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Nutrients Jun 2021Numerous studies indicate that zinc and the new zinc-related adipokine, zinc-α2-glycoprotein (ZAG), are involved in lipid metabolism. Excess body fat lowers blood... (Review)
Review
Numerous studies indicate that zinc and the new zinc-related adipokine, zinc-α2-glycoprotein (ZAG), are involved in lipid metabolism. Excess body fat lowers blood concentrations of Zn and ZAG, leading not only to the development of obesity but also to other components of the metabolic syndrome. Zinc homeostasis disorders in the body negatively affect the lipid profile and cytokine secretion. Zinc appears to be a very important ZAG homeostasis regulator. The physiological effects of ZAG are related to lipid metabolism, but studies show that ZAG also affects glucose metabolism and is linked to insulin resistance. ZAG has a zinc binding site in its structure, which may indicate that ZAG mediates the effect of zinc on lipid metabolism. The review aimed to verify the available studies on the effects of zinc and ZAG on lipid metabolism. A literature review within the scope of this research area was conducted using articles available in PubMed (including MEDLINE), Web of Science and Cochrane Library databases. An analysis of available studies has shown that zinc improves hepatic lipid metabolism and has an impact on the lipid profile. Numerous studies have found that zinc supplementation in overweight individuals significantly reduced blood levels of total cholesterol, LDL (Low-density lipoprotein)cholesterol and triglycerides, potentially reducing cardiovascular morbidity and mortality. Some results also indicate that it increases HDL-C (High-density lipoprotein) cholesterol levels. ZAG has been shown to play a significant role in reducing obesity and improving insulin sensitivity, both in experimental animal model studies and in human studies. Furthermore, ZAG at physiologically relevant concentrations increases the release of adiponectin from human adipocytes. In addition, ZAG has been shown to inhibit in vitro leptin production. Further studies are needed to provide more data on the role of zinc and zinc-α2-glycoprotein.
Topics: Adipokines; Adipose Tissue; Animals; Body Weight; Female; Humans; Lipid Metabolism; Lipids; Liver; Male; Overweight; Seminal Plasma Proteins; Zinc; Zn-Alpha-2-Glycoprotein
PubMed: 34208404
DOI: 10.3390/nu13062023 -
Pancreatology : Official Journal of the... Oct 2020Zinc is an essential trace element. Deficiencies are frequently seen with gastrointestinal diseases, including chronic pancreatitis, nutritional deficiency, and reduced... (Review)
Review
Zinc is an essential trace element. Deficiencies are frequently seen with gastrointestinal diseases, including chronic pancreatitis, nutritional deficiency, and reduced intestinal absorption. Additionally, reduced zinc levels have been linked to cellular changes associated with acute pancreatitis such as enhanced inflammation with increased macrophage activation and production of inflammatory cytokines such as IL-1β, impaired autophagy, and modulation of calcium homeostasis. Preliminary data suggest that zinc deficiency may lead to pancreatic injury in animal models. The purpose of this review is to explore the biologic effects of zinc deficiency that could impact pancreatic disease. MESH KEYWORDS: Malnutrition, inflammation, trace element.
Topics: Animals; Humans; Inflammation; Pancreas; Pancreatic Diseases; Zinc
PubMed: 32917512
DOI: 10.1016/j.pan.2020.08.016 -
International Journal of Molecular... Nov 2017While zinc is known to be important for many biological processes in animals at a molecular and physiological level, new evidence indicates that it may also be involved... (Review)
Review
While zinc is known to be important for many biological processes in animals at a molecular and physiological level, new evidence indicates that it may also be involved in the regulation of sleep. Recent research has concluded that zinc serum concentration varies with the amount of sleep, while orally administered zinc increases the amount and the quality of sleep in mice and humans. In this review, we provide an exhaustive study of the literature connecting zinc and sleep, and try to evaluate which molecular mechanism is likely to be involved in this phenomenon. A better understanding should provide critical information not only about the way zinc is related to sleep but also about how sleep itself works and what its real function is.
Topics: Animals; Dietary Supplements; Humans; Sleep; Sleep Aids, Pharmaceutical; Zinc
PubMed: 29113075
DOI: 10.3390/ijms18112334 -
The Cochrane Database of Systematic... Nov 2016Tinnitus is the perception of sound without external acoustic stimuli. Patients with severe tinnitus may have physical and psychological complaints and their tinnitus... (Review)
Review
BACKGROUND
Tinnitus is the perception of sound without external acoustic stimuli. Patients with severe tinnitus may have physical and psychological complaints and their tinnitus can cause deterioration in their quality of life. At present no specific therapy for tinnitus has been found to be satisfactory in all patients. In recent decades, a number of reports have suggested that oral zinc supplementation may be effective in the management of tinnitus. Since zinc has a role in cochlear physiology and in the synapses of the auditory system, there is a plausible mechanism of action for this treatment.
OBJECTIVES
To evaluate the effectiveness and safety of oral zinc supplementation in the management of patients with tinnitus.
SEARCH METHODS
The Cochrane ENT Information Specialist searched the ENT Trials Register; Central Register of Controlled Trials (CENTRAL 2016, Issue 6); PubMed; EMBASE; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 14 July 2016.
SELECTION CRITERIA
Randomised controlled trials comparing zinc supplementation versus placebo in adults (18 years and over) with tinnitus.
DATA COLLECTION AND ANALYSIS
We used the standard methodological procedures recommended by Cochrane. Our primary outcome measures were improvement in tinnitus severity and disability, measured by a validated tinnitus-specific questionnaire, and adverse effects. Secondary outcomes were quality of life, change in socioeconomic impact associated with work, change in anxiety and depression disorders, change in psychoacoustic parameters, change in tinnitus loudness, change in overall severity of tinnitus and change in thresholds on pure tone audiometry. We used GRADE to assess the quality of the evidence for each outcome; this is indicated in italics.
MAIN RESULTS
We included three trials involving a total of 209 participants. The studies were at moderate to high risk of bias. All included studies had differences in participant selection criteria, length of follow-up and outcome measurement, precluding a meta-analysis. The participants were all adults over 18 years with subjective tinnitus, but one study conducted in 2013 (n = 109) included only elderly patients. Improvement in tinnitus severity and disabilityOnly the study in elderly patients used a validated instrument (Tinnitus Handicap Questionnaire) for this primary outcome. The authors of this cross-over study did not report the results of the two phases separately and found no significant differences in the proportion of patients reporting tinnitus improvement at four months of follow-up: 5% (5/93) versus 2% (2/94) in the zinc and placebo groups, respectively (risk ratio (RR) 2.53, 95% confidence interval (CI) 0.50 to 12.70; very low-quality evidence).None of the included studies reported any significant adverse effects. Secondary outcomesFor the secondary outcome change in tinnitus loudness, one study reported no significant difference between the zinc and placebo groups after eight weeks: mean difference in tinnitus loudness -9.71 dB (95% CI -25.53 to 6.11; very low-quality evidence). Another study also measured tinnitus loudness but used a 0- to 100-point scale. The authors of this second study reported no significant difference between the zinc and placebo groups after four months: mean difference in tinnitus loudness rating scores 0.50 (95% CI -5.08 to 6.08; very low-quality evidence).Two studies used unvalidated instruments to assess tinnitus severity. One (with 50 participants) reported the severity of tinnitus using a non-validated scale (0 to 7 points) and found no significant difference in subjective tinnitus scores between the zinc and placebo groups at the end of eight weeks of follow-up (mean difference (MD) -1.41, 95% CI -2.97 to 0.15; very low-quality evidence). A third trial (n = 50) also evaluated the improvement of tinnitus using a non-validated instrument (a 0 to 10 scale: 10 = severe and unbearable tinnitus). In this study, after eight weeks there was no difference in the proportion of patients with improvement in their tinnitus, 8.7% (2/23) treated with zinc versus 8% (2/25) of those who received a placebo (RR 1.09, 95% CI 0.17 to 7.10, very low-quality evidence).None of the included studies reported any of our other secondary outcomes (quality of life, change in socioeconomic impact associated with work, change in anxiety and depression disorders, change in psychoacoustic parameters or change in thresholds on pure tone audiometry).
AUTHORS' CONCLUSIONS
We found no evidence that the use of oral zinc supplementation improves symptoms in adults with tinnitus.
Topics: Administration, Oral; Adult; Aged; Humans; Middle Aged; Randomized Controlled Trials as Topic; Surveys and Questionnaires; Tinnitus; Treatment Outcome; Zinc
PubMed: 27879981
DOI: 10.1002/14651858.CD009832.pub2 -
Nutrients Jun 2015Zinc supplementation has been shown to reduce the incidence and prevalence of diarrhea; however, its anti-diarrheal effect remains only partially understood. There is... (Review)
Review
Zinc supplementation has been shown to reduce the incidence and prevalence of diarrhea; however, its anti-diarrheal effect remains only partially understood. There is now growing evidence that zinc can have pathogen-specific protective effects. Giardiasis is a common yet neglected cause of acute-chronic diarrheal illness worldwide which causes disturbances in zinc metabolism of infected children, representing a risk factor for zinc deficiency. How zinc metabolism is compromised by Giardia is not well understood; zinc status could be altered by intestinal malabsorption, organ redistribution or host-pathogen competition. The potential metal-binding properties of Giardia suggest unusual ways that the parasite may interact with its host. Zinc supplementation was recently found to reduce the rate of diarrhea caused by Giardia in children and to upregulate humoral immune response in Giardia-infected mice; in vitro and in vivo, zinc-salts enhanced the activity of bacitracin in a zinc-dose-dependent way, and this was not due to zinc toxicity. These findings reflect biological effect of zinc that may impact significantly public health in endemic areas of infection. In this paper, we shall explore one direction of this complex interaction, discussing recent information regarding zinc status and its possible contribution to the outcome of the encounter between the host and Giardia.
Topics: Animals; Diarrhea; Dietary Supplements; Disease Models, Animal; Dose-Response Relationship, Drug; Giardia lamblia; Giardiasis; Humans; Immunity, Humoral; Intestines; Zinc
PubMed: 26046395
DOI: 10.3390/nu7064438 -
Yakugaku Zasshi : Journal of the... Mar 2008Zinc is an essential trace element and serves as the active center of approximately 300 enzymes. Therefore, zinc deficiency may be associated with a variety of clinical... (Review)
Review
Zinc is an essential trace element and serves as the active center of approximately 300 enzymes. Therefore, zinc deficiency may be associated with a variety of clinical features such as hypogeusia, hyposmia, growth retardation, dermatitis, alopecia, gonadal hypofunction, abnormal pregnancy, susceptibility to infections, delayed wound healing, impaired glucose tolerance, and increased carcinogenesis. Zinc deficiency was reported to be on the increase in the Nagano Study conducted from 2003 to 2005. Zinc therapy is classified into two categories, zinc-supplementary and -specific treatments. Ordinarily, zinc-supplementary therapy is carried out for the symptoms and diseases caused by zinc deficiency. On the other hand, zinc-specific therapy is applied to obtain copper- and iron-chelating, antifibrotic, and antidiabetic effects. The availability of zinc-specific therapy is now confirmed in humans and animals. Hereafter, the safety of zinc therapy needs to be examined further.
Topics: Animals; Collagen; Copper; Female; Fibrosis; Humans; Hypoglycemic Agents; Intestinal Absorption; Intestine, Small; Iron; Male; Pregnancy; Validation Studies as Topic; Zinc
PubMed: 18311051
DOI: 10.1248/yakushi.128.333 -
Biometals : An International Journal on... Feb 2021To determine the effects of repeated physical activity on iron and zinc homeostases in a living system, we quantified blood and tissue levels of these two metals in...
To determine the effects of repeated physical activity on iron and zinc homeostases in a living system, we quantified blood and tissue levels of these two metals in sedentary and physically active Long-Evans rats. At post-natal day (PND) 22, female rats were assigned to either a sedentary or an active treatment group (n = 10/group). The physically active rats increased their use of a commercially-constructed stainless steel wire wheel so that, by the end of the study (PND 101), they were running an average of 512.8 ± 31.9 (mean ± standard error) min/night. After euthanization, plasma and aliquots of liver, lung, heart, and gastrocnemius muscle were obtained. Following digestion, non-heme iron and zinc concentrations in plasma and tissues were measured using inductively coupled plasma optical emission spectroscopy. Concentrations of both non-heme iron and zinc in plasma and liver were significantly decreased among the physically active rats relative to the sedentary animals. In the lung, both metals were increased in concentration among the physically active animals but the change in zinc did not reach significance. Similarly, tissue non-heme iron and zinc levels were both increased in heart and muscle from the physically active group. It is concluded that repeated physical activity in an animal model can be associated with a translocation of both iron and zinc from sites of storage (e.g. liver) to tissues with increased metabolism (e.g. the lung, heart, and skeletal muscle).
Topics: Animals; Female; Homeostasis; Iron; Physical Conditioning, Animal; Rats; Rats, Long-Evans; Sedentary Behavior; Zinc
PubMed: 33237470
DOI: 10.1007/s10534-020-00266-w -
International Journal of Molecular... Jan 2020Prostate cancer (PCa) is one of the most common cancers and the second leading cause of cancer-related death among men worldwide. Despite progresses in early diagnosis... (Review)
Review
Prostate cancer (PCa) is one of the most common cancers and the second leading cause of cancer-related death among men worldwide. Despite progresses in early diagnosis and therapeutic strategies, prognosis for patients with advanced PCa remains poor. Noteworthily, a unique feature of healthy prostate is its highest level of zinc content among all soft tissues in the human body, which dramatically decreases during prostate tumorigenesis. To date, several reviews have suggested antitumor activities of zinc and its potential as a therapeutic strategy of PCa. However, an overview about the role of zinc and its signaling in PCa is needed. Here, we review literature related to the content, biological function, compounds and clinical application of zinc in PCa. We first summarize zinc content in prostate tissue and sera of PCa patients with their clinical relevance. We then elaborate biological functions of zinc signaling in PCa on three main aspects, including cell proliferation, death and tumor metastasis. Finally, we discuss clinical applications of zinc-containing compounds and proteins involved in PCa signaling pathways. Based on currently available studies, we conclude that zinc plays a tumor suppressive role and can serve as a biomarker in PCa diagnosis and therapies.
Topics: Cell Proliferation; Disease Progression; Gene Expression Regulation, Neoplastic; Gene Regulatory Networks; Humans; Male; Neoplasm Metastasis; Prognosis; Prostatic Neoplasms; Signal Transduction; Zinc
PubMed: 31963946
DOI: 10.3390/ijms21020667 -
Boletin Medico Del Hospital Infantil de... 2017Acrodermatitis enteropathica is a low-incidence disease due to inherited or acquired zinc deficiency. It is characterized by acral dermatitis, alopecia, diarrhea and...
INTRODUCTION
Acrodermatitis enteropathica is a low-incidence disease due to inherited or acquired zinc deficiency. It is characterized by acral dermatitis, alopecia, diarrhea and growth retardation. The dermatological condition may mimic a cutaneous fungal infection or other pathogen-related skin diseases.
CASE REPORT
We report the case of a female patient of 7 months of age, who was sent to Centro Médico Nacional 20 de Noviembre for suspicion of immunodeficiency and cutaneous mycosis. Her condition began with dermatosis disseminated to the head, trunk and genital region; initial treatment with antifungal and broad spectrum antibiotics was given, without improvement. Upon admission, immunodeficiency and fungal infection were discarded. Acrodermatitis enteropathica was suspected, and corroborated later by low serum zinc levels. Immediately after the start of oral treatment with zinc, the patient showed improvement.
CONCLUSIONS
There are multiple differential diagnoses of acrodermatitis enteropathica, which includes cutaneous infections. Therefore, the early recognition of the characteristic lesions favors suspicion, diagnosis and appropriate treatment.
Topics: Acrodermatitis; Administration, Oral; Diagnosis, Differential; Female; Humans; Infant; Skin Diseases; Zinc
PubMed: 29382519
DOI: 10.1016/j.bmhimx.2017.05.002 -
International Immunopharmacology Jul 2021The novel SARS-CoV-2 which was first reported in China is the cause of infection known as COVID-19. In comparison with other coronaviruses such as SARS-CoV and MERS, the... (Review)
Review
The novel SARS-CoV-2 which was first reported in China is the cause of infection known as COVID-19. In comparison with other coronaviruses such as SARS-CoV and MERS, the mortality rate of SARS-CoV-2 is lower but the transmissibility is higher. Immune dysregulation is the most common feature of the immunopathogenesis of COVID-19 that leads to hyperinflammation. Micronutrients such as zinc are essential for normal immune function. According to the assessment of WHO, approximately one-third of the world's society suffer from zinc deficiency. Low plasma levels of zinc are associated with abnormal immune system functions such as impaired chemotaxis of polymorphonuclear cells (PMNs) and phagocytosis, dysregulated intracellular killing, overexpression of the inflammatory cytokines, lymphopenia, decreased antibody production, and sensitivity to microbes especially viral respiratory infections. Zinc exerts numerous direct and indirect effects against a wide variety of viral species particularly RNA viruses. The use of zinc and a combination of zinc-pyrithione at low concentrations impede SARS-CoV replication in vitro. Accordingly, zinc can inhibit the elongation step of RNA transcription. Furthermore, zinc might improve antiviral immunity by up-regulation of IFNα through JAK/STAT1 signaling pathway in leukocytes. On the other hand, zinc supplementation might ameliorate tissue damage caused by mechanical ventilation in critical COVID-19 patients. Finally, zinc might be used in combination with antiviral medications for the management of COVID-19 patients. In the current review article, we review and discuss the immunobiological roles and antiviral properties as well as the therapeutic application of zinc in SARS-CoV-2 and related coronaviruses infections.
Topics: COVID-19; Humans; SARS-CoV-2; Virus Replication; Zinc
PubMed: 33882442
DOI: 10.1016/j.intimp.2021.107630