miR-26a Expression Research Articles

Apigenin Attenuates Hippocampal Microglial Activation and Restores Cognitive Function in Methotrexate-Treated Rats: Targeting the miR-15a/ROCK-1/ERK1/2 Pathway

Microglial activation underpins the methotrexate (MTX)-induced neurotoxicity; however, the precise mechanism remains unclear. This study appraised the potential impact of apigenin (Api), a neuroprotective flavonoid, in MTX-induced neurotoxicity in rats in terms of microglial activation through targeting the miR-15a/Rho-associated protein kinase-1 (ROCK-1)/extracellular signal-regulated kinase 1/2 (ERK1/2) pathway. Male Sprague Dawley rats were randomly divided into 4 groups: Normal control (saline i.p. daily and i.v. on days 8 and 15); Api control (20 mg/kg, p.o.) daily for 30 days; MTX-alone (75 mg/kg, i.v.) on days 8 and 15, then four i.p. injections of leucovorin (LCV): 6 mg/kg after 18 h, then three doses (3 mg/kg) every 8 h post-MTX; and Api co-treated (20 mg/kg/day, p.o.) throughout the model for 30 days, with administration of MTX and LCV as in group 3. MTX administration elevated hippocampal ionized calcium-binding adaptor protein-1 (Iba-1) immunostaining, indicating microglial activation. This was accompanied by neuroinflammation, oxidative stress, and enhanced apoptosis manifested by elevated hippocampal interleukin-1β, malondialdehyde, and caspase-3, and decreased reduced glutathione levels. Concurrently, abated miR-15a expression, overexpression of its target ROCK-1, diminished downstream ERK1/2 and cAMP response element-binding protein (CREB) phosphorylation, and decreased hippocampal brain-derived neurotrophic factor (BDNF) levels were observed. Api mitigated the MTX-induced neurotoxicity by reversing the biochemical, histopathological, and behavioral derangements tested by novel object recognition and Morris water maze tests. Conclusively, Api lessens MTX-induced neuroinflammation, oxidative stress, and apoptosis and boosts cognitive function through inhibiting microglial activation via modulating the miR-15a/ROCK-1/ERK1/2/CREB/BDNF pathway.Graphical Graphical abstract showing the effects of methotrexate and apigenin co-treatment in MTX-induced neurotoxicity model.On the left, methotrexate (MTX) administration to rats resulted in hippocampal miR-15a downregulation, which triggered an enhanced expression of its target ROCK-1, consequently inhibiting the downstream ERK1/2/CREB/BDNF pathway, instigating a state of microglial activation, neuroinflammation, oxidative stress, and apoptosis. On the other hand, apigenin (Api) co-treatment restored miR-15a, inhibited ROCK-1 expression, and activated the ERK1/2/CREB/BDNF pathway, leading to diminished hippocampal microglial activation, neuroinflammation, and apoptosis, and restoration of the redox balance, along with improvement in memory and cognitive function of the MTX-treated rats.

Helicobacter pylori infection induces abnormal expression of pro-angiogenic gene ANGPT2 and miR-203a in AGS gastric cell line.

Helicobacter pylori colonizes the stomach and induces an inflammatory response that can develop into gastric pathologies including cancer. The infection can alter the gastric vasculature by the deregulation of angiogenic factors and microRNAs. In this study, we investigate the expression level of pro-angiogenic genes (ANGPT2, ANGPT1, receptor TEK), and microRNAs (miR-135a, miR-200a, miR-203a) predicted to regulate those genes, using H. pylori co-cultures with gastric cancer cell lines. In vitro infections of different gastric cancer cell lines with H. pylori strains were performed, and the expression of ANGPT1, ANGPT2, and TEK genes, and miR-135a, miR-200a, and miR-203a, was quantified after 24h of infection (h.p.i.). We performed a time course experiment of H. pylori 26695 infections in AGS cells at 6 different time points (3, 6, 12, 28, 24, and 36h.p.i.). The angiogenic response induced by supernatants of non-infected and infected cells at 24h.p.i. was evaluated in vivo, using the chicken chorioallantoic membrane (CAM) assay. In response to infection, ANGPT2 mRNA was upregulated at 24h.p.i, and miR-203a was downregulated in AGS cells co-cultured with different H. pylori strains. The time course of H. pylori 26695 infection in AGS cells showed a gradual decrease of miR-203a expression concomitant with an increase of ANGPT2 mRNA and protein expression. Expression of ANGPT1 and TEK mRNA or protein could not be detected in any of the infected or non-infected cells. CAM assays showed that the supernatants of AGS-infected cells with 26695 strain induced a significantly higher angiogenic and inflammatory response. Our results suggest that H. pylori could contribute to the process of carcinogenesis by downregulating miR-203a, which further promotes angiogenesis in gastric mucosa by increasing ANGPT2 expression. Further investigation is needed to elucidate the underlying molecular mechanisms.

Epigenetic and genetic inactivation of tumor suppressor miR-135a in non-small-cell lung cancer.

Despite therapeutic advances, lung cancer prognosis remains poor. Loss of heterozygosity (LOH) in the 3p21 region is well documented in lung cancer, but the specific causative genes have not been identified. Here, we aimed to examine the clinical impact of miR-135a, located in the 3p21 region, in lung cancer. miR-135a expression was assessed using quantitative real-time polymerase chain reaction. LOH was analyzed at microsatellite loci D3S1076 and D3S1478, and promoter methylation status was determined by pyrosequencing of resected samples of primary non-small-cell lung cancer (NSCLC). The regulation of telomerase reverse transcriptase (TERT) was evaluated in lung cancer cells H1299 by luciferase report assays after treatment with miR-135a mimics. miR-135a was significantly downregulated in squamous cell cancer (SCC) tumor tissues compared to normal tissues (p=0.001). Low miR-135a expression was more frequent in patients with SCC (p=2.9 × 10-4 ) and smokers (p=0.01). LOH and hypermethylation were detected in 27.8% (37/133) and 17.3% (23/133) of the tumors, respectively. Overall, 36.8% (49/133) of the NSCLC cases harbored either miR-135a LOH or promoter hypermethylation. The frequencies of LOH and hypermethylation were significantly associated with SCCs (p=2× 10-4 ) and late-stage (p=0.04), respectively. MiR-135a inhibited the relative luciferase activity of psiCHECK2-TERT-3'UTR. These results suggest that miR-135a may act as a tumor suppressor to play an important role in lung cancer carcinogenesis, which will provide a new insight into the translational value of miR-135a. Further large-scale studies are required to confirm these findings.

Astragaloside IV inhibits angiotensin II-induced aortic dissection formation by regulating miR-320a/matrix metallopeptidase 9 axis

This study explored the role of miR-320a and Matrix metallopeptidase 9 (MMP-9) in aortic dissection (AD) formation. Aortic tissue diameter (LD) and medial thickness (MT) were measured after the AD model was established. Aortic smooth muscle cells (VSMCs) were assigned into blank group, Astragaloside IV (AS-IV), which was treated with 100, 150 or 200 μg/mL and AngII group. Cells in the AngII group were added with MMP9 inhibitor (MMP9 inhibitor group) and mimics (MMP9 mimics group), followed by analysis of cell proliferation, apoptosis, and target gene for miR-320a. Aortic tissue diameter(LD) from the AD group was significantly higher and MT was lower than in the control group (p<0.05). VSMCs proliferative activity in the AS-IV group and AngII group was increased significantly (p <0.05), with lower activity in the AS-IV group than AngII group (p < 0.05). After transfection, the VSMCs apoptosis in the AngII group was decreased (p <0.05). In addition, cell migration in the AS-IV and AngII groups increased (p <0.05), with lower ability in the AS-IV group than in the AngII group (p <0.05). Alpha smooth muscle Actin (α-SMA) expression was elevated after AngII stimulation and decreased after AS-IV treatment (p <0.05). After AngII stimulation, miR-320a and MMP9 were upregulated (p <0.05) and downregulated by AS-IV (p <0.05). MMP9 is a target gene for miR-320a. miR-320a and MMP9 expressions in the AS-IV group were significantly decreased, with lowest levels in the AS-IV-200 μg/mL group. In addition, MMP9 overexpression reduced the AngII expression. The expression of miR-320a/MMP9 axis was low in the AD, and activity were increased after AngII stimulation. In conclusion, As-IV can relieve the occurrence of AD via regulation of miR-320a/MMP9 axis.

LncRNA TPT1-AS1 promotes cell migration and invasion in esophageal squamous-cell carcinomas by regulating the miR-26a/HMGA1 axis.

lncRNA TPT1-AS1 plays an oncogenic role in ovarian and cervical cancers. However, its involvement in the pathological progress of esophageal squamous-cell carcinomas (ESCCs) is unclear. lncRNA TPT1-AS1 was mainly localized in the cytoplasm of ESCC cells and interacted with miR-26a. In ESCC tissues, lncRNA TPT1-AS1 level was obviously increased, while miR-26a level was decreased. Interestingly, lncRNA TPT1-AS1 level was not significantly correlated with miR-26a level but was positively correlated with HMGA1 mRNA, a target of miR-26a. In ESCC cell lines KYSE510 and KYSE-30, lncRNA TPT1-AS1 overexpression enhanced HMGA1 expression, while it had no effect on miR-26a expression. Cell migration and proliferation assays indicated that lncRNA TPT1-AS1 and HMGA1 overexpression promoted ESCC cell migration and invasion, while their effects were alleviated by miR-26a overexpression. The migration and invasion of ESCC cells were suppressed by lncRNA TPT1-AS1 knockdown. In conclusion, lncRNA TPT1-AS1 plays an oncogenic role in ESCC and might function by upregulating HMGA1 via sponging miR-26a.

MEIS1 Is a Common Transcription Repressor of the miR-23a and NORHA Axis in Granulosa Cells.

MicroRNA-23a (miR-23a) is an endogenous small activating RNA (saRNA) involved in ovarian granulosa cell (GC) apoptosis and sow fertility by activating lncRNA NORHA transcription. Here, we reported that both miR-23a and NORHA were repressed by a common transcription factor MEIS1, which forms a small network regulating sow GC apoptosis. We characterized the pig miR-23a core promoter, and the putative binding sites of 26 common transcription factors were detected in the core promoters of both miR-23a and NORHA. Of them, transcription factor MEIS1 expression was the highest in the ovary, and widely distributed in various ovarian cells, including GCs. Functionally, MEIS1 is involved in follicular atresia by inhibiting GC apoptosis. Luciferase reporter and ChIP assays showed that transcription factor MEIS1 represses the transcription activity of miR-23a and NORHA through direct binding to their core promoters. Furthermore, MEIS1 represses miR-23a and NORHA expression in GCs. Additionally, MEIS1 inhibits the expression of FoxO1, a downstream of the miR-23a/NORHA axis, and GC apoptosis by repressing the miR-23a/NORHA axis. Overall, our findings point to MEIS1 as a common transcription repressor of miR-23a and NORHA, and develop the miR-23a/NORHA axis into a small regulatory network regulating GC apoptosis and female fertility.

Overexpression of Mirna 26A and 26B with Mmp-9 are Valuable Diagnostic Biomarkers for Colorectal Cancer Patients

Background: The key role of miRNA expression in incidence and progression of colorectal cancer (CLC) have been developed over the last decade. Materials & methods: A total of153 subjects were enrolled into two phases: 14 selected miRNAs were first evaluated in 50 subjects, then miR-26a and miR-26b relative expression were further evaluated in 103 subjects and their target protein MMP-9 was measured. Results: miR-26a and-26b showed highly significant overexpression. Both miR-26a and -26b (p<0.001) had high diagnostic efficacy for CRC. There was a significant increase in serum MMP-9 protein in CRC patients with positive correlation with miR-26a and -26b expression levels (p<0.001). Conclusion: miRNA 26a and 26b with MMP-9 can be used as diagnostic biomarker for CRC patients.

Quercetin up-regulates the expression of tumor-suppressive microRNAs in human cervical cancer.

Quercetin, a flavonol present in many vegetables and fruits, has been identified as a chemoprevention agent in several cancer models. However, the molecular mechanism of quercetin's anticancer activity is not entirely understood. MicroRNAs (miRNAs), small noncoding RNAs, have been reported to play key roles in various biological processes by regulating their target genes. We hypothesized that quercetin can exert an anticancer effect through the regulation of miRNAs. To test this hypothesis, we investigated the effects of quercetin on the expression of tumor-suppressive miRNAs in cervical cancer. Quercetin up-regulated the in vivo and in vitro expression of tumor-suppressive miRNAs miR-26b, miR-126, and miR-320a. Quercetin suppressed the level of β-catenin, encoded by catenin beta 1 (CTNNB1), by up-regulating miR-320a in HeLa cells. Moreover, quercetin increased the expression of mir-26b, mir-126, and mir-320a precursors in HeLa cells. The results from this study show that quercetin has the potential to prevent cervical cancer by regulating the expression of tumor-suppressive miRNAs.

Sevoflurane attenuates myocardial ischemia/reperfusion injury by up-regulating microRNA-99a and down-regulating BRD4.

It has been explored that sevoflurane (Sevo) is cardioprotective in myocardial ischemia/reperfusion injury (MI/RI) and mediates microRNA (miRNA) expression that control various physiological systems. Enlightened by that, the work was programmed to decode the mechanism of Sevo and miR-99a with the participation of bromodomain-containing protein 4 (BRD4). MI/RImodel was established on mice. MI/RI modeled mice were exposed to Sevo or injected with miR-99a or BRD4-related vectors to identify their functions in cardiac function, pathological injury, cardiomyocyte apoptosis, inflammation, and oxidative stress in MI/RI mice. MiR-99a and BRD4 expression in myocardial tissues were tested, and their relation was further validated. MiR-99a was down-regulated, and BRD4 was up-regulated in MI/RI mice. Sevo up-regulated miR-99a to inhibit BRD4 expression in myocardial tissues of MI/RI mice. Sevo improved cardiac function, relieved myocardial injury, repressed cardiomyocyte apoptosis, and alleviated inflammation and oxidative stress in mice with MI/RI. MiR-99a restoration further enhanced the positive effects of Sevo on mice with MI/RI. Overexpression of BRD4 reversed up-regulation of miR-99a-induced attenuation of MI/RI in mice. The work delineated that Sevo up-regulates miR-99a to attenuate MI/RI by inhibiting BRD4.

Transcriptomic profiling of miR-203a inhibitor and miR-34b-injected zebrafish (Danio rerio) validates oil-induced neurological, cardiovascular and eye toxicity response pathways

The global sequencing of microRNA (miRNA; miR) and integration to downstream mRNA expression profiles in early life stages (ELS) of fish following exposure to crude oil determined consistently dysregulated miRNAs regardless of the oil source or fish species. The overlay of differentially expressed miRNAs and mRNAs into in silico software determined that the key roles of these miRNAs were predicted to be involved in cardiovascular, neurological and visually-mediated pathways. Of these, altered expression of miRNAs, miR-203a and miR-34b were predicted to be primary targets of crude oil. To better characterize the effect of these miRNAs to downstream transcript changes, zebrafish embryos were microinjected at 1 h post fertilization (hpf) with either a miR-203a inhibitor or miR-34b. Since both miRs have been shown to be associated with aryl hydrocarbon receptor (AhR) function, benzo(a)pyrene (BaP), a potent AhR agonist, was used as a potential positive control. Transcriptomic profiling was conducted on injected and exposed larvae at 7 and 72 hpf, and eye morphology assessed following exposure at 72 hpf. The top predicted physiological system disease and functions between differentially expressed genes (DEGs) shared with miR-203a inhibitor-injected and miR-34b-injected embryos were involved in brain formation, and the development of the central nervous system and neurons. When DEGs of miR-203a inhibitor-injected embryos were compared with BaP-exposed DEGs, alterations in nervous system development and function, and abnormal morphology of the neurosensory retina, eye and nervous tissue were predicted, consistent with both AhR and non-AhR pathways. When assessed morphologically, the eye area of miR-203a inhibitor and miR-34b-injected and BaP-exposed embryos were significantly reduced. These results suggest that miR-203a inhibition and miR-34b overexpression contribute to neurological, cardiovascular and eye toxicity responses that are caused by oil and PAH exposure in ELS fish, and are likely mediated through both AhR and non-AhR pathways.

Preparationandinhibitoryeffectofsalicin dimethyl etherinLaryngealcancercellsthrough theapoptosisactivation.

Laryngeal cancer is detected commonly worldwide, and it ranks second highest in incidence among the respiratory tract neoplasms following only head and neck squamous cell cancer. In the present study salicin dimethyl ether was synthesized and evaluated against laryngeal cancers cells for anticancer property. MTT assay was used for the measurement of changes in TU686 and Tu212 cell proliferation while as induced apoptosis was detected by flow cytometry. Protein expression was determined by western blotting and expression of mRNA by RT-PCR assay. In the present study salicin dimethyl ether was synthesized by the reaction of salicin with methyl iodide using sodium hydride as base. Salicin dimethyl ether treatment led to a significant decrease in TU686 and Tu212 cell proliferation in a dose-dependent manner. In TU686 and Tu212 cells salicin dimethyl ether treatment caused a significant increase in cell apoptosis and elevated caspase-3 activity. Treatment with salicin dimethyl ether led to a prominent reduction in Bcl-2 protein expression in TU686 and Tu212 cells at 72 h. Salicin dimethyl ether treatment led to a prominent decrease in p-PI3K and p-Akt protein expression in TU686 and Tu212 cells, compared to the untreated cells. A significant increase in miR‑15a expression in TU686 and Tu212 cells was observed on treatment with salicin dimethyl ether at 72 h. In summary, the current study demonstrates that salicin dimethyl ether, a synthetic derivative of salicin, suppresses proliferation of TU686 and Tu212 cells. The underlying mechanism involves induction of apoptosis, inhibition of PI3K/Akt pathway and promotion of miR-15a expression. Therefore, salicin dimethyl ether may be used for inhibition of laryngeal cancer growth, however, in vivo studies need to be conducted to confirm the effect.

MiR-99a alleviates apoptosis and extracellular matrix degradation in experimentally induced spine osteoarthritis by targeting FZD8

BackgroundOur previous study identified miR-99a as a negative regulator of early chondrogenic differentiation. However, the functional role of miR-99a in the pathogenesis of osteoarthritis (OA) remains unclear.MethodsWe examined the levels of miR-99a and Frizzled 8 (FZD8) expression in tissue specimens. Human SW1353 chondrosarcoma cells were stimulated with IL-6 and TNF-α to construct an in vitro OA environment. A luciferase reporter assay was performed to analyze the relationship between miR-99a and FZD8. CCK-8 assays, flow cytometry, and ELISA assays were used to assess cell viability, apoptosis, and inflammatory molecule expression, respectively. Percutaneous intra-spinal injections of papain mixed solution were performed to create an OA Sprague–Dawley rat model. Alcian Blue staining, Safranin O Fast Green staining, and Toluidine Blue O staining were performed to detect the degrees of cartilage injury.ResultsMiR-99a expression was downregulated in the severe spine OA patients when compared with the mild spine OA patients, and was also decreased in the experimentally induced in vitro OA environment when compared with the control environment. Functionally, overexpression of miR-99a significantly suppressed cell apoptosis and extracellular matrix degradation stimulated by IL-6 and TNF-α. FZD8 was identified as a target gene of miR-99a. Furthermore, the suppressive effects of miR-99a on cell injury induced by IL-6 and TNF-α were reversed by FZD8 overexpression. Moreover, the levels of miR-99a expression were also reduced in the induced OA model rats, and miR-99a agomir injection relieved the cartilage damage. At the molecular level, miR-99a overexpression downregulated the levels of MMP13, β-catenin, Bax, and caspase-3 protein expression and upregulated the levels of COL2A1 and Bcl-2 protein expression in the in vitro OA-like chondrocyte model and also in the experimental OA model rats.ConclusionsOur data showed that miR-99a alleviated apoptosis and extracellular matrix degradation by targeting FZD8, and thereby suppressed the development and progression of experimentally induced spine osteoarthritis.

MiRNA-26a reduces vascular smooth muscle cell calcification by regulating connective tissue growth factor

To investigate the regulatory role of miRNA-26a in vascular smooth muscle cell (VSMC) calcification by regulating connective tissue growth factor (CTGF). Rat thoracic aorta VSMCs (A7r5 cells) with induced calcification were treated with AR234960 agonist or transfected with miR-26a mimic, or with both treatments. Alizarin red staining was used to determine calcium deposition, and phosphatase (ALP) activity in the cells was measured. The mRNA and protein expressions of miR-26a, OPG, OPN, BMP-2 and collagen Ⅱ were detected using qPCR and Western blotting. The binding of miR-26a to CTGF was verified using dual luciferase reporter gene assay. After induced calcification, A7r5 cells showed gradually decreased miR-26a expression (P < 0.05) and progressively increased CTGF expression (P < 0.05) with the extension of induction time. Treatment of the cells with AR234960 obviously increased calcification in the cells, while transfection with miR-26a mimic significantly reduced cell calcification. The calcifying cells showed significantly increased ALP activity and expressions of OPN, BMP-2 and collagen Ⅱ (P < 0.05) and lowered OPG expression (P < 0.05), and treatment with AR234960 did not produce obvious effects on these changes (P > 0.05). Transfection with miR-26a mimic resulted in significantly decreased ALP activity and expressions OPN, BMP-2 and collagen Ⅱ expression (P < 0.05) and increased OPG expression (P < 0.05) in the calcifying cells. These effects of miR-26a mimic was significantly attenuated by treatment of the cells with AR234960 (P < 0.05). The result of luciferase reporter gene assay confirmed the binding of miR-26a to CTGF. miRNA-26a can effectively alleviate vascular calcification by lowering the level of CTGF, reducing ALP activity and the expressions of OPN, BMP-2 and collagen Ⅱ, and increasing the expression of OPG.

Persistent Organic Pollutants and Dysregulation of microRNAs Expression in Humans and Animals - A Systematic Literature Review

Background: MicroRNAs (miRNAs) are key regulators in many physiological processes. Evidence suggests that exposure to persistent organic pollutants (POPs) is associated with miRNA dysregulation. Exposure to POPs is ubiquitous and these chemicals are characterized by their environmental persistence. It is therefore of public health concern to understand the relationship between POPs and miRNA as it relates to health outcomes. Objectives: The objective of this systematic review is to evaluate the relationship between exposure to POPs including per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), dichloro-diphenyl-trichloroethane (DDT), hexachlorobenzene (HCB), and polybrominated diphenyl ethers (PBDEs), with miRNA expression in both human and animal studies. Methods: The systematic search of the literature was conducted in PubMed and Embase. Search results of human and animal studies were included if they included at least one POP of interest in relation to at least one miRNA. Data were synthesized to determine the direction and statistical significance of associations between POPs and miRNA. Finally, a review of disease pathways was conducted for miRNAs that were consistently associated with POPs. Results: Our search identified 35 studies, 8 of humans and 27 of model organisms. PFAS were associated with decreased expression of miR-144, miR-19 and miR-193, and increased expression of miR-26b, miR-199a-3p, miR-122 and miR-128 across studies. PCBs were associated with increased expression of miR-15a, miR-21, miR-1537 and decreased let-7b in both humans and animals. Pathway review suggested that PFAS-associated miRNAs are all involved in prostate cancer, hepatocellular carcinoma and nonalcoholic fatty liver disease, while PCB-associated miRNA are associated with gastric cancer. Conclusion: This is the first systematic review of the association of POPs with miRNAs in humans and model organisms. Large-scale prospective human studies are now warranted to examine the role of miRNAs as mediators between POPs and health outcomes. Keywords: persistent organic pollutants, miRNAs, systematic review

Carboxyl Group-Modified Myoglobin Induces TNF-α-Mediated Apoptosis in Leukemia Cells.

Previous studies have shown that chemical modification may increase the activity of proteins or confer novel activity to proteins. Some studies have indicated that myoglobin (Mb) is cytotoxic; however, the underlying mechanisms remain unclear. In this study, we investigated whether chemical modification of the carboxyl group by semicarbazide could promote the Mb cytotoxicity in human leukemia U937 cells and the underlying mechanism of semicarbazide-modified myoglobin (SEM-Mb)-induced U937 cell death. The semicarbazide-modified Mb (SEM-Mb) induced U937 cell apoptosis via the production of cleaved caspase-8 and t-Bid, while silencing of FADD abolished this effect. These findings suggest that SEM-Mb can induce U937 cell death by activating the death receptor-mediated pathway. The SEM-Mb inhibited miR-99a expression, leading to increased NOX4 mRNA and protein expression, which promoted SIRT3 degradation, and, in turn, induced ROS-mediated p38 MAPK phosphorylation. Activated p38 MAPK stimulated miR-29a-dependent tristetraprolin (TTP) mRNA decay. Downregulation of TTP slowed TNF-α mRNA turnover, thereby increasing TNF-α protein expression. The SEM-Mb-induced decrease in cell viability and TNF-α upregulation were alleviated by abrogating the NOX4/SIRT3/ROS/p38 MAPK axis or ectopic expression of TTP. Taken together, our results demonstrated that the NOX4/SIRT3/p38 MAPK/TTP axis induces TNF-α-mediated apoptosis in U937 cells following SEM-Mb treatment. A pathway regulating p38 MAPK-mediated TNF-α expression also explains the cytotoxicity of SEM-Mb in the human leukemia cell lines HL-60, THP-1, K562, Jurkat, and ABT-199-resistant U937. Furthermore, these findings suggest that the carboxyl group-modified Mb is a potential structural template for the generation of tumoricidal proteins.

MiR-135a is highly expressed and aggravates inflammatory response in sepsis by targeting MYOM1.

Our research attempted to explore the effect of miR-135a on lipopolysaccharide (LPS)-induced THP-1cells damage and its potential mechanism. LPS (1 μg/mL) was selected to mimic the injury of sepsis in vitro. qRT-PCR was used to detect miR-135a expression. The association between miR-135a and Myomesin 1 (MYOM1) was speculated bythe predication website and confirmed by the dual-luciferase assay. MYOM1 expression was observed by qRT-PCR and western blotting assays. The biological properties of THP-1cells were analyzed by cell counting kit-8 and flow cytometry assays. The concentration of TNF-α, IL-6 and IL-8 in cell supernatant was calculated by enzyme-linkedimmunosorbentassay. A marked augmentation of miR-135a was observed in LPS-induced THP-1 cells. Moreover, depletion of miR-135a alleviated the LPS-induced THP-1 cells injury from the perspective of improving cell viability and reducing cell apoptosis. Importantly, MYOM1, which was under expressed in LPS-induced THP-1 cells, was identified as a target of miR-135a and negatively regulated by miR-135a. Additionally, the mitigative impact of miR-135a inhibitor on THP-1cells damage triggered by LPS was suppressed by MYOM1 depletion. Our study suggested that the protective effect of miR-135a inhibitor on LPS-induced THP-1 cells injury was realized by regulation of MYOM1, which might afford a pair of novel molecules for sepsis clinical diagnosis.

Circulating salivary and serum miRNA-182, 320a, 375 and 503 expression levels in type 2 diabetes.

Early-stage diagnosis of diabetes through non-invasive and diagnostic biofluid-like saliva has become a very popular approach to facilitate future preventive interventions and improve patient care. Meanwhile, the alteration of small non-coding RNA in human fluids has been suggested as a probable precedent for the early stages of diabetes. In the present study, we checked the expression of miR-320a, 182-5p, 503, and 375 by using quantitative PCR in both stimulated and unstimulated saliva and blood samples of 40 adult patients with type-2 diabetes compared to 40 healthy individuals. In addition, we have sought to understand the possibility that miRNAs could provide new information about the status of type 2 diabetes in salivary samples beyond what can now be identified from blood samples and link their expression to the presence of clinically relevant risk factors. For this purpose, we have used a set of multivariate models. The results showed that three miRNAs were more highly expressed in patients with type 2 diabetes, while miR-320-a was down-regulated in those patients compared to healthy subjects. Furthermore, the data showed that miR-320a was the most reliable predictor for distinguishing diabetic patients from healthy subjects, with AUCs of 0.997, 0.97, and 0.99 (97.4% sensitivity and 100% specificity, p = 0.001) for serum, unstimulated, and stimulated saliva samples, respectively. Interestingly, the results of this study indicated that the amount of four miRNAs expressed in stimulated saliva was the same as in serum samples, which could conclude that specific miR-320a and 503 in stimulated saliva may introduce credible, non-invasive, and diagnostic biomarkers that can be used to monitor diabetic patients' status, while there is a need to design more research studies to confirm these findings.

MiR-15a and miR-20b sensitize hepatocellular carcinoma cells to sorafenib through repressing CDC37L1 and consequent PPIA downregulation

Sorafenib is a classical targeted drug for the treatment of advanced hepatocellular carcinoma (HCC), but intrinsic resistance severely limited its therapeutic effects. In the present study, we aimed to identify crucial genes in HCC cells that affect sorafenib resistance by a CRISPR/Cas9 genome-scale screening. The results indicated that the deficiency of miR-15a and miR-20b contributed to sorafenib resistance, whereas exogenous expression of miR-15a and miR-20b enhanced sorafenib sensitivity of HCC cells by cell viability, colony formation, and flow cytometry analyses. Further analyses revealed that cell division cycle 37 like 1 (CDC37L1) as a common target of miR-15a and 20b, was negatively regulated by the two miRNAs and could enhance sorafenib resistance of HCC cells in vitro and in vivo. Mechanistically, CDC37L1, as a cochaperone, effectively increased the expression of peptidylprolyl isomerase A (PPIA) through strengthening the binding between heat shock protein 90 (HSP90) and PPIA. The results from immunohistochemical staining of a HCC tissue microarray revealed a positive association between CDC37L1 and PPIA expression, and high expression of CDC37L1 and PPIA predicted worse prognosis of HCC patients after sorafenib therapy. Taken together, our findings reveal crucial roles of miR-15a, miR-20b, CDC37L1, and PPIA in sorafenib response of HCC cells. These factors may serve as therapeutic targets and predict prognosis for HCC treated with sorafenib.

The minor allele of rs17427875 in long non-coding RNA-HOXA11-AS influences the prognosis of subarachnoid hemorrhage (SAH) via modulating miR-15a and STAT3 expression

Background: HOAX11-AS was reported to promote the progression of liver cancer via the signaling pathway of miR-15a-3p/STAT3. In this study, we investigated the effect of rs17427875 on the prognosis of subarachnoid hemorrhage (SAH) and its underlying molecular mechanisms.Methods: 158 SAH patients were recruited and grouped according to their genotypes rs17427875. Peripheral blood and cerebrospinal fluid (CSF) samples were collected for subsequent analysis. Quantitative real-time PCR, luciferase assays, Western blot and ELISA were performed to analyze the correlations between the expression of lncRNA-HOXA11-AS, miR-15a, TNF-α and NF-κB.Results: The survival rate was remarkably higher in SAH patients carrying the AA genotype of rs17427875 when compared with those carrying the AT genotype. The expression of miR-15a was significantly repressed in the peripheral blood and CSF of SAH patients carrying the AT allele when compared with that in patients carrying the AA allele. MiR-15a showed a remarkable efficacy in inhibiting the luciferase activity of wild type lncRNA-HOXA11-AS and STAT3 in THP-1 cells. P-HOXA11-AS-T showed a stronger ability to suppress the expression of miR-15a and activate the expression of STAT3, TNF-α and NF-κB in THP-1 cells when compared with P-HOXA11-AS-A.Conclusions: The findings demonstrated that the presence of the minor allele of rs17427875 in lncRNA-HOXA11-AS could increase the expression level of lncRNA-HOXA11-AS, thus elevating the expression level of STAT3 via down-regulating miR-15a, and increased STAT3 expression could aggravate inflammation to cause poor prognosis of SAH. Therefore, the rs17427875 polymorphism can be used as a potential biomarker for the prognosis of SAH.

Long non-coding RNA growth arrest specific 5 regulates the T helper 17/regulatory T balance by targeting miR-23a in myasthenia gravis.

ObjectiveMyasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder. Recent studies report that long non-coding RNAs (lncRNAs) play vital roles in the pathogenesis of various diseases. This study explored the molecular mechanism of lncRNA growth arrest specific 5 (GAS5) in regulating the T helper 17 (Th17)/regulatory T (Treg) cell balance in MG.MethodsGAS5 and miR-23a expression levels were detected by quantitative reverse transcription polymerase chain reaction. Flow cytometry was performed to examine the proportion of Th17 and Treg cells in CD4+ T cells from MG patients. The interaction between GAS5 and miR-23a was verified by luciferase reporter and RNA immunoprecipitation assays. Levels of Th17 and Treg-related proteins were examined using western blots and enzyme-linked immunosorbent assays.ResultsGAS5 expression levels were significantly decreased in the CD4+ T cells of MG patients, and GAS5 overexpression restrained Th17 differentiation in CD4+ T cells. Moreover, miR-23a was confirmed as a downstream target of GAS5 and negatively regulated by GAS5 through a direct interaction. Further exploration showed that GAS5 can inhibit Th17 differentiation by downregulating miR-23a.ConclusionCollectively, our results indicate that GAS5 can regulate the Th17/Treg balance by targeting miR-23a expression, providing a scientific basis for clinical therapeutic development for MG.