research article dexmedetomidine reduced cytokine...

Hindawi Publishing CorporationMediators of InflammationVolume 2013 Article ID 627831 7 pageshttpdxdoiorg1011552013627831

Research ArticleDexmedetomidine Reduced Cytokine Release duringPostpartum Bleeding-Induced Multiple Organ DysfunctionSyndrome in Rats

Liu Xianbao1 Zhan Hong1 Zeng Xu2 Zhang Chunfang3 and Chen Dunjin3

1 Department of Anesthesiology Third Affiliated Hospital Guangzhou Medical University Guangzhou 510150 China2Department of Pathology Detroit Medical Center Harper University Hospital School of Medicine Wayne State University3990 John R Detroit MI 48201 USA

3Department of Gynecology and Obstetrics Third Affiliated Hospital Guangzhou Medical University Guangzhou 510150 China

Correspondence should be addressed to Zhan Hong 457163589qqcom

Received 25 June 2012 Revised 7 March 2013 Accepted 22 May 2013

Academic Editor Celeste C Finnerty

Copyright copy 2013 Liu Xianbao et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Dexmedetomidine (DEX) is an 1205722-adrenergic agonist It decreases the levels of norepinephrine release resulting in a reductionof postsynaptic adrenergic activity In the present study the effects of DEX on postpartum bleeding-induced multiple organdysfunction syndrome (BMODS) were studied in rats in which BMODS was induced by the combination of hypotension andclamping of the superiormesenteric arteryWe evaluated the role of dexmedetomidine (DEX) in cytokine release during postpartumBMODS in rats In summary the present study demonstrated that DEX administration reduced IFN-r and IL-4 release anddecreased lung injury during postpartum BMODS It is possible that DEX administration decreased inflammatory cytokineproduction in BMODS by inhibiting inflammation and free radical release by leukocytes independent of the DEX dose

1 Introduction

The most common cause of multiple organ dysfunction syn-drome (MODS) in obstetric patients is postpartum bleed-ing followed by gestational hypertension syndrome [1 2]Bleeding-induced multiple organ dysfunction syndrome(BMODS) is a rapidly progressive disease that commonlyoccurs in critically ill obstetric patients with a high mortalityrate It is also one of the major causes of death in the mater-nity intensive care unit (ICU) [2] BMODS induces diffuseischemia and functional impairment in multiple organ sys-tems and in severe cases can progress to diffuse intravascularcoagulation (DIC) [3] For this reason patients with a historyof heavy blood loss during delivery should be monitored inthe ICUThemanagement of BMODS is challenging Beyondprevention BMODS treatment options are limited and theyare a popular topic for future clinical explorations

Dexmedetomidine (DEX) is an 1205722-adrenergic agonistIt selectively binds to presynaptic 1205722-adrenergic receptors(1205722AR) on the locus coeruleus and decreases the levels of

norepinephrine release resulting in a reduction of postsynap-tic adrenergic activity [4] In the periphery 1205722ARs are widelydistributed in many organs including the liver kidney pan-creas blood vessels and plateletsThe administration of DEXcauses various effects in different organs [5 6] Currently theprimary clinical use of DEX is for its effects on the centralnervous system such as short-term sedation and antianxiety[7]The pharmacological actions of DEX in other organs havenot been fully evaluated in clinical patients In animal studiesDEX has been shown to reduce mortality rates and inhibitinflammatory responses in endotoxemic rats without adverseeffects on functions such as respiration [8 9] However thebenefits of applying DEX to treat postpartum BMODS inmaternity ICU patients have not been demonstrated due tothe lack of a proper animal model [10] In a pilot study ASezer et al found histopathological changes during sepsis-induced hypotension in rats [11] In another study liver andpancreatic dysfunctions were observed following the clamp-ing of the superiormesenteric artery [12] In the present studythe effects of DEX on postpartum BMODS were studied in

2 Mediators of Inflammation

rats in which BMODS was induced by the combination ofhypotension and clamping of the superior mesenteric arteryWe demonstrated that DEX administration reduced cytokinerelease and lung injury during postpartum BMODS in rats

2 Materials and Methods

21 Reagents DEX was purchased from Hospira Inc (LakeForest IL USA) For reverse transcription polymerase chainreaction (RT-PCR) analysis RNAiso Plus and Taq DNAPolymerase were purchased from Takara Biotechnology CoLtd (Dalian China) The ReverTra Ace was purchased fromToyobo Biotech Co Ltd (Shanghai China) Trizol reagentwas purchased from Invitrogen (Carlsbad CA USA)

22 Animals Sprague-Dawley (SD) rats (20 adult male and40 adult female 200ndash250 g) were purchased from the AnimalCenter of Guangdong Province The rats were housed in theGuangzhou Animal Center in accordance with the specificpathogens animals standard with a 12 hr lightdark cycle Theroom temperaturewasmaintained at 22plusmn1∘CThe rats had adlibitum access to food and drinking waterThe animal studiesin the present experiment were approved by the Animal Useand Care Committee of Guangzhou Medical University Therats were handled following the National Institutes of Healthguidelines

23 Experimental Groups The male and female (1 2) ratswere allowed to mate in the cage until the females were preg-nant as determined by detecting sperm in vaginal secretionsusing microscopy at which point the females were separatedfrom the males until delivery Postpartum female rats wereusedwithin 24 hours after delivery A total of 40 experimentalfemale rats were randomly assigned into four groups with 10rats per group as follows

The Sham (S) group catheters were placed in the rightfemoral artery and the left femoral vein

S+C group bleeding-induced hypotension andclamping of the superior mesenteric artery wereperformedS+C+D25 group administration of DEX (25120583gkgh) [13] to S+C ratsS+C+D50 group administration of DEX (50 120583gkgh) [13] to S+C rats

24 Experiment For the S group the rats were anesthetizedby the intraperitoneal administration of 10 hydration chlo-rine aldehyde (04mL100 g) The rats were then placedsupinely on an animal surgical table with a heating pad Thebody temperature was maintained at 36ndash38∘C throughoutthe experiment To monitor blood pressure a polyethylenecatheter (PE-50) was inserted into the right femoral arteryand connected to a blood pressure monitor Another PE-50was inserted into the left femoral vein for DEX administra-tion All of the catheters used in the present experiment wereprepared with heparin to prevent blood clotting For the S+Cgroup hypotension was induced by drawing blood from the

right femoral artery into a glass syringe that was preloadedwith heparin for temporary storage until the mean arterialpressure (MAP) reached the target level of 45ndash50mmHg[14] The MAP was constantly maintained at this low bloodpressure level for 60min by the withdrawal or reinfusionof storage blood via the right femoral artery Thus artificialbleeding and hypotensionwere established in the postpartumrats Resuscitation was performed by re-infusing the fullamount of blood that was previously taken from the rats torestore normal blood pressure After a normal blood pressurewasmaintained formore than 30min the abdomen of the ratwas opened under sterile conditionsThe superiormesentericartery was clamped for 60min and then released For theS+C+D25 and 50 groups dexmedetomidine (25 120583gkghand 50120583gkgh resp) was administered via the left femoralvein for 4 hours

After the previous experiment the abdominal incisionwas sutured and the catheters were removed The rats wereplaced back in the cage and freely allowed to reach for foodand drinking water The rats were sacrificed 24 hours afterthe experiment A 05-mL blood sample was taken fromthe abdominal aorta for immediate arterial blood gas levelmeasurement Another 07mL of blood was taken for bio-chemical analysis The left lung was harvested immediatelysnap frozen in liquid nitrogen and stored in the freezer forlater histological and cytokine analyses

The changes in pulmonary liver and kidney functionswere evaluated inBMODS-induced rats bymeasuring arterialblood gas aminotransferase (AST) alanine aminotransferase(ALT) total bilirubin (TBIL) blood urea nitrogen (BUN)creatinine and creatine phosphokinase (CPK) Morpholog-ical changes in the lung were evaluated using the index ofquantitative assessment of histological lung injury (IQA) andalveolar interval thickness (AIT) [15 16] Histological sec-tions from the lung were examined under the 200X powerfield Lung injurywas considered to be the presence of alveoli-containing erythrocytes or two or more neutrophilsThe per-centage of injured alveoli was counted from each field TheIQA was the mean percentage of injured alveoli from the200Xpower fieldTheAIT from the lungwas examined underthe 200X power field using the IMS image analysis system(ShenTeng Information Technology Co Ltd Shanghai)Six fields were randomly selected from each power fieldand examined making sure to avoid the bronchial andblood vessels Six alveoli were randomly selected from eachfield for thickness measurements The AIT was the meanthickness of the alveoli [15]

25 Reverse Transcription Polymerase Chain Reaction (RT-PCR) RT-PCR was performed on tissue from the leftlung Total RNA was purified using the TRIzol kit (TakaraCo Ltd) Residual genomic DNA was removed by incuba-tion with RNase-free DNase For the first strand cDNA syn-thesis RNA (2 120583g) was converted to cDNA using superscriptII reverse transcriptase (Invitrogen) The reaction mixturewas inactivated by heating to 70∘C for 15min One microliterof reaction mixture was amplified by Taq DNA polymerase(Takara Co Ltd) in a thermal cycler (GeneAmp PCRsystem 2700 Applied Biosystems Foster City CA USA)The first incubation was performed at 94∘C for 3min for

Mediators of Inflammation 3

Table 1 Effects of DEX administration in liver kidney functions during postpartum BMODS in rats

Group ALT (IUL) TBIL (umolL) BUN (mmolL) Cr (umolL) AST (IUL) CPK (IUL)Sham 461 plusmn 94 112 plusmn 19 26 plusmn 08 489 plusmn 47 1683 plusmn 352 21034 plusmn 10456S+C 3837 plusmn 1348Δ 566 plusmn 49Δ 55 plusmn 27Δ 1966 plusmn 219Δ 6113 plusmn 2161Δ 96863 plusmn 18765Δ

S+C+D25 3786 plusmn 1393Δ 521 plusmn 69Δ 52 plusmn 25Δ 1976 plusmn 236Δ 5801 plusmn 2300Δ 95970 plusmn 18794Δ

S+C+D50 3761 plusmn 1405Δ 535 plusmn 59Δ 55 plusmn 21Δ 1959 plusmn 224Δ 6014 plusmn 2063Δ 96283 plusmn 18977ΔΔCompared to the Sham group 119875 lt 005 compared to the S+C group 119875 lt 005

initial denaturation and the following steps were repeated 30times 30 s at 95∘C (denaturation) 1min (specific annealingtemperature for each primer) and 1min at 72∘C (extension)The final incubation was at 72∘C for 5min (final extension)The sequences for the primers used in the present study areas follows IL-4 sense 51015840-TCCTTCACGGCAACAAGG-AAC-31015840 and antisense 51015840-GTGAGTTCAGACCGCTGACA-31015840 (predicted size 168 bp annealing temperature 50∘C) IFN-120574 sense 51015840-GAACTGGCAAAAGGACGGTA-31015840 and anti-sense 51015840-GGATCTGTGGGTTGTTCACC-31015840 (predicted size215 bp annealing temperature 49∘C)ThePCRproducts weresize-fractioned by 1 agarose gel electrophoresis After stain-ing with ethidium bromide the amplified DNA bands wereanalyzed with the image analysis software ScionImage (ScionCorp Frederick MD USA)

26 Statistical AnalysisThe statistical analysis was performedusing Statistical Package from Social Sciences (SPSS) version130 for Windows All data were expressed as the mean plusmn SDTheMann-Whitney119880 and1205942 tests were used for the statisticalanalysis of the data among all the groups 119875 lt 005 was con-sidered to be statistically significant

3 Results

31 Effects of DEX on Liver and Kidney Dysfunctions SerumAST ALT BIL BUN Cr and CPK were measured in thegroups of 24 hours postpartum rats with BMODS (Table 1)There were significantly (119875 lt 005) increased levels of ASTALT TBIL BUN Cr and CPK in the S+C S+C+D25 andS+C+D50 groups in comparison to the Sham group indicat-ing impaired liver and kidney functions in the postpartumrats with BMODS There were no statistically significantdifferences (119875 gt 005) between the S+C and S+C+D25groups the S+C and S+C+50 groups and the S+C+D25 andS+C+50 groups suggesting that DEX administration doesnot prevent liver and kidney damage in postpartum rats withBMODS

32 Arterial Blood Gas (ABS) Analysis ABS including thepotential of hydrogen (pH) partial pressure of carbondioxidein arterial blood (PaCO2) partial pressure of oxygen inarterial blood (PaO2) and base excess (BE) was measuredin postpartum rats with BMODS (Table 2) There were sig-nificant differences (119875 lt 005) between the Sham S+C andS+C+D2550 in the levels of PaCO2 PaO2 and BE indi-cating impaired pulmonary function in postpartum rats withBMODS There was no significant difference (119875 gt 005)

between S+C and S+C+D25 or between S+C and S+C+D50suggesting that DEX administration does not improveABS inpostpartum rats with BMODS

33 Cytokine mRNA Expression The mRNA expression ofIFN-120574 and IL-4 in the lung tissue of the S+C group wassignificantly (119875 lt 005) higher than in that of the Shamgroupindicating that an inflammatory response was elicited inpostpartum rats with BMODS The IFN-120574 IL-4 and IFN-120574IL-4 mRNA ratios were significantly lower in S+C+D25and S+C+D50 than in S+C indicating reduced IFN-120574 andIL-4 release upon DEX administration during postpartumBMODS There were no statistically significant differences(119875 gt 005) in IFN-120574 IL-4 and IFN-120574IL-4 mRNA expres-sions between S+C+D25 and S+C+D50 (Table 3)

34 Morphological Evaluation of Lung Injury In comparisonto the Sham group (Figure 1(a)) lung sections from the S+Cgroup (Figure 1(b)) showed acute injury the interstitium wasexpanded by edema and inflammatory infiltrates that werecomposed of neutrophils lymphocytes and histiocytes Thealveoli were congestive and hemorrhagic Some of the alveoliwere collapsedThe epithelium was edematous and displayeda loss of cilia The IQA and AIT were significantly higher inthe S+C group compared to the Sham group (119875 lt 005) TheS+C+D25 and S+C+D50 groups showed less severe injury ascompared to the S+C group with significantly lower IQA andAIT values (119875 lt 005) (Figure 1(c)) No significant differenceswere detected between the S+C+D25 and S+C+D50 groups(Table 4)

4 Discussion

In addition to treatment for sedation and antianxiety [17]DEX has been administered to hypertensive patients duringsurgery [18] suggesting a relaxing effect on peripheral vesselsDEX exerts its effects via the selective activation of 1205722AR1205722AR is distributed not only in the central and peripheralnervous system but also in multiple organ systems where itexerts its effects on different physiological and pathologicalprocesses For example the clinical use of DEX has becomepopular in neurosurgery and heart surgery under extracor-poreal circulation anesthesia [19 20] However the effects ofDEX on BMODS have not yet been evaluated

A small number of animal models are available for stud-ying the pathogenesis of BMODS but treatments have beenlargely unsuccessful especially in patients with postpartumBMODS It is difficult to study BMODS in human subjects


Table 2 Effects of DEX administration on arterial blood gas during postpartum BMODS in rats

Group PH PaCO2 (mmHg) PaO2 (mmHg) BE (mmolL)Sham 740 plusmn 004 355 plusmn 42 922 plusmn 125 minus10 plusmn 05S+C 735 plusmn 007 437 plusmn 53Δ 656 plusmn 138Δ minus52 plusmn 04Δ

S+C+D25 732 plusmn 008 443 plusmn 45Δ 645 plusmn 145Δ minus48 plusmn 06Δ

S+C+D50 731 plusmn 007 435 plusmn 48Δ 658 plusmn 148Δ minus50 plusmn 07ΔΔCompared to the Sham group 119875 lt 005 compared to the S+C group 119875 lt 005

(a) Sham (200X) (b) S+C (200X) (c) S+C+D25 (200X)

Figure 1 Histological sections from the lung were examined under the 200X power fieldThe IQAwas themean percentage of injured alveolifrom the 200X power field The AIT was examined under the 200X power field using the IMS image analysis system (ShenTeng InformationTechnology Co Ltd Shanghai) The AIT was the mean thickness of the alveoli

Table 3 Effects of DEX administration on IFN-120574 IL-4 and IFN-120574IL-4 mRNA expression during postpartum BMODS in rats

Group IFN-120574 IL-4 IFN-120574IL-4Sham 2734 plusmn 156 2338 plusmn 201 107 plusmn 004S+C 3451 plusmn 325Δ 3235 plusmn 236Δ 106 plusmn 003Δ

S+C+25 2027 plusmn 168Δ 2424 plusmn 202 083 plusmn 002Δ

S+C+50 1906 plusmn 210Δ 2236 plusmn 131 085 plusmn 003ΔΔCompared to the Sham group 119875 lt 005 compared to the S+C group 119875 lt005

Table 4 The index of quantitative assessment of lung (IQA) andalveolar interval thickness (AIT)

Group IQA () AIT (120583m)Sham 1345 plusmn 384 69 plusmn 14S+C 4045 plusmn 424Δ 155 plusmn20Δ

S+C+D25 3067 plusmn 367Δ 102 plusmn 23Δ

S+C+D50 2885 plusmn 345Δ 98 plusmn 22ΔΔCompared to the Sham group 119875 lt 005 compared to the S+C group 119875 lt005

because there are many factors involved in the pathogenesisand because there are a wide range of clinical presentations[21] Therefore the development of a successful animalmodel is a priority In the present study we establisheda BMODS model in postpartum rats This animal modelnot only mimics postpartum bleeding-induced shock butit also mimics reperfusion injury and endotoxicity Themajority of animal models for MODS are created by theexternal administration of endotoxin to induce hypotension[22] Due to the wide range of individual sensitivities to

endotoxin many animals showed either a response too mildto induce hypotension or a response too strong resulting indeath of the animal The level of hypotension and thereforethe degree of injury are difficult to keep constant acrossgroups In the present study hypotension was artificiallycontrolled during the experiment The time of clampingof the superior mesenteric artery was kept equal acrossthe groups Therefore the level of damage was constantacross the groups The clamping of the superior mesentericartery provided an ischemic and reperfusion process Thisprocess induced endotoxin release rather than requiringexternal administration Together with constant hypotensionin rats our animal model provides a reliable and constantlevel of damage across all groups for the study of BMODSOur current BMODS model induced reperfusion injuryWe observed inflammatory cytokine release in response toshock Furthermore clamping of the superior mesentericartery induced multiple organ dysfunction syndrome andit did not induce inflammatory cytokine release simply dueto uncontrolled hemorrhagic shock inflammatory cytokinerelease simply due to uncontrolled hemorrhagic shock differsfrom the response observed in patients undergoing postpar-tum hypotensive shock Free radicals calcium overload andincreased leukocytes play important roles in the process ofischemia-reperfusion injury However vasoactive peptidesregulatory peptides inflammatory mediators damaged cellsand metabolism also play important roles in the shockprocess The results in present study showed that DEXadministration decreased inflammatory cytokine release anddamage in the lung in our currentmodel of BMODS-inducedreperfusion injuryThe results showed that DEXmay preventorgan damage through the inhibition of inflammation andfree radical release from leukocytes The specific mechanism


of action of DEX in the BMODS model needs furtherresearch According to the diagnosis criteria of MODS dam-age of two or more organs must occur at the same time orsequentially within 24 hours of induction by pathogenicfactors Therefore we sacrificed all of the rats 24 hours afterthe experiment Liver kidney and lung dysfunctions wereevident in the S+Cgroup in the present study (Tables 1 and 2)However there were no statistically significant differencesbetween the S+C and S+C+D25 groups S+C and S+C+50groups and S+C+D25 and S+C+50 groups suggesting thatDEX administration did not prevent liver and kidney damagein postpartum rats with BMODS Several variables mayexplain these results including that the time of DEX admin-istration was too short the specimen collection was too early(24 hours) or the dose of DEX administration was not suit-able for use At later time points of BMODS biochemicalmarkers may be more obviously altered and increases ininflammatory cytokine release may be more apparentThere-fore DEX administration may more clearly reduce biochem-ical markers and inflammatory cytokines at later time points

There have been several hypotheses regarding the mech-anism of MODS (Figure 2) including ischemia reperfusioninflammation intestinal bacteria toxin shifts two strikesdouble preexcitation syndrome and stress genes Howevernone of these theories can fully explain the pathogenesis ofMODS The effects of DEX on the pathogenesis of MODSremain unclear Regardless the effect of DEX on inhibitingcytokine release was confirmed in this study CD4+ T helpercells are divided intoTh1 andTh2 subsets based on the cytok-ines they secrete [23] Cytokines play an important role inlymphocyte development maturation differentiation andactivationTh1 cells mainly secrete interleukin-2 (IL-2) IFN-120574 and tumor necrosis factor-120572 (TNF-120572) They mediate cellu-lar immunity and participate in late onset allergic reactionsand inflammation Th2 cells secrete IL-4 IL-5 IL-6 IL-9IL-10 and IL-13 and are responsible for B lymphocyteproliferation antibody production immune tolerance andhumoral immunity [24 25]Therefore IFN-120574 and IL-4 are thebest respective markers for Th1 and Th2 cells and they werechosen to evaluate the changes in immune function in post-partum rats with BMODS in the present study DEX has beenshown to inhibit cytokine secretion in many studies Somereports have shown that DEX decreases cytokine secretionafter endotoxin injection [26] Other reports have demon-strated that DEX inhibits cytokine release in rats followingendotoxin administration [22] In mice DEX administrationled to a decrease in the total number of lung inflammatorycells a reduction in the concentration of macrophage inflam-matory protein-2 (MIP-2) and interleukin-120573 (IL-120573) and adecrease in the ratio of drywet tissue in the lung [27] To datethe mechanism underlying the role of DEX in the reductionof cytokine secretion is still a matter of debate One groupreported thatDEX administration led to a reduced inflamma-tory response during the treatment of spinal cord injury con-firming the anti-inflammatory effects of DEX [28] Anothergroup reported that DEX protected nerve tissue from reper-fusion-induced injury after -erm brain ischemia via reducedlevels of TNF-120572 and decreased numbers of degenerative neu-rons in the hippocampus anddentate gyrus [29]Our findings

Ischemiareperfusion

Inflammation

Intestinalbacteria toxin

shift

Two strikes doublepreexcitation

syndrome

Stress gene

MODSDEX

Figure 2 There have been several hypotheses regarding themechanism of MODS (Figure 2) including ischemia reperfusioninflammation intestinal bacteria toxin shifts two strikes doublepreexcitation syndrome and stress genes

in the present study showed that DEX had strong anti-inflammatory effects on postpartum rats with BMODS Asshown in the S+C+D25 and S+C+D50 groups DEX admin-istration significantly reduced IFN-120574 and IL-4 Because bothIFN-120574 and IL-4 represent humoral and cellular immunitythese findings suggested that both immune pathways weresuppressed by DEX Further a decrease in the IFN-120574IL-4ratio suggested that DEX suppressed cellular immunity morethan humoral immunity There are few reports regarding amechanism of DEX at the cellular level Lower malondialde-hyde (MDA) and nitric oxide (NO) levels and higher super-oxide dismutase (SOD) and catalase (CAT) were observedin the hippocampus during reperfusion-induced injury inthe ischemic rat brain after DEX administration [30] DEXinhibited lipid peroxidation of the cell membrane in ischemiareperfusion models [31ndash33] Further studies are required toaddress this issue in our model Decreased immune function(both cellular and humoral) may induce septic shock How-ever DEX administration did not lead to septic shock in ourBMODSmodel and this was confirmed by a report that DEXadministration in early-stage sepsis patients decreased themortality rate [27]

The decrease in cytokine release upon DEX treatmentmay protect organs from ischemic injuries Clinically DEXadministration in combinationwith ketamine reducedmech-anical ventilation-induced injury and inflammation in thelungs of endotoxemic rats [27] In an animal model for spinalcord injury the administration of DEX decreased edema andhemorrhage in gray matter without changing the numberof neurons [34] In the present study DEX administrationreduced inflammatory infiltration and edema in the lungalthough no significant improvements were observed in ABSor liver and kidney function This finding may provide abasis for additional management options for patients withBMODS In current practice BMODS patients are treatedwithmechanical approaches to prevent lung injury includingreducing the tidal volume of mechanical ventilation and pos-itive pressure ventilation at the end of breath [35] Howeverseveral studies have explored the combination of DEX andketamine [36]

In summary the present study demonstrated that DEXadministration reduced IFN-120574 and IL-4 release anddecreased


lung injury during postpartum BMODS It is possible thatDEX administration decreased inflammatory cytokine pro-duction in BMODS by inhibiting inflammation and freeradical release by leukocytes independent of the DEX dose

Acknowledgments

The authors thank Liu Zhengzhuan for his assistance Thiswork was supported by the Youth Foundation of GuangzhouMedicalUniversity China Grant no 2012A10 and the Scienceand Technology Foundation of Guangdong Province ChinaGrant no 2012B020700007

References

[1] A Lalonde B A Daviss A Acosta and K Herschderfer ldquoPost-partum hemorrhage today ICMFIGO initiative 2004ndash2006rdquoInternational Journal of Gynecology and Obstetrics vol 94 no3 pp 243ndash253 2006

[2] S L ClarkMA Belfort G ADildyMAHerbst J AMeyersand G D Hankins ldquoMaternal death in the 21st century causesprevention and relationship to cesarean deliveryrdquo AmericanJournal of Obstetrics and Gynecology vol 199 no 1 pp 361ndash3652008

[3] M Levi ldquoDisseminated intravascular coagulation (DIC) inpregnancy and the peri-partum periodrdquo Thrombosis Researchvol 123 pp S63ndashS64 2009

[4] L Quintin and M Ghignone ldquoRisks associated with perioper-ative use of alpha-2 adrenoceptors agonistsrdquo in Alpha-2 Adren-oceptor Agonists in Anaesthesia and Intensive Care pp 347ndash368Harcourt London UK 2000

[5] A Aslan M Cemek O Eser et al ldquoDoes dexmedetomidinereduce secondary damage after spinal cord injury An exper-imental studyrdquo European Spine Journal vol 18 no 3 pp 336ndash344 2009

[6] C A Fairbanks K F Kitto H O Nguyen L S Stone and GLWilcox ldquoClonidine and dexmedetomidine produce antinoci-ceptive synergy in mouse spinal cordrdquo Anesthesiology vol 110no 3 pp 638ndash647 2009

[7] D B Coursin D B Coursin and G A Maccioli ldquoDexmedeto-midinerdquo Current Opinion in Critical Care vol 7 no 4 pp 221ndash226 2001

[8] T Taniguchi Y Kidani H Kanakura Y Takemoto and K Yam-amoto ldquoEffects of dexmedetomidine on mortality rate andinflammatory responses to endotoxin-induced shock in ratsrdquoCritical Care Medicine vol 32 no 6 pp 1322ndash1326 2004

[9] J W Suliburk K S Helmer E A Gonzalez E K Robinsonand D W Mercer ldquoKetamine attenuates liver injury attributedto endotoxemia role of cyclooxygenase-2rdquo Surgery vol 138 no2 pp 134ndash140 2005

[10] M J Sheen and SHo ldquoDexmedetomidinemore than a sedativeand analgesicrdquo Acta Anaesthesiologica Taiwanica vol 46 no 4pp 149ndash150 2008

[11] A SezerDMemis UUsta andN Sut ldquoThe effect of dexmedet-omidine on liver histopathology in a rat sepsis model an exper-imental pilot studyrdquo Ulusal Travma ve Acil Cerrahi Dergisi vol16 no 2 pp 108ndash112 2010

[12] D G Farmer B Ke X Shen et al ldquoInterleukin-13 protectsmouse intestine from ischemia and reperfusion injury throughregulation of innate and adaptive immunityrdquo Transplantationvol 91 no 7 pp 737ndash743 2011

[13] C L Yang P S Tsai and C J Huang ldquoEffects of dexmedetomi-dine on regulating pulmonary inflammation in a rat model ofventilator-induced lung injuryrdquo Acta Anaesthesiologica Taiwan-ica vol 46 no 4 pp 151ndash159 2008

[14] S Huang P Tsai and C Huang ldquoDexmedetomidine-ketaminecombination mitigates pulmonary type-2 cationic amino acidtransporter isozymes upregulation in hemorrhagic shock ratsrdquoActa Anaesthesiologica Taiwanica vol 48 no 3 pp 110ndash1162010

[15] S-Q Chen Y-B Zhang C-C Li et al ldquoAntenatal exposure todifferent doses of dexamethasone leads to delayed alveolariza-tion in newborn ratsrdquo Chinese Journal of Pantophysiology vol27 no 2 pp 343ndash349 2011

[16] Y Y Dai X X Qiu Y Wang et al ldquoEffect of hydroxysafflor yel-low A on mitochondrial permeability transition in pneumono-cytes after ischemiareperfusion injure in ratsrdquo Chinese Journalof Pathophysiology vol 27 no 6 pp 1180ndash1186 2011

[17] J R Cormack R M Orme and T G Costello ldquoThe role of 1205722-agonists in neurosurgeryrdquo Journal of Clinical Neuroscience vol12 no 4 pp 375ndash378 2005

[18] A Koroglu H Teksan O Sagir A Yucel H I Toprak and OM Ersoy ldquoA comparison of the sedative hemodynamic andrespiratory effects of dexmedetomidine and propofol in chil-dren undergoing magnetic resonance imagingrdquo Anesthesia andAnalgesia vol 103 no 1 pp 63ndash67 2006

[19] S Mimuro T Katoh A Suzuki et al ldquoDeterioration of myocar-dial injury due to dexmedetomidine administration after myo-cardial ischaemiardquo Resuscitation vol 81 no 12 pp 1714ndash17172010

[20] J C Drummond and M K Sturaitis ldquoBrain tissue oxygenationduring dexmedetomidine administration in surgical patientswith neurovascular injuriesrdquo Journal of Neurosurgical Anesthe-siology vol 22 no 4 pp 336ndash341 2010

[21] S E Geller M G Adams P J Kelly B S Kodkany and R JDerman ldquoPostpartum hemorrhage in resource-poor settingsrdquoInternational Journal of Gynecology and Obstetrics vol 92 no3 pp 202ndash211 2006

[22] T Taniguchi A Kurita K Kobayashi K Yamamoto and HInaba ldquoDose- and time-related effects of dexmedetomidine onmortality and inflammatory responses to endotoxin-inducedshock in ratsrdquo Journal of Anesthesia vol 22 no 3 pp 221ndash2282008

[23] S A Rosenberg N P Restifo J C Yang R A Morgan and ME Dudley ldquoAdoptive cell transfer a clinical path to effectivecancer immunotherapyrdquo Nature Reviews Cancer vol 8 no 4pp 299ndash308 2008

[24] O Akbari P Stock E Meyer et al ldquoEssential role of NKTcells producing IL-4 and IL-13 in the development of allergen-induced airway hyperreactivityrdquo Nature Medicine vol 9 no 5pp 582ndash588 2003

[25] B Spellberg and J E Edwards Jr ldquoType 1type 2 immunity ininfectious diseasesrdquo Clinical Infectious Diseases vol 32 no 1pp 76ndash102 2001

[26] J Szelenyi J P Kiss and E S Vizi ldquoDifferential involvementof sympathetic nervous system and immune system in themodulation of TNF-120572 production by 1205722- and 120573-adrenoceptorsin micerdquo Journal of Neuroimmunology vol 103 no 1 pp 34ndash402000

[27] C Yang C Chen P Tsai T Wang and C Huang ldquoProtec-tive effects of dexmedetomidine-ketamine combination againstventilator-induced lung injury in endotoxemia ratsrdquo Journal ofSurgical Research vol 167 no 2 pp e273ndashe281 2011


[28] M Can S Gul S Bektas V Hanci and S Acikgoz ldquoEffectsof dexmedetomidine or methylprednisolone on inflammatoryresponses in spinal cord injuryrdquo Acta Anaesthesiologica Scandi-navica vol 53 no 8 pp 1068ndash1072 2009

[29] O Eser H Fidan O Sahin et al ldquoThe influence of dexmedeto-midine on ischemic rat hippocampusrdquo Brain Research vol 1218pp 250ndash256 2008

[30] R D Sanders J Xu Y Shu et al ldquoDexmedetomidine attenu-ates isoflurane-induced neurocognitive impairment in neonatalratsrdquo Anesthesiology vol 110 no 5 pp 1077ndash1085 2009

[31] H Yagmurdur N Ozcan F Dokumaci K Kilinc F Yilmaz andH Basar ldquoDexmedetomidine reduces the ischemia-reperfusioninjury markers during upper extremity surgery with tourni-quetrdquo Journal of Hand Surgery vol 33 no 6 pp 941ndash947 2008

[32] H Okada T Kurita T Mochizuki K Morita and S SatoldquoThe cardioprotective effect of dexmedetomidine on globalischaemia in isolated rat heartsrdquo Resuscitation vol 74 no 3 pp538ndash545 2007

[33] K Engelhard CWerner E Eberspacher et al ldquoThe effect of the1205722-agonist dexmedetomidine and the N-methyl-D-aspartateantagonist S(+)-ketamine on the expression of apoptosis-reg-ulating proteins after incomplete cerebral ischemia and reper-fusion in ratsrdquo Anesthesia and Analgesia vol 96 no 2 pp 524ndash531 2003

[34] S Gul V Hanci B Bahadir et al ldquoThe effectiveness of dex-medetomidine in experimental spinal cord injury compared tomethylprednisolone in ratsrdquo Journal of Clinical Neurosciencevol 17 no 4 pp 490ndash494 2010

[35] J Kuhmonen J Pokorny R Miettinen et al ldquoNeuroprotectiveeffects of dexmedetomidine in the gerbil hippocampus aftertransient global ischemiardquoAnesthesiology vol 87 no 2 pp 371ndash377 1997

[36] N R MacIntyre ldquoVentilator-associated pneumonia the role ofventilator management strategiesrdquo Respiratory Care vol 50 no6 pp 766ndash772 2005

Submit your manuscripts athttpwwwhindawicom

Stem CellsInternational

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


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The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Immunology ResearchHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Volume 2014Hindawi Publishing Corporationhttpwwwhindawicom


rats in which BMODS was induced by the combination ofhypotension and clamping of the superior mesenteric arteryWe demonstrated that DEX administration reduced cytokinerelease and lung injury during postpartum BMODS in rats

2 Materials and Methods

21 Reagents DEX was purchased from Hospira Inc (LakeForest IL USA) For reverse transcription polymerase chainreaction (RT-PCR) analysis RNAiso Plus and Taq DNAPolymerase were purchased from Takara Biotechnology CoLtd (Dalian China) The ReverTra Ace was purchased fromToyobo Biotech Co Ltd (Shanghai China) Trizol reagentwas purchased from Invitrogen (Carlsbad CA USA)

22 Animals Sprague-Dawley (SD) rats (20 adult male and40 adult female 200ndash250 g) were purchased from the AnimalCenter of Guangdong Province The rats were housed in theGuangzhou Animal Center in accordance with the specificpathogens animals standard with a 12 hr lightdark cycle Theroom temperaturewasmaintained at 22plusmn1∘CThe rats had adlibitum access to food and drinking waterThe animal studiesin the present experiment were approved by the Animal Useand Care Committee of Guangzhou Medical University Therats were handled following the National Institutes of Healthguidelines

23 Experimental Groups The male and female (1 2) ratswere allowed to mate in the cage until the females were preg-nant as determined by detecting sperm in vaginal secretionsusing microscopy at which point the females were separatedfrom the males until delivery Postpartum female rats wereusedwithin 24 hours after delivery A total of 40 experimentalfemale rats were randomly assigned into four groups with 10rats per group as follows

The Sham (S) group catheters were placed in the rightfemoral artery and the left femoral vein

S+C group bleeding-induced hypotension andclamping of the superior mesenteric artery wereperformedS+C+D25 group administration of DEX (25120583gkgh) [13] to S+C ratsS+C+D50 group administration of DEX (50 120583gkgh) [13] to S+C rats

24 Experiment For the S group the rats were anesthetizedby the intraperitoneal administration of 10 hydration chlo-rine aldehyde (04mL100 g) The rats were then placedsupinely on an animal surgical table with a heating pad Thebody temperature was maintained at 36ndash38∘C throughoutthe experiment To monitor blood pressure a polyethylenecatheter (PE-50) was inserted into the right femoral arteryand connected to a blood pressure monitor Another PE-50was inserted into the left femoral vein for DEX administra-tion All of the catheters used in the present experiment wereprepared with heparin to prevent blood clotting For the S+Cgroup hypotension was induced by drawing blood from the

right femoral artery into a glass syringe that was preloadedwith heparin for temporary storage until the mean arterialpressure (MAP) reached the target level of 45ndash50mmHg[14] The MAP was constantly maintained at this low bloodpressure level for 60min by the withdrawal or reinfusionof storage blood via the right femoral artery Thus artificialbleeding and hypotensionwere established in the postpartumrats Resuscitation was performed by re-infusing the fullamount of blood that was previously taken from the rats torestore normal blood pressure After a normal blood pressurewasmaintained formore than 30min the abdomen of the ratwas opened under sterile conditionsThe superiormesentericartery was clamped for 60min and then released For theS+C+D25 and 50 groups dexmedetomidine (25 120583gkghand 50120583gkgh resp) was administered via the left femoralvein for 4 hours

After the previous experiment the abdominal incisionwas sutured and the catheters were removed The rats wereplaced back in the cage and freely allowed to reach for foodand drinking water The rats were sacrificed 24 hours afterthe experiment A 05-mL blood sample was taken fromthe abdominal aorta for immediate arterial blood gas levelmeasurement Another 07mL of blood was taken for bio-chemical analysis The left lung was harvested immediatelysnap frozen in liquid nitrogen and stored in the freezer forlater histological and cytokine analyses

The changes in pulmonary liver and kidney functionswere evaluated inBMODS-induced rats bymeasuring arterialblood gas aminotransferase (AST) alanine aminotransferase(ALT) total bilirubin (TBIL) blood urea nitrogen (BUN)creatinine and creatine phosphokinase (CPK) Morpholog-ical changes in the lung were evaluated using the index ofquantitative assessment of histological lung injury (IQA) andalveolar interval thickness (AIT) [15 16] Histological sec-tions from the lung were examined under the 200X powerfield Lung injurywas considered to be the presence of alveoli-containing erythrocytes or two or more neutrophilsThe per-centage of injured alveoli was counted from each field TheIQA was the mean percentage of injured alveoli from the200Xpower fieldTheAIT from the lungwas examined underthe 200X power field using the IMS image analysis system(ShenTeng Information Technology Co Ltd Shanghai)Six fields were randomly selected from each power fieldand examined making sure to avoid the bronchial andblood vessels Six alveoli were randomly selected from eachfield for thickness measurements The AIT was the meanthickness of the alveoli [15]

25 Reverse Transcription Polymerase Chain Reaction (RT-PCR) RT-PCR was performed on tissue from the leftlung Total RNA was purified using the TRIzol kit (TakaraCo Ltd) Residual genomic DNA was removed by incuba-tion with RNase-free DNase For the first strand cDNA syn-thesis RNA (2 120583g) was converted to cDNA using superscriptII reverse transcriptase (Invitrogen) The reaction mixturewas inactivated by heating to 70∘C for 15min One microliterof reaction mixture was amplified by Taq DNA polymerase(Takara Co Ltd) in a thermal cycler (GeneAmp PCRsystem 2700 Applied Biosystems Foster City CA USA)The first incubation was performed at 94∘C for 3min for








3 Results






4 Discussion























Ischemiareperfusion

Inflammation


shift


syndrome

Stress gene

MODSDEX







Acknowledgments


References











































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of























3 Results






4 Discussion























Ischemiareperfusion

Inflammation


shift


syndrome

Stress gene

MODSDEX







Acknowledgments


References











































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of




































Ischemiareperfusion

Inflammation


shift


syndrome

Stress gene

MODSDEX







Acknowledgments


References











































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of


















Acknowledgments


References











































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of































of






Disease Markers



OncologyJournal of





PPAR Research



Journal of

ObesityJournal of
















research article dexmedetomidine reduced cytokine...

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