Anorexia nervosa (AN) is an eating disorder characterized by excessive weight loss, persistent food restriction and inappropriate physical activity relative to declining energy balance. The comorbidity with depression and/or anxiety disorders might contribute to the "chronicization" of the disease. We aimed here to question first the link between physical activity and anxiety from a clinical investigation of AN patients (n = 206). Then, using a rodent model mimicking numerous physiological and metabolic alterations commonly seen in AN patients, we examined whether 1) chronic food restriction increased anxiety-like behaviour and 2) physical activity plays a role in regulating anxiety levels. To this end, we exposed young female mice to a chronic food restriction (FR, n = 8) paradigm combined or not with access to a running wheel (FRW, n = 8) for two weeks. The mice were compared to a group of mice fed ad libitum without (AL, n = 6) or with running wheel access (ALW, n = 8). We explored anxiety-like behaviour of all mice in the following tests: hyponeophagia, marble burying, elevated plus maze, open field, and the light and dark box. On the last day, we used a restraint test of 30 min duration and measured their stress reactivity by assaying plasma corticosterone. In the open field and the elevated plus-maze, we found that FRW mice behaved similarly to AL and ALW mice whereas FR mice did not express anxiety-like behaviour. The FRW mice displayed the lowest latency to reach the food in the hyponeophagia test. Regarding stress reactivity, FRW mice exhibited corticosterone reactivity after acute stress that was similar to the control mice, while FR mice did not fully return to basal corticosterone at one hour after the restraint stress. Taken together, these data demonstrate a differential reactivity to acute stress in FR conditions and a beneficial effect of running wheel activity in ALW and FRW conditions. Moreover, we report the absence of a typical anxiety-like behaviour associated with the food restriction (FR and FRW groups). We conclude that this model (FR and FRW mice) did not express typical anxiety-like behaviour, but that physical activity linked to food restriction improved coping strategies in an anxiogenic context.

中文翻译：

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与慢性食物限制相关的体育锻炼是否可以减轻雌性小鼠的焦虑，例如行为？

神经性厌食症（AN）是一种饮食失调症，其特征是体重过度下降，持续的食物限制以及相对于能量平衡下降的不适当的体育锻炼。抑郁症和/或焦虑症的合并症可能导致疾病的“慢性化”。我们的目的是首先通过对AN患者的临床研究（n = 206）来质疑身体活动与焦虑之间的联系。然后，我们使用啮齿动物模型模拟AN患者中常见的许多生理和代谢变化，我们检查了1）长期食物限制是否会增加焦虑样行为，以及2）体力活动是否在调节焦虑水平中起作用。为此，我们将雌性年轻小鼠暴露于慢性饮食限制（FR，n = 8）范式中，无论该模式是否与跑步轮（FRW，n = 8），持续两周。将小鼠与自由喂养的一组小鼠（AL，n ＝ 6）或不使用跑轮进入（ALW，n ＝ 8）进行比较。在以下测试中，我们探讨了所有小鼠的焦虑样行为：吞咽不足，大理石埋葬，高架迷宫，开阔视野以及明暗框。在最后一天，我们进行了30分钟的约束试验，并通过测定血浆皮质酮来测量其应激反应性。在开阔的田野和高架迷宫中，我们发现FRW小鼠的行为与AL和ALW小鼠相似，而FR小鼠不表达焦虑样行为。FRW小鼠在neoneophagia测试中显示到达食物的潜伏期最低。关于应激反应性，FRW小鼠在急性应激后表现出与对照小鼠相似的皮质酮反应性，而FR小鼠在束缚压力后一小时仍未完全恢复为基础皮质酮。综上所述，这些数据表明在FR条件下对急性应力的反应性不同，并且在ALW和FRW条件下，车轮运转的有益作用。此外，我们报告缺乏与食物限制相关的典型焦虑样行为（FR和FRW组）。我们得出的结论是，该模型（FR和FRW小鼠）没有表达典型的焦虑样行为，但与食物限制有关的体力活动改善了焦虑症的应对策略。我们报道缺乏与食物限制相关的典型焦虑样行为（FR和FRW组）。我们得出的结论是，该模型（FR和FRW小鼠）没有表达典型的焦虑样行为，但与食物限制有关的体力活动改善了焦虑症的应对策略。我们报道缺乏与食物限制相关的典型焦虑样行为（FR和FRW组）。我们得出的结论是，该模型（FR和FRW小鼠）没有表达典型的焦虑样行为，但与食物限制有关的体力活动改善了焦虑症的应对策略。