Medical Bulletin 15/ March/2024

According to a research published in the Journal BMJ Nutrition, Prevention and Health, daily consumption of three doses of Apple Cider Vinegar for a duration of between 4 and 12 weeks is associated with significant reductions in weight, body mass index, waist/hip circumferences and body fat ratio along with lowered blood glucose, triglyceride and cholesterol levels.

Obesity is a growing global health concern characterised by excessive body fat accumulation, often resulting from a combination of genetic, environmental and lifestyle factors and is associated with an increased risk of numerous chronic illnesses such as type 2 diabetes, cardiovascular diseases and several types of cancers.

In recent years, there has been increasing interest in alternative remedies to support weight management, and one such remedy was apple cider vinegar (ACV)- a type of vinegar made by fermenting apple juice. It contains vitamins, minerals, amino acids and polyphenols such as flavonoids, which are believed to contribute to its potential health benefits and has been used for centuries as a traditional remedy for various ailments.

For the research, a total of 120 overweight and obese adolescents and young adults were enrolled in and assigned to either the placebo group or experimental groups receiving increasing doses of ACV. Subjects consumed their normal diets throughout the study. The contents of daily meals and snacks were recorded in a diet diary. The physical activity of the subjects was also recorded. At weeks 0, 4, 8 and 12, anthropometric measurements, i.e., weight, body mass index, waist/hip circumferences and body fat ratio, were taken for all participants, and the level of glucose, triglycerides and total cholesterol were assessed by collecting 5 mL of fasting blood from each subject.

The results revealed that the addition of 5 mL, 10 mL or 15 mL of ACV to the diet resulted in significant decreases in body weight and BMI at weeks 4, 8 and 12 of the intake. Serum glucose levels decreased significantly by three doses of ACV at week 4, 8 and 12 compared with week 0. Triglycerides and total cholesterol levels decreased significantly at weeks 8 and 12. However, the placebo group did not experience any significant changes in the anthropometric variables throughout the study.

The findings of this study indicated that ACV consumption for 12 weeks led to a significant reduction in anthropometric variables and improvements in blood glucose, triglyceride and cholesterol levels in overweight/obese adolescents/adults and suggested that ACV might have potential benefits in improving metabolic parameters related to obesity and metabolic disorders in obese individuals.

Reference: Rony Abou-Khalil, Jeanne Andary, Elissar El-Hayek; Journal: BMJ Nutrition, Prevention & Health 2024; doi: 10.1136/bmjnph-2023-000823

A new research published in the Journal Nature revealed that gut bacteria and a diet rich in the amino acid tryptophan can play a protective role against pathogenic E. coli, which can cause severe stomach upset, cramps, fever, intestinal bleeding and renal failure.

Dietary tryptophan – an amino acid found mostly in animal products, nuts, seeds, whole grains and legumes – can be broken down by gut bacteria into small molecules called metabolites which can bind to a receptor on gut epithelial (surface) cells, triggering a pathway that ultimately reduces the production of proteins that E. coli uses to attach to the gut lining where they cause infection. When E. coli fail to attach and colonize the gut, the pathogen benignly moves through and passes out of the body.

Dopamine Receptor D2, or DRD2, present in peripheral tissues such as the gastrointestinal tract, plays a crucial role in gut function and helps in regulating various gastrointestinal processes, including motility, secretion, and sensation.

“It’s actually two completely different areas that this receptor could play a role in, which was not appreciated prior to our findings,” said Pamela Chang, associate professor of immunology in the College of Veterinary Medicine and of chemical biology in the College of Arts and Sciences. “We essentially think that DRD2 is moonlighting in the gut as a microbial metabolite sensor, and then its downstream effect is to help protect against infection.”

In the study, researchers used mice infected with C. rodentium, similar to E. coli, to study the protective effects of tryptophan in the gut. They found that a tryptophan-supplemented diet reduced pathogen levels and inflammation in the mice. Depleting gut bacteria with antibiotics removed this protective effect, confirming the role of gut microbes. Mass spectrometry identified three tryptophan metabolites boosted by the diet, each replicating the protective effect. Activation of DRD2 in human gut cells disrupted actin production, preventing pathogens like C. rodentium and E. coli from causing infection.

The findings revealed a new role of dopamine receptor DRD2 in the gut that controls actin proteins and affects a previously unknown pathway for preventing a pathogenic bacteria’s ability to colonize the gut.

Reference: Samantha A. Scott, Jingjing Fu & Pamela V. Chang; Journal: Nature; DOI: 10.1038/s41586-024-07179-5

A new study conducted by researchers at the University of Arizona Health Sciences identified a link between poor sleep and migraine attacks that suggested improving sleep health may diminish migraine attacks in people suffering from it.

The findings are published in the Journal Brain Communications.

Sleep disorders are commonly reported in people with migraine. Patients with migraines commonly experience sleep disturbances, including trouble falling or staying asleep, poor sleep quality, excessive daytime sleepiness, and waking up. Chronic migraine sufferers often report worse sleep quality, increased fatigue, and shorter sleep duration.

“It has been recognized for quite a long time that there is a relationship between sleep and migraine. The way it has been investigated in the past has been through patient-reported information, which is subjective. We quantitatively measured sleep in preclinical models and found that migraine-like pain does not influence sleep, but if you have disrupted sleep, your chances of having a migraine attack if you're a migraine patient are much higher.” said principal investigator Frank Porreca, PhD, research director for the Comprehensive Center for Pain & Addiction and professor of pharmacology at the UArizona College of Medicine – Tucson.

Led by Frank Porreca, a research team used mouse models to study sleep disruption, as their sleep patterns closely resemble those of humans. They assessed sleep using recordings and visual observations while keeping mice awake with novel objects to explore. The team discovered that sleep-deprived mice were more prone to experiencing migraine-like pain, but migraine-like pain did not disrupt their normal sleep patterns. They also highlighted that sleep deprivation can occur due to various factors, including stress.

The findings suggested that there is a directional causality in the relationship between migraine-like pain and sleep. While the pain phase of migraine does not disrupt sleep, sleep deprivation increases the likelihood of migraine-like pain. It should also be noted that increased sleep could increase the likelihood of migraine attack.

“Early morning is one of the most common times people experience migraine attacks. Migraine is highly female prevalent – it’s 3 to 1, women to men – and almost all the women are of childbearing age. Many people with migraine probably have children. They wake up with a migraine attack and are immediately stressed. The migraine attack is happening in the worst time of the day for function. Improved sleep is critically important and probably would diminish the frequency of migraine attacks.” concluded Porreca.

Reference: Robson C Lillo Vizin, Caroline M Kopruszinski, Paula M Redman, Hisakatsu Ito, Jill Rau, David W Dodick, Edita Navratilova, Frank Porreca; Journal: Brain Communications; DOI: 10.1093/braincomms/fcae051