Neurosteroids and translocator protein 18 kDa (TSPO) in depression: implications for synaptic plasticity, cognition, and treatment options.

There is need for novel fast acting treatment options in affective disorders. 3α-reduced neurosteroids such as allopregnanolone are powerful positive allosteric modulators of GABAA receptors and target also extrasynaptic receptors. Their synthesis is mediated by the translocator protein 18 kDa (TSPO). TSPO ligands not only promote endogenous neurosteroidogenesis, but also exert a broad spectrum of functions involving modulation of mitochondrial activity and acting as anti-inflammatory and neuroregenerative agents. Besides affective symptoms, in depression cognitive impairment can be frequently observed, which may be ameliorated through targeting of extrasynaptic GABAA receptors either via TSPO ligands or exogenously administered 3α-reduced neurosteroids. Interestingly, recent findings indicate an enhanced activation of the complement system, e.g., enhanced expression of C1q, both in depression and dementia. It is of note that benzodiazepines have been shown to reduce long-term potentiation and to cause cognitive decline. Intriguingly, TSPO may be crucial in mediating the effects of benzodiazepines on synaptic pruning. Here, we discuss how benzodiazepines and TSPO may interfere with synaptic pruning. Moreover, we highlight recent developments of TSPO ligands and 3α-reduced neurosteroids as therapeutic agents. Etifoxine is the only clinically available TSPO ligand so far and has been studied in anxiety disorders. Regarding 3α-reduced neurosteroids, brexanolone, an intravenous formulation of allopregnanolone, has been approved for the treatment of postpartum depression and zuranolone, an orally available 3α-reduced neurosteroid, is currently being studied in major depressive disorder and postpartum depression. As such, 3α-reduced neurosteroids and TSPO ligands may constitute promising treatment approaches for affective disorders.

Electroconvulsive therapy in a patient with hypertrophic cardiomyopathy: A case report.

The use of electroconvulsive therapy (ECT) in patients with underlying cardiac disease like hypertrophic cardiomyopathy (HCM) remains without satisfactory clinical guidelines. We provide a case report of successful application of ECT in a 43-year-old patient with bipolar disorder and comorbid HCM, including detailed diagnostic information and outlining key clinical considerations.

Reactive increase of cerebrospinal fluid white blood cell count after lumbar puncture: Fact or fiction?

Lumbar puncture (LP) is commonly used in the diagnostic workup of neurological patients, often to exclude inflammatory diseases of the central nervous system. In clinical practice, an increase of white blood cell count (WBC) in the cerebrospinal fluid (CSF) after a LP is often assumed as reactive to the first puncture. Scientific evidence of this hypothesis, however, is lacking. Retrospective review of laboratory parameters was done by analyzing CSF of patients who had at least two LPs between 2012 and 2016 in a single center. Inclusion criteria were a normal CSF WBC in the first LP as well as absence of any underlying disease typically associated with increased CSF WBC. A total of 176 patients (age 57.0 ± 17.6) with 260 serial LPs were included. No significant effect on the CSF WBC (1.2 ± 1.1 vs 1.4 ± 1.4/µl, p = .17), lactat and protein level between consecutive punctures was found after a second LP. In the subgroup of 104 patients who had two LPs within ten days, only one (0.96%) showed a mild abnormal CSF WBC (9 leukocytes/µl) in the second LP. A raise of CSF WBC after LP is rare and not commonly found; therefore, it should lead to careful exclusion of other, especially inflammatory diseases. The needle size is important to minimize the trauma during LP and seems to have an influence on the rate of reactive increase of CSF WBC after LP.

No modulatory effects by transcranial static magnetic field stimulation of human motor and somatosensory cortex.

BACKGROUND: Recently, it was reported that the application of a static magnetic field by placing a strong permanent magnet over the scalp for 10 min led to an inhibition of motor cortex excitability for at least 6 min after removing the magnet. When placing the magnet over the somatosensory cortex, a similar inhibitory after effect could be observed as well. OBJECTIVE: Our aim was to replicate the inhibitory effects of transcranial static magnetic field stimulation in the motor and somatosensory system. METHODS: The modulatory effect of static magnetic field stimulation was investigated in three experiments. In two experiments motor cortex excitability was measured before and after 10 or 15 min of magnet application, respectively. The second experiment included a sham condition and was designed in a double-blinded manner. In a third experiment, paired-pulse SSEPs were measured pre and four times post positioning the magnet over the somatosensory cortex for 10 min on both hemispheres, respectively. The SSEPs of the non stimulated hemisphere served as control condition. RESULTS: We did not observe any systematic effect of the static magnetic field neither on motor cortex excitability nor on SSEPs. Moreover, no SSEP paired-pulse suppression was found. CONCLUSION: We provide a detailed analysis of possible confounding factors and differences to previous studies on tSMS. After all, our results could not confirm the static magnetic field effect.