Long-term ketogenic diet causes glucose intolerance and reduced β- and α-cell mass but no weight loss in mice

2014 ◽  
Vol 306 (5) ◽  
pp. E552-E558 ◽  
Author(s):  
Johanne H. Ellenbroek ◽  
Laura van Dijck ◽  
Hendrica A. Töns ◽  
Ton J. Rabelink ◽  
Françoise Carlotti ◽  
...  

High-fat, low-carbohydrate ketogenic diets (KD) are used for weight loss and for treatment of refractory epilepsy. Recently, short-time studies in rodents have shown that, besides their beneficial effect on body weight, KD lead to glucose intolerance and insulin resistance. However, the long-term effects on pancreatic endocrine cells are unknown. In this study we investigate the effects of long-term KD on glucose tolerance and β- and α-cell mass in mice. Despite an initial weight loss, KD did not result in weight loss after 22 wk. Plasma markers associated with dyslipidemia and inflammation (cholesterol, triglycerides, leptin, monocyte chemotactic protein-1, IL-1β, and IL-6) were increased, and KD-fed mice showed signs of hepatic steatosis after 22 wk of diet. Long-term KD resulted in glucose intolerance that was associated with insufficient insulin secretion from β-cells. After 22 wk, insulin-stimulated glucose uptake was reduced. A reduction in β-cell mass was observed in KD-fed mice together with an increased number of smaller islets. Also α-cell mass was markedly decreased, resulting in a lower α- to β-cell ratio. Our data show that long-term KD causes dyslipidemia, a proinflammatory state, signs of hepatic steatosis, glucose intolerance, and a reduction in β- and α-cell mass, but no weight loss. This indicates that long-term high-fat, low-carbohydrate KD lead to features that are also associated with the metabolic syndrome and an increased risk for type 2 diabetes in humans.

2018 ◽  
Vol 57 (4) ◽  
pp. 1301-1312 ◽  
Author(s):  
Fred Brouns

Abstract In the past, different types of diet with a generally low-carbohydrate content (< 50–< 20 g/day) have been promoted, for weight loss and diabetes, and the effectiveness of a very low dietary carbohydrate content has always been a matter of debate. A significant reduction in the amount of carbohydrates in the diet is usually accompanied by an increase in the amount of fat and to a lesser extent, also protein. Accordingly, using the term “low carb–high fat” (LCHF) diet is most appropriate. Low/very low intakes of carbohydrate food sources may impact on overall diet quality and long-term effects of such drastic diet changes remain at present unknown. This narrative review highlights recent metabolic and clinical outcomes of studies as well as practical feasibility of low LCHF diets. A few relevant observations are as follows: (1) any diet type resulting in reduced energy intake will result in weight loss and related favorable metabolic and functional changes; (2) short-term LCHF studies show both favorable and less desirable effects; (3) sustained adherence to a ketogenic LCHF diet appears to be difficult. A non-ketogenic diet supplying 100–150 g carbohydrate/day, under good control, may be more practical. (4) There is lack of data supporting long-term efficacy, safety and health benefits of LCHF diets. Any recommendation should be judged in this light. (5) Lifestyle intervention in people at high risk of developing type 2 diabetes, while maintaining a relative carbohydrate-rich diet, results in long-term prevention of progression to type 2 diabetes and is generally seen as safe.


2013 ◽  
Vol 305 (9) ◽  
pp. E1059-E1070 ◽  
Author(s):  
Maximilian Bielohuby ◽  
Stephanie Sisley ◽  
Darleen Sandoval ◽  
Nadja Herbach ◽  
Ayse Zengin ◽  
...  

Moderate low-carbohydrate/high-fat (LC-HF) diets are widely used to induce weight loss in overweight subjects, whereas extreme ketogenic LC-HF diets are used to treat neurological disorders like pediatric epilepsy. Usage of LC-HF diets for improvement of glucose metabolism is highly controversial; some studies suggest that LC-HF diets ameliorate glucose tolerance, whereas other investigations could not identify positive effects of these diets or reported impaired insulin sensitivity. Here, we investigate the effects of LC-HF diets on glucose and insulin metabolism in a well-characterized animal model. Male rats were fed isoenergetic or hypocaloric amounts of standard control diet, a high-protein “Atkins-style” LC-HF diet, or a low-protein, ketogenic, LC-HF diet. Both LC-HF diets induced lower fasting glucose and insulin levels associated with lower pancreatic β-cell volumes. However, dynamic challenge tests (oral and intraperitoneal glucose tolerance tests, insulin-tolerance tests, and hyperinsulinemic euglycemic clamps) revealed that LC-HF pair-fed rats exhibited impaired glucose tolerance and impaired hepatic and peripheral tissue insulin sensitivity, the latter potentially being mediated by elevated intramyocellular lipids. Adjusting visceral fat mass in LC-HF groups to that of controls by reducing the intake of LC-HF diets to 80% of the pair-fed groups did not prevent glucose intolerance. Taken together, these data show that lack of dietary carbohydrates leads to glucose intolerance and insulin resistance in rats despite causing a reduction in fasting glucose and insulin concentrations. Our results argue against a beneficial effect of LC-HF diets on glucose and insulin metabolism, at least under physiological conditions. Therefore, use of LC-HF diets for weight loss or other therapeutic purposes should be balanced against potentially harmful metabolic side effects.


Nutrients ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 979 ◽  
Author(s):  
Eun-Young Kwon ◽  
So Kim ◽  
Myung-Sook Choi

This current study aimed to elucidate the effects and possible underlying mechanisms of long-term supplementation with dietary luteolin (LU)-enriched artichoke leaf (AR) in high-fat diet (HFD)-induced obesity and its complications (e.g., dyslipidemia, insulin resistance, and non-alcoholic fatty liver disease) in C57BL/6N mice. The mice were fed a normal diet, an HFD, or an HFD plus AR or LU for 16 weeks. In the HFD-fed mice, AR decreased the adiposity and dyslipidemia by decreasing lipogenesis while increasing fatty acid oxidation, which contributed to better hepatic steatosis. LU also prevented adiposity and hepatic steatosis by suppressing lipogenesis while increasing biliary sterol excretion. Moreover, AR and LU prevented insulin sensitivity by decreasing the level of plasma gastric inhibitory polypeptide and activity of hepatic glucogenic enzymes, which may be linked to the lowering of inflammation as evidenced by the reduced plasma interleukin (IL)-6, IL-1β, and plasminogen activator inhibitor-1 levels. Although the anti-metabolic syndrome effects of AR and LU were similar, the anti-adiposity and anti-dyslipidemic effects of AR were more pronounced. These results in mice with diet-induced obesity suggest that long-term supplementation with AR can prevent adiposity and related metabolic disorders such as dyslipidemia, hepatic steatosis, insulin resistance, and inflammation.


2015 ◽  
Vol 308 (7) ◽  
pp. E573-E582 ◽  
Author(s):  
Rockann E. Mosser ◽  
Matthew F. Maulis ◽  
Valentine S. Moullé ◽  
Jennifer C. Dunn ◽  
Bethany A. Carboneau ◽  
...  

Both short- (1 wk) and long-term (2–12 mo) high-fat diet (HFD) studies reveal enhanced β-cell mass due to increased β-cell proliferation. β-Cell proliferation following HFD has been postulated to occur in response to insulin resistance; however, whether HFD can induce β-cell proliferation independent of insulin resistance has been controversial. To examine the kinetics of HFD-induced β-cell proliferation and its correlation with insulin resistance, we placed 8-wk-old male C57Bl/6J mice on HFD for different lengths of time and assayed the following: glucose tolerance, insulin secretion in response to glucose, insulin tolerance, β-cell mass, and β-cell proliferation. We found that β-cell proliferation was significantly increased after only 3 days of HFD feeding, weeks before an increase in β-cell mass or peripheral insulin resistance was detected. These results were confirmed by hyperinsulinemic euglycemic clamps and measurements of α-hydroxybutyrate, a plasma biomarker of insulin resistance in humans. An increase in expression of key islet-proliferative genes was found in isolated islets from 1-wk HFD-fed mice compared with chow diet (CD)-fed mice. These data indicate that short-term HFD feeding enhances β-cell proliferation before insulin resistance becomes apparent.


PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248065
Author(s):  
Keigo Taki ◽  
Hiroshi Takagi ◽  
Tomonori Hirose ◽  
Runan Sun ◽  
Hiroshi Yaginuma ◽  
...  

Excessive sodium salt (NaCl) or fat intake is associated with a variety of increased health risks. However, whether excessive NaCl intake accompanied by a high-fat diet (HFD) affects glucose metabolism has not been elucidated. In this study, C57BL/6J male mice were fed a normal chow diet (NCD), a NCD plus high-NaCl diet (NCD plus NaCl), a HFD, or a HFD plus high-NaCl diet (HFD plus NaCl) for 30 weeks. No significant differences in body weight gain, insulin sensitivity, and glucose tolerance were observed between NCD-fed and NCD plus NaCl-fed mice. In contrast, body and liver weights were decreased, but the weight of epididymal white adipose tissue was increased in HFD plus NaCl-fed compared to HFD-fed mice. HFD plus NaCl-fed mice had lower plasma glucose levels in an insulin tolerance test, and showed higher plasma glucose and lower plasma insulin levels in an intraperitoneal glucose tolerance test compared to HFD-fed mice. The β-cell area and number of islets were decreased in HFD plus NaCl-fed compared to HFD-fed mice. Increased Ki67-positive β-cells, and increased expression levels of Ki67, CyclinB1, and CyclinD1 mRNA in islets were observed in HFD-fed but not HFD plus NaCl-fed mice when compared to NCD-fed mice. Our data suggest that excessive NaCl intake accompanied by a HFD exacerbates glucose intolerance, with impairment in insulin secretion caused by the attenuation of expansion of β-cell mass in the pancreas.


2009 ◽  
Vol 90 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Grant D Brinkworth ◽  
Manny Noakes ◽  
Jonathan D Buckley ◽  
Jennifer B Keogh ◽  
Peter M Clifton

2013 ◽  
Vol 305 (1) ◽  
pp. E149-E159 ◽  
Author(s):  
Rachel E. Stamateris ◽  
Rohit B. Sharma ◽  
Douglas A. Hollern ◽  
Laura C. Alonso

Type 2 diabetes (T2D) is caused by relative insulin deficiency, due in part to reduced β-cell mass ( 11 , 62 ). Therapies aimed at expanding β-cell mass may be useful to treat T2D ( 14 ). Although feeding rodents a high-fat diet (HFD) for an extended period (3–6 mo) increases β-cell mass by inducing β-cell proliferation ( 16 , 20 , 53 , 54 ), evidence suggests that adult human β-cells may not meaningfully proliferate in response to obesity. The timing and identity of the earliest initiators of the rodent compensatory growth response, possible therapeutic targets to drive proliferation in refractory human β-cells, are not known. To develop a model to identify early drivers of β-cell proliferation, we studied mice during the first week of HFD exposure, determining the onset of proliferation in the context of diet-related physiological changes. Within the first week of HFD, mice consumed more kilocalories, gained weight and fat mass, and developed hyperglycemia, hyperinsulinemia, and glucose intolerance due to impaired insulin secretion. The β-cell proliferative response also began within the first week of HFD feeding. Intriguingly, β-cell proliferation increased before insulin resistance was detected. Cyclin D2 protein expression was increased in islets by day 7, suggesting it may be an early effector driving compensatory β-cell proliferation in mice. This study defines the time frame and physiology to identify novel upstream regulatory signals driving mouse β-cell mass expansion, in order to explore their efficacy, or reasons for inefficacy, in initiating human β-cell proliferation.


2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
Amy C Burke ◽  
Brian G Sutherland ◽  
Cynthia G Sawyez ◽  
Dawn E Telford ◽  
Joseph Umoh ◽  
...  

Previous studies demonstrated that addition of the citrus flavonoids naringenin or nobiletin to a high-fat diet prevented the development of many disorders linked to the metabolic syndrome. In the present study, we assessed the ability of intervention with nobiletin or naringenin to reverse pre-established obesity, insulin resistance, hepatic steatosis, dyslipidemia and attenuate atherogenesis. Ldlr-/- mice were fed chow or a high-fat, cholesterol-containing (HFHC) diet for 12 weeks. For an additional 12 weeks, the HFHC-fed mice: (1) continued on the HFHC diet or were transferred to (2) chow, (3) HFHC + 3% naringenin, or (4) HFHC + 0.3% nobiletin. Following rapid weight gain during HFHC-induction, intervention with naringenin or nobiletin stimulated weight loss, while maintaining caloric intake. Micro-CT imaging revealed flavonoid intervention reversed adipose tissue accumulation by 40-60% in both subcutaneous and visceral depots. At 12 weeks, the HFHC-fed mice were hyperinsulinemic (6-fold), which was accompanied by increased fasting plasma glucose. Intervention with either flavonoid normalized plasma insulin and glucose and corrected impaired insulin and glucose tolerance. The HFHC diet increased cholesterol within VLDL (10-fold) and LDL (6-fold), which was reduced (~50%) by either naringenin or nobiletin intervention. HFHC-induction significantly increased hepatic steatosis. Flavonoid intervention reduced hepatic cholesterol (>50%) and triglyceride (~20%) via increased expression of Pgc1a and Cpt1a and reduced expression of Srebp1c. HFHC-induction increased atherosclerotic lesion area (13-fold), which was increased a further 2.5-fold at 24 weeks. Flavonoid intervention modestly retarded lesion size progression (16-20%). As well, intervention with naringenin or nobiletin slowed the accumulation of aortic cholesterol (~30-45%) and reduced lesional necrotic area (~25%), suggesting improved lesion morphology. These studies demonstrate in mice with pre-existing metabolic dysregulation and atherosclerosis that intervention with naringenin or nobiletin reverses obesity, dyslipidemia, hepatic steatosis and insulin resistance, and modestly attenuates the progression of advanced atherosclerosis.


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