Oxygen, Volume 5, Issue 3 (September 2025) – 11 articles

Background/Objectives: Trypanosoma evansi (T. evansi) is an etiological agent of surra, and it causes significant economic losses in livestock. Rising trypanocide resistance demands alternatives that control parasitemia while mitigating oxidative and genotoxic damage. Therefore, the present study was designed to explore both the in vivo and in silico potential of Zingiber officinale (Z. officinale) as a novel phytotherapy to counter growing resistance against conventional trypanocides. Methods: Methanolic extract of Z. officinale (MZ) was orally administered at dosages of 200 mg/kg (MZ 200), 400 mg/kg (MZ 400), and 800 mg/kg (MZ 800) on a daily basis to the experimentally infected mice and compared against treated control (TC) and untreated control (UC) groups. After the infection, different parameters such as parasitemia counts, body weight changes, and the survival of infected mice were monitored for up to 7 days post-infection, while hematobiochemical parameters, oxidative stress profiles (catalase, malondialdehyde, and superoxide dismutase), and genotoxicity in brain tissues were compared at the end of the trial. Moreover, computational tools were used to predict the affinities of key bioactive compounds with twenty-one essential proteins of T. evansi. Results: The findings showed that the administration of MZ significantly (p < 0.05) reduced parasitemia and improved the survival rates in the experimentally infected mice in a dose-dependent manner. Noteworthy, significant (p < 0.05) improvements in hematological parameters and liver enzyme profiles were also recorded in MZ-treated groups. Compared to the untreated control, MZ-treated groups showed a significant amelioration in oxidative stress and genotoxicity in brain tissue in a dose-dependent fashion. The current study’s findings suggest that MZ potentially inhibits various essential proteins of T. evansi, including adenosine transporter-1, casein kinase, leucyl-tRNA synthetase, and multidrug resistance E protein. Among its constituents, 6-Isoshogaol and 6-Gingerol showed the most stable interactions in the molecular dynamics simulation. Conclusions: MZ efficiently reduced parasitemia, oxidative stress, and genotoxicity, and increased the survival rate in infected mice, suggesting it as a promising natural trypanicidal agent. Full article

Compounds known as liquid organic hydrogen carriers (LOHCs) offer a promising pathway for storing hydrogen. Beyond the use of pure hydrocarbons, the incorporation of oxygen atoms offers a way to modify thermodynamic properties and potentially improve suitability for hydrogen storage. This study explores the effect of oxygen functionalization in aromatic ethers and lactones on the reaction equilibrium of reversible hydrogenation. To address this question, reaction enthalpies and entropies are calculated using both experimental and theoretically determined pure substance data. The equilibrium position shift in the hydrogenation of furan derivatives has been shown to follow a similar trend to that of their hydrocarbon counterparts upon the addition of aromatic rings. This shift is, however, more pronounced in the case of the furan-based systems. The effect is reflected in increasing Gibbs reaction energies during the dehydrogenation process. Both the formation of lactones and the addition of a second ring to the furan core leads to a further increase in the Gibbs reaction energy. The highest value is observed for dibenzofuran, with a Gibbs reaction energy of 36.6 kJ∙mol⁻¹ at 500 K. These findings indicate that, from a thermodynamic perspective, hydrogen release is feasible at temperatures below 500 K, which is an important feature for the potential application as a hydrogen storage system. Full article

Experimental evidence indicates that aqueous extracts of the Cistus genus have significant antioxidant properties, suggesting their potential as food fortifiers. In the present study, the antioxidant capacity and total phenolic content of lyophilized Cistus creticus extract were examined before and after in vitro digestion. Three concentrations of Cistus creticus extract were evaluated before and after in vitro gastrointestinal digestion, along with yogurt products fortified with these extracts, examined after digestion. Biochemical and cellular analyses were performed to assess these properties. The results showed statistically significant differences in total antioxidant capacity and total phenolic content, with values increasing from the lowest to the highest concentration studied, for both the lyophilized extracts and fortified yogurts after digestion. Additionally, cellular antioxidant activity after digestion was concentration-dependent (p < 0.05) within the range 25–500 mg/mL for both the extracts and fortified yogurts. In conclusion, based on the high phenolic content and the increased antioxidant capacity observed in epithelial cells, 250 mg of extract per 200 g of yogurt was proposed as the optimal fortification dose. Full article

Amiodarone (AMD) is an effective antiarrhythmic drug whose long-term use is limited by multi-organ toxicities linked to oxidative stress. This review synthesizes current evidence on how AMD induces reactive oxygen species (ROS) generation in vitro and in vivo, and the mechanistic pathways involved. AMD promotes ROS production through both direct and indirect mechanisms. Directly, AMD accumulates in mitochondria and impairs the electron transport chain, leading to electron leakage and superoxide formation. It also undergoes redox cycling, forming radical intermediates that trigger lipid peroxidation and deplete cellular antioxidants. AMD and its metabolites inhibit antioxidant enzymes (SOD, CAT, GPx) expression and/or activities and reduce glutathione level, compounding oxidative injury. Indirectly, AMD activates signaling pathways that exacerbate ROS generation. This compound can induce pro-inflammatory mediators such as TNF-α and modulate nuclear receptors such as AhR, PXR, CAR, and PPARs, altering the expression of metabolic enzymes and endogenous antioxidants. These processes are time- and dose-dependent: short exposures at low concentrations may transiently scavenge radicals, whereas chronic or higher-dose exposures consistently lead to net ROS accumulation. The oxidative effects of AMD vary by tissue and experimental models. In chronic models, organs such as the lung and liver show pronounced ROS-mediated injury, whereas acute or cell-based systems typically exhibit subtler changes. AMD-induced toxicity arises from multifactorial oxidative stress involving mitochondrial dysfunction, increased radical formation, depletion of antioxidant defenses, and activation of pro-oxidant signaling pathways. Recognizing these pathways suggests that antioxidant and mitochondria-targeted co-therapies could ameliorate the side effects of AMD. Full article

Cadmium (Cd) is a highly toxic heavy metal that disrupts development and reproduction, primarily through oxidative stress. In this context, sulforaphane (SFN), an antioxidant compound, may serve as a promising agent to counteract Cd-induced oxidative damage and prevent developmental and reproductive abnormalities. This study aimed to evaluate the effect of SFN on reproductive toxicity induced by cadmium chloride (CdCl₂) in the nematode Caenorhabditis elegans (C. elegans). Five experimental groups were established: (I) Control: no treatment, (II) dimethyl sulfoxide (DMSO): 48 h with 0.01% DMSO, (III) CdCl₂: 24 h with 4600 µM CdCl₂, (IV) SFN + CdCl₂: 24 h with 100 µM SFN followed by 24 h with both SFN and CdCl₂, and (V) SFN: 48 h with 100 µM SFN. Co-exposure to SFN and CdCl₂ prevented the reduction in the percentage of adult nematodes and increased egg-laying. It also significantly improved hatching rates, allowing more embryos to reach the larval stage, and prevented reductions in body size. However, no effects were observed on glutathione S-transferase-4 (GST-4) levels in the transgenic CL2166 strain. In conclusion, SFN substantially prevents Cd-induced reproductive toxicity in C. elegans. Future studies should investigate the molecular mechanisms by which SFN enhances egg-laying and offspring viability in this model. Full article

Seven lager beers and seven non-alcoholic counterparts, marketed by the same producers, were analyzed for their total phenolic content (TPC), radical scavenging activity (RSA) towards the DPPH radical and ThioBarbituric Index (TBI). All beers were also subjected to spin trapping experiments at 60 °C in the presence of PBN. To our knowledge, this is the first time that non-alcoholic beers (NABs) have been subjected to spin trapping experiments coupled with Electron Spin Resonance (ESR) spectroscopy. The evolution of the intensity of the PBN radical adducts during the first 150 min was represented graphically and the intensity at 150 min (I₁₅₀) and the area under the curve (AUC), were measured. The I₁₅₀ and the AUC of lagers and NABs are significantly different, whereas the TPC, the EC₅₀ of the DPPH assay, and the TBI of the two groups are superimposed. A relationship, previously proposed by us, to correlate ESR spectroscopy parameters with others obtained from UV-Vis spectrophotometry, was also applied, demonstrating its practicability. Multivariate analysis shows that clustering in two separate groups occurs only if I₁₅₀ and AUC are included in the model. Based on these results, ESR spectroscopy can be applied to study the oxidative stability of NABs. Full article

Introduction: Rapid ascent to altitudes of over 5000 m above sea level are associated with dramatic changes in adaptive physiology. The effects of a gradual ascent on symptoms, oximetry, and heart rate are described and compared with the effects of a rapid ascent to the same altitude by a comparable cohort. Methods: A group of 13 individuals (six females) representing 10 countries from five continents ascended gradually from Lukla (2300 m) to Everest Base Camp (5300 m) in Nepal over an 8-day period, then descended over a further 4 days. All symptoms and medication were recorded, along with pulse oximetry (SpO₂) and heart rate (HR) every 500 m of ascent. The results were then compared with those obtained at equivalent altitudes using similar methodology from a fast ascent of Mount Kilimanjaro to an equivalent altitude by a comparable cohort over 4 days. Results: The gradual ascent group had a median age of 33 years (range 25–66), and all successfully completed the trek. No severe headache, vomiting, orthopnoea, or productive cough occurred, although minor nausea and mild headache were common. Baseline oximetry fell from a median of 96% (93–97%) to a median of 78% (53–86%) at 8 days but recovered to 94% (89–99%) inside 4 days. Corresponding HR rose from a baseline median of 72 bpm (57–85) to a median of 103 bpm (78–115) at 8 days, then recovered to 80 bpm (54–94) after 4 days. Neither age nor gender correlated with outcomes. Individually, HR correlated inversely with oximetry, but there was no group correlation between these two variables. By contrast, a more rapid 4-day ascent from the same starting height, with similar baseline values for HR and oximetry, to the same final altitude was associated with more severe headache, breathlessness, and vomiting. Fast ascent was associated with a significantly more marked reduction in oximetry to a median of 71% (52–76) and an increase in HR to a median of 110 bpm (88–140). The fast ascent group also required significantly more medication, rated their experience as less enjoyable, and had a 100% incidence of acute mountain sickness compared to 0% in the slow ascent group. Discussion: Oxygen desaturation and tachycardia are inevitable consequences of ascending above 5000 m, but the degree to which this occurs can be reduced by slowing ascent times and taking rest days every 1000 m of ascent. This practice is associated with fewer symptoms and greater safety, with less need for either prophylactic or therapeutic medication. Careful consideration should be given to rates of ascent when climbing to altitudes at or above 5000 m. Full article

(1) Background: Previous studies indicate that individuals who engage in regular physical activity have a higher pain threshold than those who do not exercise. However, it remains unclear how this phenomenon behaves in individuals exposed to chronic hypoxia. This study evaluates pain perception at high altitude between high-altitude natives who exercised regularly and those who did not practice physical activity. (2) Methods: Eighty-four healthy volunteers aged 20 to 30 years old with a body mass index (BMI) within the normal range (18.5–24.9) residing in the city of Puno (3825 m) were recruited. The unilateral ischemia pain provocation test was used, applying pressure with a manual sphygmomanometer to generate transient ischemia in the arm while the patient opens and closes their hand. Onset, peak, and resolution times of pain, heart rate, and oxygen saturation were recorded. (3) Results: The average time to pain onset in the right arm was 30.2 s ± 14.1 during light physical activity, whereas, during moderate physical activity, it increased to 32.5 s ± 15.4. In the left arm, the average time until pain sensation was 27.9 s ± 16.8 during light physical activity and increased to 34.6 s ± 18.5 with moderate physical activity. Regarding the progression of pain intensity, the average time to reach unbearable pain in the right arm was 54.1 s ± 16.4 during light physical activity and 53.8 s ± 19.6 during moderate physical activity; in the left arm, it was 53.0 s ± 19.6 during light physical activity, increasing to 59.3 s ± 24.5 during moderate physical activity. (4) Conclusions: A more stable and slightly higher pain tolerance in the dominant arm was observed. Full article

Platinum-based catalysts remain the benchmark for the oxygen reduction reaction (ORR) in fuel cells, owing to their exceptional catalytic activity in the harsh chemical environment. However, optimizing Pt utilization and improving performance through support engineering are essential for commercial viability. In this study, we synthesized carbon-supported binary Pt-M (M = Ni, Cu, Co) electrocatalysts to investigate the influence of metal–support interactions on ORR activity. The Pt-M nanoparticles were fabricated on carbon supports, enabling the systematic screening of electronic and structural interactions. Among all compositions, Pt@Co exhibited the highest ORR mass activity, delivering 817 mA mg_Pt⁻¹ at 0.85 V and 464 mA mg_Pt⁻¹ at 0.90 V vs. RHE, surpassing both commercial Pt/C (J.M. 20 wt.%) and its Pt@Ni, Pt@Cu, and Pt@CNT counterparts. Structural and spectroscopic analyses reveal a strong electronic interaction between Pt and Co, leading to localized electron transfer from Co to Pt domains. This electronic modulation facilitates an optimal surface binding energy, enhancing oxygen adsorption–desorption kinetics and ORR activity. These findings highlight the critical role of transition metal–support synergy in the rational design of high-performance Pt-based electrocatalysts for next-generation fuel cell applications. Full article

Fibromyalgia is a syndrome that causes chronic musculoskeletal pain accompanied by symptoms such as fatigue, sleep disorders, headaches, anxiety, and depression. People diagnosed with fibromyalgia usually have higher levels of reactive oxygen species and lower antioxidant capacity compared to healthy individuals. This condition can contribute to elevated oxidative stress in the body, especially within the lipid-rich nervous system. Treatment with antioxidants through diet or supplements is one method being investigated to reduce the symptoms of fibromyalgia. This narrative review focuses on the latest research, specifically peer-reviewed publications within the last 10 years, on potential antioxidant treatments for patients with fibromyalgia. Relevant micronutrients, such as vitamin B12, vitamin D, and iron, and supplements such as melatonin, coenzyme Q, alpha-lipoic acid, and palmitoylethanolamide are discussed. Based on the current evidence, many of these antioxidants show potential for the management of fibromyalgia symptoms as standalone treatments or in combination with other antioxidants or pharmacological agents. More clinical research is required to understand the long-term efficacy and safety of these micronutrients and supplements, as well as their overall health impact. Full article