The present study aimed to investigate the effects of eccentric treadmill exercise on adaptive hypertrophy of skeletal muscle in rats. Thirty-two 3-month-old Sprague Dawley (SD) rats were selected and randomly assigned to one of the four groups based on their body weights: 2-week quiet control group (2C), 2-week downhill running exercise group (2E), 4-week quiet control group (4C), and 4-week downhill running exercise group (4E). The downhill running protocol for rats in the exercise groups involved slope of -16°, running speed of 16 m/min, training duration of 90 min, and 5 training sessions per week. Twenty-four hours after the final session of training, all the four groups of rats underwent an exhaustion treadmill exercise. After resting for 48 h, all the rats were euthanized and their gastrocnemius muscles were harvested for analysis. HE staining was used to measure the cross-sectional area (CSA) and diameter of muscle fibers. Transmission electron microscope was used to observe the ultrastructural changes in muscle fibers. Purithromycin surface labeling translation method was used to measure protein synthesis rate. Immunofluorescence double labeling was used to detect the colocalization levels of lysosomal-associated membrane protein 2 (Lamp2)-leucyl-tRNA synthetase (LARS) and Lamp2-mammalian target of rapamycin (mTOR). Western blot was used to measure the protein expression levels of myosin heavy chain (MHC) IIb and LARS, as well as the phosphorylation levels of mTOR, p70 ribosomal protein S6 kinase (p70S6K), and eukaryotic translation initiation factor 4E binding protein 1 (4E-BP1). The results showed that, compared with the 2C group rats, the 2E group rats showed significant increases in wet weight of gastrocnemius muscle, wet weight/body weight ratio, running distance, running time, pre- and post-exercise blood lactate levels, myofibrillar protein content, colocalization levels of Lamp2-LARS and Lamp2-mTOR, and LARS protein expression. Besides these above changes, compared with the 4C group, the 4E group further exhibited significantly increased fiber CSA, fiber diameter, protein synthesis rate, and phosphorylation levels of mTOR, p70S6K, and 4E-BP1. Compared with the quiet control groups, the exercise groups exhibited ultrastructural damage of rat gastrocnemius muscle, which was more pronounced in the 4E group. These findings suggest that eccentric treadmill exercise may promote mTOR translocation to lysosomal membrane, activating mTOR signaling via up-regulating LARS expression. This, in turn, increases protein synthesis rate through the mTOR-p70S6K-4E-BP1 signaling pathway, promoting protein deposition and inducing adaptive skeletal muscle hypertrophy. Although the ultrastructural changes of skeletal muscle are more pronounced, the relatively long training cycles during short-term exercise periods have a more significant effect on promoting gastrocnemius muscle protein synthesis and adaptive hypertrophy.
Animals ; Rats, Sprague-Dawley ; Physical Conditioning, Animal/physiology* ; Rats ; Muscle, Skeletal/metabolism* ; TOR Serine-Threonine Kinases/metabolism* ; Male ; Hypertrophy ; Adaptation, Physiological/physiology* ; Adaptor Proteins, Signal Transducing/metabolism* ; Ribosomal Protein S6 Kinases, 70-kDa/metabolism* ; Intracellular Signaling Peptides and Proteins

The balance between growth and defense in response to nearby or canopy shading in heliotropic plants has been deeply understood. However, the adaptive traits developed by shade-tolerant plants through long-term evolution remain unclear. In this study, the typical shade-tolerant medicinal plant Anoectochilus roxburghii was used as the experimental material.(1) Different planting densities were set, including 8 cm(row spacing) × 8 cm(plant spacing), 6 cm × 6 cm, 4 cm × 4 cm, and 2 cm × 2 cm, to monitor the individual plant responses to nearby shading.(2) Different light environments, including blue light∶red light=3∶2(B3R2), blue light∶red light∶far-red light=3∶2∶1(B3R2FR1), blue light∶red light∶far-red light=3∶2∶2(B3R2FR2), and blue light∶red light∶far-red light=3∶2∶4(B3R2FR4), were set to monitor the morphological and physiological changes in plants in response to actual shading conditions. The results showed that:(1) Moderate increases in planting density helped optimize morphological traits such as stem diameter and leaf area. This not only slightly increased biomass but also significantly improved SOD activity in both leaves and stems, as well as lignin content in stems, thereby enhancing the plant's defense capabilities.(2) Increasing the far-red light in the light environment negatively regulated the plant height of A. roxburghii, which was contrary to the typical shade-avoidance response observed in heliotropic plants. However, it significantly enhanced SOD and POD activity in both stems and leaves, as well as lignin content in stems. Furthermore, it reduced the incidence and disease index of stalk rot, effectively defending against biotic stress. Therefore, the shade-tolerant plant A. roxburghii has specific adaptive strategies for shading conditions. Reasonable dense planting or light environment modulation can synergistically improve yield, medicinal quality, and resistance of A. roxburghii. This study provides a theoretical foundation and technical support for optimizing the regional deployment and cultivation strategies of ecological planting for Chinese medicinal materials.
Orchidaceae/genetics* ; Light ; Plant Leaves/physiology* ; Sunlight ; Adaptation, Physiological/radiation effects* ; Plant Proteins/genetics*

OBJECTIVES: This study aims to investigate the impact of glutathione S-transferase (GST) on the environmental adaptability of Streptococcus mutans (S. mutans). METHODS: A GST knockout strain ΔgsT was constructed. Transcriptomic sequencing was performed to analyze the gene expression differences between the wild-type S. mutans UA159 and its GST knockout strain ΔgsT. Comprehensive functional assessments, including acid tolerance assays, hydrogen peroxide challenge assays, nutrient limitation growth assays, and fluorescence in situ hybridization, were conducted to evaluate the acid tolerance, antioxidant stress resistance, growth kinetics, and interspecies competitive ability of ΔgsT within plaque biofilms. RESULTS: Compared with the wild-type S. mutans, 198 genes in ΔgsT were significantly differentially expressed and enriched in pathways related to metabolism, stress response, and energy homeostasis. The survival rate of ΔgsT in acid tolerance assays was markedly reduced (P<0.01). After 15 min of hydrogen peroxide challenge, the survival rate of ΔgsT decreased to 38.12% (wild type, 71.75%). Under nutrient-limiting conditions, ΔgsT exhibited a significantly lower final OD₆₀₀ value than the wild-type strain (P<0.05). In the biofilm competition assays, the proportion of S. mutans ΔgsT in the mixed biofilm (8.50%) was significantly lower than that of the wild type (16.89%) (P<0.05). CONCLUSIONS GST enhances the acid resistance, oxidative stress tolerance, and nutrient adaptation of S. mutans by regulating metabolism-related and stress response-related genes.
Streptococcus mutans/enzymology* ; Biofilms ; Glutathione Transferase/physiology* ; Adaptation, Physiological ; Hydrogen Peroxide/pharmacology* ; Gene Expression Regulation, Bacterial ; Oxidative Stress ; Metabolic Reprogramming

The ability of cells to sense and adapt to metabolic changes and environmental variations is essential for their functions. Recent advances in synthetic biology have uncovered increasing mechanisms through which cells detect changes in metabolism and environmental conditions, leading to broader applications. However, a systematic review on the regulation of cellular metabolism and environmental adaption is currently lacking. This article presents a comprehensive overview of this field from three perspectives. First, it introduces key transmembrane and sensor proteins involved in the cellular perception of metabolic and environmental changes. Next, it summarizes the adaptive regulation mechanisms that natural cells employ when confronted with intracellular and extracellular metabolic changes. Finally, the review explores the application scenarios based on cellular adaptive regulation in three aspects: dynamic control, rational metabolic engineering, and adaptive evolution and makes an outlook on the future development directions in this field. This review not only provides a comprehensive perspective on the mechanisms by which cells sense metabolic and environmental variations, but also lays a theoretical foundation for further innovations in the field of synthetic biology. With the continuous advancement of future technologies, a deeper understanding of cellular adaptive regulation mechanisms holds great potential to drive the development and application of novel biomanufacturing platforms.
Adaptation, Physiological ; Synthetic Biology ; Metabolic Engineering/methods* ; Environment ; Bacteria/genetics*

The aluminum stress in acidic soil areas of China is an important abiotic stress factor that hampers the normal growth and development of plants and seriously affects the agricultural yield. The forms of plant resistance to aluminum stress are complex and diverse, which include secretion of organic acids, increase of rhizosphere pH, secretion of mucus, cell wall fixation of Al³⁺, organic acid chelation of Al³⁺ in cell solute, and vacuolar area isolation. Most of studies focus on analyzing conventional physiological characteristics, but in-depth molecular biological analyses are lacking. This review summarizes the mechanisms how plants adapt to acidic aluminum stress. This includes the effect of acid aluminum stress on plant growth and physiological metabolism, the two main physiological mechanisms of plant adaptation to acid aluminum stress (aluminum exclusion mechanism, aluminum tolerance mechanism), and the aluminum resistance related genes. Finally, this paper puts forward some prospects for further revealing the mechanism of plant adaptation to acid aluminum stress and excavating high-quality crops suitable for cultivation in acidic soils.
Acids ; Adaptation, Physiological ; Aluminum ; Crops, Agricultural/genetics* ; Gene Expression Regulation, Plant ; Plant Roots ; Soil/chemistry*

Intestinal adaptation is a spontaneous compensation of the remanent bowel after extensive enterectomy, which improves the absorption capacity of the remanent bowel to energy, fluid and other nutrients. Intestinal adaptation mainly occurs within 2 years after enterectomy, including morphological changes, hyperfunction and hyperphagia. Intestinal adaptation is the key factor for patients with short bowel syndrome to weaning off parenteral nutrition dependence and mainly influenced by length of remanent bowel, type of surgery and colon continuity. In addition, multiple factors including enteral feeding, glucagon-like peptide 2 (GLP-2), growth hormone, gut microbiota and its metabolites regulate intestinal adaptation via multi-biological pathways, such as proliferation and differentiation of stem cell, apoptosis, angiogenesis, nutrients transport related protein expression, gut endocrine etc. Phase III clinical trials have verified the safety and efficacy of teduglutide (long-acting GLP-2) and somatropin (recombinant human growth hormone) in improving intestinal adaptation, and both have been approved for clinical use. We aim to review the current knowledge about characteristics, mechanism, evaluation methods, key factors, clinical strategies of intestinal adaptation.
Humans ; Adaptation, Physiological ; Glucagon-Like Peptide 2/therapeutic use* ; Intestines/surgery* ; Parenteral Nutrition ; Short Bowel Syndrome/surgery*

Adaptation, Physiological ; Adenosine Monophosphate ; administration & dosage ; analogs & derivatives ; pharmacology ; therapeutic use ; Administration, Intranasal ; Alanine ; administration & dosage ; analogs & derivatives ; pharmacology ; therapeutic use ; Animals ; Betacoronavirus ; genetics ; physiology ; Chlorocebus aethiops ; Coronavirus Infections ; drug therapy ; virology ; Disease Models, Animal ; Female ; Host Specificity ; genetics ; Lung ; pathology ; virology ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Mutation, Missense ; Nasal Mucosa ; virology ; Pandemics ; Pneumonia, Viral ; drug therapy ; virology ; RNA, Viral ; administration & dosage ; genetics ; Turbinates ; virology ; Vero Cells ; Viral Load ; Virus Replication

PURPOSE: To identify needs for pregnancy and postpartum adaptation of Chinese immigrant women and Vietnamese immigrant women in South Korea. METHODS: A descriptive research design was employed. Data were collected from 244 Chinese immigrant women and Vietnamese immigrant women from 3 provinces, 20 health care centers, and multi-cultural family support centers. Data were analyzed with descriptive statistics, t-test and ANOVA. RESULTS: An average score for needs perceived by Chinese immigrant women was significantly higher than that perceived by Vietnamese immigrant women. There were significantly differences in physical and emotional adaptation after childbirth, nutrition during pregnancy, cross cultural understanding and personal respect, and adaptation daily activity during pregnancy between the 2 groups. The highest score of needs in Chinese immigrant women was for nutrition during pregnancy and that in Vietnamese immigrant women was for baby rearing and family support. CONCLUSION: Based on needs of pregnancy and postpartum adaption, nursing intervention program in consideration of cultural characteristics of Chinese immigrant women and Vietnam immigrant women need to be developed for their pregnancy and postpartum health care.
Adaptation, Physiological ; Asian Continental Ancestry Group ; Cultural Characteristics ; Delivery of Health Care ; Emigrants and Immigrants ; Emotional Adjustment ; Female ; Humans ; Korea ; Needs Assessment ; Nursing ; Parturition ; Postpartum Period ; Pregnancy ; Prenatal Nutritional Physiological Phenomena ; Research Design ; Vietnam

The human capacity for physiologic adaptation to cold is minimal. A cold environment can be a threat to the skin, leading to a subsequent fall in core body temperature. Many physiologic, behavioral, and environmental factors predispose to the global effects of cold injuries. Physical injuries caused by cold have two forms: systemic forms such as hypothermia and localized forms such as frostbite. Reduced temperature directly damages the tissue, as in frostbite and cold immersion foot. Vasospasm of vessels perfusing the skin induces chilblain, acrocyanosis, and frostbite. The degree of damage caused by cold is related to four factors: temperature, exposure time, wind intensity (temperature sensation), and high altitude.
Adaptation, Physiological ; Altitude ; Body Temperature ; Chilblains ; Cold Injury ; Frostbite ; Humans ; Hypothermia ; Immersion Foot ; Skin ; Wind

In industrial fermentation processes, bacteria have to adapt environmental stresses. Sometimes, such a self-adaption does not work and will cause fermentation failures, although such adaptation also can generate unexpected positive effects with improved fermentation performance. Our review introduces cell self-adaption to environmental variations or stress, process optimization based on such self-adaptions, with heterologous proteins production by Pichia pastoris and butanol fermentation as examples. Our review can sever as reference for fermentation optimization based on cell self-adaption.
Adaptation, Physiological ; Butanols ; metabolism ; Environment ; Fermentation ; Pichia ; cytology ; metabolism