Intraperitoneal Phosphate-buffered Saline Research Articles

Effects of simvastatin on bleomycin-induced pulmonary fibrosis in female rats

Statins reduce cholesterol levels by inhibiting 3-hydroxy-3-methylglutaryl coenzyme A reductase and have a major place in the treatment of atherosclerotic disease. Recent studies have shown anti-inflammatory properties of statins. The purpose of this study was to evaluate the anti-inflammatory effect of simvastatin on bleomycin (BLM)-induced pulmonary fibrosis in rats. A total of 31 female Sprague-Dawley rats were divided into four groups: (1) intratracheal (IT) phosphate-buffered saline (PBS) + intraperitoneal (IP) PBS (n=7); (2) IT BLM + IP PBS (n=8); (3) IT BLM + low dose (LD) simvastatin (1 mg/kg daily, n=8); (4) IT BLM + high dose (HD) simvastatin (5 mg/kg daily, n=8). Simvastatin was administered IP for 15 days, beginning 1 day prior to IT BLM. The effect of simvastatin on pulmonary fibrosis was studied by measurements of IL-13, PDGF, IFN-γ, TGF-p1 levels in bronchoalveolar lavage (BAL) fluid and lung tissue hydroxyproline (HPL) content and by histopathological examination (Ashcroft score). BLM caused significant change in BAL fluid cytokine levels and increased both HPL content and histopathological score (p<0.001 for all). While LD simvastatin had no effect on cytokine levels, HD significantly reduced IL-13 (15.12 ±7.08 pg/ml vs. 4.43±2.34 pg/mL; p<0.05) and TGF-β1 levels (269.25 ±65.42 pg/mL vs. 131.75±32.65 pg/mL; p<0.05). Neither HD nor LD simvastatin attenuated HPL content or Ashcroft score. In conclusion, this study showed that LD simvastatin had no effect on a BLM-induced pulmonary fibrosis model, while the high dose caused partial improvement in profibrotic cytokine levels.

Altered expression of tissue remodeling genes in a mouse model of acute allergic rhinitis

Osteogenesis, fibrosis, and scarring are prominent pathologic changes resulting from chronic sinonasal inflammation, and these tissue changes may increase the degree of disease symptomatology and the level of surgical difficulty. Members of the bone morphogenetic protein (BMP) and fibroblast growth factor (FGF) families of cytokines and the matrix metalloproteinase (MMP) family of endopeptidases are known to regulate tissue remodeling in other disease processes, but their role in acute and chronic sinonasal inflammation remains undefined. A previously described mouse model of acute allergic rhinitis secondary to Aspergillus fumigatis exposure in BALB/C mice was used. Intranasal challenge was performed 1 week following intraperitoneal sensitization with A. fumigatis extract and mice were sacrificed 6 hours (n = 8) and 24 hours (n = 8) later. Additional mice were intranasally challenged 3 times per week and sacrificed at the end of 7 days (n = 8) and 21 days (n = 8). The snouts were processed for quantitative reverse-transcription polymerase chain reaction (RT-PCR) and compared to untreated controls for messenger ribonucleic acid (mRNA) expression of BMP1, 2, 3, 4, 5, 6, 7, 8a, 8b, 9, 10, FGF1, 2, 3, 4, 5, 6, 7, 8, 10, and MMP1a, 2, 3, 7, 8, 9, 12, and 14. Additional 21-day-old mice were prepared for sinonasal histopathology. Control mice were treated with the same protocol, with intraperitoneal phosphate-buffered saline (PBS) and intranasal PBS substituted for A. fumigatis extract. Untreated mice were used for additional comparison. Compared to both the PBS-treated and untreated control groups, statistically significant (p < 0.05) upregulation of MMP8 was observed in the 6-hour time point. Significant downregulation of MMP8 was observed at 1 week. Significant upregulation of FGF3 was observed at 1 week (p < 0.05). BMP3 and BMP5 were significantly downregulated in the 1-week group (p < 0.05). The mice exhibited histologic sinonasal changes consistent with allergic inflammation. Intranasal exposure to A. fumigatis results in altered expression of several tissue remodeling cytokines at varying time points in the acute allergic rhinitis mouse model. These changes in cytokine regulation may subsequently contribute to sinonasal osteogenesis, scarring, and fibrosis as seen in chronic rhinosinusitis.

Ulinastatin Alone Does Not Reduce Caspase 3-mediated Apoptosis in Protease-positive Aeromonas hydrophilia-induced Sepsis

To evaluate the effect of ulinastatin, a protease inhibitor, on survival and apoptosis in protease-positive Aeromonas hydrophilia (PPAH)-induced sepsis. Thirty mice were randomly allocated to receive intraperitoneal injection of either phosphate buffered saline (PBS) (control mice, n = 10) or PPAH (PPAH mice, n = 20). After 30 minutes, control mice received an additional intraperitoneal PBS injection, 10 PPAH mice received intraperitoneal PBS injection (non-treated PPAH mice), and the remaining 10 PPAH mice received an intraperitoneal injection of ulinastatin (ulinastatin-treated PPAH mice). Survival at 24 hours was 100% in control mice, and 35% (p < 0.05) in PPAH mice; the survival rate in non-treated and ulinastatin-treated PPAH mice were 30% and 40% (p > 0.05), respectively. The thymus weight (mg) decreased significantly in PPAH mice (51.1 +/- 14.9) compared to control mice (69.7 +/- 14.4; p < 0.001); there was no difference between ulinastatin-treated (52 +/- 13.9; p > 0.05) and non-treated PPAH mice (50.4 +/- 16). The thymus gland cell count reduced significantly in PPAH mice (8.1 +/- 4.7 x 10(7)) compared to control mice (12.8 +/- 6.6 x 10(7); p < 0.01), and immunofluorescence analysis demonstrated that the reduced cells were mostly CD4+ CD8+, in contrast to the increase in CD4+ CD8- cells. There was no difference in cell count between ulinastatin-treated (8.7 +/- 4.9 x 10(7)) and non-treated PPAH mice (7.4 +/- 4.6 x 10(7); p > 0.05). Caspase 3-mediated apoptosis was not detectable in control mice in contrast to the pronounced manifestation in PPAH mice. PPAH-induced sepsis has a high mortality that is related to lymphocyte apoptosis. Ulinastatin alone does not significantly reduce caspase 3-mediated lymphocyte apoptosis.