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1.
Biology (Basel) ; 13(8)2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39194567

RESUMEN

In this review, we summarize the processes of the assembly of multi-protein replisomes at the origins of replication. Replication licensing, the loading of inactive minichromosome maintenance double hexamers (dhMCM2-7) during the G1 phase, is followed by origin firing triggered by two serine-threonine kinases, Cdc7 (DDK) and CDK, leading to the assembly and activation of Cdc45/MCM2-7/GINS (CMG) helicases at the entry into the S phase and the formation of replisomes for bidirectional DNA synthesis. Biochemical and structural analyses of the recruitment of initiation or firing factors to the dhMCM2-7 for the formation of an active helicase and those of origin melting and DNA unwinding support the steric exclusion unwinding model of the CMG helicase.

2.
BMC Nephrol ; 25(1): 206, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918734

RESUMEN

BACKGROUND: Tubular biomarkers, which reflect tubular dysfunction or injury, are associated with incident chronic kidney disease and kidney function decline. Several tubular biomarkers have also been implicated in the progression of autosomal dominant polycystic kidney disease (ADPKD). We evaluated changes in multiple tubular biomarkers in four groups of patients with ADPKD who participated in one of two clinical trials (metformin therapy and diet-induced weight loss), based on evidence suggesting that such interventions could reduce tubule injury. METHODS: 66 participants (26 M/40 F) with ADPKD and an estimated glomerular filtration rate (eGFR) ≥ 30 ml/min/1.73m2 who participated in either a metformin clinical trial (n = 22 metformin; n = 23 placebo) or dietary weight loss study (n = 10 daily caloric restriction [DCR]; n = 11 intermittent fasting [IMF]) were included in assessments of urinary tubular biomarkers (kidney injury molecule-1 [KIM-1], fatty-acid binding protein [FABP], interleukin-18 [IL-18], monocyte chemoattractant protein-1 [MCP-1], neutrophil gelatinase-associated lipocalin [NGAL], clusterin, and human cartilage glycoprotein-40 [YKL-40]; normalized to urine creatinine), at baseline and 12 months. The association of baseline tubular biomarkers with both baseline and change in height-adjusted total kidney volume (HtTKV; percent change from baseline to 12 months) and estimated glomerular filtration rate (eGFR; absolute change at 12 months vs. baseline), with covariate adjustment, was also assessed using multiple linear regression. RESULTS: Mean ± s.d. age was 48 ± 8 years, eGFR was 71 ± 16 ml/min/1.73m2, and baseline BMI was 30.5 ± 5.9 kg/m2. None of the tubular biomarkers changed with any intervention as compared to placebo. Additionally, baseline tubular biomarkers were not associated with either baseline or change in eGFR or HtTKV over 12 months, after adjustments for demographics, group assignment, and clinical characteristics. CONCLUSIONS: Tubular biomarkers did not change with dietary-induced weight loss or metformin, nor did they associate with kidney disease progression, in this cohort of patients with ADPKD.


Asunto(s)
Biomarcadores , Restricción Calórica , Tasa de Filtración Glomerular , Túbulos Renales , Metformina , Riñón Poliquístico Autosómico Dominante , Humanos , Metformina/uso terapéutico , Riñón Poliquístico Autosómico Dominante/orina , Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Riñón Poliquístico Autosómico Dominante/dietoterapia , Masculino , Femenino , Biomarcadores/orina , Persona de Mediana Edad , Túbulos Renales/patología , Túbulos Renales/efectos de los fármacos , Adulto , Lipocalina 2/orina , Quimiocina CCL2/orina , Proteínas de Unión a Ácidos Grasos/orina , Receptor Celular 1 del Virus de la Hepatitis A/metabolismo , Receptor Celular 1 del Virus de la Hepatitis A/análisis , Proteína 1 Similar a Quitinasa-3/orina , Hipoglucemiantes/uso terapéutico
4.
Front Pediatr ; 12: 1399615, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38808102

RESUMEN

Objective: To systematically evaluate the effect of vitamin D deficiency during pregnancy on neonatal adverse outcomes, such as preterm infants, low birth weight infants (LBWI), and small for gestational age (SGA) infants. Methods: A comprehensive literature search was conducted across multiple databases including PubMed, Embase, Cochrane Library, SinoMed, Wanfang Data Knowledge Service Platform, China National Knowledge Internet (CNKI), and VIP Chinese Science and Technology Journal Database (VIP). Following predefined inclusion and exclusion criteria, two researchers independently screened, extracted data, and assessed the quality of the included studies. Meta-analysis was performed using RevMan 5.4 and Stata 14 software to synthesize the findings. Results: This study incorporated 13 cohort studies from 8 different countries and regions, encompassing a total of 55,162 pregnant women, among whom 28,155 were identified as having vitamin D deficiency. The Newcastle-Ottawa Scale (NOS) score ranged from 7-9 points. Meta-analysis results indicated a higher incidence of LBWI (OR = 5.52, 95% CI = 1.31-23.22. P = 0.02) in the group of pregnant women with vitamin D deficiency compared to those with adequate levels. However, there was no statistically significant difference in the likelihood of premature birth (OR = 1.25, 95% CI = 0.78-1.99. P = 0.36) or SGA (OR = 1.47, 95% CI = 0.81-2.68. P = 0.21) among newborns born to mothers with vitamin D deficiency vs. those with sufficient levels of vitamin D. Subgroup analysis based on the timing of maternal blood collection revealed that there was no statistically significant association between vitamin D levels during pregnancy and the incidence of preterm birth across all stages of pregnancy. Furthermore, vitamin D deficiency throughout the entire pregnancy was associated with an increased incidence of neonatal LBWI, whereas vitamin D levels during the first, second, and third trimesters did not demonstrate statistically differences on LBWI. Neonates born to mothers with vitamin D deficiency throughout pregnancy were found to have a higher likelihood of developing SGA. However, there was no statistically significant association between vitamin D levels and the development of SGA during the first and second trimesters. Conclusions: Adequate levels of vitamin D during pregnancy may decrease the incidence of LBWI, although further research is needed to determine its impact on the occurrence of preterm birth and SGA. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024535950, Identifier: (CRD42024535950).

6.
Contemp Clin Trials ; 137: 107423, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38151173

RESUMEN

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the development and continued growth of multiple cysts in the kidneys leading to ultimate loss of kidney function in most patients. Currently, tolvaptan is the only agency approved therapy to slow kidney disease advancement in patients with faster progressing disease underscoring the need for additional ADPKD therapies suitable for all patients. We previously showed that pravastatin slowed kidney disease progression in children and young adults with ADPKD. However, the intervention has not been tested in an adult cohort. AIMS: The aim of the study is to conduct a single center, randomized, placebo-controlled double-blinded clinical trial to determine the efficacy of pravastatin on slowing kidney disease progression in adult patients with early stage ADPKD. METHODS: One hundred and fifty adult patients with ADPKD and eGFR ≥60 ml/min/1.73m2 will be enrolled in the study and randomized to receive 40 mg/day pravastatin or placebo for a period of 2-years. OUTCOMES: The primary outcome of the trial is change in total kidney volume assessed by magnetic resonance imaging (MRI). Secondary outcomes include change in kidney function by iothalamate GFR and renal blood flow and markers of inflammation and oxidative stress. CONCLUSION: This study will assess the kidney therapeutic benefits of pravastatin in adult patients with ADPKD. The recruitment goal of 150 subjects was attained and the study is ongoing. REGISTRATION: This study is registered on Clinicaltrials.gov # NCT03273413.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Riñón Poliquístico Autosómico Dominante , Adulto Joven , Niño , Humanos , Adulto , Riñón Poliquístico Autosómico Dominante/diagnóstico por imagen , Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Riñón Poliquístico Autosómico Dominante/complicaciones , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Pravastatina/uso terapéutico , Método Doble Ciego , Progresión de la Enfermedad , Tasa de Filtración Glomerular
9.
J Am Soc Nephrol ; 34(8): 1433-1444, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37228030

RESUMEN

SIGNIFICANCE STATEMENT: Lower serum bicarbonate levels, even within the normal range, are strongly linked to risks of cardiovascular disease in CKD, possibly by modifying vascular function. In this randomized, controlled trial, treatment with sodium bicarbonate (NaHCO 3 ) did not improve vascular endothelial function or reduce arterial stiffness in participants with CKD stage 3b-4 with normal serum bicarbonate levels. In addition, NaHCO 3 treatment did not reduce left ventricular mass index. NaHCO 3 did increase plasma bicarbonate levels and urinary citrate excretion and reduce urinary ammonium excretion, indicating that the intervention was indeed effective. NaHCO 3 therapy was safe with no significant changes in BP, weight, or edema. These results do not support the use of NaHCO 3 for vascular dysfunction in participants with CKD. BACKGROUND: Lower serum bicarbonate levels, even within the normal range, are strongly linked to risks of cardiovascular disease in CKD, possibly by modifying vascular function. Prospective interventional trials with sodium bicarbonate (NaHCO 3 ) are lacking. METHODS: We conducted a randomized, double-blind, placebo-controlled trial examining the effect of NaHCO 3 on vascular function in 109 patients with CKD stage 3b-4 (eGFR 15-44 ml/min per 1.73 m 2 ) with normal serum bicarbonate levels (22-27 mEq/L). Participants were randomized 1:1 to NaHCO 3 or placebo at a dose of 0.5 mEq/lean body weight-kg per day for 12 months. The coprimary end points were change in brachial artery flow-mediated dilation (FMD) and change in aortic pulse wave velocity over 12 months. RESULTS: Ninety patients completed this study. After 12 months, plasma bicarbonate levels increased significantly in the NaHCO 3 group compared with placebo (mean [SD] difference between groups 1.35±2.1, P = 0.003). NaHCO 3 treatment did not result in a significant improvement in aortic pulse wave velocity from baseline. NaHCO 3 did result in a significant increase in flow-mediated dilation after 1 month; however, this effect disappeared at 6 and 12 months. NaHCO 3 resulted in a significant increase in 24-hour urine citrate and pH and a significant decrease in 24-hour urine ammonia. There was no significant change in left ventricular mass index, ejection fraction, or eGFR with NaHCO 3 . NaHCO 3 treatment was safe and well-tolerated with no significant changes in BP, antihypertensive medication, weight, plasma calcium, or potassium levels. CONCLUSION: Our results do not support the use of NaHCO 3 for vascular dysfunction in participants with CKD and normal serum bicarbonate levels.


Asunto(s)
Enfermedades Cardiovasculares , Insuficiencia Renal Crónica , Humanos , Bicarbonato de Sodio/uso terapéutico , Bicarbonatos , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Análisis de la Onda del Pulso , Estudios Prospectivos , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Método Doble Ciego
12.
Physiol Rep ; 10(22): e15490, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36394074

RESUMEN

Patients with chronic kidney disease (CKD) commonly experience sex hormone disturbances, which may be associated with the risk of cardiovascular disease (CVD) and mortality. This review aimed to systematically evaluate current findings on the association of sex hormone levels with the risk of CVD events and mortality (CVD and all-cause) in the CKD population. Articles were systematically searched in CINAHL, Cochrane, and PubMed. A total of 1739 articles were independently screened by two reviewers and 17 prospective cohort studies were included. The clinical conditions of the patients were those with non-dialysis CKD [mean/median estimated glomerular filtration rate (eGFR) between 15-51 ml/min/1.73 m2 ] and those on chronic dialysis (mean/median vintage between 6-125 months). The sample size ranged from 111 to 2419 and the mean/median age of subjects ranged from 52 to 72 years. The sex hormones studied were testosterone, estradiol, prolactin, dehydroepiandrosterone sulfate, and relaxin. A random-effects model was used to generate a pooled hazard ratio (HR) to evaluate the association of total testosterone levels with the risk of CVD and all-cause mortality. Most studies examined total testosterone levels (11 out of 17 studies) and studied only male patients (12 out of 17 studies). A lower total testosterone level was associated with a higher risk of CVD mortality [HR 4.37 (95% CI 1.40-13.65)] and all-cause mortality [1.96 (1.35-2.83)] in males with CKD. To conclude, there is a strong need for additional studies examining the association of sex hormones with cardiovascular and mortality risk in female patients with CKD.


Asunto(s)
Enfermedades Cardiovasculares , Insuficiencia Renal Crónica , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Enfermedades Cardiovasculares/etiología , Estudios Prospectivos , Factores de Riesgo , Insuficiencia Renal Crónica/complicaciones , Hormonas Esteroides Gonadales , Testosterona
13.
Front Physiol ; 13: 980783, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36187760

RESUMEN

Background: Cardiovascular disease (CVD) is the leading cause of death worldwide and aging is the primary risk factor for the development of CVD. The increased risk of CVD with aging is largely mediated by the development of vascular dysfunction. Excessive production of mitochondrial reactive oxygen species (mtROS) is a key mechanism of age-related vascular dysfunction. Therefore, establishing the efficacy of therapies to reduce mtROS to improve vascular function with aging is of high biomedical importance. Previously, in a small, randomized, crossover-design pilot clinical trial, our laboratory obtained initial evidence that chronic oral supplementation with the mitochondrial-targeted antioxidant MitoQ improves vascular function in healthy older adults. Here, we describe the protocol for an ongoing R01-funded phase IIa clinical trial to establish the efficacy of MitoQ as a therapy to improve vascular function in older adults (ClinicalTrials.gov Identifier: NCT04851288). Outcomes: The primary outcome of the study is nitric oxide (NO)-mediated endothelium-dependent dilation (EDD) as assessed by brachial artery flow-mediated dilation (FMDBA). Secondary outcomes include mtROS-mediated suppression of EDD, aortic stiffness as measured by carotid-femoral pulse wave velocity, carotid compliance and ß-stiffness index, and intima media thickness. Other outcomes include the assessment of endothelial mitochondrial health and oxidative stress in endothelial cells obtained by endovascular biopsy; the effect of altered circulating factors following MitoQ treatment on endothelial cell NO bioavailability and whole cell and mitochondrial reactive oxygen species production ex vivo; and circulating markers of oxidative stress, antioxidant status, and inflammation. Methods: We are conducting a randomized, placebo-controlled, double-blind, parallel group, phase IIa clinical trial in 90 (45/group) healthy older men and women 60 years of age or older. Participants complete baseline testing and are then randomized to either 3 months of oral MitoQ (20 mg; once daily) or placebo supplementation. Outcome measures are assessed at the midpoint of treatment, i.e., 6 weeks, and again at the conclusion of treatment. Discussion: This study is designed to establish the efficacy of chronic supplementation with the mitochondrial-targeted antioxidant MitoQ for improving vascular endothelial function and reducing large elastic artery stiffness in older adults, and to investigate the mechanisms by which MitoQ supplementation improves endothelial function.

14.
Kidney Int ; 102(6): 1331-1344, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36063874

RESUMEN

Complement activation at a particular location is determined by the balance of activating and inhibitory proteins. Factor H is a key regulator of the alternative pathway of complement, and genetic or acquired impairments in Factor H are associated with glomerular injury. The human Factor H-related proteins (FHRs) comprise a family of five proteins that are structurally related to Factor H. Variations in the genes or expression levels of the FHRs are also associated with glomerular disease, although the mechanisms of glomerular protection/injury are incompletely understood. To explore the role of the FHRs on complement regulation/dysregulation in the kidney, we expressed and purified recombinant murine FHRs (FHRs A, B, C and E). These four distinct FHRs contain binding regions with high amino acid sequence homology to binding regions within Factor H, but we observed different interactions of the FHRs with Factor H binding ligands, including heparin and C3d. There was differential binding of the FHRs to the resident kidney cell types (mesangial, glomerular endothelial, podocytes, and tubular epithelial). All four FHRs caused complement dysregulation on kidney cell surfaces in vitro, although the magnitude of the effect differed among the FHRs and also varied among the different kidney cells. However, only FHR E caused glomerular complement dysregulation when injected in vivo but did not exacerbate injury when injected into mice with ischemic acute kidney injury, an alternative pathway-mediated model. Thus, our experiments demonstrate that the FHRs have unique, and likely context-dependent, effects on the different cell types within the kidney.


Asunto(s)
Factor H de Complemento , Enfermedades Renales , Humanos , Ratones , Animales , Factor H de Complemento/genética , Factor H de Complemento/metabolismo , Activación de Complemento , Proteínas del Sistema Complemento/metabolismo , Riñón/metabolismo
15.
Front Physiol ; 13: 967478, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105300

RESUMEN

Background: High blood pressure (BP), particularly systolic BP (SBP), is the major modifiable risk factor for cardiovascular diseases and related disorders of aging. SBP increases markedly with aging in women such that the prevalence of above-normal SBP (i.e., ≥120 mmHg) in postmenopausal women exceeds rates in age-matched men. This increase in SBP is associated with vascular endothelial dysfunction, mediated by excessive reactive oxygen species-induced oxidative stress and consequent reductions in nitric oxide bioavailability. Moderate-intensity aerobic exercise is a recommended lifestyle strategy for reducing SBP. However, adherence to aerobic exercise guidelines among postmenopausal women is low (<30%) and aerobic exercise does not consistently enhance endothelial function in estrogen-deficient postmenopausal women. High-resistance inspiratory muscle strength training (IMST) is a time-efficient, adherable lifestyle intervention that involves inhaling against resistance through a handheld device (30 breaths/day). Here, we present the protocol for a randomized controlled trial investigating the efficacy of 3 months of high-resistance IMST compared to guideline-based, "standard-of-care" aerobic exercise training for decreasing SBP and improving endothelial function in estrogen-deficient postmenopausal women with above-normal SBP (120-159 mmHg) at baseline (ClinicalTrials.gov Identifier: NCT05000515). Methods: A randomized, single-blind, parallel-group design clinical trial will be conducted in 72 (36/group) estrogen-deficient postmenopausal women with above-normal SBP. Participants will complete baseline testing and then be randomized to either 3 months of high-resistance IMST (30 breaths/day, 6 days/week, 75% maximal inspiratory pressure) or moderate-intensity aerobic exercise training (brisk walking 25 min/day, 6 days/week, 40-60% heart rate reserve). Outcome measures will be assessed after 3 months of either intervention. Following end-intervention testing, participants will abstain from their assigned intervention for 6 weeks, after which BP and endothelial function will be assessed to evaluate the potential persistent effects of the intervention on the primary and secondary outcomes. Discussion: This study is designed to compare the effectiveness of time-efficient, high-resistance IMST to guideline-based aerobic exercise training for lowering SBP and improving endothelial function, and interrogating potential mechanisms of action, in estrogen-deficient postmenopausal women. Clinical Trial Registration: ClinicalTrials.gov, Identifier: NCT05000515.

16.
BMC Nephrol ; 23(1): 245, 2022 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-35810296

RESUMEN

BACKGROUND: Hyperphosphatemia is common in patients on peritoneal dialysis (PD). Restricting dietary phosphorus often leads to a decrease in protein intake, which may result in hypoalbuminemia. The high pill burden of phosphate binders may also contribute to compromised appetite and dietary intake. Hypoalbuminemia is associated with an increased risk of morbidity and mortality in PD patients. The goal of this study was to determine if sucroferric oxyhydroxide improves albumin and self-reported measures of appetite in PD patients. METHODS: We performed a prospective, open-label, 6-month, pilot study of 17 adult PD patients from the Denver Metro Area. Patients had to use automated peritoneal dialysis for ≥ 3 months, have a serum albumin ≤ 3.8 g/dL, and have serum phosphate ≥ 5.5 mg/dL or ≤ 5.5 mg/dL on a binder other than SO. SO was titrated to a goal serum phosphate of < 5.5 mg/dL. The primary outcome was change in serum phosphate, albumin, and phosphorus-attuned albumin (defined as albumin divided by phosphorus) over 6 months. RESULTS: The mean (SD) age and dialysis vintage was 55 ± 13 years and 3.8 ± 2.7 years, respectively. Participants' serum phosphate significantly decreased with fewer phosphate binder pills/day after switching to SO. There was no change in serum albumin, appetite, or dietary intake. However, participants had significant improvements in phosphorus-attuned albumin. CONCLUSION: The transition to SO improved phosphorus control, phosphorus-attuned albumin, and pill burden. There were no significant changes in self-reported appetite or dietary intake during the study. These findings suggest that PD patients maintained nutritional status with SO therapy. TRIAL REGISTRATION: First registered at ClinicalTrials.gov ( NCT04046263 ) on 06/08/2019.


Asunto(s)
Compuestos Férricos , Diálisis Peritoneal , Sacarosa , Adulto , Anciano , Combinación de Medicamentos , Compuestos Férricos/uso terapéutico , Humanos , Hiperfosfatemia/tratamiento farmacológico , Hiperfosfatemia/etiología , Hipoalbuminemia/tratamiento farmacológico , Hipoalbuminemia/etiología , Persona de Mediana Edad , Estado Nutricional , Diálisis Peritoneal/efectos adversos , Fosfatos , Fósforo , Proyectos Piloto , Estudios Prospectivos , Albúmina Sérica , Sacarosa/uso terapéutico
17.
Kidney360 ; 3(4): 657-665, 2022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35721602

RESUMEN

Background: Emerging evidence suggests an association of higher monocyte count and monocyte/lymphocyte ratio (MLR) with the risk of cardiovascular disease (CVD) in individuals without chronic kidney disease (CKD); however, limited studies have examined if this association translates to the CKD population. This study examined whether monocyte count and MLR are associated with the risk of CVD, CVD death, and all-cause death in patients with nondialysis CKD who participated in the Chronic Renal Insufficiency Cohort observational study. Methods: Baseline monocyte count and MLR were categorized into tertiles and also modeled continuously. Cox proportional hazards models were used to examine the association between monocyte count (primary predictor) and MLR (secondary predictor) at baseline and time to a composite of CVD events, including heart failure, myocardial infarction, ischemic stroke, and peripheral artery disease (primary outcome). Secondary outcomes were time to CVD death and all-cause death. Results: The median follow-up time was 9 years for CVD events and 11.7 years for death. In the fully adjusted model, participants with a higher monocyte count and MLR had a greater risk of CVD events (hazard ratio [HR] per doubling of monocyte count=1.2 [95% CI, 1.1 to 1.31]; HR per doubling of MLR=1.26 [95% CI, 1.16 to 1.36]), CVD death (HR=1.18 [95% CI, 0.99 to 1.41]; HR=1.27 [95% CI, 1.1 to 1.48]), and all-cause death (HR=1.17 [95% CI, 1.06 to 1.3]; HR=1.18 [95% CI, 1.09 to 1.29]). Conclusions: These results suggest that monocyte count and MLR may have the potential to be cost-effective, clinically available indicators of CVD risk in the CKD population.


Asunto(s)
Infarto del Miocardio , Insuficiencia Renal Crónica , Humanos , Recuento de Leucocitos , Linfocitos/metabolismo , Monocitos/metabolismo , Infarto del Miocardio/epidemiología , Insuficiencia Renal Crónica/complicaciones
18.
Front Cardiovasc Med ; 9: 881703, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35620522

RESUMEN

Background: Aging is the primary risk factor for cardiovascular diseases, the leading cause of death worldwide. Age-related increases in systolic blood pressure (SBP) link advancing age to cardiovascular disease risk. A key mechanism mediating the increase in SBP with aging is stiffening of the large elastic arteries, which occurs due to increases in oxidative stress, inflammation, and vascular smooth muscle tone. Nicotinamide adenine dinucleotide (NAD+) is a key molecule in energy metabolism and cellular functioning which declines with advancing age and chronic disease. Dietary supplementation with NAD+ precursors, such as nicotinamide riboside, boosts NAD+ bioavailability and may improve cardiovascular health. Here, we present the protocol for a randomized, controlled trial investigating the efficacy of 3 months of oral supplementation with nicotinamide riboside for decreasing SBP and arterial stiffness in midlife and older adults with initial above-normal (120-159 mmHg) SBP (ClinicalTrials.gov Identifier: NCT03821623). The primary outcome is casual (resting) SBP and secondary outcomes include 24-h SBP and aortic stiffness. Other outcomes include assessment of safety; tolerability; adherence; diastolic BP; systemic NAD+ bioavailability; and circulating biomarkers of oxidative stress, inflammation, and sympathoadrenal activity. Methods: A randomized, double-blind, placebo-controlled, single-site parallel-group design clinical trial will be conducted in 94 (47/group) midlife and older (age ≥ 50 years) adults with initial above-normal SBP. Participants will complete baseline testing and then will be randomized to either nicotinamide riboside (500 mg, 2×/day, NIAGEN®; ChromaDex Inc.) or placebo supplementation. Outcome measures will be assessed again after 3 months of treatment. Discussion: This study is designed to establish the safety and efficacy of the NAD+ boosting compound, nicotinamide riboside, for reducing casual and 24-h SBP and aortic stiffness in midlife and older adults with above-normal SBP at baseline, a population at increased risk of cardiovascular diseases. Clinical Trial Registration: [www.ClinicalTrials.gov], identifier [NCT03821623].

19.
Carcinogenesis ; 43(6): 557-570, 2022 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-35184170

RESUMEN

The factors (environmental and genetic) contributing to basal cell carcinoma (BCC) pathogenesis are well-established; however, effective agents for BCC prevention are marred by toxic side-effects. Herein, we assessed the efficacy of flavonolignan silibinin against ultraviolet B (UVB)-induced BCC in Ptch+/- (heterozygous patched homolog 1 gene) mouse model. Both male and female Ptch+/- mice were irradiated with a 240 mJ/cm2 UVB dose 3 times/week for 26 or 46 weeks, with or without topical application of silibinin (9 mg/200 µl in acetone, applied 30 min before or after UVB exposure). Results indicated that silibinin application either pre- or post-UVB exposure for 26 weeks significantly decreased the number of BCC lesions by 65% and 39% (P < 0.001 for both) and the area covered by BCCs (72% and 45%, P < 0.001 for both), respectively, compared to UVB alone. Furthermore, continuous UVB exposure for 46 weeks increased the BCC lesion number and the BCC area covered by ~6 and ~3.4 folds (P < 0.001), respectively. Notably, even in this 46 week prolonged UVB exposure, silibinin (irrespective of pre- or post-UVB treatment) significantly halted the growth of BCCs by 81-94% (P < 0.001) as well as other epidermal lesions; specifically, silibinin treated tissues had less epidermal dysplasia, fibrosarcoma, and squamous cell carcinoma. Immunohistochemistry and immunofluorescence studies revealed that silibinin significantly decreased basal cell proliferation (Ki-67) and the expression of cytokeratins (14 and 15), and Hedgehog signaling mediators Smo and Gli1 in the BCC lesions. Together, our findings demonstrate strong potential of silibinin to be efficacious in preventing the growth and progression of UVB-induced BCC.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Animales , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/prevención & control , Femenino , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Masculino , Ratones , Receptor Patched-1/genética , Silibina/farmacología , Silibina/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/prevención & control , Rayos Ultravioleta/efectos adversos
20.
iScience ; 25(1): 103697, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35059607

RESUMEN

Progression of autosomal dominant polycystic kidney disease (ADPKD) is modified by metabolic defects and obesity. Indeed, reduced food intake slows cyst growth in preclinical rodent studies. Here, we demonstrate the feasibility of daily caloric restriction (DCR) and intermittent fasting (IMF) in a cohort of overweight or obese patients with ADPKD. Clinically significant weight loss occurred with both DCR and IMF; however, weight loss was greater and adherence and tolerability were better with DCR. Further, slowed kidney growth correlated with body weight and visceral adiposity loss independent of dietary regimen. Similarly, we compared the therapeutic efficacy of DCR, IMF, and time restricted feeding (TRF) using an orthologous ADPKD mouse model. Only ADPKD animals on DCR lost significant weight and showed slowed cyst growth compared to ad libitum, IMF, or TRF feeding. Collectively, this supports therapeutic feasibility of caloric restriction in ADPKD, with potential efficacy benefits driven by weight loss.

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