Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Nov 8:11:e16307.
doi: 10.7717/peerj.16307. eCollection 2023.

Naringenin attenuates inflammation and apoptosis of osteoarthritic chondrocytes via the TLR4/TRAF6/NF-κB pathway

Yan Wang #  1 , Zhengzhao Li #  2 , Bo Wang  3 , Ke Li  3 , Jiaxuan Zheng  4
Affiliations

Naringenin attenuates inflammation and apoptosis of osteoarthritic chondrocytes via the TLR4/TRAF6/NF-κB pathway

Yan Wang et al. PeerJ. .

Abstract

Naringenin is a flavonoid extracted from the seed coat of Anacardiaceae plants. Increasing evidence indicates that it has several properties of biological significance, such as anti-infection, sterilization, anti-allergy, antioxidant free radical, and anti-tumor. However, its effect on osteoarthritis has not been elucidated properly. In this study, the treatment of primary chondrocytes with interleukin (IL)-1β was found to increase the secretions of IL-6, tumor necrosis factor (TNF)-α, and cyclooxygenase-2 (COX-2). Further, the mRNA expression of matrix metalloproteinase ((MMP)3, MMP9, and MMP13), the protein expression of Recombinant A Disintegrin And Metalloproteinase With Thrombospondin 5 (ADAMTS5), and cell apoptosis increased; the protein expression of Collagen II decreased. The injury of primary chondrocytes induced by IL-1β was reversed under the intervention of naringenin; this reversal was dose-dependent. The mechanistic study showed that naringenin inhibited the toll-like receptor 4 (TLR4)/TNF receptor-associated factor 6 (TRAF6)/NF-κB pathway in IL-1β-stimulated primary cells, and LPS, a TLR4 activator, reversed this inhibitory effect. In addition, a mouse model of osteoarthritis was established and treated with naringenin. The results revealed that naringenin alleviated the pathological symptoms of osteoarthritis in mice, reduced the expression of TLR4 and TRAF6, and the phosphorylation of NF-κB in knee cartilage tissue. It also inhibited the secretion of inflammatory factors, reduced extracellular matrix degradation, and decreased the protein expression of cleaved caspase3. In conclusion, the findings of this study suggest that naringenin may be a potential option for the treatment of osteoarthritis.

Keywords: Chondrocytes; Inflammation; Naringenin; Osteoarthritic; The TLR4/TRAF6/NF-κB pathway.

PubMed Disclaimer

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Figure 1
Figure 1. Effect of naringenin on the viability of IL-1β-treated primary chondrocytes.
(A) The chemical structure (4′,5,7-Trihydroxyflavanone, C15H12O5) of naringenin. (B) Cell toxic effect. (C) Cell viability. N = 6. *p < 0.01 compared with Control group. #p < 0.01 compared with IL-1β group. $p < 0.01 compared with IL-1β +10 μM Naringin group. &p < 0.01 compared with IL-1β +20 μM Naringin group.
Figure 2
Figure 2. Effect of naringenin on the inflammatory response of IL-1β-treated primary chondrocytes.
The primary chondrocytes were treated with IL-1β alone or together with naringin (10, 20 and 30 μM). (A–C) The IL-6, TNF-α and COX-2 secretion levels. N = 6. *p < 0.01 compared with Control group. #p < 0.01 compared with IL-1β group. $p < 0.01 compared with IL-1β +10 μM Naringin group. &p < 0.01 compared with IL-1β +20 μM Naringin group.
Figure 3
Figure 3. Effect of naringenin on matrix degradation in IL-1β-treated primary chondrocytes.
The primary chondrocytes were treated with IL-1β alone or together with naringin (10, 20 and 30 μM). (A–C) The protein expression of MMP3, MMP9 and MMP13 was detected by Western blotting. (D–F) The Collagen II and ADAMTS5 protein expression. N = 6. *p < 0.01 compared with Control group. #p < 0.01 compared with IL-1β group. $p < 0.01 compared with IL-1β +10 μM Naringin group. &p < 0.01 compared with IL-1β +20 μM Naringin group.
Figure 4
Figure 4. Effect of naringenin on apoptosis in IL-1β-treated primary chondrocytes.
The primary chondrocytes were treated with IL-1β alone or together with naringin (10, 20 and 30 μM). (A) Cell apoptosis. (B) The protein expression of cleaved caspase3 was detected by Western blotting. N = 6. *p < 0.01 compared with Control group. #p < 0.01 compared with IL-1β group. $p < 0.01 compared with IL-1β +10 μM Naringin group. &p < 0.01 compared with IL-1β +20 μM Naringin group.
Figure 5
Figure 5. Naringenin regulates IL-1β-treated primary chondrocytes via TLR4 signaling pathway.
The IL-1β-treated primary chondrocytes were treated with naringenin alone or simultaneously intervened with TLR4 activators (LPS). (A and B) The protein expression of TLR4, TRAF6 and total NF-κB, and the phosphorylation level of NF-κB was detected by Western blotting. (C) Cell viability. (D–G) The secretion levels of IL-6, COX-2, MMP13 and Collagen II. (H) Cell apoptosis. N = 6. *p < 0.01 compared with Control group. #p < 0.01 compared with IL-1β group. $p < 0.01 compared with IL-1β + 30 μM Naringin group.
Figure 6
Figure 6. Therapeutic effects of naringenin on osteoarthritis in mice.
Sham group (the medial meniscotibial ligament was visualized but not transected), osteoarthritis group (the model was constructed by the destabilization of the medial meniscus method) and naringenin group (treated with 10 mg/kg naringin by intraperitoneal injection). (A) Representative images of HE staining of mouse knee joint cartilage tissues. (B) The protein expression of TLR4, TRAF6, total NF-κB and cleaved caspase3, and the phosphorylation level of NF-κB was detected by western blotting. (C and D) IL-6, COX-2, MMP13 and Collagen II secretion levels. (E) OARSI scores of mice. (B and F) The cleaved caspase3 expression. N = 8. *p < 0.01 compared with Sham group. #p < 0.01 compared with OA group.
See this image and copyright information in PMC

References

    1. Allen KD, Thoma LM, Golightly YM. Epidemiology of osteoarthritis. Osteoarthritis and Cartilage. 2022;30(2):184–195. doi: 10.1016/j.joca.2021.04.020. - DOI - PMC - PubMed
    1. Bai H, Zhang Z, Li Y, Song X, Ma T, Liu C, Liu L, Yuan R, Wang X, Gao L. L-Theanine reduced the development of knee osteoarthritis in rats via its anti-inflammation and anti-matrix degradation actions: in vivo and in vitro study. Nutrients. 2020;12(7):1988. doi: 10.3390/nu12071988. - DOI - PMC - PubMed
    1. Chen T, Zhou R, Chen Y, Fu W, Wei X, Ma G, Hu W, Lu C. Curcumin ameliorates IL-1β-induced apoptosis by activating autophagy and inhibiting the NF-κB signaling pathway in rat primary articular chondrocytes. Cell Biology International. 2021;45(5):976–988. doi: 10.1002/cbin.11541. - DOI - PubMed
    1. Chtourou Y, Fetoui H, Jemai R, Slima ABen, Makni M, Gdoura R. Naringenin reduces cholesterol-induced hepatic inflammation in rats by modulating matrix metalloproteinases-2, 9 via inhibition of nuclear factor κB pathway. European Journal of Pharmacology. 2015;746(34):96–105. doi: 10.1016/j.ejphar.2014.10.027. - DOI - PubMed
    1. Chu J, Yan B, Zhang J, Peng L, Ao X, Zheng Z, Jiang T, Zhang Z. Casticin attenuates osteoarthritis-related cartilage degeneration by inhibiting the ROS-mediated NF-κB signaling pathway in vitro and in vivo. Inflammation. 2020;43(3):810–820. doi: 10.1007/s10753-019-01167-y. - DOI - PubMed

LinkOut - more resources