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[Background] The risk of developing Alzheimer's disease (AD) is modulated by genetic and environmental factors. Early-life stress (ELS) exposure during critical periods of brain development can impact later brain function and health, including increasing the risk of developing AD. Microglial dysfunction and neuroinflammation have been implicated as playing a role in AD pathology and may be modulated by ELS. To complicate matters further, sex-specific effects have been noted in response to ELS and in the incidence and progression of AD., [Methods] Here, we subjected male and female mice with either a wild type or 5xFAD familial AD-model background to maternal separation (MS) from postnatal day 2 to 14 to induce ELS., [Results] We detected hippocampal neuroinflammatory alterations already at postnatal day 15. By 4 months of age, MS mice presented increased immobility time in the forced swim test and a lower discrimination index in the novel object recognition memory test compared to controls. We found altered Bdnf and Arc expression in the hippocampus and increased microglial activation in the prefrontal cortex due to MS in a sex-dependent manner. In 5xFAD mice specifically, MS exacerbated amyloid-beta deposition, particularly in females. In the periphery, the immune cell population was altered by MS exposure., [Conclusion] Overall, our results demonstrate that MS has both short- and long-term effects on brain regions related to memory and on the inflammatory system, both in the brain and periphery. These ELS-related effects that are detectable even in adulthood may exacerbate pathology and increase the risk of developing AD via sex-specific mechanisms., Open access funding provided by Lund University. This study was funded by the Olle Engkvist Foundation, the Swedish Medical Research Council, the Swedish Alzheimer Foundation, the Swedish Brain Foundation, the Crafoord Foundation, the Swedish Dementia Association, the G&J Kock Foundation, the Royal Physiographic Society, the Fredrik O Ingrid Thurings Stiftelse, the A.E. Berger Foundation, the Swedish Parkinson Foundation and the Strategic Research Area MultiPark at Lund University.

In molecular neurobiology, perhaps no molecule has been as thoroughly examined as Alzheimer's beta-amyloid precursor protein (beta-APP). In the years since the cDNA encoding beta-APP was cloned, the protein has been the subject of unparalleled scrutiny on all levels. From molecular genetics and cellular biology to neuroanatomy and epidemiology, no scientific discipline has been left unexplored - and with good reason. beta-amyloid (Abeta) is the main constituent of the amyloidogenic plaques which are a primary pathological hallmark of Alzheimer's disease, and bta-APP is the protein from which Abeta is cleaved and released. Unraveling the molecular events underlying Abeta generation has been, and remains, of paramount importance to scientists in our field. In this review we will trace the progress that has been made in understanding the molecular and cellular basis of beta-APP trafficking and processing, or alternatively stated, the molecular basis for Abeta generation. Imperative to a complete understanding of Abeta generation is the delineation of its subcellular localization and the identification of proteins that play either direct or accessory roles in Abeta generation. We will focus on the regulation of beta-APP cleavage through diverse signal transduction mechanisms and discuss possible points of therapeutic intercession in what has been postulated to be a seminal molecular step in the cascade of events terminating in the onset of dementia, loss of neurons, and eventual death from Alzheimer's disease.

Inheritance of the apolipoprotein E (ApoE) epsilon 4 allele is a risk factor for Alzheimer's disease (AD) and is associated with increased deposition of beta-amyloid (A beta) in AD, Down's syndrome, and normal aging. A beta deposition in the form of senile plaques (SPs) has recently been described in patients with temporal lobe epilepsy (TLE). We studied the relationship between ApoE epsilon 4 genotype and the deposition of A beta in temporal lobe tissue from patients who underwent temporal lobectomy for intractable epilepsy. TLE patients with SPs had a 70% ApoE epsilon 4 carrier frequency compared with a 27% carrier frequency among age-matched TLE controls without SPs. Our data suggest that the association between ApoE epsilon 4 and intracerebral A beta accumulation is not unique to the elderly or to those with dementia, and may be a feature of conditions in which there is both an ApoE epsilon 4 allele and over-production of A beta precursor protein, and, presumably, A beta.

Colchicine may induce a myoneuropathy in patients with renal insufficiency. To date, myotonia has not been described in this disorder. We recently studied 4 patients treated with routine doses of colchicine who, in the setting of renal insufficiency, developed a severe myoneuropathy characterized by prominent myotonic discharges on electromyography. In addition, 1 of the 4 patients had profound clinical myotonia. In the 3 patients in whom biopsies were performed, marked myopathic change with intracytoplasmic vacuolization was identified. All 4 patients improved rapidly with discontinuation of the medication. The patient in whom electrophysiologic studies were repeated had a complete resolution of the myotonic discharges. Colchicine myoneuropathy can present with prominent clinical and electrophysiologic myotonia that resolves completely with discontinuation of the medication.