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  • Open access
  • 128 Reads
Assessment of the role of protein transporters in drug toxicity studies.

According to the research of International Union of Primary and Clinical Pharmacology and the British Pharmacological Society, ion channels are the third-largest target group for drugs. They participate in controlling physiological and pathological processes in the body. Voltage Gated Ion Channels (VGICs) take part in generating and transmitting information within the cells of the central and peripheral nervous and cardiovascular systems.

Statistically, one of the most common reasons for drug withdrawal is the risk of cardiotoxicity, so drug safety guidelines are constantly being tightened. Many heart diseases result from disruption of the normal function of ion channels, so a thorough investigation of their role and function in the cardiovascular system is essential. In the recently proposed changes to the cardiovascular safety assessment paradigm by indicating the need to assess drug interactions with cardiac VGIC (such as: KV11.1, NaV1.5, and CaV1.2) and their impact on the electrophysiology of human ventricular cells.

This paper presents the latest guidelines on the safety of cardiac drugs. Three ion channels, KV11.1, NaV1.5, and CaV1.2, were assessed as potential targets for cardiac disrupting drugs. New advanced compound toxicity testing guidelines require specialized knowledge and tools, that quickly and reliably provide information about the test drug. Therefore, a methodology is presented for the use of in silico techniques, in the process of compound toxicity testing.

  • Open access
  • 246 Reads
Acute and chronic effects of medium-chain triglyceride supplementation on metabolic parameters and working memory in rats


Medium-chain triglycerides (MCT) have demonstrated a wide range of neuroprotective effects, although the mechanisms still remain poorly understood. Animal models are indispensable for such research. Metabolic effects of regular diet supplementation with fats must be considered.


Male Wistar rats aged 2.5 months received (o/g) either MCT oil (C8 & C10, 3 g/kg), lard (3 g/kg), or water (control) as a supplement to standard chow for 28 days. On the 17th day, the animals were tested in Y-maze. On the 28th day, blood was collected for biochemical testing (glucose, triglycerides, total cholesterol, HDL cholesterol). In a separate experiment, animals received 3 g/kg MCT, or lard, or water, and were then sacrificed 30 or 120 min after. Blood was collected for biochemical testing (glucose, lactate, pyruvate, acetoacetate, β-hydroxybutyrate (BHB), cholesterol, triglycerides, aspartate transaminase, alanine transaminase (ALT)).

Results and Discussion.

In the Y-maze test, the MCT-fed rats demonstrated an increased frequency of spontaneous alterations compared to both the control and lard groups, indicating improved working memory. Chronic administration of neither fat affected the blood glucose, triglycerides, total cholesterol, HDL cholesterol. Acutely, MCT supplementation elevated blood BHB, while lard did not. Lard administration increased blood triglycerides, cholesterol, and ALT, while MCT did not.


Daily supplementation of standard feed with MCT led to mild intermittent ketosis and improved working memory in rats. Neither chronic nor acute MCT administration had any adverse effect on metabolic health markers. This animal model may be used to study the mechanisms of the cognitive-enhancing effects of MCT.

  • Open access
  • 88 Reads
Modulation of human neutrophils’ oxidative burst by hydroxylated 2-styrylchromones: the relevance of the catechol group

2-Styrylchromones (2-SC) are a group of oxygen-containing heterocyclic compounds, which are characterized by the attachment of a styryl group to the C-2 position of their chromone core. Over the years, several biological activities have been attributed to 2-SC, such as antioxidant, anti-inflammatory, antimicrobial, antiviral, and antitumor. 1,2 Nonetheless, there are no reports in the literature about the effect of 2-SC on human neutrophils’ oxidative burst.

Therefore, the present study aims to evaluate the modulation of human neutrophils’ oxidative burst by a panel of hydroxylated 2-SC, analysing the structure-activity relationships. For that purpose, freshly isolated neutrophils from human blood were stimulated with phorbol-12-myristate-13-acetate and a chemiluminescence method was applied to evaluate the oxidative burst, using luminol as probe. 3

Considering the OH substituents present on B-ring of 2-SC, the tested compounds can be divided into three groups: group 1, with a catechol group (C-3’ and C-4’); group 2, with an OH at C-4’ and group 3, without any substitution on B-ring. The 2-SC from group 1 were the most active, with IC50 values in the order of 1 µM. In conclusion, the catechol B-ring appears to play an important role in the modulation of human neutrophils’ oxidative burst by 2-SC.

References: 1. Gomes et al. DOI: 10.2174/138955710791112550; 2. Santos et al. DOI: 10.1002/ejoc.201700003; 3. Ribeiro et al. DOI: 10.1016/j.ejmech.2013.06.019

Acknowledgements: The work was supported by PT national funds (FCT/MCTES) through grant UIDB/50006/2020 (LAQV-REQUIMTE Associate Laboratory) and from the European Union (FEDER funds through COMPETE POCI-01-0145-FEDER-029253).

  • Open access
  • 263 Reads
Green synthesis, characterization, and bioactivity of silver-nanoparticles from algal polysaccharide of Chnoospara minima

The current study aimed to test the cytotoxic efficacy of silver nanoparticles (Ag-NPs) synthesized using polysaccharide from marine algae Chnoospora minima against Human Breast Cancer (MCF-7) Cells in vitro. The extracted polysaccharide and the synthesized Ag-NPs were analyzed by Fourier-transform infrared spectroscopy (FTIR). Biosynthesized silver nanoparticles (Ag-NPs) were characterized using UV-spectrophotometry, dynamic light scattering (DLS), Zeta Potential, Scanning electron microscopy (SEM), and Energy Dispersive X-ray (EDX). Cytotoxicity was assessed using the Sulforhodamine B assay (SRB assay). A dose-dependent cytotoxic effect with an IC50 value of 3.921 µgmL-1 was observed for biosynthesized Ag-NPs against MCF-7 compared to the control (IC50:>200 µgmL-1 ). An absorption peak at 420 nm in UV–vis spectrum proven the formation of Ag-NPs; DSL analysis confirmed the formed particles are within the nanoscale with a Z-Average of 84 d.nm and Zeta potential was -18.5 mV. The SEM imaging showed biosynthesized Ag-NPs have a spherical shape with low aggregation. The EDX spectrometers confirmed the presence of an elemental silver signal of the biosynthesized Ag-NPs. SRB assay demonstrated that the green synthesized Ag-NPs inhibit the proliferation of MCF-7 cells. The present study's innovation is that the green synthesis of NPs, which is cost-effective and straightforward, providing stable nano-materials, an alternate for the large-scale synthesis of silver nanoparticles.

  • Open access
  • 119 Reads
Blood compatibility of originally synthesized amphiphilic dendrons

Dendrons and dendrimers are nanoscale polymer molecules with unique hyperbranched structure. The high number of functional groups enable these polymers to be easily modified further, thus creating potential for use as therapeutics. Their interactions with biological systems are mainly predetermined by their chemical structure, terminal groups, surface charge and by the number of branched layers (i.e. generation). Blood compatibility is a mandatory requisite for the safe intravenous administration of drug-loaded nanoparticles. In this work, we assessed the interactions of originally synthesized amphiphilic phosphorous dendrons with whole human blood. We investigated changes in more than dozen hematological and some coagulation parameters upon addition of the first and second generation dendrons at the lower and upper limits of the concentration range (2-10 µM) examined in our previous experiments. We found significantly decreased number of platelets associated with a significant increase in the activated partial thromboplastin time for the combination of higher concentration and the 2nd generation dendron. Viewing blood films under the light microscope confirmed occasional platelets clumps in this experimental condition. Findings at other conditions were not associated with any clinical significance from a hematological point of view. Our data indicate that thrombogenic propensity might not be the only issue in the nanomedicine safety. Coagulation abnormalities may also relate to prolonged clotting time – presumably as a result of induced consumption of clotting factors and/or platelets. In vitro assays using human blood appear to be a suitable tool to study mechanisms of dendron-based nanomedicines interference with hemostasis and to optimize their hemocompatibility.

  • Open access
  • 119 Reads
Covalent Electrosprayed Nanoparticles Based on Protease Treated Arabinoxylans

Arabinoxylans (AX) are polysaccharides constituted by a linear chain of β-(1→4) xylose units and α-L-arabinose substitutions, which can be esterified to ferulic acid (FA). A small amount of protein is associated with the AX chains [1]. AX have the ability to form covalent gels via FA oxidative coupling [2]. AX gels are resistant to pH and temperature changes but fermented by colonic microbiota, being therefore attractive as controlled release systems for therapeutic agents directed to the colon [3]. The AX capability to form covalently cross-linked nanoparticles was recently reported [4]; however, that investigation did not consider the effect of protein content in this polysaccharide property. The present study aimed to evaluate the effect of AX protein partial remotion on the polysaccharide potential to form covalent electrosprayed nanoparticles. AX were partially deproteinized using protease (AX-PD), resulting in a decrease in protein content from 16.4±0.5 to 10.8±0.1 %. Fourier transform infrared spectrum of AX-PD showed a diminution in the amide I and II bands concerning AX. The elastic modulus of laccase-induced AX-DP gels (1% w/v) was higher (284±12 Pa) than the value registered for AX gels (222±5 Pa). Electrosprayed 1% (w/v) AX and AX-PD nanoparticles revealed a spherical morphology when analyzed by transmission electron microscopy. The nanoparticles size distribution ranged from 19 to 390 nm and from 30 to 330 nm for AX and AX-PD, respectively. These results indicate that AX protease treatment improves the polysaccharide capability to form covalent electrosprayed nanoparticles, which could be used for pharmaceutical and biomedical applications.


  1. Saulnier, L.; Guillon, F.; Sado, P.-E.; Chateigner-Boutin, A.-L.; Rouau, X. Plant Cell Wall Polysaccharides in Storage Organs: Xylans (Food Applications). In Reference Module in Chemistry, Molecular Sciences and Chemical Engineering; Elsevier, 2013; p. np ISBN 978-0-12-409547-2.
  2. Morales-Ortega, A.; Niño-Medina, G.; Carvajal-Millán, E.; Gardea-Béjar, A.; Torres-Chávez, P.; López-Franco, Y.; Rascón-Chu, A.; Lizardi-Mendoza, J. Los Arabinoxilanos Ferulados De Cereales. Una Revisión De Sus. Rev. Fitotec. Mex. 2013, 36, 439–446.
  3. Martínez-López, A.L.; Carvajal-Millan, E.; Sotelo-Cruz, N.; Micard, V.; Rascón-Chu, A.; López-Franco, Y.L.; Lizardi-Mendoza, J.; Canett-Romero, R. Enzymatically cross-linked arabinoxylan microspheres as oral insulin delivery system. Int. J. Biol. Macromol. 2019, 126, 952–959, doi:10.1016/j.ijbiomac.2018.12.192.
  4. De Anda-Flores, Y.; Carvajal-Millan, E.; Lizardi-Mendoza, J.; Rascon-Chu, A.; Martínez-López, A.L.; Marquez-Escalante, J.; Brown-Bojorquez, F.; Tanori-Cordova, J. Covalently cross-linked nanoparticles based on ferulated arabinoxylans recovered from a distiller’s dried grains byproduct. Processes 2020, 8, 691, doi:10.3390/PR8060691.
  • Open access
  • 78 Reads
Neuroprotective therapeutic strategy against neuronal damage

Currently, the methods of treating neurodegenerative diseases are not fully effective. The available drugs are not able to stop the disease process, but to slow it down, [1] therefore, research on new compounds and new approaches to treating these disorders is still ongoing. We are looking for compounds with neuroprotective properties that will prevent cell death as well as restore the function and number of damaged neurons [2].

The presented research focuses on developing an effective treatment of neurodegenerative diseases based on the compound with neuroprotective properties.

A multi-target antipsychotic compound, D2AAK1, was used in the conducted research. The experiments were carried out on mouse hippocampal neuron cells (HT-22), neuroblastoma cells (SH-SY5Y) and male Swiss mice. The conducted studies showed that the compound causes an increase in cell proliferation and improves memory in mice models. Moreover, the compound caused a reduction in the level of reactive oxygen species (ROS), nitrogen (RNS), a decrease in intracellular calcium levels (Ca2+) and the level of DNA damage in the form of micronuclei (MN).

Summarizing, the obtained preliminary results are promising for the future development of treatment for neurodegenerative diseases.

[1] F.J.E. Vajda, Neuroprotection and neurodegenerative disease, Journal of Clinical Neuroscience. 9 (2002) 4–8.

[2] M.C. Monteiro, M.D. Coleman, E.J. Hill, R.D. Prediger, C.S.F. Maia, Neuroprotection in Neurodegenerative Disease: From Basic Science to Clinical Applications, Oxid Med Cell Longev. 2017 (2017) 2949102.

  • Open access
  • 121 Reads
Hypolipidemic properties of cocoa and coffee by-products after simulated gastrointestinal digestion: A comparative approach.

New sustainable ingredients with beneficial properties for health are a main goal for the food industry. In this regard, cocoa shell (CS) and coffee pulp (CP), by-products from the coffee and cocoa industry produced worldwide in large amounts, are suitable candidates. We previously stated these by-products are sources of phytochemicals and dietary fiber with potential hypolipidemic properties. This study aimed to assess the hypolipidemic properties of CS and CP after simulated gastrointestinal digestion. The capacities of the residual fraction of each digestion phase to bind bile salts and cholesterol and inhibit the lipase activity were measured to establish the in vitro hypolipidemic properties of both by-products. Furthermore, the digested fractions effect on lipid accumulation was evaluated in HepG2 cell line. From results, the CS showed higher ability to bind cholesterol (4-24%) and salts (2-3%) in gastric and colonic phases. Meanwhile, during gastrointestinal phase, CP showed a greater capacity to bind cholesterol (1-13%) and bile salts (2%). The capacity to inhibit lipase activity was more accentuated in the CS in gastrointestinal digestion (16%) and in CP during gastric digestion (11%). Likewise, the digested fractions of both by-products (100 µg/mL) significantly alleviated the accumulation of fat (17-20%) in the HepG2 cell model after the stimulation of cells with palmitic acid. This comparative approach suggests that both by-products exhibit similar hypolipidemic properties after in vitro digestion. This study promotes the revalorization of cocoa and coffee by-products as novel ingredients with potential beneficial properties to prevent chronic metabolic diseases due to their remarkable hypolipidemic properties.

  • Open access
  • 86 Reads
Serologic APE1/Ref-1: New biomarker for Vascular Inflammation in Atherosclerosis.

Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is a secretable multifunctional protein. Since the concept of APE1/Ref-1 secretion was established in 2013, several studies have demonstrated the usefulness of APE1/Ref-1 as a serological biomarker. However, the role of APE1/Ref-1 in atherosclerotic vascular inflammation is unclear. Herein, we investigated the role of APE1/Ref-1 in atherosclerotic apolipoprotein E (ApoE-/-) mice fed with a Western-type diet as an animal model of vascular inflammation. We found that serologic APE1/Ref-1 was strongly correlated with vascular inflammation in these mice. Neutrophil/lymphocyte ratio, endothelial cell/macrophage activation, and atherosclerotic plaque formation, reflected by atherosclerotic inflammation, were increased in the ApoE-/- mice fed with a Western-type diet. Correlation analysis showed a high correlation between plasma APE1/Ref-1 levels and neutrophil/lymphocyte ratio, a marker of systemic inflammation. We conclude that APE1/Ref-1 expression is upregulated in aortic endothelial cells/macrophages of atherosclerotic mice, and that plasma APE1/Ref-1 levels could predict atherosclerotic inflammation, it is a useful biomarker for vascular inflammation in atherosclerosis.

  • Open access
  • 94 Reads
Significant Implications of Apolipoprotein A1 (APOA1) polymorphic sequence variation in bladder cancer with its relative expression predictive for differential bladder tumor grades

Background: Apolipoprotein A1 (APOA1) is a potential biomarker due its variable concentration in different types of cancers.

Objective: We for the first time evaluated the association between APOA1 -75 G/A, +83 C/T genotypes in tandem with APOA1 protein expression in urine samples to find out risk and potential relationship for differentially expressed urinary proteins and APOA1 genotypes.

Design: The study included 108 cases of bladder tumors and 150 healthy controls that were frequency matched to cases with respect to age, sex and smoking status. Genotyping was performed by PCR-RFLP and urinary expression of APOA1 protein was done by ELISA.

Results: Bladder tumor cases were significantly associated with APOA1-75 AA genotype (p<0.05) while as APOA1+83 CT heterozygotes showed association with cases (p<0.05). The overall distribution of different haplotypes showed a marked difference between cases and controls in GT when compared with wild type GC (p<0.03). Bladder tumor cases that carried variant genotype APOA1-75AA presented more (70.0%) with higher expression (≥20ng/ml) of APOA1 urinary protein and differed significantly against wild typeGG (p=0.03). Again, in low grade bladder tumors, urinary APOA1 protein significantly presented more (52.4% vs. 15.4% high grade) with higher expression (≥20ng) while high grade tumor cases (84.6% vs. 47.5% low grade) showed lower APOA1expression (<20ng/ml) (O.R= 6.08, p=0.002).

Conclusions: We found a strong association between APOA1-75G/A and risk for bladder tumor and its relation to urinary protein expression that substantiates its possible role as a marker for risk assessment of the disease and promising diagnostic marker for different grades of malignant bladder tumors

Key Words: Bladder cancer; APOA1; Genotype; Allele; Protein expression; Haplotype