Pathophysiological relationship between hypoxia associated oxidative stress,Epithelial-mesenchymal transition,stemness acquisition and alteration of Shh/ Gli-1 axis during oral sub-mucous fibrosis and oral squamous cell carcinoma

Oral sub-mucous fibrosis (OSF) is a pathophysiological state of oral cavity or oropharynx having a high chance of conversion to oral squamous cell carcinoma (OSCC). It involves fibrotic transformation of sub-epithelial matrix along with epithelial abnormalities. The present work aims to unveil the mechanistic domain regarding OSF to OSCC conversion exploring the scenario of hypoxia associated oxidative stress, epithelial-mesenchymal transition (EMT), metastasis and stemness acquisition. The study involves histopathological analysis of the diseased condition along with the exploration of oxidative stress status, assessment of mitochondrial condition, immunohistochemical analysis of HIF-1α, E-cadherin, vimentin, ERK, ALDH-1, CD133, Shh, Gli-1 and survivin expressions in the oral epithelial region together with the quantitative approach towards collagen deposition in the sub-epithelial matrix. Oxidative stress was found to be associated with type-II EMT in case of OSF attributing the development of sub-epithelial fibrosis and type-III EMT in case of OSCC favoring malignancy associated metastasis. Moreover, the acquisition of stemness during OSCC can also be correlated with EMT. Alteration of Shh and Gli-1 expression pattern revealed the mechanistic association of hypoxia with the phenotypic plasticity and disease manifestation in case of OSF as well as OSCC. Shh/ Gli-1 signaling can also be correlated with survivin mediated cytoprotective phenomenon under oxidative stress. Overall, the study established the correlative network of hypoxia associated oxidative stress, EMT and manifestation of oral pre-cancerous and cancerous condition in a holistic approach that may throw rays of hope in the therapeutic domain of the concerned diseases.     

New conservation opportunities: Using citizen science in monitoring non-native species in Neotropical region

The combination of highly equipped smartphones, with the increased use of social media, has offered a wide database. Given this, citizen science can be used to record and monitor non-native fish fauna, target new samples and collaborate with monitoring occurrences in new areas. We aimed to demonstrate the efficiency of social media in citizen science as a tool to cooperate with monitoring studies of non-native species. Consequently, we determined the occurrence points of S. brasiliensis in the Iguaçu River basin, indicating sites of greatest occurrence and analyzing the impact of the invasion on the native fauna of the basin. Files and information available on the YouTube^® and Facebook^® media platforms were used as data, was carried out from April 2019 to April 2020. The results were 40 records, 22 videos obtained from Youtube, and seven videos and 11 photos from Facebook, the oldest record was from April 2013, while the largest number of posts was in 2016. Fish records available from online platforms can reveal the occurrence and progressive dispersion of species, in the context of biological invasions, these tools can be of great value in studies that aim to follow the progress of introduced species, contributing by helping to direct new sampling programs and corroborating the occurrence of species in new areas in conjunction with standard monitoring programs. Based on citizen science records, it was possible to update the range of occurrence of the non-native S. brasiliensis in the Iguaçu River basin, cooperating with scientific knowledge. Innovative monitoring and control measures are necessary to deal with invasive species, with citizen science proving to be competent for determining the occurrence of species and showing promise in the entire field of ichthyology.     

Effects of stocking density during live transportation on haematological parameters of Siberian sturgeon (Acipenser baerii,Brandt, 1869)

In this study, we investigated the effects of different stocking densities water quality and blood parameters during the transportation of the Siberian sturgeon (Acipenser baerii). Experiments were carried out in high-density polyethylene tank with three different stocking densities (50, 100 and 150 kg/m³) for 20 h. Ammonium nitrogen (NH₄-N) and nitrite nitrogen (NO₂-N) were measured in the water samples. The erythrocyte, leucocyte, haematocrit (HCT), haemoglobin (Hb), cortisol, and sodium ion (Na⁺) were measured in blood samples. Ammonium nitrogen and nitrite nitrogen concentrations in the water have increased in parallel with the stocking density depending on the time. In the highest stocking density, the maximum levels of NH₄-N and NO₂-N at the 16^th h reached 2.64 mg/L and 4.74 mg/L, respectively. Erythrocyte, leucocyte, HCT, and Hb values did not differ significantly between the experimental groups (p > .05). The results showed that fish could be transported safely for 20 h in 15℃ water temperature at 50 kg/m³ stocking density; however, stocking density of 100 kg/m³ and over could threaten fish welfare and health as from 16^th h.     

Circulating antioxidant vitamins and copper in Azorean coronary artery disease patients under preventive medication – A case study

Background and aimOxidative stress and inflammation are conditions that are deeply involved in atherosclerosis and consequent coronary artery disease (CAD). Therefore, the aim of this study was to assess the relationship among circulating antioxidant vitamins (C, A, E), copper, and other pro- or antioxidant/inflammation markers in patients with and without CAD under preventive medication.Subjects and methods174 Azorean subjects symptomatic for CAD (age 56 ± 9y; 68 % men) submitted to coronary angiography were split into 2 groups: one formed by CAD patients (≥50 % stenosis in at least one major coronary vessel) and the other by non-CAD patients (<50 % stenosis). Both groups were age-, sex- and BMI-matched. Plasma levels of vitamins or copper were measured by HPLC and AAS, respectively.Results and conclusionsLower vitamin C levels were observed in CAD patients (mainly in women, who exhibited a high rate of diabetes mellitus) as compared to the non-CAD ones. Also, CAD patients (mainly men) exhibited significantly higher concentrations of plasma copper than their non-CAD counterparts (1.17 ± 0.3 mg/L vs. 1.09 ± 0.3 mg/L, p = 0.030). In bivariate analysis, plasma copper levels were positively associated with serum LDL-cholesterol (r=0.22; p = 0.004) and chiefly with C-reactive protein (r=0.40; p < 0.001). Furthermore, they were significantly lower in recurrent vs. non recurrent CAD patients (1.07±0.2 vs. 1.24±0.3 mg/L, p = 0.004). ROC analysis showed that plasma copper, whenever >1.06 mg/L, was an independent risk factor for CAD in primary prevention for men, which suggests that its levels can fluctuate with medical therapy (such as anti-inflammatory), thus indicating that copper is not a reliable marker for CAD. Moreover, plasma copper concentration was not associated with CAD severity. Yet, results do suggest that, even within its reference concentration range, it could be useful as an acute inflammation marker in CAD management.     

Metabolic and oxidative impairments in human salivary gland cells line exposed to MeHg

Background/aimThe ingestion of contaminated seafood by MeHg is considered the main route of human exposure, turning the salivary gland one important target organ. The salivary glands play critical roles in maintaining oral health homeostasis, producing saliva that maintains the oral microbiota, initiation of the digestion of macromolecules, and being essential in maintaining the integrity of the adjacent soft tissues and teeth. Thus, this study aimed to investigate the effects of MeHg exposure on human salivary gland cells line.MethodsCells were exposed to 1–6 μM of MeHg for 24 h, and analysis of toxicity was performed. Based on these results, the LC50 was calculated and two concentrations were chosen (0.25 and 2.5 μM MeHg) to evaluate intracellular mercury (Hg) accumulation (THg), metabolic viability and oxidative stress parameters (GSH:GSSG ratio, lipid peroxidation, protein oxidation and DNA damage).ResultsThe results demonstrated accumulation of THg as we increased the MeHg concentrations in the exposure and, the higher the dose, the lower is the cell metabolic response. In addition, the 2.5 μM MeHg concentration also triggered oxidative stress in human salivary gland cells by depleting the antioxidant competence of GSH:GSSG ratio and increasing lipid peroxidation and proteins carbonyl levels, but no damages to DNA integrity.ConclusionIn conclusion, although these two elected doses did not show lethal effects, the highest dose triggered oxidative stress and new questionings about long-term exposure models are raised to investigate furthers cellular damages to human salivary gland cells caused by MeHg exposure to extrapolate in a translational perspective.     

Prospects and future perspectives of selenium nanoparticles: An insight of growth promoter,antioxidant and anti-bacterial potentials in productivity of poultry

Nanoparticles have been attracted attention in poultry research due to their low toxicity, higher bio-availability, high surface area with sustained drug release. Dietary supplementation with selenium nanoparticles (Se-NPs) plays a regulatory role in maintaining growth performance, feed conversion ratio (FCR), antioxidant defense as well as microbial control. Se-NPs have emerging importance in modulating intestinal health through the maintenance of beneficial microbes (microflora) as well as the production of short-chain fatty acids (SCFA). Se-NPs regulate intrinsic redox status by scavenging free radicals. The antioxidant potentiality of Se-NPs is influenced by the activation of the seleno-enzymes such as thioredoxin reductase and glutathione peroxidase family (GPx) involved in scavenging of Reactive Oxygen Species (ROS). The emerging significance of Se-NPs on antimicrobial activity has been exploited due to their bio-accumulative effects and biocompatibility potentiality in the cellular systems against poultry pathogens. The present review highlights on growth performance, antioxidant defense, and anti-bacterial potentiality of Se-NPs in poultry and also provide insight into its significance in the poultry industry.     

Divergent DNA methylation contributes to duplicated gene evolution and chilling response in tea plants

The tea plant (Camellia sinensis) is a thermophilic cash crop and contains a highly duplicated and repeat-rich genome. It is still unclear how DNA methylation regulates the evolution of duplicated genes and chilling stress in tea plants. We therefore generated a single-base-resolution DNA methylation map of tea plants under chilling stress. We found that, compared with other plants, the tea plant genome is highly methylated in all three sequence contexts, including CG, CHG and CHH (where H = A, T, or C), which is further proven to be correlated with its repeat content and genome size. We show that DNA methylation in the gene body negatively regulates the gene expression of tea plants, whereas non-CG methylation in the flanking region enables a positive regulation of gene expression. We demonstrate that transposable element-mediated methylation dynamics significantly drives the expression divergence of duplicated genes in tea plants. The DNA methylation and expression divergence of duplicated genes in the tea plant increases with evolutionary age and selective pressure. Moreover, we detect thousands of differentially methylated genes, some of which are functionally associated with chilling stress. We also experimentally reveal that DNA methyltransferase genes of tea plants are significantly downregulated, whereas demethylase genes are upregulated at the initial stage of chilling stress, which is in line with the significant loss of DNA methylation of three well-known cold-responsive genes at their promoter and gene body regions. Overall, our findings underscore the importance of DNA methylation regulation and offer new insights into duplicated gene evolution and chilling tolerance in tea plants.