cdk8 (Proteintech)
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Proteintech
cdk8
Cdk8, supplied by Proteintech, used in various techniques. Bioz Stars score: 93/100, based on 10 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/result/cdk8/product/Proteintech
Average 93 stars, based on 10 article reviews
Cdk8, supplied by Proteintech, used in various techniques. Bioz Stars score: 93/100, based on 10 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/result/cdk8/product/Proteintech
Average 93 stars, based on 10 article reviews
cdk8 - by Bioz Stars,
2026-03
93/100 stars
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1) Product Images from "CDK8 mediated inflammatory microenvironment aggravates osteoarthritis progression"
Article Title: CDK8 mediated inflammatory microenvironment aggravates osteoarthritis progression
Journal: Journal of Advanced Research
doi: 10.1016/j.jare.2025.01.017
Figure Legend Snippet: The overexpression of CDK8 exacerbates knee cartilage degeneration and pain in mice, as well as osteoarthritis in cells. (A) H&E and S-O staining of the knee joints in each group of mice 8 weeks after DMM surgery, (B) followed by assessment of OA severity in the mice using the OARSI scoring system. n = 10 per group. (C) Aggrecan, COL2A1, and MMP-3 expression were detected by immunohistochemical staining in the cartilage samples, (D-F) and quantitative analysis of the proportion of Aggrecan, COL2A1, and MMP-3 positive cells in each segment. n = 6 per group. (G-H) The Pressure Application Measurement (PAM) test and Von Frey filament test were used to assess the pain threshold in mice. (I) C28/I2 cells were transfected with pCMV-control or pCMV-CDK8 and then exposed to IL-1β for 48 h. Western blot analysis was performed to detect aggrecan, COL2A1, SOX9, MMP-3, and MMP-13. (J) C28/I2 and mouse chondrocytes were transfected with pCMV-CDK8 and treated with IL-1β for 7 days. Safranin O and Toluidine Blue staining were used to assess cartilage formation, (K) and the culture supernatants from the last two days were collected to analyze cartilage degradation using the DMMB method to measure GAG content. Data are presented as mean ± SD; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, no significance; comparisons with the control group or as indicated. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Techniques Used: Over Expression, Staining, Expressing, Immunohistochemical staining, Transfection, Control, Western Blot
Figure Legend Snippet: CDK8 knockdown alleviates knee cartilage degeneration and pain in mice and reduces osteoarthritis in cells. (A-B) C28/I2 cells and mouse chondrocytes were transfected with si-CDK8 or si-NC and then exposed to IL-1β for 48 h. (A) qRT-PCR and (B) Western blot analyses were used to detect the expression levels of aggrecan, COL2A1, SOX9, MMP-3, and MMP-13. (C) IF analysis was used to detect the expression of aggrecan and COL2A1 in C28/I2 cells transfected with si-CDK8 or si-NC and exposed to IL-1β for 48 h. (D, E) Safranin O and Toluidine Blue staining were used to assess cartilage formation, analyzed in (D) C28/I2 cells or (E) mouse chondrocytes, both transfected with si-CDK8 and treated with IL-1β for 7 days. (F) Hematoxylin and Eosin (H&E) staining and Safranin O/Fast Green staining of mouse knee joints 8 weeks after DMM surgery, and (G) the severity of osteoarthritis in mice was subsequently assessed using the OARSI scoring system. Each group, n = 6. (H) Pain threshold in mice was assessed using the pressure application measurement (PAM) test. Data are presented as mean ± SD; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, no significance; comparisons with the control group or as indicated. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Techniques Used: Knockdown, Transfection, Quantitative RT-PCR, Western Blot, Expressing, Staining, Control
Figure Legend Snippet: CDK8 is associated with senescence in chondrocytes and regulate their secretion of SASP. (A) Volcano plot of differentially expressed genes from RNA sequencing data. (B) KEGG enrichment analysis of differentially expressed genes. (C-D) GSEA of differentially expressed genes. (E) β-galactosidase staining images of mouse chondrocytes with CDK8 knockdown, co-treated with t-BHP. (F) Representative knee X-rays of patients at different stages of osteoarthritis. According to the Kellgren-Lawrence (KL) grading of the tibiofemoral joint, patients were classified into four stages. Stage I is classified as mild osteoarthritis, n = 23; middle osteoarthritis included stages II and III, n = 29; and stage IV was defined as severe osteoarthritis, n = 35. (G-I) ELISA detection of SASP levels in (G) synovial fluid of patients with mild, moderate, and severe OA, (H) serum of mice, and (I) C28/I2 cells and mouse chondrocytes. Data are presented as mean ± SD; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, no significance; comparisons with the control group or as indicated.
Techniques Used: RNA Sequencing, Staining, Knockdown, Enzyme-linked Immunosorbent Assay, Control
Figure Legend Snippet: CDK8 activates the NF-κB pathway and regulates the transcription of SASP. (A) Western blot assay was used to detect the expression levels of p-IκBα, IκBα, p-p65, and p65. (B) Immunoprecipitation was performed to assess the co-precipitation of CDK8 and p65 in C28/I2 cells treated with or without CDK8-IN-6. (C) Immunofluorescence co-localization was conducted to examine the co-localization of p65 and CDK8 in C28/I2 cells treated with IL-1β for 24 h. (D) C28/I2 cells were transfected with si-CDK8 or pCMV3-CDK8, followed by IL-1β treatment for 24 h, and then subjected to western blot analysis of nuclear and cytoplasmic proteins. (E-F) Dual-luciferase analysis demonstrated NF-κB's regulatory role in SASP transcriptional activation (E) and confirmed the direct binding sites of p65 in the promoters of the IL-6, IL-8, and MMP-13 genes (F), the statistical results indicating the significance of the differences between the truncated promoter groups and the full-length group. (G) Nucleic acid electrophoresis and (H) ChIP-qPCR further investigated the influence of CDK8 on the binding of p65 to SASP promoter region sites in C28/I2 cells. (I) Western blot assay was used to detect the expression levels of Rpb1 CTD, p-Rpb1 CTD (Ser2), and p-Rpb1 CTD (Ser5). Data are presented as mean ± SD; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, no significance; comparisons with the control group or as indicated.
Techniques Used: Western Blot, Expressing, Immunoprecipitation, Immunofluorescence, Transfection, Luciferase, Activation Assay, Binding Assay, Nucleic Acid Electrophoresis, ChIP-qPCR, Control
Figure Legend Snippet: CDK8 and NF-κB are cooperatively recruited to SASP promoters, leading to elongation phosphorylation of the Rpb1 CTD. In C28/I2 cells transfected with si-NC or si-CDK8, with or without IL-1β treatment for one hour, (A–E) ChIP analysis shows the effects of CDK8 knockdown and IL-1β treatment on the binding of p65 (A), CDK8 (B), Rpb1 CTD (C), Rpb1 CTD phosphorylated at Ser5 (D), and Rpb1 CTD phosphorylated at Ser2 (E) to three SASP genes and a housekeeping gene. The gene diagrams are displayed at the top.
Techniques Used: Phospho-proteomics, Transfection, Knockdown, Binding Assay
Figure Legend Snippet: CDK8 promotes the inflammatory microenvironment and osteoclast differentiation of macrophages by regulating the SASP in chondrocytes. (A) Schematic diagram of the migration assay for RAW 264.7 cells. (B-C) Cell migration ability was evaluated using the migration assay (top) and quantification of migrated cells (bottom). (D-E) Western blotting was used to assess the impact of CDK8 on inflammasome activation in murine synovial macrophages. (F-G) The degree of synovitis was evaluated using H&E-stained sections of mouse knee joints. (H and J) TRAP staining was used to detect the extent of osteoclast differentiation. (I and K) The number and average area of TRAP-positive multinucleated osteoclasts were quantified. The number of TRAP-positive osteoclasts with 3–5, 5–10, or more than 10 nuclei was also determined. (L-M) Bone destruction was assessed by microCT of mouse knee joints, with arrows in the figure indicating the medial side of the knee joints. Data are presented as mean ± SD; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, no significance; comparisons with the control group or as indicated.
Techniques Used: Migration, Western Blot, Activation Assay, Staining, Control
Figure Legend Snippet: CDK8 inhibitors alleviated the progression of OA. (A) Molecular structure of CDK8-IN-6. (B) Use the Cell Counting Kit-8 (CCK-8) assay to evaluate the cytotoxic effects of CDK8-IN-6 on C28/I2 cells and mouse chondrocytes at 24 and 48 h. (C-D) C28/I2 cells and mouse chondrocytes were co-treated with IL-1β and CDK8-IN-6 for 48 h. (C) qRT-PCR and (D) Western blot analyses were performed to detect the expression of aggrecan, COL2A1, SOX9, MMP-3, and MMP-13. (E) Immunofluorescence analysis was used to determine the expression of aggrecan and COL2A1 in C28/I2 cells co-treated with IL-1β and CDK8-IN-6 for 48 h. (F, H) Safranin O and Toluidine Blue staining were used to assess cartilage formation in (F) C28/I2 cells and (H) mouse chondrocytes, both treated with IL-1β and CDK8-IN-6 for 7 days. (G, I) The collected supernatants were used to detect GAG content. Data are presented as mean ± SD; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, no significance; comparisons with the control group or as indicated. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Techniques Used: Cell Counting, CCK-8 Assay, Quantitative RT-PCR, Western Blot, Expressing, Immunofluorescence, Staining, Control
Figure Legend Snippet: CDK8-IN-6 selectively inhibits CDK8 to alleviate OA. (A) Docking-predicted binding mode of CDK8 protein with CDK8-IN-6. The overall structure of CDK8 in complex with CDK8-IN-6 in cartoon view. CDK8 and CDK8-IN-6 are colored green and sky blue, respectively (top). Detailed interaction network between CDK8 and CDK8-IN-6, showing all potential binding sites (bottom). (B) Proteins extracted from C28/I2 cells and mouse chondrocytes were used to evaluate the binding of CDK8-IN-6 to CDK8 protein at different concentrations of CDK8-IN-6 and Pronase in DARTS experiments. The binding of CDK8-IN-6 to CDK8 protein was detected by Western blotting. (C) C28/I2 cells were transfected with the indicated CDK8 mutant plasmids for 24 h and subjected to DARTS experiments. Protein expression of the mutated sites was then detected by Western blotting (bottom) and quantified (top). (D) At 8 weeks post-DMM surgery, knee joints from each group of mice were stained with H&E and S-O. (E) Subsequently, the severity of osteoarthritis in mice was assessed using the OARSI scoring system. Each group had n = 10. (F) Expression of Aggrecan, COL2A1, and MMP-3 in cartilage samples was detected by immunohistochemical staining, (G-I) and the proportion of Aggrecan, COL2A1, and MMP-3 positive cells in each section was quantified. Each group had n = 6. (J) Pressure Application Measurement (PAM) test was used to assess the pain threshold in mice. Data are presented as mean ± SD; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ns, no significance; comparisons with the control group or as indicated. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Techniques Used: Binding Assay, Western Blot, Transfection, Mutagenesis, Expressing, Staining, Immunohistochemical staining, Control
