LEDA LEME TALIB
Projetos de Pesquisa
Unidades Organizacionais
Instituto de Psiquiatria, Hospital das Clínicas, Faculdade de Medicina
LIM/27 - Laboratório de Neurociências, Hospital das Clínicas, Faculdade de Medicina
LIM/27 - Laboratório de Neurociências, Hospital das Clínicas, Faculdade de Medicina
15 resultados
Resultados de Busca
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- 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.
- 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.
- Decision tree-based classification as a support to diagnosis in the Alzheimer's disease continuum using cerebrospinal fluid biomarkers: insights from automated analysis(2022) COSTA, Alana; PAIS, Marcos; LOUREIRO, Julia; STELLA, Florindo; RADANOVIC, Marcia; GATTAZ, Wagner; FORLENZA, Orestes; TALIB, LedaObjective: Cerebrospinal fluid (CSF) biomarkers add accuracy to the diagnostic workup of cognitive impairment by illustrating Alzheimer's disease (AD) pathology. However, there are no universally accepted cutoff values for the interpretation of AD biomarkers. The aim of this study is to determine the viability of a decision-tree method to analyse CSF biomarkers of AD as a support for clinical diagnosis. Methods: A decision-tree method (automated classification analysis) was applied to concentrations of AD biomarkers in CSF as a support for clinical diagnosis in older adults with or without cognitive impairment in a Brazilian cohort. In brief, 272 older adults (68 with AD, 122 with mild cognitive impairment [MCI], and 82 healthy controls) were assessed for CSF concentrations of A beta(1-42), total-tau, and phosphorylated-tau using multiplexed Luminex assays; biomarker values were used to generate decision-tree algorithms (classification and regression tree) in the R statistical software environment. Results: The best decision tree model had an accuracy of 74.65% to differentiate the three groups. Cluster analysis supported the combination of CSF biomarkers to differentiate AD and MCI vs. controls, suggesting the best cutoff values for each clinical condition. Conclusion: Automated analyses of AD biomarkers provide valuable information to support the clinical diagnosis of MCI and AD in research settings.
- Correlation between CSF biomarkers of Alzheimer's disease and global cognition in a psychogeriatric clinic cohort(2019) RADANOVIC, Marcia; OSHIRO, Carlos A.; FREITAS, Thiago Q.; TALIB, Leda L.; FORLENZA, Orestes V.Objective: The relationship between biomarkers of amyloid-beta aggregation (A beta(1-42)) and/or neurodegeneration (Tau protein) in cerebrospinal fluid (CSF) and cognitive decline is still unclear. We aimed to ascertain whether CSF biomarkers correlate with cognitive performance in healthy and cognitively impaired subjects, starting from clinical diagnoses. Methods: We tested for correlation between CSF biomarkers and Mini-Mental State Examination (MMSE) scores in 208 subjects: 54 healthy controls, 82 with mild cognitive impairment (MCI), 46 with Alzheimer's disease (AD), and 26 with other dementias (OD). Results: MMSE correlated weakly with all CSF biomarkers in the overall sample (r = 0.242, p < 0.0006). A beta(1-42) and MMSE correlated weakly in MCI (r = 0.247, p = 0.030), and moderately in OD (r = 0.440, p = 0.027). t-Tau showed a weak inverse correlation with MMSE in controls (r = -0.284, p = 0.043) and MCI (r = -0.241, p = 0.036), and a moderate/strong correlation in OD (r = 0.665), p = 0.0003). p-Tau correlated weakly with MMSE in AD (r = -0.343, p = 0.026) and moderately in OD (r = -0.540, p = 0.0005). The A beta(1-42)/p-Tau ratio had a moderate/strong correlation with MMSE in OD (r = 0.597, p = 0.001). Conclusion: CSF biomarkers correlated best with cognitive performance in OD. t-Tau correlated weakly with cognition in controls and patients with MCI. In AD, only p-Tau levels correlated with cognitive performance. This pattern, which has been reported previously, seems to indicate that CSF biomarkers might not be reliable as indicators of disease severity.
- Cognitive impairment in late-life bipolar disorder is not associated with Alzheimer's disease pathological signature in the cerebrospinal fluid(2016) FORLENZA, Orestes V.; APRAHAMIAN, Ivan; RADANOVIC, Marcia; TALIB, Leda L.; CAMARGO, Marina Z. A.; STELLA, Florindo; MACHADO-VIEIRA, Rodrigo; GATTAZ, Wagner F.ObjectivesCognitive impairment is a common feature of late-life bipolar disorder (BD). Yet, there is limited information on the biological mechanisms associated with this process. It is uncertain whether cognitively impaired patients with BD may present the Alzheimer's disease (AD) bio-signature in the cerebrospinal fluid (CSF), defined as a combination of low concentrations of the amyloid-beta peptide (A(1-42)) and high concentrations of total tau (T-tau) and tau phosphorylated at threonine 181 (P-tau). In this study, we sought to determine whether cognitive impairment in elderly patients with BD is associated with the AD CSF bio-signature. MethodsSeventy-two participants were enrolled in the study. The test group comprised older adults with BD and mild cognitive impairment (BD-MCI; n=16) and the comparison groups comprised patients with dementia due to AD (n=17), patients with amnestic MCI (aMCI; n=14), and cognitively healthy older adults (control group; n=25). CSF samples were obtained by lumbar puncture and concentrations of A(1-42), T-tau and P-tau were determined. ResultsCSF concentrations of all biomarkers were significantly different in the AD group compared to all other groups, but did not differentiate BD-MCI subjects from aMCI subjects and controls. BD-MCI patients had a non-significant reduction in CSF A(1-42) compared to controls, but this was still higher than in the AD group. Concentrations of T-tau and P-tau in BD-MCI patients were similar to those in controls, and significantly lower than those in AD. ConclusionsCognitively impaired patients with BD do not display the so-called AD bio-signature in the CSF. We therefore hypothesize that cognitive deterioration in BD is not associated with the classical pathophysiological mechanisms observed in AD, i.e., amyloid deposition and hyperphosphorylation of microtubule-associated tau protein.
- Reduced Cerebrospinal Fluid Levels of Brain-Derived Neurotrophic Factor Is Associated With Cognitive Impairment in Late-Life Major Depression(2014) DINIZ, Breno S.; TEIXEIRA, Antonio L.; MACHADO-VIEIRA, Rodrigo; TALIB, Leda L.; RADANOVIC, Marcia; GATTAZ, Wagner F.; FORLENZA, Orestes V.Objectives. Late-life depression (LLD) is associated with reduced neurotrophic support and abnormalities in neurodegenerative cascades. The aim of the present study is to determine the concentrations of brain-derived neurotrophic factor (BDNF), amyloid-beta(42), total Tau, and phosphorylated Tau in the cerebrospinal fluid (CSF) of patients with LLD and cognitive impairment compared to healthy older adults. Method. We included 25 antidepressant-free patients with LLD (10 with mild cognitive impairment [LLD + MCI] and 15 with no cognitive decline [LLD + NCD]) and 25 healthy older adults as a comparison group. Depressive symptoms were assessed by the 21-item Hamilton Depression Rating Scale (HDRS-21) and cognitive performance by a comprehensive cognitive battery. Results. Patients with LLD + MCI showed significantly lower CSF BDNF levels compared to LLD + NCD and healthy controls (p = .003). There were no significant differences in Alzheimer's disease-related CSF biomarkers between groups. CSF BDNF concentrations were positively correlated with Cambridge Cognitive Test (CAMCOG) scores (r = .36, p = .02). Discussion. The present study adds to the growing body of evidence that abnormalities in the BDNF system are involved in the pathophysiology of LLD. The reduction of the availability of BDNF in the central nervous system may indicate increased vulnerability to the development of several age-related neuropsychiatric disorders as well as to adverse cognitive outcomes.
- Increased CSF levels of total Tau in patients with subcortical cerebrovascular pathology and cognitive impairment(2017) RADANOVIC, Márcia; STELLA, Florindo; SILVA, Lis Gomes; TALIB, Leda L.; FORLENZA, Orestes V.ABSTRACT. Cognitive impairment includes mild cognitive decline and dementia, such as Alzheimer's disease (AD) and cerebrovascular-related pathologies. Objective: To investigate the profile of AD-related CSF biomarkers in a sample of cognitively impaired and unimpaired older adults with concomitant subcortical cerebrovascular burden. Methods: Seventy-eight older adults attending an outpatient psychogeriatric clinic were enrolled. Diagnoses were based on clinical, neuropsychological, laboratory, and neuroimaging data. Participants were classified into: cognitively normal (controls, n = 30), mild cognitive impairment (MCI, n = 34), and dementia (AD, n = 14). All subjects were submitted to CSF analyses for determination of amyloid-beta (Aβ1-42), total tau (t-tau), phosphorylated tau (p-tau) and Aβ1-42/p-tau ratio according to the Luminex method. MRI was performed in all individuals, and was scored independently by two experts according to Fazekas scale. Statistical analyses were conducted with the aid of general linear model procedures, and the Chi-squared test. Results: T-tau levels were significantly associated with subcortical lesion pattern when Fazekas was considered as a group factor. CSF biomarkers were not associated with MCI, AD, or controls when considered separately. There was a tendency for reduction in CSF Aβ1-42 together with increasing Fazekas scores, but without statistical significance. Comparisons of Aβ1-42 and t-tau with each clinical group or with each neuroimaging pattern did not reach statistical differences. Likewise, Fazekas scores had no impact on CAMCOG scores. Conclusion: We found a significant association between t-tau levels and subcortical lesions when all Fazekas classifications were considered as a single group; comparisons of Fazekas subgroups and CSF biomarkers did not reach significance.
- Long-Term, Low-Dose Lithium Treatment Does Not Impair Renal Function in the Elderly: A 2-Year Randomized, Placebo-Controlled Trial Followed by Single-Blind Extension(2014) APRAHAMIAN, Ivan; SANTOS, Franklin S.; SANTOS, Bernardo dos; TALIB, Leda; DINIZ, Breno S.; RADANOVIC, Marcia; GATTAZ, Wagner F.; FORLENZA, Orestes V.Background: Recent studies evaluated the disease-modifying properties of lithium in mild cognitive impairment and dementia. Although potentially effective for these purposes, chronic lithium use in regard to safety in the elderly needs to be better explored. Objective: To evaluate the effect of long-term lithium treatment at subtherapeutic doses on renal function in older adults. Secondary aims were to evaluate the clinical safety and tolerability of this treatment and its effects on thyroid, immune, and glycemic functions. Method: Between February 2007 and October 2011, a 2-year randomized, double-blind, placebo-controlled trial followed by a single-blinded phase for an additional 2 years. Sixty-one patients with mild cognitive impairment (Mayo Clinic criteria) were randomized to receive lithium or placebo. Renal function was estimated by the abbreviated Modification of Diet in Renal Disease (aMDRD) and the Chronic Kidney Disease-Epidemiology study (CKD-EPI) equations. Leukocytes, serum thyroid-stimulating hormone (TSH) and free thyroxine (T-4), and serum glucose and insulin were determined. Tolerability was evaluated at 3-month intervals through systematic clinical examinations and by the UKU Side Effect Rating Scale. Results: Analysis of longitudinal regression indicated that no significant changes in renal function were detected by the aMDRD (P = .453) and CKD-EPI (P = .213) equations after 4 years of lithium treatment. Significant increases in the number of neutrophils (P = .038), serum TSH (P = .034), and body weight (P = .015) were observed in the lithium group. The lithium group presented more overall adverse events (P = .045), particularly interfering in daily activities (P < .001). In addition, those patients had a higher incidence of diabetes mellitus (P = .037) and arrhythmia (P = .028). Conclusions: Chronic use of lithium at low doses did not affect renal function and was clinically safe. However, some other potentially relevant adverse events were observed and others could not be ruled out due to limitations of the study design. (C) Copyright 2014 Physicians Postgraduate Press, Inc.
- Cognitive impairment in remitted late -life depression is not associated with Alzheimer's disease -related CSF biomarkers(2020) LOUREIRO, Julia C.; STELLA, Florindo; PAIS, Marcos V.; RADANOVIC, Marcia; CANINEU, Paulo R.; JOAQUIM, Helena P. G.; TALIB, Leda L.; FORLENZA, Orestes V.