Characterization of reproductive hormones and related gene expression in the hypothalamus and pituitary gland in the egg-laying interval in White King pigeon.

The egg-laying interval (LI) directly reflects the laying performance of breeding pigeons, influenced by reproductive hormones. This study aimed to assess reproductive hormone levels in serum and the expression of related genes and their receptors in the hypothalamus and pituitary gland in 4 stages: first (LI1), third (LI3), fifth (LI5), and seventh (LI7) days. The results showed that serum gonadotropin-releasing hormone (GnRH) level decreased from LI1 to LI7 (P < 0.01) and peaked in LI1. The serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels stayed at high levels from LI1 to LI5. The FSH level decreased slightly from LI5 to LI7 (P > 0.05), but the LH level decreased rapidly (P < 0.01). The prolactin (PRL) levels significantly increased in LI5 (P < 0.01) compared with LI1 and then stayed at a high level. The GnRH1 expression in the hypothalamus had no significant change in LI (P > 0.05). However, the GnRHR first decreased from LI1 to LI3 (P < 0.05) and then increased. The FSH mRNA level in the pituitary gland decreased from LI1 to LI3 and slightly increased in LI5 (P > 0.05). The change pattern of FSHR was similar to that of FSH and peaked in LI5 (P < 0.05). The LH expression level was the highest in LI5 and significantly higher than that in LI3 and LI7 (P < 0.05). However, the LHR mRNA level decreased in LI (P < 0.05). The expression patterns of PRL and PRLR were similar; they were upregulated in LI and peaked in LI7 (P < 0.01). The expression pattern of GnRHR was similar to that of FSH, LH, and FSHR, suggesting the critical role of GnRHR in LI. Furthermore, the expression levels of these genes peaked in LI5, closely correlating with the maturation of the first largest follicle in pigeons. PRL-PRLR signaling inhibited GnRH activity to promote ovulation. This study provided a basis for further investigating the molecular mechanisms underlying the regulation of reproduction in pigeons.

Proteomic study on CUMS-induced senile depression mice's frontal lobe cortex and the regulating effect of KTLD formula.

OBJECTIVE: The aim of this study was to investigate the protein expression of chronic unpredictable mild stress (CUMS)-induced senile depression in SAMP-8 mice's frontal lobe cortex and the regulating effect of the kidney tonifying and liver dispersing (KTLD) formula. MATERIALS AND METHODS: A total of 15 male SAMP-8 mice were randomly divided into control, CUMS, and KTLD groups. CUMS and KTLD mice were subjected to CUMS for 21 days. Control group mice were kept to normal feeding. At the same time as molding, the herbal gavage (KTLD formula, 19.5 g/kg/d) was given from the beginning of the stress stimulation, while the control group and the CUMS group mice were given the same volume of saline for 21 days. Open-field testing (OFT) was used to assess the mice's depression levels. Isobaric tags for relative and absolute quantification (iTRAQ) were used to identify differentially expressed proteins (DEPs) in mice's frontal lobe cortex. Bioinformatics analysis including Gene Ontology (GO); Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, and protein-protein interaction (PPI) networks were utilized to study the DEPs connections. RESULTS: Results revealed that mice with senile depression experienced more anxiety and depression than control mice, whereas KTLD mice had the opposite experience. Biological processes including transport, regulation of transcription, and DNA-templated were identified in both KTLD and CUMS. The KEGG enrichment study of the DEPs in KTLD revealed their involvement in the MAPK signaling pathway, glutamatergic synapse, dopaminergic synapse, axon guidance, and ribosome. KEGG pathway enrichment showed that the mechanism of senile depression and the pathway of KTLD are closely related to axonal conductance and ribosomes. According to the PPI analysis, disease-related proteins regulated by KTLD revealed that some proteins, such as GLOI1 and TRRAP, have potential interactions. This provides fresh insight into how KTLD works to cue senile depression. CONCLUSIONS: KTLD treats senile depression via multiple targets and pathways, which may include regulations of 467 DEPs. Proteomics showed significant changes in protein levels in geriatric depression and after KTLD intervention. Senile depression involves the cross-linking and modulation of signal pathways, presenting a pattern of multiple pathways and multiple targets. According to a protein pathway enrichment and protein interaction model of KTLD in senile depression, KTLD is capable of treating senile depression via multiple pathways and targets.

Effects of alpha-lipoic acid supplementation in different stages on growth performance, antioxidant capacity and meat quality in broiler chickens.

This experiment was conducted to investigate the effect of basal dietary supplementation with 500 mg/kg alpha-lipoic acid (LA) on growth performance, antioxidant capacity and meat quality in different stages in broiler chickens. A total of 240 Arbor Acre chickens were randomly assigned into 4 treatment groups, each treatment containing 6 replicates of 10 chickens each. Group 1 was the control group without LA supplementation; Group 2 was supplied with LA in the starter period; Group 3 was supplied with LA in the grower period; and Group 4 was supplied with LA in the whole period. The results showed that LA supplementation improved average feed intake and body weight gain in all three experimental groups, especially in Group 2. LA supplementation significantly decreased abdominal fat yield in Groups 3 and 4. LA supplementation all improved hepatic total antioxidant capacity, the level of glutathione, the activities of total superoxide dismutase, catalase (CAT) and glutathione peroxidase, in particular in Group 4. LA supplementation decreased the activity of liver xanthine oxidase (XO) in all experimental groups, and that of liver monoamine oxidase in Group 3. The activities of liver CAT and XO in Group 2 were higher than that in Group 3. LA supplementation elevated the pH24 h and decreased drip loss in breast meat in Groups 3 and 4. In conclusion, LA supplementation can improve growth performance, antioxidant properties and meat quality in broiler chicken. LA supplementation in the starter period can improve growth performance and supplementation in the grower - and in the whole period can improve carcass characteristics. There was no significant difference in meat quality of broiler chickens fed on LA-supplemented diet in different stages.

Inhibition of nicotine-DNA adduct formation in mice by six dietary constituents.

Nicotine [3-(1-methyl-2-pyrrolidinyl)-pyridine] is a major alkaloid in tobacco products and has proven to be a potential genotoxic compound. Many natural dietary products can suppress the DNA adduction, and hence act as inhibitors of cancer. In this study, we investigated the inhibitory effects of curcumin, garlic squeeze, grapeseed extract, tea polyphenols, vitamin C, and vitamin E on nicotine-DNA adduction in vivo using an ultrasensitive method of accelerator mass spectrometry (AMS). The results demonstrated that all the dietary constituents induced marked dose-dependent decrease in nicotine-DNA adducts as compared with the control. The reduction rate reached about 50% for all agents, except garlic squeeze (40%), even at its highest dose level. Amongst the six agents, grapeseed extract exhibited the strongest inhibition to the DNA adduct formation. Therefore, we may arrive at a point that these dietary constituents are beneficial to prevent the harmful adduct formation, and thus to block the potential carcinogenesis induced by nicotine.