Thesis Type: Expertise In Medicine

Institution Of The Thesis: Bursa Uludağ University, Tıp Fakültesi, Temel Tıp Bilimleri, Turkey

Approval Date: 2018

Thesis Language: Turkish


Supervisor: Arzu Yılmaztepe Oral


Acne rosacea (AR) is a chronic inflammatory skin disease affecting the facial skin. The disease is characterized by flashing, facial erythema, inflammatory papules, pustules and telangiectatic lesions. It is most commonly involved in the face region, rarely in the scalp, behind the ear, neck region. Pathophysiology is not entirely clear, as there are many triggering mechanisms, including genetic and environmental factors (such as heat, ultraviolet, spice, alcohol, stress), infectious causes, and the immune system.

The indolamine 2,3-dioxygenase (IDO) is a cytosolic, biosynthetic enzyme composed of 407 amino acids of 45 kD in the first step in tryptophan catabolism. Autoimmune diseases have been associated with some pathophysiological conditions including fetomaternal tolerance, cancer, and infectious diseases. By consuming tryptophan, an essential amino acid, it inhibits proliferation of both T lymphocytes and pathogens. By proinflammatory cytokine release such as interferon-γ, it is expressed from antigen-presenting cells, and the main role is the immunosuppressive effect. Endocan is a structurally cysteine-rich proteoglycan composed of 165 amino acids at 20 kDa. It is excreted in the microvascular endothelial cells of the lung, skin and fat tissue as well as coronary and pulmonary arteries. Endocan plays a role in the pathogenesis of various malignancies and inflammatory diseases. It plays a role in the regulation of biological processes such as adhesion, migration and proliferation of the cell. Especially its expression is elevated by vascular endothelial growth factor.

In this study, we investigated the relationship between IDO and AR, which is implicated in changes in the immune system for the etiopathogenesis. We also investigated the relationship between AR disease, in which dilated vascular structures were seen on the skin, and endocan as an endothelial marker. 81 volunteers participated in the study. The AR group consisted of 52 subjects (36 females, 16 males) while the control group consisted of 29 healthy subjects (21 males, 8 females) without any disease. Serum IDO and endocan levels were determined by ELISA.

Serum IDO levels were significantly higher in patients with AR compared to healthy group (p <0.001). Patients were also grouped according to the period of the AR (exacerbation / remission) and type (erythematotelangiectatic / papulopustular). Serum IDO levels of patients in remission period of AR and papulopustular type of AR were significantly higher than the control (p = 0.002, p = 0.001, respectively). When serum IDO levels were compared according to sex, serum IDO levels of female AR patients were higher than healthy ones (p <0.001). There was no difference between patient and control groups regarding serum endocan levels. Serum endocan levels of AR patients in the remission period were significantly higher than those in the AR patients in the exacerbation period (p = 0.014). It was seen that the type of AR had no effect on the serum endocan levels. There was no difference between groups when serum endocan levels were examined according to sex. There was also no correlation between serum IDO and endocan levels. In conclusion, serum IDO, a parameter related to immune tolerance, was found to increase in AR patients in this study. However, serum IDO levels were found to be important in gender when assessed. Contrary to expectations, there was no correlation between serum endocan levels and AR with increased local vascularity.