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BMC Nephrology Jan 2015Phosphorus retention plays a pivotal role in the onset of mineral and bone disorders (MBD) in chronic kidney disease (CKD). Phosphorus retention commonly occurs as a...
Phosphorus retention plays a pivotal role in the onset of mineral and bone disorders (MBD) in chronic kidney disease (CKD). Phosphorus retention commonly occurs as a result of net intestinal absorption exceeding renal excretion or dialysis removal. The dietary phosphorus load is crucial since the early stages of CKD, throughout the whole course of the disease, up to dialysis-dependent end-stage renal disease.Agreement exits regarding the need for dietary phosphate control, but it is quite challenging in the real-life setting. Effective strategies to control dietary phosphorus intake include restricting phosphorus-rich foods, preferring phosphorus sourced from plant origin, boiling as the preferred cooking procedure and avoiding foods with phosphorus-containing additives. Nutritional education is crucial in this regard.Based on the existing literature, we developed the "phosphorus pyramid", namely a novel, visual, user-friendly tool for the nutritional education of patients and health-care professionals. The pyramid consists of six levels in which foods are arranged on the basis of their phosphorus content, phosphorus to protein ratio and phosphorus bioavailability. Each has a colored edge (from green to red) that corresponds to recommended intake frequency, ranging from "unrestricted" to "avoid as much as possible".The aim of the phosphorus pyramid is to support dietary counseling in order to reduce the phosphorus load, a crucial aspect of integrated CKD-MBD management.
Topics: Bone Diseases, Metabolic; Diet, Protein-Restricted; Directive Counseling; Food Additives; Humans; Kidney Failure, Chronic; Patient Education as Topic; Phosphorus, Dietary; Renal Dialysis; Renal Insufficiency, Chronic
PubMed: 25603926
DOI: 10.1186/1471-2369-16-9 -
Journal of Animal Science Jan 2023A total of 2,184 pigs (337 × 1,050, PIC; initially 12.4 ± 0.17 kg) were used in a 143-d study to evaluate the effects of feeding varying analyzed calcium to phosphorus...
Impact of dietary analyzed calcium to phosphorus ratios and standardized total tract digestible phosphorus to net energy ratios on growth performance, bone, and carcass characteristics of pigs.
A total of 2,184 pigs (337 × 1,050, PIC; initially 12.4 ± 0.17 kg) were used in a 143-d study to evaluate the effects of feeding varying analyzed calcium to phosphorus ratios (Ca:P) at two standardized total tract digestible (STTD) phosphorus to net energy ratios (STTD P:NE). Pens of pigs (26 pigs per pen) were assigned to 1 of the 6 dietary treatments in a 2 × 3 factorial with main effects of STTD P:NE and Ca:P ratio. Diets consisted of two levels of STTD P:NE; High (1.80, 1.62, 1.43, 1.25, 1.10, and 0.99 g STTD P/Mcal NE from 11 to 22, 22 to 40, 40 to 58, 58 to 81, 81 to 104, and 104 to 129 kg, respectively); or Low (75% of the High levels), and three analyzed Ca:P ratios (0.90:1, 1.30:1, and 1.75:1). There were 14 pens per treatment. Diets were corn-soybean meal-based and contained a constant phytase concentration within each dietary phase with levels decreasing throughout the trial (phases 1 through 3, 500 FTU/kg, assumed release of 0.13% STTD P; phase 4, 400 FTU/kg, assumed release of 0.11% STTD P; phase 5, 290 FTU/kg, assumed release of 0.09% STTD P; and phase 6, 210 FTU/kg, assumed release of 0.07% STTD P). Overall, there was a Ca:P × STTD P:NE interaction (P < 0.05) observed for average daily gain (ADG), feed efficiency (G:F), final body weight (BW), hot carcass weight (HCW), bone mineral density, bone mineral content, and bone-breaking strength. When feeding Low STTD P:NE levels, increasing the analyzed Ca:P ratio decreased (linear, P < 0.001) ADG final BW, HCW, and tended to worsen G:F, bone mineral density, and bone mineral content (linear, P < 0.10). However, when feeding High STTD P:NE levels, increasing the analyzed Ca:P ratio significantly improved bone mineral content and bone mineral density (linear, P < 0.05), and tended to improve ADG and final BW (linear, P < 0.10) and G:F (quadratic P < 0.10). Additionally, increasing the analyzed Ca:P ratio worsened ADG, G:F, and bone mineralization with Low STTD P:NE but had marginal impacts when adequate STTD P:NE was fed.
Topics: Animals; 6-Phytase; Calcium; Calcium, Dietary; Diet; Phosphorus, Dietary; Swine; Weight Gain
PubMed: 37226633
DOI: 10.1093/jas/skad168 -
Current Osteoporosis Reports Jun 2011Fibroblast growth factor 23 (FGF23), a hormone primarily produced in bone cells, targets the kidney to accelerate phosphate excretion into the urine and suppresses... (Review)
Review
Fibroblast growth factor 23 (FGF23), a hormone primarily produced in bone cells, targets the kidney to accelerate phosphate excretion into the urine and suppresses vitamin D synthesis, thereby inducing a negative phosphate balance. Excessive serum FGF23 due to hereditary disorders such as hypophosphatemic rickets leads to phosphate wasting and impaired bone mineralization. In contrast, deficiencies in FGF23 are associated with hyperphosphatemia, elevated 1,25(OH)(2)D(3), ectopic ossification in soft tissues, and defects in skeletal mineralization. Recent studies of human genetic disorders and genetically engineered mice, as well as the in vitro approaches, have clarified some mysteries in FGF23 regulation and its potential roles in bone modeling and remodeling, which are summarized in this review article.
Topics: Animals; Bone and Bones; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Humans; Hypophosphatemia; Mice; Mutation; Osteoblasts; Phosphorus, Dietary; Rickets; Vitamin D
PubMed: 21404002
DOI: 10.1007/s11914-011-0053-4 -
PloS One 2021The impact of dietary phosphorus (P) excess, especially on renal and cardiovascular health, has been investigated in several species, but little is known in dogs.
BACKGROUND
The impact of dietary phosphorus (P) excess, especially on renal and cardiovascular health, has been investigated in several species, but little is known in dogs.
OBJECTIVE
The aim of this study was to examine effects of different P sources on concentration and postprandial kinetics of selected parameters of P homeostasis in dogs.
METHODS
Eight beagles received one control diet (P 0.5% dry matter [DM]) and three high P diets (poultry meal, NaH2PO4, and KH2PO4; P 1.7% DM) for 18d. Urine samples were collected pre- and postprandially while faeces were collected quantitatively for 5d and analysed for minerals. On day 18, blood was sampled 1h pre- and 0.5, 1, 1.5, 2, 3, 5 and 7h postprandially.
RESULTS
Pi (KH2PO4, NaH2PO4) but not organic P caused an increased apparent P digestibility and significantly influenced kinetics of serum FGF23, parathyroid hormone, P, CrossLaps and bonespecific alkaline phosphatase, demonstrating a disrupted calcium (Ca) and P homeostasis with potential harm for renal, cardiovascular and skeletal health.
CONCLUSIONS
Results of feeding Pi to dogs indicate distinct disturbances of Ca and P metabolism, in contrast to organic sources. The use of Pi in food can therefore not be considered as safe. Further research, especially on dose and long-term effects, is warranted.
Topics: Animals; Dogs; Feces; Homeostasis; Organic Chemicals; Phosphorus; Phosphorus, Dietary; Postprandial Period
PubMed: 33606750
DOI: 10.1371/journal.pone.0246950 -
In Vivo (Athens, Greece) 2019Hyperphosphatemia is a serious complication in patients with chronic kidney disease (CKD), and is associated with more rapid progression as well as higher risk of... (Review)
Review
Hyperphosphatemia is a serious complication in patients with chronic kidney disease (CKD), and is associated with more rapid progression as well as higher risk of mortality, and higher rate of cardiovascular disease accidents. CKD patients are usually advised to adopt a low phosphate diet in addition to phosphate-lowering medications, if necessary. However, there is a lack of awareness of the dietary sources of phosphate, especially hidden phosphate intake from phosphate additives in processed foods and carbonated beverages. Appropriate nutritional education could be an effective solution in reducing phosphate toxicity without introducing an additional pill burden or malnutrition.
Topics: Cardiovascular Diseases; Fibroblast Growth Factor-23; Humans; Hyperphosphatemia; Malnutrition; Phosphorus, Dietary; Renal Insufficiency, Chronic; Risk Factors
PubMed: 30587596
DOI: 10.21873/invivo.11432 -
Poultry Science Nov 1993Two experiments were conducted to evaluate the effect of dietary phytase and increasing levels of available phosphorus (P(av)) on the growth performance and phosphorus... (Review)
Review
Two experiments were conducted to evaluate the effect of dietary phytase and increasing levels of available phosphorus (P(av)) on the growth performance and phosphorus metabolism of broiler chicks. In both experiments, graded levels of P provided by dicalcium phosphate and of phytase were added to a low-P corn-soybean meal basal diet. In Experiment 1, diets providing .21, .29, .37, and .44% P(av) without phytase; .21% P(av) plus .05, .10, or .30% phytase; and .29% P(av) plus .10% phytase were each fed to four groups of seven chicks, 3 days of age. In Experiment 2, diets providing P(av) levels of .32, .38, and .44% and phytase levels of .5, 1.0, and 1.5% (250, 500, and 750 units/kg) in a factorial arrangement were each fed to four groups of eight chicks, 5 days of age. In Experiment 1, increasing dietary P(av), but not phytase, increased feed intake, weight gain, feed conversion, plasma inorganic P, tibia and toe ash, and tibia breaking strength (P < or = .05). Plasma inorganic P responded quadratically to increasing dietary phytase. In Experiment 2, feed intake and weight gain were increased by elevating the level of P(av), but not by phytase. Toe and tibia ash and plasma inorganic P were increased by dietary phytase and increasing levels of P(av) (P < or = .01). Tibia breaking strength was improved (P < or = .05) by dietary phytase but not by increasing levels of P(av). The P excretion was elevated (P < or = .01) by increasing levels of P(av) and was decreased by supplemental phytase (P < or = .05).(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: 6-Phytase; Animals; Calcification, Physiologic; Chickens; Eating; Male; Phosphorus; Phosphorus, Dietary; Weight Gain
PubMed: 8265499
DOI: 10.3382/ps.0722106 -
Clinical Journal of the American... Jul 2018Twenty-four-hour urine phosphorus is commonly used as a surrogate measure for phosphorus intake and absorption in research studies, but its reliability and accuracy are...
BACKGROUND AND OBJECTIVES
Twenty-four-hour urine phosphorus is commonly used as a surrogate measure for phosphorus intake and absorption in research studies, but its reliability and accuracy are unproven in health or CKD. This secondary analysis sought to determine the reliability and accuracy of 24-hour urine phosphorus as a biomarker of phosphorus intake and absorption in moderate CKD.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS
Eight patients with stage 3-4 CKD participated in 2-week balance studies with tightly controlled phosphorus and calcium intakes. Thirteen 24-hour urine collections per patient were analyzed for variability and reliability of 24-hour urine phosphorus and phosphorus-to-creatinine ratio. The accuracy of 24-hour urine phosphorus to predict phosphorus intake was determined using a published equation. The relationships of 24-hour urine phosphorus with phosphorus intake, net absorption, and retention were determined.
RESULTS
There was wide day-to-day variation in 24-hour urine phosphorus within and among subjects (coefficient of variation of 30% and 37%, respectively). Two 24-hour urine measures were needed to achieve ≥75% reliability. Estimating dietary phosphorus intake from a single 24-hour urine resulted in underestimation up to 98% in some patients and overestimation up to 79% in others. Twenty-four-hour urine phosphorus negatively correlated with whole-body retention but was not related to net absorption.
CONCLUSIONS
From a sample of eight patients with moderate CKD on a tightly controlled dietary intake, 24-hour urine phosphorus was highly variable and did not relate to dietary phosphorus intake or absorption, rather it inversely related to phosphorus retention.
Topics: Biomarkers; Diet Therapy; Female; Humans; Male; Middle Aged; Monitoring, Physiologic; Phosphorus; Phosphorus, Dietary; Renal Insufficiency, Chronic
PubMed: 29921736
DOI: 10.2215/CJN.00390118 -
Asia Pacific Journal of Clinical... 2011Phosphorus and calcium are essential for bone health. There is a concern that a low calcium/phosphorus intake ratio resulting from low calcium intake coupled with high...
Phosphorus and calcium are essential for bone health. There is a concern that a low calcium/phosphorus intake ratio resulting from low calcium intake coupled with high phosphorus intake may have a negative effect on bone mineral status, especially in Western countries. The objective of this study was to examine cross-sectionally the influence of habitual phosphorus and calcium intake and the calcium/phosphorus intake ratio on the bone mineral density (BMD) in 441 young Japanese women (aged 18-22) whose calcium/phosphorus intake ratio was assumed to be lower than young Western women. We also ascertained the relationship between dietary intake and serum or urinary measurements of phosphorus and calcium. Parathyroid hormone (PTH) and 25-hydroxy vitamin D (25(OH)D) were also examined for 214 of the 441 subjects. Phosphorus and calcium intake and the calcium/phosphorus intake ratio had significant positive correlations with urinary phosphorus. Calcium intake and the calcium/phosphorus intake ratio independently had positive and significant associations with BMD in the distal radius adjusted for postmenarcheal age, body mass index, and physical activity. There were no significant associations with BMD in the lumbar spine and femoral neck. These results indicate that in young Japanese women, phosphorus intake did not have a significantly negative effect on bone mineral density, and calcium intake and calcium/phosphorus intake ratio had a small but significant association only in a site-specific manner with BMD.
Topics: Absorptiometry, Photon; Adult; Biomarkers; Bone Density; Calcium, Dietary; Cross-Sectional Studies; Diet; Feeding Behavior; Female; Femur Neck; Forearm; Humans; Japan; Lumbar Vertebrae; Parathyroid Hormone; Phosphorus, Dietary; Students; Vitamin D; Young Adult
PubMed: 21859660
DOI: No ID Found -
Journal of Animal Science Dec 2021An experiment was conducted to test two hypotheses: 1) reducing dietary Ca and P reduces gastric pH and diarrhea in weanling pigs; 2) negative effects of low Ca and P on...
Increased microbial phytase increased phytate destruction, plasma inositol, and feed efficiency of weanling pigs, but reduced dietary calcium and phosphorus did not affect gastric pH or fecal score and reduced growth performance and bone ash.
An experiment was conducted to test two hypotheses: 1) reducing dietary Ca and P reduces gastric pH and diarrhea in weanling pigs; 2) negative effects of low Ca and P on pig growth performance may be overcome if phytase is added to the diets. A total of 320 weanling pigs (6.35 ± 0.87 kg) were allotted to eight corn-soybean meal-based diets in a randomized complete block design with five pigs per pen. Two phase 1 (days 1 to 14) control diets containing 100 or 50% of total Ca and digestible P relative to the requirement, and six diets in which 500, 2,000, or 16,000 units of phytase/kg feed (FTU) were added to each control diet were formulated. Phytase was assumed to release 0.16% total Ca and 0.11% digestible P. Common diets were fed in phases 2 (days 15 to 27) and 3 (days 28 to 42). Growth performance data were recorded within each phase. Data for fecal scores and gastrointestinal pH were recorded for phase 1. Colon content (day 14), the right femur (days 14 and 42), and blood samples (days -1, 14, 27, and 42) were collected from one pig per pen. In phase 1, reducing Ca and P did not reduce gastric pH or fecal score, but pigs fed the 50% diets had reduced (P < 0.05) average daily gain (ADG) and average daily feed intake (ADFI) compared with pigs fed the 100% diets. In both 50% and 100% diets, phytase above 500 FTU increased (P < 0.05) gain:feed ratio (G:F) and tended (P < 0.10) to reduce gastric pH of pigs. From days 1 to 42, pigs fed the 50% diets tended (P < 0.10) to have reduced ADG and ADFI compared with pigs fed the 100% diets, but among the 100% diets, pigs tended (P < 0.10) to have a linear increase in G:F as phytase level increased. Pigs fed the 50% diets had reduced (P < 0.05) concentrations of inositol phosphate esters (IP) in the colon and reduced bone ash (days 14 and 42) compared with pigs fed the 100% diets. Phytase did not affect bone ash or most blood metabolites. Concentrations of IP in the colon decreased, whereas plasma inositol increased (d 14; P < 0.05) in pigs fed diets with phytase (≥ 500 FTU). In pigs fed the 100% diets, IP in the colon linearly decreased (P < 0.05), but plasma inositol linearly increased (P < 0.05) with increasing levels of phytase. In conclusion, reducing Ca and P in diets for weanling pigs did not influence gastric pH or fecal score, but compromised growth performance and bone ash. However, regardless of dietary Ca and P, high doses of phytase increased phytate degradation and inositol absorption, which consequently increased G:F of pigs.
Topics: 6-Phytase; Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Calcium, Dietary; Diet; Dietary Supplements; Digestion; Hydrogen-Ion Concentration; Inositol; Minerals; Phosphorus, Dietary; Phytic Acid; Swine
PubMed: 34747490
DOI: 10.1093/jas/skab333 -
Poultry Science Jul 2018In mammals, fibroblast growth factor 23 (FGF23) regulates phosphate homeostasis in kidney by binding α-Klotho, a coreceptor of FGF23. FGF23 mRNA is highly expressed in...
In mammals, fibroblast growth factor 23 (FGF23) regulates phosphate homeostasis in kidney by binding α-Klotho, a coreceptor of FGF23. FGF23 mRNA is highly expressed in bone and slightly expressed in liver, and is regulated by dietary phosphorus. Little is known about distribution and regulation of FGF23 mRNA in avian lineage. The expression of FGF23 and its coreceptor α-Klotho in chicken and embryo were investigated by real-time quantitative PCR. The effect of dietary phosphorus on FGF23 expression was measured. 36 laying hens at 25 wk were randomly assigned to three dietary available phosphorus (AP) treatments for 11 days: 0.15% AP (LP), 0.40% AP (MP), and 0.80% AP (HP). We first cloned the full coding sequence of FGF23 by the reverse transcription PCR from chicken liver and calvaria. Bioinformatics analysis indicated that the deduced amino acid sequence was 57-87% identical to FGF23 of other species. In adult chicken FGF23 mRNA was expressed at unexpected higher level in liver than other tissues evaluated, including calvaria, femur, tibia, medullary bone, brain, spleen, duodenum, jejunum, ileum, heart and kidney (P < 0.0001), and α-Klotho was expressed at highest level in kidney. However, in 18-d chicken embryos, FGF23 mRNA level was much higher in tibia than in liver, heart and jejunum (P < 0.0001). Chickens at 2, 25, 50 and 80 wk had higher FGF23 expression in liver than 18-d chicken embryos, whereas chickens at 25 wk had lower FGF23 expression in tibia than 18-d chicken embryos and 2-wk-old chickens. HP diets significantly increased serum inorganic phosphorus level (P < 0.001) and FGF23 expression (P < 0.05) in bone tissue compared with LP diets, however, FGF23 mRNA abundance in liver was not changed significantly (P > 0.05) by dietary phosphorus treatments. In conclusion, FGF23 mRNA expression pattern in chicken was clearly different from that in mammals and dietary phosphorus regulated the expression of FGF23 in a tissue-specific way.
Topics: Amino Acid Sequence; Animals; Avian Proteins; Base Sequence; Bone and Bones; Chickens; Female; Fibroblast Growth Factor-23; Fibroblast Growth Factors; Gene Expression Profiling; Gene Expression Regulation; Liver; Mice; Phosphorus, Dietary; RNA, Messenger; Random Allocation; Sequence Alignment; Transcriptome
PubMed: 29688456
DOI: 10.3382/ps/pey092