MicroRNA-351-5p aggravates intestinal ischaemia/reperfusion injury through the targeting of MAPK13 and Sirtuin-6

Estradiol and vitamin D exert a synergistic effect on preventing osteoporosis via the miR-351-5p/IRS1 axis and mTOR/NFκB signaling pathway

This study aimed to investigate the antiosteoporotic effects and regulatory mechanisms of estradiol (E2) and vitamin D. MC3T3-E1 cells were treated with E2, vitamin D, or their combination, followed by a systematic assessment of cell proliferation and osteogenic differentiation capacity across the treatment groups. Subsequently, miRNA sequencing was performed to analyze differentially expressed miRNAs between the control and E2&vitamin D groups. The target relationship between miR-351-5p and IRS1 was validated, and the effects of the miR-351-5p/IRS1 axis on osteogenesis and mTOR/NFκB signaling pathway were determined after combination treatment. Additionally, an ovariectomized (OVX) osteoporosis mouse model was established to ‌systematically examine‌ the effects of E2, vitamin D, and their combination on osteoporosis and mTOR/NFκB signaling pathway. E2 and vitamin D synergistically promoted MC3T3-E1 cell proliferation and osteogenic differentiation. miR-351-5p was identified through miRNA sequencing analysis. miR-351-5p was downregulated in MC3T3-E1 cells after E2 and vitamin D combination treatment, and its overexpression partially reversed the effect of the combination treatment on osteogenesis. IRS1 was a target of miR-351-5p. When overexpressed, IRS1 partially mitigated the impact of miR-351-5p overexpression on osteogenesis and mTOR/NFκB signaling pathway under the combination treatment. Furthermore, in vivo experiments demonstrated that E2 and vitamin D could synergistically prevent osteoporosis in OVX mice by inhibiting the mTOR/NFκB signaling pathway. In conclusion, E2 and vitamin D exhibited a synergistic effect in preventing osteoporosis through the miR-351-5p/IRS1 axis and mTOR/NFκB signaling pathway. E2 and vitamin D combination treatment could be a potential anti-osteoporotic strategy for osteoporosis treatment.

Exploring the effects of hypoxia and reoxygenation time on hepatocyte apoptosis and inflammation

Hepatic Ischemia-Reperfusion Injury (HIRI) is an unavoidable pathological process during liver surgeries such as liver transplantation and hepatic resection, which involves a complex set of molecular and cellular mechanisms. The mechanisms of HIRI may involve a variety of biological processes in which inflammation and apoptosis play a central role. Therefore, it is crucial to deeply investigate the effects of different hypoxia and reoxygenation times on the construction of an in vitro model of hepatic ischemia-reperfusion injury. The human normal liver cell line HL-7702 IRI model was constructed by hypoxia chamber, and the inflammation and apoptosis focal levels of cells were detected by enzyme-linked immunosorbent assay, western blot and quantitative reverse transcription polymerase chain reaction. When 12-hour reoxygenation time was fixed, the inflammation and apoptosis indexes of HIRI model increased with the prolongation of hypoxia time (6, 12 and 24 hours). These indices reached highest level in the model group of 24-hour fixed hypoxia and 12-hour reoxygenation. Inflammation and apoptosis indices were significantly higher in the model group of 24-hours fixed hypoxia and 12-hours reoxygenation than in the group of 6 and 24 hours of reoxygenation. Taken together, the findings from this research demonstrated that during hypoxia phase, cells exhibited a clear time-dependent response of inflammation and cell death; on the contrary, during the reoxygenation phase, the cellular damage was not monotonically incremental, but showed an inverted U-shaped dynamic pattern. The present study reveals in depth the dynamic changes of cellular responses under hypoxia and reoxygenation conditions, providing us with an important theoretical basis to guide the selection and optimization of in vitro experimental models.

Unveiling the molecular complexity of intestinal ischemia-reperfusion injury through omics technologies

Intestinal ischemia-reperfusion injury (IR) is implicated in various clinical conditions and causes damage to the intestinal epithelium resulting in intestinal barrier loss. This presents a substantial clinical challenge, emphasizing the importance of gaining a comprehensive understanding of molecular events to aid in the identification of novel therapeutic targets. This review systematically explores the extent to which omics technologies-transcriptomics, proteomics, metabolomics, and metagenomics-have already contributed to deciphering the molecular mechanisms contributing to intestinal IR injury, in in vivo and in vitro animal and human models, and in clinical samples. Recent breakthroughs involve applying omics methodologies on exosomes, organoids, and single cells, shedding light on promising avenues and valuable targets to reduce intestinal IR injury. Future directions aimed at expediting clinical translation are discussed as well and include multi-omics data integration to facilitate the identification of key regulatory nodes driving intestinal IR injury and advancing human organoid models based on the novel insights by single-cell omics technologies, offering hope for clinical application of therapeutic strategies in the years to come.

The protective effects of phosphoserine aminotransferase 1 (PSAT1) against hepatic ischemia-reperfusion injury

Hepatic ischemia-reperfusion (I/R) injury is a severe clinical syndrome, causing a profound medical and socioeconomic burden worldwide. This study aimed to explore underlying biomarkers and treatment targets in the progression of hepatic I/R injury. We screened gene expression profiles of the hepatic I/R injury from the Gene Expression Omnibus (GEO) database, downloaded expression profiles data (GSE117066). Differentially expressed genes (DEGs) were identified through cluster of the PPI network, and enrichment pathways were conducted based on gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The bioinformatics analysis was used to identify biomarkers that alleviate hepatic I/R injury. Finally, the effects of hub gene were investigated by in vitro and in vivo experiments. A total of 162 DEGs (76 up-regulated and 86 down-regulated genes) were extracted between sham and I/R, and 248 DEGs (118 up-regulated and 130 down-regulated genes) were extracted between I/R and ischemic postconditioning (IPO). The cluster of the PPI network and maximal clique centrality (MCC) method of the common DEGs were performed to identify the phosphoserine aminotransferase 1 (PSAT1) as the potential gene for hepatic I/R injury. Then, the H-E, TUNEL and PCNA staining were indicated that the hepatic injury score was highest in I/R 6 h. The expression level of apoptosis-related proteins was consistent with the pathological results. Both gain- and loss-of-function assays demonstrated that hepatic I/R injury was alleviated by PSAT1. PSAT1 may play crucial roles in hepatic I/R injury and thus serves as a hub biomarker for hepatic I/R injury prognosis and individual-based treatment.

Novel circRNA-miRNA-mRNA networks regulated by maternal exercise in fetal hearts of pregestational diabetes

BACKGROUND

Maternal exercise lowers the incidence of congenital heart defects (CHDs) induced by pregestational diabetes. However, the molecular mechanisms underlying the beneficial effects of maternal exercise remain unclear. The present study aimed to identify circular RNA (circRNA), microRNA (miRNA) and mRNA networks that are regulated by maternal exercise in fetal hearts of pregestational diabetes.

METHODS

Pregestational diabetes was induced in adult C57BL/6 female mice by streptozotocin. The expression profiles of circRNAs, miRNAs and mRNAs in E10.5 fetal hearts of offspring of control and diabetic mothers with or without exercise were analyzed using next generation sequencing. circRNA-miRNA-mRNA networks in fetal hearts were mapped and key candidate transcripts were verified by qPCR analysis.

RESULTS

Pregestational diabetes dysregulated the expression of 206 circRNAs, 66 miRNAs and 391 mRNAs in fetal hearts. Maternal exercise differentially regulated 188 circRNAs, 57 miRNAs and 506 mRNAs in fetal hearts of offspring of pregestational diabetes. A total of 5 circRNAs, 12 miRNAs, and 28 mRNAs were incorporated into a final maternal exercise-associated regulatory network in fetal hearts of offspring of maternal diabetes. Notably, maternal exercise normalized the dysregulated circ_0003226/circ_0015638/miR-351-5p and circ_0002768/miR-3102-3p.2-3p pairs in fetal hearts of pregestational diabetes.

CONCLUSION

Maternal exercise reverses the dysregulated circ_0003226/circ_0015638/miR-351-5p and circ_0002768/miR-3102-3p.2-3p pairs, and partially normalizes circRNA, miRNA, and mRNA expression profiles in fetal hearts of pregestational diabetes. These findings shed new light on the potential mechanisms of the beneficial effects of maternal exercise on the developing heart in diabetic pregnancies.

The sirtuin family in health and disease

Sirtuins (SIRTs) are nicotine adenine dinucleotide(+)-dependent histone deacetylases regulating critical signaling pathways in prokaryotes and eukaryotes, and are involved in numerous biological processes. Currently, seven mammalian homologs of yeast Sir2 named SIRT1 to SIRT7 have been identified. Increasing evidence has suggested the vital roles of seven members of the SIRT family in health and disease conditions. Notably, this protein family plays a variety of important roles in cellular biology such as inflammation, metabolism, oxidative stress, and apoptosis, etc., thus, it is considered a potential therapeutic target for different kinds of pathologies including cancer, cardiovascular disease, respiratory disease, and other conditions. Moreover, identification of SIRT modulators and exploring the functions of these different modulators have prompted increased efforts to discover new small molecules, which can modify SIRT activity. Furthermore, several randomized controlled trials have indicated that different interventions might affect the expression of SIRT protein in human samples, and supplementation of SIRT modulators might have diverse impact on physiological function in different participants. In this review, we introduce the history and structure of the SIRT protein family, discuss the molecular mechanisms and biological functions of seven members of the SIRT protein family, elaborate on the regulatory roles of SIRTs in human disease, summarize SIRT inhibitors and activators, and review related clinical studies.

Hypoxic/Ischemic Inflammation, MicroRNAs and δ-Opioid Receptors: Hypoxia/Ischemia-Sensitive Versus-Insensitive Organs

Hypoxia and ischemia cause inflammatory injury and critically participate in the pathogenesis of various diseases in various organs. However, the protective strategies against hypoxic and ischemic insults are very limited in clinical settings up to date. It is of utmost importance to improve our understanding of hypoxic/ischemic (H/I) inflammation and find novel therapies for better prevention/treatment of H/I injury. Recent studies provide strong evidence that the expression of microRNAs (miRNAs), which regulate gene expression and affect H/I inflammation through post-transcriptional mechanisms, are differentially altered in response to H/I stress, while δ-opioid receptors (DOR) play a protective role against H/I insults in different organs, including both H/I-sensitive organs (e.g., brain, kidney, and heart) and H/I-insensitive organs (e.g., liver and muscle). Indeed, many studies have demonstrated the crucial role of the DOR-mediated cyto-protection against H/I injury by several molecular pathways, including NLRP3 inflammasome modulated by miRNAs. In this review, we summarize our recent studies along with those of others worldwide, and compare the effects of DOR on H/I expression of miRNAs in H/I-sensitive and -insensitive organs. The alternation in miRNA expression profiles upon DOR activation and the potential impact on inflammatory injury in different organs under normoxic and hypoxic conditions are discussed at molecular and cellular levels. More in-depth investigations into this field may provide novel clues for new protective strategies against H/I inflammation in different types of organs.

Noncoding RNAs in age-related cardiovascular diseases

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality in the adult population worldwide and represent a severe economic burden and public health concern. The majority of human genes do not code for proteins. However, noncoding transcripts play important roles in ageing that significantly increases the risk for CVDs. Noncoding RNAs (ncRNAs) are critical regulators of multiple biological processes related to ageing such as oxidative stress, mitochondrial dysfunction and chronic inflammation. NcRNAs are also involved in pathophysiological developments within the cardiovascular system including arrhythmias, cardiac hypertrophy, fibrosis, myocardial infarction and heart failure. In this review article, we cover the roles of ncRNAs in cardiovascular ageing and disease as well as their potential therapeutic applications in CVDs.

MicroRNA-26b-5p Targets DAPK1 to Reduce Intestinal Ischemia/Reperfusion Injury via Inhibition of Intestinal Mucosal Cell Apoptosis

BACKGROUND

Emerging evidence has suggested that miRNAs are important regulators of intestinal I/R injury, but their function in this context remains elusive.

AIMS

To evaluate the role of miR-26b-5p in intestinal I/R injury.

METHODS

We utilized in vivo murine models of intestinal I/R and in vitro Mode-K cell-based models of oxygen and glucose deprivation/reperfusion (OGD/R) to examine the function of miR-26b-5p in intestinal I/R injury. The expression of miR-26b-5p in intestinal mucosa and Mode-K cell was detected by RT-PCR. HE staining and Chiu's score were used to evaluate intestinal mucosa injury severity. Apoptosis was detected by TUNEL stain, flow cytometry, and western blot. TargetScan and StarBase prediction algorithms were applied to predict putative target genes of miR-26b-5p and validated by luciferase reporter analyses.

RESULTS

We found that the expression of miR-26b-5p in intestinal mucosa was markedly decreased during I/R injury. We additionally found miR-26b-5p overexpression to markedly disrupt intestinal I/R- or OGD/R-induced injury in vivo and in vitro, whereas inhibiting this miRNA had an adverse impact and resulted in increased intestinal tissue injury and Mode-K cell damage. From a mechanistic perspective, miR-26b-5p was predicted to target DAPK1, which was related to cellular apoptosis. Luciferase reporter assay results confirmed that miR-26b-5p directly targets DAPK1 in Mode-K cells, thereby suppressing OGD/R-induced cell apoptosis.

CONCLUSION

Our findings show that miR-26b-5p may prevent intestinal I/R injury via targeting DAPK1 and inhibiting intestinal mucosal cell apoptosis, suggesting that this miRNA may be a viable target for the treatment of intestinal I/R injury.

Cystic fibrosis transmembrane conductance regulator prevents ischemia/reperfusion induced intestinal apoptosis via inhibiting PI3K/AKT/NF-κB pathway

BACKGROUND

Intestinal ischemia/reperfusion (I/R) injury is a fatal syndrome that occurs under many clinical scenarios. The apoptosis of intestinal cells caused by ischemia can cause cell damage and provoke systemic dysfunction during reperfusion. However, the mechanism of I/R-induced apoptosis remains unclear. Cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-activated chloride channel. Few researchers have paid attention to its role in intestinal I/R injury, or the relationship between CFTR and intestinal apoptosis induced by hypoxia/reoxygenation (H/R).

AIM

To investigate the effects of CFTR on I/R-induced intestinal apoptosis and its underlying molecular mechanisms.

METHODS

An intestinal I/R injury model was established in mice with superior mesenteric artery occlusion, and Caco2 cells were subjected to H/R for the simulation of I/R in vivo.

RESULTS

The results suggested that CFTR overexpression significantly increased the Caco2 cell viability and decreased cell apoptosis induced by the H/R. Interestingly, we found that the translocation of p65, an NF-κB member, from the cytoplasm to the nucleus after H/R treatment can be reversed by the overexpression of CFTR, the NF-κB P65 would return from the nucleus to the cytoplasm as determined by immunostaining. We also discovered that CFTR inhibited cell apoptosis in the H/R-treated cells, and this effect was significantly curbed by the NF-κB activator BA, AKT inhibitor GSK690693 and the PI3K inhibitor LY294002. Moreover, we demonstrated that CFTR overexpression could reverse the decreased PI3K/AKT expression induced by the I/R treatment in vivo or H/R treatment in vitro.

CONCLUSION

The results of the present study indicate that the overexpression of CFTR protects Caco2 cells from H/R-induced apoptosis; furthermore, it also inhibits H/R-induced apoptosis through the PI3K/AKT/NF-κB signaling pathway in H/R-treated Caco2 cells and intestinal tissues.

Oxidative Stress in Intestinal Ischemia-Reperfusion

Ischemia-reperfusion (I/R) injury is a manifestation of tissue or organ damage that is followed by ischemia and exacerbated by the return of blood flow to a previously damaged tissue or organ. The intestines are one of the most sensitive tissues and organs to I/R injury. Moreover, the adverse consequences of intestinal I/R (II/R) injury are not limited to the intestine itself and can also lead to damage of the distant tissues and organs. The mechanism of II/R is extremely complex and oxidative stress is the key link in the pathogenesis of II/R injury. This study summarizes the roles of oxidative stress and its signaling pathways involved in II/R. The signaling pathways that mitigate II/R injury include the nuclear factor erythroid-related factor 2 (Nrf2)-mediated signaling pathway, Wnt/β-catenin pathway, and phosphatidylinositol kinase 3 (PI3K)/Akt pathway; those that aggravate II/R injury include the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, Toll-like receptor (TLR) receptor-mediated signaling pathway, protein kinase CβII (PKCβII)/p66shc pathway, and microRNA (miRNA)/p66shc pathway; the effect of miRNA on related pathways and mitochondrial DNA translocation. The aforementioned pathways provide new ideas for further exploring the occurrence and development of II/R and more effective treatments for II/R injury.

miR‑351‑5p aggravates lipopolysaccharide‑induced acute lung injury via inhibiting AMPK

Inflammation and oxidative stress have indispensable roles in the development of acute lung injury (ALI). MicroRNA (miRNA/miR)‑351‑5p was initially identified as a myogenesis‑associated miRNA; however, its role in lipopolysaccharide (LPS)‑induced ALI remains unclear. The aim of the present study was to investigate the role and potential mechanisms of miR‑351‑5p in ALI. ALI was induced through a single intratracheal injection of LPS for 12 h, and miR‑351‑5p agomir, antagomir or their corresponding negative controls were injected into the tail vein before LPS stimulation. Compound C, 2',5'‑dideoxyadenosine and H89 were used to inhibit AMP‑activated protein kinase (AMPK), adenylate cyclase and protein kinase A (PKA), respectively. miR‑351‑5p levels in the lungs were significantly increased in response to LPS injection. miR‑351‑5p antagomir alleviated, while miR‑351‑5p agomir aggravated LPS‑induced oxidative stress and inflammation in the lungs. The present results also demonstrated that miR‑351‑5p antagomir attenuated LPS‑induced ALI via activating AMPK, and that the cAMP/PKA axis was required for the activation of AMPK by the miR‑351‑5p antagomir. In conclusion, the present study indicated that miR‑351‑5p aggravated LPS‑induced ALI via inhibiting AMPK, suggesting that targeting miR‑351‑5p may help to develop efficient therapeutic approaches for treating ALI.

MicroRNA files in the prevention of intestinal ischemia/reperfusion injury by hydrogen rich saline

Background: Hydrogen-rich saline (HRS) has been proven effective against ischemia/reperfusion (I/R) injury. However, knowledge on the underlying signaling events remain poor. Having recent highlight of microRNAs (miRNAs) in mediating intestinal I/R injury, we hypothesized that HRS may protect intestine against I/R injury by regulating miRNAs.

Method: Mice were given intraperitoneal injection of saline or HRS once daily for five consecutive days before undergoing intestinal I/R that was induced by 60-min ischemia followed by 180-min reperfusion of superior mesenteric artery. The intestine was collected for histopathological assay, miRNA microarray profiling, Real-Time PCR, and Western blotting. Next, miR-199a-3p mimics or inhibitors were transfected into IEC-6 cells to explore the relationship between HRS treatment and miR-199a-3p.

Results: I/R-induced mucosal injury and epithelial cells apoptosis were attenuated by HRS pretreatment. A total of 64 intestinal I/R-responsive miRNAs were altered significantly by HRS pretreatment, in which we validated four novel miRNAs with top significance by Real-Time PCR, namely miR-199a-3p, miR-296-5p, miR-5126, and miR-6538. Particularly, miR-199a-3p was drastically increased by I/R but reduced by HRS. Computational analysis predicts insulin-like growth factor (IGF)-1, mammalian target of rapamycin (mTOR), and phosphoinositide-3-kinase (PI3K) regulatory subunit 1 as targets of miR-199a-3p, suggesting involvement of the pro-survival pathway, IGF- 1/PI3K/Akt/mTOR. In in vitro experiment, HRS treatment reduced miR-199a-3p level, increase IGF-1, PI3K and mTOR mRNA expression, restore IEC-6 cells viability, and this protective effects were reversed under miR-199a-3p mimics treatment.

Conclusion: Collectively, miR-199a-3p may serve a key role in the anti-apoptotic mechanism of HRS that contributes to its protection of the intestine against I/R injury.

Long non-coding RNAs: A double-edged sword in aging kidney and renal disease

Aging as one of intrinsic biological processes is a risk factor for many chronic diseases. Kidney disease is a global problem and health care burden worldwide. The diagnosis of kidney disease is currently based on serum creatinine and urea levels. Novel biomarkers may improve diagnostic accuracy, thereby allowing early prevention and treatment. Over the past few years, advances in genome analyses have identified an emerging class of noncoding RNAs that play critical roles in the regulation of gene expression and epigenetic reprogramming. Long noncoding RNAs (lncRNAs) are pervasively transcribed in the genome and could bind DNA, RNA and protein. Emerging evidence has demonstrated that lncRNAs played an important role in all stages of kidney disease. To date, only some lncRNAs were well identified and characterized, but the complexity of multilevel regulation of transcriptional programs involved in these processes remains undefined. In this review, we summarized the lncRNA expression profiling of large-scale identified lncRNAs on kidney diseases including acute kidney injury, chronic kidney disease, diabetic nephropathy and kidney transplantation. We further discussed a number of annotated lncRNAs linking with complex etiology of kidney diseases. Finally, several lncRNAs were highlighted as diagnostic biomarkers and therapeutic targets. Targeting lncRNAs may represent a precise therapeutic strategy for progressive renal fibrosis.

Transfer of microRNA-25 by colorectal cancer cell-derived extracellular vesicles facilitates colorectal cancer development and metastasis

Cancer cell-derived extracellular vesicles (EVs) have been reported to promote the progression of colorectal cancer (CRC), although the regulatory mechanism remains uncharacterized. In this study, we investigated the role of microRNA-25 (miR-25)/sirtuin 6 (SIRT6) in the contribution of EVs derived from CRC cells to progression of CRC. In a co-culture system with EVs from HCT116 and NCM460 cells, the viability, migratory, and invasive properties of SW480 and SW620 cells were evaluated by cell counting kit-8 (CCK-8) and Transwell assays. Luciferase, chromatin immunoprecipitation (ChIP), and RNA immunoprecipitation (RIP) assays were conducted to verify the interaction among miR-25, SIRT6, lin-28 homologB (Lin28b), and neuropilin-1 (NRP-1). It was established that HCT116 cell-derived EVs promoted the malignant properties of SW480 cells and SW620 cells by delivering miR-25. SIRT6 was targeted by miR-25, whereas SIRT6 inhibited NRP-1 through downregulation of Lin28b. The tumor-bearing nude mouse experiments substantiated that HCT116 cell-derived EVs transferred miR-25 to facilitate tumor formation and metastasis by inhibiting SIRT6. In summary, our study clarifies the involvement of miR-25-targeted SIRT6 inhibition and SIRT6-mediated inhibition of the Lin28b/NRP-1 axis in CRC cell-derived EVs to CRC progression and metastasis.

Emerging roles of microRNAs in intestinal ischemia/reperfusion-induced injury: a review

Intestinal ischemia/reperfusion (II/R) injury is a serious pathological phenomenon in underlying hemorrhagic shock, trauma, strangulated intestinal obstruction, and acute mesenteric ischemia which associated with high morbidity and mortality. MicroRNAs (miRNAs, miRs) are endogenous non-coding RNAs that regulate post-transcriptionally target mRNA translation via degrading it and/or suppressing protein synthesis. This review discusses on the role of some miRNAs in underlying II/R injury. Some of these miRNAs can have protective action through agomiR or specific antagomiR, and others can have destructive effects in the basal level of II/R insult. Based on these literature reviews, II/R injury affects several miRNAs and their specific target genes. Some miRNAs upregulate under condition of II/R injury, and multiple miRNAs downregulate following II/R damage. Data of this review have been collected from the scientific articles published in databases such as Science Direct, Scopus, PubMed, Web of Science, and Scientific Information Database from 2000 to 2020. It is shown a correlation between changes in the expression of miRNAs and autophagy, inflammation, oxidative stress, apoptosis, and epithelial barrier function. Taken together, agomiR or antagomiR of some miRNAs can be considered as one new target for the research and development of innovative drugs to the prevention or treatment of II/R damage.

MiR-23a-5p exacerbates intestinal ischemia-reperfusion injury by promoting oxidative stress via targeting PPAR alpha

MiR-23a-5p is involved in the occurrence and development of some serious diseases, but its effects on intestinal ischemia-reperfusion (II/R) injury is unclear. In this research, the hypoxia/reoxygenation (H/R) model on IEC-6 cells and II/R model in mice were used. The data showed that the ROS level in model group was significantly increased compared with control group. The level of intestinal MPO was increased and serum SOD was decreased in mice compared with sham group. Moreover, the expression levels of miR-23a-5p in model groups were obviously increased in vitro and in vivo, while the expression levels of PPARα, FOXO3α, PGC-1α, Nrf2, CAT, NQO1, HO-1 and SOD2 were significantly decreased. The double luciferase reporter gene assay showed that there was binding site between miR-23a-5p and PPARα. When miR-23a-5p was inhibited or PPARα gene was overexpressed, H/R-caused cell damage was alleviated and ROS level was decreased compared with NC group. PPARα expression level was increased, accompanied by the increased levels of FOXO3α, PGC-1α, Nrf2, CAT, NQO1, HO-1 and SOD2. After enhancing miR-23a-5p expression or silencing PPARα gene, H/R-caused cell damage was further aggravated compared with NC group, and ROS level was increased associated with the decreased levels of FOXO3α, PGC-1α, Nrf2, CAT, NQO1, HO-1 and SOD2. Our study demonstrated that miR-23a-5p exacerbated II/R injury by promoting oxidative stress via targeting PPARα, which should be considered as one new drug target to treat II/R injury.

The roles of microRNA in redox metabolism and exercise-mediated adaptation

MicroRNAs (miRs) are small regulatory RNA transcripts capable of post-transcriptional silencing of mRNA messages by entering a cellular bimolecular apparatus called RNA-induced silencing complex. miRs are involved in the regulation of cellular processes producing, eliminating or repairing the damage caused by reactive oxygen species, and they are active players in redox homeostasis. Increased mitochondrial biogenesis, function and hypertrophy of skeletal muscle are important adaptive responses to regular exercise. In the present review, we highlight some of the redox-sensitive regulatory roles of miRs.

MicroRNA-874-3p Aggravates Doxorubicin-Induced Renal Podocyte Injury via Targeting Methionine Sulfoxide Reductase B3

Clinical application of doxorubicin (Dox) is limited due to its serious side effects including nephrotoxicity, and kidney podocytes play important roles in renal diseases. MicroRNAs (miRNAs) are critical regulators associated with human diseases. The purpose of this study was to explore a novel target in adjusting Dox-induced renal podocyte injury. Through a double luciferase reporter gene experiment, it was found that miR-874-3p directly targeted methionine sulfoxide reductase B3 (MsrB3). During the tests of miR-874-3p inhibitor and MsrB3 siRNA in human podocytes or miR-874-3p antagomir in mice, we found that the expression levels of downstream oxidative stress and apoptosis-related proteins were regulated by miR-874-3p/MsrB3 signal to alleviate or aggravate renal podocyte injury. The data in the present work showed that miR-874-3p aggravated Dox-caused renal podocyte injury by promoting apoptosis and oxidative damage via inhibiting MsrB3. Therefore, miR-874-3p/MsrB3 should be considered as a new therapeutic target in controlling renal podocyte injury induced by Dox.

Sirtuin 6 protects human retinal pigment epithelium cells from LPS-induced inflammation and apoptosis partly by regulating autophagy

Lipopolysaccharides (LPS)-induced retinal inflammation is an important factor in retinal diseases. This study was aimed to investigate the effect of Sirt6 on LPS-induced retinal injury. ARPE-19 cells were incubated with LPS to induce inflammation. The cell viability was determined using CCK-8 assay. The mRNA level and protein expression of corresponding genes was detected using qRT-PCR and western blot, respectively. The production of inflammatory cytokines was measured using ELISA kit. The levels of oxidative stress-related factors were measured using their detection kits. Cell apoptosis was observed using TUNEL assay. The results showed that Sirt6 was downregulated after LPS treatment. Sirt6 strengthened LPS-induced autophagy by promoting the expression of LC3II/I, beclin1 and ATG5. Sirt6 treatment significantly inhibited LPS-induced inflammation, oxidative stress and cell apoptosis, which was then partly abolished by 3 MA. These results suggest Sirt6 to be an important regulator for LPS-induced inflammation, oxidative stress, and apoptosis partly by regulating cell autophagy.

MicroRNA-142-3p attenuates hepatic ischemia/reperfusion injury via targeting of myristoylated alanine-rich C-kinase substrate

MiR-142-3p as one key molecule in oncogenesis and inflammation plays crucial roles in hepatic fibrosis, hepatocellular carcinoma and other liver disease. However, there have no literatures to report its effects on hepatic ischemia-reperfusion (HI/R) injury. In the present work, hypoxia reoxygenation (H/R) models on AML12 and HepG2 cells, and ischemia/reperfusion model in mice were established. The methods of real-time PCR, dual luciferase reporter, mimic, inhibitor, agomir, antagomir and siRNA transfection assays were used. The expression levels of miR-142-3p were decreased in model groups in vitro and in vivo compared with control group or Sham group, which directly targeted MARCKS to regulate its expression. Then, MARCKS activated p38/JNK signal, up-regulated NF-κB expression to accelerate inflammation, and inhibited PI3K/AKT signal to promote apoptosis. Moreover, miR-142-3p mimic in vitro and agomir in vivo lowered the expression levels of MARCKS, thereby alleviating apoptosis and inflammation to relieve HI/R injury. Furthermore, miR-142- 3p inhibitor in vitro and antagomir in vivo up-regulated the expression levels of MARCKS to aggravate HI/R damage via promoting inflammation and apoptosis. Consistently, MARCKS siRNA markedly inhibited HI/R injury by restraining apoptosis and inflamm- ation in mice. MiR-142-3p played a considerable part in adjusting HI/R injury by targeting MARCKS, and miR-142-3p/MARCKS should be a new therapeutic target for HI/R injury.

The Therapeutic Potential of Breast Milk-Derived Extracellular Vesicles

In the past few decades, interest in the therapeutic benefits of exosomes and extracellular vesicles (EVs) has grown exponentially. Exosomes/EVs are small particles which are produced and exocytosed by cells throughout the body. They are loaded with active regulatory and stimulatory molecules from the parent cell including miRNAs and enzymes, making them prime targets in therapeutics and diagnostics. Breast milk, known for years to have beneficial health effects, contains a population of EVs which may mediate its therapeutic effects. This review offers an update on the therapeutic potential of exosomes/EVs in disease, with a focus on EVs present in human breast milk and their remedial effect in the gastrointestinal disease necrotizing enterocolitis. Additionally, the relationship between EV miRNAs, health, and disease will be examined, along with the potential for EVs and their miRNAs to be engineered for targeted treatments.

MicroRNA-29b-3p reduces intestinal ischaemia/reperfusion injury via targeting of TNF receptor-associated factor 3

BACKGROUND AND PURPOSE

The microRNA miR-29b-3p shows important roles in regulating apoptosis and inflammation. However, its effects on intestinal ischaemia/reperfusion (II/R) injury have not been reported. Here we have investigated the functions of miR-29b-3p on II/R injury on order to find drug targets to treat the injury.

EXPERIMENTAL APPROACH

Two models - in vitro hypoxia/reoxygenation (H/R) of IEC-6 cells; in vivo, II/R injury in C57BL/6 mice were used. Western blotting and dual-luciferase reporter assays were used and mimic and siRNA transfection tests were applied to assess the effects of miR-29b-3p on II/R injury via targeting TNF receptor-associated factor 3 (TRAF3).

KEY RESULTS

The H/R procedure decreased cell viability and promoted inflammation and apoptosis in IEC-6 cells, and the II/R procedure also promoted intestinal inflammation and apoptosis in mice. Expression levels of miR-29b-3p were decreased in H/R-induced cells and II/R-induced intestinal tissues of mice compared with control group or sham group, which directly targeted TRAF3. Decreased miR-29b-3p level markedly increased TRAF3 expression via activating TGF-α-activated kinase 1 phosphorylation, increasing NF-κB (p65) levels to promote inflammation, up-regulating Bcl2-associated X expression, and down-regulating Bcl-2 expression to trigger apoptosis. In addition, the miR-29b-3p mimetic and TRAF3 siRNA in IEC-6 cells markedly suppressed apoptosis and inflammation to alleviate II/R injury via inhibiting TRAF3 signallimg.

CONCLUSIONS AND IMPLICATIONS

The miR-29b-3p played a critical role in II/R injury, via targeting TRAF3, which should be considered as a significant drug target to treat the disease.

SIRT6 abrogation promotes adrenocortical carcinoma through activation of NF-κB signaling

As an uncommon malignancy in the adrenal gland, adrenocortical carcinoma (ACC) is characterized by thorny diagnosis and poor clinical outcome, necessitating innovative treatment strategies. Sirtuin 6 (SIRT6), a tumor suppressor, modulates aerobic glycolysis of malignant cells and has an impact on tumorigenesis. This study focused on investigating SIRT6 expression in ACC and how it generates cancer phenotypes. SIRT6 expression was inhibited in ACC tissues according to western blotting, real-time polymerase chain reaction, and immunohistochemistry. MTT assay, TUNEL assay, and flow cytometry were performed to evaluate the contribution of SIRT6 to cell invasion, proliferation, death, and migration. It was shown that SIRT6 knockdown promoted cell invasion, proliferation, and migration, and inhibited cell death. Moreover, it was found that SIRT6 knockdown upregulated TLR4 and reinforced phosphorylation of the nuclear transcription factor-kappa B (NF-κB) subunit p65 as well as inhibitor of nuclear factor kappa-B kinase. Additionally, SIRT6 knockdown significantly enhanced expression of calcitonin gene-related peptide as well as transient receptor potential vanilloid subtype 1. It also reinforced reactive oxygen species generation. Overall, our research findings demonstrate that SIRT6 serves as a tumor suppressor via regulation of the NF-κB pathway, which could offer an innovative strategy to treat ACC.

Dioscin ameliorates intestinal ischemia/reperfusion injury via adjusting miR-351-5p/MAPK13-mediated inflammation and apoptosis

Inflammatory reaction and cell apoptosis are two important processes in intestinal ischemia/reperfusion (II/R) injury, and exploration of effective lead compounds against II/R injury via regulating inflammation and apoptosis is critical important. In this paper, the results indicated that dioscin significantly increased cell viability, and inhibited inflammation and apoptosis caused by hypoxia-reoxygenation (H/R) injury in IEC-6 cells. in vivo II/R injury, dioscin markedly suppressed inflamma- tion and apoptosis, improved pathological changes, and depressed chiu' score in rats. Mechanistic studies indicated that dioscin notably up-regulated the expression level of MAPK13 through decreasing miR-351-5p level, and thereby decreased the expression levels of p-PKD1, NF-κB, Apaf-1, cleaved Caspase-3 and cleaved Caspase-9. Furthermore, miR-351-5p mimic and inhibitor experiments in IEC-6 cells further proved that dioscin up-regulated MAPK13 expression by decreasing miR-351-5p level to inhibit inflammation and apoptosis. Therefore, dioscin showed protective effect against II/R injury via adjusting miR-351-5/MAPK13-mediated inflammation and apoptosis. Dioscin should be considered as one potent candidate and miR-351-5/ MAPK13 should be one effective drug target for the treatment of II/R injury.

MicroRNA351 targeting TRAF6 alleviates dexamethasone-induced myotube atrophy

BACKGROUND

Glucocorticoids, including dexamethasone (Dex), are corticosteroids secreted by the adrenal gland, which are used as potent anti-inflammatory, anti-shock, and immunosuppressive agents. Dex is commonly used in patients with malignant tumors, such lung cancer. However, administration of high-dose Dex induces severe atrophy of the skeletal muscle, and the underlying mechanisms of this skeletal muscle atrophy remain unclear. Abundant miRNAs of skeletal muscle, such as miR-351, play an important role in the regulation of extenuating the process of muscle atrophy.

METHODS

The mRNA and protein expression of TRAF6, MuRF1, MAFbx was determined by real-time PCR and western blot, while the expression of miR-351 was detected by real-time PCR. The myotubes were transfected with miR-351 mimic, negative control, or miR-351 inhibitor. The C2C12 myotubes diameter was measured.

RESULTS

MicroRNA351 (miR-351) level was markedly reduced and the mRNA and protein levels of tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) were increased in Dex-induced C2C12 myotube atrophy. miR-351 directly interacted with the 3'-untranslated region (3'UTR) of TRAF6. Interestingly, miR-351 administration notably inhibited the reduction of the C2C12 myotube diameter induced by Dex treatment and reduced the levels of TRAF6, muscle-RING-finger protein-1 (MuRF1), and muscle atrophy F-box (MAFbx).

CONCLUSIONS

miR-351 counteracts Dex-induced C2C12 myotube atrophy by repressing the TRAF6 expression as well as E3 ubiquitin ligase MuRF1 and MAFbx. miR-351 maybe a potential target for development of a new strategy for skeletal muscle atrophy.

Protective effect of dioscin against intestinal ischemia/reperfusion injury via adjusting miR-351-5p-mediated oxidative stress

Oxidative stress plays important roles in intestinal ischemia-reperfusion (II/R) injury, and exploration of effective lead compounds against II/R injury via regulating oxidative stress is necessary. In this study, the effects and possible mechanisms of dioscin against hypoxia-reoxygenation (H/R) injury in IEC-6 cells and II/R injury in mice were investigated. The results showed that dioscin markedly increased cell viability, and reduced ROS level caused by H/R injury in IEC-6 cells. in vivo, dioscin significantly reduced the levels of MDA, MPO and chiu' score, increased SOD level, and improved pathological changes caused by II/R injury in mice. Mechanism investigation showed that dioscin markedly up-regulated the expression levels of Sirt6 by decreasing miR-351-5p levels, decreased the expression levels of p-FoxO3α via activating AMPK, and increased the expression levels of MnSOD and CAT. In addition, miR-351-5p mimic in IEC-6 cells and agomir in mice increased ROS levels and aggravated II/R injury. MiR-351-5p inhibitor in IEC-6 cells and antagomir in mice alleviated these actions by adjusting Sirt6 signal pathway. MiR-351-5p interference experiment further confirmed that dioscin increased Sirt6 expression level by down- regulating miR-351-5p level to inhibit oxidative stress and reduce II/R injury. Furthermore, we also demonstrated that dioscin inhibited the expression level of miR-351-5p via reducing TRBP expression level during the generation of miR-351-5p mature body. Dioscin showed protective effect against II/R injury via adjusting miR- 351-5/Sirt6 signal to reduce oxidative stress, which should be considered as one potent candidate to treat II/R injury. In addition, miR-351-5/Sirt6 could be one effective drug target against II/R injury.

MicroRNA-351-5p aggravates intestinal ischaemia/reperfusion injury through the targeting of MAPK13 and Sirtuin-6

BACKGROUND AND PURPOSE

Intestinal ischaemia-reperfusion (II/R) injury is a serious clinical problem. Here we have investigated novel mechanisms and new drug targets in II/R injury by searching for microRNAs regulating such injury.

EXPERIMENTAL APPROACH

We used hypoxia/reoxygenation (H/R) of IEC-6 cell cultures and models of II/R models in rats and mice. Microarray assays were used to identify target miRNAs from rat intestinal. Real-time PCR, Western blot and dual luciferase reporter assays, and agomir and antagomir in vitro and in vivo were used to assess the effects of the target miRNA on II/R injury.

KEY RESULTS

The miR-351-5p was differentially expressed in our models and it targeted MAPK13 and sirtuin-6. This miRNA reduced levels of sirtuin-6 and AMP-activated protein kinase phosphorylation, and activated forkhead box O3 (FoxO3α) phosphorylation to cause oxidative stress. Also, miR-351-5p markedly reduced MAPK13 level, activated polycystic kidney disease 1/NF-κB signal and increased NF-κB (p65). Moreover, miR-351-5p up-regulated levels of Bcl2-associated X, cytochrome c, apoptotic peptidase activating factor 1, cleaved-caspase 3 and cleaved-caspase 9 by reducing sirtuin-6 levels to promote apoptosis. In addition, miR-351-5p mimic in IEC-6 cells and agomir in mice aggravated these effects, and miR-351-5p inhibitor and antagomir in mice alleviated these actions.

CONCLUSIONS AND IMPLICATIONS

Our data showed that miR-351-5p aggravated II/R injury by promoting intestinal mucosal oxidative stress, inflammation and apoptosis by targeting MAPK13 and sirtuin-6.These data provide new insights into the mechanisms regulating II/R injury, and of miR-351-5p could be considered as a novel therapeutic target for such injury.