Could Melatonin Modulates the Physiology of Bone Remodeling and Minerals Balance in Male Albino Rats?

Gad, Shereen B.; Mohamed, Zakaria A.; A. H., Fayed; Hafez, Mona E.; Esmail, Kariman A.

The pineal gland secretes a neuroendocrine hormone called melatonin (MEL). It has many effects, including regulation of sleep, anti-aging, antiinflammatory, and anti-oxidative activities. Melatonin helps bone regulation metabolism through promotion of alkaline phosphatase (ALP) in blood and bone tissues. The present study was designed to examine the effect of using multi light regimes on melatonin secretion and bone remodeling .Forty male albino rats (6 months old) were divided into four equal groups as follow, the 1st control (exposed to 12 hours light : 12 hours dark), The 2nd exposed to 24 hours dark, the 3rd exposed to 24 hours light and the 4th MEL treated(subcutaneously with 50 μg/100 g b.w daily for 12 weeks) exposed to 24 hours light. After 12 weeks of exposure, serum and femur samples were collected. Bones grossly examined and fixed in 10% neutral buffered formalin for histological examination and measurement of RANKL mRNA levels by real time PCR. Serum total and bone specific alkaline phosphatase (TALP and BALP respectively), corticosterone, malondialdehyde (MDA), reduced glutathione (GSH), and superoxide dismutase (SOD) activity were measured. Moreover, blood and bone minerals contentment as calcium (Ca), phosphorus (P),zinc (Zn), copper (Cu), iron ( Fe) and manganese (Mn) were determined. Results reveal a significant (P<0.01) increase in femur mass, GSH, BALP and SOD activities in the 2nd and the 4th groups. Moreover, a significant (P<0.05) increase in serum Ca level and serum & bone Zn and Fe. Moreover, there were significant (P<0.05) decrease in serum MDA and corticosterone levels in the 2nd and the 4th groups were observed and there was down regulation to RANKL mRNA in the 2nd group. In conclusion: the findings of this research may support that melatonin has a positive effect on bone building and oxidative stress in dark exposed group.

BONE remodeling; MELATONIN; PHYSIOLOGY; RNA regulation; PINEAL gland; MICRONUTRIENTS

Alexandria Journal of Veterinary Sciences, 2022, Vol 72, Issue 1, p9

1110-2047

Academic Journal

10.5455/ajvs.137780