Department of Pharmaceutical Sciences (DISFARM), Università Degli Studi di Milano, Via Mangiagalli 25, 20133, Milan, Italy.
Zambon S.p.A., Via Lillo del Duca 11, 20091, Bresso, Italy.
Redox Biol. 2024 Nov;77:103374. doi: 10.1016/j.redox.2024.103374. Epub 2024 Oct 3.
The aim of the work was to study a dose-dependent effect of inhaled carnosine (10, 50 or 100 mg/kg/day) in mice exposed to cigarette smoke as a model of chronic obstructive pulmonary disease (COPD). A dose-dependent loading of the dipeptide in lung tissue and bronchoalveolar lavage (BAL) was firstly demonstrated by LC-ESI-MS analysis. Cigarette smoke exposure induced a significant lung inflammation and oxidative stress in mice which was dose-dependently reduced by carnosine. Inflammation was firstly evaluated by measuring the cytokines content in the BAL. All the measured cytokines were found significantly higher in the smoke group in respect to control, although the data are affected by a significant variability. Carnosine was found effective only at the highest dose tested and significantly only for keratinocyte-derived cytokine (KC). Due to the high variability of cytokines, a quantitative proteomic approach to better understand the functional effect of carnosine and its molecular mechanisms was used. Proteomic data clearly indicate that smoke exposure had a great impact on lung tissue with 692 proteins differentially expressed above a threshold of 1.5-fold. Protein network analysis identified the activation of some pathways characteristic of COPD, including inflammatory response, fibrosis, induction of immune system by infiltration and migration of leukocyte pathways, altered pathway of calcium metabolism and oxidative stress. Carnosine at the tested dose of 100 mg/kg was found effective in reverting all the pathways evoked by smoke. Only a partial reverse of the dysregulated proteins was evident at low- and mid-tested doses, although, for some specific proteins, indicating an overall dose-dependent effect. Regarding the molecular mechanisms involved, we found that carnosine upregulated some key enzymes related to Nrf2 activation and in particular glutathione peroxidase, reductase, transferase, SOD, thioredoxins, and carbonyl reductase. Such mechanism would explain the antioxidant and anti-inflammatory effects of the dipeptide.
这项工作的目的是研究吸入肌肽（10、50 或 100mg/kg/天）对香烟烟雾暴露小鼠（作为慢性阻塞性肺疾病 COPD 的模型）的剂量依赖性作用。通过 LC-ESI-MS 分析，首次证明了二肽在肺组织和支气管肺泡灌洗液（BAL）中的剂量依赖性负载。香烟烟雾暴露导致小鼠肺部炎症和氧化应激显著增加，而肌肽则呈剂量依赖性降低。炎症首先通过测量 BAL 中的细胞因子含量来评估。与对照组相比，所有测量的细胞因子在吸烟组中均显著升高，尽管数据受到显著变异性的影响。只有在测试的最高剂量时，肌肽才被发现有效，并且仅对角质形成细胞衍生细胞因子（KC）有效。由于细胞因子的高度变异性，采用定量蛋白质组学方法来更好地了解肌肽的功能作用及其分子机制。蛋白质组学数据清楚地表明，烟雾暴露对肺组织有很大影响，有 692 种蛋白质的表达水平超过 1.5 倍的阈值。蛋白质网络分析确定了一些与 COPD 特征相关的途径的激活，包括炎症反应、纤维化、白细胞浸润和迁移途径引起的免疫系统诱导、钙代谢途径和氧化应激的改变。在测试剂量为 100mg/kg 的情况下，肌肽被发现可有效逆转烟雾引起的所有途径。只有在低剂量和中剂量时，才能观察到对失调蛋白的部分逆转，尽管对于一些特定的蛋白质，表明存在整体剂量依赖性效应。关于涉及的分子机制，我们发现肌肽上调了一些与 Nrf2 激活相关的关键酶，特别是谷胱甘肽过氧化物酶、还原酶、转移酶、SOD、硫氧还蛋白和羰基还原酶。这种机制可以解释二肽的抗氧化和抗炎作用。
