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Xing L, Xiong J, Hu Q, Li W, Chen L. Comparative analysis of four nutritional scores in predicting adverse outcomes in biopsy-confirmed diabetic kidney Disease. Front Nutr 2024; 11:1352030. [PMID: 38571747 PMCID: PMC10987755 DOI: 10.3389/fnut.2024.1352030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 03/04/2024] [Indexed: 04/05/2024] Open
Abstract
Malnutrition is associated with adverse outcomes in patients with diabetic kidney disease (DKD). However, it is uncertain which nutritional assessment tools are most effective in predicting the adverse outcomes of DKD. This retrospective study was conducted at a single center and included 367 patients diagnosed with DKD based on biopsy results between August 2009 and December 2018. Four nutritional assessment indices, namely the Prognostic Nutritional Index (PNI), Geriatric Nutritional Risk Index (GNRI), Triglycerides (TG) × Total Cholesterol (TC) × Body Weight (BW) Index (TCBI), and Controlling Nutritional Status (CONUT) score, were selected and calculated. We aimed to assess the association between these nutritional scores and adverse outcomes, including progression to end-stage kidney disease (ESKD), cardiovascular diseases events (CVD), and all-cause mortality. Univariate and multivariate Cox regression analyses, Kaplan-Meier analysis, along with Restricted cubic spline analysis were used to examine the relationship between nutritional scores and adverse outcomes. Furthermore, the area under the curve (AUC) was calculated using time-dependent receiver operating characteristics to determine the predictive value of the four nutritional scores alone and some combinations. Lastly, ordered logistic regression analysis was conducted to explore the correlation between the four nutritional scores and different renal histologic changes. The incidence of ESKD, CVD, and all-cause mortality was significantly higher in patients with DKD who had a lower PNI, lower GNRI, and higher CONUT score. Additionally, The TCBI performed the worst in terms of grading and risk assessment. The PNI offer the highest predictive value for adverse outcomes and a stronger correlation with renal histologic changes compared to other nutritional scores. Patients diagnosed with DKD who have a worse nutritional status are more likely to experience higher rates of adverse outcomes. The PNI might offer more valuable predictive values and a stronger correlation with different renal histologic changes compared to other nutritional scores.
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Affiliation(s)
- Lingzhi Xing
- Faculty of Pediatrics, Chongqing Medical University, Chongqing, China
- The Center of Experimental Teaching Management, Chongqing Medical University, Chongqing, China
| | - Jiachuan Xiong
- Department of Nephrology, The Key Laboratory for the Prevention and Treatment of Chronic Kidney Disease of Chongqing, Chongqing Clinical Research Center of Kidney and Urology Diseases, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Qiyuan Hu
- The Center of Experimental Teaching Management, Chongqing Medical University, Chongqing, China
| | - Wenqing Li
- Faculty of Pediatrics, Chongqing Medical University, Chongqing, China
- The Center of Experimental Teaching Management, Chongqing Medical University, Chongqing, China
| | - Ling Chen
- The Center of Experimental Teaching Management, Chongqing Medical University, Chongqing, China
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Pereira-Acácio A, Veloso-Santos JPM, Nossar LF, Costa-Sarmento G, Muzi-Filho H, Vieyra A. Angiotensin-(3–4) normalizes the elevated arterial blood pressure and abnormal Na+/energy handling associated with chronic undernutrition by counteracting the effects mediated by type 1 angiotensin II receptors. PLoS One 2022; 17:e0273385. [PMID: 35984814 PMCID: PMC9390919 DOI: 10.1371/journal.pone.0273385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 08/07/2022] [Indexed: 11/24/2022] Open
Abstract
We investigated the mechanisms by which chronic administration of a multideficient diet after weaning alters bodily Na+ handling, and culminates in high systolic blood pressure (SBP) at a juvenile age. From 28 to 92 days of age, weaned male Wistar rats were given a diet with low content and poor-quality protein, and low lipid, without vitamin supplementation, which mimics the diets consumed in impoverished regions worldwide. We measured food, energy and Na+ ingestion, together with urinary Na+ excretion, Na+ density (Na+ intake/energy intake), plasma Na+ concentration, SBP, and renal proximal tubule Na+-transporting ATPases. Undernourished rats aged 92 days had only one-third of the control body mass, lower plasma albumin, higher SBP, higher energy intake, and higher positive Na+ balance accompanied by decreased plasma Na+ concentration. Losartan or Ang-(3–4) normalized SBP, and the combination of the 2 substances induced an accentuated negative Na+ balance as a result of strong inhibition of Na+ ingestion. Na+ density in undernourished rats was higher than in control, irrespective of the treatment, and they had downregulated (Na++K+)ATPase and upregulated Na+-ATPase in proximal tubule cells, which returned to control levels after Losartan or Ang-(3–4). We conclude that Na+ density, not only Na+ ingestion, plays a central role in the pathophysiology of elevated SBP in chronically undernourished rats. The observations that Losartan and Ang-(3–4) normalized SBP together with negative Na+ balance give support to the proposal that Ang II⇒AT1R and Ang II⇒AT2R axes have opposite roles within the renin-angiotensin-aldosterone system of undernourished juvenile rats.
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Affiliation(s)
- Amaury Pereira-Acácio
- Graduate Program of Translational Biomedicine/BIOTRANS, University of Grande Rio, Duque de Caxias, Brazil
- Leopoldo de Meis Institute of Medical Biochemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Center of Structural Biology and Bioimaging/CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - João P. M. Veloso-Santos
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Center of Structural Biology and Bioimaging/CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luiz F. Nossar
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gloria Costa-Sarmento
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Center of Structural Biology and Bioimaging/CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Humberto Muzi-Filho
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Center of Structural Biology and Bioimaging/CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Adalberto Vieyra
- Graduate Program of Translational Biomedicine/BIOTRANS, University of Grande Rio, Duque de Caxias, Brazil
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Center of Structural Biology and Bioimaging/CENABIO, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Regenerative Medicine/REGENERA, Rio de Janeiro, Brazil
- * E-mail:
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3
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Zhu HG, Jiang ZS, Gong PY, Zhang DM, Zou ZW, Qian-Zhang, Ma HM, Guo ZG, Zhao JY, Dong JJ, Lin-Liao. Efficacy of low-protein diet for diabetic nephropathy: a systematic review of randomized controlled trials. Lipids Health Dis 2018; 17:141. [PMID: 29914534 PMCID: PMC6006775 DOI: 10.1186/s12944-018-0791-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 05/28/2018] [Indexed: 11/29/2022] Open
Abstract
Background A low-protein diet (LPD) is believed to be beneficial in slowing the progression of kidney disease. It is reported that low protein diet can improve protein, sugar and lipid metabolism, and reduce the symptoms and complications of renal insufficiency. However, there has been controversial regarding the effects of protein restriction on diabetic nephropathy (DN). Objective To investigate the efficacy of LPD on renal function in patients with type 1 or 2 DN by meta-analysis of randomized controlled trials (RCTs). Design PubMed, MEDLINE, EMBASE and China National Knowledge Infrastructure databases were searched. Eleven randomized controlled trials met the inclusion criteria, of which 10 were English and 1 was Chinese. The primary outcome was a change in glomerular filtration rate (GFR). The secondary outcome was a change in proteinuria. Random-effects models were used to calculate the standardized mean difference (SMD) and the corresponding 95% confidence intervals (CI). Subgroup analyses were also performed. Results Our research indicated that LPD was not associated with a significant improvement in GFR (1.59 ml · min−1 · 1.73 m−2, 95% CI -0.57, 3.75, I2 = 76%; p = 0.15). This effect was consistent across the subgroups regardless of type of diabetes, course of diabetes and intervention period. Our results also showed that there was no significant difference on improvement of proteinuria in patients of LPD and those in normal-protein diet groups (− 0.48, 95%CI-1.70, 0.74, I2 = 94%, p = 0.44). Subgroup analysis revealed that LPD resulted in increased excretion of proteinuria in patients with type 2 diabetes (1.32, 95% CI 0.17, 2.47, I2 = 86%, p = 0.02). Conclusion The present research showed that LPD was not significantly associated with improvement of renal function in patients with either type 1 or 2 diabetic nephropathy. Although these results do not completely eliminate the possibility that LPD is beneficial for patients with diabetic nephropathy, it does not seem to be significant benefit to renal function.
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Affiliation(s)
- Huan-Gao Zhu
- Division of Endocrinology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Zhao-Shun Jiang
- Division of Endocrinology, The General Hospital of Jinan Military Command, 25 Shifan Road, Jinan, 250031, Shandong, China
| | - Pi-Yun Gong
- Division of Endocrinology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Dong-Mei Zhang
- Division of Endocrinology, The Ninth Hospital of Xi An, Shan xi, China
| | - Zhi-Wei Zou
- Division of Endocrinology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Qian-Zhang
- Division of Endocrinology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Hui-Mei Ma
- Division of Endocrinology, Qilu Hospital of Shandong University, Jinan, Shandong, China
| | - Zhen-Gang Guo
- Internal medicine department, Guanxian hospital of traditional Chinese medicine, Liaocheng, Shandong, China
| | - Jun-Yu Zhao
- Division of Endocrinology, Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China
| | - Jian-Jun Dong
- Division of Endocrinology, Qilu Hospital of Shandong University, Jinan, Shandong, China.
| | - Lin-Liao
- Division of Endocrinology, Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China.
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Silva FC, de Menezes RC, Chianca DA. The implication of protein malnutrition on cardiovascular control systems in rats. Front Physiol 2015; 6:246. [PMID: 26388783 PMCID: PMC4557349 DOI: 10.3389/fphys.2015.00246] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 08/17/2015] [Indexed: 01/01/2023] Open
Abstract
The malnutrition in early life is associated with metabolic changes and cardiovascular impairment in adulthood. Deficient protein intake-mediated hypertension has been observed in clinical and experimental studies. In rats, protein malnutrition also increases the blood pressure and enhances heart rate and sympathetic activity. In this review, we discuss the effects of post-weaning protein malnutrition on the resting mean arterial pressure and heart rate and their variabilities, cardiovascular reflexes sensitivity, cardiac autonomic balance, sympathetic and renin-angiotensin activities and neural plasticity during adult life. These insights reveal an interesting prospect on the autonomic modulation underlying the cardiovascular imbalance and provide relevant information on preventing cardiovascular diseases.
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Affiliation(s)
- Fernanda C Silva
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Biological Sciences, Federal University of Ouro Preto Ouro Preto, Brazil ; Graduate Program in Biological Sciences - CBIOL/NUPEB, Federal University of Ouro Preto Ouro Preto, Brazil
| | - Rodrigo C de Menezes
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Biological Sciences, Federal University of Ouro Preto Ouro Preto, Brazil ; Graduate Program in Biological Sciences - CBIOL/NUPEB, Federal University of Ouro Preto Ouro Preto, Brazil
| | - Deoclécio A Chianca
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Institute of Biological Sciences, Federal University of Ouro Preto Ouro Preto, Brazil ; Graduate Program in Biological Sciences - CBIOL/NUPEB, Federal University of Ouro Preto Ouro Preto, Brazil
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5
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Altered signaling pathways linked to angiotensin II underpin the upregulation of renal Na(+)-ATPase in chronically undernourished rats. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2357-66. [PMID: 25283821 DOI: 10.1016/j.bbadis.2014.09.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 09/17/2014] [Accepted: 09/30/2014] [Indexed: 01/23/2023]
Abstract
This study has investigated the participation of altered signaling linked to angiotensin II (Ang II) that could be associated with increased Na(+) reabsorption in renal proximal tubules during chronic undernutrition. A multideficient chow for rats (basic regional diet, BRD) was used, which mimics several human diets widely taken in developing countries. The Vmax of the ouabain-resistant Na(+)-ATPase resident in the basolateral membranes increased >3-fold (P<0.001) accompanied by an increase in Na(+) affinity from 4.0 to 0.2mM (P<0.001). BRD rats had a >3-fold acceleration of the formation of phosphorylated intermediates in the early stage of the catalytic cycle (in the E1 conformation) (P<0.001). Immunostaining showed a huge increase in Ang II-positive cells in the cortical tubulointerstitium neighboring the basolateral membranes (>6-fold, P<0.001). PKC isoforms (α, ε, λ, ζ), Ang II type 1 receptors and PP2A were upregulated in BRD rats (in %): 55 (P<0.001); 35 (P<0.01); 125, 55, 11 and 30 (P<0.001). PKA was downregulated by 55% (P<0.001). With NetPhosK 1.0 and NetPhos 2.0, we detected 4 high-score (>0.70) regulatory phosphorylation sites for PKC and 1 for PKA in the primary sequence of the Na(+)-ATPase α-subunit, which are located in domains that are key for Na(+) binding and catalysis. Therefore, chronic undernutrition stimulates tubulointerstitial activity of Ang II and impairs PKC- and PKA-mediated regulatory phosphorylation, which culminates in an exaggerated Na(+) reabsorption across the proximal tubular epithelium.
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6
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Modulation of aquaporin 2 expression in the kidney of young goats by changes in nitrogen intake. J Comp Physiol B 2014; 184:929-36. [DOI: 10.1007/s00360-014-0849-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 07/16/2014] [Accepted: 07/19/2014] [Indexed: 12/28/2022]
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7
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Silva PA, Monnerat-Cahli G, Pereira-Acácio A, Luzardo R, Sampaio LS, Luna-Leite MA, Lara LS, Einicker-Lamas M, Panizzutti R, Madeira C, Vieira-Filho LD, Castro-Chaves C, Ribeiro VS, Paixão ADO, Medei E, Vieyra A. Mechanisms involving Ang II and MAPK/ERK1/2 signaling pathways underlie cardiac and renal alterations during chronic undernutrition. PLoS One 2014; 9:e100410. [PMID: 24983243 PMCID: PMC4077653 DOI: 10.1371/journal.pone.0100410] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 05/27/2014] [Indexed: 02/07/2023] Open
Abstract
Background Several studies have correlated protein restriction associated with other nutritional deficiencies with the development of cardiovascular and renal diseases. The driving hypothesis for this study was that Ang II signaling pathways in the heart and kidney are affected by chronic protein, mineral and vitamin restriction. Methodology/Principal Findings Wistar rats aged 90 days were fed from weaning with either a control or a deficient diet that mimics those used in impoverished regions worldwide. Such restriction simultaneously increased ouabain-insensitive Na+-ATPase and decreased (Na++K+)ATPase activity in the same proportion in cardiomyocytes and proximal tubule cells. Type 1 angiotensin II receptor (AT1R) was downregulated by that restriction in both organs, whereas AT2R decreased only in the kidney. The PKC/PKA ratio increased in both tissues and returned to normal values in rats receiving Losartan daily from weaning. Inhibition of the MAPK pathway restored Na+-ATPase activity in both organs. The undernourished rats presented expanded plasma volume, increased heart rate, cardiac hypertrophy, and elevated systolic pressure, which also returned to control levels with Losartan. Such restriction led to electrical cardiac remodeling represented by prolonged ventricular repolarization parameters, induced triggered activity, early after-depolarization and delayed after-depolarization, which were also prevented by Losartan. Conclusion/Significance The mechanisms responsible for these alterations are underpinned by an imbalance in the PKC- and PKA-mediated pathways, with participation of angiotensin receptors and by activation of the MAPK/ERK1/2 pathway. These cellular and molecular alterations culminate in cardiac electric remodeling and in the onset of hypertension in adulthood.
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Affiliation(s)
- Paulo A. Silva
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
| | - Gustavo Monnerat-Cahli
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
| | - Amaury Pereira-Acácio
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
| | - Ricardo Luzardo
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
| | - Luzia S. Sampaio
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
| | - Marcia A. Luna-Leite
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lucienne S. Lara
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcelo Einicker-Lamas
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
| | - Rogério Panizzutti
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Caroline Madeira
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leucio D. Vieira-Filho
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, Brazil
| | - Carmen Castro-Chaves
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, Brazil
| | - Valdilene S. Ribeiro
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, Brazil
| | - Ana D. O. Paixão
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, Brazil
| | - Emiliano Medei
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
| | - Adalberto Vieyra
- Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil
- * E-mail:
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8
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Abstract
Diabetic nephropathy is the leading cause of progressive kidney disease, leading to end-stage renal disease and renal replacement therapy. Angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers have been considered effective at slowing the progression of kidney function deterioration. However, these drugs cannot sufficiently halt the progression of nephropathy to the extent that is required. A low-protein diet (LPD) is believed to be a nutritional intervention that may slow kidney disease progression. In fact, preclinical animal experiments have demonstrated excellent renoprotective effects of an LPD. However, in human clinical trials, analyses of the effects of protein restriction on diabetic nephropathy have not yet revealed consistently positive outcomes of this nutritional intervention. In this review, we analyze the potential renoprotective effects of an LPD on diabetic nephropathy and summarize the outcomes of clinical trials that have systematically investigated the efficacy of an LPD in diabetic nephropathy. In addition, we discuss some potential approaches associated with nutritional interventions to combat progressive kidney disease.
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Affiliation(s)
- Toshiki Otoda
- Department of Diabetology & Endocrinology, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Kahoku, Ishikawa, 920-0293, Japan
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9
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Gomide JMC, de Menezes RC, Fernandes LG, Silva FC, Cardoso LM, Miranda PH, da Silva Jr LG, Lima MP, Pesquero JL, Foureaux G, Ferreira AJ, Chianca-Jr DA. Increased activity of the renin-angiotensin and sympathetic nervous systems is required for regulation of the blood pressure in rats fed a low-protein diet. Exp Physiol 2012; 98:57-66. [DOI: 10.1113/expphysiol.2012.066712] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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10
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Murça TM, Magno TSDR, De Maria MLDA, Capuruço CAB, Chianca DA, Ferreira AJ. Cardiac responses of rats submitted to postnatal protein restriction. Appl Physiol Nutr Metab 2012; 37:455-62. [PMID: 22497279 DOI: 10.1139/h2012-017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Undernutrition during critical stages of development and childhood has important effects on cardiovascular homeostasis. The present study was undertaken to evaluate the in vivo and ex vivo cardiac function of rats submitted to postnatal protein restriction. Male Wistar rats (28 days old) were fed a regular (20%) or low-protein (6%) diet over 5 weeks. After this period, cardiac function was analyzed by echocardiography and isolated heart preparation. Furthermore, the density of cardiac noradrenergic fibers and hematological profile were evaluated. We found that malnourished rats exhibited elevated arterial blood pressure, increased fractional shortening (echocardiography), increased systolic tension, increased ±dT/dt (isolated heart technique), impaired diastolic function characterized by a slight increase in the left ventricular end-diastolic diameter (echocardiography) and decreased diastolic tension (isolated heart technique), and cardiac hypertrophy evidenced by augmentation of the posterior left ventricular wall and discrete hematological changes. In addition, malnourished rats exhibited increased noradrenergic fiber density in their hearts (0.08% ± 0.02% area in control rats vs. 0.17% ± 0.03% area in malnourished rats). Our current data demonstrate that postnatal protein restriction causes cardiac adaptation characterized by an early overworking heart. This is at least in part mediated by an increase in the efferent sympathetic fibers to the heart. These findings provide important information for efforts to prevent and manage the consequences of undernutrition in the human population.
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11
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Loss IDO, Fernandes LG, Martins CDD, Cardoso LM, Silva ME, Dias-da-Silva VJ, Moraes MFD, Chianca DA. Baroreflex dysfunction in rats submitted to protein restriction. Life Sci 2007; 81:944-50. [PMID: 17822720 DOI: 10.1016/j.lfs.2007.08.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Revised: 07/16/2007] [Accepted: 08/03/2007] [Indexed: 11/23/2022]
Abstract
Earlier studies from the authors' laboratory showed that malnourishment induces alterations in the cardiovascular homeostasis increasing the basal mean arterial pressure and heart rate. In this study, the authors evaluated whether the sympathetic and parasympathetic efferent activities contribute to changes in the cardiovascular homeostasis through altered modulation of the arterial baroreflex of malnourished rats. After weaning, male Fischer rats were given 15% (Normal Protein--NP) or 6% (Low Protein--LP) protein diet for 35 d. The baroreflex gain and latency were evaluated before and after selective autonomic blockades in control and malnourished rats. It was observed that malnourishment affected the baroreflex gain in response to activation and deactivation of the arterial baroreflex. Moreover, malnourished rats showed increased baroreflex latency as compared to that of control rats. Regarding the autonomic efferent activity directed to the heart, the data showed increased sympathetic and decreased parasympathetic efferent activities in malnourished rats, and such alterations could be related to the observed changes in the arterial baroreflex gain as well as in the basal mean arterial pressure and heart rate.
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Affiliation(s)
- Igor de O Loss
- Department of Biological Sciences, DECBI-NUPEB, Federal University of Ouro Preto, 35400-000, Ouro Preto, MG, Brazil
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12
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Penitente AR, Fernandes LG, Cardoso LM, Silva ME, Pedrosa ML, Silva AL, Haibara AS, Moraes MFD, Chianca DAJ. Malnutrition enhances cardiovascular responses to chemoreflex activation in awake rats. Life Sci 2007; 81:609-14. [PMID: 17688888 DOI: 10.1016/j.lfs.2007.07.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 06/29/2007] [Accepted: 07/06/2007] [Indexed: 11/24/2022]
Abstract
Several studies in the literature suggest that low-protein intake is associated with increases in sympathetic efferent activity and cardiovascular disease. Among the possible mechanisms, changes in the neurotransmission of cardiovascular reflexes have been implicated. Therefore, the present study comprised the evaluation of chemoreflex responsiveness in rats subjected to a low-protein diet during the 35 days after weaning. As a result, we observed that malnourished rats presented higher levels of baseline mean arterial pressure and heart rate and exhibited a mild increase in the pressor response to chemoreflex activation. They also exhibited a massive bradycardic response to chemoreflex activation. Interestingly, bilateral ligature of the carotid body arteries further increased baseline mean arterial pressure and heart rate in malnourished animals. The data suggest severe autonomic imbalance and/or change in the central interplay between neural and cardiovascular mechanisms.
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Affiliation(s)
- Arlete Rita Penitente
- Department of Biological Sciences, ICEB/NUPEB, Federal University of Ouro Preto, 35400-000, Ouro Preto, MG, Brazil
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13
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Tropia FC, Cardoso LM, Pedrosa ML, Silva ME, Haibara AS, Moraes MF, Chianca DA. Effects of low-protein diet on the baroreflex and Bezold-Jarisch reflex in conscious rats. Nutr Neurosci 2002; 4:99-107. [PMID: 11842885 DOI: 10.1080/1028415x.2001.11747354] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The present study evaluated the effects of a low-protein diet (LP, 6% protein) on cardiovascular reflexes of Male Fisher rats. Three experimental groups, and their respective controls (15% protein), were used: (1) Baroreceptor reflex (BAR); (2) Bezold-Jarisch reflex (BJR); and (3) Prazosin treated. Dietary restriction began after weaning (three weeks) and lasted for a period of five weeks, after which animals were subjected to the experimental protocols. The BAR group was evaluated through injections of phenylephrine (0.5-5.0 microgram/Kg, i.v.) and sodium nitroprusside (0.7-7.0 microgram/Kg, i.v.) while the BJR was evaluated through injections of serotonin (2.5-10 microgram/Kg, i.v.). Our results showed an increased baroreflex gain bradycardia for the LP group (-0.96+/-0.34 vs. -2.12+/-1.06 bpm/mmHg) and a larger bradycardia for the BJR the LP group (160+/-18% greater than controls). Basal cardiovascular parameters were not different between LP and control rats, however LP animals treated with prazosin resulted in a larger fall of blood pressure (-19+/-3 vs. -28+/-5 mmHg). In conclusion, LP rats present an increased responsiveness of BAR and BJR, which could contribute to their normal levels of cardiovascular parameters, in spite of the possible increase in the sympathetic vasomotor tonus observed with the prazosin protocol.
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Affiliation(s)
- F C Tropia
- Department of Biological Sciences, DECBI, Federal University of Ouro Preto, MG, Brazil
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