The long non-coding RNA lncMYOZ2 mediates an AHCY/MYOZ2 axis to promote adipogenic differentiation in porcine preadipocytes

Inhibition of AHCY impedes proliferation and differentiation of mouse and human adipocyte progenitor cells

S-adenosyl-homocysteine-hydrolase (AHCY) plays an important role in the methionine cycle regulating cellular methylation levels. AHCY has been reported to influence proliferation and differentiation processes in different cell types, e.g. in cancer cells and mouse embryonic stem cells. In the development of adipose tissue, both the proliferation and differentiation of adipocyte progenitor cells (APCs) are important processes, which in the context of obesity are often dysregulated. To assess whether AHCY might also be involved in cell proliferation and differentiation of APCs, we investigated the effect of reduced AHCY activity on human and mouse APCs in vitro. We show that the inhibition of AHCY using adenosine dialdehyde (AdOx) and the knockdown of AHCY using gene-specific siRNAs reduced APC proliferation and number. Inhibition of AHCY further reduced APC differentiation into mature adipocytes and the expression of adipogenic differentiation markers. Global DNA methylation profiling in human APCs revealed that inhibition of AHCY is associated with alterations in CpG methylation levels of genes involved in fat cell differentiation and pathways related to cellular growth. Our findings suggest that AHCY is necessary for the maintenance of APC proliferation and differentiation and inhibition of AHCY alters DNA methylation processes leading to a dysregulation of the expression of genes involved in the regulation of these processes.

lncRNA MSTRG4710 Promotes the Proliferation and Differentiation of Preadipocytes through miR-29b-3p/IGF1 Axis

Obesity, a major global health issue, is increasingly associated with the integral role of long non-coding RNA (lncRNA) in adipogenesis. Recently, we found that lncRNA-MSTRG4710 was highly expressed in the liver of rabbits fed a high-fat diet, but whether it is involved in lipid metabolism remains unclear. A series of experiments involving CCK-8, EDU, qPCR, and Oil Red O staining demonstrated that the overexpression of MSTRG4710 stimulated the proliferation and differentiation of preadipocytes while its knockdown inhibited these processes. Bioinformatics analysis showed that miR-29b-3p was a potential target gene of MSTRG4710, and IGF1 was a downstream target gene of miR-29b-3p. Luciferase reporter gene analysis and qPCR analysis confirmed that miR-29b-3p was a potential target gene of MSTRG4710, and miR-29b-3p directly targeted the 3'UTR of IGF1. The overexpression of miR-29b-3p was observed to regulate IGF1 protein and mRNA levels negatively. Additionally, a total of 414 known differentially expressed genes between the miR-29b-3p mimic, miR-29b-3p negative control (NC), siMSTRG4710, and siMSTRG4710-NC group were screened via transcriptome sequencing technology. The GO- and KEGG-enriched pathways were found to be related to lipid metabolism. The study also established that miR-29b-3p targets IGF1 to inhibit preadipocyte proliferation and differentiation. Notably, IGF1 knockdown significantly reduced preadipocyte proliferation and differentiation. Furthermore, co-transfection of pcDNA3.1(+)-MSTRG4710 and mimics into rabbit preadipocytes revealed that the mimics reversed the promotional effect of pcDNA3.1(+)-MSTRG4710. In conclusion, these results uncover that MSTRG4710 positively regulated cell proliferation and adipogenesis by the miR-29b-3p/IGF1 axis. Our findings might provide a new target for studying adipogenesis in rabbit preadipocytes and obesity.

Exosome-Mediated lncRNA LINC01140 Attenuates Breast Cancer Progression by Regulating the Wnt/β-Catenin Pathway

Exosome-delivered long non-coding RNAs have a role in the cancer control. It is unknown how exosomal LINC01140 contributes to the breast cancer (BC) growth. The purpose of this investigation is to identify exosomal LINC01140's function in the development of breast cancer. Using quantitative reverse transcripion polymerase chain reaction, the expression of LINC01140 was measured. To investigate how LINC01140 overexpression impacts BC cell proliferation, CCK-8 as well as colony formation assays (CFA) were employed. The expression of apoptosis-related proteins (Bax and Bcl-2) and Wnt/β-catenin signal pathway-related proteins (Wnt, C-myc, β-catenin, and p-GSK-3β) was assessed through Western blotting. Exosomes from BC cells were verified by western blotting to measure CD63 and CD9 levels. To examine how exosomal LINC01140 affects Wnt/β-catenin signaling pathway and xenograft tumor in nude mice, BC cell exosomes that were overexpressing LINC01140 were obtained and co-cultured with BC cells. In BC, it was discovered that LINC01140 had poor expression. BC cell proliferation was inhibited by overexpressing LINC01140, and the levels of the proteins Bcl-2, β-catenin, C-myc, and Wnt were lowered while Bax and p-GSK-3 were increased. In addition, exosomal LINC01140 hindered the activation of the Wnt/β-catenin signaling pathway, leading to a decrease in the growth of breast cancer cells in vivo. The presence of exosomal LINC01140 impedes the initiation of Wnt/β-catenin and reduces the cancerous characteristics of BC cells.