Neural activity, memory, and dementias: serotonergic markers
Dysfunctional memory seems to be a key component of diverse dementias and other neuropsychiatric disorders; unfortunately, no effective treatment exists for this, probably because of the absence of neural biomarkers accompanying it. Diverse neurotransmission systems have been implicated in memory, including serotonin or 5-hydroxytryptamine (5-HT). There are multiple serotonergic pharmacological tools, well-characterized downstream signaling in mammals' species and neural markers providing new insights into memory functions and dysfunctions. Serotonin in mammal species has multiple neural markers, including receptors (5-HT1–7), serotonin transporter, and volume transmission, which are present in brain areas involved in memory. Memory, amnesia, and forgetting modify serotonergic markers; this influence is bidirectional. Evidence shows insights and therapeutic targets and diverse approaches support the translatability of using neural markers and cerebral functions and dysfunctions, including memory formation and amnesia. For instance, 5-HT2A/2B/2C, 5-HT4, and 5-HT6 receptors are involved in tau protein hyperphosphorylation in Alzheimer’s disease. In addition, at least, 5-HT1A, 5-HT4, 5-HT6, and 5-HT7 receptors as well as serotonin transporter seem to be useful neural markers and therapeutic targets. Hence, available evidence supports the notion that several mechanisms cooperate to achieve synaptic plasticity or memory, including changes in the number of neurotransmitter receptors and transporters. Considering that memory is a key component of dementias, hence reversing or reducing memory deficits might positively affect them?