Diabetic polyneuropathy (DPN) is defined as peripheral nerve dysfunction. There are three main alterations involved in the pathologic changes of DPN: inflammation, oxidative stress, and mitochondrial dysfunction. Inflammation induces activation of nuclear factor kappa B, activator protein 1, and mitogen-activated protein kinases. Oxidative stress induced by hyperglycemia is mediated by several identified pathways: polyol, hexosamine, protein kinase C, advanced glycosylation end-products, and glycolysis. In addition, mitochondrial dysfunction accounts for most of the production of reactive oxygen and nitrosative species. These free radicals cause lipid peroxidation, protein modification, and nucleic acid damage, to finally induce axonal degeneration and segmental demyelination. The prevalence of DPN ranges from 2.4% to 78.8% worldwide, depending on the diagnostic method and the population assessed (hospital-based or outpatients). Risk factors include age, male gender, duration of diabetes, uncontrolled glycaemia, height, overweight and obesity, and insulin treatment. Several diagnostic methods have been developed, and composite scores combined with nerve conduction studies are the most reliable to identify early DPN. Treatment should be directed to improve etiologic factors besides reducing symptoms; several approaches have been evaluated to reduce neuropathic impairments and improve nerve conduction, such as oral antidiabetics, statins, and antioxidants (alpha-lipoic acid, ubiquinone, and flavonoids).

Oxidative stress (OS) has the ability to damage different molecules and cellular structures, altering the correct function of organs and systems. OS accumulates in the body by endogenous and exogenous mechanisms. Increasing evidence points to the involvement of OS in the physiopathology of various chronic diseases that require prolonged periods of pharmacological treatment. Long-term treatments may contribute to changes in systemic OS. In this review, we discuss the involvement of OS in the pathological mechanisms of some chronic diseases, the pro- or antioxidant effects of their pharmacological treatments, and possible adjuvant antioxidant alternatives. Diseases such as high blood pressure, arteriosclerosis, and diabetes mellitus contribute to the increased risk of cardiovascular disease. Antihypertensive, lipid-lowering, and hypoglycemic treatments help reduce the risk with an additional antioxidant benefit. Treatment with methotrexate in autoimmune systemic inflammatory diseases, such as rheumatoid arthritis, has a dual role in stimulating the production of OS and producing mitochondrial dysfunction. However, it can also help indirectly decrease the systemic OS induced by inflammation. Medicaments used to treat neurodegenerative diseases tend to decrease the mechanisms related to the production of reactive oxygen species (ROS) and balance OS. On the other hand, immunosuppressive treatments used in cancer or human immunodeficiency virus infection increase the production of ROS, causing significant oxidative damage in different organs and systems without widely documented exogenous antioxidant administration alternatives.

The purpose of this study was to evaluate serum leptin levels in systemic lupus erythematosus (SLE). Forty-one women with SLE were compared with 23 healthy women of similar age and body mass index (BMI). Clinical characteristics and Mexican systemic lupus erythematosus disease activity index (Mex-SLEDAI) score were assessed. Serum leptin levels (ng/dl) were measured by enzyme-linked immunosorbent assay (ELISA). Comparisons of leptin levels were made with the Mann-Whitney U-test. In a multiple regression analysis, those factors that could influence the leptin levels were adjusted. Patients with SLE had higher leptin levels than the control group (SLE median 31 vs control median 15, P=0.023). After adjusting by other variables, the serum leptin levels remained higher in SLE than in controls (P=0.02). Patients with SLE had no association between leptin levels and Mex-SLEDAI score, age, duration of disease, or prednisone doses. Those with SLE had higher leptin levels than controls. Further longitudinal studies are required to evaluate the role of this hormone in the exacerbations of SLE.

Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus (DM) causing vision impairment even at young ages. There are numerous mechanisms involved in its development such as inflammation and cellular degeneration leading to endothelial and neural damage. These mechanisms are interlinked thus worsening the diabetic retinopathy outcome. In this review, we propose oxidative stress as the focus point of this complication onset.

The aim of this study was to compare the efficacy of intravenous cyclophosphamide (IVCYC) versus oral enalapril in mild or moderate pulmonary hypertension (PH) in systemic lupus erythematosus (SLE). Thirty-four patients with SLE who had systolic pulmonary artery pressure (SPAP) > 30 mmHg by Doppler echocardiography were randomized to receive IVCYC (0.5 g/mt2 body surface area, monthly), or oral enalapril (10 mg/day) for six months. The primary outcome was the significant decrease in SPAP. An additional outcome measure included the improvement in the heart functional class (NYHA). Sixteen patients received cyclophosphamide and 18 enalapril. IVCYC decreased the median values of SPAP from 41 to 28 mmHg (P < 0.001), and enalapril from 35 to 27 mmHg (P = 0.02). IVCYC reduced more than twice as much SPAP than enalapril (P = 0.04). In those patients with SPAP > or = 35 mmHg, cyclophosphamide decreased from 43 to 27 mmHg (P = 0.003), but enalapril was not effective (P = 0.14). The NYHA functional class improved only in those with cyclophosphamide (P = 0.021). Also IVCYC had a higher frequency of side effects including infections (RR = 1.6; 95% CI, 1.001-2.47), and gastrointestinal side effects (RR = 14.6; 95% CI, 2.15-99.68). We concluded that IVCYC was effective in mild and moderate PH associated with SLE. Further research is needed to evaluate its long-term efficacy.

Objective. To evaluate whether serum titers of second-generation anticyclic citrullinated peptide antibodies (anti-CCP2) are associated with the severity and extent of interstitial lung disease in rheumatoid arthritis (RA-ILD). Methods. In across-sectional study, 39 RA-ILD patients confirmed by high-resolution computed tomography (HRCT) were compared with 42 RA without lung involvement (RA only). Characteristics related to RA-ILD were assessed in all of the patients and serum anti-CCP2 titers quantified. Results. Higher anti-CCP2 titers were found in RA-ILD compared with RA only (medians 77.9 versus 30.2 U/mL, P < 0.001). In the logistic regression analysis after adjustment for age, disease duration (DD), smoke exposure, disease activity, functioning, erythrocyte sedimentation rate, and methotrexate (MTX) treatment duration, the characteristics associated with RA-ILD were higher anti-CCP2 titers (P = 0.003) and + RF (P = 0.002). In multivariate linear regression, the variables associated with severity of ground-glass score were anti-CCP2 titers (P = 0.02) and with fibrosis score DD (P = 0.01), anti-CCP2 titers (P < 0.001), and MTX treatment duration (P < 0.001). Conclusions. Anti-CCP2 antibodies are markers of severity and extent of RA-ILD in HRCT. Further longitudinal studies are required to identify if higher anti-CCP2 titers are associated with worst prognosis in RA-ILD.

Our data show a high prevalence of hyperhomocysteinaemia in Mexican patients with RA. More effort is required to evaluate and treat earlier this coronary risk factor.

IntroductionThere are controversial results about the role of serum leptin and adiponectin levels as biomarkers of the severity of proteinuria in lupus nephritis.ObjectiveThe aim of this study was to evaluate the relationship between serum leptin and adiponectin levels with severity of proteinuria secondary to lupus nephritis (LN).MethodsIn a cross-sectional study, 103 women with systemic lupus erythematosus (SLE) were evaluated for kidney involvement. We compared 30 SLE patients with LN, all of them with proteinuria, versus 73 SLE patients without renal involvement (no LN). A comprehensive set of clinical and laboratory variables was assessed, including serum levels of leptin and adiponectin by ELISA. Multivariate analyses were used to adjust for potential confounders associated with proteinuria in LN.ResultsWe found higher adiponectin levels in the LN group compared with the no LN group (20.4 ± 10.3 vs 15.6 ± 7.8 μg/mL; p = 0.02), whereas no differences were observed in leptin levels (33.3 ± 31.4 vs 22.5 ± 25.5 ng/mL; p = 0.07). Severity of proteinuria correlated with an increase in adiponectin levels (r = 0.31; p = 0.001), but no correlation was observed with leptin. Adiponectin levels were not related to anti-dsDNA or anti-nucleosome antibodies. In the logistic regression, adiponectin levels were associated with a high risk of proteinuria in SLE (OR = 1.06; 95% CI 1.01–1.12; p = 0.02). Instead, leptin was not associated with LN.ConclusionThese findings indicate that adiponectin levels are useful markers associated with proteinuria in LN. Further longitudinal studies are required to identify if these levels are predictive of renal relapse.