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Background: Endothelial dysfunction, vascular inflammation and accelerated atherosclerosis have been investigated extensively in patients with chronic kidney disease (CKD). These conditions, as well as protein–energy malnutrition and oxidative stress, impair kidney function and contribute to increased morbidity and mortality among patients with end-stage kidney disease undergoing hemodialysis (HD). TXNIP, a key regulator of oxidative stress, has been linked to inflammation and suppresses eNOS activity. STAT3 activation adds to endothelial cell dysfunction, macrophage polarization, immunity and inflammation. Therefore, it is critically involved in atherosclerosis. This study evaluated the effect of sera from HD patients on the TXNIP-eNOS-STAT3 pathway using an in vitro model of human umbilical vein endothelial cells (HUVECs). Methods: Thirty HD patients with end-stage kidney disease and ten healthy volunteers were recruited. Serum samples were taken at dialysis initiation. HUVECs were treated with HD or healthy serum (10% v/v) for 24 h. Then, cells were collected for mRNA and protein analysis. Results: TXNIP mRNA and protein expression were significantly increased in HUVECs treated with HD serum compared to healthy controls (fold changes: 2.41 ± 1.84 vs. 1.41 ± 0.5 and 2.04 ± 1.16 vs. 0.92 ± 0.29, respectively), as were IL-8 mRNA (fold changes: 2.22 ± 1.09 vs. 0.98 ± 0.64) and STAT3 protein expression (fold changes: 1.31 ± 0.75 vs. 0.57 ± 0.43). The expression of eNOS mRNA and protein (fold changes: 0.64 ± 0.11 vs. 0.95 ± 0.24; 0.56 ± 0.28 vs. 4.35 ± 1.77, respectively) and that of SOCS3 and SIRT1 proteins were decreased. Patients’ nutritional status, reflected by their malnutrition–inflammation scores, did not affect these inflammatory markers. Conclusions: This study showed that sera from HD patients stimulated a novel inflammatory pathway, regardless of their nutritional status.

Background: Endothelial dysfunction, vascular inflammation and accelerated atherosclerosis have been investigated extensively in patients with chronic kidney disease (CKD). These conditions, as well as protein–energy malnutrition and oxidative stress, impair kidney function and contribute to increased morbidity and mortality among patients with end-stage kidney disease undergoing hemodialysis (HD). TXNIP, a key regulator of oxidative stress, has been linked to inflammation and suppresses eNOS activity. STAT3 activation adds to endothelial cell dysfunction, macrophage polarization, immunity and inflammation. Therefore, it is critically involved in atherosclerosis. This study evaluated the effect of sera from HD patients on the TXNIP-eNOS-STAT3 pathway using an in vitro model of human umbilical vein endothelial cells (HUVECs). Methods: Thirty HD patients with end-stage kidney disease and ten healthy volunteers were recruited. Serum samples were taken at dialysis initiation. HUVECs were treated with HD or healthy serum (10% v/v) for 24 h. Then, cells were collected for mRNA and protein analysis. Results: TXNIP mRNA and protein expression were significantly increased in HUVECs treated with HD serum compared to healthy controls (fold changes: 2.41 ± 1.84 vs. 1.41 ± 0.5 and 2.04 ± 1.16 vs. 0.92 ± 0.29, respectively), as were IL-8 mRNA (fold changes: 2.22 ± 1.09 vs. 0.98 ± 0.64) and STAT3 protein expression (fold changes: 1.31 ± 0.75 vs. 0.57 ± 0.43). The expression of eNOS mRNA and protein (fold changes: 0.64 ± 0.11 vs. 0.95 ± 0.24; 0.56 ± 0.28 vs. 4.35 ± 1.77, respectively) and that of SOCS3 and SIRT1 proteins were decreased. Patients' nutritional status, reflected by their malnutrition–inflammation scores, did not affect these inflammatory markers. Conclusions: This study showed that sera from HD patients stimulated a novel inflammatory pathway, regardless of their nutritional status. [ABSTRACT FROM AUTHOR]

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic and ultimately fatal disease characterized by a progressive decline in lung function. Fibrotic diseases, such as IPF, are characterized by uncontrolled activation of fibroblasts. Since the microenvironment is known to affect cell behavior, activated fibroblasts can in turn activate healthy neighboring cells. Thus, we investigated IPF paracrine signaling in human lung fibroblasts (HLFs) derived from patients with IPF.Methods: Primary human fibroblast cultures from IPF (IPF-HLF) and control donor (N-HLF) lung tissues were established and their supernatants were collected. These supernatants were then added to N-HLFs for further culture. Protein and RNA were extracted from IPF/ N-HLFs at baseline. Interleukin-6 (IL-6) and TGF-β-related signaling factors (e.g. STAT3, Smad3) were evaluated by western blot and qPCR. IL-6 levels were measured by ELISA. IL-6 signaling was blocked by Tocilizumab (TCZ) (10 ng/ml).Results: IPF-HLFs were found to significantly overexpress IL-6 receptor (IL-6R), suppressor of cytokine signaling 3 (SOCS3), phospho-STAT3-Y705 and phospho-Smad3 in comparison to N-HLFs (p < 0.05). In addition, they were found to proliferate faster, secrete more IL-6 and express higher levels of the soluble IL-6R. IPF-HLF increased proliferation was inhibited by TCZ. Moreover, IPF-HLF derived supernatants induced both direct and indirect STAT3 activation that resulted in Smad3 phosphorylation and elevated Gremlin levels in N-HLFs. These effects were also successfully blocked by TCZ.Conclusions: IPF-HLF paracrine signaling leads to IL-6R overexpression, which in turn, affects N-HLF survival. The IL-6/STAT3/Smad3 axis facilitates cellular responses that could potentially promote fibrotic disease. This interplay was successfully blocked by TCZ. [ABSTRACT FROM AUTHOR]

To evaluate changes in the inflammatory response of thioredoxin (TXN), thioredoxin interacting protein (TXNIP), transducer and activator of transcription 3, NFƙB-p50 and STAT3 at the level of maternal serum, placenta, and umbilical cord blood of women with gestational diabetes mellitus type 2 (GDMA2) compared to normal pregnancies (NP). Thirty pregnant women (20 with GDMA2 and 10 NP) were recruited during admission for delivery. Blood samples were obtained from the parturients and umbilical cords, as well as placental tissue for mRNA and protein extraction. TXNIP mRNA expression was significantly increased in maternal serum of women with GDMA2 compared to NP women. TXNIP mRNA was significantly decreased in GDMA2 placentas and cord blood compared to NP. TXN/TXNIP mRNA ratio showed significantly high absolute values in placental and cord blood (2.39 and 1.66) respectively, compared to maternal ratio (1.084) (P < 0.001). TXN/TXNIP placenta protein ratio showed similar values between GDMA2 and NP (0.98 and 0.86; P = 0.7). STAT3 and its target protein SOCS3, as well as NFƙB-p50 mRNA expression were significantly increased in placentas of GDMA2. NFƙB-p50 mRNA expression was significantly decreased in cord blood compared to both maternal and placental mRNA expression. Pro-inflammatory changes are expressed by low mRNA TXN/TXNIP ratio in maternal blood of GDMA2 patients, but not in placental and umbilical cord blood samples. This, as well as the feedback role of SOCS3 in STAT3 pathway and NFƙB-p50 expression, may indicate that the placenta has a role in protecting the fetus from damage due to inflammatory response, which is common in diabetes. [ABSTRACT FROM AUTHOR]

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