Antioxidant and anti-inflammatory effects of zinc. Zinc-dependent NF-κB signaling

Micronutrients as immunomodulatory tools for COVID-19 management

COVID-19 rapidly turned to a global pandemic posing lethal threats to overwhelming health care capabilities, despite its relatively low mortality rate. The clinical respiratory symptoms include dry cough, fever, anosmia, breathing difficulties, and subsequent respiratory failure. No known cure is available for COVID-19. Apart from the anti-viral strategy, the supports of immune effectors and modulation of immunosuppressive mechanisms is the rationale immunomodulation approach in COVID-19 management. Diet and nutrition are essential for healthy immunity. However, a group of micronutrients plays a dominant role in immunomodulation. The deficiency of most nutrients increases the individual susceptibility to virus infection with a tendency for severe clinical presentation. Despite a shred of evidence, the supplementation of a single nutrient is not promising in the general population. Individuals at high-risk for specific nutrient deficiencies likely benefit from supplementation. The individual dietary and nutritional status assessments are critical for determining the comprehensive actions in COVID-19.

Delineating colorectal cancer distribution, interaction, and risk prediction by environmental risk factors and serum trace elements

The burden of colorectal cancer (CRC) is increasing worldwide especially in developing countries. This phenomenon may be attributable to lifestyle, dietary and environmental risk factors. We aimed to determine the level of 25 trace elements, their interaction with environmental risk factors, and subsequently develop a risk prediction model for CRC (RPM CRC). For the discovery phase, we used a hospital-based case-control study (CRC and non-CRC patients) and in the validation phase we analysed pre-symptomatic samples of CRC patients from The Malaysian Cohort Biobank. Information on the environmental risk factors were obtained and level of 25 trace elements measured using the ICP-MS method. CRC patients had lower Zn and Se levels but higher Li, Be, Al, Co, Cu, As, Cd, Rb, Ba, Hg, Tl, and Pb levels compared to non-CRC patients. The positive interaction between red meat intake ≥ 50 g/day and Co ≥ 4.77 µg/L (AP 0.97; 95% CI 0.91, 1.03) doubled the risk of CRC. A panel of 24 trace elements can predict simultaneously and accurate of high, moderate, and low risk of CRC (accuracy 100%, AUC 1.00). This study provides a new input on possible roles for various trace elements in CRC as well as using a panel of trace elements as a screening approach to CRC.

Zinc Protects against MDMA-Induced Apoptosis of Sertoli Cells in Mouse via Attenuation of Caspase-3

Background

3,4-Methylenedioxymethamphetamine (MDMA) disrupts function of the endocrine system and different organs such as heart, blood vessels, kidney, liver and nervous systems. This revision was conducted to evaluate impact of MDMA on apoptosis and Zinc in the MDMA-induced apoptosis of cultured Sertoli cells by measuring Caspase-3 gene expression.

Materials and Methods

In this experimental study, Sertoli cells were incubated with MDMA (0, 0.5, 1, 3 and 5 mM), Zinc (0, 8, 16, 32, 64 μM) and Zinc (8 μM) prior to adding MDMA (5 mM) for 24 and 48 hours. MTT assay was used for evaluating impacts of these conditions on the viability of Sertoli cells. Caspase-3 gene expression level was detected using quantitative reverse transcription PCR (qRT-PCR) in all of the tested groups.

Results

Finding showed that cellular viability was decreased and level of Caspase-3 mRNA was increased in MDMA treated cells. Additionally, pre-treatment with Zinc (8 μM) attenuated MDMA-induced apoptosis and down-regulated caspase-3. The mean of caspase-3 mRNA level (fold change ± SE) was 3.98 ± 1.18, 0.31 ± 0.28, and 1.72 ± 0.28 in respectively MDMA (5 mM), Zinc (8 μM), and Zinc+MDMA groups vs. control group. The mean of Caspase-3 mRNA (fold change) was not statistically different in the tested groups (P>0.05), unless MDMA (5 mM) group (P=0.008).

Conclusion

We suggest that MDMA toxicity could be involved in apoptosis of Sertoli cells. In addition, Zinc could reduce MDMA-induced apoptosis by down-regulation of Caspase-3 mRNA levels.

Forgotten partners and function regulators of inducible metallothioneins

Metallothioneins are peculiar cysteine rich, heat resistant, small cellular plasma proteins expressed through almost all life forms. The currently established biological functions of metallothioneins are the homeostasis of essential metals and protection against toxic transitional metals (TM) alongside defence from oxidative stress by direct scavenging of reactive oxygen and nitrogen species (ROS and RNS). In mammals, among the four main evolutionary conserved forms, only the ubiquitously expressed metallothionein 1 and 2 (here abbreviated as MT) are inducible by TM, oxidative stress, glucocorticoids and starvation among various other stimuli. However, more than sixty years after being discovered, metallothioneins still bear unresolved issues about their possible physiological function and regulation. The biological function of MTs has still not been associated with the in vitro-demonstrated capacity of MT interaction with cellular molecules glutathione (GSH) or adenosine triphosphate (ATP), or with the possibility of direct iron-MT binding in the reducing intracellular environment of some organelles, e.g. lysosomes. Iron as the most abundant cellular TM is also one of the main physiological sources of ROS. Moreover, iron exhibits strain, sex and age differences that reflected ROS generation and MT induction in (patho)physiology and toxicology studies. A recent study showed that iron sex differences follows expression of both ferritin and MT leading to wide implications from essential TM interconnectivity to aging. This review places emphasis on biochemically proven but physiologically ignored interactions of MT with iron to stimulate advanced research for establishing a wide frame of the biological roles of MTs important for health and longevity.

Micronutrients and bioactive compounds in the immunological pathways related to SARS-CoV-2 (adults and elderly)

The new coronavirus pandemic is affecting the entire world with more than 25 million confirmed cases in August 2020 according to the World Health Organization. It is known that the virus can affect several tissues and can progress to a respiratory failure in severe cases. To prevent the progression to this stage of the disease and minimize all the damage caused by coronavirus (SARS-CoV-2) the immune system must be in its integrity. A healthy nutritional status are fundamental to efficient immunological protection and consequently a good response to SARS-CoV-2. Micronutrients and bioactive compounds perform functions in immune cells that are extremely essential to stop SARS-CoV-2. Their adequate consumption is part of a non-pharmacological intervention to keep the immune system functioning. This review has as main objective to inform how micronutrients and bioactive compounds could act in the essential immunological pathways could stop SARS-CoV-2, focusing on the functions that have already established in the literature and transposing to this scenario.

A Multi-Omics Approach Identifies Key Regulatory Pathways Induced by Long-Term Zinc Supplementation in Human Primary Retinal Pigment Epithelium

In age-related macular degeneration (AMD), both systemic and local zinc levels decline. Elevation of zinc in clinical studies delayed the progression to end-stage AMD. However, the molecular pathways underpinning this beneficial effect are not yet identified. In this study, we used differentiated primary human fetal retinal pigment epithelium (RPE) cultures and long-term zinc supplementation to carry out a combined transcriptome, proteome and secretome analysis from three genetically different human donors. After combining significant differences, we identified the complex molecular networks using Database for Annotation, Visualization and Integrated Discovery (DAVID) and Ingenuity Pathway Analysis (IPA). The cell cultures from the three donors showed extensive pigmentation, development of microvilli and basal infoldings and responded to zinc supplementation with an increase in transepithelial electrical resistance (TEER) (apical supplementation: 443.2 ± 79.3%, basal supplementation: 424.9 ± 116.8%, compared to control: 317.5 ± 98.2%). Significant changes were observed in the expression of 1044 genes, 151 cellular proteins and 124 secreted proteins. Gene set enrichment analysis revealed changes in specific molecular pathways related to cell adhesion/polarity, extracellular matrix organization, protein processing/transport, and oxidative stress response by zinc and identified a key upstream regulator effect similar to that of TGFB1.

Zinc: Roles in pancreatic physiology and disease

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.

Mitochondrial TXN2 attenuates amyloidogenesis via selective inhibition of BACE1 expression

Thioredoxin-2 (TXN2) is a mitochondrial protein and represents one of the intrinsic antioxidant enzymes. It has long been recognized that mitochondrial dysfunction and oxidative stress contribute to the pathogenesis of Alzheimer's disease (AD). We hypothesized that mitochondrial TXN2 might play a role in AD-like pathology. In this study, we found that in SH-SY5Y and HEK cells stably express full-length human amyloid-β precursor protein (HEK-APP), TXN2 silencing or over-expression selectively increased or decreased the transcription of beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), respectively, without altering the protein levels of others enzymes involved in the catalytic processing of APP. As a result, β-amyloid protein (Aβ) levels were significantly decreased by TXN2. In addition, in cells treated with 3-nitropropionic acid (3-NP) that is known to increase reactive oxygen species (ROS) and promote mitochondrial dysfunction, TXN2 silencing resulted in further enhancement of BACE1 protein levels, suggesting a role of TXN2 in ROS removal. The downstream signaling might involve NFκB, as TXN2 reduced the phosphorylation of p65 and IκBα; and p65 knockdown significantly attenuated TXN2-mediated regulation of BACE1. Concomitantly, the levels of cellular ROS, apoptosis-related proteins and cell viability were altered by TXN2 silencing or over-expression. In APPswe/PS1E9 mice, an animal model of AD, the cortical and hippocampal TXN2 protein levels were decreased at 12 months but not at 6 months, suggesting an age-dependent decline. Collectively, TXN2 regulated BACE1 expression and amyloidogenesis via cellular ROS and NFκB signaling. TXN2 might serve as a potential target especially for early intervention of AD.

Zinc supplementation affects favorably the frequency of migraine attacks: a double-blind randomized placebo-controlled clinical trial

BACKGROUND

Observational studies have shown a link between zinc deficiency and migraine headaches. We aimed to examine the effect of zinc supplementation on the characteristics of migraine attacks in patients with migraine.

METHODS

This randomized clinical trial was conducted on 80 patients with migraine. Patients were randomly assigned to receive either zinc sulfate (220 mg/d zinc sulfate) or placebo (lactose) for 8 weeks. Anthropometric measures, serum zinc concentrations, and characteristics of migraine attacks (headache severity, frequency and duration of migraine attacks, and headache daily results) were assessed at baseline and end of the trial.

RESULTS

Compared with the placebo, zinc supplementation resulted in a significant reduction in headache severity (- 1.75 ± 1.79 vs. -0.80 ± 1.57; P = 0.01) and migraine attacks frequency (- 2.55 ± 4.32 vs. -0.42 ± 4.24; P = 0.02) in migraine patients. However, the observed reduction for headache severity became statistically non-significant when the analysis was adjusted for potential confounders and baseline values of headache severity. Other characteristics of migraine attacks including the duration of attacks and headache daily results were not altered following zinc supplementation either before or after controlling for covariates.

CONCLUSION

Zinc supplementation had a beneficial effect on the frequency of migraine attacks in migraine patients. Additional well-designed clinical trials with a long period of intervention and different dosages of zinc are required.

TRIAL REGISTRATION CODE

IRCT20121216011763N23 at www.irct.ir .

A Common Insecticide Induced-Oxidative Stress in Wistar Rats: Significance for Humans and Implications for Nutritional Modulation of Insecticide Toxicity

OBJECTIVE

This study examined the levels of selected micronutrients and associated biochemical changes in rats exposed to Baygon® insecticide. Arsenic is a toxic metalloid commonly used in insecticides manufacture but unheralded.

METHODS

Fifteen rats, divided into three equal groups: Group I (control); group II (administered 2.5 mg/kg sodium arsenite (SA) on alternate days for four weeks); group III (exposed to 14.0 mL Baygon^® m^-3 cage volume daily for four weeks). Serum levels of arsenic (As), selenium (Se) and zinc (Zn) were determined using flame atomic absorption spectrophotometry (FAAS). Reduced glutathione (GSH), glutathione peroxidase (GPx), and total protein (TP) were determined spectrophotometrically.

RESULTS

Arsenic and Se levels were significantly raised in groups II and III compared with control (p < 0.05), unlike Zn levels that were significantly decreased in groups II and III (p < 0.05) in both. No significant change in the activity of GPx; though the activity increased in the group treated with SA, but decreased in the group treated with Baygon^® compared to control (P < 0.05). Histology of the liver and lung was unaltered in control, but in contrast, the SA-treated group demonstrated moderate fibrous hyperplasia with prominent highly infiltrated portal area in the liver; while the lung revealed thickened alveolar walls from proliferated pneumocytes. In the Baygon^®-treated group, there was mild hyperplasia of the fibrous connective tissue and congested prominent portal areas; while the lung exhibited severe thickened alveolar walls due to proliferated pneumocytes.

CONCLUSION

Exposure of rats to Baygon^® elicited alteration of key trace elements involved in the antioxidant system, culminating in oxidative stress with attendant deleterious effects. One significance of this for humans is that it has great potentials for possible nutritional modulation of insecticide toxicity with micronutrients, especially with zinc, holding great promise in tropical developing countries.

Effect of Zn Supplementation on Trace Element Status in Rats with Diet-Induced Non-alcoholic Fatty Liver Disease

The present study aimed to assess the effect of Zn supplementation on trace element levels in the liver, serum, and hair of rats with dietary-induced non-alcoholic fatty liver disease (NAFLD). A total of 26 3-month-old female Wistar rats were divided into four groups: control, NAFLD, Zn-supplemented (227 mg/L zinc as Zn sulfate Zn(SO)₄ dissolved in a drinking water), and NAFLD-Zn-supplemented. NAFLD was verified by histological assessment of liver samples. The serum was examined for routine biochemical parameters. Trace elements content was assessed using inductively coupled plasma mass spectrometry (ICP-MS). Zn treatment resulted in an improvement in liver weight and morphology. Dietary supplementation with Zn prevented NAFLD-induced decrease liver Co. The tendency to increase liver Fe in the Zn-treated group was observed. Zn treatment decreased hepatic Al and serum V levels. However, Zn administration did not affect NAFLD-induced I, Mn, and Se depletion in the liver. Hair Zn levels raised in Zn-supplemented groups. Conclusively, the results of the study indicate that Zn supplementation could have a beneficial effect in modulation of the altered trace element status and liver morphology. HIGHLIGHTS: •Zn treatment improved liver weight and morphology in rats with NAFLD. •Zn supplementation decreased liver Al in NAFLD. •Treatment by Zn prevented depletion of liver Co. •Zn decreased serum V and increased hair Zn levels. •No effect of Zn on NAFLD-induced hepatic I, Mn and Se depletion was observed.

Zinc exerts its renal protection effect on arsenic-exposed common carp: A signaling network comprising Nrf2, NF-κB and MAPK pathways

Epidemiological and laboratory investigations have extensively indicated that arsenic exposure accounts for several kidney diseases. Zinc has been suggested as a possible natural preventive and therapeutic agent. This study is designed to explore the beneficial effect of zinc supplementation against arsenic-induced renal toxicity in common carp, and the results point to signaling pathway possibly compromised. In the present study, renal injury was induced in common carp by waterborne exposure to arsenic (2.83 mg/L) for 30 days, and zinc (1 mg/L) was simultaneously supplemented. First, the arsenic-exposed fish showed histological and functional renal alterations (indicated by hematoxylin-eosin staining, biochemical indexes and a TUNEL assay). Moreover, as a reactive oxygen species (ROS) stimulant, arsenic was found to induce oxidative toxicity as determined by increased renal ROS, malondialdehyde, protein carbonyl and 8-hydroxydeoxyguanosine levels. When antioxidant-mediation attempts (through superoxide dismutase and glutathione)-mediated to restore homeostasis failed and ROS increased to extreme levels, inflammation (indicated by elevated inducible nitric oxide synthetase, tumor necrosis factor-alpha and interleukins levels) and apoptosis (through both mitochondrial- and death receptor-dependent pathways) were triggered. However, abnormalities in the upstream mediators Nrf2, NF-κB and MAPK were significantly ameliorated and blocked by treatment with zinc. In conclusion, zinc exerts a substantial protective effect against arsenic-triggered subchronic renal injury in common carp via the amelioration of oxidative stress, suppression of apoptosis and reduced inflammation through Nrf2, NF-κB and MAPK signaling.

Treatment of melasma: a review of less commonly used antioxidants

Melasma, a common cause for seeking dermatologic care, is a chronic condition of skin hyperpigmentation. With a poorly understood pathogenesis, and no universal cure, melasma is a challenge for many dermatologists. For decades, there has been investigation into the role of oxidative stress in melasma. In this literature review, we introduce the role of oxidative stress in melasma and discuss the function of various topical and oral antioxidant therapies for patients suffering from melasma. Numerous studies have shown efficacy of various antioxidant therapies for treatment of hyperpigmentation, and in this review, we focus primarily on those with less widespread use. Vitamin E, niacinamide, polypodium leucotomos, pycnogenol, grape seed extract, amino fruit acids, phytic acid, zinc, silymarin, Korean red ginseng powder, plant extracts, and parsley all have well-demonstrated evidence of antioxidant properties, and these substances have been studied in the context of skin hyperpigmentation. Although there is conflicting evidence of their therapeutic efficacy, the use of these naturally occurring substances is promising for patients and medical providers seeking alternative therapeutic options.

Efficacy of Adjunctive Zinc in Improving the Treatment Outcomes in Hospitalized Children with Pneumonia: A Randomized Controlled Trial

BACKGROUND

The mortality rate of pneumonia is high, placing a huge burden on developing countries. Healthcare professionals use zinc as an adjunctive treatment for children with pneumonia; however, this contradicts with some published reports. Thus, this study aimed to assess the efficacy of zinc supplementation on the treatment outcomes of pneumonia.

METHODS

A randomized, double-blind, placebo-controlled trial was conducted on hospitalized children with pneumonia. The children randomly received either zinc bis-glycinate (15 mg elemental zinc) or placebo, twice per day. The primary outcome was the resolution time of pneumonia, and the secondary outcomes were the duration of hospitalization and the recovery times of each clinical symptom.

RESULTS

Out of the 91 children, 65 (71.4%) were males. The resolution period of clinical pneumonia was significantly shorter in the zinc group than the placebo group (48 and 72 h, respectively; hazard ratio = 0.585, 95% confidence interval 0.377-0.908). Similarly, the hospitalization period and the resolution period of fever were shorter in the zinc group [96 and 144 h (p = 0.008), and 24 and 42 h (p = 0.002), respectively]. Children receiving zinc needed a median of 28 h to reach the normal level of oxygen saturation compared to 48 h required by children under placebo (p = 0.014).

CONCLUSION

Zinc supplementation enhanced the treatment outcomes of pneumonia, by reducing the resolution period of pneumonia and normalizing oxygen levels and body temperature. The length of hospital stay for children receiving zinc was shorter than those receiving placebo.

Zinc and Autophagy in Age-Related Macular Degeneration

Zinc supplementation is reported to slow down the progression of age-related macular degeneration (AMD), but there is no general consensus on the beneficiary effect on zinc in AMD. As zinc can stimulate autophagy that is declined in AMD, it is rational to assume that it can slow down its progression. As melanosomes are the main reservoir of zinc in the retina, zinc may decrease the number of lipofuscin granules that are substrates for autophagy. The triad zinc–autophagy–AMD could explain some controversies associated with population studies on zinc supplementation in AMD as the effect of zinc on AMD may be modulated by genetic background. This aspect was not determined in many studies regarding zinc in AMD. Zinc deficiency induces several events associated with AMD pathogenesis, including increased oxidative stress, lipid peroxidation and the resulting lipofuscinogenesis. The latter requires autophagy, which is impaired. This is a vicious cycle-like reaction that may contribute to AMD progression. Promising results with zinc deficiency and supplementation in AMD patients and animal models, as well as emerging evidence of the importance of autophagy in AMD, are the rationale for future research on the role of autophagy in the role of zinc supplementation in AMD.

Interleukin-1β and Cancer

Within a tumor, IL-1β is produced and secreted by various cell types, such as immune cells, fibroblasts, or cancer cells. The IL1B gene is induced after "priming" of the cells and a second signal is required to allow IL-1β maturation by inflammasome-activated caspase-1. IL-1β is then released and leads to transcription of target genes through its ligation with IL-1R1 on target cells. IL-1β expression and maturation are guided by gene polymorphisms and by the cellular context. In cancer, IL-1β has pleiotropic effects on immune cells, angiogenesis, cancer cell proliferation, migration, and metastasis. Moreover, anti-cancer treatments are able to promote IL-1β production by cancer or immune cells, with opposite effects on cancer progression. This raises the question of whether or not to use IL-1β inhibitors in cancer treatment.

Zinc Deficiency Promoted Fibrosis via ROS and TIMP/MMPs in the Myocardium of Mice

Zinc (Zn) is an important trace element in the body that has antioxidant effects. It has been proven that Zn deficiency can cause oxidative stress. The purpose of the present study was to clarify the effect and mechanism of Zn deficiency on myocardial fibrosis. Mice were fed with different Zn levels dietary for 9 weeks: Zn-normal group (ZnN, 34 mg Zn/kg), Zn-deficient group (ZnD, 2 mg Zn/kg), and Zn-adequate group (ZnA, 100 mg Zn/kg). We found that the Zn-deficient diet reduced the Zn concentration in myocardial tissue. Moreover, the TUNEL results demonstrated that cardiomyocytes in the ZnD group died in large numbers. Furthermore, ROS levels were significantly increased, and metallothionein (MT) expression levels decreased in the ZnD group. The results of Sirius Red staining indicated an increase in collagen in the ZnD group. Moreover, the ELISA results showed that collagen I, III, and IV and fibronectin (FN) were increased. In addition, the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) was detected by RT-qPCR. The results showed that the expression of TIMP-1 in the ZnD group was increased, while MMPs were decreased. Immunohistochemical results showed an increase in the content of α-smooth muscle actin (α-SMA), while H&E staining showed an increase in interstitial width and a decrease in the number of cardiac cells. All data suggest that Zn deficiency enhances the oxidative stress response of myocardial tissue and eventually triggers myocardial fibrosis.

Physical, nutritional, and sensory quality of rice-based biscuits fortified with safou (Dacryodes edulis) fruit powder

The reduction of postharvest losses in rice and safou is imperative to increase productivity in their respective value chains. In this study, fine broken rice grains were used to produce rice flour and subsequently rice-based biscuits. The biscuits were further fortified with safou powder, and the physical, nutritional, and sensory quality and stability during storage of the different types of biscuits were analyzed using standard methods. Fine or nonsandy biscuits had peak particle size of 500 µm, while medium (slightly sandy) and large (sandy) biscuits had peak particle sizes of 1,000 µm and 1,400 µm, respectively. The hardness varied from 5.7 ± 2.3 N for biscuits with large particles to 16.1 ± 4.4 N for biscuits with fine particles. Fortification of biscuits with sour safou increased the protein and amino acid content of the biscuits. Tryptophan was absent in both safou and the biscuits produced. There was an increase in phosphorus, potassium, calcium, magnesium, copper, iron, manganese, and aluminum following fortification with safou. Nonsandy biscuits dissolved faster in the mouth (melt) during consumption than the other biscuits although most of the biscuits were perceived to be low in melting and buttery. Nonsandy biscuits were rated as "very good," while slightly sandy and sandy were rated as "good." Safou rice-based biscuits were perceived as "very good," while simple rice biscuits were perceived as "good." Fortification of rice biscuits with safou increased the protein, essential amino acid, and mineral contents of the biscuits with very appreciable taste. These biscuits can be used to help fight protein, iron, and zinc malnutrition and in mitigating postharvest losses of underutilized broken rice and safou especially sour safou.

Tackle the free radicals damage in COVID-19

COVID-19 is a severe pandemic which has caused a devastating amount of loss in lives around the world, and yet we still don't know how to appropriately treat this disease. We know very little about the pathogenesis of SARS-CoV-2, the virus which induces the COVID-19. However, COVID-19 does share many similar symptoms with SARS and influenza. Previous scientific discoveries learned from lab animal models and clinical practices shed light on possible pathogenic mechanisms in COVID-19. In the past decades, accumulated scientific findings confirmed the pathogenic role of free radicals damage in respiratory virus infection. Astonishingly very few medical professionals mention the crucial role of free radical damage in COVID-19. This hypothesis aims to summarize the crucial pathogenic role of free radical damage in respiratory virus induced pneumonia and suggest an antioxidative therapeutic strategy for COVID-19.

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Additional scheme figure is attached.

Consumption of Raw Herbal Medicines Is Associated with Major Public Health Risks amongst Ugandans

Background

Community consumption of herbal plants in developing countries is a common practice, however, scarcity of information on their physiochemical composition is a major public health concern. In Uganda, Vernonia amygdalina is of interest in rural communities due to its therapeutical action on both bacterial and protozoal parasites, however no studies have been conducted to assess the heavy metal concentrations in traditional plants used in alternative medicine. The aim of the study was to establish concentrations of heavy metals in Vernonia amygdalina, model the estimated daily intake (EDI), and assess both the non-cancer-related health risk using the target hazard quotient (THQ), and the risk related to cancer through the incremental lifetime cancer risk (ILCR) for the Ugandan population.

Methods

Leaves of Vernonia amygdalina were collected from 20 georeferenced villages and processed into powder in the laboratory using standard methods. These were then analyzed in the laboratory using an atomic absorption spectrometer for lead (Pb), chromium (Cr), copper (Cu), zinc (Zn), cobalt (Co), iron (Fe), cadmium (Cd), and nickel (Ni). Concentrations were compared against the World Health Organization (WHO) limits. The EDI, THQ, and ILCR were modelled and significance was measured at 95% confidence.

Results

The study showed that mean ± SEM concentrations of heavy metals were highest in the order of Cr, 121.8 ± 4.291 ppm > Ni, 84.09 ± 2.725 ppm > Zn, 53.87 ± 2.277 ppm > Pb, 40.61 ± 3.891 ppm > Cu, 28.75 ± 2.202 ppm > Fe, 14.15 ± 0.7271 ppm > Co, 7.923 ± 0.7674 ppm > Cd, 0.1163 ± 0.005714 ppm. Concentrations of Pb, Cr, Zn, Co, and Ni were significantly higher than the WHO limits. The EDI was significantly higher in children than in adults, demonstrating an increased risk of toxicity in children. The THQ and ILCR were over 1000 times higher in all Ugandans, demonstrating the undesirable health risks following oral consumption of Vernonia amygdalina due to very high Cr and Ni toxicities, respectively.

Conclusion

Consumption of raw Vernonia amygdalina was associated with a high carcinogenic risk, demonstrating a need to enact policies to promote physiochemical screening of herbal medicines used in developing countries against toxic compounds.

CircRNA ZNF609 in peripheral blood leukocytes acts as a protective factor and a potential biomarker for coronary artery disease

Background

Circular RNAs (circRNAs) have been reported to aberrantly express in coronary artery disease (CAD). Due to their special structures, circRNAs have the potential to be specific and stable markers. We conducted this study to explore circZNF609's function in atherosclerosis and to evaluate its predictive values for CAD.

Methods

About 330 CAD patients and 209 controls were enrolled and the expression of circZNF609 in peripheral blood leukocytes (PBLs) was detected by quantitative real time polymerase chain reaction (RT-PCR). Spearman correlation, multivariate regression, multivariate logistic regression and receiver operating characteristic curve (ROC) were performed. Moreover, circZNF609 was overexpressed in mice macrophage RAW264.7 to investigate its influence on inflammatory cytokines. Finally, bioinformatics analysis was executed to excavate the potential downstream pathway of circZNF609.

Results

The expression level of circZNF609 in PBLs of CAD patients was significantly decreased compared with the controls (the fold changes of 0.4133, P<0.0001). The logistic regression analysis showed that decreased circZNF609 expressions were independently associated with increased risks of CAD. The area under the ROC curve was 0.761 (95% CI: 0.721-0.800, P<0.0001). Furthermore, the circZNF609 expression level was correlated with C-reactive protein (r=-0.138, P=0.026) and lymphocyte counts (r=0.16, P=0.01). After overexpression of circZNF609 in RAW264.7 cells, the expression level of IL-6 (P<0.001) and TNF-α (P<0.01) were significantly decreased and IL-10 was significantly increased (P<0.001). Bioinformatics analysis suggested that the abnormal expression of circZNF609 might probably sponge miRNA to modulate the inflammation cytokines.

Conclusions

CircRNA ZNF609 played an anti-inflammatory role and was an independent protective factor for CAD. It represented a moderate diagnostic value and might provide a new therapeutic target for CAD.

Recent aspects of the effects of zinc on human health

Zinc (Zn) is one of the most important essential nutrients of great public health significance. It is involved in numerous biological functions and it is considered as a multipurpose trace element, due to its capacity to bind to more than 300 enzymes and more than 2000 transcriptional factors. Its role in biochemical pathways and cellular functions, such as the response to oxidative stress, homeostasis, immune responses, DNA replication, DNA damage repair, cell cycle progression, apoptosis and aging is significant. Zn is required for the synthesis of protein and collagen, thus contributing to wound healing and a healthy skin. Metallothioneins are metal-binding proteins and they are potent scavengers of heavy metals, including Zn, and protect the organism against stress. Zn deficiency is observed almost in 17% of the global population and affects many organ systems, leading to dysfunction of both humoral and cell-mediated immunity, thus increasing the susceptibility to infection. This review gives a thorough insight into the most recent evidence on the association between Zn biochemistry and human pathologies, epigenetic processes, gut microbial composition, drug targets and nanomedicine.

The Relevance of Oxidative Stress in the Pathogenesis and Therapy of Retinal Dystrophies

Retinal cell survival requires an equilibrium between oxygen, reactive oxygen species, and antioxidant molecules that counteract oxidative stress damage. Oxidative stress alters cell homeostasis and elicits a protective cell response, which is most relevant in photoreceptors and retinal ganglion cells, neurons with a high metabolic rate that are continuously subject to light/oxidative stress insults. We analyze how the alteration of cellular endogenous pathways for protection against oxidative stress leads to retinal dysfunction in prevalent (age-related macular degeneration, glaucoma) as well as in rare genetic visual disorders (Retinitis pigmentosa, Leber hereditary optic neuropathy). We also highlight some of the key molecular actors and discuss potential therapies using antioxidants agents, modulators of gene expression and inducers of cytoprotective signaling pathways to treat damaging oxidative stress effects and ameliorate severe phenotypic symptoms in multifactorial and rare retinal dystrophies.

Trace Elements, PPARs, and Metabolic Syndrome

Metabolic syndrome (MetS) is a constellation of metabolic derangements, including central obesity, insulin resistance, hypertension, glucose intolerance, and dyslipidemia. The pathogenesis of MetS has been intensively studied, and now many factors are recognized to contribute to the development of MetS. Among these, trace elements influence the structure of proteins, enzymes, and complex carbohydrates, and thus an imbalance in trace elements is an independent risk factor for MetS. The molecular link between trace elements and metabolic homeostasis has been established, and peroxisome proliferator-activated receptors (PPARs) have appeared as key regulators bridging these two elements. This is because on one hand, PPARs are actively involved in various metabolic processes, such as abdominal adiposity and insulin sensitivity, and on the other hand, PPARs sensitively respond to changes in trace elements. For example, an iron overload attenuates hepatic mRNA expression of Ppar-α; zinc supplementation is considered to recover the DNA-binding activity of PPAR-α, which is impaired in steatotic mouse liver; selenium administration downregulates mRNA expression of Ppar-γ, thereby improving lipid metabolism and oxidative status in the liver of high-fat diet (HFD)-fed mice. More importantly, PPARs' expression and activity are under the control of the circadian clock and show a robust 24 h rhythmicity, which might be the reasons for the side effects and the clinical limitations of trace elements targeting PPARs. Taken together, understanding the casual relationships among trace elements, PPARs' actions, and the pathogenesis of MetS is of great importance. Further studies are required to explore the chronopharmacological effects of trace elements on the diurnal oscillation of PPARs and the consequent development of MetS.

Impact of zinc oxide nanoparticles on thioredoxin-interacting protein and asymmetric dimethylarginine as biochemical indicators of cardiovascular disorders in gamma-irradiated rats

Nanoparticle is a microscopic particle that has been existed in a wide range of biotechnological purposes. Zinc oxide nanoparticles (ZnO-NPs) have fewer environmental hazards and have shown positive impacts in the medical field. This work aimed to observe the effects of low and high doses of ZnO-NPs on heart injury induced by ionizing radiation (IR). Animals were irradiated by 8 Gy of gamma rays and ZnO-NPs (10 and 300 mg/Kg/day) were orally delivered to rats 1 hour after irradiation. Animals were dissected on 15th day postirradiation. Data showed that the oxidative damage resulted from radiation exposure, appeared by marked increments in the malondialdehyde (MDA) content and the level and protein expression of thioredoxin-interacting protein (TXNIP) with a noticeable decline in the level and expression of thioredoxin 1 (Trx-1) and thioredoxin reductase (TrxR), as well as glutathione (GSH) level and the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Moreover, radiation-induced inflammation, manifested by a noticeable elevation in the level of tumor necrotic factor-alpha (TNF-α), interleukin-18 (IL-18), and C-reactive protein (CRP). Additionally, endothelial dysfunction marked with a high level of asymmetric dimethylarginine (ADMA), total nitrite/nitrate (NOx), intercellular adhesion molecule 1 (ICAM-1), homocysteine (Hcy), creatine kinase (CK-MB), cardiac troponin-I (cTn-I), and lactate dehydrogenase (LDH). In addition, a decrease of zinc (Zn) level in the cardiac tissue was recorded. ZnO-NPs treatment (10 mg/kg) mitigated the oxidative stress and inflammation effects on the cardiovascular tissue through the positive modulations in the studied parameters. In contrast, ZnO-NPs treatment (300 mg/kg) induced cardiovascular toxicity of normal rats and elevated the deleterious effects of radiation. In conclusion, ZnO-NPs at a low dose could mitigate the adverse effects on cardiovascular tissue induced by radiation during its applications, while the high dose showed morbidity and mortality in normal and irradiated rats.

Lentinula edodes as a Source of Bioelements Released into Artificial Digestive Juices and Potential Anti-inflammatory Material

Lentinula edodes (shiitake), an edible and medicinal mushroom, was chosen for this study with the aim of evaluating the possibility of release of bioelements into artificial digestive juices and analyzing the anti-inflammatory properties. The extracts were prepared from fruiting bodies and biomass enriched with copper (Cu), zinc (Zn), and selenium (Se). The content of bioelements was analyzed by total reflection X-ray fluorescence method. Relatively low content of elements was observed in the fruiting bodies: Cu-1.6, Zn-7.6, and Se-0.12 mg/100 g d.w. compared to mycelial cultures. The anti-inflammatory properties were evaluated in RAW 264.7 cells. Based on the levels of cyclooxygenase 2 protein, nuclear factor erythroid 2-related factor 2, and peroxisome proliferator-activated receptor γ determined using Western blot technique, it was found that the addition of bioelements enhanced the anti-inflammatory properties of mycelium. This indicates that L. edodes cultured on a suitable medium may be used as a potential component of anti-inflammatory products.

Antioxidant and Anti-Inflammatory Effects of Different Zinc Sources on Diquat-Induced Oxidant Stress in a Piglet Model

Zinc (Zn) plays a crucial role in reducing oxidative stress and diarrhea in postweanling piglets. This study is aimed at comparing the effects of zinc chelate of 2-hydroxy-4 methyl-thio butanoic acid (HMZn) and ZnSO₄ on the oxidative stress in weaned piglets. A total of 32 piglets were randomly divided into 4 treatments: CON: basal diet+80 mg/kg Zn as ZnSO₄; DIQ: basal diet+80 mg/kg Zn as ZnSO₄; HMZn: basal diet+200 mg/kg Zn as HMZn; and ZnSO₄: basal diet+200 mg/kg Zn as ZnSO₄. On day 15, the DIQ, HMZn, and ZnSO₄ groups were injected intraperitoneally with diquat except for the CON group. The trial lasted 21 days. The results showed that zinc sources did not influence the growth performance during the first 14 days. But HMZn increased activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and total antioxidant capacity (T-AOC) in serum (P < 0.05). After diquat injection, the fecal score was decreased in the HMZn group. Both HMZn and ZnSO₄ increased the activities of GPX and T-AOC in serum and the relative mRNA expressions of hepatic and renal Nrf2, SOD1, and GPX compared with the DIQ group (P < 0.05). Moreover, the relative mRNA expression of inflammatory factors in the small intestine, liver, and kidney was downregulated; the phosphorylation of NF-κB protein was inhibited in the HMZn group compared with the DIQ and ZnSO₄ groups (P < 0.05). In general, HMZn showed notable advantage over ZnSO₄ in reducing diarrhea and improving antioxidant and anti-inflammatory ability in piglets challenged with diquat.

Adjuvant Therapies in Diabetic Retinopathy as an Early Approach to Delay Its Progression: The Importance of Oxidative Stress and Inflammation

Diabetes mellitus (DM) is a progressive disease induced by a sustained state of chronic hyperglycemia that can lead to several complications targeting highly metabolic cells. Diabetic retinopathy (DR) is a multifactorial microvascular complication of DM, with high prevalence, which can ultimately lead to visual impairment. The genesis of DR involves a complex variety of pathways such as oxidative stress, inflammation, apoptosis, neurodegeneration, angiogenesis, lipid peroxidation, and endoplasmic reticulum (ER) stress, each possessing potential therapeutic biomarkers. A specific treatment has yet to be developed for early stages of DR since no management is given other than glycemic control until the proliferative stage develops, offering a poor visual prognosis to the patient. In this narrative review article, we evaluate different dietary regimens, such as the Mediterranean diet, Dietary Pattern to Stop Hypertension (DASH) and their functional foods, and low-calorie diets (LCDs). Nutraceuticals have also been assessed in DR on account of their antioxidant, anti-inflammatory, and antiangiogenic properties, which may have an important impact on the physiopathology of DR. These nutraceuticals have shown to lower reactive oxygen species (ROS), important inflammatory factors, cytokines, and endothelial damage biomarkers either as monotherapies or combined therapies or concomitantly with established diabetes management or nonconventional adjuvant drugs like topical nonsteroidal anti-inflammatory drugs (NSAIDs).

Zinc alleviates maneb-induced kidney injury in adult mice through modulation of oxidative stress, genotoxicity, and histopathological changes

Zinc is one of the important essential trace minerals to human health due to its antioxidant properties. The present study was conducted to elucidate its potential protective role against maneb-induced nephrotoxicity. For this purpose, animals were randomly divided into four groups of six each. Mice of group I (negative controls) have received daily 0.5 ml of distilled water, a solvent of maneb. Mice of group II (MB) have received 30 mg/kg bw of maneb daily by intraperitoneal way. Mice of group III (MB + Zn) have received the same dose of maneb as group II, along with ZnSO4 (30 mg/kg bw) daily. Mice of group IV (Zn), considered as positive controls, have received the same dose of ZnSO4 as group III daily. Our results revealed that ZnSO4 co-administration to maneb-treated mice decreased kidney levels of malondialdehyde, hydrogen peroxide, protein carbonyls, and advanced oxidation protein products; the levels of non-enzymatic antioxidants like vitamin C, glutathione, and metallothionein. It recovered the alteration of antioxidant enzyme activities (catalase, superoxide dismutase, and glutathione peroxidase) and attenuated DNA fragmentation. Furthermore, this essential trace element was also able to alleviate kidney biomarkers' alterations by lowering plasma levels of creatinine, urea, uric acid, and lactate dehydrogenase. In addition, the histopathological changes induced by maneb were improved following zinc administration. Our results indicated that zinc might be beneficial against maneb-induced renal oxidative damage in mice.

Deoxynivalenol-induced alterations in the redox status of HepG2 cells: identification of lipid hydroperoxides, the role of Nrf2-Keap1 signaling, and protective effects of zinc

Deoxynivalenol (DON) is a type B trichothecenes that is widely contaminating human and animal foods, leading to several toxicological implications if ingested. Induction of oxidative stress and production of lipid peroxides were suggested to be the reasons for DON-induced cytotoxicity. However, detailed and comprehensive profiling of DON-related lipid hydroperoxides was not identified. Furthermore, the mechanisms behind DON-induced cytotoxicity and oxidative stress have received less attention. Zinc (Zn) is an essential element that has antioxidant activities; however, the protective effects of Zn against DON-induced adverse effects were not examined. Therefore, this study was undertaken to investigate DON-induced cytotoxicity and oxidative damage to human HepG2 cell lines. Furthermore, a quantitative estimation for the formed lipid hydroperoxides was conducted using LC-MS/MS. In addition, DON-induced transcriptomic changes on the inflammatory markers and antioxidant enzymes were quantitatively examined using qPCR. The protective effects of Zn against DON-induced cytotoxicity and oxidative stress, the formation of lipid hydroperoxides (LPOOH), and antioxidant status in HepG2 cells were investigated. Finally, the effects of DON and Zn on the Nrf2-Keap1 pathway were further explored. The achieved results indicated that DON caused significant cytotoxicity in HepG2 cells accompanied by significant oxidative damage and induction of the inflammatory markers. Identification of DON-related LPOOH revealed the formation of 22 LPOOH species including 14 phosphatidylcholine hydroperoxides, 5 triacylglycerol hydroperoxides, and 3 cholesteryl ester hydroperoxides. DON caused significant downregulation of Nrf2-regulated antioxidant enzymes. Zn administration led to significant protection of HepG2 cells against DON-induced adverse effects, probably via activation of the Nrf2-Keap1 pathway.

Effect of zinc oxide nanoparticles on broilers' performance and health status

The current study investigated the effects of zinc oxide nanoparticles (ZONPs) and oxytetracycline (OTC) supplementation on broilers' behavior, performance, carcass quality, biochemical parameters, and intestinal microbial populations and birds' response to Newcastle disease (ND) vaccine. A total of 336 seven-day-old IR broiler chicks were randomly allotted to six dietary treatments containing 0, 10, 20, 30 and 40 ppm ZONPs or 50 ppm OTC. Each diet was fed to 7 replicates (8 birds/pen). The results clarified that 10 ppm ZONPs significantly improved the body weight gain and feed conversion in comparison to the control. No changes in behavior were recorded. The 10 ppm and 30 ppm ZONPs and OTC significantly reduced the gizzard weight in comparison to the control. While, 10 ppm ZONPs significantly increased the spleen weight, and all ZONPs doses increased bursa weight in comparison to the control and OTC groups. 20 ppm ZONPs increased the eviscerated yield and edible yield in comparison to the control and OTC groups. 40 ppm ZONPs increased pH, reduced meat color and overall acceptability in comparison to the control. In addition, results revealed that the 20 ppm ZONPs increased Calcium (Ca), High density low cholesterol (HDL-C), reduced urea (UA) and triglyceride (TG). Also, 40 ppm ZONPs and OTC increased creatinine (Cr) and reduced ND-HI titer in comparison to the control. For microbial population, OTC group was significantly lower than ZONPs groups in the total anaerobic, aerobic and lactobacilli count. In conclusion, the dietary inclusion of ZONPs can be applied as antibiotic growth promoter substitutions in broilers' diet. However, further investigations are still needed.

Evaluating the effectiveness of nonsteroidal anti-inflammatory drug(s) for relief of pain associated with temporomandibular joint disorders: A systematic review

AIM

The aim of this systematic review was to compile the latest evidence to assess the effectiveness of nonsteroidal anti-inflammatory drug(s) (NSAID) in patients with temporomandibular joint disorders (TMDs) in relieving pain. TMDs are a group of musculoskeletal disorders that affect the temporomandibular joint and/or masticatory muscles.

METHODS

After a literature review, a comprehensive search was conducted via Pubmed, Scopus, Google Scholar, and Cochrane databases with a systematic search strategy. The inclusion criteria were randomised controlled trials in humans, published in the last 50 years evaluating the effect of NSAIDs on TMDs. Although this duration chosen would potentially identify studies that have utilised outdated treatments, research methodology, and TMDs diagnostic criteria, and this has been considered before making clinical recommendation, it was used to advise future methodological changes necessary. The included studies were subjected to full-text review.

RESULTS

Out of 646 studies initially identified through searches, 12 were selected for full-text review of which 11 were included in the data synthesis. All 11 studies were randomised controlled trials. In total, 424 patients were included in this review. The earliest study included was 1996. Diagnostic criteria varied among all studies, and some did not specify enough signs and symptoms to construct a diagnosis. Intervention varied among all studies, as did the control. Nonspecific diagnosis, variable control groups, and heterogenous intervention protocols affected the outcome of this review. Despite the reduction of pain in the joint and/or masticatory muscles as well as improved range of motion, conclusive clinical recommendation could not be made.

CONCLUSION

Heterogeneity did not allow for definitive conclusion; however, there was some evidence to support the use of NSAIDs in patients with TMDs for relief of pain. Further studies with strict, consistent diagnostic criteria and treatment are required.

Bioactive Glass in a Rare Case of Osteomyelitis of the Heel in a Guillain-Barré Syndrome: A Case Report

Guillain-Barré syndrome (GBS) represents an acute inflammatory immune-mediated demyelinating polyradiculoneuropathy with an incidence of 0.6 per 100 000 people. In this article, we report the case of a 19-year-old girl affected by GBS since the age of 2 who presented at our clinic complaining for a chronic plantar hindfoot–infected ulceration. Serology showed increase of inflammatory markers and leukocytosis, and magnetic resonance imaging revealed osteomyelitis of calcaneum and soft tissue alterations with air bubbles. The patient was treated in our clinic by an integrated multidisciplinary approach consisting of immediate admission, soft tissue and bone debridement, and administration of antibiotics under the close control of infectious disease specialist. After the control of acute condition, the patient underwent negative pressure therapy associated with instillation of antiseptic solution until the restoration of bone and soft tissue loss of substance and, eventually, to the application of bioactive glass substitute until the achievement of complete wound healing.

Design and Synthesis of ZnII -Coordination Polymers Anchored with NSAIDs: Metallovesicle Formation and Multi-drug Delivery

A series of coordination polymers synthesized from a bis-pyridyl linker, namely 4,4'-azopyridine (L), selected non-steroidal-anti-inflammatory drugs (NSAIDs), namely diclofenac (Dic), ibuprofen (Ibu), flurbiprofen (Flu), mefenamic acid (Mefe), and naproxen (Nap), and Zn(NO₃ )₂ were characterized by single crystal X-ray diffraction. One of the coordination polymers, namely CP3 derived from Flu, was able to form metallovesicles in DMSO, DMSO/H₂ O and DMSO/DMEM (biological media) as revealed by TEM, AFM and DLS. Metallovesicle formation by CP3 was further supported by loading a fluorescent dye, namely calcein, as well as an anti-cancer drug, doxorubicin hydrochloride (DOX), as revealed by UV-vis and emission spectra, and fluorescence microscopy. DOX-loaded metallovesicles of CP3 (DOX@CP3-vesicle) could be delivered in vitro to a highly aggressive human breast cancer cell line, namely MDA-MB-231, as revealed by MTT and cell migration assays, and also cell imaging performed under laser scanning confocal microscope (LSCM). Thus, a proof of concept for developing a multi-drug delivery system derived from a metallovesicle for delivering an anti-cancer drug to cancer cells is demonstrated for the first time.

A Review of Micronutrients and the Immune System-Working in Harmony to Reduce the Risk of Infection

Immune support by micronutrients is historically based on vitamin C deficiency and supplementation in scurvy in early times. It has since been established that the complex, integrated immune system needs multiple specific micronutrients, including vitamins A, D, C, E, B6, and B12, folate, zinc, iron, copper, and selenium, which play vital, often synergistic roles at every stage of the immune response. Adequate amounts are essential to ensure the proper function of physical barriers and immune cells; however, daily micronutrient intakes necessary to support immune function may be higher than current recommended dietary allowances. Certain populations have inadequate dietary micronutrient intakes, and situations with increased requirements (e.g., infection, stress, and pollution) further decrease stores within the body. Several micronutrients may be deficient, and even marginal deficiency may impair immunity. Although contradictory data exist, available evidence indicates that supplementation with multiple micronutrients with immune-supporting roles may modulate immune function and reduce the risk of infection. Micronutrients with the strongest evidence for immune support are vitamins C and D and zinc. Better design of human clinical studies addressing dosage and combinations of micronutrients in different populations are required to substantiate the benefits of micronutrient supplementation against infection.

Zinc dysregulation in cancers and its potential as a therapeutic target

Zinc is an essential element and serves as a structural or catalytic component in many proteins. Two families of transporters are involved in maintaining cellular zinc homeostasis: the ZIP (SLC39A) family that facilitates zinc influx into the cytoplasm, and the ZnT (SLC30A) family that facilitates zinc efflux from the cytoplasm. Zinc dyshomeostasis caused by the dysfunction of zinc transporters can contribute to the initiation or progression of various cancers, including prostate cancer, breast cancer, and pancreatic cancer. In addition, intracellular zinc fluctuations lead to the disturbance of certain signaling pathways involved in the malignant properties of cancer cells. This review briefly summarizes our current understanding of zinc dyshomeostasis in cancer, and discusses the potential roles of zinc or zinc transporters in cancer therapy.

Zinc oxide nanoparticles for therapeutic purposes in cancer medicine

Zinc oxide nanoparticles are characterized by a good biocompatibility while providing a versatile potential as innovative therapeutic agents in cancer medicine.

A Comparative Evaluation on the Effect of Oral Zinc 50 mg with or without 0.1% Triamcinolone Orabase on Oral Lichen Planus

BACKGROUND

Lichen planus is a T-cell-mediated autoimmune disease, in which CD8+ T-cells releases the cytokines such as tumor necrosis factor-alpha and interleukin-12 disrupting basement membrane integrity. Treatment modalities were directed toward the relief in signs and symptoms and preventing recurrences. Zinc activates caspase-3 and DNA fragmentation, resulting in the apoptosis of keratinocytes. Prevention of matrix metalloproteinases1 (MMP1) activation, inhibits the Tcell accumulation in oral lichen planus (OLP) and by inhibiting MMP9, prevents the cleavage of collagen resulting in maintaining the integrity of the basement membrane.

OBJECTIVES

The main objective of the study is to compare the efficacy of oral zinc 50 mg and 0.1% triamcinolone Orabase with 0.1% triamcinolone Orabase alone on the healing process of symptomatic OLP.

MATERIALS AND METHODS

A total of forty participants were randomly categorized into two groups: Group A and Group B with 20 patients with OLP and having symptoms of burning sensation. Group A patients had received 0.1% triamcinolone Orabase twice daily application. Group B patients had provided with oral zinc 50 mg and 0.1% triamcinolone Orabase twice daily for 8 weeks. The follow-up period for both the groups was 6 months. Lesional size was measured by Thongprasom scale and burning sensation was assessed by visual analog scale at each visit till the cessation of treatment.

RESULTS

There was decrease in the burning sensation and lesional size from the first visit to follow-up period which was statistically significant in both groups (P = 0.000).

CONCLUSION

Oral zinc therapy was adjunctive in reducing the burning sensation and lesional size in the symptomatic OLP.

Dynamics of plasma micronutrient concentrations and their correlation with serum proteins and thyroid hormones in patients with paracoccidioidomycosis

Minerals, such as zinc, copper, and iron are reported to play roles in chronic infectious diseases; however, their role in paracoccidioidomycosis (PCM) remains unknown. This study aimed to examine the micronutrient dynamics and their correlation with serum proteins and thyroid hormones in patients with PCM. In 14 patients with PCM and 10 healthy subjects, we evaluated the body mass index (BMI) along with serum levels of hemoglobin, iron, ferritin, zinc, copper, magnesium, albumin, globulin, thyroid stimulating hormone (TSH), thyroxine (free T4), and triiodothyronine (T3). Evaluations were conducted at the first appointment, before treatment, and at the end of the first, second, fourth, and sixth month of PCM treatment. The control group was only evaluated once. We observed that before treatment, patients with PCM, had higher levels of copper and lower level of iron than those of the control group. After one month of treatment, the iron levels increased, whereas the levels of copper after six months of treatment. Reduction in inflammatory activity, indicated by the normalization of C-reactive protein, ferritin, albumin, and globulin levels, was observed during treatment. However, no correlation was observed between the serum levels of minerals and inflammatory activity or thyroid function in this study. In conclusion, our results showed higher serum copper levels in control group compared to those in pretreatment patients; the clinical importance of this observation should be investigated in further studies. After treatment, serum copper levels showed a tendency to decrease. In addition, serum iron levels were decreased at the stage of active disease, and were increased after treatment. Thus, serum iron levels can be used as a better biomarker for treatment control.

The Alterations of Copper and Zinc Homeostasis in Acute Appendicitis and the Clinical Significance

Copper (Cu) and zinc (Zn) are involved in inflammatory process. This study was to investigate the clinical significance of Cu and Zn homeostasis alterations in acute appendicitis (AA). One hundred twenty-two AA patients and 102 healthy controls were enrolled in this study. Of which, 85 patients' appendixes were collected after appendectomy. Another six appendixes from colon cancer patients were collected as tissue controls. The contents of Cu and Zn in serum or appendix were detected, and the Cu to Zn ratio (CZr) was calculated. The concentrations of serum ceruloplasmin (CP), Cu/Zn superoxide dismutase (SOD1), interleukin-6 (IL-6), and interleukin-22 in serum were measured, as well as the activity of CP and SOD1. The serum Zn concentration and SOD1 activity, appendix contents of Cu and Zn significantly decreased in AA patients, compared with those of controls, while serum CZr, concentrations of CP, SOD1, and IL-6, as well as CP activity increased significantly in AA patients. Additionally, serum concentrations of Zn, CP, CZr, or SOD1 activity varied in different pathological types of AA. Indicators such as serum SOD1 activity might serve as predictors for pathological classification before surgery. The serum Zn and CZr may be helpful for diagnosis of pure AA. The Cu and Zn homeostasis was altered in AA patients, which might contribute to inflammatory process of AA.

Neonatal murine engineered cardiac tissue toxicology model: Impact of dexrazoxane on doxorubicin induced injury

Doxorubicin (DOX) induced cardiotoxicity is a life-threatening side effect of chemotherapy and decreased cardiac function can present years after treatment. Despite the investigation of a broad range of pharmacologic interventions, to date the only drug shown to reduce DOX-related cardiotoxicity in preclinical studies and limited clinical trials is the iron chelating agent, dexrazoxane (DRZ), although the mechanisms responsible for DRZ mediated protection from DOX related cardiotoxicity remain unclear. Engineered cardiac tissues (ECTs) can be used for tissue repair strategies and as in vitro surrogate models to test cardiac toxicities and preventative countermeasures. Neonatal murine ECTs display cardiotoxicity in response to the environmental toxin, cadmium, and reduced cadmium toxicity with Zinc co-treatment, in part via the induction of the anti-oxidant Metallothionein (MT). We adapted our in vitro ECT model to determine the feasibility of using the ECT approach to investigate DOX-related cardiac injury and DRZ prevention. We found: (1) DOX induced dose and time dependent cell death in ECTs; (2) Zinc did not show protection from DOX cardiotoxicity; (3) MT overexpression induced by Zinc, low dose Cd pretreatment, or MT-overexpression (MT-TG) did not reduce ECT DOX cardiotoxicity; (4) DRZ reduced ECT DOX induced cell death; and (5) The mechanism of DRZ ECT protection from DOX cardiotoxicity was topoisomerase 2B (TOP2B) inhibition rather than reduced reactive oxygen species. Our data support the feasibility of ECTs as an in vitro platform technology for the investigation of drug induced cardiotoxicities including the role of TOP2B in DOX toxicity and DRZ mediated DOX toxicity prevention.

Effects of dietary zinc source on the metabolic and immunological response to lipopolysaccharide in lactating Holstein dairy cows

The objectives of this study were to evaluate the effects of replacing 40 mg/kg of Zn from Zn sulfate (control; CON) with Zn AA complex (AvZn) on metabolism and immunological responses following an intravenous lipopolysaccharide (LPS) challenge in lactating cows. Cows were randomly assigned to 1 of 4 treatments: (1) pair-fed (PF) control (PF-CON; 5 mL of saline; n = 5), (2) PF AvZn (PF-AvZn; 5 mL of saline; n = 5), (3) LPS euglycemic clamp control (LPS-CON; 0.375 μg of LPS/kg of BW; n = 5), and (4) LPS euglycemic clamp AvZn (LPS-AvZn; 0.375 μg of LPS/kg of BW; n = 5). Cows were enrolled in 3 experimental periods (P). During period 1 (3 d), cows received their respective dietary treatments and baseline data were obtained. During period 2 (P2; 2 d), a 12-h LPS euglycemic clamp was conducted or cows were PF to their respective dietary counterparts. During period 3 (P3; 3 d), cows received their dietary treatment and consumed feed ad libitum. Mild hyperthermia (1°C) was observed in LPS cows at 3 h postbolus. Throughout P2, the rectal temperature of LPS-AvZn cows was decreased (0.3°C) relative to LPS-CON cows. Administrating LPS decreased dry matter intake (47%) during P2, and by experimental design the pattern was similar in PF cohorts. During P3, dry matter intake from LPS cows remained decreased (15%) relative to PF cows. Milk yield from LPS cows decreased (54%) during P2 relative to PF cows, but it was similar during P3. During P2, somatic cell count increased 3-fold in LPS cows relative to PF controls. Dietary AvZn tended to decrease somatic cell count (70%) during P3 relative to LPS-CON cows. Insulin increased 7-fold in LPS cows at 12 h postbolus and remained increased (4-fold) for the duration of P2. Circulating glucagon from LPS cows increased (65%) during P2, and supplementing AvZn blunted the increase (30% relative to LPS-CON). During P2, circulating cortisol increased 7-fold post-LPS infusion relative to PF cows, and supplementing AvZn decreased cortisol (58%) from 6 to 48 h postbolus relative to LPS-CON cows. Administrating LPS increased circulating LPS-binding protein and serum amyloid A (3- and 9-fold, respectively) relative to PF cows. Compared with LPS-CON, LPS-AvZn cows had increased circulating serum amyloid A (38%) 24 h postbolus. The 12-h total glucose deficit was 36 and 1,606 g for the PF and LPS treatments, respectively, but was not influenced by Zn source. In summary, replacing a portion of the Zn sulfate with Zn AA complex appeared to reduce the inflammatory response but had no effect on the glucose deficit.

Role of Zinc in Immune System and Anti-Cancer Defense Mechanisms

The human body cannot store zinc reserves, so a deficiency can arise relatively quickly, e.g., through an improper diet. Severe zinc deficiency is rare, but mild deficiencies are common around the world. Many epidemiological studies have shown a relationship between the zinc content in the diet and the risk of cancer. The anti-cancer effect of zinc is most often associated with its antioxidant properties. However, this is just one of many possibilities, including the influence of zinc on the immune system, transcription factors, cell differentiation and proliferation, DNA and RNA synthesis and repair, enzyme activation or inhibition, the regulation of cellular signaling, and the stabilization of the cell structure and membranes. This study presents selected issues regarding the current knowledge of anti-cancer mechanisms involving this element.

Cytokine response after stimulation of culture cells by zinc and probiotic strain

Intestinal porcine epithelial cells were used for an in vitro analysis of mRNA expression levels of inflammatory cytokines (IL-8, IL-18) and transcriptional factors (MyD88 and NF-κβ). Cells were exposed to inorganic and organic zinc sources (in two different concentrations-50 μmol/L and 100 μmol/L) alone or combined with Lactobacillus reuteri B6/1, which was also applied individually. The total exposure time was 4 h. Quantitative reverse transcriptase PCR was used to determine expression levels of the aforementioned parameters. In general, upregulation was observed; however, a decrease of some mRNA's abundance was also determined. Differences in expression were analysed statistically using ANOVA and Tukey analyses. High relative expression was shown for IL-8, IL-18 and MyD88 in groups treated with 100 μmol/L of inorganic sources of zinc (ZnSO₄) (p < 0.05), while groups treated with the organic form did not exhibit significant changes in expression. Also, 50 μmol/L of either zinc source did not significantly modify the transcriptional profile of the cytokines and transcription factors, showing that even inorganic sources, at lower concentrations, do not elicit a significant inflammatory reaction. In summary, supplementation of organic zinc source (Gly-Zn chelate) ensures that IL-8, IL-18, MyD88 and NF-κβ expression levels are not positively regulated. In contrast, inorganic sources of zinc (ZnSO₄) could induce an inflammatory reaction. However, this response could be dampened if L. reuteri B6/1 is administered, showing the helpful aspect of using probiotics to modulate an inflammatory response. Conclusively, the use Gly-Zn chelate appears as an optimal alternative for Zn administration that does not compromise normal intestinal homeostasis.

Oxidative Stress as the Main Target in Diabetic Retinopathy Pathophysiology

Diabetic retinopathy (DR) is one of the most common complications of diabetes mellitus (DM) causing vision impairment even at young ages. There are numerous mechanisms involved in its development such as inflammation and cellular degeneration leading to endothelial and neural damage. These mechanisms are interlinked thus worsening the diabetic retinopathy outcome. In this review, we propose oxidative stress as the focus point of this complication onset.

Micronutrient Absorption and Related Outcomes in People with Inflammatory Bowel Disease: A Review

Inflammatory Bowel Disease (IBD) is a chronic disorder associated with immune dysregulation and chronic inflammation of the digestive tract. While it is poorly understood, the role of nutrition and nutrient status in the etiology of IBD and its associated outcomes has led to increased research relating to micronutrient deficiency. This review offers an overview of recent literature related to micronutrient absorption and outcomes in adults with IBD. Although the absorption and IBD-related outcomes of some micronutrients (e.g., vitamin D and iron) are well understood, other micronutrients (e.g., vitamin A) require further research. Increased research and clinician knowledge of the relationship between micronutrients and IBD may manifest in improved nutrient screening, monitoring, treatment, and outcomes for people living with IBD.

Why is it worth testing the ability of zinc to protect against ischaemia reperfusion injury for human application

Ischaemia (interruption in the blood/oxygen supply) and subsequent damage induced by reperfusion (restoration of blood/oxygen supply) ultimately leads to cell death, tissue injury and permanent organ dysfunction. The impact of ischaemia reperfusion injury (IRI) is not limited to heart attack and stroke but can be extended to patients undergoing surgeries such as partial nephrectomy for renal cancer, liver resection for colorectal cancer liver metastasis, cardiopulmonary bypass, and organ transplantation. Unfortunately, there are no drugs that can protect organs against the inevitable peril of IRI. Recent data show that a protocol incorporating specific Zn formulation, dosage, number of dosages, time of injection, and mode of Zn delivery (intravenous) and testing of efficacy in a large preclinical sheep model of IRI strongly supports human trials of Zn preconditioning. No doubt, scepticism still exists among funding bodies and research fraternity on whether Zn, a naturally occurring metal, will work where everything else has failed. Therefore, in this article, we review the conflicting evidence on the promoter and protector role of Zn in the case of IRI and highlight factors that may help explain the contradictory evidence. Finally, we review the literature related to the knowledge of Zn's mechanism of action on ROS generation, apoptosis, HIF activation, inflammation, and signal transduction pathways, which highlight Zn's likelihood of success compared to various other interventions targeting IRI.