MicroRNAs (miRNAs) are important negative regulators of genes involved in physiological and pathological processes in plants and animals. It is worth exploring whether plant miRNAs play a cross-kingdom regulatory role in animals. Herein, we found that plant MIR167e-5p regulates the proliferation of enterocytes in vitro. A porcine jejunum epithelial cell line (IPEC-J2) and a human colon carcinoma cell line (Caco-2) were treated with 0, 10, 20, and 40 pmol of synthetic 2′-O-methylated plant MIR167e-5p, followed by a treatment with 20 pmol of MIR167e-5p for 0, 24, 48, and 72 h. The cells were counted, and IPEC-J2 cell viability was determined by the MTT and EdU assays at different time points. The results showed that MIR167e-5p significantly inhibited the proliferation of enterocytes in a dose- and time-dependent manner. Bioinformatics prediction and a luciferase reporter assay indicated that MIR167e-5p targets β-catenin. In IPEC-J2 and Caco-2 cells, MIR167e-5p suppressed proliferation by downregulating β-catenin mRNA and protein levels. MIR167e-5p relieved this inhibition. Similar results were achieved for the β-catenin downstream target gene c-Myc and the proliferation-associated gene PCNA. This research demonstrates that plant MIR167e-5p can inhibit enterocyte proliferation by targeting the β-catenin pathway. More importantly, plant miRNAs may be a new class of bioactive molecules for epigenetic regulation in humans and animals.

The growth hormone/insulin-like growth factor 1 (GH/IGF-1) axis has recently been recognized as an important factor related to the longevity of many organisms. MicroRNAs (miRNAs or miRs) could also participate in diverse biological processes. However, the role of miRNAs in the decline of pituitary GH during the growth process remains unclear. To better characterize the effects of miRNAs on the pituitary, we used a miRNA microarray to investigate the miRNA profile in the rat pituitary from postnatal development throughout the growth process. Then, in vitro experiments were conducted to analyze the miRNAs’ potential roles related to GH regulation. Taken together, the microarray results indicated that there were 22 miRNAs differentially expressed during pituitary development. The bioinformatics analysis suggested that the most differentially expressed miRNAs may participate in multiple pathways associated with the pituitary function. Furthermore, the in vitro findings demonstrated that miR-141-3p was involved in GH regulation.

(1) Background: As a novel type of non-coding RNA with a stable closed-loop structure, circular RNA (circRNA) can interact with microRNA (miRNA) and influence the expression of miRNA target genes. However, circRNA involved in pituitary growth hormone (GH) regulation is poorly understood. Our previous study revealed protein kinase C alpha (PRKCA) as the target gene of miR-709. Currently, the expression and function of rno_circRNA_0001004 in the rat pituitary gland is not clarified; (2) Methods: In this study, both bioinformatics analysis and dual-luciferase report assays showed a target relationship between rno_circRNA_0001004 and miR-709. Furthermore, the rno_circRNA_0001004 overexpression vector and si-circ_0001004 were constructed and transfected into GH₃ cells; (3) Results: We found that rno_circRNA_0001004 expression was positively correlated with the PRKCA gene and GH expression levels, while it was negatively correlated with miR-709. In addition, overexpression of rno-circ_0001004 also promoted proliferation and relieved the inhibition of miR-709 in GH₃ cells; (4) Conclusions: Our findings show that rno_circ_0001004 acts as a novel sponge for miR-709 to regulate GH synthesis and cell proliferation, and are the first case of discovery of the regulatory role of circRNA_0001004 in pituitary GH.

This study was to investigate the effects of dietary supplementation with putrescine on the growth performance and meat quality of chickens. A total of 480 eighty-day-old female Wenchang chickens were randomly assigned into four groups, with 8 replications per group and 15 animals per replicate. The chickens in the control group (Con) were fed a basal diet; the 3 experimental groups were fed a basal diet with 0.01%, 0.03%, and 0.05% putrescine, respectively. The experiment lasted for 40 days. The results showed that dietary supplementation with 0.05% putrescine increased (p < 0.05) the final body weight and average daily weight gain, and decreased the ratio of feed intake to the body weight gain of Wenchang chickens. Dietary supplementation with putrescine decreased the concentrations of putrescine, spermidine, and spermine in serum (p < 0.05). The contents of methionine, phenylalanine, lysine, aspartic acid, tyrosine, total essential amino acids, and total amino acids in breast muscle were higher (p < 0.05) in 0.03% and 0.05% groups than those in Con group. However, the contents of undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, arachidic acid, docosanoic acid, tricosanic acid, lignoceric acid, erucic acid, cis-11,14,17-eicosatrienoate, linoleic acid, and total n-6 monounsaturated fatty acids in breast muscle were lower (p < 0.05) in 0.03% and 0.05% groups than those in Con group. In addition, putrescine supplementation decreased (p < 0.05) the ratio of n-6/n-3 polyunsaturated fatty acids in breast meat. Overall, dietary supplementation with 0.05% putrescine enhanced the growth performance and meat quality of Wenchang chickens.

This experiment aimed to study the effects of adding Morinda officinalis polysaccharide (MOP) on the growth, carcass performance and meat quality of Wenchang chickens. A total of 480 eighty-one-day-old Wenchang chickens were randomly allocated into five groups using a completely randomized design, with eight replicates per group (n = 8 per treatment). The control group received a basal diet (CON group), while the experimental group was given a diet with 500, 1000, 2000, and 4000 mg/kg MOP supplements. During the 40 day trial, MOP supplementation did not affect the growth and carcass performance (p > 0.05), but it increased the a* value of breast muscles compared to the CON group. The breast and thigh muscles in the MOP group had significantly lower shear force than those in the CON group (p < 0.05). The MOP groups significantly decreased the muscle fibers’ cross-sectional area and diameter in the breast and thigh muscles of Wenchang chickens compared to the CON group (p < 0.05). The MOP₅₀₀ group notably raised the total number of essential amino acids and total amino acid levels in Wenchang chickens, whereas the MOP₁₀₀₀ group significantly lowered the total SFA concentration (p < 0.05). Collectively, MOP enhances Wenchang chickens’ meat quality, with optimal results at 1000 mg/kg.

Wuzhishan pigs are a typical Chinese indigenous miniature pig breed, with thin skin and high amino acid content in muscle; slow weight gain and long feeding phases limit their value. As the primary digestive and absorptive organ, the intestine is crucial for growth, yet current studies on its development are limited. This study aimed to investigate intestinal physiological differences in Wuzhishan pigs across four phases (pre-weaning: 7, 14 days; weaning: 35, 38, 45 days; fattening: 70, 100 days; maturity: 180, 240 days) by evaluating intestinal morphology, digestive enzyme activity, gut microbiota diversity via 16S rRNA gene sequencing, and metabolite characteristics via metabolomic analysis. Results showed poor intestinal morphology and enzyme activity during weaning, significant ileal and colonic microbial diversity differences across phases, increased beneficial bacteria with age, and enriched opportunistic pathogens (Streptococcus, Romboutsia, Terrisporobacter) during weaning; weaning also had lower lipid metabolites, correlated with decreased Fusobacterium, Lactobacillus, and Muribaculaceae. Fattening enhanced amino acid metabolism, with increased Lactobacillus correlated with higher amino acids and muscle-related metabolites, while maturity increased immune-related metabolites (e.g., pyridoxine) in the vitamin B6 pathway. These results explain delayed rapid weight gain in Wuzhishan pigs and provide a theoretical basis for maintaining intestinal stability and production performance.