From Aloe vera Leaf Waste to the Extracts with Biological Potential: Optimization of the Extractions, Physicochemical Characterization, and Biological Activities

In the study, the optimization of the extraction from Aloe vera leaf waste was performed via varying solid-to-solvent ratio, solvent type, extraction time, and technique (maceration, heat-, ultrasound-, and microwave-assisted extractions—HAE, UAE, and MAE, respectively). The optimal extraction conditions for achieving the highest polyphenol content are a 1:30 ratio, 70% ethanol, and 30 min of HAE. Total flavonoid and protein contents were significantly higher in the extract from MAE, while total condensed tannin content was the highest in HAE. LC-MS analysis quantified 13 anthraquinone and chromone compounds. The variations in the FT-IR spectra of the extracts obtained by different extraction procedures are minor. The influence of extraction conditions on the antioxidant ability of the extracts depended on applied antioxidant assays. The extracts possessed medium inhibition properties against Staphylococcus aureus and weak inhibitory activity against Enterococcus feacalis. The extracts had stimulative effect on HaCaT cell viability. Regarding the extraction yield, there was a significant difference between the used extraction techniques (MAE > HAE > maceration and UAE). The presented study is an initial step in the production of polyphenol-rich extracts from A. vera leaf waste aimed to be used for the potential preparation of pharmaceutical and cosmetic formulations for the skin

Vaccinium myrtillus L. Leaf Waste as a Source of Biologically Potent Compounds: Optimization of Polyphenol Extractions, Chemical Profile, and Biological Properties of the Extracts

The aims of the present research include (1) optimization of extraction from Vaccinium myrtillus leaf waste via investigation of plant material:medium ratio, extraction medium, and extraction period, employing extractions at room and high temperatures, or using ultrasound and microwaves (M, HAE, UAE, and MAE, respectively), (2) physicochemical characterization, and (3) investigation of extract biological potential. The statistical analysis revealed that optimal levels of parameters for the greatest polyphenolic yield were a proportion of 1:30 g/mL, ethyl alcohol 50% (v/v) during 2 min of microwave irradiation. By LC-MS analysis, 29 phenolic components were detected; HAE showed the highest richness of almost all determined polyphenols, while chlorogenic acid and quercetin 3-O-glucuronide were dominant. All extracts showed a high inhibition of Staphylococcus aureus growth. The effect of different parameters on extracts’ antioxidant capacity depended on the used tests. The extracts also showed a stimulative influence on keratinocyte viability and anti-inflammatory activity (proven in cell-based ELISA and erythrocyte stabilization assays). The extraction procedure significantly affected the extraction yield (MAE ≥ maceration ≥ UAE ≥ HAE), whereas conductivity, density, surface tension, and viscosity varied in a narrow range. The presented research provides evidence on the optimal extraction conditions and technique, chemical composition, and antioxidant, antimicrobial, anti-inflammatory, and keratinocyte viability properties of bilberry extracts for potential applications in pharmacy and cosmetics

Toxicity of Silver Nanoparticles Supported by Surface-Modified Zirconium Dioxide with Dihydroquercetin

The antibacterial performance and cytotoxic examination of in situ prepared silver nanoparticles (Ag NPs), on inorganic-organic hybrid nanopowder consisting of zirconium dioxide nanoparticles (ZrO2 NPs) and dihydroquercetin (DHQ), was performed against Gram (−) bacteria Escherichia coli and Gram (+) bacteria Staphylococcus aureus, as well as against human cervical cancer cells HeLa and healthy MRC-5 human cells. The surface modification of ZrO2 NPs, synthesized by the sol-gel method, with DHQ leads to the interfacial charge transfer (ICT) complex formation indicated by the appearance of absorption in the visible spectral range. The prepared samples were thoroughly characterized (TEM, XRD, reflection spectroscopy), and, in addition, the spectroscopic observations are supported by the density functional theory (DFT) calculations using a cluster model. The concentration- and time-dependent antibacterial tests indicated a complete reduction of bacterial species, E. coli and S. aureus, for all investigated concentrations of silver (0.10, 0.25, and 0.50 mg/mL) after 24 h of contact. On the other side, the functionalized ZrO2 NPs with DHQ, before and after deposition of Ag NPs, do not display a significant decrease in the viability of HeLa MRC-5 cells in any of the used concentrations compared to the contro

Oleuropein Attenuates Oxidative Stress in Human Trophoblast Cells

Olive-derived bioactive compound oleuropein was evaluated against damage induced by hydrogen peroxide in human trophoblast cells in vitro, by examining the changes in several markers implicated in oxidative stress interactions in the placenta. Trophoblast HTR-8/SVneo cells were preincubated with OLE at 10 and 100 µM and exposed to H2O2, as a model of oxidative stress. Protein and lipid peroxidation, as well as antioxidant enzymes’ activity, were determined spectrophotometrically, and DNA damage was evaluated by comet assay. iNOS protein expression was assessed by Western blot, while the mRNA expression of pro- and anti-apoptotic genes BAX and BCL2 and transcription factor NFE2L2, as well as cytokines IL-6 and TNF α were determined by qPCR. Oleuropein demonstrated cytoprotective effects against H2O2 in trophoblast cells by significantly improving the antioxidant status and preventing protein and lipid damage, as well as reducing the iNOS levels. OLE reduced the mRNA expression of IL-6 and TNF α, however, it did not influence the expression of NFE2L2 or the BAX/BCL2 ratio after H2O2 exposure. Oleuropein per se did not lead to any adverse effects in HTR-8/SVneo cells under the described conditions, confirming its safety in vitro. In conclusion, it significantly attenuated oxidative damage and restored antioxidant functioning, confirming its protective role in trophoblast. © 2023 by the authors

Pumpkin pulp extracts from a Serbian Cucurbita maxima Breeding Collection: Phenol profile and in vitro bioactivity

Methanolic pulp extracts from the four selected Serbian accessions of Cucurbita maxima were evaluated for phenol profile cytotoxic effects and antimicrobial activity. The results revealed that quinic acid and amentoflavone were the most abundant phenols. The extracts increased the viability of HTR-8 SV/Neo, JEG-3, JAR cells, with the most pronounced increase in the treatment with MAX 113 extract. Furthermore, in HeLa cells, the extracts showed a modest cytotoxic effect. The antimicrobial effects evaluation showed that out of four pumpkin extracts, MAX 117 could moderately suppress the growth of Staphylococcus aureus and Staphylococcus epidermidis (MIC=1000 µg/mL). The observed biological effects indicate the potential medicinal properties of these pumpkin extracts and contribute to the varietal selection of the most suitable accessions in national breeding programs as candidates for improving human health

IL-6 and IL-8: An Overview of Their Roles in Healthy and Pathological Pregnancies

Interleukin-6 (IL-6) is an acknowledged inflammatory cytokine with a pleiotropic action, mediating innate and adaptive immunity and multiple physiological processes, including protective and regenerative ones. IL-8 is a pro-inflammatory CXC chemokine with a primary function in attracting and activating neutrophils, but also implicated in a variety of other cellular processes. These two ILs are abundantly expressed at the feto-maternal interface over the course of a pregnancy and have been shown to participate in numerous pregnancy-related events. In this review, we summarize the literature data regarding their role in healthy and pathological pregnancies. The general information related to IL-6 and IL-8 functions is followed by an overview of their overall expression in cycling endometrium and at the feto-maternal interface. Further, we provide an overview of their involvement in pregnancy establishment and parturition. Finally, the implication of IL-6 and IL-8 in pregnancy-associated pathological conditions, such as pregnancy loss, preeclampsia, gestational diabetes mellitus and infection/inflammation is discussed

Antioxidative and anti-inflammatory effects of taxifolin in H2O2-induced oxidative stress in HTR-8/SVneo trophoblast cell line

Oxidative stress has been implicated in numerous pregnancy-related disorders. Biologically active plant secondary metabolites, which are present in everyday diet, could prove effective therapeutic agents in preventing these disorders. This study evaluated effects of taxifolin (dihydroquercetin) on ROS production, markers of oxidative damage to lipids and proteins, activity of antioxidant enzymes and production of pro-inflammatory cytokines in H2O2-induced oxidative stress in trophoblast HTR-8/SVneo cells. Taxifolin in 10 µM and 100 µM concentrations attenuated oxidative damage to lipids and proteins, as evidenced by a decrease in MDA content, extracellular LDH activity, carbonyl groups and nitrite contents. A reduction in the activity of antioxidant enzymes SOD, CAT and GPx in cells pre-treated with taxifolin, prior to H2O2 exposure, was also observed, along with a reduction in intracellular ROS production. Both evaluated concentrations of taxifolin showed antiinflammatory activity in trophoblast cells, by reducing production of pro-inflammatory cytokines IL-1β and IL6. In this model of H2O2-induced oxidative stress, taxifolin showed marked antioxidative and antiinflammatory activities in trophoblast cells, adding further evidence of its protective effects and showing potential as a therapeutic agent in preventing adverse pregnancy outcomes

Spectroscopic signature of ZnO NP-induced cell death modalities assessed by non-negative PCA

Selective cytotoxicity of ZnO nanoparticles among different cell types and cancer and non-cancerous cells has been demonstrated earlier. In the view of anticancer potential of ZnO nanoparticles and their presence in numerous industrial products, it is of great importance to carefully evaluate their effects and mechanisms of action in both cancerous and healthy cells. In this paper, the effects of ZnO nanoparticles on cancerous HeLa and non-cancerous MRC-5 cells are investigated by studying the changes in the vibrational properties of the cells using Raman spectroscopy. Both types of cells were incubated with ZnO nanoparticles of average size 40 nm in the doses from the range 10–40 µg/ml for the period of 48 h, after which Raman spectra were collected. Raman modes’ intensity ratios I1659/I1444, I2855/I2933 and I1337/I1305 were determined as spectral markers of the cytotoxic effect of ZnO in both cell types. Non-negative principal component analysis was used instead of standard one for analysis and detection of spectral features characteristic for nanoparticle-treated cells. The first several non-negative loading vectors obtained in this analysis coincided remarkably well with the Raman spectra of particular biomolecules, showing increase of lipid and decrease of nucleic acids and protein content. Our study pointed out that Raman spectral markers of lipid unsaturation, especially I1270/I1300, are relevant for tracing the cytotoxic effect of ZnO nanoparticles on both cancerous and non-cancerous cells. The change of these spectral markers is correlated to the dose of applied nanoparticles and to the degree of cellular damage. Furthermore, great similarity of spectral features of increasing lipids to spectral features of phosphatidylserine, one of the main apoptotic markers, was recognized in treated cells. Finally, the results strongly indicated that the degree of lipid saturation, presented in the cells, plays an important role in the interaction of cells with nanoparticles

The Role of Dietary Polyphenols in Pregnancy and Pregnancy-Related Disorders

Polyphenols are a group of phytochemicals with extensive biological functions and health-promoting potential. These compounds are present in most foods of plant origin and their increased widespread availability through the intake of nutritional supplements, fortified foods, and beverages, has also led to increased exposure throughout gestation. In this narrative review, we focus on the role of polyphenols in both healthy and pathological pregnancy. General information related to their classification and function is followed by an overview of their known effects in early-pregnancy events, including the current insights into molecular mechanisms involved. Further, we provide an overview of their involvement in some of the most common pregnancy-associated pathological conditions, such as preeclampsia and gestational diabetes mellitus. Additionally, we also discuss the estimated possible risk of polyphenol consumption on pregnancy outcomes. The consumption of dietary polyphenols during pregnancy needs particular attention considering the possible effects of polyphenols on the mechanisms involved in maternal adaptation and fetal development. Further studies are strongly needed to unravel the in vivo effects of polyphenol metabolites during pregnancy, as well as their role on advanced maternal age, prenatal nutrition, and metabolic risk of the offspring

Galectins in Early Pregnancy and Pregnancy-Associated Pathologies

Galectins are a family of conserved soluble proteins defined by an affinity for β-galactoside structures present on various glycoconjugates. Over the past few decades, galectins have been recognized as important factors for successful implantation and maintenance of pregnancy. An increasing number of studies have demonstrated their involvement in trophoblast cell function and placental development. In addition, several lines of evidence suggest their important roles in feto-maternal immune tolerance regulation and angiogenesis. Changed or dysregulated galectin expression is also described in pregnancy-related disorders. Although the data regarding galectins’ clinical relevance are still at an early stage, evidence suggests that some galectin family members are promising candidates for better understanding pregnancy-related pathologies, as well as predicting biomarkers. In this review, we aim to summarize current knowledge of galectins in early pregnancy as well as in pregnancy-related pathologies