Microenvironment Self-Adaptive Nanoarmor to Address Adhesion- and Colonization-Related Obstacles in Impaired Intestine Promote Bacteriotherapy Against Parkinson's Disease.

Partially acetylated chitosan oligosaccharides (CS) were used to create a nanoarmor that tunes adaptability and responsiveness for efficient interaction with the intestinal interface under dynamic conditions.

• The nanoarmor was designed to address adhesion- and colonization-related challenges posed by multiple physiological and pathological characteristics in the intestine.
• Partial acetylation of chitosan oligosaccharides was the key modification enabling microenvironment self-adaptive properties.
• The nanoarmor was designed to coat living probiotic bacteria (Lactobacillus plantarum ST-III).

Chitinase-3-like protein 1 (CHI3L1), an inflammation-related secreted glycoprotein, was identified as a colonization niche that facilitates probiotic colonization in pathological microenvironments.

• CHI3L1 is described as 'an inflammation-related secreted glycoprotein' that is upregulated in pathological intestinal microenvironments.
• The mechanism relies on 'the specific interaction between chitin-like fragment and CHI3L1.'
• This interaction was leveraged to promote selective colonization of nanocoated bacteria in inflamed intestinal tissue rather than healthy tissue.

Nanocoated bacteria demonstrated significantly improved performance in alleviating intestinal mucosal inflammation compared to uncoated probiotics.

• The nanocoated L. plantarum showed improved alleviation of intestinal mucosal inflammation.
• The treatment also restored gut barrier integrity.
• Microbial homeostasis was reestablished by the nanocoated bacteria.
• These improvements were attributed to the combination of the self-adaptive nanoarmor with the inherent anti-inflammatory properties of L. plantarum ST-III.

Nanocoated bacteria showed significant therapeutic potential in treating Parkinson's disease as a model for extraintestinal disorders.

• Treatment with nanocoated bacteria improved motor behavior disorders in the PD model.
• The nanocoated bacteria reduced dopaminergic neuronal death.
• Neuroimmune responses were mitigated by the treatment.
• Parkinson's disease was used as a model to demonstrate that intestinal bacteriotherapy can address extraintestinal disorders.

Intestinal localized inflammations are recognized as key contributors to the incidence and progression of diverse extraintestinal disorders, providing the rationale for intestinal probiotic colonization strategies.

• Probiotic colonization has been 'increasingly highlighted for its potential to modulate susceptibility and progression' of extraintestinal diseases.
• Multiple physiological and pathological characteristics in the intestine pose adhesion- and colonization-related challenges for probiotics.
• The gut-brain axis connection underlies the rationale for treating PD via intestinal intervention.

The nanoarmor approach proposes new insights into living therapeutics for the treatment of extraintestinal diseases by addressing the colonization barriers in the impaired intestinal microenvironment.

• The study combines microenvironment self-adaptive nanocoating with intrinsic probiotic anti-inflammatory properties.
• The approach addresses both the physical dynamic conditions of the intestine and the pathological microenvironment.
• The authors describe this as proposing 'new insights into the living therapeutics for the treatment of extraintestinal diseases.'