Publications by authors named "Karen Newell-Rogers"

Background: Disturbances of the sleep-wake cycle and other circadian rhythms typically precede the age-related deficits in learning and memory, suggesting that these alterations in circadian timekeeping may contribute to the progressive cognitive decline during aging. The present study examined the role of immune cell activation and inflammation in the link between circadian rhythm dysregulation and cognitive impairment in aging.

Methods: C57Bl/6J mice were exposed to shifted light-dark (LD) cycles (12 h advance/5d) during early adulthood (from ≈ 4-6mo) or continuously to a "fixed" LD12:12 schedule.

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Article Synopsis
  • - The study investigates the impact of a CLIP antagonist peptide (CAP) on B cell expansion and neuroprotective effects in 5xFAD mice, which are a model for Alzheimer's disease and have a history of traumatic brain injury (TBI).
  • - Results showed that treatment with CAP significantly reduced CLIP-positive B cells and improved various impairments related to the immune system and neurobehavioral functions in the 5xFAD mice over a period of six months.
  • - However, TBI seemed to negate the effectiveness of CAP in reducing B cell populations and also exacerbated several pathological features of Alzheimer's disease, indicating a complex interaction between TBI and AD.
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  • Traumatic brain injury (TBI) leads to the expansion of B and T cells in the spleen, which is linked to increased neuroinflammation and neurodegeneration.
  • The vagus nerve controls the immune response by connecting the central nervous system to the spleen, influencing splenic immune cell behaviors.
  • Experiments showed that cutting the left vagus nerve (left vagotomy) before TBI reduced specific immune cell types, suggesting that the vagus nerve can be a target for modulating immune responses after brain injuries.
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In this report, we investigate the toxicity of the ionophore thiomaltol (Htma) and Cu salts to melanoma. Divalent metal complexes of thiomaltol display toxicity against A375 melanoma cell culture resulting in a distinct apoptotic response at submicromolar concentrations, with toxicity of Cu(tma)2 > Zn(tma)2 >> Ni(tma)2. In metal-chelated media, Htma treatment shows little toxicity, but the combination with supplemental CuCl2, termed Cu/Htma treatment, results in toxicity that increases with suprastoichiometric concentrations of CuCl2 and correlates with the accumulation of intracellular copper.

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Traumatic brain injury (TBI) precedes the onset of epilepsy in up to 15-20% of symptomatic epilepsies and up to 5% of all epilepsy. Treatment of acquired epilepsies, including post-traumatic epilepsy (PTE), presents clinical challenges, including frequent resistance to anti-epileptic therapies. Considering that over 1.

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Toll-like receptor 4 (TLR4) activation contributes to vascular dysfunction in pathological conditions such as hypertension and diabetes, but the role of chronic TLR4 activation on renal autoregulatory behavior is unknown. We hypothesized that subclinical TLR4 stimulation with low-dose lipopolysaccharide (LPS) infusion increases TLR4 activation and blunts renal autoregulatory behavior. We assessed afferent arteriolar autoregulatory behavior in male Sprague-Dawley rats after prolonged LPS (0.

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This study aimed to establish mechanistic links between the prolonged intake of desloratadine, a common H1 receptor blocker (i.e., antihistamine), and development of obesity and metabolic syndrome.

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Background/aim: Cinobufotalin (CINO), a cardiotonic steroid, has been used as an anticancer agent. This study assessed the cell-specific effect of CINO on SK-OV-3, CRL-1978 and CRL-11731 ovarian cancer cells which differ in terms of their respective karyotypes.

Materials And Methods: Cell cultures were treated with CINO (0.

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Objective: Innate immune system activation and excessive inflammation contributes to hypertension during pregnancy (HTN-preg). Activation of Toll-like receptors (TLRs), the primary innate immune system sensor, is evident in women with HTN-preg and is sufficient to induce pregnancy-dependent, proteinuric hypertension in animals. However, whether HTN-preg is a maternal disease, a placental disease, or both is unclear.

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Borrelia burgdorferi, the causative agent of Lyme disease, is a vector-borne bacterial infection that is transmitted through the bite of an infected tick. If not treated with antibiotics during the early stages of infection, disseminated infection can spread to the central nervous system (CNS). In non-human primates (NHPs) it has been demonstrated that the leptomeninges are among the tissues colonized by B.

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Cardiac myosin binding protein-C (cMyBP-C) is a heart muscle-specific thick filament protein. Elevated level of serum cMyBP-C is an indicator of early myocardial infarction (MI), but its value as a predictor of future cardiovascular disease is unknown. Based on the presence of significant amount of cMyBP-C in the serum of previous study subjects independent of MI, we hypothesized that circulating cMyBP-C is a sensitive indicator of ongoing cardiovascular stress and disease.

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Excessive innate immune system activation and inflammation during pregnancy can lead to organ injury and dysfunction and preeclampsia (PE); however, the molecular mechanisms involved are unknown. We tested the hypothesis that Toll-like receptor (TLR) activation induces major histocompatibility complex (MHC) class II invariant chain peptide (CLIP) expression on immune cells, makes them pro-inflammatory, and are necessary to cause PE-like features in mice. Treatment with VG1177, a competitive antagonist peptide for CLIP in the groove of MHC class II, was able to both prevent and treat PE-like features in mice.

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Overly fibrotic wound healing can lead to excess scar formation, causing functional impairment and undesirable cosmetic results. However, there are few successful treatments available to prevent or remediate scars. This study sought to explore the molecular mechanisms by which quercetin, a naturally-occurring antifibrotic agent, diminishes scar formation.

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This study aimed to establish mechanistic links between the aging-associated changes in the functional status of mast cells and the altered responses of mesenteric tissue and mesenteric lymphatic vessels (MLVs) to acute inflammation. We used an model of acute peritoneal inflammation induced by lipopolysaccharide treatment of adult (9-month) and aged (24-month) F-344 rats. We analyzed contractility of isolated MLVs, mast cell activation, activation of nuclear factor-κB (NF-κB) without and with stabilization of mast cells by cromolyn or blockade of all types of histamine receptors and production of 27 major pro-inflammatory cytokines in adult and aged perilymphatic mesenteric tissues and blood.

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Ineffective skin wound healing is a significant source of morbidity and mortality. Roughly 6.5 million Americans experience chronically open wounds and the cost of treating these wounds numbers in the billions of dollars annually.

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Class II invariant chain peptide (CLIP) expression has been demonstrated to play a pivotal role in the regulation of B cell function after nonspecific polyclonal expansion. Several studies have shown vitamin D3 helps regulate the immune response. We hypothesized that activated vitamin D3 suppresses CLIP expression on activated B-cells after nonspecific activation or priming of C57BL/6 mice with CpG.

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The maternal innate immune system plays an important role both in normal pregnancy as well as hypertensive disorders of pregnancy including preeclampsia (PE). We propose four pathways that involve excessive innate immunity that lead to most forms of PE. Pre-existing endothelial dysfunction plus pregnancy leads to an excessive innate immune response resulting in widespread inflammation, placental and renal dysfunction, vasoconstriction, and PE.

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Suppression of the hypothalamic-pituitary-adrenal (HPA) axis has been shown to occur during cholestatic liver injury. Furthermore, we have demonstrated that in a model of cholestasis, serum bile acids gain entry into the brain via a leaky blood brain barrier and that hypothalamic bile acid content is increased. Therefore, the aim of the current study was to determine the effects of bile acid signaling on the HPA axis.

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Hepatic encephalopathy (HE) is a serious neurological complication of acute and chronic liver failure. Expression of the neurosteroid/bile acid receptor Takeda G protein-coupled receptor 5 (TGR5) has been demonstrated in the brain and is thought to be neuroprotective. However, it is unknown how TGR5 signaling can influence the progression and associated neuroinflammation of HE.

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Background: Lymphatic dysfunction has been linked to inflammation since the 1930s. Lymphatic function in the gut and mesentery is grossly underexplored in models of inflammatory bowel disease despite the use of lymphatic occlusion in early models of inflammatory bowel disease. Activation of the innate and adaptive immune system is a hallmark of TNBS-induced inflammation and is linked to disruption of the intrinsic lymph pump.

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Lyme disease is a multisystem infection transmitted by tick vectors with an incidence of up to 300,000 individuals/yr in the United States. The primary treatments are oral or i.v.

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Article Synopsis
  • Traumatic brain injury (TBI) triggers an immune response, with the role of antigen presenting cells (APCs) in linking innate and adaptive immunity being crucial yet unclear in terms of their effects post-injury.
  • Researchers focused on how TBI causes an increase in peripheral immune cells, which could act as APCs, and explored the use of a competitive antagonist for an important peptide involved in antigen presentation, aiming to reverse neurodegeneration.
  • Findings showed that treatment with the antagonist reduced the activation of immune cells and neuroinflammation, indicating that neurodegeneration after TBI is influenced by the antigen processing that relies on a specific protein, CD74.
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Background: Excessive maternal immune system activation plays a central role in the development of the hypertensive disorder of pregnancy preeclampsia (PE). The immunomodulatory cytokines interleukin 4 (IL-4) and interleukin 10 (IL-10) are dysregulated during PE; therefore we hypothesized that treatment with both recombinant IL-4 and IL-10 during pregnancy could prevent the development of PE in mice.

Methods: Using our mouse model of PE in which immune system activation is induced by the double-stranded RNA receptor agonist poly I:C, we gave daily injections of IL-4, IL-10, or both on days 13-17 of pregnancy.

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Purpose: The aim of this study was to determine the relationship of birth weight and gestational age with regulatory T cells (Tregs) in cord blood of human newborns.

Methods: Cord blood mononuclear cells (CBMCs) of 210 newborns were analyzed using flow cytometry to identify Tregs (CD3(+), CD4(+), CD25(high), FoxP3(high)) and measure FoxP3 mean fluorescence intensity (MFI). Suppressive index (SI) was calculated as FoxP3 MFI per Treg.

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Epilepsy is a neurological seizure disorder that affects over 100 million people worldwide. Levetiracetam, either alone, as monotherapy, or as adjunctive treatment, is widely used to control certain types of seizures. Despite its increasing popularity as a relatively safe and effective anti-convulsive treatment option, its mechanism(s) of action are poorly understood.

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