Neuroendocrine Regulation of Anxiety: Beyond the Hypothalamic‐Pituitary‐Adrenal Axis

Abstract

The central nervous system regulates and responds to endocrine signals, and this reciprocal relationship determines emotional processing and behavioural anxiety. Although the hypothalamicpituitary-adrenal (HPA) axis remains the best-characterised system for this relationship, other steroid and peptide hormones are increasingly recognised for their effects on anxiety-like behaviour and reward. The present review examines recent developments related to the role of a number of different hormones in anxiety, including pregnane neurosteroids, gut peptides, neuropeptides and hormonal signals derived from fatty acids. Findings from both basic and clinical studies suggest that these alternative systems may complement or occlude stress-induced changes in anxiety and anxiety-like behaviour. By broadening the scope of mechanisms for depression and anxiety, it may be possible to develop novel strategies to attenuate stress-related psychiatric conditions. The targets for these potential therapies, as discussed in this review, encompass multiple circuits and systems, including those outside of the HPA axis.

The relationship between symptom burden and systemic inflammation differs between male and female athletes following concussion

“…The mechanism(s) underlying the relationship observed in the current study between symptom burden and inflammation following SRC are unknown. However, given the strong influence of the neuroendocrine system on inflammation [44][45][46], its role in both brain injury [9,17,[47][48][49] and related symptomology [50][51][52][53] along with the differences in neuroendocrine biology between males and females [54][55][56], it is plausible that the stress-immune axis mediates the relationship between symptoms and inflammation following concussion. The two major arms of the body's stress system, the sympathetic nervous system (SNS) and the hypothalamic pituitary adrenal (HPA) axis can augment the immune system in numerous ways.…”

Homeostasis and the concept of 'interstitial fluids hierarchy': Relevance of cerebrospinal fluid sodium concentrations and brain temperature control (Review)

“…These aspects were further expanded (11) into the concept of 'predictive psychic homeostasis' that designates the capability to create (via the integrated actions of various brain-body mechanisms) a psycho-physical state of readiness that anticipates potential threats. Thus, predictive psychic homeostasis by avoiding possible future allostatic psycho-physical overloads is of a basic relevance for both eudaimonia and internal milieu homeostasis (8,11).…”

“…Thus, predictive psychic homeostasis by avoiding possible future allostatic psycho-physical overloads is of a basic relevance for both eudaimonia and internal milieu homeostasis (8,11). The survival value of predictive psychic homeostasis is emphasised by the evidence that it can sometimes override bodily homeostasis regulatory mechanisms (7,8).…”

“…It should be noted that both body homeostasis and psychic homeostasis are often jointly conditioned by the pattern of endocrine signaling (11,12). In particular, alterations of anterior pituitary hormones leading to somatic disturbances have been demonstrated in stress and mood disorders, including major depression (13).…”

Introduction

“…The review by Borrow et al . explores the interaction of steroid hormones (oestrogens and androgens) and neurosteroids (pregnanes) with peptide hormones (oxytocin, vasopressin, prolactin, neuropeptide Y, leptin, hypocretin, ghrelin), amino acid derived hormones (melatonin, histamine) and fatty acid‐derived hormones (prostaglandins) in the regulation of depression and anxiety.…”