Antioxidant effect of zinc, selenium and their combination on the liver and kidney of alloxan-induced diabetes in rats

Selenium Injection in Dam Rabbits During Gestation Has Important Effects on Progeny Productive Performance

Micromineral elements have a fundamental participation in the processes of organogenesis and fetal development. The objective of this study was to assess the effect of selenium (Se) injection in pregnant female rabbits, during organogenesis or rapid fetal growth, on the productive performance of their progeny. An experiment was carried out with 30 New Zealand female rabbits, with an average age of 6 months. At the end of mating (day 0), using a randomized complete design, the female rabbits were distributed into three experimental groups, which were assigned to the following treatments: Control, female rabbits were injected intramuscularly (IM) with 0.5 ml of saline on days 13 and 23 of gestation; Early administration, female rabbits that were injected IM with Se (0.10 mg/kg BW) on day 13 of gestation (organogenesis) and 0.5 ml of saline on day 23 of gestation; and Late administration, female rabbits that were injected IM with 0.5 ml of saline on day 13 of gestation and Se (0.10 mg/kg BW) on day 23 of gestation (rapid fetal growth). No differences were found on kindling performance of dams and pre-weaning growth of rabbit offspring. However, an injection of Se to pregnant rabbits affected the growth and development of their progeny, with the treatment leading to changes in the yield of some carcass traits (forelimb weight and forelimb muscle weight) and weights of some organs (liver, lungs, and spleen). The Se treatment (both early and late) also resulted in lower concentrations of glucose, triglycerides, and cholesterol when compared to the control group. These effects were different when Se injection was performed during organogenesis or rapid fetal development. The results from this study suggest that there are beneficial effects of gestational Se injection of rabbit dams on important productive traits of their progeny.

Therapeutic Potential and Main Methods of Obtaining Selenium Nanoparticles

This review presents the latest data on the importance of selenium nanoparticles in human health, their use in medicine, and the main known methods of their production by various methods. In recent years, a multifaceted study of nanoscale complexes in medicine, including selenium nanoparticles, has become very important in view of a number of positive features that make it possible to create new drugs based on them or significantly improve the properties of existing drugs. It is known that selenium is an essential trace element that is part of key antioxidant enzymes. In mammals, there are 25 selenoproteins, in which selenium is a key component of the active site. The important role of selenium in human health has been repeatedly proven by several hundred works in the past few decades; in recent years, the study of selenium nanocomplexes has become the focus of researchers. A large amount of accumulated data requires generalization and systematization in order to improve understanding of the key mechanisms and prospects for the use of selenium nanoparticles in medicine, which is the purpose of this review.

The Potential Role of Zinc Oxide Nanoparticles in MicroRNAs Dysregulation in STZ-Induced Type 2 Diabetes in Rats

Diabetes mellitus (DM) is a group of metabolic disorders that are characterized by a loss of glucose homeostasis and insufficiency in production or action of insulin. Development of newly antidiabetic molecules using a variety of organic compounds and biomolecules has been in practice for a long time. Recently, nanomaterials are also being used in antidiabetic studies for their unique properties. In this context, zinc nanoparticles have drawn attention due to the relationship between diabetes and imbalance of zinc homeostasis. Few studies have attempted to investigate the effect of zinc oxide nanoparticles (ZON) in microRNA dysregulations in diabetes. To evaluate the therapeutic effect of ZON on streptozotocin (STZ)-induced diabetic rats as well as its role in microRNA dysregulations. Diabetes was induced in rats by 60 mg/kg body weight (bwt) of STZ and then treated with ZON (5 mg/kg bwt) for 15 consecutive days. The levels of glucose, insulin, oxidative stress markers, and microRNAs expression were measured in liver and pancreas tissues. Intraperitoneal injection of 60 mg/kg bwt of STZ to Wistar rats caused significant decreases in the body weight and Zn contents of pancreas, liver, and kidney. Also, STZ injection increased the blood glucose level and oxidative stress (lipid peroxidation (LPO) and nitric oxide (NO). Meanwhile, STZ decreased blood insulin and pancreatic anti-oxidants. STZ also resulted in β cell dysfunction and destruction and altered the expression of certain pancreatic and liver microRNAs. ZON treatment for 15 days, at a dose of 5 mg/kg bwt resulted in marked improvements in the blood insulin, glucose tolerance, and structure and function of the pancreatic β cells. Furthermore, ZON administration reduced LPO and NO, and increased the levels of enzymatic and non-enzymatic anti-oxidants in STZ-induced diabetic rats. It was found also that ZON specifically regulated the expression of pancreatic and liver microRNAs that involved in diabetes development. The obtained results revealed that ZON is a promising antidiabetic agent. The antidiabetic effect of ZON was partially mediated by restoring the oxidants/antioxidants balance and by modulating the alerted microRNAs.

Hypoglycemic potential of selenium nanoparticles capped with polyvinyl-pyrrolidone in streptozotocin-induced experimental diabetes in rats

This study was aimed to evaluate the efficacy of synthesized selenium nanoparticles (SeNPs) capped with glucose and polyvinyl-pyrrolidone (PVP) on the hyperglycemia and prooxidants/antioxidants imbalance present in model streptozotocin (STZ)-induced diabetic rats. SeNPs were synthesized and characterized. Twenty-four albino male rats were grouped into four different groups. After the rats were induced to have type 2 diabetes by STZ, the SeNPs-treated groups received a dose of 0.5 mg/ml of SeNPs for seven days. Plasma glucose and insulin levels, pancreatic insulin expression, the levels of lipid peroxidation (LPO), nitric oxide (NO), glutathione peroxidase (GPx) and glutathione (GSH) were evaluated. TEM images revealed the formation of semispherical particles with average size between 40 and 50 nm. SeNPs administration successfully reduced the hyperglycemia, raised the levels of insulin in both the pancreas and the plasma and restored the damaged pancreatic tissue. SeNPs also showed enhancement of the elimination of the diabetes-induced oxidative stress injuries by decreasing the pancreatic LPO and NO levels. Furthermore, the activities of the antioxidant enzyme GPx and GSH levels of the diabetic rats were increased. In conclusion, SeNPs capped with PVP could be used in the future as an agent that could manage Diabetes mellitus.

Zinc and selenium combination treatment protected diabetes-induced testicular and epididymal damage in rat

Diabetes increases the possibility of germ cell damage, hypogonadism, and male infertility. Diabetic condition negatively impacts zinc (Zn) and selenium (Se) levels in the body. Zn and Se are among the most important trace elements involved in the regulation of redox reaction, antioxidants enzymes activities, and DNA expression in a germ cell. The present study aimed to elucidate the combined effects of Zn and Se treatment on diabetes-induced germ cell damage in male Sprague Dawley rats. Type 1 diabetes was induced by the single intraperitoneal (i.p.) injection of streptozotocin (55 mg/kg). Zn (3 mg/kg, i.p.) and Se (0.5 mg/kg, i.p.) were administered daily for 8 consecutive weeks. All the animals were provided with normal feed and water throughout the study. The effects on germ cell damage were evaluated by body weight, feed-water intake, organ weight, sperm count, motility, sperm head morphology, biochemical analysis, histology, immunohistochemistry, halo assay, germ cell comet assay, testes terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end-labeling (TUNEL) assay, sperm TUNEL assay, serum protein pattern analysis, and subcellular analysis using transmission electron microscopy. Further, the expressions of nuclear erythroid-derived related factor 2, catalase, glutathione peroxidase 4, and glutathione peroxidase 5 were carried out to ascertain the mechanism of protection. The present results demonstrated that 8 weeks combined treatment of Zn (3 mg/kg, i.p.) and Se (0.5 mg/kg, i.p.) reduced diabetes-induced germ cell damage. This study further highlighted that Zn and Se combination treatment might be a better strategy for the germ cell protection in diabetes and deserve further investigation.

The current and future perspectives of zinc oxide nanoparticles in the treatment of diabetes mellitus

Diabetes mellitus (DM) is a multifaceted and costly disease, which requires serious attention. Finding a cheaper anti-diabetic alternative that can act on multiple disease-related targets and pathways is the ultimate treatment goal for DM. Nanotechnology has offered some exciting possibilities in biomedical and drug delivery applications. Zinc oxide nanoparticles (ZnO-NPs), a novel agent to deliver zinc, have great implications in many disease therapies including DM. This review summarizes the pharmacological mechanisms by which ZnO-NPs alleviate DM and diabetic complications. Research implications and future perspectives were also discussed.

Comparative study of cardio-protective effects of zinc oxide nanoparticles and zinc sulfate in streptozotocin-induced diabetic rats

The cardio-protective effects of zinc oxide nanoparticles (Zn NPs) against diabetes-induced cardiopathy were evaluated and compared with zinc sulfate (ZnSO₄). A total of 120 Wistar rats were randomly categorized as healthy and diabetic groups. Then, the 2 groups were classified in 5 subgroups. The animals received oral supplementations containing different Zn NP (ie, doses of 1, 3, and 10mg/kg) and ZnSO₄ (30mg/kg) concentrations over 8 weeks. Blood and cardiac tissue samples were collected in the different time intervals and subjected to biochemical and histopathological analysis. Zn NPs showed dual effects, as its middle dose played protective role and recovered cardiac damages evidenced by significant reduction of serum cholesterol, HDL-cholesterol, lipoprotein (a), atherogenic index, TNF-α, cardiac MDA, B-type natriuretic peptide and caspase-3 activity. Apoptosis indices and histopathological features also were improved. However, the highest dose was found to be toxic and resulted in aggravation of the injuries. Another interesting finding is the ability of the higher doses of Zn-NPs (3 and 10mg/kg) to elevate cardiac zinc levels above the normal range in healthy animal. ZnSO₄ also helped to recuperation of the damages, but the middle dose of Zn NPs was more efficient as compared to ZnSO₄. Conclusively, Zn NPs have the potential for Zn delivery in diabetic patients.

Selenium levels and Glutathione peroxidase activity in the plasma of patients with type II diabetes mellitus

Selenium, an essential trace element, is involved in the complex system of defense against oxidative stress through selenium-dependent glutathione peroxidases (GPx) and other selenoproteins. Because of its antioxidant properties, selenium or its selenospecies at appropriate levels could hinder oxidative stress and so development of diabetes. In this vein, quantitative speciation of selenium in human plasma samples from healthy and diabetic patients (controlled and non-controlled) was carried out by affinity chromatography (AF) coupled on-line to inductively coupled plasma mass spectrometry (ICP-MS) and isotope dilution analysis (IDA). Similarly, it is well known that patients with diabetes who exhibit poor control of blood glucose show a decreased total antioxidant activity. Thus, we evaluated the enzymatic activity of GPx in diabetic and healthy individuals, using the Paglia and Valentine enzymatic method, observing a significant difference (p<0.05) between the three groups of assayed patients (healthy (n=24): 0.61±0.11U/ml, controlled diabetic (n=38): 0.40±0.12U/ml and non-controlled diabetic patients (n=40): 0.32±0.09U/ml). Our results show that hyperglycemia induces oxidative stress in diabetic patients compared with healthy controls. What is more, glycation of GPx experiments demonstrated that it is the degree of glycation of the selenoenzyme (another species of the Se protein) what actually modulates its eventual activity against ROS in type II diabetes mellitus patients.

Comparative Study of Antidiabetic Activity and Oxidative Stress Induced by Zinc Oxide Nanoparticles and Zinc Sulfate in Diabetic Rats

In the current study, antidiabetic activity and toxic effects of zinc oxide nanoparticles (ZnO) were investigated in diabetic rats compared to zinc sulfate (ZnSO4) with particular emphasis on oxidative stress parameters. One hundred and twenty male Wistar rats were divided into two healthy and diabetic groups, randomly. Each major group was further subdivided into five subgroups and then orally supplemented with various doses of ZnO (1, 3, and 10 mg/kg) and ZnSO4 (30 mg/kg) for 56 consecutive days. ZnO showed greater antidiabetic activity compared to ZnSO4 evidenced by improved glucose disposal, insulin levels, and zinc status. The altered activities of erythrocyte antioxidant enzymes as well as raised levels of lipid peroxidation and a marked reduction of total antioxidant capacity were observed in rats receiving ZnO. ZnO nanoparticles acted as a potent antidiabetic agent, however, severely elicited oxidative stress particularly at higher doses.

In vitro studies on the pleotropic antidiabetic effects of zinc oxide nanoparticles

Aim: Our earlier study demonstrated antidiabetic activity of zinc oxide nanoparticles (ZON) in diabetic rats. The present study was performed to elucidate its mechanism of antidiabetic action. Methods: Protein tyrosine phosphatase 1B, protein kinase B and hormone sensitive lipase phosphorylation; glucose transporter 4 translocation and glucose uptake; glucose 6 phosphatase, phosphoenol pyruvate carboxykinase and glucokinase expression; and pancreatic beta cell proliferation were evaluated after ZON treatment to cells. Result: ZON treatment resulted in PKB activation, protein tyrosine phosphatase 1B inactivation, increased glucose transporter 4 translocation and enhanced glucose uptake, decreased glucose 6 phosphatase and phosphoenol pyruvate carboxykinase expression, hormone sensitive lipase inactivation and pancreatic beta cell proliferation. Conclusion: To the best of our knowledge, we report for the first time, pleiotropic antidiabetic effects of ZON viz. improved insulin signaling, enhanced glucose uptake, decreased hepatic glucose output, decreased lipolysis and enhanced pancreatic beta cell mass.

Ameliorative Effect of Zinc Oxide Nanoparticles on Antioxidants and Sperm Characteristics in Streptozotocin-Induced Diabetic Rat Testes

The present study investigated the impact of zinc oxide nanoparticles (ZnONPs) on the oxidative status and sperm characteristics in diabetic rat testicular tissue. Forty male albino rats were used in this study; 10 of them served as a control and 30 rats were injected with a single dose (100 mg/kg) of streptozotocin intraperitoneally. They were subdivided into diabetic, diabetic + ZnONPs (10 mg/kg B.W.), and diabetic and cotreated with ZnONPs + insulin groups. The sperm count and motility were assessed. The activity and mRNA expression of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GRD), and Glutathion-S-Transferase (GST) were determined in the testicular tissue. Malondialdehyde (MDA) and reduced glutathione (GSH) levels were estimated in the testicular tissue. Sperm count and motility increased in ZnONPs treated diabetic rats. A significant increase in the activity and mRNA expression of SOD, CAT, GPx, GRD, and GST was shown in ZnONPs treated diabetic rats. MDA significantly decreased, while GSH increased in testicular tissue of ZnONPs treated diabetic rats. It was concluded that ZnONPs either alone or in combination with insulin have the ability to increase the sperm count and motility and protect the testicular tissue against the oxidative stress induced by diabetes in rats.

Jasada bhasma, a Zinc-Based Ayurvedic Preparation: Contemporary Evidence of Antidiabetic Activity Inspires Development of a Nanomedicine

The roles of metals in human physiology are well established. It is also known that many metals are required in trace amounts for normal metabolism and their deficiency leads to diseases. In Ayurveda, metal-based preparations, that is, bhasmas, are indicated for the treatment of several diseases. Standard textbooks of Ayurveda recommend Jasada bhasma (zinc based bhasma) as the treatment of choice for diabetes. Modern medicine also recognizes the important role of zinc in glucose homeostasis. Yet, studies that validate the use of Jasada bhasma are few and uncomprehensive. There is an imminent need for a systematic study on physicochemical characterization, pharmacological efficacy, and toxicity assessment of several bhasma preparations to generate scientific evidence of their utility and safety. Interestingly, recent studies suggest that bhasmas comprise submicronic particles or nanoparticles. Thus a bhasma-inspired new drug discovery approach could emerge in which several metal based nanomedicines could be developed. This would help in utilizing the age old, time-tested wisdom of Ayurveda in modern medicine. One such study on antidiabetic activity of Jasada bhasma and the corresponding new drug, namely, zinc oxide nanoparticles, is briefly discussed, as an example.

Antidiabetic activity of zinc oxide and silver nanoparticles on streptozotocin-induced diabetic rats

The use of nanoparticles in medicine is an attractive proposition. In the present study, zinc oxide and silver nanoparticles were evaluated for their antidiabetic activity. Fifty male albino rats with weight 120 ± 20 and age 6 months were used. Animals were grouped as follows: control; did not receive any type of treatment, diabetic; received a single intraperitoneal dose of streptozotocin (100 mg/kg), diabetic + zinc oxide nanoparticles (ZnONPs), received single daily oral dose of 10 mg/kg ZnONPs in suspension, diabetic + silver nanoparticles (SNPs); received a single daily oral dose of SNP of 10 mg/kg in suspension and diabetic + insulin; received a single subcutaneous dose of 0.6 units/50 g body weight. Zinc oxide and silver nanoparticles induce a significant reduced blood glucose, higher serum insulin, higher glucokinase activity higher expression level of insulin, insulin receptor, GLUT-2 and glucokinase genes in diabetic rats treated with zinc oxide, silver nanoparticles and insulin. In conclusion, zinc oxide and sliver nanoparticles act as potent antidiabetic agents.

Zinc oxide nanoparticles show antidiabetic activity in streptozotocin-induced Type 1 and 2 diabetic rats

Aim: The correlation of diabetes and an imbalance in zinc homeostasis makes zinc-based therapy an attractive proposition. In this study, zinc oxide nanoparticles were evaluated for antidiabetic effects and safety. Materials & methods: Zinc oxide nanoparticles (1, 3 and 10 mg/kg) were tested for antidiabetic activity in streptozotocin-induced Type 1 and 2 diabetic rats. A single-dose pharmacokinetic study, cytotoxicity, hemolysis, acute and subacute toxicity tests, and mechanism-of-action studies were performed. Results: Oral administration of zinc oxide nanoparticles resulted in significant antidiabetic effects – that is, improved glucose tolerance, higher serum insulin (70%), reduced blood glucose (29%), reduced nonesterified fatty acids (40%) and reduced triglycerides (48%). Nanoparticles were systemically absorbed resulting in elevated zinc levels in the liver, adipose tissue and pancreas. Increased insulin secretion and superoxide dismutase activity were also seen in rat insulinoma (RIN-5F) cells. Nanoparticles were safe up to a 300 mg/kg dose in rats. Conclusion: Zinc oxide nanoparticles are a promising antidiabetic agent warranting further studies.

Original submitted 9 July 2012; Revised submitted 27 November 2012; Published online 21 February 2013