Donahuebruhn6341
GS-HNE, measured by mass spectrometry, was lower in the hearts of treatment-naïve Mrp1(-/-) versus WT mice (P less then 0.05). DOX treatment decreased GS-HNE in WT but not Mrp1(-/-) mice, so that GS-HNE was modestly but significantly higher in Mrp1(-/-) versus WT hearts after DOX. Expression of enzymes mediating GSH synthesis and antioxidant proteins did not differ between genotypes. Thus, despite elevated GSH levels in Mrp1(-/-) hearts, DOX induced significantly more injury in the nuclei of Mrp1(-/-) versus WT hearts.Doxorubicin (DOX), an effective cancer chemotherapeutic agent, induces dose-dependent cardiotoxicity, in part due to its ability to cause oxidative stress. We investigated the role of multidrug resistance-associated protein 1 (Mrp1/Abcc1) in DOX-induced cardiotoxicity in C57BL wild-type (WT) mice and their Mrp1 null (Mrp1(-/-)) littermates. Male mice were administered intraperitoneal DOX (3 or 2 mg/kg body weight) or saline twice a week for 3 weeks and examined 2 weeks after the last dose (protocol A total dose 18 mg/kg) or for 5 weeks, and mice were examined 48 hours and 2 weeks after the last dose (protocol B total dose 20 mg/kg). Chronic DOX induced body weight loss and hemotoxicity, adverse effects significantly exacerbated in Mrp1(-/-) versus WT mice. In the heart, significantly higher basal levels of glutathione (1.41-fold ± 0.27-fold) and glutathione disulfide (1.35-fold ± 0.16-fold) were detected in Mrp1(-/-) versus WT mice, and there were comparable decreases in the glutathione/glutathione disulfide ratio in WT and Mrp1(-/-) mice after DOX administration. Surprisingly, DOX induced comparable increases in 4-hydroxynonenal glutathione conjugate concentration in hearts from WT and Mrp1(-/-) mice. However, more DOX-induced apoptosis was detected in Mrp1(-/-) versus WT hearts (P less then 0.05) (protocol A), and cardiac function, assessed by measurement of fractional shortening and ejection fraction with echocardiography, was significantly decreased by DOX in Mrp1(-/-) versus WT mice (P less then 0.05; 95% confidence intervals of 20.0%-24.3% versus 23.7%-29.5% for fractional shortening, and 41.5%-48.4% versus 47.7%-56.7% for ejection fraction; protocol B). Together, these data indicate that Mrp1 protects the mouse heart against chronic DOX-induced cardiotoxicity.In α-chloralose anesthetized cats, we examined the role of opioid receptor (OR) subtypes (µ, κ, and δ) in tibial nerve stimulation (TNS)-induced inhibition of bladder overactivity elicited by intravesical infusion of 0.25% acetic acid (AA). The sensitivity of TNS inhibition to cumulative i.v. doses of selective OR antagonists (cyprodime for µ, nor-binaltorphimine for κ, or naltrindole for δ ORs) was tested. Naloxone (1 mg/kg, i.v., an antagonist for µ, κ, and δ ORs) was administered at the end of each experiment. AA caused bladder overactivity and significantly (P less then 0.01) reduced bladder capacity to 21.1% ± 2.6% of the saline control. TNS at 2 or 4 times threshold (T) intensity for inducing toe movement significantly (P less then 0.01) restored bladder capacity to 52.9% ± 3.6% or 57.4% ± 4.6% of control, respectively. Cyprodime (0.3-1.0 mg/kg) completely removed TNS inhibition without changing AA control capacity. Nor-binaltorphimine (3-10 mg/kg) also completely reversed TNS inhibition and significantly (P less then 0.05) increased AA control capacity. Naltrindole (1-10 mg/kg) reduced (P less then 0.05) TNS inhibition but significantly (P less then 0.05) increased AA control capacity. Naloxone (1 mg/kg) had no effect in cyprodime pretreated cats, but it reversed the nor-binaltorphimine-induced increase in bladder capacity and eliminated the TNS inhibition remaining in naltrindole pretreated cats. These results indicate a major role of µ and κ ORs in TNS inhibition, whereas δ ORs play a minor role. Meanwhile, κ and δ ORs also have an excitatory role in irritation-induced bladder overactivity.6-Acetyl-8-cyclopentyl-5-methyl-2-([5-(piperazin-1-yl)pyridin-2-yl]amino)pyrido(2,3-d)pyrimidin-7(8H)-one [palbociclib (PD-0332991)] is a cyclin-dependent kinase 4/6 inhibitor approved for the treatment of metastatic breast cancer and is currently undergoing clinical trials for many solid tumors. Glioblastoma (GBM) is the most common primary brain tumor in adults and has limited treatment options. learn more The cyclin-dependent kinase 4/6 pathway is commonly dysregulated in GBM and is a promising target in treating this devastating disease. The blood-brain barrier (BBB) limits the delivery of drugs to invasive regions of GBM, where the efflux transporters P-glycoprotein and breast cancer resistance protein can prevent treatments from reaching the tumor. The purpose of this study was to examine the mechanisms limiting the effectiveness of palbociclib therapy in an orthotopic xenograft model. The in vitro intracellular accumulation results demonstrated that palbociclib is a substrate for both P-glycoprotein and breast cancer resistance protein. In vivo studies in transgenic mice confirmed that efflux transport is responsible for the limited brain distribution of palbociclib. There was an ∼115-fold increase in brain exposure at steady state in the transporter deficient mice when compared with wild-type mice, and the efflux inhibitor elacridar significantly increased palbociclib brain distribution. Efficacy studies demonstrated that palbociclib is an effective therapy when GBM22 tumor cells are implanted in the flank, but ineffective in an orthotopic (intracranial) model. Moreover, doses designed to mimic brain exposure were ineffective in treating flank tumors. These results demonstrate that efflux transport in the BBB is involved in limiting the brain distribution of palbociclib and this has critical implications in determining effective dosing regimens of palbociclib therapy in the treatment of brain tumors.The prevalence of obesity has increased dramatically worldwide leading to increases in obesity-related complications, such as obesity-related glomerulopathy (ORG). Obesity is a state of chronic, low-grade inflammation, and increased inflammation in the adipose and kidney tissues has been shown to promote the progression of renal damage in obesity. Current therapeutic options for ORG are fairly limited and, as a result, we are seeing increased rates of progression to end-stage renal disease. link2 Chalcones are a class of naturally occurring compounds with various pharmacological properties. 1-(3,4-Dihydroxyphenyl)-3-(2-methoxyphenyl)prop-2-en-1-one (L2H17) is a chalcone that we have previously synthesized and found capable of inhibiting the lipopolysaccharide-induced inflammatory response in macrophages. In this study, we investigated L2H17's effect on obesity-induced renal injury using palmitic acid-induced mouse peritoneal macrophages and high fat diet-fed mice. Our results indicate that L2H17 protects against renal injury through the inhibition of the mitogen-activated protein kinase/nuclear factor κB pathways significantly by decreasing the expression of proinflammatory cytokines and cell adhesion molecules and improving kidney histology and pathology. These findings lead us to believe that L2H17, as an anti-inflammatory agent, can be a potential therapeutic option in treating ORG.Several prodrugs of the naturally occurring combretastatins have undergone extensive clinical evaluation as vascular targeting agents (VTAs). Their increased selectivity toward endothelial cells together with their innate ability to rapidly induce vascular shutdown and inhibit tumor growth at doses up to 10-fold less than the maximum tolerated dose led to the clinical evaluation of combretastatins as VTAs. Tubulin is well established as the molecular target of the combretastatins and the vast majority of its synthetic derivatives. Furthermore, tubulin is a highly validated molecular target of many direct anticancer agents routinely used as front-line chemotherapeutics. The unique vascular targeting properties of the combretastatins have somewhat overshadowed their development as direct anticancer agents and the delineation of the various cell death pathways and anticancer properties associated with such chemotherapeutics. Moreover, the ongoing clinical trial of OXi4503 (combretastatin-A1 diphosphate) together with preliminary preclinical evaluation for the treatment of refractory acute myelogenous leukemia has successfully highlighted both the indirect and direct anticancer properties of combretastatins. In this review, we discuss the development of the combretastatins from nature to the clinic. The various mechanisms underlying combretastatin-induced cell cycle arrest, mitotic catastrophe, cell death, and survival are also reviewed in an attempt to further enhance the clinical prospects of this unique class of VTAs.
To evaluate interictal, circulating sphingolipids in women migraineurs.
In the fasting state, serum samples were obtained pain-free from 88 women with episodic migraine (EM; n=52) and from controls (n=36). Sphingolipids were detected and quantified by high-performance liquid chromatography coupled with tandem mass spectrometry using multiple reaction monitoring. Multivariate logistic regression was used to examine the association between serum sphingolipids and EM odds. A recursive partitioning decision tree based on the serum concentrations of 10 sphingolipids was used to determine the presence or absence of EM in a subset of participants.
Total ceramide (EM 6,502.9 ng/mL vs controls 10,518.5 ng/mL; p<0.0001) and dihydroceramide (EM 39.3 ng/mL vs controls 63.1 ng/mL; p<0.0001) levels were decreased in those with EM as compared with controls. Using multivariate logistic regression, each SD increase in total ceramide (odds ratio [OR] 0.07; 95% confidence interval [CI] 0.02, 0.22; p<0.001) and total dihydroceramide (OR 0.05; 95% CI 0.01, 0.21; p<0.001) levels was associated with more than 92% reduced odds of migraine. Although crude sphingomyelin levels were not different in EM compared with controls, after adjustments, every SD increase in the sphingomyelin species C180 (OR 4.28; 95% CI 1.87, 9.81; p=0.001) and C181 (OR 2.93; 95% CI 1.55, 5.54; p=0.001) was associated with an increased odds of migraine. Recursive portioning models correctly classified 14 of 14 randomly selected participants as EM or control.
These results suggest that sphingolipid metabolism is altered in women with EM and that serum sphingolipid panels may have potential to differentiate EM presence or absence.
This study provides Class III evidence that serum sphingolipid panels accurately distinguish women with migraine from women without migraine.
This study provides Class III evidence that serum sphingolipid panels accurately distinguish women with migraine from women without migraine.
We aim to clarify the pathogenic role of intermediate size repeat expansions of SCA2, SCA3, SCA6, and SCA17 as risk factors for idiopathic Parkinson disease (PD).
We invited researchers from the Genetic Epidemiology of Parkinson's Disease Consortium to participate in the study. link3 There were 12,346 cases and 8,164 controls genotyped, for a total of 4 repeats within the SCA2, SCA3, SCA6, and SCA17 genes. Fixed- and random-effects models were used to estimate the summary risk estimates for the genes. We investigated between-study heterogeneity and heterogeneity between different ethnic populations.
We did not observe any definite pathogenic repeat expansions for SCA2, SCA3, SCA6, and SCA17 genes in patients with idiopathic PD from Caucasian and Asian populations. Furthermore, overall analysis did not reveal any significant association between intermediate repeats and PD. The effect estimates (odds ratio) ranged from 0.93 to 1.01 in the overall cohort for the SCA2, SCA3, SCA6, and SCA17 loci.
Our study did not support a major role for definite pathogenic repeat expansions in SCA2, SCA3, SCA6, and SCA17 genes for idiopathic PD.