ORESTES VICENTE FORLENZA
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Psiquiatria, Faculdade de Medicina - Docente
LIM/27 - Laboratório de Neurociências, Hospital das Clínicas, Faculdade de Medicina
LIM/27 - Laboratório de Neurociências, Hospital das Clínicas, Faculdade de Medicina
140 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 140
- Cognitive Reserve Relates to Functional Network Efficiency in Alzheimer's Disease(2018) WEILER, Marina; CASSEB, Raphael Fernandes; CAMPOS, Brunno Machado de; TEIXEIRA, Camila Vieira de Ligo; CARLETTI-CASSANI, Ana Flavia Mac Knight; VICENTINI, Jessica Elias; MAGALHAES, Thamires Naela Cardoso; ALMEIRA, Debora Queiroz de; TALIB, Leda Leme; FORLENZA, Orestes Vicente; BALTHAZAR, Marcio Luiz Figueredo; CASTELLANO, GabrielaAlzheimer's disease (AD) is the most common form of dementia, with no means of cure or prevention. The presence of abnormal disease-related proteins in the population is, in turn, much more common than the incidence of dementia. In this context, the cognitive reserve (CR) hypothesis has been proposed to explain the discontinuity between pathophysiological and clinical expression of AD, suggesting that CR mitigates the effects of pathology on clinical expression and cognition. fMRI studies of the human connectome have recently reported that AD patients present diminished functional efficiency in resting-state networks, leading to a loss in information flow and cognitive processing. No study has investigated, however, whether CR modifies the effects of the pathology in functional network efficiency in AD patients. We analyzed the relationship between CR, pathophysiology and network efficiency, and whether CR modifies the relationship between them. Fourteen mild AD, 28 amnestic mild cognitive impairment (aMCI) due to AD, and 28 controls were enrolled. We used education to measure CR, cerebrospinal fluid (CSF) biomarkers to evaluate pathophysiology, and graph metrics to measure network efficiency. We found no relationship between CR and CSF biomarkers; CR was related to higher network efficiency in all groups; and abnormal levels of CSF protein biomarkers were related to more efficient networks in the AD group. Education modified the effects of tau-related pathology in the aMCI and mild AD groups. Although higher CR might not protect individuals from developing AD pathophysiology, AD patients with higher CR are better able to cope with the effects of pathology-presenting more efficient networks despite pathology burden. The present study highlights that interventions focusing on cognitive stimulation might be useful to slow age-related cognitive decline or dementia and lengthen healthy aging.
- Evaluation of 10-minute post-injection 11C-PiB PET and its correlation with 18F-FDG PET in older adults who are cognitively healthy, mildly impaired, or with probable Alzheimer's disease(2022) CARNEIRO, Camila de Godoi; FARIA, Daniele de Paula; COUTINHO, Artur Martins; ONO, Carla Rachel; DURAN, Fabio Luis de Souza; COSTA, Naomi Antunes da; GARCEZ, Alexandre Teles; SILVEIRA, Paula Squarzoni da; FORLENZA, Orestes Vicente; BRUCKI, Sonia Maria Dozzi; NITRINI, Ricardo; FILHO, Geraldo Busatto; BUCHPIGUEL, Carlos AlbertoObjective: Positron emission tomography (PET) allows in vivo evaluation of molecular targets in neurodegenerative diseases, such as Alzheimer's disease. Mild cognitive impairment is an intermediate stage between normal cognition and Alzheimer-type dementia. In vivo fibrillar amyloid-beta can be detected in PET using [11C]-labeled Pittsburgh compound B (11C-PiB). In contrast, [18F] fluoro-2-deoxy-d-glucose (18F-FDG) is a neurodegeneration biomarker used to evaluate cerebral glucose metabolism, indicating neuronal injury and synaptic dysfunction. In addition, early cerebral uptake of amyloid-PET tracers can determine regional cerebral blood flow. The present study compared early-phase 11C-PiB and 18F-FDG in older adults without cognitive impairment, amnestic mild cognitive impairment, and clinical diagnosis of probable Alzheimer's disease.Methods: We selected 90 older adults, clinically classified as healthy controls, with amnestic mild cognitive impairment, or with probable Alzheimer's disease, who underwent an 18F-FDG PET, early -phase 11C-PiB PET and magnetic resonance imaging. All participants were also classified as amyloid-positive or-negative in late-phase 11C-PiB. The data were analyzed using statistical parametric mapping.Results: We found that the probable Alzheimer's disease and amnestic mild cognitive impairment group had lower early-phase 11C-PiB uptake in limbic structures than 18F-FDG uptake. The images showed significant interactions between amyloid-beta status (negative or positive). However, early -phase 11C-PiB appears to provide different information from 18F-FDG about neurodegeneration.Conclusions: Our study suggests that early-phase 11C-PiB uptake correlates with 18F-FDG, irrespective of the particular amyloid-beta status. In addition, we observed distinct regional distribution patterns between both biomarkers, reinforcing the need for more robust studies to investigate the real clinical value of early-phase amyloid-PET imaging.
- Brief screening for mild cognitive impairment: validation of the Brazilian version of the Montreal cognitive assessment(2013) MEMORIA, Claudia M.; YASSUDA, Monica S.; NAKANO, Eduardo Y.; FORLENZA, Orestes V.Background The Montreal Cognitive Assessment (MoCA) is a brief cognitive schedule that has been developed for the screening of patients with Mild Cognitive Impairment (MCI). MCI is recognized as a high-risk state for Alzheimer's disease. The aim of the present study is to examine the reliability and validity of the Brazilian version of the MoCA test (MoCA-BR) in a sample of older individuals with at least 4?years of education. Methods The MoCA-BR was administered to 112 older adults who were classified into three diagnostic groups according to their cognitive state (Alzheimer's disease, n?=?28; MCI, n?=?43; normal controls, n?=?41). This procedure was based on clinical and neuropsychological data. The performance in the MoCA-BR was compared with the Mini-mental state examination (MMSE) and the Cambridge Cognitive Examination. Diagnostic accuracy was examined with the receiver operating characteristic (ROC) curve analyses. Results Cronbach's alpha for the MoCA-BR was 0.75. Temporal stability (retesting after 3?months) using intraclass correlation coefficient was 0.75 (p?
- Lower Cerebrospinal Fluid Concentration of Brain-Derived Neurotrophic Factor Predicts Progression from Mild Cognitive Impairment to Alzheimer's Disease(2015) FORLENZA, Orestes Vicente; DINIZ, Breno Satler; TEIXEIRA, Antonio Lucio; RADANOVIC, Marcia; TALIB, Leda Leme; ROCHA, Natalia Pessoa; GATTAZ, Wagner FaridThere is little information on the dynamics of BDNF in the CSF in the continuum between healthy aging, MCI and AD. We included 128 older adults (77 with amnestic MCI, 26 with AD and 25 healthy controls). CSF BDNF level was measured by ELISA assay, and AD biomarkers (A beta(42), T-Tau and P-Tau(181)) were measured using a Luminex xMAP assay. CSF BDNF levels were significantly reduced in AD subjects compared to MCI and healthy controls (p = 0.009). Logistic regression models showed that lower CSF BDNF levels (p = 0.008), lower CSF A beta(42) (p = 0.005) and lower MMSE scores (p = 0.007) are significantly associated with progression from MCI to AD. The present study adds strong evidence of the involvement of BDNF in the pathophysiology of neurodegenerative changes in AD. Interventions aiming to restore central neurotrophic support may represent future therapeutic targets to prevent or delay the progression from MCI to AD.
- Mitochondrial dysfunction in Alzheimer's disease: Therapeutic implications of lithium(2021) SINGULANI, Monique P.; PAULA, Vanessa J. R. De; FORLENZA, Orestes V.Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases, characterized by the accumulation of abnormal tau proteins within neurons and amyloid plaques in the brain parenchyma, which leads to progressive loss of neurons in the brain. While the detailed mechanism of the pathogenesis of AD is still unknown, evidence suggests that mitochondrial dysfunction likely plays a fundamental role in the pathogenesis of this disease. Due to the relevance of mitochondrial alterations in AD, recent works have suggested the therapeutic potential of mitochondrial-targeted lithium. Lithium has been shown to possess neuroprotective and neurotrophic properties that could also be related to the upregulation of mitochondrial function. In the current work, we perform a comprehensive investigation of the significance of mitochondrial dysfunction in AD and pharmacological treatment with lithium as imperative in this pathology, through a brief review of the major findings on the effects of lithium as a therapeutic approach targeting mitochondria in the context of AD.
- Is cerebral microbleed prevalence relevant as a biomarker in amnestic mild cognitive impairment and mild Alzheimer's disease?(2017) RABELO, A. G. B.; TEIXEIRA, C. V. L.; MAGALHAES, T. N. C.; CARLETTI-CASSANI, A. F. M. K.; AMATO FILHO, A. C. S.; JOAQUIM, H. P. G.; TALIB, L. L.; FORLENZA, O.; RIBEIRO, P. A. O.; SECOLIN, R.; LOPES-CENDES, I.; CENDES, F.; BALTHAZAR, M. L. F.Introduction The search for a reliable neuroimaging biomarker in Alzheimer's disease is a matter of intense research. The presence of cerebral microbleeds seems to be a potential biomarker. However, it is not clear if the presence of microbleeds has clinical usefulness to differentiate mild Alzheimer's disease and amnestic mild cognitive impairment from normal aging. We aimed to verify if microbleed prevalence differs among three groups: mild Alzheimer's disease, amnestic mild cognitive impairment due to Alzheimer's disease, and normal controls. Moreover, we studied whether microbleeds were associated with apolipoprotein E allele ϵ4 status, cerebrospinal fluid amyloid-beta, total and phosphorylated tau protein levels, vascular factors, and cognition. Methods Twenty-eight mild Alzheimer's disease patients, 34 with amnestic mild cognitive impairment and 36 cognitively normal elderly subjects underwent: magnetic resonance imaging with a susceptibility-weighted imaging sequence on a 3T scanner, apolipoprotein E genotyping and a full neuropsychological evaluation. Only amnestic mild cognitive impairment and mild Alzheimer's disease underwent cerebrospinal fluid analysis. We compared the groups and verified if microbleeds were predicted by all other variables. Results Mild Alzheimer's disease presented a higher prevalence of apolipoprotein E allele ϵ4 in relation to amnestic mild cognitive impairment and control group. No significant differences were found between groups when considering microbleed presence. Logistic regression tests failed to find any relationship between microbleeds and the variables. We performed three different regression models using different independent variables: Model 1 - amyloid-beta, phosphorylated tau protein, total tau, apolipoprotein E allele ϵ4 status, age, and sex; Model 2 - vascular risk factors, age, and sex; Model 3 - cognitive scores sex, age, and education. Conclusion Although microbleeds might be related to the Alzheimer's disease process, their presence is not a good candidate for a neuroimaging biomarker of the disease, especially in its early phases. © 2017 SAGE Publications.
- Sentence processing in mild cognitive impairment(2022) PEREIRA, Diana Nakamura; SOUZA, Wellington da Cruz; BELAN, Ariella Fornachari Ribeiro; CAMARGO, Marina von Zuben de Arruda; FORLENZA, Orestes Vicente; RADANOVIC, MarciaDifficulties in sentence processing have been reported in patients with Mild Cognitive Impairment (MCI), which may be due to impairment in primary syntactic abilities or short-term memory. In the present study, we investigated the relationship between overt sentence production (SP) and comprehension (SC) with short-term memory performance in MCI. Cognitively healthy elderly (n = 34), amnestic MCI (aMCI,n = 22), non-amnestic MCI (naMCI,n = 45), and Alzheimer's disease (AD,n = 18) patients were asked to complete tests of constrained SP and oral SC. We tested the association between performance in SP and SC with memory tasks and performed a qualitative analysis of the frequency and type of errors in SC. Our results showed that there were no intergroup differences in SC and SP performances. SC scores were associated with delayed recall for words in the naMCI group (p = 0.003), and immediate (p = 0.001) and delayed recall for shapes (p = 0.031) in AD. There were no predictors for NAT scores in any group. In conclusion, the three groups performed similarly in SC and SP tasks. Short-term memory was not associated with performance in the SP task. There was an association between performance in the SC task and verbal memory in naMCI and non-verbal memory in AD; the latter may reflect visuospatial processing demands embedded in the SC task.
- Clinical and biological effects of long-term lithium treatment in older adults with amnestic mild cognitive impairment: randomised clinical trial(2019) FORLENZA, Orestes V.; RADANOVIC, Marcia; TALIB, Leda L.; GATTAZ, Wagner F.Background Experimental studies indicate that lithium may facilitate neurotrophic/protective responses in the brain. Epidemiological and imaging studies in bipolar disorder, in addition to a few trials in Alzheimer's disease support the clinical translation of these findings. Nonetheless, there is limited controlled data about potential use of lithium to treat or prevent dementia. Aims To determine the benefits of lithium treatment in patients with amnestic mild cognitive impairment (MCI), a clinical condition associated with high risk for Alzheimer's disease. Method A total of 61 community-dwelling, physically healthy, older adults with MCI were randomised to receive lithium or placebo (1:1) for 2 years (double-blind phase), and followed-up for an additional 24 months (single-blinded phase) (trial registration at clinicaltrials.gov: NCT01055392). Lithium carbonate was prescribed to yield subtherapeutic concentrations (0.25-0.5 mEq/L). Primary outcome variables were the cognitive (Alzheimer's Disease Assessment Scale - cognitive subscale) and functional (Clinical Dementia Rating - Sum of Boxes) parameters obtained at baseline and after 12 and 24 months. Secondary outcomes were neuropsychological test scores; cerebrospinal fluid (CSF) concentrations of Alzheimer's disease-related biomarkers determined at 0, 12 and 36 months; conversion rate from MCI to dementia (0-48 months). Results Participants in the placebo group displayed cognitive and functional decline, whereas lithium-treated patients remained stable over 2 years. Lithium treatment was associated with better performance on memory and attention tests after 24 months, and with a significant increase in CSF amyloid-beta peptide (A beta(1-42)) after 36 months. Conclusions Long-term lithium attenuates cognitive and functional decline in amnestic MCI, and modifies Alzheimer's disease-related CSF biomarkers. The present data reinforces the disease-modifying properties of lithium in the MCI-Alzheimer's disease continuum. Declaration of interest None.
- Heterogeneity of Cerebrospinal Fluid Biomarkers Profiles in Individuals with Distinct Levels of Cognitive Decline: A Cross-Sectional Study(2021) PAIS, Marcos; LOUREIRO, Julia; VALE, Vagner do; RADANOVIC, Marcia; TALIB, Leda; STELLA, Florindo; FORLENZA, OrestesBackground: Decreased cerebrospinal fluid (CSF) concentrations of the amyloid-beta (A beta), along with increased total (T-tau) and phosphorylated tau protein (P-tau), are widely accepted as core biomarkers of Alzheimer's disease (AD) pathology. Nonetheless, there are a few remaining caveats that still preclude the full incorporation of AD biomarkers into clinical practice. Objective: To determine the frequency of clinical-biological mismatches in a clinical sample of older adults with varying degrees of cognitive impairment. Methods: 204 participants were enrolled for a cross-sectional assessment and allocated into diagnostic groups: probable AD (n = 60, 29.4%); MCI (n = 84, 41.2%); or normal cognition (NC, n = 60, 29.4%). CSF concentrations of A beta(42), T-tau, and (181)Thr-P-tau were determined, and A beta(42)/P-tau ratio below 9.53 was used as a proxy of AD pathology. The AT(N) classification was further used as a framework to ascertain the biological evidence of AD. Results: The majority (73.7%) of patients in the AD group had the A beta(42)/P-tau ratio below the cut-off score for AD, as opposed to a smaller proportion in the MCI (42.9%) and NC (23.3%) groups. In the latter, 21 subjects (35%) were classified as A+, 28 (46.7%) as T+, and 23 (38.3%) as N+. In the AD group, 66.7% of the cases were classified as A+, 78.3% as T+, and 80% as N+. Conclusion: Analysis of CSF biomarkers was able to discriminate between AD, MCI, and NC. However, clinical-biological mismatches were observed in a non-negligible proportion of cases.
- Regulation of leukocyte tricarboxylic acid cycle in drug-naive Bipolar Disorder(2015) SOUSA, Rafael T. de; STRECK, Emilio L.; FORLENZA, Orestes V.; BRUNONI, Andre R.; ZANETTI, Marcus V.; FERREIRA, Gabriela K.; DINIZ, Breno S.; PORTELA, Luis V.; CARVALHO, Andre F.; ZARATE JR., Carlos A.; GATTAZ, Wagner F.; MACHADO-VIEIRA, RodrigoSeveral lines of evidence suggest a role for mitochondrial dysfunction in the pathophysiology of bipolar disorder (BD). The tricarboxylic acid cycle (TCA cycle) is fundamental for mitochondrial energy production and produces substrates used in oxidative phosphorylation by the mitochondrial electron transport chain. The activity of the key TCA cycle enzymes citrate synthase, malate dehydrogenase, and succinate dehydrogenase has never been evaluated in BD. In the present study, these enzymes were assayed from leukocytes of drug-naive BD patients in a major depressive episode (n = 18) and compared to 24 age-matched healthy controls. Drug-naive BD patients did not show differences in activities of citrate synthase (p = 0.79), malate dehydrogenase (p = 0.17), and succinate dehydrogenase (p = 0.35) compared with healthy controls. No correlation between any TCA cycle enzyme activity and severity of depressive symptoms was observed. Overall, these data suggest that the activities of the TCA cycle enzymes are not altered in major depressive episodes of recent-onset BD, which may support the concept of illness staging and neuroprogression in BD.