Exercise is vital for diabetics to improve their blood glucose level. However, the quantitative relationship between exercise modes (including types, intensity, time, etc.) and the blood glucose is still not clear. In order to answer these questions, this paper established a blood glucose metabolic model based on ordinary differential equation method. Furthermore, a silico method was adopted to study the effects of different aerobic exercise intensities (light, moderate and vigorous) on blood glucose and optimal strategies of insulin infusion for type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). Additionally, the universality of proposed model and insulin infusion strategies was verified based on 1 000 virtual diabetes patients' simulation. The experimental results showed that: (1) Vigorous-intensity aerobic exercise may result in hypoglycemia (< 3.89 mmol/L), which was so harmful to health that diabetics should avoid. Compared with moderate-intensity exercise, the light-intensity aerobic exercise intuitively lowered blood glucose slowly and caused a relative long high-blood-glucose (> 6.11 mmol/L) period, however, its overall blood glucose risk index (BGRI) was lower. (2) Insulin dosage of the optimized strategies decreased by 50% and 84% for T1DM and T2DM when they did moderate intensity exercise. As for light intensity exercise, the dosage of insulin was almost the same as they didn't do exercise, but BGRI decreased significantly. (3) The simulations of 1 000 virtual diabetic patients manifested that the proposed model and the insulin infusion strategies had good universality. The results of this study can not only help to improve the quantitative understanding about the effects of aerobic exercise on blood glucose of diabetic patients, but also contribute to the regulation and management of blood glucose in exercise mode.
Blood Glucose ; metabolism ; Computer Simulation ; Diabetes Mellitus, Type 1 ; drug therapy ; metabolism ; Diabetes Mellitus, Type 2 ; drug therapy ; metabolism ; Exercise ; Humans ; Insulin ; administration & dosage ; Models, Theoretical

Acarbose is widely used as α-glucosidase inhibitor in the treatment of type Ⅱ diabetes. Actinoplanes sp. is used for industrial production of acarbose. As a secondary metabolite, the biosynthesis of acarbose is quite complex. In addition to acarbose, a few acarbose structural analogs are also accumulated in the culture broth of Actinoplanes sp., which are hard to remove. Due to lack of systemic understanding of the biosynthesis and regulation mechanisms of acarbose and its structural analogs, it is difficult to eliminate or reduce the biosynthesis of the structural analogs. Recently, the advances in omics technologies and molecular biology have facilitated the investigations of biosynthesis and regulatory mechanisms of acarbose and its structural analogs in Actinoplanes sp.. The genes involved in the biosynthesis of acarbose and its structural analogs and their regulatory mechanism have been extensively explored by using bioinformatics analysis, genetic manipulation and enzymatic characterization, which is summarized in this review.
Acarbose/metabolism* ; Diabetes Mellitus, Type 2/drug therapy* ; Genetic Techniques ; Humans

OBJECTIVETo study effects of insulin treatment on intracellular lipid content in livers and insulin resistance of type 2 diabetic rats.

METHODSType 2 diabetic rats were induced by injecting streptozotocin (25 mg/kg) and fat rich food. Then according to the results of the oral glucose tolerance test (OGTT) and glucose-induced insulin secretion test (IST), the rats were divided into two groups: control group (DC) and insulin treated group (DI). Normal rats (NC) served as controls. The treatment of each group with either NPH insulin (4 approximately 6 U . kg-1. d-1), or saline continued for 4 weeks. Body weight, OGTT, IST, blood lipids, intracellular lipids in liver and liver histology were studied. The insulin sensitivity index (ISI) was applied to assess the status of insulin resistance.

RESULTSBlood lipid and intracellular lipids in livers in the DC were higher than those in NC (t = 2.59 approximately 15.77, P < 0.05) and the ISI was lower (t = 3.16, P < 0.05), with many fatty droplets appearing in the livers. In comparison to DC, DI showed that blood lipids were decreased, but lipids in livers were markedly increased (TG, TC, FFA increased 55.7%, 19.87%, 22.2%, respectively), and fatty droplets in hepatocytes were larger, but the ISI did not change significantly.

CONCLUSIONInsulin treatment can make blood glucose normal, increase the intracellular lipid content in the liver, and not increase the insulin resistance significantly.

Animals ; Diabetes Mellitus, Experimental ; drug therapy ; metabolism ; Diabetes Mellitus, Type 2 ; drug therapy ; metabolism ; Insulin ; therapeutic use ; Insulin Resistance ; Lipid Metabolism ; Liver ; metabolism ; Male ; Rats ; Rats, Wistar

Diabetic nephropathy (DN) is one of the most common complications of diabetes mellitus, which is characterized in renal tubulointerstitial fibrosis (TIF). The current study was designed to investigate the protective effect of Jujuboside A (Ju A) on TIF in type 2 diabetes (T2DM) mice, and explore its underlying anti-fibrosis mechanism. A mouse T2DM model was established using high fat diet (HFD) feeding combined with intraperitoneal injection of streptozotocin (STZ). Then, diabetic mice were treated with Ju A (10, 20 and 40 mg·kg^-1·d^-1, i.g.) for 12 weeks. Results showed that administration of Ju A not only down-regulated fasting blood glucose (FBG) levels, but also improved hyperlipidemia and renal function in diabetic mice. Moreover, the reduced ECM accumulation was observed in the renal cortex of Ju A treated diabetic mice, while the TIF progression was also attenuated by Ju A through blocking the epithelial-to-mesenchymal transition (EMT) of renal tubular epithelial cells (RTECs). Further mechanism studies showed that Ju A treatment effectively down-regulated the protein expression and subsequent nuclear translocation of Yin Yang 1 (YY1) in the renal cortex of diabetic mice, and reduced the levels of transforming growth factor-β1 (TGF-β1) in the serum and renal cortex of Ju A treated mice. According to invitro studies, the up-regulated YY1/TGF-β1 signaling pathway was restored by Ju A in high glucose (HG) cultured HK-2 cells. Taken together, these findings demonstrated that Ju A can ameliorate the TIF of DN through down-regulating the YY1/TGF-β1 signaling pathway.
Animals ; Blood Glucose ; Diabetes Mellitus, Experimental/metabolism* ; Diabetes Mellitus, Type 2/drug therapy* ; Diabetic Nephropathies/metabolism* ; Fibrosis ; Mice ; Saponins ; Signal Transduction ; Streptozocin ; Transforming Growth Factor beta1/metabolism*

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce cardiovascular mortality in patients with diabetes mellitus but the protective mechanism remains elusive. Here we demonstrated that the SGLT2 inhibitor, Empagliflozin (EMPA), suppresses cardiomyocytes autosis (autophagic cell death) to confer cardioprotective effects. Using myocardial infarction (MI) mouse models with and without diabetes mellitus, EMPA treatment significantly reduced infarct size, and myocardial fibrosis, thereby leading to improved cardiac function and survival. In the context of ischemia and nutritional glucose deprivation where autosis is already highly stimulated, EMPA directly inhibits the activity of the Na⁺/H⁺ exchanger 1 (NHE1) in the cardiomyocytes to regulate excessive autophagy. Knockdown of NHE1 significantly rescued glucose deprivation-induced autosis. In contrast, overexpression of NHE1 aggravated the cardiomyocytes death in response to starvation, which was effectively rescued by EMPA treatment. Furthermore, in vitro and in vivo analysis of NHE1 and Beclin 1 knockout mice validated that EMPA's cardioprotective effects are at least in part through downregulation of autophagic flux. These findings provide new insights for drug development, specifically targeting NHE1 and autosis for ventricular remodeling and heart failure after MI in both diabetic and non-diabetic patients.
Animals ; Diabetes Mellitus ; Diabetes Mellitus, Type 2/drug therapy* ; Glucose ; Humans ; Mice ; Myocardial Infarction/metabolism* ; Sodium-Glucose Transporter 2 Inhibitors/therapeutic use* ; Ventricular Remodeling

Berberine (BBR) is a type of alkaloids isolated from Coptidis Rhizoma and Phellodendri Chinensis Cortex and has been used to treat bacterial gastroenteritis, diarrhea and other digestive diseases for more than 1 000 years. According to recent studies, berberine has been found to have multiple pharmacological activities, including lowering blood glucose and lipid, anti-inflammation, antioxidation, relieving type 2 diabetic nephropathy (DN), diabetic cardiovascular disease, diabetic peripheral neuropathy ( DPN) and other complications. In this article, the authors summarized the literature reports about the effects of BBR in lowering blood glucose and preventing and treating the above type 2 diabetes and its complications, in order to provide reference to further studies and promotion of BBR's application.
Animals ; Berberine ; administration & dosage ; Blood Glucose ; metabolism ; Diabetes Complications ; drug therapy ; metabolism ; Diabetes Mellitus, Type 2 ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; Humans

This study focused on the ameliorative effects of gypenosides(GPS) on insulin sensitivity and inflammatory factors in rats with type 2 diabetes mellitus(T2 DM) and explored their possible molecular mechanisms. After the successful establishment of T2 DM model, diabetic rats were randomly divided into four groups, including model group, GPS groups(200, 100 mg·kg~(-1)) and metformin group(100 mg·kg~(-1)), with healthy rats serving as the control. After 6-week intragastric administration, fasting blood glucose(FBG) and oral glucose tolerance were examined. The levels of insulin, C-peptide, tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6) and C-reactive protein(CRP) in serum were examined. Then the homeostasis model assessment of insulin resistance(HOMA-IR) and insulin sensitivity index(ISI) were calculated. The protein expression levels of phosphorylated insulin receptor substrate-1(p-IRS-1) and phosphorylated protein kinase B(p-Akt) in skeletal muscle were measured by Western blot, as well as those of phosphorylated inhibitor of nuclear factor-κB(NF-κB) kinase β(p-IKKβ), phosphorylated alpha inhibitor of NF-κB(p-IκBα) and phosphorylated p65 subunit of NF-κB(p-p65) in adipose tissue. The relative expression levels of glucose transporter 4(GLUT4) mRNA in skeletal muscle and NF-κB mRNA in adipose tissue were measured by qRT-PCR, and the morphological changes of pancreatic tissue were observed. Compared with the model group, the GPS groups witnessed significant decrease in FBG, marked amelioration of impaired oral glucose tolerance and significant increase in ISI. Further, the high-dose GPS group saw significantly reduced HOMA-IR, TNF-α, IL-1β and CRP, significantly increased expression levels of p-IRS-1(Tyr), p-Akt and GLUT4, and markedly inhibited p-IRS-1(Ser), p-IKKβ, p-IκBα, p-p65 and NF-κB. The concentration of CRP and the expression levels of p-IRS-1(Ser), p-IKKβ, p-IκBα and NF-κB were remarkably reduced in the low-dose GPS group. However, GPS was found less effective in the regulation of serum insulin, C-peptide and IL-6 levels and the alleviation of pancreatic islet injury. The results indicated that GPS can reduce FBG and improve insulin sensitivity in diabetic rats possibly by regulating the NF-κB signaling pathway, inhibiting inflammation, and thereby regulating the expression of key proteins in the insulin signaling pathway.
Animals ; Diabetes Mellitus, Experimental/drug therapy* ; Diabetes Mellitus, Type 2/genetics* ; Gynostemma ; Insulin ; Insulin Resistance ; NF-kappa B/metabolism* ; Plant Extracts ; Rats ; Signal Transduction

OBJECTIVETo observe the effects of Ganoderma lucidum spores on Cytochrome C (Cyt-C) and mitochondrial calcium in the testis of NIDDM rats.

METHODSFifty male Wistar rats were divided randomly into three groups: model, ganoderma and normal control, the first two groups injected with 2% STZ through vena caudalis, and the last one with half-and-half sodium citrate/citrate buffer solution. Two weeks after normal diet, glucose tolerance tests were performed and the rats with abnormal glucose tolerance from the model and ganoderma groups received high-fat and high-carbohydrate food, the ganoderma group given Ganoderma lucidum spores (250mg/[ kg x d] ) in addition, both for 10 weeks. Glucose tolerance tests were repeated 1 day before the end of the experiment and the rats were castrated and relevant indexes measured.

RESULTSThe NIDDM model was successfully constructed. In the model group, the levels of mitochondrial Cyt-C and mitochondrial calcium were significantly lower (P <0. 05) while that of the plasma Cyt-C was significantly higher than in the ganoderma and the control groups.

CONCLUSIONCyt-C and calcium ion are involved in the damage of the testis. Ganoderma lucidum spores can protect the testis of NIDDM rats.

Animals ; Calcium ; metabolism ; Cytochromes c ; metabolism ; Diabetes Mellitus, Experimental ; drug therapy ; Diabetes Mellitus, Type 2 ; drug therapy ; Male ; Mitochondria ; drug effects ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Reishi ; Testis ; drug effects ; metabolism

OBJECTIVETo evaluate islet beta cell response to intravenous glucagon (a non-glucose secretagogue) stimulation in diabetes mellitus.

METHODSNineteen patients with type 1 diabetes (T1D) and 131 patients with type 2 diabetes (T2D) were recruited in this study. T2D patients were divided into two groups according to therapy: 36 cases treated with insulin and 95 cases treated with diet or oral therapy. The serum C-peptide levels were determined at fasting and six minutes after intravenous injection of 1 mg of glucagon.

RESULTSBoth fasting and 6-minute post-glucagon-stimulated C-peptide levels in T1D patients were significantly lower than those of T2D patients (0.76 +/- 0.36 ng/mL vs. 1.81 +/- 0.78 ng/mL, P < 0.05; 0.88 +/- 0.42 ng/mL vs. 3.68 +/- 0.98 ng/mL, P < 0.05). In T1D patients, the C-peptide level after injection of glucagon was similar to the fasting level. In T2D, patients treated with diet or oral drug had a significantly greater fasting and stimulated C-peptide level than those patients received insulin therapy (2.45 +/- 0.93 ng/mL vs. 1.61 +/- 0.68 ng/mL, P < 0.05; 5.26 +/- 1.24 ng/mL vs. 2.15 +/- 0.76 ng/mL, P < 0.05). The serum C-peptide level after glucagon stimulation was positively correlated with C-peptide levels at fasting in all three groups (r = 0.76, P < 0.05).

CONCLUSIONSThe 6-minute glucagon test is valuable in assessing the function of islet beta cell in patients with diabetes mellitus. It is helpful for diagnosis and treatment of diabetes mellitus.

Adult ; C-Peptide ; blood ; Diabetes Mellitus, Type 1 ; drug therapy ; Diabetes Mellitus, Type 2 ; drug therapy ; Female ; Glucagon ; pharmacology ; therapeutic use ; Glycated Hemoglobin A ; metabolism ; Humans ; Insulin ; therapeutic use ; Islets of Langerhans ; drug effects ; metabolism ; Male ; Middle Aged

OBJECTIVETo investigate the changes of xanthine oxidase (XOD), myeloperoxidase (MPO) and mitochondrial succinate dehydrogenase (SDH) in the testis and the protective effect of ganoderma lucidum spores on the testicular tissue of rats with non-insu- lin-dependent diabetes mellitus (NIDDM).

METHODSFifty male Wistar rats were divided randomly into a model, a ganoderma and a normal control group, the first two groups injected with 2% STZ (25 mg/kg) through the peritoneum, and the last one with half-and-half sodium citrate/citrate buffer solution. Two weeks after normal diet, glucose tolerance tests were performed and the rats with abnormal glucose tolerance in the model and ganoderma groups received high-fat and high-carbohydrate food, the latter given ganoderma lycium spores (250 mg/kg x d) in addition, both for 10 weeks and all rats fed alone. Glucose tolerance tests were repeated 1 day before the end of the experiment and the testes of the rats were harvested for the determination of XOD, MPO and SDH.

RESULTSSDH was significantly lower (P < 0.05) while XOD and MPO significantly higher in the model group than in the ganoderma and control groups (P < 0.05). The model rats exhibited abnormal convoluted seminiferous tubules, indistinct parietal layers, decreased or abolished gonepoiesis, luminal peripheral fibrous tissue (interstitial substance) accrementition, basal lamina thickening, and vessel wall fibrous tissue accrementition and sclerosis.

CONCLUSIONGanoderma lucidum spores can protect the testis of diabetic rats by reducing free radical-induced damage to the testicular tissue and enhancing the activity of SDH.

Animals ; Diabetes Mellitus, Experimental ; drug therapy ; metabolism ; Diabetes Mellitus, Type 2 ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; therapeutic use ; Male ; Peroxidase ; metabolism ; Rats ; Rats, Wistar ; Reishi ; Spores, Fungal ; Succinate Dehydrogenase ; metabolism ; Testis ; metabolism ; Xanthine Oxidase ; metabolism