Key Laboratory of System Bio‑Medicine of Jiangxi Province, Jiujiang University, Jiujiang, Jiangxi 332000, P.R. China.
Clinical Skills Center, Affiliated Hospital of Jiujiang University, Jiujiang, Jiangxi 332000, P.R. China.
Mol Med Rep. 2019 Jun;19(6):4719-4726. doi: 10.3892/mmr.2019.10140. Epub 2019 Apr 8.
Leukemia inhibitory factor (LIF) modulates various biological processes. Although previous studies have described the effects of LIF on adipocyte differentiation, the role of LIF receptor (LIFR) on adipocyte differentiation remains unclear. Using reverse transcription‑quantitative PCR (RT‑qPCR), LIFR expression was demonstrated to increase during adipogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs), indicating that LIFR may be involved in this process. To further evaluate the association between LIFR and adipogenic differentiation, lentivirus‑mediated LIFR knockdown was performed in hMSCs. Cells were divided into two groups: Negative control group and LIFR‑knockdown group. During the adipogenic differentiation process, intracellular lipid accumulation was assessed with Oil Red O staining at various time points (days 3, 6 and 9). Additionally, the mRNA and protein expression levels of LIF, LIFR and three molecular indicators of adipogenesis, peroxisome proliferator‑activated receptor γ (PPARγ), CCAAT enhancer binding protein α (C/EBPα) and fatty acid binding protein 4 (FABP4/aP2), were assessed by RT‑qPCR and western blotting. The culture supernatant was collected to evaluate the concentration of LIF using ELISA. The present results suggested that LIFR expression progressively increased during adipogenic differentiation of hMSCs. Conversely, LIFR knockdown significantly suppressed this process. Additionally, PPARγ, C/EBPα and aP2 were inhibited following LIFR knockdown. In contrast with LIFR, the expression levels of LIF were significantly decreased after the initiation of adipogenic differentiation. Therefore, the expression levels of LIF and LIFR exhibited opposite trends. Collectively, the present results suggested that LIFR promoted adipogenic differentiation, whereas LIF may negatively regulate this process.
白血病抑制因子(LIF)调节各种生物学过程。虽然先前的研究已经描述了 LIF 对脂肪细胞分化的影响,但 LIF 受体(LIFR)在脂肪细胞分化中的作用仍不清楚。通过逆转录-定量 PCR(RT-qPCR),证明 LIFR 在人骨髓间充质干细胞(hMSC)的成脂分化过程中表达增加,表明 LIFR 可能参与这一过程。为了进一步评估 LIFR 与成脂分化的关系,在 hMSC 中采用慢病毒介导的 LIFR 敲低。将细胞分为两组:阴性对照组和 LIFR 敲低组。在成脂分化过程中,在不同时间点(第 3、6 和 9 天)用油红 O 染色评估细胞内脂质积累。此外,通过 RT-qPCR 和 Western blot 评估 LIF、LIFR 和三个脂肪生成分子标志物(过氧化物酶体增殖物激活受体 γ(PPARγ)、CCAAT 增强子结合蛋白 α(C/EBPα)和脂肪酸结合蛋白 4(FABP4/aP2)的 mRNA 和蛋白表达水平。收集培养上清液,通过 ELISA 评估 LIF 的浓度。结果表明,LIFR 的表达在 hMSC 的成脂分化过程中逐渐增加。相反,LIFR 敲低显著抑制了这一过程。此外,LIFR 敲低后 PPARγ、C/EBPα 和 aP2 受到抑制。与 LIFR 相反,在开始成脂分化后,LIF 的表达水平显著降低。因此,LIF 和 LIFR 的表达水平呈现相反的趋势。综上所述,LIFR 促进脂肪细胞分化,而 LIF 可能负调控这一过程。