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1.
Int J Mol Sci ; 24(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37834299

RESUMO

Alzheimer disease (AD) is a widespread neurodegenerative disease characterized by the accumulation of oligomeric toxic forms of ß-amyloid (Aß1-42) and dysfunction of the cholinergic system in the different brain regions. However, the exact mechanisms of AD pathogenesis and the role of the nicotinic acetylcholine receptors (nAChRs) in the disease progression remain unclear. Here, we revealed a decreased expression of a number of the Ly6/uPAR proteins targeting nAChRs in the cerebellum of 2xTg-AD mice (model of early AD) in comparison with non-transgenic mice both at mRNA and protein levels. We showed that co-localization of one of them, - neuromodulator Lynx1, with α7-nAChR was diminished in the vicinity of cerebellar astrocytes of 2xTg-AD mice, while Aß1-42 co-localization with this receptor present was increased. Moreover, the expression of anti-inflammatory transcription factor KLF4 regulating transcription of the Ly6/uPAR genes was decreased in the cerebellum of 2xTg-AD mice, while expression of inflammatory cytokine TNF-α was increased. Based on these data together with observed astrocyte degeneration in the cerebellum of 2xTg-AD mice, we suggest the mechanism by which expression of the Ly6/uPAR proteins upon Aß pathology results in dysregulation of the cholinergic system and particularly of α7-nAChR function in the cerebellum. This leads to enhanced neuroinflammation and cerebellar astrocyte degeneration.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Receptores Nicotínicos , Camundongos , Animais , Doença de Alzheimer/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Astrócitos/metabolismo , Doenças Neurodegenerativas/metabolismo , Peptídeos beta-Amiloides/metabolismo , Receptores Nicotínicos/metabolismo , Cerebelo/metabolismo , Colinérgicos/metabolismo
2.
Behav Brain Res ; 419: 113682, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34843743

RESUMO

Profound effects of spaceflight on the physiology of humans and non-human animals are well-documented but incompletely explored. Current goals to undertake interplanetary missions increase the urgency to learn more about adaptation to prolonged spaceflight and readaptation to Earth-normal conditions, especially with the inclusion of radiation exposures greater than those confronted in traditional, orbital flights. The 30-day-long Bion M-1 biosatellite flight was conducted at a relatively high orbit, exposing the mice to greater doses of radiation in addition to microgravity, a combination of factors relevant to Mars missions. Results of the present studies with mice provide insights into the consequences on brain function of long-duration spaceflight. After landing, mice showed profound deficits in vestibular responses during aerial drop tests. Spaceflown mice displayed reduced grip strength, rotarod performance, and voluntary wheel running, each, which improved gradually but incompletely over the 7-days of post-flight testing. Continuous monitoring in the animals' home cage activity, in combination with open-field and other tests of motor performance, revealed indices of altered affect, expressed as hyperactivity, potentiated thigmotaxis, and avoidance of open areas which, together, presented a syndrome of persistent anxiety-like behavior. A learned, operant response acquired before spaceflight was retained, whereas the acquisition of a new task was impaired after the flight. We integrate these observations with other results from Bion-M1's program, identifying deficits in musculoskeletal and cardiovascular systems, as well as in the brain and spinal cord, including altered gene expression patterns and the accompanying neurochemical changes that could underlie our behavioral findings.


Assuntos
Comportamento Animal/fisiologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Radiação Cósmica/efeitos adversos , Desempenho Psicomotor/fisiologia , Voo Espacial , Ausência de Peso/efeitos adversos , Animais , Camundongos
3.
J Pharmacol Toxicol Methods ; 113: 107128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34678429

RESUMO

Metabolic chambers are routinely used for urine collection in rodents. In mice, due to small urination volume, evaporation in the metabolic chambers (≈50%) distorts diuresis and urinalysis parameters. We have developed a new technique of bladder catheterization enabling long-term accurate and contamination-free urine collection in awake male and female mice for 30 days or longer. Daily diuresis in catheterized mice was twice higher as compared to metabolic cages. The twofold difference in urine recovery was preserved when the circadian variation of diuresis, the effects of furosemide, desmopressin and water load were estimated using the two techniques. Urine osmolarity, urinalysis, and microbiological parameters evidence higher quality of the catheter-collected urine. Using phenol red, we demonstrate utility of our technique for pharmacokinetic studies. 30 days after the surgery the catheters were patent and had minimal impact on the animals' heath. Bladder catheterization is a useful tool for physiological, pharmacological, and toxicological studies.


Assuntos
Bexiga Urinária , Coleta de Urina , Animais , Diurese , Feminino , Masculino , Camundongos , Cateterismo Urinário , Vigília
4.
Front Pharmacol ; 12: 679511, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34413772

RESUMO

Kagocel is a synthetic carboxymethylcellulose derivative copolymerized with gossypol. Clinical data evidence its safety and efficiency for the treatment of flu and other viral infections via enhancement of interferon production. The gut-associated lymphoid tissue seems a likely site of kagocel action. The study was aimed to investigate the molecular mechanisms of its action using murine Peyer's patches lymphocytes as a test system and the cytokines production and gene expression patterns as the primary outcomes. The Peyer's patches lymphocytes isolated from BALB/c mice were stimulated with concanavalin A, or, to mimic viral infection, with a combination of concanavalin A and TLR3 ligand poly I:C. After 24 h of stimulation the cells were treated with saline, 30, 100, or 300 µg/ml of kagocel, or, as positive controls, 300 µg/ml oats b-D-glucan or 300 µg/ml lentinan. After 24 and 72 h of incubation with these drugs cytokines production was analyzed with ELISA and gene expression pattern was investigated using nCounter Inflammation panel chips followed by bioinformatics analysis. Expression of genes involved in the inflammatory response, antiviral defense, lymphocytes survival and proliferation (C1qa, C2, C3, Ccl21a, Il11, Il1b, Il23a, Il5, Ltb4r2, Alox15, Pla2g4a, Ptger1, Mapkapk5, Hras, Ifna1, Tlr2, Mrc1, Mx2) was upregulated in kagocel-treated Peyer's patches lymphocytes. A list of plausible transcription factors (CEBPs, IRF, NFκB, RXR, Stat, Tead4, and ZSCAN) and master-regulators has been identified (cIAP, CIKS, dock9, MEKK1, FXR, IKK, IRAK, TRAF, dsRNA:TLR3:TRIF). The changes in gene expression pattern and the outcomes of bioinformatics analysis suggest that pattern recognition receptors, TLRs and dectin-1, are the key mediators of kagocel immunomodulatory action, with the possible involvement of interferon autocrine loop. The genes upregulated with kagocel include diverse components of the innate immune defense system.

5.
FEBS J ; 288(7): 2418-2435, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33051988

RESUMO

Venoms are a rich source of highly specific toxins, which allow the identification of novel therapeutic targets. We have now applied high content screening (HCS) microscopy to identify toxins that modulate pain sensitization signaling in primary sensory neurons of rat and elucidated the underlying mechanism. A set of venoms and fractions thereof were analyzed for their ability to activate type II protein kinase A (PKA-II) and extracellular signal-regulated kinases (ERK1/2). We identified MeuNaTxα-1, a sodium channel-selective scorpion α-toxin from Mesobuthus eupeus, which affected both PKA-II and ERK1/2. Recombinant MeuNaTxα-1 showed identical activity to the native toxin on mammalian voltage-gated sodium channels expressed in Xenopus laevis oocytes and induced thermal hyperalgesia in adult mice. The effect of MeuNaTxα-1 on sensory neurons was dose-dependent and tetrodotoxin-sensitive. Application of inhibitors and toxin mutants with altered sodium channel selectivity demonstrated that signaling activation in sensory neurons depends on NaV 1.2 isoform. Accordingly, the toxin was more potent in neurons from newborn rats, where NaV 1.2 is expressed at a higher level. Our results demonstrate that HCS microscopy-based monitoring of intracellular signaling is a novel and powerful tool to identify and characterize venoms and their toxins affecting sensory neurons.


Assuntos
Proteína Quinase Tipo II Dependente de AMP Cíclico/genética , Canal de Sódio Disparado por Voltagem NAV1.2/genética , Dor/genética , Canais de Sódio Disparados por Voltagem/genética , Animais , Animais Recém-Nascidos , Humanos , Hiperalgesia/genética , Hiperalgesia/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Oócitos/efeitos dos fármacos , Oócitos/crescimento & desenvolvimento , Ratos , Venenos de Escorpião/química , Venenos de Escorpião/farmacologia , Escorpiões/química , Células Receptoras Sensoriais , Xenopus laevis/crescimento & desenvolvimento
6.
Materials (Basel) ; 13(15)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32751921

RESUMO

Here we evaluated the efficacy of bone repair using various native bovine biomaterials (refined hydroxyapatite (HA), demineralised bone matrix (DBM), and purified bone collagen (COLL)) as compared with commercially available bone mineral and bone autografts. We employed a conventional critical-sized (8 mm diameter) rat calvarial defect model (6-month-old male Sprague-Dawley rats, n = 72 in total). The artificial defect was repaired using HA, DBM, COLL, commercially available bone mineral powder, bone calvarial autograft, or remained unfilled (n = 12 animals per group). Rats were euthanised 4 or 12 weeks postimplantation (n = 6 per time point) with the subsequent examination to assess the extent, volume, area, and mineral density of the repaired tissue by means of microcomputed tomography and hematoxylin and eosin staining. Bovine HA and DBM powder exhibited excellent repair capability similar to the autografts and commercially available bone mineral powder while COLL showed higher bone repair rate. We suggest that HA and DBM powder obtained from bovine bone tissue can be equally applied for the repair of bone defects and demonstrate sufficient potential to be implemented into clinical studies.

7.
J Neurochem ; 155(1): 45-61, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32222974

RESUMO

Lynx1 is a GPI-tethered protein colocalized with nicotinic acetylcholine receptors (nAChRs) in the brain areas important for learning and memory. Previously, we demonstrated that at low micromolar concentrations the water-soluble Lynx1 variant lacking GPI-anchor (ws-Lynx1) acts on α7-nAChRs as a positive allosteric modulator. We hypothesized that ws-Lynx1 could be used for improvement of cognitive processes dependent on nAChRs. Here we showed that 2 µM ws-Lynx1 increased the acetylcholine-evoked current at α7-nAChRs in the rat primary visual cortex L1 interneurons. At higher concentrations ws-Lynx1 inhibits α7-nAChRs expressed in Xenopus laevis oocytes with IC50  ~ 50 µM. In mice, ws-Lynx1 penetrated the blood-brain barrier upon intranasal administration and accumulated in the cortex, hippocampus, and cerebellum. Chronic ws-Lynx1 treatment prevented the olfactory memory and motor learning impairment induced by the α7-nAChRs inhibitor methyllycaconitine (MLA). Enhanced long-term potentiation and increased paired-pulse facilitation ratio were observed in the hippocampal slices incubated with ws-Lynx1 and in the slices from ws-Lynx1-treated mice. Long-term potentiation blockade observed in MLA-treated mice was abolished by ws-Lynx1 co-administration. To understand the mechanism of ws-Lynx1 action, we studied the interaction of ws-Lynx1 and MLA at α7-nAChRs, measured the basal concentrations of endogenous Lynx1 and the α7 nAChR subunit and their association in the mouse brain. Our findings suggest that endogenous Lynx1 limits α7-nAChRs activation in the adult brain. Ws-Lynx1 partially displaces Lynx1 causing positive modulation of α7-nAChRs and enhancement of synaptic plasticity. Ws-Lynx1 and similar compounds may constitute useful hits for treatment of cognitive deficits associated with the cholinergic system dysfunction.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/farmacologia , Inibidores da Colinesterase/toxicidade , Disfunção Cognitiva/prevenção & controle , Disfunção Cognitiva/psicologia , Plasticidade Neuronal/efeitos dos fármacos , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Acetilcolina/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/farmacocinética , Alcaloides/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/metabolismo , Disfunção Cognitiva/induzido quimicamente , Interneurônios/efeitos dos fármacos , Aprendizagem/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Wistar , Olfato/efeitos dos fármacos , Córtex Visual/efeitos dos fármacos , Xenopus laevis
8.
J Neurosci Methods ; 329: 108457, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31614160

RESUMO

BACKGROUND: Photothrombosis is a minimally invasive method for induction of cortical ischemia. However, different ways of applying some methods to assess photothrombosis-induced damage need to be developed. NEW METHODS: We applied the tongue protrusion test and H&E staining of brain sections to detect ischemic damage after photothrombosis. Evaluation of the local status of the BBB using Evans blue dye was proposed. We also assessed the sensitivity of the grid-walk test. Moreover, we examined the interchangeability of MRI and TTC staining to measure lesion volume. RESULTS: We evaluated ischemic outcomes at 24 h after photothrombosis in mice. The tongue protrusion test did not reveal impairments of the neurological status whereas the grid-walk test showed the high sensitivity. Using histological techniques, we determined the reduction in the number of neurons with normal morphology in the penumbra. 3D reconstruction of the brain, which reflected Evans blue dye distribution in the nervous tissue, revealed BBB disruption in areas remote from the ischemic core. We also showed the strong correlation between damage volumes assessed by MRI and TTC staining. COMPARISON WITH EXISTING METHODS: The present work demonstrates the efficacy of the classical histological approach and TTC staining that are more affordable than MRI and immunohistochemical methods. Detection of 3D distribution of Evans blue dye in the brain in contrast to its total extraction reveals BBB damage in details. CONCLUSIONS: We proposed the simple methods for describing the severity of brain ischemia at the cellular and whole organism levels without significant labor and financial expenditures.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/patologia , Corantes , Trombose Intracraniana/complicações , Imageamento por Ressonância Magnética , Atividade Motora/fisiologia , Córtex Sensório-Motor/patologia , Coloração e Rotulagem , Animais , Comportamento Animal/fisiologia , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/etiologia , Modelos Animais de Doenças , Amarelo de Eosina-(YS) , Hematoxilina , Imageamento por Ressonância Magnética/economia , Imageamento por Ressonância Magnética/normas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Córtex Sensório-Motor/diagnóstico por imagem , Coloração e Rotulagem/economia , Coloração e Rotulagem/métodos , Coloração e Rotulagem/normas , Sais de Tetrazólio , Caminhada/fisiologia
9.
J Exp Biol ; 221(Pt 17)2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-29950449

RESUMO

The cardiovascular system is adapted to gravity, and reactions to the loss of gravity in space are presumably dependent on body size. The dependence of hematological parameters and body fluid volume on simulated microgravity have never been studied as an allometric function before. Thus, we estimated red blood cell (RBC), blood and extracellular fluid volume in hindlimb-unloaded (HLU) or control (attached) mice, rats and rabbits. RBC decrease was found to be size independent, and the allometric dependency for RBC loss in HLU and control animals shared a common power (-0.054±0.008) but a different Y0 coefficient (8.66±0.40 and 10.73±0.49, respectively, P<0.05). Blood volume in HLU animals was unchanged compared with that of controls, disregarding body size. The allometric dependency of interstitial fluid volume in HLU and control mice shared Y0 (1.02±0.09) but had different powers N (0.708±0.017 and 0.648±0.016, respectively, P<0.05), indicating that the interstitial fluid volume increase during hindlimb unloading is more pronounced in larger animals. Our data underscore the importance of size-independent mechanisms of cardiovascular adaptation to weightlessness. Despite the fact that the use of mice hampers application of a straightforward translational approach, this species is useful for gravitational biology as a tool to investigate size-independent mechanisms of mammalian adaptation to microgravity.


Assuntos
Líquidos Corporais/fisiologia , Tamanho Corporal , Deslocamentos de Líquidos Corporais/fisiologia , Elevação dos Membros Posteriores/fisiologia , Simulação de Ausência de Peso , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Coelhos , Ratos , Ratos Wistar , Ausência de Peso
10.
BMC Urol ; 18(1): 36, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29739451

RESUMO

BACKGROUND: Penile erection is a complex reflex under spinal control and modulated by the brain. The hemodynamic events under autonomic control and the perineal muscles somatic activity are interconnected during the reflex erection at the spinal level, however if the afferent feedback on the corpus cavernosum pressure during an erection affects the somatic activity (perineal muscles contractions) and vice versa is not known. This study was aimed to test this hypothesis using a rat model. METHODS: Intracavernous pressure (ICP) and bulbocavernosus (BC) muscle EMG were recorded during reflex erections elicited with dorsal penile nerve (DNP) electrical stimulation in anaesthetized acutely spinalized SD rats with surgically (bilateral cavernous nerve section, CnX, n = 8) and pharmacologically (trimetaphan infusion, TMPh, n = 8) abolished pressor response, or with surgically (bilateral section of the motor branch of the pudendal nerve, PnX, n = 7) and pharmacologically (1 mg/kg d-tubocurarine, n = 8) blocked perineal muscles contractions, or with interrupted afferent input from the penis (bilateral crush of the dorsal penile nerve, DPnX, n = 7). Control rats (n = 8) received no intervention. RESULTS: Moderate positive correlations were found between net parameters of pressor and somatic activity during DNP-stimulation induced reflex erection in spinal rats, particularly the speed of pressor response development was positively correlated to EMG parameters. No changes of EMG activity were found in CnX rats, while the decrease of BC EMG in TMPh-treated males can be attributed to direct inhibitory action of TMPh on neuromuscular transmission. Pressor response latency was increased and ICP front slope decreased in dTK and PnX rats, indicating that perineal muscles contraction augment pressor response. DPN crush had little effect on ICP and EMG. CONCLUSION: Afferent input on the level of intracavernous pressure and the perineal muscles activity has minimal impact on, correspondingly, the somatic and the autonomic components of the reflex erection in spinal males, once the reflex has been initiated.


Assuntos
Hemodinâmica/fisiologia , Músculo Esquelético/fisiologia , Ereção Peniana/fisiologia , Reflexo/fisiologia , Animais , Estimulação Elétrica/métodos , Eletromiografia/métodos , Masculino , Músculo Esquelético/inervação , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
11.
FASEB J ; 31(12): 5466-5477, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28821629

RESUMO

Mechanical loading is necessary for the development and maintenance of the musculoskeletal system. Removal of loading via microgravity, paralysis, or bed rest leads to rapid loss of muscle mass and function; however, the molecular mechanisms that lead to these changes are largely unknown, particularly for the spaceflight (SF) microgravity environment. Furthermore, few studies have explored these effects on the shoulder, a dynamically stabilized joint with a large range of motion; therefore, we examined the effects of microgravity on mouse shoulder muscles for the 15-d Space Transportation System (STS)-131, 13-d STS-135, and 30-d Bion-M1 missions. Mice from STS missions were euthanized within 4 h after landing, whereas mice from the Bion-M1 mission were euthanized within 14 h after landing. The motion-generating deltoid muscle was more sensitive to microgravity than the joint-stabilizing rotator cuff muscles. Mice from the STS-131 mission exhibited reduced myogenic (Myf5 and -6) and adipogenic (Pparg, Cebpa, and Lep) gene expression, whereas either no change or an increased expression of these genes was observed in mice from the Bion-M1 mission. In summary, muscle responses to microgravity were muscle-type specific, short-duration SF caused dramatic molecular changes to shoulder muscles and responses to reloading upon landing were rapid.-Shen, H., Lim, C., Schwartz, A. G., Andreev-Andrievskiy, A., Deymier, A. C., Thomopoulos, S. Effects of spaceflight on the muscles of the murine shoulder.


Assuntos
Músculo Esquelético/metabolismo , Voo Espacial , Animais , Peso Corporal/genética , Peso Corporal/fisiologia , Feminino , Masculino , Camundongos , Fator Regulador Miogênico 5/genética , Fator Regulador Miogênico 5/metabolismo , Fatores de Regulação Miogênica/genética , Fatores de Regulação Miogênica/metabolismo , Proteômica , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Manguito Rotador/metabolismo , Ombro , Ausência de Peso , Microtomografia por Raio-X
12.
Toxicon ; 138: 59-67, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28811247

RESUMO

Bites of tiger spiders belonging to Poecilotheria genus cause moderate to severe pain and long-lasting local or generalized muscle cramps in humans. Bites occur in regions of the spiders' natural habitat, India and Sri Lanka, but the popularity of these colorful tarantulas as pets leads to reports of envenomation cases worldwide. Treatment is predominantly symptomatic and often inadequate since there is almost no clinical or toxicology research data available, and physicians outside India or Sri Lanka typically have no experience in treating such cases. We report toxicity studies of venom from nine Poecilotheria species in laboratory mice (Mus musculus Balb/C males). LD50 values are 5-14 mg of lyophilized crude venom per 1 kg (i.v.). The major symptoms of envenomation include tonic-clonic seizures, jerks, characteristic motor stereotypy, and hyperalgesia and point to voltage-gated sodium channels as a potential target of the venom components. Poecilotheria fasciata venom effects were studied in detail at a sub-lethal dose of 5 mg/kg (LD50 = 12 mg/kg). 13 widely used pharmacological agents (atropine, chloropyramine, chlorpromazine, diazepam, ethanol, flupirtine, haloperidol, ketotifen, lamotrigine, oxcarbazepine, tolperisone, xylazine, and CaCl2) were checked for ability to suppress the envenomation symptoms. Chlorpromazine (10 mg/kg, i.p.), oxcarbazepine (60 mg/kg, p.o.), tolperisone (50 mg/kg, s.c.) and xylazine (2.5 mg/kg, i.p.) were found effective as a pretreatment to mitigate muscle cramps and motor stereotypy. When administered after envenomation chlorpromazine (5 mg/kg, i.v.) effectively reduced the cramps, while oxcarbazepine (30 mg/kg, i.v.) and xylazine (1 mg/kg, i.v.) suppressed the stereotypy.


Assuntos
Cãibra Muscular/tratamento farmacológico , Picada de Aranha/tratamento farmacológico , Venenos de Aranha/toxicidade , Transtorno de Movimento Estereotipado/tratamento farmacológico , Animais , Clorpromazina/farmacologia , Hiperalgesia , Masculino , Camundongos Endogâmicos BALB C , Oxcarbazepina/farmacologia , Convulsões , Canais de Sódio Disparados por Voltagem , Xilazina/farmacologia
13.
Life Sci Space Res (Amst) ; 13: 19-26, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28554506

RESUMO

Animals are an essential component of space exploration and have been used to demonstrate that weightlessness does not disrupt essential physiological functions. They can also contribute to space research as models of weightlessness-induced changes in humans. Animal research was an integral component of the 30-day automated Russian biosatellite Bion-M 1 space mission. The aim of the hemodynamic experiment was to estimate cardiovascular function in mice, a species roughly 3000 times smaller than humans, during prolonged spaceflight and post-flight recovery, particularly, to investigate if mice display signs of cardiovascular deconditioning. For the first time, heart rate (HR) and blood pressure (BP) were continuously monitored using implantable telemetry during spaceflight and recovery. Decreased HR and unchanged BP were observed during launch, whereas both HR and BP dropped dramatically during descent. During spaceflight, BP did not change from pre-flight values. However, HR increased, particularly during periods of activity. HR remained elevated after spaceflight and was accompanied by increased levels of exercise-induced tachycardia. Loss of three of the five mice during the flight as a result of the hardware malfunction (unrelated to the telemetry system) and thus the limited sample number constitute the major limitation of the study. For the first time BP and HR were continuously monitored in mice during the 30-day spaceflight and 7-days of post-flight recovery. Cardiovascular deconditioning in these tiny quadruped mammals was reminiscent of that in humans. Therefore, the loss of hydrostatic pressure in space, which is thought to be the initiating event for human cardiovascular adaptation in microgravity, might be of less importance than other physiological mechanisms. Further experiments with larger number of mice are needed to confirm these findings.


Assuntos
Determinação da Pressão Arterial/métodos , Sistema Cardiovascular , Voo Espacial , Adaptação Fisiológica , Animais , Frequência Cardíaca , Hemodinâmica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Telemetria
14.
Artigo em Inglês | MEDLINE | ID: mdl-28167230

RESUMO

INTRODUCTION: Implantable telemetry enables continuous monitoring of physiological functions in freely moving animals and can greatly complement pharmacological research. Despite its miniaturization, a sensor/transmitter constitutes 5% or more of a mouse's bodyweight. The aim of the present study was to evaluate whether factors related to the presence of a probe/transmitter influence the ambulatory activity, strength, agility, or operant, motivated behaviors of this small rodent. METHODS: Adult male mice (C57BL/6N, 22-25g, 9-10weeks; implanted n=26, intact n=45) were evaluated during week-long tests, conducted three and eight weeks after surgical implantation of the PA-C10 blood pressure probe. An open field test, grip force measurement, Rotarod test were performed, followed by 7-day continuous monitoring of spontaneous wheel running activity and positively reinforced operant conditioning in an automated data collection system. RESULTS: An implanted blood pressure transmitter did not affect behavior of mice in the open field test, on the Rotarod or their grip force, compared to unoperated controls. Voluntary wheel running distance was reduced three, but not eight weeks after implantation. Three weeks after the surgery, performance in the positively reinforced operant conditioning in operated mice was slightly decreased compared to intact animals, while retention and acquisition of a 2nd, reversal-learning task eight weeks after the surgery were unaffected. DISCUSSION: We conclude that an implantable transmitter may have detectable effects in the first few weeks following implantation on some elements of mouse behavior. With sufficient recovery, mice perform comparably to unoperated controls in tests of strength, endurance, agility and learned operant behavior.


Assuntos
Adaptação Fisiológica/fisiologia , Pressão Sanguínea/fisiologia , Condicionamento Operante/fisiologia , Aprendizagem/fisiologia , Locomoção/fisiologia , Telemetria/métodos , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Telemetria/instrumentação
15.
J Sex Med ; 14(3): 336-346, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28189563

RESUMO

INTRODUCTION: Low sexual desire is a frequent sexual problem in women, with only one drug for the condition approved by the Food and Drug Administration. AIM: To evaluate the ability of a novel synthetic peptide, BP101, to facilitate sexual behavior after intranasal administration or infusion into certain brain areas in female rats. METHODS: Bilaterally ovariectomized female rats, primed with a suboptimal combination of estradiol benzoate (EB) and progesterone, were used as a model of low sexual motivation. Sexual behavior was tested with stud male rats after acute (experiment 1) or long-term (experiment 2) intranasal administration of BP101 or peptide infusion into the olfactory bulb, medial preoptic area, ventromedial hypothalamic nucleus, or ventral tegmental area (experiment 3). MAIN OUTCOME MEASURES: Frequency of solicitations (SF), as an indicator of sexual motivation in female rats, and lordosis frequency and ratio, as measurements of female consummatory sexual behavior. RESULTS: Acute intranasal BP101 administration moderately increased SF, with the highest tested dose of 300 µg/kg causing an 80% increase. Female rats receiving BP101 75 or 300 µg/kg daily on days 6 to 16 of the peptide administration displayed twofold higher SF compared with the placebo-treated animals, an increase comparable to optimally hormone-primed female rats. Infusion of BP101 1 and 5 µg per rat into the medial preoptic area, but not into the olfactory bulb, ventromedial hypothalamic nucleus, or ventral tegmental area, increased SF in female rats supplemented with EB 10 or 20 µg. The effect was relatively more pronounced in female rats receiving EB 10 µg (≈300%) compared with EB 20 µg (≈50%) with direct brain infusions. CONCLUSION: BP101 displays a potent stimulatory effect on sexual motivation in the female rat, and the medial preoptic area seems to be the site of its action. BP101 is effective in female rats receiving different hormone supplementations, making the present data generalizable to pre- and postmenopausal women with hypoactive sexual desire. Andreev-Andrievskiy A, Lomonosov M, Popova A, et al. BP101 Peptide Promotes Female Sexual Receptivity in the Rat. J Sex Med 2017;14:336-346.


Assuntos
Copulação/efeitos dos fármacos , Estradiol/análogos & derivados , Peptídeos/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Animais , Estradiol/farmacologia , Feminino , Área Pré-Óptica , Progesterona/farmacologia , Ratos
16.
Oxid Med Cell Longev ; 2016: 8703645, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293517

RESUMO

Rheumatoid arthritis is one of the most common autoimmune diseases. Many antioxidants have been tested in arthritis, but their efficacy was, at best, marginal. In this study, a novel mitochondria-targeted antioxidant, plastoquinonyl-decyl-triphenylphosphonium bromide (SkQ1), was tested in vivo to prevent and cure experimental autoimmune arthritis. In conventional Wistar rats, SkQ1 completely prevented the development of clinical signs of arthritis if administered with food before induction. Further, SkQ1 significantly reduced the fraction of animals that developed clinical signs of arthritis and severity of pathological lesions if administration began immediately after induction of arthritis or at the onset of first symptoms (day 14 after induction). In specific pathogen-free Wistar rats, SkQ1 administered via gavage after induction of arthritis did not reduce the fraction of animals with arthritis but decreased the severity of lesions upon pathology examination in a dose-dependent manner. Efficacious doses of SkQ1 were in the range of 0.25-1.25 nmol/kg/day (0.13-0.7 µg/kg/day), which is much lower than doses commonly used for conventional antioxidants. SkQ1 promoted apoptosis of neutrophils in vitro, which may be one of the mechanisms underlying its pharmacological activity. Considering its low toxicity and the wide therapeutic window, SkQ1 may be a valuable additional therapy for rheumatoid arthritis.


Assuntos
Antioxidantes/farmacologia , Antirreumáticos/farmacologia , Artrite Experimental/prevenção & controle , Articulações/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Plastoquinona/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Artrite Experimental/induzido quimicamente , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Linhagem Celular , Colágeno Tipo II , Relação Dose-Resposta a Droga , Humanos , Articulações/imunologia , Articulações/metabolismo , Articulações/patologia , Mitocôndrias/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/patologia , Plastoquinona/farmacologia , Ratos Wistar , Fatores de Tempo
17.
PLoS One ; 9(8): e104830, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25133741

RESUMO

After a 16-year hiatus, Russia has resumed its program of biomedical research in space, with the successful 30-day flight of the Bion-M 1 biosatellite (April 19-May 19, 2013). The principal species for biomedical research in this project was the mouse. This paper presents an overview of the scientific goals, the experimental design and the mouse training/selection program. The aim of mice experiments in the Bion-M 1 project was to elucidate cellular and molecular mechanisms, underlying the adaptation of key physiological systems to long-term exposure in microgravity. The studies with mice combined in vivo measurements, both in flight and post-flight (including continuous blood pressure measurement), with extensive in vitro studies carried out shortly after return of the mice and in the end of recovery study. Male C57/BL6 mice group housed in space habitats were flown aboard the Bion-M 1 biosatellite, or remained on ground in the control experiment that replicated environmental and housing conditions in the spacecraft. Vivarium control groups were used to account for housing effects and possible seasonal differences. Mice training included the co-adaptation in housing groups and mice adaptation to paste food diet. The measures taken to co-adapt aggressive male mice in housing groups and the peculiarities of "space" paste food are described. The training program for mice designated for in vivo studies was broader and included behavioral/functional test battery and continuous behavioral measurements in the home-cage. The results of the preliminary tests were used for the selection of homogenous groups. After the flight, mice were in good condition for biomedical studies and displayed signs of pronounced disadaptation to Earth's gravity. The outcomes of the training program for the mice welfare are discussed. We conclude that our training program was effective and that male mice can be successfully employed in space biomedical research.


Assuntos
Voo Espacial , Adaptação Fisiológica , Animais , Pesquisa Biomédica , Ingestão de Alimentos , Abrigo para Animais , Masculino , Camundongos Endogâmicos C57BL , Condicionamento Físico Animal , Projetos de Pesquisa , Federação Russa , Ausência de Peso
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