Therapeutic Nanodiamonds Containing Icariin Ameliorate the Progression of Osteoarthritis in Rats

Abstract

In present study, icariin (ICA)/tannic acid (TA)-nanodiamonds (NDs) were prepared as follows. ICA was anchored to ND surfaces with absorbed TA (ICA/TA-NDs) and we evaluated their in vitro anti-inflammatory effects on lipopolysaccharide (LPS)-activated macrophages and in vivo cartilage protective effects on a rat model of monosodium iodoacetate (MIA)-induced osteoarthritis (OA). The ICA/TA-NDs showed prolonged release of ICA from the NDs for up to 28 days in a sustained manner. ICA/TA-NDs inhibited the mRNA levels of pro-inflammatory elements, including matrix metalloproteinases-3 (MMP-3), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), and increased the mRNA levels of anti-inflammatory factors (i.e., IL-4 and IL-10) in LPS-activated RAW 264.7 macrophages. Animal studies exhibited that intra-articular injection of ICA/TA-NDs notably suppressed levels of IL-6, MMP-3, and TNF-α and induced level of IL-10 in serum of MIA-induced OA rat models in a dose-dependent manner. Furthermore, these noticeable anti-inflammatory effects of ICA/TA-NDs remarkably contributed to the protection of the progression of MIA-induced OA and cartilage degradation, as exhibited by micro-computed tomography (micro-CT), gross findings, and histological investigations. Accordingly, in vitro and in vivo findings suggest that the prolonged ICA delivery of ICA/TA-NDs possesses an excellent latent to improve inflammation as well as defend against cartilage disorder in OA.

Anti‐aging effects of icariin and the underlying mechanisms: A mini‐review

“…Benign prostatic hyperplasia (BPH) is a common condition in aging men that is frequently associated with troublesome lower urinary tract symptoms. 49 51,52 Second, ICA has shown the ability to suppress immune responses in several animal models. 10,11 Administrating ICA to clinical patients should be cautioned as suppression of immune responses could increase the risk for subsequent infection complications, especially for aging patients.…”

“…Although different drug delivery systems have been investigated in preclinical studies to improve the bioavailability and enhance the therapeutic efficacy of ICA, none of them is tested in clinical settings. 51 , 52 Second, ICA has shown the ability to suppress immune responses in several animal models. 10 , 11 Administrating ICA to clinical patients should be cautioned as suppression of immune responses could increase the risk for subsequent infection complications, especially for aging patients.…”