Metformin Impairs Mitochondrial Function in Skeletal Muscle of Both Lean and Diabetic Rats in a Dose-Dependent Manner

Skeletal muscles are high-insulin tissues responsible for disposing of glucose via the highly regulated process of facilitated glucose transporter 4 (GLUT4). Impaired insulin action in diabetes, as well as disorders of GLUT4 vesicle trafficking in the muscle, are involved in defects in insulin-stimulated GLUT4 translocation. Since the Rab GTPases are the main regulators of vesicular membrane transport in exo- and endo-cytosis, in the present work, we studied the effect of olive leaf polyphenols (OLPs) on Rab8A, Rab13, and Rab14 proteins of the rat soleus muscle in a model of streptozotocin (SZT)-induced diabetes (DM) in a dose-dependent manner. Glucose, cholesterol, and triglyceride levels were determined in the blood, morphological changes of the muscle tissue were captured by hematoxylin and eosin histological staining, and expression of GLUT4, Rab8A, Rab13, and Rab14 proteins were analyzed in the rat soleus muscle by the immunofluorescence staining and immunoblotting. OLPs significantly reduced blood glucose level in all treated groups. Furthermore, significantly reduced blood triglycerides were found in the groups with the lowest and highest OLPs treatment. The dynamics of activation of Rab8A, Rab13, and Rab14 was OLPs dose-dependent and more effective at higher OLP doses. Thus, these results indicate a beneficial role of phenolic compounds from the olive leaf in the regulation of glucose homeostasis in the skeletal muscle.

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Atorvastatin impairs liver mitochondrial function in obese Göttingen Minipigs but heart and skeletal muscle are not affected

Scientific Reports ◽

10.1038/s41598-021-81846-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Liselotte Bruun Christiansen ◽

Tine Lovsø Dohlmann ◽

Trine Pagh Ludvigsen ◽

Ewa Parfieniuk ◽

Michal Ciborowski ◽

...

Keyword(s):

Skeletal Muscle ◽

Mitochondrial Function ◽

Citrate Synthase ◽

Obese Group ◽

Control Group ◽

Dependent Manner ◽

Respiratory Capacity ◽

Protein Carbonyl Content ◽

Functional Changes ◽

Mitochondrial Respiratory

AbstractStatins lower the risk of cardiovascular events but have been associated with mitochondrial functional changes in a tissue-dependent manner. We investigated tissue-specific modifications of mitochondrial function in liver, heart and skeletal muscle mediated by chronic statin therapy in a Göttingen Minipig model. We hypothesized that statins enhance the mitochondrial function in heart but impair skeletal muscle and liver mitochondria. Mitochondrial respiratory capacities, citrate synthase activity, coenzyme Q10 concentrations and protein carbonyl content (PCC) were analyzed in samples of liver, heart and skeletal muscle from three groups of Göttingen Minipigs: a lean control group (CON, n = 6), an obese group (HFD, n = 7) and an obese group treated with atorvastatin for 28 weeks (HFD + ATO, n = 7). Atorvastatin concentrations were analyzed in each of the three tissues and in plasma from the Göttingen Minipigs. In treated minipigs, atorvastatin was detected in the liver and in plasma. A significant reduction in complex I + II-supported mitochondrial respiratory capacity was seen in liver of HFD + ATO compared to HFD (P = 0.022). Opposite directed but insignificant modifications of mitochondrial respiratory capacity were seen in heart versus skeletal muscle in HFD + ATO compared to the HFD group. In heart muscle, the HFD + ATO had significantly higher PCC compared to the HFD group (P = 0.0323). In the HFD group relative to CON, liver mitochondrial respiration decreased whereas in skeletal muscle, respiration increased but these changes were insignificant when normalizing for mitochondrial content. Oral atorvastatin treatment in Göttingen Minipigs is associated with a reduced mitochondrial respiratory capacity in the liver that may be linked to increased content of atorvastatin in this organ.

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Effect of lemon peel flavonoids on anti-fatigue and anti-oxidation capacities of exhaustive exercise mice

Applied Biological Chemistry ◽

10.1186/s13765-020-00573-3 ◽

2020 ◽

Vol 63 (1) ◽

Author(s):

Guili Bao ◽

Yinglong Zhang ◽

Xiaoguang Yang

Keyword(s):

Skeletal Muscle ◽

Superoxide Dismutase ◽

Manganese Superoxide Dismutase ◽

Fatty Acid Content ◽

Hepatic Tissue ◽

Control Group ◽

Dependent Manner ◽

Lemon Peel ◽

Tnf Α ◽

Dose Dependent

AbstractIn this study, lemon peel flavonoids (LPF) were administered to investigate its effect on the anti-fatigue and antioxidant capacity of mice that undergo exercise until exhaustion. LPF (88.36 min in LPFH group mice) significantly increased the exhaustion swimming time compare to the untreated mice (40.36 min), increased the liver glycogen and free fatty acid content in mice and reduce lactic acid and BUN content in a dose-dependent manner. As the concentration of lemon peel flavonoids increased, the serum creatine kinase, aspartate aminotransferase, and alanine aminotransferase levels of mice gradually decreased. LPF increases superoxide dismutase (SOD) and catalase (CAT) levels in mice and reduces malondialdehyde levels in a dose-dependent manner. And LPF raises hepatic tissue SOD, CAT activities and reduces skeletal muscle tissue iNOS, TNF-α levels of mice compared to the control group. LPF also enhanced the expression of copper/zinc-superoxide dismutase (Cu/Zn-SOD), manganese-superoxide dismutase (Mn-SOD), and CAT mRNA in mouse liver tissue. LPF also enhanced the expression of alanine/serine/cysteine/threonine transporter 1 (ASCT1) mRNA and attenuate the expression of syncytin-1, inducible nitric oxide synthase (iNOS), and tumor necrosis factor (TNF)-α in mouse skeletal muscle. According to high-performance liquid chromatography (HPLC) analysis, it was found that LPF contains flavonoids such as rutin, astragalin, isomangiferin, naringin, and quercetin. Our experimental data show that LPF has good anti-fatigue effects and anti-oxidation ability. In summary, LPF has high prospects to be developed and added to nutritional supplements.

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PROTECTIVE ROLE OF FICUS RACEMOSA IN DIABETES INDUCED NEUROPATHY: STRUCTURAL AND FUNCTIONAL EVIDENCES

INDIAN DRUGS ◽

10.53879/id.54.11.10855 ◽

2017 ◽

Vol 54 (11) ◽

pp. 58-60

Author(s):

N Solanki ◽

◽

S. K Bhavsar

Keyword(s):

Sciatic Nerve ◽

Diabetic Neuropathy ◽

Ethanolic Extract ◽

Protective Role ◽

Diabetic Rats ◽

Dependent Manner ◽

Traditional System ◽

Ficus Racemosa ◽

Dose Dependent

Ficus racemosa is used in traditional system of medicine for various health problems and diseases, and is commonly known as Gular fig. The main objective was to study its effects against streptozotocin induced diabetic neuropathy by structural and functional marker. Investigation of diabetic neuropathy was carried out through functional and structural assessment in streptozotocin induced in diabetic rats. Diabetic rats were treated for 28 days in dose dependent manner of Ficus racemosa aqueous extract (250 mg/kg and 500 mg/kg) and ethanolic extract (200 mg/kg and 400 mg/kg). Study showed marked protection observed by Ficus racemosa in hippocampus region of brain and sciatic nerve tissues. Ficus racemosa treatment showed improvement in functional and structural markers, which strongly suggest its protective role in diabetic neuropathy.

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AMP-activated protein kinase activity and glucose uptake in rat skeletal muscle

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.2001.280.5.e677 ◽

2001 ◽

Vol 280 (5) ◽

pp. E677-E684 ◽

Cited By ~ 152

Author(s):

Nicolas Musi ◽

Tatsuya Hayashi ◽

Nobuharu Fujii ◽

Michael F. Hirshman ◽

Lee A. Witters ◽

...

Keyword(s):

Skeletal Muscle ◽

Protein Kinase ◽

Glucose Uptake ◽

Muscle Contractions ◽

Treadmill Running ◽

Dependent Manner ◽

Rat Skeletal Muscle ◽

Amp Activated Protein Kinase ◽

Dose Dependent

The AMP-activated protein kinase (AMPK) has been hypothesized to mediate contraction and 5-aminoimidazole-4-carboxamide 1-β-d-ribonucleoside (AICAR)-induced increases in glucose uptake in skeletal muscle. The purpose of the current study was to determine whether treadmill exercise and isolated muscle contractions in rat skeletal muscle increase the activity of the AMPKα1 and AMPKα2 catalytic subunits in a dose-dependent manner and to evaluate the effects of the putative AMPK inhibitors adenine 9-β-d-arabinofuranoside (ara-A), 8-bromo-AMP, and iodotubercidin on AMPK activity and 3- O-methyl-d-glucose (3-MG) uptake. There were dose-dependent increases in AMPKα2 activity and 3-MG uptake in rat epitrochlearis muscles with treadmill running exercise but no effect of exercise on AMPKα1 activity. Tetanic contractions of isolated epitrochlearis muscles in vitro significantly increased the activity of both AMPK isoforms in a dose-dependent manner and at a similar rate compared with increases in 3-MG uptake. In isolated muscles, the putative AMPK inhibitors ara-A, 8-bromo-AMP, and iodotubercidin fully inhibited AICAR-stimulated AMPKα2 activity and 3-MG uptake but had little effect on AMPKα1 activity. In contrast, these compounds had absent or minimal effects on contraction-stimulated AMPKα1 and -α2 activity and 3-MG uptake. Although the AMPKα1 and -α2 isoforms are activated during tetanic muscle contractions in vitro, in fast-glycolytic fibers, the activation of AMPKα2-containing complexes may be more important in regulating exercise-mediated skeletal muscle metabolism in vivo. Development of new compounds will be required to study contraction regulation of AMPK by pharmacological inhibition.

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Cannabidiol Modulates Mitochondrial Redox and Dynamics in MCF7 Cancer Cells: A Study Using Fluorescence Lifetime Imaging Microscopy of NAD(P)H

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.630107 ◽

2021 ◽

Vol 8 ◽

Author(s):

Rhys Richard Mould ◽

Stanley W. Botchway ◽

James R. C. Parkinson ◽

Elizabeth Louise Thomas ◽

Geoffrey W Guy ◽

...

Keyword(s):

Cancer Cells ◽

Fluorescence Lifetime ◽

Mitochondrial Function ◽

Mode Of Action ◽

Fluorescence Lifetime Imaging Microscopy ◽

Mitochondrial Morphology ◽

Fluorescence Lifetime Imaging ◽

Dependent Manner ◽

Lifetime Imaging ◽

Dose Dependent

The cannabinoid, cannabidiol (CBD), is part of the plant's natural defense system that when given to animals has many useful medicinal properties, including activity against cancer cells, modulation of the immune system, and efficacy in epilepsy. Although there is no consensus on its precise mode of action as it affects many cellular targets, CBD does appear to influence mitochondrial function. This would suggest that there is a cross-kingdom ability to modulate stress resistance systems that enhance homeostasis. As NAD(P)H autofluorescence can be used as both a metabolic sensor and mitochondrial imaging modality, we assessed the potential of this technique to study the in vitro effects of CBD using 2-photon excitation and fluorescence lifetime imaging microscopy (2P-FLIM) of NAD(P)H against more traditional markers of mitochondrial morphology and cellular stress in MCF7 breast cancer cells. 2P-FLIM analysis revealed that the addition of CBD induced a dose-dependent decrease in bound NAD(P)H, with 20 µM treatments significantly decreased the contribution of bound NAD(P)H by 14.6% relative to the control (p < 0.001). CBD also increased mitochondrial concentrations of reactive oxygen species (ROS) (160 ± 53 vs. 97.6 ± 4.8%, 20 µM CBD vs. control, respectively, p < 0.001) and Ca2+ (187 ± 78 vs. 105 ± 10%, 20 µM CBD vs. the control, respectively, p < 0.001); this was associated with a significantly decreased mitochondrial branch length and increased fission. These are all suggestive of mitochondrial stress. Our results support the use of NAD(P)H autofluorescence as an investigative tool and provide further evidence that CBD can modulate mitochondrial function and morphology in a dose-dependent manner, with clear evidence of it inducing oxidative stress at higher concentrations. This continues to support emerging data in the literature and may provide further insight into its overall mode of action, not only in cancer, but potentially its function in the plant and why it can act as a medicine.

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Comment on “Photobiomodulation delays the onset of skeletal muscle fatigue in a dose-dependent manner”

Lasers in Medical Science ◽

10.1007/s10103-018-2504-y ◽

2018 ◽

Vol 33 (7) ◽

pp. 1617-1618

Author(s):

Thiago De Marchi

Keyword(s):

Skeletal Muscle ◽

Muscle Fatigue ◽

Dependent Manner ◽

Skeletal Muscle Fatigue ◽

Dose Dependent

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Antidiabetic and antioxidative properties of the hydro-methanolic extract (60:40) of rhizomes of Curcuma amada roxb. (Zingiberaceae) in streptozotocin-induced diabetic male albino rat: a dose-dependent study through biochemical and genomic approaches

Journal of Complementary and Integrative Medicine ◽

10.1515/jcim-2017-0182 ◽

2019 ◽

Vol 16 (4) ◽

Cited By ~ 1

Author(s):

Dipanwita Mitra ◽

Riya Sarkar ◽

Debidas Ghosh

Keyword(s):

Body Weight ◽

Methanolic Extract ◽

Fasting Blood Glucose ◽

Diabetic Rats ◽

Diabetic Group ◽

Dependent Manner ◽

Male Adult ◽

Curcuma Amada ◽

Corrective Effect ◽

Dose Dependent

Abstract Background Curcuma amada is the most popular traditional medicine in India for the treatment of diabetes. The present study aimed to focus the antidiabetic and antioxidative activity of C. amada through the analysis of biochemical and genomic levels in a dose-dependent manner in streptozotocin-induced male adult rat. Method Streptozotocin-induced diabetic rats were administered orally with hydro-methanolic extract of C. amada at the dose of 10, 20, 40 and 80 mg/100 g body weight of rats for 28 days. The antidiabetic and antioxidative efficacy of the extract on glycemic, enzymatic, genomic and histological sensors along with toxicity study was investigated. Results The result showed a significant antidiabetic and antioxidative effect of the extract at dose-dependent manner. The significant recovery of fasting blood glucose level, serum insulin, activity of carbohydrate metabolic enzymes and antioxidative enzymes in extract-treated diabetic group as compared to untreated diabetic group were noted. After the extract treatment, the size of pancreatic islet and cell population densities were significantly increased. Activities of glutamate oxaloacetate transaminase and glutamate pyruvate transaminase in liver were significantly recovered along with the correction of Bax and Bcl-2 gene expression in hepatic tissue after the extract treatment in diabetic rats in respect to untreated diabetic group. Out of all the doses, the significant effects were noted at the dose of 20 mg/100 g body weight which has been considered as threshold dose in the concern. Conclusion It may be concluded that the significant and corrective effect in most of the sensors was noted at the minimum dose of 20 mg/100 g body weight of hydro-methanolic extract of C. amada without producing any toxicity.

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Antioxidant and Antidiabetic Effect of Hibiscus rosasinensis Flower Extract on Streptozotocin Induced Experimental Rats-a Dose Response Study

Notulae Scientia Biologicae ◽

10.15835/nsb346348 ◽

2011 ◽

Vol 3 (4) ◽

pp. 13-21 ◽

Cited By ~ 5

Author(s):

Mirunalini SANKARAN ◽

Arulmozhi VADIVEL

Keyword(s):

Diabetic Rats ◽

Antioxidant Effect ◽

Dependent Manner ◽

Enzymatic Antioxidants ◽

Control Groups ◽

Metabolizing Enzymes ◽

Detailed Mechanism ◽

Flower Extract ◽

Dose Response Study ◽

Dose Dependent

The present study was designed to evaluate the antidiabetic and antioxidant effect of Hibiscus rosasinensis against streptozotocin induced diabetic rats. Streptozotocin (STZ) was administered as a single dose (40 mg/kg) to induce diabetes. The hypoglycemic activity of Hibiscus rosasinensis extract (HRSEt) was investigated in a dose dependent manner such as (125, 250 and 500 mg/kg bwt) by evaluating various biochemical parameters. The levels of blood glucose, carbohydrate metabolizing enzymes, TBARS, enzymatic and non-enzymatic antioxidants and lipid profiles were found to be significantly increased in diabetic rats when compared to control groups. Administration of extract in the treated groups showed altered changes in the above mentioned parameters and found that among the three doseses, 250 mg/kg showed best result when compared to other two doses. HRSEt possess antioxidant, hypoglycemic and hypolipidemic activity against streptozotocin induced diabetic rats. However the detailed mechanism(s) of action will require elucidating in further studies.

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ANTI-DIABETIC EFFECT OF A NOVEL NANO POLYMER OF THYMOL IN STREPTOZOTOCIN-INDUCED DIABETIC WISTAR RATS

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2019v11i5.34205 ◽

2019 ◽

pp. 81-89

Author(s):

ELAHE KARIMI ◽

SHAHRYAR ABBASI ◽

ALI AIDY ◽

HORI GHANEIALVAR ◽

SHAHRAM MOHAMMADPOUR ◽

...

Keyword(s):

Animal Model ◽

Biochemical Parameters ◽

Wistar Rats ◽

Liver Enzymes ◽

Serum Glucose ◽

Diabetic Rats ◽

Dependent Manner ◽

Elisa Kit ◽

Blood Biochemical ◽

Dose Dependent

Objective: The aim of this study was to evaluate the effect of thymol and thymol nano polymer on the blood biochemical parameters and anti-diabetic activity in Streptozotocin (STZ)-induced diabetic rats. Methods: The synthesized nano polymer (NP) was characterized by using different spectroscopy methods, such as IR, HNMR and CNMR. Loading and releasing of thymol were investigated by HPLC. Eleven groups of the Streptozotocin-induced diabetic and normal rats (overall 110 males) were tested through various biochemical factors such as: serum glucose, insulin, liver function-related enzymes including ALT, AST, ALP and bilirubin by ELISA kit methods. Results: It has shown that thymol nano polymer is desirable for transferring drug. The amount of thymol loaded on NP estimated at 43±2.5 %. Then, 65% of the loaded drug was released. LD50 for thymol and thymol nano polymer were 435 and 583 mg/kg, respectively. thymol nano polymer at doses of 30, 60 and 90 mg/kg, in a dose-dependent manner, reduced blood glucose, increased insulin levels, and controlled liver enzymes ALT, AST, ALP and bilirubin in the STZ-induced diabetic rats. Conclusion: The use of thymol nano polymer appears to be a new aspect concerning to protect diabetes-induced damage in the animal model.

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