Experimental diabetes treated with Achillea santolina: effect on pancreatic oxidative parameters

2,3-Seco and 3-nor guaianolides fromAchillea alpina with antidiabetic activity

In this study, we presented the isolation and characterization of eight novel seco-guaianolide sesquiterpenoids (1-8) and two known guaianolide derivatives (9 and 10), from the aerial part of Achillea alpina L.. Compounds 1-3 were identified as guaianolides bearing an oxygen insertion at the 2, 3 position, while compounds 4-8 belonged to a group of special 3-nor guaianolide sesquiterpenoids. The structural elucidation of 1-8, including their absolute configurations, were accomplished by a combination of spectroscopic data analysis and quantum electronic circular dichroism (ECD) calculations. To evaluate the potential antidiabetic activity of compounds 1-10, we investigated their effects on glucose consumption in palmitic acid (PA)-mediated HepG2-insulin resistance (IR) cells. Among the tested compounds, compound 7 demonstrated the most pronounced ability to reverse IR. Moreover, a mechanistic investigation revealed that compound 7 exerted its antidiabetic effect by reducing the production of the pro-inflammatory cytokine IL-1β, which was achieved through the suppression of the NLRP3 pathway.

Potential Treatment of Dermatophyte Trichophyton rubrum in Rat Model Using Topical Green Biosynthesized Silver Nanoparticles with Achillea santolina Extract

Trichophyton rubrum is the most common dermatophyte, and can cause cutaneous infections in humans and animals (dermatophytosis). In this study, we investigated the anti-dermatophytic potential of green synthesized silver nanoparticles using Achillea santolina extract (AS-AgNPs) in an in vitro and in vivo rat model of dermal T. rubrum dermatophytosis (TRD). The green synthesis of AS-AgNPs was performed using A. santolina extract and characterized by UV-VIS spectroscopy, zeta potential, imaging (transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Energy dispersive X-ray analysis (EDX). The antifungal activity of AS-AgNPs was determined by the broth microdilution method, conidial germination, and hyphal growth inhibition. TEM and SEM were used to study the mode of the antifungal action of AS-AgNPs. AS-AgNPs inhibited the growth of T. rubrum with an MIC of 128 μg/mL, and suppressed the conidial germination and hyphal growth by 55.3% 84.6%, respectively. AS-AgNPs caused modified mycelial structures, increased cell membrane permeability, and cell wall damage. AS-AgNPs significantly increase the permeability of the fungal membrane, as revealed by reducing ergosterol biosynthesis. An increase in the intracellular ROS and the induction of apoptosis were also observed during AS-AgNP treatment. In addition, AS-AgNPs reduced the cell wall integrity, as shown by the reduction in the β-(1,3)-d-glucan synthase and chitin synthase activities. AS-AgNPs showed very low toxicity on primary human dermal fibroblasts (HDF) at the MIC. The topical treatment of the infected skin in the TRD rat model with AS-AgNPs showed a significant reduction in the fugal burden after 7 days and a complete clearance of fungal conidia, with a high recovery of epidermal and dermal structures after 14 days, compared to control rats. Interestingly, AS-AgNPs significantly attenuated the infiltrated inflammatory cells, in association with reducing the tissue proinflammatory cytokines including TNF-α, IL-1, IL-6, MOP and IL-17. In conclusion, our data prove AS-AgNPs to be a novel green topical therapy for dermatophytosis caused by T. rubrum.

Investigation of Anti-Inflammatory Properties, Phytochemical Constituents, Antioxidant, and Antimicrobial Potentials of the Whole Plant Ethanolic Extract of Achillea santolinoides subsp. wilhelmsii (K. Koch) Greuter of Balochistan

Medicinal plants are rich source of phytochemical constitutes and can be used to treat many human diseases. Infectious diseases have always been a major source of concern. Globally, the medicinal plant Achillea wilhelmsii locally known as Bohe Madran is extensively dispersed and widely used as traditional medicine. The aim of this present work is to investigate phytochemical constituents and antimicrobial, antioxidant, and anti-inflammatory properties of the whole plant ethanolic extract of Achillea santolinoides subsp. wilhelmsii (WEEAW) from Balochistan region. The total phenolic content was $14.81\pm 0.18$  mg GAE/g of the extract whereas the total flavonoid content was $12.27\pm 0.12$  mg QE/g of the extract. The antioxidant ability of the extract was analyzed by DPPH (2,2-diphenyl-1-picryl-hydrazyl) scavenging assay and FRAP (ferric reducing antioxidant power) assay in terms of concentration having 50% inhibition (IC50). Results showed that IC50 value for DPPH% inhibition was $0.367\pm 0.82$  mg/mL while FRAP assay represented with IC50 value of $0.485\pm 1.26$  mg/mL. In antileishmanial bioassay, the extract was analyzed against Leishmania major and showed good activity with IC50 value of $7.02\pm 0.83$  mg/mL. Antibacterial assay revealed that Staphylococcus aureus was highly sensitive with the diameter of inhibition zone ( $21.61\pm 1.09$  mm) followed by Salmonella typhi ( $17.32\pm 0.15$  mm), Pseudomonas aeruginosa ( $16.41\pm 0.63$  mm), and Escherichia coli ( $15.30\pm 1.17$  mm) while Klebsiella pneumoniae showed minimum inhibition ( $14.13\pm 0.49$  mm). Antifungal activity was tested against Aspergillus flavus with 89% of inhibition zone and 77% against Mucor mucedo and Aspergillus niger with 74% of inhibition zone. The anti-inflammatory assay was carried out by inhibiting protein denaturation, proteinase inhibitory activity, and heat-induced hemolysis. The IC50 value for protein denaturation was $6.67\pm 1.25$  mg/mL, proteinase inhibitory with IC50 value of $4.12\pm 0.69$  mg/mL, and heat-induced hemolysis assay with IC50 value $4.53\pm 0.82$  mg/mL by comparing to the standard drug aspirin having IC50 value $1.85\pm 0.54$  mg/mL. Results of the current work showed that whole plant ethanolic extract of Achillea wilhelmsii exhibited substantial anti-inflammatory action, thus can be utilized as a traditional treatment. Furthermore, overall finding of this research suggested that the antioxidant potential of the plant aids to prevent free radical damage and reduce the incidence of chronic disease. More research is needed to find out more active compounds present in the extract that are responsible for their pharmacological effects.

Evaluation of Antidiabetic Activity of Oxadiazole Derivative in Rats

The oxadiazole ring has long been used for the treatment of several diseases. This study aimed to analyze the antihyperglycemic and antioxidant roles of the 1,3,4-oxadiazole derivative with its toxicity. Diabetes was induced through intraperitoneal administration of alloxan monohydrate at 150 mg/kg in rats. Glimepiride and acarbose were used as standards. Rats were divided into groups of normal control, disease control, standard, and diabetic rats (treated with 5, 10, and 15 mg/kg of 1,3,4-oxadiazole derivative). After 14 days of oral administration of 1,3,4-oxadiazole derivatives (5, 10, and 15 mg/kg) to the diabetic group, the blood glucose level, body weight, glycated hemoglobin (HbA1c), insulin level, antioxidant effect, and histopathology of the pancreas were performed. The toxicity was measured by estimating liver enzyme, renal function, lipid profile, antioxidative effect, and liver and kidney histopathological study. The blood glucose and body weight were measured before and after treatment. Alloxan significantly increased blood glucose levels, HbA1c, alanine transaminase, aspartate aminotransferase, urea, cholesterol, triglycerides, and creatinine. In contrast, body weight, insulin level, and antioxidant factors were reduced compared to the normal control group. Treatment with oxadiazole derivatives showed a significant reduction in blood glucose levels, HbA1c, alanine transaminase, aspartate aminotransferase, urea, cholesterol, triglycerides, and creatinine as compared to the disease control group. The 1,3,4-oxadiazole derivative significantly improved body weight, insulin level, and antioxidant factors compared to the disease control group. In conclusion, the oxadiazole derivative showed potential antidiabetic activity and indicated its potential as a therapeutic.

Germacranolide- and guaianolide-type sesquiterpenoids from Achillea alpina L. reduce insulin resistance in palmitic acid-treated HepG2 cells via inhibition of the NLRP3 inflammasome pathway

Chemical investigation on the aerial part of Achillea alpina L. led to the isolation of twenty sesquiterpenoids. The structures of the undescribed achigermalides A-H were determined by extensive spectroscopic analysis, including NMR, HRESIMS, UV and IR, and their absolute configurations were established by computational electronic circular dichroism (ECD) method. The X-ray crystal structure for 8α-angeloxy-1β,2β:4β,5β-diepoxy-10β-hydroxy-6βH,7αH,11βH-12,6α-guaianolide was reported for the first time. Glucose consumption was analyzed to investigate the effect of all compounds on palmitic acid (PA)-mediated insulin resistance (IR) in HepG2 cells, and achigermalides D-F, desacetylherbohde A, and 4E,10E-3-(2-methylbutyroyloxy)-germacra-4,10(1)-diene-12,6α-olide appreciably enhanced the glucose consumption at low concentrations of 1.56-6.25 μM. Moreover, achigermalide D decreased the expression of IL-1β and the generation of reactive oxygen species (ROS), and also down-regulated the protein levels of TXNIP, NLRP3, caspase-1 and NF-κB in the Western blot analysis, suggesting achigermalide D mediated IR via the suppression of NLRP3 inflammasome pathway.

Computation Screening of Multi-Target Antidiabetic Properties of Phytochemicals in Common Edible Mediterranean Plants

Diabetes mellitus is a metabolic disease and one of the leading causes of deaths worldwide. Numerous studies support that the Mediterranean diet has preventive and treatment effects on diabetes. These effects have been attributed to the special bioactive composition of Mediterranean foods. The objective of this work was to decipher the antidiabetic activity of Mediterranean edible plant materials using the DIA-DB inverse virtual screening web server. A literature review on the antidiabetic potential of Mediterranean plants was performed and twenty plants were selected for further examination. Subsequently, the most abundant flavonoids, phenolic acids, and terpenes in plant materials were studied to predict their antidiabetic activity. Results showed that flavonoids are the most active phytochemicals as they modulate the function of 17 protein-targets and present high structural similarity with antidiabetic drugs. Their antidiabetic effects are linked with three mechanisms of action, namely (i) regulation of insulin secretion/sensitivity, (ii) regulation of glucose metabolism, and (iii) regulation of lipid metabolism. Overall, the findings can be utilized to understand the antidiabetic activity of edible Mediterranean plants pinpointing the most active phytoconstituents.

Antidiabetic effects of Scrophularia striata ethanolic extract via suppression of Pdx1 and Ins1 expression in pancreatic tissues of diabetic rats

One of the factors that causes severe metabolic imbalance and abnormal changes in many tissues, especially in the pancreas, is the pathological disease of diabetes mellitus. Therefore, in this study, the therapeutic effects of Scrophularia striata were investigated using an animal model in the control of diabetic injury and pancreatic complications caused by diabetes. A total of 66 rats (weight 220–250 g) were randomly divided into: Healthy Control group (rats without diabetes receiving Propylene glycol as solvent); Diabetic control group; 3 experimental healthy groups (receiving the extract with doses of 100, 200 and 400 mg/kg bw/day); 3 treatment groups; and3 pretreatment groups. Diabetes was induced in rats by intraperitoneal STZ (60 mg/kg bw). FBS, HbA1c and insulin were measured after 4 weeks. Pdx1 and Ins1 gene expression was assessed by RT-PCR. The histological evaluation was also performed with H&E staining. The data were analyzed by SPSS ver20 using ANOVA and Tukey tests. By treatment with S. striata ethanolic extract, these factors were close to the normal range. The expression of the Pdx1 and Ins1 genes increased in the treated rats with S. striata extract. Analysis of the obtained data indicates the effect of S. striata in improving the complications of diabetes in rats and can be considered for therapeutic purposes.

Phytochemistry and Evidence-Based Traditional Uses of the Genus Achillea L.: An Update (2011–2021)

Knowledge within the field of phytochemistry research has accelerated at a tremendous speed. The excess of literature reports featuring plants of high ethnopharmacological importance, in combination with our interest in the Asteraceae family and traditional medicine, led us to acknowledge the value of the Achillea L. genus. In a broad context, the various Achillea species are used around the globe for the prevention and treatment of different diseases, including gastrointestinal problems, haemorrhages, pneumonia, rheumatic pains, diuresis, inflammation, infections, and wounds, as well as menstrual and gynaecologic abnormalities. The present review aims to provide and summarize the recent literature (2011–2021) on the phytochemistry of the Achillea genus. In parallel, this study attempts to bridge the reports on the traditional uses with modern pharmacological data. Research articles that focused on secondary metabolites, traditional uses and pharmacological activities were collected from various scientific databases such as Pubmed, ScienceDirect, Reaxys and Google Scholar. This study revealed the presence of 141 phytochemicals, while 24 traditionally used Achillea spp. were discussed in comparison to current data with an experimental basis.

Comprehensive In Silico Screening of the Antiviral Potentialities of a New Humulene Glucoside from Asteriscus hierochunticus against SARS-CoV-2

Chromatographic fractionation of the methanolic extract of Asteriscus hierochunticus whole plant led to the identification of a new humulene glucoside (1). The chemical structure of the isolated compound was elucidated by IR, 1D, 2D NMR, and HRESIMS data analysis to be (-)-(2Z,6E,9E)8α-hydroxy-2,6,9-humulatrien-1(12)-olide. In this study, we report the in silico binding affinities of 1 against four different SARS-CoV-2 proteins (COVID-19 main protease (PDB ID: 6lu7), nonstructural protein (PDB ID: 6W4H), RNA-dependent RNA polymerase (PDB ID: 7BV2), and SARS-CoV-2 helicase (PDB ID: 5RMM)). The isolated compound showed excellent binding affinity values (ΔG) of −21.65, −20.05, −28.93, and −21.73 kcal/mol, respectively, against the target proteins compared to the cocrystallized ligands that exhibited ΔG values of −23.75, −17.65, −23.57, and −15.30 kcal/mol, respectively. Further in silico investigations of the isolated compound (1) for its ADMET and toxicity profiles revealed excellent drug likeliness. On the other hand, the results obtained from in vitro antitrypanosomal, antileishmanial, and antimalarial activities of (1) were not promising.

Protective Effects of Swertiamarin against Methylglyoxal-Induced Epithelial-Mesenchymal Transition by Improving Oxidative Stress in Rat Kidney Epithelial (NRK-52E) Cells

Increased blood glucose in diabetic individuals results in the formation of advanced glycation end products (AGEs), causing various adverse effects on kidney cells, thereby leading to diabetic nephropathy (DN). In this study, the antiglycative potential of Swertiamarin (SM) isolated from the methanolic extract of E. littorale was explored. The effect of SM on protein glycation was studied by incubating bovine serum albumin with fructose at 60 °C in the presence and absence of different concentrations of swertiamarin for 24 h. For comparative analysis, metformin was also used at similar concentrations as SM. Further, to understand the role of SM in preventing DN, in vitro studies using NRK-52E cells were done by treating cells with methylglyoxal (MG) in the presence and absence of SM. SM showed better antiglycative potential as compared to metformin. In addition, SM could prevent the MG mediated pathogenesis in DN by reducing levels of argpyrimidine, oxidative stress and epithelial mesenchymal transition in kidney cells. SM also downregulated the expression of interleukin-6, tumor necrosis factor-α and interleukin-1β. This study, for the first time, reports the antiglycative potential of SM and also provides novel insights into the molecular mechanisms by which SM prevents toxicity of MG on rat kidney cells.

Antinociceptive, anti-inflammatory and antioxidant effects of Boerhavia coccinea extracts and fractions on acute and persistent inflammatory pain models

Background Boerhavia coccinea (Nyctaginaceae) is an herbaceous plant used for the treatment of pain. The aim of this study was to evaluate the antinociceptive and anti-inflammatory activities of the aqueous (AEBC) and ethanol (EEBC) extracts of Boerhavia coccinea as well as the major fractions (F1, F2 and F3) from EEBC. Methods The antinociceptive effect of the extracts and fractions was evaluated using formalin test. AEBC, EEBC and F1 were selected and further evaluated acutely (24 h) and chronically (16 days) in Complete Freund's Adjuvant (CFA)-induced persistent inflammatory pain for their antihyperalgesic and anti-inflammatory effects. They were administered orally (100 and 200 mg/kg/day) from 48 h following the intraplantar injection of 100 µL of CFA. After the 16 days of chronic treatment, rats' spinal cord and brain were collected for the evaluation of oxidative stress parameters namely nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT). Results AEBC, EEBC and F1 significantly inhibited the first and second phases of the formalin-induced pain. They significantly reduced the hyperalgesia both in acute and chronic treatments. These extracts showed no acute anti-inflammatory effect. AEBC and EEBC exhibited anti-inflammatory activities after repeated administration. AEBC, EEBC and F1 significantly reduced MDA level and significantly increased SOD and catalase activities, mainly in the spinal cord. AEBC and EEBC also reduced the NO production in the spinal cord. Conclusions Boerhavia coccinea extracts and F1 possess potent antinociceptive activity which is not related to their anti-inflammatory properties. Their antioxidant effects may contribute to these activities in chronic treatment.

In Vitro Antileishmanial Activity and GC-MS Analysis of Whole Plant Hexane Fraction of Achillea wilhelmsii (WHFAW)

In this study, GC-MS analysis has shown that whole plant hexane fraction of Achillea wilhelmsii (WHFAW) consists of 66 compounds which exhibited antileishmanial activity. Antileishmanial bioassay was the method used for determining antileishmanial activity. The inhibitory concentration (IC50) which was observed for whole plant hexane fraction of Achillea wilhelmsii (WHFAW) against parasitic and vector-borne disease, leishmaniasis, is 58.27 ± 0.52 μg/mL. For leishmanicidal assay, Leishmania major is the species used for analysis. Whole plant methanol extract of Achillea wilhelmsii (WMEAW) and whole plant aqueous fraction of Achillea wilhelmsii (WAFAW) exhibited no antileishmanial activity.

Anil Kumar N, Sharopov F, Ramírez-Alarcón K, Ruiz-Ortega A, Abdulmajid Ayatollahi S, Valere Tsouh Fokou P, Kobarfard F, Amiruddin Zakaria Z, Iriti M, Taheri Y, Martorell M, Sureda A, N. Setzer W, Durazzo A, Lucarini M, Santini A, Capasso R, Adrian Ostrander E, -ur-Rahman A, Iqbal Choudhary M, C. Cho W, Sharifi-Rad J. Antidiabetic Potential of Medicinal Plants and Their Active Components

Diabetes mellitus is one of the major health problems in the world, the incidence and associated mortality are increasing. Inadequate regulation of the blood sugar imposes serious consequences for health. Conventional antidiabetic drugs are effective, however, also with unavoidable side effects. On the other hand, medicinal plants may act as an alternative source of antidiabetic agents. Examples of medicinal plants with antidiabetic potential are described, with focuses on preclinical and clinical studies. The beneficial potential of each plant matrix is given by the combined and concerted action of their profile of biologically active compounds.

Alizarin increase glucose uptake through PI3K/Akt signaling and improve alloxan-induced diabetic mice

Aim: Alizarin (AZ), that can be isolated from Rubia cordifolia, has biological activities such as antioxidation and anti-inflammatory. This study aimed to investigate the effect of AZ on glucose and lipid metabolism disorders in alloxan-induced diabetic mice and also explored the effect of AZ on insulin resistance in 3T3-L1 adipocytes. Results: The research showed that AZ could decrease fasting and postprandial blood glucose, TG, TC and MDA, and it could also increase liver glycogen levels and SOD activity in diabetic mice. AZ could significantly improve the glucose uptake of 3T3-L1 adipocytes under insulin resistance, and could also increase GLUT4 protein expression levels, IRS-1 and Akt protein phosphorylation. Conclusion: These results showed that AZ has the potential to reduce blood sugar and improve insulin resistance.

Beneficial effects of Japanese sake yeast supplement on biochemical, antioxidant, and anti-inflammatory factors in streptozotocin-induced diabetic rats

BACKGROUND

Using chemical agents in the treatment of diabetes mellitus type 2 may have some limitations due to frequent side effects. Some novel and natural agents may be promising alternatives in this case. This study was designed to evaluate the effects of oral Japanese sake yeast supplement, as a novel agent, on biochemical antioxidant and anti-inflammatory parameters in experimentally induced diabetic rats.

MATERIALS AND METHODS

After inducing diabetes (55 mg/kg intraperitoneal injection of streptozotocin), 120 male adult Wistar rats were randomly divided into 5 groups and each group received 0 (control), 15, 30, or 45 mg/kg of sake yeast or was considered a nondiabetic control. Then, the serum levels of tumor necrosis factor-α, IL-6, C-reactive protein, malondialdehyde, glutathione, total antioxidant status, glucose, cholesterol, triglycerides, and insulin were evaluated and compared to baseline measures.

RESULTS

The results showed that oral administration of sake yeast at different concentrations reduced levels of malondialdehyde, glucose, cholesterol, and triglycerides and increased levels of insulin, glutathione, and total antioxidants (P<0.05). The best responses were observed in the nondiabetic control group.

CONCLUSION

Sake yeast supplement may be useful as a novel agent in the treatment of diabetes.

Beneficial effects of Spirogyra Neglecta Extract on antioxidant and anti-inflammatory factors in streptozotocin-induced diabetic rats

Objectives This study was conducted to evaluate the effects of oral supplementation of Spirogyra algae on oxidative damages and inflammatory responses in streptozotocin (STZ)-induced diabetic rats. Methods Diabetes was induced by administration of 55 mg/kg of streptozotocin. A total of sixty-four rats were divided into eight groups of eight rats each as follows:1) non-diabetic control; 2, 3, and 4) non-diabetic rats treated with 15, 30, and 45 mg of Spirogyra algae/kg/d; 5) control diabetic; and 6, 7, and 8) diabetic rats treated with 15, 30, and 45 mg of Spirogyra algae extract. At the end of the trial, the serum concentrations of glucose, interleukin-6 (IL-6), tumor necrosis factor-a (TNF-a), malondialdehyde (MDA), glutathione (GSH), total antioxidant status (TAS), C-reactive protein (CRP), insulin, triglycerides, and cholesterol were examined by specified procedures. Results Our findings indicated that the administration of STZ significantly increased the serum concentrations of glucose, triglycerides, cholesterol, CRP, IL-6, TNF-a, and MDA and decreased the serum levels of GSH and TAS (P<0.05) in diabetic rats. Oral administration of Spirogyra alleviated adverse effects of diabetes on oxidative stress and inflammatory factors in diabetic rats (P<0.05). Conclusion It can be stated that Spirogyra algae extract can be used for treatment of diabetes likely due to prevention of oxidative stress and alleviation of inflammation in the rat model.

Dexpanthenol reduces diabetic nephropathy and renal oxidative stress in rats

Hyperglycemia increases reactive oxygen species (ROS) and the resulting oxidative stress contributes to the development of diabetic complications. Dexpanthenol (Dxp) is the biological active form of pantothenic acid. We investigated whether Dxp administration could decrease oxidative stress as a way to treat renal complications of diabetes mellitus (DM). Thirty-two male Wistar albino rats were divided into four groups: control, Dxp, DM and DM + Dxp. Experimental diabetes was induced by a single dose of streptozotocin (STZ). After administration of STZ, the DM + Dxp group was administered 500 mg/kg Dxp intraperitoneally every day for 6 weeks. At the end of the study, blood glucose levels were measured and rats were sacrificed. Kidneys were embedded in paraffin, sectioned and stained with hematoxylin and eosin, and periodic acid-Schiff. The mean malondialdehyde levels, glutathione peroxidase, superoxide dismutase and catalase activities, and total antioxidant and total oxidant status also were measured. The control group was normal in histological appearance. We observed congestion, inflammation, glomerulosclerosis, tubular desquamation, loss of villi and hydropic degeneration in tubule cells in the DM group. Indicators of oxidative stress were elevated and antioxidant activity was reduced in the DM group compared to controls. In the DM + Dxp group, oxidative stress was decreased, antioxidant activity was increased and histopathological changes were reduced compared to the DM group. We found that Dxp exhibited ameliorative effects on STZ induced diabetic nephropathy by increasing antioxidant activity.

Impact of Non-Enzymatic Glycation in Neurodegenerative Diseases: Role of Natural Products in Prevention

Non-enzymatic protein glycosylation is the addition of free carbonyls to the free amino groups of proteins, amino acids, lipoproteins and nucleic acids resulting in the formation of early glycation products. The early glycation products are also known as Maillard reaction which undergoes dehydration, cyclization and rearrangement to form advanced glycation end-products (AGEs). By and large the researchers in the past have also established that glycation and the AGEs are responsible for most type of metabolic disorders, including diabetes mellitus, cancer, neurological disorders and aging. The amassing of AGEs in the tissues of neurodegenerative diseases shows its involvement in diseases. Therefore, it is likely that inhibition of glycation reaction may extend the lifespan of an individual. The hunt for inhibitors of glycation, mainly using in vitro models, has identified natural compounds able to prevent glycation, especially polyphenols and other natural antioxidants. Extrapolation of results of in vitro studies on the in vivo situation is not straightforward due to differences in the conditions and mechanism of glycation, and bioavailability problems. Nevertheless, existing data allow postulating that enrichment of diet in natural anti-glycating agents may attenuate glycation and, in consequence may halt the aging and neurological problems.

Effects of l-Carnitine on the Follicle-Stimulating Hormone, Luteinizing Hormone, Testosterone, and Testicular Tissue Oxidative Stress Levels in Streptozotocin-Induced Diabetic Rats

The present study was designed to investigate the antioxidant property of l-carnitine (LC) on serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (TH) and testis oxidative stress in streptozotocin (STZ)-induced diabetic rats. The rats were divided into the following groups: group I, control; group II, LC 100 mg/kg/d; group III, diabetic; and groups IV to VI, diabetic rats treated with 50, 100, and 200 mg/kg/d of LC, respectively. Daily injections were given intraperitoneally for 7 weeks. At the end of experimental period, after sacrificing the rats, FSH, LH, TH, total antioxidant capacity (TAC), malondialdehyde (MDA), glutathione (GSH), catalase (CAT), mitochondrial function (MTT), protein carbonyl (PC), and reactive oxygen species (ROS) levels were measured. STZ caused an elevation of MDA, ROS, and PC (P < .001) with reduction of GSH, CAT, TAC, and MTT (P < .001) in the serum levels. Group VI had significantly increased FSH, LH, and TH levels versus the untreated diabetic group (P < .001). Although groups V and VI significantly decreased MDA (P < .001), PC (P < .01), and ROS (P < .01) compared with the untreated diabetic group; only in group VI, the activity of GSH (P < .001), CAT (P < .01), TAC (P < .001), and MTT (P < .001) significantly increased. The results of the present study suggest that LC decreased diabetes-induced oxidative stress complications and also improved serum level of FSH, LH, and TH by reducing levels of lipid peroxidation and increasing antioxidant enzymes.

Variation in Polyphenolic Profiles, Antioxidant and Antimicrobial Activity of Different Achillea Species as Natural Sources of Antiglycative Compounds

A comparative study was carried out on the methanolic extracts from six Achillea species and the examined polyphenols from these plants on the formation of advanced glycation end-products (AGE) in vitro. A. pachycephala which was richer in flavonoids (15 mg quercetin/g W) and phenolics (111.10 mg tannic acid/g DW) with substantial antioxidant activity (IC₅₀  = 365.5 μg/ml) presented strong anti-AGE properties. Chlorogenic acid, luteolin, quercetin and caffeic acid were identified as the major polyphenols in the extracts by HPLC. In general, polyphenolic content follows the order of A. pachycephalla > A. nobilis > A. filipendulina > A. santolina > A. aucheri > A. millefolium. Most extracts exhibited marked anti-AGE ability in the bovine serum albumin (BSA)/methylglyoxal (MG) system, though A. pachycephala showed the highest potential. The formation of AGEs was assessed by monitoring the production of fluorescent products and circular dichroism (CD) spectroscopy. Diminution in free radical production (assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays) is discussed as potential mechanism for delay or reduced AGE. The results demonstrate the antiglycative, antioxidant and antimicrobial potential of Achillea species which can be attributed to polyphenols content and the effectiveness on generation of AGEs, thus Achillea species can be considered as natural sources for slowing down glycation related diseases.

New cytotoxic sesquiterpene lactones from Achillea cretica L. growing in Tunisia

The phytochemical study of Achillea cretica growing in Tunisia led to the isolation of two novel sesquiterpene lactones, which have been designated achicretin 1 and achicretin 2. Their chemical structures were further confirmed by mass spectroscopy (ESI-MS) and by extensive application of one- and two-dimensional NMR spectroscopy. The isolated compounds were tested for their cytotoxic activity against four human cancer cell lines, IGROV-1, OVCAR-3, MCF-7, and HCT-116 using the MTT assay. It has been found that achicretin 2 exhibited more potent inhibitory activity with IC₅₀ = values of 14.0 ± 1.0 and 16.0 ± 2.0 μM against OVCAR-3 and HCT-116 cells, respectively.

Antidiabetic effect of Achillea millefollium through multitarget interactions: α-glucosidases inhibition, insulin sensitization and insulin secretagogue activities

ETHNOPHARMACOLOGICAL IMPORTANCE

Achillea millefolium L. (Asteraceae) is a perennial herb used in Mexican folk medicine for treatment of several pathologies, including inflammatory and spasmodic gastrointestinal disorders, hepatobiliary complaints, overactive cardiovascular, respiratory ailments and diabetes.

AIM OF THE STUDY

To evaluate the potential antidiabetic effect in vivo and to establish the potential mode of action through in vitro approaches of Achillea millefolium.

MATERIALS AND METHODS

The antidiabetic effect of hydroalcoholic extract of Achillea millefolium (HAEAm) was evaluated on the oral glucose tolerance tests, in normoglycemic and experimental Type 2 diabetic mice models. In addition, we evaluated the possible mode of action in in vitro assays to determine α-glucosidases inhibition, the insulin secretion and calcium mobilization in RINm5F cells and PPARγ and GLUT4 expression in 3T3-L1 cells.

RESULTS

HAEAm showed significant glucose diminution on oral glucose tolerance test and in acute experimental Type 2 diabetic assay with respect to the control (p < 0.05). In addition, HAEAm promoted the α-glucosidases inhibition by 55% at 1mg/ml respect to control. On the other hand, HAEAm increased the PPARγ (five-times) and GLUT4 (two-fold) relative expression than control (p < 0.05). Finally, HAEAm significantly increased the insulin secretion and [Ca²⁺]_i compared with control.

CONCLUSION

The HAEAm possesses in vivo antidiabetic effect, having such effect through multitarget modes of action that involve antihyperglycemic (α-glucosidases inhibition), hypoglycemic (insulin secretion) and potential insulin sensitizer (PPARγ/GLUT4 overexpression) actions.

Phytochemical characterization of the Vochysia rufa (Vochysiaceae) extract and its effects on oxidative stress in the pancreata of streptozotocin-induced diabetic rats

Aqueous extract of macerated Vochysia rufa stem bark has been commonly used in the treatment of diabetes. Therefore, we evaluated the antihyperglycemic and antioxidant effects of an extract of V. rufa on the pancreata of streptozotocin (STZ)-induced diabetic rats. Animals received one of the following treatments daily by oral gavage: water (diabetic-control), V. rufa extract (diabetic-V. rufa), or glibenclamide (diabetic-GBD). Total antioxidant capacity; levels of thiobarbituric acid reactive substances, reduced glutathione, and sulfhydryls; and superoxide dismutase, catalase, and glutathione peroxidase (GPx) activities were measured in the pancreas. Biochemical analysis of serum total cholesterol and fractions, triglycerides, creatinine, urea, acid uric, ALP, γ-GT, AST, and ALT was performed, and pancreatic β-cells positive for insulin were evaluated by immunohistochemistry. Rats treated with extract exhibited a decrease in fasting blood glucose compared with levels in diabetic control rats. GPx activity and sulfhydryl levels were significantly lower in diabetic-V. rufa rats compared with those of diabetic-control rats. V. rufa extract acted to normalize the biochemical alterations found in diabetic rats (diabetic-controls), as demonstrated by increases in urea, HDL, ALP, AST, and ALT. Reduction in blood glucose was independent of an increase in insulin. The V. rufa extract was found to be composed of free sugars (inositol, galactose, glucose, mannose, sucrose, arabinose, and ribose) as the main metabolites. Thus, aqueous extract of the stem bark of V. rufa is capable of reducing blood glucose, resulting in an antioxidant effect on the pancreatic tissue of STZ-diabetic rats.

Attenuation of Oxidative Stress and Inflammation by Portulaca oleracea in Streptozotocin-Induced Diabetic Rats

The present study was designed to investigate the protective effect of the aqueous extract of Portulaca oleracea against hyperglycemic, oxidative damage and inflammation in the serum of streptozotocin (STZ)-induced diabetic rats. In the present study, the rats were divided into the following groups of 8 animals each: control, untreated diabetic, 3 Portulaca oleracea (100, 200, 400 mg/kg/d)-treated diabetic groups. At the end of the 4-week period, glucose, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), malondialdehyde (MDA), glutathione (GSH), and total antioxidant status (TAS) levels were measured. STZ caused an elevation in the serum levels of glucose, MDA, IL-6, and TNF-α with reduction in the levels of GSH and TAS ( P < .01). Portulaca oleracea ameliorated glucose, MDA, IL-6, TNF-α, GSH, and TAS levels in diabetic groups versus to the untreated groups ( P < .05). Taken together, Portulaca oleracea prevented hyperglycemia by preventing the oxidative stress and inflammation.

Antihypernociceptive and antioxidant effects of Petersianthus macrocarpus stem bark extracts in rats with complete Freund's adjuvant-induced persistent inflammatory pain

Background Petersianthus macrocarpus (P. Beauv.) Liben (Lecythidaceae) is a plant used in Cameroonian folk medicine to cure ailments such as inflammation and pain. Previous work showed that aqueous (AEPM) and methanol (MEPM) extracts from the stem bark of P. macrocarpus possess acute analgesic activities. The present study evaluates whether the same extracts could inhibit persistent hyperalgesia induced by complete Freund's adjuvant (CFA) in rats. Methods Inflammatory pain was induced by intraplantar injection of CFA into the left hind paw of Wistar rats. AEPM and MEPM were administered either acutely or chronically by the oral route at the doses of 100 and 200 mg/kg/day. The mechanical hyperalgesia was tested using an analgesimeter, while the locomotion activity at the end of experiment was evaluated with an open-field device. Nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) contents were assayed in the brain and spinal cord of rats subjected to 14 days chronic treatment. Results AEPM and MEPM at both doses significantly (p<0.001) inhibited the acute and chronic mechanical hyperalgesia induced by CFA. Although not significant, both extracts increased the mobility of CFA-injected animals. AEPM significantly (p<0.01) reduced the level of nitrate at 100 mg/kg, MDA at 200 mg/kg and significantly (p<0.05) increased the SOD in the spinal cord. MEPM significantly increased the SOD content and reduced the MDA concentration in the brain but had no effect on the nitrate. Conclusions AEPM and MEPM exhibit acute and chronic antihyperalgesic activities. In addition, both extracts possess antioxidant properties that might strengthen their chronic antihyperalgesic effects.

Catechin Treatment Ameliorates Diabetes and Its Complications in Streptozotocin-Induced Diabetic Rats

CONTEXT

Diabetes mellitus causes atherosclerosis and lipid abnormalities. Hypolipidemic and antioxidative properties of catechin (CTN) have been reported in several studies.

OBJECTIVE

This study assesses the possible protective effects of CTN against oxidative damage in the diabetic rats.

MATERIALS AND METHODS

The rats were divided into the control, untreated diabetic, and 3 CTN-treated diabetic groups (20, 40, and 80 mg/kg/d, intraperitoneal). The diabetic rats were induced by streptozotocin. Catechin was injected for 4 weeks. At the end of the experimental period, glucose, lipid profile, apoprotein A-I (apo A-I), apoprotein B (apo B), malondialdehyde (MDA) levels, and antioxidant enzymes including glutathione-S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) activities were determined in serum. Statistical analyses were performed using the InStat 3.0 program.

RESULTS

Streptozotocin caused an elevation of glucose, MDA, triglycerides (TGs), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and apo B with reduction in high-density lipoprotein cholesterol (HDL-C), apo A-I, SOD, CAT, and GST in the serum (P < .05). The findings showed that the significant elevation in the body weight, glucose, MDA, TG, TC, LDL-C, and apo B and reduction in HDL-C, apo A-I, SOD, CAT, and GST were ameliorated in the CTN-treated diabetic groups versus the untreated group, in a dose-dependent manner (P < .05).

CONCLUSION

The present investigation proposes that CTN may ameliorate diabetes and its complications by modification of oxidative stress.

Immunomodulatory and antioxidant effects of saffron aqueous extract (Crocus sativus L.) on streptozotocin-induced diabetes in rats

Introduction

Crocus sativus L. (saffron) has many biological effects such as antioxidant property. The present study investigated the immunomodulatory effects of the aqueous saffron extract on streptozotocin (STZ)-induced diabetic rats.

Materials and methods

In this study, the rats were divided into the following groups of 9 animals each: control, untreated diabetic, three saffron extract-treated diabetic groups. Diabetes was induced by STZ in rats. Saffron was administered 3 days after STZ administration; these injections were continued to the end of the study (4 weeks). At the end of the 4-week period, blood was drawn for biochemical assays and the abdominal aorta was removed for detecting the inflammatory cytokines expression.

Results

We found that saffron decreased blood glucose, malondialdehyde, nitric oxide, total lipids, triglycerides, cholesterol levels significantly (p < 0.01) and increased glutathione level, catalase, and superoxide dismutase activities in the saffron-treated diabetic groups compared with the untreated groups, in a dose dependent manner (p < 0.05, p < 0.01, p < 0.001). On the other hand, saffron-treated diabetic rats inhibited the expression of inflammatory cytokines in the abdominal aorta versus the untreated diabetic rats.

Conclusion

Our results validate the use of saffron as a treatment against diabetes mellitus and its vascular complications.

The Chemical Composition of Achillea wilhelmsii C. Koch and Its Desirable Effects on Hyperglycemia, Inflammatory Mediators and Hypercholesterolemia as Risk Factors for Cardiometabolic Disease

This study was done to identify the content compounds of Achillea wilhelmsii (A. wilhelmsii) and to evaluate its hypoglycemic and anti-hypercholesterolemic activity and effect on inflammatory mediators. The extracts and fractions of A. wilhelmsii were thoroughly analyzed using high performance liquid chromatography (HPLC), and the total content of phenols and flavonoids was determined. The hypoglycemic activity was evaluated in vivo using alloxan-induced diabetic mice. The effect upon inflammatory mediators was evaluated in vitro using the human monocytic leukemia cell line (THP-1). The anti-hypercholesterolemic activity was evaluated in vitro using the 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase assay kit. The water extract (WE)-treated group showed the highest reduction in the fasting blood glucose levels (FBGL). The chloroform fraction (CF) and ethyl acetate fraction (EAF) both showed a significant ability to reduce the secretion of tumor necrosis factor alpha (TNF-α). The EAF, however, also attenuated the levels of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9). The CF showed the most significant 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) inhibition activity. The five main compounds in the CF were isolated and identified. Out of the five compounds in the CF, 1β,10β-epoxydesacetoxymatricarin (CP1) and leucodin (CP2) showed the highest anti-hypercholesterolemic potential. A molecular docking study provided corresponding results.

Diabetes mellitus and its management with medicinal plants: A perspective based on Iranian research

ETHNOPHARMACOLOGICAL RELEVANCE

Complementary and alternative medicine has been increasingly used to treat chronic illnesses, such as diabetes mellitus. However, various limitations in terms of their application and efficacies exist. Furthermore, there is still much to be done to discover the right herbal medicine for diabetes.

AIM OF THE STUDY

This paper aims to evaluate previous herbal studies on the management of diabetes mellitus, to address their strengths and weaknesses and propose a general framework for future studies.

APPROACH AND METHODS

Data sources such as PubMed, ScienceDirect, Scopus, SpringerLink, and Wiley were searched, limited to Iran, using 36 search terms such as herbal, traditional, medicine, and phytopharmacy in combination with diabetes and related complications. Reviewed articles were evaluated regarding the use of botanical nomenclature and included information on (1) identity of plants and plant parts used, (2) the processing procedure, and (3) the extraction process. The main outcomes were extracted and then surveyed in terms of the efficacies of herbs in the management of diabetes mellitus. Then a comparative study was performed between Iranian and non-Iranian studies with respect to herbs best studied in Iran.

RESULTS

Of the 82 herbs studied in Iran, only six herbs were endemic and 19 were studied in detail. Although most of the reviewed herbs were found to decrease the level of blood glucose (BG) and/or glycated hemoglobin (HbA1C) in both Iranian and non-Iranian studies, information on their pharmacological mechanisms is scarce. However, the level of HbA1C was measured in a limited number of clinical trials or animal studies. Available information on both short- and long-term use of studied herbs on diabetes related complications and functions of involved organs as well as comorbid depression and/or simultaneous changes in lifestyle is also insufficient. Furthermore, little or no information on their phytochemical, toxicological, and herb-drug interaction properties is available. It is worth noting that the efficacy of the reviewed herbs has been studied scarcely in both humans and animals regarding both Iranian and non-Iranian studies. A significant number of reviewed articles failed to cite the scientific name of herbs and include information on the processing procedure and the extraction process.

CONCLUSIONS

Treatment of diabetes mellitus as a multifactorial disease using herbal medicines requires a comprehensive approach. In order to discover the right herbal medicine for the management of diabetes many other important factors than the levels of BG, HbA1C and insulin should be considered. According to our criteria, all the reviewed herbs suffered from inadequate investigation in human, animal and in vitro models in this respect, whereas they are worth investigating further. However, more research on endemic plants and the traditional history of herbal medicine is warranted. In our opinion, the pharmacological, toxicological, and phytochemical information should be obtained before clinical trials. Furthermore, information such as botanical scientific nomenclature, side effects, and toxicity will improve the quality and validity of publications in herbal research. In particular, designing a database covering all valid information about herbs and/or diseases will decrease unnecessary costs and increase the efficiency of research.

Chrysin treatment improves diabetes and its complications in liver, brain, and pancreas in streptozotocin-induced diabetic rats

Chrysin (CH) is a natural flavonoid with pharmacological influences. The purpose of the current study was the assessment of possible protective effects of CH against oxidative damage in the serum, liver, brain, and pancreas of streptozotocin (STZ)- induced diabetic rats. In the present study, the rats were divided into the following groups of 8 animals each: control, untreated diabetic, 3 CH (20, 40, 80 mg/kg/day)-treated diabetic groups. To find out the modulations of cellular antioxidant defense systems, malondialdehyde (MDA) level and antioxidant enzymes including glutathione-S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) activities were determined in the serum, liver, brain, and pancreas. STZ caused an elevation of glucose, MDA, TG, TC, LDL-C and with reduction of HDL-C, total protein, SOD, CAT, and GST in the serum, liver, brain, and pancreas (p < 0.01). The findings showed that the significant elevation in the glucose, MDA, TG, TC, LDL-C and reduction of HDL-C, total protein, SOD, CAT, and GST were ameliorated in the CH-treated diabetic groups versus to the untreated groups, in a dose dependent manner (p < 0.05). The current study offers that CH may be recovered diabetes and its complications by modification of oxidative stress.

Antioxidant and α-glucosidase inhibitory activities of Achillea tenorii

CONTEXT

There is a need for the discovery of novel natural remedies to prevent and treat metabolic disorders such as hyperglycemia, type II non-insulin-dependent diabetes mellitus, and obesity. Several Achillea species have been utilized for centuries all around the world and are generally considered effective as hypoglycemic.

OBJECTIVE

Considering the ethnobotanical uses of Achillea genus, we evaluated the in vitro inhibitory activity of Achillea tenorii Grande (Asteraceae) extract on α-glucosidase, which is a valuable target to prevent and treat metabolic disorders. We also tested its antioxidant activity. Moreover, the phytochemical profile was discussed from a chemotaxonomic point of view.

MATERIALS AND METHODS

In vitro α-glucosidase inhibition of crude ethanolic extract obtained from the aerial parts was assayed as well as the in vitro antioxidant activity (ABTS, DPPH, and FRAP-FZ tests) was measured. The extract was characterized from a phytochemical point of view by means of spectroscopic analysis.

RESULTS

The extract results endowed with α-glucosidase inhibitory activity (IC50 32 µg/mL) with a particular mechanism of action definable as un-competitive, which differed from the mechanism observed for the best-known α-glucosidase inhibitor (acarbose and miglitol). In addition, a considerable antioxidant potential has been found for A. tenorii extract, which resulted mainly constituted by phenolic compounds such as caffeoylquinic acids and flavonoids.

DISCUSSION AND CONCLUSIONS

These results suggest the potential of A. tenorii as a possible natural remedy to prevent and treat metabolic disorders of carbohydrates.

Iranian medicinal plants for diabetes mellitus: a systematic review

In the Iranian traditional medicine a significant usage of herbs is promoted for their anti-diabetic activity. The aim of this review to assess the efficacy of glucose lowering effects of medicinal plants cultivated in Iran. An electronic literature search of MEDLINE, Science Direct, EMBASE, Scopus, Web of Science, Cochrane Library Database, Ebsco and Google Scholar from database inception conducted up to May 2012. A total of 85 studies (18 humans and 67 animals) examining 62 plants were reviewed. The quality of Randomized Controlled Trials (RCTs) assessed by using the Jadad scale. Among the RCTs studies, the best results in glycemic control was found in Aloe vera, Citrullus colocynthus, Plantago ovata, Silybum marianum, Rheum ribes and Urtica dioica. The majority of plants that have been studied for antidiabetic activity showed promising results. However, efficacy and safety of the most plants used in the treatment of diabetes are not sufficient.

Ethnopharmacological study of medicinal plants used in the treatment of CNS disorders in Sinai Peninsula, Egypt

ETHNOPHARMACOLOGICAL RELEVANCE

To provide ethnopharmacological information on the use of medicinal plants for central nervous system (CNS) disorders in the Sinai Peninsula region (Egypt). To collect, analyze and evaluate the ethnobotanical knowledge about these medicinal plants in the Sinai Peninsula region with 61,000 km (2) and 379,000 inhabitants.

METHODOLOGY

Field work was concluded between March 2006 and May 2011, using semi-structured questionnaire with 700 informants (mean age: 59; 100% men) from 117 settlements of 17 Bedouin tribes. Transects walks in wild herbal plant collection areas and bibliographical review on the collected plants were also conducted. The Interview/ Inhabitant index (I/P), relative importance value of the species and informant consensus factor (FIC) were calculated.

RESULTS

More than 300 species were traditionally used in folk medicine in the Sinai Peninsula; 101 of these species belonging to 40 families were reported as useful in different CNS disorders. Only 5 species are endemic of the studied area. All different part plants were used, leaves and aerial parts being the most frequent. Most of the remedies were prepared as infusion or decoction, while oral administration was the most common way to be used. Gastrointestinal (67.3%) and respiratory disorders (42.57%) were also reported as frequently treated by Bedouins with herbal remedies.

CONCLUSIONS

Only a few species were found where the traditional use is supported by pharmacological studies (Acacia nilotica, Achillea fragrantissima, Ajuga iva or Mentha longifolia). No bibliographical references in the scientific literature were found for 22 species (21.78%); finally, several studies were published with different pharmacological activities than those provided by Bedouins.

Management of diabetic complications: a chemical constituents based approach

ETHNOPHARMACOLOGICAL RELEVANCE

Long term hyperglycemia leads to development of complications associated with diabetes. Diabetic complications are now a global health problem without effective therapeutic approach. Hyperglycemia and oxidative stress are important components for the development of diabetic complications. Over the past few decades, herbal medicines have attracted much attention as potential therapeutic agents in the prevention and treatment of diabetic complications due to their multiple targets and less toxic side effects. This review aims to assess the current available knowledge of medicinal herbs for attenuation and management of diabetic complications and their underlying mechanisms.

MATERIAL AND METHODS

Bibliographic investigation was carried out by scrutinizing classical text books and peer reviewed papers, consulting worldwide accepted scientific databases (SCOPUS, PUBMED, SCIELO, NISCAIR, Google Scholar) to retrieve available published literature. The inclusion criteria for the selection of plants were based upon all medicinal herbs and their active compounds with attributed potentials in relieving diabetic complications. Moreover, plants which have potential effect in ameliorating oxidative stress in diabetic animals have been included.

RESULTS

Overall, 238 articles were reviewed for plant literature and out of the reviewed literature, 127 articles were selected for the study. Various medicinal plants/plant extracts containing flavonoids, alkaloids, phenolic compounds, terpenoids, saponins and phytosterol type chemical constituents were found to be effective in the management of diabetic complications. This effect might be attributed to amelioration of persistent hyperglycemia, oxidative stress and modulation of various metabolic pathways involved in the pathogenesis of diabetic complications.

CONCLUSION

Screening chemical candidate from herbal medicine might be a promising approach for new drug discovery to treat the diabetic complications. There is still a dire need to explore the mechanism of action of various plant extracts and their toxicity profile and to determine their role in therapy of diabetic complications. Moreover, a perfect rodent model which completely mimics human diabetic complications should be developed.

Toxicological and pharmacological concerns on oxidative stress and related diseases

Although reactive oxygen species (ROS) such as superoxide, hydrogen peroxide and hydroxyl radical are generated as the natural byproduct of normal oxygen metabolism, they can create oxidative damage via interaction with bio-molecules. The role of oxidative stress as a remarkable upstream part is frequently reported in the signaling cascade of inflammation as well as chemo attractant production. Even though hydrogen peroxide can control cell signaling and stimulate cell proliferation at low levels, in higher concentrations it can initiate apoptosis and in very high levels may create necrosis. So far, the role of ROS in cellular damage and death is well documented with implicating in a broad range of degenerative alterations e.g. carcinogenesis, aging and other oxidative stress related diseases (OSRDs). Reversely, it is cleared that antioxidants are potentially able to suppress (at least in part) the immune system and to enhance the normal cellular protective responses to tissue damage. In this review, we aimed to provide insights on diverse OSRDs, which are correlated with the concept of oxidative stress as well as its cellular effects that can be inhibited by antioxidants. Resveratrol, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, statins, nebivolol and carvedilol, pentaerythritol tetranitrate, mitochondria-targeted antioxidants, and plant-derived drugs (alone or combined) are the potential medicines that can be used to control OSRD.

Pharmacological and phytochemical appraisal of selected medicinal plants from jordan with claimed antidiabetic activities

Plant species have long been regarded as possessing the principal ingredients used in widely disseminated ethnomedical practices. Different surveys showed that medicinal plant species used by the inhabitants of Jordan for the traditional treatment of diabetes are inadequately screened for their therapeutic/preventive potential and phytochemical findings. In this review, traditional herbal medicine pursued indigenously with its methods of preparation and its active constituents are listed. Studies of random screening for selective antidiabetic bioactivity and plausible mechanisms of action of local species, domesticated greens, or wild plants are briefly discussed. Recommended future directives incurring the design and conduct of comprehensive trials are pointed out to validate the usefulness of these active plants or bioactive secondary metabolites either alone or in combination with existing conventional therapies.

In Vitro Anti-rotaviral Activity of Achillea kellalensis

Background

Achillea kellalensis, which is frequently used by Chaharmahal va Bakhtiarians residing in, Southwest of Iran, as a traditional herbal medicine for the treatment of acute diarrhea, has been selected to examine its antiviral activities against bovine rotavirus and cell toxicity activity in MA-104 cells.

Objectives

The aim of this study was to evaluate the in vitro cytotoxic and anti-rotavirus properties of crude extracts of A. kellalensis.

Materials and Methods

The dried and powdered flowers of Achillea kellalensis were extracted with hot water and ethanol 50% (v/v). The cell viability and toxicity of the extracts were evaluated on MA-104 cells using four methods; trypan blue dye, NR, crystal violet and MTT assay. The in vitro anti-rotavirus properties were determined via four different assays, in order to evaluate the direct inhibition and/or the inhibition of viral replication.

Results

Cytotoxicity of two A. kellalensis extracts showed different concentrations. Hydro-alcoholic extract had low CC₅₀ at 600 µg/mL by the NR assay while the aqueous extract had high CC₅₀ at 1000µg/mL by the crystal violet method. In the simultaneous treatment assay and post treatment assay, the extracts were able to prevent viral replication and inhibit the viral CPE on MA-104 cells at 10 TCID₅₀, but the extracts did not exhibit direct antiviral activity on rotavirus adsorption. The effective concentration (EC₅₀) of both extracts was observed to be 100 µg/mL.

Conclusions

These results indicate that A. kellalensis extracts exert potent anti-rotaviral activity only after viral adsorption. The two extracts from A. kellalensis showed a good selectivity index. Also these results suggest that extracts prepared from the flowers of A. kellalensis may be potential anti-rotaviral agents in vivo and be useful in veterinary medicine.

Protective effect of polyphenols extract of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) on hypercholesterolemia-induced oxidative stress in rats

The present study examines the effect of polyphenols extract of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) (APE) on high cholesterol diet fed rats (HCD). APE was orally administrated by gavage at doses of 10, 40 and 200 mg total phenolics/kg body weight of rats once a day for 28 days. At the end of four weeks, serum triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C), and markers of oxidative stress viz., malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the serum and liver of HCD and normal rats were assessed and compared. The results showed that administration of APE was significantly effective in decreasing the serum levels of TC, LDL-C and MDA, increasing the serum level of HDL-C and antioxidant capacity. In addition, oral gavage of APE could also increase the antioxidant capacity, CAT and GSH-Px activities in liver. These results suggested that APE exerted a high hypocholesterolemic and antioxidant activities, which might be characterized by a protective effect on cardiovascular health in vivo.

Antidiabetic and vasoprotective activity of lithium: Role of glycogen synthase kinase-3

OBJECTIVES

Lithium is a drug of choice in maniac disorder. Lithium inhibits the glycogen synthase kinase-3 (GSK-3), an enzyme involved in the insulin signalling pathway. Elevated levels of GSK-3 were found in diabetic rats and humans. We aimed to determine the effect of lithium chloride in diabetes and associated vascular complications in diabetic rats.

MATERIALS AND METHODS

Type 2 diabetes was induced by high fat diet and low dose of streptozotocin. Diabetic rats were divided into diabetic control and lithium chloride treatment groups. Lithium chloride was used as a GSK-3 inhibitor. The treatment was given for 4 weeks. Various biochemical parameters were measured before initiation and the end of treatment. Systolic blood pressure was measured by the non-invasive tail-cuff method, while various biochemical and tissue parameters were estimated for efficacy. Vasoreactivity was performed by taking the contractile response of H(2)O(2) (10(-6) M to 10(-3)M) and angiotensin II (10(-11) to 10(-7) M) in rat thoracic aortas of different groups. Statistical comparisons between all groups were performed by using two tailed one-way ANOVA followed by the Dunnett test. P-values <0.05 were considered statistically significant.

RESULTS

Treatment with lithium chloride significantly reduced the augmented systolic blood pressure, various biochemical parameters, and antioxidant parameters in diabetic-treated rats. Treatment also showed the decrease in augmented responses of H(2)O(2) and angiotensin II in rat thoracic aortas of treated rats.

CONCLUSIONS

We can conclude that lithium chloride treatment reduces the diabetic state as well as diabetes-induced vascular dysfunction.

Antidiabetic Activity of Terminalia sericea Constituents

Diabetes mellitus is an endocrine disorder that affects more than 100 million people worldwide. South African plants namely Terminalia sericea, Euclea natalensis, Warbugia salutaris, Aloe ferox, Artemisia afra, Sclerocarya birrea, Spirostachys africana and Psidium guajava were investigated for their in vitro α-glucosidase and α-amylase properties, and antioxidant activities. Terminalia sericea stem bark extract showed the best results against α-glucosidase and α-amylase enzymes. Bioassay-guided fractionation of an acetone extract of T. sericea stem bark led to the isolation of four known compounds namely β-sitosterol (1), β-sitosterol-3-acetate (2), lupeol (3), and stigma-4-ene-3-one (4), in addition to two inseparable sets of mixtures of isomers [epicatechin-catechin (M1), and gallocatechin-epigallocatechin (M2). 1 and 3 showed the best inhibitory activity on α-glucosidase (IC50:54.5 and 66.5 μM). Bio-evaluation of the inhibitory activity of the purified compounds on α-amylase showed that 3 and 1 exhibited IC50 values of 140.7 and 216.02 μM, respectively against α-amylase. Compounds 2, M1, 3 and M2 were found to be nontoxic to Vero cells. This study is the first to report α-glucosidase and α-amylase activity of M1, M2, 2 and 4 isolated from T. sericea, which validated the traditional use of the bark of T. sericea for diabetes in South Africa.