Lentiviral vector-mediated shRNAs targeting a functional isoform of the leptin receptor (Ob-Rb) inhibit cartilage degeneration in a rat model of osteoarthritis.

To downregulate the expression of leptin receptor functional isoform (Ob-Rb) on chondrocytes using lentiviral vector-mediated short-hairpin RNA (LV-shRNA) and to determine its effects on cartilage degeneration. In vitro, quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were performed to select an optimal Ob-Rb LV-shRNA (LV-shRNA3) and to determine its effects on nine OA-related mediators in cultured rat chondrocytes. In vivo, an OA model was surgically induced in the right knees of rats, and LV-shRNA3, lentiviral vector-mediated non-targeting control sequence (LV-NTC) or phosphate buffered saline was injected into the joints. Osteoarthritis Research Society International (OARSI) scoring was performed to assess cartilage degeneration, and immunohistochemistry was performed to evaluate OA-related mediator expression in the above groups. Ob-Rb expression was significantly downregulated by LV-shRNA3 in cultured chondrocytes. In conjunction with Ob-Rb downregulation, the expression levels of pro-inflammatory mediators (TNF-α, IL-1β and IL-6) and catabolic mediators (ADAMTS-5, MMP-9, NOS-2 and COX-2) were also significantly decreased, and the expression levels of anabolic type II collagen were significantly increased. The in vivo study results showed that OARSI scores were significantly decreased by LV-shRNA3. Immunohistochemistry analysis demonstrated that Ob-Rb expression levels on chondrocytes were significantly downregulated by LV-shRNA3. In conjunction with Ob-Rb downregulation, ADAMTS-5 and MMP-9 expression levels were also significantly decreased, and type II collagen expression levels were increased. These results indicate that LV-shRNA3-mediated Ob-Rb downregulation on chondrocytes inhibits cartilage degeneration in a rat model of OA, suggesting that Ob-Rb may be a novel target in the treatment of OA.

Deng SL ，Zhu J ，Huang Q ，Fu WL ，Li Q ，Chen G ，Tang X ，Li J ... -  《-》

Protective effect of lentivirus-mediated siRNA targeting ADAMTS-5 on cartilage degradation in a rat model of osteoarthritis.

Chu X ，You H ，Yuan X ，Zhao W ，Li W ，Guo X ... -  《-》

Differential expression of leptin and leptin's receptor isoform (Ob-Rb) mRNA between advanced and minimally affected osteoarthritic cartilage; effect on cartilage metabolism.

Simopoulou T ，Malizos KN ，Iliopoulos D ，Stefanou N ，Papatheodorou L ，Ioannou M ，Tsezou A ... -  《OSTEOARTHRITIS AND CARTILAGE》

Alpha-Mangostin protects rat articular chondrocytes against IL-1β-induced inflammation and slows the progression of osteoarthritis in a rat model.

Osteoarthritis (OA) is a joint disease characterized by inflammation and cartilage degradation. α-Mangostin (α-MG), which can be isolated from the fruit of the tropical evergreen tree Garcinia mangostana-L, is known to have anti-inflammatory properties. The aim of the study was to investigate the use of α-MG in the treatment of OA, using both rat chondrocytes and an OA rat model induced by destabilization of the medial meniscus (DMM). Rat chondrocytes were pretreated with α-MG (0, 1.25, 2.5, and 5.0μg/ml for 24h) prior to stimulation with interleukin-1β (IL-1β) (10ng/ml for 24h). Nitric oxide (NO) production was determined using the Griess method and prostaglandin E2 (PGE2) was assessed using an enzyme-linked immunosorbent assay (ELISA). The expression of inducible nitric oxide synthase (INOS), cyclooxygenase-2 (COX-2), matrix metalloproteinase-3, -9, and -13 (MMP-3, MMP-9, and MMP-13), Collagen II, and Aggrecan were detected by both quantitative real-time PCR (qRT-PCR) and a western blot analysis. Nuclear factor-κB (NF-κB) signaling molecules were detected by western blot analysis. Detection of p65 nuclear translocation of NF-κB was examined using immunofluorescence staining. The OA rats received intraperitoneal injections of α-MG (10mg/kg) or saline every other day. Hematoxylin and eosin and Safranin-O-Fast green staining were used to evaluate the severity of cartilage lesions up to 8weeks following surgery. α-MG inhibited the production of NO and PGE2. The elevated expression of INOS, COX-2, MMP-3, MMP-9, and MMP-13, and the degradation of Collagen II and Aggrecan, were reversed by α-MG in IL-1β-stimulated chondrocytes. In addition, IL-1β induced considerable phosphorylation of the NF-kB signaling pathway, which was inhibited by α-MG. Furthermore, the immunofluorescence staining demonstrated that α-MG could suppress IL-1β-induced p65 nuclear translocation. In vivo, cartilage treated with α-MG showed attenuated degeneration and had low Osteoarthritis Research Society International (OARSI) scores compared with the control group. Taken together, these results show that α-MG has potential therapeutic value in the treatment of OA.

Pan T ，Wu D ，Cai N ，Chen R ，Shi X ，Li B ，Pan J ... -  《-》

Effects of Hesperidin on H₂O₂-Treated Chondrocytes and Cartilage in a Rat Osteoarthritis Model.

Gao G ，Ding H ，Zhuang C ，Fan W ... -  《MEDICAL SCIENCE MONITOR》