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Complex and bidirectional relationships operate between the hypothalamic-pituitary-adrenal (HPA) axis and the immune system (IS) and either in vivo or in vitro evidence supports a physiological role of the HPA axis-IS network. A part of the well-known pharmacological effects of glucocorticoid hormones (GC) as immunodepressive agents, the direct effects of many HPA axis hormones on IS functions are actually documented also in physiologic conditions. Conversely, numerous IS soluble mediators are reported to affect the HPA axis functions at various steps of HPA axis regulation, in both physiologic and pathologic conditions. Stress and aging may represent two paradigmatic conditions to show the relevance of the bidirectional network between HPA axis and IS, as in both HPA activation and IS impairment are frequently coexistent. Finally, in the context of the wide spectrum of HIV-related HPA axis abnormalities, a case of a Cushing's syndrome associated to an acquired immunodeficiency syndrome (AIDS-related complex) in a 24-year-old homosexual drug abuser is reported.

We previously reported nocturnal plasma IL-1 beta (beta) increases during sleep in absence of stress-induced activation of hypothalamic-pituitary-adrenal (HPA) axis. In this paper we evaluate the presence of plasma IL-1 beta secretion in nine healthy volunteers (mean age 31.2 +/- 4.2) during post-prandial naps, after the administration of zolpidem, a benzodiazepine receptorial agonist. Although a significant increase in IL-1 beta plasma levels during spontaneous sleep was present in only four subjects when compared to those obtained during wake and induced-sleep, spontaneous sleep IL-1 beta mean plasma levels appeared slightly higher than both wake and induced-sleep values. Moreover, a negative correlation was present between IL-1 beta and cortisol (F) values obtained during the early afternoon (r = 7; p < 0.05). Our findings are consistent with a possible association of IL-1 beta secretion to physiologic sleep also during daytime spontaneous naps, with the presence of F influence on this phenomenon, and with the lack of IL-1 beta association to daytime naps after sleep-inducer pharmacological agents.

The hypothesis that alpha-adrenergic receptor blockade accounts for the ability of ergotamine to stop migraine attacks was tested, in migraine patients, in an experimental migraine model based on nitroderivative- induced attacks. In a preliminary single blind, placebo controlled study, thymoxamine, a prevalently post-synaptic alpha adrenergic receptor antagonist, was able to abort migraine attack in 9 out of 10 patients, as opposed to 2 out of 10 by placebo (p < 0.005 Fisher's exact test). In a subsequent randomized, crossover, placebo controlled double blind study, the ability of a selective alpha-1 adrenergic receptor agonist, methoxamine, to block ergotamine antimigraine effect was studied. In 26 patients migraine was induced in two separate tests and then ergotamine was administered once after methoxamine pretreatment and once after placebo; methoxamine was significantly more effective than placebo in blocking antimigraine effect of ergotamine (p = 0.0055 Fisher's exact test). These results support the hypothesis that ergotamine alpha-1 adrenolytic properties may account for its antimigraine effect suggesting that this action takes place outside the blood-brain barrier, since methoxamine can cross it very poorly. Ergotamine target structure could be the trigeminal innervation of the extracranial and/or dural vessels.

In 22 migraine patients and 5 healthy controls an investigation has been performed on lymphocyte subsets in basal conditions and 90 minutes after sublingual isosorbide dinitrate (IDN) administration. In all patients the drug assumption induced a typical migraine attack with increase in all examined lymphocyte subsets with except of NK cells. A statistically significant increase (p < 0.05) in T lymphocyte subsets we found during the crisis, whereas in healthy controls neither a migraine attack nor any modification in lymphocyte subsets could be observed. These results seem to confirm the immune alteration we have previously found in migraineous patients and suggest the possible role of IDN-stimulated endothelium not only in vasodilatation but also in production of substances responsible of the observed immune modifications.

The aim of the present study was to explore the association between memory impairment and primary headache. 100 headache patients (71 females, 29 males, mean age 35.6 +/- 13.8) and 20 healthy subjects (14 females, 6 males, mean age 37.3 +/- 12.1) as control group, were examined: a significant difference between the two groups was found (p < 0.001). The patients were divided into different groups according to the kind of headache, the use of analgesics, the pain side and the illness length: significant differences were found between patients who made a low use of analgesics and the others (p < 0.001); the illness duration also seems to be relevant in the progressive memory impairment, because it strengthens some immunologic and biochemical mechanisms able to favour a progressive mnemonic damage.

Patients with migraine without aura (MWA) display elevated amounts of Tumor Necrosis Factor (TNF)-alpha in their sera. In this study in 18 patients with MWA the in vivo effect of propranolol, a beta blocker agent, was evaluated with regard to the TNF serum levels before and after treatment. Results show that in 9 out 11 patients exaggerated serum concentrations of TNF reverted to normality after three months of therapy. Some hypotheses on the mechanisms of action of propranolol in terms of modulation of the immune response are formulated.

Our results suggest that CKs, in particular Interleukin-1 and Tumor Necrosis Factor (TNF)-alpha, are involved in the pathogenesis of some neurological disorders and HIV infection. Infact, we observed an exaggerated spontaneous release of TNF-alpha in patients with migraine without aura. Furthermore, in a broad spectrum of patients with HIV-infection we have also found increased amounts of serum TNF-alfa and IL-1. Interestingly, a strict correlation between plasma lipopolysaccharide (LPS) and IL-1 or TNF-alpha levels seems to exist in both group of patients, thus indicating that LPS could account for the production of CKs in the course of the above diseases.

Cytokines (CKs) are involved in the mechanisms of sleep induction, and, in particular, interleukin-1 (IL-1) and tumor necrosis factor-alpha seem to play an important role in the slow-wave sleep. Here are reported two cases of normal sleep and altered sleep in which plasma levels of IL-1 beta have been determined. In the subject with a normal sleep a dramatic increase of this CK has been observed, while beta-endorphin levels were reduced. In the light of these findings, the role of sleep in the host protection is discussed.

Many evidences support the existence of a bilateral connection between the thymic gland and the hypothalamic-pituitary-adrenal axis (HPAA). In this respect, neurohormones such as the adrenal corticotropin hormone and glucocorticoids cause thymic involution, while the growth hormone and the prolactin upregulate thymic functions. On the other hand, a thymic hormone, the thymosin fraction 5, activates the HPAA, thus closing-up the regulatory loop between immune system and nervous system. In this review, a clinical trial with two thymic hormones (Timostimolina and Thymopentin) in agoraphobic patients with phagocytic dysfunctions is reported. Results obtained indicate that both substances lead to a partial and temporary immunological recovery, since a further depression of phagocytic activities occurs in coincidence with panic attack. The use of alternative immunomodulators in these patients is discussed.

Benzodiazepines (BDZ) are psychotropic drugs largely used in patients with affective disorders. As far as their effects on the immune system are concerned, a few studies have been carried out until now. Diazepam is inhibitory in vitro for the phagocytic functions and the antibody synthesis, being its action mediated via specific receptors on immunocompetent cells. On the contrary, alprazolam results to be enhancing for the antibacterial activity exerted by normal human peripheral blood T lymphocytes in vitro. Taken together, these data point out the different role which BDZ play on the immune response.

The effects of two benzodiazepines, diazepam and alprazolam, have been evaluated on the in vitro antibacterial activity exerted by human peripheral blood lymphocytes (PBL). Results demonstrate that diazepam has no influence on this PBL function, while alprazolam is able to enhance this activity in six out of nine normal donors considered. The possible therapeutical implications of these data are discussed.

Migraine without aura (MWA) is a clinical condition characterized by multiple immune deficits, which may play an important role in the pathogenesis of the disease. In this respect, previous studies have demonstrated that patients with MWA exhibit profound dysfunctions of phagocytosis and killing exerted by polymorphonuclear cells (PMN) and monocytes. This may correlate with the increased frequency of infectious processes observed in these patients. The overall results suggested to evaluate the presence of circulating cytokines (CKs) in subjects affected by MWA. In particular, the present data point out an exaggerated spontaneous release of tumor necrosis factor (TNF)-alpha in a group of MWA individuals, which correlates with detectable levels of bacterial lipopolysaccharides (LPS) in their plasma. In view of the different biological activities displayed by TNF-alpha in the host, such as effects on the nervous and vascular systems, hemodynamics modifications and demyelinating properties, the intervention of this CK in the pathogenesis of MWA will be discussed.

Bacterial lipopolysaccharides (LPS) or endotoxins are potent triggers of the cytokine (CK) cascade. These CKs are immune mediators which produce many biological effects and could play a detrimental rather than beneficial role in the host. In this review emphasis will be placed on the participation of two CKs, tumor necrosis factor [TNF-alpha and interleukin (IL-1) beta], in the pathogenetic development of HIV infection. We have found that TNF and IL-1 circulate in exaggerated amounts in the blood of HIV-infected subjects from the earliest phases of infection. Furthermore, we have observed a strict correlation between plasma LPS and IL-1 beta levels, thus indicating that endotoxins could account for the production of CKs in the course of HIV infection. Finally, the demyelinating role of TNF-alpha either in experimental models or in the course of AIDS dementia complex is outlined.

Serum levels of tumor necrosis factor (TNF)-alpha/cachectin have been evaluated in 20 patients with Migraine without Aura (MwA) versus 17 patients with Chronic Type Tension Headache (CTTH). Results show an exaggerated release of TNF-alpha/cachectin in sera of patients affected by MwA, while in CTTH patients TNF serum concentration is comparable to that observed in normal donors. Some hypotheses are formulated in order to clarify the TNF-alpha/cachectin spontaneous production and its biological significance in patients with MwA.