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BACKGROUND: While low sodium intake (40 years with stable blood pressure (BP), without heart failure or postural hypotension were randomised to intensive dietary counselling (target sodium intake

Introduction Adrenocortical carcinoma (ACC) is a rare aggressive cancer with low overall survival. Adjuvant mitotane improves survival but is limited by poor response rates and resistance. Mitotane’s efficacy is attributed to the accumulation of toxic free cholesterol, predominantly through cholesterol storage inhibition. However, targeting this pathway has proven unsuccessful. We hypothesize that mitotane-induced free-cholesterol accumulation is also mediated through enhanced breakdown of lipid droplets. Methodology ATCC-H295R (mitotane-sensitive) and MUC-1 (mitotane-resistant) ACC cells were evaluated for lipid content using specific BODIPY dyes. Protein expression was evaluated by immunoblotting and flow cytometry. Cell viability was measured by quantifying propidium iodide-positive cells following mitotane treatment and pharmacological inhibitors of lipolysis. Results H295R and MUC-1 cells demonstrated similar neutral lipid droplet numbers at baseline. However, evaluation of lipid machinery demonstrated distinct profiles in each model. Analysis of intracellular lipid droplet content showed H295R cells preferentially store cholesteryl esters, whereas MUC-1 cells store triacylglycerol. Decreased lipid droplets were associated with increased lipolysis in H295R and in MUC-1 at toxic mitotane concentrations. Pharmacological inhibition of lipolysis attenuated mitotane-induced toxicity in both models. Conclusion We highlight that lipid droplet breakdown and activation of lipolysis represent a putative additional mechanism for mitotane-induced cytotoxicity in ACC. Further understanding of cholesterol and lipids in ACC offers potential novel therapeutic exploitation, especially in mitotane-resistant disease.

The rupture of atherosclerotic plaques is the prerequisite for adverse cardiovascular events. Calcification morphology plays a critical role in plaque stability, therefore accurate calcification classification is essential for favourable patient management. Blood biomarkers may be a worthwhile approach to stratify patients based on calcification phenotype. Vitamin K-dependent Matrix γ-carboxyglutamate (Gla) protein (MGP) is a potent inhibitor of vascular calcification. Recent studies have demonstrated the potential utility of circulating non-functional MGP (dp-ucMGP) measurements to determine arterial stiffness and calcification levels. The objective of this study was to examine the relationship between circulating dp-ucMGP and calcification phenotype within symptomatic atherosclerotic lesions. Consenting patients undergoing standard endarterectomy procedures were recruited (n = 29). Fasting venous blood was collected preoperatively. Circulating plasma levels of dp-ucMGP were quantified using the inaKtif MGP (dp-ucMGP) iSYS kit. A bicinchoninic acid assay was used to standardise the total protein content present in each sample. High-resolution micro-CT imaging was conducted on the excised atherosclerotic specimens postoperatively. ImageJ post-processing was used to accurately quantify the calcification volume (≥ 130 Hounsfield Units) and determine the total number of calcified particles (3D objects counter plugin). Thirteen carotid (average age 71 years, 9 male) and fourteen peripheral lower limb (average age 65 years, 12 male) patients were examined. One patient had a carotid and a peripheral lower limb plaque (age 79, male). Peripheral lower limb specimens have larger volumes of calcification and higher numbers of calcified particles than carotid samples (472 ± 310 vs 85 ± 113mm3, p < 0.0005; 13919 ± 16034 vs 3476 ± 6208, p = 0.061.) While a higher dp-ucMGP value was noted in carotid than peripheral lower limb patients (214 ± 52 vs 169 ± 36pmol/L, p = 0.014) there was no correlation between circulating dp-ucMGP and calcification volume or number of calcified particles (rs = -0.329 and rs = 0.046). Previous research also found that peripheral lower limb lesions contain higher volumes of calcification than carotid lesions. There is currently no published data on calcified particle comparisons. Patients with symptomatic carotid disease are assumed to have a degree of peripheral arterial disease, this could explain the higher levels of circulating dp-ucMGP in carotid patients. The current study did not examine the dietary patterns of individuals with regards to Vitamin K intake or analyse other areas of the vasculature for additional calcification. This may interfere with dp-ucMGP measurements. This study serves as a preliminary investigation into the potential of dp-ucMGP as a blood based biomarker to distinguish between symptomatic atherosclerotic calcification phenotypes.

There is limited information on reference values for lipids and lipoproteins in an Irish population. In this observational study, we have described the distributions of lipids in a large Irish cohort.Over 110,000 lipid profiles were selected from a database of almost 1.5 million consecutive lipid profiles performed in the Clinical Biochemistry Laboratory in University Hospital Galway between 2004 and 2017 to best represent the Irish population. Age- and sex-related reference intervals for both sexes for total cholesterol, triglycerides, HDL cholesterol and LDL cholesterol, from the age of ten to greater than 90 years, were determined. Two methods for estimating LDL cholesterol were also compared.Sex-related differences in lipid distributions arise before the age of 20 years and are life-long. In both sexes total and LDL cholesterol levels gradually increased towards middle age with a decrease towards old age. Levels tended to be higher in males than in females up to mid-life at which stage they cross over with females having on average higher levels. The median of the triglyceride distributions show similar age- and sex-related changes to total cholesterol, but the distributions show a very marked positive skew that is particularly obvious in middle aged males. HDL cholesterol distributions change little throughout life with males having lower levels than females. Changing from the Friedewald formula to that proposed by Martin would impact the management of some patients with dyslipidaemia.This study provides lipid reference values for clinical biochemistry laboratories and clinicians working in Ireland. It is informative for public health initiatives wishing to target dyslipidaemia as a modifiable risk for cardiovascular disease and for investigators researching geographical and temporal variances in lipid parameters.