Lactobacillus reuteri-fermented deer bone extract (LR-DBW) alleviates rheumatoid arthritis-induced osteoporosis by inhibiting osteoclastogenesis
Background
Progressive bone erosion in rheumatoid arthritis (RA) is a major driver of irreversible disability, frequently leading to osteoporosis (OP). Current disease-modifying antirheumatic drugs (DMARDs) often fall short in preventing this destructive bone remodeling. The inflammatory environment in RA disrupts crucial bone metabolism pathways. Deer bone is traditionally recognized for its bone-health benefits, but the specific therapeutic efficacy and mechanisms of its fermented products, particularly against RA-induced OP, have remained largely unexplored, representing a significant gap in natural therapeutic strategies.
Study Design
This study investigated the protective effects of Lactobacillus reuteri-fermented deer bone water extract (LR-DBW) against OP in an adjuvant arthritis (AA) rat model. Researchers first used LC-MS/MS to analyze differential peptide profiles between LR-DBW and non-fermented deer bone water extract (DBW). In vivo, the effects of LR-DBW administration on arthritis symptoms, bone mineral density (BMD), and bone microarchitecture were assessed using Micro-CT and histological staining. In vitro, the impact of LR-DBW on RANKL-induced osteoclastogenesis and actin ring formation was evaluated in RAW264.7 cells, with mechanistic insights gained via Western Blot analysis of key signaling proteins.
Results
In vivo, LR-DBW administration significantly alleviated arthritis symptoms in AA rats, demonstrating a clear therapeutic effect. The treatment also led to increased bone mineral density (BMD) and improved bone microarchitecture, indicating a direct protective action on bone health. In vitro, LR-DBW effectively inhibited RANKL-induced osteoclastogenesis in RAW264.7 cells, a critical step in preventing bone resorption. Furthermore, it suppressed actin ring formation, which is essential for osteoclast function. Mechanistically, the study found that LR-DBW inhibits the phosphorylation of ERK, JNK, and p38 proteins. > This down-regulation of ERK, JNK, and p38 phosphorylation is identified as a key mechanism by which LR-DBW alleviates osteoporosis caused by rheumatoid arthritis, primarily by inhibiting osteoclast differentiation.
Key Findings
- LR-DBW significantly alleviated arthritis symptoms in an adjuvant arthritis rat model.
- LR-DBW increased bone mineral density (BMD) and improved bone microarchitecture in AA rats.
- LR-DBW inhibited
RANKL-induced osteoclastogenesis and actin ring formation inRAW264.7cells. - LR-DBW down-regulated the phosphorylation of
ERK,JNK, andp38proteins, inhibiting osteoclast differentiation.
Why It Matters
This research highlights LR-DBW's potential as a functional food component for managing inflammatory bone diseases like RA-induced osteoporosis. For individuals seeking complementary or natural approaches to bone health, this suggests a novel, fermentation-enhanced option. While preclinical, these findings provide a mechanistic basis for deer bone's traditional uses and open avenues for developing new nutraceuticals. The identification of specific MAPK pathway inhibition (ERK, JNK, p38) offers a clearer understanding of how such natural extracts might exert their effects, potentially guiding future research into targeted interventions. Further studies are needed to translate these findings into human-applicable protocols, including optimal dosing and long-term safety.
rheumatoid-arthritis
osteoporosis
bone-health
lactobacillus-reuteri
deer-bone
osteoclastogenesis