Oral administration of ammonium metavanadate and potassium dichromate distorts the inflammatory reaction induced by turpentine oil injection in male rats.

Heavy metal pollution is rapidly increasing in the environment. It has been shown that exposure to vanadium and chromium is able to alter the immune response. Nevertheless, the mechanisms by which these metal pollutants mediate their immunomodulatory effects are not completely understood. Herein, we examined the effect of ammonium metavanadate and potassium dichromate on the development of an inflammatory response caused by subcutaneous injection of turpentine oil. We demonstrated that pretreatment of rats with ammonium metavanadate and potassium dichromate for two weeks prior to initiation of the inflammatory response resulted in a wider zone of necrosis surrounding the site of inflammation. The acute inflammatory process in the combined model was characterized by elevated serum levels of IL-10 and decreased serum levels of IL-6 as compared to rats not treated with ammonium metavanadate and potassium dichromate. Ammonium metavanadate and potassium dichromate administration induced a decrease in the proportion of splenic His48HighCD11b/c+ myeloid cells accompanied by a reduced infiltration of the wound with neutrophils. Further analysis showed decreased proportions of CD3+CD4+IFNγ+ and CD3+CD4+IL-4+ T cells in the rats with combined model as compared to inflamed rats not treated with ammonium metavanadate and potassium dichromate. The data suggest that consumption of vanadium and chromium compounds disrupts the inflammatory response through an altered balance of pro- and anti-inflammatory cytokines and inhibition of effector T cell activation and neutrophil expansion.

AMPK Serves as a Therapeutic Target Against Anemia of Inflammation.

AIMS: Anemia of inflammation (AI), the second prevalent anemia, is associated with worse prognosis and increased mortality in numerous chronic diseases. We recently reported that the gasotransmitter hydrogen sulfide (H2S) suppressed the inflammatory activation of signal transducer and activator of transcription 3 (STAT3) and hepcidin, the critical mediators of AI. Adenosine 5'-monophosphate-activated protein kinase (AMPK) is a novel inflammatory regulator and might be activated by H2S. In this study, we determined whether AMPK played a role in H2S-mediated anti-inflammatory response in AI and evaluated the therapeutic potential of AMPK against AI by pharmacological and clinical approaches. RESULTS: We showed that AMPK mediated the inhibition of STAT3, hepcidin, and AI by H2S during inflammation. Moreover, pharmacological and genetic activation of AMPK ameliorated hepcidin production, corrected iron dysregulation, and relieved hypoferremia and anemia in both acute and chronic inflammation models in mice. Mechanistic studies indicated that AMPK suppressed STAT3/hepcidin activation by promoting proteasome-mediated Janus kinase 2 (JAK2) degradation, which was dependent on the intact function of suppressor of cytokine signaling 1 (SOCS1) and increased interactions between SOCS1 and JAK2. Most importantly, the AMPK activator metformin was associated with decreased serum hepcidin content and anemia morbidity in Chinese type 2 diabetes mellitus patients. INNOVATION: This is the first study to demonstrate the inhibition of inflammatory hepcidin and AI by AMPK-induced JAK2 degradation. Our work uncovered AMPK as a novel therapeutic target, and metformin as a potential therapy against AI. CONCLUSION: The present work demonstrated that AMPK mediated the therapeutic effects of H2S and relieved AI by promoting SOCS1-mediated JAK2 degradation. Antioxid. Redox Signal. 27, 251-268.

Serum paraoxonase type-1 activity in pigs: assay validation and evolution after an induced experimental inflammation.

Paraoxonase 1 (PON1) is a serum enzyme synthesised and secreted primarily by the liver. It possesses anti-inflammatory properties limiting the production of pro-inflammatory mediators. The objectives of this study were to validate three spectrophotometric assays for the quantification of PON1 activity in pig serum, and to determine if PON1 activity in porcine behaves as a negative acute phase protein (APP), decreasing in inflammatory conditions. An analytical validation using three different substrates - 5-thiobutil butyrolactone (TBBL), phenylacetate (PA) and 4-(p)-nitrophenyl acetate (pNA) - was performed. In addition, inflammation was experimentally induced in five pigs by subcutaneous injection of turpentine oil, while five control pigs were left untreated. The treated pigs showed significant increases in CRP and decreases in albumin, indicating an inflammatory condition. The three substrates used would be suitable for PON1 activity measurements in serum samples, since they offer adequate precision (coefficients of variation<10%), sensitivity (0.01, 0.15, 0.02 U/mL for TBBL, pNA and PA respectively) and accuracy (r=0.99). In addition, PON1 behaves as a negative APP in pigs since a significant decrease (P<0.05) in its activity after 72 h of the induction of the inflammation was observed with all substrates.

Time-dependent effects of localized inflammation on peripheral clock gene expression in rats.

Many aspects of the immune system, including circulating cytokine levels as well as counts and function of various immune cell types, present circadian rhythms. Notably, the mortality rate of animals subjected to high doses of lipopolysaccharide is dependent on the time of treatment. In addition, the severity of symptoms of various inflammatory conditions follows a daily rhythmic pattern. The mechanisms behind the crosstalk between the circadian and immune systems remain elusive. Here we demonstrate that localized inflammation induced by turpentine oil (TURP) causes a time-dependent induction of interleukin (IL)-6 and has time-, gene- and tissue-specific effects on clock gene expression. More precisely, TURP blunts the peak of Per1 and Per2 expression in the liver while in other tissues, the expression nadir is elevated. In contrast, Rev-erbα expression remains relatively unaffected by TURP treatment. Co-treatment with the anti-inflammatory agent IL-1 receptor antagonist (IL-1Ra) did not alter the response of Per2 to TURP treatment in liver, despite the reduced induction of fever and IL-6 serum levels. This indicates that the TURP-mediated changes of Per2 in the liver might be due to factors other than systemic IL-6 and fever. Accordingly, IL-6 treatment had no effect on clock gene expression in HepG2 liver carcinoma cells. Altogether, we show that localized inflammation causes significant time-dependent changes in peripheral circadian clock gene expression, via a mechanism likely involving mediators independent from IL-6 and fever.

Involvement of the essential metal transporter Zip14 in hepatic Cd accumulation during inflammation.

Upregulation of Zip14 contributes to hepatic zinc (Zn) and non-transferrin-bound iron (Fe) uptake during infection and inflammation. We investigated whether this essential metal transporter is also involved in hepatic cadmium (Cd) uptake under these conditions. An injection of lipopolysaccharide (LPS), turpentine oil (Tur) and n-hexane (Hex) resulted in an decrease in plasma Zn and Fe concentrations to 25-50% and an increase in hepatic concentrations of both metals to 150-200% of control mice. LPS significantly increased plasma interleukin (IL)-6 levels more rapidly than Tur or Hex. Tur or Hex significantly increased hepatic Zip14 mRNA expression and decreased ferroportin 1 mRNA expression following continuous increase of IL-6 level. Hepatic Cd and Zn concentrations increased significantly after repeated injections of Cd in Tur- or Hex-treated mice fed a control diet. Treatment with Tur or Hex additionally increased hepatic Cd accumulation in Zn-deficient mice, unlike in Fe-deficient mice. These results suggest that Zn transporters, such as Zip14, may be involved in hepatic Cd uptake during inflammation.

A comparative uptake study of multiplexed PET tracers in mice with turpentine-induced inflammation.

The potential value of multiplexed positron emission tomography (PET) tracers in mice with turpentine-induced inflammation was evaluated and compared with 2-[¹8F]fluoro-2-deoxy-D-glucose ([¹8F]FDG) for glucose metabolism imaging. These PET tracers included [¹8F]fluoromethylcholine ([¹8F]FCH) for choline metabolism imaging, (S-[¹¹C]methyl)-D-cysteine ([¹¹C]DMCYS) for amino acid metabolism imaging, [¹¹C]bis(zinc(II)-dipicolylamine) ([¹¹C]DPA-Zn²âº) for apoptosis imaging, 2-(4-N-[¹¹C]-methylaminophenyl)-6-hydroxybenzothiazole ([¹¹C]PIB) for ß amyloid binding imaging, and [¹8F]fluoride (¹8F⁻) for bone metabolism imaging. In mice with turpentine-induced inflammation mice, the biodistribution of all the tracers mentioned above at 5, 15, 30, 45, and 60 min postinjection was determined. Also, the time-course curves of the tracer uptake ratios for inflammatory thigh muscle (IM) to normal uninflammatory thigh muscle (NM), IM to blood (BL), IM to brain (BR), and IM to liver (LI) were acquired, respectively. Moreover, PET imaging with the tracers within 60 min postinjection on a clinical PET/CT scanner was also conducted. [¹8F]FDG and ¹8F⁻ showed relatively higher uptake ratios for IM to NM, IM to BL, IM to BR, and IM to LI than [¹8F]FCH, [¹¹C]DPA-Zn²âº, [¹¹C]DMCYS and [¹¹C]PIB, which were highly consistent with the results delineated in PET images. The results demonstrate that ¹8F⁻ seems to be a potential PET tracer for inflammation imaging. [¹8F]FCH and [¹¹C]DMCYS, with lower accumulation in inflammatory tissue than [¹8F]FDG, are not good PET tracers for inflammation imaging. As a promising inflammatory tracer, the chemical structure of [¹¹C]DPA-Zn²âº needs to be further optimized.

Ferroportin-1 is a 'nuclear'-negative acute-phase protein in rat liver: a comparison with other iron-transport proteins.

Liver is the central organ of iron metabolism. During acute-phase-response (APR), serum iron concentration rapidly decreases. The current study aimed to compare expression and localization of iron transport protein ferroportin-1 (Fpn-1) and of other iron import proteins after experimental tissue damage induced by injecting turpentine oil in the hind limbs of rats and mice. Serum and spleen iron concentration decreased with an increase in total liver, cytoplasmic and nuclear iron concentration. In liver, mRNA amount of Fpn-1, Fpn-1a, Fpn-1b, HFE, hemojuvelin (HJV) and hephaestin (heph) genes showed a rapid decrease. Hepcidin, divalent metal transporter-1 (DMT-1), transferrin (Tf) and Tf-receptor-1 (TfR1), TfR-2 (TfR2) gene expression was increased. Western blot analysis of liver tissue lysate confirmed the changes observed at mRNA level. In spleen, a rapid decrease in gene expression of Fpn-1, Fpn-1a, Fpn-1b, DMT-1, Tf, TfR1 and TfR2, and an increase in hepcidin was observed. Immunohistochemistry of DMT-1 and TfR2 were mainly detected in the nucleus of rat liver and spleen, whereas TfR1 was clearly localized in the plasma membrane. Fpn-1 was mostly found in the nuclei of liver cells, whereas in spleen, the protein was mainly detected in the cell membrane. Western blot analysis of liver fractions confirmed immunohistochemical results. In livers of wild-type mice, gene expression of Fpn-1, Fpn-1a and Fpn-1b was downregulated, whereas hepcidin gene expression was increased. In contrast, these changes were less pronounced in IL-6ko-mice. Cytokine (IL-6, IL-1b and TNF-a) treatment of rat hepatocytes showed a downregulation of Fpn-1, Fpn-1a and Fpn-1b, and upregulation of hepcidin gene expression. Moreover, western blot analysis of cell lysate of IL-6-treated hepatocytes detected, as expected, an increase of a2-macroglobulin (positive acute-phase protein), whereas albumin (negative acute-phase protein) and Fpn-1 were downregulated. Our results demonstrate that liver behaves as a 'sponge' for iron under acute-phase conditions, and Fpn-1 behaves as a negative acute-phase protein in rat hepatocytes mainly, but not exclusively, because of the effect of IL-6. These changes could explain iron retention in the cytoplasm and in the nucleus of hepatocytes during APR.

Michelangelo's eye disease.

Charged by the Pope Julius II for painting the Cappella Sistina in Rome (between 1508 and 1512), Michelangelo worked in an elevated scaffolding, in an anomalous position with dyes (including poisoning lead salts) and solvents (such as toxic turpentine) dripping on his face and continuously inhaling, in a dim environment illuminated only with oil lamps and candles, as he described himself and sketched in a sonet addressed to Giovanni da Pistoia. In 1510 he began suffering from eye disease: the main symptom was the necessity to elevate the document he was reading up to the level of his eyes. This defect disappeared few months after he finished painting his masterpiece. We hypothesize that the Michelangelo's eyes disease was a form of acquired and transitory nystagmus induced by the many hours he spent in up gaze, with a skew deviation, a form of ocular tilt reaction resulting from the impairment of spatial sensitivity (inversion illusion) due to the persistence of the artist's head in a horizontal position, looking upward.

STAT3/NF-κB interactions determine the level of haptoglobin expression in male rats exposed to dietary restriction and/or acute phase stimuli.

Haptoglobin is a constitutively expressed protein which is predominantly synthesized in the liver. During the acute-phase (AP) response haptoglobin is upregulated along with other AP proteins. Its upregulation during the AP response is mediated by cis-trans interactions between the hormone-responsive element (HRE) residing in the haptoglobin gene and inducible transcription factors STAT3 and C/EBP ß. In male rats that have been subjected to chronic 50% dietary restriction (DR), the basal haptoglobin serum level is decreased. The aim of this study was to characterize the trans-acting factor(s) responsible for the reduction of haptoglobin expression in male rats subjected to 50% DR for 6 weeks. Protein-DNA interactions between C/EBP and STAT families of transcription factors and the HRE region of the haptoglobin gene were examined in livers of male rats subjected to DR, as well as during the AP response that was induced by turpentine administration. In DR rats, we observed associations between the HRE and C/EBPα/ß, STAT5b and NF-κB p50, and the absence of interactions between STAT3 and NF-kB p65. Subsequent induction of the AP response in DR rats by turpentine administration elicited a normal, almost 2-fold increase in the serum haptoglobin level that was accompanied by HRE-binding of C/EBPß, STAT3/5b and NF-kB p65/p50, and the establishment of interaction between STAT3 and NF-κB p65. These results suggest that STAT3 and NF-κB p65 crosstalk plays a central role while C/EBPß acquires an accessory role in establishing the level of haptoglobin gene expression in male rats exposed to DR and AP stimuli.

Acute phase protein response in the capybara (Hydrochoerus hydrochaeris).

We evaluated the acute phase protein response in capybaras (Hydrochoerus hydrochaeris). Three animal groups were used: 1) healthy animals (n=30), 2) a group in which experimental inflammation with turpentine was induced (n=6), and 3) a group affected with sarcoptic scabies (n=14) in which 10 animals were treated with ivermectin. Haptoglobin (Hp), acid-soluble glycoprotein (ASG) and albumin were analyzed in all animals. In those treated with turpentine, Hp reached its maximum value at 2 wk with a 2.7-fold increase, whereas ASG increased 1.75-fold and albumin decreased 0.87-fold 1 wk after the induction of inflammation. Capybaras affected with sarcoptic scabies presented increases in Hp and ASG of 4.98- and 3.18-fold, respectively, and a 0.87-fold decrease in albumin, compared with healthy animals. Haptoglobin and ASG can be considered as moderate, positive acute phase proteins in capybaras because they showed less than 10-fold increases after an inflammatory process and reached their peak concentrations 1 wk after the induction of inflammation. Conversely, albumin can be considered a negative acute phase protein in capybaras because it showed a reduction in concentration after inflammatory stimulus.

Relationship between production of acute-phase proteins and strength of inflammatory stimulation in rats.

The relationship between intensity of inflammatory stimulation and production of α(2)-macroglobulin (α2M) and α(1)-acid glycoprotein (AAG) in rats was investigated. Sprague-Dawley rats were injected with turpentine oil at doses of 0.05, 0.2 or 0.4 mL/rat. Serum levels of α2M, interleukin (IL)-6 and cytokine-induced neutrophil chemoattractant-1 (CINC-1) were measured by enzyme-linked immunosorbent assay, and AAG was measured by single radial immunodiffusion. Peak serum levels of α2M and AAG in rats injected at 0.05 mL/rat were significantly lower than those at 0.2 or 0.4 mL/rat. However, no significant differences were observed for peak serum levels of these acute-phase proteins between 0.2 and 0.4 mL/rat. Furthermore, peak serum levels of IL-6 and CINC-1 in rats injected at 0.05 mL/rat were significantly lower than those at 0.2 or 0.4 mL/rat. Thus, the production of these acute-phase proteins has upper limits, even under increased strength of inflammatory stimulation in rats injected with turpentine oil.

Optimal combinations of acute phase proteins for detecting infectious disease in pigs.

The acute phase protein (APP) response is an early systemic sign of disease, detected as substantial changes in APP serum concentrations and most disease states involving inflammatory reactions give rise to APP responses. To obtain a detailed picture of the general utility of porcine APPs to detect any disease with an inflammatory component seven porcine APPs were analysed in serum sampled at regular intervals in six different experimental challenge groups of pigs, including three bacterial (Actinobacillus pleuropneumoniae, Streptococcus suis, Mycoplasma hyosynoviae), one parasitic (Toxoplasma gondii) and one viral (porcine respiratory and reproductive syndrome virus) infection and one aseptic inflammation. Immunochemical analyses of seven APPs, four positive (C-reactive protein (CRP), haptoglobin (Hp), pig major acute phase protein (pigMAP) and serum amyloid A (SAA)) and three negative (albumin, transthyretin, and apolipoprotein A1 (apoA1)) were performed in the more than 400 serum samples constituting the serum panel. This was followed by advanced statistical treatment of the data using a multi-step procedure which included defining cut-off values and calculating detection probabilities for single APPs and for APP combinations. Combinations of APPs allowed the detection of disease more sensitively than any individual APP and the best three-protein combinations were CRP, apoA1, pigMAP and CRP, apoA1, Hp, respectively, closely followed by the two-protein combinations CRP, pigMAP and apoA1, pigMAP, respectively. For the practical use of such combinations, methodology is described for establishing individual APP threshold values, above which, for any APP in the combination, ongoing infection/inflammation is indicated.

Inhibition of bone morphogenetic protein signaling attenuates anemia associated with inflammation.

Anemia of inflammation develops in settings of chronic inflammatory, infectious, or neoplastic disease. In this highly prevalent form of anemia, inflammatory cytokines, including IL-6, stimulate hepatic expression of hepcidin, which negatively regulates iron bioavailability by inactivating ferroportin. Hepcidin is transcriptionally regulated by IL-6 and bone morphogenetic protein (BMP) signaling. We hypothesized that inhibiting BMP signaling can reduce hepcidin expression and ameliorate hypoferremia and anemia associated with inflammation. In human hepatoma cells, IL-6-induced hepcidin expression, an effect that was inhibited by treatment with a BMP type I receptor inhibitor, LDN-193189, or BMP ligand antagonists noggin and ALK3-Fc. In zebrafish, the induction of hepcidin expression by transgenic expression of IL-6 was also reduced by LDN-193189. In mice, treatment with IL-6 or turpentine increased hepcidin expression and reduced serum iron, effects that were inhibited by LDN-193189 or ALK3-Fc. Chronic turpentine treatment led to microcytic anemia, which was prevented by concurrent administration of LDN-193189 or attenuated when LDN-193189 was administered after anemia was established. Our studies support the concept that BMP and IL-6 act together to regulate iron homeostasis and suggest that inhibition of BMP signaling may be an effective strategy for the treatment of anemia of inflammation.

Changes in gene expression of DOR and other thyroid hormone receptors in rat liver during acute-phase response.

Non-thyroidal illness is characterized by low tri-iodothyronine (T3) serum level under acute-phase conditions. We studied hepatic gene expression of the newly identified thyroid hormone receptor (TR) cofactor DOR/TP53INP2 together with TRs in a rat model of aseptic abscesses induced by injecting intramuscular turpentine-oil into each hind limb. A fast (4-6 h) decrease in the serum level of free thyroxine and free T3 was observed. By immunohistology, abundant DOR protein expression was detected in the nuclei of hepatocytes and ED-1(+) (mononuclear phagocytes), CK-19(+) (biliary cells), and SMA(+) (mesenchymal cells of the portal tract) cells. DOR signal was reduced with a minimum at 6-12 h after the acute-phase reaction (APR). Immunohistology also showed a similar pattern of protein expression in TRα1 but without a significant change during APR. Transcripts specific for DOR, nuclear receptor co-repressor 1 (NCoR-1), and TRß1 were down-regulated with a minimum at 6-12 h, whereas expression for TRα1 and TRα2 was slightly and significantly up-regulated, respectively, with a maximum at 24 h after APR was initiated. In cultured hepatocytes, acute-phase cytokines interleukin-1ß (IL-1ß) and IL-6 down-regulated DOR and TRß1 at the mRNA level. Moreover, gene expression of DOR and TRs (TRα1, TRα2, and TRß1) was up-regulated in hepatocytes by adding T3 to the culture medium; this up-regulation was almost completely blocked by treating the cells with IL-6. Thus, TRß1, NCoR-1, and the recently identified DOR/TP53INP2 are abundantly expressed and down-regulated in liver cells during APR. Their down-regulation is attributable to the decreased serum level of thyroid hormones and most probably also to the direct action of the main acute-phase cytokines.

STAT3 signaling within hepatocytes is required for anemia of inflammation in vivo.

BACKGROUND: Anemia of inflammation, commonly observed in patients with chronic diseases, is associated with decreased serum iron. Hepcidin, mainly produced by hepatocytes in a STAT3- and/or SMAD-dependent manner, is involved in iron homeostasis. What remains to be established is whether or not the hepatic IL-6/STAT3 signal has a role in anemia of inflammation in vivo. METHODS: Turpentine oil was subcutaneously injected into wild-type mice or hepatocyte-specific STAT3-deficient mice (L-STAT3KO) to induce inflammation. RESULTS: Turpentine injection increased serum IL-6 levels. It activated liver STAT3 in wild-type mice, but not in L-STAT3KO mice. In chronic inflammation, wild-type mice showed decreased serum iron levels and anemia with up-regulation of hepcidin levels in the liver. In contrast, L-STAT3KO mice showed no increase in hepatic hepcidin levels or anemia. CONCLUSIONS: Liver STAT3 is critically involved in the development of anemia of inflammation via the expression of hepcidin. The liver regulates anemia of inflammation through STAT3 signaling.

Hepatic changes of erythropoietin gene expression in a rat model of acute-phase response.

An acute-phase response is the systemic reaction of an organism to insult (e.g. infection, trauma and burning). It represents the 'first line' of defence of the body to tissue-damaging attacks. In the present work, we used a rat model of an intra-muscular turpentine oil (TO) injection to analyse erythropoietin (EPO) gene expression changes in the liver, one of the main target organs of acute-phase cytokines. EPO began to increase in the serum of TO-treated animals 6 h after injection and reached a maximum at 24 h (125+/-20 pg/ml). The detection of total RNA by polymerase chain reaction analysis showed that the levels of EPO gene expression in the liver were considerably increased between 2 and 12 h by up to 20-fold at the peak after TO administration, followed by a gradual decrease over the next 48 h, although the values remained significantly higher compared with the control group. In the kidney, after a sudden slight increase, the values declined progressively to 3.5-fold decrease at 12 h after the injection. In the liver, a parallel upregulation of the hypoxia-inducible factor-1 (HIF-1) alpha gene was observed (up to 4.7-fold increase), while HIF-2 alpha gene expression remained unaltered. On the other hand, the protein of both genes became detectable after the injection and increased progressively over 24 h, with a subsequent decline. These results suggest that EPO may be added to the increasing group of positive acute-phase proteins and the liver might represent the major source of the hormone under these conditions in the rat.

Kinetics of {alpha}2-macroglobulin and {alpha}1-acid glycoprotein in rats subjected to repeated acute inflammatory stimulation.

The kinetics of alpha(2)-macroglobulin (alpha2M) and alpha(1)-acid glycoprotein (AAG) in rats repeatedly stimulated with intramuscular injections of turpentine oil at doses 0.05 and 0.4 mL/rat were investigated. Mean serum levels of alpha2M peaked at 48 h after the first turpentine oil injection, reaching 1.74 and 2.36 mg/mL at 0.05 and 0.4 mL/rat, respectively. AAG peaks were also observed at 48 h after injection, and the mean values were 2.02 and 2.53 mg/mL, respectively. These peak values of alpha2M and AAG differed significantly between the 0.05 and 0.4 mL/rat injection groups. Mean serum levels of interleukin-6 (IL-6) at 0.05 mL/rat were 52.61 pg/mL at 12 h, 48.86 pg/mL at 36 h and 81.93 pg/mL at 84 h after the first injection. Mean IL-6 serum levels at 0.4 mL/rat were 215.24 pg/mL at 12 h, 56.33 pg/mL at 36 h and 39.25 pg/mL at 84 h after the first injection. Mean serum levels of cytokine-induced chemoattractant-1 (CINC-1) at a dose of 0.05 mL/rat were 5.70 ng/mL at 12 h, 5.58 ng/mL at 36 h and 4.58 ng/mL at 84 h after the first injection. Mean serum levels of CINC-1 after injection at 0.4 mL/rat were 11.57 ng/mL at 12 h, 4.68 ng/mL at 36 h and 4.42 ng/mL at 84 h. Serum levels of IL-6 differed significantly at 12, 24, 72 and 84 h, while those of CINC-1 differed significantly at 12, 24, 48 and 96 h between the 0.05 and 0.4 mL/rat injection groups. Differences in peak serum levels in the 0.05 and 0.4 mL/rat groups were attributed to differences in the production of IL-6 and CINC-1, which are thought to contribute to alpha2M and AAG production.

Occupational asthma due to turpentine in art painter--case report.

Turpentine is a fluid obtained by distillation of wood resins containing mixture of terpens. It can act as an irritant and sensitiser. Most common health problem among workers exposed to turpentine is contact dermatitis. Little is know about turpentine to cause type I hypersensitivity reaction. We present a case of a 27-year old art painter using turpentine as a thinner for oil-based paints. She developed asthmatic reactions after 5 years of working with turpentine. A number of clinical procedures were performed, including clinical examination, routine laboratory tests, total serum IgE, skin prick tests to common aeroallergens, metal salts, oil-based paints and balsamic turpentine, resting spirometry test, histamine challenge, and a single-blind, placebo-controlled specific inhalation challenge with balsamic turpentine. Clinical findings and laboratory test results were normal but a significant bronchial hyperreactivity was found. During the specific challenge, dyspnoea and decreased forced expiratory volume (FEV1) were observed in late phase of asthmatic reaction. An increased proportion of eosinophils in induced sputum could also be noted 24 h after the challenge. Positive clinical response to the specific challenge as well as the morphological changes found in induced sputum served as the basis for diagnosing occupational asthma. To our knowledge, this is the first well-documented case of turpentine-induced occupational asthma.