Abstracts – SEMINARS

Computational

1.  Agata Gut, Agnieszka Kazimierska, Magdalena Kasprowicz, Agnieszka Uryga
Department of Biomedical Engineering, Faculty of Fundamental Problems of Technology, Wroclaw University of Science and Technology, Wroclaw, Poland

Analysis of the relationship between cerebral autoregulation and arterial baroreceptor sensitivity

 cerebral autoregulation, baroreflex sensitivity, time-frequency representation

 

Cerebral autoregulation (CA) maintains adequate cerebral blood flow (CBF) in response to fluctuations in mean arterial blood pressure (ABP). The autonomic nervous system (ANS) helps regulate blood pressure, which in turn influences CBF. Despite intensive research, the link between CA and ANS remains a subject of ongoing debate. Our study aims to investigate this relationship in healthy subjects at rest. 

ABP was measured non-invasively using photoplethysmography, and cerebral blood flow velocity (CBFV) was assessed using transcranial Doppler ultrasonography in healthy young volunteers (approval: KB-179/2023/N). Data were recorded over a 5-minute resting period in the sitting position. CO2 levels were controlled during measurement. Baroreflex sensitivity (BRS), which describes a part of the ANS function, was estimated using pulse interval variability and systolic pressure variability in the time domain (xBRS), as well as using time-frequency (TF) representation (BRSTF) in the low-frequency range (0.04–0.15 Hz). CA was assessed using transfer function phase shift (PS) and gain between slow-wave oscillations (0.02-0.07 Hz) in CBFV and ABP. The relationships between analysed metrics were assessed using Spearman correlation coefficient (rS). This work was supported by the National Science Centre, Poland (grant no UMO-2022/47/D/ST7/00229).

21 subjects were included in the study (male/female: 38%/62%; median age [Q1-Q3]: 23 [21-25] years). Gain correlated significantly with BRSTF (rS=0.56, p=0.018) and xBRS (rS = 0.52, p = 0.033), indicating that poorer CA (i.e. smaller suppression of CBFV changes in response to ABP fluctuations) is associated with higher BRS (i.e. worse ANS function). A decrease in PS (i.e. worse CA) was also observed with increasing xBRS and BRSTF, but these associations were not statistically significant (rS= –0.20 and rS= –0.16, respectively).

Our preliminary findings suggest a reciprocal relationship between CA and BRS. Further research involving physiological stimuli and a larger group of subjects is needed to confirm those findings.

 

2. Monika Najdek, Cyprian Mataczyński, Małgorzata Burzyńska, Agnieszka Uryga
Wrocław University of Science and Technology

 The relationship between neuroparameters and autonomic nervous system metrics in traumatic brain injury patients using canonical correlation analysis

paroxysmal sympathetic hyperactivity, canonical correlation analysis, traumatic brain injury
 

Paroxysmal sympathetic hyperactivity (PSH) is a syndrome characterised by increased activity of the sympathetic nervous system following traumatic brain injury (TBI). Canonical Correlation Analysis (CCA) is a statistical technique that measures relationships between two sets of variables. Our aim was to investigate whether CCA of autonomic nervous system metrics: heart rate variability in the low-frequency range (HRV LF) and heart rate (HR) and neuroparameters: intracranial pressure (ICP) and pressure reactivity index (PRx) can differentiate between patients with likely and unlikely PSH.

The study was approved by the bioethical committee of Wroclaw Medical University (KB-133/2023) and supported by the National Science Centre, Poland (UMO-2022/47/D/ST7/00229). Signals of arterial blood pressure and ICP in 52 severe TBI patients, monitored for 24 hours, were retrospectively analysed. PSH diagnosis was performed using the Clinical PSH Assessment Measure. Patients were divided into cohorts of 5 and 47, corresponding to likely and unlikely PSH. Signal variables, including the amplitude, phase, and frequency of the main signal component, as well as coefficients of second-degree polynomial approximation and spectral entropy, were computed in 6-hour window with a 2-hour step. The first five components obtained by CCA were analysed.

The first canonical correlations for ICP vs HRV LF, PRx vs HRV LF, ICP vs HR and PRx vs HR were 0.78, 0.82, 0.74, and 0.72, respectively, in the likely PSH group, compared to 0.27, 0.27, 0.27, and 0.41, respectively, in the unlikely PSH group. The variables that had the greatest impact on canonical variates within these groups were the amplitude of the main signal component and the coefficients of second-degree polynomials.

The relationship between ANS metrics and neuroparameters, as analyzed using CCA, may significantly differ between patients with and without PSH. Further study on larger groups are needed to confirm these observations.

 

 

3. Emilia Kaczmarczyk, dr hab. Maciej Kamiński
Faculty of Physics, University of Warsaw

 Comparative Analysis of Alpha Rhythm Propagation in EEG Signals: Evaluating PCMCI+ versus Granger Causality Algorithms

Alpha rhythm, EEG signals, PCMCI+ algorithm, Granger causality, causal relationships, signal propagation, sampling frequency, Bayesian network, conditional independence

 

This research aims to investigate the propagation of the alpha rhythm in EEG signals using the PCMCI+ algorithm and to compare its effectiveness with Granger causality-based algorithms. The study focuses on how these algorithms perform in detecting causal relationships at different sampling frequencies (128 Hz, 512 Hz, 2048 Hz) and evaluates their ability to identify known causal relationships in both artificially generated and real EEG data. By comparing the two methods, we seek to determine whether PCMCI+ offers advantages in accuracy and reliability over traditional Granger causality approaches in analyzing EEG signal propagation.

This research uses the PCMCI+ algorithm to analyze the propagation of the alpha rhythm in EEG signals. PCMCI+ is a graph-based method that identifies causal relationships by iteratively performing conditional independence tests to build a Bayesian network. The results are compared to those from Granger causality-based algorithms, which assess causality based on the predictive power of past values.

The results indicate that the PCMCI+ algorithm can effectively identify some causal relationships in the propagation of the alpha rhythm at different sampling frequencies without time lag. In artificially generated data, the detected causal dependencies remained consistent across all sampling frequencies. However, in real EEG data, these dependencies were more dependant on the sampling rate due to noise. Apart from that, some granger causality test haven’t been conducted yet at this moment.

The preliminary findings suggest that the PCMCI+ algorithm may have advantages over Granger causality in detecting causal relationships in EEG signals, particularly at lower sampling frequencies. However, the study is ongoing, and more tests are needed to confirm these results. As the research is not yet complete, it is currently not possible to draw definitive conclusions about the effectiveness of PCMCI+.

 

Cognitive

1.  Helena Jabłonowska
Polish-Japanese Academy of Information Technology graduate

Semir Zeki’s Theory on concepts. Two animated viusal essays.

concepts, Semir Zeki, inherited concepts, acquired concepts, house concept, face concept, Francis Bacon, neuroaesthetics, deformation

Both animations will be shown at the end of the presentation sessions. 

Abstract for Concepts animation: 

The visual essay on the theory about concepts, based on the book „Splendors and Miseries of the Brain,” by Professor of Neuroaesthetics Semir Zeki. The theory explains how people acquire knowledge by creating brain concepts. The film explains acquired concepts through the example of a concept of house. The animation combines 2D and 3D techniques.  

Abstract for A conversation about faces animation: 

The animation script is based on Semir Zeki’s and Tomohiro Ishizu’s essay “The ‘Visual Shock’ of Francis Bacon: an essay in neuroesthetics,” where they progress the subject of inherited concepts on the example of faces and bodies. My film presents an animated discussion on the concept of the face. It also analyzes how viewers interpret the deformed faces portrayed in the works of British painter Francis Bacon, within the framework of the previously mentioned theory. The animation boldly combines a variety of techniques, from stop-motion animation (employing crayon, plasticine, monotype, and collage) to 3D methods. 

 

2.  Tymon Rochowski, prof. dr hab. Maciej Haman
University of Warsaw

Mental arithmetic is intrinsically linked with spatial attention.

Operational Momentum, Inhibition of Return, Numerical Cognition, Nonsymbolic Arithmetic, Spatial Attention 

This study explores the phenomenon of reversed Operational Momentum (OM) within the context of an Inhibition of Return (IOR) task, focusing on nonsymbolic arithmetic. OM is the tendency to overestimate outcomes in addition or underestimate them in subtraction, often associating these operations with the right or left side of space, respectively. Mental arithmetic has been linked to shifts in spatial attention along the Mental Number Line (MNL). A key marker of spatial attention is IOR, where individuals respond more slowly to stimuli in locations they have previously attended to. In some experimental setups, OM effects are reduced or even reversed, suggesting that IOR might play a role in mental arithmetic. This study aims to combine traditional OM and IOR designs to rigorously test the attentional hypothesis in arithmetic.

Twenty-eight participants solved nonsymbolic arithmetic tasks involving both addition and subtraction. Some trials were modified by adding a flashing lateral cue. In each trial, a group of dots was shown falling into a box. In addition trials, a second group of dots fell into the box; in subtraction trials, dots fell out. After the box opened, participants indicated whether the final number of dots was correct.

The study identified significant IOR effects on reaction times based on the arithmetic operation. In addition if the outcome was shown 300ms after cue flashing at right, reaction times were relatively slowed down; in subtraction cue at left had the same effect.

The influence of IOR on reaction times supports the attentional hypothesis in arithmetic. The IOR effect typically requires two spatially incongruent cues: one cue was a brief screen flash, and the arithmetic operation itself acted as a second cue on the same internal spatially organized numerosity representation. These findings suggest that spatial-numerical representations are crucial in shaping arithmetic processes.

 

3. Sofiia Honcharova, Wiktoria Orłowska, Renate Rutiku

Institute of Psychology, Jagellonian University 

Disentangling spatio-temporal attention from conscious perception with EEG and a novel behavioral approach


Perception, attention, electroencephalography, consciousness

 

Most studies have failed to dissociate exogenous attention and perceptual awareness on the behavioural (e.g. reaction times) and neural level (e.g. ERP components). This may stem from (1) the fact that current behavioural measures are not sensitive enough to capture subtle changes in, e.g., the time course of perception and (2) the problematic contrastive approach widely used in the analyses of electrophysiological data. The current work aimed to address these problems by using a novel measure of consciousness – the LAG.

The LAG task captures the subjective onset of awareness of a continuously changing stimulus. It has been confirmed that LAG values are not redundant with reaction times, and that the variance in LAG values is not due to subjects’ poor precision in estimating stimulus length. Here the LAG task was combined with an attentional cueing paradigm during which participants’ whole-head 64 channel EEG was recorded.

Previous research findings were replicated, confirming a strong link between exogenous attention and conscious perception. LAG ratings were more precise for right visual field target stimuli, while reaction times were quicker for left-side target stimuli. The time interval between cue and target stimulus was found to be the strongest predictor in all conditions. Importantly, it was found to explain more variability for reaction times than for LAG indicating a potential dissociation in the time course of attention-related processes and conscious perception. In the EEG, attentional effects were observed in both early and late time windows, whereas the LAG tended to correlate with EEG amplitude only in the late time windows.

The results indicate several ways in which attention and conscious perception can be dissociated on the behavioural and neural level. Further analysis should concentrate on EEG latencies to describe the temporal dynamics of attention vs consciousness in even more detail. 

 

4. Agnieszka Mankiewicz, Bartosz Miklaszewski, Joanna Rączaszek-Leonardi, Katarzyna Chyl, Julian Zubek, Agnieszka Dębska
University of Warsaw

The Neural Basis of Symbolic Representations: Insights from fMRI

 symbols, orthography, fMRI

 

The ability to use symbols is a key feature of human cognition. This study investigated neural correlates underlying the processing of abstract linguistic symbols using C.S. Peirce’s semiotic framework (Hartshorne et al., 1931). The experiment examined brain-level differences in processing three types of newly created signs: icons, indexes, and symbols, differentiated by their sign-object link – through resemblance, pointing attention, or conventional association. We explored whether brief exposure to new abstract symbols is enough to create the neural underpinnings for orthographic representation and whether this process depends on the newly acquired orthography level.

The brain activity during the artificial orthography learning task was investigated with functional magnetic resonance in 40 Polish adults (Mean age = 21,38; SD = 2,34). A short language localizer task was performed to identify the parts of the brain responsible for processing orthographic and phonological information in each subject. During the experimental task, participants were first shown abstract shapes and heard unfamiliar Armenian words separately (icons), followed by both modalities presented together (indexes), and finally presented simultaneously according to predefined rules (symbols). After scanning, participants evaluated auditory-visual stimulus combinations in a test to assess learning effects. Reading skills, attention, and working memory were also measured through onsite tests.

We have obtained preliminary results summarizing activations for icon signs in visual and auditory modalities, along with activity from pre-known conventional symbols. Analysis of results for previously unknown indexes and symbols acquired during the task is still in progress.

Based on the results, activations for newly introduced icons do not differ from simple visual or auditory stimuli responses. The familiar symbols activate a much broader set of structures, that apart from regions activated by icons, involve areas belonging to the language network. The visual and auditory symbols selectively activate separate language processing hubs.

 

Clinical & neurobiology

1. Jadwiga Zymer, Marcin Lipiec, Ewelina Knapska
University of Warsaw

New mouse ASD model with Tsc2 gene knockout – evaluation of tissue specificity of the mutation

autism spectrum disorder, neurodevelopmental disorder, mouse model of autism,
GABA,  conditional gene knockout, tuberous sclerosis

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterised by repetitive behaviours and deficits in social interaction. One possible component of ASD neurobiology is altered ratio between excitatory and inhibitory neurotransmission in the brain. In order to elucidate the relationship between ASD and altered function of inhibitory neurons, we recently developed a new mouse model with tissue-specific mutation of the Tsc2 gene (murine equivalent of the human gene associated with tuberous sclerosis, a genetic disorder highly comorbid with ASD). The mutation is introduced in all cells expressing GAD2, enzyme responsible for producing the inhibitory neurotransmitter GABA. The aim of my project was to evaluate tissue specificity of Tsc2 mutation in the new model by 1) confirming that the mutation is present in GABAergic neurons, and 2) identifying affected cells outside the brain.

The study was conducted on mice with cell type-specific Tsc2 knockout (KO) and wild-type conspecifics (WT). All mice expressed tdTomato reporter gene in Gad2-positive cells. Brains and selected non-neural tissues were isolated, fixed, sectioned and analysed with the use of fluorescent microscopy to identify cells affected by the mutation.

As expected, GABAergic inhibitory neurons are affected by the mutation. However, I also identified affected cells in numerous non-neural tissues, including sensory organs, gastrointestinal system, and kidney. Moreover, mice with the conditional Tsc2 knockout have enlarged brains, and one of them developed kidney tumours.

I have identified multiple cell populations affected by the Tsc2 mutation in the new ASD model. These findings should be taken into account while planning and analysing further research utilising the new strain: the Tsc2 mutation may have an effect not only on the function of inhibitory neurons, but also, among others, on sensory perception, renal, and gastrointestinal function.

 

2. Redwan Jabbar, Agnieszka Pawelczyk, Maciej Radek
Medical University of Lodz

Virtual reality-based exposure intervention as a digital pre-med to alleviate anxiety and pain in patients undergoing spine surgery: A Randomized Controlled Trial

Virtual Reality (VR), Anxiety, Spine Surgery

 

The overall prevalence of pre-operative anxiety varies and is reported in a range of 60-80% while other studies showed a wider range of 11-80% [1-5]. It occurs as a compatible response to surgical encounters and stress, which might occur anytime pre-operatively [6-8]. Pre-operative stress-related signs are associated with a potential change in patients’ psychological responses and hemodynamic parameters, including increased blood pressure and heart rate, that may pose a danger to the patients’ health [9]. Thus, these changes might affect the quality of anaesthesia and demand for analgesics, post-operative pain, and possible delirium [10-12].

Research studies have shown that addressing pain by therapeutic interventions (i.e., by interacting with immersive virtual reality) results in slower response to incoming pain signals [13]. Therefore, controlled pre-operative anxiety and decreased pain reduces hospital stay lengths, healthcare costs, and post-operative complications [14].

The study included 20 patients aged approximately 52 within virtual reality (VR) group and 56 within control group (14% Female and 86% Male). All participants within VR group qualified for spine surgery exposed to a preoperative 10-minute 360˚ video with immersive audio-visual environment describing pre-operative and post-operative experience through measuring STAI-S, VAS, and PSS-10. And postoperatively,  STAI-S, VAS and EVAN-G.

Statistically significant correlations were observed between preoperative and postoperative VAS ( p-val: 0,795), with preoperative anxiety  (p-val: 0,279)), depression (p-val: 0.739),  In this study, patients with preoperative VR exposure revealed better VAS scores and better functional outcome measured by postoperative satisfaction questionnaire (EVAN-G) ranging between 88-96 among all participants.

The results of this study suggest that postoperative pain, anxiety and functional outcome could be improved by certain selected psychosocial measurements. Therefore, further studies to address these associated psychosocial factors may help spine surgeons to better manage patients with overlapping spinal diseases and poor postoperative functional outcome and pain. 

 

 

3. Aleksandra Pogoda-Wesołowska, Ignacy Stachura, Adam Stępień,
dr hab. n. med. Jacek Staszewski i lek. med. Marzena Maciągowska-Terela
University of Warsaw

Impact of reconstitution therapies – cladribine tablets and alemtuzumab – on the atrophy progression among patients with multiple sclerosis.
 

computational modelling, connectivity, event-related fields, evolutionary algorithms, feedback, feedforward, human auditory cortex, magnetoencephalography, optimisation

Immune reconstitution therapies (IRT) such as cladribine tablets (CLAD) and alemtuzumab (ALEM) are among the highly effective therapies (HET) of multiple sclerosis (MS). Today, it is known that these therapies are effective in controlling the relapsing activity and the progression of clinical disability. However, most of the data assessing the impact of IRT on the neurodegenerative process, is lacking.

The aim of the study was to evaluate the effect of IRT, CLAD and ALEM, on the degree and pattern of brain atrophy in patients with multiple sclerosis over a 3-year follow-up period.

Patients with relapsing remitting MS (RRMS) treated with CLAD and ALEM were retrospectively recruited for the study. Demographic, clinical, and magnetic resonance imaging (MRI) data were collected at 4 time points: before treatment and 1, 2, and 3 years after treatment. MRI exams underwent volumetric analysis using Free Surfer software. 

Data were collected from 33 patients (9 with all 4 MRI images) in the CLAD group and 19 (7 with all 4 MRI images) patients in the ALEM group. Totally 152 MRI images were analyzed. Over the 3-year period, overall brain atrophy was similar between the two groups, with a reduction of -1.19% in the CLAD group and -1.16% in the ALEM group. However, significant differences were observed in specific brain regions, namely the hippocampus and amygdala. The ventral diencephalon was the only region to show a significant decrease in both groups, demonstrating the least variability among subcortical structures.

Differences in the progression of brain atrophy over the 3 years were also noted. In the CLAD group, atrophy steadily declined, starting from -0.68% in the first year and reaching no significant atrophy by the third year. In contrast, the ALEM group exhibited the greatest atrophy in the third year, with a decrease of -0.68%.

In the studied patient groups, both immune reconstitution therapies (IRT) resulted in similar overall brain atrophy over a 3-year period in MS patients, but they differed significantly in their impact on regional brain volume changes. The ventral diencephalon showed significant atrophy in both treatment groups, suggesting its potential importance in the progression of MS.

 

 

4. Maja Wójcik, Agata Chrobak, Arkadiusz Dudek , Aleksandra Bolek, Paweł Kubicki,
Lucyna Pomierny-Chamioło, Michał Wierzchoń, Justyna Hobot, Maciej Pilecki, Grzegorz Kazek 
Jagiellonian University, Institute of psychology

Linking aspects of cognitive functioning and neuroprotein plasma levels in psychedelic users

neuroproteins, psychedelics, cognitive functions
 

The need to research the long-term influence of psychedelics on neurobiological and cognitive functioning of their users stems from their increasingly widespread use and significant gaps in knowledge about their effects. Psychedelics act mainly as agonists for the 5-HT2A receptors, affecting serotonergic transmission and therefore – numerous biological processes. The serotonergic system plays a crucial role in various cognitive aspects such as memory, attention, spatial navigation, and decision-making. The influence of psychedelics on various proteins that are of essential importance in neurobiological functions and their links to cognitive functioning remain unclarified, especially in naturalistic users (outside of the laboratory context). Accordingly, the aim of the study was to examine the cognitive functions of naturalistic psychedelic users and the levels of selected neural proteins, along with analyzing their interrelations. We also aimed to check whether effects from psychedelic clinical studies would replicate on naturalistic users.

Cognitive functions were measured in 46 psychedelics users using the Cogstate battery of behavioral tests (GML, GMR, IDN, OCL, SETS, TWOB, DET). Protein analyses (BDNF, NRG1B1, PDGF-AB) were performed in blood plasma using xMAP technology with simultaneous quantitative determination of multiple proteins in a single sample. Then, Spearman’s non-parametric correlations with confidence intervals bootstraped (10 thousand times) were conducted for all variables and with control for age, cannabis use and other psychoactive substances use.

Some cognitive function parameters showed significant correlations with the protein concentrations: GMR with BDNF, PDGF-AB, and NRG1B1, SETS correlated with BDNF and PDGF-AB, and OCL with BDNF. No statistically significant differences were found between the users and non-users group in terms of the results of cognitive function tests. The number of lifetime psychedelics uses correlated only with BDNF levels.

This study is the first to demonstrate the links between these proteins and the cognitive tests of the Cogstate battery. Our results indicate that clinical and animal studies can’t be that highly extrapolated on naturalistic users of psychedelics. There are many differences between people using naturalisticly and people recruited for clinical studies. This has significant clinical implications for healthcare professionals, especially psychiatrists and psychotherapists. They also show that psychedelics might be relatively safe in terms of long term changes in cognitive functioning, but further research is required to confirm these findings.

Neurobiology

1. Katarzyna Sawicka, Monika Falińska, Rafał Czajkowski
Nencki Institute of Experimental Biology

Cortical Reinstatement is a direct approach to testing hippocampal indexing theory.

episodic memory, retrosplenial cortex, hippocampus, in vivo imaging, optogenetics

This research was done on mice, wild type and TRAP2. During stereotaxic surgery, we did cranial window above the retrosplenial cortex, injected viral vectors (pAAV-CamKIIa-C1V1(t/t)-mScarlet-KV2-cortex, pAAV-EF1a-double floxed-hChR2(H134R)-mCherry-WPRE-HGHpA-hippocampus, pAAV.Syn.GCaMP6f.WPRE.SV40-cortex)  to the hippocampus and retrosplenial cortex, and optic fiber were implanted. We perform optogenetics stimulation using LED diode and optic fiber. For in vivo imaging we used coordinated system with 2photon microscope and laser for optogenetic stimulation. 

Optogenetic stimulation of cortical random neuronal population (creating index) led to increased c-fos protein expression in the hippocampus, that suggests c-fos is a marker of hippocampal index. 

We found that significant colocalization C-fos/Chr2 in the hippocampus

Reactivation of c-fos protein+ cells by optogenetic activation of Channelrhodopsin in the hippocampus caused activation of GCaMP/C1V1 cells in the cortical area.

 

2.Gabriela Stopka1, 2, Aleksandra Trenk1, Anna Gugula1, Kinga Przybylska1, 2, Aleksandra Nogaj1, 2, Andrew L. Gundlach3 and Anna Blasiak1

1Department of Neurophysiology and Chronobiology, Institute of Zoology and Biomedical Research, Jagiellonian University, Krakow, Poland
2Doctoral School of Exact and Natural Sciences, Jagiellonian University, Krakow, Poland
3The Florey Institute of Neuroscience and Mental Health, and Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia


 RLN3/RXFP3 signaling in the ventral dentate gyrus – a novel neuronal substrate in control of stress and anxiety related processes

relaxin-3, ventral hippocampus, dentate gyrus, nucleus incertus, stress, anxiety

 

The ventral hippocampus (vHPC) is a crucial brain structure involved in processing contextual information and controlling stress and anxiety. Particularly, the ventral dentate gyrus, part of the vHPC, is strongly implicated in anxiety disorders. The vHPC remains under the control of innervation from the brainstem nucleus incertus (NI), whose neurons display remarkable sensitivity to stress. In addition, the NI is the main source of the neuropeptide relaxin-3 (RLN3), and activation of its receptor, RXFP3, modulates stress- and anxiety- related behaviours. Importantly, RXFP3 is mainly expressed on vDG interneurons that control vDG granule cells (GCs) activity. However, the role of the RLN3/RXFP3 signaling in shaping the activity of the vDG remains largely unknown. Therefore, this study focused on the impact of RLN3 on GCs excitability ex vivo and the anatomical features of NI – vDG innervation. 

The electrophysiological whole-cell patch clamp method was used to determine the effect of RLN3 on GCs excitability. Furthermore, viral-based neural tract-tracing and  fluorescence in situ hybridization were conducted to define the neurochemical features of NI – vDG inputs. 

The whole-cell patch-clamp studies revealed modulatory effects of RLN3 (100 nM) on GCs excitability. Viral-based neural tract-tracing and fiber density analysis revealed co-localization of RLN3-positive and NI-originating fibers, distributed across individual layers of the vDG. Moreover, fluorescence in situ hybridization showed that RXFP3 mRNA is expressed by vDG parvalbumin- and somatostatin-positive interneurons. 

In conclusion, our data suggests that RLN3 originating mainly from the brainstem NI can modulate GCs activity through activation of RXFP3 on specific hilar interneurons. The obtained electrophysiological and anatomical findings indicate possible role of RLN3/RXFP3 signaling within the vDG in control of anxiety and stress related behaviours.

Funding: National Science Centre, Poland grants UMO-2018/30/E/NZ4/00687, UMO-2023/49/B/NZ4/01885 and MiniGrant2023-ID.UJ.

 

3.  Andrzej Łach, Karolina Przepiórska-Drońska, Bernadeta A. Pietrzak Wawrzyńska, Małgorzata Kajta, Agnieszka Wnuk 
Instytut Farmakologii im. Jerzego Maja Polskiej Akademii Nauk 

Neuroprotective Efficacy of PaPE-1 in Post-Treatment of Hypoxic and Ischemic Injuries: Mechanisms and Therapeutic Potential

Ischemic stroke, hypoxia, in vitro cell cultures, estrogen receptors

Pathway Preferential Estrogen-1 (PaPE-1) is a novel compound designed to target non-nuclear estrogen receptors (ERs), and its neuroprotective effects present a promising path for developing therapeutic strategies for pathologies of nervous system associated with  hypoxia and ischemia, such as perinatal asphyxia and ischemic stroke. This study investigates the mechanisms of action of PaPE-1 and further substantiates its effectiveness in mitigating injuries caused by hypoxic and ischemic events. Notably, this study focuses on PaPE-1 effects in post-treatment paradigm, addressing the time-dependent limitations of existing therapies targeting the abovementioned pathologies.

In our research we employed an in vitro model of hypoxic/ischemic injury, constituted by subjecting primary neocortical cell cultures to hypoxic or ischemic conditions for 6 hours, followed by 18 hours of reoxygenation with PaPE-1, reflecting the reperfusion phase occurring in vivo. 

In our findings, administering PaPE-1 six hours post-injury effectively restored parameters disrupted due to hypoxia and ischemia. This included a reduction in cell death, an increase in cell survival, and the restoration of neurite outgrowth. Additionally, PaPE-1 positively influenced neurodegenerative processes, such as neuroinflammation, excitotoxicity and oxidative stress-induced DNA/RNA damage. In hereby work we also prove that the neuroprotective mechanisms of PaPE-1 are linked to the activation of kinases mTOR and MEK1/2, while pathways involving JNK and p38/MAPK remain unaffected. Furthermore, PaPE-1 was able to partially normalise the gene expression of factors related to neuronal damage (such as Mmp2, Mmp9 and Hif1a) and neuroinflammation (such as Il1b and Il10). 

This data strongly suggest that PaPE-1 is a promising candidate for protecting neurons from hypoxic and ischemic damage, even when treatment is initiated several hours after the initial injury.

 
 

4. Bernadeta A. Pietrzak-Wawrzyńska, Agnieszka Wnuk, Karolina Przepiórska-Drońska, Andrzej Łach, Małgorzata Kajta 
Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Laboratory of Neuropharmacology and Epigenetics, Smętna Street 12, 31-343, Krakow, Poland


Selective activation of non-nuclear estrogen receptors partially reverses amyloid-β-induced autophagy deficits in primary neuronal cell cultures

Alzheimer’s disease, neuroprotection, autophagy, primary neuronal cell cultures, estrogen receptors
 

Alzheimer’s disease (AD) is characterized by amyloid-β (Aβ) accumulation and tau hyperphosphorylation, leading to cognitive decline and memory loss. Estrogen receptors (ERs) are recognized for their neuroprotective role. Recent research distinguishes the activation of nuclear ER from non-nuclear ER, with the latter being a safer option that avoids the cardiovascular and cancer risks associated with nuclear ERs. Apoptosis and autophagy, along with their interaction, are crucial in AD pathology. We previously demonstrated that PaPE-1, a selective activator of non-nuclear ER pathways, effectively counteracts Aβ-induced apoptosis. However, its impact on autophagy has not been explored.

We modeled AD using mouse primary neocortical cell cultures exposed to Aβ oligomers for 24 hours. PaPE-1 was then administered for 6 hours. We assessed the effects of Aβ and PaPE-1 on autophagy. Autophagy inhibitors (SBI-0206965, Spautin-1, MRT68921, and Temsirolimus) were used to evaluate the effects of autophagy reduction on Aβ-induced caspase-3 elevation. CYTO-ID staining was employed to analyze autophagosome and autophagolysosome formation, while western blot and qPCR were used to measure protein and mRNA expression of autophagy-related factors ATG5/Atg5, NUP62/Nup62, AMBRA1/Ambra1 and MAP1LC3AB/Lc3a, Lc3b.

Our findings indicate that inhibiting autophagy-related factors Spautin-1 and MRT68921 increases apoptosis, highlighting the interplay between these processes in the utilized model. Aβ exposure reduced autophagosome and autophagolysosome formation, while PaPE-1 partially reversed this effect. Additionally, Aβ caused dysregulation of autophagy evidenced by decreased MAP1LC3AB levels, which PaPE-1 effectively upregulated, along with increases in Atg5, Ambra1, and Lc3b expression.

Aβ induces autophagy deficits, and in the utilised model autophagy inhibition may exacerbate apoptosis. Crucially, PaPE-1 partially counteracts Aβ-induced autophagy deficits, positioning it as a promising neuroprotective strategy against amyloid-β toxicity.

This research was funded by National Science Centre of Poland, grant number 2020/39/NZ7/00974

5. Magdalena Gomółka, Weronika Tomaszewska, Adria-Jaume Roura Canalda, Sandra Binias, Regina Nadalinskaya, Ali Jawaid
Nencki Institute of Experimental Biology PAS

The role of lipid metabolism and circulating miRNAs in the intergenerational transmission of the effects of parental adverse childhood experiences

epigenetic inheritance, miRNA, ACE, trauma, lipidmetabolism

 

Adverse childhood experiences (ACE) are associated with detrimental effects on adult physical and mental health. Emerging evidence suggests that behavioral and metabolic perturbations associated with ACE are transmissible across generations. However, the exact mechanisms underlying the effects of ACE on germline for such intergenerational transmission of symptoms remain elusive. Synergizing parallel investigation in a mouse model of ACE induced via unpredictable maternal separation and unpredictable maternal stress (MSUS) and human ACE cohorts, we hypothesize that lipid-associated microRNAs (miRNAs) communicate the effects of ACE to the germline for intergenerational transmission.

Small RNA sequencing (sRNA-seq) followed by RT-qPCR was performed on human ACE cohorts. Parallel investigations in mice involved intergenerational phenotyping after MSUS, as well as lipid-modifying interventions high-fat diet (HFD) and voluntary exercise (VE). Phenotyping included the elevated plus maze test, novel object recognition test and glucose tolerance test. Furthermore, miRNA carriers were isolated from each group and injected (intravenous tail injections) into male control and MSUS mice, which were then bred with naïve females.

sRNA-seq revealed overlapping miRNA changes in the serum collected from children, as well as the sperm from adult men with a history of ACE. Importantly, the differentially expressed miRNAs were closely connected to lipids, both in terms of their transport and regulatory functions. Offspring of both MSUS- and HFD-exposed male mice showed impaired glucose tolerance and behavioral deficits. Notably, cross-injections from MSUS into control mice recapitulated the offspring phenotype associated with MSUS, whereas, cross-injections from VE mice into MSUS mice partially mitigated the metabolic phenotype associated with MSUS.

Together, these studies provide proof-of-concept for the role of lipids and circulating miRNAs in communicating the effects of ACE to the germline for intergenerational sequelae.