L'inflammation pulmonaire dans la mucoviscidose

[Therapeutic advances in cystic fibrosis in 2014]

Twenty-five years after the cystic fibrosis (CF) gene identification, this discovery actually begins to benefit to patients. Increasing our knowledge on CFTR biology, as well as technical progress made in order to screen for new drugs have made therapeutic strategies move an important step forward. It is likely that in the forthcoming years, the panel of molecules available for CF patients will be larger, with new activators and potentiators. The disease by itself may consequently change in its natural history. CF is an example of the so-called personalized medicine, aiming to fit treatment according to patient's genetic background. Ongoing clinical trials may enlarge the actually limited eligible number of CF patients for new drugs such as ivacaftor. Beyond this exciting and promising new therapeutic approach, one may not push symptomatic treatments on the side. Improvements have been made for inhaled antibiotics administration, aiming to simplify patient's life; clinical trials using new molecules able to liquefy mucus or with anti-inflammatory properties are actually underway. One important next step in the care for CF will be to design and conduct early intervention trials in CF infants. Newborn screening program have been widely implanted around the word, and cohorts studies have shown that both functional and structural abnormalities occurred very early, making the therapeutic window of opportunity tight.

Effects of lettuce glycoside B in ameliorating pulmonary fibrosis induced by irradiation exposure and its anti-oxidative stress mechanism

The present research assessed the effects of lettuce glycoside B (LGB), a compound separated and purified from Pterocypsela laciniata, on irradiation-induced pulmonary fibrosis and explored the mechanism involved. Animal model of irradiation exposure inducing pulmonary fibrosis was established by Co irradiator. Rats were intraperitoneally treated with LGB (100, 200 and 400 mg/kg) once per day for a month. Lung index data were analyzed. The levels of fibrosis were assessed by hydroxyproline (Hyp) of pulmonary and lung tissue sections after irradiation exposure. Alveolitis and fibrosis levels were calculated from semi-quantitative analysis of hematoxylin and eosin and Masson's trichrome lung section staining. The serum levels of transforming growth factor β1 (TGF-β1), interleukin (IL)-6, and tumor necrosis factor-α (TNF-α) were also evaluated. Antioxidant enzymes of superoxide dismutase (SOD) were measured in serum. Moreover, we also measured serum malondialdehyde (MDA) levels, a marker of oxidative stress. Treatment with LGB significantly reduced mortality rates and lung index scores and MDA content, enhanced SOD and other antioxidant enzymes activity, and regulated serum levels of TGF-β1, IL-6, and TNF-α. These results demonstrated that LGB significantly inhibited irradiation-induced pulmonary fibrosis. Furthermore, the results suggested promising clinical effect of LGB therapies for treating irradiation-induced pulmonary fibrosis.

[Therapeutic update in cystic fibrosis]

We present the recent therapeutic advances in the cystic fibrosis care. It concerns improvements in symptomatic treatment with the development of dry powder inhaled antibiotics that improved quality of life, and innovative treatments namely the modulators of the cystic fibrosis transmembrane protein conductance regulator (CFTR), molecules which act specifically at the level of the defective mechanisms implied in the disease. The life expectancy of cystic fibrosis patients born after 2000, is estimated now to be about 50 years. This improvement of survival was obtained with the organization of the care within the specialized centers for cystic fibrosis (Centre de ressource et de compétences de la mucoviscidose) and remains still based on heavy symptomatic treatments. Dry powder inhaled antibiotics constitute a significant time saving for patients to whom all the care can achieve two hours daily. Since 2012, the modulators of CFTR, molecules allowing a pharmacological approach targeted according to the type of the mutations, allows a more specific approach of the disease. Ivacaftor (Kalydeco(®)) which potentialises the function of the CFTR protein expressed on the cellular surface is now available for patients with the G551D mutation. Lumacaftor is going to be tested in association with ivacaftor in patients with the F508del mutation, that is present in at least 75% of the patients. The ataluren which allows the production of a functional protein CFTR in patients with a no sense mutation is the third representing of this new therapeutic class. We presently have numerous symptomatic treatments for the cystic fibrosis care. The development of CFTR modulators, today available to a restricted number of patients treated with ivacaftor represents a very promising therapeutic avenue. It will represent probably the first step to a personalized treatment according to CFTR genotype.