keratan-sulfate and Low-Back-Pain

A prospective experimental study.. To investigate the potential of serum keratan sulfate (KS) as an indicator of biochemical changes in intervertebral discs induced by physical loading of the back.. By providing objective information on exposure and effects at the tissue level, biomarkers may enable us to improve our understanding of the intermediate steps between exposure to physical loading and the occurrence of back disorders. Serum KS has been proposed as a potential biomarker of the molecular changes in intervertebral discs that occur because of physical loading and are a potential cause of back disorders.. Thirty-two nonimpaired men volunteers with a mean age of 22.5+/-2.3 years participated in the experimental condition, a manual lifting task, as well as in the control condition, lying on the back. Serum KS levels were measured immediately before and after both conditions, as well as 24 hours and 1 week later.. No significant changes in serum KS levels were found after exposure to physical loading (mean SD serum KS before, 287.4+/-83.9 ng/mL; immediately after, 279.5+/-65.5 ng/mL; 24 hours after, 266.6+/-71.9 ng/mL; and 1 week after, 268.9+/-79.3 ng/mL), and no significant changes were found after lying on the back for 8 hours (mean+/-SD serum KS before, 273.0+/-94.3 ng/mL; immediately after, 261.6+/-68.9 ng/mL; 24 hours after, 277.3+/-68.9 ng/mL; and 1 week after, 274.5+/-68.5 ng/mL).. These results indicate that the serum KS level is not suitable as a biomarker of the effects of short-term physical loading of the back induced by a manual lifting task.

Topics: Adult; Aggrecans; Analysis of Variance; Biomarkers; Chondroitin Sulfates; Extracellular Matrix Proteins; Humans; Keratan Sulfate; Lectins, C-Type; Lifting; Low Back Pain; Male; Prospective Studies; Proteoglycans; Rest; Stress, Mechanical; Weight-Bearing

Characterization of the analytic profile of proteoglycans in the intervertebral discs at L4-L5 of nondiabetic (n = 5) and diabetic (n = 5) age-matched subjects. The discs used were discarded material from operations.. To clarify the reason for the higher risk of disc prolapse in diabetic patients.. The pathogenesis of diabetes results from a combination of neurologic dysfunctions and a yet undefined metabolic failure, which leads to an abnormal proteoglycan profile.. The following methods were used to determine the proteoglycan profile: the measurement of 35S-sulfate uptake per gram wet tissue into sulfated glycosaminoglycan using fresh tissue explants; extraction of proteoglycans by 4 M guanidinium chloride containing protease inhibitors, with further purification by ultracentrifugation on cesium chloride buoyant density gradient under dissociative conditions; total uronic acid and protein contents in the various gradient fractions; assessing the length of sugar side chains of isolated 35Sulfate-glycosaminoglycan molecules by separation of the glycosaminoglycan molecules on a Sepharose 6B-CL column; and paper chromatography of the final digest products of glycosaminoglycan molecules obtained by chondroitinase ABC, a glycosaminoglycan-degrading enzyme.. The findings show that discs from normal nondiabetic subjects have 15 times the rate of 35Sulfate incorporation into glycosaminoglycan molecules than do discs of diabetic patients. The proteoglycans of diabetic patients are banded at a lower buoyant density, indicating a lowered glycosylation rate and a lower number of sugar side chains per core protein. In discs of diabetic patients, there is a slight increase in the chain length of chondroitin sulfate. Further analysis of the glycosaminoglycan chains showed a decreased amount of keratan sulfate, compared with that in nondiabetic subjects. However, the total uronic acid content of the disc tissues and the ratio of uronic acid to protein of each fraction were unchanged in diabetic patients versus that in control subjects.. Discs in patients with diabetes have proteoglycans with lower buoyant density and substantially undersulfated glycosaminoglycan, which with the specific neurologic damage in these patients, might lead to increased susceptibility to disc prolapse.

Topics: Aged; Chondroitin Sulfates; Chromatography, Gas; Diabetes Complications; Diabetes Mellitus; Female; Glycosaminoglycans; Humans; Intervertebral Disc; Intervertebral Disc Displacement; Keratan Sulfate; Low Back Pain; Lumbar Vertebrae; Male; Middle Aged; Proteoglycans; Uronic Acids