Antioxidant properties, radical scavenging activity and biomolecule protection capacity of flavonoid naringenin and its glycoside naringin: a comparative study

The Strategy of Boosting the Immune System Under the COVID-19 Pandemic

The novel coronavirus (SARS-CoV-2) infection (COVID-19) has raised considerable concern on the entire planet. On March 11, 2020, COVID-19 was categorized by the World Health Organization (WHO) as a pandemic infection, and by March 18, 2020, it has spread to 146 countries. The first internal defense line against numerous diseases is personalized immunity. Although it cannot be claimed that personalized nutrition will have an immediate impact on a global pandemic, as the nutritional interventions required a long time to induce beneficial outcomes on immunity development, nutritional strategies are still able to clarify and have a beneficial influence on the interplay between physiology and diet, which could make a positive contribution to the condition in the next period. As such, a specific goal for every practitioner is to evaluate different tests to perceive the status of the patient, such as markers of inflammation, insulin regulation, and nutrient status, and to detect possible imbalances or deficiencies. During the process of disease development, the supplementation and addition of different nutrients and nutraceuticals can influence not only the viral replication but also the cellular mechanisms. It is essential to understand that every patient has its individual needs. Even though many nutrients, nutraceuticals, and drugs have beneficial effects on the immune response and can prevent or ameliorate viral infections, it is essential to detect at what stage in COVID-19 progression the patient is at the moment and decide what kind of nutrition intervention is necessary. Furthermore, understanding the pathogenesis of coronavirus infection is critical to make proper recommendations.

Naringenin ameliorates diabetic neuropathic pain by modulation of oxidative-nitrosative stress, cytokines and MMP-9 levels

Diabetes mellitus is a serious debilitating epidemic affecting all social strata, imposing huge health, social and economic burdens.

Molecular Mechanisms That Define Redox Balance Function in Pathogen-Host Interactions-Is There a Role for Dietary Bioactive Polyphenols?

To ensure a functional immune system, the mammalian host must detect and respond to the presence of pathogenic bacteria during infection. This is accomplished in part by generating reactive oxygen species (ROS) that target invading bacteria; a process that is facilitated by NADPH oxidase upregulation. Thus, bacterial pathogens must overcome the oxidative burst produced by the host innate immune cells in order to survive and proliferate. In this way, pathogenic bacteria develop virulence, which is related to the affinity to secrete effector proteins against host ROS in order to facilitate microbial survival in the host cell. These effectors scavenge the host generated ROS directly, or alternatively, manipulate host cell signaling mechanisms designed to benefit pathogen survival. The redox-balance of the host is important for the regulation of cell signaling activities that include mitogen-activated protein kinase (MAPK), p21-activated kinase (PAK), phosphatidylinositol 3-kinase (PI3K)/Akt, and nuclear factor κB (NF-κB) pathways. An understanding of the function of pathogenic effectors to divert host cell signaling is important to ascertain the mechanisms underlying pathogen virulence and the eventual host–pathogen relationship. Herein, we examine the effectors produced by the microbial secretion system, placing emphasis on how they target molecular signaling mechanisms involved in a host immune response. Moreover, we discuss the potential impact of bioactive polyphenols in modulating these molecular interactions that will ultimately influence pathogen virulence.

Sciatic nerve regeneration by using collagen type I hydrogel containing naringin

In the present study, collagen hydrogel containing naringin was fabricated, characterized and used as the scaffold for peripheral nerve damage treatment. The collagen was dissolved in acetic acid, naringin added to the collagen solution, and cross-linked with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide powder (EDC; 0.10 mM) to form the hydrogel. The microstructure, swelling behavior, biodegradation, and cyto/hemocompatibility of the fabricated hydrogels were assessed. Finally, the healing efficacy of the prepared collagen hydrogel loaded with naringin on the sciatic nerve crush injury was assessed in the animal model. The characterization results showed that the fabricated hydrogels have a porous structure containing interconnected pores with the average pore size of 90 µm. The degradation results demonstrated that about 70% of the primary weight of the naringin loaded hydrogel had been lost after 4 weeks of storage in PBS. The in vitro study showed that the proliferation of Schwann cells on the collagen/naringin hydrogel was higher than the control group (tissue culture plate) at both 48 and 72 h after cell seeding and even significantly higher than pure collagen 72 h after cell seeding (*p < 0.005, **p < 0.001). The animal study implied that the sciatic functional index reached to -22.13 ± 3.00 at the end of 60th days post-implantation which was statistically significant (p < 0.05) compared with the negative control (injury without the treatment) (-82.60 ± 1.06), and the pure collagen hydrogel (-59.80 ± 3.20) groups. The hot plate latency test, the compound muscle action potential, and wet weight-loss of the gastrocnemius muscle evaluation confirmed the positive effect of the prepared hydrogels on the healing process of the induced nerve injury. In the final, the histopathologic examinations depicted that the collagen/naringin hydrogel group reduced all the histological changes induced from the nerve injury and showed more resemblance to the normal sciatic nerve, with well-arranged fibers and intact myelin sheath. The overall results implied that the prepared collagen/naringin hydrogel can be utilized as a sophisticated alternative to healing peripheral nerve damages.

Naringenin Suppresses Chemically Induced Skin Cancer in Two-Stage Skin Carcinogenesis Mouse Model

Background: Naringenin, a flavonoid present in citrus fruits has many health promoting activities. It has been reported to protect skin from UV radiation, thermal damage and atopic allergies. Despite many skin protective effects, in vivo effect of naringenin on skin cancer has not been reported so far.Objective: The present work was designed to study the chemo preventive effect of naringenin on chemically induced skin cancer in mice.Methods: Two stage model of skin papillomagenesis, using DMBA plus croton oil, was used to study the effect of naringenin in Swiss albino mice. The chemo preventive effect was evaluated using morphological, histopathological and biochemical features.Results: Oral administration of naringenin reduced the skin papilloma in both pre-treatment as well as post-treatment groups of mice. The number as well as size of papilloma was significantly reduced in the treated groups. Histopathological studies showed that naringenin treatment suppressed papillomagenesis. Biochemical studies further revealed decrease in the activity of glyoxalase-1 enzyme and an increase in carbonyl content. The effect was more pronounced in ant-initiation group.Conclusion: Naringenin exhibited anti-tumor effect in two stage carcinogenesis mouse skin tumor model. This study revealed that consumption of citrus fruits and the naringenin therein may be helpful in suppression of skin cancer.

Yield parameters and antioxidant compounds of tomato fruit: the role of plant defence inducers with or without Cucumber mosaic virus infection

BACKGROUND

The production of fruit and vegetables rich in health-promoting components in an eco-friendly context represents the winning answer to the world population demand for food. In this study, the effects of different treatments on the yield and fruit chemical characteristics of tomato (Solanum lycopersicum L.) are reported. The treatments included three inducers of plant defence responses (chitosan, Trichoderma harzianum T-22 and Bacillus subtilis QST713) applied alone or before Cucumber mosaic virus infection. Fruit production and antioxidant compounds were investigated by ultrahigh-performance liquid chromatography (UHPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

Compared to control fruit harvested from untreated and healthy plants, treatment with QST713 increased the fruit number. Furthermore, plant treatments with T22, QST713 and chitosan alone enhanced fruit carotenoids (lutein and β-carotene), ascorbic acid and phenolic acids (caffeoyl glucoside and p-coumaroyl glucoside). In parallel, compared to fruit harvested from only CMV-infected plants, treatments with T22, QST713 and chitosan before CMV enhanced fruit ascorbic acid and flavonoids (quercetin 3-O-xylosyl-rutinoside and rutin).

CONCLUSION

Antioxidant compounds of tomato fruit can increase with the application of the plant defence inducers, thus protecting both the consumer and plant health. © 2019 Society of Chemical Industry.

Acute Effects of Hesperidin in Oxidant/Antioxidant State Markers and Performance in Amateur Cyclists

Human and animal studies have shown that Hesperidin has the ability to modulate antioxidant and inflammatory state and to improve aerobic performance. The main objective of this study was to assess whether the acute intake of 500 mg of 2S-Hesperidin (Cardiose^®) improves antioxidant status, metabolism, and athletic performance, during and after a rectangular test (aerobic and anaerobic effort). For this, a crossover design was used in 15 cyclists (>1 year of training), with one week of washout between placebo and Cardiose^® supplementation. After the intervention, significant differences in average power (+2.27%, p = 0.023), maximum speed (+3.23%, p = 0.043) and total energy (∑ 4 sprint test) (+2.64%, p = 0.028) between Cardiose^® and placebo were found in the best data of the repeated sprint test. Small changes were also observed in the activity of catalase, superoxide dismutase, reduced glutathione concentration and oxidized/reduced glutathione (GSSG/GSH) ratio, as well as the lipoperoxidation products (thiobarbituric acid reactive substances; TBARS), at different points of the rectangular test, although not significant. Our findings showed improvements in anaerobic performance after Cardiose^® intake, but not in placebo, suggesting the potential benefits of using Cardiose^® in sports with a high anaerobic component.

Bioactive Compounds of Cooked Tomato Sauce Modulate Oxidative Stress and Arachidonic Acid Cascade Induced by Oxidized LDL in Macrophage Cultures

Sofrito is a mix of tomato, onion, garlic, and olive oil, which contains phenolic compounds and carotenoids. Consumption of tomato-based sofrito has been related to a lower risk of cardiovascular events, but the mechanisms behind such beneficial effects remain unclear. This study aimed to analyze the effects of representative sofrito compounds such as naringenin, hydroxytyrosol, lycopene, and β-carotene on mechanisms involved in the pathogenesis of atherosclerosis. We demonstrated that both phenolic compounds and both carotenoids studied were able to inhibit low density lipoproteins (LDL) oxidation, as well as oxidative stress and eicosanoid production induced by oxidized LDL (oxLDL) in macrophage cultures. These effects were not the consequences of disturbing oxLDL uptake by macrophages. Finally, we observed an additive effect of these sofrito compounds, as well as the activity of a main naringenin metabolite, naringenin 7-O-β-d-glucuronide on LDL oxidation and oxidative stress.

Natural combination of phenolic glycosides from fruits resists pro-oxidant insults to colon cells and enhances intrinsic antioxidant status in mice

A combination of fresh fruits adequately supplying required nutrients is likely to have better health benefits by virtue of the synergistic/additive effect of its natural constituents. With this view and aiming to obtain phenolic glycosides in combination, fresh apple, grape, orange, pomegranate, and sapota fruit juices were combined and lyophilized. An aqueous extract of this fruit combination (AEFC) had polyphenols as a major constituent (47.36 μg GAE/mL) and LC–MS analysis documented the presence of cyanidin and pallidol 3-O-glucosides, phloridzin, delphinidin-3-O-rutinoside, kaempferol-3-O-pentoside, quercetin-3-O-rutinoside, trans-caffeic acid. Corroborating this, AEFC exhibited significant DPPH and superoxide radical scavenging activities (IC₅₀values 43.63 and 49.01 μg/mL) and protected colon epithelial cells (HCT-15) against H₂O₂ and AAPH induced cell death by 40 and 72.62% and buthionine sulfoximine (BSO) induced GSH depletion by 52.43%. In normal Swiss albino mice, administration of AEFC for over 30 days improved hepatic and renal GPx, SOD, and catalase activities and GSH levels. The study thus suggests the combinatorial effects of natural phenolic glycosides from fruits in resisting oxidative insults and associated disease pathology.

Nanoformulations of natural products for management of metabolic syndrome

Metabolic syndrome is a common metabolic disorder which has become a public health challenge worldwide. There has been growing interest in medications including natural products as complementary or alternative choices for common chemical therapeutics regarding their limited side effects and ease of access. Nanosizing these compounds may help to increase their solubility, bioavailability, and promisingly enhance their efficacy. This study, for the first time, provides a comprehensive overview of the application of natural-products-based nanoformulations in the management of metabolic syndrome. Different phytochemicals including curcumin, berberine, Capsicum oleoresin, naringenin, emodin, gymnemic acid, resveratrol, quercetin, scutellarin, stevioside, silybin, baicalin, and others have been nanosized hitherto, and their nanosizing method and effect in treatment and alleviating metabolic syndrome have been reviewed and discussed in this study. It has been discovered that there are several pathways or molecular targets relevant to metabolic disorders which are affected by these compounds. Various natural-based nanoformulations have shown promising effect in treatment of metabolic syndrome, and therefore can be considered as future candidates instead of or in conjunction with pharmaceutical drugs if they pass clinical trials successfully.

The effect of naringenin on the role of nuclear factor (erythroid-derived 2)-like2 (Nrf2) and haem oxygenase 1 (HO-1) in reducing the risk of oxidative stress-related radiotoxicity in the spleen of rats

The present study was to evaluate the radiomitigative effect of naringenin (NRG) on the modulation of ionizing radiation (IR)-induced spleen injury. Rats were exposed to 12 Gy (3Gy/two times/week). NRG (50mg/Kg), was orally given one hour after the first radiation dose, and daily continued during the irradiation period. Rats were sacrificed 1 day after the last dose of radiation. NRG showed a significant decrease of malondialdehyde, hydrogen peroxide with a significant elevation of superoxide dismutase, catalase and glutathione peroxidase activities and glutathione content. Moreover, NRG confirmed the intracellular defense mechanisms through activation of nuclear factor (erythroid-derived 2)-like2 (Nrf2) and haem oxygenase-1 (HO-1) levels and their protein expression. In addition, NRG deactivated the nuclear factor-κB (NF-κB) and reduced the pro-inflammatory cytokines. Further, NRG showed positive modulation in the haematological values (WBCs, RBCs, Hb, Hct% and PLt). In conclusion, these results suggested that NRG reversed the IR-induced redox-imbalance in the rat spleen.

In ovo injection of flavanone on bone quality characteristics, biochemical parameters and antioxidant enzyme status of blood in daily chicks

In ovo injection (IOI) of Naringin (N), flavanone was examined on post-hatch blood biochemical parameters, antioxidant status and bone characteristics. Fertile eggs (n = 700) were distributed in seven groups with 100 eggs. On 14th and 17.5th days of incubation, four groups were injected using 15 or 30 mg active ingredient levels of naringin/0.5 ml saline/egg, low and high level, into amnion sac. Controls include sham (injected normal saline, 0.5 ml/egg on day 14 and 17.5th) and un-injected group. IOI of high naringin and saline on 14th day of incubation resulted in lower hatchability and then higher mortality in last week of embryonic life. On day hatch, high levels of injected groups more body weight compared to the control. Chick length was increased at high levels of naringin on day 17.5th compared to control and saline injected. Quality traits of bones were improved in naringin-injected groups compared to control. IOI of naringin influenced thyroid hormones on 14th day of incubation. Naringin groups influenced the Alkaline phosphatase (ALP), Calcium (Ca), superoxide dismutase (SOD), blood biochemical and lipids. Totally, amniotic IOI of naringin in last days of developing embryo may be useful for hatched chick, development of leg long bone or effect on biochemical metabolites by levels of flavanone that it needs more research.

Beneficial Effects of Citrus Flavonoids on Cardiovascular and Metabolic Health

The prevalence of cardiovascular disease (CVD) is increasing over time. CVD is a comorbidity in diabetes and contributes to premature death. Citrus flavonoids possess several biological activities and have emerged as efficient therapeutics for the treatment of CVD. Citrus flavonoids scavenge free radicals, improve glucose tolerance and insulin sensitivity, modulate lipid metabolism and adipocyte differentiation, suppress inflammation and apoptosis, and improve endothelial dysfunction. The intake of citrus flavonoids has been associated with improved cardiovascular outcomes. Although citrus flavonoids exerted multiple beneficial effects, their mechanisms of action are not completely established. In this review, we summarized recent findings and advances in understanding the mechanisms underlying the protective effects of citrus flavonoids against oxidative stress, inflammation, diabetes, dyslipidemia, endothelial dysfunction, and atherosclerosis. Further studies and clinical trials to assess the efficacy and to explore the underlying mechanism(s) of action of citrus flavonoids are recommended.

Naringin prevents ultraviolet-B radiation-induced oxidative damage and inflammation through activation of peroxisome proliferator-activated receptor γ in mouse embryonic fibroblast (NIH-3T3) cells

The present study, we investigate the preventive role of naringin, a dietary flavonoid, against ultraviolet-B (UVB) radiation (280-320 nm) induced oxidative damage and inflammatory responses in mouse embryonic fibroblast cell lines (NIH-3T3). In this study, 20 mJ/cm 2 of UVB radiation induces cell cytotoxicity, reactive oxygen species (ROS) generation, DNA damage, and antioxidants depletion in NIH-3T3 cells. Treatment with naringin (60 µM) prior UVB exposure prevented the cell cytotoxicity, ROS generation, DNA damage, and antioxidants depletion in NIH-3T3 cells. Furthermore, naringin prevents UVB-induced mitogen-activated protein kinase families and nuclear factor-κB (NF-κB)-mediated activation of inflammatory factors, that is TNF-α, IL-6, IL-10, and COX-2 in NIH-3T3 cells. Peroxisome proliferator-activated receptor γ (PPARγ) is an anti-inflammatory agent and it suppressed the UVB-mediated oxidative and inflammatory responses. In this study, naringin activates PPARγ and prevents inflammatory biomarkers in NIH-3T3 cells. Thus, naringin prevents UVB-mediated inflammation and oxidative damage in NIH-3T3 cells probably over controlling NF-κB expression and activation of PPARγ.

Halophytic Grasses, a New Source of Nutraceuticals? A Review on Their Secondary Metabolites and Biological Activities

The Poaceae family, known as grasses, is distributed worldwide and is considered the most important group of monocotyledonous crops. Salt stress is multifactorial, therefore to survive, halophytes evolved a variety of adaptations, which include the biosynthesis of different primary and secondary metabolites. This trait enhances the accumulation of important families of compounds crucial to the prevention of a variety of chronic diseases. Besides, if proven edible, these species could cope with the increased soil salinity responsible for the decline of arable land due to their high nutritional/nutraceutical value. Herein, the phytochemical investigations performed in halophytes from the Poaceae family as well as their biological properties were explored. Among the 65 genera and 148 species of known halophytic grasses, only 14% of the taxa were studied phytochemically and 10% were subjected to biological evaluation. Notably, in the studied species, a variety of compound families, as well as bioactivities, were demonstrated, highlighting the potential of halophytic grasses.

The Protective Effect of Naringenin on Oxaliplatin-Induced Genotoxicity in Mice

Oxaliplatin is a third generation platinum based anti-cancer drug used against various human malignancies but displays genotoxic properties against normal cells. Naringenin is a naturally occurring bioflavonoid that possesses anti-oxidant properties and has protective effects against DNA damage. The aim of this study is to examine the protective effects of naringenin on oxaliplatin-induced DNA damage in mice. A total of 50, male BALB/c mice were randomly divided equally into five groups. Oxaliplatin toxicity was induced by a single dose (7 mg/kg body weight (b.w.)) injection (intraperitoneally (i.p.)) of oxaliplatin. Naringenin was given orally for ten consecutive days at two doses, 20 mg/kg b.w. (dose I) and 40 mg/kg b.w. (dose II), to group I and group II, respectively. On the tenth day of the experiment, animals in groups III, IV, and V were given a single i.p. injection of oxaliplatin (7 mg/kg b.w.). All the animals were sacrificed 24 h after oxaliplatin treatment. The extent of genotoxicity was assessed by multiple genotoxicity assays (8-hydroxydeoxy-guanosine marker, comet, micronucleus and chromosomal aberration assays, oxidative stress-marker Glutathione evaluation) in order to determine diverse kinds of DNA damage. The results indicated that naringenin administration significantly reduced the DNA damage induced by oxaliplatin possibly due to its strong anti-oxidant properties. The results suggest that naringenin is a potential candidate for future development as a chemoprotective agent against chemotherapy associated complications.

Naringenin Cocrystals Prepared by Solution Crystallization Method for Improving Bioavailability and Anti-hyperlipidemia Effects

Naringenin exerts anti-inflammatory, hypolipidemic, and hepatoprotective effects; however, it shows low oral bioavailability because of poor water solubility. In this work, cocrystals of naringenin were formed to address these issues. Using the solution crystallization method, various naringenin cocrystals were prepared with different cocrystal coformers, including naringenin-nicotinamide, naringenin-isonicotinamide, naringenin-caffeine, naringenin-betaine, and naringenin-L-proline. The formation of these cocrystals was assayed by using DSC, XRD, and FT-IR spectroscopy. The stoichiometric ratio of naringenin and the CCFs in the corresponding cocrystals was investigated by NMR. The solubility of naringenin, as well as its dissolution rate, was markedly improved by forming cocrystals. The oral bioavailability of naringenin administered as naringenin-L-proline and naringenin-betaine cocrystals was achieved significantly greater than that of pure naringenin (p < 0.05). In particular, the C_max of naringenin-L-proline and naringenin-betaine cocrystals were 2.00-fold and 3.35-fold higher, and the AUC of naringenin-L-proline and naringenin-betaine cocrystals were 2.39-fold and 4.91-fold, respectively, higher than pure naringenin in rats. With the naringenin-betaine cocrystals for oral delivery, the drug distribution in the liver was significantly increased compared to pure naringenin. Accordingly, the naringenin-betaine cocrystals showed improved anti-hyperlipidemia effects on the C57 BL/6J PNPLA3 I148M transgenic mouse hyperlipidemia model. Collectively, cocrystal formation is a promising way to increase the bioavailability of naringenin for treating hyperlipidemia.

Identification and Extraction Optimization of Active Constituents in Citrus junos Seib ex TANAKA Peel and Its Biological Evaluation

Citrus junos Seib ex TANAKA possesses various biological effects. It has been used in oriental remedies for blood circulation and the common cold. Recently, biological effects of C. junos peel have been reported. However, optimization of the biological properties of C. junos peel preparations has yet to be reported on. We developed a high-performance liquid chromatography (HPLC) method for quantification of the active constituents in C. junos peel. Hot water and ethanolic extracts of C. junos peel were prepared and their chemical profiles and biological activities were evaluated. The 80% ethanolic extract demonstrated the greatest antioxidant activity and phenolic content, while the 100% ethanolic extract had the greatest xanthine oxidase inhibitory activity. Elastase inhibition activity was superior in aqueous and 20% ethanolic extracts. The contents of two flavonoids were highest in the 100% ethanolic extract. We postulated that the antioxidant and anti-aging effects of C. junos peel extract could be attributed to phenolics such as flavonoids. Our results suggest that the flavonoid-rich extract of C. junos may be utilized for the treatment and prevention of metabolic disease and hyperuricemia while the water-soluble extract of C. junos could be used as a source for its anti-aging properties.

Preventive Effect of Naringin on Metabolic Syndrome and Its Mechanism of Action: A Systematic Review

BACKGROUND

Metabolic syndrome (MetS), which consists of cluster of conditions, hypertension, hyperlipidemia, hyperglycemia, and visceral obesity, is affecting population worldwide. Studies have shown that plant derived flavonoids have the ability to alleviate MetS. Naringin is a type of glycoside flavonoid found in most plant and it plays a critical role in the treatment of MetS due to its antioxidant activity and ability to regulate cytokines.

METHODS

A systematic review was done to study the effects of naringin on the metabolic diseases using electronic databases which include Ovid and Scopus using specific descriptors published from the year 2010 till present to provide updated literature on this field. The articles were assessed and chosen based on the criteria in which the mechanisms and effects of naringin on different metabolic diseases were reported.

RESULTS

Thirty-four articles were identified which referred to the studies that correspond to the previously stated criteria. Subsequently after screening for the articles that were published after the year 2010, finally, 19 articles were selected and assessed accordingly. Based on the assessment, naringin could alleviate MetS by reducing visceral obesity, blood glucose, blood pressure, and lipid profile and regulating cytokines.

CONCLUSIONS

Naringin is an antioxidant that appears to be efficacious in alleviating MetS by preventing oxidative damage and proinflammatory cytokine release. However, the dosage used in animal studies might not be achieved in human trials. Thus, adequate investigation needs to be conducted to confirm naringin's effects on humans.

Synthesis and encapsulation of V(IV,V) compounds in silica nanoparticles targeting development of antioxidant and antiradical nanomaterials

The quest for effective treatments of oxidative stress has concentrated over the years on new nanomaterials with improved antioxidant and antiradical activity, thereby attracting broad research interest. In that regard, research efforts in our lab were launched to pursue such hybrid materials involving a) synthesis of silica gel matrices, b) evaluation of the suitability of atoxic matrices as potential carriers for the controlled release of V(IV)(VOSO₄), V(V)(NaVO₃) compounds and a newly synthesized heterometallic lithium-vanadium(IV,V) tetranuclear compound containing vanadium-bound hydroxycarboxylic 1,3-diamine-2-propanol-N,N,N',N'-tetraacetic acid (DPOT), and c) investigation of structural and textural properties of silica nanoparticles (NPs) by different and complementary characterization techniques, inquiring into the nature of the encapsulated vanadium species and their interaction with the siloxane matrix, collectively targeting novel antioxidant and antiradical nanomaterials biotechnology. The physicochemical characterization of the vanadium-loaded SiO₂ NPs led to the formulation of optimized material configuration linked to the delivery of the encapsulated antioxidant-antiradical load. Entrapment and drug release studies showed a) the competence of hybrid nanoparticles with respect to encapsulation efficiency of the vanadium compound (concentration dependence), b) congruence with the physicochemical features determined, and c) a well-defined release profile of NP load. Antioxidant properties and the free radical scavenging capacity of the new hybrid materials (containing VOSO₄, NaVO₃, and V-DPOT) were demonstrated through a) 2-diphenyl-1-picrylhydrazyl (DPPH) free radical, and b) intracellular-extracellular reactive oxygen species (ROS) assays, through UV-Visible spectroscopy techniques, collectively showing that the hybrid silica NPs (empty-loaded) could serve as an efficient platform for nanodrug formulations counteracting oxidative stress.

Naringin in a combined therapy with phenytoin on pentylenetetrazole-induced kindling in rats

Phenytoin (Dilantin) is an orally active, use-dependent voltage-gated sodium channel inhibitor and is a potent, economical, and widely used anticonvulsant agent. The objective of the present study was to investigate the effect of the combined treatment of naringin (40 mg/kg and 80 mg/kg) and phenytoin on prevention of seizure attacks, development of kindling, oxidative stress, cognitive impairment, and neurochemicals in the frontal cortex, temporal cortex, and hippocampus, and morphological changes in the hippocampus. Treatment with the high dose of naringin (80 mg/kg) along with phenytoin has shown to offer protection against seizures, development of kindling, and cognition enhancement through Y-maze test and improved % conditioned avoidance response (% CAR) through pole climbing test in pentylenetetrazole (PTZ)-induced kindling model. It has also been shown to improve neurochemical balance by elevating levels of Gamma amino butyric acid (GABA) and dopamine, decreasing levels of glutamate, oxidative biomarker (malondialdehyde (MDA)), and increasing levels of antioxidants (glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and total thiol and offered neuroprotection in the hippocampus. So, coadministration of naringin with phenytoin offers a potential treatment option for drug-resistant epilepsy and associated comorbidities. Interpretable research on flavonoids will support the clinical evidence for the recommendation of flavonoids as supplements with antiepileptic drugs (AEDs) for curtailing pharmacoresistant epilepsy and AED-associated comorbidities.

Glutathione depleting drugs, antioxidants and intestinal calcium absorption

Glutathione (GSH) is a tripeptide that constitutes one of the main intracellular reducing compounds. The normal content of GSH in the intestine is essential to optimize the intestinal Ca²⁺ absorption. The use of GSH depleting drugs such as DL-buthionine-S,R-sulfoximine, menadione or vitamin K₃, sodium deoxycholate or diets enriched in fructose, which induce several features of the metabolic syndrome, produce inhibition of the intestinal Ca²⁺ absorption. The GSH depleting drugs switch the redox state towards an oxidant condition provoking oxidative/nitrosative stress and inflammation, which lead to apoptosis and/or autophagy of the enterocytes. Either the transcellular Ca²⁺ transport or the paracellular Ca²⁺ route are altered by GSH depleting drugs. The gene and/or protein expression of transporters involved in the transcellular Ca²⁺ pathway are decreased. The flavonoids quercetin and naringin highly abrogate the inhibition of intestinal Ca²⁺ absorption, not only by restoration of the GSH levels in the intestine but also by their anti-apoptotic properties. Ursodeoxycholic acid, melatonin and glutamine also block the inhibition of Ca²⁺ transport caused by GSH depleting drugs. The use of any of these antioxidants to ameliorate the intestinal Ca²⁺ absorption under oxidant conditions associated with different pathologies in humans requires more investigation with regards to the safety, pharmacokinetics and pharmacodynamics of them.

Pharmacokinetic, pharmacodynamic and formulations aspects of Naringenin: An update

Phenolic compounds constitute one of the important classes of secondary metabolites in the plants. Flavonoids are primary phenolic compounds found in natural drugs. Naringenin is a flavanone, aglycone of Naringin, predominantly found in citrus fruits with various pharmacological activities. Large number of scientific papers has been published on Naringenin describing its structure, physicochemical properties and its therapeutic use in different diseases. This review provides highlights of Naringenin with respect to its distribution, pharmacokinetic and its use in conditions like oxidative stress, inflammation, cancer, diabetes, cardiovascular diseases and neurological disorders. Furthermore, the review also focuses on molecular level mechanisms of Naringenin for its therapeutic effect. Various attempts have been made to formulate advanced dosage forms to address issue of solubility of Naringenin. Systematic review of data published on formulation aspects of Naringenin has also been presented in the article.

Antioxidative effect of flavonoid naringenin in the lenses of type 1 diabetic rats

Oxidative stress arising during diabetes may lead to cataract formation. Thus, in order to prevent oxidative stress development, antioxidants could be considered helpful agents. Naringenin, a flavonoid with a well-documented antioxidative activity, can be found in many plant-derived products, especially citrus fruits. The aim of the study was to examine the effect of naringenin on oxidative stress markers in the lenses of type 1 diabetic rats. The study was conducted on 3-month-old male Wistar rats with streptozotocin-induced type 1 diabetes. The rats were treated orally with naringenin at the doses of 50 and 100 mg/kg for 4 weeks. In the lenses obtained from the animals, enzymatic and non-enzymatic parameters connected with oxidative stress were measured. The enzymatic parameters included superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase activity. For non-enzymatic parameters, the total thiol groups, reduced and oxidized glutathione, protein carbonyl groups, advanced oxidation protein products, malondialdehyde and vitamin C level were assayed. Oral administration of naringenin counteracted most of the unfavorable changes induced by diabetes, including reduction of elevated antioxidative enzymes activity and amelioration of oxidative damage in proteins and lipids. Naringenin administered orally reduces oxidative stress markers in the lenses of type 1 diabetic rats.

Chemiluminescence quenching microarrays for high throughput screening of antioxidants and its application in evaluating herbal extracts and pure compounds

In this paper, a novel high throughput screening method for antioxidants was described. The screening process was completed on a 5 cm × 5 cm silica gel 60 plate. Luminol was used as the fluorogenic substrate while hydrogen peroxide employed to excite the chemiluminescence. A dark spot was observed due to quenching effect of antioxidant. A linear model of the integral area of the spot as a function of analyte amount was fit by using vitamin C as positive control. Excellent linearity (R² = 0.9978) was obtained in the range of 2.31-23.1 μg. The variation coefficients of intra- and inter-chip precisions were below 5% (n = 10) and 10% (n = 6) respectively. The new method was validated by comparing the analysis result of six flavonoids with that from a sequential injection method. The Pearson correlation coefficient was up to 0.98. A set of traditionally used herbal medicines was screened, and Rhei Radix et Rhizoma showed the strongest signal. The major bioactive ingredients were further assigned by flow injection and MS analyses. These results reveal the prospects of the proposed method to supply a promising tool in vitro for high throughput screening and activity evaluation of antioxidants in a fast, low-cost and reliable manner.

A pathway for every product? Tools to discover and design plant metabolism

The vast diversity of plant natural products is a powerful indication of the biosynthetic capacity of plant metabolism. Synthetic biology seeks to capitalize on this ability by understanding and reconfiguring the biosynthetic pathways that generate this diversity to produce novel products with improved efficiency. Here we review the algorithms and databases that presently support the design and manipulation of metabolic pathways in plants, starting from metabolic models of native biosynthetic pathways, progressing to novel combinations of known reactions, and finally proposing new reactions that may be carried out by existing enzymes. We show how these tools are useful for proposing new pathways as well as identifying side reactions that may affect engineering goals.

The Modulatory Properties of Li-Ru-Kang Treatment on Hyperplasia of Mammary Glands Using an Integrated Approach

Background: Li-Ru-Kang (LRK) has been used in the treatment of hyperplasia of mammary glands (HMG) for several decades and can effectively improve clinical symptoms. This study aims to investigate the mechanism by which LRK intervenes in HMG based on an integrated approach that combines metabolomics and network pharmacology analyses. Methods: The effects of LRK on HMG induced by estrogen-progesterone in rats were evaluated by analyzing the morphological and pathological characteristics of breast tissues. Moreover, UPLC-QTOF/MS was performed to explore specific metabolites potentially affecting the pathological process of HMG and the effects of LRK. Pathway analysis was conducted with a combination of metabolomics and network pharmacology analyses to illustrate the pathways and network of LRK-treated HMG. Results: Li-Ru-Kang significantly improved the morphological and pathological characteristics of breast tissues. Metabolomics analyses showed that the therapeutic effect of LRK was mainly associated with the regulation of 10 metabolites, including prostaglandin E2, phosphatidylcholine, leukotriene B4, and phosphatidylserine. Pathway analysis indicated that the metabolites were related to arachidonic acid metabolism, glycerophospholipid metabolism and linoleic acid metabolism. Moreover, principal component analysis showed that the metabolites in the model group were clearly classified, whereas the metabolites in the LRK group were between those in the normal and model groups but closer to those in the normal group. This finding indicated that these metabolites may be responsible for the effects of LRK. The therapeutic effect of LRK on HMG was possibly related to the regulation of 10 specific metabolites. In addition, we further verified the expression of protein kinase C alpha (PKCα), a key target predicted by network pharmacology analysis, and showed that LRK could significantly improve the expression of PKCα. Conclusion: Our study successfully explained the modulatory properties of LRK treatment on HMG using metabolomics and network pharmacology analyses. This systematic method can provide methodological support for further understanding the complex mechanism underlying HMG and possible traditional Chinese medicine (TCM) active ingredients for the treatment of HMG.

Summer savory (Satureja hortensis L.) extract: Phytochemical profile and modulation of cisplatin-induced liver, renal and testicular toxicity

The aim of our study was to examine the potential ameliorating effect of the methanolic extract of Satureja hortensis L. (summer savory) aerial parts against cisplatin-induced oxidative damage in renal, hepatic, and testicular tissues. S. hortensis methanol extract at the doses of 50, 100 and 200 mg/kg of body weight were orally administered to Wistar rats once daily for 10 days. Toxicity was induced by intraperitoneal injection of a single dose of cisplatin (7.5 mg/kg of body weight) on the 5th day of the experiment. Applied treatment with S. hortensis extract restored tissue morphology, ameliorated levels of serum parameters for liver, renal and testes function, tissue oxidative stress parameters, and increased Bcl-2/Bax ratio as an indicator of apoptosis in experimental animals caused by application of cisplatin. UHPLC/DAD/HESI-MS/MS analysis revealed that S. hortensis extract was rich in phenolic compounds with rosmarinic acid (24.9 mg/g) as the main compound, followed by caffeic acid (1.28 mg/g) and naringenin (1.06 mg/g). Our findings suggest that S. hortensis may be a valuable source of dietary and pharmacologically important phenolic compounds, especially rosmarinic acid, in pharmaceutical and functional food formulations in order to maintain normal health conditions or as a remedy in various diseases caused by oxidative damage.

Beneficial effects of naringenin in liver diseases: Molecular mechanisms

Liver diseases are caused by different etiological agents, mainly alcohol consumption, viruses, drug intoxication or malnutrition. Frequently, liver diseases are initiated by oxidative stress and inflammation that lead to the excessive production of extracellular matrix (ECM), followed by a progression to fibrosis, cirrhosis and hepatocellular carcinoma (HCC). It has been reported that some natural products display hepatoprotective properties. Naringenin is a flavonoid with antioxidant, antifibrogenic, anti-inflammatory and anticancer properties that is capable of preventing liver damage caused by different agents. The main protective effects of naringenin in liver diseases are the inhibition of oxidative stress, transforming growth factor (TGF-β) pathway and the prevention of the transdifferentiation of hepatic stellate cells (HSC), leading to decreased collagen synthesis. Other effects include the inhibition of the mitogen activated protein kinase (MAPK), toll-like receptor (TLR) and TGF-β non-canonical pathways, the inhibition of which further results in a strong reduction in ECM synthesis and deposition. In addition, naringenin has shown beneficial effects on nonalcoholic fatty liver disease (NAFLD) through the regulation of lipid metabolism, modulating the synthesis and oxidation of lipids and cholesterol. Moreover, naringenin protects from HCC, since it inhibits growth factors such as TGF-β and vascular endothelial growth factor (VEGF), inducing apoptosis and regulating MAPK pathways. Naringenin is safe and acts by targeting multiple proteins. However, it possesses low bioavailability and high intestinal metabolism. In this regard, formulations, such as nanoparticles or liposomes, have been developed to improve naringenin bioavailability. We conclude that naringenin should be considered in the future as an important candidate in the treatment of different liver diseases.

Naringin Protects Pancreatic β-Cells Against Oxidative Stress-Induced Apoptosis by Inhibiting Both Intrinsic and Extrinsic Pathways in Insulin-Deficient Diabetic Mice

SCOPE

Oxidative stress has been suggested to play a central role in the pathogenesis of diabetes, as well as other metabolic disorders. Naringin, a major flavanone glycoside in citrus species, has been shown to display strong antioxidant potential in in vitro and in vivo models of oxidative stress; however, the underlying protective mechanisms in diabetes are unclear.

METHODS AND RESULTS

To study the protective effects and molecular mechanisms of naringin in preventing islet dysfunction and diabetes, we examined glucose homeostasis, β-cell apoptosis, and inflammatory response in insulin-deficient diabetic mice exposed to acute oxidative stress with streptozotocin (STZ). Naringin dose-dependently ameliorated hyperglycemia and islet dysfunction in insulin-deficient diabetic mice. Naringin counteracted STZ-induced β-cell apoptosis by inhibiting both the intrinsic (mitochondria-mediated) and extrinsic (death receptor-mediated) pathways. Furthermore, these protective effects were associated with suppression of DNA damage response and nuclear factor-kappa B- and mitogen-activated protein kinase-mediated signaling pathways, as well as reduction of reactive oxygen species accumulation and pro-inflammatory cytokine production in the pancreas.

CONCLUSION

Taken together, our study provides insights into the underlying mechanisms through which naringin protects the pancreatic β-cells against oxidative stress-induced apoptosis.

Do flavanols-rich natural products relieve obesity-related insulin resistance?

Growing evidence support that insulin resistance may occur as a severe problem due to chronic energetic overfeeding and subsequent obesity. When an abundance of glucose and saturated fat enter the cell, impaired blood flow, hypoxia, inflammation and macrophage infiltration in obese adipose tissue may induce oxidative stress and insulin resistance. Excessive circulating saturated fatty acids ectopically accumulate in insulin-sensitive tissues and impair insulin action. In this context, excessive hepatic lipid accumulation may play a central, pathogenic role in insulin resistance. It is thought that dietary polyphenols may ameliorate obesity-related insulin resistance by attenuating inflammatory responses and oxidative stress. The most often occurring natural polyphenolic compounds are flavonoids. In this review, the possible mechanistic effect of flavonoid-rich natural products on insulin resistance-related metabolic pathways is discussed. Polyphenol intake can prevent high-fat-diet-induced insulin resistance via cell surface G protein-coupled estrogen receptors by upregulating the expression of related genes, and their pathways, which are responsible for the insulin sensitivity.

OptPipe - a pipeline for optimizing metabolic engineering targets

BACKGROUND

We propose OptPipe - a Pipeline for Optimizing Metabolic Engineering Targets, based on a consensus approach. The method generates consensus hypotheses for metabolic engineering applications by combining several optimization solutions obtained from distinct algorithms. The solutions are ranked according to several objectives, such as biomass and target production, by using the rank product tests corrected for multiple comparisons.

RESULTS

OptPipe was applied in a genome-scale model of Corynebacterium glutamicum for maximizing malonyl-CoA, which is a valuable precursor for many phenolic compounds. In vivo experimental validation confirmed increased malonyl-CoA level in case of ΔsdhCAB deletion, as predicted in silico.

CONCLUSIONS

A method was developed to combine the optimization solutions provided by common knockout prediction procedures and rank the suggested mutants according to the expected growth rate, production and a new adaptability measure. The implementation of the pipeline along with the complete documentation is freely available at https://github.com/AndrasHartmann/OptPipe .

Naringin improves random skin flap survival in rats

Background

Random-pattern flap transfer is commonly used to treat soft-tissue defects. However, flap necrosis remains a serious problem. Naringin accelerates angiogenesis by activating the expression of vascular endothelial growth factor (VEGF). In the present study, we investigated whether naringin improves the survival of random skin flaps.

Results

Compared with controls, the naringin-treated groups exhibited significantly larger mean areas of flap survival, significantly increased SOD activity and VEGF expression, and significantly reduced MDA level. Hematoxylin and eosin (HE) staining revealed that naringin promoted angiogenesis and inhibited inflammation.

Materials and Methods

“McFarlane flap” models were established in 90 male Sprague-Dawley (SD) rats divided into three groups: a 40 mg/kg control group (0.5 % sodium carboxymethylcellulose), a 40 mg/kg naringin-treated group, and an 80 mg/kg naringin-treated group. The extent of necrosis was measured 7 days later, and tissue samples were subjected to histological analysis. Angiogenesis was evaluated via lead oxide–gelatin angiography, immunohistochemistry, and laser Doppler imaging. Inflammation was evaluated by measurement of serum TNF-α (tumor necrosis factor-α) and IL-6 (interleukin-6) levels. Oxidative stress was assessed by measuring superoxide dismutase (SOD) activity and the malondialdehyde (MDA) level.

Conclusion

Naringin improved random skin flap survival.

Neutrophil extracellular traps in acrolein promoted hepatic ischemia reperfusion injury: Therapeutic potential of NOX2 and p38MAPK inhibitors

Neutrophil is a significant contributor to ischemia reperfusion (IR) induced liver tissue damage. However, the exact role of neutrophils in IR induced innate immune activation and liver damage is not quite clear. Our study sheds light on the role of chronic oxidative stress end products in worsening the IR inflammatory process by neutrophil recruitment and activation following liver surgery. We employed specific inhibitors for molecular targets-NOX2 (NADPH oxidase 2) and P38 MAPK (Mitogen activated protein kinase) signal to counteract neutrophil activation and neutrophil extracellular trap (NET) release induced liver damage in IR injury. We found that acrolein initiated neutrophil chemotaxis and induced NET release both in vitro and in vivo. Acrolein exposure caused NET induced nuclear and mitochondrial damage in HepG2 cells as well as aggravated the IR injury in rat liver. Pretreatment with F-apocynin and naringin, efficiently suppressed acrolein induced NET release in vitro. Notably, it suppressed the expression of inflammatory cytokines, P38MAPK-ERK activation, and apoptotic signals in rat liver exposed to acrolein and subjected to IR. Moreover, this combination effectively attenuated acrolein induced NET release and hepatic IR injury. In the current study we have shown that the acrolein accumulation in liver due to chronic stress, is responsible for neutrophil recruitment and its activation leading to NET induced liver damage during surgery. Our study shows that therapeutic targeting of NOX2 and P38MAPK signaling in patients with chronic hepatic disorders would improve post operative hepatic function and survival.

Further Antinociceptive Properties of Naringenin on Acute and Chronic Pain in Mice

Naringenin (NG) is a flavanone abundant in grapefruit and other citrus fruits that presents several pharmacological effects, such as antioxidant, anti-inflammatory, analgesic, among others. We investigated the antinociception of systemic administration of naringenin (NG) and some of the mechanisms of action underlying its effect. Intraperitoneal administration of NG (10 mg/kg) inhibited the mechanical allodynia induced by partial sciatic nerve ligation (PSNL) and carrageenan in 65 ± 4 and 43 ± 9% (2 h), respectively. NG also reduced the writhes number (30 mg/kg: 90 ± 9%) and the nociceptive response of formalin (100 mg/kg: 75 ± 12%, inflammatory phase), bradykinin (30 mg/kg: 79 ± 6%) and prostaglandin E2 (100 mg/kg: 98 ± 1%). Besides, NG reduced the glutamate-induced nociception with ID50 value of 66 mg/kg, effect that was reversed by naloxone. NG, at antinociceptive doses, did not affect the locomotor activity. Our findings demonstrated that systemic NG exerts anti-allodynic activity in neuropathic pain model and antinociceptive effect in several chemical and inflammatory models of nociception, with participation of glutamatergic and opioid system.

Chemical Composition and Antioxidant, Antinociceptive, and Anti-inflammatory Activities of Four Amazonian Byrsonima Species

Species of the Byrsonima genus are widely used in Brazil, especially for the treatment of gastrointestinal disorders. However, species from the Amazonian region are still poorly studied. Thus, we studied the antioxidant, antinociceptive, and anti-inflammatory activities of for Amazonian species, Byrsonima crispa, Byrsonima duckeana, Byrsonima garcibarrigae, and Byrsonima incarnata. Phenolic composition was determined by chemical and chromatographic methods. The aqueous extracts were evaluated in DPPH^• , ABTS^+• , and superoxide (O₂^•- ) tests, LPS-activated macrophage assay, and formalin test. All species contained a high phenolic and flavonoid content. We identified 15 phenolic compounds, including phenolic acids, hydroxycinnamic acids, flavonoids, and catechins. The extracts showed high antioxidant activity and were more active than quercetin at inhibiting nitric oxide release in the LPS-activated macrophage assay. B. duckeana and B. garcibarrigae showed higher in vivo antinociceptive and anti-inflammatory activities. B. garcibarrigae presented significant effect on the early phase of the formalin test, pointing to an antinociceptive mechanism distinct from traditional anti-inflammatory medicines. In conclusion, the pharmacological potential of these species is closely related to their flavonoid-rich chemical composition, which seems to act through antioxidant mechanisms. Copyright © 2017 John Wiley & Sons, Ltd.