scholarly journals The concentration of B52, an essential splicing factor and regulator of splice site choice in vitro, is critical for Drosophila development.

1994 ◽  
Vol 14 (8) ◽  
pp. 5360-5370 ◽  
Author(s):  
M E Kraus ◽  
J T Lis
Keyword(s):  
Alternative Splice ◽  
Splice Site ◽  
Developmental Stages ◽  
Immunoblot Analysis ◽  
Splicing Factor ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Alternative Splice Site

B52 is a Drosophila melanogaster protein that plays a role in general and alternative splicing in vitro. It is homologous to the human splicing factor ASF/SF2 which is essential for an early step(s) in spliceosome assembly in vitro and also regulates 5' and 3' alternative splice site choice in a concentration-dependent manner. In vitro, B52 can function as both a general splicing factor and a regulator of 5' alternative splice site choice. Its activity in vivo, however, is largely uncharacterized. In this study, we have further characterized B52 in vivo. Using Western blot (immunoblot) analysis and whole-mount immunofluorescence, we demonstrate that B52 is widely expressed throughout development, although some developmental stages and tissues appear to have higher B52 levels than others do. In particular, B52 accumulates in ovaries, where it is packaged into the developing egg and is localized to nuclei by the late blastoderm stage of embryonic development. We also overexpressed this protein in transgenic flies in a variety of developmental and tissue-specific patterns to examine the effects of altering the concentration of this splicing factor in vivo. We show that, in many cell types, changing the concentration of B52 adversely affects the development of the organism. We discuss the significance of these observations with regard to previous in vitro results.

scholarly journals The concentration of B52, an essential splicing factor and regulator of splice site choice in vitro, is critical for Drosophila development

1994 ◽  
Vol 14 (8) ◽  
pp. 5360-5370
Author(s):  
M E Kraus ◽  
J T Lis
Keyword(s):  
Alternative Splice ◽  
Splice Site ◽  
Developmental Stages ◽  
Immunoblot Analysis ◽  
Splicing Factor ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Alternative Splice Site

B52 is a Drosophila melanogaster protein that plays a role in general and alternative splicing in vitro. It is homologous to the human splicing factor ASF/SF2 which is essential for an early step(s) in spliceosome assembly in vitro and also regulates 5' and 3' alternative splice site choice in a concentration-dependent manner. In vitro, B52 can function as both a general splicing factor and a regulator of 5' alternative splice site choice. Its activity in vivo, however, is largely uncharacterized. In this study, we have further characterized B52 in vivo. Using Western blot (immunoblot) analysis and whole-mount immunofluorescence, we demonstrate that B52 is widely expressed throughout development, although some developmental stages and tissues appear to have higher B52 levels than others do. In particular, B52 accumulates in ovaries, where it is packaged into the developing egg and is localized to nuclei by the late blastoderm stage of embryonic development. We also overexpressed this protein in transgenic flies in a variety of developmental and tissue-specific patterns to examine the effects of altering the concentration of this splicing factor in vivo. We show that, in many cell types, changing the concentration of B52 adversely affects the development of the organism. We discuss the significance of these observations with regard to previous in vitro results.

Chickpea (Cicer arietinum L.) Lectin Exhibit Inhibition of ACE-I, α-amylase and α-glucosidase Activity

2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  
Keyword(s):  
Biological Effects ◽  
Exchange Chromatography ◽  
Health Concern ◽  
Carbohydrate Binding ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Ic50 Values ◽  
Chickpea Lectin

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.

scholarly journals Modulatory Effects of Osthole on Lipopolysaccharides-Induced Inflammation in Caco-2 Cell Monolayer and Co-Cultures with THP-1 and THP-1-Derived Macrophages

Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 123
Author(s):  
Natalia K. Kordulewska ◽  
Justyna Topa ◽  
Małgorzata Tańska ◽  
Anna Cieślińska ◽  
Ewa Fiedorowicz ◽  
...  
Keyword(s):  
Gene Expression ◽  
Inflammatory Reaction ◽  
Wide Spectrum ◽  
Cell Monolayer ◽  
In Vivo Studies ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Tnf Α

Lipopolysaccharydes (LPS) are responsible for the intestinal inflammatory reaction, as they may disrupt tight junctions and induce cytokines (CKs) secretion. Osthole has a wide spectrum of pharmacological effects, thus its anti-inflammatory potential in the LPS-treated Caco-2 cell line as well as in Caco-2/THP-1 and Caco-2/macrophages co-cultures was investigated. In brief, Caco-2 cells and co-cultures were incubated with LPS to induce an inflammatory reaction, after which osthole (150–450 ng/mL) was applied to reduce this effect. After 24 h, the level of secreted CKs and changes in gene expression were examined. LPS significantly increased the levels of IL-1β, -6, -8, and TNF-α, while osthole reduced this effect in a concentration-dependent manner, with the most significant decrease when a 450 ng/mL dose was applied (p < 0.0001). A similar trend was observed in changes in gene expression, with the significant osthole efficiency at a concentration of 450 ng/μL for IL1R1 and COX-2 (p < 0.01) and 300 ng/μL for NF-κB (p < 0.001). Osthole increased Caco-2 monolayer permeability, thus if it would ever be considered as a potential drug for minimizing intestinal inflammatory symptoms, its safety should be confirmed in extended in vitro and in vivo studies.

scholarly journals The anti-angiogenic isoforms of VEGF in health and disease

2009 ◽  
Vol 37 (6) ◽  
pp. 1207-1213 ◽  
Author(s):  
Yan Qiu ◽  
Coralie Hoareau-Aveilla ◽  
Sebastian Oltean ◽  
Steven J. Harper ◽  
David O. Bates
Keyword(s):  
Splice Site ◽  
Site Selection ◽  
Age Related Macular Degeneration ◽  
Splicing Factor ◽  
Splice Site Selection ◽  
Age Related ◽  
Normal Human ◽  
Radical Revision

Anti-angiogenic VEGF (vascular endothelial growth factor) isoforms, generated from differential splicing of exon 8, are widely expressed in normal human tissues but down-regulated in cancers and other pathologies associated with abnormal angiogenesis (cancer, diabetic retinopathy, retinal vein occlusion, the Denys–Drash syndrome and pre-eclampsia). Administration of recombinant VEGF165b inhibits ocular angiogenesis in mouse models of retinopathy and age-related macular degeneration, and colorectal carcinoma and metastatic melanoma. Splicing factors and their regulatory molecules alter splice site selection, such that cells can switch from the anti-angiogenic VEGFxxxb isoforms to the pro-angiogenic VEGFxxx isoforms, including SRp55 (serine/arginine protein 55), ASF/SF2 (alternative splicing factor/splicing factor 2) and SRPK (serine arginine domain protein kinase), and inhibitors of these molecules can inhibit angiogenesis in the eye, and splice site selection in cancer cells, opening up the possibility of using splicing factor inhibitors as novel anti-angiogenic therapeutics. Endogenous anti-angiogenic VEGFxxxb isoforms are cytoprotective for endothelial, epithelial and neuronal cells in vitro and in vivo, suggesting both an improved safety profile and an explanation for unpredicted anti-VEGF side effects. In summary, C-terminal distal splicing is a key component of VEGF biology, overlooked by the vast majority of publications in the field, and these findings require a radical revision of our understanding of VEGF biology in normal human physiology.

Effect of Auraptene on angiogenesis in Xenograft model of breast cancer

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohammad Reza Shiran ◽  
Elham Mahmoudian ◽  
Abolghasem Ajami ◽  
Seyed Mostafa Hosseini ◽  
Ayjamal Khojasteh ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Gene Expression ◽  
Animal Model ◽  
Protein Expression ◽  
Western Blot ◽  
Xenograft Model ◽  
Dependent Manner ◽  
Concentration Dependent Manner

Abstract Objectives Angiogenesis is the most important challenge in breast cancer treatment. Recently, scientists become interesting in rare natural products and intensive researches was performed to identify their pharmacological profile. Auraptene shows helpful effects such as cancer chemo-preventive, anti-inflammatory, anti-oxidant, immuno-modulatory. In this regard, we investigated the anti-angiogenesis effect of Auraptene in in-vitro and in-vivo model of breast cancer. Methods In this study, 4T, MDA-MB-231 and HUVEC cell lines were used. The proliferation study was done by MTT assay. For tube formation assay, 250 matrigel, 1 × 104 HUVEC treated with Auraptene, 20 ng/mL EGF, 20 ng/mL bFGF and 20 ng/mL VEGF were used. Gene expression of important gene related to angiogenesis in animal model of breast cancer was investigated by Real-time PCR. Protein expression of VCAM-1 and TNFR-1 gene related to angiogenesis in animal model of breast cancer was investigated by western-blot. Results Auraptene treatment led to reduction in cell viability of MDA-MB-231 in a concentration-dependent manner. Also, we observed change in the number of tubes or branches formed by cells incubated with 40 and 80 μM Auraptene. Auraptene effect the gene expression of important gene related to angiogenesis (VEGF, VEGFR2, COX2, IFNɣ). Moreover, the western blot data exhibited that Auraptene effect the protein expression of VCAM-1 and TNFR-1. Conclusions Overall, this study shows that Auraptene significantly suppressed angiogenesis via down-regulation of VEGF, VEGFR2, VCAM-1, TNFR-1, COX-2 and up-regulation of IFNγ.

Factors That Influence Alternative Splice Site Selection in Vitro

1987 ◽  
pp. 97-112 ◽  
Author(s):  
JAMES L. MANLEY ◽  
JONATHAN C.S. NOBLE ◽  
XIN-YUAN FU ◽  
HUI GE
Keyword(s):  
Alternative Splice ◽  
Splice Site ◽  
Site Selection ◽  
Splice Site Selection ◽  
Alternative Splice Site

(-)-Epigallocatechin Gallate Promotes MicroRNA 145 Expression against Myocardial Hypoxic Injury through Dab2/Wnt3a/β-catenin

2020 ◽  
Vol 48 (02) ◽  
pp. 341-356
Author(s):  
Chiu-Mei Lin ◽  
Wei-Jen Fang ◽  
Bao-Wei Wang ◽  
Chun-Ming Pan ◽  
Su-Kiat Chua ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Real Time ◽  
Real Time Pcr ◽  
Myocardial Infarct ◽  
Epigallocatechin Gallate ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Rat Cardiomyocytes

MicroRNA 145 (miR-145) is a critical modulator of cardiovascular diseases. The downregulation of myocardial miR-145 is followed by an increase in disabled-2 (Dab2) expression in cardiomyocytes. (-)-epigallocatechin gallate (EGCG) is a flavonoid that has been evaluated extensively due to its diverse pharmacological properties including anti-inflammatory effects. The aim of this study was to investigate the cardioprotective effects of EGCG under hypoxia-induced stress in vitro and in vivo. The hypoxic insult led to the suppression of miR-145 expression in cultured rat cardiomyocytes in a concentration-dependent manner. Western blotting and real-time PCR were performed. In rat myocardial infarction study, in situ hybridization, and immunofluorescent analyses were adopted. The western blot and real-time PCR data revealed that hypoxic stress with 2.5% O2 suppressed the expression of miR-145 and Wnt3a/[Formula: see text]-catenin in cultured rat cardiomyocytes but augmented Dab2. Treatment with EGCG attenuated Dab2 expression, but increased Wnt3a and [Formula: see text]-catenin in hypoxic cultured cardiomyocytes. Following in vivo myocardial infarction (MI) study, the data revealed the myocardial infarct area reduced by 48.5%, 44.6%, and 48.5% in EGCG (50[Formula: see text]mg/kg) or miR-145 dominant or Dab2 siRNA groups after myocardial infarction for 28 days, respectively. This study demonstrated that EGCG increased miR-145, Wnt3a, and [Formula: see text]-catenin expression but attenuated Dab2 expression. Moreover, EGCG ameliorated myocardial ischemia in vivo. The novel suppressive effect was mediated through the miR-145 and Dab2/Wnt3a/[Formula: see text]-catenin pathways.

scholarly journals Quercetin Is a Flavonoid Breast Cancer Resistance Protein Inhibitor with an Impact on the Oral Pharmacokinetics of Sulfasalazine in Rats

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 397
Author(s):  
Yoo-Kyung Song ◽  
Jin-Ha Yoon ◽  
Jong Kyu Woo ◽  
Ju-Hee Kang ◽  
Kyeong-Ryoon Lee ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Breast Cancer Resistance Protein ◽  
Fold Increase ◽  
Inhibitory Effect ◽  
Dependent Manner ◽  
Cancer Resistance ◽  
Concentration Dependent Manner ◽  
Resistance Protein

The potential inhibitory effect of quercetin, a major plant flavonol, on breast cancer resistance protein (BCRP) activity was investigated in this study. The presence of quercetin significantly increased the cellular accumulation and associated cytotoxicity of the BCRP substrate mitoxantrone in human cervical cancer cells (HeLa cells) in a concentration-dependent manner. The transcellular efflux of prazosin, a stereotypical BCRP substrate, was also significantly reduced in the presence of quercetin in a bidirectional transport assay using human BCRP-overexpressing cells; further kinetic analysis revealed IC50 and Ki values of 4.22 and 3.91 μM, respectively. Moreover, pretreatment with 10 mg/kg quercetin in rats led to a 1.8-fold and 1.5-fold increase in the AUC8h (i.e., 44.5 ± 11.8 min∙μg/mL vs. 25.7 ± 9.98 min∙μg/mL, p < 0.05) and Cmax (i.e., 179 ± 23.0 ng/mL vs. 122 ± 23.2 ng/mL, p < 0.05) of orally administered sulfasalazine, respectively. Collectively, these results provide evidence that quercetin acts as an in vivo as well as in vitro inhibitor of BCRP. Considering the high dietary intake of quercetin as well as its consumption as a dietary supplement, issuing a caution regarding its food–drug interactions should be considered.

Protective Effects on Mitochondria and Anti-Aging Activity of Polysaccharides from Cultivated Fruiting Bodies of Cordyceps militaris

2010 ◽  
Vol 38 (06) ◽  
pp. 1093-1106 ◽  
Author(s):  
Xing-Tai Li ◽  
Hong-Cheng Li ◽  
Chun-Bin Li ◽  
De-Qiang Dou ◽  
Ming-Bo Gao
Keyword(s):  
Hydroxyl Radicals ◽  
Cordyceps Militaris ◽  
Mitochondrial Swelling ◽  
Dependent Manner ◽  
Protective Effects ◽  
Fruiting Bodies ◽  
Concentration Dependent Manner ◽  
Mitochondrial Injury

Cordyceps militaris (L.) Link is an entomopathogenic fungus parasitic to Lepidoptera larvae, and is widely used as a folk tonic or invigorant for longevity in China. Although C. militaris has been used in traditional Chinese medicine for millennia, there is still a lack convincing evidence for its anti-aging activities. This study was performed to investigate the effects of polysaccharides from cultivated fruiting bodies of C. militaris (CMP) on mitochondrial injury, antioxidation and anti-aging activity. Fruiting bodies of C. militaris were cultivated artificially under optimized conditions. The spectrophotometric method was used to measure thiobarbituric acid reactive substances (TBARS), mitochondrial swelling, and activities of scavenging superoxide anions in vitro. D-galactose (100 mg/kg/day) was injected subcutaneously into back of the neck of mice for 7 weeks to induce an aging model. The effects of CMP on the activities of catalase (CAT), surperoxide dismutase (SOD), glutathione peroxidase (GPx) and anti-hydroxyl radicals were assayed in vivo using commercial monitoring kits. The results showed that CMP could inhibit mitochondrial injury and swelling induced by Fe2+ -L-Cysteine in a concentration- dependent manner and it also had a significant superoxide anion scavenging effect. Moreover, the activities of CAT, SOD, GPx and anti-hydroxyl radicals in mice liver were increased significantly by CMP. These results indicate that CMP protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting mitochondrial swelling, and increasing the activities of antioxidases. Therefore, CMP may have pharmaceutical values for mitochondrial protection and anti-aging. CMP was the major bioactive component in C. militaris.

GPR43 REGULATES SODIUM BUTYRATE-INDUCED ANGIOGENESIS AND MATRIX REMODELING

2020 ◽  
Author(s):  
Pollyana Ribeiro Castro ◽  
Lucas Felipe Fernandes Bittencourt ◽  
Sébastien Larochelle ◽  
Silvia Passos Andrade ◽  
Charles Reay Mackay ◽  
...  
Keyword(s):  
Sodium Butyrate ◽  
Granulation Tissue ◽  
Local Treatment ◽  
Dermal Fibroblasts ◽  
Matrix Remodeling ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Fibrovascular Tissue

Butyrate is a short-chain fatty acid (SCFA) derived from microbiota and is involved in a range of cell processes in a concentration-dependent manner. Low concentrations of sodium butyrate (NaBu) was shown to be proangiogenic. However, the mechanisms associated with these effects are not yet fully known. Here, we investigated the contribution of the SCFA receptor GPR43 in the proangiogenic effects of local treatment with NaBu and its effects on matrix remodeling using the sponge-induced fibrovascular tissue model in mice lacking the GPR43 gene (GPR43-KO) and the wild-type (WT). We demonstrated that NaBu (0.2 mM intraimplant) treatment enhanced the neovascularization process, blood flow, and VEGF levels in a GPR43-dependent manner in the implants. Moreover, NaBu was able to modulate matrix remodeling aspects of the granulation tissue such as proteoglycans production, collagen deposition and α-SMA expression in vivo, besides to increase TGF-b1 levels in the fibrovascular tissue, in a GPR43-dependent manner. Interestingly, NaBu directly stimulated L929 murine fibroblasts migration, and TGF-β1 and collagen production in vitro. GPR43 was found to be expressed in human dermal fibroblasts, myofibroblasts and endothelial cells. Overall, our findings evidence that the metabolite-sensing receptor GPR43 contributes to the effects of low dose of NaBu in inducing angiogenesis and matrix remodeling during granulation tissue formation. These data provide important insights for the proposition of new therapeutic approaches based on NaBu, beyond the highly explored intestinal, anti-inflammatory, and anti-cancer purposes, as a local treatment to improve tissue repair, particularly, by modulating granulation tissue components.

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