Kenneth H. Young

Enhanced expression of cytokines and chemokines by blood monocytes to in vitro lipopolysaccharide stimulation are associated with hostility and severity of depressive symptoms in healthy women.

The current study investigated the relation of hostility and severity of depressive symptoms, separately and jointly, to the capacity of blood monocytes to secrete an array of cytokines when stimulated by bacterial lipopolysaccharide (LPS). Subjects were 44 healthy, non-smoking, premenopausal women (aged 23-49 years) not currently taking oral contraceptives. Data were collected during the follicular phase of the menstrual cycle. The Cook-Medley Hostility (Ho) scale and the Beck Depression Inventory (BDI) were used to assess hostility and severity of depressive symptoms, respectively. Dual-color flow cytometry was used to measure the total expression of interleukin (IL)-1alpha, IL-1beta, IL-8, tumor necrosis factor (TNF)-alpha, monocyte chemotactic protein (MCP)-1 and monocyte inflammatory protein (MIP)-1alpha in blood monocytes following 4 h in vitro LPS stimulation of whole blood. In analyses adjusting for age, body mass index (BMI), fasting cholesterol, alcohol use, race and 17beta-estradiol (E(2)), higher Ho scores were associated with greater LPS-stimulated expression of IL-1alpha (beta = 0.033, p = 0.02), IL-8 (beta = 0.046, p = 0.01) and IL-1beta (beta = 0.024, p = 0.06). Higher BDI scores were associated with greater expression of TNF-alpha (beta = 0.042, p = 0.02) and IL-8 (beta = 0.045, p = 0.04). The linear combination of Ho and BDI scores was significantly associated with IL-1beta (beta = 0.18, p = 0.057), IL-8 (beta = 0.36, p = 0.01), TNF-alpha (beta = 0.25, p = 0.03), and IL-1alpha (beta = 0.18, p < 0.07). Thus, in healthy women, these psychological risk factors, alone and in combination, induce a proinflammatory phenotype in circulating monocytes characterized by the up-regulation of proinflammatory cytokines, supporting the hypothesis that inflammation may be a key pathway whereby hostility and depressive symptoms contribute to atherosclerosis and subsequent coronary heart disease (CHD).

Radioprotection of the brain white matter by Mn(III) N-butoxyethylpyridylporphyrin-based superoxide dismutase mimic, MnTnBuOE-2-PyP5+

Cranial irradiation is a standard therapy for primary and metastatic brain tumors. A major drawback of radiotherapy (RT), however, is long-term cognitive loss that affects quality of life. Radiation-induced oxidative stress in normal brain tissue is thought to contribute to cognitive decline. We evaluated the effectiveness of a novel mimic of superoxide dismutase enzyme (SOD), MnTnBuOE-2-PyP5+(Mn(III) meso-tetrakis(N-n-butoxyethylpyridinium-2-yl)porphyrin), to provide long-term neuroprotection following 8 Gy of whole brain irradiation. Long-term RT damage can only be assessed by brain imaging and neurocognitive studies. C57BL/6J mice were treated with MnTnBuOE-2-PyP5+ before and after RT and evaluated three months later. At this time point, drug concentration in the brain was 25 nmol/L. Mice treated with MnTnBuOE-2-PyP5+/RT exhibited MRI evidence for myelin preservation in the corpus callosum compared with saline/RT treatment. Corpus callosum histology demonstrated a significant loss of axons in the saline/RT group that was rescued in the MnTnBuOE-2-PyP5+/RT group. In addition, the saline/RT groups exhibited deficits in motor proficiency as assessed by the rotorod test and running wheel tests. These deficits were ameliorated in groups treated with MnTnBuOE-2-PyP5+/RT. Our data demonstrate that MnTnBuOE-2-PyP5+ is neuroprotective for oxidative stress damage caused by radiation exposure. In addition, glioblastoma cells were not protected by MnTnBuOE-2-PyP5+ combination with radiation in vitro. Likewise, the combination of MnTnBuOE-2-PyP5+ with radiation inhibited tumor growth more than RT alone in flank tumors. In summary, MnTnBuOE-2-PyP5+ has dual activity as a neuroprotector and a tumor radiosensitizer. Thus, it is an attractive candidate for adjuvant therapy with RT in future studies with patients with brain cancer. Mol Cancer Ther; 14(1); 70–79. ©2014 AACR.

Novel Manganese-Porphyrin Superoxide Dismutase-Mimetic Widens the Therapeutic Margin in a Preclinical Head and Neck Cancer Model

PURPOSE To test the effects of a novel Mn porphyrin oxidative stress modifier, Mn(III) meso-tetrakis(N-n-butoxyethylpyridinium-2-yl)porphyrin (MnBuOE), for its radioprotective and radiosensitizing properties in normal tissue versus tumor, respectively. METHODS AND MATERIALS Murine oral mucosa and salivary glands were treated with a range of radiation doses with or without MnBuOE to establish the dose-effect curves for mucositis and xerostomia. Radiation injury was quantified by intravital near-infrared imaging of cathepsin activity, assessment of salivation, and histologic analysis. To evaluate effects of MnBuOE on the tumor radiation response, we administered the drug as an adjuvant to fractionated radiation of FaDu xenografts. Again, a range of radiation therapy (RT) doses was administered to establish the radiation dose-effect curve. The 50% tumor control dose values with or without MnBuOE and dose-modifying factor were determined. RESULTS MnBuOE protected normal tissue by reducing RT-mediated mucositis, xerostomia, and fibrosis. The dose-modifying factor for protection against xerostomia was 0.77. In contrast, MnBuOE increased tumor local control rates compared with controls. The dose-modifying factor, based on the ratio of 50% tumor control dose values, was 1.3. Immunohistochemistry showed that MnBuOE-treated tumors exhibited a significant influx of M1 tumor-associated macrophages, which provides mechanistic insight into its radiosensitizing effects in tumors. CONCLUSIONS MnBuOE widens the therapeutic margin by decreasing the dose of radiation required to control tumor, while increasing normal tissue resistance to RT-mediated injury. This is the first study to quantitatively demonstrate the magnitude of a single drugs ability to radioprotect normal tissue while radiosensitizing tumor.

Stress-induced changes in the expression of monocytic β2-integrins: The impact of arousal of negative affect and adrenergic responses to the Anger Recall Interview

Adhesion of circulating monocytes to the vascular endothelium is one of the earliest steps in the development of atherosclerosis. This leukocyte-to-endothelium interaction is mediated in part by beta2-integrins, a group of cell adhesion molecules that bind to endothelial ligands. Given the significance of this interaction to atherogenesis, we examined the effects of stress, operationalized as the arousal of negative affect (NA) and cardiovascular and catecholamine responses to the Anger Recall Interview (ARI), on the expression of LFA-1 (CD11a), Mac-1 (CD11b) and p150/95 (CD11c) on circulating monocytes (CD14+). Subjects were 173 healthy, nonsmoking men and women (60% men, 40% minorities, aged 18-49 year). Arousal of NA, cardiovascular responses (heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP]), circulating catecholamines (epinephrine [Epi], norepinephrine [Ne]) and beta2-integrin (CD11/CD18) expression were determined prior to and following the ARI. The principal findings were that the ARI, on average, induced a decrease in monocyte expression of beta2-integrins. However, after adjusting for age, sex, body mass index, exercise status, and baseline level of beta2-integrin expression, those individuals who showed the largest increases in NA, Ne and DBP during the ARI showed an increase in monocyte beta2-integrin expression. Thus, heightened psychological and physiological stress responses induced phenotypic changes in monocytic expression of beta2-integrins that are consistent with the role of monocytes/macrophages in vascular inflammation and increased risk of atherosclerotic cardiovascular disease.

Endothelial colony forming cells (ECFCs) as a model for studying effects of low-dose ionizing radiation: growth inhibition by a single dose.

Identification of measurable nontransient responses to low-dose radiation in human primary cell cultures remains a problem. To this end, circulating endothelial colony-forming (progenitor) cells (ECFCs) were examined as an experimental model. ECFCs were isolated from three cord blood donors. Cells were positive for endothelial cell markers and remained highly proliferative after long-term cryopreservation. A single dose of X-ray radiation (0.06–0.38 Gy) inhibited ECFC culture growth. This effect was evident at 48 hours and persisted up to 72 hr postirradiation. Such protracted cytostatic response of ECFCs to low-dose radiation suggests that ECFC primary cultures can be used to study low-dose radiation effects.

Subtype-Specific Radiation Response and Therapeutic Effect of FAS Death Receptor Modulation in Human Breast Cancer

Breast cancer is the most common malignancy diagnosed among women and represents a heterogeneous group of subtypes. Radiation therapy is a critical component of treatment for breast cancer patients. However, little is known about radiation response among these intrinsic subtypes. In previous studies, we identified a significant induction of FAS after irradiation in biologically favorable breast cancer patients and breast cancer cell lines. Here, we expanded our study and investigated radiation response in a mouse model of breast cancer. MCF7 (luminal), HCC1954 (HER2+) or SUM159 (basal) cells were implanted orthotopically into the dorsal mammary fat pad of nude mice. These mice were then treated with different doses of radiation to assess tumor growth control. We further investigated the therapeutic effect of FAS modulation by silencing FAS in radiation-responsive tumors and injecting FAS agonist antibody into radiation-resistant tumors. Exposure to radiation inhibited MCF7, and to a lesser extent HCC1954 tumor growth in a dose-dependent manner. In contrast, SUM159 tumors were resistant to radiation. The estimated TCD50 values were 19.3 Gy for MCF7 and 44.9 Gy for SUM159. Radiation induced FAS expression in MCF7 tumors, but not SUM159 tumors. We found that silencing of FAS did not negatively impact radiation response in MCF7 tumors, possibly due to compensation by other apoptotic pathways. On the other hand, FAS activating antibody in combination with radiation treatment delayed SUM159 and HCC1954 tumor growth. However, it did not reach statistical significance compared to radiation treatment alone. Our results suggest that there is intrinsic variation in radiation response among breast cancer subtypes. FAS activation concurrent with radiation slows tumor growth in the radiation-resistant subtypes, but the effect was not significant. Alternative subtype-specific modulators of radiation response are under investigation.

It is a sticky situation: Increased expression of β2 integrins on peripheral monocytes following arousal of negative affect and stress-induced cardiovascular and catecholamine increases

pressure (BP) and heart rate (HR) were assessed at 1-min intervals and mean levels were calculated for baseline and ARI. Forearm blood flow (FBF) was assessed using venous occlusion plethysmography. Forearm vascular resistance (FVR) was derived by the equation mean arterial pressure (MAP)/FBF. We performed dual-color flow cytometry to determine expression of LPS-stimulated expression of inflammatory cytokines and chemokines on monocytes (CD14+) from blood samples collected prior to and after the completion of the ARI. Average CV measures were used to derive change scores that were used as dependent variables. Data were analyzed using multiple regression analyses with age, body mass index (BMI), and gender as covariates with changes in the expression of inflammatory cytokines as predictor variables. Emotional stress-induced increases in FVR were associated with stress-induced increases in TNF-a (partial r = .40, p < .0001), MCP-1 (partial r = .40, p < .0001), and IL-8 (partial r = .32, p = .0006). In contrast, decreases in FBF were associated with TNF-a (partial r = .20, p = .03), MCP-1 (partial r = .20, p = .03), and IL-8 (partial r = .21, p = .03). Increases in TNF-a were significantly associated with decreases in stress-induced systolic BP (partial r = .20, p = .03) and HR (partial r = .18, p = .05) responses consistent with the reported effect of TNF-a on cardiac contractility. Similarly, increases in MCP-1 (partial r = .23, p = .01) were associated with smaller SBP responses to the ARI. Combined, these data suggest that emotional stress evoked increases in the stimulated expression of proinflammatory cytokines and chemokines are related to stress-induced peripheral vasoconstriction and reduced cardiac responses. These observations suggest that inflammatory cytokines act as vasoactive mediators that regulate stress-induced vascular changes implicated in both coronary heart disease (CHD) and hypertension.

Emotional stress-induced increases in stimulated expression of cytokines and chemokines predict peripheral vasoconstriction in apparently healthy men and women

els, the molar ratio of ASD/cortisol, and ASD/17OHP increased in MRA-treated patients (p at least <.004). Serum levels of estrone and 17b-estradiol did not change. However, the molar ratio of estrone/ASD (an indicator of aromatization) decreased during 12 weeks of treatment (p = .001). In conclusion, neutralization of IL-6 increased secretion of biologically active adrenal androgens in relation to precursor hormones and estrogens. This is another important indication that proinflammatory cytokines perturb adrenal androgen steroidogenesis in patients with RA.