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Oxidative stress plays a key role in the initiation and progression of metabolic diseases, including obesity. Preventing the accumulation of reactive oxygen species and oxidative damage to macromolecules is a beneficial strategy for reducing comorbidities associated with obesity. Fruits from the Spondias genus are known for their antioxidant activity, but they are not available year-round due to their seasonality. In this context, we investigated the antioxidant activity and identified the chemical constituents of the aqueous extract of the stem bark of Spondias purpurea L. (EBSp). Additionally, we evaluated the effect of EBSp consumption on metabolic parameters in mice with obesity induced by a high-fat diet. Chemical analyses revealed 19 annotated compounds from EBSp, including flavan-3-ols, proanthocyanidins, methoxylated coumarin, and gallic and ellagic acids, besides other phenolic compounds. In vitro, EBSp showed antioxidant activity through the scavenging of the free radicals and the protection of macromolecules against oxidative damage. Cellular assays revealed that EBSp reduced the levels of malondialdehyde produced by erythrocytes exposed to the oxidizing agent AAPH. Flow cytometry studies showed that EBSp reduced reactive oxygen species levels in human peripheral blood mononuclear cells treated with hydrogen peroxide. Obese mice treated with EBSp (400 mg.kg -1 ) for 60 days showed reduced levels of malondialdehyde in the heart, liver, kidneys, and nervous system. The total cholesterol levels in mice treated with EBSp reached levels similar to those after treatment with the drug simvastatin. Together, the results show that the combination of the different phenolic compounds in S. purpurea L. bark promotes antioxidant effects in vitro and in vivo, resulting in cytoprotection in the context of oxidative stress associated with obesity and a reduction in hypercholesterolemia. From a clinical perspective, the reduction in oxidative stress in obese individuals contributes to the reduction in the emergence of comorbidities associated with this metabolic syndrome., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Kátia A. Antunes et al.)

Polyphenols have demonstrated several potential biological activities, notably antitumoral activity dependent on immune function. In the present review, we describe studies that investigated antitumor immune responses influenced by polyphenols and the mechanisms by which polyphenols improve the immune response. We also discuss the limitations in related areas, especially unexplored areas of research, and next steps required to develop a therapeutic approach utilizing polyphenols in oncology., (Copyright © 2020. Published by Elsevier Inc.)

Background: End-stage renal disease results in B cell lymphopenia and low levels of vitamin D. Since the link between vitamin D deficiency and B lymphocytes dysfunction are not clear in patients with end-stage renal disease, we suggest that vitamin D adequacy and factors related to the homeostasis of these cells should be investigated. B lymphocytes homeostasis is a process mainly regulated signals of grown and death as interleukin (IL)-7, B cell-activating factor (BAFF)/BAFF-receptor and CD95 expression., Objective: As vitamin D serum levels were reduced in patients with end stage renal disease and it is associated with human B homeostasis, we evaluated the effect of cholecalciferol supplementation on dialysis., Design: Randomized, double blind clinical trial in dialysis patients with 25OH Vitamin D deficiency for a period of 12 weeks., Main Outcome Measure: In a pilot study, we investigated the effect of cholecalciferol supplementation (100,000 UI once per week or placebo. In vitro, peripheral blood mononuclear cells isolated by Ficoll-Hypaque centrifugation from 12 healthy volunteers were incubated with healthy or uremic serum in the presence or absence of 25 (OH)DC with 5% CO., Results: There was an increase in the serum 25(OH)D level in the cholecalciferol group. No differences were found in BAFF and IL7 levels and CD95 and BAFF-R expression in B lymphocytes from patients on dialysis after cholecalciferol supplementation. Uremic serum induced an increase in the IL-7, BAFF, BAFF-R and CD95 expression compared with the control. However, we observed no effect of incubation of 25(OH)D3 and 1,25(OH)2D3 on the expression of IL-7, BAFF, BAFF-R and CD95 when incubated in the presence of normal or uremic serum., Conclusion: Our results suggest that vitamin D is not involved in mechanisms of regulation of differentiation and survival in B lymphocytes. In conclusion, further studies are needed to explore the effects of vitamin D on B lymphocytes to better evaluate the possible impact of vitamin D on humoral response in the CKD population., (Published by Elsevier Inc.)

Vitamin D possesses renoprotective effects beyond mineral metabolism, potentially reducing arterial blood pressure and inflammation and vitamin D enzymes (CYP24A1 and CYP27B1) as well as vitamin D receptor (VDR) contribute to its homeostasis. In the present study, we aimed to determine vitamin D association with kidney volume, blood pressure parameters and inflammatory markers in ADPKD. This cross-sectional study, conducted from August 2011 through May 2016, evaluated 25(OH)D, 1,25(OH)2D and other hormonal/biochemical serum and urinary parameters, inflammatory markers and monocyte expression of VDR, CYP24A1, CYP27B1 in 74 ADPKD patients. The height-adjusted total kidney volume (htTKV) was determined by MRI and blood pressure (BP) measured through 24-h ambulatory BP monitoring (ABPM).Vitamin D insufficiency was present in 62% of patients and CYP24A1 was overexpressed in this group, raising a hypothesis of 25(OH)D increased catabolism. Serum 25(OH)D levels and VDR expression were negatively correlated with htTKV as was VDR with IL-6, IL-10, CRP, and NFκB. A multiple linear regression analysis with htTKV as dependent variable, including hypertension, CRP, eGFR, age, time since diagnosis, VDR, and 25(OH)D adjusted for season of the year showed that only the first three parameters were independent predictors of the former. There has been no association of serum 25(OH)D and VDR expression with ABPM parameters. Present findings suggested that low levels of serum 25(OH)D and VDR expression are associated with a higher kidney volume in ADPKD patients, but do not represent independent risk factors for htTKV.