Relationship between mechanical properties and pentosidine in tendon: Effects of age, diet restriction, and aminoguanidine in broiler breeder hens

Nonenzymatic glycosylation contributes to the formation of crosslinks, whic h leads to the structural and functional deterioration of tissue protein. T he accumulation of these crosslinks in tissue proteins has been implicated in the alteration of biomechanical properties of connective tissues. The ob jective of this study was to determine whether tendon breaking time (TBT) a nd tendon breaking strength (TBS) of the flexor perforans et perforatus dig iti iii tendon were related to concentrations of pentosidine in tendons (P- t) of broiler breeder hens from 8 to 125 wk of age. In addition, effects of diet restriction (DR) and a crosslinking inhibitor, aminoguanidine (AG) on P-t, TBS, and TBT were determined. Female chicks (n = 450) were randomly a ssigned to four treatment groups immediately after hatch: ad libitum-fed (A L); diet-restricted (DR; 60% of AL); and AL and DR groups supplemented with 1.35 mg/kg BW per day AG in the feed (AL+AG and DR+AG, respectively). In A L hens, Pt increased with increasing age (P less than or equal to 0.0001). Concurrently, an age-related parallel increase was found for TBS (P less th an or equal to 0.0001) and TBT (P less than or equal to 0.0001). Rate of P- t accumulation was lower in DR (P less than or equal to 0.001), TBS (P less than or equal to 0.01), and TBT (P less than or equal to 0.02) hens compar ed with AL hens. Concentration of P, in the AL + AG group was lower (P less than or equal to 0.0002) than in the AL group; TBS and TBT (P less than or equal to 0.01) followed a similar pattern. Supplementation of DR with AG d id not affect P-t, TBS, or TBT. The age-related increase in P-t, and loss o f elasticity in the tendon was retarded by diet restriction and AG.