Melatonin: New insights on its therapeutic properties in diabetic complications

Diabetes and diabetic complications are considered as leading causes of both morbidity and mortality in the world. Unfortunately, routine medical treatments used for affected patients possess undesirable side effects, including kidney and liver damages as well as gastrointestinal adverse reactions. Therefore, exploring the novel therapeutic strategies for diabetic patients is a crucial issue. It has been recently shown that melatonin, as main product of the pineal gland, despite its various pharmacological features including anticancer, anti-Aging, antioxidant and anti-inflammatory effects, exerts anti-diabetic properties through regulating various cellular mechanisms. The aim of the present review is to describe potential roles of melatonin in the treatment of diabetes and its complications. © 2020 The Author(s)

Clinical Application of Melatonin in the Treatment of Cardiovascular Diseases: Current Evidence and New Insights into the Cardioprotective and Cardiotherapeutic Properties

Cardiovascular diseases (CVDs) are the leading global cause of mortality and disability, tending to happen in younger individuals in developed countries. Despite improvements in medical treatments, the therapy and long-term prognosis of CVDs such as myocardial ischemia�reperfusion, atherosclerosis, heart failure, cardiac hypertrophy and remodeling, cardiomyopathy, coronary artery disease, myocardial infarction, and other CVDs threatening human life are not satisfactory enough. Therefore, many researchers are attempting to identify novel potential therapeutic methods for the treatment of CVDs. Melatonin is an anti-inflammatory and antioxidant agent with a wide range of therapeutic properties. Recently, several investigations have been carried out to evaluate its effectiveness and efficiency in CVDs therapy, focusing on mechanistic pathways. Herein, this review aims to summarize current findings of melatonin treatment for CVDs. © 2020, Springer Science+Business Media, LLC, part of Springer Nature

Therapeutic application of nutraceuticals in diabetic nephropathy: Current evidence and future implications

Diabetes mellitus (DM) is a common metabolic disease which may cause several complications, such as diabetic nephropathy (DN). The routine medical treatments used for DM are not effective enough and have many undesirable side effects. Moreover, the global increased prevalence of DM makes researchers try to explore potential complementary or alternative treatments. Nutraceuticals, as natural products with pharmaceutical agents, have a wide range of therapeutic properties in various pathologic conditions such as DN. However, the exact underlying mechanisms have not been fully understood. The purpose of this review is to summarize recent findings on the effect of nutraceuticals on DN. © 2020 John Wiley & Sons Lt

Determination of vanillin in different food samples by using SMM/Au@ZIF-67 electrochemical sensor

Abstract Vanillin is a popular flavoring agent in many food products. Simple, fast, and reliable quantification of this compound is crucial for the food industry. In this work, we have developed a new electrochemical sensor for accurate detection of vanillin in various real samples. The composite electrode was made of sodium montmorillonite nanoclay (SMM) and gold nanoparticles modified ZIF-67 (Au@ZIF-67), in which SMM contributes to the large adsorption capacity of the analyte, ZIF-67 and SMM supply more sensing active sites, and gold nanoparticles provide high electrical conductivity. The sensing electrode was comprehensively characterized using Brunauer–Emmett–Teller, EDS, XRD, SEM, FTIR, and TEM, and its electrochemical behavior for determination of vanillin including the electrooxidation mechanism of vanillin and different parameters such as scan rate and pH value was investigated. The result revealed that a two electron-two proton process was involved in the electrooxidation of vanillin, which takes place more readily due to the lower potential on the surface of SMM/Au@ZIF-67/carbon paste electrode. The new composite electrode was also more sensitive to vanillin detection with an anodic peak current almost 2.6 times more than that of the bare electrode. A linear sensing concentration range was established between 1 and 1200 nM with a detection limit of 0. 3 nM and a limit of quantitation of 1 nM. For real samples, the sensor demonstrated excellent recovery rates and reliability that was comparable to the standard high-performance liquid chromatography method

Silver ion imprinted polymer nanobeads based on a mixed aza-thioether crown containing a 1,10-phenanthroline subunit for solid phase extraction and for voltammetric and potentiometric silver sensors

A new nano-sized silver(I) ion-imprinted polymer (IIP) was prepared via precipitation copolymerization using ethyleneglycol dimethacrylate, as a cross-linking agent in the presence of Ag+ and an aza-thioether crown containing a 1,10-phenanthroline subunit as a highly selective complexing agent. The imprint silver(I) ion was removed from the polymeric matrix using a 1.0 M HNO3 solution. The resulting powder material was characterized using IR spectroscopy and scanning electron microscopy. The SEM micrographs showed colloidal nanoparticles of about 52 nm and 75 nm in diameter and slightly irregular in shape for leached and unleached IIPs, respectively. The optimal pH for quantitative enrichment was 6.0 and maximum sorbent capacity of the prepared IIP for Ag+ was 18.08 mmol g-1. The relative standard deviation and limit of detection (LOD = 3Sb/m) for flame atomic absorption spectrometric determination of silver(I) ion, after its selective extraction by the prepared IIP nanobeads, were evaluated as 2.42% and 2.2 10-8 M, respectively. The new Ag+-IIP was also applied as a suitable sensing element to the preparation of highly selective and sensitive voltammetric and potentiometric sensors for ultra trace detection of silver(I) ion in water samples, with low limits of detection

Melatonin and morphine: potential beneficial effects of co-use

Morphine is a potent analgesic agent used to control acute or chronic pain. Chronic administration of morphine results in analgesic tolerance, hyperalgesia, and other side effects including dependence, addiction, respiratory depression, and constipation, which limit its clinical usage. Therefore, identifying the new analgesics with fewer side effects which could increase the effect of morphine and reduce its side effects is crucial. Melatonin, a multifunctional molecule produced in the body, is known to play an important role in pain regulation. The strong anti-inflammatory effect of melatonin is suggested to be involved in the attenuation of the pain associated with inflammation. Melatonin also increases the anti-nociceptive actions of opioids, such as morphine, and reverses their tolerance through regulating several cellular signaling pathways. In this review, published articles evaluating the effect of the co-consumption of melatonin and morphine in different conditions were investigated. Our results show that melatonin has pain-killing properties when administered alone or in combination with other anti-nociceptive drugs. Melatonin decreases morphine consumption in different pathologies. Furthermore, attenuation of morphine intake can be accompanied by reduction of morphine-associated side-effects, including physical dependence, morphine tolerance, and morphine-related hyperalgesia. Therefore, it is reasonable to believe that the combination of melatonin with morphine could reduce morphine-induced tolerance and hyperalgesia, which may result from anti-inflammatory and antioxidant properties of melatonin. Overall, we underscore that, to further ameliorate patients' life quality and control their pain in various pathological conditions, melatonin deserves to be used with morphine by anesthesiologists in clinical practice. © 2020 Société Française de Pharmacologie et de Thérapeutique

Melatonin and morphine: potential beneficial effects of co-use

Morphine is a potent analgesic agent used to control acute or chronic pain. Chronic administration of morphine results in analgesic tolerance, hyperalgesia, and other side effects including dependence, addiction, respiratory depression, and constipation, which limit its clinical usage. Therefore, identifying the new analgesics with fewer side effects which could increase the effect of morphine and reduce its side effects is crucial. Melatonin, a multifunctional molecule produced in the body, is known to play an important role in pain regulation. The strong anti-inflammatory effect of melatonin is suggested to be involved in the attenuation of the pain associated with inflammation. Melatonin also increases the anti-nociceptive actions of opioids, such as morphine, and reverses their tolerance through regulating several cellular signaling pathways. In this review, published articles evaluating the effect of the co-consumption of melatonin and morphine in different conditions were investigated. Our results show that melatonin has pain-killing properties when administered alone or in combination with other anti-nociceptive drugs. Melatonin decreases morphine consumption in different pathologies. Furthermore, attenuation of morphine intake can be accompanied by reduction of morphine-associated side-effects, including physical dependence, morphine tolerance, and morphine-related hyperalgesia. Therefore, it is reasonable to believe that the combination of melatonin with morphine could reduce morphine-induced tolerance and hyperalgesia, which may result from anti-inflammatory and antioxidant properties of melatonin. Overall, we underscore that, to further ameliorate patients' life quality and control their pain in various pathological conditions, melatonin deserves to be used with morphine by anesthesiologists in clinical practice. © 2020 Société Française de Pharmacologie et de Thérapeutique

Diabetic retinopathy pathogenesis and the ameliorating effects of melatonin; involvement of autophagy, inflammation and oxidative stress

Diabetic retinopathy (DR), a microvascular complication of diabetes mellitus (DM), remains as one of the major causes of vision loss worldwide. The release of pro-inflammatory cytokines and the adhesion of leukocytes to retinal capillaries are initial events in DR development. Inflammation, ER stress, oxidative stress and autophagy are major causative factors involved in the pathogenesis of DR. Diabetes associated hyperglycemia leads to mitochondrial electron transport chain dysfunction culminating in a rise in ROS generation. Since mitochondria are the major source of ROS production, oxidative stress induced by mitochondrial dysfunction also contributes to the development of diabetic retinopathy. Autophagy increases in the retina of diabetic patients and is regulated by ER stress, oxidative stress and inflammation-related pathways. Autophagy functions as a double-edged sword in DR. Under mild stress, autophagic activity can lead to cell survival while during severe stress, dysregulated autophagy results in massive cell death and may have a role in initiation and exacerbation of DR. Melatonin and its metabolites play protective roles against inflammation, ER stress and oxidative stress due to their direct free radical scavenger activities and indirect antioxidant activity via the stimulation antioxidant enzymes including glutathione reductase, glutathione peroxidase, superoxide dismutase and catalase. Melatonin also acts as a cell survival agent by modulating autophagy in various cell types and under different conditions through amelioration of oxidative stress, ER stress and inflammation. Herein, we review the possible effects of melatonin on diabetic retinopathy, focusing on its ability to regulate autophagy processes. © 201