Lead is harmful for human health and animals. Proanthocyanidins (PCs), a natural antioxidant, possess a broad spectrum of pharmacological and medicinal properties. However, its protective effects against lead-induced liver damage have not been clarified. This study was aimed to evaluate the protective effect of PCs on the hepatotoxicity of male Kunming mice induced by chronic lead exposure. A total of 70 healthy male Kunming mice were averagely divided into four groups: control group, i.e., the group exposed to lead, the group treated with PCs, and the group co-treated with lead and PCs. The mice exposed to lead were given water containing 0.2% lead acetate. Mice treated in the PCs and PCs lead co-treated groups were given PC (100 mg/kg) in 0.9% saline by oral gavage. Lead exposure caused a significant elevation in the liver function parameters, lead level, lipid peroxidation, and inhibition of antioxidant enzyme activities. The induction of oxidative stress and histological alterations in the liver were minimized by co-treatment with PCs. Meanwhile, the number of Transferase-Mediated Deoxyuridine Triphosphate-Biotin Nick End Labeling (TUNEL)-positive cells was significantly reduced in the PCs/lead co-treated group compared to the lead group. In addition, the lead group showed an increase in the expression level of Bax, while the expression of Bcl-2 was decreased. Furthermore, the lead group showed an increase in the expression level of endoplasmic reticulum (ER) stress-related genes and protein (GRP78 and CHOP). Co-treated with PCs significantly reversed these expressions in the liver. PCs were, therefore, demonstrated to have protective, antioxidant, and anti-ER stress and anti-apoptotic activities in liver damage caused by chronic lead exposure in the Kunming mouse. This may be due to the ability of PCs to enhance the ability of liver tissue to protect against oxidative stress via the Nrf2/ARE signaling pathway, resulting in decreasing ER stress and apoptosis of liver tissue.
Expansins, cell-wall loosening proteins, play an important role in plant growth and development and abiotic stress tolerance. Ammopiptanthus nanus (A. nanus) is an important plant to study to understand stress resistance in forestry. In our previous study, two α-type expansins from A. nanus were cloned and named AnEXPA1 and AnEXPA2. In this study, we found that they responded to different abiotic stress and hormone signals. It suggests that they may play different roles in response to abiotic stress. Their promoters show some of the same element responses to abiotic stress and hormones, but some special elements were identified between the expansins that could be essential for their expression. In order to further testify the reliability of the above results, we conducted an analysis of β-glucuronidase (GUS) dyeing. The analysis showed that AnEXPA1 was only induced by cold stress, whereas AnEXPA2 responded to hormone induction. AnEXPA1 and AnEXPA2 transgenic Arabidopsis plants showed better tolerance to cold and drought stresses. Moreover, the ability to scavenge reactive oxygen species (ROS) was significantly improved in the transgenic plants, and expansin activity was enhanced. These results suggested that AnEXPA1 and AnEXPA2 play an important role in the response to abiotic stress. Our research contributes to a better understanding of the regulatory network of expansins and may benefit agricultural production.
A series of novel thioether andrographolide derivatives were synthesized by incorporating various aromatic (or heteroaromatic) substituents into C-12 or 14-OH. A total of 38 andrographolide derivatives were prepared and evaluated for their in vitro inhibitory activity against cancer cells. All the derivatives exhibited better activity against prostate cancer cells (PC-3) than the parent compound. Among these, compounds 6a, 8, 9, 17, 19, 31, and 32 demonstrated good activity. These compounds were further evaluated for their anticancer activities against other cancer cell lines including MCF-7, MDA-MB-231, and A549. Compounds 31 and 32 showed excellent activity against MCF-7 with an IC50 value of 0.7 and 0.6 μM, respectively. The absolute configuration of 15a was determined via single-crystal X-ray diffraction. The activity of 6a (12S), which was the precursor of 15a, was better than that of the diastereoisomer 6b (12R). Moreover, the preliminary structure–activity relationship has been summarized. The results obtained herein are very important for further optimization of andrographolide.
Spider silk protein has attracted much attention on account of its excellent mechanical properties, biodegradability, and biocompatibility. As the main protein component of spider silk, spidroin plays important role in spider spinning under natural circumstances and biomaterial application in medicine as well. Compare to the native spidroin which has a large molecular weight (>300 kDa) with highly repeat glycine and polyalanine regions, the recombinant spidroin was maintained the core amino motifs and much easier to collect. Here, we reviewed the application of recombinant spider silk protein eADF4(C16), major ampullate spidroin (MaSp), minor ampullate spidroin (MiSp), and the derivatives of recombinant spider silk protein in drug delivery system. Moreover, we also reviewed the application of spider silk protein in the field of alternative materials, repairing materials, wound dressing, surgical sutures along with advances in recombinant spider silk protein.