Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
J Ethnopharmacol ; 285: 114786, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-34763043

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Diabetes is a common, complex, chronic metabolic disease. A randomized, double-blind, placebo-parallel controlled clinical study has shown that Gegen Qinlian Decoction (GQD) can reduce glycosylated hemoglobin in type 2 diabetes mellitus (T2DM) intestinal damp-heat syndrome patients in a dose-dependent manner. AIM: To explore the pathogenesis of T2DM intestinal damp-heat syndrome and the therapeutic effect of GQD from the perspective of exosomal microRNA (miRNA). METHODS: Eligible patients were selected and treated with GQD for 3 months to evaluate their clinical efficacy. Effective cases were matched with healthy volunteers, and saliva samples were collected. Exosomal miRNA was extracted from saliva and analyzed by chip sequencing. Subsequently, the function of the differential gene and the signal transduction pathway were analyzed using bioinformatics technology. Finally, three target miRNAs were randomly selected from the T2DM group/healthy group, and two target miRNAs in the T2DM before treatment/after treatment group were randomly selected for qPCR verification. Finally, we conducted a correlation analysis of the miRNAs and clinical indicators. The registration number for this research is ChiCTR-IOR-15006626. RESULTS: (1) The expression of exosomal miRNA chips showed that there were 14 differentially expressed miRNAs in the T2DM group/healthy group, and 26 differentially expressed miRNAs in the T2DM before treatment/after treatment group. (2) Enrichment results showed that in the T2DM group/healthy group, it was primarily related to cell development, body metabolism, TGF-ß, and ErbB signaling pathways. In the T2DM before treatment/after treatment group, it was mainly related to cellular metabolic regulation processes, and insulin, Wnt, and AMPK signaling pathways. (3) The qPCR verification showed that the expressions of hsa-miR-9-5p, hsa-miR-150-5p, and hsa-miR-216b-5p in the T2DM group was higher (P<0.05). Following GQD treatment, hsa-miR-342-3p and hsa-miR-221-3p were significantly downregulated (P<0.05). (4) hsa-miR-9-5p was positively correlated with BMI (P<0.05), and hsa-miR-150-5p was positively correlated with total cholesterol and triglycerides (P<0.05). The GQD efficacy-related gene hsa-miR-342-3p was positively correlated with the patient's initial blood glucose level (P<0.05), and hsa-miR-221-3p was positively correlated with total cholesterol and triglycerides (P<0.05). CONCLUSION: The exosomal miRNA expression profile and signaling pathways related to T2DM intestinal damp-heat syndrome and the efficacy of GQD were established, which provides an alternative strategy for precision traditional Chinese medicine treatment.


Subject(s)
Diabetes Mellitus, Type 2 , Drugs, Chinese Herbal , Exosomes/genetics , Insulin , Intestines , MicroRNAs/analysis , Sequence Analysis, RNA/methods , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/physiopathology , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/adverse effects , Female , Glycated Hemoglobin/analysis , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/adverse effects , Insulin/deficiency , Insulin/metabolism , Intestines/metabolism , Intestines/microbiology , Intestines/physiopathology , Male , Medicine, Chinese Traditional/methods , Middle Aged , Patient Acuity , Signal Transduction/drug effects , Transforming Growth Factor beta/metabolism , Treatment Outcome
2.
J Diabetes ; 10(1): 50-58, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28371426

ABSTRACT

BACKGROUND: Solute carrier family 19 member 2 (SLC19A2) gene deficiency is one of the causes of permanent neonatal diabetes mellitus (PNDM) and can be effectively managed by thiamine supplementation. Herein we report on a male patient with a novel SLC19A2 mutation and summarize the clinical characteristics of patients with SLC19A2 deficiency. METHODS: The genetic diagnosis of the patient with PNDM was made by sequencing and quantitative polymerase chain reaction. The clinical characteristics of PNDM were summarized on the basis of a systematic review of the literature. RESULTS: The patient with PNDM had c.848G>A (p.W283X) homozygous mutation in SLC19A2. His father had a wild-type SLC19A2 (c.848G) and his mother was c.848G/A heterozygous. The patient and his father both had a diploid genotype (c.848A/A and c.848G/G). After oral thiamine administration, the patient's fasting C-peptide levels increased gradually, and there was a marked decrease in insulin requirements. A search of the literature revealed that thiamine treatment was effective and improved diabetes in 63% of patients with SLC19A2 deficiency. CONCLUSIONS: A novel SLC19A2 mutation (c.848G>A; p.W283X) was identified, which was most likely inherited as segmental uniparental isodisomy. Insulin insufficiency in PNDM caused by SLC19A2 deficiency can be corrected by thiamine supplementation. The differential diagnosis of SLC19A2 deficiency should be considered in children with PNDM accompanied by anemia or hearing defects to allow for early treatment.


Subject(s)
Diabetes Mellitus/drug therapy , Insulin/metabolism , Membrane Transport Proteins/genetics , Mutation , Thiamine/therapeutic use , Vitamin B Complex/therapeutic use , Diabetes Mellitus/genetics , Diabetes Mellitus/pathology , Homozygote , Humans , Infant , Insulin/deficiency , Male , Prognosis , Recovery of Function
3.
Poult Sci ; 96(12): 4409-4418, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-29053815

ABSTRACT

In mammals, insulin regulates blood glucose levels and plays a key regulatory role in appetite via the hypothalamus. In contrast, chickens are characterized by atypical glucose homeostasis, with relatively high blood glucose levels, reduced glucose sensitivity of pancreatic beta cells, and large resistance to exogenous insulin. The aim of the present study was to investigate in chickens the effects of 5 h fasting and 5 h insulin immuno-neutralization on hypothalamic mRNA levels of 23 genes associated with food intake, energy balance, and glucose metabolism. We observed that insulin immune-neutralization by administration of anti-porcine insulin guinea pig serum (AI) significantly decreased food intake and increased plasma glucose levels in chickens, while 5 h fasting produced a limited and non-significant reduction in plasma glucose. In addition, 5 h fasting increased levels of NPY, TAS1R1, DIO2, LEPR, GLUT1, GLUT3, GLUT8, and GCK mRNA. In contrast, AI had no impact on the levels of any selected mRNA. Therefore, our results demonstrate that in chickens, food intake inhibition or satiety mechanisms induced by insulin immuno-neutralization do not rely on hypothalamic abundance of the 23 transcripts analyzed. The hypothalamic transcripts that were increased in the fasted group are likely components of a mechanism of adaptation to fasting in chickens.


Subject(s)
Chickens/physiology , Eating/physiology , Fasting/physiology , Gene Expression , Insulin/metabolism , Animals , Chickens/genetics , Hypothalamus/metabolism , Insulin/deficiency , RNA, Messenger/genetics , RNA, Messenger/metabolism
4.
PLoS One ; 8(8): e71944, 2013.
Article in English | MEDLINE | ID: mdl-23967267

ABSTRACT

This study tested whether chronic systemic administration of 5-aminoimidazole-4-carboxamide-1-ß-D-ribofuranoside (AICAR) could attenuate hyperphagia, reduce lean and fat mass losses, and improve whole-body energy homeostasis in insulin-deficient rats. Male Wistar rats were first rendered diabetic through streptozotocin (STZ) administration and then intraperitoneally injected with AICAR for 7 consecutive days. Food and water intake, ambulatory activity, and energy expenditure were assessed at the end of the AICAR-treatment period. Blood was collected for circulating leptin measurement and the hypothalami were extracted for the determination of suppressor of cytokine signaling 3 (SOCS3) content, as well as the content and phosphorylation of AMP-kinase (AMPK), acetyl-CoA carboxylase (ACC), and the signal transducer and activator of transcription 3 (STAT3). Rats were thoroughly dissected for adiposity and lean body mass (LBM) determinations. In non-diabetic rats, despite reducing adiposity, AICAR increased (∼1.7-fold) circulating leptin and reduced hypothalamic SOCS3 content and food intake by 67% and 25%, respectively. The anorexic effect of AICAR was lost in diabetic rats, even though hypothalamic AMPK and ACC phosphorylation markedly decreased in these animals. Importantly, hypothalamic SOCS3 and STAT3 levels remained elevated and reduced, respectively, after treatment of insulin-deficient rats with AICAR. Diabetic rats were lethargic and displayed marked losses of fat and LBM. AICAR treatment increased ambulatory activity and whole-body energy expenditure while also attenuating diabetes-induced fat and LBM losses. In conclusion, AICAR did not reverse hyperphagia, but it promoted anti-catabolic effects on skeletal muscle and fat, enhanced spontaneous physical activity, and improved the ability of rats to cope with the diabetes-induced dysfunctional alterations in glucose metabolism and whole-body energy homeostasis.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Aminoimidazole Carboxamide/analogs & derivatives , Hypothalamus/drug effects , Hypothalamus/metabolism , Insulin/deficiency , Ribonucleosides/administration & dosage , Ribonucleosides/pharmacology , Acetyl-CoA Carboxylase/metabolism , Adipose Tissue/drug effects , Adipose Tissue/metabolism , Aminoimidazole Carboxamide/administration & dosage , Aminoimidazole Carboxamide/pharmacology , Animals , Appetite Depressants/administration & dosage , Appetite Depressants/pharmacology , Body Composition/drug effects , Body Weight/drug effects , Diabetes Mellitus/blood , Diabetes Mellitus/metabolism , Diabetes Mellitus/pathology , Diabetes Mellitus/physiopathology , Drinking/drug effects , Energy Metabolism/drug effects , Hypothalamus/physiopathology , Insulin/blood , Leptin/blood , Leptin/metabolism , Male , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Phosphorylation/drug effects , Rats , Rats, Wistar , STAT3 Transcription Factor/metabolism , Signal Transduction/drug effects , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins/metabolism
5.
J Physiol Biochem ; 67(1): 121-8, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21080139

ABSTRACT

Diabetes mellitus, with its attendant disorders and dysfunctional behaviors, constitutes a growing concern to the population of the world. With this concern in mind, the present study investigated the anti-diabetic and hypolipedimic potential of 17ß-estradiol (called E2), particularly in terms of its inhibitory effects on maltase, sucrase, lactase, and lipase activities in the intestine of surviving diabetic rats. The findings revealed that this supplement helped protect the ß cells of the rats from death and damage. Interestingly, E2 induced considerable decreases of 29%, 46%, 42%, and 84% in the activities of intestinal maltase, lactase, sucrase, and lipase, respectively. The E2 extract also decreased the glucose, triglyceride, and total cholesterol rates in the plasma of diabetic rats by 39%, 27%, and 53%, respectively, and increased the HDL-cholesterol level by 74%, which helped maintain the homeostasis of blood lipid. When compared to those of the untreated diabetic rats, the superoxide dismutase, catalase, and glutathione peroxidase levels in the pancreas of the rats treated with this supplement were also enhanced by 330%, 170%, and 301%, respectively. A significant decrease was also observed in the lipid peroxidation level and lactate dehydrogenase activity in the pancreas of diabetic rats after E2 administration. Overall, the findings presented in this study demonstrate that E2 has both a promising potential with regard to the inhibition of intestinal maltase, sucrase, lactase, and lipase activities, and a valuable hypoglycemic and hypolipidemic function, which make it a potential strong candidate for industrial application as apharmacological agent for the treatment and prevention of hyperlipidemia, obesity, and cardiovascular diseases.


Subject(s)
Diabetes Mellitus/drug therapy , Estradiol/pharmacology , Estrogens/pharmacology , Insulin/deficiency , Insulin/metabolism , Pancreas/drug effects , Animals , Blood Glucose/drug effects , Blood Glucose/metabolism , Catalase/drug effects , Catalase/metabolism , Cholesterol/blood , Cholesterol/metabolism , Cholesterol, HDL/drug effects , Cholesterol, HDL/metabolism , Diabetes Mellitus/metabolism , Glutathione Peroxidase/drug effects , Glutathione Peroxidase/metabolism , L-Lactate Dehydrogenase/drug effects , L-Lactate Dehydrogenase/metabolism , Lactase/drug effects , Lactase/metabolism , Lipase/drug effects , Lipase/metabolism , Lipid Peroxidation/drug effects , Pancreas/anatomy & histology , Pancreas/cytology , Rats , Sucrase/drug effects , Sucrase/metabolism , Superoxide Dismutase/metabolism , Superoxide Dismutase/pharmacology , Superoxide Dismutase/therapeutic use , Triglycerides/blood , Triglycerides/metabolism , alpha-Glucosidases/drug effects , alpha-Glucosidases/metabolism
6.
Diabetologia ; 46(10): 1329-37, 2003 Oct.
Article in English | MEDLINE | ID: mdl-12928770

ABSTRACT

AIMS/HYPOTHESIS: The purpose of this study was to assess the therapeutic implication of leptin in insulin-deficient diabetes. METHODS: Insulin-deficient diabetes was induced by streptozotocin (STZ) in transgenic skinny mice overexpressing leptin. Plasma concentrations of glucose, insulin, and leptin were measured. The effects on body weight, food intake, and hypothalamic gene expressions were analyzed. After diabetes was induced, graded doses of insulin ranging from 0.4 to 51.2 mU.g(-1).day(-1) were injected. Co-administration of leptin and insulin was also carried out using osmotic pumps. RESULTS: After STZ injection, both transgenic and non-transgenic littermates developed marked hyperglycaemia as a result of severe hypoinsulinaemia [termed diabetic transgenic skinny mice overexpressing leptin (diabetic TGM) and diabetic non-transgenic littermates (diabetic WT) respectively], although diabetic TGM were more sensitive to exogenously administered insulin than diabetic WT. Diabetic WT were hypoleptinaemic and hyperphagic relative to non-diabetic WT, whereas diabetic TGM, which remained hyperleptinaemic, were less hyperphagic than diabetic WT. After STZ injection, hypothalamic expressions of orexigenic and anorexigenic peptide mRNAs were up-regulated and down-regulated, respectively, in diabetic WT, whereas they were unchanged in diabetic TGM. Diabetic TGM became normoglycaemic, when treated with insulin at such doses that did not improve hyperglycaemia in diabetic WT. We found that a sub-threshold dose of insulin that does not affect glucose homeostasis is effective in improving the diabetes in normal mice rendered diabetic by STZ injection, when combined with leptin. CONCLUSIONS/INTERPRETATION: This study suggests that leptin could be used as an adjunct of insulin therapy in insulin-deficient diabetes, thereby providing an insight into the therapeutic implication of leptin as an anti-diabetic agent.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Insulin/deficiency , Insulin/pharmacology , Leptin/pharmacology , Agouti-Related Protein , Animals , Dose-Response Relationship, Drug , Drug Administration Schedule , Drug Combinations , Hypothalamus/metabolism , Insulin/administration & dosage , Intercellular Signaling Peptides and Proteins , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neuropeptide Y/genetics , Pro-Opiomelanocortin/genetics , Proteins/genetics , RNA, Messenger/metabolism
7.
BMC Physiol ; 3: 5, 2003 Jul 09.
Article in English | MEDLINE | ID: mdl-12848900

ABSTRACT

BACKGROUND: Fasting and diabetes are characterized by elevated glucocorticoids and reduced insulin, leptin, elevated hypothalamic AGRP and NPY mRNA, and reduced hypothalamic POMC mRNA. Although leptin replacement can reverse changes in hypothalamic gene expression associated with fasting and diabetes, leptin also normalizes corticosterone; therefore the extent to which the elevated corticosterone contributes to the regulation of hypothalamic gene expression in fasting and diabetes remains unclear. To address if elevated corticosterone is necessary for hypothalamic responses to fasting and diabetes, we assessed the effects of adrenalectomy on hypothalamic gene expression in 48-hour-fasted or diabetic mice. To assess if elevated corticosterone is sufficient for the hypothalamic responses to fasting and diabetes, we assessed the effect of corticosterone pellets implanted for 48 hours on hypothalamic gene expression. RESULTS: Fasting and streptozotocin-induced diabetes elevated plasma glucocorticoid levels and reduced serum insulin and leptin levels. Adrenalectomy prevented the rise in plasma glucocorticoids associated with fasting and diabetes, but not the associated reductions in insulin or leptin. Adrenalectomy blocked the effects of fasting and diabetes on hypothalamic AGRP, NPY, and POMC expression. Conversely, corticosterone implants induced both AGRP and POMC mRNA (with a non-significant trend toward induction of NPY mRNA), accompanied by elevated insulin and leptin (with no change in food intake or body weight). CONCLUSION: These data suggest that elevated plasma corticosterone mediate some effects of fasting and diabetes on hypothalamic gene expression. Specifically, elevated plasma corticosterone is necessary for the induction of NPY mRNA with fasting and diabetes; since corticosterone implants only produced a non-significant trend in NPY mRNA, it remains uncertain if a rise in corticosterone may be sufficient to induce NPY mRNA. A rise in corticosterone is necessary to reduce hypothalamic POMC mRNA with fasting and diabetes, but not sufficient for the reduction of hypothalamic POMC mRNA. Finally, elevated plasma corticosterone is both necessary and sufficient for the induction of hypothalamic AGRP mRNA with fasting and diabetes.


Subject(s)
Diabetes Mellitus, Experimental/physiopathology , Fasting/physiology , Gene Expression Regulation/physiology , Glucocorticoids/physiology , Hypothalamus/physiology , Hypothalamus/physiopathology , Adrenal Medulla/physiology , Adrenal Medulla/physiopathology , Adrenal Medulla/surgery , Adrenalectomy/methods , Agouti-Related Protein , Animals , Corticosterone/administration & dosage , Corticosterone/pharmacology , Diabetes Mellitus, Experimental/blood , Drug Implants/pharmacology , Gene Expression Regulation/drug effects , Glucocorticoids/blood , Hypothalamus/drug effects , Insulin/deficiency , Insulin/genetics , Insulin/physiology , Intercellular Signaling Peptides and Proteins , Leptin/genetics , Male , Mice , Mice, Inbred C57BL , Neuropeptide Y/genetics , Pro-Opiomelanocortin/genetics , Proteins/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism
8.
Diabetes ; 48(7): 1487-92, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10389859

ABSTRACT

Leptin has been shown to improve insulin sensitivity and glucose metabolism in normoinsulinemic healthy or obese rodents. It has not been determined whether leptin may act independently of insulin in regulating energy metabolism in vivo. The present study was designed to examine the effects of leptin treatment alone on glucose metabolism in insulin-deficient streptozotocin (STZ)-induced diabetic rats. Four groups of STZ-induced diabetic rats were studied: 1) rats treated with recombinant methionine murine leptin subcutaneous infusion with osmotic pumps for 12-14 days (LEP; 4 mg x kg(-1) x day(-1), n = 10); 2) control rats infused with vehicle (phosphate-buffered saline) for 12-14 days (VEH; n = 10); 3) pair-fed control rats given a daily food ration matching that of LEP rats for 12-14 days (PF; n = 8); and 4) rats treated with subcutaneous phloridzin for 4 days (PLZ; 0.4 g/kg twice daily, n = 10). Phloridzin treatment normalizes blood glucose without insulin and was used as a control for the effect of leptin in correcting hyperglycemia. All animals were then studied with a hyperinsulinemic-euglycemic clamp (6 mU x kg(-1) x min(-1). Our study demonstrates that leptin treatment in the insulin-deficient diabetic rats restored euglycemia, minimized body weight loss due to food restriction, substantially improved glucose metabolic rates during the postabsorptive state, and restored insulin sensitivities at the levels of the liver and the peripheral tissues during the glucose clamp. The effects on glucose turnover are largely independent of food restriction and changes in blood glucose concentration, as evidenced by the minimal improvement of insulin action and glucose turnover parameters in the PF and PLZ groups. Our results suggest that the antidiabetic effects of leptin are achieved through both an insulin-independent and an insulin-sensitizing mechanism.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Glucose/metabolism , Insulin/deficiency , Obesity/blood , Proteins/therapeutic use , Animals , Diabetes Mellitus, Experimental/blood , Drug Evaluation, Preclinical , Glucose Clamp Technique , Leptin , Male , Phlorhizin/therapeutic use , Rats , Rats, Sprague-Dawley
9.
Lipids ; 31 Suppl: S33-6, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8729090

ABSTRACT

Insulin and dietary fructose independently induce stearoyl-CoA desaturase 1 (SCD1) gene expression in diabetic mouse liver. In the present study, we again used diabetic mice and supplemented a high fructose diet with polyunsaturated fatty acids (PUFA) to determine the selective repression of SCD1 gene expression by dietary PUFA, as previously shown in normal mice. We saw dramatic repression of SCD1 mRNA expression, with trilinolenin at 3% and triarachidonin at 1% supplementation. We also observed significant repression of insulin-induced SCD1 mRNA upon supplementation of the noninducing starch diet with PUFA. In conclusion, our data demonstrate that PUFA negatively regulate hepatic gene expression through an insulin-independent mechanism.


Subject(s)
Diabetes Mellitus, Experimental/genetics , Dietary Fats, Unsaturated/pharmacology , Gene Expression Regulation, Enzymologic/physiology , Insulin/pharmacology , RNA, Messenger/metabolism , Stearoyl-CoA Desaturase/genetics , 5,8,11,14-Eicosatetraynoic Acid/analogs & derivatives , 5,8,11,14-Eicosatetraynoic Acid/pharmacology , Animals , Fructose/pharmacology , Insulin/deficiency , Male , Mice , Mice, Inbred BALB C , Triglycerides , alpha-Linolenic Acid/analogs & derivatives , alpha-Linolenic Acid/pharmacology
10.
J Lipid Res ; 34(9): 1527-34, 1993 Sep.
Article in English | MEDLINE | ID: mdl-7693843

ABSTRACT

The adipocyte fatty acid-binding protein, aP2 or ALBP, is an abundant cytosolic protein postulated to function in binding and intracellular transport of long-chain fatty acids. In this report, we investigated levels of aP2 mRNA and protein and transcriptional activity of the aP2 gene in tissues from streptozotocin-diabetic rats at different time periods following the induction of diabetes. An average 75% decrease in mRNA for aP2 (relative to mRNA for beta-actin) was observed in all diabetic rats at 7 days post-STZ injection. Insulin supplementation rapidly (2 h) restored aP2 mRNA and the insulin effect was cycloheximide-sensitive. Nuclear transcription assays measured a 60% decrease in transcription of the aP2 gene in diabetic rats that was reversed by insulin administration. Levels of aP2 protein were still high, in some cases, 1 day after the decrease in mRNA levels consistent with a long half-life of the protein. Decreases in aP2 protein were rapidly reversed by insulin administration. There were no changes in aP2 protein in the absence of changes in aP2 mRNA supporting a pretranslational mechanism of regulation. The decrease in aP2 mRNA was delayed in onset when compared with the rapid decline (at day 2 of diabetes) of mRNA for the lipogenic enzyme, fatty acid synthase, and with the accelerated depletion of adipose tissue lipid. Adipose tissue weight and lipid content had decreased by more than 80% 3 days before any significant changes in aP2 expression were observed. Changes in aP2 could not be related to changes in the levels of circulating fatty acids that regulate aP2 expression in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Adipocytes/physiology , Carrier Proteins/biosynthesis , Diabetes Mellitus, Experimental/metabolism , Insulin/deficiency , Insulin/pharmacology , Neoplasm Proteins , Nerve Tissue Proteins , Animals , Blood Glucose/analysis , Carrier Proteins/genetics , Diabetes Mellitus, Experimental/genetics , Fatty Acid-Binding Protein 7 , Fatty Acid-Binding Proteins , Fatty Acids/blood , Fatty Acids/genetics , Gene Expression/genetics , Immunoblotting , Insulin/blood , Male , RNA/analysis , Rats , Rats, Sprague-Dawley , Transcription, Genetic/genetics
11.
Peptides ; 13(4): 721-7, 1992.
Article in English | MEDLINE | ID: mdl-1437714

ABSTRACT

Untreated insulin-deficient diabetes causes hyperphagia and neuroendocrine disturbances that may be partly mediated by increased hypothalamic activity of neuropeptide Y (NPY), a potent central appetite stimulant. The metabolic signal that stimulates hypothalamic NPY is unknown. This study aimed to determine whether insulin deficiency or hyperglycemia was responsible. Regional hypothalamic NPY concentrations were compared in streptozocin-diabetic (STZ-D) rats rendered nearly normoglycemic by either insulin replacement or food restriction. Untreated STZ-D rats were hyperphagic and showed significantly increased (p less than 0.01) hypothalamic NPY concentrations in the arcuate nucleus and lateral hypothalamic area. Once-daily ultralente insulin injections corrected hypoinsulinemia and hyperglycemia, abolished hyperphagia, and normalized NPY concentrations in all hypothalamic regions. By contrast, food restriction effectively lowered glycemia without raising insulin levels. In these underfed diabetic rats, NPY concentrations rose further and were significantly higher than nondiabetic and untreated diabetic levels in most hypothalamic regions. We conclude that insulin deficiency is a major stimulus to hypothalamic NPY in STZ-D, whereas hyperglycemia may exert an inhibitory influence. These findings support the hypothesis that hypothalamic NPY responds to specific metabolic cues and is involved in regulating energy balance and conserving body weight.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Food Deprivation/physiology , Hypothalamus/metabolism , Insulin/deficiency , Neuropeptide Y/metabolism , Animals , Hypothalamus/drug effects , Insulin/pharmacology , Male , Rats , Rats, Wistar
12.
Peptides ; 12(3): 425-30, 1991.
Article in English | MEDLINE | ID: mdl-1923923

ABSTRACT

Hypothalamic concentrations of neuropeptide Y (NPY), a potent central appetite stimulant, increase dramatically in food-restricted and insulin-deficient diabetic rats. This suggest that NPY may drive hyperphagia in these conditions, which are characterized by weight loss and insulin deficiency. To test the hypothesis that insulin deficiency and weight loss are specific stimuli to hypothalamic NPY, we measured NPY concentrations in individual hypothalamic regions in rats with hyperphagia caused by insulin-induced hypoglycemia. Groups of 8 male Wistar rats were injected with ultralente insulin (20-60 U/kg) to induce either acute hypoglycemia (7 h after a single injection) or chronic hypoglycemia (8 days with daily injections). In hypoglycemic rats, plasma insulin concentrations were increased 6- to 7-fold compared with saline-injected controls; food intake was significantly increased with acute and chronic hypoglycemia and weight gain was significantly increased in the chronically hypoglycemic group. NPY concentrations were measured by radioimmunoassay in 8 hypothalamic regions microdissected from fresh brain slices. NPY concentrations were not increased in any region in either acute or chronic hypoglycemia. NPY therefore seems unlikely to mediate hyperphagia in hyperinsulinemia-induced hypoglycemia, supporting the hypothesis that weight loss is a specific stimulus to hypothalamic NPY and that insulin deficiency may be the metabolic signal responsible.


Subject(s)
Hyperphagia/metabolism , Hypoglycemia/metabolism , Neuropeptide Y/metabolism , Animals , Blood Glucose/metabolism , Feeding Behavior/physiology , Hyperphagia/etiology , Hypoglycemia/complications , Hypothalamus/metabolism , Insulin/deficiency , Male , Rats , Rats, Inbred Strains
13.
Metabolism ; 35(1): 78-87, 1986 Jan.
Article in English | MEDLINE | ID: mdl-3510365

ABSTRACT

Conditions of decreased nutrient supply (malnutrition) and/or decreased nutrient utilization (diabetes) are attended by impairment of growth despite an increase in circulating levels of growth hormone (GH). Growth involves the actions of somatomedins, circulating insulinlike polypeptides with anabolic effects on cartilage, fat, and muscle. In malnutrition and diabetes, mechanisms of growth impairment appear to include a decrease in GH-induced generation of somatomedins, together with an increase in somatomedin inhibitors, factors which antagonize somatomedin action. Brain mediation of these alterations involves a rise in GH secretion due to decreased negative feedback from somatomedins, perhaps accentuated by blunting of feedback via actions of somatomedin inhibitors. In combination these processes lead to shunting of metabolic fuels toward vital processes and away from growth (via decreased somatomedin action) and to protein-sparing and increase in alternate metabolic fuels (via direct GH actions on muscle and fat). Further study of involved hypothalamic and pituitary mechanisms should yield additional insights into the role of the brain in metabolic homeostasis.


Subject(s)
Brain Chemistry , Nutritional Physiological Phenomena , Somatomedins/physiology , Adipose Tissue/metabolism , Animals , Diabetes Mellitus/blood , Energy Metabolism , Feedback , Growth , Growth Hormone/physiology , Hemostasis , Humans , Hypothalamus/physiology , Insulin/deficiency , Liver/physiology , Muscles/metabolism , Nutrition Disorders/blood , Nutrition Disorders/physiopathology , Pituitary Gland/physiology , Somatomedins/blood
14.
Am J Physiol ; 242(5): E335-42, 1982 May.
Article in English | MEDLINE | ID: mdl-7044142

ABSTRACT

Insulin plays a central role in metabolic control after a mixed meal. In the absence of adequate meal insulin release, abnormal circulating concentrations of most meal-derived metabolic substrates can be expected. To quantify these abnormalities in depth, responses of six pancreatectomized dogs on long-term intravenous insulin replacement were compared to those of five normal control dogs. Blood samples were drawn hourly for 24 h via a chronic indwelling catheter, and all animals ate a single mixed meal. To establish whether there were route-related differences, insulin was delivered into either the portal or the peripheral circulation of the diabetic animals at constant rates. These insulin infusion rates resulted in premeal fasting normoglycemia and in normal levels of insulin, glucagon, lactate, pyruvate, 3-hydroxybutyrate, nonesterified fatty acids, and 9 of 13 amino acids. In the absence of enhanced meal insulin infusion, the subsequent responses of glucose, lactate, pyruvate, alanine, and 10 of 13 other blood amino acids were exaggerated in terms of both amplitude and duration. Only minor or transient differences were attributable to the routes of insulin infusion. Remarkably, in spite of these abnormal postmeal responses, basal insulin alone (with constant circulating levels) succeeded in restoring all metabolite and hormonal levels during the postabsorptive period 16-23 h after the meal. Thus, with intravenous insulin infusions, the requirements for fasting metabolic normalization may be considered independently of those for metabolic control following caloric intake. It remains to be shown how prolonged deprivation of the postprandial insulin supplement results in metabolic decompensation under these conditions.


Subject(s)
Diet , Eating , Insulin/deficiency , Pancreatectomy , Animals , Diabetes Mellitus/metabolism , Dogs , Male , Reference Values
15.
Probl Endokrinol (Mosk) ; 25(6): 47-50, 1979.
Article in Russian | MEDLINE | ID: mdl-118444

ABSTRACT

Experiments conducted on female Wistar rats showed that 24 hours after the injury of the ventromedial nuclei of the hypothalamus (VMNH) without animal starvation there occurred a slight reduction of insulin in the islets and a significant elevation of the blood immunoreactive insulin (IRI) level, without any glycemia reduction. In animals with intact VMNH glybenclamide produced no changes in the insulin depot in the pancreatic cells, but somewhat increased the IRI level. However, after the VMNH injury glybenclamide caused a sharp insulin depletion in the islets, and a marked elevation of IRI and a decrease of sugar in the blood.


Subject(s)
Glyburide/pharmacology , Hypothalamus/surgery , Insulin/metabolism , Paraventricular Hypothalamic Nucleus/surgery , Animals , Antigens , Blood Glucose/antagonists & inhibitors , Female , Hypoglycemia/chemically induced , Insulin/blood , Insulin/deficiency , Insulin Antagonists/pharmacology , Insulin Secretion , Islets of Langerhans/metabolism , Rats
17.
Am J Physiol ; 232(3): E286-93, 1977 Mar.
Article in English | MEDLINE | ID: mdl-14511

ABSTRACT

Metabolism of perfused livers from control and ventromedial hypothalamus (VMH)-lesioned rats has been studied. To eliminate the possibility that observed metabolic abnormalities could be realted to hyperphagia, VMH-lesioned rats were placed on restricted diet matching that of controls. Ten days postoperatively, VMH-lesioned rats had hyperinsulinemia, hypertriglyceridemia, increased blood urea nitrogen levels, together with decreased plasma free fatty acid (FFA) and glucose levels. Insulin release produced in vivo by a glucose load was much higher in VMH-lesioned than in control rats. Perfused livers from VMH-lesioned rats secreted more triglycerides and produced more urea than controls, whereas production of glucose and ketone bodies was reduced. Lipogenesis, newly synthesized triglyceride secretion, and the activity of acetyl-CoA carboxylase and fatty acid synthetase were greatest in livers from VMH-lesioned rats. Fasting abolished hyperinsulinemia and most of these observed metabolic alterations. After treatment with anti-insulin serum, the high rate of lipogenesis observed in livers from VMH-lesioned rats was restored toward normal. It is suggested that hyperinsulinemia may be partly responsible for the metabolic disorders observed in livers from nonhyperphagic VMH-lesioned rats.


Subject(s)
Hypothalamus, Middle/physiopathology , Hypothalamus/physiopathology , Liver/metabolism , Acetyl-CoA Carboxylase/metabolism , Animals , Fasting , Fatty Acids/metabolism , Female , Food , Glucagon/blood , Glucose/metabolism , Glycogen/metabolism , Immune Sera/pharmacology , Insulin/blood , Insulin/deficiency , Insulin/immunology , Ketone Bodies/metabolism , Lipids/biosynthesis , Rats , Triglycerides/blood , Urea/metabolism
18.
Probl Endokrinol (Mosk) ; 22(6): 65-71, 1976.
Article in Russian | MEDLINE | ID: mdl-798183

ABSTRACT

The work was aimed at detection and precise localization of the hypothalamic nuclei sensitive to insulin deficiency. For this purpose nuclei of the whole hypothalamic area of the brain were examined in rats with experimentally-induced alloxan diabetes. Only individual nuclei, particularly the supraoptic nucleus of the anterior hypothalamus and the ventro-medial and the arcuate nuclei of the medial hypothalamus proved to react to insulin deficiency. The nuclei of the posterior hypothalamus failed to react to insulin deficiency. Possible ways and methods of participation of the insulin-dependent areas of the hypothalamus in the regulation of the endocrine function of the pancreas are discussed.


Subject(s)
Diabetes Mellitus, Experimental/pathology , Hypothalamus/pathology , Islets of Langerhans/pathology , Animals , Cell Nucleus , Hypothalamus, Anterior/pathology , Hypothalamus, Middle/pathology , Hypothalamus, Posterior/pathology , Insulin/deficiency , Karyometry , Male , Rats
19.
Arch Surg ; 111(3): 229-33, 1976 Mar.
Article in English | MEDLINE | ID: mdl-816331

ABSTRACT

The controversy as to the relationship between the degree of control of diabetes and the progression of the complications of the disease has not been solved. However, in this review, various studies suggesting a relationship between the metabolic abnormality and the diabetic complications are examined. The disadvantages of the uncontrolled diabetes mellitus can be divided into two major categories-short-term and long-term. The short-term disadvantages of controlled diabetes mellitus include the following: (1) ketoacidosis and hyperosmolar coma; (2) intracellular dehydration; (3) electrolyte imbalance; (4) decreased phagocytosis; (5) immunologic and lymphocyte activity; (6) impairment of wound healing; and (7) abnormality of lipids. The long-term disadvantages of uncontrolled diabetes melitus include the following: (1) nephropathy; (2) neuropathy; (3) retinopathy; (4) cataract formation; (5) effect on perinatal mortality; (6) complications of vascular disease; and (7) the evaluation of various clinical studies suggesting the relationship of elevated blood glucose levels and complications of diabetes mellitus. It is suggested that until the question of control can absolutely be resolved, the recommendation is that the blood glucose levels should be controlled as close to the normal as possible.


Subject(s)
Blood Glucose , Diabetes Complications , Insulin/deficiency , Acidosis/etiology , Adult , Animals , Dehydration/etiology , Diabetes Mellitus/therapy , Diabetic Angiopathies/etiology , Diabetic Coma/etiology , Diabetic Neuropathies/etiology , Dogs , Fatty Acids/metabolism , Female , Fetal Death/complications , Hepatolenticular Degeneration/etiology , Humans , Hyperlipidemias/etiology , Keto Acids/metabolism , Long-Term Care , Phagocytosis/drug effects , Phosphorus/metabolism , Potassium/metabolism , Pregnancy , Rats , Sodium/metabolism , Time Factors , Water-Electrolyte Imbalance/etiology , Wound Healing
SELECTION OF CITATIONS
SEARCH DETAIL