Transforming growth factor-β1-regulated Fas/FasL pathway activation suppresses nucleus pulposus cell apoptosis in an inflammatory environment

Abstract Background: During disc degeneration, inflammatory cytokine tumor necrosis factor (TNF)-α is correlated with nucleus pulposus (NP) cell apoptosis. Transforming growth factor (TGF)-β1 has the potential to regenerate degenerative disc. Objective: To investigate the protective role of TGF-β1 against TNF-α-mediated NP cell apoptosis and the underlying mechanism. Methods: Rat NP cells were treated with TNF-α (100 ng/ml) for 48 h. TGF-β1 was added into the culture medium to investigate its protective effects against TNF-α-induced NP cell apoptosis. Exogenous FasL was used to investigate the potential role of the Fas/FasL pathway in this process. Flow cytometry assay was used to analyze NP cell apoptosis. Real-time PCR and Western blotting were used to analyze gene and protein expression of apoptosis-related molecules. Results: In TNF-α-treated NP cells, TGF-β1 significantly decreased NP cell apoptosis, declined caspase-3 and -8 activity, and decreased expression of Bax and caspase-3 (cleaved-caspase-3) but increased expression of Bcl-2. However, exogenous FasL partly reversed these effects of TGF-β1 in NP cells treated with TNF-α. Additionally, expression of Fas and FasL in TNF-α-treated NP cells partly decreased by TGF-β1, whereas exogenous FasL increased expression of Fas and FasL in NP cells treated with TGF-β1 and TNF-α. Conclusion: TGF-β1 helps to inhibit TNF-α-induced NP cell apoptosis and the Fas/FasL pathway may be involved in this process. The present study suggests that TGF-β1 may be effective to retard inflammation-mediated disc degeneration.

Download Full-text

Mechano growth factor attenuates mechanical overload-induced nucleus pulposus cell apoptosis through inhibiting the p38 MAPK pathway

Bioscience Reports ◽

10.1042/bsr20182462 ◽

2019 ◽

Vol 39 (3) ◽

Cited By ~ 4

Author(s):

Qing Xu ◽

Haolin Fang ◽

Liang Zhao ◽

Cunxin Zhang ◽

Luo Zhang ◽

...

Keyword(s):

Growth Factor ◽

Protein Expression ◽

Nucleus Pulposus ◽

P38 Mapk ◽

Disc Degeneration ◽

Cell Apoptosis ◽

Caspase 3 ◽

Mapk Pathway ◽

P38 Mapk Pathway ◽

Mechanical Overload

Abstract Mechanical overload is a risk factor of disc degeneration. It can induce disc degeneration through mediating cell apoptosis. Mechano growth factor (MGF) has been reported to inhibit mechanical overload-induced apoptosis of chondrocytes. The present study is aimed to investigate whether MGF can attenuate mechanical overload-induced nucleus pulposus (NP) cell apoptosis and the possible signaling transduction pathway. Rat NP cells were cultured and subjected to mechanical overload for 7 days. The control NP cells did not experience mechanical load. The exogenous MGF peptide was added into the culture medium to investigate its protective effects. NP cell apoptosis ratio, caspase-3 activity, gene expression of Bcl-2, Bax and caspase-3, protein expression of cleaved caspase-3, cleaved PARP, Bax and Bcl-2 were analyzed to evaluate NP cell apoptosis. In addition, activity of the p38 MAPK pathway was also detected. Compared with the control NP cells, mechanical overload significantly increased NP cell apoptosis and caspase-3 activity, up-regulated gene/protein expression of pro-apoptosis molecules (i.e. Bax, caspase-3, cleaved caspase-3 and cleaved PARP) whereas down-regulated gene/protein expression of anti-apoptosis molecule (i.e. Bcl-2). However, exogenous MGF partly reversed these effects of mechanical overload on NP cell apoptosis. Further results showed that activity of the p38 MAPK pathway of NP cells cultured under mechanical overload was decreased by addition of MGF peptide. In conclusion, MGF is able to attenuate mechanical overload-induced NP cell apoptosis, and the p38 MAPK signaling pathway may be involved in this process. The present study provides that MGF supplementation may be a promising strategy to retard mechanical overload-induced disc degeneration.

Download Full-text

Melatonin Suppresses Apoptosis of Nucleus Pulposus Cells through Inhibiting Autophagy via the PI3K/Akt Pathway in a High-Glucose Culture

BioMed Research International ◽

10.1155/2021/4604258 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Jian Li ◽

Chengqiang Wang ◽

Lixin Xue ◽

Fan Zhang ◽

Jianqiang Liu

Keyword(s):

Protein Expression ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

High Glucose ◽

Cell Apoptosis ◽

Caspase 3 ◽

Akt Pathway ◽

Protective Effects ◽

Nucleus Pulposus Cells

Diabetes mellitus- (DM-) associated hyperglycemia promotes apoptosis of disc nucleus pulposus (NP) cells, which is a contributor to intervertebral disc degeneration (IDD). Melatonin is able to protect against cell apoptosis. However, its effects on apoptosis of NP cell in a high-glucose culture remain unclear. The purpose of the present study was to investigate the effects and molecular mechanism of melatonin on NP cell apoptosis in a high-glucose culture. NP cells were cultured in the baseline medium supplemented with a high-glucose concentration (0.2 M) for 3 days. The control cells were only cultured in the baseline medium. Additionally, the pharmaceutical inhibitor LY294002 was added along with the culture medium to investigate the possible role of the PI3K/Akt pathway. Apoptosis, autophagy, and activity of the PI3K/Akt pathway of NP cells among these groups were evaluated. Compared with the control NP cells, high glucose significantly increased cell apoptosis ratio and caspase-3/caspase-9 activity and decreased mRNA expression of Bcl-2, whereas it increased mRNA or protein expression of Bax, caspase-3, cleaved caspase-3, cleaved PARP, and autophagy-related molecules (Atg3, Atg5, Beclin-1, and LC3-II) and decreased protein expression of p-Akt compared with the control cells. Additionally, melatonin partly inhibited the effects of high glucose on those parameters of cell apoptosis, autophagy, and activation of PI3K/Akt. In conclusion, melatonin attenuates apoptosis of NP cells through inhibiting the excessive autophagy via the PI3K/Akt pathway in a high-glucose culture. This study provides new theoretical basis of the protective effects of melatonin against disc degeneration in a DM patient.

Download Full-text

Scutellarin-induced A549 cell apoptosis depends on activation of the transforming growth factor-β1/smad2/ROS/caspase-3 pathway

Open Life Sciences ◽

10.1515/biol-2021-0085 ◽

2021 ◽

Vol 16 (1) ◽

pp. 961-968

Author(s):

Guang-Yan Zhang ◽

Wei-Yong Chen ◽

Xiao-Bo Li ◽

Hua Ke ◽

Xue-Lin Zhou

Keyword(s):

Growth Factor ◽

Cell Viability ◽

A549 Cell ◽

Cell Apoptosis ◽

Caspase 3 ◽

Transforming Growth Factor ◽

A549 Cells ◽

Ros Production ◽

Intracellular Ros ◽

Tgf Β1

Abstract Scutellarin plays an anti-tumor role in A549 lung cancer cells, but the underlying mechanism is unclear. In this study, scutellarin was used to treat A549 cells for 12, 24, and 48 h, followed by the addition of Tempo, a selective scavenger of mitochondrial reactive oxygen species (ROS) and SB431542, a transforming growth factor (TGF)-β1 receptor inhibitor. A dihydroethidium fluorescence probe was used to measure the intracellular ROS level, Cell Counting Kit-8 (CCK-8) was used to detect cell viability, and flow cytometry was performed to examine apoptosis. Western blots were used to detect the total protein level of TGF-β1, p-smad2, and cleaved caspase-3 in A549 cells. The results showed that scutellarin significantly inhibited cell viability and increased apoptosis. Scutellarin also promoted intracellular ROS production, TGF-β1/smad2 signaling pathway activation, and cleaved caspase-3 expression, which was partly reversed by Tempo. Moreover, scutellarin-induced intracellular ROS production and cleaved caspase-3 expression were inhibited by blocking the TGF-β1/smad2 pathway with SB431542. In conclusion, scutellarin promoted apoptosis and intracellular ROS accumulation, which could be abrogated by Tempo and SB431542 treatment in A549 cells. Our study indicated that scutellarin induced A549 cell apoptosis via the TGF-β1/smad2/ROS/caspase-3 pathway.

Download Full-text

Expression of miR-195 and its target gene Bcl-2 in human intervertebral disc degeneration and their effects on nucleus pulposus cell apoptosis

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02538-8 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Xue-Lin Lin ◽

Zhao-Yun Zheng ◽

Qing-Shan Zhang ◽

Zhen Zhang ◽

You-Zhi An

Keyword(s):

Cell Proliferation ◽

Intervertebral Disc ◽

Nucleus Pulposus ◽

Disc Degeneration ◽

Rat Model ◽

Cell Apoptosis ◽

Intervertebral Disc Degeneration ◽

Target Gene ◽

Blank Group ◽

Tnf Α

Abstract Objective To investigate the expression of miR-195 and its target gene Bcl-2 in intervertebral disc degeneration (IVDD) and its effect on nucleus pulposus (NP) cell apoptosis. Methods The expressions of miR-195 and Bcl-2 in NP tissues of IVDD patients were quantified by qRT-PCR and western blotting, respectively. NP cells were divided into blank group, TNF-α group, TNF-α + miR-NC group, TNF-α + siBcl-2 group, and TNF-α + miR-195 inhibitors + siBcl-2 group. Cell proliferation was detected by MTT assay, cell apoptosis evaluated by flow cytometry, and mitochondrial membrane potential (MMP) tested by JC-1 staining. Moreover, the function of miR-195 on IVDD in vivo was investigated using a puncture-induced IVDD rat model. Results IVDD patients had significantly increased miR-195 expression and decreased Bcl-2 protein expression in NP tissues. The expression of miR-195 was negatively correlated with the expression of Bcl-2 in IVDD patients. Dual-luciferase reporter gene assay indicated that Bcl-2 was a target gene of miR-195. In comparison with blank group, TNF-α group showed decreased cell proliferation and MMP, increased cell apoptosis, upregulated expression of miR-195, Bax, and cleaved caspase 3, and downregulated Bcl-2 protein, while these changes were attenuated by miR-195 inhibitors. Additionally, siBcl-2 can reverse the protective effect of miR-195 inhibitors on TNF-α-induced NP cells. Besides, inhibition of miR-195 alleviated IVDD degeneration and NP cell apoptosis in the rat model. Conclusion MiR-195 was significantly upregulated in NP tissues of IVDD patients, and inhibition of miR-195 could protect human NP cells from TNF-α-induced apoptosis via upregulation of Bcl-2.

Download Full-text

Identification of a microRNA signature in renal fibrosis: role of miR-21

AJP Renal Physiology ◽

10.1152/ajprenal.00273.2011 ◽

2011 ◽

Vol 301 (4) ◽

pp. F793-F801 ◽

Cited By ~ 169

Author(s):

Abolfazl Zarjou ◽

Shanzhong Yang ◽

Edward Abraham ◽

Anupam Agarwal ◽

Gang Liu

Keyword(s):

Epithelial Cells ◽

Renal Fibrosis ◽

Transforming Growth Factor ◽

Response To Treatment ◽

Tubular Epithelial Cells ◽

Altered Expression ◽

Tnf Α ◽

Tgf Β1

Renal fibrosis is a final stage of many forms of kidney disease and leads to impairment of kidney function. The molecular pathogenesis of renal fibrosis is currently not well-understood. microRNAs (miRNAs) are important players in initiation and progression of many pathologic processes including diabetes, cancer, and cardiovascular disease. However, the role of miRNAs in kidney injury and repair is not well-characterized. In the present study, we found a unique miRNA signature associated with unilateral ureteral obstruction (UUO)-induced renal fibrosis. We found altered expression in UUO kidneys of miRNAs that have been shown to be responsive to stimulation by transforming growth factor (TGF)-β1 or TNF-α. Among these miRNAs, miR-21 demonstrated the greatest increase in UUO kidneys. The enhanced expression of miR-21 was located mainly in distal tubular epithelial cells. miR-21 expression was upregulated in response to treatment with TGF-β1 or TNF-α in human renal tubular epithelial cells in vitro. Furthermore, we found that blocking miR-21 in vivo attenuated UUO-induced renal fibrosis, presumably through diminishing the expression of profibrotic proteins and reducing infiltration of inflammatory macrophages in UUO kidneys. Our data suggest that targeting specific miRNAs could be a novel therapeutic approach to treat renal fibrosis.

Download Full-text

The role of TGF-β2 in cartilage development and diseases

Bone and Joint Research ◽

10.1302/2046-3758.108.bjr-2021-0086 ◽

2021 ◽

Vol 10 (8) ◽

pp. 474-487

Author(s):

Mengmeng Duan ◽

Qingxuan Wang ◽

Yang Liu ◽

Jing Xie

Keyword(s):

Growth Factor ◽

Transforming Growth Factor ◽

Vital Role ◽

Cartilage Defects ◽

Cartilage Development ◽

Physiological Processes ◽

Cartilage Diseases ◽

Autologous Mesenchymal Stem Cells ◽

Tgf Β1

Transforming growth factor-beta2 (TGF-β2) is recognized as a versatile cytokine that plays a vital role in regulation of joint development, homeostasis, and diseases, but its role as a biological mechanism is understood far less than that of its counterpart, TGF-β1. Cartilage as a load-resisting structure in vertebrates however displays a fragile performance when any tissue disturbance occurs, due to its lack of blood vessels, nerves, and lymphatics. Recent reports have indicated that TGF-β2 is involved in the physiological processes of chondrocytes such as proliferation, differentiation, migration, and apoptosis, and the pathological progress of cartilage such as osteoarthritis (OA) and rheumatoid arthritis (RA). TGF-β2 also shows its potent capacity in the repair of cartilage defects by recruiting autologous mesenchymal stem cells and promoting secretion of other growth factor clusters. In addition, some pioneering studies have already considered it as a potential target in the treatment of OA and RA. This article aims to summarize the current progress of TGF-β2 in cartilage development and diseases, which might provide new cues for remodelling of cartilage defect and intervention of cartilage diseases.

Download Full-text

Abstract 17285: A Selective Transforming Growth Factor-β and Growth Differentiation Factor-15 Ligand Trap Attenuates Pulmonary Hypertension

Circulation ◽

10.1161/circ.130.suppl_2.17285 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

Lai-Ming Yung ◽

Samuel D Paskin-Flerlage ◽

Ivana Nikolic ◽

Scott Pearsall ◽

Ravindra Kumar ◽

...

Keyword(s):

Growth Factor ◽

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Type I ◽

Rna Seq ◽

Differentiation Factor ◽

Group I ◽

Tgf Β1

Introduction: Excessive Transforming Growth Factor-β (TGF-β) signaling has been implicated in pulmonary arterial hypertension (PAH), based on activation of TGF-β effectors and transcriptional targets in affected lungs and the ability of TGF-β type I receptor (ALK5) inhibitors to improve experimental PAH. However, clinical use of ALK5 inhibitors has been limited by cardiovascular toxicity. Hypothesis: We tested whether or not selective blockade of TGF-β and Growth Differentiation Factor (GDF) ligands using a recombinant TGFβ type II receptor extracellular domain Fc fusion protein (TGFBRII-Fc) could impact experimental PAH. Methods: Male SD rats were injected with monocrotaline (MCT) and received vehicle or TGFBRII-Fc (15 mg/kg, twice per week, i.p.). C57BL/6 mice were treated with SU-5416 and hypoxia (SUGEN-HX) and received vehicle or TGFBRII-Fc. RNA-Seq was used to profile transcriptional changes in lungs of MCT rats. Circulating levels of GDF-15 were measured in 241 PAH patients and 41 healthy controls. Human pulmonary artery smooth muscle cells were used to examine signaling in vitro . Results: TGFBRII-Fc is a selective ligand trap, inhibiting the ability of GDF-15, TGF-β1, TGF-β3, but not TGF-β2 to activate SMAD2/3 in vitro . In MCT rats, prophylactic treatment with TGFBRII-Fc normalized expression of TGF-β transcriptional target PAI-1, attenuated PAH and vascular remodeling. Delayed administration of TGFBRII-Fc in rats with established PAH at 2.5 weeks led to improved survival, decreased PAH and remodeling at 5 weeks. Similar findings were observed in SUGEN-HX mice. No valvular abnormalities were found with TGFBRII-Fc treatment. RNA-Seq revealed GDF-15 to be the most highly upregulated TGF-β ligand in the lungs of MCT rats, with only modest increases in TGF-β1 and no change in TGF-β2/3 observed, suggesting a dominant role of GDF-15 in the pathophysiology of this model. Plasma levels of GDF-15 were significantly increased in patients with diverse etiologies of WHO Group I PAH. Conclusions: These findings demonstrate that a selective TGF-β/GDF-15 trap attenuates experimental PAH, remodeling and mortality, without causing valvulopathy. These data highlight the potential role of GDF-15 as a pathogenic molecule and therapeutic target in PAH.

Download Full-text

Centrifugation Conditions in the L-PRP Preparation Affect Soluble Factors Release and Mesenchymal Stem Cell Proliferation in Fibrin Nanofibers

Molecules ◽

10.3390/molecules24152729 ◽

2019 ◽

Vol 24 (15) ◽

pp. 2729 ◽

Cited By ~ 4

Author(s):

Melo ◽

Luzo ◽

Lana ◽

Santana

Keyword(s):

Growth Factor ◽

Transforming Growth Factor ◽

Platelet Rich Plasma ◽

Clinical Practices ◽

Soluble Factors ◽

Tnf Α ◽

Platelet Concentration ◽

Tgf Β1

Leukocyte and platelet-rich plasma (L-PRP) is an autologous product that when activated forms fibrin nanofibers, which are useful in regenerative medicine. As an important part of the preparation of L-PRP, the centrifugation parameters may affect the release of soluble factors that modulate the behavior of the cells in the nanofibers. In this study, we evaluated the influences of four different centrifugation conditions on the concentration of platelets and leukocytes in L-PRP and on the anabolic/catabolic balance of the nanofiber microenvironment. Human adipose-derived mesenchymal stem cells (h-AdMSCs) were seeded in the nanofibers, and their viability and growth were evaluated. L-PRPs prepared at 100× g and 100 + 400× g released higher levels of transforming growth factor (TGF)-β1 and platelet-derived growth factor (PDGF)-BB due to the increased platelet concentration, while inflammatory cytokines interleukin (IL)-8 and tumor necrosis factor (TNF)-α were more significantly released from L-PRPs prepared via two centrifugation steps (100 + 400× g and 800 + 400× g) due to the increased concentration of leukocytes. Our results showed that with the exception of nanofibers formed from L-PRP prepared at 800 + 400× g, all other microenvironments were favorable for h-AdMSC proliferation. Here, we present a reproducible protocol for the standardization of L-PRP and fibrin nanofibers useful in clinical practices with known platelet/leukocyte ratios and in vitro evaluations that may predict in vivo results.

Download Full-text

Resveratrol inhibits IL-1β-mediated nucleus pulposus cell apoptosis through regulating the PI3K/Akt pathway

Bioscience Reports ◽

10.1042/bsr20190043 ◽

2019 ◽

Vol 39 (3) ◽

Cited By ~ 9

Author(s):

Yanhai Jiang ◽

Zhijie Xie ◽

Jinying Yu ◽

Lianqiang Fu

Keyword(s):

Nucleus Pulposus ◽

Disc Degeneration ◽

Cell Apoptosis ◽

Inflammatory Cytokine ◽

Culture Medium ◽

Caspase 3 ◽

Signal Transduction Pathway ◽

Akt Pathway ◽

Protective Effects ◽

Apoptosis Ratio

Abstract Nucleus pulposus (NP) cell apoptosis is a classical cellular character during intervertebral disc degeneration (IDD). Previous studies have shown that inflammatory cytokine-induced NP cell apoptosis plays an important role in disc degeneration. The present study was aimed to investigate whether resveratrol can suppress IL-1β-mediated NP cell apoptosis and the potential signal transduction pathway. Experimental rat NP cells were treated with culture medium containing IL-1β (20 ng/ml) for 7 days. Control NP cells were cultured in the baseline medium. Resveratrol was added along with culture medium to investigate its effects. The inhibitor LY294002 was used to study the role of the PI3K/Akt pathway. NP cell apoptosis was reflected by the caspase-3 activity, cell apoptosis ratio, and expression of apoptosis-related molecules (Bcl-2, Bax, caspase-3, cleaved caspase-3, and cleaved PARP). Compared with the control NP cells, IL-1β significantly increased caspase-3 activity, NP cell apoptosis ratio and mRNA/protein expression of Bax, caspase-3, cleaved caspase-3 and cleaved PARP, but decreased mRNA expression of Bcl-2. However, resveratrol partly suppressed the effects of IL-1β on those cell apoptosis-related parameters. Further analysis showed that IL-1β significantly decreased activity of the PI3K/Akt pathway whereas resveratrol partly increased activity of the PI3K/Akt pathway in NP cells treated with IL-1β. Additionally, when the inhibitor LY294002 was added along with the resveratrol, its protective effects against IL-1β-induced NP cell apoptosis were attenuated. In conclusion, resveratrol suppresses IL-1β-mediated NP cell apoptosis through activating the PI3K/Akt pathway. Resveratrol may be an effective drug to attenuate inflammatory cytokine-induced disc degenerative changes.

Download Full-text