ABSTRACT
Spinal cord injury (SCI) routinely causes the immediate loss and disruption of neurons followed by complicated secondary injuries, including inflammation, oxidative stress, and dense glial scar formation. Inhibitory factors in the lesion scar and poor intrinsic neural regeneration capacity restrict functional recovery after injury. Minocycline, which has neuroprotective activity, can alleviate secondary injury, but the long-term administration of this drug may cause toxicity. Polysialic acid (PSA) is a large cell-surface carbohydrate that is critical for central nervous system development and is capable of promoting precursor cell migration, axon path finding, and synaptic remodeling; thus, PSA plays a vital role in tissue repair and regeneration. Here, we developed a PSA-based minocycline-loaded nanodrug delivery system (PSM) for the synergistic therapy of spinal cord injury. The prepared PSM exerted marked anti-inflammatory and neuroprotective activities both in vitro and in vivo. The administration of PSM could significantly protect neurons and myelin sheaths from damage, reduce the formation of glial scar, recruit endogenous neural stem cells to the lesion site, and promote the regeneration of neurons and the extension of long axons throughout the glial scar, thereby largely improving the locomotor function of SCI rats and exerting a superior therapeutic effect. The findings might provide a novel strategy for SCI synergistic therapy and the utilization of PSA in other central nervous system diseases.
Subject(s)
Anti-Bacterial Agents/therapeutic use , Drug Carriers/therapeutic use , Minocycline/therapeutic use , Nerve Regeneration/drug effects , Neuroprotective Agents/therapeutic use , Sialic Acids/therapeutic use , Spinal Cord Injuries/drug therapy , Animals , Anti-Inflammatory Agents/therapeutic use , Micelles , Neurons/cytology , Neurons/drug effects , Neurons/pathology , Rats , Spinal Cord Injuries/pathology , Spinal Cord Injuries/physiopathologyABSTRACT
Both targeted and stimuli-sensitive drug-delivery systems (DDSs) have been developed to augment antitumor effects. However, lack of knowledge regarding tumor tissue targeting and different effects of the stimuli-sensitive DDSs in orthotropic and ectopic tumors have impeded further advances in their clinical applications. Herein, we first reported a pH-triggered micelle with sialic acid (SA)-driven targeting ability (SA-poly(ethylene glycol)-hydrazone linker-doxorubicin (DOX), SPD). The SPD micelles encapsulated with DOX (SPDD) showed sustained drug release over 48 h in response to the pH gradient in vivo, slow under physical conditions and accelerated in the acid tumor microenvironment. In addition, the SPD micelles showed 2.3-fold higher accumulation in tumors after 48 h compared to the micelles lacking the SA moiety. The overexpression of E-selectin on the inflammatory vascular endothelial cells surrounding the tumors increased the accumulation of SPD micelles in tumor tissues, whereas that on the tumor cells increased the internalization of micelles. Consequently, SPDD micelles exerted remarkable antitumor effects in both orthotopic and ectopic models. Application of SPDD micelles in the in situ model reduced the tumor volume (77.57 mm3 vs 62.13 mm3) and metastasis after treatment for 25 days. These results suggest that SA-driven targeted DDS with a pH-responsive switch has the potential to treat hepatocarcinoma effectively both ectopically and orthotopically.
Subject(s)
Antineoplastic Agents/administration & dosage , Carcinoma, Hepatocellular/drug therapy , Drug Delivery Systems/methods , Liver Neoplasms/drug therapy , Micelles , N-Acetylneuraminic Acid/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/toxicity , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Survival/drug effects , Doxorubicin/administration & dosage , Doxorubicin/chemistry , Doxorubicin/toxicity , Drug Carriers/chemistry , Female , Humans , Hydrogen-Ion Concentration , Liver Neoplasms/pathology , Mice , Mice, Inbred BALB CABSTRACT
The objective of this study was to examine the prevalence of hypertension and identify its contributory factors in the labor force population in Karamay. A total of 2819 adults (55.9% male adults) were interviewed and examined. The overall crude prevalence of hypertension was 32.4%. Among 914 hypertensive patients, 34.8% were aware of their diagnosis, 22.1% received treatment, and 5.6% achieved blood pressure control. Hypertension was significantly correlated with age, overweight/obesity, central obesity, diabetes, and dyslipidemia in both men and women. In addition, less education, alcohol consumption, and less walking were risk factors for men. Effective hypertension prevention and control programs are urgently needed to decrease the burden of hypertension in this region.
