Novel stress increases hypothalamic-pituitary-adrenal activity in mice with a raised bite

Background and objectiveIn humans, occlusal disharmony may cause various physical complaints, including head and neck ache, stiffness in the shoulder and neck, and arthrosis of the temporomandibular joints. Occlusal disharmony induced by raising the bite in rodents, increases plasma corticosterone levels, which leads to morphologic changes in the hippocampus and altered hippocampus-related behavior. The paraventricular nucleus (PVN) of the hypothalamus regulates the hypothalamic-pituitary-adrenal system. Chronically stressed animals exposed to a novel stress exhibit higher adrenocorticotropic hormone levels than naive control animals. We hypothesized that there would be different response of the corticotrophin releasing hormone (CRH) and arginine vasopressin (AVP) to a novel acute stress with occlusal disharmony.DesignIn order to investigate how exposure of mice with occlusal disharmony to a novel acute stress (restraint stress) affects the PVN, we induced occlusal disharmony by raising the vertical dimension of the bite (bite-raised condition) and examined the expression of corticotrophin releasing hormone (CRH) mRNA and arginine vasopressin (AVP) mRNA in mouse PVN.ResultsCRH mRNA expression was increased in the PVN of the bite-raised group 90 min after the bite-raising procedure, but the expression was recovered to the control level at 14 days. AVP mRNA expression in the PVN was normal at 90 min, and increased significantly 14 days after the bite-raising procedure. Exposure to restraint stress in the bite-raised mice induced a significant increase in CRH mRNA expression in the PVN.ConclusionsThe bite-raising procedure induced a rapid CRH mRNA response and a slower AVP mRNA response in the parvocellular PVN of the hypothalamus. Exposure to a novel stress following the bite-raising procedure further reinforced the CRH stress response. Thus, occlusal disharmony, such as that induced by raising the bite, may be a risk factor for hypersensitivity to a novel stress.     

The Seventh Door

An oncologist reflects on the personal toll physicians experience while taking care of the very sick and the journey they must take, facing real and perceived failures when patients suffer poor outcomes, to find the renewed energy to go on with their chosen mission.     

Xuezhikang ameliorates contrast media-induced nephropathy in rats via suppression of oxidative stress,inflammatory responses and apoptosis

Background: The aim of this study was to assess the preventive effect of xuezhikang (XZK) to replace atorvastatin on the contrast media-induced acute kidney injury (CI-AKI).

Methods: The male Sprague–Dawley rats were divided into five groups: group 1 (sham), injected with normal saline; group 2 (XZK), treated with XZK; group 3 contrast media (CM), injected with CM; group 4 (CM?+?ATO), injected with CM?+?pretreatment with atorvastatin; group 5 (CM?+?XZK), injected with CM?+?pretreatment with XZK. Twenty-four hours after injection with normal saline or CM, the blood sample and the kidneys were collected for the measurement of biochemical parameters, oxidative stress markers, nitric oxide production, inflammatory parameters, as well as renal histopathology and apoptosis detection.

Results: Our results indicated that XZK restored the renal function by reducing serum blood urea nitrogen (BUN) and serum creatinine (Scr), depressing renal malondialdehyde (MDA), increasing renal NO production, decreasing TNF-ɑ and IL-6 expression, attenuating renal pathological changes and inhibiting the apoptosis of renal tubular cells.

Conclusion: XZK’s therapeutic effect is similar, or even better than atorvastatin at the same effectual dose in some parts.     

p66~(Shc)基因敲除对小鼠缺血缺氧性脑损伤的保护作用

目的探讨p66Shc基因敲除对小鼠缺血缺氧性脑损伤(hypoxic-ischemic brain injury,HIBI)的保护作用及可能的机理。方法将C57小鼠分为假手术组(野生型,sham operation,SO)、HIBI野生型组(hypoxic-ischemic wild type,HIWT)和HIBI-p66Shc基因敲除组(hypoxic-ischemic knock-out,HIKO),每组20只。采用右侧颈总动脉结扎-浸入低氧环境的方法制备小鼠HIBI模型。随后对各组小鼠神经功能障碍情况、HIBI损伤灶体积、血清神经元特异性烯醇化酶(neuronspecific enolase,NSE)水平和脑组织匀浆中白细胞介素-1β(interleukin-1β,IL-1β)的水平进行测量和比对。结果 HIBI造模24 h后,HIKO组小鼠的神经功能缺损程度评分(1.87±0.30)低于HIWT组小鼠(2.49±0.26),HIKO组小鼠脑梗死灶体积[(22.66±4.20)mm3]小于HIWT组小鼠[(27.31±3.23)mm3],HIKO组小鼠血清NSE含量[(8.97±0.74)ng/ml]显著低于HIWT组小鼠[(11.26±0.68)ng/ml],HIKO组小鼠脑组织IL-1β含量[(1.72±0.30)ng/ml]显著低于HIWT组小鼠[(2.07±0.28)ng/ml],P均<0.05。结论 p66Shc基因敲除可通过降低小鼠HIBI发生后脑组织IL-1β的表达,起到脑保护作用。     

Lung cancer: What are the links with oxidative stress,physical activity and nutrition

Oxidative stress appears to play an essential role as a secondary messenger in the normal regulation of a variety of physiological processes, such as apoptosis, survival, and proliferative signaling pathways. Oxidative stress also plays important roles in the pathogenesis of many diseases, including aging, degenerative disease, and cancer. Among cancers, lung cancer is the leading cause of cancer in the Western world. Lung cancer is the commonest fatal cancer whose risk is dependent on the number of cigarettes smoked per day as well as the number of years smoking, some components of cigarette smoke inducing oxidative stress by transmitting or generating oxidative stress. It can be subdivided into two broad categories, small cell lung cancer and non-small-cell lung cancer, the latter is the most common type. Distinct measures of primary and secondary prevention have been investigated to reduce the risk of morbidity and mortality caused by lung cancer. Among them, it seems that physical activity and nutrition have some beneficial effects. However, physical activity can have different influences on carcinogenesis, depending on energy supply, strength and frequency of exercise loads as well as the degree of exercise-mediated oxidative stress. Micronutrient supplementation seems to have a positive impact in lung surgery, particularly as an antioxidant, even if the role of micronutrients in lung cancer remains controversial. The purpose of this review is to examine lung cancer in relation to oxidative stress, physical activity, and nutrition.     

Relationship between plasma osteopontin and oxidative stress in patients with coronary artery disease

Background: It is known that oxidative stress plays an important role in the pathogenesis of atherosclerosis and that an association exists between osteopontin (OPN) and atherosclerosis. Objectives: It was proposed that malondialdehyde (MDA), a biomarker of lipid peroxidation and oxidative stress, would be related to plasma OPN levels in patients with coronary artery disease (CAD). Methods/results: Plasma OPN and MDA levels were measured in 71 patients (60 males and 11 females; mean age 61.7 ± 10 years). Fifty-eight patients had significant CAD (group I) and 13 patients were free of CAD as defined angiographically (group II). Plasma OPN was measured by enzyme-linked immunosorbent assay (ELISA), while MDA was determined spectrophotometrically. Multivariate regression analysis revealed that ln-transformed OPN levels were independently associated with MDA after adjustment for age, hypertension and diabetes mellitus (R² = 0.278, p = 0.0004 and β regression coefficient = 0.252 [standard error = 0.0958], p = 0.011). OPN and MDA levels were higher in patients with diabetes (73.6 ± 36.2 ng/ml versus 56.1 ± 30.9 ng/ml, p = 0.02 and 2.5 ± 0.5 μM versus 2.0 ± 0.5 μM, p = 0.002, respectively). Conclusions: The association between OPN and MDA levels in patients with CAD suggests an interaction between OPN and oxidative stress. This interaction may play a role in the pathogenesis of atherosclerosis.     

Combined Effects of Multiple Endoplasmic Reticulum Stresses on Cytokine Secretion in Macrophage

Cells show various stress signs when they are challenged with severe physiological problems. Majority of such cellular stresses are conveyed to endoplasmic reticulum (ER) and unfolded protein response (UPR) serves as typical defense mechanism against ER stress. This study investigated an interaction between ER stress agents using macropage cell line Raw 264.7. When activated by lipopolysaccharide (LPS), the cell lines showed typical indicators of ER stress. Along with molecular chaperones, the activation process leads to the production of additional infl ammatory mediators. Following activation, the macrophage cell line was further treated with TUN and characterized in terms of chaperone expression and cytokine secretion. When treated with TUN, the activated macrophage cell leads to increased secretion of IL-6 although expression of ER stress markers, GRP94 and GRP78 increased. The secretion of cytokines continued until the addition of BFA which inhibits protein targeting from ER to Golgi. However, secretion of cytokines was ceased upon dual treatments with BFA and TG. This result strongly implies that cells may differently deal with various polypeptides depending on the urgency in cellular function under ER stress. Considering IL-6 is one of the most important signal molecules in macrophage, the molecule might be able to circumvent ER stress and UPR to reach its targeting site.     

Proficiency in English sentence stress production by Cantonese speakers who speak English as a second language (ESL)

The present study examined English sentence stress produced by native Cantonese speakers who were speaking English as a second language (ESL). Cantonese ESL speakers' proficiency in English stress production as perceived by English-speaking listeners was also studied. Acoustical parameters associated with sentence stress including fundamental frequency (F0), vowel duration, and intensity were measured from the English sentences produced by 40 Cantonese ESL speakers. Data were compared with those obtained from 40 native speakers of American English. The speech samples were also judged by eight naïve listeners who were native speakers of American English for placement, degree, and naturalness of stress. Results showed that Cantonese ESL speakers were able to use F0, vowel duration, and intensity to differentiate sentence stress patterns. Yet, both female and male Cantonese ESL speakers exhibited consistently higher F0 in stressed words than English speakers. Overall, Cantonese ESL speakers were found to be proficient in using duration and intensity to signal sentence stress, in a way comparable with English speakers. In addition, F0 and intensity were found to correlate closely with perceptual judgement and the degree of stress with the naturalness of stress.     

Prognostiske prediktorer og langtidsforløpet for nevroser og andre psykiske lidelser: 20 års follow-up fra en psykiatrisk spesialistpraksis

Den psykiatriske solopraksis gir muligheter for utvikling av et nÆrt lege-pasientforhold. Vestfold er Norges minste fylke med en befolkning på ca. 174 000 i 1960 stigende til ca. 187 000 i 1980. Forfatteren har arbeidet som psykiatrisk spesialist i Vestfold i hele dette tidsrommet og har således hatt muligheter for å følge mange av pasientene gjennom et langt avsnitt av deres liv. Han har på den måten fått et inntrykk av langtidsforløpet ved psykiske lidelser og likeledes en formening om hvilke kategorier pasienter sorn klarer seg godt eller dårlig. Hensikten med denne undersøkelsen er å objektivisere forløpet og dokumentere bakgrunnsfaktorer med relasjon til prognosen. Ifølge Strømgren (1980) er dette to av flere mulige målsettinger for longitudinelle studier, som ellers stort sett har hatt sitt utgangspunkt i hospitaliserte pasienter og som oftest i endogene psykoser. Foreliggende arbeid omhandler imidlertid et diagnostisert uselektert poliklinisk klientell, og diagnostisk består materialet hovedsaklig av nevroser, men med innslag av psykoser, krisereaksjoner, karakteravvik og misbruksproblematikk.

Forfatteren er takknemlig for finansiell støtte fra Anders Jahres fond til vitenskapens fremme og for verdifull veiledning ved dosent dr. med. Ole Bratfos.     

Prenatal stress increased Snk Polo-like kinase 2, SCF β-TrCP ubiquitin ligase and ubiquitination of SPAR in the hippocampus of the offspring at adulthood

Exposure to excessive glucocorticoids during fetal development period contributes to later life psychopathology. Prenatal stress decreases dendritic spine density and impair LTP in the hippocampus of rat pups, however, the mechanisms regulating these changes are still unclear.