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1.
Antimicrob Agents Chemother ; 67(5): e0170722, 2023 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-37010414

RESUMEN

Ceftazidime is an antibiotic commonly used to treat bacterial infections in term neonates undergoing controlled therapeutic hypothermia (TH) for hypoxic-ischemic encephalopathy after perinatal asphyxia. We aimed to describe the population pharmacokinetics (PK) of ceftazidime in asphyxiated neonates during hypothermia, rewarming, and normothermia and propose a population-based rational dosing regimen with optimal PK/pharmacodynamic (PD) target attainment. Data were collected in the PharmaCool prospective observational multicenter study. A population PK model was constructed, and the probability of target attainment (PTA) was assessed during all phases of controlled TH using targets of 100% of the time that the concentration in the blood exceeds the MIC (T>MIC) (for efficacy purposes and 100% T>4×MIC and 100% T>5×MIC to prevent resistance). A total of 35 patients with 338 ceftazidime concentrations were included. An allometrically scaled one-compartment model with postnatal age and body temperature as covariates on clearance was constructed. For a typical patient receiving the current dose of 100 mg/kg of body weight/day in 2 doses and assuming a worst-case MIC of 8 mg/L for Pseudomonas aeruginosa, the PTA was 99.7% for 100% T>MIC during hypothermia (33.7°C; postnatal age [PNA] of 2 days). The PTA decreased to 87.7% for 100% T>MIC during normothermia (36.7°C; PNA of 5 days). Therefore, a dosing regimen of 100 mg/kg/day in 2 doses during hypothermia and rewarming and 150 mg/kg/day in 3 doses during the following normothermic phase is advised. Higher-dosing regimens (150 mg/kg/day in 3 doses during hypothermia and 200 mg/kg/day in 4 doses during normothermia) could be considered when achievements of 100% T>4×MIC and 100% T>5×MIC are desired.


Asunto(s)
Hipotermia Inducida , Hipotermia , Hipoxia-Isquemia Encefálica , Recién Nacido , Humanos , Ceftazidima/farmacología , Hipotermia/tratamiento farmacológico , Antibacterianos/farmacología
2.
J Anesth ; 37(6): 835-840, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37566231

RESUMEN

PURPOSE: Perioperative shivering is common and can occur as a result of hypothermia or changes in the threshold of thermoregulation. Droperidol usage for anesthesia is currently limited to its sedative and antiemetic effects. We investigated the effects of high and low doses of droperidol on the shivering threshold in rabbits. METHODS: Forty-two male Japanese white rabbits were anesthetized with isoflurane and randomly assigned to the control, high-dose, or low-dose group. Rabbits in the high-dose group received a 5 mg/kg droperidol bolus followed by continuous infusion at 5 mg/kg/h, those in the low-dose group received a 0.5 mg/kg droperidol bolus, and those in the control group received the same volume of saline as the high-dose group. Body temperature was reduced at a rate of 2-3 °C/h, and the shivering threshold was defined as the subject's core temperature (°C) at the onset of shivering. RESULTS: The shivering thresholds in the control, high-dose, and low-dose groups were 38.1 °C ± 1.1 °C, 36.7 °C ± 1.2 °C, and 36.9 °C ± 1.0 °C, respectively. The shivering thresholds were significantly lower in the high-dose and low-dose groups than in the control group (P < 0.01). The thresholds were comparable between the high-dose and low-dose groups. CONCLUSIONS: Droperidol in high and low doses effectively reduced the shivering threshold in rabbits. Droperidol has been used in low doses as an antiemetic. Low doses of droperidol can reduce the incidence of shivering perioperatively and during the induction of therapeutic hypothermia.


Asunto(s)
Hipotermia , Isoflurano , Animales , Conejos , Masculino , Tiritona/fisiología , Droperidol/farmacología , Temperatura Corporal/fisiología , Isoflurano/farmacología , Hipotermia/tratamiento farmacológico
3.
J Pineal Res ; 73(2): e12818, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35841265

RESUMEN

Neonatal encephalopathy (NE) is a pathological condition affecting long-term neurodevelopmental outcomes. Hypothermia is the only therapeutic option, but does not always improve outcomes; hence, researchers continue to hunt for pharmaceutical compounds. Melatonin treatment has benefitted neonates with hypoxic-ischemic (HI) brain injury. However, unlike animal models that enable the study of the brain and the pathophysiologic cascade, only blood is available from human subjects. Therefore, due to the unavailability of neonatal brain tissue, assumptions about the pathophysiology in pathways and cascades are made in human subjects with NE. We analyzed animal and human specimens to improve our understanding of the pathophysiology in human neonates. A neonate with NE who underwent hypothermia and enrolled in a melatonin pharmacokinetic study was compared to HI rats treated/untreated with melatonin. MicroRNA (miRNA) analyses provided profiles of the neonate's plasma, rat plasma, and rat brain cortexes. We compared these profiles through a bioinformatics tool, identifying Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways common to HI brain injury and melatonin treatment. After evaluating the resulting pathways and the literature, to validate the method, the key proteins expressed in HI brain injury were investigated using cerebral cortexes. The upregulated miRNAs in human neonate and rat plasma helped identify two KEGG pathways, glioma and long-term potentiation, common to HI injury and melatonin treatment. A unified neonatal cerebral melatonin-sensitive HI pathway was designed and validated by assessing the expression of protein kinase Cα (PKCα), phospho (p)-Akt, and p-ERK proteins in rat brain cortexes. PKCα increased in HI-injured rats and further increased with melatonin. p-Akt and p-ERK returned phosphorylated to their basal level with melatonin treatment after HI injury. The bioinformatics analyses validated by key protein expression identified pathways common to HI brain injury and melatonin treatment. This approach helped complete pathways in neonates with NE by integrating information from animal models of HI brain injury.


Asunto(s)
Lesiones Encefálicas , Hipotermia , Hipoxia-Isquemia Encefálica , Melatonina , MicroARNs , Animales , Animales Recién Nacidos , Humanos , Hipotermia/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/genética , Hipoxia-Isquemia Encefálica/metabolismo , Melatonina/farmacología , Melatonina/uso terapéutico , MicroARNs/genética , Proteína Quinasa C-alfa , Proteínas Proto-Oncogénicas c-akt , Ratas
4.
Cell Mol Biol (Noisy-le-grand) ; 68(4): 36-45, 2022 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-35988285

RESUMEN

After perinatal asphyxia, hypoxic-ischemic encephalopathy (HIE) in term infants produces long-term neurologic sequelae or death. Obtaining a reliable, evidence-based prognosis is critical. Therapeutic hypothermia is a suggested treatment for newborn babies with moderate-to-severe HIE at or near term. However, this treatment is unsuccessful in a significant proportion of newborns. This sparked a worldwide hunt for neuroprotectants that may enhance the effects of mild hypothermia. We look at erythropoietin (EPO) as a possible possibility. This research aimed to see how EPO paired with moderate hypothermia affects oxidative stress and neuroprotection in newborns with HIE. Children with HIE diagnosed and treated at the hospital were first recruited as research participants and split into two groups using a random number system. The control group got mild hypothermia therapy as part of their standard treatment, whereas the EPO group received EPO therapy in addition to mild hypothermia therapy. Statistical analysis techniques such as the Mann-Whitney U test, Chi-squared test, and t-test were used to examine the effects. The data show that the efficacies of combination therapy of mild hypothermia and EPO for infant HIE seem to be promising right now.


Asunto(s)
Eritropoyetina , Hipotermia , Hipoxia-Isquemia Encefálica , Niño , Eritropoyetina/uso terapéutico , Humanos , Hipotermia/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Lactante , Recién Nacido , Neuroprotección , Estrés Oxidativo
5.
J Neurooncol ; 152(3): 467-482, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33740164

RESUMEN

PURPOSE: Glioblastoma is the most common malignant brain tumor, currently treated by surgery followed by concomitant radiotherapy and temozolomide-based chemotherapy. Despite these treatments, median survival is only 15 months as a result of tumor recurrence in the resection margins. Here, we propose therapeutic hypothermia - known to have neuroprotective effects - as an adjuvant treatment to maintain residual glioblastoma cells in a dormant state, and thus prevent tumor recurrence. METHODS: In vitro experiments were performed on healthy tissue with primary human astrocytes, and four human glioblastoma cell lines: A172, U251, U87, and T98G. We explored the adjuvant potential of moderate hypothermia (28 °C) by studying the reversibility of its inhibitory effects on cell proliferation and comparing them to currently used temozolomide. RESULTS: Moderate hypothermia reduced healthy cell growth, but also inhibited glioblastoma cell proliferation even after rewarming. Indeed, hypothermic preconditioning duration strongly enhanced inhibitory effects from 35% after 3 days to 100% after 30 days. In contrast, moderate (28 °C) and severe (23 °C) preconditioning induced similar results. Finally, moderate hypothermia had more uniform inhibitory effects than temozolomide, which reduced proliferation by between 15% and 95%, and also potentiated the effects of the latter. CONCLUSION: Moderate hypothermia shows promise as an adjuvant therapy for glioblastoma through its inhibition of cell proliferation beyond direct conditioning and potentiation of the effects of chemotherapy. If in vivo preclinical results corroborate our findings, therapeutic hypothermia applied at the resection margins could probably inhibit tumor growth, delay tumor recurrence and reduce inter-patient variability.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Hipotermia Inducida , Hipotermia , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Quimioterapia Adyuvante , Glioblastoma/tratamiento farmacológico , Humanos , Hipotermia/tratamiento farmacológico , Márgenes de Escisión , Recurrencia Local de Neoplasia/tratamiento farmacológico , Temozolomida/uso terapéutico
6.
Chem Pharm Bull (Tokyo) ; 69(4): 314-324, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33790077

RESUMEN

We explored orally effective thyrotropin-releasing hormone (TRH) mimetics, which show high central nervous system effects in structure-activity relationship studies based on in vivo antagonistic activity on reserpine-induced hypothermia (anti-hypothermic effect) in mice starting from TRH. This led us to the TRH mimetic: [(4S,5S)-(5-methyl-2-oxooxazolidine-4-yl)carbonyl]-[3-(thiazol-4-yl)-L-alanyl]-L-prolinamide 1, which shows a higher anti-hypothermic effect compared with that of TRH after oral administration. We next attempted further chemical modification of the N- and C-terminus of 1 to find more orally effective TRH mimetics. As a result, we obtained several N- and C-terminus modified TRH mimetics which showed high anti-hypothermic effects.


Asunto(s)
Hipotermia/tratamiento farmacológico , Prolina/análogos & derivados , Hormona Liberadora de Tirotropina/síntesis química , Hormona Liberadora de Tirotropina/farmacología , Administración Oral , Animales , Regulación de la Temperatura Corporal/efectos de los fármacos , Masculino , Prolina/administración & dosificación , Prolina/síntesis química , Prolina/química , Prolina/farmacología , Ratas Sprague-Dawley , Hormona Liberadora de Tirotropina/administración & dosificación , Hormona Liberadora de Tirotropina/química
7.
Int J Mol Sci ; 22(23)2021 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-34884483

RESUMEN

Cells for therapeutic use are often preserved at +4 °C, and the storage period is generally limited to 2-3 days. Here, we report that the survival rate (%) of mammalian cells is improved to 10-20 days when they are preserved with a subzero supercooled solution containing the antifreeze protein (AFP), for which an ability to stabilize both supercooled water and cell membrane integrity has been postulated. We chose adherent rat insulinoma (RIN-5F) cells as the preservation target, which were immersed into -5 °C-, -2 °C-, or +4 °C-chilled "unfrozen" solution of Euro-Collins or University of Washington (UW) containing the AFP sample obtained from insect or fish. Our results show that the survival rate of the cells preserved with the solution containing insect AFP was always higher than that of the fish AFP solution. A combination of the -5 °C-supercooling and insect AFP gave the best preservation result, namely, UW solution containing insect AFP kept 53% of the cells alive, even after 20 days of preservation at -5 °C. The insect AFP locates highly organized ice-like waters on its molecular surface. Such waters may bind to semiclathrate waters constructing both embryonic ice crystals and a membrane-water interface in the supercooled solution, thereby protecting the cells from damage due to chilling.


Asunto(s)
Proteínas Anticongelantes/administración & dosificación , Criopreservación/métodos , Crioprotectores/administración & dosificación , Hipotermia/tratamiento farmacológico , Proteínas de Insectos/administración & dosificación , Insulinoma/patología , Animales , Supervivencia Celular , Hielo , Insectos , Neoplasias Pancreáticas/patología , Ratas , Células Tumorales Cultivadas
8.
Stroke ; 51(2): 628-636, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31884905

RESUMEN

Background and Purpose- Induction of hypothermia as a stroke therapy has been limited by logistical challenges. This study was designed to determine the hypothermic and neuroprotective efficacy of infusing cold saline directly into the internal jugular (IJ) vein and compare the effects of IJ hypothermia to those achieved by intracarotid artery hypothermia in an ischemic stroke model. Methods- The right middle cerebral artery was occluded in rats using an intraluminal filament. Immediately following reperfusion, hypothermia was achieved by infusing isotonic saline through microcatheter into the right IJ or right intracarotid over 30 minutes. Infarct sizes, neurological deficits, blood-brain barrier damage, edema volume, blood-brain barrier associated molecules (MMP-9 [matrix metallopeptidase 9] and AQP-4 [aquaporin 4]), and apoptosis-associated proteins (Bcl-2 and cleaved Caspase-3) were measured. Results- We found that both IJ- and intracarotid-based infusion cooled the brain robustly with a minimal effect on rectal temperatures. This brain cooling led to significantly reduced infarct volumes at 24 hours after reperfusion, as well as decreased expression of the proapoptotic protein cleaved Caspase-3 and increased expression of the antiapoptotic protein Bcl-2. Intracarotid and IJ cooling also aided in blood-brain barrier maintenance, as shown by decreased edema volumes, reduced Evans Blue leakage, and decreased expression of edema-facilitating proteins (MMP-9 and AQP-4). Both cooling methods then translated to preserved neurological function as determined by multiple functional tests over a 28-day observation period. Most importantly, the cooling and neuroprotective efficacy of IJ cooling was comparable to intracarotid cooling by almost every metric evaluated. Conclusions- Compared with intracarotid infusion, IJ infusion conferred a similar degree of hypothermia and neuroprotection following ischemic stroke. Given the ease of establishing vascular access via the internal jugular vein and the powerful neuroprotection that hypothermia provides, IJ brain cooling could be used as a promising hypothermia-induction modality going forward.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Hipotermia/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Animales , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Hipotermia/metabolismo , Hipotermia Inducida/métodos , Infarto de la Arteria Cerebral Media/metabolismo , Ataque Isquémico Transitorio/tratamiento farmacológico , Masculino , Ratas Sprague-Dawley
9.
Molecules ; 25(6)2020 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-32178424

RESUMEN

As a Turkish traditional medicinal plant, aerial parts of Lotus corniculatus L. subsp. corniculatus (Fabaceae) are used as a painkiller, antihemoroidal, diuretic and sedative. In this study, the antidepressant potential of the plant has been attempted to clarify. Extracts with water, n-Hexane, ethyl acetate, and methanol were prepared respectively from the aerial parts. Antidepressant activity of the extracts were researched by using three different in vivo test models namely a tail suspension test, antagonism of tetrabenazine-induced hypothermia, ptosis, and suppression of locomotor activity and forced swimming test on male BALB/c mice and in vitro monoamine oxidase (MAO)-A and B inhibition assays. The results were evaluated through comparing with control and reference groups, and then active compounds of the active extract have been determined. Bioassay-guided fractionation of active fraction led to the isolation of three compounds and structures of the compounds were elucidated by spectroscopic methods. The data of this study demonstrate that the MeOH extract of the aerial parts of the plant showed remarkable in vivo antidepressant effect and the isolated compounds medicarpin-3-O-glucoside, gossypetin-3-O-glucoside and naringenin-7-O-glucoside (prunin) from the active sub-fractions could be responsible for the activity. Further mechanistic and toxicity studies are planned to develop new antidepressant-acting drugs.


Asunto(s)
Antidepresivos/farmacología , Hipotermia/tratamiento farmacológico , Lotus/química , Inhibidores de la Monoaminooxidasa/farmacología , Animales , Antidepresivos/química , Disacáridos/química , Disacáridos/aislamiento & purificación , Flavanonas/química , Flavanonas/aislamiento & purificación , Flavonoides/química , Flavonoides/aislamiento & purificación , Glucósidos/química , Glucósidos/aislamiento & purificación , Suspensión Trasera , Humanos , Hipotermia/inducido químicamente , Metanol/química , Ratones , Monoaminooxidasa , Inhibidores de la Monoaminooxidasa/química , Componentes Aéreos de las Plantas/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Pterocarpanos/química , Pterocarpanos/aislamiento & purificación , Tetrabenazina/toxicidad
10.
Mol Pharm ; 16(4): 1467-1476, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30821985

RESUMEN

Peptides are generally needed as T-helper epitopes in nicotine vaccines to induce effective antibody responses, but the highly polymorphic property of major histocompatibility complex (MHC) molecules may limit opportunities of B cell to receive CD4+ T-cell help. Invariant natural killer T (iNKT) cells recognize lipid antigens presented by the nonpolymorphic CD1d molecule that is conserved in mammals to a great extent. iNKT cells also display some similar functions to conventional CD4+ T-helper cells, especially they license dendritic cells stimulate antibody isotype switching by B cells. Herein, α-galactosylceramide (αGalCer), a classical iNKT cell agonist, serves as an adjuvant in synthetic nicotine vaccine candidates absent of peptide or protein. Our study reveals that αGalCer displays better adjuvant activity than Pam3CSK4 (a commonly used lipopeptide TLR agonist). Remarkably, the covalent linker between the nicotine hapten and αGalCer is not critical. Self-assembly of the lipid-tailed nicotine and αGalCer into the liposome represents a structurally simple but immunologically effective way to develop nicotine vaccines. This is the first time to introduce the iNKT cell agonist as an adjuvant to an antidrug vaccine. This discovery may contribute to improving the efficacy of clinical candidate nicotine vaccines in the future.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Analgésicos/administración & dosificación , Anticuerpos Monoclonales/inmunología , Galactosilceramidas/inmunología , Hipotermia/tratamiento farmacológico , Nicotina/administración & dosificación , Vacunas Sintéticas/administración & dosificación , Animales , Femenino , Galactosilceramidas/metabolismo , Hipotermia/inmunología , Hipotermia/metabolismo , Inmunización , Lipopéptidos/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Células T Asesinas Naturales/inmunología , Células T Asesinas Naturales/metabolismo , Nicotina/inmunología
11.
J Pept Sci ; 25(12): e3228, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31713944

RESUMEN

We discovered the orally active thyrotropin-releasing hormone (TRH) mimetic: (4S,5S)-5-methyl-N-{(2S)-1-[(2R)-2-methylpyrrolidin-1-yl]-1-oxo-3-(1,3-thiazol-4-yl)propan-2-yl}-2-oxo-1,3-oxazolidine-4-carboxamide 1 (rovatirelin). The central nervous system (CNS) effect of rovatirelin after intravenous (iv) administration is 100-fold higher than that of TRH. As 1 has four asymmetric carbons in its molecule, there are 16 stereoisomers. We synthesized and evaluated the anti-hypothermic effect of all stereoisomers of 1, which has the (4S),(5S),(2S),(2R) configuration from the N-terminus to the C-terminus, in order to clarify the structure-activity relationship (SAR) of stereoisomers. The (4R),(5R),(2R),(2S)-isomer 16 did not show any anti-hypothermic effect. Only the (4S),(5S),(2S),(2S)-isomer 10, which has the (2S)-2-methylpyrrolidine moiety at the C-terminus showed the anti-hypothermic effect similar to 1. Stereoisomers, which have the (5R) configuration of the oxazolidinone at the N-terminus and the (2R) configuration at the middle-part, showed a much lower anti-hypothermic effect than that of 1. On the other hand, stereoisomers, which have the (4R) configuration of the oxazolidinone at the N-terminus or the (2S) configuration of the C-terminus, have little influence on the anti-hypothermic effect.


Asunto(s)
Hipotermia/tratamiento farmacológico , Oxazolidinonas/síntesis química , Oxazolidinonas/uso terapéutico , Pirrolidinas/síntesis química , Pirrolidinas/uso terapéutico , Administración Intravenosa , Animales , Inyecciones Subcutáneas , Masculino , Ratones , Ratones Endogámicos , Estructura Molecular , Oxazolidinonas/química , Pirrolidinas/química , Estereoisomerismo
12.
Int J Hyperthermia ; 36(1): 1137-1146, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31744344

RESUMEN

Background: Because of the importance of adrenoreceptors in regulating the cardiovascular (CV) system and the role of the CV system in thermoregulation, understanding the response to these two stressors is of interest. The purpose of this study was to assess changes of arterial geometry and function in vivo during thermal and ß-adrenergic stress induced in mice and quantified by MRI.Methods: Male mice were anesthetized and imaged at 7 T. Anatomical and functional data were acquired from the neck (carotid artery), torso (suprarenal and infrarenal aorta and iliac artery) and periphery (femoral artery). Intravenous dobutamine (tail vein catheter, 40 µg/kg/min, 0.12 mL/h) was used as ß-adrenergic stressor. Baseline and dobutamine data were acquired at minimally hypothermic (35 °C) and minimally hyperthermic (38 °C) core temperatures. Cross-sectional vessel area and maximum cyclic strain were measured across the cardiac cycle.Results: Vascular response varied by location and by core temperature. For minimally hypothermic conditions (35 °C), average, maximum and minimum areas decreased with dobutamine only at the suprarenal aorta (avg: -17.9%, max: -13.5%, min: -21.4%). For minimally hyperthermic conditions (38 °C), vessel areas decreased between baseline and dobutamine at the carotid (avg: -19.6%, max: -15.5%, min: -19.3%) and suprarenal aorta (avg: -24.2%, max: -17.4%, min: -17.3%); whereas, only the minimum vessel area decreased for the iliac artery (min: -14.4%). Maximum cyclic strain increased between baseline and dobutamine at the iliac artery for both conditions and at the suprarenal aorta at hyperthermic conditions.Conclusions: At hypothermic conditions, the vessel area response to dobutamine is diminished compared to hyperthermic conditions where the vessel area response mimics normothermic dobutamine conditions. The varied response emphasizes the need to monitor and control body temperature during medical conditions or treatments that may be accompanied by hypothermia, especially when vasoactive agents are used.


Asunto(s)
Agonistas Adrenérgicos beta/uso terapéutico , Fiebre/tratamiento farmacológico , Hipotermia/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Masculino , Ratones
13.
Int J Mol Sci ; 20(10)2019 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-31109005

RESUMEN

Cold exposure stress causes hypothermia, cognitive impairment, liver injury, and cardiovascular diseases, thereby increasing morbidity and mortality. Paradoxically, cold acclimation is believed to confer metabolic improvement to allow individuals to adapt to cold, harsh conditions and to protect them from cold stress-induced diseases. However, the therapeutic strategy to enhance cold acclimation remains less studied. Here, we demonstrate that the mitochondrial-derived peptide MOTS-c efficiently promotes cold adaptation. Following cold exposure, the improvement of adipose non-shivering thermogenesis facilitated cold adaptation. MOTS-c, a newly identified peptide, is secreted by mitochondria. In this study, we observed that the level of MOTS-c in serum decreased after cold stress. MOTS-c treatment enhanced cold tolerance and reduced lipid trafficking to the liver. In addition, MOTS-c dramatically upregulated brown adipose tissue (BAT) thermogenic gene expression and increased white fat "browning". This effect might have been mediated by MOTS-c-activated phosphorylation of the ERK signaling pathway. The inhibition of ERK signaling disturbed the up-regulatory effect of MOTS-c on thermogenesis. In summary, our results indicate that MOTS-c treatment is a potential therapeutic strategy for defending against cold stress by increasing the adipose thermogenesis via the ERK pathway.


Asunto(s)
Respuesta al Choque por Frío/efectos de los fármacos , Hipotermia/tratamiento farmacológico , Péptidos/administración & dosificación , Péptidos/sangre , Termogénesis/efectos de los fármacos , Adaptación Fisiológica/efectos de los fármacos , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Hipotermia/sangre , Hipotermia/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Péptidos/farmacología , Fosforilación/efectos de los fármacos
14.
Paediatr Anaesth ; 28(1): 71-72, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29148139

RESUMEN

We describe the case of a 4-year-old child undergoing extensive burn surgery with refractory intraoperative hypothermia. A low-dose nitroglycerin infusion was initiated to reverse vasoconstriction and improve heat absorption, after which the child's temperature steadily improved. In hypothermic burn patients, topical vasoconstrictors may hinder surface warming efforts. A vasodilator infusion may aid in warming the pediatric patient undergoing extensive excision and grafting.


Asunto(s)
Quemaduras/complicaciones , Hipotermia/tratamiento farmacológico , Complicaciones Intraoperatorias/tratamiento farmacológico , Nitroglicerina/uso terapéutico , Vasodilatadores/uso terapéutico , Quemaduras/terapia , Preescolar , Humanos , Infusiones Intravenosas , Masculino
15.
J Therm Biol ; 78: 281-289, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30509649

RESUMEN

The aim of the present study was to investigate the effect of estradiol (E2) on thermoregulatory responses induced by menthol in ovariectomized rats. Wistar rats were ovariectomized, and implanted with a silastic tube with or without E2 (E2(+) and E2(-) groups). L-menthol (10%) or vehicle was applied to the skin of the whole trunk in selected animals, which were then exposed to 27 °C or 16 °C for 2 h. Continuous body temperature (Tb), tail skin temperature (Ttail), and treatment-associated behaviors were measured. cFos immunoreactive (cFos-IR) cells in the median preoptic area, paraventricular nucleus (PVN), medial preoptic area, posterior hypothalamus, and dorsomedial hypothalamus were counted. At 27 °C, in the E2(+) and E2(-) groups, the Tb and Ttail were greater in rats applied menthol than that in rats applied vehicle. In rats applied menthol, the Tb in the E2(+) group was lower than that in the E2(-) group. In the E2(+) and E2(-) groups, the number of cFos-IR cells in the PVN was greater in rats applied menthol than that in rats applied vehicle. These results suggested that menthol treatment increased Tb in ovariectomized rats with or without E2 at 27 °C, and that activation of the PVN might be involved in this response. E2 administration suppresses Tb elevation induced by application of menthol to ovariectomized rats.


Asunto(s)
Temperatura Corporal/efectos de los fármacos , Estradiol/farmacología , Hipotermia/tratamiento farmacológico , Animales , Femenino , Hipotermia/etiología , Mentol/farmacología , Ovariectomía , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Ratas , Ratas Wistar
16.
Bioorg Med Chem ; 25(24): 6597-6604, 2017 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-29137939

RESUMEN

Hypothermia has been proved to have a beneficial effect on several pathologies. CIRBP is one of the so termed cold-shock proteins involved in this process. In this work, we have detected small molecules capable of modulating the activity of CIRBP in the absence of a cold stimulus, by High Throughput Virtual Screening (HTVS) of the Diversity Set IV of the NCI and 15 compounds of our in-house data base. Fifteen compounds were selected from the HTVS to carry out a second screening through a cell-based Western blot assay. This assay, together with molecular modeling studies allowed us to select compound zr17-2 for an in vivo experiment, which showed an interesting increase of CIRBP expression in several organs of experimental animals. Therefore, we have demonstrated that the effect of hypothermia can be mimicked by small molecules, which can be developed as first-in-class new drugs for the treatment of several diseases.


Asunto(s)
Hipotermia/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Animales , Línea Celular , Proteínas y Péptidos de Choque por Frío/biosíntesis , Relación Dosis-Respuesta a Droga , Ensayos Analíticos de Alto Rendimiento , Hipotermia/metabolismo , Masculino , Modelos Moleculares , Estructura Molecular , Proteínas de Unión al ARN/biosíntesis , Ratas , Bibliotecas de Moléculas Pequeñas/síntesis química , Bibliotecas de Moléculas Pequeñas/química , Relación Estructura-Actividad
17.
Cryobiology ; 77: 75-81, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28479295

RESUMEN

BACKGROUND: Rewarming from hypothermia is associated with depressed cardiac function, known as hypothermia-induced cardiac dysfunction (HCD), and increased systemic vascular resistance (SVR). Previous studies on pharmacological treatment of HCD have demonstrated beneficial effects when using drugs with the combined effects; cardiac inotropic support and peripheral vasodilation. The presented study aims to investigate the isolated effects of arterial dilatation on cardiac functional variables during rewarming from hypothermia using sodium nitroprusside (SNP). METHODS: We utilized a rat model designed to induce HCD following 4 h at 15 °C and rewarming. To study effects on left ventricular (LV) functional variables in response to afterload reduction by SNP during rewarming a conductance catheter was used. Index of LV contractility, preload recruitable stroke work (PRSW), was obtained with inferior vena cava occlusions at 37 °C before and after hypothermia. Pressure signals from a catheter in the left femoral artery was used to pharmacologically adjust SVR. RESULTS: After rewarming both animal groups showed significant reduction in both SV and CO as a manifestation of HCD. However, compared to saline controls, SV and CO in SNP-treated animals increased significantly during rewarming in response to afterload reduction displayed as reduced SVR, mean arterial- and end-systolic pressures. The cardiac contractility variable PRSW was equally reduced after rewarming in both groups. CONCLUSION: When rewarming the present model of HCD a significant increase in SVR takes place. In this context, pharmacologic intervention aimed at reducing SVR show clear positive results on CO and SV. However, a reduction in SVR alone is not sufficient to fully alleviate CO during HCD, and indicate the need of additional inotropic support.


Asunto(s)
Hipotermia/tratamiento farmacológico , Nitroprusiato/uso terapéutico , Animales , Presión Sanguínea/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Arteria Femoral/efectos de los fármacos , Arteria Femoral/fisiología , Corazón/efectos de los fármacos , Hipotermia/fisiopatología , Masculino , Contracción Miocárdica/efectos de los fármacos , Nitroprusiato/farmacología , Ratas Wistar , Recalentamiento , Resistencia Vascular/efectos de los fármacos , Función Ventricular Izquierda/efectos de los fármacos
18.
Neurol India ; 65(6): 1304-1311, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29133706

RESUMEN

OBJECTIVE: Among newer neuroprotectant modalities, hypothermia and progesterone have shown a beneficial role in preliminary studies enrolling patients with severe traumatic brain injury (sTBI). The primary objective of this study was to evaluate the efficacy of progesterone with or without prophylactic hypothermia in acute sTBI patients. MATERIALS AND METHODS: This is a prospective, outcome assessor, statistician blinded, randomized, and placebo-controlled phase II trial of progesterone with or without hypothermia (factorial design). All adult patients (18-65 years) with acute sTBI (Glasgow coma score of 4-8) and presenting to trauma center within 8 h after injury were included in the trial. Computer-generated randomization was done after exclusion; sequentially numbered, opaque, sealed envelope technique was used for allocation concealment. The enrollment duration was from January 2012 to October 2014. The primary endpoint was dichotomized Glasgow outcome score (GOS) [poor recovery = GOS 1-3; good recovery = GOS 4-5], and secondary endpoints were functional independence measure (FIM) score and mortality rate at 6 and 12 months follow-up after recruitment. RESULTS: A total of 107 patients were randomized into four groups (placebo [n = 27], progesterone [n = 26], hypothermia alone [n = 27], and progesterone + hypothermia [n = 27]). The study groups were comparable in baseline parameters except for a higher incidence of decompressive craniectomy in the placebo group (P = 0.001). The analysis of GOS at 6 months revealed statistically significant better outcome in the hypothermia group (82%; P = 0.01) and a weaker evidence for progesterone group (74%; P = 0.07) as compared with the placebo group (44%). However, the outcome benefit was marginal at 1-year follow-up for the hypothermia group (82% vs. 58%, P = 0.17). The adjusted odds ratio of poor recovery at 6 months in the hypothermia group was 0.21 (confidence interval = 0.05-0.84, P = 0.03), as compared with the placebo group. Although mean FIM scores at 6 and 12 months respectively were marginally higher in the hypothermia and progesterone groups compared with the placebo group (P = 0.06 and 0.27), the proportion of functionally independent individuals were similar in all the groups (P = 0.79 and 0.51). The mortality rates were similar in all the groups at 6 and 12 months (P = 0.78 and 0.52 respectively). CONCLUSIONS: A strong evidence for prophylactic hypothermia and a weak evidence for progesterone therapy was observed for a better primary outcome at 6 months as compared to the placebo. A similar trend was observed at a 1-year follow-up. Contrary to our hypothesis, prophylactic hypothermia therapy suppressed the beneficial effects of progesterone therapy in sTBI patients. The complex cascades of factors responsible for such interactions are still unknown and need to be further determined.


Asunto(s)
Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Hipotermia/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Progesterona/uso terapéutico , Adulto , Lesiones Encefálicas/complicaciones , Lesiones Encefálicas/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/complicaciones , Craniectomía Descompresiva/métodos , Femenino , Escala de Coma de Glasgow , Humanos , Hipotermia/complicaciones , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
19.
AANA J ; 84(1): 23-6, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26939385

RESUMEN

Opioids have been administered intrathecally with subarachnoid block for postoperative pain relief in parturients undergoing elective cesarean deliveries. This case report presents the uncommon occurrence of intrathecal opioid-induced hypothermia in the latent phase of recovery following elective cesarean delivery. There are few case reports on the occurrence of latent-phase postanesthesia care hypothermia in patients receiving subarachnoid block with morphine sulfate injection (Duramorph). Hypothermia can occur postoperatively for many reasons and can be life-threatening. In this case, hypothermia developed and progressed throughout the postoperative period. The causes of hypothermia were evaluated and treated without success initially. Thyroid dysfunction and alternative differential diagnoses were ruled out. Further assessment determined that the morphine injection might have been a contributing factor. Naloxone at 40-µg increments was administered intravenously and corrected the hypothermia. Awareness of hypothermia postoperatively with associated morphine administration through subarachnoid block must be ruled out in cases of progressing hypothermia.


Asunto(s)
Anestesia Epidural/efectos adversos , Cesárea , Procedimientos Quirúrgicos Electivos/efectos adversos , Hipotermia/inducido químicamente , Hipotermia/tratamiento farmacológico , Morfina/efectos adversos , Dolor Postoperatorio/tratamiento farmacológico , Adulto , Anestesia Obstétrica/efectos adversos , Femenino , Humanos , Embarazo , Resultado del Tratamiento
20.
Orv Hetil ; 157(7): 275-8, 2016 Feb 14.
Artículo en Húngaro | MEDLINE | ID: mdl-26853729

RESUMEN

Anomalies of the corpus callosum are the most frequent malformations of the central nervous system. The triad of spontaneous periodic hypothermia and hyperhydrosis with the agenesis of corpus callosum is described as Shapiro syndrome. Shapiro syndrome is a very rare condition and it can occur in every age group. The presence of agenesis of corpus callosum is not a strict criteria of the syndrome; the most important presenting symptom is paroxysmal hypothermia. Although the definite cause of recurrent hypothermia is unknown, dysfunction of the hypothalamus is suspected. From therapeutic aspects, only supportive therapy is available. In this report the authors present the first Shapiro syndrome case diagnosed in Hungary. The main symptoms of the 21-year-old male patient were recurrent hyperhydrosis with hypothermia resulting in severe general malaise. The skull magnetic resonance imaging demonstrated agenesis of corpus callosum. The patient was treated with clonidine resulting in significant improvement of symptoms.


Asunto(s)
Agenesia del Cuerpo Calloso/complicaciones , Regulación de la Temperatura Corporal , Cuerpo Calloso/patología , Hiperhidrosis/etiología , Hipotermia/etiología , Agenesia del Cuerpo Calloso/etiología , Agenesia del Cuerpo Calloso/patología , Agenesia del Cuerpo Calloso/fisiopatología , Regulación de la Temperatura Corporal/efectos de los fármacos , Clonidina/uso terapéutico , Cuerpo Calloso/fisiopatología , Humanos , Hungría , Hiperhidrosis/complicaciones , Hiperhidrosis/patología , Hipotermia/complicaciones , Hipotermia/tratamiento farmacológico , Hipotermia/patología , Imagen por Resonancia Magnética , Masculino , Adulto Joven
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