Long Noncoding RNAs Regulate the Inflammatory Responses of Macrophages

Significance of LncRNAs in AKI-to-CKD transition: A therapeutic and diagnostic viewpoint

Acute kidney injury to chronic kidney disease (AKI-to-CKD) transition is a complex intermingling of characteristics of both AKI and CKD. Pathophysiologically, the transition lasts seven days after the AKI episode and thereafter silently progresses towards CKD. Growing reports confirm that the AKI-to-CKD transition is heavily regulated by epigenetic modifiers. Long non-coding RNAs (lncRNAs) share a diverse role in gene regulation at transcriptional and translational levels and have been reported to be involved in the regulation and progression of AKI-to-CKD transition. Several lncRNAs have been considered potential biomarkers for diagnosing kidney disease, including AKI and CKD. Targeting lncRNAs gives a promising therapeutic strategy against kidney diseases. The primitive role of lncRNA in the progression of the AKI-to-CKD transition is yet to be fully understood. As known, the lncRNAs could be used as a biomarker and a therapeutic target to halt the CKD development and progression after AKI. This review aims to deepen our understanding of the current knowledge regarding the involvement of lncRNAs in the AKI-to-CKD transition. This review primarily discusses the role of lncRNAs and the change in their mechanisms during different stages of kidney disease, such as in AKI, AKI-to-CKD transition, and CKD. Further, we have discussed the potential diagnostic and pharmacological outcomes of targeting lncRNAs to prevent or slow the progression of AKI-to-CKD transition.

Association of HOTAIR, MIR155HG, TERC, miR-155, -196a2, and -146a Genes Polymorphisms with Papillary Thyroid Cancer Susceptibility and Prognosis

Polymorphisms in long non-coding RNA and microRNA genes may play a significant role in the susceptibility and progression of papillary thyroid carcinoma (PTC). The current study investigates the polymorphisms HOTAIR rs920778, MIR155HG rs1893650, TERC rs10936599, miR-155 rs767649, miR-196a2 rs11614913 and miR-146a rs2910164 in 102 PTC patients and 106 age- and sex-matched controls of the Caucasian Serbian population, using real-time PCR. We observed differences in genotype distributions of the HOTAIR rs920778 (p = 0.016) and MIR155HG rs1893650 (p = 0.0002) polymorphisms between PTC patients and controls. HOTAIR rs920778 was associated with increased PTC susceptibility (adjusted OR = 1.497, p = 0.021), with the TT variant genotype increasing the risk compared to the CC genotype (OR = 2.466, p = 0.012) and C allele carriers (CC + CT) (OR = 1.585, p = 0.006). The HOTAIR rs920778 TT genotype was associated with lymph node metastasis (p = 0.022), tumor recurrence (p = 0.016), and progression-free survival (p = 0.010) compared to C allele carriers. Multivariate Cox regression revealed that ATA risk (HR = 14.210, p = 0.000004) and HOTAIR rs920778 (HR = 2.811, p = 0.010) emerged as independent prognostic factors in PTC. A novel polymorphism, MIR155HG rs1893650, was negatively correlated with susceptibility to PTC, with TC heterozygotes exerting a protective effect (OR = 0.268, p = 0.0001). These results suggest that the polymorphisms HOTAIR rs920778 and MIR155HG rs1893650 could be potential prognostic and risk biomarkers in papillary thyroid carcinomas.

LncRNA CASC2 Alleviates Renal Interstitial Inflammation and Fibrosis through MEF2C Downregulation-Induced Hinderance of M1 Macrophage Polarization

INTRODUCTION

Long noncoding RNA (lncRNA) cancer susceptibility candidate 2 (CASC2) alleviates the progression of diabetic nephropathy by inhibiting inflammation and fibrosis. This study investigated how CASC2 impacts renal interstitial fibrosis (RIF) through regulating M1 macrophage (M1) polarization.

METHOD

Nine-week-old mice underwent unilateral ureteral obstruction (UUO) establishment. Macrophages were induced toward M1 polarization using lipopolysaccharide (LPS) in vitro and cocultured with fibroblasts to examine how M1 polarization influences RIF. LnCeCell predicted that CASC2 interacted with myocyte enhancer factor 2 C (MEF2C), which was validated by dual-luciferase reporter assay. CASC2/MEF2C overexpression was achieved by lentivirus-expressing lncRNA CASC2 injection in vivo or CASC2 and MEF2C transfection in vitro. Renal injury was evaluated through biochemical analysis and hematoxylin-eosin/Masson staining. Macrophage infiltration and M1 polarization in the kidney and/or macrophages were detected by immunofluorescence, flow cytometry, and/or quantitative reverse transcription polymerase chain reaction (qRT-PCR). Expressions of CASC2, MEF2C, and markers related to inflammation/M1/fibrosis in the kidney/macrophages/fibroblasts were analyzed by qRT-PCR, fluorescence in situ hybridization, enzyme-linked immunosorbent assay, and/or Western blot.

RESULT

In the kidneys of mice, CASC2 was downregulated and macrophage infiltration was promoted time-dependently from days 3 to 14 post-UUO induction; CASC2 overexpression alleviated renal histological abnormalities, hindered macrophage infiltration and M1 polarization, downregulated renal function markers serum creatinine and blood urea nitrogen and inflammation/M1/fibrosis-related makers, and offset UUO-induced MEF2C upregulation. LncRNA CASC2 overexpression inhibited fibroblast fibrosis and M1 polarization in cocultured fibroblasts with LPS-activated macrophages. Also, CASC2 bound to MEF2C and inhibited its expression in LPS-activated macrophages. Furthermore, MEF2C reversed the inhibitory effects of lncRNA CASC2 overexpression.

CONCLUSION

CASC2 alleviates RIF by inhibiting M1 polarization through directly downregulating MEF2C expression. CASC2 might represent a promising value of future investigations on treatment for RIF.

Elsayed A, López-Berestein G, Amero P, Rodríguez-Aguayo C. An Overview of the Immune Modulatory Properties of Long Non-Coding RNAs and Their Potential Use as Therapeutic Targets in Cancer

Long non-coding RNAs (lncRNAs) play pivotal roles in regulating immune responses, immune cell differentiation, activation, and inflammatory processes. In cancer, they are gaining prominence as potential therapeutic targets due to their ability to regulate immune checkpoint molecules and immune-related factors, suggesting avenues for bolstering anti-tumor immune responses. Here, we explore the mechanistic insights into lncRNA-mediated immune modulation, highlighting their impact on immunity. Additionally, we discuss their potential to enhance cancer immunotherapy, augmenting the effectiveness of immune checkpoint inhibitors and adoptive T cell therapies. LncRNAs as therapeutic targets hold the promise of revolutionizing cancer treatments, inspiring further research in this field with substantial clinical implications.

Long Non-Coding RNAs and Their "Discrete" Contribution to IBD and Johne's Disease-What Stands out in the Current Picture? A Comprehensive Review

Non-coding RNAs (ncRNA) have paved the way to new perspectives on the regulation of gene expression, not only in biology and medicine, but also in associated fields and technologies, ensuring advances in diagnostic means and therapeutic modalities. Critical in this multistep approach are the associations of long non-coding RNA (lncRNA) with diseases and their causal genes in their networks of interactions, gene enrichment and expression analysis, associated pathways, the monitoring of the involved genes and their functional roles during disease progression from one stage to another. Studies have shown that Johne's Disease (JD), caused by Mycobacterium avium subspecies partuberculosis (MAP), shares common lncRNAs, clinical findings, and other molecular entities with Crohn's Disease (CD). This has been a subject of vigorous investigation owing to the zoonotic nature of this condition, although results are still inconclusive. In this review, on one hand, the current knowledge of lncRNAs in cells is presented, focusing on the pathogenesis of gastrointestinal-related pathologies and MAP-related infections and, on the other hand, we attempt to dissect the associated genes and pathways involved. Furthermore, the recently characterized and novel lncRNAs share common pathologies with IBD and JD, including the expression, molecular networks, and dataset analysis results. These are also presented in an attempt to identify potential biomarkers pertinent to cattle and human disease phenotypes.

Non-coding RNAs: emerging roles in the characterization of immune microenvironment and immunotherapy of prostate cancer

Prostate cancer is the most common tumor among men. Although the prognosis for early-stage prostate cancer is good, patients with advanced disease often progress to metastatic castration-resistant prostate cancer (mCRPC), which usually leads to death owing to resistance to existing treatments and lack of long-term effective therapy. In recent years, immunotherapy, especially immune checkpoint inhibitors (ICIs), has made great progress in the treatment of various solid tumors, including prostate cancer. However, the ICIs have only shown modest outcomes in mCRPC compared with other tumors. Previous studies have suggested that the suppressive tumor immune microenvironment (TIME) of prostate cancer leads to poor anti-tumor immune response and tumor resistance to immunotherapy. It has been reported that non-coding RNAs (ncRNAs) are capable of regulating upstream signaling at the transcriptional level, leading to a "cascade of changes" in downstream molecules. As a result, ncRNAs have been identified as an ideal class of molecules for cancer treatment. The discovery of ncRNAs provides a new perspective on TIME regulation in prostate cancer. ncRNAs have been associated with establishing an immunosuppressive microenvironment in prostate cancer through multiple pathways to modulate the immune escape of tumor cells which can promote resistance of prostate cancer to immunotherapy. Targeting these related ncRNAs presents an opportunity to improve the effectiveness of immunotherapy in this patient population.

lncRNA LOC100911717-targeting GAP43-mediated sympathetic remodeling after myocardial infarction in rats

Objective

Sympathetic remodeling after myocardial infarction (MI) is the primary cause of ventricular arrhythmias (VAs), leading to sudden cardiac death (SCD). M1-type macrophages are closely associated with inflammation and sympathetic remodeling after MI. Long noncoding RNAs (lncRNAs) are critical for the regulation of cardiovascular disease development. Therefore, this study aimed to identify the lncRNAs involved in MI and reveal a possible regulatory mechanism.

Methods and results

M0- and M1-type macrophages were selected for sequencing and screened for differentially expressed lncRNAs. The data revealed that lncRNA LOC100911717 was upregulated in M1-type macrophages but not in M0-type macrophages. In addition, the lncRNA LOC100911717 was upregulated in heart tissues after MI. Furthermore, an RNA pull-down assay revealed that lncRNA LOC100911717 could interact with growth-associated protein 43 (GAP43). Essentially, immunofluorescence assays and programmed electrical stimulation demonstrated that GAP43 expression was suppressed and VA incidence was reduced after lncRNA LOC100911717 knockdown in rat hearts using an adeno-associated virus.

Conclusions

We observed a novel relationship between lncRNA LOC100911717 and GAP43. After MI, lncRNA LOC100911717 was upregulated and GAP43 expression was enhanced, thus increasing the extent of sympathetic remodeling and the frequency of VA events. Consequently, silencing lncRNA LOC100911717 could reduce sympathetic remodeling and VAs.

An overview of natural products that modulate the expression of non-coding RNAs involved in oxidative stress and inflammation-associated disorders

Oxidative stress is a state in which oxidants are produced in excess in the body's tissues and cells, resulting in a biological imbalance amid the generation of reactive oxygen and nitrogen species (RONS) from redox reactions. In case of insufficient antioxidants to balance, the immune system triggers signaling cascades to mount inflammatory responses. Oxidative stress can have deleterious effects on major macromolecules such as lipids, proteins, and nucleic acids, hence, Oxidative stress and inflammation are among the multiple factors contributing to the etiology of several disorders such as diabetes, cancers, and cardiovascular diseases. Non-coding RNAs (ncRNAs) which were once referred to as dark matter have been found to function as key regulators of gene expression through different mechanisms. They have dynamic roles in the onset and development of inflammatory and oxidative stress-related diseases, therefore, are potential targets for the control of those diseases. One way of controlling those diseases is through the use of natural products, a rich source of antioxidants that have drawn attention with several studies showing their involvement in combating chronic diseases given their enormous gains, low side effects, and toxicity. In this review, we highlighted the natural products that have been reported to target ncRNAs as mediators of their biological effects on oxidative stress and several inflammation-associated disorders. Those natural products include Baicalein, Tanshinone IIA, Geniposide, Carvacrol/Thymol, Triptolide, Oleacein, Curcumin, Resveratrol, Solarmargine, Allicin, aqueous extract or pulp of Açai, Quercetin, and Genistein. We also draw attention to some other compounds including Zanthoxylum bungeanum, Canna genus rhizome, Fuzi-ganjiang herb pair, Aronia melanocarpa, Peppermint, and Gingerol that are effective against oxidative stress and inflammation-related disorders, however, have no known effect on ncRNAs. Lastly, we touched on the many ncRNAs that were found to play a role in oxidative stress and inflammation-related disorders but have not yet been investigated as targets of a natural product. Shedding more light into these two last points of shadow will be of great interest in the valorization of natural compounds in the control and therapy of oxidative stress- and inflammation-associated disorders.

Naringenin Prevents Oxidative Stress and Inflammation in LPS-Induced Liver Injury through the Regulation of LncRNA-mRNA in Male Mice

Inflammation accompanies hepatic dysfunction resulting from tissue oxidative damage. Naringenin (Nar), a natural flavanone, has known antioxidant and anti-inflammatory activities, but its mechanism of action in the regulation of liver dysfunction requires further investigation. In this study, the role of naringenin in lipopolysaccharide (LPS)-induced hepatic oxidative stress and inflammation was explored, as well as its mechanism by transcriptome sequencing. The results indicated that compared with the LPS group, Nar treatment caused a significant increase in the mRNA levels of antioxidant factors glutamate-cysteine ligase catalytic subunit (GCLC) and glutamate-cysteine ligase modifier subunit (GCLM), yet the expression of related inflammatory factors (MCP1, TNFα, IL-1β and IL-6) showed less of an increase. RNA sequencing identified 36 differentially expressed lncRNAs and 603 differentially expressed mRNAs. KEGG enrichment analysis indicated that oxidative stress and inflammation pathways are meticulously linked with naringenin treatment. The Co-lncRNA-mRNA network was also constructed. Tissue expression profiles showed that lncRNA played a higher role in the liver. Subsequently, expression levels of inflammatory factors indicated that lncRNAs and target mRNAs were significantly reduced after naringenin treatment in mouse liver AML12 cells and obese mouse. These results suggest that naringenin helps to prevent liver dysfunction through the regulation of lncRNA-mRNA axis to reduce oxidative stress and inflammatory factors.

p50-associated Cyclooxygenase-2 Extragenic RNA (PACER) and Long Non-coding RNA 13 (LNC13) as potential biomarkers for monitoring tuberculosis treatment

Gaps in early and accurate diagnosis, effective drug control, and treatment monitoring are hindering the global eradication effort of tuberculosis. This infectious disease has become the deadliest worldwide before the outbreak of Covid-19. The search for new molecular biomarkers of tuberculosis will help to reverse this trend. Long non-coding RNAs (lncRNAs) have emerged as important regulators of the host immune response to infection, hence their link with the etiology and diagnosis of tuberculosis has attracted some attention from the research community. However, very little is known about their potential for the monitoring of tuberculosis treatment. This study aimed at assessing the potential of two lncRNAs: p50-associated Cyclooxygenase-2 Extragenic RNA (PACER) and Long Non-coding RNA 13 (LNC13) in the monitoring of tuberculosis treatment. This was a cross-sectional study carried out in Douala, Cameroon from December 2020 to August 2021. A quantitative real-time polymerase chain reaction followed by Cq analysis using the Livak method were performed to measure the relative expression levels of PACER and LNC13 in whole blood of healthy controls, patients with active pulmonary tuberculosis at the initiation of treatment, after two, five, and six months into treatment. Receiver Operating Characteristic curves analysis was used to assess the ability of targeted lncRNAs to discriminate among those groups. The study showed that the lncRNAs PACER and LNC13 were significantly upregulated in patients with active pulmonary tuberculosis at the initiation of treatment than in healthy controls. The expression levels of the two lncRNAs were significantly downregulated in patients during the treatment as compared to the active pulmonary tuberculosis patients. However, the expression levels of the lncRNAs PACER and LNC13 in whole blood of patients after six months of treatment were similar to those in healthy controls. Similarly, lncRNAs PACER and LNC13 showed very good performance in distinguishing between active tuberculosis patients and healthy controls as well as in differentiating between newly diagnosed active tuberculosis patients and those under treatment. Interestingly, those lncRNAs could not discriminate healthy controls from patients after six months of treatment. The lncRNAs PACER and LNC13 are therefore potential biomarkers for the monitoring of tuberculosis treatment.