This is the first study to evaluate both the antioxidant barrier, glutathione metabolism, and oxidative damage to proteins and lipids in morbidly obese patients undergoing bariatric treatment. The study included 65 patients with class 3 obesity divided into two subgroups: morbidly obese patients without metabolic syndrome (OB) and obese patients with metabolic syndrome (OB + MS). Blood samples were collected before surgery as well as one, three, six, and twelve months after the bariatric treatment. Superoxide dismutase and reduced glutathione (GSH) were significantly decreased, whereas glutathione reductase and uric acid were enhanced in morbidly obese patients before bariatric surgery as compared to lean control. Moreover, in the OB group, we observed the increase of superoxide dismutase (SOD) and the decrease of uric acid (UA) after the bariatric treatment; however, these changes were not observed in the OB + MS group. The oxidative damage to proteins (advanced glycation end products, AGE; advanced oxidation protein products, AOPP) and lipids (8-isoprostanes, 8-isop; 4-hydroxynoneal) was higher in OB as well as OB + MS patients. We noticed that AGE and AOPP levels diminished after the bariatric treatment, whereas redox status (ratio of GSH to oxidized glutathione) was still reduced in the OB + MS group. Summarizing, morbid obesity is associated with disturbances in the antioxidant barrier and enhanced oxidative damage to proteins and lipids. Although bariatric surgery improves redox homeostasis in obese patients, those with metabolic syndrome show a continuous decrease in the antioxidant status. In patients undergoing bariatric treatment, antioxidant supplementation may be considered.

Introduction Laparoscopic adrenalectomy has become the gold standard of surgical treatment for benign adrenal masses. Two alternative surgical approaches are currently advocated: the lateral transperitoneal approach (LTA) and the posterior retroperitoneal approach (PRA). Several randomized trials have compared LTA to PRA, but most of them included small numbers of patients or had stringent inclusion criteria. Aim To compare clinical results of LTA and PRA endoscopic adrenalectomies for tumors < 8 cm with wide inclusion criteria. Material and methods We randomized 77 patients to either LTA (n = 33) or PRA (n = 44). The groups were comparable in terms of age, gender proportions, body mass index, tumor size, clinical and pathological diagnosis. We analyzed duration of surgery, intraoperative blood loss, postoperative pain, length of hospital stay and postoperative morbidity. Results The follow-up concerned 98.8% of patients and was on average 28 (8–47) months long. There were no conversions. We identified significantly lower intensity of pain assessed 24 h after surgery in the PRA group (3.4 ±1), as compared to LTA (4.2 ±1), with lower prevalence of shoulder pain (2.3% vs. 30.3%, respectively). Postoperative hospital stay was shorter in the PRA (1.14 ±0.4) than in the LTA (1.36 ±0.5) group. Perioperative morbidity concerned 4 patients in each group with pain requiring oral analgesia > 7 days. Conclusions To our knowledge this is the largest prospective randomized study comparing LTA to PRA. We demonstrated safety, efficacy and very low morbidity of both techniques. The PRA proved superior to LTA in terms of lower intensity of postoperative pain and shorter hospital stay.

In this pathbreaking study, we evaluated nitrosative stress in morbidly obese patients with and without metabolic syndrome. 62 women with class 3 obesity (BMI>40 kg/m2) were divided into three subgroups: obese patients (OB), obese patients with hypertension (OB+HYP), and obese patients with metabolic syndrome (OB+MS). In comparison to the lean patients, OB had increased levels of serum myeloperoxidase (MPO), plasma nitric oxide (NO), S-nitrosothiols, and peroxynitrite (ONOO−), as well as nitrotyrosine, while oxidized glutathione (GSSG) rose only in OB+HYP group. Interestingly, ONOO− was significantly higher in OB+HYP and OB+MS as compared to OB group, while MPO only in OB+MS group. OB+MS had greater nitrotyrosine and S-nitrosothiol values than OB+HYP. Moreover, peroxynitrite could differentiate OB from OB+HYP and OB+MS (AUC 0.9292; p<0.0001; 87.5% sensitivity, 90% specificity) as well as between OB and OB+MS group (AUC 0.9125; p<0.0001; 81.25% sensitivity, 83.33%). In conclusion, we showed that MPO activity, NO formation, and nitrosative damage to proteins parallel the progression of metabolic disturbances of obesity. Evaluation of ONOO− concentrations may help predict the development of hypertension and metabolic syndrome in patients with morbid obesity; however, longer-term studies are required for larger numbers of patients.

The results of recent studies indicate the key role of nitrosative stress and protein oxidative damage in the development of morbid obesity. Nevertheless, the effect of bariatric surgery on protein oxidation/glycation and nitrosative/nitrative stress is not yet known. This is the first study evaluating protein glycoxidation and protein nitrosative damage in morbidly obese patients before and after (one, three, six and twelve months) laparoscopic sleeve gastrectomy. The study included 50 women with morbid obesity as well as 50 age- and gender-matched healthy controls. We demonstrated significant increases in serum myeloperoxidase, plasma glycooxidative products (dityrosine, kynurenine, N-formyl-kynurenine, amyloid, Amadori products, glycophore), protein oxidative damage (ischemia modified albumin) and nitrosative/nitrative stress (nitric oxide, peroxy-nitrite, S-nitrosothiols and nitro-tyrosine) in morbidly obese subjects as compared to lean controls, whereas plasma tryptophan and total thiols were statistically decreased. Bariatric surgery generally reduces the abnormalities in the glycoxidation of proteins and nitrosative/nitrative stress. Noteworthily, in the patients with metabolic syndrome (MS+), we showed no differences in most redox biomarkers, as compared to morbidly obese patients without MS (MS-). However, two markers: were able to differentiate MS+ and MS- with high specificity and sensitivity: peroxy-nitrite (>70%) and S-nitrosothiols (>60%). Further studies are required to confirm the diagnostic usefulness of such biomarkers.

The assessment of total antioxidant activity seems to have a higher diagnostic value than the evaluation of individual antioxidants separately. Therefore, this is the first study to assess the total antioxidant/oxidant status in morbidly obese patients undergoing bariatric surgery. The study involved 60 patients with Class 3 obesity (BMI > 40 kg/m2) divided into two equal subgroups: morbidly obese patients without and with metabolic syndrome. The analyses were performed in plasma samples collected before surgery as well as 1, 3, 6, and 12 months after a laparoscopic sleeve gastrectomy. Total antioxidant capacity (TAC), ferric-reducing antioxidant power (FRAP), DPPH (2,2′-diphenyl-1-picrylhydrazyl) radical assay, and total oxidant status (TOS) were significantly higher before surgery (as compared to the healthy controls, n = 60) and generally decreased after bariatric treatment. Interestingly, all assessed biomarkers correlated positively with uric acid content. However, the total antioxidant/oxidant potential did not differ between obese patients without metabolic syndrome and those with both obesity and metabolic syndrome. Only DPPH differentiated the two subgroups (p < 0.0001; AUC 0.8) with 73% sensitivity and 77% specificity. Plasma TAC correlated positively with body mass index, waist–hip ratio, serum insulin, and uric acid. Therefore, TAC seems to be the best biomarker to assess the antioxidant status of obese patients.