Advances in the management of hyperlipidemia-induced atherosclerosis

The in vivo study on antioxidant activity of wendan decoction in treating hyperlipidemia: a pharmacokinetic-pharmacodynamic (PK-PD) model

Background: Wendan Decoction (WDD) is a six-herb Chinese medicine recipe that was first mentioned in about 652 AD. It is frequently used to treat hyperlipidemic patients' clinical complaints. According to reports, oxidative stress has a significant role in hyperlipidemia. Purpose: There has not yet been a thorough pharmacokinetic-pharmacodynamic (PK-PD) examination of the clinical efficacy of WDD in the context of hyperlipemia-related oxidative stress. Therefore, the goal of this research is to explore the antioxidant essence of WDD by developing a PK-PD model, ordering to assure its implication in treating hyperlipidemia in medical practice. Methods: The model rats of foodborne hyperlipidemia were established by feeding with high-fat feed, and the lipid-lowering effect of WDD was explored. The plasma drug concentration of rats at different doses were measured by UPL-MS/MS technology, and PK parameters were calculated using Phoenix WinNonlin 8.1 software. The level of lipid peroxide (LPO) in plasma at different time points was measured by enzyme labeling instrument. Finally, the PK-PD model was established by using Phoenix WinNonlin 8.1 software, to explore the lipid-lowering effect of WDD and the relation between the dynamic changes of chemical components and antioxidant effect. Results: The findings suggested that, WDD can reduce the levels of triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) in plasma, and high-density lipoprotein cholesterol (HDL-C) was related to the dosage. Between the peak drug levels and the WDD's maximal therapeutic response, there existed a hysteresis. WDD's effect-concentration curves displayed a counterclockwise delaying loop. Alternatively, among the ten components of WDD, hesperetin, quercetin, naringenin and tangeretin might exert more significant effects in regulating the LPO levels in hyperlipidemic rats. Conclusion: This study can be helpful for other investigators to study the lipid-lowering effect of WDD.

Insights into the pivotal role of statins and its nanoformulations in hyperlipidemia

Hyperlipidemia is the primary cause of heart disorders and has been manifested as the condition with remarkable higher levels of very-low-density lipoproteins, low-density lipoproteins, intermediate-density lipoprotein, triglycerides, and cholesterol in blood circulation. Genetic causes or systemic metabolic illnesses like diabetes mellitus, increased alcohol consumption, hypothyroidism, and primary biliary cirrhosis are several reasons behind development of hyperlipidemia. Higher levels of lipids and lipoproteins in plasma are responsible for various health disorders in human body like occlusion of blood vessels, acute pancreatitis, and reduced artery lumen elasticity. Both primary and secondary prophylaxis of heart disease can be achieved through combination of pharmacologic therapy with therapeutic lifestyle adjustments. Statins which belongs to HMG-CoA reductase inhibitors are preferred for primary prevention of hyperlipidemia particularly for individuals at higher risk of development of heart disease. This review discusses the recent advancements and outcomes of nanoparticle drug carriers for statins in the therapy of hyperlipidemia.

Vascular Stem/Progenitor Cells in Vessel Injury and Repair

Vascular repair upon vessel injury is essential for the maintenance of arterial homeostasis and function. Stem/progenitor cells were demonstrated to play a crucial role in regeneration and replenishment of damaged vascular cells during vascular repair. Previous studies revealed that myeloid stem/progenitor cells were the main sources of tissue regeneration after vascular injury. However, accumulating evidences from developing lineage tracing studies indicate that various populations of vessel-resident stem/progenitor cells play specific roles in different process of vessel injury and repair. In response to shear stress, inflammation, or other risk factors-induced vascular injury, these vascular stem/progenitor cells can be activated and consequently differentiate into different types of vascular wall cells to participate in vascular repair. In this review, mechanisms that contribute to stem/progenitor cell differentiation and vascular repair are described. Targeting these mechanisms has potential to improve outcome of diseases that are characterized by vascular injury, such as atherosclerosis, hypertension, restenosis, and aortic aneurysm/dissection. Future studies on potential stem cell-based therapy are also highlighted.

Structural simplification and bioisostere principle lead to Bis-benzodioxole-fibrate derivatives as potential hypolipidemic and hepatoprotective agents

The bis-benzodioxole-fibrate hybrids were designed by structural simplification and bioisostere principle. Lipids lowering activity was preliminarily screened by Triton WR 1339 induced hyperlipidemia mice model, in which T3 showed the best hypolipidemia, decreasing plasma triglyceride (TG) and total cholesterol (TC), which were better than sesamin and fenofibrate (FF). T3 was also found to significantly reduce TG, TC and low density lipoprotein cholesterin (LDL-C) both in plasma and liver tissue of high fat diet (HFD) induced hyperlipidemic mice. In addition, T3 showed hepatoprotective activity, which the noteworthy amelioration in liver aminotransferases (AST and ALT) was evaluated and the histopathological observation exhibited that T3 inhibited lipids accumulation in the hepatic and alleviated liver damage. The expression of PPAR-α receptor involved lipids metabolism in liver tissue significantly increased after T3 supplementation. Other potent activity, such as antioxidation and anti-inflammation, was also observed. The molecular docking study revealed that T3 has good affinity activity toward to the active site of PPAR-α receptor. Based on these findings, T3 may serve as an effective hypolipidemic agent with hepatoprotection.

Co-Delivery of Curcumin and Bioperine via PLGA Nanoparticles to Prevent Atherosclerotic Foam Cell Formation

Cholesterol-rich arterial plaques characterize atherosclerosis, a significant cause of heart disease. Nutraceuticals have received attention over the years, demonstrating potential benefits towards treating and preventing cardiovascular diseases (CVD), including atherosclerosis. Curcumin, a potent polyphenol present in Curcuma longa, has shown remarkable anti-atherosclerotic activity via anti-inflammatory and anti-oxidative properties. The bioavailability and low water solubility of curcumin limit its clinical translational purposes. These issues can be circumvented effectively by nano-drug delivery systems that can target atherosclerotic plaque sites. In this work, we chose to use curcumin and a natural bioenhancer called Bioperine (derived from Piper nigrum) inside a polymeric nano-drug delivery system for targeting atherosclerotic plaque sites. We selected two different ratios of curcumin:Bioperine to study its comparative effect on the inhibition of oxidized low-density lipoprotein (Ox-LDL)-induced foam cell formation. Our studies demonstrated that Cur-Bio PLGA NPs (both ratios) maintained the cell viability in THP-1 monocyte-derived macrophages above 80% at all periods. The 1:0.2:10 ratio of Cur-Bio PLGA NPs at a concentration of 250 μg/mL illustrated an enhanced reduction in the relative cholesterol content in the THP-1-derived foam cells compared to the 1:1:10 ratio. Confocal microscopy analysis also revealed a reduction in macrophage-mediated foam cell formation when administered with both the ratios of Cur-Bio PLGA NPs. Relative fold change in the mRNA expression of the genes involved in the inflammatory pathways in the atherosclerotic process downregulated NF-κB, CCL2/MCP-1, CD-36, and STAT-3 activity while upregulating the SCAR-B1 expression when treated with the Cur-Bio PLGA NPs. This study thus highlights the importance of natural-based compounds towards the therapeutic intervention against atherosclerotic activity when administered as preventive medicine.

Vigilance on New-Onset Atherosclerosis Following SARS-CoV-2 Infection

The pandemic of coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, has become a global challenge to public health. While its typical clinical manifestations are respiratory disorders, emerging evidence of cardiovascular complications indicates the adverse interaction between SARS-CoV-2 infection and cardiovascular outcomes. Given that viral infection has emerged as an additional risk factor for atherosclerosis, in this paper, we attempt to clarify the susceptibility to new-onset atherosclerosis in individuals infected with SARS-CoV-2. Mechanistically, serving as functional receptors for SARS-CoV-2, angiotensin-converting enzyme 2 (ACE2) mediates SARS-CoV-2 infection of endothelial cells (ECs) directly, leading to endothelial dysfunction and dysregulation of the renin-angiotensin system (RAS). In addition, high expression of CD147, an alternative receptor, and activation of the NLRP3 inflammasome may also contribute to atherosclerosis in the context of COVID-19. More importantly, SARS-CoV-2 attacks the immune system, which results in excessive inflammation and perpetuates a vicious cycle of deteriorated endothelial dysfunction that further promotes inflammation. The alterations in the blood lipid profile induced by COVID-19 should not be ignored in assessing the predisposition toward atherosclerosis in victims of COVID-19. A better understanding of the underlying mechanisms of SARS-CoV-2 infection and the long-term monitoring of inflammatory factors and endothelial function should be considered in the follow-up of patients who have recovered from COVID-19 for early detection and prevention of atherosclerosis.

Sarpogrelate and rosuvastatin synergistically ameliorate aortic damage induced by hyperlipidemia in apolipoprotein E-deficient mice

The current study aimed to investigate whether sarpogrelate and rosuvastatin possess anti-arterial injury, and attempted to elucidate the mechanism of action underlying this activity. Sarpogrelate, a 5-hydroxytryptamine type 2A antagonist, is extensively used to prevent arterial thrombosis; however, its effects on atherosclerosis remain unknown. In the present study, sarpogrelate combined with rosuvastatin or rosuvastatin alone were administered to male ApoE^-/- mice fed a high-fat diet (HFD) for 8 weeks. Metabolic parameters in the blood samples were analyzed using an automatic analyzer. Aortic tissues were stained with hematoxylin and eosin for morphological analysis. The expression levels of oxidized-low density lipoprotein (LDL) specific scavenging receptors, lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and cluster of differentiation 68 were detected via immunostaining. mRNA expression levels of interleukin (IL)-1β, IL-6 and tumor necrosis factor-α were determined via reverse transcription-quantitative PCR analysis, while protein expression levels of LOX-1 and phosphor(p)-ERK were determined via western blot analysis. The results demonstrated that sarpogrelate combined with rosuvastatin treatment significantly decreased total cholesterol and LDL cholesterol levels in the serum, and alleviated intimal hyperplasia and lipid deposition, accompanied by decreased inflammatory cell infiltration and lower expression levels of inflammatory cytokines, compared with rosuvastatin monotherapy or HFD treatment. Furthermore, sarpogrelate combined with rosuvastatin treatment significantly decreased the expression levels of LOX-1 and p-ERK. Taken together, these results suggest that the positive effects of sarpogrelate combined with rosuvastatin treatment on aortic injury may be associated with the regulation of the LOX-1/p-ERK signaling pathway. Sarpogrelate and rosuvastatin synergistically decreased aortic damage in ApoE^-/- HFD mice, and thus provide a basis for the treatment of aortic injury caused by hyperlipidemia with sarpogrelate.

Skate cartilage extracts containing chondroitin sulfate ameliorates hyperlipidemia-induced inflammation and oxidative stress in high cholesterol diet-fed LDL receptor knockout mice in comparison with shark chondroitin sulfate

BACKGROUND/OBJECTIVES

In this study, we investigated the beneficial effects of skate cartilage extracts containing chondroitin sulfate (SCS) on hyperlipidemia-induced inflammation and oxidative stress in high cholesterol diet (HCD)-fed mice in comparison with the effects of shark cartilage-derived chondroitin sulfate (CS).

MATERIALS/METHODS

Low-density lipoprotein receptor knockout (LDLR-KO) mice were fed HCD with an oral administration of CS (50 and 100 mg/kg BW/day), SCS (100 and 200 mg/kg BW/day), or water, respectively, for ten weeks.

RESULTS

The administration of CS or SCS reduced the levels of serum triglyceride (TG), total cholesterol (TC), and LDL cholesterol and elevated the levels of high-density lipoprotein cholesterol, compared with those of the control group (P < 0.05). Furthermore, CS or SCS significantly attenuated inflammation by reducing the serum levels of interleukin (IL)-1β and hepatic protein expression levels of nuclear factor kappa B, inducible nitric oxide synthase, cyclooxygenase-2, and IL-1beta (P < 0.05). In particular, the serum level of tumor necrosis factor-alpha was reduced only in the 100 mg/kg BW/day of SCS-fed group, whereas the IL-6 level was reduced in the 100 and 200 mg/kg BW/day of SCS-fed groups (P < 0.05). In addition, lipid peroxidation and nitric oxide production were attenuated in the livers of the CS and SCS groups mediated by the upregulation of hepatic proteins of antioxidant enzymes, such as superoxide dismutase, catalase, and glutathione peroxidase (P < 0.05).

CONCLUSIONS

These results suggest that the biological effects of SCS, similar to those of CS, are attributed to improved lipid profiles as well as suppressed inflammation and oxidative stress induced by the intake of HCD.

Response of vascular mesenchymal stem/progenitor cells to hyperlipidemia

Hyperlipidemia is a risk factor for atherosclerosis that is characterized by lipid accumulation, inflammatory cell infiltration, and smooth muscle cell proliferation. It is well known that hyperlipidemia is a stimulator for endothelial dysfunction and smooth muscle cell migration during vascular disease development. Recently, it was found that vessel wall contains a variable number of mesenchymal stem cells (MSCs) that are quiescent in physiological conditions, but can be activated by a variety of stimuli, e.g., increased lipid level or hyperlipidemia. Vascular MSCs displayed characteristics of stem cells which can differentiate into several types of cells, e.g., smooth muscle cells, adipocytic, chondrocytic, and osteocytic lineages. In vitro, lipid loading can induce MSC migration and chemokines secretion. After MSC migration into the intima, they play an essential role in inflammatory response and cell accumulation during the initiation and progression of atherosclerosis. In addition, MSC transplantation has been explored as a therapeutic approach to treat atherosclerosis in animal models. In this review, we aim to summarize current progress in characterizing the identity of vascular MSCs and to discuss the mechanisms involved in the response of vascular stem/progenitor cells to lipid loading, as well as to explore therapeutic strategies for vascular diseases and shed new light on regenerative medicine.

Gal-geun-dang-gwi-tang improves diabetic vascular complication in apolipoprotein E KO mice fed a western diet

BACKGROUND

Gal-geun-dang-gwi-tang (GGDGT), an herbal medicine, is used to treat hypertension, stroke, and other inflammatory disorders in the clinical setting. Recently, GGDGT was recognized by the Korea Institute of Oriental Medicine. This study aimed to evaluate the effects of GGDGT in a diabetic atherosclerosis model using apolipoprotein E knockout (ApoE-/-) mice fed a Western diet.

METHODS

The mice were divided into four groups: control group, C57BL6J mice receiving a regular diet (RD); ApoE-/- group, ApoE-/- mice receiving a Western diet (WD); rosiglitazone group, ApoE-/- mice receiving rosiglitazone (WD + 10 mg · kg(-1) · day(-1)); GGDGT group, ApoE-/- mice receiving GGDGT (WD + 200 mg · kg(-1) · day(-1)).

RESULTS

Treatment with GGDGT significantly improved glucose tolerance and plasma lipid levels. In addition, GGDGT ameliorated acetylcholine-induced vascular relaxation of the aortic rings. Immunohistochemical staining showed that GGDGT suppressed intercellular adhesion molecule (ICAM)-1 expression; however, expression of endothelial nitric oxide synthase (eNOS) and insulin receptor substrate (IRS)-1 were restored in the thoracic aorta and skeletal muscle, respectively.

CONCLUSIONS

These findings suggest that GGDGT attenuates endothelial dysfunction via improvement of the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) signalling pathway and improves insulin sensitivity in diabetic atherosclerosis.

Anti-Diabetic Atherosclerosis Effect of Prunella vulgaris in db/db Mice with Type 2 Diabetes

Diabetes mellitus is the leading cause of vascular complications such as atherosclerosis. This study was designed to investigate whether Prunella vulgaris (APV) would inhibit diabetic atherosclerosis in db/db mice with type 2 diabetes. The db/db mice were treated with high fat/high cholesterol (HFHC) diet and an aqueous extract of APV (100 and 200 mg/kg/day) for eight weeks to examine the long-term effect on metabolic abnormalities and diabetic atherosclerosis. APV treatment markedly lowered blood glucose and systolic blood pressure. The db/db mice experienced an increase in blood urea nitrogen as well as a decrease of creatinine clearance, the latter of which was restored by treatment with APV. Treatment with APV markedly decreased total plasma cholesterol, triglyceride, and LDL-cholesterol and also increased the HDL-cholesterol. In addition, malondialdehyde and TGF-β1 were decreased by treatment of APV. On the other hand, total NO level was decreased in db/db mice. However, the NO level was increased by treatment with APV, suggesting an association with vascular dysfunction. Vascular relaxation of aortic rings by acetylcholine or SNP-inducement was ameliorated by APV in a dose-dependent manner. Damage of vascular intima and hypertrophic of media were observed in db/db mice; however its dysfunction was improved by the treatment of APV. APV treatment significantly reduced the aortic expressions of ICAM-1, VCAM-1, ET-1, and nitrotyrosine. Furthermore, expression of eNOS in aortic was remarkably increased by APV treatment. Taken together, APV suppressed hyperglycemia and diabetic vascular dysfunction in HFHC diet-db/db mice. The present data suggest that Prunella vulgaris may prevent development of diabetic atherosclerosis.

Cynanchum wilfordii ameliorates hypertension and endothelial dysfunction in rats fed with high fat/cholesterol diets

Hypercholesterolemia increases the incidence of atherosclerosis and its pathologic complications. This study was performed to test the effect of an ethanol extract of Cynanchum wilfordii (ECW) on vascular dysfunction in rats fed with high fat/cholesterol diets (HFCD). Male rats were fed a HFCD consisting of 7.5% cocoa butter and 1.25% cholesterol, with or without 100, 200 mg/day/kg ECW. Rats fed with HFCD increased body weight associated with an increase in plasma low-density lipoprotein (LDL) cholesterol level. Chronic ECW treatment in HFCD-fed rats lessened LDL cholesterol and triglyceride levels as well as elevated high-density lipoprotein (HDL) cholesterol. Chronic ECW treatment recovered the HFCD-induced increase in systolic blood pressure, maintained smooth and soft intima endothelial layers by the decrease of intima-media thickness. ECW significantly recovered the diet-induced decrease in vasorelaxation to acetylcholine, high-dose ECW apparently increased vasorelaxation response to sodium nitroprusside in rats fed with HFCD. ECW clearly restored the HFCD-induced reduction in endothelial nitric oxide (NO) synthase expression and Akt expression levels in aortic tissue, leading to improve endothelial function through an increase in endothelium-derived NO production. Furthermore, treatment of ECW significantly recovered the HFCD-induced decrease in aortic cGMP levels in rats. These findings suggest that ECW ameliorates hypertension and endothelial dysfunction via improvement of NO/cGMP signaling pathway in aortic tissue of rats fed with HFCD, suggesting a vascular protective role for this herb in the treatment and prevention of atherosclerotic vascular disease.

Hypotensive, Hypolipidemic, and Vascular Protective Effects of Morus alba L. in Rats Fed an Atherogenic Diet

Morus alba L. has been used in traditional Chinese medicine and almost all parts of this plant are useful in cardiovascular, liver and spleen disorders. The present study was designed to investigate the inhibitory effect of a water extract from Morus alba L. (WMA) on vascular dysfunction in rat models fed a high fat and high cholesterol diet. Male rats were fed an atherogenic diet consisting of food with 7.5% cocoa butter and 1.25% cholesterol, with or without 100 or 200 mg/day/kg WMA, for 14 weeks. Chronic treatment with low (100 mg/kg/day) or high (200 mg/day/kg) doses of WMA markedly attenuated hypertension and the impairments of acetylcholine-induced relaxation of aortic rings in rats fed an atherogenic diet. WMA reduced intima/media thickness in rats fed an atherogenic diet. WMA improved plasma levels of triglyceride (TG) and augmented plasma levels of high-density lipoprotein (HDL) and plasma low-density lipoprotein (LDL), but did not affect blood glucose levels. Interestingly, WMA suppressed increased cell adhesion molecules such as E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intracellular adhesion molecule-1 (ICAM-1) expression in the aorta. Taken together, these results suggested that Morus alba L. could improve an atherogenic diet-induced hypertension, hyperlipidemia, and vascular dysfunction through inhibition of cell adhesion molecules expression and induction of vascular relaxation.

Effects of mulberry (Morus alba L.) extracts on lipid homeostasis in vitro and in vivo

The objective of this study was to investigate the lipid-lowering effects of mulberry water extracts (MWEs). To evaluate the hypolipidemic effect of MWEs, hamsters were fed with either high fat/cholesterol diets (HFCD) or HFCD supplemented with 1 and 2% MWEs for 12 weeks. Plasma total cholesterol (TC) and triglyceride (TG) levels of hamsters fed HFCD with MWEs were significantly reduced by about 30-37% and 16-35%, respectively, as compared to those without MWEs. Similar results were also measured in hepatic TC and TG of hamsters fed HFCD with MWEs. Low-density lipoprotein receptor (LDLR) gene expression and the uptake ability of low-density lipoprotein (LDL) in HepG2 cells were also upregulated by additions of MWEs. MWEs also decreased the gene expressions of enzymes involved in the TG and TC biosyntheses. Results suggest that hypolipidemic effects of MWEs are via an enhancement of LDLR gene expression and the clearance ability of LDL and a decrease in the lipid biosynthesis. Therefore, MWEs could be used as a natural agent against hyperlipidemia.