RESUMEN

Water temperature is a crucial environmental factor that significantly affects the physiological and biochemical processes of fish. Due to the occurrence of cold events in aquaculture, it is imperative to investigate how fish respond to cold stress. This study aims to uncover the mechanisms responds to acute cold stress by conducting a comprehensive analysis of the histomorphology, glycolipid metabolic and antioxidant enzymes, fatty acid composition and transcriptome at three temperatures (16 °C, 10 °C and 4 °C) in Phoxinus lagowskii. Our results showed that cold stress not damaged muscle microstructure but caused autophagy (at 10 °C). In addition, serum glucose (Glu) and triglycerides (TG) increased during cold stress. The activities of reactive oxygen species (ROS), superoxide dismutase (SOD), catalase (CAT), fructose phosphokinase (PFK), hexokinase (HK), pyruvate kinase (PK), and malondialdehyde (MDA) content in muscle were measured and analyzed. During cold stress, superoxide dismutase and catalase activities increased, reactive oxygen species content decreased. No significant difference in Glutathione peroxidase (GPx) activity, malondialdehyde and total cholesterol (T-CHO) contents among groups. Phosphokinase and pyruvate kinase activities decreased, and HK activity increased during cold stress. Our study resulted in the identification of a total of 25,400 genes, with 2524 genes showing differential expression across different temperature treatments. Furthermore, KEGG pathway indicated that some pathways upregulated during light cold stress (at 10 °C, including autophagy, and AMP-activated protein kinase (AMPK) signaling pathway. Additionally, circadian rhythm is among the most enriched pathways in genes up-regulated during severe cold stress (at 4 °C). Our findings offer valuable insights into how cold-water fish respond to cold stress.

Asunto(s)

Antioxidantes , Respuesta al Choque por Frío , Cyprinidae , Ácidos Grasos , Glucolípidos , Animales , Cyprinidae/genética , Cyprinidae/fisiología , Cyprinidae/metabolismo , Ácidos Grasos/metabolismo , Antioxidantes/metabolismo , Glucolípidos/metabolismo , Transcriptoma , Perfilación de la Expresión Génica

RESUMEN

Cold tolerance of adult medflies has been extensively studied but the effect of subfreezing temperatures on the immature stages remains poorly investigated, especially as far as different populations are regarded. In this study, we estimated the acute cold stress response of three geographically divergent Mediterranean fruit fly populations originating from Greece (Crete, Volos) and Croatia (Dubrovnik) by exposing immature stages (eggs, larvae, pupae) to subfreezing temperatures. We first determined the LT50 for each immature stage following one hour of exposure to different temperatures. Then eggs, larvae and pupae of the different populations were exposed to their respective LT50 for one hour (LT50 = -11 °C, LT50 = -4.4 °C, LT50 = -5 °C for eggs, larvae and pupae, respectively). Our results demonstrate that populations responded differently depending on their developmental stage. The population of Dubrovnik was the most cold-susceptible at the egg stage, whereas in that of Crete it was at the larval and pupal stage. The population of Volos was the most cold-tolerant at all developmental stages. The egg stage was the most cold-tolerant, followed by pupae and finally the 3rd instar wandering larvae. This study contributes towards understanding the cold stress response of this serious pest and provides data for important parameters that determine its successful establishment to unfavorable environments with an emphasis on range expansion to the northern, more temperate regions of Europe.

RESUMEN

Objectives: Aim of the current study was to evaluate the stress-protective effect of oligopeptides-homologues of the adrenocorticotropic hormone (ACTH) fragment 15-18 on morphogenetic signs of stress reaction of the adrenal glands under acute cold exposure (CE) in rats. Materials and Methods: The acute cold stress was reproduced by placing random-bred male rats in a freezer at a temperature of -18°C for 2 hours. The peptides-homologous of ACTH15-18 acetyl-(D-Lys)-Lys-Arg-Arg-amide (KK-1) and acetyl-(D-Lys)-Lys-(D-Arg)-Arg-amide (KK-5) and the reference medicine (Sema) were administered intranasally in a dose of 20 mg/kg 30 minutes before and after CE. Rectal temperature was measured before and 10 min after CE. Zona glomeruloza, zona fasciculata, zona reticularis, and the area of cells and nuclei of adrenocorticocytes of the zona fasciculata were measured. Results: KK-1 significantly prevented structural changes in the adrenal cortex and medulla and stabilized the secretory activity of glucocorticoid-producing cells. However, the congestion of the capillaries of the zona fasciculata and zona reticularis remained in some locations. Zona fasciculata cells had a marked tendency to decrease, and the area of nuclei significantly decreased (p<0.05) recovering the width to control animals' markers. KK-5 had a more marked recovery of the adrenal glands (a greater saturation of cytoplasm of adrenocorticocytes of zona glomerulosa and zona fasciculata). The number of chromaffin cells at rest was increased in the adrenal medulla. KK-5 statistically significantly normalized both the area of cells (p<0.05) and the area of nuclei (p<0.05) of the zona fasciculata, unlike KK-1, which reliably restored only the marker of the nuclei area. Some morphometric parameters of acute stress hypertrophy remained in the adrenal glands of rats receiving Sema. Conclusion: KK-1 and KK-5 prevented the manifestation of acute stress reactions in the adrenal cortex of rats. KK-5 had a more marked stress-protective effect compared with the peptide KK-1. Both study substances exceeded the reference medicine Sema. KK-5 is a promising stres-sprotector and frigoprotector.

RESUMEN

Cold environment is an inevitable stress source for humans and livestock in cold areas, which easily induce a cold stress response and then cause a series of abnormal changes in energy metabolism, neuroendocrine system, behavior and emotion. Homeostasis is maintained by the unified regulation of the autonomic nervous system, endocrine system, metabolism and behavior under cold exposure. Behavior is an indispensable part of the functional regulation of the body to respond to environmental changes. At present, the behavioral changes caused by cold exposure are unclear or even chaotic due to the difficulty of defining cold stress. Therefore, this study aims to systematically observe the changes in spontaneous movement, exploratory behavior and anxiety of mice under different intensity cold exposure and summarize the characteristics and behavior traits combined with relevant blood physiological indexes under corresponding conditions. Mice models of cold stress with different intensities were established (cold exposure gradients were 22 °C, 16 °C, 10 °C and 4 °C, and time gradients of each temperature were 2 h, 4 h, 6 h, 8 h, 10 h and 12 h). After the corresponding cold exposure treatment, mice immediately carried out the open field test(OFT) and elevated plus maze test (PMT) to evaluate their spontaneous movement, exploratory behavior and anxiety. Subsequently, blood samples were collected and used for the determination of corticosterone (Cort), corticotropin-releasing hormone (CRH), epinephrine (E), norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT) by enzyme-linked immunosorbent assay (ELISA). Spontaneous movement of mice increased under 22 °C cold exposure, but their exploration behavior did not significantly change, and their anxiety improved at the initial stage. The spontaneous movement and anxiety of mice increased in the initial stage and decreased in the later stage under cold exposure at 16, 10 and 4 °C and the exploratory behavior was inhibited. The hypothalamic-pituitary-adrenal (HPA) axis and locus coeruleus-noradrenergic (LC/NE) system were activated by cold stress and fluctuated with different intensities of cold exposure. Meanwhile, serum DA increased, and 5-HT was the opposite under different intensities of cold exposure. In conclusion, mild acute cold exposure promoted the spontaneous movement, increased exploratory behavior and improved anxiety. As the intensity of cold exposure increases, cold exposure had a negative effect on spontaneous movement, exploratory behavior and emotion. The physiological basis of these behavioral and emotional changes in mice under different intensity cold stimulation is the fluctuation of Cort, CRH, E, NE, DA and 5-HT.

RESUMEN

The Chinese soft-shelled turtle (Pelodiscus sinesis) is a widely cultured commercial species in East and Southeast Asian countries. The turtles frequently suffer from acute cold stress during farming in China. Stress-induced factor such as Interleukin-6 (IL6) is a multifunctional molecule that plays important roles in innate and adaptive immune response. In the present study, we found that the turtle possessed two IL6 transcripts, where one IL6 transcript contained a signal peptide sequence (psIL6), while the other IL6 transcript (psIL6ns) possessed no such signal peptide gene. To test any differential expression of the two isoforms during temperature and microbial stress, turtles were adapted to optimal environmental water temperature (25 °C), stressed by acute cooling for 24 h, followed with the challenge of Aeromonas hydrophila (1.8 × 108 CFU) or Staphylococcus aureus (5.8 × 108 CFU). Gene characterization revealed that psIL6ns, a splicer without codons encoding a signal peptide and identical to the one predicted from genomic sequence, and psIL6, a splicer with codons encoding a signal peptide, were both present. Inducible expression was documented in primary spleen cells stimulated with ConA and poly I: C. The splenic and intestinal expression of psIL6ns and psIL6 was increased in response to temperature stress and bacterial infection.

RESUMEN

The noble scallop Chlamys nobilis is an important edible marine bivalve that is widely cultivated in the sea of southern China. Unfortunately, the mass mortality of noble scallops frequently occurs during the winter months. The present study investigated the effects of acute cold stress (8 °C) to the physiological responses of polymorphic noble scallops, by assessing the HSP70 gene expression, total carotenoid content (TCC), total antioxidant capacity (TAC), malondialdehyde (MDA) content, catalase (CAT) activity and superoxide dismutase (SOD) enzymatic activity in different tissues of golden and brown scallops. The results of the present study revealed that MDA, TCC and CAT increased drastically in most tissues in the early stage of acute cold stress (0-3 h), but TCC, SOD and CAT generally showed a downward trend. Within 3-6 h of acute cold stress, MDA content decreased in most tissues and the SOD content increased significantly in most tissues, while TCC and CAT remained at peak. After 6 h of acute cold stress, MDA content continued to increase in most tissues, while TCC, CAT, SOD and TAC decreased or remained at a lower level. For HSP70 expression, up-regulation of the HSP70 gene was observed only in mantle of brown scallops and hemolymph of golden scallops at 3 h and 24 h, respectively. The findings of the present study can better understand the physiological response of noble scallops to acute cold stress.

Asunto(s)

Carotenoides/metabolismo , Frío/efectos adversos , Inmunidad Innata/fisiología , Estrés Oxidativo/fisiología , Pectinidae/fisiología , Animales , Antioxidantes/metabolismo , Proteínas de Peces/metabolismo , Expresión Génica , Inmunidad Innata/genética , Pectinidae/inmunología

RESUMEN

In this present study, Oreochromis mossambicus tilapia were transferred to cold water at 12°C for various time intervals (1, 4, 8, 24, and 48 hr) and its innate immune response was analyzed by studying cellular and humoral parameters. In vivo, alternative complement pathway activity in blood plasma was rapidly increased at 1 hr of cold water (12°C) exposure. Lysozyme activity and cortisol levels of plasma were increased at 4 and 1 hr, respectively. Surprisingly, only plasma cortisol levels remained unchanged through 24 hr of cold water transfer. Phagocytic ability, phagocytic capacity, and respiratory burst (RB) activity of head kidney (HK) leukocytes and splenocytes showed no any significant changes. In peripheral blood leukocytes, phagocytic capacity, and RB activity were increased at 24 hr of cold water exposure. The expressions of genes involved innate immunity in splenocytes and HK leukocytes of tilapia cold water exposure were analyzed, messenger RNA (mRNA) expressions of HSP70, HSP90, and immunoglobulin M failed to change upon exposure to cold stress. Major histocompatibility complex-I and II mRNAs were significantly increased in tilapia splenocytes at 1 hr of cold water transferred. Whereas myxovirus (Mx) expression was increased in splenocytes and HK leukocytes of tilapia after 1 hr of cold water exposed. Our result reveals that the exposure of tilapia to acute cold stress condition significantly enhances plasma acid phosphatase activity and both phagocytic capacity and RB activity. Furthermore, cold stress significantly stimulates Mx gene expression in splenocytes and HK leukocytes.

RESUMEN

Metabolic profiling technology, a massive information provider, has promoted the understanding of the metabolism of multicomponent medicines and its interactions with endogenous metabolites, which was previously a challenge in clarification. In this study, an untargeted GC/MS-based approach was employed to investigate the urinary metabolite profile in rats with oral administration of ginsenosides and the control group. Significant changes of urinary metabolites contents were observed in the total ginsenosides group, revealing the impact of ginsenosides as indicated by the up- or down-regulation of several pathways involving neurotransmitter-related metabolites, tricarboxylic acid (TCA) cycle, fatty acids ß-oxidation, and intestinal microflora metabolites. Meanwhile, a targeted UPLC-QQQ/MS-based metabonomic approach was developed to investigate the changes of urinary ginsenoside metabolites during the process of acute cold stress. Metabolic analysis indicated that upstream ginsenosides (rg1, re, and rf) increased significantly, whereas downstream ginsenosides (ck, ppd, and ppt) decreased correspondingly after cold exposure. Finally, the relationships between ginsenosides and significantly changed metabolites were investigated by correlation analysis.

Asunto(s)

Respuesta al Choque por Frío , Ginsenósidos/metabolismo , Metabolómica , Animales , Cromatografía de Gases y Espectrometría de Masas , Ginsenósidos/administración & dosificación , Ginsenósidos/farmacología , Redes y Vías Metabólicas/efectos de los fármacos , Metabolómica/métodos , Ratas , Orina/química

RESUMEN

Chinese soft-shelled turtle, Pelodiscus sinensis, is widely cultured in East and Southeast Asian countries. It frequently encounters the stress of abrupt temperature changes, which leads to mass death in most cases. However, the mechanism underlying the stress-elicited death remains unknown. We have suspected that the stress impaired the immune function of Chinese soft-shelled turtle, which could result in the mass death, as we noticed that there was a clinical syndrome of infection in dead turtles. To test our hypothesis, we first performed bioinformatic annotation of several pro-inflammatory molecules (IL-1ß, TNFα, IL-6, IL-12ß) of Chinese soft-shelled turtle. Then, we treated the turtles in six groups, injected with Aeromonas hydrophila before acute cold stress (25 °C) and controls, after acute cold stress (15 °C) and controls as well as after the temperature was restored to 25 °C and controls, respectively. Subsequently, real-time PCR for several pro-inflammatory cytokines (IL-1ß, TNFα, IL-6, IL-12ß, IL-8 and IFNγ) was performed to assess the turtle immune function in spleen and intestine, 24 hours after the injection. We found that the mRNA expression levels of the immune molecules were all enhanced after acute cold stress. This change disappeared when the temperature was restored back to 25 °C. Our results suggest that abrupt temperature drop did not suppress the immune function of Chinese soft-shelled turtle in response to germ challenge after abrupt temperature drop. In contrast, it may even increase the expression of various cytokines at least, within a short time after acute cold stress.

Asunto(s)

Aeromonas hydrophila/inmunología , Frío , Citocinas/inmunología , Transcripción Genética/inmunología , Tortugas/inmunología , Aeromonas hydrophila/fisiología , Secuencia de Aminoácidos , Animales , Citocinas/clasificación , Citocinas/genética , Interacciones Huésped-Patógeno/inmunología , Mediadores de Inflamación/inmunología , Mediadores de Inflamación/metabolismo , Interleucina-12/clasificación , Interleucina-12/genética , Interleucina-12/inmunología , Interleucina-1beta/clasificación , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Interleucina-6/clasificación , Interleucina-6/genética , Interleucina-6/inmunología , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Estrés Fisiológico/genética , Estrés Fisiológico/inmunología , Factor de Necrosis Tumoral alfa/clasificación , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología , Tortugas/genética , Tortugas/microbiología

RESUMEN

This study investigated whether there are any gender differences in body-heating strategies during cold stress and whether the immune and neuroendocrine responses to physiological stress differ between men and women. Thirty-two participants (18 men and 14 women) were exposed to acute cold stress by immersion to the manubrium level in 14 °C water. The cold stress continued until rectal temperature (TRE) reached 35.5 °C or for a maximum of 170 min. The responses to cold stress of various indicators of body temperature, insulation, metabolism, shivering, stress, and endocrine and immune function were compared between men and women. During cold stress, TRE and muscle and mean skin temperatures decreased in all subjects (P<0.001). These variables and the TRE cooling rate did not differ between men and women. The insulative response was greater in women (P<0.05), whereas metabolic heat production and shivering were greater (P<0.05) in men. Indicators of cold strain did not differ between men and women, but men exhibited larger changes in the indicators of neuroendocrine (epinephrine level) and in immune (tumor necrosis factor-α level) responses (both P<0.05). The results of the present study indicated that men exhibited a greater metabolic response and shivering thermogenesis during acute cold stress, whereas women exhibited a greater insulative response. Despite the similar experience of cold strain in men and women, the neuroendocrine and immune responses were larger in men. Contrary to our expectations, the cooling rate was similar in men and women.

Asunto(s)

Regulación de la Temperatura Corporal/fisiología , Frío , Respuesta al Choque por Frío , Sistemas Neurosecretores/fisiología , Adolescente , Adulto , Temperatura Corporal , Epinefrina/sangre , Femenino , Frecuencia Cardíaca , Humanos , Hidrocortisona/sangre , Inmersión , Masculino , Neopterin/sangre , Norepinefrina/sangre , Factores Sexuales , Tiritona , Factor de Necrosis Tumoral alfa/metabolismo , Adulto Joven

RESUMEN

Frost (Fst) is a candidate gene associated with the response to cold in Drosophila melanogaster because Fst mRNA accumulation increases during recovery from low temperature exposure. We investigated the contribution of Fst expression to chill-coma recovery time, acute cold tolerance and rapid cold hardening (RCH) in adult D. melanogaster by knocking down Fst mRNA expression using GAL4/UAS-mediated RNA interference. In this experiment, four UAS-Fst and one tubulin-GAL4 lines were used. We predicted that if Fst is essential for cold tolerance phenotypes, flies with low Fst mRNA levels should be less cold tolerant than flies with normal levels of cold-induced Fst mRNA. Cold-induced Fst abundance and recovery time from chill-coma were not negatively correlated in male or female flies. Survival of 2 h exposures to sub-zero temperatures in Fst knockdown lines was not lower than that in a control line. Moreover, a low temperature pretreatment increased survival of severe cold exposure in flies regardless of Fst abundance level during recovery from cold stress, suggesting that Fst expression is not essential for RCH. Thus, cold-induced Fst accumulation is not essential for cold tolerance measured as chill-coma recovery time, survival to acute cold stress and RCH response in adult D. melanogaster.

Asunto(s)

Frío , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , ARN Mensajero/biosíntesis , Estrés Fisiológico , Envejecimiento/genética , Animales , Drosophila melanogaster/genética , Femenino , Masculino , Fenotipo , Interferencia de ARN , ARN Mensajero/metabolismo , Estrés Fisiológico/genética