Artesunate carriers induced ferroptosis to overcome biological barriers for anti-cancer

Artesunate (ART) has potent anticancer activity but it suffers from poor stability and low bioavailability in vivo due to the special endoperoxide moiety in the molecules. In this work, we fabricated programmable enzyme/reactive oxygen species (ROS) responsive ART complex carriers with size and charge adaptive regulation in order to improve stability and overcome biochemical hurdles of solid tumor. The complex carries (ART/AA-PAMAM@HA) were created by electrostatic interaction between dendrimer-ART/arachidonic acid (AA) (ART/AA-PAMAM) and hyaluronic acid (HA), which can proactively penetrate deeply into tumors and selective drug release. Specifically, ART induced Fenton reaction and produced a mass of ROS and lipid peroxides (LPO), leading to the depressing of GSH level and glutathione peroxidase 4 (GPX4) activity. Meanwhile, exogenous AA further promoted the accumulation of LPO by cascade regulating ferroptosis pathway. In the anti-tumor efficacy in vivo, the tumor inhibition ratio was achieved to 46.92%. This work shows a new anti-tumor strategy triggering ferroptosis via regulating redox homeostasis.

Combined chemo and photo therapy of programmable prodrug carriers to overcome delivery barriers against nasopharyngeal carcinoma

Indocyanine green (ICG) has been employed in medical diagnostics due to its superior photophysical characteristics. However, these advantages are offset by its quick body clearance and inferior photo-stability. In this work, programmable prodrug carriers for chemotherapy/PDT/PTT against nasopharyngeal carcinoma (NPC) were created in order to increase photo-stability and get around biochemical hurdles. The programmable prodrug carriers (PEG-PLA@DIT-PAMAM) that proactively penetrated deeply into NPC tumors and produced the deep phototherapy and selective drug release under laser irradiation was created by dendrimer-DOX/ICG/TPP (DIT-PAMAM) and PEGylated poly (α-lipoic acid) (PLA) copolymer. Long circulation times and minimal toxicity to mammalian cells are two benefits of PEG-coated carriers. The overexpressed GSH on the tumor cell or vascular endothelial cell of the NPC disintegrated the PEG-g-PLA chains and released the DIT-PAMAM nanoparticles after the carriers had reached the NPC tumor periphery. Small, positively charged DIT-PAMAM nanoparticles may penetrate tumors effectively and remain inside tumor for an extended period of time. In addition, the induced ROS cleaved the thioketal linkers for both DOX and nanoparticles and product hyperthermia (PTT) to kill cancer cells under laser irradiation, facilitating faster diffusion of nanoparticles and more effective tumor penetration with a programmable publication of DOX. The programmable prodrug carries showed high photo-stability high photo-stability, which enabled very effective PDT, PTT, and tumor-specific DOX release. With the goal of combining the effects of chemotherapy, PDT, and PTT against NPC, this research showed the great efficacy of programmable prodrug carriers.

Chitosan derivatives functionalized dual ROS-responsive nanocarriers to enhance synergistic oxidation-chemotherapy

The efficient triggering of prodrug release has become a challengeable task for stimuli-responsive nanomedicine utilized in cancer therapy due to the subtle differences between normal and tumor tissues and heterogeneity. In this work, a dual ROS-responsive nanocarriers with the ability to self-regulate the ROS level was constructed, which could gradually respond to the endogenous ROS to achieve effective, hierarchical and specific drug release in cancer cells. In brief, DOX was conjugated with MSNs via thioketal bonds and loaded with β-Lapachone. TPP modified chitosan was then coated to fabricate nanocarriers for mitochondria-specific delivery. The resultant nanocarriers respond to the endogenous ROS and release Lap specifically in cancer cells. Subsequently, the released Lap self-regulated the ROS level, resulting in the specific DOX release and mitochondrial damage in situ, enhancing synergistic oxidation-chemotherapy. The tumor inhibition Ratio was achieved to 78.49%. The multi-functional platform provides a novel remote drug delivery system in vivo.

[Application of acellular bovine pericardium patch in implant based immediate breast reconstruction]

Objective: To examine the clinical effect of acellular bovine pericardium patch in implant based immediate breast reconstruction. Methods: The clinicopathological information of 141 breast cancer patients, who admitted to Department of Breast Reconstruction and Oncoplastic Surgery, Tianjin Medical University Cancer Hospital, underwent immediate mammoplasty with implants combined with acellular bovine pericardium patches were analyzed from June 2016 to October 2019. All patients were female, with the age of (38.8±8.5) years (range: 13 to 60 years). The body mass index was (21.9±2.5) kg/m² (range: 16.0 to 32.3 kg/m²). There were 39 cases of duct carcinoma in situ, 46 cases of stage Ⅰ, 40 cases of stage Ⅱ and 16 cases of stage Ⅲ. All patients received nipple-areola-sparing mastectomy or skin-sparing mastectomy with sentinel lymph node biopsy or axillary lymph node dissection, and prosthesis implantation with sub-pectoralis combined with breast patch. The correlation of clinicopathological characters and complications was assessed by t test, χ² test, Fisher's exact probability method and Logistic regression. Pre-and post-operative aesthetic, quality of life scores were recorded. Results: The operation time (M(IQR)) was 3.6(1.5) hours (range: 3.0 to 6.5 hours). The early postoperative complication rate was 22.0% (31/141), prosthesis removal was the main postoperative complication, accounting for 64.5% (20/31) of the total complications, of which 15 cases occurred in the first 30 patients. The follow-up time was 28(8) months (range: 20 to 53 months), The most frequent long-term complications were capsular contracture and implant displacement, with the incidence of 11.2% (14/125) and 10.4% (13/125), respectively. Multivariate analysis showed that prosthesis volume ≥300 ml (OR=8.173, 95%CI: 1.302 to 51.315, P=0.021) and peri-areolar incision (OR=7.809, 95%CI: 2.162 to 28.211, P<0.01) were independent relative factors for the occurrence of short-term postoperative local complications. After 2 years of operation, the score of breast appearance satisfaction was 71.7±15.5, postoperative effect satisfaction was 90.4±9.5, psychological satisfaction was 90.7±17.1, sexual satisfaction was 70.1±25.1. The immediate postoperative satisfaction rate at discharge was 95.4% (134/141), and 17.6% (22/125) of patients had the intention to received revision surgery. Conclusions: Prosthesis volume ≥300 ml and peri-areolar incision were independent realtive factors for short-term local complications after bovine pericardium patch combined with prosthesis implantation in the immediate breast reconstruction. After completing the learning curve, the postoperative complications of the procedure could be decreased.

Brefeldin A delivery nanomicelles in hepatocellular carcinoma therapy: Characterization, cytotoxic evaluation in vitro, and antitumor efficiency in vivo

Hepatocellular carcinoma (HCC) is one of the major cancers with high mortality rate. Traditional drugs used in clinic are usually limited by the drug resistance and side effect and novel agents are still needed. Macrolide brefeldin A (BFA) is a well-known lead compound in cancer chemotherapy, however, with poor solubility and instability. In this study, to overcome these disadvantages, BFA was encapsulated in mixed nanomicelles based on TPGS and F127 copolymers (M-BFA). M-BFA was conferred high solubility, colloidal stability, and capability of sustained release of intact BFA. In vitro, M-BFA markedly inhibited the proliferation, induced G0/G1 phase arrest, and caspase-dependent apoptosis in human liver carcinoma HepG2 cells. Moreover, M-BFA also induced autophagic cell death via Akt/mTOR and ERK pathways. In HepG2 tumor-bearing xenograft mice, indocyanine green (ICG) as a fluorescent probe loaded in M-BFA distributed to the tumor tissue rapidly, prolonged the blood circulation, and improved the tumor accumulation capacity. More importantly, M-BFA (10 mg/kg) dramatically delayed the tumor progression and induced extensive necrosis of the tumor tissues. Taken together, the present work suggests that M-BFA has promising potential in HCC therapy.

[Effects of "qing kai ling" injection on experimental cerebral hematoma in rabbits]

OBJECTIVE

To observe the effect of "Qingkailing" (QKL) on cerebral hematoma.

METHODS

The experimental cerebral hematoma models were produced by injecting autogenous clot in the rabbit. The influences of QKL on blood gas, brain index, contents of water, sodium, potassium, calcium, magnesium in brain tissues and changes of cerebrovascular permeability, histomorphology at the third day, seventh day, fourteenth day after cerebral hematoma were observed.

RESULTS

In the pathological group brain index and contents of water, sodium, calcium of brain tissue, ventilation of lung were increased progressively, cerebrovascular permeability were raised obviously, especially in the side of hematoma (right brain). After the forming of cerebral hematoma cerebral edema was reduced, brain index, contents of water, sodium, calcium in brain tissue and cerebrovascular permeability, hyperventilation were all less than pathological group and close to the control group.

CONCLUSION

QKL was advantageous in the treatment of encephal edema induced by experimental cerebral hematoma.

Role of excitatory amino acids in regulation of rat pial microvasculature

Recently, attention has been drawn to the possibility that excitatory amino acids (EAAs) may play an important role in the pathogenesis of hypoxic-ischemic neuronal injury. Exaggerated release of EAAs and excessive stimulation of N-methyl-D-aspartate (NMDA) receptors and other EAA receptors have been suggested to contribute to neuronal death in ischemia and anoxia. A number of in vitro and in vivo experimental studies have shown that EAA-receptor antagonists exert a protective effect on the brain after cerebral ischemia. Because neurons are in close apposition to small intracerebral vessels, synaptically released EAAs might also regulate small blood vessel function. With the use of quantitative television microscopic observations, in vivo studies were undertaken on pial arterioles of rats. Perivascular administration of cumulative doses (10(-7)-10(-2) M) of L-glycine, L-glutamate, L-aspartate, and NMDA on the pial microvessels resulted in concentration-dependent constriction of pial arterioles (5-30% decreases in diameter) and cerebrovasospasm; the relative order of potency was aspartate > NMDA > glycine > glutamate. High concentrations of EAAs often resulted in rupture of postcapillary venules. No amine or opiate antagonist or cyclooxygenase inhibitor prevented or attenuated the effects of these putative EAAs. EAA-induced constriction and spasm of pial arterioles as well as rupture of venules could, however, be blocked by the noncompetitive NMDA-receptor antagonist MK-801 and by Mg2+. MK-801 also produced a concentration-dependent relaxation on normal pial arterioles. These results are compatible with the idea that a specific NMDA-receptor complex (RC) exists in rat cortical microvessels, which subserves vasoconstriction.(ABSTRACT TRUNCATED AT 250 WORDS)

[Age changes in location of mandibular foramen]

In order to understand the changes in location of the mandibular foramen with age in children, lateral cephalometric radiographs from 112 child and adult patients, including both males and females, were randomly selected according to age. The subjects were divided into 6 age-groups; 3, 5, 7, 9, 11 and adult. Certain lines and points were traced on the radiographs used. The location of the mandibular foramen was identified by two persons. The perpendicular distance from the center of the mandibular foramen to the occlusal plane and the location of the mandibular foramen relative to the ramus height (Ar-Kk), as well as to the ramus width (a-p), were measured. The mandibular foramen was located 4.12 mm below the occlusal plane at the age of 3. It subsequently moved upward with age. By the age of 9, it had reached approximately the same level as the occlusal plane. The foramen continued to move upward to 4.16 mm above the occlusal plane in the adult group. The height percentage averages ranged from the lower 1/3 of the ramus height in the 3 year-old group to the middle of the ramus height in adults. The depth percentage averages ranged from 67.8% in 3 year-old children to 61.7% in adults. For greater accuracy in anesthetic procedures, dentists should relate the locational changes in the mandibular foramen with age when performing block anesthesia for the inferior alveolar nerve.

Magnesium ions prevent phencyclidine-induced cerebrovasospasms and rupture of cerebral microvessels: direct in-vivo microcirculatory studies on the rat brain

Phencyclidine (PCP) abuse is reaching alarming proportions. PCP has recently been shown to induce hypertensive encephalopathies, microvascular cerebrovasospasm and acute intracerebral hemorrhage. Since we have shown in vitro that cerebral vasospasms induced by PCP could be completely reversed, or prevented, by use of organic calcium antagonists, we utilized a television microscope recording system to determine whether magnesium ions (Mg2+) could inhibit the ability of PCP to induce contraction of pial arterioles and its sequelae of microvascular damage. Administration of either MgCl2 or Mg aspartate HCl, i.a. or i.v. (1, 10, and 20 mumol/min), before or after administration of PCP produced dose-dependent inhibition (30-80%) of PCP-induced arteriolar spasms and the subsequent vascular damage. A variety of pharmacologic receptor antagonists and cyclooxygenase inhibitors failed to influence PCP-induced cerebrovasospasms. These data suggest that a naturally-occurring Ca2+ antagonist, viz. Mg2+, may be useful in the treatment of PCP intoxication and its cerebral vascular consequences.

Cocaine-induced cerebral vascular damage can be ameliorated by Mg2+ in rat brain

Cocaine HCl (10 micrograms/ml) delivered perivascularly to the surface of the rat brain resulted in rapid contraction of pial arterioles, which reduced the diameters by 26% compared to controls. This was followed by venular vasospasm and rupture of postcapillary venules and micro-hemorrhages at postcapillary sites. Administration of Mg aspartate HCl, by intraarterial or intravenous infusion (1, 10 and 20 mumol/min), before or after the cocaine, produced dose-dependent inhibition (20-85%) of the cocaine-induced arteriolar spasms and prevention and attenuation of the venular vasculotoxicity and hemorrhaging. These data suggest that magnesium salts might be useful agents in the treatment of cocaine-induced intoxication and prevention of brain damage.