Dairy Microbiology Division, ICAR-National Dairy Research Institute, Karnal, India.
Department of Nutrition Biology, Central University of Haryana, Mahendergarh, India.
J Food Biochem. 2022 Jan;46(1):e14043. doi: 10.1111/jfbc.14043. Epub 2021 Dec 19.
Alzheimer's disease (AD) is the leading type of dementia in aging people and is a progressive condition that causes neurodegeneration, resulting in confusion, memory loss, and deterioration of mental functions. AD happens because of abnormal twisting of the microtubule tau protein in neurons into a tangled neurofibrillary structure. Different factors responsible for AD pathogenesis include heavy metals, aging, cardiovascular disease, and environmental and genetic factors. Market available drugs for AD have several side effects that include hepato-toxicity, accelerated cognitive decline, worsened neuropsychiatric symptoms, and triggered suicidal ideation. Therefore, an emerging alternative therapeutic approach is probiotics, which can improve AD by modulating the gut-brain axis. Probiotics modulate different neurochemical pathways by regulating the signalling pathways associated with inflammation, histone deacetylation, and microglial cell activation and maturation. In addition, probiotics-derived metabolites (i.e., short-chain fatty acid, neurotransmitters, and antioxidants) have shown ameliorative effects against AD. Probiotics also modulate gut microbiota, with a beneficial impact on neural signalling and cognitive activity, which can attenuate AD progression. Therefore, the current review describes the etiology and mechanism of AD progression as well as various treatment options with a focus on the use of probiotics. PRACTICAL APPLICATIONS: In an aging population, dementia concerns are quite prevalent globally. AD is one of the most commonly occurring cognition disorders, which is linked to diminished brain functions. Scientific evidence supports the findings that probiotics and gut microbiota can regulate/modulate brain functions, one of the finest strategies to alleviate such disorders through the gut-brain axis. Thus, gut microbiota modulation, especially through probiotic supplementation, could become an effective solution to ameliorate AD.
阿尔茨海默病（AD）是老年人中最常见的痴呆症类型，是一种进行性疾病，可导致神经退行性变，从而导致混乱、记忆丧失和精神功能恶化。AD 的发生是由于神经元中的微管 tau 蛋白异常扭曲成缠结的神经纤维结构。导致 AD 发病的不同因素包括重金属、衰老、心血管疾病以及环境和遗传因素。市场上用于 AD 的药物有几种副作用，包括肝毒性、认知能力加速下降、神经精神症状恶化和引发自杀意念。因此，一种新兴的替代治疗方法是益生菌，它可以通过调节肠脑轴来改善 AD。益生菌通过调节与炎症、组蛋白去乙酰化以及小胶质细胞激活和成熟相关的信号通路来调节不同的神经化学途径。此外，益生菌衍生的代谢物（即短链脂肪酸、神经递质和抗氧化剂）已显示出对 AD 的改善作用。益生菌还调节肠道微生物群，对神经信号和认知活动有有益影响，从而可以减轻 AD 的进展。因此，本综述描述了 AD 进展的病因和机制以及各种治疗选择，重点是使用益生菌。
在人口老龄化的情况下，全球对痴呆症的担忧非常普遍。AD 是最常见的认知障碍之一，与大脑功能下降有关。科学证据支持益生菌和肠道微生物群可以调节/调节大脑功能的发现，这是通过肠脑轴缓解此类疾病的最佳策略之一。因此，肠道微生物群的调节，特别是通过益生菌补充，可能成为改善 AD 的有效方法。
