Medical Bulletin 23/ April/ 2024

In a recent review published in the journal Current Developments in Nutrition, researchers assessed the therapeutic potential of cruciferous vegetables and their bioactive compounds in managing inflammatory bowel disease (IBD) using in vitro, in vivo, and clinical models.

Cruciferous veggies like broccoli and cabbage are packed with nutrients and special compounds called glucosinolates (GSLs). When we eat these veggies, an enzyme called myrosinase converts GSLs into isothiocyanates (ITCs). These ITCs have been studied for their ability to reduce inflammation and oxidative stress, which are important factors in inflammatory bowel disease (IBD). These vegetables have more helpful compounds like flavonoids and polyphenols. Together, these compounds not only fight inflammation and oxidative stress but also make the gut stronger and balance the gut bacteria, thus helping ease symptoms of IBD.

Research has highlighted the therapeutic potential of cruciferous vegetables in inflammatory bowel disease (IBD). In vitro studies reveal their anti-inflammatory properties, inhibiting key pathways in immune cell-mediated inflammation, while their antioxidant effects combat oxidative stress, a major contributor to IBD. Animal studies support these findings, showing that diets rich in cruciferous vegetables alleviate IBD symptoms, improve gut microbiota composition, increase short-chain fatty acid production, and enhance intestinal barrier integrity.

In experiments involving mice, feeding them broccoli extracts rich in SFN led to lower levels of inflammatory markers like TNF-alpha and IL-6. Additionally, it increased the levels of protective proteins in the gut lining, like ZO-1. This suggests that SFN not only reduces inflammation but also strengthens the gut lining, which is often weakened in people with IBD.

Additionally, future research aim to understand the individualized responses to cruciferous vegetable intake in different subpopulations of IBD patients. This could help tailor dietary recommendations to enhance individual patient outcomes and develop personalized nutritional therapies that are both effective and manageable over the long term.

Reference: TE Alaba, J.M. Holman, S.L. Ishaq, et al, Current knowledge on the preparation and benefits of cruciferous vegetables as relates to in vitro, in vivo, and clinical models of Inflammatory Bowel Disease., Current Developments in Nutrition, DOI - 10.1016/ j.cdnut.2024.102160, https://cdn.nutrition.org/article/S2475-2991(24)00094-5/fulltext

In a study published in Environmental Health Perspectives, researchers examined how consuming microplastics in amounts similar to those found in our environment affected mice.

Microplastics, found in various substances, are ubiquitous in the environment, from soil to food and water. Upon ingestion, they traverse the digestive tract and can enter the bloodstream through the gut lining. These particles can circulate throughout the body, potentially reaching the blood-brain barrier, which normally shields the brain from harmful substances. Under certain conditions, smaller microplastic particles may breach this barrier, accumulate, and possibly induce adverse effects.

In the study, researchers sought to understand the impact of different types of microplastics on various organs in mice. They defined microplastics as plastic particles smaller than 5 millimeters and aimed to replicate human exposure levels. Mice were orally fed varying amounts of polystyrene or mixed polymer microspheres. After ingestion, the researchers examined serum, brain, liver, kidney, and colon tissues to assess the presence of microplastics and any resulting effects.

The results showed microplastics in multiple organs including the brain, liver, and kidneys of exposed mice. These findings show how microplastics are capable of spreading to other, distant areas of the body. After microplastic exposure, they also found that specific metabolic changes occurred in the colon, liver, and brain. These changes depended on how much exposure the mice received and what type of microplastic they were exposed to.

“Previous research from our group has demonstrated that microplastics can disrupt immune function. This could be a problem when dealing with infections or could possibly worsen conditions like inflammatory bowel diseases. Additionally, our study was performed over a 4-week period, showing significant alterations in metabolism. This brings insight into the long-term accumulation of microplastics in the body, raising concerns about chronic exposure. Furthermore, our study revealed substantial metabolic alterations linked to various metabolic and immune disorders, including changes in amino acid, lipid, and hormone metabolism,” said study author Marcus Garcia, postdoctoral fellow at the University of New Mexico College of Pharmacy.

Reference: Marcus M. Garcia, Aaron S. Romero, Seth D. Merkley, et al,; In Vivo Tissue Distribution of Polystyrene or Mixed Polymer Microspheres and Metabolomic Analysis after Oral Exposure in Mice; Environmental Health Perspectives; https://doi.org/10.1289/EHP13435

In a study published in the journal Scientific Reports, researchers from Loughborough University in the United Kingdom showed that a loss of visual sensitivity could predict Alzheimer’s disease 12 years before typical diagnosis.

Vision issues like difficulty reading, driving, or judging distances may signal early Alzheimer's disease, the most common form of dementia. Studies suggest that changes in the eyes, such as blood vessel damage and beta-amyloid plaques, may indicate Alzheimer's progression. Retinal scans and detecting plaques in the eye could offer noninvasive ways to diagnose the condition.

In the study, researchers analyzed data from over 8,000 healthy adults who underwent visual sensitivity testing. This test evaluated participants' visual processing speed and reaction time by prompting them to press the space bar when they observed a triangle forming among moving dots on a computer screen.

“We explored visual sensitivity as a potential predictor of dementia due to evidence suggesting that individuals with dementia often face visual processing difficulties, even in the early stages of the disease. Visual impairments have been associated with a higher risk of developing dementia in the future, indicating that assessing visual processing abilities could be beneficial for dementia risk evaluation,” said Ahmet Begde, a doctoral researcher in the School of Sport, Exercise, and Health Sciences at Loughborough University in the U.K

The results revealed that participants with lower scores on the visual sensitivity test had a higher risk of a future dementia diagnosis. Researchers noted that out of 8,623 healthy people about 6% (587) patients could develop dementia later in their life.

“We found that a low score on this test missing many targets can indicate future dementia risk, on average 12 years before the diagnosis, especially when using this test with other specific memory tests and some tests of global cognitive functioning worked well to predict this risk,” said Prof. Hogervorst, lead author of this study.

Reference: Begde, A., Wilcockson, T., Brayne, C. et al. Visual processing speed and its association with future dementia development in a population-based prospective cohort: EPIC-Norfolk. Sci Rep 14, 5016 (2024). https://doi.org/10.1038/s41598-024-55637-x