Tag: B vitamins

Categories : Gastrointestinal Neurodegenerative DiseasesTags :

Gut Bacteria in Parkinson’s Disease Produce Fewer B Vitamins

On By ModernMedia
In Parkinson’s disease, a reduction in the gut bacteria of genes responsible for synthesising the essential B vitamins B2 and B7 was found. Credit: Reiko Matsushita

A study led by Nagoya University in Japan has revealed a link between gut microbiota and Parkinson’s disease (PD). The researchers found that the gut bacteria genes responsible for synthesising vitamins B2 and B7 were reduced. This gene reduction was also linked to low levels of agents that help maintain the integrity of the intestinal barrier, which when weakened causes the inflammation seen in PD. Their findings, published in npj Parkinson’s Disease, suggest that treatment with B vitamins to address these deficiencies can be used to treat PD. 

PD is characterized by a variety of physical symptoms that hinder daily activities and mobility, such as shaking, slow movement, stiffness, and balance problems. While the frequency of PD may vary between different populations, it is estimated to affect approximately 1-2% of individuals aged 55 years or older. 

Various physiological processes are heavily influenced by the microorganisms found in the gut, which are collectively known as gut microbiota. In ideal conditions, gut microbiota produce SCFAs and polyamines, which maintain the intestinal barrier that prevents toxins entering the bloodstream. Toxins in the blood can be carried to the brain where they cause inflammation and affect neurotransmission processes that are critical for maintaining mental health.

To better understand the relationship between the microbial characteristics of the gut in PD, Hiroshi Nishiwaki and Jun Ueyama from the Nagoya University Graduate School of Medicine conducted a metanalysis of stool samples from patients with PD from Japan, the United States, Germany, China, and Taiwan. They used shotgun sequencing, a technique that sequences all genetic material in a sample. This is an invaluable tool because it offers researchers a better understanding of the microbial community and genetic makeup of the sample.

They observed a decrease in the bacterial genes responsible for the synthesising of riboflavin (vitamin B2) and biotin (vitamin B7) in patients diagnosed with PD. Riboflavin and biotin, derived from both food and gut microbiota, have anti-inflammatory properties, which may counteract the neuroinflammation seen in diseases like PD. 

B vitamins play crucial roles in the metabolic processes that influence the production and functions of short-chain fatty acids (SCFAs) and polyamines, two agents that help maintain the integrity of the intestinal barrier, preventing toxins entering the bloodstream. An examination of fecal metabolites revealed decreases of both in patients with PD. 

The findings indicate a potential explanation for the progression of PD. “Deficiencies in polyamines and SCFAs could lead to thinning of the intestinal mucus layer, increasing intestinal permeability, both of which have been observed in PD,” Nishiwaki explained. “This higher permeability exposes nerves to toxins, contributing to abnormal aggregation of alpha-synuclein, activating the immune cells in the brain, and leading to long-term inflammation.” 

He added, “Supplementation therapy targeting riboflavin and biotin holds promise as a potential therapeutic avenue for alleviating PD symptoms and slowing disease progression.”

The results of the study highlight the importance of understanding the complex relationship among gut microbiota, metabolic pathways, and neurodegeneration. In the coming years, customised therapy could potentially be based on patients’ unique microbiome profiles. By altering bacterial levels in the microbiome, doctors can potentially delay the onset of symptoms associated with diseases like PD.

“We could perform gut microbiota analysis on patients or conduct faecal metabolite analysis,” Nishiwaki said. “Using these findings, we could identify individuals with specific deficiencies and administer oral riboflavin and biotin supplements to those with decreased levels, potentially creating an effective treatment.”

Source: Nagoya University

The study, “Meta-analysis of shotgun sequencing of gut microbiota in Parkinson’s disease,” was published in npj Parkinson’s Disease on May 21, 2024, at DOI:10.1038/s41531-024-00724-z.

Categories : Cardiovascular DiseaseTags :

High Levels of Niacin Linked to Cardiovascular Disease

On By ModernMedia
Photo by Robina Weermeijer on Unsplash

Cleveland Clinic researchers have identified a new pathway that contributes to cardiovascular disease associated with high levels of niacin, a common B vitamin previously recommended to lower cholesterol.

The team, led by Stanley Hazen, MD, PhD, reported in Nature Medicine that they had found a link between 4PY, a breakdown product from excess niacin, and cardiovascular disease. Higher circulating levels of 4PY were strongly associated with development of heart attack, stroke and other adverse cardiac events in large-scale clinical studies.

The researchers also showed in preclinical studies that 4PY directly triggers vascular inflammation which damages blood vessels and can lead to atherosclerosis over time. The study also details genetic links between 4PY and vascular inflammation.

The findings provide a foundation for potential new interventions and therapeutics to reduce or prevent that inflammation.

“What’s exciting about these results is that this pathway appears to be a previously unrecognised yet significant contributor to the development of cardiovascular disease,” said Dr Hazen, Chair of Cardiovascular and Metabolic Sciences at Cleveland Clinic’s Lerner Research Institute and Co-Section Head of Preventive Cardiology in the Heart, Vascular & Thoracic Institute.

“What’s more, we can measure it, meaning there is potential for diagnostic testing. These insights set the stage for developing new approaches to counteract the effects of this pathway.”

Niacin (vitamin B-3) is very common in a Western diet. “For decades, the United States and more than 50 nations have mandated niacin fortification in staple foods such as flour, cereals and oats to prevent disease related to nutritional deficiency,” said Dr Hazen.

Yet one in four subjects in the researchers’ patient cohorts appear to be getting too much, and had high levels of 4PY, which appears to contribute to cardiovascular disease development.

Dr. Hazen compares our intake of niacin as multiple taps pouring water into a bucket.

Once that bucket is filled, it begins to spill over. The human body then needs to process that spill-over and produce other metabolites, including 4PY.

“The main takeaway is not that we should cut out our entire intake of niacin – that’s not a realistic approach,” said Dr Hazen.

“Given these findings, a discussion over whether a continued mandate of flour and cereal fortification with niacin in the US could be warranted.”

Dr. Hazen notes broader use of over-the-counter supplements made with different forms of niacin have also become popular because of presumed anti-aging purposes.

He adds that patients should consult with their doctors before taking over-the-counter supplements and focus on a diet rich in fruit and vegetables while avoiding excess carbohydrates.

The new findings also might help explain why niacin, one of the first treatments prescribed to lower LDL cholesterol, is no longer a go-to treatment for for this.

Eventually niacin was shown to be less effective than other cholesterol-lowering drugs and was associated with other negative effects and higher mortality rates in previous research.

“Niacin’s effects have always been somewhat of a paradox,” Dr Hazen said.

“Despite niacin lowering of cholesterol, the clinical benefits have always been less than anticipated based on the degree of LDL reduction. This led to the idea that excess niacin caused unclear adverse effects that partially counteracted the benefits of LDL lowering. We believe our findings help explain this paradox. This illustrates why investigating residual cardiovascular risk is so critical; we learn so much more than what we set out to find.”

The study authors note that long-term investigations are needed to assess the effect of chronic elevation of 4PY levels on atherosclerosis and other phenotypes.

Source: Cleveland Clinic