[Use of antifibrotic drugs in interstitial lung disease]. / Einsatz antifibrotischer Medikamente bei interstitiellen Lungenerkrankungen.

The interstitial lung diseases ILDs are a heterogeneous group of diseases that often lead to progressive fibrosis of the lungs with corresponding functional impairment. With nintedanib, a tyrosinkinase inhibitor and angiokinase inhibitor, as well as pirfenidone, which unfolds its effect among other things by inhibiting the transforming growth factor ß, there are currently 2 approved antifibrotic drugs. In the rapidly progressing idiopathic pulmonary fibrosis IPF, the antifibrotic drugs nintedanib and pirfenidone have been established and approved in therapy for several years. The initiation of antifibrotic therapy should be carried out early after diagnosis by multidisciplinary discussion (MDD). In systemic scleroderma with lung involvement nintedanib should be used in the case of relevant fibrosis in addition to immunosuppressive therapy. Recently, nintedanib has also become a new option for the treatment of progressive fibrosing ILDs (PF-ILDs). This describes the course of various disease entities such as connective tissue disease associated ILDs (CTD-ILDs), fibrosing hypersensitivity pneumonitis or fibrosing courses of non-IPF idiopathic interstitial pneumonitis (non-IPF IIPs) that have a corresponding fibrose-related worsening of respiratory symptoms, a deterioration of lung-functioning parameters or a disease progression in CT. Although pirfenidone also shows positive signals for this group of patients in some selected studies, its use in PF-ILD is not yet recommended. In particular, gastrointestinal side effects can occur under therapy with antifibrotic drugs and require a long-term close interdisciplinary connection of patients.

AMPK Dilates Resistance Arteries via Activation of SERCA and BKCa Channels in Smooth Muscle.

The protective effects of 5'-AMP-activated protein kinase (AMPK) on the metabolic syndrome may include direct effects on resistance artery vasomotor function. However, the precise actions of AMPK on microvessels and their potential interaction are largely unknown. Thus, we set to determine the effects of AMPK activation on vascular smooth muscle tone and the underlying mechanisms. Resistance arteries isolated from hamster and mouse exhibited a pronounced endothelium-independent dilation on direct pharmacological AMPK activation by 2 structurally unrelated compounds (PT1 and A769662). The dilation was associated with a decrease of intracellular-free calcium [Ca(2+)]i in vascular smooth muscle cell. AMPK stimulation induced activation of BKCa channels as assessed by patch clamp studies in freshly isolated hamster vascular smooth muscle cell and confirmed by direct proof of membrane hyperpolarization in intact arteries. The BKCa channel blocker iberiotoxin abolished the hyperpolarization but only partially reduced the dilation and did not affect the decrease of [Ca(2+)]i. By contrast, the sarcoplasmic/endoplasmic Ca(2+)-ATPase (SERCA) inhibitor thapsigargin largely reduced these effects, whereas combined inhibition of SERCA and BKCa channels virtually abolished them. AMPK stimulation significantly increased the phosphorylation of the SERCA modulator phospholamban at the regulatory T17 site. Stimulation of smooth muscle AMPK represents a new, potent vasodilator mechanism in resistance vessels. AMPK directly relaxes vascular smooth muscle cell by a decrease of [Ca(2+)]i. This is achieved by calcium sequestration via SERCA activation, as well as activation of BKCa channels. There is in part a mutual compensation of both calcium-lowering mechanisms. However, SERCA activation which involves an AMPK-dependent phosphorylation of phospholamban is the predominant mechanism in resistance vessels.