Search Results (1,070)

Background: Mixed martial arts (MMA) involve repeated high-intensity, explosive actions that cause substantial fatigue, underscoring the importance of effective recovery strategies. Purpose: This pilot study investigated short-term performance responses to different post-exercise recovery interventions in Polish MMA athletes. Methods: Sixteen athletes (14 males and 2 females) were randomly assigned to cryosauna (CRYO), cold-water immersion (CWI), foam rolling (FR), or passive recovery (CON), with 4 participants per group. The intervention lasted two weeks, with the assigned recovery intervention applied after each training session. Performance was evaluated before and after the intervention using the countermovement jump (CMJ), isokinetic knee peak torque (flexion and extension), and reactive stress tolerance of the determination test (DT). Data were analyzed using mixed-design ANOVA. Results: CMJ performance improved over time across groups. FR significantly increased knee extension (from 228.67 ± 26.49 N.m to 250.50 ± 22.41 N.m), whereas DT scores significantly increased in the CRYO group (from 247.50 ± 12.50 AU to 291.50 ± 15.61 AU) and significantly decreased in the CON group (from 290.25 ± 24.45 AU to 255.50 ± 24.18 AU). Significant Time × Group interactions were observed for DT (p < 0.001) and knee extension torque (p = 0.008). Conclusions: FR appeared beneficial for knee extension performance, whereas CRYO was associated with improved DT performance. Findings are exploratory and need confirmation in larger, controlled studies. Full article

Low temperature constitutes a critical abiotic stress that significantly impairs plant growth and development, particularly for species in cold regions. In Northeast China, the persistently low winter temperatures over an extended period pose significant challenges to the survival of chrysanthemums. This study employed the ground cover plant ‘Yingjie’ as the experimental material and cloned CmMYBS3. The CmMYBS3 protein lacks transcriptional activity and is localized exclusively in the nucleus. Under low-temperature treatment, the activities of SOD, CAT, and POD were significantly lower in chrysanthemums overexpressing CmMYBS3 than in the wild-type line. Additionally, the MDA content in the CmMYBS3 overexpression lines was higher than in the wild-type lines. To elucidate the mechanism by which CmMYBS3 regulates the response to low temperature, we conducted transcriptome sequencing analysis and identified a total of 5425 differentially expressed genes, comprising 2646 upregulated genes and 2779 downregulated genes. The GO analysis reveals that the primary enrichment occurs in the “biological process”, “cellular component”, and “molecular function”. The KEGG enrichment analysis identified significant alterations in several pathways associated with plant growth and development, as well as stress responses. Through yeast single-hybrid analysis, it was demonstrated that CmMYBS3 specifically binds to the promoter region of CmDREB1 and inhibiting the expression of the CmDREB1. This study demonstrates that CmMYBS3 reduces the cold tolerance of ground cover chrysanthemums by suppressing the expression of the CmDREB1 gene, providing an important theoretical basis for the breeding of cold-tolerant ground cover chrysanthemum varieties. Full article

The genus Ilex L., the sole member of the family Aquifoliaceae, is valued for its high ornamental value. However, low winter temperatures restrict the distribution of its evergreen species in colder regions. In this study, detached leaves of seven evergreen Ilex cultivars were subjected to acute low-temperature stress, and key physiological parameters (cell membrane permeability, osmoregulatory substances, and chloroplast pigments) were measured. The results showed that under low-temperature stress, relative electrical conductivity (REC) and malondialdehyde (MDA) content increased with decreasing temperature, while soluble protein (SP), soluble sugar, and free proline (Pro) contents first increased and then decreased. A positive association was observed between REC and MDA, as well as between REC and SP, while REC showed a negative association with Pro. Furthermore, random forest analysis indicated that MDA, proline, and chlorophyll a together accounted for 72.6% of the variance in REC. These findings demonstrate the physiological responses of detached leaves of evergreen Ilex species to acute low-temperature stress and offer an initial assessment of their cold tolerance. Full article

Cold stress is a critical abiotic factor that severely limits plant growth and agricultural productivity in subtropical regions. Poncirus trifoliata exhibits exceptional cold hardiness and is widely used as a rootstock in Citrus. However, the key genes and mechanisms conferring this resilience remain largely unexplored. Here, we characterized PtCOR8, a cold-induced gene isolated from P. trifoliata. Phylogenetic and subcellular localization analyses confirmed that PtCOR8 encodes a plasma membrane-localized protein belonging to the WCOR413 family. Functional validation revealed that heterologous overexpression of PtCOR8 in tomato significantly enhanced cold tolerance, concomitant with reduced malondialdehyde (MDA) content, elevated peroxidase (POD) activity, and upregulation of cold-responsive genes (e.g., CIN8). Notably, expression profiling of COR8 in 16 citrus accessions under natural overwintering conditions indicated a strong positive correlation between its expression level and cold tolerance of different genotypes. Transgenic tomato plants with PtCOR8 driven by its native promoter also presented enhanced cold tolerance, confirming that the native promoter is sufficient to drive functional expression under cold stress in the tomato system. Through promoter deletion and β-glucuronidase (GUS) staining experiments, the ATCT motif was further identified as a cis-acting element capable of mediating cold-induced promoter activity. Our findings uncover a dual-layered mechanism in which the PtCOR8 protein alleviates membrane lipid peroxidation and oxidative damage, while its transcription level is precisely modulated by a novel promoter regulatory mechanism, thereby improving freezing tolerance. This study provides important genetic insights and a valuable gene resource for cold-resistant citrus breeding. Full article

Chickpea (Cicer arietinum L.) is a major annual legume crop with a balanced nutritional profile and a broad spectrum of bioactive constituents; these characteristics have made it a useful ingredient in health-oriented food applications. Chickpea supplies protein that is readily absorbed and digested, along with isoflavones and other bioactive plant compounds that act on physiological pathways associated with chronic disease prevention. Nonetheless, the combined pressures of drought, heat, cold, and salinity persistently limit its yield potential and cultivation stability. This review integrates the most recent progress in chickpea research, with emphasis on its intrinsic value derived from macronutrients, micronutrients, and bioactive metabolites. It further synthesizes the physiological determinants and metabolic reprogramming mechanisms underlying abiotic stress tolerance, outlines precision breeding strategies for developing resilient and high-quality ideotypes, and examines pathways for the high-value utilization of chickpea-derived processing by-products. Future efforts should focus on developing stress-resilient cultivars and expanding chickpea’s application in functional food innovation. Full article

Turpan Black (TBL) and Altay (ALT) sheep are indigenous breeds adapted to extreme heat and severe cold in their respective native environments. However, the mechanisms underlying their divergent meat quality remain unclear. Using longissimus dorsi muscle from 15 TBL and 15 ALT sheep, we integrated phenotypic evaluation with non-targeted metabolomics and proteomics to elucidate the impact of environmental adaptation on ovine meat quality. Compared to the cold-adapted ALT sheep, the heat-tolerant TBL sheep exhibited lower post-mortem pH, reduced cooking loss, smaller muscle fiber cross-sectional area, and elevated selenium and magnesium levels. Multi-omics identified 99 differentially expressed proteins and 364 differentially expressed metabolites. Core divergence was enriched in lipid and amino acid metabolism and stress response networks, particularly the Apelin signaling, glycerophospholipid metabolism, and ferroptosis pathways. Lipid remodeling driven by glycerophospholipid metabolism emerged as a critical bridge linking adaptation to meat quality. Notably, glycero-3-phosphocholine, regulated by GPCPD1 and related enzymes, maintained cell membrane homeostasis and osmotic pressure, thereby enhancing water-holding capacity and tenderness. These findings reveal the multi-omics basis of climate-driven divergence in ovine meat quality, offering theoretical support for breeding stress-resilient, high-quality indigenous sheep breeds in extreme environments. Full article

Cold stress is a major environmental constraint limiting the growth, physiological performance, and productivity of African marigold (Tagetes erecta L.) under open-field conditions. This study evaluated the comparative effectiveness of salicylic acid (SA), silicon (Si), and methyl jasmonate (MeJA) in alleviating cold-induced damage and enhancing stress tolerance. Field experiments were conducted under naturally occurring cold stress using foliar applications of SA (0, 0.1, 0.5, and 1 mM), Si (0, 1, 5, and 10 mM), and MeJA (0, 10, and 50 µM) in a complete randomized block design with three replications. Moderate concentrations of all three regulators significantly (p < 0.05) improved plant growth and physiological stability relative to untreated controls. Salicylic acid at 0.5 mM produced the most consistent protective response, increasing biomass accumulation, chlorophyll content, and relative water content while reducing membrane damage, as indicated by a 42.3% decrease in leaf electrolyte leakage at 2 °C. Silicon at 10 mM enhanced membrane integrity, plant water status, and vegetative growth under low-temperature conditions, while methyl jasmonate at 10 µM mitigated cold-induced membrane damage and improved physiological tolerance, whereas higher concentrations (50 µM) were less effective. At their optimal doses, SA, Si, and MeJA increased plant dry mass by 39.7%, 30.1%, and 38.5%, respectively. Correlation analysis confirmed these results, revealing strong positive relationships among growth, chlorophyll, and relative water content. Conversely, electrolyte leakage was negatively correlated with biomass and water status, identifying membrane stability as a key determinant of cold tolerance. Overall, 0.5 mM SA, 5–10 mM Si, and 10 μM MeJA improved growth and key physiological responses in African marigold under cold stress under field conditions. Future studies should integrate mechanistic and economic analyses to refine growth-regulator-based cold-stress management strategies. Full article

Rapid climate shifts in high-latitude regions profoundly impact the geographical distribution boundaries and molecular adaptive strategies of cold-tolerant plants. Lonicera caerulea, known for its excellent cold tolerance, provides an ideal model for exploring the molecular mechanisms of climate adaptation and trait formation. To elucidate the ecological and molecular mechanisms of climate adaptation in L. caerulea, we integrated species distribution modeling with multi-tissue transcriptome profiling. Distribution modeling identified temperature and precipitation as primary constraints on its current range, with projections suggesting a significant poleward expansion under future warming scenarios. At the molecular level, we identified 19 LcSWEET genes exhibiting functional differentiation. Rather than listing specific candidates, our findings highlight that certain LcSWEET members are transcriptionally activated during fruit maturation, while others are significantly upregulated in response to cold stress, underscoring their dual roles in plant reproduction and ecological adaptation. This study revealed that the LcSWEET gene family exhibits functional diversification in tissue-specific expression and low-temperature stress response. It provides molecular candidates that may inform future studies on plant adaptive response under climate change and lays a theoretical foundation for germplasm conservation and high-quality breeding of L. caerulea. Full article

Cold stress poses a significant challenge to aquatic organisms, affecting their survival, growth, and metabolic processes. This review explores the molecular mechanisms by which fish, crustaceans, and mollusks respond to cold stress, highlighting the shared and species-specific pathways that facilitate adaptation. Common responses to cold stress include modulation of energy metabolism, regulation of oxidative stress, immune responses, and maintenance of proteostasis. In particular, the activation of the adenosine 5′-monophosphate-activated protein kinase (AMPK) and mechanistic target of rapamycin (mTOR) pathways plays a critical role in regulating energy balance and autophagy in response to low temperatures. Furthermore, we examine the specific adaptive mechanisms employed by different groups of aquatic organisms. Fish utilize pathways such as peroxisome proliferator-activated receptor alpha/peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PPAR/PGC-1α) and fatty acid oxidation to optimize energy utilization and improve cold tolerance. Crustaceans rely on crustacean hyperglycemic hormone (CHH) signaling and AMPK pathway activation, while mollusks employ metabolic suppression and glycogen storage to survive cold exposure. Moreover, the regulation of autophagy and apoptosis, mediated by p53 and cyclin-dependent kinase 1 (Cdk1), ensures the survival of healthy cells under prolonged cold stress, with autophagy maintaining energy homeostasis and apoptosis eliminating damaged cells. This review also discusses the role of molecular chaperones like heat shock protein 70 (HSP70) and the ubiquitin-proteasome system (UPS) in protein homeostasis, highlighting their importance to protect cells under cold stress. The combined action of these molecular pathways allows aquatic organisms to cope with and adapt to cold environments, ensuring cellular integrity and enhancing survival. Future research should focus on integrating molecular, physiological, and ecological approaches to better understand cold tolerance mechanisms and improve aquaculture practices under climate change scenarios. Full article

Freeze-drying is the most commonly used method for preserving probiotics. The freeze tolerance of probiotics has a significant impact on both their survival rate and the expression of their functional properties. To enhance the freeze tolerance of probiotics, this study established an adaptive evolution protocol combining cold stress with repeated freeze–thaw cycles to screen for freeze–thaw-tolerant evolved strains of Lacticaseibacillus rhamnosus MP108. The safety, metabolic, and functional characteristics of these strains were then evaluated. The results showed that the combination of the 8 h cold stress treatment at 4 °C and nine cycles of freezing and thawing at −20 °C effectively enhanced the strain’s freeze tolerance, and the evolved strain L134 was successfully screened through adaptive evolution. Its freeze-dried survival rate and storage survival rate after 6 months of storage were both significantly higher than those of the parental strain (p < 0.05). Furthermore, it exhibited good passage stability. At the same time, the safety and acid-producing characteristics of L134 did not show significant changes compared to the parental strain. Furthermore, its tolerance to simulated gastric fluid, antibacterial activity, and antioxidant capacity were significantly enhanced (p < 0.05). In particular, compared to MP108, L134 exhibited significantly increased hydroxyl radical scavenging capacity as well as higher activities of the antioxidant enzymes SOD and CAT (p < 0.05); the improvement in its freeze tolerance may be related to this enhanced antioxidant capacity. Full article

Background: Cold stress is a major abiotic factor limiting rice growth and yield. Elucidating the molecular mechanisms underlying cold tolerance is therefore of great significance for variety improvement. This study focused on the cold-tolerant variety QJ10 and the cold-sensitive variety DHX2, systematically comparing their physiological and transcriptomic differences under cold stress and identifying genes and modules associated with the cold stress response. Methods: After 0, 3, 5, and 7 days of treatment at 4 °C, we measured leaf MDA and Pro contents, as well as SOD and POD activities. We performed multi-time-point transcriptome sequencing using RNA-seq, and conducted data mining and validation through differential expression analysis, Mfuzz trend clustering, WGCNA co-expression network analysis, GENIE3 regulatory network prediction, and qRT-PCR. Results: Compared with DHX2, QJ10 exhibited lower MDA levels and higher levels of Pro, SOD, and POD under cold stress. Transcriptome analysis identified a total of 13,599 differentially expressed genes. Trend clustering revealed that QJ10 primarily maintained genes associated with growth, development, and basal metabolism, whereas DHX2 tended to activate defense responses. WGCNA identified the MEturquoise module, which showed significant positive correlations with both cold treatment duration and the activities of SOD and POD. Genes in this module were significantly enriched in pathways such as carbon metabolism, photosynthesis, and ion transport. Twelve key transcription factors were identified, nine of which were highly expressed at the late stage of cold stress in QJ10. GENIE3 further predicted seven key regulatory factors centered on OsNAC2, OsLBD, and OsARF19; the expression patterns of these factors were validated by qRT-PCR and were consistent with the transcriptomic results. Conclusions: This study revealed that the cold tolerance of QJ10 is associated with enhanced antioxidant capacity, upregulation of genes related to carbon metabolism, and the induced expression of specific transcription factors. The key transcription factors identified here provide candidate genes for studying the molecular mechanisms of cold tolerance in rice. However, their regulatory functions require further experimental validation. Full article

Banana fruits are susceptible to chilling injury (CI) under field conditions, which significantly impairs fruit quality. Cold tolerance varies among genotypes; however, only a limited number of cultivars have been identified as tolerant and are commercially cultivated. This study aimed to investigate the physiological responses and quality attributes of banana cultivars exposed to natural cold fronts during development, compared with fruits developed under summer conditions. Furthermore, it evaluated whether the B genome confers greater cold tolerance, driven by a more efficient antioxidant mechanism, thereby supporting its recommendation for cultivation in regions prone to low temperatures. Bunches were harvested in winter following five natural cold fronts, during which air temperatures fell below 12 °C (137 h). The experimental design followed a completely randomized design in a factorial arrangement. Consecutive cold fronts intensified CI symptoms up to the fourth exposure event. CI severity was highest in ‘Grande Naine’ (AAA), which exhibited lower L*, a*, and b* values at the ripe stage compared to ‘BRS Princesa’ (AAAB) and ‘Prata Catarina’ (AAB), along with greater deviations relative to summer-harvested fruits. Malondialdehyde (MDA), total phenolic content, and antioxidant enzyme activities (SOD, CAT, APX, and POD) in the peel of unripe fruits were significantly higher during winter, particularly in ‘BRS Princesa’ and ‘Prata Catarina’, compared to ‘Grande Naine’. Proline accumulation followed a similar pattern, with the highest levels observed in ‘BRS Princesa’, followed by ‘Prata Catarina’ and ‘Grande Naine’. The findings indicate that ‘BRS Princesa’ exhibits greater tolerance to cold stress and highlights of the contribution of the B genome. Phenolic content was identified as a consistent marker of seasonal variation across cultivars. Full article

Drought stress is a major limiting factor for alfalfa (Medicago sativa L.) production in arid and semi-arid regions. Cold plasma treatment has emerged as a promising physical technology for improving seed germination and stress tolerance, but its underlying mechanisms remain poorly understood. In this study, alfalfa seeds were treated with cold plasma (plasma discharge voltage: 0, 5, 10, 15 kV) for 5 min and exposed to PEG 6000 stress at 0, 5, 10, and 15%. Results showed that cold plasma treatment significantly alleviated the inhibitory effects of drought stress on seed germination, with the Plasma-15 kV treatment exhibiting the highest germination potential and germination rate compared to the control (p < 0.05). Plasma treatment enhanced the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), while reducing malondialdehyde (MDA) content (p < 0.05), indicating mitigated oxidative damage under drought conditions. Transcriptomic analysis revealed that cold plasma regulated the expression of genes involved in the MAPK signaling pathway and other drought-responsive pathways, leading to metabolic reallocation (Q < 0.05) and enhanced drought tolerance. In conclusion, 5 min of Plasma-15 kV treatment effectively enhances drought tolerance via physiological and transcriptional regulation, providing an eco-friendly strategy for alfalfa cultivation in dry regions. Full article

One potential strategy to mitigate the detrimental effects of heat stress on corals is upwelling, which brings deep, cold, nutrient-rich water to the reef surface, creating transient cooling. However, cold temperatures can also stress corals, and it is, therefore, important to understand the mechanisms of both cold and heat stress responses in corals. Similar to how mammals activate thermogenic and adaptive metabolic pathways, corals may also regulate energy and redox metabolism under fluctuating environmental conditions. Guanosine monophosphate reductase (GMPR), a conserved enzyme in purine metabolism, plays a critical role in maintaining intracellular adenine and guanine nucleotide balance. To study this enzyme in corals, we expressed Pocillopora damicornis (PD) GMPR heterologously in Escherichia coli and purified the recombinant protein using nickel–NTA affinity chromatography. SDS-PAGE analysis showed a single band corresponding to the expected molecular weight, indicating high purity. Sequence alignment revealed ~70% identity with mammalian GMPR2 orthologs, suggesting evolutionary conservation of function. Structural modeling and phylogenetic analysis positioned PD GMPR between the GMPR1 and GMPR2 clades, suggesting it may represent an ancestral or functionally intermediate variant. Kinetic analysis determined Km values of 33.76 ± 6.44 μM for GMP and 17.71 ± 0.99 μM for NADPH under fixed substrate concentrations. This study provides the first biochemical characterization of GMPR, which may open the door to uncovering mechanisms of cold tolerance in corals and inform strategies to enhance coral resilience in the face of climate change. Full article

Tea plants (Camellia sinensis) suffer growth limitations under cold stress. Jasmonic acid (JA) and long non-coding RNAs (lncRNAs) are involved in stress responses, yet how lncRNAs regulate JA-mediated cold tolerance remains unclear. Here, we identified an lncRNA, lnc015013, whose silencing compromised cold tolerance in tea plants, a phenotype rescued by exogenous methyl jasmonate (MeJA). Silencing lnc015013 down-regulated CsMYB30 and CsJAZ4/6, while its overexpression had opposite effects. Heterologous expression in Arabidopsis thaliana showed that CsMYB30 enhanced cold resistance, whereas CsJAZ4/6 suppressed it. Mechanistically, CsMYB30 repressed CsJAZ4/6 promoter activity and physically interacted with CsJAZ4/6, with MeJA attenuating this interaction. These findings reveal that the lnc015013-CsMYB30-CsJAZ4/6 module regulates JA biosynthesis within the JA signaling pathway, providing a novel mechanism for cold adaptation in tea plants and a theoretical basis for molecular breeding. Full article