Radiation treatment of acute inflammation in mice

Purpose: Low-dose radiotherapy (RT) has often been used effectively for the treatment of a variety of benign diseases, particularly those with acute inflammatory features. Here we report findings on radiation treatment of acute inflammation using a murine carrageenin air pouch model.

Materials and methods: Air pouches raised on the dorsal surface of mice were injected with λ carrageenin and were irradiated 6 h later with doses ranging from 0 – 5 Gy. Treatment success was evaluated at various times thereafter by volume of exudate and number of inflammatory cells, and levels of inflammation-related cytokines tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and transforming growth factor beta-1 (TGFβ-1), and expression of inducible nitric oxide synthase (iNOS), heme oxygenase-1 (HO-1), cyclooxygenase-2 (COX-2) and inducible heat shock protein 70 (HSP70) as determined by enzyme-linked immunosorbent assay (ELISA) and Western blotting, respectively.

Results: Crude inflammatory parameters such as the amount of exudates and number of inflammatory cells remained largely unaffected by radiation or were even a slightly and transiently increased. However, the expression of iNOS was attenuated by radiation concomitant with an increase in the levels of HO-1 and HSP70. Cytokine levels varied with the radiation dose and the time point.

Conclusions: Ionizing radiation, even at low doses, functionally modulates inflammatory cells. Our findings indicate possible mechanisms as to how low-dose radiation may exert anti-inflammatory effects and provide the first evidence that heat shock proteins may be involved in this response.     

Cytochrome-c mediated a bystander response dependent on inducible nitric oxide synthase in irradiated hepatoma cells

Background:

Radiation-induced bystander effect (RIBE) has important implication in tumour radiotherapy, but the bystander signals are still not well known.

Methods:

The role of cytochrome-c (cyt-c) and free radicals in RIBE on human hepatoma cells HepG2 was investigated by detecting the formation of bystander micronuclei (MN) and the generation of endogenous cyt-c, inducible nitric oxide (NO) synthase (iNOS), NO, and reactive oxygen species (ROS) molecules.

Results:

When HepG2 cells were cocultured with an equal number of irradiated HepG2 cells, the yield of MN in the nonirradiated bystander cells was increased in a manner depended on radiation dose and cell coculture time, but it was diminished when the cells were treated with cyclosporin A (CsA), an inhibitor of cyt-c release. Meanwhile the CsA treatment inhibited radiation-induced NO but not ROS. Both of the depressed bystander effect and NO generation in the CsA-treated cells were reversed when 5 μ cyt-c was added in the cell coculture medium. But these exogenous cyt-c-mediated overproductions of NO and bystander MN were abolished when the cells were pretreated with s-methylisothiourea sulphate, an iNOS inhibitor.

Conclusion:

Radiation-induced cyt-c has a profound role in regulating bystander response through an iNOS-triggered NO signal but not ROS in HepG2 cells.     

Pomegranate peel and fruit extracts: A review of potential anti-inflammatory and anti-infective effects

Ethnopharmacological relevance

Punica granatum L. (Punicaceae) has been used for centuries in many cultures for the prevention and treatment of a wide number of health disorders such as inflammation, diabetes, diarrhea, dysentery, dental plaque and to combat intestinal infections and malarial parasites.

Aim of the review

This review aims at providing an up-to-date overview of the chemical constituents, traditional uses, phytochemistry, pharmacology and toxicology of Punica granatum L. Moreover, the focus of this review is the possible exploitation of this species to treat different diseases and to suggest future investigations.

Materials and methods

An extensive and systematic review of the extant literature was carried out, and the data under various sections were identified by using a computerized bibliographic search via PubMed, Web of Science and Google Scholar. All abstracts and full-text articles were examined. The most relevant articles were selected for screening and inclusion in this review.

Key findings

A variety of pomegranate ethnomedical uses have been recorded. Additionally, over the last decade, there has been a dramatic increase of interest in pomegranate as a medicinal and nutritional product due to its n1ewly identified potential health effects, which include treatment and prevention of cancer and cardiovascular diseases. From the toxicological perspective, pomegranate fruit juice, extracts and preparations have been proven to be safe.

Conclusions

The ethnopharmacological relevance of pomegranate is fully justified by the most recent findings indicating the fruit is a medicinal and nutritional agent useful for treating a wide range of human disorders and maladies. Further investigations are needed to fully understand the mode of action of the active constituents and to fully exploit pomegranate’s preventive and therapeutic potential.     

Rhynchophylline Attenuates LPS‐induced Pro‐inflammatory Responses through Down‐regulation of MAPK/NF‐κB Signaling Pathways in Primary Microglia

Excessive activation of microglial cells has been implicated in various types of neuroinflammation. Suppression of microglial activation would have therapeutic benefits, leading to the alleviation of the progression of neurodegeneration. In this study, the inhibitory effects of rhynchophylline (RIN), a tetracyclic oxindole alkaloid component isolated from Uncaria rhynchophylla (Miq.) Jacks., on the production of pro‐inflammatory mediators were investigated in lipopolysaccharide (LPS)‐stimulated microglia. The results showed that RIN markedly reduced the production of nitric oxide (NO), prostaglandins E₂ (PGE₂), monocyte chemoattractant protein (MCP‐1), tumor necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β) in LPS‐activated microglia. The mRNA expression levels of iNOS and COX‐2 were also depressed by RIN in a concentration‐dependent manner. Further studies revealed that RIN blocked IκBα phosphorylation and degradation, inhibited the phosphorylation of mitogen‐activated protein kinases (MAPKs). In summary, these data suggest that RIN suppresses inflammatory responses of microglia and may act as a potential therapeutic agent for various neurodegenerative diseases involving neuroinflammation. Copyright © 2012 John Wiley & Sons, Ltd.     

颈交感神经干离断对局灶性脑缺血再灌注后大鼠海马iNOS表达的影响

目的采用颈交感干离断（TCST）模拟星状神经节阻滞，观察其对局灶性脑缺血再灌注损伤（CIRI）大鼠脑梗死容积及海马诱导型一氧化氮合酶（iNOS）表达等的影响，并探讨其脑保护作用的机制。方法将大鼠随机分成实验组（A组）、对照组（B组）和假手术组（C组）；采用线栓法行大脑中动脉栓塞（MCAO）制作大鼠局灶性CIRI模型，A组于TCST后即行MCAO，2h后再恢复灌注；B组为单纯CIRI组；C组仅完成与A组相似的手术步骤但不造成MCAO、不行TCST；再灌注24h后观察各组大鼠神经行为学评分、脑梗死容积及海马iNOs的表达变化。结果A组大鼠脑梗死容积和神经行为学评分均低于B组（P〈0．05）；与A组、C组相比，B组大鼠海马iNOS的表达增加（P〈0．05），而A组与C组间无显著差异（P〉0．05）。结论TCST可通过下调大鼠海马iNOS的表达而对局灶性CIRI发挥脑保护作用。     

丹参酮ⅡA对脑缺血再灌注损伤大鼠脑组织及血清中NO含量及NOS、iNOS活性的影响

目的观察丹参酮Ⅱh（Tan ⅡA）对脑缺血再灌注损伤大鼠脑组织及血清中一氧化氮（NO）含量、一氧化氮合酶（NOS）及诱导型一氧化氮合酶（iNOS）活性的影响，探讨其对脑缺血再灌注损伤保护作用的可能机制。方法将大鼠随机分为假手术组、缺血再灌注组、Tan ⅡA低、高剂量组，线栓法建立局灶性脑缺血再灌注模型。Tan ⅡA高、低剂量组于术前连续灌胃给予高、低剂量Tan ⅡA 3d，每日1次。各组于脑缺血90min再灌注24h后进行HE染色，观察病理形态学变化，检测脑组织和血清中NO含量和NOS、iNOS活性的变化。结果Tan ⅡA高、低剂量组脑组织缺血损伤病理学改变明显轻于缺血再灌注组，Tan ⅡA高剂量组缺血改变亦轻于低剂量组。与假手术组比较，缺血再灌注组脑组织和血清中NO含量和NOS、iNOS活性明显升高；与缺血再灌注组比较，Tan ⅡA高、低剂量组脑组织和血清中N0含量和NOS、iNOS活性均明显降低，高、低剂量组之间差异具有统计学意义（P〈0．05）。结论Tan ⅡA可减轻神经元损伤程度，对缺血再灌注脑损伤具有保护作用，其机制可能与降低NOS、iNOS活性，减少NO含量有关。     

严重创伤早期大鼠下丘脑HSP70与iNOS表达与分布的时效关系

目的研究严重创伤早期大鼠下丘脑热休克蛋白(HSP)70与诱导型一氧化氮合酶(iNOS)转录表达变化分布和意义.方法采用BIM-Ⅲ型生物撞击机致大鼠胸部严重撞击伤,并造成单侧股骨骨折,运用S-ABC免疫组化、原位杂交技术测定下丘脑HSP70与iNOS及其mRNA的转录表达水平.结果正常对照组HSP70低水平表达,在伤后1小时即开始明显增高(P＜0.05),6小时达到峰值为正常的18倍,12小时后开始下降,24小时时主要集中在室旁核内;iNOS无基础表达,在伤后1小时开始出现,随HSP70同步增高,8小时达到高峰,较1小时时增加13倍.两者相关系数r=0.97601.结论严重创伤后早期下丘脑内HSP70和iNOS过度表达, 在严重创伤应激时下丘脑的损伤与抗损伤机制中起重要作用.     

Effect of a Korean Traditional Formulation, Hwaotang, on Superoxide Generation in Human Neutrophils, Platelet Aggregation in Human Blood, and Nitric Oxide, Prostaglandin E2 Production and Paw Oedema Induced by Carrageenan in Mice

Hwaotang, a traditional Korean medicinal formulation, is a dried decoctum of a mixture of 7 herbal medicines, consisting of Angelica gigantis Radix, Rehmanniae radix, Paeoniae radix, Ciniamomi cortex, Cnidii rhizoma, Persicae semen and Carthami flos. We have investigated that Hwaotang water extract (HOT) has various effects on stimulus-induced superoxide generation in human neutrophils. The effects of HOT on superoxide generation in human neutrophils were investigated. HOT significantly inhibited N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration-dependent manner, but not that induced by arachidonic acid (AA). On the other hand, HOT enhanced superoxide generation induced by phorbol 12-myristate 13-acetate (PMA) in a concentration-dependent manner. The superoxide generation induced by PMA with HOT was suppressed by staurosporine, an inhibitor of protein kinase C, but was not suppressed by genistein, an inhibitor of protein tyrosine kinase. Tyrosyl phosphorylation of a 58 kDa protein, which was increased by fMLP, was inhibited by HOT. HOT also inhibited the generation of a 47 kDa protein and platelet aggregation in human blood. The results suggest that protein tyrosine kinase participates in fMLP-mediated superoxide generation by HOT-treated human neutrophils. HOT inhibited neutrophil functions, including degranulation, superoxide generation, and leukotriene B4 production, without any effect on 5-lipoxygenase activity. HOT reduced nitric oxide (NO) and prostaglandin E2 production in mouse peritoneal macrophages stimulated with lipopolysaccharide, whereas no influence on the activity of iNOS, COX-2 or COX-1 was observed. HOT significantly reduced mouse paw oedema induced by carrageenan. Western blot analysis showed that HOT reduced the expression of iNOS and COX-2. The results indicate that HOT exerts anti-inflammatory effects related to the inhibition of neutrophil functions and of NO and prostaglandin E2 production, which could be due to a decreased expression of iNOS and COX-2.