The association of enzymatic and non-enzymatic antioxidant defense parameters with inflammatory markers in patients with exudative form of age-related macular degeneration

Deciphering the associations of selenium distribution in serum GPx-3 and selenoprotein P with cardiovascular risk factors in a healthy population with moderate levels of selenium: The ATTICA study

BACKGROUND

Selenium (Se) is an essential micronutrient, important for human health. The relationship of Se with cardiovascular risk factors is still inconclusive, especially regarding the role of different selenoproteins. The present study evaluated the relation of total serum Se as well as its distribution in plasma selenoproteins, namely glutathione peroxidase 3 (GPx3) and selenoprotein P (SelP) with cardiovascular risk factors in a sex-specific manner, in a healthy population with moderate levels of Se.

METHODS

A sub-sample from the ATTICA Study's database, consisting of 398 participants (160 females and 238 males) with data on Se and selenoproteins levels, was considered. GPx3, SelP and the main non-specific serum selenium containing protein, selenoalbumin (SeAlb) were simultaneously determined in human plasma by high-performance liquid chromatography (HPLC) coupled with inductively coupled plasma mass spectrometry (ICP-MS) at baseline.

RESULTS

Participants that belong to the highest tertiles of GPx3 and SelP presented the lowest blood pressure. Homocysteine was inversely associated with SelP and its ratio SelP/TSe in both sexes. In males, the lowest tertile of GPx3 showed lower adiponectin levels (0.66 ± 0.21 μg/mL) in comparison to the 2nd tertile of GPx3 (p=0.002), SelP was inversely associated with visceral adipose index (VAI) (-2.29 ± 0.81, p=0.005). Particularly, in males, the middle tertile of SelP had the lowest VAI values. Regarding females, lower Lp(a) concentration by 11.96 ± 5.84 mg/dL was observed in low SelP levels while higher leptin concentration by 2.30 ± 0.73 μg/L and lower fibrinogen concentration by 27.32 ± 13.30 mg/dL was detected in low GPx3 levels.

CONCLUSION

Circulating selenoproteins exert differentiated effects on cardiovascular risk factors, some of them in a sex-specific manner.

Mitochondrial Dysfunction: A Key Player in Brain Aging and Diseases

Mitochondria are thought to have become incorporated within the eukaryotic cell approximately 2 billion years ago and play a role in a variety of cellular processes, such as energy production, calcium buffering and homeostasis, steroid synthesis, cell growth, and apoptosis, as well as inflammation and ROS production. Considering that mitochondria are involved in a multitude of cellular processes, mitochondrial dysfunction has been shown to play a role within several age-related diseases, including cancers, diabetes (type 2), and neurodegenerative diseases, although the underlying mechanisms are not entirely understood. The significant increase in lifespan and increased incidence of age-related diseases over recent decades has confirmed the necessity to understand the mechanisms by which mitochondrial dysfunction impacts the process of aging and age-related diseases. In this review, we will offer a brief overview of mitochondria, along with structure and function of this important organelle. We will then discuss the cause and consequence of mitochondrial dysfunction in the aging process, with a particular focus on its role in inflammation, cognitive decline, and neurodegenerative diseases, such as Huntington's disease, Parkinson's disease, and Alzheimer's disease. We will offer insight into therapies and interventions currently used to preserve or restore mitochondrial functioning during aging and neurodegeneration.

Antioxidative Role of Heterophagy, Autophagy, and Mitophagy in the Retina and Their Association with the Age-Related Macular Degeneration (AMD) Etiopathogenesis

Age-related macular degeneration (AMD), an oxidative stress-linked neurodegenerative disease, leads to irreversible damage of the central retina and severe visual impairment. Advanced age and the long-standing influence of oxidative stress and oxidative cellular damage play crucial roles in AMD etiopathogenesis. Many authors emphasize the role of heterophagy, autophagy, and mitophagy in maintaining homeostasis in the retina. Relevantly modifying the activity of both macroautophagy and mitophagy pathways represents one of the new therapeutic strategies in AMD. Our review provides an overview of the antioxidative roles of heterophagy, autophagy, and mitophagy and presents associations between dysregulations of these molecular mechanisms and AMD etiopathogenesis. The authors performed an extensive analysis of the literature, employing PubMed and Google Scholar, complying with the 2013-2023 period, and using the following keywords: age-related macular degeneration, RPE cells, reactive oxygen species, oxidative stress, heterophagy, autophagy, and mitophagy. Heterophagy, autophagy, and mitophagy play antioxidative roles in the retina; however, they become sluggish and dysregulated with age and contribute to AMD development and progression. In the retina, antioxidative roles also play in RPE cells, NFE2L2 and PGC-1α proteins, NFE2L2/PGC-1α/ARE signaling cascade, Nrf2 factor, p62/SQSTM1/Keap1-Nrf2/ARE pathway, circulating miRNAs, and Yttrium oxide nanoparticles performed experimentally in animal studies.

Uncovering the Relationship between Selenium Status, Age, Health, and Dietary Habits: Insights from a Large Population Study including Nonagenarian Offspring from the MARK-AGE Project

An inadequate selenium (Se) status can accelerate the aging process, increasing the vulnerability to age-related diseases. The study aimed to investigate plasma Se and Se species in a large population, including 2200 older adults from the general population (RASIG), 514 nonagenarian offspring (GO), and 293 GO Spouses (SGO). Plasma Se levels in women exhibit an inverted U-shaped pattern, increasing with age until the post-menopausal period and then declining. Conversely, men exhibit a linear decline in plasma Se levels with age. Subjects from Finland had the highest plasma Se values, while those from Poland had the lowest ones. Plasma Se was influenced by fish and vitamin consumption, but there were no significant differences between RASIG, GO, and SGO. Plasma Se was positively associated with albumin, HDL, total cholesterol, fibrinogen, and triglycerides and negatively associated with homocysteine. Fractionation analysis showed that Se distribution among plasma selenoproteins is affected by age, glucometabolic and inflammatory factors, and being GO or SGO. These findings show that sex-specific, nutritional, and inflammatory factors play a crucial role in the regulation of Se plasma levels throughout the aging process and that the shared environment of GO and SGO plays a role in their distinctive Se fractionation.

Royal jelly plus coenzyme Q10 supplementation improves high-intensity interval exercise performance via changes in plasmatic and salivary biomarkers of oxidative stress and muscle damage in swimmers: a randomized, double-blind, placebo-controlled pilot trial

Background

Excessive production of free radicals caused by many types of exercise results in oxidative stress, which leads to muscle damage, fatigue, and impaired performance. Supplementation with royal jelly (RJ) or coenzyme Q10 (CoQ10) has been shown to attenuate exercise-induced oxidant stress in damaged muscle and improve various aspects of exercise performance in many but not all studies. Nevertheless, the effects of treatments based on RJ plus CoQ10 supplementation, which may be potentially beneficial for reducing oxidative stress and enhancing athletic performance, remain unexplored. This study aimed to examine whether oral RJ and CoQ10 co-supplementation could improve high-intensity interval exercise (HIIE) performance in swimmers, inhibiting exercise-induced oxidative stress and muscle damage.

Methods

Twenty high-level swimmers were randomly allocated to receive either 400 mg of RJ and 60 mg of CoQ10 (RJQ) or matching placebo (PLA) once daily for 10 days. Exercise performance was evaluated at baseline, and then reassessed at day 10 of intervention, using a HIIE protocol. Diene conjugates (DC), Schiff bases (SB), and creatine kinase (CK) were also measured in blood plasma and saliva before and immediately after HIIE in both groups.

Results

HIIE performance expressed as number of points according to a single assessment system developed and approved by the International Swimming Federation (FINA points) significantly improved in RJQ group (p = 0.013) compared to PLA group. Exercise-induced increase in DC, SB, and CK levels in plasma and saliva significantly diminished only in RJQ group (p < 0.05). Regression analysis showed that oral RJQ administration for 10 days was significantly associated with reductions in HIIE-induced increases in plasmatic and salivary DC, SB, and CK levels compared to PLA. Principal component analysis revealed that swimmers treated with RJQ are grouped by both plasmatic and salivary principal components (PC) into a separate cluster compared to PLA. Strong negative correlation between the number of FINA points and plasmatic and salivary PC1 values was observed in both intervention groups.

Conclusion

The improvements in swimmers’ HIIE performance were due in significant part to RJQ-induced reducing in lipid peroxidation and muscle damage in response to exercise. These findings suggest that RJQ supplementation for 10 days is potentially effective for enhancing HIIE performance and alleviating oxidant stress.

Abbreviations

RJ, royal jelly; CoQ10, coenzyme Q10; HIIE, high-intensity interval exercise; DC, diene conjugates; SB, Schiff bases; CK, creatine kinase; RJQ, royal jelly plus coenzyme Q10; PLA, placebo; FINA points, points according to a single assessment system developed and approved by the International Swimming Federation; ROS, reactive oxygen species; 10H2DA, 10-hydroxy-2-decenoic acid; AMPK, 5′-AMP-activated protein kinase; FoxO3, forkhead box O3; MnSOD, manganese-superoxide dismutase; CAT, catalase; E, optical densities; PCA, principal component analysis; PC, principal component; MCFAs, medium-chain fatty acids; CaMKKβ, Ca²⁺/calmodulin-dependent protein kinase β; TBARS, thiobarbituric acid reactive substances; MDA, malondialdehyde.

Investigation of the Clinical Laboratory Indexes in COVID-19 Patients with Ocular Symptoms in Iran: A Single-Center Experience

Objectives: Ocular symptoms are prevalent in coronavirus infectious disease 2019 (COVID-19) patients, which may be related to clinical/paraclinical conditions. This study investigated the association between laboratory indexes and ocular symptoms in COVID-19 patients. Methods: In this cross-sectional study, 108 polymerase chain reaction (PCR)-confirmed COVID-19 patients admitted to the Rouhani Hospital, Babol, Iran, were enrolled. Ocular symptoms were investigated using standard ophthalmologic examinations. Routine laboratory investigation was done according to the standard management in patients with COVID-19 infection. Results: The erythrocyte sedimentation rate (ESR) and the serum levels of the blood urea nitrogen (BUN) and creatinine (Cr) were significantly higher in COVID-19 patients with ocular discharge and exudate (P = 0.002, 0.045, 0.046, and 0.027, respectively), while the red blood cell (RBC) and albumin were lower in COVID-19 patients with ocular discharge and exudate (P = 0.029 and 0.027, respectively). The serum levels of creatine kinase (CPK) and iron (Fe) were significantly higher in non-photophobic COVID-19 patients than in photophobic patients (P =0.033 and 0.050, respectively). In contrast, the serum level of procalcitonin was lower than photophobic COVID-19 patients (P = 0.024). The serum level of phosphorus (P) was significantly higher in COVID-19 patients with itchy eyes compared to COVID-19 patients without itchy eyes (P = 0.026). Conclusions: The footprint of laboratory indexes was demonstrated in ocular symptoms of COVID-19 patients. The kidney biomarkers were correlated with ocular discharge and exudate, and electrolytes were associated with tear-related symptoms.

Therapeutic Potential of Selected Medicinal Plants Against Carrageenan Induced Inflammation in Rats

The current study was aimed to analyze the therapeutic effect of selected medicinal plants, that is, Curcuma longa, Zingiber officinale, Trigonella graceum-foenum, Nigella sativa, and Syzygium aromaticum against carrageenan-induced oxidative stress and inflammation in rats. Phytochemical analysis revealed the presence of diverse range of bioactives. IC₅₀ values for antioxidant assays including DPPH (2,2-diphenyl-1-picrylhydrazyl), metal chelating, ABTS scavenging (2, 2^′-Azino-Bis-3-Ethylbenzothiazoline-6-Sulfonic Acid), β-carotene bleaching, and H₂O₂ (hydrogen peroxide) scavenging ranged from 37-294, 71-243.4, 69.66-191.8, 98.92-228.5, and 82-234.9 μg/mL, respectively. All tested plants extract were found active against tested pathogenic microorganisms with lowest minimum inhibitory concentrations. Oral administration of tested plants extracts in different doses (250, 500, and 1000 mg/kg b. w) did not exhibit any toxicological effects on hemato-biochemical profile of treated rats in comparison to control group rats. Further, plants extract exhibited considerable anti-inflammatory activity in rats paw inflammation and decreased cellular infiltration to inflammatory site in dose dependent manner. Pretreatment of animals with tested plants extract (100, 200, and 400 mg/kg b. w.) caused significant alteration in total antioxidants, oxidants, and enzymes activities in paw tissue homogenate and the effect was more pronounced at higher concentration (400 mg/kg b. w.). Results showed that tested plants extract are rich source of diverse classes of phenolics and have therapeutic potential against oxidative stress and inflammation.

N-acetyl-L-cysteine Improves the Developmental Competence of Bovine Oocytes and Embryos Cultured In Vitro by Attenuating Oxidative Damage and Apoptosis

Oxidative stress has been suggested to negatively affect oocyte and embryo quality and developmental competence, resulting in failure to reach full term. In this study, we investigated the effect of N-acetyl-L-cysteine (NAC), a cell-permeating antioxidant, on developmental competence and the quality of oocytes and embryos upon supplementation (0.1–10 mM) in maturation and culture medium in vitro using slaughterhouse-derived oocytes and embryos. The results show that treating oocytes with 1.0 mM NAC for 8 h during in vitro maturation attenuated the intracellular reactive oxygen species (ROS) (p < 0.05) and upregulated intracellular glutathione levels (p < 0.01) in oocytes. Interestingly, we found that NAC affects early embryonic development, not only in a dose-dependent, but also in a stage-specific, manner. Significantly (p < 0.05) decreased cleavage rates (90.25% vs. 81.46%) were observed during the early stage (days 0–2), while significantly (p < 0.05) increased developmental rates (38.20% vs. 44.46%) were observed during the later stage (from day 3) of embryonic development. In particular, NAC supplementation decreased the proportion of apoptotic blastomeres significantly (p < 0.05), resulting in enhanced hatching capability and developmental rates during the in vitro culture of embryos. Taken together, our results suggest that NAC supplementation has beneficial effects on bovine oocytes and embryos through the prevention of apoptosis and the elimination of oxygen free radicals during maturation and culture in vitro.

A Randomized Study of Nutritional Supplementation in Patients with Unilateral Wet Age-Related Macular Degeneration

The purpose of this study is evaluate the efficacy and safety of medicinal products containing the original Age-Related Eye Disease group (AREDS) formulation at doses approved in Europe (EU, control group; n = 59) with a product that adds DHA, lutein, zeaxanthin, resveratrol and hydroxytyrosol to the formula (intervention group; n = 50). This was a multicenter, randomized, observer-blinded trial conducted in patients aged 50 years or older diagnosed with unilateral exudative Age related Macular Degeneration AMD. At month 12, the intervention did not have a significant differential effect on visual acuity compared with the control group, with an estimated treatment difference in Early Treatment Diabetic Retinopathy Study (ETDRS) of −1.63 (95% CI −0.83 to 4.09; p = 0.192). The intervention exhibited a significant and, in most cases, relevant effect in terms of a reduction in some inflammatory cytokines and a greater improvement in the fatty acid profile and serum lutein and zeaxantin concentration. In patients with unilateral wet AMD, the addition of lutein, zeaxanthin, resveratrol, hydroxytyrosol and DHA to the AREDS EU recommended doses in the short-term did not have a differential effect on visual acuity compared to a standard AREDS EU formula but, in addition to improving the fatty acid profile and increasing carotenoid serum levels, may provide a beneficial effect in improving the proinflammatory and proangiogenic profile of patients with AMD.

Macrocycles and Supramolecules as Antioxidants: Excellent Scaffolds for Development of Potential Therapeutic Agents

Oxidative stress due to the high levels of reactive oxygen species (ROS) that damage biomolecules (lipids, proteins, DNA) results in acute inflammation. However, without proper intervention, acute inflammation progresses to chronic inflammation and then to several chronic diseases, including cancer, myocardial infarction, cardiovascular diseases, chronic inflammation, atherosclerosis, and more. There has been extensive research on the antioxidants of natural origin. However, there are myriad possibilities for the development of synthetic antioxidants for pharmacological applications. There is an increasing interest in the identification of novel synthetic antioxidants for the modulation of biochemical processes related to ROS. In this regard, derivatives of supramolecules, such as calix[n]arene, resorcinarene, calixtyrosol, calixpyrrole, cucurbit[n]uril, porphyrin etc. are gaining attention for their abilities to scavenge the free radicals. Supramolecular chemistry offers excellent scaffolds for the development of novel antioxidants that can be used to modulate free radical reactions and to improve the disorders related to oxidative stress. This review focuses on the interdisciplinary approach for the design and development of novel synthetic antioxidants based on supramolecular scaffolds, with potentially protective effects against oxidative stress.

Oxidative stress accelerates the carotid atherosclerosis process in patients with chronic kidney disease

INTRODUCTION

The atherosclerosis process is highly accelerated in patients with chronic kidney disease (CKD). Oxidative stress is considered as one of the pro-atherogenic factors involved in accelerating the atherosclerosis process of the carotid artery. The aim of the present study was to determine the relationship between oxidative stress markers and the progression of carotid atherosclerosis in CKD patients.

MATERIAL AND METHODS

The study was conducted on 162 patients with CKD and 40 controls, and the disease stage was scored between 2 and 5D. Blood samples were taken and advanced oxidative protein product, myeloperoxidases, malondialdehyde, nitric oxide, glutathione, and oxidised low-density lipoprotein were measured. Furthermore, we studied the correlations between these biomarkers and clinical and para-clinical cardiovascular complications.

RESULTS

The average age of patients was 56.5 years. The oxidative stress markers average ± SD levels in CKD groups compared to the control were as follows: advanced oxidation protein product (61.89 ±1.4 vs. 26.65 ±1.05 µmol/l), myeloperoxidase (59.89 ±1.98 vs. 38.45 ±1.98 UI/ml), malondialdehyde (6.1 ±0.12 vs. 3.26 ±0.03 µmol/l), nitric oxide (65.82 ±1.06 vs. 52.19 ±2.1 µmol/l), glutathione (52.21 ±1.3 vs. 89.4 ±2.6 IU/ml), and oxLDL (15.57 ±1.07 vs. 1.72 ±0.82 µmol/l). While the glutathione level decreased significantly in advanced CKD stage (p < 0.05), the concentrations of all the other biomarkers increased significantly in accordance with CKD score (p < 0.05).

CONCLUSIONS

Cardiovascular diseases, mainly atherosclerosis, can be diagnosed indirectly by measuring oxidative stress markers. Furthermore, theses markers can be used to predict the progression of CKD, for better management of the disease.

Systemic levels of C-reactive protein in patients with age-related macular degeneration: A systematic review with meta-analyses

Ageing of the retina is associated with the gradual accumulation of basal deposits and the formation of drusen. However, in some individuals this process is exacerbated and causes development of age-related macular degeneration. Late features of age-related macular degeneration include geographic atrophy of the neuroretina or choroidal neovascularization. Such changes lead to blurred vision, metamorphopsia, and scotoma, and is the leading cause of vision loss in developed countries. Chronic low-grade inflammation has been investigated because of its relationship to ageing and its role in the gap between chronological and biological ageing. Here, we systematically reviewed studies investigating systemic C-reactive protein in patients with age-related macular degeneration. We identified 53 studies with 60,598 participants (10,392 patients and 38,901 controls). Our meta-analyses revealed that early age-related macular degeneration was not associated to systemic C-reactive protein (Cohen's d = 0.03 [-0.04 to 0.10]; OR = 1.06 [0.93-1.20]; P = 0.39) whereas late age-related macular degeneration (Cohen's d = 0.38 [0.24 to 0.51]; OR = 1.99 [1.55-2.52]; P < 0.0001), and neovascular age-related macular degeneration (Cohen's d = 0.40 [0.24 to 0.56]; OR = 2.07 [1.55-2.76]; P < 0.0001) was associated with a small-to-moderate increase in systemic C-reactive protein. Our review provides an overview of this extensively studied field, provide summary estimates that provide insight into when and to what extent systemic C-reactive protein is associated with age-related macular degeneration, and help in distinguishing the potentially reversible disease processes from that of irreversible retinal ageing.

Systemic levels of interleukin-6 in patients with age-related macular degeneration: a systematic review and meta-analysis

Age-related macular degeneration (AMD) is the most prevalent cause of irreversible vision loss in industrialized countries. Several studies have investigated systemic interleukin-6 (IL-6) levels of patients with AMD. In this study, we systemically reviewed the literature to provide an overview of the field and used meta-analyses to provide a summary estimate of the standardized mean difference (SMD) of systemic IL-6 between patients with AMD and control individuals. We searched the literature databases PubMed/MEDLINE, Embase, Web of Science and the Cochrane Central on 1 June 2019 for relevant studies on humans. Two authors independently extracted data and evaluated risk of bias. We identified 19 studies for the qualitative review with a total of more than 3586 individuals (1865 controls and 1721 with AMD). We found an overall random-effects SMD in systemic IL-6 levels 0.63 (95% CI: 0.28 to 0.99, p = 0.0005) corresponding to a medium effect size. In a subgroup analysis, we found that early AMD was not strongly associated with elevated IL-6 levels (0.12, 95% CI: -0.01 to 0.24, p = 0.06), which was in contrast to the significantly elevated IL-6 levels in patients with geographic atrophy (1.21, 95% CI: 0.41 to 2.01, p = 0.003) and patients with neovascular AMD (0.99, 95% CI: 0.34 to 1.63, p = 0.003). Our results show that the evidence today suggests an increased systemic IL-6 in patients with AMD, but that this may be a phenomenon more closely related to the late subtypes of AMD.

DNA Damage Response and Oxidative Stress in Systemic Autoimmunity

The DNA damage response and repair (DDR/R) network, a sum of hierarchically structured signaling pathways that recognize and repair DNA damage, and the immune response to endogenous and/or exogenous threats, act synergistically to enhance cellular defense. On the other hand, a deregulated interplay between these systems underlines inflammatory diseases including malignancies and chronic systemic autoimmune diseases, such as systemic lupus erythematosus, systemic sclerosis, and rheumatoid arthritis. Patients with these diseases are characterized by aberrant immune response to self-antigens with widespread production of autoantibodies and multiple-tissue injury, as well as by the presence of increased oxidative stress. Recent data demonstrate accumulation of endogenous DNA damage in peripheral blood mononuclear cells from these patients, which is related to (a) augmented DNA damage formation, at least partly due to the induction of oxidative stress, and (b) epigenetically regulated functional abnormalities of fundamental DNA repair mechanisms. Because endogenous DNA damage accumulation has serious consequences for cellular health, including genomic instability and enhancement of an aberrant immune response, these results can be exploited for understanding pathogenesis and progression of systemic autoimmune diseases, as well as for the development of new treatments.

Effects of dietary grape seed polyphenols supplementation during late gestation and lactation on antioxidant status in serum and immunoglobulin content in colostrum of multiparous sows1

The aim of this study was to determine the effects of dietary grape seed polyphenols (GSP) supplementation during the late gestation and lactation period on reproductive performance, antioxidative status in serum, nutrient composition, and Ig content in colostrum of multiparous sows. On day 80 of gestation, a total of 64 sows with similar body condition were allocated to a completely randomized block design with 4 dietary treatments (n = 16 sows per treatment): 1) basal diet (CON, control group); 2) basal diet supplemented with 200 IU/kg vitamin E (200VE, positive control group); 3) basal diet supplemented with 200 mg/kg GSP (200GSP); and 4) basal diet supplemented with 300 mg/kg GSP (300GSP). The trial lasted 56 d until the piglets were weaned on day 21 of lactation. Reproductive performance, parameters of antioxidative status, and levels of progesterone (P4) and estradiol (E2) in serum, nutrient composition, and Ig content in colostrum of sows were determined. The number of dead fetuses was reduced, and farrowing survival was significantly improved in the litters from 300GSP-fed (P < 0.05). Preweaning survivability significantly increased in the litters from sows fed 200GSP and 200VE (P < 0.05). The activity of superoxide dismutase and glutathione peroxidase (GSH-Px) in the serum was significantly increased in sows fed 200GSP and 300GSP (P < 0.05). The activity of GSH-Px in the serum also significantly increased in sows fed 200VE (P < 0.05). Sows fed 300GSP had the greatest levels of P4 and E2 in the serum, which was significantly greater than sows fed 200VE and CON (P < 0.05). No significant differences were found among treatments for the content of solids-not-fat, fat, protein, and lactose in colostrum (P > 0.05). However, sows fed GSP had greater IgM and IgG content in colostrum compared with sows fed 200VE and CON (P < 0.05). In conclusion, dietary GSP supplementation during late gestation and lactation improved the farrowing survival and preweaning survivability, enhanced the antioxidant status and hormone levels in serum, and increased the IgM and IgG content in colostrum of sows.

Systemic Levels of Interleukin-6 Correlate With Progression Rate of Geographic Atrophy Secondary to Age-Related Macular Degeneration

Purpose

Geographic atrophy (GA) is a clinical phenotype of late age-related macular degeneration (AMD) with no current treatment available. In this study, we investigated markers of chronic inflammation in plasma of patients with GA and how these relate to progression rate.

Methods

We prospectively included 42 patients with GA, 41 patients with neovascular AMD, and 27 healthy controls. We quantified levels of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF) receptor 2, and C-reactive protein (CRP). We adapted an inflammation summary score to cluster conceptually related markers of chronic inflammation. Enlargement rate of the atrophic lesion was measured from fundus autofluorescence images performed at baseline and after 1 year.

Results

Patients with GA showed an increase in proinflammatory markers of IL-6 (P = 0.009), TNF receptor 2 (P = 0.013), and CRP (P = 0.017) compared to healthy controls. We found that IL-8 levels were markedly higher in patients with GA when compared to patients with neovascular AMD (P = 0.013). The inflammation summary score was high in patients with neovascular AMD (P = 0.024), but even higher in patients with GA (<0.001), when compared to healthy controls. GA enlargement was measured in 36 patients, who completed follow-up. Plasma levels of IL-6 had a moderate but significant correlation with GA enlargement rate (R2 = 0.23, P = 0.0035).

Conclusions

Markers of chronic inflammation strongly associates with presence of GA secondary to AMD. Plasma IL-6 possesses predictive ability of progression and constitutes the first known plasma biomarker of disease activity in GA. These findings shed light into a poorly understood clinical phenotype of AMD and highlights the important role of chronic inflammation in GA.

Associations between CYP2J2 (-76G>T) rs890293 polymorphism and age-related macular degeneration

Backgroung. Age-related macular degeneration (AMD) is a disease of the macula, which significantly affects the eyesight and leads to irreversible central vision loss. The etiopathogenesis of AMD is still not absolutely clear. It is thought that age-related macular degeneration has a multifactorial etiology, the development of which may be caused by interrelation of environmental with innate factors, while genetic factors also have an impact. Macular degenerative changes occur due to the formation of drusen, about 40% of which is lipids. As the CYP2J2 gene is involved in the metabolism of lipids, it was selected for investigation in this study.

PURPOSE

To determine the relation between early stage and exudative AMD and CYP2J2 (-76G>T) gene rs890293 polymorphism in a Lithuanian population.

METHODS

The study enrolled 204 patients with early AMD, 197 patients with exudative AMD and 198 healthy controls. Samples of DNA from peripheral white blood cells were purified using commercial kits. The genotyping was carried out using a real-time PCR method.

RESULTS

The CYP2J2 (-76G>T) rs890293 TT genotype in patients with early AMD was statistically significantly less frequent than in the control group: 0% vs. 2.5% (P=0.028). There were no significant differences in rs890293 gene polymorphisms between the exudative AMD and control groups. Also, the CYP2J2 (-76G>T) rs890293 TT genotype was statistically significantly less frequent in older early AMD patients (≥65 years) compared to control group persons (≥65 years): 0% vs. 5.4% (P=0.03).

CONCLUSION

The CYP2J2 (-76G>T) TT genotype may be associated with reduced manifestation of early stage AMD; therefore, a larger sample size is required for further analysis.

Is There A Role for Abscisic Acid, A Proven Anti-Inflammatory Agent, in the Treatment of Ischemic Retinopathies?

Ischemic retinopathies (IRs) are the main cause of severe visual impairment and sight loss, and are characterized by loss of blood vessels, accompanied by hypoxia, and neovascularization. Actual therapies, based on anti-vascular endothelial growth factor (VEGF) strategies, antioxidants or anti-inflammatory therapies are only partially effective or show some adverse side effects. Abscisic acid (ABA) is a phytohormone present in vegetables and fruits that can be naturally supplied by the dietary intake and has been previously studied for its benefits to human health. It has been demonstrated that ABA plays a key role in glucose metabolism, inflammation, memory and tumor growth. This review focuses on a novel and promising role of ABA as a potential modulator of angiogenesis, oxidative status and inflammatory processes in the retina, which are the most predominant characteristics of the IRs. Thus, this nutraceutical compound might shed some light in new therapeutic strategies focused in the prevention or amelioration of IRs-derived pathologies.

The Clinical Significance and Potential Role of C-Reactive Protein in Chronic Inflammatory and Neurodegenerative Diseases

C-reactive protein (CRP) is an acute-phase protein synthesized by hepatocytes in response to pro-inflammatory cytokines during inflammatory/infectious processes. CRP exists in conformationally distinct forms such as the native pentameric CRP and monomeric CRP (mCRP) and may bind to distinct receptors and lipid rafts and exhibit different functional properties. It is known as a biomarker of acute inflammation, but many large-scale prospective studies demonstrate that CRP is also known to be associated with chronic inflammation. This review is focused on discussing the clinical significance of CRP in chronic inflammatory and neurodegenerative diseases, such as cardiovascular disease, type 2 diabetes mellitus, age-related macular degeneration, hemorrhagic stroke, Alzheimer’s disease, and Parkinson’s disease, including recent advances on the implication of CRP and its forms specifically on the pathogenesis of these diseases. Overall, we highlight the advances in these areas that may be translated into promising measures for the diagnosis and treatment of inflammatory diseases.

The Association of Serum Iron-Binding Proteins and the Antioxidant Parameter Levels in Age-Related Macular Degeneration

PURPOSE

Age-related macular degeneration (AMD) is the leading cause of the irreversible central visual loss among the elderly in the developed countries. Iron is considered a potent generator of the oxidative damage whose levels increase with age, potentially exacerbating the age-related diseases. The aim of this study was to assess the serum values of iron, and iron-binding proteins (transferrin, ferritin, and haptoglobin) in patients with AMD along with the parameters of the antioxidant defense: superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase, and total antioxidant status (TAS), in order to analyze the possible impact of iron and iron-binding proteins to the development of oxidative stress in AMD patients, and the association of the selected parameters with the AMD. In addition, the aim was to examine the gender differences and calculate the cutoff points of tested parameters that could be associated with AMD.

MATERIAL AND METHODS

A cross-sectional study included 55 AMD patients aged 71.7 ± 7.36 years and 65 aged-matched control subjects aged 70.25 ± 6.46 years.

RESULTS

Significantly lower ferritin (P = 0.025), SOD (P = 0.026), GPx (P = 0.019), and TAS (P < 0.004) values were found in patients with AMD compared to the controls (P < 0.05). Significant association of GPx < 27 U/gHb (odds ratio [OR]: 1.13; 95% confidence interval [CI] 0.78-2.10; P = 0.049), TAS < 1.25 mmol/L (OR: 5.77; 95% CI 0.98-367.0; P < 0.000), ferritin < 84.8 pg/mL (OR: 2.52; 95% CI 1.37-4.62; P = 0.002), and haptoglobin<1.51 g/L (OR: 1.94; 95% CI 1.05-3.56; P = 0.031) was found with the AMD. According to receiver operating characteristic curve analysis, ferritin concentration <84.8 pg/L, GPx < 27 U/gHb, and TAS < 1.25 mmol/L have sufficient predictive ability for AMD.

CONCLUSION

Significantly reduced capacity of the antioxidant defense system and iron-binding storage proteins (ferritin) found in AMD could have an important role in the development of increase oxidative stress in AMD patients.