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1.
Early Hum Dev ; 193: 106036, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38733833

RESUMEN

BACKGROUND: Inter-alpha inhibitor proteins (IAIPs) are structurally related proteins found in the systemic circulation with immunomodulatory anti-inflammatory properties. Reduced levels are found in inflammatory related conditions including sepsis and necrotizing enterocolitis, and in neonatal rodents after exposure to hypoxia ischemia. In the current study, cord blood IAIP levels were measured in neonates with and without exposure to hypoxic-ischemic encephalopathy (HIE). METHODS: This is a prospective cohort study including infants born ≥36 weeks over a one-year period. Term pregnancies were divided into two groups: a "reference control" (uncomplicated term deliveries), and "moderate to severe HIE" (qualifying for therapeutic hypothermia). IAIPs were quantified using a sensitive ELISA on the cord blood samples. RESULTS: The study included 57 newborns: Reference control group (n = 13) and moderate/severe HIE group (n = 44). Measurement of IAIP cord blood concentrations in moderate to severe HIE group [278.2 (138.0, 366.0) µg/ml] revealed significantly lower IAIP concentrations compared with the control group [418.6 (384.5, 445.0) µg/ml] (p = 0.002). CONCLUSIONS: These findings suggest a potential role for IAIPs as indicators of neonates at risk for HIE. IAIP levels could have diagnostic implications in the management of HIE. Future research is required to explore the relationship between HIE and IAIPs as biomarkers for disease severity. CATEGORY OF STUDY: Translational.


Asunto(s)
alfa-Globulinas , Sangre Fetal , Hipoxia-Isquemia Encefálica , Humanos , Recién Nacido , Sangre Fetal/química , Sangre Fetal/metabolismo , Femenino , Hipoxia-Isquemia Encefálica/sangre , Masculino , Estudios de Casos y Controles , Estudios Prospectivos , Biomarcadores/sangre
2.
Neurotherapeutics ; 21(3): e00341, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38453562

RESUMEN

Therapeutic hypothermia is the standard of care for hypoxic-ischemic (HI) encephalopathy. Inter-alpha Inhibitor Proteins (IAIPs) attenuate brain injury after HI in neonatal rats. Human (h) IAIPs (60 â€‹mg/kg) or placebo (PL) were given 15 â€‹min, 24 and 48 â€‹h to postnatal (P) day-7 rats after carotid ligation and 8% oxygen for 90 â€‹min with (30 â€‹°C) and without (36 â€‹°C) exposure to hypothermia 1.5 â€‹h after HI for 3 â€‹h. Hemispheric volume atrophy (P14) and neurobehavioral tests including righting reflex (P8-P10), small open field (P13-P14), and negative geotaxis (P14) were determined. Hemispheric volume atrophy in males was reduced (P â€‹< â€‹0.05) by 41.9% in the normothermic-IAIP and 28.1% in the hypothermic-IAIP compared with the normothermic-PL group, and in females reduced (P â€‹< â€‹0.05) by 30.3% in the normothermic-IAIP, 45.7% in hypothermic-PL, and 55.2% in hypothermic-IAIP compared with the normothermic-PL group after HI. Hypothermia improved (P â€‹< â€‹0.05) the neuroprotective effects of hIAIPs in females. The neuroprotective efficacy of hIAIPs was comparable to hypothermia in female rats (P â€‹= â€‹0.183). Treatment with hIAIPs, hypothermia, and hIAIPs with hypothermia decreased (P â€‹< â€‹0.05) the latency to enter the peripheral zone in the small open field test in males. We conclude that hIAIPs provide neuroprotection from HI brain injury that is comparable to the protection by hypothermia, hypothermia increases the effects of hIAIPs in females, and hIAIPs and hypothermia exhibit some sex-related differential effects.


Asunto(s)
alfa-Globulinas , Animales Recién Nacidos , Hipotermia Inducida , Hipoxia-Isquemia Encefálica , Fármacos Neuroprotectores , Ratas Sprague-Dawley , Animales , Hipoxia-Isquemia Encefálica/terapia , Hipoxia-Isquemia Encefálica/metabolismo , Hipotermia Inducida/métodos , Masculino , Ratas , Femenino , alfa-Globulinas/metabolismo , Humanos
3.
Exp Neurol ; 370: 114563, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37806514

RESUMEN

There is a paucity of information regarding efficacious pharmacological neuroprotective strategies to attenuate or reduce brain injury in neonates. Lipopolysaccharide (LPS) disrupts blood-brain barrier (BBB) function in adult rodents and increases inflammation in adults and neonates. Human blood-derived Inter-alpha Inhibitor Proteins (IAIPs) are neuroprotective, improve neonatal survival after LPS, and attenuate LPS-induced disruption of the BBB in adult male mice. We hypothesized that LPS also disrupts the function of the BBB in neonatal mice and that IAIPs attenuate the LPS-induced BBB disruption in male and female neonatal mice. IAIPs were administered to neonatal mice after LPS and BBB permeability quantified with intravenous 14C-sucrose and 99mTc-albumin. Although repeated high doses (3 mg/kg) of LPS in neonates resulted in high mortality rates and a robust increase in BBB permeability, repeated lower doses (1 mg/kg) of LPS resulted in lower mortality rates and disruption of the BBB in both male and female neonates. IAIP treatment attenuated disruption of the BBB similarly to sucrose and albumin after exposure to low-dose LPS in neonatal mice. Exposure to low-dose LPS elevated IAIP concentrations in blood, but it did not appear to increase the systemic levels of Pre-alpha inhibitor (PaI), one of the family members of the IAIPs that contains heavy chain 3. We conclude that IAIPs attenuate LPS-related disruption of the BBB in both male and female neonatal mice.


Asunto(s)
Barrera Hematoencefálica , Lipopolisacáridos , Ratones , Animales , Masculino , Femenino , Humanos , Barrera Hematoencefálica/metabolismo , Lipopolisacáridos/toxicidad , Animales Recién Nacidos , Albúminas/metabolismo , Sacarosa/metabolismo
4.
FASEB J ; 35(3): e21399, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33559227

RESUMEN

The high-mobility group box-1 (HMGB1) protein is a transcription-regulating protein located in the nucleus. However, it serves as a damage-associated molecular pattern protein that activates immune cells and stimulates inflammatory cytokines to accentuate neuroinflammation after release from damaged cells. In contrast, Inter-alpha Inhibitor Proteins (IAIPs) are proteins with immunomodulatory effects including inhibition of pro-inflammatory cytokines. We have demonstrated that IAIPs exhibit neuroprotective properties in neonatal rats exposed to hypoxic-ischemic (HI) brain injury. In addition, previous studies have suggested that the light chain of IAIPs, bikunin, may exert its anti-inflammatory effects by inhibiting HMGB1 in a variety of different injury models in adult subjects. The objectives of the current study were to confirm whether HMGB1 is a target of IAIPs by investigating the potential binding characteristics of HMGB1 and IAIPs in vitro, and co-localization in vivo in cerebral cortices after exposure to HI injury. Solid-phase binding assays and surface plasmon resonance (SPR) were used to determine the physical binding characteristics between IAIPs and HMGB1. Cellular localizations of IAIPs-HMGB1 in neonatal rat cortex were visualized by double labeling with anti-IAIPs and anti-HMGB1 antibodies. Solid-phase binding and SPR demonstrated specific binding between IAIPs and HMGB1 in vitro. Cortical cytoplasmic and nuclear co-localization of IAIPs and HMGB1 were detected by immunofluorescent staining in control and rats immediately and 3 hours after HI. In conclusion, HMGB1 and IAIPs exhibit direct binding in vitro and co-localization in vivo in neonatal rats exposed to HI brain injury suggesting HMGB1 could be a target of IAIPs.


Asunto(s)
alfa-Globulinas/química , Corteza Cerebral/química , Proteína HMGB1/química , Hipoxia-Isquemia Encefálica/metabolismo , alfa-Globulinas/análisis , Animales , Animales Recién Nacidos , Femenino , Técnica del Anticuerpo Fluorescente , Proteína HMGB1/análisis , Inmunohistoquímica , Ratas , Ratas Wistar , Resonancia por Plasmón de Superficie
5.
Geneva Risk Insur Rev ; 45(2): 134-170, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32952463

RESUMEN

Private insurance coverage for economic losses caused by pandemics is limited. While many factors contribute to reduced demand and supply, we attribute the low amount of coverage to the high levels of capital that would be required to credibly insure pandemic economic losses with cross-sectional pooling mechanisms. Pooling over time significantly reduces the required capital and therefore the cost of insurance, but as a practical matter likely requires a government with the ability to borrow and tax. We also argue that insurance for economic losses due to pandemics likely generates positive externalities for the macroeconomy. We therefore analyze the general tradeoffs associated with different ways that a government can promote such insurance.

6.
Curr Pharm Des ; 26(32): 3997-4006, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32316887

RESUMEN

BACKGROUND: Hypoxic-ischemic (HI) brain injury is a leading cause of long-term neurodevelopmental morbidities in neonates. Human plasma-derived Inter-Alpha Inhibitor Proteins (hIAIPs) are neuroprotective after HI brain injury in neonatal rats. The light chain (bikunin) of hIAIPs inhibits proteases involved in the coagulation of blood. Newborns exposed to HI can be at risk for significant bleeding in the brain and other organs. OBJECTIVE: The objectives of the present study were to assess the pharmacokinetics (PK) and the duration of bleeding after intraperitoneal (IP) administration of hIAIPs in HI-exposed male and female neonatal rats. METHODS: HI was induced with the Rice-Vannucci method in postnatal (P) day-7 rats. After the right common carotid artery ligation, rats were exposed to 90 min of 8% oxygen. hIAIPs (30 mg/kg, IP) were given immediately after Sham or HI exposure in the PK study and serum was collected 1, 6, 12, 24, or 36 h after the injections. Serum hIAIP concentrations were measured with a competitive ELISA. ADAPT5 software was used to fit the pooled PK data considering first-order absorption and disposition. hIAIPs (60 mg/kg, IP) were given in the bleeding time studies at 0, 24 and 48 h after HI with tail bleeding times measured 72 h after HI. RESULTS: IP administration yielded significant systemic exposure to hIAIPs with PK being affected markedly including primarily faster absorption and reduced elimination as a result of HI and modestly of sex-related differences. hIAIP administration did not affect bleeding times after HI. CONCLUSION: These results will help to inform hIAIP dosing regimen schedules in studies of neuroprotection in neonates exposed to HI.


Asunto(s)
Lesiones Encefálicas , Hipoxia-Isquemia Encefálica , Animales , Animales Recién Nacidos , Encéfalo , Femenino , Hemostasis , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Ratas
7.
Risk Manag Insur Rev ; 23(4): 293-304, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34790023

RESUMEN

COVID-19 has proven that pandemic risk deems to the type of catastrophe risk that needs to be treated seriously, by both society and the insurance industry. A key element to measure, manage, and transfer pandemic risk is the modeling capability. This paper first reviews the insured loss from COVID-19 and the impact on the insurance industry. Then, current pandemic risk modeling capabilities and how insurance industry uses these models are evaluated. Some suggestions are made in terms of how these models can be improved in the future and how they can assist in insuring the pandemic risk. Finally, the nonmodeling elements of pandemic risk transfer and the government's role are discussed.

8.
J Cereb Blood Flow Metab ; 40(5): 1090-1102, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31234704

RESUMEN

Circulating levels of inter-alpha inhibitor proteins change dramatically in acute inflammatory disorders, which suggest an important contribution to the immunomodulatory system. Human blood-derived inter-alpha inhibitor proteins are neuroprotective and improve survival of neonatal mice exposed to lipopolysaccharide. Lipopolysaccharide augments inflammatory conditions and disrupts the blood-brain barrier. There is a paucity of therapeutic strategies to treat blood-brain barrier dysfunction, and the neuroprotective effects of human blood-derived inter-alpha inhibitor proteins are not fully understood. To examine the therapeutic potential of inter-alpha inhibitor proteins, we administered human blood-derived inter-alpha inhibitor proteins to male and female CD-1 mice after lipopolysaccharide exposure and quantified blood-brain barrier permeability of intravenously injected 14C-sucrose and 99mTc-albumin. We hypothesized that human blood-derived inter-alpha inhibitor protein treatment would attenuate lipopolysaccharide-induced blood-brain barrier disruption and associated inflammation. Lipopolysaccharide increased blood-brain barrier permeability to both 14C-sucrose and 99mTc-albumin, but human blood-derived inter-alpha inhibitor protein treatment only attenuated increases in 14C-sucrose blood-brain barrier permeability in male mice. Lipopolysaccharide stimulated a more robust elevation of male serum inter-alpha inhibitor protein concentration compared to the elevation measured in female serum. Lipopolysaccharide administration also increased multiple inflammatory factors in serum and brain tissue, including interleukin 6. Human blood-derived inter-alpha inhibitor protein treatment downregulated serum interleukin 6 levels, which were inversely correlated with serum inter-alpha inhibitor protein concentration. We conclude that inter-alpha inhibitor proteins may be neuroprotective through mechanisms of blood-brain barrier disruption associated with systemic inflammation.


Asunto(s)
alfa-Globulinas/farmacología , Barrera Hematoencefálica/efectos de los fármacos , Permeabilidad Capilar/efectos de los fármacos , Interleucina-6/metabolismo , Animales , Regulación hacia Abajo , Femenino , Humanos , Inflamación/inducido químicamente , Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Masculino , Ratones , Fármacos Neuroprotectores/farmacología
9.
Exp Neurol ; 317: 244-259, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30914159

RESUMEN

Hypoxic-ischemic (HI) brain injury is one of the most common neurological problems occurring in the perinatal period. Hypothermia is the only approved intervention for neonatal HI encephalopathy. However, this treatment is only partially protective, has a narrow therapeutic time window after birth and only can be used to treat full-term infants. Consequently, additional therapies are critically needed. Inflammation is an important contributing factor to the evolution of HI brain injury in neonates. Inter-alpha Inhibitor Proteins (IAIPs) are immunomodulatory proteins with anti-inflammatory properties. We have previously shown that IAIPs reduce neuronal cell death and improve behavioral outcomes when given after carotid artery ligation, but before hypoxia in male neonatal rats. The objective of the current study was to investigate the neuroprotective effects of treatment with IAIPs given immediately or 6 h after HI in both male and female neonatal rats. HI was induced with the Rice-Vannucci method in postnatal (P) day 7 rats. After ligation of the right common carotid artery, P7 rats were exposed to 90 min of hypoxia (8% oxygen). Human plasma-derived IAIPs or placebo (phosphate buffered saline) was given at zero, 24, and 48 h after HI. Brains were perfused, weighed and fixed 72 h after HI at P10. In a second, delayed treatment group, the same procedure was followed except that IAIPs or placebo were given at 6, 24 and 48 h after HI. Separate sham-operated, placebo-treated groups were exposed to identical protocols but were not exposed to carotid artery ligation and remained in room air. Rat sex was recorded. The effects of IAIPs on HI brain injury were examined using histopathological scoring and immunohistochemical analyses of the brain and by using infarct volume measurements on frozen tissue of the entire brain hemispheres ipsilateral and contralateral to HI injury. IAIPs given immediately after HI improved (P < 0.050) histopathological brain injury across and within the cingulate, caudate/putamen, thalamus, hippocampus and parietal cortex in males, but not in females. In contrast, IAIPs given immediately after HI reduced (P < 0.050) infarct volumes of the hemispheres ipsilateral to HI injury in similarly both the males and females. Treatment with IAIPs also resulted in higher (P < 0.050) brain weights compared with the placebo-treated HI group, reduced (P < 0.050) neuronal and non-neuronal cell death in the cortex and total hemisphere, and also increased the total area of oligodendrocytes determined by CNPase in the ipsilateral hemisphere and corpus callosum (P < 0.050) of male, but not female subjects exposed to HI. Delayed treatment with IAIPs 6 h after HI did not improve histopathological brain injury in males or females, but resulted in higher (P < 0.050) brain weights compared with the placebo-treated HI males. Therefore, treatment with IAIPs immediately after HI improved brain weights and reduced neuropathological brain injury and cell death in male rats, and reduced infarct volume in both male and female neonatal rats. We conclude that IAIPs exert neuroprotective effects after exposure to HI in neonatal rats and may exhibit some sex-related differential effects.


Asunto(s)
alfa-Globulinas/farmacología , Hipoxia-Isquemia Encefálica/patología , Fármacos Neuroprotectores/farmacología , Animales , Animales Recién Nacidos , Encéfalo/efectos de los fármacos , Encéfalo/patología , Femenino , Humanos , Masculino , Ratas , Ratas Wistar
10.
Int J Dev Neurosci ; 65: 54-60, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29079121

RESUMEN

Hypoxic-ischemic (HI) brain injury is frequently associated with premature and/or full-term birth-related complications that reflect widespread damage to cerebral cortical structures. Inflammation has been implicated in the long-term evolution and severity of HI brain injury. Inter-Alpha Inhibitor Proteins (IAIPs) are immune modulator proteins that are reduced in systemic neonatal inflammatory states. We have shown that endogenous IAIPs are present in neurons, astrocytes and microglia and that exogenous treatment with human plasma purified IAIPs decreases neuronal injury and improves behavioral outcomes in neonatal rats with HI brain injury. In addition, we have shown that endogenous IAIPs are reduced in the brain of the ovine fetus shortly after ischemic injury. However, the effect of HI on changes in circulating and endogenous brain IAIPs has not been examined in neonatal rats. In the current study, we examined changes in endogenous IAIPs in the systemic circulation and brain of neonatal rats after exposure to HI brain injury. Postnatal day 7 rats were exposed to right carotid artery ligation and 8% oxygen for 2h. Sera were obtained immediately, 3, 12, 24, and 48h and brains 3 and 24h after HI. IAIPs levels were determined by a competitive enzyme-linked immunosorbent assay (ELISA) in sera and by Western immunoblots in cerebral cortices. Serum IAIPs were decreased 3h after HI and remained lower than in non-ischemic rats up to 7days after HI. IAIP expression increased in the ipsilateral cerebral cortices 24h after HI brain injury and in the hypoxic contralateral cortices. However, 3h after hypoxia alone the 250kDa IAIP moiety was reduced in the contralateral cortices. We speculate that changes in endogenous IAIPs levels in blood and brain represent constituents of endogenous anti-inflammatory neuroprotective mechanism(s) after HI in neonatal rats.


Asunto(s)
alfa-Globulinas/metabolismo , Lesiones Encefálicas/etiología , Corteza Cerebral/metabolismo , Regulación del Desarrollo de la Expresión Génica/fisiología , Hipoxia-Isquemia Encefálica/complicaciones , Factores de Edad , Animales , Animales Recién Nacidos , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Femenino , Lateralidad Funcional , Masculino , Peso Molecular , Ratas , Ratas Wistar , Factores de Tiempo
11.
Org Lett ; 14(1): 350-3, 2012 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-22149048

RESUMEN

The oxidation of alcohols to aldehydes using stoichiometric 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (1) in CH(2)Cl(2) at room temperature is a highly selective process favoring reaction at the carbinol center best able to accommodate a positive charge. The oxidation of aldehydes to carboxylic acids by 1 in wet acetonitrile is also selective; the rate of the process correlates with the concentration of aldehyde hydrate. A convenient and high yield method for oxidation of alcohols directly to carboxylic acids has been developed.

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