Primary HIV infection features colonic damage and neutrophil inflammation yet containment of microbial translocation.

INTRODUCTION: Impairment of the gastrointestinal barrier leads to microbial translocation and peripheral immune activation, which are linked to disease progression. Data in the setting of primary HIV/SIV infection suggest that gut barrier damage is one of the first events of the pathogenic cascade, preceding mucosal immune dysfunction and microbial translocation. We assessed gut structure and immunity as well as microbial translocation in acutely and chronically-infected, combination antiretroviral therapy (cART)-naive individuals. METHODS: Fifteen people with primary HIV infection (P-HIV) and 13 with chronic HIV infection (C-HIV) c-ART-naive participants were cross-sectionally studied. Gut biopsies were analysed in terms of gut reservoirs (total, integrated and unintegrated HIV DNA); tight junction proteins (E-cadherin, Zonula Occludens-1), CD4 + expression, neutrophil myeloperoxidase (histochemical staining); collagen deposition (Masson staining). Flow cytometry was used to assess γδ T-cell frequency (CD3 + panγδ+Vδ1+/Vδ2+). In plasma, we measured microbial translocation (LPS, sCD14, EndoCAb) and gut barrier function (I-FABP) markers (ELISA). RESULTS: P-HIV displayed significantly higher tissue HIV DNA, yet neutrophil infiltration and collagen deposition in the gut were similar in the two groups. In contrast, microbial translocation markers were significantly lower in P-HIV compared with C-HIV. A trend to higher mucosal E-cadherin, and gut γδ T-cells was also observed in P-HIV. CONCLUSION: Early HIV infection features higher HIV DNA in the gut, yet comparable mucosal alterations to those observed in chronic infection. In contrast, microbial translocation is contained in primary HIV infection, likely because of a partial preservation of E-cadherin and mucosal immune subsets, namely γδ T-cells.

Effects of Multidisciplinary Rehabilitation Enhanced with Neuropsychological Treatment on Post-Acute SARS-CoV-2 Cognitive Impairment (Brain Fog): An Observational Study.

Concentration and memory impairment (named "brain fog") represents a frequent and disabling neuropsychological sequela in post-acute COVID-19 syndrome (PACS) patients. The aim of this study was to assess whether neurocognitive function could improve after a multidisciplinary rehabilitation program enhanced with individualized neuropsychological treatment. A prospective monocentric registry of PACS patients consecutively admitted to our Rehabilitation Unit was created. The Montreal Cognitive Assessment (MoCA) was used to assess cognitive impairment at admission and discharge. A total of sixty-four (64) PACS patients, fifty-six (56) of them with brain fog, were treated with a day-by-day individualized psychological intervention of cognitive stimulation (45 min) on top of a standard in-hospital rehabilitation program. The mean duration of the acute-phase hospitalization was 55.8 ± 25.8 days and the mean in-hospital rehabilitation duration was 30 ± 10 days. The mean age of the patients was 67.3 ± 10.4 years, 66% of them were male, none had a previous diagnosis of dementia, and 66% of the entire sample had experienced severe COVID-19. At admission, only 12% of the patients had normal cognitive function, while 57% showed mild, 28% moderate, and 3% severe cognitive impairment. After psychological treatment, a significant improvement in the MoCA score was found (20.4 ± 5 vs. 24.7 ± 3.7; p < 0.0001) as a result of significant amelioration in the following domains: attention task (p = 0.014), abstract reasoning (p = 0.003), language repetition (p = 0.002), memory recall (p < 0.0001), orientation (p < 0.0001), and visuospatial abilities (p < 0.0001). Moreover, the improvement remained significant after multivariate analysis adjusted for several confounding factors. Finally, at discharge, 43% of the patients with cognitive impairment normalized their cognitive function, while 4.7% were discharged with residual moderate cognitive impairment. In conclusion, our study provides evidence of the effects of multidisciplinary rehabilitation enhanced with neuropsychological treatment on improvement in the cognitive function of post-acute COVID-19 patients.

Motor imagery and action-observation in neurorehabilitation: A study protocol in Parkinson's disease patients.

Introduction: Action Observation Treatment (AOT) and Motor Imagery (MI) represent very promising cognitive strategies in neuro-rehabilitation. This study aims to compare the effectiveness of the two cognitive strategies, taken alone or combined, in Parkinson's disease patients. Material and methods: This study is designed as a prospective randomized controlled trial, with four arms. We estimated a sample size of 64 patients (16 in each treatment group) to be able to detect an effect size of F = 0.4 with a statistical significance of 0.05. Primary outcomes will be functional gains in the FIM and UPDRS scales. Secondary outcome measure will be functional gain as revealed by kinematic parameters measured at Gait Analysis. Discussion: The results of this trial will provide insights into the use of AOT and MI, taken alone or combined, in the rehabilitation of Parkinson's disease patients. Ethics and dissemination: The study protocol was approved by the Ethics Committee of the Don Gnocchi Foundation. The study will be conducted in accordance with the 1996 World Medical Association guidelines and according to good clinical practice. The study has been registered on clinicaltrial.gov under the following code: AOTPRFDG. Dissemination will include both submission of the study to peer-reviewed journals and discussion of the study protocol at conferences.

Combining Action Observation Treatment with a Brain-Computer Interface System: Perspectives on Neurorehabilitation.

Action observation treatment (AOT) exploits a neurophysiological mechanism, matching an observed action on the neural substrates where that action is motorically represented. This mechanism is also known as mirror mechanism. In a typical AOT session, one can distinguish an observation phase and an execution phase. During the observation phase, the patient observes a daily action and soon after, during the execution phase, he/she is asked to perform the observed action at the best of his/her ability. Indeed, the execution phase may sometimes be difficult for those patients where motor impairment is severe. Although, in the current practice, the physiotherapist does not intervene on the quality of the execution phase, here, we propose a stimulation system based on neurophysiological parameters. This perspective article focuses on the possibility to combine AOT with a brain-computer interface system (BCI) that stimulates upper limb muscles, thus facilitating the execution of actions during a rehabilitation session. Combining a rehabilitation tool that is well-grounded in neurophysiology with a stimulation system, such as the one proposed, may improve the efficacy of AOT in the treatment of severe neurological patients, including stroke patients, Parkinson's disease patients, and children with cerebral palsy.

Endothelial-Mesenchymal Transition in COVID-19 lung lesions.

Sars-Cov-2 infection is still a healthcare emergency and acute respiratory distress failure with Diffuse Alveolar Damage (DAD) features is the main causes of patients' death. Pathogenic mechanisms of the disease are not clear yet, but new insights are necessary to improve therapeutic management, to prevent fatal irreversible multi-organ damage and to adequately follow up those patients who survive. Here we investigated, by histochemistry and immunohistochemistry, a wide number of mapped lung specimens taken from whole body autopsies of 7 patients dead of COVID-19 disease. Our data confirm morphological data of other authors, and enlarge recent reports of the literature suggesting that Endothelial-Mesenchymal Transition might be central to COVID-19 lung fibrosing lesions. Furthermore, based upon recent acquisition of new roles in immunity and vascular pathology of the CD31 molecule, we hypothesize that this molecule might be important in the development and treatment of COVID-19 pulmonary lesions. These preliminary findings need further investigations to shed light on the complexity of Sars-Cov-2 disease.

M1 and M2 macrophages' clinicopathological significance in cutaneous melanoma.

Skin malignant melanoma (MM) is an aggressive cancer with an increasing incidence with limited therapies in advanced stages. Tumor-associated macrophages (TAMs) are the major immune constituent of the MM microenvironment and contribute toward its prognosis. TAMs' characterization and localization in human cancer is important to understand cancer progression and to identify molecular personalized therapies. M2 TAMs in stage I-II MMs are associated with worse prognostic parameters. A comprehensive M1-macrophage and M2-macrophage intratumoral localization and quantification in all stages of skin MMs is documented here with its clinical significance. To highlight immune pathways and possible early indicators of MM progression, we evaluated the number of M1 and M2 TAMs and intratumoral distribution in a large series of skin MMs. CD68 double immunostaining with MRP8-14 or inducible nitric oxide synthase (M1 macrophages) and with CD163 or CD204 (M2 macrophages) was performed in 94 stage I-IV skin MMs with a long duration of follow-up. The accumulation and distribution of M1 and M2 TAMs in intratumoral nests, stroma, and at the invasive front was correlated with clinicopathological variables. Since the early stage of MMs, M1 intratumoral macrophages were fewer than the M2 population; their recruitment was rapidly and progressively overwhelmed by an increase in M2 TAMs during MM progression. Independent of their intratumoral distribution, the accumulation of both M1 and M2 TAMs is associated with poor prognostic indicators and patients' survival. M1-recruited macrophages shift to the M2 phenotype early in MM development, possibly induced by high inducible nitric oxide synthase intratumoral increase peculiarly occurring since the initial MM stages. M2-recruited TAMs overwhelm M1 accumulation in all stages of MM progression, thus favoring neoplastic growth and dissemination. Independent of their intratumoral distribution, the prevalent accumulation of M2 TAMs in MM is statistically confirmed to be a poor indicator of patients' outcome and a potential target of immune therapies.

Regulatory landscape of AGE-RAGE-oxidative stress axis and its modulation by PPARγ activation in high fructose diet-induced metabolic syndrome.

BACKGROUND: The AGE-RAGE-oxidative stress (AROS) axis is involved in the onset and progression of metabolic syndrome induced by a high-fructose diet (HFD). PPARγ activation is known to modulate metabolic syndrome; however a systems-level investigation looking at the protective effects of PPARγ activation as related to the AROS axis has not been performed. The aim of this work is to simultaneously characterize multiple molecular parameters within the AROS axis, using samples taken from different body fluids and tissues of a rat model of HFD-induced metabolic syndrome, in the presence or absence of a PPARγ agonist, Rosiglitazone (RGZ). METHODS: Rats were fed with 60% HFD for the first half of the treatment duration (21 days) then continued with either HFD alone or HFD plus RGZ for the second half. RESULTS: Rats receiving HFD alone showed metabolic syndrome manifestations including hypertension, dyslipidemia, increased glucose levels and insulin resistance, as well as abnormal kidney and inflammatory parameters. Systolic blood pressure, plasma triglyceride and glucose levels, plasma creatinine, and albuminuria were significantly improved in the presence of RGZ. The following molecular parameters of the AROS axis were significantly upregulated in our rat model: carboxymethyl lysine (CML) in urine and liver; carboxyethyl lysine (CEL) in urine; advanced glycation end products (AGEs) in plasma; receptor for advanced glycation end products (RAGE) in liver and kidney; advanced oxidation protein products (AOPP) in plasma; and 4-hydroxynonenal (HNE) in plasma, liver, and kidney. Conversely, with RGZ administration, the upregulation of AOPP and AGEs in plasma, CML and CEL in urine, RAGE in liver as well as HNE in plasma and liver was significantly counteracted/prevented. CONCLUSIONS: Our data demonstrate (i) the systems-level regulatory landscape of HFD-induced metabolic syndrome involving multiple molecular parameters, including HNE, AGEs and their receptor RAGE, and (ii) attenuation of metabolic syndrome by PPARγ modulation.

Osteonectin (SPARC) Expression in Vascular Calcification: In Vitro and Ex Vivo Studies.

Osteonectin, also termed SPARC, is a noncollagenous protein of bone matrix. Since there are controversial results regarding its role during the process of vascular calcification, we investigated osteonectin expression in our in vitro calcification model. Rat vascular smooth muscle cells (VSMCs) were challenged with high phosphate (5 mmol/L Pi) and analyzed quantifying calcium levels, through immunohistochemical studies, and studying gene expression. We detected a peak of osteonectin expression at day 7 in cell treated with high phosphate. The time course of calcium deposition, reflected the expression of osteonectin, resulting extensively present at day 7. On the contrary, the expression of the mitotic marker Ki-67 had a peak at day 4, showing no correlation between osteonectin and cell proliferation. Moreover, 7 days was the time point in which Cbfα1/RUNX-2 had its maximal expression. Furthermore, ascorbic acid increased osteonectin expression, supporting a procalcifying role for this protein. Next we decided to study osteonectin expression ex vivo in fetal, adult not calcified, and adult calcific vessels. Immunohistochemical studies demonstrated a spread and strong reactivity in VSMCs of a 20-week fetus, confirming that osteonectin may have a potential role in regulation of mitosis and in cell differentiation. In adult not calcified arteries, osteonectin was constitutively expressed and its levels increased in atherosclerotic and in calcified plaques, where it could have a regulatory role in the calcification process. Our in vitro and ex vivo data show osteonectin expression during the calcification process and suggest its potential role as procalcifying factor.

Impaired gut junctional complexes feature late-treated individuals with suboptimal CD4+ T-cell recovery upon virologically suppressive combination antiretroviral therapy.

OBJECTIVE: HIV-infected individuals with incomplete CD4⁺ T-cell recovery upon combination antiretroviral therapy (cART) display high levels of immune activation and microbial translocation. However, whether a link exists between gut damage and poor immunological reconstitution remains unknown. DESIGN: Cross-sectional study of the gastrointestinal tract in late cART-treated HIV-infected individuals: 15 immunological nonresponders (CD4⁺ <350 cells/µl and/or delta CD4⁺ change from baseline <30%); 15 full responders (CD4⁺ >350 cells/µl and/or delta CD4⁺ change from baseline >30%). METHODS: We assessed gut structure (junctional complex proteins in ileum and colon) and function (small intestine permeability/damage and microbial translocation parameters). The composition of the fecal microbiome and the size of the HIV reservoir in the gut and peripheral blood were investigated as possible mechanisms underlying mucosal impairment. RESULTS: Markers of intestinal permeability, damage, systemic inflammation, and microbial translocation were comparable in all study individuals, yet the expression of junctional complex proteins in gut biopsies was significantly lower in HIV-infected patients with incomplete CD4⁺ restoration and negatively correlated with markers of CD4⁺ reconstitution. Electron microscopy revealed dilated intercellular spaces in individuals lacking immunological response to cART, yet not in patients displaying CD4⁺ T-cell recovery. Analysis of the fecal microbiome revealed an overall outgrowth of Bacteroides-Prevotella spp. with no differences according to CD4⁺ T-cell reconstitution. Interestingly, HIV reservoirs in peripheral CD4⁺ T cells and intestinal tissue negatively correlated with immune recovery. CONCLUSION: These observations establish gut damage and the size of the HIV reservoir as features of deficient immunological response to cART and provide new elements for interventional strategies in this setting.

Epigenetic effects of chromatin remodeling agents on organotypic cultures.

BACKGROUND: Tumor epigenetic defects are of increasing relevance to clinical practice, because they are 'druggable' targets for cancer therapy using chromatin-remodeling agents (CRAs). New evidences highlight the importance of the microenvironment on the epigenome regulation and the need to use culture models able to preserve tissue morphology, to better understand the action of CRAs. Methods & methods: We studied the epigenetic response induced by culturing and CRAs in a preclinical model, preserving ex vivo the original tissue microenvironment and morphology, assessing different epigenetic signatures. Our overall findings suggest that culturing and CRAs cause heterogeneous effects on the genes methylation; CRAs affect the global DNA methylation and can trigger an active DNA demethylation; the culture induces alterations in the histone deacetylase expression. CONCLUSION: Despite the limited number of cases, these findings can be considered a proof of concept of the possibility to test CRAs epigenetic effects on ex vivo tissues maintained in their native tissue architecture.

Discrepancies between bone marrow histopathology and clinical phenotype in BCR-ABL1-negative myeloproliferative neoplasms associated with splanchnic vein thrombosis.

We examined a consecutive series of 29 patients with myeloproliferative neoplasms (MPNs) associated with splanchnic vein thrombosis (SVT) in order to evaluate their bone marrow morphology and identify possible associations between histological findings and clinical features. Eleven patients showed the morphological features of polycythemia vera (PV), 11 of primary myelofibrosis (PMF) and six of essential thrombocythemia (ET). Molecular analyses identified the JAK2 V617F mutation in 27 patients; one of the JAK2-negative patients carried the MPL W515K mutation, the other was "triple-negative" (no JAK2, MPL or CALR mutation). On the basis of the WHO classification, three patients were classified as having PV, 11 as having PMF, and two as having ET; the remaining 13 cases fell into the MPN-unclassifiable category as there were discrepancies between their morphological and clinical features. In conclusion, our findings suggest that bone marrow histology should always be considered a key component of the diagnostic algorithm in patients with SVT, but that it is not enough to distinguish the different entities. This is particularly important because diagnoses of PV, PMF or ET have very different prognoses and obviously imply different therapies. It is therefore necessary to adopt a comprehensive approach that considers morphological, clinical and molecular data.

PDGFB hypomethylation is a favourable prognostic biomarker in primary myelofibrosis.

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterised by the clonal proliferation of the haematopoietic precursors together with the progressive development of bone marrow fibrosis. This stromal alteration is an important clinical issue and specific prognostic markers are not currently available. In bone marrow biopsies from 58 PMF patients, we explored the methylation pattern of genes encoding cytokines involved in the stromal reaction, namely platelet-derived growth factor-beta (PDGFB), transforming growth factor-beta (TGFB) and basic fibroblast growth factor (FGF2). We also evaluated the methylation profile of the Long Interspersed Nucleotide Element 1 (LINE-1). PDGFB, FGF2 and LINE-1, but not TGFB, were significantly differently methylated in PMF compared to controls. Significantly, PDGFB hypomethylation (<16%) was correlated with a favourable PMF prognosis (grade of marrow fibrosis, p=0.03; International Prognostic Scoring Systems p=0.01 and Dynamic International Prognostic Scoring Systems, p=0.02). Although the basis of the association of PDGFB hypomethylation with favourable prognosis remains to be clarified, we speculate that hypomethylation in PMF could represent the effect of acquired somatic mutations in genes involved in epigenetic regulation of the genome.

MicroRNA as potential biomarker in HCV-associated diffuse large B-cell lymphoma.

AIMS: To identify molecular characteristics to hepatitis C virus (HCV)-associated diffuse large B-cell lymphoma (DLBCL) through a comprehensive miRNAs expression profiling. METHODS: In this study, miRNA profiles were obtained from 37 patients with DLBCLs and 60 patients with reactive lymph nodes, equally distributed according to HCV presence. Germinal centres, from reactive lymph nodes were used as controls. Clinical features at presentation were available for all patients. RESULTS: A set of 52 miRNAs define a signature for HCV-associated DLBCL. Importantly, decreased expression of miR-138-5p and increased expression of miR-147a, miR-147b and miR-511-5p in HCV DLBCL was found to be a poor prognostic factor for HCV-positive DLBCL patients. CONCLUSIONS: These data reveal molecular differences in diffuse DLBCL patients according to HCV presence, potentially useful as novel prognostic or therapeutic biomarkers.

miR-296/Scribble axis is deregulated in human breast cancer and miR-296 restoration reduces tumour growth in vivo.

miR-296-5p is a central regulator of signalling pathways affecting development, stem cell differentiation and cancer. We hypothesized that miR-296-5p is involved in breast cancer onset and progression possibly through regulation of its target SCRIB (Scribble), a polarity protein recently implicated in the acquisition of cancer stem cell traits and in cell motility. We found that miR-296-5p levels were consistently reduced in human breast cancer tissues compared with non-neoplastic mammary parenchyma, and low expression of this miRNA predicted shorter disease-free survival independently of classic clinicopathological parameters. Further, reduced miR-296-5p levels were significantly correlated with an earlier spread of cancer in the overall series and with distant metastases in the subset. In contrast with its regulator, SCRIB was overexpressed and mislocalized in primary breast cancers or locoregional or distant metastatic lesions compared with normal parenchyma. Notably, SCRIB mislocalization was associated with overall survival, metastatic spread and organ tropism in patients with breast cancer. Finally, direct injection of a precursor miR-296-5p into tumours of a breast cancer xenograft model significantly decreased tumour growth. Our results show that the miR-296-5p/SCRIB axis plays a role in breast carcinogenesis and an miR-296-5p-based therapeutic approach hampers breast cancer tumour growth in vivo. Modulation of miR-296-5p may represent a new therapeutic option for patients with breast cancer.

High levels of vascular endothelial growth factor protein expression are associated with an increased risk of transfusion dependence in myelodysplastic syndromes.

We evaluated the prognostic significance of vascular endothelial growth factor (VEGF) protein expression in 79 bone marrow biopsy specimens of patients with myelodysplastic syndromes (MDS). VEGF levels normalized for bone marrow cellularity (VEGF index [VEGFi]) were higher in the World Health Organization (WHO) classification-based prognostic scoring system (WPSS) "very high risk" than in the "very low risk" group (P = .009) and in patients with MDS with a poor karyotype than in the other cytogenetic risk groups (P = .015). High VEGFi (>75(th) percentile) predicted transfusion dependence (adjusted odds ratio, 10.38; 95% confidence interval, 1.02-106), and were correlated with leukemia-free survival and overall survival. The inclusion of VEGFi in the International Prognostic Scoring System and WPSS maintained its significant prognostic role in predicting leukemia-free and overall survival; it also seemed to improve the discrimination of the different prognostic classes, especially WPSS low-risk classes. Our findings support the clinical relevance of VEGFi expression in the bone marrow biopsy specimens of patients with MDS.

The European Consensus on grading of bone marrow fibrosis allows a better prognostication of patients with primary myelofibrosis.

We investigated the relationship between the International Prognostic Scoring System of the International Working Group for Myelofibrosis Research and Treatment and the European Consensus on grading of bone marrow fibrosis (MF) in patients with primary myelofibrosis. We compared them in 196 consecutive primary myelofibrosis patients (median follow-up 45.7 months; range 7.4-159). International Prognostic Scoring System classified 42 cases as low risk, 73 as intermediate risk-1, 69 as intermediate risk-2, and 12 as high risk; European Consensus on grading of bone marrow fibrosis classified 83 cases as MF-0, 58 as MF-1, 41 as MF-2, and 14 as MF-3. By the time of the analysis, 30 patients (15.3%) had died. Overall median survival was 3.8 years (95% confidence interval: 3.3-4.3). Multivariate analysis confirmed that both scoring systems independently predicted survival, with hazard ratios similar to those provided by univariate analysis (respectively, 2.40 (95% confidence interval: 1.47-3.91) and 2.58 (95% confidence interval: 1.72-3.89) but the likelihood ratio increased from 19.6 of the International Prognostic Scoring System or 29.0 of the European Consensus on grading of bone MF to 42.3 when both measures were considered together. Analysis of the overall survival curves documented that patients classified as having the most favourable rate with both prognostic scores (ie low risk and MF-0) survive longer than those with only one favourable score (ie low risk but MF >0 or MF-0, but International Prognostic Scoring System >low risk). In contrast, those patients classified as having the most unfavourable rate for both scores (high risk and MF-3) have a shorter survival than those with only one unfavourable score (ie high risk but MF<3 or MF-3, but International Prognostic Scoring System

Increased expression of vascular endothelial growth factor receptor 1 correlates with VEGF and microvessel density in Philadelphia chromosome-negative myeloproliferative neoplasms.

AIMS: The authors investigated vascular endothelial growth factor receptor 1 (VEGFR-1) protein expression in a series of Philadelphia chromosome-negative myeloproliferative neoplasms (Ph- MPNs) and its correlations with microvessel density (MVD) and vascular endothelial growth factor (VEGF). METHODS: 83 bone marrow biopsies of Ph- MPNs patients, including 27 essential thrombocythaemia (ET), 21 polycythaemia vera (PV) and 35 primary myelofibrosis (PMF), and 10 normal controls (NCs) were investigated by immunohistochemistry. RESULTS: Patients with PV and PMF showed an increased MVD (PV: 20.1±10.6; PMF: 25.8±6.5) compared with those with ET or NCs (ET: 10.4±4.6; NCs: 7±3.4). VEGFR-1 expression was increased in Ph- MPNs, particularly in PV and PMF (NCs: 0.07±0.03; ET: 0.15±0.09; PV: 0.31±0.2; PMF: 0.31±0.04). VEGF expression parallelled VEGFR-1 and resulted increased in Ph- MPNs (NCs: 0.08±0.04; ET: 0.13±0.06; PV: 0.29±0.2; PMF: 0.31±0.15) and higher in post-polycythaemic myelofibrosis and in the fibrotic stage of PMF than in the non-fibrotic phases of both diseases. VEGFR-1 protein expression correlated with MVD and VEGF expression in Ph- MPNs. VEGFR-1 and VEGF were expressed by the same bone marrow populations: megakaryocytes, macrophages and immature myeloid precursors showed a moderate to strong immunostaining intensity in both Ph- MPNs and NCs. The erythroid precursors were not immunoreactive. CONCLUSIONS: VEGFR-1 and VEGF were increased and co-localised in megakaryocytes, macrophages and myeloid precursors of Ph- MPNs. This finding supports the hypothesis of a VEGF/VEGFR-1 autocrine loop in the neoplastic cells of Ph- MPNs.

The carbonyl scavenger carnosine ameliorates dyslipidaemia and renal function in Zucker obese rats.

The metabolic syndrome is a risk factor that increases the risk for development of renal and vascular complications. This study addresses the effects of chronic administration of the endogenous dipeptide carnosine (ß-alanyl-L-histidine, L-CAR) and of its enantiomer (ß-alanyl-D-histidine, D-CAR) on hyperlipidaemia, hypertension, advanced glycation end products, advanced lipoxidation end products formation and development of nephropathy in the non-diabetic, Zucker obese rat. The Zucker rats received a daily dose of L-CAR or D-CAR (30 mg/kg in drinking water) for 24 weeks. Systolic blood pressure was recorded monthly. At the end of the treatment, plasma levels of triglycerides, total cholesterol, glucose, insulin, creatinine and urinary levels of total protein, albumin and creatinine were measured. Several indices of oxidative/carbonyl stress were also measured in plasma, urine and renal tissue. We found that both L- and D-CAR greatly reduced obese-related diseases in obese Zucker rat, by significantly restraining the development of dyslipidaemia, hypertension and renal injury, as demonstrated by both urinary parameters and electron microscopy examinations of renal tissue. Because the protective effect elicited by L- and D-CAR was almost superimposable, we conclude that the pharmacological action of L-CAR is not due to a pro-histaminic effect (D-CAR is not a precursor of histidine, since it is stable to peptidic hydrolysis), and prompted us to propose that some of the biological effects can be mediated by a direct carbonyl quenching mechanism.

Oxidative stress is increased in primary and post-polycythemia vera myelofibrosis.

OBJECTIVE: To determine if increased cell turnover in chronic myeloproliferative disorders can lead to hyperhomocysteinemia as a result of folate and/or cobalamin depletion, and contribute to oxidative stress. MATERIALS AND METHODS: The clinical role of oxidative stress was investigated by measuring reactive oxygen species (ROS), total antioxidant capacity (TAC), and total homocysteine (tHcy), folate, cobalamin, and holotranscobalamin (HoloTC) levels in 51 chronic myeloproliferative disorders patients (male-to-female ratio: 1.1; median age: 64 years; range, 40-84 years), including 42 with primary myelofibrosis and 9 with post-polycythemia vera myelofibrosis. RESULTS: Myelofibrotic patients had higher tHcy (p = 0.0201) and an unbalanced oxidative status (higher ROS and lower TAC levels; p < 0.0001) than controls. Presence of diabetes or another neoplasia was associated with higher ROS levels (p < 0.05), splenomegaly, hepatomegaly, and peripheral blasts with lower HoloTC levels (p < 0.005). The most severe forms of myelofibrosis (2-3) were associated with lower TAC (p = 0.045) and HoloTC levels (p = 0.017). Patients with Janus kinase-2 mutations had lower HoloTC levels (p = 0.0059). HoloTC deficiency was more frequently associated with Janus kinase-2 homozygosity (p < 0.0003). CONCLUSIONS: Our findings suggest that the determination of HoloTC, tHcy, ROS concentrations, and TAC, can identify latent cobalamin deficiency and provide a rational basis for correcting the increased oxidation associated with disease progression.

VEGF expression correlates with microvessel density in Philadelphia chromosome-negative chronic myeloproliferative disorders.

We examined microvessel density (MVD) and immunohistochemical expression of vascular endothelial growth factor (VEGF) in the bone marrow biopsy specimens of 98 patients with Philadelphia chromosome-negative (Ph-) chronic myeloproliferative disorders (CMPDs). There were significantly more MVD "hot spots" in chronic idiopathic myelofibrosis (CIMF; mean +/- SD, 25.6 +/- 6.3) and polycythemia vera (PV; 20.7 +/- 10.2) cases than in essential thrombocythemia (ET) cases (10.1 +/- 4.5) and normal control (NC) samples (7.5 +/- 3.6) (P < .05). Similar results were found using a semiquantitative method (P < .0001). A calculated VEGF index (VEGF(i)) was higher in CIMF (0.29 +/- 0.15) and PV (0.28 +/- 0.20) cases than in ET (0.12 +/- 0.05) and NC (0.08 +/- 0.04) cases (P < .0001). MVD and VEGF(i) were higher in the myelofibrotic phases of CIMF and PV. There was a direct correlation between VEGF(i) and MVD when considering the Ph- CMPDs together (r = 0.67; P < .001) and when considering PV (r = 0.79; P < .001) and CIMF (r = 0.40; P = .013) as individual entities. Our data could provide a rationale for directly targeting VEGF or endothelial cells in CIMF and PV.