Assessing gender differences in food preferences and physical activity: a population-based survey

Introduction

Food preferences are influenced by various factors, such as culture, age, and gender. The relationship between food tastes, meal preferences, and eating habits has been studied extensively in recent years; however, research on gender differences in these fields still needs to be addressed. The aim of this study was to investigate gender differences in food preferences and eating habits through self-administered questionnaires in a large Italian population sample.

Methods

The online survey included questions on food tastes, meal preferences, eating habits, and sport involvement.

Results

The results of the study underline significant gender-specific dietary tendencies among the 2198 participants (1314 females and 884 males, average age 41.1 ± 12.7 yrs). The majority of subjects were in the annual income range between €20,000 and €40,000. Our analysis reveals significant gender differences in dietary preferences and eating habits. Men prefer red and processed meat, with significantly higher consumption rates than women. Women, on the other hand, show a greater inclination towards vegetables, whole grains, tofu, and high-cocoa-content dark chocolate, aligning with healthier food choices. The study also found differences in eating behaviors, including the frequency of meals, snacking habits, and hunger patterns: women tend to eat more frequently and report higher levels of hunger in the morning, while men tend to skip snacks. Furthermore, differences extend to eating contexts, such as the speed of eating, eating out, and eating alone, with men more likely to eat quickly and dine out. Episodes of uncontrolled eating without hunger also differ, with women reporting these behaviors more frequently than men. In addition, the analysis of sports preferences showed distinct patterns, with a lower percentage of women playing sports and those who do play sports preferring endurance and strength training, while men prefer strength training and endurance sports.

Discussion

These findings elucidate the complex interplay of biological, cultural, and gender-based factors in shaping dietary preferences and eating behaviors. In particular, our study reveals that gender dynamics significantly influence food choice and eating habits: women tend to choose healthier foods and eat regular meals, while men show preferences for specific tastes and meal-related behaviors. This analysis underscores the nuanced differences between male and female dietary patterns, influenced not only by inherent biological factors such as genetics and hormonal responses but also by societal norms and cultural contexts. Taken together, our results highlight the importance of integrating different perspectives, thus providing valuable insights into the development of public health strategies and tailored nutrition interventions aimed at chronic disease prevention.

Effects of Different Nutritional Patterns and Physical Activity on Body Composition: A Gender and Age Group Comparative Study

This cross-sectional study analyses differences in dietary habits, taste preferences, variety of protein sources and body composition (BC) profiles among individuals following omnivorous, flexitarian, lacto-ovo-vegetarian and pescatarian diets. Furthermore, it assesses the correlations between these dietary patterns and various sports, classified by exercise intensity, in relation to BC parameters. The study analysed the eating habits and BC data of 1342 participants aged 18-65 years, classified into four diet groups based on their 7-day food diaries and questionnaire responses. Our analysis revealed gender- and age-related differences in weekly food consumption and protein source variety, with men generally consuming more meat, processed meat and fish than women, especially in younger age groups. Differences in dairy and soy consumption were also noted between age groups, while legume and soy preferences showed no gender disparity across all ages. Among non-sporting individuals, vegetarians exhibited lower fat mass (FM%) compared to other diets, while among athletes, vegetarians and pescatarians in in endurance and strength sports, respectively, displayed lower FM%, with flexitarians and omnivores in endurance sports showing higher FM%. Non-athletic omnivores and vegetarians demonstrated a greater proportion of body protein, while among athletes, those engaged in strength training exhibited a higher body protein content across all dietary groups compared to those in endurance training. Among non-athletic groups, vegetarians exhibited the lowest FM/FFM (fat mass/fat-free mass) ratio, while among athletes, vegetarians in endurance sports and participants in strength training across other diets showed lower FM/FFM ratios. The results emphasise the complex interaction between diet, BC and lifestyle choices, revealing how different combinations of diet and sport are associated with optimised BC.

The Impact of Diet and Physical Activity on Fat-to-Lean Mass Ratio

In this retrospective study, we evaluated the efficacy of a personalised low-calorie Mediterranean Diet (MD) in promoting fat mass (FM) reduction while preserving fat-free mass (FFM). This study involved 100 Caucasian adults aged 18-65 years who followed a tailored low-calorie MD for two months. The total energy expenditure was assessed using a multi-sensor armband. The change in body composition (BC) was evaluated using the Δ% FM-to-FFM ratio, calculated as the difference in the FM to FFM ratio before and after the diet, divided by the ratio before the diet, and multiplied by 100. A negative value indicates a greater decrease in FM than FFM, while a positive value suggests a greater increase in FM than FFM. This study demonstrated a significant FM reduction, with an average decrease of 5% (p < 0.001). However, the relationship between caloric reduction and the Δ% FM-to-FFM ratio showed a weak negative correlation (r = -0.03, p > 0.05). This suggests that the calorie deficit had a minimal direct impact on the BC changes. Subjects over the age of 30 showed an increase in muscle mass, while younger subjects showed no significant changes. Moreover, a direct correlation was observed between the changes in MET (Metabolic Equivalent of Task) values and the Δ% FM-to-FFM ratio, indicating that improved average physical activity intensity positively influences BC. In the female subgroup, high protein intake, exercise intensity, and the duration of physical activity were positively correlated with an improvement in the Δ% FM-to-FFM ratio. However, for individuals with BMI 20-25 kg/m2, high fibre intake was surprisingly negatively correlated with the Δ% FM-to-FFM ratio. This study underscores the intricate interplay between calorie restriction, physical activity intensity, and BC changes. It also suggests that individual factors, including age, gender, and BMI, may influence the response to a low-calorie MD. However, further prospective studies with larger sample sizes are necessary to confirm and expand upon these findings.

Very-low-calorie ketogenic diet vs hypocaloric balanced diet in the prevention of high-frequency episodic migraine: the EMIKETO randomized, controlled trial

BACKGROUND

Migraine is the second world's cause of disability. Among non-pharmacological treatments, nutritional intervention, particularly ketogenic diet, represents one of the most promising approaches.

METHODS

This a prospective, single center, randomized, controlled study aimed at evaluating the efficacy of a very low-calorie ketogenic diet (VLCKD) compared to a hypocaloric balanced diet (HBD) in migraine prophylaxis in patients affected by high-frequency episodic migraine (HFEM) with a Body Mass Index (BMI) > 27 kg/m2. Fifty-seven patients were randomly assigned to a VLCKD (group 1) or HBD (group 2). Group 1 patients followed a VLCKD for 8 weeks, followed by a low calorie diet (LCD, weeks 9-12), and a HBD (weeks 13-24), whereas group 2 patients followed a HBD from week 0 to 24. Anthropometric indexes, urine and blood chemistry were assessed at enrollment, baseline, weeks 4, 8, 12, and 24. Migraine characteristics were evaluated at baseline, weeks 8, 12 and 24. Change in monthly migraine days (MMDs) at weeks 5-8 compared to baseline was the primary endpoint. Secondary endpoints encompassed changes in visual analogue scale (VAS), Headache Impact Test-6 (HIT-6) and Short Form Health Survey-36 (SF-36) scores. We also studied effects on circulating lymphocytes and markers of inflammation, changes in plasma aldosterone and renin levels before and after VLCKD or HBD treatment.

RESULTS

Reduction from baseline in MMDs was greater in VLCKD compared to HBD group at week 8 (p = 0.008), at week 12 (p = 0.007), when ketosis had been interrupted by carbohydrates reintroduction, and at week 24 (p = 0.042), when all patients were following the same dietary regimen. Quality of life scores (SF-36) were improved in VLCKD group at week 8 and 12, and were also improved in HBD group, but only at week 12. Weight-loss was significantly higher in VLCKD group at week 8 (p = 0.002) and week 12 (p = 0.020). At the end of the study weight loss was maintained in VLCKD group whereas a slight weight regain was observed in HBD group. Inflammatory indexes, namely C reactive protein (CRP), neutrophil to lymphocyte ratio (NLR) and total white blood cell count (WBC) were significantly reduced (p < 0.05) in VLCKD group at week 12. Aldosterone plasma level were significantly increased in both groups at week 8, particularly in VLCKD group. However, electrolytes and renin plasma levels were never altered throughout the study in both groups.

CONCLUSIONS

VLCKD is more effective than HBD in reducing MMD in patients with HFEM and represents an effective prophylaxis in patients with overweight/obesity. Trial registration ClinicalTrials.gov identifier: NCT04360148.

Ketogenic Diet as a Possible Non-pharmacological Therapy in Main Endocrine Diseases of the Female Reproductive System: A Practical Guide for Nutritionists

PURPOSEOF REVIEW

This narrative review explored the role of ketogenic diets (KDs) in improving fertility outcomes, low-grade inflammation, body weight, visceral adipose tissue, and its potential use in certain types of cancer, through its favorable actions on mitochondrial function, reactive oxygen species generation, chronic inflammation, and tumor growth inhibition. RECENT FINDINGS  : Nutrition is crucial to maintain the female reproductive system's health. Evidence on the association between diet and female reproductive system has greatly expanded over the last decade, leading to the identification of specific diet therapy, particularly KDs. KDs has been proved to be an effective weight-loss tool. To date, KDs is being increasingly used in the treatment of many diseases, such as obesity, type 2 diabetes mellitus. KDs is a dietary intervention capable of ameliorating the inflammatory state and oxidative stress through several mechanisms. Due to the increasing use of KDs beyond obesity, this literature review will provide the latest scientific evidence of its possible use in common disorders of the female endocrine-reproductive tract, and a practical guide to its use in these patients.

Sustainable Strategies for Increasing Legume Consumption: Culinary and Educational Approaches

Legumes are nutrient-dense crops with health-promoting benefits. However, several barriers are associated with their consumption. Emerging issues including food neophobic tendencies or taboos, unclear dietary guidelines on legume consumption, health concerns, and socio-economic reasons, as well as long cooking procedures, adversely affect legume consumption frequency. Pre-treatment methods, including soaking, sprouting, and pulse electric field technology, are effective in reducing the alpha-oligosaccharides and other anti-nutritional factors, eventually lowering cooking time for legumes. Extrusion technology used for innovative development of legume-enriched products, including snacks, breakfast cereals and puffs, baking and pasta, represents a strategic way to promote legume consumption. Culinary skills such as legume salads, legume sprouts, stews, soups, hummus, and the development of homemade cake recipes using legume flour could represent effective ways to promote legume consumption. This review aims to highlight the nutritional and health effects associated with legume consumption, and strategies to improve their digestibility and nutritional profile. Additionally, proper educational and culinary approaches aimed to improve legumes intake are discussed.

Neutral Effect of Skeletal Muscle Mineralocorticoid Receptor on Glucose Metabolism in Mice

The mineralocorticoid receptor (MR) is able to regulate the transcription of a number of genes in the myotube, although its roles in skeletal muscle (SM) metabolism still await demonstration. SM represents a major site for glucose uptake, and its metabolic derangements play a pivotal role in the development of insulin resistance (IR). The aim of this study was to investigate the contribution of SM MR in mediating derangements of glucose metabolism in a mouse model of diet-induced obesity. We observed that mice fed a high-fat diet (HFD mice) showed impaired glucose tolerance compared to mice fed a normal diet (ND mice). Mice fed a 60% HFD treated with the MR antagonist Spironolactone (HFD + Spiro) for 12 weeks revealed an improvement in glucose tolerance, as measured with an intraperitoneal glucose tolerance test, compared with HFD mice. To investigate if blockade of SM MR could contribute to the favorable metabolic effects observed with pharmacological MR antagonism, we analyzed MR expression in the gastrocnemius, showing that SM MR protein abundance is downregulated by HFD compared to ND mice and that pharmacological treatment with Spiro was able to partially revert this effect in HFD + Spiro mice. Differently from what we have observed in adipose tissue, where HDF increased adipocyte MR expression, SM MR protein was down-regulated in our experimental model, suggesting a completely different role of SM MR in the regulation of glucose metabolism. To confirm this hypothesis, we investigated the effects of MR blockade on insulin signaling in a cellular model of IRin C2C12 myocytes, which were treated with or without Spiro. We confirmed MR protein downregulation in insulin-resistant myotubes. We also analyzed Akt phosphorylation upon insulin stimulation, and we did not observe any difference between palmitate- and palmitate + Spiro-treated cells. These results were confirmed by in vitro glucose uptake analysis. Taken together, our data indicate that reduced activity of SM MR does not improve insulin signaling in mouse skeletal myocytes and does not contribute to the favorable metabolic effects on glucose tolerance and IR induced by systemic pharmacological MR blockade.

Health Effects of Red Wine Consumption: A Narrative Review of an Issue That Still Deserves Debate

A strong controversy persists regarding the effect of red wine (RW) consumption and health. Guidelines for the prevention of cardiovascular diseases (CVD) and cancers discourage alcohol consumption in any form, but several studies have demonstrated that low RW intake may have positive effects on CVD risk. This review evaluated randomised controlled trials (RCTs), examining the recent literature on the correlations between acute and chronic RW consumption and health. All RCTs published in English on PubMed from 1 January 2000 to 28 February 2023 were evaluated. Ninety-one RCTs were included in this review, seven of which had a duration of more than six months. We assessed the effect of RW on: (1) antioxidant status, (2) cardiovascular function, (3) coagulation pathway and platelet function, (4) endothelial function and arterial stiffness, (5) hypertension, (6) immune function and inflammation status, (7) lipid profile and homocysteine levels, (8) body composition, type 2 diabetes and glucose metabolism, and (9) gut microbiota and the gastrointestinal tract. RW consumption mostly results in improvements in antioxidant status, thrombosis and inflammation markers, lipid profile, and gut microbiota, with conflicting results on hypertension and cardiac function. Notably, beneficial effects were observed on oxidative stress, inflammation, and nephropathy markers, with a modest decrease in CVD risk in five out of seven studies that evaluated the effect of RW consumption. These studies were conducted mainly in patients with type 2 diabetes mellitus, and had a duration between six months and two years. Additional long-term RCTs are needed to confirm these benefits, and assess the potential risks associated with RW consumption.

Nutraceuticals in Brown Adipose Tissue Activation

Obesity and its associated comorbidities have become pandemic, and challenge the global healthcare system. Lifestyle changes, nutritional interventions and phamaceuticals should be differently combined in a personalized strategy to tackle such a public health burden. Altered brown adipose tissue (BAT) function contributes to the pathophysiology of obesity and glucose metabolism dysfunctions. BAT thermogenic activity burns glucose and fatty acids to produce heat through uncoupled respiration, and can dissipate the excessive calorie intake, reduce glycemia and circulate fatty acids released from white adipose tissue. Thus, BAT activity is expected to contribute to whole body energy homeostasis and protect against obesity, diabetes and alterations in lipid profile. To date, pharmacological therapies aimed at activating brown fat have failed in clinical trials, due to cardiovascular side effects or scarce efficacy. On the other hand, several studies have identified plant-derived chemical compounds capable of stimulating BAT thermogenesis in animal models, suggesting the translational applications of dietary supplements to fight adipose tissue dysfunctions. This review describes several nutraceuticals with thermogenic properties and provides indications, at a molecular level, of the regulation of the adipocyte thermogenesis by the mentioned phytochemicals.

RF24 | PSUN109 Very Low Calorie Ketogenic Diet combined with interval training for preserving muscle mass during weight loss in sarcopenic obesity: a pilot study

Background

The prevalence of sarcopenic obesity (SO) is increasing worldwide, posing important challenges to public health and national health care system, especially during the COVID pandemic. In subjects with SO, it is essential to reduce body weight preserving lean mass, in order to avoid a worsening of muscle function. Lifestyle modification with adequate nutrition and proper physical activity is essential to counteract SO progression. In accordance with the Position Statement of the Italian Society of Endocrinology, Very Low Calorie Ketogenic Diet (VLCKD), a well established nutritional intervention in the context of obesity, has been promoted also for the treatment of SO (1). To date, the effects of physical training during VLCKD have not been studied.

Aim

This pilot study aims to determine the efficacy of VLCKD combined with interval training, compared to a VLCKD alone, on weight-loss, body composition and physical performance in patient with SO.

Materials and methods

Twenty-six patients with SO, aged between 50 and 70 years, who met the inclusion criteria, accepted to adhere to a VLCKD nutritional program (< 800 Kcal/die) and gave informed consent, were enrolled in the study. Thirteen patients followed a structured VLCKD protocol (VLCKD group) and thirteen patients followed a structured VLCKD protocol combined with interval training (IT), two times a week (VLCKD+IT group). Data were collected at baseline (T0) and after 45 days (T45). Anthropometric indexes, body composition analysis by Bioelectrical Impedance Analysis (BIA), muscle strength measurement by Chair Stand Test and physical performance analysis by Short Physical Performance Battery were assessed at baseline and at the end of treatment.

Results

At the end of the study, Body Mass Index, body weight and waist circumference were significantly reduced both in the VLCKD group and in the VLCKD+IT group. Moreover, significant improvement of muscle strength and physical performance was found in all groups. A significant reduction in hip circumference was observed only in the VLCKD+IT group. A multiple comparison of delta variations in the measured parameters between groups was performed. No differences were observed for the majority of parameters, with the exception of FFM and FM: interestingly, the individuals fed with VLCKD combined with IT preserved their FFM (p <0.0001) and reduced their FM (p = 0.0006) to a greater extent than in the VLCKD group.

Conclusions

Our pilot study showed that VLCKD was effective in terms of body weight reduction, particularly of FM; moreover, we conclude that the combination of VLCKD and interval training determines a better preservation of FFM. References: 1. Caprio, M. et al. Very-low-calorie ketogenic diet (VLCKD) in the management of metabolic diseases: systematic review and consensus statement from the Italian Society of Endocrinology (SIE). J Endocrinol Invest 2019, 42, 1365-1386, doi: 10.1007/s40618-019-01061-2.

Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m., Sunday, June 12, 2022 12:48 p.m. - 12:53 p.m.

Very low calorie ketogenic diet combined with physical interval training for preserving muscle mass during weight loss in sarcopenic obesity: A pilot study

Background

The prevalence of sarcopenic obesity (SO) is increasing worldwide, posing important challenges to public health and national health care system, especially during the COVID pandemic. In subjects with SO, it is essential to reduce body weight, and to preserve lean mass, to avoid worsening of muscle function. Adequate nutrition and correct physical activity is essential to counteract SO progression. Very Low Calorie Ketogenic Diet (VLCKD), a well-established nutritional intervention for obesity, has been also indicated for the treatment of SO. To date, the effects of physical training during VLCKD have not been investigated.

Aim

This pilot study aims to determine the efficacy of VLCKD combined with interval training, compared to a VLCKD alone, on weight-loss, body composition, and physical performance in participants with SO.

Materials and methods

Twenty-four participants with SO, aged between 50 and 70 years, who met the inclusion criteria, accepted to adhere to a VLCKD (<800 Kcal/die) and to give informed consent, were enrolled in the study. Twelve participants followed a structured VLCKD protocol (VLCKD group) and twelve followed the same VLCKD protocol combined with interval training (IT), twice per week (VLCKD + IT group). Data were collected at baseline (T0) and after 6-week of treatment (T6). Anthropometric indexes, body composition analysis by Bioelectrical Impedance Analysis (BIA), muscle strength and physical performance analysis were assessed at baseline and at the end of treatment.

Results

At the end of the study, body mass index (BMI), body weight, waist circumference, and hip circumference were significantly reduced in both VLCKD group and VLCKD + IT group. Interestingly, a significant improvement in muscle strength and physical performance was observed in both groups. A multiple comparison of delta variations in all parameters between groups was performed. No differences were observed for the majority of anthropometric and biochemical parameters, with the exception of fat free mass (FFM) and fat mass (FM): notably, participants who followed a VLCKD combined with IT preserved FFM (p < 0.001) and reduced FM (p = 0.001) to a greater extent than what observed in VLCKD group. Moreover, high density lipoprotein (HDL) cholesterol plasma levels were significantly higher in the VLCKD + IT group compared to the VLCKD group.

Conclusion

This pilot study confirms that VLCKD is effective in terms of body weight reduction, particularly FM; moreover, the combination of VLCKD and interval training could determine a better preservation of FFM.

BNT162b2 mRNA COVID-19 Vaccine Does Not Impact the Honeymoon Phase in Type 1 Diabetes: A Case Report

Type 1 diabetes (T1D), which is caused by the autoimmune destruction of insulin-secreting pancreatic beta cells, represents a high-risk category requiring COVID-19 vaccine prioritization. Although COVID-19 vaccination can lead to transient hyperglycemia (vaccination-induced hyperglycemia; ViHG), its influence on the course of the clinical remission phase of T1D (a.k.a. “honeymoon phase”) is currently unknown. Recently, there has been an increasing concern that COVID-19 vaccination may trigger autoimmune phenomena. We describe the case of a 24-year-old young Italian man with T1D who received two doses of the BNT162b2 mRNA (Pfizer-BioNTech) COVID-19 vaccine during a prolonged honeymoon phase. He experienced a transient impairment in glucose control (as evidenced by continuous glucose monitoring) that was not associated with substantial changes in stimulated C-peptide levels and islet autoantibody titers. Nonetheless, large prospective studies are needed to confirm the safety and the immunometabolic impact of the BNT162b2 vaccine in T1D patients during the honeymoon phase. Thus far, T1D patients who are going to receive COVID-19 vaccination should be warned about the possible occurrence of transient ViHG and should undergo strict postvaccination surveillance.

Influence of Nutritional Status and Physical Exercise on Immune Response in Metabolic Syndrome

Metabolic Syndrome (MetS) is a cluster of metabolic alterations mostly related to visceral adiposity, which in turn promotes glucose intolerance and a chronic systemic inflammatory state, characterized by immune cell infiltration. Such immune system activation increases the risk of severe disease subsequent to viral infections. Strong correlations between elevated body mass index (BMI), type-2-diabetes and increased risk of hospitalization after pandemic influenza H1N1 infection have been described. Similarly, a correlation between elevated blood glucose level and SARS-CoV-2 infection severity and mortality has been described, indicating MetS as an important predictor of clinical outcomes in patients with COVID-19. Adipose secretome, including two of the most abundant and well-studied adipokines, leptin and interleukin-6, is involved in the regulation of energy metabolism and obesity-related low-grade inflammation. Similarly, skeletal muscle hormones—called myokines—released in response to physical exercise affect both metabolic homeostasis and immune system function. Of note, several circulating hormones originate from both adipose tissue and skeletal muscle and display different functions, depending on the metabolic context. This review aims to summarize recent data in the field of exercise immunology, investigating the acute and chronic effects of exercise on myokines release and immune system function.

Could very low-calorie ketogenic diets turn off low grade inflammation in obesity? Emerging evidence

Obesity is an emerging non-communicable disease associated with chronic low-grade inflammation and oxidative stress, compounded by the development of many obesity-related diseases, such as cardiovascular disease, type 2 diabetes mellitus, and a range of cancers. Originally developed for the treatment of epilepsy in drug non-responder children, the ketogenic diet (KD) is being increasingly used in the treatment of many diseases, including obesity and obesity-related conditions. The KD is a dietary pattern characterized by high fat intake, moderate to low protein consumption, and very low carbohydrate intake (<50 g) that has proved to be an effective and weight-loss tool. In addition, it also appears to be a dietary intervention capable of improving the inflammatory state and oxidative stress in individuals with obesity by means of several mechanisms. The main activity of the KD has been linked to improving mitochondrial function and decreasing oxidative stress. β-hydroxybutyrate, the most studied ketone body, has been shown to reduce the production of reactive oxygen species, improving mitochondrial respiration. In addition, KDs exert anti-inflammatory activity through several mechanisms, e.g., by inhibiting activation of the nuclear factor kappa-light-chain-enhancer of activated B cells, and the inflammatory nucleotide-binding, leucine-rich-containing family, pyrin domain-containing-3, and inhibiting histone deacetylases. Given the rising interest in the topic, this review looks at the underlying anti-inflammatory and antioxidant mechanisms of KDs and their possible recruitment in the treatment of obesity and obesity-related disorders.

VLCKD in Combination with Physical Exercise Preserves Skeletal Muscle Mass in Sarcopenic Obesity after Severe COVID-19 Disease: A Case Report

The prevalence of sarcopenic obesity is increasing worldwide, with a strong impact on public health and the national health care system. Sarcopenic obesity consists of fat depot expansion and associated systemic low-grade inflammation, exacerbating the decline in skeletal muscle mass and strength. Dietary approach and physical exercise represent essential tools for reducing body weight and preserving muscle mass and function in subjects with sarcopenic obesity. This case report describes the effects of a dietary intervention, based on a Very-Low-Calorie Ketogenic Diet (VLCKD) combined with physical exercise, on body composition, cardiometabolic risk factors, and muscle strength in a woman with sarcopenic obesity, two weeks after hospitalization for bilateral interstitial pneumonia due to COVID-19. To our knowledge, this is the first case report to describe the efficacy of a combined approach intervention including VLCKD along with physical exercise, in reducing fat mass, improving metabolic profile, and preserving skeletal muscle performance in a patient with obesity, soon after severe COVID-19 disease.

Class-specific responses of brown adipose tissue to steroidal and nonsteroidal mineralocorticoid receptor antagonists

Aldosterone exerts deleterious effects on the cardiovascular system and promotes adipose tissue expansion via mineralocorticoid receptor (MR) activation. We previously demonstrated that administration of steroidal mineralocorticoid receptor antagonists (MRA) in mice fed a moderate high-fat diet is able to reduce white adipose tissue (WAT) expansion, stimulate browning of WAT and activate interscapular brown adipose tissue (iBAT). Here, we aimed to compare the metabolic and adipose tissue-specific effects of the novel non-steroidal MRA finerenone (Fine) and spironolactone (Spiro) in a mouse model of very high-fat diet (HFD)-induced obesity. C57BL/6 J male mice were fed a 60% HFD containing or not Spiro or Fine for 12 weeks. WAT and iBAT morphology and adipose tissue gene expression analysis were assessed. After 12 weeks, both groups of mice showed similar weight gain compared to the HFD group. Histological and molecular analyses of WAT did not show significant differences among all experimental groups; differently, iBAT histological analysis revealed that Fine was able to increase recruitment of brown adipocytes in this depot, whereas mice treated with Spiro failed to elicit any iBAT response, as indicated by no changes in lipid droplets size and iBAT density, compared to HFD. Increased iBAT recruitment could explain, at least in part, the improved insulin resistance observed in mice treated with Fine, as shown by a significant reduction in homeostasis model assessment of insulin resistance (HOMA) index. These findings were confirmed by gene expression analysis of ucp-1, pgc1-α, and beta-3 adrenoreceptor (Adrb3) in iBAT, revealing significantly higher expression of these thermogenic genes in HFD + Fine group compared to HFD, whereas Spiro did not modify their expression. In summary, we demonstrated that, differently from Fine, Spiro did not induce iBAT recruitment. Our current study suggests that Fine, through its direct effects on iBAT, represents a promising pharmacologic tool to treat human metabolic diseases associated with adipose tissue dysfunctions.

Ritmi circadiani e variabili metaboliche

I ritmi circadiani sono influenzati da numerose variabili correlate allo stile di vita, soprattutto in relazione ai ritmi imposti dalla società moderna, e vengono profondamente alterati da diverse condizioni patologiche. La fisiologia circadiana è organizzata in modo complesso e integrato; molti dei fattori che sincronizzano il sistema sono a loro volta influenzati e regolati da diversi assi ormonali. Parallelamente, i disturbi del ritmo circadiano derivano da input non ottimali dei fattori sincronizzanti o da condizioni patologiche, e le conseguenze determinano un impatto significativo in diverse condizioni, quali l’obesità e i disturbi del sonno. Durante l’attuale emergenza COVID-19 sono stati registrati crescenti tassi di alterazioni del sonno, complici la preoccupazione diffusa, un comportamento alimentare alterato e la difficoltà per molti, durante il lockdown, nel mantenere ritmi di vita regolari (Barrea et al. in J Transl Med 18:1–11, 2020). Le misure di intervento che si sono mostrate più promettenti contro la desincronizzazione circadiana sono quelle che agiscono sullo stile di vita, basate sul recupero di un corretto ritmo del sonno, la corretta esposizione alla luce solare, l’idonea distribuzione dei pasti e del timing alimentare e lo svolgimento di un’adeguata attività fisica.

Nonsteroidal mineralcorticoid receptor antagonists: Novel therapeutic implication in the management of patients with type 2 diabetes

Growing evidencehas described a correlation between aldosterone, obesity, and insulin resistance, suggesting that adipocyte-related factors and mineralocorticoid receptor (MR) overactivation may alter aldosterone secretion, potentially leading to obesity and glucose intolerance. Preclinical studies showed that pharmacological antagonism of MR prevents white adipose tissue dysfunction(s) and expansion, activates brown adipose tissue, and improves glucose tolerance. The clinical use of nonsteroidal MR antagonists has been shown to reduce the risk of diabetic kidney disease progression and cardiovascular events in patients with diabetes. This review aims to summarize the effects of pharmacological MR blockade on obesity and its associated metabolic comorbidities, with a particular focus on the therapeutic implications of nonsteroidal MR antagonists in the management of patients with diabetes.

Exploring the Role of Skeletal Muscle in Insulin Resistance: Lessons from Cultured Cells to Animal Models

Skeletal muscle is essential to maintain vital functions such as movement, breathing, and thermogenesis, and it is now recognized as an endocrine organ. Muscles release factors named myokines, which can regulate several physiological processes. Moreover, skeletal muscle is particularly important in maintaining body homeostasis, since it is responsible for more than 75% of all insulin-mediated glucose disposal. Alterations of skeletal muscle differentiation and function, with subsequent dysfunctional expression and secretion of myokines, play a key role in the pathogenesis of obesity, type 2 diabetes, and other metabolic diseases, finally leading to cardiometabolic complications. Hence, a deeper understanding of the molecular mechanisms regulating skeletal muscle function related to energy metabolism is critical for novel strategies to treat and prevent insulin resistance and its cardiometabolic complications. This review will be focused on both cellular and animal models currently available for exploring skeletal muscle metabolism and endocrine function.

SIRT5 Inhibition Induces Brown Fat-Like Phenotype in 3T3-L1 Preadipocytes

Brown adipose tissue (BAT) activity plays a key role in regulating systemic energy. The activation of BAT results in increased energy expenditure, making this tissue an attractive pharmacological target for therapies against obesity and type 2 diabetes. Sirtuin 5 (SIRT5) affects BAT function by regulating adipogenic transcription factor expression and mitochondrial respiration. We analyzed the expression of SIRT5 in the different adipose depots of mice. We treated 3T3-L1 preadipocytes and mouse primary preadipocyte cultures with the SIRT5 inhibitor MC3482 and investigated the effects of this compound on adipose differentiation and function. The administration of MC3482 during the early stages of differentiation promoted the expression of brown adipocyte and mitochondrial biogenesis markers. Upon treatment with MC3482, 3T3-L1 adipocytes showed an increased activation of the AMP-activated protein kinase (AMPK), which is known to stimulate brown adipocyte differentiation. This effect was paralleled by an increase in autophagic/mitophagic flux and a reduction in lipid droplet size, mediated by a higher lipolytic rate. Of note, MC3482 increased the expression and the activity of adipose triglyceride lipase, without modulating hormone-sensitive lipase. Our findings reveal that SIRT5 inhibition stimulates brown adipogenesis in vitro, supporting this approach as a strategy to stimulate BAT and counteract obesity.

The novel non-steroidal MR antagonist finerenone improves metabolic parameters in high-fat diet-fed mice and activates brown adipose tissue via AMPK-ATGL pathway

Mineralocorticoid receptor antagonists (MRAs) are recommended for the treatment of heart failure and hypertension, mainly due to their natriuretic and anti-fibrotic mode of action. Rodent studies have shown that MRAs can prevent adverse metabolic consequences of obesity but an elucidation of underlying molecular mechanisms is missing. Here, we investigated metabolic effects of the novel non-steroidal MRA finerenone (FIN) in a mouse model of high-fat diet (HFD)-induced obesity and the signaling pathways activated by MR antagonism at level of interscapular brown adipose tissue (iBAT). C57BL/6J male mice were fed a normal diet or a HFD (with60% kcal from fat) containing or not FIN for 3 months. Metabolic parameters, adipose tissue morphology, gene and protein expression analysis were assessed. We also used brown adipocyte cultures (T37i cells) to investigate the effects of FIN-mediated MR antagonism upon lipid and mitochondrial metabolism. HFD + FIN-treated mice showed improved glucose tolerance together with increased multilocularity and higher expression of thermogenic markers at the level of iBAT, without differences in white adipose depots, suggesting an iBAT-specific effect of FIN. Mechanistically, FIN increased activation of AMP-activated protein kinase which, in turn, stimulated adipose triglyceride lipase activation, with subsequent increased expression of uncoupling protein-1 in brown adipocytes.

Neuroendocrine and Metabolic Effects of Low-Calorie and Non-Calorie Sweeteners

Since excessive sugar consumption has been related to the development of chronic metabolic diseases prevalent in the western world, the use of sweeteners has gradually increased worldwide over the last few years. Although low- and non-calorie sweeteners may represent a valuable tool to reduce calorie intake and prevent weight gain, studies investigating the safety and efficacy of these compounds in the short- and long-term period are scarce and controversial. Therefore, future studies will need to elucidate the potential beneficial and/or detrimental effects of different types of sweeteners on metabolic health (energy balance, appetite, body weight, cardiometabolic risk factors) in healthy subjects and patients with diabetes, obesity and metabolic syndrome. In this regard, the impact of different sweeteners on central nervous system, gut hormones and gut microbiota is important, given the strong implications that changes in such systems may have for human health. The aim of this narrative review is to summarize the current evidence for the neuroendocrine and metabolic effects of sweeteners, as well as their impact on gut microbiota. Finally, we briefly discuss the advantages of the use of sweeteners in the context of very-low calorie ketogenic diets.

SAT-LB106 Metabolic and Brown Adipose Tissue-Specific Effects of the Novel Non-Steroidal Mineralocorticoid Receptor Antagonist Finerenone in a Mouse Model of Diet-Induced Obesity

In this work we studied the metabolic effects of the novel non-steroidal MR antagonist Finerenone (FIN) in mice fed a high-fat diet (HFD, 60% kcal as fat). We also investigated the signaling pathways underlying the beneficial metabolic effects of MR antagonism. After 3 months of HFD, mice treated with FIN showed an improvement of glucose tolerance compared to control mice as shown by intraperitoneal glucose tolerance tests. Despite this metabolic improvement, FIN-treated mice did not show a reduction in body weight compared to control mice. In order to elucidate the favourable effect of FIN on glucose tolerance we performed histological and molecular analyses at level of different adipose depots. We did not observe significant differences in classical white adipose depots (subcutaneous and visceral) between control and FIN-treated mice. Interestingly, interscapular brown adipose tissue (iBAT) of FIN-treated mice showed an increased multilocularity and a reduced size of lipid droplets, suggesting an iBAT-specific effect of FIN. We than analyzed mRNA and protein expression of uncoupling protein 1 (UCP-1) and peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PCG1-alpha), showing a significant increase of both markers at iBAT level in FIN-treated mice. Furthermore, leptin and adenylate cyclase 5 (Adyc5) (specific white adipose tissue markers) mRNA expression was reduced at level of iBAT in FIN-treated mice. Finally, we demonstrated that FIN-induced MR antagonism determined an increased activation of AMP-activated protein kinase (AMPK) which, in turn, stimulated adipose triglyceride lipase (ATGL) activity, with subsequent up-regulation of genes involved in fatty acids oxidation, tricarboxylic acid cycle and thermogenesis, in iBAT. In summary, our study shows that FIN protects from iBAT dysfunction and improves glucose tolerance in HFD-fed mice. Importantly, FIN effects on iBAT are mediated by a MR-AMPK-ATGL-UCP-1 signaling cascade. Therefore, MR antagonism by FIN in clinical settings might offer metabolic advantages, on top of its anti-fibrotic action, in multi-morbid cardiorenal patients.

Mineralocorticoid Receptors in Metabolic Syndrome: From Physiology to Disease

Over the past decade, several studies have shown that activity of extra-renal mineralocorticoid receptors (MR) regulates vascular tone, adipogenesis, adipose tissue function, and cardiomyocyte contraction. In mice, abnormal activation of MR in the vasculature and in adipose tissue favors the occurrence of several components of the metabolic syndrome (MetS), such as hypertension, obesity, and glucose intolerance. Accordingly, high levels of aldosterone are associated with obesity and MetS in humans, suggesting that altered activation of aldosterone-MR system in extra-renal tissues leads to profound metabolic dysfunctions. In this context, in addition to the classical indications for heart failure and hypertension, MR antagonists (MRAs) nowadays represent a promising approach to tackle cardiovascular and metabolic disorders occurring in the MetS.

Minor role of mature adipocyte mineralocorticoid receptor in high-fat diet-induced obesity

Obesity is a major risk factor that contributes to the development of cardiovascular disease and type 2 diabetes. Mineralocorticoid receptor (MR) expression is increased in the adipose tissue of obese patients and several studies provide evidence that MR pharmacological antagonism improves glucose metabolism in genetic and diet-induced mouse models of obesity. In order to investigate whether the lack of adipocyte MR is sufficient to explain these beneficial metabolic effects, we generated a mouse model with inducible adipocyte-specific deletion of Nr3c2 gene encoding MR (adipo-MRKO). We observed a significant, yet not complete, reduction of Nr3c2 transcript and MR protein expression in subcutaneous and visceral adipose depots of adipo-MRKO mice. Notably, only mature adipocyte fraction lacks MR, whereas the stromal vascular fraction maintains normal MR expression in our mouse model. Adipo-MRKO mice fed a 45% high-fat diet for 14 weeks did not show any significant difference in body weight and fat mass compared to control littermates. Glucose and insulin tolerance tests revealed that mature adipocyte MR deficiency did not improve insulin sensitivity in response to a metabolic homeostatic challenge. Accordingly, no significant changes were observed in gene expression profile of adipogenic and inflammatory markers in adipose tissue of adipo-MRKO mice. Moreover, pharmacological MR antagonism in mature primary murine adipocytes, which differentiated ex vivo from WT mice, did not display any effect on adipokine expression. Taken together, these data demonstrate that the depletion of MR in mature adipocytes displays a minor role in diet-induced obesity and metabolic dysfunctions.

Induction of Atherosclerotic Plaques Through Activation of Mineralocorticoid Receptors in Apolipoprotein E-deficient Mice

Atherosclerosis is due to a chronic inflammatory response affecting vascular endothelium and is promoted by several factors such as hypertension, dyslipidemia, and diabetes. To date, there is evidence to support a role for circulating aldosterone as a risk factor for the development of cardiovascular disease. Transgenic mouse models have been generated to study cellular and molecular processes leading to atherosclerosis. In this manuscript, we describe a protocol that takes advantage of continuous infusion of aldosterone in ApoE^-/- mice and generates atherosclerotic plaques in the aortic root after 4 weeks of treatment. We, therefore, illustrate a method for quantification and characterization of atherosclerotic lesions at the aortic root level. The added value of aldosterone infusion is represented by the generation of atherosclerotic lesions rich in lipid and inflammatory cells after 4 weeks of treatment. We describe in detail the staining procedures to quantify lipid and macrophage content within the plaque. Notably, in this protocol, we perform heart tissue-embedding in OCT in order to preserve the antigenicity of cardiac tissue and facilitate detectability of antigens of interest. Analysis of the plaque phenotype represents a valid approach to study the pathophysiology of atherosclerosis development and to identify novel pharmacological targets for the development of anti-atherogenic drugs.

A novel combined glucocorticoid-mineralocorticoid receptor selective modulator markedly prevents weight gain and fat mass expansion in mice fed a high-fat diet

BACKGROUND

We have previously shown that antagonism of the mineralocorticoid receptor (MR) results in a potent antiadipogenic activity, in vitro and in vivo. Excessive glucocorticoid exposure is associated with obesity and related disorders in humans and mice.

METHODS

In this study, responses to a novel combined glucocorticoid receptor (GR)/MR antagonist were investigated in a model of diet-induced obesity. Female 10-week-old C57BL/6J mice were fed with normal chow or a high-fat diet (HFD) for 9 weeks. Mice fed a HFD were concomitantly treated for 9 weeks with the GR antagonist mifepristone (80 mg kg(-1) per day) or the novel combined GR/MR antagonist CORT118335 (80 mg kg(-1) per day). Male, juvenile 6-week-old C57BL/6J mice fed HFD were treated with CORT118335 for 4 weeks.

RESULTS

Mice fed a HFD showed a significant increase in total body weight and white fat mass, with impaired glucose tolerance and increased fat infiltration in livers. Interestingly, only CORT118335 completely prevented the HFD-induced weight gain and white fat deposition, whereas mifepristone showed no effect on body weight and modestly increased subcutaneous fat mass. Importantly, food intake was not affected by either treatment, and CORT118335 dramatically increased PGC-1α protein expression in adipose tissue, without any effect on UCP1. Both CORT118335 and mifepristone produced metabolic benefit, improving glucose tolerance, increasing adiponectin plasma levels, decreasing leptin and reducing mean adipocyte size. When tested in vitro, CORT118335 markedly reduced 3T3-L1 differentiation and reversed MR-mediated pro-adipogenic effects of aldosterone; differently, GR-mediated effects of dexamethasone were not antagonized by CORT118335, suggesting that it mostly acts as an antagonist of MR in cultured preadipocytes.

CONCLUSIONS

Combined GR/MR pharmacological antagonism markedly reduced HFD-driven weight gain and fat mass expansion in mice through the increase in adipose PGC-1α, suggesting that both receptors represent strategic therapeutic targets to fight obesity. The effects of CORT118335 in adipocytes seem predominantly mediated by MR antagonism.

Abstract P071: Mineralocorticoid Receptor Overexpression in Adipose Tissue Leads to Metabolic Syndrome and Induction of Prostaglandin D2 Synthase PTGDS and lipocalin-2 NGAL

Objectives: Metabolic Syndrome (MetS) is a cluster of metabolic risk factors associated with a higher risk for cardiovascular events. Adipose tissue (AT) plays a central role in the obesity-related metabolic abnormalities and it’s known that Mineralocorticoid Receptor (MR) activation affects adipocyte differentiation and function. The purposes of this study were to evaluate the molecular and metabolic consequences of adipocyte-targeted increase in MR expression in mice.

Results: In our study we showed that MR expression is increased in visceral adipose tissue (VAT) in a preclinical mouse model of MetS. Thus, we generated a double transgenic mouse model with a conditional and inducible overexpression of MR in AT (Adipo-MORE), demonstrating that increased expression of MR in AT contributes to MetS development with multiple metabolic abnormalities, including visceral obesity (VAT mass, control-MR 5.0±0.6 adipo-MORE 10.4±1.8, p<0.05), insulin resistance (HOMA index, control-MR 8.9±0.8 adipo-MORE 14.5±2.2, p<0.05) as well as dyslipidemia (total cholesterol, mg/dL control-MR 86.0±6.0 adipo-MR 109±6, p<0.05). We also identified prostaglandin D2 synthase (PTGDS) as a novel mediator of adipogenic effects of MR activation in adipocytes. Since adipokines play pivotal roles in the regulation of insulin sensitivity in obesity, we also focused on the role of lipocalin-2 NGAL, recently identified in our laboratory as a target of aldosterone action in cardiovascular system, as new adipocyte MR target. It’s known that NGALKO mice fed a high fat diet are protected from obesity-induced cardiovascular dysfunctions. In our model we observed an increase of NGAL mRNA levels (3 fold increase, p<0.05) in VAT. Moreover, NGAL was induced (2-8 fold increase, p<0.05) in primary cultures of adipocytes differentiated ex vivo from adipo-MORE mice in presence of aldosterone stimulation compared to controls.

Conclusions: We demonstrated that PTGDS is a novel direct MR target in rodent adipocytes mediating adipogenic effects of MR activation. We also found that NGAL is induced in presence of MR overexpression in adipocytes in vivo and ex vivo. In consideration of our results, other analyses are necessary to better understand the role of NGAL as adipocyte MR target.

Adipocyte Mineralocorticoid Receptor Activation Leads to Metabolic Syndrome and Induction of Prostaglandin D2 Synthase

Metabolic syndrome is a major risk factor for the development of diabetes mellitus and cardiovascular diseases. Pharmacological antagonism of the mineralocorticoid receptor (MR), a ligand-activated transcription factor, limits metabolic syndrome in preclinical models, but mechanistic studies are lacking to delineate the role of MR activation in adipose tissue. In this study, we report that MR expression is increased in visceral adipose tissue in a preclinical mouse model of metabolic syndrome and in obese patients. In vivo conditional upregulation of MR in mouse adipocytes led to increased weight and fat mass, insulin resistance, and metabolic syndrome features without affecting blood pressure. We identified prostaglandin D2 synthase as a novel MR target gene in adipocytes and AT56, a specific inhibitor of prostaglandin D2 synthase enzymatic activity, blunted adipogenic aldosterone effects. Moreover, translational studies showed that expression of MR and prostaglandin D2 synthase is strongly correlated in adipose tissues from obese patients.

Mineralocorticoid receptor in adipocytes and macrophages: a promising target to fight metabolic syndrome

Aldosterone is the primary ligand for the mineralocorticoid receptor (MR) and has been considered long time a "renal" hormone, acting at this site as a key regulator of plasma volume, electrolyte homeostasis and blood pressure. A new exciting era of MR biology began with the identification of MR in different non-epithelial tissues such as brain, heart, vessels, macrophages/monocytes, and adipose tissue. The distribution of MR in such a wide range of tissues has suggested novel and unexpected roles for MR, for example in energy metabolism and inflammation. An increasing body of evidence suggests a detrimental effect of aldosterone excess on the development of metabolic alterations. Disturbances in glucose metabolism due to inappropriate activation of MR are frequently observed in patients with primary aldosteronism as well as in obese subjects. MR antagonists have beneficial effects on glucose tolerance and metabolic parameters in experimental animals, whereas their role in humans remains unclear. The aim of this review is to discuss the pathophysiology of MR activation in experimental models, particularly at the level of adipocytes and macrophages, to discuss novel and sometimes contrasting insights from emerging studies, and to highlight deficiencies in the field.

The metabolic modulator trimetazidine triggers autophagy and counteracts stress-induced atrophy in skeletal muscle myotubes

It has recently been demonstrated that trimetazidine (TMZ), an anti-ischemic antianginal agent, is also able to improve exercise performance in patients with peripheral arterial disease. TMZ is a metabolic modulator, and the mechanisms underlying its cytoprotective anti-ischemic activity could be ascribed, at least in cardiomyocytes, to optimization of metabolism. However, regarding the cytoprotection exerted by TMZ on skeletal muscle and allowing the improvement of exercise performance, no information is yet available. In the present study, we investigated in detail the protective effects of this drug on in vitro skeletal muscle models of atrophy. Experiments carried out with murine C2C12 myotubes treated with TMZ revealed that this drug could efficiently counteract the cytopathic effects induced by the proinflammatory cytokine tumor necrosis factor-α and by the withdrawal of growth factors. Indeed, TMZ significantly counteracted the reduction in myotube size induced by these treatments. TMZ also increased myosin heavy chain expression and induced hypertrophy in C2C12 myotubes, both effects strongly suggesting a role of TMZ in counteracting atrophy in vitro. In particular, we found that TMZ was able to activate the phosphoinositide 3-kinase-Akt-mammalian target of rapamycin 2 pathway and to reduce the stress-induced transcriptional upregulation of atrogin-1, muscle ring finger protein 1, and myostatin, all of which are key molecules involved in muscle wasting. Moreover, this is the first demonstration that TMZ induces autophagy, a key mechanism involved in muscle mass regulation. On the basis of these results, it can be hypothesized that the improvement in exercise performance previously observed in patients could be ascribed to a cytoprotective mechanism exerted by TMZ on skeletal muscle integrity.

Role of mineralocorticoid receptor and renin-angiotensin-aldosterone system in adipocyte dysfunction and obesity

The mineralocorticoid receptor (MR) classically mediates aldosterone effects on salt homeostasis and blood pressure regulation in epithelial target tissues. In recent years, functional MRs have been identified in non classical targets of aldosterone actions, in particular in adipose tissue, where they mediate the effects of aldosterone and glucocorticoids in the control of adipogenesis, adipose expansion and its pro-inflammatory capacity. In this context, inappropriate MR activation has been demonstrated to be a causal factor in several pathologic conditions such as vascular inflammation, endothelial dysfunction, insulin resistance and obesity. The aim of this review is to summarize the latest developments in this rapidly developing field, and will focus on the role of MR and renin-angiotensin-aldosterone system (RAAS) as potential leading characters in the early steps of adipocyte dysfunction and obesity. Indeed modulation of MR activity in adipose tissue has promise as a novel therapeutic approach to treat obesity and its related metabolic complications. This article is part of a Special Issue entitled 'CSR 2013'.

Lipid peroxidation and total antioxidant capacity in vitreous, aqueous humor, and blood samples from patients with diabetic retinopathy

PURPOSE

To evaluate levels of malondialdehyde and the total antioxidant capacity (TAC) in the blood, aqueous humor, and vitreous bodies of diabetic and nondiabetic patients. We also measured the blood energy charge potential (ECP).

METHODS

We examined 19 patients with type 2 diabetes mellitus and diabetic retinopathy. Ten were scheduled for cataract surgery and pars plana vitrectomy because of proliferative diabetic retinopathy (PDR). The other nine, with mild nonproliferative PDR (NPDR), and fourteen nondiabetic, age-matched subjects enrolled as a control group were scheduled for cataract surgery and vitrectomy because of epiretinal membranes. Blood, aqueous humor and vitreous body samples were collected at the time of surgery. Malondialdehyde concentrations and blood ECP were measured with high-performance liquid chromatography. The TAC of the samples was estimated with the oxygen radical absorbance capacity method.

RESULTS

The level of blood and vitreous malondialdehyde in the PDR group was significantly higher compared to controls and to NPDR patients. PDR patients also had lower levels of TAC at the vitreous body and aqueous humor level, but not at the blood level, compared to controls and with NPDR patients. In all diabetic patients, the blood ECP values were significantly lower, compared to control subjects.

CONCLUSIONS

Our data support the hypothesis that oxidative stress and the decrease of antioxidant defenses are associated with the progression of diabetic retinopathy to its proliferative form. Antioxidant supply may have the effect of correcting oxidative stress and inhibiting disease progression.