TY  - JOUR
A1  - Gutknecht, Lise
A1  - Araragi, Naozumi
A1  - Merker, Sören
A1  - Waider, Jonas
A1  - Sommerlandt, Frank M. J.
A1  - Mlinar, Boris
A1  - Baccini, Gilda
A1  - Mayer, Ute
A1  - Proft, Florian
A1  - Hamon, Michel
A1  - Schmitt, Angelika G.
A1  - Corradetti, Renato
A1  - Lanfumey, Laurence
A1  - Lesch, Klaus-Peter
T1  - Impacts of Brain Serotonin Deficiency following Tph2 Inactivation on Development and Raphe Neuron Serotonergic Specification
JF  - PLoS One
N2  - Brain serotonin (5-HT) is implicated in a wide range of functions from basic physiological mechanisms to complex behaviors, including neuropsychiatric conditions, as well as in developmental processes. Increasing evidence links 5-HT signaling alterations during development to emotional dysregulation and psychopathology in adult age. To further analyze the importance of brain 5-HT in somatic and brain development and function, and more specifically differentiation and specification of the serotonergic system itself, we generated a mouse model with brain-specific 5-HT deficiency resulting from a genetically driven constitutive inactivation of neuronal tryptophan hydroxylase-2 (Tph2). Tph2 inactivation (Tph2-/-) resulted in brain 5-HT deficiency leading to growth retardation and persistent leanness, whereas a sex- and age-dependent increase in body weight was observed in Tph2+/- mice. The conserved expression pattern of the 5-HT neuron-specific markers (except Tph2 and 5-HT) demonstrates that brain 5-HT synthesis is not a prerequisite for the proliferation, differentiation and survival of raphe neurons subjected to the developmental program of serotonergic specification. Furthermore, although these neurons are unable to synthesize 5-HT from the precursor tryptophan, they still display electrophysiological properties characteristic of 5-HT neurons. Moreover, 5-HT deficiency induces an up-regulation of 5-HT\(_{1A}\) and 5-HT\(_{1B}\) receptors across brain regions as well as a reduction of norepinephrine concentrations accompanied by a reduced number of noradrenergic neurons. Together, our results characterize developmental, neurochemical, neurobiological and electrophysiological consequences of brain-specific 5-HT deficiency, reveal a dual dose-dependent role of 5-HT in body weight regulation and show that differentiation of serotonergic neuron phenotype is independent from endogenous 5-HT synthesis.
KW  - lacking
KW  - knock-out mice
KW  - energy expenditure
KW  - locomotor activity
KW  - 5-HT transporter
KW  - anxiety like
KW  - receptors
KW  - behavior
KW  - tryptophan
KW  - nucleus
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133728
VL  - 7
IS  - 8
ER  - 
TY  - JOUR
A1  - Popp, Sandy
A1  - Schmitt-Böhrer, Angelika
A1  - Langer, Simon
A1  - Hofmann, Ulrich
A1  - Hommers, Leif
A1  - Schuh, Kai
A1  - Frantz, Stefan
A1  - Lesch, Klaus-Peter
A1  - Frey, Anna
T1  - 5-HTT Deficiency in Male Mice Affects Healing and Behavior after Myocardial Infarction
JF  - Journal of Clinical Medicine
N2  - Anxiety disorders and depression are common comorbidities in cardiac patients. Mice lacking the serotonin transporter (5-HTT) exhibit increased anxiety-like behavior. However, the role of 5-HTT deficiency on cardiac aging, and on healing and remodeling processes after myocardial infarction (MI), remains unclear. Cardiological evaluation of experimentally naïve male mice revealed a mild cardiac dysfunction in ≥4-month-old 5-HTT knockout (−/−) animals. Following induction of chronic cardiac dysfunction (CCD) by MI vs. sham operation 5-HTT−/− mice with infarct sizes >30% experienced 100% mortality, while 50% of 5-HTT+/− and 37% of 5-HTT+/+ animals with large MI survived the 8-week observation period. Surviving (sham and MI < 30%) 5-HTT−/− mutants displayed reduced exploratory activity and increased anxiety-like behavior in different approach-avoidance tasks. However, CCD failed to provoke a depressive-like behavioral response in either 5-Htt genotype. Mechanistic analyses were performed on mice 3 days post-MI. Electrocardiography, histology and FACS of inflammatory cells revealed no abnormalities. However, gene expression of inflammation-related cytokines (TGF-β, TNF-α, IL-6) and MMP-2, a protein involved in the breakdown of extracellular matrix, was significantly increased in 5-HTT−/− mice after MI. This study shows that 5-HTT deficiency leads to age-dependent cardiac dysfunction and disrupted early healing after MI probably due to alterations of inflammatory processes in mice.
KW  - chronic heart failure
KW  - myocardial infarction
KW  - serotonin transporter deficient mice
KW  - anxiety
KW  - depression
KW  - behavior
KW  - inflammation
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242739
SN  - 2077-0383
VL  - 10
IS  - 14
ER  -