Androgen signaling inhibits de novo lipogenesis to alleviate lipid deposition in zebrafish

Testosterone is closely associated with lipid metabolism and known to affect body fat composition and muscle mass in males.However,the mechanisms by which testosterone acts on lipid metabolism are not yet fully understood,especially in teleosts.In this study,cyp17a1-/-zebrafish(Danio rerio)exhibited excessive visceral adipose tissue(VAT),lipid content,and up-regulated expression and activity of hepatic de novo lipogenesis(DNL)enzymes.The assay for transposase accessible chromatinwithsequencing(ATAC-seq)results demonstrated that chromatin accessibility of DNL genes was increased in cyp17a1-/-fish compared to cyp17a1+/+male fish,including stearoyl-CoA desaturase(scd)and fatty acid synthase(fasn).Androgen response element(ARE)motifs in the androgen signaling pathway were significantly enriched in cyp17a1+/+male fish but not in cyp17a1-/-fish.Both androgen receptor(ar)-/-and wildtype(WT)zebrafish administered with Ar antagonist flutamide displayed excessive visceral adipose tissue,lipid content,and up-regulated expression and activity of hepatic de novo lipogenesis enzymes.The Ar agonist BMS-564929 reduced the content of VAT and lipid content,and down-regulated acetyl-CoA carboxylase a(acaca),fasn,and scd expression.Mechanistically,the rescue effect of testosterone on cyp17a1-/-fish in terms of phenotypes was abolished when ar was additionally depleted.Collectively,these findings reveal that testosterone inhibits lipid deposition by down-regulating DNL genes via Ar in zebrafish,thus expanding our understanding of the relationship between testosterone and lipid metabolism in teleosts.

A unique role of the pyrimidine de novo synthesis enzyme ODCase in Lysobacter enzymogenes

Bacterial species of the genus Lysobacter are environmentally ubiquitous with strong antifungal biocontrol potential.Heat-stable antifungal factor(HSAF)secreted by the biocontrol bacterium Lysobacter enzymogenes OH11 has broad-spectrum and highly efficient antifungal activity.Studying the biosynthetic regulations of HSAF would lay an important foundation for strain engineering toward improved HSAF production.In this work,we demonstrate that Le0752,an orotidine-5´-phosphate decarboxylase enzyme(ODCase)catalyzing a pivotal step of the UMP de novo biosynthesis pathway,is vital for HSAF-mediated antimicrobial activities and growth of L.enzymogenes OH11,but not for twitching motility.This gene regulates the production of HSAF by affecting the expression of lafB,a key gene in the HSAF biosynthesis operon,through the transcription factor Clp.Interestingly,bioinformatics analysis revealed that Le0752 belongs to the Group III ODCases,whereas its homologs in the closely related genera Xanthomonas and Stenotrophomonas belong to Group I,which contains most ODCases from Gram-positive bacteria,Gram-negative bacteria and cyanobacteria.Moreover,the Group I ODCase PXO_3614 from the Xanthomonas oryzae pv.oryzae PXO99A strain complemented the Le0752 mutant in regulating HSAF-mediated antagonistic activity.Together,these results highlight the important requirement of de novo pyrimidine biosynthetic enzymes for antibiotic HSAF production in L.enzymogenes,which lays an important foundation for improving HSAF production via metabolic flow design and for dissecting the regulatory functions of bacterial ODCases.

Treatment-induced neuroendocrine prostate cancer and de novo neuroendocrine prostate cancer:Identification,prognosis and survival,genetic and epigenetic factors

Neuroendocrine prostate cancer(NEPC)shows an aggressive behavior compared to prostate cancer(PCa),also known as prostate adenocarcinoma.Scanty foci in PCa can harbor genetic alternation that can arise in a heterogeneity of prostate cancer.NEPC may arise de novo or develop following androgen deprivation therapy(ADT).NEPC that arise following ADT has the nomenclature“treatmentemerging/induced NEPC(t-NEPC)”.t-NEPC would be anticipated in castration resistant prostate cancer(CRPC)and metastatic PCa.t-NEPC is characterized by low or absent androgen receptor(AR)expression,independence of AR signaling,and gain of neuroendocrine phenotype.t-NEPC is an aggressive metastatic tumor,develops from PCa in response to drug induced ADT,and shows very short response to conventional therapy.t-NEPC occurs in 10%-17%of patients with CRPC.De novo NEPC is rare and is accounting for less than 2%of all PCa.The molecular mechanisms underlying the trans-differentiation from CRPC to t-NEPC are not fully elucidated.Sphingosine kinase 1 plays a significant role in t-NEPC development.Although neuroendocrine markers:Synaptophysin,chromogranin A,and insulinoma associated protein 1(INSM1)are expressed in t-NEPC,they are non-specific for diagnosis,prognosis,and follow-up of therapy.t-NEPC shows enriched genomic alteration in tumor protein P53(TP53)and retinoblastoma 1(RB1).There are evidences suggest that t-NEPC might develop through epigenetic evolution.There are genomic,epigenetic,and transcriptional alterations that are reported to be involved in development of t-NEPC.Knock-outs of TP53 and RB1 were found to contribute in development of t-NEPC.PCa is resistant to immunotherapy,and at present there are running trials to approach immunotherapy for PCa,CRPC,and t-NEPC.

Metabolic complications of psychotropic medications in psychiatric disorders:Emerging role of de novo lipogenesis and therapeutic consideration

Although significant advances have been made in understanding the pathophysiology of psychiatric disorders(PDs),therapeutic advances have not been very convincing.While psychotropic medications can reduce classical symptoms in patients with PDs,their long-term use has been reported to induce or exaggerate various pre-existing metabolic abnormalities including diabetes,obesity and non-alcoholic fatty liver disease(NAFLD).The mechanism(s)underlying these metabolic abnormalities is not clear;however,lipid/fatty acid accumulation due to enhanced de novo lipogenesis(DNL)has been shown to reduce membrane fluidity,increase oxidative stress and inflammation leading to the development of the aforementioned metabolic abnormalities.Intriguingly,emerging evidence suggest that DNL dysregulation and fatty acid accumulation could be the major mechanisms associated with the development of obesity,diabetes and NAFLD after long-term treatment with psychotropic medications in patients with PDs.In support of this,several adjunctive drugs comprising of anti-oxidants and antiinflammatory agents,that are used in treating PDs in combination with psychotropic medications,have been shown to reduce insulin resistance and development of NAFLD.In conclusion,the above evidence suggests that DNL could be a potential pathological factor associated with various metabolic abnormalities,and a new avenue for translational research and therapeutic drug designing in PDs.

Endoscopic and pathological characteristics of de novo colorectal cancer:Retrospective cohort study

BACKGROUND Endoscopy has rapidly developed in recent years and has enabled further investigation into the origin and features of intestinal tumors.The small size and concealed position of these tumors make it difficult to distinguish them from nonneoplastic polyps and carcinoma in adenoma(CIA).The invasive depth and metastatic potential determine the operation regimen,which in turn affects the overall survival and distant prognosis.The previous studies have confirmed the malignant features and clinicopathological features of de novo colorectal cancer(CRC).AIM To provide assistance for diagnosis and treatment,but the lack of a summary of endoscopic features and assessment of risk factors that differ from the CIA prompted us to conduct this retrospective study.METHODS In total,167 patients with small-sized CRCs diagnosed by endoscopy were reviewed.The patients diagnosed as advanced CRCs and other malignant cancers or chronic diseases that could affect distant outcomes were excluded.After screening,63 cases were excluded,including 33 de novo and 30 CIA cases.Patient information,including their follow-up information,was obtained from an electronic His-system.The characteristics between two group and risk factors for invasion depth were analyzed with SPSS 25.0 software.RESULTS Nearly half of the de novo CRCs were smaller than 1 cm(n=16,48.5%)and the majority were located in the distal colon(n=26,78.8%).The IIc type was the most common macroscopic type of de novo CRC.In a Pearson analysis,the differential degree,Sano,JNET,and Kudo types,surrounding mucosa,and chicken skin mucosa(CSM)were correlated with the invasion depth(P<0.001).CSM was a significant risk factor for deep invasion and disturbed judgment of endoscopic ultrasound.A high degree of tumor budding and tumor-infiltrating lymphocytes are accompanied by malignancy.Finally,de novo CRCs have worse outcomes than CIA CRCs.CONCLUSION This is the first comprehensive study to analyze the features of de novo CRCs to distinguish them from nonneoplastic polyps.It is also the first study paying attention to CSM invasive depth measurement.This study emphasizes the high metastatic potential of de novo CRCs and highlights the need for more research on this tumor type.

De novo transcriptome assembly of Aureobasidium melanogenum CGMCC18996 to analyze theβ-poly(L-malic acid)biosynthesis pathway under the CaCO_(3) addition

β-Poly(L-malic acid)(PMLA)is a water-soluble biopolymer used in food,medicine and other industries.To date,the biosynthesis pathway of PMLA has not been fully elucidated.In this study,we sequenced the transcriptom e of strain Aureobasidium melanogenum under 20 g/L CaCO_(3) addition.The resulting sequencing reads were assembled and annotated for the differentially expressed genes(DEGs)analysis and novel transcripts identification.The result indicated that with the CaCO_(3) addition,the tricarboxylic cycle(TCA)cycle and glyoxylate pathway were up-regulated,and it also found that a non-ribosomal peptide synthetase(NRPS)like protein was highly expressed.The DEGs analysis showed a high expression level of malate dehydrogenase(MDHC)and phosphoenolpyruvate carboxykinase(PCKA)in the CaCO_(3) group,which indicated a cytosolic malate activity.We speculated that the malate should be transported to or synthesized in the cytoplasm,which was then polymerized to PMLA by the NRPS-like protein,accompanied by the up-regulated TCA cycle providing ATP for the polymerization.Depending on the analysis,we assumed that an NRPS-like protein,the TCA cycle,and the cytosolic malate together are contributing to the PMLA biosynthesis.

Drug-coated balloons for treating de novo lesions in large coronary vessels:A case report

BACKGROUND Percutaneous transluminal coronary angioplasty,while an effective intervention,can frequently lead to acute occlusion with severe consequences.Although clinical trials have demonstrated the efficacy of drug-coated balloons(DCB)in treating acute coronary artery occlusion and in preventing restenosis,there has been limited exploration on the use of DCB in treating de novo lesions in large vessels.Currently,DCB are only recommended for patients with small vessel lesions and in-stent restenosis lesions,those at high risk of bleeding,and other special groups of patients.CASE SUMMARY This report presents a case of successful drug-coated balloon treatment of de novo lesions in large coronary vessels.Postoperatively,the patient demonstrated favorable recovery,with subsequent examination results revealing no significant differences from the previous examination.CONCLUSION The successful treatment of the patient in our case highlights the potential of DCB in the treatment of de novo lesions in large coronary vessels.

Incidence, risk factors and outcome of de novo tumors in liver transplant recipients focusing on alcoholic cirrhosis

Orthotopic liver transplantation(OLT) is an established life-saving procedure for alcoholic cirrhotic(AC) patients, but the incidence of de novo tumors ranges between 2.6% and 15.7% and is significantly increased in comparison with patients who undergo OLT for other etiologies. Tobacco, a known carcinogen, has been reported to be between 52% and 83.3% in AC patients before OLT. Other risk factors that contribute to the development of malignancies are dose-dependent immunosuppression, advanced age, viral infections, sun exposure, and premalignant lesions(inflammatory bowel disease, Barrett's esophagus). A significantly more frequent incidence of upper aerodigestive(UAD) tract, lung, skin, and kidney-bladder tumors has been found in OLT recipients for AC in comparison with other etiologies. Liver transplant recipients who develop de novo non-skin tumors have a decreased long-term survival rate compared with controls. This significantly lower survival rate is more evident in AC recipients who develop UAD tract or lung tumors after OLT mainly because the diagnosis is usually performed at an advanced stage. All transplant candidates, especially AC patients, should be encouraged to cease smoking and alcohol consumption in the pre- and postOLT periods, use skin protection, avoid sun exposure and over-immunosuppression, and have a yearly otopharyngolaryngeal exploration and chest computed tomography scan in order to prevent or reduce the incidence of de novo malignancies. Although still under investigation, substitution of calcineurin inhibitors for sirolimus or everolimus may reduce the incidence of de novo tumors after OLT.

中华蜜蜂幼虫肠道参考转录组的de novo组装及SSR分子标记鉴定

【目的】利用RNA seq技术对中华蜜蜂(Apis cerana cerana,简称中蜂)幼虫肠道参考转录组进行de novo组装,并进行功能及代谢通路注释,进而利用该转录组数据进行中蜂幼虫的SSR分子标记鉴定。【方法】实验室条件下饲养中蜂幼虫,将纯化的蜜蜂球囊菌(Ascosphaera apis,简称球囊菌)孢子饲喂3日龄幼虫,剖取4、5和6日龄幼虫肠道,液氮速冻。将健康幼虫肠道与感染球囊菌的幼虫肠道同时进行Illumina测序。通过对raw reads的过滤得到clean reads,利用Trinity软件组装得到unigenes。通过BLASTx(E-value<10-5)比对NCBI Nr、Swiss-Prot、KOG和KEGG数据库,对unigenes进行功能和代谢通路注释。利用MISA软件对所有unigenes进行SSR搜索,并利用Primer Premier 5软件设计特异性SSR引物,通过常规PCR对来源于北京、辽宁兴城和四川成都的中蜂幼虫肠道样本进行SSR位点鉴定。【结果】中蜂幼虫肠道的RNA seq共得到35 670 000条reads,de novo组装得到43 557个unigenes,平均长度为898 nt。共有18 225个unigenes可被注释到上述公共蛋白数据库,单独注释到NCBI Nr、Swiss-Prot、KOG和KEGG数据库的unigenes数分别为3 899、443、37和10个。KOG注释结果显示,11 442条unigenes分布于25个基因家族,其中注释到RNA加工和修饰家族的基因数最多,达1 249个。9 679个unigenes的GO分类结果显示,在生物学进程分类中,注释到细胞进程的基因最多,达4 201个,在分子功能和细胞组分类中,注释到结合与细胞的基因数最多,分别为4 935和2 900个。4 517个unigenes可注释到KEGG数据库中的216个代谢通路,注释到核糖体的基因数最多,达385个。利用MISA软件,可在7 763个unigenes搜索到13 448个SSR位点,随机选取20对SSR引物对国内3个不同来源的中蜂幼虫肠道样本的SSR位点进行扩增,有6对引物可鉴定出SSR分子标记。【结论】成功组装并注释了中蜂幼虫肠道参考转录组,可为中蜂及其幼虫的分子生物学及组学研究提供重要的参考信息,也可用于补充、丰富和检验东方蜜蜂的参考基因组,基于此转录组数据开发出6个中蜂的SSR分子标记,可应用于中蜂的基因图谱构建、基因多样性分析、基因定位等研究,也说明利用转录组数据开发非模式生物SSRs的方法可行。

Experimental and modeling study of de novo formation of PCDD/PCDF on MSW fly ash

The effect of sulfur dioxide （SO2） on the formation of polychlorinated dibenzo-p-dioxins （PCDDs） and polychlorinated dibenzofurans （PCDFs） has been studied in an entrained-flow reactor （EFR） under simulated waste combustion conditions. A chlorination model based on conditional probability was employed to evaluate the homologue patterns of PCDDs and PCDFs. Results revealed that the presence of SO2 did not alter the formation pathway although SO2 suppressed PCDD/F formation. The prediction model of PCDF showed good agreement with the experimental data （R--0.95）, whereas the prediction for PCDDs did not correlate well with the experimental data. This may be explained because potential chlorination pathways play a significant role in PCDF formation, whereas PCDDs are mainly formed through condensation reactions. Furthermore, the result indicated that the steric hindrance during formation has more effects on PCDD than on PCDF due to the symmetric molecular structures of PCDDs.

基于混合策略的de novo序列拼接算法构造

在对3种de novo(从头)序列拼接的基本策略进行分析的基础上,该文研究了混合策略序列拼接算法的构造过程,从而整合多个单一策略优点;再利用形式化方法和形式化平台方面的优势,结合领域分析建模和产生式编程的方法,构造了2个基于OLC策略的算法(OLC_assembly_1,OLC_assembly_2)及1个基于DBG策略的算法(DBG_assembly),进一步组装出在(OLC+DBG)→OLC混合模式下的算法(简称ODO算法);最后,从GenBank中选取了3个实验样本,从N50、Contigs number、Coverage等角度,比较了在3个单一策略下的算法和ODO构造算法的拼接结果,分析了coverage depth和k值的变化对拼接结果的影响.实验结果表明:该文实现的ODO算法比单一策略在序列拼接时所产生的结果在N50和Coverage等参数上均有一定的优势.

A de novo originated gene depresses budding yeast mating pathway and is repressed by the protein encoded by its antisense strand

Recent transcription profiling studies have revealed an unexpectedly large proportion of antisense transcripts in eukaryotic genomes. These antisense genes seem to regulate gene expression by interacting with sense genes. Previ- ous studies have focused on the non-coding antisense genes, but the possible regulatory role of the antisense protein is poorly understood. In this study, we found that a protein encoded by the antisense gene ADF1 acts as a transcription suppressor, regulating the expression of sense gene MDF1 in Saccharomyces cerevisiae. Based on the evolutionary, ge- netic, cytological and biochemical evidence, we show that the protein-coding sense gene MDF1 most likely originated de novo from a previously non-coding sequence and can significantly suppress the mating efficiency of baker＇s yeast in rich medium by binding MATa2 and thus promote vegetative growth. These results shed new light on several im- portant issues, including a new sense-antisense interaction mechanism, the de novo origination of a functional gene, and the regulation of yeast mating pathway.

De novo autoimmune hepatitis in liver transplant: State-of-the-art review

In the two past decades, a number of communications, case-control studies, and retrospective reports have appeared in the literature with concerns about the development of a complex set of clinical, laboratory and histological characteristics of a liver graft dysfunction that is compatible with autoimmune hepatitis. The de novo prefix was added to distinguish this entity from a pre-transplant primary autoimmune hepatitis, but the globally accepted criteria for the diagnosis of autoimmune hepatitis have been adopted in the diagnostic algorithm. Indeed, de novo autoimmune hepatitis is characterized by the typical liver necroinflammation that is rich in plasma cells, the presence of interface hepatitis and the consequent laboratory findings of elevations in liver enzymes, increases in serum gamma globulin and the appearance of nonorgan specific auto-antibodies. Still, the overall features of de novo autoimmune hepatitis appear not to be attributable to a univocal patho-physiological pathway because they can develop in the patients who have undergone liver transplantation due to different etiologies. Specifically, in subjects with hepatitis C virus recurrence, an interferon-containing antiviral treatment has been indicated as a potential inception of immune system derangement. Herein, we attempt to review the currently available knowledge about de novo liver autoimmunity and its clinical management.

基于不确定De Novo规划的流域初始水权配置模型

利用区间数来描述流域初始水权配置系统的不确定参数,在系统总的资源约束限定的条件下,从最优系统设计的角度建立了决策信息不确定条件下的流域初始水权De Novo规划模型,引入系统结构方程对初始用水权和初始排污权的分配方案进行优化,实现流域初始水权配置系统的整体最优设计。最后,通过算例分析验证了该模型的有效性。

Donor transmitted and de novo cancer after liver transplantation

Cancers in solid organ recipients may be classified as donor transmitted,donor derived,de novo or recurrent.The risk of donor-transmitted cancer is very low and can be reduced by careful screening of the donor but cannot be abolished and,in the United Kingdom series is less than 0.03%.For donors with a known history of cancer,the risks will depend on the nature of the cancer,the interventions given and the interval between diagnosis and organ donation.The risks of cancer transmission must be balanced against the risks of death awaiting a new graft and strict adherence to current guidelines may result increased patient death.Organs from selected patients,even with high-grade central nervous system(CNS)malignancy and after a shunt,can,in some circumstances,be considered.Of potential donors with non-CNS cancers,whether organs may be safely used again depends on the nature of the cancer,the treatment and interval.Data are scarce about the most appropriate treatment when donor transmitted cancer is diagnosed:sometimes substitution of agents and reduction of the immunosuppressive load may be adequate and the impact of graft removal should be considered but not always indicated.Liver al-lograft recipients are at increased risk of some de novo cancers,especially those grafted for alcohol-related liver disease and hepatitis C virus infection.The risk of lymphoproliferative disease and cancers of the skin,upper airway and bowel are increased but not breast.Recipients should be advised to avoid risk behavior and monitored appropriately.

Risk factors for de novo hepatitis B infection in pediatric living donor liver transplantation

AIM: To investigate the incidence of de novo hepatitis B virus (HBV) infection after pediatric living donor liver transplantation (LDLT) and to analyze the risk factors associated with this de novo HBV infection.

面向下一代测序技术的de novo序列拼接工具综述

序列拼接是生物信息学的基础问题.全面总结了面向下一代测序技术的de novo DNA序列拼接工具,介绍下一代测序平台产生的数据特点以及de novo序列拼接算法所面临的挑战;给出序列拼接算法的形式化定义,总结目前最常用的拼接策略以及根据相应策略开发的拼接工具的特点和实现细节;对评估拼接性能的主要参数进行描述,并通过不同物种、不同规模的真实基因组序列数据对多个具有代表性的拼接工具进行测试,比较它们的拼接性能以验证相应的工具特点.为研究人员提供工具选择指导或改善拼接工具性能提供帮助;最后总结并阐述序列拼接工具存在的问题和发展趋势.

De novo combination therapy with lamivudine and adefovir dipivoxil in chronic hepatitis B patients

AIM:To investigate the appropriate time for combination therapy in HBeAg positive chronic hepatitis B(CHB) patients with decompensated cirrhosis.METHODS:Thirty HBeAg positive CHB patients with decompensated cirrhosis were enrolled in the study.All of the patients were given 48 wk combination therapy with lamivudine(LAM) and adefovir dipivoxil(ADV) .Briefly,10 patients were given the de novo combination therapy with LAM and ADV,whereas the other 20 patients received ADV in addition to LAM after hepatitis B virus(HBV) genetic mutation.RESULTS:Serum alanine aminotransferase and total bilirubin were both improved in the two groups at 4,12,24 and 48 wk after treatment.Serum albumin was also improved at 24 and 48 wk after combination therapy in both groups.The serum HBV DNA level wasstill detectable in every patient in the two groups at 4 and 12 wk after combination treatment.However,in the de novo combination group,serum HBV DNA levels in 4(40%) and 9(90%) patients was decreased to below 1×10 3 copies/mL at 24 and 48 wk after the combination treatment,respectively.In parallel,serum HBV DNA levels in 2(20%) and 8(40%) patients in the add-on combination group became undetectable at 24 and 48 wk after combination treatment,respectively.Furthermore,6(60%) patients in the de novo combination group achieved HBeAg seroconversion after 48 wk treatment,whereas only 4(20%) patients in the add-on combination group achieved seroconversion.Child-Pugh score of patients in the de novo combination group was better than that of patients in the add-on combination group after 48 wk treatment.Moreover,patients in the de novo combination group had a significantly decreased serum creatinine level and elevated red blood cell counts.CONCLUSION:De novo combination therapy with LAM and ADV was better than add-on combination therapy in terms of Child-Pugh score,virus inhibition and renal function.

Prevention of de novo HBV infection by the presence of anti-HBs in transplanted patients receiving core antibody-positive livers

AIM： To analyze whether the presence of anti-HBs in liver transplant recipients is effective in preventing HBV infection. METHODS： Twenty-three patients receiving anti-HBc positive liver were studied. Nine recipients were anti-HBc positive as a result of previous HBV infection. Of them, one also received HBV vaccine during the pre-liver transplantation period. Fourteen recipients were anti-HBs positive due to HBV vaccine administered during the pretransplant period. Liver biopsy was obtained in 10/14 anti-HBc negative/anti-HBs positive recipients and in 4/9 anti-HBc positive recipients. RESULTS： After a mean foUow-up period of 46 months, 1 recipient with protective serum anti-HBs levels developed de novo HBV infection as a consequence of immune escape HBV mutants. Among the 14 vaccinated anti-HBc negative/anti-HBs positive recipients, 1/10 patients with available liver biopsy （10%） had liver HBV-DNA at 13 mo post-liver transplantation without serum viral markers and did not develop de novo HBV infection.The vaccinated anti-HBc positive recipient without HBV vaccine response was HBV-DNA positive in serum and liver, viral DNA was continuously negative in the following tests, so a spontaneous seroconversion was diagnosed. CONCLUSION： The presence of anti-HBs as a result of HBV vaccine or past HBV infection seems to be effective at protecting patients receiving livers from anti-HBc positive donors. However, the emergence of immune escape HBV mutants, which can evade the anti-HBs protection, should be considered as a risk of HBV infection.

Compound Kushen injection induces immediate hypersensitivity reaction through promoting the production of platelet-activating factor via de novo pathway

OBJECTIVE Compound Kushen injection(CKI)is a bis-herbal formulation extracted from Kushen(Radix Sophorae Flavescentis)and Baituling(Rhizoma Heterosmilacis Japonicae).Clinically,it is used as the adjuvant treatment of cancer.However,with the increased application,the cases of immediate hypersensitivity reactions(IHRs)also gradually rise.In this study,we investigated the underlying mechanism(s)and active constituent(s)for CKI-induced IHRs in experimental models.METHODS T helper 2(Th2)immunity-amplified mice were prepared by aluminum adjuvant.Anaphylactic shock was detected by measuring rectal thermometry in propranolol pretreated mice.For evaluating microvascular permeability,Evans blue extravasation assay was used.Platelet-activating factor(PAF),serum total IgE(tIgE)and mouse mast cell protease 1(MMCP1)were measured by ELISA.RESULTS The obtained results showed that CKI did not elevate serum tIgE and MMCP1 after consecutive immunization for five weeks,but could induce Evans blue extravasation(local)and cause obvious hypothermia(systemic)after a single injection.Further study showed that alkaloids in Kushen,especially matrine,were responsible for CKI-induced IHRs.Mechanism study showed that various PAF receptor antagonists could significantly counter CKI-induced IHRs locally or systemically.In cell system,CKI was able to promote PAF production in a non-cell-selective manner.In cell lysate,the effect of CKI on PAF production became stronger and could be abolished by blocking de novo pathway.CONCLUSION In conclusion,our study identifies,for the first time,that CKI is a PAF inducer.It causes non-immunologic IHRs,rather than IgE-dependent IHRs,by promoting PAF production through de novo pathway.Alkaloids in Kushen,especially matrine,are the prime culprits for IHRs.Our findings may provide a potential approach for preventing and treating CKI-induced IHRs.