Early programming of adult blood pressure in the low birth weight Yucatan miniature pig is exacerbated by a post-weaning high-salt-fat-sugar diet

Abstract

We previously demonstrated that intra-uterine growth-restricted (IUGR) Yucatan miniature pigs develop modestly elevated blood pressure (BP) as young adults. The present study evaluated the effects of a post-weaning Western-style, high-salt-fat-sugar (HSFS) diet on early programming of BP. IUGR piglets (3 d old, 0·77 (sem0·04) kg,n6) were paired with normal weight (NW) same-sex littermates (1·14 (sem0·03) kg,n6) and fed milk replacer for 4 weeks. A third littermate was left with the sow (SF; 1·01 (sem0·05) kg,n6). When 4 weeks old, all pigs were placed on a HSFS dietad libitumfor 5 h/d. When 11 months old, telemeters were implanted to measure BP in pigs before (4·5 % NaCl) and after (0·5 % NaCl) a 7 d reduced salt challenge. At necropsy, nephron numbers were determined. Before sexual maturity, IUGR pigs had greater relative feed intake (P < 0·05), and experienced catch-up growth with greater adiposity, with correlations between adiposity and BP (P < 0·05). Adult IUGR pigs had 26–34 % fewer nephrons and higher diastolic BP (107·7 (sem4·9) mmHg,P = 0·044) than NW (97·2 (sem1·8) mmHg) and SF (98·9 (sem5·3) mmHg) pigs. Systolic BP was similar among the three groups, but was significantly elevated compared with levels previously reported for a control diet. Salt restriction reduced BP in all groups (P < 0·05), but with no differences (P>0·05) in the degree of salt sensitivity among groups. In conclusion, a post-weaning Western-style diet exacerbates early programming of diastolic BP in Yucatan miniature swine, whereas systolic BP is more sensitive to postnatal diet.