Evaluation of elevated serum apelin-13 and D-dimer concentrations in individuals diagnosed with pulmonary embolism.

BACKGROUND: Given the limited specificity of D-dimer, there is a perceived need to discover a more precise marker for diagnosing individuals who are suspected of having pulmonary embolism (PE). In this study, by evaluating the increase in the serum level of Apelin-13 and D-dimer, we found valuable findings about Apelin-13, which can be suggested as an auxiliary and non-invasive diagnostic biomarker in individuals with suspected PE, based on the obtained results. METHODS: In this case-control study, 52 Iranian individuals were included, all of whom were suspected to have PE. These individuals were then divided into two groups based on the results of CT angiography, which is considered the gold standard imaging method for diagnosing PE. The two groups were patients with PE and patients without PE. Finally, the levels of certain markers in the serum were compared between the two groups. RESULTS: The mean serum D-dimer levels in patients with PE were significantly elevated (p < 0.001) in comparison to those without PE (1102.47 to 456.2 ng/ml). Furthermore, the mean level of Apelin-13 was significantly higher in patients with PE (49.8 to 73.11 ng/L) (p < 0.001). The cutoff point of Apelin-13 has been calculated at 58.50 ng/ml, with 90.9% sensitivity and 90% specificity. The D-dimer cutoff point was 500 ng/ml, with 95.5% sensitivity and 43.3% specificity. CONCLUSIONS: Based on the results of this study, the serum level of Apelin-13 can be used as a novel diagnostic and screening biomarker in patients with pulmonary thromboembolism.

MicroRNAs and Periodontal Disease: Helpful Therapeutic Targets?

Periodontal disease is the most common oral disease. This disease can be considered as an inflammatory disease. The immune response to bacteria accumulated in the gum line plays a key role in the pathogenesis of periodontal disease. In addition to immune cells, periodontal ligament cells and gingival epithelial cells are also involved in the pathogenesis of this disease. miRNAs which are small RNA molecules with around 22 nucleotides have a considerable relationship with the immune system affecting a wide range of immunological events. These small molecules are also in relation with periodontium tissues especially periodontal ligament cells. Extensive studies have been performed in recent years on the role of miRNAs in the pathogenesis of periodontal disease. In this review paper, we have reviewed the results of these studies and discussed the role of miRNAs in the immunopathogenesis of periodontal disease comprehensively. miRNAs play an important role in the pathogenesis of periodontal disease and maybe helpful therapeutic targets for the treatment of periodontal disease.

Determination of plasma transcobalamin-II and zinc levels in newly-diagnosed and long-standing grand mal epileptic patients.

Background: The changes of plasma transcobalamin-II (TCII) and Zinc (Zn) Levels in epileptic patients are not clearly understood. The aim of the current study was to evaluate the plasma contents of TCII and Zn levels in newly-diagnosed epileptic seizure patients, long-standing grand mal epileptic patients following treatment with sodium valproate and healthy control group. Methods: Thirty patients aged 36.76±12.91 years with newly-diagnosed and thirty long-standing grand mal epileptic patients aged 35.56 ±12.77 years were diagnosed based on the clinical symptoms. The control subjects were picked out from healthy individuals and matched to the patients, aged 36.30 ±12.80 years. Plasma Zn and TCN-2 was evaluated via spectrophotometry at 546 nm and 450 nm, respectively, using chimerical kits. Results: Plasma level of TCII in the newly-diagnosed epileptic seizures patients and long-standing grand mal epileptic patients were significantly increased, compared to the healthy controls [14.89 ±3.24 and 21.84± 2.73 vs. 9.55±1.24, (n=30)], respectively. Plasma level of Zn was decreased in the newly-diagnosed epileptic seizure patients, while it was increased in long-standing grand mal epileptic patients compared to the control group [69.28± 6.41 and 80.56 ±6.12 and vs.75.80±1.59, (n=30)], respectively. Conclusion: This study suggests that sodium valproate may disrupt the homeostatic balance of TCII and Zn, and cause abnormality of their serum level in newly-diagnosed epileptic seizure patients and long-standing grand mal epileptic patients. Further research is recommended to identify the underpinning for these changes.

Evaluation of the Salivary Matrix Metalloproteinase-9 in Women With Polycystic Ovaries Syndrome and Gingival Inflammation: A Case-Control Study.

Background Polycystic ovary syndrome (PCOS) is an endocrine disease of women of reproductive age that impacts their oral and systemic well-being. This study aimed to compare the gingival inflammation indices and matrix metalloproteinase-9 (MMP-9) of non-obese women with PCOS. Materials and methods This is a case-control study in which 78 women were referred to the Babol Clinic Hospital in Northern Iran between 2018 and 2019. They were divided into three groups: 26 women with PCOS and gingivitis, 26 women with PCOS with no gingivitis, and 26 women with no PCOS and no gingivitis as a control group. After recording the anthropometric and demographic variables, fasting saliva samples were taken from all participants before any periodontal intervention. These samples were transferred to Babol Molecular Cell Research Center under highly guaranteed cold-chain conditions to measure the serum levels of MMP-9. Periodontal status was evaluated for Gingival Index (GI), Plaque Index (PI), and Bleeding on Probing (BOP). Analysis of variance was used to compare the mean results for these indices. The significance level was considered when p ≤ 0.05. Results All the gingival indices were significantly higher for women with PCOS with gingivitis compared to the results for women from the other two groups. Similarly, women with PCOS showed high salivary MMP-9 levels but were within the normal reference ranges. Conclusion The gingival indices (GI, PI, and BOP) and salivary MMP-9 are higher in women with PCOS, regardless of the gingival status.

Vitamin D in respiratory viral infections: a key immune modulator?

Respiratory viral infections are common respiratory diseases. Influenza viruses, RSV and SARS-COV2 have the potential to cause severe respiratory infections. Numerous studies have shown that unregulated immune response to these viruses can cause excessive inflammation and tissue damage. Therefore, regulating the antiviral immune response in the respiratory tract is of importance. In this regard, recent years studies have emphasized the importance of vitamin D in respiratory viral infections. Although, the most well-known role of vitamin D is to regulate the metabolism of phosphorus and calcium, it has been shown that this vitamin has other important functions. One of these functions is immune regulation. Vitamin D can regulate the antiviral immune response in the respiratory tract in order to provide an effective defense against respiratory viral infections and prevention from excessive inflammatory response and tissue damage. In addition, this vitamin has preventive effects against respiratory viral infections. Some studies during the COVID-19 pandemic have shown that vitamin D deficiency may be associated with a higher risk of mortality and sever disease in patients with COVID-19. Since, more attention has recently been focused on vitamin D. In this article, after a brief overview of the antiviral immune response in the respiratory system, we will review the role of vitamin D in regulating the antiviral immune response comprehensively. Then we will discuss the importance of this vitamin in influenza, RSV, and COVID-19.

Quercetin: an effective polyphenol in alleviating diabetes and diabetic complications.

Various studies, especially in recent years, have shown that quercetin has beneficial therapeutic effects in various human diseases, including diabetes. Quercetin has significant anti-diabetic effects and may be helpful in lowering blood sugar and increasing insulin sensitivity. Quercetin appears to affect many factors and signaling pathways involved in insulin resistance and the pathogenesis of type 2 of diabetes. TNFα, NFKB, AMPK, AKT, and NRF2 are among the factors that are affected by quercetin. In addition, quercetin can be effective in preventing and ameliorating the diabetic complications, including diabetic nephropathy, cardiovascular complications, neuropathy, delayed wound healing, and retinopathy, and affects the key mechanisms involved in the pathogenesis of these complications. These positive effects of quercetin may be related to its anti-inflammatory and anti-oxidant properties. In this article, after a brief review of the pathogenesis of insulin resistance and type 2 diabetes, we will review the latest findings on the anti-diabetic effects of quercetin with a molecular perspective. Then we will review the effects of quercetin on the key mechanisms of pathogenesis of diabetes complications including nephropathy, cardiovascular complications, neuropathy, delayed wound healing, and retinopathy. Finally, clinical trials investigating the effect of quercetin on diabetes and diabetes complications will be reviewed.

Melatonin and inflammatory bowel disease: From basic mechanisms to clinical application.

Inflammatory bowel disease is a chronic inflammatory disease and has periods of recurrence and remission. Improper immune responses to gut flora bacteria, along with genetic susceptibility, appear to be involved in causing this complex disease. It seems dysbiosis and oxidative stress may also be involved in IBD pathogenesis. A significant number of clinical studies have shown an interesting association between sleep disturbances and IBD. Studies in animal models have also shown that sleep deprivation has a significant effect on the pathogenesis of IBD and can aggravate inflammation. These interesting findings have drawn attention to melatonin, a sleep-related hormone. Melatonin is mainly produced by the pineal gland, but many tissues in the body, including the intestines, can produce it. Melatonin can have an interesting effect on the pathogenesis of IBD. Melatonin can enhance the intestinal mucosal barrier, alter the composition of intestinal bacteria in favor of bacteria with anti-inflammatory properties, regulate the immune response, alleviate inflammation and attenuate oxidative stress. It seems that, melatonin supplementation is effective in relieving inflammation and healing intestinal ulcers in IBD animal models. Some clinical studies have also shown that melatonin supplementation as an adjuvant therapy may be helpful in reducing disease activity in IBD patients. In this review article, in addition to reviewing the effects of sleep disturbances and melatonin on key mechanisms involved in the pathogenesis of IBD, we will review the findings of clinical studies regarding the effects of melatonin supplementation on IBD treatment.

Polyphenols and inflammatory bowel disease: Natural products with therapeutic effects?

Inflammatory bowel disease (IBD) is a long-life disease with periods of recurrence and relief. Oxidative stress plays an important role in the pathogenesis of this disease. Recent years' studies in the field of IBD treatment mostly have focused on targeting cytokines and immune cell trafficking using antibodies and inhibitors, altering the composition of intestinal bacteria in the line of attenuation of inflammation using probiotics and prebiotics, and attenuating oxidative stress through antioxidant supplementation. Studies in animal models of IBD have shown that some polyphenolic compounds including curcumin, quercetin, resveratrol, naringenin, and epigallocatechin-3-gallate can affect almost all of the above aspects and are useful compounds in the treatment of IBD. Clinical studies performed on IBD patients have also confirmed the findings of animal model studies and have shown that supplementation with some of the above-mentioned polyphenolic compounds has positive effects in reducing disease clinical and endoscopic activity, inducing and maintaining remission, and improving quality of life. In this review article, in addition to a detailed reviewing the effects of the above-mentioned polyphenolic compounds on the events involved in the pathogenesis of IBD, the results of these clinical studies will also be reviewed.

Effect of lullaby on volume, fat, total protein and albumin concentration of breast milk in premature infants' mothers admitted to NICU: a randomized controlled trial.

BACKGROUND: Listening to music can reduce or manage stress, fatigue, and accompanying symptoms in mothers. Music increases oxytocin secretion which affects breast milk. This study aimed to examine the effect of lullaby on volume, fat, total protein and albumin concentration of breast milk in mothers of premature infants admitted to the NICU. METHODS: This clinical trial was performed on 100 primiparous mothers whose premature infants were hospitalized in the NICU of Ayatollah Rouhani Hospital from January 2020 to December 2020. Using block randomization method, the participants were divided into three groups: control (A), playing lullaby for mother (B) and playing lullaby for a mother while holding a photo of her own baby (C). The mothers of the intervention groups listened to lullabies through headphones for 30 minutes every morning for 6 days. On the first and the sixth day of birth, the volume of breast milk (ml) and two milliliters of breast milk samples of all three groups were measured and compared in terms of fat, albumin concentration and total protein (mg/DL). ANOVA, Paired T-Test and ANCOVA model (the included variables were: basic value of dependent variable, group type, Maternal age, Birth weight, Gestational age and Maternal weight) was used for analytical statistics. RESULTS: The difference between the mean compositions of breast milk before and after the intervention in three groups of A, B and C: in terms of the breast milk volume were 66.33 ± 4.80, 71.30 ± 4.18 and 75.91 ± 6.80 ml; in terms of triglyceride level was 177.84 ± 50.57, 210.72 ± 34.55 and 224.17 ± 12.97 mg/DL, cholesterol level was 14.57 ± 3.70, 21.96 ± 3.82 and 26.26 ± 5.16 mg/DL, albumin concentration was 0.90 ± 0.30, 1.22 ± 0.19 and 1.46 ± 0.28 mg/DL and total protein level was 1.61 ± 0.61, 2.20 ± 0.57 and 2.72 ± 0.30 mg/DL. Finally, the results of ANCOVA analysis for the effects of the intervention, taking into account the baseline values, showed that the intervention was effective and had the greatest effect on cholesterol levels. CONCLUSION: In this small trial, there was a statistically significant association between trial arm and biochemical composition of breastmilk though further studies are needed to see if these changes result in meaningful clinical outcomes to the infant. TRIAL REGISTRATION: IRCT, IRCT20191114045439N1. Registered 14 January 2020- prospective, https://en.irct.ir/trial/43671.

Oncostatic activities of melatonin: Roles in cell cycle, apoptosis, and autophagy.

Melatonin, the major secretory product of the pineal gland, not only regulates circadian rhythms, mood, and sleep but also has actions in neoplastic processes which are being intensively investigated. Melatonin is a promising molecule which considered a differentiating agent in some cancer cells at both physiological and pharmacological concentrations. It can also reduce invasive and metastatic status through receptors MT1 and MT2 cytosolic binding sites, including calmodulin and quinone reductase II enzyme, and nuclear receptors related to orphan members of the superfamily RZR/ROR. Melatonin exerts oncostatic functions in numerous human malignancies. An increasing number of studies report that melatonin reduces the invasiveness of several human cancers such as prostate cancer, breast cancer, liver cancer, oral cancer, lung cancer, ovarian cancer, etc. Moreover, melatonin's oncostatic activities are exerted through different biological processes including antiproliferative actions, stimulation of anti-cancer immunity, modulation of the cell cycle, apoptosis, autophagy, the modulation of oncogene expression, and via antiangiogenic effects. This review focuses on the oncostatic activities of melatonin that targeted cell cycle control, with special attention to its modulatory effects on the key regulators of the cell cycle, apoptosis, and telomerase activity.

CRISPR/Cas9 gene editing: a new approach for overcoming drug resistance in cancer.

The CRISPR/Cas9 system is an RNA-based adaptive immune system in bacteria and archaea. Various studies have shown that it is possible to target a wide range of human genes and treat some human diseases, including cancers, by the CRISPR/Cas9 system. In fact, CRISPR/Cas9 gene editing is one of the most efficient genome manipulation techniques. Studies have shown that CRISPR/Cas9 technology, in addition to having the potential to be used as a new therapeutic approach in the treatment of cancers, can also be used to enhance the effectiveness of existing treatments. Undoubtedly, the issue of drug resistance is one of the main obstacles in the treatment of cancers. Cancer cells resist anticancer drugs by a variety of mechanisms, such as enhancing anticancer drugs efflux, enhancing DNA repair, enhancing stemness, and attenuating apoptosis. Mutations in some proteins of different cellular signaling pathways are associated with these events and drug resistance. Recent studies have shown that the CRISPR/Cas9 technique can be used to target important genes involved in these mechanisms, thereby increasing the effectiveness of anticancer drugs. In this review article, studies related to the applications of this technique in overcoming drug resistance in cancer cells will be reviewed. In addition, we will give a brief overview of the limitations of the CRISP/Cas9 gene-editing technique.

Nitric oxide and inducible nitric oxide synthase levels in EE and NERD patients.

Aim: This article aimed to evaluate nitric oxide (NO) and nitric oxide synthase (iNOS) markers in patients with erosive esophagitis (EE) and those with non-erosive reflux disease (NERD) and compare them with the control group. Background: Gastro-esophageal reflux disease (GERD) is one of the most common disturbances of the upper digestive tract. Inducible nitric oxide synthase (iNOS) is expressed in esophageal adenocarcinoma. NO, the product of this enzyme, has been implicated in the pathogenesis of this condition. Nevertheless, the data on whether iNOS and NO are expressed in the early stages of GERD is conflicting. Methods: In this study, tissue samples were obtained from fifty-four patients (27 with erosive esophagitis and 27 with non-erosive reflux disease) and 27 controls. Tissue concentrations of nitrite, nitrate, and iNOS were measured using Enzyme-Linked Immune-sorbent Assay (ELISA). The Bradford method was used to determine the protein concentration of samples. The results were analyzed by SPSS software (version 22.0). In multiple comparisons, the Tukey test was performed, and p < 0.05 was considered as the level of significance. Results: Tissue amounts of iNOS were significantly higher (p= 0.001) in EE patients compared with the control group. There was a significant difference (p= 0.01) in this factor between EE patients and patients with NERD. Moreover, tissue levels of nitrite and nitrate were significantly higher (p = 0.001) in patient groups compared with the control group. Conclusion: It was observed that NO and iNOS protein were increased in human esophagitis tissue. The results indicated that nitric oxide and iNOS levels are useful and effective markers in the pathogenesis of GERD. While the results are not certain, it is thought that a link exists between the expressions of iNOS and disease progression.

Biochemical Aspects of Scaffolds for Cartilage Tissue Engineering; from Basic Science to Regenerative Medicine.

Chondral defects are frequent and important causes of pain and disability. Cartilage has limited self-repair and regeneration capacity. The ideal approach for articular cartilage defects is the regeneration of hyaline cartilage with sustainable symptom-free constructs. Tissue engineering provides new strategies for the regeneration of functional cartilage tissue through optimized scaffolds with architectural, mechanical, and biochemical properties similar to the native cartilage tissue. In this review, the basic science of cartilage structure, interactions between proteins, stem cells, as well as biomaterials, scaffold characteristics and fabrication methods, as well as current and potential therapies in regenerative medicine will be discussed mostly from a biochemical point of view. Furthermore, the recent trends in scaffold-based therapies and supplementary factors in cartilage tissue engineering will be considered.

The Interaction Network of MicroRNAs with Cytokines and Signaling Pathways in Allergic Asthma.

Allergic asthma is a complicated disease that is affected by many factors. Numerous cytokines and signaling pathways are attributed to the cause of asthma symptoms. MicroRNAs (miRNAs) are a group of small non-coding single-stranded RNA molecules that are involved in gene silencing and posttranscriptional regulation of gene expression by targeting mRNAs. In pathological conditions, altered expression of microRNAs differentially regulates cytokines and signaling pathways and therefore, can be the underlying reason for the pathogenesis of allergic asthma. Indeed, microRNAs participate in airway inflammation via inducing airway structural cells and activating immune responses by targeting cytokines and signaling pathways. Thus, to make a complete understanding of allergic asthma, it is necessary to investigate the communication network of microRNAs with cytokines and signaling pathways which is contributed to the pathogenesis of allergic asthma. Here, we shed light on this aspect of asthma pathology by Summarizing our current knowledge of this topic.

Oncostatic activities of melatonin: Roles in cell cycle, apoptosis, and autophagy.

Melatonin, the major secretory product of the pineal gland, not only regulates circadian rhythms, mood, and sleep but also has actions in neoplastic processes which are being intensively investigated. Melatonin is a promising molecule which considered a differentiating agent in some cancer cells at both physiological and pharmacological concentrations. It can also reduce invasive and metastatic status through receptors MT1 and MT2 cytosolic binding sites, including calmodulin and quinone reductase II enzyme, and nuclear receptors related to orphan members of the superfamily RZR/ROR. Melatonin exerts oncostatic functions in numerous human malignancies. An increasing number of studies report that melatonin reduces the invasiveness of several human cancers such as prostate cancer, breast cancer, liver cancer, oral cancer, lung cancer, ovarian cancer, etc. Moreover, melatonin's oncostatic activities are exerted through different biological processes including antiproliferative actions, stimulation of anti-cancer immunity, modulation of the cell cycle, apoptosis, autophagy, the modulation of oncogene expression, and via antiangiogenic effects. This review focuses on the oncostatic activities of melatonin that targeted cell cycle control, with special attention to its modulatory effects on the key regulators of the cell cycle, apoptosis, and telomerase activity.

MicroRNAs and osteosarcoma: Potential targets for inhibiting metastasis and increasing chemosensitivity.

Osteosarcoma (OS) is the third most common cancer in young adults after lymphoma and brain cancer. Metastasis, like other cellular events, is dependent on signaling pathways; a series of changes in some proteins and signaling pathways pave the way for OS cells to invade and migrate. Ezrin, TGF-ß, Notch, RUNX2, matrix metalloproteinases (MMPs), Wnt/ß-catenin, and phosphoinositide 3-kinase (PI3K)/AKT are among the most important of these proteins and signaling pathways. Despite the improvements in treating OS, the overall survival of patients suffering from the metastatic disease has not experienced any significant change after surgical treatments and chemotherapy and 5-years overall survival in patients with metastatic OS is about 20%. Studies have shown that overexpression or inhibition of some microRNAs (miRNAs) has significant effects in limiting the invasion and migration of OS cells. The results of these studies highlight the potential of the clinical application of some miRNA mimics and miRNA inhibitors (antagomiRs) to inhibit OS metastasis in the future. In addition, some studies have shown that miRNAs are associated with the most important drug resistance mechanisms in OS, and some miRNAs are highly effective targets to increase chemosensitivity. The results of these studies suggest that miRNA mimics and antagomiRs may be helpful to increase the efficacy of conventional chemotherapy drugs in the treatment of metastatic OS. In this article, we discussed the role of various signaling pathways and the involved miRNAs in the metastasis of OS, attempting to provide a comprehensive review of the literature on OS metastasis and chemosensitivity.

From inflammatory bowel disease to colorectal cancer: what's the role of miRNAs?

Inflammatory Bowel Disease (IBD) is a chronic inflammatory disease with relapse and remission periods. Ulcerative colitis and Crohn's disease are two major forms of the disease. IBD imposes a lot of sufferings on the patient and has many consequences; however, the most important is the increased risk of colorectal cancer, especially in patients with Ulcerative colitis. This risk is increased with increasing the duration of disease, thus preventing the progression of IBD to cancer is very important. Therefore, it is necessary to know the details of events contributed to the progression of IBD to cancer. In recent years, the importance of miRNAs as small molecules with 20-22 nucleotides has been recognized in pathophysiology of many diseases, in which IBD and colorectal cancer have not been excluded. As a result, the effectiveness of these small molecules as therapeutic target is hopefully confirmed. This paper has reviewed the related studies and findings about the role of miRNAs in the course of events that promote the progression of IBD to colorectal carcinoma, as well as a review about the effectiveness of some of these miRNAs as therapeutic targets.

Assessment of mucin and alpha-amylase levels in gingival crevicular fluid of chronic periodontitis patients.

BACKGROUND: Chronic periodontitis is the most common form of periodontitis. Several immune and inflammatory factors responsible for periodontal destruction have been found in gingival crevicular fluid (GCF). The current study was conducted to determine the correlation between mucin and alpha-amylase protein values in GCF with chronic periodontitis. METHOD: Forty-five patients with moderate-to-severe chronic periodontitis were selected. Samples of GCF were taken from a specific part of a single root tooth and placed in a closed test tube containing phosphate-buffered saline (PBS) (pH = 7). Sampling was done again after one month. Pre- and post-treatment samples were analyzed for measuring the levels of mucin and alpha-amylase proteins. RESULTS: Paired t test results for these two variables showed that the difference between mucin and alpha-amylase levels before and after treatment is significant. CONCLUSION: The level of both mucin and alpha-amylase in GCF in patients with chronic periodontitis was higher than that of patients who have recovered successfully; and evaluating the values of these two markers could be used to determine the activity of the periodontal disease.

Melatonin: A smart molecule in the DNA repair system.

DNA repair is an important pathway for the protection of DNA molecules from destruction. DNA damage can be produced by oxidative reactive nitrogen or oxygen species, irritation, alkylating agents, depurination and depyrimidination; in this regard, DNA repair pathways can neutralize the negative effects of these factors. Melatonin is a hormone secreted from the pineal gland with an antioxidant effect by binding to oxidative factors. In addition, the effect of melatonin on DNA repair pathways has been proven by the literature. DNA repair is carried out by several mechanisms, of which homologous recombination repair (HRR) and non-homologous end-joining (NHEJ) are of great importance. Because of the importance of DNA repair in DNA integrity and the anticancer effect of this pathway, we presented the effect of melatonin on DNA repair factors regarding previous studies conducted in this area.

Zinc and Respiratory Viral Infections: Important Trace Element in Anti-viral Response and Immune Regulation.

Influenza viruses, respiratory syncytial virus (RSV), and SARS-COV2 are among the most dangerous respiratory viruses. Zinc is one of the essential micronutrients and is very important in the immune system. The aim of this narrative review is to review the most interesting findings about the importance of zinc in the anti-viral immune response in the respiratory tract and defense against influenza, RSV, and SARS-COV2 infections. The most interesting findings on the role of zinc in regulating immunity in the respiratory tract and the relationship between zinc and acute respiratory distress syndrome (ARDS) are reviewed, as well. Besides, current findings regarding the relationship between zinc and the effectiveness of respiratory viruses' vaccines are reviewed. The results of reviewed studies have shown that zinc and some zinc-dependent proteins are involved in anti-viral defense and immune regulation in the respiratory tract. It seems that zinc can reduce the viral titer following influenza infection. Zinc may reduce RSV burden in the lungs. Zinc can be effective in reducing the duration of viral pneumonia symptoms. Zinc may enhance the effectiveness of hydroxychloroquine in reducing mortality rate in COVID-19 patients. Besides, zinc has a positive effect in preventing ARDS and ventilator-induced lung damage. The relationship between zinc levels and the effectiveness of respiratory viruses' vaccines, especially influenza vaccines, is still unclear, and the findings are somewhat contradictory. In conclusion, zinc has anti-viral properties and is important in defending against respiratory viral infections and regulating the immune response in the respiratory tract.