Effect Of Biglycan Research Articles

Effect of biglycan on apoptosis of neurons in acute cerebral infarction in rats

ObjectiveTo investigate the effect and mechanism of biglycan (BGN) on apoptosis after experimental acute cerebral infarction (CI) in rat.MethodsA total of 110 clean grade Wistar male rats were randomly divided as follow: A total of 80 clean grade Wistar male rats were randomly divided into sham group and CI group consisted of 3h, 6 h, 12h, 24h, 48h, 72h, and 7d (n=10). The expression of BGN in neuron and its time course were detected. A total of 30 clean grade Wistar male rats were randomly divided into sham group, sham + control lentivirus group, sham + BGN lentivirus group, CI + control lentivirus group, and CI + BGN lentivirus group (n=6). The silence efficiency of BGN and the effect of BGN on neuronal apoptosis and neurological score after CI were detected. CI model was induced by reforming longa method. Lentiviral vector was administered intracerebroventricularly 7 days before CI. The expression of protein and mRNA of BGN were detected by western blot and real‐time quantitative PCR (qRT‐PCR). Immunofluorescence was conducted to explore the expression of BGN on neuron. Neurological score was detected by the modified Garcia score, beam balance tests and Longa’s Five‐Point Pacification Low. The TUNEL was used to detect neuronal apoptosis.ResultsThe expression of protein and mRNA of BGN were peaked at 24h after CI (P<0.05). A majority of BGN were detected on neuron at 24 h after CI. Compared with CI + control lentivirus group, the modified Garcia score, beam balance tests and the Longa’s Five‐Point Pacification were significantly improved in CI + BGN lentivirus group (P<0.05), as well as the TUNEL‐positive neurons ratio was significantly decreased ( P<0.05).ConclusionInhibition of BGN can significantly reduce early neuronal apoptosis after CI, and attenuated neurological deficits.Support or Funding InformationThis study was supported by the National Natural Science Foundation Youth Fund (30600637), China Postdoctral Foundation (2014M561207, 2019T120195), the Shanxi Province Basic Research Program (2010021034‐4, 201601D011119), the Shanxi Scholarship Council of China (2011‐096 and Key Projects No.4), Department of Human Resources and Social Security of Shanxi province, The science and technology research projects of health department of Shanxi Province (2016D011119), The Teaching Reform Program of Shanxi Higher Education, The Education Reform Project of Postgraduate Students in Shanxi Province, Lvliang people’s hospital fund, The Education Reform Project of Shanxi Medical University.

Biglycan protects human neuroblastoma cells from nitric oxide-induced death by inhibiting AMPK-mTOR mediated autophagy and intracellular ROS level.

The ubiquitous proteoglycan, biglycan (BGN) acts as an important modulator, regulating key molecular pathways of metabolism and brain function. Autophagy is documented as a defining feature of neurodegeneration in Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). In the present study, we found that BGN protected neuronal cells from nitric oxide (NO)-induced cell apoptosis. However, it is still unclear that whether the neuroprotective effect of BGN relates to autophagy. Here, we discovered that an NO donor, sodium nitroprusside (SNP) induced autophagy in human SH-SY5Y neuroblastoma cells, including activating LC3B and inhibiting p62. Inhibiting autophagy by 3MA aggravated NO-induced cell death, otherwise promoting autophagy by Rapamycin rescued NO-triggered cell death. Notably, BGN downregulated by NO, significantly protected SH-SY5Y cells against NO-induced neurotoxicity by inhibiting the activation of autophagy-dependent AMPK signaling pathway. Moreover, BGN overexpression also diminished NO-induced the elevation of intracellular reactive oxygen species (ROS) level, but not NO content. These findings suggest that BGN protects neuroblastoma cells from NO-induced death by suppressing autophagy-dependent AMPK-mTOR signaling and intracellular ROS level.

Enhancement of tenogenic differentiation of rat tendon-derived stem cells by biglycan.

Biglycan (BGN) has been identified as one of the critical components of the tendon-derived stem cells (TDSCs) niche and may be related to tendon formation. However, so far, no study has demonstrated whether the soluble BGN could induce the tenogenic differentiation of TDSCs in vitro. The aim of this study was to investigate the effect of BGN on the tenogenic differentiation of TDSCs. The proliferation and tenogenic differentiation of TDSCs exposed to different concentrations of BGN (0, 50, 100, and 500 ng/ml) were determined by the live/dead cell staining assay, CCK-8 assay, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis. The BGN signaling pathway of TDSCs (with and without 50 ng/ml of BGN) was determined by western blot analysis and qRT-PCR analysis. At a concentration of 50 ng/ml, BGN increased the expression of the tenogenic markers THBS-4 and TNMD at both the messenger RNA (mRNA) and protein levels. Meanwhile, 50 ng/ml of BGN inhibited the expression of the chondrogenic and osteogenic markers SOX9, ACN, and RUNX2 at both the mRNA and protein levels. Moreover, BGN (50 ng/ml) affected the expression of the components of the extracellular matrix of TDSCs. Additionally, BGN activated the Smad1/5/8 pathway as indicated by an increase in phosphorylation and demonstrated by inhibition experiments. Upregulation in the gene expression of BMP-associated receptors (BMPRII, ActR-IIa, and BMPR-Ib) and Smad pathway components (Smad4 and 8) was observed. Taken together, BGN regulates tenogenic differentiation of TDSCs via BMP7/Smad1/5/8 pathway and this regulation may provide a basic insight into treating tendon injury.

Biglycan, a Nitric Oxide-Downregulated Proteoglycan, Prevents Nitric Oxide-Induced Neuronal Cell Apoptosis via Targeting Erk1/2 and p38 Signaling Pathways.

Nitric oxide (NO), a gaseous signaling molecule, induces apoptosis and mediates neurodegenerative diseases and brain injury. Biglycan (BGN), a member of the small leucine-rich proteoglycan family, was demonstrated to exert anti-apoptosis function in various disease models. However, little is known about the effect of BGN on NO-induced neurotoxicity. Here, for the first time, we reported that BGN protects against NO-induced apoptosis in human neuroblastoma SH-EP1 cells. This is supported by the finding that sodium nitroprusside (SNP), a NO donor, triggered downregulation of BGN in SH-EP1 cells, and over-expression of BGN strikingly attenuated NO-induced nuclear fragmentation and apoptosis of neuronal cells. More importantly, BGN remarkably blocked NO-induced phosphorylation of Erk1/2 and p38 signaling, but not JNK MAPK pathway in neuronal cells. Furthermore, inhibiting Erk1/2 by U0126 or p38 by SB203580 partially protected against NO-induced cell death. Conversely, downregulation of BGN by siRNA aggravated NO-induced neuronal cell death, which was not attenuated by U0126 or SB203580. These findings indicated that BGN, downregulated by NO, prevents NO-induced neuronal cell apoptosis via targeting Erk1/2 and p38 signaling pathways. Our results strongly suggest that BGN could be explored for the prevention of NO-induced neurodegenerative disorders.

Effect of biglycan on melanoma invasiveness via increased tissue stiffness and integrin-β1 expression.

11526Background: A better understanding of the biology of the melanoma microenvironment may help to develop new therapeutic strategies. The expression level of the extracellular matrix molecule big...

Biglycan enhances the ability of migration and invasion in endometrial cancer.

This study aimed to confirm that biglycan (BGN) can promote the migration and invasion in endometrial cancer both in vitro and in vivo and the possible therapeutic value of BGN in endometrial cancer. Western blot was used to screen out the higher protein level of BGN in human endometrial cancer cells; BGN knocked down cells were constructed by lentiviral transfection; The effect of BGN in endometrial cancer detected by wound healing, transwell migration, and invasion, endothelial tube formation assay in vitro, and xenograft model in vivo. (1) We found that BGN expression level is higher in the Ishikawa (ISK, high differentiation) and AN3CA (poor differentiation) cells than other endometrial cancer cells. (2) BGN enhances endometrial cancer cell wound healing, invasion, and migration ability and formation ability of endothelial cells in vitro. Xenograft model has confirmed the outcome in vivo. BGN might play an important role on metastasis in human endometrial cancer and it might be a target marker for the molecular therapy of advanced and recurrence endometrial cancer.

P148Cardiac myocytes are protected by small leucine rich proteoglycans against simulated ischemia/reperfusion injury

It was previously shown by our group that the overexpression of biglycan in a transgenic mouse model enhances the induction of cardioprotective genes. Ischemia induced cell death was decreased by bigylcan treatment in neonatal cardiomyocytes. In this study we aimed to test whether the biglycan core protein or the glycosaminoglycan is responsible for the cardioprotective effect of biglycan. We also investigated whether decorin, (which has a similar structure to biglycan), has any cardio-protective effects on cardiomyocytes during simulated ischemia/reperfusion (SI/R) injury. Primary cardiomyocyte cultures were isolated from neonatal rat hearts. The 2 day-old cultures were pretreated with 0, 1, 3, 10, 30, and 100 nM decorin, biglycan, biglycan core protein or chondroitin sulfate A for 20 hours followed by an SI/R protocol. The treatment was maintained throughout SI , 240 min, hypoxic solution, hypoxic chamber gassed with 95% N2 es 5% CO2) and reperfusion (120 min, normoxic conditions, medium). At the end of the protocol, a viability assay was performed using calcein staining. Compared to the normoxic untreated control, approximately 40% of the cardiomyocytes died during the simulated ischemia/reperfusion injury. Doses of 10 and 30 nM biglycan increased cell viability significantly, compared to SI/R control (29±4 and 18±5%). The biglycan core protein showed similar cytoprotective effects at 3 and 10 nM doses (21±4 and 24±5%), however, the chondroitin sulfate had no influence on the viability of cardiomyocytes. In the case of decorin, the 3 and 10 nM doses significantly increased the survival of the cells (28±3 and 20±4%). Based on our experiments, we concluded that both decorin and biglycan exert a cyto-protective effect on cardiomyocytes against SI/R injury and this protective effect of biglycan is likely due to the biglycan core protein. Grants: NKTM-OTKA-PD-106001, South-East European Foundation Lykeon Scholarship, GA holds Bolyai Janos Fellowship

Interleukin1‐Induced apoptosis of keratocytes: effect of biglycan

Abstract Purpose: Biglycan is absent in the normal cornea, but UVR exposure leads to a significant expression of the biglycan gene in the rabbit cornea, an effect that decreases after healing is completed, indicating the envolvement of biglycan in the corneal repair process. In the present study, we have investigated possible involvement of biglycan in the modulation of the survival of keratocytes. Methods: Keratocytes were grown either under serum free conditions to obtain quiescent keratocyte cell culture or in the presence of 10% fetal bovine serum to induce keratocyte transformation into myofibroblasts. Myofibroblastic phenotype was confirmed by immunocytochemistry with anti‐alpha‐smooth muscle actin antibodies. Cell death was induced in both cell cultures by interleukin‐1 in the presence or absence of biglycan.Histone‐associated DNA fragments were assayed by using a cell death detection ELISA. Results: Quantification of histone‐associated DNA fragments by the cell death detection ELISA showed that biglycan strongly protected quiescent keratocytes from dying whereas it enhanced the death rate of transformed keratocytes. Apoptotic death rate was elevated after the addition of IL‐1 in both keratocyte and myofibroblast cell cultures. Co‐incubation with biglycan markedly reduced the number of apoptotic keratocytes but markedly increased the number of apoptotic myofibroblasts. Conclusions: IL‐1‐induces apoptosis of both quiescent and transformed keratocytes. However, biglycan has differential effect on apoptosis of these two cell types.