The prevalence of hairy leukoplakia was determined among 176 symptomatic HIV seropositive patients seen at the outpatient department of the Institute of Tropical Medicine in Antwerp, Belgium. Moreover, systematic tongue biopsies were performed during postmortem examination of 21 patients with AIDS, 100 HIV seronegative immunocompromised patients with haematologic or other malignancies and 100 HIV seronegative non-immunocompromised patients who died at the University Hospital Antwerp. Hairy leukoplakia was observed in 52 (29.5%) of the outpatients, but only in one (5%) of the AIDS patients in the postmortem study (P = 0.03). An explanation for this difference may be that significantly more AIDS patients who died had received either acyclovir or ganciclovir during the 3 months prior to the postmortem examination than the HIV seropositive outpatients during the 3 months prior to examination. Hairy leukoplakia occurred more often in Caucasian homosexual men with HIV infection (38%) than among heterosexual Africans with HIV infection (17%) (P = 0.06). Hairy leukoplakia was observed in none of the HIV seronegative patients.
KW-2149 is a new, semisynthetic, C-7-N-Substituted, mitomycin C analog showing antitumor activity both in vitro and in vivo, equal or superior to mitomycin C. In a phase I study, KW-2149 was administered as an i.v. bolus injection every 21 days and at a dose of 100 mg/m2 pulmonary toxicity was dose limiting. Animal studies have indicated since that KW-2149-induced pulmonary toxicity can be prevented by pretreatment with corticosteroids. This paper presents the results of a further phase I study of KW-2149 with corticosteroid pretreatment. Patients were treated with oral dexamethasone 8 mg every 12 h, starting 24 h before KW-2149 administration, for 5 days. KW-2149 was given as an i.v. bolus injection every 21 days. Seventeen patients were treated with a total of 48 courses. Six patients received 60 mg/m2 and 11 patients 75 mg/m2. Two courses were not evaluable for toxicity. Significant lung toxicity was observed in at least three patients treated with a dose of 75 mg/m2 KW-2149 and pulmonary toxicity was therefore considered the dose-limiting toxicity at 75 mg/m2. No other important side effects were noted. One partial response was observed in a patient with colorectal cancer. Pretreatment with dexamethasone failed to suppress KW-2149-induced lung toxicity.
The neuregulin-1 (NRG-1)/receptor tyrosine-protein kinase erbB (ErbB) system is an endothelium-controlled paracrine system modulating cardiac performance and adaptation. Recent studies have indicated that NRG-1 has antifibrotic effects in the left ventricle, which were explained by direct actions on cardiac fibroblasts. However, the NRG-1/ErbB system also regulates the function of macrophages. In this study, we hypothesized that the antifibrotic effect of NRG-1 in the heart is at least partially mediated through inhibitory effects on macrophages. We also hypothesized that the antifibrotic effect of NRG-1 may be active in other organs, such as the skin and lung. First, in a mouse model of angiotensin II (ANG II)-induced myocardial hypertrophy and fibrosis, NRG-1 treatment (20 µg·kg −1 ·day −1 ip) significantly attenuated myocardial hypertrophy and fibrosis and improved passive ventricular stiffness (4 wk). Interestingly, 1 wk after exposure to ANG II, NRG-1 already attenuated myocardial macrophage infiltration and cytokine expression. Furthermore, mice with myeloid-specific deletion of the ErbB4 gene ( ErbB4 F/F LysM-Cre +/− ) showed an intensified myocardial fibrotic response to ANG II. Consistently, NRG-1 activated the ErbB4 receptor in isolated macrophages, inhibited phosphatidylinositide 3-kinase/Akt and STAT3 signaling pathways, and reduced the release of inflammatory cytokines. Further experiments showed that the antifibrotic and anti-inflammatory effects of NRG-1 were reproducible in mouse models of bleomycin-induced dermal and pulmonary fibrosis. Overall, this study demonstrates that the antifibrotic effect of NRG-1 in the heart is linked to anti-inflammatory activity NRG-1/ErbB4 signaling in macrophages. Second, this study shows that NRG-1 has antifibrotic and anti-inflammatory effects in organs other than the heart, such as the skin and lung. NEW & NOTEWORTHY Our study contributes to the understanding of the antifibrotic effect of neuregulin-1 during myocardial remodeling. Here, we show that the antifibrotic effect of neuregulin-1 is at least partially mediated through anti-inflammatory activity, linked to receptor tyrosine-protein kinase erbB-4 activation in macrophages. Furthermore, we show that this effect is also present outside the heart. Listen to this article’s corresponding podcast at http://ajpheart.podbean.com/e/nrg-1-inhibits-macrophage-activation-during-tissue-fibrosis/ .
Evidence is accumulating that autophagy occurs in advanced atherosclerotic plaques. Although there is an almost relentless discovery of molecules that are involved in autophagy, studies of selective autophagy induction or inhibition using knockout mice are just now beginning to reveal its biological significance. Most likely, autophagy safeguards plaque cells against cellular distress, in particular oxidative injury, by degrading the damaged intracellular material. In this way, autophagy is protective and contributes to cellular recovery in an unfavorable environment. Pharmacological approaches have recently been developed to stabilize vulnerable, rupture-prone lesions through induction of autophagy. This approach has proven to be successful in short-term studies. However, how autophagy induction affects processes such as inflammation remains to be elucidated and is currently under investigation. This review highlights the possibilities for exploiting autophagy as a drug target for plaque stabilization.
