Effects of Caloric Restriction and Intermittent Fasting and Their Combined Exercise on Cognitive Functioning: A Review

PURPOSE OF REVIEW

The impact of dietary habits on cognitive function is increasingly gaining attention. The review is to discuss how caloric restriction (CR) and intermittent fasting (IF) can enhance cognitive function in healthy states through multiple pathways that interact with one another. Secondly, to explore the effects of CR and IF on cognitive function in conditions of neurodegenerative diseases, obesity diabetes and aging, as well as potential synergistic effects in combination with exercise to prevent cognitively related neurodegenerative diseases.

RECENT FINDINGS

With age, the human brain ages and develops corresponding neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and epilepsy, which in turn trigger cognitive impairment. Recent research indicates that the impact of diet and exercise on cognitive function is increasingly gaining attention. The benefits of exercise for cognitive function and brain plasticity are numerous, and future research can examine the efficacy of particular dietary regimens during physical activity when combined with diet which can prevent cognitive decline.

Enhancing SNR in CEST imaging: A deep learning approach with a denoising convolutional autoencoder

PURPOSE

To develop a SNR enhancement method for CEST imaging using a denoising convolutional autoencoder (DCAE) and compare its performance with state-of-the-art denoising methods.

METHOD

The DCAE-CEST model encompasses an encoder and a decoder network. The encoder learns features from the input CEST Z-spectrum via a series of one-dimensional convolutions, nonlinearity applications, and pooling. Subsequently, the decoder reconstructs an output denoised Z-spectrum using a series of up-sampling and convolution layers. The DCAE-CEST model underwent multistage training in an environment constrained by Kullback-Leibler divergence, while ensuring data adaptability through context learning using Principal Component Analysis-processed Z-spectrum as a reference. The model was trained using simulated Z-spectra, and its performance was evaluated using both simulated data and in vivo data from an animal tumor model. Maps of amide proton transfer (APT) and nuclear Overhauser enhancement (NOE) effects were quantified using the multiple-pool Lorentzian fit, along with an apparent exchange-dependent relaxation metric.

RESULTS

In digital phantom experiments, the DCAE-CEST method exhibited superior performance, surpassing existing denoising techniques, as indicated by the peak SNR and Structural Similarity Index. Additionally, in vivo data further confirm the effectiveness of the DCAE-CEST in denoising the APT and NOE maps when compared with other methods. Although no significant difference was observed in APT between tumors and normal tissues, there was a significant difference in NOE, consistent with previous findings.

CONCLUSION

The DCAE-CEST can learn the most important features of the CEST Z-spectrum and provide the most effective denoising solution compared with other methods.

Activation of the LKB1/AMPK/HIF-1α Pathway by Metformin to Promote Neovascularisation in Cerebral Ischaemia

As a difficult-to-treat neurological condition, cerebral ischemia is currently limited to treatments such as intravenous recombinant tissue plasminogen activator thrombolysis and thrombectomy. Metformin, a potent antidiabetic drug, has been reported to have an independent function in enhancing the prognosis of stroke patients, in addition to its glucose-lowering effects. However, the mechanism of action of metformin in this context remains unclear. In vivo, a rat model of permanent middle cerebral artery occlusion was established, and after administration of a low dose of 10.5 mg/mL metformin, infarct area was measured by TTC staining, and cortical blood flow was determined by laser Doppler imaging. In vitro, the study established human umbilical vein endothelial cells treated with cobalt chloride. Immunofluorescence, immunohistochemistry, and Western blot experiments were performed to observe the expression of angiogenic factors, tight junction proteins, and apoptotic factors. A TUNEL assay was utilized to appraise cell death by apoptosis. A tube formation assay and scratch assay were conducted to determine the endothelial neovascularization status. Animal experiments have revealed that the administration of the AMPK activator metformin significantly reduced the infarct area, promoted the expression of angiogenic factors, and maintained the stability of tight junction proteins in endothelial cells. Moreover, metformin reduces nerve cells apoptosis by affecting the expression of the apoptotic protein cleaved-caspase3 via the HIF-1α pathway. In vitro, the LKB1/AMPK signaling pathway is activated after hypoxic stimulation, attaining its peak within the early stages of hypoxia (1-12 h) and gradually weakening thereafter. The administration of AMPK pharmacological agonists (between 36 and 48 h) can enhance AMPK activity, which can lead to the expression of angiogenic factors, maintain the stability of tight-junction proteins in endothelial cells, and facilitate endothelial cell migration and vascular structure formation. Conversely, the AMPK inhibitors exert the opposite effects. The activation of the LKB1/AMPK/HIF-1α signaling pathway by metformin in cerebral ischemia contributes to angiogenesis, promotes tissue repair in the injured area, and enhances neurologically functional symptoms.

Reactive astrocytes generated from human iPSC are pro-inflammatory and display altered metabolism

Astrocytes are the most abundant type of glial cell in the central nervous system and they play pivotal roles in both normal health and disease. Their dysfunction is detrimental to many brain related pathologies. Under pathological conditions, such as Alzheimer's disease, astrocytes adopt an activated reactive phenotype which can contribute to disease progression. A prominent risk factor for many neurodegenerative diseases is neuroinflammation which is the purview of glial cells, such as astrocytes and microglia. Human in vitro models have the potential to reveal relevant disease specific mechanisms, through the study of individual cell types such as astrocytes or the addition of specific factors, such as those secreted by microglia. The aim of this study was to generate human cortical astrocytes, in order to assess their protein and gene expression, examine their reactivity profile in response to exposure to the microglial secreted factors IL-1α, TNFα and C1q and assess their functionality in terms of calcium signalling and metabolism. The successfully differentiated and stimulated reactive astrocytes display increased IL-6, RANTES and GM-CSF secretion, and increased expression of genes associated with reactivity including, IL-6, ICAM1, LCN2, C3 and SERPINA3. Functional assessment of these reactive astrocytes showed a delayed and sustained calcium response to ATP and a concomitant decrease in the expression of connexin-43. Furthermore, it was demonstrated these astrocytes had an increased glycolytic capacity with no effect on oxidative phosphorylation. These findings not only increase our understanding of astrocyte reactivity but also provides a functional platform for drug discovery.

Functional brain connectivity changes associated with day-to-day fluctuations in affective states

Affective neuroscience has traditionally relied on cross-sectional studies to uncover the brain correlates of affects, emotions, and moods. Such findings obfuscate intraindividual variability that may reveal meaningful changing affect states. The few functional magnetic resonance imaging longitudinal studies that have linked changes in brain function to the ebbs and flows of affective states over time have mostly investigated a single individual. In this study, we explored how the functional connectivity of brain areas associated with affective processes can explain within-person fluctuations in self-reported positive and negative affects across several subjects. To do so, we leveraged the Day2day dataset that includes 40 to 50 resting-state functional magnetic resonance imaging scans along self-reported positive and negative affectivity from a sample of six healthy participants. Sparse multivariate mixed-effect linear models could explain 15% and 11% of the within-person variation in positive and negative affective states, respectively. Evaluation of these models' generalizability to new data demonstrated the ability to predict approximately 5% and 2% of positive and negative affect variation. The functional connectivity of limbic areas, such as the amygdala, hippocampus, and insula, appeared most important to explain the temporal dynamics of affects over days, weeks, and months.

Characterization of genotype V Japanese encephalitis virus isolates from Republic of Korea

Japanese encephalitis (JE), caused by the Japanese encephalitis virus (JEV) infection, continues to pose significant public health challenges worldwide despite efficient vaccines. The virus is classified into five genotypes, among which genotype V (GV) was not detected for a long period after its initial isolation in 1952, until reports emerged from China and the Republic of Korea (ROK) since 2009. The characteristics of the virus are crucial in estimating its potential epidemiological impact. However, characterization of GV JEVs has so far been limited to two strains: Muar, the original isolate, and XZ0934, isolated in China. Two additional ROK GV JEV isolates, NCCP 43279 and NCCP 43413, are currently available, but their characteristics have not been explored. Our phylogenetic analysis revealed that GV virus sequences from the ROK segregate into two clades. NCCP 43279 and NCCP 43413 belong to different clades and exhibit distinct in vitro phenotypes. NCCP 43279 forms larger plaques but demonstrates inefficient propagation in cell culture compared to NCCP 43413. In vivo, NCCP 43279 induces higher morbidity and mortality in mice than NCCP 43413. Notably, NCCP 43279 shows more severe blood-brain barrier damage, suggesting superior brain invasion capabilities. Consistent with its higher virulence, NCCP 43279 displays more pronounced histopathological and immunopathological outcomes. In conclusion, our study confirms that the two ROK isolates are not only classified into different clades but also exhibit distinct in vitro and in vivo characteristics.

Thyroid hormone T4 mitigates traumatic brain injury in mice by dynamically remodeling cell type specific genes, pathways, and networks in hippocampus and frontal cortex

The complex pathology of mild traumatic brain injury (mTBI) is a main contributor to the difficulties in achieving a successful therapeutic regimen. Thyroxine (T4) administration has been shown to prevent the cognitive impairments induced by mTBI in mice but the mechanism is poorly understood. To understand the underlying mechanism, we carried out a single cell transcriptomic study to investigate the spatiotemporal effects of T4 on individual cell types in the hippocampus and frontal cortex at three post-injury stages in a mouse model of mTBI. We found that T4 treatment altered the proportions and transcriptomes of numerous cell types across tissues and timepoints, particularly oligodendrocytes, astrocytes, and microglia, which are crucial for injury repair. T4 also reversed the expression of mTBI-affected genes such as Ttr, mt-Rnr2, Ggn12, Malat1, Gnaq, and Myo3a, as well as numerous pathways such as cell/energy/iron metabolism, immune response, nervous system, and cytoskeleton-related pathways. Cell-type specific network modeling revealed that T4 mitigated select mTBI-perturbed dynamic shifts in subnetworks related to cell cycle, stress response, and RNA processing in oligodendrocytes. Cross cell-type ligand-receptor networks revealed the roles of App, Hmgb1, Fn1, and Tnf in mTBI, with the latter two ligands having been previously identified as TBI network hubs. mTBI and/or T4 signature genes were enriched for human genome-wide association study (GWAS) candidate genes for cognitive, psychiatric and neurodegenerative disorders related to mTBI. Our systems-level single cell analysis elucidated the temporal and spatial dynamic reprogramming of cell-type specific genes, pathways, and networks, as well as cell-cell communications as the mechanisms through which T4 mitigates cognitive dysfunction induced by mTBI.

Numerical simulation study of nanoparticle diffusion in gray matter

Purpose

Nanomedicine-based approaches have shown great potential in the treatment of central nervous system diseases. However, the fate of nanoparticles (NPs) within the brain parenchyma has not received much attention. The complexity of the microstructure of the brain and the invisibility of NPs make it difficult to study NP transport within the grey matter. Moreover, regulation of NP delivery is not fully understood.

Methods

2D interstitial system (ISS) models reflecting actual extracellular space (ECS) were constructed. A particle tracing model was used to simulate the diffusion of the NPs. The effect of NP size on NP diffusion was studied using numerical simulations. The diffusion of charged NPs was explored by comparing experimental and numerical simulation data, and the effect of cell membrane potential on the diffusion of charged NPs was further studied.

Results

The model was verified using previously published experimental data. Small NPs could diffuse efficiently into the ISS. The diffusion of charged NPs was hindered in the ISS. Changes in cell membrane potential had little effect on NP diffusion.

Conclusion

This study constructed 2D brain ISS models that reflected the actual ECS and simulated the diffusion of NPs within it. The study found that uncharged small NPs could effectively diffuse within the ISS and that the cell membrane potential had a limited effect on the diffusion of charged NPs. The model and findings of this study can aid the design of nanomedicines and nanocarriers for the diagnosis and treatment of brain diseases.

Elevated triglyceride-glucose index predicts poor outcome in patients with intracranial atherosclerotic stenosis after extracranial and intracranial bypass

BACKGROUND AND PURPOSE

The triglyceride-glucose (TyG) index, a novel reliable biomarker for IR that incorporates blood glucose and triglyceride, is linked to intracranial atherosclerotic stenosis (ICAS). In this study, we aimed to further investigate the association between the TyG index and the outcomes of ICAS patients following extracranial-to-intracranial (EC-IC) bypass grafting.

METHODS

489 ICAS patients who underwent EC-IC bypass between Jan 2009 and Jan 2022 at our hospital were retrospectively collected. The major adverse cardiac and cerebrovascular events (MACCEs), and anastomotic restenosis, both of which are critical factors leading to poor prognosis of ICAS patients after EC-IC bypass, were mainly recorded and analyzed. Kaplan-Meier survival curve and Log-rank tests were sequentially conducted. Cox regression model was used to investigate the association between the TyG index and MACCEs & anastomotic stenosis. C-statistics, continuous net reclassification improvement (NRI), and integrated discrimination improvement (IDI) evaluated the incremental predictive value of the TyG index.

RESULTS

A higher incidence of MACCEs and anastomotic stenosis was found in higher-tertile TyG index group. The TyG index was significantly associated with an increased risk of MACCEs and anastomotic stenosis, independent of confounding factors, with a value of HR (1.30, 95%CI 1.10-1.51, p < 0.001) and (1.27, 95%CI 1.16-1.40, p < 0.001) respectively. The area under the curve (AUC) in the model with the TyG index for predicting the occurrence of MACCEs and anastomotic stenosis were 0.708 (95%CI 0.665-0.748) and 0.731 (95%CI 0.689-0.770) respectively. The addition of the TyG index significantly improved the global performance of the baseline model according to the C-statistics, NRI, and IDI (All p < 0.05).

CONCLUSIONS

Higher TyG levels were associated with poorer outcomes in ICAS patients after EC-IC bypass. TyG could be a key factor in managing ICAS risk and standardizing the indications for EC-IC bypass.

Repressing iron overload ameliorates central post-stroke pain via the Hdac2-Kv1.2 axis in a rat model of hemorrhagic stroke

JOURNAL/nrgr/04.03/01300535-202412000-00027/figure1/v/2024-04-08T165401Z/r/image-tiff Thalamic hemorrhage can lead to the development of central post-stroke pain. Changes in histone acetylation levels, which are regulated by histone deacetylases, affect the excitability of neurons surrounding the hemorrhagic area. However, the regulatory mechanism of histone deacetylases in central post-stroke pain remains unclear. Here, we show that iron overload leads to an increase in histone deacetylase 2 expression in damaged ventral posterolateral nucleus neurons. Inhibiting this increase restored histone H3 acetylation in the Kcna2 promoter region of the voltage-dependent potassium (Kv) channel subunit gene in a rat model of central post-stroke pain, thereby increasing Kcna2 expression and relieving central pain. However, in the absence of nerve injury, increasing histone deacetylase 2 expression decreased Kcna2 expression, decreased Kv current, increased the excitability of neurons in the ventral posterolateral nucleus area, and led to neuropathic pain symptoms. Moreover, treatment with the iron chelator deferiprone effectively reduced iron overload in the ventral posterolateral nucleus after intracerebral hemorrhage, reversed histone deacetylase 2 upregulation and Kv1.2 downregulation, and alleviated mechanical hypersensitivity in central post-stroke pain rats. These results suggest that histone deacetylase 2 upregulation and Kv1.2 downregulation, mediated by iron overload, are important factors in central post-stroke pain pathogenesis and could serve as new targets for central post-stroke pain treatment.

TRPM2 knockdown attenuates myocardial apoptosis and promotes autophagy in HFD/STZ-induced diabetic mice via regulating the MEK/ERK and mTORC1 signaling pathway

Diabetic cardiomyopathy (DCM) is a major complication of diabetes. Transient receptor potential melastatin 2 (TRPM2) activity increases in diabetic oxidative stress state, and it is involved in myocardial damage and repair. We explore the protective effect of TRPM2 knockdown on the progression of DCM. A type 2 diabetes animal model was established in C57BL/6N mice by long-term high-fat diet (HFD) feeding combined with a single injection of 100-mg/kg streptozotocin (STZ). Genetic knockdown of TRPM2 in heart was accomplished by the intravenous injection via the tail vein of adeno-associated virus type 9 carrying TRPM2 shRNA. Neonatal rat ventricular myocytes was exposed to 45 mM of high-glucose (HG) stimulation for 72 h in vitro to mimic the in vivo conditions. Western blot, real-time quantitative PCR (RT-qPCR), immunohistochemistry and fluorescence, electron, CCK-8, and flow cytometry were used to evaluate the phenotype of cardiac inflammation, fibrosis, apoptosis, and autophagy. Mice with HFD/STZ-induced diabetes exhibited systolic and diastolic dysfunction, as demonstrated by increased myocardial apoptosis and autophagy inhibition in the heart. Compared to control group, the protein expression of TRPM2, bax, cleaved caspase-3, and P62 was significantly elevated, and the protein expression of bcl-2 and LC3-II was significantly decreased in the myocardial tissues of the HFD/STZ-induced diabetes group. Knockdown of TRPM2 significantly reversed the HFD/STZ-induced myocardial apoptosis and autophagy inhibition. TRPM2 silencing attenuated HG-induced apoptosis and autophagy inhibition in primary cardiomyocytes via regulating the MEK/ERK mTORC1 signaling pathway. TRPM2 knockdown attenuates hyperglycemia-induced myocardial apoptosis and promotes autophagy in HFD/STZ-induced diabetic mice or HG-stimulated cardiomyocytes via regulating the MEK/ERK and mTORC1 signaling pathway.

Treatment of Stroke at a Delayed Timepoint with a Repurposed Drug Targeting Sigma 1 Receptors

Sigma 1 receptors are intracellular chaperone proteins that have been explored as a subacute treatment to enhance post-stroke recovery. We recently identified the antitussive oxeladin as a selective sigma 1 receptor agonist with the ability to stimulate the release of brain-derived neurotrophic factor from neurons in vitro. In this study, we hypothesized that oral oxeladin citrate would stimulate BDNF secretion and improve stroke outcomes when administered to male rats starting 48 h after transient middle cerebral artery occlusion. Oxeladin did not alter blood clotting and crossed the blood brain barrier within 30 min of oral administration. Rats underwent 90 min of transient middle cerebral artery occlusion. Forty-eight hours later rats began receiving daily oxeladin (135 mg/kg) for 11 days. Oxeladin significantly improved neurological function on days 3, 7, and 14 following MCAO. Infarct size was not altered by a single dose, but the final extent of infarct after 14 days was decreased. However, there was no significant reduction in astrogliosis or microgliosis compared to vehicle-treated control rats. In agreement with in vitro studies, oxeladin increased the amount of mature BDNF in the cerebral cortex 2, 6, and 24 h after single oral dose. However, the increase in BDNF did not result in increases in cellular proliferation in the subventricular zone or dentate gyrus when compared to vehicle-treated controls. These results suggest that oxeladin may reduce the extent of infarct expansion in the subacute phase of stroke, although this action does not appear to involve a reduction in inflammation or increased cell proliferation.

The hydroxycarboxylic acid receptor HCA2 is required for the protective effect of ketogenic diet in epilepsy

One third of epilepsy patients are resistant to treatment with current anti-seizure medications. The ketogenic diet is used to treat some forms of refractory epilepsy, but the mechanism of its action has not yet been elucidated. In this study, we aimed to investigate whether the hydroxycarboxylic acid receptor 2 (HCA2), a known immunomodulatory receptor, plays a role in mediating the protective effect of this diet. We demonstrate for the first time that selective agonists at this receptor can directly reduce seizures in animal models. Agonists also reduce network activity in rodent and human brain slices. Ketogenic diet is known to increase circulating levels of endogenous HCA2 agonists, and we show that the effect of ketogenic diet in reducing seizures in the 6 Hz seizure model is negated in HCA2-deficient mice. Our data support the potential of HCA2 as a target for the treatment of epilepsy and potentially for neurodegenerative diseases.

The gut microbiome and the brain

PURPOSE OF REVIEW

The importance of the gut microbiome for human health and well-being is generally accepted, and elucidating the signaling pathways between the gut microbiome and the host offers novel mechanistic insight into the (patho)physiology and multifaceted aspects of healthy aging and human brain functions.

RECENT FINDINGS

The gut microbiome is tightly linked with the nervous system, and gut microbiota are increasingly emerging as important regulators of emotional and cognitive performance. They send and receive signals for the bidirectional communication between gut and brain via immunological, neuroanatomical, and humoral pathways. The composition of the gut microbiota and the spectrum of metabolites and neurotransmitters that they release changes with increasing age, nutrition, hypoxia, and other pathological conditions. Changes in gut microbiota (dysbiosis) are associated with critical illnesses such as cancer, cardiovascular, and chronic kidney disease but also neurological, mental, and pain disorders, as well as chemotherapies and antibiotics affecting brain development and function.

SUMMARY

Dysbiosis and a concomitant imbalance of mediators are increasingly emerging both as causes and consequences of diseases affecting the brain. Understanding the microbiota's role in the pathogenesis of these disorders will have major clinical implications and offer new opportunities for therapeutic interventions.

Cerebral hemodynamic and systemic physiological changes in trained freedivers completing sled-assisted dives to two different depths

Although existing literature covers significant detail on the physiology of human freediving, the lack of standardized protocols has hindered comparisons due to confounding variables such as exercise and depth. By accounting for these variables, direct depth-dependent impacts on cardiovascular and blood oxygen regulation can be investigated. In this study, depth-dependent effects on 1) cerebral hemodynamic and oxygenation changes, 2) arterial oxygen saturation ([Formula: see text]), and 3) heart rate during breath-hold diving without confounding effects of exercise were investigated. Six freedivers (51.0 ± 12.6 yr; means ± SD), instrumented with continuous-wave near-infrared spectroscopy for monitoring cerebral hemodynamic and oxygenation measurements, heart rate, and [Formula: see text], performed sled-assisted breath-hold dives to 15 m and 42 m. Arterial blood gas tensions were validated through cross-sectional periodic blood sampling. Cerebral hemodynamic changes were characteristic of breath-hold diving, with changes during ascent from both depths likely driven by decreasing [Formula: see text] due to lung expansion. Although [Formula: see text] was significantly lower following 42-m dives [t(5) = -4.183, P < 0.05], mean cerebral arterial-venous blood oxygen saturation remained at 74% following dives to both depths. Cerebral oxygenation during ascent from 42 m may have been maintained through increased arterial delivery. Heart rate was variable with no significant difference in minimum heart rate between both depths [t(5) = -1.017, P > 0.05]. This study presents a standardized methodology, which could provide a basis for future research on human freediving physiology and uncover ways in which freedivers can reduce potential risks of the sport.NEW & NOTEWORTHY We present a standardized methodology in which trained breath-hold divers instrumented with wearable near-infrared spectroscopy (NIRS) technology and a cannula for arterial blood sampling completed sled-assisted dives to two different dive depths to account for the confounding factors of exercise and depth during breath-hold diving. In our investigation, we highlight the utility of wearable NIRS systems for continuous hemodynamic and oxygenation monitoring to investigate the impacts of hydrostatic pressure on cardiovascular and blood oxygen regulation.

The brain's duck test in phantom percepts: Multisensory congruence in neuropathic pain and tinnitus

Chronic neuropathic pain and chronic tinnitus have been likened to phantom percepts, in which a complete or partial sensory deafferentation results in a filling in of the missing information derived from memory. 150 participants, 50 with tinnitus, 50 with chronic pain and 50 healthy controls underwent a resting state EEG. Source localized current density is recorded from all the sensory cortices (olfactory, gustatory, somatosensory, auditory, vestibular, visual) as well as the parahippocampal area. Functional connectivity by means of lagged phase synchronization is also computed between these regions of interest. Pain and tinnitus are associated with gamma band activity, reflecting prediction errors, in all sensory cortices except the olfactory and gustatory cortex. Functional connectivity identifies theta frequency connectivity between each of the sensory cortices except the chemical senses to the parahippocampus, but not between the individual sensory cortices. When one sensory domain is deprived, the other senses may provide the parahippocampal 'contextual' area with the most likely sound or somatosensory sensation to fill in the gap, applying an abductive 'duck test' approach, i.e., based on stored multisensory congruence. This novel concept paves the way to develop novel treatments for pain and tinnitus, using multisensory (i.e. visual, vestibular, somatosensory, auditory) modulation with or without associated parahippocampal targeting.

Association of early changes in arterial carbon dioxide with acute brain injury in adult patients with extracorporeal membrane oxygenation: A ten-year retrospective study in a German tertiary care hospital

PURPOSE

To assess the association between fluctuations of arterial carbon dioxide early after start of extracorporeal membrane oxygenation (ECMO) with intracranial hemorrhage (ICH) or ischemic stroke (IS).

MATERIALS AND METHODS

This single-center retrospective study included patients who required ECMO for circulatory or respiratory failure between January 2011 and April 2021 and for whom a cerebral computed tomography (cCT) scan was available. Multivariable logistic regression models were fitted to evaluate the association between the relative change of arterial carbon dioxide (RelΔPaCO2) and ICH, IS or a composite of ICH, IS, and mortality.

RESULTS

In 618 patients (venovenous ECMO: n = 295; venoarterial ECMO: n = 323) ICH occurred more frequently in patients with respiratory failure (19.0%) compared with patients with circulatory failure (6.8%). Conversely, the incidence of IS was higher in patients with circulatory failure (19.2%) compared with patients with respiratory failure (4.7%). While patients with ECMO for respiratory failure were more likely to have ICH (OR 3.683 [95% CI: 1.855;7.309], p < 0.001), they had a lower odds for IS (OR 0.360 [95%CI: 0.158;0.820], p = 0.015) compared with patients with circulatory failure. There was no significant association between RelΔPaCO2 and ICH or IS.

CONCLUSIONS

Irrespective of the indication for ECMO, we did not find a significant association between the relative change in PaCO2 early after ECMO initiation and acute brain injury. Aside from early PaCO2 decline at cannulation, future studies should address fluctuations of PaCO2 throughout the course of ECMO support and their effect on acute brain injury.

Metabolic resistance of Aβ3pE-42, a target epitope of the anti-Alzheimer therapeutic antibody, donanemab

The amyloid β peptide (Aβ), starting with pyroglutamate (pE) at position 3 and ending at position 42 (Aβ3pE-42), predominantly accumulates in the brains of Alzheimer's disease. Consistently, donanemab, a therapeutic antibody raised against Aβ3pE-42, has been shown to be effective in recent clinical trials. Although the primary Aβ produced physiologically is Aβ1-40/42, an explanation for how and why this physiological Aβ is converted to the pathological form remains elusive. Here, we present experimental evidence that accounts for the aging-associated Aβ3pE-42 deposition: Aβ3pE-42 was metabolically more stable than other Aβx-42 variants; deficiency of neprilysin, the major Aβ-degrading enzyme, induced a relatively selective deposition of Aβ3pE-42 in both APP transgenic and App knock-in mouse brains; Aβ3pE-42 deposition always colocalized with Pittsburgh compound B-positive cored plaques in APP transgenic mouse brains; and under aberrant conditions, such as a significant reduction in neprilysin activity, aminopeptidases, dipeptidyl peptidases, and glutaminyl-peptide cyclotransferase-like were up-regulated in the progression of aging, and a proportion of Aβ1-42 may be processed to Aβ3pE-42. Our findings suggest that anti-Aβ therapies are more effective if given before Aβ3pE-42 deposition.

Fast and motion-robust saturation transfer MRI with inherent B0 correction using rosette trajectories and compressed sensing

PURPOSE

To implement rosette readout trajectories with compressed sensing reconstruction for fast and motion-robust CEST and magnetization transfer contrast imaging with inherent correction of B0 inhomogeneity.

METHODS

A pulse sequence was developed for fast saturation transfer imaging using a stack of rosette trajectories with a higher sampling density near the k-space center. Each rosette lobe was segmented into two halves to generate dual-echo images. B0 inhomogeneities were estimated using the phase difference between the images and corrected subsequently. The rosette-based imaging was evaluated in comparison to a fully sampled Cartesian trajectory and demonstrated on CEST phantoms (creatine solutions and egg white) and healthy volunteers at 3 T.

RESULTS

Compared with the conventional Cartesian acquisition, compressed sensing reconstructed rosette images provided image quality with overall higher contrast-to-noise ratio and significantly faster readout time. Accurate B0 map estimation was achieved from the rosette acquisition with a negligible bias of 0.01 Hz between the rosette and dual-echo Cartesian gradient echo B0 maps, using the latter as ground truth. The water-saturation spectra (Z-spectra) and amide proton transfer weighted signals obtained from the rosette-based sequence were well preserved compared with the fully sampled data, both in the phantom and human studies.

CONCLUSIONS

Fast, motion-robust, and inherent B0-corrected CEST and magnetization transfer contrast imaging using rosette trajectories could improve subject comfort and compliance, contrast-to-noise ratio, and provide inherent B0 homogeneity information. This work is expected to significantly accelerate the translation of CEST-MRI into a robust, clinically viable approach.

Activation of chaperone-mediated autophagy exerting neuroprotection effect on intracerebral hemorrhage-induced neuronal injury by targeting Lamp2a

Intracerebral hemorrhage (ICH) is a common and devastating type of stroke, marked by significant morbidity and a grim prognosis. The inflammation cascade triggered by astrocytes plays a critical role in secondary brain injury (SBI) following ICH, leading to detrimental effects such as cell death. However, effective intervention strategies are currently lacking. This study aims to investigate the role of the astrocyte cascade reaction following ICH and identify potential intervention targets. Utilizing the GSE216607 and GSE206971 databases for analysis, we established a mouse autologous blood model. Firstly, our research revealed a significant activation of the autophagy pathway following intracerebral hemorrhage (ICH), with a notable upregulation of Lamp2a, a key factor in chaperone-mediated autophagy (CMA), primarily localized in astrocytes. Additionally, the downregulation of Lamp2a resulted in a significant augmentation of A1 reactive astrocytes, concomitant with a reduction in myelin coverage area, heightened neuronal injury, exacerbated motor and sensory deficits, and diminished neurological scores after ICH in mice. Conversely, CA77.1, an activator of CMA, could reverse ICH-induced augmentation of A1 reactive astrocytes, myelin damage, neuronal death, and neurobehavioral disorders. In conclusion, the activation of astrocyte CMA following ICH can exert neuroprotective effects. Lamp2a represents a promising therapeutic target for post-ICH treatment.

Validation of optimised intracranial spectroscopic probe for instantaneous in-situ monitoring and classification of traumatic brain injury

The development of an optical interface to directly distinguish the brain tissue's biochemistry is the next step in understanding traumatic brain injury (TBI) pathophysiology and the best and most appropriate treatment in cases where in-hospital intracranial access is required. Despite TBI being a globally leading cause of morbidity and mortality in patients under 40, there is still a lack of objective diagnostical tools. Further, given its pathophysiological complexity the majority of treatments provided are purely symptomatic without standardized therapeutic targets. Our tailor-engineered prototype of the intracranial Raman spectroscopy probe (Intra-RSP) is designed to bridge the gap and provide real-time spectroscopic insights to monitor TBI and its evolution as well as identify patient-specific molecular targets for timely intervention. Raman spectroscopy being rapid, label-free and non-destructive, renders it an ideal portable diagnostics tool. In combination with our in-house developed software, using machine learning algorithms for multivariate analysis, the Intra-RSP is shown to accurately differentiate simulated TBI conditions in rat brains from the healthy controls, directly from the brain surface as well as through the rat's skull. Using clinically pre-established methods of cranial entry, the Intra-RSP can be inserted into a 2-piece optimised cranial bolt with integrated focussing and correctly identify a sample in real-life conditions with an accuracy >80 %. To further validate the Intra-RSP's efficiency as a TBI monitoring device, rat brains mildly damaged from inflicted spinal cord injury were found to be correctly classified with 94.5 % accuracy. Through optimization and rigorous in-vivo validation, the Intra-RSP prototype is envisioned to seamlessly integrate into existing standards of neurological care, serving as a minimally invasive, in-situ neuromonitoring tool. This transformative approach has the potential to revolutionize the landscape of neurological care by providing clinicians with unprecedented insights into the nature of brain injuries and fostering targeted, timely and effective therapeutic interventions.

Linking peripheral atherosclerosis to blood-brain barrier disruption: elucidating its role as a manifestation of cerebral small vessel disease in vascular cognitive impairment

Aging plays a pivotal role in the pathogenesis of cerebral small vessel disease (CSVD), contributing to the onset and progression of vascular cognitive impairment and dementia (VCID). In older adults, CSVD often leads to significant pathological outcomes, including blood-brain barrier (BBB) disruption, which in turn triggers neuroinflammation and white matter damage. This damage is frequently observed as white matter hyperintensities (WMHs) in neuroimaging studies. There is mounting evidence that older adults with atherosclerotic vascular diseases, such as peripheral artery disease, ischemic heart disease, and carotid artery stenosis, face a heightened risk of developing CSVD and VCID. This review explores the complex relationship between peripheral atherosclerosis, the pathogenesis of CSVD, and BBB disruption. It explores the continuum of vascular aging, emphasizing the shared pathomechanisms that underlie atherosclerosis in large arteries and BBB disruption in the cerebral microcirculation, exacerbating both CSVD and VCID. By reviewing current evidence, this paper discusses the impact of endothelial dysfunction, cellular senescence, inflammation, and oxidative stress on vascular and neurovascular health. This review aims to enhance understanding of these complex interactions and advocate for integrated approaches to manage vascular health, thereby mitigating the risk and progression of CSVD and VCID.

Endothelin-1 increases Na+-K+-2Cl- cotransporter-1 expression in cultured astrocytes and in traumatic brain injury model: An involvement of HIF1α activation

Na+-K+-2Cl- cotransporter-1 (NKCC1) is present in brain cells, including astrocytes. The expression of astrocytic NKCC1 increases in the acute phase of traumatic brain injury (TBI), which induces brain edema. Endothelin-1 (ET-1) is a factor that induces brain edema and regulates the expression of several pathology-related genes in astrocytes. In the present study, we investigated the effect of ET-1 on NKCC1 expression in astrocytes. ET-1 (100 nM)-treated cultured astrocytes showed increased NKCC1 mRNA and protein levels. The effect of ET-1 on NKCC1 expression in cultured astrocytes was reduced by BQ788 (1 μM), an ETB antagonist, but not by FR139317 (1 μM), an ETA antagonist. The involvement of ET-1 in NKCC1 expression in TBI was examined using a fluid percussion injury (FPI) mouse model that replicates the pathology of TBI with high reproducibility. Administration of BQ788 (15 nmol/day) decreased FPI-induced expressions of NKCC1 mRNA and protein, accompanied with a reduction of astrocytic activation. FPI-induced brain edema was attenuated by BQ788 and NKCC1 inhibitors (azosemide and bumetanide). ET-1-treated cultured astrocytes showed increased mRNA and protein expression of hypoxia-inducible factor-1α (HIF1α). Immunohistochemical observations of mouse cerebrum after FPI showed co-localization of HIF1α with GFAP-positive astrocytes. Increased HIF1α expression in the TBI model was reversed by BQ788. FM19G11 (an HIF inhibitor, 1 μM) and HIF1α siRNA suppressed ET-induced increase in NKCC1 expression in cultured astrocytes. These results indicate that ET-1 increases NKCC1 expression in astrocytes through the activation of HIF1α.

Identification of Non-excitatory Amino Acids and Transporters Mediating the Irreversible Synaptic Silencing After Hypoxia

The contribution of excitatory amino acids (AA) to ischemic brain injury has been widely described. In addition, we reported that a mixture of non-excitatory AA at plasmatic concentrations turns irreversible the depression of synaptic transmission caused by hypoxia. Here, we describe that the presence of seven non-excitatory AA (L-alanine, L-glutamine, glycine, L-histidine, L-serine, taurine, and L-threonine) during hypoxia provokes an irreversible neuronal membrane depolarization, after an initial phase of hyperpolarization. The collapse of the membrane potential correlates with a great increase in fiber volley amplitude. Nevertheless, we show that the presence of all seven AA is not necessary to cause the irreversible loss of fEPSP after hypoxia and that the minimal combination of AA able to provoke a solid, replicable effect is the mixture of L-alanine, glycine, L-glutamine, and L-serine. Additionally, L-glutamine seems necessary but insufficient to induce these harmful effects. We also prove that the deleterious effects of the AA mixtures on field potentials during hypoxia depend on both the identity and concentration of the individual AA in the mixture. Furthermore, we find that the accumulation of AA in the whole slice does not determine the outcome caused by the AA mixtures on the synaptic transmission during hypoxia. Finally, results obtained using pharmacological inhibitors and specific substrates of AA transporters suggest that system N and the alanine-serine-cysteine transporter 2 (ASCT2) participate in the non-excitatory AA-mediated deleterious effects during hypoxia. Thus, these AA transporters might represent therapeutical targets for the treatment of brain ischemia.

Neurological and Systemic Pitfalls in the Diagnosis of Cluster Headaches: A Case-Based Review

PURPOSE OF REVIEW

To describe different pitfalls in the diagnosis of primary cluster headaches (CHs) with the guidance of seven case vignettes.

RECENT FINDINGS

The question of whether primary CHs and migraines are totally different entities has been long debated. Autonomic features can be detected in as many as 60% of migraine patients. Although some genetic similarities have been found, CACNA1A mutations have not been detected among CH patients with hemimotor aura in contrast to hemiplegic migraine. Recently, functional MRI studies have shown that the left thalamic network was the most discriminative MRI feature in distinguishing migraine from CH patients. Compared to migraine, CH patients showed decreased functional interaction between the left thalamus and cortical areas mediating interception and sensory integration. However, clinically the most significant feature had been the restlessness and agitation seen during headache attacks patients with CHs. This feature is also important in distinguishing cluster patients from other patients having other trigeminal autonomic cephalalgias except for a subset of patients with hemicrania continua. CH is an important member of the group of headache disorders characterized by their association with one or more autonomic features in the trigeminal nerve distribution and termed Trigeminal Autonomic Cephalalgias (TACs). Although CH is a relatively rare condition, judged by the distress it generally causes to the affected individual, early diagnosis and institution of appropriate therapy seem mandatory. Correct diagnosis of CHs needs avoidance of pitfalls. Such pitfalls generally include differentiation from migraine, differentiation from other side locked headache disorders, from other trigeminal autonomic cephalalgias (TACs), and lastly, recognition of rare presentations of cluster-like manifestations with hemiplegic aura and simulating trigeminal and glossopharyngeal neuralgias. Differentiation between primary and symptomatic CHs related to sellar pathologies and systemic medical conditions is of equal importance. In the present review such issues are discussed with the assistance of seven case vignettes.

Understanding Headaches Attributed to Cranial and/or Cervical Vascular Disorders: Insights and Challenges for Neurologists

In recent decades, cranial and cervical vascular disorders have become major global health concerns, significantly impacting patients, families, and societies. Headache is a prevalent symptom of these vascular diseases and can often be the initial, primary, or sole manifestation. The intricate relationship between headaches and cranial/cervical vascular disorders poses a diagnostic and therapeutic challenge, with the underlying mechanisms remaining largely elusive. Understanding this association is crucial for the early diagnosis, prevention, and intervention of such conditions. This review aims to provide a comprehensive overview of the clinical features and potential pathogenesis of headaches attributed to cranial and cervical vascular disorders and provide a reference for disease management and a basis for potential pathological mechanisms.

A novel transgenic mouse model highlights molecular disruptions involved in the pathogenesis of Dent disease 1

Dent disease (DD) is a hereditary renal disorder characterized by low molecular weight (LMW) proteinuria and progressive renal failure. Inactivating mutations of the CLCN5 gene encoding the 2Cl-/H+exchanger ClC-5 have been identified in patients with DD type 1. ClC-5 is essentially expressed in proximal tubules (PT) where it is thought to play a role in maintaining an efficient endocytosis of LMW proteins. However, the exact pathological roles of ClC-5 in progressive dysfunctions observed in DD type 1 are still unclear. To address this issue, we designed a mouse model carrying the most representative type of ClC-5 missense mutations found in DD patients. These mice showed a characteristic DD type 1 phenotype accompanied by altered endo-lysosomal system and autophagy functions. With ageing, KI mice showed increased renal fibrosis, apoptosis and major changes in cell metabolic functions as already suggested in previous DD models. Furthermore, we made the interesting new discovery that the Lipocalin-2-24p3R pathway might be involved in the progression of the disease. These results suggest a crosstalk between the proximal and distal nephron in the pathogenesis mechanisms involved in DD with an initial PT impairment followed by the Lipocalin-2 internalisation and 24p3R overexpression in more distal segments of the nephron. This first animal model of DD carrying a pathogenic mutation of Clcn5 and our findings pave the way aimed at exploring therapeutic strategies to limit the consequences of ClC-5 disruption in patients with DD type 1 developing chronic kidney disease.

A rat model of cerebral small vascular disease induced by ultrasound and protoporphyrin

Cerebral small vascular disease (CSVD) has a high incidence worldwide, but its pathological mechanisms remain poorly understood due to the lack of proper animal models. The current animal models of CSVD have several limitations such as high mortality rates and large-sized lesions, and thus it is urgent to develop new animal models of CSVD. Ultrasound can activate protoporphyrin to produce reactive oxygen species in a liquid environment. Here we delivered protoporphyrin into cerebral small vessels of rat brain through polystyrene microspheres with a diameter of 15 μm, and then performed transcranial ultrasound stimulation (TUS) on the model rats. We found that TUS did not affect the large vessels or cause large infarctions in the brain of model rats. The mortality rates were also comparable between the sham and model rats. Strikingly, TUS induced several CSVD-like phenotypes such as cerebral microinfarction, white matter injuries and impaired integrity of endothelial cells in the model rats. Additionally, these effects could be alleviated by antioxidant treatment with N-acetylcysteine (NAC). As control experiments, TUS did not lead to cerebral microinfarction in the rat brain when injected with the polystyrene microspheres not conjugated with protoporphyrin. In sum, we generated a rat model of CSVD that may be useful for the mechanistic study and drug development for CSVD.

Effect of Hemoglobin and Blood Glucose Levels on CT Perfusion Ischemic Core Estimation: A Post Hoc Analysis of the ESCAPE-NA1 Trial

BACKGROUND AND OBJECTIVES

CT perfusion (CTP) maps can estimate the ischemic core in acute ischemic stroke based on distinctive cerebral blood flow thresholds. However, metabolic factors beyond perfusion influence the tissue tolerance to ischemia and the infarct growth rate. Underestimating the ischemic core volume (ICV) might result in overestimating the salvageable cerebral tissue and, consequently, overestimating the potential clinical benefits of reperfusion therapies. We aim to evaluate whether baseline hemoglobin and blood glucose levels influence the accuracy of baseline CTP ICV estimations.

METHODS

Large vessel occlusion stroke patients investigated with baseline CTP undergoing thrombectomy with near-complete reperfusion and without parenchymal hemorrhage from the ESCAPE-NA1 trial were included. Patients were subdivided into anemic (hemoglobin <130 g/L for men and <120 g/L for women) and nonanemic groups, and hyperglycemic (blood glucose level >7 mmol/L) and normoglycemic groups. Ischemic core underestimated volume (ICuV) was calculated: final infarct volume minus CTP-based ICV. The primary outcome was the presence of "perfusion scotoma" defined as ICuV ≥10 mL. Presence of "perfusion scotoma" and median ICuV were compared between anemic vs nonanemic and hyperglycemic vs normoglycemic patients using nonparametric tests and multivariable binary logistic regression with adjustment for baseline variables.

RESULTS

One hundred sixty-two of 1,105 (15%) patients were included (median age 70.5 [interquartile range (IQR) 61-80.4], 50.6% women). The median ICuV was 7.26 mL (IQR 0-25.63). Seventy-eight (48%) patients demonstrated perfusion scotoma. Forty-two (25.7%) patients were anemic, and 65 (40.1%) were hyperglycemic. In univariable analysis, the hyperglycemic group had a higher prevalence of perfusion scotoma (65% [n = 40] vs 39% [n = 38], p = 0.006) and larger ICuV (17.79 mL [IQR 1.57-42.75] vs 6 mL [-0.31 to 12.51], p = 0.003) compared to normoglycemic patients. No significant ICuV differences between patients with and without anemia were seen. Multivariable regression analysis revealed an association between perfusion scotoma and hyperglycemia, adjusted odds ratio (OR) 2.48 (95% CI 1.25-4.92), and between perfusion scotoma and blood glucose levels, adjusted OR 1.19 (95% CI 1.03-1.39) per 1 mmol/L increase.

DISCUSSION

In our study, CTP-based ischemic core underestimation was common and associated with higher baseline blood glucose levels. Individual metabolic factors beyond perfusion that critically influence the infarct growth rate should be considered when interpreting baseline CTP estimations of ischemic core.

Prevalence and Clinical Implications of Hemosiderin Deposits in Recent Small Subcortical Infarcts

BACKGROUND AND OBJECTIVES

A quarter of ischemic strokes are of lacunar clinical subtype and have an underlying recent small subcortical infarct (RSSI), but their long-term outcomes remain poorly characterized. Hemosiderin deposits (HDs) have been noted in RSSIs at chronic stages and might mimic primary hemorrhage. We characterized HDs' morphology, frequency, and clinical relevance.

METHODS

Participants with RSSIs were identified from a prospective longitudinal study and evaluated on 3T MRI including susceptibility-weighted imaging (SWI) from stroke diagnosis to 12 months. We categorized HDs in RSSIs on SWI at all available time points into 4 types (spots, smudge, rim, cluster) and assessed their associations with demographic factors, stroke-related factors, and image markers with adjusted logistic regression.

RESULTS

HDs were observed in 43 (55.0%) of 108 participants within 3 months and 83 (76.9%) of 108 within 12 months after stroke onset. The mean time to first detection of HDs was 87 (interquartile range 53-164) days. A "rim" pattern (similar to late appearance of primary hemorrhage) occurred in at least 26.5% of RSSIs at all follow-up time points, mainly those located in the lentiform/internal capsule (50.0%) or thalamus (36.4%). Infarct volume (odds ratio [OR] 1.003, 95% CI 1.001-1.006; p = 0.004) and the total small vessel disease (SVD) score at baseline (OR 2.50, 95% CI 1.28-4.86, p = 0.007) independently predicted HDs at 12 months. HDs were positively associated with more lacunes (OR 1.60, 95% CI 1.13-2.26, p < 0.01), but not the Fazekas score, number of microbleeds, basal ganglia mineral deposit score, or clinical outcomes.

DISCUSSION

HDs occur commonly in RSSIs and may be associated with infarct volume and SVD score. Hemosiderin "rim" is common in RSSIs, urging caution to avoid mistaking ischemic RSSI for primary hemorrhage in subacute and chronic stages.

Continuous theta burst stimulation ameliorates cognitive deficits in microinfarcts mice via inhibiting glial activation and promoting paravascular CSF-ISF exchange

Microinfarcts are widespread in the elderly, accompanied by varying degrees of cognitive decline. Continuous theta burst stimulation (cTBS) has been demonstrated to be neuroprotective on cognitive dysfunction, but the underlying cellular mechanism has been still not clear. In the present study, we evaluated the effects of cTBS on cognitive function and brain pathological changes in mice model of microinfarcts. The spatial learning and memory was assessed by Morris water maze (MWM), Glymphatic clearance efficiency was evaluated using in vivo two-photon imaging. The loss of neurons, activation of astrocytes and microglia, the expression and polarity distribution of the astrocytic aquaporin-4 (AQP4) were assessed by immunofluorescence staining. Our results showed that cTBS treatment significantly improved the spatial learning and memory, accelerated the efficiency of glymphatic clearance, up-regulated the AQP4 expression and improved the polarity distribution of AQP4 in microinfarcts mice. Besides, cTBS treatment increased the number of surviving neurons, whereas decreased the activated astrocytes and microglia. Our study suggested that cTBS accelerated glymphatic clearance and inhibited the excessive gliogenesis, which ultimately exerted neuroprotective effects on microinfarcts mice.

TREM1 promotes neuroinflammation after traumatic brain injury in rats: Possible involvement of ERK/cPLA2 signalling pathway

The neuroinflammatory response promotes secondary brain injury after traumatic brain injury (TBI). Triggering receptor expressed on myeloid cells 1 (TREM1) is a key regulator of inflammation. However, the role of TREM1 in TBI is poorly studied. The purpose of this study was to investigate the role of TREM1 in TBI and the possible underlying mechanism. We found that the protein expression of TREM1 significantly increased after TBI in rats, and the TREM1 protein localized to microglia. Inhibition of the TREM1 protein with LP17 significantly blocked ERK phosphorylation and reduced cytoplasmic phospholipase A2 (cPLA2) protein expression and phosphorylation. In addition, LP17-mediated TREM1 inhibition significantly reduced the protein expression of iNOS and increased the protein expression of Arg1. Moreover, after TREM1 was inhibited, the secretion of the proinflammatory factors TNF-α and IL-1β was significantly reduced, while the secretion of the anti-inflammatory factors IL-4 and IL-10 was significantly increased. Additionally, inhibition of TREM1 by LP17 significantly reduced neuronal apoptosis and ameliorated nerve dysfunction in TBI model rats. In conclusion, our findings suggest that TREM1 enhances neuroinflammation and promotes neuronal apoptosis after TBI, and these effects may be partly mediated via the ERK/cPLA2 signalling pathway.

CD36-mediated ROS/PI3K/AKT signaling pathway exacerbates cognitive impairment in APP/PS1 mice after noise exposure

There is an association between noise exposure and cognitive impairment, and noise may have a more severe impact on patients with Alzheimer's disease (AD) and mild cognitive impairment; however, the mechanisms need further investigation. This study used the classic AD animal model APP/PS1 mice to simulate the AD population, and C57BL/6J mice to simulate the normal population. We compared their cognitive abilities after noise exposure, analyzed changes in Cluster of Differentiation (CD) between the two types of mice using transcriptomics, identified the differential CD molecule: CD36 in APP/PS1 after noise exposure, and used its pharmacological inhibitor to intervene to explore the mechanism by which CD36 affects APP/PS1 cognitive abilities. Our study shows that noise exposure has a more severe impact on the cognitive abilities of APP/PS1 mice, and that the expression trends of differentiation cluster molecules differ significantly between C57BL/6J and APP/PS1 mice. Transcriptomic analysis showed that the expression of CD36 in the hippocampus of APP/PS1 mice increased by 2.45-fold after noise exposure (p < 0.001). Meanwhile, Western Blot results from the hippocampus and entorhinal cortex indicated that CD36 protein levels increased by approximately 1.5-fold (p < 0.001) and 1.3-fold (p < 0.05) respectively, after noise exposure in APP/PS1 mice. The changes in CD36 expression elevated oxidative stress levels in the hippocampus and entorhinal cortex, leading to a decrease in PI3K/AKT phosphorylation, which in turn increased M1-type microglia and A1-type astrocytes while reducing the numbers of M2-type microglia and A2-type astrocytes. This increased neuroinflammation in the hippocampus and entorhinal cortex, causing synaptic and neuronal damage in APP/PS1 mice, ultimately exacerbating cognitive impairment. These findings may provide new insights into the relationship between noise exposure and cognitive impairment, especially given the different expression trends of CD molecules in the two types of mice, which warrants further research.

Circadian control of polycyclic aromatic hydrocarbon-induced dysregulation of endothelial tight junctions and mitochondrial bioenergetics

The study evaluates the impact of environmental toxicants, such as polycyclic aromatic hydrocarbons (PAHs), on circadian regulations and functions of brain endothelial cells, which form the main structural element of the blood-brain barrier (BBB). PAH are lipophilic and highly toxic environmental pollutants that accumulate in human and animal tissues. Environmental factors related to climate change, such as an increase in frequency and intensity of wildfires or enhanced strength of hurricanes or tropical cyclones, may lead to redistribution of these toxicants and enhanced human exposure. These natural disasters are also associated with disruption of circadian rhythms in affected populations, linking increased exposure to environmental toxicants to alterations of circadian rhythm pathways. Several vital physiological processes are coordinated by circadian rhythms, and disruption of the circadian clock can contribute to the development of several diseases. The blood-brain barrier (BBB) is crucial for protecting the brain from blood-borne harmful substances, and its integrity is influenced by circadian rhythms. Exposure of brain endothelial cells to a human and environmentally-relevant PAH mixture resulted in dose-dependent alterations of expression of critical circadian modulators, such as Clock, Bmal1, Cry1/2, and Per1/2. Moreover, silencing of the circadian Clock gene potentiated the impact of PAHs on the expression of the main tight junction genes and proteins (namely, claudin-5, occludin, JAM-2, and ZO-2), as well as mitochondrial bioenergetics. Findings from this study contribute to a better understanding of pathological influence of PAH-induced health effects, especially those related to circadian rhythm disruption.

LDHB-deficient brain exhibits resistance to ischemic neuronal cell death due to increased vasodilation

Ischemic stroke triggers a cascade of metabolic and inflammatory events leading to neuronal death, particularly in the hippocampus. Here, we investigate the role of lactate metabolism in ischemic resistance using LDHB-deficient mice, which exhibit impaired lactate utilization. Contrary to expectations of severe neuronal damage due to metabolic defects, LDHB-deficient mice displayed significantly increased neuronal survival following ischemic insult. Magnetic resonance spectroscopy revealed elevated lactate levels in LDHB-deficient brains, which correlated with enhanced vasodilation of the posterior communicating artery (PComA) and increased extracellular PGE2 levels. These findings suggest that elevated lactate inhibits PGE2 reabsorption, promoting vasodilation and neuronal protection. Our results highlight lactate's potential role in neuroprotection and its therapeutic promise for ischemic stroke.

Unveiling the role of astrogliosis in Alzheimer's disease Pathology: Insights into mechanisms and therapeutic approaches

Alzheimer's disease (AD) is one of the most debilitating age-related disorders that affect people globally. It impacts social and cognitive behavior of the individual and is characterized by phosphorylated tau and Aβ accumulation. Astrocytesmaintain a quiescent, anti-inflammatory state on anatomical level, expressing few cytokines and exhibit phagocytic activity to remove misfolded proteins. But in AD, in response to specific stimuli, astrocytes overstimulate their phagocytic character with overexpressing cytokine gene modules. Upon interaction with generated Aβ and neurofibrillary tangle, astrocytes that are continuously activated release a large number of inflammatory cytokines. This cytokine storm leads to neuroinflammation which is also one of the recognizable features of AD. Astrogliosis eventually promotes cholinergic dysfunction, calcium imbalance, oxidative stress and excitotoxicity. Furthermore, C5aR1, Lcn2/, BDNF/TrkB and PPARα/TFEB signaling dysregulation has a major impact on the disease progression. This review clarifies numerous ways that lead to astrogliosis, which is stimulated by a variety of processes that exacerbate AD pathology and make it a suitable target for AD treatment. Drugs under clinical and preclinical investigations that target several pathways managing astrogliosis and are efficacious in ameliorating the pathology of the disease are also included in this study. D-ALA2GIP, TRAM-34, Genistein, L-serine, MW150 and XPro1595 are examples of few drugs targeting astrogliosis. Therefore, this study may aid in the development of a potent therapeutic agent for ameliorating astrogliosis mediated AD progression.

Autophagy-dependent ferroptosis may play a critical role in early stages of diabetic retinopathy

Diabetic retinopathy (DR), as one of the most common and significant microvascular complications of diabetes mellitus (DM), continues to elude effective targeted treatment for vision loss despite ongoing enrichment of the under-standing of its pathogenic mechanisms from perspectives such as inflammation and oxidative stress. Recent studies have indicated that characteristic neuroglial degeneration induced by DM occurs before the onset of apparent microvascular lesions. In order to comprehensively grasp the early-stage pathological changes of DR, the retinal neurovascular unit (NVU) will become a crucial focal point for future research into the occurrence and progression of DR. Based on existing evidence, ferroptosis, a form of cell death regulated by processes like fer-ritinophagy and chaperone-mediated autophagy, mediates apoptosis in retinal NVU components, including pericytes and ganglion cells. Autophagy-dependent ferroptosis-related factors, including BECN1 and FABP4, may serve as both biomarkers for DR occurrence and development and potentially crucial targets for future effective DR treatments. The aforementioned findings present novel perspectives for comprehending the mechanisms underlying the early-stage pathological alterations in DR and open up innovative avenues for investigating supplementary therapeutic strategies.

Neuroimaging biomarkers for the diagnosis and prognosis of patients with disorders of consciousness

The progress in neuroimaging and electrophysiological techniques has shown substantial promise in improving the clinical assessment of disorders of consciousness (DOC). Through the examination of both stimulus-induced and spontaneous brain activity, numerous comprehensive investigations have explored variations in brain activity patterns among patients with DOC, yielding valuable insights for clinical diagnosis and prognostic purposes. Nonetheless, reaching a consensus on precise neuroimaging biomarkers for patients with DOC remains a challenge. Therefore, in this review, we begin by summarizing the empirical evidence related to neuroimaging biomarkers for DOC using various paradigms, including active, passive, and resting-state approaches, by employing task-based fMRI, resting-state fMRI (rs-fMRI), electroencephalography (EEG), and positron emission tomography (PET) techniques. Subsequently, we conducted a review of studies examining the neural correlates of consciousness in patients with DOC, with the findings holding potential value for the clinical application of DOC. Notably, previous research indicates that neuroimaging techniques have the potential to unveil covert awareness that conventional behavioral assessments might overlook. Furthermore, when integrated with various task paradigms or analytical approaches, this combination has the potential to significantly enhance the accuracy of both diagnosis and prognosis in DOC patients. Nonetheless, the stability of these neural biomarkers still needs additional validation, and future directions may entail integrating diagnostic and prognostic methods with big data and deep learning approaches.

Suppressing nuclear translocation of microglial PKM2 confers neuroprotection via downregulation of neuroinflammation after mouse cerebral ischemia-reperfusion injury

Pyruvate kinase M2 (PKM2) is a key metabolic enzyme. Yet, its role in cerebral ischemia injury remains unclear. In this study we demonstrated that PKM2 expression was increased in the microglia after mouse cerebral ischemia-reperfusion (I/R) injury. We found that microglial polarization-mediated pro-inflammatory effect was mediated by PKM2 after cerebral I/R. Mechanistically, our results revealed that nuclear PKM2 mediated ischemia-induced microglial polarization through association with acetyl-H3K9. Hif-1α mediated the effect of nuclear PKM2/histone H3 on microglial polarization. PKM2-dependent Histone H3/Hif-1α modifications contributed the expression of CCL2 and induced up-regulation of microglial polarization in peri-infarct, resulting in neuroinflammation. Inhibiting nuclear translocation of microglial PKM2 reduced ischemia-induced pro-inflammation and promoted neuronal survival. Together, this study identifies nucleus PKM2 as a crucial mediator for regulating ischemia-induced neuroinflammation, suggesting PKM2 as a potential therapeutic target in ischemic stroke.

HSP70 contributes to pathogenesis of fulminant hepatitis induced by coronavirus

Fulminant viral hepatitis (FH) represents a significant clinical challenge, with its pathogenesis not yet fully elucidated. Heat shock protein (HSP)70, a molecular chaperone protein with a broad range of cytoprotective functions, is upregulated in response to stress. However, the role of HSP70 in FH remains to be investigated. Notably, HSP70 expression is upregulated in the livers of coronavirus-infected mice and patients. Therefore, we investigated the mechanistic role of HSP70 in coronavirus-associated FH pathogenesis. FH was induced in HSP70-deficient (HSP70 KO) mice or in WT mice treated with the HSP70 inhibitor VER155008 when infected with the mouse hepatitis virus strain A59 (MHV-A59). MHV-A59-infected HSP70 KO mice exhibited significantly reduced liver damage and mortality. This effect was attributed to decreased infiltration of monocyte-macrophages and neutrophils in the liver of HSP70 KO mice, resulting in lower levels of inflammatory cytokines such as IL-1β, TNFα, and IL-6, and a reduced viral load. Moreover, treatment with the HSP70 inhibitor VER155008 protected mice from MHV-A59-induced liver damage and FH mortality. In summary, HSP70 promotes coronavirus-induced FH pathogenesis by enhancing the infiltration of monocyte-macrophages and neutrophils and promoting the secretion of inflammatory cytokines. Therefore, HSP70 is a potential therapeutic target in viral FH intervention.

AdipoRon exerts an antidepressant effect by inhibiting NLRP3 inflammasome activation in microglia via promoting mitophagy

Depression is a serious mental disorder that threatens patients' physical and mental health worldwide. The activation of the NLR family pyrin domain-containing 3 (NLRP3) inflammasome is essential for microglia-mediated neuroinflammation and neuronal damage in depression. Numerous pathophysiological factors, such as mitochondrial dysfunction and impaired mitophagy, have an essential role in activating the NLRP3 inflammasome. AdipoRon is a potent adiponectin receptor agonist; however, its antidepressant effects have not been thoroughly investigated. In this study, we found that AdipoRon ameliorated depression-like behavior and neuronal damage induced by chronic unpredictable mild stress (CUMS). Further research demonstrated that AdipoRon inhibited the activation of the NLRP3 inflammasome and protected hippocampal neurons from microglial cytotoxicity by promoting mitophagy, increasing the clearance of damaged mitochondria, and reducing mtROS accumulation. Importantly, inhibition of mitophagy attenuated the antidepressant and neuroprotective effects of AdipoRon. Overall, these findings indicate that AdipoRon alleviates depression by inhibiting NLRP3 inflammasome activation in microglia via improving mitophagy.

Metformin attenuates white matter injury in neonatal mice through activating NRF2/HO-1/NF-κB pathway

White matter injury (WMI) is a major form of brain injury that occurs in preterm infants and develops into lifelong disabilities, including cerebral palsy, impaired cognitive function, and psychiatric disorders. Metformin (MET) has been reported to have neuroprotective effects. However, whether MET is responsible for neuroprotection against WMI remains unclear. In this study, we established a WMI model in neonatal mice to explore the neuroprotective effects of MET and attempted to elucidate its potential mechanisms. Our results showed that MET increased the expression of myelin basic protein (MBP), oligodendrocyte transcription factor 2 (Olig2), and CC1, improved the thickness and density of the myelin sheath, and reduced oxidative stress and microglial infiltration after chronic hypoxia induction. Moreover, MET improved memory, learning, and motor abilities as well as relieved anxiety-like behaviors in mice with WMI. These protective effects of MET may involve the upregulation of the nuclear factor erythroid 2-related factor 2 (NRF2)/heme oxygenase-1(HO-1)/NF-κB pathway related protein expressions. In addition, the NRF2 inhibitor ML385 could significantly reverse the effects of MET. In conclusion, this study suggested that MET attenuated chronic hypoxia-induced WMI through activating the NRF2/HO-1/NF-κB pathway, indicating that MET might be a promising therapeutic option for WMI.

The piper at the gates of brain: A systematic review of surface modification strategies on lipid nanoparticles to overcome the Blood-Brain-Barrier

The Blood-Brain Barrier (BBB) significantly impedes drug delivery to the central nervous system. Nanotechnology, especially surface-functionalized lipid nanoparticles, offers innovative approaches to overcome this barrier. However, choosing an effective functionalization strategy is challenging due to the lack of detailed comparative analysis in current literature. Our systematic review examined various functionalization strategies and their impact on BBB permeability from 2041 identified articles, of which 80 were included for data extraction. Peptides were the most common modification (18) followed by mixed strategies (12) proteins (9), antibodies (7), and other strategies (8). Interestingly, 26 studies showed BBB penetration with unmodified or modified nanoparticles using commonly applied strategies such as PEGylation or surfactant addition. Statistical analysis across 42 studies showed correlation between higher in vivo permeation improvements and nanoparticle type, size, and functionalization category. The highest ratios were found for nanostructured lipid carriers or biomimetic systems, in studies with particle sizes under 150 nm, and in those applying mixed functionalization strategies. The interstudy heterogeneity we observed highlights the importance of adopting standardized evaluation protocols to enhance comparability. Our systematic review aims to provide a comparative insight and identify future research directions in the development of more effective lipid nanoparticle systems for drug delivery to the brain to help improve the treatment of neurological and psychiatric disorders and brain tumours.

α7nAChR-mediated astrocytic activation: A novel mechanism of Xiongzhi Dilong decoction in ameliorating chronic migraine

ETHNOPHARMACOLOGICAL RELEVANCE

Alpha 7 nicotinic acetylcholine receptor (α7nAChR)-mediated astrocytic activation is closely related to central sensitization of chronic migraine (CM). Xiongzhi Dilong decoction (XZDL), originated from Xiongzhi Shigao decoction of Yi-zong-jin-jian, has been confirmed to relieve CM in experiment and clinic. However, its underlying mechanism for treating CM has not been elucidated.

AIM OF THE STUDY

To reveal the underlying mechanisms of XZDL to alleviate CM in vivo focusing mainly on α7nAChR-mediated astrocytic activation and central sensitization in TNC.

MATERIALS AND METHODS

CM rat model was established by subcutaneous injection of nitroglycerin (NTG) recurrently, and treated with XZDL simultaneously. Migraine-like behaviors of rats (ear redness, head scratching, and cage climbing) and pain-related reactions (mechanical hind-paw withdrawal threshold) of rats were evaluated before and after NTG injection and XZDL administration at different points in time for nine days. The immunofluorescence single and double staining were applied to detect the levels of CGRP, c-Fos, GFAP and α7nAChR in NTG-induced CM rats. ELISA kits were employed to quantify levels of TNF-α, IL-1β, and IL-6 in medulla oblongata of CM rats. The expression levels of target proteins were examined using western blotting. Finally, methyllycaconitine citrate (MLA, a specific antagonist of α7nAChR) was applied to further validate the mechanisms of XZDL in vivo.

RESULTS

XZDL significantly attenuated the pain-related behaviors of the NTG-induced CM rats, manifesting as constraints of aberrant migraine-like behaviors including elongated latency of ear redness and decreased numbers of head scratching and cage climbing, and increment of mechanical withdrawal threshold. Moreover, XZDL markedly lowered levels of CGRP and c-Fos, as well as inflammatory cytokines (IL-1β, IL-6 and TNF-α) in CM rats. Furthermore, XZDL significantly enhanced α7nAChR expression and its co-localization with GFAP, while markedly inhibited the expression of GFAP and the activation of JAK2/STAT3/NF-κB pathway in the TNC of CM rats. Finally, blocking α7nAChR with MLA reversed the effects of XZDL on astrocytic activation, central sensitization, and the pain-related behaviors in vivo.

CONCLUSION

XZDL inhibited astrocytic activation and central sensitization in NTG-induced CM rats by facilitating α7nAChR expression and suppressing JAK2/STAT3/NF-κB pathway, implying that the regulation of α7nAChR-mediated astrocytic activation represents a novel mechanism of XZDL for relieving CM.

Erianin alleviates cerebral ischemia-reperfusion injury by inhibiting microglial cell polarization and inflammation via the PI3K/AKT and NF-κB pathways

Cerebral ischemia-reperfusion injury (CI/RI) is a leading cause of disability and mortality worldwide, with limited therapeutic options available. Erianin, a natural compound derived from traditional Chinese medicine, has been reported to possess anti-inflammatory and neuroprotective properties. This study aimed to investigate the therapeutic potential of Erianin in CI/RI and elucidate its underlying mechanisms. Network pharmacology analysis predicted that Erianin could target the PI3K/AKT pathway, which are closely associated with CI/RI. In vivo experiments using a rat model of CI/RI demonstrated that Erianin treatment significantly alleviated neurological deficits, reduced infarct volume, and attenuated neuronal damage. Mechanistically, Erianin inhibited microglial cell polarization towards the pro-inflammatory M1 phenotype, as evidenced by the modulation of specific markers. Furthermore, Erianin suppressed the expression of pro-inflammatory cytokines and mediators, such as TNF-α, IL-6, and COX-2, while enhancing the production of anti-inflammatory factors, including Arg1, CD206, IL-4 and IL-10. In vitro studies using oxygen-glucose deprivation/reoxygenation (OGD/R)-stimulated microglial cells corroborated the anti-inflammatory and anti-apoptotic effects of Erianin. Notably, Erianin inhibited the NF-κB signaling pathway by inhibiting p65 phosphorylation and preventing the nuclear translocation of the p65 subunit. Collectively, these findings suggest that Erianin represents a promising therapeutic candidate for CI/RI by targeting microglial cell polarization and inflammation.

Nephroprotective effects of hyperbaric oxygen therapy in murine models of acute kidney injury: A systematic review and meta-analysis

AIMS

Acute kidney injury (AKI) is a life-threatening condition marked by sudden kidney function loss and azotemia. While its management is limited to supportive care, the effects of hyperbaric oxygen therapy (HBO) on AKI remain a subject of conflicting animal research. This study aimed to systematically review and meta-analyze HBO's effects on renal function biomarkers serum creatinine (SCr) and blood urea nitrogen (BUN) in murine AKI models, also exploring tissue-level nephroprotection.

MAIN METHODS

The PUBMED, SciELO, and LILACS databases were searched until September 5, 2024. Effect sizes of HBO on SCr and BUN levels were expressed as standardized mean difference (SMD) alongside 95 % confidence interval (CI), calculated by random-effects model. Extracted data also included murine specie/strain, HBO parameters, AKI induction method (toxic, ischemic, others), and histological findings. Study quality and publication bias were respectively assessed using the CAMARADES checklist and Egger's test. This review adhered to PRISMA guidelines and was registered in PROSPERO (CRD42022369804).

KEY FINDINGS

Data synthesis from 21 studies demonstrates that HBO effectively reduces azotemia in AKI-affected animals (SCr's SMD = -1.69, 95 % CI = -2.38 to -0.99, P < 0.001; BUN's SMD = -1.51, 95 % CI = -2.32 to -0.71, P < 0.001) while mitigating histological damage. Subgroup analyses indicate that HBO particularly benefits ischemic and other AKI types (P < 0.05). In contrast, data from toxic AKI models were inconclusive due to insufficient statistical power (P > 0.05, 1-β < 30 %).

SIGNIFICANCE

This meta-analysis provides compelling evidence supporting the adjunctive use of HBO in AKI management.

Pervasive expostulation of p53 gene promoting the precipitation of neurogenic convulsions: A journey in therapeutic advancements

Epilepsy, a neurological disorder characterized by prolonged and excessive seizures, has been linked to elevated levels of the tumor suppressor gene p53, which contributes to neuronal dysfunction. This review explores the molecular mechanisms of p53 in epilepsy and discusses potential future therapeutic strategies. Research indicates that changes in p53 expression during neuronal apoptosis, neuroinflammation, and oxidative stress play a significant role in the pathogenesis of epilepsy. Elevated p53 disrupts glutamatergic neurotransmission and hyperactivates NMDA and AMPA receptors, leading to increased neuronal calcium influx, mitochondrial oxidative stress, and activation of apoptotic pathways mediated neuronal dysfunction, exacerbating epileptogenesis. The involvement of p53 in epilepsy suggests that targeting this protein could be beneficial in mitigating neuronal damage and preventing seizure recurrence. Pharmacological agents like pifithrin-α have shown promise in reducing p53-mediated apoptosis and seizure severity. Gene therapy approaches, such as viral vector-mediated delivery of wild-type p53 or RNA interference targeting mutant p53, have also been effective in restoring normal p53 function and reducing seizure susceptibility. Despite these advances, the heterogeneous nature of epilepsy and potential long-term side effects of p53 modulation present challenges. Future research should focus on elucidating the precise molecular mechanisms of p53 and developing personalized therapeutic strategies. Modulating p53 activity holds promise for reducing seizure susceptibility and improving the quality of life for individuals with epilepsy. The current review provides the understanding the intricate role of p53 in neuroinflammatory pathways, including JAK-STAT, JNK, NF-κB, Sonic Hedgehog, and Wnt, is crucial for developing targeted therapies.

Abnormal hippocampal neurogenesis and impaired social recognition memory in two neurodevelopmental models of schizophrenia

Schizophrenia is a mental disorder characterized by cognitive impairments, specifically deficits in social recognition memory (SRM). Abnormal hippocampal neurogenesis has been implicated in these deficits. Due to the pathogenetic heterogeneity of schizophrenia, studying the hippocampal neurogenesis and SRM in two models with prenatal and postnatal defects could enhance our understanding of the developmental aspects of the biological susceptibility to schizophrenia. Here, we examined SRM and hippocampal neurogenesis in two developmental models of schizophrenia: gestational exposure to methylazoxymethanol acetate (MAM) and postweaning social isolation (SI). Our findings revealed that gestational MAM exposure induced a decay of social memory while postweaning SI led to impaired social memory formation and decay. In both models, we observed a correlation between impaired SRM and reduced number, and abnormal differentiation and less complex morphology of hippocampal neurons. These results indicate that aberrant hippocampal neurogenesis may contribute to the deficits of SRM in both models, and these abnormalities may be a shared underlying pathogenic factor in developmental models of schizophrenia, regardless of prenatal and postnatal pathogenesis.

Exploration of the shared diagnostic genes and mechanisms between periodontitis and primary Sjögren's syndrome by integrated comprehensive bioinformatics analysis and machine learning

BACKGROUND

Accumulating evidence has showed a bidirectional link between periodontitis (PD) and primary Sjögren's syndrome (pSS), but the mechanisms of their occurrence remain unclear. Hence, this study aimed to investigate the shared diagnostic genes and potential mechanisms between PD and pSS using bioinformatics methods.

METHODS

Gene expression data for PD and pSS were acquired from the Gene Expression Omnibus (GEO) database. Differential expression genes (DEGs) analysis and weighted gene co-expression network analysis (WGCNA) were utilized to search common genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were conducted to explore biological functions. Three machine learning algorithms (least absolute shrinkage and selection operator (LASSO), support vector machine recursive feature elimination (SVM-RFE), and random forest (RF)) were used to further identify shared diagnostic genes, and these genes were assessed via receiver operating characteristic (ROC) curves in discovery and validation datasets. CIBERSORT was employed for immune cell infiltration analysis. Transcription factors (TFs)-genes and miRNAs-genes regulatory networks were conducted by NetworkAnalyst. Finally, relevant drug targets were predicted by DSigDB.

RESULTS

Based on DEGs, 173 overlapping genes were obtained and primarily enriched in immune- and inflammation-related pathways. WGCNA revealed 34 common disease-related genes, which were enriched in similar biological pathways. Intersecting the DEGs with WGCNA results yielded 22 candidate genes. Moreover, three machine learning algorithms identified three shared genes (CSF2RB, CXCR4, and LYN) between PD and pSS, and these genes demonstrated good diagnostic performance (AUC>0.85) in both discovery and validation datasets. The immune cell infiltration analysis showed significant dysregulation in several immune cell populations. Regulatory network analysis highlighted that WRNIP1 and has-mir-155-5p might be pivotal co-regulators of the three shared gene expressions. Finally, the top 10 potential gene-targeted drugs were screened.

CONCLUSION

CSF2RB, CXCR4, and LYN may serve as potential biomarkers for the concurrent diagnosis of PD and pSS. Additionally, we identified common molecular mechanisms, TFs, miRNAs, and candidate drugs between PD and pSS, which may provide novel insights and targets for future research on the pathogenesis, diagnosis, and therapy of both diseases.

Ginsenoside Rg1 regulates astrocytes to promote angiogenesis in spinal cord injury via the JAK2/STAT3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ginseng (Panax ginseng C. A. Mey) is a common traditional Chinese medicine used for anti-inflammation, anti-apoptosis, anti-oxidative stress, and neuroprotection. Ginsenosides Rg1, the main active components isolated from ginseng, may be a feasible therapy for spinal cord injury (SCI).

AIMS OF THE STUDY

SCI causes endothelial cell death and blood vessel rupture, ultimately resulting in long-term neurological impairment. As a result, encouraging spinal angiogenesis may be a feasible therapy for SCI. This investigation aimed to validate the capacity of ginsenoside Rg1 in stimulating angiogenesis within the spinal cord.

MATERIALS AND METHODS

Rats with SCI were injected intraperitoneally with ginsenoside Rg1. The effectiveness of ginsenoside Rg1 was assessed using the motor function score and the motor-evoked potential (MEP). Immunofluorescence techniques were applied to identify the spinal cord's angiogenesis. Angiogenic factors were examined through Western Blot (WB) and Immunohistochemistry. Oxygen-glucose deprivation (OGD) was employed to establish the hypoxia-ischemia model in vitro, and astrocytes (As) were given ginsenoside Rg1 and co-cultured with spinal cord microvascular endothelial cells (SCMECs). Immunofluorescence, wound healing test, and tube formation assay were used to identify the co-cultured SCMECs' activity. Finally, network pharmacology analysis and siRNA transfection were applied to verify the mechanism of ginsenoside Rg1 promoting angiogenesis.

RESULTS

The rats with SCI treated with ginsenoside Rg1 indicated more significant functional recovery, more pronounced angiogenesis, and higher levels of angiogenic factor expression. In vitro, the co-culture system with ginsenoside Rg1 intervention improved SCMECs' capacity for proliferating, migrating, and forming tubes, possibly by promoting the expression of vascular endothelial growth factor (VEGF) in As via the janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway.

CONCLUSION

Ginsenoside Rg1 can regulate As to promote angiogenesis, which may help to understand the mechanism of promoting SCI recovery.