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Biomedical subjects

Roberto Paganelli

Publications and source records attributed to Roberto Paganelli.

At least 19 recordsLinked to original sources

Determinants of platelet activation in Alzheimer's disease.

OBJECTIVES: To investigate the rate of platelet thromboxane (TX) biosynthesis and its determinants in Alzheimer's disease. METHODS AND RESULTS: A cross-sectional comparison of urinary 11-dehydro-TXB(2) and 8-iso-prostaglandin (PG)F(2alpha) (markers of in vivo platelet activation and lipid peroxidation, respectively), plasma Vitamin E, C-reactive protein (CRP), tumor necrosis factor (TNF)-alpha and interleukin (IL)-6, was carried-out in 44 Alzheimer patients and 44 matched controls. To investigate the cyclooxygenase (COX)-isoform involved in TXA(2) biosynthesis, nine Alzheimer patients were treated with low-dose aspirin (100mg/d) or rofecoxib (25mg/d) for 4 days. Urinary 11-dehydro-TXB(2) and 8-iso-PGF(2alpha) were significantly higher in Alzheimer patients than in controls (Median: 1983.5 versus 517.5pg/mg creatinine and 938.5 versus 304.0pg/mg creatinine, p<0.0001, respectively), with a significant correlation between the two metabolites (rho=0.75, p<0.0001). An inverse correlation was observed between Vitamin E and both urinary metabolites (8-iso-PGF(2alpha): R(s)=-0.51, p=0.0004; 11-dehydro-TXB(2): R(s)=-0.44, p=0.0026) in Alzheimer patients. No difference was found in CRP, TNF-alpha and IL-6 levels between the two groups. Urinary 11-dehydro-TXB(2) was significantly reduced by aspirin, but not by rofecoxib, consistently with a COX-1-mediated TXA(2) biosynthesis. 8-iso-PGF(2alpha) excretion was not modified by either COX-inhibitor, consistently with its oxygen radical-catalyzed formation. CONCLUSIONS: Platelet activation is persistently enhanced in Alzheimer's disease. This is related, at least in part, to increased lipid peroxidation associated with inadequate levels of Vitamin E.

Aged↗

Markers of inflammation, vitamin E and peripheral nervous system function: the InCHIANTI study.

BACKGROUND: Aging of the peripheral nervous system is associated with several morphologic and functional changes, including a decrease of the nerve conduction velocity. There is evidence that these changes contribute to age-related-decline in muscle strength, sensory discrimination, and autonomic responses. The aim of this study was to characterize the decline in nerve conduction velocity in the peripheral nervous system over the aging process and to identify factors that, independent of age, affect nerve conduction velocity. METHODS: We measured motor nerve conduction velocity of the right superficial peroneal nerve using a standard neurophysiologic technique in a population-based sample of subjects aged between 20 and 103 years old enrolled in the InCHIANTI study. RESULTS: Average conduction velocities in the peripheral nerve decreased linearly with age in both sexes. We found that diabetes, cognitive impairment, uric acid, sIL-6R and alpha-tocopherol were significant predictors of nerve conduction velocity independently of the potential confounding effect of age, sex, sex x age interaction term, height, lymphocytes, neutrophils number, alpha1 and alpha2-globulin serum protein. CONCLUSIONS: Our findings are consistent with the hypothesis that inflammation and inadequate antioxidant defenses are associated with accelerated decline of nerve conduction velocity over the aging process.

Adult↗

Inhibitory effects of cadmium on peripheral blood mononuclear cell proliferation and cytokine release are reversed by zinc and selenium salts.

Zinc (Zn) and selenium (Se) exert regulatory activities on immune functions, while cadmium (Cd) is an immunotoxic agent. The object of this study was to detect effects of 10(-4), 10(-5), and 10(-6) M Cd sulphate, Zn sulphate, and sodium selenite, and their combinations on human peripheral blood mononuclear cell (PBMC) proliferation and IFN-gamma and TNF-alpha production. Only 10(-5) M Zn sulphate significantly enhanced spontaneous PBMC proliferation, which was unaffected by the other salts. At 10(-4) and 10(-5) M, Cd sulphate exerted a dose-response inhibitory action on phytohemagglutinin- (PHA-) stimulated PBMC proliferation and cytokine release, while 10(-4) M and 10(-5) M Zn sulphate and 10(-5) M sodium selenite induced a stimulatory effect on both proliferation and cytokine release; 10(-4) M sodium selenite enhanced only the PBMC proliferation; at 10(-6) M, none of the salts changed the PHA-stimulated immune activity. Moreover, 10(-4) and 10(-5) M Zn and 10(-5) M Se strongly upregulated IFN-gamma (a Th1 cytokine) release, even in presence of 10(-5) M Cd, and reduced the inhibitory effects of Cd on PBMC proliferation and TNF-alpha release. This study confirms that Zn and Se both strongly enhance cytokine release induced by mitogenic stimulation, showing also that Zn acts with a broader range of concentrations than Se. This suggests that dietary excess of Se may not have beneficial effects.

Cadmium Compounds↗

IL-4 in vitro production is upregulated in Alzheimer's disease patients treated with acetylcholinesterase inhibitors.

Cytokines appear to be involved in the pathogenesis of Alzheimer's Disease (AD). Their modulation by treatment has been investigated only in a few studies. The aim of our study was to evaluate the effect of acetylcholinesterase inhibitors (AChEI) on Interleukin-4 (IL-4) production in AD patients. IL-4 levels were measured by ELISA on peripheral blood mononuclear cell cultures in the presence or absence of Concanavalin A or Phytohaemagglutinin. Linear regression analysis shows that patients who have been treated, have higher levels of IL-4 independently from age, gender and comorbidity. The increased production of IL-4 in AChEI treated patients might represent an additional mechanism through which AChEI act on AD progression.

Aged↗

In vitro effects of platinum compounds on lymphocyte proliferation and cytokine release.

In vitro immune effects of Pt compounds of occupational and/or environmental importance, or those used in cancer treatment were studied. Spontaneous and PHA-stimulated proliferation of peripheral blood mononuclear cells (PBMC) and in vitro release of TNF-alpha, IFN-gamma, and IL-5 were assessed in presence of high and very low concentrations of Pt salts: 10(-4) and 10(-7) M (NH4)2[PtCl6], (NH4)2[PtCl4], PtCl4, PtCl2, Na2PtI6, and cis-diaminedichloroPt (CisPt). Spontaneous and PHA-stimulated PBMC proliferation were both inhibited by 10(-4) M (NH4)2[PtCl6] and (NH4)2[PtCl4], while only PHA-stimulated proliferation was inhibited by 10(-4) M CisPt, without significant effects of the other Pt salts. TNF-alpha release from PBMC was reduced by 10(-4) M (NH4)2[PtCl6] and INF-gamma release was reduced by 10(-4) and 10(-7) M hexa- and tetrachloroplatinate and 10(-4) M Na2PtI6, but not by other Pt salts. IL-5 release (related to the Th2 immune response) was inhibited by 10(-4) M (NH4)2[PtCl6], (NH4)2[PtCl4] and Na2PtI6, but it was enhanced by both 10(-4) and 10(-7) M PtCl4. PtCl2 did not influence the immune effects. The study shows Pt salts have immune effects and their potency is ranked in the following order: (NH4)2[PtCl6] > (NH4)2[PtCl4] > Na2PtI6 and CisPt > PtCl4 > PtCl2. These results indicate that certain Pt salts affect lymphocyte proliferation and cytokine release. The intracellular mechanisms responsible for such effects have not been identified.

Adult↗

Different effects of platinum, palladium, and rhodium salts on lymphocyte proliferation and cytokine release.

The effects of graded concentrations of Pt, Pd, and Rh salts on spontaneous and PHA-stimulated peripheral blood mononuclear cell (PBMC) proliferation and IFN-gamma, TNF-alpha, and IL-5 release were the focus of this study. Spontaneous PBMC proliferation was inhibited by all 10(-4) M salts (with the exception of PtCl2), while it was enhanced by 10(-5) M PtCl2 as well as by 10(-5) and 10(-6) M (NH4)2[RhCl6] and RhCl3 (but not by 10(-7) M salts). Pt, Pd, and Rh compounds showed similar effects on PHA-stimulated PBMC proliferation and cytokine release; however, the effects on IFN-gamma release were stronger. Thus, 10(-4) and 10(-5) M (NH4)2[PtCl6] and 10(-4) M (NH4)2[PtCl4] inhibited the PHA-stimulated immune activity; 10(-4) M PtCl2 did not exert activity, while 10(-6) M (NH4)2[PtCl6] and 10(-5) and 10(-6) M (NH4)2[PtCl4] and PtCl2 enhanced PBMC proliferation and/or cytokine release. (NH4)2[PdCl6] showed stronger dose-related inhibitory effects (present also at 10(-7) M concentration) on PHA-stimulated proliferation and cytokine release than (NH4)2[PdCl4], PdCl2, or Rh salts; the inhibitory activity of (NH4)2[RhCl6] was slightly higher than that of RhCl3. In conclusion, this study shows that: (a) the immune capacity of Pt, Pd, and Rh depends on speciation; (b) low concentrations of Pt salts stimulate spontaneous and PHA-stimulated immune responses; (c) the in vitro activity of Pd compounds (which are only inhibitory) is higher than that of Pt and Rh salts. These findings are consistent with the observations that sensitization and allergic contact dermatitis in response to Pd are increased in the general population, although the roles of cross-sensitization to Pd and Ni are difficult to determine.

Adult↗

Serum IL-1beta levels in health and disease: a population-based study. 'The InCHIANTI study'.

Interleukin-1 plays a role in normal homeostasis and in the inflammatory response which is deemed to be responsible for the development of major chronic diseases that are highly prevalent in the elderly. Aim of this study is to evaluate the factors influencing the serum levels of Interleukin-1 beta, in a large and representative population. Data were from the InCHIANTI project, a study of factors contributing to the decline of mobility in late life, which sampled people living in two sites in the surroundings of Florence. Blood samples were obtained from 1,292 participants and frozen aliquots were stored at -80 degrees C. The serum levels of several cytokines were measured by enzyme linked immunosorbent assay using an ultrasensitive commercial kit. Interleukin-1 beta serum levels were associated with congestive heart failure (p > 0.001) and angina (p = 0.02), with Ca2+ serum levels (p = 0.02), and with a history of dyslipidemia (p = 0.05). We found no association between serum IL-1beta level and age, sex, consumption of cardioactive drugs and serum levels of IL-1Ra, IL-6, sIL-6R, IL-10 and TNF-alpha. Our data could lend support to the hypothesis that IL-1beta is mainly involved in the functional alterations of cardiomyocytes under conditions marked by mononuclear cell infiltration and by downregulation of calcium.

Aging↗

Different sensitivity to apoptosis in cells of monocytic or lymphocytic origin chronically infected with human immunodeficiency virus type-1.

Apoptotic death of CD4+ T lymphocytes is a major cause of the immunodeficiency caused by human immunodeficiency virus (HIV), but it is still unclear how this process precisely occurs. To characterize a potentially useful cellular model, we have analyzed the tendency of chronically HIV-infected CD4+ human cell lines of different origin to undergo apoptosis. We studied ACH-2 and U1 lines, derived from the CD4+ T-cell A301 and the promonocytic U937 cell lines, respectively, and induced apoptosis via several stimuli that trigger different pathways. Their capacity to regulate plasma membrane CD95 expression and to produce soluble CD95 was also analyzed. Using staurosporine, TNF-alpha plus cycloheximide, and gamma-radiations, we observed that ACH-2 were more sensitive to programmed cell death than A301, while U1 were less sensitive than U937. Both infected cell types had a lower sensitivity to CD95-induced apoptosis; the analysis of changes in mitochondrial membrane potential corroborated these observations. Plasma membrane CD95 was similarly regulated in all cell types, which, however, presented a different capacity to produce soluble CD95 molecules. Our in vitro results may offer a new perspective for developing further studies on the pathogenesis of HIV infection. A chronically infected cell line of lymphocytic origin is more susceptible to apoptosis than its parental cell type, while infected monocytic cells are less sensitive than their uninfected counterpart. Thus, it is possible to hypothesize that one of the reasons by which circulating monocytes survive and represent a viral reservoir is the capacity of HIV to decrease the sensitivity to apoptosis of this cell type. However, further studies on ex-vivo collected fresh cells, as well as on other cell lines, are urgently needed to confirm such hypothesis.

Apoptosis↗

Effects of resveratrol on lymphocyte proliferation and cytokine release.

Resveratrol, synthesized in dietary plants and contained in wine, has been reported to play a beneficial role in certain cardiovascular regulatory mechanisms and to inhibit carcinogenesis by activating immune and inflammatory responses and apoptosis. The object of this study was to elucidate the "in vitro" effects of different concentrations of resveratrol (10(-4), 10(-5), and 10(-7) M) on human peripheral blood mononuclear cell (PBMC) proliferation and cytokine release. Spontaneous PBMC proliferation was unaffected by resveratrol, while the compound at 10(-4) M inhibited (69%) the PHA-stimulated PBMC proliferation. The proliferation stimulation index (ie, the ratio of PHA-stimulated PBMC proliferation/spontaneous PBMC proliferation) of cultures containing 10(-4) M resveratrol was very low in relation to the control, while the proliferation stimulation index values at 10(-5) and 10(-7) M were similar and slightly higher (without statistical significance), respectively. At 10(-4) M, resveratrol strongly inhibited PHA-stimulated IFN-gamma and TNF-alpha release from PBMC, but it did not cause inhibition at 10(-5) or 10(-7) M. The concomitant immune effects of resveratrol on PBMC proliferation and release of IFN-gamma and TNF-alpha may be explained by an inhibitory effect on transcription factor NF-kappaB. This study suggests that resveratrol, which is typically present in red wine at about 10(-5) M, is unlikely to cause inhibitory immune effects. However, a stimulatory effect of low concentrations of resveratrol on the immune system cannot be excluded.

Adult↗

In vitro effects of nickel-sulphate on immune functions of normal and nickel-allergic subjects: a regulatory role for zinc.

Nickel hypersensitivity represents a very common human disease state, mainly occurring in females, defined as allergic contact dermatitis. Ni is a transition metal whose activity may be modulated by congeners. Zinc, an essential component for living organisms, has been shown to counteract Ni effects in patients with Ni hypersensitivity. We analysed immune responses to both Ni and Zn in healthy subjects and patients with allergic contact dermatitis to Ni. Our in vitro results show that Ni modulates surface receptors expression, reduces phytohemagglutinin (PHA)-driven lymphoproliferation, and upregulates some proinflammatory cytokines production, including interferon (IFN)-gamma. Zn also induced CD4+ lymphocyte proliferation, but it abolished or reduced most Ni-mediated effects. Our data are consistent with the hypothesis that Zn and Ni, as part of the heavy transition metals, may exchange roles in immune-mediated phenomena leading to expression of allergic contact dermatitis.

Adult↗

Structural changes of the erythrocyte as a marker of non-insulin-dependent diabetes: protective effects of N-acetylcysteine.

Prooxidant-antioxidant imbalance was considered as a hallmark of age-associated, non-insulin-dependent diabetes (NIDD). The aim of this ex vivo study was to investigate possible implications of oxidative stress in the integrity and function of red blood cells (RBCs) from NIDD patients. Morphometric and analytical cytology studies were conducted. The results showed: (i) significant alterations of RBC ultrastructure; (ii) relevant changes of spectrin cytoskeleton; (iii) altered insulin receptor distribution; and (iv) that treatment with the antioxidizing drug N-acetylcysteine was capable of significantly counteracting these changes. These results suggest a reconsideration of RBC integrity as a possible progression marker in NIDD.

Acanthocytes↗

Galectins and their ligands: amplifiers, silencers or tuners of the inflammatory response?

Recent evidence has implicated galectins and their ligands as master regulators of immune cell homeostasis. Whereas some members of this family, such as galectin-3, behave as amplifiers of the inflammatory cascade, others, such as galectin-1, trigger homeostatic signals to shut off T-cell effector functions. These carbohydrate-binding proteins, identified by shared consensus amino acid sequences and affinity for beta-galactoside-containing sugars, participate in the homeostasis of the inflammatory response, either by regulating cell survival and signaling, influencing cell growth and chemotaxis, interfering with cytokine secretion, mediating cell-cell and cell-matrix interactions or influencing tumor progression and metastasis. The current wealth of new information promises a future scenario in which individual members of the galectin family or their ligands will be used as powerful anti-inflammatory mediators and selective modulators of the immune response.

Amino Sugars↗

In vitro effects of vanadate on human immune functions.

Vanadium (V) is an element with wide industrial applications and environmental release. The object of this study was to determine the in vitro effects of high (10(-4) M) and low (10(-7) M) concentrations of sodium metavanadate (NaVO3) on cultured peripheral blood mononuclear cell (PBMC) proliferation, cytokine release, CD expression, and granulocyte O2- production. At 10(-4) and 10(-7) M, NaVO3 did not modify PBMC proliferation in the absence of phytohemagglutinin (PHA). On the other hand, 10(-4) M NaVO3 reduced by -25% the PBMC proliferation in PHA-stimulated cultures, with a significant reduction of the stimulation index (SI) of blastogenesis. Moreover, 10(-4 M NaVO3 significantly reduced the release of IFN-gamma by PHA-stimulated PBMCs, and 10(-7) M NaVO3 significantly enhanced the release of TNF-alpha. In addition, IL-5 release was significantly inhibited by high concentration of sodium metavanadate and significantly enhanced by low concentration of NaVO3. Neither 10(-4) nor 10(-7) M NaVO3 modified the expression of CD3+, CD4+, CD8+, or CD56+ in PHA-stimulated and unstimulated lymphocytes. Finally, 10(-4) M NaVO3 reduced the granulocyte production of O2- by about 70%, while 10(-7) vanadate reduced its production to a lesser extent. These results show that 10(-4) M NaVO3 exerts inhibitory effects on PBMCs, while at 10(-7) M it exerts a stimulatory action with a slight shift of the immune response towards a Th2-type response. This investigation suggests that environmental V can have important effects on the human immune system.

Adult↗

Proinflammatory cytokines in sera of elderly patients with dementia: levels in vascular injury are higher than those of mild-moderate Alzheimer's disease patients.

Cognitive functions display a progressive impairment with ageing, and this is thought to be due to the accumulation of neuronal loss or acute and/or repeated microvascular accidents. Chronic damage to the brain cortex lead to decreasing ability of elderly subjects to cope with daily events and ultimately result in loss of self-sufficiency. Since proinflammatory cytokines have been implicated both in cerebrovascular injury due to atherosclerosis and in Alzheimer's disease (AD), we investigated 70 elderly subjects with neurocognitive and functional impairment. Diagnosis was established in 54, the others were included in the "mixed" group. Sera were collected and stored at -70 degrees C until measurement of IL-1beta and TNF-alpha, performed by commercial ELISA kits. Data obtained were analysed with respect to other socio-demographic, psychoneurological and clinical variables. The results show that serum TNF-alpha was lower in mild-moderate AD compared to severe AD and dementias due to vascular disease, as well as the TNF-alpha/IL-1beta ratio. Both cytokines showed a significant relationship with age. Our study suggests that proinflammatory cytokines serum profiles seem to discriminate between mild-moderate AD and vascular or mixed forms of dementia. Furthermore, it offers new evidence of a strong implication of inflammatory mechanisms in atherosclerosis, more than in less severe AD.

Aged↗

Thymic sensitivity to hypoxic condition in young and old rats. Age-dependent expression of NF-kappaB.

Oxygen keeps the entire enzymatic machinery in its physiological state. Senescence is associated with damage caused by oxidative stress, affecting also the immune system. In this study the effect of chronic hypoxia for 12 days on young and elderly rat thymus was investigated. The significant changes in cell thymic organization in young and old-aged rat thymus, with redistribution of thymic cells and stroma, were even more marked after prolonged hypoxia. These were further associated to down-regulation of NF-kappaB expression in young rats but up-regulation in old rats. Reorganization of thymic compartments together with disregulated expression of transcription factors, mainly expressed by 'common' thymocytes, may be related to an altered function under hypoxic conditions, inducing opposite responses in young and aged thymuses, probably related to different states of basal oxidative stress.

Age Factors↗

Common variable immunodeficiency and eosinophilic fasciitis.

The association of eosinophilic fasciitis and immunological defects is rare, especially hypogammaglobulinemia. We report a case of eosinophilic fasciitis occurring in a female, 53 years old, with common variable immunodeficiency. The diagnosis of common variable immunodeficiency was established by chance observation of persistently low levels of all immunoglobulin classes unrelated to protein loss or immunosuppressive treatment, one year after the appearance of eosinophilic fasciitis, which is usually characterized by hypergammaglobulinemia. Our description may prompt the investigation of an increased rate of simultaneous occurrence of eosinophilic fasciitis and common variable immunodeficiency.

Agammaglobulinemia↗