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The purpose of this paper is to analyze the influence of curvature on the transport of low-density lipoprotein (LDL) through a curved artery and concentration boundary layer characteristics numerically.

By using a projection method based on the second-order central difference discretization, the authors solve the set of governing equations, which consists of Navier–Stokes, continuity and species transport. The effects of initial straight length, as well as the curvature and wall shear stress (WSS) on LDL transport in a curved artery are established in this paper.

The obtained numerical results imply that the LDL concentration boundary layer thickness decreases in the outer part of the curved artery and increases in the inner part for both with or without initial straight length. The effect of Reynolds number on the concentration distribution in a curved artery with initial straight length is more pronounced than that on a fully curved artery, although an opposite trend was seen for the curvature ratio. The maximum surface LDL concentration is related to the regions with minimum WSS in the inner part of the curved artery, which has more potential the formation of atherosclerosis.

The authors present a comprehensive concentration distribution of LDL in the concentration boundary layer of the curved artery. The authors also characterize and predict the influence of curvature on the formation and development of atherosclerosis within the arterial wall.

This study aims to investigate a critical review on the applications of fluid-structure interaction (FSI) in porous media.

Transport phenomena in porous media are of continuing interest by many researchers in the literature because of its significant applications in engineering and biomedical sectors. Such applications include thermal management of high heat flux electronic devices, heat exchangers, thermal insulation in buildings, oil recovery, transport in biological tissues and tissue engineering. FSI is becoming an important tool in the design process to fully understand the interaction between fluids and structures.

This study is structured in three sections: the first part summarizes some important studies on the applications of porous medium and FSI in various engineering and biomedical applications. The second part focuses on the applications of FSI in porous media as related to hyperthermia. The third part of this review is allocated to the applications of FSI of convection flow and heat transfer in engineering systems filled with porous medium.

To the best knowledge of the present authors, FSI analysis of turbulent flow in porous medium never been studied, and therefore, more attention should be given to this area in any future studies. Moreover, more studies should also be conducted on mixed convective flow and heat transfer in systems using porous medium and FSI.

The wall of the blood vessel is considered as a flexible multilayer porous medium, and therefore, rigid wall analysis is not accurate, and therefore, FSI should be implemented for accurate predictions of flow and hemodynamic stresses.

The use of porous media theory in biomedical applications received a great attention by many investigators in the literature (Khanafer and Vafai, 2006a; Al-Amiri et al., 2014; Lasiello et al., 2016a, Lasiello et al., 2016b; Lasiello et al., 2015; Chung and Vafai, 2013; Mahjoob and Vafai, 2009; Yang and Vafai, 2008; Yang and Vafai, 2006; Ai and Vafai, 2006). A comprehensive review was conducted by Khanafer and Vafai (2006b) summarizing various studies associated with magnetic field imaging and drug delivery. The authors illustrated that the tortuosity and porosity had a profound effect on the diffusion process within the brain. AlAmiri et al. (2014) conducted a numerical study to investigate the effect of turbulent pulsatile flow and heating technique on the thermal distribution within the arterial wall. The results of that investigation illustrated that local heat flux variation along the bottom layer of the tumor was greater for the low-velocity condition. Yang and Vafai (2006) presented a comprehensive four-layer model to study low-density lipoprotein transport in the arterial wall coupled with a lumen (Figure 1). All the four layers (endothelium, intima, internal elastic lamina and media) were modeled as a homogenous porous medium.

Future studies on the applications of FSI in porous media are recommended in this review.

“Streets broad and narrow”. In terms of shops and retail trade, it was always the narrow streets of town centres which attracted the trade, although the shops were small cramped for space, but always a cosy, friendly air. Few ever became vacant and although interspersing chain shops seemed to break the rhythm, most were privately owned, run through the years by generations of the same family. The shops removed the proverbial meanness of narrow streets; the lights, the shopping crowds, especially on Saturday nights; shop frontmen bawling their prices, the new boys calling the late editions—all this made shopping an attractive outing; it still does. There were the practical advantages of being able to cross and re‐cross the street, with many shops on both sides within the field of vision. The broad highway had none of these things and it was extremely rare for shops to exist both sides of the street, and still less to flourish. It is much the same to this day. Hygiene purists would find much to fault, but it was what the public wanted and curiously, there was very little food poisoning; it would be untrue to say outbreaks never occurred but they were extremely rare.

Cholesterol is one of the most talked about substances in modern nutrition. This is due to the publicity given by the media to the relation between plasma cholesterol levels and coronary heart disease. However, the properties of cholesterol itself are less widely known, and this article seeks to describe some of its characteristics.

The purpose of this study was to determine the effects of chickpea (Cicer arietinum) protein hydrolysates prepared at two degrees of hydrolysis (DH) on lipoprotein profile and on oxidant status in cholesterol-fed rats.

Eighteen male Wistar rats (220 ± 10 g) were divided into three groups and fed for 30 days a diet containing 20 per cent casein supplemented with 1 per cent cholesterol and 0.5 per cent cholic acid. During the experimentation, the first and the second groups received daily by gavage 250 mg of chickpea protein hydrolysates/rat at DH = 8 per cent (CPH8) and DH = 17 per cent (CPH17), respectively. The third group, named control group (CG), received water under the same conditions.

Serum total cholesterol concentrations were reduced in CPH8 (p < 0.0073) and CPH17 (p < 0.0004) groups versus CG. This reduction corresponded to a lower very-low-density lipoprotein (VLDL)-cholesterol (p < 0,0019). CPH17 reduced low-density lipoprotein- and high-density lipoprotein (HDL)-cholesterol (p < 0.0001) but increased apolipoprotein A4 (p < 0.002) concentrations and lecithin-cholesterol acyltransferase activity (p < 0.0001). APOA1 remained unchanged in the treated groups. Liver total and esterified cholesterol contents were twofold lower in both treated groups versus CG. CPH8 increased triacylglycerols and phospholipids (p < 0.0001) contents, while CPH17 decreased those of unesterified cholesterol (p < 0.0016). Compared with CG, CPH8 and CPH17 reduced serum (p < 0.0001) and lipoprotein hydroperoxides by stimulating paraoxonase activity (p < 0.0001). However, only CPH17 treatment reduced serum, VLDL- and HDL-malondialdehyde contents and improved glutathione peroxidase activity (p < 0.061).

Thus, chickpea protein hydrolysates and especially hydrolysed at DH = 17 per cent may have a great potential for use as a nutraceutical to reduce hypercholesterolaemia and, by consequence, oxidative stress. Therefore, the degree of enzymatic hydrolysis has a significant influence on the production of potent bioactive peptides.

This paper aims to evaluate the protective potential of prickly pear cactus fresh cladodes (opuntia ficus indica (OFI)) on glycemic disorders, dyslipidemia, prooxidant/antioxidant stress biomarkers and reverse cholesterol transport (by evaluating the activity of lecithin-cholesterol acyltransferase (LCAT)) and paraoxonase (PON1) in rats prematurely exposed to cafeteria diet (CD).

Sixteen young rats were divided into two groups fed CD containing 50 per cent of hyperlipidic diet (HLD) and 50 per cent of junk food mix supplemented or not with 50 g of fresh young cladodes of OFI to 100 g of CD, during 30 days.

OFI cladodes supplementation decreased significantly body weight (p < 0.001), food intake (p < 0.05), adipose tissue weight (p < 0.01), fasting glycemia and glycosylated hemoglobin (p < 0.01), homeostasis model assessment (HOMA-IR) and insulinemia (p < 0.001), levels of cholesterol (C) (p < 0.05) and triacylglycerols (TG) (p < 0.01) in serum and in very low-density lipoproteins (VLDL-C p < 0.05 and VLDL-TG p < 0.01) and improves reverse cholesterol transport by increasing high-density lipoprotein cholesteryl-esters concentrations (p < 0.001) and by stimulating LCAT activity. Moreover, they attenuated lipid peroxidation in VLDL and low-density lipoproteins by increasing atheroprotective activity of PON-1 and in liver and adipose tissue by enhancing enzymatic antioxidant defence.

The young cladodes of OFI because of their antiobesity benefits could constitute a novel functional ingredient in pharmaceutical and nutraceutical applications.

Young cladodes of OFI in rat precociously submitted to a hyperlipidic diet/junk food (cafeteria model) seem to prevent metabolic disorders associated with obesity.

The purpose of this study was to evaluate the antioxidant and hypocholesterolemic activities of sardine and bogue protein hydrolysates in cholesterol-fed rats.

In total, 18 male Wistar rats (220 ± 10 g) fed 20 per cent casein, 1 per cent cholesterol and 0.5 per cent cholic acid were divided into three groups and received a daily gavage of 250 mg of sardine (SPH) or bogue (BPH) protein hydrolysates for 30 days. The third group, named control group (CG), received in the same conditions water. Lipoproteins were fractionated by size-exclusion fast protein liquid chromatography, and serum lipids, apolipoproteins and lipoproteins were assayed.

In SPH and BPH groups, serum total cholesterol concentrations were −66 per cent lower than in CG. This corresponded to the decreased very low-density lipoprotein-C in the former groups. Moreover, BPH treatment reduced low-density lipoprotein-C compared with CG and SPH groups. Compared with CG, serum phospholipids were reduced by SPH and BPH. Furthermore, BPH increased significantly APOA4 and sphingomyelin but lowered phosphatidylcholine. In the latter group, serum lecithin cholesterol acyltransferase activity was +23 per cent higher, but with SPH, this activity was −35 per cent reduced compared with CG. Apolipoprotein A-I contents were similar in the three groups. Compared with CG, hydroperoxide and lipid peroxidation contents in serum and lipoprotein fractions were reduced by SPH and BPH. Compared with CG, serum superoxide dismutase and glutathione peroxidase activities were increased in the treated groups, particularly in the BPH group.

These results suggest that sardine protein hydrolysates and particularly those of bogue could be a very useful natural compound to prevent hypercholesterolemia by both improving the lipid profile and modulating oxidative stress in cholesterol-fed rats.

The purpose of this study is to compare the effect of olive or salmon oil on the hepatic storage and transport of fatty acids by very-low-density lipoproteins (VLDL).

In all, 24 male Wistar rats (80 ± 5 g) were fed a 0.5 per cent cholesterol-enriched diet with either 20 per cent casein (C) or chickpea (CP) proteins with 10 per cent olive (O) or salmon (S) oil for 28 days.

In VLDL-triacyglycerols fatty acids, oleic acid content was higher in CPS as compared to that in CS or CPO and lower in CS and CPO than that in CO; linoleic acid content was higher in all groups; arachidonic acid content was higher in CS and CPO as compared to that in CO. In the liver, TG fatty acids content was lower in CPO or CPS as compared to that in CO or CS; oleic and arachidonic acid contents were lower in CPS than that in CPO; linoleic acid content was lower in CS, CPS and CPO than that in CO, CPO and CO. In liver, phospholipid fatty acid, oleic and arachidonic acid contents were lower in CPS than that in CS; oleic, linoleic and arachidonic acid contents were lower in CPO compared to that in CO. In liver, cholesteryl esters fatty acids, oleic, linoleic and arachidonic acids contents were higher in CPS as compared to that in CS; oleic, linoleic and arachidonic acid contents were lower in CS as compared to that in CO; linoleic and arachidonic acid contents were lower in CPS than that in CPO.

A cholesterol-enriched diet containing casein or chickpea proteins combined with olive or salmon oil affects the hepatic storage and transport of polyunsaturated and monounsaturated fatty acids by VLDL.

The purpose of this study was to determine the effects of whole oat, oat bran and refined oat incorporation in a high-fat diet (HFD) on cardio-metabolic risk biomarkers in rats with type 2 diabetes mellitus (T2DM).

T2DM was induced by feeding male rats with an HFD for 10 weeks, followed by a low dose of streptozotocin. T2DM rats were then divided into four homogeneous groups. Three groups consumed an HFD containing 45 per cent (g/100 g diet) whole oat, oat bran or refined oat. The fourth untreated group (control) received the HFD.

The results showed that whole oat and oat bran, compared with refined oat and control, effectively reduced food intake (p < 0.007), arterial blood pressure (p = 0.0001), glycemia (p < 0.001), insulinemia (p < 0.01), glycosylated haemoglobin (p < 0.001) as well as homeostasis insulin resistance (HOMA-IR) (p < 0.001). They also improved blood lipid levels and reverse cholesterol transport by reducing serum total cholesterol (p = 0.0001), triacylglycerols (p < 0.05), very-low- (p = 0.0001) and low-density lipoproteins cholesterol contents (p < 0.02) increasing lipids (p < 0.002) and cholesterol excretion (p = 0.0001), and high-density lipoprotein cholesteryl esters (HDL₂-CE) concentrations (p = 0.0001) and stimulating lecithin: cholesterol acyltransferase (LCAT) activity (p = 0.0001). Moreover, they attenuated lipid peroxidation by increasing paraoxonase-1 (PON-1) atheroprotective activity (p < 0.05).

In T2DM rats, whole oat and particularly, its bran incorporated into an HFD improves arterial blood pressure, glycemic balance and lipid metabolic pathway by reducing hypertriglyceridemia and hypercholesterolemia and increasing atheroprotective activities of LCAT and PON-1. In contrast, refined oat accentuates the risk factors associated with diabetes.

This study aims to examine whether Globularia alypum (Ga) lyophilized aqueous leaves extract treatment improves cardiometabolic syndromes such as hyperglycemia, lipid profiles and oxidative damage resulting from a high-fructose diet induced in hypertriglyceridemic rats.

A total of 24 male Wistar rats weighing 80 ± 5 g were first randomly divided into 2 groups. A total of 12 control rats (C) were fed a standard-diet (St-D) and 12 high fructose (HF) rats were fed a high-fructose diet (HF-D) containing St-D in which cornstarch was substituted by fructose (61.4%). After 15 weeks of feeding, body weight (BW) was about 320 ± 20 g and hypertriglyceridemia was noted in HF vs C group (2.69 ± 0.49 mmol/L) vs (1.25 ± 0.33 mmol/L). Each group of rats was then divided into two equal groups (n = 6) and fed during four weeks either a St-D or HF-D, treated or not with 1% of Ga extract (C-Ga) and (HF-Ga). After 28 days, fasting rats were anesthetized and blood and tissues were removed to measure biochemical parameters.

The results showed no significant differences in BW and insulinemia between all groups. Ga extract supplementation reduced glycemia (−36%), glycosylated hemoglobin (−37%), Homeostasis Model of Assessment-Insulin Resistance index (−34%) and triacylglycerol’s contents in plasma (−33%), very low density lipoproteins–low density lipoproteins (VLDL-LDL) (−48%), liver (−52%) and aorta (−39%); total cholesterol concentrations in aorta was 3.7-fold lower in HF-Ga vs HF group. Ga treatment reduced lipid peroxidation in plasma, VLDL-LDL, red blood cells (RBC), liver, muscle and kidney by improving superoxide dismutase (SOD) activity and glutathione peroxidase (GPx) in RBC and catalase (CAT) activity in kidney (p < 0.05). Moreover, Ga ameliorates glutathione (GSH) production in RBC (+41%) and kidney tissues (+35%).

Ga extract ameliorated cardiometabolic syndrome by its hypotriglyceridemic effect and prevented development of insulin resistance. It reduces lipid peroxidation by enhancing non-enzymatic (GSH) and enzymatic (SOD, GPx and CAT) antioxidant defense systems in high-fructose hypertriglyceridemic rats. Therefore, supplementation of Ga leaves extract as an adjuvant could be used for the treatment of hypertriglyceridemia and the prevention and/or the management of cardio-metabolic adverse effects.