Involvement of haptoglobin in disease development

Haptoglobin(HP)is a liver glycoprotein that is actively synthesized during in-flammatory and hemolytic processes.It also has pro-oxidant and proinflam-matory properties,which are a function of its genotype.The genetic polymorp-hism of the chains leads to synthesis of three phenotypes/proteins,which are related to the number and type of chains and their molecular weight,namely HP1-1,HP1-2 and HP2-2.Patients with HP2-2 have more vascular complications,while those with HP1-1 have fewer.HP is involved in the worsening of diseases,such as HP2-2 in aggravation of vaso-occlusive crises in sickle cell disease,and worsening of the pathophysiology of other diseases.In contrast,HP1-1 confers better protection against diseases.All of this suggests that further studies should be conducted,including experimental and analytical studies focused on de-monstrating the influence of different HP genotypes on individual clinical and hematological data.This would help in understanding the role played by this genetic polymorphism in the pathophysiology of diseases.

Multifaceted role of haptoglobin:Implications for disease development

Haptoglobin,a protein primarily recognized for its role in sequestering free hemoglobin,has been identified as a molecule with diverse and underexplored functions in the pathophysiology of various diseases.This editorial explores the multifaceted roles of haptoglobin,highlighting its involvement in inflammatory responses and immune regulation and its potential implications in chronic diseases such as diabetes,cardiovascular disorders,and cancer.Through a synthesis of recent research findings,this editorial reveals the importance of haptoglobin in disease mechanisms and underscores the need for further investigation to fully elucidate its therapeutic potential.A comprehensive understanding of haptoglobin’s novel functions may catalyze the development of innovative diagnostic and therapeutic modalities in clinical practice.

Influence of Haptoglobin and Hemoglobin Phenotypic Polymorphisms on Sickle Cell Disease Morbidity

Objectives: Sickle cell disease (SCD) has a varied clinical and biological expression depending on the hemoglobin phenotype: SSFA2, SFA2, SAFA2 and SC. Considering the antioxidant properties of the different haptoglobin phenotypes (Hp 1-1, Hp 2-1, Hp 2-2), it seemed relevant to know their influence on the morbidity of the different hemoglobin phenotype of SCD. Thus, the objective of this study was to identify associations between haptoglobin phenotype and morbidity of different SCD phenotypes. Methods: In a retrospective cross-sectional descriptive and analytical study, with a cohort of 170 black African carriers of hemoglobin S, in Ivory Coast, West Africa, hemoglobin and haptoglobin phenotypes were determined by electrophoretic methods. Results: The three major phenotypes of haptoglobin polymorphism were found in the SCD cohort: Hp 1-1 (24.1%), Hp 2-1 (56.5%), Hp 2-2 (19.4%). Vaso-occlusions were associated with haptoglobin phenotype Hp 1-1, (OR = 2.03;CI95% = [1.06 - 3.9];p Conclusions: Haptoglobin phenotype was associated to morbidity-adjusted hemoglobin phenotype. The study revealed a greater probability of a worse morbidity when the hemoglobin phenotype is homozygous. Unexpectedly, the worse morbidity is associated to Hp 1-1 haptoglobin phenotype, the most powerful antioxidant within the different haptoglobin phenotypes. Associations found were not systematic and need further studies to enlighten the determinism of SCD morbidity.

血清APN、visfatin和Haptoglobin与PCOS患者IR指数的关系及临床意义

目的研究血清脂联素(APN)、内脂素(visfatin)、结合珠蛋白(Hp)水平与多囊卵巢综合征(PCOS)患者胰岛素抵抗(IR)指数的临床意义。方法选择2018年2月至2021年3月南阳市中心医院诊治的102例PCOS患者,分为肥胖组(BMI≥23 kg/m^(2),47例)和非肥胖组非肥胖组(BMI<23 kg/m^(2),55例)、IR组(HOMA-IR≥2.69,52例)和非IR组(HOMA-IR<2.69,50例),另选择同期健康志愿者96例作为对照组。检测不同人群血清APN、visfatin、Hp水平,分析三者与IR指数关系及对IR的预测价值。结果FPG、黄体生成素(LH)、visfatin、Hp、HOMA-IR、空腹胰岛素(FINS)、LH/卵泡雌激素(FSH)和体质量指数(BMI)水平:肥胖组>非肥胖组>对照组,APN水平:肥胖组<非肥胖组<对照组,差异均有统计学意义(P<0.05)。血清APN水平与HOMA-IR呈负相关(P<0.05),visfatin、Hp水平与HOMA-IR呈正相关(P<0.05)。IR组患者BMI、FPG、LH、visfatin、Hp、HOMA-IR和FINS水平均显著高于非IR组,APN水平显著低于非IR组,差异均有统计学意义(P<0.05)。BMI、APN、visfatin、Hp均为诱发PCOS患者IR发生的危险因素(P<0.05)。血清APN、visfatin、Hp三者联合的曲线下面积(AUC)值以及特异度均高于单一指标预测(P<0.05)。结论PCOS患者均存在血清APN、visfatin、Haptoglobin水平的异常变化,三者有可能参与PCOS患者IR的发生发展,有望通过上述血清指标预测IR的发生。

haptoglobin基因型与疟疾发病风险不相关:meta分析(英文)

Haptoglobin（Hp）基因多态性与疟疾发病风险存在关联，但各研究结果不一致．本meta分析旨在探讨Hp基因多态性与疟疾发病风险的关系．在Pubmed数据库中查询文献，将包含Hp基因型频率的病例对照研究文献纳入本研究中，并计算疟疾发生危险性的优势比（Oddratio，OR）及其95％置信区间（confidence interval，CI）．最终查到符合要求的文献4篇，其中病例组1312例，对照组1018例．分析结果显示：在各遗传模式下Hp基因多态性与疟疾发病风险的相关性均不显著（加性模式：OR=1．882，95％CI：0．959～3．692，P=0．066；显性模式：OR=1．395，95％CI：0．733～2．656，P=0．311；隐性模型：OR=2．449，95％C／：0．921～6．508，P=0．073：共显性模型：（hp^1／hp^2 vs hp^2／hp^2）OR=0．951，95％CI：0．76～1．189，P=0．658；共显性模型（hp^1／hp^1 vs hp^2／hp^2）OR=2．336，95％CI：0．78～6．994，P=0．129）．并且Egger’s检验（P〉0．05）和Begg’S检验（P〉0．05）均显示不存在发表偏倚．综上所述，haptoglobin基因多态性对疟疾发病风险提高的影响可能并不大．

Progress on haptoglobin and metabolic diseases

Haptoglobin(Hp)is an acidic glycoprotein,existing in the serum and other body fluids of human beings and a variety of mammals.Hp is produced in the liver,white adipose tissue,and the kidney.The genetic polymorphisms and different phenotypes of Hp have different biological functions.Hp has antibacterial,antioxidant,and angiogenic effects and is associated with multiple diseases including simple obesity,vascular complications of diabetes mellitus,nonalcoholic fatty liver disease,hypertension,blood diseases,autoimmune diseases,and malignant tumors.Hp also participates in many life activities,indicating the importance of Hp in further studies.Previously,we found that the expression of serum Hp changed after treatment of simple obesity patients in clinical trials.However,the specific mechanism of Hp in patients with simple obesity is still unclear.The purpose of this article is to introduce recent research progress on Hp,emphasizing the relationship between Hp and the development of metabolic disease,which will improve the understanding of the functions of Hp underlying metabolic diseases and discuss future research directions.

Diagnostic accuracy of serum biochemical fibrosis markers in children with chronic hepatitis B evaluated by receiver operating characteristics analysis

METHODS： We determined the serum level of apolipoprotein A-I （APO A-I）, haptoglobin （HPT） and a-2 macroglobulin （A2I） with an automatic nephelometer in 63 children （age range 4-17 years, mean 10 years） with biopsy-verified chronic HBeAg-positive hepatitis B. Fibrosis stage and inflammation grade were assessed in a blinded fashion according to Batts and Ludwig. We defined mild liver fibrosis as a score ≤2 and advanced fibrosis as a score equal to 3. ROC analysis was used to calculate the power of the assays to detect advanced liver fibrosis （AccuROC, Canada）. RESULTS： Serum concentrations of APO A-I, HPT and A2M were not significantly different in patients with chronic hepatitis B compared to controls. However, APO A-I level of 1.19 ng/L had a sensitivity of 85.7% and a specificity of 60.7% （AUC = 0.7117, P = 0.035） to predict advanced fibrosis. All other serum biochemical markers and their combination did not allow a useful prediction. None of these markers was a good predictor of histologic inflammation. CONCLUSION： Apolipoprotein A-I may be a suitable serum marker to predict advanced liver fibrosis in children with chronic hepatitis B.

Involvement of haptoglobin in prevention of oxidative stress cause by hemoglobin in preeclampsia

Haptoglobin (Hp) is a hemoglobin (Hb) binding protein which plays an important role in neutralizing oxidation reactions stimulated by heme-derived iron. Differences in Hp types due to the polymorphic nature of the gene have led to the discovery that individuals carrying the Hp 2-2 genotype are at increased risk of developing vascular complications in the setting of diabetes. Preeclampsia is a pregnancy related disease that is thought to be caused by increases in oxidative stress. The role of Hp polymorphism is determining preeclampsia has been addressed by several clinical studies but the results have been contradictory. Larger longitudinal studies are needed to answer this important question.

N-linked glycoproteomic profiling in esophageal squamous cell carcinoma

BACKGROUND Mass spectrometry-based proteomics and glycomics reveal post-translational modifications providing significant biological insights beyond the scope of genomic sequencing.AIM To characterize the N-linked glycoproteomic profile in esophageal squamous cell carcinoma(ESCC)via two complementary approaches.METHODS Using tandem multilectin affinity chromatography for enrichment of N-linked glycoproteins,we performed N-linked glycoproteomic profiling in ESCC tissues by two-dimensional gel electrophoresis(2-DE)-based and isobaric tags for relative and absolute quantification(iTRAQ)labeling-based mass spectrometry quantitation in parallel,followed by validation of candidate glycoprotein biomarkers by Western blot.RESULTS 2-DE-based and iTRAQ labeling-based quantitation identified 24 and 402 differentially expressed N-linked glycoproteins,respectively,with 15 in common,demonstrating the outperformance of iTRAQ labeling-based quantitation over 2-DE and complementarity of these two approaches.Proteomaps showed the distinct compositions of functional categories between proteins and glycoproteins with differential expression associated with ESCC.Western blot analysis validated the up-regulation of total procathepsin D and high-mannose procathepsin D,and the downregulation of total haptoglobin,high-mannose clusterin,and GlcNAc/sialic acid-containing fraction of 14-3-3ζ in ESCC tissues.The serum levels of glycosylated fractions of clusterin,prolinearginine-rich end leucine-rich repeat protein,and haptoglobin in patients with ESCC were remarkably higher than those in healthy controls.CONCLUSION Our study provides insights into the aberrant N-linked glycoproteome associated with ESCC,which will be a valuable resource for future investigations.

Haematological Changes of Half-Marathon Runners in the Sub-Saharan African Environment

Background: Measurement of haematological parameters has been historically helpful in the diagnosis of many diseases in endurance sportsmen. The modifications of these parameters during endurance race have not yet been evaluated in many African countries. Objectives: To determine haematological values before and immediately after a half-marathon event, as well as within 24 hours after the race and to analyze the changes observed. Methods: A cross-sectional study was conducted from 10 to 21 August 2018 at Brazzaville, Congo. All measurements were confined to 76 male participants (39 specialists vs 37 no specialists of endurance race) in the Brazzaville half-marathon (21.1 km), aged between 19 - 39 years (mean age: 26.7 ± 2.6 years). Coulter profiles with differential white cell counts and haptoglobin levels were determined in venous sample before and after competitive half-marathon race. The same measurements were performed during the 24 hrs following the competition. Results: In the pre-race sample, mild anemia was detected in 12 subjects and mild thrombocytopenia in 7 subjects. Haptoglobin levels were reduced in 5 subjects. Haematological values, all post-race, varied significantly before and after race, particularly for RBC, Hb, Hct, PLT, MCV, MCH, MCHC, WBC, neutrophil counts, lymphocyte counts, monocyte counts, basophil counts, eosinophil counts and haptoglobin. These differences between specialists and no specialists were statistically (p Conclusion: Our data may help sport physicians, sport physiologists and trainers to better follow-up haematological reactions associated with the half-marathon race.

Interleukins and Acute Phase Proteins of Bovine Sera during Natural Helminth Burden in Ibadan Nigeria

Inflammatory reactions in the gastrointestinal tract play an important role in the pathogenesis of gastroenteritis in bovine helminthosis. This study determined the serum concentrations of cytokines induced acute phase proteins (Serum Amyloid A (SAA), Haptoglobin (Hp) and C-reactive protein (CRP)) and the levels of immunoreactive interleukins (IL-1, IL-2, IL-3, IL-4, IL-5 and IL-6) in cattle naturally infected with helminths. We sampled a total of 480 slaughtered cattle of both sexes in a major abattoir in Ibadan, Nigeria. Sedimentation, floatation and modified McMaster techniques were employed to determine the degrees of helminth infections. Animals with eggs per gram (epg) less than 200 were adjudged to be apparently healthy. The serum concentrations of interleukins and acute phase proteins were determined using the Technicon AutoAnalyzer Model AA II. It was found that mean SAA (μg/l) and CRP (%) levels were significantly (P 0.05). Therefore, some acute phase proteins are involved in the pathophysiology of bovine helminthosis and are closely related to the inflammatory activation of the disease. In lieu of these findings, it is suggested that systemic markers of inflammation can identify subjects at high risk of natural bovine helminthosis and that IL-6 and SAA may be used as indicators for bovine helminthosis.

Vitamin E and diabetic nephropathy in mice model and humans

Diabetes mellitus （DM） is associated with increased oxidative stress due to elevated glucose levels in the plasma. Glucose promotes glycosylation of both plasma and cellular proteins with increased risk for vascular events. Diabetic patients suffer from a higher incidence of cardiovascular complications such as diabetic ne-phropathy. Haptoglobin （Hp） is an antioxidant plasma protein which binds free hemoglobin, thus preventing heme-iron mediated oxidation. Two alleles exist at the Hp gene locus （1 and 2） encoding three possible Hp genotypes that differ in their antioxidant ability, and may respond differently to vitamin E treatment. Several clinical studies to have shown that Hp 1-1 genotype is a superior antioxidant to the Hp 2-2 genotype and Hp 2-2 genotype is associated with a higher incidence of cardiovascular disease. Vitamin E was found to have benefcial effect in patient and mice with Hp 2-2 geno-type. In this review we have summarized the results of our studies in patients with diabetic nephropathy treated with vitamin E and in diabetic mice with differ-ent haptoglobin genotypes.

Identification of novel biomarkers for adult-onset-immunodeficiency(AOID)syndrome using serum proteomics

Objective:To identify the candidate protein biomarkers of adult-onset-immunodeficiency(AOID) syndrome using serum proteomics. Methods:Screening and verification phases were performed in the study. A total of 97 serum samples were classified into three groups:AOID patients with opportunistic infections(active AOID),AOID patients without opportunistic infections(inactive AOID),and healthy control. In the screening phase,pooled sera collected from patients and healthy control in each group were separated by 2D-gel electrophoresis,analyzed for differentially expressed proteins and identified for biomarkers using LC/MS. In the verification phase,the protein candidates were selected for confirmation by western blotting. Results:The analysis revealed 35 differentially expressed proteins. Three proteins including haptoglobin,gelsolin,and transthyretin,were selected for verification. The results showed that the levels of haptoglobin in both active and inactive AOID groups were significantly higher than that in the control group,while the levels of gelsolin in the active AOID group were significantly lower than that in the inactive AOID group. The level of transthyretin in the active AOID group was also significantly lower than that in the control group. Conclusions:The comparison of serum proteins between the three groups revealed three candidates which are related to chronic inflammatory diseases. Haptoglobin and transthyretin biomarkers could be applied in clinical assessment for monitor of disease outcome,including for the study of AOID pathogenesis.

Targeted genotyping for the prediction of celiac disease autoimmunity development in patients with type 1 diabetes and their family members

BACKGROUND Patients with type 1 diabetes (T1D) and their first-degree relatives (FDRs) have an increased risk of developing celiac disease (CD) compared to the general population. This is largely explained by the shared association with major histocompatibility class II human leukocyte antigen (HLA) DQ2 and/or DQ8 between the two disease states. AIM To describe the frequency of CD autoimmunity (CDA) and the distribution of HLA and haptoglobin genotypes in patients with T1D and their FDRs. Additionally, we aimed at identifying predictors associated with an increased risk of developing CDA in patients with T1D and their family members. METHODS We obtained clinical information and blood samples from 1027 participants (302 with T1D and 725 FDRs) over a five-year period. Samples were tested for autoantibodies associated with CD, HLA-DQ alleles, and haptoglobin genotype.We fit univariate and multiple logistic regression models for CDA separately for subjects with T1D and for FDRs of subjects with T1D. RESULTS Implementation of a screening program increased the frequency of CDA by 2- fold in participants with T1D and 2.8-fold in their FDRs. Multivariate analysis found that, in participants with T1D, having both DR7-DQ2 and DR4-DQ8 was associated with an increased frequency of CDA. In FDRs of T1D patients, reported CD in the family was associated with an increased frequency of CDA during screening. Haptoglobin 2 genotype was not associated with developing CDA in the multivariate analysis. CONCLUSION Patients with T1D and their FDRs have a high frequency of CDA. Carrying both DR7-DQ2 and DR4-DQ8 was associated with development of CDA in patients with T1D.

Tyrosyl radical in haemoglobin and haptoglobin-haemoglobin complex:how does haptoglobin make haemoglobin less toxic?

One of the difficulties in creating a blood substitute on the basis of human haemoglobin(Hb) is the toxic nature of Hb when it is outside the safe environment of the red blood cells.The plasma protein haptoglobin(Hp) takes care of the Hb physiologically leaked into the plasma-it binds Hb and makes it much less toxic while retaining the Hb’s high oxygen transporting capacity.We used Electron Paramagnetic Resonance(EPR) spectroscopy to show that the protein bound radical induced by H2O2 in Hb and Hp-Hb complex is formed on the same tyrosine residue(s),but,in the complex,the radical is found in a more hydrophobic environment and decays slower than in unbound Hb,thus mitigating its oxidative capacity.The data obtained in this study might set new directions in engineering blood substitutes for transfusion that would have the oxygen transporting efficiency typical of Hb,but which would be non-toxic.

Detection of fucosylated haptoglobin using the 10-7G antibody as a biomarker for evaluating endoscopic remission in ulcerative colitis

BACKGROUND Inflammatory bowel disease(IBD)is a chronic,relapsing inflammation of the digestive tract.Although fecal and serum biomarkers have been extremely important and supportive for monitoring of IBD,their low sensitivity and high variability characteristics limit clinical efficacy.Thus,the establishment of better biomarkers is expected.Fucosylation is one of the most important glycosylation modifications of proteins.Fucosylated haptoglobin(Fuc-Hpt)is used as a biomarker for several cancers and inflammation-related diseases.We recently established a novel glycan monoclonal antibody(mAb),designated 10-7G,which recognizes Fuc-Hpt.We developed an enzyme-linked immunosorbent assay(ELISA)to measure serum levels of Fuc-Hpt(10-7G values).AIM To investigate the usefulness of the serum 10-7G values as a potential biomarker for monitoring disease activity in IBD.METHODS This was a case control study.Intestinal tissues of IBD patients(n=10)were examined immunohistochemically using the 10-7G mAb.We determined 10-7G values using serum from patients with ulcerative colitis(UC,n=110),Crohn’s disease(n=45),acute enteritis(AE,n=11),and healthy volunteers(HVs)who exhibited normal(n=20)or high(n=79)C-reactive protein(CRP)levels at medical check-up.We investigated the correlation between the 10-7G value and various clinical parameters of IBD patients by correlation analysis.Receiver operating characteristic(ROC)curve analysis was performed to evaluate the usefulness of the 10-7G values as a biomarker for clinical and endoscopic remission of UC compared to conventional serum biomarkers.RESULTS In the immunohistochemical analysis,positive 10-7G mAb staining was observed in lymphocytes infiltrating into inflammatory sites of the mucosal layer and lymphoid follicles.The 10-7G values were significantly higher in patients with IBD(P<0.001)and AE(P<0.05)compared with HVs.In addition,10-7G values were correlated with clinical examination parameters related to inflammation in patients with UC,particularly the CRP level(rs=0.525,P=0.003)and clinical activity index score(rs=0.435,P=0.038).However,there was no correlation between 10-7G values and CRP in HVs with high CRP levels,suggesting that the 10-7G values is not the same as a general inflammation biomarker.ROC curve analysis showed that area under the curve(AUC)value of 10-7G values for the diagnosis of endoscopic remission was higher than other biomarkers(AUC value=0.699).CONCLUSION The serum 10-7G value is a novel biomarker for evaluating intestinal inflammation and endoscopic mucosal healing in UC.

SERUM HAPTOGLOBIN SUPPRESSES T-LYMPHOCYTE FUNCTIONS FOLLOWING BURNS

It is well known that serum immunosuppressive factors play an important role in the mechanism of postburn immunosuppression.This study was intended to investigate the effect of haptoglobin, purified from the serum of burned patients by affinity chromatography,on the proliferation and interleukin-2(IL-2) secretion of normal murine thymocytes induced by ConA and the proliferation of IL-2 dependent cell line(CTLL-2) stimulated by recombinant human IL-2,so as to elucidate the role of serum haptoglobin in postburn T-lymphocyte dysfunction.The results showed that purified haptoglobin,at the level equivalent to the concentration found in serum of burned patients,significantly inhibited the proliferation and IL-2 secretion of normal murine thymocytes as well as CTLL-2 proliferation;whereas it exhibited no immunosuppressive effects at the level equivalent to the concentration found in serum of nomal volunteers.According to the results reported here,it is suggested that extraordinary increase in serum haptoglobin level may be an important factor of impaired T-lymphocyte responses following burns.

Genetic polymorphism and natural fertility in women

Objective: To investigate the cooperative interaction among five genetic systems (phosphoglucomutase locus 1, adenosine deaminase locus 1, acid phosphatase locus 1, adenylate kinase locus 1, and haptoglobin) concerning their effects on natural fertility in humans. Natural fertility has been evaluated by a model of age related differences between the distributions of types among pregnant women. Methods: A total of 137 nonsmoking consecutive puerperaes from the white population who had delivered their first born baby in the Maternity Department of S. Massimo Hospital of Penne were studied. The phenotypes of the five systems studied were determined by starch gel electrophoresis. Statistical analysis was performed using the statistical package for the social science. Results: There was a highly significant negative correlation between maternal age and the number of genetic factors showing a lower maternal age at the birth of the first child, which suggested a positive cooperative interaction among these factors concerning their effects on fertility. Conclusions:In the relationship of mother-fetus, besides nutritional factors, genetic factors involved in immunological interaction of the embryo with the mother are of paramount importance. Haptoglobin and adenosine deaminase locus 1 polymorphisms are involved in immune reactions and our data indicate that genetic variability within these systems gives a more important contribution to variation of human fertility as compared to acid phosphatase locus 1, phosphoglucomutase locus 1 and adenylate kinase locus 1 that are mainly involved in metabolic functions.

Interaction of haptoglobin with hemoglobin octamers based on the mutation <i>α</i>Asn78Cys or <i>β</i>Gly83Cys

Octameric hemoglobins have been developed by the introduction of surface cysteines in either the alpha or beta chain. Originally designed as a blood substitute, we report here the structure and ligand binding function;in addition the interaction with haptoglobin was studied. The recombinant Hbs (rHbs) with mutations alpha Asn78Cys or beta Gly83Cys spontaneously form octamers under conditions where the cysteines are oxidized. Oxygen binding curves and CO kinetic studies indicate a correct allosteric transition of the tetramers within the octamer. Crystallographic studies of the two rHbs show two disulfide bonds per octamer. Reducing agents may provoke dissociation to tetramers, but the octamers are stable when mixed with fresh human plasma, indicating that the reduction by plasma is slower than the oxidation by the dissolved oxygen, consistent with an enhanced stability. The octameric rHbs were also mixed with a solution of haptoglobin (Hp), which binds the dimers of Hb: there was little interaction for incubation times of 15 min;however, on longer timescales a complex was formed. Dynamic light scattering was used to follow the interaction of Hp with the alpha Asn78Cys octamer during 24 hours;a transition from a simple complex of 15 nm to a final size of 60 nm was observed. The results indicate a specific orientation of the αβ dimers may be of importance for the binding to haptoglobin.

Profiles of energy metabolites and haptoglobin in dairy cows under organic management in Alberta farms

Profiles of energy metabolites and haptoglobin (Hp) in dairy cows that are transitioned from conventional to organic management in various Alberta farms were compared with those of dairy cows managed conventionally at the University of Alberta dairy farm. Blood samples were collected during the following periods: Dry, 0 - 30, 30 - 60, and 60 - 90 days in milk (DIM, n = 7 cows). Concentrations of metabolites were evaluated by enzymatic colorimetric methods. Concentrations of Hp were determined by bovine ELISA kits. Data were analyzed by the mixed procedures of SAS. Concentrations of NEFA and BHBA in blood were elevated (P < 0.001) 0 to 30 d, intermediate 30 to 60, and 60 to 90 d, and lower in the dry period. In addition, BHBA was higher (P < 0.0001) at all stages of lactation in conventional than organic cows (e.g. 1289.4 ± 88.6 vs. 883.6 ± 47.5 μmol/L in conventional and organic cows at 0 - 30 d, respectively). Serum concentrations of cholesterol increased with increasing DIM and returned to nadir levels during dry period and was higher (P < 0.0001) in conventional than organic cows. Low glucose concentrations were observed 0 to 30 d, levels were intermediate 30 to 60 and 60 to 90 d, and peaked during the dry period (P < 0.54) between conventional and organic cows. Lactate did not (P < 0.24) vary with DIM or day × farm type but was higher (P < 0.0001) in organic cows than in conventional cows. Serum concentrations of Hp were elevated during dry period;reached peak levels 0 to 30 d and decreased gradually with increasing days postpartum and were much higher at all periods in conventional than organic cows. Overall, concentrations of Hp were 528.1 ± 45.2 μg/mL in conventional cows vs. 261.1 ± 16.9 μg/mL in organic cows (P < 0.0001). Taken together, these data indicate that metabolic changes associated with initiation of lactation are preceded by an acute phase response in dairy cows, and that cows in organic systems seem to be healthier than cows under conventional systems. These differences might be due to differences in nutritional management in the two systems.