Publications by authors named "Meilin Hao"

6 Publications

  • Page 1 of 1

Guanidino-Acetic Acid: A Scarce Substance in Biomass That Can Regulate Postmortem Meat Glycolysis of Broilers Subjected to Pre-slaughter Transportation.

Front Bioeng Biotechnol 2020 10;8:631194. Epub 2021 Feb 10.

College of Animal Science and Technology, Jilin Agricultural University, Changchun, China.

The different substances in biomass can regulate the metabolism and reproduction of broilers. Guanidino-acetic acid (GAA) is a natural feed additive that showed a potential application in dietary for broilers, while its amount is scarce in biomass. The objective of the present study was to investigate the effects of dietary supplemented with GAA on muscle glycolysis of broilers subjected to pre-slaughter transportation. A total of 160 Qiandongnan Xiaoxiang chickens were randomly assigned into three treatments, including a basal control diet without GAA supplementation (80 birds) or supplemented with 600 mg/kg (40 birds) or 1,200 mg/kg (40 birds) GAA for 14 days. At the end of the experiment, the control group was equally divided into two groups, thus resulting in four groups. All birds in the four groups aforementioned were separately treated according to the following protocols: (1) no transport of birds of the control group fed with the basal diet; (2) a 3-h transport of birds of the control group fed with the basal diet; (3) a 3-h transport of birds fed with diets supplemented with 600 mg/kg GAA; and (4) a 3-h transport of birds fed with diets supplemented with 1,200 mg/kg GAA. The results demonstrated that 3-h pre-slaughter transport stress increased corticosterone contents and lowered glucose contents in plasma ( < 0.05), decreased pH ( < 0.05), and resulted in inferior meat quality evidenced by elevating the drip loss, cooking loss, and L value ( < 0.05). Meanwhile, 3-h pre-slaughter transport stress decreased the contents of Cr and ATP in muscle ( < 0.05) and elevated the ratio of AMP:ATP and the glycolytic potential of muscle ( < 0.05). Moreover, 3-h pre-slaughter transport resulted in a significant elevation of mRNA expressions of LKB1 and AMPKα2 ( < 0.05), as well as the increase in protein abundances of LKB1 phosphorylation and AMPKα phosphorylation ( < 0.05). However, 1,200 mg/kg GAA supplementation alleviated negative parameters in plasma, improved meat quality, and ameliorated postmortem glycolysis and energy metabolism through regulating the creatine-phosphocreatine cycle and key factors of AMPK signaling. In conclusion, dietary supplementation with 1,200 mg/kg GAA contributed to improving meat quality via ameliorating muscle energy expenditure and delaying anaerobic glycolysis of broilers subjected to the 3-h pre-slaughter transport.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fbioe.2020.631194DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7902524PMC
February 2021

Effects of dietary hydroxyproline on collagen metabolism, proline 4-hydroxylase activity, and expression of related gene in swim bladder of juvenile Nibea diacanthus.

Fish Physiol Biochem 2019 Dec 6;45(6):1779-1790. Epub 2019 Jul 6.

Guangdong Provincial Key Laboratory of Marine Biology, Shantou University, Shantou, 515063, People's Republic of China.

This study was conducted to investigate the effects of dietary hydroxyproline (Hyp) on tissue collagen level, proline 4-hydroxylase (P4H) activity as well as transcript levels of COL1As (COL1A1 and COL1A2) and P4Hαs (P4Hα(I), P4Hα(II), and P4Hα(III)) in juvenile Nibea diacanthus. A total of 450 fishes were randomized to six equal groups and fed the diet with graded supplementary Hyp-0, 5, 10, 15, 20, and 25 g kg of dry matter for 8 weeks. Results showed that fish fed diets with 10 g kg Hyp had significantly higher acid-soluble collagen (ASC) and total collagen (TC) concentrations in swim bladder than fish fed with the other diets (P < 0.05). The activity of P4H in liver and swim bladder showed a similar trend, showing first increase and then decrease with increasing dietary Hyp (P < 0.05). The mRNA expression of COL1As in swim bladder and muscle were significantly higher than those in the liver and intestines. Meanwhile, with increasing dietary Hyp, the relative expression of COL1As genes in swim bladder showed a similar pattern with the TC concentrations of swim bladder, increased significantly initially followed by a decrease. Increased dietary Hyp content corresponded with significant decrease in the mRNA level of P4Hαs in swim bladder. These results indicated that the dietary Hyp promotes the collagen accumulation of swim bladder to some extent, and the promoting action may be related to the expression of COL1As. The optimum supplement of dietary Hyp was estimated from TC of swim bladder with piecewise regression analysis to be 9.66 g kg.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10695-019-00676-9DOI Listing
December 2019

Selenium Attenuates Staphylococcus aureus Mastitis in Mice by Inhibiting the Activation of the NALP3 Inflammasome and NF-κB/MAPK Pathway.

Biol Trace Elem Res 2019 Sep 7;191(1):159-166. Epub 2018 Dec 7.

Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.

Mastitis is one of the most important diseases affecting the dairy industry in the world, and it also poses a great threat to human food safety. In this study, we explored whether selenium can inhibit the activation of the NALP3 inflammasome and NF-κB/MAPK pathway to achieve anti-inflammatory effects. Sixty BALB/c female mice were randomly divided into three groups according to diets of different selenium concentrations (high, normal, and low). After 90 days, mice fed the same selenium concentration were randomly divided into two smaller groups, one of which was inoculated with Staphylococcus aureus and the other injected with saline as a control. Through histopathologic examination staining, western blot, qPCR, and ELISA, the results showed that with increasing selenium concentrations, the expression levels of IL-1β, TNF-α, NALP3, caspase-1, and ASC were decreased in mouse mammary tissue. Therefore, this study revealed that selenium can attenuate S. aureus mastitis by inhibiting the activation of the NALP3 inflammasome and NF-κB/MAPK pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12011-018-1591-8DOI Listing
September 2019

Sterol regulatory element binding protein-1: Molecular cloning, tissue distribution and gene expression level in response to nutritional regulation in mud crab, Scylla paramamosain.

Biochem Biophys Res Commun 2018 11 3;505(3):705-711. Epub 2018 Oct 3.

Guangdong Provincial Key Laboratory of Marine Biology, Shantou University, Shantou, 515063, PR China. Electronic address:

In the present study, SREBP-1 cDNA was cloned from the hepatopancreas of mud crab (Scylla paramamosain) and characterized by performing rapid-amplification of cDNA ends. The 3361bp long full-length cDNA encodes a polypeptide with 1039 amino acids. Tissue distribution analysis revealed that SREBP-1 transcripts were widely distributed in various organs, with higher mRNA levels in the eyestalk and cranial ganglia. Further, expression level of SREBP-1 mRNA were up-regulated in proportion to the replacement of dietary fish oil (FO) with soybean oil (SO). These results may contribute to better understanding of the long-chain polyunsaturated fatty acids (LC-PUFA) biosynthetic pathway and regulation mechanism in mud crab.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbrc.2018.09.154DOI Listing
November 2018

Cloning, tissue distribution and nutritional regulation of a fatty acyl Elovl4-like elongase in mud crab, Scylla paramamosain (Estampador, 1949).

Comp Biochem Physiol B Biochem Mol Biol 2018 Mar 24;217:70-78. Epub 2017 Dec 24.

Guangdong Provincial Key Laboratory of Marine Biology, Shantou University, Shantou 515063, PR China. Electronic address:

In this report, the full-length cDNA of fatty acyl Elovl4-like elongase was cloned from the hepatopancreas of Scylla paramamosain by rapid-amplification of cDNA ends (RACE). To the best of our knowledge, this is the first report of Elovl4-like elongase in crustaceans. The full-length cDNA of Elovl4-like was 1119bp, which included a 5'-terminal untranslated region (UTR) of 58bp, a 3'-terminal UTR of 44bp and an open reading frame (ORF) of 1017bp encoding a polypeptide of 338 amino acids. Tissue distribution analysis revealed that Elovl4-like transcripts are widely distributed in various organs, with high mRNA levels in the hepatopancreas and cranial ganglia. Further, Elovl4-like transcriptional levels in hepatopancreas were up-regulated in proportion to the replacement of dietary fish oil (FO) with soybean oil (SO). The result showed that Elovl4-like transcripts increased about 0.83 and 1.12-fold respectively when SO constituted 80% and 100% of total oil (P<0.05). These results may contribute to better understanding of the long-chain polyunsaturated fatty acids (LC-PUFA) biosynthetic pathway and regulation mechanism in this species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cbpb.2017.12.010DOI Listing
March 2018

Molecular cloning, mRNA expression and nutritional regulation of a Δ6 fatty acyl desaturase-like gene of mud crab, Scylla paramamosain.

Comp Biochem Physiol B Biochem Mol Biol 2017 Jun 31;208-209:29-37. Epub 2017 Mar 31.

Guangdong Provincial Key Laboratory of Marine Biology, Shantou University, Shantou 515063, PR China. Electronic address:

Fatty acyl desaturases (Fads) are critical enzymes in the pathways for the biosynthesis of the highly unsaturated fatty acids (HUFA). Here we report on the molecular cloning, tissue expression and nutritional regulation of a Δ6 fatty acyl desaturase-like (Δ6 Fad-like) gene from mud crab, Scylla paramamosain. The full-length cDNA was 1973bp, with a 201bp of 5'-UTR, a 443bp of 3'-UTR, and an ORF of 1329bp that encoded a protein of 442 amino acids. Bioinformatics analysis showed that the deduced peptide sequence possessed the typical features of the microsomal Fads, including N-terminal cytochrome b domain containing the heme-binding motif (H-P-G-G), three histidine-rich boxes and three membrane-spanning regions. Sequence comparison revealed that the predicted protein had a high percentage identity (>53%) with Δ6 Fads from other crustacean species. The tissue distribution of mud crab Δ6 Fad-like mRNA was found predominantly in hepatopancreas, with lower expression levels in all other tissues. Quantitative real-time PCR showed that the Δ6 Fad-like transcriptional levels in hepatopancreas gradually increased with the increased replacement of dietary fish oil (FO) by soybean oil (SO). The replacement ratio of FO by SO up to 60%, 80%, and 100% were significantly up-regulated by about 2.40-fold, 2.99-fold and 3.02-fold compared with that in the control group (100% FO) respectively (P<0.05). These results may contribute to better understanding the HUFA biosynthetic pathway and regulation mechanism in this species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cbpb.2017.03.004DOI Listing
June 2017
-->