Browsing by Author "Chung, Eunhee"

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Annatto-extracted tocotrienols improve glucose homeostasis and bone properties in high-fat diet-induced type 2 diabetic mice by decreasing the inflammatory response
(2018) Shen, Chwan Li (TTUHSC); Kaur, Gurvinder (TTUHSC); Wanders, Desiree; Sharma, Shaligram; Tomison, Michael D. (TTUHSC); Ramalingam, Latha (TTU); Chung, Eunhee; Moustaid-Moussa, Naima (TTU); Mo, Huanbiao; Dufour, Jannette M. (TTUHSC)
Diabetes is a risk factor for osteoporosis. Annatto-extracted tocotrienols (TT) have proven benefits in preserving bone matrix. Here, we evaluated the effects of dietary TT on glucose homeostasis, bone properties, and liver pro-inflammatory mRNA expression in high-fat diet (HFD)-induced type 2 diabetic (T2DM) mice. 58 male C57BL/6 J mice were divided into 5 groups: low-fat diet (LFD), HFD, HFD + 400 mgTT/kg diet (T400), HFD + 1600 mgTT/kg diet (T1600), and HFD + 200 mg metformin/kg (Met) for 14 weeks. Relative to the HFD group, both TT-supplemented groups (1) improved glucose homeostasis by lowering the area under the curve for both glucose tolerance and insulin tolerance tests, (2) increased serum procollagen I intact N-terminal propeptide (bone formation) level, trabecular bone volume/total volume, trabecular number, connectivity density, and cortical thickness, (3) decreased collagen type 1 cross-linked C-telopeptide (bone resorption) levels, trabecular separation, and structure model index, and (4) suppressed liver mRNA levels of inflammation markers including IL-2, IL-23, IFN-γ, MCP-1, TNF-α, ITGAX and F4/80. There were no differences in glucose homeostasis and liver mRNA expression among T400, T1600, and Met. The order of osteo-protective effects was LFD ≥T1600 ≥T400 = Met >HFD. Collectively, these data suggest that TT exerts osteo-protective effects in T2DM mice by regulating glucose homeostasis and suppressing inflammation.
Effect of Dietary Geranylgeraniol and Green Tea Polyphenols on Glucose Homeostasis, Bone Turnover Biomarkers, and Bone Microstructure in Obese Mice
(2023) Shen, Chwan Li (TTUHSC); Dufour, Jannette M. (TTUHSC); Miranda, Jonathan M. (TTUHSC); Kaur, Gurvinder (TTUHSC); Chung, Eunhee; Ramalingam, Latha (TTU); Moustaid-Moussa, Naima (TTU); Cao, Jay J.
Previously, we demonstrated that the administration of either geranylgeraniol (GGOH) or green tea polyphenols (GTP) improved bone health. This study examined the combined effects of GGOH and GTP on glucose homeostasis in addition to bone remodeling in obese mice. We hypothesized that GGOH and GTP would have an additive or synergistic effect on improving glucose homeostasis and bone remodeling possibly in part via suppression of proinflammatory cytokines. Forty-eight male C57BL/6J mice were assigned to a high-fat diet (control), HFD + 400 mg GGOH/kg diet (GG), HFD + 0.5% GTP water (TP), or HFD + GGOH + GTP (GGTP) diet for 14 weeks. Results demonstrated that GTP supplementation improved glucose tolerance in obese mice. Neither GGOH nor GTP affected pancreas insulin or bone formation procollagen type I intact N-terminal, bone volume at the lumbar vertebrae, or bone parameters at the trabecular bone and cortical bone of the femur. There was an interactive effect for serum bone resorption collagen type 1 cross-linked C-telopeptide concentrations, resulting in no-GGOH and no-GTP groups having the highest values. GGOH increased trabecular number and decreased trabecular separation at the lumbar vertebrae. GTP increased trabecular thickness at lumbar vertebrae. The GG group produced the greatest connectivity density and the lowest structure model index. Only GTP, not GGOH, decreased adipokines concentrations (resistin, leptin, monocyte chemoattractant protein-1, and interleukin-6). In an obese male mouse model, individual GGOH and GTP supplementation improved glucose homeostasis, serum CTX, and trabecular microstructure of LV-4. However, the combined GGOH and GTP supplementation compromises such osteoprotective effects on serum CTX and trabecular bone of obese mice.
Effects of high-intensity resistance training on circulating levels of irisin in healthy adults: A randomized controlled trial
(2018) Fernandez-Del-Valle, Maria; Short, Matthew J. (TTU); Chung, Eunhee; McComb, Jacalyn (TTU); Kloiber, Shelby (TTU); Naclerio, Fernando; Larumbe-Zabala, Eneko (TTUHSC)
Background: Existing research suggests that irisin increases in response to exercise in humans. However, results are controversial and a majority of the studies lack a control group. The present study aimed to analyze the effects of both one-bout, and three-week intense resistance training on physical fitness (body composition and strength) and serum irisin levels when compared to a control group. Methods: A total of 26 healthy young adults (n = 14 males; 12 females) completed the pre-assessment phase, and were randomly assigned to either intervention or control group. Physical activity, diet, and physical fitness (strength, cardiorespiratory fitness, and body composition) were assessed. Blood samples were collected at baseline, during and post one-bout of exercise, and baseline on sessions 1, 3, 6 and 9 of 3-week high intensity resistance training (3 times per week). Results: None of the ANOVA effects on irisin concentration were significant after one-bout of exercise or 3 weeks of resistance training. The intervention group showed large significant changes from pre to post in relative body fat (%BF) (t (13) =-3.37, P = 0.003), and lean body mass (P = 0.016, d = 0.72). All muscle strength variables (1RM bench press (F (1,22) = 19.54, P < 0.001, η2G < 0.01); 1RM leg press (F (1,22) = 20.84, P < 0.001, η2G= 0.03); bench press-to-body weight ratio (F (1,22) = 18.93, P < 0.001, η2G = 0.01); leg press-to-body weight ratio (F (1,22) = 23.03, P < 0.001, η2G = 0.05)) showed significant group by time interaction effects. Conclusions: Serum irisin concentrations did not change during or post one-bout, nor during three-weeks of high-intensity resistance training compared to matched controls, while the program elicited significant changes in body composition and muscle strength in a group of healthy young adults. Only irisin levels in the control group were significantly increased. Additionally, no significant associations were found between irisin levels and physical activity, diet, or physical fitness. However, negative associations were found between baseline serum irisin concentrations and body composition (body weight and skeletal muscle mass) in males.
Geranylgeraniol and Green Tea Polyphenols Mitigate Negative Effects of a High-Fat Diet on Skeletal Muscle and the Gut Microbiome in Male C57BL/6J Mice
(2022) Shen, Chwan Li; Elmassry, Moamen M. (TTU); Grue, Katherine (TTU); Joiner, Hayli E. (TTU); Jacobo, A. Unique (TTU); Hamood, Abdul; Chung, Eunhee
Natural bioactive compounds are proposed as alternatives in mitigating obesity-associated skeletal muscle dysfunction. The objective of this study was to test the hypothesis that the combination of geranylgeraniol (GGOH) and green tea polyphenols (GTPs) can alleviate high-fat-diet (HFD)-induced muscle atrophy and alter gut microbiome composition. Male C57BL/6J mice fed an HFD were assigned to four groups (12 mice each) in a 2 (no GGOH vs. 400 mg GGOH/kg diet) × 2 (no GTPs vs. 0.5% weight/volume GTPs in water) factorial design. After 14 weeks of diet intervention, skeletal muscle and cecal samples were collected and examined. Compared to the control groups, the group that consumed a combination of GGOH and GTPs (GG + GTPs) had significantly decreased body and fat mass but increased skeletal muscle mass normalized by body weight and cross-sectional area. In soleus muscle, the GG + GTP diet increased citrate synthase activity but decreased lipid peroxidation. Gut microbiome beta-diversity analysis revealed a significant difference in the microbiome composition between diet groups. At the species level, the GG + GTP diet decreased the relative abundance of Dorea longicatena, Sporobacter termitidis, and Clostridium methylpentosum, and increased that of Akkermansia muciniphila and Subdoligranulum variabile. These results suggest that the addition of GGOH and GTPs to an HFD alleviates skeletal muscle atrophy, which is associated with changes in the gut microbiome composition.
Metabolic benefits of annatto-extracted tocotrienol on glucose homeostasis, inflammation, and gut microbiome
(2020) Chung, Eunhee; Elmassry, Moamen M. (TTU); Kottapalli, Pratibha; Kottapalli, Kameswara Rao; Kaur, Gurvinder (TTUHSC) (TTU); Dufour, Jannette M. (TTUHSC) (TTU); Wright, Kandis (TTUHSC); Ramalingam, Latha (TTUHSC) (TTU); Moustaid-Moussa, Naima (TTUHSC) (TTU); Wang, Rui (TTUHSC); Hamood, Abdul N. (TTUHSC); Shen, Chwan Li (TTUHSC) (TTU)
Emerging evidence suggests that the gut microbiome plays an important role in the pathophysiology of both obesity and type 2 diabetes mellitus. We previously reported that dietary annatto-extracted tocotrienol exerts beneficial effects by modulating inflammatory responses in mice fed a high-fat diet (HFD). The purpose of this study was to test the hypothesis that tocotrienol supplementation when combined with an HFD would result in an altered gut microbiota composition. For 14 weeks, forty-eight male C57BL/6J mice were assigned to 4 groups—low-fat diet, HFD, HFD supplemented with annatto-extracted tocotrienol at 800 mg/kg diet (AT), and HFD supplemented with metformin at 200 mg/kg diet. Glucose homeostasis was assessed by glucose and insulin tolerance tests, serum and pancreas insulin levels, and histological assessments of insulin and glucagon in pancreatic tissue. The concentrations of adipokines were measured in white adipose tissues. For the gut microbiome analysis, cecal content was collected, DNA was extracted, and 16S rRNA gene sequencing was performed. AT supplementation improved glucose homeostasis and lowered resistin, leptin, and interleukin-6 levels in white adipose tissue. Relative to the HFD group, AT-supplemented mice showed a decrease in the Firmicutes to Bacteroidetes ratio and had a lower abundance of Ruminococcus lactaris, Dorea longicatena, and Lachnospiraceae family. The relative abundance of Akkermansia muciniphila was increased in the AT group compared to the low-fat diet group. The association between the metabolic improvements and the identified bacterial taxa suggests a potential metabolic modulation caused by AT supplementation through the gut microbiota composition in mice fed an HFD.
The AKT/FOXO3A/Atrogin - 1 signaling pathways underlying cardiac regression after detraining in a mouse heart
(2013-12) Lee, Wanseok; Chung, Eunhee; Park, Yoonjung; Gonzales, Joaquin U.
Exercise-induced cardiac hypertrophy reverses after cessation of exercise training. The Akt/FoxO3a/Atrogin-1 pathways have been implicated as important players in skeletal and cardiac muscle atrophy. However, little is known about the role of these pathways in cardiac muscle regression after exercise cessation. Thus, the purpose of this study was to determine the activities of Akt, FoxO, and to measure the levels of the muscle-specific E3 ligase, Atrogin-1 in cardiac muscle which has undergone regression of mass after cessation of exercise training. Three to four month old male C57Bl/6 mice were randomly divided into six groups: sedentary controls, 21 days of exercise, and 4 different time points of detraining after 21 days of voluntary wheel running (ie. 3 days, 5 days, 14 days, and 21 days). Body weight was not significantly different among groups. Exercise training significantly increased the heart weight/body weight ratio compared to sedentary controls (13% increase in HW/BW), but this growth was regressed after 21 days of detraining. We found that phosphorylation of Akt normalized to total Akt was significantly increased in the exercise group, and also in the 3-, 5-, and 14 days of detraining groups, but was significantly decreased in the 21 days of detraining group compared to the sedentary control group. However, the phospho-FoxO3a to total FoxO3a ratio was not different among groups. Interestingly, the level of Atrogin-1 was significantly decreased in 14-, and 21 days of detraining groups. Our results suggest that cardiac regression following exercise cessation is not mediated by up-regulation of Atrogin-1. Taken together, this study demonstrates that cardiac regression occurs after 21 days of exercise cessation and it may be partially mediated by inactivation of Akt.