Novel sulfoglycolipid IG20 causes neuroprotection by activating the phase II antioxidant response in rat hippocampal slices

Los datos de investigación asociados a este artículo están disponibles en http://dx.doi.org/10.1016/j.neuropharm.2016.12.016Compound IG20 is a newly synthesised sulphated glycolipid that promotes neuritic outgrowth and myelinisation, at the time it causes the inhibition of glial proliferation and facilitates exocytosis in chromaffin cells. Here we have shown that IG20 at 0.3–10 μM afforded neuroprotection in rat hippocampal slices stressed with veratridine, glutamate or with oxygen plus glucose deprivation followed by reoxygenation (OGD/reox). Excess production of reactive oxygen species (ROS) elicited by glutamate or ODG/reox was prevented by IG20 that also restored the depressed tissue levels of GSH and ATP in hippocampal slices subjected to OGD/reox. Furthermore, the augmented iNOS expression produced upon OGD/reox exposure was also counteracted by IG20. Additionally, the IG20 elicited neuroprotection was prevented by the presence of inhibitors of the signalling pathways Jak2/STAT3, MEK/ERK1/2, and PI3K/Akt, consistent with the ability of the compound to increase the phosphorylation of Jak2, ERK1/2, and Akt. Thus, the activation of phase II response and the Nrf2/ARE pathway could explain the antioxidant and anti-inflammatory effects and the ensuing neuroprotective actions of IG20This study was supported by a grant from Ministerio de Economía y Competitividad, Spain (MINECO SAF2013-44108-P to AGG and LG; MAT2015-65184-C2-2-R to AFM, CABICYC UAM-Bioiberica and European Commission-ERC, People (Marie Curie Actions) FP7 under REA grant agreement n PCIG11-GA-2012-322156; Spanish Ministry of Health (Instituto de Salud Carlos III) (grant PI14/00372) and Miguel Servet (CP11/00165); Bayer A.G., “From Targets to Novel Drugs” program (grant 2015-03-1282) and Fundacion FIPSE (grant 12-00001344-15) to RL. RL thanks IS Carlos III for research contract under Miguel Servet Program. P.M. thanks MECD for FPU fellowship (AP2010-1219

Implication of type 4 NADPH oxidase (NOX4) in tauopathy.

Aggregates of the microtubule-associated protein tau are a common marker of neurodegenerative diseases collectively termed as tauopathies, such as Alzheimer’s disease (AD) and frontotemporal dementia. Therapeutic strategies based on tau have failed in late stage clinical trials, suggesting that tauopathy may be the consequence of upstream causal mechanisms. As increasing levels of reactive oxygen species (ROS) may trigger protein aggregation or modulate protein degradation and, we had previously shown that the ROS producing enzyme NADPH oxidase 4 (NOX4) is a major contributor to cellular autotoxicity, this study was designed to evaluate if NOX4 is implicated in tauopathy. Our results show that NOX4 is upregulated in patients with frontotemporal lobar degeneration and AD patients and, in a humanized mouse model of tauopathy induced by AVV-TauP301L brain delivery. Both, global knockout and neuronal knockdown of the Nox4 gene in mice, diminished the accumulation of pathological tau and positively modified established tauopathy by a mechanism that implicates modulation of the autophagy-lysosomal pathway (ALP) and, consequently, improving the macroautophagy flux. Moreover, neuronal-targeted NOX4 knockdown was sufficient to reduce neurotoxicity and prevent cognitive decline, even after induction of tauopathy, suggesting a direct and causal role for neuronal NOX4 in tauopathy. Thus, NOX4 is a previously unrecognized causative, mechanism-based target in tauopathies and blood-brain barrier permeable specific NOX4 inhibitors could have therapeutic potential even in established disease.post-print5895 K

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 multi- target-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.The authors gratefully acknowledge the following financial supports: the Spanish Ministry of Science, Innovation and Universities; Spanish Research Agency; European Regional Development Funds (grants RTI2018-093955-B-C21, SAF2015-64948-C2-1-R, and PID2021-122650OB-I00 to M.I.R.-F.; RTI2018-095793-B-I00 to M.G.L.); Spanish Na- tional Research Council (CSIC grants, PIE-202080E118 to M.I.R.-F. and PIE-202080I026 to R.L.); Health Institute Carlos III (grant PI17/01700 to R.L.); and General Council for Research and Innovation of the Community of Madrid and European Structural Funds (grant B2017/BMD-3827- NRF24ADCM). They thank the Ministry of Education of Spain for the following fellowships: FPU16/01704 and mobility grant FPUEST17/00233 (to C.H.-A.), FPU15/ 03269 (to C.F.-M.), FPU18/00630 (to E.d.S.), and FPU13/ 03737 (to P.M.). R.L. and M.G.L. also thank “Fundación Teófilo Hernando” for its continued support. The Spanish Medicinal Chemistry Society (SEQT) awarded the “Lilly Prize for Young Researchers” to this work, presented by C.H.-A. at the XIX SEQT Awards.Peer reviewe

Modulación de la enzima hemo oxigenasa I (HO-1) microglial para el tratamiento de enfermedades neurodegenerativas

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Farmacología. Fecha de lectura: 01-07-2021Esta tesis tiene embargado el acceso al texto completo hasta el 01-01-2023Aging is the primary risk factor for the development of neurodegenerative diseases (NDDs), such as Alzheimer’s Disease (AD). However, oxidative stress (OS), aberrant protein aggregates and neuroinflammation have been identified as common pathophysiological markers in NDDs. In the specific case of AD, neuroinflammation is a key player starting in early stages of the disease. Moreover, intracellular neurofibrillary tangles (NFTs) and extracellular senile plaques, consequence of misfolded aberrant amyloid beta (Aβ) protein, are the specific protein aggregates characteristic in AD. Therefore, strategies aiming at modulating neuroinflammation and the formation of aberrant aggregates have gained interest. In this context, the enzyme HO-1 has been proposed as a promising therapeutic target as its activity is linked to anti-inflammatory and anti-oxidant effects. However, the expression pattern of HO-1 and its effects with aging and AD remain controversial. First, to elucidate the brain expression pattern of HO-1 with aging and AD, wild type (WT) and the 5xFAD (five familial AD mutations) mouse model of AD were used at different ages (4, 8, 12 and 18 months). The results from this Doctoral Thesis showed that total brain expression of HO-1 was increased with aging and in AD progression. Interestingly, this HO-1 up-regulation was mainly detected in microglial cells, which are the innate immune cells of the central nervous system (CNS). These findings were corroborated in human postmortem brain samples of AD patients, where HO-1 overexpression was also primarily detected in microglial cells when compared to other CNS cell types. Moreover, microglia overexpressing HO-1 was predominately located surrounding Aβ plaques in the mouse AD model. These findings highlight HO-1 as a potential biomarker or therapeutic target for the treatment of AD. However, whether this up-regulation was a compensatory mechanism to confront the subjacent neuroinflammation or was related to disease progression is still unknown. Therefore, we aimed at studying the effects of microglial HO-1 under inflammatory conditions, both in adult and aged mice. For this purpose, WT and LysMCreHmox1△△ (HMOX1M-KO) mice that lack HO-1 in microglial cells were used. In physiological conditions (adult mice), microglial HO-1 deletion after an inflammatory insult was linked to increased neuroinflammation, OS, cell death and behavioral alterations. However, in aged mice, where microglial HO-1 expression was already significantly up-regulated, the activity of this enzyme after an inflammatory insult was linked to increased levels of iron deposits and thus, augmented OS, neuroinflammation, cell death and cognitive decline. Our results show that both neuroprotective and neurodystrophic actions can be linked to microglial HO-1 activity. Therefore, strategies aiming at modulating HO-1 should be differently considered with regard to the basal expression of this enzyme to achieve beneficial outcome

Aging and Progression of Beta-Amyloid Pathology in Alzheimer's Disease Correlates with Microglial Heme-Oxygenase-1 Overexpression.

Neuroinflammation and oxidative stress are being recognized as characteristic hallmarks in many neurodegenerative diseases, especially those that portray proteinopathy, such as Alzheimer's disease (AD). Heme-oxygenase 1 (HO-1) is an inducible enzyme with antioxidant and anti-inflammatory properties, while microglia are the immune cells in the central nervous system. To elucidate the brain expression profile of microglial HO-1 in aging and AD-progression, we have used the 5xFAD (five familial AD mutations) mouse model of AD and their littermates at different ages (four, eight, 12, and 18 months). Total brain expression of HO-1 was increased with aging and such increase was even higher in 5xFAD animals. In co-localization studies, HO-1 expression was mainly found in microglia vs. other brain cells. The percentage of microglial cells expressing HO-1 and the amount of HO-1 expressed within microglia increased progressively with aging. Furthermore, this upregulation was increased by 2-3-fold in the elder 5xFAD mice. In addition, microglia overexpressing HO-1 was predominately found surrounding beta-amyloid plaques. These results were corroborated using postmortem brain samples from AD patients, where microglial HO-1 was found up-regulated in comparison to brain samples from aged matched non-demented patients. This study demonstrates that microglial HO-1 expression increases with aging and especially with AD progression, highlighting HO-1 as a potential biomarker or therapeutic target for AD

Aging and Progression of Beta-Amyloid Pathology in Alzheimer's Disease Correlates with Microglial Heme-Oxygenase-1 Overexpression.

Neuroinflammation and oxidative stress are being recognized as characteristic hallmarks in many neurodegenerative diseases, especially those that portray proteinopathy, such as Alzheimer's disease (AD). Heme-oxygenase 1 (HO-1) is an inducible enzyme with antioxidant and anti-inflammatory properties, while microglia are the immune cells in the central nervous system. To elucidate the brain expression profile of microglial HO-1 in aging and AD-progression, we have used the 5xFAD (five familial AD mutations) mouse model of AD and their littermates at different ages (four, eight, 12, and 18 months). Total brain expression of HO-1 was increased with aging and such increase was even higher in 5xFAD animals. In co-localization studies, HO-1 expression was mainly found in microglia vs. other brain cells. The percentage of microglial cells expressing HO-1 and the amount of HO-1 expressed within microglia increased progressively with aging. Furthermore, this upregulation was increased by 2-3-fold in the elder 5xFAD mice. In addition, microglia overexpressing HO-1 was predominately found surrounding beta-amyloid plaques. These results were corroborated using postmortem brain samples from AD patients, where microglial HO-1 was found up-regulated in comparison to brain samples from aged matched non-demented patients. This study demonstrates that microglial HO-1 expression increases with aging and especially with AD progression, highlighting HO-1 as a potential biomarker or therapeutic target for AD

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.This work was supported by grants from IS Carlos III co-financed by the European Regional Development’s funds (FEDER), Programa Miguel Servet II (CP16/00014) and research project (grant PI17/01700) to RL; Fundación La Caixa, CaixaImpulse program (grant CI17-00048) to RL; Comunidad Autónoma de Madrid (grant B2017/BMD-3827) and Spanish Ministry of Science, Innovation and Education (grant RTI2018-095793-B-I00) to MGL. P.M., P.D. and C.F.-M thanks MECD for FPU fellowships (13/0373716/03977 and 15/03269 respectively). I.B thanks MECD for Juan de la Cierva fellowship (FJCI-2016/28282). We would also like to thank “Fundación Teófilo Hernando” for its continued support.Peer reviewe

Multitarget compounds for the treatment of neurodegenerative diseases: Nrf2-EpRE pathway as key target

Resumen del trabajo presentado al 1st PhD Research Symposium in Health Sciences and Biomedicine, celebrado en la Universidad Autónoma de Madrid el 18 de mayo de 2018.IS Carlos III (Contrato Miguel Servet II a RL, proyecto CPII16/00014 y proyecto PI14/00372 a RL),). Ministerio de Educación, Cultura y Deporte (MECD) FPU13/03737 a P.M, FPU16/03977 a P.D.Peer reviewe

1-(2′,5′-dihydroxyphenyl)-3-(2-fluoro-4-hydroxyphenyl)-1-propanone (RGM079): A positive allosteric modulator of α7 nicotinic receptors with analgesic and neuroprotective activity

Acetylcholine α7 nicotinic receptors are widely expressed in the brain, where they are involved in the central processing of pain as well as in neuropsychiatric, neurodegenerative, and inflammatory processes. Positive allosteric modulators (PAMs) show the advantage of allowing the selective regulation of different subtypes of acetylcholine receptors without directly interacting with the agonist binding site. Here, we report the preparation and biological activity of a fluoro-containing compound, 1-(2′,5′-dihydroxyphenyl)-3-(2-fluoro-4-hydroxyphenyl)-1-propanone (8, RGM079), that behaves as a potent PAM of the α7 receptors and has a balanced pharmacokinetic profile and antioxidant properties comparable or even higher than well-known natural polyphenols. In addition, compound RGM079 shows neuroprotective properties in Alzheimer's disease (AD)-toxicity related models. Thus, it causes a concentration-dependent neuroprotective effect against the toxicity induced by okadaic acid (OA) in the human neuroblastoma cell line SH-SY5Y. Similarly, in primary cultures of rat cortical neurons, RGM079 is able to restore the cellular viability after exposure to OA and amyloid peptide Aβ, with cell death almost completely prevented at 10 and 30 μM, respectively. Finally, compound RGM079 shows in vivo analgesic activity in the complete Freund's adjuvant (CFA)-induced paw inflammation model after intraperitoneal administration.This work was supported by grants from the Spanish Ministerio de Economía y Competitividad (MINECO-FEDER) grant number SAF2015-66275-C2-R and RTI2018-097189-C2 to RGM and AFM, and RTI2018-095793-B-I00 to MGL, the Comunidad de Madrid/European Union Ref S2017/BMD-3827 to MGL and the CSIC, grant number 201980E030 to RGM