Glucose Tolerance In Rats Research Articles

Variation of Interstitial Glucose Measurements Assessed by Continuous Glucose Monitors in Healthy, Nondiabetic Individuals

OBJECTIVETo characterize glucose levels during daily living using continuous glucose monitors (CGMs) in nondiabetic individuals.RESEARCH DESIGN AND METHODSSeventy-four healthy children, adolescents, and adults aged 9–65 years with normal glucose tolerance used a blinded CGM device for 3 to 7 days.RESULTSSensor glucose concentrations were 71–120 mg/dl for 91% of the day. Sensor values were ≤60 or >140 mg/dl for only 0.2% and 0.4% of the day, respectively. Sensor glucose concentrations were slightly higher in children than adults (P = 0.009) and were slightly lower during the night than day (95 vs. 99 mg/dl, P < 0.001).CONCLUSIONSGlucose values ≤60 and >140 mg/dl, measured with CGM, are uncommon in healthy, nondiabetic individuals. CGM may be useful to evaluate glucose tolerance in nondiabetic individuals over time. Furthermore, these data provide a basis for comparison for studies that use CGM to assess glucose control in subjects with diabetes.

Low prevalence of glucose intolerance in racially mixed children with cystic fibrosis

To evaluate glucose tolerance in racially mixed Brazilian youth with cystic fibrosis (CF). Cross-sectional study conducted between August and September 2007, at a reference service for CF, evaluating: glycated hemoglobin (HbA1c), blood glucose, and insulin levels, before and 2 h after a glucose overload. There were 46 patients aged between 6 yr and 16 yr and 2 months (median: 9 yr and 10 months) of whom 64% were boys. Of these, 26% were Whites; 54.4% Mulattoes; and 19.6% Blacks. HbA1c was normal in all patients. Only one participant (12-yr old) had glucose intolerance. Insulin levels ranged from 1 to 23 µIU/mL (median: 4.5 µIU/mL) at baseline and from 3.2 to 192.1 µIU/mL (median: 11 µIU/mL) after a glucose overload. Insulin resistance evaluated by the HOMA index, stratified by sex and age, was present in three patients. The ΔF508 mutation was present in only 4.3% of the sample, all of them being heterozygous. The low prevalence of carbohydrate intolerance in this population is probably a result of their young age. Another possibility is the low frequency of the ΔF508 mutation. Although not conclusive, these data suggest that in addition to age, the genotype:phenotype ratio may influence the development of glucose intolerance in patients with CF.

Intima-media thickness and liver histology in obese children and adolescents with non-alcoholic fatty liver disease

Objective To evaluate the relationship between biopsy-proven non-alcoholic fatty liver disease (NAFLD) and carotid artery intima-media thickness (CIMT) in children and adolescents. Methods A case–control study was performed. Cases were 31 mostly obese children and adolescents, with NAFLD detected at ultrasonography, and confirmed by liver biopsy. Controls were 49 mostly obese children matched for gender, age and BMI without NAFLD at ultrasonography and with normal levels of aminotransferases. Besides standard laboratory measurements, subjects underwent an oral glucose tolerance test to evaluate glucose tolerance and to estimate whole body insulin sensitivity (ISI). Results CIMT was similar in cases and controls on the right side but higher in cases on the left side. Although statistically significant, this difference is unlikely to be clinically relevant because of substantial overlap of CIMT values between cases and controls. Moreover, there was no association between CIMT and the severity of steatosis, ballooning, fibrosis, and the non-alcoholic steato-hepatitis score in cases. At multivariable analysis in the pooled sample ( n = 80), age and the z-score of BMI but not NAFLD, gender, blood pressure and triglycerides, were associated with CIMT. Conclusions We found no association between CIMT and NAFLD in children and adolescents. More importantly, there was no association between histological severity and CIMT in children with NAFLD.

Clozapine and quetiapine acutely reduce glucagon-like peptide-1 production and increase glucagon release in obese rats: Implications for glucose metabolism and food choice behaviour

Objective Second generation antipsychotic drug (SGA) treatment is associated with detrimental effects on glucose metabolism which is often attributed to the development of obesity and insulin resistance. However, we have recently demonstrated that clozapine and quetiapine also have direct effects of glucose metabolism in animals. This study compares clozapine and quetiapine and investigates the effects of these on the development of obesity and the direct effects of these drugs on glucose metabolism compared with those caused by the obesity per se. Research design and methods Three groups of male Sprague–Dawley rats were fed a high fat/high sugar diet to induce obesity while another three groups were fed a chow diet. One group on each diet was injected daily with vehicle, clozapine or quetiapine and effects on glucose metabolism were monitored. Results Clozapine and quetiapine treatment did not directly cause obesity or potentiate diet induced obesity but did induce a preference for the high fat/high sugar diet. Neither drug caused a impairment in insulin tolerance over that caused by obesity but both drugs acutely induced impairments in glucose tolerance that were additive with the effects induced by the diet induced obesity. Both drugs caused increases in glucagon levels and a suppression of GLP-1. We investigated two strategies for restoring GLP-1 signalling. The DPP-IV inhibitor sitagliptin only partially restored GLP-1 levels and did not overcome the deleterious effects on glucose tolerance whereas the GLP-1 receptor agonist exendin-4 normalised both glucagon levels and glucose metabolism. Conclusions Our findings indicate that the clozapine and quetiapine induced impairments in glucose tolerance in rats are independent of insulin resistance caused by obesity and that these defects are linked with a suppression of GLP-1 levels. These studies suggest the need to perform follow up studies in humans to determine whether clozapine and quetiapine induce acute derangements in glucose metabolism and whether GLP-1 replacement therapy might be the most appropriate therapeutic strategy for treating derangements in glucose metabolism in subjects taking these drugs.

The Effect of Angiotensin-Converting Enzyme Inhibition Using Captopril on Energy Balance and Glucose Homeostasis

Increasing evidence suggests that the renin-angiotensin-system contributes to the etiology of obesity. To evaluate the role of the renin-angiotensin-system in energy and glucose homeostasis, we examined body weight and composition, food intake, and glucose tolerance in rats given the angiotensin-converting enzyme inhibitor, captopril ( approximately 40 mg/kg . d). Rats given captopril weighed less than controls when fed a high-fat diet (369.3 +/- 8.0 vs. 441.7 +/- 8.5 g after 35 d; P < 0.001) or low-fat chow (320.1 +/- 4.9 vs. 339.8 +/- 5.1 g after 21 d; P < 0.0001). This difference was attributable to reductions in adipose mass gained on high-fat (23.8 +/- 2.0 vs. 65.12 +/- 8.4 g after 35 d; P < 0.0001) and low-fat diets (12.2 +/- 0.7 vs. 17.3 +/- 1.3 g after 21 d; P < 0.001). Rats given captopril ate significantly less [3110.3 +/- 57.8 vs. 3592.4 +/- 88.8 kcal (cumulative 35 d high fat diet intake); P < 0.001] despite increased in neuropeptide-Y mRNA expression in the arcuate nucleus of the hypothalamus and had improved glucose tolerance compared with free-fed controls. Comparisons with pair-fed controls indicated that decreases in diet-induced weight gain and adiposity and improved glucose tolerance were due, primarily, to decreased food intake. To determine whether captopril caused animals to defend a lower body weight, animals in both groups were fasted for 24 h and subsequently restricted to 20% of their intake for 2 d. When free food was returned, captopril and control rats returned to their respective body weights and elicited comparable hyperphagic responses. These results suggest that angiotensin-converting enzyme inhibition protects against the development of diet-induced obesity and glucose intolerance.

Ghrelin and Metabolic Disorders

Ghrelin is a gut-brain peptide that has somatotropic, food intake increasing and adipogenic effects. Ghrelin is involved in modulating insulin and glucose metabolism in rodents according to recent studies. In humans acylated ghrelin reduces insulin sensitivity while unacylated ghrelin has opposite effects. In general, ghrelin seems to have diabetogenic effects. Obese, in particular abdominally obese, subjects have low ghrelin levels and decreased total ghrelin levels have been associated with metabolic syndrome and Type 2 diabetes. Most of the human studies in Type 1 diabetes have reported low ghrelin levels probably as a compensatory mechanism against hyperglycaemia. The data on obestatin in the regulation of energy balance is extremely contradictory. Interestingly, ghrelin receptor antagonists may improve glucose tolerance in rats without inducing weight gain by increasing insulin secretion. Antagonism of ghrelin function to treat diabetes is thus a fascinating idea. This review concentrates on recent findings on the orexigenic peptide ghrelin and its derivatives in metabolic disorders with emphasis put on human studies.

An evaluation of glucose tolerance in essential hypertension.

PurposeThis study aimed to determine the impaired glucose tolerance and diabetes prevalence in patients with essential hypertension (HT) and to compare the developed microvascular complications of these groups.Materials and MethodsAn oral glucose tolerance test (OGTT) was performed on 338 essential hypertensive cases and glucose tolerances were classified according to ADA-2002 criteria.ResultsOf the 338 cases, 32 people had diabetes (DM, 9.46%), 78 people had glucose intolerance (IGT, 23.1%), and 228 people had only hypertension but not IGT and DM (67.4%). Both the mean ages of the DM group (56.9 ± 6.7 years, p = 0.002) and IGT group (56.3 ± 8.4 years, p = 0.003) were older than the mean age of the control group (51.1 ± 6.4 years). The risk of IGT development was found to be four times greater in male cases than female cases when compared to the control group (p = 0.004, add ratio = 4.194). There were no significant differences in the body mass indexes (BMI's), hypertension durations, and microvascular complications between the groups.ConclusionIn conclusion, the risk of IGT and DM development in hypertensive cases increases with aging and longer hypertension duration. The risk of IGT development in hypertensive cases is four times more in males.

Nigella sativa inhibits intestinal glucose absorption and improves glucose tolerance in rats

Aim of the study Nigella sativa L. (Ranunculaceae) seeds have been used traditionally for centuries, notably for treating diabetes. Materials and methods We studied the effects of the crude aqueous extract of Nigella sativa seeds on intestinal glucose absorption in vitro using a short-circuit current technique and in vivo using an oral glucose tolerance test. Results The aqueous extract of Nigella sativa (0.1 pg/ml to 100 ng/ml) exerted dose-dependent inhibition of sodium-dependent glucose transport across isolated rat jejunum. Maximal inhibition exceeded 80% and IC 50 was close to 10 pg/ml. An oral glucose tolerance test was carried out in rats after the initial dose and after a 6-week treatment of Nigella sativa (2 g/(kg day)), and compared to metformin (300 mg/(kg day)). Chronic Nigella sativa treatment improved glucose tolerance as efficiently as metformin. Nigella sativa and metformin also reduced body weight without any toxic effect. Conclusions To our knowledge, this is the first demonstration that Nigella sativa directly inhibits the electrogenic intestinal absorption of glucose in vitro. Together with the observed improvement of glucose tolerance and body weight in rats after chronic oral administration in vivo, these effects further validate the traditional use of Nigella sativa seeds against diabetes.

Atypical antipsychotic drugs induce derangements in glucose homeostasis by acutely increasing glucagon secretion and hepatic glucose output in the rat

Use of the second-generation antipsychotic drugs (SGAs) results in the development of obesity and a type 2 diabetes-like syndrome. We hypothesised that, in addition to the insulin resistance associated with the obesity, the SGAs might have acute effects on glucose metabolism that could contribute to the derangements in glucose metabolism. We investigated the effects of therapeutically relevant levels of three different antipsychotic medications (haloperidol, quetiapine and clozapine) on glucose tolerance, measures of insulin resistance and hepatic glucose production, and on insulin and glucagon secretion in rats. We found that these drugs induce impaired glucose tolerance in rats that is associated with increased insulin secretion (clozapine>quetiapine>haloperidol) but is independent of weight gain. However, Akt/protein kinase B activation is normal, and at these levels of drug there was no effect on insulin action in fat cells or soleus muscle, and no effect on insulin sensitivity as evaluated by insulin tolerance tests. We show that clozapine induces increased glucose levels following pyruvate and glycerol challenges, indicating an increase in hepatic glucose output (HGO). Increased HGO would in turn increase insulin release and would explain the apparent phenotype mimicking insulin resistance. We provide evidence that this effect could at least in part be mediated by a stimulation of glucagon secretion. Our findings indicate that SGAs can cause acute derangements in glucose metabolism that are not caused by a direct induction of insulin resistance but act via an increase in glucagon secretion and thus stimulation of hepatic glucose production.

Differential effects of diets rich in medium- versus long chain triacylglycerols on muscular lipid and acylcarnitine content do not affect glucose tolerance in rats

Differential effects of diets rich in medium- versus long chain triacylglycerols on muscular lipid and acylcarnitine content do not affect glucose tolerance in rats

The opposing effects of the flavonoids isoquercitrin and Sissotrin, isolated from Pterospartum tridentatum, on oral glucose tolerance in rats

The effect of an aqueous extract of Pterospartum tridentatum on the blood glucose levels of normal Wistar rats was investigated in a situation of oral glucose challenge. The extract at 300 mg/kg showed an antihyperglycaemic effect in the first 30 min after glucose challenge but then the blood glucose levels rose above those of the control group, indicating the presence of compounds with different effects on glucose tolerance. Nine compounds of isoflavone and flavonol skeletons were identified in the extract by HPLC-ESI-MS(n), four of them being identified for the first time in this species. The isoflavone sissotrin and the flavonol derivative, isoquercitrin, were selected for the oral glucose tolerance test. Isoquercitrin (100 mg/kg) showed time-dependent antihyperglycaemic activity by delaying the post-oral glucose load glycaemic peak at 30 min, as did the sodium-dependent glucose transporter inhibitor phloridzin (100 mg/kg). In contrast, sissotrin (100 mg/kg) showed an opposite effect, impairing glucose tolerance. In conclusion, these preliminary results indicate that the effect of the extract on blood glucose may be either antihyperglycaemic or hyperglycaemic. Additionally, as far as is known, these are the first in vivo results on the acute antihyperglycaemic potential of isoquercitrin.

Insulin hypersensitivity in mice lacking the V1b vasopressin receptor

We have reported that [Arg(8)]-vasopressin-stimulated insulin release is blunted in islet cells isolated from V1b receptor-deficient (V1bR(-/-)) mice. In this study, we used V1bR(-/-) mice to examine the physiological role of the V1b receptor in regulating blood glucose levels in vivo, and we found that the fasting plasma glucose, insulin and glucagon levels were lower in V1bR(-/-) mice than in wild-type (V1bR(+/+)) mice. Next, we evaluated glucose tolerance by performing an intraperitoneal glucose tolerance test (GTT). The plasma glucose and insulin levels during the GTT were lower in V1bR(-/-) mice than in V1bR(+/+) mice. An insulin tolerance test (ITT) revealed that, after insulin administration, plasma glucose levels were lower in V1bR(-/-) mice than in V1bR(+/+) mice. In addition, a hyperinsulinaemic-euglycaemic clamp study showed that the glucose infusion rate was increased in V1bR(-/-) mice, indicating that insulin sensitivity was enhanced at the in vivo level in V1bR(-/-) mice. Furthermore, we found that the V1b receptor was expressed in white adipose tissue and that insulin-stimulated phosphorylation of Akt as an important signaling molecule was increased in adipocytes isolated from V1bR(-/-) mice. Thus, the blockade of the V1b receptor could result, at least in part, in enhanced insulin sensitivity by altering insulin signalling in adipocytes.

Proposal open for discussion: defining agreed diagnostic procedures in experimental diabetes research

Background Animal experimentation has a long tradition in diabetes research and has provided invaluable benefits with regard to insulin discovery and treatment assessment. Methods The review focuses on chemical-induced diabetes in rats and surveys the protocols of diabetes induction, diabetes diagnosis, and glucose tolerance evaluation in a selection of recent research. Results This brief review of techniques in experimental diabetes highlights that there is no uniformity, whereas standardisation of procedures is desirable so that comparability will exist among experiments carried out in different settings. Conclusions On this basis, questions are put and standards are proposed. It would be a platform to promote the exchange of ideas through expert consultation about practical issues related to animal research and a basis on which standards can be set according to user requirements and animal respect.

Metabolic Impact of Switching Antipsychotic Therapy to Aripiprazole After Weight Gain

Switching antipsychotic regimen to agents with low weight gain potential has been suggested in patients who gain excessive weight on their antipsychotic therapy. In an open-label pilot study, we evaluated the metabolic and psychiatric efficacy of switching to aripiprazole in 15 (9 men, 6 women) outpatients with schizophrenia who had gained at least 10 kg on their previous antipsychotic regimen. Individuals had evaluation of glucose tolerance, insulin resistance (insulin suppression test), lipid concentrations, and psychiatric status before and after switching to aripiprazole for 4 months. A third of the individuals could not psychiatrically tolerate switching to aripiprazole. In the remaining individuals, psychiatric symptoms significantly improved with decline in Clinical Global Impression Scale (by 26%, P = 0.015) and Positive and Negative Syndrome Scale (by 22%, P = 0.023). Switching to aripiprazole did not alter weight or metabolic outcomes (fasting glucose, insulin resistance, and lipid concentrations) in the patients of whom 73% were insulin resistant and 47% had impaired or diabetic glucose tolerance at baseline. In conclusion, switching to aripiprazole alone does not ameliorate the highly prevalent metabolic abnormalities in the schizophrenia population who have gained weight on other second generation antipsychotic medications.

Glucagon-Like Peptide-1 (GLP-1) Receptors Expressed on Nerve Terminals in the Portal Vein Mediate the Effects of Endogenous GLP-1 on Glucose Tolerance in Rats

Glucagon-like peptide-1 (GLP-1) is an intestinal hormone that is secreted during meal absorption and is essential for normal glucose homeostasis. However, the relatively low plasma levels and rapid metabolism of GLP-1 raise questions as to whether direct endocrine action on target organs, such as islet cells, account for all of its effects on glucose tolerance. Recently, an alternative neural pathway initiated by sensors in the hepatic portal region has been proposed to mediate GLP-1 activity. We hypothesized that visceral afferent neurons in the portal bed express the GLP-1 receptor (GLP-1r) and regulate glucose tolerance. Consistent with this hypothesis, GLP-1r mRNA was present in the nodose ganglia, and nerve terminals innervating the portal vein contained the GLP-1r. Rats given an intraportal infusion of the GLP-1r antagonist, [des-His(1),Glu(9)] exendin-4, in a low dose, had glucose intolerance, with a 53% higher glucose excursion compared with a vehicle-infused control group. Infusion of [des-His(1),Glu(9)] exendin-4 at an identical rate into the jugular vein had no effect on glucose tolerance, demonstrating that this dose of GLP-1r antagonist did not affect blood glucose due to spillover into the systemic circulation. These studies demonstrate that GLP-1r are present on nerve terminals in the hepatic portal bed and that GLP-1 antagonism localized to this region impairs glucose tolerance. These data are consistent with an important component of neural mediation of GLP-1 action.

Impact of high-protein diets with either moderate or low carbohydrate on weight loss, body composition, blood pressure and glucose tolerance in rats

One approach to achieve weight loss and decrease both obesity and associated morbidities involves high-protein, low-carbohydrate (HPLC) diets. This study compares the impact on metabolic health of HPLC and high-protein, medium-carbohydrate (HPMC) diets offered to diet-induced obese (DIO) rats. Weanling male rats were fed either a 37 % fat diet (n 48) or stock pellets (n 12) for 22 weeks. Rats fed the 37 % fat diet accumulated more body fat (26.6 versus 14.8 % body weight, P < 0.001) compared with those on stock diet. The DIO rats had higher systolic blood pressure (+6.6 mmHg, P = 0.002), fasting insulin (+63 % P = 0.006) and areas under the glucose (+21 %, P < 0.001) and insulin (+81 %, P < 0.001) curves following an oral glucose tolerance test. DIO rats were then separated into four groups and offered for 8 weeks either: (1) the 37 % fat diet; (2) an HPLC or (3) HPMC diet; or (4) fed the 37 % fat diet to the intake of the HPMC group. Rats offered the 37 % fat or HPLC diets gained while those on HPMC lost body fat. Blood pressure was not altered by the dietary switch. Both HPLC and HPMC rats had lowered fasting insulin (P = 0.027) and improved homeostatic assessment (HOMA; P = 0.011) that was not different from those of stock animals. These improvements occurred despite differences in fat gain, and indicate that both weight loss and macronutrient intake can impact favourably on obesity-associated morbidities.

Normal Ovarian Structure and Function with Normal Glucose Tolerance in Girls with Early Treatment of Classic Congenital Adrenal Hyperplasia

Hyperandrogenism and hyperinsulinism have both been suggested as etiologic factors behind functional ovarian hyperandrogenism or polycystic ovary syndrome. Females with congenital adrenal hyperplasia provide a clinical model to evaluate the contribution of pre- and post-natal hyperandrogenism on ovarian structure and function. Study Objective To evaluate glucose tolerance, and structure and androgen production of the ovaries in young females with classic congenital adrenal hyperplasia. Design, Setting, Participants Cross-sectional study, including the enrollment of participants, ages 8 to 20 years, recruited from the pediatric endocrinology clinical program of a tertiary pediatric referral center. Interventions Ten participants had oral glucose tolerance testing, adrenal and ovarian androgen measurements, and pelvic ultrasound studies performed. Main Outcome Measures Presence of altered response to glucose challenge, ovarian hyperandrogenism, or presence of polycystic ovaries by ultrasound. Results Measurements of fasting blood glucose, post-challenge glucose, and insulin resistance were normal in this sample. There was no evidence of ovarian hyperandrogenism after adrenal suppression with dexamethasone. All participants had normal ovarian structure without evidence of polycystic ovaries. Conclusions Females with classic congenital adrenal hyperplasia (21-hydroxylase deficiency) and normal glucose tolerance appear to have normal ovarian structure and function during the peripubertal period.

Prevention of diet-induced obesity and impaired glucose tolerance in rats following administration of leptin to their mothers

Absence of leptin is known to disrupt the development of energy balance regulatory mechanisms. We investigated whether administration of leptin to normally nourished rats affects energy balance in their offspring. Leptin (2 mg.kg(-1).day(-1)) was administered from day 14 of pregnancy and throughout lactation. Male and female offspring were fed either on chow or on high-fat diets that elicited similar levels of obesity in the sexes from 6 wk to 15 mo of age. Treatment of the dams with leptin prevented diet-induced increases in the rate of weight gain, retroperitoneal fat pad weight, area under the intraperitoneal glucose tolerance curve, and fasting plasma insulin concentration in female offspring. In the male offspring, the diet-induced increase in weight gain was prevented and increased fat pad weight was reduced. Energy intake per rat was higher in response to the obesogenic diet in male offspring of saline-treated but not leptin-treated dams. A similar trend was seen in 3-mo-old female offspring. Energy expenditure at 3 mo of age was higher for a given body weight in female offspring of leptin-treated compared with saline-treated dams when these animals were fed on the obesogenic diet. A similar trend was seen for male rats fed on the obesogenic diet. Thus leptin levels during pregnancy and lactation can affect the development of energy balance regulatory systems in their offspring.

Blunted lipolysis and fatty acid oxidation during moderate exercise in HIV-infected subjects taking HAART

The protease inhibitor (PI) ritonavir (RTV) has been associated with elevated resting lipolytic rate, hyperlipidemia, and insulin resistance/glucose intolerance. The purpose of this study was to examine relationships between lipolysis and fatty acid (FA) oxidation during rest, moderate exercise and recovery, and measures of insulin sensitivity/glucose tolerance and fat redistribution in HIV-positive subjects taking RTV (n=12), HAART but no PI (n=10), and HIV-seronegative controls (n=10). Stable isotope tracers [1-(13)C]palmitate and [1,1,2,3,3-(2)H5]glycerol were continuously infused with blood and breath collection during 1-h rest, 70-min submaximal exercise (50% VO2 peak), and 1-h recovery. Body composition was evaluated using DEXA, MRI, and MRS, and 2-h oral glucose tolerance tests with insulin monitoring were used to evaluate glucose tolerance and insulin resistance. Lipolytic and FA oxidation rates were similar during rest and recovery in all groups; however, they were lower during moderate exercise in both HIV-infected groups [glycerol Ra: HIV+RTV 5.1+/-1.2 vs. HIV+no PI 5.9+/-2.8 vs. Control 7.4+/-2.2 micromol.kg fat-free mass (FFM)-1.min-1; palmitate oxidation: HIV+RTV 1.6+/-0.8 vs. HIV+no PI 1.6+/-0.8 vs. Control 2.5+/-1.7 micromol.kg FFM.min, P<0.01]. Fasting and orally-challenged glucose and insulin values were similar among groups. Lipolytic and FA oxidation rates were blunted during moderate exercise in HIV-positive subjects taking HAART. Lower FA oxidation during exercise was primarily due to impaired plasma FA oxidation, with a minor contribution from lower nonplasma FA oxidation. Regional differences in adipose tissue lipolysis during rest and moderate exercise may be important in HIV and warrant further study.

An adolescent with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common clinical condition that manifests during adolescence with menstrual irregularities, acne, and hirsutism. As these symptoms are frequently observed in healthy teenagers, it can be difficult to recognize PCOS. Establishment of hyperandrogenism, polycystic ovaries, and identifying a metabolic disorder are required for the management of PCOS in a teenager. The underlying defects in PCOS are still unclear; however, insulin resistance and the metabolic syndrome are common in both obese and non-obese PCOS patients, so that the evaluation of glucose tolerance is recommended. More than 50% of PCOS patients are overweight or obese, and will benefit from an increase in physical activity and weight loss. Metformin is a treatment option that requires further investigation before being recommended on a long-term basis.