Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Vasyl Sava is active.

Publication


Featured researches published by Vasyl Sava.


Journal of Alzheimer's Disease | 2010

Electromagnetic Field Treatment Protects Against and Reverses Cognitive Impairment in Alzheimer's Disease Mice

Gary W. Arendash; Juan Sanchez-Ramos; Takashi Mori; Malgorzata Mamcarz; Xiaoyang Lin; Melissa Runfeldt; Li Wang; Guixin Zhang; Vasyl Sava; Jun Tan; Chuanhai Cao

Despite numerous studies, there is no definitive evidence that high-frequency electromagnetic field (EMF) exposure is a risk to human health. To the contrary, this report presents the first evidence that long-term EMF exposure directly associated with cell phone use (918 MHz; 0.25 w/kg) provides cognitive benefits. Both cognitive-protective and cognitive-enhancing effects of EMF exposure were discovered for both normal mice and transgenic mice destined to develop Alzheimers-like cognitive impairment. The cognitive interference task utilized in this study was designed from, and measure-for-measure analogous to, a human cognitive interference task. In Alzheimers disease mice, long-term EMF exposure reduced brain amyloid-beta (Abeta) deposition through Abeta anti-aggregation actions and increased brain temperature during exposure periods. Several inter-related mechanisms of EMF action are proposed, including increased Abeta clearance from the brains of Alzheimers disease mice, increased neuronal activity, and increased cerebral blood flow. Although caution should be taken in extrapolating these mouse studies to humans, we conclude that EMF exposure may represent a non-invasive, non-pharmacologic therapeutic against Alzheimers disease and an effective memory-enhancing approach in general.


Neuroscience | 2009

Granulocyte colony stimulating factor decreases brain amyloid burden and reverses cognitive impairment in Alzheimer's mice.

Juan Sanchez-Ramos; S. Song; Vasyl Sava; Briony J. Catlow; Xiaoyang Lin; Takashi Mori; Chuanhai Cao; Gary W. Arendash

Granulocyte colony stimulating factor (G-CSF) is a multi-modal hematopoietic growth factor, which also has profound effects on the diseased CNS. G-CSF has been shown to enhance recovery from neurologic deficits in rodent models of ischemia. G-CSF appears to facilitate neuroplastic changes by both mobilization of bone marrow-derived cells and by its direct actions on CNS cells. The overall objective of the study was to determine if G-CSF administration in a mouse model of Alzheimers disease (AD) (Tg APP/PS1) would impact hippocampal-dependent learning by modifying the underlying disease pathology. A course of s.c. administration of G-CSF for a period of less than three weeks significantly improved cognitive performance, decreased beta-amyloid deposition in hippocampus and entorhinal cortex and augmented total microglial activity. Additionally, G-CSF reduced systemic inflammation indicated by suppression of the production or activity of major pro-inflammatory cytokines in plasma. Improved cognition in AD mice was associated with increased synaptophysin immunostaining in hippocampal CA1 and CA3 regions and augmented neurogenesis, evidenced by increased numbers of calretinin-expressing cells in dentate gyrus. Given that G-CSF is already utilized clinically to safely stimulate hematopoietic stem cell production, these basic research findings will be readily translated into clinical trials to reverse or forestall the progression of dementia in AD. The primary objective of the present study was to determine whether a short course of G-CSF administration would have an impact on the pathological hallmark of AD, the age-dependent accumulation of A beta deposits, in a transgenic mouse model of AD (APP+ PS1; Tg). A second objective was to determine whether such treatment would impact cognitive performance in a hippocampal-dependent memory paradigm. To explain the G-CSF triggered amyloid reduction and associated reversal of cognitive impairment, several mechanisms of action were explored. (1) G-CSF was hypothesized to increase activation of resident microglia and to increase mobilization of marrow-derived microglia. The effect of G-CSF on microglial activation was examined by quantitative measurements of total microglial burden. To determine if G-CSF increased trafficking of marrow-derived microglia into brain, bone marrow-derived green fluorescent protein-expressing (GFP+) microglia were visualized in the brains of chimeric AD mice. (2) To assess the role of immune-modulation in mediating G-CSF effects, a panel of cytokines was measured in both plasma and brain. (3) To test the hypothesis that reduction of A beta deposits can affect synaptic area, quantitative measurement of synaptophysin immunoreactivity in hippocampal CA1 and CA3 sectors was undertaken. (4) To learn whether enhanced hippocampal neurogenesis was induced by G-CSF treatment, numbers of calretinin-expressing cells were determined in dentate gyrus.


Molecular Pharmaceutics | 2012

Improving solubility and pharmacokinetics of meloxicam via multiple-component crystal formation.

David R. Weyna; Miranda L. Cheney; Ning Shan; Mazen Hanna; Michael J. Zaworotko; Vasyl Sava; Shijie Song; Juan Sanchez-Ramos

Meloxicam is a nonsteroidal anti-inflammatory drug prescribed for rheumatoid arthritis, osteoarthritis, postoperative pain and fever. Meloxicam exhibits low solubility in acidic aqueous media and a slow onset of action in biological subjects. An oral dosage form of meloxicam with enhanced aqueous solubility is desired to enable a faster onset of action and its use for mild-to-medium-level acute pain relief. With this in mind, we examine the solubility and pharmacokinetics of 12 meloxicam cocrystals with carboxylic acids. Dissolution studies of meloxicam and its cocrystals were performed in pH 6.5 phosphate buffer solutions at 37 °C. In addition, pharmacokinetic profiles over four hours were acquired after oral administration of a 10 mg/kg (meloxicam equivalent) solid suspension in rats. The majority of meloxicam cocrystals were found to achieve higher meloxicam concentrations in dissolution media and enhanced oral absorption compared to that of pure meloxicam. All meloxicam cocrystals were converted to meloxicam form I when the slurry reached equilibrium. To better understand how cocrystallization impacts the absorption of meloxicam after oral administration, correlations between the in vitro and in vivo data were explored. The results suggest that the meloxicam cocrystals with a faster dissolution rate would exhibit increased oral absorption and an earlier onset of action.


European Journal of Pharmacology | 2010

Effects of MDMA (“ecstasy”) during adolescence on place conditioning and hippocampal neurogenesis

Briony J. Catlow; Kimberly A. Badanich; Ashley E. Sponaugle; Amanda Rowe; Shijie Song; Igor Rafalovich; Vasyl Sava; Cheryl L. Kirstein; Juan Sanchez-Ramos

The use of 3,4,methylenedioxymethamphetamine (MDMA), the active agent in ecstasy, during adolescence is widespread yet the effects on adolescent behavior and brain development are unknown. The aim of the present study was 1) to evaluate effects of MDMA in adolescent rats using the conditioned place preference (CPP) paradigm to measure MDMA-induced reward and 2) assess effects of MDMA administration on cellular proliferation, survival and neurogenesis in the dentate gyrus of the hippocampus. During the adolescent period, MDMA CPP was measured in adolescents [postnatal day (PND) 28-39] by training rats to associate 1.25, 2.5, 5.0mg/kg MDMA or saline administration with environmental cues. After CPP ended, bromodeoxyuridine (BrdU) was injected and rats were euthanized either 24h (to evaluate cell proliferation) or 2 weeks (to assess neurogenesis) after the last MDMA injection. Adolescents expressed a CPP for 2.5mg/kg MDMA. Repeated exposure to 5.0mg/kg MDMA during adolescence increased cell proliferation, yet diminished neurogenesis, an effect that was replicated using flow cytometry. These findings suggest differential dose effects of adolescent MDMA exposure on reward related behaviors and hippocampal neurogenesis.


Journal of the Neurological Sciences | 2006

Can low level exposure to ochratoxin-A cause parkinsonism?

Vasyl Sava; O. Reunova; A. Velasquez; Juan Sanchez-Ramos

Mycotoxins are fungal metabolites with pharmacological activities that have been utilized in the production of antibiotics, growth promoters, and other classes of drugs. Some mycotoxins have been developed as biological and chemical warfare agents. Bombs and ballistic missiles loaded with aflatoxin were stockpiled and may have been deployed by Iraq during the first Gulf War. In light of the excess incidence of amyotrophic lateral sclerosis (ALS) in veterans from Operation Desert Storm, the potential for delayed neurotoxic effects of low doses of mycotoxins should not be overlooked. Ochratoxin-A (OTA) is a common mycotoxin with complex mechanisms of action, similar to that of the aflatoxins. Acute administration of OTA at non-lethal doses (10% of the LD(50)) have been shown to increase oxidative DNA damage in brain up to 72 h, with peak effects noted at 24 h in midbrain (MB), caudate/putamen (CP) and hippocampus (HP). Levels of dopamine (DA) and its metabolites in the striatum (e.g., CP) were shown to be decreased in a dose-dependent manner. The present study focused on the effects of chronic low dose OTA exposure on regional brain oxidative stress and striatal DA metabolism. Continuous administration of low doses of OTA with implanted subcutaneous Alzet minipumps caused a small but significant decrease in striatal DA levels and an upregulation of anti-oxidative systems and DNA repair. It is possible that low dose exposure to OTA will result in an earlier onset of parkinsonism when normal age-dependent decline in striatal DA levels are superimposed on the mycotoxin-induced lesion.


Neuroscience Letters | 2011

Granulocyte-colony stimulating factor (G-CSF) enhances recovery in mouse model of Parkinson's disease.

Shijie Song; Vasyl Sava; Amanda Rowe; Kunyu Li; Chuanhai Cao; Takashi Mori; Juan Sanchez-Ramos

INTRODUCTION Granulocyte-colony stimulating factor (G-CSF) is used routinely in clinical practice for the treatment of neutropenia and to increase generation of hematopoietic stem cells in bone marrow donors. A growing body of literature on the neurotrophic effects of G-CSF has led to clinical trials in stroke, Alzheimers disease (AD) and Parkinsons disease (PD). OBJECTIVES The primary objective of this study was to determine if G-CSF administration would rescue the nigro-striatal system and restore locomotor function after completion of a sub-acute course of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) administration (30mg/kg i.p. for 5 days) in 12 month-old mice. A secondary aim was to determine if G-CSF affects the neuro-inflammatory response by modulating microglial activation in striatum and midbrain. RESULTS MPTP-treated mice were impaired on the rotometer test after the last dose of the toxicant and remained impaired until euthanasia. MPTP-treated mice that were given an 8-day regimen of G-CSF starting 2 days after the last dose of toxicant enhanced motor performance compared to the MPTP alone group. MPTP treatment depleted striatal DA (DA) levels; G-CSF given after MPTP resulted in a partial, significant repletion of DA levels. Total microglial burden in the striatum was increased significantly in MPTP-treated mice and was reduced after G-CSF rescue. CONCLUSION G-CSF enhances recovery of DA nigro-striatal function from MPTP toxicity in part by modulating the microglial response to injury. The G-CSF receptor may provide a novel target for modifying the disease process in Parkinsons disease.


Journal of Neuroscience Research | 2016

Granulocyte colony‐stimulating factor promotes behavioral recovery in a mouse model of traumatic brain injury

Shijie Song; Xiaoyuan Kong; Sandra Acosta; Vasyl Sava; Cesar V. Borlongan; Juan Sanchez-Ramos

Hematopoietic growth factors such as granulocyte colony‐stimulating factor (G‐CSF) represent a novel approach for treatment of traumatic brain injury (TBI). After mild controlled cortical impact (CCI), mice were treated with G‐CSF (100 μg/kg) for 3 consecutive days. The primary behavioral endpoint was performance on the radial arm water maze (RAWM), assessed 7 and 14 days after CCI. Secondary endpoints included 1) motor performance on a rotating cylinder (rotarod), 2) measurement of microglial and astroglial response, 3) hippocampal neurogenesis, and 4) measures of neurotrophic factors (brain‐derived neurotrophic factor [BDNF] and glial cell line‐derived neurotrophic factor [GDNF]) and cytokines in brain homogenates. G‐CSF‐treated animals performed significantly better than vehicle‐treated mice in the RAWM at 1 and 2 weeks but not on the rotarod. Cellular changes found in the G‐CSF group included increased hippocampal neurogenesis as well as astrocytosis and microgliosis in both the striatum and the hippocampus. Neurotrophic factors GDNF and BDNF, elaborated by activated microglia and astrocytes, were increased in G‐CSF‐treated mice. These factors along with G‐CSF itself are known to promote hippocampal neurogenesis and inhibit apoptosis and likely contributed to improvement in the hippocampal‐dependent learning task. Six cytokines that were modulated by G‐CSF treatment following CCI were elevated on day 3, but only one of them remained altered by day 7, and all of them were no different from vehicle controls by day 14. The pro‐ and anti‐inflammatory cytokines modulated by G‐CSF administration interact in a complex and incompletely understood network involving both damage and recovery processes, underscoring the dual role of inflammation after TBI.


Stem Cells International | 2013

Hippocampal Neurogenesis and the Brain Repair Response to Brief Stereotaxic Insertion of a Microneedle

Shijie Song; S. Song; Chuanhai Cao; Xiaoyang Lin; Kunyu Li; Vasyl Sava; Juan Sanchez-Ramos

We tested the hypothesis that transient microinjury to the brain elicits cellular and humoral responses that stimulate hippocampal neurogenesis. Brief stereotaxic insertion and removal of a microneedle into the right hippocampus resulted in (a) significantly increased expression of granulocyte-colony stimulating factor (G-CSF), the chemokine MIP-1a, and the proinflammatory cytokine IL12p40; (b) pronounced activation of microglia and astrocytes; and (c) increase in hippocampal neurogenesis. This study describes immediate and early humoral and cellular mechanisms of the brains response to microinjury that will be useful for the investigation of potential neuroprotective and deleterious effects of deep brain stimulation in various neuropsychiatric disorders.


Journal of Alzheimers Disease & Parkinsonism | 2013

Direct Actions of Granulocyte-Colony Stimulating Factor on Human Neuronal and Monocytic Cell Lines

a Pennington; Vasyl Sava; Shijie Song; Niketa A. Patel; Juan Sanchez-Ramos

Objective: The aim of the study was to elucidate cellular mechanism(s) of G-CSF action by direct application to neuronal and monocytic cell lines. Background: Granulocyte colony stimulating factor (G-CSF) administration produces beneficial effects in rodent models of stroke, trauma and neurodegenerative diseases by acting on both bone marrow-derived and neuronal cells. Methods: Cell culture models of monocytes (THP-1) and neurons (SH-SY5Y) cells were incubated with G-CSF. The following parameters were measured: G-CSF receptor binding kinetics; DNA synthesis; signal transduction, in particular expression of alternatively spliced protein kinase C (PKCδVIII) and the anti-apoptotic protein Bcl-2; changes in adhesiveness and migratory properties induced by G-CSF in the monocytic cells. Results: G-CSF receptor binding kinetics in the two lines differed, with Kd in the neuronal line being significantly higher than that of the monocytic cells. Despite higher affinity of G-CSF for receptors on the monocytic cells, G-CSF treatment increased Bcl- 2 expression in the neuronal line at lower concentrations than that required in the monocytic cell line. G-CSF did not increase either cellular adhesiveness or migration through a semi-permeable membrane, whereas monocyte chemotactic protein (MCP- 1) significantly improved migration. Conclusions: The cellular and molecular responses to G-CSF treatment of monocytic cells suggest that neither changes in adhesiveness nor migratory capacity are responsible for the beneficial effects of G-CSF administration in models of neurologic diseases. G-CSF induction of anti-apoptotic signaling in neurons is an important component of its neuroprotective effects in models of brain injury. Disclosure: Dr. Sava has nothing to disclose. Dr. Song has nothing to disclose. Dr. Patel has nothing to disclose. Dr. Sanchez-Ramos has received personal compensation for activities with Lundbeck and Teva Neuroscience.


Journal of Neuroscience Research | 2014

In vivo administration of granulocyte colony‐stimulating factor restores long‐term depression in hippocampal slices prepared from transgenic APP/PS1 mice

Shijie Song; Xinming Wang; Vasyl Sava; Edwin J. Weeber; Juan Sanchez-Ramos

Granulocyte colony‐stimulating factor (G‐CSF) is a hematopoietic cytokine that also possesses neurotrophic and antiapoptotic properties. G‐CSF has been reported to decrease amyloid burden significantly, promote hippocampal neurogenesis, and improve spatial learning in a mouse model of Alzheimers disease. To understand better the effects of G‐CSF on hippocampal‐dependent learning, the present study focused on electrophysiological correlates of neuroplasticity, long‐term potentiation (LTP), and long‐term depression (LTD). Two cohorts of transgenic APP/PS1 mice, with or without prior bone marrow transplantation from Tg GFP mice, were treated in vivo for 2 weeks with G‐CSF or vehicle. After completion of the treatments, hippocampal slices were prepared for electrophysiological studies of LTP and LTD. LTP was induced and maintained in both G‐CSF‐treated and vehicle‐treated groups of Tg APP/PS1. In contrast, LTD could not be induced in vehicle‐treated Tg APP/PS1 mice, but G‐CSF treatment restored LTD. The LTP and LTD results obtained from the cohort of bone marrow‐grafted Tg APP/PS1 mice did not differ from those from nongrafted Tg APP/PS1 mice. The mechanism by which G‐CSF restores LTD is not known, but it is possible that its capacity to reduce amyloid plaques results in increased soluble oligomers of amyloid‐β (A‐β), which in turn may facilitate LTD. This mechanism would be consistent with the recent report that soluble A‐β oligomers promote LTD in hippocampal slices.

Collaboration


Dive into the Vasyl Sava's collaboration.

Top Co-Authors

Avatar

Juan Sanchez-Ramos

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

Shijie Song

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

A. Velasquez

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

Chuanhai Cao

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

S. Song

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

O. Reunova

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

Shyam S. Mohapatra

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

Subhra Mohapatra

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

Xiaoyang Lin

University of South Florida

View shared research outputs
Top Co-Authors

Avatar

Xiaoyuan Kong

United States Department of Veterans Affairs

View shared research outputs
Researchain Logo
Decentralizing Knowledge