Insulin has been available for the treatment of diabetes for almost a century, and the variety of insulin choices today represents many years of discovery and innovation. Insulin has gone from poorly defined extracts of animal pancreata to pure and precisely controlled formulations that can be prescribed and administered with high accuracy and predictability of action. Modifications of the insulin formulation and of the insulin molecule itself have made it possible to approximate the natural endogenous insulin response. Insulin and insulin formulations had to be designed to produce either a constant low basal level of insulin or the spikes of insulin released in response to meals. We discuss how the biochemical properties of endogenous insulin were exploited to either shorten or extend the time-action profiles of injectable insulins by varying the pharmacokinetics (time for appearance of insulin in the blood after injection) and pharmacodynamics (time-dependent changes in blood sugar after injection). This has resulted in rapid-acting, short-acting, intermediate-acting, and long-acting insulins, as well as mixtures and concentrated formulations. An understanding of how various insulins and formulations were designed to solve the challenges of insulin replacement will assist clinicians in meeting the needs of their individual patients.

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The specific role of dietary fat in breast cancer progression is unclear, although a low-fat diet was associated with decreased recurrence of estrogen receptor alpha negative (ER(-)) breast cancer. ER(-) basal-like MDA-MB-231 and MDA-MB-436 breast cancer cell lines contained a greater number of cytoplasmic lipid droplets compared to luminal ER(+) MCF-7 cells. Therefore, we studied lipid storage functions in these cells. Both triacylglycerol and cholesteryl ester (CE) concentrations were higher in the ER(-) cells, but the ability to synthesize CE distinguished the two types of breast cancer cells. Higher baseline, oleic acid- and LDL-stimulated CE concentrations were found in ER(-) compared to ER(+) cells. The differences corresponded to greater mRNA and protein levels of acyl-CoA:cholesterol acyltransferase 1 (ACAT1), higher ACAT activity, higher caveolin-1 protein levels, greater LDL uptake, and lower de novo cholesterol synthesis in ER(-) cells. Human LDL stimulated proliferation of ER(-) MDA-MB-231 cells, but had little effect on proliferation of ER(+) MCF-7 cells. The functional significance of these findings was demonstrated by the observation that the ACAT inhibitor CP-113,818 reduced proliferation of breast cancer cells, and specifically reduced LDL-induced proliferation of ER(-) cells. Taken together, our studies show that a greater ability to take up, store and utilize exogenous cholesterol confers a proliferative advantage to basal-like ER(-) breast cancer cells. Differences in lipid uptake and storage capability may at least partially explain the differential effect of a low-fat diet on human breast cancer recurrence.

We previously described a lipid-accumulating phenotype of estrogen receptor negative (ER(-)) breast cancer cells exemplified by the MDA-MB-231 and MDA-MB-436 cell lines. These cells had more lipid droplets, a higher uptake of oleic acid and LDL, a higher ratio of cholesteryl ester (CE) to triacylglycerol (TAG), and higher expression of acyl-CoA:cholesterol acyltransferase 1 (ACAT1) as compared to ER(+) MCF-7 breast cancer cells. LDL stimulated proliferation of ER-cells only, and proliferation was reduced by inhibition of ACAT. We hypothesized that storage of exogenous lipids would confer an energetic advantage. We tested this by depriving cells of exogenous lipids and measuring chemotactic migration, an energy-intensive behavior. MDA-MB-231 cells were grown for 48 h in medium with either 5% FBS or 5% lipoprotein-depleted (LD) FBS. Growth in LD medium resulted in visibly reduced lipid droplets and an 85% decrease in cell migration. Addition of LDL to the LD medium dose-dependently restored the ability to migrate in an ACAT-sensitive manner. LDL receptor (LDLR) mRNA was 12-fold higher in MDA-MB-231 cells compared to nontumorigenic ER-MCF-10A breast epithelial cells grown in LD medium. Addition of LDL to the LD medium reduced LDLR mRNA levels in MCF-10A cells only. We asked if ACAT1 activity was associated with the expression of the LDLR in MDA-MB-231 cells. LDLR mRNA in MDA-MB-231 cells was substantially reduced by inhibition of ACAT, demonstrating that high ACAT1 activity permitted higher LDLR expression. This data substantiates the association of lipid accumulation with aggressive behavior in an ER-breast cancer cell line.

AimsTo compare the efficacy and safety of basal insulin peglispro (BIL), which has a flat pharmacokinetic and pharmacodynamic profile and a long duration of action, with insulin glargine (GL) in patients with type 1 diabetes.Materials and methodsIn this phase III, 52‐week, blinded study, we randomized 1114 adults with type 1 diabetes in a 3 : 2 distribution to receive either BIL (n = 664) or GL (n = 450) at bedtime, with preprandial insulin lispro, using intensive insulin management. The primary objective was to compare glycated haemoglobin (HbA1c) in the groups at 52 weeks, with a non‐inferiority margin of 0.4%.ResultsAt 52 weeks, mean (standard error) HbA1c was 7.38 (0.03)% with BIL and 7.61 (0.04)% with GL {difference −0.22% [95% confidence interval (CI) −0.32, −0.12]; p < 0.001}. At 52 weeks more BIL‐treated patients reached HbA1c <7% (35% vs 26%; p < 0.001), the nocturnal hypoglycaemia rate was 47% lower (p < 0.001) and the total hypoglycaemia rate was 11% higher (p = 0.002) than in GL‐treated patients, and there was no difference in severe hypoglycaemia rate. Patients receiving BIL lost weight, while those receiving GL gained weight [difference −1.8 kg (95% CI −2.3, −1.3); p < 0.001]. Treatment with BIL compared with GL at 52 weeks was associated with greater increases from baseline in levels of serum triglyceride [difference 0.19 mmol/l (95% CI 0.11, 0.26); p < 0.001] and alanine aminotransferase (ALT) levels [difference 6.5 IU/l (95% CI 4.1, 8.9), p < 0.001], and more frequent injection site reactions.ConclusionsIn patients with type 1 diabetes, treatment with BIL compared with GL for 52 weeks resulted in a lower HbA1c, more patients with HbA1c levels <7%, and reduced nocturnal hypoglycaemia, but more total hypoglycaemia and injection site reactions and higher triglyceride and ALT levels.

Ascites in epithelial ovarian cancer (EOC) promotes tumor development by mechanisms that are incompletely understood. Lysophosphatidic acid (LPA), a major tumor-promoting factor in EOC ascites, is an enzymatic product of autotaxin (ATX) and phospholipase A(2) (PLA(2))enzymes. The contribution of PLA(2) activities to ovarian tumorigenesis was investigated. The quantitative measurement of PLA(2) activities in ascites and tissues, as well as assay conditions selective for PLA(2) subtypes, were optimized and validated. PLA(2) activities correlated with tumor-promoting activates in cell-based and in vivo assays. High activities consistent with both cytosolic and calcium-independent PLA(2) were found in human EOC ascites for the first time. Elevated PLA(2) and ATX activities were also observed in EOC compared to benign tumors and normal tissues. Cell-free and vesicle-free (S4) human EOC ascites potently promoted proliferation, migration, and invasion of human EOC cells in a PLA(2)-dependent manner. LPA mediated a significant part of the cell-stimulating effects of ascites. S4 ascites stimulated tumorigenesis/metastasis in vivo, and methyl arachidonyl fluorophosphonate was highly effective in inhibiting EOC metastasis in mouse xenograft models. PLA(2) activity was found in conditioned media from both EOC cells and macrophages. Collectively, our work implies that PLA(2) activity is a potential marker and therapeutic target in EOC.

AimsTo evaluate the efficacy and safety of basal insulin peglispro (BIL) with those of insulin glargine, both in combination with prandial insulin lispro, in patients with type 2 diabetes (T2D).MethodsIn this phase III, multicentre, double‐blind, 26‐week study, we randomized patients with T2D [glycated haemoglobin (HbA1c) ≥7 and <12%, on ≥1 insulin injections daily) to BIL (n = 691) or glargine (n = 678), in combination with lispro.ResultsAt week 26, the primary objective of non‐inferiority of BIL versus glargine for HbA1c reduction was achieved (least squares mean difference −0.21%; 95% confidence interval −0.31 to −0.11%), with statistical superiority of BIL with multiplicity adjustment (p < 0.001). HbA1c at baseline was 8.4% versus 8.5% for BIL versus glargine and at 26 weeks it was 6.8% versus 7.0%. At 26 weeks, more patients reached HbA1c <7% with BIL than with glargine (63.3% vs 53.3%; p < 0.001), the nocturnal hypoglycaemia rate (≤3.9 mmol/l) was lower with BIL (0.51 vs 0.92 events/30 days; p < 0.001), but the daytime hypoglycaemia rate was higher with BIL (5.47 vs 4.53 events/30 days; p < 0.001). The total hypoglycaemia relative rate was 1.10 (p = 0.053). At 26 weeks, patients in the BIL group had lower fasting serum glucose levels, higher basal insulin dosing, with no statistically significant difference in prandial or total insulin dosing, reduced glucose variability and less weight gain (1.3 kg vs 2.2 kg) compared with the glargine group. The BIL group had higher mean triglyceride and aminotransferase levels.ConclusionsIn patients with T2D, BIL with insulin lispro provided greater improvement in glycaemic control with less nocturnal hypoglycaemia, lower glucose variability and less weight gain compared with glargine. The daytime hypoglycaemia rate and mean triglyceride and aminotransferase levels were higher with BIL.

Epidemiological data indicate that there is a strong association between intake of trans-18 : 2 fatty acids (TFA) and sudden cardiac death. There is little known about the mechanisms by which TFA exert harmful effects on the cardiovascular system. The present in vitro study is the first to demonstrate the effects of membrane-incorporated C18 : 2 TFA on human aortic endothelial cell (HAEC) function. Trans-18 : 2 fatty acids were incorporated to a greater extent (2-fold) in the phospholipid fraction of endothelial cells than that of cis-18 : 2; furthermore, these fatty acids were enriched to a similar extent in the TAG fraction. Flow cytometric analysis indicated that TFA treatment of HAEC significantly increased the expression of endothelial adhesion molecules, including intercellular adhesion molecule-1 (CD54) and vitronectin receptor (CD51/CD61). Incorporation of TFA into membranes increased HAEC adhesion to fibronectin-or vitronectin-coated plates by 1·5-to 2-fold, respectively. Neutrophil and monocyte adhesion to HAEC monolayers was nearly proportional to adhesion molecule expression. TFA treatment also induced the release of monocyte chemoattractant protein-1 by nearly 3-fold in non-stimulated HAEC. Furthermore, we examined the role of TFA on in vitro angiogenic assays. Chemotactic migration of TFA-treated HAEC toward sphingosine-1-phosphate (SPP) was significantly increased compared with controls. Conversely, capillary morphogenesis of TFA-treated HAEC was significantly inhibited in response to SPP, suggesting that TFA incorporation suppresses endothelial cell differentiation. In conclusion, these in vitro studies demonstrated that TFA play a role in the induction of pro-inflammatory responses and endothelial cell dysfunction.Endothelial cells: Trans-fatty acids: Adhesion molecules: Chemotaxis: Capillary morphogenesis After the first successful hydrogenation of oils in 1897, the proportional intake of trans isomers of unsaturated fatty acids has dramatically risen in the human diet 1 . Trans-fatty acid consumption is estimated to contribute 4-12 % of the total dietary fat intake in the US population, which corresponds to 13 g trans-fatty acids/person per d at the higher intake 2 . Unlike Western diets, traditional diets in Korea and Japan contain relatively small quantities of trans-fatty acids, with estimates in the range of 0·1 -0·6 g/person per d 3 . Trans-fatty acids occur naturally at relatively low levels in meat and dairy products as a by-product of fermentation in ruminant animals 1 . The majority of trans-fatty acids in the diet are trans-8 : 1, which is derived from the partial hydrogenation of oils 4 . However, the process of heating vegetable oils during deodorisation, and frying or baking food in vegetable oils results in the generation of trans-18 : 2 5 . The elevated temperature in these processes causes the conversion of cis double bonds to trans isomers.The effect of increased trans-fatty acid consumption has been linked to a variety of afflictions, most notably CHD. Numerous epidemiologica...