Publications by authors named "McDonnell D"

Background: In a recently published 24-week maintenance study of olanzapine long-acting injection (LAI) in schizophrenia (Kane et al., 2010), apparent dose-associated changes were noted in both efficacy and safety parameters. To help clinicians balance safety and efficacy when choosing a dose of olanzapine LAI, we further studied these changes.

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Retinal pigment epithelial (RPE) cells play a vital role in retinal physiology by forming the outer blood-retina barrier and supporting photoreceptor function. Retinopathies including age-related macular degeneration (AMD) involve physiological and pathological changes in the epithelium, severely impairing the retina and effecting vision. Nuclear receptors (NRs), including peroxisome proliferator-activated receptor and liver X receptor, have been identified as key regulators of physiological pathways such as lipid metabolic dysregulation and inflammation, pathways that may also be involved in development of AMD.

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The mineralocorticoid receptor (MR) is a member of the nuclear receptor superfamily. Pathological activation of the MR causes cardiac fibrosis and heart failure, but clinical use of MR antagonists is limited by the renal side effect of hyperkalemia. The glucocorticoid cortisol binds the MR with equivalent affinity to that of the mineralocorticoids aldosterone and deoxycorticosterone.

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While patients with advanced prostate cancer initially respond favorably to androgen ablation therapy, most experience a relapse of the disease within 1-2 years. Although hormone-refractory disease is unresponsive to androgen-deprivation, androgen receptor (AR)-regulated signaling pathways remain active and are necessary for cancer progression. Thus, both AR itself and the processes downstream of the receptor remain viable targets for therapeutic intervention.

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Both pro- and antimitogenic activities have been ascribed to progesterone receptor (PR) agonists and antagonists in breast cancer cells; however, the transcriptional responses that underlie these paradoxical functions are not apparent. Using nontransformed, normal human mammary epithelial cells engineered to express PR and standard microarray technology, we defined 2370 genes that were significantly regulated by the PR agonist R5020. Gene ontology (GO) analysis revealed that GO terms involved in inflammation and nuclear factor-κB (NF-κB) signaling were among the most significantly regulated.

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Oral-to-depot dose correspondence was explored in a 24-week study of olanzapine long-acting injection (LAI). Patients with schizophrenia stabilized on oral olanzapine of 10, 15, or 20 mg/day (n=1065) were randomized to continue their oral treatment or switch directly to a fixed dose of olanzapine LAI [(mg/weeks) 45/4, 150/2, 405/4, or 300/2] without oral supplementation. Six-month relapse rates for each LAI-dose group stratified by earlier oral dose were analyzed using a Cox proportional hazard model assessing risk of relapse relative to each oral dose.

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Our understanding of the molecular mechanisms underlying the pharmacological actions of estrogen receptor (ER) ligands has evolved considerably in recent years. Much of this knowledge has come from a detailed dissection of the mechanism(s) of action of the Selective Estrogen Receptor Modulators (SERMs) tamoxifen and raloxifene, so called for their ability to function as ER agonists or antagonists depending on the tissue in which they operate. These mechanistic insights have had a significant impact on the discovery of second generation SERMs, some of which are in late stage clinical development for the treatment/prevention of breast cancer as well as other estrogenopathies.

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Elevated expression of the orphan nuclear receptor estrogen-related receptor α (ERRα) has been associated with a negative outcome in several cancers, although the mechanism(s) by which this receptor influences the pathophysiology of this disease and how its activity is regulated remain unknown. Using a chemical biology approach, it was determined that compounds, previously shown to inhibit canonical Wnt signaling, also inhibited the transcriptional activity of ERRα. The significance of this association was revealed in a series of biochemical and genetic experiments that show that (a) ERRα, β-catenin (β-cat), and lymphoid enhancer-binding factor-1 form macromolecular complexes in cells, (b) ERRα transcriptional activity is enhanced by β-cat expression and vice versa, and (c) there is a high level of overlap among genes previously shown to be regulated by ERRα or β-cat.

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Polyglutamine expansion within the androgen receptor (AR) causes spinal and bulbar muscular atrophy (SBMA) and is associated with misfolded and aggregated species of the mutant AR. We showed previously that nuclear localization of the mutant AR was necessary but not sufficient for SBMA. Here we show that an interdomain interaction of the AR that is central to its function within the nucleus is required for AR aggregation and toxicity.

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Objective: Adding another antipsychotic to a treatment regimen was previously used in evaluating the medication's efficacy. Supplementation of depot antipsychotics with oral antipsychotics is particularly meaningful because depot formulations are typically chosen for patients struggling with adherence to oral antipsychotics. This post-hoc analysis assessed supplementation of olanzapine long-acting injection (olanzapine-LAI) with oral olanzapine.

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Background: Olanzapine long-acting injection (LAI) is a salt-based depot antipsychotic combining olanzapine and pamoic acid. The slow intramuscular dissolution of this practically insoluble salt produces an extended release of olanzapine lasting up to 4 weeks. However, in a small number of injections (< 0.

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Background: An advance in the treatment of schizophrenia is the development of long-acting intramuscular formulations of antipsychotics, such as olanzapine long-acting injection (LAI). During clinical trials, a post-injection syndrome characterized by signs of delirium and/or excessive sedation was identified in a small percentage of patients following injection with olanzapine LAI.

Methods: Safety data from all completed and ongoing trials of olanzapine LAI were reviewed for possible cases of this post-injection syndrome.

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Osteoporosis is an important clinical problem, affecting more than 50% of people over age 50 yr. Estrogen signaling is critical for maintaining proper bone density, and the identification of an endogenous selective estrogen receptor (ER) modulator, 27-hydroxycholesterol (27HC), suggests a mechanism by which nutritional/metabolic status can influence bone biology. With its levels directly correlated with cholesterol, a new possibility emerges wherein 27HC links estrogen and cholesterol signaling to bone homeostasis.

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An analysis of mRNA expression in T47D breast cancer cells treated with the synthetic progestin R5020 revealed a subset of progesterone receptor (PR) target genes that are enriched for E2F binding sites. Following up on this observation, we determined that PR-B acts in both direct and indirect manners to positively upregulate E2F1 expression in T47D cells. The direct effects of PR on E2F1 expression were confirmed by chromatin immunoprecipitation (ChIP) analysis, which indicated that the agonist-bound receptor was recruited to several enhancer elements proximal to the E2F1 transcript.

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This cross-sectional study examined the relationships between household smoking restrictions and intentions to quit smoking among Korean American male smokers in California. We used data from the California Korean American Tobacco Use Survey (CKATUS), which was conducted in 2004 using computer-assisted telephone interviewing. Among the 2,545 respondents who participated in the CKATUS, the 387 male smokers who answered a question assessing their intention to quit smoking were included in the final analyses.

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Objectives: To compare Pap screening in the previous 3 years among subgroups of Asian American women, aged 18 to 65 years.

Design: Analysis of data from the 2001 and 2003 California Health Interview Survey (CHIS), a cross-sectional population-based telephone survey.

Main Measures: The survey elicited information from major Asian subgroups, including Chinese, Filipina, Japanese, Korean, South Asian, and Vietnamese.

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Hematopoietic stem cells (HSCs) are enriched for aldehyde dehydrogenase (ALDH) activity and ALDH is a selectable marker for human HSCs. However, the function of ALDH in HSC biology is not well understood. We sought to determine the function of ALDH in regulating HSC fate.

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The current statistics associated with breast cancer continue to show a relatively high recurrence rate together with a poor survival for aggressive metastatic disease. These findings reflect, in part, the pharmaceutical intractability of processes involved in the metastatic process and highlight the need to identify additional drug targets for the treatment of late-stage disease. In the current study, we report that ligand activation of the aryl-hydrocarbon receptor (AhR) inhibits multiple aspects of the metastatic process in a panel of breast cancer cell lines that represent the major breast cancer subtypes.

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Objective: The purpose of the present study was to evaluate the efficacy and tolerability of olanzapine long-acting injection for maintenance treatment of schizophrenia.

Method: Outpatients with schizophrenia who had maintained stability on an oral regimen of olanzapine (10, 15, or 20 mg/day) for 4 to 8 weeks were randomly assigned to 24 weeks of double-blind treatment with "low" (150 mg every 2 weeks; N=140), "medium" (405 mg every 4 weeks; N=318), or "high" (300 mg every 2 weeks; N=141) doses of olanzapine long-acting injection; a very low reference dose of olanzapine long-acting injection (45 mg every 4 weeks; N=144); or their stabilized dose of oral olanzapine (N=322). Rates of and time to psychotic exacerbation were estimated using Kaplan-Meier methodology.

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The androgen receptor (AR) is a DNA-binding and hormone-activated transcription factor that plays critical roles in the development and progression of prostate cancer. The transcriptional function of AR is modulated by intermolecular interactions with DNA elements and coactivator proteins, as well as intramolecular interactions between AR domains; thus, the structural information from the full-length AR or a multi-domain fragment is essential for understanding the molecular basis of AR functions. Here we report the expression and purification of full-length AR protein and of a fragment containing its DNA-binding and ligand-binding domains connected by the hinge region in the presence of its natural ligand, dihydrotestosterone.

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Energy production by oxidative metabolism in kidney, stomach, and heart, is primarily expended in establishing ion gradients to drive renal electrolyte homeostasis, gastric acid secretion, and cardiac muscle contraction, respectively. In addition to orchestrating transcriptional control of oxidative metabolism, the orphan nuclear receptor, estrogen-related receptor gamma (ERRgamma), coordinates expression of genes central to ion homeostasis in oxidative tissues. Renal, gastric, and cardiac tissues subjected to genomic analysis of expression in perinatal ERRgamma null mice revealed a characteristic dysregulation of genes involved in transport processes, exemplified by the voltage-gated potassium channel, Kcne2.

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Nuclear receptors (NRs) regulate a panoply of biological processes, including the function and development of cells within the hematopoietic and immune system, such as erythrocytes, monocytes, and lymphocytes. Significantly less is known regarding the function of NRs in regulating the fate of hematopoietic stem cells (HSCs), the self-renewing, pluripotent cells that give rise to the entirety of the blood and immune systems throughout the lifetime of an individual. Several recent studies suggest, either directly or indirectly, a role for members of the NR family in regulating the differentiation and self-renewal of HSCs, embryonic stem cells, and induced pluripotent stem cells.

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HOXB13 is a member of the homeodomain family of sequence-specific transcription factors and, together with the androgen receptor (AR), plays a critical role in the normal development of the prostate gland. We demonstrate here that, in prostate cancer cells, HOXB13 is a key determinant of the response to androgens. Specifically, it was determined that HOXB13 interacts with the DNA-binding domain of AR and inhibits the transcription of genes that contain an androgen-response element (ARE).

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Selective estrogen receptor modulators (SERMs), such as tamoxifen (TAM), have been used extensively for the treatment and prevention of breast cancer and other pathologies associated with aberrant estrogen receptor (ER) signaling. These compounds exhibit cell-selective agonist/antagonist activities as a consequence of their ability to induce different conformational changes in ER, thereby enabling it to recruit functionally distinct transcriptional coregulators. However, the observation that SERMs can also regulate aspects of calcium signaling and apoptosis in an ER-independent manner in some systems suggests that some of the activity of drugs within this class may also arise as a consequence of their ability to interact with targets other than ER.

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