TRP14 is the rate-limiting enzyme for intracellular cystine reduction and regulates proteome cysteinylation.

It has remained unknown how cells reduce cystine taken up from the extracellular space, which is a required step for further utilization of cysteine in key processes such as protein or glutathione synthesis. Here, we show that the thioredoxin-related protein of 14 kDa (TRP14, encoded by TXNDC17) is the rate-limiting enzyme for intracellular cystine reduction. When TRP14 is genetically knocked out, cysteine synthesis through the transsulfuration pathway becomes the major source of cysteine in human cells, and knockout of both pathways becomes lethal in C. elegans subjected to proteotoxic stress. TRP14 can also reduce cysteinyl moieties on proteins, rescuing their activities as here shown with cysteinylated peroxiredoxin 2. Txndc17 knockout mice were, surprisingly, protected in an acute pancreatitis model, concomitant with activation of Nrf2-driven antioxidant pathways and upregulation of transsulfuration. We conclude that TRP14 is the evolutionarily conserved enzyme principally responsible for intracellular cystine reduction in C. elegans, mice, and humans.

The Melatonin Derivative ITH13001 Prevents Hypertension and Cardiovascular Alterations in Angiotensin II-Infused Mice.

Inflammatory mechanisms and oxidative stress seem to contribute to the pathogenesis of hypertension. ITH13001 is a melatonin-phenyl-acrylate hybrid that moderately induces the antioxidant transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) and has a potent oxidant scavenging effect compared with other derivatives of its family. Here we investigated the effect of ITH13001 on hypertension and the associated cardiovascular alterations. Angiotensin II (AngII)-infused mice were treated with ITH13001 (1 mg/kg per day, i.p.) for 2 weeks. The ITH13001 treatment prevented: 1) the development of hypertension, cardiac hypertrophy, and increased collagen and B-type natriuretic peptide (Bnp) expression in the heart; 2) the reduction of elasticity, incremental distensibility, fenestrae area, intraluminal diameter, and endothelial cell number in mesenteric resistance arteries (MRA); 3) the endothelial dysfunction in aorta and MRA; 4) the plasma and cardiovascular oxidative stress and the reduced aortic nitric oxide (NO) bioavailability; 5) the increased cardiac levels of the cytokines interleukin (IL)-1ß, IL-6, and C-C motif chemokine ligand 2 (Ccl2), the T cell marker cluster of differentiation 3 (Cd3), the inflammasome NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3), the proinflammatory enzymes inducible nitric oxide synthase (iNOS) and COX-2, the toll-like receptor 4 (TLR4) adapter protein myeloid differentiation primary response 88 (MyD88), and the nuclear factor kappa B (NF-κB) subunit p65; 6) the greater aortic expression of the cytokines tumor necrosis factor alpha (Tnf-α), Ccl2 and IL-6, Cd3, iNOS, MyD88, and NLRP3. Although ITH13001 increased nuclear Nrf2 levels and heme oxygenase 1 (HO-1) expression in vascular smooth muscle cells, both cardiac and vascular Nrf2, Ho-1, and NADPH quinone dehydrogenase 1 (Nqo1) levels remained unmodified irrespective of AngII infusion. Summarizing, ITH13001 improved hypertension-associated cardiovascular alterations independently of Nrf2 pathway activation, likely due to its direct antioxidant and anti-inflammatory properties. Therefore, ITH13001 could be a useful therapeutic strategy in patients with resistant hypertension. SIGNIFICANCE STATEMENT: Despite the existing therapeutic arsenal, only half of the patients treated for hypertension have adequately controlled blood pressure; therefore, the search for new compounds to control this pathology and the associated damage to end-target organs (cerebral, cardiac, vascular, renal) is of particular interest. The present study demonstrates that a new melatonin derivative, ITH13001, prevents hypertension development and the associated cardiovascular alterations due to its antioxidant and anti-inflammatory properties, making this compound a potential candidate for treatment of resistant hypertensive patients.

Resveratrol-Based MTDLs to Stimulate Defensive and Regenerative Pathways and Block Early Events in Neurodegenerative Cascades.

By replacing a phenolic ring of (E)-resveratrol with an 1,3,4-oxadiazol-2(3H)-one heterocycle, new resveratrol-based multitarget-directed ligands (MTDLs) were obtained. They were evaluated in several assays related to oxidative stress and inflammation (monoamine oxidases, nuclear erythroid 2-related factor, quinone reductase-2, and oxygen radical trapping) and then in experiments of increasing complexity (neurogenic properties and neuroprotection vs okadaic acid). 5-[(E)-2-(4-Methoxyphenyl)ethenyl]-3-(prop-2-yn-1-yl)-1,3,4-oxadiazol-2(3H)-one (4e) showed a well-balanced MTDL profile: cellular activation of the NRF2-ARE pathway (CD = 9.83 µM), selective inhibition of both hMAO-B and QR2 (IC50s = 8.05 and 0.57 µM), and the best ability to promote hippocampal neurogenesis. It showed a good drug-like profile (positive in vitro central nervous system permeability, good physiological solubility, no glutathione conjugation, and lack of PAINS or Lipinski alerts) and exerted neuroprotective and antioxidant actions in both acute and chronic Alzheimer models using hippocampal tissues. Thus, 4e is an interesting MTDL that could stimulate defensive and regenerative pathways and block early events in neurodegenerative cascades.

Novel Series of Dual NRF2 Inducers and Selective MAO-B Inhibitors for the Treatment of Parkinson's Disease.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease. It is characterized by a complex network of physiopathological events where oxidative stress plays a central role among other factors such as neuroinflammation and protein homeostasis. Nuclear factor-erythroid 2 p45-related factor 2 (NRF2) has a multitarget profile itself as it controls a plethora of cellular processes involved in the progression of the disease. In this line, we designed a novel family of 2-(1H-indol-3-yl)ethan-1-amine derivatives as NRF2 inducers with complementary activities. Novel compounds are based on melatonin scaffold and include, among other properties, selective monoamine oxidase B (MAO-B) inhibition activity. Novel multitarget compounds exhibited NRF2 induction activity and MAO-B selective inhibition, combined with anti-inflammatory, antioxidant, and blood-brain barrier permeation properties. Furthermore, they exert neuroprotective properties against oxidative stress toxicity in PD-related in vitro. Hit compound 14 reduced oxidative stress markers and exerted neuroprotection in rat striatal slices exposed to 6-hydroxydopamine or rotenone. In conclusion, we developed a promising family of dual NRF2 inducers and selective MAO-B inhibitors that could serve as a novel therapeutic strategy for PD treatment.

Enantioselective Synthesis and Pharmacological Evaluation of Aza-CGP37157-Lipoic Acid Hybrids for the Treatment of Alzheimer's Disease.

Hybrids based on an aza-analogue of CGP37157, a mitochondrial Na+/Ca2+ exchanger antagonist, and lipoic acid were obtained in order to combine in a single molecule the antioxidant and NRF2 induction properties of lipoic acid and the neuroprotective activity of CGP37157. The four possible enantiomers of the hybrid structure were synthesized by using as the key step a fully diastereoselective reduction induced by Ellman's chiral auxiliary. After computational druggability studies that predicted good ADME profiles and blood-brain permeation for all compounds, the DPPH assay showed moderate oxidant scavenger capacity. Following a cytotoxicity evaluation that proved the compounds to be non-neurotoxic at the concentrations tested, they were assayed for NRF2 induction capacity and for anti-inflammatory properties and measured by their ability to inhibit nitrite production in the lipopolysaccharide-stimulated BV2 microglial cell model. Moreover, the compounds were studied for their neuroprotective effect in a model of oxidative stress achieved by treatment of SH-SY5Y neuroblastoma cells with the rotenone-oligomycin combination and also in a model of hyperphosphorylation induced by treatment with okadaic acid. The stereocenter configuration showed a critical influence in NRF2 induction properties, and also in the neuroprotection against oxidative stress experiment, leading to the identification of the compound with S and R configuration as an interesting hit with a good neuroprotective profile against oxidative stress and hyperphosphorylation, together with a relevant anti-neuroinflammatory activity. This interesting multitarget profile will be further characterized in future work.

Enhanced Stability and Bioactivity of Natural Anticancer Topoisomerase I Inhibitors through Cyclodextrin Complexation.

The use of cyclodextrins as drug nano-carrier systems for drug delivery is gaining importance in the pharmaceutical industry due to the interesting pharmacokinetic properties of the resulting inclusion complexes. In the present work, complexes of the anti-cancer alkaloids camptothecin and luotonin A have been prepared with ß-cyclodextrin and hydroxypropyl-ß-cyclodextrin. These cyclodextrin complexes were characterized by nuclear magnetic resonance spectroscopy (NMR). The variations in the 1H-NMR and 13C-NMR chemical shifts allowed to establish the inclusion modes of the compounds into the cyclodextrin cavities, which were supported by docking and molecular dynamics studies. The efficiency of the complexation was quantified by UV-Vis spectrophotometry and spectrofluorimetry, which showed that the protonation equilibria of camptothecin and luotonin A were drastically hampered upon formation of the inclusion complexes. The stabilization of camptothecin towards hydrolysis inside the cyclodextrin cavity was verified by the quantitation of the active lactone form by reverse phase liquid chromatography fluorimetric detection, both in basic conditions and in the presence of serum albumin. The antitumor activity of luotonin A and camptothecin complexes were studied in several cancer cell lines (breast, lung, hepatic carcinoma, ovarian carcinoma and human neuroblastoma) and an enhanced activity was found compared to the free alkaloids, particularly in the case of hydroxypropyl-ß-cyclodextrin derivatives. This result shows that the cyclodextrin inclusion strategy has much potential towards reaching the goal of employing luotonin A or its analogues as stable analogues of camptothecin.

Bisavenathramide Analogues as Nrf2 Inductors and Neuroprotectors in In Vitro Models of Oxidative Stress and Hyperphosphorylation.

Oxidative stress is crucial to the outbreak and advancement of neurodegenerative diseases and is a common factor to many of them. We describe the synthesis of a library of derivatives of the 4-arylmethylen-2-pyrrolin-5-one framework by sequential application of a three-component reaction of primary amines, ß-dicarbonyl compounds, and α-haloketones and a Knoevenagel condensation. These compounds can be viewed as cyclic amides of caffeic and ferulic acids, and are also structurally related to the bisavenanthramide family of natural antioxidants. Most members of the library showed low cytotoxicity and good activity as inductors of Nrf2, a transcription factor that acts as the master regulator of the antioxidant response associated with activation of the antioxidant response element (ARE). Nrf2-dependent protein expression was also proved by the significant increase in the levels of the HMOX1 and NQO1 proteins. Some compounds exerted neuroprotective properties in oxidative stress situations, such as rotenone/oligomycin-induced toxicity, and also against protein hyperphosphorylation induced by the phosphatase inhibitor okadaic acid. Compound 3i, which can be considered a good candidate for further hit-to-lead development against neurodegenerative diseases due to its well-balanced multitarget profile, was further characterized by proving its ability to reduce phosphorylated Tau levels.

A chemical screen for modulators of mRNA translation identifies a distinct mechanism of toxicity for sphingosine kinase inhibitors.

We here conducted an image-based chemical screen to evaluate how medically approved drugs, as well as drugs that are currently under development, influence overall translation levels. None of the compounds up-regulated translation, which could be due to the screen being performed in cancer cells grown in full media where translation is already present at very high levels. Regarding translation down-regulators, and consistent with current knowledge, inhibitors of the mechanistic target of rapamycin (mTOR) signaling pathway were the most represented class. In addition, we identified that inhibitors of sphingosine kinases (SPHKs) also reduce mRNA translation levels independently of mTOR. Mechanistically, this is explained by an effect of the compounds on the membranes of the endoplasmic reticulum (ER), which activates the integrated stress response (ISR) and contributes to the toxicity of SPHK inhibitors. Surprisingly, the toxicity and activation of the ISR triggered by 2 independent SPHK inhibitors, SKI-II and ABC294640, the latter in clinical trials, are also observed in cells lacking SPHK1 and SPHK2. In summary, our study provides a useful resource on the effects of medically used drugs on translation, identified compounds capable of reducing translation independently of mTOR and has revealed that the cytotoxic properties of SPHK inhibitors being developed as anticancer agents are independent of SPHKs.

Fear of Cancer Progression and Health Behaviors in Patients with Colorectal Cancer.

Objectives: Preparation of patients for colon tumor resection, which involves giving up smoking, reducing alcohol intake, having a proper diet, and increasing physical activity, significantly shortens the hospitalization period. In this study, we aimed at determining the relationship between the fear of cancer progression (FoP) and health behaviors among people with colon cancer. Methods: Participants were patients a week before a colon tumor surgery and 6 months after. Measured variables included smoking, alcohol intake, anti-health products intake (anti-health behaviors), physical activity, pro-health products intake (pro-health behaviors), and fear of progression cancer. Results: Comparing the week before the surgery and 6 months after revealed a decrease in smoking (η² = .02), alcohol intake (η² = .03), anti-health products intake (η² = .06) and physical activity (η² = .06). A higher level of fear of cancer progression is related to decrease in anti-health behaviors, but does not affect the change in health-promoting behaviors among patients with colorectal cancer. Conclusions: FoP is an important factor facilitating the limitation of anti-health behaviors such as alcohol and anti-health products intake. Symptoms of colorectal cancer have negative influence on physical activity and intake of pro-health products.

Perspective of Internet Poker Players on Harm-Reduction Strategies: A Cross-Sectional Study.

Background: Internet gambling may increase rates of gambling harm. This current study aimed to assess Internet poker players' views on various harm-reduction (HR) strategies. It also examined differences in these views according to the games played (poker only vs. poker plus other gambling activities), indebtedness, and problem gambling severity. Methods: Internet poker players (n = 311; 94.2% Male) recruited online between 2012 and 2014 were included in the analyses and completed a survey on indebtedness, problem gambling severity index, and ten statements regarding HR features. Results: Among the whole sample, the most frequently endorsed HR strategy was setting money limits, specialized online help, and peer support forums. People who play poker only (70%) are less prone to endorse the utility of information on excessive gambling and specialized healthcare centers. No differences were found between those people with debt versus those without regarding HR assessment. Participants with severe problem gambling were more skeptical about HR strategies based on information on specialized healthcare centers. Conclusion: Setting money limits, online help, and peer support forums are the most commonly endorsed strategies. Future research is needed to evaluate the effectiveness of online harm reduction strategies.

When It Comes to an End: Oxidative Stress Crosstalk with Protein Aggregation and Neuroinflammation Induce Neurodegeneration.

Neurodegenerative diseases are characterized by a progressive loss of neurons in the brain or spinal cord that leads to a loss of function of the affected areas. The lack of effective treatments and the ever-increasing life expectancy is raising the number of individuals affected, having a tremendous social and economic impact. The brain is particularly vulnerable to oxidative damage given the high energy demand, low levels of antioxidant defenses, and high levels of metal ions. Driven by age-related changes, neurodegeneration is characterized by increased oxidative stress leading to irreversible neuronal damage, followed by cell death. Nevertheless, neurodegenerative diseases are known as complex pathologies where several mechanisms drive neuronal death. Herein we discuss the interplay among oxidative stress, proteinopathy, and neuroinflammation at the early stages of neurodegenerative diseases. Finally, we discuss the use of the Nrf2-ARE pathway as a potential therapeutic strategy based on these molecular mechanisms to develop transformative medicines.

Antioxidant, Anti-inflammatory and Neuroprotective Profiles of Novel 1,4-Dihydropyridine Derivatives for the Treatment of Alzheimer's Disease.

Alzheimer's disease is a chronic and irreversible pathological process that has become the most prevalent neurodegenerative disease. Currently, it is considered a multifactorial disease where oxidative stress and chronic neuroinflammation play a crucial role in its onset and development. Its characteristic neuronal loss has been related to the formation of neurofibrillary tangles mainly composed by hyperphosphorylated tau protein. Hyperphosphorylation of tau protein is related to the over-activity of GSK-3ß, a kinase that participates in several pathological mechanisms including neuroinflammation. Neuronal loss is also related to cytosolic Ca2+ homeostasis dysregulation that triggers apoptosis and free radicals production, contributing to oxidative damage and, finally, neuronal death. Under these premises, we have obtained a new family of 4,7-dihydro-2H-pyrazolo[3-b]pyridines as multitarget directed ligands showing potent antioxidant properties and able to scavenge both oxygen and nitrogen radical species, and also, with anti-inflammatory properties. Further characterization has demonstrated their capacity to inhibit GSK-3ß and to block L-type voltage dependent calcium channels. Novel derivatives have also demonstrated an interesting neuroprotective profile on in vitro models of neurodegeneration. Finally, compound 4g revokes cellular death induced by tau hyperphosphorylation in hippocampal slices by blocking reactive oxygen species (ROS) production. In conclusion, the multitarget profile exhibited by these compounds is a novel therapeutic strategy of potential interest in the search of novel treatments for Alzheimer's disease.

New Nrf2-Inducer Compound ITH12674 Slows the Progression of Retinitis Pigmentosa in the Mouse Model rd10.

BACKGROUND/AIMS: It is well established that oxidative stress and inflammation are common pathogenic features of retinal degenerative diseases. ITH12674 is a novel compound that induces the transcription factor Nrf2; in so doing, the molecule exhibits anti-inflammatory, and antioxidant properties, and affords neuroprotection in rat cortical neurons subjected to oxidative stress. We here tested the hypothesis that ITH12674 could slow the retinal degeneration that causes blindness in rd10 mice, a model of retinitis pigmentosa. METHODS: Animals were intraperitoneally treated with 1 or 10 mg/Kg ITH12674 or placebo from P16 to P30. At P30, retinal functionality and visual acuity were analyzed by electroretinography and optomotor test. By immunohistochemistry we quantified the photoreceptor rows and analyzed their morphology and connectivity. Oxidative stress and inflammatory state was studied by Western blot, and microglia reactivity was monitored by flow cytometry. The blood-brain barrier permeation of ITH12674 was evaluated using a PAMPA-BBB assay. RESULTS: In rd10 mice treated with 10 mg/Kg of the compound, the following changes were observed (with respect to placebo): (i) a decrease of vision loss with higher scotopic a- and b-waves; (ii) increased visual acuity; (iii) preservation of cone photoreceptors morphology, as well as their synaptic connectivity; (iv) reduced expression of TNF-α and NF-κB; (v) increased expression of p38 MAPK and Atg12-Atg5 complex; and (vi) decreased CD11c, MHC class II and CD169 positive cell populations. CONCLUSION: These data support the view that a Nrf2 inducer compound may arise as a new therapeutic strategy to combat retinal neurodegeneration. At present, we are chemically optimising compound ITH12674 with the focus on improving its neuroprotective potential in retinal neurodegenerative diseases.

Tuning melatonin receptor subtype selectivity in oxadiazolone-based analogues: Discovery of QR2 ligands and NRF2 activators with neurogenic properties.

New multi-target indole and naphthalene derivatives containing the oxadiazolone scaffold as a bioisostere of the melatonin acetamido group have been developed. The novel compounds were characterized at melatonin receptors MT1R and MT2R, quinone reductase 2 (QR2), lipoxygenase-5 (LOX-5), and monoamine oxidases (MAO-A and MAO-B), and also as radical scavengers. We found that selectivity within the oxadiazolone series can be modulated by modifying the side chain functionality and co-planarity with the indole or naphthalene ring. In phenotypic assays, several oxadiazolone-based derivatives induced signalling mediated by the transcription factor NRF2 and promoted the maturation of neural stem-cells into a neuronal phenotype. Activation of NRF2 could be due to the binding of indole derivatives to KEAP1, as deduced from surface plasmon resonance (SPR) experiments. Molecular modelling studies using the crystal structures of QR2 and the KEAP1 Kelch-domain, as well as the recently described X-ray free-electron laser (XFEL) structures of chimeric MT1R and MT2R, provided a rationale for the experimental data and afforded valuable insights for future drug design endeavours.

Melatonin-sulforaphane hybrid ITH12674 attenuates glial response in vivo by blocking LPS binding to MD2 and receptor oligomerization.

Neuroinflammation is increasingly associated to the onset and progression of neurodegenerative diseases. Furthermore, several lines of evidence have demonstrated the capacity of aberrant protein aggregates to activate the immune response, accelerating the advance of the disease. Compound ITH12674 is a melatonin-sulforaphane hybrid designed to exert a dual drug-prodrug mechanism of action that combines potent NRF2 induction and free radical scavenger activity. ITH12674 also showed neuroprotective properties in oxidative stress related models, that were dependant on its NRF2 inducing properties. Given the high impact of neuroinflammation in the pathogenesis of neurodegeneration, we foresaw to study the anti-inflammatory properties of ITH12674. ITH12674 reduced inflammatory markers in glial cell cultures and hippocampal tissue after LPS administration. The anti-inflammatory effect was related to inhibition of TLR4 receptors due to a direct interaction with the TLR4/MD2 complex at the hydrophobic cavity of MD2. ITH12674 is endowed with anti-inflammatory properties, that are complementary to the NRF2 inducing activity and neuroprotective properties. Thus, ITH12674 could be of potential interest for the treatment of diseases with chronic neuroinflammation.

Aza-CGP37157-lipoic hybrids designed as novel Nrf2-inducers and antioxidants exert neuroprotection against oxidative stress and show neuroinflammation inhibitory properties.

Two multitarget hybrids, derived from an aza-analogue of CGP37157, a mitochondrial Na+ /Ca2+ exchanger antagonist, and lipoic acid were designed in order to combine in a single molecule the antioxidant and Nrf2 induction properties of lipoic acid and the neuroprotective activity of CGP37157. The hybrid derivatives showed Nrf2 induction and radical scavenging properties, leading to a good neuroprotective profile against oxidative stress, together with an interesting antineuroinflammatory activity. The results obtained show differences in activity depending on the configuration of the chiral center of LA.

Nrf2 Plays a Protective Role Against Intravascular Hemolysis-Mediated Acute Kidney Injury.

Massive intravascular hemolysis is associated with acute kidney injury (AKI). Nuclear factor erythroid-2-related factor 2 (Nrf2) plays a central role in the defense against oxidative stress by activating the expression of antioxidant proteins. We investigated the role of Nrf2 in intravascular hemolysis and whether Nrf2 activation protected against hemoglobin (Hb)/heme-mediated renal damage in vivo and in vitro. We observed renal Nrf2 activation in human hemolysis and in an experimental model of intravascular hemolysis promoted by phenylhydrazine intraperitoneal injection. In wild-type mice, Hb/heme released from intravascular hemolysis promoted AKI, resulting in decreased renal function, enhanced expression of tubular injury markers (KIM-1 and NGAL), oxidative and endoplasmic reticulum stress (ER), and cell death. These features were more severe in Nrf2-deficient mice, which showed decreased expression of Nrf2-related antioxidant enzymes, including heme oxygenase 1 (HO-1) and ferritin. Nrf2 activation with sulforaphane protected against Hb toxicity in mice and cultured tubular epithelial cells, ameliorating renal function and kidney injury and reducing cell stress and death. Nrf2 genotype or sulforaphane treatment did not influence the severity of hemolysis. In conclusion, our study identifies Nrf2 as a key molecule involved in protection against renal damage associated with hemolysis and opens novel therapeutic approaches to prevent renal damage in patients with severe hemolytic crisis. These findings provide new insights into novel aspects of Hb-mediated renal toxicity and may have important therapeutic implications for intravascular hemolysis-related diseases.

Pharmacological doses of melatonin impede cognitive decline in tau-related Alzheimer models, once tauopathy is initiated, by restoring the autophagic flux.

Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV-hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau-related models. Melatonin (10 µmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV-hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase-3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD.

The angiotensin-(1-7)/Mas receptor axis protects from endothelial cell senescence via klotho and Nrf2 activation.

Endothelial cell senescence is a hallmark of vascular aging that predisposes to vascular disease. We aimed to explore the capacity of the renin-angiotensin system (RAS) heptapeptide angiotensin (Ang)-(1-7) to counteract human endothelial cell senescence and to identify intracellular pathways mediating its potential protective action. In human umbilical vein endothelial cell (HUVEC) cultures, Ang II promoted cell senescence, as revealed by the enhancement in senescence-associated galactosidase (SA-ß-gal+) positive staining, total and telomeric DNA damage, adhesion molecule expression, and human mononuclear adhesion to HUVEC monolayers. By activating the G protein-coupled receptor Mas, Ang-(1-7) inhibited the pro-senescence action of Ang II, but also of a non-RAS stressor such as the cytokine IL-1ß. Moreover, Ang-(1-7) enhanced endothelial klotho levels, while klotho silencing resulted in the loss of the anti-senescence action of the heptapeptide. Indeed, both Ang-(1-7) and recombinant klotho activated the cytoprotective Nrf2/heme oxygenase-1 (HO-1) pathway. The HO-1 inhibitor tin protoporphyrin IX prevented the anti-senescence action evoked by Ang-(1-7) or recombinant klotho. Overall, the present study identifies Ang-(1-7) as an anti-senescence peptide displaying its protective action beyond the RAS by consecutively activating klotho and Nrf2/HO-1. Ang-(1-7) mimetic drugs may thus prove useful to prevent endothelial cell senescence and its related vascular complications.

MAFG is a potential therapeutic target to restore chemosensitivity in cisplatin-resistant cancer cells by increasing reactive oxygen species.

Adjuvant chemotherapy for solid tumors based on platinum-derived compounds such as cisplatin is the treatment of choice in most cases. Cisplatin triggers signaling pathways that lead to cell death, but it also induces changes in tumor cells that modify the therapeutic response, thereby leading to cisplatin resistance. We have recently reported that microRNA-7 is silenced by DNA methylation and is involved in the resistance to platinum in cancer cells through the action of the musculoaponeurotic fibrosarcoma oncogene family, protein G (MAFG). In the present study, we first confirm the miR-7 epigenetic regulation of MAFG in 44 normal- and/or tumor-paired samples in non-small-cell lung cancer (NSCLC). We also provide translational evidence of the role of MAFG and the clinical outcome in NSCLC by the interrogation of two extensive in silico databases of 2019 patients. Moreover, we propose that MAFG-mediated resistance could be conferred due to lower reactive oxygen species production after cisplatin exposure. We developed specifically selected aptamers against MAFG, with high sensitivity to detect the protein at a nuclear level probed by aptacytochemistry and histochemistry analyses. The inhibition of MAFG activity through the action of the specific aptamer apMAFG6F increased the levels of reactive oxygen species production and the sensitivity to cisplatin. We report first the specific nuclear identification of MAFG as a novel detection method for diagnosis in NSCLC, and then we report that MAFG modulates the redox response and confers cell protection against free radicals generated after platinum administration, thus also being a promising therapeutic target.