Related Experiment Videos
A differential association of ALOX15 polymorphisms with bone mineral density in pre- and post-menopausal women
Ching-Lung Cheung1, Vivian Chan, Annie W C Kung
1Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, SAR, China.
Objective:
The 12/15-lipoxygenase gene ALOX15 is reported to be a negative regulator of BMD in knockout mice. Nonetheless results are controversial as over-expression of ALOX15 protects against inflammation-related bone loss. The aim of the present study is to systematically study the relation of ALOX15 polymorphisms in BMD variation in southern Chinese women.
Methods:
Ten tag single nucleotide polymorphisms (SNP) were genotyped in 942 subjects with either low BMD (defined by a BMD Z score < or =-1.28 at either the hip or spine) or high BMD (Z score > or =+1). Single locus and haplotype associations were performed using logistic regression with adjustment of age, height and weight.
Results:
The variant 'G' allele of rs2619112 was associated with a reduced risk of low BMD at the femoral neck in pre-menopausal women (OR = 0.442, p = 0.007) but an increased risk in post-menopausal women (OR = 1.727, p = 0.042). Haplotype analysis revealed findings similar to the single locus tests.
Conclusion:
The variant alleles of rs2619112 and rs916055 and their haplotypes of ALOX15 are associated with high BMD in pre-menopausal women but low BMD in post-menopausal women. This suggests that ALOX15 is a dual modulator of BMD variation with opposing effects in pre- and post-menopausal women.
Related Concept Videos
01:29Bone Disorders
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
01:40Bone Remodeling
01:25Role of Vitamins in Maintaining Bone Health
Vitamin A
Vitamin A is involved in the process of bone remodeling. Retinoic acid, the active metabolite of Vitamin A, has nuclear receptors in osteoblasts and osteoclasts, which are involved in bone remodeling.
Vitamin B12
Vitamin B12 acts as a cofactor during the formation of osteoblast-related proteins, such as osteocalcin. Vitamin B12 plays a role...
01:31Osteoclasts in Bone Remodeling
01:17Hormones and Bone Tissue
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
01:31Essential Minerals for Bone Health
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without...