Diabetes-induced hepatic oxidative stress: a new pathogenic role for glycated albumin

Mitigating methylglyoxal-induced glycation stress: the protective role of iron, copper, and manganese coordination compounds in Saccharomyces cerevisiae

Glycation-induced stress (G-iS) is a physiological phenomenon that leads to the formation of advanced glycation end-products, triggering detrimental effects such as oxidative stress, inflammation, and damage to intracellular structures, tissues, and organs. This process is particularly relevant because it has been associated with various human pathologies, including cancer, neurodegenerative diseases, and diabetes. As therapeutic alternatives, coordination compounds with antioxidant activity show promising potential due to their versatility in attenuating oxidative stress and inflammation. Herein, we investigated the antioxidant-related protective potential of a series of complexes: [Cu(II)(BMPA)Cl2] (1), [Fe(III)(BMPA)Cl3] (2), and [Cl(BMPA)MnII-(μ-Cl)2-MnII(BMPA)-(μ-Cl)- MnII(BMPA)(Cl)2]•5H2O (3), all synthesized with the ligand bis-(2-pyridylmethyl)amine (BMPA) in Saccharomyces cerevisiae exposed to G-iS caused by methylglyoxal (MG). Pre- treatment with complexes 1-3 proved highly effective, increasing yeast tolerance to G-iS and attenuating mitochondrial dysfunction. This observed phenotype appears to result from a reduction in intracellular oxidation, lipid peroxidation levels, and glycation. Additionally, an increase in the activity of the antioxidant enzymes superoxide dismutase and catalase was observed following treatment with complexes 1-3. Notably, although complexes 1-3 provided significant protection against oxidative stress induced by H2O2 and menadione, their protective role was more effective against MG-induced glycation stress. Our results indicate that these complexes possess both antiglycation and antioxidant properties, warranting further investigation as potential interventions for mitigating glycation and oxidative stress-related pathologies.

Coffee Bioactive N-Methylpyridinium: Unveiling Its Antilipogenic Effects by Targeting De Novo Lipogenesis in Human Hepatocytes

SCOPE

Type 2 diabetes and nonalcoholic fatty liver diseases (NAFLDs) are promoted by insulin resistance (IR), which alters lipid homeostasis in the liver. This study aims to investigate the effect of N-methylpyridinium (NMP), a bioactive alkaloid of coffee brew, on lipid metabolism in hepatocytes.

METHODS AND RESULTS

The effect of NMP in modulating lipid metabolism is evaluated at physiological concentrations in a diabetes cell model represented by HepG2 cells cultured in a high-glucose medium. Hyperglycemia triggers lipid droplet accumulation in cells and enhances the lipogenic gene expression, which is transactivated by sterol regulatory element binding protein-1 (SREBP-1). Lipid droplet accumulation alters the redox status and endoplasmic reticulum (ER) stress, leading to the activation of the unfolded protein response and antioxidative pathways by X-Box Binding Protein 1(XBP-1)/eukaryotic Initiation Factor 2 alpha (eIF2α) Protein Kinase RNA-Like ER Kinase and nuclear factor erythroid 2-related factor 2 (NRF2), respectively. NMP induces the phosphorylation of AMP-dependent protein kinase (AMPK) and acetyl-CoA carboxylase α (ACACA), and improves the redox status and ER homeostasis, essential steps to reduce lipogenesis and lipid droplet accumulation.

CONCLUSION

These results suggest that NMP may be beneficial for the management of T2D and NAFLD by ameliorating the cell oxidative and ER homeostasis and lipid metabolism.

Glycated LDL generates reactive species that damage cell components, oxidize hemoglobin and alter surface morphology in human erythrocytes

Low-density lipoprotein (LDL) transports cholesterol to various tissues via the blood. Glycation of LDL occurs during hyperglycemic condition which is characterised by persistently high blood glucose level. Circulating erythrocytes can come in direct contact with glycated LDL (G-LDL). The objective of this study was to investigate the effect of G-LDL on human erythrocytes, specifically on hemoglobin, intracellular generation of reactive species and the antioxidant defence system. Isolated erythrocytes were incubated with G-LDL (3 and 6 mg/ml) and native LDL (6 mg/ml) at 37 °C for 24 h. Native LDL and G-LDL untreated erythrocytes were similarly incubated at 37 °C and served as control. G-LDL treatment increased hemolysis compared to control and native LDL-treated erythrocytes. Incubation of erythrocytes with G-LDL led to an increase in protein oxidation and lipid peroxidation while greatly decreasing the total sulfhydryl content. It also significantly enhanced hemoglobin oxidation, heme degradation, and the release of free iron moiety. Treatment with G-LDL led to an appreciable increase in the production of reactive oxygen and nitrogen species. The antioxidant power and activities of major antioxidant enzymes were drastically reduced, while critical membrane-bound enzymes were inhibited. The surface morphology of G-LDL-treated erythrocytes was altered leading to the formation of echinocytes. Importantly, treatment of erythrocytes with native LDL did not significantly affect the above-mentioned parameters and values were similar to the corresponding controls. Thus, G-LDL is cytotoxic to human erythrocytes and causes oxidative damage to cell components. This can reduce the oxygen-transporting ability of blood and also result in red cell senescence and anemia.

Impaired brain equanimity and neurogenesis in the diet-induced overweight mouse: a preventive role by syringic acid treatment

OBJECTIVES

In this study mice were fed a high-fat diet for 12 weeks to establish diet-induced obesity and syringic acid (SA) was assessed for anti-obese, neuroprotective, and neurogenesis.

METHOD

Animals were given HFD for 12 weeks to measure metabolic characteristics and then put through the Barns-maze and T-maze tests to measure memory. Additionally, the physiology of the blood-brain barrier, oxidative stress parameters, the expression of inflammatory genes, neurogenesis, and histopathology was evaluated in the brain.

RESULT

DIO raised body weight, BMI, and other metabolic parameters after 12 weeks of overfeeding. A reduced spontaneous alternation in behavior (working memory, reference memory, and total time to complete a task), decreased enzymatic and non-enzymatic antioxidants, oxidative biomarkers, increased neurogenesis, and impaired blood-brain barrier were all seen in DIO mice. SA (50 mg/kg) treatment of DIO mice (4 weeks after 8 weeks of HFD feeding) reduced diet-induced changes in lipid parameters associated with obesity, hepatological parameters, memory, blood-brain barrier, oxidative stress, neuroinflammation, and neurogenesis. SA also reduced the impact of malondialdehyde and enhanced the effects of antioxidants such as glutathione, superoxide dismutase (SOD), and total thiol (MDA). Syringic acid improved neurogenesis, cognition, and the blood-brain barrier while reducing neurodegeneration in the hippocampal area.

DISCUSSION

According to the results of the study, syringic acid therapy prevented neurodegeneration, oxidative stress, DIO, and memory loss. Syringic acid administration may be a useful treatment for obesity, memory loss, and neurogenesis, but more research and clinical testing is needed.

Hypoglycemic activities of flowers of Xanthoceras sorbifolia and identification of anti-oxidant components by off-line UPLC-QTOF-MS/MS-free radical scavenging detection

Objective

To identify phytochemical constituents present in the extract of flowers of Xanthoceras sorbifolia and evaluate their anti-oxidant and anti-hyperglycemic capacities.

Methods

The AlCl3 colorimetric method and Prussian Blue assay were used to determine the contents of total flavonoids and total phenolic acids in extraction layers, and the bioactive layers was screened through anti - oxidative activity in vitro. The Waters ACQUITY UPLC system and a Waters ACQUITY UPLC BEH C18 column (2.0 mm × 150 mm, 5 μm) were used to identify the ingredients. And anti-oxidative ingredients were screened by off-line UPLC-QTOF-MS/MS-free radical scavenging. The ameliorative role of it was further evaluated in a high-fat, streptozotocin-induced type 2 diabetic rat model and the study was carried out on NADPH oxidase (PDB ID: 2CDU) by molecular docking.

Results

Combined with the results of activity screening in vitro, the anti - oxidative part was identified as the ethyl acetate layer. A total of 24 chemical constituents were identified by liquid chromatography-mass spectrometry in the ethyl acetate layer and 13 main anti-oxidative active constituents were preliminarily screened out through off-line UPLC-QTOF-MS/MS-free radical scavenging. In vivo experiments showed that flowers of X. sorbifolia could significantly reduce the blood glucose level of diabetic mice and alleviate liver cell damage. Based on the results of docking analysis related to the identified phytocompounds and oxidase which involved in type 2 diabetes, quercetin 3-O-rutinoside, kaempferol-3-O-rhamnoside, isorhamnetin-3-O-glucoside, and isoquercitrin showed a better inhibitory profile.

Conclusion

The ethyl acetate layer was rich in flavonoids and phenolic acids and had significant anti-oxidant activity, which could prevent hyperglycemia. This observed activity profile suggested X. sorbifolia flowers as a promising new source of tea to develop alternative natural anti-diabetic products with a high safety margin.

Conformational variation of site specific glycated albumin: A Molecular dynamics approach

Human serum albumin (HSA) is a major cargo protein, which undergoes glycation in hyperglycaemic conditions and results in impaired function. In physiological conditions, HSA plays a crucial role in pharmacological activities such as drug transport or delivery through its binding capacity and also by its enzymatic activity, which enables the translation of pro-drugs into active drugs. In this study, the impact of the methylglyoxal-mediated glycation on dynamic behaviour of inter-domain motion, Cys34 reactivity, binding site residual interaction and secondary structure transition were investigated through molecular dynamics simulation. The alteration in inter-domain motion reflects the effect of glycation-mediated changes on the structural conformation of albumin. The binding site residue interactions and volume analysis revealed the impact of glycation on the geometry of the binding site. We also found the correlation of Cys34 reactivity with increase of turns in the region between Ia-h4 and Ia-h5. The rise in turn formation in that region keeps Tyr84 farther away from Cys34 which could lead to higher Cys34 reactivity. In parallel, significant alterations in alpha helical content of helices in the binding sites were observed. These structural and conformational changes in glycated albumin could be the causative agents for functional impairment which leads to diabetic complications.

Transgenic type2 diabetes mouse models for in vivo redox measurement of hepatic mitochondrial oxidative stress

BACKGROUND

Oxidative stress is involved in the progression of diabetes and its associated complications. However, it is unclear whether increased oxidative stress plays a primary role in the onset of diabetes or is a secondary indicator caused by tissue damage. Previous methods of analyzing oxidative stress have involved measuring the changes in oxidative stress biomarkers. Our aim is to identify a novel approach to clarify whether oxidative stress plays a primary role in the onset of diabetes.

METHODS

We constructed transgenic type 2 diabetes mouse models expressing redox-sensitive green fluorescent proteins (roGFPs) that distinguished between mitochondria and whole cells. Pancreas, liver, skeletal muscle, and kidney redox states were measured in vivo.

RESULTS

Hepatic mitochondrial oxidation increased when the mice were 4 weeks old and continued to increase in an age-dependent manner. The increase in hepatic mitochondrial oxidation occurred simultaneously with weight gain and increased blood insulin levels before the blood glucose levels increased. Administering the oxidative stress inducer acetaminophen increased the vulnerability of the liver mitochondria to oxidative stress.

CONCLUSIONS

This study demonstrates that oxidative stress in liver mitochondria in mice begins at the onset of diabetes rather than after the disease has progressed.

GENERAL SIGNIFICANCE

RoGFP-expressing transgenic type 2 diabetes mouse models are effective and convenient tools for measuring hepatic mitochondrial redox statuses in vivo. These models may be used to assess mitochondria-targeting antioxidants and establish the role of oxidative stress in type 2 diabetes.

SENP6-Mediated deSUMOylation of VEGFR2 Enhances Its Cell Membrane Transport in Angiogenesis

Angiogenesis is a significant pathogenic characteristic of diabetic microangiopathy. Advanced glycation end products (AGEs) are considerably elevated in diabetic tissues and can affect vascular endothelial cell shape and function. Regulation of the vascular endothelial growth factor (VEGF)-VEGF receptor 2 (VEGFR2) signaling pathway is a critical mechanism in the regulation of angiogenesis, and VEGFR2 activity can be modified by post-translational changes. However, little research has been conducted on the control of small ubiquitin-related modifier (SUMO)-mediated VEGFR2 alterations. The current study investigated this using human umbilical vein endothelial cells (HUVECs) in conjunction with immunoblotting and immunofluorescence. AGEs increased Nrf2 translocation to the nucleus and promoted VEGFR2 expression. They also increased the expression of sentrin/SUMO-specific protease 6 (SENP6), which de-SUMOylated VEGFR2, and immunofluorescence indicated a reduction in VEGFR2 accumulation in the Golgi and increased VEGFR2 transport from the Golgi to the cell membrane surface via the coatomer protein complex subunit beta 2. VEGFR2 on the cell membrane was linked to VEGF generated by pericytes, triggering the VEGF signaling cascade. In conclusion, this study demonstrates that SENP6 regulates VEGFR2 trafficking from the Golgi to the endothelial cell surface. The SENP6-VEGFR2 pathway plays a critical role in pathological angiogenesis.

Effects of NAC assisted insulin on cholesterol metabolism disorders in canine type 1 diabetes mellitus

Type 1 diabetes mellitus (T1DM) is a metabolic disease characterized by insulin deficiency and often accompanied by hypercholesterolemia. NAC is an effective antioxidative drug, but its application in the treatment of diabetes is still rare. A total of forty beagles were randomly divided into five groups: control group, DM group, INS group, INS with NAC group, and NAC group. The experiment lasted for 120 days. Results revealed that biochemical criterion increased in the DM group, while the indicators significantly decreased on the INS combined with NAC treatment group. Moreover, the insulin released test demonstrated that the model of T1DM was successfully constructed. The result of B ultrasound of gallbladder showed remarkable cholestasis in DM group. The cholesterol metabolism-related enzyme activity (HMGCR and SQLE) was evidently increased in DM group, but decreased in INS and NAC group. The content of TG, LDL-c, and HDL-c in liver was detected by the kit, and it was found that the content of TG, LDL-c, and HDL-c in DM group were reduced. Histopathological observation revealed that the cholestasis of liver cells and hepatic cords were disordered in DM group, the symptoms were alleviated under INS and NAC treatment. Additionally, the protein and mRNA expression of HMGCR and LDLR were obviously increased in DM group, but down regulated in INS and NAC treatment group. Overall, the liver function injury and secondary hypercholesterolemia can be found in T1DM canines, and NAC can relieve cholesterol metabolism disorder in the treatment of canine T1DM.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2017-2018

This review is the tenth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization mass spectrometry (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2018. Also included are papers that describe methods appropriate to glycan and glycoprotein analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. Topics covered in the first part of the review include general aspects such as theory of the MALDI process, new methods, matrices, derivatization, MALDI imaging, fragmentation and the use of arrays. The second part of the review is devoted to applications to various structural types such as oligo- and poly-saccharides, glycoproteins, glycolipids, glycosides, and biopharmaceuticals. Most of the applications are presented in tabular form. The third part of the review covers medical and industrial applications of the technique, studies of enzyme reactions, and applications to chemical synthesis. The reported work shows increasing use of combined new techniques such as ion mobility and highlights the impact that MALDI imaging is having across a range of diciplines. MALDI is still an ideal technique for carbohydrate analysis and advancements in the technique and the range of applications continue steady progress.

Allicin Alleviates Diabetes Mellitus by Inhibiting the Formation of Advanced Glycation End Products

Advanced glycation end products (AGEs) cause damage to pancreatic β-cells and trigger oxidative stress and inflammation, which promotes the development and progression of diabetes and its complications. Therefore, it is important to inhibit the formation of AGEs as part of the treatment of diabetes. Allicin is a natural antimicrobial agent with abundant pharmacological activities, and recent studies have reported its therapeutic effects in diabetes; however, the mechanism of these therapeutic effects is still unclear. Thus, the purpose of this study was to further investigate the association between allicin treatment of diabetes and AGEs. First, we established a streptozocin (STZ)-induced diabetic rat model and treated the rats with allicin for six weeks. We measured glycolipid metabolism, AGE levels, receptor of advanced glycation end products (RAGE) levels, oxidative stress, and other related indicators. The results showed that allicin improved blood glucose and body weight, reduced lipid accumulation, and inhibited AGE formation in rats. Treatment with allicin also inhibited RAGEs and thereby prevented AGE activity, which, in turn, alleviated oxidative stress and promoted insulin secretion. To further verify the effect of allicin on AGEs, we also performed in vitro nonenzymatic glycation simulation experiments. These results showed that allicin inhibited the production of AGEs by suppressing the production of AGEs intermediates. Thus, our research suggests that allicin may alleviate diabetes by inhibiting the formation of AGEs and reducing RAGE levels to relieve oxidative stress and promote insulin secretion.

Nano-titanium dioxide inhalation exposure during gestation drives redox dysregulation and vascular dysfunction across generations

BACKGROUND

Pregnancy is associated with many rapid biological adaptations that support healthy development of the growing fetus. One of which is critical to fetal health and development is the coordination between maternal liver derived substrates and vascular delivery. This crucial adaptation can be potentially derailed by inhalation of toxicants. Engineered nanomaterials (ENM) are commonly used in household and industrial products as well as in medicinal applications. As such, the potential risk of exposure remains a concern, especially during pregnancy. We have previously reported that ENM inhalation leads to upregulation in the production of oxidative species. Therefore, we aimed to determine if F0 dam maternal nano-TiO₂ inhalation exposure (exclusively) resulted in altered H₂O₂ production capacity and changes in downstream redox pathways in the F0 dams and subsequent F1 pups. Additionally, we investigated whether this persisted into adulthood within the F1 generation and how this impacted F1 gestational outcomes and F2 fetal health and development. We hypothesized that maternal nano-TiO₂ inhalation exposure during gestation in the F0 dams would result in upregulated H₂O₂ production in the F0 dams as well as her F1 offspring. Additionally, this toxicological insult would result in gestational vascular dysfunction in the F1 dams yielding smaller F2 generation pups.

RESULTS

Our results indicate upregulation of hepatic H₂O₂ production capacity in F0 dams, F1 offspring at 8 weeks and F1 females at gestational day 20. H₂O₂ production capacity was accompanied by a twofold increase in phosphorylation of the redox sensitive transcription factor NF-κB. In cell culture, naïve hepatocytes exposed to F1-nano-TiO₂ plasma increased H₂O₂ production. Overnight exposure of these hepatocytes to F1 plasma increased H₂O₂ production capacity in a partially NF-κB dependent manner. Pregnant F1- nano-TiO₂ females exhibited estrogen disruption (12.12 ± 3.1 pg/ml vs. 29.81 ± 8.8 pg/ml sham-control) and vascular dysfunction similar to their directly exposed mothers. F1-nano-TiO₂ uterine artery H₂O₂ production capacity was also elevated twofold. Dysfunctional gestational outcomes in the F1-nano-TiO₂ dams resulted in smaller F1 (10.22 ± 0.6 pups vs. sham-controls 12.71 ± 0.96 pups) and F2 pups (4.93 ± 0.47 g vs. 5.78 ± 0.09 g sham-control pups), and fewer F1 male pups (4.38 ± 0.3 pups vs. 6.83 ± 0.84 sham-control pups).

CONCLUSION

In conclusion, this manuscript provides critical evidence of redox dysregulation across generations following maternal ENM inhalation. Furthermore, dysfunctional gestational outcomes are observed in the F1-nano-TiO₂ generation and impact the development of F2 offspring. In total, this data provides strong initial evidence that maternal ENM exposure has robust biological impacts that persists in at least two generations.

Glucose metabolism enhancement by 10-hydroxy-2-decenoic acid via the PI3K/AKT signaling pathway in high-fat-diet/streptozotocin induced type 2 diabetic mice

Here, we used high fat diet (HFD) combined with streptozotocin (STZ) injection to establish a diabetes model, with the aim of exploring the hypoglycemic effects of 10-hydroxy-2-decenoic acid (10-HDA), and...

Congenital Anomalies Programmed by Maternal Diabetes and Obesity on Offspring of Rats

Embryo-fetal exposure to maternal disorders during intrauterine life programs long-term consequences for the health and illness of offspring. In this study, we evaluated whether mild diabetic rats that were given high-fat/high-sugar (HF/HS) diet presented maternal and fetal changes at term pregnancy. Female rats received citrate buffer (non-diabetic-ND) or streptozotocin (diabetic-D) after birth. According to the oral glucose tolerance test (OGTT), the experimental groups (n = 11 animals/group) were composed of non-diabetic and diabetic receiving standard diet (S) or HF/HS diet. High-fat/high-sugar diet (30% kcal of lard) in chow and water containing 5% sucrose and given 1 month before mating and during pregnancy. During and at the end of pregnancy, obesity and diabetes features were determined. After laparotomy, blood samples, periovarian fat, and uterine content were collected. The diabetic rats presented a higher glycemia and percentage of embryonic losses when compared with the NDS group. Rats DHF/HS presented increased obesogenic index, caloric intake, and periovarian fat weight and reduced gravid uterus weight in relation to the other groups. Besides, this association might lead to the inflammatory process, confirmed by leukocytosis. Obese rats (NDHF/HS and DHF/HS) showed higher triglyceride levels and their offspring with lower fetal weight and ossification sites, indicating intrauterine growth restriction. This finding may contribute to vascular alterations related to long-term hypertensive disorders in adult offspring. The fetuses from diabetic dams showed higher percentages of skeletal abnormalities, and DHF/HS dams still had a higher rate of anomalous fetuses. Thus, maternal diabetes and/or obesity induces maternal metabolic disorders that contribute to affect fetal development and growth.

In Vitro Evaluation of the Toxicological Profile and Oxidative Stress of Relevant Diet-Related Advanced Glycation End Products and Related 1,2-Dicarbonyls

During food processing and storage, and in tissues and fluids under physiological conditions, the Maillard reaction occurs. During this reaction, reactive 1,2-dicarbonyl compounds arise as intermediates that undergo further reactions to form advanced glycation end products (AGEs). Diet is the primary source of exogenous AGEs. Endogenously formed AGEs have been proposed as a risk factor in the pathogenesis of diet-related diseases such as diabetes, insulin resistance, cardiovascular diseases, or chronic disease. AGEs may differently contribute to the diet-related exacerbation of oxidative stress, inflammation, and protein modifications. Here, to understand the contribution of each compound, we tested individually, for the first time, the effect of five 1,2-dicarbonyl compounds 3-deoxyglucosone (3-DG), 3-deoxygalactosone (3-DGal), 3,4-dideoxyglucosone-3-ene (3,4-DGE), glyoxal (GO), and methylglyoxal (MGO) and four different glycated amino acids N-ε-(carboxyethyl)lysine (CEL), N-ε-(carboxymethyl)lysine (CML), methylglyoxal-derived hydroimidazolone-1 (MG-H1), and pyrraline (Pyrr) in a cell line of human keratinocytes (HaCaT). We found that most of the glycated amino acids, i.e., CEL, CML, and MG-H1, did not show any cytotoxicity. At the same time, 1,2-dicarbonyl compounds 3-DGal, 3,4-DGE, GO, and MGO increased the production of reactive oxygen species and induced cell death. MGO induced cell death by apoptosis, whereas 3-DGal and 3,4-DGE induced nuclear translocation of the proinflammatory NF-κB transcription pathway, and the activation of the pyroptosis-related NLRP3 inflammasome cascade. Overall, these results demonstrate the higher toxic impact of 1,2-dicarbonyl compounds on mucosal epithelial cells when compared to glycated amino acids and the selective activation of intracellular signaling pathways involved in the crosstalk mechanisms linking oxidative stress to excessive inflammation.

Deleterious Effects of Overfeeding on Brain Homeostasis and Plasticity in Adult Zebrafish

Overweight and obesity are worldwide epidemic health threats. They recently emerged as disruptors of brain homeostasis leading to a wide variety of neurologic disorders. This study aims at developing a fast and easy overfeeding model using zebrafish for investigating the impact of overweight on brain homeostasis. We established a 4-week overfeeding protocol using commercially available dry food in an ad libitum-like feeding. In the diet-induced obesity/overweight (DIO) fish model, weight, size, and body mass index were increased compared with controls. Also, DIO fish displayed hyperglycemia, and had higher levels of advanced glycation end products and oxidative stress (4-hydroxynonenal [4-HNE]) in a peripheral organ (tail). Although overfed fish did not display major blood-brain barrier leakage, they showed an increased cerebral oxidative stress, blunted brain cell proliferation as well as a striking decreased locomotor activity. Interestingly, switching from an overfeeding to a normal diet partially improved peripheral and central disruptions induced by overfeeding in solely 2 weeks. As a conclusion, this study provides a rapid and easy overfeeding model in zebrafish with relevant peripheral and central disruptions. This model could open the way for further investigations to better understand by which mechanisms overfeeding could disturb brain homeostasis. It also reinforces and contrasts with another zebrafish overweight model, showing that the type of the food provided could impair differently brain homeostasis.

De Novo Development of a Universal Biosensing Platform by Rapid Direct Native Protein Modification

An innovative biosensing assay was developed for simplified, cost-effective, and sensitive detection. By rapid, direct treatment of target proteins with iron porphyrin (TPPFe) in situ, a carboxyl group of amino acid conjugates with an Fe atom of the TPPFe molecule, forming a stable protein complex. We have shown that this complex not only maintains the integrity and functions of original proteins but also acquires peroxidase activity that can turn TMB to a comparably visible signal like that in ELISA. This study is unique since such conversion is difficult to achieve with standard chemical modification or molecular biology methods. In addition, the proposed immunoassay is superior to traditional ELISA as it eliminates an expensive and complicated cross-linking process of an enzyme-labeled antibody. From a practical point of view, we extended this assay to rapid detection of clinically relevant proteins and glucose in blood samples. The results show that this simple immunoassay provides clinical diagnosis, food safety, and environmental monitoring in an easy-to-implement manner.

Advanced glycation end-products disrupt brain microvascular endothelial cell barrier: The role of mitochondria and oxidative stress

During diabetes mellitus, advanced glycation end-products (AGEs) are major contributors to the development of alterations in cerebral capillaries, leading to the disruption of the blood-brain barrier (BBB). Consequently, this is often associated with an amplified oxidative stress response in microvascular endothelial cells. As a model to mimic brain microvasculature, the bEnd.3 endothelial cell line was used to investigate cell barrier function. Cells were exposed to native bovine serum albumin (BSA) or modified BSA (BSA-AGEs). In the presence or absence of the antioxidant compound, N-acetyl-cysteine, cell permeability was assessed by FITC-dextran exclusion, intracellular free radical formation was monitored with H₂DCF-DA probe, and mitochondrial respiratory and redox parameters were analyzed. We report that, in the absence of alterations in cell viability, BSA-AGEs contribute to an increase in endothelial cell barrier permeability and a marked and prolonged oxidative stress response. Decreased mitochondrial oxygen consumption was associated with these alterations and may contribute to reactive oxygen species production. These results suggest the need for further research to explore therapeutic interventions to restore mitochondrial functionality in microvascular endothelial cells to improve brain homeostasis in pathological complications associated with glycation.

Impaired brain homeostasis and neurogenesis in diet-induced overweight zebrafish: a preventive role from A. borbonica extract

Overweight and obesity are worldwide health concerns leading to many physiological disorders. Recent data highlighted their deleterious effects on brain homeostasis and plasticity, but the mechanisms underlying such disruptions are still not well understood. In this study, we developed and characterized a fast and reliable diet-induced overweight (DIO) model in zebrafish, for (1) studying the effects of overfeeding on brain homeostasis and for (2) testing different preventive and/or therapeutic strategies. By overfeeding zebrafish for 4 weeks, we report the disruption of many metabolic parameters reproducing human overweight features including increased body weight, body mass index, fasting blood glucose levels and liver steatosis. Furthermore, DIO fish displayed blood–brain barrier leakage, cerebral oxidative stress, neuroinflammation and decreased neurogenesis. Finally, we investigated the preventive beneficial effects of A. borbonica, an endogenous plant from Reunion Island. Overnight treatment with A. borbonica aqueous extract during the 4 weeks of overfeeding limited some detrimental central effects of DIO. In conclusion, we established a relevant DIO model in zebrafish demonstrating that overfeeding impairs peripheral and central homeostasis. This work also highlights the preventive protective effects of A. borbonica aqueous extracts in DIO, and opens a way to easily screen drugs aiming at limiting overweight and associated neurological disorders.

Enhanced oxidative stress and damage in glycated erythrocytes

Diabetes is associated with a dramatic mortality rate due to its vascular complications. Chronic hyperglycemia in diabetes leads to enhanced glycation of erythrocytes and oxidative stress. Even though erythrocytes play a determining role in vascular complications, very little is known about how erythrocyte structure and functionality can be affected by glycation. Our objective was to decipher the impact of glycation on erythrocyte structure, oxidative stress parameters and capacity to interact with cultured human endothelial cells. In vitro glycated erythrocytes were prepared following incubation in the presence of different concentrations of glucose. To get insight into the in vivo relevance of our results, we compared these data to those obtained using red blood cells purified from diabetics or non-diabetics. We measured erythrocyte deformability, susceptibility to hemolysis, reactive oxygen species production and oxidative damage accumulation. Altered structures, redox status and oxidative modifications were increased in glycated erythrocytes. These modifications were associated with reduced antioxidant defence mediated by enzymatic activity. Enhanced erythrocyte phagocytosis by endothelial cells was observed when cultured with glycated erythrocytes, which was associated with increased levels of phosphatidylserine-likely as a result of an eryptosis phenomenon triggered by the hyperglycemic treatment. Most types of oxidative damage identified in in vitro glycated erythrocytes were also observed in red blood cells isolated from diabetics. These results bring new insights into the impact of glycation on erythrocyte structure, oxidative damage and their capacity to interact with endothelial cells, with a possible relevance to diabetes.

Lycopene in protection against obesity and diabetes: A mechanistic review

Lycopene, a natural pigment that mainly exists in the mature fruit of tomatoes, has gained increasing attention due to its protective effects against obesity and diabetes. The aim of this review is to summarize the potential mechanisms in which lycopene exerts protection against obesity and diabetes, along with highlighting its bioavailability, synthesis and safety. Literature sources used in this review were from the PubMed Database, China Knowledge Resource Integrated Database, China Science and Technology Journal Database, National Science and Technology Library, Wanfang Data, and the Web of Science. For the inquiries, keywords such as lycopene, properties, synthesis, diabetes, obesity, and safety were used in various combinations. About 200 articles and reviews were evaluated. Lycopene exhibits anti-obesity and anti-diabetic activities in different organs and/or tissues, including adipose tissue, liver, kidney, pancreas, brain, ovaries, intestine, and eyes. The underlying mechanism may be attributed to its anti-oxidant and anti-inflammatory properties and through its ability to regulate of AGE/RAGE, JNK/MAPK, PI3K/Akt, SIRT1/FoxO1/PPARγ signaling pathways and AchE activity. The epidemiological investigations support that lycopene consumption may contribute to lowering the risk of obesity and diabetes. The cis-isomers of lycopene are more bioavailable and better absorbed than trans-lycopene, and mainly distribute in liver and adipose tissue. Lycopene exhibits a good margin of safety and can be obtained by plant extraction, chemical synthesis and microbial fermentation. In summary, lycopene consumption beneficially contributes to protecting against diabetes and obesity in animal studies and epidemiological investigations, which supports the potential of this compound as a preventive/therapeutic agent against these disorders. Well-designed, prospective clinical studies are warranted to evaluate the potential therapeutic effect of lycopene against common metabolic diseases.

Antirhea borbonica Aqueous Extract Protects Albumin and Erythrocytes from Glycoxidative Damages

Diabetes constitutes a major health problem associated with severe complications. In hyperglycemic conditions, chronically increased oxidation and glycation of circulating components lead to advanced glycation end-products (AGEs) formation, a key contributor in diabetes complication progression. In line with literature documenting the beneficial properties of herbal teas, this study evaluates the antioxidant/glycant properties of Antirhea borbonica (Ab). Ab aqueous extract effects were tested on human albumin or erythrocytes submitted to methyl glyoxal-mediated glycoxidative damages. By using mass spectrometry, Ab aqueous extracts revealed to be rich in polyphenols. All tested biomarkers of oxidation and glycation, such as AGE, ketoamine, oxidized thiol groups, were decreased in albumin when glycated in the presence of Ab aqueous extract. Ab extract preserve erythrocyte from methylglyoxal (MGO)-induced damages in terms of restored membrane deformability, reduced oxidative stress and eryptosis phenomenon. Antioxidant capacities of Ab extract on erythrocytes were retrieved in vivo in zebrafish previously infused with MGO. These results bring new evidences on the deleterious impacts of glycation on albumin and erythrocyte in diabetes. Furthermore, it reveals antioxidant and antiglycant properties of Ab that could be used for the dietary modulation of oxidative stress and glycation in hyperglycemic situations.

Redox Signaling and Advanced Glycation Endproducts (AGEs) in Diet-Related Diseases

Diets are currently characterized by elevated sugar intake, mainly due to the increased consumption of processed sweetened foods and drinks during the last 40 years. Diet is the main source of advanced glycation endproducts (AGEs). These are toxic compounds formed during the Maillard reaction, which takes place both in vivo, in tissues and fluids under physiological conditions, favored by sugar intake, and ex vivo during food preparation such as baking, cooking, frying or storage. Protein glycation occurs slowly and continuously through life, driving AGE accumulation in tissues during aging. For this reason, AGEs have been proposed as a risk factor in the pathogenesis of diet-related diseases such as diabetes, insulin resistance, cardiovascular diseases, kidney injury, and age-related and neurodegenerative diseases. AGEs are associated with an increase in oxidative stress since they mediate the production of reactive oxygen species (ROS), increasing the intracellular levels of hydrogen peroxide (H₂O₂), superoxide (O₂⁻), and nitric oxide (NO). The interaction of AGEs with the receptor for AGEs (RAGE) enhances oxidative stress through ROS production by NADPH oxidases inside the mitochondria. This affects mitochondrial function and ultimately influences cell metabolism under various pathological conditions. This short review will summarize all evidence that relates AGEs and ROS production, their relationship with diet-related diseases, as well as the latest research about the use of natural compounds with antioxidant properties to prevent the harmful effects of AGEs on health.

Effects of Propolis Extract and Propolis-Derived Compounds on Obesity and Diabetes: Knowledge from Cellular and Animal Models

Propolis is a natural product resulting from the mixing of bee secretions with botanical exudates. Since propolis is rich in flavonoids and cinnamic acid derivatives, the application of propolis extracts has been tried in therapies against cancer, inflammation, and metabolic diseases. As metabolic diseases develop relatively slowly in patients, the therapeutic effects of propolis in humans should be evaluated over long periods of time. Moreover, several factors such as medical history, genetic inheritance, and living environment should be taken into consideration in human studies. Animal models, especially mice and rats, have some advantages, as genetic and microbiological variables can be controlled. On the other hand, cellular models allow the investigation of detailed molecular events evoked by propolis and derivative compounds. Taking advantage of animal and cellular models, accumulating evidence suggests that propolis extracts have therapeutic effects on obesity by controlling adipogenesis, adipokine secretion, food intake, and energy expenditure. Studies in animal and cellular models have also indicated that propolis modulates oxidative stress, the accumulation of advanced glycation end products (AGEs), and adipose tissue inflammation, all of which contribute to insulin resistance or defects in insulin secretion. Consequently, propolis treatment may mitigate diabetic complications such as nephropathy, retinopathy, foot ulcers, and non-alcoholic fatty liver disease. This review describes the beneficial effects of propolis on metabolic disorders.

Pro-oxidant and pro-inflammatory effects of glycated albumin on cardiomyocytes

Human serum albumin (HSA) is the most abundant circulating protein in the body and presents an extensive range of biological functions. As such, it is prone to undergo post-translational modifications (PTMs). The non-enzymatic early glycation of HSA, one of the several PTMs undergone by HSA, arises from the addition of reducing sugars to amine group residues, thus modifying the structure of HSA. These changes may affect HSA functions impairing its biological activity, finally leading to cell damage. The aim of this study was to quantitate glycated-HSA (GA) levels in the plasma of heart failure (HF) patients and to evaluate the biological effects of GA on HL-1 cardiomyocytes. Plasma GA content from HF patients and healthy subjects was measured by direct infusion electrospray ionization mass spectrometry (ESI-MS). Results pointed out a significant increase of GA in HF patients with respect to the control group (p < 0.05). Additionally, after stimulation with GA, proteomic analysis of HL-1 secreted proteins showed the modulation of several proteins involved, among other processes, in the response to stress. Further, stimulated cells showed a rapid increase in ROS generation, higher mRNA levels of the inflammatory cytokine interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α), and higher levels of the oxidative 4-HNE-protein adducts and carbonylated proteins. Our findings show that plasma GA is increased in HF patients. Further, GA exerts pro-inflammatory and pro-oxidant effects on cardiomyocytes, which suggest a causal role in the etiopathogenesis of HF.

Oxidative Stress and Advanced Lipoxidation and Glycation End Products (ALEs and AGEs) in Aging and Age-Related Diseases

Oxidative stress is a consequence of the use of oxygen in aerobic respiration by living organisms and is denoted as a persistent condition of an imbalance between the generation of reactive oxygen species (ROS) and the ability of the endogenous antioxidant system (AOS) to detoxify them. The oxidative stress theory has been confirmed in many animal studies, which demonstrated that the maintenance of cellular homeostasis and biomolecular stability and integrity is crucial for cellular longevity and successful aging. Mitochondrial dysfunction, impaired protein homeostasis (proteostasis) network, alteration in the activities of transcription factors such as Nrf2 and NF-κB, and disturbances in the protein quality control machinery that includes molecular chaperones, ubiquitin-proteasome system (UPS), and autophagy/lysosome pathway have been observed during aging and age-related chronic diseases. The accumulation of ROS under oxidative stress conditions results in the induction of lipid peroxidation and glycoxidation reactions, which leads to the elevated endogenous production of reactive aldehydes and their derivatives such as glyoxal, methylglyoxal (MG), malonic dialdehyde (MDA), and 4-hydroxy-2-nonenal (HNE) giving rise to advanced lipoxidation and glycation end products (ALEs and AGEs, respectively). Both ALEs and AGEs play key roles in cellular response to oxidative stress stimuli through the regulation of a variety of cell signaling pathways. However, elevated ALE and AGE production leads to protein cross-linking and aggregation resulting in an alteration in cell signaling and functioning which causes cell damage and death. This is implicated in aging and various age-related chronic pathologies such as inflammation, neurodegenerative diseases, atherosclerosis, and vascular complications of diabetes mellitus. In the present review, we discuss experimental data evidencing the impairment in cellular functions caused by AGE/ALE accumulation under oxidative stress conditions. We focused on the implications of ALEs/AGEs in aging and age-related diseases to demonstrate that the identification of cellular dysfunctions involved in disease initiation and progression can serve as a basis for the discovery of relevant therapeutic agents.

Protocatechuic and 3,4-Dihydroxyphenylacetic Acids Inhibit Protein Glycation by Binding Lysine through a Metal-Catalyzed Oxidative Mechanism

The mechanism of inhibition of advanced glycation end product (AGE) formation by protocatechuic acid and 3,4-dihydroxyphenylacetic acid (DHPA) has been studied using a widespread applied in vitro model system composed of bovine serum albumin (BSA) and supraphysiological glucose concentrations. Protocatechuic acid and DHPA inhibited the formation of Amadori compounds, fluorescent AGEs (IC₅₀ = 62.1 ± 1.4 and 155.4 ± 1.1 μmol/L, respectively), and N^ε-(carboxymethyl)lysine (IC₅₀ = 535.3 ± 1.1 and 751.2 ± 1.0 μmol/L, respectively). BSA was pretreated with the two phenolic acids, and the formation of BSA-phenolic acid adducts was estimated by nanoflow liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry. Results showed that the tested phenolic acids bound key sites of glycation in BSA through a metal-catalyzed oxidative mechanism. The antiglycative activity mechanism involved the formation of BSA-phenolic acid adducts, and it is unlikely that this occurs in vivo. These results raise the problem to design in vitro models closer to physiological conditions to reach biologically sound conclusions.

The Neonatal Fc Receptor (FcRn): A Misnomer?

Antibodies are essential components of an adaptive immune response. Immunoglobulin G (IgG) is the most common type of antibody found in circulation and extracellular fluids. Although IgG alone can directly protect the body from infection through the activities of its antigen binding region, the majority of IgG immune functions are mediated via proteins and receptors expressed by specialized cell subsets that bind to the fragment crystallizable (Fc) region of IgG. Fc gamma (γ) receptors (FcγR) belong to a broad family of proteins that presently include classical membrane-bound surface receptors as well as atypical intracellular receptors and cytoplasmic glycoproteins. Among the atypical FcγRs, the neonatal Fc receptor (FcRn) has increasingly gained notoriety given its intimate influence on IgG biology and its ability to also bind to albumin. FcRn functions as a recycling or transcytosis receptor that is responsible for maintaining IgG and albumin in the circulation, and bidirectionally transporting these two ligands across polarized cellular barriers. More recently, it has been appreciated that FcRn acts as an immune receptor by interacting with and facilitating antigen presentation of peptides derived from IgG immune complexes (IC). Here we review FcRn biology and focus on newer advances including how emerging FcRn-targeted therapies may affect the immune responses to IgG and IgG IC.

Circulating Oxidative Stress Biomarkers in Clinical Studies on Type 2 Diabetes and Its Complications

Type 2 diabetes (T2DM) and its complications constitute a major worldwide public health problem, with high rates of morbidity and mortality. Biomarkers for predicting the occurrence and development of the disease may therefore offer benefits in terms of early diagnosis and intervention. This review provides an overview of human studies on circulating biomarkers of oxidative stress and antioxidant defence systems and discusses their usefulness from a clinical perspective. Most case-control studies documented an increase in biomarkers of oxidative lipid, protein, and nucleic acid damage in patients with prediabetes and in those with a diagnosis of T2DM compared to controls, and similar findings were reported in T2DM with micro- and macrovascular complications compared to those without. The inconsistence of the results regarding antioxidant defence systems renders difficulty to draw a general conclusion. The clinical relevance of biomarkers of oxidative lipid and protein damage for T2DM progression is uncertain, but prospective studies suggest that markers of oxidative nucleic acid damage such as 8-hydroxy-2'-deoxyguanosine and 8-hydroxyguanosine are promising for predicting macrovascular complications of T2DM. Emerging evidence also points out the relationship between serum PON1 and serum HO1 in T2DM and its complications. Overall, enhanced oxidative damage represents an underlying mechanism of glucose toxicity in T2DM and its related micro- and macrovascular complications suggesting that it may be considered as a potential additional target for pharmacotherapy. Therefore, further studies are needed to understand whether targeting oxidative stress may yield clinical benefits. In this view, the measurement of oxidative stress biomarkers in clinical trials deserves to be considered as an additional tool to currently used parameters to facilitate a more individualized treatment of T2DM in terms of drug choice and patient selection.

Advanced glycation end-products disrupt human endothelial cells redox homeostasis: new insights into reactive oxygen species production

Advanced glycation end-products (AGEs) trigger multiple metabolic disorders in the vessel wall that may in turn lead to endothelial dysfunction. The molecular mechanisms by which AGEs generate these effects are not completely understood. Oxidative stress plays a key role in the development of deleterious effects that occur in endothelium during diabetes. Our main objectives were to further understand how AGEs contribute to reactive oxygen species (ROS) overproduction in endothelial cells and to evaluate the protective effect of an antioxidant plant extract. The human endothelial cell line EA.hy926 was treated with native or modified bovine serum albumin (respectively BSA and BSA-AGEs). To monitor free radicals formation, we used H₂DCF-DA, dihydroethidium (DHE), DAF-FM-DA and MitoSOX Red dyes. To investigate potential sources of ROS, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and mitochondrial inhibitors were used. The regulation of different types of ROS by the polyphenol-rich extract from the medicinal plant Doratoxylon apetalum was also studied for a therapeutic perspective. BSA-AGEs exhibited not only less antioxidant properties than BSA, but also pro-oxidant effects. The degree of albumin glycoxidation directly influenced oxidative stress through a possible communication between NADPH oxidase and mitochondria. D. apetalum significantly decreased intracellular hydrogen peroxide and superoxide anions mainly detected by H₂DCF-DA and DHE respectively. Our results suggest that BSA-AGEs promote a marked oxidative stress mediated at least by NADPH oxidase and mitochondria. D. apetalum plant extract appeared to be an effective antioxidant compound to protect endothelial cells.

Hyperglycemia modulates redox, inflammatory and vasoactive markers through specific signaling pathways in cerebral endothelial cells: Insights on insulin protective action

Type 2 diabetes is associated with major vascular dysfunctions, leading to clinical complications such as stroke. It is also known that hyperglycemia dysregulates blood-brain barrier homeostasis by altering cerebral endothelial cell function. Oxidative stress may play a critical role. The aim of this study was to evaluate the effect of hyperglycemia and insulin on the production of redox, inflammatory and vasoactive markers by cerebral endothelial cells. Murine bEnd.3 cerebral endothelial cells were exposed to hyperglycemia in the presence or not of insulin. Results show that hyperglycemia altered the expression of genes encoding the ROS-producing enzyme Nox4, antioxidant enzymes Cu/ZnSOD, catalase and HO-1 as well as Cu/ZnSOD, MnSOD and catalase enzymatic activities, leading to a time-dependent modulation of ROS levels. Cell preconditioning with inhibitors targeting PI3K, JNK, ERK, p38 MAPK or NFĸB signaling molecules partly blocked hyperglycemia-induced oxidative stress. Conversely, AMPK inhibitor exacerbated ROS production, suggesting a protective role of AMPK on the antioxidant defense system. Hyperglycemia also modulated both gene expression and nuclear translocation of the redox-sensitive transcription factor Nrf2. Moreover, hyperglycemia caused a pro-inflammatory response by activating NFĸB-AP-1 pathway and IL-6 secretion. Hyperglycemia reduced eNOS gene expression and NO levels, while increasing ET-1 gene expression. Importantly, insulin counteracted all the deleterious effects of hyperglycemia. Collectively, these results demonstrate that hyperglycemia dysregulated redox, inflammatory and vasoactive markers in cerebral endothelial cells. Insulin exerted a protective action against hyperglycemia effects. Thus, it will be of high interest to evaluate the benefits of antioxidant and anti-inflammatory strategies against hyperglycemia-mediated vascular complications in type 2 diabetes.

Glycation of human serum albumin impairs binding to the glucagon-like peptide-1 analogue liraglutide

The long-acting glucagon-like peptide-1 analogue liraglutide has proven efficiency in the management of type 2 diabetes and also has beneficial effects on cardiovascular diseases. Liraglutide's protracted action highly depends on its capacity to bind to albumin via its palmitic acid part. However, in diabetes, albumin can undergo glycation, resulting in impaired drug binding. Our objective in this study was to assess the impact of human serum albumin (HSA) glycation on liraglutide affinity. Using fluorine labeling of the drug and ¹⁹F NMR, we determined HSA affinity for liraglutide in two glycated albumin models. We either glycated HSA in vitro by incubation with glucose (G25- or G100-HSA) or methylglyoxal (MGO-HSA) or purified in vivo glycated HSA from the plasma of diabetic patients with poor glycemic control. Nonglycated commercial HSA (G0-HSA) and HSA purified from plasma of healthy individuals served as controls. We found that glycation decreases affinity for liraglutide by 7-fold for G100-HSA and by 5-fold for MGO-HSA compared with G0-HSA. A similarly reduced affinity was observed for HSA purified from diabetic individuals compared with HSA from healthy individuals. Our results reveal that glycation significantly impairs HSA affinity to liraglutide and confirm that glycation contributes to liraglutide's variable therapeutic efficiency, depending on diabetes stage. Because diabetes is a progressive disease, the effect of glycated albumin on liraglutide affinity found here is important to consider when diabetes is managed with this drug.

Serum Antioxidant Parameters are Significantly Increased in Patients with Type 2 Diabetes Mellitus after Consumption of Chinese Propolis: A Randomized Controlled Trial Based on Fasting Serum Glucose Level

INTRODUCTION

Propolis is a natural product with many biological activities. The present study was designed to evaluate the effects of Chinese propolis on glucose metabolism, antioxidant function, and inflammatory cytokines in patients with type 2 diabetes mellitus (T2DM).

METHODS

In the 18-week study, recruited T2DM patients were randomly divided into a Chinese propolis group (900 mg/day) (n = 31) and a control group (n = 30) according to fasting serum glucose levels at baseline.

RESULTS

At the end of the study, no significant difference was found between the groups in serum glucose, glycosylated hemoglobin, insulin, aldose reductase, or adiponectin. However, serum GSH, flavonoids, and polyphenols were significantly increased, and serum lactate dehydrogenase activity was significantly reduced in the Chinese propolis group. Meanwhile, serum IL-6 was significantly increased in the Chinese propolis group.

CONCLUSION

Chinese propolis is effective at improving antioxidant function in T2DM patients, partly by increasing serum antioxidant parameters.

IL-18 polymorphisms contribute to hepatitis B virus-related cirrhosis and hepatocellular carcinoma susceptibility in Chinese population: a case-control study

IL-18 polymorphisms influence the transcriptional activity of the IL-18 gene and associated with various diseases. However, their relationships with hepatitis B virus-related liver diseases had not reached a consensus. So we conducted this case-control study with a view to clarifying the association. We included four groups: healthy controls, chronic hepatitis B virus (CHB) carriers, liver cirrhosis (LC) and hepatocellular carcinoma (HCC) groups with each group of 250 persons. Odd ratios (ORs) and 95% confidence intervals (95%CIs) with or without adjustment were calculated. Haplotype analysis was also performed. The results showed people carrying rs187238 CG genotype had a lower risk of LC (CG vs. CC: OR = 0.59, 95%CI = 0.38–0.91, P = 0.02), while GG genotype carriers had a higher risk of HCC (GG vs. CC+CG: OR = 4.73, 95%CI = 1.01–22.1, P = 0.03) than those with CC and CG genotypes in healthy group. Rs187238 GG genotype increased the risk from CHB to LC status (GG vs. CC: OR = 4.81, 95%CI = 1.03–22.6; GG vs. CC+CG: OR = 4.73, 95%CI = 1.01–22.1), meanwhile the trend also existed by controlling confounding factors (GG vs. CC: OR = 6.25, 95%CI = 1.09–35.8; GG vs. CC+CG: OR = 5.91, 95%CI = 1.04–33.7). Haplotype Crs187238Trs1946518 moderately decreased the risk of CHB carriers developing into HCC (OR = 0.69, 95%CI = 0.50–0.96, P = 0.03) after adjustment. In conclusion, IL-18 rs187238 GG genotype may increase the risk of HCC in healthy population and the risk of LC in CHB carriers.