BACKGROUND: In populations with chronic disease, skin autofluorescence (SAF), a measure of long-term fluorescent advanced glycation end-products (AGEs) accumulation in body tissues, has been associated with vascular endothelial function, measured using flow-mediated dilation (FMD). The primary aim of this study was to quantify the relationship between endothelial function and tissue accumulation of AGEs in adults from the general population to determine whether SAF could be used as a marker to predict early impairment of the endothelium.
METHODS: A cross-sectional study was conducted with 125 participants (median age: 28.5 y, IQR: 24.4-36.0; 54% women). Endothelial function was measured by fasting FMD. Skin AGEs were measured as SAF using an AGE Reader. Participant anthropometry, blood pressure, and blood biomarkers were also measured. Associations were evaluated using multivariable regression analysis and were adjusted for significant covariates.
RESULTS: FMD was inversely correlated with SAF (ρ = -0.50, P < 0.001) and chronological age (ρ = -0.51, P < 0.001). In the multivariable analysis, SAF, chronological age, and male sex were independently associated with reduced FMD (B [95% CI]; -2.60 [-4.40, -0.80]; -0.10 [-0.16, -0.03]; 1.40 [0.14, 2.67], respectively), with the multivariable model adjusted R2 = 0.31, P < 0.001.
CONCLUSIONS: Higher skin AGE levels, as measured by SAF, were associated with lower FMD values, in a predominantly young, healthy population. Additionally, older age and male participants exhibited significantly lower FMD values, corresponding with compromised endothelial function. These results suggest that SAF, a simple and inexpensive marker, could be used to predict endothelial impairment before the emergence of any structural artery pathophysiology or classic cardiovascular disease risk markers.
BACKGROUND: The study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12621000821897) and concurrently entered into the WHO International Clinical Trials Registry Platform under the same ID number.

Advanced glycation end products (AGEs) are a diverse range of compounds that are formed when free amino groups of proteins, lipids, and nucleic acids are carbonylated by reactive carbonyl species or glycosylated by reducing sugars. Hyperglycemia in patients with diabetes can cause an overabundance of AGEs. Excess AGEs are generally acknowledged as major contributing factors to the development of diabetic complications because of their ability to break down the extracellular matrix directly and initiate intracellular signaling pathways by binding to the receptor for advanced glycation end products (RAGE). Inflammation and oxidative stress are the two most well-defined pathophysiological states induced by the AGE-RAGE interaction. In addition to oxidative stress, AGEs can also inhibit antioxidative systems and disturb iron homeostasis, all of which may induce ferroptosis. Ferroptosis is a newly identified contributor to diabetic complications. This review outlines the formation of AGEs in individuals with diabetes, explores the oxidative damage resulting from downstream reactions of the AGE-RAGE axis, and proposes a novel connection between AGEs and the ferroptosis pathway. This study introduces the concept of a vicious cycle involving AGEs, oxidative stress, and ferroptosis in the development of diabetic complications.

Methylglyoxal (MG) serves as the primary precursor for the nonenzymatic glycation of proteins and DNA, leading to advanced glycation end products (AGEs). Regular intake of dietary MG is strongly correlated with low-grade inflammation, potentially accelerating the pathogenesis of metabolic diseases, including obesity, diabetes, cancers, liver diseases, Alzheimer\'s disease, cardiovascular diseases, aging, and bone loss. Although pharmaceutical agents (pimagedine and candesartan) have been developed to inhibit MG formation, they often come with serious side effects (nausea, diarrhea, headache, gastrointestinal disturbance, symptomatic hypotension, abnormal renal and liver function tests, development of antinuclear antibody, pernicious-like anemia, and hyperkalemia), highlighting the need for an efficient and safe approach to scavenging MG. Phyllanthus emblica Linn fruit, a nutritious edible fruit, and medicinal plant contains over 300 bioactive compounds. Among twenty-three herbals, 100 μg/mL of the aqueous extract of Phyllanthus emblica fruit (APF) exhibits the highest potency in trapping MG, achieving an 87.3 % reduction under d-fructose induced BSA-AGEs formation. However, there are few reports detailing APF and its related foods\' specific impact on disease prevention through MG trapping. This review summarizes the mechanisms through which MG is linked to the development of metabolic diseases and provides several strategies for reducing MG levels using APF and its bioactive compounds. The potential antiglycation properties of APF may offer new applications in the food industry and pharmacological research.

The burden of diabetes is rising in developing countries, and this is significantly linked to the increasing prevalence of poor glycemic control. The cost of glycated haemoglobin (HbA1c) testing is a barrier to timely glycemic assessments, but newer tests such as glycated albumin may be cheaper and tempting alternatives. Additional research must ascertain if glycated albumin (GA) can act as a viable supplement or alternative to conventional HbA1c measurements for glycemic control in diabetic individuals. GA as a biomarker is an emerging area of interest, particularly for those who display unreliable HbA1c levels or cannot afford the test. This study aims to investigate the prevalence of poor glycemic control in outpatient diabetic patients and the utility of glycated albumin in this population\'s monitoring of glycemic control. Method. A cross-sectional study of 203 diabetic patients will be conducted at the Dodoma Regional Referral Hospital and Benjamin Mkapa Hospital from August 1st, 2023, to August 31st, 2024. Patients diagnosed with diabetes mellitus for over six months will be screened for eligibility. Informed consent, history, clinical examination, and voluntary blood sample collection will be obtained from all eligible patients. Glycated Albumin levels will be obtained from the same blood samples collected. The glycemic status of all patients will be defined as per HbA1c, and a level of greater than 7% will considered as a poor control. The analysis will be computed with SPSS version 28.0, and a predictor variable, P<0.05, will be regarded as statistically significant, with the utility of GA determined by plotting the area under the ROC curve and the confusion matrix.

BACKGROUND: The AGEs levels in tissues of diabetics and elderly tend to be higher than in normal individuals. This study aims to determine the effects of AGEs on Achilles tendon repair.
METHODS: Thirty-six male eight-week-old Sprague Dawley rats were selected in this study. The rats were randomly divided into two experimental groups and a control group after the transection of the Achilles tendon. During the tendon repair, the experimental groups were injected around the Achilles tendon with 350mmol/L (low dose group) and 1000mmol/L (high dose group) D-ribose 0.2 ml respectively to increase the AGEs level, while in the control group were given the same amount of PBS. The injections were given twice a week for six weeks. Collagen-I, TNF-α, and IL-6 expression in the healed Achilles tendon was assessed. Additionally, macroscopic, pathological, and biomechanical evaluations of Achilles tendon repair were conducted.
RESULTS: The repaired Achilles tendons in the high dose group showed severe swelling and distinctive adhesions. The histological score went up with the increase of the AGEs in the Achilles tendon (p<0.001). TNF- α and IL-6 in the Achilles tendon increased (p<0.001, p<0.001), and the production of collagen-I decreased with the accumulation of AGEs in the repaired Achilles tendon (p<0.001). The tensile strength of Achilles tendon in the high dose group was impaired significantly.
CONCLUSIONS: In current study, the compromised tendon repair model induced by AGEs was successfully established in rat. The study demonstrated that AGEs significantly impair Achilles tendon repair.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) shares common pathogenic mechanisms of type 2 diabetes mellitus (T2DM) with upregulated advanced glycation end products (AGEs). Here, we aim to investigate the effect of FPS-ZM1, an inhibitor for receptor for AGEs (RAGE), on lipid deposition in the liver of mice.
METHODS: KK-Ay mice were used as models of T2DM with NAFLD, while C57BL/6j mice were controls. Additionally, KK-Ay mice were treated with DMSO (with a concentration of 1%), with or without FPS-ZM1 (3 mg/kg/day, i.p). Lipid deposition in hepatocytes was observed using oil red O stain. Levels of AGEs and RAGE were measured. Sterol regulatory element-binding protein-1c (SREBP-1c), as well as nuclear factor κB p65 (p65 nfκb) and mitogen-activated protein kinase p38 (p38 MAPK), were also detected.
RESULTS: Lipid deposition is increased in the hepatocytes of KK-Ay mice compared to C57BL/6j mice. In addition, not only were the levels of AGEs elevated in plasma, but also the levels of RAGE in liver tissue. Although total SREBP-1c levels did not change in the liver of diabetic mice, mature SREBP-1c increased in KK-Ay mice with diabetes mellitus. Moreover, diabetic mice showed increased levels of phosphorylated-p65 nfκb (p-p65 nfκb) and phosphorylated-p38 MAPK (p-p38 MAPK). On the contrary, FPS-ZM1 decreased lipid deposition in liver cells, as well as mature SREBP-1c, p-p65 nfκb and p-p38 MAPK levels in liver tissue.
CONCLUSIONS: Generally, FPS-ZM1 may attenuate lipid deposition in hepatocytes of diabetic mice via SREBP-1c down-regulation. This may depend on the downregulation of p65 nfκb and p38 MAPK phosphorylation.

Glycation is an important nonenzymatic reaction between reducing sugars and amines. Advanced glycation end products (AGEs) accumulation in the human body is associated with secondary complications related to diabetes in hyperglycemic environments. These observations suggest that the inhibition of AGEs formation is important for preventing diabetes mellitus (DM) progression and the development of diabetes-related complications. Lactic acid bacteria (LAB) are probiotics commonly used in fermented foods and food additives. Therefore, it is necessary to identify starter strains of LAB to produce fermented food to decrease the risk of DM and its complications. This chapter introduces the protocols that are inhibition assay of fermented food using LAB on AGEs such as Nω-(carboxymethyl) arginine (CMA), Nε-(carboxymethyl) lysine (CML), and fluorescent AGEs.

UNASSIGNED: Ovarian granulosa cells (GCs) are essential for follicular development. Ovarian advanced glycation end-products (AGEs) accumulation is related to GCs dysfunction. Alpha-lipoic acid (ALA) illustrates therapeutic capabilities for infertility-related disorders. Therefore, this study assessed the effects of ALA on AGEs-induced GCs hormonal dysfunction.
UNASSIGNED: The study was conducted from October 2021 to September 2022 at the Department of Medical Genetics, Shiraz University of Medical Sciences. Isolated GCs (n=50) were divided into control, human glycated albumin (HGA), HGA+ALA, and ALA treatments. Steroidogenic enzymes and AGE receptor (RAGE) genes were assessed by qRT-PCR. Steroid hormones and RAGE protein were evaluated using ELISA and Western blotting. Data were analyzed using GraphPad Prism software (ver. 9), and P<0.05 was considered significant.
UNASSIGNED: Our findings showed that HGA treatment significantly (P=0.0001) increased RAGE (by 140.66%), STAR (by 117.65%), 3β-HSD (by 165.68%), and 17β-HSD (by 122.15%) expression, while it decreased CYP19A1 (by 68.37%) expression. RAGE protein level (by 267.10%) was also increased in HGA-treated GCs. A significant decrease in estradiol (by 59.66%) and a slight and sharp elevation in progesterone (by 30.40%) and total testosterone (by 158.24%) levels was also observed. ALA treatment ameliorated the HGA-induced changes in steroidogenic enzyme mRNA levels (P=0.001) and steroid hormone secretion (P=0.010).
UNASSIGNED: This work shows that ALA therapy likely corrects hormonal dysfunctions caused by AGEs in luteinized GCs. This effect is probably achieved by decreased RAGE expression. Clinical research is needed to understand how AGEs and ALA interact in the ovary, which might lead to a more targeted ovarian dysfunction therapy.

Exogenous and endogenous advanced glycation end products (AGEs) contribute to the pathogenesis and progression of renal disease. This is a one-month controlled dietary counseling trial that restricts nutritional AGEs in patients with end-stage renal disease (ESRD) undergoing haemodialysis (n = 22 participants in the intervention and n = 20 participants in the control group). Haematological, biochemical markers, the soluble form of the receptor for AGEs (sRAGE), and carboxymethyl lysine (CML) were measured at baseline and at follow-up. Mononuclear cells were isolated and the protein expression of RAGE and the inflammatory marker COX-2 was measured using Western immunoblotting. The intervention group presented a lower increase in CML compared to the control group (12.39% median change in the intervention vs. 69.34% in the control group, p = 0.013), while RAGE (% mean change -56.54 in the intervention vs. 46.51 in the control group, p < 0.001) and COX-2 (% mean change -37.76 in the intervention vs. 0.27 in the control group, p < 0.001) were reduced compared to the control group. sRAGE was reduced in both groups. In addition, HbA1c (at two months), total cholesterol, and triglycerides were reduced in the intervention versus the control group. The adoption of healthy cooking methods deserves further research as a possible way of modulating inflammatory markers in patients with CKD.

Advanced glycation end products (AGEs) are a spectrum of complex compounds widely found in processed foods and frequently consumed by humans. AGEs are implicated in impairing the intestinal barrier, but the underlying mechanisms remain unclear. This study investigated the effects of three types of AGEs on gene expression of tight junctions (TJs) in colorectal epithelial HT-29 cells, and observed minimal alterations in TJs expression. Given the important role of subepithelial macrophages in regulating the intestinal barrier, we explored whether AGEs affect the intestinal barrier via the involvement of macrophages. Notably, a significant downregulation of TJs expression was observed when supernatants from AGEs-treated RAW264.7 macrophage cells were transferred to HT-29 cells. Further investigations indicated that AGEs increased IL-6 levels in RAW264.7 cells, subsequently triggering STAT3 activation and suppressing TJs expression in HT-29 cells. The role of STAT3 activation was confirmed by observing enhanced TJs expression in HT-29 cells following pretreatment with an inhibitor of STAT3 activation prior to the transfer of the conditioned medium. These findings demonstrated that AGEs impaired the intestinal barrier via macrophage-mediated STAT3 activation, shedding light on the mechanisms underlying AGEs-induced intestinal barrier injury and related food safety risks.