Changes In Catabolism Research Articles

Immunomodulatory Effect of Vitamin D3 in Rats with Induced Osteoarthritis

Background: The (OA) caused by imbalance between anabolic and catabolic processes within the cartilage ,one of the effects of increased catabolic changes is presence of products of extracellular matrix degradation in the synovial fluid which lead to the joint microenvironment alteration which attempt. Aim of study: Evaluate the influence of induce osteoarthritis (OA) on knee joint and looking on (OA) effect as local immune response in addition to the possible role of vitamin (D3) as protective and repairing agent against (OA) complications. Methods: Total number of rats male (89) were used and divided into three groups, first group (control group) (19) rats, second group (OA induced) (35) rats injected with papain enzyme at dose of (10 mg), treated group (35) rats which firstly injected with papain enzyme at dose (10 mg) then after (2) weeks of injection, treated the rats with vitamin D. Results and Dicussion: Macroscopic observations revealed to cartilage surface erosion , fibrillation , hypertrophied condyles, degeneration. The rats knee joints that treated (2) weeks with vitamin (D3) post (OA) induced showed smooth, intact cartilage surface. Radiographic images indicated to narrowing joints cavity (space) at knee joint of (OA) rat model, destruction of epiphyseal plate, while the results related to (OA) rats treated with vitamin (D3) showed no osteophyte growth , the synovial cavity nearest to the normal, no defect. Conclusion: Vitamin (D) prevent the stability and life of chondrocytes which lead to cartilage protection and synthesis of (ECM) , and inhibite the inflammation resulted from cartilage damaged.

Temporomandibular joint disc responses to installation and removal of the experimental malocclusion.

Aberrant occlusion and aging are two main risks for temporomandibular joint (TMJ) degeneration. To assess the combined impact of occlusion and age on TMJ disc. To avoid the confounding impact of gender, presently, 126 female C57BL/6J mice, 63 youngsters, 6-week old and 63 adults, 28-week old, were used. An experimental bilateral anterior crossbite (BAC) relation was created by installing metal tubes onto the mandibular incisors. Mice were sacrificed at 3, 7 and 11 weeks (n = 9). Additionally, the installed tubes were removed at 7 weeks in removal groups and the TMJs were sampled after another 4 weeks (n = 9). Disc changes were detected by histomorphology, immunohistochemistry, and western blot assays. Disc deformation was obvious in BAC groups. The typical change was hyperplasia at the posterior region of the disc where there was significant infiltration of inflammatory cells. Expressions of the inflammatory markers, including tumour necrosis factor-α and interleukin-1β, and the catabolic markers, including fibronectin (FN), FN N-terminal fragments, and vascular endothelial growth factor-A, were all increased. The changes were more obvious in adults than in youngsters. Removal of BAC attenuated inflammatory and catabolic changes in the youngsters, but the inflammatory markers recovered little in the adults. TMJ disc responds to BAC by degeneration and inflammation, and respond to BAC removal by rehabilitation. Adult discs show severer degeneration responses to BAC and a lower level of anti-inflammatory capability to BAC removal than the youngster's discs. Animals cannot be equated with humans. The human disc response to occlusion changes worth further exploration.

Exploring the impacts of ketogenic diet on reversible hepatic steatosis: initial analysis in male mice.

Metabolic dysfunction-associated fatty liver disease (MAFLD) is the most common chronic liver disease. Ketogenic diet (KD), a diet with very low intake in carbohydrates, gained popularity as a weight-loss approach. However, in mice models, it has been reported that an excess exposition of dietary fat induces hepatic insulin resistance and steatosis. However, data published is inconsistent. Herein, we investigated in a mouse model, the metabolic effects of KD and its contribution to the pathogenesis of NALFD. Mice were exposed to KD or CHOW diet for 12 weeks while a third group was exposed to KD for also 12 weeks and then switched to CHOW diet for 4 weeks to determine if we can rescue the phenotype. We evaluated the effects of diet treatments on fat distribution, glucose, and insulin homeostasis as well as hepatic steatosis. Mice fed with KD developed glucose intolerance but not insulin resistance accompanied by an increase of inflammation. KD-fed mice showed an increase of fat accumulation in white adipose tissue and liver. This effect could be explained by an increase in fat uptake by the liver with no changes of catabolism leading to MAFLD. Interestingly, we were able to rescue the phenotype by switching KD-fed mice for 4 weeks on a CHOW diet. Our studies demonstrate that even if mice develop hepatic steatosis and glucose intolerance after 12 weeks of KD, they do not develop insulin resistance and more importantly, the phenotype can be reversed by switching the mice from a KD to a CHOW.

Effects of dexamethasone and IGF-1 on post-traumatic osteoarthritis-like catabolic changes in a human cartilage-bone-synovium microphysiological system in space and ground control tissues on earth

Post-traumatic Osteoarthritis (PTOA) results from traumatic joint injuries (such as an ACL rupture). Mechanical impact and an immediate synovial inflammatory response can result in joint tissue degradation and longer-term progression to PTOA. Astronauts are susceptible to increased exercise-related joint injuries leading to altered musculoskeletal physiology, further escalated due to microgravity and increased exposure to ionizing radiation. We applied a human Cartilage-Bone-Synovium (CBS) coculture model to test the potential of low-dose dexamethasone (Dex) and IGF-1 in ameliorating PTOA-like degeneration on Earth and the International Space Station-National Laboratory (ISS-NL, ISS for short). CBS cocultures were established using osteochondral plugs (CB) subjected to compressive impact injury (INJ) followed by coculture with synovium (S) explants. Study groups consisted of control (CB); disease [CBS + INJ]; treatment [CBS + INJ + Dex + IGF-1]; and drug-safety [CB + Dex + IGF-1]. Outcome measures included cell viability, altered matrix glycosaminoglycans (GAG) and collagens, multiplex-ELISA quantification of released cytokines, histopathology, and metabolomic and proteomic analyses of spent media. A 21-day study on ISS-NL explored PTOA-like pathogenesis and treatment in microgravity. Tissue cards for study groups were cultured in custom-built culture chambers within multi-use variable-g platforms (MVPs). A marked upregulation in the release of inflammatory cytokines and tissue-GAG loss was observed in CBS + INJ groups in space and ground controls utilizing tissues from the same donors, similar to that reported in a previous multi-donor study on Earth; these changes were partly ameliorated by Dex + IGF-1, but with donor variability. Metabolomic and proteomic analyses revealed an array of distinct differences between metabolites/proteins released to the medium in Space versus on Earth.

Leveraging metabolic modeling and machine learning to uncover modulators of quiescence depth.

Quiescence, a temporary withdrawal from the cell cycle, plays a key role in tissue homeostasis and regeneration. Quiescence is increasingly viewed as a continuum between shallow and deep quiescence, reflecting different potentials to proliferate. The depth of quiescence is altered in a range of diseases and during aging. Here, we leveraged genome-scale metabolic modeling (GEM) to define the metabolic and epigenetic changes that take place with quiescence deepening. We discovered contrasting changes in lipid catabolism and anabolism and diverging trends in histone methylation and acetylation. We then built a multi-cell type machine learning model that accurately predicts quiescence depth in diverse biological contexts. Using both machine learning and genome-scale flux simulations, we performed high-throughput screening of chemical and genetic modulators of quiescence and identified novel small molecule and genetic modulators with relevance to cancer and aging.

Abstract 17256: Perturbations of Tryptophan Catabolism Through the Kynurenine Pathway Are Associated With Prolonged Mechanical Ventilation and Length of Stay After Stage 2 Palliation for Single Ventricle Heart Disease

Background: Infants with single ventricle heart disease (SVHD) have perturbed kynurenine pathway (KP) function prior to stage 2 palliation. Buildup of kynurenic acid—a byproduct of this pathway—is linked to worse outcomes post stage 2. To date, perturbations along the entire KP have not been delineated in SVHD infants at the time of stage 2 operation. Methods: This is a single center prospective cohort study of 75 infants with SVHD undergoing stage 2 palliation and 50 controls. Targeted analysis of KP metabolites was performed on serum samples via tandem mass spectroscopy prior to stage 2 (baseline) and post-operatively at 2, 24, and 48 hours. Results: Of the 9 KP metabolites, 7 were different between controls and SVHD at baseline (Figure 1A). SVHD infants had lower tryptophan and serotonin; and higher kynurenic acid, 3-hydroxykynurenine, anthranilic acid, picolinic acid, and 3-hydroxyanthranilic acid. After stage 2, there were time related changes in all KP metabolites except tryptophan (Figure 1B). Metabolite concentrations at baseline and 2 hours post-op were poorly correlated with outcomes. At 24 hours, decreases in tryptophan and serotonin along with elevations in kynurenine, kynurenic acid, 3-hydroxykynurine, and quinolinic acid concentrations correlated with outcomes (Figure 1C). At 48 hours, kynurenic acid remained positively correlated with all 3 outcomes (length of stay, hypoxia burden, and intubation length). Conclusions: We demonstrated numerous perturbations in the KP pathway at baseline in SVHD infants compared to controls. We also profiled the trajectory of each metabolite over the 48 hours post stage 2. The link between KP intermediates and poor outcomes post-operatively—but not at baseline—demonstrates that the acute, peri-operative changes in tryptophan catabolism in response to cardiopulmonary bypass are more important to tolerating new stage 2 physiology than chronic changes during the interstage period.

Flight muscle size reductions and functional changes following long-distance flight under variable humidity conditions in a migratory warbler.

Bird flight muscle can lose as much as 20% of its mass during a migratory flight due to protein catabolism, and catabolism can be further exacerbated under dehydrating conditions. However, the functional consequences of exercise and environment induced protein catabolism on muscle has not been examined. We hypothesized that prolonged flight would cause a decline in muscle mass, aerobic capacity, and contractile performance. This decline would be heightened for birds placed under dehydrating environmental conditions, which typically increases lean mass losses. Yellow-rumped warblers (Setophaga coronata) were exposed to dry or humid (12 or 80% relative humidity at 18°C) conditions for up to 6 h while at rest or undergoing flight. The pectoralis muscle was sampled after flight/rest or after 24 h of recovery, and contractile properties and enzymatic capacity for aerobic metabolism was measured. There was no change in lipid catabolism or force generation of the muscle due to flight or humidity, despite reductions in pectoralis dry mass immediately post-flight. However, there was a slowing of myosin-actin crossbridge kinetics under dry compared to humid conditions. Aerobic and contractile function is largely preserved after 6 h of exercise, suggesting that migratory birds preserve energy pathways and function in the muscle.

Metabolic Alterations in Canine Mammary Tumors.

Canine mammary tumors (CMTs) are among the most common diseases in female dogs and share similarities with human breast cancer, which makes these animals a model for comparative oncology studies. In these tumors, metabolic reprogramming is known as a hallmark of carcinogenesis whereby cells undergo adjustments to meet the high bioenergetic and biosynthetic demands of rapidly proliferating cells. However, such alterations are also vulnerabilities that may serve as a therapeutic strategy, which has mostly been tested in human clinical trials but is poorly explored in CMTs. In this dedicated review, we compiled the metabolic changes described for CMTs, emphasizing the metabolism of carbohydrates, amino acids, lipids, and mitochondrial functions. We observed key factors associated with the presence and aggressiveness of CMTs, such as an increase in glucose uptake followed by enhanced anaerobic glycolysis via the upregulation of glycolytic enzymes, changes in glutamine catabolism due to the overexpression of glutaminases, increased fatty acid oxidation, and distinct effects depending on lipid saturation, in addition to mitochondrial DNA, which is a hotspot for mutations. Therefore, more attention should be paid to this topic given that targeting metabolic fragilities could improve the outcome of CMTs.

#2616 DIAGNOSTIC VALUE OF THE HANDGRIP STRENGTH IN DETECTING PROTEIN-ENERGY WASTING AMONG HEMODIALYSIS PATIENTS AT NATIONAL KIDNEY AND TRANSPLANT INSTITUTE

Abstract Background and Aims Protein energy wasting (PEW) is a syndrome of adverse nutritional and catabolic changes common among chronic kidney disease (CKD) patients. Handgrip strength (HGS) was one of the methods of screening PEW mentioned in Kidney Disease Outcomes Quality Initiative guidelines. However, only few studies determined the validity of HGS in detecting PEW among maintenance hemodialysis (MHD) patients. The study aimed to determine the diagnostic validity of HGS in detecting PEW among MHD patients in a tertiary government hospital, with the following specific objectives: to determine the prevalence of PEW among MHD patients, to compare the demographic and clinical profile by PEW status, to identify the optimal cut-off point of HGS pre- and post-HD sessions in detecting PEW by sex, and to determine the following diagnostic value parameters of HGS pre- and post-HD sessions in detecting PEW by sex in terms of discriminative ability, accuracy, sensitivity, specificity, positive predictive value and negative predictive value. Method Participants included in this cross-sectional study are randomly selected patients undergoing MHD in National Kidney and Transplant Institute (NKTI) from September to October, 2022. Diagnosis of PEW was based on the Malnutrition Inflammation Score (MIS) ≥5. HGS was measured using a dynamometer pre- and post-dialysis sessions. Results A total of 143 patients were included in the study, and 53% were diagnosed with PEW. Pre-HD and post-HD HGS have acceptable discriminative ability based on Area Under the Curve >0.70 in detecting PEW regardless of patient sex. In males, a post-hemodialysis cut-off of <17.9 showed 72% sensitivity and 71% specificity in detecting PEW. Meanwhile, a pre-hemodialysis cut-off of <18.6 in females showed 83% sensitivity and 65% specificity in detecting PEW. Conclusion PEW is common among MHD patients in NKTI. The diagnostic performance of HGS in detecting PEW was found to be acceptable in both males and females. While both pre- and post-HD measures can be used in males, only the pre-HD measures are recommended for females. HGS can, therefore, be used as a non-expensive, accurate and objective screening assessment tool in detecting PEW for MHD patients. External validation of the proposed HGS cut-off values is still recommended.

HTRA1 from OVX rat osteoclasts causes detrimental effects on endplate chondrocytes through NF-κB

Endplate osteochondritis is considered one of the major causes of intervertebral disc degeneration (IVDD) and low back pain. Menopausal women have a higher rate of endplate cartilage degeneration than similarly aged men, but the related mechanisms are still unclear. Subchondral bone changes, mainly mediated by osteoblasts and osteoclasts, are considered an important reason for the degeneration of cartilage. This work explored the role of osteoclasts in endplate cartilage degeneration, as well as its underlying mechanisms. A rat ovariectomy (OVX) model was used to induce estrogen deficiency. Our experiments indicated that OVX significantly promoted osteoclastogenesis and anabolism and catabolism changes in endplate chondrocytes. OVX osteoclasts cause an imbalance between anabolism and catabolism in endplate chondrocytes, as shown by a decrease in anabolic markers such as Aggrecan and Collagen II, and an increase in catabolic markers such as a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) and matrix metalloproteinases (MMP13). Osteoclasts were also confirmed in this study to be able to secrete HtrA serine peptidase 1 (HTRA1), which resulted in increased catabolism in endplate chondrocytes through the NF-κB pathway under estrogen deficiency. This study demonstrated the involvement and mechanism of osteoclasts in the anabolism and catabolism changes of endplate cartilage under estrogen deficiency, and proposed a new strategy for the treatment of endplate osteochondritis and IVDD by targeting HTRA1.

Insights into the fatty acid binding protein of Pacific white shrimp (Litopenaeus vannamei) suffering acute hepatopancreatic necrosis disease infection

Acute hepatopancreatic necrosis disease (AHPND) has a significant economic impact on aquaculture worldwide. However, the molecular mechanism responsible for AHPND remains unknown. Our previous study demonstrated that the Litopenaeus vannamei fatty acid binding protein (LvFABP) interacted with the Vibrio parahaemolyticus toxin PirB, and that silencing LvFABP using RNA interference improved AHPND resistance in shrimp. Polyclonal antibodies against recombinant LvFABP and PirBvp toxin were produced to further elucidate the role of LvFABP in AHPND resistance. Immunofluorescence localization showed that LvFABP was abundant throughout the cytoplasm of the hepatopancreas cells, and a co-localization assay revealed that PirBvp directly interacted with LvFABP. Antibodies against LvFABP were able to partially block the binding of LvFABP to PirBvpin vitro and inhibited AHPND infection in vivo. Exogenous recombinant LvFABP had a partially neutralizing effect against AHPND and gave L. vannamei significant protection against infection. In addition, recombinant LvFABP treatment of L. vannamei significantly reduced the morphological damage to the shrimp following pathogen challenge. The transcriptomes of the L. vannamei hepatopancreas with and without V. parahaemolyticus infection after silencing of LvFABP by RNA interference were also explored. The results showed that AHPND infection could affect the health of L. vannamei via functional changes in carbohydrate metabolism, lipid metabolism, and transport and catabolism. Furthermore, silencing LvFABP could effectively protect metabolism, transport and catabolic homeostasis, thus enabling adaptation to further or prolonged AHPND infections. These findings provided a unique and important dataset that deepened our understanding of the pathological mechanism of AHPND and may help in the development of strategies to prevent and ameliorate the effects of bacterial diseases.

Adverse cardiac remodeling augments adipose tissue ß-adrenergic signaling and lipolysis counteracting diet-induced obesity

Cardiac triacylglycerol accumulation is a common characteristic of obesity and type 2 diabetes and strongly correlates with heart morbidity and mortality. We have previously shown that cardiomyocyte-specific perilipin 5 overexpression (Plin5-Tg) provokes significant cardiac steatosis via lowering cardiac lipolysis and fatty acid (FA) oxidation. In strong contrast to cardiac steatosis and lethal heart dysfunction in adipose triglyceride lipase deficiency, Plin5-Tg mice do not develop heart dysfunction and show a normal life span on chow diet. This finding prompted us to study heart function and energy metabolism in Plin5-Tg mice fed high-fat diet (HFD). Plin5-Tg mice showed adverse cardiac remodeling on HFD with heart function only being compromised in one-year-old mice, likely due to reduced cardiac FA uptake, thereby delaying deleterious cardiac lipotoxicity. Notably, Plin5-Tg mice were less obese and protected from glucose intolerance on HFD. Changes in cardiac energy catabolism in Plin5-Tg mice increased ß-adrenergic signaling, lipolytic, and thermogenic protein expression in adipose tissue ultimately counteracting HFD-induced obesity. Acute cold exposure further augmented ß-adrenergic signaling in Plin5-Tg mice, whereas housing at thermoneutrality did not protect Plin5-Tg mice from HFD-induced obesity albeit blood glucose and insulin levels remained low in transgenic mice. Overall, our data suggest that the limited capacity for myocardial FA oxidation on HFD increases cardiac stress in Plin5-Tg mice, thereby stimulating adipose tissue ß-adrenergic signaling, triacylglycerol catabolism, and thermogenesis. However, long-term HFD-mediated metabolic stress causes contractile dysfunction in Plin5-Tg mice, which emphasizes the importance of a carefully controlled dietary regime in patients with cardiac steatosis and hypertrophy.

FasL is a catabolic factor in alveolar bone homeostasis.

Fas ligand (FasL) belongs to the tumour necrosis factor superfamily regulating bone turnover, inflammation, and apoptosis. The appendicular and axial skeleton phenotype of mature Faslgld mice has been reported. The impact of FasL on the alveolar bone providing support for the teeth at mature stages under healthy and induced inflammatory conditions remains unknown. We performed a phenotypical analysis of mice carrying the homozygous Faslgld mutation and wild-type (WT) mice (C57BL/6) under healthy conditions and upon ligature-induced periodontitis. After 12 days, micro-computed tomography analysis revealed the distance between the cement enamel junction and the alveolar bone crest. Additional structural parameters, such as the bone volume fraction (BV/TV) and the periodontal ligament space volume, were measured. Histological analyses were performed to visualize the catabolic changes at the defect site. Healthy Faslgld mice were found to have more periodontal bone than their WT littermates. Faslgld had no significant effect on inflammatory osteolysis compared to WT controls with ligatures. Histology revealed eroded surfaces at the root and in the inter-proximal bone in both strains. Our findings suggest that FasL is a catabolic factor in alveolar bone homeostasis but it does not affect the inflammatory osteolysis.

Nutrition of elderly persons during a new coronavirus infection

A new coronavirus infection (COVID-19) of a particularly severe course is more often observed in the elderly, this is largely due to age-related immunological and metabolic changes, as well as polymorbidity. In the literature, increasing evidence highlights how malnutrition negatively affects the immune system functionality, impairing protection from infections.Individual vitamins and trace elements play an important role in supporting both innate and acquired immune defenses. Many chronic diseases such as diabetes and cardiovascular diseases in the elderly are often associated with a high risk of malnutrition and a poorer prognosis. The main causes of malnutrition are limited mobility, catabolic changes in skeletal muscles, as well as a decrease in food intake, which can be further aggravated in the elderly. In this article the role of nutrition of elderly patients in the period of a new coronavirus infection pandemic is analyzed. Nutrition is a determinant of the health status of older persons. Inadequate nutrition contributes to the progression of many diseases, and also increases the risk of adverse outcomes, including coronavirus infection. Therefore, it is important to assess the nutritional status of patients infected with COVID‐19 at all stages of treatment. It is imperative to provide adequate nutrition, which will make up for the deficiency of micro- / macronutrients, primarily protein and energy necessary for the recovery of the body.According to modern recommendations, the management program for elderly patients with COVID-19 should include measures aimed at screening, preventing and treatment of malnutrition.

The “post-weanling’s conundrum”: exploring the impact of infant and child feeding practices on early mortality in the Bronze Age burial cave of Moro de Alins, north-eastern Iberia, through stable isotope analysis

The relationship between infant and child feeding practices and early mortality is difficult to address in past societies. Here, stable carbon (δ13C) and nitrogen (δ15N) isotope measurements of bulk bone and sequential dentine samples of deciduous second and/or permanent first molars of four younger children, one older child, one late adolescent, and two young adults (n = 8) from Moro de Alins cave, north-eastern Iberia, are used to explore the potential impact of early-life nutrition on mortality in the Bronze Age. Isotope results are compatible with generally short exclusive breastfeeding and standard weaning periods compared to other pre-modern populations. However, there are differences in exclusive breastfeeding mean δ13C values and in Δ13C trophic shifts between exclusive breastfeeding and immediate post-weaning isotope values for those individuals who survived into adolescence and adulthood and those who did not. While the former seem to be consistent with trophic distances published for modern mother–infant pairs, the latter are above most of them. This may suggest that individuals who consumed similar foods to their mothers or suffered from less physiological stress during or after weaning had greater chances of survival during early childhood and beyond. Post-weaning seems to have been a particularly stressful period of life, where a number of instances of patterns of opposing isotopic covariance compatible with catabolic changes, often preceding death among non-survivors, are detected. This outcome shows the key role of nutritional and/or physiological status in early-life morbidity and mortality among partially and especially fully weaned children from pre-antibiotic, pre-vaccination, and poor sanitation contexts and proposes that adult survival is rooted in early life experiences, in keeping with the developmental origins of health and disease.

Impact of Fluid Flow Shear Stress on Osteoblast Differentiation and Cross-Talk with Articular Chondrocytes.

Bone cells, in particular osteoblasts, are capable of communication with each other during bone growth and homeostasis. More recently it has become clear that they also communicate with other cell-types; including chondrocytes in articular cartilage. One way that this process is facilitated is by interstitial fluid movement within the pericellular and extracellular matrices. This stimulus is also an important mechanical signal in skeletal tissues, and is known to generate shear stresses at the micron-scale (known as fluid flow shear stresses (FFSS)). The primary aim of this study was to develop and characterize an in vitro bone–cartilage crosstalk system, to examine the effect of FFSS on these cell types. Specifically, we evaluated the response of osteoblasts and chondrocytes to FFSS and the effect of FFSS-induced soluble factors from the former, on the latter. This system will ultimately be used to help us understand the role of subchondral bone damage in articular cartilage degeneration. We also carried out a comparison of responses between cell lines and primary murine cells in this work. Our findings demonstrate that primary cells produce a more reliable and reproducible response to FFSS. Furthermore we found that at lower magnitudes , direct FFSS produces anabolic responses in both chondrocytes and osteoblasts, whereas higher levels produce more catabolic responses. Finally we show that exposure to osteoblast-derived factors in conditioned media experiments produced similarly catabolic changes in primary chondrocytes.

How to follow lipid droplets dynamics during adipocyte metabolism.

Lipid droplets (LDs) are important cellular organelles due to their ability to accumulate and store lipids. LD dynamics are associated with various cellular and metabolic processes. Accurate monitoring of LD's size and shape is of prime importance as it indicates the metabolic status of the cells. Unintrusive continuous quantification techniques have a clear advantage in analyzing LDs as they measure and monitor the cells' metabolic function and droplets over time. Here, we present a novel machine-learning-based method for LDs analysis by segmentation of phase-contrast images of differentiated adipocytes (in vitro) and adipose tissue (in vivo). We developed a new workflow based on the ImageJ waikato environment for knowledge analysis segmentation plugin, which provides an accurate, label-free, live single-cell, and organelle quantification of LD-related parameters. By applying the new method on differentiating 3T3-L1 cells, the size of LDs was analyzed over time in differentiated adipocytes and their correlation with other morphological parameters. Moreover, we analyzed the LDs dynamics during catabolic changes such as lipolysis and lipophagy and demonstrated its ability to identify different cellular subpopulations based on their structural, numerical, and spatial variability. This analysis was also implemented on unstained ex vivo adipose tissues to measure adipocyte size, an important readout of the tissue's metabolism. The presented approach can be applied in different LD-related metabolic conditions to provide a better understanding of LD biogenesis and function in vivo and in vitro while serving as a new platform that enables rapid and accurate screening of data sets.

Tryptophan-kynurenine metabolism during acute alcohol withdrawal in patients with alcohol use disorder: The role of immune activation.

Recent research has suggested that excessive alcohol consumption in patients with alcohol use disorder (AUD) is associated with chronic immune activation, which affects the metabolism of the neurotransmitter precursor amino acid tryptophan (TRP) and contributes to the complex pathophysiology of AUD. Our study investigated possible immune-associated alterations of TRP to kynurenine (KYN) metabolism in patients with AUD during acute alcohol withdrawal. We measured serum concentrations of TRP, KYN, quinolinic (QUIN), kynurenic acid (KYNA), and the immune activation marker neopterin (NEO) at the first, fifth and 10th day of alcohol withdrawal in patients with AUD, who attended a standardized in-patient treatment program and underwent a detailed clinical assessment. Data from these individuals were compared to data from a reference control group (RCG). The primary outcome measures were the differences in serum concentrations of metabolites between AUD patients and RCG and correlations between NEO and metabolites of the tryptophan-kynurenine pathway. r=0.695, p < 0.001) in the AUD group. Mixed models analysis showed that NEO concentrations were positively associated with QUIN but not with KYNA concentrations. Several behavioral symptoms correlated positively with QUIN concentrations and negatively with the KYNA/QUIN ratio. Our findings demonstrate that the changes in TRP catabolism in acute alcohol withdrawal resulting in increased KYN production could reflect the involvement of immune-associated activation of the enzyme indoleamine 2,3-dioxygenase, as NEO concentrations correlated with the KYN/TRP ratio. In addition, our data show that this low-grade immune activation may cause an imbalance in the production of neurotoxic and neuroprotective kynurenine metabolites in AUD.

Heterogeneity in risk‐sensitive allocation of somatic reserves in a long‐lived mammal

AbstractFood quality and availability, when combined with energetic demands in seasonal environments, shape resource acquisition and allocation by animals and hold consequences for life‐history strategies. In long‐lived species with extensive maternal care, regulation of somatic reserves of energy and protein can occur in a risk‐sensitive manner, wherein resources are preferentially allocated to support survival at the cost of investment in reproduction. We investigated how Rocky Mountain bighorn sheep (Ovis canadensis), an alpine mammal in a highly seasonal environment, allocates somatic reserves across seasons. In accordance with the hypothesis of risk‐sensitive resource allocation, we expected accretion and catabolism of somatic reserves to be regulated relative to preseason nutritional state, reproductive state, and variation among populations in accordance with local environmental conditions. To test that hypothesis, we monitored seasonal changes in percent ingesta‐free body fat (IFBFat) and ingesta‐free, fat‐free body mass (IFFFBMass) in three populations of bighorn sheep in northwest Wyoming between 2015 and 2019 through repeated captures of female sheep in December and March of each year in a longitudinal study design. Regulation of somatic reserves was risk‐sensitive and varied relative to the amount of somatic reserves an animal had at the beginning of the season. Regulation of fat reserves was sensitive to reproductive state and differed by population, particularly over the summer. In one population with low rates of recruitment of young, sheep that recruited offspring lost fat over the summer in contrast to the other two populations where sheep that recruited gained fat. And yet, all populations exhibited similar changes in fat catabolism and risk sensitivity over winter. The magnitude of body fat and mass change across seasons may be indicative of sufficiency of seasonal ranges to meet energetic demands of survival and reproduction. Risk‐sensitive allocation of resources was pervasive, suggesting nutritional underpinnings are foundational to behavior, vital rates, and, ultimately, population dynamics. For species living in alpine environments, risk‐sensitive resource allocation may be essential to balance investment in reproduction with ensuring survival.

Proteomics study on the changes in amino acid metabolism during broccoli senescence induced by elevated O2 storage

To better understand the global changes of amino acid catabolism and anabolism in broccoli in response to high O2 stress, iTRAQ-based proteomics combined with amino acid analysis was used to investigate the broccoli proteome at 0 and 4 d after treatment with different O2 concentrations (5% O2 + 5% CO2, 20% O2 + 5% CO2 and 40% O2 + 5% CO2) at 20℃. A total of 106 proteins with changes ≥ 1.2-fold in abundance were observed. Amino acid anabolism was significantly suppressed by high O2 stress, while catabolism was enhanced. High O2 stress-induced amino acid metabolism promoted the conversion of Met to ethylene and the degradation of amino acids to intermediate metabolites of the TCA cycle, thereby suppressing glucosinolate biosynthesis. However, the up-regulation of arginase and urease induced by high O2 stress aggravated ammonium toxicity. These findings enhance our understanding of high O2 stress-induced amino acid metabolism, as well as the effects of amino acid metabolism on broccoli senescence.