Drug transportation is impeded by various barriers in the hypoxic solid tumor, resulting in compromised anticancer efficacy. Herein, a solid lipid monostearin (MS)-coated CaO2/MnO2 nanocarrier was designed to optimize doxorubicin (DOX) transportation comprehensively for chemotherapy enhancement. The MS shell of nanoparticles could be destroyed selectively by highly-expressed lipase within cancer cells, exposing water-sensitive cores to release DOX and produce O2. After the cancer cell death, the core-exposed nanoparticles could be further liberated and continue to react with water in the tumor extracellular matrix (ECM) and thoroughly release O2 and DOX, which exhibited cytotoxicity to neighboring cells. Small DOX molecules could readily diffuse through ECM, in which the collagen deposition was decreased by O2-mediated hypoxia-inducible factor-1 inhibition, leading to synergistically improved drug penetration. Concurrently, DOX-efflux-associated P-glycoprotein was also inhibited by O2, prolonging drug retention in cancer cells. Overall, the DOX transporting processes from nanoparticles to deep tumor cells including drug release, penetration, and retention were optimized comprehensively, which significantly boosted antitumor benefits.

In a previous clinical study, the moisture content in the stratum corneum of healthy Japanese women who consumed a beverage rich in oligomeric proanthocyanidins (OPCs) made from red wine extract was found to be higher than that in the control group. This finding suggested that OPCs can increase skin moisture content. In this study, we determined the expression level of aquaporin-3 (AQP3) in keratinocytes to elucidate the mechanism by which compounds in red wine grape increase moisture content in stratum corneum. Through in vitro studies, we confirmed that normal human epidermal keratinocytes (NHEK) incubated with red wine induced AQP3 expression. Furthermore, the supplementation of red wine fractions enriched in OPC was shown to increase AQP3 expression. Besides, the component of OPC-rich fractions that upregulated AQP3 expression was found to be a gallic acid (GA)-binding flavan-3-ol, particularly oligomeric compounds. We found that GA-binding OPC were able to upregulate AQP3 expression and that these compounds were enriched in red wine. Our findings might suggest that the mechanism of enhancement of moisture content in stratum corneum by red wine might be via the upregulation of AQP3 expression in the epidermal keratinocytes.

UNASSIGNED: Diabetes mellitus and pancreatic cancer are intimately related. Our previous studies showed that high levels of blood glucose promote epithelial-mesenchymal transition of pancreatic cancer. In this study, we evaluated the relationship between hyperglycemia and hypoxic tumor microenvironments.
UNASSIGNED: HIF-1α expression was evaluated by immunohistochemistry in clinical pancreatic cancer tissues with or without diabetes mellitus. Statistcal analysis was performed to explore the relationship between HIF-1α expression and pathological features of patients with pancreatic cancer. In vivo and in vitro models was established to detect whether a hyperglycemia environment could cause hypoxia in the pancreatic parenchyma and promote pancreatic cancer. In addition, we also tested the effect of HIF-1α siRNA on the high glucose-induced invasive and migratory abilities of BxPC-3 cells in culture.
UNASSIGNED: Our data showed that pancreatic cancer patients with diabetes had a higher level of HIF-1α expression as well as biliary duct invasion and larger tumor volumes than individuals in the euglycemic group. Diabetic nude mice treated with streptozotocin (STZ) exhibited larger tumors and were more likely to develop liver metastasis than control mice. Acinar cells of the pancreas in diabetic mice showed an obvious expansion of the endoplasmic reticulum and increased nuclear gaps as well as chromatin close to the cellular membrane in some acinar cells. The expression area for Hypoxyprobe-1 and HIF-1α in the diabetic orthotopic xenograft group was larger than that in the control group. The expression level of HIF-1α in the BxPC-3 cancer cell line increased in response to high glucose and CoCl2 concentrations. The high glucose-induced invasive ability, migratory capacity and MMP-9 expression were counter-balanced by siRNA specific to HIF-1α.
UNASSIGNED: Our results demonstrate that the association between hyperglycemia and poor prognosis can be attributed to microenvironment hypoxia in pancreatic cancer.

Hypoxia is beneficial for the differentiation of stem cells transplanted for myocardial injury, but mechanisms underlying this benefit remain unsolved. Here, we report the impact of hypoxia-induced Jagged1 expression in cardiomyocytes (CMs) for driving the differentiation of cardiac stem cells (CSCs). Forced hypoxia-inducible factor 1α (HIF-1α) expression and physical hypoxia (5% O2) treatment could induce Jagged1 expression in neonatal rat CMs. Pharmacological inhibition of HIF-1α by YC-1 attenuated hypoxia-promoted Jagged1 expression in CMs. An ERK inhibitor (PD98059), but not inhibitors of JNK (SP600125), Notch (DAPT), NF-κB (PTDC), JAK (AG490), or STAT3 (Stattic) suppressed hypoxia-induced Jagged1 protein expression in CMs. c-Kit+ CSCs isolated from neonatal rat hearts using a magnetic-activated cell sorting method expressed GATA4, SM22α or vWF, but not Nkx2.5 and cTnI. Moreover, 87.3% of freshly isolated CSCs displayed Notch1 receptor expression. Direct co-culture of CMs with BrdU-labeled CSCs enhanced CSCs differentiation, as evidenced by an increased number of BrdU+/Nkx2.5+ cells, while intermittent hypoxia for 21 days promoted co-culture-triggered differentiation of CSCs into CM-like cells. Notably, YC-1 and DAPT attenuated hypoxia-induced differentiation. Our results suggest that hypoxia induces Jagged1 expression in CMs primarily through ERK signaling, and facilitates early cardiac lineage differentiation of CSCs in CM/CSC co-cultures via HIF-1α/Jagged1/Notch signaling.

Angiopoietin-like protein 4 (ANGPTL4) is a lipoprotein lipase inhibitor that is involved in lipid metabolism and angiogenesis. Animal studies have suggested that the ANGPTL4 protein is modulated by the gut microbiota, possibly through increased concentrations of SCFA, such as C4, found in whole-fat milk or as a result of fermentation of inulin. This study investigated whether a standardised diet either high in fat content or supplemented with inulin powder would increase plasma ANGPTL4 in overweight men and whether this increase was mediated through a compositional change of the gut microbiota. The study had a crossover design with three arms, where participants were given a standardised isoenergetic diet supplemented with inulin powder, whole-fat milk or water (control). Plasma and urine samples were collected before and after each intervention period. Faecal samples and adipose tissue biopsies were collected after each intervention period. The study included twenty-one participants of whom eighteen completed the study. The dietary interventions did not change ANGPTL4 plasma concentration, nor was plasma ANGPTL4 associated with plasma lipids, TAG or NEFA concentration. The relative abundance of bifidobacteria following the inulin diet was higher, compared with the control diet. However, the changes in microbiota were not associated with plasma ANGPTL4 and the overall composition of the microbiota did not change between the dietary periods. Although weight was maintained throughout the dietary periods, weight was negatively associated with plasma ANGPTL4 concentration. In the adipose tissue, ANGPTL4 expression was correlated with leptin expression, but not with hypoxia-inducible factor 1α (HIF-1α) expression.

We examined carbon monoxide (CO) delivery by carbon monoxide-releasing molecule 2 (CORM-2) or hemoglobin (Hb) on cellular oxygen sensing and mitochondrial respiration in bovine aortic endothelial cells (BAECs). CORM-2 reduced hypoxia-inducible factor-1α (HIF-1α) and endothelin-1 (ET-1) expression in normoxic and hypoxic cells, but while Hb alone significantly reduced HIF-1α stabilization in hypoxic cells, CO delivered by Hb (Hb-CO) had no effect on HIF-1α stabilization. CO dose-dependently increased basal oxygen consumption and reduced overall mitochondrial respiratory capacity. Hb-CO increased basal oxygen consumption but did not alter respiratory capacity. Together, CO reduced ET-1, and, at low doses, had no effect on endothelial mitochondria oxygen consumption. CO ligation to Hb may be developed further as non-vasoactive oxygen therapeutic without compromising mitochondrial function.