The roles of macrophage migration inhibitory factor in retinal diseases

Macrophage migration inhibitory factor(MIF),a multifunctional cytokine,is secreted by various cells and participates in inflammatory reactions,including innate and adaptive immunity.There are some evidences that MIF is involved in many vitreoretinal diseases.For example,MIF can exacerbate many types of uveitis;measurements of MIF levels can be used to monitor the effectiveness of uveitis treatment.MIF also alleviates trauma-induced and glaucoma-induced optic nerve damage.Furthermore,MIF is critical for retinal/choroidal neovascularization,especially complex neovascularization.MIF exacerbates retinal degeneration;thus,anti-MIF therapy may help to mitigate retinal degeneration.MIF protects uveal melanoma from attacks by natural killer cells.The mechanism underlying the effects of MIF in these diseases has been demonstrated:it binds to cluster of differentiation 74,inhibits the c-Jun N-terminal kinase pathway,and triggers mitogen-activated protein kinases,extracellular signal-regulated kinase-1/2,and the phosphoinositide-3-kinase/Akt pathway.MIF also upregulates Toll-like receptor 4 and activates the nuclear factor kappa-B signaling pathway.This review focuses on the structure and function of MIF and its receptors,including the effects of MIF on uveal inflammation,retinal degeneration,optic neuropathy,retinal/choroidal neovascularization,and uveal melanoma.

Brain-derived neurotrophic factor mediates macrophage migration inhibitory factor to protect neurons against oxygen-glucose deprivation

Macrophage migration inhibitory factor(MIF)is a chemokine that plays an essential role in immune system function.Previous studies suggested that MIF protects neurons in ischemic conditions.However,few studies are reported on the role of MIF in neurological recovery after ischemic stroke.The purpose of this study is to identify the molecular mechanism of neuroprotection mediated by MIF.Human neuroblastoma cells were incubated in Dulbecco’s modified Eagle’s medium under oxygen-glucose deprivation(OGD)for 4 hours and then returned to normal aerobic environment for reperfusion(OGD/R).30 ng/mL MIF recombinant(30 ng/mL)or ISO-1(MIF antagonist;50μM)was administered to human neuroblastoma cells.Then cell cultures were assigned to one of four groups:control,OGD/R,OGD/R with MIF,OGD/R with ISO-1.Cell viability was analyzed using WST-1 assay.Expression levels of brain-derived neurotrophic factor(BDNF),microtubule-associated protein 2(MAP2),Caspase-3,Bcl2,and Bax were detected by western blot assay and immunocytochemistry in each group to measure apoptotic activity.WST-1 assay results revealed that compared to the OGD/R group,cell survival rate was significantly higher in the OGD/R with MIF group and lower in the OGD/R with ISO-1 group.Western blot assay and immunocytochemistry results revealed that expression levels of BDNF,Bcl2,and MAP2 were significantly higher,and expression levels of Caspase-3 and Bax were significantly lower in the MIF group than in the OGD/R group.Expression levels of BDNF,Bcl2,and MAP2 were significantly lower,and expression levels of Caspase-3 and Bax were significantly higher in the ISO-1 group than in the OGD/R group.MIF administration promoted neuronal cell survival and induced high expression levels of BDNF,MAP2,and Bcl2(anti-apoptosis)and low expression levels of Caspase-3 and Bax(pro-apoptosis)in an OGD/R model.These results suggest that MIF administration is effective for inducing expression of BDNF and leads to neuroprotection of neuronal cells against hypoxic injury.

Early treadmill exercise increases macrophage migration inhibitory factor expression after cerebral ischemia/reperfusion

The neuroprotective function of macrophage migration inhibitory factor(MIF) in ischemic stroke was rarely evaluated.This study aimed to investigate the effects of early treadmill exercise on recovery from ischemic stroke and to determine whether these effects are associated with the expression levels of MIF and brain-derived neurotrophic factor(BDNF) in the ischemic area.A total of 40 male Sprague-Dawley rats were randomly assigned to the ischemia and exercise group [middle cerebral artery occlusion(MCAO)-Ex,n = 10),ischemia and sedentary group(MCAO-St,n = 10),sham-surgery and exercise group(Sham-Ex,n= 10),or sham-surgery and sedentary group(Sham-St,n = 10).The MCAO-Ex and MCAO-St groups were subjected to MCAO for 60 minutes,whereas the Sham-Ex and Sham-St groups were subjected to an identical operation without MCAO.Rats in the MCAO-Ex and Sham-Ex groups then ran on a treadmill for 30 minutes once a day for 5 consecutive days.After reperfusion,the hanging time tested by the wire hang test was longer and the relative fractional anisotropy determined by MRI was higher in the peri-infarct region of the MCAO-Ex group compared with the MCAO-St group.The expression levels of MIF and BDNF in the peri-infarct region were upregulated in the MCAO-Ex group.Increased MIF and BDNF levels were positively correlated with relative fractional anisotropy changes in the peri-infarct region.There was no significant difference in the levels of MIF and BDNF in the peri-infarct region between the Sham-Ex and Sham-St groups.Our study demonstrated that early exercise(initiated 48 hours after the MCAO) could improve motor and neuronal recovery after ischemic stroke.Furthermore,the increased levels of MIF and BDNF in the peri-infarct region(penumbra) may be one of the mechanisms of enhanced neurological function recovery.All experiments were approved by the Institutional Animal Care and Use Committee in Asan Medical Center in South Korea(2016-12-126).

Macrophage migration inhibitory factor as a potential prognostic factor in gastric cancer

AIM:To investigate macrophage migration inhibitory factor(MIF) expression and its clinical relevance in gastric cancer,and effects of MIF knockdown on proliferation of gastric cancer cells. METHODS:Tissue microarray containing 117 samples of gastric cancer and adjacent non-cancer normal tissues was studied for MIF expression by immunohistochemistry(IHC) semiquantitatively,and the association of MIF expression with clinical parameters was analyzed. MIF expression in gastric cancer cell lines was detected by reverse transcriptionpolymerase chain reaction(RT-PCR) and Western blot. Two pairs of si RNA targeting the MIF gene(MIF si-1 and MIF si-2) and one pair of scrambled si RNA as a negative control(NC) were designed and chemically synthesized. All si RNAs were transiently transfected in AGS cells with OligofectamineTM to knock down the MIF expression,with the NC group and mock group(OligofectamineTM alone) as controls. At 24,48,and 72 h after transfection,MIF m RNA was analyzed by RTPCR,and MIF and proliferating cell nuclear antigen(PCNA) proteins were detected by Western blot.The proliferative rate of AGS cells was assessed by methylthiazolyl tetrazolium(MTT) assay and colony forming assay.RESULTS:The tissue microarray was informative for IHC staining,in which the MIF expression in gastric cancer tissues was higher than that in adjacent noncancer normal tissues(P < 0.001),and high level of MIF was related to poor tumor differentiation,advanced T stage,advanced tumor stage,lymph node metastasis,and poor patient survival(P < 0.05 for all). After si RNA transfection,MIF m RNA was measured by real-time PCR,and MIF protein and PCNA were assessed by Western blot analysis. We found that compared to the NC group and mock group,MIF expression was knocked down successfully in gastric cancer cells,and PCNA expression was downregulated with MIF knockdown as well. The cell counts and the doubling times were assayed by MTT 4 d after transfection,and colonies formed were assayed by colony forming assay 10 d after transfection; all these showed significant changes in gastric cancer cells transfected with specific si RNA compared with the control si RNA and mock groups(P < 0.001 for all).CONCLUSION:MIF could be of prognostic value in gastric cancer and might be a potential target for small-molecule therapy.

Serum and ascites levels of macrophage migration inhibitory factor, TNF-α and IL-6 in patients with chronic virus hepatitis B and hepatitis cirrhosis

Objective: To study the potential role of macrophage migration inhibitory factor (MIF), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the development of chronic virus hepatitis B (CH) and hepatitis cirrhosis (HC). Methods: The serum concentrations of MIF, TNF-α and IL-6 in 18 patients with chronic virus hepatitis B and in 14 patients with hepatitis cirrhosis without as- citic fluid, and the serum and ascites cytokine con- centrations in 22 HC patients with ascitic fluid were detected by enzyme linked immunity sorbed assay. Results: The cytokine concentrations of the patients were significantly higher than those of the controls. The serum levels of MIF, TNF-α and IL-6 of the 22 patients with ascitic fluid were higer than those of 14 HC patients without ascites. In the 18 patients with CH, the serum cytokine concentrations were the low- est. The serum cytokine concentrations of the 22 HC patients with ascites were significantly higher than those of the 14 HC patients without ascites (P< 0. 01). Their serum cytokine concentrations were sig- nificantly higher than those in the 18 patients with CH (P<0. 01). The concentration of IL-6 in ascites was the highest among all the groups. The serum le- vels of MIF, TNF-α and IL-6 are correlated with al- anine aminotransferase (ALT) in the patients with CH, but not in those with HC with or without asci- tes. Conclusions: These results indicated that MIF, TNF- α and IL-6 may participate in the pathological process of CH and cirrhosis, that IL-6 seems to play an important role in ascites formation, and that se- rum levels of MIF, TNF-α and IL-6 appear to reflect the severity of tissue injury in HBV disease.

Cloning and mRNA expression of macrophage migration inhibitory factor (MIF) gene of large yellow croaker (P seudosciaena crocea)

Mammalian macrophage migration inhibitory factor （MIF） plays an important role as an indispensable mediator in the pathogenesis of inflammatory disease like septicemia, but little is known about the role of MIF homologue in fish septicemia. The authors have cloned the MIF homologue in large yellow croaker Pseudosciaena crocea （LycMIF） using RACE approach. The full-length cDNA of LycMIF was 634 bases and contained an ORF of 345 bases encoding a protein of 115 amino acid residues. As demonstrated by RT-PCR and QRT-PCR assay, MIF mRNAs were constitutively expressed in 11 selected tissues and were abundant in brain and liver. Moreover, the LycMIF transcripts in the liver and head kidney were responsive to bacteria infection and could be significantly up-regulated. Our results provide the first direct evidence that fish MIF was implicated in pathogenesis of fish vibrosis and play an important role in response to bacteria infection.

Upregulation of macrophage migration inhibitory factor and calgizzarin by androgen in TM4 mouse Sertoli cells

Aim： To identify proteins induced by androgen in Sertoli cells during spermatogenesis. Methods： We analyzed protein profiles in TM4 Sertoli cells treated with dihydrotestosterone （DHT） using surface enhanced laser desorption ionization time-of-flight mass spectrometry （SELDI-TOF-MS）. Results： We found increases in the expression of a 5.0-kDa protein at 15 min, an 11.3-kDa protein at 24 h and 4.3 kDa, 5.7 kDa, 5.8 kDa, 9.95 kDa and 9.98 kDa proteins at 48 h after the treatment. In contrast, the expression of 6.3 kDa and 8.6 kDa proteins decreased at 30 min, and 4.9 kDa, 5.0 kDa, 12.4 kDa and 19.8 kDa proteins at 48 h after the treatment. The ll.3-kDa protein was identified as macrophage migration inhibitory factor （MIF） known to having various functions. The 9.98-kDa protein was identified as calgizzarin related to calcium channels. The timing of their expression suggests that MIF and calgizzarin are involved in late regulation of spermatogenesis in Sertoli cells by androgen. Conclusion： MIF and calgizzarin are two important androgen-responsive proteins produced by Sertoli cells and they might play a role in regulating spermatogenesis.

Expression of macrophage migration inhibitory factor in Aspergillus fumigatus keratitis

AIM: To investigate the expression of macrophage migration inhibitory factor(MIF) and detect its role in the innate immune response of fungal keratitis(FK). METHODS: We collected the paraffin-embedded cornea tissues from 10 FK and 6 ocular trauma patients to explore the MIF expression by immunohistochemistry. Then we cultured telomease-immortalized human corneal epithelial cells(THCEs), stimulated by the hyphae suspension of Aspergillus fumigatus(A. fumigatus) to detect the change of MIF with or without the pretreatment of MIF inhibitor [4-Iodo-6-phenylpyrimidine(4-IPP)] by real-time polymerase chain reaction(PCR). The protein level of MIF was also tested by immunohistochemistry, and the level of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) mRNA were compared between normal, hyphae stimulated and 4-IPP pretreated groups by real-time PCR to study the influence of MIF on the expression of TNF-α and IL-6. Corneal severity of rats' FK models was documented by clinical scores, and real-time PCR. Western blot and immunohistochemistry were used to test the expression of MIF, TNF-α and IL-6 in rats' corneas.RESULTS: In the corneas of FK patients, there was much stronger expression of MIF than that in the normal group showed by immunohistochemistry. In cultured THCEs stimulated by A. fumigatus, the expression of MIF became stronger in both immunohistochemistry and PCR at 16, 24, 32 and 48 h post infection(p.i.; P<0.01, P<0.01, P<0.01, P<0.05). After pretreated with 4-IPP, the expression of MIF reduced at 4, 8, 16 h p.i.(P<0.05, P<0.05, P<0.05) and the downstream TNF-α and IL-6 decreased obviously(P<0.05, P<0.01). In rats with A. fumigatus keratitis, the relative mRNA and protein level of MIF increased than thosein the normal group by PCR(at 1 d: P<0.01, 3 d: P<0.01, 5 d: P<0.01), Western blot and immunohistochemistry. After blocked MIF with 4-IPP, the clinical outcomes of rat keratitis showed markedly reduced inflammatory response(P<0.01), with TNF-α and IL-6 decreased in accordance with those in THCEs by PCR(P<0.05, P<0.01). CONCLUSION: The expression of MIF increased significantly in FK patients, THCEs and rats stimulated by A. fumigatus. After blocked with 4-IPP, the expression of MIF reduced, and so did its downstream cytokines: TNF-α and IL-6. The inflammation reaction of the rats' corneas lightened after pretreated with 4-IPP. MIF may play a role in the innate immune response of the corneal resistance against A. fumigatus.

Macrophage migration inhibitory factor regulates proliferation of gastric cancer cells via the PI3K/Akt pathway

AIM:To investigate the effects of macrophage migration inhibitory factor (MIF) on proliferation of human gastric cancer MGC-803 cells and expression of cyclin D1 and p27Kip1 in them,and further determine whether the effects are related to the PI3K/Akt signal transduction pathway. METHODS:Gastric cancer MGC-803 cells were cultured and then treated with 50 μg/L recombinant human MIF (rhMIF) with and without a PI3K inhibitor,LY294002 (25 μmol/L). MTT assay was used to detect the prolifer-ation of MGC-803 cells. Cell cycle was detected by flow cytometry. Expression of cyclin D1 and p27Kip1 mRNA was by reverse transcription-polymerase chain reaction. Protein expression of phosphorylated Akt (p-Akt),Akt,cyclin D1 and p27Kip1 was examined by immunocyto-chemistry and Western blotting. RESULTS:rhMIF signifi cantly stimulated the prolifera-tion of MGC-803 cells and cell cycle progression from G1 phase to S phase in a concentration-and time-de-pendent manner. After the MGC-803 cells were treated with rhMIF for 24 h,the expression of cyclin D1 was signifi cantly up-regulated compared with the cells not treated with rhMIF at both mRNA and protein levels(0.97 ± 0.02 vs 0.74 ± 0.01,P = 0.002; 0.98 ± 0.05 vs 0.69 ± 0.04,P = 0.003). The p27Kip1 was down-regulated but only statistically significant at the protein level. rhMIF significantly increased the expression of p-Akt,which reached the peak at 30 min,but did not affect the expression of Akt. However,LY294002 inhibited all the effects of rhMIF.CONCLUSION:Macrophage MIF increases the proliferation of gastric cancer cells,induces the expression of cyclin D1 at the transcriptional level and inhibits the expression of p27Kip1 at the post-transcriptional level via the PI3K/Akt pathway.

D-dopachrome tautomerase from Japanese sea bass(Lateolabrax japonicus) is a chemokine-like cytokine and functional homolog of macrophage migration inhibitory factor

D-dopachrome tautomerase(DDT),a member of the macrophage migration inhibitory factor(MIF)protein superfamily,is a newly described cytokine with chemokine-like characteristics.However,research on fish DDT remains limited.In this study,we identified a DDT homolog(LjDDT)from the Japanese sea bass,Lateolabrax japonicus.Sequence analysis showed that LjDDT had typical sequence features of known DDT and MIF homologs and was most closely related to DDT of rock bream(Oplegnathus fasciatus).LjDDT transcripts were detected in all tested tissues of healthy Japanese sea bass,with the highest expression found in the liver.Upon infection with Vibrio harveyi,LjDDT transcripts were significantly down-regulated in the three tested tissues,including the liver,spleen,and head kidney.Recombinant LjDDT(rLjDDT)and the corresponding antibody(anti-rLjDDT)were subsequently prepared.The administration of 100μg/g anti-rLjDDT had a statistically significant protective effect on the survival of V.harveyi-infected fish.Moreover,rLjDDT was able to induce the migration of monocytes/macrophages(MO/MФ)and lymphocytes both in vitro and in vivo,but without significant influence on the migration of neutrophils.rLjDDT exhibited chemotactic activity for lipopolysaccharide(LPS)-stimulated M1-type MO/MΦin vitro,but not for cAMP-stimulated M2-type MO/MΦ.Furthermore,the knockdown of LjCD74,but not LjCXCR4,significantly down-regulated the rLjDDT-enhanced migration of MO/MΦand relieved the rLjMIF-inhibited migration of MO/MΦ.These results indicate that LjCD74 may be the major chemotactic receptor of LjDDT and LjMIF in Japanese sea bass MO/MΦ.Combined rLjDDT+rLjMIF treatment had no significant effect on the migration of MsiRNA,LjCD74si-,or LjCXCR4sitreated MO/MΦcompared to the control group,suggesting that the roles of LjDDT and LjMIF may be antagonistic.In conclusion,our study demonstrates for the first time that DDT may play a role in the immune responses of fish against bacterial infection through chemotactic recruitment of MO/MΦvia mediation of CD74 as an antagonist of MIF.

Association of the macrophage migration inhibitory factor promoter polymorphisms with benign lymphoepithelial lesion of lacrimal gland

AIM： To identify the association of the macrophage migration inhibitory factor （MIF） gene polymorphism with the susceptibility of benign lymphoepithelial lesions （BLEL） of the lacrimal gland. METHODS： A total of 40 BLEL of lacrimal gland cases were matched with 40 healthy subjects （HS）. Extraction the plasma and whole blood DNA of patients of lacrimal gland BLEL and HS. Elisa and polymerase chain reaction was used to determine in plasma contents of MIF and MIF gene SNP-173G〉C and STR -794 CATT（8） polymorphism, respectively. RESULTS： The MIF levels in plasma were significantly higher in patients with lacrimal gland BI.EL versus HS （P〈0.001）. The -173 G〉C MIF polymorphism was significantly associated with lacrimal gland BLEL, with a significantly higher frequency of the C allele in lacrimal gland BLEL patients compared with HS （OR=2.38, 95% C1=1.07-5.31, P=0.032）, and the -173 C/x is more frequent in patients than in HS, P=0.037. Besides, we found that the carriage rate of the MIF -173C/x is associated with higher plasma levels of MIF in the BLEI. of lacrimal gland. CONCLUSION： MIF -173G/C variants play an insidious role in susceptibility of BLEL of lacrimal gland. Otherwise,there is no statistically significant correlation exists between MIF-794 CATT （） and BLEL of lacrimal gland.

Macrophage migration inhibitory factor decreased T-type Ca^(2+) channel current through activating Src

Aims T-type Ca2+ current(ICaT)plays an important role in the pathogenesis of atrial fibrillation（AF）.The present study sought to investigate the role of Macrophage migration inhibitory factor（MIF）,a pleiotropic cytokine,in the regulation of T-type Ca2+ channel in atrium myocytes.Methods We used whole-cell voltage-clamp technique and biochemical assays to study the regulation and expression of ICa,T in mouse atrium myocytes（HL-1 cells）.Results Serum MIF concentrations was slightly increased in patients with AF compared to sinus rhythm（SR） controls.In cultured HL-1 cells, significant amounts of MIF were produced in response to hydrogen peroxide（H2O2）,but not AngiotensinⅡ（AngⅡ）. Mouse recombinant MIF（rMIF）（20 or 40 nM,24 h） suppressed peak ICa,T by-38%and-60%in a concentration-dependent manner,impaired the voltage-dependent activation of ICa,T,and down-regulated of TCC alG mRNA.Src inhibitors genistein and PPl significantly enhanced ICaT.The depression of ICa,T induced by rMIF could be reversed by genistein and PP1.Conclusions MIFis involved in the pathogenesis of AF,probably by decreasing ICa,T through impairment of the channel function and activation of c-Src kinases in atrium myocytes.

Effects of antisense oligonucleotides on theexpression of macrophage migration inhibitoryfactor on macrophages

To investigate the effects of antisense oligonucleotides on the expression of macrophage migration inhibitory factor (MIF) on macrophages, the mouse phosphorothioate oligonucleotides were designed and synthesized with the sequences of antisense, 5′-TACGGATACAAGTAGCAC-3′; Sense, 5′-ATGCCTATGTTCATCGTG-3′; Missense, 5′-CTCTCAGACTCGATCTGT-3′. These phosphorothioate oligonucleotides were then transfected into cultured macrophages ( RAW264.7 ) by luciferase vector, and the transfected macrophages were incubated with Lipopolysaccharide (LPS) (1?ng/ml) for various periods of times and collected afterwards. The content of MIF protein in the cultural supernatants was determined by ELISA, cellular RNA extracted and the expression of MIF mRNA was examined by RT-PCR analysis. The experimental results showed that LPS could induce a time-dependent specific expression of MIF on macrophages, in which the MIF mRNA in cells and the MIF protein in cultural supernatants appeared after 3 h and reached their highest concentration at 9-12?h after LPS stimulation. The levels of mRNA and proteins in the macrophages treated with antisense olignucleotides were decreased significantly after stimulation with LPS in comparison with that of stimulation with LPS alone or with that with LPS plus sense or missense oligonucleotides. There were no differences among those without LPS stimulation. It is concluded that macrophages stimulated with LPS express MIF, and the antisense olignucleotides of MIF inhibit the expression of MIF mRNA as well as the secretion of MIF proteins in macrophages.

Moxibustion of Zusanli(ST36)and Shenshu(BL23)alleviates the inflammation of rheumatoid arthritis in rats through regulating macrophage migration inhibitory factor/glucocorticoids signaling

OBJECTIVE:To test the hypothesis that moxibustion may inhibit rheumatoid arthritis(RA)synovial inflammation by regulating the expression of macrophage migration inhibitory factor(MIF)/glucocorticoids(GCs).METHODS:Fifty male Sprague-Dawley rats were randomly divided into five groups(n=10 each):blank Control(CON)group,RA Model(RA)group,Moxibustion(MOX)group,MIF inhibitor(S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester(ISO-1)group,and Moxibustion+MIF inhibitor ISO-1(MOX+ISO-1)group.Rats in the ISO-1 group and ISO-1+MOX group were intraperitoneally injected with the inhibitor ISO-1.The rats in the RA group,ISO-1 group,MOX group,and ISO-1+MOX group were injected with Freund's complete adjuvant(FCA)in the right hind footpad to establish an experimental RA rat model.In the MOX group and MOX+ISO-1 group,rats were treated with Moxa.The thickness of the footpads of the rats in each group was measured at three-time points before,after modeling and after moxibustion treatment.The contents of serum MIF,corticosterone(CORT),tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)were detected by enzyme-linked immunosorbent assay;and the contents of synovial MIF were detected by Western blot.Hematoxylin-eosin(HE)staining method was used to observe the pathological changes of synovial tissue under a section light microscope,and pathological scoring was performed according to the grading standard of the degree of synovial tissue disease.RESULTS:Moxibustion was found to reduce the level of MIF and alleviate inflammation in RA rats in this study.In addition,after inhibiting the expression of MIF,the level of CORT increased,and the level of TNF-α decreased.Treating RA rats with inhibited MIF by moxibustion,the level of CORT was almost unchanged,but the level of TNF-α further decreased.The correlation analysis data suggested that MIF was positively related to the expression of TNF-α and negatively correlated with the expression of CORT.CONCLUSION:Reducing MIF to increase CORT and decrease TNF-α by moxibustion treatment in RA.MIF may be a factor for moxibustion to regulate the expression of CORT,but the expression of TNF-α is due to the incomplete regulation of the MIF.This study added to the body of evidence pointing to moxibustion's antiinflammatory mechanism in the treatment of RA.

甲状腺乳头状癌患者术后血清MMIF和IL-6表达水平与甲状旁腺功能减退持续时间的相关性研究

目的探究甲状腺乳头状癌患者术后血清巨噬细胞移动抑制因子(macrophage movement inhibitory factor,MMIF)和白细胞介素(interleukin,IL)-6表达水平与甲状旁腺功能减退持续时间的关系。方法选取北京市平谷区医院2020年5月~2022年2月133例甲状腺乳头状癌术后甲状旁腺功能减退患者,根据甲状旁腺功能减退持续时间的中位数将其分为长时组(>8周,n=65)和短时组(≤8周,n=68)。酶联免疫吸附法检测血清MMIF和IL-6水平,并分析二者与甲状旁腺功能减退持续时间的关系。结果长时组和短时组的年龄、女性占比、体质量指数、肿瘤直径、双侧中央区淋巴结清扫占比、术后引流量、包膜侵犯占比、甲状旁腺意外切除占比、术前血钙和甲状旁腺激素、术后第1天的肿瘤坏死因子-α水平,差异均无统计学意义(t/χ^(2)/Z=0.123~1.401,均P>0.05)。与短时组相比,长时组的手术时间[114(102,139)min vs 101(95,114)min]、术后第1天的MMIF(2.38±0.26 ng/ml vs 2.09±0.19ng/ml)和IL-6水平[14.10(12.47,15.13)ng/L vs 12.42(11.61,13.38)ng/L]均升高,差异具有统计学意义(Z/t=3.419~7.185,均P<0.05)。Pearson分析结果显示log10(甲状旁腺功能减退持续时间)与MMIF呈正相关关系(r=0.397,P=0.000)。Spearman分析结果显示甲状旁腺功能减退持续时间与手术时间和IL-6均呈正相关关系(rs=0.363,P=0.000;rs=0.281,P=0.001)。线性回归分析结果显示手术时间(t=2.734,P=0.007)、MMIF(t=4.265,P=0.000)和IL-6(t=3.006,P=0.003)均与甲状旁腺功能减退持续时间独立相关。结论MMIF和IL-6与甲状旁腺功能减退持续时间呈正相关关系,二者水平高提示患者甲状旁腺功能减退持续时间长。

抑制lncRNA TUG1下调核苷酸结合寡聚结构域样受体蛋白1炎症小体在延缓阿尔茨海默病进展的作用

目的探讨敲低长链非编码RNA(lncRNA)牛磺酸上调基因1(TUG1)抑制核苷酸结合寡聚结构域样受体蛋白1(NLRP1)炎症小体在缓解阿尔茨海默病进展中的作用。方法选取9~10周龄遗传背景为C57/BL6的野生型小鼠(WT组,10只)或淀粉样前体蛋白(APP)/早老素1(PS1)转基因小鼠(30只)。APP/PS1转基因小鼠随机分为模型(model)组,模型+敲低lncRNA TUG1组[model+lncRNA TUG1短发夹RNA(shRNA)组]和model+shRNA非靶标(NT)组,每组10只。分别采集12周龄第1天(3月龄)和32周龄第1天(8月龄)小鼠外周血和脑皮质组织,并分离皮质中的原代小胶质细胞和原代星形胶质细胞,每个时间点每组5只小鼠。Real-time PCR分别测定3月龄和8月龄上述4个分组小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和巨噬细胞移动抑制因子(MIF)mRNA的水平,以及原代星形胶质细胞中补体蛋白C1r和C1s mRNA的水平。ELISA法测定其外周血浆中MIF含量。对3月龄和8月龄小鼠脑皮质原代小胶质细胞和原代星形胶质细胞共培养。CCK-8法测定上述2种细胞的增殖能力。Western blotting分别测定3月龄和8月龄上述4个分组小鼠脑皮质组织中MIF、白细胞介素1β前体(pro-IL-1β)、凋亡相关斑点样蛋白(ASC)、Caspase-1(p20)、Caspase-1(full)、NLRP1及NLRP3蛋白的表达水平。采用免疫荧光染色法测定8月龄各分组小鼠脑皮质组织中β淀粉样蛋白(Aβ)表达。结果3月龄和8月龄时,与WT组小鼠相比,model组小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和MIF相对表达水平显著上调,原代小胶质细胞和原代星形胶质细胞增殖能力增强(P<0.05)。与model组相比,model+lncRNA TUG1 shRNA组小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和MIF的相对表达水平显著降低,原代小胶质细胞和原代星形胶质细胞增殖能力降低(P<0.05)。与WT组相比,model组小鼠外周血浆中MIF含量显著升高;小鼠脑皮质组织中pro-IL-1β、ASC、Caspase-1(p20)、Caspase-1(full)、NLRP1以及NLRP3的蛋白表达水平显著升高;Aβ免疫荧光强度明显增强(P<0.05)。与model组相比,model+lncRNA TUG1 shRNA组小鼠外周血浆中MIF含量显著降低;小鼠脑皮质组织中pro-IL-1β、ASC、Caspase-1(p20)、Caspase-1(full)和NLRP1的蛋白表达水平显著降低,Aβ免疫荧光强度明显降低(P<0.05),而NLRP3蛋白质的表达水平无明显变化(P>0.05)。与model组相比,model+shRNA NT组小鼠上述所有检测指标差异均无显著性(P>0.05)。结论APP/PS1转基因小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和MIF因子表达上调与脑皮质内NLRP1炎症小体激活成正相关,敲低lncRNA TUG1可缓解阿尔茨海默病的进展。

巨噬细胞迁移抑制因子对人胚胎干细胞存活、增殖和分化的影响

背景:巨噬细胞迁移抑制因子(macrophage migration inhibitory factor,MIF)是一种具有多效性作用的细胞因子,可以在不同类型干细胞中自分泌并且能调控细胞的增殖、分化和迁移。课题组前期研究证实人胚胎干细胞自分泌MIF,且在培养液中浓度基本固定。然而,MIF是否参与了人胚胎干细胞的存活、增殖和分化尚不清楚。目的:探究MIF对人胚胎干细胞存活、增殖和分化的作用。方法:(1)培养人胚胎干细胞H9,CCK-8法检测并绘制细胞生长曲线,采用酶联免疫吸附法定量检测培养基中MIF水平。(2)为了明确外源性MIF对人胚胎干细胞存活、增殖的影响,分为:对照组,细胞在干细胞培养基中正常培养;外源性MIF组,在干细胞培养基中分别添加30,100,300 ng/m L的MIF;MIF抑制剂ISO-1组,在干细胞培养基中分别添加2,7,21μmol/L的ISO-1;MIF+ISO-1组,在不同浓度ISO-1组中分别添加100 ng/m L MIF,采用CCK-8法检测上述各组细胞活力。(3)为进一步阐明MIF基因对人胚胎干细胞存活、增殖的影响,采用CRISPRCas9技术构建MIF敲除的H9细胞系,观察建系情况。(4)为了明确高浓度MIF对人胚胎干细胞初步分化是否有影响,在培养基中分别添加100 ng/m L MIF和100 ng/m L CXCR4中和抗体,采用实时荧光定量聚合酶链式反应(RT-q PCR)、免疫细胞荧光、蛋白质印迹法(Western blot)检测干细胞自我更新因子(KLF4、c-MYC、NANOG、OCT4、SOX2)及分化转录因子(FOXA2、OTX2)的表达水平。结果与结论:(1)人胚胎干细胞H9的对数生长期为3-6 d,正常生长的情况下自分泌MIF水平约为20 ng/m L,与细胞量无关;(2)与对照组相比,添加不同质量浓度MIF对人胚胎干细胞的增殖无影响(P>0.05);ISO-1明显抑制人胚胎干细胞的增殖,ISO-1浓度越大,抑制越明显(P<0.05);ISO-1中添加MIF可以减少ISO-1的抑制作用(P<0.05);(3)RT-q PCR检测MIF基因敲除约50%后,人胚胎干细胞生长活力显著降低并且无法建系成功;(4)在培养基中添加100 ng/m L外源性MIF,自我更新转录因子KLF4的m RNA、蛋白及荧光表达水平均下降;分化因子FOXA2的m RNA、蛋白及荧光表达水平均上升;(5)在培养基中添加100 ng/m L CXCR4中和抗体,KLF4的m RNA及蛋白表达水平均上升;FOXA2的m RNA及蛋白表达水平均下降,与MIF组表达趋势相反。综上所述,人胚胎干细胞自分泌的MIF是其存活所必需的;培养基中额外添加MIF并不能促进人胚胎干细胞增殖,但可以使自我更新因子KLF4表达下降,转录因子FOXA2表达上升,为下一步探明MIF对人胚胎干细胞分化的影响及机制提供了线索,MIF-CXCR4轴在其中起到一定的调控作用。

巨噬细胞移动抑制因子抑制剂对蛛网膜下腔出血大鼠脑损伤的保护作用

目的探讨巨噬细胞移动抑制因子(MIF)抑制剂对蛛网膜下腔出血(SAH)大鼠脑损伤的保护作用。方法将120只12月龄健康雄性大鼠按照随机数字表法分为假手术组、SAH组、小剂量、中剂量和大剂量抑制剂组,每组24只。采用枕大池二次注血法制作大鼠SAH动物模型,小剂量、中剂量和大剂量抑制剂组分别给予10 mg/kg、20 mg/kg和40 mg/kg剂量MIF抑制剂注射大鼠腹腔,测定五组大鼠炎症因子、神经细胞凋亡、脑含水量、血脑屏障通透性和神经功能情况。结果大鼠脑组织白介素-1β、肿瘤坏死因子-α及白介素-6蛋白表达、神经细胞凋亡指数、脑水肿指数、伊文氏蓝含量及神经行为学评分五组间比较,差异均有统计学意义(F=76.406、62.664、64.106、40.211、24.869、60.229、43.664,均P<0.01),与假手术组比较,SAH组白介素-1β、肿瘤坏死因子-α及白介素-6蛋白表达、神经细胞凋亡指数、脑水肿指数和伊文氏蓝含量增高,神经行为学评分下降,差异均有统计学意义(P<0.01),MIF抑制剂腹腔注射可逆转上述作用,且呈剂量-疗效依赖关系(P<0.05)。结论MIF抑制剂对SAH大鼠脑损伤具有明显的保护作用,且呈量效关系。

脓毒症合并急性肺损伤患者血清巨噬细胞移动抑制因子的变化及对预后的影响

目的 研究脓毒症合并急性肺损伤(ALI)患者血清巨噬细胞移动抑制因子(MIF)的变化及对预后的影响。方法 选择2021年5月至2023年12月河北北方学院附属第一医院收治的180例脓毒症患者,根据是否发生ALI分为ALI组(n=82)和非ALI组(n=98)。比较两组患者血清MIF及各项临床资料差异,分析脓毒症合并ALI的影响因素以及各影响因素对脓毒症合并ALI的诊断价值,比较不同血清MIF水平的脓毒症合并ALI患者生存预后差异。结果 ALI组的急性生理学与慢性健康状况评价Ⅱ(APACHEⅡ)评分、序贯器官衰竭评估(SOFA)评分、D-二聚体、血尿素氮及血清MIF均高于非ALI组(P<0.05)。多因素Logistic回归分析显示,APACHEⅡ评分和血清MIF是脓毒症合并ALI的影响因素(P<0.05)。受试者工作特征(ROC)曲线分析显示,单独血清MIF及与APACHEⅡ评分联合均对脓毒症合并ALI具有诊断效能,联合诊断的敏感度和特异度分别为90.24%和88.78%;Kaplan-Meier生存曲线分析显示,血清MIF升高与脓毒症合并ALI患者生存率降低相关(P<0.05)。结论 血清MIF水平升高与脓毒症合并ALI的发生及生存预后不良相关,血清MIF联合APACHEⅡ评分对脓毒症合并ALI具有一定诊断价值。

巨噬细胞移动抑制因子在急性肝衰竭小鼠肝脏炎症中的作用研究

目的探讨巨噬细胞移动抑制因子(macrophage migration inhibitory factor,MIF)在急性肝衰竭(acute liver failure,ALF)小鼠肝脏炎症中的作用。方法将18只雄性小鼠随机分为正常组、模型组、MIF拮抗剂ISO-1组。采用D-氨基半乳糖联合脂多糖诱导小鼠ALF模型,检测3组小鼠血清谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate aminotransferase,AST)和总胆红素(total bilirubin,TBIL)水平,HE染色观察肝脏病理形态学改变,Tunel染色观察肝细胞凋亡情况。采用酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测小鼠肝脏组织中的MIF、CXC趋化因子受体2(CXC chemokine receptor 2,CXCR2)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)的水平,免疫荧光观察MIF的表达。结果模型组小鼠较正常组小鼠肝组织结构破坏程度明显增加,肝细胞凋亡增多,肝功能受损;ISO-1能够减轻肝组织损害,减少肝细胞凋亡。模型组小鼠肝组织中MIF、CXCR2、TNF-α表达水平明显升高,而ISO-1能够显著降低MIF、CXCR2、TNF-α的表达水平,差异均有统计学意义(P<0.05)。结论MIF在ALF中的表达显著升高,抑制MIF可以改善肝组织损伤及炎性细胞因子表达,表明MIF在ALF中起重要作用。