5-ASA-loaded SiO2 nanoparticles-a novel drug delivery system targeting therapy on ulcerative colitis in mice.

The targeting of 5-aminosalicylic acid (5-ASA), a first-line therapeutic agent for mild to moderate active ulcerative colitis (UC), to the site of inflammation has remained a challenge and an unmet requirement in the treatment of UC. However, nanoscale carriers for targeted drug delivery are promising for pharmacotherapy, and nanoparticles improve the pharmacokinetics of the loaded therapeutics based on their physical properties. To design and prepare 5­ASA­loaded silicon dioxide nanoparticles (5­ASA­SiO2 NPs), a micro­emulsion method was conducted, and their respective therapeutic effects were validated in a mouse model of UC. Cytotoxicity of 5­ASA­SiO2 NPs was detected in vitro using the Cell Counting Kit­8 method. The therapeutic effect of 5­ASA­SiO2 NPs was assessed based on their disease activity index (DAI), colon histopathology, myeloperoxidase (MPO) and levels of tumor necrosis factor­α (TNF­α) and interleukin­6 (IL­6). SiO2 NPs were successfully prepared, and cytotoxicity of 5­ASA­SiO2 NPs was identified as being similar to 5­ASA and SiO2 NPs. DAI and colonic histopathology scores in the normal dosage, high dosage and the 5­ASA­SiO2 NP groups demonstrated a significant improvement when compared with the model group. DAI in the high dosage and 5­ASA­SiO2 NP groups also demonstrated a significant improvement when compared with the normal dosage group. However, MPO, serum IL­6 and TNF­α levels in normal dosage, high dosage and 5­ASA­SiO2 NPs groups were significantly lower than in the model group, and these indexes in the high dosage group and 5­ASA­SiO2 NP group were significantly lower than that in the normal dosage group. Expression of IL­6 and TNF­α mRNA in colonic mucosa in the normal dosage, high dosage and 5­ASA­SiO2 NP group was significantly lower than that in the model group. Colonic mucosal IL­6 and TNF­α mRNA expression in the high dosage and 5­ASA­SiO2 NP groups was significantly lower than that in the normal dosage group (P<0.05). In conclusion, 5­ASA­SiO2 NPs are a selective drug release system that target the inflamed colon, characteristics of UC, and can greatly increase therapeutic efficacy in UC.

Salidroside protects against bleomycin-induced pulmonary fibrosis: activation of Nrf2-antioxidant signaling, and inhibition of NF-κB and TGF-ß1/Smad-2/-3 pathways.

Pulmonary fibrosis (PF) can severely disrupt lung function, leading to fatal consequences. Salidroside is a principal active ingredient of Rhodiola rosea and has recently been reported to protect against lung injures. The present study was aimed at exploring its therapeutic effects on PF. Lung fibrotic injuries were induced in SD rats by a single intratracheal instillation of 5 mg/kg bleomycin (BLM). Then, these rats were administrated with 50, 100, or 200 mg/kg salidroside for 28 days. BLM-triggered structure distortion, collagen overproduction, excessive inflammatory infiltration, and pro-inflammatory cytokine release, and oxidative stress damages in lung tissues were attenuated by salidroside in a dose-dependent manner. Furthermore, salidroside was noted to inhibit IκBα phosphorylation and nuclear factor kappa B (NF-κB) p65 nuclear accumulation while activating Nrf2-antioxidant signaling in BLM-treated lungs. Downregulation of E-cadherin and upregulation of vimentin, fibronectin, and α-smooth muscle actin (α-SMA) indicated an epithelial-mesenchymal transition (EMT)-like shift in BLM-treated lungs. These changes were suppressed by salidroside. The expression of TGF-ß1 and the phosphorylation of its downstream targets, Smad-2/-3, were enhanced by BLM, but weakened by salidroside. Additionally, salidroside was capable of reversing the recombinant TGF-ß1-induced EMT-like changes in alveolar epithelial cells in vitro. Our study reveals that salidroside's protective effects against fibrotic lung injuries are correlated to its anti-inflammatory, antioxidative, and antifibrotic properties.

Glycyrrhizic acid alleviates bleomycin-induced pulmonary fibrosis in rats.

Idiopathic pulmonary fibrosis is a progressive and lethal form of interstitial lung disease that lacks effective therapies at present. Glycyrrhizic acid (GA), a natural compound extracted from a traditional Chinese herbal medicine Glycyrrhiza glabra, was recently reported to benefit lung injury and liver fibrosis in animal models, yet whether GA has a therapeutic effect on pulmonary fibrosis is unknown. In this study, we investigated the potential therapeutic effect of GA on pulmonary fibrosis in a rat model with bleomycin (BLM)-induced pulmonary fibrosis. The results indicated that GA treatment remarkably ameliorated BLM-induced pulmonary fibrosis and attenuated BLM-induced inflammation, oxidative stress, epithelial-mesenchymal transition, and activation of transforming growth factor-beta signaling pathway in the lungs. Further, we demonstrated that GA treatment inhibited proliferation of 3T6 fibroblast cells, induced cell cycle arrest and promoted apoptosis in vitro, implying that GA-mediated suppression of fibroproliferation may contribute to the anti-fibrotic effect against BLM-induced pulmonary fibrosis. In summary, our study suggests a therapeutic potential of GA in the treatment of pulmonary fibrosis.

Influence of Rosiglitazone on the Expression of PPARγ, NF-κB, and TNF-α in Rat Model of Ulcerative Colitis.

Aim. To observe the disease activity index (DAI) and the colonic mucosa damage index (CMDI), detect the colonic mucosal expression of PPARγ, NF-κB, and TNF-α in rats with ulcerative colitis (UC), and to investigate the protective role of rosiglitazone in UC. Methods. Sprague-Dawley (SD) rats were divided into three groups: a control group, a rosiglitazone treatment group, and a UC model group. Rats were sacrificed on days 7, 14, 21, or 35 following administration of treatment after enema and DAI, CMDI and colonic expression of PPARγ, NF-κB, and TNF-α were assessed. Results. In the UC model group, DAI, CDMI and the colonic expression of NF-κB and TNF-α increased significantly compared to the control group at all timepoints, but PPARγ decreased significantly. Furthermore, in the rosiglitazone treatment group, DAI and CMDI decreased significantly on the 14-day, 21-day, and 35-day timepoints compared to the UC model group; the colonic expression of NF-κB and TNF-α decreased compared to UC model group at all timepoints, but the PPARγ expression increased significantly. Conclusions. Rosiglitazone can alleviate colonic mucosal inflammation and have the protective role on UC by upregulating PPARγ expression and downregulating NF-κB and TNF-α expression.

Effect of Etiasa on the expression of matrix metalloproteinase-2 and tumor necrosis factor-α in a rat model of ulcerative colitis.

The aim of this study was to determine the disease activity index (DAI) and the colonic mucosa damage index (CMDI), and to detect the colonic mucosal expression levels of matrix metalloproteinase-2 (MMP-2) and tumor necrosis factor-α (TNF-α) in rats with ulcerative colitis (UC). We also aimed to investigate the protective role of Etiasa in UC. Sprague Dawley (SD) rats were randomly divided into three groups: the control, an Etiasa-treated group and a UC model group. Rats were sacrificed on days 14, 21, 35 or 56 following the administration of treatment by enema and the DAI, CMDI and colonic expression levels of MMP-2 and TNF-α were assessed. In the UC model group, the DAI and CDMI scores and the colonic expression levels of MMP-2 and TNF-α increased significantly compared with the control at all timepoints, and were also significantly higher than those in the Etiasa-treated group. In conclusion, the expression levels of MMP-2 and TNF-α increased significantly in rats with UC. Etiasa reduces colonic mucosal damage by downregulating the expression of MMP-2 and TNF-α.

Protective role of metalloproteinase inhibitor (AE-941) on ulcerative colitis in rats.

AIM: To evaluate the protective role of AE-941, a matrix metalloproteinase (MMP) inhibitor, on ulcerative colitis (UC) in rats. METHODS: Sprague Dawley (SD) rats were randomly divided into three groups: a control group, an AE-941 treatment group, and an UC model group. Rats were sacrificed on days 7, 21, or 56 following administration of treatment by enema and the disease activity index (DAI), colonic mucosa damage index (CMDI) and colonic expression of MMP-2 and MMP-9 were assessed. RESULTS: DAI and CDMI scores in the UC model group increased significantly compared to the control group at all timepoints (P < 0.001), and also increased significantly at the 21- and 56-d timepoints compared to the AE-941-treated group (DAI: 21- and 56-d = 2.09 ± 0.25, 1.52 ± 0.30 vs 1.55 ± 0.28, 0.59 ± 0.19, respectively, P = 0.040 and 0.007, CMDI: 21- and 56-d = 3.03 ± 0.42, 1.60 ± 0.35 vs 2.08 ± 0.46, 0.86 ± 0.37, respectively, P = 0.040 and 0.005). Furthermore, the colonic expression of MMP-2 and MMP-9 in the UC model group increased significantly compared to the control group (P < 0.001), and also increased compared to the AE-941-treated group on the 21- and 56-d timepoints (MMP-2: 21- and 56-d = 0.6048 ± 0.0522, 0.4163 ± 0.0330 vs 0.3983 ± 0.0218, 0.1093 ± 0.0072, respectively, P = 0.010; MMP-9: 21- and 56-d = 0.6873 ± 0.0472, 0.4328 ± 0.0257 vs 0.5179 ± 0.0305, 0.2673 ± 0.0210, respectively, P = 0.010 and 0.040). CONCLUSION: Expression of MMP-2 and MMP-9 increased significantly in rats with UC. AE-941 can reduce colonic mucosal damage by downregulating the expression of MMP-2 and MMP-9.