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Li YH, Jiang ZX, Xu Q, Jin TT, Huang JF, Luan X, Li C, Chen XY, Wong KH, Dong XL, Sun XR. Inhibition of calcium-sensing receptor by its antagonist promotes gastrointestinal motility in a Parkinson's disease mouse model. Biomed Pharmacother 2024; 174:116518. [PMID: 38565057 DOI: 10.1016/j.biopha.2024.116518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 03/26/2024] [Accepted: 03/28/2024] [Indexed: 04/04/2024] Open
Abstract
BACKGROUND The Calcium-sensing receptor (CaSR) participates in the regulation of gastrointestinal (GI) motility under normal conditions and might be involved in the regulation of GI dysmotility in patients with Parkinson's disease (PD). METHODS CaSR antagonist-NPS-2143 was applied in in vivo and ex vivo experiments to study the effect and underlying mechanisms of CaSR inhibition on GI dysmotility in the MPTP-induced PD mouse model. FINDINGS Oral intake of NPS-2143 promoted GI motility in PD mice as shown by the increased gastric emptying rate and shortened whole gut transit time together with improved weight and water content in the feces of PD mice, and the lack of influence on normal mice. Meanwhile, the number of cholinergic neurons, the proportion of serotonergic neurons, as well as the levels of acetylcholine and serotonin increased, but the numbers of nitrergic and tyrosine hydroxylase immunoreactive neurons, and the levels of nitric oxide synthase and dopamine decreased in the myenteric plexus in the gastric antrum and colon of PD mice in response to NPS-2143 treatment. Furthermore, the numbers of c-fos positive neurons in the nucleus tractus solitarius (NTS) and cholinergic neurons in the dorsal motor nucleus of the vagus (DMV) increased in NPS-2143 treated PD mice, suggesting the involvement of both the enteric (ENS) and central (CNS) nervous systems. However, ex vivo results showed that NPS-2143 directly inhibited the contractility of antral and colonic strips in PD mice via a non-ENS mediated mechanism. Further studies revealed that NPS-2143 directly inhibited the voltage gated Ca2+ channels, which might, at least in part, explain its direct inhibitory effects on the GI muscle strips. INTERPRETATION CaSR inhibition by its antagonist ameliorated GI dysmotility in PD mice via coordinated neuronal regulation by both ENS and CNS in vivo, although the direct effects of CaSR inhibition on GI muscle strips were suppressive.
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Affiliation(s)
- Yu-Hang Li
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China
| | - Zhong-Xin Jiang
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China; Department of Clinical Laboratory, the Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Qian Xu
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China
| | - Ting-Ting Jin
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China; Department of Pathology, Women's and Children's Hospital Affiliated to Qingdao University, Qingdao, Shandong, China
| | - Jin-Fang Huang
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China; Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Xiao Luan
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China
| | - Chong Li
- Research Institute for Future Food, The Hong Kong Polytechnic University, Hong Kong, China; Department of Food Science and Nutrition, The Hong Kong Polytechnic University, Hong Kong, China
| | - Xin-Yi Chen
- Department of International Medicine, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Ka-Hing Wong
- Research Institute for Future Food, The Hong Kong Polytechnic University, Hong Kong, China; Department of Food Science and Nutrition, The Hong Kong Polytechnic University, Hong Kong, China.
| | - Xiao-Li Dong
- Research Institute for Future Food, The Hong Kong Polytechnic University, Hong Kong, China; Department of Food Science and Nutrition, The Hong Kong Polytechnic University, Hong Kong, China.
| | - Xiang-Rong Sun
- Department of Physiology and Pathophysiology, School of Basic Medicine, Qingdao University, Qingdao, Shandong, China.
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Baracaldo-Santamaría D, Avendaño-Lopez SS, Ariza-Salamanca DF, Rodriguez-Giraldo M, Calderon-Ospina CA, González-Reyes RE, Nava-Mesa MO. Role of Calcium Modulation in the Pathophysiology and Treatment of Alzheimer's Disease. Int J Mol Sci 2023; 24:ijms24109067. [PMID: 37240413 DOI: 10.3390/ijms24109067] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/02/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023] Open
Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disease and the most frequent cause of progressive dementia in senior adults. It is characterized by memory loss and cognitive impairment secondary to cholinergic dysfunction and N-methyl-D-aspartate (NMDA)-mediated neurotoxicity. Intracellular neurofibrillary tangles, extracellular plaques composed of amyloid-β (Aβ), and selective neurodegeneration are the anatomopathological hallmarks of this disease. The dysregulation of calcium may be present in all the stages of AD, and it is associated with other pathophysiological mechanisms, such as mitochondrial failure, oxidative stress, and chronic neuroinflammation. Although the cytosolic calcium alterations in AD are not completely elucidated, some calcium-permeable channels, transporters, pumps, and receptors have been shown to be involved at the neuronal and glial levels. In particular, the relationship between glutamatergic NMDA receptor (NMDAR) activity and amyloidosis has been widely documented. Other pathophysiological mechanisms involved in calcium dyshomeostasis include the activation of L-type voltage-dependent calcium channels, transient receptor potential channels, and ryanodine receptors, among many others. This review aims to update the calcium-dysregulation mechanisms in AD and discuss targets and molecules with therapeutic potential based on their modulation.
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Affiliation(s)
- Daniela Baracaldo-Santamaría
- Pharmacology Unit, Department of Biomedical Sciences, School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia
| | - Sara Sofia Avendaño-Lopez
- Pharmacology Unit, Department of Biomedical Sciences, School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia
| | - Daniel Felipe Ariza-Salamanca
- Medical and Health Sciences Education Research Group, School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia
| | - Mateo Rodriguez-Giraldo
- Grupo de Investigación en Neurociencias (NeURos), Centro de Neurociencias Neurovitae-UR, Instituto de Medicina Traslacional (IMT), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá 111221, Colombia
| | - Carlos A Calderon-Ospina
- Pharmacology Unit, Department of Biomedical Sciences, School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia
- Grupo de Investigación en Ciencias Biomédicas Aplicadas (UR Biomed), School of Medicine and Health Sciences, Universidad del Rosario, Bogotá 111221, Colombia
| | - Rodrigo E González-Reyes
- Grupo de Investigación en Neurociencias (NeURos), Centro de Neurociencias Neurovitae-UR, Instituto de Medicina Traslacional (IMT), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá 111221, Colombia
| | - Mauricio O Nava-Mesa
- Grupo de Investigación en Neurociencias (NeURos), Centro de Neurociencias Neurovitae-UR, Instituto de Medicina Traslacional (IMT), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá 111221, Colombia
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Sun W, Feng Y, Li H, He X, Lu Y, Shan Z, Teng W, Li J. The effects of maternal anti-alpha-enolase antibody expression on the brain development in offspring. Clin Exp Immunol 2022; 210:187-198. [PMID: 36149061 PMCID: PMC9750830 DOI: 10.1093/cei/uxac086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 08/25/2022] [Accepted: 09/21/2022] [Indexed: 01/25/2023] Open
Abstract
Anti-alpha-enolase autoantibodies have not only been found to play an important role in autoimmune diseases but also cause neurological damage in adults. In this study, a pregnant mouse model with high serum alpha-enolase (ENO1)-specific antibody (ENO1Ab) was established by immunization with ENO1 protein to explore the effects of maternal circulatory ENO1Ab on the brain development in offspring. The pups showed impaired learning and memory abilities with obviously thinner tight junctions in the brain tissue. IgG deposits colocalized with both ENO1 protein and complement 3 (C3), and the membrane attack complex was obviously detectable in the brain tissues of pups from dams with high serum ENO1Ab expression. Our findings suggest that highly expressed ENO1Ab in the maternal circulation can pass through the blood-placenta-barrier and the compromised blood-brain barrier into the brain tissues of offspring and may cause neurological development impairment mainly through complement-dependent cytotoxicity.
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Affiliation(s)
- Wei Sun
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
| | - Yan Feng
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
| | - Hui Li
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
| | - Xiaoqing He
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
| | - Yihan Lu
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
| | - Zhongyan Shan
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
| | - Weiping Teng
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
| | - Jing Li
- Department of Endocrinology and Metabolism, Institute of Endocrinology, NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang110001, PR China
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Iamartino L, Brandi ML. The calcium-sensing receptor in inflammation: Recent updates. Front Physiol 2022; 13:1059369. [PMID: 36467702 PMCID: PMC9716066 DOI: 10.3389/fphys.2022.1059369] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 11/07/2022] [Indexed: 07/30/2023] Open
Abstract
The Calcium-Sensing Receptor (CaSR) is a member of the class C of G-proteins coupled receptors (GPCRs), it plays a pivotal role in calcium homeostasis by directly controlling calcium excretion in the kidneys and indirectly by regulating parathyroid hormone (PTH) release from the parathyroid glands. The CaSR is found to be ubiquitously expressed in the body, playing a plethora of additional functions spanning from fluid secretion, insulin release, neuronal development, vessel tone to cell proliferation and apoptosis, to name but a few. The present review aims to elucidate and clarify the emerging regulatory effects that the CaSR plays in inflammation in several tissues, where it mostly promotes pro-inflammatory responses, with the exception of the large intestine, where contradictory roles have been recently reported. The CaSR has been found to be expressed even in immune cells, where it stimulates immune response and chemokinesis. On the other hand, CaSR expression seems to be boosted under inflammatory stimulus, in particular, by pro-inflammatory cytokines. Because of this, the CaSR has been addressed as a key factor responsible for hypocalcemia and low levels of PTH that are commonly found in critically ill patients under sepsis or after burn injury. Moreover, the CaSR has been found to be implicated in autoimmune-hypoparathyroidism, recently found also in patients treated with immune-checkpoint inhibitors. Given the tight bound between the CaSR, calcium and vitamin D metabolism, we also speculate about their roles in the pathogenesis of severe acute respiratory syndrome coronavirus-19 (SARS-COVID-19) infection and their impact on patients' prognosis. We will further explore the therapeutic potential of pharmacological targeting of the CaSR for the treatment and management of aberrant inflammatory responses.
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Affiliation(s)
- Luca Iamartino
- Department of Experimental Clinical and Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
| | - Maria Luisa Brandi
- F.I.R.M.O. (Italian Foundation for the Research on Bone Diseases), Florence, Italy
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Toledano-Díaz A, Álvarez MI, Toledano A. The relationships between neuroglial and neuronal changes in Alzheimer's disease, and the related controversies II: gliotherapies and multimodal therapy. J Cent Nerv Syst Dis 2022; 14:11795735221123896. [PMID: 36407561 PMCID: PMC9666878 DOI: 10.1177/11795735221123896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 08/05/2022] [Indexed: 08/30/2023] Open
Abstract
Since the original description of Alzheimer´s disease (AD), research into this condition has mainly focused on assessing the alterations to neurons associated with dementia, and those to the circuits in which they are involved. In most of the studies on human brains and in many models of AD, the glial cells accompanying these neurons undergo concomitant alterations that aggravate the course of neurodegeneration. As a result, these changes to neuroglial cells are now included in all the "pathogenic cascades" described in AD. Accordingly, astrogliosis and microgliosis, the main components of neuroinflammation, have been integrated into all the pathogenic theories of this disease, as discussed in this part of the two-part monograph that follows an accompanying article on gliopathogenesis and glioprotection. This initial reflection verified the implication of alterations to the neuroglia in AD, suggesting that these cells may also represent therapeutic targets to prevent neurodegeneration. In this second part of the monograph, we will analyze the possibilities of acting on glial cells to prevent or treat the neurodegeneration that is the hallmark of AD and other pathologies. Evidence of the potential of different pharmacological, non-pharmacological, cell and gene therapies (widely treated) to prevent or treat this disease is now forthcoming, in most cases as adjuncts to other therapies. A comprehensive AD multimodal therapy is proposed in which neuronal and neuroglial pharmacological treatments are jointly considered, as well as the use of new cell and gene therapies and non-pharmacological therapies that tend to slow down the progress of dementia.
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Rodríguez-Giraldo M, González-Reyes RE, Ramírez-Guerrero S, Bonilla-Trilleras CE, Guardo-Maya S, Nava-Mesa MO. Astrocytes as a Therapeutic Target in Alzheimer's Disease-Comprehensive Review and Recent Developments. Int J Mol Sci 2022; 23:13630. [PMID: 36362415 PMCID: PMC9654484 DOI: 10.3390/ijms232113630] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/25/2022] [Accepted: 10/26/2022] [Indexed: 09/20/2023] Open
Abstract
Alzheimer's disease (AD) is a frequent and disabling neurodegenerative disorder, in which astrocytes participate in several pathophysiological processes including neuroinflammation, excitotoxicity, oxidative stress and lipid metabolism (along with a critical role in apolipoprotein E function). Current evidence shows that astrocytes have both neuroprotective and neurotoxic effects depending on the disease stage and microenvironmental factors. Furthermore, astrocytes appear to be affected by the presence of amyloid-beta (Aβ), with alterations in calcium levels, gliotransmission and proinflammatory activity via RAGE-NF-κB pathway. In addition, astrocytes play an important role in the metabolism of tau and clearance of Aβ through the glymphatic system. In this review, we will discuss novel pharmacological and non-pharmacological treatments focused on astrocytes as therapeutic targets for AD. These interventions include effects on anti-inflammatory/antioxidant systems, glutamate activity, lipid metabolism, neurovascular coupling and glymphatic system, calcium dysregulation, and in the release of peptides which affects glial and neuronal function. According to the AD stage, these therapies may be of benefit in either preventing or delaying the progression of the disease.
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Affiliation(s)
| | | | | | | | | | - Mauricio O. Nava-Mesa
- Grupo de Investigación en Neurociencias (NeURos), Centro de Neurociencias Neurovitae-UR, Instituto de Medicina Traslacional (IMT), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá 111711, Colombia
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Sharma L, Sharma A, Kumar D, Asthana MK, Lalhlenmawia H, Kumar A, Bhattacharyya S, Kumar D. Promising protein biomarkers in the early diagnosis of Alzheimer's disease. Metab Brain Dis 2022; 37:1727-1744. [PMID: 35015199 DOI: 10.1007/s11011-021-00847-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 09/23/2021] [Indexed: 12/20/2022]
Abstract
Alzheimer's disease (AD) is an insidious, multifactorial disease that involves the devastation of neurons leading to cognitive impairments. Alzheimer's have compounded pathologies of diverse nature, including proteins as one important factor along with mutated genes and enzymes. Although various review articles have proposed biomarkers, still, the statistical importance of proteins is missing. Proteins associated with AD include amyloid precursor protein, glial fibrillary acidic protein, calmodulin-like skin protein, hepatocyte growth factor, matrix Metalloproteinase-2. These proteins play a crucial role in the AD hypothesis which includes the tau hypothesis, amyloid-beta (Aβ) hypothesis, cholinergic neuron damage, etc. The present review highlights the role of major proteins and their physiological functions in the early diagnosis of AD. Altered protein expression results in cognitive impairment, synaptic dysfunction, neuronal degradation, and memory loss. On the medicinal ground, efforts of making anti-amyloid, anti-tau, anti-inflammatory treatments are on the peak, having these proteins as putative targets. Few proteins, e.g., Amyloid precursor protein results in the formation of non-soluble sticky Aβ40 and Aβ42 monomers that, over time, aggregate into plaques in the cortical and limbic brain areas and neurogranin is believed to regulate calcium-mediated signaling pathways and thus modulating synaptic plasticity are few putative and potential forthcoming targets for developing effective anti-AD therapies. These proteins may help to diagnose the disease early, bode well for the successful discovery and development of therapeutic and preventative regimens for this devasting public health problem.
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Affiliation(s)
- Lalit Sharma
- Department of Pharmacology, School of Pharmaceutical Sciences, Shoolini University, Solan, 173229, India
| | - Aditi Sharma
- Department of Pharmacology, School of Pharmaceutical Sciences, Shoolini University, Solan, 173229, India
| | - Deepak Kumar
- Department of Pharmacology, School of Pharmaceutical Sciences, Shoolini University, Solan, 173229, India
| | - Manish Kumar Asthana
- Department of Humanities & Social Sciences, Indian Institute of Technology Roorkee, Roorkee, 247667, India
| | - H Lalhlenmawia
- Department of Pharmacy, Regional Institute of Paramedical and Nursing Sciences, Zemabawk, Aizawl, 796017, India
| | - Ashwani Kumar
- Council of Scientific and Industrial Research, Institute of Himalayan Bioresource Technology (CSIR-IHBT), Palampur, 176061, India
| | - Sanjib Bhattacharyya
- Department of Pharmaceutical Sciences and Chinese Traditional Medicine, Southwest University, Chongqing, 400715, People's Republic of China.
| | - Deepak Kumar
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Sciences, Shoolini University, Solan, 173 229, India.
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Abstract
Association of Epileptic and Nonepileptic Seizures and Changes in Circulating
Plasma Proteins Linked to Neuroinflammation Gledhill J, Brand E, Pollard J, Clair RS, Wallach T, Crino P.
Neurology. 2021;96(10):e1443-e1452.
doi:10.1212/WNL.0000000000011552 Objective: To develop a diagnostic test that stratifies epileptic seizure (ES) from
psychogenic nonepileptic seizure (PNES) by developing a multimodal algorithm that
integrates plasma concentrations of selected immune response associated proteins and
patient clinical risk factors for seizure. Methods: Daily blood samples were collected from patients evaluated in the epilepsy
monitoring unit (EMU) within 24 hours after EEG confirmed ES or PNES and plasma was
isolated. Levels of 51 candidate plasma proteins were quantified using an automated,
multiplexed, sandwich ELISA and then integrated and analyzed using our diagnostic
algorithm. Results: A 51 protein multiplexed ELISA panel was used to determine the plasma
concentrations of ES patients, PNES patients, and healthy controls. A combination of
protein concentrations, TRAIL, ICAM-1, MCP-2, and TNF-R1 provided a probability that
a patient recently experienced a seizure with TRAIL and ICAM-1 higher in PNES than
ES, and MCP-2 and TNF-R1 higher in ES than PNES. The diagnostic algorithm yielded an
AUC of 0.94 ± 0.07, sensitivity of 82.6% (95% CI: 62.9-93.0), and specificity of
91.6% (95% CI: 74.2-97.7). Further, expanding the diagnostic algorithm to include
previously identified PNES risk factors enhanced diagnostic performance with AUC of
0.97 ± 0.05, sensitivity of 91.3% (95% CI: 73.2-97.6), and specificity of 95.8% (95%
CI: 79.8-99.3). Conclusions: These 4 plasma proteins could provide a rapid, cost-effective, and accurate
blood-based diagnostic test to confirm recent ES or PNES. Classification of Evidence: This study provides Class III evidence that variable levels of 4 plasma proteins,
when analyzed by a diagnostic algorithm, can distinguish PNES from ES with
sensitivity of 82.6% and specificity of 91.6%.
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Danger-Sensing/Patten Recognition Receptors and Neuroinflammation in Alzheimer's Disease. Int J Mol Sci 2020; 21:ijms21239036. [PMID: 33261147 PMCID: PMC7731137 DOI: 10.3390/ijms21239036] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 11/24/2020] [Accepted: 11/25/2020] [Indexed: 02/06/2023] Open
Abstract
Fibrillar aggregates and soluble oligomers of both Amyloid-β peptides (Aβs) and hyperphosphorylated Tau proteins (p-Tau-es), as well as a chronic neuroinflammation are the main drivers causing progressive neuronal losses and dementia in Alzheimer’s disease (AD). However, the underlying pathogenetic mechanisms are still much disputed. Several endogenous neurotoxic ligands, including Aβs, and/or p-Tau-es activate innate immunity-related danger-sensing/pattern recognition receptors (PPRs) thereby advancing AD’s neuroinflammation and progression. The major PRR families involved include scavenger, Toll-like, NOD-like, AIM2-like, RIG-like, and CLEC-2 receptors, plus the calcium-sensing receptor (CaSR). This quite intricate picture stresses the need to identify the pathogenetically topmost Aβ-activated PRR, whose signaling would trigger AD’s three main drivers and their intra-brain spread. In theory, the candidate might belong to any PRR family. However, results of preclinical studies using in vitro nontumorigenic human cortical neurons and astrocytes and in vivo AD-model animals have started converging on the CaSR as the pathogenetically upmost PRR candidate. In fact, the CaSR binds both Ca2+ and Aβs and promotes the spread of both Ca2+ dyshomeostasis and AD’s three main drivers, causing a progressive neurons’ death. Since CaSR’s negative allosteric modulators block all these effects, CaSR’s candidacy for topmost pathogenetic PRR has assumed a growing therapeutic potential worth clinical testing.
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