Effect of new photosensitizer compound LD 4 photodynamic therapy on ulcerative colitis rats
10.3760/cma.j.cn121382-20231107-00606
- VernacularTitle:新型光敏剂化合物LD 4光动力疗法对溃疡性结肠炎大鼠的治疗作用研究
- Author:
Yumei RONG
1
;
Ge HONG
;
Tianjun LIU
Author Information
1. 天津市第三中心医院，天津市重症疾病体外生命支持重点实验室，天津市人工细胞工程技术研究中心，天津市肝胆疾病研究所，天津 300170
- Keywords:
Ulcerative colitis;
Photodynamic therapy;
Inflammatory factor;
Oxidative stress
- From:
International Journal of Biomedical Engineering
2023;46(6):514-520
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the therapeutic effects of photodynamic therapy (PDT) on a rat model of ulcerative colitis (UC) induced by Escherichia coli. Methods:Each rat was administered 1 ml of 1×10 9 enteric invasive E. coli to establish an UC model. Thirty-six Sprague Dawley rats were randomly divided into control, model, low-dose LD 4-PDT, medium-dose LD 4-PDT, high-dose LD 4-PDT (60, 120, 240 μg/kg), and levofloxacin (LEV) (100 mg/kg) groups, with six rats in each group. The UC model was established in all groups except the control group, which received 0.9% sodium chloride injection once. The first day of E. coli administration was recorded as day 0, and treatment was initiated on day 7 with LD 4 enema, levofloxacin gavage, and alternating enema/gavage for a total of four times. After a 30-minute exposure to each dose, the colon was irradiated using a 650 nm laser PDT system with an energy density of 25 J/cm 2, while the LEV group was not irradiated. The levels of body mass, colon length, intestinal pathological tissue, inflammatory factors interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), oxidative stress factors myeloperoxidase (MPO), glutathione (GSH), and superoxide dismutase (SOD) were compared among all groups. Results:The body mass and colon length of the model group were lower than those of the control group. The body mass and colon length of the low, medium, and high -dose LD 4-PDT groups and LEV group were higher than those of the model group. Compared to the control group, the model group exhibited more epithelial cell loss, multiple ulcers, infiltration of inflammatory cells into the mucosa and submucosa, and decreased goblet cells. In contrast, the surface mucosa of colon tissue recovered, goblet cells increased, and ulcer healing was good in the low, medium, and high-dose LD 4-PDT groups and LEV group compared to the model group. Compared to the control group, the levels of TNF-α, IL-6, and MPO inflammatory factors were significantly increased in the model group ( all P < 0.001). Compared to the model group, the levels of TNF-α, IL-6, and MPO inflammatory factors in colon tissue from the low, medium, and high -dose LD 4-PDT groups and LEV group were significantly decreased ( P < 0.05, P < 0.001). Compared to the control group, MDA levels were increased, while GSH and SOD levels were decreased in the model group. In contrast, MDA levels in the low, medium, and high-dose LD 4-PDT groups were decreased ( P < 0.05, P < 0.001), while GSH and SOD levels were increased compared to the model group. Conclusions:Low-dose LD 4-PDT promotes the healing of colon mucosa, alleviates inflammation, regulates oxidative stress, and improves symptoms of UC.
