Adipose-Tissue-Specific Expression of Pig ApoR Protects Mice from Diet-Induced Obesity

Low Temperature Plasma Jet Treatment Promotes Skin Wound Healing by Enhancing Cell Proliferation via the PI3K-AKT and AMPK Pathways

Low temperature plasma jet (LTPJ) treatment can promote skin wound healing, but the underlying molecular mechanisms remain poorly understood. In the present study, we verified the effect of LTPJ in accelerating wound healing and investigated its underlying mechanism. With mouse model, two full-thickness dermal wounds were created in each mouse (n = 8). One wound underwent LTPJ treatment for 10 min, while the other wound without LTPJ treatment served as a control. The percentage of wound closure and collagen content in epidermis increased significantly, which indicated that LTPJ treatment significantly enhanced wound healing through contraction. RNA-seq analysis was conducted to understand the underlying mechanisms. A total of 77 differentially expressed genes (DGEs) were identified. GO and KEGG pathway enrichment analyses revealed that the DGEs were mainly related to the collagen-containing extracellular matrix, cell cycle, PI3K-AKT signalling pathway and AMPK signalling pathway, which are known to be related to wound healing. HaCaT keratinocytes were used to study LTPJ effects on cell proliferation in vitro. In agreement with the in vivo results, the in vitro datas also demonstrated that LTPJ treatment affected the activity of the PI3K-AKT and AMPK pathways. Our findings suggest that LTPJ treatment promotes skin wound healing by inducing genes associated with wound healing, promoting PI3K-AKT signalling, and suppressing the AMPK signalling pathway.

Cloning and functional verification of a porcine adipose tissue-specific promoter

Background

Fat deposition is an important economic trait in pigs. In the past decades, many genes regulating porcine fat deposition were identified by Omics technology and verified by cell biology studies. Using genetically modified pigs to investigate the function of these genes in vivo is necessary before applying in breeding. However, lack of tissue-specific promoters of pigs hinders the generation of adipose tissue-specific genetically modified pigs.

Results

In order to identify a porcine adipose tissue-specific promoter, we used the software Digital Differential Display (DDD) to screen 99 genes highly expressed in porcine adipose tissue. GO and KEGG enrichment analysis indicated that the 99 genes were mainly related to lipid metabolism. Q-PCR proved that LGALS12 was an adipose tissue-specific gene. Five truncated fragments of the LGALS12 promoter were cloned and the 4 kb fragment (L-4 kb) exhibited a high level of promoter activity in adipocytes and no promoter activity in non-adipocytes. Following co-transfection with adipogenic transcription factors, the promoter activity of L-4 kb was enhanced by PPARγ, C/EBPβ, and KLF15, whereas it was suppressed by KLF4. Finally, we demonstrated that L-4 kb can drive APOR gene expression to exert its function in adipocytes.

Conclusions

This study demonstrates that porcine LGALS12 is an adipose tissue-specific gene, and identified the 4 kb fragment of LGALS12 promoter that exhibited adipocyte-specific promoter activity. These results provide new evidence for understanding porcine fat deposition and a promoter element for adipose tissue-specific genetic modification in pigs.

Highlights

Identified porcine LGALS12 as an adipose tissue-specific gene.

Truncated LGALS12 promoter (L-4 kb) showed adipose tissue-specific promoter activity.

Identified transcription factors involved in the regulation of L-4 kb promoter activity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08627-0.

Comparative analysis of gene expression profiles in differentiated subcutaneous adipocytes between Jiaxing Black and Large White pigs

Background

Chinese domestic pig breeds are reputed for pork quality, but their low ratio of lean-to-fat carcass weight decreases production efficiency. A better understanding of the genetic regulation network of subcutaneous fat tissue is necessary for the rational selection of Chinese domestic pig breeds. In the present study, subcutaneous adipocytes were isolated from Jiaxing Black pigs a Chinese indigenous pig breed with redundant subcutaneous fat deposition and Large White pigs a lean-type pig breed with relatively low subcutaneous fat deposition. The expression profiles of mRNAs and lncRNAs were compared by RNA-seq analysis to identify biomarkers correlated with the differences of subcutaneous fat deposition between the two breeds.

Results

A total of 1058 differentially expressed genes and 221 differentially expressed lncRNAs were identified in subcutaneous adipocytes between Jiaxing Black and Large White pigs, which included 275 up-regulated mRNAs, 783 down-regulated mRNAs, 118 up-regulated lncRNAs and 103 down-regulated lncRNAs. Gene Ontology and KEGG pathway enrichment analyses revealed that the differentially expressed genes and differentially expressed lncRNAs were mainly involved in the immune response, cell fate determination, PI3K-Akt signaling pathway and MAPK signaling pathway, which are known to be related to adipogenesis and lipid metabolism. The expression levels of differentially expressed genes and differentially expressed lncRNAs according to the RNA-seq data were verified by quantitative PCR, which showed 81.8% consistency. The differences in MAPK pathway activity between Jiaxing Black and Large White pigs was confirmed by western blot analysis, which revealed elevated p38 phosphorylation in Jiaxing Black pigs.

Conclusions

This study offers a detailed characterization of mRNAs and lncRNAs in fat- and lean-type pig breeds. The activity of the MAPK signaling pathway was found to be associated with subcutaneous adipogenesis. These results provide new targets for further investigation of the molecular mechanisms regulating subcutaneous fat deposition in pigs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-020-07361-9.