We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Micro-nanoplastics inhibit extracellular polymeric substance and lactate synthesis via perturbing glucose metabolism of Lacticaseibacillus rhamnosus
Summary
Researchers found that micro- and nanoplastics — especially nanoscale PET particles — impair the probiotic bacterium Lactobacillus rhamnosus by disrupting central carbon metabolism, reducing its production of lactic acid and protective extracellular polysaccharides, raising concerns that microplastic ingestion could compromise the gut benefits of probiotic bacteria.
Micro-nanoplastics (MNPs) ubiquitously occurring in various ecosystems can accumulate in the human gastrointestinal tract via multiple exposure routes, and threaten the intestinal homeostasis. However, clarifying whether and how these contaminants cause the physio-toxicity to intestinal probiotics remains elusive. Using Lacticaseibacillus rhamnosus as a case study and an in vitro digestion (IVD) system to simulate MNPs digestion, we found that MNPs inhibit bacterial growth and the synthesis of extracellular polymeric substances (EPS) and lactic acid (LA). This toxicity depended on material composition (polyethylene terephthalate, PET > polystyrene > polyvinyl chloride), was enhanced at the nanoscale, and was exacerbated by high concentrations. Under the strongest inhibitory condition (150.0 nm 250.0 mg/L IVD-treated PET; PET-NPs), scanning electron microscopy reveals that EPS secreted by L. rhamnosus under PET-NPs stimulation binds to the particles and adheres to the bacterial surface, potentially causing physical obstruction and membrane damage. Integrated transcriptomics and metabolomics demonstrated that IVD-treated PET-NPs significantly down-regulated core genes (e.g., galK, logFC = -5.40; bglA, logFC = -6.58), and reduced metabolite levels in central carbon metabolism pathways (e.g., phosphotransferase system, glycolysis, TCA cycle, pentose phosphate pathway, oxidative phosphorylation), impairing glucose uptake/metabolism and energy generation, and thus limiting precursor supply for EPS and LA synthesis. Although exogenous glucose partially restored function, upstream metabolic damage persisted. The findings indicate that MNPs disrupt the glucose metabolism-product synthesis axis by inhibiting central carbon metabolism, providing clear evidence of MNP-mediated impairment of metabolism and efficacy in probiotics and mechanistic insights into the potential health impacts of MNPs contaminants.
Sign in to start a discussion.
More Papers Like This
Nanoplastics from single-use polyethylene terephthalate bottles impair the functionality of human gut-dwelling Lactobacillus rhamnosus and induce toxicity in human cells
Researchers synthesized nanoplastics from single-use PET water bottles and tested their effects on the gut probiotic Lactobacillus rhamnosus, red blood cells, and human lung cells. They found that the nanoplastics reduced probiotic survival in a dose-dependent manner, damaged cell membranes, and impaired the bacteria's beneficial functions including antioxidant activity. The study provides evidence that nanoplastics released from everyday plastic bottles could disrupt important gut bacteria and harm human cells.
Lactic acid bacteria reduce polystyrene micro- and nanoplastics-induced toxicity through their bio-binding capacity and gut environment repair ability
Researchers found that lactic acid bacteria, the kind used in yogurt and fermented foods, can reduce the toxic effects of polystyrene micro and nanoplastics in mice. The bacteria worked by physically binding to the plastic particles and by repairing damage to the gut lining and restoring healthy gut bacteria populations. This suggests that probiotics could be a practical way to help protect the digestive system from the harmful effects of microplastic exposure through food and water.
Lactobacillus plantarum reduces polystyrene microplastic induced toxicity via multiple pathways: A potentially effective and safe dietary strategy to counteract microplastic harm
Researchers found that Lactobacillus plantarum, a probiotic bacterium commonly found in fermented foods, can reduce the harmful effects of polystyrene microplastics in mice through multiple pathways. The bacteria worked by binding directly to plastic particles to help remove them from the body, reducing oxidative damage, repairing the intestinal barrier, and regulating bile acid metabolism. This suggests that certain probiotics could be a safe dietary strategy to help counteract some of the negative health effects of microplastic exposure.
Incorporation of polylactic acid microplastics into the carbon cycle as a carbon source to remodel the endogenous metabolism of the gut
Researchers discovered that gut bacteria can break down so-called biodegradable PLA microplastics and incorporate the carbon into their own metabolism, fundamentally altering the gut's energy balance. This process reduced beneficial short-chain fatty acids that fuel gut lining cells and caused decreased appetite and weight loss in mice, suggesting that biodegradable plastics may not be as harmless inside the body as assumed.
Polystyrene and polytetrafluoroethylene nanoplastics affect probiotic bacterial characteristics and penetrate their cellular membrane
This study found that polystyrene and PTFE nanoplastics damage the membranes and viability of probiotic bacteria in ways that differ by particle surface chemistry and bacterial strain. Since gut microbiome stability depends on these beneficial bacteria, this research suggests that nanoplastic ingestion could undermine the health benefits of probiotics and more broadly disrupt the gut microbial community.