A 13-week dietary toxicity study in rats of a Napin-Rich Canola Protein Isolate.

The objective was to study the safety of a Napin-Rich Canola Protein Isolate (NRCPI) fed to rats at various levels for 13-weeks. The study included four groups (20 animals/sex/group) of young Sprague Dawley rats. They were fed ad libitum with an AIN-93G based protein-free diet containing, respectively, 5%, 10% and 20% (w/w) NRCPI (test article) or 20% (w/w) vitamin-free casein (control article). Protein levels were adjusted at 18% in all groups with vitamin-free casein. Body weights, food consumption, locomotor activity and behavioral and clinical pathology parameters were recorded at various points in the study, followed by macroscopic examination, determination of organ weights and microscopic examination at termination. There were no test article-related effects on ophthalmology, functional observations, hematology, serum chemistry, urinalysis, organ weights and macroscopic or microscopic findings. Lower body weight gains were observed in the 10% NRCPI-treated males and the 20% NRCPI-treated males and females. The lower body weight gains were associated with significantly lower food consumption. Therefore, for NRCPI the No Observed Adversed Effect Level (NOAEL) was considered to be 20% (the highest fed level); equivalent to 12.46 g/kg BW/day for males and 14.95 g/kg BW/day for females. The NRCPI was considered safe under the tested conditions.

cmRNA/lipoplex encapsulation in PLGA microspheres enables transfection via calcium phosphate cement (CPC)/PLGA composites.

In this study lipoplexes containing chemically modified messenger RNA (cmRNA) were incorporated into poly (lactic-co-glycolic acid) (PLGA) microspheres via water-in-oil-in-water (W/O/W) double emulsion solvent evaporation technique. The nanoparticle encapsulation by microparticle formation was optimized to achieve lipoplex release and maximum transfection efficiency in surrounding cells. It was possible to adjust characteristic features in surface topology and size of the PLGA-microspheres by varying the extent of lipoplex loading into the polymer matrix. The partial release of lipids and mRNA out of the microparticle system, their accumulation in cells and the production of encoded protein were visualized via fluorescence microscopy. These bioactive microspheres, containing cmRNA bearing lipoplexes, were developed for the incorporation of a therapeutic component into injectable calcium phosphate cements (CPC). Due to the incorporation of PLGA/lipoplex microspheres as a degradable entity, the porosity of the cement phase could additionally be adjusted. This approach of complex nanoparticle incorporation into polymer/cement composites represents a promising example for combining transcript therapy with biomechanical engineering.

Glutamatergic and dopaminergic neurons mediate anxiogenic and anxiolytic effects of CRHR1.

The corticotropin-releasing hormone receptor 1 (CRHR1) critically controls behavioral adaptation to stress and is causally linked to emotional disorders. Using neurochemical and genetic tools, we determined that CRHR1 is expressed in forebrain glutamatergic and γ-aminobutyric acid-containing (GABAergic) neurons as well as in midbrain dopaminergic neurons. Via specific CRHR1 deletions in glutamatergic, GABAergic, dopaminergic, and serotonergic cells, we found that the lack of CRHR1 in forebrain glutamatergic circuits reduces anxiety and impairs neurotransmission in the amygdala and hippocampus. Selective deletion of CRHR1 in midbrain dopaminergic neurons increases anxiety-like behavior and reduces dopamine release in the prefrontal cortex. These results define a bidirectional model for the role of CRHR1 in anxiety and suggest that an imbalance between CRHR1-controlled anxiogenic glutamatergic and anxiolytic dopaminergic systems might lead to emotional disorders.

Chronic mild stress (CMS) in mice: of anhedonia, 'anomalous anxiolysis' and activity.

BACKGROUND: In a substantial proportion of depressed patients, stressful life events play a role in triggering the evolution of the illness. Exposure to stress has effects on different levels in laboratory animals as well and for the rat it has been shown that chronic mild stress (CMS) can cause antidepressant-reversible depressive-like effects. The adoption of the model to the mouse seems to be problematic, depending on the strain used and behavioural endpoint defined. Our aim was to evaluate the applicability of CMS to mice in order to induce behavioural alterations suggested to reflect depression-like symptoms. METHODOLOGY/PRINCIPAL FINDINGS: A weekly CMS protocol was applied to male mice of different mouse strains (D2Ola, BL/6J and BL/6N) and its impact on stress-sensitive behavioural measures (anhedonia-, anxiety- and depression-related parameters) and body weight was assessed. Overnight illumination as commonly used stressor in CMS protocols was particularly investigated in terms of its effect on general activity and subsequently derived saccharin intake. CMS application yielded strain-dependent behavioural and physiological responses including 'paradox' anxiolytic-like effects. Overnight illumination was found to be sufficient to mimic anhedonic-like behaviour in BL/6J mice when being applied as sole stressor. CONCLUSIONS/SIGNIFICANCE: The CMS procedure induced some behavioural changes that are compatible with the common expectations, i.e. 'anhedonic' behaviour, but in parallel behavioural alterations were observed which would be described as 'anomalous' (e.g. decreased anxiety). The results suggest that a shift in the pattern of circadian activity has a particular high impact on the anhedonic profile. Changes in activity in response to novelty seem to drive the 'anomalous' behavioural alterations as well.

A 13-week sub-chronic dietary toxicity study of a cruciferin-rich canola protein isolate in rats.

The objective was to evaluate the safety of a cruciferin-rich canola protein isolate (Puratein) when fed as a protein source at various dietary levels to rats for 13-weeks. The study included four groups (20 animals/sex/group) of young Sprague Dawley rats. They were fed ad libitum with an AIN-93 G based protein-free diet added respectively with 5%, 10% and 20% (w/w) Puratein (test article) or 20% (w/w) vitamin-free casein (control article). Protein levels were adjusted in all groups at 18% using vitamin-free casein. Body weights, food consumption, locomotor activity and behavioral and clinical pathology parameters were recorded at various points of the study, followed by macroscopic examination, determination of organ weights and microscopic tissue examination. There were no test article-related effects on body weight, food consumption, clinical observations, functional observational battery, motor activity, clinical pathology, or ophthalmic examinations. A slightly higher thyroid/parathyroid weight (g/100g BW) noted in the 20% Puratein group was not correlated with histopathological changes. The no-observed-effect-level (NOEL) was 10%, whereas the no-observed-adverse-effect-level (NOAEL) was the highest fed level of 20%, equivalent to 11.24 g/kg BW/day for males and 14.11 g/kg BW/day for females. The cruciferin-rich canola protein isolate (Puratein) was considered safe under the conditions tested.