Takotsubo syndrome (TTS) is a stress-induced cardiomyopathy, characterized by an increased concentration of catecholamines, free radicals, and inflammatory cytokines, endothelial dysfunction, and increased apoptotic activity. High doses of isoprenaline are used in animal models to induce Takotsubo (TT)-like myocardial injury. The aim of the study was to investigate the antiapoptotic effects of liraglutide in experimental TTS and its role in the NF-κB pathway. Wistar rats were pretreated with liraglutide for 10 days, and on days 9 and 10, TT-like myocardial injury was induced with isoprenaline. After the sacrifice on day 11, hearts were isolated for histopathological and immunohistochemical analysis. Liraglutide reduced isoprenaline-induced cardiomyocyte apoptosis by decreasing cleaved caspase-3 (CC3), BCL-2-associated X protein (BAX), and NF-κB and increasing B-cell lymphoma/leukemia-2 (BCL-2). An increase in NF-κB in isoprenaline-treated rats was in positive correlation with proapoptotic markers (BAX and CC3) and in negative correlation with antiapoptotic marker BCL-2. Liraglutide increased BCL-2 and decreased NF-κB, BAX, and CC3, preserving the same correlations of NF-κB to apoptotic markers. It is concluded that liraglutide protects cardiomyocytes against isoprenaline-induced apoptosis in experimental TT-like myocardial injury through downregulation of the NF-κB pathway.
Background: Approximately 40% of patients with diffuse large B-cell lymphoma (DLBCL) experience treatment resistance to the first-line R-CHOP regimen. ATP binding cassette (ABC) transporters and survivin might play a role in multidrug resistance (MDR) in various tumors. The aim was to investigate if the coexpression of ABC transporters and survivin was associated with R-CHOP treatment response. Methods: The expression of Bcl-2, survivin, P-glycoprotein/ABCB1, MRP1/ABCC1, and BCRP/ABCC2 was analyzed using immunohistochemistry in tumor specimens obtained from patients with DLBCL, and classified according to the treatment response as Remission, Relapsed, and (primary) Refractory groups. All patients received R-CHOP or equivalent treatment. Results: Bcl-2 was in strong positive correlation with clinical parameters and all biomarkers except P-gp/ABCB1. The overexpression of MRP1/ABCC1, survivin, and BCRP/ABCC2 presented as high immunoreactive scores (IRSs) was detected in the Refractory and Relapsed groups (p < 0.05 vs. Remission), respectively, whereas the IRS of P-gp/ABCB1 was low. Significant correlations were found among either MRP1/ABCC1 and survivin or BCRP/ABCC2 in the Refractory and Relapsed groups, respectively. In multiple linear regression analysis, ECOG status along with MRP1/ABCC1 or survivin and BRCP/ABCG2 was significantly associated with the prediction of the R-CHOP treatment response. Conclusions: DLBCL might harbor certain molecular signatures such as MRP1/ABCC1, survivin, and BCRP/ABCC2 overexpression that can predict resistance to R-CHOP.
Oxidative stress is a critical pathophysiological factor in sepsis. Ursodeoxycholic acid (UDCA), a bile acid with anti-inflammatory, antioxidant, and anti-apoptotic properties, may protect against lipopolysaccharide (LPS)-induced myocardial injury. In an experimental study, 32 male Wistar rats were randomly assigned to four groups: control, LPS, UDCA, and UDCA + LPS. UDCA was administered orally for 10 days prior to LPS-induced endotoxemia. Serum levels of high-sensitive troponin I (hsTnI), homocysteine, and oxidative stress markers were measured, and immunohistochemistry and immunofluorescence were used to assess inflammation (nuclear factor kappa B, NF-κB), apoptosis (caspase 3), and signaling pathways related to protein kinase B (Akt)/NF-κB and silent information regulator 1 (SIRT1)/nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1). UDCA pretreatment significantly reduced myocardial pathological changes, serum hsTnI, homocysteine, and total oxidative stress compared with LPS alone. It enhanced catalase (CAT) activity and glutathione (GSH) levels while lowering thiobarbituric acid reactive substances (TBARS) and nitrite concentrations in cardiac tissue. UDCA modulated cellular signaling by decreasing Akt phosphorylation and activating the SIRT1/Nrf2/HO-1 pathway. These results indicate that UDCA protects the heart from LPS-induced damage by reducing oxidative stress, inflammation, and apoptosis. UDCA modulates cellular signaling by decreasing pro-inflammatory pathways and activating anti-inflammatory pathways associated with SIRT1/Nrf2/HO-1 signaling, emphasizing its key role in myocardial protection during sepsis.