Claudia Tovar-Palacio - Academia.edu (original) (raw)
Papers by Claudia Tovar-Palacio
Current developments in nutrition, Jul 1, 2024
International Journal of Molecular Sciences, Apr 28, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
New Journal of Chemistry, 2019
Cyclodipeptides cyclo(l-Pro-l-Leu),1; cyclo(l-Pro-l-Val),2; and cyclo (l-Pro-l-Phe),3fromPseudomo... more Cyclodipeptides cyclo(l-Pro-l-Leu),1; cyclo(l-Pro-l-Val),2; and cyclo (l-Pro-l-Phe),3fromPseudomonas fluorescensIB-MR-66e showed α-glucosidase inhibitory activity.
Nutrients, Feb 3, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
American Journal of Physiology-endocrinology and Metabolism, 2018
Inactivation of SPAK kinase reduces body weight gain in mice fed a high-fat diet by improving ene... more Inactivation of SPAK kinase reduces body weight gain in mice fed a high-fat diet by improving energy expenditure and insulin sensitivity.
Genes and Nutrition, Apr 25, 2012
Nuclear receptors are ligand-activated transcriptional regulators of several key aspects of renal... more Nuclear receptors are ligand-activated transcriptional regulators of several key aspects of renal physiology and pathophysiology. As such, nuclear receptors control a large variety of metabolic processes, including kidney lipid metabolism, drug clearance, inflammation, fibrosis, cell differentiation, and oxidative stress. Derangement of nuclear receptor regulation, that is, mainly due to obesity may induce metabolic syndrome, may contribute to the pathogenesis and progression of chronic renal disease and may result in end-stage renal disease. This places nuclear receptors at the forefront of novel therapeutic approaches for a broad range of kidney disorders and diseases, including glomerulosclerosis, tubulointerstitial disease, renal lipotoxicity, kidney fibrosis, and hypertension. This review focuses on the importance of the transcription factors peroxisome proliferator-activated receptor alpha, peroxisome proliferator-activated receptor beta, peroxisome proliferator-activated receptor gamma, liver X receptors, farnesoid X receptor, and the pregnane X receptor/steroid and xenobiotic receptor (PXR) on the physiology and pathophysiology of renal diseases associated with obesity and metabolic syndrome. Keywords Kidney Á Nuclear receptors Á Obesity Á Metabolic syndrome The role of nuclear receptors in kidney disease Due to the consumption of a Western-style diet and a sedentary lifestyle, obesity is rapidly becoming the most important health problem challenging developed and nondeveloped countries. Although obesity is often associated with diabetes and hypertension, which are the two most common risk factors for the development of end-stage renal disease, obesity has been suggested as an independent risk factor for the development of chronic kidney disease (Praga and Morales 2006; Rutkowski et al. 2006; Wahba and Mak 2007; Wang et al. 2008). Early in the course of obesity, structural and functional changes similar to diabetic kidney disease occur (Henegar et al. 2001). These changes, considered to be precursors to more severe renal injury, include glomerular hyperfiltration, glomerular basement membrane thickening, mesangial cell proliferation, mesangial matrix thickening, and expansion of the Bowman's capsule. Morbid obesity has been associated with the eventual development of focal and segmental glomerulosclerosis even in the absence of diabetes (Kambham et al. 2001; Praga 2002). Studies in humans and in animal models have reported that accumulation of lipids in the kidney has been shown to promote renal disease (Kimmelstiel and Wilson 1936; Wilens and Elster 1950; Proctor et al. 2006; Jiang et al. 2005; Tovar-Palacio et al. 2011). Heavy glomerular proteinuria (nephritic syndrome) is associated with hyperlipidemia, lipiduria, and progressive kidney disease. Glomerular and tubular epithelial cells in the nephritic kidney are exposed to large quantities of lipids bound to filtered proteins, the uptake of which raises cellular lipids.
International Journal of Molecular Sciences
Obesity causes systemic inflammation, hepatic and renal damage, as well as gut microbiota dysbios... more Obesity causes systemic inflammation, hepatic and renal damage, as well as gut microbiota dysbiosis. Alternative vegetable sources rich in polyphenols are known to prevent or delay the progression of metabolic abnormalities during obesity. Vachellia farnesiana (VF) is a potent source of polyphenols with antioxidant and anti-inflammatory activities with potential anti-obesity effects. We performed an in vivo preventive or an interventional experimental study in mice and in vitro experiments with different cell types. In the preventive study, male C57BL/6 mice were fed with a Control diet, a high-fat diet, or a high-fat diet containing either 0.1% methyl gallate, 10% powdered VFP, or 0.5%, 1%, or 2% of a polyphenolic extract (PE) derived from VFP (Vachellia farnesiana pods) for 14 weeks. In the intervention study, two groups of mice were fed for 14 weeks with a high-fat diet and then one switched to a high-fat diet with 10% powdered VFP for ten additional weeks. In the in vitro studie...
The roots of the cactus Peniocereus greggii, which grows in Northern Mexico and in the south of A... more The roots of the cactus Peniocereus greggii, which grows in Northern Mexico and in the south of Arizona, are highly valued by the Pima to treat diabetes and other illnesses, such as breast pain and common cold. As part of our chemical and pharmacological investigation on medicinal plants used for treating diabetes, herein we report the hypoglycemic and antihyperglycemic action of a decoction prepared from the roots of the plant. The active compounds were a series of cholestane steroids, namely, peniocerol (2), desoxyviperidone (3), viperidone (4), and viperidinone (5). Also, a new chemical entity was obtained from an alkalinized chloroform extract (CE1), which was characterized as 3,6-dihydroxycholesta-5,8(9),14-trien-7-one (6) by spectroscopic means. Desoxyviperidone (3) showed an antihyperglycemic action during an oral glucose tolerance test. Compound 3 was also able to decrease blood glucose levels during an intraperitoneal insulin tolerance test in hyperglycemic mice only in combination with insulin, thus behaving as an insulin sensitizer agent. Nevertheless, mitochondrial bioenergetic experiments revealed that compounds 3 and 6 increased basal respiration and proton leak, without affecting the respiration associated with ATP production in C2C12 myotubes. Finally, an ultraefficiency liquid chromatographic method for quantifying desoxyviperidone (3) and viperidone (4) in the crude drug was developed and validated. Altogether, our results demonstrate that Peniocereus greggii decoction possesses a hypoglycemic and antihyperglycemic action in vivo, that sterols 2 and 6 promotes insulin secretion in vitro, and that desoxyviperidone (3) physiologically behaves as an insulin sensitizer agent by a mechanism that may involve mitochondrial proton leak.
Biomolecules
Renal injury observed in several pathologies has been associated with lipid accumulation in the k... more Renal injury observed in several pathologies has been associated with lipid accumulation in the kidney. While it has been suggested that the accumulation of renal lipids depends on free fatty acids released from adipose tissue, it is not known whether in situ renal lipogenesis due to endoplasmic reticulum (ER) stress contributes to kidney injury. The aim of the present study was to elucidate the role of pharmacological ER stress in renal structure and function and its effect on renal lipid metabolism of C57BL/6 mice. ER stress increased serum creatinine and induced kidney structural abnormalities. Tunicamycin-administered mice developed hyperinsulinemia, augmented lipolysis and increased circulating leptin and adiponectin. Renal unfolded protein response (UPR) gene expression markers, the lipogenic transcription factor SREBP1 and the phosphorylation of eIF2α increased 8 h after tunicamycin administration. At 24 h, an increase in BiP protein content was accompanied by a reduction in ...
Food Chemistry, Function and Analysis
Nutrition, Metabolism and Cardiovascular Diseases
BACKGROUND AND AIM Circulating amino acids are modified by sex, body mass index (BMI) and insulin... more BACKGROUND AND AIM Circulating amino acids are modified by sex, body mass index (BMI) and insulin resistance (IR). However, whether the presence of genetic variants in branched-chain amino acid (BCAA) catabolic enzymes modifies circulating amino acids is still unknown. Thus, we determined the frequency of two genetic variants, one in the branched-chain aminotransferase 2 (BCAT2) gene (rs11548193), and one in the branched-chain ketoacid dehydrogenase (BCKDH) gene (rs45500792), and elucidated their impact on circulating amino acid levels together with clinical, anthropometric and biochemical parameters. METHODS AND RESULTS We performed a cross-sectional comparative study in which we recruited 1612 young adults (749 women and 863 men) aged 19.7 ± 2.1 years and with a BMI of 24.9 ± 4.7 kg/m2. Participants underwent clinical evaluation and provided blood samples for DNA extraction and biochemical analysis. The single nucleotide polymorphisms (SNPs) were determined by allelic discrimination using real-time polymerase chain reaction (PCR). The frequencies of the less common alleles were 15.2 % for BCAT2 and 9.83 % for BCKDH. The subjects with either the BCAT2 or BCKDH SNPs displayed no differences in the evaluated parameters compared with subjects homozygotes for the most common allele at each SNP. However, subjects with both SNPs had higher body weight, BMI, blood pressure, glucose, and circulating levels of aspartate, isoleucine, methionine, and proline than the subjects homozygotes for the most common allele (P < 0.05, One-way ANOVA). CONCLUSION Our findings suggest that the joint presence of both the BCAT2 rs11548193 and BCKDH rs45500792 SNPs induces metabolic alterations that are not observed in subjects without either SNP.
The ability of alcohol extract of isolated soy protein to contribute to the hypochoesterolemic ef... more The ability of alcohol extract of isolated soy protein to contribute to the hypochoesterolemic effect mediated by the intake of soy protein was tested in gerbils. Gerbils were assigned to five different groups (n Å 8) and provided experimental diets for 28 d. Diets contained either casein or alcohol-washed isolated soy protein (ISP). The ISP diet was provided alone, or supplemented with one of three different levels of an alcohol extract of isolated soy protein contributing either 2.1, 3.6 or 6.2 mg isoflavones/g protein. Gerbils fed all of the soy-based diets had significantly lower (P õ 0.05) total cholesterol, LDL / VLDL cholesterol, and apolipoprotein B concentrations than those fed casein. The addition of the alcohol extract to ISP did not reduce serum cholesterol concentrations any further, but reduced hepatic apolipoprotein A-I mRNA levels (Põ 0.05) compared with casein- and ISP-fed groups. Levels of apolipoprotein E mRNA were not affected by diet. These data suggest that in ...
Archives of Medical Research, 2011
Background and Aims. Dietary fat plays a central role in the development of obesity. However, the... more Background and Aims. Dietary fat plays a central role in the development of obesity. However, the metabolic consequences of dietary fat can vary depending on their fatty acid composition. Therefore, the aim of the present work was to study the effect of the type and amount of dietary fat on the expression of genes controlling lipogenesis and fatty acid oxidation in the liver or adipose tissue of rats. Methods. The expression of hepatic or adipose tissue lipid metabolic genes from Sprague Dawley or Zucker fa/fa rats, respectively, was measured after chronic consumption of diets containing different types/amounts of dietary fats or after rats were adapted for 2 months to a high-fat Western diet and then fed different types and amounts of fats. Results. Each fat or oil in the diet regulated differentially the expression of transcription factors involved in lipogenesis and fatty acid oxidation as well as some of its target genes in liver. The expression of these genes after a chronic consumption of a high-fat Western diet was reestablished in the presence of less dietary fat and was dependent on the type of fat. In obese Zucker fa/fa rats, consumption of a high-fat diet repressed the expression of lipogenic, fatty acid oxidation and thermogenic genes in adipose tissue. Conclusions. Type of fat influences the expression of genes that are involved in lipid metabolism in liver and adipose tissue, but this response is repressed when the amount of dietary fat is excessive, diminishing the differences between each type of fat.
AJP: Renal Physiology, 2004
The mammalian kidney bumetanide-sensitive Na+-K+-2Cl− and thiazide-sensitive Na+-Cl− cotransporte... more The mammalian kidney bumetanide-sensitive Na+-K+-2Cl− and thiazide-sensitive Na+-Cl− cotransporters are the major pathways for salt reabsorption in the thick ascending limb of Henle's loop and distal convoluted tubule, respectively. These cotransporters serve as receptors for the loop- and thiazide-type diuretics, and inactivating mutations of corresponding genes are associated with development of Bartter's syndrome type I and Gitleman's disease, respectively. Structural requirements for ion translocation and diuretic binding specificity are unknown. As an initial approach for analyzing structural determinants conferring ion or diuretic preferences in these cotransporters, we exploited functional differences and structural similarities between Na+-K+-2Cl− and Na+-Cl− cotransporters to design and study chimeric proteins in which the NH2-terminal and/or COOH-terminal domains were switched between each other. Thus six chimeric proteins were produced. Using the heterologous ...
AJP: Renal Physiology, 2011
Obesity is a risk factor for the development of chronic kidney disease (CKD) and end-stage renal ... more Obesity is a risk factor for the development of chronic kidney disease (CKD) and end-stage renal disease. It is not clear whether the adoption of a high-protein diet in obese patients affects renal lipid metabolism or kidney function. Thus the aims of this study were to assess in obese Zucker fa/ fa rats the effects of different types and amounts of dietary protein on the expression of lipogenic and inflammatory genes, as well as renal lipid concentration and biochemical parameters of kidney function. Rats were fed different concentrations of soy protein or casein (20, 30, 45%) for 2 mo. Independent of the type of protein ingested, higher dietary protein intake led to higher serum triglycerides (TG) than rats fed adequate concentrations of protein. Additionally, the soy protein diet significantly increased serum TG compared with the casein diet. However, rats fed soy protein had significantly decreased serum cholesterol concentrations compared with those fed a casein diet. No signif...
Current developments in nutrition, Jul 1, 2024
International Journal of Molecular Sciences, Apr 28, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
New Journal of Chemistry, 2019
Cyclodipeptides cyclo(l-Pro-l-Leu),1; cyclo(l-Pro-l-Val),2; and cyclo (l-Pro-l-Phe),3fromPseudomo... more Cyclodipeptides cyclo(l-Pro-l-Leu),1; cyclo(l-Pro-l-Val),2; and cyclo (l-Pro-l-Phe),3fromPseudomonas fluorescensIB-MR-66e showed α-glucosidase inhibitory activity.
Nutrients, Feb 3, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
American Journal of Physiology-endocrinology and Metabolism, 2018
Inactivation of SPAK kinase reduces body weight gain in mice fed a high-fat diet by improving ene... more Inactivation of SPAK kinase reduces body weight gain in mice fed a high-fat diet by improving energy expenditure and insulin sensitivity.
Genes and Nutrition, Apr 25, 2012
Nuclear receptors are ligand-activated transcriptional regulators of several key aspects of renal... more Nuclear receptors are ligand-activated transcriptional regulators of several key aspects of renal physiology and pathophysiology. As such, nuclear receptors control a large variety of metabolic processes, including kidney lipid metabolism, drug clearance, inflammation, fibrosis, cell differentiation, and oxidative stress. Derangement of nuclear receptor regulation, that is, mainly due to obesity may induce metabolic syndrome, may contribute to the pathogenesis and progression of chronic renal disease and may result in end-stage renal disease. This places nuclear receptors at the forefront of novel therapeutic approaches for a broad range of kidney disorders and diseases, including glomerulosclerosis, tubulointerstitial disease, renal lipotoxicity, kidney fibrosis, and hypertension. This review focuses on the importance of the transcription factors peroxisome proliferator-activated receptor alpha, peroxisome proliferator-activated receptor beta, peroxisome proliferator-activated receptor gamma, liver X receptors, farnesoid X receptor, and the pregnane X receptor/steroid and xenobiotic receptor (PXR) on the physiology and pathophysiology of renal diseases associated with obesity and metabolic syndrome. Keywords Kidney Á Nuclear receptors Á Obesity Á Metabolic syndrome The role of nuclear receptors in kidney disease Due to the consumption of a Western-style diet and a sedentary lifestyle, obesity is rapidly becoming the most important health problem challenging developed and nondeveloped countries. Although obesity is often associated with diabetes and hypertension, which are the two most common risk factors for the development of end-stage renal disease, obesity has been suggested as an independent risk factor for the development of chronic kidney disease (Praga and Morales 2006; Rutkowski et al. 2006; Wahba and Mak 2007; Wang et al. 2008). Early in the course of obesity, structural and functional changes similar to diabetic kidney disease occur (Henegar et al. 2001). These changes, considered to be precursors to more severe renal injury, include glomerular hyperfiltration, glomerular basement membrane thickening, mesangial cell proliferation, mesangial matrix thickening, and expansion of the Bowman's capsule. Morbid obesity has been associated with the eventual development of focal and segmental glomerulosclerosis even in the absence of diabetes (Kambham et al. 2001; Praga 2002). Studies in humans and in animal models have reported that accumulation of lipids in the kidney has been shown to promote renal disease (Kimmelstiel and Wilson 1936; Wilens and Elster 1950; Proctor et al. 2006; Jiang et al. 2005; Tovar-Palacio et al. 2011). Heavy glomerular proteinuria (nephritic syndrome) is associated with hyperlipidemia, lipiduria, and progressive kidney disease. Glomerular and tubular epithelial cells in the nephritic kidney are exposed to large quantities of lipids bound to filtered proteins, the uptake of which raises cellular lipids.
International Journal of Molecular Sciences
Obesity causes systemic inflammation, hepatic and renal damage, as well as gut microbiota dysbios... more Obesity causes systemic inflammation, hepatic and renal damage, as well as gut microbiota dysbiosis. Alternative vegetable sources rich in polyphenols are known to prevent or delay the progression of metabolic abnormalities during obesity. Vachellia farnesiana (VF) is a potent source of polyphenols with antioxidant and anti-inflammatory activities with potential anti-obesity effects. We performed an in vivo preventive or an interventional experimental study in mice and in vitro experiments with different cell types. In the preventive study, male C57BL/6 mice were fed with a Control diet, a high-fat diet, or a high-fat diet containing either 0.1% methyl gallate, 10% powdered VFP, or 0.5%, 1%, or 2% of a polyphenolic extract (PE) derived from VFP (Vachellia farnesiana pods) for 14 weeks. In the intervention study, two groups of mice were fed for 14 weeks with a high-fat diet and then one switched to a high-fat diet with 10% powdered VFP for ten additional weeks. In the in vitro studie...
The roots of the cactus Peniocereus greggii, which grows in Northern Mexico and in the south of A... more The roots of the cactus Peniocereus greggii, which grows in Northern Mexico and in the south of Arizona, are highly valued by the Pima to treat diabetes and other illnesses, such as breast pain and common cold. As part of our chemical and pharmacological investigation on medicinal plants used for treating diabetes, herein we report the hypoglycemic and antihyperglycemic action of a decoction prepared from the roots of the plant. The active compounds were a series of cholestane steroids, namely, peniocerol (2), desoxyviperidone (3), viperidone (4), and viperidinone (5). Also, a new chemical entity was obtained from an alkalinized chloroform extract (CE1), which was characterized as 3,6-dihydroxycholesta-5,8(9),14-trien-7-one (6) by spectroscopic means. Desoxyviperidone (3) showed an antihyperglycemic action during an oral glucose tolerance test. Compound 3 was also able to decrease blood glucose levels during an intraperitoneal insulin tolerance test in hyperglycemic mice only in combination with insulin, thus behaving as an insulin sensitizer agent. Nevertheless, mitochondrial bioenergetic experiments revealed that compounds 3 and 6 increased basal respiration and proton leak, without affecting the respiration associated with ATP production in C2C12 myotubes. Finally, an ultraefficiency liquid chromatographic method for quantifying desoxyviperidone (3) and viperidone (4) in the crude drug was developed and validated. Altogether, our results demonstrate that Peniocereus greggii decoction possesses a hypoglycemic and antihyperglycemic action in vivo, that sterols 2 and 6 promotes insulin secretion in vitro, and that desoxyviperidone (3) physiologically behaves as an insulin sensitizer agent by a mechanism that may involve mitochondrial proton leak.
Biomolecules
Renal injury observed in several pathologies has been associated with lipid accumulation in the k... more Renal injury observed in several pathologies has been associated with lipid accumulation in the kidney. While it has been suggested that the accumulation of renal lipids depends on free fatty acids released from adipose tissue, it is not known whether in situ renal lipogenesis due to endoplasmic reticulum (ER) stress contributes to kidney injury. The aim of the present study was to elucidate the role of pharmacological ER stress in renal structure and function and its effect on renal lipid metabolism of C57BL/6 mice. ER stress increased serum creatinine and induced kidney structural abnormalities. Tunicamycin-administered mice developed hyperinsulinemia, augmented lipolysis and increased circulating leptin and adiponectin. Renal unfolded protein response (UPR) gene expression markers, the lipogenic transcription factor SREBP1 and the phosphorylation of eIF2α increased 8 h after tunicamycin administration. At 24 h, an increase in BiP protein content was accompanied by a reduction in ...
Food Chemistry, Function and Analysis
Nutrition, Metabolism and Cardiovascular Diseases
BACKGROUND AND AIM Circulating amino acids are modified by sex, body mass index (BMI) and insulin... more BACKGROUND AND AIM Circulating amino acids are modified by sex, body mass index (BMI) and insulin resistance (IR). However, whether the presence of genetic variants in branched-chain amino acid (BCAA) catabolic enzymes modifies circulating amino acids is still unknown. Thus, we determined the frequency of two genetic variants, one in the branched-chain aminotransferase 2 (BCAT2) gene (rs11548193), and one in the branched-chain ketoacid dehydrogenase (BCKDH) gene (rs45500792), and elucidated their impact on circulating amino acid levels together with clinical, anthropometric and biochemical parameters. METHODS AND RESULTS We performed a cross-sectional comparative study in which we recruited 1612 young adults (749 women and 863 men) aged 19.7 ± 2.1 years and with a BMI of 24.9 ± 4.7 kg/m2. Participants underwent clinical evaluation and provided blood samples for DNA extraction and biochemical analysis. The single nucleotide polymorphisms (SNPs) were determined by allelic discrimination using real-time polymerase chain reaction (PCR). The frequencies of the less common alleles were 15.2 % for BCAT2 and 9.83 % for BCKDH. The subjects with either the BCAT2 or BCKDH SNPs displayed no differences in the evaluated parameters compared with subjects homozygotes for the most common allele at each SNP. However, subjects with both SNPs had higher body weight, BMI, blood pressure, glucose, and circulating levels of aspartate, isoleucine, methionine, and proline than the subjects homozygotes for the most common allele (P < 0.05, One-way ANOVA). CONCLUSION Our findings suggest that the joint presence of both the BCAT2 rs11548193 and BCKDH rs45500792 SNPs induces metabolic alterations that are not observed in subjects without either SNP.
The ability of alcohol extract of isolated soy protein to contribute to the hypochoesterolemic ef... more The ability of alcohol extract of isolated soy protein to contribute to the hypochoesterolemic effect mediated by the intake of soy protein was tested in gerbils. Gerbils were assigned to five different groups (n Å 8) and provided experimental diets for 28 d. Diets contained either casein or alcohol-washed isolated soy protein (ISP). The ISP diet was provided alone, or supplemented with one of three different levels of an alcohol extract of isolated soy protein contributing either 2.1, 3.6 or 6.2 mg isoflavones/g protein. Gerbils fed all of the soy-based diets had significantly lower (P õ 0.05) total cholesterol, LDL / VLDL cholesterol, and apolipoprotein B concentrations than those fed casein. The addition of the alcohol extract to ISP did not reduce serum cholesterol concentrations any further, but reduced hepatic apolipoprotein A-I mRNA levels (Põ 0.05) compared with casein- and ISP-fed groups. Levels of apolipoprotein E mRNA were not affected by diet. These data suggest that in ...
Archives of Medical Research, 2011
Background and Aims. Dietary fat plays a central role in the development of obesity. However, the... more Background and Aims. Dietary fat plays a central role in the development of obesity. However, the metabolic consequences of dietary fat can vary depending on their fatty acid composition. Therefore, the aim of the present work was to study the effect of the type and amount of dietary fat on the expression of genes controlling lipogenesis and fatty acid oxidation in the liver or adipose tissue of rats. Methods. The expression of hepatic or adipose tissue lipid metabolic genes from Sprague Dawley or Zucker fa/fa rats, respectively, was measured after chronic consumption of diets containing different types/amounts of dietary fats or after rats were adapted for 2 months to a high-fat Western diet and then fed different types and amounts of fats. Results. Each fat or oil in the diet regulated differentially the expression of transcription factors involved in lipogenesis and fatty acid oxidation as well as some of its target genes in liver. The expression of these genes after a chronic consumption of a high-fat Western diet was reestablished in the presence of less dietary fat and was dependent on the type of fat. In obese Zucker fa/fa rats, consumption of a high-fat diet repressed the expression of lipogenic, fatty acid oxidation and thermogenic genes in adipose tissue. Conclusions. Type of fat influences the expression of genes that are involved in lipid metabolism in liver and adipose tissue, but this response is repressed when the amount of dietary fat is excessive, diminishing the differences between each type of fat.
AJP: Renal Physiology, 2004
The mammalian kidney bumetanide-sensitive Na+-K+-2Cl− and thiazide-sensitive Na+-Cl− cotransporte... more The mammalian kidney bumetanide-sensitive Na+-K+-2Cl− and thiazide-sensitive Na+-Cl− cotransporters are the major pathways for salt reabsorption in the thick ascending limb of Henle's loop and distal convoluted tubule, respectively. These cotransporters serve as receptors for the loop- and thiazide-type diuretics, and inactivating mutations of corresponding genes are associated with development of Bartter's syndrome type I and Gitleman's disease, respectively. Structural requirements for ion translocation and diuretic binding specificity are unknown. As an initial approach for analyzing structural determinants conferring ion or diuretic preferences in these cotransporters, we exploited functional differences and structural similarities between Na+-K+-2Cl− and Na+-Cl− cotransporters to design and study chimeric proteins in which the NH2-terminal and/or COOH-terminal domains were switched between each other. Thus six chimeric proteins were produced. Using the heterologous ...
AJP: Renal Physiology, 2011
Obesity is a risk factor for the development of chronic kidney disease (CKD) and end-stage renal ... more Obesity is a risk factor for the development of chronic kidney disease (CKD) and end-stage renal disease. It is not clear whether the adoption of a high-protein diet in obese patients affects renal lipid metabolism or kidney function. Thus the aims of this study were to assess in obese Zucker fa/ fa rats the effects of different types and amounts of dietary protein on the expression of lipogenic and inflammatory genes, as well as renal lipid concentration and biochemical parameters of kidney function. Rats were fed different concentrations of soy protein or casein (20, 30, 45%) for 2 mo. Independent of the type of protein ingested, higher dietary protein intake led to higher serum triglycerides (TG) than rats fed adequate concentrations of protein. Additionally, the soy protein diet significantly increased serum TG compared with the casein diet. However, rats fed soy protein had significantly decreased serum cholesterol concentrations compared with those fed a casein diet. No signif...