MicroRNAs as Regulators of Immune and Inflammatory Responses: Potential Therapeutic Targets in Diabetic Nephropathy

The immune-inflammation factor is associated with diabetic nephropathy: evidence from NHANES 2013-2018 and GEO database

Diabetic nephropathy (DN) is a common secondary kidney disease. Immune and inflammatory responses play an influential role in the development of DN. This study aims to explore the role and mechanisms of immune- and inflammatory-related factors in DN. Participants from the NHANES 2013-2018 were included to evaluate the association between the SII and DN. Considering the skewed distribution of SII, log SII was used for subsequent analysis. Then, the DEGs were extracted from the GSE96804 dataset by the "limma" package of R, which were further screened out genes in the key module based on WGCNA. The intersection genes between DEGs and key module genes were the key genes for the following mechanism exploration. The CyTargetlinker plug-in of Cytoscape software was used to construct the drug-genes network. Molecular docking was used to calculate the binding affinity between potential drugs and the hub genes. Among the 8236 participants from NHANES 2013-2018, Log SII was significantly associated with DN (p < 0.05). DEG and WGCNA revealed 30 DN-related genes, which mainly regulated immune- and inflammation pathways, and the NOD-like receptor signaling pathway was the core pathway highly involved in the DN occurrence. Moreover, NAIP, ZFP36, and DUSP1 were identified as hub genes in DN progression and there was a strong binding interaction between resveratrol and DUSP1.In conclusion, immune inflammation plays an influential role in the occurrence and development of DN. SII is an effective diagnostic marker for DN and resveratrol might have potential value in treating DN.

Pathological mechanism of immune disorders in diabetic kidney disease and intervention strategies

Diabetic kidney disease is one of the most severe chronic microvascular complications of diabetes and a primary cause of end-stage renal disease. Clinical studies have shown that renal inflammation is a key factor determining kidney damage during diabetes. With the development of immunological technology, many studies have shown that diabetic nephropathy is an immune complex disease, and that most patients have immune dysfunction. However, the immune response associated with diabetic nephropathy and autoimmune kidney disease, or caused by ischemia or infection with acute renal injury, is different, and has a com-plicated pathological mechanism. In this review, we discuss the pathogenesis of diabetic nephropathy in immune disorders and the intervention mechanism, to provide guidance and advice for early intervention and treatment of diabetic nephropathy.

Isocitrate dehydrogenase 1 upregulation in urinary extracellular vesicles from proximal tubules of type 2 diabetic rats

Diabetic nephropathy (DN) is a major cause of chronic kidney disease. Microalbuminuria is currently the most common non-invasive biomarker for the early diagnosis of DN. However, renal structural damage may have advanced when albuminuria is detected. In this study, we sought biomarkers for early DN diagnosis through proteomic analysis of urinary extracellular vesicles (uEVs) from type 2 diabetic model rats and normal controls. Isocitrate dehydrogenase 1 (IDH1) was significantly increased in uEVs from diabetic model rats at the early stage despite minimal differences in albuminuria between the groups. Calorie restriction significantly suppressed the increase in IDH1 in uEVs and 24-hour urinary albumin excretion, suggesting that the increase in IDH1 in uEVs was associated with the progression of DN. Additionally, we investigated the origin of IDH1-containing uEVs based on their surface sugar chains. Lectin affinity enrichment and immunohistochemical staining showed that IDH1-containing uEVs were derived from proximal tubules. These findings suggest that the increase in IDH1 in uEVs reflects pathophysiological alterations in the proximal tubules and that IDH1 in uEVs may serve as a potential biomarker of DN in the proximal tubules.

Epigenetics of hypertension as a risk factor for the development of coronary artery disease in type 2 diabetes mellitus

Hypertension, a multifaceted cardiovascular disorder influenced by genetic, epigenetic, and environmental factors, poses a significant risk for the development of coronary artery disease (CAD) in individuals with type 2 diabetes mellitus (T2DM). Epigenetic alterations, particularly in histone modifications, DNA methylation, and microRNAs, play a pivotal role in unraveling the complex molecular underpinnings of blood pressure regulation. This review emphasizes the crucial interplay between epigenetic attributes and hypertension, shedding light on the prominence of DNA methylation, both globally and at the gene-specific level, in essential hypertension. Additionally, histone modifications, including acetylation and methylation, emerge as essential epigenetic markers linked to hypertension. Furthermore, microRNAs exert regulatory influence on blood pressure homeostasis, targeting key genes within the aldosterone and renin-angiotensin pathways. Understanding the intricate crosstalk between genetics and epigenetics in hypertension is particularly pertinent in the context of its interaction with T2DM, where hypertension serves as a notable risk factor for the development of CAD. These findings not only contribute to the comprehensive elucidation of essential hypertension but also offer promising avenues for innovative strategies in the prevention and treatment of cardiovascular complications, especially in the context of T2DM.

Deciphering the role of MicroRNAs in diabetic nephropathy: Regulatory mechanisms and molecular insights

A serious consequence of diabetes mellitus, diabetic nephropathy (DN) which causes gradual damage to the kidneys. Dietary changes, blood pressure control, glucose control, and hyperlipidemia are all important components of DN management. New research, however, points to microRNAs (miRNAs) as having a pivotal role in DN pathogenesis. Miniature non-coding RNA molecules such as miRNAs control gene expression and impact several biological processes. The canonical and non-canonical routes of miRNA biogenesis are discussed in this article. In addition, several important signaling pathways are examined in the study of miRNA regulation in DN. A deeper knowledge of these regulatory mechanisms would allow for a better understanding of the molecular basis of DN and the development of innovative therapeutic strategies. Finally, miRNAs show tremendous potential as DN diagnostic biomarkers and treatment targets, opening up promising avenues for further study and potential clinical use.

Synthesis and activity of arylcoumarin derivatives with therapeutic effects on diabetic nephropathy

In the literature, daidzein has been reported to exhibit cardiovascular protective effects and hypoglycemic activity in mice. We sought to design and synthesize a novel compound, SJ-6, an analog of daidzein, with improved hypoglycemic properties. Although SJ-6 demonstrated favorable hypoglycemic effects, its pharmacokinetic limitations prompted us to design and synthesize prodrugs of SJ-6. We conducted a comprehensive evaluation of the prodrugs, including in vitro and in vivo studies, such as cytotoxicity, absorption, distribution, metabolism, excretion, and toxicity (ADMET) simulation analysis, in vitro blood-brain barrier (BBB) permeability evaluation, compound effect on insulin resistance, oral glucose tolerance test (OGTT), in vivo plasma concentration testing, acute toxicity test in rats, and long-term gavage administration experiment. Furthermore, we examined the antidiabetic nephropathy activity of our lead compound, compound 10, which demonstrated superior efficacy compared with the positive control drug, metformin hydrochloride. Our findings suggest that compound 10 represents a promising lead compound for the prevention and treatment of diabetic nephropathy.

MicroRNAs: Key modulators of inflammation-associated diseases

Inflammation is a multifaceted biological and pathophysiological response to injuries, infections, toxins, and inflammatory mechanisms that plays a central role in the progression of various diseases. MicroRNAs (miRNAs) are tiny, 19-25 nucleotides long, non-coding RNAs that regulate gene expression via post-transcriptional repression. In this review, we highlight the recent findings related to the significant roles of miRNAs in regulating various inflammatory cascades and immunological processes in the context of many lifestyle-related diseases such as diabetes, cardiovascular diseases, cancer, etc. We also converse on how miRNAs can have a dual impact on inflammatory responses, suggesting that regulation of their functions for therapeutic purposes may be disease-specific.

MiR-29b Alleviates High Glucose-induced Inflammation and Apoptosis in Podocytes by Down-regulating PRKAB2

BACKGROUND

Podocyte injury and inflammatory response are the core contributors to the pathogenesis of diabetic nephropathy. This study aims to identify novel regulatory miRNAs and elucidate their underlying mechanisms, which will help us understand the pathogenesis of diabetic nephropathy more comprehensively.

MATERIALS AND METHODS

Different glucose concentrations were used to treat podocytes to mimic the pathology of diabetic nephropathy in vitro. Flow cytometry was used to determine cell apoptosis. Inflammatory cytokines released by podocytes were measured by using an enzymelinked immunosorbent assay (ELISA). Western Blot was used to detect the expression of PRKAB2 protein in podocytes.

RESULTS

Genecard and g: profiler results revealed that miR-29b might be involved in regulating HG-induced cell injury. QRT-PCR indicated that HG-induced downregulation of miR-29b in podocytes. MiR-29b knockdown promoted cell apoptosis and inflammatory response in podocytes. MiR-29b overexpression repressed cell apoptosis and inflammatory response induced by high glucose treatment in podocytes. Luciferase reporter assay and Western Blot showed that miR-29b targeted PRKAB2 to negatively regulate PRKAB2 expression directly. Knockdown of PRKAB2 reversed the increased cell apoptosis and inflammation induced by miR-29b inhibitors.

CONCLUSION

MiR-29b plays a role in inhibiting inflammation and apoptosis in high glucose (HG) treated podocytes by negatively regulating PRKAB2 expression. This study provides new potential targets and ideas for the treatment of diabetic nephropathy.

Promising renoprotective effect of gold nanoparticles and dapagliflozin in diabetic nephropathy via targeting miR-192 and miR-21

Diabetic nephropathy (DN) is a worldwide issue that eventually leads to end-stage renal failure, with limited therapeutic options. Prior research has revealed that gold nanoparticles (AuNPs) have a substantial antidiabetic impact. In addition, sodium-glucose cotransporter2 (SGLT2) inhibitors, including dapagliflozin (DAPA), had renoprotective impact on DN. Therefore, this research attempted to determine the potential AuNPs and DAPA impacts in ameliorating experimentally DN induction and the underlying mechanisms focusing on miR-192 and miR-21, correlating them with autophagy, apoptosis, fibrosis, and oxidative stress. Diabetes induction was through a single intraperitoneal streptozotocin (55 mg/kg) injection, and rats with diabetes received AuNPs (2.5 mg/kg/day) as well as DAPA (2 mg/kg/day) for 7 weeks as a treatment. AuNPs and DAPA treatment for 7 weeks substantially alleviated DN. AuNPs and DAPA significantly increased catalase (CAT) activity as well as serum total antioxidant capacity (TAC), along with a substantial decline in malondialdehyde (MDA). AuNPs and DAPA treatment alleviated renal fibrosis as they decreased transforming growth factorß1(TGF-ß1) as well as matrix metalloproteinase-2 (MMP-2) renal expression, decreased apoptosis through alleviating the proapoptotic gene (caspase-3) renal expression and increased the antiapoptotic gene (Bcl-2) renal expression, and increased autophagy as they increased LC-3 as well as Beclin-1 renal expression. Autophagy activation, inhibition of apoptosis, and renal fibrosis could be due to their inhibitory impact on miR-192 and miR-21 renal expression. AuNPs and DAPA have a protective effect on DN in rats by targeting miR-192 and miR-21 and their downstream pathways, including fibrosis, apoptosis, autophagy, and oxidative stress.

Identifying C1QB, ITGAM, and ITGB2 as potential diagnostic candidate genes for diabetic nephropathy using bioinformatics analysis

Background

Diabetic nephropathy (DN), the most intractable complication in diabetes patients, can lead to proteinuria and progressive reduction of glomerular filtration rate (GFR), which seriously affects the quality of life of patients and is associated with high mortality. However, the lack of accurate key candidate genes makes diagnosis of DN very difficult. This study aimed to identify new potential candidate genes for DN using bioinformatics, and elucidated the mechanism of DN at the cellular transcriptional level.

Methods

The microarray dataset GSE30529 was downloaded from the Gene Expression Omnibus Database (GEO), and the differentially expressed genes (DEGs) were screened by R software. We used Gene Ontology (GO), gene set enrichment analysis (GSEA), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis to identify the signal pathways and genes. Protein-protein interaction (PPI) networks were constructed using the STRING database. The GSE30122 dataset was selected as the validation set. Receiver operating characteristic (ROC) curves were applied to evaluate the predictive value of genes. An area under curve (AUC) greater than 0.85 was considered to be of high diagnostic value. Several online databases were used to predict miRNAs and transcription factors (TFs) capable of binding hub genes. Cytoscape was used for constructing a miRNA-mRNA-TF network. The online database 'nephroseq' predicted the correlation between genes and kidney function. The serum level of creatinine, BUN, and albumin, and the urinary protein/creatinine ratio of the DN rat model were detected. The expression of hub genes was further verified through qPCR. Data were analyzed statistically using Student's t-test by the 'ggpubr' package.

Results

A total of 463 DEGs were identified from GSE30529. According to enrichment analysis, DEGs were mainly enriched in the immune response, coagulation cascades, and cytokine signaling pathways. Twenty hub genes with the highest connectivity and several gene cluster modules were ensured using Cytoscape. Five high diagnostic hub genes were selected and verified by GSE30122. The MiRNA-mRNA-TF network suggested a potential RNA regulatory relationship. Hub gene expression was positively correlated with kidney injury. The level of serum creatinine and BUN in the DN group was higher than in the control group (unpaired t test, t = 3.391, df = 4, p = 0.0275, r = 0.861). Meanwhile, the DN group had a higher urinary protein/creatinine ratio (unpaired t test, t = 17.23, df = 16, p < 0.001, r = 0.974). QPCR results showed that the potential candidate genes for DN diagnosis included C1QB, ITGAM, and ITGB2.

Conclusions

We identified C1QB, ITGAM and ITGB2 as potential candidate genes for DN diagnosis and therapy and provided insight into the mechanisms of DN development at transcriptome level. We further completed the construction of miRNA-mRNA-TF network to propose potential RNA regulatory pathways adjusting disease progression in DN.

Neuroprotective Effects of Lactobacillus plantarum PS128 in a Mouse Model of Parkinson’s Disease: The Role of Gut Microbiota and MicroRNAs

Parkinson’s disease (PD) is a neurodegenerative disease characterized by motor deficits and marked neuroinflammation in various brain regions. The pathophysiology of PD is complex and mounting evidence has suggested an association with the dysregulation of microRNAs (miRNAs) and gut dysbiosis. Using a rotenone-induced PD mouse model, we observed that administration of Lactobacillus plantarum PS128 (PS128) significantly improved motor deficits in PD-like mice, accompanied by an increased level of dopamine, reduced dopaminergic neuron loss, reduced microglial activation, reduced levels of inflammatory factors, and enhanced expression of neurotrophic factor in the brain. Notably, the inflammation-related expression of miR-155-5p was significantly upregulated in the proximal colon, midbrain, and striatum of PD-like mice. PS128 reduced the level of miR-155-5p, whereas it increased the expression of suppressor of cytokine signaling 1 (SOCS1), a direct target of miR-155-5p and a critical inhibitor of the inflammatory response in the brain. Alteration of the fecal microbiota in PD-like mice was partially restored by PS128 administration. Among them, Bifidobacterium, Ruminiclostridium_6, Bacteroides, and Alistipes were statistically correlated with the improvement of rotenone-induced motor deficits and the expression of miR-155-5p and SOCS1. Our findings suggested that PS128 ameliorates motor deficits and exerts neuroprotective effects by regulating the gut microbiota and miR-155-5p/SOCS1 pathway in rotenone-induced PD-like mice.

Signature of micro RNA 146a/215 and IL-6/TGF-β levels in a cross-link axis between obesity and colorectal cancer

Numerous malignancies, including colorectal and liver cancers, are ultimately more likely to occur in obese people, and chronic inflammatory conditions have been linked to this association. We are attempting to determine the clinical relevance of the mechanisms controlling the microRNA (miR-215 and miR-146a) expression and transforming growth factor-β (TGF-β)/interleukin-6 (IL-6) in a cross-link axis between obesity and colorectal cancer (CRC). Study participants were divided into four groups: healthy controls; obese without colorectal cancer; non-obese colorectal cancer; and obese with colorectal cancer. Obese and CRC patients had markedly higher expression of IL-6 and TGF-β, as well as tumor biomarkers, such as carcinoembryonic antigen (CEA), carbohydrate antigen 19.9 (CA19.9), and alpha-fetoprotein (AFP) levels. The relative expression of microRNAs (miR-215 and miR-146a) was significantly lower in obese patients with colorectal cancer. BMI and the microRNAs(miR-215 and miR-146a) showed a substantial negative correlation. TGF-β was favorably linked with IL-6, cholesterol, triglyceride levels, and BMI. High levels of TGF-β and IL-6 in the blood indicate how intensely inflammation develops in obesity, which could increase the risk of colorectal cancer.

MicroRNA-25-5p negatively regulates TXNIP expression and relieves inflammatory responses of brain induced by lipopolysaccharide

Sepsis is one of the most common causes of death in patients suffering from severe infection or injury. Currently, a specific effective therapy remains to be established. In the present study, miR-25-5p, miR-105, miR-106b-5p, miR-154-3p, miR-20b-5p, miR-295-3p, miR-291-3p, miR-301b, miR-352, and miR-93-5p were predicted to target TXNIP mRNA from the databases of miRDB, Targetscan, and microT-CDS. The luciferase reporter assay confirmed that miR-25-5p negatively regulates TXNIP expression. The ELISA analyses and western blotting demonstrated that miR-25-5p downregulated the production of IL-1β, IL-6, IL-8, and TNF-α in lipopolysaccharide (LPS)-stimulated cells or rats, as well as the protein levels of TXNIP, NLRP3, and cleaved caspase-1. In addition, miR-25-5p increased the cell viability and decreased the apoptosis in LPS-stimulated CTX TNA2 cells and reduced the abnormal morphology of the brain in LPS-stimulated rats. Besides, miR-25-5p decreased the relative mean fluorescence intensity of DCF in LPS-stimulated CTX TNA2 cell, apoptosis, and protein levels of MnSOD and catalase in LPS-stimulated brains. These findings indicate that miR-25-5p downregulated LPS-induced inflammatory responses, reactive oxygen species production, and brain damage, suggesting that miR-25-5p is a candidate treatment for septic encephalopathy.

Polyphenols target miRNAs as a therapeutic strategy for diabetic complications

MiRNAs are a large group of non-coding RNAs which participate in different cellular pathways like inflammation and oxidation through transcriptional, post-transcriptional, and epigenetic regulation. In the post-transcriptional regulation, miRNA interacts with the 3'-UTR of mRNAs and prevents their translation. This prevention or dysregulation can be a cause of pathological conditions like diabetic complications. A huge number of studies have revealed the association between miRNAs and diabetic complications, including diabetic nephropathy, cardiomyopathy, neuropathy, retinopathy, and delayed wound healing. To address this issue, recent studies have focused on the use of polyphenols as selective and safe drugs in the treatment of diabetes complications. In this article, we will review the involvement of miRNAs in diabetic complications' occurrence or development. Finally, we will review the latest findings on targeting miRNAs by polyphenols like curcumin, resveratrol, and quercetin for diabetic complications therapy.

Novel strategies to improve chicken performance and welfare by unveiling host-microbiota interactions through hologenomics

Fast optimisation of farming practices is essential to meet environmental sustainability challenges. Hologenomics, the joint study of the genomic features of animals and the microbial communities associated with them, opens new avenues to obtain in-depth knowledge on how host-microbiota interactions affect animal performance and welfare, and in doing so, improve the quality and sustainability of animal production. Here, we introduce the animal trials conducted with broiler chickens in the H2020 project HoloFood, and our strategy to implement hologenomic analyses in light of the initial results, which despite yielding negligible effects of tested feed additives, provide relevant information to understand how host genomic features, microbiota development dynamics and host-microbiota interactions shape animal welfare and performance. We report the most relevant results, propose hypotheses to explain the observed patterns, and outline how these questions will be addressed through the generation and analysis of animal-microbiota multi-omic data during the HoloFood project.

Podocyte-specific deletion of miR-146a increases podocyte injury and diabetic kidney disease

Diabetic glomerular injury is a major complication of diabetes mellitus and is the leading cause of end stage renal disease (ESRD). Healthy podocytes are essential for glomerular function and health. Injury or loss of these cells results in increased proteinuria and kidney dysfunction and is a common finding in various glomerulopathies. Thus, mechanistic understanding of pathways that protect podocytes from damage are essential for development of future therapeutics. MicroRNA-146a (miR-146a) is a negative regulator of inflammation and is highly expressed in myeloid cells and podocytes. We previously reported that miR-146a levels are significantly reduced in the glomeruli of patients with diabetic nephropathy (DN). Here we report generation of mice with selective deletion of miR-146a in podocytes and use of these mice in models of glomerular injury. Induction of glomerular injury in C57BL/6 wildtype mice (WT) and podocyte-specific miR-146a knockout (Pod-miR146a-/-) animals via administration of low-dose lipopolysaccharide (LPS) or nephrotoxic serum (NTS) resulted in increased proteinuria in the knockout mice, suggesting that podocyte-expressed miR-146a protects these cells, and thus glomeruli, from damage. Furthermore, induction of hyperglycemia using streptozotocin (STZ) also resulted in an accelerated development of glomerulopathy and a rapid increase in proteinuria in the knockout animals, as compared to the WT animals, further confirming the protective role of podocyte-expressed miR-146a. We also confirmed that the direct miR-146a target, ErbB4, was significantly upregulated in the diseased glomeruli and erlotinib, an ErbB4 and EGFR inhibitor, reducedits upregulation and the proteinuria in treated animals. Primary miR146-/- podocytes from these animals also showed a basally upregulated TGFβ-Smad3 signaling in vitro. Taken together, this study shows that podocyte-specific miR-146a is imperative for protecting podocytes from glomerular damage, via modulation of ErbB4/EGFR, TGFβ, and linked downstream signaling.

Immune responses in diabetic nephropathy: Pathogenic mechanisms and therapeutic target

Diabetic nephropathy (DN) is a chronic, inflammatory disease affecting millions of diabetic patients worldwide. DN is associated with proteinuria and progressive slowing of glomerular filtration, which often leads to end-stage kidney diseases. Due to the complexity of this metabolic disorder and lack of clarity about its pathogenesis, it is often more difficult to diagnose and treat than other kidney diseases. Recent studies have highlighted that the immune system can inadvertently contribute to DN pathogenesis. Cells involved in innate and adaptive immune responses can target the kidney due to increased expression of immune-related localization factors. Immune cells then activate a pro-inflammatory response involving the release of autocrine and paracrine factors, which further amplify inflammation and damage the kidney. Consequently, strategies to treat DN by targeting the immune responses are currently under study. In light of the steady rise in DN incidence, this timely review summarizes the latest findings about the role of the immune system in the pathogenesis of DN and discusses promising preclinical and clinical therapies.

Anti-Inflammatory microRNAs for Treating Inflammatory Skin Diseases

Skin inflammation occurs due to immune dysregulation because of internal disorders, infections, and allergic reactions. The inflammation of the skin is a major sign of chronic autoimmune inflammatory diseases, such as psoriasis, atopic dermatitis (AD), and lupus erythematosus. Although there are many therapies for treating these cutaneous inflammation diseases, their recurrence rates are high due to incomplete resolution. MicroRNA (miRNA) plays a critical role in skin inflammation by regulating the expression of protein-coding genes at the posttranscriptional level during pathogenesis and homeostasis maintenance. Some miRNAs possess anti-inflammatory features, which are beneficial for mitigating the inflammatory response. miRNAs that are reduced in inflammatory skin diseases can be supplied transiently using miRNA mimics and agomir. miRNA-based therapies that can target multiple genes in a given pathway are potential candidates for the treatment of skin inflammation. This review article offers an overview of the function of miRNA in skin inflammation regulation, with a focus on psoriasis, AD, and cutaneous wounds. Some bioactive molecules can target and modulate miRNAs to achieve the objective of inflammation suppression. This review also reports the anti-inflammatory efficacy of these molecules through modulating miRNA expression. The main limitations of miRNA-based therapies are rapid biodegradation and poor skin and cell penetration. Consideration was given to improving these drawbacks using the approaches of cell-penetrating peptides (CPPs), nanocarriers, exosomes, and low-frequency ultrasound. A formulation design for successful miRNA delivery into skin and target cells is also described in this review. The possible use of miRNAs as biomarkers and therapeutic modalities could open a novel opportunity for the diagnosis and treatment of inflammation-associated skin diseases.

An Updated View of the Importance of Vesicular Trafficking and Transport and Their Role in Immune-Mediated Diseases: Potential Therapeutic Interventions

Cellular trafficking is the set of processes of distributing different macromolecules by the cell. This process is highly regulated in cells, involving a system of organelles (endomembranous system), among which are a great variety of vesicles that can be secreted from the cell, giving rise to different types of extracellular vesicles (EVs) that can be captured by other cells to modulate their function. The cells of the immune system are especially sensitive to this cellular traffic, producing and releasing different classes of EVs, especially in disease states. There is growing interest in this field due to the therapeutic and translational possibilities it offers. Different ways of taking advantage of the understanding of cell trafficking and EVs are being investigated, and their use as biomarkers or therapeutic targets is being investigated. The objective of this review is to collect the latest results and knowledge in this area with a specific focus on immune-mediated diseases. Although some promising results have been obtained, further knowledge is still needed, at both the basic and translational levels, to understand and modulate cellular traffic and EVs for better clinical management of these patients.

Bibliometric Study of Trends in the Diabetic Nephropathy Research Space from 2016 to 2020

Background

Diabetic nephropathy (DN) is one of the most common microvascular complications of diabetes mellitus (DM), but no bibliometric studies pertaining to DN have been published within the last 5 years.

Objectives

Most prior studies have focused on specific problems in the DN field. This study attempts to sort out and visualize the knowledge framework in this research space from a holistic and highly generalized perspective. Readers can quickly understand and master the knowledge regarding DN research conducted from 2016 to 2020, in addition to predicting future research hotspots and possible directions for development in this field in a comprehensive and scientifically valid manner.

Methods

Literature information, discourse matrices, and co-occurrence matrices were generated using BICOMB. gCLUTO was used for biclustering analyses and visualization. Strategic diagrams were generated using GraphPad Prism 5. The social network analysis (SNA) was analyzed and plotted using Ucinet 6.0 and Netdraw.

Results

In total, 55 high-frequency MeSH terms/MeSH subheadings were selected and grouped into 5 clusters in a biclustering analysis. These analyses revealed that extensive studies of the etiology, diagnosis, and treatment of DN have been conducted over the last 5 years, while further research regarding DN-related single nucleotide polymorphisms, miRNAs, and signal transduction are warranted as these research areas remain relatively immature.

Conclusion

Together, these results outline a robust knowledge structure pertaining to the field of DN-related research over the last 5 years, providing a valuable resource for readers by enabling the easy comprehension of relevant information. In addition, this analysis highlights predicted DN-related research directions and hotspots.

MiR-29a regulates cardiomyocyte apoptosis by targeting Bak1 in diabetic cardiomyopathy

This study sought to investigate the association between microRNA-29a (miR-29a) and cardiomyocyte apoptosis in diabetic cardiomyopathy (DCM). DCM rat model was established by treating rats with streptozotocin (STZ), followed by injection of NC or miR-29a-3p mimics into the myocardium of rats. High glucose (HG)-treated H9c2 cells were transfected with NC and miR-29a-3p mimics. DCM rats presented elevated levels of blood glucose, HbA1c, and blood pressure and urine output and decreased body weight and cardiac contractile function after modeling. MiR-29a was lowly expressed in STZ-treated rats and HG-treated H9c2 cells. Upregulation of miR-29a improved cardiac structure and function and attenuated, alleviated myocardial histological abnormalities and fibrosis, and lowered cardiomyocyte apoptosis in DCM rats. Meanwhile, HG promoted H9c2 cell apoptosis, while miR-29a overexpression attenuated the function of HG. Compared with control group, the protein expression of Bax, cleaved-caspase3 and Bak1 in DCM and HG group were significantly upregulated, and the expression of Bcl-2 and Mcl-1 were downregulated, while miR-29a overexpression exerted opposite effect. Bioinformatics prediction method and western blot revealed that miR-29a directly targeted Bak1 and downregulated Bak1 expression. Overall, miR-29a regulated STZ- and HG-induced cardiomyocyte apoptosis by targeting Bak1, providing a novel understanding of the pathogenesis of DCM.

Identification of CCL19 as a Novel Immune-Related Biomarker in Diabetic Nephropathy

Diabetic nephropathy (DN) is one of the major microvascular complications in diabetic patients and the leading cause of end-stage renal disease (ESRD). Previous studies found that immune-related genes and immune cell infiltration play important roles in the pathogenesis and development of DN. Therefore, this study aimed to explore immune-related biomarkers in DN. In this research, three microarray datasets that included 18 DN and 28 healthy tubule samples were downloaded and integrated as the training set to identify differentially expressed immune-related genes (DEIGs). A total of 63 DEIGs were identified, and most upregulated DEIGs were primarily involved in the inflammatory response and chemokine-mediated signaling pathways. The Microenvironment Cell Populations-counter (MCP-counter) algorithm was then used to estimate the abundance of infiltrated immune and stromal cell populations. According to DEIG, weighted gene coexpression network and protein–protein network analyses, CCL19 was identified as the hub immune-related biomarker. Moreover, the upregulated level of CCL19 was confirmed in other independent datasets as well as in in vitro experiments with high glucose. In summary, this study provides novel insights into the pathogenesis of diabetic nephropathy and identifies CCL19 as a potential critical gene of DN.

Bioinformatics Analysis of the Mechanisms of Diabetic Nephropathy via Novel Biomarkers and Competing Endogenous RNA Network

Diabetic nephropathy (DN) is one of the common chronic complications of diabetes with unclear molecular mechanisms, which is associated with end-stage renal disease (ESRD) and chronic kidney disease (CKD). Our study intended to construct a competing endogenous RNA (ceRNA) network via bioinformatics analysis to determine the potential molecular mechanisms of DN pathogenesis. The microarray datasets (GSE30122 and GSE30529) were downloaded from the Gene Expression Omnibus database to find differentially expressed genes (DEGs). GSE51674 and GSE155188 datasets were used to identified the differentially expressed microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), respectively. The DEGs between normal and DN renal tissues were performed using the Linear Models for Microarray (limma) package. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to reveal the mechanisms of DEGs in the progression of DN. The protein-protein interactions (PPI) of DEGs were carried out by STRING database. The lncRNA-miRNA-messenger RNA (mRNA) ceRNA network was constructed and visualized via Cytoscape on the basis of the interaction generated through the miRDB and TargetScan databases. A total of 94 significantly upregulated and 14 downregulated mRNAs, 31 upregulated and 121 downregulated miRNAs, and nine upregulated and 81 downregulated lncRNAs were identified. GO and KEGG pathways enriched in several functions and expression pathways, such as inflammatory response, immune response, identical protein binding, nuclear factor kappa b (NF-κB) signaling pathway, and PI3K-Akt signaling pathway. Based on the analysis of the ceRNA network, five differentially expressed lncRNAs (DElncRNAs) (SNHG6, KCNMB2-AS1, LINC00520, DANCR, and PCAT6), five DEmiRNAs (miR-130b-5p, miR-326, miR-374a-3p, miR-577, and miR-944), and five DEmRNAs (PTPRC, CD53, IRF8, IL10RA, and LAPTM5) were demonstrated to be related to the pathogenesis of DN. The hub genes were validated by using receiver operating characteristic curve (ROC) and real-time PCR (RT-PCR). Our research identified hub genes related to the potential mechanism of DN and provided new lncRNA-miRNA-mRNA ceRNA network that contributed to diagnostic and potential therapeutic targets for DN.

PP2 Ameliorates Renal Fibrosis by Regulating the NF-κB/COX-2 and PPARγ/UCP2 Pathway in Diabetic Mice

Renal fibrosis is characterized by glomerulosclerosis and tubulointerstitial fibrosis in diabetic nephropathy (DN). We aimed to evaluate the effects of PP2 on renal fibrosis of DN. GSE33744 and GSE86300 were downloaded from the GEO database. Firstly, 839 DEGs were identified between nondiabetic and diabetic mice renal glomerular samples. COX-2 was selected to assess the effects of PP2 on renal glomerulosclerosis. In db/db mice, PP2 decreased the expression of COX-2, phosphorylated p65, and fibrotic proteins, accompanied with attenuated renal glomerulosclerosis. In cultured glomerular mesangial cells, high glucose- (HG-) induced p65 phosphorylation and COX-2 expression were attenuated by PP2 or NF-κB inhibitor PDTC. PP2, PDTC, or COX-2 inhibitor NS-398 ameliorated abnormal proliferation and expression of fibrotic proteins induced by HG. Secondly, 238 DEGs were identified between nondiabetic and diabetic mice renal cortex samples. UCP2 was selected to assess the effects of PP2 on renal tubulointerstitial fibrosis. In db/db mice, PP2 decreased the expression of PPARγ and UCP2, accompanied with attenuated renal tubulointerstitial fibrosis and EMT. In cultured proximal tubular cells, HG-induced PPARγ and UCP2 expression was inhibited by PP2 or PPARγ antagonist GW9662. PP2, GW9662, or UCP2 shRNA ameliorated HG-induced EMT. These results indicated that PP2 ameliorated renal fibrosis in diabetic mice.

Activated Histone Acetyltransferase p300/CBP-Related Signalling Pathways Mediate Up-Regulation of NADPH Oxidase, Inflammation, and Fibrosis in Diabetic Kidney

Accumulating evidence implicates the histone acetylation-based epigenetic mechanisms in the pathoetiology of diabetes-associated micro-/macrovascular complications. Diabetic kidney disease (DKD) is a progressive chronic inflammatory microvascular disorder ultimately leading to glomerulosclerosis and kidney failure. We hypothesized that histone acetyltransferase p300/CBP may be involved in mediating diabetes-accelerated renal damage. In this study, we aimed at investigating the potential role of p300/CBP in the up-regulation of renal NADPH oxidase (Nox), reactive oxygen species (ROS) production, inflammation, and fibrosis in diabetic mice. Diabetic C57BL/6J mice were randomized to receive 10 mg/kg C646, a selective p300/CBP inhibitor, or its vehicle for 4 weeks. We found that in the kidney of C646-treated diabetic mice, the level of H3K27ac, an epigenetic mark of active gene expression, was significantly reduced. Pharmacological inhibition of p300/CBP significantly down-regulated the diabetes-induced enhanced expression of Nox subtypes, pro-inflammatory, and pro-fibrotic molecules in the kidney of mice, and the glomerular ROS overproduction. Our study provides evidence that the activation of p300/CBP enhances ROS production, potentially generated by up-regulated Nox, inflammation, and the production of extracellular matrix proteins in the diabetic kidney. The data suggest that p300/CBP-pharmacological inhibitors may be attractive tools to modulate diabetes-associated pathological processes to efficiently reduce the burden of DKD.

Cadherin and Wnt signaling pathways as key regulators in diabetic nephropathy

AIM

A recent meta-analysis of genome-wide linkage studies (GWLS) has identified multiple genetic regions suggestive of linkage with DN harboring hundreds of genes. Moving this number of genetic loci forward into biological insight is truly the next step. Here, we approach this challenge with a gene ontology (GO) analysis in order to yield biological and functional role to the genes, an over-representation test to find which GO terms are enriched in the gene list, pathway analysis, as well as protein network analysis.

METHOD

GO analysis was performed using protein analysis through evolutionary relationships (PANTHER) version 14.0 software and P-values less than 0.05 were considered statistically significant. GO analysis was followed by over-representation test for the identification of enriched terms. Statistical significance was calculated by Fisher's exact test and adjusted using the false discovery rate (FDR) for correction of multiple tests. Cytoscape with the relevant plugins was used for the construction of the protein network and clustering analysis.

RESULTS

The GO analysis assign multiple GO terms to the genes regarding the molecular function, the biological process and the cellular component, protein class and pathway analysis. The findings of the over-representation test highlight the contribution of cell adhesion regarding the biological process, integral components of plasma membrane regarding the cellular component, chemokines and cytokines with regard to protein class, while the pathway analysis emphasizes the contribution of Wnt and cadherin signaling pathways.

CONCLUSIONS

Our results suggest that a core feature of the pathogenesis of DN may be a disturbance in Wnt and cadherin signaling pathways, whereas the contribution of chemokines and cytokines need to be studied in additional studies.

The Emerging Landscapes of Long Noncoding RNA in Thyroid Carcinoma: Biological Functions and Clinical Significance

Thyroid carcinoma (TC) is one of the most prevalent primary endocrine tumors, and its incidence is steadily and gradually increasing worldwide. Accumulating evidence has revealed the critical functions of long noncoding RNAs (lncRNAs) in the tumorigenesis and development of TC. Many TC-associated lncRNAs have been documented to be implicated in TC malignant behaviors, including abnormal cell proliferation, enhanced stem cell properties and aggressiveness, and resistance to therapeutics, through interaction with proteins, DNA, or RNA or encoding small peptides. Therefore, further elucidating the lncRNA dysregulation sheds additional insights into TC tumorigenesis and progression and opens new avenues for the early diagnosis and clinical therapy of TC. In this review, we summarize the abnormal expression of lncRNA in TC and the fundamental characteristics in TC tumorigenesis and development. Additionally, we introduce the potential prognostic and therapeutic significance of lncRNAs in TC.

Epigenetics and Inflammation in Diabetic Nephropathy

Diabetic nephropathy (DN) leads to high morbidity and disability. Inflammation plays a critical role in the pathogenesis of DN, which involves renal cells and immune cells, the microenvironment, as well as extrinsic factors, such as hyperglycemia, chemokines, cytokines, and growth factors. Epigenetic modifications usually regulate gene expression via DNA methylation, histone modification, and non-coding RNAs without altering the DNA sequence. During the past years, numerous studies have been published to reveal the mechanisms of epigenetic modifications that regulate inflammation in DN. This review aimed to summarize the latest evidence on the interplay of epigenetics and inflammation in DN, and highlight the potential targets for treatment and diagnosis of DN.

Immunoinformatics and Molecular Docking Studies Predicted Potential Multiepitope-Based Peptide Vaccine and Novel Compounds against Novel SARS-CoV-2 through Virtual Screening

BACKGROUND

Coronaviruses (CoVs) are enveloped positive-strand RNA viruses which have club-like spikes at the surface with a unique replication process. Coronaviruses are categorized as major pathogenic viruses causing a variety of diseases in birds and mammals including humans (lethal respiratory dysfunctions). Nowadays, a new strain of coronaviruses is identified and named as SARS-CoV-2. Multiple cases of SARS-CoV-2 attacks are being reported all over the world. SARS-CoV-2 showed high death rate; however, no specific treatment is available against SARS-CoV-2.

METHODS

In the current study, immunoinformatics approaches were employed to predict the antigenic epitopes against SARS-CoV-2 for the development of the coronavirus vaccine. Cytotoxic T-lymphocyte and B-cell epitopes were predicted for SARS-CoV-2 coronavirus protein. Multiple sequence alignment of three genomes (SARS-CoV, MERS-CoV, and SARS-CoV-2) was used to conserved binding domain analysis.

RESULTS

The docking complexes of 4 CTL epitopes with antigenic sites were analyzed followed by binding affinity and binding interaction analyses of top-ranked predicted peptides with MHC-I HLA molecule. The molecular docking (Food and Drug Regulatory Authority library) was performed, and four compounds exhibiting least binding energy were identified. The designed epitopes lead to the molecular docking against MHC-I, and interactional analyses of the selected docked complexes were investigated. In conclusion, four CTL epitopes (GTDLEGNFY, TVNVLAWLY, GSVGFNIDY, and QTFSVLACY) and four FDA-scrutinized compounds exhibited potential targets as peptide vaccines and potential biomolecules against deadly SARS-CoV-2, respectively. A multiepitope vaccine was also designed from different epitopes of coronavirus proteins joined by linkers and led by an adjuvant.

CONCLUSION

Our investigations predicted epitopes and the reported molecules that may have the potential to inhibit the SARS-CoV-2 virus. These findings can be a step towards the development of a peptide-based vaccine or natural compound drug target against SARS-CoV-2.

Complement C7 is Specifically Expressed in Mesangial Cells and is a Potential Diagnostic Biomarker for Diabetic Nephropathy and is Regulated by miR-494-3p and miR-574-5p

BACKGROUND

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease, but it remains relatively underdiagnosed.

OBJECTIVE

In this study, we aimed to explore the key regulatory pathways and potential biomarkers related to DN using integrated bioinformatics analysis and validation.

METHODS

First, the microarray data of the GSE30528 and GSE96804 datasets were downloaded from the Gene Expression Omnibus (GEO) database, and differentially expressed genes (DEGs) were screened. Then, weighted gene coexpression network analysis (WGCNA), gene ontology (GO) annotation, gene set enrichment analysis (GSEA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed to identify key pathways and genes. qRT-PCR and receiver operating characteristic (ROC) curves were used to validate our results. Furthermore, single-cell RNA sequencing (scRNA-seq) data were reanalyzed to investigate the expression specificity of C7 in DN cells. An online database search and luciferase reporter assay identified the target relationship between miRNAs and C7.

RESULTS

The "complement and coagulation cascades" were significantly enriched, and complement C3 and C7 were candidate markers. The receiver operating characteristic (ROC) curve revealed that C7 had significant diagnostic value (AUC=0.865) in DN. Through scRNA-seq reanalysis, we found that C7 was specifically elevated in mesangial (MES) cells of DN. Moreover, we found that the expression of C7 was regulated by miR-494-3p and miR-574-5p.

CONCLUSION

This is the first study to reveal that C7 is specifically expressed in mesangial cells, is a potential diagnostic biomarker for diabetic nephropathy, and is regulated by miR-494-3p and miR-574-5p.