Search

Elevated hepatic gluconeogenesis is a major contributor of fasting hyperglycemia in diabetes. MicroRNAs (miRNAs) are tightly linked to glucose metabolism, but their role in hepatic gluconeogenesis remains largely unkown. In this current study, miR-34a-5p expression was significantly increased in liver tissues of db/db mice. Overexpression of miR-34a-5p promoted hepatic glucose production in mouse primary hepatocytes with increased expressions of gluconeogenic genes while miR-34a-5p inhibition displayed a contrary action. MiR-34a-5p overexpression in mouse primary hepatocytes repressed SIRT1 expression. SIRT1 inhibition by EX527 blocked phosphoenolpyruvate carboxykinase (PEPCK) protein degradation and enhanced hepatic gluconeogenesis. Treatment of A485 (a CBP/p300 inhibitor) decreased miR-34a-5p and PEPCK expressions in the livers of db/db mice, but elevated SIRT1 protein expression. In mouse primary hepatocytes, A485 exhibited a similar result. Overexpression of miR-34a-5p attenuated A485-inhibited gluconeogenic gene expressions and A485-induced SIRT1 protein expression. Finally, after miR-34a-5p was inhibited in the livers of db/db mice, hepatic glucose production and gluconeogenic gene expressions were markedly lowered. Our findings highlight a critical role of miR-34a-5p in the regulation of hepatic gluconeogenesis and miR-34a-5p may be a potential target in the treatment of type 2 diabetes. [ABSTRACT FROM AUTHOR]

MicroRNAs are a family of small noncoding RNAs, regulating gene expression at the post-transcriptional level and playing a crucial role as potential biomarkers and targets for many types of cancer. Our attention was given to electrochemical and spectral studies of miR-34a-5p, related to head and neck and also prostate cancer. Voltammetric experiments on a hanging mercury drop electrode and circular dichroic spectroscopic experiments in buffer solutions were performed in the range of pH from 3 to 6 and from 3 to 8, respectively. The miRNA and its DNA sequential analogues (miDNA) provided interesting and significantly different results. A comparison of miRNA and both miDNA (U) and (T) showed the effect of substitution of ribose to deoxyribose, and structural diversity of nucleic acids was confirmed by both electrochemical and spectral methods. It emerged that a single substitution of ribose to deoxyribose (equivalent to miRNA→miDNA (U)) leads on to the formation of a second guanine oxidation peak, and an RNA molecule in contrast to DNA analogues offers circular dichroic spectra of higher variability (indicating more terminal structures) and a more observable dependence on pH in the range of 3-6. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Aflatoxin B1 (AFB1) is a well-known human hepatotoxicant and genotoxicant. Recent studies demonstrated that aberrant miRNA expression patterns were correlated with the cellular and genetic lesions induced by chemicals. To explore the role of miRNAs in AFB1-induced hepatotoxicity and genotoxicity, we examined alterations in miRNA expression patterns in F334 rat livers after exposure to 100 μg/kg or 200 μg/kg AFB1 for 28 days. Using high-throughput sequencing, we discovered that rno-miR-34a-5p, rno-miR-200b-3p, and rno-miR-429 were up-regulated and that rno-miR-130a-3p was down-regulated in liver tissue from rats that received 200 μg/kg of AFB1; this finding was validated by real-time PCR. AFB1 treatment resulted in the upregulation of rno-miR-34a-5p and rno-miR-200b-3p in the rat H-4-II-E cell line similar to our in vivo observations. Moreover, rno-miR-34a-5p was transcriptionally elevated via p53 activation after AFB1 exposure. Upregulation of rno-miR-34a-5p suppressed the expression of the cell cycle-related genes CCND1, CCNE2 and MET and led to cell cycle arrest in the G0-G1 phase. The CBMN assay indicated that inhibition of rno-miR-34a-5p and p53 expression aggravated the DNA damage induced by AFB1, which might be associated with shortening of the DNA damage repair period. Circulating miR-34a-5p in rat sera preceded a significant increase in ALT activity and other miRNAs in the 100 μg/kg AFB1 group. These observations demonstrated that rno-miR-34a-5p responded sensitively to AFB1 exposure and facilitated p53 repair of DNA damage by impacting the cell cycle. Thus, circulating rno-miR-34a-5p may be a sensitive indicator for the induction of hepatic genotoxicity by AFB1 in rats. [ABSTRACT FROM AUTHOR]

Primary Myelofibrosis (PMF) is a chronic Philadelphia-negative myeloproliferative neoplasm characterized by a skewed megakaryopoiesis and an overproduction of proinflammatory and profibrotic mediators that lead to the development of bone marrow (BM) fibrosis. Since we recently uncovered the upregulation of miR-34a-5p in PMF CD34+ hematopoietic progenitor cells (HPCs), in order to elucidate its role in PMF pathogenesis here we unravelled the effects of miR-34a-5p overexpression in HPCs. We showed that enforced expression of miR-34a-5p partially constrains proliferation and favours the megakaryocyte and monocyte/macrophage commitment of HPCs. Interestingly, we identified lymphoid enhancer-binding factor 1 (LEF1) and nuclear receptor subfamily 4, group A, member 2 (NR4A2) transcripts as miR-34a-5p-targets downregulated after miR-34a-5p overexpression in HPCs as well as in PMF CD34+ cells. Remarkably, the knockdown of NR4A2 in HPCs mimicked the antiproliferative effects of miR-34a-5p overexpression, while the silencing of LEF1 phenocopied the effects of miR-34a-5p overexpression on HPCs lineage choice, by favouring the megakaryocyte and monocyte/macrophage commitment. Collectively our data unravel the role of miR-34a-5p in HPCs fate decision and suggest that the increased expression of miR-34a-5p in PMF HPCs could be important for the skewing of megakaryopoiesis and the production of monocytes, that are key players in BM fibrosis in PMF patients.

The coronary microembolization contributes to coronary microvascular dysfunction (CMD), in which miR-34a-5p may play a critical role. Ligustrazine has been reported to improve CMD. The present study was designed to discuss the role of miR-34a-5p/Sirt1 pathway in CMD and explore the underlying mechanism of ligustrazine. Coronary microembolization (CME) was induced by left ventricle injection of sodium laurate in rats. CME formation and cardiac function were examined by HE staining and hemodynamic tests to evaluate CMD. The expressions of miR-34a-5p, Sirt1 and the downstream proteins were detected by RT-qPCR and western blot. Dual-luciferase reporter (DLR) assay was performed to confirm the connection between miR-34a-5p and Sirt1. The blood markers of endothelial dysfunction, platelet activation and inflammation were examined with ELISA. Overt CME and cardiac dysfunction as well as up-regulated miR-34a-5p and down-regulated Sirt1 were observed in CME rats. Overexpressing miR-34a-5p aggravated while silencing miR-34a-5p inhibited CME formation. DLR assay confirmed that miR-34a-5p directly inhibited Sirt1 mRNA expression. Ligustrazine pretreatment suppressed miR-34a-5p and promoted Sirt1 expression, which alleviated endothelial dysfunction, inhibited platelet activation and inflammation, and in turn reduced CME. Overexpressing miR-34a-5p diminished the positive effects of ligustrazine; while after silencing miR-34a-5p, ligustrazine failed to further promote Sirt1 expression and inhibit CME formation. MiR-34a-5p contributes to CMD by inhibiting Sirt1 expression. Ligustrazine exerts endothelial-protective, anti-platelet and anti-inflammatory effects to prevent CMD via suppressing miR-34a-5p and promoting Sirt1. • MiR-34a-5p contributes to CMD via inhibiting Sirt1 expression, which is demonstrated for the first time. • MiR-34a-5p is an essential target for ligustrazine to promote Sirt1 expression. • Ligustrazine prevents CMD via suppressing miR-34a-5p and accordingly activating Sirt1/eNOS and Sirt1/NFκB pathway. [ABSTRACT FROM AUTHOR]

Background: Irritable bowel syndrome (IBS) is a known brain-gut disorder. Currently, the molecular and cellular mechanisms of IBS remain unclear. Atractylenolide-I (ATL-I) is a majorly bioactive component extracted from Rhizoma Atractylodes Macrocephalae ., Methods: Studies have revealed that ATL-I functioned as an anti-tumor drug in various cancers. However, the effects and molecular mechanisms of ATL-I on the pathological processes of colonic mucosal epithelial cells (CMECs) during IBS remain unclear. This study reports ATL-I effectively alleviated the oxidative stress-induced colonic mucosal epithelial cell dysfunction. In colonic mucosal tissues from IBS patients, we detected upregulated miR-34a-5p and suppressed glucose metabolism enzyme expressions. Under H 2 O 2 treatment which mimics in vitro oxidative stress, miR-34a-5p was induced and glucose metabolism was inhibited in the colon mucosal epithelial cell line, NCM460. Meanwhile, ATL-I treatment effectively overcame the oxidative stress-induced miR-34a- 5p expression and glucose metabolism in NCM460 cells., Result: By bioinformatics analysis, Western blot and luciferase assay, we illustrated that miR-34a-5p directly targeted the 3'UTR region of glucose metabolism key enzyme, lactate dehydrogenase-A (LDHA) in colonic mucosal epithelial cells. Rescue experiments validated that miR-34a-5p inhibited glucose metabolism by targeting LDHA. Finally, we demonstrated that ATL-I treatment reversed the miR-34a-5p-inhibited glucose metabolism and -exacerbated colonic mucosal epithelial cell dysfunction under oxidative stress by modulating the miR-34a-5p-LDHA pathway., Conclusion: Summarily, our study reports the roles and mechanisms of ATL-I in the oxidative stress-induced colonic mucosal epithelial cell dysfunction during IBS through regulating the miR-34a-5p-LDHA-glucose metabolism axis., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Humans are often exposed to complex mixtures of environmental pollutants over long periods of time. It is reported that Dibutyl phthalate (DBP) and benzo[a]pyrene (BaP) are typical environmental pollutants, which are associated with liver injury. Nevertheless, little is known about the effects of DBP and BaP combined exposure on liver. In the current study, rats were exposed to DBP alone (50, or 250 mg/kg), BaP alone (1, or 5 mg/kg), or DBP and BaP (50 + 1, or 250 + 5 mg/kg) for ninety days. More serious liver damage, including abnormal liver function, infiltration of inflammatory cells and disturbed secretion of inflammatory factors, were observed in long-term co-exposure to DBP and BaP group relative to those in single exposure group. Our data showed that long-term co-exposure to DBP and BaP induces macrophages to polarize toward M1 and inhibits polarization of M2 macrophages. Long-term co-exposure to DBP and BaP downregulated miR-34a-5p level and upregulated Notch signaling. These results indicated that imbalance in macrophages M1/M2 polarization mediated by activation of Notch signaling due to reduced miR-34a-5p level may contribute to additive effects on disorder of inflammatory factors secretion and subsequent liver injury following long-term DBP and BaP co-exposure. [Display omitted] • Long-term co-exposure to DBP and BaP exacerbated liver inflammatory injury. • Imbalance in macrophage polarization regulated by Notch signaling is involved in the liver injury. • MiR-34a-5p acts as a negative regulator targeting Notch signaling in DBP and BaP-induced liver injury. [ABSTRACT FROM AUTHOR]

Objective: To explore the effect and mechanisms of a traditional Chinese quadri-combination therapy [Bushen, Yiqi, Lixue and Yangtai (BYLY)] in treating recurrent spontaneous abortion (RSA). Methods: A clinical trial was conducted to study the effect of BYLY on RSA. Pharmacological network analysis and UPLC-Q/TOF-mass spectrometry (MS) were applied to investigate the key active component in BYLY and potential targets. Cellular experiments based on former results were performed to examine the mechanism of BYLY in the treatment of RSA. Results: Four hundred and eighty participants enrolled in the clinical trial. The results showed that, compared with the use of BYLY or duphaston alone, a combination of duphaston and BYLY could decrease the early abortion rate in RSA ( p < 0.001). Network pharmacological analysis indicated that BYLY contained 132 active components and 146 core targets, and the quercetin maybe the key effective component. In vitro experiments found that pretreatment of quercetin at the correct concentration (2 μM) prevented hypoxia-induced viability and proliferation reduction, and apoptosis and mitochondrial dysfunction. Furthermore, quercetin could modulate mitochondrial fission/fusion balance in trophoblasts, and specifically decrease the expression of Drp1 by regulating miR-34a-5p. Conclusion: BYLY could improve pregnancy outcomes of RSA, based on multi-components and multi-targets. The protective effect of quercetin on trophoblasts, through decreasing Drp1 expression via regulating miR-34a-5p, might be one possible effective mechanism., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhou, Li, Pan, Wang, Qi, Sun, Li and Wang.)

Purpose: Long non-coding RNA (lncRNA) XIST has been shown to be involved in the immune escape of breast cancer, but it is unclear whether it is involved in the immune escape of lung cancer, so it will be discussed in this study., Methods: XIST and miR-34a-5p expression in lung cancer tissues and cells were detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The targeting relationship between miR-34a-5p and XIST/programmed cell death receptor ligand 1 (PDL1) was predicted by bioinformatics website and verified by dual-luciferase report experiment. After co-transfection with XIST specific short hairpin RNA (sh-XIST) and miR-34a-5p inhibitors, the changes in PDL1 expression, and cell biological behavior were detected by qRT-PCR, cell counting kit 8, flow cytometry, and Transwell experiments. Similarly, after co-transfection of PDL1 specific small interfering RNA (siPDL1) and miR-34a-5p inhibitors, the changes in cell biological behavior were detected again. After CD8+ T cells were co-cultured with lung cancer cells transfected with sh-XIST and miR-34a-5p inhibitors, the expression of cytokines and immunosuppressive molecules was detected by western blot and enzyme-linked immunosorbent assay (ELISA)., Results: XIST was up-regulated in lung cancer tissues, while miR-34a-5p was the opposite. XIST up-regulated the expression of PDL1 by targeting miR-34a-5p, thereby affecting the viability, apoptosis, migration, and invasion of lung cancer cells. In the co-culture system, XIST targeted miR-34a-5p to inhibit cytokines secretion and promote the expression of immunosuppressive molecules., Conclusions: XIST/miR-34a-5p/PDL1 axis was involved in the malignant biological behavior of lung cancer cells and the immune function of CD8 + T cells.

miR-34a-5p has been reported to be upregulated and function as an oncogene in papillary thyroid cancer (PTC). Crocin, the major chemical constituent of saffron, has been demonstrated to possess anti-tumorigenic activity and decrease miR-34a-5p expression. Thus we hypothesized that crocin exerted anti-PCT effect by downregulating miR-34a-5p. Herein, the hypothetical mechanism underlying the anti-PCT effect of crocin was explored. Cell viability and apoptosis were assessed by CCK-8 and TUNEL assays, respectively. Reactive oxygen species (ROS) level, caspase-3 activity, and LDH release were measured using corresponding commercially available assay kits. Expression of miR-34a-5p and protein tyrosine phosphatase nonreceptor type 4 (PTPN4) was analyzed using qRT-PCR and western blot analyses. Interaction between miR-34a-5p and targets were predicted by Targetscan, starbase, miRDB, microT-CDS, and miRWalk and validated using luciferase reporter assay. Results showed that crocin inhibited the viability and miR-34a-5p expression in papillary thyroid cancer (PTC) cells in a dose-dependent manner. The Venn diagram showed that 10 overlapped targets of miR-34a-5p were identified, among which PTPN4 was the most significantly downregulated target gene in thyroid cancer tissues based on the heat map and bar plot from GSE33630 analysis. Luciferase reporter assay validated the direct interaction between miR-34a-5p and PTPN4. Crocin upregulated PTPN4 by decreasing miR-34a-5p expression in PTC cells. Crocin promoted apoptosis and increased caspase-3 activity and LDH release, which were reversed by ROS scavenger N -acetyl-L-cysteine (NAC), miR-34a overexpression, and PTPN4 silencing. To conclude, crocin promoted ROS-mediated apoptosis of PTC cells by modulating the miR-34a-5p/PTPN4 axis. • Crocin inhibits cell viability and miR-34a-5p expression. • Crocin promotes ROS-dependent apoptosis in PTC cells by regulating miR-34a-5p. • PTPN4 is identified as a target of miR-34a-5p. • miR-34a-5p/PTPN4 axis is responsible for anti-thyroid cancer effect of crocin. [ABSTRACT FROM AUTHOR]

SIRT1 is tightly associated with the progression of prostate cancer while the role of Hsa-miR-34a-5p in SIRT1-mediated prostate cancer is not fully understood. We have thoroughly mined the data from two databases, namely the Lipidemia and the cancer genome atlas (TCGA) and found that SIRT1 was highly expressed in human carcinoma tissues as compared to normal tissues, and patients with high SIRT1 expression level had a shorter survival time. The online tool "Gene-RADAR" was applied to investigate the interaction among SIRT1, the TP53 gene and miR-34a-5p. We found that SIRT1 was up-regulated in cancer tissues from patients diagnosed with prostate and castration-resistant prostate cancer when compared to healthy controls. Pearson analysis indicated a positive correlation between SIRT1 and miR-34a-5p, while data mining on the TargetScan database predicted the binding site between the two. An apoptosis assay of prostate cancer cells (PRAD) confirmed that the overexpression of miR-34a-5p inhibited paclitaxel-induced apoptosis and promoted cell proliferation. Cell cycle analysis verified that miR-34a-5p overexpression blocked PRAD cells in the G2/S phase of the cell cycle. Moreover, the Western blotting (WB) and quantitative PCR (qPCR) assays demonstrated that the overexpression of miR-34a-5p induced down-regulation of the SIRT-related proteins HIF2α and PGC1α, while on the contrary, it up-regulated the expression of two tumour suppressor genes, TP53 and VEGF. In conclusion, we have shown that miR-34a-5p is involved in the oncogenesis of PRAD cells via the SIRT1/TP53 axis., Competing Interests: None., (AJTR Copyright © 2022.)

Osteoporosis occurs due to a dysregulation in bone remodeling, a process requiring both bone-forming osteoblasts and bone-resorbing osteoclasts. Current leading osteoporosis therapies suppress osteoclast-mediated bone resorption but show limited therapeutic effects because osteoblast-mediated bone formation decreases concurrently. We developed a gene therapy strategy for osteoporosis that simultaneously promotes bone formation and suppresses bone resorption by targeting two microRNAs (miRNAs)-miR-214-3p and miR-34a-5p. We modulated the expression of these miRNAs using systemically delivered recombinant adeno-associated viral (rAAV) vectors targeting the bone. rAAV-mediated overexpression of miR-214-3p or inhibition of miR-34a-5p in the skeleton resulted in bone loss in adult mice, resembling osteoporotic bones. Conversely, rAAV-mediated inhibition of miR-214-3p or overexpression of miR-34a-5p reversed bone loss in mouse models for postmenopausal and senile osteoporosis by increasing osteoblast-mediated bone formation and decreasing osteoclast-mediated bone resorption. Notably, these mice did not show any apparent pathological phenotypes in non-skeletal tissues. Mechanistically, inhibiting miR-214-3p upregulated activating transcription factor 4 in osteoblasts and phatase and tensin homolog in osteoclasts, while overexpressing miR-34a-5p downregulated Notch1 in osteoblasts and TGF-β-induced factor homeobox 2 in osteoclasts. In summary, bone-targeting rAAV-mediated regulation of miR-214-3p or miR-34a-5p is a promising new approach to treat osteoporosis, while limiting adverse effects in non-skeletal tissues., Competing Interests: G.G. and J.-H.S. are scientific co-founders of AAVAA Therapeutics and hold equity in this company. G.G. is also a scientific co-founder of Voyager Therapeutics and Aspa Therapeutics and holds equity in these companies. G.G. is an inventor on patents with potential royalties licensed to Voyager Therapeutics, Aspa Therapeutics Inc., and other biopharmaceutical companies., (© 2022 The Author(s).)

Objectives: This study aims to explore the mechanism by which long non-coding ribonucleic acids (lncRNA) X-inactive specific transcript (XIST) affects the progression of adjuvant-induced arthritis (AIA)., Materials and Methods: Freund's complete adjuvant was used to induce arthritis in rats. The polyarthritis, spleen and thymus indexes were calculated to evaluate AIA. Hematoxylin-eosin (H&E) staining was used to reveal the pathological changes in the synovium of AIA rats. Enzyme-linked immunosorbent assay (ELISA) was performed to detect the expression of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6 and IL-8 in the synovial fluid of AIA rats. The cell continuing kit (CCK)-8, flow cytometry, and Transwell assays were used to assess the proliferation, apoptosis, migration and invasion of transfected fibroblast-like synoviocytes (FLS) isolated from AIA rats (AIA-FLS). Dual-luciferase reporter assay was performed to verify the binding sites between XIST and miR-34b-5p or between YY1 mRNA and miR-34b-5p., Results: The XIST and YY1 were highly expressed, and miR-34a-5p was lowly expressed in the synovium of AIA rats and in AIA-FLS. Silencing of XIST impaired the function of AIA-FLS in vitro and inhibited the progression of AIA in vivo . The XIST promoted the expression of YY1 by competitively binding to miR-34a-5p. Inhibition of miR-34a-5p strengthened the function of AIA-FLS by upregulating XIST and YY1., Conclusion: The XIST controls the function of AIA-FLS and may promote the progression of rheumatoid arthritis via the miR-34a-5p/YY1 axis., Competing Interests: Conflict of Interest: The authors declared no conflicts of interest with respect to the authorship and/or publication of this article., (Copyright © 2023, Turkish League Against Rheumatism.)

Background: We aimed to investigate the effects of miR-34a-5p on c-fos regulation mediating the malignant behaviors of SH-SY5Y cells infected with Kaposi's sarcoma-associated herpesvirus (KSHV)., Methods: The KSHV-infected (SK-RG) and uninfected SH-SY5Y parent cells were compared for differentially expressed miRNAs using transcriptome sequencing. Then miR-34a-5p was upregulated in SK-RG cells by the miRNA mimics transfection. Cell proliferation ability was determined by MTT and plate clone assays. The cell cycle was assessed by flow cytometry analysis, and CDK4, CDK6, cyclin D1 levels were determined by Western blot analysis. The migration behavior was detected by wound healing and transwell assays. The protein levels of MMP2 and MMP9 were measured by Western blot analysis. The regulation of c-fos by miR-34a-5p was detected by the dual-luciferase reporter gene assay. Rescue assays were carried out by upregulating c-fos in miR-34a-5p-overexpressing SK-RG cells. KSHV DNA copy numbers and relative virus gene expressions were detected. Xenograft tumor experiments and immunohistochemistry assays were further used to detect the effects of miR-34a-5p., Results: miR-34a-5p was lower in SK-RG cells. Restoration of miR-34a-5p decreased cell proliferation and migration, leading to a G1 cell cycle arrest and down-regulation of CDK4/6, cyclin D1, MMP2, MMP9. KSHV copy number and expression of virus gene including latency-associated nuclear antigen (LANA), replication and transcription activator (RTA), open reading frame (K8.1), and KSHV G protein-coupled receptor (v-GPCR) were also reduced. Furthermore, c-fos is the target of miR-34a-5p, while enhanced c-fos weakened cellular behaviors of miR-34a-5p-overexpressing cells. Xenograft experiments and immunohistochemistry assays showed that miR-34a-5p inhibited tumor growth and virus gene expression., Conclusion: Upregulated miR-34a-5p in KSHV-infected SH-SY5Y cells suppressed cell proliferation and migration through down-regulating c-fos. miR-34a-5p was a candidate molecular drug for KSHV-infected neuronal cells., Competing Interests: The authors declare that they have no competing interests., (© 2022 Wu et al.)

Neuroblastoma (NB) is a childhood cancer that often occurs in the sympathetic nervous system. Previous reports showed that long non-coding RNAs (lncRNAs) could affect the progress of NB, but the mechanism is still indistinct. In this study, we unfolded the roles of LINC01296 in NB tissues and cells. The level of LINC01296, microRNA-584-5p (miR-584-5p), miR-34a-5p and mRNA of tripartite motif-containing 59 (TRIM59) were indicated by quantitative real-time polymerase chain reaction (qRT-PCR) in NB tissues. The capacities of NB cells were validated by MTT assay, Edu assay, transwell assay and flow cytometry analysis. The interplay between miR-584-5p/miR-34a-5p and LINC01296 or TRIM59 were detected by dual-luciferase reporter assay. Finally, the in vivo experiment was implemented to verify the effect of LINC01296 in vivo. The level of LINC01296 and TRIM59 were increased, whereas miR-584-5p and miR-34a-5p levels were reduced in NB tissues in contrast to that in normal tissues. For functional analysis, LINC01296 deficiency inhibited the cell vitality, cell proliferation, migration and invasion in NB cells, whereas promoted cell apoptosis. Moreover, miR-584-5p and miR-34a-5p were validated to act as a tumor repressive effect in NB cells by restraining TRIM59. The results also showed that LINC01296 could regulate the development of NB. In mechanism, LINC01296 acted as a miR-584-5p and miR-34a-5p sponge to modulate TRIM59 expression. In addition, LINC01296 knockdown also attenuated tumor growth in vivo. LINC01296 promotes the progression of NB by increasing TRIM59 expression via regulating miR-584-5p and miR-34a-5p, which also offered an underlying targeted therapy for NB treatment., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Circular RNAs (circRNAs) are crucial for the pathogenesis of human diseases, including osteoarthritis (OA). Here, we set to elucidate the biological action of circ-LRP1B in OA pathogenesis. Human C28/I2 chondrocytes were stimulated by lipopolysaccharide (LPS). Circ-LRP1B, nuclear factor, erythroid 2 like 1 (NRF1) and microRNA (miR)-34a-5p were quantified by quantitative real-time PCR (qRT-PCR) or immunoblotting. Cell viability, proliferation, and apoptosis abilities were gauged by MTT, 5-Ethynyl-2'-Deoxyuridine (EdU) staining, and flow cytometry assays, respectively. Direct relationship between miR-34a-5p and circ-LRP1B or NRF1 was validated by RNA pull-down and dual-luciferase reporter assays. Circ-LRP1B was found to be underexpressed in OA cartilage and LPS-stimulated C28/I2 chondrocytes. Enforced expression of circ-LRP1B promoted cell proliferation, and repressed apoptosis and oxidative stress, as well as impacted OA-specific hallmarks expression of LPS-stimulated C28/I2 cells. NRF1 was identified as a downstream effector of circ-LRP1B function. Moreover, NRF1 was identified as a miR-34a-5p target in LPS-stimulated C28/I2 cells. Circ-LRP1B acted as a competing endogenous RNA (ceRNA) for miR-34a-5p to involve the post-transcriptional regulation of NRF1 expression. Furthermore, the effects of circ-LRP1B overexpression partly depended on the reduction of available miR-34a-5p. These findings demonstrate that circ-LRP1B functions as a ceRNA to regulate the proliferation, apoptosis and oxidative stress of LPS-stimulated human C28/I2 chondrocytes by miR-34a-5p/NRF1 network., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Photodynamic therapy (PDT) provides apparent survival benefits for unresectable cholangiocarcinoma patients. the insufficient sensitivity of cancer cell to PDT treatment limits the clinical application. In this study, according to the GEO datasets, WNT7B expression was decreased by PDT treatment in cholangiocarcinoma samples. In cholangiocarcinoma cells, PDT treatment inhibited Wnt signaling, suppressed cell viability, and enhanced cell apoptosis. Within cholangiocarcinoma cells, PDT treatment induced p53 and miR-34a-5p expression. Under PDT treatment, p53 knockdown downregulated miR-34a-5p expression, whereas the inhibition effect of p53 knockdown on miR-34a-5p could be partially attenuated by agomir-34a-5p. p53 knockdown enhanced cell viability and suppressed cell apoptosis, whereas miR-34a-5p overexpression exerted opposite effects; miR-34a-5p overexpression partially attenuated p53 knockdown effects on PDT-treated cholangiocarcinoma cells. miR-34a-5p directly targeted WNT7B and inhibited WNT7B expression. Under PDT treatment, WNT7B knockdown inhibited the Wnt signaling and cell viability, and promoted cell apoptosis, while miR-34a-5p suppression showed the opposite trends; WNT7B knockdown partially attenuated miR-34a-5p inhibition effects on PDT-treated cholangiocarcinoma cells. In conclusion, PDT treatment induces p53-induced miR-34a transactivation to inhibit cholangiocarcinoma cell proliferation; the miR-34a-5p/WNT7B axis and Wnt signaling are involved., Competing Interests: Declaration of competing interest None., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Long non-coding RNA LINC01106 is an lncRNA aberrantly expressed in gastric cancer (GC). However, the accurate function remains unclear. The objective of this investigation is to explore detailed regulatory mechanism of lncRNA LINC01106 in GC. The expression of lncRNA LINC01106, MYCN, and miR-34a-5p was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability was examined using MTT assay. Migratory and invasive abilities of GC cells were evaluated by transwell assay. The targeting relation among lncRNA LINC01106, MYCN, and miR-34a-5p was tested by dual-luciferase reporter (DLR) assay. Relative protein expression of MYCN was assessed via western blot. Besides, a xenograft mouse model was established to assess the role of LINC01106 in GC in vivo. LncRNA LINC01106 and MYCN expression were boosted and miR-34a-5p expression was reduced in GC cells and tissues compared to their controls. Functionally, decreased lncRNA LINC01106 or increased miR-34a-5p restrained GC cells in viability, invasion, and migration in vitro. LINC01106 down-regulation suppressed tumor growth of mice in vivo. In terms of mechanism, lncRNA LINC01106 directly targeted miR-34a-5p and was inversely correlated with miR-34a-5p. MYCN was targeted by miR-34a-5p and was inversely correlated with miR-34a-5p. There was a positive correlation between LINC01106 and MYCN. LINC01106 knockdown led to the suppression of cell invasion, migration, and viability, whereas these effects caused by LINC01106 knockdown were reversed by miR-34a-5p down-regulation or MYCN up-regulation in GC cells. Silencing of lncRNA LINC01106 attenuated cell viability, invasion, and migration by sponging miR-34a-5p to target MYCN in GC., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Early life radiation exposure causes abnormal brain development, leading to adult depression. However, few studies have been conducted to explore pre- or post-natal irradiation-induced depression-related neuropathological changes. Relevant molecular mechanisms are also poorly understood. We induced adult depression by irradiation of mice at postnatal day 3 (P3) to reveal hippocampal neuropathological changes and investigate their molecular mechanism, focusing on MicroRNA (miR) and its target mRNA and protein. P3 mice were irradiated by γ-rays with 5Gy, and euthanized at 1, 7 and 120 days after irradiation. A behavioral test was conducted before the animals were euthanized at 120 days after irradiation. The animal brains were used for different studies including immunohistochemistry, CAP-miRSeq, Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) and western blotting. The interaction of miR-34a-5p and its target T-cell intracytoplasmic antigen-1 (Tia1) was confirmed by luciferase reporter assay. Overexpression of Tia1 in a neural stem cell (NSC) model was used to further validate findings from the mouse model. Irradiation with 5 Gy at P3 induced depression in adult mice. Animal hippocampal pathological changes included hypoplasia of the infrapyramidal blade of the stratum granulosum, aberrant and impaired cell division, and neurogenesis in the dentate gyrus. At the molecular level, upregulation of miR-34a-5p and downregulation of Tia1 mRNA were observed in both animal and neural stem cell models. The luciferase reporter assay and gene transfection studies further confirmed a direct interaction between miR-34a-5p and Tia1. Our results indicate that the early life γ-radiation-activated miR-34a-5p/Tia1 pathway is involved in the pathogenesis of adult depression. This novel finding may provide a new therapeutic target by inhibiting the miR-34a-5p/Tia1 pathway to prevent radiation-induced pathogenesis of depression. [ABSTRACT FROM AUTHOR]

Macrophage polarization and infiltration to the tumor microenvironment (TME) is a critical determining factor for tumor progression. Macrophages are polarized into two states—M1 (pro-inflammatory, anti-tumorigenic and stimulated by LPS or IFN-γ) and M2 (anti-inflammatory pro-tumorigenic and stimulated by IL-4) phenotypes. Specifically, M2 macrophages enhance tumor cell growth and survival. Recent evidences suggest the pivotal role of microRNAs in macrophage polarization during the development of Non-small cell lung cancer (NSCLC), thus proposing a new therapeutic option to target lung cancer. In silico analysis determined cogent upregulation of KLF4, downregulation of IL-1β and miR-34a-5p in NSCLC tissues, consequently worsening the overall survival of NSCLC patients. We observed a significant association of KLF4 with macrophage infiltration and polarization in NSCLC. We found that KLF4 is critically implicated in M2 polarization of macrophages, which, in turn, promotes tumorigenesis. KLF4 expression correlated with miR-34a-5p and IL-1β in a feed-forward loop (FFL), both of which are implicated in immune regulation. Mechanistic overexpression of miR-34a-5p in macrophages (IL-4 stimulated) inhibits KLF4, along with downregulation of ARG1, REL-1MB (M2 macrophage specific markers), and upregulation of IL-1β, IL-6, (M1 macrophage specific markers), demonstrating macrophage polarization switch from M2 to M1 phenotype. Moreover, co-culture of these macrophages with NSCLC cells reduces their proliferation, wound healing, clonogenic capacity and enhanced NO-mediated apoptosis. Further, transfection of miR-34a-5p in NSCLC cells, also degrades KLF4, but enhances the expression of KLF4 regulated genes—IL-1β, IL-6 (pro-inflammatory mediators), which is further enhanced upon co-culture with IL-4 stimulated macrophages. Additionally, we observed a significant increase in i-NOS/NO content upon co-culture, suggesting polarization reversion of macrophages from M2 to M1, and eventually leading to anti-tumor effects. Our findings thus show a significant role of KLF4 in tumorigenesis and TAM polarization of NSCLC. However, miR-34a-5p mediated targeting of these molecular networks will provide a better therapeutic intervention for NSCLC. [ABSTRACT FROM AUTHOR]

In the current study, the effects of 7-BIO as a specific GSK3β inhibitor was examined on cell survival and expression of miR-29a-3p and miR-34a-5p in neurotoxin MPP + treated SH-SY5Y cells. Our findings revealed that while co-treatment of the cells with 7-BIO and MPP + did not alter the toxicity induced by MPP + , pretreatment with 3.5 μM 7-BIO for 6 h increased the survival of the 2 mM MPP + treated cells. Also, qRT-PCR analysis of gene expression showed that while miR-29a-3p was unchanged in cells treated with either 2 mM MPP + or 3.5 μM 7-BIO alone, miR-34a-5p was increased by MPP + but decreased by 7-BIO. Pretreatment with 3.5 μM 7-BIO prior to MPP + however, increased miR-29a-3p but decreased miR-34a-5p induced by MPP + . We therefore suggest that 7-BIO inhibition of GSK3β alleviates the MPP + induced neurotoxicity by regulating miR-29a-3p and miR-34a-5p expressions in Parkinson's disease model SH-SY5Y cells., Competing Interests: There is no conflict of interest between the authors., (© 2022 The Authors.)

Dexmedetomidine (DEX) protects against acute stress-induced liver injury, but what's less clear lies in the specific mechanism. To elucidate the specific mechanism underlying DEX on acute stress-induced liver injury, an in vivo model was constructed on rats with acute stress-induced liver injury by 15 min of exhaustive swimming and 3 hr of immobilization. DEX (30 μg/kg) or miR-34a-5p agomir was injected into model rats. Open field test was used to verify the establishment of the model. Liver injury was observed by hematoxylin-eosin (H&E) staining. Contents of norepinephrine (NE), alanine aminotransfease (ALT) and aspartate aminotransferase (AST) in serum of rats were detected by enzyme-linked immunosorbent assay (ELISA) and those of oxidative stress markers (reactive oxygen species (ROS), Malondialdehyde (MDA), Glutathione (GSH), Superoxide Dismutase (SOD) and Glutathione Peroxidase (GPX)) were measured using commercial kits. Apoptosis of hepatocytes was detected by Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. Western blot was performed to detect the expressions of SOD2, COX-2, cytochrome C, Cleaved caspase 3, Bax, Bcl-2, P-JNK, JNK, P-p38, p38 and c-AMP, p-PKA and PKA in liver tissues. As a result, liver injury in model rat was alleviated by DEX. DEX attenuated the increase in the levels of NE, ALT, AST, MDA, ROS, apoptosis, SOD2, COX-2, Cytochrome C, cleaved caspase 3, Bax, and P-JNK, P-p38, c-AMP, P-PKA and miR-34a-5p, and the decrease in the levels of SOD, GPX, GSH and Bcl-2 in model rats. Furthermore, miR-34a-5p overexpression could partly reverse the effects of DEX. Collectively, DEX could alleviate acute stress-induced liver injury through ROS/JNK/p38 signaling pathway via downregulation of miR-34a-5p.

Cadmium (Cd) is a potent neurotoxic metal present in the environment and food. In this study, CdCl 2 (2 or 4 μM) induced cytotoxicity and neurotoxicity in PC12 cells, causing decreases in cell viability and NEP protein expression and increase in p-tau protein expression. For the first time, CdCl 2 -initiated injury was found to result from the induction of not only apoptosis but also ferroptosis, as evidenced by the increased iron content, ROS production, and mitochondrial membrane potential along with changes in the expressions of iron death-related genes (FTH1, GPX4, ASCL4, PTGS2, and NOX1) and levels of caspase9, Bax, and Bcl-2 proteins. The molecular mechanisms leading to apoptosis and ferroptosis at least included the participation of the miR-34a-5p/Sirt1 axis, in which miR-34a-5p promoted CdCl 2 -induced neurotoxicity through targeting Sirt1. Knocking out miR-34a-5p attenuated CdCl 2 -induced damage of PC12 cells, cytotoxicity and neurotoxicity. This research provides the underlying molecular mechanisms of CdCl 2 -induced damage and asserts the role of miRNAs as critical regulators., (© 2021 Wiley Periodicals LLC.)

Objective: To determine the role of quercetin in non-small cell lung carcinoma (NSCLC) and the biological outcomes using transfection experiments., Materials and Methods: Real-time reverse transcription-PCR and data collection were performed to determine lncRNA and miRNA levels. Transwell assay was performed to assess the invasion ability of cells. Apoptosis of cells digested with trypsin was determined using the Annexin V-FITC kit. Luciferase activity was determined using the luciferase reporter gene system. Cell viability was tested using the Cell Counting Kit-8 assay. A xenograft mouse model was established to investigate the effects of quercetin on tumor growth., Results: The expression levels of the long non-coding RNA (lncRNA) small nucleolar RNA host gene 7 (SNHG7) were elevated in NSCLC cells, and the expression levels of the microRNA miR-34a-5p were decreased compared with those in normal cells. Further investigation revealed that quercetin decreased SNHG7 and elevated miR-34a-5p levels in NSCLC cells ( p  < .05). The luciferase reporter gene assay, RNA-binding protein immunoprecipitation assay, and transfection experiments revealed target-binding sequences between SNHG7 and miR-34a-5p. Overexpression of SNHG7 or miR-34a-5p inhibitor promoted NSCLC cell proliferation and accelerated tumor cell growth and metastasis. The therapeutic effect of quercetin on NSCLC cells was counteracted by co-transfection of SNHG7 mimic or miR-34a-5p inhibitor. Quercetin inhibited the survival, proliferation, migration, and invasion of NSCLC cells and enhanced their apoptosis. Using the mouse model, quercetin was shown to inhibit tumor growth., Conclusions: Quercetin inhibits the proliferation and induces apoptosis of NSCLC cells by mediating signaling via the lncRNA SNHG7/miR-34a-5p pathway.

Intracerebral hemorrhage (ICH) is the most devastating subtype of stroke with high morbidity and mortality. The previous study has confirmed the therapeutic effect of Baihui (DU20)-penetrating-Qubin (GB7) acupuncture on ICH, while the related mechanism is left to be revealed. The aim of this study was to investigate the relevant mechanisms. ICH rat models were established utilizing the autologous blood injection method and the beneficial effect was found after DU20-penetrating-GB7 acupuncture along with decreased miR-34a-5p levels in the perihemorrhagic penumbra. Inversely, upregulating miR-34a-5p expression inhibited microglia M2 polarization while accelerated M1 polarization through targeting Krüppel-like factor 4 (Klf4), and thereby diminished the protective effect of DU20-penetrating-GB7 acupuncture on ICH. The results suggested the therapeutic effect of DU20-penetrating-GB7 acupuncture on ICH might be attributed to its modulation on microglia polarization through miR-34a-5p/Klf4 signaling.

PTEN induced putative kinase 1 (PINK1)-mediated mitophagy process is tightly associated with various age-dependent diseases in mammals. The roles of miRNAs (miRNAs) in the PINK1-mediated mitophagy process are not fully understood. Here we discovered that miR-34a-5p suppresses PINK1 expression directly though two post-transcriptional non-classical binding modes, resulting in inhibition of PINK1-mediated mitophagy process. For in vivo experiments, brains were dissected from 8 weeks old and 40 weeks old C57BL/6 male mice to measure miR-34a-5p expression and PINK1 expression. For in vitro experiments, overexpression of miR-34a-5p mimics in HEK293 cells was performed to investigate the effect of miR-34a-5p on PINK1 expression and its regulatory mechanism, parkin recruitment and mitophagy process. The level of miR-34a-5p was upregulated and the level of PINK1 mRNA was downregulated in brains of aged mice. Both the 3′-untranslated region (3'UTR) and the Coding DNA sequence (CDS) of PINK1 mRNA were bound to the non-seed region of miR-34a-5p, rather than the seed region, resulting in a decrease in PINK1 expression. Endogenous miR-34a-5p knockout increased PINK1 expression. Further results indicated that miR-34a-5p inhibits mitophagy process by reduction of PINK1. miR-34a-5p hinders phosphorylated Ser65-ubiquitin (pS65-Ub) accumulation, prevents the mitochondrial recruitment of Parkin, attenuates ubiquitination and delays the clearance of damaged mitochondria. We firstly found that miR-34a-5p suppresses PINK1 directly and further regulates mitophagy through non-canonical modes. This finding hints at a crucial role of miR-34a-5p implicated in accelerating the pathogenesis of age-related neurological diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is the most common complication of type 2 diabetes mellitus, which could result in visual impairment. Accumulating studies have shown the implication of long non-coding RNAs (lncRNAs) in the pathogenesis of DR. Our aims are to investigate whether lncRNA SNHG7 plays a role during DR pathogenesis. Human retinal microvascular endothelial cells (HRMECs) were treated with high glucose (HG) to build cell model. Relative expression of RNAs were examined using qPCR, and western blot or immunofluorescence analysis was adopted to detect the protein expression. Cell viability, migration and angiogenic capacity of HRMECs were estimated through CCK-8, transwell and tube formation experiments, respectively. Dual-luciferase reporter and RNA pull down assays were employed to verify the interplay between miR-34a-5p and SNHG7 or XBP1. Mesenchymal stem cells (MSCs) were identified by examining typical surface makers using flow cytometry and the differentiation abilities via Alizarin red, Oil red O and Alcian blue staining. MSC-derived exosomes were verified by transmission electron microscopy and western blot. LncRNA SNHG7 sponged to and negatively regulated miR-34a-5p. SNHG7 overexpression repressed HG induced endothelial–mesenchymal transition (EndMT) and tube formation of HRMECs, while miR-34a-5p overexpression could reverse this effect. miR-34a-5p targeted and negative regulated XBP1. Knockdown of miR-34a-5p repressed HG induced EndMT and tube formation, which were partially blocked by XBP1 inhibition. MSC-derived exosomes could transfer SNHG7 to HRMECs and modulated EndMT and tube formation. The MSC-derived exosomal lncRNA SNHG7 suppresses EndMT and tube formation in HRMECs via miR-34a-5p/XBP1 axis. [ABSTRACT FROM AUTHOR]

While a number of therapeutic advances have been made in recent years, the overall survival of patients with head and neck squamous cell cancer (HNSCC) remains poor. MicroRNAs (miRNAs) are key drivers of oncogenic progression, with miR-34a-5p downregulation having been observed in many different tumor types. Here, we assessed the link between miR-34a-5p and HNSCC progression and the mechanistic basis for this relationship. Levels of miR-34a-5p in HNSCC tumors and cell lines were assessed via qPCR, after which we explored the functional importance of this miRNA in this oncogenic setting. Through luciferase reporter assays, the ability of miR-34a-5p to regulate flotillin-2 (FLOT-2) was further clarified. Overall, these analyses revealed that HNSCC tumors and cells exhibited marked miR-34a-5p downregulation that was linked to the progression of this tumor type. At a functional level, miR-34a-5p constrained the proliferation, migratory/invasive activity, and epithelial-mesenchymal transition induction in HNSCC cells. At the mechanistic level, miR-34a-5p was found to suppress FLOT-2 expression and to activate the MEK/ERK1/2 pathway. Overall, these results suggest that miR-34a-5p can function as a tumor suppressor miRNA in HNSCC owing to its ability to target FLOT-2, highlighting the promise of targeting this regulatory axis to treat HNSCC., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Background: Rheumatoid arthritis (RA) is a systemic and chronic inflammatory disease. The cellular glucose metabolism of fibroblast-like synoviocytes (FLSs) of RA has been revealed to be essential to the pathogenesis and development of RA. To date, the precise roles and molecular mechanisms of long noncoding RNA TUG1 in RA have not been elucidated., Methods: TUG1 and miR-34a-5p were detected by qRT-PCR. Interactions between lncRNA-miRNA and miRNA-mRNA were validated by RNA pull-down assay and luciferase assay. The glucose metabolism was evaluated by glucose uptake and extracellular acidification rate (ECAR). Cell viability was determined by MTT assay and Annexin V assay., Results: TUG1 expression was significantly upregulated in synovial fibroblast-like synoviocytes (FLSs) compared with normal FLSs. Functional assays uncovered that silence of TUG1 suppressed FLSs-RA invasion, migration, glucose metabolism, and increased apoptosis. Bioinformatics analysis indicated that TUG1 interacted with miR-34a-5p. RNA pull-down assay and luciferase assay validated that TUG1 sponged miR-34a-5p in FLSs-RA. Overexpression of miR-34a-5p effectively inhibited glucose metabolism of FLSs-RA. Furthermore, the glucose metabolism of FLSs-RA was significantly elevated compared with normal FLSs. The glucose metabolism enzyme, LDHA, was directly targeted by miR-34a-5p in FLSs. Rescue experiments validated that the miR-34a-5p-inhibited glucose metabolism of FLSs-RA was through targeting LDHA. Finally, we showed restoration of miR-34a-5p in TUG1-overexpressing FLSs-RA successfully overcame the TUG1-promoted glucose metabolism and apoptosis resistance via targeting LDHA., Conclusion: The present study uncovered critical roles and molecular mechanisms underlying the TUG1-mediated glucose metabolism and apoptosis of FLSs-RA through modulating the miR-34a-5p-LDHA pathway in fibroblast-like synoviocytes of rheumatoid arthritis., (© 2021 The Authors. Journal of Clinical Laboratory Analysis published by Wiley Periodicals LLC.)

Background: Hirschsprung's disease (HSCR) is a common defect in newborns, and studies have revealed that long non-coding RNA (lncRNA) is involved in the progression of HSCR. This research study aims to investigate the mechanism of downregulated RNA in cancer (DRAIC) on cell proliferation and migration in HSCR., Methods: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the expression of DRAIC in HSCR bowel stenosis tissues and normal colon tissues. Cell-counting kit-8 (CCK-8) and Transwell assays were employed to explore whether cellular functions change after overexpression or knockdown of the DRAIC in SH-SY5Y cells and human 293T cells. Protein expression levels were determined by Western blot analysis. RNA pull-down and dual-luciferase reporter assays were used to confirm the competitive relationship of DRAIC and integrin subunit alpha 6 (ITGA6) through their association with miR-34a-5p., Results: The lncRNA DRAIC was significantly increased in colon tissue from HSCR patients. The overexpression of DRAIC inhibited SH-SY5Y cell and human 293T cell proliferation and migration. Knockdown of DRAIC, however, promoted cell proliferation and migration. The RNA pull-down and dual-luciferase reporter assays have proven the competitive relationship between DRAIC and ITGA6 through their association with miR-34a-5p. Further rescue experiments have confirmed that DRAIC regulates cell proliferation and migration by affecting the miR-34a-5p/ITGA6 signal axis in HSCR., Conclusion: DRAIC promoted cell proliferation and migration by regulating the miR-34a-5p/ITGA6 signal axis in HSCR., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s). Published by Upsala Medical Society.)

C1q/tumor necrosis factor-related protein-6 (CTRP6) is a newly identified adipokine involved in diverse biological processes. However, its role in salivary glands remains unknown. Here, we demonstrated that CTRP6 was mainly distributed in the nuclei, apicolateral membranes, and cytoplasm of human submandibular glands (SMGs), serous cells of parotid glands, and ducts and apicolateral membranes of serous cells in rats and mice. CTRP6 inhibited the apoptosis rate and reversed the increased levels of cleaved caspase 3, caspase 8, caspase 9, and cytochrome C and the decreased Bcl-2 expression induced by tumor necrosis factor (TNF)-α in both SMG-C6 cells and cultured human SMG tissues. Microarray analysis identified 43 differentially expressed microRNAs (miRNAs) in the SMGs of nonobese diabetic mice. miR-34a-5p was selected due to its upregulation by TNF-α, which was abolished by CTRP6. The miR-34a-5p inhibitor promoted whereas the miR-34a-5p mimic suppressed the effects of CTRP6 on TNF-α-induced apoptosis. CTRP6 increased AMP-activated protein kinase (AMPK) phosphorylation and reversed TNF-α-induced SIRT1 downregulation in salivary cells. AraA, an AMPK inhibitor, reversed the effects of CTRP6 on TNF-α-induced alterations in the levels of SIRT1, miR-34a-5p, Bcl-2, and cleaved caspase 3 in vitro and ex vivo, whereas activating AMPK by AICAR reversed the decrease in SIRT1 expression and increase in miR-34a-5p expression induced by TNF-α. Inhibition of SIRT1 by EX527 suppressed the effects of CTRP6 on TNF-α-induced changes in miR-34a-5p and apoptosis-related proteins. Our findings indicate that salivary glands are novel sites for CTRP6 synthesis and secretion. CTRP6 protects acinar cells against TNF-α-induced apoptosis via AMPK/SIRT1-modulated miR-34a-5p expression., (© 2021 Wiley Periodicals LLC.)