Protective Effect of Tomato-Oleoresin Supplementation on Oxidative Injury Recoveries Cardiac Function by Improving β-Adrenergic Response in a Diet-Obesity Induced Model

Effects of carnosine supplementation on markers for the pathophysiological development of metabolic dysfunction-associated steatotic liver disease in a diet-induced model

Consumption of diets high in sugar and fat is related to the development of Metabolic dysfunction-associated steatotic liver disease (MASLD). Carnosine (CAR) is a dipeptide with antioxidant and anti-inflammatory action and has been studied for treating diseases. This work aimed to evaluate the effects of CAR on diet-induced MASLD in rats. Male Wistar rats were distributed into 2 groups (17 weeks): normocaloric (Co, n = 12), and hypercaloric diet rich in lipids and simple carbohydrates (MASLD, n = 12). After, the animals were redistributed to begin the treatment with CAR (4 weeks): Co (n = 6), Co + CAR (n = 6), MASLD (n = 6), and MASLD + CAR (n = 6), administered intraperitoneally (250 mg/kg). Evaluations included nutritional, hormonal and metabolic parameters; hepatic steatosis, inflammatory and oxidative markers. MASLD group had a higher adiposity index, systolic blood pressure, glucose, plasma and liver triglycerides and cholesterol, insulin, hepatic steatosis, oxidative markers, and lower PPAR-α (Peroxisome Proliferator-activated receptor α), compared to the Co. CAR attenuated plasma and hepatic triglyceride and cholesterol levels, hepatic steatosis, CD68+ macrophages, and hepatic oxidative markers, in addition to increasing HDL cholesterol levels and PPAR-α, compared to the untreated MASLD group. CAR acts in importants pathophysiological processes of MASLD and may be a therapeutic compound to control the disease.

"Golden" Tomato Consumption Ameliorates Metabolic Syndrome: A Focus on the Redox Balance in the High-Fat-Diet-Fed Rat

Tomato fruits defined as "golden" refer to a food product harvested at an incomplete ripening stage with respect to red tomatoes at full maturation. The aim of this study is to explore the putative influence of "golden tomato" (GT) on Metabolic Syndrome (MetS), especially focusing on the effects on redox homeostasis. Firstly, the differential chemical properties of the GT food matrix were characterized in terms of phytonutrient composition and antioxidant capacities with respect to red tomato (RT). Later, we assessed the biochemical, nutraceutical and eventually disease-modifying potential of GT in vivo in the high-fat-diet rat model of MetS. Our data revealed that GT oral supplementation is able to counterbalance MetS-induced biometric and metabolic modifications. Noteworthy is that this nutritional supplementation proved to reduce plasma oxidant status and improve the endogenous antioxidant barriers, assessed by strong systemic biomarkers. Furthermore, consistently with the reduction of hepatic reactive oxygen and nitrogen species (RONS) levels, treatment with GT markedly reduced the HFD-induced increase in hepatic lipid peroxidation and hepatic steatosis. This research elucidates the importance of food supplementation with GT in the prevention and management of MetS.

Bergamot (Citrus bergamia) leaf extract improves metabolic, antioxidant and anti-inflammatory activity in skeletal muscles in a metabolic syndrome experimental model

Metabolic Syndrome (MetS), inflammation and oxidative stress contribute to impairment of skeletal muscle function. Bergamot (Citrus bergamia) leaf extract (BLE) has shown protective effects against comorbidities associated with MetS through its anti-inflammatory and antioxidant effects. The aim of this work was to elucidate the antioxidant and anti-inflammatory activity of BLE in skeletal muscles in an experimental model of MetS. Once metabolic syndrome was diagnosed, animals were divided into groups receiving different treatments for 10 weeks, including control diet (n = 10), control + BLE (n = 10), High Sugar-fat diet (HSF) (n = 10), HSF + BLE (n = 10). Evaluation included nutritional, metabolic and hormonal analyses, along with measurements of inflammatory status and oxidative stress in soleus and extensor digitorum longus (EDL) muscles. BLE showed positive metabolic effects, with a reduction of plasma triglycerides and insulin resistance and an increase in high-density lipoprotein cholesterol, and protective activity against oxidative stress and inflammation in Soleus and EDL muscles in animals with MetS.

Evaluation of Oxidative Status in Elderly Patients with Multiple Cerebral Infarctions and Multiple Chronic Total Coronary Occlusions

Background. Oxidative stress plays a key role in atherosclerosis. Acting via high level of reactive oxygen species, an increase of oxidative stress is involved in the pathogenesis and progression of atherosclerostic stenosis or occlusion of arteries. Oxidative stress leads to an accumulation of oxidized low-density lipoprotein, which plays important roles in steno-occlusion of cerebral and coronary arteries. However, the exact reasons for multiple cerebral and coronary artery steno-occlusion in elderly patients remain unclear. The aim was to evaluate the effects of imbalance of oxidative/antioxidative status on concomitant multiple brain infarcts and multiple chronic total coronary occlusions in elderly patients. Methods. We measured the circulating levels of malondialdehyde (MDA), reactive oxygen species (ROS), thiobarbituric acid reactive substance (TBARS), advanced oxidation protein products (AOPP), superoxide dismutase 1 (SOD 1), superoxide dismutase 2 (SOD 2), superoxide dismutase 3 (SOD 3), and paraoxonase 1 (PON 1) in patients with concomitant multiple cerebral infarcts and multiple chronic total coronary occlusions. Results. Circulating levels of oxidative stress markers (MDA, ROS, TBARS, and AOPP) were increased ( $P<0.001$ ) and antioxidative stress markers (SOD 1, SOD 2, SOD 3, and PON 1) were decreased ( $P<0.001$ ) in elderly patients with concomitant multiple brain infarcts and multiple chronic total coronary occlusions. Conclusions. The findings suggested that the imbalance of oxidative/antioxidative status may be associated with multiple cerebral infarcts and multiple chronic total coronary occlusions and may contribute to the development of concomitant multiple brain infarcts and multiple chronic total coronary occlusions in elderly patients.

Antioxidant and anti-inflammatory properties of gamma- oryzanol attenuates insulin resistance by increasing GLUT- 4 expression in skeletal muscle of obese animals

BACKGROUND

Skeletal muscle is the most important organ for whole-body glucose homeostasis. However, it has been suggested that obesity-related inflammation could be involved in insulin resistance and diabetes mellitus type 2 (DM2) development due several mechanisms, among them, the reduced expression of the glucose transporter type 4 (GLUT-4). Gamma-oryzanol (γOz) is a compound present in the whole grain of rice that presents anti-inflammatory and antioxidant activities. The aim of this study was to verify if the effect antioxidant and anti-inflammatory of yOz attenuate insulin resistance in skeletal muscle of obese rats by increasing GLUT- 4 expression.

METHODS

Male Wistar rats (±187 g) were initially randomly distributed into 2 experimental groups (control, n = 6, and high sugar-fat diet (HSF), n = 12) for 20 weeks. At week 20th of this study, once obesity and insulin resistance were detected in the HSF group, animals were divided to begin the treatment with γOz or continue receiving HSF for 10 more weeks. At the end it was analyzed nutritional, metabolic, inflammatory and oxidative stress parameters and GLUT-4 protein expression.

RESULTS

The treatment improved insulin resistance, reduced inflammation, increased antioxidant response and GLUT-4 expression.

CONCLUSION

It is possible to conclude that the antioxidant and anti-inflammatory activity of yOz attenuates insulin resistance by increasing GLUT-4 expression in skeletal muscle of obese animals.

Rice (Oryza sativa L.) bran preserves cardiac function by modulating pro-inflammatory cytokines and redox state in the myocardium from obese rats

Purpose

This study aimed to evaluate the effect of rice bran (RB) supplementation to a high-sugar fat (HSF) diet on cardiac dysfunction in an experimental obesity model.

Methods

Male Wistar rats were distributed into three groups: control, high-sugar fat, and high-sugar fat supplemented with 11% RB for 20 weeks.

Results

HSF diet promoted obesity and metabolic complications. Obese rats showed cardiac structural and functional impairment associated with high levels of interleukin-6, tumoral necrosis factor alpha, and malondialdehyde, and decreased activity of superoxide dismutase and catalase in the myocardium. RB supplementation was able to mitigate obesity and its metabolic alterations in HSF diet-fed animals. Moreover, the RB also prevented structural and functional damage, inflammation, and redox imbalance in the heart of these animals.

Conclusion

This study suggests that RB supplementation prevents cardiac dysfunction in rats fed on HSF by modulating systemic metabolic complications and inflammation and oxidative stress in the myocardium, representing potential alternative therapy.

Relationship between Innate Immune Response Toll-Like Receptor 4 (TLR-4) and the Pathophysiological Process of Obesity Cardiomyopathy

Fundamento

A obesidade é uma condição inflamatória crônica de baixo grau relacionada a distúrbios cardíacos. No entanto, o mecanismo responsável pela inflamação cardíaca relacionada à obesidade não é claro. O receptor do tipo toll 4 (TLR-4) pertence a um receptor da família das transmembranas, responsável pela resposta imune, cuja ativação estimula a produção de citocinas pró-inflamatórias.

Objetivo

Testar se a ativação do receptor TLR-4 participa do processo de cardiomiopatia da obesidade, devido à produção de citocinas por meio da ativação do NF-ĸB.

Métodos

Ratos Wistar machos foram randomizados em dois grupos: o grupo controle (C, n = 8 animais) que recebeu dieta padrão/água e o grupo obeso (OB, n = 8 animais) que foi alimentado com dieta rica em açúcar e gordura e água mais 25% de sacarose por 30 semanas. Análise nutricional: peso corporal, índice de adiposidade, alimentos, água e ingestão calórica. Análise de distúrbios relacionados à obesidade: glicose plasmática, ácido úrico e triglicerídeos, HOMA-IR, pressão arterial sistólica, TNF-α no tecido adiposo. A análise cardíaca incluiu: expressão das proteínas TLR-4 e NF-ĸB, níveis de TNF-α e IL-6. Comparação pelo teste t de Student não pareado ou teste de Mann-Whitney com um valor de p <0,05 como estatisticamente significativo.

Resultados

O grupo OB apresentou obesidade, glicose elevada, triglicerídeos, ácido úrico, HOMA, pressão arterial sistólica e TNF-α no tecido adiposo. O grupo OB apresentou remodelação cardíaca e disfunção diastólica. A expressão de TLR-4 e NF-ĸB e os níveis de citocinas foram maiores em OB.

Conclusão

Nossos achados concluem que, em uma condição obesogênica, a inflamação derivada da ativação do TLR-4 cardíaco pode ser um mecanismo capaz de levar à remodelação e disfunção cardíaca.

Lycopene corrects metabolic syndrome and liver injury induced by high fat diet in obese rats through antioxidant, anti-inflammatory, antifibrotic pathways

Obesity is a global epidemic disease that is closely associated with various health problems as Diabetes mellitus, cardiovascular, and metabolic disorders. Lycopene (LYC), a red-colored carotenoid, has demonstrated various promising therapeutic effects. Hence, the potential of LYC was studied against high fat diet (HFD)-induced obesity and metabolic disturbances in rats. Animals fed on HFD and orally supplemented with LYC (25 and 50 mg/kg) or simvastatin (10 mg/kg) every day for 3 months. The results revealed that long-term consumption of HFD significantly increased weight gain, liver weight, cholesterol, triglycerides (TG), apolipoprotein-B (Apo-B), low-density lipoprotein-cholesterol (LDL-c) levels, as well as decreasing the high-density lipoprotein-cholesterol (HDL-c) levels. Moreover, high blood glucose and insulin levels accompanied by low peroxisome proliferator activated receptor gamma (PPAR-γ) were recorded in HFD group. Further, HFD rats displayed lower levels of antioxidant biomarkers (SOD, CAT, GPx, GR and GSH), in addition to higher levels of MDA, NO and inflammatory mediators (IL-1β, TNF-α, and MPO). Marked increases were observed in atherogenic index, lactate dehydrogenase and creatine kinase together with fibrosis markers (TGF-β1 and α-SMA) in rats fed on HFD. Comparing to model group, LYC was able to effectively reverse HFD-mediated alterations at dose dependent manner. Altogether, dietary supplementation of LYC successfully reversed HFD-induced alterations through its antioxidant, anti-inflammatory, and anti-fibrotic properties. Hence, LYC displayed a therapeutic potential to manage obesity and its associated pathologies.

Gamma-oryzanol reduces renal inflammation and oxidative stress by modulating AGEs/RAGE axis in animals submitted to high sugar-fat diet

Introduction:

The receptor for AGEs (RAGE) is a multiligand member of the immunoglobulin superfamily of cell surface receptors expressed in many organs, among them, the kidneys. When activated, RAGE leads to a sequence of signaling that results in inflammation and oxidative stress, both involved in kidney disease pathogenesis. Gamma-oryzanol (γOz) comprises a mixture of ferulic acid (FA) esters and phytosterols (sterols and triterpene alcohols) mainly found in rice, with antioxidant and anti-inflammatory activities.

Aim:

To evaluate the effect of γOz to reduce renal inflammation and oxidative stress by modulating AGEs/RAGE axis in animals submitted to a high sugar-fat diet.

Methods:

Male Wistar rats (±187g) were randomly divided into two experimental groups: control (n = 7 animals) and high sugar-fat diet (HSF, n = 14 animals) for 20 weeks. After this period, when the presence of renal disease risk factors was detected in the HSF group (insulin resistance, dyslipidemia, increased systolic blood pressure and obesity), the HSF animals were divided to begin the treatment with γOz or continue receiving only HSF for 10 more weeks.

Results:

No effect of γOz on obesity and metabolic parameters was observed. However, kidney inflammation and oxidative stress decreased as soon as RAGE levels were reduced in HSF + γOz.

Conclusion:

It is possible to conclude that the gamma- oryzanol was effective in reducing inflammation and oxidative stress in the kidney by modulating the AGEs/RAGE axis.

The effects of two types of Western diet on the induction of metabolic syndrome and cardiac remodeling in obese rats

Metabolic syndrome (MetS) include obesity as a critical feature and is strongly associated with risk of cardiovascular disease (CVD). Insights into mechanisms involved in the pathophysiology of these clinical manifestations are essential for the development of therapeutic strategies. Thus, Western diets (WD) have been widely employed in diet-induced obesity (DIO) model. However, there are variations in fat and sugar proportions of such diets, making comparisons challenging. We aimed to assess the impact of two types of the WD on metabolic status and cardiac remodeling, to achieve a DIO model that better mimics the human pathogenesis of MetS-induced CVD. Male Wistar rats were distributed into three groups: control diet, Western diet fat (WDF), and Western diet sugar (WDS) for 41 weeks. Metabolic and inflammatory parameters and cardiac changes were characterized. WDF and WDS feeding promoted higher serum triglycerides, glucose intolerance, and insulin resistance, while just WDF presented inflammation in adipose tissue. WDF-fed rats showed increased catalase activity and malondialdehyde (MDA) and carbonyl protein levels, suggesting cardiac oxidative stress, while WDS-fed rats only raised MDA. Both WD equally elevated protein expressions involved in lipid metabolism, but only WDF downregulated the glycolysis pathway. Furthermore, the mechanical myocardial function was impaired in obese rats, being more relevant in WDF. In conclusion, both WD effectively triggered MetS features, although inflammation was detected just on the WDF-fed animals. Moreover, the WDF promoted a more pronounced functional, metabolic, and oxidative cardiac disorder, suggesting to be an adequate model for studying CVD in the scenario of MetS.

Soluble guanylate cyclase chronic stimulation effects on cardiovascular reactivity in cafeteria diet-induced rat model of metabolic syndrome

Metabolic syndrome is linked to an increased risk of cardiovascular complications by a mechanism involving mainly decreased nitric oxide (NO) bioavailability and impaired NO-soluble guanylate cyclase (sGC)- cyclic guanosine monophosphate (cGMP) signalling (NO-sGC-cGMP). To further develop this scientific point, this study aimed to investigate the effects of long-term treatment with BAY 41-2272 (a sGC stimulator) on cardiovascular reactivity of spontaneously hypertensive rats (SHR) as a model of metabolic syndrome. SHR were randomly divided into 3 groups: control group, cafeteria diet (CD)-fed group and CD-fed group treated daily with BAY 41-2272 (5 mg/kg) by gastric gavage for 12 weeks. In vivo measurements of body weight, abdominal circumference, blood pressure and glucose tolerance test were performed. At the end of the feeding period, ex vivo cumulative concentration-response curves were performed on isolated perfused heart (isoproterenol (0.1 nM - 1 μM)) and thoracic aorta (phenylephrine (1 nM-10 μM), acetylcholine (1 nM-10 μM), and sodium nitroprusside (SNP) (0.1 nM-0.1 μM)). We showed that chronic CD feeding induced abdominal obesity, hypertriglyceridemia, glucose intolerance and exacerbated arterial hypertension in SHR. Compared to control group, CD-fed group showed a decrease in β-adrenoceptor-induced cardiac inotropy, in coronary perfusion pressure and in aortic contraction to phenylephrine. While relaxing effects of acetylcholine and SNP were unchanged. BAY 41-2272 long-term treatment markedly prevented arterial hypertension development and glucose intolerance, enhanced the α1-adrenoceptor-induced vasoconstriction, and restored cardiac inotropy and coronary vasodilation. These findings suggest that BAY 41-2272 may be a potential novel drug for preventing metabolic and cardiovascular complications of metabolic syndrome.