The 10th International Conference on Agricultural and Biological Sciences
(ABS 2024)

Abstract: Local swine resources were widely used in modern breeding system due to its typical characteristics such as meat quality and diseases resistance however it always accompanied by some weak traits like fatty carcass and lower birth weight which result in slow growth rate and poor feed efficiency. A large number of research have shown that Excessive fat deposition is an important factor affecting placental function and leading to low birth weight in piglets. Resveratrol (RES), as a polyphenol with many positive properties, such as alleviating gestational diabetes, promoting foetal growth, and improving maternal metabolic homeostasis, has been widely studied. This study aimed to elucidate the effects of dietary 500 mg/kg RES supplementation during late pregnancy for normal (NBT) or high backfat thickness (HBT) on reproductive performance, and placental function in Shaziling sow. Results showed that resveratrol had limited effects on backfat thickness of Shaziling sow (P>0.05). HBT sow had lower total litter weight, average weight of total births, live litter weight, average weight of live births and placental efficiency (P<0.01, P<0.001, P<0.001, P<0.001, P<0.05). The supplementation of RES can significantly increase the average weight of total births, live litter weight, average weight of live births and placental efficiency (P<0.01). The average process of farrowing and stillbirth in HBT sow significantly higher than that in NBT sow (P<0.0001, P<0.01), the supplementation of RES can reduce the average process of farrowing (P=0.0773), significantly decrease the stillbirth (P<0.05). The mRNA relative expression in Shaziling sow indicated that the relative expression level of ACC mRNA related to fat synthesis in placental of HBT sow was significantly higher than that in NBT sow (P<0.05), the expression levels of LPL, HSL, and CPT-1 mRNA related to fat metabolism were significantly lower than that in NBT sow (P<0.01, P<0.05, P<0.0001). Dietary supplementary of RES can significantly increase CPT-1 mRNA expression (P<0.001). Relative expression levels of iNOS and FGF related to placental angiogenesis, SNAT1 related to animo acid transport, CD36 related to fatty acid transport were significantly lower in HBT sow (P<0.05, P<0.01, P<0.05, P<0.01). RES can significantly increase HIF-1α, VEGF-A, PlGF and FGF relative mRNA expression related to placental angiogenesis (P<0.01, P<0.05, P<0.0001, P<0.05). RES can significantly increase the relative expression levels of GLUT3 and GLUT4 mRNA related to placental glucose transport (P<0.001，P<0.05), SNAT2 and CAT-1 mRNA related to placental animo acid transport (P<0.05, P<0.01), FABPpm mRNA related to fatty acid transport (P<0.01). The fluorescence intensity of placental CD31 in HBT sow was significantly lower than that in NBT sow (P<0.01), which can be significantly increased by dietary supplementation RES (P<0.01). The fluorescence intensity of placental p-p50/p50 and p-p65/p65 in HBT sow were significantly higher than that in NBT sow (P<0.0001, P<0.0001), which related to placental inflammation status, were significantly decreased by dietary supplementation RES (P<0.001, P<0.0001). Given the significant differences between HBT and NBT sow mentioned above, and the significant regulatory effects on reproductive performance and placental function of RES on HBT sow, we further elucidated the protein expression related to angiogenesis in placenta using a high-fat mouse model. The relative protein expression of eNOS was significantly decreased under high-fat induction (P<0.001), which can significantly increase after supplementation of RES (P<0.05). And phosphorylation of PI3K, AKT, and mTOR was significantly reduced under high-fat induction (P<0.01, P<0.001, P<0.05), which can be increased by the supplementary of RES (P<0.05, P<0.05, P<0.05). The direct binding activity of RES to PI3K was measured by ex vivo pull-down assay and computational docking analysis, results showed that the binding rate of RES and PI3K reaches 70.2%, RES bound to the SH2 domain on the regulatory subunit P85 of PI3K, hydrogen bonds were formed between RES and Pro395, which can further improve the phosphorylation ability of PI3K. In conclusion, excessive backfat thickness of Shaziling sow had negative impact on reproductive performance, dietary supplementation of RES can improve reproduction performance by regulating genes expression of placental angiogenesis and nutrient transport. RES can directly bind to the PI3K protein, promote its phosphorylation, further increase the expression of downstream proteins of placental angiogenesis.
Keywords: Shaziling sow, Resveratrol, Placental function, Reproductive performance
Acknowledgements: (Optional)this study were supported by the National Natural Science Foundation of China ( U22A20515),

Biography: Dr. Jianhua He is a professor and Ph.D. supervisor of Hunan Agricultural University, and serves as PI of Animal Nutrition Basic Research Group. After awarding his Ph.D. degree in Sichuan Agricultural University in China, Dr. He completed his post-doctoral research in Kagoshima University of Japan, and has ever worked as an aid specialist in agriculture in Ethiopia. He is the expert enjoying special allowance of Hunan Provincial government, director of Feed Sub-Center of National Research Center of Engineering Technology Utilization of Botanical Functional Ingredients, director of Chinese Society of Animal Husbandry and Veterinary Medicine, and vice president of Hunan Society of Animal Husbandry and Veterinary Medicine. Dr. He focused his research on animal nutrition, and published over 100 SCI papers on the metabolism of nutriments, immunity and fat deposition, which has been cited over 2600 times, and has won first prize of Hunan Science and Technology Progress, trained more than 100 master degree students and 35 Ph.D students.