Role of dietary proteins and peptides in cardiovascular disease

Cardiovascular disease (CVD) is the leading cause of death for both men and women in the United States and most other countries. Therefore, a disease of such wide-ranging impact calls for the development of multiple viable strategies for prevention. Diet plays an important role in the development of the major risk factors of CVD such as low-grade systemic inflammation, hypertension, obesity, diabetes and atherosclerosis, the most significant. Thus, diet-based methods of prevention would not only be more feasible, but ultimately more cost-effective than relying on drugs to combat this condition. In recent years, peptides derived from either animal or plant sources have been found to have various bioactive properties. Nevertheless, their potential impact on inflammation and prevention of atherosclerosis has not been fully explored, particularly at the molecular level. In this review, the most current scientific information from in vitro, in vivo and clinical studies on the role of dietary proteins and peptides on CVD has been summarized and discussed.

Antitumor effect of orlistat, a fatty acid synthase inhibitor, is via activation of caspase-3 on human colorectal carcinoma-bearing animal

We established a HT-29/tk-luc human colorectal carcinoma-bearing animal model for the study of the inhibition effect and mechanism of orlistat, a fatty acid synthase (FASN) inhibitor. The results showed that orlistat caused cell cycle arrest at G1 phase, and triggered apoptosis through caspase-3 activation. The tumor inhibition effect of orlistat may also due to the inhibition of fatty acid synthesis without altering FASN activity. The tumor size of orlistat-treated mice in vivo was significantly smaller than that of the controls with 55% inhibition. The therapeutic efficacy was further confirmed with the bioluminescent imaging and nuclear molecular imaging with ¹³¹I-FIAU/gamma scintigraphy and ¹¹C-acetate/microPET. We suggest that FASN is a potential target for the treatment of human colorectal carcinoma.

De novo lipogenesis maintains vascular homeostasis through endothelial nitric-oxide synthase (eNOS) palmitoylation

Endothelial dysfunction leads to lethal vascular complications in diabetes and related metabolic disorders. Here, we demonstrate that de novo lipogenesis, an insulin-dependent process driven by the multifunctional enzyme fatty-acid synthase (FAS), maintains endothelial function by targeting endothelial nitric-oxide synthase (eNOS) to the plasma membrane. In mice with endothelial inactivation of FAS (FASTie mice), eNOS membrane content and activity were decreased. eNOS and FAS were physically associated; eNOS palmitoylation was decreased in FAS-deficient cells, and incorporation of labeled carbon into eNOS-associated palmitate was FAS-dependent. FASTie mice manifested a proinflammatory state reflected as increases in vascular permeability, endothelial inflammatory markers, leukocyte migration, and susceptibility to LPS-induced death that was reversed with an NO donor. FAS-deficient endothelial cells showed deficient migratory capacity, and angiogenesis was decreased in FASTie mice subjected to hindlimb ischemia. Insulin induced FAS in endothelial cells freshly isolated from humans, and eNOS palmitoylation was decreased in mice with insulin-deficient or insulin-resistant diabetes. Thus, disrupting eNOS bioavailability through impaired lipogenesis identifies a novel mechanism coordinating nutritional status and tissue repair that may contribute to diabetic vascular disease.