[Therapeutic effects of histone deacetylase inhibitor givinostat on air inflammation and high airway resistance in a murine asthma model].

Objective: To investigate the therapeutic effects of givinostat, a histone deacetylase inhibitor (HDACI), on the development of chronic asthma with airway inflammation, airway remodeling and airway hyperresponsiveness (AHR). Methods: BALB/C mice were randomly divided into control group, asthma group, dexamethasone group and givinostat group (n=12 per group). AHR was assessed. Total cell numbers and differential counts, interleukin-4(IL-4), interleukin-5(IL-5) and interferon-γ (IFNγ) levels in the bronchoalveolar lavage fluid (BALF) were measured in the above 4 groups. The pathology of lung tissue was evaluated. Immunohistochemical (IHC) staining and Western blot were used to detect α smooth muscle actin(α-SMA) and transforming growth factor-β1(TGFβ1). Results: Compared with the asthma only group, givinostat treatment relieved airway resistance (2.96±1.01 vs 6.50±0.79, P<0.05). Total inflammatory cells [(33.04±5.62)×10(4)/ml vs (98.04±9.27)×10(4)/ml, P<0.01], eosinophil cells [(9.17±2.33)×10(4)/ml vs(37.64±6.98)×10(4)/ml, P<0.01], IL-4 [(10.12±2.98)ng/ml vs (16.88±2.78)ng/ml, P<0.05] and IL-5 [(27.09±3.62)ng/ml vs (37.86±7.34)ng/ml, P<0.05] levels were all reduced in givinostat group, while IFNγ [(91.86±23.73)pg/ml vs (60.49±11.88)pg/ml, P>0.05] was enhanced in BALF. Inflammatory cell infiltration around the airway was reduced, with decreased inflammatory cell score[(1.60±0.69)points vs (3.40±0.68) points, P<0.01] and inflammatory cell number (111.65±31.41 vs 601.25±186.85, P<0.01). The goblet cell metaplasia [(26.36±2.33)% vs (57.21±11.56)%] and collagen deposition area [(52.77±7.58)μm(2)/μm vs (111.81±12.40)μm(2)/μm] were obviously reduced (P<0.01). The expressions of α-SMA and TGFβ1 in the lung tissue were both significantly decreased (P<0.01). Conclusion: Givinostat treatment can reduce airway inflammation, airway remodeling and airway hyperresponsiveness in chronic asthma. Its effect is comparable to that of glucocorticoid hormone treatment.