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Yaseen Awad-Igbaria,1,2 Shilo Dadon,1,2 Alon Shamir,3,4 Alejandro Livoff,5 Mark Shlapobersky,5 Jacob Bornstein,1,2,* Eilam Palzur2,* 1Faculty of Medicine in the Galilee, Bar-Ilan University, Safed, Israel; 2The Research Institute of Galilee Medical Center, Nahariya, Israel; 3Psychobiology Research Laboratory, Mazor Mental Health Center, Akko, Israel; 4The Ruth and Bruce Rappaport Faculty of Medicine, Technion – Israel Institute of Technology, Haifa, Israel; 5Pathology Department, Barzilai University Medical Center, Ashkelon, Israel*These authors contributed equally to this workCorrespondence: Yaseen Awad-Igbaria, The Research Institute of Galilee Medical Center, PO Box 21, Nahariya, 22100, Israel, Tel +972 50-4500101, Email Yaseenawad123@gmail.comBackground: Provoked vulvodynia (PV) is the main cause of vulvar pain and dyspareunia. The etiology of PV has not yet been elucidated. However, PV is associated with a history of recurrent inflammation, and its often accompanied by increases in the numbers of mast cells (MCs) and sensory hyperinnervation in the vulva. Therefore, this study aimed to examine the role of MCs and the early inflammatory events in the development of chronic vulvar pain in a rat model of PV.Methods: Mechanical and thermal vulvar sensitivity was measured for 5 months following zymosan vulvar challenges. Vulvar changes in glutamate and nerve growth factor (NGF) were analyzed using ELISA. Immunofluorescence (IF) staining of the vulvar section after 20, 81, and 160 days of the zymosan challenge were performed to test MCs accumulation, hyperinnervation, and expression of pain channels (transient receptor potential vanilloid/ankyrin-1-TRPV1 & TRPA1) in vulvar neurons. Changes in the development of vulvar pain were evaluated following the administration of the MCs stabilizer ketotifen fumarate (KF) during zymosan vulvar challenges.Results: Zymosan-challenged rats developed significant mechanical and thermal vulvar sensitivity that persisted for over 160 days after the zymosan challenge. During inflammation, increased local concentrations of NGF and glutamate and a robust increase in MCs degranulation were observed in zymosan-challenged rats. In addition, zymosan-challenged rats displayed sensory hyperinnervation and an increase in the expression of TRPV1 and TRPA1. Treatment with KF attenuated the upregulated level of NGF during inflammation, modulated the neuronal modifications, reduced MCs accumulation, and enhanced mechanical hypersensitivity after repeated inflammation challenges.Conclusion: The present findings suggest that vulvar hypersensitivity is mediated by MCs accumulation, nerve growth, and neuromodulation of TRPV1 and TRPA1. Hence, KF treatment during the critical period of inflammation contributes to preventing chronic vulvar pain development.Keywords: provoked vulvodynia, inflammation, mast cell, nerve growth factor, glutamate, hyperinnervation

Maternal obesity in pregnancy and lactation is linked to metabolic disturbances and neurodevelopmental problems in offspring, increasing the risk of psychiatric disorders in adulthood. We proposed that maternal N-acetyl cysteine (NAC) supplementation during lactation, a critical period for neurodevelopment, potentially protects offspring from developing cognitive impairment in adulthood. Fifteen young female ICR mice were randomly allocated to different experimental groups: high-fat diet (HFD; 60.3% fat before mating, during pregnancy and lactation), HFD-NAC of 300 mg/Kg/day during lactation, CD (high-fat diet before mating, during pregnancy, and regular chow control diet of 8.2% fat during lactation), CD-NAC of 300 mg/Kg/day during lactation and control group consuming regular chow diet. The serum inflammatory markers of the offspring were evaluated post-weaning, while metabolic markers, microglial density, and cognitive performance were assessed in adulthood using the novel Object Recognition and Morris Water Maze tests. Our results demonstrate maternal obesity during gestation and lactation increased body weight, hepatic steatosis, and microglial cell density in the dentate gyrus (DG) and cortex. Furthermore, these offspring exhibited reduced spatial learning abilities in adulthood, regardless of sex. However, maternal NAC administration during lactation and maternal diet intervention significantly reduced brain microglial density and improved both male and female offspring metabolic profiles. More importantly, NAC supplementation during lactation, regardless of maternal diet, enhanced male offspring's learning ability in adulthood. Our findings indicate that administering NAC to obese mothers during the critical lactation period may offer protection against metabolic disturbances and cognitive deficits in adult offspring previously exposed to maternal obesity., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2025. Published by Elsevier Ltd.)

Neuropathic pain remains one of the leading causes of global disability. The mechanism of neuropathic pain development and maintenance involves mitochondrial dysfunction induced-neuronal apoptosis of peripheral and central nociceptive pathways. The TRPV1 is a non-selective cation channel, which has a high Ca2+ permeability, playing an essential role in neuronal apoptosis in the spinal cord following peripheral nerve injury. However, the mechanism of how TRPV1 activation in the spinal cord induces mitochondrial dysfunction-mediate neuronal apoptosis, resulting in allodynia is unknown. Here, we found that activating the TRPV1 channel in the spinal cord using capsaicin, a TRPV1 agonist, results in mechanical and thermal hypersensitivity that were found to be mediated by neuroinflammation, elevated level of apoptosis, and a reduction in transcription of the mitochondrial complexes in the spinal cord and DRG. Moreover, during the early activation of the TRPV1 (1h, 24h, 48h following the capsaicin injection in the spinal cord) we observed a robust reduction in mitochondrial oxygen consumption in the non-phosphorylated state, ATP-linked respiration, maximal respiration, and electron transfer capacity (ETC). A more advanced experiment, wherein we controlled capsaicin, Ca2+ concentration and the exposure time in isolated spinal cord tissue (Lumbar, L1-L6), unveiled that TRPV1 activation impairing the mitochondrial function in terms of oxygen consumption, collapsing the Ψm and induction of the mitochondrial permeability transition pore (mPTP), which were reversed by the mPTP inhibitor-Cyclosporin A (CsA) during challenging the mitochondria with Ca2+ in a dose-dependent manner. More critically, injection of TRPV1 antagonist AMG9810 in the spinal cord following sciatic nerve crush reversed mechanical allodynia and modulated thermal hypersensitivity. In addition, the presence of TRPV1 antagonist-AMG9810 along with capsaicin and Ca2+ during challenging the spinal cord tissue completely prevents the early mPTP induction, the reduction in oxygen consumption and. In conclusion, our findings suggest that TRPV1 activation induces neuronal apoptosis, neuroinflammation, and mitochondrial dysfunction in the spinal cord, reflected in mechanical and thermal allodynia. Notable, the mitochondrial dysfunction following the TRPV1 activation in the spinal cord includes crucial elements that contribute to neuronal death, including mPTP induction, reduction in Ψm and oxygen consumption. Strikingly, regulating the TRPV1 following sciatic nerve injury reverses hypersensitivity probably via protection of the mitochondrial, suggesting a fundamental role for the TRPV1 pathway in mitochondrial dysfunction-mediated pain development., (© The Author(s) 2025. Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Provoked vulvodynia (PV) is the leading cause of vulvar pain and dyspareunia. The etiology of PV is multifactorial and remains poorly understood. PV is associated with a history of repeated vulvar inflammation and is often accompanied by sensory neuromodulation as a result of activation of the metabotropic glutamate receptor 5 (mGluR5) in the sensory nerve terminals. Therefore, this study aims to examine the role of glutamate-mGluR5 signaling during the initial inflammatory phase in chronic vulvar pain development in an animal model of PV.Thermal and mechanical vulvar sensitivity was assessed for three weeks following zymosan vulvar challenges. Anxiety-like behavior and locomotor activity were assessed at the end of the experiment. To investigate the role of glutamate mGluR5, the MTEP (mGluR5 antagonist) was injected into the vulva during vulvar inflammation. On the other hand, glutamate or CHPG (mGluR5 agonist) were injected in order to examine the effects of mGluR5 activation. RT-PCR was performed to assess changes in the transcription of genes related to neuroinflammation, neuromodulation, and neuroplasticity in the spinal cord (L6-S3). Zymosan-induced inflammation resulted in a significant thermal and mechanical vulvar hypersensitivity that persisted for over a month after the zymosan injection. However, local treatment with MTEP enhanced the vulvar mechanical and thermal hypersensitivity. On the other hand, activation of the mGluR5 via injection of glutamate or CHPG into the vulva leads to long-lasting vulvar mechanical and thermal hypersensitivity. The activation of the glutamate pathway was found to be accompanied by an increase in the transcription level of genes related to neuroinflammation and neuroplasticity in the sacral spine region. The present findings indicate that vulvar hypersensitivity is mediated by mGluR5 activation during inflammation. Hence, modulation of the mGluR5 pathway during the critical period of inflammation contributes to preventing chronic vulvar pain development. Conversely, activation of the mGluR5 pathway leads to long-lasting mechanical and thermal hypersensitivity.

Provoked vulvodynia (PV) is characterized by localized chronic vulvar pain. It is associated with a history of recurrent inflammation, mast cell (MC) accumulation and neuronal sprouting in the vulva. However, the mechanism of how vulvar-inflammation promotes neuronal sprouting and gene-expression adaptation in the spinal cord, leading to hypersensitivity and painful sensations, is unknown. Here, we found that vulvar tissue from women with PV (n = 8) is characterized by MC accumulation and neuronal sprouting compared to women without PV (n = 4). In addition, we observed these changes in an animal study of PV. Thus, we found that repeated vulvar zymosan-inflammation challenges lead to long-lasting mechanical and thermal vulvar hypersensitivity, which is mediated by MC accumulation, neuronal sprouting, overexpression of the pain channels (TRPV1 and TRPA1) in vulvar neurons, as well as a long-term increase of gene expression related to neuroplasticity, neuroinflammation and nerve growth factor (NGF) in the spinal cord/dorsal root ganglia (DRG) (L6-S3). However, regulation of the NGF pathway by stabilization of MC activity with ketotifen fumarate (KF) during vulvar inflammation attenuates the local increase of NGF and histamine, as well as the elevated transcription of pro-inflammatory cytokines and NGF pathway in the spinal cord. Additionally, KF treatment during inflammation modulates MC accumulation, neuronal hyperinnervation and overexpression of the TRPV1 and TRPA1 channels in the vulvar neurons, consequently preventing the development of vulvar pain. A thorough examination of the NGF pathway during inflammation revealed that blocking NGF activity by using an NGF-non-peptide-inhibitor (Ro08-2750) regulates the upregulation of genes related to neuroplasticity and the NGF pathway in the spinal cord, as well as modulating neuronal sprouting and overexpression of the pain channels, resulting in a reduced level of vulvar hypersensitivity. On the other hand, stimulation of the NGF pathway in the vulvar promotes neuronal sprouting, overexpression of pain channels and increase of gene expression related to neuroplasticity, neuroinflammation and NGF in the spinal cord, resulting in long-lasting vulvar hypersensitivity. In conclusion, our findings suggest that vulvar allodynia induced by inflammation is mediated by MC accumulation, neuronal sprouting and neuromodulation in the vulvar. Additionally, chronic vulvar pain may involve a long-term adaptation in gene expression in the spinal cord, which probably plays a critical role in central sensitization and pain maintenance. Strikingly, regulating the NGF pathway during the critical period of inflammation prevents vulvar pain development via modulating the neuronal changes in the vestibule and spinal cord, suggesting a fundamental role for the NGF pathway in PV development., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Introduction: Hyperbaric oxygen has been used as a medical treatment tool in hyperbaric chambers and is an integral part of professional and combat divers' activity. In extreme cases, exposure to hyperbaric oxygen can develop central nervous system oxygen toxicity (CNS-OT), which leads to seizures and eventually death. CNS-OT is caused by neuronal hyperactivity due to high oxygen levels, potentially damaging brain cells including the blood-brain barrier (BBB). However, the effect of hyperbaric oxygen levels on the healthy BBB has not been characterized directly yet., Methods: Six or three different groups of ~ eight rats or mice, respectively, were exposed to increasing levels of partial pressure of oxygen (0.21 to 5 ATA) in a hyperbaric chamber, followed by MRI scanning with gadolinium. Statistical significance (adjusted p-value ≤ 0.05) was assessed using linear regression and ordinary one-way (rats) or two-way (mice) ANOVA with correction of multiple comparison tests. In rats, the effect of 100% oxygen at 5 ATA was independently validated using FITC-Dextran (5 kDa). Statistical significance (p-value ≤ 0.05) was assessed using Welch's t-test and effect size was calculated by Cohen's D., Results: In rats, analyzed MRI scans showed a significant trend of increase in the % gadolinium in brain tissues as a result of hyperbaric oxygen pressures (p-value = 0.0079). The most significant increase was measured at 4 ATA compared to air (adjusted p-value = 0.0461). Significant increased FITC-Dextran levels were measured in the rats' brains under 100% oxygen at 5 ATA versus air (p-value = 0.0327; Effect size = 2.0). In mice, a significant increase in gadolinium penetration into the hippocampus and frontal cortex was measured over time (adjusted p-value < 0.05) under 100% oxygen at 3 and 5 ATA versus air, and between the treatments (adjusted p-value < 0.0001)., Conclusions: The BBB is increasingly disrupted due to higher levels of hyperbaric oxygen in rodents, indicating a direct relation between hyperbaric oxygen and BBB dysregulation for the first time. We suggest considering this risk in different diving activities, and protocols using a hyperbaric chamber. On the other hand, this study highlights the potential therapeutic usage of hyperbaric oxygen for controlled drug delivery through the BBB into brain tissues in different brain-related diseases., (© 2024. The Author(s).)

Provoked vulvodynia represents a challenging chronic pain condition, characterized by its multifactorial origins. The inherent complexities of human-based studies have necessitated the use of animal models to enrich our understanding of vulvodynia's pathophysiology. This review aims to provide an exhaustive examination of the various animal models employed in this research domain. A comprehensive search was conducted on PubMed, utilizing keywords such as "vulvodynia", "chronic vulvar pain", "vulvodynia induction", and "animal models of vulvodynia" to identify pertinent studies. The search yielded three primary animal models for vulvodynia: inflammation-induced, allergy-induced, and hormone-induced. Additionally, six agents capable of triggering the condition through diverse pathways were identified, including factors contributing to hyperinnervation, mast cell proliferation, involvement of other immune cells, inflammatory cytokines, and neurotransmitters. This review systematically outlines the various animal models developed to study the pathogenesis of provoked vulvodynia. Understanding these models is crucial for the exploration of preventative measures, the development of novel treatments, and the overall advancement of research within the field.

The etiology of idiopathic pain conditions, such as Provoked vulvodynia (PV), is multifactorial. The efficiency of venlafaxine, serotonin-noradrenaline reuptake inhibitor (SNRIs) in modulating vulvar pain led to the hypothesis that PV might involve central mechanisms. Here, we investigate whether vulvar pain is associated with gene-expression changes in mood, stress and pain systems, including amygdala (Amg), medial prefrontal cortex (mPFC), and periaqueductal gray matter (PAG). Additionally, we examined the analgesic and anxiolytic effects of venlafaxine. We found that the development of chronic vulvar pain in an animal model of PV is associated by overexpression of genes related to neuronal-activity and neuroinflammation in the Amg, mPFC, and PAG. Additionally, changes in the expression of GABA and serotonin synthesis, and reuptake were noted in the Amg and mPFC. Unsurprisingly, anxiety-like behavior and emotional-disorder were observed in rats with chronic vulvar pain. Nevertheless, treatment with venlafaxine (37.5 mg/kg) for one month significantly improves the vulvar hypersensitivity, as well as reduces the anxiety level. More critically, the long-term gene expression adaptation in serotonin receptor and synthesis, GABA synthesis, neuroplasticity, and neuroinflammation in the Amg, mPFC, and PAG, were modulated by venlafaxine in rats with vulvar pain. Our findings suggest that vulvar hypersensitivity induced by inflammation might associated with gene expression changes in brain areas that are involved in mood, stress and pain regulation. These changes probably play a role in central sensitization, and anxiety. Strikingly, enhancing the activity of serotonin and noradrenaline via venlafaxine treatment in rats with vulvar pain induces analgesic and anxiolytic effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Introduction: Vulvodynia is defined as vulvar pain of at least 3 months' duration, without clear identifiable cause, which may have potential associated factors. It can have a significant impact on women's quality of life due to a combination of physical pain, emotional distress, and limited treatment options. Despite affecting a considerable number of women worldwide, the causes and underlying mechanisms of vulvodynia remain poorly understood. Given the recognized association of the vaginal microbiota with various gynecologic disorders, there has been growing interest in exploring the potential role of the vaginal microbiota in the etiology of vulvodynia. This systematic review aims to evaluate the current literature on the association between the vaginal microbiota and vulvodynia., Material and Methods: A systematic search of multiple databases, including PubMed, Scopus, Web of Science, Cochrane Library, and Ovid MEDLINE, was conducted to identify relevant peer-reviewed studies up to May 12, 2023. The following search terms were used across these databases: "vulvodynia," "vestibulodynia," "vulvar vestibulitis," "microbiome," "microbiota," and "flora.", Results: A total of 8 case-control studies were included, the quality of which was assessed using the Newcastle-Ottawa Scale. Data extraction and synthesis were performed using a standardized protocol. In most studies, no major differences were found between the vaginal bacterial composition of women with vulvodynia and that of controls. No specific bacterial taxa were consistently associated with vulvodynia. The relationship between vaginal microbiota diversity and vulvodynia remains to be fully understood., Conclusions: The role of vaginal microbiota in vulvodynia, if any, remains unclear. Because of the cross-sectional nature of the included studies, it is not possible to make any causal inferences. Further research, using larger and more diverse study populations and advanced sequencing techniques, is necessary to gain a better understanding of the potential relationship between the vaginal microbiota and vulvodynia., Competing Interests: The authors have declared they have no conflicts of interest., (Copyright © 2023, ASCCP.)

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality in young adults, characterized by primary and secondary injury. Primary injury is the immediate mechanical damage, while secondary injury results from delayed neuronal death, often linked to mitochondrial damage accumulation. Hyperbaric oxygen therapy (HBOT) has been proposed as a potential treatment for modulating secondary post-traumatic neuronal death. However, the specific molecular mechanism by which HBOT modulates secondary brain damage through mitochondrial protection remains unclear. Spatial learning, reference memory, and motor performance were measured in rats before and after Controlled Cortical Impact (CCI) injury. The HBOT (2.5 ATA) was performed 4 h following the CCI and twice daily (12 h intervals) for four consecutive days. Mitochondrial functions were assessed via high-resolution respirometry on day 5 following CCI. Moreover, IHC was performed at the end of the experiment to evaluate cortical apoptosis, neuronal survival, and glial activation. The current result indicates that HBOT exhibits a multi-level neuroprotective effect. Thus, we found that HBOT prevents cortical neuronal loss, reduces the apoptosis marker (cleaved-Caspase3), and modulates glial cell proliferation. Furthermore, HBO treatment prevents the reduction in mitochondrial respiration, including non-phosphorylation state, oxidative phosphorylation, and electron transfer capacity. Additionally, a superior motor and spatial learning performance level was observed in the CCI group treated with HBO compared to the CCI group. In conclusion, our findings demonstrate that HBOT during the critical period following the TBI improves cognitive and motor damage via regulating glial proliferation apoptosis and protecting mitochondrial function, consequently preventing cortex neuronal loss.

Stress is becoming increasingly commonplace in modern times, making it important to have accurate and effective detection methods. Currently, detection methods such as self-evaluation and clinical questionnaires are subjective and unsuitable for long-term monitoring. There have been significant studies into biomarkers such as HRV, cortisol, electrocardiography, and blood biomarkers, but the use of multiple electrodes for electrocardiography or blood tests is impractical for real-time stress monitoring. To this end, there is a need for non-invasive sensors to monitor stress in real time. This study looks at the possibility of using breath and skin VOC fingerprinting as stress biomarkers. The Trier social stress test (TSST) was used to induce acute stress and HRV, cortisol, and anxiety levels were measured before, during, and after the test. GC-MS and sensor array were used to collect and measure VOCs. A prediction model found eight different stress-related VOCs with an accuracy of up to 78%, and a molecularly capped gold nanoparticle-based sensor revealed a significant difference in breath VOC fingerprints between the two groups. These stress-related VOCs either changed or returned to baseline after the stress induction, suggesting different metabolic pathways at different times. A correlation analysis revealed an association between VOCs and cortisol levels and a weak correlation with either HRV or anxiety levels, suggesting that VOCs may include complementary information in stress detection. This study shows the potential of VOCs as stress biomarkers, paving the way into developing a real-time, objective, non-invasive stress detection tool for well-being and early detection of stress-related diseases.

Background: Peripheral nerve injury can cause neuroinflammation and neuromodulation that lead to mitochondrial dysfunction and neuronal apoptosis in the dorsal root ganglion (DRG) and spinal cord, contributing to neuropathic pain and motor dysfunction. Hyperbaric oxygen therapy (HBOT) has been suggested as a potential therapeutic tool for neuropathic pain and nerve injury. However, the specific cellular and molecular mechanism by which HBOT modulates the development of neuropathic pain and motor dysfunction through mitochondrial protection is still unclear., Methods: Mechanical and thermal allodynia and motor function were measured in rats following sciatic nerve crush (SNC). The HBO treatment (2.5 ATA) was performed 4 h after SNC and twice daily (12 h intervals) for seven consecutive days. To assess mitochondrial function in the spinal cord (L2-L6), high-resolution respirometry was measured on day 7 using the OROBOROS-O2k. In addition, RT-PCR and Immunohistochemistry were performed at the end of the experiment to assess neuroinflammation, neuromodulation, and apoptosis in the DRG (L3-L6) and spinal cord (L2-L6)., Results: HBOT during the early phase of the SNC alleviates mechanical and thermal hypersensitivity and motor dysfunction. Moreover, HBOT modulates neuroinflammation, neuromodulation, mitochondrial stress, and apoptosis in the DRG and spinal cord. Thus, we found a significant reduction in the presence of macrophages/microglia and MMP-9 expression, as well as the transcription of pro-inflammatory cytokines (TNFa, IL-6, IL-1b) in the DRG and (IL6) in the spinal cord of the SNC group that was treated with HBOT compared to the untreated group. Notable, the overexpression of the TRPV1 channel, which has a high Ca 2+ permeability, was reduced along with the apoptosis marker (cleaved-Caspase3) and mitochondrial stress marker (TSPO) in the DRG and spinal cord of the HBOT group. Additionally, HBOT prevents the reduction in mitochondrial respiration, including non-phosphorylation state, ATP-linked respiration, and maximal mitochondrial respiration in the spinal cord after SNC., Conclusion: Mitochondrial dysfunction in peripheral neuropathic pain was found to be mediated by neuroinflammation and neuromodulation. Strikingly, our findings indicate that HBOT during the critical period of the nerve injury modulates the transition from acute to chronic pain via reducing neuroinflammation and protecting mitochondrial function, consequently preventing neuronal apoptosis in the DRG and spinal cord., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Stress is a leading cause of several disease types, yet it is underdiagnosed as current diagnostic methods are mainly based on self-reporting and interviews that are highly subjective, inaccurate, and unsuitable for monitoring. Although some physiological measurements exist ( e.g ., heart rate variability and cortisol), there are no reliable biological tests that quantify the amount of stress and monitor it in real time. In this article, we report a novel way to measure stress quickly, noninvasively, and accurately. The overall detection approach is based on measuring volatile organic compounds (VOCs) emitted from the skin in response to stress. Sprague Dawley male rats ( n = 16) were exposed to underwater trauma. Sixteen naive rats served as a control group ( n = 16). VOCs were measured before, during, and after induction of the traumatic event, by gas chromatography linked with mass spectrometry determination and quantification, and an artificially intelligent nanoarray for easy, inexpensive, and portable sensing of the VOCs. An elevated plus maze during and after the induction of stress was used to evaluate the stress response of the rats, and machine learning was used for the development and validation of a computational stress model at each time point. A logistic model classifier with stepwise selection yielded a 66-88% accuracy in detecting stress with a single VOC (2-hydroxy-2-methyl-propanoic acid), and an SVM (support vector machine) model showed a 66-72% accuracy in detecting stress with the artificially intelligent nanoarray. The current study highlights the potential of VOCs as a noninvasive, automatic, and real-time stress predictor for mental health.

The effects of MgSO 4 as an anti-inflammatory agent in pregnant women have been investigated in the last few years. Infections can cause an inflammatory reaction involving the placenta membranes and amniotic cavity. They may have short-term effects on the mother and her fetuses, like preterm birth, cerebral palsy, and developmental delay. Despite the alleged advantages of MgSO 4 as a neuroprotective agent in the preterm brain, the long-term molecular and behavioral function of MgSO 4 has not been fully elucidated. Here, we investigated the long-term effect of antenatal MgSO 4 , during late gestation, on offspring's behavior focusing on cognitive function, motor activity, and social cognition in adolescence and adulthood, and explored its influence on brain gene expression (e.g., ErbB signaling, pro-inflammatory, and dopaminergic markers) in adulthood. A significant abnormal exploratory behavior of offspring of MgSO 4 -treated dams was found compared to the control group in both adolescence and adulthood. Furthermore, we found that adult females exposed to MgSO 4 under inflammation displayed working and recognition memory impairment. A reduction in IL-6 expression was detected in the prefrontal cortex, and hippocampus specimens derived from LPS-Mg-treated group. In contrast, an imbalanced expression of dopamine 1 and 2 receptors was detected only in prefrontal cortex specimens. Besides, we found that MgSO 4 ameliorated the overexpression of the Nrg1 and Erbb4 receptors induced by LPS in the hippocampus. Thus, MgSO 4 treatment for preventing brain injuries can adversely affect offspring cognition behavior later in life, depending on the sex and age of the offspring., (© 2022 The Authors. Journal of Neuroscience Research published by Wiley Periodicals LLC.)

Background: Substantial evidence suggests that hypertension is a significant risk factor for cognitive decline. However, it is unclear whether the genetic predisposition to hypertension is also associated with cellular dysfunction that promotes neurodegeneration., Methods: Changes in blood pressure were evaluated following dietary salt-loading or administration of a regular diet in Sabra Normotensive (SBN/y) and Sabra Hypertension-prone rats (SBH/y). We performed quantitative RT-PCR and immunofluorescence staining in brain cortical tissues before salt loading and 6 and 9 months after salt loading. To examine the expression of brain cortical proteins involved in the gene regulation (Histone Deacetylase-HDAC2; Histone Acetyltransferase 1-HAT1), stress response (Activating Transcription Factor 4-ATF4; Eukaryotic Initiation Factor 2- eIF2α), autophagy (Autophagy related 4A cysteine peptidase- Atg4a; light-chain 3-LC3A/B; mammalian target of rapamycin complex 1- mTORC1) and apoptosis (caspase-3)., Results: Prior to salt loading, SBH/y compared to SBN/y expressed a significantly higher level of cortical HAT1 (protein), Caspase-3 (mRNA/protein), LC3A, and ATF4 (mRNA), lower levels of ATG4A (mRNA/protein), LC3A/B, HDAC2 (protein), as well as a lower density of cortical neurons. Following dietary salt loading, SBH/y but not SBN/y developed high blood pressure. In hypertensive SBH/y, there was significant upregulation of cortical HAT1 (protein), Caspase-3 (protein), and eIF2α ~ P (protein) and downregulation of HDAC2 (protein) and mTORC1 (mRNA), and cortical neuronal loss., Conclusions: The present findings suggest that genetic predisposition to hypertension is associated in the brain cortex with disruption in autophagy, gene regulation, an abnormal response to cellular stress, and a high level of cortical apoptosis, and could therefore exacerbate cellular dysfunction and thereby promote neurodegeneration., (© 2023. The Author(s).)

Epidemiological and experimental evidence demonstrates that maternal exposure to infection during gestation increases the offspring's risk of developing schizophrenia and other neurodevelopmental disorders. In addition, the NRG-ErbB4 signaling pathway is involved in brain development and neuropsychiatric disorders. Specifically, this pathway modulates the dopaminergic and GABAergic systems and is expressed in the early stages of prenatal development. We recently demonstrated that maternal immune activation (MIA) at late gestation altered the expression of NRG1, its receptor ErbB4, and the dopamine D2 receptor four hours post-injection of viral or LPS in the fetal brain. We also reported that blocking the ErbB pathway during adolescence resulted in increased striatal DA content and reduced preference for sweetness and alcohol that persists into adulthood. However, the combined effects of MIA, re-activation of the immune system, and disruption of the ErbB signaling during adolescence would affect young adult mice's behavioral phenotype is unknown. Here, we report that the expression levels of the NRG1, ErbB4, GAD 67 , and BDNF were changed as responses to MIA and blocked the ErbB signaling in the frontal cortex of adolescent mice. MIA-Offspring during late gestation and immune system re-activation during adolescence spent less time in the open arms of the elevated plus-maze in adulthood. At the same time, MIA-offspring administrated with the pan-ErbB inhibitor during adolescence spent the same amount of time in the opened arm as the control mice. Combining the ErbB signaling disruption during adolescence leads to a social interaction impairment in female offspring, but not male, without affecting the offspring's motor activity, long-term recognition, and working memory. These results imply that blocking the ErbB signaling during adolescence prevents the development of anxiety-like behavior of the MIA offspring later in life and suggest that this interaction does not reduce the risk of female MIA offspring developing impaired social behavior., (Copyright © 2022 Elsevier Inc. All rights reserved.)

This short opinion aimed to present the evidence to support our hypothesis that vulvodynia is a neuroinflammatory pain syndrome originating in the pelvic visceral nerve plexuses caused by the failure of weakened uterosacral ligaments (USLs) to support the pelvic visceral nerve plexuses, i.e., T11-L2 sympathetic and S2-4 parasympathetic plexuses. These are supported by the USLs, 2 cm from their insertion to the cervix. They innervate the pelvic organs, glands, and muscles. If the USLs are weak or lax, gravitational force or even the muscles may distort and stimulate the unsupported plexuses. Inappropriate afferent signals could then be interpreted as originating from an end-organ site. Activation of sensory visceral nerves causes a neuro-inflammatory response in the affected tissues, leading to neuroproliferation of small peripheral sensory nerve fibers, which may cause hyperalgesia and allodynia in the territory of the damaged innervation. Repair of the primary abnormality of USL laxity, responsible for mechanical stimulation of the pelvic sensory plexus, may lead to resolution of the pain syndrome., (© 2022. The Author(s).)

Objective: The etiology of localized provoked vulvodynia (LPV) remains unknown, but observations suggest the involvement of the vaginal microbiota. We examined the vaginal microbiota of women with LPV and healthy controls, upon after a low-oxalate diet (LOD)., Materials and Methods: A total of 9 women diagnosed with secondary LPV and 21 healthy controls were recruited from the Galilee Medical Center in Israel and subjected to prospective evaluations of their vaginal microbiota. Total DNA was extracted from vaginal discharge samples provided before and after following LOD for 3 weeks and was then subjected to 16S sequencing. Data obtained were then used to evaluate α and β diversity, identify differentially abundant bacterial taxa in LPV, and determine their impact on the metabolism., Results: These evaluations revealed decreased diversity in the vaginal microbiota of women with LPV and identified the Ochrobactrum genus and Pseudomonadaceae family as indicators for LPV. In addition, we identified 23 differentially expressed bacterial metabolic pathways between the LPV and control samples and revealed that LOD could induce changes in the β diversity of LPV vaginal microbiomes, which was further supported by some degree of pain reduction in patients., Conclusions: Localized provoked vulvodynia and LOD were associated with shifts in the vaginal microbiota. However, the impact of these changes on the development of LPV requires additional studies with a larger cohort., Competing Interests: The authors have declared they have no conflicts of interest., (Copyright © 2022, ASCCP.)

The physiological pattern of hormonal and signaling molecules associated with labor induction is not fully clear. We conducted a preliminary study in order to investigate hormonal changes during labor induction in women with previous cesarean section. Eighty-seven women at term, with previous cesarean section, were randomized to undergo induction of labor by breast stimulation or intracervical balloon and compared with spontaneous labor (controls). Maternal serum levels of oxytocin, prostaglandin F2α, prostaglandin E2, prolactin, estradiol, and cortisol were analyzed at 0, 3, and 6 h post-induction initiation. Fetal umbilical cord hormones were measured. No significant difference was found in the induction-to-delivery time or mode of delivery between the induction groups. Maternal serum oxytocin levels decreased to a lesser extent in the breast stimulation group vs. the control group (p=0.003, p<0.001). In the breast stimulation and control groups, prostaglandin E 2 levels increased as labor progressed (p=0.005, 0.002, respectively). Prostaglandin F2α levels decreased over time in the balloon group (p=0.039), but increased in the control group (p=0.037). Both induction methods had similar outcomes. The hormonal studies ascertained the hypothesized mechanisms, with oxytocin level higher during breast stimulation and lower in balloon induction. These observations could help clinicians determine the appropriate method for cervical ripening in women with previous cesarean section. Larger future studies are needed to examine the effect of these hormonal trends on the rate of successful labor induction and complications, such as uterine rupture, in women with previous uterine scars. ClinicalTrials.gov Identifier NCT04244747., (© 2021. Society for Reproductive Investigation.)

The opening of the mitochondrial permeability transition pore (mPTP) has emerged as a pivotal event following traumatic brain injury (TBI). Evidence showing the impact of the translocator protein (TSPO) over mPTP activity has prompted several studies exploring the effect of TSPO ligands, including etifoxine, on the outcome of traumatic brain injury (TBI). Mitochondrial respiration was assessed by respirometry in isolated rat brain mitochondria (RBM) by measurements of oxidative phosphorylation capacity (OXPHOS). The addition of calcium to RBM was used to induce mitochondrial injury and resulted in significant OXPHOS reduction that could be reversed by preincubation of RBM with etifoxine. Sensorimotor and cognitive functions were assessed following controlled cortical impact and compared in vehicle and etifoxine-treated animals. There was no difference between the vehicle and etifoxine groups for sensorimotor functions as assessed by rotarod. In contrast, etifoxine resulted in a significant improvement of cognitive functions expressed by faster recovery in Morris water maze testing. The present findings show a significant neuroprotective effect of etifoxine in TBI through restoration of oxidative phosphorylation capacity associated with improved behavioral and cognitive outcomes. Since etifoxine is a registered drug used in common clinical practice, implementation in a phase II study may represent a reasonable step forward.

Background: Serum biochemical changes during laparoscopic surgery and positive pressure pneumoperitoneum (PP) may reflect mild oxidative stress due to the ischemia-reperfusion (I/R) mechanism. However, there is still a controversy regarding the exact mechanism of PP in creating oxidative stress and whether the induction of PP causes I/R effects at all. To elucidate this debated issue, we studied, for the first time, the changes of I/R parameters in the serum, in a pilot study, during laparoscopic cholecystectomy using a reliable, independent exogenous oxidative biomarker, together with common intrinsic biomarkers of oxidative stress., Patients and Methods: Our study included 20 patients scheduled for elective laparoscopic cholecystectomy. We evaluated the levels of the extrinsic and endogenous markers for oxidative stress during awareness, under anesthesia, the end of surgery (abdominal CO2 evacuation), and 2 h afterward., Results: After an initial increase in oxidative stress following anesthesia, we did not notice any further significant rise in the levels of the synthetic exogenous and the endogenous biomarkers at the end of the surgery and 2 h later on. However, a positive correlation was noted between the levels of both the intrinsic and extrinsic markers., Conclusions: In our study, the capability of the extrinsic biomarker to detect mild oxidative stress was not validated. Our study stresses the heterogeneous nature of the oxidative reactions and the diversity of the endogenous and exogenous biomarkers while detecting various biochemical patterns under mild oxidative stress, during the short period of laparoscopic surgery., (© 2021. The Author(s).)

The classic bone tissue engineering model for bone regeneration combines three elements: scaffolds, biomaterials, and mesenchymal stem cells (MSCs). Incorporation of MSCs and growth factors into a scaffold implanted into the area of bone injury is a proven strategy to achieve successful bone regeneration as demonstrated in the literature. However, a major limitation of using bone grafts or scaffolds is oxygen (O 2 ) deprivation in the inner sections of the construct, due to lack of adequate vascularization. To address this limitation, we proposed two treatment strategies for MSC-seeded constructs or adipose tissue scaffolds before implantation: (1) O 2 enrichment and (2) acclimation to hypoxia. Based on previous studies, the significance of the different O 2 concentrations on MSC biological characteristics remains controversial. Therefore, the optimal O 2 condition for engineered bone tissues should be determined. Thus, we designed an innovative multichamber gas system aimed to simultaneously assess the effects of different O 2 levels on cell culture. This system was assembled using three isolated chambers integrated into a single incubator. To explore the efficacy of our method, we investigated the effect of hyperoxia, normoxia, and hypoxia, (50-60%, 21%, and 5-7.5% O 2 , respectively) on the biological characteristics of human adipose-derived MSCs: immunophenotyping, adhesion, proliferation, and osteogenic, and angiogenic differentiation. Our findings demonstrated that hypoxic adipose-derived mesenchymal stem cells (ASCs) conditions exhibited significantly lower levels of CD34 ( p  = 0.014), with significantly higher osteogenic and angiogenic differentiation capacities ( p  = 0.023 and p  = 0.0042, respectively) than normoxia. Conversely, hyperoxia-cultured ASCs demonstrated significantly higher levels of CD73 and CD90 expression than both normoxic ASCs ( p  = 0.006 and p  = 0.025, respectively) and hypoxic ASCs ( p  = 0.003 and p  = 0.003, respectively). In addition, hyperoxic ASCs showed significantly reduced proliferation capacity by day 11 ( p  = 0.032) and significantly enhanced migration rates after 48 h ( p  = 0.044). The newly developed controllable multichamber gas system was cost-effective and easy to use. Different assays can be performed concurrently while preserving all other conditions identical, and the use of other ranges of O 2 concentrations is feasible and also necessary to determine the ideal O 2 concentration. Furthermore, the multichamber gas system has the potential for wide application, including other cell cultures, grafts, or scaffolds for in vitro and in vivo experimentation. This study was approved by the Galilee Medical Center Helsinki Committee (No. 0009-19-NHR). Impact statement The introduced multichamber gas system provides a custom-made setup for simultaneous control of three oxygen (O 2 ) levels in a single incubator. The use of our innovative multichamber gas system is essential to determine the ideal O 2 levels for engineered tissues by examining multiple O 2 concentrations on cells in vitro . The determined ideal O 2 concentration will then be used through this system to investigate the engrafted cell survival ex vivo , to ensure successful integration of the engineered tissues and tissue regeneration in vivo . Use of this method may promote a therapeutic tool for a major limitation in tissue engineering due to the problematic O 2 insufficiency in tissue scaffolds.

Experimental studies have shown that ligands of the 18 kDa translocator protein can reduce neuronal damage induced by traumatic brain injury by protecting mitochondria and preventing metabolic crisis. Etifoxine, an anxiolytic drug and 18 kDa translocator protein ligand, has shown beneficial effects in the models of peripheral nerve neuropathy. The present study investigates the potential effect of etifoxine as a neuroprotective agent in traumatic brain injury (TBI). For this purpose, the effect of etifoxine on lesion volume and modified neurological severity score at 4 weeks was tested in Sprague-Dawley adult male rats submitted to cortical impact contusion. Effects of etifoxine treatment on neuronal survival and apoptosis were also assessed by immune stains in the perilesional area. Etifoxine induced a significant reduction in the lesion volume compared to nontreated animals in a dose-dependent fashion with a similar effect on neurological outcome at four weeks that correlated with enhanced neuron survival and reduced apoptotic activity. These results are consistent with the neuroprotective effect of etifoxine in TBI that may justify further translational research.

Introduction: Traumatic brain injuries (TBI) are a major cause of mortality and disability among young adults. TBI are characterized by primary injury, the result of a mechanical impact to the cranium and a secondary injury, a series of molecular mechanism processes developing thereafter. Cerebral cells modify their gene and protein expression as a result of the injury. Epigenetic modifications have a key role as regulators of gene transcription and may simultaneously be involved in the regulation of the molecular pathways following TBI. However, the mechanisms are unknown., Objectives: To clarify whether modification in the expression of Histone Acetyl Transferase1 (HAT1) and Histone deacetylase2 (HDAC 2) occurs during secondary brain damage., Methods: Rat diffused head injury model was used; 72 hours post injury animals were sacrificed and the brains were removed for immunohistochemistry staining with Caspase 3, HAT1 and HDAC2 antibodies. We compared these stains in the perilesional versus the contralateral cortex., Results: An increase of Caspase 3 stained cells were observed in the perilesional cortex. HAT1 expression was elevated and HDAC2 expression reduced in the injured cortex., Conclusions: TBI induced modifications in the expression of epigenetic factors were concomitant with increases in apoptotic cell death. The mitochondria involved in the apoptotic processes is a target for epigenetic regulation and also influences it at the same time., Discussion: This study contributes to the understanding of epigenetic modification following TBI. Further study on the relationship between mitochondrial activity and epigenetic regulation has to be performed in order to develop novel drugs and therapies for TBI.

Cerebral edema represents a major threat following traumatic brain injury. However, therapeutic measures for control of intracranial pressure alone have failed to restore cerebral metabolism and improve neurological outcome. Since mitochondrial damage results in ATP depletion and deactivation of membrane ionic pumps, we hypothesized that modulation of ATP bioavailability may directly affect cytotoxic edema. Intracranial pressure measurements were performed in Sprague-Dawley rats treated by intraperitoneal injection of dimethylsulfoxide (vehicle), cyclosporine A (CsA), or Oligomycin B (OligB) following cortical contusion and further correlated with water content, mitochondrial damage, and electron microscopic assessment of neuronal and axonal edema. As hypothesized, ultra-structural figures of edema closely correlated with intracranial pressure elevation, increased water content and mitochondrial membrane permeabilization expressed by loss of transmembrane mitochondrial potential. Further, mitochondrial damage evidenced ultra-structurally by figures of swollen mitochondria with severely distorted cristae correlated with both cytotoxic edema and mitochondrial dysfunction. Importantly, cerebral edema and mitochondrial impairment were significantly worsened by treatment with OligB, whereas a noticeable improvement could be observed in animals that received injections of CsA. Since OligB and CsA are responsible for symmetrical and opposite effects on oxidative metabolism, these findings support the hypothesis of a causative relationship between edema and mitochondrial function., (© The Author(s) 2015.)

Increasing evidence has established the involvement of the 18-kDa translocator protein (TSPO) in the process of mitochondrial membrane permeabilization and subsequent apoptosis through modulation of the mitochondrial permeability transition pore. Recent studies have shown that treatment with Ro5-4864, a TSPO ligand, resulted in a neuroprotective effect in traumatic brain injury. Yet, the nature of this effect remained uncertain as mature neurons are considered to be lacking the TSPO protein. In order to investigate the mechanism of Ro5-4864-mediated neuroprotection, the neuro-inflammatory and neurosteroid response to cortical injury was tested in sham-operated, vehicle, cyclosporine A (CsA) and Ro5-4864-treated rats. As anticipated, the levels of interleukin 1β and tumor necrosis factor α, as well as the astrocyte and microglia cellular density in the injured area were all decreased by CsA in comparison with the vehicle group. By contrast, no visible effect could be observed in Ro5-4864-treated animals. None of the groups showed any significant difference with any other in respect with the expression of brain-derived neurotrophic factor. Double immunofluorescence staining with NeuN and TSPO confirmed the absence of TSPO in native neurons though showed clear evidence of co-localization of TSPO in the cytoplasm of NeuN-stained injured neurons. Altogether, this study shows that the neuronal protection mediated by Ro5-4864 in brain injury cannot be solely attributed to an indirect effect of the ligand on glial TSPO but may also represent the consequence of the modulation of upregulated TSPO in injured neurons. This observation may be of importance for future pharmacological research in neurotrauma., (Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.)

Traumatic brain injuries represent the leading cause of death and morbidity in young adults in western countries, and are responsible for a major social and economical burden. For decades, the mainstay of neurotrauma management has been represented by control of post-traumatic edema. With the emergence of a better understanding of the underlying cellular mechanisms responsible for the generation of secondary brain damage, the hope for the "magic bullet" has prompted the development of novel drugs that have repeatedly failed to significantly improve outcome of head-injured patients. During the past decade, mitochondrial functional and structural impairment has emerged as a pivotal event in the pathway of cell to secondary death. Extensive research has identified a vast range of deleterious signals that are generated and integrated at the mitochondrial level resulting in impairment of major mitochondrial functions such as calcium homeostasis, free radicals generation and detoxification, energy production and neurosteroidogenesis. Mitochondria have therefore emerged as a potential therapeutic target. Within the spectrum of major mitochondrial structural components, the 18 kDa translocator protein (TSPO) has shown important and relevant functions such as steroid synthesis and modulation of the mitochondrial permeability transition that may substantially affect the fate of injured cells. This review summarizes the potential therapeutic implications of TSPO modulation in traumatic brain injury in the view of the current knowledge on this intriguing mitochondrial complex.

Recent experimental data have shown that hyperbaric oxygen therapy (HBOT) was associated increased Bcl-2 expression at the injury site that correlated with reduced apoptosis. We hypothesized that HBOT mediated enhancement of Bcl-2 expression and increased intracellular oxygen bio-availability may both contribute to preserve mitochondrial integrity and reduce the activation of the mitochondrial pathway of apoptosis. For this purpose, a cortical lesion was created in the parietal cortex of Sprague-Dawley rats by dynamic cortical deformation (DCD) and outcome measures in non-treated animals were compared with that of HBOT treated rats. Morphological analysis showed a profound reduction in neuronal counts in the perilesional area and a marked rarefaction of the density of the axonal-dendritic network. In treated animals, however, there was a significant attenuation of the impact of DCD over perilesional neurons, characterized by significantly higher cell counts and denser axonal network. In mitochondria isolated from injured brain tissue, there was a profound loss of mitochondrial transmembrane potential (Deltapsi(M)) that proved to be substantially reversed by HBOT. This finding correlated with a significant reduction of caspases 3 and 9 activation in HBOT treated animals but not of caspase 8, indicating a selective effect over the intrinsic pathway of apoptosis. All together, our results indicate that the neuroprotective effect of HBOT may represent the consequence of preserved mitochondrial integrity and subsequent inhibition of the mPTP and reduction of the mitochondrial pathway of apoptosis.

The growth and progression of traumatic brain injury (TBI) lesions depend significantly on developments in the traumatic penumbra area, perilesional region, where delayed neuronal death occurs. Recent data supports the important role of apoptosis in delayed cell death in TBI. Previously we demonstrated a significant reduction of apoptosis in traumatic penumbra in animals treated by hyperbaric oxygen (HBO). In this study we evaluate the expression of apoptosis-related proteins of the Bcl-2 family (Bcl-2, Bax and Bcl-xL) in the traumatic penumbra area in correlation with the extent of apoptosis in the rat model of focal cerebral contusion, treated by HBO. Sprague-Dawley rats underwent cortical dynamic deformation, some with subsequent hypoxemia. A group of both hypoxemic and non-hypoxemic animals was treated by HBO. The pathological study was based on immunohistochemical staining of the brain sections for Bcl-2, Bax and Bcl-xL with quantitative evaluation of staining by image analysis. The expression of Bcl-2 in hypoxemic animals was lower than in non-hypoxemic animals, but a significant increase in Bcl-2 expression was seen in both groups after HBO treatment. Bcl-xL also demonstrated an increase after HBO treatment but less significant. Staining for Bax protein did not demonstrate significant change after treatment. These data correlate well with the reduction of TUNEL-positive cells in traumatic penumbra after HBO treatment. We concluded that the apoptotic mechanisms are important in delayed cell death in TBI and that post-traumatic hypoxemia increases the intensity of apoptosis, probably through a decrease in Bcl-2 and Bcl-xL expression which normally repress apoptosis. The beneficial effect of HBO treatment in our model of brain contusion correlates well with the increased expression of anti-apoptotic proteins (Bcl-2 and Bcl-xL) following treatment and the appropriate decrease in the extent of apoptosis. In light of these results, the usage of HBO is justified as neuroprotective treatment in TBI.

Traumatic brain injury (TBI) is a leading cause of death and functional disability in western countries, affecting mostly young patients. Despite intense and sustained efforts deployed for the development of new therapeutic strategies, no clinical benefit has been shown by any of the investigated compounds. Increasing attention has been drawn during the past two decades to the neuroprotective effects of estrogens, although most of the available data relate to ischemic brain injury. The purpose of the present study was to investigate the potential neuroprotective value of estrogens in TBI as a therapeutic modality. For this purpose, a contusion was created in the parietal cortex by dynamic cortical deformation in two groups of 10 Sprague-Dawley male rats. Following the injury, treated animals received conjugated estrogens for 3 days, using a subcutaneously implanted osmotic pump. Animals were then sacrificed, and TUNEL, anti-active Caspase 3, bcl-2, and bax labeling were performed in paraffin-embedded brain sections, allowing for comparative and quantitative analysis. In estrogen-treated animals, there was a marked and significant reduction of apoptosis in comparison with non-treated animals. The reduction in TUNEL and active Caspase 3 staining was similar and close to 50%. Optical analysis of histological slides prepared by bcl-2 labeling showed a significant increase in bcl-2 expression in estrogen-treated animals compared to non-treated animals. On the contrary, bax expression was not influenced by hormonal treatment, and no difference could be noticed between the two groups. These results support the potential therapeutic value of estrogens in TBI and further clarify their mode of action.

Cerebral contusions are one the most frequent traumatic lesions and the most common indication for secondary surgical decompression. The purpose of this study was to investigate the physiology of perilesional secondary brain damage and evaluate the value of hyperbaric oxygen therapy (HBOT) in the treatment of these lesions. Five groups of five Sprague-Dawley rats each were submitted to dynamic cortical deformation (DCD) induced by negative pressure applied to the cortex. Cerebral lesions produced by DCD at the vacuum site proved to be reproducible. The study protocol entailed the following: (1) DCD alone, (2) DCD and HBOT, (3) DCD and post-operative hypoxia and HBOT, (4) DCD, post-operative hypoxia and HBOT, and (5) DCD and normobaric hyperoxia. Animals were sacrificed after 4 days. Histological sections showed localized gross tissue loss in the cortex at injury site, along with hemorrhage. In all cases, the severity of secondary brain damage was assessed by counting the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and caspase 3-positive cells in successive perilesional layers, each 0.5 mm thick. Perilesional TUNEL positive cells suggested the involvement of apoptosis in group 1 (12.24% of positive cells in layer 1). These findings were significantly enhanced by post-operative hypoxia (31.75%, p < 0.001). HBOT significantly reduced the severity and extent of secondary brain damage expressed by the number of TUNEL positive cells in each layer and the volume of the lesion (4.7% and 9% of TUNEL positive cells in layer 1 in groups 2 and 4 respectively, p < 0.0001 and p < 0.003). Normobaric hyperoxia also proved to be beneficial although in a lesser extent. This study demonstrates that the vacuum model of brain injury is a reproducible model of cerebral contusion. The current findings also suggest that HBOT may limit the growth of cerebral contusions and justify further experimental studies.