Effects of acute aerobic exercise on arterial stiffness in transgender men

Testosterone replacement therapy (TRT) in transgender men (TM) results in side effects such as elevated triglycerides and increased arterial stiffness. Exercise may be useful to ameliorate such effects, but no studies have examined the effects of acute aerobic exercise in TM. This study aimed to investigate the effects of acute aerobic exercise on arterial stiffness in TM. Thirty-six participants were included, comprising 12 TM (duration of TRT: 57.4 ± 30.3 months), 12 males and 12 females. All participants performed acute aerobic exercise on a treadmill at 50% heart rate reserve for 30 min. Arterial stiffness as measured by brachial-ankle pulse wave velocity (baPWV) was measured before exercise (Pre), 30 min after exercise (Post30), and 60 min after exercise (Post60). Serum sex hormone levels, and serum lipid profile were determined only before exercise. Serum low-density lipoprotein cholesterol (LDL-C) levels before exercise were significantly higher in TM than in males or females (males: p < 0.01; females: p < 0.05). At all points, baPWV in TM was significantly higher than in females (p < 0.05) and significantly lower than in males (p < 0.05). However, when comparing changes in baPWV over time in each group, significant decreases in Post30 and Post60 were seen in males compared to Pre (both p < 0.05), but no significant change after aerobic exercise was seen in TM or females. These results suggest that acute aerobic exercise yield different effects in TM than in males, but is unlikely to reduce arterial stiffness in TM receiving TRT

ムシュウ ニンニク 2カゲツカン ノ セッシュ ハ ウンドウ ユウハツセイ IL-6 ジョウショウ ヲ ヨクセイ スル：ゼンゴ ヒカク シケン

ニンニクに含まれるアリシンはヒトで運動誘発性インターロイキン（IL）6産生を抑制することが報告されている。しかし，アリシンは特有の強い臭気を持つため，実生活を考えると日常的に使用することが難しい。我々はそこで，無臭ニンニク（odorless garlic ; OG）2か月間摂取が運動誘発性IL-6産生と他の免疫応答を減弱する可能性について検討することを目的とした。日頃からあまり活動的でない6名の健康な男性（22.0±0.7歳）を対象に一日当たり1 gのOGを2か月間にわたって摂取させた。研究での運動負荷条件は推定最大心拍数の80％強度の自転車運動とし，45分間実施した。運動負荷は，実験開始前（control群 ; CON-Ex）とニンニク摂取2か月後（odorless garlic supplementation and exercise群 ; OG-Ex）に実施した。血液サンプルは運動負荷を行う前，運動負荷直後（0 min），30分後，60分後に採取し，IL-6，IL-10，白血球数，好中球数，リンパ球数，Natural Killer Cell Activity （NKCA），コルチゾールを測定した。運動負荷前から運動負荷60分後までの上昇曲線下面積（iAUC）を算出し，統計解析には繰り返しのある二元配置分散分析（ANOVA）およびHolm’s methodを用いた対応のあるt検定を行った。運動負荷前の生化学値にはCON-ExとOG-Exの間に有意な差は見られなかった。運動負荷後の白血球数，好中球数，リンパ球数，NKCA，IL-10，およびコルチゾールに交互作用は見られなかったものの，IL-6には交互作用が見られた（p＝0.011）。OG-Ex 群の運動誘発性IL-6 iAUC値はCON-Ex群に比べて有意な低下がみられた（CON-Ex, 82.5±12.2 min･pg/mL ; OG-Ex, 55.5±14.2 min･pg/mL ; p＝0.018）。今回の結果は2か月間のOG摂取が運動誘発性IL-6上昇を抑制するという仮説を支持する結果となった。しかしながら，OG摂取は他の免疫指標に影響を及ぼすことはなかった。OG摂取が運動誘発性の免疫機能に及ぼす影響については，今後のさらなる研究が必要である。Allicin, which is a primary compound in crushed garlic, inhibits exercise-induced interleukin (IL)-6 production in humans. However, the daily use of crushed garlic or stabilized allicin is not practical due to the strong odor of allicin. We therefore investigated the possibility that odorless garlic (OG) supplementation for 2 months attenuates exercise-induced IL-6 and other immunological responses. Six healthy untrained men (aged 22.0±0.7 years) consumed 1 g of OG per day for 2 months. Participants underwent two 45-min periods of acute cycling exercise at 80% intensity of heart rate reserve (HRR). The first period was at baseline (control exercise ; CON-Ex) and the second after 2 months of OG supplementation (odorless garlic supplementation and exercise ; OG-Ex). To assess levels of IL-6, IL-10, leukocytes, neutrophils, lymphocytes, Natural Killer Cell Activity (NKCA) and cortisol, blood samples were collected before and immediately (0 min), and 30 and 60 min after each 45-min period of exercise. Two-way repeated measures analysis of variance (ANOVA) and paired t-test with Holm’s method were performed, and the incremental area under the curve (iAUC) from before to 60 min after exercise was calculated. No significant differ­ences in the pre-exercise levels of biochemical indices were observed between the CON-Ex and OG-Ex assessments. No significant interaction effects were observed in exercise-induced changes in leukocytes, neutrophils, lymphocytes, NKCA, IL-10, or cortisol. A significant interaction effect was observed in exercise-induced changes in IL-6 (p＝0.011). OG consumption also significantly decreased the iAUC of IL-6 (CON-Ex, 82.5±12.2 min･pg/mL ; OG-Ex, 55.5±14.2 min･pg/mL ; p＝0.018). Our findings support the hypothesis that two months of OG supplementation attenuates exercise-induced increases in IL-6 levels among untrained men. However, OG did not exert a similar effect on other immunological parameters. Further study is required to clarify the effect of OG on exercise-induced activation of the immune system

Menstrual cycle effects on exercise-induced fatigability

Estrogen and progesterone have distinct concentrations across the menstrual cycle, each one promoting several physiological alterations other than preparing the uterus for pregnancy. Whether these physiological alterations can influence motor output during a fatiguing contraction is the goal of this review, with an emphasis on the obtained effect sizes. Studies on the topic frequently attempt to report if there is a statistical significant difference in fatigability between the follicular and luteal phases of the menstrual cycle. Although the significant difference (P value) can inform the probability of the event, it does not indicate the magnitude of it. We also investigated whether type of task performed (e.g., isometric vs. dynamic) can further influence the magnitude by which exercise-induced fatigue changes with fluctuations in the concentration of ovarian hormones. We retrieved experimental studies in eumenorrheic women published between 1975 and 2019. The initial search yielded 920 studies and after manual refinement, 46 experimental studies that reported metrics of motor output in both the follicular and luteal phases of the menstrual cycle were included. From these retrieved studies, 15 showed a statistical difference between the luteal and follicular phases (7 showing less fatigability during the luteal phase and 8 during the follicular phase). The effect size was not consistent across studies and with a large range (-6.77; 1.61, favoring the luteal and follicular phase respectively). The inconsistencies across studies may be a consequence of the differences in the limb used during the fatiguing contraction (upper vs. lower extremity), type of contraction (isometric vs. dynamic), the muscle mass engaged (single limb vs. full body), and the techniques used to define menstrual cycle phase (e.g. serum concentration vs. reported day of menses). Further studies are required to determine the effects of regular menstrual cycle phase on the exercise-induced fatigability.Financial support was provided from the Office of the Vice President for Research and Partnerships and the Office of the Provost, the University of Oklahoma – Norman Campus. Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye

Prevalence and associated factors of stress fractures, menstrual dysfunction, and eating disorders in high school athletes

Abstract: Objective: Stress fractures (SF), menstrual dysfunction (MD), and eating disorders (ED) in young athletes are important issues. We conducted this study to determine the frequency of SF, MD, and ED experienced by high school track and field athletes in Japan and to understand the factors associated with them. Materials and Methods: A cross-sectional study of 1199 high level high school track and field athletes (608 males and 591 females) who participated in a selective training camp held by the Japan Association of Athletics Federations. Results: Approximately one in four male and female athletes self-reported SF. Moreover, we identified the length of the practice time per week and the event (sprinting, middle-distance, jumping, and combined) as relevant factors. Approximately one in three female athletes self-reported MD history, with those participating in long-distance events experiencing it significantly more frequently than those participants in sprinting, throwing, and jumping events. Furthermore, we identified ED history and long-distance events as MD history-related factors. ED history was self-reported at low frequency without gender difference, and long-distance was significantly more frequently reported than sprinting and jumping. Conclusions: About a quarter of Japanese high school track and field athletes experience SF, and about a third of the females experience MD. The association of these with athletic events, training time, and ED should be considered

The Influence of Low Energy Availability on Bone Mineral Density and Trabecular Bone Microarchitecture of Pubescent Female Athletes : A Preliminary Study

The influence of low energy availability (LEA) on bone mineral density (BMD) and trabecular bone microarchitecture in pubescent female athletes is unclear. This study aimed to investigate the influence of LEA on BMD and trabecular bone microarchitecture in 21 pubescent female athletes (age, 12-15 years; 11 track and field athletes, 10 gymnasts). We used two indices to assess LEA: energy availability and the percent of ideal body weight. Dual-energy X-ray absorptiometry was used to obtain total body less head, lumbar spine BMD Z-scores, and lumbar trabecular bone scores (TBS). Pearson's or Spearman's correlation coefficients were used to assess the relationship among EA, percent of ideal body weight, and bone parameters. The threshold for statistical significance was set at p < 0.05. The percent of ideal body weight was significantly correlated with the BMD Z-scores of the total body less head (r = 0.61; p < 0.01), lumbar spine (r = 0.55; p < 0.01), and lumbar TBS (r = 0.47; p = 0.03). However, energy availability was not correlated with bone parameters. These findings suggest that screening for low ideal body weight may be a useful predictor of low BMD and insufficient trabecular bone microarchitecture in pubescent female athletes

Proteomics of appetite-regulating system influenced by menstrual cycle and intensive exercise in female athletes: a pilot study

Abstract Female athletes who endure intense training are at risk of developing the 'female athlete triad,' making energy intake management crucial. However, the fluctuations in estradiol and progesterone levels throughout the menstrual cycle present a challenge in maintaining consistent energy intake. This study aimed to uncover the underlying factors associated with appetite regulation linked to menstrual phases and exercise using proteomic approach. Five female athletes engaged in 60 min of bicycle exercise, followed by 90 min of rest, during both the follicular and luteal phases. Serum samples were collected before, during, and after exercise, and the serum proteome was analyzed using 2D-gel electrophoresis. A total of 511 spots were detected in the subjects' serum profiles, with significant decreases observed in haptoglobin during the luteal phase and complement component 3 during bicycle training. Unsupervised learning with a generalized estimating equation analysis showed that serum peptide YY (PYY), an appetite suppressor, significantly influenced the fluctuations of serum proteins induced by exercise (p < 0.05). Regression analysis demonstrated a positive correlation between PYY and serum IgM (R = 0.87), implying that the intestinal environment and the immune response in female athletes may contribute to appetite regulation

In Vivo Imaging of Hierarchical Spatiotemporal Activation of Caspase-8 during Apoptosis.

[Background]: Activation of caspases is crucial for the execution of apoptosis. Although the caspase cascade associated with activation of the initiator caspase-8 (CASP8) has been investigated in molecular and biochemical detail, the dynamics of CASP8 activation are not fully understood. [Methodology/Principal Findings]: We have established a biosensor based on fluorescence resonance energy transfer (FRET) for visualizing apoptotic signals associated with CASP8 activation at the single-cell level. Our dual FRET (dual-FRET) system, comprising a triple fusion fluorescent protein, enabled us to simultaneously monitor the activation of CASP8 and its downstream effector, caspase-3 (CASP3) in single live cells. With the dual-FRET-based biosensor, we detected distinct activation patterns of CASP8 and CASP3 in response to various apoptotic stimuli in mammalian cells, resulting in the positive feedback amplification of CASP8 activation. We reproduced these observations by in vitro reconstitution of the cascade, with a recombinant protein mixture that included procaspases. Furthermore, using a plasma membrane-bound FRET-based biosensor, we captured the spatiotemporal dynamics of CASP8 activation by the diffusion process, suggesting the focal activation of CASP8 is sufficient to propagate apoptotic signals through death receptors. [Conclusions]: Our new FRET-based system visualized the activation process of both initiator and effector caspases in a single apoptotic cell and also elucidated the necessity of an amplification loop for full activation of CASP8