《IJBM》（IF：8.5）|吉林农业大学：羊肚菌多糖通过抑制PANoptosis细胞死亡介导阿尔茨海默病模型神经保护作用

PANoptosis（一种整合了焦亡、凋亡和坏死性凋亡的炎症性程序性细胞死亡方式）被认为在阿尔茨海默病的发病机制中扮演重要角色，可能导致神经元功能障碍和丢失。近期，吉林农业大学的一项研究旨在分析羊肚菌多糖的结构特征，并探讨其神经保护特性及在AD病理中涉及的信号通路。研究发现，MSP的主链由→4)-α-D-吡喃葡萄糖基-(1→和→4,6)-β-D-吡喃葡萄糖基-(1→连接而成，并在→4,6)-β-D-吡喃葡萄糖基-(1→的O-4位连接有α-D-吡喃葡萄糖基-(1→作为支链。在行为学测试中，MSP能增强小鼠的记忆和认知功能，并抑制小鼠大脑中β-淀粉样蛋白的产生。进一步的蛋白质组学和代谢组学分析表明，MSP可能对PANoptosis发挥抑制作用。本研究为开发针对AD的真菌多糖多靶点治疗药物提供了概念框架。

研究背景

阿尔茨海默病是一种进行性且目前无法治愈的神经退行性疾病，最常见于老年人。AD的临床病程通常持续约10年；然而，大脑中的病理变化可能在临床症状出现前长达二十年就已开始。尽管经过一个多世纪的研究，AD的确切发病机制仍不清楚。目前对其发病机制的观点主要强调β-淀粉样蛋白聚集成斑块、以神经原纤维缠结形成为特征的tau蛋白病，以及神经炎症的慢性进展。然而，这些假说不足以完全解释AD复杂的病理生理学。PANoptosis是最近提出的一种促炎性程序性细胞死亡途径，其特征是焦亡、凋亡和坏死性凋亡之间复杂的相互作用。

羊肚菌是一种药食两用真菌，因其富含多糖、不饱和脂肪酸、维生素和其他生物活性化合物而备受重视。羊肚菌具有多种药用特性，包括免疫调节、抗疲劳和降血压作用。多糖被认为是羊肚菌中最有效的抗氧化成分，具有显著的免疫调节活性。羊肚菌多糖在体外表现出强大的DPPH自由基清除活性，表明其具有显著的抗氧化作用。此外，MSP通过激活线粒体依赖性凋亡途径抑制HepG2细胞增殖。在RAW264.7细胞中，MSP增加细胞内促炎细胞因子水平，增强细胞增殖和吞噬作用，并表现出显著的免疫调节活性。总之，这些多样的生物活性表明MSP可能具有治疗AD的潜力；然而，迄今为止，尚无研究对此进行探讨。

研究内容

本研究通过热水提取法分离MSP，随后进行纯化和结构表征。在APP/PS1小鼠中评估了其对认知能力和记忆的影响。此外，通过整合蛋白质组学和代谢组学分析，结合western blot和免疫荧光测定，阐明了MSP的神经保护机制。本研究为支持MSP作为减缓AD进展的潜在候选药物提供了实验证据。

研究结果 

Fig. 1. The purification and preliminary structural characterization of MSP. (A) MSCP-N, MSCP-1, MSCP-2 and MSCP-3 were separated via DEAE-52 anion exchange column. (B) MSCP-N was purified via HiPrep™ 26/60 Sephacryl™ S-400 column. (C) MSP-S400 was purified via Ezload 26/60 Chromdex 200 pg column. (D) The UV-VIS spectrum of MSP at the wavelength range of 200–800 nm. (E) FT-IR analysis of MSP. (F) Analysis of monosaccharide composition of standard monosaccharide mixture. (G) Analysis of monosaccharide composition of MSP. (H) Molecular weight analysis of MSP.

Fig. 2. Structural characterization of MSP using NMR. (A) 1H, (B) 13C, (C) COSY, (D) HSQC, (E) COSY-TOCSY, (F) HSQC-TOCSY, (G) NOESY, and (H) HMBC.

Fig. 3. MSP administration ameliorated memory deficits and attenuated Aβ and p-tau expression levels in APP/PS1 mice. (A) Diagram of SDT. (B) Time spent by mice on the platform. (C) Representative swim path trajectories during the place navigation test. (D) Escape latency during the place navigation test. (E) Representative swim path trajectories during the spatial probe test. (F) Number of platform crossings within a 60-s probe trial. (G) Cerebral Aβ expression levels assessed via immunohistochemistry. (H) Quantitative analysis of mean optical density of Aβ in the DG, CA1 and CA3 subregions of the hippocampus. (I) The level of Aβ40, Aβ42, APP, and p-tau in the mouse brain detected using western blot analysis. (J) The quantitative analysis of proteins depicted in (I). All protein expression levels were normalized to GAPDH, and presented as the fold of the WT mice group. n = 12 for (A) to (F), n = 4 for (G) to (J).

Fig. 4. Proteomics and metabolomics analysis in the brains of APP/PS1 mice. (A) Heat map analysis of differential proteins in the mouse brain. (B) GO analysis. (C) KEGG analysis. (D) Protein interaction map via STRING. (E) Heat map analysis of differential metabolites in the mouse brain.

Fig. 5. MSP suppresses pyroptotic activation in the brains of APP/PS1 mice. (A) NLRP3 level in the mouse brain assessed via immunofluorescence. (B) Quantitative analysis of mean fluorescence intensity of NLRP3 in the mice cortex, hippocampal DG, CA1 and CA3 regions. (C) The levels of NLRP3, IL-1β, GSDMD-N, GSDMD, cleaved-caspase 1, and caspase 1 in the mouse brain via western blot analysis. (D) The quantitative analysis of proteins depicted in (C).

Fig. 6. MSP alleviates apoptosis in the brains of APP/PS1 mice. (A) Cleaved-caspase 3 level in the mouse brain assessed via immunofluorescence. (B) The mean optical density of cleaved-caspase 3 in the mice cortex, hippocampal DG, CA1 and CA3 regions. (C) The levels of cleaved-caspase 3/8/9, caspase 3/8/9, Bcl-2 and Bax in the mouse brain via western blot analysis. (D) The quantitative analysis of proteins depicted in (C). Above proteins were normalized to the corresponding total protein or GAPDH, and presented as the fold of the WT mice group.

Fig. 7. MSP suppresses necroptotic signaling in the brains of APP/PS1 mice. (A) RIPK1 level in the mouse brain assessed via immunofluorescence. (B) Quantitative analysis of mean fluorescence intensity of RIPK1 in the mice cortex, hippocampal DG, CA1 and CA3 regions. (C) The levels of RIPK3, RIPK1, p-MLKL and MLKL in the mouse brain via western blot analysis. (D) The quantitative analysis of proteins depicted in (C). Above proteins were normalized to GAPDH, and presented as the fold of the WT mice group.

研究结论

结构表征确定MSP是一种中性葡聚糖，其主链由→4)-α-D-吡喃葡萄糖基-(1→和→4,6)-β-D-吡喃葡萄糖基-(1→连接而成。MSP通过抑制NLRP3炎症小体介导的焦亡、减弱caspase 3/8/9依赖的凋亡以及阻断RIPK1驱动的坏死性凋亡，展现出对PANoptosis的三重抑制作用。这些发现将MSP定位为一种具有相当转化潜力的先驱性PANoptosis抑制剂，尽管其在PANoptosis信号级联中的精确分子靶点仍有待阐明。本研究不仅定义了MSP的特异性抗PANoptosis活性，而且为研究真菌多糖作为神经退行性疾病的多靶点治疗药物提供了一个概念框架。

搜寻路径

英文名称：PANoptosis inhibition by Morchella sextelata polysaccharide mediates neuroprotection in Alzheimer's disease models

DOI：https://doi.org/10.1016/j.ijbiomac.2026.151128