Níveis séricos de vitamina D e urinários de KIM-1 e MCP-1 em pacientes com anemia falciforme / Serum levels of vitamin D, and urinary levels of KIM-1 and MCP-1 in patients with sickle cell anemia

Objetivo: realizar dosagens de biomarcadores de função renal não convencionais em pacientes com anemia falciforme e associar com os níveis séricos de vitamina D. Métodos: trata-se de um estudo observacional, analítico de corte transversal. Participaram do estudo 51 pacientes adultos com anemia falciforme, e o grupo controle foi composto por 17 adultos saudáveis doadores de sangue. Os níveis séricos de 25- hidroxi-vitamina D foram determinados por imunoensaio quimioluminecente de micropartículas (CMIA), e a função renal foi avaliada pelas dosagens de molécula-1 de lesão renal (KIM-1) e proteína-1 quimiotática de monócitos (MCP-1). Os resultados foram expressos como mediana (intervalo interquartil). Os testes t-Student de amostras independentes, análise de variância de Welch e teste não paramétrico de Kruskal-Wallis foram realizados para comparar as diferenças entre os grupos. Resultados: os pacientes apresentaram níveis séricos de vitamina D superiores ao grupo controle, além de uma maior prevalência de suficiência de vitamina D. Os níveis urinários de KIM-1 e MCP-1 estavam aumentados nos pacientes em relação ao grupo controle. Não houve relação entre baixos níveis séricos de vitamina D e a probabilidade de desenvolvimento de doença renal. Conclusões: este estudo fornece dados importantes sobre a prevalência da deficiência de vitamina D em pacientes com anemia falciforme e demonstra não haver relação entre baixos níveis de vitamina D e desenvolvimento de doença renal.

Objective: to measure non-conventional renal function biomarkers in patients with sickle cell anemia and associate them with serum levels of vitamin D. Method: this is an observational, analytical, cross-sectional study. Fifty-one adult patients with sickle cell anemia participated in the study, and the control group consisted of 17 healthy adult blood donors. Serum levels of 25-hydroxyvitamin D were determined by chemiluminescent microparticle immunoassay (CMIA), and renal function was assessed by measuring urinary Kidney Injury Molecule-1 (KIM-1) and Monocyte Chemoattractant Protein-1 (MCP-1). Results were expressed as median (interquartile range). Student's t-test, Welch analysis of variance, and non-parametric Kruskal-Wallis test were performed to compare differences between groups. Results: patients had higher serum levels of vitamin D than the control group, besides a higher prevalence of vitamin D sufficiency. Urinary levels of KIM-1 and MCP-1 were increased in patients compared to the control group. There was no relationship between low serum vitamin D levels and the likelihood of developing kidney disease. Conclusions: this study provides important data on the prevalence of vitamin D deficiency in patients with sickle cell anemia and demonstrates that there is no relationship between low levels of vitamin D and the development of kidney disease.

Association of serum lipoproteins and inflammatory parameters derived from the blood test with renal function in COVID-19 outpatients

Abstract Changes in lipoprotein metabolism are among the main causes of hemodynamic impairment in renal function. COVID-19 is an multisystemic inflammatory disease, aggravating this situation. This cross-sectional study investigated the relationship of serum lipoprotein profile with inflammatory parameters and renal function in 95 COVID-19 outpatients in comparison with 173 with flu-like symptoms. Serum samples were collected for the determination of total cholesterol and fractions, apolipoproteins (Apo A-I and Apo B), urea (sUr) and creatinine (sCr). The glomerular filtration rate (eGFR) was calculated. Neutrophil/lymphocyte (NLR) and platelet/lymphocyte (PLR) ratios were calculated as inflammatory parameters derived from the blood tests. COVID-19 patients presented lower high-density lipoprotein cholesterol (HDL-c) (47.90 ± 1.543 vs. 51.40 ± 0.992) and higher PLR (190.9 ± 9.410 vs. 137.6 ± 5.534) and NLR (3.40 ± 0.22 vs. 2.80 ± 0.15). Both NLR and PLR correlated with each other (r = 0.639). Furthermore, the Apo B/Apo A-I ratio was correlated with PLR (r = 0.5818) and eGFR (r = -0.2630). COVID-19 patients classified as at high risk of developing acute myocardial infarction based on the Apo B/ Apo A-I ratio had higher values for sUr/sCr. Thus, serum apolipoproteins, PLR, and NLR could be related to renal dysfunction in COVID-19.

Tyramine exerts hypolipidemic and anti-obesity effects in vivo

Abstract Obesity and dyslipidemia are conditions often associated with cardiovascular risk, inflammation, oxidative stress, and death. Thus, a new approach has been highlighted to promote research and development of pharmacological tools derived from natural sources. Among the most widely studied groups of substances, polyphenols such as tyramine stand out. This study investigated hypolipidemic and anti-obesity properties of tyramine. Oral toxicity evaluation, models of dyslipidemia and obesity were used. To induce dyslipidemia, Poloxamer-407 (P-407) was administered intraperitoneally. In the hypercholesterolemic and obesity model, specific diet and oral tyramine were provided. After 24h of P-407 administration, tyramine 2 mg/kg (T2) decreased triglycerides (TG) (2057.0 ± 158.5 mg/dL vs. 2838 ± 168.3 mg/dL). After 48h, TG were decreased by T2 (453.0 ± 35.47 vs. 760.2 ± 41.86 mg/dL) and 4 mg/kg (T4) (605.8 ± 26.61 760.2 ± 41.86 mg/dL). T2 reduced total cholesterol (TC) after 24h (309.0 ± 11.17 mg/dL vs. 399.7 ± 15.7 mg/dL); After 48h, 1 mg/kg (T1) (220.5 ± 12.78 mg/dL), T2 (205.8 ± 7.1 mg/dL) and T4 (216.8 ± 12.79 mg/dL), compared to P-407 (275.5 ± 12.1 mg/dL). The treatment decreased thiobarbituric acid reactive substances and nitrite in liver, increased superoxide dismutase, reduced the diet-induced dyslipidemia, decreasing TC around 15%. Tyramine reduced body mass, glucose, and TC after hypercaloric feed. Treatment with 5 mg/L (0.46 ± 0.04 ng/dL) and 10 mg/L (0.44 ± 0.02 ng/dL) reduced plasma insulin (1.18 ± 0.23 ng/dL). Tyramine increased adiponectin at 5 mg/L (1.02 ± 0.02 vs. 0.83 ± 0.02 ng/mL) and 10mg/L (0.96 ± 0.04 ng/mL). In conclusion, tyramine has low toxicity in rodents, has antioxidant effect, reduces plasma triglycerides and cholesterol levels. However, further studies should be conducted in rodents and non-rodents to better understand the pharmacodynamic and pharmacokinetic properties of tyramine

Protective Effect of Quercetin on Renal Tubular Cells and the Involvement with the Renin-Angiotensin-Aldosterone Axis

Abstract Ischemia-reperfusion (I/R) plays an important role in the process of acute kidney injury (AKI) due to the generation of reactive oxygen species (ROS). Substances of natural origin have been studied in the prevention of oxidative damage related to I/R. Quercetin is a flavonoid with antioxidant potential and modulate enzymes, such the inhibition of the Rennin-Angiotensin System (RAS). The aim of this study is to evaluate the nephroprotective effect of quercetin against the I/R and analyze the inhibition of RAS. Rhesus monkey Kidney Epithelial Cells (LLC-MK2 line) were submitted to an in vitro ischemia/reperfusion model. After the reperfusion cells were treated with quercetin, the cell viability was accessed by the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. Tubular cell damage was assessed by the Kidney Injury Molecule-1 (KIM-1) measurement. Oxidative stress was evaluated through Thiobarbituric Acid Reactive Substances (TBARS) and reduced glutathione (GSH). The evaluation of cell death and the mitochondrial depolarization were analyzed by flow cytometry. Quercetin prevents cell death reducing oxidative stress and preventing mitochondrial membrane depolarization. Molecular docking showed that quercetin prevents cell damage better than losartan and lisinopril, inhibitors of RAS. Quercetin has a potential to interact with type 1 angiotensin II receptor (AT1) with greater affinity through the formation of five hydrogen bonds of strong intensity.