In vitro antioxidant properties of dantrolene sodium

Green synthesized Cobalt oxide nanoparticles using Curcuma longa for anti-oxidant, antimicrobial, dye degradation and anti-cancer property

In the present study, cobalt oxide nanoparticles have been synthesized using the root extract of Curcuma longa in a manner that is both environmentally friendly and economical. Initially, the synthesized nanoparticles were characterized using a UV-Vis spectroscopy analysis, in which plasma resonance at 345 nm was observed, which confirmed that CL-Cobalt oxide nanoparticles were synthesized. While FTIR analysis showed a peak at 597.37 cm-1 indicating Co-O stretching vibration. In addition, DLS, SEM and XRD analyses confirmed the synthesis of polydispersed (average size distribution of 97.5 ± 35.1 nm), cubic phase structure, and spherical-shaped CL-Cobalt oxide nanoparticles. CL-Cobalt oxide nanoparticles synthesized from green materials showed antioxidant and antimicrobial properties. CL-Cobalt oxide nanoparticles exhibited antibacterial activity against Gram negative (Klebsiella pneumoniae and Escherichia coli) and Gram positive bacteria (Bacillus subtilis, Staphylococcus aureus), while CL-Cobalt oxide nanoparticles additionally displayed significant antifungal activity against Aspergillus niger. CL-Cobalt oxide also showed application in a bioremediation perspective by showing strong photocatalytic degradation of methyl red, methyl orange and methyl blue dye. In addition, CL-Cobalt oxide also demonstrated anticancer activity against MDA-MB-468 cancer cell lines with an IC50 value of 150.8 μg/ml. Therefore, this is the first and foremost report on CL-Cobalt oxide nanoparticles synthesized using Curcuma longa showing antioxidant, antibacterial, antifungal, dye degradation and anticancer applications.

Dantrolene inhibits lysophosphatidylcholine-induced valve interstitial cell calcific nodule formation via blockade of the ryanodine receptor

Calcific aortic valve disease (CAVD), a fibrocalcific thickening of the aortic valve leaflets causing obstruction of the left ventricular outflow tract, affects nearly 10 million people worldwide. For those who reach end-stage CAVD, the only treatment is highly invasive valve replacement. The development of pharmaceutical treatments that can slow or reverse the progression in those affected by CAVD would greatly advance the treatment of this disease. The principal cell type responsible for the fibrocalcific thickening of the valve leaflets in CAVD is valvular interstitial cells (VICs). The cellular processes mediating this calcification are complex, but calcium second messenger signaling, regulated in part by the ryanodine receptor (RyR), has been shown to play a role in a number of other fibrocalcific diseases. We sought to determine if the blockade of calcium signaling in VICs could ameliorate calcification in an in vitro model. We previously found that VICs express RyR isotype 3 and that its modulation could prevent VIC calcific nodule formation in vitro. We sought to expand upon these results by further investigating the effects of calcium signaling blockade on VIC gene expression and behavior using dantrolene, an FDA-approved pan-RyR inhibitor. We found that dantrolene also prevented calcific nodule formation in VICs due to cholesterol-derived lysophosphatidylcholine (LPC). This protective effect corresponded with decreases in intracellular calcium flux, apoptosis, and ACTA2 expression but not reactive oxygen species formation caused by LPC. Interestingly, dantrolene increased the expression of the regulator genes RUNX2 and SOX9, indicating complex gene regulation changes. Further investigation via RNA sequencing revealed that dantrolene induced several cytoprotective genes that are likely also responsible for its attenuation of LPC-induced calcification. These results suggest that RyR3 is a viable therapeutic target for the treatment of CAVD. Further studies of the effects of RyR3 inhibition on CAVD are warranted.

Use of Purslane (Portulaca oleracea) Extracts and Cysteine in Diluents to Improve the Cryopreserved Quality of Goat Sperm

Highlights Using cysteine and purslane extracts in extenders improved significantly the post-thaw sperm characteristics. Sperm viability, DNA integrity, and mitochondrial activity demonstrate an improvement in post-thaw sperm. Malondialdehyde production was decreased based on the positive effects of treated extenders. The obtained results demonstrate that supplementation of 50 μg/mL of purslane methanolic extract with cysteine to freezing extenders was significantly superior compared with other treatments.

Green coffee methanolic extract and silymarin protect against CCl4-induced hepatotoxicity in albino male rats

BACKGROUND

During the last few decades, patients worldwide have been interested in using alternative medicine in treating diseases to avoid the increased side effects of chemical medications. Green coffee is unroasted coffee seeds that have higher amounts of chlorogenic acid compared to roasted coffee. Green coffee was successfully used to protect against obesity, Alzheimer disease, high blood pressure and bacterial infection.

METHODS

This study aimed to investigate the probable protective activity of the green coffee methanolic extract, silymarin and their combination on CCl₄-induced liver toxicity in male rats. Thirty Sprague - Dawley male albino rats were divided into 5 groups; control negative (G1) just got the vehicle (olive oil) and the other four groups received CCl₄ dissolved in olive oil through an intraperitoneal injection and were divided into untreated control positive group (G2), the third group (G3) was treated with green coffee methanolic extract, the fourth group (G4) was treated with silymarin, and the fifth group (G5) was treated with a combination of green coffee methanolic extract and silymarin.

RESULTS

In the positive control group treated with CCl₄ (G2), the CCl₄-induced toxicity increased lipid peroxidation, IL-6, kidney function parameters, liver function enzymes, total cholesterol, triglycerides and low-density lipoproteins, and decreased irisin, antioxidants, CYP450 and high-density lipoprotein levels. Hepatic tissues were also injured. However, treating the injured rats in G3, G4 and G5 significantly improved the altered parameters and hepatic tissues.

CONCLUSIONS

Green coffee methanolic extract, silymarin, and their combination succeeded in protecting the male rats against CCl4 hepatotoxicity due to their antioxidant activity. Effect of green coffee methanolic extract mixed with silymarin in G5 was more efficient than that of green coffee methanolic extract in G3 or silymarin in G4.

Phoenix dactylifera L. Seed Extract Exhibits Antioxidant Effects and Attenuates Melanogenesis in B16F10 Murine Melanoma Cells by Downregulating PKA Signaling

Background: The mode of action of Phoenix dactylifera seed extract in skin care has never been explored. Methods: P. dactylifera L. seeds were extracted by ultrasonic extraction. The antioxidant characteristics of the extract were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-di-(3-ethylbenzthiazoline sulfonic acid) (ABTS⁺) assays and scavenging methods. The total phenolic content, reducing capacity, iron (II) ion-chelation, and intracellular reactive oxygen species (ROS)-scavenging capacities were also investigated. The effects of P. dactylifera L. seed extract on melanogenesis were evaluated spectrophotometrically by a mushroom tyrosinase activity assay, determination of intracellular tyrosinase activity, and melanin content. The expression levels of melanogenesis-related proteins were analyzed by Western blotting. Results: The results revealed that the P. dactylifera L. seed extract exerted apparent antioxidant capacity and significantly decreased intracellular ROS content at concentrations of 0.245 and 0.49 (mg/mL). Furthermore, the extract decreased the expression of melanocortin 1 receptor (MC1R), microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP1), and tyrosinase-related protein-2 (TRP2), and inhibited melanogenesis in B16F10 cells. Conclusions: Our results revealed that P. dactylifera L. seed extract attenuated melanogenesis in B16F10 cells by downregulating protein kinase A (PKA) signaling pathways. Hence, the extract could be used as a type of skin-whitening agent in skin care products.

Oxidation of Ryanodine Receptors Promotes Ca2+ Leakage and Contributes to Right Ventricular Dysfunction in Pulmonary Hypertension

Right ventricular (RV) failure is a major cause of death in patients with pulmonary arterial hypertension, and the mechanism of RV failure remains unclear. While the malfunction of RyR2 (ryanodine receptor type 2) on sarcoplasmic reticulum (SR) and aberrant Ca²⁺ cycling in cardiomyocytes have been recognized in some cardiovascular diseases, their roles in RV failure secondary to pulmonary arterial hypertension require further investigation. In a monocrotaline-induced rat model of pulmonary arterial hypertension, the RV remodeling process was divided into normal, compensated, and decompensated stages according to the hemodynamic and morphological parameters. In both compensated and decompensated stages, significant diastolic SR Ca²⁺ leakage was detected along with reduced intracellular Ca²⁺ transient amplitude and SR Ca²⁺ contents in RV myocytes. RyR2 protein levels decreased progressively during the process, and the thiol oxidation proportions of RyR2 were higher in compensated and decompensated stages than in normal stage. Inhibition of RyR2 oxidation by dithiothreitol or repairing RyR2 directly by dantrolene could restore Ca²⁺ homeostasis in RV myocytes. Daily intraperitoneal injection of dantrolene delayed decompensation progression and significantly improved the survival rate of pulmonary hypertension rats in decompensated stage (79.3% versus 55.9%; P=0.026). Our findings suggest that diastolic SR Ca²⁺ leakage via oxidized RyR2 facilitates the development of RV failure. Dantrolene can inhibit diastolic SR Ca²⁺ leakage in RV cardiomyocytes, delay right cardiac dysfunction, and improve the survival of rats with pulmonary arterial hypertension.

Seasonal Variability of Juniperus communis L. Berry Ethanol Extracts: 1. In Vitro Hydroxyl Radical Scavenging Activity

In the present study, in vitro hydroxyl radical scavenging activities, total phenols and terpene contents in 70% ethanol extracts were evaluated. Samples of crushed (CB) and non-crushed ripe juniper berries (NCB) collected at five localities in North-East Slovakia during the years 2012-2014 were compared. Standard or modified methods for determining phytochemical and antioxidant activity were used together with a novel method for the evaluation of the results after the correction of the measured values per gram of dry matter (DM). Statistically significantly higher DM contents (average values for three years) were found in the CB extracts (ranging from 18.86 to 21.91 mg/mL) in comparison to those for NCB (ranging from 2.59 to 9.90 mg/mL). Depending on the localities and years, the hydroxyl radical scavenging activity ranged from 15.52 to 32.85% for NCB and from 65.59 to 88.12% for CB, respectively. The contents of total phenols ranged from 43.75 to 246.75 mg gallic acid equivalents (GAE)/L (NCB) and from 151.84 to 278.19 mg GAE/L (CB), respectively. However, the higher content of total phenols per gram of DM was found in the NCB extracts (8.49-42.23 mg GAE/g DM) and then in CB (6.87-18.77 GAE/g DM). The results obtained in this study showed a higher efficiency for extraction from juniper berries in 70% ethanol if the pericarp was disrupted in comparison to that achieved with the maceration of intact berries.

Ephedrine causes liver toxicity in SD rats via oxidative stress and inflammatory responses

Ephedrine abuse has spread in many parts of the world and severely threatens human health. The mechanism of ephedrine-induced toxicity still remains unclear. This study was performed to investigate the effects of ephedrine treatment on the liver and explore the underlying mechanisms. Sprague Dawley rats were divided into saline and ephedrine groups. Rats were treated with ephedrine at 20 mg/kg or 40 mg/kg ( n = 10) by oral gavage daily for 7 days. Pathological changes were examined by hematoxylin and eosin staining and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling assay. Enzyme-linked immunosorbent assays were used to measure the liver functional markers, oxidative stress markers, and inflammatory cytokines. Real-time polymerase chain reaction and Western blot were used to measure gene and protein expression, respectively. Our data showed that ephedrine treatment increased hepatocellular cell apoptosis and impaired liver function. Moreover, ephedrine treatment increased oxidative stress and inflammatory responses, which may be due to the increase of transforming growth factor β (TGF-β)/Smad3 expression. Our study demonstrated that short-term treatment of ephedrine caused liver toxicity in rats through regulating TGF-β/Smad pathway.

Ephedrine causes retinal damage in SD rats associating with JAK2/STAT3 pathway

PURPOSE

Ephedrine has various side effects in the cardiovascular and nervous systems. However, the cellular mechanism of toxicity remains unknown, specifically on the retina. This study was to investigate effects of ephedrine on the retina and explore the underlying mechanisms.

METHODS

Sprague Dawley rats were treated with ephedrine (n = 10) or saline (n = 10) by oral gavage for seven days. The retinal morphology was evaluated by Toluidine blue staining. Apoptosis-related markers were detected in the retinal lysate. Enzyme-linked immunosorbent assays were used to measure neurotransmitters and oxidative stress markers. Real-time PCR and western blot were used to measure gene and protein expression, respectively.

RESULTS

Our results demonstrated that ephedrine induced apoptosis in the retina, increased dopamine level as well as oxidative stress, and down-regulated the Jak2/Stat3 gene expression as well as protein expression of p-JAK2/p-STAT3.

CONCLUSIONS

Our study indicated that ephedrine treatment caused retinal damage in SD rats, which may be associated with the JAK2/STAT3 pathway.

Inhibition effects of isoproterenol, chlorpromazine, carbamazepine, tamoxifen drugs on glutathione S-transferase, cholinesterases enzymes and molecular docking studies

Nowadays, inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and glutathione S-transferases (GSTs) have been a very crucial issue for pharmacological treatments of several disasters. Herein, we investigated inhibition effects of Tamoxifen (TAM), Isoprenaline (ISO), Chlorpromazines (CPZ) and Carbamazepine (CBZ) on GST, AChE, BChE and then molecular structures and active sides of the tested drugs by molecular docking process. The enzyme activity results showed that nearly the whole tested drugs inhibited GST, BChE, AChE efficiently. Chlorpromazine was found to be the best inhibitor for the GST enzyme and the Ki value of this drug was found to be 42.83 ± 8.52 nM. Besides, Isoproterenol drug with the Ki value of 51.80 ± 9.44 nM was found to be the most effective inhibitor on the AChE enzyme. Molecular docking studies showed that the receptor-binding sites of GST, AChE, and BChE were found to 1.069, 1.090, and 1.15 of Sitecore and 0.992, 1.113, and 1.217 of Dscore, respectively. The method was validated by doing validation studies and these validations revealed that re-docked ligands located a very closed position with co-crystallized ligand into the active site for all receptors. Calculation studies for determining the possible enzyme inhibition mechanism with the used drugs revealed that amino and aromatic ring in the structure of the drugs used are effective in inhibition reactions.Communicated by Ramaswamy H. Sarma.

Application of Box-Behnken Design and Desirability Function for Green Prospection of Bioactive Compounds from Isochrysis galbana

A microalga, Isochrysis galbana, was chosen in this study for its potent natural antioxidant composition. A broad bioactive compounds spectrum such as carotenoids, fatty acid polyunsaturated (PUFA), and antioxidant activity are described with numerous functional properties. However, most of the optimization of extraction use toxic solvents or consume a lot of it becoming an environmental concern. In this research, a Box-Behnken design with desirability function was used to prospect the bioactive composition by supercritical fluid extraction (SFE) after performing the kinetics curve to obtain the optimal extraction time minimizing operational costs in the process. The parameters studied were: pressure (20–40 MPa), temperature (40–60 °C), and co-solvent (0–8% ethanol) with a CO2 flow rate of 7.2 g/min for 120 min. The response variables evaluated in I. galbana were extraction yield, carotenoids content and recovery, total phenols, antioxidant activity (TEAC method, trolox equivalents antioxidant capacity method), and fatty acid profile and content. In general, improvement in all variables was observed using an increase in ethanol concentration used as a co-solvent (8% v/v ethanol) high pressure (40 MPa), and moderately high temperature (50 °C). The fatty acids profile was rich in polyunsaturated fatty acid (PUFA) primarily linoleic acid (C18:2) and linolenic acid (C18:3). Therefore, I. galbana extracts obtained by supercritical fluid extraction showed relevant functional ingredients for use in food and nutraceutical industries.

Antioxidants and antioxidant methods: an updated overview

Antioxidants had a growing interest owing to their protective roles in food and pharmaceutical products against oxidative deterioration and in the body and against oxidative stress-mediated pathological processes. Screening of antioxidant properties of plants and plant-derived compounds requires appropriate methods, which address the mechanism of antioxidant activity and focus on the kinetics of the reactions including the antioxidants. Many studies evaluating the antioxidant activity of various samples of research interest using different methods in food and human health have been conducted. These methods are classified, described, and discussed in this review. Methods based on inhibited autoxidation are the most suited for termination-enhancing antioxidants and for chain-breaking antioxidants, while different specific studies are needed for preventive antioxidants. For this purpose, the most common methods used in vitro determination of antioxidant capacity of food constituents were examined. Also, a selection of chemical testing methods was critically reviewed and highlighted. In addition, their advantages, disadvantages, limitations and usefulness were discussed and investigated for pure molecules and raw extracts. The effect and influence of the reaction medium on the performance of antioxidants are also addressed. Hence, this overview provides a basis and rationale for developing standardized antioxidant methods for the food, nutraceuticals, and dietary supplement industries. In addition, the most important advantages and shortcomings of each method were detected and highlighted. The chemical principles of these methods are outlined and critically discussed. The chemical principles of methods of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonate) radical (ABTS^·+) scavenging, 1,1-diphenyl-2-picrylhydrazyl (DPPH·) radical scavenging, Fe³⁺-Fe²⁺ transformation assay, ferric reducing antioxidant power (FRAP) assay, cupric ions (Cu²⁺) reducing power assay (Cuprac), Folin-Ciocalteu reducing capacity (FCR assay), peroxyl radical (ROO·), superoxide radical anion (O₂^·-), hydrogen peroxide (H₂O₂) scavenging assay, hydroxyl radical (OH·) scavenging assay, singlet oxygen (¹O₂) quenching assay, nitric oxide radical (NO·) scavenging assay and chemiluminescence assay are outlined and critically discussed. Also, the general antioxidant aspects of main food components were discussed by a number of methods, which are currently used for the detection of antioxidant properties of food components. This review consists of two main sections. The first section is devoted to the main components in the food and pharmaceutical applications. The second general section comprises some definitions of the main antioxidant methods commonly used for the determination of the antioxidant activity of components. In addition, some chemical, mechanistic and kinetic basis, and technical details of the used methods are given.

Dantrolene Attenuates Cardiotoxicity of Doxorubicin Without Reducing its Antitumor Efficacy in a Breast Cancer Model

Dysregulation of calcium homeostasis is a major mechanism of doxorubicin (DOX)-induced cardiotoxicity. Treatment with DOX causes activation of sarcoplasmic reticulum (SR) ryanodine receptor (RYR) and rapid release of Ca²⁺ in the cytoplasm resulting in depression of myocardial function. The aim of this study was to examine the effect of dantrolene (DNT) a RYR blocker on both the cardiotoxicity and antitumor activity of DOX in a rat model of breast cancer. Female F344 rats with implanted MAT B III breast cancer cells were randomized to receive intraperitoneal DOX twice per week (12 mg/kg total dose), 5 mg/kg/day oral DNT or a combination of DOX + DNT for 3 weeks. Echocardiography and blood troponin I levels were used to measure myocardial injury. Hearts and tumors were evaluated for histopathological alterations. Blood glutathione was assessed as a measure of oxidative stress. The results showed that DNT improved DOX-induced alterations in the echocardiographic parameters by 50%. Histopathologic analysis of hearts showed reduced DOX induced cardiotoxicity in the group treated with DOX + DNT as shown by reduced interstitial edema, cytoplasmic vacuolization, and myofibrillar disruption, compared with DOX-only–treated hearts. Rats treated with DNT lost less body weight, had higher blood GSH levels and lower troponin I levels than DOX-treated rats. These data indicate that DNT is able to provide protection against DOX cardiotoxicity without reducing its antitumor activity. Further studies are needed to determine the optimal dosing of DNT and DOX in a tumor-bearing host.

Novel Amide Derivatives as Potent Tyrosinase Inhibitors; In-vitro, In-vivo Antimelanogenic Activity and Computational Studies

BACKGROUND

Tyrosinase is involved in the melanin biosynthesis and the abnormal accumulation of melanin pigments leading to hyperpigmentation disorders. Controlling the melanogenesis could be an important strategy for treating abnormal pigmentation.

METHODS

In the present study, a series of amide derivatives (3a-e and 5a-e) were synthesized aiming to inhibit tyrosinase activity and melanin production. All derivatives were screened for tyrosinase inhibition in a cell-free system. The possible interactions of amide derivatives with tyrosinase enzyme and effect of these interactions on tyrosinase structure were checked by molecular docking in silico and by Circular Dichroism (CD) studies, respectively. The most potent amide derivative (5c) based on cell-free experiments, was further tested for cellular ROS inhibition and for tyrosinase activity using mouse skin melanoma (B16F10) cells.

RESULTS

The tyrosinase inhibitory concentration (IC50) for tested compounds was observed between the range of 68 to 0.0029 µg/ml with a lowest IC50 value of compound 5c which outperforms the reference arbutin and kojic acid. The cellular tyrosinase activity and melanin quantification assay demonstrate that 15µg/ml of 5c attenuates 36% tyrosinase, 24% melanin content of B16F10 cells without significant cell toxicity. Moreover, the zebrafish in vivo assay reveals that 5c effectively reduces melanogenesis without perceptible toxicity. Furthermore, the molecular docking demonstrates that compound 5c interacts with copper ions and multiple amino acids in the active site of tyrosinase with best glide score (-5.387 kcal/mol), essential for mushroom tyrosinase inhibition and the ability to diminish the melanin synthesis in-vitro and in-vivo.

CONCLUSION

Thus, we propose compound 5c as a potential candidate to control tyrosinase rooted hyperpigmentation in the future.

Synthesis, computational studies, tyrosinase inhibitory kinetics and antimelanogenic activity of hydroxy substituted 2-[(4-acetylphenyl)amino]-2-oxoethyl derivatives

The over expression of melanogenic enzymes like tyrosinase caused many hyperpigmentaion disorders. The present work describes the synthesis of hydroxy substituted 2-[(4-acetylphenyl)amino]-2-oxoethyl derivatives 3a-e and 5a-e as antimelanogenic agents. The tyrosinase inhibitory activity of synthesized derivatives 3a-e and 5a-e was determined and it was found that derivative 5c possesses excellent activity with IC50 = 0.0089 µM compared to standard kojic acid (IC50 = 16.69 µM). The presence of hydroxyl groups at the ortho and the para position of cinnamic acid phenyl ring in compound 5c plays a vital role in tyrosinase inhibitory activity. The compound 5d also exhibited good activity (IC50 = 8.26 µM) compared to standard kojic acid. The enzyme inhibitory kinetics results showed that compound 5c is a competitive inhibitor while 5d is a mixed-type inhibitor. The mode of binding for compounds 5c and 5d with tyrosinase enzyme was also assessed and it was found that both derivatives irreversibly bind with target enzyme. The molecular docking and molecular dynamic simulation studies were also performed to find the position of attachment of synthesized compounds at tyrosinase enzyme (PDB ID 2Y9X). The results showed that all of the synthesized compounds bind well with the active binding sites and most potent derivative 5c formed stable complex with target protein. The cytotoxicity results showed that compound 5c is safe at a dose of 12 µg/mL against murine melanoma (B16F10) cells. The same dose of 5c was selected to determine antimelanogenic activity; the results showed that it produced antimelenogenic effects in murine melanoma (B16F10) cells. Based on our investigations, it was proposed that compound 5c may serve as a lead structure to design more potent antimelanogenic agents.

A Prospective Repurposing of Dantrolene as a Multitarget Agent for Alzheimer's Disease

The orphan drug dantrolene (DAN) is the only therapeutic treatment for malignant hyperthermia (MH), a pharmacogenetic pathology affecting 0.2 over 10,000 people in the EU. It acts by inhibiting ryanodine receptors, which are responsible for calcium recruitment in striatal muscles and brain. Because of its involvement in calcium homeostasis, DAN has been successfully investigated for its potential as neuroprotecting small molecule in several animal models of Alzheimer’s disease (AD). Nevertheless, its effects at a molecular level, namely on putative targets involved in neurodegeneration, are still scarcely known. Herein, we present a prospective study on repurposing of DAN involving, besides the well-known calcium antagonism, inhibition of monoamine oxidase B and acetylcholinesterase, cytoprotection from oxidative insult, and activation of carnitine/acylcarnitine carrier, as concurring biological activities responsible for neuroprotection.

Values of antioxidant activities (ABTS and DPPH) and ferric reducing and chelating powers of gamma-irradiated rosemary extract

This study was carried out to evaluate the effect of the various gamma dose irradiations on the antioxidant activity of rosemary PBS (phosphate-buffered saline) extract. The PBS extract of rosemary was irradiated with gamma rays at the doses of 10, 20, 30, 40 and 50 kGy, and their antioxidant activities were investigated by DPPH (1,1-diphenyl-2-picrylhydrazyl), radical cation ABTS•+ (2,2-Azino-Bis (3-Ethylbenzthiazoline-6-Sulfonic Acid), Diammonium Salt), ferric reducing antioxidant power assay (FRAP) and ferric chelating capacity using ferrozine. The scavenging activities of gamma irradiated rosemary were observed to be significantly higher at 30 and 40 kGy using both methods, DPPH and ABST. Also, the reducing power values of 30 kGy gamma irradiated rosemary were higher than that of non-irradiated (P < 0.05) and the other doses of irradiation could not make any significant difference in reducing power of non-irradiated rosemary. The gamma irradiation of rosemary (at 10–50 kGy), significantly increased the Fe2+ chelating activity compared to non-irradiated rosemary while increasing the absorbed doses reduced Fe2+ chelating activity in rosemary (P < 0.05). There is no significant difference in the rosemary irradiated with 10 kGy and 30 kGy. The gamma irradiated rosemary showed higher antioxidant activities at doses of 30 kGy (79.5 %) and 40 kGy (80 %) with DPPH method, while slightly lower activities were recorded at doses of 30 kGy (34.8 %) and 40 kGy (34.2 %) with ABTS test. Also, results indicate that the 30 kGy might be an effective dose with maximum enhancement in the antioxidant properties of the gamma irradiated rosemary.

Atrial Infarction-Induced Spontaneous Focal Discharges and Atrial Fibrillation in Sheep: Role of Dantrolene-Sensitive Aberrant Ryanodine Receptor Calcium Release

BACKGROUND

The mechanisms underlying spontaneous atrial fibrillation (AF) associated with atrial ischemia/infarction are incompletely elucidated. Here, we investigate the mechanisms underlying spontaneous AF in an ovine model of left atrial myocardial infarction (LAMI).

METHODS AND RESULTS

LAMI was created by ligating the atrial branch of the left anterior descending coronary artery. ECG loop recorders were implanted to monitor AF episodes. In 7 sheep, dantrolene-a ryanodine receptor blocker-was administered in vivo during the 8-day observation period (LAMI-D, 2.5 mg/kg, IV, BID). LAMI animals experienced numerous spontaneous AF episodes during the 8-day monitoring period that were suppressed by dantrolene (LAMI, 26.1±5.1; sham, 4.3±1.1; LAMI-D, 2.8±0.8; mean±SEM episodes per sheep, P<0.01). Optical mapping showed spontaneous focal discharges (SFDs) originating from the ischemic/normal-zone border. SFDs were calcium driven, rate dependent, and enhanced by isoproterenol (0.03 µmol/L, from 210±87 to 3816±1450, SFDs per sheep) but suppressed by dantrolene (to 55.8±32.8, SFDs per sheep, mean±SEM). SFDs initiated AF-maintaining reentrant rotors anchored by marked conduction delays at the ischemic/normal-zone border. NOS1 (NO synthase-1) protein expression decreased in ischemic zone myocytes, whereas NADPH (nicotinamide adenine dinucleotide phosphate, reduced form) oxidase and xanthine oxidase enzyme activities and reactive oxygen species (DCF [6-carboxy-2',7'-dichlorodihydrofluorescein diacetate]-fluorescence) increased. CaM (calmodulin) aberrantly increased [³H]ryanodine binding to cardiac RyR2 (ryanodine receptors) in the ischemic zone. Dantrolene restored the physiological binding of CaM to RyR2.

CONCLUSIONS

Atrial ischemia causes spontaneous AF episodes in sheep, caused by SFDs that initiate reentry. Nitroso-redox imbalance in the ischemic zone is associated with intense reactive oxygen species production and altered RyR2 responses to CaM. Dantrolene administration normalizes the CaM response, prevents LAMI-related SFDs, and AF initiation. These findings provide novel insights into the mechanisms underlying ischemia-related atrial arrhythmias.

Antioxidant and Antimelanogenic Activities of Compounds Isolated from the Aerial Parts of Achillea alpina L

Achillea alpina is widely distributed in Korea and is often used as a folk medicine for stomach disorders. Although a previous study isolated antioxidant compounds (flavonoid O-glucoside, sesquiterpene) from this plant, no systematic study of its chemical constituents had been reported. The present study aimed to identify the phytochemicals present in a methanol extract of A. alpina, assess their potential antioxidant activities in vitro, and determine their effects on melanogenesis in B16F10 melanoma cells. Column chromatographic separation of aqueous fractions of A. alpina led to the isolation of 17 compounds. The chemical structures of these compounds were determined using spectroscopic data from electrospray ionization-mass spectrometry and nuclear magnetic resonance. To the best of our knowledge, the present study is the first to identify compounds 2-10 and 12-17 in A. alpina. Furthermore, compound 6 possessed powerful antioxidant activity, while compound 15 suppressed intracellular tyrosinase activity and thus reduced melanogenesis in B16F10 cells. Therefore, our research suggested that these naturally occurring compounds have the potential to reduce oxidative stress and promote skin whitening. Further investigations will be required to elucidate the mechanisms underlying the antioxidant and antityrosinase activities of these compounds.

Determination and tissue distribution studies of dantrolene sodium with hydroxypropyl-β-cyclodextrin in rat tissue by HPLC/MS/MS

The established analytical method for determining the concentration of dantrolene sodium (Da) in rat tissues by HPLC/MS/MS technique was successfully applied to tissue distribution studies of Da in rats. Tissue homogenate samples were pretreated by protein precipitation with pre-cooled methanol. Chromatographic separation was achieved on an Acquity HPLC column (Kromat Universil XB-C₁₈ , 2.1 × 150 mm, 3 μm). Mass spectrometry was conducted with an electrospray ionization interface in negative ionization mode and multiple reaction monitoring was used for quantitative analysis. The results showed that Da was rapidly and widely distributed in tissues and reached the maximum concentration within 0.5 h in all tissues after oral administration of Da-hydroxypropyl-β-cyclodextrin (DHC). It was then metabolized by liver and finally excreted from kidney,which indicated that DHC inclusion complex has better absorption and higher oral bioavailability than Da. The results also provided evidence for the safety and effectiveness of drug clinical application.

Changes in radical scavenging activity of normal, endoreduplicated and depolyploid root tip cells of Allium cepa

The plant cell responds to abiotic stress conditions by adjusting its cellular metabolism and various defensive mechanisms. Cellular metabolism involves changes in the cell cycle, in which the cell undergoes repeated rounds of endocycles leading to polyploidization. Defense mechanisms such as role of antioxidants are a key to understand plant adaptation. The present work describes endoreduplication and radical scavenging activity as two different defense mechanisms adapted by plants for their survival under stress condition. The work describes linkage of these two processes with each other under abiotic stress. Endoreduplicated root tip cells of Allium cepa were depolyploidized by exogenous phytohormones. Further, free radical scavenging activity from normal, endoreduplicated and depolyploidized root tips cells was observed to understand the role of phytohormones. Elevated free radical scavenging potential was observed in endoreduplicated cells compared to normal and depolyploidized cells. Based on these results, it was concluded that endoreduplication and antioxidant pathways are linked with each other through phytohormonal activities. The concentration of auxin and cytokinin regulates the activity of ascorbate oxidase enzyme, which in turn maintains the concentration of AsA within the cell. AsA level directs the prolyl-hydroxylation process of cell division proteins in quiescent center cells either toward endoreduplication process or cell division process.

Formulation and evaluation of carrot seed oil-based cosmetic emulsions

The present study deals with the evaluation of antiaging potential of carrot seed oil-based cosmetic emulsions. Briefly, cosmetic emulsions composed of carrot seed oil in varying proportions (2, 4, and 6% w/v) were prepared using the hydrophile-lipophile balance (HLB) technique. Coconut oil, nonionic surfactants (Tween 80 and Span 80), and xanthan gum were used as the oil phase, emulgent, and emulsion stabilizer, respectively. The formed emulsions were evaluated for various physical, chemical, and biochemical parameters such as the zeta potential, globule size measurement, antioxidant activity, sun protection factor (SPF), skin irritation, and biochemical studies. The zeta potential values ranged from -43.2 to -48.3, indicating good stability. The polydispersity index (PDI) of various emulsion formulations ranged from 0.353 to 0.816. 1,1-Diphenyl-2-picrylhydrazyl- (DPPH) and nitric oxide-free radical scavenging activity showed the antioxidant potential of the prepared carrot seed oil emulsions. The highest SPF value (6.92) was shown by F3 having 6%w/v carrot seed oil. Histopathological data and biochemical analysis (ascorbic acid (ASC) and total protein content) suggest that these cosmetic emulsions have sufficient potential to be used as potential skin rejuvenating preparations.

Phytochemical and pharmacological status of indigenous medicinal plant Pedalium murex L.-A review

PURPOSE

Pedalium murex is a fruit-bearing annual herb, native to South India, Mexico and tropical Africa. The plant is widely used to treat numerous diseases including gastric ulcer, asthma, heart problems, anti inflammatory activity and particularly urinary disorders. Traditional medicine has become a skilled approach by means of rational values in handling a variety of diseases and developing an affordable phytotherapy. It is proclaimed that P.murex is an expensive source of unique bioactive compounds for the development of natural medicines against various diseases.

CONCLUSION

This review provides the details of ethno pharmacological importance of P. murex, as well as its composition of phytochemicals, biological activities and traditional usage. Also provides a source for future studies such as isolation of bioactive components and mechanism of action of this plant extract.

The Protective Effects of p-Coumaric Acid on Acute Liver and Kidney Damages Induced by Cisplatin

In this study, we aimed to investigate the effects of p-Coumaric acid (PCA) on cisplatin (CIS)-induced hepatotoxicity and nephrotoxicity in Wistar adult rats for 24 h compared to untreated control groups. In this experiment, 40 Wistar adult rats were utilized and divided randomly into five groups. After 24 h of CIS administration, liver and kidneys were harvested and assessed by H&amp;E staining. Also, markers for oxidative stress and antioxidants were analyzed in theses tissues. Compared to the control group, accumulation of malondialdehyde was increased in groups treated CIS, whereas superoxide dismutase activities and glutathione levels were distinctly diminished in this group. The study's histopathological findings such as hydropic degeneration, vascular congestion, sinusoidal dilatation in hepatocytes and tubular necrosis in kidneys were in accordance with the results of markers for oxidative stress. PCA may prevent hepatotoxicity and nephrotoxicity by increased antioxidant enzymes and reduced oxidant parameters.

Oxidative stress controlling agents are effective for small intestinal injuries induced by non-steroidal anti-inflammatory drugs

BACKGROUND AND AIM

Video-capsule endoscopy (VCE) has shown that intestinal ulcers are common in non-steroidal anti-inflammatory drugs (NSAIDs) users, although the mechanisms and management have not been clearly defined. To explore the contribution of oxidative stress and potential of anti-oxidants for NSAIDs-induced intestinal ulcers, we assessed human serum oxidative stress balance and the effect of anti-oxidants using a mouse model.

METHODS

A total of 30 NSAIDs users (17 aspirin and 13 non-aspirin users) received VCE. Serum reactive oxygen metabolite (d-ROM) and antioxidative OXY-adsorbent test (OXY) were measured. The indomethacin (IND)-induced mouse intestinal ulcer model was used to assess the effect of anti-oxidants. Eight-week-old mice were divided into four groups; control diet and diet including IND (N group), IND and L-carnitine (NC group), and IND and vitamin E (NE group).

RESULTS

Serum OXY levels among non-aspirin users were lower in the mucosal injuries positive group than the negative group (P < 0.05). In the mouse models, the degree of mucosal injuries was lower in NC and NE than N (P < 0.01). Serum d-ROM levels were lower in NC and NE than N (P < 0.01), and OXY levels were higher in NC than N and NE (P < 0.01). The degeneration of intestinal mitochondria was mild in NC and NE. The serum KC/CXCL-1 level and hepatic expression of the anti-oxidant molecule Gpx4 were lower in NC than N.

CONCLUSIONS

Non-aspirin NSAID-induced intestinal ulcers are related to decreased anti-oxidative stress function. Anti-oxidants, especially L-carnitine, are good candidates for intestinal ulcers.

The main constituents of Tulipa systola Stapf. roots and flowers; their antioxidant activities

People living on the mountains of the Kurdistan Region, Iraq make a large use of herbs in the local traditional medicine. Among them, Tulipa systola, which grows under and between rocks, is very popular as an anti-inflammatory remedy and pain-relief. The phytochemical study of an ethanolic extract obtained from flowers and roots of Tulip (T systola Stapf.) afforded three compounds, identified as (+)-1-O-E-feruloyl-3-O-E-p-coumaroylglycerol (1), (+)-6-tuliposide A (2), and (-)-kaempferol-3-O-rutinoside (3). The significant radical scavenging and antioxidant activity of the isolated compounds were evaluated on three tests, by determining the DPPH free radical scavenging activity, the total antioxidant activity and the hydrogen peroxide scavenging activity. Tuliposide A shows potent allergenic activity.

In vivo and In vitro Anti-Inflammatory Activity of Indazole and Its Derivatives

INTRODUCTION

The inflammatory response is closely intertwined with the process of repair. However in some diseases the inflammatory response may be exaggerated and sustained without apparent benefit and even with severe adverse complications. For decades, we have been primarily relying upon Nonsteroidal (NSAID) and Steroidal Anti-Inflammatory agents for management of various inflammatory conditions. However, adverse effects of these drugs are severe which often leads to patient's non-compliance with inadequate relief. Therefore, there has been a constant pursuit to develop newer anti - inflammatory treatment with fewer side effects.

AIM

The study was designed to investigate the possible anti- inflammatory activity of indazole, its derivatives and to further investigate the possible cellular mechanisms underlying the anti-inflammatory effect.

MATERIALS AND METHODS

Carrageenan induced hind paw oedema in rats was employed to study the acute anti-inflammatory activity of indazole and its derivatives. Further, the role of cyclooxygenase - 2, pro-inflammatory cytokines like Tumour Necrosis Factor - α, Interleukin - 1β and free radical scavenging activity (LPO, DPPH and NO) in the action of indazole and its derivatives was investigated using in vitro assays.

RESULTS

SPSS version 16.0 software was used for analyse the anti-inflamatory data. The IC50 values of indazole and its derivatives obtained in in vitro experiments were calculated by linear regression analysis. Indazole and its derivatives significantly, dose dependently and time dependently inhibited carrageenan induced hind paw oedema. In addition, the test compounds inhibited cyclooxygenase-2, pro-inflammatory cytokines and free radicals in a concentration dependent manner.

CONCLUSION

The results of the present study revealed the potential anti-inflammatory action of investigated indazoles. The inhibition of cyclooxygenase -2, cytokines and free radicals may contribute to the anti-inflammatory effect of the test compounds.

EVALUATION OF THE EFFECTS OF THE HYDRO-ETHANOLIC ROOT EXTRACT OF ZANTHOXYLUM ZANTHOXYLOIDES ON HEMATOLOGICAL PARAMETERS AND OXIDATIVE STRESS IN CYCLOPHOSPAMIDE TREATED RATS

BACKGROUND

The use of cyclophosphamide in cancer therapy is usually associated with challenging immunosuppression which exposes patients to increased risk of anemia and necessitating preventive measures during therapy. This study was carried out to investigate the efficacy of the hydro-ethanolic extract of the root of Z. zanthoxyloides in preventing and/or improving cyclophosphamide induced myelosuppression and oxidative stress in rats.

MATERIALS AND METHODS

Animals were divided into 6 groups of 6 rats each and were pretreated oral doses of 75, 150 and 225 mg/kg of the extract for 7 days and then co-administered with 2.5 mg/kg cyclophosphamide for 28 days.

RESULTS

The LD50 of the extract was found to be 1682.3 mg/kg. Phytochemical analysis of the plant extract showed the presence of tannins, saponins, alkaloids and flavonoids, glycosides, terpenoids and phenols. In the anti-oxidant enzyme assay, CAT was significantly (p < 0.05) increased for animals treated with 150 mg/kg+CP compared to 75 mg/kg+CP and 225 mg/kg+CP. GPx was significantly (p < 0.01) increased in rats treated with 75 mg/kg+CP compared to 150 mg/kg+CP and control. SOD was significantly (p < 0.01) increased in rats treated with 75 mg/kg+CP compared to the control. WBC was significantly (p < 0.05) reduced for 225 mg/kg, 225 mg/kg+CP (p < 0.001), 150 mg/kg+CP (p < 0.001), 75 mg/kg+CP (p < 0.001) and CP administered rats (p < 0.001) respectively compared to the control. LDL and CHOL were significantly reduced (p < 0.05) for rats treated with 75 mg/kg+CP, 225 mg/kg+CP and 225 mg/kg.

CONCLUSION

Findings from this study demonstrates that the hydro-ethanolic root extract of Z. zanthoxyloides could be beneficial in hyperlipidemia and in cases of malignancies with abnormal cholesterol metabolism an effect which may be mediated via combating oxidative stress. List of Abbreviations: EDTA: Ethylenediamine-tetra acetate; MDA: Malondialdehyde; PCV: Packed cell volume; RBC: Red blood cell; HGB: Hemoglobin; WBC: White blood cell; ALT: Alanine transaminase; AST: Aspartate transaminase; CHOL: Cholesterol; LDL: Low density lipoprotein; HDL: High density lipoprotein; GSH: Reduced glutathione; SOD: Superoxide dismutase; CAT: Catalase; CP: Cyclophosphamide.

Synthesis of novel coumarin appended bis(formylpyrazole) derivatives: Studies on their antimicrobial and antioxidant activities

A series of novel coumarin pyrazole hybrids of biological interest were synthesized from the hydrazones, carbazones and thiocarbazones via Vilsmeier Haack formylation reaction. These intermediates and formyl pyrazoles were evaluated for antimicrobial and antioxidant activities. Among the series, compounds 6g and 6h showed excellent antimicrobial activity against different bacterial and fungal strains and compounds 7g, 7h were found to be potent antioxidant agents in both DPPH and hydroxyl radical scavenging assays. Further, detailed quantitative structure-activity relationship (QSAR) analysis indicated the molecular parameters that contribute to increased potency of inhibition. The above findings would further encourage our understanding in employing coumarin pyrazole hybrids as potential antibiotic agents for treating infections caused by pathogenic microbes and fungi. Further, it also paves the way for exploration of these compounds as potential therapeutic agents to treat conditions arising because of excessive oxidative damage.

Biological Activities of Tetrodotoxin-Producing Enterococcus faecium AD1 Isolated from Puffer Fishes

Puffer fishes were collected from the central sea in Vietnam from spring to summer season. The eggs were incubated in MRS broth that was used to test the toxicity in mice and isolate the lactic acid bacteria community that could produce tetrodotoxin (TTX). Thin layer chromatography (TLC) and high performance lipid chromatography (HPLC) were used to detect and quantify TTX. As a result, Enterococcus faecium AD1 which was identified by biochemical test and 16S rRNA analysis could produce TTX 0.3 mg/mL when cultured in MRS broth. The bacterium was optimized for TTX production and gave 0.18 mg/mL, 0.07 mg/mL, and 0.15 mg/mL in media prepared from the meat-washing water of freshwater fishes (Pangasius bocourti, Oreochromis sp.) and sea fish (Auxis thazard), respectively, that are also hopeful to answer some poisoning cases related to eating fishes. Enterococcus faecium also showed the wide antimicrobial activities on yeast, Gram-negative and -positive bacteria. Extracted exopolysaccharide (EPS) that reacted with 2,2-diphenyl-1-picrylhydrazyl to give IC₅₀ at 5 mg/mL equaled 11 mg/mL ascorbic acid which could show effects on Hela-6 and Hep G2 using sulforhodamine B test. Enterococcus faecium can be claimed as a promising source in tetrodotoxin and biological compounds.

Investigation of the Anti-Melanogenic and Antioxidant Characteristics of Eucalyptus camaldulensis Flower Essential Oil and Determination of Its Chemical Composition

The effects of essential oil from Eucalyptus camaldulensis flowers oil on melanogenesis and the oil’s antioxidant characteristics were investigated. Assays of mushroom and cellular tyrosinase activities and melanin content of mouse melanoma cells were performed spectrophotometrically, and the expression of melanogenesis-related proteins was determined by Western blotting. The possible signaling pathways involved in essential oil-mediated depigmentation were also investigated using specific protein kinase inhibitors. The results revealed that E. camaldulensis flower essential oil effectively suppresses intracellular tyrosinase activity and decreases melanin amount in B16F10 mouse melanoma cells. The essential oil also exhibits antioxidant properties and effectively decreases intracellular reactive oxygen species (ROS) levels. The volatile chemical composition of the essential oil was analyzed with gas chromatography–mass spectrometry (GC/MS). The chemical constituents in the essential oil are predominately oxygenated monoterpenes (34.9%), followed by oxygenated sesquiterpenes (31.8%), monoterpene hydrocarbons (29.0%) and sesquiterpene hydrocarbons (4.3%). Our results indicated that E. camaldulensis flower essential oil inhibits melanogenesis through its antioxidant properties and by down-regulating both mitogen-activated protein kinases (MAPK) and protein kinase A (PKA) signaling pathways. The present study indicates that the essential oil has the potential to be developed into a skin care product.

Essential Role of Calmodulin in RyR Inhibition by Dantrolene

Dantrolene is the first line therapy of malignant hyperthermia. Animal studies suggest that dantrolene also protects against heart failure and arrhythmias caused by spontaneous Ca(2+) release. Although dantrolene inhibits Ca(2+) release from the sarcoplasmic reticulum of skeletal and cardiac muscle preparations, its mechanism of action has remained controversial, because dantrolene does not inhibit single ryanodine receptor (RyR) Ca(2+) release channels in lipid bilayers. Here we test the hypothesis that calmodulin (CaM), a physiologic RyR binding partner that is lost during incorporation into lipid bilayers, is required for dantrolene inhibition of RyR channels. In single channel recordings (100 nM cytoplasmic [Ca(2+)] + 2 mM ATP), dantrolene caused inhibition of RyR1 (rabbit skeletal muscle) and RyR2 (sheep) with a maximal inhibition of Po (Emax) to 52 ± 4% of control only after adding physiologic [CaM] = 100 nM. Dantrolene inhibited RyR2 with an IC50 of 0.16 ± 0.03 µM. Mutant N98S-CaM facilitated dantrolene inhibition with an IC50 = 5.9 ± 0.3 nM. In mouse cardiomyocytes, dantrolene had no effect on cardiac Ca(2+) release in the absence of CaM, but reduced Ca(2+) wave frequency (IC50 = 0.42 ± 0.18 µM, Emax = 47 ± 4%) and amplitude (IC50 = 0.19 ± 0.04 µM, Emax = 66 ± 4%) in the presence of 100 nM CaM. We conclude that CaM is essential for dantrolene inhibition of RyR1 and RyR2. Its absence explains why dantrolene inhibition of single RyR channels has not been previously observed.