Phosphorus Metabolism Research Articles

Non-classical hormones from the fibroblast growth factor family

Fibroblast growth factors (FGFs) are a group of signaling molecules named for their ability to promote the growth and proliferation of fibroblasts and various other cell types. Typically, FGFs exert their effects locally by binding to receptors within the tissues where they are synthesized. However, certain members of this family, such as FGF 19, FGF 21, and FGF 23, diverge from this pattern. Following synthesis, these FGFs enter the bloodstream and act on distant organs and tissues by binding to their receptors and associated cofactors, thereby classified as non-classical hormones within the FGF family.The biological functions of FGFs are diverse and contingent upon the specific receptors and cofactors involved in their signaling pathways. For instance, FGF 19 and FGF 21 play crucial roles in regulating glucose and lipid metabolism, whereas FGF 23 primarily influences phosphorus metabolism. Given their varied roles, FGFs present promising targets for therapeutic interventions and drug development.This review aims to consolidate current understanding of FGF family hormones, elucidating their biological impacts and exploring their potential applications as therapeutic targets.

Phosphorus removal performance of Sulfide-Based autotrophic denitrification process

Sulfide-based Autotrophic Denitrification (SAD) Process can simultaneous remove sulfurous and nitrogenous pollutants, showing a promising prospect. Beyond our expectation, it also has an efficient phosphorus (P) removal performance. The operation results demonstrated that when the influent concentration of nitrate, sulfide and phosphate was 80.55 ± 2.98 mg N/L, 380.15 ± 20.83 mg S/L and 47.70 ± 4.35 mg P/L respectively, their removal efficiency was 87.63 ± 3.12 %, 99.61 ± 1.02 % and 85.38 ± 4.07 % at the HRT of 8.8 h. However, the phosphorus removal performance disappeared once the effluent pH dropped below 8.0. The random forest regression model revealed that effluent pH had the most significant impact on phosphorus removal performance. This finding was corroborated by a mathematical model that related the phosphate removal load to effluent pHs. The combination of batch test, Standard Measurements and Testing (SMT) and X-Ray Diffraction (XRD) method revealed that the phosphorus removal performance of SAD process came from the synergies of biological phosphorus removal (29.71 ± 3.21 %) and bio-induced phosphate precipitation (70.29 ± 3.21 %). The analysis of key functional genes coding for nitrogen, sulfur and phosphorus metabolism offered an explanation for their metabolic pathways especially the phosphorus removal pathway. The study would provide some new information for the development of SAD process.

A phosphate starvation induced small RNA promotes Bacillus biofilm formation

Currently, almost all known regulators involved in bacterial phosphorus metabolism are proteins. In this study, we identified a conserved new small regulatory RNA (sRNA), named PhoS, encoded in the 3’ untranslated region (UTR) of the phoPR genes in Bacillus velezensis and B. subtilis. Expression of phoS is strongly induced upon phosphorus scarcity and stimulated by the transcription factor PhoP. Conversely, PhoS positively regulates PhoP translation by binding to the ribosome binding site (RBS) of phoP mRNA. PhoS can promote Bacillus biofilm formation through, at least in part, enhancing the expression of the matrix-related genes, such as the eps genes and the tapA-sipW-tasA operon. The positive regulation of phoP expression by PhoS contributes to the promoting effect of PhoS on biofilm formation. sRNAs regulating biofilm formation have rarely been reported in gram-positive Bacillus species. Here we highlight the significance of sRNAs involved in two important biological processes: phosphate metabolism and biofilm formation.

Analysis of Bone Phenotype Differences in MEN1-Related and Sporadic Primary Hyperparathyroidism Using 3D-DXA

Background: The rarity and variability of MEN1-related primary hyperparathyroidism (mPHPT) has led to contradictory data regarding the bone phenotype in this patient population. Methods: A single-center retrospective study was conducted among young age- and sex-matched patients with mPHPT and sporadic hyperparathyroidism (sPHPT). The main parameters of calcium–phosphorus metabolism, bone remodeling markers, and bone mineral density (BMD) measurements were obtained during the active phase of hyperparathyroidism before parathyroidectomy (PTE) and 1 year after. Trabecular Bone Score (TBS) and 3D-DXA analysis of the proximal femur were used to evaluate the differences in bone architecture disruption between groups. Results: Patients with mPHPT had significant lower preoperative BMD compared to sPHPT at lumbar spine—LS (p = 0.002); femur neck—FN (p = 0.001); and total hip—TH (p = 0.002). 3D-DXA analysis showed the prevalence of cortical rather than trabecular bone damage in mPHPT compared to sPHPT: cortical thickness (p < 0.001); cortical surface BMD (p = 0.001); cortical volumetric BMD (p = 0.007); and trabecular volumetric BMD (p = 0.029). One year after, PTE DXA and 3D-DXA parameters were similar between groups, while 3D-visualisation showed more extensive regeneration in cortical sBMD and cortical thickness in mPHPT. Conclusions: mPHPT is associated with lower preoperative BMD values with predominant architecture disruption in the cortical bone. The absence of differences in DXA and 3D-DXA parameters 1 year after PTE between mPHPT/sPHPT combined with significantly lower BMD in mPHPT at the initial stage may indicate faster bone recovery after surgery in mPHPT than in sPHPT.

Factors associated with carotid artery calcification in the general working-age population

Aim. To study factors associated with carotid artery calcification as an atherosclerotic marker in the general working-age population.Material and methods. The data of a representative ESSE-RF sample aged 25-64 years (n=1412) were studied. They underwent standard cardiology screening and assessment of carotid plaque (CP) characteristics using ultrasound. All respondents signed an informed consent to participate in the study. The association analysis included socio-demographic, anamnestic, laboratory, and ultrasound characteristics. Univariate and multivariate statistics were used.Results. The prevalence of detection of calcified CP (cCP) was 5,4% — 7,8% in men and 3,7% in women (odds ratio (OR)=2,2; p=0,001). The probability of cCP detection was associated with following factors: male sex (OR=3,9; p<0,001), age (OR=1,2; p<0,001), total cholesterol (women, OR=1,7; p=0,001), history of thyrotoxicosis (OR=2,1; p=0,034), osteoporosis (OR=2,6; p=0,009), and smoking (OR=1,8; p=0,046). The odds that the detected plaque would be calcified were higher in individuals in the 4th quartile of mean plaque size distribution (OR=3,8; p<0,001) and in the presence of the following factors: male sex (OR=1,9; p=0,031), age ≥55 years (OR=4,3; p<0,001), osteoporosis (OR=3,2; p=0,007), high-density lipoprotein cholesterol level ≥1,3 mmol/l (OR=2,0; p=0,025).Conclusion. The obtained data indicate an association of carotid calcification with both traditional cardiovascular risk factors and systemic diseases associated with impaired calcium and phosphorus metabolism (thyrotoxicosis, osteoporosis). The study results can be useful in practical healthcare, research, and developing preventive technologies.

Grazer‐induced toxin production is energetically costly and significantly reduces growth of cylindrospermopsin‐producing cyanobacteria

AbstractToxins have been proposed as a defense mechanism for phytoplankton against zooplankton grazing. However, the associated costs are not understood. Here, we aim to reveal the costs in terms of both physiological and molecular responses in the cylindrospermopsin (CYN)‐producing cyanobacterium Raphidiopsis raciborskii. Exposure of R. raciborskii to Daphnia magna resulted in a significant increase in its CYN cell quota which was grazer cell density‐dependent, indicating an inducible effect on CYN production. A negative and significant relationship between cellular growth rate and CYN production suggested a growth‐defense trade‐off, highlighting the costly nature of toxin production. Despite strong transcriptional responses (121 differentially expressed genes) in R. raciborskii under grazing pressure, the CYN gene cluster remained largely unaffected, implying post‐transcriptional regulation of CYN biosynthesis. Significant variation was observed in transcripts for phosphorus metabolism and photosynthesis‐related genes, and evidenced that energy (ATP) metabolic processes were stimulated. This study is the first to demonstrate the high energy requirements for CYN production and provide insight into the molecular basis underlying the costs of toxin production.

Advances in the mechanisms of vascular calcification in chronic kidney disease.

Vascular calcification (VC) is common in patients with advanced chronic kidney disease (CKD).A series of factors, such as calcium and phosphorus metabolism disorders, uremic toxin accumulation, inflammation and oxidative stress and cellular senescence, cause osteoblast-like differentiation of vascular smooth muscle cells, secretion of extracellular vesicles, and imbalance of calcium regulatory factors, which together promote the development of VC in CKD. Recent advances in epigenetics have provided better tools for the investigation of VC etiology and new approaches for finding more accurate biomarkers. These advances have not only deepened our understanding of the pathophysiological mechanisms of VC in CKD, but also provided valuable clues for the optimization of clinical predictors and the exploration of potential therapeutic targets. The aim of this article is to provide a comprehensive overview of the pathogenesis of CKD VC, especially the new advances made in recent years, including the various key factors mentioned above. Through the comprehensive analysis, we expect to provide a solid theoretical foundation and research direction for future studies targeting the specific mechanisms of CKD VC, the establishment of clinical predictive indicators and the development of potential therapeutic strategies.

The effect of empagliflozin (sodium-glucose cotransporter-2 inhibitor) on osteoporosis and glycemic parameters in patients with type 2 diabetes: a quasi-experimental study.

Diabetic osteoporosis (DOP) is a metabolic disease that occurs in patients with diabetes due to insufficient insulin secretion. This condition can lead to sensory neuropathy, nephropathy, retinopathy, and hypoglycemic events, which can increase the risk of fractures. This study aimed to assess the effectiveness of Empagliflozin, a sodium-glucose cotransporter-2 (SGLT-2) inhibitor, in treating diabetic osteoporosis (DOP) and preventing fractures. This quasi-experimental study enrolled 100 patients with diabetic osteoporosis from February 2023 to February 2024. Participants were randomly assigned to an intervention group (n = 50) and a control group (n = 50). The intervention group received Empagliflozin in combination with symptomatic treatment, while the control group received only symptomatic treatment. The treatment duration was six months. Fasting blood glucose (FBG), 2-hour postprandial blood glucose (2h PG), glycosylated hemoglobin A1c (Hb A1c), bone mineral density (BMD), serum phosphorus and calcium concentration were measured after the intervention and the incidence of fracture was followed up for 12 months. The data were analyzed using SPSS 23. Descriptive statistics (mean, standard deviation, and percentage) and analytical methods (t test, Chi square) were also used to analyze the data. After six months of treatment, the intervention group exhibited significantly lower levels of FBG (P < 0.001), 2h-PG (P = 0.001), and HbA1c (P < 0.001) than the control group. Additionally, bone mineral density, serum phosphorus, and calcium levels were significantly higher in the intervention group (P < 0.001). After a 12-months follow-up, the incidence of fractures in the intervention group was 2%, while it was 16.33% in the control group (P < 0.05). Empagliflozin, when combined with symptomatic treatment, demonstrates a positive clinical effect in patients with diabetic osteoporosis. The treatment effectively improves blood glucose metabolism, bone mineral density, and phosphorus and calcium metabolism, ultimately leading to a significant reduction in the incidence of fracture.

Extended photoperiods enhance the production and water treatment performance of algal-bacterial bioflocs from aquaculture wastewater

Reducing pollution and converting wastewater nutrients into useful biomass are major challenges of intensive aquaculture. We investigated the nitrogen and phosphorus metabolism, nutrient composition, and microbial community of algal-bacterial bioflocs (ABBs) produced under glucose addition and different photoperiods. This biomass was used for aquaculture wastewater treatment for 18 days. ABBs produced under longer photoperiods were smaller and more numerous, which facilitated nitrogen recovery and reduced nitrogen loss. Additionally, nitrogen and phosphorus-metabolizing enzyme activities, as well as the activity of overall microorganisms were positively correlated with the light duration. The removal rates of COD (96.89 %), DTN (93.57 %), and DTP (93.67 %) from wastewater by ABBs were highest when the photoperiod was 16L:8D during the production period. Moreover, the crude protein content (41.77 ± 0.11 %) was highest under a photoperiod of 12L:12D, and the rich amino acid and fatty acid profile of the ABB under this photoperiod enhanced its utility as a feed additive for aquaculture species. The high-throughput sequencing analysis revealed a high abundance of Hydrogenophaga at the genus level, highlighting its denitrification capacity of ABBs under the 16L:8D photoperiod. Redundancy analysis (RDA) demonstrated that photoperiod, as a key driver in the formation of microbial communities in ABBs, exerted a direct influence on water treatment efficiency and nutrient accumulation. This study provides new insights into the effects of photoperiod on the properties of ABBs, which has implications for the treatment and subsequent application of aquaculture wastewater.

Role and mechanism of Actein on condylar bone metabolism in APOE deletion-induced osteoporotic mice

AimsTo investigate the effects of Actein from Cimicifugae Rhizoma on condylar bone and cartilage in APOE deletion-induced osteoporotic mice, and to preliminarily explore the underlying mechanism. MethodsSixty 8-week-old female mice were used, which underwent APOE−/− and ovariectomy procedures, followed by oral administration of Actein (15 mg/kg) and Atorvastatin Calcium (AC, 3 mg/kg) for eight weeks. Body weight, uterine weight, and systemic indexes related to bone metabolism and lipid metabolism were assessed in each group. Changes in condylar bone histomorphometric parameters were evaluated using Micro-CT. Morphological changes in the condyle were observed with Hematoxylin-Eosin (H&E), Safranin O/Fast Green, and Alcian Blue Hematoxylin/Orange G (ABH/OG) staining, with OARSI pathology scoring performed. Sirius red staining and immunofluorescence were used to determine the expression levels of Collagen I (Col I) and Collagen III (Col III) in bone matrix, and Col II in cartilage matrix. Immunohistochemistry assessed the relative expression levels of ALP and proteins associated with the Wnt/β-catenin/RUNX2 signaling pathway. ResultsAPOE−/− exacerbates ovariectomy -induced osteoporosis (OP) in condylar of mice. Actein and AC significantly reversed OP, improved bone mineral density (BMD), increased bone microarchitecture, and restored abnormal calcium and phosphorus metabolism in the blood and urine. Morphologically, APOE−/− and ovariectomy reduced condylar cartilage thickness, disrupted chondrocyte arrangement, chondrocyte cleavage, and clustered aggregation, resembling osteoarthritis (OA)-like changes. Actein and AC partially restored the disrupted chondrocyte arrangement, smoothed chondrocyte cleavage, and up-regulated the levels of chondrocyte matrix (Col II, aggrecan) and bone matrix (Col III, ALP). Actein reversed the OA process, potentially through the Wnt/β-catenin/RUNX2 signaling pathway. ConclusionAPOE−/− and ovariectomy induced OP, leading to OA-like lesions in condylar of mice. Actein promoted cartilage repair and trabecular bone recovery by increasing extracellular matrix synthesis (Col II, Col III, aggrecan), reversing the OA process, possibly through the Wnt/β-catenin/RUNX2 signaling pathway.

Responses of SNEDPR-AGS system under long-term exposure of polyethylene terephthalate microplastics for treating low C/N wastewater: Granular effect and microbial structure

The removal of nutrients in sewage treatment plants can be significantly impacted by carbon limitations, especially for treating low carbon to nitrogen ratio (C/N) wastewater, which can markedly increase operational costs. Simultaneous nitrification, endogenous denitrification, and phosphorus removal combined with aerobic granular sludge (SNEDPR-AGS) has emerged as one of the optimal processes for treating low C/N wastewater owing to its high carbon utilization efficiency; however, the long-term effect of microplastics (MPs) on this system remains unclear. This study investigated the granular effect and microbial response of an SNEDPR-AGS system for treating low C/N wastewater under long-term exposure (180 d) to polyethylene terephthalate microplastics (PET-MPs). The results showed that the integrity of the AGS structure was disrupted significantly as the PET-MP concentration increased, with clear AGS cracks appearing on days 180, 124, and 74 after exposure to 1, 10, and 100 mg/L of PET-MPs, respectively. Additionally, the addition of PET-MPs also inhibited denitrification and phosphorus removal due to a decrease in the relative abundance of functional genes (napAB, nirK/nirS, ppk1, ppk2, and ppx). Notably, both chemometric and high-throughput sequencing results indicated that the metabolic form of the system would shift from a polyphosphate-accumulating metabolism to a glycogen-accumulating metabolism. The reason may be that PET-MP stress inhibited the relative abundance of functional genes related to carbon, glycogen, phosphorus, and energy metabolism pathways in Candidatus Accumulibacter and Dechloromonas, but promoted their relative abundance of Candidatus Competibacter. Flow cytometry and molecular docking simulations have also demonstrated the direct toxic effects of PET-MPs on the SNEDPR-AGS system. The biological enhancement and functional recovery of damaged SNEDPR-AGS systems must be further investigated in future studies.

Responses of laying performance, eggshell quality, calcium, and phosphorus metabolism to feeding patterns and dietary available phosphorus levels in aged laying hens

Responses of laying performance, eggshell quality, calcium, and phosphorus metabolism to feeding patterns and dietary available phosphorus levels in aged laying hens

Effect of Substituting of Amino Acids Residues Ser-911 and Thr-912 in the Plasma Membrane H+-ATPase of Yeast &lt;i&gt;Saccharomyces cerevisiae&lt;/i&gt; on Its Activity and Distribution of Polyphosphates

The vital enzyme of yeast metabolism, plasma membrane H+-ATPase (PMA1), is phosphorylated during folding and functioning. The main phosphorylation sites are Ser911 and Thr-912 in the C-terminal regulatory domain. The work used wild and mutant forms of the enzyme with substitutions of these amino acid residues with Ala or Asp to determine their role in the functioning of the ATPase and the distribution of polyphosphates (polyP) by fractions. Growth parameters, ATP content, and in situ polyP distribution were determined on whole cells. To determine the ATPase activity in vitro, plasma membranes containing wild-type enzyme and mutant forms were isolated. Mutants S911D, T912D and S911D/T912A had ATPase activity close to the wild type; mutant S911A had increased activity. The growth rate of strains S911D, T912D and S911D/T912A was 2.0‒3.0 times lower than that of the wild type, and the growth rate of S911A was close to the wild type. Mutations S911D and S911D/T912A caused a decrease in ATP content by 2.0‒2.5 times. All substitutions affected the distribution of polyP by fractions. The effect depended on the chemical nature of the substitution: in the case of replacement with Asp, which changes the type of phosphosite, there was a decrease in the polyR1 fraction and an increase in the polyR2 fraction; when replaced with Ala, which removes phosphosite, the effect was the opposite. The content of the polyP3 fraction increased in all mutants. The data indicate that the residues of Ser911 and Thr-912 are important not only for the normal functioning of the PMA of H+-ATPase, but also for the regulation of phosphorus and energy metabolism.

Contrasting but interconnecting metatranscriptome between large buoyant and small suspended particles during cyanobacterial blooming in the large shallow eutrophic Taihu Lake

Large cyanobacterial colonies as visible particles floating on the water surface provide different microbial niches from small particles suspended in the water column in eutrophic freshwaters. However, functional potential differences among microbes colonizing on these contrasting particles are not well understood. Here, the metatranscriptome of microbes inhabiting these two kinds of particles during cyanobacterial bloom (dominated by Microcystis spp.) was analyzed and compared. Community compositions of active bacteria associated with small suspended particles (SA, aggregates dominated by small cyanobacteria colonies, other algae and detritus, etc.) were much more diverse than those associated with large buoyant cyanobacterial colonies (LA), but functional diversity was not significantly different between them. Transcripts related to phosphorus and nitrogen metabolism from Proteobacteria, and respiration from Bacteroidetes were enriched in LA, whereas many more pathways such as photosynthesis from Cyanobacteria, cofactors, and protein metabolism from all dominant phyla were enriched in SA. Nevertheless, many transcripts were significantly correlated within and between LA and SA. These results indicated interconnection of bacteria between LA and SA. Moreover, many transcripts in SA were significantly correlated with transcripts from cyanobacterial phycobilisome in LA, indicating that bacterial metabolism in SA may influence cyanobacterial biomass in LA. Thus, the prediction of cyanobacterial blooms by bacterial activity in SA may be possible when there is no visible bloom on the water surface.

The microRNA399d-PHOSPHATE2 module alters rice sensitivity to rice ragged stunt virus by manipulating phosphate uptake.

Rice (Oryza sativa L.) production frequently faces threats from biotic and abiotic stressors, with rice ragged stunt virus (RRSV) as a substantial biotic factor. The relationship between inorganic phosphorus (Pi) content and susceptibility to RRSV is crucial yet poorly understood. This study investigates how phosphorus metabolism influences rice resistance to RRSV, focusing on genetic manipulations that modulate this relationship. The RRSV infection increased phosphate (Pi) content in the aerial parts of rice plants by enhancing Pi uptake and transport. Furthermore, the upregulation of microRNA399d (miR399d) and the suppression of its target gene OsPHOSPHATE2 (OsPHO2) enhanced Pi accumulation, increasing rice susceptibility to RRSV infection. Additionally, elevated Pi levels, which are associated with altered ROS dynamics, reduced ROS activity and potentially dampened the plant's innate immune response to viral infection. The miR399d-PHO2 module was identified as pivotal in mediating phosphate uptake and influencing susceptibility to RRSV through modulations in the phosphorus and ROS pathways. This study shed light on the regulatory mechanisms of phosphorus nutrition in rice, revealing a critical interaction between phosphorus metabolism, ROS dynamics, and viral defense. The findings suggest potential strategies for manipulating Pi levels to enhance plant resistance against viruses, opening avenues for agricultural improvements and disease management in rice.

Variation and functional profile of gut bacteria in the scarab beetle, Anomala dimidiata, under a cellulose-enriched microenvironment

This study utilized cultivable methods and 16 S amplicon sequencing to compare taxonomic profiles and functional potential of gut bacteria in the scarab beetle, Anomola dimidiata, under cellulose-enriched conditions. Eight culturable cellulolytic gut bacteria were isolated from the midgut and hindgut of the scarab larvae, respectively. 16 S amplicon sequencing evinced that the most represented taxonomic profiles at phylum level in the fermentation chamber and midgut were Bacillota (71.62 and 56.76%), Pseudomonadota (22.66 and 36.89%) and Bacteroidota (2.7 and 2.81%). Bacillota (56.74 and 91.39%) were significantly enriched in the midgut with the addition of cellulose. In contrast, Bacillota and Psedomonadota were significantly enriched in the fermentation chamber. Carbohydrate metabolism was up-regulated in the midgut, while nitrogen and phosphorus metabolism were up-regulated in the fermentation chamber, suggesting these symbionts’ possible metabolic roles to the host. An analysis of total cellulases as well as amplicon sequence variants indicated that the gut bacteria belonging to Acinetobacter, Bacillus, Brucella, Brevibacillus, Enterobacter, Lysinibacillus and Paenibacillus are involved in nutrition provisioning. These results have provided additional insights into the gut bacteria associated with cellulose digestion in A. dimidiata and created a platform for bioprospecting novel isolates to produce biomolecules for biotechnological use, besides identifying eco-friendly targets for its management.

Diurnal variation of serum phosphorus concentrations in intact male adult domestic cats.

Monitoring serum phosphorus concentrations is crucial in the management of chronic kidney disease in cats. The diurnal variation of serum phosphorus concentration may affect clinical assessment. Characterize the diurnal variation of serum phosphorus concentration in cats and determine the associations between changes in serum phosphorus concentration and several metabolites of phosphorus metabolism. Six apparently healthy, intact male, specific-pathogen-free cats were housed in a photoperiod, humidity, and temperature-controlled facility. Blood sampling was performed hourly for 24 hours to obtain the serum concentrations of phosphorus, ionized calcium, parathyroid hormone, and calcidiol. Results were analyzed using linear mixed-effect models to determine the significance of diurnal variation and associations between serum phosphorus concentrations and other metabolites over time. Diurnal variation in serum phosphorus concentration was noted with an apex around 11:00 followed by gradually declining concentrations to reach the nadir around 23:00. The serum phosphorus concentration again increased through the early morning on the next day. An approximately 25% difference in serum phosphorus concentration at the apex and the nadir was documented. A non-linear relationship between the serum concentrations of phosphorus and ionized calcium over time was identified. Diurnal variations of serum phosphorus concentration and associations between the trending of serum phosphorus and ionized calcium concentrations were evident in a group of clinically healthy adult cats housed in a controlled environment. These findings can help in the interpretation of clinical and research data regarding calcium and phosphorus metabolism and kidney health in cats.

A Meta-Analysis on Quantitative Calcium, Phosphorus and Magnesium Metabolism in Horses and Ponies.

The aims of the present meta-analysis were (i) to re-evaluate the factorially calculated Ca, P and Mg requirements to replace endogenous faecal losses, taking new data into account, (ii) to identify potential differences between horses and ponies regarding requirements, apparent digestibility, serum levels and renal excretion of Ca, P and Mg and (iii) to investigate the influence of mineral sources, i.e., "inorganic" sources from added mineral salts and "organic" sources from feed plants. For P, the water solubility of "inorganic" sources was taken into consideration. Data on the aforementioned parameters from 42 studies were plotted against intake, similar to the Lucas test for true digestibility and faecal endogenous losses. Within specific intake ranges, data were compared using t-tests and an ANOVA, followed by Holm-Sidak post hoc tests. Ponies had lower endogenous faecal Mg losses than horses. Consequently, apparent Mg digestibility was higher in ponies. Factorial calculations of Mg requirements to replace faecal losses showed that ponies needed approximately half of the current recommended amount, while horses required 1.9 times the amount currently recommended by Kienzle and Burger. The overall mean matched previous recommendations. For Ca, there was no discernible difference between ponies and horses. True Ca digestibility calculated by the Lucas test was higher and endogenous losses were lower when "organic" Ca was fed as opposed to when "inorganic" sources were used. The resulting factorial calculations of the requirements to replace faecal losses were close to current recommendations for "organic" Ca. For "inorganic" sources, however, the new calculations were below the recommended level. For P, there were no discernible differences between horses and ponies. There were also no clear effects of "inorganic" or "organic" P sources. The water solubility of "inorganic" sources was the key factor determining P metabolism. Water-soluble P sources exhibited higher true and apparent digestibility. The intake of these P sources led to hyperphosphatemia and hyperphosphaturia, even at low intakes. In other species, this has been shown to pose a health risk. Therefore, it is recommended to avoid the use of highly water-soluble "inorganic" P sources in horses and ponies. Given the lower digestibility of insoluble P sources, the factorially calculated P requirements for such sources are higher than the current recommendations.

Phosphorus Metabolism-Related Genes Serve as Novel Biomarkers for Predicting Prognosis in Bladder Cancer: A Bioinformatics Analysis.

Phosphorus metabolism might be associated with tumor initiation and progression. We aimed to screen out the phosphorus metabolism genes related to bladder cancer and construct a clinical prognosis model. The dataset used for the analysis was obtained from TCGA database. GO and KEGG enrichment analyses were subsequently applied to differentially expressed genes. Consensus clustering was utilized, and different clusters of the tumor immune microenvironment and other features were compared. The phosphorus metabolism-related genes involved in prognosis were screened out by univariate Cox regression, LASSO regression and multivariate Cox regression analysis, and a nomogram was constructed. The performance of the nomogram was validated using TCGA dataset and the GEO dataset, respectively. Overall, 405 phosphorus metabolism-related differentially expressed genes from TCGA database were identified, which were associated with phosphorylation, cell proliferation, leukocyte activation, and signaling pathways. Two clusters were obtained by consistent clustering. After tumor immune microenvironment analysis, significant differences in immune cell infiltration between cluster 1 and cluster 2 were found. Four phosphorus metabolism-related genes (LIME1, LRP8, SPDYA, and MST1R) were associated with the prognosis of bladder cancer (BLCA) patients. We built a prognostic model and visualized the model as a nomogram. Calibration curves demonstrated the performance of this nomogram, in agreement with that shown by the ROC curves. We successfully identified four phosphorus metabolism-related genes associated with prognosis, providing potential targets for biomarkers and therapeutics. A nomogram based on these genes was developed. Nevertheless, this study is based on bioinformatics, and experimental validation remains essential.

Vitamin D and Sarcopenia in the Senior People: A Review of Mechanisms and Comprehensive Prevention and Treatment Strategies.

This article reviews the mechanisms and prevention strategies associated with vitamin D and sarcopenia in older adults. As a geriatric syndrome, sarcopenia is defined by a notable decline in skeletal muscle mass and strength, which increases the risk of adverse health outcomes such as falls and fractures. Vitamin D, an essential fat-soluble vitamin, is pivotal in skeletal muscle health. It affects muscle function through various mechanisms, including regulating calcium and phosphorus metabolism, promoting muscle protein synthesis, and modulation of muscle cell proliferation and differentiation. A deficiency in vitamin D has been identified as a significant risk factor for the development of sarcopenia in older adults. Many studies have demonstrated that low serum vitamin D levels are significantly associated with an increased risk of sarcopenia. While there is inconsistency in the findings, most studies support the importance of vitamin D in maintaining skeletal muscle health. Vitamin D influences the onset and progression of sarcopenia through various pathways, including the promotion of muscle protein synthesis, the regulation of mitochondrial function, and the modulation of immune and inflammatory responses. Regarding the prevention and treatment of sarcopenia, a combination of nutritional, exercise, and pharmacological interventions is recommended. Further research should be conducted to elucidate the molecular mechanism of vitamin D in sarcopenia, to study genes related to sarcopenia, to perform large-scale clinical trials, to investigate special populations, and to examine the combined application of vitamin D with other nutrients or drugs. A comprehensive investigation of the interconnection between vitamin D and sarcopenia will furnish a novel scientific foundation and productive strategies for preventing and treating sarcopenia. This, in turn, will enhance the senior people's quality of life and health.