Diagnostik des trockenen Auges

[What is Important in Diagnosing Dry Eye Disease - Recommendations According to current Guidelines (DEWS II, DOG/BVA)]

Dry Eye is one of the most common ocular diseases worldwide with an increasing number of patients. The pathogenesis of this disease is multifactorial and complex and the basis for diagnostic strategies and therapies. The current definition of dry eye disease as described in DEWS II includes inflammatory mechanisms at the ocular surface, a loss of homeostasis, hyperosmolarity of the tear film and neurosensory abnormalities. Subject symptom scores, a detailed patient history, certain diagnostic tools, and interdisciplinary interactions are necessary to enable an efficient, individualized and successful therapy. Important diagnostics include risk factor analysis, slit lamp examination, tear secretion tests, tearfilm stability tests, and tests for measuring the ocular surface inflammation.

Was ist bei der Diagnostik des Trockenen Auges zu beachten?

Die komplexe, multifaktorielle Erkrankung „Trockenes Auge“ erfordert für die Diagnostik mehr als ein einziges Testverfahren inklusive einer subjektiven Fragebogenerhebung. Zudem kam es in den letzten Jahren zu einem Paradigmenwechsel im Verständnis dieser Erkrankung. Dieser erforderte Änderungen in Definition und diagnostischen Strategien und zog die Aktualisierung nationaler und internationaler Leitlinien (DOG/BVA und DEWS II) nach sich.

L-carnitine suppresses transient receptor potential vanilloid type 1 activity and myofibroblast transdifferentiation in human corneal keratocytes

Corneal stromal wound healing is a well-balanced process promoted by overlapping phases including keratocyte proliferation, inflammatory-related events, and tissue remodeling. L-carnitine as a natural antioxidant has shown potential to reduce stromal fibrosis, yet the underlying pathway is still unknown. Since transient receptor potential vanilloid 1 (TRPV1) is a potential drug target for improving the outcome of inflammatory/fibrogenic wound healing, we investigated if L-carnitine can mediate inhibition of the fibrotic response through suppression of TRPV1 activation in human corneal keratocytes (HCK). We determined TRPV1-induced intracellular calcium transients using fluorescence calcium imaging, channel currents by planar patch-clamping, and cell migration by scratch assay for wound healing. The potential L-carnitine effect on TRPV1-induced myofibroblast transdifferentiation was evaluated by immunocytochemical detection of alpha smooth muscle actin. RT-PCR analysis confirmed TRPV1 mRNA expression in HCK. L-carnitine (1 mmol/l) inhibited either capsaicin (CAP) (10 µmol/l), hypertonic stress (450 mOsmol/l), or thermal increase (>43 °C) induced Ca2+ transients and corresponding increases in TRPV1-induced inward and outward whole-cell currents. This was accompanied by suppression of injury-induced increases in myofibroblast transdifferentiation and cell migration. In conclusion, L-carnitine contributes to inhibit stromal scarring through suppressing an injury-induced intrinsic TRPV1 activity that is linked with induction of myofibroblast transdifferentiation in HCK cells.