Functionalization of poly(3-hydroxybutyrate) with different thiol compounds inhibits MDM2-p53 interactions in MCF7 cells

Characterization of Poly(3-hydroxybutyrate) (P3HB) from Alternative, Scalable (Waste) Feedstocks

Bioplastics hold significant promise in replacing conventional plastic materials, linked to various serious issues such as fossil resource consumption, microplastic formation, non-degradability, and limited end-of-life options. Among bioplastics, polyhydroxyalkanoates (PHA) emerge as an intriguing class, with poly(3-hydroxybutyrate) (P3HB) being the most utilized. The extensive application of P3HB encounters a challenge due to its high production costs, prompting the investigation of sustainable alternatives, including the utilization of waste and new production routes involving CO2 and CH4. This study provides a valuable comparison of two P3HBs synthesized through distinct routes: one via cyanobacteria (Synechocystis sp. PCC 6714) for photoautotrophic production and the other via methanotrophic bacteria (Methylocystis sp. GB 25) for chemoautotrophic growth. This research evaluates the thermal and mechanical properties, including the aging effect over 21 days, demonstrating that both P3HBs are comparable, exhibiting physical properties similar to standard P3HBs. The results highlight the promising potential of P3HBs obtained through alternative routes as biomaterials, thereby contributing to the transition toward more sustainable alternatives to fossil polymers.

Ocimum basilicum Essential Oil Modulates Hematotoxicity, Oxidative Stress, DNA Damage, and Cell Cycle Arrest Induced by β-cyfluthrin in Rat Liver

Pesticides are used in large quantities infrequently, resulting in environmental damage and health issues. The goal of the current study was to explore the ameliorating effect of Ocimum basilicum (Basil) leaves essential oil versus the harmful effects of β-cyfluthrin in rat liver. Male Wistar rats were classified at random into four groups; negative control (corn oil), basil leaves essential oil (BEO, 3 ml/kg), β-cyfluthrin (positive control) (β-Cyf; 15 mg/kg BW, 1/25 LD50), and BEO plus β-Cyf, respectively. The rats were given their doses orally every day for a month. Results revealed that BEO yielded 6.32 mg/g with 33 identified components, representing 97% of the total oil. BEO implicated a considerable level of total phenolic contents, DPPH radical scavenging capacity, ABTS activity, and FRAP. The treatment of β-Cyf dramatically elevated lipid peroxidation (TBARS and H2O2) (LPO), protein oxidation (PC, AOPP, and HYP), and considerably reduced enzymatic (SOD, CAT, GPx, GR, and GST) and non-enzymatic (GSH) antioxidants. After β-Cyf treatment, hematological parameters, body and liver weights, enzyme activity (AST, ALT, ALP, and LDH), as well as protein, albumin, globulin, and total bilirubin levels were all considerably affected. Furthermore, β-Cyf increased the expression of pro-inflammatory genes (TNF-α, IL-6) as well as DNA damage and cell cycle arrest in the G0/G1 phase and decreased the number of cells in S and G2/M phase of liver cells. Moreover, rats given BEO then intoxicated with β-Cyf showed substantial changes in the majority of the parameters tested. Finally, BEO was shown to have high antioxidant efficacy in combating β-Cyf toxicity because of its high phenolic content.

Therapeutic potential of camel milk exosomes against HepaRG cells with potent apoptotic, anti-inflammatory, and anti-angiogenesis effects for colostrum exosomes

This study aimed to evaluate and compare the therapeutic effect of camel milk exosomes derived from colostrum, early, mid, and late lactation periods on liver cancer HepaRG cells. These exosomes showed cytotoxicity on HepaRG while being safer on normal human liver THLE-2 cells. Among the four different isolated exosome groups, exosomes isolated from colostrum exhibited the highest apoptotic potential on HepaRG as indicated by highest DNA damage and upregulated expression of Bax and caspase3 expression, but with lowest Bcl2 expression. HepaRG-treated with colostrum-derived exosomes also exhibited the lowest expression of inflammation-related genes (TNFα, NFkB, TGFβ1, and Cox2) and the angiogenesis-related gene VEGF. Colostrum-derived exosomes had significantly higher expression of lactoferrin and kappa casein than other milk-derived exosomes. These results indicate that colostrum-derived exosomes have a more potent anti-cancer effect on HepaRG cells than exosomes derived from the early, mid, and lat lactation periods. This effect could be mediated through induction of apoptosis and inhibition of inflammation and angiogenesis. Therefore, these exosomes could be used as safe adjuvants/carriers to deliver chemotherapeutics and to potentiate their anticancer effect on liver cancer cells.

Panax ginseng modulates oxidative stress, DNA damage, apoptosis, and inflammations induced by silicon dioxide nanoparticles in rats

Silicon dioxide nanoparticles (SiO₂ NPs) are extensively used in cosmetics, food, and drug delivery. The main mechanism of SiO₂ NPs toxicities depends on oxidative stress. Ginseng (Panax ginseng Meyer) is used in various medicinal applications because of its antioxidant efficiency. Therefore, the present study was carried out to investigate the possible combated role of ginseng against SiO₂ NPs toxicity in rat liver. Thirty-five male rats (160-180 g) were allocated into five groups of seven rats each, randomly. The first group was used as a control while groups 2, 3, 4, and 5 were treated orally with ginseng (Gin; 75 mg/kg, 1/10 LD₅₀ ), SiO₂ NPs, (200 mg/kg, 1/10 LD₅₀ ), Gin + SiO₂ NPs (protection group), and SiO₂ NPs + Gin (therapeutic group) for 5 weeks, respectively. Treatment with SiO₂ NPs increased lipid peroxidation, liver function enzymes, and decreased antioxidant enzymes (SOD, CAT, GPx, GST) activity and non-enzymatic antioxidant (GSH) level. SiO₂ NPs administration motivated liver apoptosis as revealed by the upregulation of the apoptotic genes, Bcl2-associated x protein (Bax), and Beclin 1 and downregulation of the anti-apoptotic gene, B-cell lymphoma 2 (Bcl2) as well as increase in DNA damage. Also, SiO₂ NPs administration caused inflammation as indicated by upregulation of the inflammation-related genes (interleukin 1 beta [IL1β], tumor necrosis factor-alpha [TNFα], nuclear factor kappa B [NFκB], cyclooxygenase 2 [Cox2], transforming growth factor-beta 1 [TGFβ1]) as well as cell cycle arrest in the G0/G1 phase of liver cells. Moreover, histopathological examination proved the biochemical and molecular perturbations occurred due to SiO₂ NPs toxicity. On the other hand, ginseng caused a significant modulation on the deleterious effects induced by SiO₂ NPs in rat liver. In conclusion, ginseng has a potent preventive effect than the therapeutic one and might be used in the treatment of SiO₂ NPs hepatotoxicity.

Poly(3-hydroxybutyrate)/poly(amine)-coated nickel oxide nanoparticles for norfloxacin delivery: antibacterial and cytotoxicity efficiency

Sustained release dosage forms enable prolonged and continuous release of a drug in the gastrointestinal tract for medication characterized by a short half lifetime. In this study, the effect of blending polyamine on poly(3-hydroxybutyrate) (PHB) as a carrier for norfloxacin (NF) was studied. The prepared blend was mixed with different amounts of NiO nanoparticles and characterized using FTIR analysis, X-ray diffraction analysis, thermogravimetric analysis, dynamic light scattering, transmission electron microscopy and scanning electron microscopy. It was found that the drug released from the nanocomposite has a slow rate in comparison with NiO, PHB, and PHB/polyamine blend. The highest ratio of NiO content to the matrix (highest NF loading), leads to a slower rate of drug release. The release from the nanocomposites showed a faster rate at pH = 2 than that at pH = 7.4. The mechanisms of NF adsorption and release were studied on PHB/polyamine-3% NiO nanocomposite. In addition, the antimicrobial efficacy of nanocomposites loaded with the drug was determined and compared with the free drug. Inclusion of NiO into PHB/polyamine showed a higher efficacy against Streptococcus pyogenes and Pseudomonas aeruginosa than the free NF. Moreover, the cytotoxicity of PHB/polyamine-3% NiO against HePG-2 cells was investigated and compared with PHB and PHB/polyamine loaded with the drug. The most efficient IC50 was found for NF@PHB/polyamine-3% NiO (29.67 μg mL-1). No effect on cell proliferation against the normal human cell line (WISH) was observed and IC50 was detected to be 44.95 and 70 μg mL-1 for NiO nanoparticles and the PHB/polyamine-3% NiO nanocomposite, respectively indicating a selectivity of action towards tumor cells coupled with a lack of cytotoxicity towards normal cells.

Therapeutic effect of Arthrocnemum machrostachyum methanolic extract on Ehrlich solid tumor in mice

Background

The anti-cancer effect of the halophyte Arthrocnemum indicum, a member of Arthrocnemum family of salt-tolerant plants, was evaluated against colorectal cancer cell, CaCo2. However, the anti-cancer effect of another halophyte Arthrocnemum machrostachyum was not investigated yet. Herein, the anticancer effect of A. machrostachyum methanolic extract (AME) was evaluated against Ehrlich solid tumor (EST) in mice and the potential mechanism of action was also studied.

Methods

Male Swiss albino mice (n = 28) were randomly divided into 4 groups (n = 7/group). Group 1 (negative control group); group 2 (EST) injected intramuscularly by 0.2 mL Ehrlich ascitic carcinoma (2 × 10⁶ cells); and groups 3 and 4 injected intratumorally with AME (180 and 360 mg/kg body weight, respectively) at D12 trice weekly for 2 weeks. Gene expression, protein expression, DNA damage, and TNFa level in tumors were determined by real-time PCR, western blot, comet assay, and Elisa, respectively.

Results

Treatment with AME induced anti-tumor effects against EST as indicated by 1) notable reduction in tumor size; 2) elevation in tissue necrosis and apoptosis, as confirmed histologically; 3) increased DNA fragmentation; 4) decreased expression of the apoptotic genes (p53, Bax and caspase 3), and increased expression of the anti-apoptotic marker Bcl2; 5) significantly upregulated cell cycle regulatory genes Cdc2 and connexin26, and; 6) decreased TNFa levels in tumor tissues. Interestingly, a high dose of AME exhibited a more potent anti-tumor effect against EST.

Conclusion

These findings indicate that AME has a potent antitumor effect against EST and could be used as an adjuvant to anticancer drugs to combat tumor, but after application of further confirmatory clinical trials.

The Microbial Production of Polyhydroxyalkanoates from Waste Polystyrene Fragments Attained Using Oxidative Degradation

Excessive levels of plastic waste in our oceans and landfills indicate that there is an abundance of potential carbon sources with huge economic value being neglected. These waste plastics, through biological fermentation, could offer alternatives to traditional petrol-based plastics. Polyhydroxyalkanoates (PHAs) are a group of plastics produced by some strains of bacteria that could be part of a new generation of polyester materials that are biodegradable, biocompatible, and, most importantly, non-toxic if discarded. This study introduces the use of prodegraded high impact and general polystyrene (PS0). Polystyrene is commonly used in disposable cutlery, CD cases, trays, and packaging. Despite these applications, some forms of polystyrene PS remain financially and environmentally expensive to send to landfills. The prodegraded PS0 waste plastics used were broken down at varied high temperatures while exposed to ozone. These variables produced PS flakes (PS1⁻3) and a powder (PS4) with individual acid numbers. Consequently, after fermentation, different PHAs and amounts of biomass were produced. The bacterial strain, Cupriavidus necator H16, was selected for this study due to its well-documented genetic profile, stability, robustness, and ability to produce PHAs at relatively low temperatures. The accumulation of PHAs varied from 39% for prodegraded PS0 in nitrogen rich media to 48% (w/w) of dry biomass with the treated PS. The polymers extracted from biomass were analyzed using nuclear magnetic resonance (NMR) and electrospray ionization tandem mass spectrometry (ESI-MS/MS) to assess their molecular structure and properties. In conclusion, the PS0⁻3 specimens were shown to be the most promising carbon sources for PHA biosynthesis; with 3-hydroxybutyrate and up to 12 mol % of 3-hydroxyvalerate and 3-hydroxyhexanoate co-monomeric units generated.