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Sinha S, Everaert K, Kheir GB, Roberts N, Solomon E, Belal M, Selai C, Perrouin-Verbe MA, Spicchiale CF, Wein A, Abrams P. Could a better understanding of the underlying pathophysiologies lead to more informed treatment choices in patients with lower urinary tract dysfunction due to an acontractile or underactive detrusor? ICI-RS 2023. Neurourol Urodyn 2024; 43:1381-1390. [PMID: 37960931 DOI: 10.1002/nau.25329] [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: 10/21/2023] [Accepted: 10/25/2023] [Indexed: 11/15/2023]
Abstract
INTRODUCTION The underlying pathophysiology behind a diagnosis of acontractile or underactive detrusor at invasive urodynamics is very heterogeneous. Lack of etiological classification currently limits the possibility of stratifying therapy. METHODS This subject was discussed at a think-tank on the subject at the International Consultation on Incontinence-Research Society held in Bristol, June 2023. This manuscript is a result of those deliberations and the subsequent discussions of the think-tank. RESULTS There are challenges in defining abnormalities of detrusor contraction with resultant implications for available evidence. Pathology at any level of the neuromuscular pathway can impair or prevent a detrusor voiding contraction. Attempts have been made to identify clinical markers that might predict an underactive detrusor but strong supporting evidence is lacking. Hence, a holistic approach to phenotyping requires specialized neuro-imaging as well as physiological investigations. Several general measures can help individuals with an abnormal detrusor contraction. The search for a molecule to enhance the detrusor voiding contraction remains elusive but there are promising new candidates. Neuromodulation can help select individuals but data is not well stratified by underlying etiology. Manipulation of central neurotransmitters might offer an alternate therapeutic option. CONCLUSIONS A better understanding of the underlying pathophysiologies behind an abnormality of the detrusor voiding contraction is needed for improving management. Towards this goal, the think-tank proposes a classification of the underactive detrusor that might help in selecting and reporting more well-defined patient cohorts.
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Affiliation(s)
- Sanjay Sinha
- Department of Urology, Apollo Hospital, Hyderabad, India
| | | | | | - Neil Roberts
- Division of Cell Matrix Biology and Regenerative Medicine, The University of Manchester, Bristol, UK
| | - Eskinder Solomon
- Department of Functional Urology, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Mohammed Belal
- Department of Urology, Queen Elizabeth Hospital, Birmingham, UK
| | - Caroline Selai
- UCL Department of Clinical and Movement Neurosciences, Queen Square Institute of Neurology, London, UK
| | | | | | - Alan Wein
- Department of Urology, Desai-Seth Institute of Urology, University of Miami, Miami, Florida, USA
| | - Paul Abrams
- Department of Urology, University of Bristol, Bristol, UK
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Chen Y, Vats A, Xi Y, Wolf-Johnston A, Clinger O, Arbuckle R, Dermond C, Li J, Stolze D, Sahel JA, Jackson E, Birder L. Oral 8-aminoguanine against age-related retinal degeneration. RESEARCH SQUARE 2024:rs.3.rs-4022389. [PMID: 38765984 PMCID: PMC11100887 DOI: 10.21203/rs.3.rs-4022389/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Visual decline in the elderly is often attributed to retinal aging, which predisposes the tissue to pathologies such as age-related macular degeneration. Currently, effective oral pharmacological interventions for retinal degeneration are limited. We present a novel oral intervention, 8-aminoguanine (8-AG), targeting age-related retinal degeneration, utilizing the aged Fischer 344 rat model. A low-dose 8-AG regimen (5 mg/kg body weight) via drinking water, beginning at 22 months for 8 weeks, demonstrated significant retinal preservation. This was evidenced by increased retinal thickness, improved photoreceptor integrity, and enhanced electroretinogram responses. 8-AG effectively reduced apoptosis, oxidative damage, and microglial/macrophage activation associated with aging retinae. Age-induced alterations in the retinal purine metabolome, characterized by elevated levels of inosine, hypoxanthine, and xanthine, were partially mitigated by 8-AG. Transcriptomics highlighted 8-AG's anti-inflammatory effects on innate and adaptive immune responses. Extended treatment to 17 weeks further amplified the retinal protective effects. Moreover, 8-AG showed temporary protective effects in the RhoP23H/+ mouse model of retinitis pigmentosa, reducing active microglia/macrophages. Our study positions 8-AG as a promising oral agent against retinal aging. Coupled with previous findings in diverse disease models, 8-AG emerges as a promising anti-aging compound with the capability to reverse common aging hallmarks.
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Andersson KE. Promising therapeutic targets for the treatment of urine storage dysfunction: what's the status? Expert Opin Ther Targets 2024; 28:251-258. [PMID: 38629152 DOI: 10.1080/14728222.2024.2344698] [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: 11/19/2023] [Accepted: 04/15/2024] [Indexed: 04/22/2024]
Abstract
INTRODUCTION Opinions differ on what drugs have both a rationale and a development potential for the treatment of bladder storage dysfunction. AREAS COVERED In the present review, the focus is given to small molecule blockers of TRP channels (TRPV1, TRPV4, TRPA1, and TRPM8), P2 × 3receptor antagonists, drugs against oxidative stress, antifibrosis agents, cyclic nucleotide - dependent pathways, and MaxiK±channel - gene therapy. EXPERT OPINION TRPV1 channel blockers produce hypothermia which seems to be a problem even with the most efficacious second-generation TRPV1 antagonists. This has so far precluded their application to urine storage disorders. Other TRP channel blockers with promising rationale have yet to be tested on the human lower urinary tract. The P2 × 3receptor antagonist, eliapixant, was tested in a randomized controlled clinical trial, was well tolerated but did not meet clinical efficacy endpoints. Antifibrosis agent still await application to the human lower urinary tract. New drug principles for oxidative stress, purine nucleoside phosphorylase inhibition, and NOX inhibition are still at an experimental stage, and so are soluble guanylate cyclase stimulators. Gene therapy with MaxiK±channels is still an interesting approach but no new trials seem to be in pipeline.
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Affiliation(s)
- Karl-Erik Andersson
- Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Winston Salem, NC, USA
- Department of Laboratory Medicine, Lund University, Lund, Sweden
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4
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Wolf-Johnston A, Ikeda Y, Zabbarova I, Kanai AJ, Bastacky S, Moldwin R, Stern JN, Jackson EK, Birder LA. Purine nucleoside phosphorylase inhibition is an effective approach for the treatment of chemical hemorrhagic cystitis. JCI Insight 2024; 9:e176103. [PMID: 38271096 PMCID: PMC10972598 DOI: 10.1172/jci.insight.176103] [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: 09/26/2023] [Accepted: 01/22/2024] [Indexed: 01/27/2024] Open
Abstract
Hemorrhagic cystitis may be induced by infection, radiation therapy, or medications or may be idiopathic. Along with hemorrhagic features, symptoms include urinary urgency and frequency, dysuria (painful urination), and visceral pain. Cystitis-induced visceral pain is one of the most challenging types of pain to treat, and an effective treatment would address a major unmet medical need. We assessed the efficacy of a purine nucleoside phosphorylase inhibitor, 8-aminoguanine (8-AG), for the treatment of hemorrhagic/ulcerative cystitis. Lower urinary tract (LUT) function and structure were assessed in adult Sprague-Dawley rats, treated chronically with cyclophosphamide (CYP; sacrificed day 8) and randomized to daily oral treatment with 8-AG (begun 14 days prior to CYP induction) or its vehicle. CYP-treated rats exhibited multiple abnormalities, including increased urinary frequency and neural mechanosensitivity, reduced bladder levels of inosine, urothelial inflammation/damage, and activation of spinal cord microglia, which is associated with pain hypersensitivity. 8-AG treatment of CYP-treated rats normalized all observed histological, structural, biochemical, and physiological abnormalities. In cystitis 8-AG improved function and reduced both pain and inflammation likely by increasing inosine, a tissue-protective purine metabolite. These findings demonstrate that 8-AG has translational potential for reducing pain and preventing bladder damage in cystitis-associated LUT dysfunctions.
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Affiliation(s)
| | - Youko Ikeda
- Renal-Electrolyte Division, Department of Medicine
| | | | - Anthony J Kanai
- Renal-Electrolyte Division, Department of Medicine
- Department of Pharmacology and Chemical Biology; and
| | - Sheldon Bastacky
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Robert Moldwin
- Arthur Smith Institute for Urology, Northwell Health, Zucker School of Medicine at Hofstra/Northwell, Lake Success, New York, USA
| | - Joel Nh Stern
- Arthur Smith Institute for Urology, Northwell Health, Zucker School of Medicine at Hofstra/Northwell, Lake Success, New York, USA
| | | | - Lori A Birder
- Renal-Electrolyte Division, Department of Medicine
- Department of Pharmacology and Chemical Biology; and
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5
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Hardy CC, Korstanje R. Aging and urinary control: Alterations in the brain-bladder axis. Aging Cell 2023; 22:e13990. [PMID: 37740454 PMCID: PMC10726905 DOI: 10.1111/acel.13990] [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: 07/12/2023] [Revised: 08/29/2023] [Accepted: 09/05/2023] [Indexed: 09/24/2023] Open
Abstract
Age-associated alterations in bladder control affect millions of older adults, with a heavy burden added to families both economically and in quality of life. Therapeutic options are limited with poor efficacy in older adults, lending to a growing need to address the gaps in our current understanding of urinary tract aging. This review summarizes the current knowledge of age-associated alterations in the structure and function of the brain-bladder axis and identifies important gaps in the field that have yet to be addressed. Urinary aging is associated with decreased tissue responsiveness, decreased control over the voiding reflex, signaling dysfunction along the brain-bladder axis, and structural changes within the bladder wall. Studies are needed to improve our understanding of how age affects the brain-bladder axis and identify genetic targets that correlate with functional outcomes.
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Jia Q, Zeng H, Li M, Tang J, Xiao N, Gao S, Li H, Zhang J, Zhang Z, Xie W. Binding asymmetry and conformational studies of the AtGSDA dimer. Comput Struct Biotechnol J 2023; 21:5515-5522. [PMID: 38022696 PMCID: PMC10663702 DOI: 10.1016/j.csbj.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/01/2023] [Accepted: 11/01/2023] [Indexed: 12/01/2023] Open
Abstract
Guanosine deaminase (GSDA) is an important deaminase that converts guanosine to xanthosine, a key intermediate in nitrogen recycling in plants. We previously solved complex structures of Arabidopsis thaliana GSDA bound by various ligands and examined its catalytic mechanism. Here, we report cocrystal structures of AtGSDA bound by inactive guanosine derivatives, which bind relatively weakly to the enzyme and mostly have poor binding geometries. The two protomers display unequal binding performances, and molecular dynamics simulation identified diverse conformations during the enzyme-ligand interactions. Moreover, intersubunit, tripartite salt bridges show conformational differences between the two protomers, possibly acting as "gating" systems for substrate binding and product release. Our structural and biochemical studies provide a comprehensive understanding of the enzymatic behavior of this intriguing enzyme.
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Affiliation(s)
- Qian Jia
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Hui Zeng
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Mingwei Li
- Division of Life Sciences and Medicine, and Biomedical Sciences and Health Laboratory of Anhui Province, University of Science and Technology of China, Hefei, Anhui 230026, PR China
| | - Jing Tang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Nan Xiao
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Shangfang Gao
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Huanxi Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Jinbing Zhang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
| | - Zhiyong Zhang
- MOE Key Laboratory for Membraneless Organelles & Cellular Dynamics, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, PR China
| | - Wei Xie
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, Guangdong 510006, People's Republic of China
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7
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Jackson EK, Tofovic SP, Chen Y, Birder LA. 8-Aminopurines in the Cardiovascular and Renal Systems and Beyond. Hypertension 2023; 80:2265-2279. [PMID: 37503660 PMCID: PMC10592300 DOI: 10.1161/hypertensionaha.123.20582] [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] [Indexed: 07/29/2023]
Abstract
Screening of compounds comprising 8-substituted guanine revealed that 8-aminoguanosine and 8-aminoguanine cause diuresis/natriuresis/glucosuria, yet decrease potassium excretion. Subsequent investigations demonstrated that 8-aminoguanosine's effects are mediated by its metabolite 8-aminoguanine. The mechanism by which 8-aminoguanine causes diuresis/natriuresis/glucosuria involves inhibition of PNPase (purine nucleoside phosphorylase), which increases renal interstitial inosine levels. Additional evidence suggests that inosine, via indirect or direct adenosine A2B receptor activation, increases renal medullary blood flow which enhances renal excretory function. Likely, 8-aminoguanine has pleiotropic actions that also alter renal excretory function. Indeed, the antikaliuretic effects of 8-aminoguanine are independent of PNPase inhibition. 8-Aminoguanine is an endogenous molecule; nitrosative stress leads to production of biomolecules containing 8-nitroguanine moieties. Degradation of these biomolecules releases 8-nitroguanosine and 8-nitro-2'-deoxyguanosine which are converted to 8-aminoguanine. Also, guanosine and guanine per se may contribute to 8-aminoguanine formation. 8-Aminoinosine, 8-aminohypoxanthine, and 8-aminoxanthine likewise induce diuresis/natriuresis/glucosuria, yet do not reduce potassium excretion. Thus, there are several pharmacologically active 8-aminopurines with nuanced effects on renal excretory function. Chronic treatment with 8-aminoguanine attenuates hypertension in deoxycorticosterone/salt rats, prevents strokes, and increases lifespan in Dahl salt-sensitive rats on a high salt diet and attenuates the metabolic syndrome in rats; 8-aminoguanosine retards progression of pulmonary hypertension in rats and anemia and organ damage in sickle cell mice. 8-Aminoguanine reverses age-associated lower urinary tract dysfunction and retinal degeneration. 8-Aminopurines represent a new class of agents (and potentially endogenous factors) that have beneficial effects on the cardiovascular system and kidneys and may turn back the clock in age-associated diseases.
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Affiliation(s)
- Edwin K. Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
| | - Stevan P. Tofovic
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
| | - Yuanyuan Chen
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
| | - Lori A. Birder
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
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8
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Prag HA, Murphy MP, Krieg T. Preventing mitochondrial reverse electron transport as a strategy for cardioprotection. Basic Res Cardiol 2023; 118:34. [PMID: 37639068 PMCID: PMC10462584 DOI: 10.1007/s00395-023-01002-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/04/2023] [Accepted: 08/06/2023] [Indexed: 08/29/2023]
Abstract
In the context of myocardial infarction, the burst of superoxide generated by reverse electron transport (RET) at complex I in mitochondria is a crucial trigger for damage during ischaemia/reperfusion (I/R) injury. Here we outline the necessary conditions for superoxide production by RET at complex I and how it can occur during reperfusion. In addition, we explore various pathways that are implicated in generating the conditions for RET to occur and suggest potential therapeutic strategies to target RET, aiming to achieve cardioprotection.
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Affiliation(s)
- Hiran A Prag
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK.
| | - Michael P Murphy
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK.
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge, CB2 0XY, UK.
| | - Thomas Krieg
- Department of Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK.
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9
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Persaud AK, Bernier MC, Massey MA, Agrawal S, Kaur T, Nayak D, Xie Z, Weadick B, Raj R, Hill K, Abbott N, Joshi A, Anabtawi N, Bryant C, Somogyi A, Cruz-Monserrate Z, Amari F, Coppola V, Sparreboom A, Baker SD, Unadkat JD, Phelps MA, Govindarajan R. Increased renal elimination of endogenous and synthetic pyrimidine nucleosides in concentrative nucleoside transporter 1 deficient mice. Nat Commun 2023; 14:3175. [PMID: 37264059 PMCID: PMC10235067 DOI: 10.1038/s41467-023-38789-8] [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: 03/31/2022] [Accepted: 05/16/2023] [Indexed: 06/03/2023] Open
Abstract
Concentrative nucleoside transporters (CNTs) are active nucleoside influx systems, but their in vivo roles are poorly defined. By generating CNT1 knockout (KO) mice, here we identify a role of CNT1 in the renal reabsorption of nucleosides. Deletion of CNT1 in mice increases the urinary excretion of endogenous pyrimidine nucleosides with compensatory alterations in purine nucleoside metabolism. In addition, CNT1 KO mice exhibits high urinary excretion of the nucleoside analog gemcitabine (dFdC), which results in poor tumor growth control in CNT1 KO mice harboring syngeneic pancreatic tumors. Interestingly, increasing the dFdC dose to attain an area under the concentration-time curve level equivalent to that achieved by wild-type (WT) mice rescues antitumor efficacy. The findings provide new insights into how CNT1 regulates reabsorption of endogenous and synthetic nucleosides in murine kidneys and suggest that the functional status of CNTs may account for the optimal action of pyrimidine nucleoside analog therapeutics in humans.
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Affiliation(s)
- Avinash K Persaud
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Matthew C Bernier
- Campus Chemical Instrument Center Mass Spectrometry and Proteomics Facility, The Ohio State University, Columbus, OH, 43210, USA
| | - Michael A Massey
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
- The Center for Life Sciences Education, College of Arts and Sciences, The Ohio State University, Columbus, OH, 43210, USA
| | - Shipra Agrawal
- Division of Nephrology & Hypertension, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Tejinder Kaur
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Debasis Nayak
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Zhiliang Xie
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Brenna Weadick
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Ruchika Raj
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Kasey Hill
- Pharmacoanalytic Shared Resource (PhASR), The Ohio State University, Columbus, OH, 43205, USA
| | - Nicole Abbott
- Pharmacoanalytic Shared Resource (PhASR), The Ohio State University, Columbus, OH, 43205, USA
| | - Arnav Joshi
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Nadeen Anabtawi
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Claire Bryant
- Center for Clinical & Translational Research, Nationwide Children's Hospital, Columbus, OH, 43210, USA
| | - Arpad Somogyi
- Campus Chemical Instrument Center Mass Spectrometry and Proteomics Facility, The Ohio State University, Columbus, OH, 43210, USA
| | - Zobeida Cruz-Monserrate
- Division of Gastroenterology, Hepatology, and Nutrition, College of Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Foued Amari
- Genetically Engineered Mouse Modeling Core, Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, 43210, USA
| | - Vincenzo Coppola
- Genetically Engineered Mouse Modeling Core, Ohio State University Comprehensive Cancer Center, The Ohio State University, Columbus, OH, 43210, USA
- Department of Cancer Biology and Genetics, College of Medicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Alex Sparreboom
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Sharyn D Baker
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
| | - Jashvant D Unadkat
- Department of Pharmaceutics, College of Pharmacy, University of Washington, Seattle, WA, 98195, USA
- Translational Therapeutics, Ohio State University Comprehensive Cancer Center, Ohio State University, Columbus, OH, 43210, USA
| | - Mitch A Phelps
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA
- Pharmacoanalytic Shared Resource (PhASR), The Ohio State University, Columbus, OH, 43205, USA
| | - Rajgopal Govindarajan
- Division of Pharmaceutics & Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA.
- Translational Therapeutics, Ohio State University Comprehensive Cancer Center, Ohio State University, Columbus, OH, 43210, USA.
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Kanai A, Andersson KE, Birder L, Fry C. Soluble Guanylate Cyclase Activators to Treat Benign Prostatic Hyperplasia and associated LUTS. CONTINENCE (AMSTERDAM, NETHERLANDS) 2023; 6:100699. [PMID: 37389026 PMCID: PMC10310070 DOI: 10.1016/j.cont.2023.100699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
This review summarises the presentations during a workshop session entitled "The Use of Soluble Guanylate Cyclase Activators to Treat Benign Prostatic Hyperplasia, Obstruction and Fibrosis - Mechanistic Concepts and Clinical Implications" at the International Continence Society (ICS) 2021 Melbourne Virtual meeting. Benign prostatic hyperplasia (BPH) is a highly prevalent condition that can result in bladder outflow obstruction (BOO) and development of lower urinary tract symptoms (LUTS), and by 80 years of age is present in about 75% of men. Current pharmacological therapies include α-adrenoceptor antagonists, 5α-reductase inhibitors, and the phosphodiesterase type 5 (PDE5) inhibitor, tadalafil. The efficacy of tadalafil suggests a role for nitric oxide (NO•) through activation of soluble guanylate cyclase (sGC) and production of cyclic guanosine 3'5'-monophosphate (cGMP), a cyclic nucleotide that relaxes smooth muscle, reduces neurotransmitter release and also acts as an antifibrotic agent. Patient refractoriness to tadalafil may be, for example, due to sGC inactivation due to oxidative stress. The workshop discussed the superiority of cinaciguat, an sGC activator that functions even when the enzyme is oxidised, over PDE5 inhibitors, and potentially its use in combination with agents that reduce formation of reactive oxygen species.
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Affiliation(s)
- A.J. Kanai
- University of Pittsburgh, Department of Medicine, Renal-Electrolyte Division, USA
| | - K.-E. Andersson
- Lund University, Division of Clinical Chemistry and Pharmacology, Lund, Sweden
| | - L.A. Birder
- University of Pittsburgh, Department of Medicine, Renal-Electrolyte Division, USA
| | - C.H. Fry
- University of Bristol, School of Physiology, Pharmacology, and Neuroscience, UK
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Sun XL, Chen ZH, Guo X, Wang J, Ge M, Wong SZH, Wang T, Li S, Yao M, Johnston LA, Wu QF. Stem cell competition driven by the Axin2-p53 axis controls brain size during murine development. Dev Cell 2023; 58:744-759.e11. [PMID: 37054704 DOI: 10.1016/j.devcel.2023.03.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 01/08/2023] [Accepted: 03/20/2023] [Indexed: 04/15/2023]
Abstract
Cell competition acts as a quality-control mechanism that eliminates cells less fit than their neighbors to optimize organ development. Whether and how competitive interactions occur between neural progenitor cells (NPCs) in the developing brain remains unknown. Here, we show that endogenous cell competition occurs and intrinsically correlates with the Axin2 expression level during normal brain development. Induction of genetic mosaicism predisposes Axin2-deficient NPCs to behave as "losers" in mice and undergo apoptotic elimination, but homogeneous ablation of Axin2 does not promote cell death. Mechanistically, Axin2 suppresses the p53 signaling pathway at the post-transcriptional level to maintain cell fitness, and Axin2-deficient cell elimination requires p53-dependent signaling. Furthermore, mosaic Trp53 deletion confers a "winner" status to p53-deficient cells that outcompete their neighbors. Conditional loss of both Axin2 and Trp53 increases cortical area and thickness, suggesting that the Axin2-p53 axis may coordinate to survey cell fitness, regulate natural cell competition, and optimize brain size during neurodevelopment.
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Affiliation(s)
- Xue-Lian Sun
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Zhen-Hua Chen
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Xize Guo
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Jingjing Wang
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Mengmeng Ge
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Samuel Zheng Hao Wong
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Ting Wang
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Si Li
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Mingze Yao
- Institutes of Biomedical Sciences, Shanxi University, Taiyuan 030006, China
| | - Laura A Johnston
- Department of Genetics and Development, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Qing-Feng Wu
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100101, China; Beijing Children's Hospital, Capital Medical University, Beijing 100045, China; Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Beijing 100101, China.
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Tofovic SP. Purine Nucleoside Phosphorylase: A New Pharmacological Target in Sickle Cell Disease and Hemolytic Vasculopathy. Med Hypotheses 2023. [DOI: 10.1016/j.mehy.2023.111045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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Overactive Bladder and Cognitive Impairment: The American Urogynecologic Society and Pelvic Floor Disorders Research Foundation State-of-the-Science Conference Summary Report. UROGYNECOLOGY (HAGERSTOWN, MD.) 2023; 29:S1-S19. [PMID: 36548636 DOI: 10.1097/spv.0000000000001272] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
IMPORTANCE Overactive bladder (OAB) is prevalent in older adults in whom management is complicated by comorbidities and greater vulnerability to the cognitive effects of antimuscarinic medications. OBJECTIVES The aim of this study is to provide a comprehensive evidence-based summary of the 2021 State-of-the-Science (SOS) conference and a multidisciplinary expert literature review on OAB and cognitive impairment. STUDY DESIGN The American Urogynecologic Society and the Pelvic Floor Disorders Research Foundation convened a 3-day collaborative conference. Experts from multidisciplinary fields examined cognitive function, higher neural control of the OAB patient, risk factors for cognitive impairment in older patients, cognitive effects of antimuscarinic medications for OAB treatment, OAB phenotyping, conservative and advanced OAB therapies, and the need for a multidisciplinary approach to person-centered treatment. Translational topics included the blood-brain barrier, purine metabolome, mechanotransduction, and gene therapy for OAB targets. RESULTS Research surrounding OAB treatment efficacy in cognitively impaired individuals is limited. Short- and long-term outcomes regarding antimuscarinic effects on cognition are mixed; however, greater anticholinergic burden and duration of use influence risk. Oxybutynin is most consistently associated with negative cognitive effects in short-term, prospective studies. Although data are limited, beta-adrenergic agonists do not appear to confer the same cognitive risk. CONCLUSIONS The 2021 SOS summary report provides a comprehensive review of the fundamental, translational, and clinical research on OAB with emphasis on cognitive impairment risks to antimuscarinic medications. Duration of use and antimuscarinic type, specifically oxybutynin when examining OAB treatments, appears to have the most cognitive impact; however, conclusions are limited by the primarily cognitively intact population studied. Given current evidence, it appears prudent to minimize anticholinergic burden by emphasizing nonantimuscarinic therapeutic regimens in the older population and/or those with cognitive impairment.
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Evidence-Informed, Interdisciplinary, Multidimensional Action Plan to Advance Overactive Bladder Research and Treatment Initiatives: Directives From State-of-the-Science Conference on Overactive Bladder and Cognitive Impairment. UROGYNECOLOGY (HAGERSTOWN, MD.) 2023; 29:S20-S39. [PMID: 36548637 DOI: 10.1097/spv.0000000000001274] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
ABSTRACT This article outlines an evidence-informed, interdisciplinary, multidimensional, comprehensive action plan for the American Urogynecologic Society to improve care of women with overactive bladder (OAB) while minimizing treatment-related adverse events, including cognitive impairment. It is a "call to action" to advance basic, translational, and clinical research and summarizes initiatives developed at the State-of-the-Science Conference on OAB and Cognitive Impairment to (1) develop framework for a new OAB treatment approach in women, (2) define research gaps and future research priorities, (3) champion health equity and diversity considerations in OAB treatment, (4) foster community and promote education to remove stigma surrounding OAB and urinary incontinence, and (5) elevate visibility and impact of OAB, by creating partnerships through education and engagement with health care professionals, industry, private and public payers, funding agencies, and policymakers.
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Birder LA, Jackson EK. Purine nucleoside phosphorylase as a target to treat age-associated lower urinary tract dysfunction. Nat Rev Urol 2022; 19:681-687. [PMID: 36071153 PMCID: PMC9842101 DOI: 10.1038/s41585-022-00642-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2022] [Indexed: 01/18/2023]
Abstract
The lower urinary tract (LUT), including the bladder, urethra and external striated muscle, becomes dysfunctional with age; consequently, many older individuals suffer from lower urinary tract disorders (LUTDs). By compromising urine storage and voiding, LUTDs degrade quality of life for millions of individuals worldwide. Treatments for LUTDs have been disappointing, frustrating both patients and their physicians; however, emerging evidence suggests that partial inhibition of the enzyme purine nucleoside phosphorylase (PNPase) with 8-aminoguanine (an endogenous PNPase inhibitor that moderately reduces PNPase activity) reverses age-associated defects in the LUT and restores the LUT to that of a younger state. Thus, 8-aminoguanine improves LUT biochemistry, structure and function by rebalancing the LUT purine metabolome, making 8-aminoguanine a novel potential treatment for LUTDs.
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Affiliation(s)
- Lori A Birder
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| | - Edwin K Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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16
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Jackson EK, Menshikova EV, Ritov VB, Mi Z, Birder LA. 8-Aminoinosine and 8-Aminohypoxanthine Inhibit Purine Nucleoside Phosphorylase and Exert Diuretic and Natriuretic Activity. J Pharmacol Exp Ther 2022; 382:135-148. [PMID: 35609923 PMCID: PMC9639651 DOI: 10.1124/jpet.122.001221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 05/12/2022] [Indexed: 01/01/2023] Open
Abstract
8-Aminoguanine and 8-aminoguanosine (via metabolism to 8-aminoguanine) are endogenous 8-aminopurines that induce diuresis, natriuresis, and glucosuria by inhibiting purine nucleoside phosphorylase (PNPase); moreover, both 8-aminopurines cause antikaliuresis by other mechanisms. Because 8-aminoinosine and 8-aminohypoxanthine are structurally similar to 8-aminoguanosine and 8-aminoguanine, respectively, we sought to define their renal excretory effects. First, we compared the ability of 8-aminoguanine, 8-aminohypoxanthine, and 8-aminoinosine to inhibit recombinant PNPase. These compounds inhibited PNPase with a potency order of 8-aminoguanine > 8-aminohypoxanthine = 8-aminoinosine. Additional studies showed that 8-aminoinosine is a competitive substrate that is metabolized to a competitive PNPase inhibitor, namely 8-aminohypoxanthine. Administration of each 8-aminopurine (33.5 µmol/kg) reduced the guanine-to-guanosine and hypoxanthine-to-inosine ratios in urine, a finding confirming their ability to inhibit PNPase in vivo. All three 8-aminopurines induced diuresis, natriuresis, and glucosuria; however, the glucosuric effects of 8-aminohypoxanthine and 8-aminoinosine were less pronounced than those of 8-aminoguanine. Neither 8-aminohypoxanthine nor 8-aminoinosine altered potassium excretion, whereas 8-aminoguanine caused antikaliuresis. In vivo administration of 8-aminoinosine increased 8-aminohypoxanthine excretion, indicating that 8-aminohypoxanthine mediates, in part, the effects of 8-aminoinosine. Finally, 8-aminohypoxanthine was metabolized to 8-aminoxanthine by xanthine oxidase. Using ultraperformance liquid chromatography-tandem mass spectrometry, we identified 8-aminoinosine as an endogenous 8-aminopurine. In conclusion, 8-aminopurines have useful pharmacological profiles. To induce diuresis, natriuresis, glucosuria, and antikaliuresis, 8-aminoguanine (or its prodrug 8-aminoguanosine) would be preferred. If only diuresis and natriuresis, without marked glucosuria or antikaliuresis, is desired, 8-aminohypoxanthine or 8-aminoinosine might be useful. Finally, here we report the in vivo existence of another pharmacologically active 8-aminopurine, namely 8-aminoinosine. SIGNIFICANCE STATEMENT: Here, we report that a family of 8-aminopurines affects renal excretory function: effects that may be useful for treating multiple diseases including hypertension, heart failure, and chronic kidney disease. For diuresis and natriuresis accompanied by glucosuria and antikaliuresis, 8-aminoguanine (or its prodrug 8-aminoguanosine) would be useful; if only diuresis and natriuresis is called for, 8-aminohypoxanthine or 8-aminoinosine would be useful. Previously, we identified 8-aminoguanine and 8-aminoguanosine as endogenous 8-aminopurines; here, we extend the family of endogenous 8-aminopurines to include 8-aminoinosine.
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Affiliation(s)
- Edwin K Jackson
- Department of Pharmacology and Chemical Biology (E.K.J., E.V.M., V.B.R., Z.M.) and Department of Medicine (L.A.B.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Elizabeth V Menshikova
- Department of Pharmacology and Chemical Biology (E.K.J., E.V.M., V.B.R., Z.M.) and Department of Medicine (L.A.B.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Vladimir B Ritov
- Department of Pharmacology and Chemical Biology (E.K.J., E.V.M., V.B.R., Z.M.) and Department of Medicine (L.A.B.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Zaichuan Mi
- Department of Pharmacology and Chemical Biology (E.K.J., E.V.M., V.B.R., Z.M.) and Department of Medicine (L.A.B.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Lori A Birder
- Department of Pharmacology and Chemical Biology (E.K.J., E.V.M., V.B.R., Z.M.) and Department of Medicine (L.A.B.), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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de Rijk MM, Wolf-Johnston A, Kullmann AF, Taiclet S, Kanai AJ, Shiva S, Birder LA. Aging-Associated Changes in Oxidative Stress Negatively Impacts the Urinary Bladder Urothelium. Int Neurourol J 2022; 26:111-118. [PMID: 35793989 PMCID: PMC9260322 DOI: 10.5213/inj.2142224.112] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 10/18/2020] [Indexed: 12/01/2022] Open
Abstract
PURPOSE Lower urinary tract symptoms are known to significantly increase with age, negatively impacting quality of life and self-reliance. The urothelium fulfills crucial tasks, serving as a barrier protecting the underlying bladder tissue from the harsh chemical composition of urine, and exhibits signaling properties via the release of mediators within the bladder wall that affect bladder functioning. Aging is associated with detrimental changes in cellular health, in part by increasing oxidative stress in the bladder mucosa, and more specifically the urothelium. This, in turn, may impact urothelial mitochondrial health and bioenergetics. METHODS We collected mucosal tissue samples from both young (3-4 months old) and aged (25-30 months old) rats. Tissue was evaluated for p21-Arc, nitrotyrosine, and cytochrome C expression by western immunoblotting. Urothelial cells were cultured for single-cell imaging to analyze basal levels of reactive oxygen species and the mitochondrial membrane potential. Mitochondrial bioenergetics and cellular respiration were investigated by the Seahorse assay, and measurements of adenosine triphosphate release were made using the luciferin-luciferase assay. RESULTS Aging was associated with a significant increase in biomarkers of cellular senescence, oxidative stress, and basal levels of reactive oxygen species. The mitochondrial membrane potential was significantly lower in urothelial cell cultures from aged animals, and cultures from aged animals showed a significant decrease in mitochondrial bioenergetics. CONCLUSION Aging-related increases in oxidative stress and excessive reactive oxygen species may be contributing factors underlying lower urinary tract symptoms in older adults. The mechanisms outlined in this study could be utilized to identify novel pharmaceutical targets to improve aging-associated bladder dysfunction.
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Affiliation(s)
- Mathijs M. de Rijk
- Department of Urology, School for Mental Health and Neuroscience, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, The Netherlands
- Department of Urology, Maastricht University Medical Center+ (MUMC+), Maastricht, The Netherlands
| | - Amanda Wolf-Johnston
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Aura F. Kullmann
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Stephanie Taiclet
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Anthony J. Kanai
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Sruti Shiva
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Lori A. Birder
- Department of Medicine, Renal-Electrolyte Division, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Jackson EK, Menshikova EV, Ritov VB, Gillespie DG, Mi Z. Biochemical Pathways of 8-Aminoguanine Production In Sprague-Dawley and Dahl Salt-Sensitive Rats. Biochem Pharmacol 2022; 201:115076. [PMID: 35551915 DOI: 10.1016/j.bcp.2022.115076] [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: 03/01/2022] [Revised: 04/30/2022] [Accepted: 05/03/2022] [Indexed: 11/02/2022]
Abstract
BACKGROUND 8-Aminoguanine exerts natriuretic and antihypertensive activity. Whether and how "free" 8-aminoguanine exists in vivo is unclear. Because 8-nitroguanosine is naturally occurring, we tested the hypothesis that 8-aminoguanine can arise from: pathway 1, 8-nitroguanosine→8-aminoguanosine→8-aminoguanine; and pathway 2, 8-nitroguanosine→8-nitroguanine→8-aminoguanine. METHODS 8-Aminoguanine biosynthesis was explored in rats using renal microdialysis, mass spectrometry and enzyme kinetics. RESULTS In Sprague-Dawley rats, 8-nitroguanosine infusions increased kidney levels of 8-nitroguanine, 8-aminoguanosine and 8-aminoguanine; 8-nitroguanine infusions increased 8-aminoguanine. Purine nucleoside phosphorylase (PNPase) converted 8-nitroguanosine to 8-nitroguanine and 8-aminoguanosine to 8-aminoguanine. Forodesine (PNPase inhibitor) reduced metabolism of 8-nitroguanosine by pathway 2 and shunted metabolism of 8-nitroguanosine to 8-aminoguanosine. In Dahl salt-sensitive rats, 8-nitroguanosine infusions increased kidney levels of 8-nitroguanine, 8-aminoguanosine and 8-aminoguanine. These results indicate that both pathways 1 and 2 participate in the biosynthesis of 8-aminoguanine in Sprague-Dawley and Dahl rats. Endogenous 8-aminoguanine in kidneys and urine were elevated many-fold in Dahl, compared to Sprague-Dawley, rats. The increased levels of 8-aminoguanine in Dahl rats were not due to alterations in pathways 1 and 2 but were associated with increased urine levels of endogenous 8-nitroguanosine suggesting that the "upstream" production of 8-nitroguanosine was increased in Dahl rats. Dahl rats are known to have high levels of peroxynitrite, and peroxynitrite is known to nitrate guanosine in biomolecules. Here we confirm that a peroxynitrite donor increases kidney levels of 8-aminoguanine. CONCLUSION 8-Aminoguanine occurs naturally via two distinct pathways and kidney levels of 8-aminoguanine are increased in Dahl rats, likely due to increased production of 8-nitroguanosine, a by-product of peroxynitrite chemistry.
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Affiliation(s)
- Edwin K Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219.
| | - Elizabeth V Menshikova
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
| | - Vladimir B Ritov
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
| | - Delbert G Gillespie
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
| | - Zaichuan Mi
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15219
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19
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Hardy CC. The Aged Lower Urinary Tract: Deficits in Neural Control Mechanisms. FRONTIERS IN AGING 2021; 2:791833. [PMID: 35821993 PMCID: PMC9261385 DOI: 10.3389/fragi.2021.791833] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 11/16/2021] [Indexed: 11/13/2022]
Abstract
Bothersome urinary symptoms plague many older adults and disproportionally affect women. Underreporting of symptoms and general stigma/embarrassment associated with incontinence has negatively impacted the availability of treatments, as research cannot be championed if the severity of the problem is not apparent. Available therapeutics have limited efficacy and are often not recommended in aged patients. Lower urinary tract function has a long and rich history in animal studies; while much of the underlying anatomy has been described, including neural control mechanisms, the impact of aging has only just begun to be addressed. Recent work has provided strong evidence that neural control over micturition is significantly impacted by aging processes. This mini review discusses recent findings regarding how aging impacts the neural control mechanisms of micturition.
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Affiliation(s)
- Cara C. Hardy
- UConn Center on Aging, UConn Health, Farmington, CT, United States
- Department of Surgery, University of Connecticut SOM, UConn Health, Farmington, CT, United States
- CT Institute for the Brain and Cognitive Sciences, University of Connecticut, Storrs, CT, United States
- *Correspondence: Cara C. Hardy,
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Birder LA, Jackson EK. Dysregulated Purine Metabolism Contributes to Age-Associated Lower Urinary Tract Dysfunctions. ADVANCES IN GERIATRIC MEDICINE AND RESEARCH 2021; 3:e210018. [PMID: 34676378 PMCID: PMC8527459 DOI: 10.20900/agmr20210018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lower urinary tract (LUT) dysfunction is common in the older adult. Aging is associated with a number of both storage and voiding problems which are classified into syndromes with overlapping symptoms. Despite the prevalence and consequences of these syndromes, LUT disorders continue to be undertreated as few therapeutic options exist. Here, we propose that dysregulated metabolism of purine nucleotides results in an accumulation of uro-damaging hypoxanthine (a source of reactive oxygen species or ROS), which provides a mechanism for defects in sensory signaling and contractility, culminating in abnormal urodynamic behavior.
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Affiliation(s)
- Lori A. Birder
- Renal-Electrolyte Division, Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh PA 15261, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh PA 15261, USA
| | - Edwin K. Jackson
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh PA 15261, USA
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21
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Di Iorio P, Beggiato S, Ronci M, Nedel CB, Tasca CI, Zuccarini M. Unfolding New Roles for Guanine-Based Purines and Their Metabolizing Enzymes in Cancer and Aging Disorders. Front Pharmacol 2021; 12:653549. [PMID: 33935764 PMCID: PMC8085521 DOI: 10.3389/fphar.2021.653549] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/12/2021] [Indexed: 12/22/2022] Open
Affiliation(s)
- P Di Iorio
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technologies (CAST), University of Chieti-Pescara, Chieti, Italy
| | - S Beggiato
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technologies (CAST), University of Chieti-Pescara, Chieti, Italy
| | - M Ronci
- Center for Advanced Studies and Technologies (CAST), University of Chieti-Pescara, Chieti, Italy.,Department of Pharmacy, University G. D'Annunzio Chieti, Chieti, Italy
| | - C B Nedel
- Laboratório de Biologia Celular de Gliomas, Programa de Pós-Graduação Em Biologia Celular e Do Desenvolvimento, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - C I Tasca
- Laboratório de Neuroquímica-4, Programa de Pós-Graduação Em Bioquímica, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - M Zuccarini
- Department of Medical, Oral and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technologies (CAST), University of Chieti-Pescara, Chieti, Italy
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