OBJECTIVES: Due to poor treatment adherence and lifestyle-based interventions, chronic hypertension is a dominant risk factor predisposing individuals to heart failure and malignant arrhythmias. We investigated the impact of the postnatal acclimation of hairless SHR to ambient temperature that is, for them, below thermoneutrality, on the electrical coupling protein connexin-43 (Cx43) and pro-fibrotic markers in both heart ventricles of male and female hairless SHR rats compared to the wild SHR. METHODS: Some 6-month-acclimated male and female hairless SHR as well as age- and sex-matched wild SHR were included and compared with the non-hypertensive Wistar strain. The left and right heart ventricles were examined for Cx43 topology, myocardial structure, and the histochemistry of capillaries. The protein levels of Cx43, relevant protein kinases, and extracellular matrix proteins (ECMs) were determined by immunoblotting. MMP-2 activity was assessed via zymography, and susceptibility to malignant arrhythmias was tested ex vivo. RESULTS: Cx43 and its phosphorylated variant pCx43368 were significantly reduced in the left heart ventricles of wild SHR males, while to a lesser extent in the hairless SHR. In contrast, these proteins were not significantly altered in the right heart ventricles of males or in both heart ventricles in females, regardless of the rat strain. Pro-arrhythmic Cx43 topology was detected in the left heart ventricle of wild SHR and to a lesser extent in hairless SHR males. TGFβ protein was significantly increased only in the left ventricle of the wild SHR males. MMP-2 activity was increased in the right ventricle but not in the left ventricles of both males and females, regardless of the rat strain. CONCLUSIONS: The findings indicate that the postnatal acclimation of hairless SHR to ambient temperature hampers the downregulation of Cx43 in the left heart ventricle compared to wild SHR males. The decline of Cx43 was much less pronounced in females and not observed in the right heart ventricles, regardless of the rat strain. It may impact the susceptibility of the heart to malignant arrhythmias.

• MeSH
• Acclimatization MeSH
• Down-Regulation MeSH
• Hypertension * metabolism   MeSH
• Connexin 43 * metabolism   genetics   MeSH
• Rats MeSH
• Rats, Inbred SHR * MeSH
• Rats, Wistar MeSH
• Arrhythmias, Cardiac * metabolism   etiology   MeSH
• Heart Ventricles * metabolism   MeSH
• Temperature * MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

The mammalian body possesses remarkable adaptability to cold exposure, involving intricate adjustments in cellular metabolism, ultimately leading to thermogenesis. However, cold-induced stress can impact immune response, primarily through noradrenaline-mediated pathways. In our study, we utilized a rat model subjected to short-term or long-term mild cold exposure to investigate systemic immune response during the cold acclimation. To provide human relevance, we included a group of regular cold swimmers in our study. Our research revealed complex relationship between cold exposure, neural signaling, immune response, and thermogenic regulation. One-day cold exposure triggered stress response, including cytokine production in white adipose tissue, subsequently activating brown adipose tissue, and inducing thermogenesis. We further studied systemic immune response, including the proportion of leukocytes and cytokines production. Interestingly, γδ T cells emerged as possible regulators in the broader systemic response, suggesting their possible contribution in the dynamic process of cold adaptation. We employed RNA-seq to gain further insights into the mechanisms by which γδ T cells participate in the response to cold. Additionally, we challenged rats exposed to cold with the Toll-like receptor 2 agonist, showing significant modulation of immune response. These findings significantly contribute to understanding of the physiological acclimation that occur in response to cold exposure.

• MeSH
• Acclimatization immunology   MeSH
• Cytokines metabolism   MeSH
• Adipose Tissue, Brown immunology   metabolism   MeSH
• Rats MeSH
• Humans MeSH
• Cold Temperature * MeSH
• Receptors, Antigen, T-Cell, gamma-delta immunology   metabolism   MeSH
• T-Lymphocytes immunology   MeSH
• Thermogenesis immunology   MeSH
• Toll-Like Receptor 2 * metabolism   genetics   immunology   MeSH
• Inflammation * immunology   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Humans MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

Horakova, Lenka, Susi Kriemler, Vladimír Študent, Jacqueline Pichler Hefti, David Hillebrandt, Dominique Jean, Kastė Mateikaitė-Pipirienė, Peter Paal, Alison Rosier, Marija Andjelkovic, Beth Beidlemann, Mia Derstine, and Linda E. Keyes. Hormonal contraception and menstrual cycle control at high altitude: a scoping review-UIAA Medical Commission recommendations. High Alt Med Biol. 25:255-265, 2024. Background: Women who use hormonal contraception (HC) may have questions about their use during travel to high altitude. This scoping review summarizes current evidence on the efficacy and safety of HC and cycle control during high-altitude travel. Methods: We performed a scoping review for the International Climbing and Mountaineering Federation (UIAA) Medical Commission series on Women's Health in the Mountains. Pertinent literature from PubMed and Cochrane was identified by keyword search combinations (including contraception) with additional publications found by hand search. Results: We identified 17 studies from 7,165 potentially eligible articles. No articles assessed the efficacy of contraception during a short-term high-altitude sojourn. Current data show no advantage or disadvantage in HC users for acclimatization or acute mountain sickness (AMS). Use of HC during high-altitude travel is common and safe for menses suppression. A potential concern of estrogen-containing HC is the increased thrombotic risk, which theoretically could be compounded in hypobaric hypoxia. Conclusions: Evidence is limited for the interaction of HC and high altitude on performance, thrombosis, and contraceptive efficacy. HC does not affect the risk of AMS. The most efficacious and safest method at high altitude is generally the one women are most familiar with and already using.

• MeSH
• Hormonal Contraception methods   MeSH
• Mountaineering physiology   MeSH
• Humans MeSH
• Menstrual Cycle * physiology   drug effects   MeSH
• Altitude * MeSH
• Check Tag
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

The extreme environments of the Tibetan Plateau offer considerable challenges to human survival, demanding novel adaptations. While the role of biological and agricultural adaptations in enabling early human colonization of the plateau has been widely discussed, the contribution of pastoralism is less well understood, especially the dairy pastoralism that has historically been central to Tibetan diets. Here, we analyze ancient proteins from the dental calculus (n = 40) of all human individuals with sufficient calculus preservation from the interior plateau. Our paleoproteomic results demonstrate that dairy pastoralism began on the highland plateau by ~3500 years ago. Patterns of milk protein recovery point to the importance of dairy for individuals who lived in agriculturally poor regions above 3700 m above sea level. Our study suggests that dairy was a critical cultural adaptation that supported expansion of early pastoralists into the region's vast, non-arable highlands, opening the Tibetan Plateau up to widespread, permanent human occupation.

• MeSH
• Acclimatization MeSH
• Humans MeSH
• Dairying * MeSH
• Occupations MeSH
• Agriculture * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Tibet MeSH

• MeSH
• Acclimatization physiology   MeSH
• Humans MeSH
• Pre-Exposure Prophylaxis MeSH
• Risk Factors MeSH
• Altitude Sickness * pathology   prevention & control   MeSH
• Check Tag
• Humans MeSH

Previous research shows the beneficial effects of an intradialytic resistance training (IRT) on muscle function in haemodialysis patients. However, patients vary highly in their functional responses to IRT, may be due to effects of age and sex heterogeneities in adaptation. Therefore, the aim of this study was to investigate the degree to which the effects of IRT on the muscle function of haemodialysis patients vary by age and sex. We included 57 patients who completed a 12-week IRT (EXG) and 33 patients who received no IRT (CNG) during haemodialysis. Muscle function (MF) was assessed using dynamometry before and after a 12-week intervention and after a 12-week follow-up. After the 12-week intervention, we found a moderation effect of age in the relative (%) change (p = 0.011) and absolute (Δ) change (p = 0.027) of MF, and a moderation effect of sex in %MF (p = 0.001), but not in ΔMF (p = 0.069). Regarding patients' age, the change of MF was only significantly different between EXG and CNG patients aged 60-70 years (%MF, EXG: + 34.6%, CNG: - 20.1%, p < 0.001; ΔMF, EXG: + 44.4 N, CNG: - 22.1 N, p < 0.001). Regarding patients' sex, the change of MF was only significantly different between EXG and CNG female patients (%MF, EXG: + 23.9%, CNG: - 23.6%, p < 0.001). Age and sex did not significantly moderate changes in MF measures after 12 weeks of follow-up. We conclude that both age and sex of haemodialysis patients affect their functional response to IRT in the short term.Trial Registration: Intradialytic Resistance Training in Haemodialysis Patients (IRTHEP)-#NCT03511924, 30/04/2018, https://clinicaltrials.gov/ct2/show/NCT03511924 .

• MeSH
• Acclimatization MeSH
• Genetic Heterogeneity MeSH
• Middle Aged MeSH
• Humans MeSH
• Resistance Training * MeSH
• Sex Characteristics * MeSH
• Aged MeSH
• Muscles MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Publikace se zaměřuje na otužování, jeho fyziologii a jeho prospěšné účinky na lidské zdraví, zejména na snížení stresu a posílení výkonnosti. Určeno široké veřejnosti.; Pomocí bezpečného otužování a správného dýchání se lze trvale zbavit celé řady fyzických i psychických obtíží. Neurovědkyně ukazuje, jak využít blahodárné účinky chladu na naše tělo i mysl.

• Keywords
• otužování,
• MeSH
• Acclimatization MeSH
• Complementary Therapies MeSH
• Cryotherapy * MeSH
• Cold Temperature MeSH
• Health Promotion MeSH
• Stress, Psychological MeSH
• Efficiency MeSH
• Health Behavior MeSH
• Publication type
• Monograph MeSH
• Popular Work MeSH

• Conspectus
• Fyzioterapie. Psychoterapie. Alternativní lékařství
• NML Fields
• rehabilitační a fyzikální medicína
• zdravotní výchova

Life underground has constrained the evolution of subterranean mammals to maximize digging performance. However, the mechanisms modulating morphological change and development of fossorial adaptations in such taxa are still poorly known. We assessed the morpho-functional diversity and early postnatal development of fossorial adaptations (bone superstructures) in the appendicular system of the African mole-rats (Bathyergidae), a highly specialized subterranean rodent family. Although bathyergids can use claws or incisors for digging, all genera presented highly specialized bone superstructures associated with scratch-digging behavior. Surprisingly, Heterocephalus glaber differed substantially from other bathyergids, and from fossorial mammals by possessing a less specialized humerus, tibia and fibula. Our data suggest strong functional and developmental constraints driving the selection of limb specializations in most bathyergids, but more relaxed pressures acting on the limbs of H. glaber. A combination of historical, developmental and ecological factors in Heterocephalus are hypothesized to have played important roles in shaping its appendicular phenotype.

• MeSH
• Acclimatization * MeSH
• Phenotype MeSH
• Adaptation, Physiological MeSH
• Mole Rats * MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

The infarct size-limiting effect elicited by cold acclimation (CA) is accompanied by increased mitochondrial resistance and unaltered β1-adrenergic receptor (AR) signaling persisting for 2 wk at room temperature. As the mechanism of CA-elicited cardioprotection is not fully understood, we examined the role of the salvage β2-AR/Gi/Akt pathway. Male Wistar rats were exposed to CA (8°C, 5 wk), whereas the recovery group (CAR) was kept at 24°C for additional 2 wk. We show that the total number of myocardial β-ARs in the left ventricular myocardium did not change after CA but decreased after CAR. We confirmed the infarct size-limiting effect in both CA and CAR groups. Acute administration of β2-AR inhibitor ICI-118551 abolished the protective effect in the CAR group but had no effect in the control and CA groups. The inhibitory Giα1/2 and Giα3 proteins increased in the membrane fraction of the CAR group, and the phospho-Akt (Ser473)-to-Akt ratio also increased. Expression, phosphorylation, and mitochondrial location of the Akt target glycogen synthase kinase (GSK-3β) were affected neither by CA nor by CAR. However, GSK-3β translocated from the Z-disk to the H-zone after CA, and acquired its original location after CAR. Our data indicate that the cardioprotection observed after CAR is mediated by the β2-AR/Gi pathway and Akt activation. Further studies are needed to unravel downstream targets of the central regulators of the CA process and the downstream targets of the Akt protein after CAR.NEW & NOTEWORTHY Cardioprotective effect of cold acclimation and that persisting for 2 wk after recovery engage in different mechanisms. The β2-adrenoceptor/Gi pathway and Akt are involved only in the mechanism of infarct size-limiting effect occurring during the recovery phase. GSK-3β translocated from the Z-line to the H-zone of sarcomeres by cold acclimation returns back to the original position after the recovery phase. The results provide new insights potentially useful for the development of cardiac therapies.

• MeSH
• Acclimatization MeSH
• Receptors, Adrenergic, beta-2 MeSH
• Phosphorylation MeSH
• Glycogen Synthase Kinase 3 beta MeSH
• Rats MeSH
• Rats, Wistar MeSH
• Proto-Oncogene Proteins c-akt metabolism   MeSH
• Myocardial Reperfusion Injury * MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

Publikace se zaměřuje na Wim Hofovu metodu posilování zdraví pomocí zejména otužování a dechových cvičení a zároveň je biografií Wim Hofa. Určeno široké veřejnosti.; Praktická kniha s konkrétními návody pro všechny, kteří chtějí praktikovat metodu Wima Hofa. Včetně 30denní výzvy pro ty, kteří s metodou teprve začínají.

• MeSH
• Acclimatization MeSH
• Breathing Exercises MeSH
• History, 20th Century MeSH
• History, 21st Century MeSH
• Cryotherapy MeSH
• Cold Temperature MeSH
• Health Promotion MeSH
• Psychophysiology MeSH
• Athletes MeSH
• Famous Persons MeSH
• Health Behavior MeSH
• Check Tag
• History, 20th Century MeSH
• History, 21st Century MeSH
• Publication type
• Biography MeSH
• Popular Work MeSH

• Conspectus
• Fyzioterapie. Psychoterapie. Alternativní lékařství
• NML Fields
• alternativní lékařství
• rehabilitační a fyzikální medicína
• preventivní medicína

• About
• Hof, Wim, 1959- Authority