Infants of diabetic mothers (IDM) are at increased risk for metabolic complications. Type 1 and some type 2 diabetic patients have elevated levels of ketone bodies acetoacetate (AA) and β-hydroxybutyrate (BHB).
The aim of this study is to examine how hyperketonemia in diabetic mothers affects markers of inflammation and oxidative stress in their offspring.
Blood was obtained from 23 diabetic mothers and 13 healthy mothers, and their infants’ umbilical cords at the delivery. IL-8, MCP-1 and protein carbonyl (protein oxidation) levels were determined by ELISA. U937 human monocyte cell culture was used to examine the effect of AA and BHB on secretion of MCP-1.
There was a significant increase in the levels of AA in cord blood of diabetic mothers compared with cord blood of healthy mothers. A significant increase in the levels of protein oxidation (p<0.05) and MCP-1 levels (p<0.05) were observed in the cord blood of IDMs. The level of MCP-1 significantly correlated (r=0.51, p=0.01) with the concentration of AA in the IDM. In further experiments with cultured monocytes treated with exogenous AA (0-4 mM), a significant increase in MCP-1 secretion was observed with AA but not in BHB-treated monocytes.
Blood levels of AA and MCP-1 are elevated in IDM, which may contribute to the development of the metabolic complications seen in IDM.
Infant of diabetic mother; Oxidative stress; MCP-1; acetoacetate; Hyperketonemia
Studies documented that platelet activating factor (PAF) and the enzyme platelet activating factor acetylhydrolase (PAFAH) play a very important role in the pathogenesis of neonatal necrotizing enterocolitis (NEC). In this retrospective, case-controlled pilot study, the authors investigated the prevalence of single nucleotide polymorphisms (Ile198Thr and Ala379Val) of the PAFAH gene.
Subjects and methods
We screened 570 blood samples from both Caucasian and African-American preterm infants in the Northwest Louisiana population for the above mentioned PAFAH gene polymorphisms. Out of 570 infants, 36 had stage I or II NEC based on diagnostic coding, the International Classification of Diseases, 9th revision, Clinical Modification, 2009 (ICD-9-CM). The remaining infants without an ICD-9-CM diagnosis of NEC were recruited as control population. The DNA was isolated and restriction fragment length polymorphism microplate polymerase chain reaction assay was performed.
Variants of the PAFAH gene polymorphism (Ile198Thr and Ala379Val) frequencies were not significantly different between the infants with NEC and the control group (P value of 0.26 by either multiple logistic regression analysis or the Cochran-Mantel-Haenszel test).
This is the first study of its kind in exploring the relationship between NEC and single nucleotide polymorphisms in the coding genes of the enzyme PAFAH. Our preliminary data demonstrated that adjusted for the effect of race, PAFAH polymorphisms (Ile198Thr and Ala379Val) have no significant effect on NEC.
Necrotizing enterocolitis; Neonates; Preterm; Single nucleotide polymorphisms; Platelet activating factor; PAF; PAF acetylhydrolase; PAFAH
Oxidative stress-induced decrease in tissue or systemic glutathione (GSH) and damage to the vascular endothelium of the blood-brain barrier such as occurs in diabetes or stroke will have important implications for brain homeostasis. Endothelial proliferation or repair is crucial to preserving barrier function. Cell proliferation has been associated with increased intracellular GSH, but the kinetic and distribution of GSH during cell cycle is poorly understood. Here, we determined the influence of cellular GSH status on the early dynamics of nuclear-to-cytosol (N-to-C) GSH distribution (6-h interval) during proliferation in a human brain microvascular endothelial cell line (IHEC). Control IHECs exhibited two peak S-phases of the cell cycle at 48 and 60 h post seeding that temporally corresponded to peak nuclear GSH levels and expression of cdk1, the S-to-G2-to-M checkpoint controller, suggesting a link between cell cycle progression and nuclear GSH. Sustained inhibition of GSH synthesis delayed S-to-G2/M cell transition; cell arrest in the S-phase was correlated with decreased total nuclear GSH and increased nuclear expressions of chk2/phospho-chk2 and GADPH. The temporal correspondence of nuclear chk2 activation and GAPDH expression with S-phase prolongation is consistent with enhanced DNA damage response and extended time for DNA repair. Strikingly, when GSH synthesis was restored, cell transit time through S-phase remained delayed. Significantly, total nuclear GSH remained depressed, indicating a time lag between restored cellular GSH synthetic capacity and recovery of the nuclear GSH status. Interestingly, despite a delay in cell cycle recovery, nuclear expressions of chk2/phospho-chk2 and GAPDH resembled those of control cells. This means that restoration of nuclear DNA integrity preceded normalization of the cell cycle. The current results provide important insights into GSH control of endothelial proliferation with implications for cell repair or wound healing in recovery post-oxidative damage.
► Increased nuclear-to-cytosol GSH was associated with brain endothelial cell (IHEC) cell cycle progression. ► Inhibition of GSH synthesis decreased nuclear GSH and delayed S-to-G2 transition. ► S-phase prolongation was linked to elevated DNA damage response. ► Recovery of nuclear GSH and normal cell cycle lagged behind the restoration of GSH synthesis.
GSH, glutathione; GSSG, glutathione disulfide; H1, histone H1; cdk1, cyclin dependent kinase 1; ATM, ataxia telangiectasia mutated; chk2, checkpoint kinase 2; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; Nuclear-to-cytosolic GSH distribution; GSH and endothelial proliferation; GSH and cell cycle; DNA damage response; Brain microvascular endothelial cells
To evaluate antitumor efficacy of the generic mTOR inhibitor sirolimus in preclinical animal models of head and neck squamous cell carcinoma (HNSCC) and compare its effects with those of the patented analog Temsirolimus.
In vivo study.
To develop xenograft established tumor model (ETM) of HNSCC, FaDu cells were injected subcutaneously into nude mice. When tumors reached 50–60mm3 mice were randomized into 5 groups and treated daily i.p. with sirolimus at various doses for 5 days a week for 3 weeks. Tumor volumes were measured. The results were compared with historical data on Temsirolimus effects. In the minimal residual disease (MRD) model surgical wounds were created and FaDu cells implanted. After 72h, animals were randomized into two groups and were injected i.p. with 0 or 5 mg/kg sirolimus for 5 days a week for one month.
In the ETM, sirolimus significantly inhibited tumor growth (p<0.01) although there was no overall significant difference in tumor growth inhibition between sirolimus and Temsirolimus. In the MRD model, sirolimus significantly suppressed growth of tumors (p<0.001) and improved survival compared with controls (p<0.01). There was a significant decrease in pS6 expression, indicating mTOR inhibition.
In this study we demonstrate that the generic mTOR inhibitor sirolimus shows potent antitumor activity in HNSCC and produces comparable effects to the patent drug Temsirolimus. Sirolimus has the potential of serving as an economic and comparative targeted agent to Temsirolimus in the treatment of HNSCC.
Level of Evidence
1b Individual randomized controlled trial.
sirolimus; Temsirolimus; head and neck squamous cell carcinoma
Adding posterolateral orbitotomy to pterional craniotomy allows greater exposure of the anterolateral skull base. However, there is a paucity of literature quantifying the relative benefit of adding posterolateral orbitotomy for various surgical targets. Our study is a step to address this issue. We performed dissections of five cadaveric heads (10 sides). The anterior communicating artery (A-Com) complex, posterior chiasm (anterior third ventricular region), ipsilateral optic canal, and ipsilateral supraclinoid internal carotid artery (ICA) bifurcation were chosen as targets. A pterional craniotomy was performed and the targets were morphometrically analyzed. Subsequently, posterolateral orbitotomy was done and analysis repeated. The field of view and measurements quantifying the angle of attack were compared. Addition of orbitotomy to pterional craniotomy increased the angle of exposure to ICA bifurcation, anterior third ventricular region, and A-Com complex by average of 15%, 29%, and 50%, respectively. Our study shows the addition of a posterolateral orbitotomy to the pterional craniotomy improves the angle of attack to the anterior third ventricular region and the A-Com complex, thus supporting the use of orbitopterional craniotomy for suprasellar lesions extending into anteroinferior third ventricle and A-Com aneurysms that point superiorly/posteriorly.
Pterional craniotomy; posterolateral orbitotomy; Morphometric; study
Diastolic dysfunction (DD) is associated with myocardial fibrosis mediated by inflammation. Higher levels of inflammation found in African Americans (AAs) may predict DD among asymptomatic individuals. We tested the hypothesis that high sensitivity C-reactive protein (hs-CRP), a biomarker of inflammation, is associated with DD in asymptomatic AAs.
We prospectively recruited 107 asymptomatic AAs without any history of cardiac, renal or inflammatory diseases or alcoholism. We measured hs-CRP and B-type Natriuretic peptide (BNP) levels and estimated left ventricular end diastolic pressure (LVEDP), mass and systolic function with echocardiography. Multivariate logistic regression analysis was used to define whether hs-CRP is an independent predictor of LVEDP.
Among 107 subjects: the mean age was 48±10 yrs, 58 (54%) were men, 59 (55%) had diabetes (DM), 48 (45%) had hypertension (HTN), the mean BMI was 30.5±4.8 and the mean ejection fraction was 63.1±5.8%. DD was present in 56(52%) subjects, 38 (36%) of whom also had a high LVEDP. On multivariate analysis, hs-CRP was independently associated with DD [odds ratio 3.36 (95% CI= 1.07 - 10.5, p = 0.04]. There was a 61% and 133% increase in the prevalence of any DD and DD with high LVEDP, respectively, between the lowest and the highest hs-CRP quartiles.
Diastolic dysfunction is prevalent among asymptomatic African Americans and it is independently associated with elevated level of hs-CRP, an inflammation marker.
Diastolic dysfunction; Inflammation; High sensitivity C-reactive protein; Biomarkers.
To determine if the mTOR inhibitor CCI-779 can sensitize head and neck squamous cell carcinoma (HNSCC) to radiotherapy (XRT) and compare the radiosensitizing effects to cisplatin with its known considerable toxicity.
Radiosensitizing effects of CCI-779 were assayed on HNSCC cell lines in vitro. CCI-779 (5mg/kg), cisplatin (1 mg/kg) and XRT (2 Gy) alone and in combination were evaluated for antitumor activity in mice bearing FaDu and SCC40 xenografts. Effects of CCI-779 on radiation-induced activation of the Akt/mTOR pathway were analyzed.
Although CCI-779 did not sensitize HNSCC cells to ionizing radiation in vitro, combination of CCI-779 and XRT significantly augmented the in vivo tumor growth inhibitory effects of XRT and CCI-779 (P<0.05). In addition CCI-779+XRT suppressed tumor growth more effectively than cisplatin+XRT (P<0.05). CCI-779+XRT significantly improved survival compared to XRT alone in both cisplatin-sensitive FaDu (P<0.01) and cisplatin-resistant SCC40 xenograft mice (P<0.05). There were no additional benefits of adding cisplatin to CCI-779+XRT. CCI-779 significantly attenuated irradiation-induced upregulation of the mTOR pathway, increased apoptosis and displayed potent antiangiogenic activity in FaDu xenografts that was further enhanced by its combination with radiotherapy (P<0.05) which may explain the mechanism of its selective radiosensitizing effects in vivo and not in vitro.
Antitumor activity of radiotherapy was enhanced when combined with CCI-779 in HNSCC xenograft model. CCI-779+XRT showed antitumor activity superior to conventional chemoradiotherapy with cisplatin. These results pave the way for clinical trials utilizing molecular targeted therapy with CCI-779 in combination with radiotherapy for HNSCC treatment.
rapamycin analogues; temsirolimus; mTOR; in vivo; apoptosis
This anatomic study evaluated the extent that a fronto-orbital osteotomy (FOO) added to a bilateral frontal craniotomy widened the exposure to the midline compartment of the anterior, middle, and posterior cranial fossae. The goal was to determine if osteotomy would significantly increase angles for two targets: the foramen magnum (FM) and anterior clinoid process (ACP). Stepwise dissections were performed on five cadaveric heads. A bilateral frontal craniotomy was made, followed by FOO. After the ethmoids were removed, the planum sphenoidale was drilled to enter the sphenoid sinus. Further drilling exposed the anterior clivus, which was drilled down to FM. Excellent exposure of the basilar artery, vertebral artery, and brain stem was achieved. With and without FOO, angles of exposure were measured for two targets: the ACP and FM. The angle of exposure after FOO increased markedly with an average gain of 76% for the ACP and of 80% for FM. Compared with a conventional bifrontal craniotomy, the addition of FOO increased the surgical exposure and minimized frontal lobe retraction for accessing lesions of the anterior, middle, and posterior cranial fossae.
Brain tumor; extended frontal approach; operative approach; skull base; skull base tumor
A better understanding of how human immunodeficiency virus (HIV) coinfection affects the course of hepatitis C virus (HCV) infection is required to select patients with HIV who would benefit from current HCV therapy. Between June 1996 and March 2000, HCV RNA levels were quantified for 1,279 patients at the Louisiana State University Health Sciences Center; 28 of these patients were coinfected with HIV. HCV loads were quantified by the Bayer branched-DNA assay with a lower limit of detection of 0.2 Meq/ml. We compared the median HCV RNA levels of for patients coinfected with HIV and HCV and patients infected only with HCV who were in the same age range (23 to 55 years). The median HCV load for the 28 patients coinfected with HCV and HIV (17.8 Meq/ml) was significantly greater (P < 0.05) than that for similarly aged patients infected only with HCV (6.1 Meq/ml). The HCV load did not correlate with age or sex for either group of patients. A significant (R = −0.4; P < 0.05) negative correlation was observed between HCV load and CD4 count in the coinfected group, for whom the CD4 counts at the time of HCV load analysis ranged from 6 to 1,773/mm3. The increased HCV load in patients coinfected with HCV and HIV compared to that in patients infected only with HCV and the inverse relationship of the HCV load to the CD4 count indicate that immunosuppression results in decreased control of HCV replication. In addition, we report significantly higher HCV loads among coinfected African Americans than Caucasians.