Divergent regulation of lncRNA expression by ischemia in adult and aging mice

The role of lncRNAs in AKI and CKD: Molecular mechanisms, biomarkers, and potential therapeutic targets

Exosomes, a type of extracellular vesicle, are commonly found in different body fluids and are rich in nucleic acids (circRNA, lncRNAs, miRNAs, mRNAs, tRNAs, etc.), proteins, and lipids. They are involved in intercellular communication. lncRNAs are responsible for the modulation of gene expression, thus affecting the pathological process of kidney injury. This review summarizes the latest knowledge on the roles of exosome lncRNAs and circulating lncRNAs in the pathogenesis, biomarker discovery, and treatment of chronic kidney disease, renal fibrosis, and acute kidney injury, providing an overview of novel regulatory approaches and lncRNA delivery systems.

Targeted Drug Therapy for Senescent Cells Alleviates Unilateral Ureteral Obstruction-Induced Renal Injury in Rats

Hydronephrosis resulting from unilateral ureteral obstruction (UUO) is a common cause of renal injury, often progressing to late-stage renal fibrosis or even potential renal failure. Renal injury and repair processes are accompanied by changes in cellular senescence phenotypes. However, the mechanism is poorly understood. The purpose of this study is to clarify the changes in senescence phenotype at different time points in renal disease caused by UUO and to further investigate whether eliminating senescent cells using the anti-senescence drug ABT263 could attenuate UUO-induced renal disease. Specifically, renal tissues were collected from established UUO rat models on days 1, 2, 7, and 14. The extent of renal tissue injury and fibrosis in rats was assessed using histological examination, serum creatinine, and blood urea nitrogen levels. The apoptotic and proliferative capacities of renal tissues and phenotypic changes in cellular senescence were evaluated. After the intervention of the anti-senescence drug ABT263, the cellular senescence as well as tissue damage changes were re-assessed. We found that before the drug intervention, the UUO rats showed significantly declined renal function, accompanied by renal tubular injury, increased inflammatory response, and oxidative stress, alongside aggravated cellular senescence. Meanwhile, after the treatment with ABT263, the rats had a significantly lower number of senescent cells, attenuated renal tubular injury and apoptosis, enhanced proliferation, reduced oxidative stress and inflammation, improved renal function, and markedly inhibited fibrosis. This suggests that the use of the anti-senescence drug ABT263 to eliminate senescent cells can effectively attenuate UUO-induced renal injury. This highlights the critical role of cellular senescence in the transformation of acute injury into chronic fibrosis.

Cellular senescence in acute kidney injury: Target and opportunity

Acute kidney injury (AKI) is a common clinical disease with a high incidence and mortality rate. It typically arises from hemodynamic alterations, sepsis, contrast agents, and toxic drugs, instigating a series of events that culminate in tissue and renal damage. This sequence of processes often leads to acute renal impairment, prompting the initiation of a repair response. Cellular senescence is an irreversible arrest of the cell cycle. Studies have shown that renal cellular senescence is closely associated with AKI through several mechanisms, including the promotion of oxidative stress and inflammatory response, telomere shortening, and the down-regulation of klotho expression. Exploring the role of cellular senescence in AKI provides innovative therapeutic ideas for both the prevention and treatment of AKI. Furthermore, it has been observed that targeted removal of senescent cells in vivo can efficiently postpone senescence, resulting in an enhanced prognosis for diseases associated with senescence. This article explores the effects of common anti-senescence drugs senolytics and senostatic and lifestyle interventions on renal diseases, and mentions the rapid development of mesenchymal stem cells (MSCs). These studies have taken senescence-related research to a new level. Overall, this article comprehensively summarizes the studies on cellular senescence in AKI, aiming is to elucidate the relationship between cellular senescence and AKI, and explore treatment strategies to improve the prognosis of AKI.

Endothelial microRNAs and long noncoding RNAs in cardiovascular ageing

Atherosclerosis and numerous other cardiovascular diseases develop in an age-dependent manner. The endothelial cells that line the vessel walls play an important role in the development of atherosclerosis. Non-coding RNA like microRNAs and long non-coding RNAs are known to play an important role in endothelial function and are implicated in the disease progression. Here, we summarize several microRNAs and long non-coding RNAs that are known to have an altered expression with endothelial aging and discuss their role in endothelial cell function and senescence. These processes contribute to aging-induced atherosclerosis development and by targeting the non-coding RNAs controlling endothelial cell function and senescence, atherosclerosis can potentially be attenuated.

The role of endothelial TRP channels in age-related vascular cognitive impairment and dementia

Transient receptor potential (TRP) proteins are part of a superfamily of polymodal cation channels that can be activated by mechanical, physical, and chemical stimuli. In the vascular endothelium, TRP channels regulate two fundamental parameters: the membrane potential and the intracellular Ca²⁺ concentration [(Ca²⁺)_i]. TRP channels are widely expressed in the cerebrovascular endothelium, and are emerging as important mediators of several brain microvascular functions (e.g., neurovascular coupling, endothelial function, and blood-brain barrier permeability), which become impaired with aging. Aging is the most significant risk factor for vascular cognitive impairment (VCI), and the number of individuals affected by VCI is expected to exponentially increase in the coming decades. Yet, there are currently no preventative or therapeutic treatments available against the development and progression of VCI. In this review, we discuss the involvement of endothelial TRP channels in diverse physiological processes in the brain as well as in the pathogenesis of age-related VCI to explore future potential neuroprotective strategies.

Epigenetic control of LncRNA NEAT1 enables cardiac fibroblast pyroptosis and cardiac fibrosis

Cardiac fibroblasts (CFs) drive extracellular matrix remodeling after inflammatory injury, leading to cardiac fibrosis and diastolic dysfunction. Recent studies described the role of epigenetics in cardiac fibrosis. Nevertheless, detailed reports on epigenetics regulating CFs pyroptosis and describing their implication in cardiac fibrosis are still unclear. Here, we found that DNMT3A reduces the expression of lncRNA Neat1 and promotes the NLRP3 axis leading to CFs pyroptosis, using cultured cells, animal models, and clinical samples to shed light on the underlying mechanism. We report that pyroptosis-related genes are increased explicitly in cardiac fibrosis tissue and LPS-treated CFs, while lncRNA Neat1 decreased. Mechanistically, we show that loss of DNMT3A or overexpression of lncRNA Neat1 in CFs after LPS treatment significantly enhances CFs pyroptosis and the production of pyroptosis-related markers in vitro. It has been demonstrated that DNMT3A can decrease lncRNA Neat1, promoting NLRP3 axis activation in CFs treated with LPS. In sum, this study is the first to identify that DNMT3A methylation decreases the expression of lncRNA Neat1 and promotes CFs pyroptosis and cardiac fibrosis, suggesting that DNMT3A and NEAT1 may function as an anti-fibrotic therapy target in cardiac fibrosis.

Cellular senescence in ischemia/reperfusion injury

Ischemia/reperfusion (IR) injury, a main reason of mortality and morbidity worldwide, occurs in many organs and tissues. As a result of IR injury, senescent cells can accumulate in multiple organs. Increasing evidence shows that cellular senescence is the underlying mechanism that transforms an acute organ injury into a chronic one. Several recent studies suggest senescent cells can be targeted for the prevention or elimination of acute and chronic organ injury induced by IR. In this review, we concisely introduce the underlying mechanism and the pivotal role of premature senescence in the transition from acute to chronic IR injuries. Special focus is laid on recent advances in the mechanisms as well as on the basic and clinical research, targeting cellular senescence in multi-organ IR injuries. Besides, the potential directions in this field are discussed in the end. Together, the recent advances reviewed here will act as a comprehensive overview of the roles of cellular senescence in IR injury, which could be of great significance for the design of related studies, or as a guide for potential therapeutic target.

Recent Advances in Epigenetics of Age-Related Kidney Diseases

Renal aging has attracted increasing attention in today’s aging society, as elderly people with advanced age are more susceptible to various kidney disorders such as acute kidney injury (AKI) and chronic kidney disease (CKD). There is no clear-cut universal mechanism for identifying age-related kidney diseases, and therefore, they pose a considerable medical and public health challenge. Epigenetics refers to the study of heritable modifications in the regulation of gene expression that do not require changes in the underlying genomic DNA sequence. A variety of epigenetic modifiers such as histone deacetylases (HDAC) inhibitors and DNA methyltransferase (DNMT) inhibitors have been proposed as potential biomarkers and therapeutic targets in numerous fields including cardiovascular diseases, immune system disease, nervous system diseases, and neoplasms. Accumulating evidence in recent years indicates that epigenetic modifications have been implicated in renal aging. However, no previous systematic review has been performed to systematically generalize the relationship between epigenetics and age-related kidney diseases. In this review, we aim to summarize the recent advances in epigenetic mechanisms of age-related kidney diseases as well as discuss the application of epigenetic modifiers as potential biomarkers and therapeutic targets in the field of age-related kidney diseases. In summary, the main types of epigenetic processes including DNA methylation, histone modifications, non-coding RNA (ncRNA) modulation have all been implicated in the progression of age-related kidney diseases, and therapeutic targeting of these processes will yield novel therapeutic strategies for the prevention and/or treatment of age-related kidney diseases.