The circRNA circ-Nbea participates in regulating diabetic encephalopathy

CircRNA expression profiles and regulatory networks in the vitreous humor of people with high myopia

Myopia is a global health and economic issue. Circular RNAs (circRNAs) have been shown to play an important role in the pathogenesis of many ocular diseases. We first evaluated the circRNA profiles and possible roles in vitreous humor samples of individuals with high myopia by a competitive endogenous RNA (ceRNA) array. Vitreous humor samples were collected from 15 high myopic (5 for ceRNA array, and 10 for qPCR) and 15 control eyes (5 for ceRNA array, and 10 for qPCR) with idiopathic epiretinal membrane (ERM) and macular hole (MH). 486 circRNAs (339 upregulated and 147 downregulated) and 264 mRNAs (202 upregulated and 62 downregulated) were differentially expressed between the high myopia and control groups. The expression of hsa_circ_0033079 (hsa-circDicer1), hsa_circ_0029989 (hsa-circNbea), hsa_circ_0019072 (hsa-circPank1) and hsa_circ_0089716 (hsa-circEhmt1) were validated by qPCR. Pearson analysis and multivariate regression analysis showed positive and significant correlations for axial length with hsa-circNbea and hsa-circPank1. KEGG analysis showed that the target genes of circRNAs were enriched in the mTOR, insulin, cAMP, and VEGF signaling pathways. GO analysis indicated that circRNAs mainly targeted transcription, cytoplasm, and protein binding. CircRNA-associated ceRNA network analysis and PPI network analysis identified several critical genes for myopia. The expression of circNbea, circPank1, miR-145-5p, miR-204-5p, Nras, Itpr1 were validated by qPCR in the sclera of form-deprivation myopia (FDM) mice model. CircPank1/miR-145-5p/NRAS and circNbea/miR-204-5p/ITPR1 were identified and may be important in the progression of myopia. Our findings suggest that circRNAs may contribute to the pathogenesis of myopia and may serve as potential biomarkers.

Metabolic memory: mechanisms and diseases

Metabolic diseases and their complications impose health and economic burdens worldwide. Evidence from past experimental studies and clinical trials suggests our body may have the ability to remember the past metabolic environment, such as hyperglycemia or hyperlipidemia, thus leading to chronic inflammatory disorders and other diseases even after the elimination of these metabolic environments. The long-term effects of that aberrant metabolism on the body have been summarized as metabolic memory and are found to assume a crucial role in states of health and disease. Multiple molecular mechanisms collectively participate in metabolic memory management, resulting in different cellular alterations as well as tissue and organ dysfunctions, culminating in disease progression and even affecting offspring. The elucidation and expansion of the concept of metabolic memory provides more comprehensive insight into pathogenic mechanisms underlying metabolic diseases and complications and promises to be a new target in disease detection and management. Here, we retrace the history of relevant research on metabolic memory and summarize its salient characteristics. We provide a detailed discussion of the mechanisms by which metabolic memory may be involved in disease development at molecular, cellular, and organ levels, with emphasis on the impact of epigenetic modulations. Finally, we present some of the pivotal findings arguing in favor of targeting metabolic memory to develop therapeutic strategies for metabolic diseases and provide the latest reflections on the consequences of metabolic memory as well as their implications for human health and diseases.

Exploring the Multifaceted Biologically Relevant Roles of circRNAs: From Regulation, Translation to Biomarkers

CircRNAs are a category of regulatory RNAs that have garnered significant attention in the field of regulatory RNA research due to their structural stability and tissue-specific expression. Their circular configuration, formed via back-splicing, results in a covalently closed structure that exhibits greater resistance to exonucleases compared to linear RNAs. The distinctive regulation of circRNAs is closely associated with several physiological processes, as well as the advancement of pathophysiological processes in several human diseases. Despite a good understanding of the biogenesis of circular RNA, details of their biological roles are still being explored. With the steady rise in the number of investigations being carried out regarding the involvement of circRNAs in various regulatory pathways, understanding the biological and clinical relevance of circRNA-mediated regulation has become challenging. Given the vast landscape of circRNA research in the development of the heart and vasculature, we evaluated cardiovascular system research as a model to critically review the state-of-the-art understanding of the biologically relevant functions of circRNAs. We conclude the review with a discussion of the limitations of current functional studies and provide potential solutions by which these limitations can be addressed to identify and validate the meaningful and impactful functions of circRNAs in different physiological processes and diseases.

A systematic review of preclinical studies exploring the role of insulin signalling in executive function and memory

Beside its involvement in somatic dysfunctions, altered insulin signalling constitutes a risk factor for the development of mental disorders like Alzheimer's disease and obsessive-compulsive disorder. While insulin-related somatic and mental disorders are often comorbid, the fundamental mechanisms underlying this association are still elusive. Studies conducted in rodent models appear well suited to help decipher these mechanisms. Specifically, these models are apt to prospective studies in which causative mechanisms can be manipulated via multiple tools (e.g., genetically engineered models and environmental interventions), and experimentally dissociated to control for potential confounding factors. Here, we provide a narrative synthesis of preclinical studies investigating the association between hyperglycaemia - as a proxy of insulin-related metabolic dysfunctions - and impairments in working and spatial memory, and attention. Ultimately, this review will advance our knowledge on the role of glucose metabolism in the comorbidity between somatic and mental illnesses.

Decrypting the circular RNAs does a favor for us: Understanding, diagnosing and treating diabetes mellitus and its complications

Circular RNAs (circRNAs), a novel type of single-stranded noncoding RNAs with a covalently closed loop structure, are generated in a circular conformation via non-canonical splicing or back-splicing events. Functionally, circRNAs have been elucidated to soak up microRNAs (miRNAs) and RNA binding proteins (RBPs), serve as protein scaffolds, maintain mRNA stability, and regulate gene transcription and translation. Notably, circRNAs are strongly implicated in the regulation of β-cell functions, insulin resistance, adipocyte functions, inflammation as well as oxidative stress via acting as miRNA sponges and RBP sponges. Basic and clinical studies have demonstrated that aberrant alterations of circRNAs expressions are strongly associated with the initiation and progression of diabetes mellitus (DM) and its complications. Here in this review, we present a summary of the biogenesis, transportation, degradation and functions of circRNAs, and highlight the recent findings on circRNAs and their action mechanisms in DM and its complications. Overall, this review should contribute greatly to our understanding of circRNAs in DM pathogenesis, offering insights into the further perspectives of circRNAs for DM diagnosis and therapy.

Caffeic acid attenuates neuroinflammation and cognitive impairment in streptozotocin-induced diabetic rats: Pivotal role of the cholinergic and purinergic signaling pathways

The present study evaluated the effect of caffeic acid (CA) on behavioral learning and memory tasks in the diabetic state. We also evaluated the effect of this phenolic acid on the enzymatic activities of acetylcholinesterase, ecto-nucleoside triphosphate diphosphohydrolase, ecto-5-nucleotidase and adenosine deaminase as well as on the density of M1R, α7nAChR, P2×7R, A1R, A2AR, and inflammatory parameters in the cortex and hippocampus of diabetic rats. Diabetes was induced by a single intraperitoneal dose of streptozotocin (55 mg/kg). The animals were divided into six groups: control/vehicle; control/CA 10 and 50 mg/kg; diabetic/vehicle; diabetic/CA 10 and 50 mg/kg, treated by gavage. The results showed that CA improved learning and memory deficits in diabetic rats. Also, CA reversed the increase in acetylcholinesterase and adenosine deaminase activities and reduced ATP and ADP hydrolysis. Moreover, CA increased the density of M1R, α7nAChR, and A1R receptors and reversed the increase in P2×7R and A2AR density in both evaluated structures. In addition, CA treatment attenuated the increase in NLRP3, caspase 1, and interleukin 1β density in the diabetic state; moreover, it increased the density of interleukin-10 in the diabetic/CA 10 mg/kg group. The results indicated that CA treatment positively modified the activities of cholinergic and purinergic enzymes and the density of receptors, and improved the inflammatory parameters of diabetic animals. Thus, the outcomes suggest that this phenolic acid could improve the cognitive deficit linked to cholinergic and purinergic signaling in the diabetic state.

Identification and characterization of differentially expressed circRNA in 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced cleft palate

Various circular RNAs (circRNAs) are novel class of non-coding RNAs, which are pervasively transcribed in the genome. CircRNAs play important roles in human, animals and plants. Up to now, there was no report regarding circRNAs of cleft palate by 2,3,7,8-tetrachlorodibenzo-pdioxin (TCDD) induce. The present study screened identification and characterization of differential expressed-circRNAs in TCDD-induced cleft palate. 6903 circRNAs candidates came from cleft palates. Among them, 3525 circRNAs are up-regulation, and 3378 circRNAs are down-regulation by TCDD induce. The cluster and GO analysis found that circRNAs involved in biological process, cellular component, and molecular function. Through the analysis of KEGG Pathway, circRNAs made functions via classical signaling pathway in cleft palate, such as TGF-beta signaling pathway, BMP signal pathway, MAPK signaling pathway. In addition, we found down-regulated circRNA224, circRNA3302 and up-regulated circRNA5021 targeted tgfbr3, but up-regulated circRNA4451 targeted tgfbr2. circRNA4451 may make functions through TGF-beta signaling pathway. These results suggested that many different circRNAs may make important role in TCDD-induced cleft palate, which provided a theoretical basis for further research.