Inflammatory Diseases of the Brain

2020 ◽  
Author(s):  
Naoyuki Obokata ◽  
Chie Seki ◽  
Takeshi Hirata ◽  
Jun Maeda ◽  
Hideki Ishii ◽  
...  

AbstractPurposePhosphodiesterase (PDE) 7 is a potential therapeutic target for neurological and inflammatory diseases, although in-vivo visualization of PDE7 has not been successful. In this study, we aimed to develop [11C]MTP38 as a novel positron emission tomography (PET) ligand for PDE7.Methods[11C]MTP38 was radiosynthesized by 11C-cyanation of a bromo precursor with [11C]HCN. PET scans of rat and rhesus monkey brains and in-vitro autoradiography of brain sections derived from these species were conducted with [11C]MTP38. In monkeys, dynamic PET data were analyzed with an arterial input function to calculate the total distribution volume (VT). The non-displaceable binding potential (BPND) in the striatum was also determined by a reference tissue model with cerebellar reference. Finally, striatal occupancy of PDE7 by an inhibitor was calculated in monkeys according to changes in BPND.Results[11C]MTP38 was synthesized with radiochemical purity ≥ 99.4% and molar activity of 38.6 ± 12.6 GBq/μmol. Autoradiography revealed high radioactivity in the striatum and its reduction by non-radiolabeled ligands, in contrast with unaltered autoradiographic signals in other regions. In-vivo PET after radioligand injection to rats and monkeys demonstrated that radioactivity was rapidly distributed to the brain and intensely accumulated in the striatum relative to the cerebellum. Correspondingly, estimated VT values in the monkey striatum and cerebellum were 3.59 and 2.69 mL/cm3, respectively. The cerebellar VT value was unchanged by pretreatment with unlabeled MTP38. Striatal BPND was reduced in a dose-dependent manner after pretreatment with MTP-X, a PDE7 inhibitor. Relationships between PDE7 occupancy by MTP-X and plasma MTP-X concentration could be described by Hill’s sigmoidal function.ConclusionWe have provided the first successful preclinical demonstration of in-vivo PDE7 imaging with a specific PET radioligand. [11C]MTP38 is a feasible radioligand for evaluating PDE7 in the brain and is currently being applied to a first-in-human PET study.


2014 ◽  
Vol 4 (3) ◽  
pp. 192-198
Author(s):  
C. Takahashi ◽  
M. Mass ◽  
B. Hamilton ◽  
S. H. Guletkin ◽  
D. Bourdette

1978 ◽  
pp. 131-138 ◽  
Author(s):  
M. G. Dupont ◽  
L. L. Mortelmans ◽  
D. Baleriaux-Waha ◽  
A. Bollaert ◽  
L. Jeanmart

2015 ◽  
Vol 83 (9) ◽  
pp. 952-964 ◽  
Author(s):  
Sniya Valsa Sudhakar ◽  
Karthik Muthusamy ◽  
Sunithi Mani ◽  
Sridhar Gibikote ◽  
Manohar Shroff

1997 ◽  
Vol 3 (3) ◽  
pp. 184-190 ◽  
Author(s):  
P. Kivisäkk ◽  
GV Alm ◽  
WZ Tian ◽  
D. Matusevicius ◽  
S. Fredrikson ◽  
...  

Interferon-β-1b (IFN-β-1b) is an immunomodulatory therapy of multiple sclerosis (MS), reducing the numbers and severity of exacerbations and the total lesion load measured by magnetic resonance imaging of the brain. The benefits of IFN-β-1b could be hampered by the development of neutralising antibodies against the compound. Our results confirmed earlier studies, showing that 42% of MS patients treated with IFN-β-1b for more than 3 months had developed neutralising antibodies. The occurrence of binding anti-IFN-β-1b antibodies, presently not believed to impede the clinical efficacy of IFN-β-1b, were demonstrated by an immunoassay in some patients already after I month of treatment and in 78% after 3 months. The development of binding antibodies seemed to be an early phenomenon, preceding the appearance of neutralising antibodies. Antibodies crossreacting with IFN-β-1a and natural IFN-β were also found in a majority of IFN-β-1b treated patients with high titres of binding antibodies. Employing a solid-phase enzyme-linked immunospot (ELISPOT) assay, 68% of MS patients treated with IFN-β-1b for 1 -23 months had elevated numbers of anti-IFN-β-1b-antibody secreting cells in blood, compared to 18% of untreated MS patients and 20% among patients with other neurological diseases. Thus, our findings confirm that IFN-β-1 b is immunogenic in MS patients. High levels of anti-IFN-β-1b antibody secreting cells were, however, also found in two untreated control patients with inflammatory diseases, suggesting that anti-IFN-β-1b antibodies might also occur spontaneously.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Linan Liu ◽  
Mark A. Eckert ◽  
Hamidreza Riazifar ◽  
Dong-Ku Kang ◽  
Dritan Agalliu ◽  
...  

Systemically infused mesenchymal stem cells (MSCs) are emerging therapeutics for treating stroke, acute injuries, and inflammatory diseases of the central nervous system (CNS), as well as brain tumors due to their regenerative capacity and ability to secrete trophic, immune modulatory, or other engineered therapeutic factors. It is hypothesized that transplanted MSCs home to and engraft at ischemic and injured sites in the brain in order to exert their therapeutic effects. However, whether MSCs possess the ability to migrate across the blood-brain barrier (BBB) that separates the blood from the brain remains unresolved. This review analyzes recent advances in this area in an attempt to elucidate whether systemically infused MSCs are able to actively transmigrate across the CNS endothelium, particularly under conditions of injury or stroke. Understanding the fate of transplanted MSCs and their CNS trafficking mechanisms will facilitate the development of more effective stem-cell-based therapeutics and drug delivery systems to treat neurological diseases and brain tumors.


2014 ◽  
Vol 307 (10) ◽  
pp. E896-E905 ◽  
Author(s):  
Tammy M. Barnes ◽  
Yolanda F. Otero ◽  
Amicia D. Elliott ◽  
Alicia D. Locke ◽  
Carlo M. Malabanan ◽  
...  

Inappropriate glucagon secretion contributes to hyperglycemia in inflammatory disease. Previous work implicates the proinflammatory cytokine interleukin-6 (IL-6) in glucagon secretion. IL-6-KO mice have a blunted glucagon response to lipopolysaccharide (LPS) that is restored by intravenous replacement of IL-6. Given that IL-6 has previously been demonstrated to have a transcriptional (i.e., slow) effect on glucagon secretion from islets, we hypothesized that the rapid increase in glucagon following LPS occurred by a faster mechanism, such as by action within the brain. Using chronically catheterized conscious mice, we have demonstrated that central IL-6 stimulates glucagon secretion uniquely in the presence of an accompanying stressor (hypoglycemia or LPS). Contrary to our hypothesis, however, we found that IL-6 amplifies glucagon secretion in two ways; IL-6 not only stimulates glucagon secretion via the brain but also by direct action on islets. Interestingly, IL-6 augments glucagon secretion from both sites only in the presence of an accompanying stressor (such as epinephrine). Given that both adrenergic tone and plasma IL-6 are elevated in multiple inflammatory diseases, the interactions of the IL-6 and catecholaminergic signaling pathways in regulating GCG secretion may contribute to our present understanding of these diseases.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jerry Y. Niederkorn

The eye and the brain have limited capacities for regeneration and as such, immune-mediated inflammation can produce devastating consequences in the form of neurodegenerative diseases of the central nervous system or blindness as a result of ocular inflammatory diseases such as uveitis. Accordingly, both the eye and the brain are designed to limit immune responses and inflammation – a condition known as “immune privilege”. Immune privilege is sustained by physiological, anatomical, and regulatory processes that conspire to restrict both adaptive and innate immune responses.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Ferdinando Nicoletti ◽  
Ingrid Philippens ◽  
Paolo Fagone ◽  
Clarence N. Ahlem ◽  
Christopher L. Reading ◽  
...  

17α-Ethynyl-androst-5-ene-3β,7β,17β-triol (HE3286) is a synthetic androstenetriol in Phase II clinical development for the treatment of inflammatory diseases. HE3286 was evaluated for blood-brain barrier (BBB) permeability in mice, and efficacy in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) murine model of Parkinson’s disease (PD). We found that HE3286 freely penetrated the BBB. HE3286 treatment significantly improved motor function compared to vehicle in the rotarod test (mean 58.2 sec versus 90.9 sec,P<0.0001), and reduced inflammatory mediator gene expression in the brain (inducible nitric oxide synthase, 20%,P=0.002; tumor necrosis factorα, 40%,P=0.038, and interleukin-1β, 33%,P=0.02) measured by reverse-transcriptase polymerase chain reaction. Brain tissue histopathology and immunohistochemistry showed that HE3286 treatment increased the numbers of tyrosine hydroxylase-positive cells by 17% compared to vehicle (P=0.003), and decreased the numbers of damaged neurons by 38% relative to vehicle (P=0.029). L-3,4-dihydroxyphenylalanine (L-DOPA) efficacy was not enhanced by concurrent administration of HE3286. HE3286 administration prior to MPTP did not enhance efficacy. Our data suggest a potential role for HE3286 in PD treatment, and provides incentive for further investigation.


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