تمايز وتفعيل مسار بانيات العظم- ناقضات العظم على فقدان العظام الناجم عن النظام الغذائي المفرط في الكوليسترول في ذكور الجرذان

Differentiation and Activation of Osteoblast-Osteoclast Pathway on Bone loss induced by Hypercholestermic Diet in Male Rats

Abstract

The aim of this study was to examine the impact of a high cholesterol diet on osteoporosis by exploring how hypercholesterolemia can enhance the differentiation and activity of osteoclasts, leading to increased bone resorption and subsequent net bone loss. The experiment was employed twentye male rats aged (1.5-2 ) months were divided as follows 2 groups : (10) rats were fed normal diet, (10) rats were fed a high cholesterol diet (2%) for 8 weeks serve as HCD group, physiological and biomarker parameters calculation RANK, RANKL, extracellular signal regulated kinase (ERK), tartrate resistance acid phosphate (TRAP), Lipid profile (TC ,TG, LDL , HDL),internal oxidant (MDA) and antioxidant (GSH), electrolytes(calcium, sodium, phosphor, potassium) ,hormones (Calcitonin, parathyroid hormone ,Vit.D) and femur bones were excised to measure of osterix gene expression, histopathological examination after the end of the experimental (8 weeks), radiological image before experimental and after 4 weeks from experimental and after the end of the experimental (8 weeks).
The results of the study showed a significant increase (P< 0.05) in the Total cholesterol (TC), Triglycerides (TG), Low density lipoprotein (LDL) in the HCD group compared to the control group. In contrast, a significant decrease (P< 0.05) in the (HDL) in the HCD group compared to the control group.
The results showed a significant increase (P< 0.05) in the serum of The receptor activator of nuclear factor Κb(RANK), the receptor activator of nuclear factor κB ligand (RANKL), extra cellular signal regulated kinase (ERK) in the HCD group compared to the control group ,while no significant change (P> 0.05) in serum Tartrate Resistance Acid Phosphate ( TRAP) levels in the HCD group compared to the control group.
The results showed a significant elevated levels (P< 0.05) of parathyroid hormone, Calcitonin, and Vitamin D in cholesterol group compared to the control group, this Study showed a significant increase (P< 0.05) in the serum of Calcium in the HCD group compared to the control group. In contrast, no a significant (P> 0.05) in the serum of Sodium, phosphors and potassium in the HCD group compared to the control group by (Na, P, K) .
Also indicated a significant decrease (P< 0.05) in GSH in HCD group compared with the control group. In contrast, a significant increase (P< 0.05) in Malnodialdehyde (MDA) observed in the HCD group compared to the control group.
On the other hand the Osterix gene showed significant up-regulation in the HCD group compared to the control group.
The histopathological examination of the bone tissue in our study showed loss of osteoblasts on borders of trabeculae, necrosis of osteocytes with multiple multinucleated osteoclasts in the HCD group compared to the normal histological section of the control group, which show normal osteocytes in lacunae , regular bone marrow cavities and regular osteoblasts in line on trabecular border.
At the end of experimental animals the study find in the cholesterol groups the study found a radiolucent area at the pelvic bones, femur bone and vertebral of rats with osteoporosis induced by a high-cholesterol diet.
In conclusion: Osterix gene enhances bone matrix mineralization by modulating the expression of genes involved and this a significant increase was associated with the concentration of calcium in serum of hypercholestermic male rats and Monitoring biomarker ERK can provide valuable information about disease progression, treatment response, and potential therapeutic targets in osteoporosis management.