[Physiological response to drought stress and drought resistance of six Helleborus orientlis cultivars]. / å ­ä¸ªä¸œæ–¹é“ç­·å­å“ç§å¯¹å¹²æ—±èƒè¿«çš„ç”Ÿç†å“åº”åŠæŠ—æ—±æ€§è¯„ä»·.

We examined the responses of physiological and leaf anatomic structural characteristics of six Helleborus orientalis cultivars to different degrees of drought stress. A membership function was used to evaluate drought resis-tance and identify physiological and leaf anatomical indicators that exhibited a stronger correlation with drought tolerance. The results showed that leaf thickness, leaf area per unit mass and soluble protein levels of the six cultivars significantly decreased with the increases of drought stress. Net photosynthetic rate, stomatal conductance, and transpiration rate of leaves increased first and then decreased, while the intercellular CO2 concentration decreased. The relative electrical conductivity, MDA, and H2O2 contents of leaves were increased. Soluble saccharide and proline contents, and antioxidant enzyme activities were first elevated and then decreased. With the increases of drought stress, the ratio of palisade tissue thickness to sponge tissue thickness and stomatal density increased. Key indicators and relativities in evaluating drought resistance of those cultivars were proline, soluble sugars, and the ratio of palisade tissue thickness to sponge tissue thickness. H. orientalis 'Anemone Red' and H. orientalis 'Ane-mone Red spotted' had better drought resistance, which could be the excellent parental materials for the cultivation of new drought-resistant cultivars in the future.

MiR-125b and SATB1-AS1 might be shear stress-mediated therapeutic targets.

The aim of the study was to explore the potential molecular mechanism associated with shear stress on abdominal aortic aneurysm (AAA) progression. This study performed RNA sequencing on AAA patients (SQ), AAA patients after endovascular aneurysm repair (EVAR, SH), and normal controls (NC). Furthermore, we identified the differentially expressed microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNA (cirRNAs) and constructed competing endogenous RNA (ceRNA) networks. Finally, 164 differentially expressed miRNAs, 179 co-differentially expressed lncRNAs, and 440 co-differentially expressed circRNAs among the three groups were obtained. The differentially expressed miRNAs mainly enriched in 325 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Target genes associated with co-differentially expressed genes among the group of SH, SQ, and NC mainly enriched in 66 KEGG pathways. LncRNA-miRNA-mRNA interactions, including 15 lncRNAs, 63 miRNAs and 57 mRNAs, was constructed. CircRNA-miRNA-mRNA ceRNA network included 79 circRNAs, 21 miRNAs, and 49 mRNAs. Among them, KLRC2 and CSTF1, targeted by miR-125b, participated in cell-mediated immunity regulation. MiR-320-related circRNAs and SATB1-AS1 serving as the sponge of miRNAs, such as has-circ-0129245, has-circ-0138746, and has-circ-0139786, were hub genes in ceRNA network. In conclusion, AAA patients might be benefit from EVAR based on various pathways and some molecules, such as miR-125b and SATB1-AS1, related with shear stress.

The R2R3MYB transcription factors MaMYBF and MaMYB1 regulate flavonoid biosynthesis in grape hyacinth.

R2R3 MYBs play vital roles in the regulation of flavonoid biosynthesis. However, the regulatory network of R2R3 MYBs in flavonoid biosynthesis is not fully understood in grape hyacinth (Muscari spp.). Here, we identified two R2R3 MYBs, MaMYBF and MaMYB1, as potential regulators of flavonol and anthocyanin biosynthesis, respectively. MaMYBF and MaMYB1 expression was elevated during flower development and was light-induced, and the expression patterns were related to those of the flavonoid structural genes MaFLS and MaDFR, respectively. The BiFC assay verified that MaMYB1 interacts with MabHLH1, but MaMYBF does not. A dual luciferase assay revealed that MaMYBF alone strongly activated pMaFLS, and its activation was attenuated at reduced doses of MaMYBF in the presence of MabHLH1, MaMybA, and MaMYB1. MaDFR transcription mediated by MaMybA and MabHLH1 was inhibited by MaMYB1. Moreover, overexpression of MaMYBF and MaMYB1 in tobacco reduced flower pigmentation and repressed the expression of flavonoid pathway key structural genes. Therefore, MaMYBF regulates the flavonol pathway independently of cofactors. Whereas MaMYB1 regulates anthocyanin biosynthesis by binding to MabHLH1 and disrupting the MaMybA-bHLH complex in grape hyacinth. Our results offer new insights into the intricate regulatory network of flavonoids in grape hyacinth involving the regulation of both flavonol and anthocyanin.

lncRNA ANRIL accelerates wound healing in diabetic foot ulcers via modulating HIF1A/VEGFA signaling through interacting with FUS.

BACKGROUND: Diabetic foot ulcer (DFU) is a frequently diagnosed complication of diabetes, and remains a heathcare burden worldwide. However, the pathogenesis of DFU is still largely unclear. The objective of this study is to delineate the function and underlying mechanism of lncRNA antisense non coding RNA in the INK4 locus (ANRIL) in endothelial progenitor cells (EPCs) and DFU mice. METHODS: The DFU mouse model was established, and EPCs were subjected to high glucose (HG) treatment to mimic diabetes. qRT-PCR or western blot was employed to detected the expression of ANRIL, HIF1A, FUS and VEGFA. CCK-8 and Annexin V/PI staining were used to monitor cell proliferation and apoptosis. Wound healing, Transwell invasion and tube formation assays were conducted to assess cell migration, invasion and angiogenesis, respectively. The association between ANRIL and FUS was verified by RNA pull-down and RIP assays. Luciferase and ChIP assays were employed to investigate HIF1A-mediated transcriptional regulation of VEGFA and ANRIL. The histological alterations of DFU wound healing were observed by H&E and Masson staining. RESULTS: ANRIL was downregulated in peripheral blood samples of DFU patients, DFU mice and HG-treated EPCs. Mechanistically, ANRIL regulated HIFA mRNA stability via recruiting FUS. VEGFA and ANRIL were transcriptionally regulated by HIF1A. Functional experiments revealed that HG suppressed EPC proliferation, migration, invasion and tube formation, but promoted apoptosis via ANRIL/HIF1A axis. ANRIL accelerated DFU wound healing via modulating HIF1A expression in vivo. CONCLUSION: ANRIL accelerated wound healing in DFU via modulating HIF1A/VEGFA signaling in a FUS-dependent manner.

Two B-Box Proteins, MaBBX20 and MaBBX51, Coordinate Light-Induced Anthocyanin Biosynthesis in Grape Hyacinth.

Floral colour is an important agronomic trait that influences the commercial value of ornamental plants. Anthocyanins are a class of flavonoids and confer diverse colours, and elucidating the molecular mechanisms that regulate their pigmentation could facilitate artificial manipulation of flower colour in ornamental plants. Here, we investigated the regulatory mechanism of light-induced anthocyanin biosynthesis during flower colouration in grape hyacinth (Muscari spp.). We studied the function of two B-box proteins, MaBBX20 and MaBBX51. The qPCR revealed that MaBBX20 and MaBBX51 were associated with light-induced anthocyanin biosynthesis. Both MaBBX20 and MaBBX51 are transcript factors and are specifically localised in the nucleus. Besides, overexpression of MaBBX20 in tobacco slightly increased the anthocyanin content of the petals, but reduced in MaBBX51 overexpression lines. The yeast one-hybrid assays indicated that MaBBX20 and MaBBX51 did not directly bind to the MaMybA or MaDFR promoters, but MaHY5 did. The BiFC assay revealed that MaBBX20 and MaBBX51 physically interact with MaHY5. A dual luciferase assay further confirmed that the MaBBX20-MaHY5 complex can strongly activate the MaMybA and MaDFR transcription in tobacco. Moreover, MaBBX51 hampered MaBBX20-MaHY5 complex formation and repressed MaMybA and MaDFR transcription by physically interacting with MaHY5 and MaBBX20. Overall, the results suggest that MaBBX20 positively regulates light-induced anthocyanin biosynthesis in grape hyacinth, whereas MaBBX51 is a negative regulator.

MiR-137 regulates low-intensity shear stress-induced human aortic endothelial cell apoptosis via JNK/AP-1 signaling.

The objective of this study is to evaluate the role of miR-137 in low-intensity shear stress-induced endoplasmic reticulum (ER) stress and cell apoptosis in human aortic endothelial cells (HAECs). HAECs were transfected with miR-137 mimic, miR-137 inhibitor, or the corresponding negative control and then exposed to pulsatile shear stress in a parallel-plate flow chamber at 1, 2, 5, 10, and 15 dyn/cm2 for 3 h. Real-time polymerase chain reaction was used to detect mRNA expression of miR-137 and SDS22. A dual-luciferase reporter assay was employed to verify the direct interaction between miR-137 and SDS22. The internal morphology of cells and cell apoptosis was assessed by TUNEL staining observed under a transmission electron microscope. Meanwhile, the protein expression of oxidative stress-related, apoptosis-related, and activated c-Jun N-terminal kinase (JNK)/activator protein-1 (AP-1) signaling-related genes were analyzed by western blotting. Low strength shear stress (0-5 dyn/cm2) caused a negative change of HAEC surface and internal morphology in an intensity-dependent manner, and these changes were gradually weakened when shear stress was increased more than 5 dyn/cm2. Furthermore, low-intensity shear stress promoted oxidative stress response, accelerated cell apoptosis, and upregulated miR-137 expression and JNK/AP-1 signaling in HAECs. MiR-137 directly targets SDS22. Knockdown of miR-137 noticeably reduced activation of JNK/AP-1 signaling, oxidative stress response, and cell apoptosis induced by shear stress. MiR-137 regulated low-intensity shear stress-induced human aortic endothelial cell ER stress and cell apoptosis via JNK/AP-1 signaling.

A novel R3 MYB transcriptional repressor, MaMYBx, finely regulates anthocyanin biosynthesis in grape hyacinth.

R3-MYBs negatively regulate anthocyanin pigmentation in plants. However, how R3-MYB repressors finely modulate anthocyanin biosynthesis in cooperation with R2R3-MYB activators remains unclear in monocots. We previously identified two anthocyanin-related R2R3-MYB activators (MaMybA and MaAN2) in grape hyacinth (Muscari spp.). Here, we isolated a R3-MYB repressor, MaMYBx, and characterized its role in anthocyanin biosynthesis using genetic and biochemical markers. The temporal expression pattern of MaMYBx was similar to that of MaMybA and MaAN2, and it was correlated with anthocyanin accumulation during flower development. MaMYBx could be activated either by MaMybA alone or by MaMybA/MaAN2 and cofactor MabHLH1, and it suppressed its own activation and that of MaMybA promoters mediated by MaMybA/MaAN2 and MabHLH1. Like MaMybA, MaMYBx interacted with MabHLH1. MaDFR and MaANS transcription and anthocyanin accumulation mediated by MaMybA/MaAN2 and MabHLH1 were inhibited by MaMYBx. Overexpression of MaMYBx in tobacco greatly reduced flower pigmentation and repressed the expression of late structural and regulatory anthocyanin pathway genes. Thus, MaMYBx finely regulates anthocyanin biosynthesis by binding to MabHLH1 and disrupting the R2R3 MYB-bHLH complex in grape hyacinth. The regulatory network of transcriptional activators and repressors modulating anthocyanin biosynthesis is conserved within monocots. MaMYBx seems a potentially valuable target for flower color modification in ornamental plants.

Antiatherosclerotic Activity of Eriocitrin in High-Fat-Diet-Induced Atherosclerosis Model Rats.

Atherosclerosis is a multifactorial disease that develops and progresses in the arterial wall in response to a variety of stimuli. Among various other stimuli, hyperlipidemia is an extremely important factor that is correlated with the development of atherosclerosis. Lemon and citrus fruits contain various bioactive flavonoids, such as eriocitrin, that prevent obesity and related metabolic diseases. Therefore we concentrated on eriocitrin, a potent flavonoid with numerous therapeutic properties, particularly its beneficial lipid-lowering action in rats subjected to high fat diet. The anti-atherosclerotic efficacy of eriocitrin was assessed in rats administered a diet rich in fat. Wistar rats were divided into five groups consisting of six animals in all groups. Group I served the control, Group II was fed a high-fat diet (HFD), and the third and fourth groups were fed an HFD supplemented with varying doses of eriocitrin, and the last group was administered simvastatin for the last 30 days. Body weight, organ weight, lipid and lipoprotein parameters, cardiac and inflammatory markers, and histological examination were evaluated in animals induced with an HFD. Eriocitrin displayed a significant anti-atherosclerotic action by lowering the body weight, organ weight, reduction in lipid content, cardiac and inflammatory markers, myocardial changes confirmed by histopathology, malondialdehyde and increased antioxidant enzyme activities, nitric oxide, as well as 6-keto-PGF1α and high-density lipoprotein levels in rats fed an HFD. The findings of the experiment suggest that the anti-atherosclerotic action of eriocitrin was due to its modulatory activity in lipid metabolism. Considering the overall results of the study it can be validated that a use of flavonoid eriocitrin might be beneficial in altering HFD-induced alterations in atherosclerotic rats.

A novel R2R3-MYB from grape hyacinth, MaMybA, which is different from MaAN2, confers intense and magenta anthocyanin pigmentation in tobacco.

BACKGROUND: The primary pigments in flowers are anthocyanins, the biosynthesis of which is mainly regulated by R2R3-MYBs. Muscari armeniacum is an ornamental garden plant with deep cobalt blue flowers containing delphinidin-based anthocyanins. An anthocyanin-related R2R3-MYB MaAN2 has previously been identified in M. armeniacum flowers; here, we also characterized a novel R2R3-MYB MaMybA, to determine its function and highlight similarities and differences between MaMybA and MaAN2. RESULTS: In this study, a novel anthocyanin-related R2R3-MYB gene was isolated from M. armeniacum flowers and functionally identified. A sequence alignment showed that MaMybA contained motifs typically conserved with MaAN2 and its orthologs. However, the shared identity of the entire amino acid sequence between MaMybA and MaAN2 was 43.5%. Phylogenetic analysis showed that they were both clustered into the AN2 subgroup of the R2R3-MYB family, but not in the same branch. We also identified a IIIf bHLH protein, MabHLH1, in M. armeniacum flowers. A bimolecular fluorescence complementation assay showed that MabHLH1 interacted with MaMybA or MaAN2 in vivo; a dual luciferase assay indicated that MaMybA alone or in interaction with MabHLH1 could regulate the expression of MaDFR and AtDFR, but MaAN2 required MabHLH1 to do so. When overexpressing MaMybA in Nicotiana tabacum 'NC89', the leaves, petals, anthers, and calyx of transgenic tobacco showed intense and magenta anthocyanin pigments, whereas those of OE-MaAN2 plants had lighter pigmentation. However, the ovary wall and seed skin of OE-MaMybA tobacco were barely pigmented, while those of OE-MaAN2 tobacco were reddish-purple. Moreover, overexpressing MaMybA in tobacco obviously improved anthocyanin pigmentation, compared to the OE-MaAN2 and control plants, by largely upregulating anthocyanin biosynthetic and endogenous bHLH genes. Notably, the increased transcription of NtF3'5'H in OE-MaMybA tobacco might lead to additional accumulation of delphinidin 3-rutinoside, which was barely detected in OE-MaAN2 and control plants. We concluded that the high concentration of anthocyanin and the newly produced Dp3R caused the darker color of OE-MaMybA compared to OE-MaAN2 tobacco. CONCLUSION: The newly identified R2R3-MYB transcription factor MaMybA functions in anthocyanin biosynthesis, but has some differences from MaAN2; MaMybA could also be useful in modifying flower color in ornamental plants.

Identification and Functional Analysis of a Flavonol Synthase Gene from Grape Hyacinth.

Flavonols are important copigments that affect flower petal coloration. Flavonol synthase (FLS) catalyzes the conversion of dihydroflavonols to flavonols. In this study, we identified a FLS gene, MaFLS, expressed in petals of the ornamental monocot Muscari aucheri (grape hyacinth) and analyzed its spatial and temporal expression patterns. qRT-PCR analysis showed that MaFLS was predominantly expressed in the early stages of flower development. We next analyzed the in planta functions of MaFLS. Heterologous expression of MaFLS in Nicotiana tabacum (tobacco) resulted in a reduction in pigmentation in the petals, substantially inhibiting the expression of endogenous tobacco genes involved in anthocyanin biosynthesis (i.e., NtDFR, NtANS, and NtAN2) and upregulating the expression of NtFLS. The total anthocyanin content in the petals of the transformed tobacco plants was dramatically reduced, whereas the total flavonol content was increased. Our study suggests that MaFLS plays a key role in flavonol biosynthesis and flower coloration in grape hyacinth. Moreover, MaFLS may represent a new potential gene for molecular breeding of flower color modification and provide a basis for analyzing the effects of copigmentation on flower coloration in grape hyacinth.

MiR-214 sensitizes human colon cancer cells to 5-FU by targeting Hsp27.

Overcoming chemorestistance to 5-fluorouracil (5-FU) could offer a new treatment option for highly malignant colon cancer. In our study, differential microRNA expression profiling revealed that miR-214 is downregulated in 5-FU-resistant colon cancer cells compared to normal cells. In vitro, miR-214 could sensitize non-resistant colon cancer cells and 5-FU-resistant colon cancer cellsto 5-FU. Functionally, miR-214 inhibited cell clone formation and cell growth and enhanced 5-FU-inducing cell apoptosis and caspase-3 levels. MiR-214 targeted heat shock protein 27 (Hsp27), as confirmed via dual luciferase reporter assays and western blots. Hsp27 also sensitized HT-29 and LoVo to 5-FU by enhancing cell apoptosis. Overexpression of Hsp27 could block miR-214 with an effect on the sensitivity of colon cancer cells to 5-FU. In conclusion, miR-214 sensitizes colon cancer cells to 5-FU by targeting Hsp27, indicating a significant role for this miRNA in colon cancer chemotherapy.

Laminar shear stress alters endothelial KCa2.3 expression in H9c2 cells partially via regulating the PI3K/Akt/p300 axis.

In cardiac tissues, myoblast atrial myocytes continue to be exposed to mechanical forces including shear stress. However, little is known about the effects of shear stress on atrial myocytes, particularly on ion channel function, in association with disease. The present study demonstrated that the Ca2+­activated K+ channel (KCa)2.3 serves a vital role in regulating arterial tone. As increased intracellular Ca2+ levels and activation of histone acetyltransferase p300 (p300) are early responses to laminar shear stress (LSS) that result in the transcriptional activation of genes, the role of p300 and the phosphoinositide3­kinase (PI3K)/protein kinase B (Akt) pathway, an intracellular pathway that promotes the growth and proliferation rather than the differentiation of adult cells, in the LSS­dependent regulation of KCa2.3 in cardiac myoblasts was examined. In cultured H9c2 cells, exposure to LSS (15 dyn/cm2) for 12 h markedly increased KCa2.3 mRNA expression. Inhibiting PI3K attenuated the LSS­induced increases in the expression and channel activity of KCa2.3, and decreased the phosphorylation levels of p300. The upregulation of these channels was abolished by the inhibition of Akt through decreasing p300 phosphorylation. ChIP assays indicated that p300 was recruited to the promoter region of the KCa2.3 gene. Therefore, the PI3K/Akt/p300 axis serves a crucial role in the LSS­dependent induction of KCa2.3 expression, by regulating cardiac myoblast function and adaptation to hemodynamic changes. The key novel insights gained from the present study are: i) KCa2.3 was upregulated in patients with atrial fibrillation (AF) and in patients with AF combined with mitral value disease; ii) LSS induced a profound upregulation of KCa2.3 mRNA and protein expression in H9c2 cells; iii) PI3K activation was associated with LSS­induced upregulation of the KCa2.3 channel; iv) PI3K activation was mediated by PI3K/Akt­dependent Akt activation; and v) LSS induction of KCa2.3 involved the binding of p300 to transcription factors in the promoter region of the KCa2.3 gene.

Effect of silencing lncRNATUG1 on rapamycin-induced inhibition of endothelial cell proliferation and migration.

Angiogenesis refers to the formation of new blood vessels from existing blood vessels. The proliferation and migration of endothelial cells serves a key function in this process. Previous research has demonstrated that rapamycin suppresses endothelial cell proliferation and migration, as well as angiogenesis. However, the mechanism by which rapamycin inhibits the proliferation and migration of endothelial cells remains unclear. Long noncoding RNAs (lncRNAs) serve a key function in the regulation of endothelial cell function. The aim of the current study was to investigate whether lncRNA taurine upregulated 1 (lncRNATUG1) is involved in rapamycin-induced inhibition of proliferation and migration in human umbilical vein endothelial cells (HUVECs). Reverse transcription quantitative polymerase chain reaction results indicated that the expression of lncRNATUG1 was upregulated in HUVECs that had been cultured with rapamycin. Subsequently, HUVECs were transfected with siRNAs and CCK-8 assays were performed to detect cell proliferation; additionally, flow cytometry was employed to detect cell apoptosis, and wound healing assays were performed to investigate cell migration. The results demonstrated that rapamycin suppressed the proliferation and migration of HUVECs, and promoted the apoptosis of HUVECs. In addition, rapamycin downregulated the expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-2 and MMP-9 in HUVECs. However, silencing of lncRNATUG1 was revealed to attenuate rapamycin-induced inhibition of cellular proliferation and migration of HUVECs, as well as upregulating the expression of VEGF, MMP2 and MMP-9. These results suggested that lncRNATUG1 regulates rapamycin-induced inhibition of endothelial cell proliferation and migration. Therefore, lncRNATUG1 may serve a key function in rapamycin-induced inhibition of endothelial cell proliferation and migration.

Exosomes from microRNA-199-3p-modified adipose-derived stem cells promote proliferation and migration of endothelial tip cells by downregulation of semaphorin 3A.

Exosomes secreted by adipose-derived stem cells (ADSCs) have been shown to promote angiogenesis. This study aimed to investigate the effect of exosomes from ADSCs (ADSCs-Exos) on proliferation and migration of endothelial tip cells. In this study, ADSCs were analyzed by flow cytometry. The protein levels were examined by western blot. Cell proliferation and migration were assessed by CCK-8 assay, EdU cell proliferation assay and transwell migration assay. A luciferase reporter assay was performed to confirm whether sema3A was a direct target of miR-199a/b-3p. The results showed that ADSCs-Exos strikingly promoted the proliferation and migration of endothelial tip cells. The expression levels of miR-199a-3p and miR-199b-3p were strikingly increased in ADSCs and ADSCs-Exos. Compared to the Exosscramble group, the proliferation and migration of endothelial tip cells was dramatically increased in the Exos199 mimic group, but remarkably decreased in the Exos199 inhibitor group. Moreover, Sema3A was a target of miR-199-3p. The stimulatory effects of Exos199 mimic on the proliferation and migration of endothelial tip cells were negated by Sema3A overexpression. Besides, the expression of tissue inhibitor of metalloproteinase 3 (TIMP3) was decreased, and the expression of matrix metalloproteinases 9 (MMP9) and proliferating cell nuclear antigen (PCNA) were increased in endothelial tip cells co-cultured with ADSCs-Exos, which were substantially enhanced by Exos199 mimic treatment. However, the effect of Exos199 mimic on the protein expression of TIMP3, MMP9 and PCNA were negated by upregulation of Sema3A. In conclusion, exosomes from miR-199-3p-modified ADSCs promote proliferation and migration of endothelial tip cells by downregulation of sema3A.

Alginate oligosaccharide indirectly affects toll-like receptor signaling via the inhibition of microRNA-29b in aneurysm patients after endovascular aortic repair.

Endovascular aortic repair (EVAR) is often followed by aneurysm recurrence. Alginate oligosaccharide (AOS) has potential antitumor properties as a natural product while the related mechanisms remain unclear. Toll-like receptor (TLR) signaling is associated with inflammatory activity of aneurysm and may be affected by miR-29b. Thus, inhibitory function of AOS on aneurysms was explored by measuring the important molecules in TLR4 signaling. After EVAR, a total of 248 aortic aneurysm patients were recruited and randomly assigned into two groups: AOS group (AG, oral administration 10-mg AOS daily) and control group (CG, placebo daily). The size of residual aneurysms, aneurysm recurrence, and side effects were investigated. Aneurysm recurrence was determined by Kaplan-Meier analysis. After 2 years, eight and two patients died in the CG and AG, respectively. The sizes of residual aneurysms were significantly larger in the CG than in the AG (P<0.05). The incidence of aneurysm recurrence was also significantly higher in the CG than in the AG (P<0.05). AOS treatment reduced the levels of miR-29b, TLR4, mitogen-activated protein kinase (MAPK), nuclear factor kappa B (NF-kappa B), interleukin 1 (IL-1) beta, and interleukin 6 (IL-6). Overexpression and silence of miR-29b increased and reduced the level of TLR4, phospho-p65 NF-kappa B, phospho-p38 MAPK, IL-1 beta, and IL-6. Spearman's rank correlation analysis shows that the level of miR-29b is positively related to the levels of TLR4, NF-kappa B, IL-1 beta, and IL-6 (P<0.05). Thus, AOS represses aneurysm recurrence by indirectly affecting TLR signaling via miR-29b.

Slit2 suppresses endothelial cell proliferation and migration by inhibiting the VEGF-Notch signaling pathway.

Slit homolog 2 (Slit2) is distributed in various tissues and participates in numerous cellular processes; however, the role of Slit2 in the regulation of angiogenesis remains controversial, since it has previously been reported to exert proangiogenic and antiangiogenic activities. The present study aimed to investigate the effects of Slit2 on vascular endothelial cell proliferation and migration in vitro, and to reveal the possible underlying signaling pathway. Aortic endothelial cells were isolated from Sprague Dawley rats and cultured. Cell proliferation assay, cell migration assay, immunocytochemistry and small interfering RNA transfection were subsequently performed. The results demonstrated that exogenous Slit2 administration markedly suppressed TNF­α­induced endothelial cell proliferation and migration in vitro. In addition, TNF­α application upregulated the protein expression levels of vascular endothelial growth factor (VEGF) and Notch in RAECs, whereas Slit2 administration downregulated VEGF and Notch expression in RAECs cultured in TNF­α conditioned medium. Further studies indicated that knockdown of VEGF suppressed the effects of TNF­α on the induction of RAEC proliferation and migration. VEGF knockdown­induced inhibition of RAEC proliferation and migration in TNF­α conditioned medium was also achieved without Slit2 administration. Furthermore, VEGF knockdown markedly decreased Notch1 and Notch2 expression. These results indicated that Slit2 suppresses TNF­α­induced vascular endothelial cell proliferation and migration in vitro by inhibiting the VEGF­Notch signaling pathway. Therefore, Slit2 may inhibit the proliferation and migration of endothelial cells during vascular development.

Iodine-125 irradiation inhibits invasion of gastric cancer cells by reactivating microRNA-181c expression.

Iodine-125 (125I) seed implantation has been widely used for the treatment of unresectable advanced tumors. However, the molecular mechanisms underlying the tumor-suppressive effects of 125I irradiation have not been fully elucidated. The present study demonstrated that 125I irradiation suppresses cell viability and inhibits cell invasiveness of gastric cancer KATO-III and MKN45 cells. Further mechanistic analysis suggested the involvement of microRNA (miR)-181c in the inhibitory effects induced by 125I irradiation. Methylated DNA immunoprecipitation coupled with quantitative-polymerase chain reaction demonstrated that treatment with 125I irradiation, at the dose of 4 Gy, induced promoter demethylation of the miR-181c gene in KATO-III and MKN45 cells. Following irradiation, the expression of miR-181c was significantly increased, which may be attributed to the demethylation caused by 125I irradiation. In addition, upregulation of miR-181c by administration of miR-181c mimics decreased cell invasion, suggesting the role of miR-181c as a tumor suppressor. More importantly, the tumor-suppressive effects of 125I irradiation were significantly compromised by the introduction of miR-181c inhibitors. Overall, these results reveal that 125I irradiation inhibits invasiveness of gastric cancer cells by reactivating miR-181c at the epigenetic level, thereby providing important molecular evidence for the anticancer effects of 125I irradiation.

Iodine-125 induces apoptosis via regulating p53, microvessel density, and vascular endothelial growth factor in colorectal cancer.

BACKGROUND: Iodine interstitial brachytherapy has been widely reported for treating colorectal cancer (CRC). However, the inhibitory molecular mechanism of iodine-125 (I-125) on CRC has not been reported. METHODS: To illustrate the inhibitory mechanism of iodine-125 (I-125) on CRC, we established the animal models of CRC via the injection of HCT-8 cells into nude mice. Subsequently, the I-125 granules were implanted into the tumor of the animal model at different dosages. Proliferating cell nuclear antigen and terminal transferase dUTP nick end labeling were used to detect the apoptosis of the tumor cells. Immunohistochemistry SP staining was used to measure the expression of p53 protein. The protein levels were examined with western blot and ELISA. Meanwhile, microvessel density (MVD) was counted by endothelial cells immunostained by anti-CD34 antibody. RESULTS: The results showed that I-125 protests against CRC via increasing the protein level of p53 and decreasing the level of vascular endothelial growth factor (VEGF), leading to the decrease of MVD in CRC (P <0.0001). An effective inhibition dosage of I-125 ranged from 0.4 to 0.8 mCi. CONCLUSIONS: The inhibitory mechanisms of iodine on CRC acted through an increase in the level of p53 and a decrease in the level of VEGF, resulting in a decrease of MVD.