[Preliminary study on Aspergillus fumigatus-induced IKKα controlled maspin protein expression in respiratory epithelial cells of rats]
Fang Zhang1, Yun-fang An, Chang-qing Zhao
1Department of Otorhinolaryngology Head and Neck Surgery, Second Hospital of Shanxi Medical University, Taiyuan 030001, China.
Objective:
To study if the expression of maspin protein in respiratory epithelial cells was downregulated through IκB kinase-α (IKKα)-controlled mechanism in an Aspergillus fumigatus-induced model in rat.
Methods:
Inactivated Aspergillus fumigatus hyphae (AFH) suspension was used to induce respiratory epithelial cells (REC) cultured in vitro in rat, with PBS buffer as control. By RT-PCR, the mRNA expression of maspin was quantified, and by immunocytochemistry, the expression of maspin and IKKα in REC was observed. Furthermore AFH (from level 1 to level 3) suspension was prepared to induce REC. Then Western blot hybridization technique was used to detect the expression of maspin and IKKα protein. All data were processed by analysis of variance and two-variable correlation analysis.
Results:
By RT-PCR, a statistically significant (t = 2.463, P < 0.05) expression of maspin mRNA was found (0.128 ± 0.059 in AFH group, 2.972 ± 0.353 in control group). By Immunocytochemistry, the difference of maspin protein color in different groups was shown statistically significant in integrated scoring (t = 3.721, P < 0.05, weak positive in AFH group, moderately positive in control group). While in IKKα color study, the difference between the two groups was also statistically significant (t = 6.825, P < 0.05) in integrated scoring, with a moderate positive in AFH group and weak positive in control group. By Western Blot hybridization, grayscale ratio of maspin and β-actin was 0.912 ± 0.023 in control group, 0.607 ± 0.030, 0.476 ± 0.019, 0.416 ± 0.017 in AFH 1-3 groups, respectively, with a statistically significant difference within the four groups (F = 281.91, P < 0.05); While grayscale ratio of IKKα and β-actin was 0.624 ± 0.012 in control group, 0.739 ± 0.020, 0.778 ± 0.010, 0.927 ± 0.017, respectively, in AFH 1-3 groups; with a statistically significant difference within the four groups(F = 200.91, P < 0.05). Moreover, the difference between any two groups from both AFH group (including subgroup 1, 2 and 3) and control group was statistically significant. Two-variable correlation analysis indicated a negative correlation between expression of maspin and IKKα (r = -0.911, P < 0.05).
Conclusions:
Induced by Aspergillus fumigatus, the rat respiratory epithelia might upregulate the expression of IKKα with a downregulated expression of maspin protein.
Insights
Aspergillus fumigatus infection downregulates maspin protein expression in rat respiratory epithelial cells, potentially via upregulation of IκB kinase-α (IKKα). This study investigates the molecular mechanism behind this fungal-induced respiratory response.
Area of Science:
- Respiratory Medicine
- Molecular Biology
- Mycology
Background:
- Investigates the role of maspin protein in respiratory epithelial cells (REC).
- Examines the impact of Aspergillus fumigatus (AF) infection on REC.
- Focuses on the potential involvement of IκB kinase-α (IKKα) in regulating maspin expression.
Purpose of the Study:
- To determine if Aspergillus fumigatus downregulates maspin protein expression in rat REC.
- To elucidate the potential mechanism involving IκB kinase-α (IKKα) in this downregulation.
- To analyze the correlation between maspin and IKKα expression levels.
Main Methods:
- Establishment of an in vitro rat REC model induced by inactivated Aspergillus fumigatus hyphae (AFH).
- Quantification of maspin mRNA using RT-PCR.
- Observation of maspin and IKKα protein expression via immunocytochemistry and Western blot hybridization.
- Statistical analysis including ANOVA and two-variable correlation.
Main Results:
- Significant downregulation of maspin mRNA and protein expression in AFH-induced REC compared to controls.
- Significant upregulation of IKKα protein expression in AFH-induced REC.
- A statistically significant negative correlation (r = -0.911, P < 0.05) was observed between maspin and IKKα expression.
Conclusions:
- Aspergillus fumigatus infection induces a downregulation of maspin protein expression in rat respiratory epithelial cells.
- The observed downregulation of maspin is potentially mediated by an upregulation of IKKα.
- These findings suggest a novel molecular mechanism in fungal-induced respiratory inflammation.
