Pharmacological approaches for targeting lysosomes to induce ferroptotic cell death in cancer.

Lysosomes are crucial organelles responsible for the degradation of cytosolic materials and bulky organelles, thereby facilitating nutrient recycling and cell survival. However, lysosome also acts as an executioner of cell death, including ferroptosis, a distinctive form of regulated cell death that hinges on iron-dependent phospholipid peroxidation. The initiation of ferroptosis necessitates three key components: substrates (membrane phospholipids enriched with polyunsaturated fatty acids), triggers (redox-active irons), and compromised defence mechanisms (GPX4-dependent and -independent antioxidant systems). Notably, iron assumes a pivotal role in ferroptotic cell death, particularly in the context of cancer, where iron and oncogenic signaling pathways reciprocally reinforce each other. Given the lysosomes' central role in iron metabolism, various strategies have been devised to harness lysosome-mediated iron metabolism to induce ferroptosis. These include the re-mobilization of iron from intracellular storage sites such as ferritin complex and mitochondria through ferritinophagy and mitophagy, respectively. Additionally, transcriptional regulation of lysosomal and autophagy genes by TFEB enhances lysosomal function. Moreover, the induction of lysosomal iron overload can lead to lysosomal membrane permeabilization and subsequent cell death. Extensive screening and individually studies have explored pharmacological interventions using clinically available drugs and phytochemical agents. Furthermore, a drug delivery system involving ferritin-coated nanoparticles has been specifically tailored to target cancer cells overexpressing TFRC. With the rapid advancements in understandings the mechanistic underpinnings of ferroptosis and iron metabolism, it is increasingly evident that lysosomes represent a promising target for inducing ferroptosis and combating cancer.

Gastrodin relieves cognitive impairment by regulating autophagy via PI3K/AKT signaling pathway in vascular dementia.

Vascular dementia (VaD), the second most common type of dementia, is attributed to lower cerebral blood flow. To date, there is still no available clinical treatment for VaD. The phenolic glucoside gastrodin (GAS) is known for its neuroprotective effects, but the role and mechanisms of action on VD remains unclear. In this study, we aim to investigate the neuroprotective role and underlying mechanisms of GAS on chronic cerebral hypoperfusion (CCH)-mediated VaD rats and hypoxia-induced injury of HT22 cells. The study showed that GAS relieved learning and memory deficits, ameliorated hippocampus histological lesions in VaD rats. Additionally, GAS down-regulated LC3II/I, Beclin-1 levels and up-regulated P62 level in VaD rats and hypoxia-injured HT22 cells. Notably, GAS rescued the phosphorylation of PI3K/AKT pathway-related proteins expression, which regulates autophagy. Mechanistic studies verify that YP-740, a PI3K agonist, significantly resulted in inhibition of excessive autophagy and apoptosis with no significant differences were observed in the YP-740 and GAS co-treatment. Meantime, we found that LY294002, a PI3K inhibitor, substantially abolished GAS-mediated neuroprotection. These results revealed that the effects of GAS on VaD are related to stimulating PI3K/AKT pathway-mediated autophagy, suggesting a potentially beneficial therapeutic strategy for VaD.

Characterization and determination of antioxidant components in the leaves of Camellia chrysantha (Hu) Tuyama based on composition-activity relationship approach.

Camellia chrysantha (Hu) Tuyama (CCT), an ornamental plant possessing antioxidant activity, has been infused as tea and drank for its health benefits. The antioxidant components in CCT, however, had not been clearly characterized. To quickly identify the antioxidant constituents of CCT, a composition-activity relationship strategy based on ultra high-pressure liquid chromatography coupled with linear ion trap hybrid orbitrap mass spectrometry and orthogonal partial least-squares method has been applied. As a result, 16 variables were found to make significant contributions to the 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. Six of them were identified as catechin (1), epicatechin (5), vitexin (8), isovitexin (10), quercetin-7-O-ß-D-glucopyranoside (12) and kaempferol (16). The strength of 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity was found to be 12 > 1 > 5 > 16 > 8 > 10 by validation test. Meanwhile, a liquid chromatography-electrospray ionization-mass spectrometry method was established for quantitative determination of six marker compounds in CCT samples from different preparations. The validation of the method, including linearity, sensitivity (limitation of detection and limitation of quantification), repeatability, precision, stability, and recoveries, was carried out and demonstrated to meet the requirements of quantitative analysis. This is the first report on the comprehensive characterization and determination of chemical constituents in CCT by ultra high-pressure liquid chromatography coupled with linear ion trap hybrid orbitrap mass spectrometry. The results indicate that the composition-activity relationship approach may be a useful method for the discovery of active constituents in natural plants and the quality control of medicinal herbs.

Association between the c.3751G>a genetic variant of MDR1 and hepatocellular carcinoma risk in a Chinese Han population.

The objective of this study was to evaluate the influence of a genetic variant in the multidrug resistance 1 gene (MDR1) on hepatocellular carcinoma (HCC) risk. This case-control study was conducted in a Chinese population of 645 HCC cases and 658 cancer-free controls. The genotype of the c.3751G>A genetic variant in the MDR1 gene was investigated by created restriction site-polymerase chain reaction (CRS-PCR) and DNA sequencing methods. Our data demonstrated significantly differences detected in the allelic and genotypic frequencies between HCC cases and those of cancer-free controls. Association analyses indicated that there were statistically increased risk of HCC in the homozygote comparison (AA versus (vs.) GG: OR = 2.22, 95% CI 1.51-3.27, χ(2) = 16.90, P < 0.001), dominant model (AA/GA vs. GG: OR = 1.25, 95% CI 1.00-1.55, χ(2) = 3.98, P = 0.046), recessive model (AA vs. GA/GG: OR = 2.14, 95% CI 1.47-3.09, χ(2) = 16.68, P < 0.001) and allele comparison (A vs. G: OR = 1.33, 95% CI 1.13-1.57, χ(2) = 11.66, P = 0.001). The allele-A and genotype-AA may contribute to HCC susceptibility. These preliminary findings suggest that the c.3751G>A genetic variant in the MDR1 gene is potentially related to HCC susceptibility in a Chinese Han population, and might be used as a molecular marker for evaluating HCC susceptibility.

Enhancement of invasion of hepatocellular carcinoma cells through lysophosphatidic acid receptor.

OBJECTIVES: Lysophosphatidic acid (LPA) is a bioactive lipid mediator involved in tumour progression, cell invasion and metastasis. The mechanism of action of LPA in the invasive and metastatic capacity of human hepatocellular carcinoma (HCC) is not fully understood. This study investigated the effects of LPA on HCC cell invasion and induction of matrix metalloproteinase (MMP) -2 and -9. METHODS: LPA receptor levels in HCC cell lines were detected by Western blot analysis; HCC cell invasion was analysed by the Transwell® system. The LPA receptor blocker Ki16425 was used to determine whether HCC cell invasion was LPA dependent. Expression of the MMP2 and MMP9 genes in HCC cells was determined by real-time quantitative reverse transcription-polymerase chain reaction (qPCR). RESULTS: LPA increased HCC cell invasion, which was LPA-receptor dependent. Real-time RT-qPCR showed that LPA increased MMP9, but not MMP2, expression in HCC cells. Pharmacological inhibition of LPA receptors with Ki16452 significantly attenuated LPA-induced HCC cell invasion. CONCLUSIONS: HCC invasiveness is facilitated by LPA and may be relevant to tumour progression. Thus, LPA receptors may be a potential therapeutic target for HCC.

[Protective effect of isoorientin on alcohol-induced hepatic fibrosis in rats].

OBJECTIVE: To observe the effect and mechanism of isoorientin from Gypsophila elegans on alcohol-induced hepatic fibrosis in rats. METHOD: ninety healthy male Wistar rats were randomly divided into six groups: the normal control group, the model control group, the colchicines group (positive control, 1.0 mg x kg(-1) x d(-1)), the high, middle and low-dose isoorientin groups (20, 50, 100 mg x kg(-1) x d(-1)). The normal control group received normal saline, while other groups received alcohol to cause hepatic fibrosis. After 24-weeks treatment, the alanine aminotransferase (ALT), aspartate aminotransferase (AST), Interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), hyaluronic acid (HA), laminin (LN), type III precollagen (PCIII), hydroxyproline (Hyp), Myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) were assayed according to the manufacturer's instructions, the alpha-SMA and TGF-beta1 were detected by western blotting, and the histopathological changes was observed by H&E staining. RESULT: Isoorientin could improve the liver function by decreasing the activity of ALT, AST, IL-6, TNF-alpha, MDA, MPO, HA, LN, PCIII and Hyp (P < 0.05), increasing the activity of SOD and GSH-Px (P < 0.05), and reducing the expression of alpha-SMA and TGF-beta1 (P < 0.05). In addition, the high and middle-dose isoorientin groups showed more remarkable effect CONCLUSION: Isoorientin from G. elegans can protect hepatic fibrosis induced by alcohol.

[Spiral computed tomography (CT) and magnetic resonance imaging (MRI) in assessment of the skull base encroachment in nasopharyngeal carcinoma].

BACKGROUND & OBJECTIVE: With the general using of computed tomography (CT) and magnetic resonance imaging (MRI), it is important to determine which method is more sensitive in detecting the skull base encroachment in clinic. This article was designed to investigate the diagnostic value of CT and MRI in detecting the skull base erosion in nasopharyngeal carcinoma patients. METHODS: Sixty-one cases pathologically proven as nasopharyngeal carcinoma were selected from August 1993 to September 2001. three-dimensional reconstruction with spiral CT thin slices scan were performed in 8 cases. CT scan was performed with Elscient CT Twin Flash; axial scan was parallel to the OM line routinely from soft palate to the suprasellar cistern. There were 13 cases with enhancement scan. MRI scan was performed by Philips T5-II super-conducting magnetic resonance imaging system (0.5T). The standard quadrature head coil was used. Routine axial, sagittal, and coronal image with SE sequences were obtained. Scanned field ranged from the soft palate to the suprasellar cistern. After plain scan, enhanced scan was performed in 55 of 61 cases. RESULTS: MRI discovered the skull base encroached more precisely than CT, 17 cases by CT and 26 cases by MRI, respectively. The early bone marrow infiltration was seen at clivus, basilar pterygoid, and basilar sphenoid in 6 cases by MRI scan while CT scan showed no abnormal lesion at these sites. In addition, MRI revealed nasopharyngeal carcinoma tissue infiltrated along the mandibular nerve (3 cases) while CT scan showed no change of these structures. CONCLUSION: Both CT and MRI can reveal that the tumor encroaches on the skull base by either destroying the bony structure or breaking through the natural foramen. MRI is more sensitive than CT in detecting the skull base encroachment. MRI could reveal the early infiltration of the bone marrow and tumor infiltration along the mandibular nerve. MRI confirms the dimension of nasopharyngeal carcinoma more precisely than CT. The three dimension reconstructional spiral CT was directer in discovering the dimension of the tumor.