The hepatic low-density lipoprotein receptor (LDLR) pathway is essential for clearing circulating LDL-cholesterol (LDL-C). While the transcriptional regulation of LDLR is well-characterized, the post-transcriptional mechanisms which govern LDLR expression are just beginning to emerge. Here, we developed a high-throughput genome-wide screening assay to systematically identify microRNAs (miRNAs) that regulate LDLR activity in human hepatic cells. From this screen, we characterize miR-148a as a negative regulator of LDLR expression and activity, and define a novel SREBP1-mediated pathway by which miR-148a regulates LDL-C uptake. Importantly, inhibition of miR-148a increases hepatic LDLR expression and decreases plasma LDL-C in vivo. We also provide evidence that miR-148a regulates hepatic ABCA1 expression and circulating HDL-C levels. Collectively, these studies uncover miR-148a as an important regulator of hepatic LDL-C clearance through direct regulation of LDLR expression, and demonstrate the therapeutic potential of inhibiting miR-148a to ameliorate the elevated LDL-C/HDL-C ratio, a prominent risk factor for cardiovascular disease.

SUMMARY The accumulation of LDL-derived cholesterol in the artery wall is the initiating event that causes atherosclerosis. However, the mechanisms that lead to the initiation of atherosclerosis are still poorly understood. Here, by using endothelial cell-specific transgenesis of the caveolin-1 (Cav-1) gene in mice, we show the critical role of Cav-1 in promoting atherogenesis. Mice were generated lacking Cav-1 and apoE but expressing endothelial-specific Cav-1 in the double knockout background. Genetic ablation of Cav-1 on an apoE knockout background inhibits the progression of atherosclerosis while re-expression of Cav-1 in the endothelium promotes lesion expansion. Mechanistically, the loss of Cav-1 reduces LDL infiltration into the artery wall, promotes nitric oxide production and reduces the expression of leukocyte adhesion molecules, effects completely reversed in transgenic mice. In summary, this unique model provides physiological evidence supporting the important role of endothelial Cav-1 expression in regulating the entry of LDL into the vessel wall and the initiation of atherosclerosis.

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The antipsychotic actions of classic neuroleptics (typical or fi rst-generation antipsychotics, FGA) revolutionized the therapy of schizophrenia, but their extensive use has been impeded by side effects, such as extrapyramidal symptoms, and a high incidence of nonresponders. FGAs, such as haloperidol, act predominantly by blocking dopamine D 2 receptors ( 1 ). Atypical or second-generation antipsychotics (SGA) display relatively weaker antagonism of dopamine D 2 receptors but potent antagonism to serotonin 5-HT 2A receptors ( 1 ). The therapeutic use of SGAs has reduced concern on neurological side effects, but they are not free of metabolically adverse effects. An increase in body weight is fairly rapid after initiating treatment with these drugs. At long term, this may result in overt obesity, along with dyslipidemia, insulin resistance, abnormal glucose tolerance, and diabetes ( 2-4 ). Dyslipidemia is commonly manifested as an increase in total triglyceride and a decrease of high-density lipoprotein (HDL)-cholesterol plasma

This paper examines the in vitro transepithelial transport of antihypertensive peptides derived from egg proteins using Caco-2 cell monolayers. Ovokinin (FRADHPFL) was absorbed intact through the Caco-2 cell epithelium, although it was also susceptible to the action of brush-border aminopeptidases that yielded shorter fragments prior to their transport. The tripeptide YPI was resistant to cellular peptidases and transported through the monolayer, what suggests that the reduction in systemic blood pressure caused by this peptide may be mediated by effects at tissue level. Its pathway for transepithelial absorption was examined using inhibitors of the different mechanisms for oligopeptide transport in the intestinal tract. The main route involved in the transepithelial flux of YPI is probably the peptide H(+)-coupled transporter PepT1. These results highlight the potential of antihypertensive peptides to be used in the formulation of functional foods.

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Background-Atherosclerosis is driven by synergistic interactions between pathological biomechanical, inflammatory and lipid metabolic factors. Our previous studies demonstrated that absence of caveolin-1 (Cav1)/caveolae in hyperlipidemic mice strongly inhibits atherosclerosis, which was attributed to activation of endothelial nitric oxide synthase (eNOS) and increased production of nitric oxide (NO), reduced inflammation and low-density lipoprotein (LDL) trafficking. However, the contribution of eNOS activation and NO production in the athero-protection of Cav1 and the exact mechanisms by which Cav1/caveolae controls the pathogenesis of diet-induced atherosclerosis are still not clear. Methods-Triple knockout mouse lacking expression of eNOS, Cav1 and Ldlr were generated to explore the role of NO production in Cav1-dependent atheo-protective function. The effects of Cav1 on lipid trafficking, extracellular matrix (ECM) remodeling and vascular inflammation were studied both in vitro and in vivo using a mouse model of diet-induced atherosclerosis. The expression of Cav1 and distribution of caveolae regulated by flow were analyzed by immunofluorescence staining and transmission electron microscopy. Results-We found that absence of Cav1 significantly suppressed atherogenesis in Ldlr −/− eNOS −/− mice, demonstrating that athero-suppression is independent of increased NO production. Instead, we find that absence of Cav1/caveolae inhibited LDL transport across the endothelium, pro-atherogenic fibronectin deposition, and disturbed flow-mediated endothelial cell (EC) inflammation. Consistent with the idea that Cav1/caveolae may play a role in early flowdependent inflammatory priming, distinct patterns of Cav1 expression and caveolae distribution were observed in athero-prone and athero-resistant areas of the aortic arch even in wild-type mice. Conclusions-The above findings support a role for Cav1/caveolae as a central regulator of atherosclerosis that links biomechanical, metabolic and inflammatory pathways independent of endothelial eNOS activation and NO production.

Diane(35) Diario appears to be superior to metformin for the control of hyperandrogenism and for the restoration of menstrual regularity in PCOS patients, and it is not associated with any clinically relevant worsening in the classic metabolic cardiovascular risk profile of these women.