Effects of leptin treatment immediately after neonatal seizures on serum clusterin and VEGF levels and brain oxidative stress-related proteins and neurobehavioral phenotypes.

The developing infant brain has a different response mechanism and repair potential for injury than the adult brain. There is an urgent need for new anticonvulsants to effectively control neonatal seizures while minimizing the drug's toxic damage to the developing brain. Leptin protects neuronal plasma membrane integrity, while it has clinical advantages in terms of anticonvulsant properties as well. This study aimed to evaluate the effect of immediate leptin treatment on the serum concentration of clusterin and vascular endothelial growth factor (VEGF), neuronal plasma membrane integrity-related proteins, and the neurobehavioral phenotypes following neonatal seizures. Leptin was injected i.p at a dose of 4 mg/kg 1 hour after daily 30 minutes prolonged seizures for consecutive 10 days. The serum biomarkers (clusterin and VEGF), and brain protein expression of ATF-4/GRP78/autophagy axis were measured by enzyme-linked immunosorbent assay and western blot in the acute phase (24 hours after the last seizures), respectively. Behavioral and histopathological phenotypes and seizure threshold were conducted from P23 to P34, respectively. There were rapid elevation of serum VEGF and clusterin as well as upregulated protein expression of ATF-4, GRP78, Beclin-1, and LC3 in the cerebral cortex and hippocampus following a neonatal seizure, which was restored by immediate treatment with leptin after seizures. In addition, leptin improved seizure-induced impaired neuropsychological, and cognitive functioning. Furthermore, leptin succeeded in ameliorating markers of neuronal excitability, including seizure threshold and hippocampal mossy fiber sprouting. In conclusion, this study verified that immediate treatment with leptin after neonatal seizures restored both rapid elevation of serum clusterin as well as upregulated protein expression of ATF-4/GRP78/autophagy axis in the cerebral cortex and hippocampus, which contributes to the recovery of neurological function.

Th cytokine profile in childhood-onset systemic lupus erythematosus.

BACKGROUND: Childhood-onset systemic lupus erythematosus (cSLE) is a kind of chronic inflammatory disease characterized by a highly abnormal immune system. This study aimed to detect the serum levels of Th (T helper) cytokines (IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-17A, IL-17F, IL-21, IL-22, IFN-γ and TNF-α) in cSLE and healthy controls, and then to elucidate their association with clinical manifestations, disease activity and laboratory parameters. In order to provide clues for early diagnosis and timely intervention treatment of cSLE patients. METHODS: A total of 33 children with cSLE and 30 healthy children were enrolled in this study. Children in the cSLE group were classified into the inactive or active cSLE group according to their SLE disease activity index 2000 (SLEDAI-2 K) score. Th cytokine profiles in the peripheral blood were detected and analysed. RESULTS: Levels of IL-2, IL-10 and IL-21 in the cSLE group were significantly higher than those in the healthy control group (P < 0.05, P < 0.01 and P < 0.01, respectively). Expression of IL-2, IL-10 and IL-21 in the active cSLE group was significantly higher than that in the healthy control group (P < 0.05, P < 0.01 and P < 0.05, respectively), but that of IL-22 expression was markedly lower in the active cSLE group than in the healthy control group (P < 0.001). IL-21 in the inactive SLE group was significantly higher than that in the healthy control group (P < 0.05), and levels of IL-2 and IL-10 in the active cSLE group were significantly higher than those in the inactive cSLE group (P < 0.01 and P < 0.05). In-depth analysis showed that after excluding age, gender and drug interference, the levels of IL-2 (P < 0.05), IL-6 (P < 0.05) and IL-10 (P < 0.05) were still positively correlated with SLEDAI-2 K scores. However, the levels of IL-6 (P < 0.05) and IFN- γ (P < 0.05) were still negatively correlated with CD4+/CD8+, and the concentration of IL-6 (P < 0.05) was still positively correlated with the occurrence of nephritis. CONCLUSION: This study provides a theoretical basis for the discovery of effective methods to regulate imbalance in T lymphocyte subsets in cSLE, which may lead to new approaches for the diagnosis of cSLE.

The physiological mechanism of the tolerance of Eichhornia crassipes (Mart.) Solms to cadmium.

The tolerance of plants to Cd is a scientific and interesting issue for phytoremediation. In the current study, we attempt to reveal the physiological mechanism of the tolerance of Eichhornia crassipes to cadmium (Cd) by using hydroponic experiments. The results showed that the Cd absorption of E. crassipes was dose-dependent and the absorbed Cd was mainly maintained in the root. The fresh weight was greatly affected by Cd in the early stage of aquatic cultivation. The negative effect of Cd on E. crassipes is dose-dependent, but E. crassipes might adapt to moderate Cd pollution over time. The Cd stimulated the opening of the stomata, and the cell tightness ratio of E. crassipes increased with rising Cd concentrations. The administration of moderate levels of Cd stimulated the release of soluble protein, free proline, malondialdehyde, and soluble polysaccharide. Cd administration also stimulated the activity of superoxide dismutase, peroxidase (POD), catalase, and ascorbic acid peroxidase of E. crassipes, except for POD activity at the highest Cd concentration. This indicates that the physiological mechanism of the tolerance of E. crassipes to Cd depends on osmotic regulation, reduction of lipid peroxidation, improvement of antioxidant properties, increasing palisade tissue while decreasing sponge tissue, and increasing stomatal conductance.

Phosphate-solubilizing bacteria improve the phytoremediation efficiency of Wedelia trilobata for Cu-contaminated soil.

In a controlled experiment, we assessed the effect of phosphate-solubilizing bacterium (PSB) on the soil metal (Cu2+) phytoremediation by Wedelia trilobata and examined the effect of the interaction of Cu contamination and PSB on the growth of W. trilobata. We also explored the effect of the interaction of Cu contamination and PSB on the soil microflora. The results showed that the removal efficiency of Cu from soil by W. trilobata increased with an increase in the concentration of PSB, and the translocation factors of Cu (i.e., leaf:root and stem:root) were both significantly upregulated by PSB. The PSB significantly promoted the growth of W. trilobata; however, the effect of the Cu-PSB interaction on the leaf net photosynthetic rate (Pn) of W. trilobata was not significant, whereas copper contamination had a significant negative influence on the soil microflora, PSB had a significant positive influence on the soil microflora. Thus, PSB improved the phytoremediation efficiency of W. trilobata in Cu-contaminated soil because of the positive influence on the soil microflora, improving soil quality, which then increased the growth of W. trilobata in Cu-contaminated soil. The vigorous growth of W. trlobata led to higher of Cu absorption and translocation from soil as the ultimate result.

[Establishment and validation of a neonatal pig model of hemolytic jaundice].

OBJECTIVE: To establish a neonatal pig model of hemolytic jaundice. METHODS: Twelve seven-day-old purebred Yorkshire pigs were randomly divided into an experimental group and a control group (n=6 each). Immunization of New Zealand white rabbits was used to prepare rabbit anti-porcine red blood cell antibodies, and rabbit anti-porcine red blood cell serum was separated. The neonatal pigs in the experimental group were given an intravenous injection of rabbit anti-porcine red blood cell serum (5 mL), and those in the control group were given an intravenous injection of normal saline (5 mL). Venous blood samples were collected every 6 hours for routine blood test and liver function evaluation. RESULTS: The experimental group had a significantly higher serum bilirubin level than the control group at 18 hours after the injection of rabbit anti-porcine red blood cell serum (64±30 µmol/L vs 20±4 µmol/L; P<0.05). In the experimental group, the serum bilirubin level reached the peak at 48 hours (275±31 µmol/L), and decreased significantly at 96 hours after the injection (95±17 µmol/L), but all significantly higher than that in the control group (P<0.05). At 18 hours after the injection, the experimental group had a significantly lower red blood cell (RBC) count than the control group [(4.58±0.32)×10(12)/L vs (5.09±0.44)×10(12)/L; P<0.05]; at 24 hours, the experimental group showed further reductions in RBC count and hemoglobin level and had significantly lower RBC count and hemoglobin level than the control group [RBC: (4.21±0.24)×10(12)/L vs (5.11±0.39)×10(12)/L, P<0.05; hemoglobin: 87±3 g vs 97±6 g, P<0.05]. The differences in RBC count and hemoglobin level between the two groups were largest at 36-48 hours. CONCLUSIONS: The neonatal pig model of hemolytic jaundice simulates the pathological process of human hemolytic jaundice well and provides good biological and material bases for further investigation of neonatal hemolysis.

Molecular targeting of the oncoprotein PLK1 in pediatric acute myeloid leukemia: RO3280, a novel PLK1 inhibitor, induces apoptosis in leukemia cells.

Polo-like kinase 1 (PLK1) is highly expressed in many cancers and therefore a biomarker of transformation and potential target for the development of cancer-specific small molecule drugs. RO3280 was recently identified as a novel PLK1 inhibitor; however its therapeutic effects in leukemia treatment are still unknown. We found that the PLK1 protein was highly expressed in leukemia cell lines as well as 73.3% (11/15) of pediatric acute myeloid leukemia (AML) samples. PLK1 mRNA expression was significantly higher in AML samples compared with control samples (82.95 ± 110.28 vs. 6.36 ± 6.35; p < 0.001). Kaplan-Meier survival analysis revealed that shorter survival time correlated with high tumor PLK1 expression (p = 0.002). The 50% inhibitory concentration (IC50) of RO3280 for acute leukemia cells was between 74 and 797 nM. The IC50 of RO3280 in primary acute lymphocytic leukemia (ALL) and AML cells was between 35.49 and 110.76 nM and 52.80 and 147.50 nM, respectively. RO3280 induced apoptosis and cell cycle disorder in leukemia cells. RO3280 treatment regulated several apoptosis-associated genes. The regulation of DCC, CDKN1A, BTK, and SOCS2 was verified by western blot. These results provide insights into the potential use of RO3280 for AML therapy; however, the underlying mechanisms remain to be determined.

Ovalbumin-induced experimental allergic asthma is Toll-like receptor 2 dependent.

The role of Toll-like receptor (TLR) 2 in modulating allergy-induced asthma is contradictory. We investigated the effect of TLR2 gene deletion in a murine model of ovalbumin (OVA)-challenged asthma. TLR2 wild-type (TLR2(+/+)) and TLR2-deficient (TLR2(-/-)) mice were sensitized to soluble OVA antigens and challenged with OVA, and the extent of allergic airways disease was analyzed in both groups of mice at day 8 after being challenged with OVA aerosol. At day 8 post-OVA, TLR2(-/-) mice exhibited significantly lower airway hyperresponsiveness, airway inflammation, and whole lung T-helper type 2 (Th2) cytokine levels compared with the TLR2(+/+) group. TLR2 deletion also significantly reduced mucus cell metaplasia and peribronchial fibrosis in mice at day 8 after challenged by OVA. The p38/AKT/nuclear factor kappaB (NF-kappaB) p65 and phosphate extracellular signal-regulated kinase (ERK)/p38/AKT was decreased in TLR2(-/-) mouse lungs. Thus, during OVA asthma in mice, TLR2 is a major contributor to the maintenance of the adaptive Th2-cytokine-driven inflammatory disorder and ERK/p38 as well as AKT/NF-κB playing a role in it.

[Diagnostic values of neopterin and S100b for central nervous system infections in children].

OBJECTIVE: To study the diagnostic values of cerebrospinal concentrations of neopterin (NPT) and S100b for central nervous system infections in children. METHODS: Enzyme-linked immunosorbent assay was used to determinate the cerebrospinal concentrations of NPT and S100b in children with central nervous system infections and control children. The two groups of children were compared in terms of the two indicators, and the diagnostic values of the two indicators were evaluated by ROC curve analysis. RESULTS: Children with viral encephalitis had significantly increased cerebrospinal concentrations of NPT and S100b compared with the control group and children with purulent meningitis (P<0.01); there was no difference in the cerebrospinal concentration of NPT between children with purulent meningitis and the control group, while the concentration of S100b in the purulent meningitis group was significantly higher than in the control group (P<0.01). According to the ROC curves, S100b was more valuable than NPT in the diagnosis of viral encephalitis; when cerebrospinal concentration was more than 0.384 ng/mL, S100b had a sensitivity of 93.3% and a specificity of 97.9%; a combination of the two indicators had a higher diagnostic value for viral encephalitis, with a sensitivity of 96.7% and a specificity of 97.9%. CONCLUSIONS: Both NPT and S100b have certain values in the diagnosis of central nervous system infections in children, and S100b is better than NPT.

[Impact of neonatal exposure to different doses of bisphenol A on puberty in female rats].

OBJECTIVE: To evaluate the effects of neonatal exposure to different doses of bisphenol A (BPA) on the vaginal opening day (VOD), hypothalamic Kiss-1 mRNA expression, and ovarian estrogen receptor (ER) mRNA expression in female rats. METHODS: Neonatal female Sprague-Dawley (SD) rats were randomly divided into six groups: blank control, vehicle, 17ß-estradiol (17ß-estradiol, E2, 10 µg/d), low-dose BPA [25 µg(kg·d)], medium-dose BPA [50 µg(kg·d)], and high-dose BPA groups [250 µg(kg·d)]. The rats were subcutaneously injected with respective agents on postnatal days 0-6. The VOD was recorded, and each rat was sacrificed on the same day. The hypothalamus and ovary were taken and weighed, and the organ coefficients of hypothalamus and ovary were calculated. The hypothalamic Kiss-1 mRNA expression and ovarian ERα and ERß mRNA expression were measured by real-time PCR. RESULTS: Compared with the control group, the E2 and medium- and high-dose BPA groups had advanced VOD, and the E2 group had significantly reduced hypothalamic Kiss-1 mRNA expression and ovarian ERß mRNA expression (P<0.05). CONCLUSIONS: Neonatal exposure to medium- and high-dose BPA[50 and 250 µg/(kg·d)] can induce precocious puberty in rats, but it may not result from the change in hypothalamic Kiss-1 mRNA expression. Neonatal exposure to low-dose BPA [25 µg/(kg·d)] does not induce precocious puberty in rats.

Nicotinamide adenine dinucleotide treatment confers resistance to neonatal ischemia and hypoxia: effects on neurobehavioral phenotypes.

JOURNAL/nrgr/04.03/01300535-202412000-00031/figure1/v/2024-04-08T165401Z/r/image-tiff Neonatal hypoxic-ischemic brain injury is the main cause of hypoxic-ischemic encephalopathy and cerebral palsy. Currently, there are few effective clinical treatments for neonatal hypoxic-ischemic brain injury. Here, we investigated the neuroprotective and molecular mechanisms of exogenous nicotinamide adenine dinucleotide, which can protect against hypoxic injury in adulthood, in a mouse model of neonatal hypoxic-ischemic brain injury. In this study, nicotinamide adenine dinucleotide (5 mg/kg) was intraperitoneally administered 30 minutes before surgery and every 24 hours thereafter. The results showed that nicotinamide adenine dinucleotide treatment improved body weight, brain structure, adenosine triphosphate levels, oxidative damage, neurobehavioral test outcomes, and seizure threshold in experimental mice. Tandem mass tag proteomics revealed that numerous proteins were altered after nicotinamide adenine dinucleotide treatment in hypoxic-ischemic brain injury mice. Parallel reaction monitoring and western blotting confirmed changes in the expression levels of proteins including serine (or cysteine) peptidase inhibitor, clade A, member 3N, fibronectin 1, 5'-nucleotidase, cytosolic IA, microtubule associated protein 2, and complexin 2. Proteomics analyses showed that nicotinamide adenine dinucleotide ameliorated hypoxic-ischemic injury through inflammation-related signaling pathways (e.g., nuclear factor-kappa B, mitogen-activated protein kinase, and phosphatidylinositol 3 kinase/protein kinase B). These findings suggest that nicotinamide adenine dinucleotide treatment can improve neurobehavioral phenotypes in hypoxic-ischemic brain injury mice through inflammation-related pathways.

Erratum: [Corrigendum] Relationship between changes in mitochondrial function and hippocampal neuronal apoptosis after recurrent convulsion during developmental stage.

[This corrects the article DOI: 10.3892/etm.2018.6147.].

Impact of sepsis on the urinary level of interleukin-18 and cystatin C in critically ill neonates.

BACKGROUND: Urinary interleukin-18 (uIL-18) and cystatin C (uCysC) are biomarkers of acute kidney injury (AKI). We hypothesized that in non-AKI neonates, the level of uIL-18 and uCysC would be higher in those with sepsis compared to those without sepsis. The aims of this study were to determine the association between urinary biomarkers and sepsis in non-AKI critically ill neonates, and to evaluate whether uIL-18 and uCysC could serve as predictors of sepsis in this population. METHODS: The study included 111 non-AKI critically ill neonates with acute clinical deterioration suggestive of sepsis: 26 with infection, 57 without infection, and 28 were assigned to the unclassified group. Urinary samples were collected and a full sepsis screen was performed at the time of enrollment. RESULTS: The level of uIL-18, but not uCysC, was significantly elevated in non-AKI septic neonates. Urinary IL-18 was an independent factor associated with sepsis assessed by multivariate analysis, had odds ratio of 1.73 (95 % CI 1.15 to 2.58, p = 0.008), and achieved the area under the receiver operating characteristic curve of 0.74 for predicting the presence of sepsis in non-AKI critically ill neonates. CONCLUSIONS: Sepsis has an impact on the level of uIL-18, but not on the uCysC in non-AKI neonates, suggesting systemic infection might influence the diagnostic value of uIL-18 to detect AKI in the general population.

Higher expression of phosphorylated myosin regulatory light chain in the common bile duct in pancreaticobiliary maljunction accompanied by bile duct dilatation in children: a post-mortem observational study.

PURPOSE: To examine the content of phosphorylated myosin regulatory light chain (P-MLC20) and myosin light-chain kinase (MLCK) in the common bile duct of pediatric patients with pancreaticobiliary maljunction (PBM) accompanied by bile duct dilatation (BDD), and investigate their potential role in PBM accompanied by BDD. METHODS: Twenty-one specimens of the common bile duct from pediatric patients with PBM accompanied by BDD were collected. P-MLC20 was examined with immunohistochemistry. The expression of P-MLC20 and MLCK was also examined with Western blot. Twenty-one specimens of the common bile duct from pediatric patients without PBM and BDD were used as controls. RESULTS: The mean optical density (MOD), mean labeling intensity (MLI) and minimum qualifying scores (MQS) of P-MLC20 were 115.6856 ± 58.1634, 21.7125 % ± 9.6555 and 21.3531 ± 6.5255, respectively. In the control group, MOD, MLI and MQS were 96.5581 ± 9.7859, 11.1813 % ± 3.6208 and 10.7819 ± 3.5323, respectively. There was no significant difference in MOD between the two groups (P > 0.05), whereas there was a significant difference in MLI and MQS between the two groups (P < 0.05). The expression of P-MLC20 and MLCK, as determined with Western blot, was also significantly higher in the PBM group than in the control group (P < 0.05). CONCLUSION: P-MLC20 is associated with increased contractile force of the smooth muscle of the common bile duct in pediatric patients with PBM accompanied by BDD. The enhanced expression of P-MLC20 in the common bile duct probably contributes to increased bile duct pressure in PBM via the MLCK pathway.

[Changes of biological clock protein in neonatal rats with hypoxic-ischemic brain damage].

OBJECTIVE: To study the effects of biological clock protein on circadian disorders in hypoxic-ischemic brain damage (HIBD) by examining levels of CLOCK and BMAL1 proteins in the pineal gland of neonatal rats. METHODS: Seventy-two 7-day-old Sprague-Dawley (SD) rats were randomly divided into sham-operated and HIBD groups. HIBD model was prepared according to the modified Levine method. Western blot analysis was used to measure the levels of CLOCK and BMAL1 in the pineal gland at 0, 2, 12, 24, 36 and 48 hours after operation. RESULTS: Both CLOCK and BMAL levels in the pineal gland increased significantly 48 hours after HIBD compared with the sham-operated group (P<0.05). There were no significant differences in levels of CLOCK and BMAL proteins between the two groups at 0, 2, 12, 24 and 36 hours after operation (P>0.05). CONCLUSIONS: Levels of CLOCK and BMAL1 proteins in the pineal gland of rats increase significantly 48 hours after HIBD, suggesting that both CLOCK and BMAL1 may be involved the regulatory mechanism of circadian disorders in rats with HIBD.

Zinc Water Prevents Autism-Like Behaviors in the BTBR Mice.

This study aims to explore the effects of zinc water on autism-like behavior, convulsion threshold, and neurogenesis in ASD model animals. This study used the young BTBR ASD mouse model to explore the effect of a 6-week zinc water supplementation on ASD-like behaviors such as repetitive behavior and social communication disorder, seizure threshold, and the correlation with excitability regulation. The mice were divided into four groups of normal controls (B6) and models (BTBR) who did and did not receive zinc supplementation in water (B6, B6 + zinc, BTBR, and BTBR + zinc). For morphological changes in the hippocampus, we selected two indicators: hippocampal mossy fiber sprouting and neurogenesis. ASD-like behavior testing, seizure threshold determination, Timm staining, and neurogenesis-related assays-represented by Ki67 and DCX-were performed after 6 weeks of zinc supplementation. Our results show that zinc water can prevent autism-like behavior, reduce susceptibility to convulsions, and increase the proliferation of hippocampal progenitor cells in BTBR mice but has less effect on mossy fiber sprouting and neural progenitor cell differentiation. Zinc water reduces autism-like behavior in a partially inherited autism model mice-BTBR-which may be associated with hippocampal neural precursor cell proliferation and reversed hyperexcitability.

Urine interleukin-18 and cystatin-C as biomarkers of acute kidney injury in critically ill neonates.

BACKGROUND: Urinary interleukin-18 and cystatin-C are suggested to be biomarkers for predicting acute kidney injury (AKI). The aims of this study are to examine whether the urinary concentrations of interleukin-18 and cystatin-C vary with gestational age and other factors in non-AKI control neonates, and to determine whether urinary interleukin-18 and cystatin-C can predict AKI development in non-septic critically ill neonates, independently of potential confounders. METHODS: We enrolled 62 non-septic critically ill neonates. Urine was collected every 48-72 h during the first 10 days of life. RESULTS: Urinary concentration of cystatin-C, but not interleukin-18, decreased with increasing gestational age and body weight, but not with increasing postnatal age in non-AKI control neonates. Both urinary interleukin-18 and cystatin-C were associated with AKI, even after controlling for gestational and postnatal age, birth weight, gender, Apgar score and the score for neonatal acute physiology in non-septic critically ill neonates. Urinary interleukin-18 and cystatin-C had odds ratios of 2.27 and 2.07, and achieved the area under-the-receiver-operating-characteristic curve of 0.72 and 0.92, respectively, for predicting AKI. CONCLUSIONS: The urinary concentration of cystatin-C, but not interleukin-18, may decrease with increasing renal maturity. Both urinary interleukin-18 and cystatin-C are independently predictive of AKI in non-septic critically ill neonates.

Poly[(2,2'-bipyridine-κN,N')(µ(3)-2,4,6-trimethyl-isophthalato-κO,O:O:O,O)cadmium].

In the crystal structure of the polymeric title complex, [Cd(C(11)H(10)O(4))(C(10)H(8)N(2))](n), the Cd(II) cation is chelated by one 2,2-bipyridine ligand and two carboxyl groups from two trimethyl-isophthalate (TMIPA) anions, and is further coordinated by one carboxyl-ate O atom from a third TMIPA anion, forming a distorted penta-gonal-bipyramidal geometry. Each TMIPA anion bridges three Cd(II) cations, forming polymeric complex sheets parallel to (001). Weak C-H⋯O hydrogen bonding occurs between adjacent sheets.

Plppr5 gene inactivation causes a more severe neurological phenotype and abnormal mitochondrial homeostasis in a mouse model of juvenile seizure.

Mice with inactivation of the Plppr5 gene (Plppr5-/-) had aggravated hypoxic-ischemic damage and partially weakened neuroprotection of melatonin (a mitochondrial targeted antioxidant), suggesting that abnormal mitochondrial homeostasis contributes to neurological abnormalities in these mice. We examined the hypothesis that Plppr5 inactivation disturbs mitochondrial homeostasis, which may cause long-term adverse consequences on behavior and cognition. We studied the long-term effects of Plppr5 knockout (KO) in both wild-type (WT) and Plppr5-null mice using a combination of neurobehavior, cognition, and standard cellular glutamate-induced excitotoxicity techniques. The change in mitochondrial membrane potential was determined by detecting MitoTracker Green FM and MitoTracker Red CMXROS with a Gallios flow cytometer. Our results suggest that Plppr5 gene knockout aggravated the impairment of exploratory behavior (open field test) and memory (novel object recognition and passive avoidance tests) in Plppr5-null mice following juvenile seizures. Furthermore, Plppr5 gene silencing aggravated the decrease in the cell survival rate of HT22 cells treated with glutamate for 24 h and further resulted in a decrease in superoxide dismutase (SOD) levels and the ratio of active mitochondria and a parallel increase in the reactive oxygen species (ROS) content. Interestingly, silencing the Plppr5 gene alone in vitro is sufficient to reduce the cell survival rate, aggravate oxidative stress damage, reduce the proportion of surviving mitochondria, and upregulate mitophagy activity. In summary, the present data reveal the first direct link between Plppr5 KO and neurobehavioral and cognitive impairment following juvenile seizures and provide a potential mechanistic explanation for the adverse consequences. Given that silencing the Plppr5 gene is sufficient to upregulate mitophagy activity and aggravate oxidative stress neuronal damage, our results suggest that Plppr5 substrates and/or mitophagy-based treatments may provide valuable new targets for the treatment of developmental convulsive brain injury.

Genetic Inhibition of Plppr5 Aggravates Hypoxic-Ischemie-Induced Cortical Damage and Excitotoxic Phenotype.

Hypoxia-ischemia (HI) is the most common acute brain threat in neonates and a leading cause of neurodevelopmental impairment. Exploring the new molecular mechanism of HI brain injury has important clinical translational significance for the next clinical intervention research. Lipid phosphatase-related proteins (PLPPRs) are regulators of mitochondrial membrane integrity and energy metabolism. We recently found that Plppr5 knockout exacerbated HI impairment in some aspects and partially attenuated the neuroprotective effects of melatonin, suggesting that Plppr5 may be a novel intervention target for HI. The present study aimed to determine the long-term effects of gene knockout of Plppr5 on HI brain injury, focusing on the neuronal excitability phenotype, and to determine the effect of Plppr5 gene silencing on neuronal zinc metabolism and mitochondrial function in vitro. 10-day-old wild type (WT) mice and Plppr5-deficient (Plppr5 -/-) mice were subjected to hypoxia-ischemia. Lesion volumes and HI-induced neuroexcitotoxic phenotypes were quantified together with ZnT1 protein expression in hippocampus. In addition, HT22 (mouse hippocampal neuronal cells) cell model was established by oxygen-glucose deprivation/reoxygenation (OGD/R) treatment and was treated with medium containing LV-sh_Plppr5 or control virus. Mitochondrial oxidative stress indicator ROS, mitochondrial ZnT1 protein expression and zinc ion content were detected. Results: Plppr5-deficient mice subjected to hypoxia-ischemia at postnatal day 10 present significantly higher cerebral infarction. Plppr5-deficient mice were endowed with a more pronounced superexcitability phenotype at 4 weeks after HI, manifested as a reduced seizure threshold. ZnT1 protein was also found reduced in Plppr5-deficient mice as well as in mice subjected to HI excitotoxicity. Plppr5 knockout in vivo exacerbates HI brain injury phenotypes, including infarct volume and seizure threshold. In addition, knockout of the Plppr5 gene reduced the MFS score to some extent. In vitro Plppr5 silencing directly interferes with neuronal zinc metabolism homeostasis and exacerbates hypoxia-induced mitochondrial oxidative stress damage. Taken together, our findings demonstrate for the first time that Plppr5-deficient mouse pups exposed to neuronal hypoxia and ischemia exhibit aggravated acute brain injury and long-term brain excitability compared with the same treated WT pups, which may be related to the disruption of zinc and mitochondria-dependent metabolic pathways in the hippocampus. These data support further investigation into novel approaches targeting Plppr5-mediated zinc and mitochondrial homeostasis in neonatal HIE.

Corrigendum: Effects of Melatonin on Neurobehavior and Cognition in a Cerebral Palsy Model of plppr5-/- Mice.

[This corrects the article DOI: 10.3389/fendo.2021.598788.].