👤 Błażej Stankiewicz

Exercise-induced inflammation has been shown to influence iron metabolism. Conversely, ischemic preconditioning (IPC) has been proposed as a strategy to modulate post-exercise response, especially inflammation and neurotrophic factor secretion. In this study we analyzed the effects of a 14-days IPC intervention on the post-exercises changes of the selected Iron metabolism, inflammation and neurotrophic markers in the population of non-training healthy young man. Forty healthy, untrained young men voluntarily participated in this study and were randomly assigned to two groups: an IPC group (n = 20), which underwent a 14-day IPC intervention, and a placebo (SHAM) group (n = 20). Five participants from the IPC group and seven from the SHAM group did not complete the protocol and were excluded from the analyzes. Venous blood samples were collected at rest, immediately after and 2 h after the Wingate test. Selected inflammatory and neurotrophic markers were analyzed, including IL-6, IL-10, IL-15, LIF, BDNF, IGF-1, NGF, sAPPα, FSTL-1, and GDF-15. Additionally, serum levels of iron (Fe), hepcidin (Hpc), ferritin (Fer), erythroferrone (ERFE), and erythropoietin (EPO) were assessed. IPC increased resting ferritin (~ + 9%, p < 0.05), hepcidin (~ + 12%, p < 0.05), and erythroferrone (~ + 10%, p < 0.05) concentrations. The intervention also enhanced post-exercise IGF-1 (+ 8%, p = 0.03) and sAPPα (+ 10%, p = 0.04) release and reshaped cytokine profiles, with greater early elevations of GDF-15 and IL-15 (p < 0.05) and faster normalization of FSTL-1 within 2 h (p < 0.05). IPC further affected neurotrophic signaling, showing lower 2-h post-exercise BDNF levels (p < 0.05) and distinct IGF-1 kinetics (p < 0.01). Anaerobic performance remained unchanged (p > 0.05). Ischemic preconditioning induces coordinated alterations in iron metabolism and modulates inflammatory and neurotrophic responses to anaerobic exercise, without affecting physical performance in untrained individuals. Show less

Docetaxel improves overall survival (OS) in castration-resistant prostate cancer (PCa) (CRPC) and metastatic hormone-sensitive PCa (mHSPC). However, not all patients respond due to inherent and/or acquired resistance. There remains an unmet clinical need for a robust predictive test to stratify patients for treatment. Liquid biopsy of circulating tumour cell (CTCs) is minimally invasive, can provide real-time information of the heterogeneous tumour and therefore may be a potentially ideal docetaxel response prediction biomarker. In this study we investigate the potential of using CTCs and their gene expression to predict post-docetaxel tumour response, OS and progression free survival (PFS). Peripheral blood was sampled from 18 mCRPC and 43 mHSPC patients, pre-docetaxel treatment, for CTC investigation. CTCs were isolated using the epitope independent Parsortix Detection of CTCs pre-docetaxel was associated with poor patient outcome post-docetaxel treatment. Combining total-CTC number with PSA and ALP predicted lack of partial response (PR) with an AUC of 0.90, p= 0.037 in mCRPC. A significantly shorter median OS was seen in mCRPC patients with positive CTC-score (12.80 vs. 37.33 months, HR= 5.08, p= 0.0005), ≥3 total-CTCs/7.5mL (12.80 vs. 37.33 months, HR= 3.84, p= 0.0053), ≥1 epithelial-CTCs/7.5mL (14.30 vs. 37.33 months, HR= 3.89, p= 0.0041) or epithelial to mesenchymal transitioning (EMTing)-CTCs/7.5mL (11.32 vs. 32.37 months, HR= 6.73, p= 0.0001). Significantly shorter PFS was observed in patients with ≥2 epithelial-CTCs/7.5mL (7.52 vs. 18.83 months, HR= 3.93, p= 0.0058). mHSPC patients with ≥5 CTCs/7.5mL had significantly shorter median OS (24.57 vs undefined months, HR= 4.14, p= 0.0097). In mHSPC patients, expression of While it is clear that CTC numbers and gene expression were prognostic for PCa post-docetaxel treatment, and CTC subtype analysis may have additional value, their potential predictive value for docetaxel chemotherapy response needs to be further investigated in large patient cohorts. Show less

Rho family GTPases play integral roles in neuronal differentiation and survival. We have shown previously that Clostridium difficile toxin B (ToxB), an inhibitor of RhoA, Rac1, and Cdc42, induces apoptosis of cerebellar granule neurons (CGNs). In this study, we compared the effects of ToxB to a selective inhibitor of the Rac-specific guanine nucleotide exchange factors Tiam1 and Trio (NSC23766). In a manner similar to ToxB, selective inhibition of Rac induces CGN apoptosis associated with enhanced caspase-3 activation and reduced phosphorylation of the Rac effector p21-activated kinase. In contrast to ToxB, caspase inhibitors do not protect CGNs from targeted inhibition of Rac. Also dissimilar to ToxB, selective inhibition of Rac does not inhibit MEK1/2/ERK1/2 or activate JNK/c-Jun. Instead, targeted inhibition of Rac suppresses distinct MEK5/ERK5, p90Rsk, and Akt-dependent signaling cascades known to regulate the localization and expression of the Bcl-2 homology 3 domain-only protein Bad. Adenoviral expression of a constitutively active mutant of MEK5 is sufficient to attenuate neuronal cell death induced by selective inhibition of Rac with NSC23766 but not apoptosis induced by global inhibition of Rho GTPases with ToxB. Collectively, these data demonstrate that global suppression of Rho family GTPases with ToxB causes a loss of MEK1/2/ERK1/2 signaling and activation of JNK/c-Jun, resulting in diminished degradation and enhanced transcription of the Bcl-2 homology 3 domain-only protein Bim. In contrast, selective inhibition of Rac induces CGN apoptosis by repressing unique MEK5/ERK5, p90Rsk, and Akt-dependent prosurvival pathways, ultimately leading to enhanced expression, dephosphorylation, and mitochondrial localization of proapoptotic Bad. Show less