Liver Protein Identified as Key Regulator of Male Bone Growth
A groundbreaking study conducted by McGill University, and published in Matrix Biology, has identified a liver-produced protein, plasma fibronectin, as a crucial regulator of bone growth specifically in male mice. This discovery suggests a potential biological link between liver function and male bone health, possibly explaining why men with liver disease may experience greater bone loss.
Key Findings
The research indicates that plasma fibronectin is present in higher concentrations in the blood of males compared to females. Its levels decrease when the liver is damaged, and it subsequently accumulates in bone tissue to influence bone formation. These observations suggest a greater reliance on this protein for maintaining bone strength in males.
Mari Tuulia Kaartinen, a senior author of the study and Associate Professor in McGill's Faculty of Dental Medicine and Oral Health Sciences, noted that approximately 60 percent of osteoporosis cases in men are secondary to other underlying health conditions.
The study proposes that plasma fibronectin could serve as a direct biological connection between liver disease and bone loss in men.
Research Methodology
In their laboratory experiments, researchers selectively deactivated the fibronectin gene in the liver, thereby preventing the protein's release into the bloodstream. The absence of plasma fibronectin resulted in male mice exhibiting a reduced capacity to build strong bones, while female mice remained unaffected by the genetic intervention.
Osteoporosis Context
Historically, osteoporosis has been viewed as a condition primarily driven by aging and processes within the bone, and it has been more commonly associated with women. While bone loss in women is often linked to hormonal changes during menopause, the reasons for bone loss in men, particularly after age 50, have been less understood. Osteoporosis affects at least one in three women and one in five men, leading to bone fractures during their lifetime.
Broader Implications
The findings significantly contribute to a growing understanding that osteoporosis is a systemic condition rather than one solely confined to the bone.
Kaartinen emphasized that these results illustrate how diseases can manifest differently between sexes, underscoring the importance of incorporating biological sex differences in medical research.
This approach is considered crucial for developing more precise prevention and care strategies tailored to specific biological profiles.