Takotsubo syndrome (TTS) is a cardiomyopathy that presents clinically as a transient and reversible left ventricular wall motion abnormality (LVWMA) that can recover spontaneously within hours to weeks. Studies have shown that it mainly affects older people. Postmenopausal women in particular have an increased prevalence. Physical and emotional stress are widely discussed and generally recognized trigger factors. As age also appears to play a major role in the development of TTS, this review will take a closer look at age- and gender-specific aspects. First and foremost, postmenopausal women and the associated lower oestrogen concentration should be mentioned here. Another important role is played by the hypothalamic-pituitary-adrenal (HPA) axis and the associated glucocorticoid-dependent negative feedback and the resulting immune response. Inflammaging is another term that is increasingly used in connection with TTS. In the following, these risk factors are considered in more detail and linked to the increased sympathetic activity as a possible consequence of chronic stress. Based on the imbalance between the sympathetic and parasympathetic nervous system, we venture an explorative proposal and would like to present a new possible therapeutic approach.

Breast cancer brain metastasis (BCBM) is a challenging condition with limited treatment options and poor prognosis. Understanding the interactions between tumor cells and the blood-brain barrier (BBB) is critical for developing novel therapeutic strategies. One promising target is estrogen receptor β (ERβ), which promotes the expression of key tight junction proteins, sealing the BBB and reducing its permeability. In this study, we investigated the effects of 17β-estradiol (E2) and the selective ERβ agonist diarylpropionitrile (DPN) on endothelial and cancer cells. Western blot analysis revealed the expression patterns of ERs in these cell lines, and estrogen treatment upregulated claudin-5 expression in brain endothelial cells. Using in vitro models of the BBB, we found that DPN treatment significantly increased BBB tightness about suppressed BBB transmigration activity of representative HER2-positive (BT-474) and triple-negative (MDA-MB-231) breast cancer cell lines. However, the efficacy of DPN treatment decreased when cancer cells were pre-differentiated in the presence of E2. Our results support ERβ as a potential target for the prevention and treatment of BCBM and suggest that targeted vector-based approaches may be effective for future preventive and therapeutic implications.