2A4 binds soluble and insoluble light chain aggregates from AL amyloidosis patients and promotes clearance of amyloid deposits by phagocytosis .

Amyloid light chain (AL) amyloidosis is characterized by misfolded light chain (LC) (amyloid) deposition in various peripheral organs, leading to progressive dysfunction and death. There are no regulatory agency-approved treatments for AL amyloidosis, and none of the available standard of care approaches directly targets the LC protein that constitutes the amyloid. NEOD001, currently in late-stage clinical trials, is a conformation-specific, anti-LC antibody designed to specifically target misfolded LC aggregates and promote phagocytic clearance of AL amyloid deposits.

The prodrug DHED selectively delivers 17β-estradiol to the brain for treating estrogen-responsive disorders.

Many neurological and psychiatric maladies originate from the deprivation of the human brain from estrogens. However, current hormone therapies cannot be used safely to treat these conditions commonly associated with menopause because of detrimental side effects in the periphery. The latter also prevents the use of the hormone for neuroprotection.

A sensitive aβ oligomer assay discriminates Alzheimer's and aged control cerebrospinal fluid.

A hallmark of Alzheimer's disease (AD) brain is the amyloid β (Aβ) plaque, which is comprised of Aβ peptides. Multiple lines of evidence suggest that Aβ oligomers are more toxic than other peptide forms. We sought to develop a robust assay to quantify oligomers from CSF.

Urinary biomarkers trefoil factor 3 and albumin enable early detection of kidney tubular injury.

The capacities of urinary trefoil factor 3 (TFF3) and urinary albumin to detect acute renal tubular injury have never been evaluated with sufficient statistical rigor to permit their use in regulated drug development instead of the current preclinical biomarkers serum creatinine (SCr) and blood urea nitrogen (BUN). Working with rats, we found that urinary TFF3 protein levels were markedly reduced, and urinary albumin were markedly increased in response to renal tubular injury. Urinary TFF3 levels did not respond to nonrenal toxicants, and urinary albumin faithfully reflected alterations in renal function.

Inhibition of calcineurin-mediated endocytosis and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors prevents amyloid beta oligomer-induced synaptic disruption.

Synaptic degeneration, including impairment of synaptic plasticity and loss of synapses, is an important feature of Alzheimer disease pathogenesis. Increasing evidence suggests that these degenerative synaptic changes are associated with an accumulation of soluble oligomeric assemblies of amyloid beta (Abeta) known as ADDLs. In primary hippocampal cultures ADDLs bind to a subpopulation of neurons.

Oligomers of beta-amyloid are sequestered into and seed new plaques in the brains of an AD mouse model.

Amyloid plaque deposition in the brain is a hallmark of Alzheimer's disease, but recent evidence indicates that the disease may be primarily caused by soluble amyloid-beta (1-42) (Abeta) oligomers or Abeta-derived diffusible ligands (ADDLs). ADDLs induce cognitive deficits in animal models and are thought to assemble in vitro by a mechanism apart from plaque formation. To investigate the in vivo relationship of ADDLs and plaques, biotin-labeled ADDLs (bADDLs) or amylin oligomers (bAMs) were injected into the hippocampus of hAPP overexpressing mice.

Selective activation of the M1 muscarinic acetylcholine receptor achieved by allosteric potentiation.

The forebrain cholinergic system promotes higher brain function in part by signaling through the M(1) muscarinic acetylcholine receptor (mAChR). During Alzheimer's disease (AD), these cholinergic neurons degenerate, therefore selectively activating M(1) receptors could improve cognitive function in these patients while avoiding unwanted peripheral responses associated with non-selective muscarinic agonists. We describe here benzyl quinolone carboxylic acid (BQCA), a highly selective allosteric potentiator of the M(1) mAChR.

Anti-ADDL antibodies differentially block oligomer binding to hippocampal neurons.

Abeta-derived diffusible ligands (ADDLs) are abundant in AD brain, bind to hippocampal neurons and induce deficits in rodent cognition. To further investigate ADDL binding to neurons and identify antibodies that block this association, a panel of anti-Abeta and anti-ADDL antibodies was characterized for their ability to immuno-detect neuronally bound ADDLs and attenuate the binding of ADDLs to neurons. The results showed that anti-Abeta and anti-ADDL antibodies were able to abate ADDLs binding to hippocampal neurons, but to different degrees.

Alzheimer's disease-type neuronal tau hyperphosphorylation induced by A beta oligomers.

Alzheimer's disease (AD) is characterized by presence of extracellular fibrillar A beta in amyloid plaques, intraneuronal neurofibrillary tangles consisting of aggregated hyperphosphorylated tau and elevated brain levels of soluble A beta oligomers (ADDLs). A major question is how these disparate facets of AD pathology are mechanistically related. Here we show that, independent of the presence of fibrils, ADDLs stimulate tau phosphorylation in mature cultures of hippocampal neurons and in neuroblastoma cells at epitopes characteristically hyperphosphorylated in AD.

Solution state characterization of amyloid beta-derived diffusible ligands.

A growing body of evidence suggests that soluble oligomeric forms of the amyloid beta peptide known as amyloid-derived diffusible ligands (ADDLs) are the toxic species responsible for neurodegeneration associated with Alzheimer's disease. Accurate biophysical characterization of ADDL preparations is hampered by the peptide's strong tendency to self-associate and the effect of factors such as ionic strength, temperature, and pH on its behavior. In addition, amyloid peptides are known to interact with common laboratory excipients, specifically detergents, further complicating the results from standard analytical methods such as denaturing polyacrylamide gel electrophoresis.

LRRTM3 promotes processing of amyloid-precursor protein by BACE1 and is a positional candidate gene for late-onset Alzheimer's disease.

Rare familial forms of Alzheimer's disease (AD) are thought to be caused by elevated proteolytic production of the Abeta42 peptide from the beta-amyloid-precursor protein (APP). Although the pathogenesis of the more common late-onset AD (LOAD) is not understood, BACE1, the protease that cleaves APP to generate the N terminus of Abeta42, is more active in patients with LOAD, suggesting that increased amyloid production processing might also contribute to the sporadic disease. Using high-throughput siRNA screening technology, we assessed 15,200 genes for their role in Abeta42 secretion and identified leucine-rich repeat transmembrane 3 (LRRTM3) as a neuronal gene that promotes APP processing by BACE1.

Amphetamine-induced locomotor activity is reduced in mice following MPTP treatment but not following selegiline/MPTP treatment.

MPTP treatment has been used in mice to cause dopaminergic neuronal cell loss and subsequent behavioral abnormalities. As such, this animal model is often used as a method for the characterization of putative novel therapeutics for disease states characterized by dopamine loss, such as Parkinson's disease. Previous reports of behavioral abnormalities in mice following MPTP intoxication, however, have been conflicting.

Differential modulation of estrogen receptors (ERs) in ischemic brain injury: a role for ERalpha in estradiol-mediated protection against delayed cell death.

Estradiol enhances plasticity and survival of the injured brain. Our previous work demonstrates that physiological levels of estradiol protect against cerebral ischemia in the young and aging brain through actions involving estrogen receptors (ERs) and alterations in gene expression. The major goal of this study was to establish mechanisms of neuroprotective actions induced by low levels of estradiol.

Estrogen attenuates the MPTP-induced loss of dopamine neurons from the mouse SNc despite a lack of estrogen receptors (ERalpha and ERbeta).

Estrogen attenuates the loss of dopamine from striatum and dopamine neurons from the substantia nigra (SNc) in animal models of Parkinson's disease. Interestingly, estrogen receptors (ERalpha and ERbeta) are thought to be sparse or absent in mouse striatum and SNc. Since ERalpha is markedly induced in rodent cortex after ischemic injury, the present studies evaluated changes in ERs after acute treatment with the dopamine neurotoxin MPTP.

Neuroprotection by estrogen in animal models of global and focal ischemia.

Estrogen has been demonstrated to protect against brain injury, neurodegeneration, and cognitive decline. Furthermore, estrogen seems to specifically protect cortical and hippocampal neurons from ischemic injury. Here our data evaluating the neuroprotective effects of estrogens, the selective estrogen receptor modulators (SERMs), and estrogen receptor alpha- and beta-selective ligands in animal models of ischemic injury are discussed.

Expression of Disrupted-In-Schizophrenia-1, a schizophrenia-associated gene, is prominent in the mouse hippocampus throughout brain development.

DISC1 (Disrupted-In-Schizophrenia 1) has been associated with schizophrenia in multiple genetic studies. Studies from our laboratory have shown that Disc1, the mouse ortholog of DISC1, is highly expressed in the dentate gyrus of the hippocampus in the adult mouse brain. Because developmental dysfunction of the hippocampus is thought to play a major role in schizophrenia pathogenesis, and the dentate gyrus is a major locus for adult neurogenesis in the mouse, we investigated Disc1 expression during mouse brain development.

Localization of B1 bradykinin receptor mRNA in the primate brain and spinal cord: an in situ hybridization study.

The bradykinin 1 and 2 receptors (B1R, B2R) are important mediators of cardiovascular homeostasis, inflammation, and nociception. While B2R is constitutively expressed in many tissues, B1R expression is thought to be absent, but induced under proinflammatory conditions. However, recent data from knockout mice have indicated that B1R acts centrally to mediate nociception, a finding that suggests the constitutive presence of B1R in brain and/or spinal cord.

DISC1 (Disrupted in Schizophrenia-1) is expressed in limbic regions of the primate brain.

Disrupted in Schizophrenia-1 (DISC1) was identified as truncated by a balanced translocation segregating with schizophrenia and other major mental illness in a large Scottish family. As a step in evaluating the function of DISC1 and its potential role in human schizophrenia, we have determined its regional expression in the primate brain by in situ hybridization. DISC1 expression is highly localized, with most prominent expression in the dentate gyrus of the hippocampus and lateral septum, and lower levels of expression in the cerebral cortex, amygdala, paraventricular hypothalamus, cerebellum, interpeduncular nucleus, and subthalamic nucleus.

Sex-related differences in the distribution of opioid receptor-like 1 receptor mRNA and colocalization with estrogen receptor mRNA in neurons of the spinal trigeminal nucleus caudalis in the rat.

We recently reported that exogenously applied orphanin FQ, the endogenous ligand for opioid receptor-like 1 (ORL(1)) receptor, produces sex-specific modulation of trigeminal nociception, and that estrogen contributes to these sex-related differences. Estrogen could produce these sex-related differences by altering the expression of the ORL(1)-receptor gene in the trigeminal nucleus caudalis. Utilizing in situ hybridization, we compared levels of ORL(1) receptor mRNA and investigated its colocalization with estrogen receptor mRNA in trigeminal neurons.

Estrogen prevents the loss of CA1 hippocampal neurons in gerbils after ischemic injury.

Estrogen replacement therapy is thought to attenuate the incidence of Alzheimer's disease in women and enhance cognitive functions. In rodents, estrogen protects cerebral cortical neurons from ischemic injury and cultured neurons from a variety of perturbations. Because few nuclear estrogen receptors have been detected in the dorsal hippocampus, the present studies used a global ischemia model to evaluate the neuroprotective actions of estrogen in this region.

Cloning and characterization of Disc1, the mouse ortholog of DISC1 (Disrupted-in-Schizophrenia 1).

We cloned the mouse ortholog of DISC1 (Disrupted-in-Schizophrenia 1), a candidate gene for schizophrenia. Disc1 is 3163 nucleotides long and has 60% identity with the human DISC1. Disc1 encodes 851 amino acids and has 56% identity with the human protein.

Estrogen modulates oxytocin gene expression in regions of the rat supraoptic and paraventricular nuclei that contain estrogen receptor-beta.

Oxytocin is an important modulator of female reproductive functions including parturition, lactation and maternal behavior, while vasopressin regulates water balance and acts as a neurotransmitter. For decades, it has been suggested that estrogen regulates the production and/or release of oxytocin and vasopressin in the rodent brain. Although several studies demonstrated that estrogen can modulate vasopressin mRNA levels in regions known to contain estrogen receptor (ER), such as the bed nucleus of the stria terminalis and medial amygdala, data from the paraventricular and supraoptic nuclei were inconclusive.

Methods to enhance signal using isotopic in situ hybridization.

Isotopic in situ hybridization (ISH) has been established as a uniquely powerful tool for the study of gene expression in specific cell types. This technique allows the visualization and quantification of gene expression and gene expression changes in cells. In our study of biological and molecular phenomena, we have increasingly encountered the need to detect small changes in gene expression as well as genes of low abundance, such as the oxytocin receptor (OTR) and the tuberoinfundibular peptide of 39 residues (Tip39).

Estrogen-binding sites and their functional capacity in estrogen receptor double knockout mouse brain.

Early studies found estrogen-binding sites in the ER knockout (ERalphaKO) mouse brain, suggesting a splice variant of ERalpha or another ER. The discovery of ERbeta suggested that binding was due to ERbeta, although questions about an ERgamma remained. To test this hypothesis, ERbetaKO mice were generated and crossed with ERalphaKO mice, and ERalpha/betaKO animals were used for in vivo binding studies with [(125)I]estrogen.

Age differentially influences estrogen receptor-alpha (ERalpha) and estrogen receptor-beta (ERbeta) gene expression in specific regions of the rat brain.

Estradiol's ability to influence neurochemical events that are critical to female reproductive cyclicity and behavior decreases with age. We tested the hypothesis that decreases in estrogen receptor-alpha (ERalpha) and/or ERbeta mRNA explain the brain's declining responsiveness to estradiol. We assessed ERalpha and ERbeta mRNA levels in intact and ovariectomized estradiol-treated rats.