The Effect of Chronic Alcohol Administration on Bone Mineral Content and Bone Strength in Male Rats

Alcohol use has been identified as a risk factor for the developmentof osteoporosis. Eight male Wistar rats at two months of age werealcoho-fed (7.6 g 95 % ethanol/kg b.w. per day) to evaluate theeffects of long-term administration (three months) of alcohol indrinking water. We have used a dose which is considered to becomparable to a dose of 1 liter of wine or 2.5 liters of 12° beerused in male adults daily. The bones were tested mechanically by athree-point bending test in a Mini Bionix (MTS) testing system. Thebones from alcohol-fed rats were characterized by a reduction inbone density as well as in ash, calcium and phosphate content. Inalcohol-fed rats the reduction in bone mineral density (10 %) wasreflected by about 12 % reduction of mechanical strength of femur(158±5.5 vs. 178±3.2 N/mm2). Alcohol significantly altered femoralcortical thickness. In our experiment alcohol itself did not exert anyantiandrogenic effect and it did not produce changes in the weightof seminal vesicles. Liver function test (GGT, ALP, AST) did notdiffer between alcohol-fed rats and control rats. Alcohol-inducedbone loss is associated with increased bone resorption anddecreased bone formation. These results document the efficacy ofalcohol at the dose of 7.6 g 95 % ethanol/kg b.w. to cause boneloss and loss of bone mechanical strength in intact rats. The resultsof the present study may be interpreted as supporting thehypothesis of alcohol as a risk factor for osteoporosis.