Free-amino acid metabolic profiling of visceral adipose tissue from obese subjects.

Interest in adipose tissue pathophysiology and biochemistry have expanded considerably in the past two decades due to the ever increasing and alarming rates of global obesity and its critical outcome defined as metabolic syndrome (MS). This obesity-linked systemic dysfunction generates high risk factors of developing perilous diseases like type 2 diabetes, cardiovascular disease or cancer. Amino acids could play a crucial role in the pathophysiology of the MS onset. Focus of this study was to fully characterize amino acids metabolome modulations in visceral adipose tissues (VAT) from three adult cohorts: (i) obese patients (BMI 43-48) with metabolic syndrome (PO), (ii) obese subjects metabolically well (O), and (iii) non obese individuals (H). 128 metabolites identified as 20 protein amino acids, 85 related compounds and 13 dipeptides were measured by ultrahigh performance liquid chromatography-tandem mass spectroscopy (UPLC-MS/MS) and gas chromatography-/mass spectrometry GC/MS, in visceral fat samples from a total of 53 patients. Our analysis indicates a probable enhanced BCAA (leucine, isoleucine, valine) degradation in both VAT from O and PO subjects, while levels of their oxidation products are increased. Also PO and O VAT samples were characterized by: elevated levels of kynurenine, a catabolic product of tryptophan and precursor of diabetogenic substances, a significant increase of cysteine sulfinic acid levels, a decrease of 1-methylhistidine, and an up regulating trend of 3-methylhistidine levels. We hope this profiling can aid in novel clinical strategies development against the progression from obesity to metabolic syndrome.

Increased endothelin-1-mediated vasoconstrictor tone in human obesity: effects of gut hormones.

The heavy impact of obesity on the development and progression of cardiovascular disease has sparked sustained efforts to uncover the mechanisms linking excess adiposity to vascular dysfunction. Impaired vasodilator reactivity has been recognized as an early hemodynamic abnormality in obese patients, but also increased vasoconstrictor tone importantly contributes to their vascular damage. In particular, upregulation of the endothelin (ET)-1 system, consistently reported in these patients, might accelerate atherosclerosis and its complication, given the pro-inflammatory and mitogenic properties of ET-1. In recent years, a number of gut hormones, in addition to their role as modulators of food intake, energy balance, glucose and lipid metabolism, and insulin secretion and action, have demonstrated favorable vascular actions. They increase the bioavailability of vasodilator mediators like nitric oxide, but they have also been shown to inhibit the ET-1 system. These features make gut hormones promising tools for targeting both the metabolic and cardiovascular complications of obesity, a view supported by recent large-scale clinical trials indicating that novel drugs for type 2 diabetes with cardiovascular potential may translate into clinically significant advantages. Therefore, there is real hope that better understanding of the properties of gut-derived substances might provide more effective therapies for the obesity-related cardiometabolic syndrome.

Arterial ageing: from endothelial dysfunction to vascular calcification.

Complex structural and functional changes occur in the arterial system with advancing age. The aged artery is characterized by changes in microRNA expression patterns, autophagy, smooth muscle cell migration and proliferation, and arterial calcification with progressively increased mechanical vessel rigidity and stiffness. With age the vascular smooth muscle cells modify their phenotype from contractile to 'synthetic' determining the development of intimal thickening as early as the second decade of life as an adaptive response to forces acting on the arterial wall. The increased permeability observed in intimal thickening could represent the substrate on which low-level atherosclerotic stimuli can promote the development of advanced atherosclerotic lesions. In elderly patients the atherosclerotic plaques tend to be larger with increased vascular stenosis. In these plaques there is a progressive accumulation of both lipids and collagen and a decrease of inflammation. Similarly the plaques from elderly patients show more calcification as compared with those from younger patients. The coronary artery calcium score is a well-established marker of adverse cardiovascular outcomes. The presence of diffuse calcification in a severely stenotic segment probably induces changes in mechanical properties and shear stress of the arterial wall favouring the rupture of a vulnerable lesion in a less stenotic adjacent segment. Oxidative stress and inflammation appear to be the two primary pathological mechanisms of ageing-related endothelial dysfunction even in the absence of clinical disease. Arterial ageing is no longer considered an inexorable process. Only a better understanding of the link between ageing and vascular dysfunction can lead to significant advances in both preventative and therapeutic treatments with the aim that in the future vascular ageing may be halted or even reversed.

Vascular hyperpolarization in human physiology and cardiovascular risk conditions and disease.

Hyperpolarization causing smooth muscle relaxation contributes to the maintenance of vascular homeostasis, particularly in small-calibre arteries and arterioles. It may also become a compensatory vasodilator mechanism upregulated in states with impaired nitric oxide (NO) availability. Bioassay of vascular hyperpolarization in the human circulation has been hampered by the complexity of mechanisms involved and the limited availability of investigational tools. Firm evidence, however, supports the notion that hyperpolarization participates in the regulation of resting vasodilator tone and vascular reactivity in healthy subjects. In addition, an enhanced endothelium-derived hyperpolarization contributes to both resting and agonist-stimulated vasodilation in a variety of cardiovascular risk conditions and disease. Thus, hyperpolarization mediated by epoxyeicosatrienoic acids (EETs) and H2 O2 has been observed in coronary arterioles of patients with coronary artery disease. Similarly, ouabain-sensitive and EETs-mediated hyperpolarization has been observed to compensate for NO deficiency in patients with essential hypertension. Moreover, in non-hypertensive patients with multiple cardiovascular risk factors and in hypercholesterolaemia, KCa channel-mediated vasodilation appears to be activated. A novel paradigm establishes that perivascular adipose tissue (PVAT) is an additional regulator of vascular tone/function and endothelium is not the only agent in vascular hyperpolarization. Indeed, some PVAT-derived relaxing substances, such as adiponectin and angiotensin 1-7, may exert anticontractile and vasodilator actions by the opening of KCa channels in smooth muscle cells. Conversely, PVAT-derived factors impair coronary vasodilation via differential inhibition of some K+ channels. In view of adipose tissue abnormalities occurring in human obesity, changes in PVAT-dependent hyperpolarization may be relevant for vascular dysfunction also in this condition.

Obesity and kidney disease: Beyond the hyperfiltration.

In industrialized countries, overweight and obesity account for approximately 13.8% and 24.9% of the kidney disease observed in men and women, respectively. Moreover, obesity-associated glomerulopathy is now considered as "an emerging epidemic." Kidney function can be negatively impacted by obesity through several mechanisms, either direct or indirect. While it is well established that obesity represents the leading risk factor for type 2 diabetes and hypertension, awareness that obesity is associated with direct kidney damage independently of hypertension and diabetes is still not widespread. In this paper we will discuss the emerging role of adipose tissue, particularly in the visceral depot, in obesity-induced chronic kidney damage.

Carotid free-floating thrombus in woman with meningioma: a case report and review of the literature.

OBJECTIVE: Several reports have previously described the coexistence of severe carotid artery disorders and brain tumors, in particular meningioma, mainly consisting of arterial occlusion or obstruction due to direct compression by tumor mass, with possible presence of transient neurological symptoms as well as complete cerebral infarction. Free-floating thrombus (FFT) is an uncommon condition, characterized by the presence of thrombotic material partially attached to the arterial wall with evidence of heartbeat associated floating. To our knowledge, our case represents the first report in literature about presence of internal carotid FFT in patient affected by meningioma. CASE REPORT: In this report, sharing singular images and videos of this uncommon condition, we present the first case of a right internal carotid artery FFT in a 59-year-old woman affected by meningioma, successfully treated with antiplatelet medication together with anticoagulation and high dose of statins. CONCLUSIONS: Our case confirms the possible association between carotid artery disorders and meningioma, involving for the first time a FFT. These findings make desirable to explore carotid district in patients with brain tumors, especially meningioma, even if symptoms suggestive of ischemic suffering are not present, in order to make an early diagnosis, so preventing marked ischemic events.

The possible role of glutathione-S-transferase activity in diabetic nephropathy.

The most common cause of end stage renal disease is diabetic nephropathy. An early diagnosis may allow an intervention to slow down disease progression. Recently, it has been hypothesized that glutathione-S-transferase (GST) activity may be a marker of severity of chronic kidney disease. In particular, a lower GST activity is present in healthy subjects compared to patients with nephropathy. In the present review we illustrate the scientific evidence underlying the possible role of GST activity in the development of diabetic nephropathy and we analyze its usefulness as a possible early biomarker of this diabetic complication.

Gut hormones and endothelial dysfunction in patients with obesity and diabetes.

Overweight and obesity are the fifth leading risk for global deaths and its prevalence has doubled since 1980. At least 2.8 million adults, worldwide, die each year as a result of being overweight or obese. The deleterious effects of obesity are tightly related to diabetes, as they are often clinically present in combination to confer increased cardiovascular mortality. Thus, patients with diabetes and obesity are known to develop accelerated atherosclerosis characterized by a dysfunctional endothelium and decreased nitric oxide bioavailability. Recent clinical studies support, indeed, the use of incretin-based antidiabetic therapies for vascular protection. Thus, attention has been focusing on gut hormones and their role, not only in the regulation of appetite but also in vascular health. Intervention directed at modulating these molecules has the potential to decrease mortality of patients with diabetes and obesity. This review will cover part of the ongoing research to understand the role of gut hormones on endothelial function and vascular health.

Obesity, inflammation and endothelial dysfunction.

Cardiovascular disease is the leading cause of morbidity and mortality in obese individuals. Obesity dramatically increases the risk of development of metabolic and cardiovascular disease. This risk appears to originate from disruption in adipose tissue function leading to a chronic inflammatory state and to dysregulation of the endocrine and paracrine actions of adipocyte-derived factors. These, in turn, impair vascular homeostasis and lead to endothelial dysfunction. An altered endothelial cell phenotype and endothelial dysfunction are common among all obesity-related complications. A crucial aspect of endothelial dysfunction is reduced nitric oxide (NO) bioavailability. A systemic pro-inflammatory state in combination with hyperglycemia, insulin resistance, oxidative stress and activation of the renin angiotensin system are systemic disturbances in obese individuals that contribute independently and synergistically to decreasing NO bioavailability. On the other hand, pro-inflammatory cytokines are locally produced by perivascular fat and act through a paracrine mechanism to independently contribute to endothelial dysfunction and smooth muscle cell dysfunction and to the pathogenesis of vascular disease in obese individuals. The promising discovery that obesity-induced vascular dysfunction is, at least in part, reversible, with weight loss strategies and drugs that promote vascular health, has not been sufficiently proved to prevent the cardiovascular complication of obesity on a large scale. In this review we discuss the pathophysiological mechanisms underlying inflammation and vascular damage in obese patients.

Role of radiotherapy boost in women with ductal carcinoma in situ: a single-center experience in a series of 389 patients.

BACKGROUND: The use of adjuvant radiotherapy in ductal carcinoma in situ is accepted by most radiation oncologists worldwide; the role of a boost on the tumor bed is however more controversial. MATERIALS AND METHODS: We reviewed our Institute experience in DCIS treatment, focusing on main prognostic factors and impact of radiation boost on local relapse. A total of 389 patients treated between 1990 and 2007 were retrospectively analyzed. All patients received adjuvant radiotherapy after breast-conserving surgery for a median dose of 50 Gy; 190 patients (48.8%) received and additional radiation boost on the tumor bed. RESULTS: At a mean follow up of 7.7 years, we recorded 26 local recurrence (6.7%). Concerning local relapse-free survival, at Cox regression univariate analyses <1 mm surgical margins (p < 0.0001) and young age (p = 0.01) emerged as significant unfavorable prognostic factors. At multivariate analysis Cox regression model, surgical margins (p < 0.001) and radiation boost (p = 0.014) resulted as the significant independent predictors of recurrence. CONCLUSIONS: Our experience showed the negative prognostic impact of surgical margins <1 mm and the protective role of radiation boost on LR rate. Anyway, results from ongoing prospective Phase III studies are strongly necessary to better identify high-risk DCIS patients.

Drug treatments to restore vascular function and diabesity.

Over the last decades, an escalating rate of type 2 diabetes has paralleled an epidemic rise in the prevalence of obesity. Both diabetes and obesity confer an increased risk of cardiovascular comorbidities, including hypertension, coronary artery disease and stroke. Vascular dysfunction, represented by impaired endothelial release of vasodilator substances or defective smooth muscle vasodilator reactivity, is the early stage of the process leading to atherosclerosis and a common finding in patients with diabesity. It is understandable, therefore, that effective treatments for diabesity should restore vascular function to prevent the development of cardiovascular disease. Recent evidence from clinical studies supports the efficacy of incretin-based antidiabetic therapies for vascular protection. Thus, glucose control with either DDP-4 inhibitor or GLP-1 receptor therapies seems associated with favorable effects on vascular function in diabetes and the metabolic syndrome. Another mechanism to counter excess plasma glucose and reduce body weight in these patients may rely on drug therapies targeting gut hormones, as suggested by the efficacy of bariatric surgery to produce both sustained weight loss and high diabetes remission rates. Also, as knowledge of the multifaceted vascular actions of adipokines and their dysregulation in patients with diabesity increases, these substances become attractive targets for treatments aimed at cardiovascular prevention. The increasing coexistence of diabetes and obesity presents complex treatment challenges owing to the elevated risk of developing cardiovascular complications. Hence, therapeutic strategies integrating glycemic control, weight loss and vascular protection are of the greatest importance to successfully counteract the health and economic burden posed by diabesity.

The recovery of platelet cyclooxygenase activity explains interindividual variability in responsiveness to low-dose aspirin in patients with and without diabetes.

BACKGROUND: Interindividual variability in response to aspirin has been popularized as 'resistance'. We hypothesized that faster recovery of platelet cyclooxygenase-1 activity may explain incomplete thromboxane (TX) inhibition during the 24-h dosing interval. OBJECTIVE: To characterize the kinetics and determinants of platelet cyclooxygenase-1 recovery in aspirin-treated diabetic and non-diabetic patients. PATIENTS/METHODS: One hundred type 2 diabetic and 73 non-diabetic patients on chronic aspirin 100 mg daily were studied. Serum TXB(2) was measured every 3 h, between 12 and 24 h after a witnessed aspirin intake, to characterize the kinetics of platelet cyclooxygenase-1 recovery. Patients with the fastest TXB(2) recovery were randomized to aspirin 100 mg once daily, 200 mg once daily or 100 mg twice daily, for 28 days and TXB(2) recovery was reassessed. RESULTS AND CONCLUSIONS: Platelet TXB(2) production was profoundly suppressed at 12 h in both groups. Serum TXB(2) recovered linearly, with a large interindividual variability in slope. Diabetic patients in the third tertile of recovery slopes (≥ 0.10 ng mL(-1) h(-1) ) showed significantly higher mean platelet volume and body mass index, and younger age. Higher body weight was the only independent predictor of a faster recovery in non-diabetics. Aspirin 100 mg twice daily completely reversed the abnormal TXB(2) recovery in both groups. Interindividual variability in the recovery of platelet cyclooxygenase activity during the dosing interval may limit the duration of the antiplatelet effect of low-dose aspirin in patients with and without diabetes. Inadequate thromboxane inhibition can be easily measured and corrected by a twice daily regimen.

Insulinemia and the risk of breast cancer and its relapse.

A fairly large body of evidence has shown that insulin is a tumour-promoting agent, especially for breast cancer. High circulating and microenvironmental levels of insulin may directly increase the risk of breast cancer via the activation of cognate receptors expressed on normal and cancer cells and indirectly be associated with other known metabolic risk factors of cancer that usually are present in conjunction with the hyperinsulinic state. The focus of this review is to analyse and discuss available data in the literature on the possible causative/prognostic role of insulin resistance/hyperinsulinemia in breast cancer development and progression.

Chronic kidney disease, obesity, and hypertension: the role of leptin and adiponectin.

Chronic kidney disease is a major public health problem and characterized by a progressive loss in renal function over a period of months or years as defined by structural or functional abnormalities of the kidney. Several elements contribute to determine a progression of the kidney injury, inducing a worsening of renal damage and accelerating the decline of renal function: obesity and hypertension are two known factors of kidney progression. Remarkable improvements have been recently achieved in the study of the endocrine features of the adipose tissue and have been able to produce hormone-like peptides named adipokines or adipocytokines. Among these adipocytokines, which represent a link between obesity, hypertension, and chronic nephropathy, leptins and adiponectin appear to play an important role. Leptin not only is a prohypertension element (renal progression factor) through the activation sympathetic nervous, but also is able to induce prosclerotic effects directly on the kidney. In contrast, a decline of adiponectin levels has been shown to be related to a picture of hypertension: an endothelial dysfunction has been described as the main pathogenic mechanism responsible for this phenomenon.

Pegylated liposomal doxorubicin (Caelyx®) and oral vinorelbine in first-line metastatic breast cancer patients previously treated with anthracyclines.

Doxorubicin is highly effective and widely used in breast cancer; however, its use is limited by cardiotoxicity related to its cumulative dose. In previous studies, pegylated liposomal doxorubicin (PLD) has shown an acceptable toxicity profile with minimal cardiotoxicity. Between June 2006 and October 2009, 27 metastatic breast cancer patients were treated with first-line PLD and vinorelbine at the University of Florence, Radiotherapy Unit. PLD (30 mg/m²) was administered on day 1, and oral vinorelbine (60 mg/m²) was administered on days 1 and 8 of a 4-week cycle. All patients were previously treated with anthracycline-based adjuvant chemotherapy. Median age was 52 years (range 38-69) and median time to metastasis was 78.5 months. There were no treatment interruptions or discontinuation for cardiac toxicity and no treatment-related deaths. Grade 3 hematological toxicity was observed in 18.6% of patients, and 3.7% had grade 3 non-hematological adverse events. With a median follow-up of 13.2 months (range 3-33), median response duration was 6.1 months, and median PFS was 5.3 months. The overall clinical benefit rate was 55.5%. Our experience adds to evidence supporting the activity and cardiac safety of PLD and vinorelbine in metastatic breast cancer patients previously treated with anthracycline-based adjuvant chemotherapy.

Use of doxorubicin plus cyclophosphamide followed by docetaxel as adjuvant chemotherapy for breast cancer.

We evaluated the feasibility and incidence of hematological toxicity in a series of 39 breast cancer patients treated at our institute with doxorubicin plus cyclophosphamide (AC) followed by docetaxel, using prophylactic G-CSF (pegfilgrastim). We prescribed G-CSF as secondary prophylaxis during the AC regimen and as primary prophylaxis during treatment with docetaxel. For the AC treatment, we recorded 6 cases of grade III (15.3%) and one case of grade IV (2.5%) neutropenia; we found one case of Grade IV anemia. For the docetaxel regimen, we registered one case of Grade IV (2.5%) neutropenia and three cases of Grade III leukopoenia without neutropenia. No patients experienced cardiac symptoms or baseline LVEF rate decrease. All patients concluded the programmed chemotherapy. Our experience shows the safety of docetaxel in combination with anthracyclines and the efficacy of prophylaxis with G-CSF in breast cancer adjuvant chemotherapy.

Obesity, blood vessels and metabolic syndrome.

Obesity is rising worldwide at an alarming rate and so is the incidence of obesity-related disorders, such as the metabolic syndrome, type 2 diabetes and cardiovascular diseases. The obesity-dependent vascular damage appears to be derived from a variety of changes in the adipose tissue, leading to a chronic inflammatory state and dysregulation of adipocyte-derived factors. This, in turn, impairs vascular homeostasis by determining an unbalance between the protective effect of the nitric oxide pathway and the unfavourable action of the endothelin-1 system. In addition, hyperinsulinemia and insulin resistance contribute to vascular dysfunction because the opposing endothelium-dependent vasodilating and vasoconstrictor effects of insulin are shifted towards a predominant vasoconstriction in patients with obesity. Importantly, emerging evidence suggests that the vascular dysfunction of obesity is not only limited to the endothelium but also involves the other layers of the vessel wall. In particular, obesity-related changes in vascular smooth muscle seem to disrupt the physiological facilitatory action of insulin on the responsiveness to vasodilator stimuli, whereas the adventitia and the perivascular fat appear to be a source of proinflammatory and vasoactive factors that may contribute to endothelial and smooth muscle cell dysfunction and to the pathogenesis of vascular disease.

Postmastectomy radiotherapy in breast cancer adjuvant treatment.

Radiotherapy (RT) plays an important role in the management of locally advanced breast cancer (BC). Postmastectomy RT has been shown to significantly reduce the risk of loco-regional failure and to improve disease free survival in high-risk women with BC. Many trials have shown a significant benefit in local control, disease-free and overall survival with the addition of RT for patients with stage II and III breast cancer. New perspectives are evaluating multiple biological variables that nowadays should be considered in clinical oncology for the prescription of postmastectomy radiation therapy. Tailored randomized trials are now ongoing to clarify the "grey zone" represented by the intermediate-risk group of patients (1-3 lymph nodes involved). We reviewed the major studies offered by literature with emphasis on the principal debated issues.

Adjuvant trastuzumab in breast cancer: experience from the University of Florence.

The objective of this study was to evaluate the efficacy and tolerability profile of sequential trastuzumab in the adjuvant treatment of non-metastatic breast cancer. We analyzed 94 patients with non-metastatic breast cancer who underwent postoperative treatment between November 2003 and December 2008 at the University of florence. All patients received one year of sequential trastuzumab after adjuvant chemotherapy. Cardiac monitoring in our study consisted of assessment of left ventricular ejection fraction (lVef) by echocardiography at baseline, after the completion of chemotherapy, then every 3 months during trastuzumab treatment and every 6 months thereafter. 91.6% of patients were alive without evidence of distant or local relapse, while 8.4% developed disease recurrence. The cumulative incidence of cardiotoxicity was 14.5%. In our experience trastuzumab given postoperatively with adjuvant chemotherapy was well tolerated and produced optimal clinical results in terms of disease-free survival.

Oral ibandronate in metastatic bone breast cancer: the Florence University experience and a review of the literature.

Ibandronate is an amino-bisphosphonate approved in metastatic breast cancer to reduce skeletal complications and to alleviate bone pain. we report our experience about the safety of oral ibandronate and review the literature.We treated 44 patients and administered 524 cycles of oral ibandronate (a single cycle was defined as a 50 mg capsule once daily for 28 days) with a median of 12 cycles (range 6-24). At a median follow-up of 18.5 months (range 6-28) the mean pain score decreased from 1.59 (SD+/-0.97) at baseline to 0.41 (SD+/-0.72) after 48 weeks of treatment. The mean analgesic score was 1.89 (SD+/-1.37) at baseline and 1.46 (SD+/-1.62) after 48 weeks of treatment. Ibandronate was generally well-tolerated; we had no Grade 3-4 adverse events. No patients had deterioration of renal function. No patients developed bisphosphonate-associated osteonecrosis of the jaw. Our experience confirmed that ibandronate may be a useful and safe co-analgesic to conventional treatments for bone pain in selected metastatic breast cancer patients.