Zhang Xiaofei, Ge Xiaolei, Lu Xiaotong, Yuan Shaoyun, Ji Keke, Du Zhiyuan, Zhu Qixing, Shen Tong
Department of Occupational and Environmental Health, School of Public Health, Anhui Medical University, Hefei 230032, China.
School of Public Health, Anhui Medical University Grade 2016 Preventive Medicine, Hefei 230032, China.
Wei Sheng Yan Jiu. 2019 Nov;48(6):964-975.
To study the effect of glycogen synthase kinase 3β(GSK3β) in BPA-induced adipose tissue inflammation in high fat diet(HFD) fed mice.
Four-week-old male C57 BL/6 mice were randomly divided into normal diet(ND) group, HFD group, HFD + GSK3β inhibitor group, HFD + 1000 nmol/L BPA group, HFD+1000 nmol/L BPA+GSK3β inhibitor group. The mice were exposed to BPA via drinking water. From the 14 th week of BPA exposure to the end of 16 weeks, the GSK3β inhibitor group was intraperitoneally injected with 21. 5 mg/kg lithium chloride(Li Cl) every two days for a total of 10 times. At the end of 16 weeks, the mice were sacrificed after anesthesia, and the epididymal fat tissue was taken aseptically. The pathological changes were observed by H&E staining. The expressions of interleukin-1β(IL-1β) and tumor necrosis factor-α(TNF-α) were detected by immunohistochemistry(IHC). The expression of GSK3β protein and its S9 serine(GSK3β-S9) phosphorylation were detected by western blot.
Compared with the ND group, the body weight [(34. 97±1. 91) g]and epididymal fat pad coefficient [(3. 25±0. 39) %]of HFD group was significantly up-regulated(P < 0. 05), the adipose tissue inflammatory cell infiltration was increased, the expression of TNF-α(F = 73. 157, P < 0. 05) and IL-1β(F = 42. 788, P < 0. 05) was significantly enhanced, and the phosphorylation degree of GSK3β-S9(F = 57. 991, P < 0. 05) was decreased. The inflammatory cell infiltration of adipose tissue in the HFD+1000 nmol/L BPA group was significantly increased, the body weight [(38. 49±1. 34) g]and epididymal fat pad coefficient [(4. 41±0. 33) %] of the mice were significantly increased, the phosphorylation of GSK3β-S9(F = 57. 991, P <0. 05) was significantly down-regulated, and the expression of TNF-α(F = 73. 157, P <0. 05) and IL-1β(F = 42. 788, P <0. 05) was significantly enhanced compared with that in the HFD group. Compared with the HFD + 1000 nmol/L BPA group, the HFD + 1000 nmol/L BPA+GSK3 inhibitor group was decreased inflammatory cell infiltration in adipose tissue, significantly decreased body weight [(32. 61 ± 3. 34) g] and epididymal fat pad coefficient [(3. 33±0. 66) %], significantly increased GSK3-S9(F = 57. 991, P < 0. 05)phosphorylation, and significantly decreased TNF-α(F = 73. 157, P < 0. 05) and IL-1β(F = 42. 788, P<0. 05) expression.
GSK3β inhibitor can down-regulate BPA-induced adipose tissue inflammation, inflammatory cytokine expression and upregulate GSK3β-S9 phosphorylation in HFD-fed mice, suggesting that BPA exposure may regulate the expression of inflammatory cytokines mediating adipose tissue inflammation by affecting the degree of phosphorylation of GSK3β-S9.
研究糖原合酶激酶3β（GSK3β）在双酚A（BPA）诱导的高脂饮食（HFD）喂养小鼠脂肪组织炎症中的作用。
将4周龄雄性C57 BL/6小鼠随机分为正常饮食（ND）组、HFD组、HFD + GSK3β抑制剂组、HFD + 1000 nmol/L BPA组、HFD + 1000 nmol/L BPA + GSK3β抑制剂组。通过饮水使小鼠暴露于BPA。从BPA暴露第14周直至16周结束，GSK3β抑制剂组每两天腹腔注射21.5 mg/kg氯化锂（Li Cl），共注射10次。16周结束时，麻醉处死小鼠，无菌采集附睾脂肪组织。采用苏木精-伊红（H&E）染色观察病理变化。通过免疫组织化学（IHC）检测白细胞介素-1β（IL-1β）和肿瘤坏死因子-α（TNF-α）的表达。采用蛋白质免疫印迹法检测GSK3β蛋白及其丝氨酸9位点（GSK3β-S9）磷酸化的表达。
与ND组相比，HFD组小鼠体重[（34.97±1.91）g]和附睾脂肪垫系数[（3.25±0.39）%]显著上调（P < 0.05），脂肪组织炎性细胞浸润增加，TNF-α（F = 73.157，P < 0.05）和IL-1β（F = 42.788，P < 0.05）表达显著增强，GSK3β-S9磷酸化程度（F = 57.991，P < 0.05）降低。HFD + 1000 nmol/L BPA组小鼠脂肪组织炎性细胞浸润显著增加，体重[（38.49±1.34）g]和附睾脂肪垫系数[（4.41±0.33）%]显著增加，GSK3β-S9磷酸化（F = 57.991，P < 0.05）显著下调，与HFD组相比，TNF-α（F = 73.157，P < 0.05）和IL-1β（F = 42.788，P < 0.05）表达显著增强。与HFD + 1000 nmol/L BPA组相比，HFD + 1000 nmol/L BPA + GSK3抑制剂组小鼠脂肪组织炎性细胞浸润减少，体重[（32.61±3.34）g]和附睾脂肪垫系数[（3.33±0.66）%]显著降低，GSK3-S9磷酸化（F = 57.991，P < 0.05）显著增加，TNF-α（F = 73.157，P < 0.05）和IL-1β（F = 42.788，P < 0.05）表达显著降低。
GSK3β抑制剂可下调BPA诱导的HFD喂养小鼠脂肪组织炎症、炎性细胞因子表达，并上调GSK3β-S9磷酸化，提示BPA暴露可能通过影响GSK3β-S9磷酸化程度来调节介导脂肪组织炎症的炎性细胞因子表达。
