Lnc AK079912在小鼠脂肪组织发育及棕色化过程中的时序表达规律

Time-sequential expression of lnc AK079912 during adipose tissue development and browning in mice

目的研究新的长链非编码RNA lnc AK079912在小鼠代谢相关组织、脂肪组织发育及棕色化过程中的时序表达情况。方法采集8周龄C57BL/6J小鼠肩胛间棕色脂肪组织(iBAT)、皮下白色脂肪组织(sWAT)、附睾白色脂肪组织(eWAT)、肝脏和肌肉组织,以及发育过程中(出生第0天,第21天、第8周和第6月的小鼠)、4℃冷刺激1~5 d和腹腔注射CL316,243(1μg/g体质量)1~5 d小鼠(8~10周龄)的iBAT、sWAT和eWAT,利用Trizol提取上述组织中的总RNA,RT-qPCR技术检测lnc AK079912的表达情况;同时分离培养小鼠原代前体脂肪细胞并诱导分化至成熟,利用CL316,243(2μmol/L)诱导不同时间,提取细胞总RNA,并利用RT-qPCR技术检测lnc AK079912的表达情况。结果 lnc AK079912在小鼠脂肪组织,尤其是iBAT中高表达,肌肉次之,而在肝脏中几乎不表达(4.63±0.71 vs 1.00±0.18 vs 0;P<0.05);在脂肪组织发育过程中,iBAT和sWAT的lnc AK079912表达水平持续上升,而在eWAT中先上升后下降(P<0.001);冷刺激1~5 d lnc AK079912的表达量差异无统计学意义(P>0.05),腹腔注射CL316,243 1~5 d,lnc AK079912的表达量在iBAT和sWAT中下降(P<0.05),而在eWAT中上升(P<0.05),但在CL316,243处理24 h内的脂肪细胞中,其表达量有显著增加(P<0.05)。结论 lnc AK079912在脂肪组织中高表达;伴随着脂肪组织的发育,其表达量逐渐升高,但存在部位特异性。lnc AK079912在脂肪组织棕色化的早期有显著升高,提示lnc AK079912在脂肪组织发育及棕色化过程中起着重要的调控作用。

Objective To investigate the time-sequential expression of a novel long non-coding RNA, lnc AK079912, in metabolically related tissues and during adipose tissue development and browning in mice. Methods The interscapular brown adipose tissue(iBAT), subcutaneous white adipose tissue(sWAT), epididymal white adipose tissue(eWAT), liver tissues and muscular tissues were collected from 8-week-old C57 BL/6 J mice. The i BAT, sWAT and eWAT were also collected from the mice during development(0 day, 21 days, 8 weeks and 6 months after birth) and from 8-to 10-week-mice with cold exposure(4℃)and intraperitoneal injections of CL316,243(1 μg/g body weight) for 1 to 5 days. Trizol was used to extract the total RNA from the tissues, and RT-qPCR was performed to detect the expressions of lnc AK079912. Isolated mouse preadipocytes in primary culture were induced for adipogenic differentiation for 9 days and then treated with CL316,243(2 μmol/L) for different durations(no longer than 24 h);the expression of lnc AK079912 in the cells was detected using RT-qPCR at different time points of the treatment. Results Lnc AK079912 was highly expressed in mouse adipose tissues, the highest in iBAT, followed by the muscular tissue, but was hardly detected in the liver tissue. The expression level of lnc AK079912 increased progressively in iBAT and s WAT during development of the mice, while its expression in eWAT showed an initial increase followed by a reduction at 8 weeks(P<0.001). No significant difference was found in the expression of lnc AK079912 in the iBAT, sWAT or eWAT in mice with cold stimulation for 1 to 5 days(P>0.05). The expression of lnc AK079912 was significantly decreased in iBAT and eWAT(P<0.05) but increased in eWAT from mice with intraperitoneal injection of CL316,243 for 1 to 5 days(P<0.05). The expression level in the adipocytes in primary culture was significantly increased in response to treatment with CL316,243(P<0.05). Conclusion Lnc AK079912 is highly expressed in mouse adipose tissue, and its expression gradually increases with the development of adipose tissue but with a depot-specific difference. Lnc AK079912 is significantly elevated in the early stage of adipose tissue browning, indicating its important role in the development and browning of adipose tissue.