Increasing evidence suggests that a continuous release of histamine from mast cells occurs in the airways of asthmatic patients and that histamine may modulate functions of other inflammatory cells such as macrophages. In the present study histamine (10⁻⁹–10⁻⁶ M) increased in a concentration-dependent fashion the basal release of β-glucuronidase (EC₅₀ = 8.2 ± 3.5 × 10⁻⁹ M) and IL-6 (EC₅₀ = 9.3 ± 2.9 × 10⁻⁸ M) from human lung macrophages. Enhancement of β-glucuronidase release induced by histamine was evident after 30 min and peaked at 90 min, whereas that of IL-6 required 2–6 h of incubation. These effects were reproduced by the H₁ agonist (6-[2-(4-imidazolyl)ethylamino]-N-(4-trifluoromethylphenyl)heptane carboxamide but not by the H₂ agonist dimaprit. Furthermore, histamine induced a concentration-dependent increase of intracellular Ca²⁺ concentrations ([Ca²⁺]_i) that followed three types of response, one characterized by a rapid increase, a second in which [Ca²⁺]_i displays a slow but progressive increase, and a third characterized by an oscillatory pattern. Histamine-induced β-glucuronidase and IL-6 release and [Ca²⁺]_i elevation were inhibited by the selective H₁ antagonist fexofenadine (10⁻⁷–10⁻⁴ M), but not by the H₂ antagonist ranitidine. Inhibition of histamine-induced β-glucuronidase and IL-6 release by fexofenadine was concentration dependent and displayed the characteristics of a competitive antagonism (K_d = 89 nM). These data demonstrate that histamine induces exocytosis and IL-6 production from human macrophages by activating H₁ receptor and by increasing [Ca²⁺]_i and they suggest that histamine may play a relevant role in the long-term sustainment of allergic inflammation in the airways.

Secretory phospholipases A2 (sPLA2s) are a group of extracellular enzymes that release fatty acids at the sn-2 position of phospholipids. Group IIA sPLA2 has been detected in inflammatory fluids, and its plasma level is increased in inflammatory diseases. To investigate a potential mechanism of sPLA2-induced inflammation we studied the effect of group IA (from cobra venom) and group IIA (human synovial) sPLA2s on human macrophages. Both sPLA2s induced a concentration- and Ca2+-dependent, noncytotoxic release of β-glucuronidase (16.2 ± 2.4% and 13.1 ± 1.5% of the total content with groups IA and IIA, respectively). Both sPLA2s also increased the rate of secretion of IL-6 and enhanced the expression of IL-6 mRNA. Preincubation of macrophages with inhibitors of the hydrolytic activity of sPLA2 or cytosolic PLA2 did not influence the release of β-glucuronidase. Incubation of macrophages with p-aminophenyl-mannopyranoside-BSA (mp-BSA), a ligand of the mannose receptor, also resulted in β-glucuronidase release. However, while preincubation of macrophages with mp-BSA had no effect on β-glucuronidase release induced by group IIA sPLA2, it enhanced that induced by group IA sPLA2. A blocking Ab anti-mannose receptor inhibited both mp-BSA- and group IIA-induced β-glucuronidase release. Taken together, these data indicate that group IA and IIA sPLA2s activate macrophages with a mechanism independent from their enzymatic activities and probably related to the activation of the mannose receptor or sPLA2-specific receptors. The secretion of enzymes and cytokines induced by sPLA2s from human macrophages may play an important role in inflammation and tissue damage associated with the release of sPLA2s.

Worldwide population ageing is partly due to advanced standard of care, leading to increased incidence and prevalence of geriatric syndromes such as frailty and disability. Hence, the age at the onset of acute coronary syndromes (ACS) keeps growing as well. Moreover, ageing is a risk factor for both frailty and cardiovascular disease (CVD). Frailty and CVD in the elderly share pathophysiological mechanisms and associated conditions, such as malnutrition, sarcopenia, anemia, polypharmacy and both increased bleeding/thrombotic risk, leading to a negative impact on outcomes. In geriatric populations ACS is associated with an increased frailty degree that has a negative effect on re-hospitalization and mortality outcomes. Frail elderly patients are increasingly referred to cardiac rehabilitation (CR) programs after ACS; however, plans of care must be tailored on individual’s clinical complexity in terms of functional capacity, nutritional status and comorbidities, cognitive status, socio-economic support. Completing rehabilitative intervention with a reduced frailty degree, disability prevention, improvement in functional state and quality of life and reduction of re-hospitalization are the goals of CR program. Tools for detecting frailty and guidelines for management of frail elderly patients post-ACS are still debated. This review focused on the need of an early identification of frail patients in elderly with ACS and at elaborating personalized plans of care and secondary prevention in CR setting.

Atherogenic lipoproteins (particularly, very low-density lipoproteins, VLDL) are associated with subclinical atherosclerosis. The present study aims at evaluating whether routinely analysed lipid parameters are associated with carotid intima–media thickness, a proxy for subclinical atherosclerosis. Lipid parameters from 220 post-menopausal women undergoing ultrasound investigation of the carotid arteries were analysed. Forty-five percent of women showed subclinical atherosclerosis on carotid ultrasound. The mean carotid intima–media thickness was 1.26 ± 0.38 mm. The mean value of the non-HDL-C/HDL-C ratio was 3.1 ± 1.2. Univariate analysis showed a significant association between non-HDL-C/HDL-C ratio and intima–media thickness (r = 0.21, p = 0.001). After adjusting for cardiovascular risk factors (age, systolic blood pressure, smoking, body mass index Homeostasis model assessment: insulin resistance and high-sensitivity C-Reactive-Protein), multivariate analysis showed a significant association between non-HDL-C/HDL-C ratio and intima–media thickness (β = 0.039, p = 0.04). Logistic regression analysis showed that the highest tertile of the non-HDL-C/HDL-C ratio was associated with the presence of carotid plaques (OR = 3.47, p = 0.003). Finally, a strong correlation between non-HDL-C/HDL-C ratio and cholesterol bound to VLDL (r = 0.77, p < 0.001) has been found. Non-HDL-C/HDL-C ratio is associated with the presence of carotid atherosclerosis in post-menopausal women and is strongly correlated to VLDL-C levels.