Advanced glycation end products (AGEs) are substances composed of amino groups of proteins and reducing sugars. The initial and propagation phases of the glycation process are accompanied by the production of a large amount of free radicals, carbonyl species, and reactive dicarbonyl species, of which, methylglyoxal (MG) is the most reactive and can cause dicarbonyl stress, influencing normal physiological functions. In the advanced phase, the production of AGEs and the interaction between AGEs and their receptor, RAGE, are also considered to be among the causes of chronic diseases, oxidative stress, and inflammatory reaction. Till date, multiple physiological activities of polyphenols have been confirmed. Recently, there have been many studies discussing the ability of polyphenols to suppress the MG and AGEs formation, which was also confirmed in some in vivo studies. This review article collects recent literatures concerning the effects of polyphenols on the generation of MG and AGEs through different pathways and discusses the feasibility of the inhibition of glycative stress and dicarbonyl stress by polyphenols.

The lysyl oxidase (LOX) family of oxidases contains a group of extracellular copper-dependent enzymes that catalyze the cross-linking of collagen and elastin by oxidation, thus maintaining the rigidity and structural stability of the extracellular matrix (ECM). Aberrant expression or activation of LOX alters the cellular microenvironment, leading to many diseases, including atherosclerosis, tissue fibrosis, and cancer. Recently, a number of studies have shown that LOX is overexpressed in most cancers and that it is involved in the regulation of tumor progression and metastasis. In contrast, a few reports have also indicated the tumor-suppressing role of LOX. In this short review, we discuss recent research on the correlations between LOX and cancer. Further, the role of LOX in tumor microenvironment remodeling, tumorigenesis, and metastasis and the underlying mechanisms have also been elucidated.

Isoliquiritigenin (2′,4′,4-trihydroxychalcone, ISL), one of the most important bioactive compounds with a chalcone structure, is derived from licorice root. Licorice is commonly known as Glycyrrhiza, including Glycyrrhiza uralensis, Glycyrrhiza radix, and Glycyrrhiza glabra, which are generally available in common foods and Chinese herbal medicines based on a wide variety of biological functions and pharmacological effects, and its derivative (ISL) is utilized as a food additive and adjunct disease treatment. In this review, we summarized the progress over the last 10 years in the targeted pathways and molecular mechanisms of ISL that are involved in the regulation of the onset and progression of different types of cancers.

Non-alcoholic fatty liver disease (NAFLD), the most common chronic liver disease, is closely associated with metabolic syndrome and refers to the accumulation of hepatic steatosis not due to excess alcohol consumption. Phyllanthus emblica L. is a rich source of gallic acid and many known medicinally phytochemicals such as tannins, lignans, flavonoids, alkaloids, vitamin C, mucic acid, and ellagic acid. Our previous study has revealed that P. emblica exhibits inhibitory effects on hepatic steatosis and liver fibrosis in vitro, as well as gallic acid improves high fat diet (HFD)-induced dyslipidaemia, hepatosteatosis, and oxidative stress in vivo. Therefore, the aim of this study was to investigate the hepatoprotective effect of the water extract of P. emblica L. fruit (WEPE) on NAFLD in an animal model. The results showed that WEPE could significantly decrease body weight, peritoneal fat and epididymal fat, enhance the antioxidant enzyme activities, and improve steatosis through elevating adiponectin in adipocytes and PPAR-α in the liver as well as lowering SREBP-1c in the liver of rats fed with a high fat diet (HFD). This might be an explanation for the hepatic fat deposition-lowering effect of WEPE. These results demonstrate that WEPE could be beneficial for the amelioration of HFD-induced steatosis.

(2013). Inhibitory effects of isoliquiritigenin on the migration and invasion of human breast cancer cells. Expert Opinion on Therapeutic Targets: Vol. 17, No. 4, pp. 337-349.

Age‐related macular degeneration (AMD) affects the retinal macula and results in loss of vision, and AMD is the primary cause of blindness and severe visual impairment among elderly people worldwide. AMD is characterized by the accumulation of drusen in the Bruch’s membrane and dysfunction of retinal pigment epithelial (RPE) cells and photoreceptors. The pathogenesis of AMD remains unclear, and no effective treatment exists. Accumulating evidence indicates that oxidative stress plays a critical role in RPE cell degeneration and AMD. Melatonin is an antioxidant that scavenges free radicals, and it has anti‐inflammatory, antitumor, and antiangiogenic effects. This study investigated the antioxidative, antiapoptotic, and autophagic effects of melatonin on oxidative damage to RPE cells. We used hydrogen peroxide (H₂O₂) to stimulate reactive oxygen species production to cause cell apoptosis in ARPE‐19 cell lines. Our findings revealed that treatment with melatonin significantly inhibited H₂O₂‐induced RPE cell damage, decreased the apoptotic rate, increased the mitochondrial membrane potential, and increased the autophagy effect. Furthermore, melatonin reduced the Bax/Bcl‐2 ratio and the expression levels of the apoptosis‐associated proteins cytochrome c and caspase 7. Additionally, melatonin upregulated the expression of the autophagy‐related proteins LC3‐II and Beclin‐1 and downregulated the expression of p62. Thus, melatonin’s effects on autophagy and apoptosis can protect against H₂O₂‐induced oxidative damage in human RPE cells. Melatonin may have multiple protective effects on human RPE cells against H₂O₂‐induced oxidative damage.