Antibody response after two doses of the SARS-CoV-2 Comirnaty vaccine in a Covid-19 positive and Covid-19 negative Italian healthcare workers cohort.

BACKGROUND: Extensive vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now universally regarded as one of the most effective strategies for counteracting the current pandemic. The durability of the immune response of available vaccines is not known, therefore the quantitative dynamics of serum anti-S antibodies after Comirnaty vaccine in health care workers (HCW) of Desio Hospital was conducted. METHODS: 51 previously infected and 198 not infected HCW, from Desio, Italy were enrolled in the study. Comirnaty double dose schedule was completed by each subject. Specific anti-S antibodies against the SARS-CoV-2 S protein were measured by ECLIA in sequential blood samples. RESULTS: A significant difference was observed beginning at pre priming dose (T0) of the anti-S antibodies between the two subgroups which persisted throughout the study (4 months). A significant reduction occurred after 4 months post-priming dose (T3). Finally, a subgroup of low and late responders with an increasing trend was found. CONCLUSIONS: Specific anti-S antibodies are significantly decreased 4 months post priming dose of Comirnaty vaccine although prior COVID-19 infection seems to escalate humoral response. Further evaluation concerning antibody persistence beyond this point, and the proportion of neutralizing antibodies with higher affinity towards SARS-CoV-2 is needed, especially in naїve and immunosuppressed subjects.

Histone deacetylase 3 regulates the inflammatory gene expression programme of rheumatoid arthritis fibroblast-like synoviocytes.

OBJECTIVES: Non-selective histone deacetylase (HDAC) inhibitors (HDACi) have demonstrated anti-inflammatory properties in both in vitro and in vivo models of rheumatoid arthritis (RA). Here, we investigated the potential contribution of specific class I and class IIb HDACs to inflammatory gene expression in RA fibroblast-like synoviocytes (FLS). METHODS: RA FLS were incubated with pan-HDACi (ITF2357, givinostat) or selective HDAC1/2i, HDAC3/6i, HDAC6i and HDAC8i. Alternatively, FLS were transfected with HDAC3, HDAC6 or interferon (IFN)-α/ß receptor alpha chain (IFNAR1) siRNA. mRNA expression of interleukin (IL)-1ß-inducible genes was measured by quantitative PCR (qPCR) array and signalling pathway activation by immunoblotting and DNA-binding assays. RESULTS: HDAC3/6i, but not HDAC1/2i and HDAC8i, significantly suppressed the majority of IL-1ß-inducible genes targeted by pan-HDACi in RA FLS. Silencing of HDAC3 expression reproduced the effects of HDAC3/6i on gene regulation, contrary to HDAC6-specific inhibition and HDAC6 silencing. Screening of the candidate signal transducers and activators of transcription (STAT)1 transcription factor revealed that HDAC3/6i abrogated STAT1 Tyr701 phosphorylation and DNA binding, but did not affect STAT1 acetylation. HDAC3 activity was required for type I IFN production and subsequent STAT1 activation in FLS. Suppression of type I IFN release by HDAC3/6i resulted in reduced expression of a subset of IFN-dependent genes, including the chemokines CXCL9 and CXCL11. CONCLUSIONS: Inhibition of HDAC3 in RA FLS largely recapitulates the effects of pan-HDACi in suppressing inflammatory gene expression, including type I IFN production in RA FLS. Our results identify HDAC3 as a potential therapeutic target in the treatment of RA and type I IFN-driven autoimmune diseases.

Lysine deacetylase inhibition prevents diabetes by chromatin-independent immunoregulation and ß-cell protection.

Type 1 diabetes is due to destruction of pancreatic ß-cells. Lysine deacetylase inhibitors (KDACi) protect ß-cells from inflammatory destruction in vitro and are promising immunomodulators. Here we demonstrate that the clinically well-tolerated KDACi vorinostat and givinostat revert diabetes in the nonobese diabetic (NOD) mouse model of type 1 diabetes and counteract inflammatory target cell damage by a mechanism of action consistent with transcription factor--rather than global chromatin--hyperacetylation. Weaning NOD mice received low doses of vorinostat and givinostat in their drinking water until 100-120 d of age. Diabetes incidence was reduced by 38% and 45%, respectively, there was a 15% increase in the percentage of islets without infiltration, and pancreatic insulin content increased by 200%. Vorinostat treatment increased the frequency of functional regulatory T-cell subsets and their transcription factors Gata3 and FoxP3 in parallel to a decrease in inflammatory dendritic cell subsets and their cytokines IL-6, IL-12, and TNF-α. KDACi also inhibited LPS-induced Cox-2 expression in peritoneal macrophages from C57BL/6 and NOD mice. In insulin-producing ß-cells, givinostat did not upregulate expression of the anti-inflammatory genes Socs1-3 or sirtuin-1 but reduced levels of IL-1ß + IFN-γ-induced proinflammatory Il1a, Il1b, Tnfα, Fas, Cxcl2, and reduced cytokine-induced ERK phosphorylation. Further, NF-κB genomic iNos promoter binding was reduced by 50%, and NF-κB-dependent mRNA expression was blocked. These effects were associated with NF-κB subunit p65 hyperacetylation. Taken together, these data provide a rationale for clinical trials of safety and efficacy of KDACi in patients with autoimmune disease such as type 1 diabetes.

Specific inhibition of histone deacetylase 8 reduces gene expression and production of proinflammatory cytokines in vitro and in vivo.

ITF2357 (generic givinostat) is an orally active, hydroxamic-containing histone deacetylase (HDAC) inhibitor with broad anti-inflammatory properties, which has been used to treat children with systemic juvenile idiopathic arthritis. ITF2357 inhibits both Class I and II HDACs and reduces caspase-1 activity in human peripheral blood mononuclear cells and the secretion of IL-1ß and other cytokines at 25-100 nm; at concentrations >200 nm, ITF2357 is toxic in vitro. ITF3056, an analog of ITF2357, inhibits only HDAC8 (IC50 of 285 nm). Here we compared the production of IL-1ß, IL-1α, TNFα, and IL-6 by ITF2357 with that of ITF3056 in peripheral blood mononuclear cells stimulated with lipopolysaccharide (LPS), heat-killed Candida albicans, or anti-CD3/anti-CD28 antibodies. ITF3056 reduced LPS-induced cytokines from 100 to 1000 nm; at 1000 nm, the secretion of IL-1ß was reduced by 76%, secretion of TNFα was reduced by 88%, and secretion of IL-6 was reduced by 61%. The intracellular levels of IL-1α were 30% lower. There was no evidence of cell toxicity at ITF3056 concentrations of 100-1000 nm. Gene expression of TNFα was markedly reduced (80%), whereas IL-6 gene expression was 40% lower. Although anti-CD3/28 and Candida stimulation of IL-1ß and TNFα was modestly reduced, IFNγ production was 75% lower. Mechanistically, ITF3056 reduced the secretion of processed IL-1ß independent of inhibition of caspase-1 activity; however, synthesis of the IL-1ß precursor was reduced by 40% without significant decrease in IL-1ß mRNA levels. In mice, ITF3056 reduced LPS-induced serum TNFα by 85% and reduced IL-1ß by 88%. These data suggest that specific inhibition of HDAC8 results in reduced inflammation without cell toxicity.

Histone deacetylase inhibitors modulate interleukin 6-dependent CD4+ T cell polarization in vitro and in vivo.

Histone deacetylase (HDAC) inhibitors have been associated primarily with an anti-proliferative effect in vitro and in vivo. Recent data provide evidence for an anti-inflammatory potency of HDAC inhibitors in models of experimental colitis. Because the balance of T cell subpopulations is critical for the balance of the mucosal immune system, this study explores the regulatory potency of HDAC inhibitors on T cell polarization as a mechanistic explanation for the observed anti-inflammatory effects. Although HDAC inhibition suppressed the polarization toward the pro-inflammatory T helper 17 (Th17) cells, it enhanced forkhead box P3 (FoxP3)(+) regulatory T cell polarization in vitro and in vivo at the site of inflammation in the lamina propria. This was paralleled by a down-regulation of the interleukin 6 receptor (IL-6R) on naïve CD4(+) T cells on the mRNA as well as on the protein level and changes in the chromatin acetylation at the IL6R gene and its promoter. Downstream of the IL-6R, HDAC inhibition was followed by a decrease in STAT3 phosphorylation as well as retinoic acid receptor-related orphan receptor γT (RORγT) expression, thus identifying the IL-6/STAT3/IL-17 pathway as an important target of HDAC inhibitors. These results directly translated to experimental colitis, where IL-6R expression was suppressed in naïve T cells, paralleled by a significant reduction of Th17 cells in the lamina propria of ITF2357-treated animals, resulting in the amelioration of disease. This study indicates that, in experimental colitis, inhibition of HDAC exerts an anti-inflammatory potency by directing T helper cell polarization via targeting the IL-6 pathway.

Antibody Response against SARS-CoV-2 after mRNA Vaccine in a Cohort of Hospital Healthy Workers Followed for 17 Months.

The assessment of antibody response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is of critical importance to verify the protective efficacy of available vaccines. Hospital healthcare workers play an essential role in the care and treatment of patients and were particularly at risk of contracting the SARS-CoV-2 infection during the pandemic. The vaccination protocol introduced in our hospital protected the workers and contributed to the containment of the infection' s spread and transmission, although a reduction in vaccine efficacy against symptomatic and breakthrough infections in vaccinated individuals was observed over time. Here, we present the results of a longitudinal and prospective analysis of the anti-SARS-CoV-2 antibodies at multiple time points over a 17-month period to determine how circulating antibody levels change over time following natural infection and vaccination for SARS-CoV-2 before (T0-T4) and after the spread of the omicron variant (T5-T6), analyzing the antibody response of 232 healthy workers at the Pio XI hospital in Desio. A General Estimating Equation model indicated a significant association of the antibody response with time intervals and hospital area, independent of age and sex. Specifically, a similar pattern of antibody response was observed between the surgery and administrative departments, and a different pattern with higher peaks of average antibody response was observed in the emergency and medical departments. Furthermore, using a logistic model, we found no differences in contracting SARS-CoV-2 after the third dose based on the hospital department. Finally, analysis of antibody distribution following the spread of the omicron variant, subdividing the cohort of positive individuals into centiles, highlighted a cut-off of 550 BAU/mL and showed that subjects with antibodies below this are more susceptible to infection than those with a concentration above the established cut-off value.

Preclinical studies in the mdx mouse model of duchenne muscular dystrophy with the histone deacetylase inhibitor givinostat.

Previous work has established the existence of dystrophin-nitric oxide (NO) signaling to histone deacetylases (HDACs) that is deregulated in dystrophic muscles. As such, pharmacological interventions that target HDACs (that is, HDAC inhibitors) are of potential therapeutic interest for the treatment of muscular dystrophies. In this study, we explored the effectiveness of long-term treatment with different doses of the HDAC inhibitor givinostat in mdx mice--the mouse model of Duchenne muscular dystrophy (DMD). This study identified an efficacy for recovering functional and histological parameters within a window between 5 and 10 mg/kg/d of givinostat, with evident reduction of the beneficial effects with 1 mg/kg/d dosage. The long-term (3.5 months) exposure of 1.5-month-old mdx mice to optimal concentrations of givinostat promoted the formation of muscles with increased cross-sectional area and reduced fibrotic scars and fatty infiltration, leading to an overall improvement of endurance performance in treadmill tests and increased membrane stability. Interestingly, a reduced inflammatory infiltrate was observed in muscles of mdx mice exposed to 5 and 10 mg/kg/d of givinostat. A parallel pharmacokinetic/pharmacodynamic analysis confirmed the relationship between the effective doses of givinostat and the drug distribution in muscles and blood of treated mice. These findings provide the preclinical basis for an immediate translation of givinostat into clinical studies with DMD patients.

Functional consequences of inhibiting exocytosis of Weibel-Palade bodies in acute renal ischemia.

Exocytosis of Weibel-Palade bodies (WPB) represents a distinct response of endothelial cells to stressors, and local release of WPB contents leads to systemic escalation of this response. We synthesized a glycine-(Nα-Et)lysine-proline-arginine (ITF 1697) peptide that has a potential to inhibit exocytosis of WPB and protect microcirculation. Here, we confirmed an inhibitory effect of ITF 1697 using intravital videoimaging and point-tracking of individual organelles. In an in vivo study, mice were implanted with Alzet osmotic pumps (10 µg ITF 1697·kg(-1)·min(-1) at volume of 1 µl/h) and subjected to renal ischemia (IRI). IRI resulted in marked renal injury and elevation of serum creatinine in mice treated with a vehicle. In contrast, renal injury and elevation of creatinine were significantly ameliorated in mice subjected to IRI and receiving ITF 1697. ITF 1697 prevented a systemic response to IRI: a significant surge in the levels of eotaxin and IL-8 (KC; both components of WPB), IL-1α, IL-1ß, and RANTES was all prevented or blunted by the administration of ITF 1697, whereas the levels of an anti-inflammatory, IL-10, and macrophage inflammatory protein-1α were upregulated in ITF 1697-treated animals. En face staining of aortic endothelial cells showed that WPB were depleted after 40-180 min post-IRI, and this was significantly blunted in aortic preparations obtained from mice treated with ITF 1697. WPB exocytosis contributed to IRI-associated mobilization of endothelial progenitor cells and hematopoietic stem cells, and ITF 1697 blunted their mobilization. Unexpectedly, 1 mo after IRI, mice treated with ITF 1697 showed a significantly more pronounced degree of scarring than nontreated animals. In conclusion, 1) application of ITF 1697 inhibits exocytosis of WPB and IRI; 2) the systemic inflammatory response of IRI is in part due to the exocytosis of WPB and its blockade blunts it; and 3) ITF 1697 improves short-term renal function after IRI, but not the long-term fibrotic complications.

Histone deacetylase inhibition modulates indoleamine 2,3-dioxygenase-dependent DC functions and regulates experimental graft-versus-host disease in mice.

Histone deacetylase (HDAC) inhibitors are antitumor agents that also have antiinflammatory properties. However, the mechanisms of their immunomodulatory functions are not known. We investigated the mechanisms of action of 2 HDAC inhibitors, suberoylanilide hydroxamic acid (SAHA) and ITF 2357, on mouse DC responses. Pretreatment of DCs with HDAC inhibitors significantly reduced TLR-induced secretion of proinflammatory cytokines, suppressed the expression of CD40 and CD80, and reduced the in vitro and in vivo allostimulatory responses induced by the DCs. In addition, injection of DCs treated ex vivo with HDAC inhibitors reduced experimental graft-versus-host disease (GVHD) in a murine allogeneic BM transplantation model. Exposure of DCs to HDAC inhibitors increased expression of indoleamine 2,3-dioxygenase (IDO), a suppressor of DC function. Blockade of IDO in WT DCs with siRNA and with DCs from IDO-deficient animals caused substantial reversal of HDAC inhibition-induced in vitro suppression of DC-stimulated responses. Direct injection of HDAC inhibitors early after allogeneic BM transplantation to chimeric animals whose BM-derived cells lacked IDO failed to protect from GVHD, demonstrating an in vivo functional role for IDO. Together, these data show that HDAC inhibitors regulate multiple DC functions through the induction of IDO and suggest that they may represent a novel class of agents to treat immune-mediated diseases.

Histone deacetylase inhibitors for treating a spectrum of diseases not related to cancer.

This issue of Molecular Medicine contains 14 original research reports and state-of-the-art reviews on histone deacetylase inhibitors (HDACi's), which are being studied in models of a broad range of diseases not related to the proapoptotic properties used to treat cancer. The spectrum of these diseases responsive to HDACi's is for the most part due to several antiinflammatory properties, often observed in vitro but importantly also in animal models. One unifying property is a reduction in cytokine production as well as inhibition of cytokine postreceptor signaling. Distinct from their use in cancer, the reduction in inflammation by HDACi's is consistently observed at low concentrations compared with the higher concentrations required for killing tumor cells. This characteristic makes HDACi's attractive candidates for treating chronic diseases, since low doses are well tolerated. For example, low oral doses of the HDACi givinostat have been used in children to reduce arthritis and are well tolerated. In addition to the antiinflammatory properties, HDACi's have shown promise in models of neurodegenerative disorders, and HDACi's also hold promise to drive HIV-1 out of latently infected cells. No one molecular mechanism accounts for the non-cancer-related properties of HDACi's, since there are 18 genes coding for histone deacetylases. Rather, there are mechanisms unique for the pathological process of specific cell types. In this overview, we summarize the preclinical data on HDACi's for therapy in a wide spectrum of diseases unrelated to the treatment of cancer. The data suggest the use of HDACi's in treating autoimmune as well as chronic inflammatory diseases.

Inhibition of HDAC activity by ITF2357 ameliorates joint inflammation and prevents cartilage and bone destruction in experimental arthritis.

Inhibition of histone deacetylases (HDAC) has been shown to modulate gene expression and cytokine production after stimulation with several stimuli. In the present study, the antiinflammatory effect of a potent HDACi, ITF2357, was explored in different experimental models of arthritis. In addition, the bone protective effect of ITF2357 was investigated in vitro. Treatment of acute arthritis (Streptococcus pyogenes cell wall [SCW] arthritis) with ITF2357 showed that joint swelling and cell influx into the joint cavity were reduced. Furthermore, the chondrocyte metabolic function was improved by treatment of ITF2357. The production of proinflammatory cytokines by synovial tissue was reduced after ITF2357 treatment. To examine the effect of HDAC inhibition on joint destruction, ITF2357 was applied to both rat adjuvant arthritis and mouse collagen type II arthritis. ITF2357 treatment both ameliorates the severity scores in arthritis models and prevents bone destruction. In an in vitro bone destruction assay, ITF2357 was highly effective at a dose of 100 nmol/L. In conclusion, inhibition of HDAC prevents joint inflammation and cartilage and bone destruction in experimental arthritis.

Pharmacokinetics, safety and inducible cytokine responses during a phase 1 trial of the oral histone deacetylase inhibitor ITF2357 (givinostat).

ITF2357 (givinostat) is a histone deacetylase inhibitor with antiinflammatory properties at low nanomolar concentrations. We report here a phase I safety and pharmacokinetics trial in healthy males administered 50, 100, 200, 400 or 600 mg orally. After 50 mg, mean maximal plasma concentrations reached 104 nmol/L 2 h after dosing, with a half-life of 6.9 h. After 100 mg, maximal concentration reached 199 nmol/L at 2.1 h with a half-life of 6.0 h. Repeat doses for 7 consecutive days of 50, 100 or 200 mg resulted in nearly the same kinetics. There were no serious adverse effects (AEs) and no organ toxicities. However, there was a dose-dependent but transient fall in platelets. After 7 daily doses of 50 or 100 mg, the mean decrease in platelets of 17 and 25% was not statistically significant and returned to baseline within 14 d. Blood removed from the subjects after oral dosing was cultured ex vivo with endotoxin, and the release of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-1Ra, interferon (IFN)-γ and IL-10 was determined. Maximal reduction in IL-1ß, TNFα, IL-6 and IFNγ was observed 4 h after dosing but returned to baseline at 12 h. There was no significant reduction in IL-1Ra or IL-10. With daily dosing, the fall in cytokine production in blood cultures observed on day 7 was nearly the same as that of the first day. We conclude that dosing of 50 or 100 mg ITF2357 is safe in healthy humans and transiently but repeatedly reduces the production of proinflammatory cytokines without affecting production of antiinflammatory cytokines.

The oral histone deacetylase inhibitor ITF2357 reduces cytokines and protects islet ß cells in vivo and in vitro.

In type 1 diabetes, inflammatory and immunocompetent cells enter the islet and produce proinflammatory cytokines such as interleukin-1ß (IL-1ß), IL-12, tumor necrosis factor-α (TNFα) and interferon-γ (IFNγ); each contribute to ß-cell destruction, mediated in part by nitric oxide. Inhibitors of histone deacetylases (HDAC) are used commonly in humans but also possess antiinflammatory and cytokine-suppressing properties. Here we show that oral administration of the HDAC inhibitor ITF2357 to mice normalized streptozotocin (STZ)-induced hyperglycemia at the clinically relevant doses of 1.25-2.5 mg/kg. Serum nitrite levels returned to nondiabetic values, islet function improved and glucose clearance increased from 14% (STZ) to 50% (STZ + ITF2357). In vitro, at 25 and 250 nmol/L, ITF2357 increased islet cell viability, enhanced insulin secretion, inhibited MIP-1α and MIP-2 release, reduced nitric oxide production and decreased apoptosis rates from 14.3% (vehicle) to 2.6% (ITF2357). Inducible nitric oxide synthase (iNOS) levels decreased in association with reduced islet-derived nitrite levels. In peritoneal macrophages and splenocytes, ITF2357 inhibited the production of nitrite, as well as that of TNFα and IFNγ at an IC(50) of 25-50 nmol/L. In the insulin-producing INS cells challenged with the combination of IL-1ß plus IFNγ, apoptosis was reduced by 50% (P < 0.01). Thus at clinically relevant doses, the orally active HDAC inhibitor ITF2357 favors ß-cell survival during inflammatory conditions.

Cutting edge: Negative regulation of dendritic cells through acetylation of the nonhistone protein STAT-3.

Histone deacetylase (HDAC) inhibition modulates dendritic cell (DC) functions and regulates experimental graft-vs-host disease and other immune-mediated diseases. The mechanisms by which HDAC inhibition modulates immune responses remain largely unknown. STAT-3 is a transcription factor shown to negatively regulate DC functions. In this study we report that HDAC inhibition acetylates and activates STAT-3, which regulates DCs by promoting the transcription of IDO. These findings demonstrate a novel functional role for posttranslational modification of STAT-3 through acetylation and provide mechanistic insights into HDAC inhibition-mediated immunoregulation by induction of IDO.

Pleiotropic anti-myeloma activity of ITF2357: inhibition of interleukin-6 receptor signaling and repression of miR-19a and miR-19b.

BACKGROUND: The histone deacetylase inhibitor ITF2357 has potent cytotoxic activity in multiple myeloma in vitro and has entered clinical trials for this disease. DESIGN AND METHODS: In order to gain an overall view of the activity of ITF2357 and identify specific pathways that may be modulated by the drug, we performed gene expression profiling of the KMS18 multiple myeloma cell line treated with the drug. The modulation of several genes and their biological consequence were verified in a panel of multiple myeloma cell lines and cells freshly isolated from patients by using polymerase chain reaction analysis and western blotting. RESULTS: Out of 38,500 human genes, we identified 140 and 574 up-regulated genes and 102 and 556 down-modulated genes at 2 and 6 h, respectively, with a significant presence of genes related to transcription regulation at 2 h and to cell cycling and apoptosis at 6 h. Several of the identified genes are particularly relevant to the biology of multiple myeloma and it was confirmed that ITF2357 also modulated their encoded proteins in different multiple myeloma cell lines. In particular, ITF2357 down-modulated the interleukin-6 receptor alpha (CD126) transcript and protein in both cell lines and freshly isolated patients' cells, whereas it did not significantly modify interleukin-6 receptor beta (CD130) expression. The decrease in CD126 expression was accompanied by decreased signaling by interleukin-6 receptor, as measured by STAT3 phosphorylation in the presence and absence of inter-leukin-6. Finally, the drug significantly down-modulated the MIRHG1 transcript and its associated microRNA, miR-19a and miR-19b, known to have oncogenic activity in multiple myeloma. CONCLUSIONS: ITF2357 inhibits several signaling pathways involved in myeloma cell growth and survival.

Histone deacetylase inhibitor ITF2357 is neuroprotective, improves functional recovery, and induces glial apoptosis following experimental traumatic brain injury.

Despite efforts aimed at developing novel therapeutics for traumatic brain injury (TBI), no specific pharmacological agent is currently clinically available. Here, we show that the pan-histone deacetylase (HDAC) inhibitor ITF2357, a compound shown to be safe and effective in humans, improves functional recovery and attenuates tissue damage when administered as late as 24 h postinjury. Using a well-characterized, clinically relevant mouse model of closed head injury (CHI), we demonstrate that a single dose of ITF2357 administered 24 h postinjury improves neurobehavioral recovery from d 6 up to 14 d postinjury (improved neurological score vs. vehicle; P< or =0.05), and that this functional benefit is accompanied by decreased neuronal degeneration, reduced lesion volume (22% reduction vs. vehicle; P< or =0.01), and is preceded by increased acetylated histone H3 levels and attenuation of injury-induced decreases in cytoprotective heat-shock protein 70 kDa and phosphorylated Akt. Moreover, reduced glial accumulation and activation were observed 3 d postinjury, and total p53 levels at the area of injury and caspase-3 immunoreactivity within microglia/macrophages at the trauma area were elevated, suggesting enhanced clearance of these cells via apoptosis following treatment. Hence, our findings underscore the relevance of HDAC inhibitors for ameliorating trauma-induced functional deficits and warrant consideration of applying ITF2357 for this indication.

Histone deacetylase (HDAC) inhibitors reduce the glial inflammatory response in vitro and in vivo.

Histone deacetylase inhibitors (HDACi) are emerging tools for epigenetic modulation of gene expression and suppress the inflammatory response in models of systemic immune activation. Yet, their effects within the brain are still controversial. Also, whether HDACs are expressed in astrocytes or microglia is unclear. Here, we report the identification of transcripts for HDAC 1-11 in cultured mouse glial cells. Two HDACi such as SAHA and ITF2357 induce dramatic increase of histone acetylation without causing cytotoxicity of cultured cells. Of note, the two compounds inhibit expression of pro-inflammatory mediators by LPS-challenged glial cultures, and potentiate immunosuppression triggered by dexamethasone in vitro. The anti-inflammatory effect is not due to HDACi-induced transcription of immunosuppressant proteins, (including SOCS-1/3) or microRNA-146. Rather, it is accompanied by direct alteration of transcription factor DNA binding and ensuing transcriptional activation. Indeed, both HDACi impair NFkappaB-dependent IkappaBalpha resynthesis in glial cells exposed to LPS, and, among various AP1 subunits and NFkappaB p65, affect the DNA binding activity of c-FOS, c-JUN and FRA2. Importantly, ITF2357 reduces the expression of pro-inflammatory mediators in the striatum of mice iontophoretically injected with LPS. Data demonstrate that mouse glial cells have ongoing HDAC activity, and its inhibition suppresses the neuroinflammatory response because of a direct impairment of the transcriptional machinery.

Level- and sport-specific Star Excursion Balance Test performance in female volleyball players.

BACKGROUND: Investigations of Star Excursion Balance Test (SEBT) performance differences between competition levels and sports are limited and results are inconsistent. The aim of the present study are: 1) to compare SEBT performance between elite and semi-professional female volleyball players; 2) to evaluate differences in SEBT scores between positions (Hitters, Middle Blockers, Setters, and Liberoes); and 3) to compare dynamic balance characteristics between professional female Italian volleyball players with NCAA Division I female athletes practicing six different sports (hockey, football, basketball, golf, softball, and volleyball). For the latter comparison, previously published data obtained from a study were used. METHODS: Fifty-one female volleyball players were grouped in two groups, elite athletes (EG; N.=27) and semi-professional players (SG; N.=24), and further categorized into hitters, middle blockers, setters, and liberos. Anterior (A), posteromedial (PM), and posterolateral (PL) distances, and composite score (COMP) of SEBT short form were studied. COMP was calculated as the average of the normalized distances across the three directions. RESULTS: Significant differences were observed for the A (right, P=0.014 and left, P=0.011), PL (right, P=0.017 and left, P=0.008), PM (P<0.001) directions, and COMP scores (right, P=0.008 and left, P=0.009), with higher normalized distances noted for the EG and no differences between different positions. COMP scores were lower for the EG than the NCAA Division I female hockey (P<0.001) and football players (P=0.031) but similar to those of basketball, golf, softball, and volleyball players. CONCLUSIONS: The EG scored higher on dynamic postural-control tasks than the SG. SEBT performance varied significantly between sports. Clinicians and strength coaches need to be aware of sport specific differences in dynamic postural control measurements in both rehabilitation and athletic development.

Histone deacetylase inhibitor ITF2357 (givinostat) reverts transformed phenotype and counteracts stemness in in vitro and in vivo models of human glioblastoma.

PURPOSE: Aberrant expression and activity of histone deacetylases (HDACs) sustain glioblastoma (GBM) onset and progression, and, therefore, HDAC inhibitors (HDACi) represent a promising class of anti-tumor agents. Here, we analyzed the effects of ITF2357 (givinostat), a pan-HDACi, in GBM models for its anti-neoplastic potential. METHODS: A set of GBM- and patient-derived GBM stem-cell lines was used and the ITF2357 effects on GBM oncophenotype were investigated in in vitro and in vivo xenograft models. RESULTS: ITF2357 inhibited HDAC activity and affected GBM cellular fate in a dose-dependent manner by inducing G1/S growth arrest (1-2.5 µM) or caspase-mediated cell death (≥ 2.5 µM). Chronic treatment with low doses (≤ 1 µM) induced autophagy-mediated cell death, neuronal-like phenotype, and the expression of differentiation markers, such as glial fibrillar actin protein (GFAP) and neuron-specific class III beta-tubulin (Tuj-1); this reduces neurosphere formation from patient-derived GBM stem cells. Autophagy inhibition counteracted the ITF2357-induced expression of differentiation markers in p53-expressing GBM cells. Finally, in in vivo experiments, ITF2357 efficiently passed the blood-brain barrier, so rapidly reaching high concentration in the brain tissues, and significantly affected U87MG and U251MG growth in orthotopic xenotransplanted mice. CONCLUSIONS: The present findings provide evidence of the key role played by HDACs in sustaining transformed and stem phenotype of GBM and strongly suggest that ITF2357 may have a clinical potential for the HDACi-based therapeutic strategies against GBM.

Correction to: Histone deacetylase inhibitor ITF2357 (givinostat) reverts transformed phenotype and counteracts stemness in in vitro and in vivo models of human glioblastoma.

In the original publication, the 6th author's first name and the last name was inverted and incorrectly published. The correct author name is Letizia Ferella.