Hypothesis / aims of study
Cystic fibrosis is a difficult problem in the treatment of urinary system diseases. It is easy to cause the changes of bladder morphology and structure, and then affect the function, and even cause the damage of kidney, ureter and other tissues.At present, the main mechanisms of bladder fibrosis are: promoting the transformation of bladder epithelial cells into stromal cells and secreting extracellular matrix;It induces the activation of fibroblasts in the bladder and promotes the synthesis of collagen.Bladder vascular development abnormalities and dysfunction, resulting in bladder ischemia, hypoxia, interstitial cell proliferation, extracellular matrix accumulation, and then cause fibrosis;The infiltration of inflammatory cells and cytokines in the bladder tissue causes the proliferation and secretion of collagen fibers.Cystic fibrosis is one of the difficult problems in the treatment of urinary system diseases.Currently, there is no effective treatment for fibrosis or reversal.Study found bladder fibrosis and inflammation of the bladder, bladder pressure and bladder blood supply and so on are all in relationships, this article design with cell inflammatory factors inducing stimuli hb - SMCs, observe the NF-KB, iNOS and Collagen Ⅲ expression changes.Inducible nitric oxide synthase (iNOS) is a class of catalytic enzyme molecules that play a regulatory role in the development of many diseases including bladder fibrosis. To investigate the effects of cytokines interleukin-1 α (IL-1 α), interleukin-1 β (IL-1 β), interferon- γ (IFN- γ) on bladder fibrosis induced by iNOS in human bladder smooth muscle cells （hb-SMCs）.
Study design, materials and methods
Hb-SMCs cultured in 5 ~ 7 passages was used in the experiment and was randomly divided into cytokine intervention group, that is, the experimental group (IFN- γ: 100ng/ml; IL-1α: 20ng/ml;IL-1β: 20 ng/ml) and the blank control group. After the two groups cells was cultured in vitro for 2 days, the expression of NF-κB p65、iNOS and Collagen Ⅲ mRNA in hb-SMCs was detected by Q-PCR ,and the expression of NF-κB p65、iNOS and Collagen Ⅲ protein in hb-SMCs was detected by fluorescence immunoassay and Western Blot.
Experimental data show that:the expression of NF-κB p65、iNOS and Collagen Ⅲ protein and mRNA in hb-SMCs of experimental group was significantly higher than that in the control group. Here are the preliminary conclusions:(1) inflammatory factors produced by urinary tract infection may be one of the starting points for inducing bladder fibrosis.(2) cell inflammatory factor IL - 1 alpha, beta, and IFN - IL - 1 gamma may by activating the nf-kappa B, start the iNOS transcription induced expression of Collagen III, promote the bladder fibrosis, this may be one of the mechanism of its development.(3) patients with neurogenic bladder are prone to urinary tract infection, and long-term infiltration of cytokines may be one of the causes of bladder function deterioration and symptom aggravation in NB patients.
Interpretation of results
Fibrosis is a diverse disease in which every organ in the body can be affected by a fibrotic response, which consists of multisystem diseases such as systemic sclerosis and fibrotic reactions affecting individual organs, including pulmonary, kidney, liver, heart and bladder fibrosis.It is widely believed to be related to specific cell types with unique characteristics, and understanding the cellular and molecular mechanisms responsible for the generation of such cells and the initiation of key signaling cascages are crucial for the development of therapies.However, due to the diversity and complexity of fibrosis diseases and the interaction of multiple signal transduction pathways, more than one drug may need to be administered simultaneously in drug treatment. Currently, there is no completely effective method to treat fibrosis.The effect of cytokine on the expression of iNOS、NF-κB p65 and Collagen III in hb-SMCs may be one of the mechanisms of urinary inflammation in the development of bladder fibrosis.
Urinary tract infection may induce the NF-κB p65 expression, activation induced iNOS and Collagen III of expression, promote the bladder fibrosis.This may be one of the mechanisms of inflammation in the development of cystic fibrosis.Therefore, in patients with NB, urinary tract infection due to long-term catheterization and retention of urine is likely to accelerate the deterioration of bladder function.But as a result of this study is simple in vitro cell model of the inflammatory reaction, also can not completely represent the body physiological conditions sticklebacks, inflammation, inflammatory cytokines and iNOS, NF-κB p65, Collagen III complex mechanisms, the next step we have yet to animal experiments and applications targeted inhibitors to further research.