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Abstract Intermediate metabolism and oxidative balance markers help to better understand environmental dynamics and how they influence the physiological patterns of organisms. Procambarus clarkii (Girard, 1852), a crayfish native to the United States of America and Mexico, represents an appealing case study for understanding invasive species’ metabolic dynamics. This species has sexual dimorphism and two male morphotypes: reproductive (M1) and non-reproductive (M2). We evaluated the seasonal variations of biomarkers in M1 and M2 males, collected in each season of 2016 at Parque Alfredo Volpi (São Paulo, Brazil). Hemolymph, hepatopancreas and abdominal muscle samples were extracted to determine markers of intermediate metabolism, oxidative balance, the hepatosomatic index and the stomach repletion degree. The results showed differences between the two male morphotypes. M1 showed a predominance of medium to full stomachs throughout the year, with an allocation of energetic substrates mainly used in reproduction (gametogenesis and reproductive behaviors). They also presented increased lipoperoxidation, SOD and GST activities. M2, on the other hand, had a lower capacity to allocate energy reserves in the period leading up to and during reproduction, which may be associated with a lower degree of gastric repletion. However, M2 maintained alternating antioxidant strategies that helped preserve low levels of lipoperoxidation in the hepatopancreas throughout the year. This pattern observed for the degree of gastric repletion indicates an intraspecific competition between the categories of males, which, together with the profile of energy reserve usage, seems decisive for M2 to reproduce.

The objectives of this study were to evaluate the ecophysiological state of the biota using a set of biomarkers in the upper-middle Luján River. To this aim, we collected adult Cnesterodon decemmaculatus fish, biofilm and water at three sampling sites in the upper-middle Luján River (S1: rural area, S2: Luján City and S3: urban area after passing Lujan City). For each site we determined physicochemical variables, heavy metal concentration in water, 19 biomarkers in fish (morphometric, histological, genotoxic, oxidative stress, metabolic and neurotoxic) and six biomarkers in biofilm (oxidative stress and extracellular enzyme). Additionally, we compared the responses of fish and biofilm with those of laboratory controls obtained from outdoor cultures. Our results indicated increased heavy metal concentration at all sites, mainly As and Cd, and decreased dissolved oxygen at S1 and S3. In fish, genotoxic biomarkers showed significant differences with respect to the control. The comet assay indicated damage in fish at the urbanized sites (S2 and S3) and an increased frequency of erythrocytes with nuclear aberrations at all sites. The CEA index (cellular energy allocation), calculated from the metabolic biomarkers and lipid concentration were significantly increased at S1. The gill damage evaluated histologically and with three indices indicated severe damage at all sites. Gills showed thickened primary and secondary lamellae and fusion of filaments at all sites, but a significant increase in mucous cells was only found at S1 and S3. Biofilm showed increased values of extracellular enzymes (β-glucosidase and alkaline phosphatase, lipid peroxidation and oxidative stress enzymes (i.e., catalase) at S3. These results are novel in that they incorporated laboratory controls allowing for comparisons with fish and biofilm from the field. They provided information on the status of a fish population and biofilm community, indicating the negative effect of river water deterioration on the tested organisms. Moreover, results showed what biomarkers were most sensitive for each biological sample. [Display omitted] • Lujan River showed increased concentrations of heavy metals (As, Cd). • Biomarkers in fish indicate genotoxic damage and oxidative stress in the urban area. • Histological indices indicated reduced gill surface for gas exchange at all sites. • Higher CEA and lipid content in rural area fish implied increased energy reserves. • The activity of oxidative stress enzymes in biofilm suggests environmental adaptation. [ABSTRACT FROM AUTHOR]

Alkaline pH can induce triacylglyceride accumulation in microalgae, however its molecular mechanism remains elusive. Here, we investigated the effect of 2-[N-cyclohexylamino]-ethane-sulfonic acid (CHES) -induced intracellular alkalization on the lipid production in Phaeodactylum tricornutum. Intracellular pH was increased upon CHES treatment, displaying a high BCECF fluorescence ratio. CHES treatment significantly induced lipid accumulation but had no change in cell density and biomass. The expression of genes involved in photoreaction, carbon fixation, glycolysis, pentose phosphate pathway, amino acid catabolism, GS/GOGAT cycle, TCA cycle, triacylglyceride assembly, de novo fatty acid synthesis were up-regulated, while that in amino acid biosynthesis were down-regulated under CHES conditions. Correspondingly, the activity of phosphoribulokinase, carbonic anhydrase, pyruvate dehydrogenase and acetaldehyde dehydrogenase were enhanced by CHES treatment. Chloroplast-specific biological processes were activated by CHES treatment in P. tricornutum, which redirects the flux of carbon into lipid biosynthesis, meanwhile stimulates de novo fatty acid biosynthesis, leading to lipid accumulation under CHES conditions. These indicate an enhancement of intermediate metabolism, resulting in lipid accumulation by CHES. [ABSTRACT FROM AUTHOR]

Background and Objectives The effects of plant growth-promoting activities involving biological, chemical, and organic fertilizers are partly well studied for pest insects. Still, studies concentrating on the impacts of such treatments on predators are uncommon. Plant growth promoting treatments- biological, -organic and -chemical fertilizers alter the biochemical composition of plants, which can impact the multitrophic interactions. Beneficial soil microorganisms such as plant growthpromoting rhizobacteria (PGPR) can affect nutritional quality, secondary metabolites, enzymes, phytohormones, and volatile organic compounds (VOCs) of plants, which may influence host plant-insect herbivore- natural enemies interactions. The predatory ladybird, Adalia bipunctata, is polyphagous species that mainly feed on aphids, especially the green peach aphid, Myzus persicae. It is a polyphagous insect that can cause damage to a lot of crops in fields and greenhouses. There is no published research concerning the effects of various plant growth-promoting on physiological performance of A. bipunctata. Thus, we investigated the impacts of various plant growth promoting treatments, viz. no fertilizer (untreated control), one type of PGPRs, vermicompost 30% (v/v), and zinc sulfate on physiological performance of A. bipunctata through M. persicae reared on treated Capsicum annum L. (Solanaceae). Materials and Methods Bell pepper seeds of the California Wonder cultivar were developed in 3L plastic pots and were used in bioassays when they reached 4-6 leaf stage under greenhouse conditions. Then, aphids were obtained from tomato farms from Meshkin-Shahr (Ardabil, Iran) and transmitted to bell pepper grown in the greenhouse. To keep an appropriate sub-sucking colony, every week the individuals were transferred from infested bell peppers to fresh plants. Adults of A. bipunctata were obtained from alfalfa farms of Ardabil, Iran, and transmitted to the laboratory, in a growth chamber. Mating pairs were selected and kept together in separate plastic jars (6 by 12 cm2) and were reared on pepper plants infested with sub-sucking insects as prey. In the study, the effect of spraying zinc sulfate on bell pepper plants and addition of the organic fertilizer of vermicompost 30% and the biologic fertilizers of Bacillus subtilis to the growing medium of bell pepper on the activities of critical physiological processes of A. bipunctata fed on M. persicae using a completely randomized design under greenhouse conditions. Then 5 adult predators were randomly selected from each treatment and homogenized with a hand pounder in 1 mL pure ice-cold water. After that, the specimens were centrifuged at 13,000 g pending 15 min at 4 ◦C. The top layer was collected and kept at 20 ◦C during biochemical analyses. All physiological enzymes assay based on the defined method were conduted in three biological replications. Then, data were analyzed using a one-way analysis of variance (ANOVA) followed by the Tukey test with the MINITAB software. Results The results demonstrated a significant difference among the digestive enzymes activities, intermediates, and storage compounds of the predatory ladybug reared on aphids fed on bell peppers treated with different fertilizers. The lowest total protease activity of ladybird was observed in the control compared to other treatments. The elastase activity of ladybug increased on B. subtilis compared to other treatments. The highest and lowest amounts of cathepsin B activity in ladybugs were recorded on B. subtilis and vermicompost 30%, respectively. The highest and lowest low density lipophore (LDL) values were observed in A. bipunctata on control and B. subtilis treatment, respectively. Predatory ladybug had the highest protein, triglyceride, and glycogen on B. subtilis compared to other treatments. The lowest triglyceride and glycogen was also observed on vermicompost 30%. Discussion Plant-herbivore interactions under the influence of bio-fertilizer have led to increased digestive enzymes activity and storage compounds in ladybug, which could be used in combination with the use of biological control agents in integrated management programs of the green peach aphid in greenhouses. [ABSTRACT FROM AUTHOR]

Bivalves are among the marine organisms most influenced by climate change. Despite the flat oyster's Ostrea edulis high economic value, its culture is developed on a very small scale, since this species possesses a strong susceptibility to abiotic stressors. Due to climate change, temperature is one of the most critical environmental parameters for the welfare of the Mediterranean basin's marine inhabitants. The present study's purpose was to investigate the physiological performance of the Mediterranean's native O. edulis as it faces exposure to different temperatures. Since juveniles are more susceptible to abiotic stressors, this experimental procedure was focused on young individuals. The seawater temperatures studied included a standard control temperature of 21 °C (often observed in several marine areas throughout the Mediterranean), as well as increased seawater temperatures of 25 °C and 28 °C, occasionally occurring in shallow Mediterranean waters inhabited by bivalve spat. These were selected since the tissues of O. edulis becomes partly anaerobic in temperatures exceeding 26 °C, while cardiac dysfunction (arrhythmia) emerges at 28 °C. The results demonstrate that temperatures above 25 °C trigger both the transcriptional upregulation of hsp70 and hsp90, and the antioxidant genes Cu/Zn sod and catalase. Enhancement of thermal tolerance and increased defense against increased ROS production during thermal stress, were observed. As the intensity and duration of thermal stress increases, apoptotic damage may also occur. The increased oxidative and thermal stress incurred at the highest temperature of 28 °C, seemed to trigger the switch from aerobic to anaerobic metabolism, reflected by higher pepck mRNA expressions and lower ETS activity. [Display omitted] • Ostrea edulis response to elevated temperature was evaluated. • Increased temperature leads to thermal, oxidative and metabolic stress response. • In the critical threshold above 28 °C of seawater, oysters switch to anaerobiosis. • Thermal tolerance of oysters is a necessary parameter for aquaculture development. • Hsp, Cu/Zn sod, cat, bax, pepck genes first characterization in O. edulis. [ABSTRACT FROM AUTHOR]

Melanophryniscus admirabilis is a frog endemic to the southern Atlantic Forest (Brazil), with restricted distribution and considered as critically endangered. The aim of this study was to evaluate possible alterations in biomarkers of metabolism (glycogen, proteins, and uric acid) and oxidative balance (superoxide dismutase, catalase, glutathione S-transferase, and lipoperoxidation) of tadpoles of Melanophryniscus admirabilis exposed to commercial herbicide formulations containing sulfentrazone (Boral® 500 SC: 130 and 980 μg a.i./L) and glyphosate (Roundup® Original: 234 and 2340 μg a.i./L). Mortality was not observed in any of the groups studied. Our results show that a 96-h exposure to the herbicides decreased glycogen levels, indicating increased energy demand for xenobiotic metabolism. Protein levels increased in the Boral group but decreased in the higher concentration of Roundup, and uric acid levels did not change significantly between the experimental groups. Lipoperoxidation decreased in the Boral group and in the higher concentration of Roundup. Decreased levels of superoxide dismutase in both treatments and of catalase in the lowest concentration of the herbicides were observed. Glutathione S-transferase activity increased in the Roundup group; this enzyme seems to be crucial in the metabolization of the herbicides and in the survival of the tadpoles. Our results suggest that M. admirabilis has a high antioxidant capacity, which guaranteed the survival of tadpoles. Nevertheless, exposure to pesticides could impose a serious risk to this species, especially considering its restricted distribution, habitat specificity, and high physiological demand to metabolize xenobiotics. [ABSTRACT FROM AUTHOR]

is a freshwater crayfish native to the southern central United States and northern Mexico. In Brazil, it is only present in natural environment in the state of São Paulo. Nutritional and reproductive markers were quantified and characterized, as well as intermediate metabolism and oxidative balance in females of P. clarkii collected in a natural environment over a seasonal cycle. Samples of hemolymph and different tissue were obtained. The degree of gastric repletion presented the highest rates in the spring. An investment in reproduction was detected in the summer, when the energy reserves of the hepatopancreas were mobilized for gonadal maturation, and a higher percentage of mature gonads were observed. In the same period, we observed an increase in lipoperoxidation, despite the increased activity of superoxide dismutase and glutathione S-transferase in muscle and gonads. An increase in the levels of lipoperoxidation and glutathione S-transferase was observed in winter. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify the effects of the isolated forms of Boral® SC 500, Glifosato® Biocarb herbicides, and a blend of both herbicides on metabolism and oxidative balance markers of Rana catesbeiana tadpoles and on their nutritional condition. Groups of tadpoles were divided into different treatments: control (no herbicides), Boral® 500 SC (sulfentrazone: 130 μg/L), Glifosato® Biocarb (glyphosate: 234 μg/L), and a blend of both herbicides. After 7 days, the liver, caudal muscle, and blood samples were taken to subsequently perform the biomarkers determination by spectrophotometry. The intestinal condition factor increased in animals exposed to glyphosate and herbicide blends, suggesting a hyperphagic effect. This hypothesis was confirmed by the rise of triglycerides and circulating very low–density lipoprotein (VLDL). There was a significant increase in the levels of uric acid in tadpoles exposed to the herbicide blend. Corticosterone levels reduced significantly in animals exposed to glyphosate and the herbicide blend. Oxidative stress markers had a tissue-dependent response. In the liver, glutathione S-transferase increased, and superoxide dismutase and catalase decreased in animals exposed to sulfentrazone and glyphosate. Lipoperoxidation was reduced in the glyphosate treatment. In the caudal muscle, superoxide dismutase and catalase activities were maintained, and there was a decline in the levels of glutathione S-transferase and TBARS only in the blend group. [ABSTRACT FROM AUTHOR]

This reviewsystematically examines the evidence for shifts in flux through energy generating biochemical pathways in Huntington's disease (HD) brains from humans and model systems. Compromise of the electron transport chain (ETC) appears not to be the primary or earliest metabolic change in HD pathogenesis. Rather, compromise of glucose uptake facilitates glucose flux through glycolysis and may possibly decrease flux through the pentose phosphate pathway (PPP), limiting subsequent NADPH and GSH production needed for antioxidant protection. As a result, oxidative damage to key glycolytic and tricarboxylic acid (TCA) cycle enzymes further restricts energy production so that while basal needs may be met through oxidative phosphorylation, those of excessive stimulation cannot. Energy production may also be compromised by deficits in mitochondrial biogenesis, dynamics or trafficking. Restrictions on energy production may be compensated for by glutamate oxidation and/or stimulation of fatty acid oxidation. Transcriptional dysregulation generated by mutant huntingtin also contributes to energetic disruption at specific enzymatic steps. Many of the alterations in metabolic substrates and enzymes may derive from normal regulatory feedback mechanisms and appear oscillatory. Fine temporal sequencing of the shifts in metabolic flux and transcriptional and expression changes associated with mutant huntingtin expression remain largely unexplored and may be model dependent. Differences in disease progression among HD model systems at the time of experimentation and their varying states of metabolic compensation may explain conflicting reports in the literature. Progressive shifts in metabolic flux represent homeostatic compensatory mechanisms that maintain the model organism through presymptomatic and symptomatic stages. [ABSTRACT FROM AUTHOR]

The inhibitor NU 2058 [6-(cyclohexylmethoxy)-9H-purin-2-amine] leads to G1-phase cell cycle arrest in the marine diatom, Phaeodactylum tricornutum, by binding to two cyclin-dependent kinases, CDKA1 and CDKA2. NU 2058 has no effect on photosynthetic attributes, such as Fv/Fm, chlorophyll a/cell, levels of D2 PSII subunits, or RbcL; however, cell cycle arrest leads to unbalanced growth whereby photosynthetic products that can no longer be used for cell division are redirected toward carbohydrates and triacylglycerols (TAGs). Arrested cells up-regulate most genes involved in fatty acid synthesis, including acetyl-CoA carboxylase, and three out of five putative type II diglyceride acyltransferases (DGATs), the enzymes that catalyze TAG production. Correlation of transcriptomes in arrested cells with a flux balance model for P. tricornutum predicts that reactions in the mitochondrion that supply glycerate may support TAG synthesis. Our results reveal that sources of intermediate metabolites and macromolecular sinks are tightly coupled to the cell cycle in a marine diatom, and that arresting cells in the G1 phase leads to remodeling of intermediate metabolism and unbalanced growth. [ABSTRACT FROM AUTHOR]

The toxicological effect of cellular extract of cyanobacterium Radiocystis fernandoi strain R28 containing RR and YR microcystins was analyzed in the fish Hoplias malabaricus with emphasis on the liver structure and energetic metabolism, after short-term exposure. Fish were intraperitoneally (i.p.) injected with 100 μg of equivalent MC-LR kg −1 body mass containing in the cellular extract of R. fernandoi strain R28. Twelve and 96 h post-injection, the plasma, liver and white muscle were sampled for biochemical analyses and liver was also sampled for morphological analyses. After i.p. injection, the activity of acid phosphatase (ACP), alanine aminotransferase (ALT) and direct bilirubin increased in the plasma, while ALT and aspartate aminotransferase (AST) decreased in the liver. Glucose, lactate and pyruvate increased while protein decreased in the plasma; glycogen, pyruvate and lactate decreased in the liver; and glycogen and glucose increased in the muscle. Ammonia increased in the plasma, liver and muscle. The hepatocyte cell shape changed from polyhedral to round after cellular extract injection; there was loss of biliary canaliculus organization, but the biliary duct morphology was conserved in the liver parenchyma. In conclusion, microcystins present in the cellular extract of R. fernandoi strain R28 affect the liver structure of H. malabaricus , but the liver was able to continuously produce energy by adjusting its intermediate metabolism; glycogenolysis and gluconeogenesis maintained glucose homeostasis and energy supply. [ABSTRACT FROM AUTHOR]

The effect of feed restriction on gene expression of regulatory enzymes of intermediary metabolism was studied in two sheep breeds (Australian Merino and Dorper) subjected to two nutritional treatments: feed restriction (85% of daily maintenance requirements) and control (ad libitum feeding), during 42 days. The experimental animals (ram lambs) were divided into four groups, n = 5 (Australian Merino control (MC), Australian Merino Restriction (MR), Dorper control (DC) and Dorper Restriction (DR)). After the trial, animals were sacrificed and samples were taken from liver tissue to quantify glucose levels and gene expression of relevant intermediary metabolism enzymes (phosphofructokinase (PFK), pyruvate kinase (PK), phosphoenolpyruvate carboxykinase, fructose 1,6-bisphosphatase, glucose-6-phosphatase, glycogen synthase (GS), fatty acid synthase (FAS), glutamate dehydrogenase (GDH) and carbamoyl phosphate synthase (CPS)) through real-time PCR. During the experimental period, the MR animals lost 12.6% in BW compared with 5.3% lost by the Dorper lambs. MC and DC rams gained, respectively, 8.8% and 14% during the same period. Within the Dorper breed, restricted feed animals revealed a significant decrease over controls in the transcription of PFK (1.95-fold) and PK (2.26-fold), both glycolytic enzymes. The gluconeogenesis showed no change in the feed restricted animals of both breeds. DR feed group presented a significant decrease over the homologous Merino sheep group on GS. In both experimental breeds, FAS mRNA expression was decreased in restricted feed groups. GDH expression was decreased only in the DR animals (1.84-fold) indicating a reduced catabolism of amino acids in these animals. Finally, CPS was significantly (P < 0.05) higher in the Dorper sheep, indicating a facilitated urea synthesis in this breed. These results indicate a better adaptation of metabolic intermediate regulatory enzymes and hepatic glucose production of Dorper sheep to feed restriction concurring with the BW results in the experimental groups.

This work aims at the identification of relevant intermediate metabolism enzymes contributing to improved meat production due to genetic selection. A wild rabbit (WR) breed and a highly meat selected breed (New Zealand (NZ) rabbit) were used. Food restriction was used as an experimental condition so as to enhance differences within the metabolic pathways under study. During a period of 30 days, NZ and WR experimental breeds were subjected to, respectively, 40% and 60% ad libitum food restriction leading to 17.7% and 21.1% initial weight. Hepatic glycolytic, lipidic and protein regulatory enzyme activity, transcriptional and metabolite levels were determined. Insulin-like growth factor (IGF-1), triiodothyronine, and cortisol were also evaluated. In the glycolytic pathways, the NZ control rabbits presented a higher phosphofructokinase and pyruvate kinase activity level when compared to the WR, while the latter group showed a higher expression of glycogen synthase, although with less glycogen content. In the nitrogen metabolism, our results showed a lower activity level of glutamate dehydrogenase in WR when subjected to food restriction. Within the lipid metabolism, results showed that although WR had a significantly higher mRNA hepatic lipase, non-esterified fatty acid levels were similar between the experimental groups. NZ rabbits presented a better glycemia control and greater energy substrate availability leading to enhanced productivities in which triiodothyronine and IGF-1 played a relevant role.

Diatoms (Bacillarophyceae) are photosynthetic unicellular microalgae that have risen to ecological prominence in oceans over the past 30 million years. They are of interest as potential feedstocks for sustainable biofuels. Maximizing production of these feedstocks will require genetic modifications and an understanding of algal metabolism. These processes may benefit from genome-scale models, which predict intracellular fluxes and theoretical yields, as well as the viability of knockout and knock-in transformants. Here we present a genome-scale metabolic model of a fully sequenced and transformable diatom: Phaeodactylum tricornutum. The metabolic network was constructed using the P. tricornutum genome, biochemical literature, and online bioinformatic databases. Intracellular fluxes in P. tricornutum were calculated for autotrophic, mixotrophic and heterotrophic growth conditions, as well as knockout conditions that explore the in silico role of glycolytic enzymes in the mitochondrion. The flux distribution for lower glycolysis in the mitochondrion depended on which transporters for TCA cycle metabolites were included in the model. The growth rate predictions were validated against experimental data obtained using chemostats. Two published studies on this organism were used to validate model predictions for cyclic electron flow under autotrophic conditions, and fluxes through the phosphoketolase, glycine and serine synthesis pathways under mixotrophic conditions. Several gaps in annotation were also identified. The model also explored unusual features of diatom metabolism, such as the presence of lower glycolysis pathways in the mitochondrion, as well as differences between P. tricornutum and other photosynthetic organisms. [ABSTRACT FROM AUTHOR]

The effect of feed restriction on gene expression of regulatory enzymes of intermediary metabolism was studied in two sheep breeds (Australian Merino and Dorper) subjected to two nutritional treatments: feed restriction (85% of daily maintenance requirements) and control (ad libitum feeding), during 42 days. The experimental animals (ram lambs) were divided into four groups, n = 5 (Australian Merino control (MC), Australian Merino Restriction (MR), Dorper control (DC) and Dorper Restriction (DR)). After the trial, animals were sacrificed and samples were taken from liver tissue to quantify glucose levels and gene expression of relevant intermediary metabolism enzymes (phosphofructokinase (PFK), pyruvate kinase (PK), phosphoenolpyruvate carboxykinase, fructose 1,6-bisphosphatase, glucose-6-phosphatase, glycogen synthase (GS), fatty acid synthase (FAS), glutamate dehydrogenase (GDH) and carbamoyl phosphate synthase (CPS)) through real-time PCR. During the experimental period, the MR animals lost 12.6% in BW compared with 5.3% lost by the Dorper lambs. MC and DC rams gained, respectively, 8.8% and 14% during the same period. Within the Dorper breed, restricted feed animals revealed a significant decrease over controls in the transcription of PFK (1.95-fold) and PK (2.26-fold), both glycolytic enzymes. The gluconeogenesis showed no change in the feed restricted animals of both breeds. DR feed group presented a significant decrease over the homologous Merino sheep group on GS. In both experimental breeds, FAS mRNA expression was decreased in restricted feed groups. GDH expression was decreased only in the DR animals (1.84-fold) indicating a reduced catabolism of amino acids in these animals. Finally, CPS was significantly (P < 0.05) higher in the Dorper sheep, indicating a facilitated urea synthesis in this breed. These results indicate a better adaptation of metabolic intermediate regulatory enzymes and hepatic glucose production of Dorper sheep to feed restriction concurring with the BW results in the experimental groups. [ABSTRACT FROM PUBLISHER]

Alkaline pH can induce triacylglyceride accumulation in microalgae, however its molecular mechanism remains elusive. Here, we investigated the effect of 2-[N-cyclohexylamino]-ethane-sulfonic acid (CHES) -induced intracellular alkalization on the lipid production in Phaeodactylum tricornutum . Intracellular pH was increased upon CHES treatment, displaying a high BCECF fluorescence ratio. CHES treatment significantly induced lipid accumulation but had no change in cell density and biomass. The expression of genes involved in photoreaction, carbon fixation, glycolysis, pentose phosphate pathway, amino acid catabolism, GS/GOGAT cycle, TCA cycle, triacylglyceride assembly, de novo fatty acid synthesis were up-regulated, while that in amino acid biosynthesis were down-regulated under CHES conditions. Correspondingly, the activity of phosphoribulokinase, carbonic anhydrase, pyruvate dehydrogenase and acetaldehyde dehydrogenase were enhanced by CHES treatment. Chloroplast-specific biological processes were activated by CHES treatment in P. tricornutum , which redirects the flux of carbon into lipid biosynthesis, meanwhile stimulates de novo fatty acid biosynthesis, leading to lipid accumulation under CHES conditions. These indicate an enhancement of intermediate metabolism, resulting in lipid accumulation by CHES., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liu, Yin, Zhang, Xie, Dong, Lu, Tao, Gong, Chen, Shi, Qin, Zeng, Li, Li, Zhao and Zhang.)

We compared the effect of different diets biochemical composition, levels of lipid peroxidation, survival rate, and reproductive aspects of Hyalella pleoacuta and H. curvispina. These crustaceans live in limnetic environments of the plateau and coastal plain, respectively, in southern Brazil. In the laboratory, the animals were kept in aquariums under controlled conditions and fed ad libitum, for 30 days with different diets. Macrophyte only (MO) mimicked a caloric restriction in both species and sexes, because they showed depletion of glycogen and proteins, this fact was reinforced by the decrease in the levels of lipoperoxidation. These responses were probably a result of the low caloric input. In the animals that received macrophyte plus commercial food (MCF) these responses were reversed when the energy reserves were maintained and the levels of lipoperoxidation were higher than those of animal that received MO. Animals fed on MCF showed more activity, higher numbers of couples, ovigerous females and eggs for females, however, the rate of survival was similar in both diets. The caloric requirements of both species were probable supplied with MCF, which provided more carbohydrates, proteins and lipids, and this diet provided valuable information concerning adequate maintenance of the animals for toxicology experiments, and principally increases the knowledge about the physiology of this genus. [ABSTRACT FROM AUTHOR]

Roundup (glyphosate formulation) is a nonselective and posts emergent herbicide used for controlling aquatic weeds and different concentrations are used in cultures around the world. The objective of this investigation was to examine the effects of Roundup (glyphosate formulation) on the biochemical composition, levels of lipoperoxidation, Na/KATPase activity and reproductive traits in the Hyalella castroi. Amphipods were collected in summer 2009, in the southern Brazilian highlands. In the laboratory, the animals were kept in aquariums under controlled conditions for 7 days, and after this period they were exposed to 0.36, 0.52, 1.08 and 2.16 mg/l of glyphosate for 7 days. After the period of exposure, the animals were immediately frozen for determination of glycogen, proteins, lipids, triglycerides, cholesterol, levels of lipoperoxidation, and Na/KATPase activity. During each day of the cultivation reproductive traits (number of reproductive pairs, ovigerous females and eggs in the marsupium) were observed. All concentrations of Roundup induced significant decreases in all biochemical parameters and Na/KATPase activity, and significant increase in lipoperoxidation levels. Showing this form a potentially toxic effect at very low concentrations, this pattern of results can lead to significant changes in trophic structure of limnic environments because these amphipods are important links in food chain in these habitats. [ABSTRACT FROM AUTHOR]

We compared the effect of different diets in the biochemical composition, levels of lipoperoxidation and survival rates of males and females of Hyalella bonariensis. These crustaceans live in limnetic environments and different kinds of food habits are present in the genus Hyalella. Adult animals were collected in the spring (September) in a stream near to Salto city, Buenos Aires. In the laboratory, the animals were kept submerged in aquariums, separated by sex, under controlled conditions and survive rates were observed. They were fed ad libitum for 45 days with four different diets, and after this period the animals were used for biochemical determinations. Statistical analysis revealed significant differences in the responses to glycogen, proteins, lipids, triglycerides and lipoperoxidation levels in both sexes of these amphipods taken from the natural environment. Animals that received macrophytes associated a ration with high content of proteins (43%) during 45 days presented the major survival rates (males= 86.6% and females= 96.6%). These responses can be revealed that this specie primarily feeding macrophytes associated with deposit feeder, and that this diet is more generalized. This study showed the importance of the proteins in diet of this amphipod, were the females increased the reserves of proteins and triglycerides with different diets probably for reproductive events and male increased the reserves of glycogen and triglycerides for reproductive events and growth. [ABSTRACT FROM AUTHOR]

The Ames dwarf mouse is well known for its remarkable propensity to delay the onset of aging. Although significant advances have been made demonstrating that this aging phenotype results primarily from an endocrine imbalance, the post-transcriptional regulation of gene expression and its impact on longevity remains to be explored. Towards this end, we present the first comprehensive study by microRNA (miRNA) microarray screening to identify dwarf-specific lead miRNAs, and investigate their roles as pivotal molecular regulators directing the long-lived phenotype. Mapping the signature miRNAs to the inversely expressed putative target genes, followed by in situ immunohistochemical staining and in vitro correlation assays, reveals that dwarf mice post-transcriptionally regulate key proteins of intermediate metabolism, most importantly the biosynthetic pathway involving ornithine decarboxylase and spermidine synthase. Functional assays using 3′-untranslated region reporter constructs in co-transfection experiments confirm that miRNA-27a indeed suppresses the expression of both of these proteins, marking them as probable targets of this miRNA in vivo. Moreover, the putative repressed action of this miRNA on ornithine decarboxylase is identified in dwarf mouse liver as early as 2 months of age. Taken together, our results show that among the altered aspects of intermediate metabolism detected in the dwarf mouse liver – glutathione metabolism, the urea cycle and polyamine biosynthesis – miRNA-27a is a key post-transcriptional control. Furthermore, compared to its normal siblings, the dwarf mouse exhibits a head start in regulating these pathways to control their normality, which may ultimately contribute to its extended healthspan and longevity. [ABSTRACT FROM AUTHOR]

Abstract: As the molecular mechanisms associated with aging become more understood, it is apparent that the normal processes involved in the development and metabolism of an organism are subject to changes that upset its crucial homeostatic balance, which in turn sets in motion the weakening and disease-prone process of senescence. This imbalance is the result of a variety of effectors, such as environmental insults, endogenous toxins, and genetic mishaps. In addition, it is highly probable that posttranscriptional regulatory events play a large role in the changes associated with aging. The emerging knowledge of posttranscriptional regulation is redefining our understanding of the complexities of cellular systems biology and genetics. The implications of the impact that small regulatory RNAs have on the many facets of developmental and molecular biology should be included as part of our current understanding of the biochemistry involved in these processes. These molecular regulators—along with other epigenetic events—restrict the flow of genetic expression, thus affording the cell an adjustable and tempered homeostatic balance control. Recent findings in the fields of organismal development, cancer, and aging indicate that small noncoding RNA plays a greater role than previously believed in orchestrating the changes associated with these processes. Furthermore, any misappropriations of these regulatory resources could lead to age-related diseases, and are therefore promising targets for prophylactics and therapeutics to combat maladies associated with aging. Here we report a brief overview of noncoding RNA as well as the potential roles of microRNAs in biochemical equilibriums where imbalance contributes to the many phenotypes of aging. [Copyright &y& Elsevier]

Abstract: Continuous or pulse exposure to pesticides may have negative effects on non-target organisms, resulting in a number of pathological and disturbed biochemical processes, including changes in energy budgets. The objective of this investigation was to examine the potential effects of carbofuran on the biochemical composition (glycogen, proteins, total lipids, triglycerides and cholesterol), levels of lipoperoxidation, Na+/K+ATPase activity, and reproductive behaviors (number of reproductive pairs, ovigerous females, and number of eggs) in the amphipod Hyalella castroi. The amphipods were collected in spring 2007, in the southern Brazilian highlands. In the laboratory, the animals were kept in aquariums under controlled conditions for 7 days, and after this period were exposed to 1 or 10 µg/L of carbofuran for 7 days. After the period of exposure, the animals were immediately frozen for determination of glycogen, proteins, lipids, triglycerides, total cholesterol, levels of lipoperoxidation, and Na+/K+ATPase activity. During each day of culture, reproductive behaviors were observed. Carbofuran induced significant decreases in biochemical reserves (glycogen, proteins, lipids, triglycerides and cholesterol), a significant increase in lipoperoxidation levels, and a decrease in Na+/K+ATPase activity in both males and females. Studies of all the biochemical parameters seem to be quite promising, in order to assess and predict the effects of toxicants on non-target organisms. The results showed that reproductive behaviors may provide sensitive criteria for assessing ecotoxicological effects. H. castroi lives among rooted aquatic macrophytes, and we suggest that it is a sensitive species that could be used in monitoring studies. [Copyright &y& Elsevier]

Abstract: The present study investigated the effects of carbofuran on the energy metabolism (levels of glycogen, total proteins, total lipids, triglycerides, and lipoperoxidation), Na+/K+ATPase activity, and reproductive parameters (formation of couples, ovigerous females, and mean number of eggs) in the freshwater amphipods Hyalella pleoacuta and Hyalella curvispina. These crustaceans live in limnetic environments of the plateau (H. pleoacuta) and coastal plain (H. curvispina) of the state of Rio Grande do Sul in southern Brazil. The animals were collected in the winter of 2006 in the Vale das Trutas (28°47′00″S–49°50′53″W) in the Municipality of São José dos Ausentes, and in Gentil Lagoon (29°56′30″S, 50°07′50″W) in the Municipality of Tramandaí. In the laboratory, the amphipods were kept submerged in aquariums under controlled conditions of photoperiod (12 h light: 12 h dark), temperature (23 °C±1), and constant oxygenation. Animals were exposed to carbofuran at a dose of 5 or 50 μg/L for a period of 7 days. At the end of this period, the animals were immediately frozen for determination of the biochemical parameters, lipoperoxidation levels (TBARS), and enzyme Na+/K+ATPase activity. During each day of culture, several reproductive parameters were observed. Statistical analysis (ANOVA) revealed that carbofuran induces significant decreases in glycogen, proteins, lipids, triglycerides, and Na+/K+ATPase, as well as a significant increase in lipoperoxidation levels. Studies of all the biochemical parameters seem to be quite promising, in order to assess and predict the effects of toxicants on non-target organisms. The results also suggest that the reproductive parameters (formation of couples, ovigerous females and mean number of eggs) may provide sensitive criteria for assessing ecotoxicological effects. Furthermore, H. pleoacuta and H. curvispina are suitable organisms for use in toxicity tests, and we suggest that they are sensitive species that could be used in monitoring studies. [Copyright &y& Elsevier]

The experiments were conducted on two yearling moose (Alces alces) with rumen fistulas in July and October. Intake of digestible nutrients and energy was two times higher in July than in October when water balance was lower. Total volatile fatty acid concentration in rumen liquid decreased with a proportional change of increased acetate and reduced propionate and butyrate. Coincidentally, the level of volatile fatty acids in blood rose, and glucose and concentration of ketone bodies declined. The data suggest that metabolic adaptations for limiting heat loss in winter include inhibition of aerobic oxidation, enhancement of anaerobic glycolytic pathways of energy supply, and reduction of water exchange. [ABSTRACT FROM AUTHOR]

Seasonal collections of the subtidal horse mussel, Modiolus modiolus, from a depth of 10 m were made at the Isles of Shoals, New Hampshire to assess changes in overall energetic demand, measured as respiration, the maximal activities of rate-limiting enzymes of intermediate metabolism, level of oxidative stress, and the expression of heat shock proteins (HSP). Weighted respiration rates of mussels from winter collections were significantly lower than summer rates but decreased by less than 20%. Specific activities of several rate-limiting enzymes were measured in mussels from the summer and winter collections at the temperature of collection and the reciprocal seasonal temperature (15 and 5 °C). Comparisons of these enzyme activities and the protein concentrations of hexokinase and citrate synthase show that a quantitative strategy is used to acclimatize to winter temperatures by these rate-limiting enzymes of intermediate metabolism. The activities and protein concentrations of the antioxidant enzyme, Cu/Zn superoxide dismutase (SOD) is seasonally indistinguishable while the concentration of HSP 70 was greater in winter than in summer samples. These results show that mussels seasonally compensate for decreases in temperature by increasing the concentration of rate-limiting metabolic enzymes while maintaining the same level of antioxidant protection in summer and winter consistent with high aerobic metabolism in both winter and summer. Lastly, the significantly greater concentrations of HSP70 in winter samples suggests that protein chaperone functions must be maintained while other seasonal adjustments to cold temperatures are occurring. [Copyright &y& Elsevier]

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In this study we investigated the presence of short-chain acyl-CoA hydrolases in rat liver mitochondria. One acetyl-CoA-hydrolyzing enzyme with a molecular mass of about 48 kDa was purified to apparent homogeneity as judged by SDS/PAGE. Immunoprecipitation experiments with antibodies raised to the purified protein showed that this enzyme corresponds to a minor portion of the total mitochondrial acetyl-CoA hydrolase activity, most (about 90%) of the total activity being due to an enzyme which was labile and required Triton X-100 for its stability. Neither of these acetyl-CoA-hydrolyzing enzymes appeared to be induced by treatment of rats with di(2-ethylhexyl)phthalate, a peroxisome proliferator which mediates induction of several cytosolic and mitochondrial long-chain acyl-CoA thioesterases. In addition, an enzyme that hydrolyzed acetoacetyl-CoA was partially purified; it was induced about 3.5-fold by di(2-ethylhexyl)phthalate treatment. In conclusion, these results demonstrate that rat liver mitochondria contain several enzymes capable of hydrolyzing short-chain acyl-CoA, indicating that regulation of the metabolism of short-chain acyl-CoAs and formation of ketone bodies, could be complex. [ABSTRACT FROM AUTHOR]