Expression profile of circular RNAs in blood samples of Northern Chinese males with intracerebral hemorrhage shows downregulation of hsa-circ-0090829.

Circular RNAs (circRNAs) are involved in several neurological disorders; however, the mechanisms underlying their involvement remain to be clarified. We attempted to explore the expression profiles of circRNAs and their potential functions and mechanisms in the pathogenesis of intracerebral hemorrhage (ICH) in Northern Chinese males. The microarray results showed that 50 circRNAs were significantly upregulated, while 194 circRNAs were significantly downregulated in ICH patients compared with healthy controls (p < 0.05). After bioinformatics analysis, a circRNA-microRNA-messenger RNA network and a protein-protein interaction network were constructed. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed that the neurotrophin signaling pathway, long-term potentiation, and the mitogen-activated protein kinase pathway are potentially implicated in ICH pathophysiology. The quantitative real-time polymerase chain reaction results revealed that hsa-circ-0090829 was significantly downregulated in ICH. The receiver operating characteristic curve analysis showed that the area under the curve of hsa-circ-0090829 between ICH and healthy controls was 0.807. Furthermore, the dual-luciferase assay showed that hsa-circ-0090829 sponged miR-526b-5p. This study reports the altered expression of circRNAs and identifies the potential functions of these circRNAs in ICH. Our results may facilitate further mechanistic research on circRNAs in ICH and provide probable novel diagnostic biomarkers and therapeutic targets for ICH.

Study of the relationship among biomarkers, cell and tissue of glioma through Raman spectroscopy.

Glioma is the most common brain tumors with high mortality and recurrence rates. Currently, the diagnosis methods for glioma are mainly based on tissue level, cellular level and biomarker level. In this paper, the characteristics of biomarkers (γ-aminobutyric acid and matrix mtalloproteinses-2), U87MG glioma cell and tissue were studied based on Raman spectroscopy, respectively. The results showed that the γ-aminobutyric acid concentration exhibited a linear relation with the intensity of characteristic peaks in 800-1600 cm-1 region, whereas the spectral baseline increased with the increasing of sample concentration in 200-700 cm-1 region. The Raman characteristics of matrix mtalloproteinses-2 in 20-1800 cm-1 region was investigated. Especially, it is demonstrated that the matrix mtalloproteinses-2 showed sixteen low-wavenumber Raman peaks in the range of 20-300 cm-1. Moreover, the U87MG glioma cell showed seven different Raman characteristic peaks in 600-1800 cm-1 region. Compared with the normal tissue, the Raman intensity of tumor tissue showed apparent intensity differences in 300-1800 cm-1, where the intensity changes of these Raman peaks were related to the reducing of the lipid metabolic pathways, and increase of the RNA in tumor tissue region. Furthermore, it is found that the Raman spectra of U87MG glioma cell and tumor tissue had corresponding peaks in the Raman spectra of the liquid γ-aminobutyric acid and matrix mtalloproteinses-2. It is suggested that the γ-aminobutyric acid and matrix mtalloproteinses-2 contributed to the formation and growth of glioma cell and tissue. Thus, Raman spectroscopy not only can diagnose glioma at the biomarkers, cellular and tissue level, but also analyze the relationship among the three. Furthermore, the results provided a physical marker for the detection of glioma in clinically.

Hippocampal HDAC5-mediated histone acetylation underlies stress susceptibility in mice exposed to chronic social defeat stress.

Chronic stress leads to social avoidance and anhedonia in susceptible individuals, a phenomenon that has been observed in both human and animal models. Nevertheless, the underlying molecular mechanisms underpinning stress susceptibility and resilience remain largely unclear. There is growing evidence that epigenetic histone deacetylase (HDAC) mediated histone acetylation is involved in the modulation of depressive-related behaviors. We hypothesized that histone deacetylase 5 (HDAC5), which is associated with stress-related behaviors and antidepressant response, may play a vital role in the susceptibility to chronic stress. In the current study, we detected the levels of HDAC5 and acetylation of histone 4 (H4) in the hippocampus subsequent to chronic social defeat stress (CSDS) in C57BL/6J mice. We found that CSDS induces a notable increase in HDAC5 expression, concomitant with a reduction in the acetylation of histone H4 at lysine 12 (H4K12) in the hippocampus of susceptible mice. Meanwhile, intrahippocampal infusion of HDAC5 shRNA or HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) both reversed the depression susceptibility in susceptible mice that subjected to CSDS. Furthermore, HDAC5 overexpression was sufficient to induce depression susceptibility following microdefeat stress, accompanied by a significant reduction in H4K12 level within the hippocampus of mice. Additionally, the Morris water maze (MWM) results indicated that neither CSDS nor HDAC5 exerted significant effects on spatial memory function in mice. Taken together, these investigations indicated that HDAC5-modulated histone acetylation is implicated in regulating the depression susceptibility, and may be serve as potential preventive targets for susceptible individuals.

A global survey of bicarbonate stress-induced pre-mRNA alternative splicing in soybean via integrative analysis of Iso-seq and RNA-seq.

Alternative splicing (AS) plays important roles in modulating environmental stress responses in plants. However, little is known about the functions of bicarbonate-induced AS in cultivated soybean (Glycine max L. Merr.). In this study, we combined PacBio isoform sequencing (Iso-seq) and Illumina RNA sequencing (RNA-seq) to elucidate the bicarbonate-induced AS events in soybean root and leaf tissues. Compared to RNA-seq, Iso-seq identified more novel genes and transcripts, as well as more AS events, indicating that Iso-seq is more efficient in AS detection. Combining these two technologies, we found that intron retention (IR) is the most frequent AS event type. We identified a total of 913 and 1974 bicarbonate stress-responsive differentially alternative spliced genes (DAGs) in soybean leaves and roots respectively, from our RNA-seq results. Additionally, we determined a transcription factor (GmNTL9) and a splicing factor (GmRSZ22), and validated their roles in bicarbonate stress response by AS. Overall, our study opens an avenue for evaluating plant AS regulatory networks, and the obtained global landscape of alternative splicing provides valuable insights into the AS-mediated bicarbonate-responsive mechanisms in plant species.

The Roles of Obesity and ASB4 in Preeclampsia Pathogenesis.

Preeclampsia is a complex pregnancy-related hypertensive disorder which poses significant risks for both maternal and fetal health. Preeclampsia affects 5-8% of pregnancies in the United States, causing a significant public health and economic burden. Despite extensive research, the etiology and pathogenesis of preeclampsia remain elusive, but have been correlated with maternal conditions such as obesity. In recent decades, the incidence of preeclampsia increased along with the prevalence of obesity among women of reproductive age. Maternal obesity has been shown to negatively affect pregnancy in almost all aspects. However, the precise mechanisms by which obesity influences preeclampsia are unclear. Ankyrin repeat and SOCS Box Containing protein 4 (ASB4) is an E3 ubiquitin ligase that can promote the degradation of a wide range of target proteins. ASB4-null mice display a full spectrum of preeclampsia-like phenotypes during pregnancy including hypertension, proteinuria, and decreased litter size. Furthermore, maternal obesity induced by a high-fat diet aggravates preeclampsia-like phenotypes in pregnant mice lacking ASB4. Variants in the ASB4 gene have been associated with obesity in humans, and a functional connection between the ASB4 gene and obesity has been established in mice. This review discusses the connections between preeclampsia, obesity, and ASB4.

The Highly Sensitive Refractive Index Sensing of Seawater Based on a Large Lateral Offset Mach-Zehnder Interferometer.

A novel fiber sensor for the refractive index sensing of seawater based on a Mach-Zehnder interferometer has been demonstrated. The sensor consisted of a single-mode fiber (SMF)-no-core fiber (NCF)-single-mode fiber structure (shortened to an SNS structure) with a large lateral offset spliced between the two sections of a multimode fiber (MMF). Optimization studies of the multimode fiber length, offset SNS length, and vertical axial offset distance were performed to improve the coupling efficiency of interference light and achieve the best extinction ratio. In the experiment, a large lateral offset sensor was prepared to detect the refractive index of various ratios of saltwater, which were used to simulate seawater environments. The sensor's sensitivity was up to -13,703.63 nm/RIU and -13,160 nm/RIU in the refractive index range of 1.3370 to 1.3410 based on the shift of the interference spectrum. Moreover, the sensor showed a good linear response and high stability, with an RSD of only 0.0089% for the trough of the interference in air over 1 h.

Downregulation of Ripk1 and Nsf mediated by CRISPR-CasRx ameliorates stroke volume and neurological deficits after ischemia stroke in mice.

Necroptosis is implicated in the pathogenesis of ischemic stroke. However, the mechanism underlying the sequential recruitment of receptor-interacting protein kinase 1 (RIPK1) and N-ethylmaleimide-sensitive fusion ATPase (NSF) in initiating necroptosis remains poorly understood, and the role of NSF in ischemic stroke is a subject of controversy. Here, we utilized a recently emerging RNA-targeting CRISPR system known as CasRx, delivered by AAVs, to knockdown Ripk1 mRNA and Nsf mRNA around the ischemic brain tissue. This approach resulted in a reduction in infarct and edema volume, as well as an improvement in neurological deficits assessed by Bederson score, RotaRod test, and Adhesive removal test, which were achieved by RIPK1/receptor-interacting protein kinase 3/mixed lineage kinase domain-like protein signaling pathway involved in neuronal necroptosis. In conclusion, the downregulation of Ripk1 mRNA and Nsf mRNA mediated by CRISPR-CasRx holds promise for future therapeutic applications aimed at ameliorating cerebral lesions and neurological deficits following the ischemic stroke.

High-sensitivity THz-ATR imaging of cerebral ischemia in a rat model.

The fast label-free detection of the extent and degree of cerebral ischemia has been the difficulty and hotspot for precise and accurate neurosurgery. We experimentally demonstrated that the fresh cerebral tissues at different ischemic stages within 24 hours can be well distinguished from the normal tissues using terahertz (THz) attenuated total reflection (ATR) imaging system. It was indicated that the total reflectivity of THz wave for ischemic cerebral tissues was lower than that for normal tissues. Especially, compared to the images stained with 2,3,5-triphenyl tetrazolium chloride (TTC), the ischemic tissues can be detected using THz wave with high sensitivity as early as the ischemic time of 2.5 hours, where THz images showed the ischemic areas became larger and diffused as the ischemic time increasing. Furthermore, the THz spectroscopy of cerebral ischemic tissues at different ischemic times was obtained in the range of 0.5-2.0 THz. The absorption coefficient of ischemic tissue increased with the increase of ischemic time, whereas the refractive index decreased with prolonging the ischemic time. Additionally, it was found from hematoxylin and eosin (H&E) staining microscopic images that, with the ischemic time increasing, the cell size and cell density of the ischemic tissues decreased, whereas the intercellular substance of the ischemic tissues increased. The result showed that THz recognition mechanism of the ischemia is mainly based on the increase of intercellular substance, especially water content, which has a stronger impact on absorption of THz wave than that of cell density. Thus, THz imaging has great potential for recognition of cerebral ischemia and it may become a new method for intraoperative real-time guidance, recognition in situ, and precise excision.

Advancing MicroRNA Detection: Enhanced Biotin-Streptavidin Dual-Mode Phase Imaging Surface Plasmon Resonance Aptasensor.

MicroRNAs (miRNAs) are novel tumor biomarkers owing to their important physiological functions in cell communication and the progression of multiple diseases. Due to the small molecular weight, short sequence length, and low concentration levels of miRNA, miRNA detection presents substantial challenges, requiring the advancement of more refined and sensitive techniques. There is an urgent demand for the development of a rapid, user-friendly, and sensitive miRNA analysis method. Here, we developed an enhanced biotin-streptavidin dual-mode phase imaging surface plasmon resonance (PI-SPR) aptasensor for sensitive and rapid detection of miRNA. Initially, we evaluated the linear sensing range for miRNA detection across two distinct sensing modalities and investigated the physical factors that influence the sensing signal in the aptamer-miRNA interaction within the PI-SPR aptasensor. Then, an enhanced biotin-streptavidin amplification strategy was introduced in the PI-SPR aptasensor, which effectively reduced the nonspecific adsorption by 20% and improved the limit of detection by 548 times. Furthermore, we have produced three types of tumor marker chips, which utilize the rapid sensing mode (less than 2 min) of PI-SPR aptasensor to achieve simultaneous detection of multiple miRNA markers in the serum from clinical cancer patients. This work not only developed a new approach to detect miRNA in different application scenarios but also provided a new reference for the application of the biotin-streptavidin amplification system in the detection of other small biomolecules.

Coffee Ring Effect Enhanced Surface Plasmon Resonance Imaging Biosensor via 2-λ Fitting Detection Method.

SPR biosensors have been extensively used for investigating protein-protein interactions. However, in conventional surface plasmon resonance (SPR) biosensors, detection is limited by the Brownian-motion-governed diffusion process of sample molecules in the sensor chip, which makes it challenging to detect biomolecule interactions at ultra-low concentrations. Here, we propose a highly sensitive SPR imaging biosensor which exploits the coffee ring effect (CRE) for in situ enrichment of molecules on the sensing surface. In addition, we designed a wavelength modulation system utilizing two LEDs to reduce the system cost and enhance the detection speed. Furthermore, a detection limit of 213 fM is achieved, which amounts to an approximately 365 times improvement compared to traditional SPR biosensors. With further development, we believe that this SPR imaging system with high sensitivity, less sample consumption, and faster detection speed can be readily applied to ultra-low-concentration molecular detection and interaction analysis.

Endothelial Nitric Oxide synthase (eNOS) in Preeclampsia: An Update.

Preeclampsia (PE) is a common pregnancy-related hypertensive disorder and is a leading cause of maternal and perinatal morbidity and mortality. The incidence of PE and its associated health care costs have been increasing in the United States over the past three decades. Pregnancies complicated by PE put both the mother and child at increased risk for chronic illnesses such as cardiovascular disease, cerebrovascular disease, and cognitive impairment later in life. To date, there is no effective treatment for PE and the etiology of PE is largely unknown. While human epidemiological studies have established an association between various genetic factors and PE, a causative link between genes associated with PE and PE development has been difficult to establish. Human studies have shown that variants in eNOS (endothelial nitric oxide synthase, also known as NOS3) gene are associated with PE, and animal experimental studies have provided evidence to show the potential functional connection between the eNOS gene and PE. Here we review several studies that investigated the role of eNOS in PE, as well as studies that described how manipulating the eNOS/NO pathway could aid in disease intervention.

Associations of liver function with plasma biomarkers for Alzheimer's Disease.

BACKGROUND: Blood-based biomarkers for Alzheimer's disease (AD) are promising to be used in clinical settings. The liver is an important degradation organ of the body. Whether liver function affects the levels of AD biomarkers needs to be studied. OBJECTIVE: To investigate the associations between liver function and the plasma levels of AD biomarkers. METHODS: We conducted an ADNI cohort-based cross-sectional study. Thirteen liver function markers commonly used in clinical settings were analyzed: total protein (TP), albumin (AL), globulin (GL), AL/GL ratio (A/G), total bilirubin (TB), direct bilirubin (DB), indirect bilirubin (IB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), AST/ALT ratio, alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and γ-glutamyltransferase (GGT). Liquid chromatography-tandem mass spectrometry was used to detect the plasma Aß42 and Aß40 concentrations. Single Molecule array technique was used to measure the plasma p-tau181 and NfL concentrations. We used linear regression models to analyze the associations between liver function markers and the levels of AD plasma biomarkers. RESULTS: ALP was positively associated with the levels of plasma Aß42 (ß = 0.16, P = 0.018) and Aß40 (ß = 0.21, P = 0.004). LDH was positively associated with the levels of plasma p-tau181 (ß = 0.09, P = 0.022). While NfL was correlated with multiple liver function markers, including AL, A/G, ALT, AST/ALT, and LDH. CONCLUSION: Liver function was associated with the plasma levels of AD biomarkers. It needs to consider the potential influence of liver function on the reference ranges and the interpretation of results for AD biomarkers before clinical use.

Quantitative electroencephalography (qEEG), apolipoprotein A-I (APOA-I), and apolipoprotein epsilon 4 (APOE ɛ4) alleles for the diagnosis of mild cognitive impairment and Alzheimer's disease.

INTRODUCTION: Alzheimer's disease (AD) is the most common type of dementia. Amnestic mild cognitive impairment (aMCI), a pre-dementia stage is an important stage for early diagnosis and intervention. This study aimed to investigate the diagnostic value of qEEG, APOA-I, and APOE ɛ4 allele in aMCI and AD patients and found the correlation between qEEG (Delta + Theta)/(Alpha + Beta) ratio (DTABR) and different cognitive domains. METHODS: All participants were divided into three groups: normal controls (NCs), aMCI, and AD, and all received quantitative electroencephalography (qEEG), neuropsychological scale assessment, apolipoprotein epsilon 4 (APOE ɛ4) alleles, and various blood lipid indicators. Different statistical methods were used for different data. RESULTS: The cognitive domains except executive ability were all negatively correlated with DTABR in different brain regions while executive ability was positively correlated with DTABR in several brain regions, although without statistical significance. The consequences confirmed that the DTABR of each brain area were related to MMSE, MoCA, instantaneous memory, and the language ability (p < 0.05), and the DTABR in the occipital area was relevant to all cognitive domains (p < 0.01) except executive function (p = 0.272). Also, occipital DTABR was most correlated with language domain when tested by VFT with a moderate level (r = 0.596, p < 0.001). There were significant differences in T3, T5, and P3 DTABR between both AD and NC and aMCI and NCs. As for aMCI diagnosis, the maximum AUC was achieved when using T3 combined with APOA-I and APOE ε4 (0.855) and the maximum AUC was achieved when using T5 combined with APOA-I and APOE ε4 (0.889) for AD diagnosis. CONCLUSION: These findings highlight that APOA-I, APOE ɛ4, and qEEG play an important role in aMCI and AD diagnosis. During AD continuum, qEEG DTABR should be taken into consideration for the early detection of AD risk.

Knockout of SWS2 in zebrafish (Danio rerio) reveals its roles in feeding and phototactic behaviors.

Common ancestor of vertebrates had four cone opsin subfamilies to obtain color vision: ultraviolet-sensitive (SWS1), blue-sensitive (SWS2), middle wavelength sensitive (RH2) and long wavelength sensitive (LWS). Nevertheless, eutherian mammals had lost the SWS2 and RH2 opsins during their nocturnal lifestyle. Many studies had demonstrated the role of SWS1 and LWS cones in feeding, mate choice and skin pigment cell formation. However, the role of SWS2 and RH2 cones remain elusive. In the present study, we used an ideal model visual system, zebrafish, which still have the four cone opsins, to generate a SWS2 knockout zebrafish line. Through various behavioral test, we found that sws2-/- zebrafish larvae exhibited increased food intake compared with WT. Additionally, there were significantly increased the gene expression of phototransduction pathways in sws2-/- zebrafish larvae. Compared to WT, mutant zebrafish showed weaker phototaxis of red light and changed sensitivity of yellow, red and blue lights. But both mutant and WT zebrafish preferred the red light than other wavelengths of light. Taken together, we proposed that SWS2 cone is not necessary for feeding and phototaxis in zebrafish.

Narrow linewidth and wideband tunable continuous-wave terahertz generator based on difference frequency generation with DAST crystal.

A narrow linewidth and wideband tunable continuous-wave terahertz generator with DAST crystal has been demonstrated in this paper. Two narrow-linewidth CW fiber lasers were used as the pump sources for difference frequency generation. The terahertz wave can be continuously tunable in the range of 1.1-3 THz. The maximum output power of 2.79nW was obtained at 2.568 THz. The linewidth of the output THz wave was estimated to be 56.5 MHz by fitting transmission spectrum of CO gas at 450 Pa pressure around 80.52 cm-1 with the Vogit gas model. Furthermore, the output spectra at room temperature and pressure was in good agreement with the air absorption lines in Hitran database. Moreover, the narrower absorption characteristic spectrum of 2-Deoxy-D-Glucose sample has been obtained through the spectrum measurements. Therefore, it could promote the practical prospect of tunable CW-THz source, which will have good potential in THz high-precision spectroscopic detection and multispectral imaging.

Identification of novel diagnostic panel for mild cognitive impairment and Alzheimer's disease: findings based on urine proteomics and machine learning.

BACKGROUND: Alzheimer's disease is a prevalent disease with a heavy global burden. Proteomics is the systematic study of proteins and peptides to provide comprehensive descriptions. Aiming to obtain a more accurate and convenient clinical diagnosis, researchers are working for better biomarkers. Urine is more convenient which could reflect the change of disease at an earlier stage. Thus, we conducted a cross-sectional study to investigate novel diagnostic panels. METHODS: We firstly enrolled participants from China-Japan Friendship Hospital from April 2022 to November 2022, collected urine samples, and conducted an LC-MS/MS analysis. In parallel, clinical data were collected, and clinical examinations were performed. After statistical and bioinformatics analyses, significant risk factors and differential urinary proteins were determined. We attempt to investigate diagnostic panels based on machine learning including LASSO and SVM. RESULTS: Fifty-seven AD patients, 43 MCI patients, and 62 CN subjects were enrolled. A total of 3366 proteins were identified, and 608 urine proteins were finally included in the analysis. There were 33 significantly differential proteins between the AD and CN groups and 15 significantly differential proteins between the MCI and CN groups. AD diagnostic panel included DDC, CTSC, EHD4, GSTA3, SLC44A4, GNS, GSTA1, ANXA4, PLD3, CTSH, HP, RPS3, CPVL, age, and APOE ε4 with an AUC of 0.9989 in the training test and 0.8824 in the test set while MCI diagnostic panel included TUBB, SUCLG2, PROCR, TCP1, ACE, FLOT2, EHD4, PROZ, C9, SERPINA3, age, and APOE ε4 with an AUC of 0.9985 in the training test and 0.8143 in the test set. Besides, diagnostic proteins were weakly correlated with cognitive functions. CONCLUSIONS: In conclusion, the procedure is convenient, non-invasive, and useful for diagnosis, which could assist physicians in differentiating AD and MCI from CN.

Altered Visual Function in Short-Wave-Sensitive 1 (sws1) Gene Knockout Japanese Medaka (Oryzias latipes) Larvae.

Visual perception plays a crucial role in foraging, avoiding predators, mate selection, and communication. The regulation of color vision is largely dependent on opsin, which is the first step in the formation of the visual transduction cascade in photoreceptor cells. Short-wave-sensitive 1 (sws1) is a visual pigment that mediates short-wavelength light transduction in vertebrates. The depletion of sws1 resulted in increased M-opsin in mice. However, there is still no report on the visual function of sws1 in teleost fish. Here, we constructed the sws1 knockout medaka using CRISPR/Cas9 technology. The 6 dph (days post-hatching) medaka sws1-/- larvae exhibited significantly decreased food intake and total length at the first feeding stage, and the mRNA levels of orexigenic genes (npy and agrp) were significantly upregulated after feeding. The swimming speed was significantly reduced during the period of dark-light transition stimulation in the sws1-mutant larvae. Histological analysis showed that the thickness of the lens was reduced, whereas the thickness of the ganglion cell layer (GCL) was significantly increased in sws1-/- medaka larvae. Additionally, the deletion of sws1 decreased the mRNA levels of genes involved in phototransduction (gnb3b, grk7a, grk7b, and pde6c). We also observed increased retinal cell apoptosis and oxidative stress in sws1 knockout medaka larvae. Collectively, these results suggest that sws1 deficiency in medaka larvae may impair visual function and cause retinal cell apoptosis, which is associated with the downregulation of photoconduction expression and oxidative stress.

Calcium Imaging Characterize the Neurobiological Effect of Terahertz Radiation in Zebrafish Larvae.

(1) Objective: To explore the neurobiological effects of terahertz (THz) radiation on zebrafish larvae using calcium (Ca2+) imaging technology. (2) Methods: Zebrafish larvae at 7 days post fertilization (dpf) were exposed to THz radiation for 10 or 20 min; the frequency was 2.52 THz and the amplitude 50 mW/cm2. The behavioral experiments, neural Ca2+ imaging, and quantitative polymerase chain reaction (qPCR) of the dopamine-related genes were conducted following the irradiation. (3) Results: Compared with the control group, the behavioral experiments demonstrated that THz radiation significantly increased the distance travelled and speed of zebrafish larvae. In addition, the maximum acceleration and motion frequency were elevated in the 20 min radiation group. The neural Ca2+ imaging results indicated a substantial increase in zebrafish neuronal activity. qPCR experiments revealed a significant upregulation of dopamine-related genes, such as drd2b, drd4a, slc6a3 and th. (4) Conclusion: THz radiation (2.52 THz, 50 mW/cm2, 20 min) upregulated dopamine-related genes and significantly enhanced neuronal excitability, and the neurobiological effect of THz radiation can be visualized using neural Ca2+ imaging in vivo.

Ursolic Acid Ameliorated Neuronal Damage by Restoring Microglia-Activated MMP/TIMP Imbalance in vitro.

Purpose: The oxygen and glucose deprivation-reoxygenation (OGDR) model is widely used to evaluate ischemic stroke and cerebral ischemia-reperfusion (I/R) injury in vitro. Excessively activated microglia produce pro-inflammatory mediators such as matrix metalloproteinases [MMPs] and their specific inhibitors, tissue inhibitors of metalloproteinases [TIMPs], causing neuronal damage. Ursolic acid (UA) acts as a neuroprotective agent in the rat middle cerebral artery occlusion/reperfusion (MCAO/R) model keeping the MMP/TIMP balance with underlying mechanisms unclear. Our study used OGDR model to determine whether and how UA reduces neuronal damage by reversing MMP/TIMP imbalance caused by microglia in I/R injury in vitro. Methods: SH-SY5Y cells were first cultured with 95% N2 and 5% CO2 and then cultivated regularly for OGDR model. Cell viability was tested for a proper UA dose. We established a co-culture system with SH-SY5Y cells and microglia-conditioned medium (MCM) stimulated by lipopolysaccharide (LPS) and interferon-gamma (IFNγ). MMP9 and TIMP1 levels were measured with ELISA assay to confirm the UA effect. We added recombinant MMP9 (rMMP9) and TIMP1 neutralizing antibody (anti-TIMP1) for reconfirmation. Transmission electron microscopy was used to observe cell morphology, and flow cytometry and Annexin V-FITC and PI labeling for apoptotic conditions. We further measured the calcium fluorescence intensity in SH-SY5Y cells. Results: The MCM significantly reduced cell viability of SH-SY5Y cells after OGDR (p<0.01), which was restored by UA (0.25 µM) (p<0.05), whereas lactate dehydrogenase activity, intraneuronal Ca2+ concentration, and apoptosis-related indexes were showed significant improvement after UA treatment (p<0.01). UA corrected the MMP/TIMP imbalance by decreasing MMP9 expression and increasing TIMP1 expression in the co-culture system (p<0.01) and the effects of UA on SH-SY5Y cells were mitigated by the administration of rMMP9 and anti-TIMP1 (p<0.01). Conclusion: We demonstrated that UA inhibited microglia-induced neuronal cell death in an OGDR model of ischemic reperfusion injury by stabilizing the MMP9/TIMP1 imbalance.

Serum-based Raman spectroscopic diagnosis of blast-induced brain injury in a rat model.

The diagnosis of blast-induced traumatic brain injury (bTBI) is of paramount importance for early care and clinical therapy. Therefore, the rapid diagnosis of bTBI is vital to the treatment and prognosis in clinic. In this paper, we reported a new strategy for label-free bTBI diagnosis through serum-based Raman spectroscopy. The Raman spectral characteristics of serum in rat were investigated at 3 h, 24 h, 48 h and 72 h after mild and moderate bTBIs. It has been demonstrated that both the position and intensity of Raman characteristic peaks exhibited apparent differences in the range of 800-3000cm-1 compared with control group. It could be inferred that the content, structure and interaction of biomolecules in the serum were changed after blast exposure, which might help to understand the neurological syndromes caused by bTBI. Furthermore, the control group, mild and moderate bTBIs at different times (a total of 9 groups) were automatically classified by combining principal component analysis and four machine learning algorithms (quadratic discriminant analysis, support vector machine, k-nearest neighbor, neural network). The highest classification accuracy, sensitivity and precision were up to 95.4%, 95.9% and 95.7%. It is suggested that this method has great potential for high-sensitive, rapid, and label-free diagnosis of bTBI.