Lower zinc bioavailability may be related to higher risk of subclinical atherosclerosis in Korean adults

Habitual intake of iron, copper, and zinc and the risk of type 2 diabetes in a prospective cohort: The CAVAS (Cardiovascular Disease Association Study)

BACKGROUND AND AIMS

Unlike iron, evidence of the association between dietary copper and zinc intake and type 2 diabetes (T2D) risk is limited. This study aimed to examine the prospective associations of dietary intake of iron (total, plant-based, and animal-based), copper, and zinc with T2D risk among adults aged ≥40 years.

METHODS AND RESULTS

For 16,666 participants, dietary intakes (baseline, cumulative average, and most recent) of iron, copper, and zinc were calculated from repeated food frequency questionnaires; a modified Poisson regression model with a robust error estimator was conducted. In men, positive associations between T2D and baseline dietary intake of Cu and Zn, cumulative average dietary intake of Fe (total and animal-based), Cu and Zn, and most recent dietary intake of Fe (total, plant-based, and animal-based), Cu, and Zn [most recent diet: for total Fe, IRR(95%CI) = 1.93 (1.41-2.64); for plant-based Fe, 1.56 (1.15-2.11); for animal-based Fe, 1.44 (1.09-1.90); for Cu, 3.17 (2.33-4.30); for Zn, 2.18 (1.64-2.89)] were observed, where as in women, there were positive associations of only cumulative average dietary Zn intake and most recent dietary intake of plant-based Fe, Cu, and Zn [most recent diet: for plant-based Fe, 1.30 (1.01-1.68); for Cu, 1.62 (1.27-2.08); for Zn, 2.07 (1.61-2.66)].

CONCLUSION

Dietary intakes of iron (total, plant-based, and animal-based), copper, and zinc may be positively associated with T2D risk. These positive associations are predominantly observed in most recent diet and appear to be stronger compared to baseline and cumulative average diet.

Associations of Dietary Zinc-Vitamin B6 Ratio with All-Cause Mortality and Cardiovascular Disease Mortality Based on National Health and Nutrition Examination Survey 1999-2016

Previous studies have suggested a possible association among dietary zinc and vitamin B6 intake and CVD mortality and all-cause mortality. However, evidence on the association of dietary zinc and vitamin B6 intake and their interactions with CVD mortality and all-cause mortality remains unclear. This prospective study utilized data from the US National Health and Nutrition Examination Survey (NHANES) from 1999 to 2016. After a median follow-up of 10.4 years, 4757 deaths were recorded among 36,081 participants. Higher dietary zinc intake levels (≥9.87 mg/day) were associated with lower CVD mortality (hazard ratio (HR) = 0.85, 95% confidence interval (CI): 0.83−0.87). Vitamin B6 intake levels (≥1.73 mg/day) were associated with lower CVD mortality (HR = 0.91, 95% CI: 0.86−0.96) and all-cause mortality (HR = 0.91, 95% CI: 0.90−0.93). Higher dietary zinc intake and higher vitamin B6 intake were associated with a lower risk of CVD mortality, with an interaction between dietary zinc intake levels and vitamin B intake levels (LZLV group (HR, CI): 1.21,1.12−1.29; LZHV group (HR, CI): 1.42, 1.34−1.50; LZHV group (HR, CI): 1.28, 1.14−1.45; HZHV group (HR, CI): ref). There was also a J-type association (p for nonlinear < 0.001) between the dietary zinc−vitamin B6 ratio and CVD mortality, with a high dietary zinc−vitamin B6 ratio increasing the risk of CVD mortality (HR = 1.27, 95% CI: 1.19−1.35), whereas a moderate dietary zinc−vitamin B6 ratio appeared to be beneficial for CVD mortality. These results suggest that increasing the appropriate proportion of dietary zinc and vitamin B6 intake is associated with a lower risk of CVD mortality. Furthermore, precise and representative studies are needed to verify our findings.

Comparison of zinc levels in the various biosubstrates of patients with unstable atherosclerotic plaque

The article describes the content and comparative characteristics of zinc level in the hair, biopsies of carotid atherosclerotic plaques (AP) and serum in patients with carotid atherosclerosis. The highest concentration of zinc is found in hair compared to the AP and serum. Zinc levels is higher in AP than in the serum. It is noteworthy that the level of zinc in biopsies of unstable AP was lower compared to the level of zinc in hair.

Significant Nutritional Gaps in Tibetan Adults Living in Agricultural Counties Along Yarlung Zangbo River

Background

Dietary intake and nutritional assessing data from a representative sample of adult population living in an agricultural zone on Tibet Plateau are still lacking nowadays. This study aimed to assess the daily dietary intakes and respective food sources in 552 local residents (≥ 18 years old, 277 men and 275 women) living in 14 agricultural counties along the Yarlung Zangbo River on Tibet Plateau.

Methods

Food consumption data were collected using a validated cultural-specific food frequency questionnaire that contained all local Tibetan foods and analyzed with three fixed factors: gender, age, and region. Nutrient intakes were calculated using Chinese food composition tables. Nutritional gaps and the percentages of participants who had inadequate and excessive nutrient intakes were calculated by estimated average requirement (EAR) cut-point methods.

Results

Compared with the dietary reference intakes, 68.4% of nutrient intakes were inadequate. Fiber, Ca, I, Zn, Se, and vitamin (Va, Vc, and folic acid) intakes appeared to be particularly deficient. The dietary energy intake was 7838.8 ± 537.1 KJ/d, with 78 and 84% of EAR values for men and women, respectively. The dietary intakes of most nutrients were below the estimated energy requirement/EAR or adequate intake values, while more than 70% of the participants had excessive intake of carbohydrate, especially the elderly (aged ≥ 51 years). The nutritional gap of Cu was more than 300%. Almost 100% of the participants was vulnerable to fiber, Se, and Va shortfalls due to the deficiency in sole food sources. The top five food sources of Se intake were highland barley (34.2%), meat (13%), rice (12.4%), eggs (12.2%), and cultural-specific beverages (7.8%). Eggs (42.1%), tubers (62.2%), vegetables (66.4%), and highland barley (49.7%) were the first contributors of Va, Ve, Vc, and folic acid, respectively.

Conclusion

The dietary intake of a large sample of Tibetan adult population living in agricultural counties of Tibetan Autonomous Region is alarmingly insufficient. Gender inequality is common, and regional difference is widespread due to rapid urbanization. Young Tibetan adults aged 18–30 years are particularly vulnerable to micronutrient shortfalls and currently facing the risk of nutrition-insecurity-related dietary inadequacy. The respondents who belong to the elderly category (≥51 years of age) are facing the risk of “double burden of malnutrition” characterized by the coexistence of undernutrition, including micronutrient deficiencies and overweight or obesity.

Retrospective observational study evaluating zinc plasma level in patients undergoing thoracoabdominal aortic aneurysm repair and its correlation with outcome

Thoracoabdominal aortic aneurysm (TAAA) repair is related to a relevant morbidity and in-hospital mortality rate. In this retrospective observational single-center study including serum zinc levels of 33 patients we investigated the relationship between zinc and patients’ outcome following TAAA repair. Six patients died during the hospital stay (18%). These patients showed significantly decreased zinc levels before the intervention (zinc levels before intervention: 60.09 µg/dl [survivors] vs. 45.92 µg/dl [non-survivors]). The post-interventional intensive care SOFA-score (Sepsis-related organ failure assessment) (at day 2) as well as the SAPS (Simplified Acute Physiology Score) (at day 2) showed higher score points in case of low pre-interventional zinc levels. No significant correlation between patient comorbidities and zinc level before intervention, except for peripheral arterial disease (PAD), which was significantly correlated to reduced baseline zinc levels, was observed. Septic shock, pneumonia and urinary tract infections were not associated to reduced zinc levels preoperatively as well as during therapy. Patients with adverse outcome after TAAA repair showed reduced pre-interventional zinc levels. We speculate that decreased zinc levels before intervention may be related to a poorer outcome because of poorer physical status as well as negatively altered perioperative inflammatory response.

The Associated Regulatory Mechanisms of Zinc Lactate in Redox Balance and Mitochondrial Function of Intestinal Porcine Epithelial Cells

Zinc lactate (ZnLA) is a new organic zinc salt which has antioxidant properties in mammals and can improve intestinal function. This study explored the effects of ZnLA and ZnSO₄ on cell proliferation, Zn transport, antioxidant capacity, mitochondrial function, and their underlying molecular mechanisms in intestinal porcine epithelial cells (IPEC-J2). The results showed that addition of ZnLA promoted cell proliferation, inhibited cell apoptosis and IL-6 secretion, and upregulated the mRNA expression and concentration of MT-2B, ZNT-1, and CRIP, as well as affected the gene expression and activity of oxidation or antioxidant enzymes (e.g., CuZnSOD, CAT, and Gpx1, GSH-PX, LDH, and MDA), compared to ZnSO₄ or control. Compared with the control, ZnLA treatment had no significant effect on mitochondrial membrane potential, whereas it markedly increased the mitochondrial basal OCR, nonmitochondrial respiratory capacity, and mitochondrial proton leakage and reduced spare respiratory capacity and mitochondrial reactive oxygen (ROS) production in IPEC-J2 cells. Furthermore, ZnLA treatment increased the protein expression of Nrf2 and phosphorylated AMPK, but reduced Keap1 and p62 protein expression and autophagy-related genes LC3B-1 and Beclin mRNA abundance. Under H₂O₂-induced oxidative stress conditions, ZnLA supplementation markedly reduced cell apoptosis and mitochondrial ROS levels in IPEC-J2 cells. Moreover, ZnLA administration increased the protein expression of Nrf2 and decreased the protein expression of caspase-3, Keap1, and p62 in H₂O₂-induced IPEC-J2 cells. In addition, when the activity of AMPK was inhibited by Compound C, ZnLA supplementation did not increase the protein expression of nuclear Nrf2, but when Compound C was removed, the activities of AMPK and Nfr2 were both increased by ZnLA treatment. Our results indicated that ZnLA could improve the antioxidant capacity and mitochondrial function in IPEC-J2 cells by activating the AMPK-Nrf2-p62 pathway under normal or oxidative stress conditions. Our novel finding also suggested that ZnLA, as a new feed additive for piglets, has the potential to be an alternative for ZnSO₄.

Dietary antioxidant intake decreases carotid intima media thickness in women but not in men: A cross-sectional assessment in the Kardiovize study

OBJECTIVE

Atherosclerosis is a major contributor to cardiovascular disease, with a higher burden on men than women during the occupational age. Intake of individual dietary antioxidants is inversely associated with risk of atherosclerosis development. We aimed to understand the relationship between dietary composite antioxidant intake and the carotid intima media thickness (cIMT), which is a proxy of atherosclerosis progression.

APPROACH AND RESULTS

We performed a cross-sectional analysis that included 894 members of the Kardiovize cohort, a random urban sample population. Nutrient intakes were derived by 24-h recall. We constructed a composite dietary antioxidant index (CDAI), based on zinc, selenium, vitamin A, vitamin C, vitamin E and carotenoids. We considered the CDAI as the exposure variable and primary outcomes were the following cardio-metabolic parameters: body mass index (BMI), waist-to-hip ratio (WHR), body fat mass (BFM), systolic and diastolic blood pressure, triglycerides, HDL and LDL cholesterol, and cIMT. Associations and interactions between variables were evaluated using linear regression analyses. In women, a 1 mg increase in dietary intake of zinc or vitamin E decreased the cIMT by 3.36 and 1.48 µm, respectively, after adjusting for covariates. Similarly, the cIMT decreased by 4.72 µm for each one-unit increase in CDAI (p = 0.018). Beyond CDAI, age (β = 3.61; SE=0.89; p = 0.001), systolic blood pressure (β = 1.30; SE=0.59; p = 0.029) and triglycerides (β = 22.94; SE=10.09; p = 0.024) were significant predictors of cIMT in women. By contrast, we found no association between CDAI and cIMT in men.

CONCLUSIONS

CDAI negatively associates with cIMT in women. These findings indicate that combined intake of nutrients with anti-oxidant properties might prevent the initiation and progression of arterial lesions in a sex-specific manner.

Zinc Inhibits Phosphate-Induced Vascular Calcification through TNFAIP3-Mediated Suppression of NF-κB

Background The high cardiovascular morbidity and mortality of patients with CKD may result in large part from medial vascular calcification, a process promoted by hyperphosphatemia and involving osteo-/chondrogenic transdifferentiation of vascular smooth muscle cells (VSMCs). Reduced serum zinc levels have frequently been observed in patients with CKD, but the functional relevance of this remains unclear.Methods We performed experiments in primary human aortic VSMCs; klotho-hypomorphic (kl/kl), subtotal nephrectomy, and cholecalciferol-overload mouse calcification models; and serum samples from patients with CKD.Results In cultured VSMCs, treatment with zinc sulfate (ZnSO₄) blunted phosphate-induced calcification, osteo-/chondrogenic signaling, and NF-κB activation. ZnSO₄ increased the abundance of zinc-finger protein TNF-α-induced protein 3 (TNFAIP3, also known as A20), a suppressor of the NF-κB pathway, by zinc-sensing receptor ZnR/GPR39-dependent upregulation of TNFAIP3 gene expression. Silencing of TNFAIP3 in VSMCs blunted the anticalcific effects of ZnSO₄ under high phosphate conditions. kl/kl mice showed reduced plasma zinc levels, and ZnSO₄ supplementation strongly blunted vascular calcification and aortic osteoinduction and upregulated aortic Tnfaip3 expression. ZnSO₄ ameliorated vascular calcification in mice with chronic renal failure and mice with cholecalciferol overload. In patients with CKD, serum zinc concentrations inversely correlated with serum calcification propensity. Finally, ZnSO₄ ameliorated the osteoinductive effects of uremic serum in VSMCs.Conclusions Zinc supplementation ameliorates phosphate-induced osteo-/chondrogenic transdifferentiation of VSMCs and vascular calcification through an active cellular mechanism resulting from GPR39-dependent induction of TNFAIP3 and subsequent suppression of the NF-κB pathway. Zinc supplementation may be a simple treatment to reduce the burden of vascular calcification in CKD.

Effects of zinc supplementation on catch-up growth in children with failure to thrive

BACKGROUND/OBJECTIVES

Although globally the numbers of children diagnosed with failure to thrive (FTT) have decreased, FTT is still a serious pediatric problem. We aimed to investigate the effects of zinc supplementation for 6 months on growth parameters of infants and children with FTT.

SUBJECTS/METHODS

In this retrospective study, of the 114 participants aged between 4 months and 6 years, 89 were included in the zinc supplementation group and were provided with nutrition counseling plus an oral zinc supplement for 6 months. The caregivers of the 25 participants in the control group received nutrition counseling alone. Medical data of these children, including sex, age, height, weight, serum zinc level, and serum insulin-like growth factor 1 (IGF1) level were analyzed.

RESULTS

Zinc supplementation for 6 months increased weight-for-age Z-score and serum zinc levels (5.5%) in the zinc supplementation group of underweight category children. As for stunting category, height-for-age Z-score of the participants in the zinc supplementation group increased when compared with the baseline, and serum zinc levels increased in the normal or mild stunting group. Serum IGF1 levels did not change significantly in any group. Thus, zinc supplementation was more effective in children in the underweight category than those in the stunted category; this effect differed according to the degree of the FTT.

CONCLUSION

These findings suggest that zinc supplementation may have beneficial effects for growth of infants and children with FTT, and zinc supplementation would be required according to degree of FTT.

The Relationship between Zinc Status and Inflammatory Marker Levels in Rural Korean Adults Aged 40 and Older

BACKGROUND

Serum cytokines and C-reactive protein (CRP) are known as one of the major risk factors in atherosclerosis. The antioxidant and anti-inflammatory properties of zinc have been suggested, but few data are available on the relationship between zinc status and inflammatory markers in epidemiological studies.

OBJECTIVE

The present study aims to investigate the cross-sectional relationships of serum cytokines and CRP with dietary zinc intake and serum zinc levels in healthy men and women aged 40 and older in rural areas of South Korea.

MATERIALS AND METHODS

A group of 1,055 subjects (404 men, 651 women) was included in dietary zinc analysis while another group of 695 subjects (263 men, 432 women) was included in serum zinc analysis. Serum IL-6, TNF-α, and CRP were measured as inflammatory markers.

RESULTS

There was no significant inverse relationship between dietary zinc intake and inflammatory markers. We found a significant inverse relationship between serum zinc levels and all three inflammatory markers in women (P for trend = 0.0236 for IL-6; P for trend = 0.0017 for TNF-α; P for trend = 0.0301 for CRP) and between serum zinc levels and a single inflammatory marker (IL-6) in men (P for trend = 0.0191), although all R2 values by regression were less than 10%.

CONCLUSION

In conclusion, serum zinc levels may be inversely related to inflammatory markers (IL-6, TNF-α, and CRP), particularly in women.

Electrospun antimicrobial hybrid mats: Innovative packaging material for meat and meat-products

To prevent the development and spread of spoilage/pathogenic microorganisms via meat foodstuffs, antimicrobial nanocomposite packaging can serve as a potential alternative. The objective of this study was to develop a new class of antimicrobial hybrid packaging mat composed of biodegradable polyurethane supplemented with virgin olive oil and zinc oxide via electrospinning. Instead of mixing antimicrobial compounds directly with food, incorporation in packaging materials allows the functional effect at food surfaces where microbial activity is localized. The nanofibers were characterized by SEM, EDX, XRD and TEM. The antibacterial activity was tested against two common foodborne pathogens viz., Staphylococcus aureus and Salmonella typhimurium. The present results indicated that incorporation of olive oil in the polymer affected morphology of PU nanofibers and nanocomposite packaging were able to inhibit growth of pathogens. Thus; as-spun mat can be used as prospective antimicrobial packaging, which potentially reduces contamination of meat/meat-products. Moreover, introduced biodegradable packaging for meat products could serve to replace PVC films and simultaneously help to protect natural environment.