Advanced Glycation End Products and Health: A Systematic Review

The Association Between Two Different Non-invasive Advanced Glycation End Products and Osteoporosis in the Non-diabetic Population: A Cross-Sectional Study

Advanced glycation end products (AGEs) are associated with osteoporosis (OP) in the diabetic population. However, their relationship with OP in the non-diabetic population remains unclear. This study aimed to investigate cross-sectional associations of AGEs levels in the skin and lens with OP in the non-diabetic population. A retrospective analysis of clinical data of 652 participants was conducted. Bone mineral density (BMD) was quantified by dual-energy X-ray absorptiometry. Lens and skin AGEs were assessed by lens and skin autofluorescence (LAF and SAF). This study included 652 individuals, 280 males (42.9%) and 372 females (57.1%), with a mean age of (55.5 ± 6.9) years. The population with osteopenia exhibited significantly higher levels of SAF-AGEs than those with normal BMD, while the population with OP had significantly higher levels of both SAF- and LAF-AGEs. After adjusting for age and body mass index, LAF-AGEs were negatively correlated with BMD at the femoral neck and total hip. In contrast, SAF-AGEs were negatively correlated with BMD at the lumbar1-4 spine. Furthermore, multiple linear stepwise regression analysis demonstrated that LAF-AGEs were negatively associated with BMD at both the femoral neck and total hip. However, SAF-AGEs showed no association with BMD at any of the three measured sites. Additionally, after adjusting for other covariates, the logistic regression analysis emphasized that LAF-AGEs were associated with OP in the non-diabetic population, but SAF-AGEs do not. The results revealed a significant correlation between LAF-AGEs and OP in the non-diabetic population and their potential clinical utility warrants further validation. Therefore, we urge for larger longitudinal analyses and experimental research to validate and extend these cross-sectional findings.

Baicalein based nano-delivery system restores mitochondrial homeostasis through PPAR signaling pathway to promote wound healing in diabetes

Wound healing in diabetes is a substantial clinical challenge due to the hyperglycemic microenvironment, high pH, bacterial infection, persistent inflammation, and impaired cellular functions, attributed to mitochondrial dysfunction. Here, we have developed an injectable photo-crosslinking nanocomposite hydrogel (BA/GOx@ZIF-8@GelMA, BGZ@GelMA) with baicalein (BA) and glucose oxidase (GOx) loaded Zinc metal-organic framework (ZIF-8) based on methacrylated gelatin (GelMA) to accelerate diabetic infected wound healing by regulating subcellular and cellular functions. The combination of ZIF-8 and BA gives the hydrogel excellent antibacterial properties. A high blood sugar environment triggers the release of GOx in BGZ@GelMA, reducing local glucose and pH, producing hydrogen peroxide (H2O2), and releasing BA and Zinc ions (Zn2+). This process provides a suitable microenvironment for wound healing. Zn2+ can significantly inhibit the proliferation of Staphylococcus aureus (S.aureus) and Escherichia coli (E.coli). The released BA can clear ROS in cells and mitochondria, restore mitochondrial function and stability, and make the hydrogel fundamentally improve the cell function damage induced by hyperglycemia, and ultimately promote cell proliferation, migration and angiogenesis. In general, our multifunctional nanocomposite hydrogel provides a new strategy for diabetes wound healing at the subcellular and cellular functional levels.

Accelerated Biological Aging in Exfoliation Glaucoma Assessed by Fundus-Derived Predicted Age and Advanced Glycation End Products

Glaucoma is an age-related neurodegenerative disease characterized by progressive optic nerve damage. Accelerated biological aging, assessed using predicted age derived from fundus images, may serve as a biomarker for glaucoma progression. This study aimed to examine fundus-derived age acceleration among patients with primary open-angle glaucoma (POAG), exfoliation glaucoma (EXG), and controls, and to explore its biochemical basis through advanced glycation end products (AGEs). Fundus photographs from 237 participants (79 POAG, 79 EXG, and 79 age- and sex-matched controls) were analyzed using a deep learning model (EfficientNet) previously trained to predict biological age. AGE accumulation was assessed by measuring skin autofluorescence (sAF). Multivariate regression analyses were conducted to identify factors influencing predicted age acceleration, with stratification into age tertiles to control for age-related effects. EXG patients demonstrated significant accelerated biological aging compared to controls (p = 0.006), particularly evident in younger and middle-aged tertiles. AGE scores were significantly elevated in EXG relative to both POAG (p = 0.009) and control groups (p = 0.003). Predicted age and AGE scores were more strongly correlated than chronological age and AGEs, especially in the middle tertile (p = 0.002). Accelerated biological aging detected via fundus images occurs prominently in EXG, potentially reflecting underlying AGE accumulation. Fundus-derived predicted age could serve as a non-invasive biomarker for assessing glaucoma progression risk and warrants further exploration in clinical applications.

Cardamonin Attenuates Myocardial Ischemia/Reperfusion-Induced Ferroptosis Through Promoting STAT3 Signaling

Objective

Ferroptosis is intricately associated with the pathophysiology processes of myocardial ischemia. Cardamonin (CAR) has been shown to provide significant protection against tissue damage due to multiple ischemia/reperfusion. This study aimed to examine the cardioprotective properties of CAR in myocardial ischemia/reperfusion injury (MIRI) and provide insights into the possible mechanisms involved.

Methods

An MIRI mice model was conducted by coronary artery ligation, and the effects of CAR on myocardial tissue damage were evaluated by infarct size assessment, echocardiography, and H&E staining. The extent of ferroptosis was detected by examining the levels of ferroptosis-related proteins and lipid reactive oxygen species (ROS). The function pathway of CAR was analyzed by network pharmacology and verified using Western blotting. In addition, we induced hypoxia/reoxygenation (H/R) in cardiomyocytes to detect SLC7A11 expression, ROS level, mitochondrial iron content, and oxidative stress marker levels. The target protein of CAR was identified by Western blotting and molecular docking. We then evaluated the regulatory role of STAT3 on MIRI-induced ferroptosis by silencing STAT3.

Results

In our study, CAR demonstrated a reduction in myocardial histopathological damage and mitigation of ferroptosis in MIRI mice. Through network pharmacology analysis and Western blotting, our findings indicated that CAR modulates the AGE-RAGE signaling pathway, particularly impacting STAT3. Meanwhile, in vitro experiments revealed that advanced-glycation end products (AGEs) exacerbated H/R-induced ferroptosis, whereas CAR alleviated this ferroptosis in the presence of both AGEs and H/R. CAR was observed to enhance STAT3 expression in H/R+AGRs-treated cardiomyocytes. Molecular docking results demonstrated favorable binding interactions between CAR and STAT3. Our study confirmed that CAR mitigated MIRI-induced myocardial injury and ferroptosis through targeting STAT3 in mice.

Conclusion

In conclusion, CAR inhibited ferroptosis by activating the STAT3 signaling, thereby mitigating MIRI.

Phytochemical Composition and Functional Properties of Brassicaceae Microgreens: Impact of In Vitro Digestion

The aim of this study was to compare the concentration of phenolic compounds, glucosinolates, proteins, sugars and vitamin C between kohlrabi (Brassica oleracea var. acephala gongylodes), Savoy cabbage (B. oleracea sabauda), Brussels sprouts (B. oleracea gemmifera), cauliflower (B. oleracea botrytis), radish (Raphanus sativus) and garden cress (Lepidium sativum) microgreens for their antioxidant and hypoglycemic potential. In addition, we applied an in vitro-simulated system of human digestion in order to track the bioaccessibility of the selected phenolic representatives, and the stability of the microgreens' antioxidant and hypoglycemic potential in terms of α-amylase and α-glucosidase inhibition after each digestion phase. Using spectrophotometric and RP-HPLC methods with statistical analyses, we found that garden cress had the lowest soluble sugar content, while Savoy cabbage and Brussels sprouts had the highest glucosinolate levels (76.21 ± 4.17 mg SinE/g dm and 77.73 ± 3.33 mg SinE/g dm, respectively). Brussels sprouts were the most effective at inhibiting protein glycation (37.98 ± 2.30% inhibition). A very high positive correlation (r = 0.830) between antiglycation potential and conjugated sinapic acid was recorded. For the first time, the antidiabetic potential of microgreens after in vitro digestion was studied. Kohlrabi microgreens best inhibited α-amylase in both initial and intestinal digestion (60.51 ± 3.65% inhibition and 62.96 ± 3.39% inhibition, respectively), and also showed the strongest inhibition of α-glucosidase post-digestion (19.22 ± 0.08% inhibition). Brussels sprouts, cauliflower, and radish had less stable α-glucosidase than α-amylase inhibitors during digestion. Kohlrabi, Savoy cabbage, and garden cress retained inhibition of both enzymes after digestion. Kohlrabi antioxidant capacity remained unchanged after digestion. The greatest variability was seen in the original samples, while the intestinal phase resulted in the most convergence, indicating that digestion reduced differences between the samples. In conclusion, this study highlights the potential of various microgreens as sources of bioactive compounds with antidiabetic and antiglycation properties. Notably, kohlrabi microgreens demonstrated significant enzyme inhibition after digestion, suggesting their promise in managing carbohydrate metabolism and supporting metabolic health.

Nuclear Factor-Kappa-B Mediates the Advanced Glycation End Product-Induced Repression of Slc2a4 Gene Expression in 3T3-L1 Adipocytes

Advanced glycated end products (AGEs) are cytotoxic compounds that are mainly increased in diabetes mellitus (DM), kidney failure, inflammation, and in response to the ingestion of AGE-rich diets. AGEs can also impair glycemic homeostasis by decreasing the expression of the Slc2a4 (solute carrier family 2 member 4) gene and its GLUT4 (solute carrier family 2, facilitated glucose transporter member 4) protein in muscle. However, the mechanisms underlying AGE's effect on adipocytes have not been demonstrated yet. This study investigated the effects of AGEs upon Slc2a4/GLUT4 expression in 3T3-L1 adipocytes, as well as the potential role of NFKB (nuclear factor NF-kappa-B) activity in the effects observed. Adipocytes were cultured in the presence of control albumin (CA) or advanced glycated albumin (GA) at concentrations of 0.4, 3.6, and 5.4 mg/mL for 24 h or 72 h. Slc2a4, Rela, and Nfkb1mRNAs were measured by RT-qPCR, GLUT4, IKKA/B, and p50/p65 NFKB subunits using Western blotting, and p50/p65 binding into the Slc2a4 promoter was analyzed by chromatin immunoprecipitation (ChIP) assay. GA at 0.4 mg/mL increased Slc2a4/GLUT4 expression after 24 h and 72 h (from 50% to 100%), but at 5.4 mg/mL, Slc2a4/GLUT4 expression decreased at 72 h (by 50%). Rela and Nfkb1 expression increased after 24 h at all concentrations, but this effect was not observed at 72 h. Furthermore, 5.4 mg/mL of GA increased the p50/p65 nuclear content and binding into Slc2a4 at 72 h. In summary, this study reveals AGE-induced and NFKB-mediated repression of Slc2a4/GLUT4 expression. This can compromise the adipocyte glucose utilization, contributing not only to the worsening of glycemic control in DM subjects but also the impairment of glycemic homeostasis in non-DM subjects under the high intake of AGE-rich foods.

Cancerous Conditions Accelerate the Aging of Skeletal Muscle via Mitochondrial DNA Damage

Skeletal muscle aging and sarcopenia result in similar changes in the levels of aging markers. However, few studies have examined cancer sarcopenia from the perspective of aging. Therefore, this study investigated aging in cancer sarcopenia and explored its causes in vitro and in vivo. In mouse aging, in vitro cachexia, and mouse cachexia models, skeletal muscles showed similar changes in aging markers including oxidative stress, fibrosis, reduced muscle differentiation potential, and telomere shortening. Furthermore, examination of mitochondrial DNA from skeletal muscle revealed a 5 kb deletion in the major arc; truncation of complexes I, IV, and V in the electron transport chain; and reduced oxidative phosphorylation (OXPHOS). The mouse cachexia model demonstrated high levels of high-mobility group box-1 (HMGB1) and tumor necrosis factor-α (TNFα) in cancer ascites. Continuous administration of neutralizing antibodies against HMGB1 and TNFα in this model reduced oxidative stress and abrogated mitochondrial DNA deletion. These results suggest that in cancer sarcopenia, mitochondrial oxidative stress caused by inflammatory cytokines leads to mitochondrial DNA damage, which in turn leads to decreased OXPHOS and the promotion of aging.