A multifactorial study of in situ antioxidant activity of modified GrO in myocardial reperfusion injury using the Langerdorff model

Carbon nanomaterials possess antioxidant properties that can be applied in biomedicine and clinics for the development of new highly effective treatments against oxidative stress-induced diseases like ischemic heart disease. We previously reported the usage of graphene oxide (GrO) as a precursor for the elaboration of such prototypes. The promising findings led to the development of two new modifications of GrO: nitrogen-doped (N-GrO) and l-cysteine functionalized (S-GrO) derivatives as possible antioxidant agents in ischemia-reperfusion (I/R) conditions. In this study, the cardioprotective and antioxidant potential of modified GrO as a pre-treatment in rats was evaluated for the first time. In Langendorff isolated rat heart I/R model, the left ventricle developed pressure (LVDP), the end-diastolic pressure (EDP), the maximal (dP/dtmax) and minimal (dP/dtmin) value of the first derivative of LVDP, and heart rate (HR) were measured. The oxidative-nitrosative markers, in particular, the rate of O2*- and H2O2 generation, the content of malonic dialdehyde, diene conjugates, and leukotriene as well as cNOS and iNOS activity were estimated. Obtained results show a significant restoration of cadiodynamic parameters at the reperfusion period. Simultaneously, all samples significantly reduced the rate of reactive oxygen species (ROS) and lipid peroxidation markers in cardiac homogenates and preserved cNOS activity at the preischemic level. This evidence makes GrO derivatives promising candidates for the correction of reperfusion disorders affecting myocardial function.

Effects of green tea polyphenols against metal-induced genotoxic damage: underlying mechanistic pathways

This review is based upon evidence from the published effects of green tea polyphenols (GTP) on genotoxic damage induced by metals with carcinogenic potential. First, the relationship between GTP and antioxidant defense system is provided. Subsequently, the processes involved in the oxidative stress generated by metals and their relationship to oxidative DNA damage is examined. The review demonstrated that GTP generally decrease oxidative DNA damage induced by exposure to metals such as arsenic (As), cadmium (Cd), cobalt (Co), copper (Cu), chromium (Cr), iron (Fe), and lead (Pb). The pathways involved in these effects are related to: (1) direct scavenging of free radicals (FR); (2) activation of mechanisms to repair oxidative DNA damage; (3) regulation of the endogenous antioxidant system; and (4) elimination of cells with genetic damage via apoptosis. The results obtained in the studies reviewed demonstrate potential for possible use of GTP to prevent and treat oxidative damage in populations exposed to metals. Further, GTP may be considered as adjuvants to treatments for metal-associated diseases related to oxidative stress and DNA damage.

Bioengineered dual fluorescent carbon nano dots from Indian long pepper leaves for multifaceted environmental and health utilities

In this article, we present the synthesis of Piper longum leaves-derived ethanolic carbon dots (PLECDs) using the most simplistic environmentally friendly solvothermal carbonization method. The PLECDs fluoresced pink color with maximum emission at 670 nm at 397 nm excitation. Additionally, the dried PLECDs dissolved in water showed green fluorescence with higher emission at 452 nm at 370 nm excitation. The UV spectra showed peaks in the UV region (271.25 nm and 320.79 nm) and a noticeable tail in the visible region, signifying the efficient synthesis of nano-sized carbon particles and the Mie scattering effect. Various functional groups (-OH, -N-H, -C-H, -C = C, -C-N, and -C-O) were identified using Fourier transform infrared spectroscopy (FTIR). Its nanocrystalline property was revealed by the sharp peaks in the X-ray diffraction (XRD). High-resolution transmission electron microscopy (HRTEM) photomicrograph displayed a roughly spherical structure with a mean size of 2.835 nm. The energy dispersive X-ray (EDAX) and X-ray photoelectron spectroscopy (XPS) revealed the elemental abundance of C, O, and N. The high-performance thin-layer chromatography (HPTLC) fingerprint of PLECDs showed an altered pattern than its precursor (Piper longum leaves ethanolic extract or PLLEE). The PLECDs sensed Cu²⁺ selectively with a limit of detection (LOD) and limit of quantification (LOQ) of 0.063 μM and 0.193 μM, respectively. It showed excellent cytotoxicity toward MDA-MB-231 (human breast cancer), SiHa (human cervical carcinoma), and B16F10 (murine melanoma) cell lines with excellent in vitro bioimaging outcomes. It also has free radical scavenging activity. The PLECDs also showed outstanding bacterial biocompatibility, pH-dependent fluorescence stability, photostability, physicochemical stability, and thermal stability.

Toxicological Assessment of Particulate and Metal Hazards Associated with Vaping Frequency and Device Age

Electronic nicotine delivery systems (ENDS) aerosols are complex mixtures of chemicals, metals, and particles that may present inhalation hazards and adverse respiratory health risks. Despite being considered a safer alternative to tobacco cigarettes, metal exposure levels and respiratory effects associated with device aging and vaping frequency have not been fully characterized. In this study, we utilize an automated multi-channel ENDS aerosol generation system (EAGS) to generate aerosols from JUUL pod-type ENDS using tobacco-flavored e-liquid. Aerosol puff fractions (1-50) and (101-150) are monitored and sampled using various collection media. Extracted aerosols are prepared for metal and toxicological analysis using human primary small airway epithelial cells (SAEC). ENDS aerosol-mediated cellular responses, including reactive oxygen species (ROS), oxidative stress, cell viability, and DNA damage, are evaluated after 24 h and 7-day exposures. Our results show higher particle concentrations in later puff fractions (0.135 mg/m3) than in initial puff fractions (0.00212 mg/m3). Later puff fraction aerosols contain higher toxic metal concentrations, including chromium, copper, and lead, which elicit increased levels of ROS followed by significant declines in total glutathione and cell viability. Notably, a 30% increase in DNA damage was observed after 7 days because of later puff fraction exposures. This work is consistent with ENDS aerosols becoming more hazardous across the use of pre-filled pod devices, which may threaten respiratory health.

Spectrophotometric Methods for Measurement of Antioxidant Activity in Food and Pharmaceuticals

In recent years, there has been a growing interest in the application of antioxidants in food and pharmaceuticals due to their association with beneficial health effects against numerous oxidative-related human diseases. The antioxidant potential can be measured by various assays with specific mechanisms of action, including hydrogen atom transfer, single electron transfer, and targeted scavenging activities. Understanding the chemistry of mechanisms, advantages, and limitations of the methods is critical for the proper selection of techniques for the valid assessment of antioxidant activity in specific samples or conditions. There are various analytical techniques available for determining the antioxidant activity of biological samples, including food and plant extracts. The different methods are categorized into three main groups, such as spectrometry, chromatography, and electrochemistry techniques. Among these assays, spectrophotometric methods are considered the most common analytical technique for the determination of the antioxidant potential due to their sensitivity, rapidness, low cost, and reproducibility. This review covers the mechanism of actions and color changes that occur in each method. Furthermore, the advantages and limitations of spectrophotometric methods are described and discussed in this review.

Comparative Evaluation of Physicochemical, Antioxidant, and Sensory Properties of Red Wine as Markers of Its Quality and Authenticity

The consumption of red wine by most wine drinkers has increased significantly because of the perceived health benefits which are linked to its inherent quality characteristics. In the quest to determine the conformity of Nigeria's domestic red wine quality with their international counterparts, the quality characteristics of domestic red wines produced in Nigeria were evaluated using foreign red wines as markers of wine quality and authenticity. Foreign and domestic red wines obtained in Nigeria were analyzed for physicochemical, antioxidant, and sensory properties using standard methods. Results showed that the domestic wines had significantly (p < 0.05) higher pH (4.03–4.16) and total sugar content (8.60–9.27%) while the foreign wines had significantly (p < 0.05) higher total titratable acidity (0.76–0.83%), Brix (6.98–8.04 g/100 g), alcohol (14.44–15.21% ABV), and polyphenol content (385.13–412.75 mg/L). Additionally, the domestic wines exhibited significantly (p < 0.05) lower antioxidant capacity compared to the foreign wines. Although the wines' hue angle (27.68°–41.46°) indicated a red colour spectrum in the visible region of the opponent colour chart, the total colour difference (ΔE) between foreign and domestic wines was significant. The sensory characteristics of the wines differed significantly as the panelist rating for overall acceptance ranged from 5.58 to 7.33. This research has provided valuable insight that the domestic wines studied showed a considerable level of authenticity and different levels of quality according to their varying concentration of organic acids, residual sugars, and phenolic compounds.

Graphene oxide nanoflackes prevent reperfussion injury of Langerdorff isolated rat heart providing antioxidative activity in situ

Carbon materials possess powerful antioxidant activity that might be promising for the development of new generation treatment of cardiovascular diseases, ischemic conditions, and reperfusion injury. The present study aimed to characterize the structure of nanosized graphene oxide (GrO) sample and evaluate the antioxidant efficacy of GrO in situ models of oxidative stress widely used in pre-clinical studies. The structure and surface chemistry of the initial samples were analyzed via LDS, RAMAN, LDI, TPD-MS, and FTIR methods. The GrO showed a strong ability to scavenge DPPH, hydroxyl, and superoxide anion free radicals and have a total antioxidant capacity. The DFT quantum-chemical calculation demonstrated the radical scavenging effect of GrO proceeding due to the physical adsorption of the free radical on the surface. For evaluation of the antioxidant effect of GrO in situ, we used the model of ischemia-reperfusion (I/R) of Langendorff isolated rat heart. We revealed that intravenous pretreatment of Wistar male rats with GrO significantly increased resistance of myocardium to I/R, improved restoration of heart function, prevented non-effective oxygen utilization, and I/R induced reactive oxygen species production in cardiac tissue. Thus, our data demonstrate the perspective of further use of GrO for the development of antiischemic therapy.

Carbon dots from an immunomodulatory plant for cancer cell imaging, free radical scavenging and metal sensing applications

Aim: This work aimed to develop Tinospora cordifolia stem-derived carbon dots (TCSCD) for cancer cell imaging, free radical scavenging and metal sensing applications. Method: The TCSCDs were synthesized by a simple, one-step, and ecofriendly hydrothermal carbonization method and characterized for their optical properties, morphology, hydrodynamic size, surface functionality, crystallinity, stability, bacterial biocompatibility, in vitro cellular imaging, free radical scavenging and metal sensing ability. Results: The TCSCDs exhibited excellent biocompatibility with dose-dependent bioimaging results in melanoma (B16F10) and cervical cancer (SiHa) cell lines. They exerted good free radical scavenging, Fe³⁺ sensing, bacterial biocompatibility, photostability, colloidal dispersion stability and thermal stability. Conclusion: The results reflect the potential of TCSCDs for biomedical and pharmaceutical applications.

Bioactive Sterol Derivatives Isolated from the Pleurotus djamor var. Roseus Induced Apoptosis in Cancer Cell Lines

OBJECTIVE

The aim of the present study is to isolate and characterize the bioactive compounds from Pleurotus djamor against human breast cancer (MDA-MD-231) and mouse T cell lymphoma (EL4) cell lines.

MATERIALS AND METHODS

Sequential fractionization and column chromatography methods were involved in compound isolation. The structures of the isolated compound were determined by NMR, GC/MS, and X-ray crystallography studies.

RESULTS

The isolated compounds 1- 4 [D-mannitol (C1), ergosta-5,7,22-trien-3β-ol (C2), 5,8- epidioxy-ergosta-6-22-dien-3β-ol (C3), and palmitic acid (C4)] are white crystal and amorphous powder in nature. All these compounds were isolated from this mushroom for the first time. In vitro lipid peroxidation activities of isolated compounds were determined by ferric thiocyanate (FTC) and thiobarbituric acid (TBA) method. The sterol derivatives C2 and C3 compounds displayed strong antioxidant activity and were not significantly different (p<0.05) to α-tocopherol. This finding elaborates on the isolation of a cytotoxic compound C2 and C3 from P. djamor via a rapid elution method.

CONCLUSION

The compound C3 has exhibited better cytotoxic activity against MDA-MD-231 and EL4 cells. The present finding and data might provide new insights into the possible therapeutic and pharmaceutical use for the design of anti-cancer drugs from this edible mushroom.