Warnerejlersen6397

Senescence of nucleus pulposus (NP) cells is involved in the pathological process of intervertebral disc degeneration (IVDD). HMG-box transcription factor 1 (HBP1) is a transcriptional inhibitor that prevents proliferation and regulates premature senescence of cells. The aim of this study was to confirm whether HBP1 deficiency could protect stress-induced NP cells premature senescence.

Firstly, HBP1 protein level in human degenerated intervertebral disc tissues was detected. Then, NP cells were isolated from disc samples and transfected with plasmid to upregulate HBP1expression. H2O2 and interleukin-1b (IL-1b) were used to induce NP cells premature senescence in a different manner. Thereafter, cell viability, proliferation, and apoptosis were measured, and the protein expressions of collagen II, HBP1, and p16, were determined by Western blot or immunofluorescence. Finally, the mRNA levels of aggrecan, collagen I, IL-6, Transforming Growth Factor-α (TNF-α), and matrix metalloproteinase-3 (MMP-3) were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR).

The data indicated that HBP1 was upregulated in degenerated NP tissues. HBP1 gene overexpression increased p16 expression, affected NP cell proliferation, and caused cell apoptosis. In addition, HBP1 also decreased the collagen II and aggrecan expressions but increased collagen I, IL-6, TNF-α, and MMP-3 levels. Moreover, the silencing of HBP1 markedly reversed the H2O2 and IL-1b induced NP cell senescence by reducing p16 expression, apoptotic cell population, and inflammatory response and by promoting cell proliferation.

In summary, HBP1 accumulation contributes to the senescence of NP cells, and HBP1 deficiency protects stress-induced NP cells premature senescence.

In summary, HBP1 accumulation contributes to the senescence of NP cells, and HBP1 deficiency protects stress-induced NP cells premature senescence.

To clarify the interaction between TGF-β1 and WISP1, and the effect of Integrin α5/V subunits on the WISP1 caused chondrocyte (CH) dedifferentiated phenotype.

The knee joint cartilage from the trauma and osteoarthritis (OA) patients were collected. The patients of trauma group were confirmed to have no OA history. The protein level of WISP1, Integrin-α5/V, and type II/I collagen were analyzed by Western blotting. Besides, we isolated the CHs from the cartilage without OA and treated CHs with exogenic TGF-β1 and WISP1 protein. selleck inhibitor In addition to this, to regulate the α5 and αV subunits expression of CHs, we silenced two genes by siRNA transfection and upregulated them by exogenic protein supplement. Then, the CHs with different α5 and αV expression were treated with WISP1. To value the chondrogenic gene expression, we determined the type II collagen and SOX9 gene expression by immunofluorescence (IF) and RT-PCR, respectively. Meanwhile, the dedifferentiation markers of CH, type I collagen, and Runx2 expression, Integrin-α5 shows a protective effect during the WISP1 caused CHs dedifferentiation.

TGF-β1 and WISP1 interact to induce CHs dedifferentiation, which was mainly by the mediation of the Integrin-αV subunit. On the contrary, Integrin-α5 shows a protective effect during the WISP1 caused CHs dedifferentiation.

Osteoarthritis (OA) is a common disease in the elderly and seriously affects the quality of life of patients. Tra2β is a protein that has been found to activate PI3K/Akt in recent years. The purpose of this study was to explore the protective effects of Tra2β on chondrocytes and its mechanisms.

The expression of Tra2β in knee cartilage tissue of patients with OA and normal people was compared. In addition, human primary chondrocytes were cultured, the expression of Tra2β in chondrocytes by cell transfection was changed, and its effects on extracellular matrix, inflammation, and apoptosis in chondrocytes were examined. LY294002 was also used to inhibit the activity of PI3K/Akt signaling pathway to verify the mechanism of Tra2β to protect chondrocytes.

The expression of Tra2β in the cartilage tissue of the OA group was significantly lower than that of the control group, and the IL-1β-induced chondrocytes also expressed the lower Tra2β. The overexpression of Tra2β increased the expression of extracellular matrix collagen II and decreased the expressions of MMP3/13, inflammatory factors (IL-6, IL-8 and TNF-α), and apoptotic factors (caspase3/9, Bax). In addition, the overexpression of Tra2β also increased expression and phosphorylation of PI3K and Akt. However, LY294002 attenuated the protective effect of Tra2β on chondrocytes by inhibiting the PI3K/Akt signaling pathway.

Tra2β activates the PI3K/Akt signaling pathway, reduces the degradation of extracellular matrix of chondrocytes, reduces the level of inflammation and apoptosis of chondrocytes, and thus, plays a role in the treatment of OA.

Tra2β activates the PI3K/Akt signaling pathway, reduces the degradation of extracellular matrix of chondrocytes, reduces the level of inflammation and apoptosis of chondrocytes, and thus, plays a role in the treatment of OA.

To explore the effect of collagen IX alpha 3 chain (COL9A3) gene silencing on apoptosis of nucleus pulposus cells in rats with intervertebral disc degeneration (IVDD) and its regulatory mechanism, so as to provide potential reference for the treatment of IVDD.

The model of IVDD in rats were constructed to isolate, culture and identify nucleus pulposus cells for subsequent experiment. With the construction of lentivirus vectors, cells were divided into Blank group, negative control (NC) group, COL9A3 shRNA group, COL9A3 overexpression group, mitogen-activated protein kinase (MAPK) pathway inhibitor (Theaflavin 3,3'-digallate, TF3) group and COL9A3 shRNA+TF3 group according to different transfection treatments. After cell transfection, the expression of COL9A3, extracellular regulated protein kinase 1/2 (ERK1/2) and phosphorylated-ERK1/2 (p-ERK1/2), MEK1/2 and p-MEK1/2, as well apoptosis related indexes were detected by using quantitative real-time PCR (qRT-PCR) and Western Blot. Furthermore, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect the proliferation of transfected cells, and flow cytometry to detect changes of cell cycle and apoptosis.