Effects of magnesium biotinate supplementation on serum insulin, glucose and lipid parameters along with liver protein levels of lipid metabolism in rats

2021 ◽  
Vol 34 (1) ◽  
pp. 9-19
Author(s):  
Kazim Sahin ◽  
Cemal Orhan ◽  
Osman Kucuk ◽  
Fusun Erten ◽  
Mehmet Tuzcu ◽  
...  
2020 ◽  
Author(s):  
Kazim Sahin ◽  
Cemal Orhan ◽  
Osman Kucuk ◽  
Fusun Erten ◽  
Mehmet Tuzcu ◽  
...  

Abstract Background: The objective of this study was to investigate the effects of a novel form of biotin (magnesium biotinate) on serum glucose, lipid profile, and hepatic lipid metabolism-related genes in rats. Methods: Forty-two rats were divided into six groups and fed a standard diet-based egg white powdered diet supplemented with either d-biotin at 0.01, 1 or 100 mg/kg BW or magnesium biotinate at 0.01, 1, or 100 mg/kg BW. Results: Serum total cholesterol and triglyceride decreased with biotin by both sources (P < 0.05). Concentrations were lower with magnesium biotinate when comparing the 1 mg/kg dose groups (P < 0.05). Serum, liver, and brain biotin, and liver cyclic guanosine monophosphate (cGMP) concentrations were greater when rats were treated with magnesium biotinate versus d-biotin, particularly when comparing the 1 mg/kg and 100 mg/kg dose groups (P < 0.05). Both forms of biotin decreased the liver SREBP‐1c and FAS and increased AMPK-α1, ACC-1, ACC-2, PCC, and MCC levels (P < 0.05). The magnitudes of responses were more emphasized with magnesium biotinate. Conclusions: Magnesium biotinate, compared with a commercial d-biotin, is more effective in reducing serum lipid concentrations and in regulating gene levels of intermediary metabolism-related biomarkers.


2008 ◽  
Vol 78 (2) ◽  
pp. 64-69 ◽  
Author(s):  
Choi ◽  
Cho

This study investigated the effect of vitamin B6 deficiency on the utilization and recuperation of stored fuel in physically trained rats. 48 rats were given either vitamin B6-deficient (B6–) diet or control (B6+) diet for 4 weeks and were trained on treadmill for 30 minutes daily. All animals were then subdivided into 3 groups: before-exercise (BE); during-exercise (DE); after-exercise (AE). The DE group was exercised on treadmill for 1 hour just before being sacrificed. Animals in the AE group were allowed to take a rest for 2 hours after being exercised like the DE group. Glucose and free fatty acids were compared in plasma. Glycogen and triglyceride were compared in liver and skeletal muscle. Protein levels were compared in plasma, liver, and skeletal muscle. Compared with the B6+ group, plasma glucose levels of the B6– group were significantly lower before and after exercise. Muscle glycogen levels of the B6– group were significantly lower than those of the B6+ group regardless of exercise. The liver glycogen level of the B6– group was also significantly lower than that of B6+ group during and after exercise. Before exercise, plasma free fatty acid levels were not significantly different between the B6+ and B6– groups, and plasma free fatty acid levels of the B6– group were significantly lower during and after exercise. The muscle triglyceride level of the B6– group was significantly lower than that of the B6+ group before exercise, and there were no differences between B6+ and B6– groups during and after exercise. Liver triglyceride levels were not significantly different between B6+ and B6– groups. Plasma protein levels of the B6– group were lower than those of B6+ before and after exercise. Muscle protein levels of the B6– group were not significantly different from those of the B6+ group. Liver protein levels of the B6– group were significantly lower than that of the B6+ group after exercise. Liver protein levels of both B6+ and B6– groups were not significantly changed, regardless of exercise. Thus, it is suggested that vitamin B6 deficiency may reduce fuel storage and utilization with exercise in physically trained rats.


1993 ◽  
Vol 128 (3) ◽  
pp. 251-258 ◽  
Author(s):  
Per H Andersen ◽  
Bjørn Richelsen ◽  
Jens Bak ◽  
Ole Schmitz ◽  
Niels S Sørensen ◽  
...  

In a short-term (eight days) double-blind crossover study involving 10 obese patients, the effects of dexfenfluramine on glucose and lipid metabolism were examined. The protocol comprised whole body in vivo measurements (hyperinsulinemic euglycemic clamp in combination with indirect calorimetry) and in vitro studies of isolated adipocytes (lipolysis and glucose transport). All study participants were weight stable during the study period (103.1±3.2, placebo vs 103.3±3.1 kg, dexfenfluramine, NS). The following parameters were significantly reduced after dexfenfluramine treatment: fasting levels of plasma glucose (6.2±0.2 vs 5.7±0.2 mmol/l, p<0.01), serum insulin (168.0±14.5 vs 138.9±7.9 pmol/l, p<0.05), serum C-peptide (0.68±0.03 vs 0.58±0.02 nmol/l, p<0.05) and total serum cholesterol (6.07±0.41 vs 5.48±0.38 mmol/l, p< 0.01). In the basal state glucose oxidation rate was significantly reduced by 36% (p<0.001), whereas non-oxidative glucose disposal was significantly increased by 41% (p<0.01), following dexfenfluramine treatment. Insulin-stimulated (2 mU·kg−1·min−1) glucose disposal rate tended to be increased (18%, p=0.10) after dexfenfluramine. In conclusion, dexfenfluramine possesses beneficial regulatory effects on glucose and lipid metabolism in non-diabetic obese patients, independently of weight loss.


2011 ◽  
Vol 23 (4) ◽  
pp. 520 ◽  
Author(s):  
Yun Liu ◽  
Hong Jiang ◽  
Ling-Yun He ◽  
Wu-Jian Huang ◽  
Xiao-Yu He ◽  
...  

Polycystic ovary syndrome (PCOS) may result from hypersensitivity to insulin, which is negatively regulated by uncoupling protein (UCP)-2. Because cholesterol side-chain cleavage enzyme (CYP11A1) is closely linked to PCOS, the expression of UCP-2 and CYP11A1 in ovarian tissues from PCOS patients was examined in the present study. Twelve PCOS patients with hyperandrogenaemia who underwent laparoscopic ovarian wedge resection and 12 age-matched control patients who underwent contralateral ovarian biopsy were enrolled in the study. UCP-2 expression in early stage (primordial, primary and secondary) and late stage (sinus and mature) follicles was examined using immunohistochemistry, whereas UCP-2 and CYP11A1 mRNA and protein levels in ovarian tissue were determined using quantitative reverse transcription–polymerase chain reaction and western blot analyses, respectively. UCP-2 expression increased significantly with follicular development in both control and PCOS tissue, with expression in early stage follicles from PCOS patients significantly greater than that in controls. In addition, both UCP-2 and CYP11A1mRNA and protein levels, mean fasting blood glucose concentrations and fasting serum insulin levels were significantly higher in PCOS patients compared with the control group. Finally, a significant correlation between UCP-2 and CYP11A1 expression was found in PCOS but not control patients. In conclusion, in PCOS patients, there was a correlation between UCP-2 and CYP11A1 expression, which was significantly higher than in the control group. These changes in UCP-2 and CYP11A1 expression may mediate follicle development in PCOS.


2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Stefano Spolitu ◽  
Lale Ozcan

Excessive glucagon receptor action in hepatocytes is a major contributing factor to type 2 diabetes (T2D). Accordingly, there has been great interest in developing glucagon receptor antagonists (GRAs) as a treatment for T2D. Although phase 2 clinical trials have shown that GRAs effectively lower blood glucose in T2D subjects, they increase plasma low density lipoprotein (LDL) cholesterol levels, which has presented a significant block to their development. In this context, recent studies have suggested that cholesterol and proprotein convertase subtilisin/kexin type 9 (PCSK9) levels can be regulated by fasting and perhaps glucagon, but in-depth mechanistic insight is lacking. In order to test the functional importance of hepatic glucagon action on lipid metabolism, we silenced glucagon receptor (GcgR) in obese mice using AAV8-H1-shGcgr to silence the receptor in hepatocytes. Consistent with previous reports, this treatment effectively lowered blood glucose in obese mice without a change in body weight. Moreover, GcgR silencing, like GRAs in humans, significantly increased plasma LDL cholesterol. In search for the mechanism, we found that inhibition of GcgR significantly lowered hepatic LDL-receptor protein levels and increased both hepatic PCSK9 and circulating PCSK9. To determine causation, we treated GcgR-silenced mice with a neutralizing monoclonal antibody against PCSK9 and found that this intervention restored hepatic LDL-receptor protein levels and prevented the increase in LDL cholesterol. Further mechanistic work revealed that GcgR silencing in hepatocytes did not increase Pcsk9 mRNA. Rather, blocking GcgR increased the half-life of PCSK9 protein by suppressing signalling through exchange protein activated by cAMP 1 (Epac1). In particular, the ability of GcgR silencing to increase PCSK9 and suppress LDL receptor protein levels was mimicked by hepatocytes lacking Epac1. Thus, GcgR signalling through Epac1 appears to have critical effects on processes that regulate cholesterol metabolism through PCSK9. These new findings have important implications for the lipid metabolism effects of hepatic glucagon signalling in both normal physiology and metabolic disease, and for the development of safer GRA-like drugs to treat T2D.


2017 ◽  
Vol 49 (10) ◽  
pp. 793-800 ◽  
Author(s):  
Guoqiang Fan ◽  
Yu Qiao ◽  
Shixing Gao ◽  
Jun Guo ◽  
Ruqian Zhao ◽  
...  

AbstractZinc alpha2 glycoprotein (ZAG) is a new type of adipokine involved in adipose tissue mobilization, however, little is known about its lipid metabolism effect in liver. Therefore, we investigated the effects of ZAG in the regulation of hepatic lipid accumulation. Mice were randomly divided into two groups; one was fed a normal diet and another was fed a high-fat diet for eight weeks to establish obesity model. After that, the normal diet group was divided into ND (injection of pcDNA3.1) and NDZ (injection of ZAG recombinant plasmid) and the high-fat diet group was divided into HF (injection of pcDNA3.1) and HFZ (injection of ZAG recombinant plasmid). The mice were weighed once per week and injected with plasmid once every three days for eight times. The results showed that body weight and hepatic TG content were decreased dramatically in HFZ group compared with HF group. The stearoyl-CoAdesaturase1 (SCD1) and Acyl-CoA Synthetase-1 (ACSS1) protein levels in HFZ group were significantly decreased. Furthermore, phosphorylated hormone sensitive lipase (P-HSL) was significantly higher in HFZ group. In HFZ group, hepatic fatty acid translocase (CD36) and fatty acids binding protein-1 (FABP1) protein levels were reduced. In addition, the expression of phosphorylated protein kinase A (PPKA) in HFZ group was higher than the HF group. Meanwhile, NDZ group showed significantly decreased body weight and increased P-HSL level though the hepatic TG content showed no significantly changes compared with the ND group. Therefore, we conclude that ZAG may be beneficial for preventing high-fat-diet-induced hepatic lipid metabolic disorders.


2008 ◽  
Vol 295 (5) ◽  
pp. R1376-R1384 ◽  
Author(s):  
Chikako Iemura-Inaba ◽  
Toshio Nishikimi ◽  
Kazumi Akimoto ◽  
Fumiki Yoshihara ◽  
Naoto Minamino ◽  
...  

We investigated the levels of adrenomedullin (AM) system during the process of preadipocyte differentiation and its role in lipid metabolism and cellular signaling mechanism in differentiated adipocytes. We cultured rat preadipocytes and measured the following during the process of differentiation: two molecular forms of AM in the culture medium using a specific immunoradiometric assay and gene expression of AM and its receptor component using RT-PCR analysis. In differentiated adipocytes, we measured the effects of AM on the intracellular cAMP level, lipolysis, glucose incorporation, and the protein levels. Two molecular forms of AM were secreted into the medium, and the AM-mature/AM-total ratio was increased after 6 days of differentiation. Cultured rat preadipocytes highly expressed the genes of AM and its receptor components at day 1, and they increased at day 10. Administration of AM to preadipocytes increased the number of Oil Red O-positive adipocytes and spectrophotometric absorbance of Oil Red O. AM dose dependently increased cAMP level and lipolysis, and its effect was blocked by CGRP(8-37). Isoproterenol increased lipolysis, and AM had additive effects on isoproterenol-induced lipolysis. KT5720 and U0126 significantly inhibited the AM-induced lipolysis, whereas KT5720, but not U0126, significantly inhibited the isoproterenol-induced lipolysis. AM increased glucose incorporation and its effect was blocked by wortmannin. Western blot analysis revealed that AM increased phospho PKA, ERK, and Akt. These results indicate that AM and its receptor component are highly expressed in cultured adipocytes and may play a role in lipid metabolism via a different signaling pathway.


Sign in / Sign up

Export Citation Format

Share Document