The immunopharmacological properties of transforming growth factor beta

Serum IL-6 and TGF-β1 concentrations as diagnostic biomarkers in elderly male patients with osteoporosis

PURPOSE

This research is intended to evaluate the correlations of serum IL-6 and TGF-β1 concentrations with bone density and turnover markers as well as their diagnostic value in elderly male patients with osteoporosis (OP).

METHODS

A retrospective analysis was conducted on 335 elderly men (≥ 60 years; 90 with normal bone mass, 120 osteopenia cases, and 125 OP cases). Lumbar spine/femoral neck BMD values were measured using dual-energy X-ray absorptiometry. Correlations of serum IL-6 and TGF-β1 concentrations with bone density and bone turnover markers in OP patients were analyzed utilizing Pearson or Spearman correlation coefficients. Independent influencing factors for OP were identified by logistic multivariate regression analysis. The diagnostic value of serum IL-6 and TGF-β1 was assessed with ROC curves and MedCalc software.

RESULTS

Smoking history, drinking history, lumbar spine BMD, femoral neck BMD, PINP, and β-CTX markedly differed among the normal bone mass, osteopenia, and OP groups. Elevated IL-6 and reduced TGF-β1 concentrations were observed in serum samples of OP. Serum IL-6 concentrations was inversely associated with bone density markers but positively lined to bone turnover markers. Conversely, serum TGF-β1 was positively related to bone density markers but negatively associated with bone turnover markers. Smoking history, PINP, and IL-6, were identified as independent risk factors while lumbar spine BMD, femoral neck BMD, and TGF-β1 were independent protective markers for OP. The combined assessment of serum IL-6 and TGF-β1 showed superior diagnostic performance for OP.

CONCLUSION

Serum IL-6 in combination with TGF-β1 exhibits good diagnostic performance for OP.

LEVEL OF EVIDENCE

Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

TGF-β1 Provides Neuroprotection via Inhibition of Microglial Activation in 3-Acetylpyridine-Induced Cerebellar Ataxia Model Rats

Cerebellar ataxias (CAs) consist of a heterogeneous group of neurodegenerative diseases hallmarked by motor deficits and deterioration of the cerebellum and its associated circuitries. Neuroinflammatory responses are present in CA brain, but how neuroinflammation may contribute to CA pathogenesis remain unresolved. Here, we investigate whether transforming growth factor (TGF)-β1, which possesses anti-inflammatory and neuroprotective properties, can ameliorate the microglia-mediated neuroinflammation and thereby alleviate neurodegeneration in CA. In the current study, we administered TGF-β1 via the intracerebroventricle (ICV) in CA model rats, by intraperitoneal injection of 3-acetylpyridine (3-AP), to reveal the neuroprotective role of TGF-β1. The TGF-β1 administration after 3-AP injection ameliorated motor impairments and reduced the calbindin-positive neuron loss and apoptosis in the brain stem and cerebellum. Meanwhile, 3-AP induced microglial activation and inflammatory responses in vivo, which were determined by morphological alteration and an increase in expression of CD11b, enhancement of percentage of CD40 + and CD86 + microglial cells, upregulation of pro-inflammatory mediators, tumor necrosis factor (TNF)-α and interleukin (IL)-1β, and a downregulation of neurotrophic factor, insulin-like growth factor (IGF)-1 in the brain stem and cerebellum. TGF-β1 treatment significantly prevented all the changes caused by 3-AP. In addition, in vitro experiments, TGF-β1 directly attenuated 3-AP-induced microglial activation and inflammatory responses in primary cultures. Purkinje cell exposure to supernatants of primary microglia that had been treated with TGF-β1 reduced neuronal loss and apoptosis induced by 3-AP-treated microglial supernatants. Furthermore, the protective effect was similar to those treated with TNF-α-neutralizing antibody. These findings suggest that TGF-β1 protects against neurodegeneration in 3-AP-induced CA rats via inhibiting microglial activation and at least partly TNF-α release.

Dissecting the role of transforming growth factor-β1 in topmouth culter immunobiological activity: a fundamental functional analysis

Transforming growth factor-β1 (TGF-β1) has been proven to function primarily in mammalian immunobiological activity, but information regarding the immune role of TGF-β1 in teleosts is limited. In the present study, we describe the cDNA cloning and characterization of the TGF-β1 molecule in the topmouth culter. TGF-β1 is highly expressed in immune-related tissues of the culter, including the thymus, head kidney, and spleen. The recombinant culter TGF-β1 (cTGF-β1) was successfully expressed and purified in vitro, and the effects of cTGF-β1 on the mRNA expression of pro-inflammatory cytokines, such as TNF-α and IL-1β, in the absence or presence of LPS was determined in culter peripheral blood leukocytes. cTGF-β1 was found to have bipolar properties in inflammatory reactions. Additionally, to assess the immune role of teleost TGF-β1 in vivo, the expression of TGF-β1 in the culter thymus and spleen tissues induced by poly I:C were also examined. The expression of TGF-β1 was obviously up-regulated, as shown in the cell lines. However, the peak time of cTGF-β1 expression in the cell lines occurred significantly earlier than in the organic tissues under the same inducer, suggesting that the response of the teleost TGF-β1 molecule to exogenous infection depends on a more complicated signalling pathway in vivo than in vitro.

Cloning and primary immunological study of TGF-β1 and its receptors TβR I /TβR II in tilapia(Oreochromis niloticus)

The transforming growth factor β (TGF-β) superfamily plays critical roles in tumor suppression, cell proliferation and differentiation, tissue morphogenesis, lineage determination, cell migration and apoptosis. Recently, TGF-β1, one important member of TGF-β superfamily, is suggested as an immune regulator in the teleost. In this study, we cloned the cDNAs of TGF-β1 and its receptors, TβR I and TβR II (including three isoforms) from tilapia (Genbank accession numbers: KP754231- KP754235). A tissue distribution profile analysis indicated that TGF-β1 was highly expressed in the head kidney, gill, spleen, kidney and PBLs (peripheral blood leukocytes); TβR I only showed considerable expression in the liver; and TβR II-2 was highly expressed in the kidney, gill, liver, head kidney and heart. We determined that the mRNA expressions of TGF-β and TβR I /TβR II-2 were significantly increased in tilapia head kidney and spleen leukocytes by the stimulation of Lipopolysaccharide (LPS) or Poly I: C. We also examined their expressions in the spleen and head kidney of tilapia after IP injection of streptococcus agalactiae. The results showed that the mRNA expressions of these three genes all increased in the head kidney as early as 6 h post infection, and in the spleen 3 d post infection. In addition, the protein level of TGF-β1 was also up-regulated in the head kidney and the spleen after infection. Taken together, our data indicate that the TGF-β1-TβR I /TβR II-2 system functions potentially in tilapia immune system.

Protection of TGF-β1 against neuroinflammation and neurodegeneration in Aβ1-42-induced Alzheimer's disease model rats

Neuroinflammation has been reported to be associated with Alzheimer’s disease (AD) pathogenesis. Neuroinflammation is generally considered as an outcome of glial activation; however, we recently demonstrated that T helper (Th)17 cells, a subpopulation of proinflammatory CD4+ T cells, are also involved in AD pathogenesis. Transforming growth factor (TGF)-β1, a cytokine that can be expressed in the brain, can be immunosuppressive, but its effects on lymphocyte-mediated neuroinflammation in AD pathogenesis have not been well addressed. In the current study we administered TGF-β1 via intracerebroventricle (ICV) and intranasal (IN) routes in AD model rats to investigate its antiinflammatory and neuroprotective effects. The AD rat model was prepared by bilateral hippocampal injection of amyloid-β (Aβ)_1–42. TGF-β1 was administered via ICV one hour prior to Aβ_1–42 injection or via both nares seven days after Aβ_1–42 injection. ICV administration of TGF-β1 before Aβ_1–42 injection remarkably ameliorated Aβ_1–42-induced neurodegeneration and prevented Aβ_1–42-induced increases in glia-derived proinflammatory mediators (TNF-α, IL-1β and iNOS), as well as T cell-derived proinflammatory cytokines (IFN-γ, IL-2, IL-17 and IL-22), in the hypothalamus, serum or cerebrospinal fluid (CSF) in a concentration-dependent manner. TGF-β1 pretreatment also prevented Aβ_1–42-induced decreases in the neurotrophic factors, IGF-1, GDNF and BDNF, and in the antiinflammatory cytokine, IL-10. Similarly, IN administration of TGF-β1 after Aβ_1–42 injection reduced neurodegeneration, elevation of proinflammatory mediators and cytokines, and reduction of neurotrophic and antiinflammatory factors, in the hypothalamus, serum or CSF. These findings suggest that TGF-β1 suppresses glial and T cell-mediated neuroinflammation and thereby alleviates AD-related neurodegeneration. The effectiveness of IN administered TGF-β1 in reducing Aβ_1–42 neurotoxicity suggests a possible therapeutic approach in patients with AD.

Transforming growth factor beta and soluble endoglin in the healthy senior and in Alzheimer's disease patients

OBJECTIVES

Senescence of the immune system and of endothelial cells can contribute to age-dependent vascular and neurodegenerative disorders including Alzheimer's disease. The aim of this study is an assessment of putative relationships of serum levels of transforming growth factor beta (TGFβ) and soluble endoglin (sCD105) and neurodegeneration, and of changes of these molecules in the course of ageing.

DESIGN

The subjects of the study consisted of three groups, the first one was 63 otherwise healthy middle - aged participants, 31 females, 32 males, of average age 35 years. The second group was formed by 58 healthy, self-dependent inhabitants of nursing homes, 44 females and 14 males, average age 83.5 years. The third group comprised of 129 Alzheimer's disease patients, 86 females, 43 males, of average age 80 years, with MMSE score that ranged from 16 to 20.

MEASUREMENT

Serum levels of TGF beta and soluble endoglin were measured by the ELISA method in samples of peripheral blood using commercial kits.

RESULTS

The serum level of TGFβ was 34,339 ± 6,420 pg/ml in the healthy younger group, 37,555 ± 11,944 pg/ml in the healthy seniors, and 29,057 ± 11,455 pg/ml in Alzheimer's disease patients. Compared to healthy seniors, the serum level of TGFβ was significantly decreased in Alzheimer's disease patients (p < 0.01). The serum level of endoglin were 4.88 ± 0.95 μg/ml in the healthy younger group; 6.11 ± 1.38 μg/ml in healthy seniors, and 7.20 ± 1.72 μg/ml in patients with Alzheimer's disease, respectively. The serum level of endoglin was significantly higher (p < 0.001) in senescent healthy persons compared to the younger control group. When compared with healthy seniors, patients with Alzheimer's disease had significantly elevated (p < 0.001) serum level of endoglin.

CONCLUSIONS

Decreased levels of TGF β in Alzheimer's disease may result in impairment of cerebral circulation reflected in the increased endoglin levels. These findings may indicate involvement of the immune system in Alzheimer's disease pathogenesis.

Bipolar properties of red seabream (Pagrus major) transforming growth factor-beta in induction of the leucocytes migration

TGF-beta is one of the pleiotropic cytokines and plays a pivotal role in immune regulation and orchestrating the subsequent healing response. Recombinant red seabream TGF-beta (rTGF-beta) mature peptide was expressed and purified under native conditions in vitro. Bio-assay showed that the rTGF-beta could significantly induce head kidney (HK) and peripheral blood (PB) leucocytes migration in a dose dependent manner, whereas the rTGF-beta suppressed HK and PB leucocyte migration when the leucocytes was activated by primed with lipopolysaccharide (LPS). Both enhancing and suppressing roles of rTGF-beta on the HKL and PBL chemotactic activity indicated that the fish TGF-beta shared the similar bipolar nature with mammalian TGF-beta. Furthermore, the results indicated that the activity of TGF-beta induction of leucocyte migration appears not to be an innate feature but function by regulation the chemokines activity. This is the first time we reported that fish TGF-beta has innate bipolar property in regulation of fish immune function.

A network analysis of the human T-cell activation gene network identifies JAGGED1 as a therapeutic target for autoimmune diseases

Understanding complex diseases will benefit the recognition of the properties of the gene networks that control biological functions. Here, we set out to model the gene network that controls T-cell activation in humans, which is critical for the development of autoimmune diseases such as Multiple Sclerosis (MS). The network was established on the basis of the quantitative expression from 104 individuals of 20 genes of the immune system, as well as on biological information from the Ingenuity database and Bayesian inference. Of the 31 links (gene interactions) identified in the network, 18 were identified in the Ingenuity database and 13 were new and we validated 7 of 8 interactions experimentally. In the MS patients network, we found an increase in the weight of gene interactions related to Th1 function and a decrease in those related to Treg and Th2 function. Indeed, we found that IFN-ß therapy induces changes in gene interactions related to T cell proliferation and adhesion, although these gene interactions were not restored to levels similar to controls. Finally, we identify JAG1 as a new therapeutic target whose differential behaviour in the MS network was not modified by immunomodulatory therapy. In vitro treatment with a Jagged1 agonist peptide modulated the T-cell activation network in PBMCs from patients with MS. Moreover, treatment of mice with experimental autoimmune encephalomyelitis with the Jagged1 agonist ameliorated the disease course, and modulated Th2, Th1 and Treg function. This study illustrates how network analysis can predict therapeutic targets for immune intervention and identified the immunomodulatory properties of Jagged1 making it a new therapeutic target for MS and other autoimmune diseases.

Transforming growth factor-beta 1 levels in women with prior history of gestational diabetes mellitus

It is known that women with prior history of gestational diabetes mellitus (pGDM) feature obesity, insulin resistance and endothelial dysfunction which cause premature atherosclerosis. Transforming growth factor-beta 1 (TGF-beta1) is a key cytokine in obesity and insulin resistance and also play important roles in the development of atherosclerosis. This study was conducted to demonstrate the serum TGF-beta1 levels of people with pGDM. Thirty women with pGDM, 20 women with type 2 diabetes mellitus (T2DM) and 20 healthy women were enrolled. Serum TGF-beta1 levels of people with pGDM were found to be significantly higher than healthy controls and significantly lower than women with T2DM. TGF-beta1 levels were found to be correlated with postprandial glucose and age and inversely correlated with body mass index (BMI) and waist circumference. On multiple regression analysis postprandial glucose level, age and BMI were determined as the most important factors affecting TGF-beta1 levels. This study demonstrates elevated TGF-beta1 levels in pGDM. The inflammatory response to hyperglycemia and insulin resistance could be the major factors for the increased expression of TGF-beta1.