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. 2025 Jun 19;85(3):e22986. doi: 10.1002/dneu.22986

Neonatal NLRP3 Inflammasome Activation Leads to Perineuronal Net Deficits in Early Adulthood

Emre Tarakcioglu 1,2, Bilgesu Genc 1,2, Kemal Ugur Tufekci 1,3,4, Sermin Genc 1,2,5,✉
PMCID: PMC12179493  PMID: 40538102

ABSTRACT

Perineuronal nets (PNNs) are specialized extracellular matrix structures that surround certain neurons and play a critical role in protecting neurons from oxidative stress and maintaining synaptic stability in the central nervous system. They have roles in memory formation, and their loss has been linked to various mental alterations, such as anxiety, depression, and schizophrenia. While immune activation is known to degrade PNNs, it remains unclear whether inflammasomes are involved in PNN formation dynamics during neuronal development, where cases of sepsis are particularly high. In this study, we investigated how activation of the NLRP3 inflammasome in neonatal mouse brains influences PNNs. To explore this, neonatal wild‐type and Nlrp3 knockout mice were injected with lipopolysaccharide (LPS) or phosphate‐buffered saline (PBS) on postnatal day (PND) 9, and PNNs were visualized at early adulthood (PND60). In addition, NLRP3 inflammasome activation was confirmed on PND10, and behavioral tests were performed on PND60. LPS treatment in wild‐type mice reduced PNN‐positive neurons in the hippocampus and cortex compared to the PBS group, whereas Nlrp3 knockout mice showed no differences between treatment groups. Moreover, behavioral tests revealed that neonatal LPS injection resulted in anxiety‐ and depressive‐like behavior and that NLRP3 deficiency restrained this effect. These results highlight the key role of NLRP3 inflammasome activation in inflammation‐driven PNN reduction during neuronal development. NLRP3 inhibitors could thus serve as potential therapeutic agents to protect the neuronal extracellular matrix from inflammatory damage in early life.

Keywords: inflammasome, NLRP3, neonatal inflammation, neuroinflammation, perineuronal net

1. Introduction

Inflammasomes are key mediators of inflammation, which initiate secretory and inflammatory pathways when specific pathogen‐ or damage‐associated molecular patterns are detected (Schroder and Tschopp 2010). The well‐characterized NLR family pyrin domain containing protein 3 (NLRP3) inflammasome contributes to inflammation‐associated central nervous system (CNS) pathologies like Alzheimer's disease, multiple sclerosis, and meningitis (Eren and Ozoren 2019). For substantial activation of the NLRP3 inflammasome, a priming step that elevates the levels of NLRP3 inflammasome complex proteins is necessary. This priming is mediated by the nuclear translocation of the transcription factor NF‐κB (nuclear factor kappa‐light‐chain‐enhancer of activated B cells), which is triggered mainly by toll‐like receptor signaling (by pathogen‐associated molecules, such as lipopolysaccharide [LPS]) or pro‐inflammatory cytokines like interleukin‐1β (IL‐1β) and tumor necrosis factor‐alpha (T. Liu et al. 2017). The activation phase of the NLRP3 inflammasome can be triggered by several molecular signals, like extracellular adenosine triphosphate, particle aggregates, potassium efflux, and reactive oxygen species (ROS) (Jo et al. 2016; Latz et al. 2013). Once triggered by these signals, NLRP3 proteins undergo self‐oligomerization and consequently recruit adaptor proteins called apoptosis‐associated speck‐like protein containing a CARD (ASC). The ASC proteins clustered on the NLRP3 complex then mobilize multiple caspase‐1 proteins, which become active by undergoing proximity‐induced cleavage. Caspase‐1 cleaves the pore‐forming protein Gasdermin‐D (GSDMD) and the inactive forms of the inflammatory cytokines IL‐1β and IL‐18. These inflammatory mediators are released through pores in the cell membrane formed by active GSDMD, causing paracrine inflammatory signaling (Franklin, Latz, and Schmidt 2018; Voet, Srinivasan, Lamkanfi, and van Loo 2019).

Perineuronal nets (PNNs) are net‐like extracellular matrices composed of proteins and glycosaminoglycans that surround the somas of a subpopulation of neurons in the CNS. They maintain neuronal integrity by protecting neurons from ROS and stabilizing their synaptic connections. Because of these synapse‐stabilizing and antioxidant roles, PNNs are critical for the long‐term function of neurons (Fawcett et al. 2019). They are crucial in the consolidation of memories such as place preference and fear memory (Gogolla et al. 2009; Slaker et al. 2015; Thompson et al. 2018), and their loss has been linked to anxiety‐ and depressive‐like behavior in rodents (Li et al. 2024; Yu et al. 2020), as well as schizophrenia in humans (Enwright et al. 2016). Immune activation in the adult mouse brain, induced by various inflammatory triggers such as ketamine and light (Venturino et al. 2021), ROS (Cheung et al. 2024), spared nerve injury (Tansley et al. 2022), amyloid, or tau aggregates and LPS (Crapser et al. 2020; K. Liu et al. 2025) has been shown to degrade PNNs. However, the role of inflammasomes in this degradation has not been investigated yet. It is also unknown whether inflammasome activation during the neonatal development of the brain has a long‐term effect on PNNs. This question is of clinical interest due to the high number of infections and sepsis cases in neonates compared to other age groups (WHO 2020).

In line with the issues mentioned above, this study aimed to determine the role of neonatal NLRP3 inflammasome activation in inflammation‐mediated PNN reduction in the brain. To address this question, we performed LPS injections in wild‐type (WT) and NLRP3 knockout mice at PND9, followed by PNN analysis in hippocampal and cortical brain sections at PND60. We also evaluated the long‐term behavioral effects of our model with forced swim test (FST), tail suspension test (TST), and open field test (OFT).

2. Materials and Methods

2.1. Animals

The animals in the study were maintained in the Izmir Biomedicine and Genome Center (IBG) Vivarium. All mice were housed in standard animal housing rooms at 22±2°C temperature and had free access to food and water. The rooms were exposed to a 12‐h light/12‐h dark cycle. For the experiments, wild‐type (WT) mice (strain: C57BL/6J, RRID:IMSR_JAX:000664) obtained from IBG and Nlrp3 knockout (NLRP3 KO) mice obtained from the Jackson Laboratory (strain: B6.129S6‐Nlrp3tm1Bhk/J, RRID:MGI:5465029) were used. Mice of both sexes were used in the experiment.

Our in vivo model in neonatal mice was performed on postnatal day (PND) 9 with an intraperitoneal injection of 1 mg/kg LPS (LPS from E. coli 055: B5, Sigma‐Aldrich, L2880), with an equal volume of phosphate‐buffered saline (PBS) (Biowest, L0615) injected in the control group (Lalancette‐Hebert et al. 2017). On the following day, half of the mice were sacrificed for confirmation of inflammasome activation by decapitation after transcardiac cold PBS perfusion under isoflurane anesthesia (n = 5). The remaining mice were sacrificed at PND60 after behavioral experiments (n = 5) (Figure 1a).

FIGURE 1.

FIGURE 1

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LPS triggers NLRP3 activation in neonatal (PND10) mouse brains. (a) Timeline of the experimental procedure in mice. (b) Representative western blots. (c) Normalized band intensities for NLRP3, (d) ASC, and (e) IL‐1β in mouse brain homogenates 24 h after injection of LPS (1 mg/kg (n = 5, *p < 0.05, ***p < 0.001).). NLRP3 KO, NLRP3 knockout; WT, wild‐type.

Brains obtained from the sacrificed mice were divided into two hemispheres. The right hemispheres were flash‐frozen in liquid nitrogen and stored at −80°C for western blot analyses. The left hemispheres were immersed in 4% paraformaldehyde in PBS (4% PFA) to fix the tissue for immunofluorescence staining.

2.2. Behavioral Tests

For measuring anxiety‐like and depressive‐like behavior in PND60 mice, the FST, the TST, and the OFT were utilized (Boyko et al. 2019).

In OFT, the mice were placed in boxes 20 cm deep, 26 cm wide, and 40 cm long, divided into 40 (5 × 8) equal‐sized squares. The movements of the mice were recorded from above for 8 min. The boxes were cleaned with 70% ethanol and dried between each recording. Time spent in the central 3 × 6 square zone was recorded and used to measure reduced anxiety (Prut and Belzung 2003).

In TST, each animal was taped by its tail and allowed to hang freely while being recorded for 8 min. The mice were isolated from other mice. The latency to immobility for each animal was recorded as the time the mice stayed motionless for 5 s.

In FST, mice were placed inside a large beaker (25 cm tall with a 15‐cm diameter) filled three‐fourths with water and recorded for 8 min. The water was changed between each recording. Immobility was defined as floating in the water without movement for at least 5 s, and latency to immobility was recorded for each animal.

2.3. Protein Isolation and Western Blot

Brains were lysed in RIPA lysis solution (ThermoFisher Scientific, 89900) containing 1% Halt protease and phosphatase inhibitor cocktail (ThermoFisher Scientific, 78447). Afterward, tissue lysis was performed with an electromechanical homogenizer. The brain homogenates were incubated on ice for 2 h and then centrifuged at 16,000× g at 4°C to acquire the protein. A bicinchoninic acid protein assay kit (Elabscience, E‐BC‐K318‐M) was used to assess the protein amount in each sample.

For the western blot, equal amounts of protein were loaded and separated using SDS‐PAGE gels. Next, proteins were transferred from the gels to polyvinylidene difluoride (PVDF) membranes and blocked with TBST (Tris‐buffered saline with 0.01% Tween‐20) containing 3% milk. Following blocking, membranes were treated with relevant primary antibodies (Anti‐NLRP3, Adipogen, Cat# AG‐20B‐0014, RRID:AB_2490202, 1:800 in 3% bovine serum albumin [BSA]; Anti‐IL‐1β, Abcam, Cat# ab9722, RRID:AB_308765, 1:400 in 1% milk; Anti‐β‐Actin, Cell Signaling Technology, Cat# 8457, RRID:AB_10950489, 1:1000 in 3% BSA) overnight. β‐Actin antibody was used as a gel loading control. The next day, after washing three times with TBST, membranes were incubated with corresponding secondary antibodies coupled with horseradish peroxidase (Anti‐Mouse IgG, Cell Signaling Technology, Cat# 7076, RRID:AB_330924, 1:1000 in 3% Milk; Anti‐Rabbit IgG, Jackson ImmunoResearch, Cat# 111‐035‐144, RRID:AB_2307391, 1:1000 in 3% Milk) for 1 h. Following three TBST washes, the membranes were imaged using a chemiluminescent substrate (SuperSignal West Pico PLUS Chemiluminescent Substrate, ThermoFisher Scientific, 34577) and the ChemiDoc MP Imaging System. Image Studio Lite (LI‐COR Biosciences, RRID:SCR_013715) was used to determine the intensities of the protein bands.

2.4. Immunofluorescence Staining

In order to stain mature neurons, antibodies against microtubule‐associated protein 2 (MAP2) were used (De Camilli et al. 1984). PNN labeling was performed with fluorescein‐conjugated Wisteria floribunda agglutinin (WFA), which binds to the N‐acetyl‐galactosamine group of the chondroitin sulfate proteoglycans of PNNs (Hartig, Brauer, and Bruckner 1992).

Following PFA fixation, brains were placed in a 15% sucrose solution in PBS for tissue dehydration. After the brains sank to the bottom of the solution, they were moved into a 30% sucrose solution. After approximately 24 h at 4°C, the brains sank to the bottom of the 30% sucrose solution. They were removed, placed in plastic cuvettes filled with optimal cutting temperature (OCT) compound, and frozen at −80°C. Afterward, 10‐µm coronal sections of the hippocampus and neighboring areas were acquired via a cryostat, and sections were transferred onto adhesive slides. Thirty sections from each animal were obtained with a 20 µm space between each section, and three sections from each animal were selected for immunofluorescent staining via an online random number generator, using a range of 1–30.

For post‐sectioning immunofluorescence procedures, the OCT compound was removed from slides, and samples were contoured with a PAP pen. The samples were then fixed and permeabilized with cold acetone at −20°C for 10 min, washed shortly in PBS, and kept in a blocking and permeabilization solution of 5% donkey serum (PAN Biotech, P30‐0101) and 0.2% Triton‐X‐100 (in PBS) for 1 h. Afterward, MAP2 antibody (ThermoFisher Scientific, PA1‐10005, RRID:AB_1076848, 1:1000) or WFA (ThermoFisher Scientific, L32481, 1:300) was added to samples in “tissue staining solution” (1% donkey serum, 0.2% Triton‐X‐100 in PBS), and the slides were incubated overnight in humidified chambers at 4°C. The next day, slides were washed three times with PBS, kept for 1 h at room temperature with secondary antibody (Anti‐Chicken IgY Alexa Fluor 568, ThermoFisher Scientific, A78950, RRID:AB_2921072, 1:1000) with Hoechst (Hoechst 33342, AppliChem, A0741, 1 µg/mL) in tissue staining solution, washed three times with PBS and one time with distilled water. Slides were then covered with coverslips after applying a mounting medium (ThermoFisher Scientific, P36980). After curing in the dark, the slides were sealed and visualized at 20× magnification with a fluorescence microscope (Olympus, BX61). Olympus cellSens Software (RRID:SCR_014551) was used for the image capture, and the images were taken at the high contrast setting and exposure levels of 60–80 ms.

Analysis and processing of the images were performed using ImageJ (RRID:SCR_003070). Cell bodies surrounded by WFA were considered “WFA‐positive” (WFA+) (Lupori et al. 2023; Venturino et al. 2021). For each mouse, three unique sections were used, and images of hippocampal regions (CA3, CA2 and CA1) and the somatosensory cortex were captured for each section. Thus, for each mouse, there were nine hippocampal and three cortical counts.

2.5. Statistical Analyses

Statistical analyses and graph generation were performed in GraphPad Prism (version 8, RRID:SCR_002798). Data are presented as mean ± standard error of the mean (SEM). The normality of the data was determined by the Shapiro–Wilk test. Comparisons between two groups where both distributions are normal were analyzed using the Student's t‐test. Comparisons between two groups with at least one non‐normal distribution were analyzed using the Mann–Whitney U test. Comparisons between more than two groups with normal distribution were analyzed using ANOVA with Bonferroni correction, and comparisons between more than two groups with non‐normal distribution were analyzed with the Kruskal–Wallis test. The statistical significance threshold was set at p < 0.05.

3. Results

3.1. LPS Injection in the Neonatal Period Activates NLRP3 Inflammasome

Neonatal mice injected with LPS or PBS on PND9 were sacrificed the next day (Figure 1a), and levels of NLRP3 and IL‐1β were determined in the brain homogenates. Both NLRP3 and IL‐1β were significantly increased in the LPS mice, indicating NLRP3 inflammasome activation (Figure 1b–e). NLRP3 levels were increased 48‐fold (Figure 1c), ASC levels were increased twofold (Figure 1d), and IL‐1β levels were elevated threefold (Figure 1e) in the LPS group brains compared to the PBS group brains.

3.2. NLRP3 Inflammasome Activation in the Neonatal Period Leads to Behavioral Changes in Early Adulthood

On PND60, the anxiety‐ and depressive‐like behavior of the mice was measured by OFT, TST, and FST. LPS‐injected WT mice spent ∼48% less time in the central zone in the central zone of the open field compared to the PBS group (Figure 2a). They also had significantly lower latency to immobility in TST: the latency when suspended was 101.7 s in the PBS group, whereas it was 80.0 s in the LPS group (Figure 2b). In FST, the latency to immobility was 53.4% shorter in LPS‐injected WT mice compared to the PBS group (Figure 2c).

FIGURE 2.

FIGURE 2

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Neonatal LPS induction results in higher anxiety‐ and depressive‐like behavior in early adulthood. (a) Time spent in the central zone of the open field within 6 min of recording time. (b) Latency to immobility in tail suspension test and (c) forced swim test (n = 5, *p < 0.05). ns, not significant.

3.3. NLRP3 Inflammasome Activation in the Neonatal Period Decreases PNN‐Positive Neurons in Adulthood

To determine changes in PNN+ neurons, PND60 mouse brain sections were stained with WFA for PNNs. Visualization of PNN+ cells in the hippocampus (Figure 3) and cortex (Figure 4) shows that LPS mice have fewer PNN+ cells than PBS mice, indicating that neonatal systemic LPS exposure reduces PNNs in these regions. Hippocampal PNN+ neurons were decreased by 40.3% (Figure 3b), and cortical PNN+ neurons were reduced by 37.8% (Figure 4b) in LPS‐injected WT mice compared to PBS‐injected WT mice. To confirm this effect further, hippocampal sections from the same animals were stained for the common PNN component neurocan, a specific type of chondroitin sulfate proteoglycan. The results showed a similar pattern where the neurocan‐positive cells in the LPS group were reduced by 43.7% compared to the PBS group (Figure S1).

FIGURE 3.

FIGURE 3

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Neonatal LPS induction results in fewer PNN+ neurons in the hippocampus in early adulthood. (a) Representative images of the hippocampal CA3 regions of PND60 mice. (scale bar = 50 µm) (b) Quantification of WFA+ neurons/mm2 in hippocampal sections (n = 5, **p < 0.01). ns, not significant.

FIGURE 4.

FIGURE 4

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Neonatal LPS induction results in fewer PNN+ neurons in the cortex in early adulthood. (a) Representative images of the cortices of PND60 mice. (scale bar = 50 µm) (b) Quantification of WFA+ neurons/mm2 in cortical sections (n = 5, **p < 0.01). ns, not significant.

In order to determine which layers are affected the most by the decrease in PNNs, we also compared between groups the number of PNN+ neurons in each layer. PNNs were heavily concentrated in the pyramidal layer. For WFA‐stained PNNs, significant decreases were confirmed in the stratum oriens (−52.2%) and stratum pyramidale (−50.0%) between PBS‐ and LPS‐injected WT mice. For neurocan staining, PNNs were only significantly reduced in the stratum pyramidale (−41.5%) (Figure S2).

To examine whether the LPS injection resulted in lower neuron numbers, the neurons in the pyramidal layer of the hippocampus and the cortical sections were compared between the PBS and LPS groups. There was no significant difference between neuron densities in these comparisons (Figure S3a,b). There was also no difference between the total areas of the pyramidal layer in images captured for each group (Figure S3c).

Our findings indicate that hippocampal and cortical PNNs in adulthood, as measured by WFA and neurocan, decrease with neonatal LPS‐injection and that this effect is not concomitant with a decrease in neuron numbers.

3.4. The Effect of Neonatal LPS‐Induced Inflammasome Activation on Behavior and PNNs Is NLRP3‐Dependent

As expected, NLRP3 KO mice at PND10 had no NLRP3 protein expression in their brains (Figure 1b,c). Moreover, any significant ASC and IL‐1β increase upon LPS injection was absent in NLRP3KO mice (Figure 1b,d,e). Our results support the conclusion that LPS‐induced neonatal brain immune activation in the form of IL‐1β is NLRP3‐dependent.

The anxiety‐ and depressive‐like behavior seen in LPS‐injected WT mice was not observed in NLRP3‐deficient mice. Both LPS‐ and PBS‐injected groups spent comparable amounts of time in the central zone in OFT (Figure 2a) and exhibited similar latencies to immobility (Figure 2b,c).

Moreover, it was also seen in hippocampal (Figure 3) and cortical (Figure 4) sections of NLRP3‐deficient mice that LPS injections did not result in a significant decrease in PNN+ cells, as observed between LPS‐injected and PBS‐injected WT mice. Similarly, there was no significant decrease in neurocan‐positive cells in the hippocampus between the two different groups of NLRP3‐deficient mice (Figure S1), and none of the hippocampal layers of the NLRP3‐deficient animals had a separate significant change in PNN numbers with LPS injection (Figure S2).

4. Discussion

In our study, we investigated whether cerebral NLRP3 activation in the neonatal period could lead to a change in PNN numbers in adulthood. The immunofluorescence results of our research, where LPS injection leads to reduced PNN numbers and genetically knocking out NLRP3 prevents neurons from losing PNNs, strongly support the idea that NLRP3 is essential in inflammation‐mediated PNN reduction. These findings highlight NLRP3's crucial role in initiating the inflammatory cascade that disrupts PNN integrity, at least in cases of inflammatory insult via LPS or Gram‐negative bacteria.

Our neonatal LPS injection model resulted in increased anxiety‐like and depressive‐like behavior in early adulthood, which is in line with previous studies (Dinel et al. 2014; Liang et al. 2019). Research in rats shows that early‐life (but not neonatal) activation of NLRP3 via LPS or Bisphenol A exposure results in anxiety‐like behavior in adolescence or adulthood (Al‐Shami et al. 2024; Lei, Chen, Yan, Li, and Deng 2017). Another rat study reveals that prenatal bright‐light‐induced stress leads to NLRP3 activation in the frontal cortices of male offspring in adulthood, which is concomitant with depressive‐like behavior (Slusarczyk et al. 2016).

The association between the decrease in PNNs and behavioral changes detected in our study was also observed previously in rats exposed to chronic unpredictable mild stress (Yu et al. 2020). Additionally, it was recently demonstrated that enzymatic digestion of PNNs could directly induce anxiety‐like behavior in mice (Li et al. 2024), indicating that the decrease in PNNs might be linked to the behavioral changes in our model. The effect of early‐life inflammation on PNN numbers has been demonstrated in a previous study where prenatal intravenous polyinosinic‐polycytidylic acid (poly(I:C)) injection resulted in fewer PNNs in the brains of adult offspring (Paylor et al. 2016). Consistent with these findings, our study yielded comparable results using neonatal systemic LPS exposure. Furthermore, we found that the decrease in PNN numbers depended on the activation of the NLRP3 inflammasome.

It is important to note that while our results in mice show a reduction in PNN+ neurons in early adulthood, this does not necessarily imply that the PNNs of neurons have been degraded. This is because both microglia numbers and PNN staining intensity are substantially low during the first week after birth compared to adolescence and adulthood in rodents. Microglia in the hippocampus are nearly absent at birth, rise by PND7, peak at PND14, and then stabilize at about half the peak level in early adulthood (Kim et al. 2015). Similarly, PNN components like aggrecan, brevican, and tenascin‐R are undetectable or significantly low in the first 2 weeks after birth, increasing after PND15 in mice (Miyata and Kitagawa 2016). It was demonstrated in comparable findings in rodents that WFA+ cells in various brain regions begin to appear after PND14 (Paylor et al. 2016; Ye and Miao 2013). The idea that PNN degradation might be absent in the neonatal period is consistent with the previously mentioned rat poly(I:C) study, where offspring exposed to prenatal poly(I:C) injections had significantly fewer PNNs at PND90 compared to offspring exposed to prenatal saline, despite both groups exhibiting similar PNN numbers throughout earlier periods. This implies that rather than causing direct microglia‐mediated degradation, the inflammation at the embryonic stage had a more subtle effect on the capacity of neurons to form PNNs. Corroborating this, the rat study also reports unchanged microglial numbers between the saline and poly(I:C) groups across all ages. Nevertheless, it should be noted that cell density alone does not serve as a sensitive indicator of the full scope of microglial roles in the CNS. Changes in the secretion of extracellular matrix‐degrading enzymes by microglia or increased phagocytic activity in microglia may occur without alterations in the number of microglia. Indeed, NLRP3 inflammasome activation is linked to increased expression of matrix metalloproteinase(MMP)‐9 and MMP‐13 (B. Liu et al. 2023; Ren et al. 2020), which can contribute to PNN degradation (Cheung et al. 2024; Kelly, Russo, Jackson, Lamantia, and Majewska 2015; B. Liu et al. 2023; Murase et al. 2017; Venturino et al. 2021; Wegrzyn et al. 2021). Thus, it is possible that neonatal LPS exposure has both early effects on neuronal proteins involved in PNN formation and also long‐term effects on microglia that promote a phagocytic and PNN‐degrading phenotype.

It is also worth noting the limitations in our study. First, as discussed above, the NLRP3‐dependent mechanism through which PNNs are lost is yet unknown, though it may be associated with MMP release. Second, while we focused on specific regions of the brain in our PNN analysis, inflammasome activation analysis was performed at the whole brain level; meaning that it may not accurately reflect the inflammasome activation in individual regions. Nonetheless, findings in the literature suggest that in models of systemic inflammation via intraperitoneal LPS, the hippocampus undergoes inflammatory changes (like elevated IL‐1β or increased microglial marker staining) similar to other brain regions like the hypothalamus, brainstem, and cortex (Datta and Opp 2008; Qin et al. 2007). This suggests that a change in inflammasome components at the whole brain level would likely reflect parallel changes in the hippocampus and the cortex. A third limitation is the lack of additional time points for PNN analysis: it would be useful to determine more precisely when the difference in PNN numbers between healthy and inflamed brains first appears. A more detailed time course analysis of PNN change across different ages is therefore a potential avenue for future research.

5. Conclusion

In conclusion, our study shows that neonatal NLRP3 inflammasome activation in the brain significantly reduces PNNs in early adulthood. Our findings suggest that in cases of acute neonatal neuroinflammation, drugs that target NLRP3 directly could effectively prevent deleterious changes to PNN development. Thus, inflammatory insults inhibiting the formation or maintenance of PNNs would be mitigated without a large number of side effects.

Author Contributions

Emre Tarakcioglu: Conceptualization, methodology, experimental procedures, analysis, writing – original draft, revisions and editing, visualization. Bilgesu Genc: Experimental procedures, analysis, revisions and editing. Kemal Ugur Tufekci: Conceptualization, methodology, resources, revisions and editing, supervision, funding acquisition. Sermin Genc: Conceptualization, methodology, resources, revisions and editing, supervision. All authors read and approved the final manuscript.

Ethics Statement

The in vivo procedures in this study have been approved by the Izmir International Biomedicine and Genome Institute Local Ethics Committee for Animal Experiments (IBG‐AELEC) with the protocol number 2022‐002.

Conflicts of Interest

The authors declare no conflicts of interest.

Supporting information

Supporting Figures: dneu22986‐sup‐0001‐Figures.pdf

DNEU-85-0-s001.pdf (665.3KB, pdf)

Acknowledgments

This study was funded by the Scientific and Technological Research Council of Turkey (TÜBİTAK) under the 3501 Career Development Program (grant code 321S141). We thank Yusuf Guducu, Batin Gulec, Huseyin Kocakusak, and Burak Ibrahim Arioz for their help with the animal behavioral tests.

Funding: This study was funded by the Türkiye Bilimsel ve Teknolojik Araştırma Kurumu.

Data Availability Statement

The data in the study are available upon request to the corresponding author.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Supporting Figures: dneu22986‐sup‐0001‐Figures.pdf

DNEU-85-0-s001.pdf (665.3KB, pdf)

Data Availability Statement

The data in the study are available upon request to the corresponding author.

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