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1.
Cells ; 13(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38891027

RESUMEN

Sleep disruption is a frequent problem of advancing age, often accompanied by low-grade chronic central and peripheral inflammation. We examined whether chronic neuroinflammation in the preoptic and basal forebrain area (POA-BF), a critical sleep-wake regulatory structure, contributes to this disruption. We developed a targeted viral vector designed to overexpress tumor necrosis factor-alpha (TNFα), specifically in astrocytes (AAV5-GFAP-TNFα-mCherry), and injected it into the POA of young mice to induce heightened neuroinflammation within the POA-BF. Compared to the control (treated with AAV5-GFAP-mCherry), mice with astrocytic TNFα overproduction within the POA-BF exhibited signs of increased microglia activation, indicating a heightened local inflammatory milieu. These mice also exhibited aging-like changes in sleep-wake organization and physical performance, including (a) impaired sleep-wake functions characterized by disruptions in sleep and waking during light and dark phases, respectively, and a reduced ability to compensate for sleep loss; (b) dysfunctional VLPO sleep-active neurons, indicated by fewer neurons expressing c-fos after suvorexant-induced sleep; and (c) compromised physical performance as demonstrated by a decline in grip strength. These findings suggest that inflammation-induced dysfunction of sleep- and wake-regulatory mechanisms within the POA-BF may be a critical component of sleep-wake disturbances in aging.


Asunto(s)
Envejecimiento , Astrocitos , Prosencéfalo Basal , Área Preóptica , Sueño , Factor de Necrosis Tumoral alfa , Animales , Astrocitos/metabolismo , Astrocitos/patología , Envejecimiento/metabolismo , Área Preóptica/metabolismo , Ratones , Factor de Necrosis Tumoral alfa/metabolismo , Sueño/fisiología , Prosencéfalo Basal/metabolismo , Prosencéfalo Basal/patología , Vigilia , Masculino , Ratones Endogámicos C57BL , Neuronas/metabolismo , Neuronas/patología , Trastornos del Sueño-Vigilia/metabolismo , Trastornos del Sueño-Vigilia/patología
2.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38675474

RESUMEN

Nanodiamonds (NDs) are emerging as a novel nanoparticle class with growing interest in medical applications. The surface coating of NDs can be modified by attaching binding ligands or imaging probes, turning them into multi-modal targeting agents. In this investigation, we assessed the targeting efficacy of octreotide-functionalized 68Ga-radiolabelled NDs for cancer imaging and compared it with the tumor uptake using [68Ga]Ga-DOTA-TOC. In vivo studies in mice bearing AR42J tumors demonstrated the highest accumulation of the radiolabeled functionalized NDs in the liver and spleen, with relatively low tumor uptake compared to [68Ga]Ga-DOTA-TOC. Our findings suggest that, within the scope of this study, functionalization did not enhance the tumor-targeting capabilities of NDs.

3.
J Biol Chem ; 299(9): 105084, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37495111

RESUMEN

Long-range membrane traffic is guided by microtubule-associated proteins and posttranslational modifications, which collectively comprise a traffic code. The regulatory principles of this code and how it orchestrates the motility of kinesin and dynein motors are largely unknown. Septins are a large family of GTP-binding proteins, which assemble into complexes that associate with microtubules. Using single-molecule in vitro motility assays, we tested how the microtubule-associated SEPT2/6/7, SEPT2/6/7/9, and SEPT5/7/11 complexes affect the motilities of the constitutively active kinesins KIF5C and KIF1A and the dynein-dynactin-bicaudal D (DDB) motor complex. We found that microtubule-associated SEPT2/6/7 is a potent inhibitor of DDB and KIF5C, preventing mainly their association with microtubules. SEPT2/6/7 also inhibits KIF1A by obstructing stepping along microtubules. On SEPT2/6/7/9-coated microtubules, KIF1A inhibition is dampened by SEPT9, which alone enhances KIF1A, showing that individual septin subunits determine the regulatory properties of septin complexes. Strikingly, SEPT5/7/11 differs from SEPT2/6/7, in permitting the motility of KIF1A and immobilizing DDB to the microtubule lattice. In hippocampal neurons, filamentous SEPT5 colocalizes with somatodendritic microtubules that underlie Golgi membranes and lack SEPT6. Depletion of SEPT5 disrupts Golgi morphology and polarization of Golgi ribbons into the shaft of somato-proximal dendrites, which is consistent with the tethering of DDB to microtubules by SEPT5/7/11. Collectively, these results suggest that microtubule-associated complexes have differential specificities in the regulation of the motility and positioning of microtubule motors. We posit that septins are an integral part of the microtubule-based code that spatially controls membrane traffic.


Asunto(s)
Dineínas , Cinesinas , Proteínas Asociadas a Microtúbulos , Septinas , Dineínas/metabolismo , Cinesinas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Septinas/metabolismo , Células COS , Células HEK293 , Humanos , Animales , Chlorocebus aethiops , Transporte de Proteínas
4.
Int J Mol Sci ; 24(9)2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37176016

RESUMEN

The ventrolateral preoptic area (VLPO) contains GABAergic sleep-active neurons. However, the extent to which these neurons are involved in expressing spontaneous sleep and homeostatic sleep regulatory demands is not fully understood. We used calcium (Ca2+) imaging to characterize the activity dynamics of VLPO neurons, especially those expressing the vesicular GABA transporter (VGAT) across spontaneous sleep-waking and in response to homeostatic sleep demands. The VLPOs of wild-type and VGAT-Cre mice were transfected with GCaMP6, and the Ca2+ fluorescence of unidentified (UNID) and VGAT cells was recorded during spontaneous sleep-waking and 3 h of sleep deprivation (SD) followed by 1 h of recovery sleep. Although both VGAT and UNID neurons exhibited heterogeneous Ca2+ fluorescence across sleep-waking, the majority of VLPO neurons displayed increased activity during nonREM/REM (VGAT, 120/303; UNID, 39/106) and REM sleep (VGAT, 32/303; UNID, 19/106). Compared to the baseline waking, VLPO sleep-active neurons (n = 91) exhibited higher activity with increasing SD that remained elevated during the recovery period. These neurons also exhibited increased Ca2+ fluorescence during nonREM sleep, marked by increased slow-wave activity and REM sleep during recovery after SD. These findings support the notion that VLPO sleep-active neurons, including GABAergic neurons, are components of neuronal circuitry that mediate spontaneous sleep and homeostatic responses to sustained wakefulness.


Asunto(s)
Calcio , Sueño , Ratones , Animales , Sueño/fisiología , Neuronas GABAérgicas/fisiología , Privación de Sueño , Sueño REM , Área Preóptica , Calcio de la Dieta
5.
Mol Cell Biochem ; 478(10): 2141-2171, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36637616

RESUMEN

A trace element, known as a minor element, is a chemical element whose concentration is very low. They are divided into essential and non-essential classes. Numerous physiological and metabolic processes in both plants and animals require essential trace elements. These essential trace elements are so directly related to the metabolic and physiologic processes of the organism that either their excess or deficiency can result in severe bodily malfunction or, in the worst situations, death. Elements can be found in nature in various forms and are essential for the body to carry out its varied functions. Trace elements are crucial for biological, chemical, and molecular cell activity. Nutritional deficits can lead to weakened immunity, increased susceptibility to oral and systemic infections, delayed physical and mental development, and lower productivity. Trace element enzymes are involved in many biological and chemical processes. These compounds act as co-factors for a number of enzymes and serve as centers for stabilizing the structures of proteins and enzymes, allowing them to mediate crucial biological processes. Some trace elements control vital biological processes by attaching to molecules on the cell membrane's receptor site or altering the structure of the membrane to prevent specific molecules from entering the cell. Some trace elements are engaged in redox reactions. Trace elements have two purposes. They are required for the regular stability of cellular structures, but when lacking, they might activate alternate routes and induce disorders. Therefore, thoroughly understanding these trace elements is essential for maintaining optimal health and preventing disease.


Asunto(s)
Oligoelementos , Animales , Humanos
6.
Nucl Med Biol ; 116-117: 108310, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36565646

RESUMEN

PURPOSE: Nanodiamonds (NDs) represent a new class of nanoparticles and have gained increasing interest in medical applications. Modifying the surface coating by attaching binding ligands or imaging probes can transform NDs into multi-modal targeting probes. This study evaluated the biokinetics and biodistribution of 68Ga-radiolabelled NDs in a xenograft model. PROCEDURES: NDs were coated with an albumin-derived copolymer modified with desferrioxamine to provide a chelator for radiolabeling. In vivo studies were conducted in AR42J tumor-bearing CD1 mice to evaluate biodistribution and tumor accumulation of the NDs. RESULTS: Coated NDs were successfully radiolabeled using 68Ga at room temperature with radiolabeling efficiencies up to 91.8 ± 3.2 % as assessed by radio-TLC. In vivo studies revealed the highest accumulation in the liver and spleen, whereas tumor radioactivity concentration was low. CONCLUSIONS: Radiolabeling of coated NDs could be achieved. However, the obtained results indicate these coated NDs' limitations in their biodistribution within the conducted studies.


Asunto(s)
Nanodiamantes , Neoplasias , Humanos , Ratones , Animales , Radioisótopos de Galio , Distribución Tisular , Polímeros
7.
Proc Natl Acad Sci U S A ; 119(50): e2202803119, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36475946

RESUMEN

Cellular morphogenesis and processes such as cell division and migration require the coordination of the microtubule and actin cytoskeletons. Microtubule-actin crosstalk is poorly understood and largely regarded as the capture and regulation of microtubules by actin. Septins are filamentous guanosine-5'-triphosphate (GTP) binding proteins, which comprise the fourth component of the cytoskeleton along microtubules, actin, and intermediate filaments. Here, we report that septins mediate microtubule-actin crosstalk by coupling actin polymerization to microtubule lattices. Superresolution and platinum replica electron microscopy (PREM) show that septins localize to overlapping microtubules and actin filaments in the growth cones of neurons and non-neuronal cells. We demonstrate that recombinant septin complexes directly crosslink microtubules and actin filaments into hybrid bundles. In vitro reconstitution assays reveal that microtubule-bound septins capture and align stable actin filaments with microtubules. Strikingly, septins enable the capture and polymerization of growing actin filaments on microtubule lattices. In neuronal growth cones, septins are required for the maintenance of the peripheral actin network that fans out from microtubules. These findings show that septins directly mediate microtubule interactions with actin filaments, and reveal a mechanism of microtubule-templated actin growth with broader significance for the self-organization of the cytoskeleton and cellular morphogenesis.


Asunto(s)
Actinas , Septinas , Microtúbulos
8.
Nanomaterials (Basel) ; 12(24)2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36558325

RESUMEN

Nanodiamonds (NDs) have high potential as a drug carrier and in combination with nitrogen vacancies (NV centers) for highly sensitive MR-imaging after hyperpolarization. However, little remains known about their physiological properties in vivo. PET imaging allows further evaluation due to its quantitative properties and high sensitivity. Thus, we aimed to create a preclinical platform for PET and MR evaluation of surface-modified NDs by radiolabeling with both short- and long-lived radiotracers. Serum albumin coated NDs, functionalized with PEG groups and the chelator deferoxamine, were labeled either with zirconium-89 or gallium-68. Their biodistribution was assessed in two different mouse strains. PET scans were performed at various time points up to 7 d after i.v. injection. Anatomical correlation was provided by additional MRI in a subset of animals. PET results were validated by ex vivo quantification of the excised organs using a gamma counter. Radiolabeled NDs accumulated rapidly in the liver and spleen with a slight increase over time, while rapid washout from the blood pool was observed. Significant differences between the investigated radionuclides were only observed for the spleen (1 h). In summary, we successfully created a preclinical PET and MR imaging platform for the evaluation of the biodistribution of NDs over different time scales.

9.
Cells ; 11(14)2022 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-35883583

RESUMEN

The ventrolateral preoptic area (VLPO) predominantly contains sleep-active neurons and is involved in sleep regulation. The perifornical-hypothalamic area (PF-HA) is a wake-regulatory region and predominantly contains wake-active neurons. VLPO GABAergic/galaninergic neurons project to the PF-HA. Previously, the specific contribution of VLPO neurons projecting to the PF-HA (VLPO > PF-HAPRJ) in sleep regulation in rats could not be investigated due to the lack of tools that could selectively target these neurons. We determined the contribution of VLPO > PF-HAPRJ neurons in sleep regulation by selectively activating them using designer receptors exclusively activated by designer drugs (DREADDs) in wild-type Fischer-344 rats. We used a combination of two viral vectors to retrogradely deliver the Cre-recombinase gene, specifically, in VLPO > PF-HA neurons, and further express hM3Dq in those neurons to selectively activate them for delineating their specific contributions to sleep−wake functions. Compared to the control, in DREADD rats, clozapine-N-oxide (CNO) significantly increased fos-expression, a marker of neuronal activation, in VLPO > PF-HAPRJ neurons (2% vs. 20%, p < 0.01) during the dark phase. CNO treatment also increased nonREM sleep (27% vs. 40%, p < 0.01) during the first 3 h of the dark phase, when rats are typically awake, and after exposure to the novel environment (55% vs. 65%; p < 0.01), which induces acute arousal during the light phase. These results support a hypothesis that VLPO > PF-HAPRJ neurons constitute a critical component of the hypothalamic sleep−wake regulatory circuitry and promote sleep by suppressing wake-active PF-HA neurons.


Asunto(s)
Área Preóptica , Sueño , Neuronas GABAérgicas , Hipotálamo/fisiología , Área Preóptica/fisiología , Sueño/fisiología , Vigilia/fisiología
10.
Molecules ; 27(12)2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35744922

RESUMEN

Immunotherapy, which stimulates the body's immune system, has received a considerable amount of press in recent years because of its powerful benefits. Cancer immunotherapy has shown long-term results in patients with advanced disease that are not seen with traditional chemotherapy. Immune checkpoint inhibitors, cytokines like interleukin 2 (IL-2) and interferon-alpha (IFN), and the cancer vaccine sipuleucel-T have all been licensed and approved by the FDA for the treatment of various cancers. These immunotherapy treatments boost anticancer responses by stimulating the immune system. As a result, they have the potential to cause serious, even fatal, inflammatory and immune-related side effects in one or more organs. Immune checkpoint inhibitors (ICPIs) and chimeric antigen receptor (CAR) T-cell therapy are two immunotherapy treatments that are increasingly being used to treat cancer. Following their widespread usage in the clinic, a wave of immune-related adverse events (irAEs) impacting virtually every system has raised concerns about their unpredictability and randomness. Despite the fact that the majority of adverse effects are minimal and should be addressed with prudence, the risk of life-threatening complications exists. Although most adverse events are small and should be treated with caution, the risk of life-threatening toxicities should not be underestimated, especially given the subtle and unusual indications that make early detection even more difficult. Treatment for these issues is difficult and necessitates a multidisciplinary approach involving not only oncologists but also other internal medicine doctors to guarantee quick diagnosis and treatment. This study's purpose is to give a fundamental overview of immunotherapy and cancer-related side effect management strategies.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Inmunoterapia , Neoplasias , Vacunas contra el Cáncer/efectos adversos , Vacunas contra el Cáncer/uso terapéutico , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Factores Inmunológicos/efectos adversos , Factores Inmunológicos/uso terapéutico , Inmunoterapia/efectos adversos , Inmunoterapia/métodos , Inmunoterapia Adoptiva/efectos adversos , Neoplasias/tratamiento farmacológico
11.
Nano Lett ; 22(7): 2881-2888, 2022 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-35289621

RESUMEN

Nanodiamonds (NDs) with color centers are excellent emitters for various bioimaging and quantum biosensing applications. In our work, we explore new applications of NDs with silicon-vacancy centers (SiV) obtained by high-pressure high-temperature (HPHT) synthesis based on metal-catalyst-free growth. They are coated with a polypeptide biopolymer, which is essential for efficient cellular uptake. The unique optical properties of NDs with SiV are their high photostability and narrow emission in the near-infrared region. Our results demonstrate for the first time that NDs with SiV allow live-cell dual-color imaging and intracellular tracking. Also, intracellular thermometry and challenges associated with SiV atomic defects in NDs are investigated and discussed for the first time. NDs with SiV nanoemitters provide new avenues for live-cell bioimaging, diagnostic (SiV as a nanosized thermometer), and theranostic (nanodiamonds as drug carrier) applications.


Asunto(s)
Nanodiamantes , Termometría , Diagnóstico por Imagen , Portadores de Fármacos , Nanodiamantes/química , Silicio
12.
J Mater Chem B ; 9(28): 5621-5627, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34184014

RESUMEN

Long-term tracking of nanoparticles to resolve intracellular structures and motions is essential to elucidate fundamental parameters as well as transport processes within living cells. Fluorescent nanodiamond (ND) emitters provide cell compatibility and very high photostability. However, high stability, biocompatibility, and cellular uptake of these fluorescent NDs under physiological conditions are required for intracellular applications. Herein, highly stable NDs encapsulated with Cowpea chlorotic mottle virus capsid proteins (ND-CP) are prepared. A thin capsid protein layer is obtained around the NDs, which imparts reactive groups and high colloidal stability, while retaining the opto-magnetic properties of the coated NDs as well as the secondary structure of CPs adsorbed on the surface of NDs. In addition, the ND-CP shows excellent biocompatibility both in vitro and in vivo. Long-term 3D trajectories of the ND-CP with fine spatiotemporal resolutions are recorded; their intracellular motions are analyzed by different models, and the diffusion coefficients are calculated. The ND-CP with its brilliant optical properties and stability under physiological conditions provides us with a new tool to advance the understanding of cell biology, e.g., endocytosis, exocytosis, and active transport processes in living cells as well as intracellular dynamic parameters.


Asunto(s)
Materiales Biocompatibles/química , Bromovirus/química , Proteínas de la Cápside/análisis , Fluorescencia , Nanodiamantes/química , Proteínas de la Cápside/metabolismo , Cápsulas/química , Tamaño de la Partícula
13.
Nano Lett ; 21(9): 3780-3788, 2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-33881327

RESUMEN

Temperature is an essential parameter in all biological systems, but information about the actual temperature in living cells is limited. Especially, in photothermal therapy, local intracellular temperature changes induce cell death but the local temperature gradients are not known. Highly sensitive nanothermometers would be required to measure and report local temperature changes independent of the intracellular environment, including pH or ions. Fluorescent nanodiamonds (ND) enable temperature sensing at the nanoscale independent of external conditions. Herein, we prepare ND nanothermometers coated with a nanogel shell and the photothermal agent indocyanine green serves as a heat generator and sensor. Upon irradiation, programmed cell death was induced in cancer cells with high spatial control. In parallel, the increase in local temperature was recorded by the ND nanothermometers. This approach represents a great step forward to record local temperature changes in different cellular environments inside cells and correlate these with thermal biology.


Asunto(s)
Nanodiamantes , Calefacción , Calor , Medicina de Precisión , Temperatura
14.
Sleep ; 44(2)2021 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-33202015

RESUMEN

In the mammalian brain, adult neurogenesis has been extensively studied in the hippocampal sub-granular zone and the sub-ventricular zone of the anterolateral ventricles. However, growing evidence suggests that new cells are not only "born" constitutively in the adult hypothalamus, but many of these cells also differentiate into neurons and glia and serve specific functions. The preoptic-hypothalamic area plays a central role in the regulation of many critical functions, including sleep-wakefulness and circadian rhythms. While a role for adult hippocampal neurogenesis in regulating hippocampus-dependent functions, including cognition, has been extensively studied, adult hypothalamic neurogenic process and its contributions to various hypothalamic functions, including sleep-wake regulation are just beginning to unravel. This review is aimed at providing the current understanding of the hypothalamic adult neurogenic processes and the extent to which it affects hypothalamic functions, including sleep-wake regulation. We propose that hypothalamic neurogenic processes are vital for maintaining the proper functioning of the hypothalamic sleep-wake and circadian systems in the face of regulatory challenges. Sleep-wake disturbance is a frequent and challenging problem of aging and age-related neurodegenerative diseases. Aging is also associated with a decline in the neurogenic process. We discuss a hypothesis that a decrease in the hypothalamic neurogenic process underlies the aging of its sleep-wake and circadian systems and associated sleep-wake disturbance. We further discuss whether neuro-regenerative approaches, including pharmacological and non-pharmacological stimulation of endogenous neural stem and progenitor cells in hypothalamic neurogenic niches, can be used for mitigating sleep-wake and other hypothalamic dysfunctions in aging.


Asunto(s)
Hipotálamo , Neurogénesis , Envejecimiento , Animales , Sueño , Vigilia
15.
Neuroscience ; 427: 29-42, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-31846749

RESUMEN

Aging is a well-recognized risk factor for sleep disruption. The characteristics of sleep in aging include its disruption by frequent awakenings, a decline in both non-rapid eye movement (nonREM) and REM sleep amounts, and a weaker homeostatic response to sleep loss. Evidence also suggests that sleep in females is more sensitive to changes in the ovarian steroidal milieu. The Fischer-344 rats are commonly used experimental subjects in behavioral and physiological studies, including sleep and aging. Most sleep studies in Fischer-344 rats have used male subjects to avoid interactions between the estrus and sleep-waking cycles. The changes in the sleep-wake organization of female Fischer-344 rats, especially with advancing age, are not well-characterized. We determined sleep-waking features of cycling females across estrus stages. We also compared spontaneous and homeostatic sleep response profiles of young (3-4 months) and old (24-25 months) male and female Fischer-344 rats. The results suggest that: i) sleep-wake architectures across stages of estrus cycle in young females were largely comparable except for a significant suppression of REM sleep at proestrus night and an increase in REM sleep the following day; ii) despite hormonal differences, sleep-wake architecture in male and female rats of corresponding ages were comparable except for the suppression of REM sleep at proestrus night and higher nonREM delta power in recovery sleep; and iii) aging significantly affected sleep-wake amounts, sleep-wake stability, and homeostatic response to sleep loss in both male and female rats and that the adverse effects of aging were largely comparable in both sexes.


Asunto(s)
Ciclo Estral , Factores Sexuales , Sueño/fisiología , Envejecimiento , Animales , Femenino , Masculino , Ratas , Ratas Endogámicas F344 , Privación de Sueño/fisiopatología , Fases del Sueño/fisiología , Sueño REM/fisiología , Vigilia/fisiología
16.
Neuroscience ; 404: 541-556, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30738854

RESUMEN

Aging is associated with sleep-wake disruption, dampening of circadian amplitudes, and a reduced homeostatic sleep response. Aging is also associated with a decline in hypothalamic cell proliferation. We hypothesized that the aging-related decline in cell-proliferation contributes to the dysfunction of preoptic-hypothalamic sleep-wake and circadian systems and consequent sleep-wake disruption. We determined if cytosine-ß-D-arabinofuranoside (AraC), an antimitotic agent known to suppress hypothalamic cell proliferation and neurogenesis, causes sleep-wake instability in young mice. The sleep-wake profiles were compared during baseline, during 4 weeks of artificial cerebrospinal fluid (aCSF) + 5-bromo-2'-deoxyuridine (BrdU) or AraC+BrdU infusion into the lateral ventricle, and 8 weeks after treatments. The sleep-wake architecture after AraC treatment was further compared with sleep-wake profiles in aged mice. Compared to aCSF+BrdU, 4 weeks of AraC+BrdU infusion significantly decreased (-96%) the number of BrdU+ cells around the third ventricular wall and adjacent preoptic-hypothalamic area and produced a) sleep disruption during the light phase with decreases in non-rapid eye movement (nonREM) (-9%) and REM sleep (-21%) amounts, and increased numbers of shorter (<2 min; 142 versus 98 episodes/12 h) and decreased numbers of longer (>5 min; 19 versus 26 episodes/12 h) nonREM sleep episodes; and b) wake disruption during the dark phase, with increased numbers of shorter (138 versus 91 episodes/12 h) and decreased numbers of longer active waking (17 versus 24 episodes/12 h) episodes. AraC-treated mice also exhibited lower delta activity within nonREM recovery sleep. The sleep-wake architecture of AraC-treated mice was similar to that observed in aged mice. These findings are consistent with a hypothesis that a decrease in hypothalamic cell proliferation/neurogenesis is detrimental to sleep-wake and circadian systems and may underlie sleep-wake disturbance in aging.


Asunto(s)
Envejecimiento/fisiología , Proliferación Celular/fisiología , Hipotálamo/fisiología , Neurogénesis/fisiología , Sueño/fisiología , Vigilia/fisiología , Factores de Edad , Envejecimiento/efectos de los fármacos , Animales , Antimitóticos/administración & dosificación , Antimitóticos/toxicidad , Proliferación Celular/efectos de los fármacos , Ritmo Delta/efectos de los fármacos , Ritmo Delta/fisiología , Hipotálamo/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Neurogénesis/efectos de los fármacos , Sueño/efectos de los fármacos , Vigilia/efectos de los fármacos
17.
Sleep ; 41(10)2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29986116

RESUMEN

Growing evidence supports a role for the medullary parafacial zone in non-rapid eye movement (non-REM) sleep regulation. Cell-body specific lesions of the parafacial zone or disruption of its GABAergic/glycinergic transmission causes suppression of non-REM sleep, whereas, targeted activation of parafacial GABAergic/glycinergic neurons reduce sleep latency and increase non-REM sleep amount, bout duration, and cortical electroencephalogram (EEG) slow-wave activity. Parafacial GABAergic/glycinergic neurons also express sleep-associated c-fos immunoreactivity. Currently, it is not clear if parafacial neurons are non-REM sleep-active and/or REM sleep-active or play a role in the initiation or maintenance of non-REM sleep. We recorded extracellular discharge activity of parafacial neurons across the spontaneous sleep-waking cycle using microwire technique in freely behaving rats. Waking-, non-REM sleep-, and REM sleep-active neuronal groups were segregated by the ratios of their discharge rate changes during non-REM and REM sleep versus waking and non-REM sleep versus REM sleep. Parafacial neurons exhibited heterogeneity in sleep-waking discharge patterns, but 34 of 86 (40%) recorded neurons exhibited increased discharge rate during non-REM sleep compared to waking. These neurons also exhibited increased discharge prior to non-REM sleep onset, similar to median preoptic nucleus (MnPO) and ventrolateral preoptic area (VLPO) sleep-active neurons. However, unlike MnPO and VLPO sleep-active neurons, parafacial neurons were weakly-moderately sleep-active and exhibited a stable rather than decreasing discharge across sustained non-REM sleep episode. We show for the first time that the medullary parafacial zone contains non-REM sleep-active neurons. These neurons are likely functionally important brainstem compliments to the preoptic-hypothalamic sleep-promoting neuronal networks that underlie sleep onset and maintenance.


Asunto(s)
Neuronas GABAérgicas/fisiología , Bulbo Raquídeo/fisiología , Área Preóptica/fisiología , Sueño REM/fisiología , Animales , Electroencefalografía , Masculino , Bulbo Raquídeo/citología , Área Preóptica/citología , Ratas , Ratas Sprague-Dawley , Sueño/fisiología , Vigilia/fisiología
18.
J Neurochem ; 142(5): 620-623, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28736837

RESUMEN

Alcohol causes adenosine buildup, which inhibits wake-active neurons via adenosine A1 receptors thus disinhibiting sleep active neurons and also stimulates sleep-active neurons via A2A receptors, causing sleep. This editorial highlights the study entitled, "Lesions of the basal forebrain cholinergic neurons attenuates sleepiness and adenosine after alcohol consumption" by Sharma and colleagues. They report that the wake-promoting basal forebrain (BF) cholinergic neurons play a crucial role in mediating acute alcohol-induced sleep via adenosinergic signaling.


Asunto(s)
Adenosina/metabolismo , Consumo de Bebidas Alcohólicas/metabolismo , Prosencéfalo Basal/fisiología , Neuronas Colinérgicas/fisiología , Homeostasis/fisiología , Sueño/fisiología , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/tendencias , Animales , Prosencéfalo Basal/efectos de los fármacos , Neuronas Colinérgicas/efectos de los fármacos , Homeostasis/efectos de los fármacos , Humanos , Receptor de Adenosina A1/fisiología , Receptores de Adenosina A2/fisiología , Sueño/efectos de los fármacos , Vigilia/efectos de los fármacos , Vigilia/fisiología
19.
Curr Opin Neurobiol ; 44: 228-235, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28628804

RESUMEN

Sleep homeostasis is a fundamental property of vigilance state regulation that is highly conserved across species. Neuronal systems and circuits that underlie sleep homeostasis are not well understood. In Drosophila, a neuronal circuit involving neurons in the ellipsoid body and in the dorsal Fan-shaped body is a candidate for both tracing sleep need during waking and translating it to increased sleep drive and expression. Sleep homeostasis in rats and mice involves multiple neuromodulators acting on multiple wake- and sleep-promoting neuronal systems. A functional central homeostat emerges from A1 receptor mediated actions of adenosine on wake-promoting neurons in the basal forebrain and hypothalamus, and A2A adenosine receptor-mediated actions on sleep-promoting neurons in the preoptic hypothalamus and nucleus accumbens.


Asunto(s)
Homeostasis/fisiología , Neuronas/fisiología , Sueño/fisiología , Adenosina/metabolismo , Animales , Vigilia/fisiología
20.
Sleep ; 37(5): 1011-20, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24790280

RESUMEN

STUDY OBJECTIVES: The hypocretins (HCRTs) are two hypothalamic peptides predominantly localized to neurons in the perifornical, dorsomedial, and lateral hypothalamic area (PF-LHA). Evidence suggests that HCRT signaling is critical for the promotion and stabilization of active-arousal and its loss or malfunction leads to symptoms of narcolepsy. In the PF-LHA, HCRT neurons are intermingled with glutamate-expressing neurons and also co-express glutamate. Evidence suggests that HCRT-glutamate interactions within the PF-LHA may play a critical role in maintaining behavioral arousal. However, the relative contributions of the glutamate and HCRT in sleep-wake regulation are not known. DESIGN: We determined whether a lack of HCRT signaling in the prepro-orexin-knockout (HCRT-KO) mouse attenuates/compromises the wake-promoting ability of glutamatergic activation of the PF-LHA region. We used reverse microdialysis to deliver N-methyl-D-aspartate (NMDA) into the HCRT zone of the PF-LHA in HCRT-KO and wild-type (WT) mice to evaluate the contributions of glutamatergic vs. HCRT signaling in sleep-wake regulation. MEASUREMENTS AND RESULTS: As compared to respective controls, local perfusion of NMDA into the PF-LHA, dose-dependently increased active-waking with concomitant reductions in nonREM and REM sleep in spontaneously sleeping WT as well as HCRT-KO mice. However, compared to WT, the NMDA-induced behavioral changes in HCRT-KO mice were significantly attenuated, as evidenced by the higher dose of NMDA needed and lower magnitude of changes induced in sleep-wake parameters. Although not observed in WT mice, the number of cataplectic events increased significantly during NMDA-induced behavioral arousal in HCRT-KO mice. CONCLUSIONS: The findings of this study are consistent with a hypothesis that synergistic interactions between hypocretin and glutamatergic mechanisms within the perifornical, dorsomedial, and lateral hypothalamic area are critical for maintaining behavioral arousal, especially arousal involving elevated muscle tone.


Asunto(s)
Ácido Glutámico/metabolismo , Área Hipotalámica Lateral/fisiología , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Neuropéptidos/deficiencia , Animales , Nivel de Alerta/efectos de los fármacos , Nivel de Alerta/fisiología , Área Hipotalámica Lateral/citología , Área Hipotalámica Lateral/efectos de los fármacos , Masculino , Ratones , Ratones Noqueados , N-Metilaspartato/metabolismo , N-Metilaspartato/farmacología , Narcolepsia , Neuronas/fisiología , Orexinas , Sueño/fisiología , Vigilia/efectos de los fármacos
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