Heat acclimation provides cardiovascular protection in high-temperature environments through multilevel mechanisms; however, the complete molecular basis of its effects remains unclear. In this paper, we systematically review the effects of heat acclimation on blood volume, vascular function, cardiac structure, energy metabolism, and anti-stress regulation, revealing their potential mechanisms in cardiovascular adaptive protection. We also summarizes the multilevel responses induced by heat stress and heat acclimation, including the modulatory effects of heat acclimation on heat shock proteins (HSPs), hypoxia inducible factor 1 (HIF-1), and apoptotic pathways. Additionally, we highlights the comprehensive protective effects of heat acclimation across various stressors (e.g., hypoxia, heat stress). This review provides a significant physiological basis for cardiovascular disease management and sports medicine, emphasizing the potential application of heat acclimation in response to multiple stressors and supporting its role as an effective tool in cardiovascular health management and stress protection interventions.
Humans ; Acclimatization/physiology* ; Hot Temperature ; Heat-Shock Proteins/metabolism* ; Animals ; Heat-Shock Response/physiology* ; Hypoxia-Inducible Factor 1/metabolism* ; Apoptosis/physiology*

The alteration of pulmonary artery pressure is an important physiological indicator to reflect the organism's adaptation to acclimatization or the pathological injury in response to high-altitude hypoxic environment. The effects of hypoxic stress at different altitudes for different time on pulmonary artery pressure are different. There are many factors involved in the changes of pulmonary artery pressure, such as the contraction of pulmonary arterial smooth muscle, hemodynamic changes, abnormal regulation of vascular activity and abnormal changes of cardiopulmonary function. Understanding of the regulatory factors of pulmonary artery pressure in hypoxic environment is crucial in clarifying the relevant mechanisms of hypoxic adaptation, acclimatization, prevention, diagnosis, treatment and prognosis of acute and chronic high-altitude diseases. In recent years, great progress has been made in the study regarding the factors affecting pulmonary artery pressure in response to high-altitude hypoxic stress. In this review, we discuss the regulatory factors and intervention measures of pulmonary arterial hypertension induced by hypoxia from the aspects of hemodynamics of circulatory system, vasoactive state and changes of cardiopulmonary function.
Humans ; Altitude ; Arterial Pressure ; Acclimatization ; Hypoxia ; Muscle, Smooth

Acclimatization ; Acinetobacter ; metabolism ; Cold Temperature ; Transcriptome

BACKGROUND/OBJECTIVES: A high-fat diet (HFD) induces obesity, which is a major risk factor for cardiovascular disease and cancer, while a calorie-restricted diet can extend life span by reducing the risk of these diseases. It is known that health effects of diet are partially conveyed through epigenetic mechanism including DNA methylation. In this study, we investigated the genome-wide hepatic DNA methylation to identify the epigenetic effects of HFD-induced obesity. MATERIALS AND METHODS: Seven-week-old male C57BL/6 mice were fed control diet (CD), calorie-restricted control diet (CRCD), or HFD for 16 weeks (after one week of acclimation to the control diet). Food intake, body weight, and liver weight were measured. Hepatic triacylglycerol and cholesterol levels were determined using enzymatic colorimetric methods. Changes in genome-wide DNA methylation were determined by a DNA methylation microarray method combined with methylated DNA immunoprecipitation. The level of transcription of individual genes was measured by real-time PCR. RESULTS: The DNA methylation statuses of genes in biological networks related to lipid metabolism and hepatic steatosis were influenced by HFD-induced obesity. In HFD group, a proinflammatory Casp1 (Caspase 1) gene had hypomethylated CpG sites at the 1.5-kb upstream region of its transcription start site (TSS), and its mRNA level was higher compared with that in CD group. Additionally, an energy metabolism-associated gene Ndufb9 (NADH dehydrogenase 1 beta subcomplex 9) in HFD group had hypermethylated CpG sites at the 2.6-kb downstream region of its TSS, and its mRNA level was lower compared with that in CRCD group. CONCLUSIONS: HFD alters DNA methylation profiles in genes associated with liver lipid metabolism and hepatic steatosis. The methylation statuses of Casp1 and Ndufb9 were particularly influenced by the HFD. The expression of these genes in HFD differed significantly compared with CD and CRCD, respectively, suggesting that the expressions of Casp1 and Ndufb9 in liver were regulated by their methylation statuses.
Acclimatization ; Animals ; Body Weight ; Cardiovascular Diseases ; Caspase 1 ; Cholesterol ; Diet ; Diet, High-Fat ; DNA Methylation* ; DNA* ; Eating ; Epigenomics ; Humans ; Immunoprecipitation ; Lipid Metabolism ; Liver ; Male ; Methods ; Methylation ; Mice ; Mice, Obese* ; NADH Dehydrogenase ; Obesity ; Oxidoreductases ; Real-Time Polymerase Chain Reaction ; Risk Factors ; RNA, Messenger ; Transcription Initiation Site ; Triglycerides

The purpose of this study is to investigate whether nicotinic acid (NA) and nicotinamide (NAM) reduce the Alzheimer disease (AD)-related gene expression in brain tissues of amyloid beta (Aβ)-injected mice. Male Crj:CD1 (ICR) mice were divided into 6 treatment groups; 1) control, 2) Aβ control, 3) Aβ + NA 20 mg/kg/day (NA20), 4) Aβ + NA40, 5) Aβ + NAM 200 mg/kg/day (NAM200), and 6) Aβ + NAM400. After 1-week acclimation period, the mice orally received NA or NAM once a day for a total of 7 successive days. On day 7, biotinylated Aβ42 was injected into mouse tail vein. At 5 hours after the injection, blood and tissues were collected. Aβ42 injection was confirmed by Western blot analysis of Aβ42 protein in brain tissue. NAM400 pre-treatment significantly reduced the gene expression of amyloid precursor protein and presenilin 1 in brain tissues. And, NAM200 and NAM400 pre-treatments significantly increased sirtuin 1 expression in brain tissues, which is accompanied by the decreased brain expression of nuclear factor kappa B by 2 doses of NAM. Increased expression of AD-related genes was attenuated by the NAM treatment, which suggests that NAM supplementation may be a potential preventive strategy against AD-related deleterious changes.
Acclimatization ; Aging ; Alzheimer Disease ; Amyloid* ; Animals ; Blotting, Western ; Brain* ; Gene Expression ; Humans ; Male ; Mice* ; NF-kappa B ; Niacin ; Niacinamide* ; Presenilin-1* ; Presenilins* ; Sirtuin 1 ; Tail ; Veins*

BACKGROUND: The objectives of the present study are to: (i) evaluate the effect of environmental and metabolic heat on heat-related illnesses in outdoor workers; and (ii) evaluate the effect of personal factors, including heat acclimation, on the risk of heat-related illnesses in outdoor workers. METHODS: We identified 47 cases of illnesses from exposure to environmental heat in outdoor workers in Korea from 2010 to 2014, based on review of workers' compensation data. We also obtained the information on location, time, and work environment of each heat-related illness. RESULTS: Our major results are that 29 cases (61.7%) occurred during a heat wave. Forty five cases (95.7%) occurred when the maximum estimated WBGT (WBGTmax) was equal to or greater than the case specific threshold value which was determined by acclimatization and metabolic rate. Twenty two cases (46.8%) were not acclimated to the heat. Thirty-seven cases (78.7%) occurred after tropical night (temperature above 25 °C), during which many people may find it hard to sleep. CONCLUSION: Personal risk factors such as heat acclimation as well as environmental factors and high metabolic rate during work are the major determinants of heat-related illnesses.
Acclimatization ; Extreme Heat* ; Hot Temperature ; Humans ; Infrared Rays ; Korea ; Risk Factors ; Workers' Compensation

OBJECTIVE: To determine bleeding time using Moringa oleifera leaf extract versus saline control in an experimental epistaxis model.
METHODS:
Design: Randomized controlled trial
Setting: Tertiary Government Training Hospital
Participants: Ten adult male New Zealand White rabbits were acclimatized for 1 week in a standard environment. One-centimeter long, full-thickness mucosal wounds in the junction of the nasal floor and anterior part of the septum were treated randomly with topical Moringa oleifera extract or colored isotonic saline control in either right or left nasal cavity, one site at a time. The duration of bleeding - time bleeding started to time bleeding stopped -- was recorded in seconds. Data was subjected to a t-test for paired samples.
RESULTS: The mean bleeding time for wounds treated with Moringa extract was 53 seconds (range 38-70 secs), versus 159 seconds (range 100-218 secs) for controls. The bleeding time in the former was significantly shorter than in the latter (p = .000019, t-stat = 8.139), with a mean difference of 106 seconds between the two groups.
CONCLUSION: Moringa oleifera leaf extract was associated with significantly shorter bleeding time than saline control in this experimental epistaxis model and may be worth investigating further as a hemostatic agent for epistaxis.

Animal ; Male ; Rabbits ; Moringa Oleifera ; Moringa ; Epistaxis ; Bleeding Time ; Nasal Cavity ; Hemostatics ; Nose ; Acclimatization ; Environment ; Erythromycin

PURPOSE: This study was done to explore adaptation experience of living kidney donors after donation. Specific aims were to identify challenges donors face in the process of adaptation following surgery and how they interact with recipients and other people. METHODS: Grounded theory methodology was utilized. Participants were 13 living kidney donors at six months or more after donation. Data were collected by in-depth interviews with individual participants. Data were analyzed using constants comparative method with theoretical saturation. RESULTS: A core category emerged as 'keeping the fences of my family in spite of vulnerability'. The adaptation process after donation was manifested in four phases: exploration, balance, maintenance, and acclimatization. Phenomenon was perception of vulnerability. Strategies to manage the vulnerability were assessing changes of body awareness, tailoring regimen to one's own body condition, coping with health problems, keeping restoration of health, and ruminating on the meaning of one's kidney donation. Consequences were reestablishing family well-being, realizing the values of one's kidney donation, and living with uncertainty. CONCLUSION: Findings of the study indicate that there is a need for health professionals to understand the vulnerability of living kidney donors and help their family system maintain a healthy and productive life. The results of this study can be used to develop phase-specific, patient-centered, and tailored interventions for living kidney donors.
Acclimatization ; Health Occupations ; Humans ; Kidney* ; Living Donors ; Organ Transplantation ; Qualitative Research ; Tissue Donors* ; Uncertainty

We designed two types of pre-adaption plans for this study. One was a pre-adaption training with progressive intermittent hypoxia, with a constant lower pressure oxygen tank used in the plain before arriving at the plateau (PG). The other was by progressively increasing the time of exposure to hypoxia with oxygen supplied in stages after radical plateau (RG). By testing the blood oxygen saturation (SpO2), heart rate (HR), and quality of sleep after arriving at the 3800 m high plateau, results showed that the pre-acclimatization and radical groups performed better than the control group (CG). Both strategies were equivalent in terms of effects and principles in providing more flexible choices for acclimatization.
Acclimatization ; Adaptation, Physiological ; Environment ; Heart Rate ; Humans ; Hypoxia ; metabolism ; physiopathology ; Oxygen ; metabolism

The quantitative sudomotor axon reflex testing (QSART) is a classic test of routine postganglionic sudomotor function. We investigated sudomotor function by QSART after summer (July 2012) and winter (January 2013) seasonal acclimation (SA) in the Republic of Korea. QSART with acetylcholine (ACh) iontophoresis were performed to determine directly activated (DIR) and axon reflex-mediated (AXR1, 2) sweating rate. Onset time of axon reflex, activated sweat gland density (ASGD), activated sweat gland output (ASGO), tympanic and skin temperatures (T(ty), T(sk)), basal metabolic rate (BMR), and evaporative loss volume changes were measured. Tympanic and mean body temperature (T(b); calculated from T(ty), T(sk)) were significantly lower after summer-SA than that of winter-SA. Sweat onset time was delayed during winter-SA compared to that after summer-SA. BMR, AXR(1), AXR(2), and DIR sweat rates, ASGD and ASGO, and evaporative loss volume were significantly diminished after winter-SA relative to after summer-SA. In conclusion, changes in sweating activity measured by QSART confirmed the involvement of the peripheral nervous system in variation of sudomotor activity in seasonal acclimation.
Acclimatization* ; Acetylcholine ; Axons ; Basal Metabolism ; Body Temperature ; Humans* ; Iontophoresis ; Peripheral Nervous System ; Reflex ; Republic of Korea ; Seasons* ; Skin Temperature ; Sweat ; Sweat Glands ; Sweating