The treatment of hyperuricemia.

AbstractHyperuricemia has long been established as the major etiologic factor in gout. Alongside with an inflammatory state triggered by urate crystal deposition in the joints, hyperuricemia displayed additional pathophysiological consequences leading to tissue inflammation mainly in the vascular wall. Thus, therapeutic strategies used to treat hyperuricemia in the past decades have often been focused on limiting acute episodes. Recently, evidence has been accumulated suggesting that chronic urate deposition requires a correct treatment not limited to acute episodes based on the modulation of the activity of key enzymes involved in metabolism and excretion of urate including xanthine oxidoreductase (XO) and URAT1. The present review article will try to summarize the most recent evidences on the efficacy of XO inhibitors and uricosuric compounds in lowering uric acid levels in both the bloodstream and peripheral tissues. In particular, we will focus on the effect of novel XO inhibitors in counteracting uric acid overproduction. On the other hand, the effect of lowering uric acid levels via XO inhibition will be correlated with attenuation oxidative stress which leads to endothelial dysfunction thereby contributing to the pathophysiology of diabetes, hypertension, arteriosclerosis, and chronic heart failure. Hence, scavenging and prevention of the XO generated oxygen radical accumulation emerge as an intriguing novel treatment option to counteract uric acid-induced tissue damages

The protective effect of M40401, a superoxide dismutase mimetic, on post-ischemic brain damage in Mongolian gerbils

BACKGROUND: Overproduction of free radical species has been shown to occur in brain tissues after ischemia-reperfusion injury. However, most of free radical scavengers known to antagonize oxidative damage (e.g. superoxide dismutase, catalase), are unable to protect against ischemia-reperfusion brain injury when given in vivo, an effect mainly due to their difficulty to gain access to brain tissues. Here we studied the effect of a low molecular weight superoxide dismutase mimetic (M40401) in brain damage subsequent to ischemia-reperfusion injury in Mongolian gerbils. RESULTS: In animals undergoing ischemia-reperfusion injury, neuropathological and ultrastructural changes were monitored for 1–7 days either in the presence or in the absence of M40401 after bilateral common carotid artery occlusion (BCCO). Administration of M40401 (1–40 mg/kg, given i.p. 1 h after BCCO) protected against post-ischemic, ultrastructural and neuropathological changes occurring within the hippocampal CA1 area. The protective effect of M40401 was associated with a significant reduction of the levels of malondialdehyde (MDA; a marker of lipid peroxidation) in ischemic brain tissues after ischemia-reperfusion. CONCLUSION: Taken together, these results demonstrate that M40401 provides protective effects when given early after the induction of ischemia-reperfusion of brain tissues and suggest the possible use of such compounds in the treatment of neurological dysfunction subsequent to cerebral flow disturbances

Enjoy your journey: the bergamot polyphenols from the tree to the cell metabolism

No abstract availabl

Progression of Lactobacillus plantarum prosthetic valve endocarditis followed by transesophageal echocardiogram

Endocarditis due to Lactobacillus species is extremely rare. We report an uncommon case of Lactobacillus plantarum bioprosthetic aortic valve endocarditis, presenting with severe aortic steno-regurgitation, which responded to conventional medical and surgical treatment. This case provides a better understanding of the disease process of L. plantarum and highlights the role of transesophageal echocardiography in following the entire course of endocarditis

The Effect of Bergamot-Derived Polyphenolic Fraction on LDL Small Dense Particles and Non Alcoholic Fatty Liver Disease in Patients with Metabolic Syndrome

The occurrence of Metabolic Syndrome (MS) represents an independent risk factor for developing cardiovascular disease states in patients suffering from type 2 diabetes mellitus. Moreover, both the size of LDL particles and liver dysfunction identified as non alcoholic fatty liver disease (NAFLD) represent important biomarkers for the development of cardiometabolic risk in patients with MS. Here we studied the effect of bergamot polyphenolic fraction (BPF) in patients with MS and NAFLD. 107 patients were enrolled at the San Raffaele IRCCS (Rome). All of them showed ultrasonografic evidences of NAFLD and at least three out of five previous identified criteria for the diagnosis of MS. Patients were divided into two groups: one receiving placebo and the second receiving BPF 650 mg twice a day for 120 consecutive days. In the group receiving BPF 650 mg twice a day, a significant reduction of fasting plasma glucose, serum LDL cholesterol and triglycerides alongside with an increase of HDL cholesterol was found. This effect was accompanied by significant reduction of both ultrasonographic and metabolic biomarkers of NAFLD. Moreover, a significant reduction of small dense LDL particles, as detected via proton NMR Spectroscopy, was found after BPF treatment. In conclusion, our data confirm the beneficial effect of bergamot-extract in patients with MS an effect highlighted by significant reduction of small dense LDL particles and by improvement of NAFLD biomarkers. This suggests a potential preventive role of bergamot derivatives in reducing cardiometabolic risk

Imbalance of thalamic metabolites in an experimental model of hypertension: role of bergamot polyphenols

Cerebral metabolites are associated with different physiological and pathological processes in brain tissue. Among them, the concentrations of N-acetylaspartate (NAA) and choline-containing compounds (Cho) in the thalamic region are recognized and analyzed as important predictive markers of brain impairment. The relationship among hypertension, modulation of brain metabolite levels and cerebral diseases is of recent investigation, leaving many unanswered questions regarding the origin and consequences of the metabolic damage caused in grey and white matter during hypertension. Here we provide evidence for the influence of hypertension on NAA and Cho ratios in hypertensive rat thalamus and how the use of natural occurring compounds ameliorates the balance of thalamic metabolites

PARP inhibitors affect growth, survival and radiation susceptibility of human alveolar and embryonal rhabdomyosarcoma cell lines

PARP inhibitors (PARPi) are used in a wide range of human solid tumours but a limited evidence is reported in rhabdomyosarcoma (RMS), the most frequent childhood soft-tissue sarcoma. The cellular and molecular effects of Olaparib, a specific PARP1/2 inhibitor, and AZD2461, a newly synthesized PARP1/2/3 inhibitor, were assessed in alveolar and embryonal RMS cells both as single-agent and in combination with ionizing radiation (IR)

Bacterial Lipopolysaccharide Plus Interferon-γ Elicit a Very Fast Inhibition of a Ca2+-dependent Nitric-oxide Synthase Activity in Human Astrocytoma Cells

Abstract Previous results indicate that induction of inducible nitric-oxide synthase (iNOS) expression may be kept suppressed by the endogenous NO level as produced by a constitutive NOS (cNOS) enzyme. In cell types possessing both cNOS and iNOS, this may represent an evident paradox. Here, we report that lipopolysaccharide and interferon-γ, which are able to strongly induce iNOS in astrocytoma cells, can rapidly inhibit the NO production generated by the constitutive NOS isoform, thus obtaining the best conditions for iNOS induction and resolving the apparent paradox. In fact, a 30-min treatment of T67 cells with the combination of lipopolysaccharide plus interferon-γ (MIX) strongly inhibits the cNOS activity, as determined by measuring [3H]citrulline production. In addition, the effect of MIX is also observed by measuring nitrite, the stable breakdown product of NO: a 30-min pretreatment of T67 cells with MIX is able to reduce significantly the N-methyl-D-aspartate-induced nitrite production. Finally, using reverse transcriptase-polymerase chain reaction, we have observed that a 30-min treatment of T67 cells with MIX does not affect expression of mRNA coding for the neuronal NOS-I isoform. These results suggest the novel concept of a possible role of a cNOS isoform in astrocytes as a control function on iNOS induction

Improvement of skeletal muscle performance in ageing by the metabolic modulator Trimetazidine

BACKGROUND: The loss of muscle mass (sarcopenia) and the associated reduced muscle strength are key limiting factors for elderly people's quality of life. Improving muscle performance does not necessarily correlate with increasing muscle mass. In fact, particularly in the elderly, the main explanation for muscle weakness is a reduction of muscle quality rather than a loss of muscle mass, and the main goal to be achieved is to increase muscle strength. The effectiveness of Trimetazidine (TMZ) in preventing muscle functional impairment during ageing was assessed in our laboratory. METHODS: Aged mice received TMZ or vehicle for 12 consecutive days. Muscle function was evaluated at the end of the treatment by a grip test as well as by an inverted screen test at 0, 5, 7 and 12 days of TMZ treatment. After sacrifice, muscles were stored for myofiber cross‐sectional area assessment and myosin heavy chain expression evaluation by western blotting. RESULTS: Chronic TMZ treatment does not affect the mass of both gastrocnemius and tibialis anterior muscles, while it significantly increases muscle strength. Indeed, both latency to fall and grip force are markedly enhanced in TMZ‐treated versus untreated mice. In addition, TMZ administration results in higher expression of slow myosin heavy chain isoform and increased number of small‐sized myofibers. CONCLUSIONS: We report here some data showing that the modulation of skeletal muscle metabolism by TMZ increases muscle strength in aged mice. Reprogramming metabolism might therefore be a strategy worth to be further investigated in view of improving muscle performance in the elderly