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 nov...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.展开更多
Background: Long noncoding RNAs (lncRNAs) play pivotal roles in various malignant tumors. Epidermal growth factor receptor (EGFR) signaling is associated with the pathogenesis of cutaneous squamous cell carcinoma (cSC...Background: Long noncoding RNAs (lncRNAs) play pivotal roles in various malignant tumors. Epidermal growth factor receptor (EGFR) signaling is associated with the pathogenesis of cutaneous squamous cell carcinoma (cSCC). This study aimed to explore the role of LINC00520 in the development of cSCC via EGFR and phosphoinositide 3-kinase-protein kinase B (PI3K/Akt) signaling pathways. Methods: A microarray analysis was applied to screen differentially expressed lncRNAs in cSCC samples. The A431 cSCC cell line was transfected and assigned different groups. The expression patterns of LINC00520, EGFR, and intermediates in the PI3K/Akt pathway were characterized using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting analysis. Cell proliferation, migration, and invasion were detected using the MTT assay, scratch test, and Transwell assay, respectively. Cell-based experiments and a tumorigenicity assay were conducted to assess the effect of LINC00520 on cSCC progression. This study was ended in September 2017. Comparisons between two groups were analyzed with t-test and comparisons among multiple groups were analyzed using one-way analysis of variance. The nonparametric Wilcoxon rank sum test was used to analyze skewed data. The enumerated data were analyzed using the chi-square test or Fisher exact test. Results: Data from chip GSE66359 revealed depletion of LINC00520 in cSCC. Cells transfected with LINC00520 vector and LINC00520 vector + si-EGFR showed elevated LINC00520 level but decreased levels of the EGFR, PI3K, AKT, VEGF, MMP-2 and MMP-9 mRNAs and proteins, and inhibition of the growth, migration and adhesion of cSCC cells, while the si-LINC00520 group showed opposite trends (all P < 0.05). Compared with the LINC00520 vector group, the LINC00520 vector + si-EGFR group showed decreased levels of the EGFR, PI3K, AKT, VEGF, MMP-2 and MMP-9 mRNAs and proteins, and inhibition of the growth, migration and adhesion of cSCC cells, while the LINC00520 vector+ EGFR vector group showed opposite results (all P < 0.05). Conclusion: Based on our results, LINC00520-targeted EGFR inhibition might result in the inactivation of the PI3K/Akt pathway, thus inhibiting cSCC development.展开更多
In vitro studies have shown that estrogen receptor β can attenuate the cytotoxic effect of amyloid protein on PC12 cells through the Akt pathway without estrogen stimulation. In this study, we aimed to observe the ef...In vitro studies have shown that estrogen receptor β can attenuate the cytotoxic effect of amyloid protein on PC12 cells through the Akt pathway without estrogen stimulation. In this study, we aimed to observe the effect of estrogen receptor β in Alzheimer＇s disease rat models established by intraventricular injection of amyloid β protein. Estrogen receptor β lentiviral particles delivered via intraventricular injection increased Akt content in the hippocampus, decreased interleukin-1β mRNA tumor necrosis factor a mRNA and amyloid β protein levels in the hippocampus, and improved the learning and memory capacities in AIzheimer＇s disease rats. Estrogen receptor β short hairpin RNA lentiviral particles delivered via intraventricular injection had none of the above impacts on AIzheimer＇s disease rats. These experimental findings indicate that estrogen receptor β, independent from estrogen, can reduce inflammatory reactions and amyloid β deposition in the hJppocampus of AIzheimer＇s disease rats, and improve learning and memory capacities. This effect may be mediated through activation of the Akt pathway.展开更多
Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and af...Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin（m TOR） is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1（m TORC1） and m TOR Complex 2（m TORC2） and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase（PI 3-K）,protein kinase B（Akt）,AMP activated protein kinase（AMPK）,silent mating type information regulation 2 homolog 1（Saccharomyces cerevisiae）（SIRT1）,Wnt1 inducible signaling pathway protein 1（WISP1）,and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.展开更多
AIM： To investigate the effcacy of fu-qi granule （FQG） on carbon tetrachloride （CCl4） induced liver fbrosis in rats and the underlying mechanisms. METHODS： Sixty rats were randomly divided into six groups： norm...AIM： To investigate the effcacy of fu-qi granule （FQG） on carbon tetrachloride （CCl4） induced liver fbrosis in rats and the underlying mechanisms. METHODS： Sixty rats were randomly divided into six groups： normal control group, CCl4 induced liver fbrosis group, AnluoHuaxianWan group and three treatment groups of FQG. Treatment of rats with intraperitoneal injection of carbon tetrachloride solution at 0.3 mL per 100 g body weigh twice a week for 8 wk. The normal control group the rats were given the media （olive oil） at the same time. In the frst 2 wk, rats were raised with feedstuff （80% corn meal, 20% lard, 0.5% cholesterol）. Serum samples were collected for alanine transaminase, aspartate aminotransferase, alkaline phosphatase, albumin, total protein assay and typical histopathological changes was observed in Hematoxylin-eosin staining sections. Smooth muscle alpha actin （α-SMA） was analyzed with immunohistochemistry. Mammalian target of rapamycin （mTOR） and hypoxia-inducible factor-1 （HIF-1α） expressions were detected by Western blot-ting. Tissue inhibitor of matrix metalloproteinases-1 （TIMP-1） and matrix metalloproteinases-9 （MMP-9） were measured with semi-quantitative reverse transcriptase-polymerase chain reaction.RESULTS： FQG significantly reduced the serum levels of alanine transaminase, aspartate aminotransferase, alkaline phosphatase and increased the serum contents of albumin, total protein in rats with liver fibrosis. Moreover, FQG promoted extracellular matrix degradation by increasing MMP-9 and inhibiting TIMP-1 and α-SMA. mTOR and HIF-1α expression in liver significantly decreased in the rats treated with FQG. CONCLUSION： The results indicated that FQG signi-fcantly reverse fbrosis induced by CCl4, which should be developed as a new and promising preparation for the prevention of liver fbrosis.展开更多
Proliferation suppression and apoptosis are the prominent characteristics induced by heat stress（HS） in cells, whereas the effects of HS on cell growth（mass accumulation） are unknown. In this study, Lantang swine...Proliferation suppression and apoptosis are the prominent characteristics induced by heat stress（HS） in cells, whereas the effects of HS on cell growth（mass accumulation） are unknown. In this study, Lantang swine（an indigenous breed of China） skeletal muscle satellite cells（SCs） were pre-cultured at 37 °C for 24 h. The HS group was subjected to HS at 41 °C, while the control group was maintained at 37 °C. Heat shock protein 70（HSP70） expression and SC size are significantly increased（P〈0.05） by HS, but cell proliferation is suppressed（P〈0.05） and apoptosis is induced（P〈0.05）. HS led to a lower percentage of SCs in the G0/G1 phase（P〈0.05） together with a higher percentage of SCs in the S phase（P〈0.05）. However, the percentage of SCs in the G2/M phase was decreased（P〈0.05） at 48 h but then increased（P〈0.05） at 72 h with HS. In addition, the phosphorylation ratios of protein kinase b（Akt）, ribosomal protein S6 kinase（S6K）, and ribosomal protein S6 were increased（P〈0.05） by HS. Nevertheless, the phosphorylation ratios of the 4E binding protein 1 and the eukaryotic initiation factor-4E were indistinguishable（P〉0.05） from those of the control group. The phosphorylation ratio of the mammalian target of rapamycin（m TOR）（Ser^2448） increased（P〈0.05） within 48 h, and apparent differences were abrogated at 72 h（P〉0.05）. Moreover, cleaved caspase-3 expression was increased at 72 h（P〈0.05）. These findings indicate that HS induces apoptosis and disrupts cell cycle distribution to decrease the number of cells. Additionally, HS can promote SC growth via an activated Akt/m TOR/S6 K signaling pathway.展开更多
基金supported by grants from the National Natural Science Foundation (31872979, 31572366)the National Key Research and Development Program of China (2017YFD0502002)the National Basic Research Programs of China (2015CB943102)。
文摘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.
文摘Background: Long noncoding RNAs (lncRNAs) play pivotal roles in various malignant tumors. Epidermal growth factor receptor (EGFR) signaling is associated with the pathogenesis of cutaneous squamous cell carcinoma (cSCC). This study aimed to explore the role of LINC00520 in the development of cSCC via EGFR and phosphoinositide 3-kinase-protein kinase B (PI3K/Akt) signaling pathways. Methods: A microarray analysis was applied to screen differentially expressed lncRNAs in cSCC samples. The A431 cSCC cell line was transfected and assigned different groups. The expression patterns of LINC00520, EGFR, and intermediates in the PI3K/Akt pathway were characterized using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting analysis. Cell proliferation, migration, and invasion were detected using the MTT assay, scratch test, and Transwell assay, respectively. Cell-based experiments and a tumorigenicity assay were conducted to assess the effect of LINC00520 on cSCC progression. This study was ended in September 2017. Comparisons between two groups were analyzed with t-test and comparisons among multiple groups were analyzed using one-way analysis of variance. The nonparametric Wilcoxon rank sum test was used to analyze skewed data. The enumerated data were analyzed using the chi-square test or Fisher exact test. Results: Data from chip GSE66359 revealed depletion of LINC00520 in cSCC. Cells transfected with LINC00520 vector and LINC00520 vector + si-EGFR showed elevated LINC00520 level but decreased levels of the EGFR, PI3K, AKT, VEGF, MMP-2 and MMP-9 mRNAs and proteins, and inhibition of the growth, migration and adhesion of cSCC cells, while the si-LINC00520 group showed opposite trends (all P < 0.05). Compared with the LINC00520 vector group, the LINC00520 vector + si-EGFR group showed decreased levels of the EGFR, PI3K, AKT, VEGF, MMP-2 and MMP-9 mRNAs and proteins, and inhibition of the growth, migration and adhesion of cSCC cells, while the LINC00520 vector+ EGFR vector group showed opposite results (all P < 0.05). Conclusion: Based on our results, LINC00520-targeted EGFR inhibition might result in the inactivation of the PI3K/Akt pathway, thus inhibiting cSCC development.
文摘In vitro studies have shown that estrogen receptor β can attenuate the cytotoxic effect of amyloid protein on PC12 cells through the Akt pathway without estrogen stimulation. In this study, we aimed to observe the effect of estrogen receptor β in Alzheimer＇s disease rat models established by intraventricular injection of amyloid β protein. Estrogen receptor β lentiviral particles delivered via intraventricular injection increased Akt content in the hippocampus, decreased interleukin-1β mRNA tumor necrosis factor a mRNA and amyloid β protein levels in the hippocampus, and improved the learning and memory capacities in AIzheimer＇s disease rats. Estrogen receptor β short hairpin RNA lentiviral particles delivered via intraventricular injection had none of the above impacts on AIzheimer＇s disease rats. These experimental findings indicate that estrogen receptor β, independent from estrogen, can reduce inflammatory reactions and amyloid β deposition in the hJppocampus of AIzheimer＇s disease rats, and improve learning and memory capacities. This effect may be mediated through activation of the Akt pathway.
基金supported by American Diabetes Association,American Heart Association,NIH NIEHS,NIH NIA,NIH NINDS,and NIH ARRA
文摘Throughout the globe,diabetes mellitus（DM） is increasing in incidence with limited therapies presently available to prevent or resolve the significant complications of this disorder.DM impacts multiple organs and affects all components of the central and peripheral nervous systems that can range from dementia to diabetic neuropathy.The mechanistic target of rapamycin（m TOR） is a promising agent for the development of novel regenerative strategies for the treatment of DM.m TOR and its related signaling pathways impact multiple metabolic parameters that include cellular metabolic homeostasis,insulin resistance,insulin secretion,stem cell proliferation and differentiation,pancreatic β-cell function,and programmed cell death with apoptosis and autophagy.m TOR is central element for the protein complexes m TOR Complex 1（m TORC1） and m TOR Complex 2（m TORC2） and is a critical component for a number of signaling pathways that involve phosphoinositide 3-kinase（PI 3-K）,protein kinase B（Akt）,AMP activated protein kinase（AMPK）,silent mating type information regulation 2 homolog 1（Saccharomyces cerevisiae）（SIRT1）,Wnt1 inducible signaling pathway protein 1（WISP1）,and growth factors.As a result,m TOR represents an exciting target to offer new clinical avenues for the treatment of DM and the complications of this disease.Future studies directed to elucidate the delicate balance m TOR holds over cellular metabolism and the impact of its broad signaling pathways should foster the translation of these targets into effective clinical regimens for DM.
基金Supported by The National Natural Sciences Foundation,No.81173571National Basic Research Program of China,No.2007CB512607The Major Projects of the National Science and Technology,No.2012ZX10005010-002-002
文摘AIM： To investigate the effcacy of fu-qi granule （FQG） on carbon tetrachloride （CCl4） induced liver fbrosis in rats and the underlying mechanisms. METHODS： Sixty rats were randomly divided into six groups： normal control group, CCl4 induced liver fbrosis group, AnluoHuaxianWan group and three treatment groups of FQG. Treatment of rats with intraperitoneal injection of carbon tetrachloride solution at 0.3 mL per 100 g body weigh twice a week for 8 wk. The normal control group the rats were given the media （olive oil） at the same time. In the frst 2 wk, rats were raised with feedstuff （80% corn meal, 20% lard, 0.5% cholesterol）. Serum samples were collected for alanine transaminase, aspartate aminotransferase, alkaline phosphatase, albumin, total protein assay and typical histopathological changes was observed in Hematoxylin-eosin staining sections. Smooth muscle alpha actin （α-SMA） was analyzed with immunohistochemistry. Mammalian target of rapamycin （mTOR） and hypoxia-inducible factor-1 （HIF-1α） expressions were detected by Western blot-ting. Tissue inhibitor of matrix metalloproteinases-1 （TIMP-1） and matrix metalloproteinases-9 （MMP-9） were measured with semi-quantitative reverse transcriptase-polymerase chain reaction.RESULTS： FQG significantly reduced the serum levels of alanine transaminase, aspartate aminotransferase, alkaline phosphatase and increased the serum contents of albumin, total protein in rats with liver fibrosis. Moreover, FQG promoted extracellular matrix degradation by increasing MMP-9 and inhibiting TIMP-1 and α-SMA. mTOR and HIF-1α expression in liver significantly decreased in the rats treated with FQG. CONCLUSION： The results indicated that FQG signi-fcantly reverse fbrosis induced by CCl4, which should be developed as a new and promising preparation for the prevention of liver fbrosis.
基金Project supported by the National 948 Program of China(No.2011-G35)the National Basic Research Program(973)of China(No.2012CB124704)the Science and Technology Planning Project of Guangzhou,Guangdong Province,China(Nos.201510010020 and 201300000035)
文摘Proliferation suppression and apoptosis are the prominent characteristics induced by heat stress（HS） in cells, whereas the effects of HS on cell growth（mass accumulation） are unknown. In this study, Lantang swine（an indigenous breed of China） skeletal muscle satellite cells（SCs） were pre-cultured at 37 °C for 24 h. The HS group was subjected to HS at 41 °C, while the control group was maintained at 37 °C. Heat shock protein 70（HSP70） expression and SC size are significantly increased（P〈0.05） by HS, but cell proliferation is suppressed（P〈0.05） and apoptosis is induced（P〈0.05）. HS led to a lower percentage of SCs in the G0/G1 phase（P〈0.05） together with a higher percentage of SCs in the S phase（P〈0.05）. However, the percentage of SCs in the G2/M phase was decreased（P〈0.05） at 48 h but then increased（P〈0.05） at 72 h with HS. In addition, the phosphorylation ratios of protein kinase b（Akt）, ribosomal protein S6 kinase（S6K）, and ribosomal protein S6 were increased（P〈0.05） by HS. Nevertheless, the phosphorylation ratios of the 4E binding protein 1 and the eukaryotic initiation factor-4E were indistinguishable（P〉0.05） from those of the control group. The phosphorylation ratio of the mammalian target of rapamycin（m TOR）（Ser^2448） increased（P〈0.05） within 48 h, and apparent differences were abrogated at 72 h（P〉0.05）. Moreover, cleaved caspase-3 expression was increased at 72 h（P〈0.05）. These findings indicate that HS induces apoptosis and disrupts cell cycle distribution to decrease the number of cells. Additionally, HS can promote SC growth via an activated Akt/m TOR/S6 K signaling pathway.
