The Role of Gut Microbiota in an Ischemic Stroke

Abstract

The intestinal microbiome, the largest reservoir of microorganisms in the human body, plays an important role in neurological development and aging as well as in brain disorders such as an ischemic stroke. Increasing knowledge about mediators and triggered pathways has contributed to a better understanding of the interaction between the gut-brain axis and the brain-gut axis. Intestinal bacteria produce neuroactive compounds and can modulate neuronal function, which affects behavior after an ischemic stroke. In addition, intestinal microorganisms affect host metabolism and immune status, which in turn affects the neuronal network in the ischemic brain. Here we discuss the latest results of animal and human research on two-way communication along the gut-brain axis in an ischemic stroke. Moreover, several reports have revealed the impact of an ischemic stroke on gut dysfunction and intestinal dysbiosis, highlighting the delicate play between the brain, intestines and microbiome after this acute brain injury. Despite our growing knowledge of intestinal microflora in shaping brain health, host metabolism, the immune system and disease progression, its therapeutic options in an ischemic stroke have not yet been fully utilized. This review shows the role of the gut microflora-brain axis in an ischemic stroke and assesses the potential role of intestinal microflora in the onset, progression and recovery post-stroke.

Post-Ischemic Brain Neurodegeneration in the Form of Alzheimer’s Disease Proteinopathy: Possible Therapeutic Role of Curcumin

“…This suggests that the gut microflora may control curcumin metabolism and bioavailability in the body. The gut microbiome changes throughout life [141] and progressive aging is associated with reduced microbial diversity in composition, quantity and quality, and the occurrence of cerebral ischemia [13,[142][143][144][145]. There are experimental indications that curcumin may modulate the composition of the gut microbes, including microbial diversity [86,[146][147][148][149].…”

“…It is now well known that post-ischemic brain neurodegeneration is caused by a set of genetic and proteomic changes that lead to neuronal death in an amyloid-and tau protein-dependent manner, with progressive inflammation resulting in brain atrophy with the development of full-blown Alzheimer's disease dementia [4,10,11]. Research indicates that after ischemia the brain can develop the typical neurodegeneration of Alzheimer's disease [3,4,[11][12][13][14][15][16][17][18][19][20][21][22]. First, post-ischemic brain damage causes selective neuronal death in the hippocampus typical of Alzheimer's disease with progressive brain atrophy [23][24][25][26][27][28].…”

Gastrointestinal Microbiome and Neurologic Injury

“…As it relates to therapeutic modalities targeted at manipulating the gastrointestinal microbiome, the administration of probiotics has arguably shown the most promise to date as an adjunct in symptomatic alleviation of several neurologic disease processes [ 90 , 91 , 92 ]. It is also the only relevant emerging intervention whose efficacy in neurologic injury patients has been evaluated in the clinical setting with human participants [ 93 , 94 ].…”

From organ injury to disability: a proposed model for 5-alpha reductase inhibitor syndrome

“…19 A review has identified "two-way communication" between the gut and brain in ischemic stroke. 121 In summary, 5ARI-mediated changes in the neuroendocrine system, microbiome and epigenome could conceivably be downstream consequences of microvasculopathy or ischemia-reperfusion injury (Figure 11).…”