The autonomic nervous system regulates internal organs and peripheral circulation, which enables the maintenance of homeostasis in vertebrate species. One of the brain regions involved in autonomic and endocrine homeostasis regulation is the periventricular nucleus of the hypothalamus (PVN). The PVN is a unique site at which multiple input signals can be assessed and integrated. The regulation of the autonomic system by the PVN and, especially, the sympathetic flow, depends upon the integration of inhibitory and excitatory neurotransmitter action. The excitatory neurotransmitters such as glutamate and angiotensin II, and inhibitory neurotransmitters such as γ‑aminobutyric acid and nitric oxide, play a key role in the physiological function of the PVN. Moreover, arginine-vasopressin (AVP) and oxytocin (OXT) are important in the regulation of sympathetic system activity. The PVN is also crucial for maintaining cardiovascular regulation, with its integrity being pivotal for blood pressure regulation. Studies have shown that pre‑autonomic sympathetic PVN neurons increase blood pressure and the dysfunction of these neurons is directly related to elevated sympathetic nervous system activity under hypertension. Etiology of hypertension in patients is not fully known. Thus, understanding the role of PVN in the generation of hypertension may help to treat this cardiovascular disease. This review focuses on the PVN’s inhibitory and excitatory neurotransmitter interactions that regulate sympathetic system activity in physiological conditions and hypertension.

MOTS-c is a promising regulator of metabolism and energy homeostasis. While its effects have been studied in cell lines, our team aimed to investigate its influence on more complex structures—specifically, isolated pancreatic islets. We used two animal models: the rat, which is commonly studied, and the pig, which shares greater physiological similarities with humans. This study assessed the expression and secretion of insulin and glucagon, the expression of their receptors, cell viability, and cell death following MOTS-c treatment of the islets. Additionally, we examined how MOTS-c secretion is affected by different incubation media, such as the presence of free fatty acids, pancreatic hormones, and different glucose concentrations. The results indicate that MOTS-c impacts pancreatic islet physiology by, for example, reducing insulin and glucagon secretion and enhancing cell viability. Notably, the effects differed between the two species, which may be attributed to anatomical differences in their pancreatic islets or structural variations in rat and pig MOTS-c. These facts may lead to the conclusion that if MOTS-c may be helpful in human medicine, the pig model should be considered another valuable choice.

An unhealthy diet contributes significantly to the development of the global obesity epidemic and serves as a risk factor for fertility disorders. Moreover, maternal obesity leads to alterations in the reproductive capacity of the offspring via prenatal and postnatal programming. To replicate the impact of a diet rich in sugar and fat, which contributes to human obesity, we utilized a cafeteria (CAF) diet in rat mothers to investigate molecular and morphological consequences in the gonads of male and female progeny. Rat mothers were fed either standard (control) or CAF diet before and during pregnancy and lactation. Female and male offspring were sacrificed after weaning at different stages of reproductive maturation—females on postnatal days (PNDs) 30, 35, and 60, and males on PNDs 40 and 60. Ovaries and testis were examined for the expression of the kisspeptin system, including Kiss1, Kiss1r, estrogen (Esr1, Esr2), androgen (Ar), and luteinizing hormone choriogonadotropin (Lhcgr) receptors. Additionally, morphological parameters of the ovaries and testes were evaluated. Male offspring of CAF mothers showed: i) alterations in Ar and Kiss1 mRNA levels, and ii) decreased seminiferous tubules diameter and epithelium height, a reduced number of Sertoli cells, a lower percentage of seminiferous tubules with presented spermatozoa. Female offspring of CAF mothers exhibited: i) disturbed expression of Esr1, Esr2, Ar, and Lhcgr receptors in the ovaries, and ii) a diminished number of primordial and secondary follicles at PND 30 and primary follicles at PND 35. We concluded that the maternal CAF diet leads to sex-specific alterations in the reproductive parameters of offspring.

Long-lasting (chronic) stress leads to many adverse effects in living organisms. In this study, the city is perceived as an organism. Thus, the recognition of physiological mechanisms of stress response and coping with it in an organism will help identify and develop similar defence mechanisms in urban organisms. This study proposes a multidisciplinary approach and is aimed at applying the stress response mechanisms of living organisms to cities in order to build stress resilience in case of threat. The long-term impact assessment effects of the COVID-19 pandemic and the restrictions and lockdowns introduced are of particular interest. In the review, we present a theoretical, multidisciplinary approach to building a stress-resilient city suitable for academics and a global audience, and propose concrete strategies for city policymakers to cope with stressors at the level of its inhabitants as well as regulations and management. Mitigation, re-construction, and new urban governance have been recognised as such strategies and likened to shortand long-term stress responses of living organisms. Thus, we have offered policymakers a solution for building a resilient city. A novel model of environmental governance, propositions of intervention, and recommendations have been created that could be used by local city authorities to rebuild citizens’ resilience in post-pandemic times.

Peripherally restricted (‘second-generation’) cannabinoid CB₁ receptor (CB₁R) antagonists have been suggested to have therapeutic potential in numerous diseases. However, their effects on the cardiovascular system require further research. The peripheral CB₁R antagonist AM6545 failed to modify the decrease in blood pressure (BP) elicited by inhibition of anandamide degradation in spontaneously hypertensive rats. The aims of the present study were to examine the effect of AM6545 on BP and its interaction with endocannabinoid-evoked effects in deoxycorticosterone acetate (DOCA)-salt rats. For this purpose, we applied methanandamide (MethAEA), a stable analogue of anandamide, and URB597, an inhibitor of its degradation, in urethane-anesthetized animals. AM6545 did not affect BP by itself. MethAEA elicited a biphasic effect (a rise in BP, followed by its fall); both phases were antagonized by AM6545. URB597 induced a monophasic hypotensive effect, which was abolished by AM6545 in DOCA-salt rats but further enhanced in control animals. AM6545 also unmasked an additional increase in BP after URB597 in both groups of rats. In conclusion, AM6545 modifies the cardiovascular effects of endocannabinoids in hypertension in a model-dependent manner. The cardiovascular effects of CB₁R antagonists should be carefully evaluated when assessing their potential therapeutic significance, as they may unmask an increase in BP.