Hepatic transcriptomic analysis reveals differential regulation of metabolic and immune pathways in three strains of chickens with distinct growth rates exposed to mixed parasite infections.

During parasite infections, the liver may prioritise immune-related pathways over its metabolic functions. Intestinal infections caused by Ascaridia galli and Heterakis gallinarum impair feed intake, nutrient absorption, and weight gain. Histomonas meleagridis, vectored by H. gallinarum, can also damage liver tissues, potentially impairing liver functions. This study examined the hepatic gene expression in three strains of chickens: Ross-308 (R), Lohmann Brown Plus (LB), and Lohmann Dual (LD), 2 weeks after an experimental infection (n = 18) with both A. galli and H. gallinarum or kept as uninfected control (n = 12). Furthermore, H. gallinarum infection led to a co-infection with H. meleagridis. The mixed infections reduced feed intake and the average daily weight gain (P < 0.001). The infections also increased the plasma concentrations of alpha (1)-acid glycoprotein and the antibody titre against H. meleagridis (P = 0.049), with no strain differences (P > 0.05). For host molecular response, 1887 genes were differentially expressed in LD, while 275 and 25 genes were differentially expressed in R and LB, respectively. The up-regulated genes in R and LD were mostly related to inflammatory and adaptive immune responses, while down-regulated genes in LD were involved in metabolic pathways, including gluconeogenesis. Despite performance differences among the strains, worm burdens were similar, but hepatic molecular responses differed significantly. Moreover, there was an indication of a shift in hepatic functions towards immune-related pathways. We, therefore, conclude that the liver shifts its functions from metabolic to immune-related activities in chickens when challenged with mixed parasite species.

Metabolic perturbation and oxidative damage induced by tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and tris(2-ethylhexyl) phosphate (TEHP) on Escherichia coli through integrative analyses of metabolome.

Organophosphate esters (OPEs) are one of the emerging environmental threats, causing the hazard to ecosystem safety and human health. Yet, the toxic effects and metabolic response mechanism after Escherichia coli (E.coli) exposed to TDCIPP and TEHP is inconclusive. Herein, the levels of SOD and CAT were elevated in a concentration-dependent manner, accompanied with the increase of MDA contents, signifying the activation of antioxidant response and occurrence of lipid peroxidation. Oxidative damage mediated by excessive accumulation of ROS decreased membrane potential and inhibited membrane protein synthesis, causing membrane protein dysfunction. Integrative analyses of GC-MS and LC-MS based metabolomics evinced that significant perturbation to the carbohydrate metabolism, nucleotide metabolism, lipids metabolism, amino acid metabolism, organic acids metabolism were induced following exposure to TDCIPP and TEHP in E.coli, resulting in metabolic reprogramming. Additionally, metabolites including PE(16:1(5Z)/15:0), PA(17:0/15:1(9Z)), PC(20:2(11Z,14Z)/12:0), LysoPC(18:3(6Z,9Z,12Z)/0:0) were significantly upregulated, manifesting that cell membrane protective molecule was afforded by these differential metabolites to improve permeability and fluidity. Overall, current findings generate new insights into the molecular toxicity mechanism by which E.coli respond to TDCIPP and TEHP stress and supply valuable information for potential ecological risks of OPEs on aquatic ecosystems.

Adjustments of the Phytochemical Profile of Broccoli to Low and High Growing Temperatures: Implications for the Bioactivity of Its Extracts.

Climate change causes shifts in temperature patterns, and plants adapt their chemical content in order to survive. We compared the effect of low (LT) and high (HT) growing temperatures on the phytochemical content of broccoli (Brassica oleracea L. convar. botrytis (L.) Alef. var. cymosa Duch.) microgreens and the bioactivity of their extracts. Using different spectrophotometric, LC-MS/MS, GC-MS, and statistical methods, we found that LT increased the total phenolics and tannins in broccoli. The total glucosinolates were also increased by LT; however, they were decreased by HT. Soluble sugars, known osmoprotectants, were increased by both types of stress, considerably more by HT than LT, suggesting that HT causes a more intense osmotic imbalance. Both temperatures were detrimental for chlorophyll, with HT being more impactful than LT. HT increased hormone indole-3-acetic acid, implying an important role in broccoli's defense. Ferulic and sinapic acid showed a trade-off scheme: HT increased ferulic while LT increased sinapic acid. Both stresses decreased the potential of broccoli to act against H2O2 damage in mouse embryonal fibroblasts (MEF), human keratinocytes, and liver cancer cells. Among the tested cell types treated by H2O2, the most significant reduction in ROS (36.61%) was recorded in MEF cells treated with RT extracts. The potential of broccoli extracts to inhibit α-amylase increased following both temperature stresses; however, the inhibition of pancreatic lipase was increased by LT only. From the perspective of nutritional value, and based on the obtained results, we conclude that LT conditions result in more nutritious broccoli microgreens than HT.

Metabolism, antioxidant and immunity in acute and chronic hypoxic stress and the improving effect of vitamin C in the channel catfish (Ictalurus punctatus).

Hypoxia is the most significant factor that threatens the health and even survival of freshwater and marine fish. Priority should be given to the investigation of hypoxia adaptation mechanisms and their subsequent modulation. Acute and chronic studies were designed for the current study. Acute hypoxia comprised of normoxia dissolved oxygen (DO) 7.0 ± 0.5 mg/mL (N0), low-oxygen 5.0 ± 0.5 mg/mL(L0), and hypoxia 1.0 ± 0.1 mg/mL (H0) and 300 mg/L Vc for hypoxia regulation (N300, L300, H300). Chronic hypoxia comprised of normoxia (DO 7.0 ± 0.5 mg/mL) with 50 mg/kg Vc in the diet (N50) and low oxygen (5.0 ± 0.5 mg/mL) with 50, 250, 500 mg/kg Vc in the diet (L50, L250, L500) to assess the effect of Vc in hypoxia. The growth, behavior, hematological parameters, metabolism, antioxidants, and related inflammatory factors of channel catfish were investigated, and it was found that channel catfish have a variety of adaptive mechanisms in response to acute and chronic hypoxia. Under acute 5 mg/mL DO, the body color lightened (P < 0.05) and reverted to normal with 300 mg/mL Vc. PLT was significantly elevated after 300 mg/L Vc (P < 0.05), indicating that Vc can effectively restore hemostasis following oxygen-induced tissue damage. Under acute hypoxia, the significantly increased of cortisol, blood glucose, the gene of pyruvate kinase (pk), and phosphofructokinase (pfk), together with the decreased expression of fructose1,6-bisphosphatase (fbp) and the reduction in myoglycogen, suggested that Vc might enhance the glycolytic ability of the channel catfish. And the enzyme activities of superoxide dismutase (SOD) and catalase (CAT) and the gene expression of sod rose significantly, showing that Vc might improve the antioxidant capacity of the channel catfish. The significant up-regulation of tumor necrosis factor-alpha (tnf-α), interleukin-1ß (il-1ß), and cd68 under acute hypoxia implies that hypoxia may generate inflammation in channel catfish, whereas the addition of Vc and down-regulation of these genes suggests that Vc suppresses inflammation under acute hypoxia. We found that the final weight, WGR, FCR, and FI of channel catfish were significantly reduced under chronic hypoxia, and that feeding 250 mg/kg of Vc in the diet was effective in alleviating the growth retardation caused by hypoxia. The significant increase in cortisol, blood glucose, myoglycogen, and the expression of tnf-α, il-1ß, and cd68 (P < 0.05) and the significant decrease in lactate (P < 0.05) under chronic hypoxia indicated that the channel catfish had gradually adapted to the survival threat posed by hypoxia and no longer relied on carbohydrates as their primary source of energy. While the addition of Vc did not appear to increase the energy supply of the fish under hypoxia in terms of glucose metabolism, but the significantly decreased expression of tnf-α, il-1ß, and cd68 (P < 0.05) also were found, indicating that chronic hypoxia, similar acute hypoxia, may increase inflammation in the channel catfish. This study indicates that under acute stress, channel catfish withstand stress by raising energy supply through glycolysis, and acute hypoxic stress significantly promotes inflammation in channel catfish, but Vc assists the channel catfish resist stress by raising glycolysis, antioxidant capacity, and decreasing the production of inflammatory markers. Under chronic hypoxia, the channel catfish no longer utilize carbohydrates as their primary energy source, and Vc may still effectively reduce inflammation in the channel catfish under hypoxia.

Plasma protein N-glycome composition associates with postprandial lipaemic response.

BACKGROUND: A dysregulated postprandial metabolic response is a risk factor for chronic diseases, including type 2 diabetes mellitus (T2DM). The plasma protein N-glycome is implicated in both lipid metabolism and T2DM risk. Hence, we first investigate the relationship between the N-glycome and postprandial metabolism and then explore the mediatory role of the plasma N-glycome in the relationship between postprandial lipaemia and T2DM. METHODS: We included 995 individuals from the ZOE-PREDICT 1 study with plasma N-glycans measured by ultra-performance liquid chromatography at fasting and triglyceride, insulin, and glucose levels measured at fasting and following a mixed-meal challenge. Linear mixed models were used to investigate the associations between plasma protein N-glycosylation and metabolic response (fasting, postprandial (Cmax), or change from fasting). A mediation analysis was used to further explore the relationship of the N-glycome in the prediabetes (HbA1c = 39-47 mmol/mol (5.7-6.5%))-postprandial lipaemia association. RESULTS: We identified 36 out of 55 glycans significantly associated with postprandial triglycerides (Cmax ß ranging from -0.28 for low-branched glycans to 0.30 for GP26) after adjusting for covariates and multiple testing (padjusted < 0.05). N-glycome composition explained 12.6% of the variance in postprandial triglycerides not already explained by traditional risk factors. Twenty-seven glycans were also associated with postprandial glucose and 12 with postprandial insulin. Additionally, 3 of the postprandial triglyceride-associated glycans (GP9, GP11, and GP32) also correlate with prediabetes and partially mediate the relationship between prediabetes and postprandial triglycerides. CONCLUSIONS: This study provides a comprehensive overview of the interconnections between plasma protein N-glycosylation and postprandial responses, demonstrating the incremental predictive benefit of N-glycans. We also suggest a considerable proportion of the effect of prediabetes on postprandial triglycerides is mediated by some plasma N-glycans.

Multi-tissue transcriptomic and serum metabolomic assessment reveals systemic implications of acute ozone-induced stress response in male Wistar Kyoto rats.

Air pollutant exposures have been linked to systemic disease; however, the underlying mechanisms between responses of the target tissue and systemic effects are poorly understood. A prototypic inducer of stress, ozone causes respiratory and systemic multiorgan effects through activation of a neuroendocrine stress response. The goal of this study was to assess transcriptomic signatures of multiple tissues and serum metabolomics to understand how neuroendocrine and adrenal-derived stress hormones contribute to multiorgan health outcomes. Male Wistar Kyoto rats (12-13 weeks old) were exposed to filtered air or 0.8 ppm ozone for 4-hours, and blood/tissues were collected immediately post-exposure. Each tissue had distinct expression profiles at baseline. Ozone changed 1,640 genes in lung, 274 in hypothalamus, 2,516 in adrenals, 1,333 in liver, 1,242 in adipose, and 5,102 in muscle (adjusted p-value < 0.1, absolute fold-change > 50%). Serum metabolomic analysis identified 863 metabolites, of which 447 were significantly altered in ozone-exposed rats (adjusted p-value < 0.1, absolute fold change > 20%). A total of 6 genes were differentially expressed in all 6 tissues. Glucocorticoid signaling, hypoxia, and GPCR signaling were commonly changed, but ozone induced tissue-specific changes in oxidative stress, immune processes, and metabolic pathways. Genes upregulated by TNF-mediated NFkB signaling were differentially expressed in all ozone-exposed tissues, but those defining inflammatory response were tissue-specific. Upstream predictor analysis identified common mediators of effects including glucocorticoids, although the specific genes responsible for these predictors varied by tissue. Metabolomic analysis showed major changes in lipids, amino acids, and metabolites linked to the gut microbiome, concordant with transcriptional changes identified through pathway analysis within liver, muscle, and adipose tissues. The distribution of receptors and transcriptional mechanisms underlying the ozone-induced stress response are tissue-specific and involve induction of unique gene networks and metabolic phenotypes, but the shared initiating triggers converge into shared pathway-level responses. This multi-tissue transcriptomic analysis, combined with circulating metabolomic assessment, allows characterization of the systemic inhaled pollutant-induced stress response.

The prognostic value of [18F]FDG PET/CT based response monitoring in metastatic melanoma patients undergoing immunotherapy: comparison of different metabolic criteria.

PURPOSE: To investigate the prognostic value of [18F]FDG PET/CT as part of response monitoring in metastatic melanoma patients treated with immune checkpoint inhibitors (ICIs). METHODS: Sixty-seven patients underwent [18F]FDG PET/CT before start of treatment (baseline PET/CT), after two cycles (interim PET/CT) and after four cycles of ICIs administration (late PET/CT). Metabolic response evaluation was based on the conventional EORTC and PERCIST criteria, as well as the newly introduced, immunotherapy-modified PERCIMT, imPERCIST5 and iPERCIST criteria. Metabolic response to immunotherapy was classified according to four response groups (complete metabolic response [CMR], partial metabolic response [PMR], stable metabolic disease [SMD], progressive metabolic disease [PMD]), and further dichotomized by response rate (responders = [CMR] + [PMR] vs. non-responders = [PMD] + [SMD]), and disease control rate (disease control = [CMR] + [PMR] + [SMD] vs. [PMD]). The spleen-to-liver SUV ratios (SLRmean, SLRmax) and bone marrow-to-liver SUV ratios (BLRmean, BLRmax) were also calculated. The results of PET/CT were correlated with patients' overall survival (OS). RESULTS: Median patient follow up [95% CI] was 61.5 months [45.3 - 66.7 months]. On interim PET/CT, the application of the novel PERCIMT demonstrated significantly longer survival for metabolic responders, while the rest criteria revealed no significant survival differences between the different response groups. Respectively on late PET/CT, both a trend for longer OS and significantly longer OS were observed in patients responding to ICIs with metabolic response and disease control after application of various criteria, both conventional and immunotherapy-modified. Moreover, patients with lower SLRmean values demonstrated significantly longer OS. CONCLUSION: In patients with metastatic melanoma PET/CT-based response assessment after four ICIs cycles is significantly associated with OS after application of different metabolic criteria. The prognostic performance of the modality is also high after the first two ICIs cycles, especially with employment of novel criteria. In addition, investigation of spleen glucose metabolism may provide further prognostic information.

The glutamatergic drive to breathe is reduced in severe but not moderate hypoxia in Damaraland mole-rats.

Damaraland mole-rats (Fukomys damarensis) are a hypoxia-tolerant fossorial species that exhibit a robust hypoxic metabolic response (HMR) and blunted hypoxic ventilatory response (HVR). Whereas the HVR of most adult mammals is mediated by increased excitatory glutamatergic signalling, naked mole-rats, which are closely related to Damaraland mole-rats, do not utilize this pathway. Given their phylogenetic relationship and similar lifestyles, we hypothesized that the signalling mechanisms underlying physiological responses to acute hypoxia in Damaraland mole-rats are like those of naked mole-rats. To test this, we used pharmacological antagonists of glutamatergic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) and N-methyl-d-aspartate receptors (NMDARs), combined with plethysmography, respirometry and thermal RFID chips, to non-invasively evaluate the role of excitatory AMPAR and NMDAR signalling in mediating ventilatory, metabolic and thermoregulatory responses, respectively, to 1 h of 5 or 7% O2. We found that AMPAR or NMDAR antagonism have minimal impacts on the HMR or hypoxia-mediated changes in thermoregulation. Conversely, the 'blunted' HVR of Damaraland mole-rats is reduced by either AMPAR or NMDAR antagonism such that the onset of the HVR occurs in less severe hypoxia. In more severe hypoxia, antagonists have no impact, suggesting that these receptors are already inhibited. Together, these findings indicate that the glutamatergic drive to breathe decreases in Damaraland mole-rats exposed to severe hypoxia. These findings differ from other adult mammals, in which the glutamatergic drive to breathe increases with hypoxia.

Physiological responses to hypoxia are constrained by environmental temperature in heterothermic tenrecs.

Malagasy tenrecs are placental hibernating mammals that seal the entrances to their burrows and hibernate either singly or in groups for 8-9 months, which is likely to create a hypoxic and hypercapnic burrow environment. Therefore, we hypothesized that tenrecs are tolerant to environmental hypoxia and hypercapnia. Many hypoxia- and hypercapnia-tolerant fossorial mammals respond to hypoxia by decreasing metabolic rate and thermogenesis, and have blunted ventilatory responses to both environmental hypoxia and hypercapnia. However, tenrecs exhibit extreme metabolic and thermoregulatory plasticity, which exceeds that of most heterothermic mammals and approaches that of ectothermic reptiles. Thus, we predicted that tenrecs would have abnormal physiological responses to hypoxia and hypercapnia relative to other fossorial mammals. To test this, we exposed common tenrecs (Tenrec ecaudatus) to moderate and severe hypoxia (9 and 4% O2) or hypercapnia (5 and 10% CO2) in either 28 or 16°C while non-invasively measuring metabolic rate, thermogenesis and ventilation. We found that tenrecs exhibit robust metabolic decreases in both hypoxia and hypercapnia. Furthermore, tenrecs have blunted ventilatory responses to both hypoxia and hypercapnia, and these responses are highly temperature sensitive such that they are reduced or absent in 16°C. Thermoregulation was highly variable in 16°C but constrained in 28°C across all treatment conditions and was not impacted by hypoxia or hypercapnia, unlike in other heterothermic mammals. Taken together, our results indicate that physiological responses to hypoxia and hypercapnia in tenrecs are highly dependent on environmental temperature and differ from those of other mammalian heterotherms.

Metabolic tumor constitution is superior to tumor regression grading for evaluating response to neoadjuvant therapy of esophageal adenocarcinoma patients.

The response to neoadjuvant therapy can vary widely between individual patients. Histopathological tumor regression grading (TRG) is a strong factor for treatment response and survival prognosis of esophageal adenocarcinoma (EAC) patients following neoadjuvant treatment and surgery. However, TRG systems are usually based on the estimation of residual tumor but do not consider stromal or metabolic changes after treatment. Spatial metabolomics analysis is a powerful tool for molecular tissue phenotyping but has not been used so far in the context of neoadjuvant treatment of esophageal cancer. We used imaging mass spectrometry to assess the potential of spatial metabolomics on tumor and stroma tissue for evaluating therapy response of neoadjuvant-treated EAC patients. With an accuracy of 89.7%, the binary classifier trained on spatial tumor metabolite data proved to be superior for stratifying patients when compared with histopathological response assessment, which had an accuracy of 70.5%. Sensitivities and specificities for the poor and favorable survival patient groups ranged from 84.9% to 93.3% using the metabolic classifier and from 62.2% to 78.1% using TRG. The tumor classifier was the only significant prognostic factor (HR 3.38, 95% CI 1.40-8.12, p = 0.007) when adjusted for clinicopathological parameters such as TRG (HR 1.01, 95% CI 0.67-1.53, p = 0.968) or stromal classifier (HR 1.86, 95% CI 0.81-4.25, p = 0.143). The classifier even allowed us to further stratify patients within the TRG1-3 categories. The underlying mechanisms of response to treatment have been figured out through network analysis. In summary, metabolic response evaluation outperformed histopathological response evaluation in our study with regard to prognostic stratification. This finding indicates that the metabolic constitution of the tumor may have a greater impact on patient survival than the quantity of residual tumor cells or the stroma. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Influence of fasting during the night shift on next day eating behavior, hunger, and glucose and insulin levels: a randomized, three-condition, crossover trial.

AIMS: To investigate the influence of fasting during the night shift on eating behavior, hunger, glucose and insulin levels the following day. METHODS: Study with 10 male police officers who have been working at night. Participants were tested under three different conditions separated by at least 6 days of washout in a randomized, crossover design: "Night Shift Fasting" (NSF)-two nights of fasting during the night shift; "Night Shift Eating" (NSE)-two nights with the consumption of a standardized meal during the night shift (678 ± 42 kcal consumed at ~ 0200 h); and "Nighttime Sleep" (NS)-two nights of sleep. The morning after, blood glucose and insulin and hunger ratings were assessed, and food intake was assessed with an ad libitum test meal. Food intake was also assessed throughout the remainder of the day using a food record. Generalized Estimating Equations were used to analyze the effect of experimental condition. RESULTS: Food intake during the test meal, especially of proteins and fats, was higher after fasting during the night shift compared to the other conditions (p < 0.05), whereas desire to eat scores were lower after the NSF compared to NSE condition (p = 0.043). Hunger levels were lower after the NSF compared to the NS condition (p = 0.012). Insulin and HOMA-IR were also lower in the morning after NSF (p < 0.001). CONCLUSION: Fasting during the night shift leads to not only a higher intake of energy and macronutrients both in the early morning after work and throughout the next day, but also lower insulin levels and HOMA-IR in the morning. REGISTRATION NUMBER OF CLINICAL TRIAL: NCT03800732. Initial release: 01/09/2019. Last release: 02/23/2022.

A review of anammox metabolic response to environmental factors: Characteristics and mechanisms.

Anaerobic ammonium oxidation (anammox) is a promising low carbon and economic biological nitrogen removal technology. Considering the anammox technology has been easily restricted by environmental factors in practical engineering applications, therefore, it is necessary to understand the metabolic response characteristics of anammox bacteria to different environmental factors, and then guide the application of the anammox process. This review presented the latest advances of the research progress of the effects of different environmental factors on the metabolic pathway of anammox bacteria. The effects as well as mechanisms of conventional environmental factors and emerging pollutants on the anammox metabolic processes were summarized. Also, the role of quorum sensing (QS) mediating the bacteria growth, gene expression and other metabolic process in the anammox system were also reviewed. Finally, interaction and cross-feeding mechanisms of microbial communities in the anammox system were discussed. This review systematically summarized the variations of metabolic mechanism response to the external environment and cross-feeding interactions in the anammox process, which would provide an in-depth understanding for the anammox metabolic process and a comprehensive guidance for future anammox-related metabolic studies and engineering applications.

[18F]FDG-PET accurately identifies pathological response early upon neoadjuvant immune checkpoint blockade in head and neck squamous cell carcinoma.

PURPOSE: To investigate the utility of [18F]FDG-PET as an imaging biomarker for pathological response early upon neoadjuvant immune checkpoint blockade (ICB) in patients with head and neck squamous cell carcinoma (HNSCC) before surgery. METHODS: In the IMCISION trial (NCT03003637), 32 patients with stage II‒IVb HNSCC were treated with neoadjuvant nivolumab with (n = 26) or without (n = 6) ipilimumab (weeks 1 and 3) before surgery (week 5). [18F]FDG-PET/CT scans were acquired at baseline and shortly before surgery in 21 patients. Images were analysed for SUVmax, SUVmean, metabolic tumour volume (MTV), and total lesion glycolysis (TLG). Major and partial pathological responses (MPR and PPR, respectively) to immunotherapy were identified based on the residual viable tumour in the resected primary tumour specimen (≤ 10% and 11-50%, respectively). Pathological response in lymph node metastases was assessed separately. Response for the 2 [18F]FDG-PET-analysable patients who did not undergo surgery was determined clinically and per MR-RECIST v.1.1. A patient with a primary tumour MPR, PPR, or primary tumour MR-RECIST-based response upon immunotherapy was called a responder. RESULTS: Median ΔSUVmax, ΔSUVmean, ΔMTV, and ΔTLG decreased in the 8 responders and were significantly lower compared to the 13 non-responders (P = 0.05, P = 0.002, P < 0.001, and P < 0.001). A ΔMTV or ΔTLG of at least - 12.5% detected a primary tumour response with 95% accuracy, compared to 86% for the EORTC criteria. None of the patients with a ΔTLG of - 12.5% or more at the primary tumour site developed a relapse (median FU 23.0 months since surgery). Lymph node metastases with a PPR or MPR (5 metastases in 3 patients) showed a significant decrease in SUVmax (median - 3.1, P = 0.04). However, a SUVmax increase (median + 2.1) was observed in 27 lymph nodes (in 11 patients), while only 13 lymph nodes (48%) contained metastases in the corresponding neck dissection specimen. CONCLUSIONS: Primary tumour response assessment using [18F]FDG-PET-based ΔMTV and ΔTLG accurately identifies pathological responses early upon neoadjuvant ICB in HNSCC, outperforming the EORTC criteria, although pseudoprogression is seen in neck lymph nodes. [18F]FDG-PET could, upon validation, select HNSCC patients for response-driven treatment adaptation in future trials. TRIAL REGISTRATION: https://www. CLINICALTRIALS: gov/ , NCT03003637, December 28, 2016.

Adaptations to a hypoxic lifestyle in naked mole-rats.

Hypoxia is one of the strongest environmental drivers of cellular and physiological adaptation. Although most mammals are largely intolerant of hypoxia, some specialized species have evolved mitigative strategies to tolerate hypoxic niches. Among the most hypoxia-tolerant mammals are naked mole-rats (Heterocephalus glaber), a eusocial species of subterranean rodent native to eastern Africa. In hypoxia, naked mole-rats maintain consciousness and remain active despite a robust and rapid suppression of metabolic rate, which is mediated by numerous behavioural, physiological and cellular strategies. Conversely, hypoxia-intolerant mammals and most other hypoxia-tolerant mammals cannot achieve the same degree of metabolic savings while staying active in hypoxia and must also increase oxygen supply to tissues, and/or enter torpor. Intriguingly, recent studies suggest that naked mole-rats share many cellular strategies with non-mammalian vertebrate champions of anoxia tolerance, including the use of alternative metabolic end-products and potent pH buffering mechanisms to mitigate cellular acidification due to upregulation of anaerobic metabolic pathways, rapid mitochondrial remodelling to favour increased respiratory efficiency, and systemic shifts in energy prioritization to maintain brain function over that of other tissues. Herein, I discuss what is known regarding adaptations of naked mole-rats to a hypoxic lifestyle, and contrast strategies employed by this species to those of hypoxia-intolerant mammals, closely related African mole-rats, other well-studied hypoxia-tolerant mammals, and non-mammalian vertebrate champions of anoxia tolerance. I also discuss the neotenic theory of hypoxia tolerance - a leading theory that may explain the evolutionary origins of hypoxia tolerance in mammals - and highlight promising but underexplored avenues of hypoxia-related research in this fascinating model organism.

Biochemical, metabolic, and immune responses of mud crab (Scylla paramamosain) after mud crab reovirus infection.

Mud crab reovirus (MCRV) is a serious pathogen that leads to large economic losses in the mud crab farming. However, the molecular mechanism of the immune response after MCRV infection is unclear. In the present study, physiological, transcriptomic, and metabolomic responses after MCRV infection were investigated. The results showed that MCRV infection could increase lactate dehydrogenase, alanine aminotransferase, and aspartate aminotransferase activities. MCRV infection decreased antioxidant enzyme activity levels, induced oxidative stress, and caused severe histological damage. Transcriptome analysis identified 416 differentially expressed genes, including 354 up-regulated and 62 down-regulated genes. The detoxification, immune response, and metabolic processes-related genes were found. The results showed that two key pathways including phagocytosis and apoptosis played important roles in response to MCRV infection. The combination of transcriptomic and metabolomic analyses showed that related metabolic pathways, such as glycolysis, citrate cycle, lipid, and amino acid metabolism were also significantly disrupted. Moreover, the biosynthesis of unsaturated fatty acids was activated in response to MCRV infection. This study provided a novel insight into the understanding of cellular mechanisms in crustaceans against viral invasion.

Response mechanism of microbial community during anaerobic biotransformation of marine toxin domoic acid.

Domoic acid (DA) is a potent neurotoxin produced by toxigenic Pseudo-nitzschia blooms and quickly transfers to the benthic anaerobic environment by marine snow particles. DA anaerobic biotransformation is driven by microbial interactions, in which trace amounts of DA can cause physiological stress in marine microorganisms. However, the underlying response mechanisms of microbial community to DA stress remain unclear. In this study, we utilized an anaerobic marine DA-degrading consortium GLY (using glycine as co-substrate) to systematically investigate the global response mechanisms of microbial community during DA anaerobic biotransformation.16S rRNA gene sequencing and metatranscriptomic analyses were applied to measure microbial community structure, function and metabolic responses. Results showed that DA stress markedly changed the composition of main species, with increased levels of Firmicutes and decreased levels of Proteobacteria, Cyanobacteria, Bacteroidetes and Actinobacteria. Several genera of tolerated bacteria (Bacillus and Solibacillus) were increased, while, Stenotrophomonas, Sphingomonas and Acinetobacter were decreased. Metatranscriptomic analyses indicated that DA stimulated the expression of quorum sensing, extracellular polymeric substance (EPS) production, sporulation, membrane transporters, bacterial chemotaxis, flagellar assembly and ribosome protection in community, promoting bacterial adaptation ability under DA stress. Moreover, amino acid metabolism, carbohydrate metabolism and lipid metabolism were modulated during DA anaerobic biotransformation to reduce metabolic burden, increase metabolic demands for EPS production and DA degradation. This study provides the new insights into response of microbial community to DA stress and its potential impact on benthic microorganisms in marine environments.

Metabolic response provides insights into the mechanism of adaption to hypoxia in largemouth bass (Micropterus salmoides) under intermittent hypoxic conditions.

In metabolism, molecular oxygen is a necessary substrate. Oxygen imbalances are linked to a variety of circumstances in the organism's homeostasis. Recently, the positive effects of hypoxia treatment in improving exercise ability and hypoxia tolerance have become a research focus. We explored the effects of intermittent hypoxia exposure (IHE, for one hour or three hours per day) on the hypoxia tolerance of largemouth bass in this study. The results showed that (1) IHE significantly reduced the LOEcrit (the critical O2 tension for loss of equilibrium) value of largemouth bass, indicating that its hypoxia tolerance was enhanced. (2) The level of oxidative stress in the liver decreased in the HH3 group (exposed to a hypoxic condition for 3 h per day) compared to HH1 group (exposed to a hypoxic condition for 1 h per day). (3) IHE reduced the content of lactic acid and enhanced the process of gluconeogenesis in the liver. (4) Importantly, lipid mobilization and fatty acid oxidation in the liver of largemouth bass were significantly enhanced during IHE. In short, the results of this study indicate that IHE can improve hypoxia tolerance by regulating the energy metabolism of largemouth bass.

Porphyromonas gingivalis W83 Membrane Components Induce Distinct Profiles of Metabolic Genes in Oral Squamous Carcinoma Cells.

Periodontitis, a chronic inflammatory disease is caused by a bacterial biofilm, affecting all periodontal tissues and structures. This chronic disease seems to be associated with cancer since, in general, inflammation intensifies the risk for carcinoma development and progression. Interactions between periodontal pathogens and the host immune response induce the onset of periodontitis and are responsible for its progression, among them Porphyromonas gingivalis (P. gingivalis), a Gram-negative anaerobic rod, capable of expressing a variety of virulence factors that is considered a keystone pathogen in periodontal biofilms. The aim of this study was to investigate the genome-wide impact of P. gingivalis W83 membranes on RNA expression of oral squamous carcinoma cells by transcriptome analysis. Human squamous cell carcinoma cells (SCC-25) were infected for 4 and 24 h with extracts from P. gingivalis W83 membrane, harvested, and RNA was extracted. RNA sequencing was performed, and differential gene expression and enrichment were analyzed using GO, KEGG, and REACTOME. The results of transcriptome analysis were validated using quantitative real-time PCR with selected genes. Differential gene expression analysis resulted in the upregulation of 15 genes and downregulation of 1 gene after 4 h. After 24 h, 61 genes were upregulated and 278 downregulated. GO, KEGG, and REACTONE enrichment analysis revealed a strong metabolic transcriptomic response signature, demonstrating altered gene expressions after 4 h and 24 h that mainly belong to cell metabolic pathways and replication. Real-time PCR of selected genes belonging to immune response, signaling, and metabolism revealed upregulated expression of CCL20, CXCL8, NFkBIA, TNFAIP3, TRAF5, CYP1A1, and NOD2. This work sheds light on the RNA transcriptome of human oral squamous carcinoma cells following stimulation with P. gingivalis membranes and identifies a strong metabolic gene expression response to this periodontal pathogen. The data provide a base for future studies of molecular and cellular interactions between P. gingivalis and oral epithelium to elucidate the basic mechanisms of periodontitis and the development of cancer.

Iron deficiency leads to repression of a non-canonical methionine salvage pathway in Schizosaccharomyces pombe.

The methionine salvage pathway (MSP) regenerates methionine from 5'-methylthioadenosine (MTA). Aerobic MSP consists of six enzymatic steps. The mug14+ and adi1+ genes that are involved in the third and fifth steps of the pathway are repressed when Schizosaccharomyces pombe undergoes a transition from high- to low-iron conditions. Results consistently show that methionine auxotrophic cells (met6Δ) require iron for growth in the presence of MTA as the sole source of methionine. Inactivation of the iron-using protein Adi1 leads to defects in the utilization of MTA. In the case of the third step of the pathway, co-expression of two distinct proteins, Mta3 and Mde1, is required. These proteins are interdependent to rescue MTA-dependent growth deficit of met6Δ cells. Coimmunoprecipitation experiments showed that Mta3 is a binding partner of Mde1. Meiotic met6Δ cells co-expressing mta3+ and mde1+ or mta3+ and mug14+ produce comparable levels of spores in the presence of MTA, revealing that Mde1 and Mug14 share a common function when co-expressed with Mta3 in sporulating cells. In sum, our findings unveil several novel features of MSP, especially with respect to its regulation by iron and the discovery of a non-canonical third enzymatic step in the fission yeast.

Two Newly Introduced Wolbachia Endosymbionts Induce Cell Host Differences in Competitiveness and Metabolic Responses.

Wolbachia endosymbionts can induce multiple reproductive manipulations in their hosts, with cytoplasmic incompatibility (CI) being one of the most common manipulations. Two important agricultural pests, the white-backed planthopper (Sogatella furcifera) and the brown planthopper (Nilaparvata lugens), are usually infected with CI-inducing Wolbachia strain wFur and non-CI-inducing Wolbachia strain wLug, respectively. The biological effects of these infections when present in a host cell are unknown. Here, we introduced the two Wolbachia strains into an Aedes albopictus cell line to stably establish a wFur-infected cell line (WFI) and a wLug-infected cell line (WLI). In a mixed culture, WFI cells were completely replaced by WLI cells, pointing to a stronger competitiveness of the WLI cell line. We found that infection by both Wolbachia strains reduced cell growth rates, but WLI had a higher cell growth rate than WFI, and this difference in cell growth rate combined with possible Wolbachia differences in diffusivity may have affected cell competitiveness. By examining gene expression and metabolites in the two lines, we found that some genes and key metabolites responded to differences in cell competitiveness. These results point to potential mechanisms that could contribute to the relative performance of hosts infected by these strains and also highlight the substantial impact of a non-CI Wolbachia on metabolism, which may in turn influence the fitness of its native host. IMPORTANCEWolbachia transinfection in insects can be used to suppress pests and block virus transmission. We stably introduced two Wolbachia strains from rice planthoppers into cell lines of an important arbovirus mosquito vector, Aedes albopictus. The levels of competitiveness of host cells from the lines infected by the two Wolbachia strains were different, as were metabolic responses of the cell lines. These results suggest potential metabolic effects of Wolbachia on native hosts that could be exploited when they are transinfected into novel hosts for pest control.