Biology subjects

Aitta-Aho, T.

Publications and source records attributed to Aitta-Aho, T..

3 recordsLinked to original sources

bioRxiv2026

Effects of metabotropic 2/3-glutamate receptor activation and inactivation on activity-based anorexia model in mice.

Anorexia nervosa is an eating disorder disproportionately found in female human teens and young adults. It is often resistant to treatment, has a significant chance of relapse and is more lethal than other eating disorders, such as bulimia nervosa or Avoidant/Restrictive Food Intake Disorder (ARFID). There is no specific medication for the treatment of anorexia nervosa. Treatment consists of psychosocial means, psychotherapy, psychoeducation, and nutritional counseling. Medication is usually used for treating comorbidities such as anxiety or to decrease obsessive-compulsive tendencies. These medications cannot help the patient regain weight or treat core symptoms. Metabotropic 2/3-glutamate (mGluR2/3) receptor agonist (LY379268) and antagonist (LY341495) are promising pharmacological agents to treat psychiatric disorders. Both agonists and antagonists have been reported to have anxiolytic effects in different animal models of anxiety, while antagonists have shown antidepressant-like effects in preclinical studies. The activity-based anorexia (ABA) paradigm is used to model anorexia nervosa. It consists of giving mice access to a running wheel and restricting their feeding time. This causes mice to exercise more than mice without feeding time restriction and to eat less than mice without access to a moving running wheel. In this study, we subcutaneously injected female ABA model mice with a metabotropic 2/3-glutamate receptor agonist (LY379268) and antagonist (LY341495) in two experiments. Both compounds exacerbated weight loss by decreasing food intake as well as increasing physical activity. It can be concluded that the manipulation of mGluR2/3 receptors is detrimental for the ABA model and likely for anorexia nervosa as well. HighlightsO_LImGluR2/3 agonist LY379268 decreases food intake and body weight of the ABA model C_LIO_LImGluR2/3 antagonist LY341495 decreases food intake and body weight of the ABA model C_LIO_LIBoth agonist and antagonist produce the effect within 48 hours C_LIO_LIBoth the agonist and antagonist are detrimental to the ABA-model C_LI

neuroscience↗

bioRxiv2024

The BDNF/TrkB pathway in Somatostatin-expressing neurons suppresses cocaine-seeking behaviour

Cocaine addiction is a highly debilitating condition consisting of compulsive self-administration and seek for the substance of abuse, and its most challenging feature is the high rate of relapse. Addiction and relapse share similarities with neural plasticity which acts through the Brain-Derived Neurotrophic Factor and its receptor TrkB. Somatostatin (SST) expressing interneurons are involved in neuronal plasticity and are important in modulating cocaine-seeking behaviour in mice. We tested the role of TrkB in Somatostatin (SST)-expressing neurons in the extinction of cocaine-seeking behaviour, using mice in which TrkB has been knocked out specifically in SST neurons. We have observed that in these mice, once a cocaine-conditioned place preference is acquired, its extinction through seven days of extinction training is impaired, showing how this process relies on neural plasticity in SST neurons. When we promoted plasticity during extinction training using a light-activable TrkB in SST neurons in the prefrontal cortex of cocaine-conditioned mice, relapse of cocaine-seeking was prevented. Our data identify the critical role of TrkB-mediated plasticity within SST neurons in the extinction of and relapse to cocaine addiction.

neuroscience↗

bioRxiv2022

Gata2, Nkx2-2 and Skor2 form a transcription factor network regulating development of amidbrain GABAergic neuron subtype with characteristics of REM sleep regulatory neurons

The midbrain reticular formation is a mosaic of diverse GABAergic and glutamatergic neurons that have been associated with a variety of functions, including the regulation of sleep. However the molecular characteristics and development of the midbrain reticular formation neurons are poorly understood. As the transcription factor Gata2 is required for the development of all GABAergic neurons derived from the embryonic mouse midbrain, we hypothesized that the genes expressed downstream of Gata2 could contribute to the diversification of GABAergic neuron subtypes in this brain region. Here, we show that Gata2 is indeed required for the expression of several lineage-specific transcription factors in post-mitotic midbrain GABAergic neuron precursors. These include a homeodomain transcription factor Nkx2-2 and a SKI family transcriptional repressor Skor2, which are co-expressed in a restricted group of GABAergic precursors in the midbrain reticular formation. Both Gata2, and Nkx2-2 function is required for the expression of Skor2 in GABAergic precursors. In the adult mouse as well as rat midbrain, the Nkx2-2 and Skor2 expressing GABAergic neurons locate at the boundary of the ventrolateral periaqueductal gray and the midbrain reticular formation, an area shown to contain REM-off neurons regulating REM sleep. In addition to the characteristic localization, the Skor2 positive cells increase their activity upon REM sleep inhibition, send projections to a pontine region associated with sleep control and are responsive to orexins, consistent with the known properties of the midbrain REM-off neurons.

developmental biology↗