Effect of dietary restriction on manganese-induced neurotoxicity in mice
-
摘要:
目的 探讨饮食限制在锰诱导神经毒作用损伤过程中的作用及机制。 方法 40只成年昆明小鼠雌雄各半,随机分为4组:对照组、饮食限制组、锰暴露组和饮食限制锰暴露组。每周测量体重、观察行为学改变、检测血糖值,取小鼠脑组织计算脑脏器系数、检测脑内锰蓄积量、分析脑内炎症因子水平并检测相关蛋白表达。 结果 与对照组比较,锰暴露组小鼠行为学发生异常改变,脑系数下降,白细胞介素4(IL-4)下降,肿瘤坏死因子 – α(TNF-α)和诱导型一氧化氮合酶(iNOS)、核因子 – κB(NF-κB)、caspase-8升高(P < 0.05),引起炎症反应;与锰暴露组比较,饮食限制锰暴露组小鼠脑脏器系数下降、TNF-α、iNOS含量下降,NF-κB、caspase-8表达水平降低(P < 0.05)。 结论 饮食限制在锰诱导神经毒作用损伤中具有一定的保护作用;其机制可能与其抑制炎症反应、降低凋亡水平、增强自噬作用有关。 Abstract:Objective To explore the effect and mechanism of dietary restriction (DR) on manganese (Mn)-induced neurotoxicity. Methods Forty adult Kunming mice (male : female = 1 : 1) were randomly divided into four groups (10 in each group): control group (25.0 g feed/day and intraperitoneal injection of saline), DR control group (12.5 g feed/day and intraperitoneal injection of saline), Mn exposure group (25.0 g feed/day and intraperitoneal injection of Mn at dose of 200 μmol/kg) and DR intervention group (12.5 g feed/day and intraperitoneal injection of Mn at dose of 200 μmol/kg). The treatments were conducted once a day continuously for 6 weeks. The mice′s weight and blood glucose were measured and their behavioral changes were observed every week. By the end of the treatments, the brain specimens were collected for determinations of brain coefficient, cumulated Mn content, levels of inflammatory factors, and expressions of related proteins. Results In the Mn exposed mice, abnormal behavioral changes were observed; decreased brain coefficient and interleukin 4 (IL-4) but increased tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), protein expression of nuclear factor kappa B (NF-κB), and caspase-8 were detected compared to those in the control mice (all P < 0.05). Decreased brain coefficient, TNF-α, iNOS, NF-κB, and caspase-8 were detected in the Mn exposed mice with DR in comparison with those in the Mn exposed mice with normal feeding (P < 0.05 for all). Conclusion Dietary restriction could play a protective role in Mn-induced neurotoxicity and the effect may be related to inflammation suppression, apoptosis reduction, and autophagy enhancement in mice. -
Key words:
- dietary restriction /
- manganese /
- neurotoxicity /
- inflammation /
- apoptosis /
- autophagy
1) (高亮为本文并列第一作者) -
表 1 锰暴露对小鼠行为学影响(n = 6,
$\bar x \pm s$ )组别 爬杆时间(s) 疲劳转棒时间(s) 总移动距离(m) 活跃度 平均移动速度(mm/s) 对照组 11.77 ± 2.33 135 ± 23.26 19.15 ± 2.48 51.86 ± 8.86 63.85 ± 8.28 饮食限制组 11.57 ± 2.29 136.17 ± 21.02 18.83 ± 3.03 53.92 ± 748 66.93 ± 9.32 锰暴露组 24.33 ± 3.66 a 35.83 ± 7.94 a 3.15 ± 0.91 a 12.95 ± 2.51 a 13.18 ± 3.76 a 饮食限制锰暴露组 23.31 ± 3.70 b 34.67 ± 7.53 b 3.49 ± 0.78 b 13.86 ± 1.64 b 12.51 ± 3.26 b 注:与对照组比较,a P < 0.05;与饮食限制组比较,b P < 0.05。 表 2 饮食限制与染锰对小鼠脑系数、脑内锰含量、血糖值影响(n = 6,
$\bar x \pm s$ )组别 体重(g) 脑重(g) 脑系数(%) 脑锰含量(µg/g) 血糖值(mmol/L) 对照组 32.60 ± 2.13 0.37 ± 0.02 1.14 ± 0.09 0.14 ± 0.02 7.9 ± 0.7 饮食限制组 25.21 ± 1.06 0.29 ± 0.02 1.15 ± 0.08 0.13 ± 0.01 7.7 ± 0.8 锰暴露组 34.57 ± 2.14 0.32 ± 0.02 0.93 ± 0.08 a 0.41 ± 0.03 a 7.3 ± 1.4 饮食限制锰暴露组 26.85 ± 1.69 0.28 ± 0.01 1.05 ± 0.07 bc 0.43 ± 0.06 b 7.5 ± 0.7 注:与对照组比较,a P < 0.05;与饮食限制组比较,b P < 0.05;与染锰组比较,c P < 0.05。 表 3 饮食限制对锰暴露小鼠脑内炎症因子水平影响(n = 4,
$\bar x \pm s$ )组别 IL-4(pg/mL) TNF-α(pg/mL) iNOS(ng/mL) 对照组 142.96 ± 12.47 675.55 ± 16.01 19.05 ± 0.64 饮食限制组 145.44 ± 9.36 665.00 ± 19.44 18.89 ± 0.56 锰暴露组 96.83 ± 4.58 a 870.87 ± 14.62 a 24.21 ± 0.37 a 饮食限制锰暴露组 112.00 ± 8.00 bc 761.75 ± 22.93 bc 20.86 ± 1.21 bc 注:与对照组比较,a P < 0.05;与饮食限制组比较,b P < 0.05;与锰暴露组比较,c P < 0.05。 表 4 饮食限制对锰暴露小鼠脑内相关蛋白表达水平影响(n = 4,
$\bar x \pm s$ )组别 caspase-8 cleaved caspase-8 NF-κB p-NF-κB LC3-II/LC3-I 对照组 1.00 ± 0.02 0.66 ± 0.05 0.77 ± 0.17 0.52 ± 0.07 0.66 ± 0.06 饮食限制组 1.01 ± 0.06 0.69 ± 0.07 0.8 ± 0.16 0.53 ± 0.08 0.66 ± 0.11 锰暴露组 1.71 ± 0.25 a 1.31 ± 0.21 a 1.64 ± 0.19 a 1.12 ± 0.10 a 1.13 ± 0.08 a 饮食限制锰暴露组 1.37 ± 0.20 bc 0.90 ± 0.09 bc 1.36 ± 0.29 b 0.87 ± 0.11 bc 1.60 ± 0.17 bc 注:与对照组比较,a P < 0.05;与饮食限制组比较,b P < 0.05;与锰暴露组比较,c P < 0.05。 -
[1] 褚光辉, 宋美慧, 周正, 等. 啮齿类动物饮食限制的研究进展[J]. 生理科学进展, 2020, 51(5): 395 – 400. doi: 10.3969/j.issn.0559-7765.2020.05.015 [2] Moreno CL, Mobbs CV. Epigenetic mechanisms underlying lifespan and age-related effects of dietary restriction and the ketogenic diet[J]. Molecular and Cellular Endocrinology, 2017, 455: 33 – 40. doi: 10.1016/j.mce.2016.11.013 [3] Horning KJ, Caito SW, Tipps KG, et al. Manganese is essential for neuronal health[J]. Annual Review of Nutrition, 2015, 35: 71 – 108. doi: 10.1146/annurev-nutr-071714-034419 [4] Vermeij WP, Dollé MET, Reiling E, et al. Restricted diet delays accelerated ageing and genomic stress in DNA-repair-deficient mice[J]. Nature, 2016, 537(7620): 427 – 431. doi: 10.1038/nature19329 [5] 高海涛, 邵邻相, 成文召, 等. 饮食限制对高脂小鼠体重、血脂和学习记忆的影响研究[J]. 浙江预防医学, 2013, 25(3): 1 – 4. [6] 任姗姗, 云少君, 贺晓娟, 等. 饮食热能限制对脑老化小鼠学习记忆及突触可塑性的影响[J]. 营养学报, 2011, 33(3): 318 – 320. [7] 邵邻相, 李姣, 徐玲玲, 等. 饮食限制58 d对小鼠学习记忆及抗氧化能力的影响[J]. 浙江师范大学学报: 自然科学版, 2011, 34(1): 81 – 85. [8] Tuschl K, Mills PB, Clayton PT. Manganese and the brain[J]. International Review of Neurobiology, 2013, 110: 277 – 312. [9] Yan DY, Xu B. The role of autophagy in manganese-induced neurotoxicity[J]. Frontiers in Neuroscience, 2020, 14: 574750. doi: 10.3389/fnins.2020.574750 [10] Bok E, Jo M, Lee S, et al. Dietary restriction and neuroinflam-mation: a potential mechanistic link[J]. International Journal of Molecular Sciences, 2019, 20(3): 464. doi: 10.3390/ijms20030464 [11] Brandhorst S, Harputlugil E, Mitchell JR, et al. Protective effects of short-term dietary restriction in surgical stress and chemo-therapy[J]. Ageing Research Reviews, 2017, 39: 68 – 77. doi: 10.1016/j.arr.2017.02.001 [12] Gabandé-Rodríguez E, de las Heras MMG, Mittelbrunn M. Control of inflammation by calorie restriction mimetics: on the crossroad of autophagy and mitochondria[J]. Cells, 2020, 9(1): 82 – 103. [13] Chi W, Chen HR, Li F, et al. HMGB1 promotes the activation of NLRP3 and caspase-8 inflammasomes via NF-κB pathway in acute glaucoma[J]. Journal of Neuroinflammation, 2015, 12: 137 – 148. doi: 10.1186/s12974-015-0360-2