Nitric oxide, a janus-faced therapeutic target for diabetic microangiopathy-Friend or foe?

Comparative evaluation of antioxidant activity, total phenolic content, anti-inflammatory, and antibacterial potential of Euphorbia-derived functional products

This study assessed the medicinal properties of Euphorbia resinifera O. Berg (E. resinifera) and Euphorbia officinarum subsp echinus (Hook.f. and Coss.) Vindt (Euphorbia echinus, known for their pharmaceutical benefits. Extracts from their flowers, stems, propolis, and honey were examined for phenolic content, antioxidant, anti-inflammatory, and antibacterial activities. Total phenolic content (TPC), total flavonoid content (TFC), and total condensed tannin (TCC) were determined using specific methods. Antioxidant potential was assessed through various tests including DPPH, FRAP, ABTS, and Total antioxidant capacity. Anti-inflammatory effects were evaluated using phenol-induced ear edema in rats, while antibacterial activity was measured against Gram-positive (Staphylococcus aureus ATCC 6538) and Gram-negative (E. coli ATCC 10536) bacteria. Among the extracts, the aqueous propolis extract of E. resinifera demonstrated exceptional antioxidant capabilities, with low IC50 values for DPPH (0.07 ± 0.00 mg/mL) and ABTS (0.13 ± 0.00 mg/mL), as well as high TAC (176.72 ± 0.18 mg AA/mg extract) and FRAP (86.45 ± 1.45 mg AA/mg extract) values. Furthermore, the anti-inflammatory effect of E. resinifera propolis extracts surpassed that of indomethacin, yielding edema percentages of 3.92% and 11.33% for the aqueous and ethanolic extracts, respectively. Microbiological results indicated that the aqueous extract of E. resinifera flower exhibited the most potent inhibitory action against S. aureus, with an inhibition zone diameter (IZD) of 21.0 ± 0.00 mm and a minimum inhibitory concentration (MIC) of 3.125 mg/mL. Additionally, only E. resinifera honey displayed the ability to inhibit E. coli growth, with an inhibition zone diameter of 09.30 ± 0.03 mm and a MIC of 0.0433 mg/mL.

Diabetic Nephropathy and Gaseous Modulators

Diabetic nephropathy (DN) remains the leading cause of vascular morbidity and mortality in diabetes patients. Despite the progress in understanding the diabetic disease process and advanced management of nephropathy, a number of patients still progress to end-stage renal disease (ESRD). The underlying mechanism still needs to be clarified. Gaseous signaling molecules, so-called gasotransmitters, such as nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H₂S), have been shown to play an essential role in the development, progression, and ramification of DN depending on their availability and physiological actions. Although the studies on gasotransmitter regulations of DN are still emerging, the evidence revealed an aberrant level of gasotransmitters in patients with diabetes. In studies, different gasotransmitter donors have been implicated in ameliorating diabetic renal dysfunction. In this perspective, we summarized an overview of the recent advances in the physiological relevance of the gaseous molecules and their multifaceted interaction with other potential factors, such as extracellular matrix (ECM), in the severity modulation of DN. Moreover, the perspective of the present review highlights the possible therapeutic interventions of gasotransmitters in ameliorating this dreaded disease.

Inhibition of notch signalling and mesangial expansion by combined glucagon like peptide-1 agonist and crocin therapy in animal model of diabetic nephropathy

Diabetic nephropathy (DN) is one of the devastating complications in diabetes mellitus (DM). Glucagon-like peptide-1 (GLP-1) is one of the incretins secreted from L cells in the intestine. Crocin (a carotenoid component of saffron) has antioxidants properties. We investigated the renal effects of Exendin-4 as a GLP-1 agonist and Crocin in DN.Thirty male rats were divided into five groups: control, type II DM, type II DM + Exendin-4, type II DM + Crocin ‏ and type II DM + Exendine-4 + Crocin. At the end of the experimental period, systolic and diastolic blood pressures were measured, and GFR was calculated. Blood and urine samples were collected for biochemical analysis. Tissue samples were collected from the kidney for histological examination and biochemical measurements of protein expression.Treatment with GLP-1 agonist or Crocin caused a significant improvement in renal function. Better results were achieved with simultaneous administration of both drugs with inhibition of notch signalling pathway and the related proteins.

Acetylcholine Esterase Inhibitory Effect, Antimicrobial, Antioxidant, Metabolomic Profiling, and an In Silico Study of Non-Polar Extract of The Halotolerant Marine Fungus Penicillium chrysogenum MZ945518

Major health issues, such as the rise in oxidative stress, incidences of Alzheimer’s disease, and infections caused by antibiotic-resistant microbes, have prompted researchers to look for new therapeutics. Microbial extracts are still a good source of novel compounds for biotechnological use. The objective of the current work was to investigate marine fungal bioactive compounds with potential antibacterial, antioxidant, and acetylcholinesterase inhibitory effects. Penicillium chrysogenum strain MZ945518 was isolated from the Mediterranean Sea in Egypt. The fungus was halotolerant with a salt tolerance index of 1.3. The mycelial extract showed antifungal properties against Fusarium solani with an inhibitory percentage of 77.5 ± 0.3, followed by Rhizoctonia solani and Fusarium oxysporum with percentages of 52 ± 0.0 and 40 ± 0.5, respectively. The extract also showed antibacterial activity against both Gram-negative and Gram-positive bacterial strains using the agar diffusion technique. The fungal extract was significantly more effective with Proteus mirabilis ATCC 29906 and Micrococcus luteus ATCC 9341; inhibition zones recorded 20 and 12 mm, respectively, compared with the antibiotic gentamycin, which recorded 12 and 10 mm, respectively. The antioxidant activity of the fungus extract revealed that it successfully scavenged DPPH free radicals and recorded an IC50 of 542.5 µg/mL. Additionally, it was capable of reducing Fe3+ to Fe2+ and exhibiting chelating ability in the metal ion-chelating test. The fungal extract was identified as a crucial inhibitor of acetylcholinesterase with an inhibition percentage of 63% and an IC50 value of 60.87 µg/mL. Using gas chromatography–mass spectrometry (GC/MS), 20 metabolites were detected. The most prevalent ones were (Z)-18-octadec-9-enolide and 1,2-Benzenedicarboxylic acid, with ratios of 36.28 and 26.73%, respectively. An in silico study using molecular docking demonstrated interactions between the major metabolites and the target proteins, including: DNA Gyrase, glutathione S-transferase, and Acetylcholinesterase, confirming the extract’s antimicrobial and antioxidant activity. Penicillium chrysogenum MZ945518, a halotolerant strain, has promising bioactive compounds with antibacterial, antioxidant, and acetylcholinesterase inhibitory activities

Comparison of In Vitro Estrogenic Activity of Polygoni multiflori Radix and Cynanchi wilfordii Radix via the Enhancement of ERα/β Expression in MCF7 Cells

Postmenopausal women experience several symptoms, including inflammation and a sharp rise in oxidative stress caused by estrogen deprivation. Although estrogen replacement therapy (ERT) is generally regarded as an effective treatment for menopause, it has been used less frequently due to some adverse effects and high costs. Therefore, there is an immediate need to develop an effective herbal-based treatment that is affordable for low-income populations. Acordingly, this study explored the estrogen-like properties of methanol extracts from Cynanchum wilfordii (CW) and Poligonum multiflorum (PM), two important medicinal plants in Republic of Korea, Japan, and China. Due to the similar names and morphologies of these two radixes, they are frequently confused in the marketplace. Our previous colleagues discriminated between these two plants. In this study, we investigated the estrogenic activity of PM and CW using several in vitro assays with their possible mechanism of action. First, their phytochemical contents, such as gallic acid, 2,3,5,4'-tetrahydroxystilbene-2-O-glucoside (TSG) and emodin, were quantified using high-performance liquid chromatography (HPLC). Secondly, estrogen-like activity was assessed utilizing the well-known E-screen test and gene expression analysis in estrogen receptor (ER)-positive MCF7 cells. ROS inhibition and anti-inflammatory effects were analyzed using HaCaT and Raw 264.7 cells, respectively. Our findings demonstrate that PM extracts significantly increased the expression of the estrogen-dependent genes (ERα, ERβ, pS2) and boosted MCF7 cell proliferation in comparison to CW extracts. Additionally, PM extract demonstrated a significant reduction in reactive oxygen species (ROS) production as well as an enhanced antioxidant profile compared to the CW extract. Further, the PM extract treatment significantly reduced the generation of nitric oxide (NO) in RAW 264.7 cells, a murine macrophage cell line, demonstrating the anti-inflammatory properties of the extract. Finally, this research offers an experimental foundation for the use of PM as a phytoestrogen to minimize menopausal symptoms.

The association between Day-1 urine cadmium excretion and 30-day mortality in patients with acute myocardial infarction: A multi-institutional cohort study

BACKGROUND

The aim of this study was to investigate the relationship between day-1 urine cadmium excretion and 30-day mortality in patients with acute myocardial infarction (AMI) at two centers.

METHODS

A total of 286 patients (222 males and 64 females) with AMI from Huashan Hospital, Shanghai and Chang Gung Memorial Hospital, Taiwan were enrolled. Basic vital signs, history, laboratory results, and day-1 urine excretion of cadmium (D1UECd) were recorded. Disease severity was assessed during the first hospitalization using Killip score, APACHE II score, and SOFA score. The main endpoint was 30-day mortality.

RESULTS

Among the 286 patients, 218 were from Chung Gung Memorial Hospital and 68 were from Huashan Hospital with an average age of 64.2 years. Forty (14%) patients died within 30 days after AMI. The average 24-h urine cadmium level among the Chung Gung Memorial Hospital cohort was 1.5 ± 2.4 μg compared to 1.7 ± 1.7 μg among Huashan Hospital cohort, both higher than the local populations. A higher D1UECd level was significantly associated with a greater risk of 30-day mortality (odds ratio 1.68, 95% confidence interval 1.30-2.16) after controlling for a number of covariates. The ability of D1UECd to discriminate 30-day mortality was excellent, with a very high area under the curve (87.2%, 95% CI 82.0-92.5%).

CONCLUSION

D1UECd was positively correlated and an independent predictor of 30-day mortality in the enrolled AMI patients. D1UECd may be a simple, objective prognostic scoring system in AMI patients.

Redox imbalance in COVID-19 pathophysiology

Background

The pathophysiologic significance of redox imbalance is unquestionable as numerous reports and topic reviews indicate alterations in redox parameters during corona virus disease 2019 (COVID-19). However, a more comprehensive understanding of redox-related parameters in the context of COVID-19-mediated inflammation and pathophysiology is required.

Methods

COVID-19 subjects (n = 64) and control subjects (n = 19) were enrolled, and blood was drawn within 72 h of diagnosis. Serum multiplex assays and peripheral blood mRNA sequencing was performed. Oxidant/free radical (electron paramagnetic resonance (EPR) spectroscopy, nitrite-nitrate assay) and antioxidant (ferrous reducing ability of serum assay and high-performance liquid chromatography) were performed. Multivariate analyses were performed to evaluate potential of indicated parameters to predict clinical outcome.

Results

Significantly greater levels of multiple inflammatory and vascular markers were quantified in the subjects admitted to the ICU compared to non-ICU subjects. Gene set enrichment analyses indicated significant enhancement of oxidant related pathways and biochemical assays confirmed a significant increase in free radical production and uric acid reduction in COVID-19 subjects. Multivariate analyses confirmed a positive association between serum levels of VCAM-1, ICAM-1 and a negative association between the abundance of one electron oxidants (detected by ascorbate radical formation) and mortality in COVID subjects while IL-17c and TSLP levels predicted need for intensive care in COVID-19 subjects.

Conclusion

Herein we demonstrate a significant redox imbalance during COVID-19 infection affirming the potential for manipulation of oxidative stress pathways as a new therapeutic strategy COVID-19. However, further work is requisite for detailed identification of oxidants (O₂^•-, H₂O₂ and/or circulating transition metals such as Fe or Cu) contributing to this imbalance to avoid the repetition of failures using non-specific antioxidant supplementation.

Antioxidant Activity, Total Phenolic and Flavonoid Content and LC–MS Profiling of Leaves Extracts of Alstonia angustiloba

Plants have a wide range of active compounds crucial in treating various diseases. Most people consume plants and herbals as an alternative medicine to improve their health and abilities. A. angustiloba extract showed antinematodal activity against Bursaphelenchus xylophilus, antitrypanosomal action against Trypanosoma brucei and anti-plasmodial activity against the chloroquine-resistant Plasmodium falciparum K1 strain. Moreover, it has demonstrated growth inhibitory properties towards several human cancer cell lines, such as MDA-MB-231, SKOV-3, HeLa, KB cells and A431. DPPH and ABTS assays were carried out to determine the antioxidant activity of the aqueous and 60% methanolic extract of A. angustiloba leaves. Moreover, total phenolic and flavonoid contents were quantified. The presence of potential active compounds was then screened using liquid chromatography coupled with a Q-TOF mass spectrometer (LC–MS) equipped with a dual electrospray ionisation (ESI) source. The EC50 values measured by DPPH for the 60% methanolic and aqueous extracts of A. angustiloba leaves were 80.38 and 94.11 µg/mL, respectively, and for the ABTS assays were 85.80 and 115.43 µg/mL, respectively. The 60% methanolic extract exhibited the highest value of total phenolic and total flavonoid (382.53 ± 15.00 mg GAE/g and 23.45 ± 1.04 mg QE/g), while the aqueous extract had the least value (301.17 ± 3.49 mg GAE/g and 9.73 ± 1.76 mg QE/g). The LC–MS analysis revealed the presence of 103 and 140 compounds in the aqueous and 60% methanolic extract, respectively. It consists of phenolic acids, flavonoids, alkaloids, amino acids, glycosides, alkaloids, etc. It can be concluded that the therapeutic action of this plant is derived from the presence of various active compounds; however, further research is necessary to determine its efficacy in treating diseases.

The Effect of Laminaria japonica on Metabolic Syndrome: A Systematic Review of Its Efficacy and Mechanism of Action

Metabolic syndrome (MetS) is a medical condition characterized by abdominal obesity, insulin resistance, high blood pressure, and hyperlipidemia. An increase in the incidence of MetS provokes an escalation in health care costs and a downturn in quality of life. However, there is currently no cure for MetS, and the absence of immediate treatment for MetS has prompted the development of novel therapies. In accordance with recent studies, the brown seaweed Laminaria japonica (LJP) has anti-inflammatory and antioxidant properties, and so forth. LJP contains bioactive compounds used as food globally, and it has been used as a medicine in East Asian countries. We conducted a systematic review to examine whether LJP could potentially be a useful therapeutic drug for MetS. The following databases were searched from initiation to September 2021: PubMed, Web of Science, EMBASE, and Cochrane Central Register of Controlled Trials Library. Clinical trials and in vivo studies evaluating the effects of LJP on MetS were included. LJP reduces the oxidative stress-related lipid mechanisms, inflammatory cytokines and macrophage-related chemokines, muscle cell proliferation, and migration. Bioactive-glucosidase inhibitors reduce diabetic complications, a therapeutic target in obesity and type 2 diabetes. In obesity, LJP increases AMP-activated protein kinase and decreases acetyl-CoA carboxylase. Based on our findings, we suggest that LJP could treat MetS, as it has pharmacological effects on MetS.

Synthesis and characterization of 2-thiophen flavonoid analogue for free radical scavenging antioxidant analysis

Introduction and Aim: Currently research is focussed on the use of antioxidants in preventing oxidative stress induced diseases. Flavonoids present in plant sources gaining more therapeutic importance due to their antioxidant property, but their solubility and some pharmacokinetic concern, diverted   the current research study towards the synthesis of these flavonoids for their therapeutic potential.  The study was aimed to synthesize and characterize the 2-thiophen flavonoid analogue for free radical scavenging antioxidant activity.   Materials and Methods: The test synthetic compound PNF(3-hydroxy-2-(thiophen-2-yl)-4H-chromen-4-one) a thiophen substituted flavonoid was synthesized from condensation fallowed cyclization reaction in laboratory and DPPH, superoxide, nitric oxide, and hydroxyl radical  scavenging  activity was determined through established in vitro methods.   Results: It suggests that the test flavonoid (PNF) possesses the potent free radical scavenging on DPPH, superoxide, nitric oxide, and hydroxyl radicals with IC50 values of 6.89±25?g/ml,4.04?g/ml, 2.44?g/ml and 2.96?g/ml respectively. The radical scavenging potential of test PNF synthetic compound at different concentrations(10?g-150?g) was compared with that of standard antioxidants such as BHA , ascorbic acid used in the study.   Conclusion: Results from this study indicates that the novel flavonoid PNF exhibited the considerable dose dependant invitro antioxidant activity. These possible activities could be useful to consider the novel synthetic thiophen derived flavonoid as therapeutic antioxidant agent.

Evaluation of different bacterial honey isolates as probiotics and their efficient roles in cholesterol reduction

Continue to hypothesize that honey is a storehouse of beneficial bacteria, and the majority of these isolates are levansucrase producers. Accordingly, ten bacterial strains were isolated from different honey sources. Four honey isolates that had the highest levansucrase production and levan yield were identified by the partial sequencing of the 16S rRNA gene as Achromobacter sp. (10A), Bacillus paralicheniformis (2M), Bacillus subtilis (9A), and Bacillus paranthracis (13M). The cytotoxicity of the selected isolates showed negative blood hemolysis. Also, they are sensitive to the tested antibiotics (Amoxicillin + Flucloxacillin, Ampicillin, Gentamicin, Benzathine benzylpenicillin, Epicephin, Vancomycin, Amikacin, and Zinol). The isolates had strong alkaline stability (pHs 9, 11) and were resistant to severe acidic conditions (29-100 percent). The tested isolates recorded complete tolerance to both H₂O₂ and the bile salt (0.3% Oxgall powder) after 24 h incubation. The cell-free supernatant of the examined strains had antifungal activities against C. Albicans with varying degrees. Also, isolates 2M and 13M showed strong activities against S. aureus. The isolates showed strong adhesion and auto-aggregation capacity. Isolate 10A showed the highest antioxidant activity (91.45%) followed by 2M (47.37%). The isolates recorded different catalase and protease activity. All isolates produced cholesterol oxidase and lipase with different levels. Besides, the four isolates reduced LDL (low-density lipoprotein) to different significant values. The cholesterol-reducing ability varied not only for strains but also for the time of incubation. The previous results recommended these isolates be used safely in solving the LDL problem.

Antiviral Efficacy of Selected Natural Phytochemicals against SARS-CoV-2 Spike Glycoprotein Using Structure-Based Drug Designing

SARS-CoV-2 is a highly virulent coronavirus that first surfaced in late 2019 and has since created a pandemic of the acute respiratory sickness known as “coronavirus disease 2019” (COVID-19), posing a threat to human health and public safety. S-RBD is a coronaviral protein that is essential for a coronavirus (CoV) to bind and penetrate into host cells. As a result, it has become a popular pharmacological target. The goal of this study was to find potential candidates for anti-coronavirus disease 2019 (COVID-19) drugs by targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S-RBD with novel bioactive compounds and molecular interaction studies of 15,000 phytochemicals belonging to different flavonoid subgroups. A spike protein crystal structure attached to the ACE2 structure was obtained from the PDB database. A library of 15,000 phytochemicals was made by collecting compounds from different databases, such as the Zinc-database, PubChem-database, and MPD3-database. This library was docked against a receptor binding domain of a spike glycoprotein through the Molecular Operating Environment (MOE). The top drug candidates Phylloflavan, Milk thistle, Ilexin B and Isosilybin B, after virtual screening, were selected on the basis of the least binding score. Phylloflavan ranked as the top compound because of its least binding affinity score of −14.09 kcal/mol. In silico studies showed that all those compounds showed good activity and could be used as an immunological response with no bioavailability issues. Absorption, distribution, metabolism, excretion and a toxicological analysis were conducted through SwissADME. Stability and effectiveness of the docked complexes were elucidated by performing the 100 ns molecular dynamic simulation through the Desmond package.

The expanding roles of neuronal nitric oxide synthase (NOS1)

The nitric oxide synthases (NOS; EC 1.14.13.39) use L-arginine as a substrate to produce nitric oxide (NO) as a by-product in the tissue microenvironment. NOS1 represents the predominant NO-producing enzyme highly enriched in the brain and known to mediate multiple functions, ranging from learning and memory development to maintaining synaptic plasticity and neuronal development, Alzheimer's disease (AD), psychiatric disorders and behavioral deficits. However, accumulating evidence indicate both canonical and non-canonical roles of NOS1-derived NO in several other tissues and chronic diseases. A better understanding of NOS1-derived NO signaling, and identification and characterization of NO-metabolites in non-neuronal tissues could become useful in diagnosis and prognosis of diseases associated with NOS1 expression. Continued investigation on the roles of NOS1, therefore, will synthesize new knowledge and aid in the discovery of small molecules which could be used to titrate the activities of NOS1-derived NO signaling and NO-metabolites. Here, we address the significance of NOS1 and its byproduct NO in modifying pathophysiological events, which could be beneficial in understanding both the disease mechanisms and therapeutics.

Serum nitrite and nitrate: A potential biomarker for post-covid-19 complications?

Nitric oxide (NO) plays an important role in cardiovascular and immune systems. Quantification of blood nitrite and nitrate, two relatively stable metabolites of NO (generally as NO_x), has been acknowledged, in part, representing NO bioactivity. Dysregulation of NO_x had been reported in SARS-CoV-2 infected populations, but whether patients recovered from COVID-19 disease present with restored NO_x is unknown. In this study, serum NO₂^- and NO₃^- were quantified and analyzed among 109 recovered adults in comparison to a control group of 166 uninfected adults. Nitrite or nitrate levels were not significantly different among mild-, common-, severe- and critical-type patients. However, these recovered patients had dramatically lower NO₂^- and NO₂^-/NO₃^- than the uninfected group (p < 0.0001), with significantly higher NO₃^- levels (p = 0.0023) than the uninfected group. Nitrate and nitrite/nitrate were positively and negatively correlated with patient age, respectively, with age 65 being a turning point among recovered patients. These results indicate that low NO₂^-, low NO₂^-/NO₃^- and high NO₃^- may be potential biomarkers of long-term poor or irreversible outcomes after SARS-CoV-2 infection. It suggests that NO metabolites might serve as a predictor to track the health status of recovered COVID-19 patients, highlighting the need to elucidate the role of NO after SARS-CoV-2 infection.

The exploitation of rice husk biomass for the bio-inspired synthesis of gold nanoparticles as a multifunctional material for various biological and photocatalytic applications

We report an efficient and facile approach to biosynthesis of gold nanoparticles (AuNPs) using the extract of an agro-waste rice husk generated from rice production. The biosynthesized NPs produced were characterized by UV-Visible absorption, TEM, XRD, EDX, and FTIR methods. The impact of temperature and pH on the stability of the synthesized AuNPs was also studied. The TEM imaging revealed the formation of monodispersed spherical NPs with an average size of ~ 15 nm. The absorption spectrum of AuNPs demonstrated the formation of Surface Plasmon Resonance (SPR) peak at 530 nm. The XRD pattern suggested the formation of face-centered cubic (FCC) lattice structure of AuNPs. The FTIR analysis displayed characteristic peaks related to various phytochemicals in the plant extract responsible for reducing and stabilizing NPs. In addition, AuNPs showed thermal stability when subjected to various temperature scales. The AuNPs exhibited an efficiency against the pathogenic bacteria Staphylococcus aureus and pathogenic fungi Candida albicans. The AuNPs 18.5% DPPH free scavenging activity, indicating the antioxidant potential for AuNPs. In addition, the AuNPs showed anticancer activity against the colorectal adenocarcinoma carcinoma cell line. Furthermore, AuNPs displayed significant enhancement in photocatalytic degradation of Methylene Blue and 4-Nitrophenol dyes. The results obtained reveal the possible usage of AuNPs produced using rice husk in several biomedical applications.

Osmoprotectant and antioxidant effects of new synthesized 6-(2-hydroxyethyl)cyclohex-3-enol on barley under drought stress

The aim of present study was synthesize 6-(2-hydroxyethyl)cyclohex-3-enol (11) and investigate its antioxidant properties in barley plants under drought stress. For this aim, 1,4-cyclohexadiene (7) was subjected to [2 + 2] ketene addition reaction with dichloro ketene and the chlorine atoms were reduced. After that, the cyclobutanone ring was converted to a lactone ring and the lactone ring was reduced with LiAlH₄. Subsequently, 6-(2-hydroxyethyl)cyclohex-3-enol (13) was obtained with high yield. The structures of the synthesized molecules were clarified by NMR, FTIR, GCMS spectroscopic methods. Two different methods were used to evaluate antioxidant activity of cyclohexenediol 11. One of them was DPPH radical scavenging activity which was used extensively. Also, osmoprotectant and antioxidant effects of 6-(2-hydroxyethyl)cyclohex-3-enol (13) were investigated in barley under drought stress. Drought decreased the relative water content (RWC) and water potential (WP) in barley leaves. Cyclohexenediol 11 treatment remarkably increased RWC and WP in leaves under drought conditions. Superoxide [Formula: see text] and nitric oxide (NO) accumulated under drought. In cyclohexenediol 11 treated-plants, the accumulation [Formula: see text] and NO were strongly reduced under drought conditions. Our results showed that cyclohexenediol 11 helped barley plants for maintaining water under drought stress; this makes synthetic cyclitol cyclohexenediol 11 as a good osmoprotectant candidate. Another important result in this study was the strong radical scavenging potential of cyclohexenediol 11. We think that much more comprehensive biochemical studies should be conducted to determine how cyclohexenediol 11 performs the radical scavenge role.

Phytochemical and antioxidant activity of Cadaba farinosa Forssk stem bark extracts

Cadaba farinosa is used in traditional medicine for treatment of cancer, diabetes, and rheumatism. The research was aimed at evaluating the phytochemical and antioxidant activity of the extracts. The powdered stem bark was extracted successively with the aid of Soxhlet extractor using n-hexane, ethyl acetate, and methanol. The resulting extracts were concentrated on rotary evaporator and the percentage yields were calculated. The phytochemical and TLC profiles of the extracts were studied. The antioxidant activity of the extracts and ascorbic acid (standard) were determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. The total phenolic content of the extracts and tannic acid (standard) were evaluated using Folin–Ciocalteu reagent. The percentage yields of n-hexane, ethyl acetate, and methanol extracts were found to be 1.19, 1.37, and 13.93%, respectively. The phytochemical screening revealed the presence of tannins, flavonoids, saponins, cardiac glycosides, alkaloids, and triterpenoids. The TLC profiles of the extracts revealed the presence of compounds as evidenced from their R f values. The total phenolic content of ethyl acetate and methanol extracts were found to be 135 and 112 mg, respectively. The free radical scavenging activity demonstrated by the extracts was comparable to ascorbic acid. The ethyl acetate extract had higher phenolic content and demonstrated the highest free radical scavenging with IC50 31.07 mg/mL. The results of research have provided strong preliminary evidence of antioxidant activity which may be because of phenolic compounds in the extracts.

DNA damage in leukocytes and serum nitrite concentration are negatively associated in type 1 diabetes

Chronic hyperglycaemia leads to DNA damage in diabetes and might be associated with nitrosative stress. In this study, we aimed at assessing the level of DNA strand breaks in leukocytes, serum nitrite and nitrate in patients with type 1 diabetes and healthy controls and associations of these parameters with diabetes-related outcomes in a prospective study. The level of DNA damage was determined in 71 patients with type 1 diabetes and 57 healthy controls by comet assay and scored with arbitrary units (AU). The chemiluminescence method was used to measure nitrite and nitrate. Clinical information and data on consumption of alcohol, physical activity and smoking were collected. Progression of complications in patients with diabetes was assessed after a follow-up time of 4-5 years. We observed a higher level of DNA damage in leukocytes of patients with type 1 diabetes compared with healthy subjects [type 1 diabetes AU 50 (36-74.5); control AU 30 (24.1-43), P < 0.001]. According to regression, type 1 diabetes leads to a 2-fold increase in DNA damage. In the group of type 1 diabetes, DNA damage correlated positively with total cholesterol (R = 0.262, P = 0.028) and negatively with serum glucose level (R = -0.284; P = 0.018) and serum nitrite (R = -0.335; P = 0.008). DNA damage was not significantly associated with HbA1c, diabetes duration, complications and lifestyle factors. However, DNA damage > 57 AU was associated with statistically significantly lower serum nitrite and 1.52 higher risk of progression of complications of diabetes over the follow-up period. The latter result was not statistically significant due to insufficient study power [relative risk 1.52 (95% confidence interval = 0.68, 3.42, P = 0.31)]. Our results confirm that type 1 diabetes is associated with a higher level of DNA strand breaks in leukocytes when compared with the reference group and demonstrate the negative association between DNA damage and serum nitrite concentration.

Apolipoprotein E Gene Polymorphism, Glycated Hemoglobin, and Peripheral Arterial Disease Risk in Chinese Type 2 Diabetic Patients

Background

The apolipoprotein E (ApoE) gene polymorphism has been found to influence plasma lipid concentration, and its correlation with peripheral arterial disease (PAD) has been investigated. However, it is unclear whether ApoE is associated with PAD in Chinese type 2 diabetes mellitus (T2DM) patients. Therefore, our study is aimed at investigating the relationship between the ApoE gene polymorphism and PAD in Chinese T2DM patients.

Methods

A total of 192 T2DM patients were divided into two groups: T2DM and T2DM with PAD. The clinical and biochemical parameters were obtained. Polymerase chain reaction was used to identify the genotypes of ApoE. The multivariable logistic regression analysis was used to identify the possible risk factor for PAD.

Results

There were no significant differences in the genotype and allele frequencies of ApoE between the T2DM and T2DM with PAD groups. However, the T2DM with PAD group tended to have more ε4/ε4/

Conclusions

These results demonstrated that there was no evidence of a relationship between ApoE and PAD.

Vitamin D Deficiency May Not Be an Independent Risk Factor for Peripheral Arterial Disease in Middle-Aged and Elderly Patients with Type 2 Diabetes in China

Background

Vitamin D deficiency can lead to the increased severity and prevalence of metabolic disorders. However, the relationship between levels of 25-hydroxyvitamin D (25(OH)D) and peripheral arterial disease (PAD) is controversial. Therefore, the purpose of our study was to explore the relationship between 25(OH)D levels and PAD in middle-aged and elderly type 2 diabetes mellitus (T2DM) patients in China.

Methods

In this study, a total of 183 patients with T2DM were enrolled and categorized into groups with or without PAD. Clinical and biochemical parameters were assessed, and a Pearson analysis was used to identify a possible association between levels of 25(OH)D and glycated hemoglobin (HbA1c). Some biochemical parameters were also assessed in the T2DM patients with PAD according to vitamin D status. Interactions were also explored among HbA1c control, 25(OH)D levels, and PAD. The possible risk factors for PAD were measured by multivariable logistic regression analyses.

Results

Firstly, the parameters including age, HbA1c, and disease duration between T2DM and T2DM+PAD groups showed significantly different. In addition, the frequency of smoking in the group of T2DM patients was significantly less than that in the T2DM patients with the PAD group, while the frequency of well-controlled HbA1c in the patients with T2DM was significantly higher. There is a trend that the levels of 25(OH)D and HbA1c are correlated, but no interactions among vitamin D deficiency, HbA1c control, and PAD were found. However, HbA1c significantly differed between groups with vitamin D deficiency and insufficiency in the T2DM patients with PAD. According to the multivariate logistic regression analyses, the PAD risk factors of T2DM patients were family history of diabetes, smoking, age, disease duration, HbA1c, and LDL.

Conclusions

The findings demonstrate that the deficiency of vitamin D level is not related to PAD, but HbA1c may be linked to the presence of PAD in middle-aged and elderly patients with T2DM in China.

Retinoid X receptor agonists attenuates cardiomyopathy in streptozotocin-induced type 1 diabetes through LKB1-dependent anti-fibrosis effects

Diabetic cardiac fibrosis increases ventricular stiffness and facilitates the occurrence of diastolic dysfunction. Retinoid X receptor (RXR) plays an important role in cardiac development and has been implicated in cardiovascular diseases. In the present study, we investigated the effects of RXR agonist treatment on streptozotocin (STZ)-induced diabetic cardiomyopathy (DCM) and the underlying mechanism. Sprague-Dawley (SD) rats induced by STZ injection were treated with either RXR agonist bexarotene (Bex) or vehicle alone. Echocardiography was performed to determine cardiac structure and function. Cardiac fibroblasts (CFs) were treated with high glucose (HG) with or without the indicated concentration of Bex or the RXR ligand 9-cis-retinoic acid (9-cis-RA). The protein abundance levels were measured along with collagen, body weight (BW), blood biochemical indexes and transforming growth factor-β (TGF-β) levels. The effects of RXRα down-regulation by RXRα small interfering RNA (siRNA) were examined. The results showed that bexarotene treatment resulted in amelioration of left ventricular dysfunction by inhibiting cardiomyocyte apoptosis and myocardial fibrosis. Immunoblot with heart tissue homogenates from diabetic rats revealed that bexarotene activated liver kinase B1 (LKB1) signaling and inhibited p70 ribosomal protein S6 kinase (p70S6K). The increased collagen levels in the heart tissues of DCM rats were reduced by bexarotene treatment. Treatment of CFs with HG resulted in significantly reduced LKB1 activity and increased p70S6K activity. RXRα mediated the antagonism of 9-cis-RA on HG-induced LKB1/p70S6K activation changes in vitro. Our findings suggest that RXR agonist ameliorates STZ-induced DCM by inhibiting myocardial fibrosis via modulation of the LKB1/p70S6K signaling pathway. RXR agonists may serve as novel therapeutic agents for the treatment of DCM.

Total Phenolic, Flavonoid Contents, and Antioxidant Activities of Fruit, Seed, and Bark Extracts of Zanthoxylum armatum DC

Natural antioxidants present in several medicinal plants are responsible for inhibiting the harmful effects of oxidative stress. These plants contain polyphenols and flavonoids that act as free radical scavengers and reduce oxidative stress and may be an alternative remedy to cure various harmful human diseases. This study aims to quantify the total phenolic and flavonoid contents (TPC and TFC) and antioxidant properties of methanol extracts of fruits, seeds, and bark of an important medicinal and aromatic plant, Zanthoxylum armatum collected from wild and cultivated populations in Nepal. TPC was determined by Folin–Ciocalteu colorimetric method using gallic acid as standard, and various concentrations of the extract solutions were measured at 760 nm. TFC was calculated by aluminum chloride colorimetric assay. Quercetin was used as standard, and the absorbance was measured at 510 nm. The antioxidant potential of the different extracts was estimated by DPPH free radical scavenging assay, and the absorbance was measured at 517 nm. The highest TPC value was 226.3 ± 1.14 mg GAE/g in wild fruits, and the lowest was 137.72 ± 4.21 mg GAE/g in cultivated seeds. Similarly, the highest TFC value was 135.17 ± 2.02 mg QE/g in cultivated fruits, and the lowest was 76.58 ± 4.18 mg QE/g in cultivated seeds. The extracts showed variable antioxidant properties. The fruits exhibited excellent antioxidant properties with IC₅₀ values of 40.62 μg/mL and 45.62 μg/mL for cultivated and wild fruits, respectively. Similarly, the IC₅₀ values of the bark were 63.39 μg/mL and 67.82 μg/mL, respectively, for cultivated and wild samples. And the least antioxidant capacity was shown by the seeds extract with IC₅₀ values of 86.75 μg/mL and 94.49 μg/mL for wild and cultivated seeds, respectively. The IC₅₀ value of the standard ascorbic acid was 36.22 μg/mL. Different extracts of Z. armatum contain considerable amount of phenols and flavonoids, including antioxidant properties, suggesting the potential use of this species in pharmacy and phytotherapy as a source of natural antioxidants.

Nitric oxide metabolism is impaired by type 1 diabetes and diabetic nephropathy

Diabetes leads to reduced nitric oxide bioavailability, resulting in endothelial dysfunction. However, overproduction of nitric oxide due to hyperglycaemia is associated with oxidative stress and tissue damage. The objective of this study was to characterise nitric oxide production (NO) and added nitrite and nitrate (NO₂ ^-+NO₃ ^-) concentration in the blood and urine of patients with and without diabetic nephropathy. A total of 268 patients with type 1 diabetes and 69 healthy subjects were included. Diabetic nephropathy was defined as macroalbuminuria and/or estimated glomerular filtration rate below 60 ml/min/1.73 cm². NO₂ ^-+NO₃ ^- concentration was measured by Griess reaction. Production of NO was detected by electron paramagnetic resonance spectroscopy. Blood NO was demonstrated to be higher (P<0.001) and serum NO₂ ^-+NO₃ ^- was lower (P=0.003) in patients with type 1 diabetes and no nephropathy vs. healthy subjects. However, serum NO₂ ^-+NO₃ ^- concentration in patients with diabetes and nephropathy did not differ from the levels observed in healthy controls. Urine excretion of NO₂ ^-+NO₃ ^- was significantly decreased in patients with nephropathy, compared with patients without diabetic kidney disease (P=0.006) and healthy subjects (P=0.010). A significant positive correlation was observed between urine NO₂ ^-+NO₃ ^- and estimated glomerular filtration rate in patients with type 1 diabetes (P=0.002) and healthy subjects (P=0.008). Estimated glomerular filtration rate, albuminuria and diabetic nephropathy status were significant predictors of the whole blood NO and NO₂ ^-+NO₃ ^- in serum and urine in patients with type 1 diabetes, as identified by linear regression models. The present study concludes that NO metabolism is impaired by type 1 diabetes and diabetic nephropathy.

Chemical constituents, antioxidant and cytotoxicity properties of Leonotis leonurus used in the folklore management of neurological disorders in the Eastern Cape, South Africa

In the present study, we evaluated the phytochemical compounds and antioxidant properties of chloroform, ethanol and acetone extracts for leaves and flowers of Leonutus leonurus (L. leonurus) alongside with their cytotoxic effects on human cervical carcinoma (HeLa) cell lines. The phytochemical compounds present in the leaves and flowers of L. leonurus included; phenolics, flavonoids and alkaloids. Their radicals scavenging effects against 2, 2-diphenyl-1-picrylhydrazyl [DPPH] 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonate) [ABTS·+], hydrogen peroxide, nitric oxide as well as metal chelating activities showed dose-dependent activities. Gas chromatography-mass spectrometry (GCMS) analyses revealed the presence of important bioactive compounds, which are associated with antioxidant; and the extracts exhibited toxicity effect against HeLa cells. The findings from this study divulge extracts of L. leonurus as prospective sources of antioxidant and anticancer agents; and hence, further study on their neuroprotective potentials becomes imperative.

Mycochemical Screening and Analysis, Antioxidant Activity, and Biochemical Composition of Fermentation Strain Snef1216 (Penicillium chrysogenum)

Antioxidants are the radical scavengers that inhibit peroxidation and other free-radical processes, which in return safeguard different organisms from various diseases attributed to radical reactions. Synthetic antioxidants inhibit free radicals, but they also have harmful side effects. However, mycochemicals of natural fungal origin are safe and best substitutes for harmful synthetic chemical antioxidants. The prime objectives of the study include appropriate qualitative and quantitative mycochemical screening, antioxidant potential, and chemical composition of Snef1216 (Penicillium chrysogenum). The study has used aluminium chloride colourimetric method, Folin-Ciocalteu reagent assay, and DPPH (1,1-diphenyl-1-picrylhydrazyl) for analysis of total flavonoid content and phenol content and antioxidant activity, respectively. However, the presence of biologically active compounds was screened through gas chromatography-mass spectrometry (GC-MS). Quantitative analysis demonstrated the existence of flavonoids, glycosides, flavones, saponins, phenols, and catecholic tannins excluding alkaloids, terpenoids, steroids, and gallic tannins. The outcomes exposed total flavonoid content and phenolic content in P. chrysogenum were 85.31 ± 1.23 mg·QE/g and 135.77 ± 1.14 mg·GAE/g, respectively. Snef1216 (P. chrysogenum) displayed the highest free-radical scavenging activity with 63.86% inhibition of DPPH. The analysis confirms that Snef1216 (P. chrysogenum) is an alternative source of natural antioxidants. The obtained data have provided the foundation for its use in agricultural, environmental, and pharmaceutical industries.

Phytochemical Analysis, Biochemical and Mineral Composition and GC-MS Profiling of Methanolic Extract of Chinese Arrowhead Sagittaria trifolia L. from Northeast China

Sagittaria trifolia is a medicinal foodstuff of China and East Asia belonging to the family Alismataceae. Samples of S. trifolia tubers were collected from Meihekow, Siping, Jilin, Harbin and Wuchang from Northeast China. The current study was aimed to evaluate the qualitative and quantitative analysis, antioxidant activity, biochemical analysis and chemical composition of different populations of S. trifolia. By using Folin–Ciocalteu, aluminium chloride colourimetric and 1,1-diphenyl-1-picrylhydrazyl (DPPH), total phenol and flavonoids content and antioxidant activity was analysed. Furthermore, chemical composition, biochemical analysis and mineral substances were also determined. The results showed the presence of flavonoids, phenols, saponins, tannins, glycosides and steroids except for alkaloids and terpenoids by qualitative analysis. Quantitative analysis revealed that highest total phenol, flavonoids content and antioxidant potential identified from Meihekow, i.e., 2.307 mg GAE/g, 12.263 mg QE/g and 77.373%, respectively. Gas chromatography-mass spectrometry results showed the presence of 40 chemical compounds corresponding to 99.44% of total extract that might be responsible for antioxidant properties. Mineral and biochemical analysis revealed the presence of calcium, magnesium, potassium, sodium, iron, copper, zinc and, carbohydrate, protein, fibre and fat contents, respectively. Interestingly, all S. trifolia populations collected from different locations possess similar composition. The dietary values, phytoconstituents, antioxidant activities and nutritional and curative chemical compounds of S. trifolia are beneficial for the nutritherapy of human beings.

Comparative study of some bioactive compounds and their antioxidant activity of some berry types

Berries are wealthy in bioactive compounds like phenolic compounds and flavonoids that are deemed antioxidants and are great important to health. This research was performed to examine, recognize and compare bioactive compounds in certain types of berries and their antioxidant activity. The data show that blue berry, black berry and Egyptian black mulberry contain the highest content of most bioactive compounds such as phenolic compounds, flavonoids and tannins, while long mulberry and red currant berry have the lowest content for most of these compounds. They therefore, contain the highest value of antioxidant activity. The chemical composition of the berries varies depending on cultivar, variety, location of growth, environmental conditions and harvest time, as well as post-harvest treatments therefore the composition differed from berry fruit to another. Thus, berry fruits are very useful in nutrition to protect the body from many diseases because of its containment of these compounds, which act as free radicals scavenger that harm the body and thus rid the body of many harmful toxins.

A reliable fluorimetric method to screen the nitric oxide synthase inhibitors in 96 well plate

In general, 4 amino-5-methylamino-2',7'-difluorescein diacetate (DAF-FM-DA) dye is used to detect nitric oxide in biological systems through cell imaging. In this study, we have used 96 well plate format to quantify nitric oxide using DAF-FM-DA through a multimode reader (or independently using fluorospectrometer) and could be visualized in a fluorescence microscope. Similar study otherwise will require a high-end instrument. The method has been validated to screen NOS inhibitors in the HEK 293T cell lines over-expressing the NOS isoforms. We observed that the method is very simple to use, adaptive, sensitive and most importantly it saves time. REAGENTS/TOOLS: Ethanol (70% [v/v] in distilled water), Nω-Nitro-l-arginine (l-NAME), 7-Nitro-Indazole (7-NI) (Sigma, St. Louis, MO), HEK 293T cell lines (National Centre for Cell Science (NCCS), Pune, India), DMEM (Himedia laboratories Pvt), Fetal Bovine Serum (FBS) (Invitrogen, Carlsbad, CA), 100 U/mL penicillin, and 0.1 mg/mL streptomycin in a 5% CO2 atmosphere. Hank's Balanced Salt Solution (HBSS) without Phenol Red of pH 7.4 was prepared with the following composition: NaCl, 8.0g, KCl, 0.4g, CaCl₂, 0.14g, MgSO₄⋅7H₂O, 0.1g, MgCl₂·6H₂O, 0.1g, Na₂HPO₄·2H₂O, 0.06g, KH₂PO₄, 0.06g, glucose, 1.0g, NaHCO₃, 0.35g, H₂O, to 1000 ml, Sterilized and refrigerated, Calcium Ionophore A23187 (Sigma Aldrich 52665-69-7) DAF-FM Di Acetate (Molecular Probes Life Technologies), and DAF-FM Di Aceatate was prepared as a stock solution (5 mM) in DMSO, divided into aliquots and stored at -20 °C, followed by dilution to the required concentration in HBSS buffer before use. EQUIPMENT: Neubauer chamber, Microtube centrifuges (1.5 mL), Micropipettors,10,100, and 1000 mL with corresponding tips, multimode reader (Tecan, Synergy-HT), inverted fluorescence microscope (Nikon, eclipse Ti-S), black flat bottom Microplates (96-well) (Corning 3603).

Serum Levels of Protein-Bound Methylglyoxal-Derived Hydroimidazolone-1 are Independently Correlated with Asymmetric Dimethylarginine

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase, being involved in endothelial dysfunction. Furthermore, ADMA levels have been shown to predict future cardiovascular events in patients with coronary risk factors, such as diabetes and hypertension. We have previously found that glyceraldehyde-derived advanced glycation end products (glycer-AGEs) stimulate ADMA generation in vitro and the levels are associated with ADMA, endothelial dysfunction, and vascular inflammation in humans. However, it remains unclear what structurally distinct glycer-AGEs are independent correlates of ADMA. In this study, we addressed the issue. We measured serum levels of protein-bound and free methylglyoxal-derived hydroimidazolone-1 (MG-H1) and argpyrimidine, two major structurally identified glycer-AGEs by liquid chromatography-tandem mass spectrometry in 128 outpatients, and examined the correlations of these AGEs, vascular stiffness, and inflammation with ADMA. Moreover, we examined whether the changes in serum MG-H1 and argpyrimidine levels after 4-month treatment with oral hypoglycemic agents (OHAs) were associated with those of ADMA in other 44 patients with impaired glucose tolerance or type 2 diabetes. Multiple stepwise regression analysis revealed that protein-bound MG-H1, high-density lipoprotein cholesterol (inversely), high-sensitivity C-reactive protein, and cardio-ankle vascular index were independently correlated with ADMA (R² = 0.259). Treatment with OHAs significantly decreased ADMA levels in 44 glucose-intolerant or type 2 diabetic patients, and the changes in protein-bound MG-H1 levels were positively associated with those in ADMA values (p < 0.05). This study demonstrates that serum levels of protein-bound MG-H1 are independently correlated with ADMA and may be a therapeutic target for cardiovascular disease.

Antidiabetic, antioxidant, molecular docking and HPTLC analysis of miquelianin isolated from Euphorbia schimperi C. Presl

The present study demonstrates the miquelianin or quercetin 3-O-glucuronide (compound 1) isolated from aerial parts of Euphorbia schimperi exhibited significant results for antioxidant and antidiabetic potential. The compound 1 along with kaempferol 3-O-glucuronide (compound 2) and quercetin 3-O-rhamnoside (compound 3) isolated from the same source were quantified by validated HPTLC method. Antioxidant activity was determined by chemical means in terms of ABTS radical cation and DPPH radical scavenging activity. Compound 1 showed significant scavenging activity in both ABTS and DPPH assays as compared to standard BHA. In ABTS method IC₅₀ values of compound 1 and standard BHA is found to be 58.90 ± 3.40 µg/mL and 28.70 ± 5.20 µg/mL respectively while in DPPH assay IC₅₀ values of Compound 1 and standard BHA is 47.20 ± 4.90 µg/mL and 34.50 ± 6.20 µg/mL respectively. Antidiabetic effect was studied through α-amylase and α-glucosidase inhibitory activity. The mechanistic approach through molecular modelling also support the strong binding sites of compound 1 which showed significant α-amylase and α-glucosidase inhibitory activities with IC₅₀ values 128.34 ± 12.30 and 89.20 ± 9.20 µg/mL respectively as compared to acarbose 64.20 ± 5.60 and 52.40 ± 4.60 µg/mL respectively. The results of validated RP-HPTLC analyses revealed the concentration of compound 1 found to be 16.39 µg/mg and for compound 2 and compound 3 as 3.92 and 14.98 µg/mg of dried extract, respectively.

Role of Hyperglycemia-Induced Advanced Glycation End Product (AGE) Accumulation in Atherosclerosis

There is a growing body of evidence that cumulative hyperglycemic exposure plays a central role in the development and progression of atherosclerotic cardiovascular disease in diabetic patients. Monosaccharides, such as glucose, fructose, and glyceraldehyde can react non-enzymatically with amino groups of proteins, lipids, nucleic acids to form senescent macromolecules termed advanced glycation end products (AGEs), whose formation and accumulation has been known to progress in diabetic patients, especially in those with a long history of disease. The sustained accumulation of AGEs could contribute to the phenomenon of metabolic memory or legacy effects observed in long-term follow-up clinical studies of diabetic patients. AGE modification alters the structural integrity and function of various types of macromolecules, and interaction of AGEs with a receptor for AGEs (RAGE) has been shown to evoke inflammatory and thrombotic reactions. Therefore, the AGE–RAGE axis is a novel therapeutic target of atherosclerotic cardiovascular disease in diabetic patients. In this paper, we briefly review the pathological role of AGEs and their receptor RAGE system in atherosclerotic cardiovascular disease, including peripheral artery disease and discuss the clinical utility of measuring AGEs in evaluating the severity of atherosclerosis in patients with diabetes.

Phytochemical Screening for Various Secondary Metabolites, Antioxidant, and Anthelmintic Activity of Coscinium fenestratum Fruit Pulp: A New Biosource for Novel Drug Discovery

Objectives

Coscinium fenestratum (Gaertn.) Colebr. (CF, Family: Menispermaceae) is an important endangered woody climber in India. CF contains various major secondary metabolites for the treatment of various disease conditions. The present study aimed to establish the antioxidant and anthelmintic activity of Coscinium fenestratum fruit pulp.

Materials and Methods

The dried fruit pulp was subjected to aqueous, methanol, and mixed aqueous and methanol (1:1) solvent extraction followed by phytochemical investigations, estimations of alkaloids, phenolics, flavonoids, antioxidant potentiality (DPPH and hydrogen peroxide scavenging methods), and anthelmintic activity tests were carried out.

Results

Preliminary phytochemical screening of CF fruit extracts revealed the presence of alkaloids phenols, flavonoids, tannins, steroids, and resins, which are responsible for biologic properties. The combined aqueous and methanol extract resulted in significant anthelmintic and antioxidant properties in a dose-dependent manner. The DPPH free radical scavenging assay and H₂O₂ assay exhibited IC₅₀ values of 42.38±0.012 µg/mL and 46.80±0.011 µg/mL, respectively. Thereafter, the anthelmintic activity test was carried out against Pheretima posthuma and Taenia solium with the extract at varying concentrations of 25, 50, 100 and 150 mg/mL and compared with standard albendazole (25 and 50 mg/mL) and saline (0.9%) as a control. All the extracts exhibited concentration-dependent paralytic effect, followed by death on the test organism, but significant activity was observed with the combined methanol and aqueous extract.

Conclusion

The study was conducted in order to find possible isolated compounds as a biosources for future novel antioxidants in food and pharmaceutical formulations. Our findings indicate for the first time that the CF fruit pulp has therapeutic values with prominent antioxidant and anthelmintic properties.

The effects of resveratrol and exercise on age and gender-dependent alterations of vascular functions and biomarkers

The purpose of this study was to determine the effects of resveratrol and regular aerobic exercise on vascular functions and biomarkers related to vessel responsiveness in an age and gender-dependent manner. The study used young (3 months) and old (12 months) male and female Wistar albino rats. Resveratrol was given in the drinking water (0.05 mg/ml; approximately 7.5 mg/kg) for 6 weeks. In the exercise group, all rats performed treadmill running at 20 m/min on a 0° incline, 40 min/day, 3 times a week, for 6 weeks. Acetylcholine-induced, endothelium-dependent and sodium nitroprusside-mediated, endothelium-independent relaxations of rat thoracic aorta and blood levels of biomarkers were separately changed by resveratrol intake and exercise-training in an age and gender-dependent manner. Antioxidant enzymes and eNOS expressions in vessels were elevated by resveratrol and exercise. Resveratrol and exercise enhanced gene expressions of non-selective PDE1, 2, 3 and cAMP selective PDE4 but not cGMP selective PDE5 in the aorta. In addition, the aortic mRNA expression of inflammation markers were altered by resveratrol and exercise-training. The results of the study demonstrated that vessel responsiveness and biomarkers related to vascular functions were altered by resveratrol consumption and exercise-training in an age and gender-dependent manner.

IRAP inhibition using HFI419 prevents moderate to severe acetylcholine mediated vasoconstriction in a rabbit model

Coronary artery vasospasm (constriction) caused by reduced nitric oxide bioavailability leads to myocardial infarction. Reduced endothelial release of nitric oxide by the neurotransmitter acetylcholine, leads to paradoxical vasoconstriction as it binds to smooth muscle cell M3 receptors. Thus, inhibition of coronary artery vasospasm will improve clinical outcomes. Inhibition of insulin regulated aminopeptidase has been shown to improve vessel function, thus we tested the hypothesis that HFI419, an inhibitor of insulin regulated aminopeptidase, could reduce blood vessel constriction to acetylcholine. The abdominal aorta was excised from New Zealand white rabbits (n=15) and incubated with 3mM Hcy to induce vascular dysfunction in vitro for 1h. HFI419 was added 5min prior to assessment of vascular function by cumulative doses of acetylcholine. In some rings, vasoconstriction to acetylcholine was observed in aortic rings after pre-incubation with 3mM homocysteine. Incubation with HFI419 inhibited the vasoconstrictive response to acetylcholine, thus improving, but not normalizing, vascular function (11.5±8.9% relaxation vs 79.2±37% constriction, p<0.05). Similarly, in another group with mild vasoconstriction, HFI419 inhibited this effect (34.9±4.6% relaxation vs 11.1±5.2%, constriction, p<0.05). HFI419 had no effect on control aorta or aorta with mild aortic dysfunction. The present study shows that HFI419 prevents acetylcholine mediated vasoconstriction in dysfunctional blood vessels. HFI419 had no effect on normal vasodilation. Our results indicate a therapeutic potential of HFI419 in reducing coronary artery vasospasm.

ADMA: a specific biomarker for pathologic progress in diabetic microvascular complications?

BACKGROUND

This study highlights the role of glycated hemoglobin (HbA1c), asymmetric demethylargine (ADMA) and N-ϵ-(carboxymethyl)-lysine (CML) in different periods of progress in Type 2 diabetes, and identifies a pathomechanism-based biomarker that is linked not only to the metabolic progresses but also to the underlying angiopathic progresses.

METHODS

Peripheral blood samples from 100 healthy volunteers, 227 subjects with prediabetes, 173 subjects with Type 2 diabetes and 92 subjects with early diabetic microvascular complications were collected and analyzed for HbA1c, ADMA and CML.

RESULTS

Compared to HbA1c and CML, ADMA is the strongest independent predictor and a significantly discriminative receiver operating characteristics profile, clearly distinguishing those with early diabetic microvascular complications.

CONCLUSIONS

ADMA maybe serve as a pathomechanism-based biomarker, predicting the progression of microvascular complications.

Vascular endothelium - Gatekeeper of vessel health

The vascular endothelium is an interface between the blood stream and the vessel wall. Changes in this single cell layer of the artery wall are believed of primary importance in the pathogenesis of vascular disease/atherosclerosis. The endothelium responds to humoral, neural and especially hemodynamic stimuli and regulates platelet function, inflammatory responses, vascular smooth muscle cell growth and migration, in addition to modulating vascular tone by synthesizing and releasing vasoactive substances. Compromised endothelial function contributes to the pathogenesis of cardiovascular disease; endothelial 'dysfunction' is associated with risk factors, correlates with disease progression, and predicts cardiovascular events. Therapies for atherosclerosis have been developed, therefore, that are directed towards improving endothelial function.

Gasotransmitters in Vascular Complications of Diabetes

In the past decades three gaseous signaling molecules-so-called gasotransmitters-have been identified: nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S). These gasotransmitters are endogenously produced by different enzymes in various cell types and play an important role in physiology and disease. Despite their specific functions, all gasotransmitters share the capacity to reduce oxidative stress, induce angiogenesis, and promote vasorelaxation. In patients with diabetes, a lower bioavailability of the different gasotransmitters is observed when compared with healthy individuals. As yet, it is unknown whether this reduction precedes or results from diabetes. The increased risk for vascular disease in patients with diabetes, in combination with the extensive clinical, financial, and societal burden, calls for action to either prevent or improve the treatment of vascular complications. In this Perspective, we present a concise overview of the current data on the bioavailability of gasotransmitters in diabetes and their potential role in the development and progression of diabetes-associated microvascular (retinopathy, neuropathy, and nephropathy) and macrovascular (cerebrovascular, coronary artery, and peripheral arterial diseases) complications. Gasotransmitters appear to have both inhibitory and stimulatory effects in the course of vascular disease development. This Perspective concludes with a discussion on gasotransmitter-based interventions as a therapeutic option.

Antioxidant activity of methanol extracts of different parts of Lantana camara

OBJECTIVE

To investigate the antioxidant activity of methanolic extracts of Lantana camara (L. camara) various parts and the determination of their total phenolics content.

METHODS

The extract was screened for possible antioxidant activities by free radical scavenging activity(DPPH), xanthine oxidase inhibition activity and Griess-Ilosvay method.

RESULTS

The results showed that all the plant parts possessed antioxidant properties including radical scavenging, xanthine oxidase inhibition and nitrites scavenging activities. The antioxidative activities were correlated with the total phenol. The leaves extract of L. camara was more effective than that of other parts.

CONCLUSIONS

This study suggests that L. camara extracts exhibit great potential for antioxidant activity and may be useful for their nutritional and medicinal functions.

Crosstalk between advanced glycation end products (AGEs)-receptor RAGE axis and dipeptidyl peptidase-4-incretin system in diabetic vascular complications

Advanced glycation end products (AGEs) consist of heterogenous group of macroprotein derivatives, which are formed by non-enzymatic reaction between reducing sugars and amino groups of proteins, lipids and nucleic acids, and whose process has progressed at an accelerated rate under diabetes. Non-enzymatic glycation and cross-linking of protein alter its structural integrity and function, contributing to the aging of macromolecules. Furthermore, engagement of receptor for AGEs (RAGE) with AGEs elicits oxidative stress generation and subsequently evokes proliferative, inflammatory, and fibrotic reactions in a variety of cells. Indeed, accumulating evidence has suggested the active involvement of accumulation of AGEs in diabetes-associated disorders such as diabetic microangiopathy, atherosclerotic cardiovascular diseases, Alzheimer's disease and osteoporosis. Glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are incretins, gut hormones secreted from the intestine in response to food intake, both of which augment glucose-induced insulin release, suppress glucagon secretion, and slow gastric emptying. Since GLP-1 and GIP are rapidly degraded and inactivated by dipeptidyl peptidase-4 (DPP-4), inhibition of DPP-4 and/or DPP-4-resistant GLP-1 analogues have been proposed as a potential target for the treatment of diabetes. Recently, DPP-4 has been shown to cleave multiple peptides, and blockade of DPP-4 could exert diverse biological actions in GLP-1- or GIP-independent manner. This article summarizes the crosstalk between AGEs-RAGE axis and DPP-4-incretin system in the development and progression of diabetes-associated disorders and its therapeutic intervention, especially focusing on diabetic vascular complications.

Ratio of serum levels of AGEs to soluble form of RAGE is a predictor of endothelial function

OBJECTIVE

Advanced glycation end products (AGEs) and their specific receptor, the receptor for AGEs (RAGE), play an important role in atherosclerosis. Recently, a soluble form of RAGE (sRAGE) has been identified in human serum. However, the role of sRAGE in cardiovascular disease is still controversial. There is no information on the association between simultaneous measurements of AGEs and sRAGE and vascular function. In this study, we evaluated the associations between serum levels of AGEs and sRAGE, ratio of AGEs to sRAGE, and vascular function.

RESEARCH DESIGN AND METHODS

We measured serum levels of AGEs and sRAGE and assessed vascular function by measurement of flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation in 110 subjects who underwent health examinations. Multivariate regression analyses were performed to identify factors associated with vascular function.

RESULTS

Univariate regression analysis revealed that FMD correlated with age, BMI, systolic blood pressure, diastolic blood pressure, heart rate, triglycerides, HDL cholesterol, glucose, smoking pack-years, nitroglycerine-induced vasodilation, serum levels of AGEs and sRAGE, and ratio of AGEs to sRAGE. Multivariate analysis revealed that the ratio of AGEs to sRAGE remained an independent predictor of FMD, while serum level of AGEs alone or sRAGE alone was not associated with FMD.

CONCLUSIONS

These findings suggest that sRAGE may have a counterregulatory mechanism that is activated to counteract the vasotoxic effect of the AGE-RAGE axis. The ratio of AGEs to sRAGE may be a new chemical biomarker of endothelial function.

Aging in blood vessels. Medicinal agents FOR systemic arterial hypertension in the elderly

Aging impairs blood vessel function and leads to cardiovascular disease. The mechanisms underlying the age-related endothelial, smooth muscle and extracellular matrix vascular dysfunction are discussed. Vascular dysfunction is caused by: (1) Oxidative stress enhancement. (2) Reduction of nitric oxide (NO) bioavailability, by diminished NO synthesis and/or augmented NO scavenging. (3) Production of vasoconstrictor/vasodilator factor imbalances. (4) Low-grade pro-inflammatory environment. (5) Impaired angiogenesis. (6) Endothelial cell senescence. The aging process in vascular smooth muscle is characterized by: (1) Altered replicating potential. (2) Change in cellular phenotype. (3) Changes in responsiveness to contracting and relaxing mediators. (4) Changes in intracellular signaling functions. Systemic arterial hypertension is an age-dependent disorder, and almost half of the elderly human population is hypertensive. The influence of hypertension on the aging cardiovascular system has been studied in models of hypertensive rats. Treatment for hypertension is recommended in the elderly. Lifestyle modifications, natural compounds and hormone therapies are useful for initial stages and as supporting treatment with medication but evidence from clinical trials in this population is needed. Since all antihypertensive agents can lower blood pressure in the elderly, therapy should be based on its potential side effects and drug interactions.

Inhibition of JNK phosphorylation by a novel curcumin analog prevents high glucose-induced inflammation and apoptosis in cardiomyocytes and the development of diabetic cardiomyopathy

Hyperglycemia-induced inflammation and apoptosis have important roles in the pathogenesis of diabetic cardiomyopathy. We recently found that a novel curcumin derivative, C66, is able to reduce the high glucose (HG)-induced inflammatory response. This study was designed to investigate the protective effects on diabetic cardiomyopathy and its underlying mechanisms. Pretreatment with C66 significantly reduced HG-induced overexpression of inflammatory cytokines via inactivation of nuclear factor-κB in both H9c2 cells and neonatal cardiomyocytes. Furthermore, we showed that the inhibition of Jun NH2-terminal kinase (JNK) phosphorylation contributed to the protection of C66 from inflammation and cell apoptosis, which was validated by the use of SP600125 and dominant-negative JNK. The molecular docking and kinase activity assay confirmed direct binding of C66 to and inhibition of JNK. In mice with type 1 diabetes, the administration of C66 or SP600125 at 5 mg/kg significantly decreased the levels of plasma and cardiac tumor necrosis factor-α, accompanied by decreasing cardiac apoptosis, and, finally, improved histological abnormalities, fibrosis, and cardiac dysfunction without affecting hyperglycemia. Thus, this work demonstrated the therapeutic potential of the JNK-targeting compound C66 for the treatment of diabetic cardiomyopathy. Importantly, we indicated a critical role of JNK in diabetic heart injury, and suggested that JNK inhibition may be a feasible strategy for treating diabetic cardiomyopathy.