A deficiência de vitamina D (dVD) aumenta o risco de morte em pacientes hospitalizados. A injúria de isquemia/reperfusão renal (Isq) ativa vias de necrose e/ou apoptose e proliferação celular. A injúria renal aguda (IRA) induz a ativação de inibidores do ciclo celular, incluindo a p21, uma inibidora de kinase dependente de ciclina, a qual possui efeito protetor na IRA. A p21 é um alvo genômico da 25-hidroxivitamina D [25 (OH) D], a qual, atuando através de receptores de vitamina D (VDRs), possui efeitos imunomoduladores potentes e antiproliferativos, sugerindo a participação deste hormônio na fisiopatologia da doença renal. Desta forma, o objetivo deste estudo foi verificar a participação da deficiência de vitamina D no modelo de isquemia/reperfusão renal em ratos. Foram utilizados ratos Wistar que foram divididos em quatro grupos: controle (C), animais que receberam dieta padrão por 30 dias; dVD, animais que receberam dieta livre de vitamina D por 30 dias; Isq, animais que receberam dieta padrão por 30 dias e no 28º dia foram submetidos ao insulto de isquemia/reperfusão em ambos os rins por 45 minutos; e dVD+Isq, animais que receberam dieta livre de vitamina D por 30 dias e no 28º dia foram submetidos ao insulto de isquemia/reperfusão em ambos os rins por 45 minutos. Ao final dos 30 dias e após 48 horas da realização da isquemia/reperfusão, os animais foram submetidos à eutanásia e amostras de sangue, urina e tecido renal foram coletados para o estudo dos mecanismos de lesão renal. A injúria renal aguda associada à deficiência de vitamina D levou a uma queda da filtração glomerular e aumento da proteinúria; aumento da relação peso renal/peso corporal, sugerindo maior proliferação e hipertrofia; induziu uma diminuição na ativação dos receptores de vitamina D e da expressão da proteína p21 e aumento da expressão de caspase-3; observou-se déficit de concentração urinária com diminuição da expressão da AQP2; e um maior dano morfológico caracterizado pela análise da área intersticial e presença de necrose tubular. Nossos dados mostraram que alterando os níveis da p21 na IRA isquêmica, a vitamina D, via VDRs, controla a inflamação renal, a proliferação e a lesão celular / Vitamin D deficiency (VDD) increases the risk of death in hospitalized patients. Ischemia/reperfusion injury activates pathways of necrosis and/or apoptosis and cell proliferation. Acute kidney injury (AKI) induces the activation of cell cycle inhibitors, including p21, an inhibitor of cyclin-dependent kinase, which has a protective effect on the IRA. The p21 is a genomic target of 25-hydroxyvitamin D [ 25 (OH) D], which, acting through vitamin D receptors (VDRs), has potent antiproliferative and immunomodulatory effects, suggesting the involvement of this hormone in the pathophysiology of renal disease. Thus, the aim of this study was to assess the role of vitamin D deficiency in rats submitted to renal ischemia/reperfusion. Wistar rats were divided into four groups: control (C), animals that received a standard diet for 30 days; VDD, animals that received vitamin D-free diet for 30 days; IRI, animals that received standard diet for 30 days and on day 28 were subjected to the ischemia/reperfusion insult (IRI) in both kidneys for 45 minutes; and VDD+IRI, animals that received vitamin D-free diet for 30 days and on day 28 were subjected to the IRI in both kidneys for 45 minutes. At the end of 30 days and 48 hours after the IRI insult, the animals were euthanized and samples of blood, urine and kidney tissue were collected to study the mechanisms of renal injury. Acute kidney injury associated with vitamin D deficiency led to a decrease in glomerular filtration rate and increased proteinuria; increased relative kidney weight/body weight, suggesting greater proliferation and hypertrophy; induced a decrease in the activation of vitamin D receptors and the p21 protein expression and, increased caspase-3 expression; renal concentration impairment with decreased AQP2 expression, as well as greater morphological damage characterized by interstitial area analysis and presence of tubular necrosis. Our data showed that altering the levels of p21 in ischemic-AKI, vitamin D via VDRs, controls kidney inflammation, proliferation and cell injury

A metionina sintase redutase (MTRR) catalisa a redução da cobalamina (Cbl) oxidada a metilcobalamina. Em presença de folato, a metionina sintase (MTR) utiliza a metilcobalamina como cofator na metilação da homocisteína (tHcy) a metionina. O objetivo deste estudo foi avaliar os efeitos dos polimorfismos MTR A2756G e MTRR A66G nas concentrações dos metabólitos marcadores de deficiência de Cbl e folato em gestantes e neonatos. Os genótipos dos polimorfismos MTR A2756G e MTRR A66G foram obtidos por PCR-RFLP. O genótipo MTR 2756AA foi relacionado aos maiores valores de tHcy em gestantes e MMA em neonatos. Gestantes com genótipos MTRR 66AG e GG e com menores concentrações de Cbl apresentaram maior risco de apresentar concentrações elevadas de tHcy. Neonatos com genótipos com MTRR 66AG e GG apresentaram menores valores de SAM. Os polimorfismos MTR A2756G e MTRR A66G interferem nas reações dependentes de Cbl e folato em gestantes e neonatos. / Methionine synthase reductase (MTRR) catalyzes the reductive reaction of oxidized cobalamin to methylcobalamin. When folate is present, methionine synthase (MTR) uses methylcobalamin cofactor at homocysteine to methionine methylation process. The aim of this study was to evaluate the effects of MTR A2756G and MTRR A66G polymorphisms on total homocysteine (tHcy), methylmalonic acid (MMA), S-adenosylmethionine (SAM) concentrations and SAM/SAH ratio in Brazilian pregnant women and their newborns. Genotypes of two polymorphisms were determined by PCR-RFLP. MTR 2756AA genotype was associated with higher tHcy and MMA levels in mothers and babies, respectivelly. Lower cobalamin concentrations associated with MTRR 66AG and GG genotypes increased risk to elevated tHcy levels in pregnant women. The SAM levels were lower in neonates with MTRR 66AG e GG genotypes. The polymorphisms MTR A2756G and MTRR A66G could affect cobalamin and folate dependent reactions in pregnant women and newborns.

<p>Uvod: Hepatička osteodistrofija je termin koji obuhvata metaboličke bolesti kosti udružene sa hroničnim bolestima jetre. U alkoholnoj cirozi (AC) jetre postoji visoka zastupljenost deficijencije vitamina D proporcionalna stepenu disfunkcije jetre, ali njena uloga u patogenezi hepatičke osteodistrofije nije dovoljno obja&scaron;njena. Nivo 25(OH)D odražava status vitamina D. Kod AC jetre izmenjena je metabolička aktivnost kosti i suprimirano je formiranje kosti &scaron;to dovodi do smanjenja ko&scaron;tane mase. U centru interesovanja je postizanje optimalnog statusa vitamina D. Stavovi o suplementaciji vitaminom D kod AC jetre nisu jasno definisani. Cilj rada: Utvrditi nivo vitamina D, ispitati metaboličku aktivnost kosti i mineralnu gustinu kosti kod bolesnika sa AC jetre. Utvrditi efekte suplementacije sa 1000 IU vitamina D3 na dan tokom godinu dana u odnosu na metaboličku aktivnost kosti i mineralnu gustinu kosti kod ispitivanih bolesnika. Bolesnici i metode: Istraživanje je sprovedeno na Klinici za gastroenterologiju i hepatologiju Kliničkog centra Vojvodine u Novom Sadu kao prospektivna intervencijska studija sa primenom suplementacije sa 1000 IU vitamina D3 na dan kod bolesnika sa AC jetre. Grupu bolesnika koja je uključena u istraživanje (1) činilo je 70 bolesnika mu&scaron;kog pola sa dijagnozom AC jetre. Bolesnici su imali četiri pregleda (P), odnosno tačke studije: P1-uključivanje bolesnika i započinjanje suplementacije vitaminom D; P2, P3 i P4 posle tri, &scaron;est i dvanaest meseci suplementacije vitaminom D, redom. Prilikom svakog pregleda rađene su analize funkcije jetre, metabolizma kosti i statusa vitamina D. Na početku (P1) i na kraju istraživanja (P4) vr&scaron;eno je merenje mineralne gustine kosti (BMD) DXA metodom. Gubitak bolesnika od P1 do P4 bio je dvadeset, na različitim tačkama studije. Prvi deo istraživanja odnosi se na Grupu bolesnika koja je uključena u istraživanje (1) i zavr&scaron;ila prvi pregled (P1). Pedeset bolesnika je zavr&scaron;ilo kompletno istraživanje po predviđenom protokolu i oni se zbog realizacije svih pregleda i ponovljenih merenja posmatraju kao: Grupa bolesnika koja je zavr&scaron;ila istraživanje (2). Rezultati: (1): Kod bolesnika sa AC jetre utvrđena je deficijencija vitamina D, snižen nivo osteokalcina, normalni nivoi CrossLapsa, PTH, ukupnog i jonizovanog kalcijuma, fosfora i magnezijuma. Osteopeniju je imalo 42,65% a osteoporozu 14,71% ispitanika. Kod svih ispitanika najniži BMD izmeren je na vratu femura. (2): Suplementacija vitaminom D dovela je do značajnog porasta 25(OH)D. U odnosu na osteokalcin konstatovana je pozitivna razlika vrednosti P1/P4, iako je nivo ostao ispod donje granice normale. Kod nivoa CrossLapsa i PTH razlika P1/P4 je negativna, ali su nivoi u sva četiri merenja u okviru referentnih vrednosti. Na lumbalnoj kičmi do&scaron;lo je do pobolj&scaron;anja BMD za 0.87%, a pogor&scaron;anja su na vratu femura -1.87 % i kuku -1.65%. Konstatovano je i pobolj&scaron;anje funkcije jetre. Zaključci: Kod bolesnika sa AC jetre pobolj&scaron;anje statusa vitamina D dovodi do povećanja formiranja kosti i pobolj&scaron;anja ko&scaron;tane mase na lumbalnoj kičmi. Neophodno je određivanje statusa vitamina D kod svih bolesnika sa AC jetre i uvođenje suplementacije vitaminom D kod bolesnika koji imaju nivo 25(OH)D &lt; 80 nmol/l, uz tromesečne kontrole efekta. Kod postavljanja dijagnoze AC jetre potrebno je inicijalno određivanje BMD. Kod suplementacije vitaminom D nakon inicijalnog DXA pregleda sledeći se preporučuje nakon jedne do dve godine.</p> / <p>Introduction: The term Hepatic osteodystrophy defines a group of metabolic bone diseases associated with underlying chronic liver disease. Alcoholic liver cirrhosis (ALC) is characterized by high incidence of vitamin D deficiency that is proportional to the level of liver failure; however, its role in the pathogenesis of hepatic osteodystrophy has not yet been fully elucidated. The level of 25(OH)D best reflects the vitamin D status. ALC is characterized by changed bone metabolic activity and suppressed bone formation, resulting in the decrease in bone mass. The key topic of interest is the achievement of optimal vitamin D status. The attitude of health professionals towards vitamin D supplementation in alcoholic liver cirrhosis has not yet been clearly defined. The aim of the research: Determining of vitamin D levels, investigating the metabolic activity of the bone and bone mass in patients with alcoholic liver cirrhosis (ALC); Determining the effects of vitamin D3 supplementation at the dose 1000 IU/day during a one-year period in relation to metabolic activity of the bone and bone mineral density (BMD) in the investigated patient population. Patients and methods: The research was conducted at the Clinic for Gastroenterology and Hepatology of the Clinical Centre of Vojvodina in Novi Sad. The research was designed as a prospective interventional study implicating vitamin D3 supplementation at the dose 1000 IU/day to patients with ALC. The investigated patient population (1) encompassed 70 male patients diagnosed with ALC. The patients underwent four examinations (P), that is, research phases: P1 &ndash; inclusion of the patient into the study and introduction of vitamin D supplementation; P2, P3 and P4 after 3, 6 and 12 months of vitamin D supplementation treatment, respectively. Each examination included the analysis of liver function, bone metabolism and vitamin D status. At the beginning (P1) and at the end (P4) of the investigation period, bone mineral density (BMD) was measured by means of dual-energy x-ray absorptiometry (DXA) method. Twenty patients dropped out from the research at different stages throughout the investigation period (P1 to P4). The first part of the investigation pertains to the Group of patients who were included into the study (1) and completed the first examination (P1). Fifty patients have completed the entire research according to the foreseen protocol encompassing all examinations and repeated measurements. These patients are considered a Group of patients who completed the research (2) Results: (1): In ALC patients, vitamin D deficiency and decreased osteocalcin levels were established, as well as normal levels of CrossLaps, PTH, total and ionized calcium, phosphorus and magnesium. Osteopenia and osteoporosis were established in 42.65% and 14.71% of patients, respectively. The lowest BMD was measured in the femoral neck in all patients. (2): Vitamin D supplementation resulted in significant increase in 25(OH)D. Analysis of osteocalcin level revealed positive P1/P4 difference, even though the level remained below the lower normal limit. The levels of CrossLaps and PTH revealed negative P1/P4 difference; however, the levels determined at all four measurements were within the reference values. An improvement of BMD for 0.87% was established in lumbar spine, whereas a decrease was noticed in femoral neck (1.87%) and hip (1.65%). Furthermore, an improvement of liver function was established. Conclusions: Improvement of vitamin D status in ALC patients results in an increase of bone formation and improvement of body mass in lumbar spine. Determining the vitamin D status in all patients with ALC is of outmost importance, as well as the vitamin D supplementation of patients with levels of 25(OH)D &lt; 80 nmol/l along with the monitoring of treatment outcome at three-month intervals. Establishment of the diagnosis of alcoholic liver cirrhosis should encompass initial measurement of BMD. In case of vitamin D supplementation treatment, the initial DXA examination should be repeated after the period of one to two years.</p>

<p>Zastupljenost deficita vitamina D3 je mnogo veći kod bolesnika sa dijabetesnom bolesti tipa 2 nego u populaciji zdravih osoba. Bolesnici sa DM tipa 2 i deficitom vitamina D3 imaju veći rizik za razvoj dijabetesne nefropatije. Eksperimenti na životinjama i neka klinička istraživanja ukazuju da bi primena nižih doza vitamina D3 mogla imati renoproktektivno delovanje. Cilj istraživanja je bio da se utvrdi zastupljenost deficita vitamina D3 u populaciji bolesnika sa dijabetesnom nefropatijom koja je definisana proteinurijom ˃0,150 g/du. Drugi cilj je bio da se utvrdi da li primena holekaciferola u dozi koja predstavlja razliku između utvrđenog i optimalnog nivoa vitamina D3 dovodi do statistički značajnog smanjenja proteinurije. Bolesnici sa dijabetesom tipa 2 i proteinurijom ˃0,150 g/du su uključivani u skrining na nivo vitamina D3 (25(OH)D) nakon čega su svrstavani u grupe sa deficitom i normalnim nivoom vitamina D3. Granična vrednost za utvrđivanje deficita vitamina D3 je odreĎivana na osnovu tabele koja defini&scaron;e ove vrednosti za svaki mesec tokom godine, posebno za mu&scaron;karce i žene. Bolesnici sa deficitom vitamina D3 su podeljeni u 2 grupe od po 45 ispitanika. Studijska grupa je primala holekaciferol u dozi koja je izračunata na osnovu razlike između izmerene vrednosti i određenog optimalnog nivoa vitamina D3 od 90-100 nmol/L. Kontrolna grupa bolesnika je uzimala svoju uobičajenu terapiju. Istraživanje je trajalo 24 nedelje tokom koje su na drugi mesec praćeni parametri bubrežne funkcije, parametri inflamacije i ko&scaron;tanog metabolizma. Na početku i kraju istraživanja su odreĎeni nivo vitamina D3 u studijskoj grupi, dok su u obe grupe određivani vrednost HbA1c i lipidni profil. Analizom dobijenih podataka je utvrđeno da je zastupljenost deficita vitamina D3 kod bolesnika sa dijabetesnom nefropatijom, uzimajući u obzir sezonske varijacije u nivou ovog vitamina, bila veća od vrednosti od 30-50% koje su postavljene u radnoj hipotezi. Učestalost bolesnika sa nedostakom vitamina D3 je u ispitivanom uzorku je bila 82,56% , dok je normalne vrednosti vitamina D3 imalo 17,43% ispitanika, od toga je bilo 10 (52,63%) mu&scaron;karaca i 9 (47,36%) žena. Sniženje vrednosti vitamina D3 u odnosu na donje granične vrednosti je bilo izraženije u letnjem periodu i bilo je statistički značajno kod svih ispitanika zajedno, potom u studijskoj grupi, dok je utvrđeno i u kontrolnoj grupi ali je u njoj bilo bez statisičke značajnosti. Utvrđen je porast HbA1c koji je bio veći u kontrolnoj grupi ispitanika. Suplementacija vitaminom D3 je imala povoljan efekat na lipidni profil. Registrovan je porast vrednosti ukupnog holesterola koji je bio izraženiji u kontrolnoj grupi, pad vrednosti triglicerida u grupi bolesnika koji su uzimali vitamin D3 i njihov porast u kontrolnoj grupi ispitanika. U studijskoj grupi je registrovan porast vrednosti HDL-holesterola koji je bio na granici statističke značajnosti dok je istovremeno nađeno njegovo smanjenje u kontrolnoj grupi. Vrednost LDL-holesterola je ostala bez promene pod delovanjem vitamina D3, dok je u kontrolnoj grupi do&scaron;lo do njegovog porasta. Utvrđeno je snižavanje vrednosti sedimentije, CRP-a i fibrinogena koje je bilo bez statističke značajnosti. Bezbednosni profil vrednosti kalcijuma u serumu i urinu tokom dugotrajnije primene je dobar. Primenom vitamina D3 je do&scaron;lo do signifikatnog smanjenja proteinurije u grupi bolesnika koji su primali holekaciferol čime je ujedno i potvrđena radna hipoteza.</p> / <p>The prevalence of vitamin D3 deficiency is much higher in patients with type 2 diabetes than in the healthy population. Patients with type 2 DM and vitamin D3 deficiency are at increased risk for developing diabetic nephropathy. Animal experiments and some clinical studies suggest that administration of lower doses of vitamin D3 could have renoprotective effect. The aim of the study was to determine the prevalence of vitamin D3 deficiency in the population of patients with diabetic nephropathy defined by proteinuria ˃0.150 g / du. The second goal was to determine whether the use of cholecaciferol in a dose that represents the difference between the established and optimal levels of vitamin D3 leads to a statistically significant reduction in proteinuria. Patients with type 2 diabetes and proteinuria ˃0.150 g / du were screened for vitamin D3 (25 (OH) D) levels and then classified as deficient and normal vitamin D3. The limit value for determining vitamin D3 deficiency was set on the basis of a table defining these values for each month during the year, separately for men and women. Patients with vitamin D3 deficiency were divided into 2 groups of 45 subjects each. The study group received cholecaciferol at a dose calculated on the basis of the difference between the measured value and the set optimal vitamin D 3 level of 90-100 nmol/L. The control group of patients was taking their usual therapy. The study lasted 24 weeks during which the parameters of renal function, parameters of inflammation and bone metabolism were monitored every second month. At the beginning and end of the study, the levels of vitamin D3 in the study group were determined, while in both groups HbA1c and lipid profile were determined. The analysis of the obtained data showed that the prevalence of vitamin D3 deficiency in patients with diabetic nephropathy, taking into account seasonal variations in the level of this vitamin, was higher than the values of 30-50%, which were set in the working hypothesis. The frequency of patients with vitamin D3 deficiency in the study sample was 82.56%, while the normal values of vitamin D3 were in 17.43% of the subjects, of which 10 (52.63%) were men and 9 (47.36%) woman. The decrease in vitamin D3 compared to the lower limit values was more pronounced in the summer and was statistically significant in all subjects together, as well in the study group, while it was also found in the control group but was not statistically significant. An increase in HbA1c was found to be higher in the control group. Vitamin D3 supplementation had a beneficial effect on the lipid profile. An increase in the total cholesterol level that was more pronounced in the control group, a decrease in triglyceride values in the group of patients taking vitamin D3 and its increase in the control group of subjects were registered. An increase in HDL-cholesterol was reported in the study group, which was at the limit of statistical significance, while at the same time a decrease was found in the control group. LDL-cholesterol levels remained unchanged under the influence of vitamin D3, while in the control group it increased. The decrease in sedimentation, CRP and fibrinogen values was found to be of no statistical significance. The safety profile of serum and urine calcium during long-term administration is good. The use of vitamin D3 resulted in a significant decrease in proteinuria in the group of patients receiving cholecaciferol, which also confirmed the working hypothesis.</p>

Aging increases the risk of both vitamin D deficiency and metabolic syndrome. Vitamin D deficiency and metabolic syndrome may be related, although there are mixed findings. Furthermore, literature suggests other factors such as physical fitness activity and smoking behavior are associated with Vitamin D deficiency and the development of metabolic syndrome. A number of studies have documented associations between Vitamin D levels and physical fitness activities, while other studies found correlations between Vitamin D levels, metabolic syndrome, and smoking behavior. However, no previous study has examined the links between physical fitness activity, smoking behavior, Vitamin D levels, and the risks for metabolic syndrome. The purpose of this study was to examine if smoking behavior and physical fitness activity moderated the relationship between Vitamin D deficiency and metabolic syndrome among older individuals. The research problem was addressed through the use of retrospective data collected from the National Health and Nutrition Examination Survey (NHANES) 2005-2006. This study utilized a quantitative, retrospective, cross-sectional design employing regression and correlational analysis to determine that Vitamin D deficiency (p = 0.02) predicts metabolic syndrome (n = 1570). However, neither physical activity (p = 0.99) nor smoking behavior (p = 0.23) moderated the relationship between Vitamin D deficiency and metabolic syndrome (n = 1570). The results of the study could give practitioners a better understanding and insights into the different risk factors to metabolic syndrome among older individuals, which can eventually enable primary and secondary prevention interventions.

Na maioria dos países, a incidência e prevalência da doença renal crônica (DRC) vem aumentando ao longo dos anos. Embora tenha havido uma melhora significativa no manejo da DRC com os inibidores do sistema renina-angiotensina-aldosterona, a doença ainda é progressiva, levando a necessidade do surgimento de novas estratégias protetoras. A fibrose renal progressiva está presente na DRC e envolve a participação de várias citocinas, com destaque para o fator Transforming growth factor- beta1 (TGF-beta1). Tem sido demonstrado que a mortalidade de pacientes com DRC está diretamente relacionada à função renal e está associada a riscos tradicionais como cardiovasculares e infecções. Entretanto, esses riscos tradicionais explicam apenas metade das causas de mortalidade nesses pacientes. Evidências crescentes mostram que o status de vitamina D pode ser um fator de risco não tradicional para a evolução da DRC. Tendo em vista o importante papel da vitamina D na manutenção das funções fisiológicas essenciais e a observação da queda dos níveis deste hormônio na DRC, torna-se relevante o estudo da deficiência de vitamina D nos eventos envolvidos na evolução crônica da lesão renal aguda em modelo experimental de isquemia/reperfusão renal. Ratos Wistar foram divididos em quatro grupos: controle, animais que receberam dieta padrão; dVD, animais que receberam dieta depletada em vitamina D; Isq, animais que receberam dieta padrão e foram submetidos ao insulto de isquemia/reperfusão renal bilateral no 28º dia; Isq+dVD, animais que receberam dieta depletada em vitamina D e foram submetidos ao insulto de isquemia/reperfusão bilateral no 28º dia. Ao final dos 90 dias do protocolo, os animais foram submetidos à eutanásia, amostras de sangue, urina e o tecido renal foram coletados para a análise dos mecanismos de lesão renal. Os animais submetidos ao insulto de isquemia/reperfusão renal apresentaram hipertrofia renal, aumento dos níveis de pressão arterial média, colesterol e de PTH plasmático. Além disso, foi observada expansão da área intersticial, aumento do infiltrado de macrófagos/monócitos, da expressão de colágeno IV, fibronectina, vimentina e alfa-actina e redução da expressão da proteína Klotho. A deficiência de vitamina D contribuiu para a elevação dos níveis plasmáticos de PTH e aumento da proteinúria assim como para as alterações túbulo-intersticiais crônicas importantes (fibrose e infiltrado inflamatório do interstício, dilatação e atrofia tubular), aumento da expressão da citocina TGF-beta1 expressão do receptor de vitamina D (VDR) e da proteína Klotho, observados nos animais deficientes em vitamina D submetidos ao insulto de isquemia/reperfusão renal. Portanto, através de vias inflamatórias e com participação do fator de crescimento TGF-beta1 ê um fator agravante para o dano túbulo-intersticial e formação de fibrose intersticial nesse modelo experimental de isquemia/reperfusão renal / In most countries, the incidence and prevalence of chronic kidney disease (CKD) has been increasing over the years. Although there was a significant improvement in the management of CKD with renin-angiotensin-system inhibitors, the disease is still progressive, leading to the need of emergence of new protective strategies. The progressive renal fibrosis is present in CKD and involves the participation of several cytokines, especially the Transforming growth factor-beta1 (TGF-beta1). It has been shown that the mortality of patients with CKD is directly related to renal function, which is associated to traditional risk factors such as cardiovascular diseases and infections. However, these traditional risk factors explain only half of the causes of mortality in these patients. Growing evidence shows that vitamin D status may be a non-traditional risk factor for the progression of CKD. Considering the important role of vitamin D in the maintenance of essential physiological functions and the observation of low levels of this hormone in CKD, the study of vitamin D deficiency in the events involved in chronic evolution of acute kidney injury in an experimental model of ischemia/reperfusion becomes relevant. Wistar rats were divided into four groups : control, animals received a standard diet ; dVD, animals received a vitamin D-depleted diet ; Isq, animals received a standard diet and were subjected to bilateral renal ischemia/reperfusion injury on day 28; Isq +dVD, animals received a vitamin D-depleted diet and were subjected to bilateral renal ischemia/reperfusion injury on day 28 . At the end of the 90 days of the protocol, the animals were euthanized and samples of blood, urine and kidney tissue were collected for analysis of the mechanisms of renal injury. The animals subjected to the insult of ischemia/ reperfusion showed renal hypertrophy, increased levels of mean blood pressure, cholesterol and plasma PTH. Furthermore, expansion of the interstitial area, increased infiltration of macrophages/monocytes, increased expression of collagen IV, fibronectin, vimentin and alpha-actin, and reduced expression of Klotho protein were observed. The vitamin D deficiency contributed to the elevation of plasma PTH levels and increased proteinuria as well as for important chronic tubulo-interstitial changes (fibrosis and inflammatory infiltration of the interstitium, tubular dilation and atrophy), increased expression of cytokine TGF-beta1 vitamin D receptor (VDR) and Klotho protein observed in vitamin D-deficient animals subjected to the insult of renal ischemia/reperfusion. Therefore, through inflammatory pathways and involvement of TGF-beta1 w y aggravating factor in tubulointerstitial damage and formation of interstitial fibrosis in this experimental model of renal ischemia/reperfusion

A Síndrome da Imunodeficiência Adquirida (AIDS) é um problema de saúde pública. O Tenofovir Disoproxil Fumarato (TDF) foi o primeiro inibidor do nucleotídeo da transcriptase reversa e é a droga mais recomendada para o tratamento da AIDS. Entretanto, o uso prolongado de TDF está associado com a nefrotoxicidade. A deficiência de vitamina D tem alta prevalência em indivíduos infectados com o Vírus da Imunodeficiência Humana (HIV). A vitamina D participa da regulação de atividades fisiológicas de diversos órgãos, incluindo o rim, oferecendo proteção contra as lesões ocasionadas por diferentes causas. Portanto, pacientes com níveis baixos de vitamina D infectados com o HIV podem apresentar complicações renais e cardiovasculares durante a terapia antirretroviral. Sendo assim, a carência desta vitamina pode acelerar a progressão da doença renal. Tendo em vista o aumento da incidência de hipovitaminose D na população mundial, esse trabalho tem o objetivo de verificar os mecanismos que levam ao desenvolvimento da lesão renal em ratos depletados de vitamina D submetidos ao tratamento com TDF. Ratos Wistar foram divididos em quatro grupos: controle, animais que receberam dieta padrão por 60 dias; dVD, animais que receberam dieta depletada em vitamina D por 60 dias; TDF, animais que receberam dieta padrão por 60 dias com a adição de TDF (50 mg/kg de dieta) nos últimos 30 dias; e dVD+TDF, animais que receberam dieta depletada em vitamina D por 60 dias com a adição de TDF nos últimos 30 dias. Ao final dos 60 dias, os animais foram submetidos à eutanásia, amostras de sangue, urina e o tecido renal foram coletados para a análise dos mecanismos de lesão renal. O tratamento com TDF levou a insuficiência renal observada pela queda da filtração glomerular e lesão tubular proximal com aparecimento de fosfatúria ocasionada pela diminuição do cotransportador sódio/fosfato subtipo IIa. Essas alterações foram acompanhadas de hipertensão e modificações no perfil lipídico. A deficiência em vitamina D associada à administração de TDF agravou os efeitos renovasculares e a nefrotoxicidade induzida pelo TDF, pelo menos em parte, devido ao aumento nos marcadores de estresse oxidativo e a participação do sistema renina-angiotensina-aldosterona. Portanto, é essencial monitorar os níveis de vitamina D em pacientes infectados com o HIV tratados com TDF / Acquired Immunodeficiency Syndrome (AIDS) has become one of the world\'s most serious health problem. Tenofovir Disoproxil Fumarate (TDF) was the first available nucleotidic reverse transcription inhibitor and is a widely prescribed antiretroviral medication for treatment of Human Immunodeficiency Virus (HIV). However, the long-term use of TDF has been associated with a number of toxicities, including those affecting the kidney. Vitamin D deficiency is prevalent among HIVinfected individuals. Vitamin D not only regulates numerous physiological activities of multiple organ systems, but also protects the kidney from injury from different causes. Thus, HIV-infected subjects with low levels of vitamin D could experience increased complications during antiretroviral therapy, such as cardiovascular disease and renal impairment. In view of the high worldwide incidence of hypovitaminosis D, the aim of this study was to investigate the effects of vitamin D deficiency on TDF-induced nephrotoxicity. Wistar rats were divided into four groups: control, receiving a standard diet for 60 days; dVD, receiving a vitamin D-free diet for 60 days; TDF, receiving a standard diet for 60 days with the addition of TDF (50 mg/kg food) for the last 30 days; and dVD+TDF receiving a vitamin D-free diet for 60 days with the addition of TDF for the last 30 days. At the end of the protocol, animals were euthanized and blood, urine and tissue samples were collected in order to evaluate the mechanisms responsible for renal injury. TDF led to impaired renal function, hyperphosphaturia, hypophosphatemia, hypertension and increased renal vascular resistance due to downregulation of the sodium-phosphorus cotransporter and upregulation of reninangiotensin- aldosterone system (RAAS). TDF also increased oxidative stress, as evidenced by higher TBARS and lower GSH levels, and induced dyslipidemia. Association of TDF and vitamin D deficiency aggravated renovascular effects and TDFinduced nephrotoxicity at least in part by the increase of oxidative stress and the involvement of RAAS. Hence, it is important to monitor vitamin D levels in HIV-infected patients treated with TDF

A Síndrome da Imunodeficiência Adquirida (AIDS) é um problema de saúde pública. O Tenofovir Disoproxil Fumarato (TDF) foi o primeiro inibidor do nucleotídeo da transcriptase reversa e é a droga mais recomendada para o tratamento da AIDS. Entretanto, o uso prolongado de TDF está associado com a nefrotoxicidade. A deficiência de vitamina D tem alta prevalência em indivíduos infectados com o Vírus da Imunodeficiência Humana (HIV). A vitamina D participa da regulação de atividades fisiológicas de diversos órgãos, incluindo o rim, oferecendo proteção contra as lesões ocasionadas por diferentes causas. Portanto, pacientes com níveis baixos de vitamina D infectados com o HIV podem apresentar complicações renais e cardiovasculares durante a terapia antirretroviral. Sendo assim, a carência desta vitamina pode acelerar a progressão da doença renal. Tendo em vista o aumento da incidência de hipovitaminose D na população mundial, esse trabalho tem o objetivo de verificar os mecanismos que levam ao desenvolvimento da lesão renal em ratos depletados de vitamina D submetidos ao tratamento com TDF. Ratos Wistar foram divididos em quatro grupos: controle, animais que receberam dieta padrão por 60 dias; dVD, animais que receberam dieta depletada em vitamina D por 60 dias; TDF, animais que receberam dieta padrão por 60 dias com a adição de TDF (50 mg/kg de dieta) nos últimos 30 dias; e dVD+TDF, animais que receberam dieta depletada em vitamina D por 60 dias com a adição de TDF nos últimos 30 dias. Ao final dos 60 dias, os animais foram submetidos à eutanásia, amostras de sangue, urina e o tecido renal foram coletados para a análise dos mecanismos de lesão renal. O tratamento com TDF levou a insuficiência renal observada pela queda da filtração glomerular e lesão tubular proximal com aparecimento de fosfatúria ocasionada pela diminuição do cotransportador sódio/fosfato subtipo IIa. Essas alterações foram acompanhadas de hipertensão e modificações no perfil lipídico. A deficiência em vitamina D associada à administração de TDF agravou os efeitos renovasculares e a nefrotoxicidade induzida pelo TDF, pelo menos em parte, devido ao aumento nos marcadores de estresse oxidativo e a participação do sistema renina-angiotensina-aldosterona. Portanto, é essencial monitorar os níveis de vitamina D em pacientes infectados com o HIV tratados com TDF / Acquired Immunodeficiency Syndrome (AIDS) has become one of the world\'s most serious health problem. Tenofovir Disoproxil Fumarate (TDF) was the first available nucleotidic reverse transcription inhibitor and is a widely prescribed antiretroviral medication for treatment of Human Immunodeficiency Virus (HIV). However, the long-term use of TDF has been associated with a number of toxicities, including those affecting the kidney. Vitamin D deficiency is prevalent among HIVinfected individuals. Vitamin D not only regulates numerous physiological activities of multiple organ systems, but also protects the kidney from injury from different causes. Thus, HIV-infected subjects with low levels of vitamin D could experience increased complications during antiretroviral therapy, such as cardiovascular disease and renal impairment. In view of the high worldwide incidence of hypovitaminosis D, the aim of this study was to investigate the effects of vitamin D deficiency on TDF-induced nephrotoxicity. Wistar rats were divided into four groups: control, receiving a standard diet for 60 days; dVD, receiving a vitamin D-free diet for 60 days; TDF, receiving a standard diet for 60 days with the addition of TDF (50 mg/kg food) for the last 30 days; and dVD+TDF receiving a vitamin D-free diet for 60 days with the addition of TDF for the last 30 days. At the end of the protocol, animals were euthanized and blood, urine and tissue samples were collected in order to evaluate the mechanisms responsible for renal injury. TDF led to impaired renal function, hyperphosphaturia, hypophosphatemia, hypertension and increased renal vascular resistance due to downregulation of the sodium-phosphorus cotransporter and upregulation of reninangiotensin- aldosterone system (RAAS). TDF also increased oxidative stress, as evidenced by higher TBARS and lower GSH levels, and induced dyslipidemia. Association of TDF and vitamin D deficiency aggravated renovascular effects and TDFinduced nephrotoxicity at least in part by the increase of oxidative stress and the involvement of RAAS. Hence, it is important to monitor vitamin D levels in HIV-infected patients treated with TDF

Na maioria dos países, a incidência e prevalência da doença renal crônica (DRC) vem aumentando ao longo dos anos. Embora tenha havido uma melhora significativa no manejo da DRC com os inibidores do sistema renina-angiotensina-aldosterona, a doença ainda é progressiva, levando a necessidade do surgimento de novas estratégias protetoras. A fibrose renal progressiva está presente na DRC e envolve a participação de várias citocinas, com destaque para o fator Transforming growth factor- beta1 (TGF-beta1). Tem sido demonstrado que a mortalidade de pacientes com DRC está diretamente relacionada à função renal e está associada a riscos tradicionais como cardiovasculares e infecções. Entretanto, esses riscos tradicionais explicam apenas metade das causas de mortalidade nesses pacientes. Evidências crescentes mostram que o status de vitamina D pode ser um fator de risco não tradicional para a evolução da DRC. Tendo em vista o importante papel da vitamina D na manutenção das funções fisiológicas essenciais e a observação da queda dos níveis deste hormônio na DRC, torna-se relevante o estudo da deficiência de vitamina D nos eventos envolvidos na evolução crônica da lesão renal aguda em modelo experimental de isquemia/reperfusão renal. Ratos Wistar foram divididos em quatro grupos: controle, animais que receberam dieta padrão; dVD, animais que receberam dieta depletada em vitamina D; Isq, animais que receberam dieta padrão e foram submetidos ao insulto de isquemia/reperfusão renal bilateral no 28º dia; Isq+dVD, animais que receberam dieta depletada em vitamina D e foram submetidos ao insulto de isquemia/reperfusão bilateral no 28º dia. Ao final dos 90 dias do protocolo, os animais foram submetidos à eutanásia, amostras de sangue, urina e o tecido renal foram coletados para a análise dos mecanismos de lesão renal. Os animais submetidos ao insulto de isquemia/reperfusão renal apresentaram hipertrofia renal, aumento dos níveis de pressão arterial média, colesterol e de PTH plasmático. Além disso, foi observada expansão da área intersticial, aumento do infiltrado de macrófagos/monócitos, da expressão de colágeno IV, fibronectina, vimentina e alfa-actina e redução da expressão da proteína Klotho. A deficiência de vitamina D contribuiu para a elevação dos níveis plasmáticos de PTH e aumento da proteinúria assim como para as alterações túbulo-intersticiais crônicas importantes (fibrose e infiltrado inflamatório do interstício, dilatação e atrofia tubular), aumento da expressão da citocina TGF-beta1 expressão do receptor de vitamina D (VDR) e da proteína Klotho, observados nos animais deficientes em vitamina D submetidos ao insulto de isquemia/reperfusão renal. Portanto, através de vias inflamatórias e com participação do fator de crescimento TGF-beta1 ê um fator agravante para o dano túbulo-intersticial e formação de fibrose intersticial nesse modelo experimental de isquemia/reperfusão renal / In most countries, the incidence and prevalence of chronic kidney disease (CKD) has been increasing over the years. Although there was a significant improvement in the management of CKD with renin-angiotensin-system inhibitors, the disease is still progressive, leading to the need of emergence of new protective strategies. The progressive renal fibrosis is present in CKD and involves the participation of several cytokines, especially the Transforming growth factor-beta1 (TGF-beta1). It has been shown that the mortality of patients with CKD is directly related to renal function, which is associated to traditional risk factors such as cardiovascular diseases and infections. However, these traditional risk factors explain only half of the causes of mortality in these patients. Growing evidence shows that vitamin D status may be a non-traditional risk factor for the progression of CKD. Considering the important role of vitamin D in the maintenance of essential physiological functions and the observation of low levels of this hormone in CKD, the study of vitamin D deficiency in the events involved in chronic evolution of acute kidney injury in an experimental model of ischemia/reperfusion becomes relevant. Wistar rats were divided into four groups : control, animals received a standard diet ; dVD, animals received a vitamin D-depleted diet ; Isq, animals received a standard diet and were subjected to bilateral renal ischemia/reperfusion injury on day 28; Isq +dVD, animals received a vitamin D-depleted diet and were subjected to bilateral renal ischemia/reperfusion injury on day 28 . At the end of the 90 days of the protocol, the animals were euthanized and samples of blood, urine and kidney tissue were collected for analysis of the mechanisms of renal injury. The animals subjected to the insult of ischemia/ reperfusion showed renal hypertrophy, increased levels of mean blood pressure, cholesterol and plasma PTH. Furthermore, expansion of the interstitial area, increased infiltration of macrophages/monocytes, increased expression of collagen IV, fibronectin, vimentin and alpha-actin, and reduced expression of Klotho protein were observed. The vitamin D deficiency contributed to the elevation of plasma PTH levels and increased proteinuria as well as for important chronic tubulo-interstitial changes (fibrosis and inflammatory infiltration of the interstitium, tubular dilation and atrophy), increased expression of cytokine TGF-beta1 vitamin D receptor (VDR) and Klotho protein observed in vitamin D-deficient animals subjected to the insult of renal ischemia/reperfusion. Therefore, through inflammatory pathways and involvement of TGF-beta1 w y aggravating factor in tubulointerstitial damage and formation of interstitial fibrosis in this experimental model of renal ischemia/reperfusion

Indiana University-Purdue University Indianapolis (IUPUI) / Multiple sclerosis (MS) is a disabling disease that afflicts an estimated two million people worldwide. The disease is characterized by degradation of the myelin sheath that insulates neurons of the central nervous system manifesting as a heterogeneous collection of symptoms. Two enzymes, protein arginine deaminases type 2 and 4 (PAD2 and PAD4) have been implicated to play an etiologic role in demyelination and neurodegeneration by catalyzing a post-translational modification of arginine peptide residues to citrulline. The pathogenesis of MS is poorly understood, though vitamin D deficiency is a well-associated risk factor for developing the disorder. Using the experimental autoimmune encephalomyelitis (EAE) model of MS we demonstrate vitamin D treatment to attenuate over-expression of PAD 2 and 4 in the brain and spine during EAE. In addition, we identify two molecules produced by peripheral immune cells, IFNɣ and IL-6, as candidate signaling molecules that induce PAD expression in the brain. We demonstrate vitamin D treatment to inhibit IFNɣ mediated up regulation of PAD2 and PAD4 both directly within the brain and by modulating PAD-inducing cytokine production by infiltrating immune cells. These results provide neuroprotective rational for the supplementation of vitamin D in MS patients. More importantly, these results imply an epigenetic link between vitamin D deficiency and the pathogenesis of MS that merits further investigation.