Livestock Science 128 (2010) 75–81 Contents lists available at ScienceDirect Livestock Science journal homepage: www.elsevier.com/locate/livsci Traditional Chinese medicine decoction enhances growth performance and intestinal glucose absorption in heat stressed pigs by up-regulating the expressions of SGLT1 and GLUT2 mRNA Xiaozhen Song a,b,d,1, Jianqin Xu c,2, Tian Wang a,⁎,4, Fenghua Liu d,e,3,4 a College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China b College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang 330045, PR China c College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China d College of Animal Science and Technology, Beijing University of Agriculture, Beijing 102206, PR China e Beijing Metropolis Key Laboratory of Veterinary Medicine (Traditional Chinese Medicine), Beijing University of Agriculture,Beijing 102206, PR China article info abstract Article history: This study was conducted to investigate the effects of high temperature stressor on porcine growth Received 22 April 2008 performance, small intestinal absorption and SGLT1 and GLUT2 mRNA expressions, and probe the Received in revised form 4 November 2009 regulation of traditional Chinese medicine decoction (CMD) on them. Forty-eight 2-month-old Accepted 4 November 2009 Chinese experimental pigs were screened according to weight and litter origin, and then allotted to three groups and treated as follows: normal temperature Control group (Control; 23 °C), high Keywords: temperature stressor group (HS; 26 °C for 19 h, 40 °C for 5 h); Chinese medicine decoction anti- Chinese medicine decoction stressgroup(CMD;26°Cfor19h,40°Cfor5h)(n=16 per group). Porcine average dairy feed High temperature stress Pig intake (ADFI), average dairy gain (ADG) and feed:gain ratio (F:G) were examined, and their SGLT1 intestinal disaccharidase activity and xylose absorption were investigated on days 1, 3, 6 and 10 of GLUT2 trial. A method of real-time PCR was applied to determine SGLT1 and GLUT2 mRNA expressions in the small intestine. The results showed that high temperature treatment decreased (pb0.05) the growth performance and intestinal glucose absorption but there was no change (pN0.05) in the expressions of SGLT1 and GLUT2 genes in the small intestine compared with the Control. Dietary supplementation with CMD improved porcine growth performance (pb0.05), as well as increased total disaccharidase activity and xylose absorption in the small intestine of heat stressed pigs on days 3and6(pb0.05). CMD treatment up-regulated SGLT1 andGLUT2mRNAexpressionsofpigsonday6 compared to the HS and Control groups (pb0.05). These results indicated that high temperature stressor decreased porcine growth performance and intestinal absorption of pigs, and CMD treatment improved the growth performance and intestinal glucose absorption of heat stressed pigs by up-regulating SGLT1 and GLUT2 mRNA expressions in the small intestine. © 2009 Elsevier B.V. All rights reserved. 1. Introduction the number of days to market (Hyun et al., 1998). Following the global warming, high temperature environment has Environmental stressors are potential factors that con- become a major stressor that impairs the production and tribute to the lag in BW gain that can lead to an increase in health of animals. Heat stress caused a series of physiolog- ical and metabolic changes in pigs such as elevated body temperature, panting and respiratory alkalosis, and changed ⁎ Corresponding author. Tel.: +86 25 84396483. metabolic status elicited by decreased levels of plasma E-mail address: [email protected] (T. Wang). triiodothyronine (Huynh et al., 2005; Patience et al., 2005). 1 Tel.: +86 791 3813503. Previous studies showed that heat stress can negatively 2 Tel.: +86 10 62734111. 3 Tel.: +86 10 80794699. affect not only the animals' growth performance but also 4 These two authors contributed equally to this work. their immune competence and disease resistance (Morrow- 1871-1413/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.livsci.2009.11.002 76 X. Song et al. / Livestock Science 128 (2010) 75–81 Tesch et al., 1994; Collin et al., 2001; Khajavi et al., 2003; 2.2. Animals treatment Spencer et al., 2005). Small intestine in mammal is one of the central organs In this trial the animals were kept at different ambient (Whithaker et al., 1990) that is very sensitive to all stressors temperatures for a time of 10 days. Chinese experimental (Nabuurs et al., 2001; Soderholm and Perdue, 2001). Glucose minitype pigs (CEMP, Chinese Agricultural University I series) is a major source of energy for eukaryotic cells, and has aged 2 months were bought from a commercial farm in significant and varied effects on cell function. Hydrolases, Changping district of Beijing. Forty-eight barrows with an initial namely digestive enzymes of small intestinal brush-border body weight of 7.15±0.58 kg were selected and divided into membrane vesicles (BBMVs), perform the final digestive three treatment groups according to weight and litter origin as function on nutrition, and play a critical role on digestion follows: normal temperature Control group (Control) were fed and absorption (Proulx, 1991). Glucose absorption in the under normal environment with 23 °C, and high temperature small intestine depends on two types of transport mechan- stressor group (HS) and Chinese medicine decoction anti-stress isms. One is glucose transporter 2 (GLUT2), which serves as a group (CMD) were fed under high temperature environment facilitated diffusion system through lipid bilayers, and the with 40 °C from 4:00 a.m. to 9:00 a.m. and 26 °C for other times other is Na+-dependent glucose transporter 1 (SGLT1), which within one day. Pigs in the Control and HS groups were fed the mediates Na+/glucose co-transport function both in kidney basal diet (Table 1), formulated to meet the nutrient require- and intestine as a secondary active transporter (Breves et al., ments of swine and pigs in the CMD group were fed the basal 2007). The expression of glucose transport such as SGLT1 and diet supplementation with Chinese medicine decoction, its dose GLUT2 was crucial to the absorption and transport com- was 0.15 g kg BW−1 day−1. All pigs were allowed to consume petence of glucose in the small intestine (Rodriguez et al., both feed and water ad libitum. 2004). Traditional Chinese medicine has been widely used to treat 2.3. Determination of growth performance a variety of disease and conditions, and many Chinese herbal prescriptions were demonstrated to be efficacious in the Body weights and feed intakes were measured on the treatment of heat stress syndrome. Liu et al. (2002) reported beginning and end of trial. On the basis of these data, average that Chinese herbal prescriptions had satisfactory effect on dairy feed intake (ADFI), average dairy gain (ADG), and feed:gain improving the grown performance in heat stressed pigs. (F:G) ratio were calculated during 0–1day,1–3days,3–6days Chinese medicine decoction (CMD) is composed of four and 6–10 days. herbs, including Cortex Phellodendron, Rhizome Atractylodes, Agastache rugosa and Gypsum Fibrosum, According to Chinese 2.4. Sampling collected and serum index assayed medicine principles, this decoction is prescribed for animals with heat stress syndrome. The previous study in our laboratory The experimental protocol was approved by the Commit- (Wang et al., 2007; Song et al., 2008) demonstrated that the tee for Experimental Animals at Nanjing Agricultural CMD improved porcine antioxidant status and immune competence in the small intestine under high temperature Table 1 environment (40 °C). However, no investigation was done Compositions of experimental diets (as feed basis). about the effects of the CMD on small intestinal absorption of Ingredient (%) heat stressed pigs. The current study will use glucose Maize 51.8 absorption as the index to investigate the effect of high Soybean meal 13.0 temperature stressor on the growth performance and small Fish meal 6.0 intestinal nutritional absorption of pigs, and explore the Whey 6.0 regulative mechanism for CMD on growth performance of Expanded soybean 16.0 Wheat bran 3.0 heat stress pigs. Limestone 1.5 Monocalcium phosphate 1.0 2. Materials and methods Salt 0.35 Lysine–HCl 0.22 2.1. Preparation of Chinese medicine decoction (CMD) DL-methionine 0.13 Vitamin-mineral mix a 1.0 Total 100 Chinese medicine decoction was composed of Cortex Chemical composition b Phellodendron (Huangbai), Rhizome Atractylodes (Cangzhu), A. Digestive energy (MJ/kg) 13.89 rugosa (Huoxiang) and Gypsum Fibrosum (Shigao) in the dry Crude protein (%) 20.00 Calcium (%) 0.95 weight ratio of 1:1:1:0.5. All raw materials in the decoction Total phosphorus (%) 0.70 were bought from Chinese Traditional Medicine Pharmacy Available phosphorus (%) 0.49 Tong Ren Tang. The mixture of material was immersed in water L-Lys (%) 1.35 for 40 min and extracted in boiling water for 2 h and the Met+Cys (%) 0.46 aqueous extract separated by filtration (100 mesh). Then the a Vitamins and minerals were included to provide the following amounts extract was heated (50 °C) under reduced pressure to relative per kilogram of diet: 180 mg Zn; 150 mg Fe; 150 mg Cu; 50 mg Mn; 0.3 mg I; density 1 g/mL. The concentrated extract was dried and 0.3 mg Se; 0.3 mg Co; 6500 IU vitamin A; 750 IU vitamin D3; 20 IU vitamin E; 3.5 mg vitamin K ; 2.8 mg vitamin B ; 6.2 mg vitamin B ; 33 mg niacin; combined with excipient (starch) and ground into fine 3 1 2 18 mg d-pantothenic acid; 3.5 mg vitamin B6; 0.85 mg folic acid; 60ug granules. One gram of granulated product was equivalent to biotin; 35 mg vitamin B12. 1.44 g of the raw herb.