Impact of cerebellar-specific genetic and circuit manipulations on the behavioral phenotype and cerebellar physiology in murine autism models

Clinical evidence suggests that developmental cerebellar injury and cerebello-cortical connectivity abnormalities are often present in autism. In mouse models, cerebellar-specific deletions of autism risk genes, or temporally constrained, developmental manipulations of cerebellar circuits, elicit autistic-like behaviors. Nonetheless, behavioral and electrophysiological findings are inconsistent within and across models. Additionally, while cerebellar manipulations during development can induce autistic phenotypes, studies of early cerebellar function and connectivity are scarce. In this review, we discuss the impact of cerebellar-specific genetic mutations and circuit manipulations on adult behavior and cerebellar neuronal activity in murine autism models. We also explore how cerebellar development can impact the establishment of mature circuits, and we consider the existing gaps regarding the use of murine models to elucidate the cerebellar role in autism.</p

Characterization of cutaneous and articular sensory neurons

Background: A wide range of stimuli can activate sensory neurons and neurons innervating specific tissues often have distinct properties. Here we used retrograde tracing to identify sensory neurons innervating the hind paw skin (cutaneous) and ankle/knee joints (articular), and combined immunohistochemistry and electrophysiology analysis to determine the neurochemical phenotype of cutaneous and articular neurons, as well as their electrical and chemical excitability. Results: Immunohistochemistry analysis using RetroBeads as a retrograde tracer confirmed previous data that cutaneous and articular neurons are a mixture of myelinated and unmyelinated neurons, and the majority of both populations are peptidergic. In whole-cell patch-clamp recordings from cultured dorsal root ganglion neurons, voltage-gated inward currents and action potential parameters were largely similar between articular and cutaneous neurons, although cutaneous neuron action potentials had a longer half-peak duration. An assessment of chemical sensitivity showed that all neurons responded to a pH 5.0 solution, but that acid-sensing ion channel (ASIC) currents, determined by inhibition with the non-selective ASIC antagonist benzamil, were of a greater magnitude in cutaneous compared to articular neurons. 40 – 50% of cutaneous and articular neurons responded to capsaicin, cinnamaldehyde and menthol, indicating similar expression levels of TRPV1, TRPA1 and TRPM8 respectively. By contrast, significantly more articular neurons responded to ATP than cutaneous neurons. Conclusion: This work makes a detailed characterization of cutaneous and articular sensory neurons, and highlights the importance of making recordings from identified neuronal populations: sensory neurons innervating different tissues have subtly different properties, possibly reflecting different functions.ISS was funded by an Erasmus for Graduate Students grant from the University of Coimbra. ZMAH and experiments were funded by an Arthritis Research Project Grant (Grant Reference 20930) to ESS. JDB was funded by a Corpus Christi College Study and Travel Grant. EStJS was funded by an Early Career Research Grant from the International Association for the Study of Pain. Thanks to Christoforos Tsantoulas for assistance with immunohistochemistry and members of the Smith lab for their technical assistance and help in preparing the manuscript.This is the final version of the article. It first appeared from SAGE via http://dx.doi.org/10.1177/174480691663638

Study of inks used in biomedical optics phantoms: stability and ageing

Inks are the most common absorbers added in phantoms for biomedical optics experiments. Due to the small quantities required, it is usual to prepare dilutions in distilled water and to store them for future use. However, they may degrade with time. This work investigates the stability, over a 60 day period, of various types of ink dilutions as a component used in tissue-mimicking phantoms. For this purpose, the optical properties, particularly the absorption coefficient, of a diffusive phantom fabricated with various pre-diluted inks have been determined by using time-resolved experiments, for the period of time under investigation. Two commercial India inks were studied, namely Rotring® and Higgins®, as well as a third type, a black ink-jet printer ink (Powertec®). Results suggest that all ink dilutions suffer from ageing, affecting the reproducibility of the optical properties of the phantoms. For the investigated period, this effect was more noticeable for the India inks, but almost negligible for the ink-jet printer ink.Fil: Pardini, Pamela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones En Física E Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Waks Serra, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones En Física E Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Ranea Sandoval, Hector Francisco. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Pomarico, Juan Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones En Física E Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Iriarte, Daniela Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones En Física E Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; Argentin

Theoretical investigation of photons partialpathlengths in multilayered turbid media

Functional near infrared spectroscopy (fNIRS) is a valuable tool for assessing oxy- and deoxyhemoglobin concentration changes (∆[HbO] and ∆[HbR], respectively) in the human brain. To this end, photon pathlengths in tissue are needed to convert from light attenuation to ∆[HbO] and ∆[HbR]. Current techniques describe the human head as a homogeneous medium, in which case these pathlengths are easily computed. However, the head is more appropriately described as a layered medium; hence, the partial pathlengths in each layer are required. The current way to do this is by means of Monte Carlo (MC) simulations, which are time-consuming and computationally expensive. In this work, we introduce an approach to theoretically calculate these partial pathlengths, which are computed several times faster than MC simulations. Comparison of our approach with MC simulations show very good agreement. Results also suggest that these analytical expressions give much more specific information about light absorption in each layer than in the homogeneous case.Fil: García, Héctor Alfredo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; ArgentinaFil: Vera, Demián Augusto. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; ArgentinaFil: Waks Serra, María Victoria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; ArgentinaFil: Baez, Guido Rodrigo. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; ArgentinaFil: Iriarte, Daniela Ines. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; ArgentinaFil: Pomarico, Juan Antonio. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentin

Cannabidiol modulates phosphorylated rpS6 signalling in a zebrafish model of tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is a rare disease caused by mutations in the TSC1 or TSC2 genes and is characterized by widespread tumour growth, intractable epilepsy, cognitive deficits and autistic behaviour. CBD has been reported to decrease seizures and inhibit tumour cell progression, therefore we sought to determine the influence of CBD on TSC pathology in zebrafish carrying a nonsense mutation in the tsc2 gene. CBD treatment from 6 to 7 days post-fertilization (dpf) induced significant anxiolytic actions without causing sedation. Furthermore, CBD treatment from 3 dpf had no impact on tsc2-/- larvae motility nor their survival. CBD treatment did, however, reduce the number of phosphorylated rpS6 positive cells, and their cross-sectional cell size. This suggests a CBD mediated suppression of mechanistic target of rapamycin (mTOR) activity in the tsc2-/- larval brain. Taken together, these data suggest that CBD selectively modulates levels of phosphorylated rpS6 in the brain and additionally provides an anxiolytic effect. This is pertinent given the alterations in mTOR signalling in experimental models of TSC. Additional work is necessary to identify upstream signal modulation and to further justify the use of CBD as a possible therapeutic strategy to manage TSC

Characterization of cutaneous and articular sensory neurons.

BACKGROUND: A wide range of stimuli can activate sensory neurons and neurons innervating specific tissues often have distinct properties. Here, we used retrograde tracing to identify sensory neurons innervating the hind paw skin (cutaneous) and ankle/knee joints (articular), and combined immunohistochemistry and electrophysiology analysis to determine the neurochemical phenotype of cutaneous and articular neurons, as well as their electrical and chemical excitability. RESULTS: Immunohistochemistry analysis using RetroBeads as a retrograde tracer confirmed previous data that cutaneous and articular neurons are a mixture of myelinated and unmyelinated neurons, and the majority of both populations are peptidergic. In whole-cell patch-clamp recordings from cultured dorsal root ganglion neurons, voltage-gated inward currents and action potential parameters were largely similar between articular and cutaneous neurons, although cutaneous neuron action potentials had a longer half-peak duration (HPD). An assessment of chemical sensitivity showed that all neurons responded to a pH 5.0 solution, but that acid-sensing ion channel (ASIC) currents, determined by inhibition with the nonselective acid-sensing ion channel antagonist benzamil, were of a greater magnitude in cutaneous compared to articular neurons. Forty to fifty percent of cutaneous and articular neurons responded to capsaicin, cinnamaldehyde, and menthol, indicating similar expression levels of transient receptor potential vanilloid 1 (TRPV1), transient receptor potential ankyrin 1 (TRPA1), and transient receptor potential melastatin 8 (TRPM8), respectively. By contrast, significantly more articular neurons responded to ATP than cutaneous neurons. CONCLUSION: This work makes a detailed characterization of cutaneous and articular sensory neurons and highlights the importance of making recordings from identified neuronal populations: sensory neurons innervating different tissues have subtly different properties, possibly reflecting different functions.ISS was funded by an Erasmus for Graduate Students grant from the University of Coimbra. ZMAH and experiments were funded by an Arthritis Research Project Grant (Grant Reference 20930) to ESS. JDB was funded by a Corpus Christi College Study and Travel Grant. EStJS was funded by an Early Career Research Grant from the International Association for the Study of Pain. Thanks to Christoforos Tsantoulas for assistance with immunohistochemistry and members of the Smith lab for their technical assistance and help in preparing the manuscript.This is the final version of the article. It first appeared from SAGE via http://dx.doi.org/10.1177/174480691663638

Diffuse reflectance optical topography: location of inclusions in 3D and detectability limits

In the present contribution we investigate the images of CW diffusely reflected light for a point-like source, registered by a CCD camera imaging a turbid medium containing an absorbing lesion. We show that detection of μa variations (absorption anomalies) is achieved if images are normalized to background intensity. A theoretical analysis based on the diffusion approximation is presented to investigate the sensitivity and the limitations of our proposal and a novel procedure to find the location of the inclusions in 3D is given and tested. An analysis of the noise and its influence on the detection capabilities of our proposal is provided. Experimental results on phantoms are also given, supporting the proposed approach.Fil: Carbone, Nicolás Abel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Baez, Guido Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: García, Héctor Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Waks Serra, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Di Rocco, Hector Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Iriarte, Daniela Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Pomarico, Juan Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; ArgentinaFil: Grosenick, D.. Physikalisch-Technische Bundesanstalt; AlemaniaFil: Macdonald, R.. Physikalisch-Technische Bundesanstalt; Alemani

Supplemental vitamin B-12 enhances the neural response to sensory stimulation in the barrel cortex of healthy rats but does not affect spontaneous neural activity

Background: Although vitamin B-12 (B-12) is known to contribute to the structural and functional development of the brain, it is unclear if B-12 supplementation has any beneficial effect in healthy populations in terms of enhanced neurological status of the brain or improved cognitive function. Objectives: We investigated the effect of dietary supplementation of B-12 on the cortical neural activity of well-nourished young adult rats and tested the hypothesis that B-12 supplementation in healthy rats may reduce sensory evoked neural activity due to enhanced inhibition. Methods: Female Lister Hooded rats weighing between 190g to 265g (2 to 4 months old) were included in the study. The experimental group was fed with B-12 (Cyanocobalamin) enriched water at a concentration of 1mg/L, and the control (CON) group with tap water for 3 weeks. Animals were then anaesthetised and cortical neural responses to whisker stimulation were recorded in vivo using a multi-channel micro-electrode, from which local field potentials (LFPs) were extracted. Results: Somatosensory evoked LFP was enhanced 25% in the B-12 group (4.13±0.24mV) compared with the CON group (3.30±0.21mV) (P=0.02). Spontaneous neural activity did not differ between groups; frequency spectra at each frequency bin of interest did not pass the cluster-forming threshold at the 5% significance level. Conclusions: These findings do not provide evidence supporting the hypothesis of decreased neural activity due to B-12 supplementation. As the spontaneous neural activity was unaffected, the increase in somatosensory evoked LFP may be due to enhanced afferent signal reaching the barrel cortex from the whisker pad, indicating that B-12 supplemented rats may have enhanced sensitivity to sensory stimulation compared to the CON group. We suggest that this enhancement might be the result of lowered sensory threshold, although the underlying mechanism has yet to be elucidated

Activated PI3Kδ syndrome, an immunodeficiency disorder, leads to sensorimotor deficits recapitulated in a murine model.

The phosphoinositide-3-kinase (PI3K) family plays a major role in cell signaling and is predominant in leukocytes. Gain-of-function (GOF) mutations in the PIK3CD gene lead to the development of activated PI3Kδ syndrome (APDS), a rare primary immunodeficiency disorder. A subset of APDS patients also displays neurodevelopmental delay symptoms, suggesting a potential role of PIK3CD in cognitive and behavioural function. However, the extent and nature of the neurodevelopmental deficits has not been previously quantified. Here, we assessed the cognitive functions of two APDS patients, and investigated the causal role of the PIK3CD GOF mutation in neurological deficits using a murine model of this disease. We used p110δE1020K knock-in mice, harbouring the most common APDS mutation in patients. We found that APDS patients present with visuomotor deficits, exacerbated by autism spectrum disorder comorbidity, whereas p110δE1020K mice exhibited impairments in motor behaviour, learning and repetitive behaviour patterning. Our data indicate that PIK3CD GOF mutations increase the risk for neurodevelopmental deficits, supporting previous findings on the interplay between the nervous and the immune system. Further, our results validate the knock-in mouse model, and offer an objective assessment tool for patients that could be incorporated in diagnosis and in the evaluation of treatments

One-Year Changes in Urinary Microbial Phenolic Metabolites and the Risk of Type 2 Diabetes—A Case-Control Study

The intake of polyphenols has been associated with a risk reduction of type 2 diabetes. Nevertheless, to the best of our knowledge, the molecules that might be metabolically active after ingestion are only starting to be investigated regarding this metabolic disease. To investigate the association between one-year changes in urinary microbial phenolic metabolites (MPM) and the incidence of type 2 diabetes, we performed a case-control study using data and samples of the PREDIMED trial including 46 incident type 2 diabetes cases of 172 randomly selected participants. Eight urinary MPMs were quantified in urine by liquid chromatography coupled to mass spectrometry and used to assess their associations with type 2 diabetes risk by multivariable logistic regression models. Compared to participants in the lowest tertile of one-year changes in hydroxybenzoic acid glucuronide, those in the highest tertile had a significantly lowered probability of developing type 2 diabetes (OR [95% CI], 0.39 [0.23–0.64]; p < 0.001 for trend). However, when additionally adjusting for fasting plasma glucose, the statistical significance was lost. Changes in the dietary pattern can increase the concentrations of this compound, derived from many (poly)phenol-rich foods, and might be changing the gut microbial population as well, promoting the production of the metabolite.This research was funded by CICYT [AGL2016-75329-R] PID2020-114022RB-I00, CIBEROBN Instituto de Salud Carlos III, ISCIII from the Ministerio de Ciencia, Innovación y Universidades, (AEI/FEDER 10.13039/501100011033, UE), and Generalitat de Catalunya (GC) [2017SGR196]. M.M.-M. is supported by the FPU17/00513 grant. I.D.-L. thanks the Spanish Ministry of Science Innovation and Universities for the Formación de Profesorado Universitario (FPU20/02478) contract. E.P.L.-S. is supported by the FI-SDUR (EM/3345/2020) grant from the Generalitat de Catalunya. I.P.-M. is supported by the FI-SDUR (EMC/2703/2019). Partial funding for open access charge: Universidad de Málaga