Multiple sclerosis (MS) is a chronic, autoimmune disease characterized by central nervous system (CNS) inflammation, demyelination, and axonal loss. MS affects 2.5 million people worldwide, and imposes major burdens on individuals and society.
The etiology of the disease is considered to be multifactorial, including genetics and environmental factors. Dysregulation of immune responses and abnormal metabolism in MS patients suggest that multiple systems are involved in its pathophysiology.
Studies have demonstrated that human gut microbiota modulate extra-intestinal immune and metabolic responses. Recent human studies have shown slight to moderate differences at the whole gut microbiome community level between MS patients and healthy controls.
New Study Results
In a recently published study, researchers performed a longitudinal study to evaluate the host immune status, metabolome, gut microbiome, and dietary habits in MS patients in comparison to healthy controls, who were followed-up for 6 months. The research was published in the journal eBioMedicine.
The study included 49 participants from the John L. Trotter MS Center of WUSM from 2015-2018. Inclusion criteria for MS patients were patients with a diagnosis of MS, no DMT or steroid treatments in the past 3 months, ages 18-50, and not in clinical relapse at study enrolment. There were a total of 24 participants with MS and 25 control participants.
The study found a link between higher meat consumption and a decrease in the population of Bacteroides thetaiotaomicron in people’s gut microbiome. This bacteria is associated with digesting carbohydrates from vegetables. This link was found in both the MS participants and the healthy controls.
The research team found that together with chances in blood immune cells, metagenomic analysis identified a number of gut microbiota decreased in MS patients compared to healthy controls, and microbiota positively or negatively correlated with degree of disability in MS patients.
In the MS participants, the researchers also found an increase in T-helper 17 cells in the immune system, an increase in S-adenosyl-L’Methionine (SAM) in their blood, which is a meat-associated blood metabolite. They also observed an increase in proinflammatory markers. This is not the first study to have shown that an increased meat consumption can have a detrimental effect on our health. The studies have shown that red meat consumption can increase proinflammatory markers which of course can affect any individual, but even more so patients who already have a chronic inflammatory condition, like MS.
Claudia Cantoni, et al. Alterations of host-gut microbiome interactions in multiple sclerosis. eBioMedicine. 2022. DOI:https://doi.org/10.1016/j.ebiom.2021.103798
Photo by: Francisco Fernandez, M.D.