Expression Of Neuroprotective Genes Research Articles

Protective effects of berberine against diabetes-associated cognitive decline in mice.

Diabetes associated cognitive decline (DACD) is a common CNS-related consequence of diabetes. The primary clinical manifestation of DACD includes learning and memory impairment. Unfortunately, there is no cure to delay the cognitive symptoms of diabetes. Although berberine (BBR) has shown promising effect in the treating diabetes and cognitive dysfunction, more research is needed to understand the mechanism of its therapeutic effect. For better understanding, we investigated the functions of BBR involved in anti-inflammation, anti-oxidant and neuroprotection in the hippocampus of diabetic mice. Diabetes was induced in mice using STZ. BBR was administered for 4 weeks before (pre-treatment), and after (post-treatment) STZ administration. The effect of BBR on cognitive functions in diabetic mice was determined using neurobehavioural test. Moreover, how BBR affected neuroinflammation, oxidative stress, and acetylcholine levels in the hippocampus and BBB permeability were analyzed using standard biochemical assays. Lastly, we evaluated the mRNA expression of neuroprotective genes in the hippocampus to uncover the mechanism of BBR. Treatment with BBR improved cognition in diabetic mice. It significantly reduced the levels of IL-6, iNOS, TNF-α, IL-1β, ROS and MDA and increased the levels of TAC, GSH, SOD and Catalase. Moreover, levels of acetylcholine and BBB permeability were reduced in the diabetic mice which was reversed by BBR treatment and increased the expression of IGF and BDNF in the hippocampus of diabetic mice. Our results suggest that BBR might be a potential therapeutic candidate for the treatment of DACD. Our study might serve as a basis for developing novel drugs for treating DACD.

Natto-derived dipeptide Gln-Gln attenuates scopolamine-induced memory impairment by enhancing cholinergic function in mice

This study investigated the efficacy of natto in counteracting memory impairment induced by scopolamine in mice and identified promising peptides. The peptide fraction prepared from natto fermented for 18 h with Bacillus subtilis var. natto TTCC12 improved memory retention and upregulated hippocampal neuroprotective gene expression, including for choline acetyltransferase (ChAT) and brain-derived neurotrophic factor. Metabolomic analysis revealed that several dipeptides, such as Gln-Leu, Gln-Ile, Gln-Gln, and Ala-Tyr, increased in the blood 60 min after oral administration of the natto peptide fraction in rats. These dipeptides significantly attenuated scopolamine-induced memory impairment and increased brain acetylcholine (ACh) levels. Specifically, Gln-Gln exhibited a dose-dependent improvement by enhancing cholinergic function through increased levels of ACh and ChAT. However, an equimolar amount of Gln, as a free amino acid, showed no significant effects. Therefore, this study demonstrated the potential of natto and its constituents, particularly dipeptides Gln-Gln, in mitigating cognitive impairment.

Plant extracts and omega-3 supplementation modulate hippocampal oxylipin profile in response to LPS-induced neuroinflammation

Objective and designNeuroinflammation is a protective mechanism but can become harmful if chronic and/or unregulated, leading to neuronal damage and cognitive alterations. Limiting inflammation and promoting resolution could be achieved with nutrients such as grapes and blueberries polyphenols, saffron carotenoids, and omega-3, which have anti-inflammatory and proresolutive properties.MethodsThis study explored the impact of 18-day supplementation with plant extracts (grape, blueberry and saffron), omega-3 or both (mix) on neuroinflammation induced by lipopolysaccharide (LPS, 250 µg/kg) in 149 mice at different time points post-LPS treatment (30 min, 2 h, 6 h). Inflammatory, oxidative and neuroprotective gene expression; oxylipin quantification; and fatty acid composition were analyzed at each time point. PCA analysis was performed with all these biomarkers.ResultsMix supplementation induced changes in the resolution of inflammation. In fact, the production of proinflammatory mediators in the hippocampus started earlier in the supplemented group than in the LPS group. Pro-resolving mediators were also found in higher quantities in supplemented mice. These changes were associated with increased hippocampal antioxidant status at 6 h post-LPS.ConclusionsThese findings suggest that such dietary interventions with plant extracts, and omega-3 could be beneficial in preventing neuroinflammation and, consequently, age-related cognitive decline. Further research is needed to explore the effects of these supplements on chronic inflammation in the context of aging.

Prospects for the Use of Thymoquinone (a Component of Nigella sativa) in the Prevention and Therapy of Neuropathologies

Black cumin and its component thymoquinone (TQ) are known as drugs with a wide range of pharmacological activities: immunomodulating, anti-inflammatory, antimicrobial, antiviral, antineoplastic properties. These drugs also have neuroprotective properties in neurodegenerative diseases (Alzheimer's, Parkinson's), ischaemia, epilepsy, encephalomyelitis, traumatic brain injury. The main mechanisms of action are antioxidant activity increased expression of neuroprotective genes and proteins with decreased activity of pro-inflammatory cytokines and the NF-кB pathway, which plays a key role in neuroinflammation. A separate section is devoted to the effects of black cumin and TQ on the course of depression, a common and socially significant illness. Reduced signs of depression and increased levels of a neuroprotective factor belonging to the neutrophin family (BDNF), a characteristic marker of depression, were described in 54 depressed patients. The review discusses the prospects for prevention and therapy with these drugs in central nervous system pathology.

Reversal of injury-associated retinal ganglion cell gene expression by a phosphodiesterase anchoring disruptor peptide

Loss of retinal ganglion cells (RGCs) is central to the pathogenesis of optic neuropathies such as glaucoma. Increased RGC cAMP signaling is neuroprotective. We have shown that displacement of the cAMP-specific phosphodiesterase PDE4D3 from an RGC perinuclear compartment by expression of the modified PDE4D3 N-terminal peptide 4D3(E) increases perinuclear cAMP and protein kinase A activity in cultured neurons and in vivo RGC survival after optic nerve crush (ONC) injury. To explore mechanisms by which PDE4D3 displacement promotes neuroprotection, in this study mice intravitreally injected with an adeno-associated virus to express an mCherry-tagged 4D3(E) peptide were subjected to ONC injury and analyzed by single cell RNA-sequencing (scRNA-seq). 4D3(E)-mCherry expression was associated with an attenuation of injury-induced changes in gene expression, thereby supporting the hypothesis that enhanced perinuclear PKA signaling promotes neuroprotective RGC gene expression.

Up-regulation of miR-126 via DNA methylation in hypoxia-preconditioned endothelial cells may contribute to hypoxic tolerance of neuronal cells.

Endothelial cells (ECs) can confer neuroprotection by secreting molecules. This study aimed to investigate whether DNA methylation contributes to the neuroprotective gene expression induced by hypoxia preconditioning (HPC) in ECs and to clarify that the secretion of molecules from HPC ECs may be one of the molecular mechanisms of neuroprotection. Human microvascular endothelial cell-1 (HMEC-1) was cultured under normal conditions (C), hypoxia(H), and hypoxia preconditioning (HPC), followed by the isolation of culture medium (CM). SY5Y cell incubated with the isolated CM from HMEC-1 was exposed to oxygen-glucose deprivation (OGD). The DNA methyltransferases (DNMTs), global methylation level, miR-126 and its promotor DNA methylation level in HMEC-1 were measured. The cell viability and cell injury in SY5Y were detected. HPC decreased DNMTs level and global methylation level as well as increased miR-126 expression in HMEC-1. CM from HPC treated HMEC-1 also relieved SY5Y cell damage, while CM from HMEC-1 which over-expression of miR-126 can reduce injury in SY5Y under OGD condition. These findings indicate EC may secrete molecules, such as miR-126, to execute neuroprotection induced by HPC through regulating the expression of DNMTs.

Brain-targeted delivery of neuroprotective survival gene minimizing hematopoietic cell contamination: implications for Parkinson’s disease treatment

BackgroundNeurodegenerative diseases, including Parkinson's disease, Amyotropic Lateral Sclerosis (ALS) and Alzheimer's disease, present significant challenges for therapeutic development due to drug delivery restrictions and toxicity concerns. Prevailing strategies often employ adeno-associated viral (AAV) vectors to deliver neuroprotective survival genes directly into the central nervous system (CNS). However, these methods have been limited by triggering immunogenic responses and risk of tumorigenicity, resulting from overexpression of survival genes in peripheral blood mononuclear cells (PBMC), thereby increasing the risk of tumorigenicity in specific immune cells. Thus, by coding selectively suppressive microRNA (miRNA) target sequences in AAV genome, we designed CNS-targeted neuroprotective gene expression vector system without leakage to blood cells.MethodsTo minimize the potential for transgene contamination in the blood, we designed a CNS-specific AAV system. Our system utilized a self-complementary AAV (scAAV), encoding a quadruple repeated target sequence of the hematopoietic cell-specific miR142-3p at the 3' untranslated region (UTR). As a representative therapeutic survival gene for Parkinson’s disease treatment, we integrated DX2, an antagonistic splice variant of the apoptotic gene AIMP2, known to be implicated in Parkinson's disease, into the vector.ResultsThis configuration ensured that transgene expression was stringently localized to the CNS, even if the vector found its way into the blood cells. A single injection of scAAV-DX2 demonstrated marked improvement in behavior and motor activity in animal models of Parkinson’s disease induced by either Rotenone or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Importantly, comprehensive preclinical data adhering to Good Laboratory Practice (GLP) standards revealed no adverse effects in the treated animals.ConclusionsOur CNS-specific vector system, which encodes a survival transgene DX2, signifies a promising avenue for safe gene therapy, avoiding unintended expression of survival gene in blood cells, applicable to various neurodegenerative diseases.

Single-Cell Multiome Analysis Reveals Neuroprotection by Elovanoids in Experimental Ischemic Stroke

Ischemic stroke results in severe loss of neurological functions, and a large proportion of survivors display the onset of cognitive impairments. Administration of a novel class of very long-chain polyunsaturated fatty acids (VLC-PUFAs) termed elovanoids (ELV-N34) or its VLC-PUFA precursor (C34:6) are protective against both in vitro and in vivo models of uncompensated oxidative stress and ischemic stress. We found that ELV-N34 or C34:6 delivery attenuates sensorimotor deficits after ischemic stroke. Furthermore, we uncovered that ELV and its precursors protect against ischemic damage by modulating inflammatory signaling and increasing the expression of neuroprotective genes. We used 10X Single Cell Multiome (ATAC + Gene Expression) to compare genomic and epigenomic responses in naïve rats and after experimental ischemic treatment. Adult Sprague-Dawley rats underwent 2 hours of middle cerebral artery occlusion (MCAo) via intraluminal suture. Rats received vehicle, ELV-N34, or C34:6 delivered intranasally 1 hour, 1 day, and 2 days after 2 hours of MCAo. Brains were harvested on day 3 from the ipsilesional cortex (penumbra region) and subcortex. Nuclei were isolated and processed according to 10X Genomics Single Cell Multiome protocol. ELV-N34 or C34:6 treatment reduced neurological deficits after MCAo. Joint single-cell analysis revealed increases in microglia and leukocyte abundance as well as a loss of neuronal populations after MCAo. Differential gene expression revealed that ELV or its precursors protected against MCAo through complex mechanisms involving anti- inflammatory signaling and promoted neuroregeneration in microglia, astrocytes, neurons, and other neural cells. ELV/precursors exert their bioactivity by modulating conversion to neuroprotective cell phenotypes in neurodegenerative diseases such as stroke or Alzheimer's disease.

Amyloid β-Oligomers Inhibit the Nuclear Ca2+ Signals and the Neuroprotective Gene Expression Induced by Gabazine in Hippocampal Neurons.

Hippocampal neuronal activity generates dendritic and somatic Ca2+ signals, which, depending on stimulus intensity, rapidly propagate to the nucleus and induce the expression of transcription factors and genes with crucial roles in cognitive functions. Soluble amyloid-beta oligomers (AβOs), the main synaptotoxins engaged in the pathogenesis of Alzheimer's disease, generate aberrant Ca2+ signals in primary hippocampal neurons, increase their oxidative tone and disrupt structural plasticity. Here, we explored the effects of sub-lethal AβOs concentrations on activity-generated nuclear Ca2+ signals and on the Ca2+-dependent expression of neuroprotective genes. To induce neuronal activity, neuron-enriched primary hippocampal cultures were treated with the GABAA receptor blocker gabazine (GBZ), and nuclear Ca2+ signals were measured in AβOs-treated or control neurons transfected with a genetically encoded nuclear Ca2+ sensor. Incubation (6 h) with AβOs significantly reduced the nuclear Ca2+ signals and the enhanced phosphorylation of cyclic AMP response element-binding protein (CREB) induced by GBZ. Likewise, incubation (6 h) with AβOs significantly reduced the GBZ-induced increases in the mRNA levels of neuronal Per-Arnt-Sim domain protein 4 (Npas4), brain-derived neurotrophic factor (BDNF), ryanodine receptor type-2 (RyR2), and the antioxidant enzyme NADPH-quinone oxidoreductase (Nqo1). Based on these findings we propose that AβOs, by inhibiting the generation of activity-induced nuclear Ca2+ signals, disrupt key neuroprotective gene expression pathways required for hippocampal-dependent learning and memory processes.

Stimulation of Angiotensin II Type 2 Receptor Modulates Pro-Inflammatory Response in Microglia and Macrophages: Therapeutic Implications for the Treatment of Stroke.

Sustained microglial activation contributes to the development of post-stroke cognitive impairment (PSCI). Compound 21 (C21), an angiotensin II type 2 receptor agonist, has shown some neurovascular protection after stroke. This study aimed to investigate the direct anti-inflammatory effects of C21 on macrophages, as well as brain innate immune cells. Murine microglial cell line (C8-B4) and RAW 264.7 macrophages were exposed to lipopolysaccharide (LPS) and co-treated with C21. Pro-inflammatory mediators were assessed via RT-qPCR and ELISA. Cellular reactive oxygen species (ROS) were evaluated via CellROXGreen staining, and nitrate production was assessed using Griess assay. C21 suppressed LPS-induced inflammation and ROS generation in both cells. In microglia, C21 blunted LPS-induced mRNA expression of IL-1β, IL-12b, COX-1, iNOS, and IL-6. A similar pattern was observed in macrophages, where C21 suppressed LPS-induced IL-1β, TNF-α, and CXCL1 expression. These anti-inflammatory effects in microglia and macrophages were associated with increased neuroprotective gene expression, including GDNF and BDNF, in a dose-dependent manner. Our findings suggest a protective effect of C21 against the inflammatory response, in both macrophages and microglia, via suppression of the release of pro-inflammatory cytokines/chemokines and the generation of ROS while stimulating the production of neurotrophic factors.

Beneficial Effects of Probiotic Bifidobacterium longum in a Lithium-Pilocarpine Model of Temporal Lobe Epilepsy in Rats.

Epilepsy is a challenging brain disorder that is often difficult to treat with conventional therapies. The gut microbiota has been shown to play an important role in the development of neuropsychiatric disorders, including epilepsy. In this study, the effects of Bifidobacterium longum, a probiotic, on inflammation, neuronal degeneration, and behavior are evaluated in a lithium-pilocarpine model of temporal lobe epilepsy (TLE) induced in young adult rats. B. longum was administered orally at a dose of 109 CFU/rat for 30 days after pilocarpine injection. The results show that B. longum treatment has beneficial effects on the TLE-induced changes in anxiety levels, neuronal death in the amygdala, and body weight recovery. In addition, B. longum increased the expression of anti-inflammatory and neuroprotective genes, such as Il1rn and Pparg. However, the probiotic had little effect on TLE-induced astrogliosis and microgliosis and did not reduce neuronal death in the hippocampus and temporal cortex. The study suggests that B. longum may have a beneficial effect on TLE and may provide valuable insights into the role of gut bacteria in epileptogenesis. In addition, the results show that B. longum may be a promising drug for the comprehensive treatment of epilepsy.

Beyond the Mat: Exploring the Potential Clinical Benefits of Yoga on Epigenetics and Gene Expression: A Narrative Review of the Current Scientific Evidence.

Yoga, an ancient practice rooted in Indian philosophy, has gained widespread popularity for its numerous physical and mental health benefits. In the recent years, there has been growing interest in understanding how yoga influences gene expression and epigenetic modifications. This narrative review investigates the molecular mechanisms, by which yoga influences gene expression, focusing on deoxyribonucleic acid (DNA) methylation, and histone modifications. Research literature was sourced from various databases to select randomized clinical trials and comparative cohort studies examining yoga's impact on gene expression and epigenetic changes. Our findings suggest that yoga could exert anti-inflammatory effects, as it downregulates pro-inflammatory cytokines, soluble interleukin IL-2 receptor gene expression, and transcription factors. Yoga also boosts the innate antiviral response and brain health by enhancing natural defense genes and microRNA-29c expression. Notably, it activates telomerase, linked with cellular longevity, and promotes nitric oxide synthetase and neuroprotective gene expression, implying benefits for ocular health. In addition, yoga fosters DNA repair and cellular integrity maintenance by increasing oxoguanine glycosylase one protein and p53 gene expression. However, the diversity of yoga interventions in these studies complicates direct comparisons and broader application. The current research primarily focuses on short-term outcomes, offering a limited understanding of yoga's long-term epigenetic impacts. Future research should address these gaps by studying the enduring effects of Yoga, personalizing interventions, and contrasting techniques.

OPA1 Dominant Optic Atrophy: Pathogenesis and Therapeutic Targets.

OPA1 Dominant Optic Atrophy: Pathogenesis and Therapeutic Targets.

Substance P Reduces Infarct Size and Mortality After Ischemic Stroke, Possibly Through the M2 Polarization of Microglia/Macrophages and Neuroprotection in the Ischemic Rat Brain.

Substance-P (SP) is an 11 amino acid neuropeptide that is known to stimulate the peripheral mobilization of bone marrow mesenchymal stem cells and M2 polarization in monocytes/macrophages in a variety of acute and chronic tissue injuries. To examine the role of SP in protection and recovery from acute ischemic brain injury, experimental ischemic stroke was induced by transient middle cerebral artery occlusion (tMCAo) in rats for 1h with subsequent reperfusion. Two injections of SP, immediately and one day post-tMCAo, resulted in approximately threefold lower mortality and 40% less infarct volume than those of saline-treated rats at seven days post-tMCAo. At 4.5h, SP markedly increased CD11b/c+CD163+/CD 206+ cells in the blood, which were concomitantly decreased in the bone marrow, suggesting that SP preferentially mobilized M2-polarized monocytes. After two days, SP increased the expression of neuroprotective and anti-inflammatory genes in the ischemic brain and induced neuronal survival in the brain penumbra. Additionally, SP markedly increased CD68+CD163+ and CD68+CD206+ M2 microglia/macrophages in the ischemic brain during seven days post-tMCAo. Furthermore, SP preserved the blood‒brain barrier in the ischemic brain, which was confirmed by the abundant levels of SMI71+ brain endothelial cells that colocalized with α-SMA+ pericytes. The beneficial effects of SP on functional recovery and tissue preservation were maintained for six weeks. Collectively, SP treatment in the early phase of ischemic stroke markedly suppressed the destructive inflammatory response and improved the microenvironment for tissue protection and repair.

Effects of Long-Term Administration of Q808 on Hippocampal Transcriptome in Healthy Rats.

Epilepsy treatment with antiepileptic drugs (AEDs) is usually requires for many years. Q808 is an innovative antiepileptic chemical. It exerts effective antiepileptic effect against various epilepsy models. Exploring the gene transcriptomic profile of long-term treatment of Q808 is necessary. In the present study, hippocampus RNA-sequencing was performed to reveal the transcriptome profile of rats before and after treatment of Q808 for 28 d. Results confirmed 51 differentially expressed genes (DEGs) between Q808 and healthy control groups. Gene cluster analysis showed that most upregulated DEGs linked to response to drug and nucleus, most downregulated DEGs linked to locomotory, neuronal cell body, and drug binding. Most of DEGs were enriched in the signaling transduction, substance dependence, nervous system, and neurodegenerative disease pathways. Furthermore, quantitative real-time PCR analysis confirmed that Q808 significantly increased the expression of neuroprotective genes, such as Mdk, and decreased the mRNA levels of Penk, Drd1, and Adora2a, which are highly expressed in epilepsy models. In addition, Q808 decreased the mRNA expression of Pde10A and Drd2, which are known to be closely associated with schizophrenia. Our study may provide a theoretical basis to explore the effect of Q808 on the susceptibility to epilepsy and other neurological diseases.

JOTROL, a Novel Formulation of Resveratrol, Shows Beneficial Effects in the 3xTg-AD Mouse Model.

Alzheimer's disease (AD) has minimally effective treatments currently. High concentrations of resveratrol, a polyphenol antioxidant found in plants, have been reported to affect several AD-related and neuroprotective genes. To address the low bioavailability of resveratrol, we investigated a novel oral formulation of resveratrol, JOTROL™, that has shown increased pharmacokinetic properties compared to non-formulated resveratrol in animals and in humans. We hypothesized that equivalent doses of JOTROL, compared to non-formulated resveratrol, would result in greater brain exposure to resveratrol, and more efficacious responses on AD biomarkers. For sub-chronic reversal studies, 15-month-old male triple transgenic (APPSW/PS1M146V/TauP301L; 3xTg-AD) AD mice were treated orally with vehicle or 50 mg/kg JOTROL for 36 days. For prophylactic studies, male and female 3xTg-AD mice were similarly administered vehicle, 50 mg/kg JOTROL, or 50 mg/kg resveratrol for 9 months starting at 4 months of age. A behavioral battery was run, and mRNA and protein from brain and blood were analyzed for changes in AD-related gene and protein expression. JOTROL displays significantly increased bioavailability over non-formulated resveratrol. Treatment with JOTROL resulted in AD-related gene expression changes (Adam10, Bace1, Bdnf, Psen1) some of which were brain region-dependent and sex-specific, as well as changes in inflammatory gene and cytokine levels. JOTROL may be effective as a prophylaxis and/or treatment for AD through increased expression and/or activation of neuroprotective genes, suppression of pro-inflammatory genes, and regulation of central and peripheral cytokine levels.

Using a Transection Paradigm to Enhance the Repair Mechanisms of an Investigational Human Cell Therapy

One promising strategy in cell therapies for Parkinson’s disease (PD) is to harness a patient’s own cells to provide neuroprotection in areas of the brain affected by neurodegeneration. No treatment exists to replace cells in the brain. Thus, our goal has been to support sick neurons and slow neurodegeneration by transplanting living repair tissue from the peripheral nervous system into the substantia nigra of those with PD. Our group has pioneered the transplantation of transection-activated sural nerve fascicles into the brain of human subjects with PD. Our experience in sural nerve transplantation has supported the safety and feasibility of this approach. As part of a paradigm to assess the reparative properties of human sural nerve following a transection injury, we collected nerve tissue approximately 2 weeks after sural nerve transection for immunoassays from 15 participants, and collected samples from two additional participants for single nuclei RNA sequencing. We quantified the expression of key neuroprotective and select anti-apoptotic genes along with their corresponding protein levels using immunoassays. The single nuclei data clustered into 10 distinctive groups defined on the basis of previously published cell type-specific genes. Transection-induced reparative peripheral nerve tissue showed RNA expression of neuroprotective factors and anti-apoptotic factors across multiple cell types after nerve injury induction. Key proteins of interest (BDNF, GDNF, beta-NGF, PDGFB, and VEGF) were upregulated in reparative tissue. These results provide insight on this repair tissue’s utility as a neuroprotective cell therapy.

Oral Administration of Lipopolysaccharide Prevents Cognitive Impairment in Streptozotocin-induced Diabetic Mice in a Blood Glucose-independent Manner.

Diabetes is a risk factor for dementia. However, no radical preventive method for diabetes-associated dementia has yet been developed. Our previous study revealed that oral administration of lipopolysaccharide (LPS) prevents high-fat diet-induced cognitive impairment. Therefore, we investigated here whether oral administration of LPS (OAL) could also prevent diabetes-associated dementia. Diabetic mice were produced by intraperitoneal administration of streptozotocin (STZ), and then mice were orally administered LPS. Cognitive ability was evaluated using the Morris water maze, and gene expression was analyzed in isolated microglia. OAL prevented STZ-induced diabetic cognitive impairment, but did not affect blood glucose levels. Moreover, OAL promoted the expression of neuroprotective genes in microglia, such as heat shock protein family 40 (HSP40) and chemokine CCL7. OAL prevents diabetes-associated dementia, potentially via promotion of HSP40 and CCL7 expression in microglia.

Vitamin D as a modifiable risk factor, predictor, and theoretical therapeutic agent for vasospasm in spontaneous subarachnoid hemorrhage.

Delayed deterioration associated with cerebral vasospasm (CVS) is a feared complication after spontaneous subarachnoid hemorrhage (SAH) and is one of the leading causes of death in patients with intracranial hemorrhage. The pathophysiology of vasospasm is complex and not fully understood, involving multiple inflammatory pathways in addition to vasoconstriction induced ischemia. Current treatment with anti-inflammatory or vasodilatory medications has been met with limited success and has not led to a decrease in vasospastic associated mortality prompting continued investigation of potential treatment options. The active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25-VitD3), is a hormone with downstream effects that induce anti-inflammatory pathways, promote nitric oxide (NO) induced vasodilation, and lead to neuroprotective-gene expression, which may be useful in mitigating the vascular pathogenesis associated with CVS. A high prevalence of vitamin D deficiency has been identified in patients admitted with SAH. Low vitamin D levels in patients, as determined by time of year, has also been correlated to an increased incidence and severity of CVS. Further, the therapeutic usefulness of 1,25-VitD3 has been demonstrated in animal models leading to a decreased incidence of CVS but has yet to be thoroughly investigated in human studies. In this review, we will discuss the findings that suggest the potential of utilizing vitamin D as a predictive indicator, method of prevention, and or treatment option for CVS in patients following spontaneous SAH.

Inhibition of Epigenetic Modifiers LSD1 and HDAC1 Blocks Rod Photoreceptor Death in Mouse Models of Retinitis Pigmentosa

Epigenetic modifiers are increasingly being investigated as potential therapeutics to modify and overcome disease phenotypes. Diseases of the nervous system present a particular problem as neurons are postmitotic and demonstrate relatively stable gene expression patterns and chromatin organization. We have explored the ability of epigenetic modifiers to prevent degeneration of rod photoreceptors in a mouse model of retinitis pigmentosa (RP), using rd10 mice of both sexes. The histone modification eraser enzymes lysine demethylase 1 (LSD1) and histone deacetylase 1 (HDAC1) are known to have dramatic effects on the development of rod photoreceptors. In the RP mouse model, inhibitors of these enzymes blocked rod degeneration, preserved vision, and affected the expression of multiple genes including maintenance of rod-specific transcripts and downregulation of those involved in inflammation, gliosis, and cell death. The neuroprotective activity of LSD1 inhibitors includes two pathways. First, through targeting histone modifications, they increase accessibility of chromatin and upregulate neuroprotective genes, such as from the Wnt pathway. We propose that this process is going in rod photoreceptors. Second, through nonhistone targets, they inhibit transcription of inflammatory genes and inflammation. This process is going in microglia, and lack of inflammation keeps rod photoreceptors alive.SIGNIFICANCE STATEMENT Retinal degenerations are a leading cause of vision loss. RP is genetically very heterogeneous, and the multiple pathways leading to cell death are one reason for the slow progress in identifying suitable treatments for patients. Here we demonstrate that inhibition of LSD1and HDAC1 in a mouse model of RP leads to preservation of rod photoreceptors and visual function, retaining of expression of rod-specific genes, and with decreased inflammation, cell death, and Müller cell gliosis. We propose that these epigenetic inhibitors cause more open and accessible chromatin, allowing expression of neuroprotective genes. A second mechanism that allows rod photoreceptor survival is suppression of inflammation by epigenetic inhibitors in microglia. Manipulation of epigenetic modifiers is a new strategy to fight neurodegeneration in RP.