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Advanced Neurology TMAO and stroke

people at risk of stroke. According to the current study, on the relationship between TMAO and stroke severity
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reducing red meat in the diet may theoretically reduce the discovered that higher levels of TMAO were linked to an
risk of cerebrovascular disease, but further prospective increased risk of first stroke in Chinese patients. Moreover,
evaluation is warranted. the National Institutes of Health Stroke Scale scores and
High-fat and high-protein diets promote an increase in infarct volume were positively correlated with serum
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TMAO levels, whereas resveratrol, allicin, capsaicin, and TMAO levels (r = 0.427, P < 0.001; r = 0.243; P < 0.001).
other dietary components found in apples and oolong tea TMAO is directly associated with unfavorable outcomes in
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can reduce TMAO levels. Therefore, dietary control can patients with IS, independent of traditional risk factors.
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effectively reduce the risk of IS, benefiting many people However, no significant risk association was observed
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at heightened risk for this medical condition. One study for TMAO precursors (carnitine, choline, and betaine).
found that adding probiotics to the diet or consuming Further studies and clinical trials are needed to confirm
foods fermented by lactic acid bacteria can reduce TMAO this relationship. Meanwhile, research found that greater
levels. Supplementing probiotics serves as a potentially plasma TMAO levels upon admission can be a predictor
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effective measure to control TMAO concentrations. of the severity of IS. In fact, TMAO is also linked to
Likewise, 3,3-dimethyl-1-butanol (DMB), an inhibitor of further medication therapy in cerebral infarction patients.
TMA lyase that reduces plasma TMAO levels by lowering Circulating TMAO decreases the efficacy of clopidogrel on
TMA formation, can slow down the process of increased platelet aggregation, according to research conducted in a
platelet reactivity and atherosclerosis. 52,53 A comparison rat model of ischemia-reperfusion. TMAO is also a possible
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of the effects of different application routes showed that mediator of clopidogrel resistance. In the IS treatment,
although oral DMB can significantly reduce plasma TMAO most patients are routinely treated with antiplatelet
levels, a considerable amount of DMB administered under agents. Therefore, the relationship between TMAO and
the skin failed to achieve the same effect. As a plant-based clopidogrel should be given sufficient attention, and
antitoxin commonly found as a bioactive component more research is needed to determine whether patients
of grape juice and wine, resveratrol is a non-flavonoid with high circulating TMAO levels could benefit more
polyphenol chemical molecule. It is readily absorbed from the use of non-platelet P2Y12 receptor antagonists.
when taken orally and eliminated in the urine. Through The TMAO levels have a regulatory effect on the platelet
the modification of the intestinal microbiota, resveratrol function, but their impact on platelet reactivity and
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increases the production of new liver bile acids and thrombosis has been found to be reversible. By targeting
decreases TMAO levels, hence mitigating TMAO-induced TMAO in therapeutic strategies, whether through dietary
atherosclerosis. 54 control or pharmacological intervention to regulate
circulating TMAO levels, it is possible to mitigate platelet
The application of broad-spectrum antibiotics can hyperreactivity. Compared with the current conventional
reportedly inhibit TMAO levels. However, the role of antiplatelet drugs, this type of intervention reduces
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antibacterial treatment in disease prevention has been platelet hyperreactivity to the normal range and attenuates
controversial. Even if antibiotics can suppress the spike thrombotic tendencies without increasing the incidence of
in TMAO levels, their long-term effects remain largely symptomatic bleeding. The above explanation highlights
unknown. However, a study pointed out that the long- the significant importance of in-depth research on TMAO
term use of a single antibiotic (6 months of ciprofloxacin) for the treatment of stroke patients. TMAO is not only
conferred an initial inhibitory effect on plasma TMAO related to the severity of stroke but may also affect the
levels in rodent models, but such suppressive property efficacy of commonly used antiplatelet drugs, such as
became completely deprived in the later stages. Therefore, clopidogrel. Therefore, developing personalized treatment
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the effect of antibiotics on TMAO levels still needs to plans based on patients’ TMAO levels and selecting the
be further studied. Moreover, the intestinal microflora- most appropriate antiplatelet drugs and interventions can
targeted inhibitor iodomethylcholine is an intestinal improve therapeutic outcomes and reduce the incidence of
microbial choline TMA lyase inhibitor based on the adverse reactions.
prototype mechanism and has been shown to block the
elevation of TMAO induced by a choline-rich diet. 57 9. Conclusion
As is well known, atherosclerosis, hypertension, There is a clear link between the occurrence and incidence
thrombosis, and atrial fibrillation are high-risk factors of IS and the levels of TMAO, underscoring the potential
for IS. We hypothesize that TMAO is a risk factor role of TMAO in the management and prevention of stroke
for IS as well. Moreover, TMAO may be used as a and as a biomarker for the early detection of IS in the future.
biomarker to predict the severity of a stroke. One study It is therefore important to research therapy strategies to

Volume 3 Issue 3 (2024) 5 doi: 10.36922/an.3005