rifampin and Insulin-Resistance

We conducted a randomized, open, placebo-controlled crossover trial to investigate the effects of the pregnane X receptor (PXR) agonist rifampin on an oral glucose tolerance test (OGTT) in 12 healthy volunteers. The subjects were administered 600 mg rifampin or placebo once daily for 7 days, and OGTT was performed on the eighth day. The mean incremental glucose and insulin areas under the plasma concentration-time curves (AUC(incr)) increased by 192% (P = 0.008) and 45% (P = 0.031), respectively. The fasting glucose, insulin, and C-peptide, and the homeostasis model assessment for insulin resistance, were not affected. The glucose AUC(incr) during OGTT was significantly increased in rats after 4-day treatment with pregnenolone 16α-carbonitrile (PCN), an agonist of the rat PXR. The hepatic level of glucose transporter 2 (Glut2) mRNA was downregulated by PCN. In conclusion, both human and rat PXR agonists elicited postprandial hyperglycemia, suggesting a detrimental role of PXR activation on glucose tolerance.

Topics: Adult; Animals; C-Peptide; Cross-Over Studies; Down-Regulation; Female; Glucose Tolerance Test; Glucose Transporter Type 2; Humans; Insulin; Insulin Resistance; Liver; Male; Mice; Mice, Inbred C57BL; Postprandial Period; Pregnane X Receptor; Pregnenolone Carbonitrile; Primary Cell Culture; Rats; Rats, Sprague-Dawley; Receptors, Steroid; Rifampin

Prolonged treatment with rifampicin (RFP), a first-line antibacterial agent used in the treatment of drug-sensitive tuberculosis, may cause various side effects, including metabolic disorders. The nuclear factor (erythroid-derived 2)-like 2 (NFE2L2, also known as NRF2) plays an essential regulatory role in cellular adaptive responses to stresses via the antioxidant response element (ARE). Our previous studies discovered that NRF2 regulates the expression of CCAAT-enhancer-binding protein β (Cebpb) and peroxisome proliferator-activated receptor gamma (Pparg) in the process of adipogenesis. Here, we found that prolonged RFP treatment in adult male mice fed a high-fat diet developed insulin resistance, but reduced fat accumulation and decreased expression of multiple adipogenic genes in white adipose tissues. In 3 T3-L1 preadipocytes, RFP reduced the induction of Cebpb, Pparg and Cebpa at mRNA and protein levels in the early and/or later stage of hormonal cocktail-induced adipogenesis. Mechanistic investigations demonstrated that RFP inhibits NRF2-ARE luciferase reporter activity and expression of NRF2 downstream genes under normal culture condition and in the early stage of adipogenesis in 3 T3-L1 preadipocytes, suggesting that RFP can disturb adipogenic differentiation via NRF2-ARE interference. Taken together, we demonstrate a potential mechanism that RFP impairs adipose function by which RFP likely inhibits NRF2-ARE pathway and thereby interrupts its downstream adipogenic transcription network.

Topics: 3T3-L1 Cells; Adipocytes, White; Adipogenesis; Adipose Tissue, White; Adiposity; Animals; Antibiotics, Antitubercular; Antioxidant Response Elements; Diet, High-Fat; Disease Models, Animal; Insulin Resistance; Male; Mice; Mice, Inbred C57BL; NF-E2-Related Factor 2; Obesity; Rifampin; Signal Transduction; Transcription, Genetic

Over recent years, the link between obesity, metabolic syndrome and Hidradenitis suppurativa (HS) has been explored. It has been demonstrated that HS patients have a high prevalence of the metabolic syndrome and an increased frequency of insulin resistance. The objective of our study is to estimate the effectiveness of an oral supplementation based on myo-inositol (MI), folic acid and liposomal magnesium (Levigon. Twenty subjects with HS and an impaired glucose metabolism were enrolled. Group A: 10 subjects received for 6 months MI 2000 mg, liposomal magnesium and folic acid associated to topical antibiotic therapy (clindamycin gel 1%), systemic antibiotic therapy (clindamycin 300 mg b.i.d. and rifampicin 600 mg daily for 6 weeks) and a normocaloric diet group B: 10 subjects received topical and systemic antibiotic therapy associated to a normocaloric diet for 6 months.. After 6 months group A patients showed an average reduction of Sartorius Score from 38.3±7.75 to 27.3±13.53 (P value <0.04) while in the control group there was a reduction of the Sartorius from 38.4±7.88 to 31.1±8.02 (P value =0.55). Moreover in group A Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was significantly reduced from 2.43±0.35 to 2.1±0.31 (P<0.01) whereas in group B HOMA-IR did not significantly decrease (2.51±0.65 at T0 at 2.40±0.67 at T1).. Our study underlines the importance of the evaluation of metabolic profile in patients with HS. Moreover, it suggests that the supplementation of MI, folic acid and liposomal magnesium in HS can improve the efficacy of concomitant therapies and the metabolic profile.

Topics: Administration, Cutaneous; Administration, Oral; Anti-Bacterial Agents; Clindamycin; Dietary Supplements; Drug Combinations; Drug Therapy, Combination; Energy Intake; Folic Acid; Glucose Intolerance; Hidradenitis Suppurativa; Humans; Inositol; Insulin Resistance; Liposomes; Magnesium; Metabolic Syndrome; Prevalence; Rifampin; Severity of Illness Index