Naringenin accords hepatoprotection from streptozotocin induced diabetes in vivo by modulating mitochondrial dysfunction and apoptotic signaling cascade

Naringin Prevents Diabetic-Induced Dysmetabolism in Male Wistar Rats by Modulating GSK-3 Activities and Oxidative Stress-Dependent Pathways

Type 2 diabetes mellitus (T2DM), characterized by insulin resistance and glucose dysmetabolism, is a major metabolic disorder accompanied with health and financial burden. Recently, research findings showed that orange peel extract (OPE) has health benefits such as improved insulin sensitivity and glucose metabolism. The present study aimed at establishing the role of naringin from OPE on T2DM-induced glucose and lipid dysmetabolism. Thirty male (30) Wistar rats were randomized into five groups: control, diabetes, diabetes + naringin, diabetes + orange peel, and diabetes + metformin. Oral administration was once per day for 28 days. After 28 days of treatment, naringin ameliorated the diabetes-induced increase in blood sugar, homeostatic model assessment (HOMA) IR, triglyceride, total cholesterol, triglyceride/high density lipoprotein, total cholesterol/high density lipoprotein, triglyceride glucose index, glucose synthase kinase-3, lactate, lactate dehydrogenase, malondialdehyde, c-reactive protein, and tumor necrosis factor α compared with the diabetic untreated animals. Furthermore, naringin reversed diabetes-induced decrease in serum insulin, HOMA B, HOMA S, quantitative insulin-sensitivity check index, high-density lipoprotein, total antioxidant capacity, superoxide dismutase, catalase, glucose transporter-4, and hepatic glycogen. This study showed that naringin prevented diabetes-induced dysglycemia and dyslipidemia via glucose synthase kinase-3 and oxidative stress-dependent pathways.

Superoxide dismutase ameliorates oxidative stress and regulates liver transcriptomics to provide therapeutic benefits in hepatic inflammation

Background

Oxidative stress refers to the imbalance between oxidants and antioxidants in organisms and often induces hepatic inflammation. Supplementing exogenous superoxide dismutase is an effective way to alleviate oxidative stress; however, the effects and mechanisms by which superoxide dismutase alleviates hepatic inflammation remain unclear.

Methods

This study established a Kunming mouse model to verify and investigate the oxidative stress and hepatic inflammation-alleviating effects of the superoxide dismutase oral supplement that was prepared by our research group in a previous study.

Results

The superoxide dismutase product significantly restored the body weight and liver alanine transaminase, aspartate aminotransferase, superoxide dismutase, catalase, glutathione, and glutathione peroxidase levels of oxidative stress induced mice. Moreover, exogenous superoxide dismutase significantly inhibited interleukin 1β and interleukin 6 mRNA expression in the livers of mice with hepatic inflammation. Transcriptomic analysis indicated that superoxide dismutase had a significant inhibitory effect on Endog expression, alleviating oxidative stress damage, and mediating liver cell apoptosis by regulating the expression of Rab5if, Hnrnpab, and Ifit1.

Conclusion

Our research verified the oxidative stress remediation effects of superoxide dismutase and its therapeutic role against hepatic inflammation. This study can lay a foundation for investigating the mechanism by which superoxide dismutase alleviates hepatic disease.

Orange Peel Extract and Physical Exercise Synergistically Ameliorate Type 2 Diabetes Mellitus-Induced Dysmetabolism by Upregulating GLUT4 Concentration in Male Wistar Rats

Diabetes mellitus (DM) is a chronic disease and one of the oldest known disorders. It is characterized by dysglycemia, dyslipidemia, insulin resistance (IR), and pancreatic cell dysfunction. Although different drugs, metformin (MET), glipizide, glimepiride, etc., have been introduced to treat type 2 DM (T2DM), these drugs are not without side effects. Scientists are now seeking natural treatments such as lifestyle modification and organic products known with limited side effects. Thirty-six male Wistar rats were randomized into six groups (n = 6 per group): control, DM untreated rats, DM+orange peel extract (OPE), DM+exercise (EX), DM+OPE +EX, and DM+MET. The administration was once daily through the oral route and lasted for 28 days. EX and OPE synergistically ameliorated the diabetic-induced increase in fasting blood sugar, homeostatic model assessment for insulin resistance (HOMA IR), total cholesterol (TC) and triglyceride (TG), TC/high-density lipoprotein (HDL), TG/HDL, triglyceride glucose (TyG) index, and hepatic lactate dehydrogenase, alanine transaminase, malondialdehyde, c-reactive protein, and tumour necrosis factor α when compared with the diabetic untreated group. Also, EX+OPE blunted DM-induced decrease in serum insulin, homeostasis model assessment of β-cell function (HOMA-B), homeostasis model assessment of insulin sensitivity (HOMA S), quantitative insulin-sensitivity check index (QUICK 1), HDL, total antioxidant capacity, superoxide dismutase, and hepatic glycogen. Furthermore, EX+OPE ameliorated the observed DM-induced decrease in glucose transporter type 4 (GLUT 4), expression. This study showed that OPE and EX synergistically ameliorate T2DM-induced dysglycaemia, dyslipidaemia, and down-regulation of GLUT4 expression.

Effect of Pesticide Vinclozolin Toxicity Exposure on Cardiac Oxidative Stress and Myocardial Damage

(1) Background: Vinclozolin is a popular fungicide used in fruit, ornamental plants, and vegetable crops. It has recently been seen that prolonged exposure to VZN can cause human or animal health damage to various organs, but little is known to date about its cardiovascular effects. In this study, we addressed the chronic effects of VZN on the myocardium and the enzymes involved in the cardiovascular function. (2) Methods: The animals were divided into four groups: group 1 served as the control, group 2 received 1 mg/kg of VZN by gavage, group 3 received 30 mg/kg of VZN by gavage, and group 4 received 100 mg/kg of VZN by gavage, for 30 days. (3) Results: Results showed that 100 mg/kg VZN markedly increased the plasma concentration of cardiac markers (CK-MB, cTnT, ANP, BNP). Moreover, compared to the control group, VZN treatment decreased the activity of SOD, CAT, and GPx, and downregulated the mRNA expression levels of Nrf2. Furthermore, collagen deposition was amplified owing to 100 mg/kg VZN cardiotoxicity. This harmful effect was confirmed by a histological study using hematoxylin and eosin (H&E) and Masson's trichrome staining. (4) Conclusion: Overall, our results proved the cardiotoxicity caused by chronic exposure to VZN.

Combinatory Effect and Modes of Action of Chrysin and Bone Marrow-Derived Mesenchymal Stem Cells on Streptozotocin/Nicotinamide-Induced Diabetic Rats

The purpose of this study was to see how chrysin and/or bone marrow-derived mesenchymal stem cells (BM-MSCs) affected streptozotocin (STZ)/nicotinamide (NA)-induced diabetic rats as an animal model of type 2 diabetes mellitus (T2DM). Male Wistar rats were given a single intraperitoneal (i.p.) injection of 60 mg STZ/kg bodyweight (bw) 15 min after an i.p. injection of NA (120 mg/kg bw) to induce T2DM. The diabetic rats were given chrysin orally at a dose of 100 mg/kg bw every other day, BM-MSCs intravenously at a dose of 1 × 10⁶ cells/rat/week, and their combination for 30 days after diabetes induction. The rats in the diabetic group displayed impaired oral glucose tolerance and a decrease in liver glycogen content and in serum insulin, C-peptide, and IL-13 levels. They also had significantly upregulated activities in terms of liver glucose-6-phosphatase and glycogen phosphorylase and elevated levels of serum free fatty acids, IL-1β, and TNF-α. In addition, the diabetic rats exhibited a significant elevation in the adipose tissue resistin protein expression level and a significant decrease in the expression of adiponectin, insulin receptor-beta subunit, insulin receptor substrate-1, and insulin receptor substrate-2, which were associated with a decrease in the size of the pancreatic islets and in the number of β-cells and insulin granules in the islets. The treatment of diabetic rats with chrysin and/or BM-MSCs significantly improved the previously deteriorated alterations, with chrysin combined with BM-MSCs being the most effective. Based on these findings, it can be concluded that combining chrysin with BM-MSCs produced greater additive therapeutic value than using them separately in NA/STZ-induced T2DM rats.

Increasing the added value of vine-canes as a sustainable source of phenolic compounds: A review

Grapes represent one of the most produced fruit crops around the world leading to the generation of large amounts of vine-canes as a side product, with no current economically profitable application. However, vine-canes have been demonstrated to be natural sources of phenolic compounds with numerous health benefits associated, with several potential applications. Therefore, new ambitious applications focused on their re-use are needed, targeting a sustainable process that simultaneous produces functional products and mitigates the waste generation. This review gives to the readers a complete summary about the state of the art regarding the vine-canes extracts research. Vine-canes phenolic composition is addressed and related to the health benefits exhibited. This review comprises studies from the past two decades reporting the extraction processes to recover vine-cane phenolic compounds, including conventional and environmentally friendly technologies and discussing their advantages and disadvantages. The conditions that favour the extraction process for vine-cane polyphenols for each technique were also deeply explored for the first time, enabling to the reader apply only the best parameters to achieve the highest yields without huge investment in optimizations procedures. Furthermore, a correlation between the bioactive properties of the vine-cane extracts and their applications in multiple fields is also critically presented.

Punicalagin Protects against Diabetic Liver Injury by Upregulating Mitophagy and Antioxidant Enzyme Activities

Diabetic liver injury has received increasing attention as a serious complication of type 2 diabetes. Punicalagin (PU), a major component of pomegranate polyphenols, has various biological activities such as antioxidant, anti-inflammatory, and lipid metabolism regulation. In this study, we observed the protective effect of punicalagin on a high-fat diet (HFD) and streptozotocin (STZ)-induced diabetic liver injury in mice and revealed the underlying mechanism. The results showed that fasting blood glucose (FBG), fasting serum insulin (FINS), and homeostasis model assessment for insulin resistance (HOMA-IR) in diabetic liver injury mice were significantly decreased after punicalagin intervention. Simultaneously, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), free fatty acids (FFA), malondialdehyde (MDA), and total superoxide dismutase (T-SOD) in the serum and liver were significantly decreased, with reductions in fat lesions and inflammatory cells. Mitophagy is a selective autophagy that maintains a balance between the quality and quantity of intracellular mitochondria. Studies have shown that mitophagy is closely related to the occurrence and development of diabetic liver injury. In our study, the mitochondrial membrane potential (MMP) was significantly increased in mice with diabetic liver injury after punicalagin intervention; the protein expression of Pink1, Parkin, Bnip3, LC3b, P62, manganese superoxide dismutase (MnSOD), and catalase (CAT) was significantly increased in the liver; and the activities of MnSOD and CAT in the serum and liver were significantly increased, which is consistent with the results of in vitro experiments. In summary, our study provided evidence that punicalagin could reduce the level of oxidative stress in the liver by upregulating mitophagy and the activities of antioxidant enzymes, thus having a certain protective effect against diabetic liver injury.

Naringenin as a natural immunomodulator against T cell-mediated autoimmune diseases: literature review and network-based pharmacology study

T cells, especially CD4+ T helper (Th) cells, play a vital role in the pathogenesis of specific autoimmune diseases. Naringenin, a citrus flavonoid, exhibits anti-inflammatory, anti-oxidant, and antitumor properties, which have been verified in animal autoimmune disease models. However, naringenin's possible effects and molecular mechanisms in T cell-mediated autoimmune diseases are unclear. This review summarizes the findings of previous studies and predicts the target of naringenin in T cell-mediated autoimmune disorders such as multiple sclerosis, inflammatory bowel disease, and rheumatoid arthritis through network pharmacology analysis. We performed DAVID enrichment analysis, protein-protein interaction analysis, and molecular docking to predict the positive effect of naringenin on T cell-mediated autoimmune disorders. Sixteen common genes were screened, among which the core genes were PTGS2, ESR1, CAT, CASP3, MAPK1, and AKT1. The possible molecular mechanism relates to HIF-1, estrogen, TNF, and NF-κB signaling pathways. Our findings have significance for future naringenin treatment of T cell-mediated autoimmune diseases.

Naringenin and Phytoestrogen 8-Prenylnaringenin Protect against Islet Dysfunction and Inhibit Apoptotic Signaling in Insulin-Deficient Diabetic Mice

It has been shown that citrus flavanone naringenin and its prenyl derivative 8-prenylnaringenin (8-PN) possess various pharmacological activities in in vitro and in vivo models. Interestingly, it has been proposed that prenylation can enhance biological potentials, including the estrogen-like activities of flavonoids. The objective of this study was to investigate the anti-diabetic potential and molecular mechanism of 8-PN in streptozotocin (STZ)-induced insulin-deficient diabetic mice in comparison with naringenin reported to exhibit hypoglycemic effects. The oral administration of naringenin and 8-PN ameliorated impaired glucose homeostasis and islet dysfunction induced by STZ treatment. These protective effects were associated with the suppression of pancreatic β-cell apoptosis and inflammatory responses in mice. Moreover, both naringenin and 8-PN normalized STZ-induced insulin-signaling defects in skeletal muscles and apoptotic protein expression in the liver. Importantly, 8-PN increased the protein expression levels of estrogen receptor-α (ERα) in the pancreas and liver and of fibroblast growth factor 21 in the liver, suggesting that 8-PN could act as an ERα agonist in the regulation of glucose homeostasis. This study provides novel insights into the mechanisms underlying preventive effects of naringenin and 8-PN on the impairment of glucose homeostasis in insulin-deficient diabetic mice.

Protective efficacy of naringenin against cadmium-induced redox imbalance in Labeo rohita: an integrated biomarker approach

The protective efficacy of dietary naringenin (NG) has been investigated against the toxicity caused by cadmium chloride (CdCl₂) using biomarkers of oxidative stress in the liver, gills and kidney of Labeo rohita. The fish were exposed to environmentally relevant concentrations of CdCl₂ (0.37 and 0.62 mg/L) and simultaneously orally administered with NG (50 mg/kg bw/day) for 60 days. Tissue (gills, liver and kidney) samples were collected on days 15, 30 and 60 of the experiment and analysed for endogenous antioxidants and oxidative stress biomarkers. CdCl₂ exposure for 15 and 30 days induced the development of adaptive mechanism as demonstrated by the enhanced activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione-S-transferase in all three tissues. However, on the 60th day, CdCl₂-induced oxidative damage was stipulated by a decline in the enzyme activities and reduced glutathione (GSH) content significantly (p < 0.05) below control levels along with enhanced levels of lipid peroxidation. Oral administration of NG in toxicant exposed fish significantly restored the altered levels of antioxidants, oxidative enzymes and lipid peroxidation. Besides, integrated biomarker response (IBR) analysis was applied by combining all the biomarkers to indicate the overall stress response index. IBR analysis confirmed the altered levels of biomarkers, the oxidative stress induced by CdCl₂ exposure and the ameliorative potential of NG. The present study suggested that NG might have protective role against Cd-induced oxidative insult which might be ascribed to the ability of NG to chelate metals and scavenge free radicals.

Endoplasmic reticulum stress-dependent activation of TRB3-FoxO1 signaling pathway exacerbates hyperglycemic nephrotoxicity: Protection accorded by Naringenin

Endoplasmic reticulum (ER) dysfunction contributes greatly to the pathophysiology of hyperglycemic nephrotoxicity. This study unravels the critical role of Tribbles 3 (TRB3)-Forkhead box O1 (FoxO1) signaling pathway during hyperglycemic renal toxicity. It also uncovers the novel role of Naringenin, a flavanone, in regulating ER stress in proximal tubular cells, NRK 52E, and kidneys of streptozotocin/nicotinamide induced experimental diabetic Wistar rats. Results demonstrate that expression of ER stress marker proteins including phosphorylated protein kinase ER like kinase (p-PERK), phosphorylated eukaryotic Initiation Factor 2α (p-eIF2α), X Box Binding Protein 1 spliced (XBP1s), Activating Transcription Factor 4 (ATF4) and C/EBP Homologous Protein (CHOP) were upregulated in diabetic kidneys indicating the activation of ER stress response due to nephrotoxicity. Treatment with Naringenin reduced the expression of TRB3, an ER stress-inducible pseudokinase, both in vitro and in vivo. Gene silencing of TRB3 enhanced Akt and FoxO1 phosphorylation and alleviated FoxO1 mediated apoptosis during hyperglycemic nephrotoxicity. Notably, TRB3 gene silencing effects were comparable to the response with Naringenin treatment. Prevention of nuclear colocalization of ATF4 and CHOP in Naringenin treated cells was evident. Naringenin also reduced insulin resistance, apoptosis and glycogen accumulation along with enhancement of glucose tolerance in diabetic rats. Prevention of ultrastructural aberrations in the ER of hyperglycemic renal cells by Naringenin confirmed its anti-ER stress effects. These findings affirm that activation of TRB3-FoxO1 signaling is critical in the pathogenesis of hyperglycemia-induced renal toxicity and protective effect of Naringenin via modulation of ER stress may be exploited as a novel approach for its management.

Meta-analysis Flavonoids from traditional Chinese herbs for diabetes in rats: a network Meta-analysi

OBJECTIVE

In this Meta-analysis, we evaluated the hypoglycemic effect of 5 flavonoids found in traditional Chinese herbs (naringenin, kaempferol, puerarin, baicalein, and luteolin) on diabetic rats.

METHODS

Four databases including PubMed, Web of Science, Embase, and Cochrane Library, were searched from inception to May 2020. Only studies using diabetes model rats were included in the analysis. Blood glucose data from the last measurement were collected and analyzed. Pair-wise Meta-analyses were conducted using STATA v14.0 software and a Meta-analysis was conducted using STATA v14.0, ADDIS v1.16.6, and R v3.6.1. The quality of included studies was assessed with the SYRCLE risk of bias tool for animal studies, and publication bias was evaluated with a comparisonadjusted funnel plot.

RESULTS

A total of 33 studies were included in the analysis, in which all 5 flavonoids showed a beneficial effect on blood glucose level of diabetic rats were included in the final analysis. The standardized mean differences (95% confidence intervals) were -4.92 (-6.67, -3.17) fornaringenin, -12 (-18.74, -5.27) for kaempferol, -2.52 (-3.77, -1.26) for puerarin, -3.04 (-5.75, -0.34) for baicalein, and -1.94 (-2.95, -0.92) for luteolin. The network Meta-analysis showed no statistically significant differences between the effect sizes of the flavonoids.

CONCLUSION

The results of the Meta-analysis showed that naringenin, kaempferol, puerarin, baicalein, and luteolin all have clear hypoglycemic effects in rat diabetes models, highlighting their therapeutic potential for preventing and treating diabetes mellitus in clinical practice.

Simultaneous Modulation of NLRP3 Inflammasome and Nrf2/ARE Pathway Rescues Thioacetamide-Induced Hepatic Damage in Mice: Role of Oxidative Stress and Inflammation

Chronic tissue injury resulting in fibrosis of multiple organs, responsible for one-third of the death globally. Liver fibrosis is a common pathway/condition involved in all chronic liver diseases. Thioacetamide (TAA), a hepatotoxicant, was used to induce hepatic fibrosis. Anti-diabetic drug glibenclamide (GLB) possesses anti-inflammatory properties and inhibits NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome activation. Dimethyl fumarate (DMF), a multiple sclerosis drug, activates the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway and maintains the antioxidant status in the cell. The present study was designed to investigate (i) role of NLRP3 inflammasome and Nrf2/ARE pathway in TAA-induced hepatotoxicity and liver fibrosis, (ii) mechanism involved in GLB and DMF mediated hepatoprotection against TAA-induced hepatotoxicity, and (iii) additional/synergistic hepatoprotective effect of combination treatment with NLRP3 inhibition + Nrf2 activation or GLB + DMF or MCC950 + 4OI to reverse/ameliorate the experimental liver fibrosis completely. TAA was administered intraperitoneally to mice for seven consecutive weeks, and treatments of GLB, DMF, GLB + DMF, MCC950, 4OI, and MCC950 + 4OI were provided for the last three consecutive weeks. The intervention with GLB, DMF, GLB + DMF, MCC950, 4OI, and MCC950 + 4OI significantly protected TAA-induced oxidative stress and inflammatory conditions by improving biochemical, histological, and immunoexpression changes in mice. The GLB, DMF, and GLB + DMF intervention exhibited a better protective effect compared with MCC950, 4OI, and MCC950 + 4OI, which revealed that this specific inhibitor/activator possesses only NLRP3 inflammasome inhibitory/Nrf2 activatory properties. In contrast, the clinical drug GLB and DMF have several other beneficial effects, which are independent of NLRP3 inhibition and Nrf2 activation.

Naringenin alleviates hyperglycemia-induced renal toxicity by regulating activating transcription factor 4-C/EBP homologous protein mediated apoptosis

Endoplasmic reticulum (ER) dysfunction plays a prominent role in the pathophysiology of diabetic nephropathy (DN). This study aimed to investigate the novel role of Naringenin (a flavanone mainly found in citrus fruits) in modulating ER stress in hyperglycemic NRK 52E cells and STZ/nicotinamide induced diabetes in Wistar rats. The results demonstrated that Naringenin supplementation downregulated the expression of ER stress marker proteins, including p-PERK, p-eIF2α, XBP1s, ATF4 and CHOP during hyperglycemic renal toxicity in vitro and in vivo. Naringenin abrogated hyperglycemia-induced ultrastructural changes in ER, evidencing its anti-ER stress effects. Interestingly, treatment of Naringenin prevented nuclear translocation of ATF4 and CHOP in hyperglycemic renal cells and diabetic kidneys. Naringenin prevented apoptosis in hyperglycemic renal cells and diabetic kidney tissues by downregulating expression of apoptotic marker proteins. Further, photomicrographs of TEM confirmed anti-apoptotic potential of Naringenin as it prevented membrane blebbing and formation of apoptotic bodies in hyperglycemic renal cells. Naringenin improved glucose tolerance, restored serum insulin level and reduced serum glucose level in diabetic rats evidencing its anti-hyperglycemic effects. Histopathological examination of kidney tissues also confirmed prevention of damage after 28 days of Naringenin treatment in diabetic rats. Additionally, Naringenin diminished oxidative stress and improved antioxidant defense response during hyperglycemic renal toxicity. Taken together, our study revealed a novel role of Naringenin in ameliorating ER stress during hyperglycemic renal toxicity along with prevention of apoptosis, cellular and tissue damage. The findings suggest that prevention of ER stress can be exploited as a novel approach for the management of hyperglycemic nephrotoxicity.

The Role of Selected Natural Biomolecules in Sperm Production and Functionality

Emerging evidence from in vivo as well as in vitro studies indicates that natural biomolecules may play important roles in the prevention or management of a wide array of chronic diseases. Furthermore, the use of natural compounds in the treatment of male sub- or infertility has been proposed as a potential alternative to conventional therapeutic options. As such, we aimed to evaluate the effects of selected natural biomolecules on the sperm production, structural integrity, and functional activity. At the same time, we reviewed their possible beneficial or adverse effects on male reproductive health. Using relevant keywords, a literature search was performed to collect currently available information regarding molecular mechanisms by which selected natural biomolecules exhibit their biological effects in the context of male reproductive dysfunction. Evidence gathered from clinical trials, in vitro experiments and in vivo studies suggest that the selected natural compounds affect key targets related to sperm mitochondrial metabolism and motion behavior, oxidative stress, inflammation, DNA integrity and cell death. The majority of reports emphasize on ameliorative, stimulating and protective effects of natural biomolecules on the sperm function. Nevertheless, possible adverse and toxic behavior of natural compounds has been indicated as well, pointing out to a possible dose-dependent impact of natural biomolecules on the sperm survival and functionality. As such, further research leading to a deeper understanding of the beneficial or adverse roles of natural compounds is necessary before these can be employed for the management of male reproductive dysfunction.

Recent Progress in Environmental Toxins-Induced Cardiotoxicity and Protective Potential of Natural Products

Humans are unconsciously exposed to environmental toxins including heavy metals as well as various pesticides, which have deleterious effects on human health. Accumulating studies pointed out that exposure to environmental toxins was associated with various cardiopathologic effects. This review summarizes the main mechanisms of cardiotoxicity induced by environmental toxins (cadmium, arsenic and pesticides) and discusses the potential preventive effects of natural products. These findings will provide a theoretical basis and novel agents for the prevention and treatment of environmental toxins-induced cardiotoxicity. Furthermore, the limitations of current studies, future needs and priorities are discussed.

Phytochemical and Ethnopharmacological Perspectives of Ehretia laevis

Ehretia laevis Roxb. (Boraginaceae) has been extensively used as a traditional remedy for the treatment of a diverse range of ailments related to the respiratory system, the gastrointestinal tract, the reproductive system, and against several infections. This review critically assesses and documents, for the first time, the fragmented information on E. laevis, including its botanical description, folklore uses, bioactive phyto metabolites and pharmacological activities. The goal is to explore this plant therapeutically. Ethnomedicinal surveys reveal that E. laevis has been used by tribal communities in Asian countries for the treatment of various disorders. Quantitative and qualitative phytochemical investigations of E. laevis showed the presence of important phytoconstituents such as pentacyclic triterpenoids, phenolic acids, flavonoids, fatty acids, steroids, alkaloids, aliphatic alcohols, hydrocarbons, amino acids, carbohydrates, vitamins and minerals. Fresh plant parts, crude extracts, fractions and isolated compounds have been reported to exhibit broad spectrum of therapeutic activities viz., antioxidant, antiarthritic, antidiabetic, anti-inflammatory, antiulcer, antidiarrheal, antidysenteric, wound healing and anti-infective activities. E. laevis is shown to be an excellent potential source of drugs for the mitigation of jaundice, asthma, dysentery, ulcers, diarrhea, ringworm, eczema, diabetes, fissure, syphilis, cuts and wounds, inflammation, liver problems, venereal and infectious disorders. Although few investigations authenticated its traditional uses but employed uncharacterized crude extracts of the plant, the major concerns raised are reproducibility of therapeutic efficacy and safety of plant material. The outcomes of limited pharmacological screening and reported bioactive compounds of E. laevis suggest that there is an urgent need for in-depth pharmacological investigations of the plant.

PHLPP1/Nrf2-Mdm2 axis induces renal apoptosis via influencing nucleo-cytoplasmic shuttling of FoxO1 during diabetic nephropathy

Impaired PI3K/Akt signaling (insulin resistance) and poor glycemic control (hyperglycemia) are the major risk factors involved in the progression of diabetic nephropathy (DN). This study was designed to identify factors influencing cell survival during DN. We found that high glucose exposure in renal proximal tubular cells (NRK52E) upregulated PHLPP1, an Akt phosphatase (Ser473), causing suppression in Akt and IGF1β phosphorylation leading to inhibition in insulin signaling pathway. Results demonstrate that sustained activation of PHLPP1 promoted nuclear retention of FoxO1 by preventing its ubiquitination via Mdm2, an Akt/ Nrf2-dependent E3 ligase. Thus, enhanced FoxO1 nuclear stability caused aberration in renal gluconeogenesis and activated apoptotic cascade. Conversely, gene silencing of PHLPP1-enhanced Nrf2 expression and attenuated FoxO1 regulated apoptosis compared to hyperglycemic cells. Mechanistic aspects of PHLPP1-Nrf2/FoxO1 signaling were further validated in STZ-nicotinamide-induced type 2 diabetic Wistar rats. Importantly, we observed via immunoblotting and dual immunocytochemical studies that treatment of Morin (2',3,4',5,7-Pentahydroxyflavone) during diabetes significantly augmented FoxO1 nuclear exclusion, resulting in its ubiquitination via Akt-Nrf2/Mdm2 pathway. Furthermore, lowering of PHLPP1 expression by Morin also prevented FoxO1/Mst1-mediated apoptotic signaling in vitro and in vivo. Morin treatment under the experimental conditions, effectively decreased blood glucose levels, ameliorated insulin resistance, alleviated oxidative stress and attenuated renal apoptosis in diabetic rats comparable to metformin thereby exhibiting tremendous potential against renal complications of diabetes. These novel results further acclaim that inhibition of PHLPP1/FoxO1-Mdm2 axis is critical in the pathogenesis of diabetic nephropathy.

Hesperidin and Naringin Improve Broiler Meat Fatty Acid Profile and Modulate the Expression of Genes Involved in Fatty Acid β-oxidation and Antioxidant Defense in a Dose Dependent Manner

The beneficial properties of the flavanones hesperidin and naringin as feed additives in poultry have lately been under investigation. In broilers, both flavanones have been shown to exhibit antioxidant properties while their individual effects on fatty acid (FA) composition and the underlying molecular mechanisms of their activity have not been explored. Here, we studied their effects on broiler meats' FA profiles and on the expression of genes related to lipid metabolism, antioxidant defense and anti-inflammatory function. The experimental design comprised six treatment groups of broilers, each supplemented from day 11 until slaughter at 42 days with hesperidin, naringin or vitamin E, as follows: the E1 group received 0.75 g of hesperidin per kg of feed, E2 received 1.5 g hesperidin/kg feed, N1 received 0.75 g naringin/kg feed, N2 received 1.5 g naringin/kg feed, vitamin E (VE) received 0.2 g a-tocopheryl acetate/kg feed, and the control group was not provided with a supplemented feed. The VE treatment group served as a positive control for antioxidant activity. An analysis of the FA profiles of the abdominal adipose tissue (fat pad), major pectoralis (breast) and biceps femoris (thigh) muscles showed that both hesperidin and naringin had significant effects on saturated FA (SFA), polyunsaturated FA (PUFA) and omega n-6 content. Both compounds reduced SFA and increased PUFA and n-6 content, as well as reducing the atherogenicity and thrombogenicity indices in the breast muscle and fat pad. The effects on the thigh muscle were limited. An analysis of gene expression in the liver revealed that naringin significantly increased peroxisome proliferator-activated receptor alpha (PPARα), Acyl-CoA oxidase 1 (ACOX1) and glutathione disulfide reductase (GSR) expression. In the breast muscle, both hesperidin and naringin increased fatty acid synthase (FASN) expression and hesperidin increased the expression of adiponectin. In brief, both hesperidin and naringin supplementation beneficially affected FA profiles in the breast meat and fat pad of broiler chicken. These effects could be attributed to an increase in FA β-oxidation since the increased expression of related genes (PPARα and ACOX1) was observed in the liver. Furthermore, the antioxidant activity of hesperidin and naringin previously observed in the meat of broilers could be attributed, at least partly, to the regulation of antioxidant defense genes, as evidenced by the increased GSR expression in response to naringin supplementation.

Effect of crocin and naringenin supplementation in cryopreservation medium on post-thaw rooster sperm quality and expression of apoptosis associated genes

The aim of our study was to examine the effects of crocin (0.5 (C0.5), 1 (C1) and 1.5 (C1.5) mM) and naringenin (50 (N50), 100 (N100) and 150 (N150) μM) in cryopreservation extender for freezing rooster semen. Sperm motility, viability, abnormalities, membrane functionality, active mitochondria, apoptosis status, lipid peroxidation (LP), GPX, SOD, TAC, the mRNA expression of pro-apoptotic (CASPASE 3) and anti-apoptotic (Bcl-2) genes, fertile eggs, hatched eggs and hatching rate were investigated following freeze-thawing. C1 and N100 resulted in higher (P < 0.05) total motility and progressive motility in comparison to the control group. The C1 and N100 groups improved viability, membrane functionality and reduced lipid peroxidation. We found higher values for active mitochondria with C1 and N100 compared to control group. The C1 and N100 groups showed lower percentages of early apoptosis when compared with control group. Also, C1 and N100 had higher TAC, compared to the control group. The mRNA expressions of BCL-2 in the C1 and N100 groups were significantly higher than that of other treatments. The expression of CASPASES 3 was significantly reduced in C1 and N100 group (P < 0.05) when compared to control group. Significantly higher percentages of fertile eggs, hatched eggs and hatching rate were observed in C1 and N100 compared to the control group. In conclusion, crocin at 1 mM and naringenin at 100 μM seem to improve the post-thawing rooster semen quality, fertility and could protect the sperm by reducing the pro-apoptotic (CASPASE 3) and increasing anti-apoptotic (Bcl-2) genes.

Quercetin and Naringenin Provide Functional and Antioxidant Protection to Stored Boar Semen

In this study, we evaluated the impact of 5-50 μM quercetin (QUE) and naringenin (NAR) on extended boar spermatozoa in the BTS (Beltsville Thawing Solution) medium for 72 h. Spermatozoa motion, membrane, acrosome, and DNA integrity were investigated immediately after sample dilution (0 h) as well as after 24 h, 48 h, and 72 h of semen storage. Furthermore, reactive oxygen species (ROS) and superoxide production, as well as the extent of oxidative damage to the sperm proteins and lipids, were assessed to determine the potential of QUE and NAR to prevent a potential loss of sperm vitality due to oxidative stress development. Our results indicate that the most notable parameter influenced by QUE was the mitochondrial activity, which remained significantly higher throughout the experiment (p < 0.001 and p < 0.0001; 10 μM), and which correlated with the most prominent maintenance of sperm motility (p < 0.01, 48 h; p < 0.05, 72 h). A significant membrane stabilization (p < 0.01, 24 h and 48 h; p < 0.0001, 72 h) and prevention of lipid peroxidation (p < 0.05, 24 h and 48 h; p < 0.01, 72 h) was primarily observed following administration of 10 and 25 μM NAR; respectively. Administration of 10 μM QUE led to a significant decrease of superoxide (p < 0.0001, 48 h and 72 h) while the most notable decline of ROS generation was recorded in the case of 10 and 25 μM NAR (p < 0.001). This study may provide new information on the specific mechanisms of action involved in the favorable effects of natural biomolecules on spermatozoa.

Chromolaena odorata flavonoids attenuate experimental nephropathy: Involvement of pro-inflammatory genes downregulation

Nephropathy is a serious complication comorbid with a number of life-threatening diseases such as diabetes. Flavonoids are well known cytoprotective phytochemicals. Here, nephropathy associated with streptozotocin (STZ) treatment in experimental animals was challenged by flavonoids (CoF) isolated from Chromolaena odorata. Experimental animals were divided into control (n = 5), STZ (40 mg/kg b.w. i.p. n = 5) and STZ-CoF (CoF = 30 mg/kg b.w. oral, 60 days, n = 7) groups. Blood urea nitrogen (BUN) and serum creatinine (SC) levels were quantified using ELISA. Kidney function, inflammatory marker, and antioxidant gene expression levels were also evaluated using reverse-transcription and polymerase chain reaction protocols. Histological assessment was also performed using Haematoxylin and Eosin (H&E) staining protocols. CoF improved kidney function by restoring BUN/SC levels to pre-STZ treatment states. KIM-1, TNF-α, and MCP-1 but not TNF-R and IL-10 genes were significantly downregulated in STZ-CoF treated group in comparison with STZ-treated group (p < 0.05). Anti-oxidant genes (GPx-1, CAT) significantly (p < 0.05 vs. control) upregulated in STZ-treatment did not respond to CoF treatment. STZ treatment associated Bowman's space enlargement, thickened basement membrane, and glomerulosclerosis were completely reversed in STZ-CoF group. Finally, CoF has demonstrable anti-nephropathic via downregulation of proinflammatory genes and may represent new management option in clinical nephropathy.

Naringin attenuates Bisphenol-A mediated neurotoxicity in hypertensive rats by abrogation of cerebral nucleotide depletion, oxidative damage and neuroinflammation

We examined whether active fruit naringin can reduce the risk of BPA-mediated neurotoxicity in L-NAME induced hypertensive rats and whether the modulation could be linked to improvement of brain NO signaling. Male albino rats were randomly distributed into eight (n = 7) groups. Group I was control animals, Group II was orally-treated with L-NAME, Group III was orally treated with 100 mg/kg BPA, Group IV was orally-treated with L-NAME +100 mg/kg BPA. Group V was orally-administered with L-NAME +80 mg/kg NAR. Group VI was orally-administered with 100 mg/kg BPA +80 mg/kg NAR. Group VII was orally-administered with L-NAME+100 mg/kg BPA +80 mg/kg NAR. Lastly, group VIII was orally-treated with 80 mg/kg NAR. The treatment lasted for 14 days. Sub-acute exposure to L-NAME and BPA induced hypertension and mediated-neuroinflammation at CA-2 and CA-4 of hippocampus cells. It was evident by increase in PDE-5¹ and enzymes of ATP hydrolysis (ATPase, ADPase and AMPase) with corresponding upsurge in cholinergic (AChE and BuChE), dopaminergic (MAO-A) and adenosinergic (ADA) enzymes as well as movement disorder. The hypertensive-mediated neurotoxicity was related to alteration of NO signaling and higher release of pro-inflammatory cytokines (TNF-α and IL-1β), apoptotic proteins (P53 and caspace-9) and facilitated entry of T-lymphocytes (CD43⁺) into CNS through blood brain barrier potentiated by antigen presenting cells. Hence, these features of BPA-mediated neurotoxicity in L-NAME induced hypertensive rats were prohibited by co-administration of NAR through production of neuro-inflammatory mediators, stabilizing neurotransmitter enzymes, normalizing NO signaling and improving brain histology.

Antidiabetic Potency, Antioxidant Effects, and Mode of Actions of Citrus reticulata Fruit Peel Hydroethanolic Extract, Hesperidin, and Quercetin in Nicotinamide/Streptozotocin-Induced Wistar Diabetic Rats

This study is aimed at assessing the antihyperglycemic, antihyperlipidemic, and antioxidant effects of Citrus reticulata (C. reticulata) fruit peel hydroethanolic extract and two flavonoids, hesperidin and quercetin, in nicotinamide (NA)/streptozotocin- (STZ-) induced type 2 diabetic rats. In addition, GC-MS and HPLC-MS analyses of the extract were performed and the results indicated the presence of multiple flavonoids including hesperidin, quercetin, naringin, and polymethoxylated flavones (nobiletin and tangeretin). To achieve the aim of the study, diabetic rats with NA/STZ-induced T2DM were orally treated with C. reticulata fruit peel hydroethanolic extract, hesperidin, and quercetin at a dose of 100 mg/kg b.w./day for four weeks. The treatments with C. reticulata fruit peel extract, hesperidin, and quercetin significantly ameliorated the impaired oral glucose tolerance; the elevated serum fructosamine level; the diminished serum insulin and C-peptide levels; the altered HOMA-IR, HOMA-IS, and HOMA-β cell function; the decreased liver glycogen content; the increased liver glucose-6-phosphatase and glycogen phosphorylase activities; the deleteriously affected serum lipid profile; the elevated serum AST and ALT activities; and the raised serum creatinine and urea levels in the diabetic rats. The treatments also produced remarkable improvement in the antioxidant defense system manifested by a decrease in the elevated liver lipid peroxidation and an increase in the lowered glutathione content and GPx, GST, and SOD activities. Furthermore, the three treatments enhanced the mRNA expression of GLUT-4 and the insulin receptor β-subunit, but only quercetin produced a significant increase in the expression of adiponectin in adipose tissue of diabetic rats. In conclusion, C. reticulata fruit peel hydroethanolic extract, hesperidin, and quercetin have potent antidiabetic effects which may be mediated through their insulinotropic effects and insulin-sensitizing actions. In addition, the alleviation of the antioxidant defense system by the extract, hesperidin, and naringin may have an important action to enhance the antidiabetic actions and to improve liver and kidney functions in NA/STZ-induced diabetic rats.

Phytochemical analysis and in vitro cytostatic potential of ethnopharmacological important medicinal plants

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Murraya koenigii induced higher cytotoxicity in Dalton’s lymphoma through apoptotic cell death as compared to other plants under study.

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The plant extract mediated apoptotic cell death is mediated by ROS generation and caspases activation.

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The study support the ethnomedicinal uses of these plants extracts and suggests further validation in other human cancer cell lines.

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Conservation organization would eventually need to document this indigenous traditional knowledge (TK).

Annonareticulate (Mart.), Lablab purpureus (L.) Sweet, Murrayakoenigii (L.) Spreng, Moringaoleifera (Lam.), Hibiscussabdariffa (L.) and Euphorbiahirta (L.) are most commonly used medicinal plants by the traditional healers of Karbi Anglong district of Assam, India against different human ailments including cancer suspected cases. The proposed study includes field survey related to ethnomedicinal aspects of medicinal plants, phytochemical analysis, and evaluation of their cytostatic potential with the possible mode of action against Dalton's lymphoma (DL) cell line. The phytochemical analysis of all the plant's extract was studied using standard protocol. The cytotoxicity of the methanol extracts was determined by MTT reduction assay. The effect of the same extract was also tested for development of apoptosis features in DL cells using a fluorescence microscope and flowcytometry. The underlying mechanism closely associated with apoptotic cell death was also studied by measuring reactive oxygen species (ROS), mitochondrial membrane potential, and expression level of apoptosis inducing proteins. Murraya koenigii induced more apoptotic features in DL cells, followed by Annona reticulate. The decrease in mitochondrial membrane potential, release of cytochrome- c, increase in ROS level and higher expression of caspases (3 and 9) after plant extracts treatment may cause involvement of mitochondria in the process of apoptosis. From this study, it can be concluded that the plant species mainly Murraya koenigi and Annona reticulate significantly induced cytotoxicity in DL cells through apoptosis by utilizing mitochondrial pathway.

The possible alleviating effect of saffron on chlorpyrifos experimentally induced cardiotoxicity: Histological, immunohistochemical and biochemical study

INTRODUCTION

Pesticides are responsible for many occupational health hazards among farmers in developing countries. Chlorpyrifos (CPF) is one of the broad-spectrum organophosphorus (OP) insecticides used for agricultural, domestic and industrial purposes.

AIM OF THE WORK

The present study was designed to examine the effects of CPF on cardiac muscles and to evaluate the possible protective role of crocin using biochemical and histological methods with the intention to recognize the molecular tools of its probable cardioprotective effects.

MATERIALS AND METHODS

Thirty-six adult male albino rats were used in this study and were divided into 4 equal groups (9 rats each): negative control group, positive control group, CPF treated group and CPF & crocin treated group. The heart was removed for histological and immunohistochemical studies.

RESULTS

Stained sections of cardiac muscle fibers of group III with H&E revealed remarkable histological changes in the form of disorganization of the fibers with increase in the interstitial spaces between these fibers. Congested dilated blood capillaries could be observed with extravasation of the red blood cells leading to interstitial hemorrhage. Focal areas of mononuclear cellular infiltration could be seen in the interstitial tissue. A number of cardiac fibers achieved pale acidophilic vacuolated sarcoplasm while others achieved dark homogenous acidophilic sarcoplasm. Some nuclei were peripherally situated and pyknotic while others were centrally situated and encircled with halos. Apparently increased masses of collagen fibers among the cardiac muscle fibers and around the congested dilated blood vessels with the presence of focal parts of extensive collagen fiber deposition were noticed in Mallory-stained sections of group III. Strong positive immunoreactions in the endomysium and perimysium of the cardiac fibers, along with the walls of blood capillaries and in interstitial cells, could be detected in immunohistochemical staining sections of group III with vimentin antibody. Immunoreactivity to caspase 3 was higher in the sarcoplasm of the cardiac fibers of group III compared to that of control group. A highly significant decrease in the cardiac level of SOD and CAT; however, a highly significant increase in MDA level was noted between the control groups and CPF treated group. Additionally, there was a significant improvement of the chemical and histological representations of group IV, and these improvement pictures were toward the normal.

CONCLUSION

The study concludes that crocin can alleviate the toxic effect of chlorpyrifos caused by oxidative stress on cardiac muscle.

Antidiabetic Properties of Naringenin: A Citrus Fruit Polyphenol

Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by insulin resistance and hyperglycemia and is associated with personal health and global economic burdens. Current strategies/approaches of insulin resistance and T2DM prevention and treatment are lacking in efficacy resulting in the need for new preventative and targeted therapies. In recent years, epidemiological studies have suggested that diets rich in vegetables and fruits are associated with health benefits including protection against insulin resistance and T2DM. Naringenin, a citrus flavanone, has been reported to have antioxidant, anti-inflammatory, hepatoprotective, nephroprotective, immunomodulatory and antidiabetic properties. The current review summarizes the existing in vitro and in vivo animal studies examining the anti-diabetic effects of naringenin.

Effects and Underlying Mechanisms of Bioactive Compounds on Type 2 Diabetes Mellitus and Alzheimer's Disease

Type 2 diabetes mellitus is a complicated metabolic disorder characterized by hyperglycemia and glucose intolerance. Alzheimer's disease is a progressive brain disorder characterized by a chronic loss of cognitive and behavioral function. Considering the shared characteristics of both diseases, common therapeutic and preventive agents may be effective. Bioactive compounds such as polyphenols, vitamins, and carotenoids found in vegetables and fruits can have antioxidant and anti-inflammatory effects. These effects make them suitable candidates for the prevention or treatment of diabetes and Alzheimer's disease. Increasing evidence from cell or animal models suggest that bioactive compounds may have direct effects on decreasing hyperglycemia, enhancing insulin secretion, and preventing formation of amyloid plaques. The possible underlying molecular mechanisms are described in this review. More studies are needed to establish the clinical effects of bioactive compounds.

Effects of citral on oxidative stress and hepatic key enzymes of glucose metabolism in streptozotocin/high-fat-diet induced diabetic dyslipidemic rats

OBJECTIVES

Phytochemicals such as polyphenols, alkaloids, and terpenoids, protect against the development of early stages and complications of diabetes mellitus according to various reports. The aim of this study was to measure the anti-dyslipidemic and anti-diabetic effects of Citral on high-fat-diet (HFD) and streptozotocin (STZ) induced diabetic dyslipidemic rats and to see also its effect on carbohydrate metabolic regulatory enzymes in the liver.

MATERIALS AND METHODS

Rats were kept on a high-fat diet for 2 weeks, then diabetes was induced by a single dose of STZ (35 mg/kg/BW, intraperitoneally), Citral was administered orally at a dose of 45 mg/kg/BW for 28 days to diabetic rats. Blood glucose, plasma insulin, and lipid profile in blood were studied. Antioxidant activities were assayed in the liver, pancreas, and adipose tissues. Carbohydrate metabolic enzymes of the liver were also studied in diabetic dyslipidemic rats.

RESULTS

The results of this study confirmed that administration of Citral significantly (P<0.05) decreased the blood glucose level and increased plasma insulin in diabetic rats. Citral also improved oxidative markers along with anti-oxidative enzymes of the liver, adipose tissue, and pancreas in the HFD/STZ group. Citral also regulated the activity of the glucose-metabolic enzymes in the liver. The results of the present study were compared to Glibenclamide, which is a standard oral drug for lowering the blood sugar.

CONCLUSION

Results may show that Citral possesses anti-dyslipidemic activity as well as anti-diabetic activity and also regulates the enzyme activity of glycolytic and gluconeogenic processes in the liver.

Potential protective effects of naringenin against vancomycin-induced nephrotoxicity via reduction on apoptotic and oxidative stress markers in rats

Vancomycin (VCM), a glycopeptide antibiotic, is a drug widely used in severe infections. However, VCM induce notable nephrotoxic side effects. Naringenin (NAR) is a natural of flavonoid and are known as strongly antioxidant, nefroprotective, antiapoptotic, and anti-inflammatory. The purpose of this study was to determine the potential protective effects of NAR against VCM-induced nephrotoxicity by measuring apoptotic and oxidative stress markers and evaluating histopathological alterations in rats. For this purpose, we used male Wistar albino rats that divided into seven groups: (i) Control [saline, intraperitoneally (i.p.)], (ii) carboxymethyl cellulose (0.5% CMC, orally), (iii) VCM (400 mg/kg, i.p.), (iv) NAR100 (100 mg/kg, orally), (v) VCM + NAR25 (25 mg/kg, orally), (vi) VCM + NAR50 (50 mg/kg, orally), and (vii) VCM + NAR100 (100 mg/kg, orally) groups. VCM administration was started one day after the first treatment of NAR and continued across 7-day. Caspase-3, -8, and-9 activities and malondialdehyde (MDA) and nitric oxide (NO) levels were measured by colorimetric methods in the kidney tissues, creatinine, and blood urea nitrogen (BUN) levels were analyzed based on ELISA in serum. Caspase-3 and -8 activities, NO levels, serum creatinine and BUN levels were significantly higher in VCM group in comparison with VCM + NAR (25, 50, and 100) groups (p < 0.05). Caspase-9 activity and MDA were significantly higher in VCM group compared to VCM + NAR (25 and 50) groups (p < 0.05). Histopathological alterations in VCM group were significantly diminished by administration of NAR, especially NAR 25. In conclusion, NAR 25 and 50 mg have more potent protective effects on VCM-induced nephrotoxicity compared to NAR 100 mg.

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.

Hesperetin, a citrus flavonoid, attenuates testicular damage in diabetic rats via inhibition of oxidative stress, inflammation, and apoptosis

AIM

This study was designed to assess the beneficial effect of hesperetin on diabetes-associated testicular injury in the rat.

MAIN METHODS

Oral treatment with hesperetin started 10 days after diabetes induction by streptozotocin (60 mg/kg, i.p.) for 46 days. Testicular damage was evaluated by histological evaluation of seminiferous tubules in addition to assessment of epididymal sperm count, motility, and viability. In addition, testicular biomarkers of apoptosis, inflammation, and oxidative stress were also determined.

KEY FINDINGS

Hesperetin treatment of diabetic group prevented body weight loss and reduced serum glucose in addition to improvement of serum testosterone. Additionally, hesperetin-treated diabetic group had lower levels of malondialdehyde (MDA), reactive oxygen species (ROS), protein carbonyl, DNA fragmentation, and caspase 3 activity as specific biomarkers of oxidative stress and/or apoptosis. Furthermore, hesperetin augmented testicular antioxidant system as shown by higher levels of glutathione (GSH), mitochondrial membrane potential (MMP), and ferric reducing antioxidant power (FRAP) in addition to improvement of superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPx). Moreover, hesperetin administration to diabetic rats attenuated testicular indices of inflammation consisting of tumor necrosis factor α (TNFα) and interleukin 17 (IL-17) and prevented damage of seminiferous tubules as revealed by higher levels of sperm count, motility, and viability in diabetic rats.

SIGNIFICANCE

Collectively, hesperetin could alleviate testicular damage in DM, at least through inhibition of apoptosis, oxidative stress, and inflammation in addition to its up-regulation of endogenous enzymatic and non-enzymatic antioxidants.

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.

Navel orange peel hydroethanolic extract, naringin and naringenin have anti-diabetic potentials in type 2 diabetic rats

The therapy of Type 2 Diabetes Mellitus (T2DM) stays a challenging issue. During the last decade, there has been an interest in the expansion of anti-diabetic drugs especially those of natural sources. Thus, the aim of this study was to assess the anti-hyperglycemic and the anti-hyperlipidemic effects as well as the anti-oxidant activities of navel orange hydroethanolic extract and its constituting flavonoids naringin and naringenin on nicotineamide (NA)/streptozotocin (STZ)-induced type 2 diabetic rats. To induce T2DM, 16h-fasted rats were intraperitoneally injected with STZ at dose of 50mg/kg body weight (b. w.), 15min after the intraperitoneal administration of NA (120mg/kg b. w.). The NA/STZ-induced type 2 diabetic rats were orally treated with navel orange peel hydroethanolic extract, naringin and narengenin at dose level of 100mg/kg b. w./day for 4 weeks. The treatments with navel orange peel hydroethanolic extract, naringin and narengenin potentially alleviated the lowered serum insulin and C-peptide levels, the depleted liver glycogen content, the elevated liver glucose-6-phosphatase and glycogen phosphorylase activities, the deteriorated serum lipid profile, and the suppressed liver antioxidant defense system of NA/STZ-induced type 2 diabetic rats. The treatments also enhanced the mRNA expression of insulin receptor β-subunit, GLUT4 and adiponectin in adipose tissue of STZ/NA-induced type 2 diabetic rats. In conclusion, the navel orange peel hydroethanolic extract, naringin and naringenin have potent anti-diabetic effects in NA/STZ-induced type 2 diabetic rats via their insulinotropic effects and insulin improving action which in turn may be mediated through enhancing insulin receptor, GLUT4 and adiponectin expression in adipose tissue.

Lychee (Litchi chinensis Sonn.) Pulp Phenolic Extract Confers a Protective Activity against Alcoholic Liver Disease in Mice by Alleviating Mitochondrial Dysfunction

Mitochondria play an important role in the initiation and development of alcoholic liver disease (ALD). Our previous studies found lychee pulp phenolic extract (LPPE) exerted protective effect against ALD partly by inhibiting fatty acid β-oxidation, and phenolic-rich lychee pulp extract improved restraint stress-induced liver injury by inhibiting mitochondrial dysfunction. The aim of this study was to investigate whether LPPE exerted protective effect against ALD via modulating mitochondrial function. The mice were treated with an ethanol-containing liquid diet alone or in combination with LPPE for 8 weeks. LPPE supplementation significantly alleviated hepatic steatosis, suppressed serum aspartate aminotransferase activity, and decreased triglyceride levels in serum and liver. On the basis of lipid peroxidation and antioxidant enzyme analyses, LPPE supplementation inhibited serum and hepatic oxidative stress. Moreover, LPPE supplementation significantly suppressed mitochondrial 8-hydroxy-2'-deoxyguanosine level, and increased mitochondrial membrane potential, mitochondrial DNA content, activities of mitochondrial complexes I and IV, and hepatic ATP level. Furthermore, LPPE supplementation significantly inhibited cytoplasmic cytochrome c level and caspase-3 activity, repressed Bax expression and Bax/Bcl-2 ratio, and increased Bcl-2 expression in liver. In summary, LPPE exerts beneficial effects against alcoholic liver injury by alleviating mitochondrial dysfunction.

Protective effect of cirsimaritin against streptozotocin-induced apoptosis in pancreatic beta cells

Objectives

Maintaining glucose homoeostasis is essential for the survival of cells. Despite the various health benefits of Korean thistle (Cirsium japonicum var. maackii), their effects on pancreatic β-cell apoptosis in type 1 diabetes mellitus and the underlying mechanisms remain unclear, and experimentally investigated in this study.

Methods

The effects of C. japonicum var. maackii and its active component cirsimaritin against streptozotocin (STZ)-induced cytotoxicity were assessed in INS-1 cells. By Western blotting analysis, protein expressions related to apoptosis were evaluated. The involvement of apoptosis was also confirmed with image-based cytometric assay and caspase activity tests.

Key findings

Cirsium japonicum var. maackii extract and cirsimaritin in non-toxic concentrations improved cell viability to near normal levels and protected INS-1 cells against STZ-induced damage. In addition, cirsimaritin reduced the intracellular oxidative stress induced by STZ. Cirsimaritin effectively suppressed apoptosis in pancreatic β cells by decreasing the activation of caspase-8 and caspase-3, BID and the DNA repair protein poly (ADP-ribose) polymerase (PARP) and increasing anti-apoptotic BCL-2 protein expression.

Conclusions

This study demonstrates the therapeutic potential and action mechanism of cirsimaritin for the prevention and treatment of type 1 diabetes mellitus.

Efficacy of naringenin against permethrin-induced testicular toxicity in rats

Permethrin (PM), a synthetic pyrethroid insecticide, has broad toxicity spectra. We aimed to investigate the effects of PM on the testes of adult albino rats, examine the recovery response and evaluate the efficacy of naringenin (NG) supplementation. Adult male albino rats were randomly assigned to five groups of six each: control, NG (50 mg/kg), PM (70 mg/kg), recovery (after subsequent withdrawal of PM) and NG-PM group. All treatments were given by oral gavage for 6 weeks and another 3 weeks for the recovery group. At the time of sacrifice, each testis was weighed. Biochemical analysis of epididymal sperm count and serum testosterone level was performed. Testes were processed for histological, ultrastructural and c-Kit immunohistochemical study. PM toxicity was evidenced by a highly significant decrease in testicular weight, epididymal sperm count and serum testosterone level compared to control. Furthermore, testicular structure abnormalities and reduced c-Kit immunoreactions were observed. Stoppage of PM in the recovery group partially reversed PM-induced changes. There was a mild decrease in testicular weight and biochemical parameters compared to control. The structure of seminiferous tubules was partially retained. The NG-PM group showed an overall improvement in testicular weight and biochemical alterations which were confirmed by light and electron microscopic examination. In conclusion, PM induced testicular toxicity, which was ameliorated by NG co-administration. However, stoppage of PM exposure was associated with partial recovery.

Antioxidants: Characterization, natural sources, extraction and analysis

Recently many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However none of them has all the information regarding antioxidants (chemistry, sources, extraction and quantification). This article tries to take a different perspective on antioxidants for the new researcher involved in this field. Antioxidants from fruit, vegetables and beverages play an important role in human health, for example preventing cancer and cardiovascular diseases, and lowering the incidence of different diseases. In this paper the main classes of antioxidants are presented: vitamins, carotenoids and polyphenols. Recently, many analytical methodologies involving diverse instrumental techniques have been developed for the extraction, separation, identification and quantification of these compounds. Antioxidants have been quantified by different researchers using one or more of these methods: in vivo, in vitro, electrochemical, chemiluminescent, electron spin resonance, chromatography, capillary electrophoresis, nuclear magnetic resonance, near infrared spectroscopy and mass spectrometry methods.