Increased generation of reactive oxygen species (ROS) in vascular diseases such as atherosclerosis, diabetes, chronic renal failure and preeclampsia readily leads to impaired endothelium-dependent relaxation and vascular injury. To counteract ROS- and electrophile-mediated injury, cells can induce a number of genes encoding phase II detoxifying enzymes and antioxidant proteins. A cis-acting transcriptional regulatory element, designated as antioxidant response element (ARE) or electrophile response element (EpRE), mediates the transcriptional activation of genes such as heme oxygenase-1, gamma-glutamylcysteine synthethase, thioredoxin reductase, glutathione-S-transferase and NAD(P)H:quinone oxidoreductase. Other antioxidant enzymes such as superoxide dismutase and catalase and non-enzymatic scavengers such as glutathione are also involved in scavenging ROS. Nuclear factor-erythroid 2-related factor 2 (Nrf2), a member of the Cap nno Collar family of basic region-leucine zipper (bZIP) transcription factors, plays an important role in ARE-mediated antioxidant gene expression. Kelch-like ECH-associated protein-1 (Keap1) normally sequesters Nrf2 in the cytoplasm in association with the actin cytoskeleton, but upon oxidation of cysteine residues Nrf2 dissociates from Keap1, translocates to the nucleus and binds to ARE sequences leading to transcriptional activation of antioxidant and phase II detoxifying genes. Protein kinase C (PKC), mitogen-activated protein kinases (MAPKs) and phosphotidylinositol 3-kinase (PI3K) have been implicated in the regulation of Nrf2/ARE signaling. We here review the evidence that the Nrf2/ARE signaling pathway plays an important role in vascular homeostasis and the defense of endothelial and smooth muscle cells against sustained oxidative stress associated with diseases such as atherosclerosis and preeclampsia.
Animals ; Antioxidants ; metabolism ; Atherosclerosis ; physiopathology ; Endothelial Cells ; metabolism ; Female ; Gene Expression Regulation ; Humans ; Muscle, Smooth, Vascular ; metabolism ; NF-E2-Related Factor 2 ; genetics ; physiology ; Oxidative Stress ; genetics ; physiology ; Pre-Eclampsia ; physiopathology ; Pregnancy ; Response Elements ; physiology ; Signal Transduction ; physiology

AIMTo pretreat sperm at various temperatures before exposure to human papillomavirus (HPV) 16 DNA fragments and to assess the efficiency of HPV carrier sperm to transfect cumulus cells.

METHODSCumulus cells from follicular aspirates were obtained, pooled and divided into culture dishes containing Sybr Gold-stained HPV DNA carrying sperm that were either pretreated at 4 degree C, 37 degree C or 40 degree C (n = 5). The cells were incubated in 5% CO(2) in air mixture at 37 degree C for 24 hours. The efficiency of sperm to take up fluorescent HPV DNA was determined at hour 0. After incubation, cumulus cell viability was assessed using the eosin method and the percentages of fluorescent cumulus cells determined.

RESULTSOver half of all the cumulus cells became fluorescent with the highest percentage in the 37 degree C group. Sperm pretreated at 4 degree C had the greatest amount of HPV DNA fragments. Total sperm motility was similar for the 3 pretreatment groups. There were no differences in cumulus viability among the groups.

CONCLUSIONSperm pretreated at 37 degree C transferred the greatest amount of fluorescent HPV DNA fragments to the cumulus cells. The HPV DNA was observed in the nuclear and cytoplasmic compartments. The data suggested the possibility of sperm as a vector for the transmission of HPV DNA to the cumulus cells surrounding ovulated oocytes, which might lead to early implantation failures.

DNA, Viral ; pharmacokinetics ; Humans ; Male ; Papillomaviridae ; genetics ; Spermatozoa ; physiology ; Temperature ; Transfection ; methods

Background: Insulin-treated patients with long duration of type 2 diabetes mellitus (T2DM) are at increased risk of ketoacidosis related to sodium-glucose co-transporter 2 inhibitor (SGLT2i). The extent of circulating ketone elevation in these patients remains unknown. We conducted this study to compare the serum ketone response between dapagliflozin, an SGLT2i, and sitagliptin, a dipeptidyl peptidase-4 inhibitor, among insulin-treated T2DM patients. Methods: This was a randomized, open-label, active comparator-controlled study involving 60 insulin-treated T2DM patients. Participants were randomized 1:1 for 24-week of dapagliflozin 10 mg daily or sitagliptin 100 mg daily. Serum β-hydroxybutyrate (BHB) levels were measured at baseline, 12 and 24 weeks after intervention. Comprehensive cardiometabolic assessments were performed with measurements of high-density lipoprotein cholesterol (HDL-C) cholesterol efflux capacity (CEC), vibration-controlled transient elastography and echocardiography. Results: Among these 60 insulin-treated participants (mean age 58.8 years, diabetes duration 18.2 years, glycosylated hemoglobin 8.87%), as compared with sitagliptin, serum BHB levels increased significantly after 24 weeks of dapagliflozin (P=0.045), with a median of 27% increase from baseline. Change in serum BHB levels correlated significantly with change in free fatty acid levels. Despite similar glucose lowering, dapagliflozin led to significant improvements in body weight (P=0.006), waist circumference (P=0.028), HDL-C (P=0.041), CEC (P=0.045), controlled attenuation parameter (P=0.007), and liver stiffness (P=0.022). Average E/e’, an echocardiographic index of left ventricular diastolic dysfunction, was also significantly lower at 24 weeks in participants treated with dapagliflozin (P=0.037). Conclusion Among insulin-treated T2DM patients with long diabetes duration, compared to sitagliptin, dapagliflozin modestly increased ketone levels and was associated with cardiometabolic benefits.