Changes in skeletal tissue during the aging process

Potential Osteoporosis Recovery by Deep Sea Water through Bone Regeneration in SAMP8 Mice

The aim of this study is to examine the therapeutic potential of deep sea water (DSW) on osteoporosis. Previously, we have established the ovariectomized senescence-accelerated mice (OVX-SAMP8) and demonstrated strong recovery of osteoporosis by stem cell and platelet-rich plasma (PRP). Deep sea water at hardness (HD) 1000 showed significant increase in proliferation of osteoblastic cell (MC3T3) by MTT assay. For in vivo animal study, bone mineral density (BMD) was strongly enhanced followed by the significantly increased trabecular numbers through micro-CT examination after a 4-month deep sea water treatment, and biochemistry analysis showed that serum alkaline phosphatase (ALP) activity was decreased. For stage-specific osteogenesis, bone marrow-derived stromal cells (BMSCs) were harvested and examined. Deep sea water-treated BMSCs showed stronger osteogenic differentiation such as BMP2, RUNX2, OPN, and OCN, and enhanced colony forming abilities, compared to the control group. Interestingly, most untreated OVX-SAMP8 mice died around 10 months; however, approximately 57% of DSW-treated groups lived up to 16.6 months, a life expectancy similar to the previously reported life expectancy for SAMR1 24 months. The results demonstrated the regenerative potentials of deep sea water on osteogenesis, showing that deep sea water could potentially be applied in osteoporosis therapy as a complementary and alternative medicine (CAM).

Multifactorial analysis of risk factors for reduced bone mineral density among postmenopausal women

INTRODUCTION

The study aimed to determine the risk factors for reduced bone mineral density (BMD) among postmenopausal women.

MATERIAL AND METHODS

Two hundred and fifty-three postmenopausal women were included to the study. The study group consisted of 85 women with osteoporosis (mean age: 59.9 years) and 168 with osteopenia (mean age: 57.8 years). Patients were assigned to groups according to their BMD measured in the lumbar spine, hip and femoral neck by dual X-ray absorptiometry. Bone formation was assessed by measuring serum osteocalcin and bone resorption by measuring serum C-terminal type I α-collagen chain telopeptide.

RESULTS

Multiple regression analysis for lumbar spine showed association of age (p = 0.001), parental history of fracture (p = 0.05), use of hormone replacement therapy (p = 0.034), bisphosphonates therapy (p < 0.001), calcium and vitamin D supplements therapy (p = 0.001), oestradiol level (p = 0.007) and body mass index (p < 0.001). Multiple regression analysis for femoral neck and hip total showed association of age (p = 0.001), parental history of fracture (p = 0.049), use of bisphosphonates (p < 0.03)) use of calcium and vitamin D supplements (p = 0.039), oestradiol level (p = 0.047). All the variables together explain 40.4% of variance in BMD for the lumbar spine and 25.6% of variance in BMD for femoral neck and hip total.

CONCLUSIONS

The present study demonstrated correlations between the variables and BMD, which are known and widely described in the literature. Osteoporosis and osteopenia in Polish subjects appear to be associated with several known risk factors that are well described in the literature.

Update on the pharmacogenetics of the vitamin D receptor and osteoporosis

Vitamin D and calcium are essential for normal skeletal growth and for maintaining the mechanical and structural integrity of the skeleton. Reduced intake of calcium and vitamin D may be associated with reduced bone mass and osteoporosis while a chronic and severe vitamin D deficiency may lead to osteomalacia. Given the importance of vitamin D in bone homeostasis, common polymorphisms in the vitamin D receptor gene were the first to be investigated as possible determinants of bone mass and fracture risk. Even though results are still conflicting and the molecular mechanisms by which these polymorphisms influence receptor activity remain in part to be investigated, an additional important issue is represented by their potential pharmacogenomic and pharmacogenetic implications. This review analyzes major pharmacogenetic studies of polymorphisms in the vitamin D receptor gene and osteoporosis.

Genetics of osteoporosis: role of steroid hormone receptor gene polymorphisms

Osteoporosis is a common skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fracture. In the past years, twin and family study have shown that this disease recognizes a strong genetic component and that genetic factors play an important role in regulating bone mineral density (BMD). While in few isolate conditions osteoporosis can be inherited in a simple Mendelian pattern, due to single gene mutations, in the majority of cases has to be considered a multifactorial polygenic disease in which genetic determinants are modulated by hormonal, environmental and nutritional factors. Given the important role that steroid hormones play in bone cell development and in the maintenance of normal bone architecture, polymorphisms at receptor of the steroid/thyroid hormone receptor superfamily, such as estrogen receptor alpha (ERalpha) and Vitamin D receptor (VDR) have been thoroughly investigated in the last years and appeared to represent important candidate genes. The individual contribution of these genetic polymorphisms to the pathogenesis of osteoporosis remains to be universally confirmed and an important aim in future work will be to define their functional molecular consequences and how these polymorphisms interact with each other and with the environment to cause the osteoporotic phenotype. A further promising application of genetic studies in osteoporosis comes from their pharmacogenomic implications, with the possibility to give a better guidance for therapeutic agents commonly used to treat this invalidating disorder or to identify target molecules for new therapeutic agents.

Contributions of dietary calcium and physical activity to primary prevention of osteoporosis in females

In the United States and many Western nations, increasing prevalence of osteoporotic fracture is contributing to the health care system burden, and costs and needs for medical services are predicted to increase significantly by the beginning of the 21st century. Recent reports investigating developmental changes in skeletal mass of adolescent girls and young women under different experimental or ecological conditions support the contention that modification of environmental factors, especially dietary calcium and physical activity, can favorably modulate bone mass and bone density compared to controls. The peripubertal period, starting as early as 10 years of age, seems to be most responsive to modification of environmental/lifestyle factors, whereas potential gains of bone mass during late adolescence and early adulthood, although smaller, may be more readily achieved through improved dietary calcium intakes and regular exercise programs. Scientific evidence in support of these beneficial effects on bone is presented as part of the rationale for prevention of osteoporotic fractures. Also discussed is the need for a national policy to prevent osteoporosis through primary prevention strategies focused at young girls prior to puberty. The goal would be for every prepubertal girl, over the next decade, to achieve peak bone mass (and density) of the spine, hips and other bones by age 20, i.e., early adulthood. A second target group for national policy should be women in their 20s. Attainment of the goal to gain 3-5% additional bone mass during this decade would prolong the time before the fracture threshold range (low bone mass) is reached in the postmenopausal decades.