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Introduction: The metabolic routes altered in Alzheimer's disease (AD) brain are poorly understood. As the metabolic pathways are evolutionarily conserved, the metabolic profiles carried out in animal models of AD could be directly translated into human studies.Methods: We performed untargeted Nuclear Magnetic Resonance metabolomics in hippocampus of McGill-R-Thy1-APP transgenic (Tg) rats, a model of AD-like cerebral amyloidosis and the translational potential of these findings was assessed by targeted Gas Chromatography-Electron Impact-Mass Spectrometry in plasma of participants in the German longitudinal cohort AgeCoDe.Results: In rat hippocampus 26 metabolites were identified. Of these 26 metabolites, nine showed differences between rat genotypes that were nominally significant. Two of them presented partial least square-discriminant analysis (PLS-DA) loadings with the larger absolute weights and the highest Variable Importance in Projection (VIP) scores and were specifically assigned to nicotinamide adenine dinucleotide (NAD) and nicotinamide (Nam). NAD levels were significantly decreased in Tg rat brains as compared to controls. In agreement with these results, plasma of AD patients showed significantly reduced levels of Nam in respect to cognitively normal participants. In addition, high plasma levels of Nam showed a 27% risk reduction of progressing to AD dementia within the following 2.5 years, this hazard ratio is lost afterwards.Discussion: To our knowledge, this is the first report showing that a decrease of Nam plasma levels is observed couple of years before conversion to AD, thereby suggesting its potential use as biomarker for AD progression.

Objectives Vein graft adaptation (VGA) is a process that vein as a vascular graft conduits in arterial reconstructive surgery; VGA can lead to postoperative vein graft stenosis (VGS) and complications after coronary artery bypass graft and other peripheral artery bypass surgeries. VGA is characterized by vein graft loss the venous features without exhibiting arterial features; furthermore, the activation of ERK inhibited the maintenance of venous properties of the vein graft. We hypothesized that ERK inhibition can affect vein VGS through regulating the expression of EphB4. Methods Rat vein transplantation model was established using wild-type and EphB4+/− Sprague-Dawley rats. Hematoxylin-eosin, Masson, Verhoeff, actin staining, and immunohistochemistry were applied to observe the structure of the vein grafts. Vascular smooth muscle cells (VSMCs) were isolated from the vein and vein grafts. Western blotting was used to determine the expression of p-ERK1/2 and EphB4, and immunofluorescence was applied to detect the expression and location of EphB4. Cell wound scratch assay and CCK8 assay were used to determine the migration and proliferation of VSMCs. Real-time polymerase chain reaction was used to determine the mRNA expression of EphB4. Results Western blotting in vein sample and vein graft sample detected p-ERK1/2 and ERK1/2 expression in both EphB4+/+ and EphB4+/− rats. The expression of p-ERK was increased in vein graft compared to vein. Immunofluorescence in VSMCs form EphB4+/+ and EphB4+/− rats detected EphB4 expression in both cells, and the expression of EphB4 was increased in VSMCs form EphB4+/+ rats. SCH772984 reduces the proliferation and migration of VSMCs. Inhibition of ERK suppressed the increase of vein graft wall thickness, and the expression of collagen fibers, elastic fibers, and α-actin was decreased. Vein graft from EphB4+/− rats reduces the expression of EphB4, and SCH772984 suppressed the decrease of EphB4 in vivo. Vein graft from EphB4+/− rats increased the expression of EphB4, and SCH772984 suppressed the increase of EphB4 in vivo. Conclusions The inhibition of ERK1/2 suppressed the process of VGS by decreasing the proliferation of VSMCs. The ERK-inhibitor SCH772984 suppressed the level of VGS by extending the time of EphB4 expression during the process of VGA, thus maintaining the venousization of vein graft. The mechanism may be that the inhibitor SCH772984 suppresses the level of VGS by extending the time of EphB4 expression during the process of VGA. Therefore, our research provides a new target of VGS treatment by inhibiting the expression of ERK1/2 through the process of VGA.

Cerebellar functions are modulated by cholinergic inputs, the density of which varies among cerebellar regions. Although the prepositus hypoglossi nucleus (PHN), a brainstem structure involved in controlling gaze holding, is known as one of the major sources of these cholinergic inputs, the proportions of cholinergic neurons in PHN projections to distinct cerebellar regions have not been quantitatively analyzed. In this study, we identified PHN neurons projecting to the cerebellum by applying retrograde labeling with dextran-conjugated Alexa 488 in choline acetyltransferase (ChAT)-tdTomato transgenic rats and compared the proportion of cholinergic PHN neurons in the PHN projections to four different regions of the cerebellum, namely the flocculus (FL), the uvula and nodulus (UN), lobules III-V in the vermis (VM), and the hemispheric paramedian lobule and crus 2 (PC). In the PHN, the percentage of cholinergic PHN neurons was lower in the projection to the FL than in the projection to the UN, VM or PC. Preposito-cerebellar neurons, except for preposito-FL neurons, included different proportions of cholinergic neurons at different rostrocaudal positions in the PHN. These results suggest that cholinergic PHN neurons project to not only the vestibulocerebellum but also the anterior vermis and posterior hemisphere and that the proportion of cholinergic neurons among projection neurons from the PHN differs depending on cerebellar target areas and the rostro-caudal regions of the PHN. This study provides insights regarding the involvement of cerebellar cholinergic networks in gaze holding.

HIV-related neurocognitive impairment can be worsened by cigarette smoking and be more severe in women. Therefore, we analyzed the effects of sex on behavioral function in HIV transgenic (Tg) rats that were exposed to either nicotine alone, to smoke from either nicotine-containing or nicotine-free cigarettes, or non-exposed. The animals were then assessed on the open field test for the total distance traveled and for the fraction of the total distance traveled and the total time spent in the center of the field, and the results then compared to WT rats subjected to the same exposures and testing. Higher total distances indicate greater locomotor activity and a higher center field measures imply a lower anxiety state. Total distances were overall higher for female and for Tg rats exposed to nicotine-free CS. Also, the total distance and both center field measures were overall higher for female rats in the control and nicotine-free CS-exposed groups. This was observed specifically for WT females as compared to WT males and, for the center field measures, for WT females as compared to Tg males. No genotype or sex-related differences were found for rats in the nicotine-free cigarette smoke (CS) and nicotine-containing CS exposed groups. Therefore, nicotine exposure did not impact genotype- and sex-related differences in motor responses and anxiety levels that were found in the control state. However, exposure to the non-nicotine components of CS resulted in locomotor activation in the presence of the HIV genes and was anxiogenic in WT and Tg male animals.

Chronic HIV infection causes redox stress and increases the risk of acute and chronic lung injury, even when individuals are adherent to antiretroviral therapy. HIV-1 transgene expression in rats inhibits nuclear factor (erythroid-derived 2)-like 2 (Nrf2), which regulates antioxidant defenses and alveolar epithelial cell (AEC) barrier function, but the mechanism is unknown. In this study, we present novel evidence that these pathological effects of HIV are mediated by microRNA-144 (miR-144). HIV-1 transgene expression in vivo increases the expression of miR-144 in the alveolar epithelium, and this can be replicated by direct exposure of naïve primary AECs to either Tat or gp120 ex vivo. Further, treating naïve primary AECs with a miR-144 mimic decreased the expression and activity of Nrf2 and inhibited their barrier formation. In contrast, treatment with a miR-144 antagomir increased the expression and activity of Nrf2 and improved barrier function in primary AECs isolated from HIV-1 transgenic rats. Importantly, either delivering the miR-144 antagomir intratracheally, or directly activating Nrf2 by dietary treatment with PB123, increased Nrf2 expression and barrier formation in HIV-1 transgenic rat AECs. This study provides new experimental evidence that HIV-induced inhibition of Nrf2 and consequent AEC barrier dysfunction are mediated via miR-144, and that these pathophysiological effects can be mitigated in vivo by either directly antagonizing miR-144 or activating Nrf2. Our findings suggest that targeting the inhibition of Nrf2 in individuals living with HIV could enhance their lung health and decrease the lung-specific morbidity and mortality that persists despite antiretroviral therapy.

Genetically altered rat and mouse models have been instrumental in the functional analysis of genes in a physiological context. In particular, studies on the renin-angiotensin system (RAS) have profited from this technology in the past. In this review, we summarize the existing animal models for the protective axis of the RAS consisting of angiotensin-converting enzyme 2 (ACE2), angiotensin-(1-7)(Ang-(1-7), and its receptor Mas. With the help of models with altered expression of the components of this axis in the brain and cardiovascular organs, its physiological and pathophysiological functions have been elucidated. Thus, novel opportunities for therapeutic interventions in cardiovascular diseases were revealed targeting ACE2 or Mas.

Stress urinary incontinence (SUI) is a significant health concern for patients affected, impacting their quality of life severely. To investigate mechanisms contributing to SUI different animal models were developed. Incontinence was induced under defined conditions to explore the pathomechanisms involved, spontaneous recovery, or efficacy of therapies over time. The animal models were coined to mimic known SUI risk factors such as childbirth or surgical injury. However, animal models neither reflect the human situation completely nor the multiple mechanisms that ultimately contribute to the pathogenesis of SUI. In the past, most SUI animal studies took advantage of rodents or rabbits. Recent models present for instance transgenic rats developing severe obesity, to investigate metabolic interrelations between the disorder and incontinence. Using recombinant gene technologies, such as transgenic, gene knock-out or CRISPR-Cas animals may narrow the gap between the model and the clinical situation of patients. However, to investigate surgical regimens or cell therapies to improve or even cure SUI, large animal models such as pig, goat, dog and others provide several advantages. Among them, standard surgical instruments can be employed for minimally invasive transurethral diagnoses and therapies. We, therefore, focus in this review on large animal models of SUI.

Post-traumatic Osteoarthritis (PTOA) is a degenerative joint disease, leading to articular cartilage breakdown, osteophyte formation, and synovitis, caused by an initial joint trauma. Pro-inflammatory cytokines increase catabolic activity and may perpetuate inflammation following joint trauma. Interleukin-15 (IL-15), a pro-inflammatory cytokine, is increased in OA patients, although its roles in OA pathophysiology are not well characterized.IL-15 levels appear to correlate to self-reported pain levels, and polymorphisms in the IL-15 receptor alpha gene correlate to a 1.5-fold increase in OA symptoms. This could be due to IL-15 effects on the activity of proteinases, such as matrix metalloproteinases (MMP) −1, −3, and −7. Here we utilized Il15 deficient rats to examine the role of IL-15 in PTOA pathogenesis in an injury-induced model of OA. OA was surgically induced in Il15 deficient rats and control wild-type rats to compare PTOA progression. Semi-quantitative scoring of the articular cartilage, subchondral bone, osteophyte size, and synovium was performed by two blinded observers. Analyses of articular cartilage damage, subchondral bone damage, and osteophyte formation revealed no significant difference between Il15 deficient rats and wild-type rats following PTOA-induction. Similarly, synovitis scoring across 6 parameters found no significant difference between genetic variants. Overall, IL-15 does not appear to play a key role in the development of structural changes in this surgically-induced rat model of PTOA.

Post-traumatic Osteoarthritis (PTOA) is a degenerative joint disease, leading to articular cartilage breakdown, osteophytes, and synovitis, caused by an initial joint trauma. Pro-inflammatory cytokines increase catabolic activity and may perpetuate inflammation following joint trauma. Interleukin-15 (IL-15), a pro-inflammatory cytokine, is increased in OA patients, although its exact role in the disease pathology is unknown. Using Il15 deficientrats, this study investigated the role of IL-15 in PTOA pathogenesis in an injury-induced model of OA. Semi-quantitative scoring of the articular cartilage, subchondral bone, and osteophyte formation reveals no significant difference between Il15 deficient rats and wild-type rats, following PTOA-induction. Similarly, synovitis scoring across 6 parameters found no significant difference between genetic variants. Overall, IL-15 does not appear to play a key role in PTOA pathogenesis in this model.

Background: Previously we showed that rats expressing the human angiotensinogen (AGT) gene (hAogen) exhibit sustained hypertension and cardiac dysfunction, associated with increased cardiac angiotensin II (Ang II). Recent evidence indicates that Ang II increases CaMKII activation which plays a crucial role in ANG II-related pathological processes associated with hypertension, hypertrophy and cardiac dysfunction. Although CaMKII inhibitors are being developed as safe and effective therapeutic agents, their mechanism of action remains to be fully understood. We tested the hypothesis that in hAogen rats, CaMKII is upregulated. Increased CaMKII activation may produce direct depression in LV myocyte basal function and β-adrenergic reserve. Acute inactivation of CaMKII with KN93 would have beneficial actions in hAogen. Methods: We compared LV myocyte CaMKIIδ expression and activity and myocyte functional performance in 10 Sprague Dawley (SD) control and 10 hAogen male rats. In hAogen, we further assessed myocyte contractile and [Ca 2+ ] i transient ([Ca 2+ ] iT ) responses to β-AR stimulation by isoproterenol (ISO, 10 -8 M) with and without pretreatment of myocytes with KN93 (10 -6 M, 30 min). Results: Versus SD, in hAogen myocytes, the CaMKIIδ protein levels (19%, 0.50 vs 0.42) and CaMKIIδ phosphorylation (at Thr 287 ) (35%, 0.27 vs 0.20) were significantly increased. These changes were followed by significantly reduced cell contraction (dL/dtmax, 104.9 vs 138.4 μm/s), relaxation (dR/dtmax, 93.0 vs 104.2 μm/s) and [Ca 2+ ] iT (0.15 vs 0.20). ISO-stimulated increases in dL/dtmax (43% vs 62%), dR/dtmax (32% vs 49%) and [Ca 2+ ] iT (19% vs 29%) were also significantly reduced. Moreover, in hAogen myocytes, pretreatment with KN93 markedly improved myocyte basal contraction (134.4 μm/s), relaxation (107.4 μm/s) and [Ca 2+ ] iT (0.20). ISO-induced increases in dL/dtmax (60%), dR/dtmax (50%), and [Ca 2+ ] iT (31%) were also significantly augmented. Conclusions: In rats harboring the human AGT gene, upregulation of CaMKIIδ has adverse functional effects. Acute endogenous CaMKII activation exacerbates LV myocyte dysfunction and β-AR desensitization. Inhibition of CaMKII has a significant beneficial impact in this established humanized model of hypertension.

Background: The transgenic rats expressing the human AGT gene [TGR (hAGT) L1623] (hAogen) is an established humanized model of hypertension. Recently we further found that this model is associated with declines in cardiac contractile function and β-adrenergic receptor (AR) reserve. However, the molecular basis is unclear. It has been suggested that pivotal restructuring of β-AR system is a critical determinant of the dysfunctional β-AR regulation in several cardiovascular diseases, including hypertension. But the alterations of subtypes of β-ARs have not been systemically evaluated in this model. Furthermore, there is significant crosstalk between β-AR signaling and CaMKII activation presenting CaMKII as a possible downstream mediator of detrimental β-AR signaling in the abnormal contractile phenotype of cardiac hypertrophy. However, the changes in cardiac CaMKII in this model are unknown. We tested the hypothesis that in hAogen, CaMKII and β 3 -AR are upregulated in the myocardium, but β 1 -AR is down-regulated, which are important causes of cardiac dysfunction and β-AR desensitization. Methods: We compared LV myocyte CaMKIIδ expression and activity and β 1 - and β 3 -AR expression and determined myocyte functional performance and [Ca 2+ ] i transient ([Ca 2+ ] iT) response to β -AR stimulation in myocytes obtained from 6 Sprague Dawley (SD) control and 6 haogen male adult rats. Results: Compared with SD, in hAogen LV myocytes, β 3 -AR protein level significantly increased (26%, 0.29 vs 0.23), but β 1 -AR protein level (26%, 0.4 vs 0.54) significantly decreased. The CaMKIIδ protein levels (16%, 0.50 vs 0.43) and CaMKIIδ phosphorylation (at Thr287) (35%, 0.27 vs 0.20) were significantly increased. These changes were followed by significantly reduced cell contraction (dL/dt max , 102.1vs 138.8μm/s), relaxation (dR/dt max , 94.0 vs 104.7 μm/s) and [Ca 2+ ] iT (0.15 vs 0.21). ISO-stimulated increases in dL/dt max (42% vs 60%), dR/dt max (36% vs 51%) and [Ca 2+ ] iT (20% vs 31%) were also significantly reduced. Conclusions: The upregulation of LV myocyte CaMKIIδ and contrast changes in β 3 -AR and β 1 -AR may be the important cause of the abnormal contractile phenotype and β-AR desensitization in this humanized angiotensinogen model of hypertension of TGR (hAGT) L1623.

Background: Transgenic rats expressing the human angiotensinogen gene [TGR (hAogen) 1623] (hAogen) exhibit sustained hypertension and systolic dysfunction associated with altered cardiac renin-angiotensin system and β- adrenergic receptor (AR) signal transduction systems. We have shown previously, in contrast to β 1 - and β 2 -ARs, β 3 -ARs are linked to G i proteins, and stimulation of β 3 -ARs inhibits cardiac contraction and relaxation. Hypertension is associated with increased cardiac expression of G i proteins. This may alter β 3 -AR stimulation and play an important role in the cardiac functional impairment of this humanized model of hypertension. However, the alteration and functional effect of β 3 -AR activation in this model are unknown. We tested the hypothesis that high cardiac tissue Ang II content in hAogen may cause an up-regulation of cardiac β 3 -AR, which exacerbates myocyte dysfunction and impairs calcium regulation, thereby directly contributing to the cardiac dysfunction. Methods: We compared LV myocyte β 3 -AR expression and myocyte functional and [Ca 2+ ] i transient ([Ca 2+ ] iT ) responses to β- and β 3 -AR stimulation in myocytes obtained from 8 Sprague Dawley (SD) control and 8 hAogen male adult rats. Results: Versus SD, in hAGT rats, basal myocyte contraction (dL/dt max , 107.1 vs 138.8 μm/s), relaxation (dR/dt max , 94.0 vs 103.9 μm/s) and [Ca 2+ ] iT (0.15 vs 0.21) were depressed. A non-selective β-AR agonist, isoproterenol (ISO) (10 -8 M) produced significantly smaller increases in dL/dt max , (42% vs. 61%), dR / dtmax (35% vs. 51%), and [Ca 2+ ] iT (20% vs. 30%). Moreover, versus SD, in hAogen rats, LV myocyte β 3 -AR protein level increased by 32% (0.29 vs 0.22) with resulted significantly altered myocyte functional response to β 3 -AR stimulation. Compared with the changes in SD myocytes, in hAogen myocytes, BRL (10 -8 M) produced a significantly greater decreases in dL/dt max , (27% vs 12%), dR/dt max (28% vs 11%), and [Ca 2+ ] iT (17% vs 10%). Conclusions: TGR (hAogen) 1623, this humanized model of hypertension is associated with an up-regulation of LV myocyte β 3 -AR, which enhances β 3 -AR-caused inhibition of myocyte contractile, relaxation and [Ca 2+ ] iT and exacerbates β-AR desensitization, thereby directly contributing to the cardiac dysfunction.

Physical performance and systolic blood pressure (SBP) during aging in normotensive female Sprague-Dawley (SD) and hypertensive (mRen2)27 transgenic rats were assessed following long-term treatment with a Muscadine Grape Extract (MGE, Piedmont Research and Development Corp). MGE was administered at a dose of 0.2 mg/mL in the drinking water starting at 14 weeks (wks) of age with an endpoint at 70 wks of age (total time of treatment of 56 wks). At 20-, 40- and 70-wks of age, physical performance (exercise capacity in seconds and workload in grams - meters) was determined using a treadmill at a velocity of 17 cm/second with a 5% incline. SBP was determined by tail-cuff plethysmography in trained rats. There were no significant differences in physical performance between SD and (mRen2)27 female rats at any age despite the higher SBP in the (mRen2)27 rats at all ages. Long-term treatment with MGE had no significant effect on physical performance or SBP in SD rats at any age. In contrast, MGE treatment markedly increased exercise capacity (40 wks: 1615 ± 166 vs 4943 ± 442 seconds, p

International audience; Cocaine addiction is a chronic and relapsing disorder with an important genetic component. Human candidate gene association studies showed that the single nucleotide polymorphism (SNP) rs16969968 in the α5 subunit (α5SNP) of nicotinic acetylcholine receptors (nAChRs), previously associated with increased tobacco dependence, was linked to a lower prevalence of cocaine use disorder (CUD). Three additional SNPs in the α5 subunit, previously shown to modify α5 mRNA levels, were also associated with CUD, suggesting an important role of the subunit in this pathology. To investigate the link between this subunit and CUD, we submitted rats knockout for the α5 subunit gene (α5KO), or carrying the α5SNP, to cocaine self-administration (SA) and showed that the acquisition of cocaine-SA was impaired in α5SNP rats while α5KO rats exhibited enhanced cocaine-induced relapse associated with altered neuronal activity in the nucleus accumbens. In addition, we observed in a human cohort of patients with CUD that the α5SNP was associated with a slower transition from first cocaine use to CUD. We also identified a novel SNP in the β4 nAChR subunit, part of the same gene cluster in the human genome and potentially altering CHRNA5 expression, associated with shorter time to relapse to cocaine use in patients. In conclusion, the α5SNP is protective against CUD by influencing early stages of cocaine exposure while CHRNA5 expression levels may represent a biomarker for the risk to relapse to cocaine use. Drugs modulating α5 containing nAChR activity may thus represent a novel therapeutic strategy against CUD.

Background: Leucine-rich repeat kinase 2 (LRRK2) mutations are the most common genetic risk factor for Parkinson's disease (PD). While the corresponding pathogenic mechanisms remain largely unknown, LRRK2 has been implicated in the immune system.Objective: To assess whether LRRK2 mutations alter the sensitivity to a single peripheral inflammatory trigger, with ultimate impact on dopaminergic integrity, using a longitudinal imaging-based study design.Methods: Rats carrying LRRK2 p.G2019S and non-transgenic (NT) littermates were treated peripherally with lipopolysaccharide (LPS). They were monitored over 10 months with PET markers for neuroinflammation and dopaminergic integrity, and with behavioral testing. Tyrosine hydroxylase and CD68 expression were assessed postmortem, 12 months after LPS treatment, in the striatum and substantia nigra.Results: Longitudinal [C-11]PBR28 PET imaging revealed that LPS treatment caused inflammation in the brain, increasing over time, as compared to saline (corrected p = 0.008). LPS treated LRRK2 animals exhibited significantly increased neuroinflammation in the cortex and ventral-regions compared to saline treated animals (LRRK2 and NT) at 10 months post treatment, with the increase in [C-11] PBR28 binding from baseline averaging 0.128 +/- 0.045 g/mL. For LPS treated NT animals, the increase was not significant. CD68 immunohistochemistry data supported the imaging results, but without reaching statistical significance. No dopaminergic degeneration was observed.Conclusion: A single peripheral inflammatory trigger elicited long lasting, progressive neuroinflammation. A trend for an exacerbated inflammatory response in LRRK2 animals compared to NT controls was observed. Translationally, this implies that repeated exposure to inflammatory triggers may be needed for LRRK2 mutation carriers to develop active PD.

Background Cerebral amyloid angiopathy (CAA) is a common cerebral small vessel disease of the aged and a prominent comorbidity of Alzheimer’s disease (AD). CAA can promote a variety of vascular-related pathologies including neuroinflammation, cerebral infarction, and hemorrhages, which can all contribute to vascular cognitive impairment and dementia (VCID). Our understanding of the pathogenesis of CAA remains limited and further investigation of this condition requires better preclinical animal models that more accurately reflect the human disease. Recently, we generated a novel transgenic rat model for CAA (rTg-DI) that develops robust and progressive microvascular CAA, consistent microhemorrhages and behavioral deficits. Methods In the current study, we investigated perivascular pathological processes that accompany the onset and progressive accumulation of microvascular CAA in this model. Cohorts of rTg-DI rats were aged to 3 months with the onset of CAA and to 12 months with advanced stage disease and then quantitatively analyzed for progression of CAA, perivascular glial activation, inflammatory markers, and perivascular stress. Results The rTg-DI rats developed early-onset and robust accumulation of microvascular amyloid. As the disease progressed, rTg-DI rats exhibited increased numbers of astrocytes and activated microglia which were accompanied by expression of a distinct subset of inflammatory markers, perivascular pericyte degeneration, astrocytic caspase 3 activation, and disruption of neuronal axonal integrity. Conclusions Taken together, these results demonstrate that rTg-DI rats faithfully mimic numerous aspects of human microvascular CAA and provide new experimental insight into the pathogenesis of neuroinflammation and perivascular stress associated with the onset and progression of this condition, suggesting new potential therapeutic targets for this condition. The rTg-DI rats provide an improved preclinical platform for developing new biomarkers and testing therapeutic strategies for microvascular CAA.

BACKGROUND: Improvement of bladder emptying by modulating afferent nerve activity is an attractive therapeutic strategy for detrusor underactivity. Transient receptor potential vanilloid 4 (TRPV4) is a sensory ion channel in urothelial cells that contribute to the detection of bladder filling. OBJECTIVE: To investigate the potential benefit of intravesical TRPV4 agonists in a pelvic nerve injury rat model for detrusor underactivity. DESIGN, SETTING, AND PARTICIPANTS: Female wild-type and Trpv4 knockout rats underwent sham surgery or bilateral pelvic nerve injury (bPNI). Four weeks later, rats underwent cystometry with infusion of the TRPV4 agonist GSK1016790A. Bladders were harvested for in vitro pharmacological studies, quantitative reverse polymerase chain reaction and immunohistochemistry. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Data are expressed as median ± interquartile range. Statistical comparisons were made using the Mann-Witney U test and Wilcoxon signed rank test as appropriate. RESULTS AND LIMITATIONS: Rats with bPNI showed a phenotype characteristic of detrusor underactivity with lower-amplitude voiding contractions, decreased voiding frequency, and increased postvoid residual. Intravesical application of GSK1016790A increased voiding frequency and reduced postvoid residual in wild-type, but not Trpv4-/-, rats. In isolated bladder strips, GSK1016790A did not induce relevant contractions, indicating that the observed improvements in bladder function are the result of increased afferent signalling through TRPV4 activation, rather than a local effect on the detrusor. The altered urinary phenotype of Trpv4-/- mice was not apparent in the Trpv4-/- rat model, suggesting species-related functional variations. Our results are limited to the preclinical setting in rodents. CONCLUSIONS: Intravesical activation of TRPV4 improves bladder dysfunction after bPNI by increasing afferent signalling. PATIENT SUMMARY: We demonstrate that the sensory protein transient receptor potential vanilloid 4 (TRPV4) can be targeted to improve bladder function in animals that have iatrogenic injury to the nerves innervating the bladder. Further research is required to determine whether these results can be translated to patients with an underactive bladder. ispartof: EUROPEAN UROLOGY vol:74 issue:3 pages:336-345 ispartof: location:Switzerland status: published

Spondyloarthritides (SpA) include inflammatory joint diseases with various clinical phenotypes that may also include the axial skeleton and/or entheses. SpA include psoriatic arthritis, reactive arthritis, enteropathic arthritis and ankylosing spondylitis; the latter is frequently associated with extra-articular manifestations, such as uveitis, psoriasis, and inflammatory bowel disease. SpA are associated with the HLA-B27 allele and recognize T cells as key pathogenetic players. In contrast to other rheumatic diseases, SpA affect women and men equally and are not associated with detectable serum autoantibodies. In addition, but opposite to rheumatoid arthritis, SpA are responsive to treatment regimens including IL-23 or IL-17-targeting biologics, yet are virtually unresponsive to steroid treatment. Based on these differences with prototypical autoimmune diseases, such as rheumatoid arthritis or connective tissue diseases, SpA may be better classified among autoinflammatory diseases, with a predominant innate immunity involvement. This would rank SpA closer to gouty arthritis and periodic fevers in the spectrum of rheumatic diseases, as opposed to autoimmune-predominant diseases. We herein provide available literature on risk factors associated with SpA in support of this hypothesis with a specific focus on genetic and environmental factors.

Spondyloarthritides (SpA) include inflammatory joint diseases with various clinical phenotypes that may also include the axial skeleton and/or entheses. SpA include psoriatic arthritis, reactive arthritis, enteropathic arthritis and ankylosing spondylitis; the latter is frequently associated with extra-articular manifestations, such as uveitis, psoriasis, and inflammatory bowel disease. SpA are associated with the HLA-B27 allele and recognize T cells as key pathogenetic players. In contrast to other rheumatic diseases, SpA affect women and men equally and are not associated with detectable serum autoantibodies. In addition, but opposite to rheumatoid arthritis, SpA are responsive to treatment regimens including IL-23 or IL-17-targeting biologics, yet are virtually unresponsive to steroid treatment. Based on these differences with prototypical autoimmune diseases, such as rheumatoid arthritis or connective tissue diseases, SpA may be better classified among autoinflammatory diseases, with a predominant innate immunity involvement. This would rank SpA closer to gouty arthritis and periodic fevers in the spectrum of rheumatic diseases, as opposed to autoimmune-predominant diseases. We herein provide available literature on risk factors associated with SpA in support of this hypothesis with a specific focus on genetic and environmental factors.

The parafacial respiratory group (pFRG) surrounding the ventrolateral part of the facial motor nucleus is one of respiratory rhythm generators that consists of pre-inspiratory (Pre-I) neurons. Previous studies showed that most of the Pre-I neurons locating in the Phox2b cluster of the rostral ventral medulla were also Phox2b positive and intrinsically CO2 sensitive. However, it is not clear what percentage of Phox2b-expressing cells in the pFRG of the ventral medulla are Pre-I neurons. To address this issue, we analyzed the activity of Phox2b-positive cells by calcium imaging using a confocal laser microscope in transgenic rats in which Phox2b-positive cells expressed EYFP. We found that more than 60% of the EYFP/Phox2b-positive cells showed Pre-I neuron-like rhythmic burst activity in the parafacial region of newborn rat.

Neurotransmitters (NT) are widely distributed in the central nervous system. These molecules are important for many physiological processes and the function of the immune system. Imbalance of NT are linked to numerous neurological disorders and diseases, including tauopathies. Here, a targeted approach based on on-line combination of ultra-high performance liquid chromatography with tandem mass spectrometry was validated and applied to the quantitative analysis of nine NT (acetylcholine, choline, aspartic acid, asparagine, glutamic acid, glutamine, pyroglutamate, γ-aminobutyric acid, N-acetyl-L-aspartic acid), tryptophan and its metabolite kynurenine in brain tissue samples of a rat model for tauopathy. The applied analytical method was characterized by excellent validation parameters for all analytes, such as limits of detection in the range of 0.01–1.70 µg/mL, regression coefficients of the calibration curves ≥ 0.9946, intra-day and inter-day precision expressed as coefficient of variation in the range of 0.6–11.9% and 0.6–14.4%, and accuracy in the range of 87.6–107.1% and 87.2–119.6%. Our analytical approach led to the identification of increased levels of choline and γ-aminobutyric acid in pons, and elevated concentration levels of pyroglutamate in medulla oblongata. These findings indicate that NT could play a valuable role in the study and clarification of neuroinflammation and neurodegenerative diseases.

Background Mutant transactive response DNA-binding protein (TDP-43) is closely correlated to the inherited form of amyotrophic lateral sclerosis (ALS). TDP-43 transgenic rats can reproduce the core phenotype of ALS and constitutive expression of TDP-43 caused postnatal death. Objective The study aimed to understand whether neurologic deficiency caused by mutant TDP- 43 is dependent on its temporal expression. Method Transgenic rats were established that express mutant human TDP-43 (M337V substitution) in neurons, then a Tet-off system was used to regulate its expression. Results TDP-43 mutant transgenic rats developed significant weakness after the transgene was activated. Rats with expression of mutant TDP-43 at 30 days showed a more aggressive phenotype. More severe pathological changes in neurogenic atrophy were observed in these rats. Conclusion Temporal expression of mutant TDP-43 in neurons promoted serious phenotype in rats. The dysfunction of TDP-43 had a profound impact on the development of motor neurons and skeletal muscles.

Glioma is a unique neoplastic disease that develops exclusively in the central nervous system (CNS) and rarely metastasizes to other tissues. This feature strongly implicates the tumor-host CNS microenvironment in gliomagenesis and tumor progression. We investigated the differences and similarities in glioma biology as conveyed by transcriptomic patterns across four mammalian hosts: rats, mice, dogs, and humans. Given the inherent intra-tumoral molecular heterogeneity of human glioma, we focused this study on tumors with upregulation of the platelet-derived growth factor signaling axis, a common and early alteration in human gliomagenesis. The results reveal core neoplastic alterations in mammalian glioma, as well as unique contributions of the tumor host to neoplastic processes. Notable differences were observed in gene expression patterns as well as related biological pathways and cell populations known to mediate key elements of glioma biology, including angiogenesis, immune evasion, and brain invasion. These data provide new insights regarding mammalian models of human glioma, and how these insights and models relate to our current understanding of the human disease. NIH [T32 CA154274, F30-CA200345-01, R01CA139099, K12 NS080223, K08 NS090430]; Wallace Coulter Foundation; Passano Foundation; American Cancer Society-Research Scholar Grant [128970-RSG-16-012-01-CDD] This study was supported by NIH T32 CA154274 (NC), NIH F30-CA200345-01 (MBS), NIH R01CA139099 (JHR); the Wallace Coulter Foundation (JHR); the Passano Foundation (GW); NIH K12 NS080223 Neurosurgeon Research Career Development Program (GW), NIH K08 NS090430 (GW), American Cancer Society-Research Scholar Grant 128970-RSG-16-012-01-CDD (GW).

Single moderate-to-severe traumatic brain injuries (TBIs) may increase subsequent risk for neurodegenerative disease by facilitating β-amyloid (Aβ) deposition. However, the chronic effects on Aβ pathogenesis of repetitive mild TBIs (rTBI), which are common in adolescents and young adults, remain uncertain. We examined the effects of rTBI sustained during adolescence on subsequent deposition of Aβ pathology in a transgenic APP/PS1 rat model. Transgenic rats received sham or four individual mild TBIs (rTBIs) separated by either 24- or 72-h intervals at post-natal day 35 (before Aβ plaque deposition). Animals were euthanized at 12 months of age and underwent immunohistochemical analyses of Aβ plaque deposition. Significantly greater hippocampal Aβ plaque deposition was observed after rTBI separated by 24 h relative to rTBI separated by 72 h or sham injuries. These increases in hippocampal Aβ plaque load were driven by increases in both plaque number and size. Similar, though less-pronounced, effects were observed in extrahippocampal regions. Increases in Aβ plaque deposition were observed both ipsilaterally and contralaterally to the injury site and in both males and females. rTBIs sustained in adolescence can increase subsequent deposition of Aβ pathology, and these effects are critically dependent on interinjury interval.

Angiotensin-(1-7) counterbalances angiotensin II cardiovascular effects. However, it has yet to be determined how cardiovascular autonomic modulation may be affected by chronic and acute elevation of Ang-(1-7). Hemodynamics and cardiovascular autonomic profile were evaluated in male Sprague-Dawley (SD) rats and transgenic rats (TGR) overexpressing Ang-(1-7) [TGR(A1-7)3292]. Blood pressure (BP) was directly measured while cardiovascular autonomic modulation was evaluated by spectral analysis. TGR received A-779 or vehicle and SD rats received Ang-(1-7) or vehicle and were monitored for 5 h after i.v. administration. In another set of experiments with TGR, A-779 was infused for 7 days using osmotic mini pumps. Although at baseline no differences were observed, acute administration of A-779 in TGR produced a marked long-lasting increase in BP accompanied by increased BP variability (BPV) and sympathetic modulation to the vessels. Likewise, chronic administration of A-779 with osmotic mini pumps in TGR increased heart rate, sympathovagal balance, BPV, and sympathetic modulation to the vessels. Administration of Ang-(1-7) to SD rats increased heart rate variability values in 88% accompanied by 8% of vagal modulation increase and 18% of mean BP reduction. These results show that both acute and chronic alteration in the Ang-(1-7)-Mas receptor axis may lead to important changes in the autonomic control of circulation, impacting either sympathetic and (or) parasympathetic systems.

Current advancements in neurovascular biology relates a mechanoceutics treatment, known as cranial osteopathic manipulation (COM), Alzheimer's disease (AD). COM could be used as an evidence-based treatment strategy to improve the symptoms of AD if molecular mechanisms, which currently remain unclear, are elucidated. In the present pilot study, using transgenic rats, we have identified COM mediated changes in behavioral and biochemical parameters associated with AD phenotypes. We expect these changes may have functional implications that might account for improved clinical outcomes of COM treatment. Further investigations on COM will be helpful to establish an adjunct treatment for AD.

Angiotensin-(1-12) [Ang-(1-12)], an alternate substrate for tissue angiotensin II (Ang II) formation, underscores the importance of alternative renin-independent pathway(s) for the generation of angiotensins. Since renin enzymatic activity is species-specific, a transgenic model of hypertension due to insertion of the human angiotensinogen (AGT) gene in Sprague Dawley rats allowed for characterizing the contribution of a non-renin dependent mechanism for Ang II actions in their blood and heart tissue. With this in mind, we investigated whether TGR(hAGT)L1623 transgenic rats express the human sequence of Ang-(1-12) before and following a 2-week oral therapy with the type I Ang II receptor (AT1-R) antagonist valsartan. Plasma and cardiac expression of angiotensins, plasma renin activity, cardiac angiotensinogen, and chymase protein and the enzymatic activities of chymase, angiotensin converting enzyme (ACE) and ACE2 were determined in TGR(hAGT)L1623 rats given vehicle or valsartan. The antihypertensive effect of valsartan after 14-day treatment was associated with reduced left ventricular wall thickness and augmented plasma concentrations of angiotensin I (Ang I) and Ang II; rat and human concentrations of angiotensinogen or Ang-(1-12) did not change. On the other hand, AT1-R blockade produced a 55% rise in left ventricular content of human Ang-(1-12) concentration and no changes in rat cardiac Ang-(1-12) levels. Mass-Spectroscopy analysis of left ventricular Ang II content confirmed a >4-fold increase in cardiac Ang II content in transgenic rats given vehicle; a tendency for decreased cardiac Ang II content following valsartan treatment did not achieve statistical significance. Cardiac chymase and ACE2 activities, significantly higher than ACE activity in TGR(hAGT)L1623 rats, were not altered by blockade of AT1-R. We conclude that this humanized model of angiotensinogen-dependent hypertension expresses the human sequence of Ang-(1-12) in plasma and cardiac tissue and responds to blockade of AT1-R with further increases in the human form of cardiac Ang-(1-12). Since rat renin has no hydrolytic activity on human angiotensinogen, the study confirms and expands knowledge of the importance of renin-independent mechanisms as a source for Ang II pathological actions.

Angiotensin-(1-7) (Ang-[1-7]) can modulate glucose metabolism and protect against muscular damage. The aim of this study was to investigate the influence of lifetime increase of circulating levels of Ang-(1-7) at exhaustive swimming exercise (ESE). Sprague-Dawley (SD) and transgenic rats TGR(A1-7)3292 (TR) which overproduce Ang-(1-7) (2.5-fold increase) were submitted to ESE. The data showed no differences in time to exhaustion (SD: 4.90 ± 1.37 h vs. TR: 5.15 ± 1.15 h), creatine kinase, and transforming growth factor beta (TGF-β). Lactate dehydrogenase (SD: 219.9 ± 12.04 U/L vs. TR: 143.9 ± 35.21 U/L) and α-actinin (SD: 336.7 ± 104.5 U/L vs. TR: 224.6 ± 82.45 U/L) values were significantly lower in TR. There was a significant decrease in the range of blood glucose levels (SD: −41.4 ± 28.32 mg/dl vs. TR: −13.08 ± 39.63 mg/dl) in SD rats. Muscle (SD: 0.06 ± 0.02 mg/g vs. TR: 0.13 ± 0.01 mg/g) and hepatic glycogen (SD: 0.66 ± 0.36 mg/g vs. TG: 2.24 ± 1.85 mg/g) in TR were higher. The TR presented attenuation of the increase in skeletal muscle damage biomarkers and of the changes in glucose metabolism after ESE.

The use of fixed fibroblasts from familial and sporadic Alzheimer's disease patients has previously indicated an upregulation of mitochondria-ER contacts (MERCs) as a hallmark of Alzheimer's disease. Despite its potential significance, the relevance of these results is limited because they were not extended to live neurons. Here we performed a dynamic in vivo analysis of MERCs in hippocampal neurons from McGill-R-Thy1-APP transgenic rats, a model of Alzheimer's disease-like amyloid pathology. Live FRET imaging of neurons from transgenic rats revealed perturbed 'lipid-MERCs' (gap width

The HIV-1 transgenic (Tg) rat model is valuable for understanding HIV-associated neurocognitive disorders (HAND) and accompanying substance use and misuse. Tg and F344/NHsd wildtype (WT) rats were allowed to self-administer intrajugular cocaine. For the first seven sessions, neither genotype self-administered cocaine (0.1 mg/kg/infusion) on a fixed ratio 1 schedule. We thus implemented a lever–cocaine “autoshaping” session followed by a series of manipulations changing dose and reinforcement schedule. Tg rats self-administered much less cocaine than WT rats throughout the study. Five of eight Tg rats modestly increased self-administration from sessions 36–50. Of those, only three showed a lever discrimination. Eight of ten WT rats acquired robust self-administration by session 19; all WT rats self-administered cocaine by the end of the study. WT and Tg rats had similar baseline locomotor activity in the self-administration chamber suggesting that the low levels of cocaine intake in the Tg rats did not reflect a non-specific motor impairment in this rat strain. Concomitant measurement of activity with self-administration revealed activity increases that followed increased cocaine intake. That relation held in Tg rats. Therefore, the present study provides evidence that HIV-1 Tg rats are less sensitive to the reinforcing effects of cocaine than their F344 WT counterparts.

Dark-rearing has been found to slow the rate of retinal degeneration in albino P23H but not S334ter mutant rhodopsin transgenic (Tg) rats. Since eye pigmentation has the same protective slowing effect as dark-rearing in RCS rats, we examined whether eye pigmentation has a comparable slowing effect in the different mutant rhodopsin Tg rats. Different lines of albino P23H and S334ter Tg rats on the Sprague-Dawley (SD) background were bred to Long-Evans (LE) rats to produce pigmented Tg rats. These were compared to albino Tg rats at postnatal days of different ages using the outer nuclear layer (ONL) as a morphological measure of photoreceptor number and electroretinogram (ERG) a- and b-wave amplitudes as a measure of retinal function. When compared to albino P23H rats, pigmented P23H rats had a slower rate of degeneration as measured by greater ONL thicknesses and greater ERG a- and b-wave amplitudes. By contrast, pigmented S334ter rats showed no difference in ONL thicknesses or ERG a- and b-wave amplitudes when compared to their albino equivalents. Thus, degeneration of photoreceptors in P23H Tg rats is slowed by eye pigmentation as measured by ONL thickness, while it is not in the S334ter Tg rats. Eye pigmentation also protects functional changes in ERG a- and b-waves for the P23H lines, but not for the S334ter lines.

Background: Hyperlipidemia and inflammation are critical components in the pathophysiology of endothelial disorder, which can lead to vascular complications. Our study aimed to evaluate the effects of immunomodulatory therapy (methotrexate and infliximab) in a diet-induced hyperlipidemia rat model. Methods: Sprague-Dawley (wild type (WT), male, n = 32) rats&nbsp, were divided into four groups: one group fed with standard diet (SD), one group fed with high lipid diet (HLD), and two groups that received HLD and drug treatment (methotrexate (Mtx) or infliximab (Ifx)). In order to evaluate if modifications to the endothelial cells may influence the risk of vascular complications following hyperlipidemia or treatment reactivity, each group was doubled by a rats group that overexpressed beta-3 receptors on the endothelial cells (transgenic (TG-beta 3), male, n = 32). Serum lipid profile, liver enzymes, oxidative stress, and inflammation markers were determined. Histopathologic analysis of the liver and aorta was performed. Results: After 9 weeks of HLD, rats exhibited significant pathologic serum lipid profiles, elevated oxidative stress, and pro-inflammatory markers. Additionally, the aortic histopathological analysis revealed aorta media-intima thickening (p &lt, 0.05) in the transgenic group. Methotrexate and infliximab significantly decreased inflammation and oxidative stress parameters, but presented opposing effects on lipid profiles (methotrexate decreased, whereas infliximab increased the atherosclerosis index). Drug treatment decreased the aorta media-intima thickness (p &lt, 0.05) only in transgenic rats. Conclusions: HLD was associated with hyperlipidemia, inflammation and oxidative stress. The overexpression of beta-3 receptors on endothelial cells increased aortic thickening in response to the HLD. Methotrexate and infliximab reduced oxidative stress and inflammation in all groups, but led to favorable histopathologic vascular results only in the transgenic groups.

Mammary cancer is the most common type of cancer and the fifth most common cause of cancer-related deaths among Japanese women. The recent sharp increase in the number of women diagnosed with mammary cancer per year is thought to be associated with increased fat intake resulting from changes in the dietary habits of contemporary Japanese citizens. In this study, human c-Ha-ras proto-oncogene transgenic (Hras128) rats, which are highly susceptible to mammary carcinogens, were fed high- or low-fat diets to examine the relationship between fat consumption and the development of mammary cancer. Female 7-week-old Hras128 rats and wild-type littermates were administered benzo[a]pyrene. A week later, the animals were randomly assigned to high-fat or low-fat diet groups (45% or 10% of calories from fat, respectively). After 12 weeks, the rats were sacrificed and autopsied, and mammary tumors were excised and processed for microscopic observation. Mammary tumors were found in 11 of the 12 animals in the high-fat diet group and in 5 of the 12 animals in the low-fat diet group, and the numbers of mammary gland tumors per animal in these groups were 1.7 and 0.7, respectively. Notably, the observed differences in incidence and multiplicity of mammary tumors between the two groups were statistically significant. These results suggest a positive relationship between the incidence of breast cancer and high fat intake.

下垂体後葉ホルモンの一つであるオキシトシン（oxytocin: OXT）は，視床下部室傍核（paraventricular nucleus: PVN）および視索上核（supraoptic nucleus: SON）の大細胞性神経分泌ニューロンの細胞体で産生され，下垂体後葉（posterior pituitary: PP）に投射した軸索終末より血中に分泌される．OXTの生理的役割として子宮収縮，乳汁分泌が古典的に知られてきたが，近年では社会性や信頼関係にも関与していることが明らかになってきた．また，鎮痛，抗炎症，ストレス緩和ならびに摂食抑制作用なども有することが示唆されている．なお，OXT受容体は侵害受容情報の伝達に重要な脊髄後角にも存在することが報告されている．PVNの大細胞性領域の神経分泌ニューロンで産生されたOXTはPPより血中に分泌される．一方，PVNの小細胞性領域のOXTニューロンは延髄および脊髄にもその軸索を投射しており，自律神経系や疼痛調整に関与していると考えられているが，詳細な機序については不明なところが多い．本稿では，これまでの臨床研究ならびにOXT-単量体赤色蛍光タンパク1（monomeric red fluorescent protein 1: mRFP1）トランスジェニックラットを用い，急性ならびに慢性疼痛・炎症モデルラットの視床下部神経核・PP・脊髄におけるOXT-mRFP1融合遺伝子の発現動態を可視化・定量化した自験例（動物研究）を中心に，OXTと疼痛ならびに炎症調節作用との関連について解説する．Oxytocin (OXT), which is a well-known neurohypophysial hormone that is synthesized in the paraventricular (PVN) and supraoptic nuclei (SON) of the hypothalamus, is secreted from the posterior pituitary (PP) into the systemic circulation, where it plays an essential role in reproduction, especially during and after childbirth. Many recent studies have shown that OXT contributes to the modulation of several functions, such as social recognition, trust building, anti-nociception, anti-inflammation, stress relief and suppression of feeding. However, little is known about the neuronal networks responsible for OXT effects. Endogenious OXT has two regulations: the 1st regulation is humoral regulation, in which OXT is delivered to target organs from PP via the bloodstream; the 2nd regulation is nerve regulations, in which OXT from parvocellular neurosecretory neurons in the PVN directly project to the central nerve system (CNS). OXT binding sites, as well as OXT receptor expression, are located in various regions of the CNS, including the dorsal horn of spinal cord in rats, where it plays an important role in nociception. We examined the response to acute and chronic nociception/-inflammation in rat models using OXT-monomeric red fluorescent protein 1 (mRFP1) transgenic rats. We used formalin test as acute nociceptive/-inflammatory rat models and adjuvant arthritis as chronic nociceptive/-inflammatory rat models. We studied the effects of acute and chronic nociception/-inflammation on OXT-mRFP1 expression in the hypothalamus, posterior pituitary and spinal cord, and examined the role that OXT plays in acute and chronic nociceptive responses in rats. This review focuses on pain modulation and anti-inflammation by OXT according to previous clinical and animal research.

Graphical abstract Trace (A) shows a typical transient [Ca2+]i response induced by 50 mM K+ observed in an AVP-eGFP neurone (inset), Trace (B) shows the spontaneous [Ca2+]i oscillations observed in an AVP-eGFP neurone (inset). The corresponding changes in the fluorescence are shown in C and D, respectively., Highlights • Supraoptic fluorescent vasopressin (AVP-eGFP) and oxytocin (OT-mRFP1) neurones exhibit distinct spontaneous [Ca2+]i oscillations. • Vasopressin triggers [Ca2+]i oscillations, intensifies existing oscillations, and exceptionally stops oscillations. • Hyper- or hypo-osmotic stimuli have an intensifying or inhibitory effect on oscillations, respectively. • Nearly 90% of neurones from 3 or 5-day-dehydrated rats exhibit oscillations. • More than 80% of OT-mRFP1 neurones from 3 to 6-day-lactating rats are oscillatory vs. about 44% in virgins., The magnocellular vasopressin (AVP) and oxytocin (OT) neurones exhibit specific electrophysiological behaviour, synthesise AVP and OT peptides and secrete them into the neurohypophysial system in response to various physiological stimulations. The activity of these neurones is regulated by the very same peptides released either somato-dendritically or when applied to supraoptic nucleus (SON) preparations in vitro. The AVP and OT, secreted somato-dendritically (i.e. in the SON proper) act through specific autoreceptors, induce distinct Ca2+ signals and regulate cellular events. Here, we demonstrate that about 70% of freshly isolated individual SON neurones from the adult non-transgenic or transgenic rats bearing AVP (AVP-eGFP) or OT (OT-mRFP1) markers, produce distinct spontaneous [Ca2+]i oscillations. In the neurones identified (through specific fluorescence), about 80% of AVP neurones and about 60% of OT neurones exhibited these oscillations. Exposure to AVP triggered [Ca2+]i oscillations in silent AVP neurones, or modified the oscillatory pattern in spontaneously active cells. Hyper- and hypo-osmotic stimuli (325 or 275 mOsmol/l) respectively intensified or inhibited spontaneous [Ca2+]i dynamics. In rats dehydrated for 3 or 5 days almost 90% of neurones displayed spontaneous [Ca2+]i oscillations. More than 80% of OT-mRFP1 neurones from 3 to 6-day-lactating rats were oscillatory vs. about 44% (OT-mRFP1 neurones) in virgins. Together, these results unveil for the first time that both AVP and OT neurones maintain, via Ca2+ signals, their remarkable intrinsic in vivo physiological properties in an isolated condition.

Alamandine (Ala1-Arg2-Val3-Tyr4-Ile5-His6-Pro7), a heptapeptide hormone of the renin-angiotensin system (RAS), exerts its effects through the Mas-related G-protein coupled receptor of the type D, MrgD, which is expressed in different tissues, including the brain. In the present study, we tested the hypothesis that alamandine could attenuate the depression-like behavior observed in transgenic rats with low brain angiotensinogen, TGR (ASrAOGEN)680. Transgenic rats exhibited a significant increase in the immobility time in forced swim test, a phenotype reversed by intracerebroventricular infusion of alamandine. Pretreatment with D-Pro7-Ang-(1-7), a Mas/MrgD receptor antagonist, prevented the antidepressant-like effect induced by this peptide demonstrating, for the first time, that alamandine through MrgD receptor, can modulate depression-like behavior in TGR (ASrAOGEN)680. This result shows an action of alamandine which strengthens the importance of the counter-regulatory arms of the RAS in fight and treatment of neuropsychiatric diseases.

International audience; Heavy chain-only antibodies (HCAbs) do not associate with light chains and their V H regions are functional as single domains, forming the smallest active antibody fragment. These V[H] regions are ideal building blocks for a variety of antibody-based biologics because they tolerate fusion to other molecules and may also be attached in series to construct multispecific antibodies without the need for protein engineering to ensure proper heavy and light chain pairing. Production of human HCAbs has been impeded by the fact that natural human V[H] regions require light chain association and display poor biophysical characteristics when expressed in the absence of light chains. Here, we present an innovative platform for the rapid development of diverse sets of human HCAbs that have been selected in vivo. Our unique approach combines antibody repertoire analysis with immunization of transgenic rats, called UniRats, that produce chimeric HCAbs with fully human V[H] domains in response to an antigen challenge. UniRats express HCAbs from large transgenic loci representing the entire productive human heavy chain V(D)J repertoire, mount robust immune responses to a wide array of antigens, exhibit diverse V gene usage and generate large panels of stable, high affinity, antigen-specific molecules.

Reports using fixed fibroblasts from familial and sporadic Alzheimer's disease (AD) patients indicated upregulated mitochondria-endoplasmic reticulum contacts (MERC) as a hallmark of AD. Despite its potential significance, the relevance of these results is limited because they were not extended to live neurons. Here we performed a dynamic in vivo analysis of MERC in hippocampal neurons from McGill-R-Thy1-APP transgenic (Tg) rats, a model of AD-like amyloid pathology. Live FRET imaging in Tg revealed perturbed “lipid-MERC” (gap width