Influence of aprepitant on the pharmacodynamics and pharmacokinetics of gliclazide in rats and rabbits

Evaluating and predicting the correlations of hepatic concentration and pyrrole-protein adduction with hepatotoxicity induced by retrorsine based on pharmacokinetic/pharmacodynamic model

Retrosine (RTS) is a pyrrolozidine alkaloid and a known hepatotoxin that widely exist in nature. The mechanisms involved in toxic action of pyrrolizidine alkaloids need further investigation. The objective of the present study was to evaluate the correlation of RTS hepatotoxicity with hepatic RTS concentration and pyrrole-protein adduction. Mice were intragastrically treated with RTS alone or RTS and ketoconazole (KTZ) simultaneously. Sera and liver tissues were collected at various time points after administration, followed by the determination of changes in serum transaminase activity, hepatic RTS concentration and pyrrole-protein adduction. The correlation of RTS hepatotoxicity with hepatic RTS concentration and hepatic pyrrole-protein adduction were examined by use of Sigmoid-Emax PK/PD models. Dose-dependent hepatotoxicity, hepatic RTS concentration and pyrrole-protein adduction were observed in the animals, which could be modulated by co-treatment with KTZ. The fit parameters indicated pyrrole-protein adduction was more closely related with liver injury than hepatic RTS concentration. Similar correlation was observed in mice given low-dose of RTS for 4 consecutive days. RTS hepatotoxicity is correlated with hepatic pyrrole-protein adduction derived from RTS rather than hepatic RTS concentration. The observed protein modification would be a good indicator to predict the hepatoxicity of RTS at low dose.

Novel HNF1A gene mutation in maturity-onset diabetes of the young: A case report

BACKGROUND

Maturity-onset diabetes of the young 3 (MODY3), caused by mutations in the HNF1A gene, is the most common subtype of MODY. The diagnosis of MODY3 is critical because a low dose of sulfonylurea agents can achieve glucose control.

CASE SUMMARY

We describe a patient with MODY3 involving a novel splicing mutation, in whom low-dose gliclazide was sufficient to control clinically significant hyperglycemia. Sanger sequencing identified a splicing HNF1A mutation in 12q24 NM_000545.5 Intron5 c.1108-1G>A. Glycemic control has been maintained without insulin therapy for 28 mo after the diagnosis of diabetes.

CONCLUSION

This case report highlights a novel HNF1A gene mutation in MODY3 that is responsive to sulfonylurea therapy.

Gliclazide attenuates acetic acid-induced colitis via the modulation of PPARγ, NF-κB and MAPK signaling pathways

Ulcerative Colitis is a universal autoimmune disease with high incidence rates worldwide. It is characterized by the existence of many other concurrent immune-associated ailments, including diabetes. The used strategies for the management of this highly costing and complicated disease face great challenges. Therefore, the urge for new medication with fewer side effects and high efficacy is growing. The peroxisome proliferator-activated receptor-gamma (PPARγ) and nuclear factor Kappa-B (NF-κB) can be considered as crucial targets for the treatment of ulcerative colitis. Several studies reported the antioxidants, anti-inflammatory, and antiapoptotic actions of gliclazide and evaluated its cardioprotective and renoprotective effects. However, its impact on ulcerative colitis has never been investigated. This study delineated the effect of gliclazide administration on ulcerative colitis induced by acetic acid in rats and the underlying molecular mechanisms. Gliclazide (10 mg/kg; p.o) prominently decreased colon tissue injury as assessed by the histopathological analysis as well as myeloperoxidase, and intercellular adhesion molecule-1 levels. Gliclazide significantly alleviated the proinflammatory mediator, IL-6, promoted the anti-inflammatory cytokine, IL-10 and, withheld oxidative stress in the injured colon tissues. The protective effect of gliclazide was mediated through the upregulation of PPARγ and downregulation of NF-κB expression. The diminution of ulcerative colitis was also accompanied by an inhibition of the elevated activity and expression of mitogen-activated protein kinases and caspase-3 as assessed by Western blot and immunohistochemistry, respectively. Our findings spotlight, for the first time, the potential of the antidiabetic agent, gliclazide, to attenuate the experimentally induced ulcerative colitis. Therefore, gliclazide might be a propitious agent for the management of ulcerative colitis in diabetic patients.

HNF1A mutation in a Thai patient with maturity-onset diabetes of the young: A case report

BACKGROUND

Maturity-onset diabetes of the young (MODY) is the most common form of monogenic diabetes. The disease is transmitted in autosomal dominant mode and diabetes is usually diagnosed before age 25 year. MODY 3 is caused by mutation of hepatocyte nuclear factor (HNF) 1A genes and is the most common MODY subtype. Diagnosis of MODY 3 is crucial since glycemic control can be accomplished by very low dose of sulfonylurea. In this report we described a Thai MODY 3 patient who had excellence plasma glucose control by treating with glicazide 20 mg per day and insulin therapy can be discontinued.

CASE SUMMARY

A 31-year-old woman was diagnosed diabetes mellitus at 14 years old. The disease was transmitted from her grandmother and mother compatible with autosomal dominant inheritance. Sanger sequencing of proband’s DNA identified mutation of HNF1A at codon 203 which changed amino acid from arginine to cysteine (R203C). This mutation was carried only by family members who have diabetes. The patient has been treated effectively with a combination of oral hypoglycemic agents and must include a very low dose of glicazide (20 mg/d). Insulin therapy was successfully discontinued.

CONCLUSION

We demonstrated a first case of pharmacogenetics in Thai MODY 3 patient. Our findings underscore the essential role of molecular genetics in diagnosis and guidance of appropriate treatment of diabetes mellitus in particular patient.

Sericin enhances the insulin-PI3K/AKT signaling pathway in the liver of a type 2 diabetes rat model

The aim of the current study was to investigate the regulatory effect of sericin on the hepatic insulin-phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway in a type 2 diabetes rat model. Male Sprague Dawley rats were randomly divided into four groups: Control group, diabetic model group, high-dose sericin group and low-dose sericin group, with 12 rats in each group. Fasting blood glucose was detected by the glucose oxidase method, and hepatic glycogen was determined by periodic acid-Schiff staining. The morphology of the liver was observed by hematoxylin and eosin staining. Immunohistochemical staining, western blotting and reverse transcription-quantitative polymerase chain reaction were used to determine the protein and mRNA expression levels of insulin receptor (IR), IR substrate-1 (IRS-1), PI3K and AKT. Compared with the control group, the blood glucose of the diabetic model group was significantly increased (P<0.05). The glycogen content and the expression levels of IR, IRS-1, PI3K and AKT in the diabetic model group were significantly lower (P<0.05), and the liver morphological structure of the diabetic model group exhibited obvious pathological changes compared with the control group. Compared with the diabetic model group, the blood glucose of the high- and low-dose sericin groups was significantly reduced, while the glycogen content and the expression levels of IR, IRS-1, PI3K and AKT in the sericin treatment groups were significantly increased (P<0.05). Additionally, the liver pathological changes of high-dose and low-dose sericin groups were markedly reduced. Sericin may enhance the signaling transduction effect of insulin by upregulating the expression levels of key factors (IR, IRS-1, PI3K and AKT) in the liver insulin-PI3K/AKT signaling pathway, thus promoting glucose transport and liver glycogen synthesis, and further reducing blood glucose.