ABSTRACT
BACKGROUND:Connexin 43(Cx43),which is thought to be engaged in the gap junction process and build the structural groundwork for the development of direct material signaling channels between cells,is crucial for maintaining the homeostatic balance of tissue metabolism.Recent research,however,has revealed fresh information about its distinct hemichannel function and highlighted the significance of its subcellular localization and self-fragmentation for cellular physiological activities and pathological processes. OBJECTIVE:To systematically summarize the molecular characteristics and expression of Cx43 in a variety of cells,concentrate on the pathological and physiological roles of channel-dependent Cx43 and channel-independent Cx43,and investigate the potential value in disease treatment by reviewing the pertinent literature in the database. METHODS:The Chinese and English keywords were"gap junction,connexin 43(Cx43),hemichannel,channel-dependent Cx43,channel-independent Cx43,extracellular vesicles(EVs),mitochondria,GJA1-20k",which were searched in PubMed and CNKI.Finally,81 articles were selected for review. RESULTS AND CONCLUSION:(1)The canonical role of Cx43 is to form a gap junction channel.Channel-dependent Cx43 has primarily involved in disease physiopathological processes by directly constituting gap junction channels,but full attention should be paid to the issue of its structural and functional integrity.Adhesion is a crucial characteristic of gap junctions,which are strongly associated with barrier-like diseases.(2)The non-canonical role of Cx43 is non-gap junction channel-dependent effect.In addition to being localized at the plasma membrane,inner mitochondrial membrane,extracellular vesicle surface,and other structures,Cx43 hexamer has also been found to play a role in positive pro-inflammatory mechanisms,mitochondrial functional metabolism,and targeted uptake of extracellular vesicles in inflammatory diseases.Selective shortened segments control mitochondrial homeostasis by encouraging the polymerization of peri-mitochondrial actin and are involved in the targeted translocation of full-length Cx43 to intracellular structural domains.(3)The development of targeted medicines and the solving of issues like the mechanism of seed cell transformation in tissue engineering-based therapies are both made possible by these two categories of impacts.The interactions of various types of Cx43,however,are frequently not fully taken into account in some of the existing original studies,which confuses the overall characteristics and skews the results.(4)It is necessary to systematically frame the physiological characteristics of Cx43 in different forms and its potential mechanisms in various diseases,so as to provide a reference for the exploration of the Cx43 integrity mechanism and the diagnosis and treatment of multiple diseases.
ABSTRACT
Adipose tissue is a promising target for treating obesity and metabolic diseases. However, pharmacological agents usually fail to effectively engage adipocytes due to their extraordinarily large size and insufficient vascularization, especially in obese subjects. We have previously shown that during cold exposure, connexin43 (Cx43) gap junctions are induced and activated to connect neighboring adipocytes to share limited sympathetic neuronal input amongst multiple cells. We reason the same mechanism may be leveraged to improve the efficacy of various pharmacological agents that target adipose tissue. Using an adipose tissue-specific Cx43 overexpression mouse model, we demonstrate effectiveness in connecting adipocytes to augment metabolic efficacy of the β 3-adrenergic receptor agonist Mirabegron and FGF21. Additionally, combing those molecules with the Cx43 gap junction channel activator danegaptide shows a similar enhanced efficacy. In light of these findings, we propose a model in which connecting adipocytes via Cx43 gap junction channels primes adipose tissue to pharmacological agents designed to engage it. Thus, Cx43 gap junction activators hold great potential for combination with additional agents targeting adipose tissue.
ABSTRACT
Objective@#To explore the genetic basis of a pedigree affected with oculodentodigital dysplasia.@*Methods@#Genomic DNA was extracted from peripheral blood or amniotic fluid samples derived from the pedigree. Exon 2 of the GJA1 gene was amplified for sequencing.@*Results@#Two pedigree members were found to carry heterozygous missense variation of the GJA1 gene, c. 221A>C (p.H74P).@*Conclusion@#The missense c. 221A>C variation of the GJA1 gene probably underlies the oculodentodigital dysplasia in this pedigree.