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Objectives: Transglutaminase 2 (TG2) is a unique protein having enzymatic and nonenzymatic functions that have been implicated in various biological and pathological processes such as cell survival and apoptosis, cell signaling, differentiation, adhesion and migration, wound healing and inflammation. As reported in previous studies, TG2 expression and activity increase by age suggesting that TG2 possibly has roles in cellular aging process. In this study, we aimed to explore the role of TG2 in chronological skin aging through its impact on the expression of some important extracellular matrix (ECM) proteins including TGF-β, TIMP-1 and TIMP-2. Methods: We have compared TG2 expression and activity in young and in vitro chronologically aged human dermal fibroblasts via Western blot and in situ TG2 activity assays. Afterwards, we inhibited TG2 expression via siRNA transfection and activity via active site inhibitor of TG2 separately in aged dermal fibroblasts and monitored the expression levels of TGF-β, TIMP-1 and TIMP-2 in these cells by Western blot and compared to that of untreated control cells. Results: We obtained evidence that both TG2 expression and activity increase in aged cells. However, protein levels of TGF-β, TIMP-1 and TIMP-2 do not exhibit any significant difference in TG2 downregulated or TG2 activity inhibited aged cells compared to control cells. Conclusions: Our results indicate that changes in the expression and activity of TG2 in ( in vitro ) chronologically aged human dermal fibroblasts do not impact the expression patterns of TGF-β, TIMP-1 and TIMP-2 proteins.

Article Poster Full Texts was published on February 1, 2023 in the journal Turkish Journal of Biochemistry (volume 48, issue s1).

Article From 2008 to 2018: FEBS education activities bringing us to FEBS Izmir workshop 2018 “Molecular life sciences education- training tomorrow’s scientists” (Sept 6-8th, 2018) was published on June 6, 2022 in the journal Turkish Journal of Biochemistry (volume 0, issue 0).

Amaç: Bu çalışmada, 2019-20 eğitim yılı bahar yarıyılında İEÜTF tıp eğitiminde, COVID-19 pandemisinde uyarlanan yöntemleri/uygulamaları tanımlamak ve sonuçlarını tartışmak amaçlanmaktadır. Gereç ve Yöntem: Makalede İEÜTF tıp eğitimi tanıtılmış, pandemi nedeniyle eğitim programında yapılan değişiklikler, eğitimin nasıl yürütüldüğü ve değerlendirmesi konusundaki bilgiler paylaşılmıştır. Bulgular: İEÜTF pandemi öncesinde de eğitimde teknolojiyi yaygın kullanmakta olup, uzaktan eğitime neredeyse hiç ara vermeden başlayabilmiş, planlanan eğitsel etkinlikler gerçekleştirilmiştir. Bunda İEÜTF’de yalnızca ilk üç sınıfın eğitim görmesinin payı da büyüktür. Yüz yüze eğitimin zorunlu olduğu teknik ve klinik beceri uygulamaları ertelenmiştir. Sonuç: Halen yaşanan COVID-19 pandemi sürecinde tıp eğitiminde klinik eğitimlerin nasıl yürütüleceği konusunda stratejiler geliştirilmelidir. Yaşanan tüm bu sürecin, uzun vadede tıp eğitiminde değişikliğe neden olacağı düşünülmektedir.

Objectives: This study aims to evaluate the antioxidant effects of epigallocatechin-3-gallate (EGCG) in a bleomycin (BLM)-induced scleroderma model. Materials and methods: Thirty-two healthy female Balb-c mice (6-8-week-old; weighing 22±5 g) were used in this study. The mice were randomly divided into four groups: control (n=8), BLM (n=8), BLM+EGCG (n=8), and EGCG (n=8). Skin tissue specimens were collected at the end of the experiments. Histopathological examinations of skin tissues were performed. Skin samples were assessed for total superoxide dismutase activity and malondialdehyde content. The phosphorylation of p-38 mitogen-activated protein kinase and Akt protein (the serine-threonine protein kinase encoded by the AKT), as well as the nuclear factor-kappa B levels, were analyzed by western blotting. Results: Epigallocatechin-3-gallate-treated groups were observed to have reduced connective tissue fibrosis in the dermis area using Masson’s trichrome staining method. Pp-38 and nuclear factor-kappa B were found to decrease significantly in the BLM + EGCG group compared with the BLM group. Parallel to these findings, phosphorylated Akt protein was found to increase in the BLM + EGCG group compared with the BLM group. Superoxide dismutase activity was increased in the EGCG group and content of malondialdehyde level was decreased in EGCG groups. Conclusion: The results of the present study demonstrated that EGCG represses pp-38 and nuclear factor-kappa B signaling pathways, exerting a protective effect for scleroderma through its anti-oxidative role.

Article IS-05 PhD TRAINING: NEW PROSPECTS was published on September 1, 2018 in the journal Turkish Journal of Biochemistry (volume 43, issue s4).

Glioblastoma multiforme (GBM) is caused by the central nervous system-derived glial cells, and represents the most common (50%-60%) form of primary brain tumors. The aim of this study was to investigate the in vitro effects of selenium...

Matrix metalloproteinases (MMPs) are enzymes that are responsible for degradation of extracellular matrix (ECM); they are involved in the pathogenesis of ischemia-re-perfusion (I-R) injury. We investigated the possible preventive effect of alpha-lipoic acid (LA) in a renal I-R injury model in rats by assessing its reducing effect on the expression and activation of MMP-2 and MMP-9 induced by I-R. Rats were assigned to four groups: control, sham-operated, I-R (saline, i.p.) and I-R+ LA (100 mg/kg, i.p.). After a right nephrectomy, I-R was induced by clamping the left renal pedicle for 1 h, followed by 6 h re-perfusion. In the sham group, a right nephrectomy was performed and left renal pedicles were dissected without clamping and the entire left kidney was excised after 6 h. LA pretreatment was started 30 min prior to induction of ischemia. Injury to tubules was evaluated using light and electron microscopy. The expressions of MMP-2 and MMP-9 were determined by immunohistochemistry and their activities were analyzed by gelatin zymography. Serum creatinine was measured using a quantitative kit based on the Jaffe colorimetric technique. Malondialdehyde (MDA) and glutathione (GSH) were analyzed using high performance liquid chromatography. Tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-1 were assessed using enzyme-linked immunosorbent assay (ELISA). I-R caused tubular dilatation and brush border loss. LA decreased both renal dysfunction and abnormal levels of MDA and GSH during I-R. Moreover, LA decreased significantly both MMP-2 and MMP-9 expressions and activations during I-R. TIMP-1 and TIMP-2 levels were increased significantly by LA administration. LA modulated increased MMP-2 and MMP-9 activities and decreased TIMP-1 and TIMP-2 levels during renal I-R.

Aim: Nonalcoholic fatty liver disease (NAFLD) is associated with inflammation and increased risk of atherosclerosis. Neopterin is regarded as a biochemical marker of cell-mediated immunity, which is secreted by monocytes and macrophages, mainly in response to interferon-gamma. The aim of the present study was to investigate the serum neopterin levels in obese adolescents and compare the neopterin levels in patients with and without NAFLD and also with healthy controls. The second aim of the study was to research the possible relationship between neopterin levels and adipokines (leptin, adiponectin, resistin, and ghrelin). Methods: Ninety-three obese adolescents (39 with NAFLD, 54 without NAFLD) and 55 healthy controls were enrolled in the study. Serum levels of neopterin and adipokines were measured with high-performance liquid chromatography and sandwich enzyme-linked immunosorbent assay, respectively. Results: Serum neopterin levels were significantly higher in patients with NAFLD (3.20 +/- 0.09 nmol/L) than in their healthy peers (2.91 +/- 0.08 nmol/L) (p=0.020). Neopterin levels were positively correlated with leptin levels in obese patients (r=0.380, p<0.001) and in the group comprising all individuals (r=0.206, p<0.05). There was no correlation between neopterin concentrations and relative weight, alanin aminotransferase, adiponectin, resistin, and ghrelin levels. Conclusion: The serum neopterin levels were significantly higher in obese adolescents with fatty liver disease compared to controls, and this may be related to increased cell-mediated immunity in fatty liver disease.