OBJECTIVE: To explore the role of 5-hydroxytryptamine (5-HT) in type 2 diabetes mellitus (T2DM)-related hepatic inflammation and fibrosis. METHODS: Male C57BL/6J mice were used to establish T2DM model by high-fat diet feeding combined with intraperitoneal injection of streptozotocin. Then, the mice with hyperglycemia were still fed with high-fat diet for nine weeks, and treated with or without 5-HT_2A receptor (5-HT_2AR) antagonist sarpogrelate hydrochloride (SH) and 5-HT synthesis inhibitor carbidopa (CDP) (alone or in combination). To observe the role of 5-HT in the myofibroblastization of hepa-tic stellate cells (HSCs), human HSCs LX-2 were exposed to high glucose, and were treated with or without SH, CDP or monoamine oxidase A (MAO-A) inhibitor clorgiline (CGL). Hematoxylin & eosin and Masson staining were used to detect the pathological lesions of liver tissue section, immunohistochemistry and Western blot were used to analyze protein expression, biochemical indicators were measured by ELISA or enzyme kits, and levels of intracellular reactive oxygen species (ROS) were detected by fluorescent probe. RESULTS: There were up-regulated expressions of 5-HT_2AR, 5-HT synthases and MAO-A, and elevated levels of 5-HT in the liver of the T2DM mice. In addition to reduction of the hepatic 5-HT levels and MAO-A expression, treatment with SH and CDP could effectively ameliorate liver lesions in the T2DM mice, both of which could ameliorate hepatic injury and steatosis, significantly inhibit the increase of hepatic ROS (H₂O₂) levels to alleviate oxidative stress, and markedly suppress the production of transforming growth factor β1 (TGF-β1) and the development of inflammation and fibrosis in liver. More importantly, there was a synergistic effect between SH and CDP. Studies on LX-2 cells showed that high glucose could induce up-regulation of 5-HT_2AR, 5-HT synthases and MAO-A expression, increase intracellular 5-HT level, increase the production of ROS, and lead to myofibroblastization of LX-2, resulting in the increase of TGF-β1 synthesis and production of inflammatory and fibrosis factors. The effects of high glucose could be significantly inhibited by 5-HT_2AR antagonist SH or be markedly abolished by mitochondrial 5-HT degradation inhibitor CGL. In addition, SH significantly suppressed the up-regulation of 5-HT synthases and MAO-A induced by high glucose in LX-2. CONCLUSION Hyperglycemia-induced myofibroblastization and TGF-β1 production of HSCs, which leads to hepatic inflammation and fibrosis in T2DM mice, is probably due to the up-regulation of 5-HT_2AR expression and increase of 5-HT synthesis and degradation, resulting in the increase of ROS production in mitochondria. Among them, 5-HT_2AR is involved in the regulation of 5-HT synthases and MAO-A expression.
Male ; Mice ; Humans ; Animals ; Hepatic Stellate Cells/pathology* ; Transforming Growth Factor beta1/pharmacology* ; Serotonin/metabolism* ; Reactive Oxygen Species/metabolism* ; Diabetes Mellitus, Type 2/complications* ; Hydrogen Peroxide/metabolism* ; Mice, Inbred C57BL ; Liver Cirrhosis/etiology* ; Hyperglycemia/pathology* ; Monoamine Oxidase/metabolism* ; Inflammation ; Glucose/metabolism* ; Cytidine Diphosphate/pharmacology*

Sepsis, which is induced by severe bacterial infections, is a major cause of death worldwide, and therapies combating the disease are urgently needed. Because many drugs have failed in clinical trials despite their efficacy in mouse models, the development of reliable animal models of sepsis is in great demand. Several studies have suggested that rabbits reflect sepsis-related symptoms more accurately than mice. In this study, we evaluated a rabbit model of acute sepsis caused by the intravenous inoculation of Salmonella enterica. The model reproduces numerous symptoms characteristic of human sepsis including hyperlactatemia, hyperglycemia, leukopenia, hypothermia and the hyperproduction of several pro-inflammatory cytokines. Hence, it was chosen to investigate the proposed ability of Pep19-2.5—an anti-endotoxic peptide with high affinity to lipopolysaccharide and lipoprotein—to attenuate sepsis-associated pathologies in combination with an antibiotic (ceftriaxone). We demonstrate that a combination of Pep19-2.5 and ceftriaxone administered intravenously to the rabbits (1) kills bacteria and eliminates bacteremia 30 min post challenge; (2) inhibits Toll-like receptor 4 agonists in serum 90 min post challenge; (3) reduces serum levels of pro-inflammatory cytokines (interleukin-6 and tumor necrosis factor α); and (4) reverts to hypothermia and gives rise to temperature values indistinguishable from basal levels 330 min post challenge. The two components of the combination displayed synergism in some of these activities, and Pep19-2.5 notably counteracted the endotoxin-inducing potential of ceftriaxone. Thus, the combination therapy of Pep19-2.5 and ceftriaxone holds promise as a candidate for human sepsis therapy.
Animals ; Bacteremia ; Bacteria ; Bacterial Infections ; Cause of Death ; Ceftriaxone ; Cytokines ; Homicide* ; Humans ; Hyperglycemia ; Hyperlactatemia ; Hypothermia ; Leukopenia ; Mice ; Models, Animal ; Pathology ; Rabbits* ; Salmonella enterica ; Sepsis* ; Toll-Like Receptor 4 ; Tumor Necrosis Factor-alpha

The prevalence of diabetes mellitus (DM) and associated diseases such as cancers are substantially increasing worldwide. About 80% of the patients with pancreatic cancer have glucose metabolism alterations. This suggests an association between type 2 DM and pancreatic cancer risk and progression. There are hypotheses that show metabolic links between the diseases, due to insulin resistance, hyperglycemia, hyperinsulinemia, low grade chronic inflammation, and alteration in the insulin-insulin-like growth factor axis. The use of diabetes medications can influence the extent of carcinogenesis of the pancreas. This study briefly reviews recent literature on investigation of metabolic link of type 2 DM, risk of carcinogenesis of the pancreas and their association, as well as the current understanding of metabolic pathways implicated in metabolism and cellular growth. The main finding of this review, although there are discrepancies, is that according to most research long-term DM does not raise the risk of pancreatic cancer. The longest duration of DM may reflect hypoinsulinemia due to treatment for hyperglycemia, but recent onset diabetes was associated with increased risk for pancreatic cancer due to hyperinsulinemia and hyperglycemia. In conclusion, the review demonstrates that type 2 DM and the duration of diabetes pose a risk for pancreatic carcinogenesis, and that there is biological link between the diseases.
Diabetes Mellitus, Type 2/complications/epidemiology/metabolism/*pathology ; Humans ; Hyperglycemia/pathology ; Insulin/metabolism ; Insulin Resistance ; Insulin-Like Growth Factor I/metabolism ; Pancreatic Neoplasms/epidemiology/*etiology ; Risk Factors

OBJECTIVETo investigate the effects of hydro-alcoholic extract of Launaea acanthodes, a blood glucose lowering plant in folk medicine of Iran, on the structure of seminiferous tubules and serum gonadotropin and testosterone levels in hyperglycemic rats.

METHODSTwenty-four Wistar rats were randomly allocated into 4 groups (n=6): control, streptozotocin (STZ), STZ + insulin [STZ + Ins, 5 IU/(kg•day)], and STZ + Launaea acanthodes extract [STZ + Ext, 150 mg/(kg•day)]. Blood samples were collected at the 2nd and 4th weeks for detection of testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH) with enzyme-linked immuno sorbent assay (ELISA), and the right testes of rats were removed at the 7th week for the evaluation of diameter and wall thickness of seminiferous tubules and number of Leydig cells using unbiased stereological techniques.

RESULTSIn comparison with the control group, at the 2nd week FSH (0.45 vs 0.03, 0.02, 0.02 IU/L in STZ, STZ + Ins and STZ + Ext groups, respectively) and LH (1.02 vs 0.37, 0.2, 0.29 IU/L) showed significant decreases (all P<0.05) and testosterone (4.2 vs 8.37, 7.78, 11.8 ng/mL) showed a remarkable increase (all P<0.05). The levels of these hormones became closer in the STZ + Ext and the STZ + Ins groups to the control at the 4th week. A significant decrease in diameter and wall thickness of seminiferous tubules and number of Leydig cells were observed in the STZ group as compared with the control (P<0.01).

CONCLUSIONSAdministration of Launaea extract demonstrated a beneficial impact on the protection of testis from pathogenic and degenerative effects of hyperglycemia which may be partly due to its potential antioxidative effects.

Animals ; Asteraceae ; chemistry ; Blood Glucose ; metabolism ; Cell Count ; Cholesterol ; blood ; Ethanol ; chemistry ; Gonadotropins ; blood ; Hyperglycemia ; blood ; drug therapy ; pathology ; Insulin ; blood ; Leydig Cells ; drug effects ; pathology ; Lipoproteins ; blood ; Male ; Plant Extracts ; pharmacology ; therapeutic use ; Rats, Wistar ; Seminiferous Tubules ; drug effects ; pathology ; Testosterone ; blood ; Triglycerides ; blood ; Water ; chemistry

Gap junctions play a critical role in electrical synchronization and exchange of small molecules between neighboring cells; connexins are a family of structurally related transmembrane proteins that assemble to form vertebrate gap junctions. Hyperglycemia changes the structure gap junction proteins and their expression, resulting in obstruction of neural regeneration, vascular function and wound healing, and also promoting vascular atherosclerosis. These pathogenic factors would cause diabetic foot ulcers. This article reviews the involvement of connexins in pathogenesis of diabetic foot.
Atherosclerosis ; Connexins ; metabolism ; Diabetic Foot ; pathology ; Gap Junctions ; metabolism ; Humans ; Hyperglycemia ; physiopathology ; Regeneration ; Wound Healing

The Goto-Kakizaki (GK) rat is a spontaneous type 2 diabetic animal model, which is characterized by a progressive loss of beta islet cells with fibrosis. In the present study, the hypoglycemic effect of asiatic acid (AA) in GK rats was examined. GK rats receiving AA at a daily dose of 25 mg·kg(-1) for four weeks showed a significant reduction in blood glucose levels. Age-matched normal Wistar rats were given 0.5% sodium carboxymethyl cellulose (CMC-Na) solution for the same periods and used as control. Compared to the normal Wistar rats, GK rats treated with AA showed improvement in insulin resistance partially through decreasing glucose level (P < 0.01) and insulin level (P < 0.05). Furthermore, the results of immunohistochemistry indicate that AA treatment reduced islet fibrosis in GK rats. Fibronectin, a key protein related to islet fibrosis, was over-expressed in GK rats, which was reversed significantly by AA treatment (P < 0.05). These findings suggest that AA has a beneficial effect on lowering blood glucose levels in GK rats and improves fibrosis of islets in diabetes, which may play a role in the prevention of islets dysfunction.
Animals ; Blood Glucose ; metabolism ; Centella ; chemistry ; Diabetes Mellitus, Type 2 ; drug therapy ; pathology ; Disease Models, Animal ; Fibronectins ; metabolism ; Fibrosis ; Glucose Tolerance Test ; Hyperglycemia ; drug therapy ; pathology ; Insulin ; blood ; Insulin Resistance ; Islets of Langerhans ; drug effects ; pathology ; Male ; Pancreatic Diseases ; metabolism ; pathology ; prevention & control ; Pentacyclic Triterpenes ; pharmacology ; therapeutic use ; Phytotherapy ; Plant Extracts ; pharmacology ; therapeutic use ; Rats, Inbred Strains

The aim of this study is to evaluate the outcomes of permissive hyperglycemia up to < 300 mg/dL in extremely-low-birth-weight infants (ELBWIs). We retrospectively reviewed the medical records of 260 live-born ELBWIs at Samsung Medical Center between 2004 and 2008, grouped according to peak blood glucose level and management during the first 14 days of life. The groups were normoglycemia (N), blood glucose < or = 200 mg/dL; permissive hyperglycemia (P), blood glucose 201-299 mg/dL without insulin treatment; treated hyperglycemia (T), blood glucose > or = 300 mg/dL with insulin. Only 15% of patients were grouped as N, with 39% as P and 46% as T. Although P had lower birth weight, P had a similar daily calorie and glucose intake as well as urine output compared to N. There was no significant correlation between blood glucose level and urine output on day 7. Compared to N, P showed faster weight gain and similar mortality, morbidities, and long-term neurological outcomes. Permissive hyperglycemia up to < 300 mg/dL without insulin treatment during the first 14 days of life is not associated with osmotic diuresis or increased mortality or morbidities, suggesting that it is not detrimental in ELBWIs.
Blood Glucose/analysis ; Demography ; Gestational Age ; Humans ; Hyperglycemia/*blood/drug therapy/mortality ; Hypoglycemic Agents/therapeutic use ; Infant, Extremely Low Birth Weight ; Infant, Newborn ; Infant, Premature, Diseases/*blood/mortality/pathology ; Intensive Care Units, Neonatal ; Odds Ratio ; Retrospective Studies ; Time Factors

This study is to evaluate the anti-diabetic effects of the alpha-glucosidase inhibitor valibose in a streptozotocin (STZ)-induced type 1 diabetes rat model. Diabetes was induced by a single dose of STZ (58 mg x kg(-1), ip) in SD rats, rats with elevated fasting blood glucose levels (250-450 mg x dL(-1)) were selected and divided into five groups (n = 10 in each). Another ten normal SD rats were chosen as normal group. Valibose mixed with the high sucrose diets (0.4, 1.0 and 2.5 mg 100 g(-1) diets) or acarbose (30 mg x 100 g(-1) diets) was administrated in the diabetic rats for about 5 weeks. In all groups, fasting and postprandial plasma glucose, plasma lipids, glycosylated serum protein, N-acetyl-beta-D-glucosaminidase (NAG), creatinine (Cre), blood urea nitrogen (BUN) and urine sugar levels were determined during the treatment. At the end of the experiment, the morphological alterations in kidney were evaluated by hematoxylin-eosin (HE) staining. After 3-weeks administration, valibose significantly decreased postprandial and fasting blood glucose, urine glucose, and reduced the levels of serum fructosamine. Valibose also decreased plasma triglyceride and cholesterol levels after 4 weeks treatment. These results indicated that valibose ameliorated metabolic disturbance of glucose and lipids in STZ-induced diabetic rats. In addition, valibose markedly reduced level of serum NAG and BUN, and decreased the weight index of kidney. HE staining showed reduced kidney pathological changes after valibose treatment. The findings of the present study indicate that valibose may be a novel alpha-glucosidase inhibitor for the prevention from hyperglycemia in STZ-induced type 1 diabetes rats. And valibose might have a potential role for protecting against diabetic nephropathy during hyperglycemia.
Acetylglucosaminidase ; blood ; Animals ; Blood Glucose ; metabolism ; Blood Urea Nitrogen ; Cholesterol ; blood ; Creatinine ; blood ; Cyclohexanols ; pharmacology ; Diabetes Mellitus, Experimental ; blood ; pathology ; Diabetic Nephropathies ; prevention & control ; Enzyme Inhibitors ; pharmacology ; Fructosamine ; blood ; Glycoside Hydrolase Inhibitors ; Hyperglycemia ; prevention & control ; Hypoglycemic Agents ; pharmacology ; Kidney ; pathology ; Male ; Rats ; Rats, Sprague-Dawley ; Triglycerides ; blood ; Weight Gain ; drug effects

Early diabetic nephropathy is characterized by glomerular hyperpermeability as a result of impaired glomerular filtration structure caused by hyperglycemia, glycated proteins or irreversible advanced glycosylation endproducts (AGE). To investigate the effect of ginseng total saponin (GTS) on the pathologic changes of podocyte ZO (zonula occludens)-1 protein and podocyte permeability induced by diabetic conditions, we cultured mouse podocytes under: 1) normal glucose (5 mM, = control); 2) high glucose (HG, 30 mM); 3) AGE-added; or 4) HG plus AGE-added conditions and treated with GTS. HG and AGE increased the dextran filtration of monolayered podocytes at early stage (2-8 hr) in permeability assay. In confocal imaging, ZO-1 colocalized with actin filaments and beta-catenin at cell contact areas, forming intercellular filtration gaps. However, these diabetic conditions suppressed ZO-1 immunostainings and disrupted the linearity of ZO-1. In Western blotting, diabetic conditions also decreased cellular ZO-1 protein levels at 6 hr and 24 hr. GTS improved such quantitative and qualitative changes. These findings imply that HG and AGE have an influence on the redistribution and amount of ZO-1 protein of podocytes thereby causing hyperpermeability at early stage, which can be reversed by GTS.
Actin Cytoskeleton/metabolism ; Animals ; Cell Line ; Diabetic Nephropathies/physiopathology ; Glomerular Filtration Rate ; Glucose/*pharmacology ; Glycosylation End Products, Advanced/*pharmacology ; Hyperglycemia/physiopathology ; Membrane Proteins/*metabolism ; Mice ; *Panax ; Permeability/drug effects ; Phosphoproteins/*metabolism ; Plant Preparations/*pharmacology ; Podocytes/drug effects/pathology/physiology ; Saponins/*pharmacology ; beta Catenin/metabolism

The aim of this study is to investigate the therapeutic effect of RegIII-proinsulin-pBudCE4.1 plasmid on streptozotocin (STZ)-induced type 1 diabetes mellitus and its underlying mechanisms. The model of type 1 diabetes mellitus was established by intraperitoneal injections of STZ (40 mg kg(-1)) to Balb/c mice for five consecutive days. Then, ten type 1 diabetic mice were intramuscularly injected with 100 microg RegIII-proinsulin-pBudCE4.1 plasmid for 4 weeks (one time/week) and the blood glucose levels were monitored every week; whereas another ten diabetic mice served as negative control group were injected with pBudCE4.1 vector at the same dose. Normal control and model control mice were treated with normal saline at identical volume under the same way. Western blotting, MTT assay, ELISA, HE staining and Tunel assay were applied to explore the underlying mechanisms. Results showed that RegIII-proinsulin-pBudCE4.1 plasmid ameliorated the hyperglycemia symptoms in diabetic mouse remarkably. It induced an immunological tolerance state in type 1 diabetic mice by inhibiting the proliferation of splenic lymphocytes and recovering Th1/Th2 balance evidenced by MTT and ELISA analysis. Furthermore, it elevated insulin concentration in the serum of type 1 diabetic mice and promoted the regeneration of beta cells supported by the results of HE staining and Tunel assay. In conclusion, RegIII-proinsulin-pBudCE4.1 plasmid possesses powerful anti-diabetic ability, which may be involved in the inducing of immunological tolerance and enhancing beta cells recovery.
Animals ; Apoptosis ; Blood Glucose ; metabolism ; Cell Proliferation ; Diabetes Mellitus, Experimental ; metabolism ; pathology ; therapy ; Diabetes Mellitus, Type 1 ; chemically induced ; metabolism ; pathology ; therapy ; Genetic Therapy ; Hyperglycemia ; therapy ; Injections, Intramuscular ; Insulin ; blood ; Islets of Langerhans ; cytology ; Male ; Mice ; Mice, Inbred BALB C ; Plasmids ; Proinsulin ; genetics ; metabolism ; therapeutic use ; Proteins ; genetics ; metabolism ; therapeutic use ; Streptozocin ; T-Lymphocytes ; cytology ; Th1-Th2 Balance