Search bioRxiv⌕ Search

SEARCH · Search bioRxiv

Results for “Physiology”

Search indexed bioRxiv preprints in genomics, neuroscience, cell biology and bioinformatics. Read source abstracts and check manuscript versions; preprints are not peer reviewed.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,117 records · Page 62Linked to original sources

Contrasting behavioral and physiological effects of Gtf2i duplication and deletion in mouse models of the 7q11.23 Duplication and Williams-Beuren Syndromes

7q11.23 Microduplication Syndrome (7Dup) and Williams-Beuren Syndrome (WBS) are two ASD-related syndromes characterized by both common and contrasting symptoms, caused by either duplication or deletion of a 1.5-1.8 Mb segment in section q11.23 of Human chromosome 7, respectively. Notably, WBS patients show reduced social fear and are considered hyper-social, while 7Dup patients suffer from social anxiety and withdrawal. Previous work suggests that the GTF2I gene, one of the genes included in this segment, has a major role in the social symptoms of both syndromes. Here, we combine video and thermal imaging in multiple social behavior tests to screen for behavioral and physiological variables showing variations in mice models with either a duplication (Gtf2i+/dup) or a deletion (Gtf2i+/del) of the gene. Our analyses of social behavior, micturition, and defecation patterns identify several differences between wild-type and mutant littermates, some of which show contrasting variations associated with Gtf2i dosage. Interestingly, thermal imaging revealed that Gtf2i dosage dictates the mices surface temperature profile during the tests, with Gtf2i+/dup males exhibiting higher surface temperature than their wild-type littermates, while Gtf2i+/del males and females show the opposite tendency. These results suggest that the two mouse models exhibit opposite changes in either their emotional state or thermoregulation capabilities, in correlation with Gtf2i dosage.

neuroscience↗

Predicting Real-life Drinking Scenarios through a Physiological Digital Twin Incorporating Secondary Alcohol Markers

Alcohol consumption poses significant societal challenges, necessitating accurate tools for detecting at-risk drinking. Various biomarkers reflect alcohol intake over different timeframes. Blood alcohol concentration (BAC) and breath alcohol concentration (BrAC) are commonly used for short-term detection, particularly in forensic contexts such as driving under the influence of alcohol (DUIA) cases. Moreover, the rapid kinetics of BAC and BrAC limit their utility in determining the precise timing of intake--an essential factor in legal cases involving defenses like the hipflask argument. To address this, secondary metabolites including ethyl glucuronide (EtG), ethyl sulphate (EtS), and urine alcohol concentration (UAC) offer slower, more time-sensitive profiles. Combining these markers could enable a more accurate reconstruction of past alcohol consumption events. Traditionally, mathematical models have been used to help extract information from the dynamics of alcohol-related markers. Existing mathematical models typically focus on primary markers or single secondary markers in isolation. In this study, we present an extended mathematical model that integrates all markers; BAC, EtG, EtS, and UAC into a unified framework, expanding our previous physiological twin model. Our updated model enables personalized simulations of alcohol metabolism and intake timing, which in turn creates the fundament for enhancing forensic assessments and supporting applications where accurate temporal analysis of alcohol consumption is critical. To facilitate accessibility and practical use of this analysis, we have implemented and provided an interactive web application.

systems biology↗

Optimizing Cancer Vaccinations Using a Physiologically Based Pharmacokinetic (PBPK) Model

Antigen-based tumor vaccines rely on adjuvants to stimulate local inflammation, recruit antigen-presenting cells (APCs), and enhance immune activation. However, the complex interplay between antigen transport, lymphatic drainage, and immune cell dynamics across organs remains poorly understood, limiting the rational design of vaccination strategies. Here, we present a multiscale compartmental Physiologically Based Pharmacokinetic (PBPK) model of antigen vaccination that integrates systemic circulation, lymphatic connectivity, and immune cell activation at the whole-body level. The model incorporates arterial, venous, and lymphatic flows, organ-specific interstitium and lymph node (LN) networks, and a superficial skin network. The model reproduces spatiotemporal distributions of antigen and suppressive factors, APC activation, and nT priming across activation sites, including LNs and spleen. Our results show that the sensitivity of vaccination-induced immunity is highly related to antigen and suppressive factor production by the tumor, and that early-stage vaccination, enhances immunity. Since the model is able to identify optimal vaccination administration over the course of tumor growth for each patient with certain levels of antigen and immune suppressive factors, it can serve as the foundation for digital twins of patients to help inform anti-cancer vaccination strategies. TeaserA PBPK model links body-wide immune transport to optimize cancer vaccine design and delivery.

systems biology↗

Chronotype-specific impacts of sleep-wake schedule on behavioral, physiological and psychological parameters

Diurnal variations in human performance are known to be associated with chronotype, which reflects individual differences in preferred sleep-wake cycles. Early chronotypes (ECs) exhibit superior motor and cognitive functions in the morning, whereas late chronotypes (LCs) tend to perform better in the evening. However, previous studies have examined these patterns under socially imposed nighttime sleep schedules, without considering individuals preferred sleep timing. Thus, it remains unclear whether these chronotype-dependent performance peaks persist when individuals follow their preferred sleep schedules. To address this question, we measured subjective states, sleep pressure (using electroencephalography), and motor and cognitive functions at 1.5 and 12.5 hours after awakening under two conditions: the Clock-Time condition (10:30 PM-6:30 AM sleep aligned with social rhythms) and the Self-Time condition (8 hours of sleep aligned with individual preferences). The results revealed distinct chronotype-specific patterns. ECs exhibited increases in fatigue and sleepiness dependent on awake duration, showing typical sleep pressure accumulation. LCs were more affected by sleep timing and showed atypical patterns of sleep pressure accumulation compared with ECs. Motor ability tended to improve in the afternoon in both chronotypes, irrespective of sleep-wake schedule, whereas cognitive performance peaked at different stages of wakefulness - earlier for ECs and later for LCs - independent of the time of day. These findings suggest that chronotype-aligned sleep-wake schedules could help optimize fatigue management, cognitive performance, and motor control. Diurnal variations in performance cannot be attributed to clock time alone but emerge from the combined effects of chronotype, awake duration, and sleep-wake regulation. Statement of SignificanceThis study provides new insights into the ways in which chronotype and sleep-wake schedules jointly shape behavioral, physiological, and psychological dynamics across the day. Whereas previous research has largely emphasized circadian rhythms, our findings underscore the critical role of actual sleep timing in modulating daily function ing. This integrative perspective extends current understanding of the ways in which individual differences in biological timing and social constraints interact to influence human health and performance. Importantly, the results highlight the need for future studies to disentangle circadian and sleep-wake schedule effects, which could inform personalized strategies for optimizing well-being, productivity, and clinical interventions in disorders related to sleep and circadian misalignment.

neuroscience↗

Correlation of gene expressions between nucleus and cytoplasm reflects single-cell physiology

BackgroundEukaryotes transcribe RNAs in nuclei and transport them to the cytoplasm through multiple steps of post-transcriptional regulation. Existing single-cell sequencing technologies, however, are unable to analyse nuclear (nuc) and cytoplasmic (cyt) RNAs separately and simultaneously. Hence, there remain challenges to discern correlation, localisation, and translocation between them.\n\nResultsHere we report a microfluidic system that physically separates nucRNA and cytRNA from a single cell and enables single-cell integrated nucRNA and cytRNA-sequencing (SINC-seq). SINC-seq constructs two individual RNA-seq libraries, nucRNA and cytRNA per cell, quantifies gene expression in the subcellular compartments and combines them to create a novel single-cell RNA-seq data enabled by our system, which we here term in-silico single cell.\n\nConclusionsLeveraging SINC-seq, we discovered three distinct natures of correlation among cytRNA and nucRNA that reflected the physiological state of single cells: The cell-cycle-related genes displayed highly correlated expression pattern with minor differences; RNA splicing genes showed lower nucRNA-to-cytRNA correlation, suggesting a retained intron may be implicated in inhibited mRNA transport; A chemical perturbation, sodium butyrate treatment, transiently distorted the correlation along differentiating human leukemic cells to erythroid cells. These data uniquely provide insights into the regulatory network of mRNA from nucleus toward cytoplasm at the single cell level.

genomics↗

White matter haemodynamics: basic physiology and disruption in neuroinflammatory disease

The white matter is highly vascularised by the cerebral venous system. The neuroinflammatory disease multiple sclerosis is associated with infiltration of peripheral immune cells into the brain via these vessels. Understanding venous pathophysiology in multiple sclerosis is thus critical for understanding early disease aetiology. In this paper, we describe a unique blood oxygen-level dependent (BOLD) signal within the white matter using functional MRI and spatial independent components analysis, a blind signal source separation method. The signal was characterised by a narrow peak frequency band between 0.05 and 0.1 Hz. Hypercapnia (transient breath holds), known to alter venous calibre in cortex, induced transient increases in white matter BOLD that disrupted the oscillation indicative of a vasodilatory/contractile mechanism. Comparison of the white matter BOLD oscillations between age and sex matched groups of 18 multiple sclerosis and 14 healthy participants revealed a loss of power in the white matter BOLD signal in the peak frequency band (patients = 6.70{+/-}0.94 dB/Hz vs controls = 7.64{+/-}0.71 dB/Hz; p=0.006). In multiple sclerosis patients, lower power was associated with greater levels of neuroinflammatory activity (R=-0.64, p=0.006) but not neurodegenerative disease markers. Using a signal modelling technique, we assessed the anatomical distribution of white matter BOLD signal abnormalities and detected reduced power in the periventricular white matter, a region of known venous damage in multiple sclerosis patients. These results demonstrate a novel link between neuroinflammation and vascular physiological dysfunction in the cerebral white matter, and could indicate enduring loss of vascular compliance associated with imperfect repair of blood-brain barrier damage after resolution of acute neuroinflammation.

neuroscience↗

The physiological regulation of macropinocytosis during Dictyostelium growth and development

Macropinocytosis is a conserved endocytic process used by Dictyostelium amoebae for feeding on liquid medium. To further Dictyostelium as a model for macropinocytosis, we developed a high-throughput flow cytometry assay for macropinocytosis, and used it to identify inhibitors and investigate the physiological regulation of macropinocytosis. Dictyostelium has two feeding states: phagocytic and macropinocytic. When cells are switched from phagocytic growth on bacteria to liquid media, the rate of macropinocytosis slowly increases, due to increased size and frequency of macropinosomes. Upregulation is triggered by a minimal medium of 3 amino acids plus glucose and likely depends on macropinocytosis itself. Bacteria suppress macropinocytosis while their product, folate, partially suppresses upregulation of macropinocytosis. Starvation, which initiates development, does not of itself suppress macropinocytosis: this can continue in isolated cells, but is shut down by a conditioned-medium factor or activation of PKA signalling. Thus macropinocytosis is a facultative ability of Dictyostelium cells, regulated by environmental conditions that are identified here.\n\nSummaryA high-throughput flow cytometry assay shows that macropinocytosis in D. discoideum is upregulated in the presence of nutrients and absence of bacteria. Development and bacteria induce cells to downregulate macropinocytosis.

microbiology↗

Variation in physiological function across source populations of a New Zealand freshwater snail

Mitochondrial function is critical for energy homeostasis and should shape how genetic variation in metabolism is transmitted through levels of biological organization to generate stability in organismal performance. Mitochondrial function is encoded by genes in two distinct and separately inherited genomes - the mitochondrial genome and the nuclear genome - and selection is expected to maintain functional mito-nuclear interactions. Nevertheless, high levels of polymorphism in genes involved in these mito-nuclear interactions and variation for mitochondrial function are nevertheless frequently observed, demanding an explanation for how and why variability in such a fundamental trait is maintained. Potamopyrgus antipodarum is a New Zealand freshwater snail with coexisting sexual and asexual individuals and, accordingly, contrasting systems of separate vs. co-inheritance of nuclear and mitochondrial genomes. As such, this snail provides a powerful means to dissect the evolutionary and functional consequences of mito-nuclear variation. The lakes inhabited by P. antipodarum span wide environmental gradients, with substantial across-lake genetic structure and mito-nuclear discordance. This situation allows us to use comparisons across reproductive modes and lakes to partition variation in cellular respiration across genetic and environmental axes. Here, we integrated cellular, physiological, and behavioral approaches to quantify variation in mitochondrial function across a diverse set of wild P. antipodarum lineages. We found extensive across-lake variation in organismal oxygen consumption, mitochondrial membrane potential, and behavioral response to heat stress, but few global effects of reproductive mode or sex. Taken together, our data set the stage for applying this important model system for sexual reproduction and polyploidy to dissecting the complex relationships between mito-nuclear variation, performance, plasticity, and fitness in natural populations.

evolutionary biology↗

Physiological and transcriptional response of the diatom Corethron hystrix under robust UVR irradiation

The effect of ultraviolet radiation (UVR) on photosynthetic efficiency and the resulting mechanisms against UV exposure employed by phytoplankton are not completely understood. To address this knowledge gap, we developed a novel close-coupled, wavelength-configurable platform designed to produce precise and repeatable in vitro irradiation of Corethron hystrix, a member of a genera found abundantly in the Southern Ocean where UV exposure is high. We aimed to determine its metabolic, protective, mutative, and repair mechanisms as a function of varying levels of specific electromagnetic energy. Our results show that the physiological responses to each energy level of UV have a negative linear decrease in the photosynthetic efficiency of photosystem II proportional to UV intensity, corresponding to a large increase in the turnover time of quinone re-oxidation. Gene expression changes of photosystem II related reaction center proteins D1, CP43 and CP47 showed coordinated downregulation whereas the central metabolic pathway demonstrated mixed expression of up and downregulated transcripts after UVR exposure. These results suggest that while UVR may damage photosynthetic machinery, oxidative damage may limit production of new photosynthetic and electron transport complexes as a result of UVR exposure.

microbiology↗

Infection By A Giant Virus Induces Widespread Physiological Reprogramming In Aureococcus anophagefferens - A Harmful Bloom Algae

While viruses with distinct phylogenetic origins and different nucleic acid types can infect and lyse eukaryotic phytoplankton, \"giant\" dsDNA viruses have been found to be associated with important ecological processes, including the collapse of algal blooms. However, the molecular aspects of giant virus - host interactions remain largely unknown. AaV, a giant virus in the Mimiviridae clade, is known to play a critical role in regulating the fate of brown tide blooms caused by the pelagophyte Aureococcus anophagefferens. To understand the physiological response of A. anophagefferens CCMP1984 upon AaV infection, we studied the transcriptomic landscape of this host-virus pair over an entire infection cycle using a RNA-sequencing approach. A massive transcriptional reprogramming of the host was evident as early as 5 min post-infection, with modulation of specific processes likely related to both host defense mechanism(s) and viral takeover of the cell. Infected Aureococcus showed a relative suppression of host-cell transcripts associated with photosynthesis, cytoskeleton formation, fatty acid and carbohydrate biosynthesis. In contrast, host cell processes related to protein synthesis, polyamine biosynthesis, cellular respiration, transcription and RNA processing were overrepresented compared to the healthy cultures at different stages of the infection cycle. A large number of redox active host-selenoproteins were overexpressed, which suggested that viral replication and assembly progresses in a highly oxidative environment. The majority (99.2%) of annotated AaV genes were expressed at some point during the infection cycle and demonstrated a clear temporal-expression pattern and an increasing relative expression for the majority of the genes through the time course. We detected a putative early promoter motif for AaV, which was highly similar to the early promoter elements of two other Mimiviridae members, indicating some degree of evolutionary conservation of gene regulation within this clade. This large-scale transcriptome study provides the insight into the Aureococcus virocell, and establishes a foundation to test hypotheses regarding metabolic and regulatory processes critical for AaV and other Mimiviridae members.

microbiology↗

Anatomical, Physiological, and Functional Heterogeneity of the Dorsal Raphe Serotonin System

The dorsal raphe (DR) constitutes a major serotonergic input to the forebrain, and modulates diverse functions and brain states including mood, anxiety, and sensory and motor functions. Most functional studies to date have treated DR serotonin neurons as a single, homogeneous population. Using viral-genetic methods, we found that subcortical-vs. cortical-projecting serotonin neurons have distinct cell body distributions within the DR and different degrees of coexpressing a vesicular glutamate transporter. Further, the amygdala-and frontal cortex-projecting DR serotonin neurons have largely complementary whole-brain collateralization patterns, receive biased inputs from presynaptic partners, and exhibit opposite responses to aversive stimuli. Gain-and loss-of-function experiments suggest that amygdala-projecting DR serotonin neurons promote anxiety-like behavior, whereas frontal cortex-projecting neurons promote active coping in face of challenge. These results provide compelling evidence that the DR serotonin system contains parallel sub-systems that differ in input and output connectivity, physiological response properties, and behavioral functions.

neuroscience↗

Gut microbiota density influences host physiology and is shaped by host and microbial factors

To identify factors that regulate gut microbiota density and the impact of varied microbiota density on health, we assayed this fundamental ecosystem property in fecal samples across mammals, human disease, and therapeutic interventions. Physiologic features of the host (carrying capacity) and the fitness of the gut microbiota shape microbiota density. Therapeutic manipulation of microbiota density in mice altered host metabolic and immune homeostasis. In humans, gut microbiota density was reduced in Crohns disease, ulcerative colitis, and ileal pouch-anal anastomosis. The gut microbiota in recurrent Clostridium difficile infection had lower density and reduced fitness that were restored by fecal microbiota transplantation. Understanding the interplay between microbiota and disease in terms of microbiota density, host carrying capacity, and microbiota fitness provide new insights into microbiome structure and microbiome targeted therapeutics.

microbiology↗

Disabling Gβγ SNARE interaction in transgenic mice disrupts GPCR-mediated presynaptic inhibition leading to physiological and behavioral phenotypes.

Gi/o-coupled G-protein coupled receptors modulate neurotransmission presynaptically through inhibition of exocytosis. Release of G{beta}{gamma} subunits decreases the activity of voltage-gated calcium channels (VGCC), decreasing excitability. A less understood G{beta}{gamma}-mediated mechanism downstream of calcium entry is the binding of G{beta}{gamma} to SNARE complexes. Here, we create a mouse partially deficient in this interaction. SNAP25{Delta}3 homozygote animals are developmentally normalbut impaired gait and supraspinal nociception. They also have elevated stress-induced hyperthermia and impaired inhibitory postsynaptic responses to 2A-AR, but normal inhibitory postsynaptic responses to Gi/o-coupled GABAB receptor activation. SNAP25{Delta}3 homozygotes have deficits in inhibition of hippocampal postsynaptic responses to 5 HT1b agonists that affect hippocampal learning. These data suggest that Gi/o-coupled GPCR inhibition of exocytosis through the G{beta}{gamma}-SNARE interaction is a crucial component of numerous physiological and behavioral processes.

neuroscience↗

Physiological Significance of R-fMRI Indices in Detecting Structural Brain Lesions

Resting-state functional MRI (R-fMRI) research has recently entered the era of \"big data\", however, few studies have provided a rigorous validation of the physiological underpinnings of R-fMRI indices. Although studies have reported that various neuropsychiatric disorders exhibit abnormalities in R-fMRI measures, these \"biomarkers\" have not been validated in differentiating structural lesions (brain tumors) as a concept proof. We enrolled 60 patients with intracranial tumors located in the unilateral cranial cavity and 60 matched normal controls to test whether R-fMRI indices can differentiate tumors, which represents a prerequisite for adapting such indices as biomarkers for neuropsychiatric disorders. Common R-fMRI indices of tumors and their counterpart control regions, which were defined as the contralateral normal areas (for amplitude of low frequency fluctuations (ALFF), fractional ALFF (fALFF), regional homogeneity (ReHo) and degree centrality (DC)) and ipsilateral regions surrounding the tumors (for voxel-mirrored homotopic connectivity (VMHC)), were comprehensively assessed. According to paired t-tests with a Bonferroni correction, only ALFF (both with and without Z-standardization) and VMHC (Fishers r-to-z transformed) could successfully differentiate substantial tumors from their counterpart normal regions in patients. And DC was not able to differentiate tumor from normal unless employed Z-standardization. To validate the lower power in the between-subject design than in the within-subject design, each metric was calculated in a matched control group, and two-sample t-tests were used to compare the patient tumors and the normal controls at the same area. Only ALFF (and that with Z-standardization) along with VMHC succeeded in differentiating significant differences between tumors and the sham tumors areas of normal controls. This study tested the premise of R-fMRI biomarkers for differentiating lesions, and brings a new understanding to physical significance of the Z-standardization.

neuroscience↗

Whole-brain calcium imaging during physiological vestibular stimulation in larval zebrafish

During in vivo functional imaging, animals are head-fixed and thus deprived from vestibular inputs, which severely hampers the design of naturalistic virtual environments. To overcome this limitation, we developed a miniaturized ultra-stable light-sheet microscope that can be dynamically rotated during imaging along with a head-restrained zebrafish larva. We demonstrate that this system enables whole-brain functional imaging at single-cell resolution under controlled vestibular stimulation. We recorded for the first time the dynamic whole-brain response of a vertebrate to physiological vestibular stimulation. This development largely expands the potential of virtual-reality systems to explore complex multisensory-motor integration in 3D.

neuroscience↗

Physiological starvation increases EGF-Ras-MAPK pathway activity during C. elegans vulval induction

Studying how molecular pathways respond to ecologically relevant environmental variation is fundamental to understand organismal development and its evolution. Here we characterize how starvation modulates Caenorhabditis elegans vulval cell fate patterning - an environmentally sensitive process, with a nevertheless robust output. Past research has shown many vulval mutants affecting EGF-Ras-MAPK, Delta-Notch and Wnt pathways to be suppressed by environmental factors, such as starvation. Here we aimed to resolve previous, seemingly contradictory, observations on how starvation modulates levels of vulval induction. Using the strong starvation suppression of the Vulvaless phenotype of lin-3/egf reduction-of-function mutations as an experimental paradigm, we first tested for a possible involvement of the sensory system in relaying starvation signals to affect vulval induction: mutation of various sensory inputs, DAF-2/Insulin or DAF-7/TGF-{beta} signaling did not abolish lin-3(rf) starvation suppression. In contrast, nutrient deprivation induced by mutation of the intestinal peptide transporter gene pept-1 or the TOR pathway component rsks-1 (the orthologue of mammalian P70S6K) very strongly suppressed lin-3(rf) mutant phenotypes. Therefore, physiologically starved animals induced by these mutations tightly recapitulated the effects of external starvation on vulval induction. While both starvation and pept-1 RNAi were sufficient to increase Ras and Notch pathway activities in vulval cells, the highly penetrant Vulvaless phenotype of a tissue-specific null allele of lin-3 was not suppressed by either condition. This and additional results indicate that partial lin-3 expression is required for starvation to affect vulval induction. These results suggest a cross-talk between nutrient deprivation, TOR-S6K and EGF-Ras-MAPK signaling during C. elegans vulval induction.

genetics↗

A large-scale, standardized physiological survey reveals higher order coding throughout the mouse visual cortex

To understand how the brain processes sensory information to guide behavior, we must know how stimulus representations are transformed throughout the visual cortex. Here we report an open, large-scale physiological survey of neural activity in the awake mouse visual cortex: the Allen Brain Observatory Visual Coding dataset. This publicly available dataset includes cortical activity from nearly 60,000 neurons collected from 6 visual areas, 4 layers, and 12 transgenic mouse lines from 221 adult mice, in response to a systematic set of visual stimuli. Using this dataset, we reveal functional differences across these dimensions and show that visual cortical responses are sparse but correlated. Surprisingly, responses to different stimuli are largely independent, e.g. whether a neuron responds to natural scenes provides no information about whether it responds to natural movies or to gratings. We show that these phenomena cannot be explained by standard local filter-based models, but are consistent with multi-layer hierarchical computation, as found in deeper layers of standard convolutional neural networks.

neuroscience↗

Physiological Dynamic Compression Regulates Central Energy Metabolism in Primary Human Chondrocytes

Chondrocytes use the pathways of central metabolism to synthesize molecular building blocks and energy for cartilage homeostasis. An interesting feature of the in vivo chondrocyte environment is the cyclical loading generated in various activities (e.g. walking). However, it is unknown if central metabolism is altered by mechanical loading. We hypothesized that physiological dynamic compression alters central metabolism in chondrocytes to promote production of amino acid precursors for matrix synthesis. We measured the expression of central metabolites (e.g. glucose, its derivatives, and relevant co-factors) for primary human osteoarthritic chondrocytes in response to 0-30 minutes of compression. To analyze the data, we used principal components analysis and ANOVA simultaneous components analysis, as well as metabolic [fl]ux analysis. Compression induced metabolic responses consistent with our hypothesis. Additionally, these data show that chondrocyte samples from different patient donors exhibit different sensitivity to compression. Most important, we [fi]nd that grade IV osteoarthritic chondrocytes are capable of synthesizing non-essential amino acids and precursors in response to mechanical loading. These results suggest that further advances in metabolic engineering of chondrocyte mechanotransduction may yield novel translational strategies for cartilage repair.

systems biology↗