Review
Biochemistry & Molecular Biology
Yan-Jun Zong, Xiao-Zhou Liu, Lei Tu, Yu Sun
Summary: This review discusses the contribution of the connexin gene family to hearing loss, focusing on the GJB2, GJB6, and GJA1 genes. Mutations in these genes can lead to comprehensive or non-comprehensive genetic deafness in newborns. The precise regulation of connexin biosynthesis, structural composition, and degradation is crucial for proper functioning of gap junctions. This review provides insights into the etiological principles of connexin mutations and offers potential therapeutic strategies for hereditary deafness.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Audiology & Speech-Language Pathology
Jean Defourny, Marc Thiry
Summary: Cx26 and Cx30 assemble into heteromeric gap junctions in the cochlea, facilitating K+ removal from sensory hair cells. A new study reveals tricellular adherens junctions play a critical role in connexin trafficking and membrane channel assembly.
Article
Cell Biology
Remi Fournel, Espen Hartveit, Margaret Lin Veruki
Summary: Gap junctions between cone bipolar cells in the retina may not be strong enough to mediate effective electrical coupling, as shown by whole-cell voltage-clamp recordings in rat retinal slices. The study suggests that these junctions may play a role in chemical and/or metabolic coupling instead.
CELLULAR AND MOLECULAR NEUROBIOLOGY
(2021)
Article
Oncology
Ke Gong, Qingqi Hong, Huiwen Wu, Fen Wang, Linhai Zhong, Lingjia Shen, Piao Xu, Wenqing Zhang, Hanwei Cao, Yan-yan Zhan, Tianhui Hu, Xiaoting Hong
Summary: In vivo tumor growth is characterized by a necrotic core generated by oxygen and nutrients gradients, which can also be observed in in vitro three-dimensional tumor spheroids. Gap junctions play a critical role in cancer development, and this study found that the connexin 43 (Cx43) protein reduces the area of necrotic core in colon cancer 3D spheroids, promoting tumor growth advantage. This effect is dependent on gap junction channel functions, and the enhanced glucose uptake and altered signaling pathways contribute to the increased ATP content and oxygen consumption rate. The study also revealed a heterogeneous expression pattern of Cx43 in colon cancer compared to normal tissue, and higher levels of Cx43 are associated with worse clinical outcomes. These findings suggest a novel role of connexin in tumor growth and provide insights into the metabolic needs of solid tumors.
Article
Ophthalmology
Ricardo Usategui-Martin, Kevin Puertas-Neyra, Nadia Galindo-Cabello, Leticia A. Hernandez-Rodriguez, Fernando Gonzalez-Perez, Jose Carlos Rodriguez-Cabello, Rogelio Gonzalez-Sarmiento, Jose Carlos Pastor, Ivan Fernandez-Bueno
Summary: This study evaluated the neuroprotective capability of the secretome of human bone marrow MSCs and found that it can slow retinal neurodegeneration by activating antioxidant machinery, modulating autophagy, and inhibiting apoptosis and necroptosis. The secretome of bmMSCs may be a potential therapeutic option for treating retinal neurodegenerative diseases.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2022)
Review
Biochemistry & Molecular Biology
Selma Cetin-Ferra, Sharon C. Francis, Anthonya T. Cooper, Kit Neikirk, Andrea G. Marshall, Antentor Hinton Jr, Sandra A. A. Murray
Summary: Mitochondria contain connexins that form gap junction channels, playing a role in cell-cell communication. However, connexins in mitochondria have also been found to assemble into hemichannels and may be involved in regulating mitochondrial functions such as potassium fluxes and respiration. However, the presence and function of mitochondrial connexins are still poorly understood. Understanding the significance of mitochondrial connexins and their contact sites is crucial for developing therapeutic interventions in mitochondria-related diseases.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Cell Biology
Nicole M. Novielli-Kuntz, Eric R. Press, Kevin Barr, Marco A. M. Prado, Dale W. Laird
Summary: Studies on mice carrying the human disease-associated A88V Cx30 mutation revealed major morphological changes in the brain, particularly in aging mice. These changes had a more pronounced consequence for cognitive function in female mice, likely linked to the dysregulation of both Cx30 and Cx43 levels in the brain.
DISEASE MODELS & MECHANISMS
(2021)
Article
Oncology
Birte Schulz, Valerie Schumacher, Anaclet Ngezahayo, Daniela Maier-Begandt, Nadine Schadzek, Jochen Wilhelm, Wolfgang Weidner, Adrian Pilatz, Daniela Fietz, Sabine Kliesch, Nadine Schnepel, Nina Hambruch, Kristina Rode, Marion Langeheine, Ralph Brehm
Summary: In this study, a cell culture model consisting of human FS1 Sertoli cells and human TCam-2 seminoma-like cells was used to investigate the role of junctional proteins in seminoma progression. The results showed that Cx43, Cx45, and N-cadherin were expressed in both cell lines at mRNA and/or protein level, confirming their representativeness for Sertoli and seminoma cells.
Article
Biology
Ji Xu, Bruce J. Nicholson
Summary: This study investigated the characteristics of Cx30 hemichannels using heterologous expression systems. It was found that Cx30 hemichannels are sensitive to voltage and extracellular Ca2+ and show minimal selectivity for small ions but increased permeability for larger anions. Comparison with Cx26 gap junctions in the cochlea revealed differences in ATP permeability, indicating distinct physiological functions of Cx30 and Cx26 in energy distribution.
Review
Biochemistry & Molecular Biology
Kajetan Kielbowski, Estera Bakinowska, Andrzej Pawlik
Summary: Connexins are involved in intercellular communication through hemichannels and gap junctions, playing a crucial role in regulating cell homeostasis, proliferation, and differentiation. Changes in Cx distribution, degradation, and post-translational modifications have been linked to cancer, cardiovascular, and neurological diseases. Depending on the isoform, Cx can either promote or suppress the development of atherosclerosis by affecting endothelial dysfunction, monocyte recruitment, vascular smooth muscle cell activation, or autophagy inhibition. Inhibition or modulation of specific Cx isoforms could potentially serve as therapeutic targets in atherosclerosis.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Cell Biology
Xiwen Ling, Siyuan Peng, Yaqin Xu, Fujiang Chu
Summary: This study found that simvastatin regulates gap junction function in vascular endothelial cells by upregulating Cx37 and Cx40 expression and downregulating Cx43 expression.
ANIMAL CELLS AND SYSTEMS
(2022)
Review
Biochemistry & Molecular Biology
Tamas Kovacs-Oller, Gergely Szarka, Gyula Hoffmann, Loretta Pentek, Greta Valentin, Liliana Ross, Bela Volgyi
Summary: Gap junctions and connexin proteins undergo major changes in degenerating retinal tissue. It is important to distinguish these adaptive changes from alterations following tissue deterioration.
Article
Multidisciplinary Sciences
Yuting Li, Zhen Li, Yumeng Quan, Hongyun Cheng, Manuel A. Riquelme, Xiao-Dong Li, Sumin Gu, Jean X. Jiang
Summary: The study provides evidence for the involvement of macrophages in repairing lens capsule rupture, with CSF-1 accelerating the repair process and inhibition of the CSF-1 receptor delaying repair. This suggests that M2 macrophages activated by CSF-1 play a crucial role in mediating capsule rupture repair and fibrosis development.
Review
Biochemistry & Molecular Biology
Gustavo Bernardes Fanaro, Marcelo Rodrigues Marques, Karin da Costa Calaza, Rafael Brito, Andre Moreira Pessoni, Henrique Rocha Mendonca, Deborah Emanuelle de Albuquerque Lemos, Jose Luiz de Brito Alves, Evandro Leite de Souza, Marinaldo Pacifico Cavalcanti Neto
Summary: Diabetic retinopathy is a neurodegenerative and vascular disease that can lead to blindness and is caused by complications of diabetes mellitus. Current therapies are limited in their effectiveness, and there is a need for more effective alternative treatments to target glycemic, vascular, and neuronal parameters, as well as cellular damage from inflammation and oxidative stress. Dietary polyphenols have shown potential in reducing oxidative and inflammatory markers in various diseases, including metabolic and neurodegenerative diseases. However, more data from human studies is needed to determine the therapeutic potential of these compounds. This review aims to provide a comprehensive understanding of the effects of dietary phenolic compounds on the pathophysiology of diabetic retinopathy, particularly in relation to oxidative and inflammatory mechanisms, using evidence from experimental studies.
Article
Immunology
Rui Dong, Yuqiang Han, Linhao Jiang, Shuai Liu, Fujun Zhang, Liangyu Peng, Zimo Wang, Zhengliang Ma, Tianjiao Xia, Xiaoping Gu
Summary: This study reveals a novel mechanism of the GJ-Cx43-mediated astrocytic network involved in isoflurane-induced neuroinflammation and cognitive impairments, which provides new mechanistic insight into the pathogenesis of POCD and identifies potential targets for its treatment.
JOURNAL OF NEUROINFLAMMATION
(2022)
Article
Cell Biology
Seema Banerjee, Qin Wang, Chung Him So, Feng Pan
Article
Biochemistry & Molecular Biology
Tamas Kovacs-Oller, Elena Ivanova, Gergely Szarka, Adam J. Tengolics, Bela Volgyi, Botir T. Sagdullaev
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2020)
Article
Neurosciences
Seema Banerjee, Qin Wang, Fuxin Zhao, George Tang, Chunghim So, Dennis Tse, Chi-Ho To, Yun Feng, Xiangtian Zhou, Feng Pan
FRONTIERS IN CELLULAR NEUROSCIENCE
(2020)
Article
Cell Biology
Tamas Kovacs-Oller, Gergely Szarka, Adam J. Tengolics, Alma Ganczer, Boglarka Balogh, Edina Szabo-Meleg, Miklos Nyitrai, Bela Voelgyi
Article
Biochemistry & Molecular Biology
Qin Wang, Seema Banerjee, Chunghim So, Chunting Qiu, Hang-I Christie Lam, Dennis Tse, Bela Volgyi, Feng Pan
Article
Neurosciences
Qin Wang, Seema Banerjee, ChungHim So, ChunTing Qiu, YingHon Sze, Thomas Chuen Lam, Chi-Ho To, Feng Pan
Summary: Low-dose atropine has been shown to effectively control myopia progression with minimal side effects. However, the impact of atropine on retinal ganglion cells (RGCs) remains unclear. Direct application of atropine on the retina affected the light-evoked responses of ON and OFF alpha RGCs in a dose- and time-dependent manner, but lower concentrations did not disrupt synchronized firing patterns between RGCs.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2021)
Article
Biochemistry & Molecular Biology
Samuel Abokyi, Sze-Wan Shan, Christie Hang- Lam, Kirk Patrick Catral, Feng Pan, Henry Ho-Lung Chan, Chi-Ho To, Dennis Yan-Yin Tse
Summary: This study found that lysosomal dysfunction and autophagy defects underlie oxidative damage induced by HQ in human RPE cells, and supports lysosomal stabilization with the proteasome inhibitor MG132 as a potential remedy for oxidative damage in RPE and AMD.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Cell Biology
Katalin Fusz, Tamas Kovacs-Oller, Peter Kobor, Edina Szabo-Meleg, Bela Volgyi, Peter Buzas, Ildiko Telkes
Summary: The study found regional differences in the distribution of connexin-36 in the retinas of different species, which affects the processing of visual input. There is a close correlation between the density of Prox1-immunoreactive amacrine cells and the density of Cx36-immunoreactive plaques, which may contribute to functional ON/OFF asymmetries in the retina.
Article
Biochemistry & Molecular Biology
Boglarka Balogh, Gergely Szarka, Adam J. Tengolics, Gyula Hoffmann, Bela Volgyi, Tamas Kovacs-Oller
Summary: The study found that exposure to LED light increased levels of major apoptosis-related markers and activated microglial cells and Caspase-3, suggesting that overuse of unfiltered direct LED light can have detrimental effects on human retina.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Ophthalmology
Sandeep Kumar, Alexandra Benavente-Perez, Reynolds Ablordeppey, Carol Lin, Suresh Viswanathan, Abram Akopian, Stewart A. Bloomfield
Summary: A robust and reproducible model of glaucoma in the marmoset has been developed, demonstrating structural and functional alterations of the retina and optic nerve characteristic of glaucoma in humans and animal models.
TRANSLATIONAL VISION SCIENCE & TECHNOLOGY
(2022)
Article
Cell Biology
Alma Ganczer, Gergely Szarka, Marton Balogh, Gyula Hoffmann, Adam Jonatan Tengolics, Garrett Kenyon, Tamas Kovacs-Oller, Bela Volgyi
Summary: Retinal ganglion cells encrypt stimulus features of the visual scene in action potentials and convey them toward higher visual centers in the brain. Each subtype of RGC establishes a separate signaling route for a specific visual feature. The efficiency of encoding depends on several factors, and RGCs perform further analysis before generating the final output spike train. These specific kinetic features are essential for target postsynaptic neurons in the brain to effectively decode and interpret signals.
Editorial Material
Biochemistry & Molecular Biology
Tamas Kovacs-Oller, Bela Volgyi
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Review
Biochemistry & Molecular Biology
Tamas Kovacs-Oller, Gergely Szarka, Gyula Hoffmann, Loretta Pentek, Greta Valentin, Liliana Ross, Bela Volgyi
Summary: Gap junctions and connexin proteins undergo major changes in degenerating retinal tissue. It is important to distinguish these adaptive changes from alterations following tissue deterioration.
Article
Ophthalmology
Sandeep Kumar, Hariharasubramanian Ramakrishnan, Suresh Viswanathan, Abram Akopian, Stewart A. Bloomfield
Summary: The study revealed that damage to the inner retina in glaucoma leads to impairments in the outer retina. Protecting the inner retinal neurons can effectively prevent damage to the outer retina.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2021)
Article
Neurosciences
Seema Banerjee, Qing Wang, George Tang, ChungHim So, Sze Wan Shan, King Kit Li, Chi-Wai Do, Feng Pan
Summary: Our study demonstrated an increase in phosphorylation of connexin35 at Ser276 in both 12-hour and 7-day stages of lens-induced myopia in cone-dominant chicken retinas, potentially leading to increased coupling with AII amacrine cells.
VISUAL NEUROSCIENCE
(2021)