Inhibition of aging changes by lyophilized Streptococcus faecalis in diet.

Effects of dietary Streptococcus faecalis (SF) on aging were evaluated using 1-week, 6-month, and 27-month-old Wistar and SHR rats. SF was lyophilized and added to commercial pellets at 1%. SF inhibited hypertension in aging SHR. SF inhibited aging-related changes in a wide variety of tissues. These changes were a disarray of hepatic cords, portal fibrosis; calcification of cartilage matrix, dominance of chondroitin sulfate B, and keratosulfate over chondroitin sulfates A and C; aortic endothelial damage, segmental thickening, calcification, and chondroid cells in the intima; atrophy of epidermis and appendages, and increase in amorphous dermal matrix; waxy degeneration and atrophy of psoas muscles; increase in lipoperoxides in the serum, liver, and brain; and reduction of cyclic AMP and GMP in the serum. Histological changes of the xyphoid cartilage, aorta, mesenteric artery, liver, dorsal skin, and psoas muscles in 27-month-old SF rats were much less severe than those in controls.