Effects of 5′-uridylic acid feeding on postprandial plasma concentrations of GH, insulin and metabolites in young calves

Abstract

Postprandial changes in plasma concentrations of GH, insulin, IGF-I, leptin and metabolites were compared between young Holstein bull calves fed with milk alone (control group) and with milk+5 -uridylic acid (UMP) (UMP group). UMP (2 g/day) was given with milk at 0830 h and 1530 h for 11 days from the 4th to the 14th day after birth. The perirenal fat weight was significantly lower in the UMP group than in the control group, but there was no significant difference in the weights of the liver, spleen and heart between the groups. Basal GH concentrations in the UMP group were slightly higher, but the postprandial increase in plasma insulin level and the area under the curve for insulin in the UMP group were significantly lower than those in the control group.There was no significant difference in IGF-I levels between the groups. In addition, the postprandial glucose concentrations were lower in the UMP group as reflected by the insulin level, and nonesterified fatty acid concentrations were not different. In the muscle (M. longissimus thoracis) sampled at 14 days of age, the triacylglycerol (TAG) content was significantly greater but glycogen content was significantly lower in the UMP group than in the control group. From these results, we have concluded that feeding 5 -UMP at 2 g/day for 11 days significantly alters TAG accumulation in the body and plasma concentrations of GH and insulin in young bull calves.

Oral administration of uridylic acid increases plasma leptin, but suppresses glucose and non-esterified fatty acid concentrations in rats

“…However, the detailed mechanism of the reduced triacylglyceride accumulation in the rat liver remains to be clarified. The reduction in the liver was not found in milk-fed calves (Katoh et al, 2005).…”

“…In calves fed with milk containing UMP (2g/day, 126 mg/kg metabolic body size) (Katoh et al, 2005), the plasma NEFA concentration was not changed, although the postprandial increase in the plasma concentrations of glucose and insulin after milk ingestion were significantly smaller than in the control calves. In the present study with rats, however, the UMP ingestion significantly reduced the plasma levels of glucose and NEFA without changing the insulin level (Table 1).…”

“…In our previous paper with young calves (Katoh et al, 2005), the reduced postprandial plasma glucose level and increased triacylglyceride accumulation in the Longissimus muscle were demonstrated by the UMP feeding. In the present study, a slightly increased triacylglyceride accumulation was also demonstrated in the M. gastrocnemius of the rat (Fig.…”

“…The dose of 5′-UMP per metabolic body size (44 mg/day) was equivalent to that given to young calves, and it was shown to change the metabolic parameters efficiently (Katoh et al, 2005).…”

“…Recently, we fed neonatal calves milk containing 5′-UMP at 2g/day for 1week, and demonstrated that 5′-UMP feeding suppressed perirenal fat deposition and the postprandial increase in plasma insulin (Katoh et al, 2005). However, to our knowledge, the effect of 5′-UMP on metabolic levels has not yet been reported in non-ruminant animal species.…”