50 research outputs found
A Synthetic Agonist to Vasoactive Intestinal Peptide Receptor-2 Induces Regulatory T Cell Neuroprotective Activities in Models of Parkinson\u27s Disease
A paradigm shift has emerged in Parkinson\u27s disease (PD) highlighting the prominent role of CD4+ Tregs in pathogenesis and treatment. Bench to bedside research, conducted by others and our own laboratories, advanced a neuroprotective role for Tregs making pharmacologic transformation of immediate need. Herein, a vasoactive intestinal peptide receptor-2 (VIPR2) peptide agonist, LBT-3627, was developed as a neuroprotectant for PD-associated dopaminergic neurodegeneration. Employing both 6-hydroxydopamine (6-OHDA) and α-synuclein (α-Syn) overexpression models in rats, the sequential administration of LBT-3627 increased Treg activity without altering cell numbers both in naïve animals and during progressive nigrostriatal degeneration. LBT-3627 administration was linked to reductions of inflammatory microglia, increased survival of dopaminergic neurons, and improved striatal densities. While α-Syn overexpression resulted in reduced Treg activity, LBT-3627 rescued these functional deficits. This occurred in a dose-dependent manner closely mimicking neuroprotection. Taken together, these data provide the basis for the use of VIPR2 agonists as potent therapeutic immune modulating agents to restore Treg activity, attenuate neuroinflammation, and interdict dopaminergic neurodegeneration in PD. The data underscore an important role of immunity in PD pathogenesis
Selective VIP Receptor Agonists Facilitate Immune Transformation for Dopaminergic Neuroprotection in MPTP-Intoxicated Mice.
UNLABELLED: Vasoactive intestinal peptide (VIP) mediates a broad range of biological responses by activating two related receptors, VIP receptor 1 and 2 (VIPR1 and VIPR2). Although the use of native VIP facilitates neuroprotection, clinical application of the hormone is limited due to VIP\u27s rapid metabolism and inability to distinguish between VIPR1 and VIPR2 receptors. In addition, activation of both receptors by therapeutics may increase adverse secondary toxicities. Therefore, we developed metabolically stable and receptor-selective agonists for VIPR1 and VIPR2 to improve pharmacokinetic and pharmacodynamic therapeutic end points. Selective agonists were investigated for their abilities to protect mice against MPTP-induced neurodegeneration used to model Parkinson\u27s disease (PD). Survival of tyrosine hydroxylase neurons in the substantia nigra was determined by stereological tests after MPTP intoxication in mice pretreated with either VIPR1 or VIPR2 agonist or after adoptive transfer of splenic cell populations from agonist-treated mice administered to MPTP-intoxicated animals. Treatment with VIPR2 agonist or splenocytes from agonist-treated mice resulted in increased neuronal sparing. Immunohistochemical tests showed that agonist-treated mice displayed reductions in microglial responses, with the most pronounced effects in VIPR2 agonist-treated, MPTP-intoxicated mice. In parallel studies, we observed reductions in proinflammatory cytokine release that included IL-17A, IL-6, and IFN-γ and increases in GM-CSF transcripts in CD4(+) T cells recovered from VIPR2 agonist-treated animals. Moreover, a phenotypic shift of effector to regulatory T cells was observed. These results support the use of VIPR2-selective agonists as neuroprotective agents for PD treatment.
SIGNIFICANCE STATEMENT: Vasoactive intestinal peptide receptor 2 can elicit immune transformation in a model of Parkinson\u27s disease (PD). Such immunomodulatory capabilities can lead to neuroprotection by attenuating microglial activation and by slowing degradation of neuronal cell bodies and termini in MPTP-intoxicated mice. The protective mechanism arises from altering a Th1/Th2 immune cytokine response into an anti-inflammatory and neuronal sparing profile. These results are directly applicable for the development of novel PD therapies
Buffy the vampire slayer: what being Jewish has to do with it
This article examines the whiteness in the television series Buffy the Vampire Slayer. The author argues that the show’s overwhelming whiteness is a product of a generalized white anxiety about the numerical loss of white dominance across the United States and, in particular, in California. The article goes on to think through the role that Jewishness plays in the program, discussing the relationship between the apparently Anglo-American Buffy, played by a Jewish actor, and her sidekick, Willow, who is characterized as Jewish but is played by a non-Jewish actor. The evil master in the first series is given Nazi characteristics and the destruction that he wants to inflict carries connotations of the Holocaust. Structurally, Buffy is produced as the Jew who saves the United States from this demonic destruction. In this traumatic renarrativising, the Holocaust comes to stand for the white-experienced crisis of the loss of white supremacy in the United States. With this reading we can begin to understand the show’s popularity among early adult, predominantly white Americans
Rational design and characterization of β-peptides, a non-natural peptidomimetic scaffold
If the rules that govern complex atomic interactions are completely understood, then the greatest test would be to apply them to a new paradigm. The application of existing computational protein design methods and parameters to the β-peptide scaffold serves as this test. The paucity of structural data and lack of diverse examples employing this scaffold pose a great intellectual deficit in the ability to predict secondary structure and peptide-peptide interactions. I present tools, techniques and examples of successful rational β-peptide design. Through detailed modeling, rotameric preferences for this clans of compounds have been determined which were later validated experimentally. Using this infrastructure, secondary structure modeling has also been successfully achieved for this scaffold through the de novo design of a self-associating β-peptide oligomer. Finally, as a bridge to practical applications, the first transmembrane β-peptide was designed and characterized which also specifically binds its intended biological target integrin αIIB. Together, these efforts provide credibility to our ability to successfully apply highly parameterized design techniques to new scaffolds
Rational design and characterization of β-peptides, a non-natural peptidomimetic scaffold
If the rules that govern complex atomic interactions are completely understood, then the greatest test would be to apply them to a new paradigm. The application of existing computational protein design methods and parameters to the β-peptide scaffold serves as this test. The paucity of structural data and lack of diverse examples employing this scaffold pose a great intellectual deficit in the ability to predict secondary structure and peptide-peptide interactions. I present tools, techniques and examples of successful rational β-peptide design. Through detailed modeling, rotameric preferences for this clans of compounds have been determined which were later validated experimentally. Using this infrastructure, secondary structure modeling has also been successfully achieved for this scaffold through the de novo design of a self-associating β-peptide oligomer. Finally, as a bridge to practical applications, the first transmembrane β-peptide was designed and characterized which also specifically binds its intended biological target integrin αIIB. Together, these efforts provide credibility to our ability to successfully apply highly parameterized design techniques to new scaffolds