TY  - JOUR
A1  - Metzner, Valentin
A1  - Herzog, Gloria
A1  - Heckel, Tobias
A1  - Bischler, Thorsten
A1  - Hasinger, Julia
A1  - Otto, Christoph
A1  - Fassnacht, Martin
A1  - Geier, Andreas
A1  - Seyfried, Florian
A1  - Dischinger, Ulrich
T1  - Liraglutide + PYY\(_{3-36}\) combination therapy mimics effects of Roux-en-Y bypass on early NAFLD whilst lacking-behind in metabolic improvements
JF  - Journal of Clinical Medicine
N2  - Background: Treatment options for NAFLD are still limited. Bariatric surgery, such as Roux-en-Y gastric bypass (RYGB), has been shown to improve metabolic and histologic markers of NAFLD. Glucagon-like-peptide-1 (GLP-1) analogues lead to improvements in phase 2 clinical trials. We directly compared the effects of RYGB with a treatment using liraglutide and/or peptide tyrosine tyrosine 3-36 (PYY\(_{3-36}\)) in a rat model for early NAFLD. Methods: Obese male Wistar rats (high-fat diet (HFD)-induced) were randomized into the following treatment groups: RYGB, sham-operation (sham), liraglutide (0.4 mg/kg/day), PYY\(_{3-36}\) (0.1 mg/kg/day), liraglutide+PYY\(_{3-36}\), and saline. After an observation period of 4 weeks, liver samples were histologically evaluated, ELISAs and RNA sequencing + RT-qPCRs were performed. Results: RYGB and liraglutide+PYY\(_{3-36}\) induced a similar body weight loss and, compared to sham/saline, marked histological improvements with significantly less steatosis. However, only RYGB induced significant metabolic improvements (e.g., adiponectin/leptin ratio 18.8 ± 11.8 vs. 2.4 ± 1.2 in liraglutide+PYY\(_{3-36}\)- or 1.4 ± 0.9 in sham-treated rats). Furthermore, RNA sequencing revealed a high number of differentially regulated genes in RYGB treated animals only. Conclusions: The combination therapy of liraglutide+PYY\(_{3-36}\) partly mimics the positive effects of RYGB on weight reduction and on hepatic steatosis, while its effects on metabolic function lack behind RYGB.
KW  - liraglutide
KW  - GLP-1
KW  - peptide tyrosine tyrosine (PYY)
KW  - peptide tyrosine tyrosine 3-36 (PYY\(_{3-36}\))
KW  - RYGB
KW  - gastric bypass
KW  - obesity
KW  - NASH
KW  - NAFLD
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-255244
SN  - 2077-0383
VL  - 11
IS  - 3
ER  - 
TY  - JOUR
A1  - Karikari, Akua A.
A1  - McFleder, Rhonda L.
A1  - Ribechini, Eliana
A1  - Blum, Robert
A1  - Bruttel, Valentin
A1  - Knorr, Susanne
A1  - Gehmeyr, Mona
A1  - Volkmann, Jens
A1  - Brotchie, Jonathan M.
A1  - Ahsan, Fadhil
A1  - Haack, Beatrice
A1  - Monoranu, Camelia-Maria
A1  - Keber, Ursula
A1  - Yeghiazaryan, Rima
A1  - Pagenstecher, Axel
A1  - Heckel, Tobias
A1  - Bischler, Thorsten
A1  - Wischhusen, Jörg
A1  - Koprich, James B.
A1  - Lutz, Manfred B.
A1  - Ip, Chi Wang
T1  - Neurodegeneration by α-synuclein-specific T cells in AAV-A53T-α-synuclein Parkinson’s disease mice
JF  - Brain, Behavior, and Immunity
N2  - Background
Antigen-specific neuroinflammation and neurodegeneration are characteristic for neuroimmunological diseases. In Parkinson’s disease (PD) pathogenesis, α-synuclein is a known culprit. Evidence for α-synuclein-specific T cell responses was recently obtained in PD. Still, a causative link between these α-synuclein responses and dopaminergic neurodegeneration had been lacking. We thus addressed the functional relevance of α-synuclein-specific immune responses in PD in a mouse model.
Methods
We utilized a mouse model of PD in which an Adeno-associated Vector 1/2 serotype (AAV1/2) expressing human mutated A53T-α-Synuclein was stereotactically injected into the substantia nigra (SN) of either wildtype C57BL/6 or Recombination-activating gene 1 (RAG1)\(^{-/-}\) mice. Brain, spleen, and lymph node tissues from different time points following injection were then analyzed via FACS, cytokine bead assay, immunohistochemistry and RNA-sequencing to determine the role of T cells and inflammation in this model. Bone marrow transfer from either CD4\(^{+}\)/CD8\(^{-}\), CD4\(^{-}\)/CD8\(^{+}\), or CD4\(^{+}\)/CD8\(^{+}\) (JHD\(^{-/-}\)) mice into the RAG-1\(^{-/-}\) mice was also employed. In addition to the in vivo studies, a newly developed A53T-α-synuclein-expressing neuronal cell culture/immune cell assay was utilized.
Results
AAV-based overexpression of pathogenic human A53T-α-synuclein in dopaminergic neurons of the SN stimulated T cell infiltration. RNA-sequencing of immune cells from PD mouse brains confirmed a pro-inflammatory gene profile. T cell responses were directed against A53T-α-synuclein-peptides in the vicinity of position 53 (68–78) and surrounding the pathogenically relevant S129 (120–134). T cells were required for α-synuclein-induced neurodegeneration in vivo and in vitro, while B cell deficiency did not protect from dopaminergic neurodegeneration.
Conclusions
Using T cell and/or B cell deficient mice and a newly developed A53T-α-synuclein-expressing neuronal cell culture/immune cell assay, we confirmed in vivo and in vitro that pathogenic α-synuclein peptide-specific T cell responses can cause dopaminergic neurodegeneration and thereby contribute to PD-like pathology.
KW  - Parkinson’s disease
KW  - α-synuclein-specific T cells
KW  - neurodegeneration
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300600
VL  - 101
SP  - 194
EP  - 210
ER  -