1,643 research outputs found
A long-term "memory" of HIF induction in response to chronic mild decreased oxygen after oxygen normalization
Background
Endothelial dysfunction (ED) is functionally characterized by decreased vasorelaxation, increased thrombosis, increased inflammation, and altered angiogenic potential, has been intimately associated with the progression and severity of cardiovascular disease. Patients with compromised cardiac function oftentimes have a state of chronic mild decreased oxygen at the level of the vasculature and organs, which has been shown to exacerbate ED. Hypoxia inducible factor (HIF) is a transcription factor complex shown to be the master regulator of the cellular response to decreased oxygen levels and many HIF target genes have been shown to be associated with ED.
Methods
Human endothelial and aortic smooth muscle cells were exposed either to A) normoxia (21% O2) for three weeks, or to B) mild decreased oxygen (15% O2) for three weeks to mimic blood oxygen levels in patients with heart failure, or to C) mild decreased oxygen for two weeks followed by one week of normoxia ("memory" treatment). Levels of HIF signaling genes (HIF-1α, HIF-2α, VEGF, BNIP3, GLUT-1, PAI-1 and iNOS) were measured both at the protein and mRNA levels.
Results
It was found that chronic exposure to mild decreased oxygen resulted in significantly increased HIF signaling. There was also a "memory" of HIF-1α and HIF target gene induction when oxygen levels were normalized for one week, and this "memory" could be interrupted by adding a small molecule HIF inhibitor to the last week of normalized oxygen. Finally, levels of ubiquitylated HIF-1α were reduced in response to chronic mild decreased oxygen and were not full restored after oxygen normalization.
Conclusion
These data suggest that HIF signaling may be contributing to the pathogenesis of endothelial dysfunction and that normalization of oxygen levels may not be enough to reduce vascular stress
Big data and diabetes: the applications of big data for diabetes care now and in the future
Aims: Review the current applications of Big Data in diabetes care and consider the future potential.
Methods: Scoping study of the academic literature on Big Data and diabetes care.
Results: Healthcare data are being produced at ever-increasing rates, and this information has the potential to transform the provision of diabetes care. Big Data is beginning to have an impact on diabetes care through data research. The use of Big Data for routine clinical care is still a future application.
Conclusions: Vast amounts of healthcare data are already being produced, and the key is harnessing these to produce actionable insights. Considerable development work is required to achieve these goals
The glucose triad and its role in comprehensive glycaemic control: current status, future management
The prevalence of type 2 diabetes across the world has been described as a global pandemic. Despite significant efforts to limit both the increase in the number of cases and the long-term impact on morbidity and mortality, the total number of people with diabetes is projected to continue to rise and most patients still fail to achieve adequate glycaemic control. Optimal management of type 2 diabetes requires an understanding of the relationships between glycosylated haemoglobin (HbA1c), fasting plasma glucose and postprandial glucose (the glucose triad), and how these change during development and progression of the disease. Early and sustained control of glycaemia remains important in the management of type 2 diabetes. The contribution of postprandial glucose levels to overall glycaemic control and the role of postprandial glucose targets in disease management are currently debated. However, many patients do not reach HbA1C targets set according to published guidelines. As recent data suggest, if driving HbA1C down to lower target levels is not the answer, what other factors involved in glucose homeostasis can or should be targeted? Has the time come to change the treatment paradigm to include awareness of the components of the glucose triad, the existence of glucose variability and their potential influence on the choice of pharmacological treatment? It is becomingly increasingly clear that physicians are likely to have to consider plasma glucose levels both after the overnight fast and after meals as well as the variability of glucose levels, in order to achieve optimal glycaemic control for each patient. When antidiabetic therapy is initiated, physicians may need to consider selection of agents that target both fasting and postprandial hyperglycaemia
Hypothesis: the "metabolic memory" - the new challenge of diabetes
W dużych randomizowanych badaniach wykazano,
że intensywne wyrównywanie glikemii od samego
początku po rozpoznaniu cukrzycy zmniejsza ryzyko
rozwoju powikłań cukrzycy zarówno mikro-, jak
i makroangiopatii. Jednak wyniki badań epidemiologicznych
i dane prospektywne wskazują, że wpływ
kontroli metabolicznej we wczesnej fazie na efekty
kliniczne jest długofalowy. To zjawisko określono
ostatnio jako "pamięć metaboliczną". Do potencjalnych
mechanizmów propagacji tej "pamięci" należą
nieenzymatyczna glikacja białek i lipidów komórkowych
oraz nadmiar reaktywnego tlenu i azotu w komórce,
w szczególności powstający na poziomie
glikowanych białek mitochondriów, które prawdopodobnie
współdziałają w celu utrzymania procesów
sygnałowania w komórce. Sformułowanie teorii
"pamięci metabolicznej" wskazuje na konieczność
wczesnego intensywnego leczenia cukrzycy, którego
celem jest normalizacja glikemii, oraz włączania
do terapii substancji redukujących reaktywne związki
w komórkach oraz zmniejszających glikację, aby
zminimalizować odległe powikłania tej choroby.Large randomized studies have established that early
intensive glycaemic control reduces the risk of diabetic
complications, both micro- and macrovascular.
However, epidemiological and prospective data
support a long-term influence of early metabolic
control on clinical outcomes. This phenomenon has
recently been defined as 'metabolic memory'. Potential
mechanisms for propagating this 'memory'
are the non-enzymatic glycation of cellular proteins
and lipids, and an excess of cellular reactive oxygen
and nitrogen species, in particular originated at the
level of glycated-mitochondrial proteins, perhaps
acting in concert with one another to maintain stress
signalling. Furthermore, the emergence of this 'metabolic
memory' suggests the need for very early
aggressive treatment aiming to 'normalize' glycaemic
control and the addition of agents which reduce
cellular reactive species and glycation in order to
minimize long-term diabetic complications
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
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