Elastase-2 Knockout Mice Display Anxiogenic- and Antidepressant-Like Phenotype : Putative Role for BDNF Metabolism in Prefrontal Cortex

Several pieces of evidence indicate that elastase-2 (ELA2; chymotrypsin-like ELA2) is an alternative pathway to the generation of angiotensin II (ANGII). Elastase-2 knockout mice (ELA2KO) exhibit alterations in the arterial blood pressure and heart rate. However, there is no data on the behavioral consequences of ELA2 deletion. In this study, we addressed this question, submitting ELA2KO and wild-type (WT) mice to several models sensitive to anxiety- and depression-like, memory, and repetitive behaviors. Our data indicates a higher incidence of barbering behavior in ELA2KO compared to WT, as well as an anxiogenic phenotype, evaluated in the elevated plus maze (EPM). While a decrease in locomotor activity was observed in ELA2KO in EPM, this feature was not the main source of variation in the other parameters analyzed. The marble-burying test (MBT) indicated increase in repetitive behavior, observed by a higher number of buried marbles. The actimeter test indicated a decrease in total activity and confirmed the increase in repetitive behavior. The spatial memory was tested by repeated exposure to the actimeter in a 24-h interval. Both ELA2KO and WT exhibited decreased activity compared to the first exposure, without any distinction between the genotypes. However, when submitted to the cued fear conditioning, ELA2KO displayed lower levels of freezing behavior in the extinction session when compared to WT, but no difference was observed during the conditioning phase. Increased levels of BDNF were found in the prefrontal cortex but not in the hippocampus of ELA2KO mice compared to WT. Finally, in silico analysis indicates that ELA2 is putatively able to cleave BDNF, and incubation of the purified enzyme with BDNF led to the degradation of the latter. Our data suggested an anxiogenic- and antidepressant-like phenotype of ELA2KO, possibly associated with increased levels of BDNF in the prefrontal cortex.Peer reviewe

The role of extracellular vesicles in the removal of aggregated TDP43 responsible for ALS/FTD diseases

Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) are two related neurodegenerative diseases. ALS is caused by the death of both upper and lower motoneurons, while FTD is characterized predominantly by circumscribed atrophy of the frontal and temporal lobes. ALS and FTD overlap each other. This is demonstrated by the presence of cognitive and behavioral dysfunction in up to 50% of ALS patients and by the presence of frontotemporal atrophy in patients with ALS. Moreover, these diseases are both characterize by the presence of TAR DNA binding protein 43 (TDP43) inclusions in affected cells. These inclusions, observed in 97% of patients with ALS and 50% of patients with FTD, are composed by TDP43 and its C-terminal fragments of 35 kDa (TDP35) and 25 kDa (TDP25). These fragments are highly aggregation-prone and probably neurotoxic. Thus, their removal is protective for cells. The mechanism responsible for the clearance of aggregates and misfolded proteins is the intracellular protein quality control (PQC) system. It consists of molecular chaperones/co- chaperones and the degradative pathways. PQC controls the folding status of proteins and prevents the aggregation of misfolded proteins by refolding them or degrading. Recent data demonstrated that also extracellular secretory pathway, represented especially by exosomes (EXOs) and microvesicles (MVs), might be involved in the removal of misfolded proteins from affected cells. Thus, we evaluated the role of EXOs and MVs in the secretion of TDP43 and its C-terminal fragments, using neuronal cell models. We used ultracentrifugation, that allowed us to separate MVs from EXOs on the basis of their dimension. Then we analyzed them through i) Nanoparticle Tracking Analysis (NanoSight) to establish their number and sizes, and ii) western blot analysis, to characterize their protein content. Our preliminary results show that TDP43, TDP35 and TDP25 are all secreted, mainly by MVs. In particular, we found that MVs are enriched of insoluble forms of TDPs and also of superoxide dismutase 1 (SOD1), another ALS-related protein. Finally, both in EXOs and in MVs, we observed the presence of some important PQC-components, suggesting an interplay between the two pathways. GRANTS: Fondazione Cariplo, Italy (n. 2017_0747); Universit\ue0 degli Studi di Milano e piano di sviluppo UNIMI - linea B

Enhanced Clearance of Neurotoxic Misfolded Proteins by the Natural Compound Berberine and Its Derivatives

Background: Accumulation of misfolded proteins is a common hallmark of several neurodegenerative disorders (NDs) which results from a failure or an impairment of the proteinquality control (PQC) system. The PQC system is composed by chaperones and the degradative systems (proteasome and autophagy). Mutant proteins that misfold are potentially neurotoxic, thus strategies aimed at preventing their aggregation or at enhancing their clearance are emerging as interesting therapeutic targets for NDs. Methods: We tested the natural alkaloid berberine (BBR) and some derivatives for their capability to enhance misfolded protein clearance in cell models of NDs, evaluating which degradative pathway mediates their action. Results: We found that both BBR and its semisynthetic derivatives promote degradation of mutant androgen receptor (ARpolyQ) causative of spinal and bulbar muscular atrophy, acting mainly via proteasome and preventing ARpolyQ aggregation. Overlapping effects were observed on other misfolded proteins causative of amyotrophic lateral sclerosis, frontotemporal-lobar degeneration or Huntington disease, but with selective and specific action against each different mutant protein. Conclusions: BBR and its analogues induce the clearance of misfolded proteins responsible for NDs, representing potential therapeutic tools to counteract these fatal disorders

Eficácia de herbicidas pré-emergentes no controle de caruru resistente ao glifosato e efeito carryover sobre azevém em sucessão.

O objetivo do trabalho foi investigar o efeito residual de herbicidas pré-emergentes no controle de caruru e o efeito carryover sobre azevém em sucessão ao cultivo de soja

Eficiência de fungicidas para controle de giberela do trigo: resultados dos ensaios cooperativos, safra 2020.

A giberela, causada por Gibberella zea (Schw) Petch. (anamorfo Fusarium graminearum Schwabe), está presente em todos os continentes, sendo considerada a principal doença da espiga do trigo. Isso se deve por seu elevado potencial de perdas, isto é, a doença giberela causa danos significativos na espiga, afetando diretamente a quantidade e a qualidade dos grãos ou sementes pela produção da micotoxina desoxinivalenol (DON) (Fernandes; Tibola, 2011; Lau et al., 2011). A giberela em trigo é considerada uma doença de infecção floral e de difícil controle. Pode ocorrer a partir do espigamento, sendo altamente influenciada pelo ambiente. Os sintomas característicos são espiguetas esbranquiçadas e aristas que se desviam do sentido das aristas de espiguetas sadias.ODS 2, ODS 1

Pathogenic variants of Valosin-containing protein induce lysosomal damage and transcriptional activation of autophagy regulators in neuronal cells

Aim: Mutations in the valosin-containing protein (VCP) gene cause various lethal proteinopathies that mainly include inclusion body myopathy with Paget's disease of bone and frontotemporal dementia (IBMPFD) and amyotrophic lateral sclerosis (ALS). Different pathological mechanisms have been proposed. Here, we define the impact of VCP mutants on lysosomes and how cellular homeostasis is restored by inducing autophagy in the presence of lysosomal damage. Methods: By electron microscopy, we studied lysosomal morphology in VCP animal and motoneuronal models. With the use of western blotting, real-time quantitative polymerase chain reaction (RT-qPCR), immunofluorescence and filter trap assay, we evaluated the effect of selected VCP mutants in neuronal cells on lysosome size and activity, lysosomal membrane permeabilization and their impact on autophagy. Results: We found that VCP mutants induce the formation of aberrant multilamellar organelles in VCP animal and cell models similar to those found in patients with VCP mutations or with lysosomal storage disorders. In neuronal cells, we found altered lysosomal activity characterised by membrane permeabilization with galectin-3 redistribution and activation of PPP3CB. This selectively activated the autophagy/lysosomal transcriptional regulator TFE3, but not TFEB, and enhanced both SQSTM1/p62 and lipidated MAP1LC3B levels inducing autophagy. Moreover, we found that wild type VCP, but not the mutants, counteracted lysosomal damage induced either by trehalose or by a mutant form of SOD1 (G93A), also blocking the formation of its insoluble intracellular aggregates. Thus, chronic activation of autophagy might fuel the formation of multilamellar bodies. Conclusion: Together, our findings provide insights into the pathogenesis of VCP-related diseases, by proposing a novel mechanism of multilamellar body formation induced by VCP mutants that involves lysosomal damage and induction of lysophagy

Comparison of single- or multi-active ingredient fungicides for controlling Fusarium head blight and deoxynivalenol in Brazilian wheat.

In this study, we gathered data on Fusarium head blight (FHB) severity, deoxynivalenol (DON), and wheat yields from 19 cooperative fungicide trials conducted in Southern Brazil over five growing seasons (2017?2021). We tested three premixes of Quinone Outside Inhibitors (QoIs) + demethylation inhibitors (DMIs) (PYRAclostrobin + METConazole, TEBUconazole + TriFLoXystrobin, and TriFLoXystrobin + PROThioconazole), one triple premix of QoI + DMI + succinate dehydrogenase inhibitors (SDHI) (TriFLoXystrobin + PROThioconazole + BIXaFen), and two single active ingredients (METC [DMI] and CARBendazim [benzimidazole; MBC]) applied three times, beginning at the flowering stage and continuing every 7?12 days. We fitted a network meta-analysis model to the log of the means of FHB index and DON content data and to the non-transformed mean yield for each treatment, including the untreated control. Disease (FHB index) reduction estimates ranged from 41.5% (TEBU + TFLX) to 62.8% (METC); the latter did not differ from PYRA + METC (56.1%). Likewise, the mean estimates of percent DON reduction were higher for METC (65.1%) and PYRA + METC (58.3%). These two treatments were followed by TEBU + TFLX (50%), which was not statistically different from CARB (48%) and TFLX + PROT (45.2%), but differed from TFLX + PROT + BIXF (39.3%). Lastly, the yield response was higher for TFLX + PROT + BIXF (643 kg/ha), which differed from all other treatments, including METC (505.9 kg/ha), PYRA + METC (477.8 kg/ha), TFLX + PROT (455.3 kg/ha), CARB (453.2 kg/ha), and TEBU + TFLX (403.4 kg/ha). The results of this meta-analysis are crucial for choosing fungicides when planning programs aimed at reducing both FHB and DON levels in wheat

Rapid-acting antidepressants and the regulation of TrkB neurotrophic signalling-Insights from ketamine, nitrous oxide, seizures and anaesthesia

Increased glutamatergic neurotransmission and synaptic plasticity in the prefrontal cortex have been associated with the rapid antidepressant effects of ketamine. Activation of BDNF (brain-derived neurotrophic factor) receptor TrkB is considered a key molecular event for antidepressant-induced functional and structural synaptic plasticity. Several mechanisms have been proposed to underlie ketamine's effects on TrkB, but much remains unclear. Notably, preliminary studies suggest that besides ketamine, nitrous oxide (N2O) can rapidly alleviate depressive symptoms. We have shown nitrous oxide to evoke TrkB signalling preferentially after the acute pharmacological effects have dissipated (ie after receptor disengagement), when slow delta frequency electroencephalogram (EEG) activity is up-regulated. Our findings also demonstrate that various anaesthetics and sedatives activate TrkB signalling, further highlighting the complex mechanisms underlying TrkB activation. We hypothesize that rapid-acting antidepressants share the ability to regulate TrkB signalling during homeostatically evoked slow-wave activity and that this mechanism is important for sustained antidepressant effects. Our observations urge the examination of rapid and sustained antidepressant effects beyond conventional receptor pharmacology by focusing on brain physiology and temporally distributed signalling patterns spanning both wake and sleep. Potential implications of this approach for the improvement of current therapies and discovery of novel antidepressants are discussed.Peer reviewe