1
|
Lambiri DW, Levin LA. Maculopapillary Bundle Degeneration in Optic Neuropathies. Curr Neurol Neurosci Rep 2024; 24:203-218. [PMID: 38833037 DOI: 10.1007/s11910-024-01343-0] [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] [Accepted: 05/16/2024] [Indexed: 06/06/2024]
Abstract
PURPOSE OF REVIEW Degeneration of the maculopapillary bundle (MPB) is a prominent feature in a spectrum of optic neuropathies. MPB-selective degeneration is seen in specific conditions, such as nutritional and toxic optic neuropathies, Leber hereditary optic neuropathy (LHON), and dominant optic atrophy (DOA). Despite their distinct etiologies and clinical presentations, which encompass variations in age of incidence and monocular or binocular onset, these disorders share a core molecular mechanism: compromised mitochondrial homeostasis. This disruption is characterized by dysfunctions in mitochondrial metabolism, biogenesis, and protein synthesis. This article provides a comprehensive understanding of the MPB's role in optic neuropathies, emphasizing the importance of mitochondrial mechanisms in the pathogenesis of these conditions. RECENT FINDINGS Optical coherence tomography studies have characterized the retinal nerve fiber layer changes accompanying mitochondrial-affiliated optic neuropathies. Selective thinning of the temporal optic nerve head is preceded by thickening in early stages of these disorders which correlates with reductions in macular ganglion cell layer thinning and vascular atrophy. A recently proposed mechanism underpinning the selective atrophy of the MPB involves the positive feedback of reactive oxygen species generation as a common consequence of mitochondrial dysfunction. Additionally, new research has revealed that the MPB can undergo degeneration in the early stages of glaucoma, challenging the historically held belief that this area was not involved in this common optic neuropathy. A variety of anatomical risk factors influence the propensity of glaucomatous MPB degeneration, and cases present distinct patterns of ganglion cell degeneration that are distinct from those observed in mitochondria-associated diseases. This review synthesizes clinical and molecular research on primary MPB disorders, highlighting the commonalities and differences in their pathogenesis. KEY POINTS (BOX) 1. Temporal degeneration of optic nerve fibers accompanied by cecocentral scotoma is a hallmark of maculopapillary bundle (MPB) degeneration. 2. Mechanisms of MPB degeneration commonly implicate mitochondrial dysfunction. 3. Recent research challenges the traditional belief that the MPB is uninvolved in glaucoma by showing degeneration in the early stages of this common optic neuropathy, yet with features distinct from other MPB-selective neuropathies. 4. Reactive oxygen species generation is a mechanism linking mitochondrial mechanisms of MPB-selective optic neuropathies, but in-vivo and in-vitro studies are needed to validate this hypothesis.
Collapse
Affiliation(s)
- Darius W Lambiri
- Faculty of Medicine and Health Sciences, McGill University, Montreal, Canada
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada
| | - Leonard A Levin
- Faculty of Medicine and Health Sciences, McGill University, Montreal, Canada.
- Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Canada.
- Department of Neurology & Neurosurgery, McGill University, Montreal, Canada.
| |
Collapse
|
2
|
Buonfiglio F, Böhm EW, Pfeiffer N, Gericke A. Oxidative Stress: A Suitable Therapeutic Target for Optic Nerve Diseases? Antioxidants (Basel) 2023; 12:1465. [PMID: 37508003 PMCID: PMC10376185 DOI: 10.3390/antiox12071465] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Optic nerve disorders encompass a wide spectrum of conditions characterized by the loss of retinal ganglion cells (RGCs) and subsequent degeneration of the optic nerve. The etiology of these disorders can vary significantly, but emerging research highlights the crucial role of oxidative stress, an imbalance in the redox status characterized by an excess of reactive oxygen species (ROS), in driving cell death through apoptosis, autophagy, and inflammation. This review provides an overview of ROS-related processes underlying four extensively studied optic nerve diseases: glaucoma, Leber's hereditary optic neuropathy (LHON), anterior ischemic optic neuropathy (AION), and optic neuritis (ON). Furthermore, we present preclinical findings on antioxidants, with the objective of evaluating the potential therapeutic benefits of targeting oxidative stress in the treatment of optic neuropathies.
Collapse
Affiliation(s)
- Francesco Buonfiglio
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany; (E.W.B.); (N.P.)
| | | | | | - Adrian Gericke
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany; (E.W.B.); (N.P.)
| |
Collapse
|
3
|
Oxidative Stress in Antibiotic Toxic Optic Neuropathy Mimicking Acute LHON in a Patient with Exacerbation of Cystic Fibrosis. STRESSES 2023. [DOI: 10.3390/stresses3010028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Abstract
The striking similarity of disc edema without leakage on fluorescein angiography, which is pathognomonic of Leber hereditary optic neuropathy (LHON), was present in a patient with cystic fibrosis with antibiotic toxic optic neuropathy. This similarity suggested the common effect of oxidative stress on retinal ganglion cells in inherited mitochondrial and antibiotic optic neuropathies. We present the case of a patient with advanced cystic fibrosis on chronic antibiotic treatment who experienced a rapid painless bilateral visual decline over a course of a few weeks. At examination, his corrected visual acuity was reduced to 0.3 in both eyes, with dyschromatopsia and central scotoma. The appearance of the fundus resembled the typical clinical features of acute LHON with hyperemic optic discs and tortuous vessels with no dye leakage from the optic discs on fluorescein angiography. Ganglion cell layer loss was seen on optic coherence tomography, with all findings pointing to LHON. Genetic testing did not reveal any LHON-specific mutations. After extended genetic testing, a heterozygous variant c.209C>T in the OPA3 gene on chromosome 19, g.46032648G>A, classified as a variant of unknown significance, was also found. After discontinuing antibiotics and general improvements in his health, surprisingly, his visual function completely improved. Later, he also received a bilateral lung transplant that further improved his general condition, and his vision remained normal. Excluding LHON, the transient optic neuropathy in our patient could be mainly due to antibiotic toxicity of linezolid and ciprofloxacin, which have been linked to mitochondrial dysfunction and advanced cystic fibrosis with hypoxic status. We suggest the possibility that patients with cystic fibrosis may be more prone to developing mitochondrial optic neuropathy, especially with additional risk factors such as chronic antibiotic therapy, which affect mitochondrial function, and can perhaps serve as a model for LHON.
Collapse
|
4
|
Peterson E, Hawy E. Delayed and reversible ethambutol optic neuropathy. Am J Ophthalmol Case Rep 2022; 27:101611. [PMID: 35756837 PMCID: PMC9218146 DOI: 10.1016/j.ajoc.2022.101611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/20/2022] [Accepted: 05/26/2022] [Indexed: 11/26/2022] Open
Abstract
Purpose To document an unusual example of ethambutol optic neuropathy developing three years from treatment start date in the absence of renal dysfunction. Observations The patient, an 82-year-old, 61-kg male undergoing treatment for Mycobacterium Avium Complex, presented with visual acuity that was significantly worse than baseline three years after beginning a treatment regimen which included ethambutol at <15 mg/kg/day. He was also found to have central and paracentral scotomas in both eyes. Ethambutol treatment was immediately halted, and the patient's visual acuity and visual fields improved in the months following. Conclusions and Importance It is important to have a high index of suspicion for ethambutol toxicity in any patient on this drug who presents with vision changes consistent with optic neuropathy. The development of ethambutol optic neuropathy can be delayed, and vision loss may be reversible and can continue to improve over months after cessation of therapy.
Collapse
|
5
|
Zhang J, Liu Z, Song S, Fang J, Wang L, Zhao L, Li C, Li W, Byun HM, Guo L, Li P. The exposure levels and health risk assessment of antibiotics in urine and its association with platelet mitochondrial DNA methylation in adults from Tianjin, China: A preliminary study. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 231:113204. [PMID: 35065505 DOI: 10.1016/j.ecoenv.2022.113204] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
There has been extensive research on antibiotics exposure in adults by biomonitoring, but the biological mechanisms and potential risks to human health remain limited. In this study, 102 adults aged 26-44 years in Tianjin were studied and 23 common antibiotics in urine were analyzed by Liquid chromatography-mass spectrometry (LC-MS). All antibiotics were detected in urine, with an overall detection frequency of 40.4% (the detection frequencies of phenothiazines, quinolones, sulfonamides, tetracyclines, and chloramphenicol were 77%, 54%, 24%, 28%, and 49%, respectively.). Ofloxacin and enrofloxacin had the highest detection frequencies (85% and 81%), with median concentrations of 0.26 (IQR: 0.05-1.36) and 0.09 (IQR: 0.03-0.14) ng/mL, respectively. Based on health risk assessment, the predicted estimated daily exposures (EDEs) ranged from 0 μg/kg/day to 13.98 μg/kg/day. The hazard quotient (HQ) values of all the antibiotics except ofloxacin and ciprofloxacin were bellow one, which are considered safe. For all blood samples, the mitochondrial DNA (mtDNA) methylation levels in the MT-ATP6 (ranging between 3.86% and 34.18%) were slightly higher than MT-ATP8 and MT-ND5 (ranging between 0.57% and 9.32%, 1.08% and 19.62%, respectively). Furthermore, mtDNA methylation from MT-ATP6, MT-ATP8 and MT-ND5 were measured by bisulfite-PCR pyrosequencing. The association (P < 0.05) was found between mtDNA methylation level (MT-ATP8 and MT-ND5) and individual antibiotics including chlorpromazine, ciprofloxacin, enrofloxacin, norfloxacin, pefloxacin, sulfaquinoxaline, sulfachloropyridazine, chloramphenicol, and thiamphenicol, indicating that persistent exposure to low-dose multiple antibiotics may affect the mtDNA methylation level and in turn pose health risks.
Collapse
Affiliation(s)
- Jing Zhang
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China; Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, Tianjin 300384, China
| | - Ziquan Liu
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin 300072, China; Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin 300072, China; Wenzhou Safety (Emergency) Institute, Tianjin University, 325000, Wenzhou, China
| | - Shanjun Song
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China; National Institute of Metrology, Beijing 100029, China
| | - Junkai Fang
- Tianjin Institute of Medical & Pharmaceutical Sciences, Tianjin 300070, China
| | - Lei Wang
- Hebei Research Center for Geoanalysis, Hebei 071000, China
| | - Lei Zhao
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin 300072, China; Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin 300072, China; Wenzhou Safety (Emergency) Institute, Tianjin University, 325000, Wenzhou, China
| | - Chenguang Li
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China; Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, Tianjin 300384, China
| | - Weixia Li
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China; Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, Tianjin 300384, China
| | - Hyang-Min Byun
- Population Health Science Institute, Newcastle University, Campus for Ageing and Vitality, Newcastle Upon Tyne NE4 5PL, UK
| | - Liqiong Guo
- Institute of Disaster and Emergency Medicine, Tianjin University, Tianjin 300072, China; Tianjin Key Laboratory of Disaster Medicine Technology, Tianjin 300072, China; Wenzhou Safety (Emergency) Institute, Tianjin University, 325000, Wenzhou, China.
| | - Penghui Li
- School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China; Tianjin Key Laboratory of Hazardous Waste Safety Disposal and Recycling Technology, Tianjin 300384, China.
| |
Collapse
|
6
|
Zhang L, He J, Bai L, Ruan S, Yang T, Luo Y. Ribosome-targeting antibacterial agents: Advances, challenges, and opportunities. Med Res Rev 2021; 41:1855-1889. [PMID: 33501747 DOI: 10.1002/med.21780] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/08/2020] [Accepted: 12/19/2020] [Indexed: 02/05/2023]
Abstract
Ribosomes, which synthesize proteins, are critical organelles for the survival and growth of bacteria. About 60% of approved antibiotics discovered so far combat pathogenic bacteria by targeting ribosomes. However, several issues, such as drug resistance and toxicity, have impeded the clinical use of ribosome-targeting antibiotics. Moreover, the complexity of the bacteria ribosome structure has retarded the discovery of new ribosome-targeting agents that are considered as the key to the drug-resistance and toxicity. To deal with these challenges, efforts such as medicinal chemistry optimization, combination treatment, and new drug delivery system have been developed. But not enough, the development of structural biology and new screening methods bring powerful tools, such as cryo-electron microscopy technology, advanced computer-aided drug design, and cell-free in vitro transcription/translation systems, for the discovery of novel ribosome-targeting antibiotics. Thus, in this paper, we overview the research on different aspects of bacterial ribosomes, especially focus on discussing the challenges in the discovery of ribosome-targeting antibacterial drugs and advances made to address issues such as drug-resistance and selectivity, which, we believe, provide perspectives for the discovery of novel antibiotics.
Collapse
Affiliation(s)
- Laiying Zhang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China
| | - Jun He
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China
| | - Lang Bai
- Center of Infectious Diseases, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University and Collaborative Innovation Center, Chengdu, Sichuan, China
| | - Shihua Ruan
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China
| | - Tao Yang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China.,Laboratory of Human Diseases and Immunotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China.,Institute of Immunology and Inflammation, Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China
| | - Youfu Luo
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan, China
| |
Collapse
|
7
|
Xiao D, Jie Z, Ma Z, Ying Y, Guo X, Wen Y, Yang H. Fabrication of homogeneous waffle-like silver composite substrate for Raman determination of trace chloramphenicol. Mikrochim Acta 2020; 187:593. [PMID: 33026513 DOI: 10.1007/s00604-020-04567-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 09/25/2020] [Indexed: 11/25/2022]
Abstract
Waffle-like anodized aluminum oxide homogeneously immobilized with Ag nanoparticles (AAO/Ag) is rationally designed and fabricated as surface-enhanced Raman scattering (SERS) substrate. The as-prepared SERS substrate is characterized with transmission electron microscope (TEM), scanning electron microscopy (SEM), UV-Vis spectrophotometer, and Fourier transform infrared spectrometer (FT-IR). The AAO/Ag substrate shows good uniformity of the Raman signals (RSD = 7.02%) due to waffle-like AAO supporting the well-dispersed Ag nanoparticles. For real application, the AAO/Ag substrate is used for rapid determination of chloramphenicol (CAP) in honey with low detection limit (4.0 × 10-9 mol L-1) and good linearity from 1.0 × 10-5 to 1.0 × 10-8 mol L-1 based on the SERS peak at 1348 cm-1. The better accumulation in the short pore path of AAO improves the target molecule approaching into the vicinity of hot spots of Ag nanoparticles. The high selectivity for CAP is attributed to the strong interaction between -NO2 group in CAP and the composite substrate. Schematic representation of the preparation of SERS substrate, AAO150/Ag10-5 composite nanoparticles, and antibiotic determination.
Collapse
Affiliation(s)
- Dongfang Xiao
- Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, 100 Guilin Road, Shanghai, 200234, People's Republic of China
| | - Zhishun Jie
- Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, 100 Guilin Road, Shanghai, 200234, People's Republic of China
| | - Zhiyuan Ma
- Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, 100 Guilin Road, Shanghai, 200234, People's Republic of China
| | - Ye Ying
- Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, 100 Guilin Road, Shanghai, 200234, People's Republic of China.
| | - Xiaoyu Guo
- Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, 100 Guilin Road, Shanghai, 200234, People's Republic of China
| | - Ying Wen
- Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, 100 Guilin Road, Shanghai, 200234, People's Republic of China
| | - Haifeng Yang
- Department of Chemistry, Key Laboratory of Resource Chemistry of Ministry of Education, 100 Guilin Road, Shanghai, 200234, People's Republic of China.
| |
Collapse
|
8
|
Abstract
PURPOSE OF REVIEW The diagnosis of visual loss from toxic-metabolic and hereditary optic neuropathies may be delayed in some cases because of a failure to elicit important information in the clinical history or to recognize typical examination findings. An understanding of the features specific to each type of toxic-metabolic and hereditary optic neuropathy, and of the underlying mechanism of insult to the optic nerve, could lead to earlier recognition, diagnosis, and treatment (when available). RECENT FINDINGS Understanding of the role of mitochondria in toxic-metabolic and hereditary optic neuropathies is growing, particularly regarding the mechanism of insult of certain agents (medications and toxins) and of vitamin B12 deficiency. New developments in the quest for treatment for hereditary optic neuropathy, specifically Leber hereditary optic neuropathy, are being seen. SUMMARY Toxic-metabolic and hereditary optic neuropathies present in a similar fashion, with painless, progressive, bilateral visual loss with dyschromatopsia and cecocentral visual field defects. The associated retinal ganglion cell and axonal loss is typically due to mitochondrial dysfunction caused by an exogenous agent (toxic), by insufficient or deficient substrate (metabolic or nutritional), or by abnormal proteins or mitochondrial structure determined by a genetic mutation (hereditary).
Collapse
|