Bacteroides ovatus heightens metformin’s impact on vitamin B12 deficiency.

Bacteroides ovatus accelerates metformin-induced vitamin B12 deficiency in type 2 diabetes patients by accumulating cobalamin

Introduction

Metformin is a commonly used medication for managing type 2 diabetes. However, it has been associated with vitamin B12 deficiency, leading to hematologic and neurologic symptoms. The underlying mechanism of this relationship is unclear. In a recent study published in the npj Biofilms and Microbiomes journal, researchers discovered that Bacteroides ovatus, a gut bacteria, plays a role in accelerating metformin-induced vitamin B12 deficiency in patients with type 2 diabetes.

Study Findings

The study involved a prospective patient cohort of newly diagnosed type 2 diabetes patients who received metformin treatment for 3 to 6 months. The researchers found that patients with a high abundance of Bacteroides ovatus in their gut had a higher risk of vitamin B12 deficiency after metformin treatment. This was evidenced by lower serum levels of vitamin B12 and higher levels of homocysteine, a biomarker for vitamin B12 deficiency.

Through further experiments using mice, the researchers observed that colonization of Bacteroides ovatus in the gut increased the absorption and consumption of vitamin B12, leading to a deficiency in the host. They also found that metformin treatment upregulated the expression of microbial genes involved in vitamin B12 uptake and transport. This increased the capacity of Bacteroides ovatus to compete with the host for vitamin B12 and exacerbated the deficiency.

Implications and Importance

The findings of this study shed light on the previously unappreciated role of gut bacteria in metformin-induced vitamin B12 deficiency. It highlights the importance of monitoring vitamin B12 levels in patients taking metformin, especially those with high levels of Bacteroides ovatus in their gut. Regular testing and potential supplementation of vitamin B12 can help prevent or offset the negative effects of the deficiency.

Furthermore, these findings also point to the broader impact of inter-host-microbe competition for nutrients on human health and drug safety. Understanding the complex interactions between the gut microbiota, medications, and nutrient absorption can lead to personalized approaches to treatment and improved patient outcomes.

Editorial and Advice

Metformin is a widely used medication for managing type 2 diabetes due to its effectiveness in lowering blood glucose levels. However, it is important for healthcare professionals to be aware of the potential side effects, such as vitamin B12 deficiency, that can arise from long-term use. Regular monitoring of vitamin B12 levels, especially in patients with risk factors such as high levels of Bacteroides ovatus in the gut, can help identify and address deficiencies early on.

In addition, patients taking metformin should consider incorporating vitamin B12-rich foods into their diet or taking supplements to ensure an adequate intake. It is also important for healthcare professionals to educate patients about the potential risks and benefits of metformin treatment, as well as the importance of regular follow-up and monitoring of their overall health.

Overall, this study highlights the intricate relationship between medications, gut bacteria, and nutrient absorption. Further research is needed to fully understand these interactions and develop personalized treatment strategies that minimize the side effects while maximizing the benefits of medications like metformin for patients with type 2 diabetes.