Role of miR-204 in the regulation of apoptosis, endoplasmic reticulum stress response, and inflammation in human trabecular meshwork cells

Identification of sex-specific biomarkers related to programmed cell death and analysis of immune cells in ankylosing spondylitis

Ankylosing spondylitis (AS) stands as a persistent inflammatory ailment predominantly impacting the axial skeleton, with the immune system and inflammation intricately entwined in its pathogenesis. This study endeavors to elucidate gender-specific patterns in immune cell infiltration and diverse forms of cell demise within the AS milieu. The aim is to refine the diagnosis and treatment of gender-specific AS patients, thereby advancing patient outcomes. In the pursuit of our investigation, two datasets (GSE25101 and GSE73754) pertinent to ankylosing spondylitis (AS) were meticulously collected and normalized from the GEO database. Employing the CIBERSORT algorithm, we conducted a comprehensive analysis of immune cell infiltration across distinct demographic groups and genders. Subsequently, we discerned differentially expressed genes (DEGs) associated with various cell death modalities in AS patients and their healthy counterparts. Our focus extended specifically to ferroptosis-related DEGs (FRDEGs), cuproptosis-related DEGs (CRDEGs), anoikis-related DEGs (ARDEGs), autophagy-related DEGs (AURDEGs), and pyroptosis-related DEGs (PRDEGs). Further scrutiny involved discerning disparities in these DEGs between AS patients and healthy controls, as well as disparities between male and female patients. Leveraging machine learning (ML) methodologies, we formulated disease prediction models employing cell death-related DEGs (CDRDEGs) and identified biomarkers intertwined with cell death in AS. Relative to healthy controls, a myriad of differentially expressed genes (DEGs) linked to cell death surfaced in AS patients. Among AS patients, 82 FRDEGs, 29 CRDEGs, 54 AURDEGs, 21 ARDEGs, and 74 PRDEGs were identified. In male AS patients, these numbers were 78, 33, 55, 24, and 94, respectively. Female AS patients exhibited 66, 41, 40, 17, and 82 DEGs in the corresponding categories. Additionally, 36 FRDEGs, 14 CRDEGs, 19 AURDEGs, 10 ARDEGs, and 36 PRDEGs exhibited differential expression between male and female AS patients. Employing machine learning techniques, LASSO, RF, and SVM-RFE were employed to discern key DEGs related to cell death (CDRDDEGs). The six pivotal CDRDDEGs in AS patients, healthy controls, were identified as CLIC4, BIRC2, MATK, PKN2, SLC25A5, and EDEM1. For male AS patients, the three crucial CDRDDEGs were EDEM1, MAP3K11, and TRIM21, whereas for female AS patients, COX7B, PEX2, and RHEB took precedence. Furthermore, the trio of DDX3X, CAPNS1, and TMSB4Y emerged as the key CDRDDEGs distinguishing between male and female AS patients. In the realm of immune correlation, the immune infiltration abundance in female patients mirrored that of healthy controls. Notably, key genes exhibited a positive correlation with T-cell CD4 memory activation when comparing male and female patient samples. This study engenders a more profound comprehension of the molecular underpinnings governing immune cell infiltration and cell death in ankylosing spondylitis (AS). Furthermore, the discernment of gender-specific disparities among AS patients underscores the clinical significance of these findings. By identifying DEGs associated with diverse cell death modalities, this study proffers invaluable insights into potential clinical targets for AS patients, taking cognizance of gender-specific nuances. The identification of gender-specific biological targets lays the groundwork for the development of tailored diagnostic and therapeutic strategies, heralding a pivotal step toward personalized care for AS patients.

Identification of sex-specific biomarkers related to programmed cell death and analysis of immune cells in ankylosing spondylitis

Ankylosing spondylitis (AS) stands as a persistent inflammatory ailment predominantly impacting the axial skeleton, with the immune system and inflammation intricately entwined in its pathogenesis. This study endeavors to elucidate gender-specific patterns in immune cell infiltration and diverse forms of cell demise within the AS milieu. The aim is to refine the diagnosis and treatment of gender-specific AS patients, thereby advancing patient outcomes. In the pursuit of our investigation, two datasets (GSE25101 and GSE73754) pertinent to ankylosing spondylitis (AS) were meticulously collected and normalized from the GEO database. Employing the CIBERSORT algorithm, we conducted a comprehensive analysis of immune cell infiltration across distinct demographic groups and genders. Subsequently, we discerned differentially expressed genes (DEGs) associated with various cell death modalities in AS patients and their healthy counterparts. Our focus extended specifically to ferroptosis-related DEGs (FRDEGs), cuproptosis-related DEGs (CRDEGs), anoikis-related DEGs (ARDEGs), autophagy-related DEGs (AURDEGs), and pyroptosis-related DEGs (PRDEGs). Further scrutiny involved discerning disparities in these DEGs between AS patients and healthy controls, as well as disparities between male and female patients. Leveraging machine learning (ML) methodologies, we formulated disease prediction models employing cell death-related DEGs (CDRDEGs) and identified biomarkers intertwined with cell death in AS. Relative to healthy controls, a myriad of differentially expressed genes (DEGs) linked to cell death surfaced in AS patients. Among AS patients, 82 FRDEGs, 29 CRDEGs, 54 AURDEGs, 21 ARDEGs, and 74 PRDEGs were identified. In male AS patients, these numbers were 78, 33, 55, 24, and 94, respectively. Female AS patients exhibited 66, 41, 40, 17, and 82 DEGs in the corresponding categories. Additionally, 36 FRDEGs, 14 CRDEGs, 19 AURDEGs, 10 ARDEGs, and 36 PRDEGs exhibited differential expression between male and female AS patients. Employing machine learning techniques, LASSO, RF, and SVM-RFE were employed to discern key DEGs related to cell death (CDRDDEGs). The six pivotal CDRDDEGs in AS patients, healthy controls, were identified as CLIC4, BIRC2, MATK, PKN2, SLC25A5, and EDEM1. For male AS patients, the three crucial CDRDDEGs were EDEM1, MAP3K11, and TRIM21, whereas for female AS patients, COX7B, PEX2, and RHEB took precedence. Furthermore, the trio of DDX3X, CAPNS1, and TMSB4Y emerged as the key CDRDDEGs distinguishing between male and female AS patients. In the realm of immune correlation, the immune infiltration abundance in female patients mirrored that of healthy controls. Notably, key genes exhibited a positive correlation with T-cell CD4 memory activation when comparing male and female patient samples. This study engenders a more profound comprehension of the molecular underpinnings governing immune cell infiltration and cell death in ankylosing spondylitis (AS). Furthermore, the discernment of gender-specific disparities among AS patients underscores the clinical significance of these findings. By identifying DEGs associated with diverse cell death modalities, this study proffers invaluable insights into potential clinical targets for AS patients, taking cognizance of gender-specific nuances. The identification of gender-specific biological targets lays the groundwork for the development of tailored diagnostic and therapeutic strategies, heralding a pivotal step toward personalized care for AS patients.

Decoding contextual crosstalk: revealing distinct interactions between non-coding RNAs and unfolded protein response in breast cancer

Breast cancer is significantly influenced by endoplasmic reticulum (ER) stress, impacting both its initiation and progression. When cells experience an accumulation of misfolded or unfolded proteins, they activate the unfolded protein response (UPR) to restore cellular balance. In breast cancer, the UPR is frequently triggered due to challenging conditions within tumors. The UPR has a dual impact on breast cancer. On one hand, it can contribute to tumor growth by enhancing cell survival and resistance to programmed cell death in unfavorable environments. On the other hand, prolonged and severe ER stress can trigger cell death mechanisms, limiting tumor progression. Furthermore, ER stress has been linked to the regulation of non-coding RNAs (ncRNAs) in breast cancer cells. These ncRNAs, including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), play essential roles in cancer development by influencing gene expression and cellular processes. An improved understanding of how ER stress and ncRNAs interact in breast cancer can potentially lead to new treatment approaches. Modifying specific ncRNAs involved in the ER stress response might interfere with cancer cell survival and induce cell death. Additionally, focusing on UPR-associated proteins that interact with ncRNAs could offer novel therapeutic possibilities. Therefore, this review provides a concise overview of the interconnection between ER stress and ncRNAs in breast cancer, elucidating the nuanced effects of the UPR on cell fate and emphasizing the regulatory roles of ncRNAs in breast cancer progression.

Enhanced expression of miR-204 attenuates LPS stimulated inflammatory injury through inhibiting the Wnt/β-catenin pathway via targeting CCND2

One of the most common bacterial diseases of the reproductive system in dairy cows is endometritis, which will cause huge economic loss. Here, we investigate the mechanisms of miR-204 on LPS-stimulated endometritis in vitro and in vivo. Experiments displayed that the expression of miR-204 was lower in bovine uterine tissue samples or bovine endometrial epithelial cell line (BEND) that stimulated by LPS. Compared with the negative group, miR-204 treatment significantly suppressed the production of proinflammatory factors and the Wnt/β-catenin pathway activation. Additionally, the result of the dual luciferase assay showed that miR-204 targeted cyclin D2. More importantly, up-regulation of miR-204 alleviated LPS induced uterine injury was confirmed in vivo studies. Molecular experiments indicated that the expression level of tight junctional proteins Claudin3 and cadherin1 were both enchanced by miR-204 treatment. Accordingly, miR-204 may serve as a new measure to prevent and treat endometritis caused by LPS.

SIRT1 regulates endoplasmic reticulum stress-related organ damage

Endoplasmic reticulum (ER) stress plays a key role in the pathogenesis of several organ damages. Studies show that excessive ER stress (ERS) can destroy cellular homeostasis, causing cell damage and physiological dysfunction in various organs. In recent years, Sirtuin1 (SIRT1) has become a research hotspot on ERS. Increasing evidence suggests that SIRT1 plays a positive role in various ERS-induced organ damage via multiple mechanisms, including inhibiting cellular apoptosis and promoting autophagy. SIRT1 can also alleviate liver, heart, lung, kidney, and intestinal damage by inhibiting ERS. We discuss the possible mechanism of SIRT1, explore potential therapeutic targets of diseases, and provide a theoretical basis for treating ERS-related diseases.

Roles of non-coding RNAs in eye development and diseases

The prevalence of ocular disorders is dramatically increasing worldwide, especially those that cause visual impairment and permanent loss of vision, including cataract, glaucoma, age-related macular degeneration, and diabetic retinopathy. Extensive evidence has shown that ncRNAs are key regulators in various biogenesis and biological functions, controlling gene expression related to histogenesis and cell differentiation in ocular tissues. Aberrant expression and function of ncRNA can lead to dysfunction of visual system and mediate progression of eye disorders. Here, we mainly offer an overview of the role of precise modulation of ncRNAs in eye development and function in patients with eye diseases. We also highlight the challenges and future perspectives in conducting ncRNA studies, focusing specifically on the role of ncRNAs that may hold expanded promise for their diagnostic and therapeutic applications in various eye diseases. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA in Disease and Development > RNA in Disease RNA in Disease and Development > RNA in Development.

MicroRNAs in Age-Related Proteostasis and Stress Responses

Aging is associated with the accumulation of damaged and misfolded proteins through a decline in the protein homeostasis (proteostasis) machinery, leading to various age-associated protein misfolding diseases such as Huntington's or Parkinson's. The efficiency of cellular stress response pathways also weakens with age, further contributing to the failure to maintain proteostasis. MicroRNAs (miRNAs or miRs) are a class of small, non-coding RNAs (ncRNAs) that bind target messenger RNAs at their 3'UTR, resulting in the post-transcriptional repression of gene expression. From the discovery of aging roles for lin-4 in C. elegans, the role of numerous miRNAs in controlling the aging process has been uncovered in different organisms. Recent studies have also shown that miRNAs regulate different components of proteostasis machinery as well as cellular response pathways to proteotoxic stress, some of which are very important during aging or in age-related pathologies. Here, we present a review of these findings, highlighting the role of individual miRNAs in age-associated protein folding and degradation across different organisms. We also broadly summarize the relationships between miRNAs and organelle-specific stress response pathways during aging and in various age-associated diseases.

Genome-wide post-transcriptional regulation of bovine mammary gland response to Streptococcus uberis

MicroRNAs (miRNAs) as post-transcriptionally regulators of gene expression have been shown to be critical regulators to fine-tuning immune responses, besides their criteria for being an ideal biomarker. The regulatory role of miRNAs in responses to most mastitis-causing pathogens is not well understood. Gram-positive Streptococcus uberis (Str. uberis), the leading pathogen in dairy herds, cause both clinical and subclinical infections. In this study, a system biology approach was used to better understand the main post-transcriptional regulatory functions and elements of bovine mammary gland response to Str. uberis infection. Publicly available miRNA-Seq data containing 50 milk samples of the ten dairy cows (five controls and five infected) were retrieved for this current research. Functional enrichment analysis of predicted targets revealed that highly confident responsive miRNAs (4 up- and 19 downregulated) mainly regulate genes involved in the regulation of transcription, apoptotic process, regulation of cell adhesion, and pro-inflammatory signaling pathways. Time series analysis showed that six gene clusters significantly differed in comparisons between Str. uberis-induced samples with controls. Additionally, other bioinformatic analysis, including upstream network analysis, showed essential genes, including TP53 and TGFB1 and some small molecules, including glucose, curcumin, and LPS, commonly regulate most of the downregulated miRNAs. Upregulated miRNAs are commonly controlled by the most important genes, including IL1B, NEAT1, DICER1 enzyme and small molecules including estradiol, tamoxifen, estrogen, LPS, and epigallocatechin. Our study used results of next-generation sequencing to reveal key miRNAs as the main regulator of gene expression responses to a Gram-positive bacterial infection. Furthermore, by gene regulatory network (GRN) analysis, we can introduce the common upregulator transcription factor of these miRNAs. Such milk-based miRNA signature(s) would facilitate risk stratification for large-scale prevention programs and provide an opportunity for early diagnosis and therapeutic intervention.

Context-Dependent Regulation of Gene Expression by Non-Canonical Small RNAs

In recent functional genomics studies, a large number of non-coding RNAs have been identified. It has become increasingly apparent that noncoding RNAs are crucial players in a wide range of cellular and physiological functions. They have been shown to modulate gene expression on different levels, including transcription, post-transcriptional processing, and translation. This review aims to highlight the diverse mechanisms of the regulation of gene expression by small noncoding RNAs in different conditions and different types of human cells. For this purpose, various cellular functions of microRNAs (miRNAs), circular RNAs (circRNAs), snoRNA-derived small RNAs (sdRNAs) and tRNA-derived fragments (tRFs) will be exemplified, with particular emphasis on the diversity of their occurrence and on the effects on gene expression in different stress conditions and diseased cell types. The synthesis and effect on gene expression of these noncoding RNAs varies in different cell types and may depend on environmental conditions such as different stresses. Moreover, noncoding RNAs play important roles in many diseases, including cancer, neurodegenerative disorders, and viral infections.

Expression and clinical significance of miR-204 in patients with hypertensive disorder complicating pregnancy

Objective

Hypertensive disorder complicating pregnancy (HDCP) is a unique and common obstetrical complication in pregnancy. The current study sought to investigate the diagnostic value of serum miR-204 in HDCP patients.

Methods

A total of 196 HDCP patients were enrolled, with 54 healthy pregnant women as controls. The expression levels of miR-204 and inflammatory factors in the serum were determined. Receiver operating characteristic (ROC) curve was used to assess the diagnostic value of miR-204 in HDCP patients. Person coefficient was introduced to analyze the correlation between miR-204 and inflammatory indexes. Kaplan–Meier method was employed to analyze the effect of miR-204 expression on the incidence of adverse pregnancy outcomes. Logistic regression was adopted to assess the risk factors for adverse pregnancy outcomes.

Results

miR-204 expression was upregulated in the serum of HDCP patients. The serum miR-204 level > 1.432 could assist the diagnosis of HDCP. miR-204 level in the serum was positively correlated with TNF-α, IL-6, and hs-CRP concentrations in HDCP patients. The risk of adverse outcomes was higher in pregnant women with high miR-204 expression. High miR-204 expression was associated with an increased risk of adverse pregnancy outcomes after adjusting the family history of HDCP, systolic pressure, diastolic pressure, AST, ALT, LDH, 24-h urinary protein, TNF-α, IL-6, and hs-CRP.

Conclusion

The high expression of miR-204 assists the diagnosis of HDCP and is an independent risk factor for adverse pregnancy outcomes in HDCP patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04501-9.

The role of microRNAs in glaucoma

In this review, we aim to provide a comprehensive summary of the various microRNAs (miRNAs) shown to be involved in glaucoma and intraocular pressure regulation. miRNAs are short, single-stranded, and noncoding RNAs that regulate gene expression in a number of physiological conditions and human diseases, including glaucoma. Numerous miRNAs display differential expression in glaucoma-affected tissues, such as aqueous humor, tears, trabecular meshwork, and retina analyzed from patients and animal models, suggesting their potential involvement in glaucoma pathogenesis. Several studies summarized here have also investigated the challenge of delivering intact miRNAs to target tissues in order to develop miRNA-based glaucoma therapies. We extend these reports by conducting an additional layer of analysis that integrates the interaction between glaucoma-related miRNAs and glaucoma-associated genes. We conclude with a comprehensive discussion of the therapeutic potential of miRNAs, the cellular pathways that link these miRNAs together, and the most promising miRNAs for future glaucoma research.

Non-coding RNA-based regulation of inflammation

Inflammation is a multifactorial process and various biological mechanisms and pathways participate in its development. The presence of inflammation is involved in pathogenesis of different diseases such as diabetes mellitus, cardiovascular diseases and even, cancer. Non-coding RNAs (ncRNAs) comprise large part of transcribed genome and their critical function in physiological and pathological conditions has been confirmed. The present review focuses on miRNAs, lncRNAs and circRNAs as ncRNAs and their potential functions in inflammation regulation and resolution. Pro-inflammatory and anti-inflammatory factors are regulated by miRNAs via binding to 3'-UTR or indirectly via affecting other pathways such as SIRT1 and NF-κB. LncRNAs display a similar function and they can also affect miRNAs via sponging in regulating levels of cytokines. CircRNAs mainly affect miRNAs and reduce their expression in regulating cytokine levels. Notably, exosomal ncRNAs have shown capacity in inflammation resolution. In addition to pre-clinical studies, clinical trials have examined role of ncRNAs in inflammation-mediated disease pathogenesis and cytokine regulation. The therapeutic targeting of ncRNAs using drugs and nucleic acids have been analyzed to reduce inflammation in disease therapy. Therefore, ncRNAs can serve as diagnostic, prognostic and therapeutic targets in inflammation-related diseases in pre-clinical and clinical backgrounds.

Epigenetic repression of Wnt receptors in AD: a role for Sirtuin2-induced H4K16ac deacetylation of Frizzled1 and Frizzled7 promoters

Growing evidence supports a role for deficient Wnt signalling in Alzheimer's disease (AD). First, the Wnt antagonist DKK1 is elevated in AD brains and is required for amyloid-β-induced synapse loss. Second, LRP6 Wnt co-receptor is required for synapse integrity and three variants of this receptor are linked to late-onset AD. However, the expression/role of other Wnt signalling components remain poorly explored in AD. Wnt receptors Frizzled1 (Fzd1), Fzd5, Fzd7 and Fzd9 are of interest due to their role in synapse formation/plasticity. Our analyses showed reduced FZD1 and FZD7 mRNA levels in the hippocampus of human early AD stages and in the hAPP^NLGF/NLGF mouse model. This transcriptional downregulation was accompanied by reduced levels of the pro-transcriptional histone mark H4K16ac and a concomitant increase of its deacetylase Sirt2 at Fzd1 and Fzd7 promoters in AD. In vitro and in vivo inhibition of Sirt2 rescued Fzd1 and Fzd7 mRNA expression and H4K16ac levels at their promoters. In addition, we showed that Sirt2 recruitment to Fzd1 and Fzd7 promoters is dependent on FoxO1 activity in AD, thus acting as a co-repressor. Finally, we found reduced levels of SIRT2 inhibitory phosphorylation in nuclear samples from human early AD stages with a concomitant increase in the SIRT2 phosphatase PP2C. This results in hyperactive nuclear Sirt2 and favours Fzd1 and Fzd7 repression in AD. Collectively, our findings define a novel role for nuclear hyperactivated SIRT2 in repressing Fzd1 and Fzd7 expression via H4K16ac deacetylation in AD. We propose SIRT2 as an attractive target to ameliorate AD pathology.

Identifying Diagnostic MicroRNAs and Investigating Their Biological Implications in Rectal Cancer

IMPORTANCE

Accurate clinical staging is important in rectal cancer because it determines the appropriate treatment and prognosis. Despite the use of multiple diagnostic imaging tools, it is sometimes difficult to clinically distinguish stage I tumors from stage II or III locally advanced disease. Identification of differentiating microRNAs (miRNAs) between these 2 groups may improve the clinical diagnostic power and provide insight into the biology of tumor progression.

OBJECTIVES

To investigate differences in the expression of miRNAs in stage I vs stage II or III rectal cancers and integrate matched mRNA profiling data to identify possible functional roles of these miRNAs.

DESIGN, SETTING, AND PARTICIPANTS

The primary tumor specimens from patients who were enrolled in 2 prospective clinical trials between March 24, 2004, and November 16, 2012 (American College of Surgeons Oncology Group [ACOSOG] Z6041 and Timing of Rectal Cancer Response to Chemoradiation [TIMING]) were sequenced to arrive at a set of 127 cases (41 stage I and 86 stage II or III tumors) with matched miRNA and messenger RNA (mRNA) profiling data. These findings were also evaluated in an independent cohort of 127 patient specimens (29 stage I and 98 stage II or III tumors) from The Cancer Genome Atlas Rectum Adenocarcinoma (TCGA-READ) that also had matched miRNA and mRNA data. Data analysis was performed from September 1, 2019, to September 1, 2020.

MAIN OUTCOMES AND MEASURES

Alterations in miRNA expression between stage I and stage II or III tumors and their potential gene targets.

RESULTS

A total of 254 pretreatment rectal adenocarcinoma specimens were analyzed in this study as 2 distinct cohorts: 127 samples in the ACOSOG/TIMING (stage I group: 27 [66%] male; mean [SD] age, 64.4 [10.8] years; stage II or III group: 47 [55%] male; mean [SD] age, 57.0 [11.4] years), and another 127 samples from TCGA-READ (stage I group: 17 [59%] male; mean [SD] age, 63.6 [12.0] years; stage II or III group: 48 [49%] male; mean [SD] age, 64.5 [11.4] years). A total of 19 miRNAs were overexpressed in stage II or III vs stage I tumors in both cohorts. This miRNA signature had an excellent discriminative value for distinguishing stage II or III from stage I rectal tumors (area under the curve, 0.88; 95% CI, 0.83-0.94 in ACOSOG/TIMING cohort and area under the curve, 0.84; 95% CI, 0.77-0.91 in the TCGA-READ cohort). Integrative analysis revealed 3 miRNA-mRNA pairs that exhibited significant correlations in both cohorts: miR-31-5p-SATB2, miR-143-3p-KLF5, and miR-204-5p-EZR.

CONCLUSIONS AND RELEVANCE

This diagnostic study found that many of the dysregulated miRNAs in stage II or III vs stage I rectal cancers have biological implications for tumor progression. The results of this study suggest that these miRNAs could assist as diagnostic biomarkers to better identify patients with locally advanced rectal cancer.

Circular RNA circFNDC3AL Upregulates BCL9 Expression to Promote Chicken Skeletal Muscle Satellite Cells Proliferation and Differentiation by Binding to miR-204

Skeletal muscle is a heterogeneous tissue that is essential for initiating movement and maintaining homeostasis. The genesis of skeletal muscle is an integrative process that lasts from embryonic development to postnatal stages, which is carried out under the modulation of many factors. Recent studies have shown that circular RNAs (circRNAs), a class of non-coding RNAs, are involved in myogenesis. However, more circRNAs and their mechanisms that may regulate skeletal muscle development remain to be explored. Through in-depth analysis of our previous RNA-Seq data, circFNDC3AL was found to be a potentially functional circRNA highly expressed during embryonic development of chicken skeletal muscle. Therefore, in this study, we investigated the effect of circFNDC3AL on skeletal muscle development in chickens and found that circFNDC3AL promoted chicken skeletal muscle satellite cell (SMSC) proliferation and differentiation. To gain a thorough understanding of the exact modulatory mechanisms of circFNDC3AL in chicken skeletal muscle development, we performed target miRNA analysis of circFNDC3AL and found that circFNDC3AL has a binding site for miR-204. Subsequently, we demonstrated that miR-204 inhibited chicken SMSC proliferation and differentiation, which showed the opposite functions of circFNDC3AL. Furthermore, we identified the miR-204 target gene B-cell CLL/lymphoma 9 (BCL9) and validated that miR-204 had an inhibitory effect on BCL9, while the negative effect could be relieved by circFNDC3AL. In addition, we verified that BCL9 performed the same positive functions on chicken SMSC proliferation and differentiation as circFNDC3AL, as opposed to miR-204. In conclusion, our study identified a circRNA circFNDC3AL that upregulates BCL9 expression to promote the proliferation and differentiation of chicken SMSCs by binding to miR-204.

The Future of Stem Cells and Their Derivates in the Treatment of Glaucoma. A Critical Point of View

This review focuses on the clinical translation of preclinical studies, especially those that have used stem cells in the treatment of glaucoma, with an emphasis on optic nerve regeneration. The studies referred to in the review aim to treat optic nerve atrophy, while cell therapies targeting other sites in the eye, such as the trabecular meshwork, have not been addressed. Such complex and varied pathophysiological mechanisms that lead to glaucoma may explain the fact that although stem cells have a high capacity of neuronal regeneration, the treatments performed did not have the expected results and the promise offered by animal studies was not achieved. By analyzing the facts associated with failure, important lessons are to be learned: the type of stem cells that are used, the route of administration, the selection of patients eligible for these treatments, additional therapies that support stem cells transplantation and their mode of action, methods of avoiding the host’s immune response. Many of these problems could be solved using exosomes (EV), but also miRNA, which allows more targeted approaches with minimal side effects.

Roles of miR-204 in retinal development and maintenance

The retina is the innermost part of the eye of most vertebrates and it is essential for vision. The development, maintenance, and function of this laminated structure is tightly regulated by numerous genes. Deficiencies in the expression of these genes as well as deregulation of various molecular mechanisms can cause retinopathies and blindness. MicroRNAs (miRNAs) are one of the most important and effective molecular regulatory mechanisms that underlie the biology of the retina. miRNAs have specific functional roles in the development and maintenance of different retinal layers and retinal cell types. While previous studies have reported a large number of miRNAs linked to development, maintenance and diseases of the retina, no comprehensive study has properly discussed and integrated data from these studies. Given the particular importance of miR-204 in retinal biology, we intend to critically discuss the expression and functional significance of this miRNA in the development, maintenance, and pathologies of the retina. Moreover, we explore biological processes through which miR-204 influences retinal pathophysiology. This review highlights the crucial functions of miR-204 in the retina and suggests the putative mechanism of miR-204 action in retinal biology.

Endoplasmic reticulum stress and muscle dysfunction in congenital lipodystrophies

Lipodystrophy syndromes are a group of rare diseases related to the pathological impairment of adipose tissue and metabolic comorbidities, including dyslipidemia, diabetes, insulin resistance, hypoleptinemia, and hypoadiponectinemia. They can be categorized as partial or generalized according to the degree of fat loss, and inherited or acquired disorders, if they are associated with genetic mutations or are related to autoimmunity, respectively. Some types of lipodystrophies have been associated with changes in both redox and endoplasmic reticulum (ER) homeostasis as well as muscle dysfunction (MD). Although ER stress (ERS) has been related to muscle dysfunction (MD) in many diseases, there is no data concerning its role in lipodystrophies' muscle physiopathology. Here we focused on congenital lipodystrophies associated with ERS and MD. We also described recent advances in our understanding of the relationships among ERS, MD, and genetic lipodystrophies, highlighting the adiponectin-protective roles.

An update: mechanisms of microRNA in primary open-angle glaucoma

Glaucoma is a disease with characteristic optic neuropathy and loss of vision, leading to blindness, and primary open-angle glaucoma (POAG) is the most common glaucoma type throughout the world. Genetic susceptibility is the main factor in POAG, and most susceptibility genes cause changes in microRNA expression and function, thereby leading to POAG occurrence and development. Increasing evidence indicates that many microRNAs are involved in the regulation of intraocular pressure (IOP) and play an important role in the increase in IOP in POAG. Additionally, microRNA is closely related to optic nerve damage factors (mechanical stress, hypoxia and inflammation). This review discusses the effect of single-nucleotide polymorphisms in POAG-related genes on microRNA and the value of microRNA in the diagnosis and treatment of POAG.

Overexpression of Rab40b Promotes Hepatocellular Carcinoma Cell Proliferation and Metastasis via PI3K/AKT Signaling Pathway

Background

Rab40b is an evolutionarily conserved Rab GTPase that plays an important role in intracellular trafficking and is closely related to cancer progression. However, the role and potential molecular mechanism of Rab40b in hepatocellular carcinoma (HCC) have not yet been elucidated.

Materials and Methods

The expression of Rab40b in HCC tissues and peritumour tissues was tested by qRT-PCR, Western blotting and histological analysis. A Kaplan-Meier survival curve was generated based on the expression of Rab40b in the HCC samples. Cell proliferation assays, wound healing assays, and transwell assays are used to examine the effect of Rab40b on HCC cell growth in vitro. The effect of Rab40b on cell cycle was examined by flow cytometry. A xenograft implantation model was used to assess the effect of Rab40b on the development of HCC cells in vivo.

Results

Rab40b protein expression is upregulated in HCC tissues, and this upregulation is associated with high pathological stage and poor prognosis in HCC patients. Rab40b overexpression promotes the proliferation and metastasis of HCC cells by upregulating cyclin D1, cyclin E1 and matrix metalloproteinase 2 (MMP2) through the PI3K/AKT signalling pathway. Conversely, Rab40b inhibitors can significantly inhibit the proliferation and metastasis of HCC cell lines and induce G0/G1 cell cycle arrest and apoptosis. Studies of a nude mouse xenograft model demonstrated that Rab40b knockdown can significantly inhibit the proliferation and progression of HCC tumours in vivo.

Conclusion

Overall, this study demonstrates that Rab40b is an important oncoprotein that promotes HCC progression by regulating the expression of cyclin D1, cyclin E1, p21 and MMP2 through the PI3K/AKT signalling pathway.

RETRACTED: Sevoflurane up-regulates microRNA-204 to ameliorate myocardial ischemia/reperfusion injury in mice by suppressing Cotl1

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figures 4C+E and 7E, which appear to have a similar phenotype as seen in many other publications, as detailed here: https://pubpeer.com/publications/CE1E814DD630D160BEEBFC2842FE45; and here: https://docs.google.com/spreadsheets/d/1r0MyIYpagBc58BRF9c3luWNlCX8VUvUuPyYYXzxWvgY/edit#gid=262337249. The journal requested that the corresponding author comment on these concerns and provide the raw data. The authors did not respond to this request and therefore the Editor-in-Chief decided to retract the article.

MicroRNAs and obesity-induced endothelial dysfunction: key paradigms in molecular therapy

The endothelium plays a pivotal role in maintaining vascular health. Obesity is a global epidemic that has seen dramatic increases in both adult and pediatric populations. Obesity perturbs the integrity of normal endothelium, leading to endothelial dysfunction which predisposes the patient to cardiovascular diseases. MicroRNAs (miRNAs) are short, single-stranded, non-coding RNA molecules that play important roles in a variety of cellular processes such as differentiation, proliferation, apoptosis, and stress response; their alteration contributes to the development of many pathologies including obesity. Mediators of obesity-induced endothelial dysfunction include altered endothelial nitric oxide synthase (eNOS), Sirtuin 1 (SIRT1), oxidative stress, autophagy machinery and endoplasmic reticulum (ER) stress. All of these factors have been shown to be either directly or indirectly caused by gene regulatory mechanisms of miRNAs. In this review, we aim to provide a comprehensive description of the therapeutic potential of miRNAs to treat obesity-induced endothelial dysfunction. This may lead to the identification of new targets for interventions that may prevent or delay the development of obesity-related cardiovascular disease.

Sweet Control: MicroRNA Regulation of the Glycome

Glycosylation is a sophisticated informational system that controls specific biological functions at the cellular and organismal level. Dysregulation of glycosylation may underlie some of the most complex and common diseases of the modern era. In the past 5 years, microRNAs have come to the forefront as a critical regulator of the glycome. Herein, we review the current literature on miRNA regulation of glycosylation and how this work may point to a new way to identify the biological importance of glycosylation enzymes.

SIRT1 is a key regulatory target for the treatment of the endoplasmic reticulum stress-related organ damage

Endoplasmic reticulum (ER) stress is an evolutionarily conserved adaptive response that contributes to deal with the misfolded or unfolded protein in the lumen of the ER and restore the ER homeostasis. However, excessive and prolonged ER stress can trigger the cell-death signaling pathway which causes cell death, usually in the form of apoptosis. It is generally accepted that inappropriate cellular apoptosis and a series of the subsequent inflammatory response and oxidative stress can cause disturbance of normal physiological functions and organ damage. A lot of evidence shows that the excessive activation of the ER stress contributes to the pathogenesis of many kinds of diseases and inhibiting the inappropriate stress is of great significance for maintaining the normal physiological function. In recent years, Sirtuin1 (SIRT1) has become a research hotspot on ER stress. As a master regulator of ER stress, increasing evidence suggests that SIRT1 plays a positive role in a variety of ER stress-induced organ damage via multiple mechanisms, including inhibiting cellular apoptosis and promoting autophagy. Furthermore, a lot of factors have shown effective regulation of SIRT1, which indicates the feasibility of treating SIRT1 as a target for the treatment of ER stress-related diseases. We summarize and reveal the molecular mechanisms underlying the protective effect of SIRT1 in multiple ER stress-mediated organ damage in this review. We also summed up the possible adjustment mechanism of SIRT1, which provides a theoretical basis for the treatment of ER stress-related diseases.

Homoharringtonine Inhibits Allergic Inflammations by Regulating NF-κB-miR-183-5p-BTG1 Axis

Homoharringtonine (HHT) is a drug for treatment of chronic myeloid leukemia. However, the role of HHT in allergic inflammations remains unknown. Mouse model of atopic dermatitis (AD) induced by 2, 4,-dinitroflurobenzene (DNFB) and anaphylaxis employing 2,4-dinitropheny-human serum albumin (DNP-HSA) were used to examine the role of HHT in allergic inflammations. HHT inhibited in vitro allergic reactions and attenuated clinical symptoms associated with AD. DNFB induced features of allergic reactions in rat basophilic leukemia (RBL2H3) cells. HHT suppressed effect of AD on the expression of Th1/Th2 cytokines. HHT inhibited passive cutaneous anaphylaxis and passive systemic anaphylaxis. MiR-183-5p, increased by antigen stimulation, was downregulated by HHT in RBL2H3 cells. MiR-183-5p inhibitor suppressed anaphylaxis and AD. B cell translocation gene 1 (BTG1) was shown to be a direct target of miR-183-5p. BTG1 prevented antigen from inducing molecular features of in vitro allergic reactions. AD increased the expression of NF-κB, and NF-κB showed binding to the promoter sequences of miR-183-5p. NF-κB and miR-183 formed positive feedback to mediate in vitro allergic reactions. Thus, HHT can be an anti-allergy drug. We present evidence that NF-κB-miR-183-5p-BTG1 axis can serve as target for development of anti-allergy drug.

BCL-w: apoptotic and non-apoptotic role in health and disease

The BCL-2 family of proteins integrates signals that trigger either cell survival or apoptosis. The balance between pro-survival and pro-apoptotic proteins is important for tissue development and homeostasis, while impaired apoptosis contributes to several pathologies and can be a barrier against effective treatment. BCL-w is an anti-apoptotic protein that shares a sequence similarity with BCL-X_L, and exhibits a high conformational flexibility. BCL-w level is controlled by a number of signaling pathways, and the repertoire of transcriptional regulators largely depends on the cellular and developmental context. As only a few disease-relevant genetic alterations of BCL2L2 have been identified, increased levels of BCL-w might be a consequence of abnormal activation of signaling cascades involved in the regulation of BCL-w expression. In addition, BCL-w transcript is a target of a plethora of miRNAs. Besides its originally recognized pro-survival function during spermatogenesis, BCL-w has been envisaged in different types of normal and diseased cells as an anti-apoptotic protein. BCL-w contributes to survival of senescent and drug-resistant cells. Its non-apoptotic role in the promotion of cell migration and invasion has also been elucidated. Growing evidence indicates that a high BCL-w level can be therapeutically relevant in neurodegenerative disorders, neuron dysfunctions and after small intestinal resection, whereas BCL-w inhibition can be beneficial for cancer patients. Although several drugs and natural compounds can bi-directionally affect BCL-w level, agents that selectively target BCL-w are not yet available. This review discusses current knowledge on the role of BCL-w in health, non-cancerous diseases and cancer.

TRPM3_miR-204: a complex locus for eye development and disease

First discovered in a light-sensitive retinal mutant of Drosophila, the transient receptor potential (TRP) superfamily of non-selective cation channels serve as polymodal cellular sensors that participate in diverse physiological processes across the animal kingdom including the perception of light, temperature, pressure, and pain. TRPM3 belongs to the melastatin sub-family of TRP channels and has been shown to function as a spontaneous calcium channel, with permeability to other cations influenced by alternative splicing and/or non-canonical channel activity. Activators of TRPM3 channels include the neurosteroid pregnenolone sulfate, calmodulin, phosphoinositides, and heat, whereas inhibitors include certain drugs, plant-derived metabolites, and G-protein subunits. Activation of TRPM3 channels at the cell membrane elicits a signal transduction cascade of mitogen-activated kinases and stimulus response transcription factors. The mammalian TRPM3 gene hosts a non-coding microRNA gene specifying miR-204 that serves as both a tumor suppressor and a negative regulator of post-transcriptional gene expression during eye development in vertebrates. Ocular co-expression of TRPM3 and miR-204 is upregulated by the paired box 6 transcription factor (PAX6) and mutations in all three corresponding genes underlie inherited forms of eye disease in humans including early-onset cataract, retinal dystrophy, and coloboma. This review outlines the genomic and functional complexity of the TRPM3_miR-204 locus in mammalian eye development and disease.

MicroRNA-204 as an Indicator of Severity of Pulmonary Hypertension in Children with Congenital Heart Disease Complicated with Pulmonary Hypertension

BACKGROUND The objective of this study was to investigate the changes and significance of microRNA-204 (miR-204) in children with congenital heart disease (CHD) complicated with pulmonary hypertension (PH). MATERIAL AND METHODS Fifty-two CHD patients with left-to-right shunt were divided into 3 groups according to preoperative pulmonary artery systolic pressure (PASP) detected by color Doppler echocardiography: a control group (PASP <30 mmHg), a mild PH group (PASP 30-49 mmHg), and a severe PH group (PASP >50 mmHg). Peripheral venous blood and supernatant were collected on an empty stomach at 1 h before surgery and 7 days after surgery. The expression of miR-204 in plasma was detected by RT-qPCR. RESULTS One hour before surgery and 7 days after surgery, plasma miR-204 expression was at a higher level than that in the mild PH group and higher than in the severe PH group. miR-204 expression in children in each group showed a decreasing trend after surgery. The mild PH and severe PH groups had lower plasma miR-204 expression and PASP after surgery than before surgery. In the mild PH and severe PH groups, plasma miR-204 expression was negatively correlated with PASP. In all 52 cases, plasma miR-204 expression was negatively correlated with PASP. CONCLUSIONS The plasma miR-204 expression in CHD children with PH was negatively correlated with the degree of PH, suggesting miR-204 may be involved in PH development, and miR-204 expression may be an indicator of PH severity.

MicroRNA-204 silencing relieves pain of cervical spondylotic radiculopathy by targeting GDNF

Cervical spondylosis may cause chronic neck pain, radiculopathy and/or myelopathy, and consequently results in severe brain damage. Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor for motoneurons. Accumulating microRNAs (miRNAs) have highlighted as critical regulators of GDNF signaling in the mediation of neuroinflammation and neuropathic pain. Hence, we performed this study to investigate the potential role of miR-204 in the neuropathic pain of cervical spondylotic radiculopathy (CSR) by targeting GDNF. A rat model of spinal cord compression (SCC) was established to stimulate a pathologic lesion. RT-qPCR and western blot assays characterized the downregulation of GDNF and the upregulation of miR-204 in spinal cord tissues of rats under the conditions of SCC. Moreover, miR-204 could directly target GDNF, as evidenced by dual-luciferase reporter gene assay. In order to elucidate the roles of miR-204 and GDNF in SCC-induced neuropathic pain, miR-204 sponge, GDNF, or shRNA against GDNF was introduced to the rats, followed by measurements for SCC-induced neuroinflammation and neuropathic pain. GDNF upregulation or miR-204 silencing was identified to reduce the spontaneous pain score, gait scores and cell apoptosis. Furthermore, GDNF upregulation or miR-204 silencing resulted in elevated amplitude of sensory-evoked potentials (SEPs), number of motoneurons, release of pro-inflammatory factors, TNF-α, and IL-1β in addition to an increase in the anti-inflammatory factor BDNF. Taken together, upregulation of GDNF induced by miR-204 silencing confers protection against SCC-induced pain in rat models, suggesting a potential therapeutic target for CSR treatment.

Dose and time effects of solar-simulated ultraviolet radiation on the in vivo human skin transcriptome

Background

Terrestrial ultraviolet (UV) radiation causes erythema, oxidative stress, DNA mutations and skin cancer. Skin can adapt to these adverse effects by DNA repair, apoptosis, keratinization and tanning.

Objectives

To investigate the transcriptional response to fluorescent solar‐simulated radiation (FSSR) in sun‐sensitive human skin in vivo.

Methods

Seven healthy male volunteers were exposed to 0, 3 and 6 standard erythemal doses (SED). Skin biopsies were taken at 6 h and 24 h after exposure. Gene and microRNA expression were quantified with next generation sequencing. A set of candidate genes was validated by quantitative polymerase chain reaction (qPCR); and wavelength dependence was examined in other volunteers through microarrays.

Results

The number of differentially expressed genes increased with FSSR dose and decreased between 6 and 24 h. Six hours after 6 SED, 4071 genes were differentially expressed, but only 16 genes were affected at 24 h after 3 SED. Genes for apoptosis and keratinization were prominent at 6 h, whereas inflammation and immunoregulation genes were predominant at 24 h. Validation by qPCR confirmed the altered expression of nine genes detected under all conditions; genes related to DNA repair and apoptosis; immunity and inflammation; pigmentation; and vitamin D synthesis. In general, candidate genes also responded to UVA1 (340–400 nm) and/or UVB (300 nm), but with variations in wavelength dependence and peak expression time. Only four microRNAs were differentially expressed by FSSR.

Conclusions

The UV radiation doses of this acute study are readily achieved daily during holidays in the sun, suggesting that the skin transcriptional profile of ‘typical’ holiday makers is markedly deregulated.

What's already known about this topic?

The skin's transcriptional profile underpins its adverse (i.e. inflammation) and adaptive molecular, cellular and clinical responses (i.e. tanning, hyperkeratosis) to solar ultraviolet radiation.

Few studies have assessed microRNA and gene expression in vivo in humans, and there is a lack of information on dose, time and waveband effects.

What does this study add?

Acute doses of fluorescent solar‐simulated radiation (FSSR), of similar magnitude to those received daily in holiday situations, markedly altered the skin's transcriptional profiles.

The number of differentially expressed genes was FSSR‐dose‐dependent, reached a peak at 6 h and returned to baseline at 24 h.

The initial transcriptional response involved apoptosis and keratinization, followed by inflammation and immune modulation. In these conditions, microRNA expression was less affected than gene expression.

Linked Comment:Hart. Br J Dermatol 2020; 182:1328–1329.

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Oxidative stress and antioxidants in the trabecular meshwork

Glaucoma is an age-dependent disease closely related to oxidative stress and is regarded as the second leading cause of irreversible blindness worldwide. In recent years, many studies have shown that morphological and functional abnormalities of the trabecular meshwork (TM) are closely related to glaucoma, especially with respect to oxidative stress. In this review, the mechanisms of oxidative stress in the TM and treatment strategies for this condition, including strategies involving antioxidants, noncoding RNAs and exogenous compounds, are discussed. Although many questions remain to be answered, the reviewed findings provide insights for further research on oxidative stress alleviation in glaucoma and suggest new targets for glaucoma prevention.

Identification of genes involved in glaucoma pathogenesis using combined network analysis and empirical studies

Glaucoma is a leading cause of blindness. We aimed in this study to identify genes that may make subtle and cumulative contributions to glaucoma pathogenesis. To this end, we identified molecular interactions and pathways that include transcription factors (TFs) FOXC1, PITX2, PAX6 and NFKB1 and various microRNAs including miR-204 known to have relevance to trabecular meshwork (TM) functions and/or glaucoma. TM tissue is involved in glaucoma pathogenesis. In-house microarray transcriptome results and data sources were used to identify target genes of the regulatory molecules. Bioinformatics analyses were done to filter TM and glaucoma relevant genes. These were submitted to network-creating softwares to define interactions, pathways and a network that would include the genes. The network was stringently scrutinized and minimized, then expanded by addition of microarray data and data on TF and microRNA-binding sites. Selected features of the network were confirmed by empirical studies such as dual luciferase assays, real-time PCR and western blot experiments and apoptosis assays. MYOC, WDR36, LTPBP2, RHOA, CYP1B1, OPA1, SPARC, MEIS2, PLEKHG5, RGS5, BBS5, ALDH1A1, NOMO2, CXCL6, FMNL2, ADAMTS5, CLOCK and DKK1 were among the genes included in the final network. Pathways identified included those that affect ECM properties, IOP, ciliary body functions, retinal ganglion cell viability, apoptosis, focal adhesion and oxidative stress response. The identification of many genes potentially involved in glaucoma pathology is consistent with its being a complex disease. The inclusion of several known glaucoma-related genes validates the approach used.

Downregulation of miR-320 Alleviates Endoplasmic Reticulum Stress and Inflammatory Response in 3T3-L1 Adipocytes

OBJECTIVE

MicroRNAs serve important roles in the regulation of endoplasmic reticulum stress (ERs). This study aimed to investigate the role of microRNA-320 (miR-320) in the development of ERs and the inflammatory response in 3T3-L1 adipocytes.

MATERIALS AND METHODS

The adipose tissue expression levels of miR-320 and ERs markers (GRP78, GRP94, Derlin-1 and CHOP) and the serum concentration of inflammatory cytokines (TNF-α, NF-κB and IL-6) in obese patients were evaluated using quantitative real-time RT-PCR or enzyme-linked immunosorbent assay. The correlation of miR-320 with genes involved in ERs and inflammation was analyzed. The effects of miR-320 on ERs and inflammation were explored using mature 3T3-L1 adipocytes, which were pretreated with palmitic acid (PA).

RESULTS

ERs markers and inflammatory cytokines were all upregulated in obese patients. Adipose tissue miR-320 expression was also increased in obese patients, and had positive correlations with the levels of ERs markers and inflammatory cytokines. After PA treatment, the levels of ERs markers and inflammatory cytokines were elevated significantly in 3T3-L1 adipocytes. Moreover, miR-320 expression was increased in the cells under ERs status. The upregulation of miR-320 could enhance the expression of ERs markers and inflammatory cytokines, but the downregulation of miR-320 resulted in the opposite results.

CONCLUSION

The data of this study indicate that miR-320 expression is upregulated in ERs status, and the downregulation of miR-320 ameliorates ERs and the inflammatory response in 3T3-L1 adipocytes. We consider that the approaches to decrease miR-320 expression may be novel therapeutic strategies for the treatment of obesity and obesity-related diseases.

miR-204-5p regulates cell proliferation, invasion, and apoptosis by targeting IL-11 in esophageal squamous cell carcinoma

Esophageal cancer (EC) is the world's eighth most common malignant neoplasm and is ranked as the sixth leading cause of death related to cancer. Aberrant microRNA (miRNA) expression has been reported to be associated with esophageal squamous cell carcinoma. However, the molecular mechanism of miR-204-5p in esophageal squamous cell carcinoma (ESCC) is not clear. Therefore, the aim of this study was to investigate the potential role of miR-204-5p in ESCC. In the present study, we found that miR-204-5p could affect ESCC proliferation, invasion, apoptosis, and cell cycle in cell and mouse models. A dual-luciferase reporter assay showed that miR-204-5p expression was negatively correlated with interleukin-11 (IL-11) expression. IL-11 overexpression reversed the suppressive effects of miR-204-5p in the cell lines. These results indicated that miR-204-5p functions as a tumor suppressor by directly targeting IL-11 in ESCC.

Upregulated Expression of MicroRNA-204-5p Leads to the Death of Dopaminergic Cells by Targeting DYRK1A-Mediated Apoptotic Signaling Cascade

MicroRNAs (miRs) downregulate or upregulate the mRNA level by binding to the 3′-untranslated region (3′UTR) of target gene. Dysregulated miR levels can be used as biomarkers of Parkinson’s disease (PD) and could participate in the etiology of PD. In the present study, 45 brain-enriched miRs were evaluated in serum samples from 50 normal subjects and 50 sporadic PD patients. The level of miR-204-5p was upregulated in serum samples from PD patients. An upregulated level of miR-204-5p was also observed in the serum and substantia nigra (SN) of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD. Expression of miR-204-5p increased the level of α-synuclein (α-Syn), phosphorylated (phospho)-α-Syn, tau, or phospho-tau protein and resulted in the activation of endoplasmic reticulum (ER) stress in SH-SY5Y dopaminergic cells. Expression of miR-204-5p caused autophagy impairment and activation of c-Jun N-terminal kinase (JNK)-mediated apoptotic cascade in SH-SY5Y dopaminergic cells. Our study using the bioinformatic method and dual-luciferase reporter analysis suggests that miR-204-5p positively regulates mRNA expression of dual-specificity tyrosine phosphorylation regulated kinase 1A (DYRK1A) by directly interacting with 3′UTR of DYRK1A. The mRNA and protein levels of DYRK1A were increased in SH-SY5Y dopaminergic cells expressing miR-204-5p and SN of MPTP-induced PD mouse model. Knockdown of DYRK1A expression or treatment of the DYRK1A inhibitor harmine attenuated miR-204-5p-induced increase in protein expression of phospho-α-Syn or phospho-tau, ER stress, autophagy impairment, and activation of JNK-mediated apoptotic pathway in SH-SY5Y dopaminergic cells or primary cultured dopaminergic neurons. Our results suggest that upregulated expression of miR-204-5p leads to the death of dopaminergic cells by targeting DYRK1A-mediated ER stress and apoptotic signaling cascade.

The miRNAs miR-211-5p and miR-204-5p modulate ER stress in human beta cells

miRNAs are a class of small non-coding RNAs that regulate gene expression. Type 1 diabetes is an autoimmune disease characterized by insulitis (islets inflammation) and pancreatic beta cell destruction. The pro-inflammatory cytokines interleukin 1 beta (IL1B) and interferon gamma (IFNG) are released during insulitis and trigger endoplasmic reticulum (ER) stress and expression of pro-apoptotic members of the BCL2 protein family in beta cells, thus contributing to their death. The nature of miRNAs that regulate ER stress and beta cell apoptosis remains to be elucidated. We have performed a global miRNA expression profile on cytokine-treated human islets and observed a marked downregulation of miR-211-5p. By real-time PCR and Western blot analysis, we confirmed cytokine-induced changes in the expression of miR-211-5p and the closely related miR-204-5p and downstream ER stress related genes in human beta cells. Blocking of endogenous miRNA-211-5p and miR-204-5p by the same inhibitor (it is not possible to block separately these two miRs) increased human beta cell apoptosis, as measured by Hoechst/propidium Iodide staining and by determination of cleaved caspase-3 activation. Interestingly, miRs-211-5p and 204-5p regulate the expression of several ER stress markers downstream of PERK, particularly the pro-apoptotic protein DDIT3 (also known as CHOP). Blocking CHOP expression by a specific siRNA partially prevented the increased apoptosis observed following miR-211-5p/miR-204-5p inhibition. These observations identify a novel crosstalk between miRNAs, ER stress and beta cell apoptosis in early type 1 diabetes.

Downregulation of miR-204 expression defines a highly aggressive subset of Group 3/Group 4 medulloblastomas

Genome-wide expression profiling studies have identified four core molecular subgroups of medulloblastoma: WNT, SHH, Group 3 and Group 4. Molecular markers are necessary for accurate risk stratification in the non-WNT subgroups due to the underlying heterogeneity in genetic alterations and overall survival. MiR-204 expression was evaluated in molecularly classified 260 medulloblastomas from an Indian cohort and in 763 medulloblastomas from the MAGIC cohort, SickKids, Canada. Low expression of miR-204 in the Group 3 / Group 4 tumors identify a highly aggressive subset of tumors having poor overall survival, in the two independent cohorts of medulloblastomas. Downregulation of miR-204 expression correlates with poor survival within the Group 4 as well indicating it as a valuable risk-stratification marker in the subgroup. Restoration of miR-204 expression in multiple medulloblastoma cell lines was found to inhibit their anchorage-independent growth, invasion potential and tumorigenicity. IGF2R was identified as a novel target of miR-204. MiR-204 expression resulted in downregulation of both M6PR and IGF2R that transport lysosomal proteases from the Golgi apparatus to the lysosomes. Consistent with this finding, miR-204 expression resulted in reduction in the levels of the lysosomal proteases in medulloblastoma cells. MiR-204 expression also resulted in inhibition of autophagy that is known to be dependent on the lysosomal degradation pathway and LC3B, a known miR-204 target. Treatment with HDAC inhibitors resulted in upregulation of miR-204 expression in medulloblastoma cells, suggesting therapeutic role for these inhibitors in the treatment of medulloblastomas. In summary, miR-204 is not only a valuable risk stratification marker in the combined cohort of Group 3 / Group 4 medulloblastomas as well as in the Group 4 itself, that has paucity of good prognostication markers, but also has therapeutic potential as indicated by its tumor suppressive effect on medulloblastoma cells.

MicroRNA-204-5p suppresses IL6-mediated inflammatory response and chemokine generation in HK-2 renal tubular epithelial cells by targeting IL6R

During the pathogenetic process of varied kidney diseases, renal tubules are the major sites in response to detrimental insults, including pro-inflammatory stimuli. MicroRNA-204-5p (miR-204-5p) can be detected in the renal tubular epithelial cells in the normal kidney; its expression, however, is downregulated in the kidney with pathological changes. This study aimed to investigate the role of miR-204-5p in interleukin 6 (IL6) mediated inflammatory response and chemokine production in HK-2 renal tubular cells. In HK-2 cells, the expression of miR-204-5p was downregulated in response to exogenous pro-inflammatory stimulus, tumor necrosis factor α (TNFα), or IL1β, while that of IL6 receptor α (IL6R) was upregulated. Dual-luciferase results confirmed that miRNA-204-5p directly targeted IL6R. In addition to suppressing IL6R expression, miRNA-204-5p agomir also inhibited the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in HK-2 cells exposed to exogenous IL6. Further, miRNA-204-5p suppressed the overproduction of pro-inflammatory mediators (cyclooxygenase 2 and prostaglandin E2) and chemokines (C–C motif chemokine ligand 2 and C–X–C motif chemokine ligand 8). The anti-inflammatory effects of miRNA-204-5p were attenuated when IL6R was reexpressed in HK-2 cells. Collectively, our study reveals that miR-204-5p inhibits the inflammation and chemokine generation in renal tubular epithelial cells by modulating the IL6/IL6R axis.

Circulating microRNA146b-5p is superior to C-reactive protein as a novel biomarker for monitoring inflammatory bowel disease

BACKGROUND

Owing to the importance of early treatment, simple and reliable methods for monitoring inflammatory bowel disease (IBD) are needed.

AIMS

To determine whether circulating microRNAs are reliable biomarkers for IBD monitoring.

METHODS

Serum levels of 17 candidate microRNAs were measured by quantitative real-time polymerase chain reaction in a discovery cohort (n = 120). Differentially expressed serum microRNAs were further investigated in an independent training cohort (n = 341). Correlations between relative microRNA levels and disease activity were evaluated. A disease control group was included to investigate the specificity of microRNA. Logistical regression was used to construct a microRNA classifier to identify endoscopic activity. Its predictive value was explored in the validation cohort (n = 66) using the area under the receiver operating characteristic curve (AUC).

RESULTS

Serum microRNA146b-5p (miR-146b-5p) expression was 2.87- and 2.72-fold higher in patients with Crohn's disease and ulcerative colitis, respectively, than in healthy controls. Serum miR-146b-5p was significantly correlated with disease activity and was more specific than C-reactive protein (CRP). A classifier was built for Crohn's disease, ie P [Endoscopically active] = 11+e2.937-0.737(miR-146b-5p)-0.008PLT , with a greater AUC of 0.869 [0.764-0.940] than that for CRP (0.680 [0.554-0.790]) (P = 0.0043).

CONCLUSIONS

MiR-146b-5p may better reflect mucosal inflammation in IBD than CRP. The Crohn's disease classifier developed in this study may be valuable for identifying endoscopic activity in patients with Crohn's disease.

Visual Defects and Ageing

Many diseases are related to age, among these neurodegeneration is particularly important. Alzheimer's disease Parkinson's and Glaucoma have many common pathogenic events including oxidative damage, Mitochondrial dysfunction, endothelial alterations and changes in the visual field. These are well known in the case of glaucoma, less in the case of neurodegeneration of the brain. Many other molecular aspects are common, such as the role of endoplasmic reticulum autophagy and neuronal apoptosis while others have been neglected due to lack of space such as inflammatory cytokine or miRNA. Moreover, the loss of specific neuronal populations, the induction of similar mechanisms of cell injury and the deposition of protein aggregates in specific anatomical areas are very similar events between these diseases. Intracellular and/or extracellular accumulation of protein aggregates is a key feature of many neurodegenerative disorders. The existence of abnormal protein aggregates has been documented in the RGCs of glaucomatous patients such as the anomalous Tau protein or the β-amyloid accumulations. Intra-cell catabolic processes also appear to be common in both glaucoma and neurodegeneration. They also help us to understand how the basis between these diseases is common and how the visual aspects can be a serious problem for those who are affected.

Lycium barbarum polysaccharides alleviate hydrogen peroxide-induced injury by up-regulation of miR-4295 in human trabecular meshwork cells

Glaucoma is a chronic neurodegenerative disease which produces damage to the optic nerve and causes sightlessness. Current remains lack of effective method for glaucoma. Lycium barbarum polysaccharides (LBPs) have pleiotropic effects on various diseases. However, the effect of LBPs on glaucoma remains unclear. The study aimed to clarify the protective effect of LBPs against hydrogen peroxide (H₂O₂)-induced oxidative damage in human trabecular meshwork (HTM) cells. HTM cells were exposed to H₂O₂ (0-400 μM) for 24 h to construct an oxidative damage model. Then, the different concentrations of LBPs (0-500 μg mL^-1) were used to pre-treated HTM cells, and cell viability, apoptosis, protein levels of pro-/cleaved-caspase-3 and pro-/cleaved-caspase-9, and reactive oxygen species (ROS) generations were detected. MicroRNA (miR)-4295 inhibitor and its control were transfected into HTM cells, and the biological functions of miR-4295 were assessed in H₂O₂ and LBPs treated cells. Phosphatidylinositol 3-kinase (PI3K)/protein Kinase B (AKT) and extracellular regulated protein kinases (ERK) pathways were determined by western blot assay. LBPs significantly promoted cell viability, reduced apoptosis, declined cleaved-caspase-3/-9 and ROS level in HTM cells after H₂O₂ administration. MiR-4295 expression was up-regulated in H₂O₂ and LBPs treated cells. The protective effect of LBPs on H₂O₂-injured HTM cells was obviously reversed by miR-4295 inhibition. LBPs activated PI3K/AKT and ERK signaling pathways through up-regulation of miR-4295 in H₂O₂-injured HTM cells. These data demonstrated that LBPs alleviated H₂O₂-induced injury by up-regulation of miR-4295 in HTM cells, indicating the protective effect of LBPs on HTM cells against oxidative damage.

LIM domain only 2 over-expression in prostate stromal cells facilitates prostate cancer progression through paracrine of Interleukin-11

Mechanisms of stromal-epithelial crosstalk are essential for Prostate cancer (PCa) tumorigenesis and progression. Peripheral zone of the prostate gland possesses a stronger inclination for PCa than transition zone. We previously found a variety of genes that differently expressed among different prostate stromal cells, including LIM domain only 2 (LMO2) which highly expressed in peripheral zone derived stromal cells (PZSCs) and PCa associated fibroblasts (CAFs) compared to transition zone derived stromal cells (TZSCs). Studies on its role in tumors have highlighted LMO2 as an oncogene. Herein, we aim to study the potential mechanisms of stromal LMO2 in promoting PCa progression. The in vitro cells co-culture and in vivo cells recombination revealed that LMO2 over-expressed prostate stromal cells could promote the proliferation and invasiveness of either prostate epithelial or cancer cells. Further protein array screening confirmed that stromal LMO2 stimulated the secretion of Interleukin-11 (IL-11), which could promote proliferation and invasiveness of PCa cells via IL-11 receptor α (IL11Rα) – STAT3 signaling. Moreover, stromal LMO2 over-expression could suppress miR-204-5p which was proven to be a negative regulator of IL-11 expression. Taken together, results of our study demonstrate that prostate stromal LMO2 is capable of stimulating IL-11 secretion and by which activates IL11Rα – STAT3 signaling in PCa cells and then facilitates PCa progression. These results may make stromal LMO2 responsible for zonal characteristic of PCa and as a target for PCa microenvironment-targeted therapy.

MiR-211 is essential for adult cone photoreceptor maintenance and visual function

MicroRNAs (miRNAs) are key post-transcriptional regulators of gene expression that play an important role in the control of fundamental biological processes in both physiological and pathological conditions. Their function in retinal cells is just beginning to be elucidated, and a few have been found to play a role in photoreceptor maintenance and function. MiR-211 is one of the most abundant miRNAs in the developing and adult eye. However, its role in controlling vertebrate visual system development, maintenance and function so far remain incompletely unexplored. Here, by targeted inactivation in a mouse model, we identify a critical role of miR-211 in cone photoreceptor function and survival. MiR-211 knockout (-/-) mice exhibited a progressive cone dystrophy accompanied by significant alterations in visual function. Transcriptome analysis of the retina from miR-211-/- mice during cone degeneration revealed significant alteration of pathways related to cell metabolism. Collectively, this study highlights for the first time the impact of miR-211 function in the retina and significantly contributes to unravelling the role of specific miRNAs in cone photoreceptor function and survival.

MicroRNA-204 inhibits cell migration and invasion in human cervical cancer by regulating transcription factor 12

Deregulated microRNAs (miRs) and their roles in carcinogenesis have attracted great attention in recent years. Although miR-204 was reportedly dysregulated in various types of cancer, its function and mechanism in cervical cancer remain unknown. The present study focused on the expression and mechanisms of miR-204 in cervical cancer development. Expression of miR-204 in cervical cancer tissues and non-tumor tissues was measured using PCR analysis. The effect of ectopic expression of miR-204 on cell motility was evaluated using wound-healing and Transwell invasion assays. Luciferase activity and western blot assays were used to verify the regulatory effect of miR-204 on its target gene. It was demonstrated that miR-204 was significantly decreased in primary cervical cancer tissues, and that downregulated miR-204 was associated with lymph node metastasis and poor survival. In addition, it was revealed that ectopic expression of miR-204 significantly inhibited the migratory and invasive ability of cervical cancer cells in vitro. In addition, bioinformatic prediction and experimental validation demonstrated that transcription factor 12 (TCF12) was a direct target of miR-204. Overexpression of TCF12 attenuated the inhibitory effect of miR-204 on cell motility. Taken together, the present data indicated that miR-204 is a metastasis-associated gene and may contribute to the progression of cervical cancer by regulating TCF12, providing novel insights, including that miR-204/TCF12 may be an important mechanism for cervical cancer metastasis.

MicroRNA-204 promotes vascular endoplasmic reticulum stress and endothelial dysfunction by targeting Sirtuin1

Endoplasmic reticulum (ER) stress has been implicated in vascular endothelial dysfunction of obesity, diabetes, and hypertension. MicroRNAs play an important role in regulating ER stress. Here we show that microRNA-204 (miR-204) promotes vascular ER stress and endothelial dysfunction by targeting the Sirtuin1 (Sirt1) lysine deacetylase. Pharmacologic ER stress induced by tunicamycin upregulates miR-204 and downregulates Sirt1 in the vascular wall/endothelium in vivo and in endothelial cells in vitro. Inhibition of miR-204 protects against tunicamycin-induced vascular/endothelial ER stress, associated impairment of endothelium-dependent vasorelaxation, and preserves endothelial Sirt1. A miR-204 mimic leads to ER stress and downregulates Sirt1 in endothelial cells. Knockdown of Sirt1 in endothelial cells, and conditional deletion of endothelial Sirt1 in mice, promotes ER stress via upregulation of miR-204, whereas overexpression of Sirt1 in endothelial cells suppresses miR-204-induced ER stress. Furthermore, increase in vascular reactive oxygen species induced by ER stress is mitigated by by miR-204 inhibition. Finally, nutritional stress in the form of a Western diet promotes vascular ER stress through miR-204. These findings show that miR-204 is obligatory for vascular ER stress and ER stress-induced vascular endothelial dysfunction, and that miR-204 promotes vascular ER stress via downregulation of Sirt1.

Inflammation-related microRNA expression level in the bovine milk is affected by mastitis

MicroRNA (miRNA) in tissue and liquid samples have been shown to be associated with many diseases including inflammation. We aimed to identify inflammation-related miRNA expression level in the bovine mastitis milk. Expression level of inflammation-related miRNA in milk from mastitis-affected and normal cows was analyzed using qPCR. We found that expression level of miR-21, miR-146a, miR-155, miR-222, and miR-383 was significantly upregulated in California mastitis test positive (CMT+) milk. We further analyzed these miRNA using a chip-based QuantStudio Digital PCR System. The digital PCR results correlated with those of qPCR, demonstrating upregulation of miR-21, miR-146a, miR-155, miR-222, and miR-383 in CMT+ milk. In conclusion, we identified miRNA that are upregulated in CMT+ milk. These miRNA exhibited sensitivity and specificity greater than 80% for differentiating between CMT+ milk and normal milk. Our findings suggest that inflammation-related miRNA expression level in the bovine milk was affected by mastitis, and miRNA in milk have potential for use as biomarkers of bovine mastitis.