Linarin Protects against Cadmium-Induced Osteoporosis Via Reducing Oxidative Stress and Inflammation and Altering RANK/RANKL/OPG Pathway

Abstract

Cadmium (Cd) contamination in the environment is a major public health concern since it has been linked to osteoporosis and other bone deformities. Linarin is a flavonoid glycoside, and it can promote osteoblastogenesis. This research aimed to investigate the potential role of linarin against Cd-exposed bone deformations in mice model. In our research, male mice were randomly allocated into four groups: control, Cd-exposed, and Cd + linarin (20 and 40mg/kg/bw, respectively). Linarin prevented body weight loss, increased serum calcium (Ca) and phosphorus (P), and bone alkaline phosphatase (BAP) levels in Cd-exposed groups. Furthermore, linarin treatment at 20 and 40mg/kg/bw significantly decreased RANK and OPG, resulting in an increase in RANKL mRNA levels and protein distribution in the bone of Cd-exposed mice. In addition, the bone of Cd-exposed mice administered with linarin showed higher TRAP, NFATc1, MMP9, and RUNX2 mRNA levels and protein distribution. Linarin significantly decreased oxidative stress in Cd-exposed mice bone by decreasing MDA, a lipid peroxidation product. Moreover, linarin protects Cd-exposed mice antioxidant enzymes by increasing bone SOD, CAT, and GPx levels. Besides, linarin suppresses alterations in the inflammatory system, i.e., NF-κB p65/IKKβ, by reducing NF-κB p65, IKKβ, IL-6, and TNF-α in the bone of Cd-exposed animals. This study concluded that linarin has potential to cure osteoporosis in Cd-exposed mice by reducing oxidative stress and inflammation and modulating the RANK/RANKL/OPG pathway.

Keywords: Cadmium; Inflammation; Linarin; Osteoporosis; Oxidative stress; RANK/RANKL/OPG.