Engineered exosomes enriched with select microRNAs amplify their therapeutic efficacy for traumatic brain injury and stroke.

Traumatic brain injury (TBI) and stroke stand as prominent causes of global disability and mortality. Treatment strategies for stroke and TBI are shifting from targeting neuroprotection toward cell-based neurorestorative strategy, aiming to augment endogenous brain remodeling, which holds considerable promise for the treatment of TBI and stroke. Compelling evidence underscores that the therapeutic effects of cell-based therapy are mediated by the active generation and release of exosomes from administered cells. Exosomes, endosomal derived and nano-sized extracellular vesicles, play a pivotal role in intercellular communication. Thus, we may independently employ exosomes to treat stroke and TBI. Systemic administration of mesenchymal stem cell (MSC) derived exosomes promotes neuroplasticity and neurological functional recovery in preclinical animal models of TBI and stroke. In this mini review, we describe the properties of exosomes and recent exosome-based therapies of TBI and stroke. It is noteworthy that the microRNA cargo within exosomes contributes to their therapeutic effects. Thus, we provide a brief introduction to microRNAs and insight into their key roles in mediating therapeutic effects. With the increasing knowledge of exosomes, researchers have "engineered" exosome microRNA content to amplify their therapeutic benefits. We therefore focus our discussion on the therapeutic benefits of recently employed microRNA-enriched engineered exosomes. We also discuss the current opportunities and challenges in translating exosome-based therapy to clinical applications.

Vepoloxamer improves functional recovery in rat after traumatic brain injury: A dose-response and therapeutic window study.

Traumatic brain injury (TBI) is a major cause of death and disability worldwide. There are no effective therapies available for TBI patients. Vepoloxamer is an amphiphilic polyethylene-polypropylene-polyethylene tri-block copolymer that seals membranes and restores plasma membrane integrity in damaged cells. We previously demonstrated that treatment of TBI rats with Vepoloxamer improves functional recovery. However, additional studies are needed to potentially translate Vepoloxamer treatment from preclinical studies into clinical applications. We thus conducted a study to investigate dose-response and therapeutic window of Vepoloxamer on functional recovery of adult rats after TBI. To identify the most effective dose of Vepoloxamer, male Wistar adult rats with controlled cortical impact (CCI) injury were randomly treated with 0 (vehicle), 100, 300, or 600 mg/kg of Vepoloxamer, administered intravenously (IV) at 2 h after TBI. We then performed a therapeutic window study in which the rats were treated IV with the most effective single dose of Vepoloxamer at different time points of 2 h, 4 h, 1 day, or 3 days after TBI. A battery of cognitive and neurological tests was performed. Animals were killed 35 days after TBI for histopathological analysis. Dose-response experiments showed that Vepoloxamer at all three tested doses (100, 300, 600 mg/kg) administered 2 h post injury significantly improved cognitive functional recovery, whereas Vepoloxamer at doses of 300 and 600 mg/kg, but not the 100 mg/kg dose, significantly reduced lesion volume compared to saline treatment. However, Vepoloxamer at 300 mg/kg showed significantly improved neurological and cognitive outcomes than treatment with a dose of 600 mg/kg. In addition, our data demonstrated that the dose of 300 mg/kg of Vepoloxamer administered at 2 h, 4 h, 1 day, or 3 days post injury significantly improved neurological function compared with vehicle, whereas Vepoloxamer administered at 2 h or 4 h post injury significantly improved cognitive function compared with the 1-day and 3-day treatments, with the most robust effect administered at 2 h post injury. The present study demonstrated that Vepoloxamer improves functional recovery in a dose-and time-dependent manner, with therapeutic efficacy compared with vehicle evident even when the treatment is initiated 3 days post TBI in the rat.

Therapeutic Role of microRNAs of Small Extracellular Vesicles from Human Mesenchymal Stromal/Stem Cells in Treatment of Experimental Traumatic Brain Injury.

Mesenchymal stem/stromal cells (MSC)-derived small extracellular vesicles (sEVs) possess therapeutic potential for treatment of traumatic brain injury (TBI). The essential role of micro ribonucleic acids (miRNAs) underlying the beneficial effects of MSC-derived sEVs for treatment of TBI remains elusive. The present study was designed to investigate the role of microRNAs in sEVs from MSCs with Argonaute 2 knockdown (Ago2-KD) in neurological recovery, neuroinflammation, and neurovascular remodeling in TBI rats. Therapeutic effects of sEVs derived from naïve MSCs (naïve-sEV), MSCs transfected with a vector carrying scramble control short hairpin RNA (shRNA; vector-sEV), and MSCs transfected with a lentiviral vector-based shRNA against Ago2 to knock down Ago2 (Ago2-KD-sEV) were determined in adult male rats subjected to a moderate TBI induced by controlled cortical impact (CCI). sEVs (naïve-sEV, vector-sEV, and Ago2-KD-sEV) or vehicle (phosphate-buffered solution [PBS]) were given intravenously 1 day post-injury (PI). Multiple neurological functional tests were performed weekly PI for 5 weeks. The Morris water maze (MWM) test was performed for spatial learning and memory 31-35 days PI. All animals were euthanized 5 weeks PI and the brains were collected for analyses of lesion volume, cell loss, neurovascular remodeling, and neuroinflammation. Ago2-KD reduced global sEV miRNA levels. Compared with the vehicle treatment, both naïve-sEV and vector-sEV treatments significantly improved functional recovery, reduced hippocampal neuronal cell loss, inhibited neuroinflammation, and promoted neurovascular remodeling (angiogenesis and neurogenesis). However, Ago2-KD-sEV treatment had a significantly less therapeutic effect on all the parameters measured above than did naïve-sEV and vector-sEV treatments. The therapeutic effects of Ago2-KD-sEV were comparable to that of vehicle treatment. Our findings demonstrate that attenuation of Ago2 protein in MSCs reduces miRNAs in MSC-derived sEVs and abolishes exosome treatment-induced beneficial effects in TBI recovery, suggesting that miRNAs in MSC-derived sEVs play an essential role in reducing neuronal cell loss, inhibiting neuroinflammation, and augmenting angiogenesis and neurogenesis, as well as improving functional recovery in TBI. The findings underscore the important role of miRNAs in MSC-derived sEVs in the treatment of TBI.

A preparation strategy for protein-oriented immobilized silica magnetic beads with Spy chemistry for ligand fishing.

Due to the complexity of bioactive ingredients in biological samples, the screening of target proteins is a complex process. Herein, a feasible strategy for directing protein immobilization on silica magnetic beads for ligand fishing based on SpyTag/SpyCatcher (ST/SC)-mediated anchoring is presented. Carboxyl functional groups on the surface of silica-coated magnetic beads (SMBs) were coupled with SC using the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysulfosuccinimide method, named SC-SMBs. The green fluorescent protein (GFP), as the capturing protein model, was ST-labeled and anchored at a specific orientation onto the surface of SC-SMBs directly from relevant cell lysates via ST/SC self-ligation. The characteristics of the SC-SMBs were studied via electron microscopy, energy dispersive spectroscopy, and Fourier transform infrared spectroscopy. The spontaneity and site-specificity of this unique reaction were confirmed via electrophoresis and fluorescence analyses. Although the alkaline stability of ST-GFP-ligated SC-SMBs was not ideal, the formed isopeptide bond was unbreakable under acidic conditions (0.05 M glycine-HCl buffer, pH 1-6) for 2 h, under 20% ethanol solution within 7 days, and at most temperatures. We, therefore, present a simple and universal strategy for the preparation of diverse protein-functionalized SMBs for ligand fishing, prompting its usage on drug screening and target finding.

Preparation and identification of an anti-nicarbazin monoclonal antibody and its application in the agriculture and food industries.

Background: As a broad-spectrum drug against chicken coccidiosis, nicarbazine is widely used. The international community has made regulations and requirements on the residue limits of nicarbazine metabolites in chicken. The research reports on the detection methods of nicarbazine residues are mainly based on large-scale instruments such as high-performance liquid chromatography (HPLC), liquid chromatography-mass spectrometry-mass spectrometry (LC/MS/MS) and so on. However, in the practical monitoring and detection application, the rapid, sensitive, efficient and accurate detection of nicarbazine residues is becoming more and more urgent. Methods: This study aimed to establish an enzyme-linked immunosorbent assay (ELISA)-based method to detect nicarbazin drug residues with high sensitivity and specificity, and wide applicability. Artificial immunogens were prepared by molecular modification synthesis. Nuclear magnetic resonance (NMR) and ultraviolet analyses were conducted to confirm that the correct product was obtained. Monoclonal antibodies were acquired by immunizing mice and preparing hybridoma cells. Results: In this study, 4,4'-dinitrocarbanilide (DNC), a metabolite of nicarbazine, was synthesized and modified to make it have immunogenicity. Fifteen healthy female mice of 6-8 weeks old were immunized in three groups. The successfully immunized mice were screened by serum titer. One mouse with the highest titer was fused and cloned three times, and four positive cell lines were obtained. Nine monoclonal antibodies were obtained from mouse ascites. The best matched antigens and antibodies were screened by an ELISA chessboard method. A detection method of nicarbazine ELISA kit was developed. Our prepared anti-nicarbazin monoclonal antibody had a half-maximal inhibitory concentration (IC50) of 0.825 ng/mL, and the curve range was 0.3-24.3 ng/mL. There was no cross reaction to other six common anti-coccidiosis drugs. The recovery results showed that the fortified recovery of the chicken and duck samples ranged from 74.4-111.7%, the test results of which all met the requirements for veterinary drug residue detection. Conclusions: This method, which uses a specific antibody against the nicarbazin metabolic product DNC, enables rapid quantitative detection. Our new ELISA-based method should facilitate the development of assays to monitor and detect agricultural and veterinary drug residues.

Generation and Characterization of an Anti-diclazuril Monoclonal Antibody and Development of a Diagnostic Enzyme-Linked Immunosorbent Assay for Poultry.

An anti-diclazuril monoclonal antibody (mAb) was developed for use in enzyme-linked immunosorbent assay (ELISA)-based detection of diclazuril with high sensitivity and specificity, which can be used to measure anti-coccidial drug residues. The anti-diclazuril mAb had a half-maximal inhibitory concentration of 0.449-0.517 ng/mL. The mAb cross-reactivity with toltrazuril, toltrazuril 18 sulfone, clozaril, monesin, madurmycin, and salinomycin was very minimal (< 0.1%). The detection limit of the ELISA using this mAb was 0.10 ng/mL and the sensitivity was 0.05 ng/mL. A standard curve generated in the range of 0.05-16.2 ng/mL had a linear correlation coefficient value of ≥ 0.99. The average recoveries of diclazuril from chicken and duck samples ranged from 85.0 to 102.5%.Intra- and inter-assay coefficients of variation ranged from 5.9 to 8.5% and 9.2 to 12.6%, respectively. Using the International Immunogenetics Information System®, the VH domain of the mAb was found to be encoded by an IGHV3 family gene and had the following complementarity determining region (CDR) sequences: GFTFSRY (CDR1), SRGGS (CDR2), and GDDNYAFAY (CDR3). The VL domain was encoded by an IGKV1 family gene and had the following CDR sequences: KSSQSLLNSRTRKNYLA (CDR1), WASTRES (CDR2), and KQSYNLHT (CDR3). This study provides a method to generate anti-diclazuril mAbs and determine their variable region sequences. The diagnostic ELISA developed using this mAb may drive additional studies on the monitoring and detection of food and veterinary drug residues.

Preparation and properties of N-glycosylated chitosan/polyvinyl alcohol hydrogels for use in wound dressings.

Chitosan and its derivatives show potent biocompatibility, biodegradability, antimicrobial activity, hemostatic effects, and wound healing properties. Their application in wound dressings has garnered substantial research interest. In this work, we prepared a drug-loaded hydrogel by mixing N-glycosylated chitosan with polyvinyl alcohol (PVA), followed by loading of ofloxacin. A 2:1 volume ratio of chitosan to PVA was found to be optimal based on swelling and water evaporation rates. The slow-drug-release performance of the blended hydrogel was best when the ofloxacin loading was 5.0%. The ofloxacin-loaded hydrogel shows excellent antimicrobial properties in vitro and wound healing ability in an in vivo rabbit full-thickness excision wound model. The chitosan/PVA blended hydrogel has great potential for use in wound dressings and sustained drug release.

A preparation strategy for protein-oriented immobilized silica magnetic beads with Spy chemistry for ligand fishing / 药物分析学报

Due to the complexity of bioactive ingredients in biological samples,the screening of target proteins is a complex process.Herein,a feasible strategy for directing protein immobilization on silica magnetic beads for ligand fishing based on SpyTag/SpyCatcher(ST/SC)-mediated anchoring is presented.Carboxyl functional groups on the surface of silica-coated magnetic beads(SMBs)were coupled with SC using the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysulfosuccinimide method,named SC-SMBs.The green fluorescent protein(GFP),as the capturing protein model,was ST-labeled and anchored at a specific orientation onto the surface of SC-SMBs directly from relevant cell lysates via ST/SC self-ligation.The characteristics of the SC-SMBs were studied via electron microscopy,energy dispersive spectroscopy,and Fourier transform infrared spectroscopy.The spontaneity and site-specificity of this unique reaction were confirmed via electrophoresis and fluorescence analyses.Although the alkaline stability of ST-GFP-ligated SC-SMBs was not ideal,the formed isopeptide bond was unbreakable under acidic conditions(0.05 M glycine-HCl buffer,pH 1-6)for 2 h,under 20％ethanol solution within 7 days,and at most temperatures.We,therefore,present a simple and universal strategy for the preparation of diverse protein-functionalized SMBs for ligand fishing,prompting its usage on drug screening and target finding.

MiR-17-92 Cluster-Enriched Exosomes Derived from Human Bone Marrow Mesenchymal Stromal Cells Improve Tissue and Functional Recovery in Rats after Traumatic Brain Injury.

Exosomes play an important role in intercellular communication by delivering microribonucleic acids (miRNAs) to recipient cells. Previous studies have demonstrated that multi-potent mesenchymal stromal cell (MSC)-derived exosomes improve functional recovery after experimental traumatic brain injury (TBI). This study was performed to determine efficacy of miR-17-92 cluster-enriched exosomes (Exo-17-92) harvested from human bone marrow MSCs transfected with a miR-17-92 cluster plasmid in enhancing tissue and neurological recovery compared with exosomes derived from MSCs transfected with an empty plasmid vector (Exo-empty) for treatment of TBI. Adult male rats underwent a unilateral moderate cortical contusion. Animals received a single intravenous injection of miR-17-92 cluster-enriched exosomes (100 µg/rat, approximately 3.75x1011 particles, Exo-17-92) or control exosomes (100 µg/rat, Exo-empty) or Vehicle (phosphate-buffered solution) one day after injury. A battery of neurological functional tests was performed weekly after TBI for five weeks. Spatial learning and memory were measured on days 31-35 after TBI using the Morris water maze test. All animals were sacrificed five weeks after injury. Their brains were processed for histopathological and immunohistochemical analyses of lesion volume, cell loss, angiogenesis, neurogenesis, and neuroinflammation. Compared with Vehicle, both Exo-17-92 and Exo-empty treatments significantly improved sensorimotor and cognitive function, reduced neuroinflammation and hippocampal neuronal cell loss, promoted angiogenesis and neurogenesis without altering the lesion volume. Moreover, Exo-17-92 treatment exhibited a significantly more robust therapeutic effect on improvement in functional recovery by reducing neuroinflammation and cell loss, enhancing angiogenesis and neurogenesis than did Exo-empty treatment. Exosomes enriched with miR-17-92 cluster have a significantly better effect on improving functional recovery after TBI compared with Exo-empty, likely by reducing neuroinflammation and enhancing endogenous angiogenesis and neurogenesis. Engineering specific miRNA in exosomes may provide a novel therapeutic strategy for management of unilateral moderate cortical contusion TBI.

MRI detection of impairment of glymphatic function in rat after mild traumatic brain injury.

We investigated the effect of mild traumatic brain injury (mTBI) on the glymphatic pathway using contrast-enhanced magnetic resonance imaging (CE-MRI) and quantified with kinetic parameters obtained from an advanced two-compartment model. mTBI was induced in male Wistar rats using a closed head impact. Animals with and without mTBI (n = 7/group) underwent the identical MRI protocol 10-weeks post-injury, including T2-weighted imaging and 3D T1-weighted imaging with intra-cisterna magna injection of contrast agent (Gd-DTPA). The parameters of infusion rate, clearance rate and clearance time constant, characterizing the kinetic features of glymphatic tracer transport in a living brain, were quantified in multiple brain tissue regions. In the majority of examined regions, our quantification demonstrated significantly reduced infusion and clearance rates, and significantly increased clearance time constant in the mTBI animals compared to the healthy controls. These data indicate that mTBI induces chronic changes in influx and efflux of contrast agent and glymphatic pathway dysfunction. While the reduced efficiency of glymphatic function after mTBI was apparent in brain, regional evaluation revealed heterogeneous glymphatic effects of the mTBI in different anatomical regions. The suppression of glymphatic function, rather than the presence of focal lesions, indicates a persistent injury of the brain after mTBI. Thus, dynamic CE-MRI in conjunction with advanced kinetic analysis may offer a useful methodology for an objective assessment and confirmatory diagnosis of mTBI.

Mesenchymal Stem Cell-Derived Exosomes Improve Functional Recovery in Rats After Traumatic Brain Injury: A Dose-Response and Therapeutic Window Study.

Background. Mesenchymal stem cell (MSC)-derived exosomes play a critical role in regenerative medicine. Objective. To determine the dose- and time-dependent efficacy of exosomes for treatment of traumatic brain injury (TBI). Methods. Male rats were subjected to a unilateral moderate cortical contusion. In the dose-response study, animals received a single intravenous injection of exosomes (50, 100, 200 µg per rat) or vehicle, with treatment initiated at 1 day after injury. In the therapeutic window study, animals received a single intravenous injection of 100 µg exosomes or vehicle starting at 1, 4, or 7 days after injury. Neurological functional tests were performed weekly after TBI for 5 weeks. Spatial learning was measured on days 31 to 35 after TBI using the Morris water maze test. Results. Compared with the vehicle, regardless of the dose and delay in treatment, exosome treatment significantly improved sensorimotor and cognitive function, reduced hippocampal neuronal cell loss, promoted angiogenesis and neurogenesis, and reduced neuroinflammation. Exosome treatment at 100 µg per rat exhibited a significant therapeutic effect compared with the 50- or 200-µg exosome groups. The time-dependent exosome treatment data demonstrated that exosome treatment starting at 1 day post-TBI provided a significantly greater improvement in functional and histological outcomes than exosome treatments at the other 2 delayed treatments. Conclusions. These results indicate that exosomes have a wide range of effective doses for treatment of TBI with a therapeutic window of at least 7 days postinjury. Exosomes may provide a novel therapeutic intervention in TBI.

An update on Wnt signaling pathway in cancer.

Wnt signaling involves many aspects of development, cell biology and physiology. Mutations in the Wnt gene can lead to abnormal embryonic development and cancer formation, including various aspects that affect proliferation, morphogenesis, and differentiation. The occurrence and development of tumors is a complex process involving multiple factors. The Wnt signaling pathway participates in this process as an anti-tumor target by activating multiple gene transcriptions. The emergence of Wnt pathway inhibitors and targeted drugs has opened up a new world of cancer treatment. This review focuses on the mechanism of action of the Wnt signaling pathway in different cancers. Secondly, we have organized and introduced the latest Wnt anti-tumor drugs.

Randomized controlled trial of Cerebrolysin's effects on long-term histological outcomes and functional recovery in rats with moderate closed head injury.

OBJECTIVE: The authors previously demonstrated that Cerebrolysin is effective for treatment of mild closed head injury (CHI) when administered 4 hours after injury. The aim of this study was to determine Cerebrolysin's effects on functional and histological outcomes in rats subjected to moderate CHI. METHODS: In this randomized, blinded, and vehicle-controlled preclinical trial, male adult Wistar rats subjected to moderate CHI received either Cerebrolysin treatment at a dose of 2.5 ml/kg (n = 13) or vehicle (saline, n = 13) intraperitoneally administered daily for 10 days, starting at 4 hours after injury. Animals were subjected to cognitive and sensorimotor functional tests at multiple time points, and they were killed 3 months after injury. The brains were processed for analyses of neuronal cell loss, amyloid precursor protein, axonal damage, and neurogenesis. RESULTS: Compared with rats treated with vehicle (saline), rats treated with Cerebrolysin had significantly increased numbers of neuroblasts and newborn mature neurons in the dentate gyrus (DG) and attenuated amyloid precursor protein accumulation and axonal damage in various brain regions, as well as decreased neuronal loss in the DG and cornu ammonis 3 (CA3) region of the hippocampus (p < 0.05). Global testing using generalized estimating equations showed a significant beneficial effect of Cerebrolysin treatment on sensorimotor functional outcomes from 1 day to 3 months after injury compared to that of saline treatment (p < 0.05). Compared with vehicle-treated rats, Cerebrolysin-treated rats showed significantly and robustly improved long-term (up to 3 months) cognitive functional recovery, as measured by social interaction, Morris water maze, novel object recognition, and odor recognition tests. In the Cerebrolysin-treated rats there were significant correlations between multiple histological outcomes and functional recovery evident 3 months after moderate CHI, as indicated by Pearson partial correlation analyses. CONCLUSIONS: The authors' findings demonstrate that Cerebrolysin treatment significantly improves long-term functional and histological outcomes in rats with moderate CHI, with functional outcomes significantly correlated with histological indices of neuroplasticity and neuroprotection. These data indicate that Cerebrolysin may be useful for the treatment of moderate CHI.

A structure-activity relationship of a thrombin-binding aptamer containing LNA in novel sites.

In this report, structural characterization, aptamer stability and thrombin of a new modified thrombin-ligand complex binding aptamer (TBA) containing anti-guanine bases and a loop position locked nucleic acid (LNA) are presented. NMR, circular dichroic spectroscopy and molecular modeling were used to characterize the three-dimensional structure of two G-quadruplexes. LNA-modification of the anti-guanosines yields G-quadruplexes that show affinity and inhibitory activity toward thrombin, whereas LNA-modification of a thymine nucleotide in the TGT loop increases the thermal stability of TBA. As assessed by denatured PAGE electrophoresis, all modified aptamers display an increase in environmental stability. The prothrombin time assay and fibrinogen assay showed that the aptamers still had good inhibitory activity, and 15 of them had the longest PT time. Therefore, the LNA modification is well suited to improve the physicochemical and biological properties of the native thrombin-binding aptamer.

A Biotransformation Process for Production of Genistein from Sophoricoside by a Strain of Rhizopus oryza.

Genistein is known to have multiple biological activities and has great potential for use as a preventative medicine and in disease treatment. Genistein can be extracted from plants, but also can be obtained from its glycoside form, sophoricoside, which is more abundant in some plants. Biotransformation by unpurified microbial enzymes has the advantage of low cost and is a preferred method for production of natural compounds. This study isolated a strain of Rhizopus oryzae that could produce ß-glucosidase, which efficiently hydrolyzes sophoricoside into genistein, from an enrichment culture of the dried fruits of Sophora japonica. After the composition of enzyme-producing medium and biotransformation conditions were optimized, a genistein yield of 85.6% was obtained after 24 h in a shake-flask biotransformation at pH 7.0 using an initial substrate concentration of 1 g/L. The developed process provides an alternative method for production of genistein, and would be suitable for scale-up production in the pharmaceutical industry.

Mesenchymal Stem Cell-Derived Exosomes Provide Neuroprotection and Improve Long-Term Neurologic Outcomes in a Swine Model of Traumatic Brain Injury and Hemorrhagic Shock.

Combined traumatic brain injury (TBI) and hemorrhagic shock (HS) remains a leading cause of preventable death worldwide. Mesenchymal stem cell-derived exosomes have demonstrated promise in small animal models of neurologic injury. To investigate the effects of exosome treatment in a clinically realistic large animal model, Yorkshire swine underwent TBI and HS. Animals were maintained in shock for 2 h before resuscitation with normal saline (NS). Animals were then resuscitated either with NS (3 × volume of shed blood) or with the same volume of NS with delayed exosome administration (1 × 1013 particles/4 mL) (n = 5/cohort). Exosomes were administered 9 h post-injury, and on post-injury days (PID) 1, 5, 9, and 13. Neurologic severity scores (NSS) were assessed for 30 days, and neurocognitive functions were objectively measured. Exosome-treated animals had significantly lower NSS (p < 0.05) during the first five days of recovery. Exosome-treated animals also had a significantly shorter time to complete neurologic recovery (NSS = 0) compared with animals given NS alone (days to recovery: NS = 16.8 ± 10.6; NS + exosomes = 5.6 ± 2.8; p = 0.03). Animals treated with exosomes initiated neurocognitive testing earlier (days to initiation: NS = 9.6 ± 0.5 vs. NS + exosomes = 4.2 ± 0.8; p = 0.008); however, no difference was seen in time to mastery of tasks. In conclusion, treatment with exosomes attenuates the severity of neurologic injury and allows for faster neurologic recovery in a clinically realistic large animal model of TBI and HS.

A Small Molecule Spinogenic Compound Enhances Functional Outcome and Dendritic Spine Plasticity in a Rat Model of Traumatic Brain Injury.

The tetra (ethylene glycol) derivative of benzothiazole aniline (SPG101) has been shown to improve dendritic spine density and cognitive memory in the triple transgenic mouse model of Alzheimer disease (AD) when administered intraperitoneally. The present study was designed to investigate the therapeutic effects of SPG101 on dendritic spine density and morphology and sensorimotor and cognitive functional recovery in a rat model of traumatic brain injury (TBI) induced by controlled cortical impact (CCI). Young adult male Wistar rats with CCI were randomly divided into the following two groups (n = 7/group): (1) Vehicle, and (2) SPG101. SPG101 (30 mg/kg) dissolved in vehicle (1% dimethyl sulfoxide in phosphate buffered saline) or Vehicle were intraperitoneally administered starting at 1 h post-injury and once daily for the next 34 days. Sensorimotor deficits were assessed using a modified neurological severity score and adhesive removal and foot fault tests. Cognitive function was measured by Morris water maze, novel object recognition (NOR), and three-chamber social recognition tests. The animals were sacrificed 35 days after injury, and their brains were processed for measurement of dendritic spine density and morphology using ballistic dye labeling. Compared with the vehicle treatment, SPG101 treatment initiated 1 h post-injury significantly improved sensorimotor functional recovery (days 7-35, p < 0.0001), spatial learning (days 32-35, p < 0.0001), NOR (days 14 and 35, p < 0.0001), social recognition (days 14 and 35, p < 0.0001). Further, treatment significantly increased dendritic spine density in the injured cortex (p < 0.05), decreased heterogeneous distribution of spine lengths in the injured cortex and hippocampus (p < 0.0001), modifications that are associated with the promotion of spine maturation in these brain regions. In summary, treatment with SPG101 initiated 1 h post-injury and continued for an additional 34 days improves both sensorimotor and cognitive functional recovery, indicating that SPG101 acts as a spinogenic agent and may have potential as a novel treatment of TBI.

Cerebrolysin Reduces Astrogliosis and Axonal Injury and Enhances Neurogenesis in Rats After Closed Head Injury.

BACKGROUND: Cerebrolysin is a neuropeptide preparation with neuroprotective and neurotrophic properties. Our previous study demonstrates that cerebrolysin significantly improves functional recovery in rats after mild traumatic brain injury (mTBI). OBJECTIVE: To determine histological outcomes associated with therapeutic effects of cerebrolysin on functional recovery after TBI. METHODS: In this prospective, randomized, blinded, and placebo-controlled study, adult Wistar rats with mild TBI induced by a closed head impact were randomly assigned to one of the cerebrolysin dose groups (0.8, 2.5, 7.5 mL/kg) or placebo, which were administered 4 hours after TBI and then daily for 10 consecutive days. Functional tests assessed cognitive, behavioral, motor, and neurological performance. Study end point was day 90 after TBI. Brains were processed for histological tissue analyses of astrogliosis, axonal injury, and neurogenesis. RESULTS: Compared with placebo, cerebrolysin significantly reduced amyloid precursor protein accumulation, astrogliosis, and axonal damage in various brain regions and increased the number of neuroblasts and neurogenesis in the dentate gyrus. There was a significant dose effect of cerebrolysin on functional outcomes at 3 months after injury compared with saline treatment. Cerebrolysin at a dose of ⩾0.8 mL/kg significantly improved cognitive function, whereas at a dose of ⩾2.5 mL/kg, cerebrolysin also significantly improved sensorimotor function at various time points. There were significant correlations between multiple histological and functional outcomes 90 days after mTBI. CONCLUSIONS: Our findings demonstrate that cerebrolysin reduces astrogliosis and axonal injury and promotes neurogenesis, which may contribute to improved functional recovery in rats with mTBI.

Prospective, randomized, blinded, and placebo-controlled study of Cerebrolysin dose-response effects on long-term functional outcomes in a rat model of mild traumatic brain injury.

Using a prospective, randomized, blinded, placebo-controlled protocol, the authors demonstrated that Cerebrolysin at doses of 0.8-7.5 ml/kg, administered 4 hours after injury and then once daily for a total of 10 consecutive days, improves long-term functional outcomes in a rat model of mild closed head injury; a 2.5-ml/kg dose was identified as optimal. These findings suggest that Cerebrolysin has the potential to treat mild traumatic brain injury, the incidence of which is high without effective treatments.

Construction and application of an electrochemical biosensor based on an endotoxin aptamer.

An electrochemical biosensor that used an aptamer as a biological element was constructed to detect endotoxin. Biolayer interferometry was used to obtain the affinity constant of an aptamer for lipopolysaccharide, which had an equilibrium dissociation constant of 22.9 nM. The amine-terminated aptamer was then assembled on a gold electrode surface using 3-mercaptopropionic acid as an intermediate linker. The modification of the gold electrode was confirmed by cyclic voltammetry and electrochemical impedance spectroscopy. In the range of 0.001-1 EU/mL, the increase in electron transfer resistance of the biosensor was linear with the logarithmic value of the endotoxin concentration. The constructed biosensor exhibits sensitivity and a low limit of detection.