Diabetic glomerulosclerosis is defined by increased glomerular extracellular matrix (ECM) that is mainly synthesized by mesangial cells that underwent an activation mediated by cytokines and growth factors from various cellular origins. In this study, we tested whether macrophages could infiltrate the glomeruli and influence ECM synthesis in experimental diabetes. To test our hypothesis, we initially studied the dynamics of glomerular macrophage recruitment in streptozotocin-induced diabetic rats at days 1, 2, 4, 8, 15, and 30 by using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) on isolated glomeruli and immunohistochemistry and morphometry. We then assessed the role of macrophages on the basis of the pharmacological modulation of their recruitment by insulin or ACE inhibitor treatments and by X-irradiation-induced macrophage depletion at days 8 and 30. Macrophages were recruited within the glomeruli at the very early phase of hyperglycemia by using RT-P C R CD14 detection from day 2 and by using ED1 immunohistochemistry from day 8. This glomerular macrophage infiltration was associated with an increase in 1 -chain type IV collagen mRNA. In parallel, the diabetic glomeruli became hypertrophic with an increase in the mesangial area. Macrophage recruitment was preceded by or associated with an increased glomerular expression of vascular cell adhesion molecule 1, intracellular adhesion molecule 1, and monocyte chemoattractant protein 1, which contributes to monocyte diapedesis. Glomerular interleukin-1 mRNA synthesis was also enhanced as early as day 1 and could be involved in the increase in ECM and adhesion molecule gene expressions. Insulin treatment and irradiationinduced macrophage depletion completely prevented the glomerular macrophage recruitment and decreased 1 -chain type IV collagen mRNA and mesangial area in diabetic rats, whereas ACE inhibitor treatment had an incomplete effect. It can be concluded that in the streptozotocin model, hyperglycemia is followed by an early macrophage recruitment that contributes to the molecular and structural events that could lead to glomerulosclerosis. Therefore, besides direct stimulation of mesangial cells by hyperglycemia, macrophages recruited in the glomeruli during the early phase of hyperglycemia could secondarily act on mesangial c e l l s . Diabetes 4 9 :4 6 6-475, 2000

Fibrosis following breast radiotherapy for mammary cancer is a frequent undesired effect with objective (esthetic) and subjective (pain) consequences. Forty‐four patients with clinical radiofibrosis following conservative treatment of breast cancer were evaluated for the local antifibrosis effect of copper zinc superoxide dismutase [SOD(Cu/Zn)]. Extracted SOD(Cu/Zn) in a concentration of 3,600 units/mg was applied as ointment to the fibrotic affected area, b.i.d. for 90 days, in a total dose of 40 mg. The radiofibrosis intensity was scored on the basis of clinical criteria (pain and the fibrosis area) before and after SOD(Cu/Zn) treatment. SOD(Cu/Zn) was found to be effective in reducing radiation induced fibrosis by a lowering pain score in 36/39 patients and a decrease of the fibrotic area size in half cases, after 6 months. The intensity and changes of breast fibrosis were assessed also by mammography and, for the topographical distribution of subcutaneous temperature, by infrared thermography. Mammography density suggested decreased fibrosis in one third of patients. Thermography showed that fibrosis was accompanied by two zones clinically indistinctive: a central area with maximum thermal activity, called “Maximal Thermic zone” (MTZ) and a peripheral area with less thermal activity but higher than in the surrounding normal tissue, “Transitional Thermic Zone” (TTZ). Both MTZ and TTZ were significantly decreased in 36/44 patients after SOD(Cu/Zn) treatment. Clinical changes persisted all along the study. Treatment was well tolerated except for one case of local allergic reaction, and no important side effects. Molecular mechanisms involved are discussed. Further studies are running to confirm and explain these results.

The Watson-Crick base pairing rule provides the underlying principle for the antisense (AS) approach to inhibiting gene expression. Transforming growth factor alpha (TGFalpha) was the first growth factor to be associated with tumorigenesis, thus making the TGFalpha (mRNA) a potential target for AS therapy and offering the potential for monitoring of the progression of malignancy by non-invasive imaging with radiolabelled AS phosphodiester. Probe labelling and biodistribution were studied in the present report. A 23-mer oligonucleotide sequence was synthesized and grafted in 5' with a tyramine group which was further radioiodinated. The radiolabelled AS was injected intratumorally in mammary tumour-bearing BALB/c mice (3 weeks after inoculation of 7.10(6)NS2T2A mammary cells). Biodistribution was monitored by sequential scintigraphy and organ radioactivity after autopsy. The 5' tyramine group allowed specific and stable radiolabelling of the AS with 125I. The 125I AS oligonucleotide was rapidly cleared from the tumour by intestine and kidneys. Four hours after intratumoral injection, 6.5%+/-1.5% of the dose was retained in the tumour as non-degraded 125I AS. It is concluded that 5' tyraminylated AS provides information on the biodistribution of AS oligonucleotide following intratumoral injection. These data will contribute to the pharmacology of AS oligonucleotides which can be used for therapy.

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