Inhibition of leukocyte-type 12-lipoxygenase by guava tea leaves prevents development of atherosclerosis

Cocoa (Theobroma cacao L.) photobiological effect on human fibroblast cells (HFF-1) exposed to ultraviolet B (UVB) radiation

This study aimed to investigate the in vitro photobiological action of cocoa solution on a human fibroblast cell line (HFF-1) exposed to ultraviolet B (UVB) radiation. Three experimental models were utilized, where fibroblast cells were treated with different concentrations of cocoa as follows: 50; 100; 250; 500; 750; 1000 or 1500 µg/ml and concomitantly exposed to UVB 7 kJ/m2 for 10 min. The following parameters were examined 1) analysis of the pre-treatment action of cocoa; 2) investigation of the co-treatment activity of cocoa at the time of exposure; and 3) study the effect of cocoa in the post-treatment of the damage initiated by UVB. Cocoa exhibited biological action only in the post-treatment model at almost all tested concentrations compared to cells exposed to UVB alone. Further, fibroblast cells treated only with cocoa displayed higher levels of proliferation as evidenced by a decrease in the levels of basal reactive oxygen species (ROS) and nitric oxide (NO). In addition, cocoa also modulated the cell cycle of cells in the absence of UVB exposure by increasing the G2/M phase, although this did not generate significant changes in cells exposed concomitantly to cocoa and UVB. Therefore, data demonstrated that exposure to cocoa improved fibroblast cell-based control rates and exhibited an important reparative activity against damage initiated by UVB in human fibroblasts. Cocoa may thus be considered as a potential beneficial agent to be utilized in UVB-damaged skin cells.

Shexiang Tongxin dropping pill ameliorates microvascular obstruction via downregulating ALOX12 after myocardial ischemia-reperfusion

BACKGROUND

Microvascular dysfunction (MVD) is common in patients with myocardial infarction receiving reperfusion therapy and is associated with adverse cardiac prognosis. Accumulating evidence suggests a protective role of Shexiang Tongxin dropping pill (STDP) in MVD. However, the specific effects and the underlying mechanisms of STDP in the context of MVD after myocardial ischemia-reperfusion (IR) remains unclear.

AIMS

We aimed to elucidate the role of STDP in MVD induced by IR and the potential mechanisms involved.

METHODS

Mice were orally administered with STDP or normal saline for 5 days before receiving myocardial IR. Cardiac function and microvascular obstruction was measured. Proteomics and single-cell RNA sequencing was performed on mouse hearts. In vitro hyoxia/reoxygenation model was established on mouse cardiac microvascular endothelial cells (MCMECs).

RESULTS

STDP improved cardiac function and decreased microvascular obstruction (MVO) in mice after myocardial IR. Proteomics identified ALOX12 as an important target of STDP. Single-cell RNA sequencing further revealed that downregulation of ALOX12 by STDP mainly occurred in endothelial cells. The involvement of ALOX12 in the effect of STDP on MVO was validated by manipulating ALOX12 via endothelial-specific adeno-associated virus transfection in vivo and in vitro. In vivo, overexpression of ALOX12 increased whereas knockdown of ALOX12 decreased MVO and thrombus formation. STDP treatment alleviated the detrimental effects of overexpression of ALOX12. In vitro, overexpression of ALOX12 increased endothelial cell inflammation and platelet adhesion to endothelial cells, which was abolished by STDP treatment.

CONCLUSION

Our findings suggest that STDP alleviates MVO after IR, with ALOX12 playing a crucial role.

An Efficient Approach for Separating Essential Oil and Polysaccharides Simultaneously from Fresh Leaves of Guajava by Microwave-Mediated Hydrodistillation with Lithium Salts and Antibacterial Activity of Essential Oil

The essential oils and polysaccharides from guava leaves have important functions. In the process of microwave extraction of plant essential oils and polysaccharides, pretreatment with lithium salts solution is helpful to increase the extraction rate. The experiment was conducted using a single factor method. Results were optimized by principal component analysis and response surface optimization. The optimal conditions were: LiCl dosage 45 μmol, microwave time 40 min, liquid-solid ratio 10, homogenization time 4.2 min, liquid-material ratio 10, and microwave irradiation power 700 W. The highest yield of essential oil and polysaccharide were 10.27 ± 0.58 mL/kg dry weight (DW) and 50.31 ± 1.88 g/kg·DW, respectively. Three verification experiments showed that the extraction rate of the microwave method was higher than that of the traditional heating method. In addition, the bacteriostatic zones reached the maximum 23.7 ± 0.11 mm when the concentration was 40 μL/mL, and the above results have practical significance.

Roles of Nutraceuticals and Functional Food in Prevention of Cardiovascular Disease

The chapter provides an overview of cardiovascular disease, a major cause of mortality worldwide. It relates economic and social impacts to the disease, especially in developing countries. One of the approaches to addressing this challenge is increasing awareness within society, through implementation of education programs. It is important for society to understand the types and roles of the risk factors leading to cardiovascular disease. Emphasis is on the role of functional food and nutraceuticals as dietary sources that could prevent development of cardiovascular disease. The chapter highlights roles of nutraceuticals and functional food sources from medical plants, seeds, berries, and tropical fruits in lowering risk factors. Key findings from trials conducted in Asia, China, Europe, and America provide supporting evidence for the importance of functional food to health, and its potential for modifying the level of risk factors related to cardiovascular diseases.

The benzoate plant metabolite ethyl gallate prevents cellular- and vascular-lipid accumulation in experimental models of atherosclerosis

Ethyl gallate (EG) is a well-known constituent of medicinal plants, but its effects on atherosclerosis development are not clear. In the present study, the anti-atherosclerosis effects of EG and the underlying mechanisms were explored using macrophage cultures, zebrafish and apolipoprotein (apo) E deficient mice. Treatment of macrophages with EG (20 μM) enhanced cellular cholesterol efflux to HDL, and reduced net lipid accumulation in response to oxidized LDL. Secretion of monocyte chemotactic protein-1 (MCP-1) and interleukin-6 (IL-6) from activated macrophages was also blunted by EG. Fluorescence imaging techniques revealed EG feeding of zebrafish reduced vascular lipid accumulation and inflammatory responses in vivo. Similar results were obtained in apoE^-/- mice 6.5 months of age, where plaque lesions and monocyte infiltration into the artery wall were reduced by 70% and 42%, respectively, after just 6 weeks of injections with EG (20 mg/kg). HDL-cholesterol increased 2-fold, serum cholesterol efflux capacity increased by ∼30%, and the levels of MCP-1 and IL-6 were reduced with EG treatment of mice. These results suggest EG impedes early atherosclerosis development by reducing the lipid and macrophage-content of plaque. Underlying mechanisms appeared to involve HDL cholesterol efflux mechanisms and suppression of pro-inflammatory cytokine secretion.

12-Lipoxygenase promotes epithelial-mesenchymal transition via the Wnt/β-catenin signaling pathway in gastric cancer cells

Background

12-Lipoxygenase (12-LOX) plays a major role in the progression and metastasis of various types of cancer. In gastric cancer (GC), the expression level of 12-LOX is significantly up-regulated; however, its function, and underlying mechanism of action remain unclear.

Methods

The mRNA and protein expression levels of 12-LOX were assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analyses, respectively, in GC cell lines. 12-LOX expression was stably up-regulated using lentiviral vector in BGC823 and MGC803 cells, and cell-counting kit-8 (CCK8), colony formation, and invasion assays were performed to verify the function of 12-LOX in proliferation and metastasis. In addition, the expression levels of epithelial-mesenchymal transition (EMT) differentiation markers and downstream targets of the Wnt/β-catenin signaling pathway were examined by Western blotting. A nude mouse model of tumor growth and metastasis was established to investigate the role of 12-LOX in vivo.

Results

Our findings demonstrate that 12-LOX mRNA and protein were highly expressed in GC cell lines. 12-LOX overexpression promoted GC cell proliferation, migration, and invasion both in vitro and in vivo. In addition, up-regulation of 12-LOX promoted the EMT in GC cells, as reflected by a decrease in E-cadherin expression and an increase in N-cadherin and Snail expression. 12-LOX overexpression in GC cells also increased the expression of multiple downstream targets of the Wnt/β-catenin signaling pathway.

Conclusion

These findings revealed that 12-LOX functions as an oncogene in promoting GC cell proliferation and metastasis in vitro and in vivo. In addition, 12-LOX might regulate the EMT via the Wnt/β-catenin signaling pathway, indicating a potential role for 12-LOX as a target in GC treatment.

Roles of Nutraceuticals and Functional Food in Prevention of Cardiovascular Disease

The chapter provides an overview of cardiovascular disease, a major cause of mortality worldwide. It relates economic and social impacts to the disease, especially in developing countries. One of the approaches to addressing this challenge is increasing awareness within society, through implementation of education programs. It is important for society to understand the types and roles of the risk factors leading to cardiovascular disease. Emphasis is on the role of functional food and nutraceuticals as dietary sources that could prevent development of cardiovascular disease. The chapter highlights roles of nutraceuticals and functional food sources from medical plants, seeds, berries, and tropical fruits in lowering risk factors. Key findings from trials conducted in Asia, China, Europe, and America provide supporting evidence for the importance of functional food to health, and its potential for modifying the level of risk factors related to cardiovascular diseases.

Health Effects of Psidium guajava L. Leaves: An Overview of the Last Decade

Today, there is increasing interest in discovering new bioactive compounds derived from ethnomedicine. Preparations of guava (Psidium guajava L.) leaves have traditionally been used to manage several diseases. The pharmacological research in vitro as well as in vivo has been widely used to demonstrate the potential of the extracts from the leaves for the co-treatment of different ailments with high prevalence worldwide, upholding the traditional medicine in cases such as diabetes mellitus, cardiovascular diseases, cancer, and parasitic infections. Moreover, the biological activity has been attributed to the bioactive composition of the leaves, to some specific phytochemical subclasses, or even to individual compounds. Phenolic compounds in guava leaves have been credited with regulating blood-glucose levels. Thus, the aim of the present review was to compile results from in vitro and in vivo studies carried out with guava leaves over the last decade, relating the effects to their clinical applications in order to focus further research for finding individual bioactive compounds. Some food applications (guava tea and supplementary feed for aquaculture) and some clinical, in vitro, and in vivo outcomes are also included.