1
|
Rios-Leyvraz M, Yao Q. Calcium, zinc, and vitamin D in breast milk: a systematic review and meta-analysis. Int Breastfeed J 2023; 18:27. [PMID: 37264448 PMCID: PMC10233556 DOI: 10.1186/s13006-023-00564-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 05/20/2023] [Indexed: 06/03/2023] Open
Abstract
BACKGROUND Global estimates of calcium, zinc and vitamin D content in breastmilk are lacking. The objective of this systematic review was to determine the calcium, zinc, and vitamin D content in breast milk. METHODS A systematic search of the online databases Embase, MEDLINE, and CENTRAL was conducted in November 2022 and complemented by searches of the African Journals Online database and the LILACS database, and reference lists. Studies reporting the calcium, zinc and vitamin D content in breast milk of apparently healthy mothers and infants were included. Random effects meta-analyses were conducted. The effect of influencing factors were investigated with sub-group analyses and meta-regressions. RESULTS A total of 154 studies reporting on breast milk calcium were identified, with a mean calcium concentration in breast milk of 261 mg/L (95% CI: 238, 284). Calcium concentration was influenced by maternal health and decreased linearly over the duration of lactation. Calcium concentration at a specific time during lactation could be estimated with the equation: calcium concentration [mg/L] = 282 - 0.2331 ✕ number of days since birth. A total of 242 studies reporting on breast milk zinc were identified, with a mean zinc concentration of 2.57 mg/L (95% CI: 2.50, 2.65). Zinc concentration was influenced by several factors, such as maternal age, gestational age, and maternal diet. Zinc concentration started high in the first weeks post-partum followed by a rapid decrease over the first months. Zinc concentration at a specific time during lactation could be estimated with the equation: zinc concentration [mg/L] = 6 + 0.0005 ✕ days - 2.0266 ✕ log(days). A total of 43 studies reporting on breast milk vitamin D were identified, with a mean total antirachitic activity of breast milk of 58 IU/L (95% CI: 45, 70), which consisted mostly of 25OHD3, and smaller amounts of vitamin D3, 25OHD2 and vitamin D2. Vitamin D concentration showed wide variations between studies and was influenced by vitamin D supplementation, continent and season. CONCLUSIONS This review provides global estimates of calcium, zinc and vitamin D content in breast milk, as well as indications on changes over time and depending on influencing factors.
Collapse
Affiliation(s)
- Magali Rios-Leyvraz
- Consultant, Department of Nutrition and Food Safety, World Health Organization, Geneva, Switzerland
| | - Qisi Yao
- Department of Nutrition and Food Sciences, University of Rhode Island, Kingston, USA
| |
Collapse
|
2
|
Role of zinc in neonatal growth and brain growth: review and scoping review. Pediatr Res 2021; 89:1627-1640. [PMID: 33010794 DOI: 10.1038/s41390-020-01181-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 09/14/2020] [Accepted: 09/18/2020] [Indexed: 12/11/2022]
Abstract
This manuscript includes (1) a narrative review of Zinc as an essential nutrient for fetal and neonatal growth and brain growth and development and (2) a scoping review of studies assessing the effects of Zinc supplementation on survival, growth, brain growth, and neurodevelopment in neonates. Very preterm infants and small for gestational age infants are at risk for Zinc deficiency. Zinc deficiency can cause several complications including periorificial lesions, delayed wound healing, hair loss, diarrhea, immune deficiency, growth failure with stunting, and brain atrophy and dysfunction. Zinc is considered essential for oligodendrogenesis, neurogenesis, neuronal differentiation, white matter growth, and multiple biological and physiological roles in neurobiology. Data support the possibility that the critical period of Zinc delivery for brain growth in the mouse starts at 18 days of a 20-21-day pregnancy and extends during lactation and in human may start at 26 weeks of gestation and extend until at least 44 weeks of postmenstrual age. Studies are needed to better elucidate Zinc requirement in extremely low gestational age neonates to minimize morbidity, optimize growth, and brain growth, prevent periventricular leukomalacia and optimize neurodevelopment. IMPACT: Zinc is essential for growth and brain growth and development. In the USA, very preterm small for gestational age infants are at risk for Zinc deficiency. Data support the possibility that the critical period of Zinc delivery for brain growth in the mouse starts at 18 days of a 20-21-day pregnancy and extends during lactation and in human may start at 26 weeks' gestation and extend until at least 44 weeks of postmenstrual age. Several randomized trials of Zinc supplementation in neonates have shown improvement in growth when using high enough dose, for long duration in patients likely to or proven to have a Zinc deficiency. Studies are needed to better elucidate Zinc requirement in extremely low gestational age neonates to minimize morbidity, optimize growth and brain growth, prevent periventricular leukomalacia and optimize neurodevelopment.
Collapse
|
3
|
Golan Y, Assaraf YG. Genetic and Physiological Factors Affecting Human Milk Production and Composition. Nutrients 2020; 12:E1500. [PMID: 32455695 PMCID: PMC7284811 DOI: 10.3390/nu12051500] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 05/17/2020] [Accepted: 05/19/2020] [Indexed: 02/07/2023] Open
Abstract
Human milk is considered the optimal nutrition for infants as it provides additional attributes other than nutritional support for the infant and contributes to the mother's health as well. Although breastfeeding is the most natural modality to feed infants, nowadays, many mothers complain about breastfeeding difficulties. In addition to environmental factors that may influence lactation outcomes including maternal nutrition status, partner's support, stress, and latching ability of the infant, intrinsic factors such as maternal genetics may also affect the quantitative production and qualitative content of human milk. These genetic factors, which may largely affect the infant's growth and development, as well as the mother's breastfeeding experience, are the subject of the present review. We specifically describe genetic variations that were shown to affect quantitative human milk supply and/or its qualitative content. We further discuss possible implications and methods for diagnosis as well as treatment modalities. Although cases of nutrient-deficient human milk are considered rare, in some ethnic groups, genetic variations that affect human milk content are more abundant, and they should receive greater attention for diagnosis and treatment when necessary. From a future perspective, early genetic diagnosis should be directed to target and treat breastfeeding difficulties in real time.
Collapse
Affiliation(s)
| | - Yehuda G. Assaraf
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa 3200003, Israel;
| |
Collapse
|
4
|
Li Z, Wang J, Yang Y, Wang S. A novel homozygous mutation p.E88K in maternal
SLC30A2
gene as a cause of transient neonatal zinc deficiency. Exp Dermatol 2020; 29:556-561. [PMID: 32278324 DOI: 10.1111/exd.14099] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 02/26/2020] [Accepted: 04/01/2020] [Indexed: 02/05/2023]
Affiliation(s)
- Zhongtao Li
- Department of Dermatovenereology West China Hospital Sichuan University Chengdu China
| | - Jiayue Wang
- Department of Dermatovenereology West China Hospital Sichuan University Chengdu China
| | - Yuan Yang
- Department of Medical Genetics West China Hospital Sichuan University Chengdu China
| | - Sheng Wang
- Department of Dermatovenereology West China Hospital Sichuan University Chengdu China
| |
Collapse
|
5
|
Golan Y, Lehvy A, Horev G, Assaraf YG. High proportion of transient neonatal zinc deficiency causing alleles in the general population. J Cell Mol Med 2018; 23:828-840. [PMID: 30450693 PMCID: PMC6349188 DOI: 10.1111/jcmm.13982] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 09/25/2018] [Accepted: 10/02/2018] [Indexed: 01/01/2023] Open
Abstract
Loss of function (LoF) mutations in the zinc transporter SLC30A2/ZnT2 result in impaired zinc secretion into breast milk consequently causing transient neonatal zinc deficiency (TNZD) in exclusively breastfed infants. However, the frequency of TNZD causing alleles in the general population is yet unknown. Herein, we investigated 115 missense SLC30A2/ZnT2 mutations from the ExAC database, equally distributed in the entire coding region, harboured in 668 alleles in 60 706 healthy individuals of diverse ethnicity. To estimate the frequency of LoF SLC30A2/ZnT2 mutations in the general population, we used bioinformatics tools to predict the potential impact of these mutations on ZnT2 functionality, and corroborated these predictions by a zinc transport assay in human MCF-7 cells. We found 14 missense mutations that were markedly deleterious to zinc transport. Together with two conspicuous LoF mutations in the ExAC database, 26 SLC30A2/ZnT2 alleles harboured deleterious mutations, suggesting that at least 1 in 2334 newborn infants are at risk to develop TNZD. This high frequency of TNZD mutations combined with the World Health Organization-promoted increase in the rate of exclusive breastfeeding highlights the importance of genetic screening for inactivating SLC30A2/ZnT2 mutations in the general population for the early diagnosis and prevention of TNZD.
Collapse
Affiliation(s)
- Yarden Golan
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Adrian Lehvy
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Guy Horev
- Bioinformatics Knowledge Unit, The Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Yehuda G Assaraf
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| |
Collapse
|
6
|
In silico mapping of quantitative trait loci (QTL) regulating the milk ionome in mice identifies a milk iron locus on chromosome 1. Mamm Genome 2018; 29:632-655. [DOI: 10.1007/s00335-018-9762-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Indexed: 01/06/2023]
|
7
|
|
8
|
Genetic Variations as Modifying Factors to Dietary Zinc Requirements-A Systematic Review. Nutrients 2017; 9:nu9020148. [PMID: 28218639 PMCID: PMC5331579 DOI: 10.3390/nu9020148] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 02/09/2017] [Accepted: 02/13/2017] [Indexed: 12/30/2022] Open
Abstract
Due to reduced cost and accessibility, the use of genetic testing has appealed to health professionals for personalising nutrition advice. However, translation of the evidence linking polymorphisms, dietary requirements, and pathology risk proves to be challenging for nutrition and dietetic practitioners. Zinc status and polymorphisms of genes coding for zinc-transporters have been associated with chronic diseases. The present study aimed to systematically review the literature to assess whether recommendations for zinc intake could be made according to genotype. Eighteen studies investigating 31 Single Nucleotide Polymorphisms (SNPs) in relation to zinc intake and/or status were identified. Five studies examined type 2 diabetes; zinc intake was found to interact independently with two polymorphisms in the zinc-transporter gene SLC30A8 to affect glucose metabolism indicators. While the outcomes were statistically significant, the small size of the effect and lack of replication raises issues regarding translation into nutrition and dietetic practice. Two studies assessed the relationship of polymorphisms and cognitive performance; seven studies assessed the association between a range of outcomes linked to chronic conditions in aging population; two papers described the analysis of the genetic contribution in determining zinc concentration in human milk; and two papers assessed zinc concentration in plasma without linking to clinical outcomes. The data extracted confirmed a connection between genetics and zinc requirements, although the direction and magnitude of the dietary modification for carriers of specific genotypes could not be defined. This study highlights the need to summarise nutrigenetics studies to enable health professionals to translate scientific evidence into dietary recommendations.
Collapse
|
9
|
Kim H, Jung BM, Lee BN, Kim YJ, Jung JA, Chang N. Retinol, α-tocopherol, and selected minerals in breast milk of lactating women with full-term infants in South Korea. Nutr Res Pract 2017; 11:64-69. [PMID: 28194267 PMCID: PMC5300949 DOI: 10.4162/nrp.2017.11.1.64] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 11/17/2016] [Accepted: 11/22/2016] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND/OBJECTIVES This study was performed to measure fat-soluble vitamins and minerals in breast milk of Korean lactating mothers who exclusively breastfed their babies. SUBJECTS/METHODS Breast milk samples were collected from 334 mothers. Concentrations of retinol and α-tocopherol were analyzed by high performance liquid chromatography ultraviolet spectrometry while concentrations of minerals were measured by inductively coupled plasma optical emission spectrometry. RESULTS Retinol and α-tocopherol contents of breast milk were 39.58 ± 19.64 µg/dL and 0.23 ± 0.13 mg/dL, respectively. Average sodium, potassium, calcium, phosphorus, and magnesium levels in breast milk were 11.11 ± 5.16, 38.56 ± 9.01, 27.87 ± 6.10, 13.56 ± 3.30, and 3.05 ± 0.65 mg/dL, respectively. Contents of trace elements such as iron, zinc, copper, and manganese were 40.26 ± 46.21, 98.40 ± 62.47, 24.09 ± 9.03, and 0.90 ± 1.63 µg/dL, respectively. Fat-soluble vitamin concentration was positively correlated with total fat in milk samples, but no significant differences were observed in levels of retinol, α-tocopherol, or minerals based on whether or not lactating women were taking dietary supplements. CONCLUSIONS Micronutrient contents of breast milk samples from Korean lactating women were comparable to those of other nations. Retinol and α-tocopherol levels were correlated and also with total fat in breast milk.
Collapse
Affiliation(s)
- Hyesook Kim
- Department of Nutritional Science and Food Management, Ewha Womans University, 52, Ewhayeodae-gil, Seodaemun-gu, Seoul 03760, Korea
| | - Byung-Mun Jung
- Maeil Asia Human Milk Research Center, Maeil Dairies Co., Ltd, 50, Jongno-1-gil, Jongno-Gu, Seoul 03142, Korea
| | - Bum-Noh Lee
- Maeil Asia Human Milk Research Center, Maeil Dairies Co., Ltd, 50, Jongno-1-gil, Jongno-Gu, Seoul 03142, Korea
| | - Yun-Je Kim
- Maeil Asia Human Milk Research Center, Maeil Dairies Co., Ltd, 50, Jongno-1-gil, Jongno-Gu, Seoul 03142, Korea
| | - Ji A Jung
- Maeil Asia Human Milk Research Center, Maeil Dairies Co., Ltd, 50, Jongno-1-gil, Jongno-Gu, Seoul 03142, Korea
| | - Namsoo Chang
- Department of Nutritional Science and Food Management, Ewha Womans University, 52, Ewhayeodae-gil, Seodaemun-gu, Seoul 03760, Korea
| |
Collapse
|
10
|
Qian L, Zhao A, Zhang Y, Chen T, Zeisel SH, Jia W, Cai W. Metabolomic Approaches to Explore Chemical Diversity of Human Breast-Milk, Formula Milk and Bovine Milk. Int J Mol Sci 2016; 17:ijms17122128. [PMID: 27999311 PMCID: PMC5187928 DOI: 10.3390/ijms17122128] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 11/28/2016] [Accepted: 12/11/2016] [Indexed: 02/02/2023] Open
Abstract
Although many studies have been conducted on the components present in human breast milk (HM), research on the differences of chemical metabolites between HM, bovine milk (BM) and formula milk (FM) is limited. This study was to explore the chemical diversity of HM, BM and FM by metabolomic approaches. GC-TOFMS and UPLC-QTOFMS were applied to investigate the metabolic compositions in 30 HM samples, 20 FM samples and 20 BM samples. Metabolite profiling identified that most of the non-esterified fatty acids, which reflected the hydrolysis of triglycerides, were much more abundant in HM than those in FM and BM, except for palmitic acid and stearic acid. The levels of tricarboxylic acid (TCA) intermediates were much higher in FM and BM than those in HM. Each type of milk also showed its unique composition of free amino acids and free carbohydrates. In conclusion, higher levels of non-esterified saturated fatty acids with aliphatic tails <16 carbons, monounsaturated fatty acids and polyunsaturated fatty acids and lower levels of TCA intermediates are characteristic of HM, as compared with FM and BM. The content of non-esterified fatty acids may reflect the hydrolysis of triglycerides in different milk types.
Collapse
Affiliation(s)
- Linxi Qian
- Shanghai Institute for Pediatric Research, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 1665 Kongjiang Road, Shanghai 200092, China.
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 1665 Kongjiang Road, Shanghai 200092, China.
| | - Aihua Zhao
- Center for Translational Medicine, Six People's Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233, China.
| | - Yinan Zhang
- Center for Translational Medicine, Six People's Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233, China.
| | - Tianlu Chen
- Center for Translational Medicine, Six People's Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233, China.
| | - Steven H Zeisel
- Nutrition Research Institute, University of North Carolina, Chapel Hill, Kannapolis, NC 28081, USA.
| | - Wei Jia
- Center for Translational Medicine, Six People's Hospital, Shanghai Jiao Tong University, 600 Yishan Road, Shanghai 200233, China.
| | - Wei Cai
- Shanghai Institute for Pediatric Research, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 1665 Kongjiang Road, Shanghai 200092, China.
- Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, 1665 Kongjiang Road, Shanghai 200092, China.
| |
Collapse
|
11
|
Ackland ML, Michalczyk AA. Zinc and infant nutrition. Arch Biochem Biophys 2016; 611:51-57. [PMID: 27317042 DOI: 10.1016/j.abb.2016.06.011] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 05/23/2016] [Accepted: 06/13/2016] [Indexed: 01/12/2023]
Abstract
Zinc is essential for a wide variety of cellular processes in all cells. It is a critical dietary nutrient, particularly in the early stages of life. In the early neonatal period, adequate sources of zinc can be obtained from breast milk. In rare circumstances, the mammary gland produces zinc deficient milk that is potentially lethal for exclusively breast-fed infants. This can be overcome by zinc supplementation to the infant. Alterations to key zinc transporters provide insights into the mechanisms of cellular zinc homeostasis. The bioavailability of zinc in food depends on the presence of constituents that may complex zinc. In many countries, zinc deficiency is a major health issue due to poor nourishment. Young children are particularly affected. Zinc deficiency can impair immune function and contributes to the global burden of infectious diseases including diarrhoea, pneumonia and malaria. Furthermore, zinc deficiency may extend its influence across generations by inducing epigenetic effects that alter the expression of genes. This review discusses the significance of adequate zinc nutrition in infants, factors that influence zinc nutrition, the consequences of zinc deficiency, including its contribution to the global burden of disease, and addresses some of the knowledge gaps in zinc biology.
Collapse
Affiliation(s)
- M Leigh Ackland
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria 3125, Australia.
| | - Agnes A Michalczyk
- Centre for Cellular and Molecular Biology, School of Life and Environmental Sciences, Deakin University, Burwood, Victoria 3125, Australia
| |
Collapse
|
12
|
Kasana S, Din J, Maret W. Genetic causes and gene–nutrient interactions in mammalian zinc deficiencies: acrodermatitis enteropathica and transient neonatal zinc deficiency as examples. J Trace Elem Med Biol 2015; 29:47-62. [PMID: 25468189 DOI: 10.1016/j.jtemb.2014.10.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 10/14/2014] [Accepted: 10/16/2014] [Indexed: 12/31/2022]
Abstract
Discovering genetic causes of zinc deficiency has been a remarkable scientific journey. It started with the description of a rare skin disease, its treatment with various agents, the successful therapy with zinc, and the identification of mutations in a zinc transporter causing the disease. The journey continues with defining the molecular and cellular pathways that lead to the symptoms caused by zinc deficiency. Remarkably, at least two zinc transporters from separate protein families are now known to be involved in the genetics of zinc deficiency. One is ZIP4, which is involved in intestinal zinc uptake. Its mutations can cause acrodermatitis enteropathica (AE) with autosomal recessive inheritance. The other one is ZnT2, the transporter responsible for supplying human milk with zinc. Mutations in this transporter cause transient neonatal zinc deficiency (TNZD) with symptoms similar to AE but with autosomal dominant inheritance. The two diseases can be distinguished in affected infants. AE is fatal if zinc is not supplied to the infant after weaning, whereas TNZD is a genetic defect of the mother limiting the supply of zinc in the milk, and therefore the infant usually will obtain enough zinc once weaned. Although these diseases are relatively rare, the full functional consequences of the numerous mutations in ZIP4 and ZnT2 and their interactions with dietary zinc are not known. In particular, it remains unexplored whether some mutations cause milder disease phenotypes or increase the risk for other diseases if dietary zinc requirements are not met or exceeded. Thus, it is not known whether widespread zinc deficiency in human populations is based primarily on a nutritional deficiency or determined by genetic factors as well. This consideration becomes even more significant with regard to mutations in the other 22 human zinc transporters, where associations with a range of diseases, including diabetes, heart disease, and mental illnesses have been observed. Therefore, clinical tests for genetic disorders of zinc metabolism need to be developed.
Collapse
|
13
|
Kambe T, Hashimoto A, Fujimoto S. Current understanding of ZIP and ZnT zinc transporters in human health and diseases. Cell Mol Life Sci 2014; 71:3281-95. [PMID: 24710731 PMCID: PMC11113243 DOI: 10.1007/s00018-014-1617-0] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 03/13/2014] [Accepted: 03/20/2014] [Indexed: 12/14/2022]
Abstract
Zinc transporters, the Zrt-, Irt-like protein (ZIP) family and the Zn transporter (ZnT) family transporters, are found in all aspects of life. Increasing evidence has clarified the molecular mechanism, in which both transporters play critical roles in cellular and physiological functions via mobilizing zinc across the cellular membrane. In the last decade, mutations in ZIP and ZnT transporter genes have been shown to be implicated in a number of inherited human diseases. Moreover, dysregulation of expression and activity of both transporters has been suggested to be involved in the pathogenesis and progression of chronic diseases including cancer, immunological impairment, and neurodegenerative diseases, although comprehensive understanding is far from complete. The diverse phenotypes of diseases related to ZIP and ZnT transporters reflect the multifarious biological functions of both transporters. The present review summarizes the current understanding of ZIP and ZnT transporter functions from the standpoint of human health and diseases. The study of zinc transporters is currently of great clinical interest.
Collapse
Affiliation(s)
- Taiho Kambe
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, 606-8502, Japan,
| | | | | |
Collapse
|
14
|
Feng XL, Wang Y, An L, Ronsmans C. Cesarean section in the People's Republic of China: current perspectives. Int J Womens Health 2014; 6:59-74. [PMID: 24470775 PMCID: PMC3891566 DOI: 10.2147/ijwh.s41410] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
OBJECTIVE To review the current knowledge on the prevalence, reasons, and consequences of cesarean sections in the People's Republic of China. METHODS Peer-reviewed articles were systematically searched on PubMed. The following Chinese databases were comprehensively searched: the China National Knowledge Infrastructure, Wanfang, and the VIP information. The databases were searched from inception to September 1, 2013. Two reviewers independently screened the titles and abstracts for eligibility. Full texts of eligible papers were reviewed, where relevant references were hand-searched and reviewed. FINDINGS Sixty articles were included from PubMed, 17 articles were intentionally picked out from Chinese journals, and five additional articles were added, for a total of 82 articles for the analysis. With a current national rate near 40%, the literature consistently reported a rapid rise of cesarean sections in the People's Republic of China in the past decades, irrespective of where people lived or their socioeconomic standing. Nonclinical factors were considered as the main drivers fueling the rise of cesareans in the People's Republic of China. There was a lively debate on whether women's preferences or providers' distorted financial incentives affected the rise in cesarean sections. However, recent evidence suggests that it might be the People's Republic of China's health development approach - focusing on specialized care and marginalizing primary care - that is playing a role. Although 30 articles were identified studying the consequences of cesareans, the methodologies are in general weak and the themes are out of focus. CONCLUSION The overuse of cesareans is rising alarmingly in the People's Republic of China and has become a real public health problem. No consensus has been made on the leverage factors that drive the cesarean epidemic, particularly for those nonclinical factors. The more macro level structural factors may have played a part, though further research is warranted to understand the mechanisms. Knowledge of the consequences of cesareans, particularly for women, is limited in the People's Republic of China, leaving a substantial literature gap.
Collapse
Affiliation(s)
- Xing Lin Feng
- Department of Health Policy and Administration, School of Public Health, Peking University, Beijing, People's Republic of China
| | - Ying Wang
- Department of Health Policy and Administration, School of Public Health, Peking University, Beijing, People's Republic of China
| | - Lin An
- Department of Women, Children and Adolescent Health, School of Public Health, Peking University, Beijing, People's Republic of China
| | - Carine Ronsmans
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, England
| |
Collapse
|
15
|
Itsumura N, Inamo Y, Okazaki F, Teranishi F, Narita H, Kambe T, Kodama H. Compound heterozygous mutations in SLC30A2/ZnT2 results in low milk zinc concentrations: a novel mechanism for zinc deficiency in a breast-fed infant. PLoS One 2013; 8:e64045. [PMID: 23741301 PMCID: PMC3669329 DOI: 10.1371/journal.pone.0064045] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 04/05/2013] [Indexed: 12/16/2022] Open
Abstract
Zinc concentrations in breast milk are considerably higher than those of the maternal serum, to meet the infant's requirements for normal growth and development. Thus, effective mechanisms ensuring secretion of large amounts of zinc into the milk operate in mammary epithelial cells during lactation. ZnT2 was recently found to play an essential role in the secretion of zinc into milk. Heterozygous mutations of human ZnT2 (hZnT2), including H54R and G87R, in mothers result in low (>75% reduction) secretion of zinc into the breast milk, and infants fed on the milk develop transient neonatal zinc deficiency. We identified two novel missense mutations in the SLC30A2/ZnT2 gene in a Japanese mother with low milk zinc concentrations (>90% reduction) whose infant developed severe zinc deficiency; a T to C transition (c.454T>C) at exon 4, which substitutes a tryptophan residue with an arginine residue (W152R), and a C to T transition (c.887C>T) at exon 7, which substitutes a serine residue with a leucine residue (S296L). Biochemical characterization using zinc-sensitive DT40 cells indicated that the W152R mutation abolished the abilities to transport zinc and to form a dimer complex, indicating a loss-of-function mutation. The S296L mutation retained both abilities but was extremely destabilized. The two mutations were found on different alleles, indicating that the genotype of the mother with low milk zinc was compound heterozygous. These results show novel compound heterozygous mutations in the SLC30A2/ZnT2 gene causing zinc deficiency in a breast-fed infant.
Collapse
Affiliation(s)
- Naoya Itsumura
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Yasuji Inamo
- Department of Pediatrics and Child Health, Nihon University School of Medicine, Tokyo, Japan
| | - Fumiko Okazaki
- Department of Food Science, Kyoto Women's University, Kyoto, Japan
| | - Fumie Teranishi
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Hiroshi Narita
- Department of Food Science, Kyoto Women's University, Kyoto, Japan
| | - Taiho Kambe
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Hiroko Kodama
- Department of Pediatrics, Teikyo University School of Medicine, Tokyo, Japan
- Department of Health and Dietetics, Faculty of Health and Medical Sciences, Teikyo Heisei University, Tokyo, Japan
| |
Collapse
|
16
|
Krebs NF. Update on Zinc Deficiency and Excess in Clinical Pediatric Practice. ANNALS OF NUTRITION AND METABOLISM 2013; 62 Suppl 1:19-29. [DOI: 10.1159/000348261] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
17
|
Neville MC, Anderson SM, McManaman JL, Badger TM, Bunik M, Contractor N, Crume T, Dabelea D, Donovan SM, Forman N, Frank DN, Friedman JE, German JB, Goldman A, Hadsell D, Hambidge M, Hinde K, Horseman ND, Hovey RC, Janoff E, Krebs NF, Lebrilla CB, Lemay DG, MacLean PS, Meier P, Morrow AL, Neu J, Nommsen-Rivers LA, Raiten DJ, Rijnkels M, Seewaldt V, Shur BD, VanHouten J, Williamson P. Lactation and neonatal nutrition: defining and refining the critical questions. J Mammary Gland Biol Neoplasia 2012; 17:167-88. [PMID: 22752723 PMCID: PMC3428522 DOI: 10.1007/s10911-012-9261-5] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 06/06/2012] [Indexed: 01/15/2023] Open
Abstract
This paper resulted from a conference entitled "Lactation and Milk: Defining and refining the critical questions" held at the University of Colorado School of Medicine from January 18-20, 2012. The mission of the conference was to identify unresolved questions and set future goals for research into human milk composition, mammary development and lactation. We first outline the unanswered questions regarding the composition of human milk (Section I) and the mechanisms by which milk components affect neonatal development, growth and health and recommend models for future research. Emerging questions about how milk components affect cognitive development and behavioral phenotype of the offspring are presented in Section II. In Section III we outline the important unanswered questions about regulation of mammary gland development, the heritability of defects, the effects of maternal nutrition, disease, metabolic status, and therapeutic drugs upon the subsequent lactation. Questions surrounding breastfeeding practice are also highlighted. In Section IV we describe the specific nutritional challenges faced by three different populations, namely preterm infants, infants born to obese mothers who may or may not have gestational diabetes, and infants born to undernourished mothers. The recognition that multidisciplinary training is critical to advancing the field led us to formulate specific training recommendations in Section V. Our recommendations for research emphasis are summarized in Section VI. In sum, we present a roadmap for multidisciplinary research into all aspects of human lactation, milk and its role in infant nutrition for the next decade and beyond.
Collapse
|