Cytokine imbalance in non-immunological chronic disease

Use of Local Melatonin with Xenogeneic Bone Graft to Treat Critical-Size Bone Defects in Rats with Osteoporosis: A Randomized Study

The aim of this study was to evaluate the effect of local administration of melatonin (MLT) on molecular biomarkers and calvaria bone critical defects in female rats with or without osteoporosis, associated or not with a xenogeneic biomaterial. Forty-eight female rats were randomly divided into two groups: (O) ovariectomized and (S) placebo groups. After 45 days of osteoporosis induction, two critical-size defects (5 mm diameter) were created on the calvaria. The groups were subdivided according to the following treatment: (C) Clot, MLT, MLT associated with Bio-Oss® (MLTBO), and Bio-Oss® (BO). After 45 days, the defect samples were collected and processed for microtomography, histomorphometry, and biomolecular analysis (Col-I, BMP-2, and OPN). All animals had one femur harvested to confirm the osteoporosis. Microtomography analysis demonstrated a bone mineral density reduction in the O group. Regarding bone healing, the S group presented greater filling of the defects than the O group; however, in the O group, the defects treated with MLT showed higher mineral filling than the other treatments. There was no difference between the treatments performed in the S group (p = 0.05). Otherwise, O-MLT had neoformed bone higher than in the other groups (p = 0.05). The groups that did not receive biomaterial demonstrated lower levels of Col-I secretion; S-MLT and S-MLTBO presented higher levels of OPN, while O-C presented statistically lower results (p < 0.05); O-BO showed greater BMP-2 secretion (p < 0.05). In the presence of ovariectomy-induced osteoporosis, MLT treatment increased the newly formed bone area, regulated the inflammatory response, and increased OPN expression.

A spike in circulating cytokines TNF-α and TGF-β alters barrier function between vascular and musculoskeletal tissues

Molecular transport between the circulatory and musculoskeletal systems regulates articular joint physiology in health and disease. Osteoarthritis (OA) is a degenerative joint disease linked to systemic and local inflammation. Inflammatory events involve cytokines, which are secreted by cells of the immune system and modulate molecular transport across tissue interfaces (referred to as tight junction [TJ] barrier function). In a previous study from our group, OA knee joint tissues were shown to exhibit size separation of different sized molecules delivered as a single bolus to the heart (Ngo et al. in Sci. Rep. 8:10254, 2018). Here, in a follow up study of parallel design, we test the hypothesis that two common cytokines, with multifaceted roles in the etiology of osteoarthritis as well as immune state in general, modulate the barrier function properties of joint tissue interfaces. Specifically, we probe the effect of an acute cytokine increase (spike) on molecular transport within tissues and across tissue interfaces of the circulatory and musculoskeletal systems. A single bolus of fluorescent-tagged 70 kDa dextran, was delivered intracardially, either alone, or with either the pro-inflammatory cytokine TNF-α or the anti-inflammatory cytokine TGF-β, to skeletally mature (11 to 13-month-old) guinea pigs (Dunkin-Hartley, a spontaneous OA animal model). After five minutes' circulation, whole knee joints were serial sectioned and fluorescent block face cryo-imaged at near-single-cell resolution. The 70 kDa fluorescent-tagged tracer is analogous in size to albumin, the most prevalent blood transporter protein, and quantification of tracer fluorescence intensity gave a measure of tracer concentration. Within five minutes, a spike (acute doubling) in circulating cytokines TNF-α or TGF-β significantly disrupted barrier function between the circulatory and musculoskeletal systems, with barrier function essentially abrogated in the TNF-α group. In the entire volume of the joint (including all tissue compartments and the bounding musculature), tracer concentration was significantly decreased in the TGF-β- and TNF-α- compared to the control-group. These studies implicate inflammatory cytokines as gatekeepers for molecular passage within and between tissue compartments of our joints and may open new means to delay the onset and mitigate the progression of degenerative joint diseases such as OA, using pharmaceutical and/or physical measures.

Association of inflammatory and platelet volume markers with clinical outcome in patients with anterior circulation ischaemic stroke after endovascular thrombectomy

Background: To determine the correlation of inflammatory and platelet volume indices with the severity of stroke and 3-month clinical outcomes in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT).Methods: A retrospective analysis was conducted for AIS patients who underwent EVT at our hospital from 2015 to 2019. Inflammatory factors, including white blood count, neutrophil count, lymphocyte count, neutrophil to lymphocyte ratio (NLR), high-sensitivity C-reactive protein (hs-CRP), procalcitonin (PCT) and interleukin-6 (IL-6), and platelet volume indices, including platelet count (PC), mean platelet volume (MPV), platelet distribution width (PDW) and MPV/PC levels were assessed. Results were analyzed between patients with favorable and unfavorable outcomes at 3 months post-EVT.Results: A total of 257 AIS patients were included in the study. There were 86 (33.5%) patients with favorable functional outcomes at 3 months. Compared to patients with favorable outcomes, those with poor outcomes have lower lymphocyte count, higher neutrophil count and NLR levels. There were no differences in hs-CRP,PCT and IL-6 between the two groups. The correlation analysis showed that the increase in MPV, PDW, and MPV/PC was related to the high level of the NIHSS score at admission. Multivariate logistic regression analysis showed that higher NLR levels are an independent risk factor for unfavorable outcomes at 3 months (OR = 1.141; 95% CI 1.061 to 1.227, P = 0.000).Conclusions: MPV, PDW, and MPV/PC are associated with stroke severity. Higher NLR levels upon admission may predict unfavorable functional outcomes in patients with AIS after undergoing EVT.Abbreviations ACA: anterior cerebral artery; AIS: acute ischemic stroke; ASPECTS: alberta stroke program early CT score; BMI: body mass index; DBP: diastolic blood pressure; END: early neurological deterioration; EVT: endovascular thrombectomy; hs-CRP: high-sensitivity C-reactive protein; HT: hemorrhagic transformation; ICA: internal carotid artery; IL-6: interleukin-6; IS: ischemic progression; LAA: Large-Artery Atherosclerosis; MCA: middle cerebral artery; MPV: mean platelet volume; mTICI: modified thrombolysis in cerebral infarction; NIHSS: National Institute of Health stroke scale; NLR: neutrophil to lymphocyte ratio; OTP: onset-to-puncture; PC: platelet count; PCT: procalcitonin; PDW: platelet distribution width; SBP: systolic blood pressure; sICH: symptomatic intracerebral hemorrhageWBC: white blood cell.

Bone mineral density in adolescent urinary stone formers: is sex important?

Urinary stone disease (USD) is affecting a greater number of children and low bone mineral density (BMD) and increased skeletal fractures have been demonstrated in stone patients; however, the mechanism(s) driving bone disease remain unclear. This pilot study was undertaken to assess an adolescent kidney stone cohort's BMD and evaluate for an inverse correlation between BMD and urine concentration of lithogenic minerals and/or inflammatory levels. Prospective case-control study was carried out at a large pediatric center. 15 participants with USD (12-18 years of age, 8 female) were matched by age, sex, and body mass index to 15 controls. Lumbar and total body BMD z-score did not differ between groups. When stone formers were separated by sex, there was a significant difference between male stone formers vs. controls total body BMD z-score (Fig. 1). BMD z-score did not significantly correlate with urine calcium, oxalate, citrate or magnesium. Higher urine IL-13 did significantly correlate with higher total body BMD z-score (r = 0.677, p = 0.018). Total body BMD z-score did significantly correlate with body mass index (BMI) as expected for the control group (r = 0.6321, p = 0.0133). However, this relationship was not present in the USD group (r = - 0.1629, p = 0.5619). This is a small but hypothesis-generating study which demonstrates novel evidence of male-specific low BMD in adolescent stone formers. Furthermore, we demonstrated a positive association between urine IL-13 and total body BMD z-score USD patients as well as a lack of a positive BMD and BMI correlations in stone formers.

The associations of TNF-α gene polymorphisms with bone mineral density and risk of osteoporosis: A meta-analysis

OBJECTIVE

Fracture is a common consequence of osteoporosis and is associated with high morbidity and mortality. Recently, increasing evidence has suggested that polymorphisms in tumor necrosis factor-α (TNF-α) gene were associated with osteoporosis risk and bone mineral density (BMD), but results remain conflicting. We herein performed a meta-analysis based on evidence currently available from the literature to make a more precise estimation of these relationships.

METHODS

The PubMed, EMBASE, Cochrane Library, CNKI (China National Knowledge Infrastructure) and Wan Fang databases were searched for eligible studies. Articles meeting the inclusion criteria were comprehensively reviewed and all available data were accumulated. The pooled odds ratios (ORs) or mean differences (MDs) and corresponding 95% confidence intervals (CIs) were applied to assess the strength of the relationships.

RESULTS

A total of 15 studies involving 5273 subjects were included in our meta-analysis. The GG genotype of TNF-α G308A was associated with an increased risk of osteoporosis under a mutant model (GG vs GA+AA: OR = 0.63, 95% CI: 0.51-0.77, P < 0.0001, I²  = 31%). Additionally, we also observed a significant association between G308A polymorphism and BMD of lumbar spine (AA vs GG: P = 0.01, I²  = 53%). However, TNF-α T1031C, C857T and C863A polymorphisms had no obvious impacts on osteoporosis risk.

CONCLUSIONS

The present meta-analysis demonstrated that TNF-α G308A polymorphism may act as a potential candidate biomarker for screening, diagnosis, and treatment of osteoporosis, which will help improve individualized therapy of osteoporosis patients in clinics.

The Impact of Thyme and Rosemary on Prevention of Osteoporosis in Rats

Osteoporosis poses an important public health problem which affects millions of people worldwide. There is a direct link between calcium deficiency in diet and induction of osteoporosis and bone loss. The current study was conducted to evaluate the protective effect of thyme (Thymus vulgaris L.) and rosemary (Rosmarinus officinalis L.) against osteoporosis in rats with low calcium intake. Essential oils of rosemary and thyme were analyzed. The experiment was carried out on growing male Sprague–Dawley rats; the experimental animals were divided into 5 groups: 1, control negative was fed standard balanced diet; 2, control positive was fed balanced diet with low calcium level (L Ca) (Ca 0.1% w/w); 3, (L Ca) + thyme powder (5% w/w); 4, (L Ca) + rosemary powder (5% w/w); 5, (L Ca) + orally administration with CaCO₃ (27 mg/kg body weight). Blood samples were collected for different biochemical analyses in plasma (calcium (Ca), phosphorus (P), magnesium (Mg), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), malondialdehyde (MDA), parathyroid hormone (PTH), C-terminal telopeptide (CTX), and 1,25-(OH)2-vitamin D3). Femur mass, length, and bone mineral density (BMD) were recorded, and histopathological studies for femurs were examined. Low-calcium diet induced osteoporotic changes in positive control rats (decrease in Ca, vitamin D3, and BMD and increase in CTX, PTH, TNF-α, CRP, and MDA). Supplementation with thyme and rosemary inhibited significantly the development of bone loss, increased Ca and vitamin D3 in plasma, improved BMD, and also prevented the inflammation and oxidative stress (improved TNF-α, CRP and MDA) compared to the positive control. The histopathological examination of treated groups showed an improvement in bone histology and protection against bone loss. However, thyme powder showed more effective impact than rosemary. Our study demonstrates that thyme and rosemary effectively mitigated calcium deficiency-induced bone loss and maybe considered as promising candidates for preventing bone resorption and osteoporosis.

IL-6 Plasma Levels Correlate With Cerebral Perfusion Deficits and Infarct Sizes in Stroke Patients Without Associated Infections

Introduction: We aimed to investigate several blood-based biomarkers related to inflammation, immunity, and stress response in a cohort of patients without stroke-associated infections regarding their predictive abilities for functional outcome and explore whether they correlate with MRI markers, such as infarct size or location. Methods: We combined the clinical and radiological data of patients participating in two observational acute stroke cohorts: the PREDICT and 1000Plus studies. The following blood-based biomarkers were measured in these patients: monocytic HLA-DR, IL-6, IL-8, IL-10, LBP, MRproANP, MRproADM, CTproET, Copeptin, and PCT. Multiparametric stroke MRI was performed including T2^*, DWI, FLAIR, TOF-MRA, and perfusion imaging. Standard descriptive sum statistics were used to describe the sample. Associations were analyzed using Fischer's exact test, independent samples t-test and Spearmans correlation, where appropriate. Results: Demographics and stroke characteristics were as follows: 94 patients without infections, mean age 68 years (SD 10.5), 32.2% of subjects were female, median NIHSS score at admission 3 (IQR 2-5), median mRS 3 months after stroke 1 (IQR 0-2), mean volume of DWI lesion at admission 5.7 ml (SD 12.8), mean FLAIR final infarct volume 10 ml (SD 14.9), cortical affection in 61% of infarctions. Acute DWI lesion volume on admission MRI was moderately correlated to admission/maximum IL-6 as well as maximum LBP. Extent of perfusion deficit and mismatch were moderately correlated to admission/maximum IL-6 levels. Final lesion volume on FLAIR was moderately correlated to admission IL-6 levels. Conclusion: We found IL-6 to be associated with several parameters from acute stroke MRI (acute DWI lesion, perfusion deficit, final infarct size, and affection of cortex) in a cohort of patients not influenced by infections. Clinical Trial Registration: www.ClinicalTrials.gov, identifiers NCT01079728 and NCT00715533.

Inflammation as a contributing factor among postmenopausal Saudi women with osteoporosis

Postmenopausal osteoporosis is an important metabolic bone disease characterized by rapid bone loss occurring in the postmenopausal period. Recently, the most prevalent form of clinically significant osteopenia and osteoporosis involves various inflammatory conditions. The aim of the study is to evaluate the association between proinflammatory markers (interleukin [IL]-1β, IL-6, TNF-α) with bone turnover markers (BTMs) in postmenopausal Saudi women with and without osteoporosis. A total of 200 postmenopausal Saudi women ≥50 years old, 100 with osteoporosis and 100 without osteoporosis (control) were recruited under the supervision of qualified physicians in King Salman Hospital and King Fahd Medical City, Riyadh, Saudi Arabia. Serum tumor necrosis factor alpha (TNF-α), IL-1, IL-4, IL-6, and parathyroid hormone (PTH) were determined using Luminex xMAP technology. N-telopeptides of collagen type I (NTx) was assessed using ELISA, 25(OH) vitamin D and osteocalcin were determined using electrochemiluminescence, serum calcium and inorganic phosphate (Pi) were measured by a chemical analyzer. Serum IL-1β, IL-6, NTx, and PTH levels in women with osteoporosis were significantly higher than controls. Although IL-4 and osteocalcin were significantly lower than controls. IL-1β and TNF-α were positively associated with NTx in osteoporosis women. TNF-α, IL-6, and TNF-α were positively correlated with IL-lβ in both groups. A significant negative correlation between osteocalcin and IL-1β in healthy women and women with osteoporosis were observed. Findings of the present study implicate a role for cytokine pattern-mediated inflammation in patients with osteoporosis.

Regulation of type 2 diabetes by helminth-induced Th2 immune response

Helminth-induced type 2 cytokines increase the number of regulatory T cells and alternatively activated macrophages, resulting in modulation of the host–immune system. Studies on these parasite-induced immunoregulatory mechanisms might contribute to the development of new therapies for inflammatory diseases, including type 2 diabetes (T2D). Previous studies have suggested that progression of obesity-associated metabolic abnormalities is under pathophysiological control of CD4+ T cells. Glucose absorption through the intestinal epithelium reduced after infection in a STAT-6-dependent manner. In this study, we investigated whether infection with the gastrointestinal nematode parasite Heligmosomoides polygyrus (Hp) can modulate T2D-associated pathology in a mouse model (KK-Ay/TaJcl). KK-Ay/TaJcl mice were inoculated with infective third-stage Hp larvae and studied at Day 8 following infection. Uninfected KK-Ay/TaJcl mice showed high blood glucose levels even 120 min after administration of glucose by IP injection. However, it was significantly improved in the infected group. HOMA-IR, fat accumulation and FAS gene expression in the liver were significantly decreased by Hp infection. GLUT2 gene expression in this group was significantly lower than that in the uninfected diabetic mice, which might be related to the decrease in glucose absorption in the parasite-infected intestine. In conclusion, helminth-induced type 2 immune responses might contribute to T2D disease control.

Serum carcinoembryonic antigen-related cell adhesion molecule 1 level in postmenopausal women: correlation with β-catenin and bone mineral density

Many epidemiological studies have shown that in some tumors carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and β-catenin appear to be related. However, it remains to be established whether CEACAM1 is related to β-catenin in osteoporosis. Here, we reveal that CEACAM1 might influence the canonical Wnt/β-catenin pathway to modulate bone metabolism in postmenopausal osteoporosis.

INTRODUCTION

The aim of this study is to assess the serum level of CEACAM1 in postmenopausal women and its correlation with β-catenin and bone mineral density (BMD).

METHODS

The BMD was measured at the lumbar spine (L1-L4) or the femoral neck using dual-energy X-ray absorptiometry (DXA). Serum CEACAM1, β-catenin, receptor activator of nuclear factor kappa-B (RANKL), osteoprotegerin (OPG), β-isomerized C-terminal crosslinking of type I collagen (β-CTX), intact N-terminal propeptide of type I collagen (PINP), estradiol, and insulin were measured in 350 postmenopausal women. Patients were divided according to lumbar spine or femur neck T-scores into osteoporosis (group I), osteopenia (group II), and normal bone mineral density, the latter serving as control.

RESULTS

Serum CEACAM1 levels were significantly lower in group I and II compared to those in control subjects (P < 0.001). Serum CEACAM1 levels correlated positively with β-catenin and BMD, but correlated negatively to the ratio between RANKL and OPG.

CONCLUSION

This study provides evidence that decreased serum CEACAM1 levels are related to low BMD in postmenopausal women, and that serum CEACAM1 levels correlated positively to β-catenin. It suggests that CEACAM1 might influence the canonical Wnt/β-catenin pathway to modulate bone metabolism.

Ebselen Is a Potential Anti-Osteoporosis Agent by Suppressing Receptor Activator of Nuclear Factor Kappa-B Ligand-Induced Osteoclast Differentiation In vitro and Lipopolysaccharide-Induced Inflammatory Bone Destruction In vivo

Ebselen is a non-toxic seleno-organic drug with anti-inflammatory and antioxidant properties that is currently being examined in clinical trials to prevent and treat various diseases, including atherosclerosis, stroke, and cancer. However, no reports are available for verifying the pharmacological effects of ebselen on major metabolic bone diseases such as osteoporosis. In this study, we observed that ebselen suppressed the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells in an osteoblast/osteoclast co-culture by regulating the ratio of receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin secreted by osteoblasts. In addition, ebselen treatment in the early stage of osteoclast differentiation inhibited RANKL-dependent osteoclastogenesis by decreasing the phosphorylation of IκB, PI3K, and Akt in early signaling pathways and by subsequently inducing c-Fos and nuclear factor of activated T-cells c1. Further, ebselen induced apoptosis of osteoclasts in the late stage of osteoclast differentiation. In addition, ebselen treatment suppressed filamentous actin ring formation and bone resorption activity of mature osteoclasts. Reflecting these in vitro effects, administration of ebselen recovered bone loss and its µ-CT parameters in lipopolysaccharide-mediated mouse model. Histological analysis confirmed that ebselen prevented trabecular bone matrix degradation and osteoclast formation in the bone tissues. Finally, it was proved that the anti-osteoclastogenic action of ebselen is achieved through targeting N-methyl-D-aspartate (NMDA) receptor. These results indicate that ebselen is a potentially safe drug for treating metabolic bone diseases such as osteoporosis.

Longitudinal analysis of immune abnormalities in varying severities of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis patients

Background

Research has identified immunological abnormalities in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), a heterogeneous illness with an unknown cause and absence of diagnostic test. There have been no CFS/ME studies examining innate and adaptive immune cells longitudinally in patients with varying severities. This is the first study to investigate immune cells over 6 months while also examining CFS/ME patients of varying symptom severity.

Methods

Participants were grouped into 18 healthy controls, 12 moderate and 12 severe CFS/ME patients and flow cytometry was used to examine cell parameters at 0 and 6 months.

Results

Over time, iNKT CD62L expression significantly increased in moderate CFS/ME patients and CD56^bright NK receptors differed in severe CFS/ME. Naïve CD8⁺T cells, CD8⁻CD4⁻ and CD56⁻CD16⁻ iNKT phenotypes, γδ2T cells and effector memory subsets were significantly increased in severe CFS/ME patients at 6 months. Severe CFS/ME patients were significantly reduced in CD56^brightCD16^dim NKG2D, CD56^dimCD16⁻ KIR2DL2/DL3, CD94⁻CD11a⁻ γδ1T cells and CD62L⁺CD11a⁻ γδ1T cells at 6 months.

Conclusions

Severe CFS/ME patients differed from controls and moderate CFS/ME patients over time and expressed significant alterations in iNKT cell phenotypes, CD8⁺T cell markers, NK cell receptors and γδT cells at 6 months. This highlights the importance of further assessing these potential immune biomarkers longitudinally in both moderate and severe CFS/ME patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0653-3) contains supplementary material, which is available to authorized users.

Association of bone loss with the upregulation of survival-related genes and concomitant downregulation of Mammalian target of rapamycin and osteoblast differentiation-related genes in the peripheral blood of late postmenopausal osteoporotic women

We aimed to identify bone related markers in the peripheral blood of osteoporotic (OP) patients that pointed toward molecular mechanisms underlying late postmenopausal bone loss. Whole blood from 22 late postmenopausal OP patients and 26 healthy subjects was examined. Bone mineral density (BMD) was measured by DXA. Protein levels of p70-S6K, p21, MMP-9, TGFβ1, and caspase-3 were quantified by ELISA. Gene expression was measured using real-time RT-PCR. OP registered by low BMD indices in late postmenopausal patients was associated with a significant upregulation of autophagy protein ULK1, cyclin-dependent kinase inhibitor p21, and metalloproteinase MMP-9 gene expression in the blood compared to the healthy controls and in a significant downregulation of mTOR (mammalian target of rapamycin), RUNX2, and ALPL gene expression, while expression of cathepsin K, caspase-3, transforming growth factor (TGF) β1, interleukin- (IL-) 1β, and tumor necrosis factor α (TNFα) was not significantly affected. We also observed a positive correlation between TGFβ1 and RUNX2 expression and BMD at femoral sites in these patients. Therefore, bone loss in late postmenopausal OP patients is associated with a significant upregulation of survival-related genes (ULK1 and p21) and MMP-9, as well as the downregulation of mTOR and osteoblast differentiation-related genes (RUNX2 and ALPL) in the peripheral blood compared to the healthy controls.

Bone resorption correlates with the frequency of CD5⁺ B cells in the blood of patients with rheumatoid arthritis

OBJECTIVE

The prevention of bone resorption and subsequent joint destruction is one of the main challenges in the treatment of patients suffering from RA. Various mechanisms have previously been described that contribute to bone resorption in tightly defined cohorts. Here we analysed a cross-sectional cohort of RA patients and searched for humoral and cellular markers in the peripheral blood associated with bone resorption.

METHODS

We enrolled 61 consecutive RA patients positive for ACPA. Blood was analysed by flow cytometry to determine the percentages of regulatory T cells and B cell subpopulations. Cytokine (TNF-α, IL-6, IL-10) and ACPA levels as well as the bone resorption marker CTX-1 were determined from the patients' sera. Standard clinical disease parameters were included.

RESULTS

Multivariate analyses showed that the percentages of CD5(+) B cells were positively correlated with CTX-1 serum levels. However, neither low-avidity ACPA nor serum IL-6 levels, both known to be produced by CD5(+) cells, were associated with CTX-1 in patients' sera. There was no correlation between CTX-1 levels and clinical parameters or ACPA levels.

CONCLUSION

In summary, we found that the CD5(+) B cell population is associated with bone resorption as measured via serum CTX-1 levels in a cross-sectional cohort of RA patients. However, a possible functional link between CD5(+) B cells and bone resorption still needs to be defined.

Prognostic value of blood interleukin-6 in the prediction of functional outcome after stroke: a systematic review and meta-analysis

We aimed to quantify the association of blood interleukin-6 (IL-6) concentrations with poor outcome after stroke and its added predictive value over clinical information. Meta-analysis of 24 studies confirmed this association with a weighted mean difference of 3.443 (1.592-5.294) pg/mL, despite high heterogeneity and publication bias. Individual participant data including 4112 stroke patients showed standardized IL-6 levels in the 4th quartile were independently associated with poor outcome (OR=2.346 (1.814-3.033), p<0.0001). However, the additional predictive value of IL-6 was moderate (IDI=1.5%, NRI=5.35%). Overall these results indicate an unlikely translation of IL-6 into clinical practice for this purpose.

Short-term caloric restriction does not reduce bone mineral density in rats with early type 2 diabetes

BACKGROUND

The effect of caloric restriction (CR) in the setting of diabetes on bone metabolism has not yet been fully studied. The aim of this study is to determine if short-term CR alters bone mass and metabolism in Otsuka Long-Evans Tokushima fatty (OLETF) rats, an animal model of type 2 diabetes.

METHODS

Four groups (n=5) were created: OLETF rats with food ad libitum (AL), OLETF rats with CR, Long-Evans Tokusima Otsuka (LETO) rats with food AL, and LETO rats with CR. The CR condition was imposed on 24-week-old male rats using a 40% calorie reduction for 4 weeks. The effect of CR on femoral bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry. Serum markers were measured by immunoassay.

RESULTS

After 4 weeks of CR, body weight decreased in both strains. The BMD decreased in LETO rats and was maintained in OLETF rats. After adjustment for body weight, BMD remained lower in LETO rats (P=0.017) but not OLETF rats (P=0.410). Bone-specific alkaline phosphatase levels decreased in LETO rats (P=0.025) but not in OLEFT rats (P=0.347). Serum leptin levels were reduced after CR in both strains, but hyperleptinemia remained in OLETF rats (P=0.009). CR increased 25-hydroxyvitamin D levels in OLETF rats (P=0.009) but not in LETO rats (P=0.117). Additionally, interleukin-6 and tumor necrosis factor-α levels decreased only in OLETF rats (P=0.009).

CONCLUSION

Short-term CR and related weight loss were associated with decreases of femoral BMD in LETO rats while BMD was maintained in OLETF rats. Short-term CR may not alter bone mass and metabolism in type 2 diabetic rats.

T cell replicative senescence in human aging

The decline of the immune system appears to be an intractable consequence of aging, leading to increased susceptibility to infections, reduced effectiveness of vaccination and higher incidences of many diseases including osteoporosis and cancer in the elderly. These outcomes can be attributed, at least in part, to a phenomenon known as T cell replicative senescence, a terminal state characterized by dysregulated immune function, loss of the CD28 costimulatory molecule, shortened telomeres and elevated production of proinflammatory cytokines. Senescent CD8 T cells, which accumulate in the elderly, have been shown to frequently bear antigen specificity against cytomegalovirus (CMV), suggesting that this common and persistent infection may drive immune senescence and result in functional and phenotypic changes to the T cell repertoire. Senescent T cells have also been identified in patients with certain cancers, autoimmune diseases and chronic infections, such as HIV. This review discusses the in vivo and in vitro evidence for the contribution of CD8 T cell replicative senescence to a plethora of age-related pathologies and a few possible therapeutic avenues to delay or prevent this differentiative end-state in T cells. The age-associated remodeling of the immune system, through accumulation of senescent T cells has farreaching consequences on the individual and society alike, for the current healthcare system needs to meet the urgent demands of the increasing proportions of the elderly in the US and abroad.

Association between peripheral T-Lymphocyte activation and impaired bone mineral density in HIV-infected patients

Background

HIV-infected patients display an increased and early incidence of osteopenia/osteoporosis. We investigated whether bone metabolism disorders in HIV-infected patients are related to immune hyperactivation and premature immune senescence.

Methods

Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA): low BMD (LBMD) was defined as T-score or z-score < -1. CD4+/CD8+ phenotype (CD38/HLA-DR, CD127, CD28/CD57), and circulating IL-7, TNF-α, RANKL, OPG were measured. The variables with p < .05 were evaluated by multivariate logistic regression.

Results

78 patients were enrolled: 55 were LBMD. LBMD patients showed increased activated HDLADR + CD4+ and CD8+ (p = .03 and p = .002, respectively). Interestingly, no differences in senescent CD28-CD57 + CD4+/CD8+ T-cells were observed between groups. However, LBMD patients displayed a decreased CD4 + CD28- phenotype (p = .04) at the advantage of the CD28+ pool (p = .03), possibly reflecting heightened apoptosis of highly differentiated CD28-negative cells.

Activated HLADR + CD4+/CD8+ and CD28 + CD4+ cells were independently associated with impaired BMD (AOR = 1.08 for each additional HLADR + CD4+ percentage higher; CI 95%,1.01-1.15; p = .02; AOR = 1.07 for each additional HLADR + CD8+ percentage higher; CI 95%,1.01-1.11; p = .01; AOR = 1.06 for each additional CD28 + CD4+ percentage higher; CI 95%,1.0-1.13; p = .05).

Conclusions

Heightened T-cell activation in HIV-infected patients independently predicts BMD disorders, suggesting a critical role of immune activation in the pathogenesis of osteopenia/osteoporosis, even in patients achieving full viral suppression with HAART.

Electronic supplementary material

The online version of this article (doi:10.1186/1479-5876-11-51) contains supplementary material, which is available to authorized users.

T cell replicative senescence in human aging

The decline of the immune system appears to be an intractable consequence of aging, leading to increased susceptibility to infections, reduced effectiveness of vaccination and higher incidences of many diseases including osteoporosis and cancer in the elderly. These outcomes can be attributed, at least in part, to a phenomenon known as T cell replicative senescence, a terminal state characterized by dysregulated immune function, loss of the CD28 costimulatory molecule, shortened telomeres and elevated production of proinflammatory cytokines. Senescent CD8 T cells, which accumulate in the elderly, have been shown to frequently bear antigen specificity against cytomegalovirus (CMV), suggesting that this common and persistent infection may drive immune senescence and result in functional and phenotypic changes to the T cell repertoire. Senescent T cells have also been identified in patients with certain cancers, autoimmune diseases and chronic infections, such as HIV. This review discusses the in vivo and in vitro evidence for the contribution of CD8 T cell replicative senescence to a plethora of age-related pathologies and a few possible therapeutic avenues to delay or prevent this differentiative end-state in T cells. The age-associated remodeling of the immune system, through accumulation of senescent T cells has farreaching consequences on the individual and society alike, for the current healthcare system needs to meet the urgent demands of the increasing proportions of the elderly in the US and abroad.

Low-grade systemic inflammation and suboptimal bone mineral density throughout adolescence: a prospective study in girls

OBJECTIVE

We aimed at quantifying the associations between high-sensitivity C-reactive protein (hs-CRP) and forearm bone mineral density (BMD) throughout adolescence in overweight and normal-weight girls.

DESIGN

Prospective cohort study.

PATIENTS

346 girls born in 1990 and attending schools in Porto, Portugal.

MEASUREMENTS

Adolescents were evaluated at 13 and 17 years of age using a standard protocol. Forearm BMD was measured by dual-energy X-ray absorptiometry. Anthropometric assessment included weight, height, body fat percentage and waist circumference. Girls were categorized according to age- and sex-specific body mass index (BMI) percentiles as normal weight in both evaluations or overweight in at least one assessment. Pubertal development was estimated using menarche age. Serum hs-CRP was determined using particle-enhanced immunonephelometry. Hs-CRP was log-transformed, and associations were quantified using linear regression coefficients and 95% confidence intervals (95%CI).

RESULTS

An inverse association between hs-CRP and BMD was observed from 13 years of age in overweight girls [-11·26 mg/cm(2) (-21·99, -0·52)]. Among normal-weight adolescents, 13-year-old hs-CRP was negatively associated with prospective BMD variation between 13 and 17 years of age [-1·90 mg/cm(2) year (-3·35, -0·45)]. Overweight girls who maintained higher levels of hs-CRP throughout adolescence had lower 17-year-old BMD (adjusted mean 0·441 vs 0·483 g/cm(2) in those who remained with lower levels of hs-CRP). At 17 years of age, significant inverse associations were found between hs-CRP and BMD among normal-weight and overweight girls.

CONCLUSIONS

Obesity-related early systemic inflammation might be involved in suboptimal bone accrual, particularly in overweight girls.

Long-term aerobic exercise and omega-3 supplementation modulate osteoporosis through inflammatory mechanisms in post-menopausal women: a randomized, repeated measures study

BACKGROUND

Evidence indicates that dietary fats and physical activity influence bone health. The purpose of this study was to examine the effects of long-term aerobic exercise and omega-3 (N-3) supplementation on serum inflammatory markers, bone mineral density (BMD), and bone biomarkers in post-menopausal women.

METHODS

Seventy-nine healthy sedentary post-menopausal women aged 58-78 years participated in this study. Subjects were randomized to one of 4 groups: exercise + supplement (E+S, n = 21), exercise (E, n = 20), supplement (S, n = 20), and control (Con, n = 18) groups. The subjects in the E+S and E groups performed aerobic exercise training (walking and jogging) up to 65% of HRmax, three times a week for 24 weeks. Subjects in the E+S and S groups consumed 1000 mg/d N-3 for 24 weeks. The lumbar spine (L2-L4) and femoral neck BMD, serum tumor necrosis factor (TNF) α, interleukin (IL) 6, prostaglandin (PG) E2, estrogen, osteocalcin, 1, 25-dihydroxyvitamin D3 (1, 25 Vit D), C-telopeptide (CTX), parathyroid hormone (PTH) and calcitonin (CT) were measured at baseline, the end of week 12 and 24.

RESULTS

Serum estrogen, osteocalcin, 1, 25 Vit D, CT, L2-L4 and femoral neck BMD measures increased (P < 0.05) and the serum CTX, PTH, TNF-α, IL-6, and PGE2 decreased (P < 0.05) in E + S group after the 24 wk intervention but not in the E or S intervention groups. L2-L4 and femoral neck BMD, estrogen, osteocalcin, and CT were negatively (P < 0.05) correlated with TNF-α and PGE2. PTH and CT were correlated positively and negatively with IL-6, respectively (P < 0.05).

CONCLUSIONS

The present study demonstrates that long-term aerobic exercise training plus N-3 supplementation have a synergistic effect in attenuating inflammation and augmenting BMD in post-menopausal osteoporosis.

Relationship between vitamin K status, bone mineral density, and hs-CRP in young Korean women

Vitamin K intake has been reported as an essential factor for bone formation. The current study was conducted under the hypothesis that insufficient vitamin K intake would affect inflammatory markers and bone mineral density in young adult women. The study was a cross-sectional design that included 75 women in their 20s. Physical assessments, bone mineral density measurements, 24-hr dietary recalls, and biochemical assessments for high sensitivity C-reactive protein (hs-CRP) and percentages of undercarboxylated osteocalcin (%ucOC) were performed. An analysis of vitamin K nutritional status was performed comparing first, second, and third tertiles of intake based on %ucOC in plasma. Vitamin K intake levels in the first, second, and third tertiles were 94.88 ± 51.48 µg, 73.85 ± 45.15 µg, and 62.58 ± 39.92 µg, respectively (P < 0.05). The T-scores of the first and third tertiles were 1.06 and -0.03, respectively, indicating that bone mineral density was significantly lower in the group with lower vitamin K intake (P < 0.05). There was a tendency for different serum hs-CRP concentrations between the first (0.04 ± 0.02) and third tertiles (0.11 ± 0.18), however this was not statistically significant. Regression analysis was performed to identify the correlations between vitamin K nutritional status, inflammatory markers, and bone mineral density after adjusting for age and BMI. Serum hs-CRP concentrations were positively correlated with vitamin K deficiency status (P < 0.05). And bone mineral density, which was represented by speed, was negatively correlated with vitamin K deficiency status (P < 0.05). In conclusion, status of vitamin K affects inflammatory status and bone formation. Therefore, sufficient intake of vitamin K is required to secure peak bone mass in young adult women.

Relationship between the serum CA-125 level and bone mineral density in healthy pre- and post-menopausal women

BACKGROUND

Osteoporosis and tumour-associated antigen (TAA) levels are associated with inflammatory processes, but little remains known about TAA levels and bone mineral density (BMD).

AIMS

We determined whether or not high-normal TAA levels are associated with a lower BMD in healthy women.

METHODS

A total of 3769 healthy women were enrolled from the health screening programme over 5 years. Each participant had undergone a basic health examination. Serum carbohydrate antigen (CA)-125, CA-19-9, carcinoembryonic antigen (CEA) and alpha-fetoprotein levels were evaluated as tumour markers. The correlations between serum TAA levels and BMD were analysed.

RESULTS

Carbohydrate antigen 125 and CEA levels were positively associated with a higher BMD in the pre-menopause. In the post-menopause, the CA-125 level was positively associated with BMD. In the pre-menopause, CA-125 (r = 0.102; P < 0.001) and CEA levels (r = 0.134; P < 0.001) had a significant correlation with BMD. In the post-menopause, CA-125 was negatively associated with alkaline phosphatase (r = -0.298; P < 0.001).

CONCLUSIONS

There was a significant positive association between CA-125 and BMD in healthy women. Additional basic and clinical studies on the relationship between CA-125 and bone are needed.

Bone mineral density in patients with familial Mediterranean fever

This study was carried out to determine lumbar and femoral bone mineral density (BMD) in patients with familial Mediterranean fever (FMF), an autosomal-recessive disease characterized by recurrent episodes of peritonitis, pleuritis, and arthritis, which are usually associated with fever. In patients with FMF and control subjects, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured. BMD was determined at the lumbar spine (L1-4) and the femoral regions (neck and total) using dual energy X-ray absorptiometry. Twenty-eight FMF patients and 30 control subjects without a history of inflammatory disease participated in our study. The demographic variables, such as age, sex and body mass index were similar between patients and controls (P > 0.05). We found statistically significant difference in ESR and CRP between FMF patients and controls (P < 0.01, P < 0.05 respectively). There was statistically significant difference in lumbar spine, femoral neck, and total femur BMD between FMF patients and control groups (P < 0.001, P < 0.01, P < 0.01 respectively).Our study indicates that lumbar spine and femoral neck and total femur BMD in patients with FMF may be lower than in healthy subjects.

[Pathogenesis of osteoarthritis--a snapshot]

Osteoarthritis (OA) is a degenerative joint disease of as yet unknown pathology. Combining genome and transcriptome analyses with methods from systems biology helped to identify OA as the result of active disease processes. Here, chondrocytes are of central importance as they seem to undergo increased apoptosis and to shift their metabolism towards cartilage degradation.

Elevated IL-6 levels in the synovial fluid of osteoarthritis patients stem from plasma cells

OBJECTIVE

To analyse the levels of interleukin-6 (IL-6) in the synovial fluids and sera of patients with osteoarthritis (OA) and to identify the IL-6-secreting cells.

METHODS

Serum, synovial fluid, synovial tissue, and articular cartilage samples were collected from 49 OA patients with end-stage knee or hip OA who underwent joint replacement surgery. Serum and synovial fluid levels of IL-6 were measured by enzyme-linked immunosorbent assay (ELISA) and IL-6-secreting cells were identified by immunohistochemistry.

RESULTS

Eight out of 49 patients (16%) exhibited elevated IL-6 levels in the synovial fluids, averaging at 2022+/-526 pg/mL, while the levels in the rest of the patients averaged at 132+/-19 pg/mL. The sera levels of all patients were comparable in the 10 pg/mL range. Immunohistochemical analyses revealed plasma cells in the synovial lining of the high producers as the source of IL-6.

CONCLUSIONS

Synovial fluid IL-6 levels may help to classify OA patients and may point to a subgroup with a particular impact from their immune system.

Bone mineral density and bone turnover markers of patients with Behçet's disease

BACKGROUND

Behçet's disease (BD) is a systemic inflammatory disease of unknown aetiology. The pathogenesis of rheumatological findings and the status of bone metabolism in this disease are unknown. Inflammatory diseases may predispose to a decrease in bone mineral density (BMD) and there are many studies concerning osteoporosis in chronic inflammatory diseases.

OBJECTIVE

The aim of this study was to investigate BMD and bone turnover markers in patients with BD.

METHODS

Thirty BD patients (17 male and 13 female patients, mean age 36.9+/-12.6 years) and a total of 30 age- and sex-matched healthy controls (17 male and 13 female controls, mean age 34.9+/-8.95 years) recruited from the general population were enrolled in the study. Bone mineral density was measured at the lumbar spine (L1-4) and the left hip (total hip) using dual energy X-ray absorptiometry. Serum samples were collected between 8 and 10 am after overnight fasting. Serum calcium (Ca), phosphate (P), parathormone (PTH), total alkaline phosphatase (ALP), osteocalcin (OC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were measured. Free deoxypyridinoline cross-links (DPD) in second-void urine and total daily urinary calcium excretion were analysed.

RESULTS

No statistically significant difference in lumbar spine or femoral BMD and bone turnover markers were found between BD patients and control groups (P>0.05).

CONCLUSION

Although it is difficult to draw definite conclusions because of the limited number of patients involved, our study indicates that bone mineral density and bone turnover markers in Behçet's disease were no different than in healthy subjects.

Inflammatory biomarkers in blood of patients with acute brain ischemia

Although many failed surrogate markers are provided in the literature, inflammation may contribute to the outcome of ischemic stroke. In 50 consecutive patients with acute ischemic stroke, in the absence of symptoms and signs of concomitant infection, we evaluated a panel of biomarkers reported to be variably associated with brain ischemia, and correlate their serum level with the brain lesion volume and clinical outcome. Infarct size was calculated on computed tomography (CT) scans by means of the Cavalieri's method. Neurological impairment was scored by using the Glasgow Coma Scale, Glasgow Outcome Scale and National Institutes of Health (NIH) scales at stroke onset and 3-month follow-up. Some markers showed a direct significant correlation with both initial and final NIH scale and with infarct size, particularly tumor necrosis factor alpha (TNF-alpha) (P=0.002), intercellular adhesion molecule-1 (P<0.01) and matrix metalloproteinase-2/9 (P=0.001). In contrast to previous reports, interleukin-6 (IL-6) serum level showed a significant inverse correlation with both final neurological impairment and infarct size (P<0.001). This novel finding allows us suggesting that IL-6, in the context of a complex pro-inflammatory network occurring during stroke, is associated with neuroprotection rather than neurotoxicity in patients with ischemic brain injury.

Cis- and trans-acting gene regulation is associated with osteoarthritis

Osteoarthritis (OA) is a complex disease of the skeleton and is associated with aging. Both environmental and genetic factors contribute to its pathogenesis. We set out to identify novel genes associated with OA, concentrating on regulatory polymorphisms allowing for differential expression. Our strategy to identify differentially expressed genes included an initial transcriptome analysis of the peripheral blood mononuclear cells of six patients with OA and six age-matched healthy controls. These were screened for allelic expression imbalances and potentially regulatory single-nucleotide polymorphisms (SNPs) in the 5' regions of the genes. To establish disease association, disparate promoter SNP distributions correlating with the differential expression were tested on larger cohorts. Our approach yielded 26 candidate genes differentially expressed between patients and controls. Whereas BLP2 and CIAS1 seem to be trans-regulated, as the absence of allelic expression imbalances suggests, the presence of allelic imbalances confirms cis-regulatory mechanisms for RHOB and TXNDC3. Interestingly, on/off-switching suggests additional trans-regulation for TXNDC3. Moreover, we demonstrate for RHOB and TXNDC3 statistically significant associations between 5' SNPs and the disease that hint at regulatory functions. Investigating the respective genes functionally will not only shed light on the disease association but will also add to the understanding of the pathogenic processes involved in OA and may point out novel therapeutic approaches.

Osteoporosis, inflammation and ageing

Osteoporosis is a condition characterized by low bone mass and increased bone fragility, putting patients at risk of fractures, which are major causes of morbidity substantially in older people. Osteoporosis is currently attributed to various endocrine, metabolic and mechanical factors. However, emerging clinical and molecular evidence suggests that inflammation also exerts significant influence on bone turnover, inducing osteoporosis. Numerous proinflammatory cytokines have been implicated in the regulation of osteoblasts and osteoclasts, and a shift towards an activated immune profile has been hypothesized as important risk factor. Chronic inflammation and the immune system remodelling characteristic of ageing, as well as of other pathological conditions commonly associated with osteoporosis, may be determinant pathogenetic factors. The present article will review the current perspectives on the interaction between bone and immune system in the elderly, providing an interpretation of osteoporosis in the light of inflamm-ageing.

Higher circulating hsCRP levels are associated with lower bone mineral density in healthy pre- and postmenopausal women: evidence for a link between systemic inflammation and osteoporosis

Factors involved in inflammation are linked with those critical for bone remodeling. We examined the association between serum high sensitivity C-reactive protein (hsCRP) levels and bone mineral density (BMD) in healthy women. Serum concentrations of hsCRP and total alkaline phosphatase (ALP) were measured in premenopausal ( n =3,662) and postmenopausal ( n =1,031) women aged 30 years or older. BMD was measured at the femoral neck and lumbar spine using dual energy X-ray absorptiometry. According to the WHO definition, osteopenia was diagnosed at -2.5< T -score < -1.0 SD, and osteoporosis was diagnosed at T -score < or = -2.5 SD at any sites. Compared with normal subjects, log-transformed serum hsCRP levels were higher in osteopenic and osteoporotic subjects (all, P < 0.001) with linearity ( P for trend <0.001), after adjustment for age, BMI and menopausal status. Menopausal status did not have a significant interaction on the association ( P =0.457). In both premenopausal and postmenopausal women, serum total ALP levels were higher in the subjects with higher hsCRP quintiles than those with the lowest quintile (all, P for trend < 0.001). Multivariate-adjusted odds ratio (OR) for osteoporosis and osteopenia were 1.35 (95% CI, 1.08 to 1.68) in the highest hsCRP quintile of premenopausal women, and OR for osteoporosis was 1.54 (95% CI, 1.10 to 2.53) in the highest hsCRP quintile of postmenopausal women. These findings suggest that subclinical systemic inflammation may be associated with bone turnover rate and bone mass in healthy women.

Association of the OSCAR promoter polymorphism with BMD in postmenopausal women

In an effort to identify genetic polymorphisms in potential candidate genes for osteoporosis, 10 variants were identified in the OSCAR gene using direct DNA sequencing, and 560 postmenopausal women were genotyped at five SNP loci, using the TaqMan method. The rare allele (G allele) of OSCAR-2322A>G (SNP in the 5' flanking region) showed significant association with lower BMD at various bone sites in postmenopausal women (n = 560).

INTRODUCTION

BMD is the major factor for determining bone strength and osteoporotic fracture risk and is determined by both environmental and multiple genetic factors. The osteoclast-associated receptor (OSCAR) plays a critical role in osteoclast differentiation and thus is an important candidate gene for the modulation of BMD.

MATERIALS AND METHODS

Through direct sequencing in 24 Korean individuals, 10 sequence variants were identified: 2 in the 5' flanking region, 7 in the exons (including 6 nonsynonymous single-nucleotide polymorphisms [SNPs]), and 1 in an intron. Five of these polymorphisms were selected for larger-scale genotyping in postmenopausal women (n = 560). Areal BMD (g/cm2) of the anterior-posterior lumbar spine and the nondominant proximal femur was measured using DXA (Lunar Expert XL and Hologic QDR 4500-A). Lateral thoracolumbar radiographs were obtained in all subjects.

RESULTS

Using multiple regression analysis and controlling for age, years since menopause, height, weight, and evaluation machine as covariates, the rare allele (G allele) of OSCAR-2322A>G showed significant association with lower BMD at various bone sites in postmenopausal women.

CONCLUSION

These findings suggest that the promoter variant in OSCAR gene (OSCAR-2322A>G) might be one of genetic determinants of BMD in postmenopausal women.

Genetics and genotypes in irritable bowel syndrome: implications for diagnosis and treatment

Several twin studies and familial aggregation studies in IBS are consistent with either a genetic or a social learning hypothesis, and it is possible that both play a role. The prospect of identifying a genetic cause for IBS may be very important, because it raises the possibility of confirming that IBS isa disease entity, suggests new insight into the pathophysiology of the disorder, and provides new targets for drug development. Several candidate genetic markers including: those related to cytokines such as IL-10, TNF-alpha and TGF beta1; SERT-P; alpha-adrenergic receptors; and G proteins have been associated with certain aspects of IBS. Genetic polymorphisms,however, are common and may have no etiological or pathogenetic relevance. Searching for the genes in IBS is of potentially great relevance. Such studies may identify more specific phenotypes in IBS or potentially predict increased disease vulnerability, but it is unlikely that this strategy will lead to a diagnostic test, given the limited component of IBS that is likely to be genetically determined. Pharmaco genomic studies have potential to be important in the future. For this potential to be realized, it will be necessary to formally include genetic studies in trials of experimental drugs.This would enhance understanding of one of the roles of genetics for treating IBS.

TRAIL in the airways

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is an important immunomodulatory factor that may play a role in the structural changes observed in the asthmatic airways. In vitro as well as in vivo studies have evidenced a dual role for TRAIL: it can either function as a pro- or anti-inflammatory cytokine on inflammatory cells, participating in the initiation and resolution of inflammatory and immune responses. TRAIL is expressed in the airways by inflammatory cells infiltrated in the bronchial mucosa, as well as by structural cells of the airway wall including fibroblasts, epithelial, endothelial, and smooth muscle cells. By releasing TRAIL, these different cell types may then participate in the increased levels of TRAIL observed in bronchoalveolar lavage fluid from asthmatic patients. Taken together, this suggests that TRAIL may play a role in inflammation in asthma. However, concerning its role is dual in the modulation of inflammation, further studies are needed to elucidate the precise role of TRAIL in the airways.

Prenatal exposure to IL-1beta results in disturbed skeletal growth in adult rat offspring

Events occurring early in life or prenatally are able to play important roles in the pathogenesis of diseases in adult life. Different sorts of stress or hormonal influences, during particular periods of pregnancy, may result in persistent or transient changes in physiology. IL-1 is a multifunctional cytokine that is involved in bone metabolism. The aim of the present study was to investigate whether exposure to IL-1beta during fetal life has any effect on skeletal growth or bone mineral density in adult rat offspring. Pregnant rats were given intraperitoneal injections of IL-1beta, 1 microg/rat, or saline on days 8, 10, and 12 of gestation. Male IL-1-exposed offspring showed reduced height, areal bone mineral density, and bone mineral content at vertebra L5. Tibial length was reduced in both male and female offspring. Peripheral quantitative computed tomography analyses revealed reduced cortical bone mineral content caused by a decreased cortical cross-sectional area as a result of a decreased cortical thickness, whereas there was no reduction in the amount of trabecular bone in the tibia of male offspring. Our results demonstrate that prenatal exposure to IL-1 can induce specific programming of skeletal tissue. In conclusion, prenatal IL-1 exposure results in decreased skeletal growth and a reduced amount of cortical bone but unchanged trabecular bone mineral density in adult rat offspring.

The pathophysiological role of cytokines

Cytokines are important hormonal mediators, produced in tissues undergoing defence, growth and repair processes. Infection and inflammation in particular result in a cascade of cytokine induction that acts to maintain tissue homeostasis. Most cytokines act within the injured tissues, although some have an endocrine action, recruiting distant tissues in defence of the tissue producing the cytokine and many are important for regulating acquired immunity in secondary lymphoid tissues. Induction of interleukin-1 (IL-1), tumour necrosis factor (TNF) and IL-6 highlight the way in which local tissue cytokine responses are induced and act. Since most cytokines act locally, cytokine measurement presents several difficulties. Only where cytokines (such as IL-6) have a systemic action are plasma cytokine concentrations really meaningful. The presence of cytokine antagonists and soluble cytokine receptors, often released in concert with their respective cytokine agonists, presents additional complexity to interpretation. Measurement and manipulation of cytokines can contribute towards an understanding of their pathophysiological role in both experimental and clinical settings. This includes measurement of plasma IL-6, which has striking relationships to tissue inflammation. Its value is exemplified by some recent studies of stroke patients, where IL-6 reflects not only the initial response but also clinical outcome and survival.