Protective effects of natural compounds against paraquat-induced pulmonary toxicity: the role of the Nrf2/ARE signaling pathway.

Paraquat (PQ) is a toxic herbicide to humans. Once absorbed, it accumulates in the lungs. PQ has been well documented that the generation of reactive oxygen species (ROS) is the main mechanism of its toxicity. Oxidative damage of PQ in lungs is represented as generation of cytotoxic and fibrotic mediators, interruption of epithelial and endothelial barriers, and inflammatory cell infiltration. No effective treatment for PQ toxicity is currently available. Several studies have shown that natural compounds (NCs) have the potential to alleviate PQ-induced pulmonary toxicity, due to their antioxidant and anti-inflammatory effects. NCs function as protective agents through stimulation of nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathways. Elevation of Nrf2 levels leads to the expression of its downstream enzymes such as SOD, CAT, and HO-1. The hypothesized role of the Nrf2/ARE signaling pathway as the protective mechanism of NCs against PQ-induced pulmonary toxicity is reviewed.

Antimicrobial and cytotoxic naphthoquinones from microbial origin: An updated review.

Naphthoquinones (NQs) are small molecules bearing two carbonyl groups. They have been the subject of much research due to their significant biological activities such as antiproliferative, antimicrobial, anti-inflammatory, antioxidant, and antimalarial effects. NQs are produced mainly by bacteria, fungi and higher plants. Among them, microorganisms are a treasure of NQs with diverse skeletons and pharmacological properties. The purpose of the present study is to provide a comprehensive update on the structural diversity and biological activities of 91 microbial naphthoquinones isolated from 2015 to 2022, with a special focus on antimicrobial and cytotoxic activities. During this period, potent cytotoxic NQs such as naphthablin B (46) and hygrocin C (30) against HeLa (IC50=0.23 µg/ml) and MDA-MB-431 (IC50=0.5 µg/ml) cell lines was reported, respectively. In addition, rubromycin CA1 (39), exhibited strong antibacterial activity against Staphylococcus aureus (MIC of 0.2 µg/ml). As importance bioactive compounds, NQs may open new horizon for treatment of cancer and drug resistant bacteria. As such, it is hoped that this review article may stimulates further research into the isolation of further NQs from microbial, and other sources as well as the screening of such compounds for biological activity and beneficial uses.

Probabilistic carcinogenic and non-carcinogenic risk assessment of heavy metal ingestion through consumption of different walnut cultivars: An Iranian study.

The heavy metal levels in six walnut cultivars from five geographical zones of Iran were measured. An assessment of risks was conducted by calculating the Target Hazard Quotient (THQ) and Incremental Lifetime Cancer Risk (ILCR) by use of the Monte Carlo simulation method. The highest amounts of As and Pb were reported in Farouj samples. Also, the highest levels of Cr, Zn, Cu and Mn were determined in samples collected from Tuyserkan. Accordingly, 50th and 95th ILCRs for general population due to consumption of walnut were 1.03 × 10-4 and 3.11 × 10-4 (for As), 4.10 × 10-6 and 1.1 × 10-5 (for Cr) and 4.71 × 10-9 and 1.05 × 10-8 (for Pb), respectively. In addition, the 50th and 95th centiles of the HIs for walnut ingestion by Iranians were 1.02 and 2.05, respectively, indicating a minor chance of non-cancer effects. Based on the calculated 95% ILCR, dietary exposure to As through the consumption of walnut poses a risk to Iranian consumer health. However, ILCR values of other heavy metals (HMs) were in acceptable ranges (ILCR < 1 × 10-4), representing no toxicological concern for consumers. The most significantly influential parameters were determined by sensitivity analysis during the MCS. According to THQ and ILCR methods, concentration was the most sensitive parameters. For THQ method the concentration effects were ranged from 72.4 to 85.1%. Moreover, for ILCR method the effects of concentration in As, Cr, and Pb were 87.1, 79.1 and 83.54%, respectively.

Determination of 17ß-estradiol in commercial pasteurized and sterilized milk samples in Mashhad, Iran.

Due to nutritional facts of milk in human life, the quality assessment of dairy products is of the utmost importance. The aim of the current study was to determine the 17ß-estradiol level in commercial pasteurized and sterilized milk brands in Mashhad, Iran. In this regard, 160 samples including 80 pasteurized (40 high-fat and 40 low-fat) and 80 sterilized milk (40 high-fat and 40 low-fat) of widely used brands from different supermarkets were collected. The mean level of 17ß-estradiol was 8.2 ± 0.59 pg/ml. The mean amount of estradiol was found to be 7.6 ± 0.47, 7.9 ± 0.45, 8.6 ± 0.63, and 8.9 ± 0.54 pg/ml for the low-fat pasteurized, low-fat sterilized, high-fat pasteurized and high-fat sterilized milk, respectively. There was no significant difference between the amount of estradiol in pasteurized and sterilized milk. As expected, the level of estradiol was statistically higher in high fat milks than that of low-fat milks. Considering the levels of 17ß-estradiol measured here and the maximum permissible daily level of external estradiol entered to body through edible products recommended by EU and CAC (3.5 µg), at least in the short term, there will be no remarkable impact on the endocrine system. However, judging the long-term effects of using these products is not easy and simple at all, as cancers develop during a long period of time and has a multifactorial etiology.

Polycyclic aromatic hydrocarbons in infant formulae, follow-on formulae, and baby foods in Iran: An assessment of risk.

Twenty-seven samples of infant formulae and follow-on formulae and fifteen samples of baby food from Iranian markets were analyzed for concentrations of four polycyclic aromatic hydrocarbons (PAH4) determined by use of gas chromatography coupled to mass spectrophotometry. An assessment of risks posed to infants and toddlers was conducted by calculating the margin of exposure and incremental lifetime cancer risk (ILCR) by use of the Monte Carlo Simulation Method. Benzo (a) anthracene, was not detected in any of the samples, while approximately 64.3% samples contained detectable amounts of benzo (a) pyrene, while chrysene was observed in three samples and benzo (b) fluoranthene was detected in one sample. One of the samples contained 1.43 µg PAH4/kg, which was greater than the maximum tolerable limit (MTL; 1 µg/kg) stated in Commission Regulation (EU) 2015/1125. Accordingly, the 95% ILCRs in the infants/toddlers due to ingestion of milk powder and baby foods were determined to be 1.3 × 10-6 and 7.3 × 10-7, respectively. Also, the 95th centiles of the MOEs, due to ingesting milk powder or baby foods by infants/toddlers were estimated to be 3.6 × 104 and 7.2 × 104, respectively. In Iran, infants and toddlers are not at serious health risk (MOE ≥ 1 × 104 and ILCR < 1 × 10-4).