PHLDA1 contributes to hypoxic ischemic brain injury in neonatal rats via inhibiting FUNDC1-mediated mitophagy.

Hypoxia-ischemia (HI) is one of the main causes of neonatal brain injury. Mitophagy has been implicated in the degradation of damaged mitochondria and cell survival following neonatal brain HI injury. Pleckstrin homology-like domain family A member 1 (PHLDA1) plays vital roles in the progression of various disorders including the regulation of oxidative stress, the immune responses and apoptosis. In the present study we investigated the role of PHLDA1 in HI-induced neuronal injury and further explored the mechanisms underlying PHLDA1-regulated mitophagy in vivo and in vitro. HI model was established in newborn rats by ligation of the left common carotid artery plus exposure to an oxygen-deficient chamber with 8% O2 and 92% N2. In vitro studies were conducted in primary hippocampal neurons subjected to oxygen and glucose deprivation/-reoxygenation (OGD/R). We showed that the expression of PHLDA1 was significantly upregulated in the hippocampus of HI newborn rats and in OGD/R-treated primary neurons. Knockdown of PHLDA1 in neonatal rats via lentiviral vector not only significantly ameliorated HI-induced hippocampal neuronal injury but also markedly improved long-term cognitive function outcomes, whereas overexpression of PHLDA1 in neonatal rats via lentiviral vector aggravated these outcomes. PHLDA1 knockdown in primary neurons significantly reversed the reduction of cell viability and increase in intracellular reactive oxygen species (ROS) levels, and attenuated OGD-induced mitochondrial dysfunction, whereas overexpression of PHLDA1 decreased these parameters. In OGD/R-treated primary hippocampal neurons, we revealed that PHLDA1 knockdown enhanced mitophagy by activating FUNDC1, which was abolished by FUNDC1 knockdown or pretreatment with mitophagy inhibitor Mdivi-1 (25 µM). Notably, pretreatment with Mdivi-1 or the knockdown of FUNDC1 not only increased brain infarct volume, but also abolished the neuroprotective effect of PHLDA1 knockdown in HI newborn rats. Together, these results demonstrate that PHLDA1 contributes to neonatal HI-induced brain injury via inhibition of FUNDC1-mediated neuronal mitophagy.

LncRNA-mir3471-limd1 regulatory network plays critical roles in HIBD.

The purpose of this study was to identify the target genes of tcon_00044595, elucidate its activation site, and provide novel insights into the pathogenesis and treatment of neonatal hypoxic-ischemic brain damage (HIBD). Through homologous blast analysis, we identified predicted target sequences in the neighboring regions of the long non-coding RNA (lncRNA) tcon_00044595, suggesting that limd1 is its target gene. Starbase was utilized to identify potential candidate microRNAs associated with the lncRNA. The interaction between the candidate microRNAs and limd1 was investigated and validated using various experimental methods including in vitro cell culture, cell transfection, dual fluorescence reporter detection system, and real-time PCR. Homology alignment analysis revealed that the lncRNA tcon_00044595 exhibited a 246 bp homologous sequence at the 3' end of the adjacent limd1 gene, with a conservation rate of 68%. Analysis conducted on Starbase online identified three potential microRNA candidates: miR-3471, miR-883a-5p, and miR-214-3p. Intracellular expression of the limd1 gene was significantly down-regulated upon transfection with miR-3471, while the other two microRNAs did not produce noticeable effects. Luciferase reporter assays identified two interaction sites (UTR-1, UTR-2) between miR-3471 and the limd1 3'UTR, with UTR-1 exhibiting a strong influence. Further CCK8 assay indicated a protective role of miR-3471 during low oxygen stroke in HIBD. The potential regulatory relationship between lncRNA (tcon_00044595), miR-3471, and the target gene limd1 suggests their involvement in the occurrence and development of HIBD, providing new insights for investigating the underlying mechanisms and exploring targeted therapeutic approaches for HIBD.

Suppression of Microglial ERO1a Alleviates Inflammation and Enhances the Efficacy of Rehabilitative Training After Ischemic Stroke.

Microglia mediated inflammation plays a crucial role in cellular events and functional recovery post ischemic stroke. In the current study, we profiled the proteome changes of microglia treated with oxygen and glucose deprivation (OGD). Bioinformatics analysis identified that differentially expressed proteins (DEPs) were enriched in pathways associated with oxidate phosphorylation and mitochondrial respiratory chain at both 6h and 24h post OGD. We next focused on one validated target named endoplasmic reticulum oxidoreductase 1 alpha (ERO1a) to study its role in stroke pathophysiology. We showed that over-expression of microglial ERO1a exacerbated inflammation, cell apoptosis and behavioral outcomes post middle cerebral artery occlusion (MCAO). In contrast, suppression of microglial ERO1a significantly reduced activation of both microglia and astrocyte, along with cell apoptosis. Furthermore, knocking down microglial ERO1a improved the efficacy of rehabilitative training and enhanced the mTOR activity in spared corticospinal neurons. Our study provided novel insights into the identification of therapeutic targets and the design of rehabilitative protocols to treat ischemic stroke and other traumatic CNS injuries.

Adipose-derived mesenchymal stem cells combined with platinum nanoparticles accelerate fracture healing in a rat tibial fracture model.

Background: At present, bone union delay or failure remains challenging for clinicians. It has been reported that adipose-derived mesenchymal stem cells (ADMSCs) offer a promising way to promote bone fracture healing. In recent years, nanomaterials have been applied in regenerative medicine. This study aimed to investigate whether ADMSCs combined with platinum nanoparticles (PtNPs) could further improve fracture healing on the basis of ADMSCs. Methods: ADMSCs were co-cultured with PtNPs in vitro to investigate the effect of PtNPs on the differentiation of ADMSCs. Twenty Sprague-Dawley (SD) rats were randomly divided into four groups (with five rats in each group). The left tibias of all rats were fractured. Phosphate-buffered saline (PBS), PtNPs, ADMSC, and ADMSC mixed with PtNPs were then injected into the fracture sites based on the group classifications. The fracture was monitored by X-ray immediately after the fracture and on days 14 and 28 post-fracture. The tibias of the rats were subsequently harvested after the last X-ray and evaluated by micro computed tomography (micro-CT), histological analysis, and immunohistochemical detection. Results: PtNPs significantly enhanced the osteogenic differentiation of ADMSCs in vitro. On days 14 and 28 post-fracture, the radiographic score of the ADMSC + PtNPs group was higher than that of the ADMSC group, the score of the ADMSC group was higher than that of the PtNPs and control groups, and there was no significant difference between the PtNPs and control groups. Micro-CT confirmed that combined ADMSCs with PtNPs were more effective than using ADMSCs alone in promoting fracture healing. The histological and immunohistochemical results further supported this conclusion. Conclusions: Our findings demonstrated that PtNPs could promote osteogenic differentiation of ADMSC in vitro. ADMSCs combined with PtNPs could accelerate fracture healing further in vivo and are a promising a potential method for the treatment of fracture healing.

Profiling Temporal Changes of the Pineal Transcriptomes at Single Cell Level Upon Neonatal HIBD.

Neonatal hypoxic-ischemic brain damage (HIBD) often results in various neurological deficits. Among them, a common, yet often neglected, symptom is circadian rhythm disorders. Previous studies revealed that the occurrence of cysts in the pineal gland, an organ known to regulate circadian rhythm, is associated with circadian problems in children with HIBD. However, the underlying mechanisms of pineal dependent dysfunctions post HIBD remain largely elusive. Here, by performing 10x single cell RNA sequencing, we firstly molecularly identified distinct pineal cell types and explored their transcriptome changes at single cell level at 24 and 72 h post neonatal HIBD. Bioinformatic analysis of cell prioritization showed that both subtypes of pinealocytes, the predominant component of the pineal gland, were mostly affected. We then went further to investigate how distinct pineal cell types responded to neonatal HIBD. Within pinealocytes, we revealed a molecularly defined ß to α subtype conversion induced by neonatal HIBD. Within astrocytes, we discovered that all three subtypes responded to neonatal HIBD, with differential expression of reactive astrocytes markers. Two subtypes of microglia cells were both activated by HIBD, marked by up-regulation of Ccl3. Notably, microglia cells showed substantial reduction at 72 h post HIBD. Further investigation revealed that pyroptosis preferentially occurred in pineal microglia through NLRP3-Caspase-1-GSDMD signaling pathway. Taken together, our results delineated temporal changes of molecular and cellular events occurring in the pineal gland following neonatal HIBD. By revealing pyroptosis in the pineal gland, our study also provided potential therapeutic targets for preventing extravasation of pineal pathology and thus improving circadian rhythm dysfunction in neonates with HIBD.

Predictive value of early amplitude integrated electroencephalogram (aEEG) in sleep related problems in children with perinatal hypoxic-ischemia (HIE).

BACKGROUND: While great attention has been paid to motor and cognitive impairments in children with neonatal Hypoxic-Ischemic Encephalopathy (HIE), sleep related circadian rhythm problems, although commonly present, are often neglected. Subsequently, no early clinical indicators have been reported to correlate with sleep-related circadian dysfunction during development. METHODS: In this study, we first analyzed patterns of the amplitude integrated electroencephalogram (aEEG) in a cohort of newborns with various degrees of HIE. Next, during follow-ups, we collected information of sleep and circadian related problems in these patients and performed correlation analysis between aEEG parameters and different sleep/circadian disorders. RESULTS: A total of 101 neonates were included. Our results demonstrated that abnormal aEEG background pattern is significantly correlated with circadian rhythmic (r = 0.289, P = 0.01) and breathing issues during sleep (r = 0.237, P = 0.037). In contrast, the establishment of sleep-wake cycle (SWC) showed no correlation with sleep/circadian problems. Detailed analysis showed that summation of aEEG score, along with low base voltage (r = 0.272, P = 0.017 and r = -0.228, P = 0.048, respectively), correlates with sleep circadian problems. In contrast, background pattern (BP) score highly correlates with sleep breathing problem (r = 0.319, P = 0.004). CONCLUSION: Abnormal neonatal aEEG pattern is correlated with circadian related sleep problems. Our study thus provides novel insights into predictive values of aEEG in sleep-related circadian problems in children with HIE.

The role of pineal microRNA-325 in regulating circadian rhythms after neonatal hypoxic-ischemic brain damage.

Circadian rhythm disorder is a common, but often neglected, consequence of neonatal hypoxic-ischemic brain damage (HIBD). However, the underlying molecular mechanisms remain largely unknown. We previously showed that, in a rat model of HIBD, up-regulation of microRNA-325 (miR-325) in the pineal gland is responsible for the suppression of Aanat, a key enzyme involved in melatonin synthesis and circadian rhythm regulation. To better understand the mechanism by which miR-325 affects circadian rhythms in neonates with HIBD, we compared clinical samples from neonates with HIBD and samples from healthy neonates recruited from the First Affiliated Hospital of Soochow University (Dushuhu Branch) in 2019. We found that circulating miR-325 levels correlated positively with the severity of sleep and circadian rhythm disorders in neonates with HIBD. Furthermore, a luciferase reporter gene assay revealed that LIM homeobox 3 (LHX3) is a novel downstream target of miR-325. In addition, in miR-325 knock-down mice, the transcription factor LHX3 exhibited an miR-325-dependent circadian pattern of expression in the pineal gland. We established a neonatal mouse model of HIBD by performing double-layer ligation of the left common carotid artery and exposing the pups to a low-oxygen environment for 2 hours. Lhx3 mRNA expression was significantly down-regulated in these mice and partially rescued in miR-325 knockout mice subjected to the same conditions. Finally, we showed that improvement in circadian rhythm-related behaviors in animals with HIBD was dependent on both miR-325 and LHX3. Taken together, our findings suggest that the miR-325-LHX3 axis is responsible for regulating circadian rhythms and provide novel insights into the identification of potential therapeutic targets for circadian rhythm disorders in patients with neonatal HIBD. The clinical trial was approved by Institutional Review Board of Children's Hospital of Soochow University (approval No. 2015028) on July 20, 2015. Animal experiments were approved by Animal Care and Use Committee, School of Medicine, Soochow University, China (approval No. XD-2016-1) on January 15, 2016.

TP53-induced glycolysis and apoptosis regulator alleviates hypoxia/ischemia-induced microglial pyroptosis and ischemic brain damage.

Our previous studies have demonstrated that TP53-induced glycolysis and apoptosis regulator (TIGAR) can protect neurons after cerebral ischemia/reperfusion. However, the role of TIGAR in neonatal hypoxic-ischemic brain damage (HIBD) remains unknown. In the present study, 7-day-old Sprague-Dawley rat models of HIBD were established by permanent occlusion of the left common carotid artery followed by 2-hour hypoxia. At 6 days before induction of HIBD, a lentiviral vector containing short hairpin RNA of either TIGAR or gasdermin D (LV-sh_TIGAR or LV-sh_GSDMD) was injected into the left lateral ventricle and striatum. Highly aggressively proliferating immortalized (HAPI) microglial cell models of in vitro HIBD were established by 2-hour oxygen/glucose deprivation followed by 24-hour reoxygenation. Three days before in vitro HIBD induction, HAPI microglial cells were transfected with LV-sh_TIGAR or LV-sh_GSDMD. Our results showed that TIGAR expression was increased in the neonatal rat cortex after HIBD and in HAPI microglial cells after oxygen/glucose deprivation/reoxygenation. Lentivirus-mediated TIGAR knockdown in rats markedly worsened pyroptosis and brain damage after hypoxia/ischemia in vivo and in vitro. Application of exogenous nicotinamide adenine dinucleotide phosphate (NADPH) increased the NADPH level and the glutathione/oxidized glutathione ratio and decreased reactive oxygen species levels in HAPI microglial cells after oxygen/glucose deprivation/reoxygenation. Additionally, exogenous NADPH blocked the effects of TIGAR knockdown in neonatal HIBD in vivo and in vitro. These findings show that TIGAR can inhibit microglial pyroptosis and play a protective role in neonatal HIBD. The study was approved by the Animal Ethics Committee of Soochow University of China (approval No. 2017LW003) in 2017.

[Role of microglial pyroptosis in hypoxic-ischemic brain damage].

OBJECTIVE: To investigate the role of microglial pyroptosis in hypoxic-ischemic brain damage. METHODS: An oxygen-glucose deprivation/reoxygenation (OGD/R) model of rat microglial cells were cultured in vitro. Western blot was used to measure the expression of the pyroptosis-related proteins caspase-1, interleukin-1ß (IL-1ß), and N-terminal gasdermin D (GSDMD-N) at 0, 1, 3, 6, 12, and 24 hours after OGD/R. After the microglial cells were transfected with lentivirus-mediated silenced gasdermin D (GSDMD), immunofluorescence assay and Western blot were used to measure the transfection rate of GSDMD. Microglial cell lines were divided into three groups: normal control, negative control, and LV-sh_GSDMD (lentivirus-mediated GSDMD silencing). CCK-8 assay and LDH kit were used to observe the effect of GSDMD silencing on the viability and toxicity of microglial cells at 24 hours after OGD/R. Western blot was used to observe the effect of GSDMD silencing on the levels of caspase-1, GSDMD-N, and IL-1ß in the microglial cells at 24 hours after OGD/R. RESULTS: The expression levels of the pyroptosis-related proteins caspase-1, GSDMD-N, and IL-1ß in microglial cells were upregulated since 0 hour after OGD/R and reached the peak levels at 24 hours. A microglial cell model of lentivirus-mediated GSDMD silencing was successfully constructed. At 24 hours after OGD/R, compared with the normal control group, the GSDMD silencing group had a significant increase in the cell viability and a significant reduction in the cytotoxicity (P<0.05), as well as significant reductions in the protein expression levels of caspase-1, GSDMD-N, and IL-1ß in microglial cells (P<0.05). CONCLUSIONS: Lentivirus silencing of the key substrate protein for pyroptosis GSDMD can alleviate hypoxic-ischemic brain damage, suggesting that microglial pyroptosis aggravates hypoxic-ischemic brain damage.

Knocking down TRPM2 expression reduces cell injury and NLRP3 inflammasome activation in PC12 cells subjected to oxygen-glucose deprivation.

Transient receptor potential melastatin 2 (TRPM2) is an important ion channel that represents a potential target for treating injury caused by cerebral ischemia. However, it is unclear whether reducing TRPM2 expression can help repair cerebral injury, and if so what the mechanism underlying this process involves. This study investigated the protective effect of reducing TRPM2 expression on pheochromocytoma (PC12) cells injured by oxygen-glucose deprivation (OGD). PC12 cells were transfected with plasmid encoding TRPM2 shRNAS, then subjected to OGD by incubation in glucose-free medium under hypoxic conditions for 8 hours, after which the cells were allowed to reoxygenate for 24 hours. Apoptotic cells, mitochondrial membrane potentials, reactive oxygen species levels, and cellular calcium levels were detected using flow cytometry. The relative expression of C-X-C motif chemokine ligand 2 (CXCL2), NACHT, LRR, and PYD domain-containing protein 3 (NALP3), and caspase-1 were detected using fluorescence-based quantitative reverse transcription-polymerase chain reaction and western blotting. The rates of apoptosis, mitochondrial membrane potentials, reactive oxygen species levels, and cellular calcium levels in the TRPM2-shRNA + OGD group were lower than those observed in the OGD group. Taken together, these results suggest that TRPM2 knockdown reduces OGD-induced neuronal injury, potentially by inhibiting apoptosis and reducing oxidative stress levels, mitochondrial membrane potentials, intracellular calcium concentrations, and NLRP3 inflammasome activation.

The role of a lncRNA (TCONS_00044595) in regulating pineal CLOCK expression after neonatal hypoxia-ischemia brain injury.

A common, yet often neglectable, feature of neonatal hypoxic-ischemic brain damage (HIBD) is circadian rhythm disorders resulted from pineal gland dysfunction. Our previous work demonstrated that miRNAs play an important role in regulating key circadian genes in the pineal gland post HIBD [5,21]. In current study, we sought out to extend our investigation by profiling expression changes of pineal long non-coding RNAs (lncRNAs) upon neonatal HIBD using RNA-Seq. After validating lncRNA changes, we showed that one lncRNA: TCONS_00044595 is highly enriched in the pineal gland and exhibits a circadian expression pattern. Next, we performed bioinformatic analysis to predict the lncRNA-miRNA regulatory network and identified 168 miRNAs that potentially targetlncRNA TCONS_00044595. We further validated the bona fide interaction between one candidate miRNA: miR-182, a known factor to regulate pineal Clock expression, and lncRNA TCONS_00044595. Finally, we showed that suppression of lncRNA TCONS_00044595 alleviated the CLOCK activation both in the cultured pinealocytes under OGD conditions and in the pineal gland post HIBD in vivo. Our study thus shed light into novel mechanisms of pathophysiology of pineal dysfunction post neonatal HIBD.

The role of microglia mediated pyroptosis in neonatal hypoxic-ischemic brain damage.

Neonatal hypoxic-ischemic encephalopathy (HIE) often leads to neonatal death or severe, irreversible neurological deficits. Pathologically, the occurrence of massive cell death and subsequent inflammation suggested that pyroptosis, an inflammation associated programed cell death, might play a role in HIE. Here, by measuring changes of key molecules in pyroptosis pathway in HIE patients, we discovered that their elevation levels tightly correlate with the severity of HIE. Next, we demonstrated that application of MCC950, a small molecule to inhibit NLRP3 inflammasome and thus pyroptosis, substantially alleviated pyroptosis and the injury severity in rats with neonatal hypoxic-ischemic brain damage (HIBD). Mechanistically, we showed that NLRP-3/caspase-1/GSDMD axis is required for microglia pyroptosis and activation. Our data demonstrated that microglia mediated pyroptosis played a crucial role in neonatal HIE, which shed lights into the development of intervention avenues targeting pyroptosis to treat HIE and traumatic brain injuries.

A meta-analysis of dietary carbohydrate intake and inflammatory bowel disease risk: evidence from 15 epidemiology studies

Background and purpose: epidemiological studies that assess the association of dietary total carbohydrate intake and inflammatory bowel disease risk (IBD) have yielded controversial results. Therefore, this study of various epidemiological studies was conducted in order to explore this relationship. Methods: a systematic literature search of the PubMed, Embase, Web of Science and Medline databases was performed up to September 2017. Cohort, case-control or cross-sectional design studies were included that reported the association of dietary carbohydrate intake and IBD risk. Summary odds ratio (OR) and the corresponding 95% CI were calculated using the random effects model. Results: a total of eight articles with 15 individual studies that included 1,361 cases were eligible according to the inclusion criteria. Dietary carbohydrate intake had a non-significant relationship with the risk of IBD (OR = 1.091, 95% CI = 0.817-1.455, I2 = 31.6%, pfor heterogeneity = 0.116). The pooled OR and 95% CI for ulcerative colitis (UC) and Crohn's disease (CD) with regard to dietary carbohydrate intake was 1.167 (0.777-1.752) and 1.010 (0.630-1.618), respectively. These associations were also non-significant in both European and Asia populations. Conclusions: a higher dietary total carbohydrate intake had a non-significant relationship with IBD risk. Further studies with large populations are needed to verify this relationship

No disponible

[Imaging Findings of Pulmonary Cryptococcosis].

Pulmonary cryptococcosis(PC)is a fungal infection that can be easily misdiagnosed due to its non-specific clinical features and imaging findings.This article reviews the imaging findings of PC,their relationships with pathology and immune status,and differential diagnosis of PC with other disease,so as to improve the clinical management of PC.

A meta-analysis of dietary carbohydrate intake and inflammatory bowel disease risk: evidence from 15 epidemiology studies.

BACKGROUND AND PURPOSE: epidemiological studies that assess the association of dietary total carbohydrate intake and inflammatory bowel disease risk (IBD) have yielded controversial results. Therefore, this study of various epidemiological studies was conducted in order to explore this relationship. METHODS: a systematic literature search of the PubMed, Embase, Web of Science and Medline databases was performed up to September 2017. Cohort, case-control or cross-sectional design studies were included that reported the association of dietary carbohydrate intake and IBD risk. Summary odds ratio (OR) and the corresponding 95% CI were calculated using the random effects model. RESULTS: a total of eight articles with 15 individual studies that included 1,361 cases were eligible according to the inclusion criteria. Dietary carbohydrate intake had a non-significant relationship with the risk of IBD (OR = 1.091, 95% CI = 0.817-1.455, I2 = 31.6%, pfor heterogeneity = 0.116). The pooled OR and 95% CI for ulcerative colitis (UC) and Crohn's disease (CD) with regard to dietary carbohydrate intake was 1.167 (0.777-1.752) and 1.010 (0.630-1.618), respectively. These associations were also non-significant in both European and Asia populations. CONCLUSIONS: a higher dietary total carbohydrate intake had a non-significant relationship with IBD risk. Further studies with large populations are needed to verify this relationship.

Nuclear paraspeckle assembly transcript 1 promotes the metastasis and epithelial-mesenchymal transition of hepatoblastoma cells by inhibiting miR-129-5p.

The abnormal expression of nuclear paraspeckle assembly transcript 1 (NEAT1) may serve critical functions for the development and progression of various types of human tumor. However, the expression and biological function of NEAT1 in hepatoblastoma (HB) and the underlying mechanisms for the function of NEAT1 in HB remain largely uncharacterized. In the present study, the results of reverse transcription-quantitative polymerase chain reaction revealed that the expression of NEAT1 was significantly elevated in HB tissues. HB tissues with metastasis also exhibited significantly increased levels of NEAT1 compared with tissues without metastasis. The biological functions of NEAT1 were then assessed using gain-/loss-of-function studies. The results of in vitro assays revealed that inhibiting NEAT1 expression reduced the migration and invasion of HepG2 cells. By contrast, the induced expression of NEAT1 exhibited the opposite effect. The present study also demonstrated that the inhibition of NEAT1 expression prevented the epithelial-mesenchymal transition of HepG2 cells, whereas forced expression of NEAT1 exhibited the opposite effect. In addition, it was confirmed that NEAT1 could modulate the expression of microRNA (miR)-129-5p in HepG2 cells, and that NEAT1 may exert its effect on the metastatic behaviors and epithelial-mesenchymal transition of HepG2 cells by inhibiting miR-129-5p. In conclusion, the present study indicated that NEAT1 expression was aberrantly increased in HB and that it may promote the metastasis of HB cells by inhibiting miR-129-5p. Targeting NEAT1 may potentially be a novel therapeutic option for treating patients with HB.

The direct analysis of drug distribution of rotigotine-loaded microspheres from tissue sections by LESA coupled with tandem mass spectrometry.

The direct analysis of drug distribution of rotigotine-loaded microspheres (RoMS) from tissue sections by liquid extraction surface analysis (LESA) coupled with tandem mass spectrometry (MS/MS) was demonstrated. The RoMS distribution in rat tissues assessed by the ambient LESA-MS/MS approach without extensive or tedious sample pretreatment was compared with that obtained by a conventional liquid chromatography tandem mass spectrometry (LC-MS/MS) method in which organ excision and subsequent solvent extraction were commonly employed before analysis. Results obtained from the two were well correlated for a majority of the organs, such as muscle, liver, stomach, and hippocampus. The distribution of RoMS in the brain, however, was found to be mainly focused in the hippocampus and striatum regions as shown by the LESA-imaged profiles. The LESA approach we developed is sensitive enough, with an estimated LLOQ at 0.05 ng/mL of rotigotine in brain tissue, and information-rich with minimal sample preparation, suitable, and promising in assisting the development of new drug delivery systems for controlled drug release and protection. Graphical abstract Workflow for the LESA-MS/MS imaging of brain tissue section after intramuscular RoMS administration.

Neuroprotective effects of autophagy inhibition on hippocampal glutamate receptor subunits after hypoxia-ischemia-induced brain damage in newborn rats.

Autophagy has been suggested to participate in the pathology of hypoxic-ischemic brain damage (HIBD). However, its regulatory role in HIBD remains unclear and was thus examined here using a rat model. To induce HIBD, the left common carotid artery was ligated in neonatal rats, and the rats were subjected to hypoxia for 2 hours. Some of these rats were intraperitoneally pretreated with the autophagy inhibitor 3-methyladenine (10 mM in 10 µL) or the autophagy stimulator rapamycin (1 g/kg) 1 hour before artery ligation. Our findings demonstrated that hypoxia-ischemia-induced hippocampal injury in neonatal rats was accompanied by increased expression levels of the autophagy-related proteins light chain 3 and Beclin-1 as well as of the AMPA receptor subunit GluR1, but by reduced expression of GluR2. Pretreatment with the autophagy inhibitor 3-methyladenine blocked hypoxia-ischemia-induced hippocampal injury, whereas pretreatment with the autophagy stimulator rapamycin significantly augmented hippocampal injury. Additionally, 3-methyladenine pretreatment blocked the hypoxia-ischemia-induced upregulation of GluR1 and downregulation of GluR2 in the hippocampus. By contrast, rapamycin further elevated hippocampal GluR1 levels and exacerbated decreased GluR2 expression levels in neonates with HIBD. Our results indicate that autophagy inhibition favors the prevention of HIBD in neonatal rats, at least in part, through normalizing GluR1 and GluR2 expression.

Autophagy-regulated AMPAR subunit upregulation in in vitro oxygen glucose deprivation/reoxygenation-induced hippocampal injury.

Autophagy has been implicated to mediate experimental cerebral ischemia/reperfusion-induced neuronal death; the underlying molecular mechanisms, though, are poorly understood. In this study, we investigated the role of autophagy in regulating the expression of AMPAR subunits (GluR1, GluR2, and GluR3) in oxygen glucose deprivation/reperfusion (OGD/R)-mediated injury of hippocampal neurons. Our results showed that, OGD/R-induced hippocampal neuron injury was accompanied by accumulation of autophagosomes and autolysosomes in cytoplasm alongside a dramatic increase in expression of autophagy-related genes, LC3 and Beclin 1 and increased intracellular Ca2+ levels. Pre-treatment with autophagy inhibitor 3-methyladenine (3-MA) significantly reduced this effect. Moreover, the OGD/R-induced upregulation of mRNA and protein expressions of GluR1, GluR2, and GluR3 were also effectively reversed in cells pretreated with 3-MA. Our findings indicate that OGD/R induced the expression of GluRs by activating autophagy in in vitro cultured hippocampal neurons, which could be effectively reversed by the administration of 3-MA.

Melatonin alleviates brain and peripheral tissue edema in a neonatal rat model of hypoxic-ischemic brain damage: the involvement of edema related proteins.

BACKGROUND: Previous studies have indicated edema may be involved in the pathophysiology following hypoxic-ischemic encephalopathy (HIE), and melatonin may exhibit neuro-protection against brain insults. However, little is known regarding the mechanisms that involve the protective effects of melatonin in the brain and peripheral tissues after HIE. The present study aimed to examine the effects of melatonin on multiple organs, and the expression of edema related proteins in a neonatal rat model of hypoxic-ischemic brain damage (HIBD). METHODS: One hundred ninety-two neonatal rats were randomly divided into three subgroups that underwent a sham surgery or HIBD. After the HIBD or sham-injury, the rats received an intraperitoneal injection of melatonin or an equal volume vehicle, respectively. We investigated the effects of melatonin on brain, kidney, and colon edema via histological examination and the expression of edema related proteins, including AQP-4, ZO-1 and occludin, via qPCR and western blot. RESULTS: Our data indicated (1) Melatonin reduced the histological injury in the brain and peripheral organs induced by HIBD as assessed via H-E staining and transmission electron microscopy. (2) Melatonin alleviated the HIBD-induced cerebral edema characterized by increased brain water content. (3) HIBD induced significant changes of edema related proteins, such as AQP-4, ZO-1 and occludin, and these changes were partially reversed by melatonin treatment. CONCLUSIONS: These findings provide substantial evidence that melatonin treatment has protective effects on the brain and peripheral organs after HIBD, and the edema related proteins, AQP4, ZO-1, and occludin, may indirectly contribute tothe mechanism of the edema protection by melatonin.