Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (29,866)

Search Parameters:
Keywords = acidic proteins

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
23 pages, 3064 KiB  
Article
Immunohistochemical Analysis of Placental Tissue of Women Infected with SARS-CoV-2 During Pregnancy—A Prospective Clinical Study
by Marija Bicanin Ilic, Tamara Nikolic Turnic, Aleksandar Nikolov, Srdjan Mujkovic, Ivana Likic Ladjevic, Igor Ilic, Marija Spasojevic, Nikola Jovic, Jovana Joksimovic Jovic, Dejana Rakic, Begzudin Ahmetovic, Sara Rosic and Aleksandra Dimitrijevic
Int. J. Mol. Sci. 2025, 26(15), 7659; https://doi.org/10.3390/ijms26157659 (registering DOI) - 7 Aug 2025
Abstract
SARS-CoV-2 has an affinity for binding to the human Angiotensin-converting enzyme 2 (ACE2) receptor through cleavage and conformational changes at the S1–S2 boundary and the receptor binding domain of the spike protein, which is also the most variable part of SARS-CoV-2. This study [...] Read more.
SARS-CoV-2 has an affinity for binding to the human Angiotensin-converting enzyme 2 (ACE2) receptor through cleavage and conformational changes at the S1–S2 boundary and the receptor binding domain of the spike protein, which is also the most variable part of SARS-CoV-2. This study aimed to investigate the expression of Angiotensin-converting enzyme 2 (ACE2), spike protein, and CD68+ markers in placental tissue to demonstrate a possible correlation with the level of systemic oxidative stress biomarkers in patients who were infected with SARS-CoV-2 during pregnancy. A prospective clinical cohort study was designed to investigate the presence of CD68+ macrophages, ACE2, and spike proteins in placental tissue using immunohistochemical methods and to compare these results with oxidative stress from our previous study. Spike and CD68+ macrophages’ immunoreactivity were more pronounced in the placental tissue of patients from the SARS-CoV-2 group. Placental tissue spike protein and CD68+ immunoreactivity correlate with maternal and fetal Thiobarbituric Acid Reactive (TBARS) levels. This study has confirmed that spike protein expression in placental tissue is associated with the newborn’s stay in intensive neonatal care. Therefore, immunoreactivity analysis for the Spike antigen is important in detecting newborns at risk of early neonatal complications. Full article
(This article belongs to the Special Issue Molecular Insights into Placental Pathology)
Show Figures

Figure 1

17 pages, 4768 KiB  
Article
New Functional Food for the Treatment of Gastric Ulcer Based on Bioadhesive Microparticles Containing Sage Extract: Anti-Ulcerogenic, Anti-Helicobacter pylori, and H+/K+-ATPase-Inhibiting Activity Enhancement
by Yacine Nait Bachir, Ryma Nait Bachir, Meriem Medjkane, Nouara Boudjema and Roberta Foligni
Foods 2025, 14(15), 2757; https://doi.org/10.3390/foods14152757 (registering DOI) - 7 Aug 2025
Abstract
Salvia officinalis is an aromatic plant of Mediterranean origin traditionally used to treat inflammatory, cardiovascular, endocrine, and digestive diseases. In this work, the ability of the Salvia officinalis extract in the treatment of gastric ulcers was evaluated, and an innovative administration system was [...] Read more.
Salvia officinalis is an aromatic plant of Mediterranean origin traditionally used to treat inflammatory, cardiovascular, endocrine, and digestive diseases. In this work, the ability of the Salvia officinalis extract in the treatment of gastric ulcers was evaluated, and an innovative administration system was proposed to increase the therapeutic effect of this plant. Salvia officinalis ethanolic extract was prepared and analyzed by HPLC/UV-DAD and encapsulated in a matrix based on gelatin and pectin using an emulsion–coacervation process. The prepared microcapsules were analyzed by laser particle size, optical microscopy, in vitro dissolution kinetics, and ex vivo bioadhesion. In order to determine the action mechanism of Salvia officinalis extract, in the treatment of gastric ulcer, the in vivo anti-ulcerogenic activity in rats, using the ulcer model induced by ethanol; the in vivo anti-Helicobacter pylori activity; and in vitro inhibitory activity of H+/K+-ATPase were carried out. These three biological activities were evaluated for ethanolic extract and microcapsules to determine the effect of formulation on biological activities. Ethanolic extract of Salvia officinalis was mainly composed of polyphenols (chlorogenic acid 7.43%, rutin 21.74%, rosmarinic acid 5.88%, and quercitrin 14.39%). Microencapsulation of this extract allowed us to obtain microcapsules of 104.2 ± 7.5 µm in diameter, an encapsulation rate of 96.57 ± 3.05%, and adequate bioadhesion. The kinetics of in vitro dissolution of the extract increase significantly after its microencapsulation. Percentages of ulcer inhibition for 100 mg/kg of extract increase from 71.71 ± 2.43% to 89.67 ± 2.54% after microencapsulation. In vitro H+/K+-ATPase-inhibiting activity resulted in an IC50 of 86.08 ± 8.69 µM/h/mg protein for free extract and 57.43 ± 5.78 µM/h/mg protein for encapsulated extract. Anti-Helicobacter pylori activity showed a similar Minimum Inhibitory Concentration (MIC) of 50 µg/mL for the extract and microcapsules. Salvia officinalis ethanolic extract has a significant efficacy for the treatment of gastric ulcer; its mechanism of action is based on its gastroprotective effect, anti-Helicobacter pylori, and H+/K+-ATPase inhibitor. Moreover, the microencapsulation of this extract increases its gastroprotective and H+/K+-ATPase-inhibiting activities significantly. Full article
Show Figures

Figure 1

22 pages, 5700 KiB  
Article
Genome-Wide Identification and Expression Analysis of the GH19 Chitinase Gene Family in Sea Island Cotton
by Jingjing Ma, Yilei Long, Jincheng Fu, Nengshuang Shen, Le Wang, Shuaijun Wu, Jing Li, Quanjia Chen, Qianli Zu and Xiaojuan Deng
Curr. Issues Mol. Biol. 2025, 47(8), 633; https://doi.org/10.3390/cimb47080633 (registering DOI) - 7 Aug 2025
Abstract
In this study, GH19 chitinase (Chi) gene family was systematically identified and characterized using genomic assemblies from four cotton species: Gossypium barbadense, G. hirsutum, G. arboreum, and G. raimondii. A suite of analyses was performed, including genome-wide gene identification, [...] Read more.
In this study, GH19 chitinase (Chi) gene family was systematically identified and characterized using genomic assemblies from four cotton species: Gossypium barbadense, G. hirsutum, G. arboreum, and G. raimondii. A suite of analyses was performed, including genome-wide gene identification, physicochemical property characterization of the encoded proteins, subcellular localization prediction, phylogenetic reconstruction, chromosomal mapping, promoter cis-element analysis, and comprehensive expression profiling using transcriptomic data and qRT-PCR (including tissue-specific expression, hormone treatments, and Fusarium oxysporum infection assays). A total of 107 GH19 genes were identified across the four species (35 in G. barbadense, 37 in G. hirsutum, 19 in G. arboreum, and 16 in G. raimondii). The molecular weights of GH19 proteins ranged from 9.9 to 97.3 kDa, and they were predominantly predicted to localize to the extracellular space. Phylogenetic analysis revealed three well-conserved clades within this family. In tetraploid cotton, GH19 genes were unevenly distributed across 12 chromosomes, often clustering in certain regions, whereas in diploid species, they were confined to five chromosomes. Promoter analysis indicated that GH19 gene promoters contain numerous stress- and hormone-responsive motifs, including those for abscisic acid (ABA), ethylene (ET), and gibberellin (GA), as well as abundant light-responsive elements. The expression patterns of GH19 genes were largely tissue-specific; for instance, GbChi23 was predominantly expressed in the calyx, whereas GbChi19/21/22 were primarily expressed in the roots and stems. Overall, this study provides the first comprehensive genomic and functional characterization of the GH19 family in G. barbadense, laying a foundation for understanding its role in disease resistance mechanisms and aiding in the identification of candidate genes to enhance plant defense against biotic stress. Full article
13 pages, 1045 KiB  
Article
Antiviral Activity of Haematococcus pluvialis Algae Extract Is Not Exclusively Due to Astaxanthin
by Paula Peinsipp, Tanja Gerlza, Julia Kircher, Kurt Zatloukal, Corinna Jäger, Peter Pucher and Andreas J. Kungl
Pathogens 2025, 14(8), 791; https://doi.org/10.3390/pathogens14080791 (registering DOI) - 7 Aug 2025
Abstract
In this study, astaxanthin, which has previously been shown to have antiviral effects, was examined for its dose-dependent potency to inhibit cellular SARS-CoV-2 infections. Naturally occurring astaxanthin is obtained and orally administered as ASX-oleoresin, a composition of different astaxanthin fatty acid esters. We [...] Read more.
In this study, astaxanthin, which has previously been shown to have antiviral effects, was examined for its dose-dependent potency to inhibit cellular SARS-CoV-2 infections. Naturally occurring astaxanthin is obtained and orally administered as ASX-oleoresin, a composition of different astaxanthin fatty acid esters. We therefore hypothesized that the compound’s beneficial effects are not only related to astaxanthin. Thus, a “green” algae extract (i.e., poor astaxanthin content < 0.2%; ASXp) of the microalgae Haematococcus pluvialis, as well as an astaxanthin-rich algae extract (astaxanthin content = 20%; ASXr), were tested in in vitro cellular viral infection assays. Thereby, it was found that both extracts reduced viral infections significantly. As a potential mode of inhibitory action, the binding of ASX-oleoresin to the viral spike protein was investigated by isothermal fluorescence titration, revealing binding affinities of Kd = 1.05 µM for ASXr and Kd = 1.42 µM for ASXp. Based on our data, we conclude that several ASX-oleoresin fractions from H. pluvialis exhibit antiviral activity, which extends beyond the known antioxidant activity of astaxanthin. From a molecular dynamic simulation of ASX-oleoresin, fatty acid domains could be considered as activity-chaperoning factors of ASX. Therefore, microalgae biomass should be considered in the future for further antiviral activities. Full article
(This article belongs to the Special Issue Virus–Host Cell Interactions and Research of New Antivirals)
16 pages, 755 KiB  
Article
Effects of Dietary Tannic Acid and Tea Polyphenol Supplementation on Rumen Fermentation, Methane Emissions, Milk Protein Synthesis and Microbiota in Cows
by Rong Zhao, Jiajin Sun, Yitong Lin, Haichao Yan, Shiyue Zhang, Wenjie Huo, Lei Chen, Qiang Liu, Cong Wang and Gang Guo
Microorganisms 2025, 13(8), 1848; https://doi.org/10.3390/microorganisms13081848 (registering DOI) - 7 Aug 2025
Abstract
To develop sustainable strategies for mitigating ruminal methanogenesis and improving nitrogen efficiency in dairy systems, this study investigated how low-dose tannic acid (T), tea polyphenols (TP), and their combination (T+TP; 50:50) modulate rumen microbiota and function. A sample of Holstein cows were given [...] Read more.
To develop sustainable strategies for mitigating ruminal methanogenesis and improving nitrogen efficiency in dairy systems, this study investigated how low-dose tannic acid (T), tea polyphenols (TP), and their combination (T+TP; 50:50) modulate rumen microbiota and function. A sample of Holstein cows were given four dietary treatments: (1) control (basal diet); (2) T (basal diet + 0.4% DM tannic acid); (3) TP (basal diet + 0.4% DM tea polyphenols); and (4) T+TP (basal diet + 0.2% DM tannic acid + 0.2% DM tea polyphenols). We comprehensively analyzed rumen fermentation, methane production, nutrient digestibility, milk parameters, and microbiota dynamics. Compared with the control group, all diets supplemented with additives significantly reduced enteric methane production (13.68% for T, 11.40% for TP, and 10.89% for T+TP) and significantly increased milk protein yield. The crude protein digestibility significantly increased in the T group versus control. The results did not impair rumen health or fiber digestion. Critically, microbiota analysis revealed treatment-specific modulation: the T group showed decreased Ruminococcus flavefaciens abundance, while all tannin treatments reduced abundances of Ruminococcus albus and total methanogens. These microbial shifts corresponded with functional outcomes—most notably, the T+TP synergy drove the largest reductions in rumen ammonia-N (34.5%) and milk urea nitrogen (21.1%). Supplementation at 0.4% DM, particularly the T+TP combination, effectively enhances nitrogen efficiency and milk protein synthesis while reducing methane emissions through targeted modulation of key rumen microbiota populations, suggesting potential sustainability benefits linked to altered rumen fermentation. Full article
(This article belongs to the Section Veterinary Microbiology)
16 pages, 601 KiB  
Article
Pelleted Sulla Forage (Hedysarum coronarium L.) as a Resource for Sheep Feeding Systems: In Vitro Nutritional Value and Sustainability Perspectives
by Barbara Piccirillo, Marialetizia Ponte, Marianna Pipi, Antonino Di Grigoli, Adriana Bonanno, Monica I. Cutrignelli, Alessandro Vastolo and Serena Calabrò
Animals 2025, 15(15), 2322; https://doi.org/10.3390/ani15152322 (registering DOI) - 7 Aug 2025
Abstract
Enhancing forage protein is key to sustainable ruminant nutrition. The nutritive value of Hedysarum coronarium L. was investigated by studying different preservation systems (fresh vs. dehydrated pellet vs. hay) (Exp. 1) and morphological fractions (flowers vs. leaves vs. stems) (Exp. 2). For the [...] Read more.
Enhancing forage protein is key to sustainable ruminant nutrition. The nutritive value of Hedysarum coronarium L. was investigated by studying different preservation systems (fresh vs. dehydrated pellet vs. hay) (Exp. 1) and morphological fractions (flowers vs. leaves vs. stems) (Exp. 2). For the fresh and pelleted systems, two cuts were used. Proximately, total polyphenols and condensed tannins were detected. In vitro fermentation characteristics were studied by incubating samples with buffered sheep rumen fluid, estimating methane production by volatile fatty acids. Fresh and pelleted sulla were more nutritionally advantageous than hay, in terms of metabolizable energy and protein-to-fiber ratio. Pelleting at the beginning of flowering proved to be a suitable forage for sheep feeding due to protein (15.1% DM), metabolizable energy (9.64 MJ/kg DM), structural carbohydrates (39.5% DM), and total polyphenols (13.5 GAE g/kg DM) content. This cut showed an in vitro fermentation rate (9.86 mL/h), organic matter degradability (55.7%), and volatile fatty acids (87.3 mmoL/g) that were higher (p < 0.05) than hay. Flowers and leaves showed higher (p < 0.05) levels of secondary metabolites than stems as well as lower methane production. These results suggest the potential influence of these compounds in reducing rumen emissions. Dehydration and pelleting resulted in an effective preservation method for maintaining nutrients in sulla forage. Full article
(This article belongs to the Section Animal Nutrition)
16 pages, 610 KiB  
Review
From Deficiency to Therapy: Systemic Consequences of ALAS1 Disruption and the Protective Role of 5-ALA
by Koen van Wijk and Osamu Nakajima
Life 2025, 15(8), 1259; https://doi.org/10.3390/life15081259 (registering DOI) - 7 Aug 2025
Abstract
Heme, an essential prosthetic group involved in mitochondrial respiration and transcriptional regulation, is synthesized via the rate-limiting enzyme 5-aminolevulinic acid synthase (ALAS). Utilizing heterozygous mouse models for ALAS1 and ALAS2, our studies have revealed diverse systemic consequences of chronic heme deficiency. ALAS1-heterozygous (ALAS1+/−) [...] Read more.
Heme, an essential prosthetic group involved in mitochondrial respiration and transcriptional regulation, is synthesized via the rate-limiting enzyme 5-aminolevulinic acid synthase (ALAS). Utilizing heterozygous mouse models for ALAS1 and ALAS2, our studies have revealed diverse systemic consequences of chronic heme deficiency. ALAS1-heterozygous (ALAS1+/−) mice develop metabolic dysfunction characterized by insulin resistance, glucose intolerance, and abnormal glycogen accumulation, linked mechanistically to reduced AMP-activated protein kinase (AMPK) signaling. These mice also exhibit pronounced mitochondrial dysfunction, impaired autophagy, and accelerated aging phenotypes, including sarcopenia and metabolic decline, highlighting heme’s role as a critical metabolic regulator. Additionally, ALAS2 heterozygosity (ALAS2+/−) leads to impaired erythropoiesis, resulting in anemia and ineffective iron utilization. Importantly, supplementation with the heme precursor 5-aminolevulinic acid (5-ALA) significantly mitigates ALAS1+/− phenotypes, restoring metabolic function, mitochondrial health, autophagy, and immune competence. This review encapsulates key findings from our group’s research together with advances made by multiple research groups over the past decade, collectively establishing heme homeostasis as a central regulator of systemic physiology and highlighting the therapeutic potential of 5-ALA in treating heme-deficient pathologies. Full article
Show Figures

Figure 1

33 pages, 732 KiB  
Review
Transforming By-Products into Functional Resources: The Potential of Cucurbitaceae Family Seeds in Cosmetics
by Carla Sousa, Carla Guimarães Moutinho, Márcia Carvalho, Carla Matos and Ana Ferreira Vinha
Seeds 2025, 4(3), 36; https://doi.org/10.3390/seeds4030036 (registering DOI) - 7 Aug 2025
Abstract
Seeds of Cucurbitaceae crops represent a promising yet underexplored source of bioactive compounds with potential applications beyond nutrition, particularly in the cosmetics industry. This review examines the seeds of Citrullus lanatus (watermelon), Cucumis melo (melon), and Cucurbita pepo (pumpkin), focusing on their biochemical [...] Read more.
Seeds of Cucurbitaceae crops represent a promising yet underexplored source of bioactive compounds with potential applications beyond nutrition, particularly in the cosmetics industry. This review examines the seeds of Citrullus lanatus (watermelon), Cucumis melo (melon), and Cucurbita pepo (pumpkin), focusing on their biochemical composition and evaluating their functional value in natural cosmetic development. Although these fruits are widely consumed, industrial processing generates substantial seed by-products that are often discarded. These seeds are rich in polyunsaturated fatty acids, proteins, carbohydrates, and phytochemicals, positioning them as sustainable raw materials for value-added applications. The incorporation of seed-derived extracts into cosmetic formulations offers multiple skin and hair benefits, including antioxidant activity, hydration, and support in managing conditions such as hyperpigmentation, acne, and psoriasis. They also contribute to hair care by improving oil balance, reducing frizz, and enhancing strand nourishment. However, challenges such as environmental instability and low dermal permeability of seed oils have prompted interest in nanoencapsulation technologies to improve delivery, stability, and efficacy. This review summarizes current scientific findings and highlights the potential of Cucurbitaceae seeds as innovative and sustainable ingredients for cosmetic and personal care applications. Full article
18 pages, 2972 KiB  
Article
Flavonoids from Cercidiphyllum japonicum Exhibit Bioactive Potential Against Skin Aging and Inflammation in Human Dermal Fibroblasts
by Minseo Kang, Sanghyun Lee, Dae Sik Jang, Sullim Lee and Daeyoung Kim
Curr. Issues Mol. Biol. 2025, 47(8), 631; https://doi.org/10.3390/cimb47080631 - 7 Aug 2025
Abstract
With increasing interest in natural therapeutic strategies for skin aging, plant-derived compounds have gained attention for their potential to protect against oxidative stress and inflammation. In this study, we investigated the anti-aging and anti-inflammatory effects of flavonoids isolated from Cercidiphyllum japonicum using a [...] Read more.
With increasing interest in natural therapeutic strategies for skin aging, plant-derived compounds have gained attention for their potential to protect against oxidative stress and inflammation. In this study, we investigated the anti-aging and anti-inflammatory effects of flavonoids isolated from Cercidiphyllum japonicum using a tumor necrosis factor-alpha (TNF-α)-stimulated normal human dermal fibroblast (NHDF) model. The aerial parts of C. japonicum were extracted and analyzed by high-performance liquid chromatography (HPLC), leading to the identification of four major compounds: maltol, chlorogenic acid, ellagic acid, and quercitrin. Each compound was evaluated for its antioxidant and anti-aging activities in TNF-α-stimulated NHDFs. Among them, ellagic acid exhibited the most potent biological activity and was selected for further mechanistic analysis. Ellagic acid significantly suppressed intracellular reactive oxygen species (ROS) generation and matrix metalloproteinase-1 (MMP-1) secretion (both p < 0.001), while markedly increasing type I procollagen production (p < 0.01). Mechanistic studies demonstrated that ellagic acid inhibited TNF-α-induced phosphorylation of mitogen-activated protein kinases (MAPKs), downregulated cyclooxygenase-2 (COX-2), and upregulated heme oxygenase-1 (HO-1), a key antioxidant enzyme. Additionally, ellagic acid attenuated the mRNA expression of inflammatory cytokines, including interleukin-6 (IL-6) and interleukin-8 (IL-8), indicating its broad modulatory effects on oxidative and inflammatory pathways. Collectively, these findings suggest that ellagic acid is a promising plant-derived bioactive compound with strong antioxidant and anti-inflammatory properties, offering potential as a therapeutic agent for the prevention and treatment of skin aging. Full article
(This article belongs to the Section Bioorganic Chemistry and Medicinal Chemistry)
Show Figures

Figure 1

13 pages, 1472 KiB  
Article
Effect of Hydrothermal Pretreatment Time on Biochemical Recovery and Hydrogen Production from Lignocellulosic Feedstocks
by Amer Rouabhia, Carlos José Álvarez-Gallego and Luis Alberto Fernández-Güelfo
Appl. Sci. 2025, 15(15), 8736; https://doi.org/10.3390/app15158736 - 7 Aug 2025
Abstract
This study examines the impact of hydrothermal pretreatment operation time (10, 20, and 30 min) on the following four lignocellulosic feedstocks with different lignin content: sugar beet pulp (SBP), brewers spent grain (BSG), orange peel (OP), and rice husk (RH). The objective of [...] Read more.
This study examines the impact of hydrothermal pretreatment operation time (10, 20, and 30 min) on the following four lignocellulosic feedstocks with different lignin content: sugar beet pulp (SBP), brewers spent grain (BSG), orange peel (OP), and rice husk (RH). The objective of pretreatment is twofold, as follows: (1) to enhance the organic matter solubilization and the release of value-added bioproducts, such as total reducing sugars (TRS), total proteins (PR), and volatile fatty acids (VFAs); and (2) to improve VFA and hydrogen production during a subsequent stage of acidogenic anaerobic digestion (Dark Fermentation, DF). In this context, OP reported the highest overall yields across all pretreatment durations. Specifically, at 30 min, it achieved a maximum solubilization of 57.3 gO2/L in terms of soluble chemical oxygen demand (sCOD), 19.1 gTRS/L and 20.6 gPR/L. Regarding VFA and hydrogen production via dark fermentation, the best results were obtained with SBP pretreated for 20 and 30 min, yielding 15.1 g H-Ac/L and 97.5 mL H2 (n.c.)/g (d.m.), respectively. BSG displayed an intermediate performance, whereas RH consistently showed the lowest yields across all evaluated parameters, primarily due to its high lignin content. These findings highlight the pivotal role of pretreatment duration in the valorization of lignocellulosic biomasses, primarily aimed at the recovery of high-value-added biochemicals and biofuels, such as hydrogen, thereby supporting the development of integrated biorefinery systems. Full article
Show Figures

Figure 1

14 pages, 632 KiB  
Article
Protein Polarimetry, Perfected: Specific Rotation Measurement for the Refracto-Polarimetric Detection of Cryptic Protein Denaturation
by Lisa Riedlsperger, Heinz Anderle, Andreas Schwaighofer and Martin Lemmerer
Biophysica 2025, 5(3), 34; https://doi.org/10.3390/biophysica5030034 - 7 Aug 2025
Abstract
Protein polarimetry has been evaluated as a simple and straightforward technique to detect the cryptic denaturation of exemplary proteins. The general rules of rotation vs. amino acid and structural composition and the respective knowledge gaps were reviewed, and the specific rotation of cystine [...] Read more.
Protein polarimetry has been evaluated as a simple and straightforward technique to detect the cryptic denaturation of exemplary proteins. The general rules of rotation vs. amino acid and structural composition and the respective knowledge gaps were reviewed, and the specific rotation of cystine was determined in 4 M NaCl solution as [α]D20 = –302.5°. The specific rotations at 589 nm and 436 nm and the ratio were measured for several model proteins, some purified plasma-derived proteins and for three monoclonal antibodies. The immunoglobulin G concentrates all showed a narrow ratio range likely characteristic for this protein class. Heat denaturation experiments were conducted at temperatures between 50 and 85 °C both for short-time (10 min) and for prolonged periods of heat exposure (up to 210 min). Denaturation by heat resulted not only in the known levorotatory shift, but also in a shift in the specific rotation ratio. The stabilizing effect of fatty acids in bovine serum could be demonstrated by this parameter. Polarimetry thus appears to be a particularly sensitive and simple method for the characterization of the identity and the thermal stability of proteins and should therefore be added again as a complimentary method to the toolbox of protein chemistry. Full article
(This article belongs to the Special Issue Investigations into Protein Structure)
Show Figures

Figure 1

20 pages, 4401 KiB  
Article
Effect of Slightly Acidic Electrolyzed Water Combined with Nano-Bubble Sterilization on Quality of Larimichthys crocea During Refrigerated Storage
by Jiehui Zhong, Hongjin Deng, Na Lin, Mengyao Zheng, Junjie Wu, Quanyou Guo and Saikun Pan
Foods 2025, 14(15), 2754; https://doi.org/10.3390/foods14152754 - 7 Aug 2025
Abstract
The large yellow croaker (Larimichthys crocea) is susceptible to microbial contamination during storage due to its high protein and moisture contents. This study was designed to find a new way to reduce bacteria in large yellow croakers by combining slightly acidic [...] Read more.
The large yellow croaker (Larimichthys crocea) is susceptible to microbial contamination during storage due to its high protein and moisture contents. This study was designed to find a new way to reduce bacteria in large yellow croakers by combining slightly acidic electrolyzed water (SAEW) with nano-bubble (NB) technology. Exploring the effects of available chlorine concentration (ACC), processing time, and water temperature on the bacteria reduction effect of the SAEW-NB treatment for large yellow croakers. Also, the effects of the SAEW-NB combined treatment on sensory evaluation, total viable counts (TVCs), total volatile basic nitrogen (TVB-N), texture, taste profile, and volatile flavor compounds of large yellow croakers were analyzed during the storage period at 4 °C. The results show that the SAEW-NB treatment achieved significantly enhanced microbial reduction compared to individual treatments. Under the conditions of a 4 °C water temperature, 40 mg/L ACC, and 15 min treatment, the SAEW-NB treatment inhibited the increases in physical and chemical indexes such as TVC and TVB-N, maintained the fish texture, and delayed the production of off-flavor volatiles such as aldehydes, alcohols, esters, and ketones, compared with the control group (CG) during storage at 4 °C. In conclusion, the SAEW-NB treatment could better retard fish spoilage, extending the shelf life by approximately 2 days. It might be a promising new industrial approach for large yellow croakers’ storage. Full article
(This article belongs to the Special Issue Innovative Muscle Foods Preservation and Packaging Technologies)
Show Figures

Figure 1

21 pages, 7477 KiB  
Article
Bidirectional Hypoxic Extracellular Vesicle Signaling Between Müller Glia and Retinal Pigment Epithelium Regulates Retinal Metabolism and Barrier Function
by Alaa M. Mansour, Mohamed S. Gad, Samar Habib and Khaled Elmasry
Biology 2025, 14(8), 1014; https://doi.org/10.3390/biology14081014 - 7 Aug 2025
Abstract
The retina is highly sensitive to oxygen and blood supply, and hypoxia plays a key role in retinal diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD). Müller glial cells, which are essential for retinal homeostasis, respond to injury and hypoxia [...] Read more.
The retina is highly sensitive to oxygen and blood supply, and hypoxia plays a key role in retinal diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD). Müller glial cells, which are essential for retinal homeostasis, respond to injury and hypoxia with reactive gliosis, characterized by the upregulation of the glial fibrillary acidic protein (GFAP) and vimentin, cellular hypertrophy, and extracellular matrix changes, which can impair retinal function and repair. The retinal pigment epithelium (RPE) supports photoreceptors, forms part of the blood–retinal barrier, and protects against oxidative stress; its dysfunction contributes to retinal degenerative diseases such as AMD, retinitis pigmentosa (RP), and Stargardt disease (SD). Extracellular vesicles (EVs) play a crucial role in intercellular communication, protein homeostasis, and immune modulation, and have emerged as promising diagnostic and therapeutic tools. Understanding the role of extracellular vesicles’ (EVs’) signaling machinery of glial cells and the retinal pigment epithelium (RPE) is critical for developing effective treatments for retinal degeneration. In this study, we investigated the bidirectional EV-mediated crosstalk between RPE and Müller cells under hypoxic conditions and its impact on cellular metabolism and retinal cell integrity. Our findings demonstrate that RPE-derived extracellular vesicles (RPE EVs) induce time-dependent metabolic reprogramming in Müller cells. Short-term exposure (24 h) promotes pathways supporting neurotransmitter cycling, calcium and mineral absorption, and glutamate metabolism, while prolonged exposure (72 h) shifts Müller cell metabolism toward enhanced mitochondrial function and ATP production. Conversely, Müller cell-derived EVs under hypoxia influenced RPE metabolic pathways, enhancing fatty acid metabolism, intracellular vesicular trafficking, and the biosynthesis of mitochondrial co-factors such as ubiquinone. Proteomic analysis revealed significant modulation of key regulatory proteins. In Müller cells, hypoxic RPE-EV exposure led to reduced expression of Dyskerin Pseudouridine Synthase 1 (DKc1), Eukaryotic Translation Termination Factor 1 (ETF1), and Protein Ser/Thr phosphatases (PPP2R1B), suggesting alterations in RNA processing, translational fidelity, and signaling. RPE cells exposed to hypoxic Müller cell EVs exhibited elevated Ribosome-binding protein 1 (RRBP1), RAC1/2, and Guanine Nucleotide-Binding Protein G(i) Subunit Alpha-1 (GNAI1), supporting enhanced endoplasmic reticulum (ER) function and cytoskeletal remodeling. Functional assays also revealed the compromised barrier integrity of the outer blood–retinal barrier (oBRB) under hypoxic co-culture conditions. These results underscore the adaptive but time-sensitive nature of retinal cell communication via EVs in response to hypoxia. Targeting this crosstalk may offer novel therapeutic strategies to preserve retinal structure and function in ischemic retinopathies. Full article
Show Figures

Graphical abstract

18 pages, 2516 KiB  
Article
Joint Metabolomics and Transcriptomics Reveal Rewired Glycerophospholipid and Arginine Metabolism as Components of BRCA1-Induced Metabolic Reprogramming in Breast Cancer Cells
by Thomas Lucaora and Daniel Morvan
Metabolites 2025, 15(8), 534; https://doi.org/10.3390/metabo15080534 - 7 Aug 2025
Abstract
Background/Objectives: The breast cancer susceptibility gene 1 (BRCA1) is a tumor suppressor gene whose mutations are associated with increased susceptibility to develop breast or ovarian cancer. BRCA1 mainly exerts its protective effects through DNA double-strand break repair. Although not itself [...] Read more.
Background/Objectives: The breast cancer susceptibility gene 1 (BRCA1) is a tumor suppressor gene whose mutations are associated with increased susceptibility to develop breast or ovarian cancer. BRCA1 mainly exerts its protective effects through DNA double-strand break repair. Although not itself a transcriptional factor, BRCA1, through its multiple protein interaction domains, exerts transcriptional coregulation. In addition, BRCA1 expression alters cellular metabolism including inhibition of de novo fatty acid synthesis, changes in cellular bioenergetics, and activation of antioxidant defenses. Some of these actions may contribute to its global oncosuppressive effects. However, the breadth of metabolic pathways reprogrammed by BRCA1 is not fully elucidated. Methods: Breast cancer cells expressing BRCA1 were investigated by multiplatform metabolomics, metabolism-related transcriptomics, and joint metabolomics/transcriptomics data processing techniques, namely two-way orthogonal partial least squares and pathway analysis. Results: Joint analyses revealed the most important metabolites, genes, and pathways of metabolic reprogramming in BRCA1-expressing breast cancer cells. The breadth of metabolic reprogramming included fatty acid synthesis, bioenergetics, HIF-1 signaling pathway, antioxidation, nucleic acid synthesis, and other pathways. Among them, rewiring of glycerophospholipid (including phosphatidylcholine, -serine and -inositol) metabolism and increased arginine metabolism have not been reported yet. Conclusions: Rewired glycerophospholipid and arginine metabolism were identified as components of BRCA1-induced metabolic reprogramming in breast cancer cells. The study helps to identify metabolites that are candidate biomarkers of the BRCA1 genotype and metabolic pathways that can be exploited in targeted therapies. Full article
(This article belongs to the Section Cell Metabolism)
Show Figures

Figure 1

29 pages, 13705 KiB  
Article
Stabilization of Zwitterionic Versus Canonical Glycine by DMSO Molecules
by Verónica Martín, Alejandro Colón, Carmen Barrientos and Iker León
Pharmaceuticals 2025, 18(8), 1168; https://doi.org/10.3390/ph18081168 - 6 Aug 2025
Abstract
Background/Objectives: Understanding the stabilization mechanisms of amino acid conformations in different solvent environments is crucial for elucidating biomolecular interactions and crystallization processes. This study presents a comprehensive computational investigation of glycine, the simplest amino acid, in both its canonical and zwitterionic forms [...] Read more.
Background/Objectives: Understanding the stabilization mechanisms of amino acid conformations in different solvent environments is crucial for elucidating biomolecular interactions and crystallization processes. This study presents a comprehensive computational investigation of glycine, the simplest amino acid, in both its canonical and zwitterionic forms when interacting with dimethyl sulfoxide (DMSO) molecules. Methods: Using density functional theory (DFT) calculations at the B3LYP/6-311++G(d,p) level with empirical dispersion corrections, we examined the conformational landscape of glycine–DMSO clusters with one and two DMSO molecules, as well as implicit solvent calculations, and compared them with analogous water clusters. Results: Our results demonstrate that while a single water molecule is insufficient to stabilize the zwitterionic form of glycine, one DMSO molecule successfully stabilizes this form through specific interactions between the S=O and the methyl groups of DMSO and the NH3+ and the oxoanion group of zwitterionic glycine, respectively. Topological analysis of the electron density using QTAIM and NCI methods reveals the nature of these interactions. When comparing the relative stability between canonical and zwitterionic forms, we found that two DMSO molecules significantly reduce the energy gap to approximately 12 kJ mol−1, suggesting that increasing DMSO coordination could potentially invert this stability. Implicit solvent calculations indicate that in pure DMSO medium, the zwitterionic form becomes more stable below 150 K, while remaining less stable at room temperature, contrasting with aqueous environments where the zwitterionic form predominates. Conclusions: These findings provide valuable insights into DMSO’s unique role in biomolecular stabilization and have implications for protein crystallization protocols where DMSO is commonly used as a co-solvent. Full article
(This article belongs to the Special Issue Classical and Quantum Molecular Simulations in Drug Design)
Show Figures

Graphical abstract

Back to TopTop