Expression of types I, III and IV collagen genes in fibrotic skin and nerve lesions of toxic oil syndrome patients

Chemical exposure-induced systemic fibrosing disorders: Novel insights into systemic sclerosis etiology and pathogenesis

Numerous drugs and chemical substances are capable of inducing exaggerated tissue fibrotic responses. The vast majority of these agents cause localized fibrotic tissue reactions or fibrosis confined to specific organs. Although much less frequent, chemically-induced systemic fibrotic disorders have been described, sometimes occurring as temporally confined outbreaks. These include the Toxic Oil Syndrome (TOS), the Eosinophilia-Myalgia Syndrome (EMS), and Nephrogenic Systemic Fibrosis (NSF). Although each of these disorders displays some unique characteristics, they all share crucial features with Systemic Sclerosis (SSc), the prototypic idiopathic systemic fibrotic disease, including vasculopathy, chronic inflammatory cell infiltration of affected tissues, and cutaneous and visceral tissue fibrosis. The study of the mechanisms and molecular alterations involved in the development of the chemically-induced systemic fibrotic disorders has provided valuable clues that may allow elucidation of SSc etiology and pathogenesis. Here, we review relevant aspects of the TOS, EMS, and NSF epidemic outbreaks of chemically-induced systemic fibrosing disorders that provide strong support to the hypothesis that SSc is caused by a toxic or biological agent that following its internalization by endothelial cells induces in genetically predisposed individuals a series of molecular alterations that result in the development of SSc clinical and pathological alterations.

Color Doppler ultrasound assessment of morphology and types of fistulous tracts in hidradenitis suppurativa (HS)

BACKGROUND

Fistulous tracts in hidradenitis suppurativa (HS) are key signs of severity and their clinical evaluation alone may be limited for assessing their presence and morphology. There is also a need to determine the factors that allow reversibility of the anatomic changes in HS.

OBJECTIVE

We sought to categorize fistulous tracts in HS.

METHODS

A retrospective study of color Doppler ultrasound images of cases with positive clinical and sonographic criteria of HS with fistulous tracts was performed. The sonographic staging of HS, location, and anatomic characteristics of the tracts were registered and graded. Statistical analysis for correlating variables was performed using bivariate and multivariate studies.

RESULTS

In all, 52 patients presenting 96 fistulous tracts met the criteria. Morphology was defined and a sonographic classification into 3 types of fistulae was developed. Type 3 concentrated 71% of the cases presenting communicating tracts, and type 2, 29%. Types 2 and 3 represented 63% of patients with multiple fistulous tracts. Fistulous tracts types 2 and 3 were significantly correlated with age 35 years or older and groin location.

LIMITATIONS

Ultrasound cannot detect lesions less than 0.1 mm.

CONCLUSION

Fistulous tracts in HS can be categorized using ultrasound, which may support earlier and more precise management.

Low-dose irradiation affects expression of inflammatory markers in the heart of ApoE -/- mice

Epidemiological studies indicate long-term risks of ionizing radiation on the heart, even at moderate doses. In this study, we investigated the inflammatory, thrombotic and fibrotic late responses of the heart after low-dose irradiation (IR) with specific emphasize on the dose rate. Hypercholesterolemic ApoE-deficient mice were sacrificed 3 and 6 months after total body irradiation (TBI) with 0.025, 0.05, 0.1, 0.5 or 2 Gy at low (1 mGy/min) or high dose rate (150 mGy/min). The expression of inflammatory and thrombotic markers was quantified in frozen heart sections (CD31, E-selectin, thrombomodulin, ICAM-1, VCAM-1, collagen IV, Thy-1, and CD45) and in plasma samples (IL6, KC, MCP-1, TNFα, INFγ, IL-1β, TGFβ, INFγ, IL-10, sICAM-1, sE-selectin, sVCAM-1 and fibrinogen) by fluorescence analysis and ELISA. We found that even very low irradiation doses induced adaptive late responses, such as increases of capillary density and changes in collagen IV and Thy-1 levels indicating compensatory regulation. Slight decreases of ICAM-1 levels and reduction of Thy 1 expression at 0.025–0.5 Gy indicate anti-inflammatory effects, whereas at the highest dose (2 Gy) increased VCAM-1 levels on the endocardium may represent a switch to a pro-inflammatory response. Plasma samples partially confirmed this pattern, showing a decrease of proinflammatory markers (sVCAM, sICAM) at 0.025–2.0 Gy. In contrast, an enhancement of MCP-1, TNFα and fibrinogen at 0.05–2.0 Gy indicated a proinflammatory and prothrombotic systemic response. Multivariate analysis also revealed significant age-dependent increases (KC, MCP-1, fibrinogen) and decreases (sICAM, sVCAM, sE-selectin) of plasma markers. This paper represents local and systemic effects of low-dose irradiation, including also age- and dose rate-dependent responses in the ApoE^-/- mouse model. These insights in the multiple inflammatory/thrombotic effects caused by low-dose irradiation might facilitate an individual evaluation and intervention of radiation related, long-term side effects but also give important implications for low dose anti-inflammatory radiotherapy.

The nervous system in systemic sclerosis (scleroderma). Clinical features and pathogenetic mechanisms

The involvement of the nervous system in SSc is well recognized today. Different pathogenetic mechanisms are suggested that may alternatively explain the multiform appearance of the clinical spectrum (mononeuritis, mononeuritis multiplex, carpal tunnel syndrome, and so forth). It is now clear that the ANS is the earliest structure targeted by the disease in the gastrointestinal tract. The importance of this observation has not yet been adequately interpreted but may, together with the increasing evidence of the nervous system involvement in SSc, become a leading factor in understanding of the importance of the nervous system in the onset, development, and maintenance of the disease.

Toxic oil stimulates collagen synthesis acting at a pretranslational level in cultured fat-storing cells

BACKGROUND/AIMS

The toxic oil syndrome appeared in Spain in 1981 as a result of ingestion of rapeseed oil denatured with aniline. Some patients developed scleroderma-like skin lesions and liver cirrhosis. Mechanisms of these fibrotic lesions are not known. The present study was designed to investigate the effect of toxic oils on collagen metabolism.

METHODS

We measured the relative rate of collagen production, absolute rate of collagen synthesis, production, secretion, and degradation, proline transport, steady-state levels of procollagen alpha 1(l)-messenger RNA (mRNA) in cultured fat-storing cells, and chloramphenicol acetyltransferase activity in transfected cells.

RESULTS

Toxic oils increased collagen synthesis, procollagen alpha 1(l)-mRNA levels, and chloramphenicol acetyltransferase activity in cultured fat-storing cells. Effect on collagen production correlated with lipid peroxide content in oils. Cycloheximide, alpha-tocopherol, and methylene blue prevented the increase in procollagen alpha 1(l)-mRNA. Oleylanilide and linoleylanilide, markers for toxic oils, reproduced the stimulatory effects of toxic oils on collagen production and procollagen alpha 1(l)-mRNA.

CONCLUSIONS

Toxic oils increased collagen synthesis by acting on the promoter of procollagen alpha 1(l) gene, probably through lipid peroxides derived from acylanilides. We suggest that toxic oil may have stimulated procollagen gene expression through the formation of adducts of aldehydes with some transcription factor.