longo Prazo , Proteínas Munc18 , Fosfolipases , Animais , Camundongos , Encéfalo/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Memória/fisiologia , Proteínas Munc18/genética , Fosfolipases/genética
2.
Heliyon ; 10(1): e23553, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38187226

RESUMO

Background: It is well-established that specific herbal plants contain natural active ingredients that have demonstrated anti-cancer potential. Therefore, they are considered highly beneficial as a potential adjuvant, alternative or complementary agent in anti-cancer therapy. However, the low chemical stability and limited bioavailability of 3, 3'-Diindolylmethane (DIM), a plant-derived compound used in clinical settings, limit its therapeutic applications. To overcome this challenge, researchers have focused on developing innovative approaches to improve DIM's biological activity, such as utilizing nanoformulations. Here, we investigated the potential benefits of coating DIM nanoparticles (DIM-NPs) with PEG/chitosan in the treatment of breast cancer. Our results demonstrate the molecular mechanism underlying the activity of DIM-NPs, highlighting their potential as an effective therapeutic strategy for breast cancer treatment. Methods: DIM-PLGA-PEG/chitosan NPs were synthesised and characterised using dynamic light scattering (DLS) and evaluated the impact of these NPs on two breast cancer cell models. Results: DIM-NPs had an average diameter of 102.3 nm and a PDI of 0.182. When treated with DIM-NPs for 48 h, both MCF7 and MDA-MB-231 cells displayed cytotoxicity at a concentration of 6.25 g/mL compared to untreated cells. Furthermore, in MDA-MB-231 cells, treatment with 2.5 µg/mL of DIM-NPs resulted in a significant decrease in cell migration, propagation, and angiogenesis which was further enhanced at 10 µg/mL. In chicken embryos, treatment with 5 µg/mL of DIM-NPs on day 2 led to a significant reduction in angiogenesis. Furthermore, this treatment induced cell death through a regulatory pathway involving the upregulation of Bax and p53, as well as the downregulation of Bcl-2. These results were supported by in-silico analysis of DIM's binding affinity to key proteins involved in this pathway, namely Bax, Bcl-2, and p53. Conclusion: Our findings show that DIM-NPs induces apoptosis, inhibit migration, and reduce angiogenesis in breast cancer. However, further research using a preclinical cancer model may be necessary to determine the pharmacokinetics of DIM-NPs and ensure their safety and efficacy in vivo.

3.
Artif Cells Nanomed Biotechnol ; 51(1): 361-370, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37524306

RESUMO

BACKGROUND: Curcumin has been used in the treatment of several diseases; however, its low pharmacologic profile reduces its therapeutic use. Towards improving its biological activity, nanoformulations have emerged. Thus, we aimed to determine whether curcumin nanoparticles (Cur-NPs) coated with PEG/chitosan improve the treatment of liver cancer (LC) cells and underpin the molecular mechanisms underlying their anti-cancer activity. METHODS: Cur-NPs were synthesised in the form of Cur-PLGA-PEG/chitosan NPs. The effect of Cur-NPs was assessed in HepG2 and Huh 7 LC cells and THLE-2 normal liver cells. RESULTS: The size of synthesised Cur-NPS was determined in the standard range of 141.2 ± 47.5 nm. Compared to THLE-2 cells, LC cells treated with Cur-NPs exerted cytotoxicity at 6.25 µg/mL after 48h. Treatment of HepG-2 cells with 2.5 µg/mL of Cur-NPs inhibited cell migration and this inhibition was augmented at 10 µg/mL (p < 0.001). Treatment of chicken embryo with 5 µg/mL Cur-NPs reduced angiogenesis (p < 0.001) of 4-day-old embryos. The nanoformulation upregulated Bax and p53 and downregulated Bcl-2 in a concentration-dependent manner and subsequently induce apoptosis in HepG-2 cells. CONCLUSION: Treatment of LC cells with Cur-NPs decreased cell proliferation, migration, and angiogenesis, and induced cell death by promoting the proapoptotic pathway.


Curcumin nanoparticles (Cur-NPs) increase the anticancer efficiency of Curcumin against liver cancer cells.Cur-NPs induce apoptotic cell death of Liver cancer cells.Cur-NPs have ant-angiogenesis and metastasis effect.


Assuntos
Quitosana , Curcumina , Neoplasias Hepáticas , Nanopartículas , Embrião de Galinha , Animais , Curcumina/farmacologia , Curcumina/uso terapêutico , Linhagem Celular Tumoral , Quitosana/farmacologia , Apoptose , Neoplasias Hepáticas/tratamento farmacológico
4.
EMBO J ; 42(13): e112095, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37226896

RESUMO

The unique nerve terminal targeting of botulinum neurotoxin type A (BoNT/A) is due to its capacity to bind two receptors on the neuronal plasma membrane: polysialoganglioside (PSG) and synaptic vesicle glycoprotein 2 (SV2). Whether and how PSGs and SV2 may coordinate other proteins for BoNT/A recruitment and internalization remains unknown. Here, we demonstrate that the targeted endocytosis of BoNT/A into synaptic vesicles (SVs) requires a tripartite surface nanocluster. Live-cell super-resolution imaging and electron microscopy of catalytically inactivated BoNT/A wildtype and receptor-binding-deficient mutants in cultured hippocampal neurons demonstrated that BoNT/A must bind coincidentally to a PSG and SV2 to target synaptic vesicles. We reveal that BoNT/A simultaneously interacts with a preassembled PSG-synaptotagmin-1 (Syt1) complex and SV2 on the neuronal plasma membrane, facilitating Syt1-SV2 nanoclustering that controls endocytic sorting of the toxin into synaptic vesicles. Syt1 CRISPRi knockdown suppressed BoNT/A- and BoNT/E-induced neurointoxication as quantified by SNAP-25 cleavage, suggesting that this tripartite nanocluster may be a unifying entry point for selected botulinum neurotoxins that hijack this for synaptic vesicle targeting.


Assuntos
Toxinas Botulínicas Tipo A , Toxinas Botulínicas Tipo A/metabolismo , Membrana Celular/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Vesículas Sinápticas/metabolismo , Animais , Ratos
5.
J Virol ; 97(4): e0014423, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37039676

RESUMO

2019 coronavirus disease (COVID-19) is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In addition to respiratory illness, COVID-19 patients exhibit neurological symptoms lasting from weeks to months (long COVID). It is unclear whether these neurological manifestations are due to an infection of brain cells. We found that a small fraction of human induced pluripotent stem cell (iPSC)-derived neurons, but not astrocytes, were naturally susceptible to SARS-CoV-2. Based on the inhibitory effect of blocking antibodies, the infection seemed to depend on the receptor angiotensin-converting enzyme 2 (ACE2), despite very low levels of its expression in neurons. The presence of double-stranded RNA in the cytoplasm (the hallmark of viral replication), abundant synthesis of viral late genes localized throughout infected cells, and an increase in the level of viral RNA in the culture medium (viral release) within the first 48 h of infection suggested that the infection was productive. Productive entry of SARS-CoV-2 requires the fusion of the viral and cellular membranes, which results in the delivery of the viral genome into the cytoplasm of the target cell. The fusion is triggered by proteolytic cleavage of the viral surface spike protein, which can occur at the plasma membrane or from endosomes or lysosomes. We found that SARS-CoV-2 infection of human neurons was insensitive to nafamostat and camostat, which inhibit cellular serine proteases, including transmembrane serine protease 2 (TMPRSS2). Inhibition of cathepsin L also did not significantly block infection. In contrast, the neuronal infection was blocked by apilimod, an inhibitor of phosphatidyl-inositol 5 kinase (PIK5K), which regulates early to late endosome maturation. IMPORTANCE COVID-19 is a disease caused by the coronavirus SARS-CoV-2. Millions of patients display neurological symptoms, including headache, impairment of memory, seizures, and encephalopathy, as well as anatomical abnormalities, such as changes in brain morphology. SARS-CoV-2 infection of the human brain has been documented, but it is unclear whether the observed neurological symptoms are linked to direct brain infection. The mechanism of virus entry into neurons has also not been characterized. Here, we investigated SARS-CoV-2 infection by using a human iPSC-derived neural cell model and found that a small fraction of cortical-like neurons was naturally susceptible to infection. The productive infection was ACE2 dependent and TMPRSS2 independent. We also found that the virus used the late endosomal and lysosomal pathway for cell entry and that the infection could be blocked by apilimod, an inhibitor of cellular PIK5K.


Assuntos
COVID-19 , Células-Tronco Pluripotentes Induzidas , SARS-CoV-2 , Humanos , Enzima de Conversão de Angiotensina 2 , COVID-19/fisiopatologia , Endossomos/metabolismo , Endossomos/virologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Neurônios/metabolismo , Neurônios/virologia , Síndrome de COVID-19 Pós-Aguda/fisiopatologia , Síndrome de COVID-19 Pós-Aguda/virologia , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos , Fosfotransferases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Astrócitos/virologia , Células Cultivadas
6.
Biol Trace Elem Res ; 201(10): 4688-4696, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36602747

RESUMO

This paper presents the synthesis and isolation of a new binuclear complex of yttrium with anthranilic acid (HA). The complex [Y2(HA)6(H2O)4] Cl6.2C2H5OH (C1) was obtained as single crystals that its X-ray analysis revealed its triclinic P-1 space group in addition to anti-prismatic geometry around each of the yttrium ions. In the complex, the anthranilic acid ligands are bidentate, zwitter ionic and neutral, and the yttrium ions' charge is only compensated by six chloride ions. The cytotoxicity of this complex against human breast cancer MDA-MB-231 cells, prostate cancer PC-3 cells, and bladder cancer T-24 cells was evaluated. This yttrium complex displayed more cytotoxic activity against the bladder cancer cells with an IC50 value of 307.7 µg/ml (223 µM). On the other hand, the activities of complex C1 against the MDA-MB-231 and PC-3 cells were less significant respectively with IC50 values of 1097 µg/ml (796 µM) and 921 µg/ml (669 µM).


Assuntos
Antineoplásicos , Neoplasias da Bexiga Urinária , Humanos , Ítrio , Antineoplásicos/química , ortoaminobenzoatos/farmacologia , Linhagem Celular Tumoral
7.
Nat Prod Res ; : 1-10, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36408968

RESUMO

A binuclear La(III) complex {[La2(HA)4(H2O)4(C2H5OH)2Cl2]Cl4 (C1)} with 2-aminobenzoic acid (HA) was prepared from the ligand and heptahydrated lanthanum chloride. The complex was characterised by X-ray crystallography that revealed anti-prismatic geometry around both of the lanthanum. In the complex, the four 2-aminobenzoic acid ligands are zwitter ionic and the two lanthanum(III) ions net charge is only counterbalanced by chloride ions. The complex cytotoxicity was determined against human breast (MDA-MB-231), prostate (PC-3) and bladder (T-24) cancer cells. This complex afforded cytotoxicity towards the T-24 bladder cancer cells with an IC50 value of 383.5 µg/mL (319 µM). In contrary, activities by the lanthanum complex with IC50 values of 1124 µg/mL (934 µM) and 739 µg/mL (614 µM) were, respectively, shown against the MDA-MB-231 and PC-3 cancer cells. This means the complex is more cytotoxic against the T-24 cells, despite that its activity is less compared with activities shown by classical drugs.

8.
Biotechnol Genet Eng Rev ; : 1-22, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36123822

RESUMO

Bacterial co-infections are typically associated with viral respiratory tract infections and pose a significant public health problem around the world. COVID-19 infection damages tissues lining the respiratory track and regulates immune cells/cytokines leading to microbiome dysbiosis and facilitating the area to be colonized by pathogenic bacterial agents. There have been reports of different types of bacterial co-infection in COVID-19 patients. Some of these reports showed despite geographical differences and differences in hospital settings, bacterial co-infections are a major cause of morbidity and mortality in COVID-19 patients. The inappropriate use of antibiotics for bacterial infections, particularly broad-spectrum antibiotics, can also further complicate the infection process, often leading to multi drug resistance, clinical deterioration, poor prognosis, and eventually death. To this end, researchers must establish a new therapeutic approach to control SARS-CoV-2 and the associated microbial coinfections. Hence, the aim of this review is to highlight the bacterial co-infection that has been recorded in COVID-19 patients and the status of antimicrobial resistance associated with the dual infections.

9.
Saudi J Biol Sci ; 29(4): 3040-3050, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35531174

RESUMO

Recent years have reported a rise in the occurrence of gastric ulceration especially among young children and adults. This study investigated the mechanism by which two types of Saudi honey: Alnahal Aljawal honey (Wadi) or Bin Ghaithan honey (Talh) exerted their antiulcer potential in indomethacin-induced gastric ulceration. Four cohorts of rats were used: Group 1; Healthy controls, Group 2; Ulcerative animals, Group 3; Ulcerative + Wadi honey treatment, Group 4; Ulcerative + Talh honey treatment. We profiled the levels of different indicators of oxidative stress including the activities of gastric mucosal glutathione superoxide dismutase (SOD), catalase (CAT), peroxidase (GPx), reduced glutathione (GSH), and lipid peroxidation (measured as malondialdehyde; MDA). CRP content, IL-10, and plasma tumor necrosis factor-α were also evaluated. The stomach was visually examined for macroscopic lesions and using light microscope for histopathological changes in the glandular mucosa. Wadi or Talh honey significantly reduced the ulcer indices, and essentially protected the glandular mucosa from lesions. Wadi or Talh honey also significantly reduced the gastric mucosal concentrations of GPx, SOD and GSH. In addition, the administration of Wadi or Talh honey decreased gastric mucosal plasma TNF-α and MDA, CRP content, and IL-10 levels. In conclusion, Wadi or Talh honey possibly exerted their antiulcer potential via restoring the homeostasis and stabilizing the enzymatic (SOD and GPx) and non-enzymatic (GSH) antioxidants as well as reducing the levels of inflammatory cytokines (TNF-α, CRP content, IL-10 and, NF-κB activity), and inhibiting the lipid peroxidation in the gastric mucosa. Consequently, Wadi or Talh honey may be of beneficial therapy for patients diagnosed with gastric ulceration. Clinical studies need to be conducted to further support these findings.

10.
Molecules ; 27(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35268707

RESUMO

Cisplatin (CISP) is one of the most widely used anti-cancer chemotherapeutic agents with remarkable efficacy against various types of cancers. However, it has been associated with nephrotoxicity amongst other undesirable side effects. Pomegranate (PE) is a potent antioxidant and anti-inflammatory agent effective against cancer, with a superior benefit of not being associated with the common toxicities related to the use of conventional chemotherapeutic agents. However, the application of PE is limited by its reduced solubility and decreased bioavailability. We investigated the potential of a novel nanoparticle (NP) enclosing PE to enhance its solubility and improve its bioavailability, and efficacy to prevent CISP-associated nephrotoxicity in a mice model of Ehrlich solid carcinoma (ESC). All mice were grouped into four cohorts: (I) control, (II) tumor, (III) CISP, and (IV) CISP + PE-NPs. The data obtained demonstrated that PE-NPs was beneficial in potently ameliorating CISP-induced nephrotoxicity in ESC mice. PE-NPs significantly attenuated CISP-induced oxidative stress and lipid peroxidation in the kidney via improving activities of antioxidants (SOD, GSH, and CAT). Additionally, PE-NPs considerably decreased CISP-induced inflammation in the kidney by decreasing the levels of NF-kB, IL-1ß, and TNF-α. Notably, PE-NPs did not assuage the antitumor efficacy of CISP as revealed by histological assessment and tumor weight data. In summary, PE-NPs may be a potent alternative anticancer therapy devoid of nephrotoxicity.


Assuntos
Antineoplásicos , Carcinoma , Nanopartículas , Punica granatum , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/metabolismo , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose , Carcinoma/patologia , Cisplatino/farmacologia , Rim , Camundongos , Estresse Oxidativo
11.
Sci Rep ; 11(1): 13659, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34211018

RESUMO

In this study, two highly thermotolerant and methanol-tolerant lipase-producing bacteria were isolated from cooking oil and they exhibited a high number of catalytic lipase activities recording 18.65 ± 0.68 U/mL and 13.14 ± 0.03 U/mL, respectively. Bacterial isolates were identified according to phenotypic and genotypic 16S rRNA characterization as Kocuria flava ASU5 (MT919305) and Bacillus circulans ASU11 (MT919306). Lipases produced from Kocuria flava ASU5 showed the highest methanol tolerance, recording 98.4% relative activity as well as exhibited high thermostability and alkaline stability. Under the optimum conditions obtained from 3D plots of response surface methodology design, the Kocuria flava ASU5 biocatalyst exhibited an 83.08% yield of biodiesel at optimized reaction variables of, 60 â—‹C, pH value 8 and 1:2 oil/alcohol molar ratios in the reaction mixture. As well as, the obtained results showed the interactions of temperature/methanol were significant effects, whereas this was not noted in the case of temperature/pH and pH/methanol interactions. The obtained amount of biodiesel from cooking oil was 83.08%, which was analyzed by a GC/Ms profile. The produced biodiesel was confirmed by Fourier-transform infrared spectroscopy (FTIR) approaches showing an absorption band at 1743 cm-1, which is recognized for its absorption in the carbonyl group (C=O) which is characteristic of ester absorption. The energy content generated from biodiesel synthesized was estimated as 12,628.5 kJ/mol. Consequently, Kocuria flava MT919305 may provide promising thermostable, methanol-tolerant lipases, which may improve the economic feasibility and biotechnology of enzyme biocatalysis in the synthesis of value-added green chemicals.


Assuntos
Proteínas de Bactérias/metabolismo , Biocombustíveis , Lipase/metabolismo , Metanol/metabolismo , Micrococcaceae/enzimologia , Óleos de Plantas/metabolismo , Biocatálise , Biocombustíveis/análise , Biocombustíveis/microbiologia , Biotecnologia/métodos , Culinária , Gorduras Insaturadas na Dieta/metabolismo , Micrococcaceae/metabolismo
12.
J Adv Res ; 31: 35-47, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34194831

RESUMO

Introduction: Incidents of myocardial infarction and sudden cardiac arrest vary with time of the day, but the mechanism for this effect is not clear. We hypothesized that diurnal changes in the ability of cardiac mitochondria to control calcium homeostasis dictate vulnerability to cardiovascular events. Objectives: Here we investigate mitochondrial calcium dynamics, respiratory function, and reactive oxygen species (ROS) production in mouse heart during different phases of wake versus sleep periods. Methods: We assessed time-of-the-day dependence of calcium retention capacity of isolated heart mitochondria from young male C57BL6 mice. Rhythmicity of mitochondrial-dependent oxygen consumption, ROS production and transmembrane potential in homogenates were explored using the Oroboros O2k Station equipped with a fluorescence detection module. Changes in expression of essential clock and calcium dynamics genes/proteins were also determined at sleep versus wake time points. Results: Our results demonstrate that cardiac mitochondria exhibit higher calcium retention capacity and higher rates of calcium uptake during sleep period. This was associated with higher expression of clock gene Bmal1, lower expression of per2, greater expression of MICU1 gene (mitochondrial calcium uptake 1), and lower expression of the mitochondrial transition pore regulator gene cyclophilin D. Protein levels of mitochondrial calcium uniporter (MCU), MICU2, and sodium/calcium exchanger (NCLX) were also higher at sleep onset relative to wake period. While complex I and II-dependent oxygen utilization and transmembrane potential of cardiac mitochondria were lower during sleep, ROS production was increased presumably due to mitochondrial calcium sequestration. Conclusions: Taken together, our results indicate that retaining mitochondrial calcium in the heart during sleep dissipates membrane potential, slows respiratory activities, and increases ROS levels, which may contribute to increased vulnerability to cardiac stress during sleep-wake transition. This pronounced daily oscillations in mitochondrial functions pertaining to stress vulnerability may at least in part explain diurnal prevalence of cardiac pathologies.


Assuntos
Cálcio/metabolismo , Ritmo Circadiano , Mitocôndrias Cardíacas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sono , Fatores de Transcrição ARNTL/genética , Animais , Canais de Cálcio/genética , Proteínas de Ligação ao Cálcio/genética , Expressão Gênica , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Miocárdio/metabolismo , Fenômenos Fisiológicos Respiratórios
13.
Molecules ; 26(8)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33917024

RESUMO

Beta glucan (ß-glucan) has promising bioactive properties. Consequently, the use of ß-glucan as a food additive is favored with the dual-purpose potential of increasing the fiber content of food products and enhancing their health properties. Our aim was to evaluate the biological activity of ß-glucan (antimicrobial, antitoxic, immunostimulatory, and anticancer) extracted from Saccharomyces cerevisiae using a modified acid-base extraction method. The results demonstrated that a modified acid-base extraction method gives a higher biological efficacy of ß-glucan than in the water extraction method. Using 0.5 mg dry weight of acid-base extracted ß-glucan (AB extracted) not only succeeded in removing 100% of aflatoxins, but also had a promising antimicrobial activity against multidrug-resistant bacteria, fungi, and yeast, with minimum inhibitory concentrations (MIC) of 0.39 and 0.19 mg/mL in the case of resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, respectively. In addition, AB extract exhibited a positive immunomodulatory effect, mediated through the high induction of TNFα, IL-6, IFN-γ, and IL-2. Moreover, AB extract showed a greater anticancer effect against A549, MDA-MB-232, and HepG-2 cells compared to WI-38 cells, at high concentrations. By studying the cell death mechanism using flow-cytometry, AB extract was shown to induce apoptotic cell death at higher concentrations, as in the case of MDA-MB-231 and HePG-2 cells. In conclusion, the use of a modified AB for ß-glucan from Saccharomyces cerevisiae exerted a promising antimicrobial, immunomodulatory efficacy, and anti-cancer potential. Future research should focus on evaluating ß-glucan in various biological systems and elucidating the underlying mechanism of action.


Assuntos
Extração Líquido-Líquido , Saccharomyces cerevisiae/química , beta-Glucanas/isolamento & purificação , beta-Glucanas/farmacologia , Ácidos , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/farmacologia , Imunomodulação/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Extração Líquido-Líquido/métodos , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , beta-Glucanas/química
14.
Chem Phys Lipids ; 231: 104931, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32619464

RESUMO

Synaptosomal membrane peroxidation and alteration in its biophysical properties are associated with Aluminium (Al) toxicity that may lead to cognitive dysfunction and Alzheimer's disease (AD) like pathogenesis. Here we investigated the therapeutic potential of Lepedium sativum (LS) as a natural anti-inflammatory, antioxidant and as acetyl cholinesterase inhibitor in treating Al induced AD-like in rat model. We utilized ATR-IR spectroscopy to follow the restoration in the damaged membrane structure of isolated rat cortical synaptosomes and its biophysical properties, electron paramagnetic resonance (EPR) spin trapping to follow NADPH oxidase activity (NOX), and EPR spin labelling in response to LS treatment after Al intoxication. We measured the concentration of Ca2+ ions in rat cortical tissue by inductively coupled plasma (ICP), the brain atrophy/curing and hydrocephalus by magnetic resonance imaging (MRI) besides light microscope histopathology. Our results revealed significant increase in synaptosomal membrane rgidification, order, lipid packing, reactive oxygen species (ROS) production and Ca2+ ion concentration as a result of Al intoxication. The dramatic increase in Ca2+ ion concentration detected in AD group associated with the increase in synaptic membrane polarity and EPR-detected order S-parameter suggest that release of synaptic vesicles into synaptic cleft might be hindered. LS treatment reversed these changes in synaptic membranes, and rescued an observed deficit in the exploratory behaviour of AD group. Our results also strongly suggest that the synaptosomal membrane phospholipids that underwent free radical attacks mediated by AlCl3, due to greater NOX activity, was prevented in the LS group. The results of ATR-IR and EPR spectroscopic techniques recommend LS as a promising therapeutic agent against synaptic membrane alterations opening a new window for AD drug developers.


Assuntos
Doença de Alzheimer/metabolismo , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Sinaptossomos/metabolismo , Cloreto de Alumínio/administração & dosagem , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/patologia , Animais , Espectroscopia de Ressonância de Spin Eletrônica , Injeções Intraperitoneais , Masculino , Ratos , Ratos Wistar , Espectrofotometria Infravermelho
15.
Vaccines (Basel) ; 8(2)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455708

RESUMO

HEV is the most causative agent of acute viral hepatitis globally. HEV causes acute, chronic, and extrahepatic manifestations. Chronic HEV infection develops in immunocompromised patients such as organ transplant patients, HIV-infected patients, and leukemic patients. The source of chronic HEV infection is not known. Also, the source of extrahepatic manifestations associated with HEV infection is still unclear. Hepatotropic viruses such as HCV and HBV replicate in peripheral blood mononuclear cells (PBMCs) and these cells become a source of chronic reactivation of the infections in allograft organ transplant patients. Herein, we reported that PBMCs and bone marrow-derived macrophages (BMDMs), isolated from healthy donors (n = 3), are susceptible to HEV in vitro. Human monocytes (HMOs), human macrophages (HMACs), and human BMDMs were challenged with HEV-1 and HEV-3 viruses. HEV RNA was measured by qPCR, the marker of the intermediate replicative form (ds-RNA) was assessed by immunofluorescence, and HEV capsid protein was assessed by flow cytometry and ELISA. HEV infection was successfully established in primary HMOs, HMACs, and human BMDMs, but not in the corresponding cells of murine origin. Intermediate replicative form (ds RNA) was detected in HMOs and HMACs challenged with HEV. The HEV load was increased over time, and the HEV capsid protein was detected intracellularly in the HEV-infected cells and accumulated extracellularly over time, confirming that HEV completes the life cycle inside these cells. The HEV particles produced from the infected BMDMs were infectious to naive HMOs in vitro. The HEV viral load was comparable in HEV-1- and HEV-3-infected cells, but HEV-1 induced more inflammatory responses. In conclusion, HMOs, HMACs, and human BMDMs are permissive to HEV infection and these cells could be the source of chronic and recurrent infection, especially in immunocompromised patients. Replication of HEV in human BMDMs could be related to hematological disorders associated with extrahepatic manifestations.

16.
Cells ; 9(3)2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32121073

RESUMO

Exosomes are nano-membrane vesicles that various cell types secrete during physiological and pathophysiological conditions. By shuttling bioactive molecules such as nucleic acids, proteins, and lipids to target cells, exosomes serve as key regulators for multiple cellular processes, including cancer metastasis. Recently, microvesicles have emerged as a challenge in the treatment of prostate cancer (PCa), encountered either when the number of vesicles increases or when the vesicles move into circulation, potentially with an ability to induce drug resistance, angiogenesis, and metastasis. Notably, the exosomal cargo can induce the desmoplastic response of PCa-associated cells in a tumor microenvironment (TME) to promote PCa metastasis. However, the crosstalk between PCa-derived exosomes and the TME remains only partially understood. In this review, we provide new insights into the metabolic and molecular signatures of PCa-associated exosomes in reprogramming the TME, and the subsequent promotion of aggressive phenotypes of PCa cells. Elucidating the molecular mechanisms of TME reprogramming by exosomes draws more practical and universal conclusions for the development of new therapeutic interventions when considering TME in the treatment of PCa patients.


Assuntos
Exossomos/metabolismo , Neoplasias da Próstata/patologia , Animais , Exossomos/imunologia , Humanos , Imunomodulação , Masculino , Modelos Biológicos , Metástase Neoplásica , Microambiente Tumoral
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117535, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31748152

RESUMO

Aluminium (Al) is reported to promote free radical production, decrease the antioxidant enzyme status and disturb the enzyme activity involved in acetylcholine metabolism leading to cognitive dysfunction that are strongly associated with Alzheimer's disease (AD) pathogenesis. This work aimed at investigating the effect of Al-toxicity on synaptosomal membrane biophysical properties and lipid peroxidation during 65 days. We utilized ATR-IR spectroscopy to study the changes in membrane biochemical structure and biophysical properties of isolated rat cortical synaptosomes, and EPR spin trapping and labeling to follow NADPH oxidase activity and changes of membrane order parameter, respectively. The results showed increase in membrane fluidity and disorder in early 21d of AlCl3 treatment, while after 42d the membrane rigidity, packing, and order increased. The late (65d) an increase in the amount of unsaturated fatty acids, the accumulation of lipid peroxide end products, and ROS production were detected in rat cortex synaptosomes mediated by Al toxicity and oxidative stress (OS). A dramatic increase was also detected in Ca2+ level, synaptic membrane polarity, and EPR-detected order S-parameter. These outcomes strongly suggest that the synaptosomal membrane phospholipids underwent free radical attacks mediated by AlCl3 due to greater NOX activity, and the release of synaptic vesicles into synaptic cleft might be hindered. The adopted spectroscopic techniques have shed light on the biomolecular structure and membrane biophysical changes of isolated cortical synaptosomes for the first time, allowing researchers to move closer to a complete understanding of pathological tissues.


Assuntos
Alumínio/toxicidade , Córtex Cerebral/patologia , Estresse Fisiológico , Sinaptossomos/patologia , Animais , Cálcio/metabolismo , Análise por Conglomerados , Espectroscopia de Ressonância de Spin Eletrônica , Hidrocarbonetos/química , Íons , Lipídeos/química , Masculino , Ratos Wistar , Espectrofotometria Infravermelho , Estresse Fisiológico/efeitos dos fármacos , Sinaptossomos/efeitos dos fármacos
18.
J Neurochem ; 153(3): 300-333, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31745996

RESUMO

Despite the human brain being made of nearly 60% fat, the vast majority of studies on the mechanisms of neuronal communication which underpin cognition, memory and learning, primarily focus on proteins and/or (epi)genetic mechanisms. Phospholipids are the main component of all cellular membranes and function as substrates for numerous phospholipid-modifying enzymes, including phospholipases, which release free fatty acids (FFAs) and other lipid metabolites that can alter the intrinsic properties of the membranes, recruit and activate critical proteins, and act as lipid signalling molecules. Here, we will review brain specific phospholipases, their roles in membrane remodelling, neuronal function, learning and memory, as well as their disease implications. In particular, we will highlight key roles of unsaturated FFAs, particularly arachidonic acid, in neurotransmitter release, neuroinflammation and memory. In light of recent findings, we will also discuss the emerging role of phospholipase A1 and the creation of saturated FFAs in the brain.


Assuntos
Memória/fisiologia , Neurônios/enzimologia , Fosfolipases/fisiologia , Animais , Encéfalo/enzimologia , Humanos , Aprendizagem/fisiologia , Fosfolipídeos/fisiologia
19.
J Cell Biochem ; 120(3): 3945-3957, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30260001

RESUMO

Breast cancer is the most common neoplastic disorder diagnosed in women. The main goal of this study was to explore the effect of melatonin against breast cancer metastasis and compared this with the actions of taxol (a well-known chemotherapeutic drug), and the impact of their combination against breast cancer metastasis. Melatonin showed no cytotoxic effect while taxol showed antiproliferative and cytotoxic effects on MCF-7 and MDA-MB-231 cells. Furthermore, melatonin inhibited the generation of reactive oxygen species. Melatonin and taxol clearly decreased cell migration and invasion at low doses, especially those matching the normal physiological concentration at night. Melatonin and taxol markedly reduced DJ-1 and ID-1 and increased KLF17 messenger RNA and protein expression levels. The present results also showed that melatonin and taxol induced GSK3-ß nuclear and Snail cytosolic localization. These changes were accompanied by a concurrent rise in E-cadherin expression. The above data show that normal levels of melatonin may help in preventing breast cancer metastasis through inhibiting DJ-1/KLF17/ID-1 signaling pathway. The combination of melatonin and taxol is a potent candidate against breast cancer metastasis, better than using melatonin or taxol as a single drug.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proteína 1 Inibidora de Diferenciação/genética , Melatonina/farmacologia , Proteína Desglicase DJ-1/genética , Fatores de Transcrição/genética , Antígenos CD/genética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Caderinas/genética , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Células MCF-7 , Invasividade Neoplásica/genética , Metástase Neoplásica , Paclitaxel/farmacologia , Transdução de Sinais/efeitos dos fármacos
20.
Artigo em Inglês | MEDLINE | ID: mdl-29701902

RESUMO

Paclitaxel (taxol) is an important agent against many tumours, including breast cancer. Ample data documents that paclitaxel inhibits breast cancer metastasis while others prove that paclitaxel enhances breast cancer metastasis. The mechanisms by which paclitaxel exerts its action are not well established. This study focuses on the effect of paclitaxel, particularly the low doses on breast cancer metastasis and the mechanisms that regulate it. Current results show that, paclitaxel exerts significant cytotoxicity even at low doses in both MCF-7 and MDA-MB-231 cells. Interestingly, paclitaxel significantly inhibits cell invasion and migration, decreases Snail and increases E-cadherin mRNA expression levels at the indicated low doses. Furthermore, paclitaxel-inhibiting breast cancer metastasis is associated with down-regulation of DJ-1 and ID-1 mRNA expression level with a concurrent increase in KLF17 expression. Under the same experimental conditions, paclitaxel induces KLF17 and concurrently represses ID-1 protein levels. Our results show for the first time that paclitaxel inhibits breast cancer metastasis through regulating DJ-1/KLF17/ID-1 signalling pathway; repressed DJ-1 and ID-1 and enhanced KLF17 expression.

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