The role of inflammasomes in vascular cognitive impairment

ChemR23 activation attenuates cognitive impairment in chronic cerebral hypoperfusion by inhibiting NLRP3 inflammasome-induced neuronal pyroptosis

Neuroinflammation plays critical roles in vascular dementia (VaD), the second leading cause of dementia, which can be induced by chronic cerebral hypoperfusion (CCH). NLRP3 inflammasome-induced pyroptosis, the inflammatory programmed cell death, has been reported to contribute to the development of VaD. ChemR23 is a G protein-coupled receptor that has emerging roles in regulating inflammation. However, the role of ChemR23 signalling in NLRP3 inflammasome-induced pyroptosis in CCH remains elusive. In this study, a CCH rat model was established by permanent bilateral common carotid artery occlusion (BCCAO) surgery. Eight weeks after the surgery, the rats were intraperitoneally injected with the ChemR23 agonist Resolvin E1 (RvE1) or chemerin-9 (C-9). Additionally, primary rat hippocampal neurons and SH-SY5Y cells were adopted to mimic CCH injury in vitro. Our results showed that the levels of ChemR23 expression were decreased from the 8th week after BCCAO, accompanied by significant cognitive impairment. Further analysis revealed that CCH induced neuronal damage, synaptic injury and NLRP3-related pyroptosis activation in hippocampal neurons. However, pharmacologic activation of ChemR23 with RvE1 or C-9 counteracted these changes. In vitro experiments also showed that ChemR23 activation prevented primary neuron pyroptosis induced by chronic hypoxia. In addition, manipulating ChemR23 expression markedly regulated NLRP3 inflammasome-induced neuronal pyroptosis through PI3K/AKT/Nrf2 signalling in SH-SY5Y cells under hypoglycaemic and hypoxic conditions. Collectively, our data demonstrated that ChemR23 activation inhibits NLRP3 inflammasome-induced neuronal pyroptosis and improves cognitive function via the PI3K/AKT/Nrf2 signalling pathway in CCH models. ChemR23 may serve as a potential novel therapeutic target to treat CCH-induced cognitive impairment.

NLRP3 inflammasome in cognitive impairment and pharmacological properties of its inhibitors

Cognitive impairment is a multifactorial and multi-step pathological process that places a heavy burden on patients and the society. Neuroinflammation is one of the main factors leading to cognitive impairment. The inflammasomes are multi-protein complexes that respond to various microorganisms and endogenous danger signals, helping to initiate innate protective responses in inflammatory diseases. NLRP3 inflammasomes produce proinflammatory cytokines (interleukin IL-1β and IL-18) by activating caspase-1. In this review, we comprehensively describe the structure and functions of the NLRP3 inflammasome. We also explore the intrinsic relationship between the NLRP3 inflammasome and cognitive impairment, which involves immune cell activation, cell apoptosis, oxidative stress, mitochondrial autophagy, and neuroinflammation. Finally, we describe NLRP3 inflammasome antagonists as targeted therapies to improve cognitive impairment.

Anti-inflammatory effect and mechanism of catalpol in various inflammatory diseases

Catalpol is a kind of iridoid glucoside, widely found in a variety of plants, mostly extracted from the rhizome of the traditional medicinal herb rehmanniae. It has various biological activities such as anti-inflammatory, antioxidant, and antitumor. The anti-inflammatory effects of catalpol have been demonstrated in a variety of diseases, such as neurological diseases, atherosclerosis, renal diseases, respiratory diseases, digestive diseases, bone and joint diseases, eye diseases, and periodontitis. The purpose of this review is to summarize the existing literature on the anti-inflammatory effects of catalpol in a variety of inflammatory diseases over the last decade and to focus on the anti-inflammatory mechanisms of catalpol.

Inflammasomes in human reproductive diseases

Inflammasomes are multi-protein complexes localized within immune and non-immune cells that induce caspase activation, proinflammatory cytokine secretion, and ultimately pyroptosis-a type of cell death. Inflammasomes are involved in a variety of human diseases, especially acute or chronic inflammatory diseases. In this review, we focused on the strong correlation between the NLRP3 inflammasome and various reproductive diseases, including ovarian aging or premature ovarian insufficiency, PCOS, endometriosis, recurrent spontaneous abortion, preterm labor, pre-eclampsia, and male subfertility, as well as the multifaceted role of NLRP3 in the pathogenesis and treatment of these diseases. In addition, we provide an overview of the structure and amplification of inflammasomes. This comprehensive review demonstrates the vital role of NLRP3 inflammasome activation in human reproductive diseases together with the underlying mechanisms, offers new insights for mechanistic studies of reproduction, and provides promising possibilities for the development of drugs targeting the NLRP3 inflammasome for the treatment of reproductive disorders in the future.

Bioinformatics Analysis and Experimental Verification of Exercise for Aging Mice in Different Brain Regions Based on Transcriptome Sequencing

PURPOSE

Physical exercise mitigates the effects of aging and cognitive decline. However, the precise neurobiological mechanisms underlying this phenomenon remain unclear. The primary aim of this study was to investigate the protective effect of exercise on age-related memory deficits in the prefrontal cortex (PFC) and hippocampus using bioinformatic analysis and biochemical verification.

METHODS

Young and aging mice were subjected to natural feeding or treadmill exercise (12 m/min, 8 weeks). Cognitive function was accessed using the Barnes maze and novel object recognition. Bioinformatic analysis was performed to identify co-expressed genes in different groups and brain regions. The selected genes and pathways were validated using RT-qPCR.

RESULTS

Regular exercise significantly ameliorated age-related cognitive deficits. Four up-regulated targets (Ifi27l2a, Irf7, Oas1b, Ifit1) and one down-regulation (Septin2) were reversed by exercise, demonstrating the underlying mechanisms of cognitive functions induced by aging with exercise in the hippocampus and PFC. The Gene Ontology terms and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses indicated that the NOD-like receptor signaling pathway was inhibited in the neuroinflammation effects of exercise in aging mice in both brain regions.

CONCLUSION

Exercise enhances age-related learning and memory deficits. This beneficial effect may be attributed to the changes in five up/down-regulated genes and the NOD-like receptor signaling pathway in both the hippocampus and PFC. These findings establish the modulation of neuroinflammation as a pivotal molecular mechanism supporting exercise intervention in the brain aging process.

Neuroprotective effect of 20 (S) - Protopanaxadiol (PPD) attenuates NLRP3 inflammasome-mediated microglial pyroptosis in vascular dementia rats

20(S)-protopanaxadiol (PPD), one of the ginsenosides from Panax ginseng, has been reported to improve performance with dementia. This study aimed to investigate the neuroprotective effect of PPD attenuating NLRP3 inflammasome-mediated microglial pyroptosis in vascular dementia (VD) rats induced by bilateral common carotid artery ligation (2-VO). Male Sprague-Dawley rats (SPF, 150-180 g, n = 10/group) were randomly divided into PPD (20, 10, 5 mg/kg, subcutaneous injection once per day for 3 weeks), model, and vehicle-sham group. It was found that PPD significantly reversed 2-VO-induced cognitive impairment by decreasing escape latency and spontaneous alternation and increasing the number of crossing platforms, showing memory-improving effects. PPD improved the pathological morphology of brain tissue in VD rats. PPD significantly reduced the cerebral infarction area and the activation of microglia in the cortex and hippocampal DG, CA1, and CA3 area. Moreover, PPD could attenuate NLRP3 inflammasome-mediated microglial pyroptosis, inhibit the positive expression of NLRP3, decrease IL-1β, and IL-18 levels, and increase IL-10 levels in the brain cortex. PPD also significantly alleviated the neurotoxicity by decreasing the Aβ and p-Tau in hippocampal DG, CA1, and CA3 areas. In addition, the levels of NLRP3, ASC, and IL-1β in the cortex, APP, BACE1, and p-Tau in the hippocampus were significantly reduced by PPD. These results suggested that PPD hinders microglial activation to alleviate neuroinflammation of NLRP3 inflammasome and inhibits neurotoxicity of Aβ deposition and Tau phosphorylation in 2-VO-induced VD rats.

Prevotella histicola Transplantation Ameliorates Cognitive Impairment and Decreases Oxidative Stress in Vascular Dementia Rats

Vascular dementia is a type of dementia from brain damage caused by cerebrovascular lesions and vascular risk factors. Prevotella histicola is a species of Prevotella, belonging to the category of obligate anaerobe. The purpose of our work was to study the protection of Prevotella histicola on cognitive function in rats subjected to vascular dementia (VaD) and investigate underlying molecular mechanisms. The rats were randomly divided into three groups: control group, 2VO group and 2VO + Prevotella histicola group. The VaD rats (the 2VO group and 2VO + Prevotella histicola group) were generated by bilateral common carotid artery occlusion (2VO). Rats in the 2VO+ Prevotella histicola group were administered with Prevotella histicola twice daily. In comparison with the rats in the 2VO group, rats in the 2VO + Prevotella histicola group presented an enhanced cognitive ability, increased synapse-associated protein expression, a downregulation of proinflammatory factors and an upregulation of neurotrophic factors. The relevant mechanism of the protective effect of Prevotella histicola may be associated with the inhibition of glial cell-associated inflammation by regulating phosphorylation of CaMKII. In conclusion, Prevotella histicola attenuates neurological impairments via regulating synapse-associated protein expression and the liberation of inflammatory elements in vascular dementia rats. The findings above might benefit the development of Prevotella histicola transplantation as a promising treatment of VaD.

Sex differences in the effects of high fat diet on underlying neuropathology in a mouse model of VCID

BACKGROUND

Damage to the cerebral vasculature can lead to vascular contributions to cognitive impairment and dementia (VCID). A reduction in blood flow to the brain leads to neuropathology, including neuroinflammation and white matter lesions that are a hallmark of VCID. Mid-life metabolic disease (obesity, prediabetes, or diabetes) is a risk factor for VCID which may be sex-dependent (female bias).

METHODS

We compared the effects of mid-life metabolic disease between males and females in a chronic cerebral hypoperfusion mouse model of VCID. C57BL/6J mice were fed a control or high fat (HF) diet starting at ~ 8.5 months of age. Three months after diet initiation, sham or unilateral carotid artery occlusion surgery (VCID model) was performed. Three months later, mice underwent behavior testing and brains were collected to assess pathology.

RESULTS

We have previously shown that in this VCID model, HF diet causes greater metabolic impairment and a wider array of cognitive deficits in females compared to males. Here, we report on sex differences in the underlying neuropathology, specifically white matter changes and neuroinflammation in several areas of the brain. White matter was negatively impacted by VCID in males and HF diet in females, with greater metabolic impairment correlating with less myelin markers in females only. High fat diet led to an increase in microglia activation in males but not in females. Further, HF diet led to a decrease in proinflammatory cytokines and pro-resolving mediator mRNA expression in females but not males.

CONCLUSIONS

The current study adds to our understanding of sex differences in underlying neuropathology of VCID in the presence of a common risk factor (obesity/prediabetes). This information is crucial for the development of effective, sex-specific therapeutic interventions for VCID.

Enriched environment attenuates hippocampal theta and gamma rhythms dysfunction in chronic cerebral hypoperfusion via improving imbalanced neural afferent levels

Chronic cerebral hypoperfusion (CCH) is increasingly recognized as a common cognitive impairment-causing mechanism. However, no clinically effective drugs to treat cognitive impairment due to CCH have been identified. An abnormal distribution of neural oscillations was found in the hippocampus of CCH rats. By releasing various neurotransmitters, distinct afferent fibers in the hippocampus influence neuronal oscillations in the hippocampus. Enriched environments (EE) are known to improve cognitive levels by modulating neurotransmitter homeostasis. Using EE as an intervention, we examined the levels of three classical neurotransmitters and the dynamics of neural oscillations in the hippocampus of the CCH rat model. The results showed that EE significantly improved the balance of three classical neurotransmitters (acetylcholine, glutamate, and GABA) in the hippocampus, enhanced the strength of theta and slow-gamma (SG) rhythms, and dramatically improved neural coupling across frequency bands in CCH rats. Furthermore, the expression of the three neurotransmitter vesicular transporters-vesicular acetylcholine transporters (VAChT) and vesicular GABA transporters (VGAT)-was significantly reduced in CCH rats, whereas the expression of vesicular glutamate transporter 1 (VGLUT1) was abnormally elevated. EE partially restored the expression of the three protein levels to maintain the balance of hippocampal afferent neurotransmitters. More importantly, causal mediation analysis showed EE increased the power of theta rhythm by increasing the level of VAChT and VGAT, which then enhanced the phase amplitude coupling of theta-SG and finally led to an improvement in the cognitive level of CCH. These findings shed light on the role of CCH in the disruption of hippocampal afferent neurotransmitter balance and neural oscillations. This study has implications for our knowledge of disease pathways.

Chronic cerebral hypoperfusion alters the CypA-EMMPRIN-gelatinase pathway: Implications for vascular dementia

Chronic cerebral hypoperfusion (CCH) is postulated to underlie multiple pathophysiological processes in vascular dementia (VaD), including extracellular matrix dysfunction. While several extracellular matrix proteins, namely cyclophilin A (CypA), extracellular matrix metalloproteinase inducer (EMMPRIN) and gelatinases (matrix metalloproteinases, MMP-2 and -9) have been investigated in acute stroke, their involvement in CCH and VaD remains unclear. In this study, CypA-EMMPRIN-gelatinase proteins were analysed in a clinical cohort of 36 aged, cognitively unimpaired subjects and 48 VaD patients, as well as in a bilateral carotid artery stenosis mouse model of CCH. Lower CypA and higher EMMPRIN levels were found in both VaD serum and CCH mouse brain. Furthermore, gelatinases were differentially altered in CCH mice and VaD patients, with significant MMP-2 increase in CCH brain and serum, whilst serum MMP-9 was elevated in VaD but reduced in CCH, suggesting complex CypA-EMMPRIN-gelatinase regulatory mechanisms. Interestingly, subjects with cortical infarcts had higher serum MMP-2, while white matter hyperintensities, cortical infarcts and lacunes were associated with higher serum MMP-9. Taken together, our data indicate that perturbations of CypA-EMMPRIN signalling may be associated with gelatinase-mediated vascular sequelae, highlighting the potential utility of the CypA-EMMPRIN-gelatinase pathway as clinical biomarkers and therapeutic targets in VaD.

NLRP3 Inflammasome: A key contributor to the inflammation formation

Inflammation is an important part of the development of various organ diseases. The inflammasome, as an innate immune receptor, plays an important role in the formation of inflammation. Among various inflammasomes, the NLRP3 inflammasome is the most well studied. The NLRP3 inflammasome is composed of skeletal protein NLRP3, apoptosis-associated speck-like protein (ASC) and pro-caspase-1. There are three types of activation pathways: (1) "classical" activation pathway; (2) "non-canonical" activation pathway; (3) "alternative" activation pathway. The activation of NLRP3 inflammasome is involved in many inflammatory diseases. A variety of factors (such as genetic factors, environmental factors, chemical factors, viral infection, etc.) have been proved to activate NLRP3 inflammasome and promote the inflammatory response of the lung, heart, liver, kidney and other organs in the body. Especially, the mechanism of NLRP3 inflammation and its related molecules in its associated diseases remains not to be summarized, namely they may promote or delay inflammatory diseases in different cells and tissues. This article reviews the structure and function of the NLRP3 inflammasome and its role in various inflammations, including inflammations caused by chemically toxic substances.

Analysis of Potential Mechanism of Herbal Formula Taohong Siwu Decoction against Vascular Dementia Based on Network Pharmacology and Molecular Docking

Vascular dementia (VaD) is the second most prevalent dementia, which is attributable to neurovascular dysfunction. Currently, no approved pharmaceuticals are available. Taohong Siwu decoction (TSD) is a traditional Chinese medicine prescription with powerful antiapoptosis and anti-inflammatory properties. In this study, a network pharmacology approach together with molecular docking validation was used to explore the probable mechanism of action of TSD against VaD. A total of 44 active components, 202 potential targets of components, and 3,613 VaD-related targets including 161 intersecting were obtained. The potential chemical components including kaempferol, baicalein, beta-carotene, luteolin, quercetin, and beta-sitosterol involved in the inflammatory response, oxidative stress, and apoptosis might have potential therapeutic effects on the treatment of VaD. The potential core targets including AKT1, CASP3, IL1β, JUN, and TP53 associated with cell apoptosis and inflammatory might account for the essential therapeutic effects of TSD in VaD. The results indicated that TSD protected against VaD through multicomponent and multitarget modes. Though the detailed mechanism of action of various active ingredients needs to be further illustrated, TSD still showed a promising therapeutic agent for VaD due to its biological activity.

Brain atrophy and white matter hyperintensities are independently associated with plasma neurofilament light chain in an Asian cohort of cognitively impaired patients with concomitant cerebral small vessel disease

Introduction

Plasma neurofilament light chain (NfL) is a potential biomarker for neurodegeneration in Alzheimer's disease (AD), ischemic stroke, and non-dementia cohorts with cerebral small vessel disease (CSVD). However, studies of AD in populations with high prevalence of concomitant CSVD to evaluate associations of brain atrophy, CSVD, and amyloid beta (Aβ) burden on plasma NfL are lacking.

Methods

Associations were tested between plasma NfL and brain Aβ, medial temporal lobe atrophy (MTA) as well as neuroimaging features of CSVD, including white matter hyperintensities (WMH), lacunes, and cerebral microbleeds.

Results

We found that participants with either MTA (defined as MTA score ≥2; neurodegeneration [N]+WMH-) or WMH (cut-off for log-transformed WMH volume at 50th percentile; N-WMH+) manifested increased plasma NfL levels. Participants with both pathologies (N+WMH+) showed the highest NfL compared to N+WMH-, N-WMH+, and N-WMH- individuals.

Discussion

Plasma NfL has potential utility in stratifying individual and combined contributions of AD pathology and CSVD to cognitive impairment.

Correlations among peripheral blood markers, white matter hyperintensity, and cognitive function in patients with non-disabling ischemic cerebrovascular events

BACKGROUND

Both inflammation and cerebral white matter injury are closely associated with vascular cognitive impairment (VCI). The aim of this study was to analyze the correlation between peripheral serological markers, white matter injury, and cognitive function in patients with non-disabling ischemic cerebrovascular events (NICE); to identify potential biological markers for the diagnosis and prediction of VCI; and to provide a basis for the early diagnosis and intervention of VCI.

METHODS

We collected clinical data, along with demographic and medical history data, from 151 NICE patients. Fasting venous blood samples were collected. Based on the Montreal Cognitive Assessment (MoCA) after admission, we divided the patients into normal cognitive function (NCF) and VCI groups, and then classified them into mild white matter hyperintensity (mWMH) and severe white matter hyperintensity (sWMH) based on Fazekas scores. The differences in serological marker levels were compared between the cognitive function groups and the white matter hyperintensity groups. Binary logistic regression models and receiver operating characteristic curves were used to analyze the diagnostic predictive value of serological markers for VCI in patients with NICE and in the white matter hyperintensity subgroups.

RESULTS

Among 151 patients with NICE, 95 were male and 56 were female. Lymphocyte count (OR = 0.405, p = 0.010, 95% CI [0.201, 0.806]), red blood cell count (OR = 0.433, p = 0.010, 95% CI [0.228, 0.821]), and hemoglobin level (OR = 0.979, p = 0.046, 95% CI [0.958, 0.999]) were protective factors for cognitive function in patients with NICE. The sWMH group had a higher age, granulocyte/lymphoid ratio (NLR), and neutrophil percentage but a lower MoCA score, hemoglobin level, and lymphocyte count than the mWMH group. In the mWMH group, lymphocyte count (AUC = 0.713, p = 0.003, 95% CI [0.593, 0.833]) had an acceptable predictive value for the diagnosis of VCI, whereas white blood cell count (AUC = 0.672, p = 0.011, 95% CI [0.545, 0.799]), red blood cell count (AUC = 0.665, p = 0.014, 95% CI [0.545, 0.784]), and hemoglobin level (AUC = 0.634, p = 0.047, 95% CI [0.502, 0.765]) had marginal predictive value for the diagnosis of VCI. In the sWMH group, no significant differences were found in serological markers between the NCF and VCI groups.

CONCLUSION

Lymphocyte count, red blood cell count, and hemoglobin level were independent protective factors for cognitive function in patients with NICE; they can be used as potential biological markers to distinguish VCI in patients with NICE and are applicable to subgroups of patients with mWMH.

Physiological and Pathological Remodeling of Cerebral Microvessels

There is growing evidence that the remodeling of cerebral microvessels plays an important role in plastic changes in the brain associated with development, experience, learning, and memory consolidation. At the same time, abnormal neoangiogenesis, and deregulated regulation of microvascular regression, or pruning, could contribute to the pathogenesis of neurodevelopmental diseases, stroke, and neurodegeneration. Aberrant remodeling of microvesselsis associated with blood-brain barrier breakdown, development of neuroinflammation, inadequate microcirculation in active brain regions, and leads to the dysfunction of the neurovascular unit and progressive neurological deficits. In this review, we summarize current data on the mechanisms of blood vessel regression and pruning in brain plasticity and in Alzheimer's-type neurodegeneration. We discuss some novel approaches to modulating cerebral remodeling and preventing degeneration-coupled aberrant microvascular activity in chronic neurodegeneration.

Discovery of novel phosphodiesterase-1 inhibitors for curing vascular dementia: suppression of neuroinflammation by blocking NF-κB transcription regulation and activating cAMP/CREB axis

Vascular dementia (VaD) is the second commonest type of dementia which lacks of efficient treatments currently. Neuroinflammation as a prominent pathological feature of VaD, is highly involved in the development of VaD. In order to verify the therapeutic potential of PDE1 inhibitors against VaD, the anti-neuroinflammation, memory and cognitive improvement were evaluated in vitro and in vivo by a potent and selective PDE1 inhibitor 4a. Also, the mechanism of 4a in ameliorating neuroinflammation and VaD was systematically explored. Furthermore, to optimize the drug-like properties of 4a, especially for metabolic stability, 15 derivatives were designed and synthesized. As a result, candidate 5f, with a potent IC₅₀ value of 4.5 nmol/L against PDE1C, high selectivity over PDEs, and remarkable metabolic stability, efficiently ameliorated neuron degeneration, cognition and memory impairment in VaD mice model by suppressing NF-κB transcription regulation and activating cAMP/CREB axis. These results further identified PDE1 inhibition could serve as a new therapeutic strategy for treatment of VaD.

Metabolic Syndrome and Vascular-Associated Cognitive Impairment: a Focus on Preclinical Investigations

PURPOSE OF REVIEW

Metabolic syndrome is associated with an increased risk of vascular cognitive impairment or, in the more extreme, vascular dementia. Animal models are used to investigate the relationship between pathology and behaviour. This review summarizes the latest understanding of the role of the hippocampus and prefrontal cortex in vascular cognitive impairment, the influence of inflammation in this association while also commenting on some of the latest interventions proposed.

RECENT FINDINGS

Models of vascular cognitive impairment and vascular dementia, whether they develop from an infarct or non-infarct base, demonstrate increased neuroinflammation, reduced neuronal function and deficits in prefrontal and hippocampal-associated cognitive domains. Promising new research shows agents and environmental interventions that inhibit central oxidative stress and inflammation can reverse both pathology and cognitive dysfunction. While preclinical studies suggest that reversal of deficits in vascular cognitive impairment models is possible, replication in patients still needs to be demonstrated.

P2X7R/NLRP3 signaling pathway-mediated pyroptosis and neuroinflammation contributed to cognitive impairment in a mouse model of migraine

Migraine is the second most common form of headache disorder and the second leading cause of disability worldwide. Cognitive symptoms ranked second resulting in migraine-related disability, after pain. P2X7 receptor (P2X7R) was recently shown to be involved in hyperalgesia in migraine. However, the role of P2X7R in migraine-related cognitive impairment is still ill-defined. The aim of this study was to explore the molecular mechanisms underlying migraine-related cognitive impairment and the role of P2X7R in it. Here we used a well-established mouse model of migraine that triggered migraine attacks by application of inflammatory soup (IS) to the dura. Our results showed that repeated dural IS stimulation triggered upregulation of P2X7R, activation of NLRP3 inflammasome, release of proinflammatory cytokines (IL-1β and IL-18) and activation of pyroptotic cell death pathway. Gliosis (microgliosis and astrogliosis), neuronal loss and cognitive impairment also occurred in the IS-induced migraine model. No significant apoptosis or whiter matter damage was observed following IS-induced migraine attacks. These pathological changes occurred mainly in the cerebral cortex and to a less extent in the hippocampus, all of which can be prevented by pretreatment with a specific P2X7R antagonist Brilliant Blue G (BBG). Moreover, BBG can alleviate cognitive impairment following dural IS stimulation. These results identified P2X7R as a key contributor to migraine-related cognitive impairment and may represent a potential therapeutic target for mitigating cognitive impairment in migraine. 

Effect of Yisui Multipurpose Soup's Amelioration on D-Galactose-Induced Neuronal Cells

This study clarified the regulatory effect of Yisui multipurpose Soup towards D-galactose-induced cognitive impairment cell model on the molecular level. We first constructed and cultured the cell model of cognitive impairment induced by D-galactose in neurons in vitro and then cultured the cells in the medium supplemented with different doses of drug-containing serum of Yisui multipurpose soup. Expressions of inflammatory cytokine tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), nitric oxide (NO), and interleukin-1β (IL-1β) were assessed by the ELISA and western blot, and cell apoptosis was determined by flow cytometry and TUNEL. The expression changes of apoptosis-related proteins Bcl-2 and Bax were estimated by immunofluorescence, qPCR, and western blot. Finally, we analyzed and made the network interaction diagram of Yisui multipurpose soup-components-targets through the network pharmacology method, from which we could learn that there were 1104 gene targets related to vascular cognitive impairment (VCI) and 1071 component targets of Yisui multipurpose soup. And there were 251 overlapping genes, mainly gathering in protein binding, protein modification, MAPK signaling pathway, and calcium signaling pathway. The expressions of TNF-α, iNOS, NO, and IL-1β were significantly decreased after the culture medium was replaced by medium containing drug serum. We also found that the effect of high-dose drug-containing serum on the expression of inflammatory factors was better than that of low dose. The Yisui multipurpose soup drug serum in the medium not only significantly increased Bcl-2 expression and effectively reduced Bax expression, but also inhibited the apoptosis of neurons induced by D-galactose. In conclusion, Yisui multipurpose soup could effectively protect D-galactose-induced neuronal cell cognitive impairment by orchestrating expressions of the inflammatory factors TNF-α, iNOS, NO, and IL-1β and the apoptosis-related proteins Bcl-2 and Bax.

Discovering the Effects of Fisetin on NF-κB/NLRP-3/NRF-2 Molecular Pathways in a Mouse Model of Vascular Dementia Induced by Repeated Bilateral Carotid Occlusion

Vascular dementia (VaD) is the second leading cause of dementia. The majority of VaD patients have cognitive abnormalities, which are caused by cerebral hypoperfusion-induced ischemia, endothelial dysfunction, oxidative stress, and neuroinflammation. Natural products are receiving increasing attention for the treatment of neuroinflammatory diseases. The aim of this study was to investigate the molecular pathways underlying the protective effects of fisetin, a flavonoid present in many fruits and vegetables, in a mouse model of VaD induced by repeated ischemia-reperfusion (IR) of the total bilateral carotid artery. Here, we found that VaD caused brain injury, lipid peroxidation, and neuronal death in the hippocampus, as well as astrocyte and microglial activation, and reduced BDNF neurotrophic factor expression together with behavioral alterations. In addition, VaD induced the activation of inflammasome components (NLRP-3, ASC, and caspase 1), and their downstream products (IL-1β and IL-18) release and promote activation of apoptotic cell death. Fisetin attenuated histological injury, malondialdehyde levels, inflammasome pathway activation, apoptosis, as well as increased BDNF expression, reduced astrocyte, microglial activation, and cognitive deficits. In conclusion, the protective effects of fisetin could be due to the inhibition of the ROS-induced activation of NF-κB/NLRP3 inflammasome together with the activation of antioxidant Nrf2/HO-1, suggesting a possible crosstalk between these molecular pathways.

Non-Communicable Neurological Disorders and Neuroinflammation

Traumatic brain injury, stroke, and neurodegenerative diseases represent a major cause of morbidity and mortality in Africa, as in the rest of the world. Traumatic brain and spinal cord injuries specifically represent a leading cause of disability in the younger population. Stroke and neurodegenerative disorders predominantly target the elderly and are a major concern in Africa, since their rate of increase among the ageing is the fastest in the world. Neuroimmunology is usually not associated with non-communicable neurological disorders, as the role of neuroinflammation is not often considered when evaluating their cause and pathogenesis. However, substantial evidence indicates that neuroinflammation is extremely relevant in determining the consequences of non-communicable neurological disorders, both for its protective abilities as well as for its destructive capacity. We review here current knowledge on the contribution of neuroinflammation and neuroimmunology to the pathogenesis of traumatic injuries, stroke and neurodegenerative diseases, with a particular focus on problems that are already a major issue in Africa, like traumatic brain injury, and on emerging disorders such as dementias.

Berberine protects against chronic cerebral hypoperfusion-induced cognitive impairment and hippocampal damage via regulation of the ERK/Nrf2 pathway

Vascular cognitive impairment caused by chronic cerebral hypoperfusion (CCH) seriously affects the quality of life of elderly patients and places a great burden on society and family. With the development of traditional Chinese medicine (TCM), TCM approaches to the prevention and treatment of senile ischemic cerebrovascular disease has received increasing attention. In this study, rats with bilateral common carotid artery occlusion (BCCAO) were treated with berberine (BBR). Their learning and memory function, neuronal injury and repair, the extracellular regulatory protein kinase (ERK)/nuclear factor-E2-related factor 2 (Nrf2) signaling pathway, and impairment and improvement of the blood-brain barrier (BBB) were evaluated. This study found that BBR can alleviate the pathological injury to the brain, reduce neuronal loss and promote neuronal cell survival after CCH by interfering with the ERK/Nrf2 signaling pathway. BBR can reduce BBB injury in CCH rats by inhibiting the expression of VEGF-A and MMP-9 in plasma, which reveals a protective effect of BBR on vascular cognitive impairment. This study provides a new research direction for BBR in the treatment of ischemic cerebrovascular disease.