Intra-articular injection of rebamipide prevents articular cartilage degeneration in murine post-traumatic osteoarthritis models.

Objectives: Rebamipide is a protective drug used for gastric mucosal injuries, and it also exerts protective effects for a variety of other tissues. In this study, murine post-traumatic (PT) osteoarthritis (OA) models in vivo and human OA chondrocytes in vitro were used to examine the effects of rebamipide on articular cartilage degeneration.Methods: Male BALB/c mice were used. The knee ligaments were transected in both knees. Mice were injected with rebamipide into the knee joint every week. Human chondrocytes were stimulated with IL-1ß, then treated with or without rebamipide. The levels of mRNA expression of COL2A, IL-1ß, TNFα, NF-κB, MMP3, MMP13, ADAMTS5, TIMP3, FGF2, and TGFß were estimated using real-time PCR.Results: Histological scores were significantly better in the rebamipide 1 mg/mL and 10 mg/mL groups than in the control group. Rebamipide up-regulated the mRNA expressions of COL2A, TIMP3, TGFß, and FGF2 in chondrocytes and down-regulated IL-1ß, TNFα, NF-κB, MMP3, MMP13, and ADAMTS5.Conclusion: Intra-articular injection of rebamipide prevents articular cartilage degeneration for 6 weeks in murine models of OA in vivo. Rebamipide down-regulates inflammatory cytokines and catabolic factors and up-regulates anabolic factors in human chondrocytes in vitro. Rebamipide could be an important treatment for prevention of articular cartilage degeneration.

Tenascin-C Prevents Articular Cartilage Degeneration in Murine Osteoarthritis Models.

Objective The objective of this study was to determine whether intra-articular injections of tenascin-C (TNC) could prevent cartilage damage in murine models of osteoarthritis (OA). Design Fluorescently labeled TNC was injected into knee joints and its distribution was examined at 1 day, 4 days, 1 week, 2 weeks, and 4 weeks postinjection. To investigate the effects of TNC on cartilage degeneration after surgery to knee joints, articular spaces were filled with 100 µg/mL (group I), 10 µg/mL (group II) of TNC solution, or control (group III). TNC solution of 10 µg/mL was additionally injected twice after 3 weeks (group IV) or weekly after 1 week, 2 weeks, and 3 weeks (group V). Joint tissues were histologically assessed using the Mankin score and the modified Chambers system at 2 to 8 weeks after surgery. Results Exogenous TNC was maintained in the cartilage and synovium for 1 week after administration. Histological scores in groups I and II were better than scores in group III at 4 and 6 weeks, but progressive cartilage damage was seen in all groups 8 weeks postoperatively. Sequential TNC injections (groups IV and V) showed significantly better Mankin score than single injection (group II) at 8 weeks. Conclusion TNC administered exogenously remained in the cartilage of knee joints for 1 week, and could decelerate articular cartilage degeneration in murine models of OA. We also showed that sequential administration of TNC was more effective than a single injection. TNC could be an important molecule for prevention of articular cartilage damage.

A case of early detection of bisphosphonate-related osteonecrosis of the jaw.

Osteonecrosis of the jaws is an adverse reaction associated with the use of bisphosphonates. Although the diagnosis of bisphosphonate-related osteonecrosis of the jaw (BRONJ) is based on symptomatology, it is often detected late because the patients become symptomatic only after osteonecrosis is well established. We describe a case of early oral BRONJ detected by magnetic resonance imaging (MRI) accidentally. Head MRI revealed low signal of T1-weight images in left mandibula. Patient had been treated with minodronate for osteoporosis during 18 months. Based on the MRI findings and medication history, early stage BRONJ could be considered. Therefore minodronate was switched to teriparatide. Thereafter mandible pares-thesias, odontalgia and exposed bone were not observed. This case suggests that MRI is useful for the early detection of BRONJ.

Duloxetine-induced hyponatremia in an elderly patient treated with thiazide diuretics.

Hyponatremia is a known adverse effect of duloxetine, and it can lead to potentially life-threatening complications. Administration of thiazide diuretics also has been the cause of hyponatremia. We report a case of duloxetine-induced hyponatremia in an elderly patient treated with thiazide diuretics. An 86-year-old woman treated with the trichlormethiazide was admitted for vertebral compression fracture with disorientation and nausea on the 6(th) day of treatment with duloxetine. Laboratory findings revealed hyponatremia, hypo-osmolality, concentrated urine, and increased urine sodium. Syndrome of inappropriate antidiuretic hormone was considered, therefore, duloxetine, and trichlormethiazide was discontinued and treated with fluid restriction, furosemide and sodium chloride administered orally. Disorientation and nausea were improved after correction of hyponatremia. Health care practitioners should be aware of the possibility of duloxetine-induced hyponatremia, particularly in patients treated with thiazide diuretics.