Decreased Serum Wnt Antagonist Levels in Patients With Active Acromegaly.

OBJECTIVE: The Wnt signaling pathway is an important modulator of bone metabolism. This study aims to clarify the changes in Wnt antagonists in active and biochemically controlled acromegalic patients. METHODS: We recruited 77 patients recently diagnosed with acromegaly. Of those, 41 patients with complete follow-up data were included. Thirty healthy patients matched for age, sex, and body mass index served as controls. At baseline and posttreatment, Wnt antagonists (sclerostin [SOST], dickkopf-related protein 1 [DKK-1], and Wnt inhibitory factor 1 [WIF-1]), bone turnover markers (osteocalcin, procollagen type 1 N-terminal propeptide [P1NP], and C-terminal telopeptide of type 1 collagen [CTX]) and the bone remodeling index were investigated. RESULTS: Acromegalic patients had higher serum osteocalcin, P1NP, and CTX and a higher bone remodeling index than controls (P < .01). Serum SOST, DKK-1, and WIF-1 levels were significantly decreased in patients compared to controls (all P < .01). Serum SOST and WIF-1 levels were negatively correlated with growth hormone levels; SOST levels were positively correlated with WIF-1. After treatment, serum bone turnover markers and the bone remodeling index decreased, while SOST and WIF-1 significantly increased (P < .05). DKK-1 levels did not change compared to baseline (P > .05). In biochemically controlled patients, SOST and WIF-1 levels and bone turnover markers were restored and did not differ from those of the control participants (all P > .05). CONCLUSION: Patients with active acromegaly exhibited significantly decreased Wnt antagonist levels. The reduction in Wnt antagonists is a compensatory mechanism to counteract increased bone fragility in active acromegaly.

Cardiac Wnt5a and Wnt11 promote fibrosis by the crosstalk of FZD5 and EGFR signaling under pressure overload.

Progressive cardiac fibrosis accelerates the development of heart failure. Here, we aimed to explore serum Wnt5a and Wnt11 levels in hypertension patients, the roles of Wnt5a and Wnt11 in cardiac fibrosis and potential mechanisms under pressure overload. The pressure overload mouse model was built by transverse aortic constriction (TAC). Cardiac fibrosis was analyzed by Masson's staining. Serum Wnt5a or Wnt11 was elevated and associated with diastolic dysfunction in hypertension patients. TAC enhanced the expression and secretion of Wnt5a or Wnt11 from cardiomyocytes (CMs), cardiac fibroblasts (CFs), and cardiac microvascular endothelial cells (CMECs). Knockdown of Wnt5a and Wnt11 greatly improved cardiac fibrosis and function at 4 weeks after TAC. In vitro, shWnt5a or shWnt11 lentivirus transfection inhibited pro-fibrotic effects in CFs under mechanical stretch (MS). Similarly, conditional medium from stretched-CMs transfected with shWnt5a or shWnt11 lentivirus significantly suppressed the pro-fibrotic effects induced by conditional medium from stretched-CMs. These data suggested that CMs- or CFs-derived Wnt5a or Wnt11 showed a pro-fibrotic effect under pressure overload. In vitro, exogenous Wnt5a or Wnt11 activated ERK and p38 (fibrotic-related signaling) pathway, promoted the phosphorylation of EGFR, and increased the expression of Frizzled 5 (FZD5) in CFs. Inhibition or knockdown of EGFR greatly attenuated the increased FZD5, p-p38, and p-ERK levels, and the pro-fibrotic effect induced by Wnt5a or Wnt11 in CFs. Si-FZD5 transfection suppressed the increased p-EGFR level, and the fibrotic-related effects in CFs treated with Wnt5a or Wnt11. In conclusion, pressure overload enhances the secretion of Wnt5a or Wnt11 from CMs and CFs which promotes cardiac fibrosis by activation the crosstalk of FZD5 and EGFR. Thus, Wnt5a or Wnt11 may be a novel therapeutic target for the prevention of cardiac fibrosis under pressure overload.

Secreted Wnt antagonists in scrub typhus.

BACKGROUND: The mechanisms that control local and systemic inflammation in scrub typhus have only been partially elucidated. The wingless (Wnt) signaling pathways are emerging as important regulators of inflammation and infection, but have not been investigated in scrub typhus. METHODOLOGY/PRINCIPAL FINDINGS: Plasma levels of secreted Wnt antagonists (i.e. DKK-1, sFRP-3, WIF-1 and SOST) were analyzed in patients with scrub typhus (n = 129), patients with similar febrile illness without O. tsutsugamushi infection (n = 31), febrile infectious disease controls, and in healthy controls (n = 31) from the same area of South India, and were correlated to markers of inflammation, immune and endothelial cell activation as well as for their association with organ specific dysfunction and mortality in these patients. We found i) Levels of SOST and in particular sFRP-3 and WIF-1 were markedly increased and DKK-1 decreased in scrub typhus patients at admission to the hospital compared to healthy controls. ii) In recovering scrub typhus patients, SOST, sFRP-3 and WIF-1 decreased and DKK-1 increased. iii) SOST was positively correlated with markers of monocyte/macrophage and endothelial/vascular activation as well as with renal dysfunction and poor outcome iv) Finally, regulation of Wnt pathways by O. tsutsugamushi in vitro in monocytes and ex vivo in mononuclear cells isolated from patients with scrub typhus, as evaluated by gene expression studies available in public repositories, revealed markedly attenuated canonical Wnt signaling. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that scrub typhus is characterized by attenuated Wnt signaling possibly involving dysregulated levels of several secreted pathway antagonists. The secreted Wnt antagonist SOST was strongly associated with renal dysfunction and poor prognosis in these patients.

Relationship of Wnt pathway activity and organ involvement in scleroderma types.

OBJECTIVE: Scleroderma (SSc) is a chronic inflammatory autoimmune disease characterized by fibrosis in the skin and internal organs. In SSc, the heart, lung, kidney, gastrointestinal (GIS) system, muscle, and peri-articular structures are damaged. There is no study of the relationship between SSc type, stage, pathogenesis, organ involvement, and Wnt signaling. In this study, we aimed to show the relationship of the Wnt gene family and antagonists in SSc subtypes and different organ involvement. METHODS: Eighty-five SSc patients and 77 controls were included in this study. The gene expressions and protein levels of the Wnt family and antagonists were analyzed from blood samples. The relationship between these parameters and disease stage, type, and organ involvement were evaluated. RESULTS: Wnt-1, Wnt-10b, Wnt-2, and Wnt-6 gene expressions are increased and Axin-2, DKK-1, and Kremen protein expressions are decreased in SSc. Wnt-3a and Wnt-10a gene expressions are increased in generalized SSc compared to limited SSc. Wnt-1, Wnt-2 gene expressions are increased significantly in pulmonary arterial hypertension (PAH)(+) SSc compared to PAH(-) SSc. There was a positive correlation between the modified Rodnan skin score and Wnt-2 in SSc. There was a significant positive correlation between GIS involvement score and Wnt-1, Wnt-2, Wnt-4, Wnt-8a, Wnt-9b in SSc. CONCLUSION: Wnt-1 and Wnt-2 were found higher in scleroderma and organ involvement. They may play a role in the pathogenesis of the disease.

Canonical Wnts Mediate CD8+ T Cell Noncytolytic Anti-HIV-1 Activity and Correlate with HIV-1 Clinical Status.

CD8+ T cells do not rely solely on cytotoxic functions for significant HIV control. Moreover, the noncytotoxic CD8+ T cell antiviral response is a primary mediator of natural HIV control such as that seen in HIV elite controllers and long-term nonprogressors that does not require combined antiretroviral therapy. In this study, we investigated the biological factors contributing to the noncytotoxic control of HIV replication mediated by primary human CD8+ T cells. We report that canonical Wnt signaling inhibits HIV transcription in an MHC-independent, noncytotoxic manner and that mediators of this pathway correlate with HIV controller clinical status. We show that CD8+ T cells express all 19 Wnts and CD8+ T cell-conditioned medium (CM) induced canonical Wnt signaling in infected recipient cells while simultaneously inhibiting HIV transcription. Antagonizing canonical Wnt activity in CD8+ T cell CM resulted in increased HIV transcription in infected cells. Further, Wnt2b expression was upregulated in HIV controllers versus viremic patients, and in vitro depletion of Wnt2b and/or Wnt9b from CD8+ CM reversed HIV inhibitory activity. Finally, plasma concentration of Dkk-1, an antagonist of canonical Wnt signaling, was higher in viremic patients with lower CD4 counts. This study demonstrates that canonical Wnt signaling inhibits HIV and significantly correlates with HIV controller status.

Differences in Serum Biomarkers Between Combined Glucosamine and Chondroitin Versus Celecoxib in a Randomized, Double-blind Trial in Osteoarthritis Patients.

BACKGROUND: Non-steroidal anti-inflammatory drugs, e.g., celecoxib, are commonly used for inflammatory conditions, but can be associated with adverse effects. Combined glucosamine hydrochloride plus chondroitin sulfate (GH+CS) are commonly used for joint pain and have no known adverse effects. Evidence from in vitro, animal and human studies suggest that GH+CS have anti-inflammatory activity, among other mechanisms of action. OBJECTIVE: We evaluated the effects of GH+CS versus celecoxib on a panel of 20 serum proteins involved in inflammation and other metabolic pathways. METHODS: Samples were from a randomized, parallel, double-blind trial of pharmaceutical grade 1500 mg GH + 1200 mg CS (n=96) versus 200 mg celecoxib daily (n=93) for 6- months in knee osteoarthritis (OA) patients. Linear mixed models adjusted for age, sex, body mass index, baseline serum protein values, and rescue medicine use assessed the intervention effects of each treatment arm adjusting for multiple testing. RESULTS: All serum proteins except WNT16 were lower after treatment with GH+CS, while about half increased after celecoxib. Serum IL-6 was significantly reduced (by 9%, P=0.001) after GH+CS, and satisfied the FDR<0.05 threshold. CCL20, CSF3, and WNT16 increased after celecoxib (by 7%, 9% and 9%, respectively, P<0.05), but these serum proteins were no longer statistically significant after controlling for multiple testing. CONCLUSION: The results of this study using samples from a previously conducted trial in OA patients, demonstrate that GH+CS reduces circulating IL-6, an inflammatory cytokine, but is otherwise comparable to celecoxib with regard to effects on other circulating protein biomarkers.

Osteoprotegrin interacts with biomarkers and cytokines that have roles in osteoporosis, skin fibrosis, and vasculopathy in systemic sclerosis: A potential multifaceted relationship between OPG/RANKL/TRAIL and Wnt inhibitors.

Objectives: We explored the interactions of osteoprotegerin (OPG) with biomarkers of bone turnover and cytokines, including soluble receptor activator for nuclear factor kappa beta ligand (sRANKL), tumor necrosis factor-related apoptosis-induced ligand (TRAIL), and Wnt inhibitors in osteoporosis, vasculopathy and fibrosis related to systemic sclerosis (SSc). Methods: The study included 46 SSc patients and 30 healthy controls. Skin thickness, pulmonary fibrosis and/or hypertension, digital ulcers, and calcinosis cutis of SSc patients were assessed. We determined bone mineral density (BMD), and OPG, sRANKL, TRAIL, secreted frizzled-related protein 1 (sFRP-1), Dickkopf-related protein 1 (DKK-1), sclerostin in the serum of both patients and controls. Results: OPG, sclerostin, and sFRP-1 levels were similar between patients and controls (P > 0.05). Femoral neck and lumbar spine BMD and vitamin D levels were lower, and the OC, NTX, sRANKL, DKK1 and TRAIL levels were significantly higher, in patients than in controls (p < 0.05). In subgroup analysis, patients with higher modified Rodnan skin score (mRodnan) had higher DKK-1, sclerostin, and TRAIL levels (p < 0.05); those with diffuse SSc subtype had lower BMD values than those with limited SSc (p < 0.05). Skin and pulmonary fibrosis linked negatively with BMD measures. Conclusion: we showed that sRANKL levels were higher and correlated with bone turnover markers. It may be related to osteoporosis in SSc. The OPG level was unaltered in SSc patients. Higher TRAIL levels associated with skin thickness may indicate vascular dysfunction or injury. Higher DKK-1 and sclerostin levels may be related to a reactive increase in cells and be prominently linked to fibrosis in SSc.

Role of Wnt/ß-catenin and RANKL/OPG in bone healing of diabetic Charcot arthropathy patients.

BACKGROUND AND PURPOSE: Charcot neuropathy is characterized by bone destruction in a foot leading to deformity, instability, and risk of amputation. Little is known about the pathogenic mechanisms. We hypothesized that the bone-regulating Wnt/ß-catenin and RANKL/OPG pathways have a role in Charcot arthropathy. PATIENTS AND METHODS: 24 consecutive Charcot patients were treated by off-loading, and monitored for 2 years by repeated foot radiography, MRI, and circulating levels of sclerostin, dickkopf-1, Wnt inhibitory factor-1, Wnt ligand-1, OPG, and RANKL. 20 neuropathic diabetic controls and 20 healthy controls served as the reference. RESULTS: Levels of sclerostin, Dkk-1 and Wnt-1, but not of Wif-1, were significantly lower in Charcot patients than in the diabetic controls at inclusion. Dkk-1 and Wnt-1 levels responded to off-loading by increasing. Sclerostin levels were significantly higher in the diabetic controls than in the other groups whereas Wif-1 levels were significantly higher in the healthy controls than in the other groups. OPG and RANKL levels were significantly higher in the Charcot patients than in the other groups at inclusion, but decreased to the levels in healthy controls at 2 years. OPG/RANKL ratio was balanced in all groups at inclusion, and it remained balanced in Charcot patients on repeated measurement throughout the study. INTERPRETATION: High plasma RANKL and OPG levels at diagnosis of Charcot suggest that there is high bone remodeling activity before gradually normalizing after off-loading treatment. The consistently balanced OPG/RANKL ratio in Charcot patients suggests that there is low-key net bone building activity by this pathway following diagnosis and treatment. Inter-group differences at diagnosis and changes in Wnt signaling following off-loading treatment were sufficiently large to be reflected by systemic levels, indicating that this pathway has a role in bone remodeling and bone repair activity in Charcot patients. This is of particular clinical relevance considering the recent emergence of promising drugs that target this system.

Roles of circulating WNT-signaling proteins and WNT-inhibitors in human adiposity, insulin resistance, insulin secretion, and inflammation.

Wingless-type MMTV integration site family member (WNT) signaling and WNT-inhibitors have been implicated in regulation of adipogenesis, insulin resistance, pancreatic function, and inflammation. Our goal was to determine serum proteins involved in WNT signaling (WNT5 and WISP2) and WNT inhibition (SFRP4 and SFRP5) as they relate to obesity, serum adipokines, insulin resistance, insulin secretion, and inflammation in humans. Study population comprised 57 insulin resistant women with polycystic ovary syndrome (PCOS) and 27 reference women. In a cross-sectional study, blood samples were obtained at fasting, during oral, and frequently sampled intravenous glucose tolerance tests. Serum WNT5, WISP2, and SFRP4 concentrations did not differ between PCOS vs. reference women. Serum WNT5 correlated inversely with weight both in PCOS and reference women, and correlated directly with insulin response during oral glucose tolerance test in PCOS women. Serum WISP2 correlated directly with fatty acid binding protein 4. Serum SFRP5 did not differ between obese (n=32) vs. nonobese (n=25) PCOS women, but reference women had lower SFRP5 (p<5×10(-6) as compared to both PCOS groups). Serum SFRP5 correlated inversely with IL-1ß, TNF-α, cholesterol, and apoprotein B. These findings demonstrated that WNT5 correlated inversely with adiposity and directly with insulin response, and the WNT-inhibitor SFRP5 may be anti-inflammatory. Better understanding of the role of WNT signaling in obesity, insulin resistance, insulin secretion, lipoprotein metabolism, and inflammation is important for prevention and treatment of metabolic syndrome, diabetes and cardiovascular disease.

Serum wnt5a is a predictor for the prognosis of acute on chronic hepatitis B liver failure.

OBJECTIVES: To find a biomarker to predict the prognosis of acute on chronic hepatitis B liver failure (ACHBLF). METHODS: Expression gene profiles in wnt pathway were determined in serum from 63 patients with ACHBLF, 60 patients with chronic hepatitis B (CHB) and 30 healthy controls (HCs). RESULTS: Serum wnt5a concentration of 1.553 ng/ml showed a poor prognosis with a sensitivity of 69.23% and a specificity of 83.33% in ACHBLF patients. CONCLUSIONS: Serum wnt5a gene expression might be a potential biomarker for predicting the prognosis of ACHBLF.

The wingless-related integration site-5a/secreted frizzled-related protein-5 system is dysregulated in human sepsis.

Sepsis and type 2 diabetes exhibit insulin resistance as a common phenotype. In type 2 diabetes we and others have recently provided evidence that alterations of the proinflammatory wingless-related integration site (wnt)-5a/anti-inflammatory secreted frizzled-related protein (sFRP)-5 system are involved in the pathogenesis of insulin resistance. The aim of the present study was to investigate whether this novel cytokine system is dysregulated in human sepsis, which may indicate a potential mechanism linking inflammation to metabolism. In this single-centre prospective observational study, critically ill adult septic patients were examined and proinflammatory wnt5a and wnt5a inhibitor sFRP5 were measured in serum samples by enzyme-linked immunosorbent assay (ELISA) at admission to the intensive care unit (ICU) and 5 days later. Sixty sepsis patients were included, and 30 healthy individuals served as controls. Wnt5a levels were found to be increased significantly in septic patients compared to healthy controls (2·21 ± 0·33 versus 0·32 ± 0·03 ng/ml, P < 0·0001). In contrast, sFRP5 was not altered significantly in septic patients (19·72 ± 3·06 versus 17·48 ± 6·38 ng/ml, P = 0·07). On admission to the ICU, wnt5a levels exhibited a significant positive correlation with the leucocyte count (rs = 0·3797, P = 0·004). Interestingly, in patients recovering from sepsis, wnt5a levels declined significantly within 5 days (2·17 ± 0·38-1·03 ± 0·28 ng/ml, P < 0·01). In contrast, if sepsis was worsening, wnt5a levels increased in the same time-period by trend (2·34 ± 0·59-3·25 ± 1·02 ng/ml, P > 0·05). sFRP5 levels did not change significantly throughout the study period. The wnt5a/sFRP5 system is altered in human sepsis and might therefore be of interest for future studies on molecular pathophysiology of this common human disease.

Activation of noncanonical Wnt signaling through WNT5A in visceral adipose tissue of obese subjects is related to inflammation.

CONTEXT: Wingless-type mouse mammary tumor virus integration site family (WNT)-5A is a glycoprotein involved in the regulation of the inflammatory response by activating the noncanonical Wnt signaling pathway. Secreted frizzled-related protein (SFRP)-5 acts as a decoy receptor that binds and sequesters WNT5A, preventing activation of frizzled receptors and attenuating the noncanonical Wnt signaling. OBJECTIVE: The aim of the study was to evaluate the involvement of WNT5A and SFRP5 in obesity and obesity-related comorbidities as well as to explore their effect in visceral adipose tissue inflammation. PATIENTS AND METHODS: Samples obtained from 90 subjects were used. Circulating and gene expression levels of WNT5A and SFRP5 were analyzed in different metabolic tissues. The effect of TNF-α and lipopolysaccharide on the transcript levels of WNT5A and SFRP5 in adipocytes was explored. We also investigated whether WNT5A itself can activate an inflammatory response. RESULTS: Increased circulating levels of WNT5A in obese patients (P < .05) were decreased (P < .001) after gastric bypass. In this line, WNT5A mRNA in visceral adipose tissue was increased (P < .05) in obese patients with gene expression levels of SFRP5 being down-regulated (P < .05). WNT5A mRNA expression was significantly enhanced (P < .01) by lipopolysaccharide and TNF-α treatment, whereas no effects were found in SFRP5 gene expression levels. Furthermore, exogenous WNT5A induced (P < .05) IL-6, IL1B, MMP2, MMP9, and SSP1 mRNA expression in human adipocyte cultures. CONCLUSIONS: Activation of noncanonical Wnt signaling through the up-regulation of WNT5A and down-regulation of SFRP5 may promote a proinflammatory state in visceral adipose tissue contributing to the development of obesity-associated comorbidities.

Wnt5a: a potential factor linking psoriasis to metabolic complications.

Psoriasis is associated with comorbidity including obesity, insulin resistance and diabetes mellitus type 2. In obesity, the protein wingless-type MMTV integration site Family, Member 5a (wnt5a) is released from adipose tissue macrophages and was shown to be of importance in the development of insulin resistance. As wnt5a was also shown to be upregulated in psoriatic skin lesions, we investigated whether wnt5a and its counterpart secreted frizzled-related protein 5 are altered in the circulation of lean and obese patients with psoriasis compared with lean and obese healthy volunteers by measuring serum concentrations of both proteins. Our results showed that wnt5a was significantly higher in lean patients with psoriasis (0.096 ng/ml; SD 0.12) compared with lean healthy controls (0.020 ng/ml; SD 0.04; P ≤ 0.01) as well as in obese patients (0.177 ng/ml; SD 0.14) compared with obese healthy controls (0.011 ng/ml; SD 0.03; P ≤ 0.001). Therefore, we suggest that in psoriasis, an increase in wnt5a may contribute to the development of metabolic comorbidity.

Balanced duo of anti-inflammatory SFRP5 and proinflammatory WNT5A in children.

BACKGROUND: Secreted frizzled-related protein 5 (SFRP5) is an adipokine protecting against obesity-related insulin resistance and diabetes. SFRP5 binds to wingless type mouse mammary tumor virus (MMTV) integration site family member 5A (WNT5A) to improve insulin sensitivity. We performed the first study of SFRP5 and WNT5A simultaneously in children. METHODS: Prepubertal children (n = 342) were assessed for circulating SFRP5 (all subjects) and circulating WNT5A (210 subjects), and associations were sought with metabolic markers. In conditioned media of adipose tissue explants from 12 additional children, SFRP5 and WNT5A were studied further. RESULTS: The concentrations of SFRP5 and WNT5A correlated positively in serum and in conditioned media (all P < 0.001). Lower level of circulating SFRP5 (lowest quartile) was associated with higher BMI (15% increase, P < 0.0001) and lower level of high-molecular-weight adiponectin (26% decrease, P = 0.002). Circulating WNT5A related closely with insulin resistance assessed by the homeostasis model assessment for insulin resistance and hepatic markers (alanine transaminase and gamma glutamyl transpeptidase), particularly in children with lower circulating SFRP5 levels (all P < 0.004). CONCLUSION: SFRP5 and WNT5A comprise a balanced duo that may regulate metabolic homeostasis in prepubertal children.

Wnt5a, TLR2 and TLR4 are elevated in advanced human atherosclerotic lesions.

OBJECTIVE AND DESIGN: Atherosclerosis (ATH) is a chronic inflammatory disease that involves cascades of signaling events mediated by various effector proteins. Here we sought to determine if the expression of Wnt5a, a secreted glycoprotein, is altered in discrete regions of the arterial plaque. METHODS: Atherosclerotic plaque tissues from 14 human subjects undergoing elective carotid endarterectomy were used in this study. Immunohistochemistry and laser capture microdissection combined with quantitative real-time PCR were used to determine the expression of Wnt5a and Toll-like receptors (TLRs) in different sections of the arterial lesions. Atherosclerotic serum samples (n = 30) and serum from healthy subjects (n = 16) were quantified for Wnt5a using an enzyme-linked immunosorbent assay (ELISA). RESULTS: The data analysis revealed that Wnt5a transcripts and protein were elevated in advanced arterial lesions relative to less advanced arterial lesions; that Wnt5a expression correlated with the presence of TLR4 and TLR2 transcripts; and that the average amount of Wnt5a protein present in atherosclerotic patient serum was significantly higher compared to healthy controls. CONCLUSIONS: This study is the first to provide evidence that the expression of Wnt5a increases as the disease progresses to a more advanced stage, and that this expression is coincident with that of TLR2 and TLR4. In addition, we found that the average Wnt5a levels in the serum of atherosclerotic patients are elevated relative to healthy controls, which is consistent with the hypothesis that Wnt5a plays a role in ATH.

Circulating secreted frizzled-related protein 5 (Sfrp5) and wingless-type MMTV integration site family member 5a (Wnt5a) levels in patients with type 2 diabetes mellitus.

BACKGROUND: Secreted frizzled-related protein 5 (Sfrp5), an endogenous inhibitor of wingless-type MMTV integration site family (Wnt) signalling, is an anti-inflammatory adipokine whose expression is perturbed in models of obesity and type 2 diabetes mellitus (T2DM). Wnt member 5a (Wnt5a) is a representative ligand, and recent reports suggest that Wnt5a is involved in inflammatory diseases and metabolic disorders. The aim of this study was to investigate whether plasma Wnt5a and Sfrp5 levels are altered in patients with T2DM. METHODS: Plasma Sfrp5 and Wnt5a concentrations were measured through enzyme-linked immunosorbent assay in type 2 diabetic and nondiabetic subjects. RESULTS: A total of 82 patients with T2DM and 42 nondiabetic subjects were studied. Plasma Sfrp5 levels were found to be elevated in patients with T2DM (9.4 ± 9.0 vs 7.4 ± 10.9 ng/mL, p = 0.006). In contrast, Wnt5a levels were decreased (6.8 ± 12.6 vs 9.1 ± 4.0 ng/dL, p < 0.001). Increasing concentrations of Sfrp5 were independently and significantly associated with T2DM. Multiple logistic regression analysis revealed Sfrp5 as an independent association factor for T2DM, even after full adjustment of known biomarkers. In a multiple linear regression analysis, only the fasting glucose level was positively associated with the plasma Sfrp5 level. CONCLUSIONS: Our results indicate that Sfrp5 may play a role in the pathogenesis of T2DM.

Sfrp5 correlates with insulin resistance and oxidative stress.

BACKGROUND: Secreted frizzled-related protein 5 (Sfrp5) has been described as novel adipokine in mice with insulin-sensitising and anti-inflammatory properties similar to adiponectin. The aim of this study was to compare serum concentrations and determinants of Sfrp5, its pro-inflammatory antagonist wingless-type MMTV integration site family member (Wnt)5a and adiponectin in humans and their regulation by coffee. MATERIAL AND METHODS: Serum concentrations of Sfrp5, Wnt5a and adiponectin were measured in 47 individuals who participated in a coffee intervention study. Associations with demographic, metabolic and immunological variables and regulation of serum levels by different amounts of daily coffee intake were analysed. RESULTS: At baseline, fasting serum Sfrp5 levels ranged between 96 and 4056 ng/mL. Sfrp5 was directly correlated with a surrogate of insulin resistance (homeostasis model assessment of insulin resistance/HOMA-IR; r = 0·32, P < 0·05) and with the oxidative stress markers 8-isoprostane (r = 0·44, P < 0·01) and nitrotyrosine (r = 0·52, P < 0·001). Adiponectin showed inverse correlations with several indices of insulin resistance (e.g. HOMA-IR, Stumvoll index; all P < 0·05) and a direct correlation with the anti-atherogenic apolipoprotein A-I (r = 0·56, P < 0·001). Coffee did not affect serum concentrations of Sfrp5. Serum Wnt5a concentrations were below the detection limit (0·02 ng/mL) in 81% of the study participants. CONCLUSIONS: In contrast to obese mouse models, serum Sfrp5 was directly related to HOMA-IR and oxidative stress in humans, but not with apolipoproteins, and thus, associations differed from those found for circulating adiponectin. These differences between Sfrp5 and adiponectin might be explained by differences in the investigated species.

Expression profile of Wnt molecules in leukemic cells from Iranian patients with acute myeloblastic leukemia.

BACKGROUND: Wnt molecules play a key role in growth, proliferation and development of some embryonic and adult organs as well as hematopoietic stem cells. Wnt signaling pathways are aberrantly activated in many tumor types, including solid tumors and hematologic malignancies. OBJECTIVE: To investigate the expression profile of a large number of Wnt genes in leukemic cells from Iranian patients with acute myeloblastic leukemia. METHODS: RT-PCR method was used to determine the Wnt genes expression in bone marrow (BM) and/or peripheral blood (PB) samples from 16 patients with AML and PB samples of 36 normal subjects. RESULTS: Among 14 Wnt molecules included in this study, Wnt-7A and Wnt-10A were significantly down-regulated (p = 0.002 and p < 0.0001, respectively) and Wnt-3 was significantly over-expressed (p < 0.02) in AML patients compared to normal subjects. No significant association was found between Wnt expression and FAB classification of the patients. CONCLUSION: Our results demonstrated for the first time aberrant expression of Wnt-7A, Wnt-10A and Wnt-3 genes in Iranian AML patients. This may be of relevance to the tumorigenesis process in this malignancy.

Identification of interleukin-13 related biomarkers using peripheral blood mononuclear cells.

Asthma is a chronic disorder characterized by airway inflammation, reversible bronchial obstruction, hyper-responsiveness and remodelling. Data from human in vitro studies and experimental in vivo models of asthma has implicated interleukin (IL)-13 in the asthma phenotype suggesting that a therapeutic agent against it could be effective in treating asthma. The role of biomarkers is becoming increasingly important in the clinical development of therapeutics. Here we describe the use of the GeneChip((R)) DNA microarray technology platform to explore and identify potential response to therapy biomarkers that are associated with the biology of IL-13. Peripheral blood mononuclear cells (PBMCs) from eight healthy donors were cultured in the presence of IL-13, IL-4, an anti-IL-13 monoclonal antibody (mAb) or an isotype control mAb, and RNA from the treated cells was subjected to microarray analysis. The results revealed a number of genes, such as CCL17 (TARC), CCL22 (MDC), CCL23 (MPIF-1), CCL26 (eotaxin 3) and WNT5A (human wingless-type MMTV integration site family member 5A), that showed increased expression in the IL-13 and IL-4 treatment groups. Real-time polymerase chain reaction (PCR) subsequently confirmed these results. A follow-up study in PBMCs from five additional healthy donors showed that the neutralization of IL-13 completely blocked IL-13-induced TARC, MDC and eotaxin 3 production at the protein level. These data suggest that TARC, MDC, eotaxin 3, CCL23 and WNT5A if validated could serve as potential biomarkers for anti-IL-13 therapeutics.