Navigating a challenging path: precision disease treatment with tailored oral nano-armor-probiotics

Abstract

Oral probiotics have significant potential for preventing and treating many diseases. Yet, their efficacy is often hindered by challenges related to survival and colonization within the gastrointestinal tract. Nanoparticles emerge as a transformative solution, offering robust protection and enhancing the stability and bioavailability of these probiotics. This review explores the innovative application of nanoparticle-armored engineered probiotics for precise disease treatment, specifically addressing the physiological barriers associated with oral administration. A comprehensive evaluation of various nano-armor probiotics and encapsulation methods is provided, carefully analyzing their respective merits and limitations, alongside strategies to enhance probiotic survival and achieve targeted delivery and colonization within the gastrointestinal tract. Furthermore, the review explores the potential clinical applications of nano-armored probiotics in precision therapeutics, critically addressing safety and regulatory considerations, and proposing the innovative concept of 'probiotic intestinal colonization with nano armor' for brain-targeted therapies. Ultimately, this review aspires to guide the advancement of nano-armored probiotic therapies, driving progress in precision medicine and paving the way for groundbreaking treatment modalities.

Keywords: Gut to brain; Nanoparticles; Oral administration; Precision therapy; Probiotics.

Fig. 1

Precision disease treatment with tailored oral nano-armor-probiotics

Fig. 2

Timeline of selected items in the history of probiotic-related terms [40]. Copyright © 2019 Martín and Langella

Fig. 3

Adverse environment encountered by probiotics during a storage, b gastrointestinal transport, and c functions of armor probiotics in vivo [72]. © 2024 Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies

Fig. 4

a schematic illustration of the barriers to oral drug delivery (pH variations, microbiota content, mucus thickness) between the stomach and colon [73]. © 2021 Elsevier B.V. All rights reserved. b The double-layered multinucleated microcapsules were prepared by mixing SN15-2 as probiotics with inner core microspheres and calcium alginate as the shell material [75]. Copyright ©2023 American Chemical Society.c Characterization of artificial-enzyme-armed probiotic [76]. Copyright © 2023, The Author(s), under exclusive licence to Springer Nature Limited

Fig. 5

a schematic illustration of the synthesis progress of Au/CeO₂@HA [185]. © 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. b Schematic illustration of synthesis progress of D-AuNPs [186]. c Schematic Illustration Showing the Construction Procedures of EcN@SiH System and Its Applications in Probiotic/Gas Dual-Mode Therapy for the Treatment of IBD [187]. Copyright ©2023 American Chemical Society.d Schematic illustration of P-bioHJ formation [188]. © 2024 Wiley-VCH GmbH. e Construction of the Yeast@LOX@ZIF-8 (YLZ) bioreactor [189]. © 2021 Elsevier Ltd. All rights reserved. f Synthetic magnetized BL21(DE3) E. coli cells expressing mScarlet to facilitate downstream quantification using flow cytometry. The color change in the tube in the right inset indicates the simulated magnetic field strength at a distance of z = 10–13 mm from the surface of the N52 magnet. The orange arrows indicate the direction of magnetization of the permanent magnet, while the orange dashed ellipses indicate the magnetic lines of force generated by the external magnet as well as the micro magnets inside the tube. The coordinate system is oriented so that gravity acts in the + y direction and the center of the magnet is located at (y = 40, z = 0) [190]. © 2021 Wiley-VCH GmbH

Fig. 6

a schematic representation of pBDT-TA nanoparticles prepared by π-π interaction with BDT and TA. Escherichia coli Nissle 1917 (EcN) coated the sodium alginate (SA) layer and pBDT-TA onto the SA surface by electrostatic interactions [204]. Copyright ©2024 American Chemical Society. b Schematic representation of the formation of SCLR and OASCLR [205]. Copyright © 2022, © The Author(s) 2022. Published by Oxford University Press on behalf of China Science Publishing & Media Ltd. c Schematic representation of the procedure of loading LGG into nanofibres and filling the fibers with either Streptococcus-resistant spray-dried LGG (StrepR) or Rif-resistant LGG (RifR) (or opposite combinations) in capsules for a schematic representation of the procedure performed to perform a competition study between the two forms of LGG dosed into individual rats [206]. © 2021 Elsevier Ltd. All rights reserved. d Blood calcium levels after administration of elcatonin-loaded nanospheres (100 IU/kg) to the lungs of male guinea pigs (6 weeks). (■) Elcatonin solution; (▲) uncoated PLGA nanospheres; (●) chitosan-coated PLGA nanospheres. Data are expressed as mean ± S.D. (n = 5). p < 0.001, *p < 0.05 vs. Elcatonin solution [207]. Copyright © 2004 Elsevier B.V. All rights reserved

Fig. 7

Strategies for efficient oral delivery via lipid-based nanocarriers [211]. a Improvement of the stability of nanocarriers in the harsh gastrointestinal environment that includes enzymes, salts, and microbiota. b Enhancement of mucoadhesion. Nanocarriers remain adhered to the mucus and thereby their residence time is increased. The cargo molecule may be released. c Enhancement of immunodiffusion. Nanocarriers diffuse through the mucus, increasing the chances for their interaction with the epithelium. d Inhibition of P-glycoprotein. Drug efflux may be decreased, increasing drug-effective absorption. e Active targeting. f Enhancement of lymphatic transport, transport pathway that avoids first pass effect. Copyright©2021, Controlled Release Society

Fig. 8

a schematic illustration of the development of engineered probiotics for multipronged management of IBD (a) and the characterization of EcN-Fh [214]. Copyright©2024, American Chemical Society. b Preparation of carboxymethyl konjac glucan-chitosan (CMKGM-CS) nanogels and their biological effects [215]. © 2023 Elsevier Ltd. All rights reserved. c Schematic diagram of in vitro digestion behavior of alginate hydrogel beads coated W1/O/W2 double emulsions [216]. © 2022 Published by Elsevier Ltd

Fig. 9

a Methods of surface decoration [222]. © 2022 Elsevier B.V. All rights reserved. b Probiotic encapsulation by the bacteria-induced colloidal assembly [223]. Copyright©2023, American Chemical Society. c EcN-ca-DOX was obtained by conjugation of DOX molecules onto EcN [224]. ©2017 Elsevier B.V. All rights reserved. d Flow chart of preparation of nanoparticles by two different methods: antisolvent co-precipitation (M1-ASCP) and antisolvent precipitation (M2-ASP) [225]. © 2022 Elsevier Ltd. All rights reserved. e EcN deactivation by restraining inside mineralized coating and reactivation by removing the coating in response to physiological gastric acid stimulation [226]. © 2023 Wiley-VCH GmbH. f Mass production of EcN@AN with high-throughput microfluidics, gastrointestinal resistance, and on-demand delivery of encapsulated probiotics [227]. Copyright©2024, American Chemical Society

Fig. 10

Schematic illustration of preparing tumor-resident living immunotherapeutics by decorating bacteria with triple immune nanoactivators [229]. ©2022Wiley-VCH GmbH. a Conjugation of tumor-specific antigen OVA and immune checkpoint inhibitor α-PD-1 to PDA nanoparticles, which are attached to the bacterial surface through in situ precipitation polymerization of dopamine. b Decorated bacteria-mediated reversal of the tumor immunosuppressive microenvironment via repolarization of TAMs, maturation of dendritic cells, and activation of cytotoxic T lymphocytes

Fig. 11

Schematic illustration of the fabrication of EcN@Fe-TA@mGN and its alleviation process for DSS-induced colitis in mice [235]. Copyright © 2023, American Chemical Society. a Preparation of EcN@Fe-TA@mGN. First, bacterial suspension was stirred with TA and Fe³⁺ for 60 s to form a Fe-TA network layer on EcN. Then, they were encapsulated by mGN through simple agitation. b Probiotics exhibited a superior resistance to gastric acids and bile salts after being armed with an Fe-TA@mGN “shield” and remained intact in the upper digestive tract. Once EcN@Fe-TA@mGN reached the colon, the mGN layer would be degraded by gut microbiota and metabolized to SCFAs to synergize with EcN for the alleviation of colitis. The exposed Fe-TA layer would aid the colonization of EcN in colon for the realization of sustainable functions

Fig. 12

a Schematic illustration of bioorthogonal-mediated bacterial delivery to enhance probiotics colonization in the gut [239]. Copyright © 2022 The Authors. Published by American Chemical Society. b Illustration of the prebiotics-encapsulated probiotics to regulate gut microbiota and suppress colon cancer. Bacteria specifically enriching in tumor tissues were screened. C. butyricum was then modified with prebiotic dextran by host–guest chemistry. The system that carried the chemotherapeutic drugs was used orally by mice for colon cancer treatment [240]. © 2020 Wiley-VCH GmbH

Fig. 13

a Anti-Solvent Precipitation of Zein. b Layer-by-Layer Assembled L. plantarum 550 Microcapsule Using Zein Nanoparticles and Pectin [242]. © 2023 Elsevier Ltd. All rights reserved

Fig. 14

Schematic illustration of biointerface mineralization that generates ultraresistant gut microbes as oral biotherapeutics [245]. a Preparation of mineral coating on bacterial surface. b Resistances of coated bacteria against environmental assaults. c Neutralization of gastric acid, adaptable release of coated bacteria, and calcium ions–triggered aggregation of bile acid by double-decomposition reaction of mineral coating in the gastrointestinal tract following oral ingestion

Fig. 15

Schematic diagram of the action of nano-armor-probiotics in the treatment of diseases

Fig. 16

a the preparation of LA&LDH [252]. © 2023 Wiley-VCH GmbH. b Synthesis schemes of CS-ID@NMs [253]. © 2022 Wiley-VCH GmbH.c Fluorescence intensity of SOSG [252]. © 2023 Wiley‐VCH GmbH. d GSH concentrations [253]. © 2023 Wiley-VCH GmbH. e B16-F0 tumor growth curve of Rag−/− mice that received an adoptive cell transfer (ACT) of 5 × 105 CD8 T cells from WT donor mice 1 day before TCE and were treated with orally administered Lr or PBS daily starting 1-day pTCE (n = 3 per group) [254]. © 2023 Elsevier Inc. f B16-F0 tumor growth of mice orally administered Lr or PBS daily starting on day 5 pTCE (tumor size ∼100 mm³) and treated with intraperitoneal injections (IP) of 50 µg αPD-L1 or isotype control (iso. ctrl.) on days 5, 7, 9, and 12 pTCE (n = 4–6 mice/group) [254]. © 2023 Elsevier Inc

Fig. 17

Natural polyphenol-based single-cell coating (nanoarmor) for the protection of bacteria from antibiotics in the gastrointestinal (GI) tract [262]. Copyright © 2022, The Author(s). a The nanoarmor enables a rapid and highly biocompatible single-cell encapsulation that protects from a wide range of antibiotics with different molecular structures and properties. b Armored probiotic bacteria can be freeze-dried and filled into enteric capsules designed for oral delivery. c The enteric capsule remains intact during the low pH of gastric transit and releases the armored probiotics in the gut. d The poor specificity of antibiotics normally depletes healthy commensals in the gut and hinders probiotic treatments. e The nanoarmor provides a safe and transient coating to the beneficial bacteria from antibiotics, facilitating healthy microbe repopulation

Fig. 18

MON-PEI reduces cfDNA- and ROS-induced inflammation in vitro [263]. a Schematic of the design of a biodegradable nanomedicine with cfDNA- and ROS-scavenging activity for IBD therapy. b Transmission electron microscopy images of MON before and after a 1-day incubation in simulated body fluid solution containing 100 µM H2O2. c DNA binding efficiency of MON, PEI, and MON-PEI at different nanoparticle: DNA mass ratios at 37 °C. d Viability of Caco-2 cells treated for 24 h with various concentrations of MON, PEI, and MON-PEI. e Activation of HEK-TLR9 reporter cells by IBD patient sera in the absence or presence of MON, PEI, and MON-PEI for 24 h. The corresponding SEAP activity in supernatants from each group was determined with a QUANTI-Blue assay at OD620. f RAW 264.7 macrophages were stimulated with IBD patient sera in the absence or presence of MON, PEI, and MON-PEI for 24 h. Supernatants were assayed for TNF-α by ELISA. g Relative fluorescence intensity of oxidized DCF in Caco-2 cells after incubation with different formulations in the presence or absence of 100 µM H2O2 for 4 h. h The viability of Caco-2 cells was measured after treatment with different formulations in the presence of 100 µM H2O2 for 24 h. Data are means ± SEM (n = 3 independent experiments; *P < 0.05, **P < 0.01, and ***P < 0.001 by one-way ANOVA with Tukey’s multiple comparison test)

Fig. 19

Related strategies and future scope to address the potential issues regarding probiotic limitations and market confusion [274]. Rights managed by Taylor & Francis

Fig. 20

Pathways of communication along the gut-microbiota-brain axis [279]. A complex interplay of epithelial, immune, and neural cell signaling networks is involved in sensing and communicating changes in microbial metabolites in the gut and the brain involving both circulatory and neural routes

Fig. 21

Illustration of the bionic dormant body timed-triggering to treatment PD by suppressing p38MAPK/NF-κB-mediated signaling pathway in microglia [284]. aL. plantarum is coated with L30D-55 and taken orally to avoid the insult of gastric fluid and decipher in the intestine. b GABA synthesized by L. plantarum in the intestine enters the brain by the blood-brain barrier (BBB) and reduces neuroinflammation by inhibiting the p38MAPK/NF-κB-mediated signaling pathway in the microglia to rescue the loss of dopaminergic neurons for treatment PD. Copyright © 2022, American Chemical Society

Fig. 22

Modulation of intestinal bacteria by EcN@PC-Fe/HA during colitis treatment [287]. © 2024 Wiley-VCH GmbH. Comparison of alpha diversity assessed by a Chao1 index, b Shannon index, and c observed species. d Clustering of gut microbial communities for different experimental groups based on the PCoA plot with Weighted_Unifrac distance. e Column diagram of the relative abundance of gut microbiome at the phylum level. f Effects of EcN@PC-Fe/HA on microbial composition at order levels using ternary plot method. g Cladogram based on Linear discriminant analysis effect size (LEfSe) analysis showing community composition of the gut microbiota in mice. h Distribution histogram based on linear discriminant analysis (LDA). LDA score higher than 3 indicates a higher relative abundance in the corresponding group than that in other groups. LDA (log10) > 4.0, P < 0.05. i Heatmap of the functional prediction of altered gut microbiota based on KEGG pathways. Data are presented as means ± SD (n = 5). Statistical analysis was performed using Student’s t-test. *P < 0.05, **P < 0.01

Fig. 23

The schematic illustration of mechanism exploration on gut bacterial metabolites in MGB using synthetic living delivery bacteria [289]. a The schematic illustration of mechanism exploration on gut bacterial metabolites in MGB using synthetic living delivery bacteria.b Overview of the experimental design and treatment schedule. C57BL/6J mice were exposed to CUMS for 8 weeks (marked as “CUMS” under the black line). From the onset of the 5th week to the end of CUMS exposure, depressed mice were dosed with saline (abbreviated as “SAL”), wild-type EcN (marked as “EcN”), and a butyrate-overproducing recombinant EcN M3P2TA (abbreviated as “eEcN”), respectively. The healthy mice were marked as “CON”. c-e Bar plots of the results in behavioral tests were shown, including ` c sucrose preference test, d forced swim test, e tail suspension test. n = 8–9 per group. Data are shown as mean ± SEM