The effect of 12 weeks of aerobic exercise training with or without saffron supplementation on diabetes-specific markers and inflammation in women with type 2 diabetes: A randomized double-blind placebo-controlled trial.

This study was conducted to investigate the effects of 12 weeks of aerobic exercise (AT) and saffron supplementation on hemostasis, inflammatory markers, and insulin resistance in obese women diagnosed with type 2 diabetes (T2D). A total of 44 women with T2D (mean age: 54.12 ± 5.63 years, mean BMI: 31.15 ± 1.50 kg/m2, HbA1c: 85 ± 4.2 mmol/mol) were included in a randomized, double-blind, placebo-controlled study. We were randomly assigned to one of four groups (n = 11 per group): saffron + training (ST), placebo + training (PT), saffron supplement (SS), and placebo (P). The ST and PT groups completed 12 weeks of AT (three sessions per week of mild to moderate intensity). The ST and SS groups were administered a daily dose of 200 mg of saffron powder for 12 weeks. Fasting blood samples were collected 48 h before the first AT session and/or nutritional supplementation and 48 h after the last AT session and/or nutritional supplementation. Post-evaluation, homeostatic model assessment of insulin resistance value (HOMA-IR, p < 0.001) and serum levels of glucose (p < 0.001), fibrinogen (FIB, p < 0.001), homocysteine (HCY, p < 0.001), interleukin-6 (IL-6, p < 0.001), and tumor necrosis factor α (TNFα, p < 0.001) showed significant reduction in the ST, PT, and SS groups compared to the P group (p < 0.05). In particular, the ST group showed a more significant reduction in all variables compared to the PT and SS groups (p < 0.05). Our results suggest that a 12-week intervention with AT and saffron supplementation can independently improve markers related to hemostasis, inflammation, and insulin resistance. However, their combination showed the greatest effectiveness on the above markers.

Lactate-induced autophagy activation: unraveling the therapeutic impact of high-intensity interval training on insulin resistance in type 2 diabetic rats.

Impaired autophagy is a hallmark of diabetes. The current study proposed to investigate if high intensity interval training (HIIT) induced lactate accumulation could stimulate autophagy in type 2 diabetic male rats. 28 male Wistar rats were randomly assigned into four groups: Healthy Control (CO), Diabetes Control (T2D), Exercise (EX), and Diabetes + Exercise (T2D + EX). Diabetes was induced by feeding high-fat diet and administrating single dose of streptozotocin (35 mg/kg). After becoming diabetic, the animals in the exercise groups (EX and T2D + EX) performed an eight-week HIIT (4-10 interval, 80-100% Vmax, 5 days per week). Serum levels of lactate, glucose and insulin as well as the levels of lactate, pyruvate, lactate transporter monocarboxylate transporter 1 (MCT1), phosphorylated mitogen-activated protein kinases (p-MAP 1 and 2), phosphorylated extracellular signal-regulated protein kinases 1 and 2 (p-ERK 1 and 2), mammalian target of rapamycin (p-mTOR), ribosomal protein S6 kinase beta-1 (p-70S6k), p90 ribosomal S6 kinases (p-90RSK), autophagy related 7 (ATG7), Beclin-1, microtubule-associated protein 1A/1B, and 2A/2B -light chain 3 levels (LC3-I), (LC3- II), (LC3I/LC3II) in soleus muscle were measured. Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and serum glucose was lower in T2D + EX compared to T2D group (P < 0.0001). While serum and soleus muscle levels of lactate was not different between T2D and T2D + Ex, the levels of Pyruvate (P < 0.01), MCT1, p-ERK1/2, p-mTOR, p70S6k, P-90RSK, ATG7, LC3-II, and LC3-II/LC3I ratios were higher in T2D + EX compared to T2D group (P < 0.0001). We concluded that eight weeks of high-intensity interval training could activated ERK/P90SRK while inhibiting mTOR/P70S6K signaling pathway in lactate dependent manner. It means increased autophagy which resulted in improve insulin resistance (IR) and reduce blood glucose.

Beneficial Mitochondrial Biogenesis in Gastrocnemius Muscle Promoted by High-Intensity Interval Training in Elderly Female Rats.

OBJECTIVE: Exercise can attenuate mitochondrial dysfunction caused by aging. Our study aimed to compare 12 weeks of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on the expression of mitochondria proteins [e.g., AMP-activated protein kinase (AMPK), Estrogen-related receptor alpha (ERRα), p38 mitogen-activated protein kinase (P38MAPK), and Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1-α)] in gastrocnemius muscle of old female rats. MATERIALS AND METHODS: In this experimental study, thirty six old female Wistar rats (18-month-old and 270-310 g) were divided into three groups: i. HIIT, ii. MICT, and iii. Control group (C). The HIIT protocol was performed for 12 weeks with 16-28 minutes (2 minutes training with 85-90% VO2max in high intensity and 2 minutes training with 45-75% VO2max low intensity). The MICT was performed for 30-60 minutes with the intensity of 65-70% VO2max. The gastrocnemius muscle expression of AMPK, ERRα, P38MAPK, and PGC1α proteins were determined by Western blotting. RESULTS: The expression of AMPK (P=0.004), P38MAPK (P=0.003), PGC-1α (P=0.028), and ERRα (P=0.006) in HIIT was higher than C group. AMPK (P=0.03), P38MAPK (P=0.032), PGC-1α (P=0.015), and ERRα (P=0.028) in MICT was higher than the C group. Also expression of AMPK (P=0.008), P38MAPK (P=0.009), PGC-1α (P=0.020) and ERRα (P=0.014) in MICT was higher than MICT group. CONCLUSION: It seems that exercise training has beneficial effects on mitochondrial biogenesis, but the HIIT training method is more effective than MICT in improving mitochondrial function in aging.