Effect of Roux-en-Y Bariatric Bypass Surgery on Subclinical Atherosclerosis and Oxidative Stress Markers in Leukocytes of Obese Patients: A One-Year Follow-Up Study

The Impact of Weight Loss on Inflammation, Oxidative Stress, and Mitochondrial Function in Subjects with Obesity

Inflammation, oxidative stress, and mitochondrial function are implicated in the development of obesity and its comorbidities. The purpose of this study was to assess the impact of weight loss through calorie restriction on the metabolic profile, inflammatory and oxidative stress parameters, and mitochondrial respiration in an obese population. A total of 109 subjects underwent two cycles of a very low-calorie diet alternated with a low-calorie diet (24 weeks). We analyzed biochemical and inflammatory parameters in serum, as well as oxidative stress markers, mRNA antioxidant gene expression, and mitochondrial respiration in peripheral blood mononuclear cells (PBMCs). After the intervention, there was an improvement in both insulin resistance and lipid profiles, including cholesterol subfractions. Weight loss produced a significant reduction in mitochondrial ROSs content and an increase in glutathione levels, coupled with an enhancement in the mRNA expression of antioxidant systems (SOD1, GSR, and CAT). In addition, a significant improvement in basal oxygen consumption, maximal respiration, and ATP production was observed. These findings demonstrate that moderate weight loss can improve insulin resistance, lipid profiles and subfractions, inflammatory and oxidative stress parameters, and mitochondrial respiration. Therefore, we can affirm that dietary intervention can simultaneously achieve significant weight loss and improve metabolic profile and mitochondrial function in obesity.

Oxidative Stress in Postbariatric Patients: A Systematic Literature Review Exploring the Long-term Effects of Bariatric Surgery

Background

The present study investigates the impact of oxidative stress after bariatric surgery in patients with obesity. This field of study has gained great interest in recent years due to the role that oxidative stress plays in metabolic diseases. Obesity, by itself, can generate an increase in reactive oxygen and nitrogen species, intensifying cellular damage and promoting the progression of adverse metabolic conditions. In this context, bariatric surgery emerges as a candidate capable of modifying oxidative stress biomarkers, facilitating the patient's metabolic recovery.

Methods

A systematic review was carried out, identifying 30 studies found in databases such as PubMed, Scopus, Web of Science, and Google Scholar. It looked at the link between oxidative stress and recovery after bariatric surgery in patients. The selection of studies was based on the measurement of oxidative stress biomarkers before and after surgical intervention.

Results

The results reveal a significant decrease in oxidative stress biomarkers after bariatric surgery. However, a notable variability in antioxidant activity is observed between different patients, as well as a significant influence of comorbidities.

Conclusions

Bariatric surgery is postulated as an effective intervention in reducing oxidative stress in patients with obesity, enhancing antioxidant activity and improving patient recovery. This finding highlights the importance of considering oxidative stress management as an integral part of postoperative care, suggesting the need to implement complementary treatment strategies to optimize health outcomes.

Novel Role of Molecular Hydrogen: The End of Ophthalmic Diseases?

Molecular hydrogen (H2) is a colorless, odorless, and tasteless gas which displays non-toxic features at high concentrations. H2 can alleviate oxidative damage, reduce inflammatory reactions and inhibit apoptosis cascades, thereby inducing protective and repairing effects on cells. H2 can be transported into the body in the form of H2 gas, hydrogen-rich water (HRW), hydrogen-rich saline (HRS) or H2 produced by intestinal bacteria. Accumulating evidence suggest that H2 is protective against multiple ophthalmic diseases, including cataracts, dry eye disease, diabetic retinopathy (DR) and other fields. In particular, H2 has been tested in the treatment of dry eye disease and corneal endothelial injury in clinical practice. This medical gas has brought hope to patients suffering from blindness. Although H2 has demonstrated promising therapeutic potentials and broad application prospects, further large-scale studies involving more patients are still needed to determine its optimal application mode and dosage. In this paper, we have reviewed the basic characteristics of H2, and its therapeutic effects in ophthalmic diseases. We also focus on the latest progress in the administration approaches and mechanisms underlying these benefits.

Protein Carbonylation Contributes to Prothrombotic Fibrin Clot Phenotype in Acute Ischemic Stroke: Clinical Associations

BACKGROUND

Acute ischemic stroke (AIS) is associated with enhanced oxidative stress and unfavorably altered fibrin clot properties. We investigated determinants of plasma protein carbonylation (PC) in AIS, its impact on the prothrombotic state, and prognostic value during follow-up.

METHODS

We included 98 consecutive AIS patients aged 74±12 years (male:female ratio, 50:48 [51%:49%]) at the Neurology Center in Warsaw, Poland, between January and December 2014. As many as 74 (75.5%) patients underwent thrombolysis, and 24 were unsuitable for thrombolysis. We determined plasma PC, along with thrombin generation, fibrin clot permeability, and clot lysis time on admission, at 24 hours, and 3 months. Stroke severity was assessed using the National Institutes of Health Stroke Scale and stroke outcome with the modified Rankin Scale. Hemorrhagic transformation was assessed on the computed tomography scan within 48 hours from the symptom onset, while stroke-related mortality was evaluated at 3 months.

RESULTS

On admission, PC levels (median, 4.61 [3.81-5.70] nM/mg protein) were associated with the time since symptom onset (r=0.41; P<0.0001) and with the National Institutes of Health Stroke Scale score (P=0.36; P=0.0003). Higher PC levels on admission correlated with denser fibrin clot formation and prolonged clot lysis time but not with thrombin generation. In thrombolysed patients, lower PC levels were observed after 24 hours (-34%) and at 3 months (-23%; both P<0.001). PC levels at baseline and after 24 hours predicted the modified Rankin Scale score >2 at 3 months (OR, 1.90 [95% CI, 1.21-3.00]; OR, 2.19 [95% CI, 1.39-3.44], respectively). Higher PC at baseline predicted hemorrhagic transformation of stroke (OR, 1.95 [95% CI, 1.02-3.74]) and stroke-related mortality (OR, 2.02 [95% CI, 1.08-3.79]), while higher PC at 24 hours predicted solely stroke-related mortality (OR, 2.11 [95% CI, 1.28-3.46]).

CONCLUSIONS

Elevated plasma PC levels in patients with AIS, related to prothrombotic fibrin clot properties, are associated with stroke severity. Thrombolysis reduces the extent of PC. The current study suggests a prognostic value of PC in AIS.

Established and potential cardiovascular risk factors in metabolic syndrome: Effect of bariatric surgery

PURPOSE OF REVIEW

The aim of this review was to provide an overview of the role of novel biomarkers in metabolic syndrome, their association with cardiovascular risk and the impact of bariatric surgery on these biomarkers.

RECENT FINDINGS

Metabolic syndrome encompasses an intricate network of health problems, and its constituents extend beyond the components of its operational definition. Obesity-related dyslipidaemia not only leads to quantitative changes in lipoprotein concentration but also alteration in qualitative composition of various lipoprotein subfractions, including HDL particles, rendering them proatherogenic. This is compounded by the concurrent existence of obstructive sleep apnoea (OSA) and nonalcoholic fatty liver disease (NAFLD), which pave the common pathway to inflammation and oxidative stress culminating in heightened atherosclerotic cardiovascular disease (ASCVD) risk. Bariatric surgery is an exceptional modality to reverse both conventional and less recognised aspects of metabolic syndrome. It reduces the burden of atherosclerosis by ameliorating the impact of obesity and its related complications (OSA, NAFLD) on quantitative and qualitative composition of lipoproteins, ultimately improving endothelial function and cardiovascular morbidity and mortality.

SUMMARY

Several novel biomarkers, which are not traditionally considered as components of metabolic syndrome play a crucial role in determining ASCVD risk in metabolic syndrome. Due to their independent association with ASCVD, it is imperative that these are addressed. Bariatric surgery is a widely recognized intervention to improve the conventional risk factors associated with metabolic syndrome; however, it also serves as an effective treatment to optimize novel biomarkers.

Effect of bariatric surgery on atherogenicity and insulin resistance in patients with obesity class II: a prospective study

OBJECTIVE

Enormous efforts have been made to evaluate reliable, simple and practical indicators for predicting patients at risk of progression of cardiovascular disease events, whereby bariatric surgery has remained understudied. Thus, we performed this study to assess the effect of bariatric surgery procedures on atherogenicity and insulin resistance indicators.

DESIGN

Cohort study.

SETTING, PARTICIPANTS AND OUTCOME MEASURES

Four hundred and forty-three class II obese (severely obese) patients who underwent sleeve gastrectomy, Roux-en-Y gastric bypass, or one anastomosis gastric bypass were followed up for 12 months after surgery. Atherosclerosis-related indicators were evaluated at baseline, as well as 6 and 12 months after surgery.

RESULTS

Atherogenic index of plasma, lipoprotein combine index, atherogenic coefficient, cholesterol index, Castelli's risk indices I and II, and triglyceride to high-density lipoprotein-cholesterol ratio (p<0.01) improved after 12 months. Additionally, bariatric surgery yielded a significantly reduced triglyceride glucose index. There was no significant difference between procedures in terms of indicators. The Spearman correlation test showed a significant inverse correlation between weight plus fat mass and atherosclerosis-related indicators as well as a positive correlation between percentage of excess weight loss and these indicators.

CONCLUSIONS

This study demonstrated three bariatric surgery procedures' ability to improve atherogenicity and insulin resistance in patients with obesity class II. The anti-atherogenicity effects can be partly assigned to the reduction of body weight and adipose tissue. Nevertheless, further studies with larger sample sizes and longer follow-ups are required to confirm our results.

Impact of Bariatric Surgery on the Stability of the Genetic Material, Oxidation, and Repair of DNA and Telomere Lengths

Obesity causes genetic instability, which plays a key-role in the etiology of cancer and aging. We investigated the impact of bariatric surgery (BS) on DNA repair, oxidative DNA damage, telomere lengths, alterations of antioxidant enzymes and, selected proteins which reflect inflammation. The study was realized with BS patients (n = 35). DNA damage, base oxidation, BER, and NER were measured before and 1 month and 6 months after surgery with the single-cell gel electrophoresis technique. SOD and GPx were quantified spectrophotometrically, malondealdehyde (MDA) was quantified by HPLC. Telomere lengths were determined with qPCR, and plasma proteome profiling was performed with high-resolution mass spectrophotometry. Six months after the operations, reduction of body weight by 27.5% was observed. DNA damage decreased after this period, this effect was paralleled by reduced formation of oxidized DNA bases, a decline in the MDA levels and of BER and NER, and an increase in the telomere lengths. The activities of antioxidant enzymes were not altered. Clear downregulation of certain proteins (CRP, SAA1) which reflect inflammation and cancer risks was observed. Our findings show that BS causes reduced oxidative damage of DNA bases, possibly as a consequence of reduction of inflammation and lipid peroxidation, and indicate that the surgery has beneficial long-term health effects.

Impact of Roux-en-Y Gastric Bypass on Mitochondrial Biogenesis and Dynamics in Leukocytes of Obese Women

The chronic low-grade inflammation widely associated with obesity can lead to a prooxidant status that triggers mitochondrial dysfunction. To date, Roux-en-Y gastric bypass (RYGB) is considered the most effective strategy for obese patients. However, little is known about its molecular mechanisms. This interventional study aimed to investigate whether RYGB modulates oxidative stress, inflammation and mitochondrial dynamics in the leukocytes of 47 obese women at one year follow-up. We evaluated biochemical parameters and serum inflammatory cytokines -TNFα, IL6 and IL1β- to assess systemic status. Total superoxide production -dHe-, mitochondrial membrane potential -TMRM-, leucocyte protein expression of inflammation mediators -MCP1 and NF-kB-, antioxidant defence -GPX1-, mitochondrial regulation—PGC1α, TFAM, OXPHOS and MIEAP- and dynamics -MFN2, MNF1, OPA1, FIS1 and p-DRP1- were also determined. After RYGB, a significant reduction in superoxide and mitochondrial membrane potential was evident, while GPX1 content was significantly increased. Likewise, a marked upregulation of the transcription factors PGC1α and TFAM, complexes of the oxidative phosphorylation chain (I–V) and MIEAP and MFN1 was observed. We conclude that women undergoing RYGB benefit from an amelioration of their prooxidant and inflammatory status and an improvement in mitochondrial dynamics of their leukocytes, which is likely to have a positive effect on clinical outcome.

NADPH Oxidases Connecting Fatty Liver Disease, Insulin Resistance and Type 2 Diabetes: Current Knowledge and Therapeutic Outlook

Nonalcoholic fatty liver disease (NAFLD), characterized by ectopic fat accumulation in hepatocytes, is closely linked to insulin resistance and is the most frequent complication of type 2 diabetes mellitus (T2DM). One of the features connecting NAFLD, insulin resistance and T2DM is cellular oxidative stress. Oxidative stress refers to a redox imbalance due to an inequity between the capacity of production and the elimination of reactive oxygen species (ROS). One of the major cellular ROS sources is NADPH oxidase enzymes (NOX-es). In physiological conditions, NOX-es produce ROS purposefully in a timely and spatially regulated manner and are crucial regulators of various cellular events linked to metabolism, receptor signal transmission, proliferation and apoptosis. In contrast, dysregulated NOX-derived ROS production is related to the onset of diverse pathologies. This review provides a synopsis of current knowledge concerning NOX enzymes as connective elements between NAFLD, insulin resistance and T2DM and weighs their potential relevance as pharmacological targets to alleviate fatty liver disease.

Oxidative Stress in Obesity

Obesity is defined by the World Health Organization (WHO) as abnormal or excessive fat accumulation that presents a health risk [...]

Roux-en-Y Gastric Bypass Modulates AMPK, Autophagy and Inflammatory Response in Leukocytes of Obese Patients

Obesity is characterized by low-grade chronic inflammation, metabolic overload, and impaired endothelial and cardiovascular function. Roux-en-Y gastric bypass (RYGB) results in amelioration of the pro-oxidant status of leukocytes and the metabolic profile. Nevertheless, little is known about the precise mechanism that drives systemic and metabolic improvements following bariatric surgery. In this cohort study, we investigated the effect of RYGB on molecular pathways involving energy homeostasis in leukocytes in 43 obese subjects one year after surgery. In addition to clinical and biochemical parameters, we determined protein expression of systemic proinflammatory cytokines by Luminex®, different markers of inflammation, endoplasmic reticulum (ER) stress, autophagy/mitophagy by western blot, and mitochondrial membrane potential by fluorescence imaging. Bariatric surgery induced an improvement in metabolic outcomes that was accompanied by a systemic drop in hsCRP, IL6, and IL1β levels, and a slowing down of intracellular inflammatory pathways in leukocytes (NF-κB and MCP-1), an increase in AMPK content, a reduction of ER stress (ATF6 and CHOP), augmented autophagy/mitophagy markers (Beclin 1, ATG5, LC3-I, LC3-II, NBR1, and PINK1), and a decrease of mitochondrial membrane potential. These findings shed light on the specific molecular mechanisms by which RYGB facilitates metabolic improvements, highlighting the relevance of pathways involving energy homeostasis as key mediators of these outcomes. In addition, since leukocytes are particularly exposed to physiological changes, they could be used in routine clinical practice as a good sensor of the whole body’s responses.