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1.  No independent association of serum phosphorus with risk for death or progression to end-stage renal disease in a large screen for chronic kidney disease 
Kidney international  2013;84(5):989-997.
Whether higher serum phosphorus levels are associated with a higher risk for death and/or progression of chronic kidney disease (CKD) is not well established, and whether the association is confounded by access and barriers to care is unknown. To answer these questions, data of 10,672 individuals identified to have CKD (estimated glomerular filtration rate <60 ml/min per 1.73 m2) from those participating in a community-based screening program were analyzed. Over a median follow-up of 2.3 years, there was no association between quartiles of serum phosphorus and all-cause mortality (adjusted hazards ratio for serum phosphorus over 3.3 to 3.7, over 3.7 to 4.1, and over 4.1 mg/dl, respectively: 1.22 (0.95–1.56), 1.00 (0.76–1.32), and 1.00 (0.75–1.33); reference, serum phosphorus of 3.3 mg/dl and below). Individuals in the highest quartile for serum phosphorus had a significantly higher risk for progression to end-stage renal disease (ESRD) (unadjusted hazards ratio, 6.72 (4.16–10.85)); however, the risk became nonsignificant on adjustment for potential confounders. There was no appreciable change in hazards ratio with inclusion of variables related to access and barriers to care. Additional analyses in subgroups based on 12 different variables yielded similar negative associations. Thus, in the largest cohort of individuals with early-stage CKD to date, we could not validate an independent association of serum phosphorus with risk for death or progression to ESRD.
doi:10.1038/ki.2013.145
PMCID: PMC4103660  PMID: 23615501
barrier to care; cardiovascular disease; chronic kidney disease; end-stage renal disease; mortality; phosphorus
2.  Renin Inhibition and AT1R blockade improve metabolic signaling, oxidant stress and myocardial tissue remodeling 
Objective
Strategies that block angiotensin II actions on its angiotensin type 1 receptor or inhibit actions of aldosterone have been shown to reduce myocardial hypertrophy and interstitial fibrosis in states of insulin resistance. Thereby, we sought to determine if combination of direct renin inhibition with angiotensin type 1 receptor blockade in vivo, through greater reductions in systolic blood pressure (SBP) and aldosterone would attenuate left ventricular hypertrophy and interstitial fibrosis to a greater extent than either intervention alone.
Materials/Methods
We utilized the transgenic Ren2 rat which manifests increased tissue expression of murine renin which, in turn, results in increased renin-angiotensin system activity, aldosterone secretion and insulin resistance. Ren2 rats were treated with aliskiren, valsartan, the combination (aliskiren+valsartan), or vehicle for 21 days.
Results
Compared to Sprague-Dawley controls, Ren2 rats displayed increased systolic blood pressure, elevated serum aldosterone levels, cardiac tissue hypertrophy, interstitial fibrosis and ultrastructural remodeling. These biochemical and functional alterations were accompanied by increases in the NADPH oxidase subunit Nox2 and 3-nitrotyrosine content along with increases in mammalian target of rapamycin and reductions in protein kinase B phosphorylation. Combination therapy contributed to greater reductions in systolic blood pressure and serum aldosterone but did not result in greater improvement in metabolic signaling or markers of oxidative stress, fibrosis or hypertrophy beyond either intervention alone.
Conclusions
Thereby, our data suggest that the greater impact of combination therapy on reductions in aldosterone does not translate into greater reductions in myocardial fibrosis or hypertrophy in this transgenic model of tissue renin overexpression.
doi:10.1016/j.metabol.2012.12.012
PMCID: PMC3640616  PMID: 23352204
Direct Renin Inhibition; Angiotensin II Type 1 receptor; Echocardiography; Ren2 rat
3.  Type 2 diabetes in older people; the importance of blood pressure control 
Diabetes and hypertension often coexist and their coexistence substantially promote cardiovascular disease (CVD) and chronic kidney disease. Control of blood pressure to a level of 140/90 mm Hg in people with diabetes can prevent or at least delay CVD and chronic kidney disease.. In the past many society treatment guidelines have stressed tight blood pressure control (=< 130/80) for people with diabetes. But recommendations for such tight blood pressure control have not been supported by recent large randomized control trials, especially in in elderly. Here we review the recent literature regarding the benefits of blood pressure control in elderly patients with diabetics. We further focus on evidence for specific levels of blood pressure treatment goals, in this population subset..
doi:10.1007/s12170-013-0301-5
PMCID: PMC3647695  PMID: 23667714
Diabetes; Hypertension; Diabetes complications; Blood pressure control
5.  Therapy of obese patient with Cardiovascular Disease 
Current opinion in pharmacology  2013;13(2):200-204.
Obesity has reached epidemic proportions and is a significant public health concern. Obesity is associated with increased diabetes, cardiovascular and kidney disease, and associated morbidity and mortality. Despite the increasing public health problem of obesity, there is a dearth of effective treatment options. Following the FDA mandated withdrawal of sibutramine, the treatment options for obesity were limited to orlistat as the only pharmacological treatment option for long term management of obesity. Recently two new medications (Belviq and Qsymia) were approved by FDA for long term management of obesity. Many other anti-obesity drugs are under development. Bariatric surgery has been shown to be effective in the treatment of obesity and its comorbidities. The available data suggests that even modest weight loss improves diabetes and cardiovascular disease (CVD) risk factors. We summarize the treatment options for obesity and the efficacy of these options in ameliorating cardiovascular risk factors. We also focus on the recently approved anti-obesity drugs.
doi:10.1016/j.coph.2012.12.006
PMCID: PMC3648585  PMID: 23332347
6.  Metabolic impact of adding a thiazide diuretic to captopril 
Hypertension  2013;61(4):765-766.
doi:10.1161/HYPERTENSIONAHA.111.00494
PMCID: PMC3676883  PMID: 23424231
7.  Salt Loading Promotes Kidney Injury via Fibrosis in Young Female Ren2 Rats 
Cardiorenal Medicine  2014;4(1):43-52.
Background/Aims
It is increasingly recognized that there is sexual dimorphism in kidney disease progression; however, this disparity is lost in the presence of diabetes where women progress at a similar rate to men. The renin-angiotensin-aldosterone system (RAAS) is known to regulate diabetes-induced kidney injury, and recent literature would suggest that gender differences exist in RAAS-dependent responses in the kidney. In this regard, these gender differences may be overcome by excessive salt intake. Thereby, we hypothesized that salt would promote proteinuria in transgenic female rats under conditions of excess tissue angiotensin (Ang) II and circulating aldosterone.
Materials and Methods
We utilized young female transgenic (mRen2)27 (Ren2) rats and Sprague-Dawley (SD) littermates and fed a high-salt diet (4%) over 3 weeks.
Results
Compared to SD and Ren2 controls, female Ren2 rats fed a high-salt diet displayed increases in proteinuria, periarterial and interstitial fibrosis as well as ultrastructural evidence of basement membrane thickening, loss of mitochondrial elongation, mitochondrial fragmentation and attenuation of basilar canalicular infoldings. These findings occurred temporally with increases in transforming growth factor-β but not indices of oxidant stress.
Conclusions
Our current data suggest that a diet high in salt promotes progressive kidney injury as measured by proteinuria and fibrosis associated with transforming growth factor-β under conditions of excess tissue Ang II and circulating aldosterone.
doi:10.1159/000360866
PMCID: PMC4025048  PMID: 24847333
Angiotensin II; Transgenic (mRen2)27 rat; Proteinuria; Fibrosis; Reactive oxygen species

8.  Meal frequency differentially alters postprandial triacylglycerol and insulin concentrations in obese women 
Obesity (Silver Spring, Md.)  2013;21(1):10.1002/oby.20247.
The aim of this study was to compare postprandial lipemia, oxidative stress, antioxidant activity, and insulinemia between a three and six isocaloric high carbohydrate meal frequency pattern in obese women. In a counterbalanced order eight obese women completed two, 12 h conditions in which they consumed 1500 calories (14% protein, 21% fat, and 65% carbohydrate) either as three 500 calorie liquid meals every 4 h or six 250 calorie liquid meals every 2 h. Blood samples were taken every 30 min and analyzed for triacylglycerol (TAG), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, oxidized low-density lipoprotein cholesterol, myeloperoxidase, paraoxonase-1 activity, and insulin. The TAG incremental area under the curve (iAUC) during the three meal condition (321 ± 129 mg/dL·12 h) was significantly lower (P = 0.04) compared to the six meal condition (481 ± 155 mg/dL·12 h). The insulin iAUC during the three meal condition (5,549 ± 1,007 pmol/L·12 h) was significantly higher (P = 0.05) compared to the six meal condition (4,230 ± 757 pmol/L·12 h). Meal frequency had no influence on the other biochemical variables. Collectively, a three and six isocaloric high carbohydrate meal frequency pattern differentially alters postprandial TAG and insulin concentrations but has no effect on postprandial cholesterol, oxidative stress, or antioxidant activity in obese women.
doi:10.1002/oby.20247
PMCID: PMC3484202  PMID: 23505176
9.  Association Between Lack of Health Insurance and Risk of Death and ESRD: Results From the Kidney Early Evaluation Program (KEEP) 
Background
Uninsured adults in the United States have poor access to health care services and worse health outcomes than insured adults. Little is known about the association between lack of insurance and chronic kidney disease (CKD) progression to end-stage renal disease (ESRD) or death in patients at high risk of kidney disease. We used 2000–2011 data from the National Kidney Foundation’s Kidney Early Evaluation Program (KEEP) to examine this association.
Methods
The study population included KEEP participants younger than 65 years. Outcomes were time to ESRD (chronic kidney failure treated by renal replacement therapy) and time to death. Incident ESRD was ascertained by linkage to the US Renal Data System, and vital status, by linkage to the Social Security Administration Death Master File. We used Cox proportional hazard regression to examine the association between insurance and risk of death or ESRD after adjusting for demographic variables.
Results
Of 86,588 participants, 27.8% had no form of insurance, 10.3% had public insurance, and 61.9% had private insurance; 15.0% had CKD (defined as estimated glomerular filtration rate <60 mL/min/1.73 m2 or urine albumin-creatinine ratio ≥30 mg/g), 63.3% had hypertension, and 27.7% had diabetes. Of participants with CKD, 29.3% had no health insurance. Participants without insurance were younger, more likely to be Hispanic and to have 12 or fewer years of education, and less likely to have seen a physician in the past year. After adjustment for demographic characteristics, uninsured KEEP participants were 82% more likely than privately insured participants to die (HR, 1.82; 95% CI, 1.56–2.12; P < 0.001) and 72% more likely to develop ESRD (HR, 1.72; 95% CI, 1.33–2.22; P < 0.001). The association between insurance and outcomes varied by CKD stage.
Conclusions
Lack of insurance is an independent risk factor for early death and ESRD in this population at high risk of kidney disease. Considering the high morbidity and mortality and increasing cost associated with ESRD, access to appropriate health insurance coverage is warranted.
doi:10.1053/j.ajkd.2012.12.015
PMCID: PMC3739048  PMID: 23507267
Chronic kidney disease; end-stage renal disease; health insurance; mortality; public health
10.  Awareness of Kidney Disease and Relationship to End-Stage Renal Disease and Mortality 
The American Journal of Medicine  2012;125(7):661-669.
Background
Patients with chronic kidney disease are often reported to be unaware. We prospectively evaluated the association between awareness of kidney disease to end-stage renal disease and mortality.
Methods
We utilized 2000–2009 data from the National Kidney Foundation-Kidney Early Evaluation Program (KEEP™). Mortality was determined by cross reference to the Social Security Administration Death Master File, and development of end-stage by cross reference with the United States Renal Data System.
Results
Of 109,285 participants, 28,244 (26%) had chronic kidney disease defined by albuminuria or eGFR <60ml/min/1.73m2. Only 9% (n=2660) reported being aware of kidney disease. Compared to those who were not aware, participants aware of chronic kidney disease had lower eGFR (49 vs 62ml/min/1.73m2) and a higher prevalence of albuminuria (52 vs 46%), diabetes (47 vs 42%), cardiovascular disease (43 vs 28%) and cancer (23 vs 14%). Over 8.5 years of follow-up, aware participants compared to those unaware had a lower rate of survival for end-stage (83% and 96%) and mortality (78 vs 81%), p<0.001 respectively. After adjustment for demographics, socioeconomic factors, comorbidity, and severity of kidney disease, aware participants continued to demonstrate an increased risk for end-stage renal disease [hazard ratio (95% CI) 1.37(1.07–1.75); p<0.0123] and mortality [1.27(1.07–1.52); p<0.0077] relative to unaware participants with chronic kidney disease.
Conclusions
Among persons identified as having chronic kidney disease at a health screening, only a small proportion had been made aware of their diagnosis previously by clinicians. This subgroup was at a disproportionately high risk for mortality and end-stage renal disease.
doi:10.1016/j.amjmed.2011.11.026
PMCID: PMC3383388  PMID: 22626510
KEEP; CKD; awareness; ESRD; mortality
11.  Access to Health Care Among Adults Evaluated for CKD: Findings From the Kidney Early Evaluation Program (KEEP) 
Background
Data are scant regarding access to health care in patients with chronic kidney disease (CKD). We performed descriptive analyses using data from the National Kidney Foundation’s Kidney Early Evaluation Program (KEEP), a nationwide health screening program for adults at high risk of CKD.
Methods
From 2000–2010, a total of 122,502 adults without end-stage renal disease completed KEEP screenings; 27,927 (22.8%) met criteria for CKD (10,082, stages 1–2; 16,684, stage 3; and 1,161, stages 4–5). CKD awareness, self-rated health status, frequency of physician visits, difficulty obtaining medical care, types of caregivers, insurance status, and medication coverage and estimated costs were assessed.
Results
Participants with CKD were more likely to report fair/poor health status than those without CKD. Health care utilization increased at later CKD stages; ~95% of participants at stages 3–5 had visited a physician during the preceding year compared with 83.7% of participants without CKD. More Hispanic and African American than white participants at all CKD stages reported not having a physician. Approximately 40% of participants younger than 65 years reported fair/poor health status at stages 4–5 compared with ~30% who were 65 years and older. Younger participants at all stages were more likely to report extreme or somewhat/moderate difficulty obtaining medical care. Comorbid conditions (diabetes, hypertension, and prior cardiovascular events) were associated with increased utilization of care. Utilization of nephrology care was poor at all CKD stages; <6% of participants at stage 3 and <30% at stages 4–5 reported ever seeing a nephrologist.
Conclusions
Lack of health insurance and perceived difficulty obtaining medical care with lower health care utilization, both of which are consistent with inadequate access to health care, are more likely for KEEP participants who are younger than 65 years, nonwhite, and without previously diagnosed comorbid conditions. Nephrology care is infrequent in elderly participants with advanced CKD who are nonwhite, have comorbid disease, and have high-risk states for cardiovascular disease.
doi:10.1053/j.ajkd.2011.10.043
PMCID: PMC3694584  PMID: 22339901
Chronic kidney disease; health care access; health insurance; medication payment; socioeconomic status; educational status
12.  Combination Direct Renin Inhibition with Angiotensin Type 1 Receptor Blockade improves Aldosterone but does not improve Kidney Injury in the Transgenic Ren2 rat 
Regulatory Peptides  2012;176(1-3):36-44.
Enhanced renin-angiotensin-aldosterone system (RAAS) activation contributes to proteinuria and chronic kidney disease by increasing glomerular and tubulointerstitial oxidative stress, promotion of fibrosis. Renin activation is the rate limiting step in angiotensin (Ang II) and aldosterone generation, and recent work suggests direct renin inhibition improves proteinuria comparable to that seen with Ang type 1 receptor (AT1R) blockade. This is important as, even with contemporary use of AT1R blockade, the burden of kidney disease remains high. Thereby, we sought to determine if combination direct renin inhibition with AT1R blockade in vivo, via greater attenuation of kidney oxidative stress, would attenuate glomerular and proximal tubule injury to a greater extent than either intervention alone. We utilized the transgenic Ren2 rat with increased tissue RAS activity and higher serum levels of aldosterone, which manifests hypertension and proteinuria. Ren2 rats were treated with renin inhibition (aliskiren), AT1R blockade (valsartan), the combination (aliskiren+valsartan), or vehicle for 21 days. Compared to Sprague-Dawley controls, Ren2 rats displayed increased systolic pressure (SBP), circulating aldosterone, proteinuria and greater urine levels of the proximal tubule protein excretory marker beta-N-acetylglucosaminidase (β-NAG). These functional and biochemical alterations were accompanied by increases in kidney tissue NADPH oxidase subunit Rac1 and 3-nitrotyrosine (3-NT) content as well as fibronectin and collagen type III. These findings occurred in conjunction with reductions in the podocyte-specific protein podocin as well as the proximal tubule-specific megalin. Further, in transgenic animals there was increased tubulointerstitial fibrosis on light microscopy as well as ultrastructural findings of glomerular podocyte foot-process effacement and reduced tubular apical endosomal/lysosomal activity. Combination therapy led to greater reductions in SBP and serum aldosterone, but did not result in greater improvement in markers of glomerular and tubular injury (ie. β-NAG) compared to either intervention alone. Further, combination therapy did not improve markers of oxidative stress and podocyte and proximal tubule integrity in this transgenic model of RAAS-mediated kidney damage despite greater reductions in serum aldosterone and BP levels.
doi:10.1016/j.regpep.2012.03.002
PMCID: PMC3348429  PMID: 22465166
Aldosterone; Combination; Renin inhibition; AT1R blockade; Podocyte; β-NAG; Oxidative Stress
13.  The Association between Parathyroid Hormone Levels and Hemoglobin in Diabetic and Nondiabetic Participants in the National Kidney Foundation's Kidney Early Evaluation Program 
Cardiorenal Medicine  2013;3(2):120-127.
Background
Both anemia and secondary hyperparathyroidism are reflections of hormonal failure in chronic kidney disease (CKD). While the association of elevated levels of parathyroid hormone (PTH) and anemia has been studied among those with advanced CKD, less is known about this association in mild-to-moderate CKD.
Methods
In a cross-sectional analysis, the relationship between PTH and hemoglobin levels was investigated in 10,750 participants in the National Kidney Foundation's Kidney Early Evaluation Program with an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2.
Results
In the unadjusted analysis, higher PTH levels were associated with lower hemoglobin levels. However, after multivariable adjustment for age, race, gender, smoking status, education, cardiovascular disease, diabetes, hypertension, cancer, albuminuria, BMI, baseline eGFR, calcium, and phosphorus, the direction of association changed. As compared to the first PTH quintile, hemoglobin levels were 0.09 g/dl (95% CI: 0.01-0.18), 0.15 g/dl (95% CI: 0.07-0.24), 0.18 g/dl (95% CI: 0.09-0.26), and 0.13 g/dl (95% CI: 0.07-0.25) higher for the second, third, fourth, and fifth quintiles, respectively. Similarly, each standard deviation increase in natural log transformed PTH was associated with a 0.06 g/dl (95% CI: 0.03-0.09, p = 0.0003) increase in hemoglobin. However, a significant effect modification was seen for diabetes (p = 0.0003). Each standard deviation increase in natural log transformed PTH was associated with a 0.10 g/dl (95% CI: 0.054-0.138, p < 0.0001) increase in hemoglobin, while no association was seen among those without diabetes mellitus.
Conclusion
After multivariable adjustment, there was a small positive association between PTH and hemoglobin among diabetics but not among nondiabetics.
doi:10.1159/000351229
PMCID: PMC3721130  PMID: 23922552
Chronic kidney disease; Anemia; Secondary hyperparathyroidism

14.  Physician Utilization, Risk-Factor Control, and CKD Progression Among Participants in the Kidney Early Evaluation Program (KEEP) 
Background
Chronic kidney disease (CKD) is a well-known risk factor for cardiovascular mortality, but little is known about the association between physician utilization and cardiovascular disease risk-factor control in patients with CKD. We used 2005–2010 data from the National Kidney Foundation’s Kidney Early Evaluation Program (KEEP) to examine this association at first and subsequent screenings.
Methods
Control of risk factors was defined as control of blood pressure, glycemia, and cholesterol levels. We used multinomial logistic regression to examine the association between participant characteristics and seeing a nephrologist after adjusting for kidney function and paired t tests or McNemar tests to compare characteristics at first and second screenings.
Results
Of 90,009 participants, 61.3% had a primary care physician only, 2.9% had seen a nephrologist, and 15.3% had seen another specialist. The presence of 3 risk factors (hypertension, diabetes, and hypercholesterolemia) increased from 26.8% in participants with CKD stages 1–2 to 31.9% in those with stages 4–5. Target levels of all risk factors were achieved in 7.2% of participants without a physician, 8.3% of those with a primary care physician only, 9.9% of those with a nephrologist, and 10.3% of those with another specialist. Of up to 7,025 participants who met at least one criterion for nephrology consultation at first screening, only 12.3% reported seeing a nephrologist. Insurance coverage was associated strongly with seeing a nephrologist. Of participants who met criteria for nephrology consultation, 406 (5.8%) returned for a second screening, of whom 19.7% saw a nephrologist. The percentage of participants with all risk factors controlled was higher at the second screening (20.9% vs 13.3%).
Conclusion
Control of cardiovascular risk factors is poor in the KEEP population. The percentage of participants seeing a nephrologist is low, although better after the first screening. Identifying communication barriers between nephrologists and primary care physicians may be a new focus for KEEP.
doi:10.1053/j.ajkd.2011.11.019
PMCID: PMC3654535  PMID: 22339899
Cardiovascular disease risk factors; chronic kidney disease; nephrologist care; primary care
15.  Obesity, Diabetes, the Cardiorenal Syndrome, and Risk for Cancer 
Cardiorenal Medicine  2012;2(2):143-162.
Numerous epidemiological studies confirm that the prevalence of obesity and the cardiorenal metabolic syndrome (CRS) is extraordinarily high and that the rates have increased dramatically in the last three decades. In addition, epidemiological data demonstrate that obesity, the CRS, and diabetes are inextricably linked and are all associated with an increased incidence of a number of solid tissue cancers. The mechanisms for this association have been examined, including, but not limited to, higher levels of insulin and free levels of insulin-like growth factor and insulin resistance in obesity and the CRS. Mortality, morbidity, and the associated health care costs which are the link between obesity, the CRS, and diabetes are just beginning to be examined. In addition, we review the advantages of implementing lifestyle and surgical changes to modify obesity, lessening the development of the CRS, diabetes, and associated cancers. Epidemiological data regarding the general mechanisms of the pathogenesis of cancers associated with obesity, the CRS, and diabetes (specifically colon, pancreas, esophageal, liver, breast, prostate, thyroid, and renal carcinomas) are reviewed. The mechanisms by which obesity and other components of the CRS contribute to the pathogenesis of these cancers, such as hormone alterations and insulin- and insulin-like growth factor-dependent pathways of tumor pathogenesis, include the attending roles of inflammation and oxidative stress. Emphasis has been placed on obesity as a modifiable risk factor which, when addressed, provides a reduction in the rate of cancer deaths. In a second part to be published in the next issue of this journal, the relationship between diabetes and cancer will be reviewed in detail.
doi:10.1159/000337314
PMCID: PMC3376338  PMID: 22851963
Insulin resistance; Cancer; Inflammation; Oxidative stress
16.  DPP-4 Inhibitors as Therapeutic Modulators of Immune Cell Function and Associated Cardiovascular and Renal Insulin Resistance in Obesity and Diabetes 
Cardiorenal Medicine  2013;3(1):48-56.
The prevalence of obesity and diabetes continues to rise in the United States and worldwide. These findings parallel the expansion of childhood obesity and diabetes. Obesity is a central component of the cardiorenal metabolic syndrome (CRS) which increases the risk for cardiovascular disease (CVD) and chronic kidney disease (CKD). The hallmark of obesity, CRS, and early type 2 diabetes is insulin resistance, a result of decreased insulin metabolic signaling due, in part, to enhanced serine phosphorylation and/or proteasome-mediated degradation of the insulin receptor substrate. Cardiovascular and renal insulin resistance significantly contributes to endothelial dysfunction, impaired cardiac diastolic and vascular relaxation, glomerular injury, and tubular dysfunction. In this context, multiple factors including oxidative stress, increased inflammation, and inappropriate activation of the renin-angiotensin-aldosterone and the sympathetic nervous system contribute to overweight- and obesity-induced systemic and tissue insulin resistance. One common link between obesity and the development of insulin resistance appears to be a low-grade inflammatory response resulting from dysfunctional innate and adaptive immunity. In this regard, there has been recent work on the role of dipeptidyl peptidase-4 (DPP-4) in modulating innate and adaptive immunity. The direct effects of DPP-4 on immune cells and the indirect effects through GLP-1-dependent and -independent pathways suggest effects of DPP-4 inhibition may have beneficial effects beyond glycemic control in improving CVD and renal outcomes. Accordingly, this review addresses new insights into the role of DPP-4 in immune modulation and the potential beneficial effects of DPP-4 inhibitors in insulin resistance and associated CVD and CKD prevention.
doi:10.1159/000348756
PMCID: PMC3743398  PMID: 23946724
DPP-4; Cardiorenal syndrome; Obesity; Diabetes; Insulin resistance

19.  Mineralocorticoid Receptor-Dependent Proximal Tubule Injury Is Mediated by a Redox-Sensitive mTOR/S6K1 Pathway 
American Journal of Nephrology  2011;35(1):90-100.
Background/Aims
The mammalian target of rapamycin (mTOR) is a serine kinase that regulates phosphorylation (p) of its target ribosomal S6 kinase (S6K1), whose activation can lead to glomerular and proximal tubular cell (PTC) injury and associated proteinuria. Increased mTOR/S6K1 signaling regulates signaling pathways that target fibrosis through adherens junctions. Recent data indicate aldosterone signaling through the mineralocorticoid receptor (MR) can activate the mTOR pathway. Further, antagonism of the MR has beneficial effects on proteinuria that occur independent of hemodynamics.
Methods
Accordingly, hypertensive transgenic TG(mRen2)27 (Ren2) rats, with elevated serum aldosterone and proteinuria, and age-matched Sprague-Dawley rats were treated with either a low dose (1 mg/kg/day) or a conventional dose (30 mg/kg/day) of spironolactone (MR antagonist) or placebo for 3 weeks.
Results
Ren2 rats displayed increases in urine levels of the PTC brush border lysosomal enzyme N-acetyl-β-aminoglycosidase (β-NAG) in conjunction with reductions in PTC megalin, the apical membrane adherens protein T-cadherin and basolateral α-(E)-catenin, and fibrosis. In concert with these abnormalities, Ren2 renal cortical tissue also displayed increased Ser2448 (p)/activation of mTOR and Thr389 (p)-S6K1 and increased 3-nitrotyrosine (3-NT) content, a marker for peroxynitrite. Low-dose spironolactone had no effect on blood pressure but decreased proteinuria and β-NAG comparable to a conventional dose of this MR antagonist. Both doses of spironolactone attenuated ultrastructural maladaptive alterations and led to comparable reductions in (p)-mTOR/(p)-S6K1, 3-NT, fibrosis, and increased expression of α-(E)-catenin, T- and N-cadherin.
Conclusions
Thereby, MR antagonism improves proximal tubule integrity by targeting mTOR/S6K1 signaling and redox status independent of changes in blood pressure.
doi:10.1159/000335079
PMCID: PMC3316484  PMID: 22205374
Cadherin; Megalin; β-NAG; Proteinuria
20.  Nebivolol Improves Insulin Sensitivity in the TGR(Ren2)27 Rat 
Metabolism: clinical and experimental  2011;60(12):1757-1766.
Objective
Hypertension is often associated with increased oxidative stress and systemic insulin resistance. Use of β adrenergic receptor blockers in hypertension is limited due to potential negative influence on insulin sensitivity and glucose homeostasis. We sought to determine the impact of nebivolol, a selective vasodilatory β1adrenergic blocker, on whole-body insulin sensitivity, skeletal muscle oxidative stress, insulin signaling and glucose transport in the transgenic TG(mRen2)27rat (Ren2). This rodent model manifests increased tissue renin angiotensin expression, excess oxidative stress, and whole-body insulin resistance.
Research design and methods
Young (age 6-9 wks) Ren2 and age-matched Sprague-Dawley control rats were treated with nebivolol 10 mg/kg/day or placebo for 21 days. Basal measurements were obtained for glucose and insulin to calculate the Homeostasis Model Assessment (HOMA–IR). Additionally, insulin metabolic signaling, NADPH oxidase activity, reactive oxygen species (ROS), and ultrastructural changes as evaluated by transmission electron microscopy were examined ex vivo in skeletal muscle tissue.
Results
The Ren2 rat demonstrated systemic insulin resistance as examined by HOMA-IR, along with impaired insulin metabolic signaling in skeletal muscle. This was associated with increased oxidative stress and mitochondrial remodeling. Treatment with nebivolol was associated with improvement in insulin resistance and decreased NADPH oxidase activity/levels ROS in skeletal muscle tissue.
Conclusions
Nebivolol treatment for 3 weeks reduces NADPH oxidase activity and improves systemic insulin resistance, in concert with reduced oxidative stress in skeletal muscle in a young rodent model of hypertension, insulin resistance and enhanced tissue RAS expression.
doi:10.1016/j.metabol.2011.04.009
PMCID: PMC3170670  PMID: 21640361
Insulin resistance; oxidative stress; skeletal muscle
21.  Indices of Obesity and Cardiometabolic Risk 
Hypertension  2011;58(6):991-993.
doi:10.1161/HYPERTENSIONAHA.111.180406
PMCID: PMC3225025  PMID: 22025378
22.  Aldosterone and Risk for Insulin Resistance 
Hypertension  2011;58(6):998-1000.
doi:10.1161/HYPERTENSIONAHA.111.182782
PMCID: PMC3230820  PMID: 22215931
23.  Weight-loss-associated changes in bone mineral density and bone turnover after partial weight regain with or without aerobic exercise in obese women 
Background/Objectives
Moderate, long-term weight loss results in loss of bone mass in overweight or obese premenopausal women. However, whether these changes persist during weight maintenance or regain remains to be determined.
Subjects/Methods
Overweight or obese (BMI: 25.8–42.5 kg/m2) women (n=40) with at least two risk factors for the metabolic syndrome participated in this 12-mo study that examined the effects of prescribed weight loss and regain, with or without exercise, on bone turnover and on bone mineral density (BMD) in a subset of participants (n=24). During the first 6 mo, participants lost ~10% of their initial body weight via energy restriction and supervised aerobic exercise. Following weight loss, participants were randomly assigned to either an exercise or a no-exercise treatment for the regain (+50% of weight lost) phase. A one-way (time) repeated measures ANOVA tested the effects of weight loss on BMD and bone turnover, and a two-way RM ANOVA (time, exercise) was used to examine the effects of exercise during weight regain.
Results
Hip (p=0.007) and lumbar spine (p=0.05) BMD decreased with weight loss, and remained reduced after weight regain with or without exercise. Likewise, the weight-loss-associated increases in osteocalcin (p<0.001) and C-terminal peptide of type I collagen (p<0.001) persisted following weight regain, independent of exercise.
Conclusions
the results of the present study, which is the first to examine changes in bone mass and turnover during carefully controlled weight regain, suggest that weight-loss-induced perturbations in bone mass and turnover persist after partial weight regain, regardless of whether regular, weight-bearing aerobic exercise was continued.
doi:10.1038/ejcn.2011.212
PMCID: PMC3311713  PMID: 22190134
weight loss; weight regain; bone mineral density; bone turnover
24.  Dysglycemia but not lipids is associated with abnormal urinary albumin excretion in diabetic kidney disease: a report from the Kidney Early Evaluation Program (KEEP) 
BMC Nephrology  2012;13:104.
Background
The relationship between glycemic control and lipid abnormalities with urinary albumin-creatinine ratio (ACR) in chronic kidney disease (CKD) patients with diabetes mellitus (DM) is unknown. We sought to investigate the association of dyslipidemia and glycemic control with levels of albuminuria in the National Kidney Foundation (NKF) Kidney Early Evaluation Program (KEEP) participants with DM and CKD stage 3 or higher.
Methods
We performed a cross-sectional study of 6639 eligible KEEP patients with DM and CKD Stage 3 to 5 from June 2008 to December 2009. Multivariate logistic regression was used to evaluate the association of lipid parameters (per 10 mg/dl change in serum level) and glycosylated hemoglobin (HbA1c) values with three degrees of albuminuria normo (<30 mg⁄g), micro (30 to 300 mg⁄g) and macro (>300 mg⁄g).
Results
2141 KEEP participants were included. HbA1c levels were strongly associated with micro-albuminuria (compared to normo-albuminuria) and macro-albuminuria (compared to normo-albuminuria and micro-albuminuria). Each 1.0% increase in HbA1c increased the odds of micro-albuminuria by 32% (OR 1.32, 95% CI 1.23-1.42) and the odds of macro-albuminuria (vs. microalbuminuria) by 16% (OR 1.16, 95% CI 1.05-1.28). Only increases in serum HDL were associated with decreased odds of micro-albuminuria; otherwise, the association between other components of the serum lipid profile with urinary ACR did not reach statistical significance.
Conclusion
In this cross-sectional study of 2141 KEEP participants with DM and CKD stages 3–5, overall glycemic control but not lipids were associated with abnormal urinary albumin excretion, a marker of increased risk for progressive disease.
doi:10.1186/1471-2369-13-104
PMCID: PMC3480932  PMID: 22958709
Chronic Kidney Disease; Diabetes Mellitus; Proteinuria; Dyslipidemia; Glycosylated hemoglobin
25.  The Role of Team-Based Care Involving Pharmacists to Improve Cardiovascular and Renal Outcomes 
Cardiorenal Medicine  2012;2(4):243-250.
The number of patients with cardiovascular and kidney disease in the United States continues to grow as the population ages, increasing the demand on the health care system and its providers. Many patients develop chronic conditions in which optimization of care is labor intensive, specifically hypertension, hyperlipidemia, diabetes, heart failure, and chronic kidney disease. Therefore, innovative and collaborative approaches to health care are warranted. Several team-based health care models have evolved and are gaining popularity, including the Patient-Centered Medical Home (PCMH) and Medication Therapy Management (MTM). Team-based care is widely supported in the literature, demonstrating significant improvement in cardiovascular and renal outcomes. This article will review the premises of PCMH and MTM, review the evidence and roles for team-based care specific to cardiovascular and renal outcomes, and introduce fundamentals to implement collaborative practice focusing on pharmacist-provider teams.
doi:10.1159/000341725
PMCID: PMC3551433  PMID: 23381091
Collaboration; Team-based care; Cardiovascular outcomes; Renal outcomes; Pharmacist; Patient-Centered Medical Home; Medication Therapy Management

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