# Bioactive Compounds and Nanodelivery Perspectives for Treatment of Cardiovascular Diseases
## 5 Nano-Delivery Systems of Bioactive Compounds  
The nano-delivery method allows for the regulation of food bio-active components' stability, solubility, and bioavailability, and it also maintains their targeted and controlled release. Food safety is a major issue because the usage of nano-delivery for food and drug delivery has grown in popularity [149; 150; 151; 152]. Nano-delivery is carried out in two different ways: liquid and solid. Nano-emulsions, nano-liposomes, and nano-polymerases are the three different forms of liquid nano-delivery systems. Nano-liposomes are divided into SLVs (single lamellar vesicles) and MLVs (multilamellar large vesicles). Nanoparticles, polymeric nanoparticles, and nanocrystals are the three forms of solid nano-delivery systems. Solid lipid nanoparticles (SLNS) and nano-structured lipid carriers (NLCS) are two types of lipid particles. Polymeric nano-particles are of two different types, i.e., nano-spheres and nano-capsules. The types of nano-delivery system are presented in Figure 2.  
Due to chemical and enzymatic barriers and the poor solubility of compounds in the GI tract, a significant decrease in the quality of orally delivered drugs was noticed. It is well known that the action of bioactive compounds depends upon the extent of the bioaccessibility and bioavailability to the organism. There are several conventional drug carrier systems currently used for the effective delivery of cardioprotective drugs, either as oral tablets, parenteral/intravenous administration, or transdermal patches. However, some CVD treatments such as medications against angina pectoris (nitrates, calcium channel blockers, \(\beta\) blockers) produce significant adverse effects such as rash, constipation, nausea, drowsiness, edema, low blood pressure, or headache [153]. In this context, nanotechnology plays a determinant role by manipulating bioactive compounds encapsulated into nano-carriers with dimensions of 1-100 nm, providing a longer half-life, longer circulation time, longer mean residence time, and better pharmacokinetic clearance from the body [154]. These systems particularly depend on physicochemical factors that will influence their absorption, distribution, metabolism, and excretion, which are critical for administering bio-active compounds with improved in vivo results [155]. As the high surface to volume ratio of nanoparticles allows the conjugation, absorption, or encapsulation of bioactive molecules for delivery to the target site, drug delivery vehicles  
Figure 1: CVD risk factors: pathophysiology and beneficial bioactive compounds to reduce the risk factors. are successfully employed owing to their ability to deliver poorly soluble or highly toxic drugs to the target areas. Nanoparticles bind to the gut mucosa and epithelial cells, enter the bloodstream, and then are distributed to tissues and organs such as the liver, kidneys, spleen, heart, lungs, and brain. Nanoparticles and their metabolites are mainly excreted into the liver, kidneys, and colon [156,157]. Nowadays, conventional synthetic drugs are less present in practice owing to their costs and associated complications and side effects, while natural products have received much attention, as they are affordable for the majority of the population and possess multi-targeted effects with fewer side effects than synthetic drugs. It is well known that polyphenols exhibit high antioxidant and anti-inflammatory properties, which are important for certain pathological conditions, including cardiovascular disease. Polyphenol consumption has been shown to improve endothelial function, blood pressure, and platelet function as well as the regulation of cellular processes such as inflammation and NO synthesis in vitro and in vivo [158]. The antioxidant mechanism is attributed to their ability to scavenge free oxygen and nitrogen species and to stimulate the expression of antioxidant enzymes (catalase, superoxide dismutase).