Fig 2: DHA reduced collagen deposition in pulmonary fibrosis tissues and inhibited the expression of Tgfb1, Jak2, and Stat3 mRNA in lung tissues. The rats were sacrificed at 28 days after bleomycin injection, with or without DHA treatment, their lungs were removed and blood collected. (A) Representative images of Masson staining of bleomycin-treated rat lungs, with and without DHA treatment. (B) Evaluation of pulmonary fibrosis using the Ashcroft score (n = 6). (C) Determination of hydroxyproline in lung tissue (n = 6). (D) Tgfb1, (E) Jak2, and (F) Stat3 mRNA levels in lung tissues were determined using qRT-PCR (n = 6), data are expressed as fold change in mRNA expression normalized to Gapdh expression, with respect to the control group. *P < 0.05, **P < 0.001. Abbreviations: BLM: bleomycin; DHA-1: dihydroartemisinin 25 mg/kg/d; DHA-2: dihydroartemisinin 50 mg/kg/d; DHA-3: dihydroartemisinin 100 mg/kg/d; NS: not statistically significant; qRT-PCR: quantitative real-time reverse transcription PCR.

Fig 3: DHA inhibited the JAK2/STAT3 pathway in pneumonia tissue. (A) Tgfb1, (B) Jak2, and (C) Stat3 mRNA levels in the lungs were determined using qRT-PCR (n = 6), data are expressed as the fold change in mRNA expression normalized to Gapdh expression, with respect to the control group. Representative images of (D) TGF-ß1 and (E) JAK2 protein expression in lung tissue detected using IHC. Mean IOD of (F) TGFß1 and (G) JAK2 protein by IHC staining. Data are expressed as the means ± standard error. *P < 0.05, **P < 0.001. Abbreviations: BLM: bleomycin; DHA-1: dihydroartemisinin 25 mg/kg/d; DHA-2: dihydroartemisinin 50 mg/kg/d; DHA-3: dihydroartemisinin 100 mg/kg/d; IHC: immunohistochemistry; IOD: integrated optical density; NS: not statistically significant.