Combined Ovalbumin/DSS Mouse Model Reveals Mutual Aggravation in Bronchial Asthma and Ulcerative Colitis
Background
Bronchial asthma (BA) and ulcerative colitis (UC) are chronic, immune-mediated inflammatory diseases affecting the airways and intestines, respectively. Clinical observations increasingly link these conditions, suggesting mutual aggravation when they coexist. However, the precise underlying mechanisms driving this comorbidity and the availability of suitable experimental models to investigate their bidirectional impact remain limited. This gap hinders the development of integrated therapeutic strategies for patients suffering from both inflammatory disorders.
Study Design
Researchers established a comorbid model using 40 specific-pathogen-free female C57BL/6 mice, divided into four groups: control, BA, UC, and comorbid BA-UC. Bronchial asthma was induced via intraperitoneal sensitization with ovalbumin (OVA) followed by repeated aerosolized OVA challenges. Ulcerative colitis was induced by intermittent administration of dextran sulfate sodium (DSS). The comorbid group received both protocols synchronously. Key endpoints included pulmonary function, airway hyperresponsiveness, Disease Activity Index (DAI), body weight, quality-of-life scores, colon length, and histopathological changes in lung and colon tissues.
Results
All disease groups (BA, UC, and comorbid BA-UC) exhibited significant abnormalities in pulmonary function parameters compared to controls.
The comorbid BA-UC group consistently showed the most pronounced decline in quality-of-life scores among all experimental groups, indicating severe systemic impact. Line graph analysis revealed significant differences in colon length shortening and body weight changes in the comorbid BA-UC group (P < 0.05). Specifically, colon shortening was significantly greater in the comorbid group than in the UC group alone (P < 0.05). Furthermore, inflammatory cell infiltration was significantly increased in both the BA and comorbid BA-UC groups compared with the UC group (P < 0.05), highlighting an exacerbated inflammatory response when both conditions coexisted.
Key Findings
- A novel comorbid mouse model for bronchial asthma and ulcerative colitis was successfully established.
- Comorbid BA-UC mice exhibited the most pronounced decline in quality-of-life scores.
- Colon shortening was significantly greater in comorbid BA-UC mice than in UC-only mice (P < 0.05).
- Inflammatory cell infiltration was significantly increased in comorbid BA-UC compared to UC-only mice (P < 0.05).
- All disease groups showed significant pulmonary function abnormalities compared to controls.
Why It Matters
This study successfully establishes a robust and reliable murine model for bronchial asthma and ulcerative colitis comorbidity, which is a critical step for future research. This model provides an essential platform to unravel the complex bidirectional interactions between airway and intestinal inflammation, identify shared pathogenic mechanisms, and test novel therapeutic interventions targeting both diseases simultaneously. It moves beyond single-disease models, offering a more clinically relevant system to investigate how systemic inflammation from one site influences another, potentially leading to integrated treatment strategies for patients with these challenging co-occurring conditions.
bronchial asthma
ulcerative colitis
comorbidity
inflammatory bowel disease
airway inflammation
intestinal inflammation