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1.
J Transl Med ; 22(1): 82, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245790

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a liver disorder characterized by the ac-cumulation of fat in hepatocytes without alcohol consumption. Mitochondrial dysfunction and endoplasmic reticulum (ER) stress play significant roles in NAFLD pathogenesis. The unfolded protein response in mitochondria (UPRmt) is an adaptive mechanism that aims to restore mitochondrial protein homeostasis and mitigate cellular stress. This study aimed to investigate the effects of ( +)-Lipoic acid (ALA) on UPRmt, inflammation, and oxidative stress in an in vitro model of NAFLD using HepG2 cells treated with palmitic acid and oleic acid to induce steatosis. RESULTS: Treatment with palmitic and oleic acids increased UPRmt-related proteins HSP90 and HSP60 (heat shock protein), and decreased CLPP (caseinolytic protease P), indicating ER stress activation. ALA treatment at 1 µM and 5 µM restored UPRmt-related protein levels. PA:OA (palmitic acid:oleic acid)-induced ER stress markers IRE1α (Inositol requiring enzyme-1), CHOP (C/EBP Homologous Protein), BIP (Binding Immunoglobulin Protein), and BAX (Bcl-2-associated X protein) were significantly reduced by ALA treatment. ALA also enhanced ER-mediated protein glycosylation and reduced oxidative stress, as evidenced by decreased GPX1 (Glutathione peroxidase 1), GSTP1 (glutathione S-transferase pi 1), and GSR (glutathione-disulfide reductase) expression and increased GSH (Glutathione) levels, and improved cellular senescence as shown by the markers ß-galactosidase, γH2Ax and Klotho-beta. CONCLUSIONS: In conclusion, ALA ameliorated ER stress, oxidative stress, and inflammation in HepG2 cells treated with palmitic and oleic acids, potentially offering therapeutic benefits for NAFLD providing a possible biochemical mechanism underlying ALA beneficial effects.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Ácido Tióctico , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico , Ácido Tióctico/metabolismo , Endorribonucleases/metabolismo , Ácido Oleico/farmacologia , Ácido Oleico/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Resposta a Proteínas não Dobradas , Estresse Oxidativo , Estresse do Retículo Endoplasmático , Hepatócitos/patologia , Senescência Celular , Inflamação/patologia , Ácidos Palmíticos/metabolismo , Ácidos Palmíticos/farmacologia , Fígado/patologia , Ácido Palmítico/farmacologia , Ácido Palmítico/metabolismo
3.
Metabolites ; 13(7)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37512586

RESUMO

Tumor onset and its progression are strictly linked to its metabolic rewiring on the basis of the Warburg effect. In this context, fumarate emerged as a putative oncometabolite mediating cancer progression. Fumarate accumulation is usually driven by fumarate hydratase (FH) loss of function, the enzyme responsible for the reversible conversion of fumarate into malate. Fumarate accumulation acts as a double edge sword: on one hand it takes part in the metabolic rewiring of cancer cells, while on the other it also plays a crucial role in chromatin architecture reorganization. The latter is achieved by competing with a-ketoglutarate-dependent enzymes, eventually altering the cellular methylome profile, which in turn leads to its transcriptome modeling. Furthermore, in recent years, it has emerged that FH has an ability to recruit DNA double strand breaks. The accumulation of fumarate into damaged sites might also determine the DNA repair pathway in charge for the seizure of the lesion, eventually affecting the mutational state of the cells. In this work, we aimed to review the current knowledge on the role of fumarate as an oncometabolite orchestrating the cellular epigenetic landscape and DNA repair machinery.

4.
Int J Mol Sci ; 24(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902172

RESUMO

The coronavirus disease 19 (COVID-19) post pandemic evolution is correlated to the development of new variants. Viral genomic and immune response monitoring are fundamental to the surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Since 1 January to 31 July 2022, we monitored the SARS-CoV-2 variants trend in Ragusa area sequencing n.600 samples by next generation sequencing (NGS) technology: n.300 were healthcare workers (HCWs) of ASP Ragusa. The evaluation of anti-Nucleocapside (N), receptor-binding domain (RBD), the two subunit of S protein (S1 and S2) IgG levels in 300 exposed vs. 300 unexposed HCWs to SARS-CoV-2 was performed. Differences in immune response and clinical symptoms related to the different variants were investigated. The SARS-CoV-2 variants trend in Ragusa area and in Sicily region were comparable. BA.1 and BA.2 were the most representative variants, whereas the diffusion of BA.3 and BA.4 affected some places of the region. Although no correlation was found between variants and clinical manifestations, anti-N and anti-S2 levels were positively correlated with an increase in the symptoms number. SARS-CoV-2 infection induced a statistically significant enhancement in antibody titers compared to that produced by SARS-CoV-2 vaccine administration. In post-pandemic period, the evaluation of anti-N IgG could be used as an early marker to identify asymptomatic subjects.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Anticorpos Antivirais/sangue , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Imunoglobulina G/sangue , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Sicília/epidemiologia
5.
Antioxidants (Basel) ; 11(8)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36009316

RESUMO

Hemoglobin and iron overload is considered the major contributor to intracerebral hemorrhage (ICH)-induced brain injury. Accumulation of iron in the brain leads to microglia activation, inflammation and cell loss. Current available treatments for iron overload-mediated disorders are characterized by severe adverse effects, making such conditions an unmet clinical need. We assessed the potential of α-lipoic acid (ALA) as an iron chelator, antioxidant and anti-inflammatory agent in both in vitro and in vivo models of iron overload. ALA was found to revert iron-overload-induced toxicity in HMC3 microglia cell line, preventing cell apoptosis, reactive oxygen species generation and reducing glutathione depletion. Furthermore, ALA regulated gene expression of iron-related markers and inflammatory cytokines, such as IL-6, IL-1ß and TNF. Iron toxicity also affects mitochondria fitness and biogenesis, impairments which were prevented by ALA pre-treatment in vitro. Immunocytochemistry assay showed that, although iron treatment caused inflammatory activation of microglia, ALA treatment resulted in increased ARG1 expression, suggesting it promoted an anti-inflammatory phenotype. We also assessed the effects of ALA in an in vivo zebrafish model of iron overload, showing that ALA treatment was able to reduce iron accumulation in the brain and reduced iron-mediated oxidative stress and inflammation. Our data support ALA as a novel approach for iron-overload-induced brain damage.

6.
Biomolecules ; 11(1)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33477816

RESUMO

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by hematopoietic stem-cell-derived clonal proliferation, leading to bone marrow (BM) fibrosis. Hematopoiesis alterations are closely associated with modifications of the BM microenvironment, characterized by defective interactions between vascular and endosteal niches. As such, neoangiogenesis, megakaryocytes hyperplasia and extensive bone marrow fibrosis, followed by osteosclerosis and bone damage, are the most relevant consequences of PMF. Moreover, bone tissue deposition, together with progressive fibrosis, represents crucial mechanisms of disabilities in patients. Although the underlying mechanisms of bone damage observed in PMF are still unclear, the involvement of cytokines, growth factors and bone marrow microenvironment resident cells have been linked to disease progression. Herein, we focused on the role of megakaryocytes and their alterations, associated with cytokines and chemokines release, in modulating functions of most of the bone marrow cell populations and in creating a complex network where impaired signaling strongly contributes to progression and disabilities.


Assuntos
Progressão da Doença , Osteosclerose/parasitologia , Mielofibrose Primária/patologia , Animais , Medula Óssea , Humanos , Monócitos/patologia , Transdução de Sinais
7.
Neural Regen Res ; 13(4): 692-698, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29722322

RESUMO

Peripheral neuropathies are chronic painful syndromes characterized by allodynia, hyperalgesia and altered nerve functionality. Nerve tissue degeneration represents the microanatomical correlate of peripheral neuropathies. Aimed to improve the therapeutic possibilities, this study investigated the hypersensitivity and the neuromorphological alterations related to the loose ligation of the sciatic nerve in rats. Effects elicited by treatment with acetyl-L-carnitine (ALCAR) in comparison to gabapentin were assessed. Axonal injury, reduction of myelin deposition and accumulation of inflammatory cells were detected in damaged nerve. A decrease of phosphorylated 200-kDa neurofilament (NFP) immunoreactivity and a redistribution in small clusters of myelin basic like-protein (MBP) were observed in ipsilateral nerves. Treatment with ALCAR (100 mg/kg intraperitoneally - i.p.) and gabapentin (70 mg/kg i.p.) administered bis in die for 14 days induced a significant pain relieving effect. ALCAR, but not gabapentin, significantly countered neuromorphological changes and increased axonal NFP immunoreactivity. These findings indicate that both ALCAR and gabapentin significantly decreased the hypersensitivity related to neuropathic lesions. The observation of the positive ALCAR effect on axonal and myelin sheath alterations in damaged nerve supports its use as neurorestorative agent against neuropathies through mechanism(s) consistent to those focused in this study.

8.
Mol Neurobiol ; 55(4): 3344-3350, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28497200

RESUMO

Neuroblastoma (NB) is an extracranial solid cancer and the most common cancer in infancy. Despite the standard treatment for NB is based on the combination of chemotherapeutic drugs such as doxorubicin, vincristine, cyclophosphamide, and cisplatin, chemoresistance occurs over the time. The aim of the present research was to evaluate the effect of bortezomib (BTZ) (50 nM) on NB cell viability and how lipoic acid (ALA) (100 µM) modifies pharmacological response to this chemotherapeutic agent. Cell viability was assessed by ATP luminescence assay whereas expression of oxidative stress marker (i.e., heme oxygenase-1) and endoplasmic reticulum stress proteins was performed by real-time PCR, western blot, and immunofluorescence. Our data showed that BTZ treatment significantly reduced cell viability when compared to untreated cultures (about 40%). Interestingly, ALA significantly reduced the efficacy of BTZ (about 30%). Furthermore, BTZ significantly induced heme oxygenase-1 as a result of increased oxidative stress and such overexpression was prevented by concomitant treatment with ALA. Similarly, ALA significantly reduced BTZ-mediated endoplasmic reticulum stress as measured by reduction in BiP1 and IRE1α, ERO1α, and PDI expression. In conclusion, our data suggest that BTZ efficacy is dependent on cellular redox status and such mechanisms may be responsible of chemoresistance to this chemotherapeutic agent.


Assuntos
Bortezomib/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neuroblastoma/patologia , Ácido Tióctico/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Proteínas de Neoplasias/metabolismo , Transporte Proteico/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
9.
Inflamm Res ; 66(11): 947-959, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28676917

RESUMO

BACKGROUND: The molecular nature of lipoic acid (LA) clarifies its capability of taking part to a variety of biochemical reactions where redox state is meaningful. The pivotal action of LA is the antioxidant activity due to its ability to scavenge and inactivate free radicals. Furthermore, LA has been shown to chelate toxic metals both directly and indirectly by its capability to enhance intracellular glutathione (GSH) levels. This last property is due to its ability to interact with GSH and recycle endogenous GSH. LA exhibits significant antioxidant activity protecting against oxidative damage in several diseases, including neurodegenerative disorders. Interestingly, LA is unique among natural antioxidants for its capability to satisfy a lot of requirements, making it a potentially highly effective therapeutic agent for many conditions related with oxidative damage. In particular, there are evidences showing that LA has therapeutic activity in lowering glucose levels in diabetic conditions. Similarly, LA supplementation has multiple beneficial effects on the regression of the mitochondrial function and on oxidative stress associated with several diseases and aging. AIM: The aim of the present review is to describe the molecular mechanisms underlying the beneficial effects of LA under various experimental conditions and disease and how to exploit such effect for clinical purposes. CONCLUSION: LA has pleiotropic effects in different pathways related with several diseases, its use as a potential therapeutic agent is very promising.


Assuntos
Anti-Inflamatórios , Antioxidantes , Ácido Tióctico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos , Transdução de Sinais , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico
10.
Nutrients ; 8(10)2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27706074

RESUMO

Multiple myeloma (MM) is a clonal B-cell malignancy characterized by an accumulation of clonal plasma cells (PC) in the bone marrow (BM) leading to bone destruction and BM failure. Despite recent advances in pharmacological therapy, MM remains a largely incurable pathology. Therefore, novel effective and less toxic agents are urgently necessary. In the last few years, pomegranate has been studied for its potential therapeutic properties including treatment and prevention of cancer. Pomegranate juice (PGJ) contains a number of potential active compounds including organic acids, vitamins, sugars, and phenolic components that are all responsible of the pro-apoptotic effects observed in tumor cell line. The aim of present investigation is to assess the antiproliferative and antiangiogenic potential of the PGJ in human multiple myeloma cell lines. Our data demonstrate the anti-proliferative potential of PGJ in MM cells; its ability to induce G0/G1 cell cycle block and its anti-angiogenic effects. Interestingly, sequential combination of bortezomib/PGJ improved the cytotoxic effect of the proteosome inhibitor. We investigated the effect of PGJ on angiogenesis and cell migration/invasion. Interestingly, we observed an inhibitory effect on the tube formation, microvessel outgrowth aorting ring and decreased cell migration and invasion as showed by wound-healing and transwell assays, respectively. Analysis of angiogenic genes expression in endothelial cells confirmed the anti-angiogenic properties of pomegranate. Therefore, PGJ administration could represent a good tool in order to identify novel therapeutic strategies for MM treatment, exploiting its anti-proliferative and anti-angiogenic effects. Finally, the present research supports the evidence that PGJ could play a key role of a future therapeutic approach for treatment of MM in order to optimize the pharmacological effect of bortezomib, especially as adjuvant after treatment.


Assuntos
Inibidores da Angiogênese/farmacologia , Bebidas , Proliferação de Células/efeitos dos fármacos , Frutas/química , Lythraceae , Mieloma Múltiplo/tratamento farmacológico , Antineoplásicos Fitogênicos , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Flavonoides , Humanos , Mieloma Múltiplo/irrigação sanguínea , Mieloma Múltiplo/patologia , Invasividade Neoplásica/prevenção & controle , Fitoterapia , Taninos , Fator A de Crescimento do Endotélio Vascular/farmacologia
11.
PLoS One ; 11(9): e0159874, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27631977

RESUMO

It is suspected that microbial infections take part in the pathogenesis of diabetes mellitus type 1 (T1DM). Glucose-induced insulin secretion is accompanied by the release of free arachidonic acid (AA) mainly by cytosolic- and calcium independent phospholipases A2 (cPLA2 and iPLA2). Insulinoma cell line (INS-1E) was infected with E. coli isolated from the blood culture of a patient with sepsis. Invasion assay, Scanning Electron Microscopy and Transmission Electron Microscopy demonstrated the capacity of E. coli to enter cells, which was reduced by PLA2 inhibitors. Glucose-induced insulin secretion was significantly increased after acute infection (8h) but significantly decreased after chronic infection (72h). PLA2 activities, cPLA2, iPLA2, phospho-cPLA2, and COX-2 expressions were increased after acute and, even more, after chronic E. coli infection. The silencing of the two isoforms of PLA2s, with specific cPLA2- or iPLA2-siRNAs, reduced insulin secretion after acute infection and determined a rise in insulin release after chronic infection. Prostaglandins E2 (PGE2) production was significantly elevated in INS-1E after long-term E. coli infection and the restored insulin secretion in presence of L798106, a specific EP3 antagonist, and NS-398, a COX-2 inhibitor, and the reduction of insulin secretion in presence of sulprostone, a specific EP3 agonist, revealed their involvement in the effects triggered by bacterial infection. The results obtained demonstrated that cPLA2 and iPLA2 play a key role in insulin secretion process after E. coli infection. The high concentration of AA released is transformed into PGE2, which could be responsible for the reduced insulin secretion.


Assuntos
Cálcio/metabolismo , Citosol/metabolismo , Dinoprostona/metabolismo , Escherichia coli/metabolismo , Insulina/metabolismo , Fosfolipases A2/metabolismo , Linhagem Celular , Ativação Enzimática , Humanos , Secreção de Insulina
12.
PLoS One ; 11(7): e0158392, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27391078

RESUMO

It is well known that mesenchymal stem cells (MSC) have a role in promotion of tumor growth, survival and drug-resistance in chronic myeloid leukemia (CML). Recent reports indicated that a subpopulation of myeloid cells, defined as granulocyte-like myeloid-derived suppressor cells (G-MDSC) is increased in these patients. So far, the role of MSC in MDSC expansion and activation into the BM microenvironment remains unexplored. To address this question, here we use a specific experimental model in vitro, co-culturing MSC with peripheral blood mononucleated cells (PBMC) from normal individuals, in order to generate MSC-educated G-MDSC. Although MSC of healthy donors (HD) and CML patients were able to generate the same amount of MDSC, only CML-MSC-educated G-MDSC exhibited suppressive ability on autologous T lymphocytes. In addition, compared with HD-MSC, CML-MSC over-expressed some immunomodulatory factors including TGFß, IL6 and IL10, that could be involved in MDSC activation. CML-MSC-educated G-MDSC expressed higher levels of ARG1, TNFα, IL1ß, COX2 and IL6 than G-MDSC isolated from co-culture with HD-MSC. Our data provide evidence that CML-MSC may play a critical role in tumor microenvironment by orchestrating G-MDSC activation and regulating T lymphocytes-mediated leukemia surveillance, thus contributing to CML immune escape.


Assuntos
Granulócitos/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Células-Tronco Mesenquimais/metabolismo , Modelos Biológicos , Microambiente Tumoral , Adulto , Idoso , Feminino , Granulócitos/patologia , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Células-Tronco Mesenquimais/patologia , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo
13.
Front Physiol ; 7: 153, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27199768

RESUMO

The increase of heavy metals in the environment involves a high exposure of aquatic organisms to these pollutants. The present study is planned to investigate the effects of zinc chloride (ZnCl2) on the bone embryonic development of Danio rerio and confirm the use of zebrafish as a model organism to study the teratogenic potential of this pollutant. Zebrafish embryos were exposed to different ZnCl2 concentrations and analyzed by ICP-MS. The skeletal anomalies were evaluated to confocal microscope after staining with calcein solution and RhodZin(TM)-3,AM. The data show a delay in hatching compared with the controls, malformations in the process of calcification and significant defects in growth. In conclusion, the current work demonstrates for the first time the Zn toxic effects on calcification process and confirm zebrafish (Danio rerio) as suitable alternative vertebrate model to study the causes and the mechanisms of the skeletal malformations.

14.
Front Physiol ; 7: 130, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27148069

RESUMO

The effect of the nanoparticles on the marine organisms, depends on their size, chemical composition, surface structure, solubility and shape. In order to take advantage from their activity, preserving the surrounding environment from a possible pollution, we are trying to trap the nanoparticles into new nanomaterials. The nanomaterials tested were synthesized proposing a ground-breaking approach by an upside-down vision of the Au/TiO2 nano-system to avoid the release of nanoparticles. The system was synthesized by wrapping Au nanoparticles with a thin layer of TiO2. The non-toxicity of the nano-system was established by testing the effect of the material on zebrafish larvae. Danio rerio o zebrafish was considered an excellent model for the environmental biomonitoring of aquatic environments and the Zebrafish Embryo Toxicity Test (ZFET) is considered an alternative method of animal test. For this reason zebrafish larvae were exposed to different concentrations of nanoparticles of TiO2 and Au and new nanomaterials. As biomarkers of exposure, we evaluated the expression of metallothioneins by immunohistochemistry analysis and western blotting analysis also. The results obtained by toxicity test showed that neither mortality as well as sublethal effects were induced by the different nanomaterials and nanoparticles tested. Only zebrafish larvae exposed to free Au nanoparticles showed a different response to anti-MT antibody. In fact, the immunolocalization analysis highlighted an increase of the metallothioneins synthesis.

15.
Oncotarget ; 7(52): 85764-85775, 2016 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-26967390

RESUMO

Granulocytic-Myeloid-derived suppressor cells (G-MDSC) are increased in Multiple Myeloma (MM) patients but the mechanisms of G-MDSC generation are still unknown. There are many evidences of the role of mesenchymal stem cells (MSC) in promoting MM cell growth, survival and drug-resistance. We here used a specific experimental model in vitro to evaluate the ability of MSC to induce G-MDSC. We found that although MSC derived from healthy donors (HD), MGUS and MM were able to generate the same amount of MDSC, only MM-MSC-educated G-MDSC exhibited suppressive ability. In addition, in comparison with MSC derived from HD, MM-MSC produce higher amount of immune-modulatory factors that could be involved in MDSC induction. Compared to G-MDSC obtained from co-culture models with MSC from healthy subjects, both MGUS and MM-MSC-educated G-MDSC showed increase of immune-modulatory factors. However, only MM-MSC educated G-MDSC 1) up-regulated immune-suppressive factors as ARG1 and TNFα, 2) expressed higher levels of PROK2, important in angiogenesis and inflammatory process, and 3) showed ability to digest bone matrix.Our data demonstrate that MM-MSC are functionally different from healthy subjects and MGUS-MSC, supporting an evolving concept regarding the contribution of MM-MSC to tumor development and progression.


Assuntos
Granulócitos/fisiologia , Células-Tronco Mesenquimais/fisiologia , Mieloma Múltiplo/imunologia , Células Supressoras Mieloides/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/etiologia , Microambiente Tumoral
16.
Front Pharmacol ; 7: 519, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28111549

RESUMO

Primary solid tumors originate close to pre-existing tissue vasculature, initially growing along such tissue blood vessels, and this phenomenon is important for the metastatic potential which frequently occurs in highly vascularized tissues. Unfortunately, preclinic and clinic anti-angiogenic approaches have not been very successful, and multiple factors have been found to contribute to toxicity and tumor resistance. Moreover, tumors can highlight intrinsic or acquired resistances, or show adaptation to the VEGF-targeted therapies. Furthermore, different mechanisms of vascularization, activation of alternative signaling pathways, and increased tumor aggressiveness make this context even more complex. On the other hand, it has to be considered that the transitional restoration of normal, not fenestrated, microvessels allows the drug to reach the tumor and act with the maximum efficiency. However, these effects are time-limited and different, depending on the various types of cancer, and clearly define a specific "normalization window." So, new horizons in the therapeutic approaches consist on the treatment of the tumor with pro- (instead of anti-) angiogenic therapies, which could strengthen a network of well-structured blood vessels that facilitate the transport of the drug.

17.
J Neurosci Res ; 94(1): 90-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26469526

RESUMO

Steroid hormones and neurotrophic factors regulate astroglial cell survival, proliferation, and differentiation in culture. The present study examines the interaction between glucocorticoids and growth factors (GFs) on cytoskeletal proteins and extracellular signal-regulated kinase 2 (ERK2) expression in stressed astroglial cultures at 25 days in vitro, according to the following experimental condition. Pretreatment with basic fibroblast growth factor alone or in combination with dexamethasone 10(-9) M for 48 hr induced an enhancement of glial fibrillary acidic protein, vimetin, and ERK2 expression. Treatment with "progression" GFs alone and in the last 12 hr significantly increased the above-mentioned markers' expression. The present study shows that glucocorticoids may cooperate with GFs or may abrogate their effects, depending on the experimental culture conditions used as well as the exposure time and the types of GFs added. Our findings provide evidence of interactive dialogue between GFs and neurosteroids in cultured astrocytes. This may have implications in the therapeutic approach to neurologic disorders associated with astrogliosis.


Assuntos
Astrócitos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Glucocorticoides/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Análise de Variância , Animais , Astrócitos/metabolismo , Encéfalo/citologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Ictiose Lamelar , Ratos , Ratos Wistar , Fatores de Tempo
18.
Am J Physiol Regul Integr Comp Physiol ; 309(5): R585-93, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26136535

RESUMO

The localization of dopamine stores and the expression and localization of dopamine (DAT) and vesicular monoamine transporters (VMAT) type-1 and -2 and of dopamine D1-like and D2-like receptor subtypes were investigated in rat submandibular, sublingual, and parotid salivary glands by HPLC with electrochemical detection, as well as immunochemical and immunohistochemical techniques. Male Wistar rats of 2 mo of age were used. The highest dopamine levels were measured in the parotid gland, followed by the submandibular and sublingual glands. Western blot analysis revealed DAT, VMAT-1, VMAT-2, and dopamine receptors immunoreactivity in membrane preparations obtained from the three glands investigated. Immunostaining for dopamine and transporters was developed within striated ducts. Salivary glands processed for dopamine receptors immunohistochemistry developed an immunoreaction primarily in striated and excretory ducts. In the submandibular gland, acinar cells displayed strong immunoreactivity for the D2 receptor, while cells of the convoluted granular tubules were negative for both D1-like and D2-like receptors. Parotid glands acinar cells displayed the highest immunoreactivity for both D1 and D2 receptors compared with other salivary glands. The above localization of dopamine and dopaminergic markers investigated did not correspond closely with neuron-specific enolase (NSE) localization. This indicates that at least in part, catecholamine stores and dopaminergic markers are independent from glandular innervation. These findings suggest that rat major salivary glands express a dopaminergic system probably involved in salivary secretion. The stronger immunoreactivity for dopamine transporters and receptors in striated duct cells suggests that the dopaminergic system could regulate not only quality, but also volume and ionic concentration of saliva.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina/análise , Dopamina/análise , Receptores Dopaminérgicos/análise , Glândulas Salivares/química , Proteínas Vesiculares de Transporte de Monoamina/análise , Animais , Western Blotting , Cromatografia Líquida de Alta Pressão , Neurônios Dopaminérgicos/química , Imuno-Histoquímica , Masculino , Glândula Parótida/química , Fosfopiruvato Hidratase/análise , Ratos Wistar , Receptores de Dopamina D1/análise , Receptores de Dopamina D2/análise , Glândulas Salivares/inervação , Glândula Sublingual/química , Glândula Submandibular/química
19.
J Neurosci Res ; 93(9): 1378-87, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26053243

RESUMO

The present study seeks to elucidate the interactions between the "competence" growth factor basic fibroblast growth factor (bFGF) and/or estrogen 17ß-estradiol and the "progression" growth factors epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), and insulin (INS) on DNA labeling and also cyclin D1, extracellular signal-related kinase 1/2 (ERK1/2), glial fibrillary acidic protein (GFAP), and vimentin expression in astroglial cultures under different experimental conditions. Pretreatment for 24 hr with bFGF and subsequent exposure for 36 hr to estradiol (E2 ) and EGF, IGF-I, or INS stimulated DNA labeling in the last 12 hr, especially when the cultures were treated with progression growth factors. bFGF pretreatment and subsequent treatment with E2 for 36 hr stimulated DNA labeling. The 36-hr E2 treatment alone did not significantly decrease DNA labeling, but contemporary addition of E2 with two or three growth factors stimulated DNA labeling remarkably. When E2 was coadded with growth factors, a significantly increased DNA labeling was observed, demonstrating an astroglial synergistic mitogenic effect evoked by contemporary treatment with growth factors in the presence of estrogens. Cyclin D1 expression was markedly increased when astrocyte cultures were pretreated for 36 hr with E2 and subsequently treated with two or three competence and progression growth factors. A highly significant increase of ERK1/2 expression was observed after all the treatments (EGF, bFGF, INS, IGF-I alone or in combination with two or three growth factors). GFAP and vimentin expression was markedly increased when the cultures were treated with two or three growth factors. In conclusion, our data demonstrate estradiol-growth factor cross-talk during astroglial cell proliferation and differentiation in culture.


Assuntos
Astrócitos/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Vimentina/metabolismo , Análise de Variância , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Células Cultivadas , Interações Medicamentosas , Regulação da Expressão Gênica/efeitos dos fármacos , Insulina/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Ratos , Ratos Wistar , Timidina/metabolismo , Fatores de Tempo , Trítio/metabolismo
20.
Curr Alzheimer Res ; 10(10): 1070-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24156263

RESUMO

Cholinergic precursors have represented the first approach to counter cognitive impairment occurring in adultonset dementia disorders. These compounds were early leaved because their clinical efficacy was not clearly demonstrated. This is probably not true for some choline-containing phospholipids including choline alphoscerate. Choline alphoscerate increases the release of acetylcholine in rat hippocampus, facilitates learning and memory in experimental animals, improves brain transduction mechanisms and decreases age-dependent structural changes occurring in rat brain areas involved in learning and memory. The compound exerts neuroprotective effects in models of altered cholinergic neurotransmission and of brain vascular injury. In clinical studies choline alphoscerate improved memory and attention impairment, as well as affective and somatic symptoms in dementia disorders. An ongoing trial indicates that association between the acetylcholinesterase inhibitor donepezil and choline alphoscerate is accompanied by an improvement in several cognitive tests superior to that induced by donepezil alone. It is suggested that this association may represent a therapeutic option to prolong beneficial effects of cholinergic therapies in Alzheimer's disease patients with concomitant ischemic cerebrovascular disorders. In summary, choline alphoscerate has significant effects on cognitive function with a good safety profile and tolerability. Although limited both in terms of size of the samples investigated and of the length of treatment, preclinical and clinical results presented suggest that cognitive enhancing capabilities of choline alphoscerate merit of being further investigated in appropriate trials.


Assuntos
Encéfalo/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Cognição/efeitos dos fármacos , Glicerilfosforilcolina/farmacologia , Glicerilfosforilcolina/uso terapêutico , Animais , Encéfalo/metabolismo , Humanos , Fosfolipídeos/metabolismo
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