Plasma Zinc Research Articles

P0440 Faecal and plasma zinc as predictors of relapse in quiescent Crohn’s Disease in the Stratifying Crohn’s Using Biomarker Assessment (SCUBA) study

Abstract Background Zinc is an essential trace element playing an important role in immune function, inflammation regulation and intestinal barrier integrity. Deficiency is common in Inflammatory Bowel Disease (IBD). Recent data has shown zinc deficiency is associated with adverse disease specific outcomes in IBD1 and work from our unit has also suggested it a potential predictor of disease course in Crohn’s disease (CD)2. The Stratifying Crohn’s Using Biomarker Assessment (SCUBA) study assessed a number of biomarkers ability to predict relapse in quiescent CD including plasma and faecal zinc. Here we report the performance of these two potential biomarkers. Methods Patients with clinically quiescent CD (Harvey Bradshaw Index ≤3) were recruited prospectively from a single centre over a 2-year period. Faecal calprotectin, quantitative faecal immunochemical test, plasma and faecal zinc were obtained at baseline in addition to routine biochemical work up. Patients over 50 years old were excluded due to overlay with bowel cancer screening programmes as were those with isolated upper gastrointestinal or perianal CD. Patients were followed up for 1 year or until relapse defined by need for escalation of CD related treatment, steroid, surgery or hospitalisation for CD. Results 274 patients were recruited with 216 plasma zinc and 184 faecal zinc samples returned (of which 171 were paired). Median age was 34 years (range 18-49) and123/229 53.7% were female. Median HBI at submission was 1 with median FCP 55µg/g stool and C reactive protein 3mg/l. Median plasma zinc was 11.6 (IQR 10.5-12.6) µmol/L with 54/216 (25.0%) patients deficient at baseline (gender adjusted). Median faecal zinc was 832 (IQR 419-1481) µmol/kg wet weight. 44/229 (19.2%) experienced a relapse during follow up. No association between plasma zinc and faecal zinc was observed (r=0.068, p=0.38). Plasma zinc did not show ability to predict relapse at one year, area under the receiver operating characteristic curve 0.53. Following adjustment for gender, below reference range plasma zinc did not show discriminative value in predicting time to relapse, relative risk (RR) 1.37 (95% CI 0.73-2.56), p=0.33. After adjustment for confounders a RR 0.49 (95% CI 0.21-1.20), p= 0.12 was observed for (log transformed) faecal zinc. Conclusion Previous retrospective studies have reported an association between plasma zinc and time to relapse however this was not observed in our prospective study. Given these finding plasma zinc is unlikely to be of clinical utility with more accurate established biomarkers available. Levels of faecal zinc were noted to be markedly elevated compared to the literature however given the potential for methodological differences further work is required to validate this finding.

P0449 qFIT as a predictor of relapse in quiescent Crohn’s disease – initial results from the Stratifying Crohn’s Using Biomarker Assessment (SCUBA) study

Abstract Background The Stratifying Crohn’s Using Biomarker Assessment (SCUBA) study assessed a number of biomarkers (Faecal Calprotectin (FCP), quantitative faecal immunochemical testing (qFIT), C reactive protein (CRP), plasma and faecal zinc) in their ability to predict relapse in quiescent Crohn’s disease (CD). FCP is widely utilised as a surrogate marker in the monitoring of CD but is labour intensive and expensive. Population qFIT testing is established in colorectal cancer screening and is relatively cheap and simple to analyse. qFIT has been shown to predict relapse in ulcerative colitis1. Here we present a comparison of qFIT and FCP at predicting relapse in quiescent luminal CD. Methods A single centre prospective cohort study was performed. Patients with clinically quiescent CD (Harvey Bradshaw Index ≤3) were identified and provided paired, baseline FCP, qFIT and routine biochemical workup. Patients over 50 years were excluded due to overlay with bowel cancer screening programmes as were those with isolated upper GI or perianal disease. Patients were followed up over 1 year or until relapse defined by need for escalation of CD related treatment, steroids, surgery or hospitalisation for CD. Results 274 patients were recruited with 211 returning paired baseline faecal samples. Median age was 34 years (range 18-49) and 108/211 (51.1%) were female. Median HBI at submission was 1 and median FCP, qFIT and CRP was 61µg/g stool, 9 µg Hb/g and 2 mg/l respectively. 42/211 (19.9%) experienced a relapse during follow up. Both FCP and qFIT showed good ability to predict relapse at 1 year, performing comparably, with the area under the receiver operating characteristic curves (AUROC) 0.80 (95% CI 0.74- 0.85) vs 0.75 (95% CI 0.68-0.80)(p=0.28). Combination biomarker use did not significantly improve performance, AUROC 0.82 (95%CI 0.76- 0.87) p=0.34 and p=0.07 respectively. Optimal threshold for prediction of relapse was >180 µg/g stool for FCP (sensitivity 0.69 and specificity 0.85) and >9 µg Hb/g for qFIT (sensitivity 0.65 and specificity 0.82). Utilising these thresholds (figure 1) patients with both FCP and qFIT above threshold had a probability of relapse free survival of 16.7% (95% CI 0.20%-31.6%) at 1 year vs 95.4% (95% CI 91.7%-99.0%, p<.0001) in patients under threshold. In combination, FCP and qFIT had a positive predictive value of 50.1% and negative predictive value (NPV) of 97.6%. Conclusion qFIT performs well and comparably to FCP in predicting relapse in clinically quiescent luminal CD and may be used in preference to FCP being an easier and cheaper test to undertake. When combined at optimal thresholds, qFIT & FCP show significant discriminatory ability in prediction of CD relapse-free survival with an excellent NPV.

Properties of the major Zn2+-binding site of human alpha-fetoprotein, a potential foetal plasma zinc carrier.

The foetal plasma protein α-fetoprotein (AFP) harbours a high-affinity zinc binding site that is likely involved in transport and delivery of essential zinc during foetal development. Based on a recent electron microscopy structure of AFP and aided by biophysical studies on an AFP-derived peptide, we present a refined 5-coordinate model for this site.

Serum Zinc Levels in Celiac Paediatric Patients on Gluten Free Diet

Celiac disease is an autoimmune disorder with both genetic and environmental factors involved in its pathogenesis. It characterizes by small intestinal atrophy and malabsorption of essential nutrients, vitamins and trace elements due to ingestion of gluten. Zinc is an essential trace element for maintaining integrity of intestinal mucosa, immunity, and growth in children. Therefore, the aim of this study is to evaluate serum zinc levels in celiac paediatric patients on Gluten Free Diet (GFD) and compares it with healthy children. Sera of 22 celiac paediatric patients on GFD and 16 healthy children as a control group were obtained. The samples were prepared and zinc level was estimated via atomic emission spectrophotometer. Ninety one percent of celiac children on GFD had low zinc. The median plasma zinc concentration was significantly lower in celiac children on GFD (0.20 μg/ml) versus controls (0.86 μg/ml) with p value of < 0.0001. The current study shows that serum zinc concentrations are decreased significantly in celiac paediatric patients on GFD, suggesting zinc deficiency. Thus, good dietary guidance, zinc supplement therapy, and regular monitoring of zinc levels are highly recommended for celiac children on GFD.

Effects of Zinc-Biofortified Wheat Intake on Plasma Markers of Fatty Acid Metabolism and Oxidative Stress Among Adolescents.

Zinc deficiency is common worldwide and has been linked to reduced growth and immune function, increased risk of and slower recovery from infections, and increased risk of non-communicable diseases. To address the issue, zinc biofortification of wheat has been proposed as a sustainable approach to increase dietary zinc intake in countries like Pakistan, where zinc deficiency rates are high and wheat is the primary staple crop. Since plasma zinc concentration (PZC) does not reliably respond to small changes in zinc intake, biomarkers sensitive to small changes in zinc intake achievable though biofortification are needed. Activity indices for zinc-dependent metabolic steps of desaturation and elongation of omega-6 fatty acids (FAs) have been proposed as sensitive zinc biomarkers. Oxylipin metabolites of polyunsaturated FAs may also respond to changes in zinc intake and further mediate metabolic response to oxidative stress. The objective of the current study was to assess the effects of consuming zinc-biofortified wheat flour on plasma markers of fatty acid (FA) metabolism in females aged 10-16 years. A nested secondary analysis was conducted in samples from a double-blind, cluster-randomized controlled trial conducted in rural Pakistan, whereparticipants (n = 517) consumed either zinc-biofortified wheat flour or control flour for 25 weeks. Total plasma FAs and oxylipins were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). Activity indices were estimated from the ratios of product to precursor FAs. Except for docosahexaenoic acid (DHA, p < 0.05), no significant intervention effect was observed on plasma FAs and FA activity index endpoints. Zinc-biofortified wheat intake reduced pro-inflammatory oxylipins and biomarkers of oxidative stress, 5-HETE (p < 0.05), 9-HETE (p < 0.05), 11-HETE (p < 0.05), and 15-HETE (p < 0.05), compared with the control. However, after adjustment for multiple comparisons, none of the intervention effects remained significant. Further study of the responsiveness and specificity of plasma oxylipins to changes in zinc intake is warranted.

Zinc Homeostasis Plays Important Roles in Hypoxia Tolerance: A Study Conducted Clinically and In Vitro.

Guo, Yan, Chao Yu, Zhongsheng Lu, Menglan Zhang, Qiang Zhang, and Xiao Liu. Zinc homeostasis plays important roles in hypoxia tolerance: A study conducted clinically and in vitro. High Alt Med Biol. 00:00-00, 2024. Objective: High-altitude environments pose significant challenges to human physiology due to reduced oxygen availability, often resulting in altitude-related illnesses such as high-altitude cerebral edema (HACE). This study focuses on understanding the role of zinc homeostasis in enhancing hypoxia tolerance, which may be pivotal in mitigating the adverse effects of such illnesses. Methods: The study involved healthy individuals from high-altitude (4,500-5,000 m) and low-altitude areas (0-200 m), as well as patients with HACE. Blood samples were collected and analyzed. Additionally, a hypoxic model was developed using human brain microvascular endothelial cells (HBMECs), and zinc intervention was implemented. Results: In the blood samples of patients with HACE and those of healthy individuals, there were over 4,000 differentially expressed genes (DEGs), with more than 300 of them linked to zinc. Among these zinc-associated genes, only carbonic anhydrase I (CA1) exhibited a substantial upregulation in expression, while the expression of others was notably downregulated. Compared with the high-altitude group, hemoglobin (Hb) (14.7 vs. 19.5 g/dl) and plasma zinc (37.0 vs. 94.0 mmol/dl) were lower in HACE, while CA1 (55.4 vs. 8.6 g/l) was elevated (p < 0.01). In vitro studies confirmed that exposure to hypoxia (O2 8%-8.5%, 24 hours) inhibited HBMECs proliferation and migration, increased apoptosis and necrosis, and led to abnormal expression of CA1 and various zinc transport proteins. However, zinc intervention (6 μM, 24 hours) significantly mitigated these adverse effects and improved the cell's ability to tolerate hypoxia. Conclusion: Zinc homeostasis was crucial for hypoxia tolerance. Proper zinc supplementation could potentially alleviate symptoms associated with hypoxia intolerance, such as altitude sickness, but further confirmation was needed.

Taste preference and conditioned taste aversion of the metallothionein-1/2 null mice

To investigate the effects of metallothionein (MT)-1/2 gene knockout on the taste preference and the conditioned taste aversion (CTA), we performed an experiment comparing the behavior of wild type (WT) mice and MT-1/2 null (KO) mice. The taste preference ratio of saccharin solutions (0.1 or 0.2 %) was significantly greater in KO mice than WT mice. The preference ratio of salt and bitter solutions was not different between KO mice and WT mice. After feeding with a low zinc diet, the average saccharin preference ratio was not significantly different between WT and KO mice at any concentration of saccharin. Concentrations of zinc in plasma in KO mice was slightly higher than WT mice, but both were within the physiological range. When conditioning for saccharin using intraperitoneal injection of LiCl, a marked CTA was produced in both WT and KO mice. These results suggest that MT may be involved in the regulation of sweet taste preferences and indicate that the brain function that mediates sweet taste-induced CTA acquisition is maintained in KO mice. In addition, it was suggested that MT was not actively involved in the regulation of plasma zinc concentration in either mice fed a normal diet or mice fed a low zinc diet for a week. The relation between the malfunction of MT-1/2 and signal transduction of intracellular zinc remained to be determined.

Association of Plasma Zinc Status with Severity of Lesions in Patients with Acne Vulgaris: A Cross-Sectional Study

Background: Zinc (Zn) is an essential trace mineral that plays a critical role in maintaining overall skin health and functionality. Zn deficiency has been linked to various dermatological conditions, including acne, eczema, and delayed wound healing, highlighting the mineral’s indispensable role in promoting skin resilience and health. Some investigators have refuted these findings. Objective: was to determine plasma Zn level and Zn status in patients with Acne vulgaris (AV) belonging to Nowshera, Khyber Pakhtunkhwa (KPK) and to find any possible relationship between Zn status &amp; severity of the acne lesions. Methods: Hundred patients of either sex with untreated AV were randomly selected in a cross-sectional study. Based on the Global Acne Grading System (GAGS) the acne lesions were categorized as mild, moderate &amp; severe. Blood samples were taken for determination of serum Zn. The relationship of Zn status with severity of lesions was determined with Pearson Correlations coefficient (r). Results: The study included 42 males and 58 females with male to female ratio of 1:1.4. Mean age was 21.8 years. The average plasma zinc level across the cohort was 67.4 ± 12.6 µg/dL, with males showing slightly higher zinc levels (69.1 ± 11.8 µg/dL) than females (65.8 ± 13.2 µg/dL), though this difference was not statistically significant (p = 0.092). 22% had mild acne, 46% moderate acne and 32% had severe acne. Patients with severe acne had significantly lower plasma zinc levels (60.2 ± 10.4 µg/dL) compared to those with mild acne (73.1 ± 13.1 µg/dL) (p &lt; 0.01). Pearson’s correlation analysis revealed a significant inverse relationship between plasma zinc status and acne severity (r = -0.43, p &lt; 0.001), indicating that lower zinc levels were associated with more severe acne. No significant gender differences were observed in the relationship between zinc levels and acne severity. Conclusion: Pasma Zn concentration is markedly decreased in patients with AV and the more severe is the lesion, the more Hypozincemia. Hence, Plasma Zn status is associated negatively with severity of AV lesions in the studied population.

Synthesis of porous functional biochar through template method and plasma modification for Pb2+ removal: Performance and mechanism

Rich pore structures and functional groups are crucial for adsorbents used for heavy metal removal. In this study, porous functional biochar from corn straw was synthesized using a zinc template method and plasma modification. The impact of synthesis and adsorption conditions on Pb2+ removal by porous biochar was investigated, and the mechanism was elucidated. The results demonstrated that porous biochar prepared at 600 °C, with a biomass-to-template ratio of 3:1, heating rate of 10 oC/min and further modification by steam plasma (60 kV, water vapor content of 1 %, 5 min) achieved a remarkable Pb2+ removal efficiency of 90.94 % in aqueous solutions, with an adsorption capacity of 87.2 mg/g. During adsorption, some Pb2+ was reacted with C-OH groups on the biochar to form Pb(OH)2, while the remaining Pb2+ was transferred to PbCO3 through reactions with ZnO in the biochar and soluble CO2 in water. This indicated that ZnO particles and C-OH functional groups generated through plasma modification and the template method on the surface of biochar were primarily responsible for Pb2+ removal. Both methods effectively enhanced the adsorption and removal performance of the biochar.

Zinc Deficiency and Post-acute Outcomes in Patients With COVID-19: A Six-Month Retrospective Cohort Analysis of 3,726 Patients.

Background Previous studies have suggested that zinc deficiency (ZD) may increase the risk of short-term mortality in patients with coronavirus disease 2019 (COVID-19). However, the relationship between zinc status and post-acute COVID-19 outcomes remains unclear. This study aimed to determine the association between ZD and long-term outcomes in patients with COVID-19. Methodology We conducted a retrospective cohort study using the TriNetX database, including patients aged 18 years or older diagnosed with COVID-19 between January 1, 2022, and July 31, 2023. Patients had documented serum or plasma zinc levels within three months before COVID-19 diagnosis and were not deceased or hospitalized in the first month of infection. They were categorized into ZD (zinc levels <70 μg/dL) and control (zinc levels ≥70 μg/dL) groups. After 1:1 propensity score matching for demographic and clinical variables, outcomes were assessed from 30 to 180 days post-diagnosis, including all-cause hospitalization, all-cause mortality, and four subphenotypes of post-acute COVID-19. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. Results After matching, each group included 1,863 patients with balanced baseline characteristics. The ZD group had a higher incidence of all-cause hospitalization (25.3% vs. 20.3%; HR = 1.314; 95% CI = 1.148-1.505; p < 0.001) and all-cause mortality (3.8% vs. 2.2%; HR = 1.735; 95% CI = 1.180-2.551; p = 0.045) compared to the control group during the follow-up period. Among the four subphenotypes, only the cardiac and renal subphenotype showed a significantly higher risk in the ZD group (HR = 1.099; 95% CI = 1.002-1.205; p = 0.004). Conclusions ZD is associated with increased risks of long-term hospitalization, mortality, and increased risk in COVID-19 patients with cardiac and renal comorbidities. Monitoring and managing zinc levels may be important for improving long-term outcomes. Further research is warranted to explore the potential benefits of zinc supplementation in COVID-19 patients with ZD.

Plasma Zinc Levels in Patients with Diabetic Nephropathy: Is there a Relationship with NLRP3 Inflammasome Activation and Renal Prognosis?

Zinc is an essential trace element, and impaired zinc homeostasis may be associated with inflammation in patients with diabetic nephropathy (DN). We investigated the influence of zinc level on nod-like receptor nucleotide-binding domain and leucine-rich repeat pyrin-3 domain (NLRP3) inflammasome expression and renal prognosis in patients with DN. We recruited 90 patients definitively diagnosed with DN by renal biopsy and 40 healthy controls. Zinc, NLRP3, interleukin (IL)-1β, and IL-18 levels were detected in blood samples, and the correlations between these parameters were assessed. Receiver operating characteristic (ROC) curve and decision curve analysis (DCA) evaluated the predictive value of zinc and the NLRP3 inflammasome for DN. Furthermore, patients with DN were divided into low- and normal-zinc groups to observe differences in clinical indicators and identify expression of inflammatory-related factors in renal tissue. Kaplan-Meier survival curves predicted the impact of zinc levels on renal prognosis. We found thatthe plasma zinc concentration in patients with DN was lower, while NLRP3, IL-1β, and IL-18 levels were higher than were those in patients without DN (P < 0.05). Zinc level was negatively correlated with NLRP3, IL-1β, and IL-18 levels (P < 0.01). Zinc and the NLRP3 inflammasome were predictive of DN, but their combination improved the diagnostic value. The DCA curve demonstrated a good positive net benefit in the combined model. Compared to patients with low zinc levels, patients with normal zinc levels had lower expression of NLRP3 inflammasome and a better prognosis. Zinc has a protective effect on DN and may affect NLRP3 inflammasome activation.

Metabolomic changes in tear fluid following zinc biofortification in the BiZiFED nutritional study: a feasibility study.

Biofortified Zinc Flour to Eliminate Deficiency in Pakistan (BiZiFED) is a nutritional research program that evaluates the impact of consuming zinc biofortified wheat flour on zinc status and associated health outcomes of vulnerable communities in northwest Pakistan. Measuring zinc status from blood samples is fraught with problems. This feasibility study evaluated whether metabolite changes in tear biofluids could be used to understand zinc status. Zinc deficiency is particularly prevalent amongst the female population in Pakistan. Therefore, a crossover trial was developed in which 25 women of reproductive age received standard, wheat flour, and another 25 received zinc-biofortified wheat flour for 8 weeks. At the end of this period, the nutritional intervention was switched between the groups for another 8 weeks. Tear biofluid was collected using Schirmer strips at baseline and after 8 and 16 weeks. Metabolomic analysis was conducted using the MxP® Quant 500 kit on the tear biofluid from a subset of the study participants. Two metabolites had a significantly negative correlation with plasma zinc concentration: tiglylcarnitine and valine. Compared to baseline metabolite concentrations, acetylcarnitine, glutamine, two lysophosphatidylcholines (lysoPC a C16:0 and lysoPC a C18:1), and four sphingomyelins (SM (OH) C16:1, SM C16:0, SM C16:1, and SM C24:0) were all significantly decreased post-zinc intervention, whilst a ceramide (Cer(d18:1/18:0) was significantly increased. These results highlight the potential of using tear biofluids as an alternative source for metabolomic biomarkers, both for the assessment of the zinc status of individuals enrolled in nutritional studies and for indicating physiological changes that arise from nutritional supplementation.

Association of seminal plasma zinc levels with human semen quality and its toxic effects on sperm motility

Infertility has become one of the most common chronic diseases among reproductive- aged individuals, and male factors account for about 50 %. Zinc is a trace element that is essential for sperm quality and male reproductive system. Although several current studies with small sample sizes have investigated this relationship, the conclusions have been still controversial. Here, using a large population sample involved 25,915 participants from Changzhou Maternity and Child Health Care Hospital, we revealed an inverted “U”-shaped trend between seminal plasma zinc concentrations and sperm motility PR/PR + NP (PR, progressive motility; NP, non-progressive motility). The results showed that the highest values of sperm PR/PR + NP observed in the group with intermediate concentrations of zinc (Group 2, 0.25–2.11 mmol/L). The mean values were 43.17 ± 19.03 % and 56.64 ± 20.28 %, respectively. And the lowest values came out in the highest zinc levels group (Group 4, > 3.04 mmol/L). In vitro cell experiments also showed that zinc caused dose-dependent cytotoxicity for GC-2 cells at a threshold value. Furthermore, RNA-seq analysis demonstrated that high concentrations of zinc exerted toxic effects on GC-2 cells through immune injury. Taken together, our findings suggested that moderate amounts of zinc are crucial for human reproduction and excessive concentrations may have adverse effects on male fertility.

Plasma, Urinary, Erythrocyte and Platelet Zinc Concentrations in Soccer Players.

Essential trace minerals are vital for general human health and athletic performance. Zinc (Zn) plays critical roles in several biochemical processes in exercise physiology, especially during intense physical exercise. This research aimed to analyze erythrocyte, platelet, plasma and urine Zn concentrations among men's and female soccer players over a sports season. A total of 22 male soccer players (20.61 ± 2.66 years; 71.50 ± 5.93 kg) and 24 female soccer players (23.37 ± 3.95 years; 59.58 ± 7.17 kg) participated in this longitudinal quasi-experimental study. Three assessments were carried out over the season: 1st evaluation: first week of training (August); 2nd assessment: middle of the season, between the end of the first and second round (January) and 3rd assessment: last week of training (May/June). In all evaluations extracellular (plasma and urine) and intracellular (erythrocytes and platelets) Zn concentrations were determined, as well as physical fitness and several blood parameters. Inductively coupled plasma mass spectrometry was used to measure Zn concentrations. Plasma and urinary concentrations were higher among male soccer players (p < 0.05) while erythrocyte and platelet Zn concentrations were higher in the female soccer players (p < 0.05). Additionally, variations in urinary and platelet Zn concentrations were observed over the season. The differences could be related to muscle mass, muscle damage or the specific sport's physical demands.

Effect of Zinc and Vitamin E on Blood Testosterone and Inflammatory Markers in Male Patients Undergoing Heart Surgery

Background: Zinc and vitamin E affect the metabolism of testosterone and inflammatory factors. We aimed to evaluate the effect of zinc and vitamin E supplementation on plasma testosterone levels and inflammatory markers in patients undergoing coronary artery bypass graft (CABG) surgery. Methods: This study was a secondary analysis of a previously published randomized controlled trial in a subsample of male patients undergoing CABG surgery. Patients in the zinc-vitamin E group (n = 27) received oral zinc (120 mg) and vitamin E (1200 international units) one day prior to surgery, followed by 30 mg of zinc and 200 units of vitamin E per day for three weeks after surgery. Patients in the control group (n = 25) received a placebo. Plasma levels of total testosterone, cortisol, interleukin-6 (IL-6), and white blood cell toll-like receptor-4 (TLR-4) gene expression were determined at three-day and three-week intervals following surgery. Changes in these markers were analyzed using a repeated-measures analysis of variance. Results: A comparison of the groups revealed no significant difference in the concentration of plasma total testosterone levels (P = 0.059) or cortisol. Three weeks following the surgical procedure, a positive correlation was observed between the change in plasma zinc concentrations and the change in plasma testosterone levels (r = 0.32; P = 0.025). The administration of zinc and vitamin E supplements resulted in a reduction in plasma IL-6 levels on postoperative day 3 (P = 0.025), while no significant effect was observed in week 3 (P = 0.091). The expression of the TLR-4 gene in WBCs was found to be lower in the zinc-vitamin E group compared to the placebo group on day 3 (P = 0.051) and week 3 (P = 0.025). Conclusions: The administration of zinc and vitamin E to patients undergoing CABG was associated with a relative improvement in postoperative inflammatory markers. Plasma zinc levels demonstrated a correlation with testosterone levels, suggesting a potential avenue for further research in these patients.

Low thiamine status in adults following low-carbohydrate / ketogenic diets: a cross-sectional comparative study of micronutrient intake and status.

Low-carbohydrate diets (LCD) are popular for weight loss but lack evidence about micronutrient sufficiency in real-life use. This study assessed the intake and biochemical status of selected micronutrients in people voluntarily following LCDs. A cross-sectional study was conducted (2018-20) among 98 adults recruited as self-reporting either LCD (n = 49) or diets not restricting carbohydrates (controls; n = 49). Diets were assessed using the 130-item EPIC-Norfolk food-frequency questionnaire. Red-blood-cell thiamine diphosphate (TDP) was measured for thiamine status using HPLC. Plasma magnesium, zinc, copper, and selenium were measured using inductively coupled plasma mass spectrometry. Between-group biomarker comparisons were conducted using ANCOVA and adjusted for age, sex, body mass index (BMI), and diabetes status. LCD-followers (26% male, median age 36 years, median BMI 24.2 kg/m2) reported adhering to LCDs for a median duration of 9 months (IQR 4-36). The most followed LCD type was 'their own variations of LCD' (30%), followed by ketogenic (23%), 'palaeolithic' (15%), and Atkins diets (8%). Among controls, 41% were male (median age 27 years, median BMI 23kg/m2). Median macronutrient intakes for LCD vs control groups were carbohydrate 16%Energy (E) vs. 50%E; protein 25%E vs. 19%E; and fat 55%E vs 34%E (saturated fat 18%E vs. 11%E). Two-thirds of LCD followers (32/49) and half of the controls (24/49) reported some use of dietary supplements (p = 0.19). Among LCD-followers, assessing from food data only, 21 (43%) failed to meet the reference nutrient intake (RNI) for thiamine (vs.14% controls, p = 0.002). When thiamine from supplementation (single- or multivitamin) was included, there appeared to be no difference in thiamine intake between groups. Still, red-blood-cell TDP was lower in LCD-followers than controls (407 ± 91 vs. 633 ± 234 ng/gHb, p < 0.001). Three LCD-followers were thiamine-deficient (RBC thiamine < 275 ng/gHb) vs. one control. There were no significant differences in dietary intakes or plasma concentrations of magnesium, zinc, copper, and selenium between groups. Following LCDs is associated with lower thiamine intake and TDP status than diets without carbohydrate restriction, incompletely corrected by supplement use. These data, coupled with a lack of RCT evidence on body weight control, do not support recommending LCDs for weight management without appropriate guidance and diet supplementation.

Hematological toxicity of disinfection by-product iodoacetic acid

To clarify the effect of iodoacetic acid(IAA) on the blood system and electrolyte balance, hence further study the intrinsic relation of blood routine parameters and electrolyte levels, major hematological toxicity effects and their pattern after IAA treatment. Forty-eight 21-day-old male SPF grade Sprague-Dawley(SD) rats were gavaged with 0, 6.25, 12.5 and 25 mg/kg IAA for 31 days. After detections of blood routine and plasma inorganic ion levels, Spearman correlation coefficients were performed to evaluate their relationship. Changes in ferritin, transferrin, hepcidin, C-reactive protein and glyceraldehyde-3-phosphate dehydrogenase(GAPDH) were assessed by enzyme-linked immunosorbent assays. The EDock bioinformatics tool was applied to docking model of IAA and GAPDH. Compared to the control, high-dose IAA exposure had obvious inhibition effect on rat leukocytes with the total number declined by 51.12%, and neutrophils were particularly sensitive to IAA with the number reduced by 73.66%(P&lt;0.01), and rat erythrocytes exhibited a small cell low pigment effect with hemoglobin and hematocrit decreased by 8.60% and 8.70%, respectively(P&lt;0.05). But IAA had little effects on the platelet. Plasma iron, phosphorus, zinc and potassium levels were repressed significantly, while chlorine, sodium and magnesium levels were elevated obviously through IAA exposure. However, plasma calcium levels were hardly affected by IAA. In comparison with the control, iron levels declined by 67.09%, whereas magnesium levels increased by 131.82% in the high-dose group(P&lt;0.01). Overall, correlation analyses uncovered that plasma iron metabolism was most strongly and positively correlated with levels of leukocyte, erythrocyte and platelet system parameters after IAA exposure, and the correlation coefficients of leukocyte number, mean hemoglobin content and mean erythrocyte volume were 0.637, 0.410 and 0.365, respectively(P&lt;0.05). Compared to the control, in the high-dose IAA group, the plasma content of C-reactive protein was significantly upregulated by 13.30%(P&lt;0.05), and plasma levels of transferrin and ferromodulin were also respectively elevated by 12.73% and 11.02%(P&lt;0.05). But plasma levels of ferritin and GAPDH did not differ between groups. The docking model exhibited that IAA could bind to the 150 Cys active site of rat GAPDH did. IAA not only had toxic effects on rat leukocytes and the plasma electrolyte balance, but also generated inflammation and iron deficiency, leading to smaller erythrocytes and lower pigment.

A Fluorometric Method for Zinc Estimation: Applications in the Estimation of Plasma Zinc and in Assessing Zinc Bioaccessibility from Rice.

Sensitive and precise methods for the estimation of zinc (Zn) in biological fluids and foods are important tools in understanding the various aspects related to Zn nutrition. Estimation of serum/plasma Zn was suggested for assessing the population Zn status while assessing the bioaccessible Zn following simulated gastrointestinal digestion of crop varieties such as rice helps in ranking the crops. Atomic absorption spectrometry (AAS) or inductively coupled plasma-mass spectrometry (ICP-MS) are widely used for Zn estimation. Zinquin, a Zn fluorophore, has been used for the localization of cellular Zn and labile Zn pools in biological fluids with extremely high sensitivity. However, it was not tested for its use in Zn estimation in serum/plasma or in assessing the Zn bioaccessibility from foods. In the current study, we demonstrate a sensitive method for Zn estimation in human plasma and validate it against the reference method (AAS) by comparing the paired measurements on the same samples. The method-related bias between zinquin with AAS was negligible (0.48µg/dL), and the precision (CV) of the assay was < 5% across different Zn concentrations. In addition, we also demonstrated the utility of zinquin assay in estimating the bioaccessibility of Zn from rice varieties and showed that the method is again comparable to AAS. The zinquin method is capable of discriminating the differences in zinc bioaccessibility between polished and unpolished rice varieties. In the context of required lowplasma volume (100µL Vs 400µL), excellent comparability of the results with the reference method and analytical simplicity could be particularly useful.

Strategies for Inducing and Validating Zinc Deficiency and Zinc Repletion

Background: According to the World Health Organization, zinc deficiency is a growing global health problem, impacting 31% of the world’s population. Zinc deficiency is a common comorbidity with many chronic diseases, from skin to kidney diseases. Given the increasing interest in zinc’s role in disease onset and progression, there is a dire need for reproducible approaches to manipulate zinc homeostasis. Here, we provide proven strategies for inducing and validating zinc deficiency and zinc repletion in a mouse model. Experimental Design: After acclimating to a ZnA (zinc adequate) diet, mice are randomly assigned to either a ZnA or ZnD (zinc deficient) diet. To replete zinc levels (ZnR), a subset of ZnD mice is returned to the ZnA diet. Animal growth rates and plasma zinc levels are assessed to validate zinc status. Results: Mice placed on the ZnD-diet have reduced body weights (26.48g ± 0.78) compared to mice maintained on the ZnA-diet (28.12g ± 0.13). However, zinc repletion promotes weight gain (27.87g ± 1.01) resulting in body weights comparable to mice maintained on the ZnA-diet. Furthermore, mice maintained on the ZnA-diet have plasma zinc levels of 3.19 μM/g Body Weight. While plasma zinc levels are 40% lower in mice place on the ZnD-diet (1.29 μM/g Body Weight). In contrast, plasma zinc levels (2.44 μM/g Body Weight) are increased in ZnR mice. Conclusion: These findings validate that the described dietary approach is an effective strategy for inducing zinc deficiency and zinc repletion. Significance: This cost-effcient approach will enhance the scientific rigor and reproducibility of studies examining the impact of zinc deficiency, and repletion on disease onset and progression. Funding Source: R21 DK119879, R01 DK-133698. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Changes in Nutritional Outcomes After Roux-en-Y Gastric Bypass: A Systematic Review and Meta-Analysis.

Bariatric surgery (BS) is the most effective treatment for severe obesity and it has beneficial effects on glycemic control and metabolism outcomes. However, the effects of BS on nutritional outcomes are controversial. Therefore, we aimed to evaluate the changes in several nutritional outcomes after Roux-en-Y gastric bypass (RYGB). A comprehensive search was performed using the following databases: PubMed, Embase, Web of Science, Cochrane Library, WanFang and Chinese National Knowledge Infrastructure. The following outcomes were evaluated: vitamin A, 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, parathormone (PTH), iron, ferritin, vitamin B12, folate, and zinc. The pooled outcomes were expressed as standard mean difference (SMD) and 95% confidence interval (CI) using a random effects model. Fifty-six studies including 5645 individuals with obesity met the inclusion criteria. Serum 25(OH)D (SMD = 0.78, 95%CI 0.38 to 1.20, P < 0.001), phosphorus (SMD = 0.48, 95%CI 0.22 to 0.74, P < 0.001), PTH (SMD = 0.35, 95%CI 0.11 to 0.59, P = 0.005), vitamin B12 (SMD = 1.11, 95%CI 0.41 to 1.80, P = 0.002), and folate (SMD = 1.53, 95%CI 0.77 to 2.28, P < 0.001) significantly increased after RYGB compared with the baseline. Serum ferritin (SMD = - 1.67, 95%CI - 2.57 to - 0.77, P < 0.001), vitamin A (SMD = - 0.64, 95%CI - 0.99 to - 0.29, P < 0.001), and plasma zinc (SMD = - 0.58, 95%CI - 1.09 to - 0.06, P = 0.027) significantly decreased after RYGB. No significant changes in serum calcium (SMD = - 0.14, 95%CI - 0.40 to 0.11, P = 0.219) and iron (SMD = 0.26, 95%CI - 0.11 to 0.64, P = 0.165) were observed after RYGB. Despite the increased levels of 25(OH)D, phosphorus, vitamin B12 and folate, this meta-analysis revealed the unfavorable nutritional consequences after RYGB.