Retinoic acid-induced survival effects in SH-SY5Y neuroblastoma cells.

Neuroblastoma is a malignant childhood cancer arising from the embryonic sympathoadrenal lineage of the neural crest. Retinoic acid (RA) is included in the multimodal therapy of patients with high-risk neuroblastoma to eliminate minimal residual disease. However, the formation of RA-resistant cells substantially lowers 5-year overall survival rates. To examine mechanisms that lead to treatment failure, we chose human SH-SY5Y cells, which are known to tolerate incubation with RA by activating the survival kinases Akt and extracellular signal-regulated kinase 1/2. Characterization of downstream pathways showed that both kinases increased the phosphorylation of the ubiquitin ligase mouse double minute homolog 2 (Mdm2) and thereby enhanced p53 degradation. When p53 signaling was sustained by blocking complex formation with Mdm2 or enhancing c-Jun N-terminal kinase (JNK) activation, cell viability was significantly reduced. In addition, Akt-mediated phosphorylation of the cell-cycle regulator p21 stimulated complex formation with caspase-3, which also contributed to cell protection. Thus, treatment with RA augmented survival signaling and attenuated basal apoptotic pathways in SH-SY5Y cells, which increased cell viability.

Miswiring the brain: Δ9-tetrahydrocannabinol disrupts cortical development by inducing an SCG10/stathmin-2 degradation pathway.

Children exposed in utero to cannabis present permanent neurobehavioral and cognitive impairments. Psychoactive constituents from Cannabis spp., particularly Δ(9)-tetrahydrocannabinol (THC), bind to cannabinoid receptors in the fetal brain. However, it is unknown whether THC can trigger a cannabinoid receptor-driven molecular cascade to disrupt neuronal specification. Here, we show that repeated THC exposure disrupts endocannabinoid signaling, particularly the temporal dynamics of CB1 cannabinoid receptor, to rewire the fetal cortical circuitry. By interrogating the THC-sensitive neuronal proteome we identify Superior Cervical Ganglion 10 (SCG10)/stathmin-2, a microtubule-binding protein in axons, as a substrate of altered neuronal connectivity. We find SCG10 mRNA and protein reduced in the hippocampus of midgestational human cannabis-exposed fetuses, defining SCG10 as the first cannabis-driven molecular effector in the developing cerebrum. CB1 cannabinoid receptor activation recruits c-Jun N-terminal kinases to phosphorylate SCG10, promoting its rapid degradation in situ in motile axons and microtubule stabilization. Thus, THC enables ectopic formation of filopodia and alters axon morphology. These data highlight the maintenance of cytoskeletal dynamics as a molecular target for cannabis, whose imbalance can limit the computational power of neuronal circuitries in affected offspring.

Crosstalk control and limits of physiological c-Jun N-terminal kinase activity for cell viability and neurite stability in differentiated PC12 cells.

The c-Jun N-terminal kinases (JNKs) are important mediators of cell viability and structural integrity in postmitotic neurons, which is required for maintaining synaptic connections and neural plasticity. In the present study, we chose differentiated PC12 cells as a well-characterised neuronal model system to selectively examine the regulation of basal JNK activity by extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt. We detected a complex interaction between the kinases to prevent cell death and neurite loss. Especially the appropriate level of JNK activation determined cellular survival. Basal activity of ERK1/2 attenuated the potentiation of JNK phosphorylation and thereby the induction of apoptosis. Importantly, when JNK activity was too low, cell viability and the number of neurite-bearing cells also decreased, even though the activation of ERK1/2 was enhanced. In this case, the JNK-mediated survival signals via activating transcription factor-3 (ATF3) were inhibited. Furthermore, the phosphorylation of ERK1/2 induced by the JNK inhibitor SP600125 inhibited the basal activity of Akt, which normally supported cell viability. Thus, controlling JNK activity is crucial to promote survival and neurite stability of differentiated neuronal cells.

Virus-free and cured? The "ART" of adherence. Current efficacy of anti-HIV therapy. / Virusfrei und geheilt? Die Kunst (ART) der Adhärenz Zur aktuellen Wirksamkeit der antiretroviralen HIV-Therapie

The antiretroviral therapy (ART) enables an almost normal life with HIV infection. Does this also hold true for sexual intercourse, i.e. safe sex without condoms? The European PARTNER-study provides evidence for a very low risk of transmission for condomless sex under optimized conditions such as early, adherent and lasting ART (<200 RNA copies/ml) as well as stable partnerships. The risk of transmission is enhanced with non-compliance or shortlasting (< 6 months) ART, increased HIV-1 RNA load and frequent partnerships.

Map2k4δ - identification and functional characterization of a novel Map2k4 splice variant.

Mitogen-activated protein kinase kinase 4 (Map2k4) is a dual specificity serin/threonine protein kinase that is unique among all MAP2Ks in activating two different subfamilies of mitogen-activated protein kinases, the c-Jun N-terminal kinases (JNKs) and p38 kinases. Map2k4 is essential during embryogenesis and involved in a variety of physiological and pathological processes. However, studies on its role in cancer development revealed partially conflicting data. In the present study, we report the identification of a novel splice variant of Map2k4, Map2k4δ, with an additional exon in front of the substrate binding D-domain. Map2k4δ is expressed together with Map2k4 in various tissues from rat, mouse and human. In PC12 cells, both splice variants control cell cycle progression and basal apoptosis by using different signaling pathways. If expression and activation of Map2k4 and Map2k4δ are at a certain, cell type-specific equilibrium, an appropriate cell growth is ensured. Overexpression of one kinase disrupts the intricate balance and either results in a highly proliferative or pro-apoptotic phenotype, partially reflecting the discrepancies in the literature on Map2k4 and its role in tumor development. Our findings contribute to the understanding of previous studies and point out that Map2k4 has not always a definite function, but rather triggers a cellular reaction in concert with other modulators.

Tyrphostin AG126 exerts neuroprotection in CNS inflammation by a dual mechanism.

The putative protein tyrosine kinase (PTK) inhibitor tyrphostin AG126 has proven beneficial in various models of inflammatory disease. Yet molecular targets and cellular mechanisms remained enigmatic. We demonstrate here that AG126 treatment has beneficial effects in experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. AG126 alleviates the clinical symptoms, diminishes encephalitogenic Th17 differentiation, reduces inflammatory CNS infiltration as well as microglia activation and attenuates myelin damage. We show that AG126 directly inhibits Bruton's tyrosine kinase (BTK), a PTK associated with B cell receptor and Toll-like receptor (TLR) signaling. However, BTK inhibition cannot account for the entire activity spectrum. Effects on TLR-induced proinflammatory cytokine expression in microglia involve AG126 hydrolysis and conversion of its dinitrile side chain to malononitrile (MN). Notably, while liberated MN can subsequently mediate critical AG126 features, full protection in EAE still requires delivery of intact AG126. Its anti-inflammatory potential and especially interference with TLR signaling thus rely on a dual mechanism encompassing BTK and a novel MN-sensitive target. Both principles bear great potential for the therapeutic management of disturbed innate and adaptive immune functions.

TNF-induced necroptosis and PARP-1-mediated necrosis represent distinct routes to programmed necrotic cell death.

Programmed necrosis is important in many (patho)physiological settings. For specific therapeutic intervention, however, a better knowledge is required whether necrosis occurs through one single "core program" or through several independent pathways. Previously, the poly(ADP-ribose) polymerase (PARP) pathway has been suggested as a crucial element of tumor necrosis factor (TNF)-mediated necroptosis. Here, we show that TNF-induced necroptosis and the PARP pathway represent distinct and independent routes to programmed necrosis. First, DNA-alkylating agents such as 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) or methyl methanesulfonate rapidly activate the PARP pathway, whereas this is a late and secondary event in TNF-induced necroptosis. Second, inhibition of the PARP pathway does not protect against TNF-induced necroptosis, e.g., the PARP-1 inhibitor 3-AB prevented MNNG- but not TNF-induced adenosine-5'-triposphate depletion, translocation of apoptosis-inducing factor, and necrosis. Likewise, olaparib, a more potent and selective PARP-1 inhibitor failed to block TNF-induced necroptosis, identical to knockdown/knockout of PARP-1, pharmacologic and genetic interference with c-Jun N-terminal kinases and calpain/cathepsin proteases as further components of the PARP pathway. Third, interruption of TNF-induced necroptosis by interference with ceramide generation, RIP1 or RIP3 function or by the radical scavenger butylated hydroxyanisole did not prevent programmed necrosis through the PARP pathway. In summary, our results suggest that the currently established role of the PARP pathway in TNF-induced necroptosis needs to be revised, with consequences for the design of future therapeutic strategies.

Mitochondrial gene polymorphisms that protect mice from colitis.

BACKGROUND & AIMS: Dysregulated energy homeostasis in the intestinal mucosa frequently is observed in patients with ulcerative colitis (UC). Intestinal tissues from these patients have reduced activity of the mitochondrial oxidative phosphorylation (OXPHOS) complex, so mitochondrial dysfunction could contribute to the pathogenesis of UC. However, little is known about the mechanisms by which OXPHOS activity could be altered. We used conplastic mice, which have identical nuclear but different mitochondrial genomes, to investigate activities of the OXPHOS complex. METHODS: Colitis was induced in C57BL/6J wild-type (B6.B6) and 3 strains of conplastic mice (B6.NZB, B6.NOD, and B6.AKR) by administration of dextran sodium sulfate or rectal application of trinitrobenzene sulfonate. Colon tissues were collected and analyzed by histopathology, immunohistochemical analysis, and immunoblot analysis; we also measured mucosal levels of adenosine triphosphate (ATP) and reactive oxygen species, OXPHOS complex activity, and epithelial cell proliferation and apoptosis. RESULTS: We identified mice with increased mucosal OXPHOS complex activities and levels of ATP. These mice developed less-severe colitis after administration of dextran sodium sulfate or trinitrobenzene sulfonate than mice with lower mucosal levels of ATP. Colon tissues from these mice also had increased enterocyte proliferation and transcription factor nuclear factor-κB activity, which have been shown to protect the mucosal barrier-defects in these processes have been associated with inflammatory bowel disease. CONCLUSIONS: Variants in mitochondrial DNA that increase mucosal levels of ATP protect mice from colitis. Increasing mitochondrial ATP synthesis in intestinal epithelial cells could be a therapeutic approach for UC.

Hyperthermia differently affects connexin43 expression and gap junction permeability in skeletal myoblasts and HeLa cells.

Stress kinases can be activated by hyperthermia and modify the expression level and properties of membranous and intercellular channels. We examined the role of c-Jun NH2-terminal kinase (JNK) in hyperthermia-induced changes of connexin43 (Cx43) expression and permeability of Cx43 gap junctions (GJs) in the rabbit skeletal myoblasts (SkMs) and Cx43-EGFP transfected HeLa cells. Hyperthermia (42°C for 6 h) enhanced the activity of JNK and its target, the transcription factor c-Jun, in both SkMs and HeLa cells. In SkMs, hyperthermia caused a 3.2-fold increase in the total Cx43 protein level and enhanced the efficacy of GJ intercellular communication (GJIC). In striking contrast, hyperthermia reduced the total amount of Cx43 protein, the number of Cx43 channels in GJ plaques, the density of hemichannels in the cell membranes, and the efficiency of GJIC in HeLa cells. Both in SkMs and HeLa cells, these changes could be prevented by XG-102, a JNK inhibitor. In HeLa cells, the changes in Cx43 expression and GJIC under hyperthermic conditions were accompanied by JNK-dependent disorganization of actin cytoskeleton stress fibers while in SkMs, the actin cytoskeleton remained intact. These findings provide an attractive model to identify the regulatory players within signalosomes, which determine the cell-dependent outcomes of hyperthermia.

Ribavirin shows immunomodulatory effects on activated microglia.

Abstract Ribavirin (RBV) is synthetic purine nucleoside analogue, licensed as anti-viral drug that displays immunomodulatory actions on various immune cells. Our previous ex vivo studies have demonstrated immunosuppressive effects of RBV on reactive T-lymphocytes in experimental autoimmune encephalomyelitis. Here, we examined the effects of RBV on inflammatory response of microglia. RBV potency to down-regulate microglia inflammatory response was assessed by measuring microglia cell body size, and the production of nitric oxide (NO) and pro- and anti-inflammatory cytokines. RBV exerted cytotoxic effects on LPS-stimulated microglia, leaving non-stimulated microglia unaffected. The exposure of activated microglia to RBV led to: decrease in the level of NO as a result of decreased cell number, lower average cell surface, the reduction of membrane ruffling, the suppression of interleukin-6 release and promoted interleukin-10 production. On the other hand, RBV promoted LPS-induced interleukin-1 beta release. Our results imply that RBV is a complex immunomodulator showing both anti- and pro-inflammatory effects on activated microglia.

The Use of Tetrahydrocannabinol Is Associated with an Increase in Survival Time in Palliative Cancer Patients: A Retrospective Multicenter Cohort Study.

Introduction: Tetrahydrocannabinol (THC) is often prescribed for ambulatory palliative patients to improve sleep quality and appetite and to reduce anxiety, stress, and pain. However, it is not known if THC has also an effect on the mortality of these patients. Method: The objective was the impact of THC on mortality of ambulatory palliative patients. For this purpose, data from the palliative treatment documentation from 5 ambulatory palliative care teams in Brandenburg, Germany were used for this analysis. Survival time was calculated for 3 groups of patients: (1) without THC; (2) with THC in a low dosage (≤4.7 mg per day); and (3) THC in higher doses (≥4.7 mg per day). The analysis was done for 2 cohorts of patients. Cohort 1: all patients with a survival time of at least 7 days after inclusion in specialized ambulatory palliative care (SAPC) and cohort 2: a subgroup of patients with a survival time between 7 and 100 days. Kaplan-Meier curves were created, and multivariate analysis was done to investigate the impact of THC on mortality. Results: A total of 9,419 patients with a survival time of at least 7 days after inclusion in SAPC were included in the analysis (cohort 1). 7,085 among them had a survival time between 7 and 100 days (cohort 2). In both cohorts, survival time was significantly prolonged by THC, but only when the daily THC dose was above the median of 4.7 mg. Survival time was 15 days longer in cohort 2 (40 vs. 25 days), when more than 4.7 mg THC were prescribed per day. Conclusion: Use of THC is associated with a significant increase in survival time in ambulatory palliative patients which survive longer than 7 days the initiation of THC prescription and which use of THC >4.7 mg/day.

The JNK inhibitor D-JNKI-1 blocks apoptotic JNK signaling in brain mitochondria.

Kainic acid (KA) induced seizures provokes an extensive neuronal degeneration initiated by c-Jun N-terminal kinases (JNK) as central mediators of excitotoxicity. However, the actions of their individual isoforms in cellular organelles including mitochondria remain to be elucidated. Here, we have studied the activation of JNK1, JNK2 and JNK3 and their activators, mitogen-activated protein kinase kinase (MKK) 4/7, in brain mitochondria, cytosolic and nuclear fractions after KA seizures. In the mitochondrial fraction, KA significantly increased the presence of JNK1, JNK3 and MKK4 and stimulated their phosphorylation i.e. activation. The pro-apoptotic proteins, Bim and Bax were induced and, consequently, the ratio Bcl-2-Bax decreased. These changes were paralleled by the release of cytochrome c and cleavage of poly(ADP-ribose)-polymerase (PARP). The JNK peptide inhibitor, D-JNKI-1 (XG-102) reversed these pathological events in the mitochondria and almost completely abolished cytochrome c release and PARP cleavage. Importantly, JNK3, but not JNK1 or JNK2, was associated with Bim in mitochondria and D-JNKI-1 prevented the formation of this apoptotic complex. Apart from of the attenuation of c-Jun phosphorylation in the nucleus, D-JNKI-1 did not affect the level of JNK3 isoform in the nuclear and cytosolic fractions. These findings provide novel insights into the mode of action of individual JNK isoforms in cell organelles and points to the JNK3 pool in mitochondria as a target of the JNK inhibitor D-JNKI-1 to confer neuroprotection.

Drug Interactions of Tetrahydrocannabinol and Cannabidiol in Cannabinoid Drugs.

BACKGROUND: Cannabinoid drugs containing tetrahydrocannabinol (THC), or its structural analogues, as monotherapeutic agents or as extracts or botanical preparations with or without cannabidiol (CBD) are often prescribed to multimorbid patients who are taking multiple drugs. This raises the question of the risk of drug interactions. METHODS: This review of the pharmacokinetics and pharmacodynamics of interactions with cannabinoid drugs and their potential effects is based on pertinent publications retrieved by a selective literature search. RESULTS: As THC and CBD are largely metabolized in the liver, their bioavailability after oral or oral-mucosal administration is low (6-8% and 11-13%, respectively). The plasma concentrations of THC and its active metabolite 11-OH-THC can be increased by strong CYP3A4 inhibitors (verapamil, clarithromycin) and decreased by strong CYP3A4 inductors (rifampicin, carbamazepine). The clinical significance of these effects is unclear because of the variable plasma level and therapeutic spectrum of THC. The metabolism of CBD is less dependent on cytochrome P450 enzymes than that of THC. THC and CBD inhibit CYP2C and CYP3A4; the corresponding clinically relevant drug interactions probably are likely to arise only with THC doses above 30 mg/day and CBD doses above 300 mg/day. CONCLUSION: Potential drug interactions with THC and CBD are probably of little importance at low or moderate doses. Strong CYP inhibitors or inductors can intensify or weaken their effect. Slowly ramping up the dose of oral cannabinoid drugs can lessen their pharmacodynamic interactions, which can generally be well controlled. Administration by inhalation can worsen the interactions.

Nrf2 induces interleukin-6 (IL-6) expression via an antioxidant response element within the IL-6 promoter.

IL-6 gene expression is controlled by a promoter region containing multiple regulatory elements such as NF-κB, NF-IL6, CRE, GRE, and TRE. In this study, we demonstrated that TRE, found within the IL-6 promoter, is embedded in a functional antioxidant response element (ARE) matching an entire ARE consensus sequence. Further, point mutations of the ARE consensus sequence in the IL-6 promoter construct selectively eliminate ARE but not TRE activity. Nrf2 is a redox-sensitive transcription factor which provides cytoprotection against electrophilic and oxidative stress and is the most potent activator of ARE-dependent transcription. Using Nrf2 knock-out mice we demonstrate that Nrf2 is a potent activator of IL-6 gene transcription in vivo. Moreover, we show evidence that Nrf2 is the transcription factor that activates IL6 expression in a cholestatic hepatitis mouse model. Our findings suggest a possible role of IL-6 in oxidative stress defense and also give indication about an important function for Nrf2 in the regulation of hematopoietic and inflammatory processes.

Neuronal c-Jun is required for successful axonal regeneration, but the effects of phosphorylation of its N-terminus are moderate.

Although neural c-Jun is essential for successful peripheral nerve regeneration, the cellular basis of this effect and the impact of c-Jun activation are incompletely understood. In the current study, we explored the effects of neuron-selective c-Jun deletion, substitution of serine 63 and 73 phosphoacceptor sites with non-phosphorylatable alanine, and deletion of Jun N-terminal kinases 1, 2 and 3 in mouse facial nerve regeneration. Removal of the floxed c-jun gene in facial motoneurons using cre recombinase under control of a neuron-specific synapsin promoter (junΔS) abolished basal and injury-induced neuronal c-Jun immunoreactivity, as well as most of the molecular responses following facial axotomy. Absence of neuronal Jun reduced the speed of axonal regeneration following crush, and prevented most cut axons from reconnecting to their target, significantly reducing functional recovery. Despite blocking cell death, this was associated with a large number of shrunken neurons. Finally, junΔS mutants also had diminished astrocyte and microglial activation and T-cell influx, suggesting that these non-neuronal responses depend on the release of Jun-dependent signals from neighboring injured motoneurons. The effects of substituting serine 63 and 73 phosphoacceptor sites (junAA), or of global deletion of individual kinases responsible for N-terminal c-Jun phosphorylation were mild. junAA mutants showed decrease in neuronal cell size, a moderate reduction in post-axotomy CD44 levels and slightly increased astrogliosis. Deletion of Jun N-terminal kinase (JNK)1 or JNK3 showed delayed functional recovery; deletion of JNK3 also interfered with T-cell influx, and reduced CD44 levels. Deletion of JNK2 had no effect. Thus, neuronal c-Jun is needed in regeneration, but JNK phosphorylation of the N-terminus mostly appears to not be required for its function.

Transient filament occlusion of the middle cerebral artery in rats: does the reperfusion method matter 24 hours after perfusion?

BACKGROUND: There are two widely used transient middle cerebral artery occlusion (MCAO) methods, which differ in the use of unilateral or bilateral carotid artery reperfusion (UNICAR and BICAR). Of the two methods, UNICAR is easier to perform. This study was designed to comprehensively compare the two reperfusion methods to determine if there are any differences in outcomes. RESULTS: The UNICAR and BICAR groups each included 9 rats. At baseline, the average pO(2) was 20.54 ± 9.35 and 26.43 ± 7.39, for the UNICAR and BICAR groups, respectively (P = 0.519). Changes in pO(2), as well as other physiological parameters measured within the ischemic lesion, were similar between the UNICAR and BICAR groups during 90 min of MCAO and the first 30 min of reperfusion (all P > 0.05). Furthermore, both the Bederson score and Garcia score, which are used for neurological assessment, were also similar (both P > 0.05). There were also no significant differences in T2WI lesion volume, DWI lesion volume, PWI lesion volume, or TTC staining infarct volume between the two groups (all P > 0.05). CONCLUSION: UNICAR and BICAR have similar capability for inducing acute brain ischemic injury and can be considered interchangeable up to 24 hours after reperfusion.

JNK1 phosphorylation of SCG10 determines microtubule dynamics and axodendritic length.

c-Jun NH(2)-terminal kinases (JNKs) are essential during brain development, when they regulate morphogenic changes involving cell movement and migration. In the adult, JNK determines neuronal cytoarchitecture. To help uncover the molecular effectors for JNKs in these events, we affinity purified JNK-interacting proteins from brain. This revealed that the stathmin family microtubule-destabilizing proteins SCG10, SCLIP, RB3, and RB3' interact tightly with JNK. Furthermore, SCG10 is also phosphorylated by JNK in vivo on sites that regulate its microtubule depolymerizing activity, serines 62 and 73. SCG10-S73 phosphorylation is significantly decreased in JNK1-/- cortex, indicating that JNK1 phosphorylates SCG10 in developing forebrain. JNK phosphorylation of SCG10 determines axodendritic length in cerebrocortical cultures, and JNK site-phosphorylated SCG10 colocalizes with active JNK in embryonic brain regions undergoing neurite elongation and migration. We demonstrate that inhibition of cytoplasmic JNK and expression of SCG10-62A/73A both inhibited fluorescent tubulin recovery after photobleaching. These data suggest that JNK1 is responsible for regulation of SCG10 depolymerizing activity and neurite elongation during brain development.

Neuroprotective and antioxidative effects of pioglitazone in brain tissue adjacent to the ischemic core are mediated by PI3K/Akt and Nrf2/ARE pathways.

The present study elucidates the neuroprotective mechanisms of the PPARγ (peroxisome proliferator-activated receptor γ) agonist pioglitazone in survival of ischemic neurons following middle cerebral artery occlusion with reperfusion (MCAO). Intracerebroventricular infusion of pioglitazone over 5 days before and 24 or 48 h after MCAO alleviated neurological impairments, inhibited apoptosis 24 h, and activated the PI3K/Akt pathway along with increased phosphorylation of Akt (ser473) and GSK-3ß (ser9) in the peri-infarct cortical areas 48 h after MCAO. In primary cortical neurons, pioglitazone suppressed the glutamate-induced release of lactate dehydrogenase by a PPARγ-dependent mechanism. This protective effect was reversed after co-treatment with PI3K and Akt inhibitors, LY294002 and SH-6, respectively. Pioglitazone enhanced the expression of the antioxidative transcription factor Nrf2 and its target gene protein, heme oxidase-1, in the peri-infarct area. Pioglitazone also increased activation of the antioxidant response element (ARE) in neuronal PC12 cells transfected with the pNQO1-rARE plasmid. We demonstrate in primary cortical neurons from Nrf2 knockout mice that the lack of Nrf2 completely abolished the neuroprotective effects of pioglitazone against oxidative and excitotoxic damage. Our results strongly suggest that the neuroprotective effects of PPARγ in peri-infarct brain tissues comprise the concomitant activation of the PI3K/Akt and Nrf2/ARE pathways. KEY MESSAGES: Pioglitazone inhibits apoptosis in ischemic brain tissue.  Pioglitazone acting on PPARγ activates PI3K/Akt pathway in ischemic brain tissue. Pioglitazone activates via Nrf2 the antioxidant defense pathway in injured neurons. Pioglitazone activates the antioxidant response element in neuronal PC12 cells. Pioglitazone fails to protect primary neurons lacking Nrf2 against oxidative damage. Activation of PPARγ supports the survival of viable neurons in peri-infarct regions.

High-dose spironolactone lacks effectiveness in treatment of fibromyalgia (RCT).

BACKGROUND: Spironolactone (SPL) is a reversible mineralocorticoid receptor (MR) and androgen receptor (AR) antagonist which attracts pharmacotherapeutic interest not only because of its beneficial effects in heart failure but also because of the pathogenetic roles of MR and AR activities in neuropsychiatric diseases. Recently, beneficial and rapid-onset effects of SPL have been documented in a case series of women with fibromyalgia syndrome (FMS). To reaffirm this observation, we performed a double-blind placebo-controlled randomized clinical trial (RCT). METHODS: A total of 69 patients were screened, 56 patients were eligible and randomized to SPL or placebo (each n = 28). Forty-three patients completed the clinical trial to the last visit (n = 21 and n = 22). After a run-in phase of 50 and 100 mg/day, 200 mg/day SPL or placebo were applied between days 7 and 28. Primary outcome was the change in the FIQ-G score (Fibromyalgia Impact Questionnaire, German version). Secondary outcome parameters were the changes in pain (numeric rating scale, NRS), mood (ADS), quality of life (SF-36) and change in FIQ scores 14 days after the end of the medication. RESULTS: SPL of 200 mg/day did not change significantly either the primary or the secondary end points. SPL evoked a transient rise in serum potassium and a transient fall in GFR maximal after 2 weeks, but without clinical relevance. CONCLUSIONS: SPL at 200 mg/day does not improve symptoms in women with FMS, but was considered not to cause harm. SIGNIFICANCE: The mineralocorticoid receptor and androgen receptor antagonist spironolactone is repeatedly tested for its therapeutic effectivity against neuropsychiatric disorders. The present RCT demonstrated that 200 mg spironolactone does not change the symptoms of the fibromyalgia syndrome (FMS) in adult women. Between 2 and 4 weeks, spironolactone evokes a transient decrease in GFR and increase in serum potassium. Spironolactone cannot be recommended for the treatment of FMS.