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Current evidence supports the beneficial role of phytoestrogens in metabolic diseases, but their influences on spontaneous motor and anxiety behaviors plus neuroprotective effects have still not been completely elucidated. With the present study, neuro-behavioral activities were correlated to daidzein (DZ)-dependent expression changes of a high affinity catalytic receptor for several neurotrophins, and namely tropomyosin-related kinase B receptor (TrkB) in the cerebellar cortex of high-fat diet (HFD) hamsters (Mesocricetus auratus). Indeed, these changes appear to be tightly linked to altered plasma lipid profiles as shown by reduced low-density lipoproteins plus total cholesterol levels in DZ-treated obesity hamsters accounting for increased spontaneous locomotor together with diminished anxiety activities in novel cage (NCT) and light/dark box (LDT) tests. For this latter case, the anxiolytic-like hamsters spent more time in the light compartment, which was retained the aversive area of the LDT box. As for the evaluation of the neurotrophin receptor site, significantly elevated TrkB levels were also detected, for the first time, in the cerebellum of obese hamsters treated with DZ. In this condition, such a treatment widely led to an overall improvement of HFD-induced neurodegeneration damages, above all in the Purkinje and granular layers of the cerebellum. In this context, the notably active TrkB signaling events occurring in a DZ-dependent manner may turn out to be a key neuroprotective element capable of restoring normal emotional and spontaneously linked locomotor behaviors regulated by cerebellar cortical areas especially in obesity-related conditions.
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Isoflavonas , Obesidade , Cricetinae , Animais , Ansiedade/etiologia , CerebeloRESUMO
BACKGROUND: Androgens, through their own receptor, play a protective role on breast tumor development and progression and counterbalance estrogen-dependent growth stimuli which are intimately linked to breast carcinogenesis. METHODS: Cell counting by trypan blu exclusion was used to study androgen effect on estrogen-dependent breast tumor growth. Quantitative Real Time RT-PCR, western blotting, transient transfection, protein immunoprecipitation and chromatin immunoprecipitation assays were carried out to investigate how androgen treatment and/or androgen receptor overexpression influences the functional interaction between the steroid receptor coactivator AIB1 and the estrogen- or androgen receptor which, in turn affects the estrogen-induced cyclin D1 gene expression in MCF-7 breast cancer cells. Data were analyzed by ANOVA. RESULTS: Here we demonstrated, in estrogen receptor α (ERα)-positive breast cancer cells, an androgen-dependent mechanism through which ligand-activated androgen receptor (AR) decreases estradiol-induced cyclin D1 protein, mRNA and gene promoter activity. These effects involve the competition between AR and ERα for the interaction with the steroid receptor coactivator AIB1, a limiting factor in the functional coupling of the ERα with the cyclin D1 promoter. Indeed, AIB1 overexpression is able to reverse the down-regulatory effects exerted by AR on ERα-mediated induction of cyclin D1 promoter activity. Co-immunoprecipitation studies indicated that the preferential interaction of AIB1 with ERα or AR depends on the intracellular expression levels of the two steroid receptors. In addition, ChIP analysis evidenced that androgen administration decreased E2-induced recruitment of AIB1 on the AP-1 site containing region of the cyclin D1 gene promoter. CONCLUSIONS: Taken together all these data support the hypothesis that AIB1 sequestration by AR may be an effective mechanism to explain the reduction of estrogen-induced cyclin D1 gene activity. In estrogen-dependent breast cancer cell proliferation, these findings reinforce the possibility that targeting AR signalling may potentiate the effectiveness of anti-estrogen adjuvant therapies.
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Neoplasias da Mama/metabolismo , Ciclina D1/genética , Receptor alfa de Estrogênio/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Receptores Androgênicos/metabolismo , Ciclina D1/metabolismo , Estradiol/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Coativador 3 de Receptor Nuclear/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica , RNA Mensageiro/genética , Transdução de Sinais , Fator de Transcrição AP-1/genéticaRESUMO
Keywords: carbazole; tetrahydrocarbazole; antiviral agents.
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Antivirais/farmacologia , Carbazóis/farmacologia , Viroses/epidemiologia , Animais , Antivirais/química , Antivirais/uso terapêutico , Carbazóis/química , Carbazóis/uso terapêutico , Humanos , Estrutura Molecular , Mutação , Pandemias/veterinária , Viroses/tratamento farmacológico , Vírus/efeitos dos fármacos , Vírus/genéticaRESUMO
I prophylaxis is the most effective strategy to eradicate I deficiency disorders, but it has been shown to affect the thyroid disease pattern. In this study, we assessed the frequency of thyroid disorders in an adult population living in two areas of southern Italy after implementing I prophylaxis. To this aim, a cross-sectional, population-based study including 489 subjects from an I-deficient rural and an I-sufficient urban area of southern Italy was conducted. Thyroid ultrasound was performed on all participants, and urine and blood samples were collected from each subject. The levels of thyroid-stimulating hormone (TSH), thyroglobulin (TgAb) and thyroperoxidase antibodies (TPOAb), urinary I excretion (UIE), and thyroid volume and echogenicity were evaluated. We found that the median UIE was higher in the urban than in the rural area (P=0·004), whereas the prevalence of subjects affected by goitre was higher in the rural compared with the urban area (P=0·003). Positive TgAb rather than TPOAb were more frequent in subjects from the urban area compared with the rural area (P=0·009). The hypoechoic pattern at thyroid ultrasound (HT-US) was similar between the two areas, but TgAb were significantly higher (P=0·01) in HT-US subjects from the urban area. The frequency of elevated TSH did not differ between the two screened populations, and no changes were found for TgAb positivity in subjects with high TSH in the urban compared with the rural area. Our findings support that the small risks of I supplementation are far outweighed by the substantial benefits of correcting I deficiency, although continued monitoring of populations is necessary.
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Iodo/administração & dosagem , Iodo/deficiência , Doenças da Glândula Tireoide/epidemiologia , Doenças da Glândula Tireoide/prevenção & controle , Adulto , Estudos Transversais , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-IdadeRESUMO
Abstract Recent reports support the possible role of PI3K in sperm capacitation and acrosome reaction, although studies regarding PI3K identity in human sperm, under certain disease states such as varicocele, are still lacking. The authors, therefore, examined the expression profile and ultrastructural localization of PI3K in human semen samples, comparing healthy donors and patients with varicocele. The results obtained performing western blotting assay showed decreased PI3K expression in varicocele with respect to the "healthy" sperm. Immunogold labeling revealed human sperm cellular compartments containing PI3K, evidencing it in the head at both the membrane and nucleus and the entire tail, from the middle to the end piece of normal sperm. In varicocele PI3K label was confined to the head, with a strong reduction of specific reaction in the neck, middle piece, and tail. In conclusion, the data suggest that PI3K may play a role in the maintenance of male factor infertility associated with varicocele, and it may be further exploited as an additional molecular marker for the diagnosis of male infertility disorders.
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Infertilidade Masculina/enzimologia , Fosfatidilinositol 3-Quinase/análise , Espermatozoides/enzimologia , Varicocele/enzimologia , Biomarcadores/análise , Western Blotting , Estudos de Casos e Controles , Humanos , Imuno-Histoquímica , Infertilidade Masculina/etiologia , Infertilidade Masculina/patologia , Masculino , Microscopia Eletrônica de Transmissão , Valor Preditivo dos Testes , Análise do Sêmen/métodos , Espermatozoides/ultraestrutura , Varicocele/complicações , Varicocele/patologiaRESUMO
Multiple sclerosis (MS) is one of the most common neurodegenerative diseases showing various symptoms both of physical and cognitive type. In this work, we used attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy to analyze plasma samples for discriminating MS patients from healthy control individuals, and identifying potential spectral biomarkers helping the diagnosis through a quick non-invasive blood test. The cohort of the study consists of 85 subjects, including 45 MS patients and 40 healthy controls. The differences in the spectral features both in the fingerprint region (1800-900 cm-1) and in the high region (3050-2800 cm-1) of the infrared spectra were highlighted also with the support of different chemometric methods, to capture the most significant wavenumbers for the differentiation. The results show an increase in the lipid/protein ratio in MS patients, indicating changes in the level (metabolism) of these molecular components in the plasma. Moreover, the multivariate tools provided a promising rate of success in the diagnosis, with 78% sensitivity and 83% specificity obtained through the random forest model in the fingerprint region. The MS diagnostic tools based on biomarkers identification on blood (and blood component, like plasma or serum) are very challenging and the specificity and sensitivity values obtained in this work are very encouraging. Overall, the results obtained suggest that ATR-FTIR spectroscopy on plasma samples, requiring minimal or no manipulation, coupled with statistical multivariate approaches, is a promising analytical tool to support MS diagnosis through the identification of spectral biomarkers.
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Esclerose Múltipla , Plasma , Espectroscopia de Infravermelho com Transformada de Fourier , Humanos , Esclerose Múltipla/sangue , Esclerose Múltipla/diagnóstico , Análise Multivariada , Plasma/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Biomarcadores/sangueRESUMO
Autism Spectrum Disorder (ASD) is increasing, but its complete etiology is still lacking. Recently, application of ketogenic diet (KD) has shown to reduce abnormal behaviors while improving psychological/sociological status in neurodegenerative diseases. However, KD role on ASD and underlying mechanism remains unknown. In this work, KD administered to BTBR T+ Itpr3tf/J (BTBR) and C57BL/6J (C57) mice reduced social deficits (p = 0.002), repetitive behaviors (p < 0.001) and memory impairments (p = 0.001) in BTBR. Behavioral effects were related to reduced expression levels of tumor necrosis factor alpha, interleukin-1ß, and interleukin-6 in the plasma (p = 0.007; p < 0.001 and p = 0.023, respectively), prefrontal cortex (p = 0.006; p = 0.04 and p = 0.03) and hippocampus (p = 0.02; p = 0.09 and p = 0.03). Moreover, KD accounted for reduced oxidative stress by changing lipid peroxidation levels and superoxide dismutase activity in BTBR brain areas. Interestingly, KD increased relative abundances of putatively beneficial microbiota (Akkermansia and Blautia) in BTBR and C57 mice while reversing the increase of Lactobacillus in BTBR feces. Overall, our findings suggest that KD has a multifunctional role since it improved inflammatory plus oxidative stress levels together with remodeling gut-brain axis. Hence, KD may turn out be a valuable therapeutic approach for ameliorating ASD-like conditions even though more evidence is required to evaluate its effectiveness especially on a long term.
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Transtorno do Espectro Autista , Dieta Cetogênica , Microbiota , Camundongos , Animais , Transtorno do Espectro Autista/metabolismo , Camundongos Endogâmicos C57BL , Encéfalo/metabolismo , Modelos Animais de Doenças , Camundongos EndogâmicosRESUMO
Excessive fat and sugar intake represents a risk towards the development of different pathologies, such as obesity, diabetes, sociability and memory deficits. Although the adolescence stage is a susceptible period for these and other risks, effects of energy-dense nutrients in such an age period have not been fully investigated. In the present study, neurobehavioral alterations following a 4-week exposure to either normal diet (ND) or high-fat diet (HFD) plus normal water (NW) or liquid sugar (LS) were evaluated in young hamsters. HFD + LS and ND + LS significantly reduced food intake and water consumption, which was, in the latter group, almost completely substituted by LS. All obesogenic diets accounted for increased abdominal fat and liver weight with respect to body weight (p < 0.05-0.001). Additionally, glucose levels notably increased (p < 0.0001) together with insulin and triglycerides in HFD + LS (p < 0.001) and ND + LS (p < 0.01) while cholesterol displayed only a moderate increase (p < 0.05) in HFD + NW and HFD + LS. Animals fed with HFD and/or LS exhibited impaired social memory plus increased winning percentages (0.05 < p < 0.01) during the tube test. Interestingly, these same treatments led to a down-regulation of phosphorylated cAMP Response-Element Binding Protein (pCREB) in HFD + NW (p < 0.0001) for all areas, but rather was upregulated (p < 0.05) in ND + LS of the amygdala. Overall, in view of a brief exposure to palatable foods interfering with normal metabolic and social memory activities, the downregulation of pCREB constitutes a key indicator of neurobehavioral deficits during obesogenic diets. Compensatory mechanisms may be also occurring in the amygdala that strongly regulates emotional states via connections with other limbic areas.
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Dieta Hiperlipídica , Açúcares da Dieta , Comportamento Social , Gordura Abdominal , Agressão , Animais , Comportamento Animal , Peso Corporal , Córtex Cerebral/fisiopatologia , Cricetinae , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Dieta Hiperlipídica/efeitos adversos , Açúcares da Dieta/efeitos adversos , Fígado , Masculino , Transtornos da Memória , Tamanho do ÓrgãoRESUMO
Resistance to endocrine therapy is still a major clinical challenge in the management of estrogen receptor α-positive (ERα+) breast cancer (BC). Here, the role of the Forkhead box class O (FoxO)3a transcription factor in tumor progression has been evaluated in tamoxifen-resistant BC cells (TamR), expressing lower levels of FoxO3a compared to sensitive ones. FoxO3a re-expression reduces TamR motility (wound-healing and transmigration assays) and invasiveness (matrigel transwell invasion assays) through the mRNA (qRT-PCR) and protein (Western blot) induction of the integrin α5 subunit of the α5ß1 fibronectin receptor, a well-known membrane heterodimer controlling cell adhesion and signaling. The induction occurs through FoxO3a binding to a specific Forkhead responsive core sequence located on the integrin α5 promoter (cloning, luciferase, and ChIP assays). Moreover, FoxO3a failed to inhibit migration and invasion in integrin α5 silenced (siRNA) cells, demonstrating integrin α5 involvement in both processes. Finally, using large-scale gene expression data sets, a strong positive correlation between FoxO3a and integrin α5 in ERα+, but not in ER-negative (ERα-), BC patients emerged. Altogether, our data show how the oncosuppressor FoxO3a, by increasing the expression of its novel transcriptional target integrin α5, reverts the phenotype of endocrine-resistant BC toward a lower aggressiveness.
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At present, concerns are pointing to "tasteful" high-fat diets as a cause of conditioning physical-social states that through alterations of some key emotional- and nutritional-related limbic circuits such as hypothalamic and amygdalar areas lead to obesity states. Feeding and energetic homeostatic molecular mechanisms are part of a complex neuronal circuit accounting for this metabolic disorder. In an attempt to exclude conventional drugs for treating obesity, daidzein, a natural glycosidic isoflavone, which mimics estrogenic neuroprotective properties against increased body weight, is beginning to be preferred. In this study, evident anxiolytic-like behaviors were detected following treatment of high-fat diet hamsters with daidzein as shown by extremely evident (p < 0.001) exploration tendencies in novel object recognition test and a notably greater amount of time spent (p < 0.01) in open arms of elevated plus maze. Moreover, the isoflavone promoted a protective role against neurodegeneration processes as shown by few, if any, amino cupric silver granules in amygdalar, hypothalamic and hippocampal neuronal fields when compared with obese hamsters. Interestingly, elevated expression levels of the anorexic neuropeptide receptor neurotensin1 in the above limbic areas of obese hamsters were extremely reduced by daidzein, especially during recovery of cognitive events. Contextually, such effects were strongly paralleled by increased levels of the anti-neuroinflammatory cytokine, interleukin-10. Our results corroborate a neuroprotective ability of this natural glycosidic isoflavone, which through its interaction with the receptor neurotensin1 and interleukin-10 pathways is correlated not only to improved feeding states, and subsequently obesity conditions, but above all to cognitive performances.
Assuntos
Encéfalo/metabolismo , Interleucina-10/biossíntese , Isoflavonas/farmacologia , Nootrópicos/farmacologia , Obesidade/metabolismo , Receptores de Neurotensina/biossíntese , Animais , Encéfalo/efeitos dos fármacos , Cricetinae , Dieta Hiperlipídica/efeitos adversos , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Expressão Gênica , Isoflavonas/uso terapêutico , Mesocricetus , Nootrópicos/uso terapêutico , Obesidade/tratamento farmacológico , Obesidade/psicologia , Fitoestrógenos/farmacologia , Fitoestrógenos/uso terapêuticoRESUMO
BACKGROUND: Multiple sclerosis (MS) is frequently characterized by a variety of clinical signs, often exhibiting little specificity. The diagnosis requires a combination of medical observations and instrumental tests, and any support for its objective assessment is helpful. OBJECTIVE: Herein, we describe the application of thermal liquid biopsy (TLB) of blood plasma samples, a methodology for predicting the occurrence of MS with a noninvasive, quick blood test. METHODS: TLB allows one to define an index (TLB score), which provides information about overall real-time alterations in plasma proteome that may be indicative of MS. RESULTS: This pilot study, based on 85 subjects (45 MS patients and 40 controls), showed good performance indexes (sensitivity and specificity both around 70%). The diagnostic methods better discriminate between early stage and low-burden MS patients, and it is not influenced by gender, age, or assumption of therapeutic drugs. TLB is more accurate for patients having low disability level (≤ 3.0, measured by the expanded disability status scale, EDSS) and a relapsing-remitting diagnosis. CONCLUSION: Our results suggest that TLB can be applied to MS, especially in an initial phase of the disease when diagnosis is difficult and yet more important (in such cases, accuracy of prediction is close to 80%), as well as in personalized patient periodic monitoring. The next step will be determining its utility in differentiating between MS and other disorders, in particular in inflammatory diseases.
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Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental disorder featuring altered neuronal circuitry and consequently impaired social interactions, restrictive interests plus repetitive stereotypic activities. In the present study, differentiated behaviors of valproic (VPA) and propionic (PPA) acid-mediated autism rats were correlated to cerebral scaffolding proteins (Shank1,3) and BDNF expression variations. Sprague-Dawley offspring that received VPA during pregnancy displayed a notably diminished permanence (-78 %, p < 0.01) in the light chamber of light dark (LD) test, reduced exploratory tasks, i.e. grooming (-90 %) and rearing (-65 %). Moreover, they executed extremely greater climbing intervals (+300 %, p < 0.001) in novel cage (NC) test, plus exhibited an extremely reduced (-331 %) discrimination index in novel object recognition (NOR) test when compared to controls. PPA-treated postnatal days (PND) 12-16 rats also displayed anxiety-like behaviors, although in a less evident manner, as indicated by a moderate time (+55 %; p < 0.05) spent in dark chamber along with notable and moderate decreases in digging (-78 %) plus grooming (-52 %), respectively. Contextually, VPA- more than PPA supplied opposite Shank1,3 expression changes in cerebellum (CB; -62 %; +78 %), dorsomedial prefrontal cortex (DM-PFC; +95 % -76 %), respectively, while resulting extremely upregulated in hippocampus (HIP; +125 % - +155 %). Even BDNF resulted to be substantially and notably diminished in HIP (-85 %) and DM-PFC (-72 %), respectively, of VPA rats while it was only moderately reduced (-35 % to -45 %) in these same areas of PPA rats. The early altered brain-specific expression levels accounting for different behavioral performances may provide useful diagnostic indications and constitute valuable therapeutic strategies for autistic patients.
Assuntos
Transtorno Autístico/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Ansiedade/induzido quimicamente , Ansiedade/metabolismo , Transtorno Autístico/induzido quimicamente , Transtorno Autístico/psicologia , Western Blotting , Cérebro/efeitos dos fármacos , Cérebro/metabolismo , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Masculino , Teste de Campo Aberto , Propionatos/farmacologia , Ratos , Ratos Sprague-Dawley , Ácido Valproico/farmacologiaRESUMO
BACKGROUND: A wider biological role of 1alpha,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the active metabolite of vitamin D3, in tissues not primarily related to mineral metabolism was suggested. Recently, we evidenced the ultrastructural localization the 1,25(OH)2D3 receptor in the human sperm. However, the 1,25(OH)2D3 action in human male reproduction has not yet been clarified. METHODS AND RESULTS: By RT-PCR, Western blot and Immunofluorescence techniques, we demonstrated that human sperm expresses the 1,25(OH)2D3 receptor (VDR). Besides, 25(OH)D3-1 alpha-hydroxylase, evidenced by Western blot analysis, indicated that in sperm 1,25(OH)2D3 is locally produced, highlighting the potential for autocrine-paracrine responses. 1,25(OH)2D3 through VDR, increased intracellular Ca2+ levels, motility and acrosin activity revealing an unexpected significance of this hormone in the acquisition of fertilizing ability. In sperm, 1,25(OH)2D3 through VDR, reduces triglycerides content concomitantly to the increase of lipase activity. Rapid responses stimulated by 1,25(OH)2D3 have been observed on Akt, MAPK and GSK3 implying that this secosteroid is involved in different sperm signalling pathways. CONCLUSION: Our data extended the role of 1,25(OH)2D3 beyond its conventional physiological actions, paving the way for novel therapeutic opportunities in the treatment of the male reproduction disorders.
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Calcitriol/fisiologia , Células Germinativas/fisiologia , Receptores de Calcitriol/fisiologia , Espermatozoides/fisiologia , Acrosina/metabolismo , Acil-CoA Desidrogenase/metabolismo , Adulto , Western Blotting , Cálcio/metabolismo , Separação Celular , Ativação Enzimática/efeitos dos fármacos , Imunofluorescência , Células Germinativas/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Humanos , Técnicas In Vitro , Lipase/metabolismo , Masculino , RNA/biossíntese , RNA/isolamento & purificação , Receptores de Calcitriol/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/enzimologia , Espermatozoides/metabolismo , Triglicerídeos/metabolismoRESUMO
Human metapneumovirus (HMPV) is a recently described cause of respiratory infection. The purpose of this study was to to further the available information on the circulation of HMPV among young asymptomatic subjects. The epidemiology of HMPV was examined in a cohort of 73 university students during a winter season by using polymerase chain reaction. HPMV was detected in 3/73 (4.1%) asymptomatic subjects. Phylogenetic analysis has shown that circulating viruses belonged to different HMPV sublineages. Our findings indicate that asymptomatic carriage of HMPV might be a neglected source of viral transmission in the community.
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Metapneumovirus/genética , Infecções por Paramyxoviridae/epidemiologia , Adulto , Sequência de Bases , Estudos de Coortes , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Variação Genética , Humanos , Itália/epidemiologia , Masculino , Metapneumovirus/isolamento & purificação , Dados de Sequência Molecular , Infecções por Paramyxoviridae/complicações , Infecções por Paramyxoviridae/virologia , Filogenia , Infecções Respiratórias/etiologia , Universidades , Adulto JovemRESUMO
Iodine, a micronutrient that plays a pivotal role in thyroid hormone synthesis, is essential for proper health at all life stages. Indeed, an insufficient iodine intake may determine a thyroid dysfunction also with goiter, or it may be associated to clinical features such as stunted growth and mental retardation, referred as iodine deficiency disorders (IDDs). Iodine deficiency still remains an important public health problem in many countries, including Italy. The effective strategy for the prevention and control of IDDs is universal salt iodization, which was implemented in Italy in 2005 as a nationwide program adopted after the approval of an Italian law. Despite an improvement in the iodine intake, many regions in Italy are still characterized by mild iodine deficiency. In this review, we provide an overview of the historical evolution of the iodine status in the Calabria region, located in the South of Italy, during the past three decades. In particular, we have retraced an itinerary from the first epidemiological surveys at the end of the 1980s to the establishment of the Regional Observatory of Endemic Goiter and Iodine Prophylaxis, which represents an efficient model for the surveillance of IDDs and monitoring the efficacy of iodine prophylaxis.
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Bócio Endêmico/epidemiologia , Bócio Endêmico/prevenção & controle , Iodo/administração & dosagem , Iodo/farmacologia , Cloreto de Sódio na Dieta/administração & dosagem , Humanos , Itália/epidemiologia , Estudos RetrospectivosRESUMO
Background: Resistance to endocrine treatments is a major clinical challenge in the management of estrogen receptor positive breast cancers. Although multiple mechanisms leading to endocrine resistance have been proposed, the poor outcome of this subgroup of patients demands additional studies. Methods: FoxO3a involvement in the acquisition and reversion of tamoxifen resistance was assessed in vitro in three parental ER+ breast cancer cells, MCF-7, T47D and ZR-75-1, in the deriving Tamoxifen resistant models (TamR) and in Tet-inducible TamR/FoxO3a stable cell lines, by growth curves, PLA, siRNA, RT-PCR, Western blot, Immunofluorescence, Transmission Electron Microscopy, TUNEL, cell cycle, proteomics analyses and animal models. FoxO3a clinical relevance was validated in silico by Kaplan-Meier survival curves. Results: Here, we show that tamoxifen resistant breast cancer cells (TamR) express low FoxO3a levels. The hyperactive growth factors signaling, characterizing these cells, leads to FoxO3a hyper-phosphorylation and subsequent proteasomal degradation. FoxO3a re-expression by using TamR tetracycline inducible cells or by treating TamR with the anticonvulsant lamotrigine (LTG), restored the sensitivity to the antiestrogen and strongly reduced tumor mass in TamR-derived mouse xenografts. Proteomics data unveiled novel potential mediators of FoxO3a anti-proliferative and pro-apoptotic activity, while the Kaplan-Meier analysis showed that FoxO3a is predictive of a positive response to tamoxifen therapy in Luminal A breast cancer patients. Conclusions: Altogether, our data indicate that FoxO3a is a key target to be exploited in endocrine-resistant tumors. In this context, LTG, being able to induce FoxO3a, might represent a valid candidate in combination therapy to prevent resistance to tamoxifen in patients at risk.
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Recent indications are suggesting that high fat and sugar-enriched foods do not only evoke harmful physiological conditions, but they also endure evident structural alterations in cerebral regions controlling cognitive and feeding behaviors. Food consumption plus neuronal energy regulatory mechanisms seem to constitute a complex system assuring that food calories do not exceed body requirements. At the same time obesogenic-related properties of limbic feeding stations like the hypothalamus (HTH), hippocampus (HIP) and amygdala (AMY) tend to control eating habits through the interaction of distinct neuropeptides. For this purpose, it was our intention to correlate expression differences of a key anti-obesogenic neuropeptide receptor i.e. neurotensin1 (NTR1) on mnemonic performances in the hibernating hamster (Mesocricetus auratus) exposed to a high fat diet (HFD). Interestingly, these hamsters exhibited a notable enhanced (pâ¯<â¯0.01) body weight from the fifth on to the twelfth week of treatment, which was accompanied by elevated blood lipid cholesterolo and triglycerides and glucose levels. At the same time these hamsters provided diminished locomotor activities such as exploratory bouts, rearing and grooming behaviors. Of greater relevance was their very extreme (pâ¯<â¯0.001) inability of identifying new objects during novel object recognition (NOR) tests along with not having correctly chosen the chamber of the conditioned place preference (CPP) apparatus, which contained the gratifying reward. Surprisingly the altered behavioral plus mnemonic tasks of HFD hamsters were tightly related to elevated NTR1 expression changes in the above limbic sites thus proposing this neuronal system as a highly probable alternative for treating obesity-dependent mnemonic dysfunctions.
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Dieta Hiperlipídica/efeitos adversos , Aprendizagem , Reconhecimento Psicológico , Recompensa , Tecido Adiposo , Animais , Glicemia , Peso Corporal , Comportamento Exploratório , Asseio Animal , Aprendizagem/fisiologia , Sistema Límbico/metabolismo , Lipídeos/sangue , Masculino , Mesocricetus , Atividade Motora , Distribuição Aleatória , Receptores de Neurotensina/metabolismo , Reconhecimento Psicológico/fisiologiaRESUMO
BACKGROUND: Increased levels of malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are demonstrated in plasma of uremic patients. A study showed that the comparison of erythrocytes of healthy and diseased patients (obese, hypertensive, and Type 2 diabetics) with age is associated to a disturbed oxidant/antioxidant balance when obesity is associated with hypertension. 4-hydroxytyrosol is shown to significantly protect red blood cells (RBCs) from oxidative damage (4-HNE). In literature, there are partial discussions on the role of lipids and their oxidation products. The products of degradation of membrane proteins are observed as self-consisting products without interrelations with membrane lipids. OBJECTIVE: The aim of this study is to evaluate the role of polyunsaturated fatty acid (PUFA) metabolites on oxidative damage (4-hydroxy-alkenals) in RBCs of hypertriglyceridemic patients after membrane treatment with 4-hydroxytyrosol. MATERIALS AND METHODS: The authors optimize the isolation of RBC ghosts and spectrophotometric method to measure free 4-hydroxyalkenals in human RBC membranes and investigated the effect on oxidative damage in human erythrocyte membranes and in vitro 4-hydroxytyrosol treatment to evaluate the membrane lipids reducible by this phenol. RESULTS: Plasma triglyceride levels in patients are clearly higher than in controls. Moreover, total membrane proteins data are similar to previous described. The normalized alkenals levels are significantly enhanced in hyperlipemic patients in comparison to normoglyceridemic controls. After the 4-hydroxytyrosol action, lipid metabolites substantially decrease. The ratio of oxidized lipids (MDA + HNE) and membrane proteins data are similar to previously described ones. CONCLUSION: According to experimental data, the accumulation of the alkenals in RBC membrane could be produced either by partial PUFA oxidation contained in glycerides and plasma glycerides and by glycerides into plasma membrane recycled RBC. SUMMARY: Hypertriglyceridemia induces oxidative stress in human red blood cell (RBC) membranesOxidative stress causes increased plasma membrane total protein concentration and hydroxynonenal and malondialdehyde levelsThe authors optimize the isolation of RBC ghosts and spectrophotometric method to measure free 4-hydroxyalkenals in human RBC membranesAfter the reduction with 4-hydroxytyrosol, oxidized lipid concentration significantly decrease. Abbreviations used: RBC: Red blood cell; MDA: Malondialdehyde; HNE\HAE: 4-hydroxyalkenals; LPO: Lipid peroxidation; ROS: Reactive oxygen species; ORAC: Oxygen Radical Absorbance Capacity.
RESUMO
A paucity of information is available on the activity of protease inhibitors (PI) in chronically-infected monocyte-derived macrophages (MDM) and on the kinetics of viral-rebound after PI removal in vitro. To fill this gap, the activity of different concentrations of amprenavir (AMP) was evaluated in chronically-infected MDM by measuring p24-production every day up to 12 days after drug administration and up to seven days after drug removal. Clinically-relevant concentrations of AMP (4 and 20 µM) drastically decreased p24 amount released from chronically-infected MDM from Day 2 up to Day 12 after drug administration. The kinetics of viral-rebound after AMP-removal (4 and 20 µM) showed that, despite an initial increase, p24-production over time never reached the level observed for untreated-MDM, suggesting a persistent intracellular drug activity. In line with this, after AMP-removal, human immunodeficiency virus 1 (HIV-1) infectivity and intracellular the p24/p55 ratio (reflecting virion-maturation) were remarkably lower than observed for untreated MDM. Overall, AMP shows high efficacy in blocking HIV-1 replication in chronically-infected MDM, persisting even after drug-removal. This highlights the role of protease inhibitors in preventing the establishment of this important HIV-1 reservoir, thus reducing viral-dissemination in different anatomical compartments.
Assuntos
Carbamatos/farmacologia , Inibidores da Protease de HIV/farmacologia , HIV-1/efeitos dos fármacos , Macrófagos/virologia , Monócitos/virologia , Sulfonamidas/farmacologia , Replicação Viral/efeitos dos fármacos , Células Cultivadas , Furanos , HIV-1/fisiologia , HumanosRESUMO
Local estrogen production from aromatase-mediated conversion of androgens is an important mechanism of autocrine growth stimulation in hormone-dependent breast cancers. The control mechanism of aromatase enzymatic activity in recent years has been demonstrated to be more complex than previously identified. Indeed, it is well known that aromatase expression is regulated at the transcriptional level through the alternative use of tissue-specific promoters, whereas it has become clear that the activity of this enzyme is also controlled by post-transcriptional modifications, such as phosphorylation processes. This paper presents a selective review of the novel findings in this area showing phosphorylation/dephosphorylation of aromatase as a switch to rapidly modulate its enzymatic activity. Particularly, we describe studies conducted in our laboratories, focusing on the role of estrogens in modulating aromatase activity in estrogen-dependent breast cancer cells. Two separate mechanisms are described. First, 17ß-estradiol (E2), through c-Src kinase, is able to enhance tyrosine phosphorylation levels of aromatase protein and increases its enzymatic activity and estrogen biosynthesis. Secondly, E2, through the activation of PI3K/Akt pathway, impairs the ability of the tyrosine phosphatase PTP1B to dephosphorylate aromatase, resulting in a consequent enhanced phosphorylation and activity of the aromatase protein itself. These new controls of aromatase function provide insights into the mechanisms through which local estrogen production can be altered in breast cancer tissues. They also offer a vast array of possibilities for identifying different cell signalings that should be targeted in novel therapeutic strategies for breast cancer treatment.