Diosmin, a Citrus Nutrient, Activates Imidazoline Receptors to Alleviate Blood Glucose and Lipids in Type 1-Like Diabetic Rats

Fabrication of diosmin loaded food-grade bilayer nanoparticles with modified chitosan and soy peptides and antioxidant properties examination

Diosmin is a flavonoid derived from plants, possessing anti-inflammatory, antioxidant, antidiabetic, neuroprotective and cardiovascular protective properties. However, diosmin has low solubility in water, leading to low bioavailability. In this study, we constructed bilayer nanoparticles with trimethyl chitosan and soy peptides to improve the oral bioaccessibility and bioavailability of diosmin, and determined the characteristics and antioxidant properties of the diosmin-loaded nanoparticles. The results showed that the size of the nanoparticles was around 250 nm with the encapsulation efficiency higher than 97 %, and the nanoparticles were stable under regular conditions. In vitro digestion suggested the nanoparticles could protect diosmin from releasing in gastric digestion but promote the bioaccessibility of diosmin in intestine. Furthermore, the diosmin-loaded nanoparticles presented excellent antioxidant activities in vitro and significantly decreased the Lipopolysaccharides-induced brain Malondialdehyde (MDA) level by oral administration. Therefore, the reported nanoparticles may be an effective platform for improving the oral bioavailability of diosmin.

Thymoquinone activates imidazoline receptor to enhance glucagon-like peptide-1 secretion in diabetic rats

INTRODUCTION

Thymoquinone (TQ) is one of the principal bioactive ingredients proven to exhibit anti-diabetic effects. Recently, glucagon-like peptide-1 (GLP-1) has been found to be involved in antidiabetic effects in rats. The aim of this study was to evaluate the mediation of GLP-1 in the antidiabetic effect of TQ and to understand the possible mechanisms.

MATERIAL AND METHODS

NCI-H716 cells and CHO-K1 cells were used to investigate the effects of TQ on GLP-1 secretion in vitro. In type 1 diabetic rats, the changes in plasma glucose and GLP-1 levels were evaluated with TQ treatment.

RESULTS

The direct effect of TQ on imidazoline receptors (I-Rs) was identified in CHO-K1 cells overexpressing I-Rs. Additionally, in the intestinal NCI-H716 cells that may secrete GLP-1, TQ treatment enhanced GLP-1 secretion in a dose-dependent manner. However, these effects of TQ were reduced by ablation of I-Rs with siRNA in NCI-H716 cells. Moreover, these effects were inhibited by BU224, the imidazoline I2 receptor (I-2R) antagonist. In diabetic rats, TQ increased plasma GLP-1 levels, which were inhibited by BU-224 treatment. Functionally, TQ-attenuated hyperglycemia is also evidenced through GLP-1 using pharmacological manipulations.

CONCLUSIONS

This report demonstrates that TQ may promote GLP-1 secretion through I-R activation to reduce hyperglycemia in type-1 diabetic rats.

Pharmacologically Active Phytomolecules Isolated from Traditional Antidiabetic Plants and Their Therapeutic Role for the Management of Diabetes Mellitus

Diabetes mellitus is a chronic complication that affects people of all ages. The increased prevalence of diabetes worldwide has led to the development of several synthetic drugs to tackle this health problem. Such drugs, although effective as antihyperglycemic agents, are accompanied by various side effects, costly, and inaccessible to the majority of people living in underdeveloped countries. Medicinal plants have been used traditionally throughout the ages to treat various ailments due to their availability and safe nature. Medicinal plants are a rich source of phytochemicals that possess several health benefits. As diabetes continues to become prevalent, health care practitioners are considering plant-based medicines as a potential source of antidiabetic drugs due to their high potency and fewer side effects. To better understand the mechanism of action of medicinal plants, their active phytoconstituents are being isolated and investigated thoroughly. In this review article, we have focused on pharmacologically active phytomolecules isolated from medicinal plants presenting antidiabetic activity and the role they play in the treatment and management of diabetes. These natural compounds may represent as good candidates for a novel therapeutic approach and/or effective and alternative therapies for diabetes.

Multidimensional in silico strategy for identification of natural polyphenols-based SARS-CoV-2 main protease (Mpro) inhibitors to unveil a hope against COVID-19

SARS-CoV-2, a rapidly spreading new strain of human coronavirus, has affected almost all the countries around the world. The lack of specific drugs against SARS-CoV-2 is a significant hurdle towards the successful treatment of COVID-19. Thus, there is an urgent need to boost up research for the development of effective therapeutics against COVID-19. In the current study, we investigated the efficacy of 81 medicinal plant-based bioactive compounds against SARS-CoV-2 M^pro by using various in silico techniques. The interaction affinities of polyphenolic compounds towards SARS-CoV-2 M^pro was assessed via intramolecular (by Quantum Mechanic), intermolecular (by Molecular Docking), and spatial (by Molecular Dynamic) simulations. Our obtained result demonstrate that Hesperidin, rutin, diosmin, and apiin are most effective compounds agents against SARS-CoV-2 Mpro as compared to Nelfinavir (positive control). This study will hopefully pave a way for advanced experimental research to evaluate the in vitro and in vivo efficacy of these compounds for the treatment of COVID-19.

Short-Term Effects of Supplemental L-Arginine, Diosmin, Troxerutin, and Hesperidin in Diabetic Patients: A Pilot Study

Background and Aims

Inflammatory, oxidative stress, and endothelial dysfunction play a key role in the pathogenesis of long-term cardiovascular complications in patients with diabetes. The present observational prospective study is aimed at evaluating the effects of micronutrients and phytochemicals contained in the dietary supplement Flebotrofine® (AMNOL Chimica Biologica) on biochemical markers of inflammation, endothelial dysfunction, and glycemic control in patients with diabetes.

Methods

105 type 1 or type 2 diabetes patients regularly took a daily dose of the dietary supplement Flebotrofine® for three consecutive months, and haematological and biochemical parameters were checked at baseline, after three months of treatment, and one month after its suspension. Statistical comparison of the laboratory parameters was performed using the two-tailed ANOVA test for repeated samples with a statistical significance level set at p < 0.05.

Results

The daily use of Flebotrofine® did not change the glycemic metabolic compensation of enrolled patients. After three months of regular Flebotrofine® intake, the plasma levels of the antioxidant β-carotene and of arginine were significantly higher compared with the baseline values, with a decrease in the ADMA/arginine ratio. In contrast, apolipoprotein B, ApoB/ApoA1 ratio, and platelet and leukocyte counts significantly dropped.

Conclusion

The daily use of Flebotrofine® might be a valid supplement of arginine, the precursor of NO, and essential in the prevention of endothelial dysfunction. The regular intake of arginine and phytochemicals also improved the antioxidant and antithrombotic profile of enrolled patients. Therefore, Flebotrofine® could be a useful dietary supplement to prevent long-term complications in patients with diabetes.

Omnifarious fruit polyphenols: an omnipotent strategy to prevent and intervene diabetes and related complication?

Diabetes mellitus is a metabolic syndrome which cannot be cured. Recently, considerable interest has been focused on food ingredients to prevent and intervene in complications of diabetes. Polyphenolic compounds are one of the bioactive phytochemical constituents with various biological activities, which have drawn increasing interest in human health. Fruits are part of the polyphenol sources in daily food consumption. Fruit-derived polyphenols possess the anti-diabetic activity that has already been proved either from in vitro studies or in vivo studies. The mechanisms of fruit polyphenols in treating diabetes and related complications are under discussion. This is a comprehensive review on polyphenols from the edible parts of fruits, including those from citrus, berries, apples, cherries, mangoes, mangosteens, pomegranates, and other fruits regarding their potential benefits in preventing and treating diabetes mellitus. The signal pathways of characteristic polyphenols derived from fruits in reducing high blood glucose and intervening hyperglycemia-induced diabetic complications were summarized.

Diosmin attenuates schizophrenia-like behavior, oxidative stress, and acetylcholinesterase activity in mice

OBJECTIVES

Diosmin (DSM), commonly isolated from various plants, is a citrus nutrient that has been shown to increase intracellular antioxidant capacity and assuage symptoms associated with neurological disorders. Deficiency in the antioxidant system has been implicated in the pathogenesis of schizophrenia. The use of antioxidants as neuroprotectants to suppress schizophrenia pathology is increasingly being sought. Hence, this study investigated the effects of DSM on schizophrenia-like behavior and the underlying changes in biomarkers of oxidative stress and acetylcholinesterase (AChE) activity in mice.

METHODS

The acute antipsychotic effect of DSM (25, 50, and 100 mg/kg, intraperitoneally [i.p.]), haloperidol (1 mg/kg, i.p.), and risperidone (RIS) (0.5 mg/kg, i.p.) was investigated on stereotyped behaviors induced by apomorphine (2 mg/kg, i.p.) and ketamine (10 mg/kg, i.p.). The effect of DSM on ketamine-induced hyperlocomotion, immobility enhancement, and its woodblock cataleptogenic potential was evaluated. Also, the subacute antipsychotic potential of DSM was assessed following intraperitoneal injection of DSM (25-100 mg/kg, i.p.) alone and in combination with ketamine (20 mg/kg, i.p.) for 10 days. The behaviors of the animals were assessed in the open-field, Y-maze, and forced swim tests. Brains of the animals were afterward processed for spectrophotometric assay of oxidative stress and AChE contents.

RESULTS

DSM (25, 50, and 100 mg/kg) attenuated apormorphine-induced stereotypy and devoid of cataleptogenic effect. DSM and RIS reversed acute and subacute ketamine-induced schizophrenia-like behaviors. Disomin alone increased cognitive function and reduced despair-like phenotype. Furthermore, DSM increased superoxide dismutase and glutathione and decreased malondialdehyde and AChE levels in naïve and ketamine schizophrenic mice.

CONCLUSIONS

DSM prevents schizophrenia-like behavior, attenuates oxidative stress, and AChE activity in naïve and ketamine schizophrenic mice.

Diosmin attenuates schizophrenia-like behavior, oxidative stress, and acetylcholinesterase activity in mice

Objectives Diosmin (DSM), commonly isolated from various plants, is a citrus nutrient that has been shown to increase intracellular antioxidant capacity and assuage symptoms associated with neurological disorders. Deficiency in the antioxidant system has been implicated in the pathogenesis of schizophrenia. The use of antioxidants as neuroprotectants to suppress schizophrenia pathology is increasingly being sought. Hence, this study investigated the effects of DSM on schizophrenia-like behavior and the underlying changes in biomarkers of oxidative stress and acetylcholinesterase (AChE) activity in mice. Methods The acute antipsychotic effect of DSM (25, 50, and 100 mg/kg, intraperitoneally [i.p.]), haloperidol (1 mg/kg, i.p.), and risperidone (RIS) (0.5 mg/kg, i.p.) was investigated on stereotyped behaviors induced by apomorphine (2 mg/kg, i.p.) and ketamine (10 mg/kg, i.p.). The effect of DSM on ketamine-induced hyperlocomotion, immobility enhancement, and its woodblock cataleptogenic potential was evaluated. Also, the subacute antipsychotic potential of DSM was assessed following intraperitoneal injection of DSM (25-100 mg/kg, i.p.) alone and in combination with ketamine (20 mg/kg, i.p.) for 10 days. The behaviors of the animals were assessed in the open-field, Y-maze, and forced swim tests. Brains of the animals were afterward processed for spectrophotometric assay of oxidative stress and AChE contents. Results DSM (25, 50, and 100 mg/kg) attenuated apormorphine-induced stereotypy and devoid of cataleptogenic effect. DSM and RIS reversed acute and subacute ketamine-induced schizophrenia-like behaviors. Disomin alone increased cognitive function and reduced despair-like phenotype. Furthermore, DSM increased superoxide dismutase and glutathione and decreased malondialdehyde and AChE levels in naïve and ketamine schizophrenic mice. Conclusions DSM prevents schizophrenia-like behavior, attenuates oxidative stress, and AChE activity in naïve and ketamine schizophrenic mice.

Citrus Flavonoids as Promising Phytochemicals Targeting Diabetes and Related Complications: A Systematic Review of In Vitro and In Vivo Studies

The consumption of plant-based food is important for health promotion, especially concerning the prevention and management of chronic diseases. Flavonoids are the main bioactive compounds in citrus fruits, with multiple beneficial effects, especially antidiabetic effects. We systematically review the potential antidiabetic action and molecular mechanisms of citrus flavonoids based on in vitro and in vivo studies. A search of the PubMed, EMBASE, Scopus, and Web of Science Core Collection databases for articles published since 2010 was carried out using the keywords citrus, flavonoid, and diabetes. All articles identified were analyzed, and data were extracted using a standardized form. The search identified 38 articles, which reported that 19 citrus flavonoids, including 8-prenylnaringenin, cosmosiin, didymin, diosmin, hesperetin, hesperidin, isosiennsetin, naringenin, naringin, neohesperidin, nobiletin, poncirin, quercetin, rhoifolin, rutin, sineesytin, sudachitin, tangeretin, and xanthohumol, have antidiabetic potential. These flavonoids regulated biomarkers of glycemic control, lipid profiles, renal function, hepatic enzymes, and antioxidant enzymes, and modulated signaling pathways related to glucose uptake and insulin sensitivity that are involved in the pathogenesis of diabetes and its related complications. Citrus flavonoids, therefore, are promising antidiabetic candidates, while their antidiabetic effects remain to be verified in forthcoming human studies.

Endogenous opiates and behavior: 2017

This paper is the fortieth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2017 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug abuse and alcohol (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Metabolism and pharmacological activities of the natural health-benefiting compound diosmin

Diosmin is a famous natural flavonoid for treating chronic venous insufficiency and varicose veins.

Dietary plant flavonoids in prevention of obesity and diabetes

Obesity and diabetes are the most prevailing chronic metabolic diseases worldwide from mainly lipid and glucose metabolic dysfunctions and their incidence is increasing at an alarming high rate. Obesity is characterized by excess fat accumulation in WAT and liver and is the central player of insulin resistance in the peripheral tissues from chronic inflammation, lipotoxicity and gut dysbiosis, and plays a key role for development of type 2 diabetes (T2DM) and vascular diseases. Diabetes mellitus, known as diabetes, is chiefly characterized by hyperglycaemia from impaired insulin secretion and insulin resistance. Several identified mutant genes in insulin secretion and resistance and various environmental factors are considered responsible for the onset of this disease. Currently available oral synthetic drugs, biguanides, incretin mimetic, GLP-1R and PPAR agonists and DPP-4 inhibitors for management of obesity and diabetes have several adverse effects in patients on long-term use. Emerging evidence supports the efficacy of dietary plant flavonoids in prevention and attenuation of obesity and diabetes by the protection and proliferation of pancreatic beta-cells and improvement of their insulin secretory function via activation of cAMP/PKA signaling pathway as well as in the improvement of insulin sensitivity in the peripheral metabolic tisssues for glucose uptake and utilization via inhibition of inflammation, lipotoxicity and oxidative stress. These flavonoids improve GLUT-4 expression and translocation to plasma membrane by activation of insulin-sensitive PI3K/Akt signaling and insulin-independent AMPK, SIRT-1 and MOR activation pathways for regulation of glucose homeostasis, and improve fat oxidation and reduce lipid synthesis by regulation of related genes for lipid homeostasis in the body of obese diabetic animals. In this chapter, we have highlighted all these beneficial anti-obesity and antidiabetic potentials of some dietary plant flavonoids along with their molecular actions, bioavailability and pharmacokinetics. In addition, the present understanding and management of obesity and diabetes are also focused.

The Potential Protective Effects of Diosmin on Streptozotocin-Induced Diabetic Cardiomyopathy in Rats

BACKGROUND

Diabetic cardiomyopathy (DCM) is a nonischemic myocardial disorder characterized by metabolic disturbances and oxidative stress in diabetic patients. The present paper aims to determine the protective effect of the phlebotrophic drug, diosmin, on DCM in a model of high-fat diet-fed and streptozotocin-induced type 2 diabetes in the rat.

MATERIALS AND METHODS

The animals were divided into 4 groups (8 rats/group) as follows: vehicle-treated nondiabetic control group, vehicle-treated diabetic group, diosmin (50 mg/kg)-treated diabetic group and diosmin (100 mg/kg)-treated diabetic group. Treatment was given once daily orally by gavage for 6 weeks. Oxidant and antioxidant stress markers, inflammatory markers and proapoptotic and antiapoptotic gene expression using quantified real-time polymerase chain reaction were investigated.

RESULTS

Diosmin treatment in diabetic rats lowered elevated blood glucose levels, homeostatic model assessment for insulin resistance, cardiac creatine kinase and lactate dehydrogenase enzymes, cardiac malondialdehyde and nitric oxide. Moreover, diosmin increased plasma insulin and c-peptide levels, cardiac glutathione content, superoxide dismutase, catalase and glutathione S-transferase activities. Also, diosmin treatment significantly (P < 0.05) lowered the levels of interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), down-regulated cardiac Bcl-2-associated X protein and caspase 3 and 9 and up-regulated B-cell lymphoma 2 mRNA expression levels.

CONCLUSIONS

Diosmin may have a sizeable therapeutic potential in the treatment of DCM due to antidiabetic, antioxidative stress, anti-inflammatory and antiapoptotic effects. Detailed studies are needed to disclose the precise mechanisms motivating the protective effect of diosmin‏.

Flavonoids and Their Anti-Diabetic Effects: Cellular Mechanisms and Effects to Improve Blood Sugar Levels

Diabetes mellitus (DM) is a prevailing global health metabolic disorder, with an alarming incidence rate and a huge burden on health care providers. DM is characterized by the elevation of blood glucose due either to a defect in insulin synthesis, secretion, binding to receptor, or an increase of insulin resistance. The internal and external factors such as obesity, urbanizations, and genetic mutations could increase the risk of developing DM. Flavonoids are phenolic compounds existing as secondary metabolites in fruits and vegetables as well as fungi. Their structure consists of 15 carbon skeletons and two aromatic rings (A and B) connected by three carbon chains. Flavonoids are furtherly classified into 6 subclasses: flavonols, flavones, flavanones, isoflavones, flavanols, and anthocyanidins. Naturally occurring flavonoids possess anti-diabetic effects. As in vitro and animal model's studies demonstrate, they have the ability to prevent diabetes and its complications. The aim of this review is to summarize the current knowledge addressing the antidiabetic effects of dietary flavonoids and their underlying molecular mechanisms on selected pathways: Glucose transporter, hepatic enzymes, tyrosine kinase inhibitor, AMPK, PPAR, and NF-κB. Flavonoids improve the pathogenesis of diabetes and its complications through the regulation of glucose metabolism, hepatic enzymes activities, and a lipid profile. Most studies illustrate a positive role of specific dietary flavonoids on diabetes, but the mechanisms of action and the side effects need more clarification. Overall, more research is needed to provide a better understanding of the mechanisms of diabetes treatment using flavonoids.