Association of adiponectin gene single nucleotide polymorphisms with environmental risk factors in type 2 diabetes mellitus: An updated evidence of haplotype-based analysis study.

BACKGROUND AND AIM: Adiponectin (ADIPOQ) gene is considered to be one of the promising players in deciphering the genetic bases of type 2 diabetes. This study investigated the associations between haplotype combinations of three single nucleotide polymorphisms (SNPs) of the ADIPOQ gene and two SNPs of the ADIPOQ receptor genes with environmental risk factors for the prediction of T2DM disorder susceptibility in the Iranian population. METHODS: This case-control and cross-sectional study was conducted on 182 patients with T2DM and 155 healthy controls. Genotyping was performed using amplification refractory mutation system-PCR (ARMS-PCR) for rs17300539G/A, rs2241766T/G, and rs1501299G/T of the ADIPOQ gene, rs1342387C/T of the AdipoR1 gene, and rs10773989T/C of the AdipoR2 gene. RESULTS: All polymorphisms met the Hardy-Weinberg equilibrium (p > 0.05). The studied SNPs; rs17300539, rs2241766 of ADIPOQ gene and rs10773989of AdipoR2 gene, were significantly associated with increased risk of T2DM. Two-way ANOVA analysis indicated that GG carriers of rs2241766T/G had a significantly lower waist-to-hip ratio and body mass index compared to TT carriers, and also GG of rs2241766T/G showed the greatest HbA1c levels compared to any other genotype. CC carriers of rs10773989T/C displayed a significantly higher LDL level compared to the other two genotype carries. According to Combined Haplotype ([rs17300539, rs2241766, rs1501299] / [rs17300539, rs2241766, rs1501299]) analysis, GTT- homozygote carriers displayed the highest plasma adiponectin levels. In contrast, GGG/GTG, ATG/GTG, and GGG/GGG showed the lowest plasma adiponectin levels in the controls. CONCLUSION: The adiponectin gene haplotype combinations were associated with plasma adiponectin concentrations in healthy people. In T2DM, adiponectin genetic variants displayed less effect on adiponectin plasma concentrations.

Comparison of Measurements of External Load between Professional Soccer Players.

Background: The excessive and rapid increases in training load (TL) may be responsible for most non-contact injuries in soccer. This study's aims were to describe, week(w)-by-week, the acute (AW), chronic (CW), acute:chronic workload ratio (wACWR), total distance (wTD), duration training (wDT), sprint total distance (wSTD), repeat sprint (wRS), and maximum speed (wMS) between starter and non-starter professional soccer players based on different periods (i.e., pre-, early-, mid-, and end-season) of a full-season (Persian Gulf Pro League, 2019−2020). Methods: Nineteen players were divided according to their starting status: starters (n = 10) or non-starters (n = 9). External workload was monitored for 43 weeks: pre- from w1−w4; early- from w5−w17; mid- from w18−w30, and end-season from w31−w43. Results: In starters, AW, CW, and wACWR were greater than non-starters (p < 0.05) throughout the periods of early- (CW, p ≤ 0.0001), mid- (AW, p = 0.008; CW, p ≤ 0.0001; wACWR, p = 0.043), or end-season (AW, p = 0.035; CW, p = 0.017; wACWR, p = 0.010). Starters had a greater wTD (p ≤ 0.0001), wSTD (p ≤ 0.0001 to 0.003), wDT (p ≤ 0.0001 to 0.023), wRS (p ≤ 0.0001 to 0.018), and wMS (p ≤ 0.0001) than non-starters during early-, mid-, and end-season. Conclusion: Starters experienced more CW and AW during the season than non-starters, which underlines the need to design tailored training programs accounting for the differences between playing status.

The Effects of TRX Suspension Training Combined with Taurine Supplementation on Body Composition, Glycemic and Lipid Markers in Women with Type 2 Diabetes.

BACKGROUND: We aimed to investigate the effects of an 8-week total-body resistance exercise (TRX) suspension training intervention combined with taurine supplementation on body composition, blood glucose, and lipid markers in T2D females. METHODS: Forty T2D middle-aged females (age: 53 ± 5 years, body mass = 84.3 ± 5.1 kg) were randomly assigned to four groups, TRX suspension training + placebo (TP; n = 10), TRX suspension training + taurine supplementation (TT; n = 10), taurine supplementation (T; n = 10), or control (C; n = 10). Body composition (body mass, body mass index (BMI), body fat percentage (BFP)), blood glucose (fasting blood sugar (FBS)), hemoglobin A1c (HbA1c), Insulin, and Insulin resistance (HOMA-IR), and lipid markers (low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglyceride (TG), and total cholesterol (TC)) were evaluated prior to and after interventions. RESULTS: All three interventions significantly decreased body mass, BMI, and BFP with no changes between them for body mass and BMI; however, BFP changes in the TT group were significantly greater than all other groups. FBS was significantly reduced in TP and TT. Insulin concentrations' decrement were significantly greater in all experimental groups compared to C; however, no between group differences were observed between TT, TP, and T. In regards to HOMA-IR, decreases in TT were significantly greater than all other groups TG, HbA1c, and LDL were reduced following all interventions. HDL values significantly increased only in the TT group, while TC significantly decreased in TP and TT groups. Changes in HbA1c, TG, HDL, and TC were significantly greater in the TT compared to all other groups. CONCLUSIONS: TRX training improved glycemic and lipid profiles, while taurine supplementation alone failed to show hypoglycemic and hypolipidemic properties. Notably, the synergic effects of TRX training and taurine supplementation were shown in HbA1c, HOMA-IR, TG, TC, HDL, and BFP changes. Our outcomes suggest that TRX training + taurine supplementation may be an effective adjuvant therapy in individuals with T2D.

Role of melatonin in the angiogenesis potential; highlights on the cardiovascular disease.

Melatonin possesses multi-organ and pleiotropic effects with potency to control angiogenesis at both molecular and cellular levels. To date, many efforts have been made to control and regulate the dynamic of angiogenesis modulators in a different milieu. The term angiogenesis or neovascularization refers to the development of de novo vascular buds from the pre-existing blood vessels. This phenomenon is tightly dependent on the balance between the pro- and anti-angiogenesis factors which alters the functional behavior of vascular cells. The promotion of angiogenesis is thought to be an effective strategy to accelerate the healing process of ischemic changes such as infarcted myocardium. Of note, most of the previous studies have focused on the anti-angiogenesis capacity of melatonin in the tumor niche. To the best of our knowledge, few experiments highlighted the melatonin angiogenesis potential and specific regulatory mechanisms in the cardiovascular system. Here, we aimed to summarize some previous experiments related to the application of melatonin in cardiovascular diseases such as ischemic injury and hypertension by focusing on the regulatory mechanisms.

Melatonin and prolonged physical activity attenuated the detrimental effects of diabetic condition on murine cardiac tissue.

In this study, the combined effects of four-week swimming training and melatonin were examined on the oxidative response, inflammation, apoptosis, and angiogenesis capacity of cardiac tissue in the mouse model of diabetes. The mice were randomly allocated into five groups (n = 10 per group) as follows: Control; Diabetic group; Diabetic + Melatonin group; Diabetic + Exercise group; and Diabetic + Exercise + Melatonin group. 50 mg/kg streptozotocin was intraperitoneally administrated. In melatonin-treated groups, melatonin was injected intraperitoneally at 3 mg/kg body weight for four weeks and twice weekly. Swimming exercises were performed for four weeks. We measured cardiac superoxide dismutase, glutathione peroxidase enzymes, malondialdehyde, and total antioxidant capacity. The expression of tumor necrosis factor-α, Caspase­3, Sirtuin1, and Connexin-43 was measured using real-time PCR analysis. The vascular density was analyzed by immunohistochemistry using CD31 and α-smooth muscle actin antibodies. The combination of melatonin and exercise elevated cardiac superoxide dismutase, glutathione peroxidase coincided with the reduction of malondialdehyde and increase of total antioxidant capacity as compared to the diabetic mice (p < 0.05). In Diabetic + Exercise + Melatonin mice, tumor necrosis factor-α, Caspase­3 was significantly down-regulated compared to the Diabetic group (p < 0.05). Melatonin and exercise suppressed the expression of Connexin-43 and Sirtuin1 in diabetic mice in comparison with the control mice (p < 0.05). H & E staining showed necrosis and focal hyperemia reduction in the Diabetic + Exercise + Melatonin group compared to the Diabetic group. Data showed a decrease of CD31+ and α-smooth muscle actin+ vessels in the Diabetic group as compared to the normal samples (p < 0.05). The number of CD31+ vessels, but not α-smooth muscle actin+ type, increased in the Diabetic + Exercise + Melatonin group compared to the Diabetic mice. These data demonstrated that exercise along with melatonin administration could diminish the detrimental effects of diabetes on cardiac tissue via using different mechanisms.

Effects of Running on Sand vs. Stable Ground on Kinetics and Muscle Activities in Individuals With Over-Pronated Feet.

Background: In terms of physiological and biomechanical characteristics, over-pronation of the feet has been associated with distinct muscle recruitment patterns and ground reaction forces during running. Objective: The aim of this study was to evaluate the effects of running on sand vs. stable ground on ground-reaction-forces (GRFs) and electromyographic (EMG) activity of lower limb muscles in individuals with over-pronated feet (OPF) compared with healthy controls. Methods: Thirty-three OPF individuals and 33 controls ran at preferred speed and in randomized-order over level-ground and sand. A force-plate was embedded in an 18-m runway to collect GRFs. Muscle activities were recorded using an EMG-system. Data were adjusted for surface-related differences in running speed. Results: Running on sand resulted in lower speed compared with stable ground running (p < 0.001; d = 0.83). Results demonstrated that running on sand produced higher tibialis anterior activity (p = 0.024; d = 0.28). Also, findings indicated larger loading rates (p = 0.004; d = 0.72) and greater vastus medialis (p < 0.001; d = 0.89) and rectus femoris (p = 0.001; d = 0.61) activities in OPF individuals. Controls but not OPF showed significantly lower gluteus-medius activity (p = 0.022; d = 0.63) when running on sand. Conclusion: Running on sand resulted in lower running speed and higher tibialis anterior activity during the loading phase. This may indicate alterations in neuromuscular demands in the distal part of the lower limbs when running on sand. In OPF individuals, higher loading rates together with greater quadriceps activity may constitute a proximal compensatory mechanism for distal surface instability.

Analysis of Fitness Status Variations of Under-16 Soccer Players Over a Season and Their Relationships With Maturational Status and Training Load.

The purposes of this study were (i) to analyze the variations in maximal oxygen consumption (VO2m ax), maximal heart rate (HRmax), heart rate at rest, acceleration, maximal speed, agility, anaerobic sprint test (RAST) of peak power (RPP), RAST of minimum power, RAST of average power (RAP), and RAST of fatigue index (RFI) during the competitive season, using maturation status and accumulated training load as covariates, and (ii) to describe the differences between responders and non-responders in relation to baseline levels. Twenty-three elite players from the same team competing in the national under-16 competitions were evaluated for 20 weeks in period 1 (before league), middle (mid league), and period 2 (after league). The VO2m ax (p = 0.009), maximal speed (p = 0.001), RPP (p < 0.001), RAP (p < 0.001), and RFI (p < 0.001) significantly changed across the assessment periods. Interestingly, using accumulated training load and maturation status as covariates revealed no statistical significance (p > 0.05). When analyzing responders and non-responders, only HRmax (between periods 1 and 2) showed no differences between the groups. As a conclusion, it can be seen that accumulated training load and maturation status play an important role in the differences observed across the season. Thus, coaches should consider the importance of these two factors to carefully interpret fitness changes in their players and possibly adjust training decisions according to the maturation level of the players.

Ground reaction forces and muscle activity while walking on sand versus stable ground in individuals with pronated feet compared with healthy controls.

BACKGROUND: Sand is an easy-to-access, cost-free resource that can be used to treat pronated feet (PF). Therefore, the aims of this study were to contrast the effects of walking on stable ground versus walking on sand on ground reaction forces (GRFs) and electromyographic (EMG) activity of selected lower limb muscles in PF individuals compared with healthy controls. METHODS: Twenty-nine controls aged 22.2±2.5 years and 30 PF individuals aged 22.2±1.9 years were enrolled in this study. Participants walked at preferred speed and in randomized order over level ground and sand. A force plate was included in the walkway to collect GRFs. Muscle activities were recorded using EMG system. RESULTS: No statistically significant between-group differences were found in preferred walking speed when walking on stable ground (PF: 1.33±0.12 m/s; controls: 1.35±0.14 m/s; p = 0.575; d = 0.15) and sand (PF: 1.19±0.11 m/s; controls: 1.23±0.18 m/s; p = 0.416; d = 0.27). Irrespective of the group, walking on sand (1.21±0.15 m/s) resulted in significantly lower gait speed compared with stable ground walking (1.34±0.13 m/s) (p<0.001; d = 0.93). Significant main effects of "surface" were found for peak posterior GRFs at heel contact, time to peak for peak lateral GRFs at heel contact, and peak anterior GRFs during push-off (p<0.044; d = 0.27-0.94). Pair-wise comparisons revealed significantly smaller peak posterior GRFs at heel contact (p = 0.005; d = 1.17), smaller peak anterior GRFs during push-off (p = 0.001; d = 1.14), and time to peak for peak lateral GRFs (p = 0.044; d = 0.28) when walking on sand. No significant main effects of "group" were observed for peak GRFs and their time to peak (p>0.05; d = 0.06-1.60). We could not find any significant group by surface interactions for peak GRFs and their time to peak. Significant main effects of "surface" were detected for anterior-posterior impulse and peak positive free moment amplitude (p<0.048; d = 0.54-0.71). Pair-wise comparisons revealed a significantly larger peak positive free moment amplitude (p = 0.010; d = 0.71) and a lower anterior-posterior impulse (p = 0.048; d = 0.38) when walking on sand. We observed significant main effects of "group" for the variable loading rate (p<0.030; d = 0.59). Pair-wise comparisons revealed significantly lower loading rates in PF compared with controls (p = 0.030; d = 0.61). Significant group by surface interactions were observed for the parameter peak positive free moment amplitude (p<0.030; d = 0.59). PF individuals exhibited a significantly lower peak positive free moment amplitude (p = 0.030, d = 0.41) when walking on sand. With regards to EMG, no significant main effects of "surface", main effects of "group", and group by surface interactions were observed for the recorded muscles during the loading and push-off phases (p>0.05; d = 0.00-0.53). CONCLUSIONS: The observed lower velocities during walking on sand compared with stable ground were accompanied by lower peak positive free moments during the push-off phase and loading rates during the loading phase. Our findings of similar lower limb muscle activities during walking on sand compared with stable ground in PF together with lower free moment amplitudes, vertical loading rates, and lower walking velocities on sand may indicate more relative muscle activity on sand compared with stable ground. This needs to be verified in future studies.

Moderate aerobic exercise training decreases middle-aged induced pathologic cardiac hypertrophy by improving Klotho expression, MAPK signaling pathway, and oxidative stress status in Wistar rats.

OBJECTIVES: This study aimed to investigate the effect of aerobic training on serum levels of Klotho, cardiac tissue levels of H2O2 and phosphorylation of ERK1/2 and P38 as well as left ventricular internal diameter (LVID), the left ventricle wall thickness (LVWT) and fibrosis in middle-aged rats. MATERIALS AND METHODS: Forty wistar rats, including young rats (n=10, 4 month-old) and middle-aged rats (n=30, 13-15 months-old) were enrolled in this experimental study. The all young and 10 middle-aged rats were sacrificed (randomly) under deep anesthesia without any exercise training as normal young control and normal middle-aged control respectively. The remaining 20 middle-aged rats participated in 4 (n=10) or 8-week (n=10) aerobic exercise training. RESULTS: There were significant differences in the plasmatic Klotho levels and the heart tissue levels of phosphorylated-ERK1/2 (p-ERK1/2), P-P38 and H2O2, LVWT, LVID and fibrosis between young and middle-aged rats (P=0.01). Plasmatic Klotho level was significantly increased after eight weeks training (P=0.011). Also, p-ERK1/2 was significantly decreased after eight weeks and p-P38 was significantly decreased in the fourth (P=0.01) and eight weeks of training (P=0.01). A similar decrease was reported for aging-induced H2O2 in the fourth (P=0.016) and eighth weeks (P=0.001). LVID was significantly increased in eight weeks, but LVWT and fibrosis was significantly reduced in the eighth week (P=0.011, P=0.028, P=0.001 respectively). CONCLUSION: Moderate aerobic training attenuates aging-induced pathological cardiac hypertrophy at least partially by restoring the Klotho levels, attenuating oxidative stress, and reduction in the phosphorylation of ERK1/2, P38 and fibrosis.

Narita target heart rate equation underestimates the predicted adequate exercise level in sedentary young boys.

PURPOSE: Optimal training intensity and the adequate exercise level for physical fitness is one of the most important interests of coaches and sports physiologists. The aim of this study was to investigate the validity of the Narita et al target heart rate equation for the adequate exercise training level in sedentary young boys. METHODS: Forty two sedentary young boys (19.07±1.16 years) undertook a blood lactate transition threshold maximal treadmill test to volitional exhaustion with continuous respiratory gas measurements according to the Craig method. The anaerobic threshold (AT) of the participants then was calculated using the Narita target heart rate equation. RESULTS: Hopkin's spreadsheet to obtain confidence limit and the chance of the true difference between gas measurements and Narita target heart rate equation revealed that the Narita equation most likely underestimates the measured anaerobic threshold in sedentary young boys (168.76±15 vs. 130.08±14.36) (Difference ±90% confidence limit: 38.1±18). Intraclass correlation coefficient (ICC) showed a poor agreement between the criterion method and Narita equation (ICC= 0.03). CONCLUSION: According to the results, the Narita equation underestimates the measured AT. It seems that the Narita equation is a good predictor of aerobic not AT which can be investigated in the future studies.

Is the cardiorespiratory fitness affected by height of young girls?

The purpose of the present study was to examine the effect of height in the predicted VO2max by the Queens Step test among short and tall young girls. A sample of 38 individuals was selected in two stages from a total of 500 individuals and was assigned to two groups of short (n = 20) and tall (n = 18). In order to examine the effect of height in the predicted VO2max, the Queens step protocol and the incremental treadmill speed test were used. Respiratory exchange was measured continuously throughout the test by an automated open-circuit gas analysis system. The study results showed that tall girls revealed a higher VO2max on the Queen's step and treadmill tests than short girls (Queen's: 44.09+/-2.66 vs. 38.96+/-1.65; Treadmill: 34.03+/-7.26 vs. 28.15+/-5.09 mL/kg/min). Based on the obtained findings it can be concluded that the higher VO2max seen in tall girls on the both protocols, may be due to their physiological and physical properties; therefore, it seems that designing of the adjustable steps to the height of subjects for optimizing the estimation of VO2max is not necessary and other physiological factors may be involved, which require further investigation.