Effects of Ligustrazine on Bone Marrow Microvessel Systemin the Early Period of Acute Radiation Injury in Mice

Sublethally irradiated mice were immediately treated with 250 mg/kg Ligustrazine Phosphiatis intraperitoneally twice a day for seven days, and the bone marrow sections of ulna were observed. On the 5th day, the number of bone marrow microvessels of the Ligustrazine group was much greater than that of the control group. On the 7th day, the amount of the control group decreased to normal, while the ligustrazine group was still increasing, and the microvessel area was enlarged obviously. The percentage of the hematopoietic tissue volume in bone marrow between the two groups had no significant difference in the first 7days. On the 7th day after irradiation, the peripheral neutrophilic granulocytes increased in the Ligustrazine group- The results suggested that early use of Ligustrazine after acute radiation injury might improve the blood supply of bone marrow, and be helpful for recovery of hematopoiesis.

Effect of Ligustrazine on Expressions of Basic Fibroblast Growth Factor and Its Receptor in Bone Marrow of Mice with Acute Radiation Injury

Objective: To study the expressions of basic fibroblast growth factor (bFGF) and its receptor (bFGFR) in bone marrow of mice with acute radiation injury, and to evaluate the effect of Ligustrazine (Lt) on them. Methods: Fifty-six Kunming mice of clean grade were randomly divided into 3 groups, the normal group, the control group and the Lt group. Mice in the latter two groups were once homogeneously systemic irradiated with 6.0 Gy of 60 Co, with the absorption dose rate of 0. 56 Gy/min, then treated with saline (0.2 ml/ mice) or Lt (2 mg/mice) respectively, twice a day through gastrogavage for successive 13 days. Mice were sacrificed in batch on the 3rd, 7th and 14th day by cervical dislocation to collect the bilateral femoral bone marrow for preparing bone marrow mono-nuclear cell (BMMNC) suspension. The bFGFR expression on surface of BMMNC was determined by flow cytometry; and the bFGF expres-sion level in one side of femoral bone marrow tissue was detected by immunohistochemistry with SABC-AP assay. Results: The bFGF expression in bone marrow of mice on the 3rd, 7th and 14th day after acute radiation injury all were significantly lower than that of the normal mice (P<0.05 or P<0.01). The expressions of bFGF and bFGFR in the Lt group detected were significantly higher than that in the control group detected at the corresponding time points (P<0.05 or P < 0.01). Conclusion:By way of enhancing bFGF expression in bone marrow and bFGFR expression on surface of BMMNC to accelerate the repairing of hemopoietic micro-environment in bone marrow might be one of the mechanisms of Lt in promoting hemopoietic function reconstitution after acute radiation injury.Original article on CJITWM (Chin) 2004;24(5):439

Gastrointestinal radiation injury:Prevention and treatment

With the recent advances in detection and treatment of cancer,there is an increasing emphasis on the efficacy and safety aspects of cancer therapy.Radiation therapy is a common treatment for a wide variety of cancers,either alone or in combination with other treatments.Ionising radiation injury to the gastrointestinal tract is a frequent side effect of radiation therapy and a considerable proportion of patients suffer acute or chronic gastrointestinal symptoms as a result.These side effects often cause morbidity and may in some cases lower the efficacy of radiotherapy treatment.Radiation injury to the gastrointestinal tract can be minimised by either of two strategies:technical strategies which aim to physically shift radiation dose away from the normal intestinal tissues,and biological strategies which aim to modulate the normal tissue response to ionising radiation or to increase its resistance to it.Although considerable improvement in the safety of radiotherapy treatment has been achieved through the use of modern optimised planning and delivery techniques,biological techniques may offer additional further promise.Different agents have been used to prevent or minimize the severity of gastrointestinal injury induced by ionising radiation exposure,including biological,chemical and pharmacological agents.In this review we aim to discuss various technical strategies to prevent gastrointestinal injury during cancer radiotherapy,examine the different therapeutic options for acute and chronic gastrointestinal radiation injury and outline some examples of research directions and considerations for prevention at a pre-clinical level.

Radioprotective effects of the expression of FLT3 ligand regulated by Egr-1 regulated element on radiation injury of SCID mice

Objective: In order to explore the radioprotective effects of the expression of hematopoietic growth factors regulated by radio-inducible promoter on radiation injury. Methods:The human FL (Flt3 ligand) cDNA and EGFP (enhanced green fluorescent protein) cDNA were linked together with IRES and then inserted into the eukaryotic expression vector pCI-Egr, which was constructed by substituting CMV promoter in pCIneo with the Egr-1 promoter (Egr-EF). The vector was transferred into human bone marrow stromal ...

Practical approaches to effective management of intestinal radiation injury:Benefit of resectional surgery

AIM:To study the outcome of patients undergoing surgical resection of the bowel for sustained radiation-induced damage intractable to conservative management.METHODS:During a 7-year period we operated on 17 cases (5 male,12 female) admitted to our surgical department with intestinal radiation injury (IRI).They were originally treated for a pelvic malignancy by surgical resection followed by postoperative radiotherapy.During follow-up,they developed radiation enteritis requiring surgical treatment due to failure of conservative management.RESULTS:IRI was located in the terminal ileum in 12 patients,in the rectum in 2 patients,in the descending colon in 2 patients,and in the cecum in one patient.All patients had resection of the affected region(s).There were no postoperative deaths,while 3 cases presented with postoperative complications (17.7%).All patients remained free of symptoms without evidence of recurrence of IRI for a median follow-up period of 42 mo (range,6-96 mo).CONCLUSION:We report a favorable outcome without IRI recurrence of 17 patients treated by resection of the diseased bowel segment.

DTI and pathological changes in a rabbit model of radiation injury to the spinal cord after ^(125)I radioactive seed implantation

Excessive radiation exposure may lead to edema of the spinal cord and deterioration of the nervous system. Magnetic resonance imaging can be used to judge and assess the extent of edema and to evaluate pathological changes and thus may be used for the evaluation of spinal cord injuries caused by radiation therapy. Radioactive ^125I seeds to irradiate 90% of the spinal cord tissue at doses of 40–100 Gy （D90） were implanted in rabbits at T10 to induce radiation injury, and we evaluated their safety for use in the spinal cord. Diffusion tensor imaging showed that with increased D90, the apparent diffusion coefficient and fractional anisotropy values were increased. Moreover, pathological damage of neurons and microvessels in the gray matter and white matter was aggravated. At 2 months after implantation, obvious pathological injury was visible in the spinal cords of each group. Magnetic resonance diffusion tensor imaging revealed the radiation injury to the spinal cord, and we quantified the degree of spinal cord injury through apparent diffusion coefficient and fractional anisotropy.

Delayed Thoracic Radiation Injury

A case of delayed thoracic radiation injury occurring many years after an initial lung insult is presented. This case involves an individual who developed acute respiratory failure due to severe pleural fibrosis or fibrothorax possibly as a result of distant radiation therapy for Hodgkins disease.

Treatment of radiation-induced brain injury with bisdemethoxycurcumin

Radiation therapy is considered the most effective non-surgical treatment for brain tumors.However,there are no available treatments for radiation-induced brain injury.Bisdemethoxycurcumin(BDMC)is a demethoxy derivative of curcumin that has anti-proliferative,anti-inflammatory,and anti-oxidant properties.To determine whether BDMC has the potential to treat radiation-induced brain injury,in this study,we established a rat model of radiation-induced brain injury by administe ring a single 30-Gy vertical dose of irradiation to the whole brain,followed by intraperitoneal injection of 500μL of a 100 mg/kg BDMC solution every day for 5 successive weeks.Our res ults showed that BDMC increased the body weight of rats with radiation-induced brain injury,improved lea rning and memory,attenuated brain edema,inhibited astrocyte activation,and reduced oxidative stress.These findings suggest that BDMC protects against radiationinduced brain injury.

Lycium barbarum polysaccharide ameliorates radiation-induced brain injury by regulating gut microbiota

Objective: To determine the extent to which Lycium barbarum polysaccharide(LBP) improves60Co γ-ray radiation-induced brain injury(RIBI) by regulating the gut microbiota.Methods: The RIBI model of mice was established with the appropriate dose of60Co γ-ray to identify the changes in the body weight, behaviors, gut microbiota, and inflammatory reactions of mice. Mice were randomly divided into healthy, RIBI model, and LBP groups. The related inflammatory cytokines were determined using an enzyme linked immunosorbent assay kit. Then, 16S rRNA sequencings of feces were carried out to evaluate the differences in intestinal flora.Results: Compared with the spontaneous activity and exploratory spirit of the healthy group, those traits in the RIBI model mice in the open field significantly decreased, the freezing time in the elevated plus maze(EPM) significantly increased, and the number of times the mice discriminated the novel object was significantly lower. Hematoxylin-eosin slides showed that the main histopathological changes of RIBI occurred in the hippocampus. In addition, the diversity and relative abundances ratio of the gut bacterial phylum, order, family, and genus in the model group varied widely. Changes in Bacteroidetes,Firmicutes, and Proteobacteria were the most obvious after head radiation exposure. In comparison, LBP could accelerate the recovery of weight loss in RIBI mice. The frequency that mice entered the center of the open field, facing the open arm in the EPM, and the number of times they discriminated the novel object were significantly increased with LBP administration. LBP could also reduce the levels of inflammatory factor caused by RIBI. LBP increased the diversity and abundance of gut microbiota in RIBI model mice. In addition, LBP increased the relative abundance of Bacteroidetes but decreased the levels of Firmicutes and Proteobacteria for irradiated mice.Conclusion: LBP can improve depression and tension by regulating the composition of gut microbiota,including lowering the relative abundance of Clostridia and Burkholderiales and raising that of Lactobacillales. Thus, LBP provides a new strategy for improving the protective effects of RIBI.

Biomarkers Associated with Radiation-Induced Lung Injury in Cancer Patients

Radiotherapy (RT) is a common and effective non-surgical treatment for thoracic solid tumors, and radiation-induced lung injury (RILI) is the most common side effect of radiotherapy. Even if RT is effective in the treatment of cancer patients, severe radiation pneumonitis (RP) or pulmonary fibrosis (PF) can reduce the quality of life of patients and may even lead to serious consequences of death. Therefore, how to overcome the problem of accurate prediction and early diagnosis of RT for pulmonary toxicity is very important. This review summarizes the related factors of RILI and the related biomarkers for early prediction of RILI.

Effects of Zaizhang－I，A Traditional Chinese Herbal Medicine，on Hematopoietic Recovery from Radiation Injury In Mice

Effects of Zaizhang-I (ZZ-I)on the recovery of hemopoietic systems from radiation injury were investigated. Mice,irradiated with 6.0 Gy -rays,were injected i. p. once daily for 7 consecutive days with either ZZ-I or saline(0.01 ml/g body wt.). The experiments showed that ZZ-I significantly promoted the recovery of not only peripheral WBC, BMC, CFU-S and CFU-GM but also the abnormal femur micro-vessel system such as blood vessels and sinus ectasia, hyperemia and hemorrhage etc.These results suggest that ZZ-I could accelerate hemopoietic recovery from radiation injury in mice by stimulating hemopoietic stem cells and improving hemopoietic inductive microenvironment (HIM).

Clinical and Experimental Study on Prevention and Treatment of Acute Radiation Injury in Nasopharyngeal Carcinoma Patients by Yiqi Huoxue Yangyin Recipe (益气活血养阴方)

Objective: To observe the effect of Chinese herbal medicine in alleviating acute toxic adverse effect of radiotherapy and on growth of stromal cells in bone marrow. Methods: Seventy two patients with nasopharyngeal carcinoma (NPC) were randomly divided into two groups. Radical radiotherapy was applied to both groups. In the radiotherapeutic period, to the 36 patients in the treated group, Yiqi Huoxue Yangyin Recipe (YHYR) was given additionally by oral taking and compressing on radiation area, and to the 36 patients in the control group, vitamin B 12 solution was given for gargling or compressing. Experimental study was carried out in rats of two groups, irradiated with 5.0 Gy X ray and treated with YHYR or normal saline intraperitoneally, to observe the colony forming unit fibroblastoid (CFU F) in cultured bone marrow stromal cells (BMSC), taken from the rats at different time.Results: The oral mucomembranous radiation damage occurred in 47.2% of the treated group when the dose of radiation reached to 41.4±9.4 Gy, while in the control group, it was 91.7% when the dose reached to 30.9±8.9 Gy. The skin radiation damage occurrence rate in the two groups was 13.9% and 33.3% respectively when the dose of radiation reached to 50.2±5.6 Gy and 43.2±6.3 Gy respectively. Comparison of the two groups showed significant difference ( P <0.01), the radiation damage was significantly slighter in the treated group. Experimental study showed that the rats in the two groups were significantly different in occurrence and degree of bone marrow function inhibition, P <0.01. The numbers of CFU F in cultured BMSC of radiation damaged rats taken at respective different culture time were also significantly different between the two groups, P < 0.01 .Conclusion: YHYR could significantly reduce acute radiation damage of mucomembrane and skin, alleviate the inhibition on bone marrow function, and eliminate the injury of radiation on BMSC.

The role of crm-1 in ionizing radiation-induced nervous system dysfunction in Caenorhabditis elegans

Ionizing radiation can cause changes in nervous system function.However,the underlying mechanism remains unclear.In this study,Coenorhabditis elegans(C.elegans)was irradiated with 75 Gy of ^(60)Co whole-body γ radiation.Behavioral indicators(head thrashes,touch avoidance,and foraging),and the development of dopaminergic neurons related to behavioral function,were evaluated to assess the effects of ionizing radiation on nervous system function in C.elegans.Various behaviors were impaired after whole-body irradiation and degeneration of dopamine neurons was observed.This suggests that 75 Gy of γ radiation is sufficient to induce nervous system dysfunction.The genes nhr-76 and crm-1,which are reported to be related to nervous system function in human and mouse,were screened by transcriptome sequencing and bioinformatics analysis after irradiation or sham irradiation.The expression levels of these two genes were increased after radiation.Next,RNAi technology was used to inhibit the expression of crm-1,a gene whose homologs are associated with motor neuron development in other species.Downregulation of crm-1 expression effectively alleviated the deleterious effects of ionizing radiation on head thrashes and touch avoidance.It was also found that the expression level of crm-1 was regulated by the nuclear receptor gene nhr-76.The results of this study suggest that knocking down the expression level of nhr-76 can reduce the expression level of crm-1,while down-regulating the expression level of crm-1 can alleviate behavioral disorders induced by ionizing radiation.Therefore,inhibition of crm-1 may be of interest as a potential therapeutic target for ionizing radiation-induced neurological dysfunction.

Development of radiation countermeasure agents for acute radiation syndromes

The risk of internal and external exposure to ionizing radiation(IR)has increased alongside the development and implementation of nuclear technology.Therefore,serious security issues have emerged globally,and there has been an increase in the number of studies focusing on radiological prevention and medical countermeasures.Radioprotective drugs are particularly important components of emergency medical preparedness strategies for the clinical management of IR-induced injuries.However,a few drugs have been approved to date to treat such injuries,and the related mechanisms are not entirely understood.Thus,the aim of the present review was to provide a brief overview of the World Health Organization's updated list of essential medicines for 2023 for the proper management of national stockpiles and the treatment of radiological emergencies.This review also discusses the types of radiation-induced health injuries and the related mechanisms,as well as the development of various radioprotective agents,including Chinese herbal medicines,for which significant survival benefits have been demonstrated in animal models of acute radiation syndrome.

Establishment of injury models in studies of biological effects induced by microwave radiation

Microwave radiation has been widely used in various fields,such as communication,industry,medical treatment,and military applications.Microwave radiation may cause injuries to both the structures and functions of various organs,such as the brain,heart,reproductive organs,and endocrine organs,which endanger human health.Therefore,it is both theoretically and clinically important to conduct studies on the biological effects induced by microwave radiation.The successful establishment of injury models is of great importance to the reliability and reproducibility of these studies.In this article,we review the microwave exposure conditions,subjects used to establish injury models,the methods used for the assessment of the injuries,and the indicators implemented to evaluate the success of injury model establishment in studies on biological effects induced by microwave radiation.

Therapeutic implications of exosomes in the treatment of radiation injury

Radiotherapy is one of the main cancer treatments,but it may damage normal tissue and cause various side effects.At present,radioprotective agents used in clinics have side effects such as nausea,vomiting,diarrhea and hypotension,which limit their clinical application.It has been found that exosomes play an indispensable role in radiation injury.Exosomes are lipid bilayer vesicles that carry various bioactive substances,such as proteins,lipids and microRNA(miRNA),that play a key role in cell-to-cell communication and affect tissue injury and repair.In addition,studies have shown that radiation can increase the uptake of exosomes in cells and affect the composition and secretion of exosomes.Here,we review the existing studies and discuss the effects of radiation on exosomes and the role of exosomes in radiation injury,aiming to provide new insights for the treatment of radiation injury.

Radiation dermatitis wet healing:a concept analysis

Objective:To explore the concept of radiation dermatitis wet healing through a literature review and provide references for future treatment of patients with radiation skin injury.Methods:Related ar ticles selected from China National Knowledge Infrastructure(CNKI),Wanfang Database,Pub Med,Web of Science,Medline,and EBSCO were analyzed with Rodger’s concept analysis.Results:We identified the application status of wet healing in domestic and foreign literature,defined explicit attributes of the procedure,and clarified concepts related to wet healing of radiation skin injury to provide a reference for the management of radiation dermatitis with wet healing.Conclusions:Treatment of radiation dermatitis with wet healing is a unique procedure.Analyzing this concept can contribute to its development in the future and can offer a theoretical basis for treatment of patients with radiation skin injury.

Expression of Angiotensin Ⅱ and Aldosterone in Radiation-induced Lung Injury

Objective Radiation-induced lung injury （RILl） is the most common, dose-limiting complication in thoracic malignancy radiotherapy. Considering its negative impact on patients and restrictions to efficacy, the mechanism of RILl was studied. Methods Wistar rats were locally irradiated with a single dose of 0, 16, and 20 Gy to the right half of the lung to establish a lung injury model. Two and six months after irradiation, the right half of the rat lung tissue was removed, and the concentrations of TGF-[31, angiotensin II, and aldosterone were determined via enzyme-linked immunosorbent assay. Results Statistical differences were observed in the expression levels of angiotensin II and aldosterone between the non-irradiation and irradiation groups. Moreover, the expression level of the angiotensin II-aldosterone system increased with increasing doses, and the difference was still observed as time progressed. Conclusions Angiotensin II-aldosterone system has an important pathophysiological function in the progression of RILI.

Differential Proteomics Reveals the Potential Injury Mechanism Induced by Heavy Ion Radiation in Mice Ovaries

In the present study, we used a proteomics approach based on a two-dimensional electrophoresis （2-DE） reference map to investigate protein expression in the ovarian tissues of pubertal Swiss-Webster mice subjected to carbon ion radiation （CIR）. Among the identified proteins, ubiquitin carboxy-terminal hydrolase L1 （UCH-L1） is associated with the cell cycle[1] and that it influences proliferation in ovarian tissues. We analyzed the expression of UCH-L1 and the proliferation marker proliferation cell nuclear antigen （PCNA） following CIR using immunoblotting and immunofluorescence. The proteomics and biochemical results provide insight into the underlying mechanisms of CIR toxicity in ovarian tissues.

Rabbit model of radiation-induced lung injury

Objective:To explore the feasibility of establishing an animal model of chronic radiationinduced lung injury.Methods:Twenty-eight New Zealand white rabbits were randomly divided into 3 groups(the right lung irradiation group,the whole lung irradiation group and the control group).Animal model of radiation-induced lung injury was established b) highdoes radiotherapy in the irradiation groups,then all rabbits underwent CT and pathological examinations at 1.2.4.8.12.16 weeks,respectively after radiation.Results:Within 4 weeks of irradiation,some rabbits in the right lung irradiation group and whole lung irradiation group died. CT and pathological examinations all showed acute radiation pneumonitis.At 8-12 weeks after irradiation,CT scanning showed ground glass samples signs,patchy shadows and fibrotic stripes. Pathological examination showed the fibrosis pulmonary alveolar wall thickened obviously. Conclusions:The clinical animal model of chronic radiation-induced lung injury which corresponds to practical conditions in clinic can be successfully established.