Zinc-bound metallothioneins and immune plasticity: lessons from very old mice and humans

The capacity of the remodelling immune responses during stress (named immune plasticity) is fundamental to reach successful ageing. We herein report two pivotal experimental models in order to demonstrate the relevance of the immune plasticity in ageing and successful ageing. These two experimental models will be compared with the capacity in remodelling the immune response in human centenarians. With regard to experimental models, one model is represented by the circadian rhythms of immune responses, the other one is the immune responses during partial hepatectomy/liver regeneration (pHx). The latter is suggestive because it mimics the immunosenescence and chronic inflammation 48 h after partial hepatectomy in the young through the continuous production of IL-6, which is the main cause of immune plasticity lack in ageing. The constant production of IL-6 leads to abnormal increments of zinc-bound Metallothionein (MT), which is in turn unable in zinc release in ageing. As a consequence, low zinc ion bioavailability appears for thymic and extrathymic immune efficiency, in particular of liver NKT cells bearing TCR γδ. The remodelling during the circadian cycle and during pHx of zinc-bound MT confers the immune plasticity of liver NKT γδ cells and NK cells in young and very old mice, not in old mice. With regard to human centenarians and their capacity in remodelling the immune response with respect to elderly, these exceptional individuals display low zinc-bound MT associated with: a) satisfactory intracellular zinc ion availability, b) more capacity in zinc release by MT, c) less inflammation due to low gene expression of IL-6 receptor (gp130), d) increased levels of IFN-gamma and number of NKT cell bearing TCR γδ. Moreover, some polymorphisms for MT tested in PBMCs from human donors are related to successful ageing. In conclusion, zinc-bound MT homeostasis is fundamental to confer the immune plasticity that is a condition "sine qua non" to achieve healthy ageing and longevity

Quinupristin/dalfopristin Bonding in Combination with Intraperitoneal Antibiotics Prevent Infection of Knitted Polyester Graft Material in a Subcutaneous Rat Pouch Model Infected with Resistant Staphylococcus epidermidis

AbstractObjective: to investigate the efficacy of quinupristin/dalfopristin in the prevention of prosthetic graft infection in a rat subcutaneous pouch model.Methods: graft infections were established in the subcutaneous tissue of 140 male Wistar rats by implantation of Dacron prostheses followed by topical inoculation withStaphylococcus epidermidis with intermediate resistance to glycopeptides. The study included one group without contamination, one contaminated group without prophylaxis, one contaminated group that received 50mg/l quinupristin/dalfopristin-soaked graft, one contaminated group that received 10mg/kg intraperitoneal levofloxacin, one contaminated group that received 3mg/kg intraperitoneal doxycycline, and two contaminated groups that received 50mg/l quinupristin/dalfopristin-soaked plus 10mg/kg intraperitoneal levofloxacin or 3mg/kg intraperitoneal doxycycline. Each group included 20 animals. The grafts were removed after 7 days and evaluated by quantitative culture.Results: quinupristin/dalfopristin showed a significantly higher efficacy than levofloxacin and doxycycline, even though quantitative graft cultures for rats that received only quinupristin/dalfopristin-soaked graft showed bacterial growth. Otherwise, the efficacy of levofloxacin was similar to that of doxycycline. Only the group treated with quinupristin/dalfopristin combined with levofloxacin or doxycycline showed no evidence of staphylococcal infection.Conclusions: quinupristin/dalfopristin as adjunctive topical antibiotic prophylaxis can be useful for the prevention of vascular graft infections caused by staphylococcal strains with high levels of resistance

RNAIII-inhibiting Peptide and/or Nisin Inhibit Experimental Vascular Graft Infection with Methicillin-susceptible and Methicillin-resistant Staphylococcus epidermidis

AbstractObjective. To investigate the efficacy of RNAIII-inhibiting peptide (RIP) and nisin as prophylactic agents in a rat model of vascular graft infection.Design. Prospective, randomized, controlled animal study.Materials. Two hundred and twenty adult male Wistar rats. Staphylococcus epidermidis ATCC 12228 and one clinical isolate of methicillin-resistant S. epidermidis. Drugs: RIP, nisin and rifampin.Methods. Graft infections were established in the dorsal subcutaneous tissue by implantation of 1 cm2 sterile Dacron grafts, followed by topical bacterial inoculation: grafts were retrieved at 7 days. The study included a control group (without inoculation) and two series composed of five groups for each staphylococcal strain: one contaminated group that did not receive any antibiotic prophylaxis, three contaminated groups that received grafts soaked with 10 mg/l RIP, 10 mg/l nisin, 10 mg/l rifampin, or RIP+nisin. The main outcome measure was the extent of bacterial at graft harvest.Results. The bacterial counts for methicillin-resistant S. epidermidis on explanted grafts were 6.1±2.8×102, 7.8±3.0×103 and 5.5±2.9×104 for RIP, nisin and rifampin, respectively. RIP and nisin used in combination reduced the bacterial count to <10. The results for S. epidermidis were similar.Conclusions. RIP and nisin could be used in combination to coat medical devices to prevent drug resistant S. epidermidis infections

Zinc and ageing: third Zincage conference

The importance of Zn for optimal functioning of the immune system and antioxidant stress response is well documented. Zn homeostasis influences development and function of immune cells, activity of stress-related and antioxidant proteins [metallothioneins (MT), chaperones, ApoJ, Poly(ADP-Ribose) polymerase-1 (PARP-1) and Methionione Sulfoxide Reductase (Msr), Superoxide Dismutase (SOD)], and helps to maintain genomic integrity and stability. During ageing, the intake of Zn decreases due to inadequate diet and/or intestinal malabsorption, contributing to frailty, general disability and increased incidence of age-related degenerative diseases (cancer, infections and atherosclerosis). Although many factors contributing to Zn deficiency have been identified, the biochemical markers of Zn deficiency as well as the possibility to achieve relevant health benefits through Zn supplementation in the elderly are still a matter for evaluation. Taking into account that Zn homeostasis is regulated by proteins and enzymes for which polymorphisms have been previously found to be associated with successful/unsuccessful ageing, genetic screening might be of added value in evaluating the individual response to Zn supplementation. Biochemical, immunological, dietary and genetic studies aimed at understanding the impact of Zn in healthy ageing, the effect of Zn supplementation in the elderly and finally formulating a rationale for the promotion of correct Zn supplementation were discussed at the international Zincage conference held in Ancona in January 2007

Postoperative trends and prognostic values of inflammatory and nutritional biomarkers after liver transplantation for hepatocellular carcinoma

11noPreoperative inflammatory biomarkers such as the Platelet-to-Lymphocyte Ratio (PLR) and the Neutrophil-to-Lymphocyte Ratio (NLR) strongly predict the outcome in surgically treated patients with hepatocellular carcinoma (HCC), while nutritional biomarkers such as the Controlling Nutritional Status (CONUT) and the Prognostic Nutritional Index (PNI) show an analogue prognostic value in hepatic resection (HR) but not in liver transplant (LT) cases. Data on the impact of LT on the inflammatory and nutritional/metabolic function are heterogeneous. Therefore, we investigated the post-LT trend of these biomarkers up to postoperative month (POM) 12 in 324 HCC patients treated with LT. Inflammatory biomarkers peaked in the early post-LT period but at POM 3 leveled off at values similar (NLR) or higher (PLR) than pre-LT ones. CONUT and PNI worsened in the early post-LT period, but at POM 3 they stabilized at significantly better values than pre-LT. In LT recipients with an overall survival &gt;1 year and no evidence of early HCC recurrence, 1 year post-LT NLR and PNI independently predicted patient overall survival, while 1 year post-LT PLR independently predicted late tumor recurrence. In conclusion, at 1 year post-LT, the nutritional status of liver-transplanted HCC patients significantly improved while their inflammatory state tended to persist. Consequently, post-LT PLR and NLR maintained a prognostic value for LT outcome while post-LT CONUT and PNI acquired it.openopenopenPravisani R.; Mocchegiani F.; Isola M.; Lorenzin D.; Adani G.L.; Cherchi V.; De Martino M.; Risaliti A.; Lai Q.; Vivarelli M.; Baccarani U.Pravisani, R.; Mocchegiani, F.; Isola, M.; Lorenzin, D.; Adani, G. L.; Cherchi, V.; De Martino, M.; Risaliti, A.; Lai, Q.; Vivarelli, M.; Baccarani, U

Evolution of minimally invasive techniques and surgical outcomes of ALPPS in Italy: a comprehensive trend analysis over 10 years from a national prospective registry

BackgroundSince 2012, Associating Liver Partition and Portal vein ligation for Staged hepatectomy (ALPPS) has encountered several modifications of its original technique. The primary endpoint of this study was to analyze the trend of ALPPS in Italy over a 10-year period. The secondary endpoint was to evaluate factors affecting the risk of morbidity/mortality/post-hepatectomy liver failure (PHLF).MethodsData of patients submitted to ALPPS between 2012 and 2021 were identified from the ALPPS Italian Registry and evaluation of time trends was performed.ResultsFrom 2012 to 2021, a total of 268 ALPPS were performed within 17 centers. The number of ALPPS divided by the total number of liver resections performed by each center slightly declined (APC = - 2.0%, p = 0.111). Minimally invasive (MI) approach significantly increased over the years (APC = + 49.5%, p = 0.002). According to multivariable analysis, MI completion of stage 1 was protective against 90-day mortality (OR = 0.05, p = 0.040) as well as enrollment within high-volume centers for liver surgery (OR = 0.32, p = 0.009). Use of interstage hepatobiliary scintigraphy (HBS) and biliary tumors were independent predictors of PHLF.ConclusionsThis national study showed that use of ALPPS only slightly declined over the years with an increased use of MI techniques, leading to lower 90-day mortality. PHLF still remains an open issue

NK cell compartment in patients with coronary heart disease

<p>Abstract</p> <p>Background</p> <p>Viral and bacterial infections have been considered as a risk factor for Coronary Heart Disease (CHD). NK cells, as a first line of defense against those infections, may play a role in CHD development. Thus, the main aim of our study was to determine NK cell compartment in patients with CHD undergoing coronary artery by-pass grafting.</p> <p>Results</p> <p>Ninety three patients with CHD were included into the study; the control group consisted of 49 healthy volunteers. As compared to controls, CHD patients had lower NK cytotoxic activity. CHD group had also a decreased absolute number and percentage of total NK cells and CD3-CD56dim cytotoxic NK subset. In addition, we observed tendency toward lower percentage of the CD3-CD56bright regulatory NK subset and CD3-CD56+IFN-γ+ cells in CHD patients.</p> <p>Conclusion</p> <p>These data indicate that CHD is associated with an impairment of NK cells compartment.</p

ZIP8 Zinc Transporter: Indispensable Role for Both Multiple-Organ Organogenesis and Hematopoiesis In Utero

Previously this laboratory characterized Slc39a8-encoded ZIP8 as a Zn2+/(HCO3–)2 symporter; yet, the overall physiological importance of ZIP8 at the whole-organism level remains unclear. Herein we describe the phenotype of the hypomorphic Slc39a8(neo/neo) mouse which has retained the neomycin-resistance gene in intron 3, hence causing significantly decreased ZIP8 mRNA and protein levels in embryo, fetus, placenta, yolk sac, and several tissues of neonates. The Slc39a8(neo) allele is associated with diminished zinc and iron uptake in mouse fetal fibroblast and liver-derived cultures; consequently, Slc39a8(neo/neo) newborns exhibit diminished zinc and iron levels in several tissues. Slc39a8(neo/neo) homozygotes from gestational day(GD)-11.5 onward are pale, growth-stunted, and die between GD18.5 and 48 h postnatally. Defects include: severely hypoplastic spleen; hypoplasia of liver, kidney, lung, and lower limbs. Histologically, Slc39a8(neo/neo) neonates show decreased numbers of hematopoietic islands in yolk sac and liver. Low hemoglobin, hematocrit, red cell count, serum iron, and total iron-binding capacity confirmed severe anemia. Flow cytometry of fetal liver cells revealed the erythroid series strikingly affected in the hypomorph. Zinc-dependent 5-aminolevulinic acid dehydratase, required for heme synthesis, was not different between Slc39a8(+/+) and Slc39a8(neo/neo) offspring. To demonstrate further that the mouse phenotype is due to ZIP8 deficiency, we bred Slc39a8(+/neo) with BAC-transgenic BTZIP8-3 line (carrying three extra copies of the Slc39a8 allele); this cross generated viable Slc39a8(neo/neo)_BTZIP8-3(+/+) pups showing none of the above-mentioned congenital defects–proving Slc39a8(neo/neo) causes the described phenotype. Our study demonstrates that ZIP8-mediated zinc transport plays an unappreciated critical role during in utero and neonatal growth, organ morphogenesis, and hematopoiesis

The immune system and the impact of zinc during aging

The trace element zinc is essential for the immune system, and zinc deficiency affects multiple aspects of innate and adaptive immunity. There are remarkable parallels in the immunological changes during aging and zinc deficiency, including a reduction in the activity of the thymus and thymic hormones, a shift of the T helper cell balance toward T helper type 2 cells, decreased response to vaccination, and impaired functions of innate immune cells. Many studies confirm a decline of zinc levels with age. Most of these studies do not classify the majority of elderly as zinc deficient, but even marginal zinc deprivation can affect immune function. Consequently, oral zinc supplementation demonstrates the potential to improve immunity and efficiently downregulates chronic inflammatory responses in the elderly. These data indicate that a wide prevalence of marginal zinc deficiency in elderly people may contribute to immunosenescence