The human gut microbiota plays a critical role in maintaining healthy gastrointestinal function and other physiological processes, including immune regulation, maintenance of homeostasis, and host health. Antibiotics are the most prescribed drugs in clinics because of their ability to kill disease-causing bacteria. However, their non-selective killing action also causes a decrease in the healthy microbiome, including some of the beneficial microbes in the gut, skin, and mucous membranes, which is known as ‘dysbiosis’. This disruption of beneficial microbes is increasingly associated with many harmful health conditions, including antibiotic-associated diarrhea, inflammation, allergic reactions, and even high levels of stress or anxiety. In addition, dysbiosis can also lead to diabetes, obesity, and neurological disorders.
To avoid these consequences, it is important for the body to restore the healthy balance of its microbiome as quickly as possible after, or even during, the necessary antibiotic treatment. Therefore, one of the most common reasons for seeking probiotics is to restore the balance of the microbiome in the gut with beneficial microorganisms during antibiotic therapy. However, their benefits are often compromised by the antibiotic treatment itself. In addition, the situation of simultaneous (or closely spaced) use of antibiotics and beneficial bacteria goes beyond the scope of oral probiotics, such as the treatment of fecal microbiota transplantation (FMT).
To protect probiotics from these adverse effects, Guo et al. have developed a method to coat probiotics, which consists of an adhesive material (named ‘probiotic nanoarmor’) derived from a plant extract component. This nanocoating was inspired by their previous studies on inorganic-organic hybrid surface functionalization (Angew. Chem. Int. Ed. 2014, 53, 5546), polyphenol-based interfacial assembly (Nat. Nanotechnol. 2016, 11, 1105), and cellular engineering (Science 2018, 362, 813, Adv. Mater. 2020, 32, 2003492). The nanoarmor protects a series of probiotics from six clinically relevant antibiotics. Multiple interactions between the nanoarmor and antibiotic molecules allow for the effective absorption of antibiotics into the nanoarmor. Armored probiotics have shown the ability to colonize the gastrointestinal tract of the levofloxacin-treated rats, which greatly reduced antibiotic-associated diarrhea (AAD) caused by levofloxacin treatment and ameliorated some of the pro-inflammatory symptoms caused by AAD. This strategy presents a powerful platform and promising live biotherapeutic product (LBP) to improve the efficacy of conventional therapeutic bacteria in the gastrointestinal tract for the patients who are receiving antibiotics and to avoid the adverse effects of antibiotics in the gastrointestinal tract.