MiR-338-3p inhibits TNF-α-induced lipogenesis in human sebocytes

MicroRNA-specific targets for neuronal plasticity, neurotransmitters, neurotrophic factors, and gut microbes in the pathogenesis and therapeutics of depression

Depression is of great concern because of the huge burden, and it is impacted by various epigenetic modifications, e.g., histone modification, covalent modifications in DNA, and silencing mechanisms of non-coding protein genes, e.g., microRNAs (miRNAs). MiRNAs are a class of endogenous non-coding RNAs. Alternations in specific miRNAs have been observed both in depressive patients and experimental animals. Also, miRNAs are highly expressed in the central nervous system and can be delivered to different tissues via tissue-specific exosomes. However, the mechanism of miRNAs' involvement in the pathological process of depression is not well understood. Therefore, we summarized and discussed the role of miRNAs in depression. Conclusively, miRNAs are involved in the pathology of depression by causing structural and functional changes in synapses, mediating neuronal regeneration, differentiation, and apoptosis, regulating the gut microbes and the expression of various neurotransmitters and BDNF, and mediating inflammatory and immune responses. Moreover, miRNAs can predict the efficacy of antidepressant medications and explain the mechanism of action of antidepressant drugs and aerobic exercise to prevent and assist in treating depression.

Transcriptomics Revealed Differentially Expressed Transcription Factors and MicroRNAs in Human Diabetic Foot Ulcers

Non-healing diabetic foot ulcers (DFUs) not only significantly increase morbidity and mortality but also cost a lot and drain healthcare resources. Persistent inflammation, decreased angiogenesis, and altered extracellular matrix remodeling contribute to delayed healing or non-healing. Recent studies suggest an increasing trend of DFUs in diabetes patients, and non-healing DFYs increase the incidence of amputation. Despite the current treatment with offloading, dressing, antibiotics use, and oxygen therapy, the risk of amputation persists. Thus, there is a need to understand the molecular and cellular factors regulating healing in DFUs. The ongoing research based on proteomics and transcriptomics has predicted multiple potential targets, but there is no definitive therapy to enhance healing in chronic DFUs. Increased or decreased expression of various proteins encoded by genes, whose expression transcriptionally and post-transcriptionally is regulated by transcription factors (TFs) and microRNAs (miRs), regulates DFU healing. For this study, RNA sequencing was conducted on 20 DFU samples of ulcer tissue and non-ulcerated nearby healthy tissues. The IPA analysis revealed various activated and inhibited transcription factors and microRNAs. Further network analysis revealed interactions between the TFs and miRs and the molecular targets of these TFs and miRs. The analysis revealed 30 differentially expressed transcription factors (21 activated and 9 inhibited), two translational regulators (RPSA and EIF4G2), and seven miRs, including mir-486, mir-324, mir-23, mir-186, mir-210, mir-199, and mir-338 in upstream regulators (p < 0.05), while causal network analysis (p < 0.05) revealed 28 differentially expressed TFs (19 activated and 9 inhibited), two translational regulators (RPSA and EIF4G2), and five miRs including mir-155, mir-486, mir-324, mir-210, and mir-1225. The protein-protein interaction analysis revealed the interaction of various novel proteins with the proteins involved in regulating DFU pathogenesis and healing. The results of this study highlight many activated and inhibited novel TFs and miRs not reported in the literature so far, as well as the targeted molecules. Since proteins are the functional units during biological processes, alteration of gene expression may result in different proteoforms and protein species, making the wound microenvironment a complex protein interaction (proteome complexity). Thus, investigating the effects of these TFs and miRs on protein expression using proteomics and combining these results with transcriptomics will help advance research on DFU healing and delineate potential therapeutic strategies.

microRNA-338-3p suppresses lipopolysaccharide-induced inflammatory response in HK-2 cells

BACKGROUND

Inflammation is the most common cause of kidney damage, and inflammatory responses in a number of diseases are mediated by microRNA-338-3p (miR-338-3p). However, there are only a few reports which described the regulation of miR-338-3p in human proximal tubular cells. The goal of this study was to see how miR-338-3p affected lipopolysaccharide (LPS)-caused inflammatory response in HK-2 cells.

METHODS

LPS was used to construct an inflammatory model in HK-2 cells. miR-338-3p mimic was used to increase the levels of miR-338-3p in HK-2 cells. MTT, JC-1 staining, and apoptosis assays were used to detect cell viability, mitochondrial membrane potential (MMP), and apoptosis, respectively. The production of inflammatory factors and the levels of p38, p65, phospho-p65, phospho-p38, Bax, Bcl-2, cleaved caspase-9, and cleaved caspase-3 were investigated using real-time polymerase chain reaction, western blotting, or enzyme-linked immunosorbent assay.

RESULTS

The levels of miR-338-3p were significantly lower in serum from patients with sepsis-induced kidney injury compared to the serum from healthy volunteers (P < 0.05). LPS reduced the level of miR-338-3p in HK-2 cells (P < 0.05). HK-2 cell viability, mitochondrial membrane potential, and Bcl-2 mRNA and protein levels were decreased by LPS (all P < 0.05). Apoptosis, the mRNA and protein levels of inflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α) and Bax, and the levels of cleaved caspase-9 and caspase-3 were increased by LPS (all P < 0.05). Raising the level of miR-338-3p mitigated these effects of LPS (all P < 0.05).

CONCLUSION

LPS-induced inflammation in HK-2 cells is reduced by miR-338-3p.

Effective biomarkers and therapeutic targets of nerve-immunity interaction in the treatment of depression: an integrated investigation of the miRNA-mRNA regulatory networks

Background: Major depressive disorder (MDD) is an emotional condition that interferes with sufferers’ work and daily life. Numerous studies have found that miRNAs play a significant role in the development of MDD and can be utilized as a biomarker for its diagnosis and therapy. However, there have been few studies on nerve-immunity interaction treatment for the brains of MMD patients. Methods: The work is performed on microarray data. We analyzed the differences of miRNAs (GSE58105, GSE81152, GSE152267, and GSE182194) and mRNA (GSE19738, GSE32280, GSE44593, GSE53987, and GSE98793) in MDD and healthy samples from GEO datasets. FunRich was used to predict the transcription factors and target genes of the miRNAs, and TF and GO enrichment analyses were performed. Then, by comparing the differential expression of the anticipated target genes and five mRNAs, intersecting mRNAs were discovered. The intersecting genes were submitted to GO and KEGG analyses to determine their functions. These intersecting potential genes and pathways that linked to MDD in neurological and immunological aspects have been identified for future investigation. Results: We discovered five hub genes: KCND2, MYT1L, GJA1, CHL1, and SNAP25, which were all up-regulated genes. However, in MMD, the equivalent miRNAs, hsa-miR-206 and hsa-miR-338-3p, were both down-regulated. These miRNAs can activate or inhibit the T cell receptor signal pathway, JAK-STAT and other signal pathways, govern immune-inflammatory response, neuronal remodeling, and mediate the onset and development of MMD Conclusions: The results of a thorough bioinformatics investigation of miRNAs and mRNAs in MDD showed that miR-338-3P and miR-206 might be effective biomarkers and possible therapeutic targets for the treatment of MDD via nerve-immunity interaction.

MicroRNA Cross-Involvement in Acne Vulgaris and Hidradenitis Suppurativa: A Literature Review

Acne Vulgaris (AV) and Hidradenitis suppurativa (HS) are common chronic inflammatory skin conditions that affect the follicular units that often coexist or are involved in differential diagnoses. Inflammation in both these diseases may result from shared pathways, which may partially explain their frequent coexistence. MicroRNAs (miRNAs) are a class of endogenous, short, non-protein coding, gene-silencing or promoting RNAs that may promote various inflammatory diseases. This narrative review investigates the current knowledge regarding miRNAs and their link to AV and HS. The aim is to examine the role of these molecules in the pathogenesis of AV and HS and to identify possible common miRNAs that could explain the similar characteristics of these two diseases. Five miRNA (miR-155 miR-223-, miR-21, and miRNA-146a) levels were found to be altered in both HS and AV. These miRNAs are related to pathogenetic aspects common to both pathologies, such as the regulation of the innate immune response, regulation of the Th1/Th17 axis, and fibrosis processes that induce scar formation. This review provides a starting point for further studies aimed at investigating the role of miRNAs in AV and HS for their possible use as diagnostic-therapeutic targets.

Targeting microRNA for improved skin health

BACKGROUND

In human skin, miRNAs have important regulatory roles and are involved in the development, morphogenesis, and maintenance by influencing cell proliferation, differentiation, immune regulation, and wound healing. MiRNAs have been investigated for many years in various skin disorders such as atopic dermatitis, psoriasis, as well as malignant tumors. Only during recent times, cosmeceutical use of molecules/natural active ingredients to regulate miRNA expression for significant advances in skin health/care product development was recognized.

AIM

To review miRNAs with the potential to maintain and boost skin health and avoid premature aging by improving barrier function, preventing photoaging, hyperpigmentation, and chronological aging/senescence.

METHODS

Most of the cited articles were found through literature search on PubMed. The main search criteria was a keyword "skin" in combination with the following words: miRNA, photoaging, UV, barrier, aging, exposome, acne, wound healing, pigmentation, pollution, and senescence. Most of the articles reviewed for relevancy were published during the past 10 years.

RESULTS

All results are summarized in Figure 1, and they are based on cited references.

CONCLUSIONS

Thus, regulating miRNAs expression is a promising approach for novel therapy not only for targeting skin diseases but also for cosmeceutical interventions aiming to boost skin health.

The role of microRNA-338-3p in cancer: growth, invasion, chemoresistance, and mediators

Cancer still remains as one of the leading causes of death worldwide. Metastasis and proliferation are abnormally increased in cancer cells that subsequently, mediate resistance of cancer cells to different therapies such as radio-, chemo- and immune-therapy. MicroRNAs (miRNAs) are endogenous short non-coding RNAs that can regulate expression of target genes at post-transcriptional level and capable of interaction with mRNA-coding genes. Vital biological mechanisms including apoptosis, migration and differentiation are modulated by these small molecules. MiRNAs are key players in regulating cancer proliferation and metastasis as well as cancer therapy response. MiRNAs can function as both tumor-suppressing and tumor-promoting factors. In the present review, regulatory impact of miRNA-338-3p on cancer growth and migration is discussed. This new emerging miRNA can regulate response of cancer cells to chemotherapy and radiotherapy. It seems that miRNA-338-3p has dual role in cancer chemotherapy, acting as tumor-promoting or tumor-suppressor factor. Experiments reveal anti-tumor activity of miRNA-338-3p in cancer. Hence, increasing miRNA-338-3p expression is of importance in effective cancer therapy. Long non-coding RNAs, circular RNAs and hypoxia are potential upstream mediators of miRNA-338-3p in cancer. Anti-tumor agents including baicalin and arbutin can promote expression of miRNA-338-3p in suppressing cancer progression. These topics are discussed to shed some light on function of miRNA-338-3p in cancer cells.

Effects of Egr1 on pancreatic acinar intracellular trypsinogen activation and the associated ceRNA network

Acute pancreatitis (AP) is a common digestive disorder with high morbidity and mortality. The present study aimed to investigate the expression of early growth response protein 1 (Egr1), and the effect of competing endogenous (ce)RNA network on trypsinogen activation. Pancreatic acinar intracellular trypsinogen activation (PAITA) is an important event in the early stage of AP; however, the underlying mechanisms remain unclear. The present study used taurolithocholic acid 3-sulfate (TLC-S)-treated AR42J cells (pancreatic cell line) to establish a PAITA model. A gene microarray and bioinformatics analysis was performed to identify the potential key targets in PAITA. The results demonstrated that Egr1, an important transcription factor, was significantly overexpressed in PAITA. In Egr1 small interfering (si)RNA-transfected cells, Egr1 expression was decreased and trypsinogen activation was significantly decreased compared with negative control siRNA-transfected cells, indicating that in TLC-S-induced PAITA, overexpression of Egr1 enhanced trypsinogen activation. A ceRNA network [mRNA-microRNA (miRNA/miR)-long non-coding (lnc)RNA] generated using the PAITA model revealed that the effects of Egr1 on PAITA may be regulated by multiple ceRNA pairs, and the lncRNAs (including NONRATT022624 and NONRATT031002) and miRNAs [including Rattus norvegicus (rno)-miR-214-3p and rno-miR-764-5p] included in the ceRNA pairs may serve roles in PAITA by regulating the expression of Egr1. The results of the present study may provide novel targets for researching the underlying mechanisms of, and developing treatments for AP.

Putative Genes and Pathways Involved in the Acne Treatment of Isotretinoin via Microarray Data Analyses

Acne is the eighth most common disease worldwide. Disease burden of acne such as anxiety, reduced self-esteem, and facial scarring lowers the life quality of acne patients. Isotretinoin is the most potent treatment for moderate-severe acne. However, the adverse events of isotretinoin especially teratogenicity limit its use. This study aims at investigating the therapeutical mechanisms of isotretinoin using bioinformatics analysis. Differentially expressed genes (DEGs) were filtered from microarray datasets GSE10432, GSE10433, and GSE11792. Functional and pathway enrichment analyses of DEGs were performed. Protein–protein interaction (PPI) network and module analyses were also conducted based on DEGs. Using isotretinoin for 1 week, LCN2, PTGES, and GDF15 were upregulated and might mediate sebocytes apoptosis and thus decreased sebum production; CCL2 originated from activated TNF signaling pathway and S100A7 could be related with “acne-flare”. While treating with isotretinoin for 8 weeks, key genes were downregulated, including HMGCS1, HMGCR, FDFT1, MVD, IDI1, and FDPS, which may be associated with decreased sebum synthesis; HMGCS1, HMGCR, and FDFT1 also probably associated with apoptosis of sebocytes. There were only two common genes including ACSBG1 and BCAT2 which worked in both 1 week and 8 weeks and could associate with decreased sebum synthesis and apoptosis of sebocytes, respectively. These results indicate potential therapeutics and side effect mechanisms of isotretinoin in the acne treatment and provide a research direction to further investigate the therapeutic mechanism of isotretinoin and thus develop retinoid-like compounds with similar curative effect and without teratogenicity.

TRPV1, Targeted by miR-338-3p, Induces Neuropathic Pain by Interacting with NECAB2

A variety of studies have proposed that transient receptor potential vanilloid 1 (TRPV1) is involved in the progression of multiple diseases, including neuropathic pain. Although increased expression of TRPV1 in chronic constriction injury was described earlier, the underlying regulatory mechanisms of TRPV1 in neuropathic pain remain largely unknown. In our study, we constructed a chronic constriction injury (CCI) rat model to deeply analyze the mechanisms underlying TRPV1. RT-qPCR-indicated TRPV1 mRNA and protein expression were extremely upregulated in CCI rat dorsal spinal cord tissues. Then, TRPV1 was corroborated to interact with N-terminal EF-hand Ca²⁺-binding protein 2 (NECAB2). The mRNA and protein levels of NECAB2 were increased in CCI tissues. Moreover, TRPV1 and NECAB2 together regulated nociceptive procession-associated protein metabotropic glutamate receptor 5 (mGluR5), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2), and Ca²⁺ in isolated microglia of CCI rats. Moreover, TRPV1 upregulation apparently increased mechanical allodynia and thermal hyperalgesia as well as the expression of inflammation-associated genes (COX-2, TNF-α, and IL-6). In addition, downregulation of NECAB2 significantly decreased mechanical allodynia and thermal hyperalgesia as well as the expression of COX-2, TNF-α, and IL-6. Furthermore, TRPV1 was confirmed to be a downstream target of miR-338-3p. TRPV1 overexpression abolished the inhibitory effect by miR-338-3p elevation on neuropathic pain development. In summary, this study proved TRPV1, targeted by miR-338-3p, induced neuropathic pain by interacting with NECAB2, which provides a potential therapeutic target for neuropathic pain treatment.

Circ_0038467 regulates lipopolysaccharide-induced inflammatory injury in human bronchial epithelial cells through sponging miR-338-3p

Background

Pneumonia is a common acute lower respiratory infection in children and elders. Circular RNAs (circRNAs) have recently been uncovered to play important roles in pneumonia. However, the function and mechanism of circ_0038467 in pneumonia remain elusive.

Methods

Cell viability and apoptosis were determined using the Cell Counting Kit‐8 (CCK‐8) assay and flow cytometry, respectively. The levels of interleukin 6 (IL‐6), IL‐8 and IL‐1β were detected by enzyme‐linked immunosorbent assay (ELISA). Western blot analysis was performed to assess the expression of related proteins. Circ_0038467 was characterized by Ribonuclease R (RNase) digestion and subcellular localization assays. The levels of circ_0038467 and miR‐338‐3p were evaluated by quantitative real‐time polymerase chain reaction (qRT‐PCR). The direct interaction between circ_0038467 and miR‐338‐3p was validated by the dual‐luciferase reporter and RNA immunoprecipitation (RIP) assays.

Results

Our data indicated that lipopolysaccharide (LPS) induced an inflammatory injury in 16HBE cells by repressing cell viability and enhancing cell apoptosis and proinflammatory cytokines production. Circ_0038467 was upregulated and miR‐338‐3p was downregulated in LPS‐treated 16HBE cells. Circ_0038467 knockdown or miR‐338‐3p overexpression attenuated LPS‐induced 16HBE cell inflammatory injury. Moreover, circ_0038467 acted as a sponge of miR‐338‐3p in 16HBE cells. MiR‐338‐3p mediated the alleviated effect of circ_0038467 knockdown on LPS‐induced 16HBE cell inflammatory injury. Additionally, the Janus kinase/ signal transducer and activator of transcription 3 (JAK/STAT3) signaling pathway was involved in the circ_0038467/miR‐338‐3p axis‐mediated regulation in LPS‐induced 16HBE cell inflammatory injury.

Conclusions

The current work had led to the identification of circ_0038467 knockdown that alleviated LPS‐induced inflammatory injury in 16HBE cells at least partly through sponging miR‐338‐3p and regulating JAK/STAT3 pathway, highlighting novel molecular targets for the treatment of pneumonia.

Review-Current Concepts in Inflammatory Skin Diseases Evolved by Transcriptome Analysis: In-Depth Analysis of Atopic Dermatitis and Psoriasis

During the last decades, high-throughput assessment of gene expression in patient tissues using microarray technology or RNA-Seq took center stage in clinical research. Insights into the diversity and frequency of transcripts in healthy and diseased conditions provide valuable information on the cellular status in the respective tissues. Growing with the technique, the bioinformatic analysis toolkit reveals biologically relevant pathways which assist in understanding basic pathophysiological mechanisms. Conventional classification systems of inflammatory skin diseases rely on descriptive assessments by pathologists. In contrast to this, molecular profiling may uncover previously unknown disease classifying features. Thereby, treatments and prognostics of patients may be improved. Furthermore, disease models in basic research in comparison to the human disease can be directly validated. The aim of this article is not only to provide the reader with information on the opportunities of these techniques, but to outline potential pitfalls and technical limitations as well. Major published findings are briefly discussed to provide a broad overview on the current findings in transcriptomics in inflammatory skin diseases.

Analysis of Potential Genes and Pathways Involved in the Pathogenesis of Acne by Bioinformatics

Acne is the eighth most frequent disease worldwide. Inflammatory response runs through all stages of acne. It is complicated and is involved in innate and adaptive immunity. This study aimed to explore the candidate genes and their relative signaling pathways in inflammatory acne using data mining analysis. Microarray data GSE6475 and GSE53795, including 18 acne lesion tissues and 18 matched normal skin tissues, were obtained. Differentially expressed genes (DEGs) were filtered and subjected to functional and pathway enrichment analyses. Protein-protein interaction (PPI) network and module analyses were also performed based on the DEGs. In this work, 154 common DEGs, including 145 upregulated and 9 downregulated, were obtained from two microarray profiles. Gene Ontology and pathway enrichment of DEGs were clustered using significant enrichment analysis. A PPI network containing 110 nodes/DEGs was constructed, and 31 hub genes were obtained. Four modules in the PPI network, which mainly participated in chemokine signaling pathway, cytokine-cytokine receptor interaction, and Fc gamma R-mediated phagocytosis, were extracted. In conclusion, aberrant DEGs and pathways involved in acne pathogenesis were identified using bioinformatic analysis. The DEGs included FPR2, ITGB2, CXCL8, C3AR1, CXCL1, FCER1G, LILRB2, PTPRC, SAA1, CCR2, ICAM1, and FPR1, and the pathways included chemokine signaling pathway, cytokine-cytokine receptor interaction, and Fc gamma R-mediated phagocytosis. This study could serve as a basis for further understanding the pathogenesis and potential therapeutic targets of inflammatory acne.

Circular RNA expression profile analysis of severe acne by RNA-Seq and bioinformatics

BACKGROUND

Acne is a common chronic skin disease with a multifactorial aetiology and pathogenesis. Recently, circular RNAs (circRNAs) have been identified as a key factor in regulating gene expression through circRNA-miRNA-mRNA networks in many biological processes and human diseases. However, the circRNAs expression in patients with acne is still unknown.

OBJECTIVE

To investigate circRNA expression profile in severe acne.

METHODS

The expression profile of circRNAs in three paired lesional skin and adjacent non-lesional skin in severe acne was detected by high-throughput RNA sequencing technology and bioinformatics analysis. The candidate circRNAs were validated by PCR, Sanger sequencing and qRT-PCR in the separate group (n = 4). The circRNA-miRNA-mRNA interaction networks were predicted.

RESULTS

A total of 538 circRNAs including 271 up- and 267 downregulated circRNAs were differentially expressed in lesional skin compared with adjacent non-lesional skin in severe acne. Gene Ontology and KEGG pathway enrichment analyses revealed that the aberrantly expressed circRNAs were primarily involved in inflammatory, metabolism and immune responses. Five candidate circRNAs (circRNA_0084927, circRNA_0001073, circRNA_0005941, circRNA_0086376 and circRNA_0018168) were validated to have significant decrease in severe acne by PCR, Sanger sequencing and qRT-PCR, in agreement with the results from RNA-Seq data analysis. The five identified circRNAs were predicted to interact with 213 miRNAs and regulated target gene expression.

CONCLUSION

This study firstly showed that circRNAs were differentially expressed in severe acne and suggested that circRNAs could be used as a potential biomarker for the drug targets of acne.