Cadmium-Induced Bone Toxicity: Deciphering the Osteoclast-Osteoblast Crosstalk

Area of Science:

• Environmental Toxicology
• Skeletal Biology
• Mechanistic Toxicology

Background:

• Cadmium (Cd) is a widespread toxicant causing significant bone damage.
• Cd-induced bone toxicity results in osteoporosis, osteomalacia, and fractures, impacting wildlife and livestock.
• Bone remodeling, involving osteoclasts (OCs) and osteoblasts (OBs), is crucial for skeletal integrity.

Purpose of the Study:

• To review the mechanisms by which cadmium disrupts bone remodeling.
• To elucidate Cd's effects on osteoblast and osteoclast function and their communication.
• To identify potential therapeutic targets for cadmium-induced bone toxicity.

Main Methods:

• Comprehensive literature review of in vivo and in vitro studies.
• Analysis of molecular pathways affected by cadmium exposure.
• Synthesis of findings on cellular and signaling disruptions.

Main Results:

• Cadmium impairs osteoblast differentiation, mineralization, and survival via Wnt/β-catenin inhibition, oxidative stress, and apoptosis.
• Cadmium stimulates osteoclast formation and activity by upregulating RANKL/OPG, increasing ROS, and promoting inflammatory cytokines.
• Cadmium disrupts OB-OC crosstalk, leading to net bone loss.

Conclusions:

• Cadmium toxicity fundamentally disrupts bone remodeling by targeting both osteoblasts and osteoclasts.
• Epigenetic changes and altered autophagy/mitophagy may contribute to Cd-induced bone damage.
• Understanding these mechanisms is key for developing interventions and informing risk assessments.