Product Citations: 9

Powered by

Peripheral neurodegenerative diseases induced by irreversible peripheral nerve degeneration (PND), such as diabetic peripheral neuropathy, have a high prevalence worldwide and reduce the quality of life. However, there is no agent effective against the irreversible PND. After peripheral nerve injury, Schwann cells play an important role in regulating PND. However, because PND involves multiple biochemical events in Schwann cells, a one-drug-single-target therapeutic strategy is not feasible for PND. Here, we suggested that fascaplysin (Fas), a compound with multiple targets (CDK4/6), could overcome these problems. Fas exerted a significant inhibitory effect on axonal degradation, demyelination, and Schwann cell proliferation and dedifferentiation during in vitro and ex vivo PND. To discover the most likely novel target for PND, a chemo-bioinformatics analysis predicted the other on-targets of Fas and identified androgen receptor (AR) which were involved in Schwann cell differentiation and proliferation. AR interacted with Fas, and nuclear import of the AR/Fas complex was inhibited in Schwann cells, altering the expression patterns of transcription factors during PND. Therefore, Fas may have therapeutic potential for irreversible peripheral neurodegenerative diseases.

Challenges to docetaxel use in prostate cancer treatment include several resistance mechanisms as well as toxicity. To overcome these challenges and to improve the therapeutic efficacy in heterogeneous prostate cancer, the use of multiple agents that can destroy different subpopulations of the tumor is required. Brusatol, a multitarget inhibitor, has been shown to exhibit potent anticancer activity and play an important role in drug response and chemoresistance. Thus, the combination of brusatol and docetaxel in a nanoparticle platform for the treatment of prostate cancer is expected to produce synergistic effects. In this study, we reported the development of polymeric nanoparticles for the delivery of brusatol and docetaxel in the treatment of prostate cancer. The one-factor-at-a-time method was used to screen for formulation and process variables that impacted particle size. Subsequently, factors that had modifiable effects on particle size were evaluated using a 24 full factorial statistical experimental design followed by the optimization of drug loading. The optimization of blank nanoparticles gave a formulation with a mean size of 169.1 nm ± 4.8 nm, in agreement with the predicted size of 168.333 nm. Transmission electron microscopy showed smooth spherical nanoparticles. The drug release profile showed that the encapsulated drugs were released over 24 h. Combination index data showed a synergistic interaction between the drugs. Cell cycle analysis and the evaluation of caspase activity showed differences in PC-3 and LNCaP prostate cancer cell responses to the agents. Additionally, immunoblots showed differences in survivin expression in LNCaP cells after treatment with the different agents and formulations for 24 h and 72 h. Therefore, the nanoparticles are potentially suitable for the treatment of advanced prostate cancer.

AGE-Rich Bread Crust Extract Boosts Oxidative Stress Interception via Stimulation of the NRF2 Pathway.

In Nutrients on 29 October 2021 by Wächter, K., Navarrete Santos, A., et al.

Advanced glycation end products (AGEs) result from a non-enzymatic reaction of proteins with reactive carbohydrates. Heat-processed food, such as bread, contains high amounts of AGEs. The activation of the NF-κB signaling pathway by bread crust extract (BCE) is well understood. However, it is largely unknown whether NRF2, the master regulator of oxidative stress resistance in mammalian cells, is affected by BCE. We have investigated the molecular mechanisms by which BCE induces antioxidant gene expression in cellular models. Our data showed that soluble extracts from bread crust are capable of stimulating the NRF2 signaling pathway. Furthermore, NRF2 pathway activation was confirmed by microarray and reporter-cell analyses. QRT-PCR measurements and Western blot analyses indicated an induction of antioxidative genes such as HMOX1, GCLM and NQO1 upon BCE treatment. Moreover, BCE pretreated cells had a survival advantage compared to control cells when exposed to oxidative stress. BCE induces phosphorylation of AKT and ERK kinase in EA.hy926 cells. By mass spectrometry, several new, potentially active modifications in BCE were identified. Our findings indicate that BCE activates NRF2-dependent antioxidant gene expression, thus provoking a protection mechanism against oxidative stress-mediated tissue injury. Hence, BCE can be considered as functional food with antioxidative and cardioprotective potential.

Nrf2 regulates cell motility through RhoA-ROCK1 signalling in non-small-cell lung cancer cells.

In Scientific Reports on 13 January 2021 by Ko, E., Kim, D., et al.

Nuclear factor-erythroid 2-related factor 2 (Nrf2) is a key transcriptional regulator of several antioxidant and anti-inflammatory enzymes. It binds to its endogenous inhibitor Kelch-like ECH-associated protein 1 (Keap1) in the cytoplasm under normal conditions. Various endogenous or environmental oxidative stresses can disrupt the Nrf2/Keap1 complex, allowing Nrf2 to translocate into the nucleus, where it induces the transcription of various cytoprotective enzymes by binding to antioxidant responsive elements. These enzymes have been reported to play a role in regulating tumour growth, angiogenesis, and chemoprevention. Invasion and migration are the most harmful aspects of cancer; they directly impacts the patients' survival. Although the roles of Keap1/Nrf2 and their downstream genes in various cancers have been widely documented, their role in regulating cell motility still remains unclear, particularly in cancer cells. We observed that Nrf2 suppression following treatment with brusatol in non-small-cell lung cancer (NSCLC) cells with either exogenously introduced Keap1 or siNrf2 resulted in the inhibition of cell migration and invasion, with shrinking cell morphology due to decreased focal adhesions via inhibition of the RhoA-ROCK1 pathway. Nrf2 overexpression showed opposite results. Thus, the Nrf2/Keap1 pathway may affect cell motility by dysregulating the RhoA-ROCK1 signalling pathway in NSCLC.

Free heme regulates placenta growth factor through NRF2-antioxidant response signaling.

In Free Radical Biology and Medicine on 1 November 2019 by Kapetanaki, M. G., Gbotosho, O. T., et al.

Free heme activates erythroblasts to express and secrete Placenta Growth Factor (PlGF), an angiogenic peptide of the VEGF family. High circulating levels of PlGF have been associated in experimental animals and in patients with sickle cell disease with echocardiographic markers of pulmonary hypertension, a life-limiting complication associated with more intense hemolysis. We now show that the mechanism of heme regulation of PlGF requires the contribution of the key antioxidant response regulator NRF2. Mimicking the effect of heme, the NRF2 agonist sulforaphane stimulates the PlGF transcript level nearly 30-fold in cultured human erythroblastoid cells. Heme and sulforaphane also induce transcripts for NRF2 itself, its partners MAFF and MAFG, and its competitor BACH1. Furthermore, heme induction of the PlGF transcript is significantly diminished by the NRF2 inhibitor brusatol and by siRNA knockdown of the NRF2 and/or MAFG transcription factors. Chromatin immunoprecipitation experiments show that heme induces NRF2 to bind directly to the PlGF promoter region. In complementary in vivo experiments, mice injected with heme show a significant increase in their plasma PlGF protein as early as 3 h after treatment. Our results reveal an important mechanism of PlGF regulation, adding to the growing literature that supports the pivotal importance of the NRF2 axis in the pathobiology of sickle cell disease.Copyright © 2019 Elsevier Inc. All rights reserved.

View this product on CiteAb