Dr. Frank Frisch
Osteoporosis affects one in four post-menopausal women, and approximately one in three of those women will experience a fracture due to osteoporosis in their lifetime. Sleep deprivation may be a contributing factor in the acceleration of osteoporosis due to the increase in pro-inflammatory cytokine production which may potentiate the diminished estrogen signaling.
Tumor-necrosis factor alpha-type (TNFα), a pro-inflammatory cytokine of interest, stimulates osteoprotegerin ligand (OPGL) to increase the degradation of bone. Bisphosphonates, like Zolendronate, are the most commonly prescribed treatment for osteoporosis because they decrease osteoclastic activity. This study analyzed the effects of chronic sleep deprivation and Zolendronate on TNFα concentration and relative bone strength of thirty-two ovariectomized Wistar rats in a five-week protocol; groups included control (C), sleep deprived (SD), sleep deprived with Zolendronate (SDZ), and Zolendronate (Z). TNFα concentrations were determined by enzyme-linked immunoassay and bone strength was determined by a three-point bending test. The calculated TNFα concentration values for the groups were: C (M=23.97 pg/mL, 𝜎=1.87 pg/mL), SD (M=25.56 pg/mL, 𝜎=2.56 pg/mL), SDZ (M=24.02 pg/mL, 𝜎=2.17 pg/mL), and Z (M=27.26 pg/mL, 𝜎=2.22 pg/mL). The calculated bone strength values for the groups followed: C (M=161.42 N, 𝜎=19.37 N), SD (M=162.21 N, 𝜎=24.29 N), SDZ (M=165.97 N, 𝜎=22.61 N), and Z (M=156.44 N, 𝜎=20.46 N). There were significant differences (p < .01) in serum concentration of TNFα in the group taking Zolendronate, but we found no differences in bone strength between the groups – but the trends suggest that in larger sample sizes, differences would emerge. We believe that further research measuring the changes in cytokine concentration throughout a longer sleep deprivation protocol would be a fruitful.
Barrett, Noah; James, Cameron; Tam, Joshua; Ellsworth, Nicole; Curry, Dwight; and Frisch, Frank, "The Effects of Chronic Sleep Deprivation on Tumor Necrosis Factor Alpha and Bone Strength in Menopausal Rats" (2018). Student Scholar Symposium Abstracts and Posters. 295.