Lead Nitrate Induces Inflammation and Apoptosis in Rat Lungs Through the Activation of NF-κB and AhR Signaling Pathways.

Lead (Pb) is one of the most frequent hazardous air contaminants, where the lungs are particularly vulnerable to its toxicity. However, the Pb distribution and its impact on lung inflammation/apoptosis and particularly the involvement of nuclear factor kappa B (NF-κB) and aryl hydrocarbon receptor (AhR) signaling pathways in Pb-induced lung toxicity have not yet been fully investigated. Adult male Wistar albino rats were exposed to Pb nitrate 25, 50, and 100 mg/kg b.w. orally for 3 days. The histopathological changes of several rat organs were analyzed using hematoxylin and eosin staining. The concentrations of Pb ion in different organ tissues were quantified using inductive coupled plasma mass spectrometry, while gas chromatography-mass spectrometry was used to identify organic compounds. The changes in the mRNA and protein expression levels of inflammatory and apoptotic genes in response to Pb exposure were quantified by using RT-PCR and Western blot analyses, respectively. Treatment of rats with Pb for three consecutive days significantly increased the accumulation of Pb in lung tissues causing severe interstitial inflammation. Pb treatment also increased the percentage of lung apoptotic cells and modulated apoptotic genes (Bc2, p53, and TGF-α), inflammatory markers (IL-4, IL-10, TNF-α), and oxidative stress biomarkers (iNOS, CYP1A1, EphX) in rat lung tissues. These effects were associated with a significant increase in organic compounds, such as 3-nitrotyrosine and myeloperoxidase, and some inorganic elements, such as selenium. Importantly, the Pb-induced lung inflammation and apoptosis were associated with a proportional increase in the expression of NF-κB and AhR mRNAs and proteins. These findings clearly show that Pb induces severe inflammation and apoptosis in rat lungs and suggest that NF-κB and AhR may play a role in Pb-induced lung toxicity.

Diosmin Alleviates Doxorubicin-Induced Liver Injury via Modulation of Oxidative Stress-Mediated Hepatic Inflammation and Apoptosis via NfkB and MAPK Pathway: A Preclinical Study.

Hepatotoxicity caused by chemotherapeutic drugs (e.g., doxorubicin) is of critical concern in cancer therapy. This study focused on investigating the modulatory effects of diosmin against doxorubicin-induced hepatotoxicity in Male Wistar rats. Male Wistar rats were randomly divided into four groups: Group I was served as control, Group II was treated with doxorubicin (20 mg/kg, intraperitoneal, i.p.), Group III was treated with a combination of doxorubicin and low-dose diosmin (100 mg/kg orally), and Group IV was treated with a combination of doxorubicin and high-dose diosmin (200 mg/kg orally) supplementation. A single dose of doxorubicin (i.p.) caused hepatic impairment, as shown by increases in the concentrations of serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. Doxorubicin produced histological abnormalities in the liver. In addition, a single injection of doxorubicin increased lipid peroxidation and reduced glutathione, catalase, and superoxide dismutase (SOD) levels. Importantly, pre-treatment with diosmin restored hepatic antioxidant factors and serum enzymatic activities and reduced the inflammatory and apoptotic-mediated proteins and genes. These findings demonstrate that diosmin has a protective effect against doxorubicin-induced hepatotoxicity.

Molecular mechanisms of cardiotoxicity of gefitinib in vivo and in vitro rat cardiomyocyte: Role of apoptosis and oxidative stress.

Gefitinib (GEF) is a multi-targeted tyrosine kinase inhibitor with anti-cancer properties, yet few cases of cardiotoxicity has been reported as a significant side effect associated with GEF treatment. The main purpose of this study was to investigate the potential cardiotoxic effect of GEF and the possible mechanisms involved using in vivo and in vitro rat cardiomyocyte model. Treatment of rat cardiomyocyte H9c2 cell line with GEF (0, 1, 5, and 10µM) caused cardiomyocyte death and upregulation of hypertrophic gene markers, such as brain natriuretic peptides (BNP) and Beta-myosin heavy chain (ß-MHC) in a concentration-dependent manner at the mRNA and protein levels associated with an increase in the percentage of hypertrophied cardiac cells. Mechanistically, GEF treatment caused proportional and concentration-dependent increases in the mRNA and protein expression levels of apoptotic markers caspase-3 and p53 which was accompanied with marked increases in the percentage of H9c2 cells underwent apoptosis/necrosis as compared to control. In addition, oxidative stress marker (heme oxygenase-1, HO-1) and the formation of reactive oxygen species were increased in response to GEF treatment. At the in vivo level, treatment of Wistar albino rats for 21days with GEF (20 and 30mg/kg) significantly increased the cardiac enzymes (CK, CKmb, and LDH) levels associated with histopathological changes indicative of cardiotoxicity. Similarly, in vivo GEF treatment increased the mRNA and protein levels of BNP and ß-MHC whereas inhibited the antihypertrophoic gene (α-MHC) associated with increased the percentage of hypertrophied cells. Furthermore, the mRNA and protein expression levels of caspase-3, p53, and HO-1 genes and the percentage of apoptotic cells were significantly increased by GEF treatment, which was more pronounced at the 30mg/kg dose. In conclusion, GEF induces cardiotoxicity and cardiac hypertrophy in vivo and in vitro rat model through cardiac apoptotic cell death and oxidative stress pathways.