MiR-146a-5p targeting SMAD4 and TRAF6 inhibits adipogenensis through TGF-β and AKT/mTORC1 signal pathways in porcine intramuscular preadipocytes

Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.

Elevated retinol binding protein 4 levels are associated with atherosclerosis in diabetic rats via JAK2/STAT3 signaling pathway

BACKGROUND Atherosclerosis is a major cause of mortality worldwide and is driven by multiple risk factors,including diabetes,which results in an increased atherosclerotic burden,but the precise mechanisms for the occurrence and development of diabetic atheroscerosis have not been fully elucidated.AIM To summarize the potential role of retinol binding protein 4(RBP4) in the pathogenesis of diabetic atheroscerosis,particularly in relation to the RBP4-Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)signaling pathway.METHODS Male Wistar rats were randomly divided into three groups,including a control group(NC group),diabetic rat group(DM group),and diabetic atherosclerotic rat group(DA group).The contents of total cholesterol(TC), high-density lipoprotein cholesterol(HDL-c), triglycerides(TG), low-density lipoprotein cholesterol(LDLc), fasting insulin(FINS),fasting plasma glucose,and hemoglobin A1 c(HbA1 c)were measured.Moreover,the adipose and serum levels of RBP4,along with the expression levels of JAK2, phosphorylated JAK2(p-JAK2), STAT3,phosphorylated STAT3(p-STAT3), B-cell lymphoma-2(Bcl-2), and Cyclin D1 in aortic tissues were also measured.Besides,homeostasis model assessment of insulin resistance(HOMA-IR) and atherogenic indexes(AI) were calculated.RESULTS Compared with the NC and DM groups,the levels LDL-c,TG,TC,FINS,HOMAIR,RBP4,and AI were upregulated,whereas that of HDL-c was downregulated in the DA group(P <0.05);the mRNA levels of JAK2,STAT3,Cyclin D1,and Bcl-2 in the DA group were significantly increased compared with the NC group and the DM group;P-JAK2,p-JAK2/JAK2 ratio,p-STAT3,p-STAT3/STAT3 ratio,Cyclin D1,and Bcl-2 at protein levels were significantly upregulated in the DA group compared with the NC group and DM group.In addition,as shown by Pearson analysis,serum RBP4 had a positive correlation with TG,TC,LDL-c,FINS,HbA1 C,p-JAK2,p-STAT3,Bcl-2,Cyclin D1,AI,and HOMA-IR but a negative correlation with HDL-c.In addition,multivariable logistic regression analysis showed that serum RBP4,p-JAK2,p-STAT3,and LDL-c were predictors of the presence of diabetic atherosclerosis.CONCLUSION RBP4 could be involved in the initiation or progression of diabetic atherosclerosis by regulating the JAK2/STAT3 signaling pathway.

Ramulus Cinnamomi extract attenuates neuroinflammatory responses via downregulating TLR4/MyD88 signaling pathway in BV2 cells

Ramulus Cinnamomi （RC）, a traditional Chinese herb, has been used to attenuate inflammatory responses. The purpose of this study was to investigate the effect of RC extract on lipopolysaccharide （LPS）-induced neuroinflammation in BV2 microglial cells and the underlying mechanisms involved. BV2 cells were incubated with normal medium （control group）, LPS, LPS plus 30 pg/mL RC extract, or LPS plus 100 pg/mL RC extract. The BV2 cell morphology was observed under an optical microscope and cell viability was detected by MTT assay. Nitric oxide level in BV2 cells was detected using Griess regents, and the levels of interleukin-6, interleukin-1 β, and tumor necrosis factor u in BV2 cells were determined by ELISA. The expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 proteins were detected by western blot assay. Compared with the LPS group, both 30 and 100 μg/mL RC extract had no significant effect on the viability of BV2 cells. The levels of nitric oxide, interleukin-6, interleukin-1β and tumor necrosis factor ct in BV2 cells were all significantly increased after LPS induction, and the levels were significantly reversed after treatment with 30 and 100 μg/mL RC extract. Furthermore, RC extract significantly inhibited the protein expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 in LPS-induced BV2 cells. Our findings suggest that RC extract alleviates neuroinflammation by downregulating the TLR4/MyD88 signaling pathway.

Correlation between receptor-interacting protein 140 expression and directed differentiation of human embryonic stem cells into neural stem cells

Overexpression of receptor-interacting protein 140（RIP140） promotes neuronal differentiation of N2 a cells via extracellular regulated kinase 1/2（ERK1/2） signaling.However,involvement of RIP140 in human neural differentiation remains unclear.We found both RIP140 and ERK1/2 expression increased during neural differentiation of H1 human embryonic stem cells.Moreover,RIP140 negatively correlated with stem cell markers Oct4 and Sox2 during early stages of neural differentiation,and positively correlated with the neural stem cell marker Nestin during later stages.Thus,ERK1/2 signaling may provide the molecular mechanism by which RIP140 takes part in neural differentiation to eventually affect the number of neurons produced.

Association of overexpression of TIF1γ with colorectal carcinogenesis and advanced colorectal adenocarcinoma

AIM:To determine the expression and clinical significance of transcriptional intermediary factor 1 gamma (TIF1γ),Smad4 and transforming growth factor-beta (TGFβR) across a spectrum representing colorectal cancer (CRC) development.METHODS:Tissue microarrays were prepared from archival paraffin embedded tissue,including 51 colorectal carcinomas,25 tubular adenomas (TA) and 26 HPs,each with matched normal colonic epithelium.Immunohistochemistry was performed using antibodies against TIF1γ,Smad4 and TGFβ RⅡ.The levels of expression were scored semi-quantitatively (score 0-3 or loss and retention for Smad4).RESULTS:Overexpression of TIF1γ was detected in 5/26 (19%) HP;however,it was seen in a significantly higher proportion of neoplasms,15/25 (60%) TAs and 24/51 (47%) CRCs (P<0.05).Normal colonic mucosa,HP,and TAs showed strong Smad4 expression,while its expression was absent in 22/51 (43%) CRCs.Over-expression of TGFβ RⅡ was more commonly seen in neoplasms,13/25 (52%) TAs and 29/51 (57%) CRCs compared to 9/26 (35%) HP (P<0.05).Furthermore,there was a correlation between TIF1γ overexpression and Smad4 loss in CRC (Kendall tau rank correlation value=0.35,P<0.05).The levels of TIF1γ overexpression were significantly higher in stage Ⅲ than in stage Ⅰ and Ⅱ CRC (P<0.05).CONCLUSION:The findings suggest that over-expression of TIF1γ occurs in early stages of colorectal carcinogenesis,is inversely related with Smad4 loss,and may be a prognostic indicator for poor outcome.

Emerging interleukin-1 receptor-associated kinase 4(IRAK4)inhibitors or degraders as therapeutic agents for autoimmune diseases and cancer

Interleukin-1 receptor-related kinase(IRAK4)is a widely expressed serine/threonine kinase involved in the regulation of innate immunity.IRAK4 plays a pivotal role as a key kinase within the downstream signaling pathway cascades of interleukin-1 receptors(IL-1R)and Toll-like receptors(TLRs).The signaling pathways orchestrated by IRAK4 are integral to inflammatory responses,and its overexpression is implicated in the pathogenesis of inflammatory diseases,autoimmune disorders,and cancer.Consequently,targeting IRAK4-mediated signaling pathways has emerged as a promising therapeutic strategy.Small molecule inhibitors and degraders designed to modulate IRAK4 have shown efficacy in mitigating related diseases.In this paper,we will provide a detailed description of the structure and function of IRAK4,the role of IRAK4 in related diseases,as well as the currently reported small molecule inhibitors and degraders of IRAK4.It is expected to provide new directions for enriching the clinical treatment of inflammation and related diseases.

Use of network pharmacology and molecular docking to explore the potential mechanism governing the efficacy of Jinhuaqinggan granules in the treatment of novel coronavirus-induced pneumonia

Background:Now that the epidemic of new coronavirus pneumonia(corona virus disease 2019)is spreading all over the world,Jinhuaqinggan granules in the Chinese treatment plan has been proved to be an effective Chinese patent medicine for the treatment of corona virus disease 2019.Methods:This study aims to clarify the possible therapeutic mechanism governing the efficacy of Jinhuaqinggan granules in the treatment of corona virus disease 2019,through using network pharmacology and molecular docking.During the analysis,227 active components were obtained and screened by using the ADME method.Furthermore,282 Jinhuaqinggan granule targets and 56 common targets with corona virus disease 2019 were gathered from various databases.Then the protein-protein interaction network of Jinhuaqinggan granules and corona virus disease 2019 targets were constructed and 6 core targets were selected through network topology analysis.In addition,A total of 262 biological function annotation entries(P<0.01)and 101 pathways(P<0.01)were obtained by gene ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis.Results:Molecular docking showed that quercetin,luteolin,kaempferol,wogonin and naringin had an affinity for SARS-CoV-23CL hydrolase and angiotensin-converting enzyme 2.Conclusion:corona virus disease 2019 can be prevented by the primary targets of Jinhuaqinggan granules.The most important bioactive components in Jinhuaqinggan granules-quercetin,naringenin,luteolin and wogonin-can play antiviral effect,anti-inflammatory storm,regulate immunity by regulating signal transducers and activators of transcription 1,interleukin 4,interferon-γ,heme oxygenase 1 and acting on the lipopolysaccharide response,toll-like receptor signaling pathway,mitogen-activated protein kinase signaling pathway,etc.

Transferrin receptor-targeted immunostimulant for photodynamic immunotherapy against metastatic tumors through β-catenin/CREB interruption

The immunosuppressive phenotype of tumor cells extensively attenuates the immune activation effects of traditional treatments.In this work,a transferrin receptor(TfR)targeted immunostimulant(PTI)is fabricated for photodynamic immunotherapy against metastatic tumors by interrupting β-catenin signal pathway.To synthesize PTI,the photosensitizer conjugated TfR targeting peptide moiety(Palmitic-K(PpIX)-HAIYPRH)is unitized to encapsulate the transcription interrupter of ICG-001.On the one hand,the recognition of PTI and TfR can promote drug delivery into tumor cells to destruct primary tumors through photodynamic therapy and initiate an immunogenic cell death with the release of tumorassociated antigens.On the other hand,PTI will interrupt the binding between b-catenin andcAMP response element-binding protein(CREB),regulating the gene transcription to downregulate programmed death ligand 1(PD-L1)while upregulating CeC motif chemokine ligand 4(CCL4).Furthermore,the elevated CCL4 can recruit the dendritic cells to present tumor-specific antigens and promote T cells activation and infiltration,and the downregulated PD-L1 can avoid the immune evasion of tumor cells and activate systemic anti-tumor immunity to eradicate lung metastasis.This work may inspire the development of antibody antibody-free strategy to activate systemic immune response in consideration of immunosuppressive conditions.

质体反向信号研究进展

细胞内由叶绿体向细胞核发送的信号被称作质体反向信号。它可以协调细胞核与叶绿体编码的基因表达,促进叶绿体发育,并且参与调控植物多种生长发育过程。近年来已经鉴定出一些参与质体反向过程的信号及其转导的组分,为研究质体反向信号的调控网络提供了新视角。本文回顾了质体反向信号的研究历史,并对质体反向信号转导途径及其参与调节生长发育进程等方面的最新进展进行概述。