The role of atopy in the pathogenesis of bleomycin pulmonary toxicity

Vincamine Ameliorates Epithelial-Mesenchymal Transition in Bleomycin-Induced Pulmonary Fibrosis in Rats; Targeting TGF-β/MAPK/Snai1 Pathway

Idiopathic pulmonary fibrosis is a progressive, irreversible lung disease that leads to respiratory failure and death. Vincamine is an indole alkaloid obtained from the leaves of Vinca minor and acts as a vasodilator. The present study aims to investigate the protective activity of vincamine against EMT in bleomycin (BLM)-induced pulmonary fibrosis via assessing the apoptotic and TGF-β1/p38 MAPK/ERK1/2 signaling pathways. In bronchoalveolar lavage fluid, protein content, total cell count, and LDH activity were evaluated. N-cadherin, fibronectin, collagen, SOD, GPX, and MDA levels were determined in lung tissue using ELISA. Bax, p53, bcl2, TWIST, Snai1, and Slug mRNA levels were examined using qRT-PCR. Western blotting was used to assess the expression of TGF-β1, p38 MAPK, ERK1/2, and cleaved caspase 3 proteins. H & E and Masson's trichrome staining were used to analyze histopathology. In BLM-induced pulmonary fibrosis, vincamine reduced LDH activity, total protein content, and total and differential cell count. SOD and GPX were also increased following vincamine treatment, while MDA levels were decreased. Additionally, vincamine suppressed the expression of p53, Bax, TWIST, Snail, and Slug genes as well as the expression of factors such as TGF-β1, p/t p38 MAPK, p/t ERK1/2, and cleaved caspase 3 proteins, and, at the same time, vincamine increased bcl2 gene expression. Moreover, vincamine restored fibronectin, N-Catherine, and collagen protein elevation due to BLM-induced lung fibrosis. In addition, the histopathological examination of lung tissues revealed that vincamine attenuated the fibrotic and inflammatory conditions. In conclusion, vincamine suppressed bleomycin-induced EMT by attenuating TGF-β1/p38 MAPK/ERK1/2/TWIST/Snai1/Slug/fibronectin/N-cadherin pathway. Moreover, it exerted anti-apoptotic activity in bleomycin-induced pulmonary fibrosis.

A case of bleomycin-induced flagellate dermatitis: A case report

The article description and significance to dermatologists: bleomycin flagellate dermatitis is a rare cutaneous manifestation, believed to be due to the lack of bleomycin hydrolase enzyme in the skin, which inactivates bleomycin, resulting in its accumulation. This is thought to be a dose-dependent reaction, and doses over 200 U and higher may increase risk. This case describes a male developing a pruritic, erythematous linear flagellated dermatitis to the lower back after his third cycle of bleomycin, etoposide and cisplatin for a stage 3 seminoma. Pruritis resolved and erythema improved with the treatment of bilastine and desoximetasone cream. It is important to recognize this condition because untreated pruritis may lead to increased impairment of the skin barrier in already immunocompromised patient populations. This may also give further evidence to having ongoing and continuing collaboration between Dermatology and Medical Oncology for any patients presenting with a new rash undergoing chemotherapy treatments.

Thymoquinone-PLGA-PVA Nanoparticles Ameliorate Bleomycin-Induced Pulmonary Fibrosis in Rats via Regulation of Inflammatory Cytokines and iNOS Signaling

Pulmonary fibrosis is considered one of the most chronic interstitial illnesses which are not easily treated. thymoquinone's (TQ) benefits are still partly problematic due to poor water solubility; therefore, it was loaded onto PLGA-PVA carriers. This study aimed to evaluate the potential effect of TQ-PLGA-PVA nanoparticles (TQ-PLGA-PVA-NPs) on pulmonary fibrosis induced by bleomycin in albino rats. Forty male rats were randomized into four groups. The first group served as the control group; the second and the third groups received bleomycin intratracheally, whereas the third group received TQ-PLGA-PVA-NPs after 4 weeks from bleomycin administration. The fourth group was administrated TQ-PLGA-PVA-NPs alone. The designed nanoparticles appeared around 20 nm size (10-30 nm), had a spherical shape, and had 80% encapsulation efficiency. The histological examination of rats simultaneously treated with TQ-PLGA-PVA-NPs and bleomycin revealed reduction in the thickness of the alveolar septa and improvement of the other lung structures, with the presence of lymphocytes admixed with exfoliated epithelium in a few lumina remaining. Ultrastructural findings revealed marked collagenolysis and the release of nanoparticles from ruptured pneumocytes within the alveolar septa after 14 days from TQ-PLGA-PVA-NPs administration. Very active pneumocyte types II were seen in the TQ-PLGA-PVANP group. Additionally, immunohistochemical expression of inducible nitric oxide (iNOS) and estimation of inflammatory cytokines in lung tissues including interleukin 10 (IL 10) and transforming growth factor-beta (TGF-β1) confirmed the antioxidant and anti-inflammatory effects of TQ-PLGA-PVANPs. The study concluded that TQ-PLGA-PVA-NPs could attenuate the bleomycin-induced pulmonary fibrosis, through the inhibition of lung inflammation and the suppression of bleomycin- induced oxidative stress.