Enhanced Therapeutic Potential of Nano-Curcumin Against Subarachnoid Hemorrhage-Induced Blood–Brain Barrier Disruption Through Inhibition of Inflammatory Response and Oxidative Stress

Platelet Membrane-Coated Curcumin-PLGA Nanoparticles Promote Astrocyte-Neuron Transdifferentiation for Intracerebral Hemorrhage Treatment

Intracerebral hemorrhage (ICH) is a hemorrhagic disease with high mortality and disability rates. Curcumin is a promising drug for ICH treatment due to its multiple biological activities, but its application is limited by its poor watersolubility and instability. Herein, platelet membrane-coated curcumin polylactic-co-glycolic acid (PLGA) nanoparticles (PCNPs) are prepared to achieve significantly improved solubility, stability, and sustained release of curcumin. Fourier transform infrared spectra and X-ray diffraction assays indicate good encapsulation of curcumin within nanoparticles. Moreover, it is revealed for the first time that curcumin-loaded nanoparticles can not only suppress hemin-induced astrocyte proliferation but also induce astrocytes into neuron-like cells in vitro. PCNPs are used to treat rat ICH by tail vein injection, using in situ administration as control. The results show that PCNPs are more effective than curcumin-PLGA nanoparticles in concentrating on hemorrhagic lesions, inhibiting inflammation, suppressing astrogliosis, promoting neurogenesis, and improving motor functions. The treatment efficacy of intravenously administered PCNPs is comparable to that of in situ administration, indicating a good targeting effect of PCNPs on the hemorrhage site. This study provides a potent treatment for hemorrhagic injuries and a promising solution for efficient delivery of water-insoluble drugs using composite materials of macromolecules and cell membranes.

Low-dose IL-2 treatment confers anti-inflammatory effect against subarachnoid hemorrhage in mice

Objective

Subarachnoid hemorrhage (SAH) was a stroke with high occurrence and mortality. At the early stage, SAH patients have severe cerebral injury which is contributed by inflammation. In this study, we aimed to explore the anti-inflammation effect of low-dose IL-2 in SAH mice.

Methods

The 12-week-old C57BL/6J male mice were conducted with SAH surgery (Internal carotid artery puncture method). Different dose of IL-2 was injected intraperitoneally for 1 h, 1 day, and 2 days after SAH. Single-cell suspension and flow cytometry were used for the test of regulatory T (Treg) cells. Immunofluorescence staining was used to investigate the phenotypic polarization of microglia and inflammation response around neurons. Enzyme-Linked Immuno-sorbent Assay (ELISA) was applied to detect the level of pro-inflammatory factors.

Results

Low-dose IL-2 could enrich the Treg cells and drive the microglia polarizing to M2. The level of pro-inflammatory factors, IL-1α, IL-6, and TNF-α decreased in the low-dose IL-2 group. The inflammation response around neurons was attenuated. Low-dose IL-2 could increase the number of Treg cells, which could exert a neuroprotective effect against inflammation after SAH.

Conclusion

Low-dose IL-2 had the potential to be an effective clinical method to inhibit inflammation after SAH.

The development of nanocarriers for natural products

Natural bioactive compounds from plants exhibit substantial pharmacological potency and therapeutic value. However, the development of most plant bioactive compounds is hindered by low solubility and instability. Conventional pharmaceutical forms, such as tablets and capsules, only partially overcome these limitations, restricting their efficacy. With the recent development of nanotechnology, nanocarriers can enhance the bioavailability, stability, and precise intracellular transport of plant bioactive compounds. Researchers are increasingly integrating nanocarrier-based drug delivery systems (NDDS) into the development of natural plant compounds with significant success. Moreover, natural products benefit from nanotechnological enhancement and contribute to the innovation and optimization of nanocarriers via self-assembly, grafting modifications, and biomimetic designs. This review aims to elucidate the collaborative and reciprocal advancement achieved by integrating nanocarriers with botanical products, such as bioactive compounds, polysaccharides, proteins, and extracellular vesicles. This review underscores the salient challenges in nanomedicine, encompassing long-term safety evaluations of nanomedicine formulations, precise targeting mechanisms, biodistribution complexities, and hurdles in clinical translation. Further, this study provides new perspectives to leverage nanotechnology in promoting the development and optimization of natural plant products for nanomedical applications and guiding the progression of NDDS toward enhanced efficiency, precision, and safety. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Exploiting Natural Niches with Neuroprotective Properties: A Comprehensive Review

Natural products from mushrooms, plants, microalgae, and cyanobacteria have been intensively explored and studied for their preventive or therapeutic potential. Among age-related pathologies, neurodegenerative diseases (such as Alzheimer's and Parkinson's diseases) represent a worldwide health and social problem. Since several pathological mechanisms are associated with neurodegeneration, promising strategies against neurodegenerative diseases are aimed to target multiple processes. These approaches usually avoid premature cell death and the loss of function of damaged neurons. This review focuses attention on the preventive and therapeutic potential of several compounds derived from natural sources, which could be exploited for their neuroprotective effect. Curcumin, resveratrol, ergothioneine, and phycocyanin are presented as examples of successful approaches, with a special focus on possible strategies to improve their delivery to the brain.

Reactive oxygen species (ROS) scavenging biomaterials for anti-inflammatory diseases: from mechanism to therapy

Inflammation is a fundamental defensive response to harmful stimuli, but the overactivation of inflammatory responses is associated with most human diseases. Reactive oxygen species (ROS) are a class of chemicals that are generated after the incomplete reduction of molecular oxygen. At moderate levels, ROS function as critical signaling molecules in the modulation of various physiological functions, including inflammatory responses. However, at excessive levels, ROS exert toxic effects and directly oxidize biological macromolecules, such as proteins, nucleic acids and lipids, further exacerbating the development of inflammatory responses and causing various inflammatory diseases. Therefore, designing and manufacturing biomaterials that scavenge ROS has emerged an important approach for restoring ROS homeostasis, limiting inflammatory responses and protecting the host against damage. This review systematically outlines the dynamic balance of ROS production and clearance under physiological conditions. We focus on the mechanisms by which ROS regulate cell signaling proteins and how these cell signaling proteins further affect inflammation. Furthermore, we discuss the use of potential and currently available-biomaterials that scavenge ROS, including agents that were engineered to reduce ROS levels by blocking ROS generation, directly chemically reacting with ROS, or catalytically accelerating ROS clearance, in the treatment of inflammatory diseases. Finally, we evaluate the challenges and prospects for the controlled production and material design of ROS scavenging biomaterials.

Nanocarrier-mediated curcumin delivery: An adjuvant strategy for CNS disease treatment

Neurological disorders are a major global challenge, which counts for a substantial slice of disease burden around the globe. In these, the challenging landscape of central nervous system (CNS) diseases, including Alzheimer's disease, Parkinson's disease, multiple sclerosis, and neuro-AIDS, demands innovative and novel therapeutic approaches. Curcumin, a versatile natural compound with antioxidant and anti-inflammatory properties, shows great potential as a CNS adjuvant therapy. However, its limited bioavailability and suboptimal permeability to the blood-brain barrier (BBB) hamper the therapeutic efficacy of curcumin. This review explores how nanocarrier facilitates curcumin delivery, which has shown therapeutic efficacy for various non-CNS diseases, for example, cancers, and can also revolutionize the treatment outcomes in patients with CNS diseases. Toward this, intranasal administration of curcumin as a non-invasive CNS drug delivery route can also aid its therapeutic outcomes as an adjuvant therapy for CNS diseases. Intranasal delivery of nanocarriers with curcumin improves the bioavailability of curcumin and its BBB permeability, which is instrumental in promoting its therapeutic potential. Furthermore, curcumin's inhibitory effect on efflux transporters will help to enhance the BBB and cellular permeability of various CNS drugs. The therapeutic potential of curcumin as an adjuvant has the potential to yield synergistic effects with CNS drugs and will help to reduce CNS drug doses and improve their safety profile. Taken together, this approach holds a promise for reshaping CNS disease management by maximizing curcumin's and other drugs' therapeutic benefits.

Use of Poly Lactic-co-glycolic Acid Nano and Micro Particles in the Delivery of Drugs Modulating Different Phases of Inflammation

Chronic inflammation contributes to the pathogenesis of many diseases, including apparently unrelated conditions such as metabolic disorders, cardiovascular diseases, neurodegenerative diseases, osteoporosis, and tumors, but the use of conventional anti-inflammatory drugs to treat these diseases is generally not very effective given their adverse effects. In addition, some alternative anti-inflammatory medications, such as many natural compounds, have scarce solubility and stability, which are associated with low bioavailability. Therefore, encapsulation within nanoparticles (NPs) may represent an effective strategy to enhance the pharmacological properties of these bioactive molecules, and poly lactic-co-glycolic acid (PLGA) NPs have been widely used because of their high biocompatibility and biodegradability and possibility to finely tune erosion time, hydrophilic/hydrophobic nature, and mechanical properties by acting on the polymer's composition and preparation technique. Many studies have been focused on the use of PLGA-NPs to deliver immunosuppressive treatments for autoimmune and allergic diseases or to elicit protective immune responses, such as in vaccination and cancer immunotherapy. By contrast, this review is focused on the use of PLGA NPs in preclinical in vivo models of other diseases in which a key role is played by chronic inflammation or unbalance between the protective and reparative phases of inflammation, with a particular focus on intestinal bowel disease; cardiovascular, neurodegenerative, osteoarticular, and ocular diseases; and wound healing.

Effects of curcumin nanodelivery on schizophrenia and glioblastoma

Curcumin is a natural polyphenol, which has a variety of pharmacological activities, including, antineoplastic, antioxidative and neuroprotective effects. Recent studies provided evidence for the bioactive role of curcumin in the prevention and treatment of various central nervous system (CNS)-related diseases including Parkinson's, Alzheimer's, Schizophrenia disease and glioma neoplasia. Schizophrenia is a disabling psychiatric disorder related with an aberrant functional coupling between hippocampus and prefrontal cortex that might be crucial for cognitive dysfunction. Animal studies have lent support to the hypothesis that curcumin could improve cognitive functioning and enhance cell proliferation of dentate gyrus. In relation to brain tumors, specifically gliomas, the antineoplastic action of curcumin is based on the inhibition of cell growth promoting apoptosis or autophagy and preventing angiogenesis. However, one of the main impediments for the application of curcumin to patients is its low bioavailability. In intracranial lesions, curcumin has problems to cross the blood-brain barrier (BBB). Currently nano-based drug delivery systems are opening a new horizon to tackle this problem. The bioavailability and effective release of curcumin can be made possible in the form of nanocurcumin. This nanoformulation preserves the properties of curcumin and makes it reach tissues with pathology. This review try to study the beneficial effects of the curcumin nanodelivery in central nervous pathologies such us schizophrenia and glioma disease.

Curcumin and chemokines: mechanism of action and therapeutic potential in inflammatory diseases

Chemokines belong to the family of cytokines with chemoattractant properties that regulate chemotaxis and leukocyte migration, as well as the induction of angiogenesis and maintenance of hemostasis. Curcumin, the major component of the Curcuma longa rhizome, has various pharmacological actions, including anti-inflammatory, immune-regulatory, anti-oxidative, and lipid-modifying properties. Chemokines and chemokine receptors are influenced/modulated by curcumin. Thus, the current review focuses on the molecular mechanisms associated with curcumin's effects on chemoattractant cytokines, as well as putting into context the many studies that have reported curcumin-mediated regulatory effects on inflammatory conditions in the organs/systems of the body (e.g., the central nervous system, liver, and cardiovascular system). Curcumin's effects on viral and bacterial infections, cancer, and adverse pregnancy outcomes are also reviewed.

Curcumin Release from Biomaterials for Enhanced Tissue Regeneration Following Injury or Disease

Curcumin, a bioactive phenol derived from turmeric, is an antioxidant, anti-inflammatory, and antibacterial molecule. Although curcumin exhibits beneficial effects in its innate form, it is highly hydrophobic, which leads to poor water solubility and, consequently, low bioavailability. The lack of bioavailability limits curcumin's effectiveness as a treatment and restricts its use in clinical applications. Furthermore, to achieve beneficial, clinically relevant results, high doses of curcumin are required for systemic administration. Many researchers have utilized biomaterial carriers, including electrospun fibers, nanoparticles, hydrogels, and composite scaffolds, to overcome curcumin's principle therapeutic limitation of low bioavailability. By using biomaterials to deliver curcumin directly to injury sites, researchers have harnessed the beneficial natural properties of curcumin while providing scaffolding to support tissue regeneration. This review will provide an in-depth overview of the literature that utilizes biomaterial delivery of curcumin for tissue regeneration in injury and disease models.

Targeting Oxidative Stress in Intracerebral Hemorrhage: Prospects of the Natural Products Approach

Intracerebral hemorrhage (ICH), the second most common subtype of stroke, remains a significant cause of morbidity and mortality worldwide. The pathological mechanism of ICH is very complex, and it has been demonstrated that oxidative stress (OS) plays an important role in the pathogenesis of ICH. Previous studies have shown that OS is a therapeutic target after ICH, and antioxidants have also achieved some benefits in the treatment of ICH. This review aimed to explore the promise of natural products therapy to target OS in ICH. We searched PubMed using the keywords “oxidative stress in intracerebral hemorrhage” and “natural products in intracerebral hemorrhage”. Numerous animal and cell studies on ICH have demonstrated the potent antioxidant properties of natural products, including polyphenols and phenolic compounds, terpenoids, alkaloids, etc. In summary, natural products such as antioxidants offer the possibility of treatment of OS after ICH. However, researchers still have a long way to go to apply these natural products for the treatment of ICH more widely in the clinic.

Quantitative and Noninvasive Detection of SAH-Related MiRNA in Cerebrospinal Fluids In Vivo Using SERS Sensors Based on Acupuncture-Based Technology

Quantitative analysis of microRNAs (miRNAs) in a noninvasive manner is of vital importance for disease diagnosis and prognosis evaluation. However, conventional strategies for realizing accurate, simple, and sensitive detection of target molecules are still a challenge, especially for miRNAs due to their low abundance and susceptibility in the complex biological environment. Here, a novel surface-enhanced Raman scattering (SERS) strategy was established for quantitative detection and monitoring of miRNA-21-5p (miR-21-5p) in living cells and in vivo cerebrospinal fluid (CSF) by applying hairpin DNA (hpDNA)-conjugated gold nanostars (GNSs) SERS probes combined with acupuncture-based technology. This strategy enabled ultrasensitive exploration toward miR-21-5p in a wide range from 1 fM to 100 pM in cell lysates. Moreover, SERS analysis facilitated the detection and long-term monitoring for in vivo miR-21-5p noninvasively. This developed strategy promises to offer a powerful method for the analysis of multiple biomolecules in single cells and living bodies.

Nanoparticles in the diagnosis and treatment of vascular aging and related diseases

Aging-induced alternations of vasculature structures, phenotypes, and functions are key in the occurrence and development of vascular aging-related diseases. Multiple molecular and cellular events, such as oxidative stress, mitochondrial dysfunction, vascular inflammation, cellular senescence, and epigenetic alterations are highly associated with vascular aging physiopathology. Advances in nanoparticles and nanotechnology, which can realize sensitive diagnostic modalities, efficient medical treatment, and better prognosis as well as less adverse effects on non-target tissues, provide an amazing window in the field of vascular aging and related diseases. Throughout this review, we presented current knowledge on classification of nanoparticles and the relationship between vascular aging and related diseases. Importantly, we comprehensively summarized the potential of nanoparticles-based diagnostic and therapeutic techniques in vascular aging and related diseases, including cardiovascular diseases, cerebrovascular diseases, as well as chronic kidney diseases, and discussed the advantages and limitations of their clinical applications.

Nanocurcumin substantially alleviates noise stress-induced anxiety-like behavior: the roles of tight junctions and NMDA receptors in the hippocampus

Environmental noise stress affects non-auditory brain regions such as the hippocampus; an area of the brain implicated in cognition and emotion. Recent experimental data indicate that dysfunction of the blood-brain barrier (BBB) and overexpression of NMDA receptors may cause anxiety. In this experiment, we evaluated the effect of nanocurcumin on anxiety-like behavior and the expression of tight junctions and NMDA receptor subunits in the hippocampus of rats exposed to traffic noise. Forty rats were assigned to control (CON), stress (ST), nanocurcumin (NC), and nanocurcumin+stress (NC+ST) groups. Anxiety-like behavior was evaluated through an elevated zero maze apparatus. The gene expression of tight junctions and NMDA receptor subunits was examined by real-time PCR in the hippocampus. Statistical analysis showed that noise exposure developed anxiety-like behavior and elevated the corticosterone level in the ST group compared to the CON group. The nanocurcumin administration decreased the stress and anxiety in the NC+ST group compared to the ST animals. While the noise stress reduced the gene expression of tight junctions occludin, claudin-5, and ZO-1, the nanocurcumin administration increased them in the NC+ST animals. Furthermore, the noise stress elevated the gene expression of the NMDA receptor subunits GRIN1 and GRIN2B. The NC+ST animals showed a modification of these subunits compared to the ST animals. Our findings showed that noise exposure promotes stress and anxiety and impairs the NMDA receptor structure and BBB integrity. The nanocurcumin treatment displayed partly restored the destructive effects of noise exposure.

The blood-brain barrier and the neurovascular unit in subarachnoid hemorrhage: molecular events and potential treatments

The response of the blood-brain barrier (BBB) following a stroke, including subarachnoid hemorrhage (SAH), has been studied extensively. The main components of this reaction are endothelial cells, pericytes, and astrocytes that affect microglia, neurons, and vascular smooth muscle cells. SAH induces alterations in individual BBB cells, leading to brain homeostasis disruption. Recent experiments have uncovered many pathophysiological cascades affecting the BBB following SAH. Targeting some of these pathways is important for restoring brain function following SAH. BBB injury occurs immediately after SAH and has long-lasting consequences, but most changes in the pathophysiological cascades occur in the first few days following SAH. These changes determine the development of early brain injury as well as delayed cerebral ischemia. SAH-induced neuroprotection also plays an important role and weakens the negative impact of SAH. Supporting some of these beneficial cascades while attenuating the major pathophysiological pathways might be decisive in inhibiting the negative impact of bleeding in the subarachnoid space. In this review, we attempt a comprehensive overview of the current knowledge on the molecular and cellular changes in the BBB following SAH and their possible modulation by various drugs and substances.

Neural stem cell therapy in conjunction with curcumin loaded in niosomal nanoparticles enhanced recovery from traumatic brain injury

Despite a great amount of effort, there is still a need for reliable treatments of traumatic brain injury (TBI). Recently, stem cell therapy has emerged as a new avenue to address neuronal regeneration after TBI. However, the environment of TBI lesions exerts negative effects on the stem cells efficacy. Therefore, to maximize the beneficial effects of stem cells in the course of TBI, we evaluated the effect of human neural stem/progenitor cells (hNS/PCs) and curcumin-loaded niosome nanoparticles (CM-NPs) on behavioral changes, brain edema, gliosis, and inflammatory responses in a rat model of TBI. After TBI, hNS/PCs were transplanted within the injury site and CM-NPs were orally administered for 10 days. Finally, the effect of combination therapy was compared to several control groups. Our results indicated a significant improvement of general locomotor activity in the hNS/PCs + CM-NPs treatment group compared to the control groups. We also observed a significant improvement in brain edema in the hNS/PCs + CM-NPs treatment group compared to the other groups. Furthermore, a significant decrease in astrogliosis was seen in the combined treatment group. Moreover, TLR4-, NF-κB-, and TNF-α- positive cells were significantly decreased in hNS/PCs + CM-NPs group compared to the control groups. Taken together, this study indicated that combination therapy of stem cells with CM-NPs can be an effective therapy for TBI.

Hydroxysafflor Yellow A Inhibits Aβ1-42-Induced Neuroinflammation by Modulating the Phenotypic Transformation of Microglia via TREM2/TLR4/NF-κB Pathway in BV-2 Cells

Hydroxysafflor yellow A (HSYA) is an extract from Carthamus tinctorius L. dry flowers (Compositae). HSYA has been shown to have neuroprotective effects on several Alzheimer's disease (AD) models. However, the exact mechanisms by which HSYA regulates neuroinflammation have still not been clarified. In this study, we investigated the mechanism by which HSYA regulates microglial activation and neuroinflammation via TREM2, and further clarified its underlying molecular mechanism. We silenced TREM2 in BV-2 cells and evaluated the expression of inflammatory markers (TNF-α, IL-1β, IL-4, IL-6, IL-10, and IL-13). The results showed that HSYA could up-regulate cell viability and improve the morphology of BV-2 cells injured by Aβ1-42. The results showed that Aβ1-42 could induce microglia to upregulate the expression of M1 markers (iNOS, IL-1β, IL-6) and downregulate M2 marker (Arg-1, IL-4, IL-10, IL-13) expression. HSYA reversed the effects of Aβ1-42 via TREM2, switching microglia from an M1 proinflammatory phenotype to an M2 anti-inflammatory phenotype. HSYA inhibited the Aβ1-42-induced activation of the TLR4/NF-κB transduction pathway by upregulating TREM2 and regulated the transcription of inflammatory cytokines via the downstream transcription factors NF-κB p65 and IκB-α. In conclusion, HSYA regulated the microglial inflammatory phenotype by regulating microglial (M1/M2) polarization in Aβ1-42-induced BV-2 cells which may be mediated by the TREM2/TLR4/NF-κB pathway.

COG133 Attenuates the Early Brain Injury Induced by Blood-Brain Barrier Disruption in Experimental Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a kind of severe hemorrhagic stroke, and early brain injury acted as one of the main causes of death and delayed neurological deficit in patients with subarachnoid hemorrhage. In this process, the function and structural integrity of the blood-brain barrier play an important role. In this study, we have observed whether the apolipoprotein E (apoE) mimetic peptide, COG133, can alleviate early brain injury after subarachnoid hemorrhage. For this purpose, an experimental subarachnoid hemorrhage model was constructed in mice and treated by intravenous injection of COG133 at a dosage of 1 mg/kg. Then, the function and integrity of the blood-brain barrier were detected, and the pyroptosis level of the neuron was determined. The results showed that COG133 could protect blood-brain barrier function and structure integrity, reduce early brain injury, and ameliorate neurological function after subarachnoid hemorrhage. In terms of molecular mechanism, COG133 inhibits blood-brain barrier destruction through the proinflammatory CypA-NF-κB-MMP9 pathway and reduces neuronal pyroptosis by inhibiting NLRP3 inflammasome activation. In conclusion, this study demonstrated that apoE-mimetic peptide, COG133, can play a neuroprotective role by protecting blood-brain barrier function and inhibiting brain cell pyroptosis to reduce early brain injury after subarachnoid hemorrhage.

Inflammaging and Brain: Curcumin and Its Beneficial Potential as Regulator of Microglia Activation

Inflammaging is a term used to describe the tight relationship between low-grade chronic inflammation and aging that occurs during physiological aging in the absence of evident infection. This condition has been linked to a broad spectrum of age-related disorders in various organs including the brain. Inflammaging represents a highly significant risk factor for the development and progression of age-related conditions, including neurodegenerative diseases which are characterized by the progressive dysfunction and degeneration of neurons in the brain and peripheral nervous system. Curcumin is a widely studied polyphenol isolated from Curcuma longa with a variety of pharmacologic properties. It is well-known for its healing properties and has been extensively used in Asian medicine to treat a variety of illness conditions. The number of studies that suggest beneficial effects of curcumin on brain pathologies and age-related diseases is increasing. Curcumin is able to inhibit the formation of reactive-oxygen species and other pro-inflammatory mediators that are believed to play a pivotal role in many age-related diseases. Curcumin has been recently proposed as a potential useful remedy against neurodegenerative disorders and brain ageing. In light of this, our current review aims to discuss the potential positive effects of Curcumin on the possibility to control inflammaging emphasizing the possible modulation of inflammaging processes in neurodegenerative diseases.

New Promising Therapeutic Avenues of Curcumin in Brain Diseases

Curcumin, the dietary polyphenol isolated from Curcuma longa (turmeric), is commonly used as an herb and spice worldwide. Because of its bio-pharmacological effects curcumin is also called "spice of life", in fact it is recognized that curcumin possesses important proprieties such as anti-oxidant, anti-inflammatory, anti-microbial, antiproliferative, anti-tumoral, and anti-aging. Neurodegenerative diseases such as Alzheimer's Diseases, Parkinson's Diseases, and Multiple Sclerosis are a group of diseases characterized by a progressive loss of brain structure and function due to neuronal death; at present there is no effective treatment to cure these diseases. The protective effect of curcumin against some neurodegenerative diseases has been proven by in vivo and in vitro studies. The current review highlights the latest findings on the neuroprotective effects of curcumin, its bioavailability, its mechanism of action and its possible application for the prevention or treatment of neurodegenerative disorders.

An Update on Antioxidative Stress Therapy Research for Early Brain Injury After Subarachnoid Hemorrhage

The main reasons for disability and death in aneurysmal subarachnoid hemorrhage (aSAH) may be early brain injury (EBI) and delayed cerebral ischemia (DCI). Despite studies reporting and progressing when DCI is well-treated clinically, the prognosis is not well-improved. According to the present situation, we regard EBI as the main target of future studies, and one of the key phenotype-oxidative stresses may be called for attention in EBI after laboratory subarachnoid hemorrhage (SAH). We summarized the research progress and updated the literature that has been published about the relationship between experimental and clinical SAH-induced EBI and oxidative stress (OS) in PubMed from January 2016 to June 2021. Many signaling pathways are related to the mechanism of OS in EBI after SAH. Several antioxidative stress drugs were studied and showed a protective response against EBI after SAH. The systematical study of antioxidative stress in EBI after laboratory and clinical SAH may supply us with new therapies about SAH.

Phenolic compounds that cross the blood-brain barrier exert positive health effects as central nervous system antioxidants

The blood-brain barrier (BBB) is a physical structure whose main function is to strictly regulate access to circulating compounds into the central nervous system (CNS). Vegetable-derived phenolic compounds have been widely studied, with numerous epidemiologic and interventional studies confirming their health-related bioactivities across multiple cells, organs and models. Phenolics are non-essential xenobiotics, and should theoretically be unable to cross the BBB. The present work summarizes current experimental evidence that reveals that not only are phenolic compounds able to cross the BBB and bioaccumulate in the brain, but there is some stereoselectivity, which suggests the presence of specific transporters that allow them to reach the brain. Some molecules cross the BBB intact, while others do so only after being biotransformed or metabolized elsewhere. Once inside the CNS, they prevent or counter oxidative stress, which maintains the molecular, cellular, structural and functional integrity of the brain, and subsequently, overall human health.

Protective mechanism of FoxO1 against early brain injury after subarachnoid hemorrhage by regulating autophagy

INTRODUCTION

Early brain injury (EBI) plays a key role in the devastating outcomes after subarachnoid hemorrhage (SAH). Autophagy and apoptosis may share a common molecular inducer that regulates the process of cell death. FoxO1, as a key regulator of neuronal autophagy which is involved in apoptosis, has not been reported in SAH rats. This work was to investigate the protective and anti-inflammatory effects of FoxO1 on EBI after SAH by regulating autophagy.

METHODS

In this study, we constructed the SAH model. In experiment I, low dose (50 μl of 1 × 10⁸  IU/ml) or high dose (50 μl of 1 × 10¹⁰  IU/ml) of FoxO1 gene overexpressed adenovirus vector was injected into the lateral ventricle of rats before SAH. In experiment II, we reported the effect of FoxO1 overexpress on nerve function recovery, oedema, BBB leakage, neuronal death in rats after SAH through autophagy regulation. Post-SAH evaluation included neurological function score, brain water content, evans blue exosmosis, pathological changes, inflammatory response and apoptosis.

RESULTS

The experiment I showed that either low or high dose of ad-FoxO1 could significantly improve nerve function, reduce cerebral water content and reduce blood-brain barrier (BBB) destruction in rats, indicating that ad-FoxO1 had a protective effect on brain injury in rats EBI after SAH. In addition, ad-FoxO1 promoted autophagy in rat hippocampal tissue, as evidenced by accumulation of LC3II/I and Beclin-1 and degradation of p62. Furthermore, ad-FoxO1 inhibited the inflammatory response and apoptosis of rat hippocampal neurons after SAH. The experiment II showed that both ad-FoxO1 and rapamycin attenuated the injury of nerve function in rats after SAH, and this synergistic effect further reduced cerebral edema and evansblue extravasation, decreased hippocampus neuronal cell apoptosis, and declined inflammatory response. However, this was contrary to the results of chloroquine. These findings suggested that FoxO1 regulated the neural function of EBI after SAH through the autophagy pathway.

CONCLUSIONS

The findings in this study was beneficial for identifying the novel therapeutic target for the treatment of SAH.

Evaluation of the protective effect of curcumin on encephalopathy caused by intrahepatic and extrahepatic damage in male rats

Objective(s):

Along with increased intracranial pressure (ICP) and brain damage, brain edema is the most common cause of death in patients with hepatic encephalopathy. Curcumin can pass the blood-brain barrier and possesses anti-inflammatory and anti-oxidant properties. This study focuses on the curcumin protective effect on intrahepatic and extrahepatic damage in the brain.

Materials and Methods:

One hundred and forty-four male Albino N-Mary rats were randomly divided into 2 main groups: intrahepatic injury group and extrahepatic cholestasis group. In intra-hepatic injury group intrahepatic damage was induced by intraperitoneal (IP) injection of acetaminophen (500 mg/kg) [19] and included four subgroups: 1. Sham, 2. Acetaminophen (APAP), 3. Normal saline (Veh) which was used as curcumin solvent, and 4. Curcumin (CMN). In extrahepatic cholestasis group intrahepatic damage was caused by common bile duct litigation (BDL) and included four subgroups: 1. Sham, 2. BDL, 3. Vehicle (Veh), and 4. Curcumin (CMN). In both groups, 72 hr after induction of cholestasis, brain water content, blood-brain barrier permeability, serum ammonia, and histopathological indicators were examined and ICP was measured every 24 hr for three days.

Results:

The results showed that curcumin reduced brain edema, ICP, serum ammonia, and blood-brain barrier permeability after extrahepatic and intrahepatic damage. The maximum effect of curcumin on ICP was observed 72 hr after the injection.

Conclusion:

According to our findings, it seems that curcumin is an effective therapeutic intervention for treating encephalopathy caused by extrahepatic and intrahepatic damage.

Evaluation of Protective Effects of Curcumin and Nanocurcumin on Aluminium Phosphide‑Induced Subacute Lung Injury in Rats: Modulation of Oxidative Stress through SIRT1/FOXO3 Signalling Pathway

OBJECTIVE

Aluminum phosphide (AlP) is widely used to protect stored food products and grains from pests and rodents. The availability of AlP, especially in Asian countries it has become a desirable factor to commit suicide. The phosphine produced from ALP is a very reactive radical and a respiratory inhibitor that causes oxidative damage. There is no dedicated antidote or effective drug to manage AlP-induced lung toxicity. The present study aims to evaluate and compare the protective effects of curcumin and nanocurcumin on ALP‑induced subacute lung injury and determine the underlying mechanism.

METHODS

Rats were exposed to AlP (2 mg/kg/day, orally)+curcumin or nanocurcumin (100 mg/kg/day, orally) for 7 days. Then rats were anesthetized and lung tissues were collected. Oxidative stress biomarkers, genes expression of antioxidant enzymes, participated genes in the SIRT1/FOXO3 pathway, and lung histopathology were assessed by biochemical and ELISA methods, Real-Time PCR analysis, and H&E staining.

RESULTS

Curcumin and nanocurcumin produced a remarkable improvement in AlP-induced lung damage through reduction of MDA, induction of antioxidant capacity (TAC, TTG) and antioxidant enzymes (CAT, GPx), modulation of histopathological changes, and up-regulation of genes expression of SIRT1, FOXO3, FOXO1 in lung tissue.

CONCLUSION

Nanocurcumin had a significantly more protective effect than curcumin to prevent AlP-induced lung injury via inhibition of oxidative stress. Nanocurcumin could be considered a suitable therapeutic choice for AlP poisoning.

Protective mechanism of Erigeron breviscapus injection on blood-brain barrier injury induced by cerebral ischemia in rats

This study investigates the protective effect of Erigeron breviscapus injection, a classic traditional Chinese medicine most typically used by Chinese minority to treat stroke, on cerebral ischemia-reperfusion injury and the related signaling pathways. Use network pharmacology methods to study the relationship between E. breviscapus (Vant.) Hand-Mazz. and ischemic stroke, predict the mechanism and active ingredients of E. breviscapus (Vant.) Hand-Mazz. in improving ischemic stroke disease. We study the protective effect of E. breviscapus injection on blood-brain barrier (BBB) injuries induced by cerebral ischemia in rats by regulating the ROS/RNS-MMPs-TJs signaling pathway. The rat model of focal cerebral ischemia-reperfusion injury has been prepared using the wire-suppository method. Firstly, the efficacy of E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid in protecting BBB injury caused by cerebral ischemia has been evaluated. Secondly, the following two methods have been used to study the mechanism of E. breviscapus injection in regulating the ROS/RNS-MMPS-TJS signaling pathway: real-time PCR and western blot for the determination of iNOS, MMP-9, claudin-5, occludin, ZO-1 mRNA and protein expression in brain tissue. We find that PI3K-Akt signaling pathway predicted by network pharmaology affects the blood-brain barrier function, so we chose the blood-brain barrier-related MMP-9, claudin-5, iNOS, occludin and ZO-1 proteins are used for research. The results of our research show that 3 drugs can reduce the rate of cerebral infarction in rats, relieve the abnormal neuroethology of rats, reduce the degree of brain tissue lesion, increase the number of the Nissl corpuscle cells and repair the neuron ultrastructure in injured rats. At the same time, it can obviously reduce the ultrastructure damage of the BBB in rats. All three drugs significantly reduced the content of Evans blue in the ischemic brain tissue caused by cerebral ischemia in rats with BBB injury. In addition, E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid can decrease the protein expression of iNOS and MMP-9 in rat ischemic brain tissue. In addition, 3,5-dicaffeoylquinic acid can increase the protein expression of claudin-5. We conclude that E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid have obvious therapeutic effects on BBB and neuron injury induced by cerebral ischemia in rats. Our results from studying the mechanism of action show that E. breviscapus injection and Scutellarin inhibited the activation of MMP-9 by inhibiting the synthesis of iNOS, 3,5-dicaffeoylquinic acid inhibits the expression and activation of MMP-9 by inhibiting the activation of iNOS and reducing the generation of free radicals, thus reducing the degradation of important cytoskeleton connexin claudin-5 in the tight junction (TJ) structure by inhibiting the expression and activation of MMP-9. Finally BBB structure integrity was protected.

Hydrogen gas post-conditioning attenuates early neuronal pyroptosis in a rat model of subarachnoid hemorrhage through the mitoKATP signaling pathway

Neuronal pyroptosis serves an important role in the progress of neurologic dysfunction following subarachnoid hemorrhage (SAH), which is predominantly caused by a ruptured aneurysm. Hydrogen gas has been previously reported to be an effective anti-inflammatory agent against ischemia-associated diseases by regulating mitochondrial function. The objective of the present study was to investigate the potential neuroprotective effects of hydrogen gas post-conditioning against neuronal pyroptosis after SAH, with specific focus on the mitochondrial ATP-sensitive K⁺ (mitoK_ATP) channels. Following SAH induction by endovascular perforation, rats were treated with inhalation of 2.9% hydrogen gas for 2 h post-perforation. Neurologic deficits, brain water content, reactive oxygen species (ROS) levels, neuronal pyroptosis, phosphorylation of ERK1/2, p38 MAPK and pyroptosis-associated proteins IL-1β and IL-18 were evaluated 24 h after perforation by a modified Garcia method, ratio of wet/dry weight, 2',7'-dichlorofluorescin diacetate, immunofluorescence and western blot assays, respectively. An inhibitor of the mitoK_ATP channel, 5-hydroxydecanoate sodium (5-HD), was used to assess the potential role of the mitoK_ATP-ERK1/2-p38 MAPK signal pathway. Hydrogen gas post-conditioning significantly alleviated brain edema and improved neurologic function, reduced ROS production and neuronal pyroptosis, suppressed the expression of IL-1β and IL-18 whilst upregulating ERK1/2 phosphorylation, but downregulated p38 MAPK activation 24 h post-SAH. These aforementioned effects neuroprotective were partially reversed by 5-HD treatment. Therefore, these observations suggest that post-conditioning with hydrogen gas ameliorated SAH-induced neuronal pyroptosis at least in part through the mitoK_ATP/ERK1/2/p38 MAPK signaling pathway.

Reactive-oxygen-species-scavenging nanomaterials for resolving inflammation

Reactive oxygen species (ROS) mediate multiple physiological functions; however, the over-accumulation of ROS causes premature aging and/or death and is associated with various inflammatory conditions. Nevertheless, there are limited clinical treatment options that are currently available. The good news is that owing to the considerable advances in nanoscience, multiple types of nanomaterials with unique ROS-scavenging abilities that influence the temporospatial dynamic behaviors of ROS in biological systems have been developed. This has led to the emergence of next-generation nanomaterial-controlled strategies aimed at ameliorating ROS-related inflammatory conditions. Accordingly, herein we reviewed recent progress in research on nanotherapy based on ROS scavenging. The underlying mechanisms of the employed nanomaterials are emphasized. Furthermore, important issues in developing cross-disciplinary nanomedicine-based strategies for ROS-based inflammatory conditions are discussed. Our review of this increasing interdisciplinary field will benefit ongoing studies and clinical applications of nanomedicine based on ROS scavenging.

Conjugated Linoleic Acid-Curcumin Attenuates Cognitive Deficits and Oxidative Stress Parameters in the Ethidium Bromide-Induced Model of Demyelination

Oxidative stress has been shown to play an important role in the pathogenesis of multiple sclerosis (MS). Curcumin (CUR), an antioxidant compound, can be a potent treatment for neurodegenerative diseases, such as MS. CUR has poor bioavailability; therefore, it is used in nanoforms to increase its bioavailability. In the present study, the effects of CUR and conjugated linoleic acid-CUR (Lino-CUR) on spatial memory and oxidative stress in a putative animal model of MS were investigated. Forty-nine adult male Wistar rats (250 ± 50 g) were randomly divided into seven groups (n = 7): control, sham, ethidium bromide (EB), CUR (20 and 40 μg/kg) + EB, and Lino-CUR (20 and 40 μg/kg) + EB groups. Following MS induction, the groups were treated for 5 consecutive days. Finally, spatial memory and levels of oxidative stress parameters were assessed. Treatment with CUR and Lino-CUR at two doses significantly improved spatial memory and reduced oxidative stress parameters in the experimental models of MS. Furthermore, the effects of high dose (40 μg/kg) of Lino-CUR were more remarkable. These findings suggest that the microinjection of CUR in its synthetic form Lino-CUR significantly ameliorated spatial memory, through the reduction of oxidative stress markers in the brain of studied animals as a rat model of MS.

Ifenprodil Improves Long-Term Neurologic Deficits Through Antagonizing Glutamate-Induced Excitotoxicity After Experimental Subarachnoid Hemorrhage

Excessive glutamate leading to excitotoxicity worsens brain damage after SAH and contributes to long-term neurological deficits. The drug ifenprodil is a non-competitive antagonist of GluN1-GluN2B N-methyl-d-aspartate (NMDA) receptor, which mediates excitotoxic damage in vitro and in vivo. Here, we show that cerebrospinal fluid (CSF) glutamate level within 48 h was significantly elevated in aSAH patients who later developed poor outcome. In rat SAH model, ifenprodil can improve long-term sensorimotor and spatial learning deficits. Ifenprodil attenuates experimental SAH-induced neuronal death of basal cortex and hippocampal CA1 area, cellular and mitochondrial Ca²⁺ overload of basal cortex, blood-brain barrier (BBB) damage, and cerebral edema of early brain injury. Using in vitro models, ifenprodil declines the high-concentration glutamate-mediated intracellular Ca²⁺ increase and cell apoptosis in primary cortical neurons, reduces the high-concentration glutamate-elevated endothelial permeability in human brain microvascular endothelial cell (HBMEC). Altogether, our results suggest ifenprodil improves long-term neurologic deficits through antagonizing glutamate-induced excitotoxicity.

Drug delivery platforms for neonatal brain injury

Hypoxic-ischemic encephalopathy (HIE), initiated by the interruption of oxygenated blood supply to the brain, is a leading cause of death and lifelong disability in newborns. The pathogenesis of HIE involves a complex interplay of excitotoxicity, inflammation, and oxidative stress that results in acute to long term brain damage and functional impairments. Therapeutic hypothermia is the only approved treatment for HIE but has limited effectiveness for moderate to severe brain damage; thus, pharmacological intervention is explored as an adjunct therapy to hypothermia to further promote recovery. However, the limited bioavailability and the side-effects of systemic administration are factors that hinder the use of the candidate pharmacological agents. To overcome these barriers, therapeutic molecules may be packaged into nanoscale constructs to enable their delivery. Yet, the application of nanotechnology in infants is not well examined, and the neonatal brain presents unique challenges. Novel drug delivery platforms have the potential to magnify therapeutic effects in the damaged brain, mitigate side-effects associated with high systemic doses, and evade mechanisms that remove the drugs from circulation. Encouraging pre-clinical data demonstrates an attenuation of brain damage and increased structural and functional recovery. This review surveys the current progress in drug delivery for treating neonatal brain injury.

Effect of inosine monophosphate dehydrogenase-1 gene polymorphisms on mycophenolate mofetil effectiveness in neuromyelitis optica spectrum disorder patients

BACKGROUND

Inosine monophosphate dehydrogenase-1 is the target of mycophenolate mofetil. This research investigated the association between the gene polymorphism of inosine monophosphate dehydrogenase-1 and effectiveness of mycophenolate mofetil therapy in neuromyelitis optica spectrum disorder patients.

METHODS

Fifty-nine neuromyelitis optica spectrum disorder patients accepted Mycophenolate Mofetil therapy for 1 year at least were divided into two groups: relapsing (n=21) and non-relapsing (n=38). Four single-nucleotide polymorphisms (SNPs: rs2228075, rs2278294, rs2288550, and rs3793165) in the inosine monophosphate dehydrogenase-1 gene were detected. Then we analyzed the allelic frequencies and the genotypes of SNPs in two groups.

RESULTS

The allelic frequency of rs2278294 distributed differently between the relapse and non-relapsing patients (P=0.03), while no significant difference found in rs2228075, rs2288550 and rs3793165 between two groups. The genotypes C/C, C/T and T/T of rs2278294 (P = 0.031) also distributed differently between the two groups. Logistic regression analysis (adjusted by optic neuritis) showed that compared to the wild genotype C/C, C/T genotype had a 9-fold protection against relapse (OR=0.111 (0.022-0.548)), and T/T genotype had a 6.7-fold protection against relapse (OR=0.149 (0.026-0.854)).

CONCLUSION

Our study provides preliminary evidence that the genotype of rs2278294 is associated with the response of neuromyelitis optica spectrum disorder patients to mycophenolate mofetil therapy. And compared to wild allelic C, the mutation to T tended to respond better to MMF.

Application Value of CTA in the Computer-Aided Diagnosis of Subarachnoid Hemorrhage of Different Origins

Subarachnoid hemorrhage (SAH) is difficult to detect because of its circulation through subarachnoid space, which leads to a high rate of missed diagnosis. Based on the above background, the purpose of this study is to study the application value of brain CT angiography (CTA) in computer-aided diagnosis of subarachnoid hemorrhage with a wide range of brain digital subtraction angiography as a gold standard. This paper collected images and related medical records of 111 patients with spontaneous subarachnoid hemorrhage receiving brain CTA and DSA examinations from February 2015 to November 2019 in the neurology department of our hospital. In contrast to the number, position, length, width, and neck width of the causative aneurysm detected by DSA, we evaluated the diagnostic results of CTA and evaluated whether there was statistical difference between the two detectives of intracranial aneurysms. The results showed that the area under ROC curve of subtraction CTA and conventional CTA was 1.000 and 0.818, respectively, which indicated that the former had better display effect on internal carotid aneurysm (AUC > 0.9), while the latter had medium value (0.7 < AUC ≤ 0.9), and the difference was statistically significant (z = 2.390, p=0.017).

The Role of Oxidative Stress in Early Brain Injury after Subarachnoid Hemorrhage

This review focuses on the problem of oxidative stress in early brain injury (EBI) after spontaneous subarachnoid hemorrhage (SAH). EBI involves complex pathophysiological mechanisms, including oxidative stress. In the first section, we describe the main sources of free radicals in EBI. There are several sources of excessive generation of free radicals from mitochondrial free radicals’ generation and endoplasmic reticulum stress, to hemoglobin and enzymatic free radicals’ generation. The second part focuses on the disruption of antioxidant mechanisms in EBI. The third section describes some newly found molecular mechanisms and pathway involved in oxidative stress after EBI. The last section is dedicated to the pathophysiological mechanisms through which free radicals mediate early brain injury.

Paeoniflorin attenuates early brain injury through reducing oxidative stress and neuronal apoptosis after subarachnoid hemorrhage in rats

Paeoniflorin is a natural monoterpene glucoside from Paeoniae Radix with neuroprotective properties. However, it is still unclear whether paeoniflorin has neuroprotective effects on subarachnoid hemorrhage (SAH). This study explores the effect of paeoniflorin on early brain injury (EBI) using rat SAH model. We found that paeoniflorin significantly improves neurological deficits, attenuates brain water content and Evans blue extravasation at 72 h after SAH. Paeoniflorin attenuates the oxidative stress following SAH as evidenced by decrease of reactive oxygen species (ROS), malondialdehyde (MDA), 3-Nitrotyrosine, and 8-Hydroxy-2-deoxy guanosine (8-OHDG) level, increase of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase activity, and up-regulates the nuclear factor erythroid‑related factor 2 (Nrf2)/heme oxygenase‑1 (HO-1) pathway. Inhibition of microglia activation and neuro-inflammatory response both contributed to paeoniflorin's protective effects. Moreover, paeoniflorin treatment significantly reduces the ratio of Bax/Bcl-2, active caspase-3/ neuronal nuclei (NeuN) and TUNEL/DAPI positive cells at 72 h following SAH. Our results indicate that paeoniflorin may attenuate early brain injury after experimental SAH.

Nano Encapsulated Curcumin: And Its Potential for Biomedical Applications

Curcumin, a yellow-colored polyphenol extracted from the rhizome of turmeric root, is commonly used as a spice and nutritional supplement. It exhibits many pharmacological activities such as anti-inflammatory, anti-bacterial, anti-cancer, anti-Alzheimer, and anti-fungal. However, the therapeutic application of curcumin is limited by its extremely low solubility in aqueous buffer, instability in body fluids, and rapid metabolism. Nano delivery system has shown excellent potential to improve the solubility, biocompatibility and therapeutic effect of curcumin. In this review, we focus on the recent development of nano encapsulated curcumin and its potential for biomedical applications.

Metal ion-responsive nanocarrier derived from phosphonated calix[4]arenes for delivering dauricine specifically to sites of brain injury in a mouse model of intracerebral hemorrhage

Primary intracerebral hemorrhage (ICH) is a leading cause of long-term disability and death worldwide. Drug delivery vehicles to treat ICH are less than satisfactory because of their short circulation lives, lack of specific targeting to the hemorrhagic site, and poor control of drug release. To exploit the fact that metal ions such as Fe²⁺ are more abundant in peri-hematomal tissue than in healthy tissue because of red blood cell lysis, we developed a metal ion-responsive nanocarrier based on a phosphonated calix[4]arene derivative in order to deliver the neuroprotective agent dauricine (DRC) specifically to sites of primary and secondary brain injury. The potential of the dauricine-loaded nanocarriers for ICH therapy was systematically evaluated in vitro and in mouse models of autologous whole blood double infusion. The nanocarriers significantly reduced brain water content, restored blood-brain barrier integrity and attenuated neurological deficits by inhibiting the activation of glial cells, infiltration by neutrophils as well as production of pro-inflammatory factors (IL-1β, IL-6, TNF-α) and matrix-metalloprotease-9. These results suggest that our dauricine-loaded nanocarriers can improve neurological outcomes in an animal model of ICH by reducing inflammatory injury and inhibiting apoptosis and ferroptosis.

Calpastatin peptide attenuates early brain injury following experimental subarachnoid hemorrhage

Calpain activation may have an important role in early brain injury (EBI) following subarachnoid hemorrhage (SAH). The present study investigated the effects of the calpastatin peptide, a cell-permeable peptide that functions as a potent inhibitor of calpain, on EBI in a rat SAH model. It was revealed that calpastatin peptide treatment significantly reduced SAH-induced body weight loss and neurological deficit at 72 h when compared with untreated SAH controls. Furthermore, the quantification of brain water content and the extravasation of Evans blue dye revealed a significant reduction in SAH-induced brain edema and blood-brain barrier permeability at 72 h due to treatment with the calpastatin peptide when compared with untreated SAH controls. Finally, calpastatin peptide treatment significantly attenuated the protein levels of Bax, cytochrome c, cleaved caspase-9 and cleaved caspase-3, and reduced the number of terminal deoxynucleotidyl transferase dUTP nick end labelling-positive cells in the basal cortex at 72 h after SAH when compared with untreated SAH controls. These results indicated that the calpastatin peptide may ameliorate EBI following SAH in rat models.

Selective mGluR1 Negative Allosteric Modulator Reduces Blood-Brain Barrier Permeability and Cerebral Edema After Experimental Subarachnoid Hemorrhage

The blood-brain barrier (BBB) disruption leads to the vasogenic brain edema and contributes to the early brain injury (EBI) after subarachnoid hemorrhage (SAH). However, the mechanisms underlying the BBB damage following SAH are poorly understood. Here we reported that the neurotransmitter glutamate of cerebrospinal fluid (CSF) was dramatically increased in SAH patients with symptoms of cerebral edema. Using the rat SAH model, we found that SAH caused the increase of CSF glutamate level and BBB permeability in EBI, intracerebroventricular injection of exogenous glutamate deteriorated BBB damage and cerebral edema, while intraperitoneally injection of metabotropic glutamate receptor 1(mGluR1) negative allosteric modulator JNJ16259685 significantly attenuated SAH-induced BBB damage and cerebral edema. In an in vitro BBB model, we showed that glutamate increased monolayer permeability of human brain microvascular endothelial cells (HBMEC), whereas JNJ16259685 preserved glutamate-damaged BBB integrity in HBMEC. Mechanically, glutamate downregulated the level and phosphorylation of vasodilator-stimulated phosphoprotein (VASP), decreased the tight junction protein occludin, and increased AQP4 expression at 72 h after SAH. However, JNJ16259685 significantly increased VASP, p-VASP, and occludin, and reduced AQP level at 72 h after SAH. Altogether, our results suggest an important role of glutamate in disruption of BBB function and inhibition of mGluR1 with JNJ16259685 reduced BBB damage and cerebral edema after SAH.

Panax notoginseng saponins suppress lipopolysaccharide-induced barrier disruption and monocyte adhesion on bEnd.3 cells via the opposite modulation of Nrf2 antioxidant and NF-κB inflammatory pathways

Dysfunction of the blood-brain barrier (BBB) is a prerequisite for the pathogenesis of many cerebral diseases. Oxidative stress and inflammation are well-known factors accounting for BBB injury. Panax notoginseng saponins (PNS), a clinical commonly used drug against cerebrovascular disease, possess efficient antioxidant and anti-inflammatory activity. In the present study, the protective effects of PNS on lipopolysaccharide (LPS)-insulted cerebral microvascular endothelial cells (bEnd.3) were assessed and the underlying mechanisms were investigated. The results showed that PNS mitigated the decrease of Trans-Endothelial Electrical Resistance, increase of paracellular permeability, and loss of tight junction proteins in bEnd.3 BBB model. Meanwhile, PNS suppressed the THP-1 monocytes adhesion on bEnd.3 monolayer. Moreover, PNS prevented the pro-inflammatory cytokines secretion and reactive oxygen species generation in bEnd.3 cells stimulated with LPS. Mechanism investigations suggested that PNS promoted the Akt phosphorylation, activated Nrf2 antioxidant signaling, and inhibited the NF-κB activation. All the effects of PNS could be abolished by PI3K inhibition at different levels. Taken together, these observations suggest that PNS may act as an extrinsic regulator that activates Nrf2 antioxidant defense system depending on PI3K/Akt and inhibits NF-κB inflammatory signaling to attenuate LPS-induced BBB disruption and monocytes adhesion on cerebral endothelial cells in vitro.

Advanced nanotherapies to promote neuroregeneration in the injured newborn brain

Neonatal brain injury affects thousands of babies each year and may lead to long-term and permanent physical and neurological problems. Currently, therapeutic hypothermia is standard clinical care for term newborns with moderate to severe neonatal encephalopathy. Nevertheless, it is not completely protective, and additional strategies to restore and promote regeneration are urgently needed. One way to ensure recovery following injury to the immature brain is to augment endogenous regenerative pathways. However, novel strategies such as stem cell therapy, gene therapies and nanotechnology have not been adequately explored in this unique age group. In this perspective review, we describe current efforts that promote neuroprotection and potential targets that are unique to the developing brain, which can be leveraged to facilitate neuroregeneration.

A window into the brain: Tools to assess pre-clinical efficacy of biomaterials-based therapies on central nervous system disorders

Therapeutic conveyance into the brain is a cardinal requirement for treatment of diverse central nervous system (CNS) disorders and associated pathophysiology. Effectual shielding of the brain by the blood-brain barrier (BBB) sieves out major proportion of therapeutics with the exception of small lipophilic molecules. Various nano-delivery systems (NDS) provide an effective solution around this obstacle owing to their small size and targeting properties. To date, these systems have been used for several pre-clinical disease models including glioma, neurodegenerative diseases and psychotic disorders. An efficacy screen for these systems involves a test battery designed to probe into the multiple facets of therapeutic delivery. Despite their wide application in redressing various disease targets, the efficacy evaluation strategies for all can be broadly grouped into four modalities, namely: histological, bio-imaging, molecular and behavioural. This review presents a comprehensive insight into all of these modalities along with their strengths and weaknesses as well as perspectives on an ideal design for a panel of tests to screen brain nano-delivery systems.

Liposomal Curcumin Enhances the Effect of Naproxen in a Rat Model of Migraine

BACKGROUND Curcumin is an antioxidant that reduces inflammation and pain. This study aimed to assess the effect of pretreatment with naproxen and liposomal curcumin compared with naproxen and curcumin solution on oxidative stress parameters and pain in a rat model of migraine. MATERIAL AND METHODS Sixty-three male Wistar rats included a control group (n=9) and a rat model of migraine (n=54) induced by intraperitoneal injection of nitroglycerin (1 mg/0.1 kg). The rat model group was divided into an untreated control group (n=9), a group pretreated with naproxen alone (2.8 mg/kg) (n=9), a group pretreated with naproxen (2.8 mg/kg) combined with curcumin solution (1 mg/0.1 kg) (n=9), a group pretreated with naproxen (2.8 mg/kg) combined with curcumin solution (2 mg/0.1 kg) (n=9), a group pretreated with naproxen (2.8 mg/kg) combined with liposomal curcumin solution (1 mg/0.1 kg) (n=9) a group pretreated with naproxen (2.8 mg/kg) combined with liposomal curcumin solution (2 mg/0.1 kg) (n=9). Spectroscopy measured biomarkers of total oxidative status and nociception was tested using an injection of 1% of formalin into the rat paw. RESULTS Expression of biomarkers of oxidative stress and enhanced nociception were significantly increased following pretreatment with combined naproxen and liposomal curcumin compared with curcumin solution or naproxen alone (P<0.001). Combined curcumin solution and naproxen were more effective at a concentration of 2 mg/0.1kg for the first nociceptive phase (P<0.005). CONCLUSIONS In a rat model of migraine, combined therapy with liposomal curcumin and naproxen showed an improved antioxidant effect and anti-nociceptive effect.