Caselli, Richard J.

✓The aim of this study is to evaluate the presentation of unusual dementias in 4 patients and correlate these presentations with the histopathological findings after brain biopsy sampling to define a diagnostic entity. The authors detail the cases of 4 patients (2 women, 46 and 56 years of age; and 2 men, 67 and 74 years of age) who presented with acute and subsequently subacute encephalopathies. Their bizarre presenting symptom complexes and the results of neurological examinations, radiographic studies, electroencephalography (EEG) recordings, and serological marker tests are reviewed. The diagnostic surgical procedures and successful treatments in these patients are discussed. All 4 patients underwent craniotomy and excisional brain biopsy sampling as part of a comprehensive evaluation. Histopathological confirmation of nonvasculitic autoimmune inflammatory meningoencephalitis (NAIM) by a neuropathologist was present in all 4 patients. All patients were successfully treated with a course of corticosteroid medication. Nonvasculitic autoimmune inflammatory meningoencephalitis is a potentially treatable form of dementia whose salient features include a younger average age at onset, rapid progression with significant cognitive and behavioral features, absence of family history, abnormal EEG findings, and elevated levels of inflammatory markers. Although it is an invasive procedure, brain biopsy sampling is safe and can offer histological confirmation of this condition. This procedure is important because NAIM can be treated successfully if it is distinguished from the nontreatable dementias that mimic it.

Alzheimer's disease (AD) is associated with regional reductions in fluorodeoxyglucose positron emission tomography (FDG PET) measurements of the cerebral metabolic rate for glucose, which may begin long before the onset of histopathological or clinical features, especially in carriers of a common AD susceptibility gene. Molecular evaluation of cells from metabolically affected brain regions could provide new information about the pathogenesis of AD and new targets at which to aim disease-slowing and prevention therapies. Data from a genome-wide transcriptomic study were used to compare the expression of 80 metabolically relevant nuclear genes from laser-capture microdissected non-tangle-bearing neurons from autopsy brains of AD cases and normal controls in posterior cingulate cortex, which is metabolically affected in the earliest stages; other brain regions metabolically affected in PET studies of AD or normal aging; and visual cortex, which is relatively spared. Compared with controls, AD cases had significantly lower expression of 70% of the nuclear genes encoding subunits of the mitochondrial electron transport chain in posterior cingulate cortex, 65% of those in the middle temporal gyrus, 61% of those in hippocampal CA1, 23% of those in entorhinal cortex, 16% of those in visual cortex, and 5% of those in the superior frontal gyrus. Western blots confirmed underexpression of those complex I–V subunits assessed at the protein level. Cerebral metabolic rate for glucose abnormalities in FDG PET studies of AD may be associated with reduced neuronal expression of nuclear genes encoding subunits of the mitochondrial electron transport chain.

Alzheimer's Disease (AD) is the most widespread form of dementia during the later stages of life. If improved therapeutics are not developed, the prevalence of AD will drastically increase in the coming years as the world's population ages. By identifying differences in neuronal gene expression profiles between healthy elderly persons and individuals diagnosed with AD, we may be able to better understand the molecular mechanisms that drive AD pathogenesis, including the formation of amyloid plaques and neurofibrillary tangles. In this study, we expression profiled histopathologically normal cortical neurons collected with laser capture microdissection (LCM) from six anatomically and functionally discrete postmortem brain regions in 34 AD-afflicted individuals, using Affymetrix Human Genome U133 Plus 2.0 microarrays. These regions include the entorhinal cortex, hippocampus, middle temporal gyrus, posterior cingulate cortex, superior frontal gyrus, and primary visual cortex. This study is predicated on previous parallel research on the postmortem brains of the same six regions in 14 healthy elderly individuals, for which LCM neurons were similarly processed for expression analysis. We identified significant regional differential expression in AD brains compared with control brains including expression changes of genes previously implicated in AD pathogenesis, particularly with regard to tangle and plaque formation. Pinpointing the expression of factors that may play a role in AD pathogenesis provides a foundation for future identification of new targets for improved AD therapeutics. We provide this carefully phenotyped, laser capture microdissected intraindividual brain region expression data set to the community as a public resource.

There are no Food and Drug Administration (FDA)-approved medications for the medical management of frontotemporal dementia and its related disorders, so all management recommendations are necessarily off-label and borrowed from experience with Alzheimer's disease, psychiatric disease, and related medical illnesses. Six areas of pharmacotherapeutic consideration are prevention (primary and secondary), intellectual decline, behavioral disorders (such as depression, anxiety, and psychosis), sleep disorders, frequently associated disorders (including motor neuron disease), and abrupt decline. In addition to pharmacotherapy, important lifestyle issues confronting the clinician include driving cessation, securing any weapons maintained at home, assisted living, and caregiver burnout.

In this article, we have characterized and compared gene expression profiles from laser capture microdissected neurons in six functionally and anatomically distinct regions from clinically and histopathologically normal aged human brains. These regions, which are also known to be differentially vulnerable to the histopathological and metabolic features of Alzheimer’s disease (AD), include the entorhinal cortex and hippocampus (limbic and paralimbic areas vulnerable to early neurofibrillary tangle pathology in AD), posterior cingulate cortex (a paralimbic area vulnerable to early metabolic abnormalities in AD), temporal and prefrontal cortex (unimodal and heteromodal sensory association areas vulnerable to early neuritic plaque pathology in AD), and primary visual cortex (a primary sensory area relatively spared in early AD). These neuronal profiles will provide valuable reference information for future studies of the brain, in normal aging, AD and other neurological and psychiatric disorders.

Human memory is a polygenic trait. We performed a genome-wide screen to identify memory-related gene variants. A genomic locus encoding the brain protein KIBRA was significantly associated with memory performance in three independent, cognitively normal cohorts from Switzerland and the United States. Gene expression studies showed that KIBRA was expressed in memory-related brain structures. Functional magnetic resonance imaging detected KIBRA allele–dependent differences in hippocampal activations during memory retrieval. Evidence from these experiments suggests a role for KIBRA in human memory.