Effects of three Huanglian-derived polysaccharides on the gut microbiome and fecal metabolome of high-fat diet/streptozocin-induced type 2 diabetes mice.

Plant-derived polysaccharides are important components for biological functions. The objective of this study is to study the mechanisms by which polysaccharides from three Huanglian (Rhizome Coptidis, HL) of Coptis chinensis, C. deltoidea, and Coptis teeta affect type 2 diabetes mellitus (T2DM) by analyzing the gut microbiome and their metabolites. A long-term high-fat diet (HFD) combined with streptozocin (STZ) induction was used to construct the T2DM mice model. The histopathology of liver, pancreas, and colon, biochemical indexes related to mice were determined to assess the ameliorative effects of these three HL polysaccharides (HLPs) on T2DM. The results indicated that oral HLPs improved hyperglycemia, insulin resistance, blood lipid levels, and ß-cell function. Further, HLPs elevated the growth of advantageous beneficial bacteria within the gut microbiota and raised the concentrations of short-chain fatty acids (SCFAs), particularly butyric acid. Metabolic analyses showed that HLPs ameliorated the effects of T2DM on microbial-derived metabolites and related metabolic pathways, especially the biosynthetic pathways of phenylalanine, tyrosine, and tryptophan. In the combined analysis, many associations of T2DM-related biochemical indicators with gut microbes and their metabolites were extracted, which suggested the important role of gut microbiome and fecal metabolome in the amelioration of type 2 diabetes mellitus by HLPs.

Carboxymethyl chitosan-TK resistant starch complex ameliorates type 2 diabetes by regulating the gut microbiota.

Carboxymethyl chitosan and resistant starch exhibit good performance in diabetes regulation. We prepared carboxymethyl chitosan - resistant starch complex. Test the properties of composite resistant starch by using X-ray diffraction, water contact angle, infrared spectroscopy, and scanning electron microscopy, interactions with intestinal microbiota and mouse experiments were also conducted. The results indicated that the composite resistant starch had a good effect on promoting the proliferation of probiotics on Bifidobacterium and a significant inhibitory effect on Escherichia coli than resistant starch (P < 0.05). After administration, the water intake and weight of diabetic mice were significantly reduced. The blood glucose of diabetic mice was also reduced, and oral glucose tolerance showed that the glucose degradation rates of composite resistant starch were significantly improved compared to model mice. Cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein were significantly lower than those in the diabetes group (P < 0.05). The diversity of the gut microbiota was also proven.

In Vitro and In Vivo Antidiabetic Activity, Phenolic Content and Microscopical Characterization of Terfezia claveryi.

Terfezia claveryi (T. claveryi) is used by traditional healers in the Middle East region to treat several diseases, including diabetes. The present study evaluated the total phenolic and investigated the blood-glucose-lowering potential of different aqueous extracts of this selected truffle using in vitro and in vivo models. The phytochemical profile was examined using UPLC-MS. The macerate and the microwave-assisted extract were the richest in phenolic compounds. All T. claveryi extracts exhibited a remarkable α-glucosidase inhibitory effect in vitro, with an IC50 of 2.43, 3.26, 5.18 and 3.31 mg/mL for the aqueous microwave-assisted extract macerate, infusion and decoction, respectively. On the other hand, in the high-fat diet alloxan-induced diabetic mice model, all tested crude aqueous extracts exhibited a significant antihyperglycemic activity (p < 0.05). Four hours after the administration of the 250 mg/kg dose, the macerate was able to induce a 29.4% blood-glucose-lowering effect compared to a 24.8% reduction induced by the infusion, which was sustained for a further two hours. The hypoglycemic effect (29.3% and 32.4%) was also recorded six hours after the administration of the single dose 500 mg/kg of the macerate and the infusion, respectively. Truffle extracts exhibited antidiabetic activity both in vitro and in vivo, providing a rationale for the traditional use as a natural hypoglycemic.

The renal protective effect of saxagliptin combined with metformin on type 2 diabetic mice and its relationship with redox balance / 中国药理学通报

Aim To evaluate the reno-proteetion of saxagliptin combined with metformin in mice with T2DM anrl its relationship with redox balance.Meth¬ods C57BL/6J mice were fed with high fat diet and injected with low dose STZ intraperitoneally to establish T2DM mouse model.Then they were randomly divided into T2DM group, glibenclamide group ( Gli group), metformin group ( Met group) , saxagliptin group ( Sax group) and saxagliptin + metformin group ( S + M group) , and normal control group ( NC group) with 8 mice in each group.Eight weeks after intervention the mice were weighed.Blood, urine and renal tissue sam¬ples were collected to measure GHbA,c, FBG, Alb, 8-OHdG, 8-iso-PG, SOD, GSH, GSSG and Ucr.The pathological morphology of renal tissues in each group was observed.Results Saxagliptin combined with metformin reduced significantly the levels of Alb/Ucr ( UACR) , 8-0HdG/Ucr( UOCR) , 8-iso-PG/Ucr( UP- CR) , increased the activity of SOD and GSH/GSSG ratio, and improved the pathological changes of renal tissues, which were superior to those in Met group and Sax group.Conclusions Saxagliptin combined with metformin have a synergistic protective effect on the kidneys of type 2 diabetic mice.The mechanism is partly related to alleviating oxidative stress and impro¬ving redox balance in vivo.

Combination treatment strategies with a focus on rosiglitazone and adriamycin for insulin resistant liver cancer.

Insulin resistance promotes the occurrence of liver cancer and decreases its chemosensitivity. Rosiglitazone (ROSI), a thiazolidinedione insulin sensitiser, could be used for diabetes with insulin resistance and has been reported to show anticancer effects on human malignant cells. In this paper, we investigated the combination of ROSI and chemotherapeutics on the growth and metastasis of insulin-resistant hepatoma. In vitro assay, ROSI significantly enhanced the inhibitory effects of adriamycin (ADR) on the proliferation, autophagy and migration of insulin-resistant hepatoma HepG2/IR cells via downregulation of EGFR/ERK and AKT/mTOR signalling pathway. In addition, ROSI promoted the apoptosis of HepG2/IR cells induced by ADR. In vivo assay, high fat and glucose diet and streptozotocin (STZ) induced insulin resistance in mice by increasing the body weight, fasting blood glucose (FBG) level, oral glucose tolerance, fasting insulin level and insulin resistance index. Both the growth of mouse liver cancer hepatoma H22 cells and serum FBG level in insulin resistant mice were significantly inhibited by combination of ROSI and ADR. Thus, ROSI and ADR in combination showed a stronger anti-tumour effect in insulin resistant hepatoma cells accompanying with glucose reduction and might represent an effective therapeutic strategy for liver cancer accompanied with insulin resistant diabetes.

Long-term treatment of polysaccharides-based hydrogel microparticles as oral insulin delivery in streptozotocin-induced type 2 diabetic mice.

To develop a more effective and safer drug for the treatment of type 2 diabetes mellitus (T2DM), polysaccharides-based hydrogel microparticles as oral insulin delivery was prepared and explored. This study was aimed to evaluate the antidiabetic effects and hypoglycemic mechanism with long-term administration(four weeks) of oral insulin hydrogel microparticles in type 2 diabetic mice on a model of diabetes using a high fat diet combined with streptozotocin. The results revealed that the long-term treatment of oral insulin polysaccharides-based hydrogel microparticles could significantly alleviate the symptoms of polyphagia, polydipsia, polyuria and weight loss in diabetic mice. Also, oral administration of insulin hydrogel microparticles could significantly reduce fasting blood glucose levels, ameliorate insulin resistance and increase insulin sensitivity in the mice with T2DM. The concentration of plasma TG, TC, LDL-C, FFA, BUN, CRE significantly decreased and the levels of HDL-C increased showed that insulin polysaccharides-based hydrogel microparticles were effective in regulating lipid metabolism and prevent diabetic nephropathy complication in diabetic mice. In addition, the supplementation of insulin hydrogel microparticles could significant improve the antioxidant capacity by increasing the level of SOD, CAT and decreasing the level of MDA, GPT, NO, TNF-α, and reverse histological deterioration of kidney and pancreas in diabetic mice. The above outcome concluded that insulin polysaccharides-based hydrogel microparticles may exhibit promising anti-diabetic activity and the potential to be a drug candidate for T2DM.

Augmented Brain Infiltration and Activation of Leukocytes After Cerebral Ischemia in Type 2 Diabetic Mice.

Background: Stroke patients with diabetes suffer from higher mortality rate and worsened neurological outcome. However, the responses of immune system to cerebral ischemia in the setting of diabetes remain poorly understood. Methods: In this study, we investigated the temporal profile of leukocyte mobilization and brain infiltration following distal middle cerebral artery occlusion (dMCAO) in db/db mouse model of type 2 diabetes (T2D) and its db/+ normoglycemic controls. Results: We found a significant increase of brain-infiltrating CD4+ T cell at day 3 after dMCAO, and a delayed and dramatic increase of brain-infiltrating neutrophils, CD4+ T cells, CD8+ T cells, and B cells at day 7 after dMCAO in db/db mice vs. db/+ controls. Leukocyte subsets in the circulation and spleen were also measured, however, there is no significant difference between non-diabetic and diabetic groups. Furthermore, we identified an increased expression of activation marker CD69 in brain-infiltrating neutrophils, CD4+ T and CD8+ T cells, and IFN-γ in brain-infiltrating CD4+ T cells in db/db mice at day 7 after dMCAO. Conclusions: These findings for the first time demonstrate that cerebral ischemia induces a delayed and sustained augmentation of brain infiltration and activation of neutrophils and lymphocytes in type 2 diabetic mice and these altered immune responses might contribute to the severer brain tissue damage and worse neurological outcomes of diabetes stroke, which warrants further investigation.

Alterations of morphology and phosphorylated protein expression in the seminal vesicles of diabetic mice.

Although many studies reported the detrimental effects of type 1 and 2 diabetes mellitus (T1DM and T2DM) on testis, reproductive parameter changes in DM seminal vesicles have never been documented. This study aimed to examine the morphology, biochemical levels and tyrosine phosphorylation in seminal vesicles of T1DM and T2DM mice. Fifty-six male C57BL/6 mice were divided into four groups (n = 14/each): T1DM control, T1DM, T2DM control and T2DM. T1DM mice were daily injected of streptozotocin (STZ; 40 mg/kg BW) for 5 days. T2DM mice received high-fat diet for 14 days prior to STZ injection at a single dose (85 mg/kg BW). At the end of experiments (days 36 and 72), magnesium (MG) and fructosamine (FRA) levels, and phosphorylated protein expression in seminal vesicle were examined. The results showed that seminal and prostate weights and MG and FRA levels of T1DM animals were significantly increased as compared to T2DM mice. Some seminal histopathologies and decreased epithelial height were observed in both DM groups. Significantly, a 72-kDa phosphorylated protein expression was increased in DM seminal vesicle. We concluded that changes of biochemical components and phosphorylated proteins in seminal vesicle of T1DM and T2DM mice may be associated with low-quality seminal plasma.

Characteristics of bone strength and metabolism in type 2 diabetic model Tsumura, Suzuki, Obese Diabetes mice.

OBJECTIVE: Type 2 diabetes mellitus (T2DM) is a metabolic disease characterized by hyperglycemia, hyperinsulinemia, and complications such as obesity and osteoporosis. The Tsumura, Suzuki, Obese Diabetes (TSOD) mouse is an animal model of spontaneous obese T2DM. However, bone metabolism in TSOD mice is yet to be investigated. The objective of the present study was to investigate the effects of T2DM on bone mass, metabolism, microstructure, and strength in TSOD mice. METHODS: We determined the following parameters in TSOD mice and Tsumura, Suzuki, Non-obesity (TSNO) mice (as controls): serum glucose levels; serum insulin levels; bone mass; bone microstructure; bone metabolic markers; and bone strength. We also performed the oral glucose tolerance test and examined histological sections of the femur. We compared these data between both groups at pre-diabetic (10 weeks) and established (20 weeks) diabetic conditions. RESULTS: Bone strength, such as extrinsic mechanical properties, increased with age in the TSOD mice and intrinsic material properties decreased at both 10 weeks and 20 weeks. Bone resorption marker levels in TSOD mice were significantly higher than those in the control mice at both ages, but there was no significant difference in bone formation markers between the groups. Bone mass in TSOD mice was lower than that in controls at both ages. The trabecular bone volume at the femoral greater trochanter increased with age in the TSOD mice. The femoral mid-diaphysis in TSOD mice was more slender and thicker than that in TSNO mice at both ages. CONCLUSIONS: Bone mass of the femur was lower in TSOD mice than in TSNO mice because hyperinsulinemia during pre-diabetic and established diabetic conditions enhanced bone resorption due to high bone turnover. In addition, our data suggest that the bone mass of the femur was significantly reduced as a result of chronic hyperglycemia during established diabetic conditions in TSOD mice. We suggest that bone strength in the femur deteriorated due to the reduction of bone mass and because the femoral mid-diaphysis was more slender in TSOD mice.

Antigen Loading (e.g., Glutamic Acid Decarboxylase 65) of Tolerogenic DCs (tolDCs) Reduces Their Capacity to Prevent Diabetes in the Non-Obese Diabetes (NOD)-Severe Combined Immunodeficiency Model of Adoptive Cotransfer of Diabetes As Well As in NOD Mice.

Tolerogenic DCs (tolDCs) are being researched as a promising intervention strategy also in autoimmune diseases including type 1 diabetes (T1D). T1D is a T-cell-mediated, organ-specific disease with several well-defined and rather specific autoantigens, i.e., proinsulin, insulin, glutamic acid decarboxylase 65 (GAD65), that have been used in animal as well as human intervention trials in attempts to achieve a more efficient, specific immunotherapy. In this study, we have tested tolerogenic DCs for their effectiveness to prevent adoptive transfer of diabetes by diabetogenic splenocytes into non-obese diabetes (NOD)-severe combined immunodeficiency (NOD-SCID) recipients. While i.p. application of tolDCs prepared from bone marrow of prediabetic NOD mice by vitamin D2 and dexamethasone significantly reduced diabetes transfer into the NOD-SCID females, this effect was completely abolished when tolDCs were loaded with the mouse recombinant GAD65, but also with a control protein-ovalbumin (OVA). The effect was not dependent on the presence of serum in the tolDC culture. Similar results were observed in NOD mice. Removal of possible bystander antigen-presenting cells within the diabetogenic splenocytes by negative magnetic sorting of T cells did not alter this surprising effect. Tolerogenic DCs loaded with an immunodominant mouse GAD65 peptide also displayed diminished diabetes-preventive effect. Tolerogenic DCs were characterized by surface maturation markers (CD40, CD80, CD86, MHC II) and the lipopolysaccharide stability test. Data from alloreactive T cell proliferation and cytokine induction assays (IFN-γ) did not reveal the differences observed in the diabetes incidence. Migration of tolDCs, tolDCs-GAD65 and tolDCs-OVA to spleen, mesenteric- and pancreatic lymph nodes displayed similar, mucosal pattern with highest accumulation in pancreatic lymph nodes present up to 9 days after the i.p. APPLICATION: These data document that mechanisms by which tolDCs operate in vivo require much better understanding for improving efficacy of this promising cell therapy, especially in the presence of an antigen, e.g., GAD65.

Dapper1 attenuates hepatic gluconeogenesis and lipogenesis by activating PI3K/Akt signaling.

Studies have shown that hepatic insulin resistance, a disorder of glucose and lipid metabolism, plays a vital role in type 2 diabetes (T2D). To clarify the function of Dapper1 in glucose and lipid metabolism in the liver, we investigated the relationships between Dapper1 and adenosine triphosphate (ATP)- and Ca2+-mediated activation of PI3K/Akt. We observed a reduction in hepatic Dapper1 in db/db (mice that are homozygous for a spontaneous diabetes mutation) and HFD-induced diabetic mice with T2D. Hepatic overexpression of Dapper1 improved hyperglycemia, insulin resistance, and fatty liver. It also increased Akt (pAkt) signaling and repressed both gluconeogenesis and lipogenesis. Conversely, Ad-shDapper1-induced knockdown of hepatic Dapper1 promoted gluconeogenesis and lipogenesis. Furthermore, Dapper1 activated PI3K p110α/Akt in an insulin-independent manner by inducing ATP production and secretion in vitro. Blockade of P2 ATP receptors, the downstream phospholipase C (PLC), or the inositol triphosphate receptor (IP3R all reduced the Dapper1-induced increase in cytosolic free calcium and Dapper1-mediated PI3K/Akt activation, as did removal of calcium in the medium. In conclusion, Dapper1 attenuates hepatic gluconeogenesis and lipogenesis in T2D.

Effects of Uygur Medicine Branchlets roses extracts on blood glucose and glucose tolerance in diabetes mice induced by alloxan / 药物评价研究

Objective To observe the effect of extract from Branchlets roses on blood glucose and glucose tolerance in diabetes mice induced by alloxan.Methods Diabetes animal model was established by alloxan.Dividing the model mice into eight groups:model group,water extract high,middle,and low dose (3.70,1.85,and 0.93 g/kg) group,and ethanol extract high,middle,and low dose (2.75,1.37,and 0.70 g/kg) group,and metformin (positive drug,200 mg/kg) group,and normal mice were taken as control group.Drug was ig administered to mice 3 d after molding once daily.Blood glucose test paper was used to determine fasting blood glucose 0,10,20,and 28 d after modeling,and the glucose tolerance test was performed 30 d after modeling.Results The extract of Branchlets roses from all the groups could decrease the blood glucose and improve the glucose tolerance,and showed a certain dose-effect relationship.In all the extracts,the alcohol extract had the best effect,but the effect was not as good as the positive control drug metformin hydrochloride group.Conclusion The extract of Branchlets roses can reduce the blood sugar content of diabetic mice,and improve the glucose tolerance.

Comparison of wound healing in two mouse models of type 2 diabetes / 中国比较医学杂志

Objective To compare the characteristics of ulcer wound healing in current commonly used C57BL/6J-db/db mouse models of spontaneous gene mutation-induced type 2 diabetes and in C57BL/6J mice with diabetes induced by streptozotocin (STZ), and to provide a basis for related experimental studies on diabetic ulcer in animal models.Methods To establish the mouse models of diabetic ulcer wound, observe the healing time and calculate the wound healing rate at 0, 3, 5, 7, 10, 14 days.Tissue samples were collected at days 7 and 14.HE and Masson staining, and immunohistochemistry (CD31 and PCNA) were used to observe the pathological changes of the wound tissues.Gene expressions of collagen-IIIα, fibronectin and α-SMA were detected by fluorescent quantitative analysis.Results The wound healing time of db/db mice was significantly delayed compared with the STZ mice, which was extended from 16.6±0.8 d to 20.2±1.3 d (P< 0.001).Compared with the STZ group, the growth of granulation tissue in the db/db group was slow, the length of newly formed epithelium was insufficient, the collagen deposition was disordered, and the wound healing was poor.At 7 days, the expression of CD31 and PCNA was significantly lower in the db/db group (P< 0.01), and at 7 and 14 days, the increase of collagen-IIIα and α-SMA genes up-regulation was significantly lower in the db/db group than in the STZ group.Conclusions Both the two types of diabetic mice show delayed wound healing.However, compared with the STZ-induced diabetic mice, the gene mutation db/db mice are more suitable for studies of diabetic ulcer wound healing as regarding the extent of the delay and the degree of difficulty of wound healing.

Study on Glycolipid Metablism of Mice with Diabetes Induced by Peptide Receptor Antagonist Pro3(GIP) / 现代检验医学杂志

Objective To investigate the metabolic effects of glucose dependent insulinotropic peptide receptor antagomst pro3 (GIP) in induced diabetes mice about blood glucose,triglyceride,cholesterol,leptin and fatty issue.Methods 27 C57 mice were randomly divided into normal group and diabetes mice group,and the mice in diabetes group were fed with high fat food and intraperitoneal injected streptozocin.Then 1 mouse that random blood giucose lower than 16.9 mmol/L was deleted in diabetes group.The rest mice in diabetes group were divided into two groups,diabetes control group,pro3 (GIP) group.Pro3 (GIP) group was given drug pro3 (GIP).The bloodglucose and glucose tolerance were measured.After treatment for 6 weeks,all mice were sacrificed and fatty tissues were collected.Results After 6 weeks,the blood glucose of the pro3 (GIP) group was obviously lower than diabetes control group (t=8.43,P＜0.01),and insulin levers in 0,30,60 and 120 min were obviously lower than diabetes control group (t =3.90,2.60,6.88 and 3.33,P＜0.05).There was significant difference between pro3 (GIP) group and diabetes control group about inflammatory cells.Moreover,leptin in pro3 (GIP) group was obviously lower than in diabetes control group (t =5.04,P＜0.01),but triglyceride,cholesterol,and adiponectin had no significant difference between two groups.Conclusion Pro3 (GIP) can significantly reduce blood glucose,insulin level,leptin of diabetes mice,and attenuate the inflammatory cells infiltration in fatty issue.

Modulation of sphingosine-1-phosphate and apolipoprotein M levels in the plasma, liver and kidneys in streptozotocin-induced diabetic mice.

AIMS/INTRODUCTION: Sphingosine-1-phosphate (S1P), a multifunctional bioactive lipid mediator, is involved in various diseases. Apolipoprotein M (ApoM) carries S1P on high-density lipoprotein and modulates S1P metabolism to increase the total S1P mass in the body. Both S1P and ApoM are involved in diabetes. MATERIALS AND METHODS: The present study examined the modulation of S1P and ApoM levels in the plasma, liver and kidneys in streptozotocin-induced diabetes (STZ) mice, and the effects of insulin on the S1P and ApoM levels in the plasma and liver in STZ mice and normal mice. We also examined the effects of insulin and glucose on the ApoM levels in HepG2 cells. RESULTS: In STZ mice, both the plasma S1P and ApoM levels were higher than those in control mice. The hepatic S1P and ApoM contents were also elevated. The hepatic S1P and ApoM contents were reduced by insulin treatment, whereas high-dose insulin decreased the plasma S1P and ApoM levels. In mice without streptozotocin treatment, the administration of insulin decreased the plasma S1P and ApoM levels, and the hepatic content of ApoM, whereas the hepatic level of S1P was not altered. Treatment with insulin and incubation under a low glucose level decreased the ApoM levels in HepG2 cells. Regarding the kidney, the renal levels of S1P and ApoM were increased in STZ mice, and insulin treatment partially restored this increment. CONCLUSIONS: In STZ mice, the levels of S1P and ApoM in the plasma, liver, and kidneys were increased. Insulin treatment somehow reversed this modulation in STZ mice.