Dietary supplementation with proline confers a positive effect in both porcine circovirus-infected pregnant and non-pregnant mice

• Published in: British journal of nutrition Vol. 110; no. 8; pp. 1492 - 1499
• Main Authors: Ren, Wenkai, Wu, Miaomiao, Luo, Wei, Huang, Ruilin, Yin, Yulong, Li, Yinghui, Li, Teijun, yu, Xinglong
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 28.10.2013
• Subjects: Abortion, Spontaneous; Amino acids; Animal diseases; Animals; Biological and medical sciences; C-Reactive Protein - metabolism; Circoviridae Infections - immunology; Circoviridae Infections - prevention & control; Circovirus; Cytokines - blood; Dietary Supplements; Dietary Surveys and Nutritional Epidemiology; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Immune response; Immune system; Lesions; Lymphocytes; Mice; Nutrition; Polymerase Chain Reaction; Pregnancy; Pregnancy Complications, Infectious - immunology; Pregnancy Complications, Infectious - virology; Pregnancy, Animal; Proline - therapeutic use; Random Allocation; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Viral Load; Proline; Porcine circovirus type 2; Nutritional regulations; Functional amino acids; Porcine circovirus-associated diseases; Nutrition; Rodentia; Feeding; Pig; Pregnancy; Infection; Vertebrata; Regulation(control); Mammalia; Mouse; Proline: Nutritional regulations; Aminoacid; Animal; Artiodactyla; Supplementation; Ungulata
• ISSN: 0007-1145; 1475-2662
• DOI: 10.1017/S0007114513000652

Porcine circovirus type 2 (PCV2) is associated with various diseases that impose a significant economic burden on the swine industry. We hypothesised that nutritional supplementation with proline to enhance the immune response might be a useful prophylactic measure against PCV2 infection. To test this hypothesis, in the present study, we measured clinical data, including blood parameters, serum cytokine profile, PCV2 virus load in organs and serum, and microscopic lesions in the lung, liver and spleen, in both PCV2-infected pregnant and non-pregnant mice. Dietary supplementation with proline had no effect (P>0·05) on abortion rates in PCV2-infected pregnant mice, although a numerically lower abortion rate (22·2 v. 44·4 %) was observed compared with the control. Dietary supplementation with proline significantly increased serum C-reactive protein levels (P= 0·03) in PCV2-infected pregnant mice, and increased serum TNF-α levels (P= 0·01), leucocytes (P< 0·05), lymphocytes (P< 0·05) and neutrophilic granulocytes (P< 0·05) in PCV2-infected non-pregnant mice. Meanwhile, dietary proline significantly (P< 0·05) decreased the PCV2 virus load in the lung. Furthermore, mice in the dietary proline group showed a significant (P< 0·01) decrease in microscopic lesion scores in the lung, liver and spleen compared with those in the alanine group. Collectively, dietary proline supplementation confers a functional role in PCV2-infected mice.