Phosphorylation of rat brain calpastatins by protein kinase C

AbstractCalpastatin, the natural inhibitor of calpain, is present in rat brain in multiple forms, having different molecular masses, due to the presence of one (low Mr form) or four (high Mr form) repetitive inhibitory domains. Recombinant and native calpastatin forms are substrates of protein kinase C, which phosphorylates a single serine residue at their N-terminus. Furthermore, both low and high Mr calpastatins are phosphorylated by protein kinase C at the same site. These calpastatin forms are phosphorylated also by protein kinase A, although with a lower efficiency. The incorporation of a phosphate group determines an increase in the concentration of Ca2+ required to induce the formation of the calpain-calpastatin complex. This effect results in a large decrease of the inhibitory efficiency of calpastatins. We suggest that phosphorylation of calpastatin represents a mechanism capable to balance the actual amount of active calpastatin to the level of calpain to be activated

Trattamento dell’iperuricemia nel paziente nefropatico: è giunto il momento di agire?

Numerosi studi epidemiologici condotti nella popolazione generale indicano che l\u2019iperuricemia si associa ad un incremento del rischio di sviluppare insufficienza renale. Inoltre, tra i soggetti che sono gi\ue0 affetti da una malattia renale cronica (MRC), l\u2019iperuricemia si associa sia ad una pi\uf9 rapida progressione di malattia sia ad un significativo incremento della mortalit\ue0 e degli eventi cardiovascolari. Tuttavia, ad oggi il ruolo causale dell\u2019iperuricemia nel determinare l\u2019insorgenza e la progressione del danno renale e cardiovascolare non \ue8 ancora completamente accertato, per cui le indicazioni al trattamento farmacologico dell\u2019iperuricemia asintomatica nei pazienti con MRC sono ancora affidate all\u2019orientamento personale del singolo medico. Al fine di stabilire se sia possibile esprimere un orientamento clinico basato sull\u2019evidenza abbiamo eseguito un\u2019analisi comparativa degli studi prospettici che hanno valutato l\u2019impatto della terapia ipouricemizzante con inibitori della xantino ossidasi (IXAO) rispetto all\u2019insorgenza e alla progressione del danno renale. Inoltre, dal momento che in passato nei soggetti con funzionalit\ue0 renale ridotta il trattamento con IXAO \ue8 stato associato ad un elevato rischio di tossicit\ue0, abbiamo analizzato la tossicit\ue0 di questi farmaci per vari gradi compromissione della funzione renale riassumendo indicazioni, controindicazioni e dosi consigliate nei pazienti affetti da MRC. In fine, a conclusione della nostra analisi abbiamo elaborato un algoritmo finalizzato ad orientare le decisioni cliniche in merito al trattamento dell\u2019iperuricemia nei soggetti affetti da MRC.Numerous epidemiological studies conducted in the general population indicate that hyperuricemia is associated with an increased risk of developing renal failure. Moreover, among those subjects who are already suffering from chronic kidney disease (CKD), hyperuricemia is associated with a more rapid progression of disease besides with an increased risk of mortality and cardiovascular events. However, to date, the causal role of hyperuricaemia in determining the onset and progression of cardiovascular and renal damage is not yet fully established. Therefore the indications for pharmacological treatment of hyperuricemia (and particulary of asymptomatic hyperuricemia) in patients with CKD are still assigned to the personal orientation of the physician. In order to produce an evidence-based clinical appraisal on this topic, we performed a comparative analysis that included all the prospective studies that have evaluated the impact of treatment with xanthine oxidase inhibithors (XOI) with respect to the onset and progression of CKD. Moreover, since in the past the treatment with XOI was associated with a high risk of toxicity in patients with impaired renal function, we analyzed the toxicity of these drugs for various degrees of renal function impairment summarizing indications, contraindications and recommended doses in patients affected by CKD. In the end, as conclusion of our analysis, we propose an algorithm aimed at guiding the clinical decisions about the treatment of hyperuricemia in patients with CKD

Cardiovascular and renal effects of hyperuricaemia and gout.

A number of epidemiological studies have reported an association between serum uric acid levels and a wide variety of high-risk conditions including hypertension, insulin resistance, and kidney and cerebro-cardiovascular disease. All things considered, serum uric acid may induce cardiovascular and kidney events both directly and indirectly by promoting other well-known mechanisms of damage. While asymptomatic hyperuricemia is currently not considered to be an indication for urate lowering therapy, there is growing evidence indicating a linear relationship between pharmacological reduction in serum uric acid and incidence of cardiovascular and renal events

Natural history and risk factors for diabetic kidney disease in patients with T2D: lessons from the AMD-annals

The Associazione Medici Diabetologi (AMD) annals initiative is an ongoing observational survey promoted by AMD. It is based on a public network of about 700 Italian diabetes clinics, run by specialists who provide diagnostic confirmation and prevention and treatment of diabetes and its complications. Over the last few years, analysis of the AMD annals dataset has contributed several important insights on the clinical features of type-2 diabetes kidney disease and their prognostic and therapeutic implications. First, non-albuminuric renal impairment is the predominant clinical phenotype. Even though associated to a lower risk of progression compared to overt albuminuria, it contributes significantly to the burden of end-stage renal disease morbidity. Second, optimal blood pressure control provides significant but incomplete renal protection. It reduces albuminuria but there may be a J curve phenomenon with eGFR at very low blood pressure values. Third, hyperuricemia and diabetic hyperlipidemia, namely elevated triglycerides and low HDL cholesterol, are strong independent predictors of chronic kidney disease (CKD) onset in diabetes, although the pathogenetic mechanisms underlying these associations remain uncertain. Fourth, the long-term intra-individual variability in HbA1c, lipid parameters, uric acid and blood pressure plays a greater role in the appearance and progression of CKD than the absolute value of each single variable. These data help clarify the natural history of CKD in patients with type 2 diabetes and provide important clues for designing future interventional studies

Hybrid injectable platforms for the in situ delivery of therapeutic ions from mesoporous glasses

Copper-containing bioactive glasses (Cu-MBGs) are attracting increasing interest as multifunctional agents for hard and soft tissue healing due to the ability of released copper ions to stimulate osteogenesis as well as angiogenesis and to impart anti-bacterial properties. The conjugation of these nanomaterials with a vehicle phase based on thermosensitive hydrogels represents an effective strategy to design non-invasive injectable devices for the in situ delivery of therapeutic ions from MBGs. In this contribution, Cu-containing MBGs were prepared by an aerosol-assisted spray-drying method (MBG_Cu 2%_SD) in the form of microspheres (surface area of ca 220m2 g−1) and through a sol-gel synthesis (MBG_Cu 2% _SG) in the form of spheroidal nanoparticles (surface area above 700m2 g−1). Both Cu-containing samples were able to release copper ions, although with different rates and percentage release. MBG_Cu 2%_SG released the total incorporated amount of Cu ions with a faster kinetics compared to MBG_Cu 2%_SD, that released approximately the 60% of copper. Cu-MBGs were incorporated with a final concentration of 20 mg/mL into a thermosensitive sol-gel system consisting of a novel amphiphilic poly(ether urethane) based on a commercialy available Poloxamer 407 (P407), with improved gelation ability, mechanical strength and stability in aqueous solution with respect to native P407. Cu-MBG-loaded hydrogels were characterised in terms of sol-to-gel transition temperature and time, injectability and stability in aqueous environment at 37 °C. The hybrid formulations showed fast gelation in physiological conditions (1 mL underwent complete sol-to-gel transition within 3–5 min at 37 °C) and injectability in a wide range of temperatures (5–37 °C) through different needles (inner diameter in the range 0.6–1.6 mm)

Sr-containing mesoporous bioactive glasses bio-functionalized with recombinant ICOS-Fc: An in vitro study

Osteoporotic bone fractures represent a critical clinical issue and require personalized and specific treatments in order to stimulate compromised bone tissue regeneration. In this clinical context, the development of smart nano-biomaterials able to synergistically combine chemical and biological cues to exert specific therapeutic effects (i.e., pro-osteogenic, anti-clastogenic) can allow the design of effective medical solutions. With this aim, in this work, strontium-containing mesoporous bioactive glasses (MBGs) were bio-functionalized with ICOS-Fc, a molecule able to reversibly inhibit osteoclast activity by binding the respective ligand (ICOS-L) and to induce a decrease of bone resorption activity. N2 adsorption analysis and FT-IR spectroscopy were used to assess the successful grafting of ICOS-Fc on the surface of Sr-containing MBGs, which were also proved to retain the peculiar ability to release osteogenic strontium ions and an excellent bioactivity after functionalization. An ELISA-like assay allowed to confirm that grafted ICOS-Fc molecules were able to bind ICOS-L (the ICOS binding ligand) and to investigate the stability of the amide binding to hydrolysis in aqueous environment up to 21 days. In analogy to the free form of the molecule, the inhibitory effect of grafted ICOS-Fc on cell migratory activity was demonstrated by using ICOSL positive cell lines and the ability to inhibit osteoclast differentiation and function was confirmed by monitoring the differentiation of monocyte-derived osteoclasts (MDOCs), which revealed a strong inhibitory effect, also proven by the downregulation of osteoclast differentiation genes. The obtained results showed that the combination of ICOS-Fc with the intrinsic properties of Sr-containing MBGs represents a very promising approach to design personalized solutions for patients affected by compromised bone remodeling (i.e., osteoporosis fractures)

Blood pressure control in Italy: analysis of clinical data from 2005-2011 surveys on hypertension

Introduction: Blood pressure (BP) control is poorly achieved in hypertensive patients, worldwide. Aim: We evaluated clinic BP levels and the rate of BP control in hypertensive patients included in observational studies and clinical surveys published between 2005 and 2011 in Italy. Methods: We reviewed the medical literature to identify observational studies and clinical surveys on hypertension between January 2005 and June 2011, which clearly reported information on clinic BP levels, rates of BP control, proportions of treated and untreated patients, who were followed in different clinical settings (mostly in general practice, and also in outpatient clinics and hypertension centres). Results: The overall sample included 158 876 hypertensive patients (94 907 women, mean age 56.6 +/- 9.6 years, BMI 27.2 +/- 4.2 kg/m(2), known duration of hypertension 90.2 +/- 12.4 months). In the selected studies, average SBP and DBP levels were 145.7 +/- 15.9 and 87.5 +/- 9.7 mmHg, respectively; BP levels were higher in patients followed in hypertension centres (n = 10 724, 6.7%; 146.5 +/- 17.3/88.5 +/- 10.3 mmHg) than in those followed by general practitioners (n = 148 152, 93.3%; 143.5 +/- 13.9/84.8 +/- 8.9 mmHg; P < 0.01). More than half of the patients were treated (n = 91 318, 57.5%); among treated hypertensive patients, only 31 727 (37.0%) had controlled BP levels. Conclusion: The present analysis confirmed inadequate control of BP in Italy, independently of the clinical setting. Although some improvement was noted compared with a similar analysis performed between 1995 and 2005, these findings highlight the need for a more effective clinical management of hypertension

SGLT-2 inhibitors for treatment of heart failure in patients with and without type 2 diabetes: A practical approach for routine clinical practice

Sodium-glucose cotransporter-2 inhibitors (SGLT-2i), initially studied and approved for the treatment of diabetes, are now becoming a promising class of agents to treat heart failure (HF) and chronic kidney disease (CKD), even in patients without diabetes. While the potential benefits in several diseases (usually treated by different medical specialties) is amplifying the interest in these drugs, their use in frail patients with multiple pathologies and on polypharmacy can be complex, requiring a composite multidisciplinary approach. Following a brief overview of the evidence supporting the benefits of SGLT-2i in patients with HF or CKD, we herein provide guidance for prescribing SGLT-2i in daily practice using a multidisciplinary approach. A shared treatment algorithm is presented for initiating an SGLT-2i in patients already being treated for diabetes and HF. Tools to prevent hypoglycemia, blood pressure drop, genital infections, euglycemic diabetic ketoacidosis and eGFR dip are also provided. It is hoped that this practical, multidisciplinary guidance for initiating SGLT-2i in patients with HF and/or CKD, whatever therapy they are currently on, can help to offer SGLT-2i to the largest population of patients possible to provide the most therapeutic benefit

Ancient Evolution of Mammarenaviruses: Adaptation via Changes in the L Protein and No Evidence for Host-Virus Codivergence

The Mammarenavirus genus includes several pathogenic species of rodent-borne viruses. Old World (OW) mammarenaviruses infect rodents in the Murinae subfamily and are mainly transmitted in Africa and Asia; New World (NW) mammarenaviruses are found in rodents of the Cricetidae subfamily in the Americas. We applied a selection-informed method to estimate that OW and NW mammarenaviruses diverged less than 3c45,000\u2009years ago (ya). By incorporating phylogeographic inference, we show that NW mammarenaviruses emerged in the Latin America-Caribbean region 3c41,400-3,300 ya, whereas OW mammarenaviruses originated 3c23,100-1,880 ya, most likely in Southern Africa. Cophylogenetic analysis indicated that cospeciation did not contribute significantly to mammarenavirus-host associations. Finally, we show that extremely strong selective pressure on the viral polymerase accompanied the speciation of NW viruses. These data suggest that the evolutionary history of mammarenaviruses was not driven by codivergence with their hosts. The viral polymerase should be regarded as a major determinant of mammarenavirus adaptation