D3 Treatment Research Articles

Vitamin D3 alleviates intestinal injury in necrotizing enterocolitis and lipopolysaccharide-induced inflammatory response in dendritic cells in rats.

Necrotizing enterocolitis (NEC) is a serious condition that predominantly affects premature infants and involves an aberrant immune response and inflammatory cytokine release resulting in intestinal epithelial damage. The current study investigated the immunoregulatory effects of vitamin D3 on the maturation and activation of dendritic cells (DCs) and the antiinflammatory impact on the intestines in a neonatal rat model of NEC.Materials and methods: Inflammatory damage to intestinal tissue was assessed via morphological changes and apoptosis and DC expression of costimulatory molecules, inflammatory factors, and immunoregulatory factors by immunohistochemical staining, quantitative real-time PCR, and immunofluorescence. The fluorescein isothiocyanate-ovalbumin (FITC-OVA) uptake assay was used to analyze DC endocytosis. Vitamin D3 administration attenuated intestinal damage and apoptosis, inhibiting CD86 and increasing CD80 expression. Lipopolysaccharide (LPS)-challenged DC2.4 cells in vitro showed upregulated CD86, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), inducible nitric oxide synthase (iNOS), and indoleamine 2,3-dioxygenase 1 (IDO-1) expression, which were all reduced by vitamin D3, except for IDO-1. LPS inhibited CD80 expression, which was restored by vitamin D3 treatment, and endocytic capacity was improved. Vitamin D3 ameliorated intestinal damage in neonatal rats with NEC and exerted antiinflammatory and immunomodulatory effects on DCs. Vitamin D3 has potential as a supplementary treatment for NEC patients.

Enhancing production efficiency through optimizing plant density in maize-soybean strip intercropping.

Due to limited arable land resources, intercropping has emerged as an efficient and sustainable production method for increasing total grain yield per unit land area. Maize-soybean strip intercropping (MSSI) technology is being widely promoted and applied across China. However, the combination of optimal density for achieving higher production efficiency of both soybean and maize remains unclear. The objective of this study was to evaluate the differences in yield, economic benefits, land, and nitrogen (N) efficiency in MSSI systems under different densities. Five maize/soybean density combinations (67,500/97,500 plants ha-1, D1; 67,500/120,000 plants ha-1, D2; 67,500/142,500 plants ha-1, D3; 60,000/142,500 plants ha-1, D4; 52,500/142,500 plants ha-1, D5) were set under the same N input in the field experiment. The results demonstrated that optimizing the density in the intercropping system could enhance production efficiency. Increasing the density of soybean and maize significantly increased the total grain yield (D3 > D2 > D1 > D4 > D5). The D3 treatment, exhibiting the best comprehensive performance, also promoted increases in leaf area index, dry matter accumulation, and N absorption and utilization. Path analysis indicated that density had the most substantial impact on maize yield, while grain number had the greatest influence on soybean yield, with contribution rates of 49.7% and 61.0%, respectively. These results provide valuable insights into optimal field density for summer planting in MSSI, facilitating its wider adoption.

The impact of vitamin D3 administration and of high fat diet on oxidative stress and inflammation in experimentally induced polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is commonly associated with obesity and may be exacerbated by the lack of vitamin D3. The study aimed to investigate the effects of vitamin D3 administration in female rats with PCOS and prolonged high fat diet (HFD). Forty-four female Wistar rats, 180-200 g, 10 weeks old, were randomly allocated into 2 groups (n=22) that received a single dose intramuscular injection of: sesame oil (group I), or estradiol valerate (5 mg) in sesame oil (group II). After 4 weeks, intraovarian cysts developed in group II, as evidenced by ultrasonography. In the next step, half of rats from each group received standard diet (SD) and the other half high fat diet, through oral gavage, for 17 weeks, the following groups being obtained: Control (SD), HFD, PCOS (PCOS+SD) and PCOS+HFD. Next, all the rats received, for 5 weeks, 500 UI/kg/day vitamin D3, through oral gavage. Lipid peroxidation was assessed through malondialdehyde level in the ovary and periovarian tissue and the inflammation was quantified in ovary by NFkB, pNFkB, NRF2 and SOD1 expressions. Ovaries from all groups were collected for histopathological analysis. Blood samples were taken to evaluate the basal insulin, triglycerides and total cholesterol levels throughout the experiment. Both groups with PCOS recorded significant increases of malondialdehyde in ovaries (p<0.001) and in periovarian tissue, especially in PCOS+HFD (p<0.05), even after vitamin D3 administration. PCOS+HFD group treated with vitamin D3 showed a high degree of inflammation in ovarian histopathology but with decreased pNFkB expression (p<0.01) while PCOS group recorded an increased SOD1 expression (p<0.05). Additionally, vitamin D3 treatment attenuated the insulin level (p<0.001) in PCOS and in HFD groups and the total cholesterol level in PCOS+HFD group, but triglycerides recordings were without statistical significance (p>0.05). HFD induced inflammation in ovaries, evidenced histologically and through increases of COX2 expressions (p<0.05) without significant influences on oxidative stress and on cholesterol levels. Polycystic ovary syndrome is associated with oxidative stress and inflammation in the ovary tissue and in blood with increased levels of insulin, total cholesterol and triglycerides that might be partially mitigated by vitamin D3 oral administration.

Effects of Vitamin D on tumor cell proliferation and migration, tumor initiation and anti-tumor immune response in head and neck squamous cell carcinomas

BackgroundHead and neck squamous cell carcinomas (HNSCCs) are among the six most common cancers, with a constantly poor prognosis. Vitamin D has been found to have antineoplastic and immunomodulatory properties in various cancers. This study investigated the impact of Vitamin D on the initiation and progression as well as antitumor immune response in HNSCCs, both in vitro and in vivo. MethodsAn immunocompetent, orthotopic oral carcinogenesis mouse model was used to examine the influence of Vitamin D3 substitution on HNSCC initiation and progression in vivo. Tumor immune infiltration was analyzed by immunohistochemistry targeting CD3, CD8, NKR-P1C, FOXP3, and CD163. Two HPV- and two HPV+ HNSCC cell lines were treated with 1,25-dihydroxyvitamin D3 to analyze effects on tumor cell proliferation, migration and transcriptomic changes using RNA-sequencing, differential gene expression and gene set enrichment analysis. ResultsVitamin D3 treatment led to a significant suppression of HNSCC initiation and progression, while also stimulating tumor immune infiltration with CD3+, CD8+ and NKR-P1C+ cells and lowering levels of M2 macrophages and Treg cells in vivo. In vitro experiments showed an inhibition of HNSCC cell proliferation and migration in HPV+ and HPV- cell lines. RNA-sequencing showed significant regulations in IL6 JAK STAT3, hypoxia signaling and immunomodulatory pathways upon Vitamin D3 treatment. ConclusionThe findings of our study highlight the promising potential of Vitamin D in the therapeutic repertoire for HNSCC patients given its immune modulating, anti-proliferative and anti-migratory properties. Clinical transferability of those in vitro and in vivo effects should be further validated in clinical trials.

Impact of fertilizer doses on soil properties, vegetative growth, fruit quality and biochemical compounds of strawberry (Fragaria × ananassa Duch)

Fertilizers are important for plant growth, yield enhancement, and achieving food security, but overdose can have negative effects. This study sought to determine the impact of different fertilizer doses on soil properties, vegetative growth, fruit quality, and biochemical compounds of strawberry (Fragaria × ananassa Duch) cv. ‘Camarosa’. During the years 2022-2023, strawberry seedlings were grown in pots in a greenhouse. Four increasing dosages of fertilizers were applied. The results showed that following treatment, electrical conductivity and soil organic matter rose to maximum values of 176.26 µS. cm-1 and 2.63%, respectively, with d2 treatment. However, the pH was initially high before dropping considerably to 7.34 with d4 dosage. Treatment d1 was highly suggested for enhanced fruit number (5.8) and total yield (729 g. plant-1). The treatment d2 produced the highest fruit weight (24.3 g), volume (27.71 cm3), length (5.55 cm), and width (5.15 cm). The medium dose d3 drastically increased leaf area (2652.76 cm2), total soluble solids (7.4 °Brix), total phenols (1,332.54 mg GAE· L-1) and antioxidant activity (89.53%), but not significantly. The maximum petiole length (12.66 cm), petiole number (29.4), chlorophyll content, runners number (6), roots length (22.33 cm), fresh root and shoot weight (73.11 and 96.41 g), root and shoot dry weight (10.84 and 30.64 g), were recorded at d4 treatment. In control plants, all of these measures were lower, despite having higher fruit pH (3.72), titratable acidity (0.87%), and flowers number (4.40). In conclusion, increasing fertilizer doses may affect soil and strawberry plant qualities, and farmers must use them appropriately.

362 Nutrikinetic evaluation and modeling of 25-hydroxyvitamin D3 in beef cattle

Abstract The objective of this study was to evaluate serum 25-hydroxyvitamin D3 [25(OH)D3] status in beef cattle when 1) fed diets with supplemental 25(OH)D3 or calcidiol (HyD, dsm-firmenich, Plainsboro, NJ), and 2.) a single dose of calcidiol was administered to cannulated heifers on nutrikinetic evaluation and predictive modeling simulations. In experiment 1, crossbred heifer calves [n = 96, initial body weight (BW) = 222 ± 12.4 kg] were assembled from auction markets near Dickson, TN and transported ~1,069 km to Manhattan, KS. Heifers (n = 12 per pen) were stratified by BW and randomly allocated to a corn-based receiving diet with one of four dietary treatments: 1) No supplemental D3 or calcidiol (CON, n = 24), 2) 3,000 IU supplemental D3·heifer⁻¹·d⁻¹ (D3, n = 24), 3.) 0.5 mg calcidiol/h/d (Hy D Low, n = 24), or 4.) 1.0 mg calcidiol·heifer⁻¹·d⁻¹ (Hy D High, n = 24) for 60 d. Blood samples were collected from each heifer prior to transport (d -1), on arrival (d 0) and on d 14, 31, and 60 of dietary treatment period. Data were analyzed using the GLIMMIX procedure of SAS using animal as experimental unit and treatment as fixed effect. HyD High calves had greater (P &amp;lt; 0.001) serum 25(OH)D3 concentrations than HyD Low at d 14 and 31 (Figure 1 and 2). At d 14, 31 and 60, HyD High and HyD Low calves had greater (P &amp;lt; 0.001) serum 25(OH)D3 concentrations than CON or D3 treatments. In experiment 2, cannulated crossbred heifers (n = 8, initial BW = 289 ± 44.9 kg were randomly assigned to one of two treatments: 1.) 3 mg/272 kg BW calcidiol, or 2.) 5 mg/272 kg BW calcidiol in a single dose administered via rumen cannula at h 0. Serial blood samples were collected at baseline out to 70 d post-dose. Serum 25(OH)D3 concentrations were analyzed via HPLC coupled with tandem MS (dsm-firmenich, Belvidere, NJ). Predictive modeling simulations of serum 25(OH)D3 concentrations used non-parametric superposition (Certara Phoenix WinNonlin 64, St. Louis, MO) from applying non-compartmental analysis with the assumptions of linearity, independent calcidiol dose response, and the rate of absorption and the average systemic clearance were consistent for each calcidiol dosing interval. The elimination half-life (t1/2) of calcidiol was determined to be an average of 7.1 d and area under change in concentration-time curve time 0 to the last time point that measured above baseline concentration post dose (AUC0-last) averaged of 32.6 d (Table 1). Non-parametric dosing simulations using nutrikinetic parameters from experiment 2 suggest that administration of two 5 mg oral doses of calcidiol with daily feeding of 1 mg would result in a rapid and sustained increase in serum 25(OH)D3. However, simulations should be confirmed in vivo before implementation.

Optimizing nitrogen fertilization and planting density management enhances lodging resistance and wheat yield by promoting carbohydrate accumulation and single spike development

AbstractNitrogen fertilizer application and increasing planting density have been recognized as essential measures to achieve higher wheat (Triticum aestivum L.) yields. However, inadequate management practices often lead to poor culm quality and lodging. We hypothesized that optimizing culm characteristics could be a feasible approach to improving both lodging resistance and yield. In this study, field experiments involved five nitrogen levels (0, 180, 240, 300, and 360 kg ha−1) and three planting densities (225, 375, and 525 × 104 ha−1). Two wheat cultivars with different lodging resistance were selected and their culm morphological characteristics, biochemical components, field lodging rate, and yield in different treatments were measured. We found that field lodging rate in wheat was negatively correlated with yield, and there was a contradiction between increasing spike number and lodging resistance. Culm carbohydrate accumulation affected field lodging rate by regulating culm quality rather than the center of gravity height. Compared with Xinmai 26, Xinhuamai 818 had higher culm carbohydrate accumulation, which increased the breaking strength and yield by 14.2% and 17.0%. Nitrogen application and planting density had significant effects on yield and lodging resistance. Compared with N0 treatment, increasing nitrogen application rate improved yield of 67.2%–83.2% by increasing spike number and grain number per spike, and the N2 treatment showed the largest increase. Planting density had little effect on yield. Reducing planting density can increase the culm carbohydrate accumulation and enhance lodging resistance. Compared with D3 treatment, the culm breaking strength was increased by 27.6% under the D1 treatment. This study determined that the optimal combination of nitrogen and density for improving wheat lodging resistance and yield is 240 kg ha−1 and 225 × 104 ha−1. This combination enhances culm breaking strength by increasing carbohydrate accumulation and achieves high yield by increasing grain number per spike, 1000‐grain weight, and stabilizing spike number.

The effects of in vitro vitamin D treatment on glycolytic reprogramming of bone marrow-derived dendritic cells from Ldlr knock-out mouse

Dendritic cells (DCs) undergo glycolytic reprogramming, a metabolic conversion process essential for their activation. Vitamin D has been reported to affect the function of DCs, but studies in metabolic diseases are insufficient. This study investigates the effects of in vitro 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) treatment on glycolytic reprogramming of bone marrow-derived dendritic cells (BMDCs) from control, obese, and atherosclerosis mice. Six-week-old male C57BL/6J mice were fed a control diet (CON) or a Western diet (WD), and B6.129S7-Ldlrtm1Her/J mice were fed a Western diet (LDLR−/−) for 16 weeks. BMDCs were cultured in a medium containing 1,25(OH)2D3 (10 nM) for 7 days and stimulated with lipopolysaccharide (LPS, 50 ng/mL) for 24 h. In mature BMDCs, 1,25(OH)2D3 treatment decreased basal and compensatory glycolytic proton efflux rates (glycoPER), the expression of surface markers related to immune function of DCs (MHC class II, CD80, and CD86), and IL-12p70 production. In addition, mTORC1 activation and nitric oxide (NO) production were suppressed by 1,25(OH)2D3 treatment in mature BMDCs. The effect of 1,25(OH)2D3 treatment on IL-12p70 production and mTORC1 activity in the LDLR−/− group was greater than in the CON group. These findings suggest that vitamin D can affect the metabolic environment of BMDCs by regulating glycolytic reprogramming as well as by inducing tolerogenic phenotypes of DCs.

Vitamin D3 suppresses Npt2c abundance and differentially modulates phosphate and calcium homeostasis in Npt2a knockout mice

Vitamin D3 is clinically used for the treatment of vitamin D3 deficiency or osteoporosis, partially because of its role in regulating phosphate (Pi) and calcium (Ca2+) homeostasis. The renal sodium-phosphate cotransporter 2a (Npt2a) plays an important role in Pi homeostasis; however, the role of vitamin D3 in hypophosphatemia has never been investigated. We administered vehicle or vitamin D3 to wild-type (WT) mice or hypophosphatemic Npt2a−/− mice. In contrast to WT mice, vitamin D3 treatment increased plasma Pi levels in Npt2a−/− mice, despite similar levels of reduced parathyroid hormone and increased fibroblast growth factor 23. Plasma Ca2+ was increased ~ twofold in both genotypes. Whereas WT mice were able to increase urinary Pi and Ca2+/creatinine ratios, in Npt2a−/− mice, Pi/creatinine was unchanged and Ca2+/creatinine drastically decreased, coinciding with the highest kidney Ca2+ content, highest plasma creatinine, and greatest amount of nephrocalcinosis. In Npt2a−/− mice, vitamin D3 treatment completely diminished Npt2c abundance, so that mice resembled Npt2a/c double knockout mice. Abundance of intestinal Npt2b and claudin-3 (tight junctions protein) were reduced in Npt2a−/− only, the latter might facilitate the increase in plasma Pi in Npt2a−/− mice. Npt2a might function as regulator between renal Ca2+ excretion and reabsorption in response to vitamin D3.

Optimal Planting Density Increases the Seed Yield by Improving Biomass Accumulation and Regulating the Canopy Structure in Rapeseed.

Planting density is an important factor affecting plant growth and yield formation in rapeseed. However, the understanding of the mechanism underlying the impact of planting density on biomass, canopy, and ultimate seed yield remains limited. A field experiment was conducted to investigate the effect of planting density on seed yield, yield components, biomass accumulation and partitioning, and canopy structure. Five planting density levels were set as D1 (2.4 × 105 plants ha-1), D2 (3.6 × 105 plants ha-1), D3 (5.4 × 105 plants ha-1), D4 (6.0 × 105 plants ha-1), and D5 (7.2 × 105 plants ha-1). The results showed that with planting density increasing from D1 to D3, the seed yield, number of pods in population, and 1000-seed weight increased, while seedling survival rate, yield per plant, number of pods per plant, and number of seeds per plant decreased. When planting density increased to D4 and D5, seed yield dramatically decreased due to a decreased number of seeds per pod and 1000-seed weight. Increasing planting density from D1 to D3 increased biomass accumulation in all organs. D3 produced the highest biomass partitioning in seeds. In addition, D2 and D3 treatments had a high level of pod area index (5.3-5.8), which caused an approximately 93% of the light to be intercepted. The distribution of light in D2 and D3 was more evenly spread, with the upper and lower parts of the canopy displaying a distribution ratio of roughly 7:3. Therefore, D2 and D3 produced the highest seed yields. In conclusion, D2 and D3 are recommended in rapeseed production due to their role in improving biomass accumulation and partitioning and canopy structure.

Vitamin D is involved in the regulation of Cl− uptake in zebrafish (Danio rerio)

Cl− is a major anion in the bodily fluids of vertebrates, and maintaining its homeostasis is essential for normal physiological functions. Fishes inhabiting freshwater (FW) passively lose body fluid ions, including Cl−, to the external environment because of the electrochemical gradient of ions across the body surface. Therefore, FW fishes have to actively absorb Cl− from the surroundings to maintain ion homeostasis in their bodily fluids. Hormonal control is vital for modulating ion uptake in fish. Vitamin D is involved in the regulation of Ca2+ uptake and acid secretion in fish. In the present study, we found that the levels of bioactive vitamin D, 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3), significantly increased in zebrafish embryos and adults after exposure to water containing low levels of Cl−. Moreover, the administration of 1α,25(OH)2D3 treatment (20 μg/L) in zebrafish embryos, and intraperitoneal (i.p.) injection of 1α,25(OH)2D3 (5 μg/kg body mass) in zebrafish adults, resulting the increased Cl− content in bodily fluid in zebrafish. Na+-Cl− cotransporter 2b (NCC2b) and Cl− channel 2c (CLC2c) are specifically expressed during Cl− uptake by ionocytes in zebrafish. Our results indicated that the mRNA and protein expression of NCC2b and CLC2c considerably increased in the zebrafish with exogenous 1α,25(OH)2D3 treatment. Additionally, exogenous 1α,25(OH)2D3 administration increased the number of NCC2b- and CLC2c-expressing cells in yolk skins of zebrafish embryos and the gill filaments of zebrafish adults. Transcript signals of vitamin D receptors (VDRs) were identified in NCC2b-expressing cells. Knockdown of VDRa and VDRb significantly reduced the expression of NCC2b and CLC2c and the number of NCC2b- and CLC2c-expressing cells. These results indicate that vitamin D can affect Cl− uptake in zebrafish and extend our knowledge of the role of vitamin D in fish physiology.

1,25-Dihydroxyvitamin D3 Suppresses Prognostic Survival Biomarkers Associated with Cell Cycle and Actin Organization in a Non-Malignant African American Prostate Cell Line.

Vitamin D3 is a steroid hormone that confers anti-tumorigenic properties in prostate cells. Serum vitamin D3 deficiency has been associated with advanced prostate cancer (PCa), particularly affecting African American (AA) men. Therefore, elucidating the pleiotropic effects of vitamin D on signaling pathways, essential to maintaining non-malignancy, may provide additional drug targets to mitigate disparate outcomes for men with PCa, especially AA men. We conducted RNA sequencing on an AA non-malignant prostate cell line, RC-77N/E, comparing untreated cells to those treated with 10 nM of vitamin D3 metabolite, 1α,25(OH)2D3, at 24 h. Differential gene expression analysis revealed 1601 significant genes affected by 1α,25(OH)2D3 treatment. Pathway enrichment analysis predicted 1α,25(OH)2D3- mediated repression of prostate cancer, cell proliferation, actin cytoskeletal, and actin-related signaling pathways (p < 0.05). Prioritizing genes with vitamin D response elements and associating expression levels with overall survival (OS) in The Cancer Genome Atlas Prostate Adenocarcinoma (TCGA PRAD) cohort, we identified ANLN (Anillin) and ECT2 (Epithelial Cell Transforming 2) as potential prognostic PCa biomarkers. Both genes were strongly correlated and significantly downregulated by 1α,25(OH)2D3 treatment, where low expression was statistically associated with better overall survival outcomes in the TCGA PRAD public cohort. Increased ANLN and ECT2 mRNA gene expression was significantly associated with PCa, and Gleason scores using both the TCGA cohort (p < 0.05) and an AA non-malignant/tumor-matched cohort. Our findings suggest 1α,25(OH)2D3 regulation of these biomarkers may be significant for PCa prevention. In addition, 1α,25(OH)2D3 could be used as an adjuvant treatment targeting actin cytoskeleton signaling and actin cytoskeleton-related signaling pathways, particularly among AA men.

Effect of 1, 25 dihydroxy v itamin D3 on T Helper 17 (TH17) cell pathways in diarrhea associated irritable bowel syndrome

Purpose: To investigate the effect of 1, 25-dihydroxyvitamin D3 (1,25-(OH)2D3) on T-Helper 17 (TH17) cell pathways in diarrhea-associated irritable bowel syndrome (IBS-D). Methods: 120 children with IBS-D were treated with Smecta alone and Smecta in addition to 1,25-(OH)2D3 in Hangzhou Ninth Peoples Hospital, Hangzhou, China. Blood samples were taken to determine the levels of 1,25-(OH)2D3, IL-17, IFN-γ, IL-23, and IL-6, as well as Th17 cell ratio. Furthermore, IL-17 and RORγt expressions were evaluated. Results: Serum 1,25-(OH)2D3 levels decreased in IBS-D patients and were negatively correlated with IL-17 levels in serum and Th17 cells in peripheral blood. Treatment with 1,25-(OH)2D3 significantly reduced serum IFN-γ, IL-17, IL-23 and IL-6 levels in IBS-D patients (p &lt; 0.05). Percentage of Th17 cells, and IL-17 and RORγt expression levels were significantly reduced in IBS-D patients after 1,25-(OH)2D3 treatment (p &lt; 0.05). Conclusion: This study shows that 1,25-(OH)2D3 reduces serum IFN-γ, IL-17, IL-23, IL-6 levels, Th17 cells and RORγt expression in IBS-D patients. Additional studies with larger sample sizes are required to validate these findings.

The MraY Inhibitor Muraymycin D2 and Its Derivatives Induce Enlarged Cells in Obligate Intracellular Chlamydia and Wolbachia and Break the Persistence Phenotype in Chlamydia.

Chlamydial infections and diseases caused by filarial nematodes are global health concerns. However, treatment presents challenges due to treatment failures potentially caused by persisting Chlamydia and long regimens against filarial infections accompanied by low compliance. A new treatment strategy could be the targeting of the reduced peptidoglycan structures involved in cell division in the obligate intracellular bacteria Chlamydia and Wolbachia, the latter being obligate endosymbionts supporting filarial development, growth, and survival. Here, cell culture experiments with C. trachomatis and Wolbachia showed that the nucleoside antibiotics muraymycin and carbacaprazamycin interfere with bacterial cell division and induce enlarged, aberrant cells resembling the penicillin-induced persistence phenotype in Chlamydia. Enzymatic inhibition experiments with purified C. pneumoniae MraY revealed that muraymycin derivatives abolish the synthesis of the peptidoglycan precursor lipid I. Comparative in silico analyses of chlamydial and wolbachial MraY with the corresponding well-characterized enzyme in Aquifex aeolicus revealed a high degree of conservation, providing evidence for a similar mode of inhibition. Muraymycin D2 treatment eradicated persisting non-dividing C. trachomatis cells from an established penicillin-induced persistent infection. This finding indicates that nucleoside antibiotics may have additional properties that can break bacterial persistence.

Vitamin D Attenuates Fibrotic Properties of Fibrous Dysplasia-Derived Cells for the Transit towards Osteocytic Phenotype.

Fibrous dysplasia (FD) poses a therapeutic challenge due to the dysregulated extracellular matrix (ECM) accumulation within affected bone tissues. In this study, we investigate the therapeutic potential of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in managing FD by examining its effects on FD-derived cells in vitro. Our findings demonstrate that 1,25(OH)2D3 treatment attenuates the pro-fibrotic phenotype of FD-derived cells by suppressing the expression of key pro-fibrotic markers and inhibiting cell proliferation and migration. Moreover, 1,25(OH)2D3 enhances mineralization by attenuating pre-osteoblastic cellular hyperactivity and promoting maturation towards an osteocytic phenotype. These results offer valuable insights into potential treatments for FD, highlighting the role of 1,25(OH)2D3 in modulating the pathological properties of FD-derived cells.

Response signatures of intestinal microbiota and gene transcription of the pearl gentian grouper to Vibrio harveyi infection

Vibrio harveyi causes high mortality and severely limits grouper culture. The gut microbiota is an important biological barrier against pathogen invasion. In this study, we investigated dynamic changes in the intestinal microbial community, gene transcription and immune responses signatures of pearl gentian grouper (Epinephelus fuscoguttatus♂ × Epinephelus lanceolatus♀) at 0, 3 and 7 days (referred to as d0, d3 and d7 groups, respectively) after infection with V. harveyi. The results demonstrated that the d7 treatment reduced the gut microbial diversity and increased the proportion of Proteobacteria and Cyanobacteria. Notably, several putative pathogenic genera (Sphingomonas and Bacteroides) proliferated, while putative probiotic genera (Rhodococcus and Lactobacillus) reduced, and these changes in intestinal bacteria might be correlated to the alterations of host immune-related molecules. The d3 and d7 treatments also altered the histomorphology and gene transcription profiles mainly associated with immune function in intestine, such as ‘MAPK signaling pathway’, ‘Apoptosis’ and ‘Toll-like receptor (TLR) signaling pathway’. Furthermore, d3 group induced a homeostatic dysregulation of the antioxidant system, cytokines and TLR signaling, with a tendency to gradually return to a normal state in d7 group, along with the apoptosis process. The pathogenic infection suppressed the expression of JNK pathway and enhanced the ERK pathway. In conclusion, the dysbiosis of the intestinal bacterial communities caused by the immune changes that occurred during V. harveyi infection disrupted the intestine health in the pearl gentian grouper. These results provided a comprehensive understandings of the immune defense mechanisms in fish and valuable references to develop disease control strategies in grouper aquaculture.

Evaluating the Impact of Vitamin D3 on NF-κB and JAK/STAT Signaling Pathways in Drosophila melanogaster.

This study delved into the consequences of prolonged administration of vitamin D3 on innate immune systems, particularly NF-κB and JAK/STAT, in Drosophila melanogaster. The outcomes indicated that vitamin D3 treatment exhibited a notable capacity to improve the survival of adult flies with compromised immune functions, a condition induced by the loss of PGRP-LB, particularly when the flies were exposed to heat-killed Escherichia coli. The PGRP-LBΔ mutant line that was treated with heat-killed E. coli experienced reduced survival. Treatment of heat-killed E. coli-treated PGRP-LBΔ with vitamin D3 resulted in improved survival, and this phenotypic feature might be due to the downregulation of gene expression in the NF-κB and JAK/STAT pathways. However, a higher concentration of vitamin D3 was associated with decreased survival, potentially linked to intricate immunological responses. The research also underscored the influence of vitamin D3 on the expression of antioxidant genes, sod1 and sod2, indicating an augmented resistance to oxidative stress. Further, this study revealed the effect of vitamin D3 on the reproductive status of the autoinflammatory model, showing an increase in pupae and adult flies with a treatment of 10 mM vitamin D3, suggesting the potential benefits of vitamin D3 on the reproductive profile. Overall, this study provides preliminary insights into the complex interactions between vitamin D3, immune pathways, oxidative responses in the cell, and reproduction in Drosophila.

Dietary Super-Doses of Cholecalciferol Fed to Aged Laying Hens Illustrates Limitation of 24,25-Dihydroxycholecalciferol Conversion

BackgroundOlder humans taking high concentrations of vitamin D3 supplementation for a prolonged time may be at risk of vitamin D toxicity. It is unclear how dietary super-doses (10,000 times greater than the requirement) can affect vitamin D3 status in aged animals. Aged laying hens could be a model to compare vitamin D3 supplementation effects with women in peri- or postmenopausal stages of life. ObjectivesWe investigated the dietary super-dose impacts of cholecalciferol (vitamin D3) on vitamin D3 status in aged laying hens in production. MethodsForty-eight 68-wk-old Hy-Line Brown laying hens were individually housed in cages with 8 hens per dietary treatment for 11 wk. Hens were randomly assigned to 1 of 6 treatment groups of dietary vitamin D3 supplementation and consumed ad libitum. Supplementation concentrations were 400, 800, 7400, 14,000, 20,000, and 36,000 IU D3/kg of feed. At the end of the study, all hens were sacrificed, and tissue samples and feces were collected. Plasma and egg yolk vitamin D3 metabolites, calcium and phosphorus composition of eggshells, ileal digesta, and feces were measured. Duodenal, ileal, liver, and kidney gene expression levels were also measured. ResultsWe observed that increasing dietary vitamin D3 increased plasma vitamin D3 and egg yolk vitamin D3 (P < 0.0001 for both sites). We also observed an increase in plasma 24,25-dihydroxycholecalciferol as dietary vitamin D3 concentrations increased (P < 0.0001). The plasma 25-hydroxycholecalciferol:24,25-dihydroxycholecalciferol ratio exhibited an asymptotic relationship starting at the 14,000 IU/kg D3 treatment. ConclusionsDietary super-doses of vitamin D3 led to greater plasma and egg yolk vitamin D3 concentrations, which shows that aged laying hens can deposit excess vitamin D3 in egg yolk. We suggest future research should explore how 24-hydroxylation mechanisms are affected by vitamin D3 supplementation. Further understanding of 24-hydroxylation can help ascertain ways to reduce the risk of vitamin D toxicity.

Abstract 766: Effects of supplemental calcium and vitamin D on circulating biomarkers of gut barrier function in colorectal adenoma patients: A randomized controlled trial

Abstract Introduction: Recent experimental evidence shows that intestinal barrier disruption initiates colon inflammation, which may promote colorectal carcinogenesis. In experimental models, vitamin D and calcium improved gut barrier function; however, this has not been assessed in humans. Method: To test the effects of supplemental calcium and vitamin D3 on circulating biomarkers of intestinal mucosal damage (intestinal fatty-acid binding protein, IFABP) and exposure to bacterial products due to impaired gut barrier (lipopolysaccharide-binding protein, LBP), we conducted an “adjunct biomarker study” to a larger 11-center, randomized, placebo-controlled, partial 2 × 2 factorial chemoprevention clinical trial, the Vitamin D/Calcium Polyp Prevention Study. Participants were randomized into four different treatment groups: placebo, 1,200 mg/day calcium, 1,000 IU/day vitamin D3, and 1,200 mg/day calcium plus 1,000 IU/day vitamin D3. Circulating concentrations of LBP and IFABP were measured at baseline and 1-year follow-up using the Meso Scale Discovery electrochemiluminescence assays in a subset of 118 participants included in the adjunct biomarker study. Result: Following one year of vitamin D3 treatment, in the vitamin D3 plus calcium and vitamin D3 groups versus placebo and calcium groups, LBP decreased 10% (316 ng/ml; P=0.23) and IFABP 18% (77 ng/ml; P=0.06). A similar decrease of 20% (P=0.10) was observed for IFABP, but not LBP, in the vitamin D3 plus calcium versus the calcium group. There were no appreciable biomarker changes with calcium treatment. In stratified analyses, we found possible effect modifications by baseline serum 25-OH-vitamin D, total calcium intake, body mass index, and interleukin 6 (IL-6) concentration on estimated vitamin D3 treatment effects on LBP and/or IFABP. Conclusion: These preliminary results are consistent with vitamin D’s potential protective effects on intestinal mucosal barrier and support further research of vitamin D against gut barrier disruption and colorectal neoplasms. Citation Format: Sangji Lee, Veronika Fedirko, Roberd M. Bostick, Bradley Pearce, Elizabeth L. Barry, Robin E. Rutherford, March E. Seabrook. Effects of supplemental calcium and vitamin D on circulating biomarkers of gut barrier function in colorectal adenoma patients: A randomized controlled trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 766.

1,25(OH)2D3 supplementation alleviates gut–vascular barrier disruption via inhibition of S100B/ADAM10 pathway

ABSTRACT Gut–vascular barrier (GVB) is the second barrier in mucosa to control systemic dissemination of gut bacteria. Severe burns induce enteroglial cells to produce S100B and endothelial cells to generate ADAM10 and cause vitamin D3 insufficiency/deficiency and GVB disruption. It is not clear whether vitamin D3 supplementation attenuates GVB damage via regulation of S100B/ADAM10 pathway. Here, GVB disruption was induced by 30% of total body surface area scalds. Rats were treated with 1,25(OH)2D3 (0.05, 0.5 or 5 μg/kg) or S100B monoclonal antibody (S100BmAb, 10 μg/kg) or GI254023X (ADAM10 inhibitor, 100 mg/kg). Rat enteric glial cell-line CRL2690 and rat intestinal microvascular endothelial cells (RIMECs) were treated with S100B (5 μM) or plus 1,25(OH)2D3 (0.05, 0.5 or 5 μM) or GI254023X (5 μM). S100B, TNF-α, 25(OH)D3 and 1,25(OH)2D3 in serum and gut mucosa were determined by enzyme-linked immunosorbent assay. The endothelial permeability was measured using FITC-dextran 70 kDa. ADAM10 and β-catenin expression was assayed by Western blot. The results showed that 1,25(OH)2D3 and 25(OH)D3 concentration in serum reduced whereas TNF-α and S100B in serum and gut mucosa increased in burned rats. S100BmAb, GI254023X and 1,25(OH)2D3 treatment lowered burns-increased GVB permeability. 1,25(OH)2D3 also decreased S100B concentration in serum and gut mucosa. 1,25(OH)2D3 inhibited S100B release from TNF-α-treated CRL2690 and raised β-catenin while decreasing ADAM10 protein in S100B-treated RIMECs. 1,25(OH)2D3 and GI254023X also decreased the endothelial permeability of S100B-treated RIMECs. Collectively, these findings provide evidence that severe burns lower serum 25(OH)D3 and 1,25(OH)2D3 concentration. 1,25(OH)2D3 supplementation alleviates burns-elicited GVB disruption via inhibition of S100B/ADAM10 signaling.