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关键词： lens   cataract   pathogenesis   crystallins   small heat shock proteins   anti-cataract drugs  

摘要： The absence of cellular organelles in fiber cells and very high cytoplasmic protein concentration (up to 900 mg/ml) minimize light scattering in the lens and ensure its transparency. Low oxygen concentration, powerful defense systems (antioxidants, antioxidant enzymes, chaperone-like protein alpha-crystallin, etc.) maintain lens transparency. On the other hand, the ability of crystallins to accumulate age-associated post-translational modifications, which reduce the resistance of lens proteins to oxidative stress, is an important factor contributing to the cataract formation. Here, we suggest a mechanism of cataractogenesis common for the action of different cataractogenic factors, such as age, radiation, ultraviolet light, diabetes, etc. Exposure to these factors leads to the damage and death of lens epithelium, which allows oxygen to penetrate into the lens through the gaps in the epithelial layer and cause oxidative damage to crystallins, resulting in protein denaturation, aggregation, and formation of multilamellar bodies (the main cause of lens opacification). The review discusses various approaches to the inhibition of lens opacification (cataract development), in particular, a combined use of antioxidants and compounds enhancing the chaperone-like properties of alpha-crystallin. We also discuss the paradox of high efficiency of anti-cataract drugs in laboratory settings with the lack of their clinical effect, which might be due to the late use of the drugs at the stage, when the opacification has already formed. A probable solution to this situation will be development of new diagnostic methods that will allow to predict the emergence of cataract long before the manifestation of its clinical signs and to start early preventive treatment.

关键词： Energy expenditure   hyperlipidemia   obesity   overweight   respiratory quotient  

摘要： Objectives The objective of this study was to verify the safety of policosanol supplementation for domestic cats. The effects of raw and encapsulated policosanol were compared with positive (L-carnitine) and negative (no supplementation) controls on outcomes of complete blood count, serum biochemistry, energy expenditure, respiratory quotient and physical activity in healthy young adult cats. Methods The study was a replicated 4 x 4 complete Latin square design. Eight cats (four castrated males, four spayed females;mean age 3.0 +/- 1.0 years;mean weight 4.36 +/- 1.08 kg;mean body condition score 5.4 +/- 1.4) were blocked by sex and body weight then randomized to treatment groups: raw policosanol (10 mg/kg body weight), encapsulated policosanol (50 mg/kg body weight), L-carnitine (200 mg/kg body weight) or no supplementation. Treatments were supplemented to a basal diet for 28 days with a 1-week washout between periods. Food was distributed equally between two offerings to ensure complete supplement consumption (first offering) and measure consumption time (second offering). Blood collection (lipid profile, complete blood count, serum biochemistry) and indirect calorimetry (energy expenditure, respiratory quotient) were conducted at days 0, 14 and 28 of each period. Activity monitors were worn 7 days prior to indirect calorimetry and blood collection. Data were analyzed using a repeated measures mixed model (SAS, v.9.4). Results Food intake and body weight were similar among treatments. There was no effect of treatment on lipid profile, serum biochemistry, activity, energy expenditure or respiratory quotient (P >0.05);however, time to consume a second meal was greatest in cats fed raw policosanol (P <0.05). Conclusions and relevance These data suggest that policosanol is safe for feline consumption. Further studies with cats demonstrating cardiometabolic risk factors are warranted to confirm whether policosanol therapy is an efficacious treatment for hyperlipidemia a

关键词： Acute hepatopancreatic necrosis disease (AHPND)   Pathogenic stress   Penaeus monodon   Serotonin   Gene expression  

摘要： The black tiger shrimp (Penaeus monodon) represents a major crustacean aquaculture species globally. Outbreaks of diseases caused by two particular pathogens, Vibrio parahemolyticus (VP) and white spot syndrome virus (WSSV) severely hamper the production performance of this species. The present study investigated the effects of different doses of the two pathogens on physiological/biochemical parameters and differential gene expression in P. monodon. This study involved 10 different experimental groups including nine treatments (three doses of VP: T-1 - T-3, three doses of WSSV: T-4 - T-6 and three combined VP + WSSV doses: T-7 - T-9) and a control. VP and WSSV treatments significantly reduced hemocyte counts of shrimp hemolymph (P < 0.05). Different treatments showed 2-4 fold increase in hemolymph glucose and serotonin levels over the control shrimps. Pathogenic treatments significantly altered expression pattern of the selected set of candidate genes. The a-amylase (growth gene) showed reduced expression (1.5-3 fold lower) in treatments while immune response genes (Prophenoloxidase and Lysozyme) showed significantly higher expression levels (2-3 fold higher) in treatment groups compared to the control. Significantly higher O-2 consumption rates in the pathogen-treated shrimp, T-1 - T-9 (P < 0.05) indicate that these shrimp faced pathogenic stress. Shrimp in the control group showed 1.5-2 fold higher growth (increase in body weight) compared to treatment groups (T-1 - T-9). Results indicate that different doses of pathogenic exposure significantly altered the expression of candidate genes together with changes in physiological (O-2 consumption rates) and biochemical (hemocyte counts, glucose and serotonin levels of hemolymph) parameters that adversely affected growth and mortality of experimental shrimps.

关键词： Carbonic anhydrase   Cyclooxygenase   Acidosis   Shell hardness   Mussels   Marine pollution  

摘要： The increasing presence of anthropogenic contaminants in the environment may constitute a challenge to nontarget biota, considering that most contaminants can exert deleterious effects. Salicylic acid (SA) is a non-steroid anti-inflammatory drug (NSAID) which exerts its activity by inhibiting the enzyme cyclooxygenase (COX). Another class of drugs is that of the diuretics, in which acetazolamide (ACZ) is included. This pharmaceutical acts by inhibiting carbonic anhydrase (CA), a key enzyme in acid-base homeostasis, regulation of pH, being also responsible for the bio-availability of Ca2+ for shell biomineralization processes. In this work, we evaluated the chronic (28-day) ecotoxicological effects resulting from the exposures to SA and ACZ (alone, and in combination) on individuals of the marine mussel species Mytillus spp., using enzymatic (catalase (CAT), glutathione Stransferases (GSTs), COX and CA), non-enzymatic (lipid peroxidation, TBARS levels) and morphological and physiological (shell hardness, shell index and feeding behaviour) biomarkers. Exposure to ACZ and SA did not cause significant alterations in CAT and GSTs activities, and in TBARS levels. In terms of CA, this enzyme was inhibited by the highest concentration of ACZ in gills of exposed animals, but no effects occurred in the mantle tissue. The activity of COX was not altered after exposure to the single chemicals. However, animals exposed to the mixture of ACZ and SA evidenced a significant inhibition of COX activity. Morphological and physiological processes (namely, feeding, shell index, and shell hardness) were not affected by the here tested pharmaceutical drugs. Considering the general absence of adverse effects, further studies are needed to fully evaluate the effects of these pharmaceutical drugs on alternative biochemical and physiological pathways.

关键词： Ediblebird's nest   Extraction   Glycoconjugates   N-acetylneuraminic acid   Neuraminidase   Sialic acid  

摘要： Sialic acids are a group of nine-carbon alpha-keto acids. Sialic acid exists in more than 50 forms, with the natural types discovered as N-acetylneuraminic acid (Neu5Ac), deaminoneuraminic acid (2-keto-3-deoxy-nonulononic acid or Kdn), and N-glycolylneuraminic acid (Neu5Gc). Sialic acid level varies depending on the source, where edible bird's nest (EBN), predominantly Neu5Ac, is among the major sources of sialic acid. Due to its high nutritive value and complexity, sialic acid has been studied extensively through acid, aqueous, and enzymatic extraction. Although detection by chromatographic methods or mass spectrometry is common, the isolation and recovery work remained limited. Sialic acid is well-recognised for its bioactivities, including brain and cognition development, immune-enhancing, anti-hypertensive, anticancer, and skin whitening properties. Therefore, sialic acid can be used as a functional ingredient in the various industries. This paper reviews the current trend in the biochemistry, sources, extraction, and functions of sialic acids with special reference to EBN.

关键词： Difenoconazole   Hepatic toxicity   Transcriptomic analysis   Mice  

摘要： Difenoconazole (DFZ) is a broad-spectrum triazole fungicide, that is extensively used in agriculture. Studies have shown that residues of DFZ and other fungicides have toxic effects on nontarget organisms. However, its hepatoxicity in mammals remains unclear. Here, we characterized the toxic hepatic effects in male C57BL/6 mice exposed to 30 and 100 mg/kg bw DFZ for 14 and 56 days, respectively. The results revealed that DFZ could increase the relative liver weights, however, the relative fat and spleen weights decreased. More importantly, DFZ exposure changed the hepatic morphology and induced hepatic oxidative stress. Gene expression analysis suggested that DFZ could induce a glycolipid metabolism disorder. Moreover, hepatic transcriptomic analysis revealed the effects of DFZ exposure on the transcriptional levels of various genes, and enrichment analysis of differentially expressed genes (DEGs) showed that energy metabolism and immune-associated pathways were mainly affected. We validated the results from transcriptomic analysis and found that some key genes related to energy metabolism were affected. In addition, flow cytometry showed that the CD3+/CD4+ and CD3+ /CD8+ levels declined in the spleen of mice. Taken together, these findings combined with transcriptome analysis highlighted that DFZ caused different endpoints in the liver, which could provide more evidence for investigating the toxic effects of DFZ in mammals.

关键词： Biometry   Menthol anesthesia   "pacama"   Welfare  

摘要： Anesthesia is an indispensable procedure during the handling of fish. This work evaluated the effects of menthol as anesthetic for juvenile Lophiosilurus alexandri. Menthol concentrations of 0 (control), 25, 50, 150, 300 and 450 mg L-1 were tested using 14 animals for each concentration, with each fish being a replicate. Blood was sampled from seven of the juveniles in each group shortly after anesthetic induction and from the other seven at 24 h postanesthesia and procedures to collect biometric measures, i.e., handling and air exposure. Induction time showed a linear response plateau effect (LRP) with an inflection point of 142 mg L-1, while a dose-response relationship was observed among concentrations for recovery time. Ventilatory frequency (VF) during anesthetic induction had a LRP effect with an inflection point of 127 mg L-1, while during recovery it had a quadratic effect with a maximum point of 305.45 mg L-1. Fish anesthetized with 50 mg L-1 of menthol had the lowest hematocrit values (P < 0.05), while those exposed to 450 mg L-1 had the lowest erythrocyte values (P < 0.001). Other changes in hemato-biochemical parameters are discussed. Concentrations between 50 and 300 mg L-1 of menthol were able to induce deep anesthesia in juvenile L. alexandri with induction and recovery times considered ideal for fish. The use of 50 mg L-1 of menthol was able to reduce VF during induction and recovery and also prevent increased plasma glucose, with little influence on hematological and biochemical parameters after handling.