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Gaff J, Octaviana F, Jackaman C, Kamerman P, Papadimitriou J, Lee S, Mountford J, Price P. Expression in skin biopsies supports genetic evidence linking CAMKK2, P2X7R and P2X4R with HIV-associated sensory neuropathy. J Neurovirol 2023; 29:241-251. [PMID: 37166584 PMCID: PMC10404215 DOI: 10.1007/s13365-023-01134-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 04/05/2023] [Accepted: 04/07/2023] [Indexed: 05/12/2023]
Abstract
HIV-associated sensory neuropathy (HIV-SN) affects 14-38% of HIV+ individuals stable on therapy with no neurotoxic drugs. Polymorphisms in CAMKK2, P2X7R and P2X4R associated with altered risk of HIV-SN in Indonesian and South African patients. The role of CaMKK2 in neuronal repair makes this an attractive candidate, but a direct role for any protein is predicated on expression in affected tissues. Here, we describe expression of CaMKK2, P2X7R and P2X4R proteins in skin biopsies from the lower legs of HIV+ Indonesians with and without HIV-SN, and healthy controls (HC). HIV-SN was diagnosed using the Brief Peripheral Neuropathy Screen. Biopsies were stained to detect protein gene product 9.5 on nerve fibres and CaMKK2, P2X7R or P2X4R, and were examined using 3-colour sequential scanning confocal microscopy. Intraepidermal nerve fibre densities (IENFD) were lower in HIV+ donors than HC and correlated directly with nadir CD4 T-cell counts (r = 0.69, p = 0.004). However, IENFD counts were similar in HIV-SN+ and HIV-SN- donors (p = 0.19) and so did not define neuropathy. CaMKK2+ cells were located close to dermal and epidermal nerve fibres and were rare in HC and HIV-SN- donors, consistent with a role for the protein in nerve damage and/or repair. P2X7R was expressed by cells in blood vessels of HIV-SN- donors, but rarely in HC or HIV-SN+ donors. P2X4R expression by cells in the epidermal basal layer appeared greatest in HIV-SN+ donors. Overall, the differential expression of CaMKK2, P2X7R and P2X4R supports the genetic evidence of a role for these proteins in HIV-SN.
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Affiliation(s)
- Jessica Gaff
- Curtin Medical School, Curtin University, Bentley, 6102, Australia
| | - Fitri Octaviana
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia
- Neurology Department, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
| | - Connie Jackaman
- Curtin Medical School, Curtin University, Bentley, 6102, Australia
- Curtin Health Innovation Research Institute, Bentley, Australia
| | - Peter Kamerman
- School of Physiology, University of Witwatersrand, Johannesburg, South Africa
| | | | - Silvia Lee
- Curtin Medical School, Curtin University, Bentley, 6102, Australia
- Department of Microbiology, Pathwest Laboratory Medicine, Perth, Australia
| | | | - Patricia Price
- Curtin Medical School, Curtin University, Bentley, 6102, Australia.
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia.
- Curtin Health Innovation Research Institute, Bentley, Australia.
- School of Physiology, University of Witwatersrand, Johannesburg, South Africa.
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2
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Motwani L, Asif N, Patel A, Vedantam D, Poman DS. Neuropathy in Human Immunodeficiency Virus: A Review of the Underlying Pathogenesis and Treatment. Cureus 2022; 14:e25905. [PMID: 35844323 PMCID: PMC9278792 DOI: 10.7759/cureus.25905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2022] [Indexed: 11/05/2022] Open
Abstract
This article explores the various causes of the human immunodeficiency virus (HIV), and its associated neuropathy, including the effects of HIV on the nervous system and the long-standing therapy that is often provided to patients with HIV. Several studies regarding the neurotoxic effects of combined antiretroviral therapy (cART) and HIV were reviewed and various hypotheses were discussed. Furthermore, we present the nature of HIV-sensory neuropathy (HIV-SN) among different demographic populations and their subsequent risk factors predisposing them to this condition. It was observed that the incidence of the disease increases in increased survival of the patients as well as in males. Finally, the current approach to HIV-SN and its overlapping features with other causes of peripheral neuropathy have been discussed which demonstrates that a clinical examination is the most important clue for a healthcare professional to suspect the disease. Our main aim was to study the current perspectives and guidelines for diagnosing and managing a patient with HIV-SN to reduce disease prevalence and bring about a more aware frame of mind when following up with an HIV patient.
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Gaff J, Estiasari R, Diafiri D, Halstrom S, Kamerman P, Price P. Brief Report: Polymorphisms in CAMKK2 may Influence Domain-Specific Neurocognitive Function in HIV+ Indonesians Receiving ART. J Acquir Immune Defic Syndr 2022; 89:115-119. [PMID: 34878439 DOI: 10.1097/qai.0000000000002819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 08/12/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND Despite effective antiretroviral therapy (ART), milder forms of HIV-associated neurocognitive disorders remain prevalent and are characterized by neuroinflammation, synaptic dysfunction, and neuronal loss. METHODS We explore associations between neurocognitive impairment in HIV+ Indonesians and 17 polymorphisms in adjacent genes involved in inflammation and neuronal growth/repair pathways, P2X4R and CAMKK2. HIV+ Indonesians (n = 59) who had received ART for 12 months were assessed to derive Z-scores for the attention, fluency, memory, executive, and motor speed domains relative to local control subjects. These were used to determine total cognitive scores. RESULTS No alleles of P2X4R displayed significant associations with neurocognition in bivariate or multivariable analyses. In CAMKK2, rs2686344 influenced total cognitive scores in bivariate analyses (P = 0.04). Multivariable linear regression modeling independently associated rs2686344 with higher executive function Z-scores (P = 0.05) after adjusting for CD4 T-cell counts (adjusted R2 = 0.103, model P = 0.034), whereas rs1653588 associated with lower and rs1718120 (P = 0.05) with higher fluency Z-scores (P = 0.05) after adjusting for education and log10 HIV RNA copies/mL (adjusted R2 = 0.268, model P = 0.001). CONCLUSIONS Polymorphisms in CAMKK2 may influence neurocognitive outcomes in specific domains in HIV+ Indonesians receiving ART for 12 months.
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Affiliation(s)
- Jessica Gaff
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia
| | - Riwanti Estiasari
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia
- Neurology Department, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
| | - Dinda Diafiri
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia
- Neurology Department, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
| | - Samuel Halstrom
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia
- School of Medical and Biomedical Science, University of Queensland, Brisbane, Australia ; and
| | - Peter Kamerman
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia
- Brain Function Research Group, School of Physiology, University of Witwatersrand, Johannesburg, South Africa
| | - Patricia Price
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia
- Brain Function Research Group, School of Physiology, University of Witwatersrand, Johannesburg, South Africa
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4
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Gaff J, Estiasari R, Diafiri D, Halstrom S, Kamerman P, Price P. Neurocognitive outcomes in indonesians living with HIV are influenced by polymorphisms in the gene encoding purinergic P2X receptor 7. Brain Behav Immun Health 2021; 13:100220. [PMID: 34589739 PMCID: PMC8474153 DOI: 10.1016/j.bbih.2021.100220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/11/2021] [Accepted: 02/11/2021] [Indexed: 11/05/2022] Open
Abstract
The advent of effective antiretroviral therapy (ART) has decreased the prevalence and severity of HIV-associated neurocognitive disorders (HAND), but milder forms of HAND remain despite optimal treatment. Neuronal injury and loss due to inflammation may mediate HAND. P2X7R encodes purinergic P2X receptor 7 which influences neuroinflammatory pathways and carries polymorphisms associated with sensory neuropathy in HIV patients. We assessed associations between P2X7R polymorphisms and neurocognitive outcomes in Indonesian patients (n = 59) as they commenced ART and after 3, 6 and 12 months. Z-scores were calculated over 5 domains using local controls and evaluated as continuous variables. Optimal linear regression models identified polymorphisms influencing attention, memory, executive function, motor speed and total cognitive function at each time point. rs504677 was associated with lower executive and motor speed Z-scores at 0, 3, 6, and 12 months, and with memory at 0 and 12 months. Memory was positively influenced by carriage of the rs208296 minor allele at 0, 3 and 6 months and by carriage of the rs208307 minor allele at 0 and 12 months. Higher attention Z-scores associated with carriage of minor alleles of rs1653598 after 0 and 12 months. These also positively influenced executive function and motor speed after 0–6 months. This study identifies polymorphisms in P2X7R which influence domain-specific neurocognitive outcomes in HIV+ Indonesians prior to and shortly after commencing ART. This implicates purinergic P2X receptor 7 in the pathogenesis of HAND. Neurocognitive outcomes in HIV+ Indonesians were assessed over one year on ART. Overall scores were influenced by age, education and CD4 T-cell counts. Five intronic polymorphisms in P2X7R affected scores of selected domains. The influence of P2X7R polymorphisms varied over time on ART. P2X7R may influence neurocognitive changes on ART.
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Affiliation(s)
- Jessica Gaff
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia
| | - Riwanti Estiasari
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia.,Neurology Department, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
| | - Dinda Diafiri
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia.,Neurology Department, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
| | - Sam Halstrom
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia.,School of Medical and Biomedical Science, University of Queensland, Brisbane, Australia
| | - Peter Kamerman
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia.,Brain Function Research Group, School of Physiology, University of Witwatersrand, Johannesburg, South Africa
| | - Patricia Price
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia.,Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia.,Brain Function Research Group, School of Physiology, University of Witwatersrand, Johannesburg, South Africa
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5
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D'Amico D, Valdebenito S, Eugenin EA. The role of Pannexin-1 channels and extracellular ATP in the pathogenesis of the human immunodeficiency virus. Purinergic Signal 2021; 17:563-576. [PMID: 34542793 DOI: 10.1007/s11302-021-09817-3] [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: 06/03/2021] [Accepted: 08/03/2021] [Indexed: 10/20/2022] Open
Abstract
Only recently, the role of large ionic channels such as Pannexin-1 channels and Connexin hemichannels has been implicated in several physiological and pathological conditions, including HIV infection and associated comorbidities. These channels are in a closed stage in healthy conditions, but in pathological conditions including HIV, Pannexin-1 channels and Connexin hemichannels become open. Our data demonstrate that acute and chronic HIV infection induces channel opening (Pannexin and Connexin channels), ATP release into the extracellular space, and subsequent activation of purinergic receptors in immune and non-immune cells. We demonstrated that Pannexin and Connexin channels contribute to HIV infection and replication, the long-term survival of viral reservoirs, and comorbidities such as NeuroHIV. Here, we discuss the available data to support the participation of these channels in the HIV life cycle and the potential therapeutic approach to prevent HIV-associated comorbidities.
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Affiliation(s)
- Daniela D'Amico
- Department of Neuroscience , Cell Biology, and Anatomy, University of Texas Medical Branch (UTMB), Research Building 17, 105 11th Street, Galveston, TX, 77555, USA
| | - Silvana Valdebenito
- Department of Neuroscience , Cell Biology, and Anatomy, University of Texas Medical Branch (UTMB), Research Building 17, 105 11th Street, Galveston, TX, 77555, USA
| | - Eliseo A Eugenin
- Department of Neuroscience , Cell Biology, and Anatomy, University of Texas Medical Branch (UTMB), Research Building 17, 105 11th Street, Galveston, TX, 77555, USA.
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6
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Brief Report: Demographic and Genetic Associations With Markers of Small and Large Fiber Sensory Neuropathy in HIV Patients Treated Without Stavudine. J Acquir Immune Defic Syndr 2021; 85:612-616. [PMID: 32925363 DOI: 10.1097/qai.0000000000002503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Neurotoxic antiretroviral therapy (ART) such as stavudine has been now replaced with safer therapies, reducing the prevalence of neuropathy from 34% to 15% in HIV+ Indonesians. However, it is unclear whether the residual cases display damage to small or large nerve fibers and whether both are influenced by known risk factors, including alleles of CAMKK2 associated with neuropathy in HIV patients. The encoded protein influences the growth and repair of nerve fibers. HIV-positive adults on ART for >12 months without exposure to stavudine were screened for neuropathy using the AIDS Clinical Trials Group Brief Peripheral Neuropathy Screen (BPNS). Large fiber neuropathy was assessed by nerve conduction (NC) and small fiber neuropathy using stimulated skin wrinkling (SSW) applied to the fingers. CAMKK2 alleles were assessed by TaqMan OpenArray technology. Neuropathy diagnoses were more common with SSW than BPNS (49/173 vs 26/185, χ; P = 0.0009), with poor alignment between these outcomes (P = 0.60). NC and BPNS diagnosed neuropathy at similar frequencies (29/151 vs 26/185; P = 0.12) and were aligned (P < 0.0001). In bivariate analyses, all diagnoses were associated with patients' age and persistent HIV replication, with minor effects from CD4 T-cell counts and time on ART. CAMKK2 alleles associated with neuropathy diagnosed with BPNS and SSW but not NC. Multivariable analyses confirmed the importance of age and HIV replication, with distinct CAMKK2 polymorphisms affecting BPNS and SSW. Paradoxically, height was protective against skin wrinkling. Overall the data link CAMKK2 genotypes with small rather than large fiber damage. SSW may reflect pathology distinct from that identified using BPNS.
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7
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Kanellopoulos JM, Almeida-da-Silva CLC, Rüütel Boudinot S, Ojcius DM. Structural and Functional Features of the P2X4 Receptor: An Immunological Perspective. Front Immunol 2021; 12:645834. [PMID: 33897694 PMCID: PMC8059410 DOI: 10.3389/fimmu.2021.645834] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 03/04/2021] [Indexed: 12/14/2022] Open
Abstract
Extracellular nucleotides are important mediators of activation, triggering various responses through plasma membrane P2 and P1 receptors. P2 receptors are further subdivided into ionotropic P2X receptors and G protein-coupled P2Y receptors. P2X4 is an ATP-gated cation channel broadly expressed in most tissues of the body. Within the P2X family, P2X4 has a unique subcellular distribution, being preferentially localized in lysosomes. In these organelles, high ATP concentrations do not trigger P2X4 because of the low pH. However, when the pH increases to 7.4, P2X4 can be stimulated by intra-lysosomal ATP, which is in its active, tetra-anionic form. Elucidation of P2X4, P2X3 and P2X7 structures has shed some light on the functional differences between these purinergic receptors. The potential interaction between P2X4 and P2X7 has been extensively studied. Despite intensive effort, it has not been possible yet to determine whether P2X4 and P2X7 interact as heterotrimers or homotrimers at the plasma membrane. However, several publications have shown that functional interactions between P2X4 and P2X7 do occur. Importantly, these studies indicate that P2X4 potentiates P2X7-dependent activation of inflammasomes, leading to increased release of IL-1β and IL-18. The role of P2X4 in various diseases could be beneficial or deleterious even though the pathophysiological mechanisms involved are still poorly defined. However, in diseases whose physiopathology involves activation of the NLRP3 inflammasome, P2X4 was found to exacerbate severity of disease. The recent production of monoclonal antibodies specific for the human and mouse P2X4, some of which are endowed with agonist or antagonist properties, raises the possibility that they could be used therapeutically. Analysis of single nucleotide polymorphisms of the human P2RX4 gene has uncovered the association of P2RX4 gene variants with susceptibility to several human diseases.
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Affiliation(s)
- Jean M Kanellopoulos
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | | | - Sirje Rüütel Boudinot
- Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia
| | - David M Ojcius
- Department of Biomedical Sciences, University of the Pacific, Arthur A. Dugoni School of Dentistry, San Francisco, CA, United States
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8
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Chhatbar C, Prinz M. The roles of microglia in viral encephalitis: from sensome to therapeutic targeting. Cell Mol Immunol 2021; 18:250-258. [PMID: 33437050 PMCID: PMC7802409 DOI: 10.1038/s41423-020-00620-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/08/2020] [Indexed: 01/31/2023] Open
Abstract
Viral encephalitis is a devastating disease with high mortality, and survivors often suffer from severe neurological complications. Microglia are innate immune cells of the central nervous system (CNS) parenchyma whose turnover is reliant on local proliferation. Microglia express a diverse range of proteins, which allows them to continuously sense the environment and quickly react to changes. Under inflammatory conditions such as CNS viral infection, microglia promote innate and adaptive immune responses to protect the host. However, during viral infection, a dysregulated microglia-T-cell interplay may result in altered phagocytosis of neuronal synapses by microglia that causes neurocognitive impairment. In this review, we summarize the current knowledge on the role of microglia in viral encephalitis, propose questions to be answered in the future and suggest possible therapeutic targets.
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Affiliation(s)
- Chintan Chhatbar
- grid.5963.9Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Marco Prinz
- grid.5963.9Institute of Neuropathology, Medical Faculty, University of Freiburg, Freiburg, Germany ,grid.5963.9Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany ,grid.5963.9Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
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9
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Julian T, Rekatsina M, Shafique F, Zis P. Human immunodeficiency virus-related peripheral neuropathy: A systematic review and meta-analysis. Eur J Neurol 2020; 28:1420-1431. [PMID: 33226721 DOI: 10.1111/ene.14656] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 11/02/2020] [Accepted: 11/17/2020] [Indexed: 01/11/2023]
Abstract
BACKGROUND AND PURPOSE Human immunodeficiency virus (HIV)-associated neurological syndromes occur in affected individuals as a consequence of primary HIV infection, opportunistic infections, inflammation and as an adverse effect of some forms of antiretroviral treatment (ART). The aim of this systematic review was to establish the epidemiological characteristics, clinical features, pathogenetic mechanisms and risk factors of HIV-related peripheral neuropathy (PN). METHODS A systematic, computer-based search was conducted using the PubMed database. Data regarding the above parameters were extracted. Ninety-four articles were included in this review. RESULTS The most commonly described clinical presentation of HIV neuropathy is the distal predominantly sensory polyneuropathy. The primary pathology in HIVPN appears to be axonal rather than demyelinating. Age and treatment with medications belonging in the nucleoside analogue reverse transcriptase class are risk factors for developing HIV-related neuropathy. The pooled prevalence of PN in patients naïve to ARTs was established to be 29% (95% CI: 9%-62%) and increased to 38% (95% confidence interval [CI]: 29%-48%) when looking into patients at various stages of their disease. More than half of patients with HIV-related neuropathy are symptomatic (53%, 95% CI: 41%-63%). Management of HIV-related neuropathy is mainly symptomatic, although there is evidence that discontinuation of some types of ART, such as didanosine, can improve or resolve symptoms. CONCLUSIONS Human immunodeficiency virus-related neuropathy is common and represents a significant burden in patients' lives. Our understanding of the disease has grown over the last years, but there are unexplored areas requiring further study.
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Affiliation(s)
- Thomas Julian
- Medical School, The University of Sheffield, Broomhall, Sheffield, UK.,Academic Directorate of Neurosciences, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
| | - Martina Rekatsina
- Whipps Cross University Hospital, Barts Health NHS Trust, London, UK
| | - Faiza Shafique
- Academic Directorate of Neurosciences, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
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10
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A complete map of the Calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) signaling pathway. J Cell Commun Signal 2020; 15:283-290. [PMID: 33136287 DOI: 10.1007/s12079-020-00592-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 10/19/2020] [Indexed: 12/16/2022] Open
Abstract
Calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) is a serine/threonine-protein kinase belonging to the Ca2+/calmodulin-dependent protein kinase subfamily. CAMKK2 has an autocatalytic site, which gets exposed when Ca2+/calmodulin (CAM) binds to it. This results in autophosphorylation and complete activation of CAMKK2. The three major known downstream targets of CAMKK2 are 5'-adenosine monophosphate (AMP)-activated protein kinase (AMPKα), calcium/calmodulin-dependent protein kinase 1 (CAMK1) and calcium/calmodulin-dependent protein kinase 4 (CAMK4). Activation of these targets by CAMKK2 is important for the maintenance of different cellular and physiological processes within the cell. CAMKK2 is found to be important in neuronal development, bone remodeling, adipogenesis, and systemic glucose homeostasis, osteoclastgensis and postnatal myogensis. CAMKK2 is reported to be involved in pathologies like Duchenne muscular dystrophy, inflammation, osteoporosis and bone remodeling and is also reported to be overexpressed in prostate cancer, hepatic cancer, ovarian and gastric cancer. CAMKK2 is involved in increased cell proliferation and migration through CAMKK2/AMPK pathway in prostate cancer and activation of AKT in ovarian cancer. Although CAMKK2 is a molecule of great importance, a public resource of the CAMKK2 signaling pathway is currently lacking. Therefore, we carried out detailed data mining and documentation of the signaling events associated with CAMKK2 from published literature and developed an integrated reaction map of CAMKK2 signaling. This resulted in the cataloging of 285 reactions belonging to the CAMKK2 signaling pathway, which includes 33 protein-protein interactions, 74 post-translational modifications, 7 protein translocation events, and 22 activation/inhibition events. Besides, 124 gene regulation events and 25 activator/inhibitors involved in CAMKK2 activation were also cataloged. The CAMKK2 signaling pathway map data is made freely accessible through WikiPathway database ( https://www.wikipathways.org/index.php/Pathway:WP4874 ). We expect that data on a signaling map of CAMKK2 will provide the scientific community with an improved platform to facilitate further molecular as well as biomedical investigations on CAMKK2 and its utility in the development of biomarkers and therapeutic targets.
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11
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Puplampu P, Ganu V, Kenu E, Kudzi W, Adjei P, Grize L, Käser M. Peripheral neuropathy in patients with human immunodeficiency viral infection at a tertiary hospital in Ghana. J Neurovirol 2019; 25:464-474. [PMID: 31028691 PMCID: PMC6746675 DOI: 10.1007/s13365-019-00743-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 02/01/2019] [Accepted: 03/21/2019] [Indexed: 01/11/2023]
Abstract
Peripheral neuropathy (PN) is the most frequent neurological complication in people living with HIV/AIDS. Neurological damage was identified to not only be caused by the viral infection itself but also through neurotoxic antiretroviral therapy (ART). PN is associated with a variety of risk factors; however, detailed knowledge is scarce for sub-Saharan African populations, bearing among the highest HIV/AIDS infection burden.In a cross-sectional study, we assessed the prevalence of PN in 525 adult outpatients suffering from HIV/AIDS and admitted to the largest tertiary hospital in Ghana. Through a detailed questionnaire and clinical examination including neurologic assessment and laboratory blood sample testing, this study investigated associations of PN with demographic and health determinants and identified risk factors associated with sensory neuropathy.The prevalence of PN in the Ghanaian cohort was 17.7% and increased odd ratios (OR) when patients were taller (> 1.57 m; OR = 3.84; 95% CI 1.38-10.66) or reached the age > 34 years (p = 0.124). Respondents with longer education duration had significantly less PN (≥ 9 years of education; OR = 0.49; 95% CI 0.26-0.92). The study also identified significant association of PN to both waist and hip girth and neutrophil counts. Curiously, higher adjusted odd ratios (aOR) of PN of patients under ART treatment were observed when CD4 lymphocytes were elevated (aOR = 0.81; 95% CI 0.36-1.83 and aOR = 2.17; 95% CI 0.93-5.05, for 300 and 600 counts, respectively). For patients on ART, an increase of 10 CD4 cell count units increased their chance of developing PN by 1% (aOR = 1.01; 95% CI 1.00 to 1.03).Despite current drug application regulations, prevalence of PN is still unacceptably high in sub-Saharan African populations. Reduction in chronic morbidity through a health system with routine monitoring, early diagnosis and prompt intervention, and effective case management can improve people living with HIV/AIDS' quality of life.
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Affiliation(s)
- Peter Puplampu
- Department of Medicine, School of Medicine and Dentistry, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Vincent Ganu
- Department of Medicine, Korle-Bu Teaching Hospital, Accra, Ghana
| | - Ernest Kenu
- Department of Epidemiology, School of Public Health, University of Ghana, Accra, Ghana
| | - William Kudzi
- Centre for Tropical Clinical Pharmacology and Therapeutics, School of Medicine and Dentistry, College of Health Sciences, Accra, Ghana
| | - Patrick Adjei
- Department of Medicine, School of Medicine and Dentistry, College of Health Sciences, University of Ghana, Accra, Ghana
| | - Leticia Grize
- Swiss Tropical and Public Health Institute, Socinstr. 57, 4002, Basel, Switzerland
- University of Basel, Petersplatz 1, 4003, Basel, Switzerland
| | - Michael Käser
- Swiss Tropical and Public Health Institute, Socinstr. 57, 4002, Basel, Switzerland.
- University of Basel, Petersplatz 1, 4003, Basel, Switzerland.
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12
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Gaff J, Octaviana F, Ariyanto I, Cherry C, Laws SM, Price P. Polymorphisms in CAMKK2 associate with susceptibility to sensory neuropathy in HIV patients treated without stavudine. J Neurovirol 2019; 25:814-824. [PMID: 31309408 DOI: 10.1007/s13365-019-00771-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 05/14/2019] [Accepted: 06/03/2019] [Indexed: 01/20/2023]
Abstract
HIV-associated sensory neuropathy (HIV-SN) is a debilitating neurological complication of HIV infection potentiated by the antiretroviral drug stavudine. While stavudine is no longer used, HIV-SN now affects around 15% of HIV+ Indonesians. Here, we investigate whether polymorphisms within the P2X-block (P2X4R, P2X7R, CAMKK2) and/or ANAPC5 mark susceptibility to HIV-SN in this setting. As polymorphisms in these genes associated with HIV-SN in African HIV patients receiving stavudine, the comparison can identify mechanisms independent of stavudine. HIV patients who had never used stavudine (n = 202) attending clinics in Jakarta were screened for neuropathy using the AIDS Clinical Trials Group Brief Peripheral Neuropathy Screen. Open-array technology was used to type 48 polymorphisms spanning the four genes. Haplotypes were derived for each gene using fastPHASE. Haplogroups were constructed with median-joining methods. Multivariable models optimally predicting HIV-SN were based on factors achieving p < 0.2 in bivariate analyses. Minor alleles of three co-inherited polymorphisms in CAMKK2 (rs7975295*C, rs1560568*A, rs1132780*T) associated with a reduced prevalence of HIV-SN individually and after adjusting for lower CD4 T cell count and viremia (p = 0.0002, pseudo R2 = 0.11). The optimal model for haplotypes linked HIV-SN with viremia and lower current CD4 T cell count, plus CAMKK2 haplotypes 6 and 11 and P2X7R haplotypes 2 and 12 (p = 0.0002; pseudo R2 = 0.11). CAMKK2 haplogroup A (includes 16 haplotypes and all instances of rs7975295*C, rs1560568*A, rs1132780*T) associated with reduced rates of HIV-SN (p = 0.02, OR = 0.43 CI = 0.21-0.88). These findings support a protective role for these three alleles, suggesting a role in the pathogenesis of HIV-SN that is independent of stavudine.
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Affiliation(s)
- Jessica Gaff
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia
| | - Fitri Octaviana
- Neurology Department, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia.,Neurology Department, Cipto Mangunkusumo Hospital, Jakarta, Indonesia
| | - Ibnu Ariyanto
- Virology and Cancer Pathobiology Research Center, Universitas Indonesia, Jakarta, Indonesia
| | - Catherine Cherry
- Department of Infectious Diseases, Alfred Health and Monash University, Melbourne, Australia.,Burnet Institute, Melbourne, Australia
| | - Simon M Laws
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia.,Collaborative Genomics Group, School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Patricia Price
- School of Pharmacy and Biomedical Science, Curtin University, Bentley, Australia. .,Virology and Cancer Pathobiology Research Center, Universitas Indonesia, Jakarta, Indonesia. .,School of Physiology, University of Witwatersrand, Johannesburg, South Africa.
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Moketla MB, Wadley AL, Kamerman P, de Assis Rosa D. Pharmacogenetic variation influences sensory neuropathy occurrence in Southern Africans treated with stavudine-containing antiretroviral therapy. PLoS One 2018; 13:e0204111. [PMID: 30273369 PMCID: PMC6166924 DOI: 10.1371/journal.pone.0204111] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 09/03/2018] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The use of the HIV antiretroviral drug stavudine (d4T), a thymidine analogue, is associated with the development of mitochondrial toxicities such as sensory neuropathy (SN). Genetic variation in genes relating to d4T transport and metabolism, as well as genetic variation in the thymidine synthesis pathway, could influence occurrence of d4T-related toxicity. METHODS We examined this hypothesis in a cohort of HIV-positive South African adults exposed to d4T, including 143 cases with SN and 120 controls without SN. Ten SNPs in four genes associated with stavudine transport, and 16 SNPs in seven genes of the thymidine synthesis / phosphorylation pathway were genotyped using Agena mass spectrometry methods. Associations between sensory neuropathy and genetic variants were evaluated using PLINK by univariate and multivariable analyses. RESULTS Age and height were significantly associated with SN occurrence. Using logistic regression with age and height as covariates, and uncorrected empirical p-values, genetic variation in SLC28A1, SAMHD1, MTHFR and RRM2B was associated with SN in South Africans using d4T. CONCLUSION Variation in genes relating to d4T transport and metabolism, as well as genetic variation in the thymidine synthesis pathway may influence occurrence of d4T-related SN. These data contribute to the characterisation of African pharmacogenetic variation and its role in adverse response to antiretroviral therapy.
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Affiliation(s)
- Marvin Blessings Moketla
- School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Johannesburg, South Africa
| | - Antonia L. Wadley
- Brain Function Research Group, School of Physiology, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa
| | - Peter Kamerman
- Brain Function Research Group, School of Physiology, Faculty of Health Science, University of the Witwatersrand, Johannesburg, South Africa
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, Australia
| | - Debra de Assis Rosa
- School of Molecular and Cell Biology, Faculty of Science, University of the Witwatersrand, Johannesburg, South Africa
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Wodarski R, Bagdas D, Paris JJ, Pheby T, Toma W, Xu R, Damaj MI, Knapp PE, Rice AS, Hauser KF. Reduced intraepidermal nerve fibre density, glial activation, and sensory changes in HIV type-1 Tat-expressing female mice: involvement of Tat during early stages of HIV-associated painful sensory neuropathy. Pain Rep 2018; 3:e654. [PMID: 29922746 PMCID: PMC5999412 DOI: 10.1097/pr9.0000000000000654] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/19/2018] [Accepted: 03/17/2018] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION HIV infection is associated with chronic pain states, including sensory neuropathy, which affects greater than 40% of patients. OBJECTIVES AND METHODS To determine the impact of HIV-Tat induction on nociceptive behaviour in female mice conditionally expressing HIV Tat1-86 protein through a doxycycline (DOX)-driven glial fibrillary acidic protein promoter, intraepidermal nerve fibre density and immune cell activation in the dorsal root ganglion (DRG) and spinal cord were assessed by immunohistochemistry. Mice were assessed for mechanical and thermal sensitivity for 9 weeks using von-Frey and Hargreaves tests. RESULTS Intraepidermal nerve fibre density was significantly reduced after 6 weeks of Tat induction, similar to sensory neuropathy seen in clinical HIV infection. Tat induction through DOX caused a significant reduction in paw withdrawal thresholds in a time-dependent manner starting the 4th week after Tat induction. No changes in paw withdrawal latencies were seen in Tat(-) control mice lacking the tat transgene. Although reductions in paw withdrawal thresholds increased throughout the study, no significant change in spontaneous motor activity was observed. Spinal cord (cervical and lumbar), DRG, and hind paw skin were collected at 8 days and 6 weeks after Tat induction. HIV-Tat mRNA expression was significantly increased in lumbar DRG and skin samples 8 days after DOX treatment. Tat induced a significant increase in the number of Iba-1 positive cells at 6 weeks, but not after 8 days, of exposure. No differences in glial fibrillary acidic protein immunoreactivity were observed. CONCLUSION These results suggest that Tat protein contributes to painful HIV-related sensory neuropathy during the initial stages of the pathogenesis.
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Affiliation(s)
- Rachel Wodarski
- Pain Research Group, Department of Surgery and Cancer, Imperial College, Chelsea and Westminster Hospital Campus, London, United Kingdom
| | - Deniz Bagdas
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Jason J. Paris
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
- Department of BioMolecular Sciences, University of Mississippi, University, MS, USA
| | - Tim Pheby
- Pain Research Group, Department of Surgery and Cancer, Imperial College, Chelsea and Westminster Hospital Campus, London, United Kingdom
| | - Wisam Toma
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Ruqiang Xu
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
- School of Life Sciences, Zhengzhou University, Zhengzhou, Henan, China
| | - M. Imad Damaj
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
| | - Pamela E. Knapp
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
| | - Andrew S.C. Rice
- Pain Research Group, Department of Surgery and Cancer, Imperial College, Chelsea and Westminster Hospital Campus, London, United Kingdom
| | - Kurt F. Hauser
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA, USA
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA, USA
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Ex-vivo expression of chemokine receptors on cells surrounding cutaneous nerves in patients with HIV-associated sensory neuropathy. AIDS 2018; 32:431-441. [PMID: 29239897 DOI: 10.1097/qad.0000000000001714] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
OBJECTIVE HIV-associated sensory neuropathy (HIV-SN) remains common in HIV+ individuals receiving antiretroviral therapy (ART), even though neurotoxic antiretroviral drugs (e.g. stavudine) have been phased out of use. Accumulating evidence indicates that the neuropathy is immune-mediated. We hypothesize that chemokines produced locally in the skin promote migration of macrophages and T cells into the tissue, damaging cutaneous nerves causing HIV-SN. DESIGN We assessed chemokine receptor expression on infiltrating CD14 and CD3 cells around cutaneous nerves in standardized skin biopsies from HIV-SN+ patients (n = 5), HIV-SN- patients (n = 9) and healthy controls (n = 4). METHODS The AIDS Clinical Trials Group Brief Peripheral Neuropathy Screen was used to assess Indonesian HIV+ patients receiving ART without stavudine (case definition: bilateral presence of at least one symptom and at least one sign of neuropathy). Distal leg skin biopsies were stained to visualize chemokine receptors (CCR2, CCR5, CXCR3, CXCR4, CX3CR1), infiltrating CD3 and CD14 cells, and protein-gene-product 9.5 on nerves, using immunohistochemistry and 4-colour confocal microscopy. RESULTS Intraepidermal nerve fibre density was variable in patients without HIV-SN and generally lower in those with HIV-SN. CX3CR1 was more evident on CD14 cells whereas CCR2, CCR5, CXCR3 and CXCR4 were more common on CD3 cells. Expression of CX3CR1, CCR2 and CCR5 was more common in HIV-SN+ patients than those without HIV-SN. CXCR3 and CXCR4 were upregulated in all HIV+ patients, compared with healthy controls. CONCLUSION Inflammatory macrophages expressing CX3CR1 and T cells expressing CCR2 and CCR5 may participate in peripheral nerve damage leading to HIV-SN in HIV+ patients treated without stavudine. Further characterization of these cells is warranted.
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Gaff J, Halstrom S, Temple SEL, Baltic S, Kamerman P, Price P. Polymorphisms in P2X4R and CAMKK2 may affect TNFα production: Implications for a role in HIV-associated sensory neuropathy. Hum Immunol 2018; 79:224-227. [PMID: 29428485 DOI: 10.1016/j.humimm.2018.02.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 02/02/2018] [Accepted: 02/07/2018] [Indexed: 01/31/2023]
Abstract
Polymorphisms in P2X4R and CAMKK2 associate with susceptibility to HIV-associated sensory neuropathy (HIV-SN) - a condition likely mediated by TNFα. As single nucleotide polymorphisms (SNPs) and haplotypes of CAMKK2, and a neighbouring gene P2X4R, mark susceptibility to HIV-SN in South Africans living with HIV, we examined the relationship between P2X4R and CAMKK2 genotypes and TNFα production. Peripheral blood mononuclear cells from 129 healthy donors were stimulated with killed Escherichia coli, and concentrations of soluble TNFα were assessed. Their DNA was genotyped for 22 SNPs in P2X4R and CAMKK2. Three SNPs within P2X4R and two SNPs within CAMKK2 influenced concentrations of TNFα, but these SNP did not associate with risk for HIV-SN. This incongruence may reflect differences in P2X4R haplotypes present in Africans and Europeans. However some CAMKK2 haplotypes were found in both populations, so CAMKK2 polymorphisms may impact upon HIV-SN via effects of the protein on pathways other than TNFα.
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Affiliation(s)
- Jessica Gaff
- School of Biomedical Science, Curtin University, Perth, Australia
| | - Samuel Halstrom
- School of Biomedical Science, Curtin University, Perth, Australia; School of Medicine, University of Queensland, Brisbane, Australia
| | - Suzanna E L Temple
- Institute of Respiratory Health, University of Western Australia, Perth, Australia
| | - Svetlana Baltic
- Institute of Respiratory Health, University of Western Australia, Perth, Australia
| | - Peter Kamerman
- School of Biomedical Science, Curtin University, Perth, Australia; School of Physiology, University of the Witwatersrand, Johannesburg, South Africa
| | - Patricia Price
- School of Biomedical Science, Curtin University, Perth, Australia; School of Physiology, University of the Witwatersrand, Johannesburg, South Africa.
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Genetics of HIV-associated sensory neuropathy and related pain in Africans. J Neurovirol 2017; 23:511-519. [PMID: 28560631 DOI: 10.1007/s13365-017-0532-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Revised: 03/31/2017] [Accepted: 05/01/2017] [Indexed: 12/20/2022]
Abstract
Despite the use of safer antiretroviral medications, the rate of HIV-associated sensory neuropathy (HIV-SN), the most common neurological complication of HIV, remains high. This condition is often painful and has a negative effect on quality of life. Up to 90% of those with HIV-SN experience pain for which there is no effective analgesic treatment. Genetic factors are implicated, but there is a lack of a comprehensive body of research for African populations. This knowledge gap is even more pertinent as Africans are most affected by HIV. However, recent studies performed in Southern African populations have identified genes displaying potential as genetic markers for HIV-SN and HIV-SN-associated pain in Africans. Here, we review the published studies to describe current knowledge of genetic risk factors for this disease in Africa.
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Dmello DM, Ariyanto I, Estiasari R, Halstrom S, Gaff J, Lee S, Price P. Polymorphisms in IL10 may alter CD4 T-cell counts in Indonesian HIV patients beginning antiretroviral therapy. Hum Immunol 2017; 78:387-390. [PMID: 28263776 DOI: 10.1016/j.humimm.2017.03.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 03/01/2017] [Accepted: 03/01/2017] [Indexed: 12/22/2022]
Abstract
Interleukin 10 (IL-10) is a potent anti-inflammatory cytokine influenced by single nucleotide polymorphisms (SNP) located in upstream regulatory regions. Here we address the effects of five SNP (rs1518111, rs3021094, rs3024491, rs1800872 and rs1800871) on CD4 T-cell counts in Indonesian HIV patients assessed before ART and over 12months on treatment. Heterozygosity at rs1518111 or rs1800872 associated with low CD4 T-cell counts at all time points. Both alleles were carried in two haplotypes. Haplotype 21122 (present in 30% of participants) associated with low CD4 T-cell counts, whereas 21222 (in 6% of participants) did not. Hence untyped SNP(s) tagged by 21122 may depress CD4 T-cell counts. The association with heterozygosity suggests synergy with an allele from a haplotype lacking rs1518111 and/or rs1800872.
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Affiliation(s)
- Deane Maria Dmello
- School of Biomedical Science, Curtin University, Perth, Western Australia, Australia
| | - Ibnu Ariyanto
- Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia
| | | | - Samuel Halstrom
- School of Biomedical Science, Curtin University, Perth, Western Australia, Australia
| | - Jessica Gaff
- School of Biomedical Science, Curtin University, Perth, Western Australia, Australia
| | - Silvia Lee
- School of Biomedical Science, Curtin University, Perth, Western Australia, Australia
| | - Patricia Price
- School of Biomedical Science, Curtin University, Perth, Western Australia, Australia; Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia.
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A haplotype spanning P2X7R, P2X4R and CAMKK2 may mark susceptibility to pulmonary non-tuberculous mycobacterial disease. Immunogenetics 2017; 69:287-293. [PMID: 28233049 DOI: 10.1007/s00251-017-0972-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 01/21/2017] [Indexed: 01/15/2023]
Abstract
Despite widespread exposure to potentially pathogenic mycobacteria present in the soil and in domestic water supplies, it is not clear why only a small proportion of individuals contract pulmonary nontuberculous mycobacterial (NTM) infections. Here, we explore the impact of polymorphisms within three genes: P2X ligand gated ion channel 7 (P2X7R), P2X ligand gated ion channel 4 (P2X4R) and calcium/calmodulin-dependent protein kinase kinase 2 beta (CAMKK2) on susceptibility. Thirty single nucleotide polymorphisms (SNPs) were genotyped in NTM patients (n = 124) and healthy controls (n = 229). Weak associations were found between individual alleles in P2X7R and disease but were not significant in multivariate analyses adjusted to account for gender. Haplotypes spanning the three genes were derived using the fastPHASE algorithm. This yielded 27 haplotypes with frequencies >1% and accounting for 63.3% of the combined cohort. In univariate analyses, seven of these haplotypes displayed associations with NTM disease above our preliminary cut-off (p ≤ 0.20). When these were carried forward in a logistic regression model, gender and one haplotype (SH95) were independently associated with the disease (model p < 0.0001; R 2 = 0.05). Examination of individual alleles within these haplotypes implicated P2X7R and CAMKK2 in pathways affecting pulmonary NTM disease.
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