Glucose Response Area Research Articles

Sex specific effect of ATPase inhibitory factor 1 on body weight: studies in high fat diet induced obese mice and genetic association studies in humans

BackgroundBased on the metabolic effect of exogenous ATPase inhibitory factor 1 (IF1) on glucose metabolism, we tested whether IF1 treatment is effective in ameliorating weight gain and whether its effects are sex specific. MethodsHFD-fed C57BL/6 mice were treated with IF1 (5 mg/kg body weight, injected intraperitoneally). The underlying mechanisms of effect of IF1 on body weight were investigated in vitro and in vivo. Associations between genotypes of IF1 and obesity and relevant phenotype were further tested at the population level. ResultsChronic treatment with IF1 significantly decreased body weight gain by regulating food intake of HFD-fed male mice. IF1 activated the AKT/mTORC pathway and modulated the expression of appetite genes in the hypothalamus of HFD-fed male mice and its effect was confirmed in hypothalamic cell lines as well as hypothalamic primary cells. This required the interaction of IF1 with β-F1-ATPase on the plasma membrane of hypothalamic cells, which led to an increase in extracellular ATP production. In addition, IF1 treatment showed sympathetic nerve activation as measured by serum norepinephrine levels and UCP-1 expression in the subcutaneous fat of HFD-fed male mice. Notably, administration of recombinant IF1 to HFD-fed ovariectomized female mice showed remarkable reductions in food intake as well as body weight, which was not observed in wild-type 5-week female mice. Lastly, sex-specific genotype associations of IF1 with obesity prevalence and metabolic traits were demonstrated at the population level in humans. IF1 genetic variant (rs3767303) was significantly associated with lower prevalence of obesity and lower levels of body mass index, waist circumference, hemoglobin A1c, and glucose response area only in male participants. ConclusionIF1 is involved in weight regulation by controlling food intake and potentially sympathetic nerve activation in a sex-specific manner.

Enrichment of Biscuits with Matcha Green Tea Powder: Its Impact on Consumer Acceptability and Acute Metabolic Response.

Matcha green tea powder (MGTP) is made with finely ground green tea leaves that are rich in phytochemicals, most particularly catechins. Shortbread biscuits were enriched with MGTP and evaluated for consumer acceptability and potential functional health properties. Baking decreased the content of total catechins by 19% compared to dough, although epimerization increased the amount of (+)-gallocatechin gallate at the expense of other catechins such as (−)-epigallocatechin gallate. Consumer acceptability tests using a 9-point hedonic scale showed that consumers preferred enriched biscuits with low content of MGTP (2 g of MGTP 100 g−1 of flour), and an increase of sugar content did not significantly improve the acceptability of MGTP-enriched biscuits. Overall, enrichment of biscuits with MGTP did not significantly affect the postprandial glucose or triglyceride response (area under curve) compared to non-enriched biscuits consumed with water or MGTP drink. Enriching biscuits with Matcha green tea is acceptable to consumers, but may not bring significant postprandial effects.

Effects of abomasal infusion of nicotinic acid on responses to glucose and β-agonist challenges in underfed lactating cows

The objectives were to assess the use of nicotinic acid (NA) to chronically (i.e., 74 h) manipulate plasma nonesterified fatty acid (NEFA) concentrations in partially feed-restricted lactating cows, determine whether the reduction of plasma NEFA altered responses to i.v. glucose tolerance test (ivGTT) and whether NA would attenuate an acute lipolytic stimuli of a β-agonist challenge (ivBAC). Eight lactating dairy cows [244±31 d in milk; 696±63kg of body weight (BW)] were blocked by breed and body condition score (3.2±0.4) and randomly assigned to a sequence of 2 treatments in a crossover design. Treatments were 74-h continuous abomasal infusion of NA solution (3mg/h per kg of BW) as an antilipolytic agent to decrease plasma NEFA concentrations or the same volume of water (200mL/h), concomitant with partial feed restriction. From 0 to 74 h of each experimental period, cows were feed-restricted to 33% of the ad libitum intake recorded during the prior 5 d. An ivGTT (0.25g/kg of BW of glucose i.v.) and an ivBAC (4 nmol/kg of BW of isoproterenol hydrochloride, i.v.) were performed at 48 and 72 h, respectively. Intake was 24.1, 8.2, 8.0, and 8.0kg of dry matter/d before restriction, on d 1, 2 and 3, respectively. Nicotinic acid decreased plasma NEFA and increased insulin and glucose concentrations during feed restriction. Nicotinic acid also led to greater glucose and insulin response areas under the curve during ivGTT [glucose: 6,562 vs. 5,056 (mg/dL)×180 min; insulin: 6,042 vs. 2,502 (µIU/mL)×180 min] and ivBAC [glucose: 535 vs. 240 (mg/dL)×120 min; insulin: 1,283 vs. 222 (µIU/mL)×120 min], and enhanced NEFA area under the curve during ivBAC [45,521 vs. 22,862 (µEq/L)×120 min]. Milk, fat, and protein yields (29.1, 1.2, and 0.93kg on d −2, respectively) decreased to 17.9, 0.81, and 0.56kg for control, and 11.5, 0.54, and 0.39kg for NA on d 3, respectively. Nicotinic acid may have decreased production by inhibiting the supply of NEFA for energy and milk fat synthesis. Milk urea nitrogen was increased by NA on d 2 (12.8 vs. 19.1mg/dL) and d 3 (11.6 vs. 17.8mg/dL), probably due to a greater reliance on mobilized amino acids. Somatic cell count was increased by NA on d 3 (187 vs. 848 ×1,000 cells/mL). Patterns of glucose and insulin concentration observed during 74 h of NA infusion reflect a state of insulin resistance, which contrasts with shorter-term responses in nonlactating cows. Data suggest that long-term supraphysiological infusion of NA affected intermediary metabolism beyond antilipolysis and did not inhibit acute lipolytic stimuli of ivBAC.

Interaction of ingested leucine with glycine on insulin and glucose concentrations.

The majority of individual amino acids increase insulin and attenuate the plasma glucose response when ingested with glucose. Objective. To determine whether ingestion of two amino acids simultaneously, with glucose, would result in an additive effect. Leucine (Leu) and glycine (Gly) were chosen because they were two of the most potent glucose-lowering amino acids when given individually. Materials and Methods. Nine subjects received test items on four separate days. The first was a water control, then 25 g glucose, or Leu + Gly (1 mmol/kg fat-free mass each) ±25 g glucose, in random order. Glucose, insulin, and glucagon were measured frequently for 2.5 hours. Net areas were calculated. Results. The glucose area response decreased by 66%. The insulin area response increased by 24% after ingestion of Leu + Gly + glucose compared to ingestion of glucose alone. The decrease in glucose response was not additive; the increase in insulin response was far less than additive when compared to previously published individual amino acid results. The glucagon concentration remained unchanged. Conclusion. There is an interaction between Leu and Gly that results in a markedly attenuated glucose response. This occurred with a very modest increase in insulin response. Changes in glucagon response could not explain the results. The mechanism is unknown.

Postprandial plasma glucose response and gastrointestinal symptom severity in patients with diabetic gastroparesis.

Gastroparesis is a well-known diabetic complication. The pathogenesis is not fully understood. However, it is important to early diagnose these patients. This study evaluated the plasma glucose response after a test meal, and gastrointestinal (GI) symptom severity in patients with clinical suspicion of diabetic gastroparesis, and assessed its usefulness to predict gastroparesis. In all, 83 subjects with insulin-treated diabetes mellitus (DM) type 1 and 2 were included; 53 subjects had gastroparesis and 30 had normal gastric emptying determined by gastric scintigraphy. GI symptom severity during the preceding 2 weeks was evaluated with a validated questionnaire. The test meal consisted of 100 g meat, 40 g pasta, 150 g carrot, and 5 g oil. The subjects ingested the meal under fasting conditions, and plasma glucose was followed during 180 minutes. Patients with gastroparesis demonstrated a blunted plasma glucose response after a test meal versus patients with normal gastric emptying (P < .005), reflected by lower maximum increase in plasma glucose response and incremental area under the curve of the plasma glucose, but a similar time to the maximum plasma glucose level. All GI symptoms were more severe in patients with gastroparesis. GI symptom severity had the best discriminative value to identify patients with gastroparesis with an area under the receiver operating curve of 0.83 (optimal cutoff: sensitivity 87%, specificity 80%). Patients with diabetic gastroparesis have a blunted postprandial plasma glucose response. Combining this information with the presence of GI symptoms can help clinicians identify diabetic patients with gastroparesis.

Steroidal contraceptives: effect on carbohydrate metabolism in women without diabetes mellitus.

Many hormonal contraceptives have been associated with changes in carbohydrate metabolism. Alterations may include decreased glucose tolerance and increased insulin resistance, which are risk factors for Type 2 diabetes mellitus and cardiovascular disease. These issues have been raised primarily with contraceptives containing estrogen. To evaluate the effect of hormonal contraceptives on carbohydrate metabolism in healthy women and those at risk for diabetes due to overweight. In April 2014, we searched the computerized databases MEDLINE, POPLINE, CENTRAL, and LILACS for studies of hormonal contraceptives and carbohydrate metabolism. We also searched for clinical trials in ClinicalTrials.gov and ICTRP. The initial search also included EMBASE. All randomized controlled trials were considered if they examined carbohydrate metabolism in women without diabetes who used hormonal contraceptives for contraception. Comparisons could be a placebo, a non-hormonal contraceptive, or another hormonal contraceptive that differed in drug, dosage, or regimen. Interventions included at least three cycles. Outcomes included glucose and insulin measures. We assessed all titles and abstracts identified during the literature searches. The data were extracted and entered into RevMan. We wrote to researchers for missing data. For continuous variables, the mean difference (MD) was computed with 95% confidence interval (CI) using a fixed-effect model. For dichotomous outcomes, the Peto odds ratio with 95% CI was calculated. We found 31 trials that met the inclusion criteria. No new trials were eligible in 2014. Twenty-one trials compared combined oral contraceptives (COCs); others examined different COC regimens, progestin-only pills, injectables, a vaginal ring, and implants. None included a placebo. Of 34 comparisons, eight had any notable difference between the study groups in an outcome.Twelve trials studied desogestrel-containing COCs, and the few differences from levonorgestrel COCs were inconsistent. A meta-analysis of two studies showed the desogestrel group had a higher mean fasting glucose (MD 0.20; 95% CI 0.00 to 0.41). Where data could not be combined, single studies showed lower mean fasting glucose (MD -0.40; 95% CI -0.72 to -0.08) and higher means for two-hour glucose response (MD 1.08; 95% CI 0.45 to 1.71) and insulin area under the curve (AUC) (MD 20.30; 95% CI 4.24 to 36.36).Three trials examined the etonogestrel vaginal ring and one examined an etonogestrel implant. One trial showed the ring group had lower mean AUC insulin than the levonorgestrel-COC group (MD -204.51; 95% CI -389.64 to -19.38).Of eight trials of norethisterone preparations, five compared COCs and three compared injectables. In a COC trial, a norethisterone group had smaller mean change in glucose two-hour response than a levonorgestrel-COC group (MD -0.30; 95% CI -0.54 to -0.06). In an injectable study, a group using depot medroxyprogesterone acetate had higher means than the group using norethisterone enanthate for fasting glucose (MD 10.05; 95% CI 3.16 to 16.94), glucose two-hour response (MD 17.00; 95% CI 5.67 to 28.33), and fasting insulin (MD 3.40; 95% CI 2.07 to 4.73).Among five recent trials, two examined newer COCs with different estrogen types. One showed the group with nomegestrel acetate plus 17β-estradiol had lower means than the levonorgestrel group for incremental AUC glucose (MD -1.43; 95% CI -2.55 to -0.31) and glycosylated hemoglobin (HbA1c) (MD -0.10; 95% CI -0.18 to -0.02). Two trials compared extended versus conventional (cyclic) regimens. With a dienogest COC, an extended-use group had greater mean change in AUC glucose (MD 82.00; 95% CI 10.72 to 153.28). In a small trial using two levonorgestrel COCs, the lower-dose group showed smaller mean change in fasting glucose (MD -3.00; 95% CI -5.89 to -0.11), but the obese and normal weight women did not differ significantly. Current evidence suggests no major differences in carbohydrate metabolism between different hormonal contraceptives in women without diabetes. We cannot make strong statements due to having few studies that compared the same types of contraceptives. Many trials had small numbers of participants and some had large losses. Many of the earlier studies had limited reporting of methods.We still know very little about women at risk for metabolic problems due to being overweight. More than half of the trials had weight restrictions as inclusion criteria. Only one small trial stratified the groups by body mass index (obese versus normal).

Ingestion of leucine + glycine with glucose produces a partially additive effect on plasma glucose despite a less than additive effect on serum insulin (LB427)

Leucine (Leu) is well recognized to stimulate insulin secretion and to reduce the glucose rise when ingested with glucose. Glycine (Gly) reduces the glucose rise, but only weakly stimulates insulin secretion. We have shown that both were particularly potent in their ability to attenuate the glucose response to 25 g glucose. The current study was designed to determine whether the glucose‐attenuating effects would be even greater if Gly and Leu were ingested together with glucose.On 4 separate days, 9 healthy subjects were studied. Test meals were given at 0800 hr. Subjects received water only on day 1, followed by 25 g glucose only, Leu + Gly (1 mmol/kg fat free body mass each), or Leu + Gly with 25 g glucose, on subsequent days in random order. Serum/plasma glucose, insulin and glucagon were measured frequently thereafter for 2.5 hrs. Net areas under the curve were calculated.The glucose area response decreased by 77% (p&lt;0.02) after ingestion of Leu + Gly + glucose compared to ingestion of glucose alone. The insulin area response increased by only 24% (p&lt;0.05). When compared to our previously published data on the individual amino acids, the decrease in glucose response with Leu + Gly + glucose was partially additive. The increase in insulin response was less than additive. The glucagon response was considerably less than additive.Thus, there is a mechanistic interaction between Leu and Gly when ingested with glucose that results in a markedly attenuated glucose response. This occurred in the presence of an attenuated insulin response. Changes in glucagon response could not explain the results. Overall, the way in which ingested amino acids interact with each other and affect glucose metabolism is complex and not well understood.Grant Funding Source: Supported in part by Funds from the Department of Veterans Affairs

Ingestion of Leucine + Phenylalanine with Glucose Produces an Additive Effect on Serum Insulin but Less than Additive Effect on Plasma Glucose

Most individual amino acids stimulate insulin secretion and attenuate the plasma glucose response when ingested with glucose. We determined whether ingestion of two amino acids simultaneously with glucose would result in an additive effect on the glucose area response compared with ingestion of amino acids individually. Leucine and phenylalanine were chosen because they were two of the most potent glucose-lowering amino acids when given individually. Eight healthy subjects were studied on four separate days. Test meals were given at 0800. The first meal was a water control. Subjects then received 25 g glucose or leucine + phenylalanine (1 mmol/kg fat free body mass each) ±25 g glucose in random order. Glucose, insulin and glucagon were measured frequently for 2.5 hours thereafter. Net areas under the curves were calculated using the mean fasting value as baseline. The insulin response to leucine + phenylalanine was additive. In contrast, the decrease in glucose response to leucine + phenylalanine + glucose was less than additive compared to the individual amino acids ingested with glucose. Interestingly, the insulin response to the combination was largely due to the leucine component, whereas the glucose response was largely due to the phenylalanine component. Glucose was unchanged when leucine or phenylalanine, alone or in combination, was ingested without glucose. This trial is registered with ClinicalTrials.gov NCT01471509.

Concentrated Arabinoxylan in Wheat Bread Has Beneficial Effects as Rye Breads on Glucose and Changes in Gene Expressions in Insulin-Sensitive Tissues of Zucker Diabetic Fatty (ZDF) Rats

The health-promoting effects of dietary fiber may vary with content, structure, and composition in the diet. The aim was to study how low-fiber wheat bread (WB), wheat bread supplemented with wheat arabinoxylan (AX) or oat β-glucan (BG), whole meal rye bread (RM), and rye bread with kernels (RK) affected central parameters of glucose and lipid metabolism and gene changes of Zucker diabetic fatty rats. Blood glucose response areas after an oral glucose tolerance test were significantly lower after AX (mean ± SEM; 2117 ± 170 mmol/L·180 min), RM (1978 ± 206 mmol/L·180 min), and RK (2234 ± 262 mmol/L·180 min) breads than after WB (3586 ± 100 mmol/L·180 min; p < 0.0001). AX, RK, and RM changed expressions of adipose GAPDH, AMPK, FAS, SREBP-1c, and hepatic PCG-1α, whereas BG had similar effects as WB. Thus, arabinoxylan added to wheat bread had beneficial effects on glycemic control as whole grain rye bread in this animal model.

Leucine + phenylalanine modify the glucose and insulin response to glucose

We have shown that phenylalanine (Phe) or leucine (Leu), when ingested with glucose, reduced the glucose response. Leu increased, whereas Phe had little effect on the insulin response. We then were interested in whether the effects would be additive if Phe and Leu were ingested together with glucose. On 4 separate days, 8 healthy subjects were studied. Test meals were given at 0800. Subjects received water, or 25 g glucose, or Leu+Phe (1 mmol/kg fat free body mass each) ± 25 g glucose. Blood glucose, insulin and glucagon were measured frequently thereafter for 2.5 hrs. Net areas under the curve were calculated. The insulin area response increased by 77% (p&lt;0.05) and the glucose area response decreased by 66% (p&lt;0.05) after ingestion of glucose+Leu+Phe compared to ingestion of glucose alone. The insulin response to Leu+Phe was additive compared to previous results obtained when the individual amino acids (AA) were ingested with glucose. In contrast, the decrease in glucose response to Leu+Phe+glucose was less than additive compared to the individual AA ingested with glucose. Blood glucose was unchanged when Leu or Phe, alone or in combination, were ingested without glucose. Thus, ingestion of Leu+Phe with glucose produced an additive increase in insulin area response but a less than additive reduction in glucose area response in healthy subjects.

Noninvasive photoacoustic computed tomography of mouse brain metabolism in vivo

We have demonstrated the feasibility of imaging mouse brain metabolism using photoacoustic computed tomography (PACT), a fast, noninvasive and functional imaging modality with optical contrast and acoustic resolution. Brain responses to forepaw stimulations were imaged transdermally and transcranially. 2-NBDG, which diffuses well across the blood-brain-barrier, provided exogenous contrast for photoacoustic imaging of glucose response. Concurrently, hemoglobin provided endogenous contrast for photoacoustic imaging of hemodynamic response. Glucose and hemodynamic responses were quantitatively decoupled by using two-wavelength measurements. We found that glucose uptake and blood perfusion around the somatosensory region of the contralateral hemisphere were both increased by stimulations, indicating elevated neuron activity. While the glucose response area was more homogenous and confined within the somatosensory region, the hemodynamic response area had a clear vascular pattern and spread wider than the somatosensory region. Our results demonstrate that 2-NBDG-enhanced PACT is a promising tool for noninvasive studies of brain metabolism.

Cassia cinnamon supplementation before an oral glucose tolerance test in overweight or obese young women

ObjectiveThe purpose of this study was to compare the effects Cassia cinnamon and cellulose placebo on oral glucose tolerance test (OGTT) blood glucose (BG) and serum insulin (SI) values and the Matsuda insulin sensitivity index (Mat‐ISI) in young, healthy, overweight or obese and sedentary women.MethodsOn three separate days, 10 women (22.7 ± 4 years, BMI of 35.39 ± 5.36) reported for a fasted, venous blood draw. Participants consumed 5g of cellulose placebo or 5g of Cassia cinnamon bark. Three hours after the initial blood draw, the participants completed an OGTT by consuming a 75g glucose solution within 2 minutes. Venous blood draws were taken 30, 60, 90, and 120 minutes after OGTT to determine changes in BG and SI.ResultsThe maximum BG concentration following OGTT was significantly lower in the Cassia group, as compared to the placebo group (P = 0.025). The overall glucose response, glucose and insulin total area under the curve, and Mat‐ISI were not different between the two groups (P &gt; 0.05).ConclusionsA 5g dose of Cassia cinnamon may reduce maximum post‐OGTT BG and improve glucose tolerance but does not have a significant impact on post‐OGTT insulin response in overweight or obese and sedentary women.

Lysine ingestion markedly attenuates the glucose response to ingested glucose without a change in insulin response

Background:Ingested proteins are known to stimulate a rise in insulin and glucagon concentrations. In our effort to explain this effect, we have begun to measure the effect of individual amino acids. Objectives:The objectives were to determine the effect of lysine ingestion on insulin and glucagon concentrations and whether the effect is moderated by glucose ingestion. Design:Thirteen healthy subjects were studied on 4 occasions. Water, 25 g glucose, 1 mmol lysine/kg lean body mass, or lysine plus glucose was given on separate occasions at 0800 after a 12-h fast. Serum lysine, glucose, insulin, and glucagon were measured during a 2.5-h period. The amount of lysine provided was equivalent to that present in a 672-g (24-oz) steak. Results:Lysine ingestion resulted in an ≈3-fold increase in lysine concentration and in a small decrease in glucose concentration. When lysine was ingested with glucose, the 2.5-h glucose area response decreased by 44% (P < 0.02). Lysine alone increased the insulin area response modestly; the insulin increase when lysine was ingested with glucose was similar to that when only glucose was ingested. Lysine stimulated an increase in glucagon (P < 0.02), whereas glucose decreased glucagon. Conclusions:Lysine ingestion results in a small decrease in serum glucose and an increase in glucagon and insulin concentrations. Lysine ingested with glucose dramatically attenuated the glucose-stimulated glucose response, but there was no change in insulin response. Whether similar effects will be observed with more physiologic doses of lysine remains to be determined.

Leucine, when ingested with glucose, synergistically stimulates insulin secretion and lowers blood glucose

Our laboratory is interested in the metabolic effects of ingested proteins. As part of this research, we currently are investigating the metabolic effects of ingested individual amino acids. The objective of the current study was to determine whether leucine stimulates insulin and/or glucagon secretion and whether, when it is ingested with glucose, it modifies the glucose, insulin, or glucagon response. Thirteen healthy subjects (6 men and 7 women) were studied on 4 different occasions. Subjects were admitted to the special diagnostic and treatment unit after a 12-hour fast. They received test meals at 8:00 am. On the first occasion, they received water only. Thereafter, they received 25 g glucose or 1 mmol/kg lean body mass leucine or 1 mmol/kg lean body mass leucine plus 25 g glucose in random order. Serum leucine, glucose, insulin, glucagon, and α-amino nitrogen concentrations were measured at various times during a 2.5-hour period after ingestion of the test meal. The amount of leucine provided was equivalent to that present in a high-protein meal, that is, that approximately present in a 350-g steak. After leucine ingestion, the leucine concentration increased 7-fold; and the α-amino nitrogen concentration increased by 16%. Ingested leucine did not affect the serum glucose concentration. When leucine was ingested with glucose, it reduced the 2.5-hour glucose area response by 50%. Leucine, when ingested alone, increased the serum insulin area response modestly. However, it increased the insulin area response to glucose by an additional 66%; that is, it almost doubled the response. Ingested leucine stimulated an increase in glucagon. Ingested glucose decreased it. When ingested together, the net effect was essentially no change in glucagon area. In summary, leucine at a dose equivalent to that present in a high-protein meal, had little effect on serum glucose or insulin concentrations but did increase the glucagon concentration. When leucine was ingested with glucose, it attenuated the serum glucose response and strongly stimulated additional insulin secretion. Leucine also attenuated the decrease in glucagon expected when glucose alone is ingested. The data suggest that a rise in glucose concentration is necessary for leucine to stimulate significant insulin secretion. This in turn reduces the glucose response to ingested glucose.

Effect of orally administered isoleucine with and without glucose on insulin, glucagon and glucose concentrations in non-diabetic subjects

Summary Objective The objective of the present study was to determine the degree to which ingested isoleucine modified the glucose, insulin and glucagon responses to ingested glucose. Design Nine healthy subjects were studied on 4 separate occasions. Plasma isoleucine, glucose, insulin, glucagon, and total alpha amino nitrogen were measured at various times during a 2.5 h period after ingestion of isoleucine (1 mmol/kg lean body mass), 25 g glucose, isoleucine + glucose, or water alone, given in random order. Results Following isoleucine ingestion, the isoleucine concentration increased ∼24-fold. The glucose decreased, the insulin remained unchanged. When isoleucine was ingested with glucose the increase in isoleucine was less, insulin increased, and the maximum concentration was 43% higher than that following ingestion of glucose alone. The glucose concentration increase was less and it decreased more rapidly following isoleucine + glucose, compared to glucose alone. Consequently, the glucose area response was markedly attenuated (61%). Isoleucine had little effect on the glucagon concentration. Conclusion Isoleucine per se does not stimulate a rise in insulin and has little effect on glucagon but does decrease the glucose concentration. It synergizes with ingested glucose in stimulating insulin secretion and in decreasing the glucose response.

Effect of the LoBAG30 diet on blood glucose control in people with type 2 diabetes

In subjects with untreated type 2 diabetes, we previously determined that a weight-maintenance, non-ketogenic diet containing 30 % protein, 50 % fat and 20 % carbohydrate (30:50:20) decreased the percentage total glycohaemoglobin (%tGHb) by 2.2 % glycohaemoglobin over 5 weeks compared to a diet recommended for the American public (protein-fat-carbohydrate 15:30:55). Both the fasting and postprandial glucose were decreased. The objective of the present study was to determine if increasing the carbohydrate content from 20 to 30 % at the expense of fat would still provide a similar effect on %tGHb, fasting and postprandial glucose concentration. Eight men with untreated type 2 diabetes were studied over a 5-week period. Results at the beginning (standard diet) and end of the 5-week study were analysed. Body weight was stable. Fasting glucose concentration decreased by 40 %; 24 h glucose area response decreased by 45 %. Insulin did not change. Mean %tGHb decreased by 1.7 (from 10.8 to 9.1 %), and was still decreasing linearly at 5 weeks. In conclusion, a high-protein, 30 % carbohydrate diet could be a patient-empowering method of improving the hyperglycaemia of type 2 diabetes without pharmacologic intervention. Long-term effects and general applicability of this diet remain to be determined.

생식조성이 정상성인의 혈당반응에 미치는 영향

본 연구는 생식을 정상성인에게 섭취시켰을 때 혈당반응에 미치는 영향을 연구하고, 생식의 혈당지수를 구하여 당뇨병 환자의 혈당 조절식으로 이용가능성을 조사하기 위하여 시판중인 생식 4(ES, HS, BS, SS)종을 섭취 전, 섭취 후 120분 동안 15분 간격으로 채혈하여 혈당을 측정하였다. 생식섭취 후 혈당수치는 포도당 섭취시보다 전반적으로 낮게 나타났으며, ES는 15～75분, SS는 15～75분, HS는 15～45분, BS는 15분 후의 혈당이 포도당보다 유의적으로 낮게 나타났다. 식이 섭취 후 측정한 시간에 따른 혈당값을 이용하여 혈당반응 곡선의 면적을 구한 결과, 생식 섭취군은 포도당 섭취군보다 면적이 적은 것으로 나타났으며, 상기 면적을 이용하여 GI를 산출한 결과, ES는 43.1±12.6으로 Low GI(55이하) 범위에 속하였으며, 그 외 생식은 Medium GI(56～69) 범위에 속하였다. 생식의 소화, 흡수 형태를 알아보기 위하여 상기에서 구한 혈당반응곡선 면적을 일반적인 최고 혈당값 나타내는 시간인 30분을 전후로 하여 LAR(혈당상승기)과 RAR(혈당감소기)을 구한 결과, 생식은 혈당 상승과 감소를 완만하게 해주는 것으로 나타났으며, 생식섭취 후 최고 혈당값을 포도당을 섭취했을 때보다 유의적으로 감소 시켰으며, 최고 혈당값을 나타내는 시간은 생식 ES에서 연장되는 경향을 나타내었다. 위의 결과들을 종합해 볼 때, 생식의 섭취는 체내 당의 소화와 흡수 과정을 천천히 진행시키며, 식후 최고 혈당수치를 감소시켜 전반적인 혈당반응을 원만하게 하는 것으로 나타났으며, GL은 ES(14.1)이 가장 낮았으며 HS, BS, SS(19.2～19.5) 수준으로 GL 역시 낮은 수치를 나타내었다. 위의 연구결과 생식은 당뇨병 환자의 식후 혈당상승을 조절하여 유익한 영향을 미칠 수 있을 것으로 사료되며, 생식의 조성에 따라 그 효과는 차이를 보이며, 사용하는 당의 특징과 곡류군의 조성, 식이섬유의 종류, 과일소재의 첨가 등에 따라 달라지므로 추후 심화된 연구가 필요할 것이다.

Reduction of Plasma NEFA Concentration by Nicotinic Acid Enhances the Response to Insulin in Feed-Restricted Holstein Cows

The objective was to investigate the relationship between elevated plasma nonesterified fatty acid (NEFA) concentration and insulin resistance in Holstein cows. Six nonlactating, nongestating, ruminally cannulated Holstein cows were blocked by body condition score and randomly assigned to a sequence of 2 treatments in a crossover design. Cows were offered legume and grass hay ad libitum supplemented with minerals and vitamins and were allowed free access to water and a trace mineralized salt block. Mobilization of body reserves was stimulated by withdrawing forage for 48h before initiation of treatments. Treatments consisted of 11 hourly abomasal infusions of water (control) or nicotinic acid (NA; 6 mg/h per kg of body weight) as an antilipolytic agent. Infusions of NA decreased plasma NEFA concentration from 545μEq/L to approximately 100μEq/L within 2h after initiation of treatments, and differences were maintained throughout infusions. Intravenous glucose tolerance test was performed 8h after initiation of treatments and was followed by 3h of blood sampling. The reduction of plasma NEFA concentration led to significantly greater glucose clearance rate (1.9 vs. 1.2%/min) and to decreased glucose half-life (37 vs. 58min), time to reach basal concentration (81 vs. 114min) and glucose response area under the curve during 180min of sampling [6,942 vs. 10,085 (μIU/mL)×180 min]. Enhanced glucose clearance was achieved when plasma NEFA was reduced by NA, despite lower insulin concentration (70.0 vs. 97.9±13.4μIU/mL) and a tendency for smaller insulin response area under the curve during 180min of sampling [7,646 vs. 12,104±2,587 (μIU/mL)×180 min], reflecting an increased response to endogenous insulin. Based on literature, we do not expect NA to have altered glucose metabolism directly; therefore, this experiment demonstrates a cause and effect relationship between elevated NEFA and insulin resistance in Holstein cows.

활동적 생활습관과 복합운동이 인슐린 저항성에 미치는 영향

The aim of the current study was to examine the changes of body composition, insulin resistance, blood lipid profiles and inflammatory markers following to spontaneous or controlled exercise participation in Korean adults selected from the general population. Subjects with previous diagnosis of diabetes were divided into 2 groups based upon spontaneous exercise participation for using a cross-sectional approach as active group (n=16) and non-active group (n=16). Additionally, we analyzed the effects of a 12 week exercise intervention program by the comparison of between exercise group (n=12) and control group (n=12). We measured anthropometric factors (BMI, percent body fat, WHR, and abdominal fat area by CT scanning), BP, blood levels of glucose, lipid profiles, fibrinogen, CRP, leptin, HbA1c, PAI-1, HOMA, OGTT and physical fitness. Independent t-tests were used to assess differences between active and non-active groups. Additionally, 2-way repeated ANOVA for group and time was used to compare the changes after a 12 week exercise intervention program. Significance was accepted at p0.05. In cross sectional comparison, active group showed significantly (p0.05) lower in WHR, visceral fat area, VSR, blood levels of TG, HbA1c and CRP than non-active group. Active group had a lower trend for HOMA-IR than non-active group, and showed significantly (p0.05) lower in glucose response area of OGTT than non-active group. Exercise group showed a significant (p0.05) decrease in WHR and HOMA-IR whereas control group showed no changes. In these results, we confirmed that continuous and regular exercise participation has a positive effect on insulin resistance with the decrease of WHR, visceral fat area and blood level of TG. We think that the more long-term exercise intervention may be effective improvement on insulin resistance.

Glucose Tolerance and Insulin Response to Intravenous Glucose Load in Sheep Fed on Germinated Sorghum Grain

The glucose tolerance and pancreatic insulin secretion response to glucose in sheep fed on germinated sorghum grain where determined using an intravenous glucose load. Twelve male thin tail sheep ( an indonesian native sheep, 12 months-old and 14,8 kg average body weight) were divided randomly into sorghum grain-based (S), germinated sorghum grain-based (G) and maize grain based (C) diets. Sheep were maintained at the same daily intake levels of metabolizable energy and crude protein in the diets throughout the experimental period. After two months of the experimental conditions, each diet group was subjected to an intravenous glucose load experiment in which five doses of glucose (0, 10, 20, 40, and 80 mg/kg BW) were injected to estimated the rate of glucose removal from blood and the pancreatic insulin secretion response. For each sheep and each glucose load dose, the incremental blood serum glucose and insulin concentrations above pre-injection concentration were calculated as serum glucose and insulin response areas. At all glucose doses, sheep fed on S diet had a greater (p<0,05) glucose response area compared to those of sheep fed on G and C diets. Likewise at all glucose doses, the insulin response area was smaller (p<0.05) in sheep fed on S diet than in sheep fed on G and C diets. The glucose and insulin response areas in sheep fed on G and C diets differed slightly. It was concluded that the portion of maize grain in the ruminant ratio could be substituted by germinated sorghum grain.