Phenolic compounds and antioxidants from Eucalyptus camaldulensis as affected by some extraction conditions,a preparative optimization for GC-MS analysis

Abstract

Four organic solvents along with water were applied for the conventional extraction of Eucalyptus camaldulensis (Myrtaceae), phenolic contents and antioxidant activities were investigated through variable protocols and correlation coefficients were considered, the phenolic composition was also characterized by Gas chromatography-mass spectrometry (GC-MS). Using solvents with dissimilar polarities affected the phenolic yields extracted from E. camaldulensis and their related antioxidant activities varied significantly among the four investigated plant organs. The leaf extract of acetone 70% contained the highest amount of phenolic compounds (46.56?mg/g dry weight); while the bud-water boiled extract maintained the maximum value of tannins (45.68?mg/g dry weight). Correlation coefficients indicated that phenolic compounds were mostly accountable for the phosphomolybednum antioxidant potentials (0.520), followed by tannins (0.460). Also, both the reducing power activities and hydrogen peroxide scavenging of E. camaldulensis extracts positively correlated with tannins, but at different significance degrees. However, the GC-MS analysis revealed that most of the detected phenolic constituents were more abundant in the plant seed. So, the existence of some other compounds such as organic acids, along with phenolics, may have increased the antioxidant potentials of leaf and bud. Undeniably, the optimization of extraction conditions could stimulate the antioxidant capabilities of the plant extracts of E. camaldulensis.     

Effect of Pulsed Electromagnetic Fields on Human Mesenchymal Stem Cells Using 3D Magnetic Scaffolds

Alternative bone regeneration strategies that do not rely on harvested tissue or exogenous growth factors are needed. One of the major challenges in tissue reconstruction is recreating the bone tissue microenvironment using the appropriate combination of cells, scaffold, and stimulation to direct differentiation. This study presents a bone regeneration formulation that involves the use of human adipose-derived mesenchymal stem cells (hASCs) and a three-dimensional (3D) hydrogel scaffold based on self-assembled RADA16 peptides containing superparamagnetic iron oxide nanoparticles (NPs). Although superparamagnetic NPs could be used as stimulus to manipulate the cell proliferation and differentiation, in this paper their use is explored for assisting osteogenic differentiation of hASCs in conjunction with direct stimulation by extremely low-frequency pulsed electromagnetic fields (pEMFs). Cellular morphology, proliferation, and viability, as well as alkaline phosphatase activity, calcium deposition, and osteogenic capacity were monitored for cells cultured up to 21 days in the 3D construct. The results show that the pEMFs and NPs do not have any negative effect on cell viability, but instead distinctly induced early differentiation of hASCs to an osteoblastic phenotype, when compared with cells without biophysical stimulation. This effect is attributed to synergy between the pEMFs and NPs, which may have stimulated mechanotransduction pathways, which, in turn activated biochemical signals between cells to differentiate or proliferate. This approach may offer a safe and effective option for the treatment of non-union bone fractures. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.     

A Comparative Study of Excitatory and Inhibitory Amino Acids in Three Different Brainstem Nuclei

This study was designed to shed more light onto the three different brainstem regions which are implicated in the pain pathway for the level of various excitatory and inhibitory neurotransmitters before and following neuronal stimulation. The in vivo microdialysis technique was used in awake, freely moving adult Sprague-Dawley rats. The neurotransmitters studied included aspartate, glutamate, GABA, glycine, and taurine. The three brainstem regions examined included the mid-brain periaqueductal gray (PAG), the medullary nucleus raphe magnus (NRM), and the spinal trigeminal nucleus (STN). Neuronal stimulation was achieved following the administration of the sodium channel activator veratridine. The highest baseline levels of glutamate (P < 0.0001), aspartate (P < 0.0001), GABA (P < 0.01), taurine (P < 0.0001), and glycine (P < 0.001) were seen in the NRM. On the other hand, the lowest baseline levels of glutamate, GABA, glycine, and taurine were found in the PAG, while that of aspartate was found in the STN. Following the administration of veratridine, the highest release of the above neurotransmitters except for the aspartate and glycine was found in the PAG where the level of glutamate increased by 1,310 ± 293% (P < 0.001), taurine by 1,008 ± 143% (P < 0.01), and GABA by 10,358 ± 1,920% (P < 0.0001) when comparison was performed among the three brainstem regions and in relation to the baseline levels. The highest release of aspartate was seen in the STN (2,357 ± 1,060%, P < 0.001), while no significant difference was associated with glycine. On the other hand, the lowest release of GABA and taurine was found in the STN (696 ± 91 and 305 ± 25%, respectively), and glutamate and aspartate in the NRM (558 ± 200 and 874 ± 315%, respectively). Our results indicate, and for the first time, that although some differences are seen in the baseline levels of the above neurotransmitters in the three regions studied, there are quite striking variations in the level of release of these neurotransmitters following neuronal stimulation in these regions. In our opinion this is the first study to describe the pain activation/modulation related changes of the excitatory and inhibitory amino acids profile of the three different brainstem areas.     

Miltefosine Lipid Nanocapsules for Single Dose Oral Treatment of Schistosomiasis Mansoni: A Preclinical Study

Miltefosine (MFS) is an alkylphosphocholine used for the local treatment of cutaneous metastases of breast cancer and oral therapy of visceral leishmaniasis. Recently, the drug was reported in in vitro and preclinical studies to exert significant activity against different developmental stages of schistosomiasis mansoni, a widespread chronic neglected tropical disease (NTD). This justified MFS repurposing as a potential antischistosomal drug. However, five consecutive daily 20 mg/kg doses were needed for the treatment of schistosomiasis mansoni in mice. The present study aims at enhancing MFS efficacy to allow for a single 20mg/kg oral dose therapy using a nanotechnological approach based on lipid nanocapsules (LNCs) as oral nanovectors. MFS was incorporated in LNCs both as membrane-active structural alkylphospholipid component and active antischistosomal agent. MFS-LNC formulations showed high entrapment efficiency (EE%), good colloidal properties, sustained release pattern and physical stability. Further, LNCs generally decreased MFS-induced erythrocyte hemolytic activity used as surrogate indicator of membrane activity. While MFS-free LNCs exerted no antischistosomal effect, statistically significant enhancement was observed with all MFS-LNC formulations. A maximum effect was achieved with MFS-LNCs incorporating CTAB as positive charge imparting agent or oleic acid as membrane permeabilizer. Reduction of worm load, ameliorated liver pathology and extensive damage of the worm tegument provided evidence for formulation-related efficacy enhancement. Non-compartmental analysis of pharmacokinetic data obtained in rats indicated independence of antischistosomal activity on systemic drug exposure, suggesting possible gut uptake of the stable LNCs and targeting of the fluke tegument which was verified by SEM. The study findings put forward MFS-LNCs as unique oral nanovectors combining the bioactivity of MFS and biopharmaceutical advantages of LNCs, allowing targeting via the oral route. From a clinical point of view, data suggest MFS-LNCs as a potential single dose oral nanomedicine for enhanced therapy of schistosomiasis mansoni and possibly other diseases.     

Entrapment efficiency of pyridoxine hydrochloride in unilamellar liposomes: experimental versus model-generated data

The present study investigates the effect of the preparation method (four methods) and formulation additives (propylene glycol (PG) and cholesterol (CH)) on the entrapment efficiency (EE) of pyridoxine hydrochloride (vitamin B6 (VB6)), representing hydrophilic water-soluble low permeable vitamins, in unilamellar liposomes. The main aim is to compare determined EE with predicted values generated using a web-published, computational model. Results showed that among the different preparation methods, modified film hydration showed significantly higher EE (p?). With regard to formulation additives, PG (5% w/v) produced smaller vesicles size with narrow size distribution. Agreement between determined and model-generated EE values was more evident in formulae with narrow size distribution (polydispersity index (PdI) below 0.23). Formulae containing PG showed slightly higher determined than predicted EE values indicating vitamin–phospholipid bilayer interaction. Meanwhile, agreement between determined and predicted EE was limited to VB6-to-phospholipid ratio below (1.2:2). The comparison provided further insight into the usefulness of the prediction model factors affecting agreement between determined and predicted EE data.     

The association between overweight/obesity and psychological distress: A population based cross-sectional study in Saudi Arabia

ObjectivesThe objective of this study was to compare the association between mental well-being between obese (classes 1 and 2), over-weight and non-obese population-based individualsMethodsA population-based cross-sectional study was conducted in Al-Kharj, Saudi Arabia. A total of 1019 Saudi nationals aged ≥ 18 years participated in the survey. BMI scores were used to categorize participants into three groups: Obese, overweighted and non-obese/non-overweight. Mental well-being was evaluated by using the validated Arabic version of the General Health Questionnaire version 12 (GHQ-12).ResultsWe used total GHQ score (Mean=12; SD=5.23) to compare mental well-being between the four BMI class categories. The overall one-way ANOVA model was statistically significant (F = 7.018, d = 6, P < 0.001). In multivariate analysis, after adjusting for sociodemographic variables, diabetes and smoking statuses we found that higher psychological distress (as evident by a higher total GHQ score) was associated with higher BMI. The unstandardized Beta regression coefficient = 2.627; P = 0.034). Females were more likely to have higher psychological distress than males (unstandardized Beta = 1.466, P = 0.003). Job status whether being unemployed or ‘civilian’ (civil worker) was significantly associated with higher psychological distress (unstandardized Beta = 1.405, P = 0.041). Being diabetic has a 1.6 times higher risk of psychological distress (unstandardized Beta = 1.604, P = 0.027).ConclusionThe study highlights the public health implications of psychological distress amongst individuals with overweight and obesity in Saudi Arabia. Future longitudinal studies should explore the temporality of this relationship.     

Regulation of in vitro bud formation of date palm (Phoenix dactylifera L.) cv. Khanezi by different carbon sources

The influence of different carbon sources and concentrations on in vitro shoot multiplication of date palm cv. Khanezi were investigated. Sucrose, glucose, fructose and maltose sugars were used at the following concentrations; 0, 30, 60, 90 and 120 g l(-1). Shoot dry weight was significantly increased with increasing sugar concentrations while little growth was obtained in the absence of sugar. Concentrations of 30 and 60 g l(-1) were optimal for qualitative and quantitative shoot growth while abnormal growth was observed at 90 and 120 g l(-1) possibly due to osmotic stress. Sugar type had significant effects on most parameters measured except bud formation. Fructose produced the highest values of dry weights compared with other carbon sources. In addition, glucose, fructose and maltose were almost equivalently effective as a carbon source for culture of date palm compared with sucrose. It is also noticed in this study that the root formation was enhanced as the sugar concentration increased (60 g l(-1) and above). This rooting of buds generally reduced their ability to multiply during multiplication stage and occasionally inhibited bud formation especially in higher concentration of sugar.     

Identification and sequencing of Date-SRY Gene: A novel tool for sex determination of date palm (Phoenix dactylifera L.)

Dioecism has always been an issue in many plant species with its numerous disadvantages, especially in woody trees such as date palms. As one of the most important crops in the Middle Eastern countries, researchers are having problems identifying of sex of the plant in its early stages of development. Hence, proper population stands in the male: female ratio for maintenance is almost impossible in the field for better production. In this study, sex determination of date palm (Phoenix dactilyfera L.) were identified in regions of the Y chromosome (Date-SRY) gene, the pivotal gene that initiates sex determination, using a new technique and thus an economically desirable objective, which will significantly impact profits in seed based cultivations. Partial sequences of the Date-SRY were taken and amplified by nested polymerase chain reaction (PCR). According to the results, the exact sex of date palm was identified in all the tested plants, while amplified regions of the Date-SRY gene closely matched with the human and papaya sequences. In addition, a primer pair was designed to amplify the sequences of the SRY-date gene with confidence that it will identify male date palms. These primer sequences include SRY-date Forward 5′- cggccctctaagtatctgtgcgcaacg-3′ (SRY-date F) and the SRY-date Reverse 5′- gtttgcacttcgaagcagag-3′ (SRY-date R). The complete sequence of the DNA has been registered and deposited in GenBank (BankIt1598036 DPSRY1 KC577225 thenKJ873056).     

Induction of β-family chemokines mRNA in human embryonic astrocytes by inflammatory cytokines

The cellular infiltration found during CNS inflammation consists of monocytes and activated T cells, suggesting the presence of cell-specific chemotactic signals during inflammatory responses. Astrocyte chemokine expression might contribute to site-specific leukocyte infiltration within the CNS. To investigate the factors that regulate astrocyte chemokine expression, we examined the ability of human fetal astrocytes to induce β-family chemokine mRNA. Astrocyte-derived monocyte chemoattractant protein-1 (MCP-1), RANTES, macrophage inflammatory protein-1α (MIP-1α), and MIP-1β mRNA were easily induced by lipopolysaccharide and/or the proinflammatory cytokines (IFNγ and/or TNF-α), respectively. Addition of both IFNγ and TNF-α together did not lead to an additive effect but resulted in the inhibition of MCP-1 and MIP-1β mRNA expression, indicating that interaction between chemokines and cytokines may play a key role in regulating the local immune response of resident and infiltrating cells at the site of lesion. Interestingly, ultraviolet light-inactivated measles virus, but not cytomegalovirus, strongly induced expression of MCP-1, RANTES, MIP-1α, and MIP-1β mRNA in human embryonic astrocytes, especially MCP-1 and MIP-1β. An association occurs between the β-family chemokine expression in astrocytes and inflammatory factors/virus, suggesting a possible role for β-family chemokines in the pathogenesis of CNS inflammatory disease.