l-Theanine improves functional recovery after traumatic spinal cord injury in rats.

BACKGROUND/PURPOSE: Spinal cord injury (SCI) is a devastating medical condition for which no effective pharmacological interventions exist. l-Theanine (LT), a major amino acid component of green tea, exhibits potent antioxidative and anti-inflammatory activities and protects against various neural injuries. Here, we evaluated the potential therapeutic effects of LT on the recovery of behavioral motor functions after SCI in rats and the underlying neuroprotective mechanisms. METHODS: SCI was induced by applying vascular clips to the dura through a four-level T5-T8 laminectomy, and saline or LT (10/30 mg/kg) was intrathecally administered at 1-, 6-, and 24-h post-SCI. At 72-h post-SCI, half of the rats from each group for each parameter were sacrificed, and their spinal cord was excised for measurement of malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase, catalase, tumor necrosis factor-α, interleukin-1ß/-6, myeloperoxidase, and caspase-3. The remaining rats from each group were subjected to Bresnahan locomotor-rating scale (BBB), inclined-plane, toe-spread, and hindfoot bar-grab tests at 1-, 4-, 7-, 10-, and 14-days post-SCI. RESULTS: LT treatment reduced NO and MDA levels, increased antioxidative strength, and markedly suppressed the levels of neuroinflammatory and apoptotic markers in the spinal cord after SCI. Moreover, LT treatment drastically promoted the recovery of behavioral motor functions post-SCI. CONCLUSION: Our findings revealed that LT can enhance the recovery of behavioral motor functions after SCI in rats, which related to the suppression of post-traumatic oxidative response, neural inflammation, and apoptosis. This evidence indicates that LT holds considerable potential for use in the clinical treatment/prevention of SCI-induced motor dysfunction.

Carbon-Doped TiO2 Activated by X-Ray Irradiation for the Generation of Reactive Oxygen Species to Enhance Photodynamic Therapy in Tumor Treatment.

Traditional photodynamic therapy (PDT) is limited by the penetration depth of visible light. Although the light source has been changed to near infrared, infrared light is unable to overcome the penetration barrier and it is only effective at the surface of the tumors. In this study, we used X-ray as a light source for deep-seated tumor treatment. A particle with a narrow band gap when exposed to soft X-rays would produce reactive oxygen species (ROS) to kill tumor cell, with less damage to the normal tissues. Anatase TiO2 has been studied as a photosensitizer in PDT. In the experiment, C was doped into the anatase lattice at an optimum atomic ratio to make the band gap narrower, which would be activated by X-ray to produce more ROS and kill tumor cells under stress. The results showed that the synthesized TiO2:C particles were identified as crystal structures of anatase. The synthesized particles could be activated effectively by soft X-rays to produce ROS, to degrade methylene blue by up to 30.4%. Once TiO2:C was activated by X-ray irradiation, the death rate of A549 cells in in vitro testing was as high as 16.57%, on day 2. In the animal study, the tumor size gradually decreased after treatment with TiO2:C and exposure to X-rays on day 0 and day 8. On day 14, the tumor declined to nearly half of its initial volume, while the tumor in the control group was twice its initial volume. After the animal was sacrificed, blood, and major organs were harvested for further analysis and examination, with data fully supporting the safety of the treatment. Based on the results of the study, we believe that TiO2:C when exposed to X-rays could overcome the limitation of penetration depth and could improve PDT effects by inhibiting tumor growth effectively and safely, in vivo.

ROS-induced HepG2 cell death from hyperthermia using magnetic hydroxyapatite nanoparticles.

HepG2 cell death with magnetic hyperthermia (MHT) using hydroxyapatite nanoparticles (mHAPs) and alternating magnetic fields (AMF) was investigated in vitro. The mHAPs were synthesized as thermo-seeds by co-precipitation with the addition of Fe2+. The grain size of the HAPs and iron oxide magnetic were 39.1 and 19.5 nm and were calculated by the Scherrer formula. The HepG2 cells were cultured with mHAPs and exposed to an AMF for 30 min yielding maximum temperatures of 43 ± 0.5 °C. After heating, the cell viability was reduced by 50% relative to controls, lactate dehydrogenase (LDH) concentrations measured in media were three-fold greater than those measured in all control groups. Readouts of toxicity by live/dead staining were consistent with cell viability and LDH assay results. Measured reactive oxygen species (ROS) in cells exposed to MHT were two-fold greater than in control groups. Results of cDNA microarray and Western blotting revealed tantalizing evidence of ATM and GADD45 downregulation with possible MKK3/MKK6 and ATF-2 of p38 MAPK inhibition upon exposure to mHAPs and AMF combinations. These results suggest that the combination of mHAPs and AMF can increase intracellular concentrations of ROS to cause DNA damage, which leads to cell death that complement heat stress related biological effects.

First-in-human pilot trial of combined intracoronary and intravenous mesenchymal stem cell therapy in acute myocardial infarction.

Background: Acute ST-elevation myocardial infarction (STEMI) elicits a robust cardiomyocyte death and inflammatory responses despite timely revascularization. Objectives: This phase 1, open-label, single-arm, first-in-human study aimed to assess the safety and efficacy of combined intracoronary (IC) and intravenous (IV) transplantation of umbilical cord-derived mesenchymal stem cells (UMSC01) for heart repair in STEMI patients with impaired left ventricular ejection fraction (LVEF 30-49%) following successful reperfusion by percutaneous coronary intervention. Methods: Consenting patients received the first dose of UMSC01 through IC injection 4-5 days after STEMI followed by the second dose of UMSC01 via IV infusion 2 days later. The primary endpoint was occurrence of any treatment-related adverse events and the secondary endpoint was changes of serum biomarkers and heart function by cardiac magnetic resonance imaging during a 12-month follow-up period. Results: Eight patients gave informed consents, of whom six completed the study. None of the subjects experienced treatment-related serious adverse events or major adverse cardiovascular events during IC or IV infusion of UMSC01 and during the follow-up period. The NT-proBNP level decreased (1362 ± 1801 vs. 109 ± 115 pg/mL, p = 0.0313), the LVEF increased (52.67 ± 12.75% vs. 62.47 ± 17.35%, p = 0.0246), and the wall motion score decreased (26.33 ± 5.57 vs. 22.33 ± 5.85, p = 0.0180) at the 12-month follow-up compared to the baseline values. The serial changes of LVEF were 0.67 ± 3.98, 8.09 ± 6.18, 9.04 ± 10.91, and 9.80 ± 7.56 at 1, 3, 6, and 12 months, respectively as compared to the baseline. Conclusion: This pilot study shows that combined IC and IV transplantation of UMSC01 in STEMI patients with impaired LVEF appears to be safe, feasible, and potentially beneficial in improving heart function. Further phase 2 studies are required to explore the effectiveness of dual-route transplantation of UMSC01 in STEMI patients.

Fish-Scale Collagen Membrane Seeded with Corneal Endothelial Cells as Alternative Graft for Endothelial Keratoplasty Transplantation.

The human corneal endothelium has limited regeneration capacity. Several methods have been developed in an attempt to repair it. Descemet stripping automated endothelial keratoplasty (DSAEK) is commonly performed on patients with endothelial dysfunction. However, donor demand far exceeds donor supply. Here, we prepared fish-scale collagen membrane (FSCM) and seeded it with CECs in preparation for corneal endothelial transplantation. The fish scales were decellularized, decalcified, and curved. The FSCM was inspected by fluorescence microscopy, SEM, and TGA to validate decellularization, microstructure, and decalcification, respectively. The cytotoxicity of FSCM and the viability of the cells in contact with it were evaluated by LDH and WST-1, respectively. CEC tight junctions and ZO-1 structure were observed by SEM and confocal microscopy. FSCM seeded with CECs were implanted to rabbit anterior chambers to evaluate host tissue reactions to it. FSCM biocompatibility and durability were also assessed. The results showed that FSCM has excellent transparency, adequate water content, and good biocompatibility. The cultivated CECs mounted on the FSCM were similar to normal CECs in vivo. The FSCM plus CECs developed here have high potential efficacy for endothelial keratoplasty transplantation.

Fluorinated Montmorillonite and 3YSZ as the Inorganic Fillers in Fluoride-Releasing and Rechargeable Dental Composition Resin.

Dental caries (tooth decay) is the most frequent oral disease in humans. Filling cavities with a dental restorative material is the most common treatment, and glass ionomer cements are the main fluoride ion release restorative materials. The goal of this study was to develop a restorative compound with superior fluoride ion release and recharge abilities. Previously developed fluorinated bentolite and hydrophobized 3YSZ were used as two different inorganic fillers mixed in a bisphenol A-glycidyl methacrylate (Bis-GMA) matrix. XRD, FTIR, and TGA were used to determine the hydrophobic modification of these two inorganic fillers. In mechanical tests, including diameter tensile strength, flexural strength, and wear resistance, the developed composite resin was significantly superior to the commercial control. A WST-1 assay was used to confirm that the material displayed good biocompatibility. Furthermore, the simulation of the oral environment confirmed that the composite resin had good fluoride ion release and reloading abilities. Thus, the composite resin developed in this study may reduce secondary caries and provide a new choice for future clinical treatments.

Effects of Highly Oxygenated Water in a Hyperuricemia Rat Model.

Recent years have seen a rapidly rising number of oxygenated water brands that claim to impart health benefits and increase athletic performance by improving oxygen availability in the body. Drinks with higher dissolved oxygen concentrations have in recent times gained popularity as potential ergogenic aids, despite the lack of evidence regarding their efficacy. The aim of this study was to characterize oxygenated water and assess the improvement in uric acid metabolism while identifying performance enhancements in animals administered oxygenated water. Oxygenated water was characterized by hydrogen and oxygen nuclear magnetic resonance (NMR) spectroscopy. Hyperuricemia in rats was induced by treatment with oxonic acid potassium salt, and the animals were given oxygenated drinking water before, during, or after oxonic acid treatment. Serum uric acid was measured to confirm the effects on uric acid metabolism. Following oxygenation, the full width at half maximum (FWHM) was reduced to 11.56 Hz and 64.16 Hz in the hydrogen and oxygen NMR spectra, respectively. Oxygenated water molecule clusters were reduced in size due to the reduction in FWHM. Oxygen concentration did not vary significantly with increased temperature. However, standing time played a critical role in the amount of oxygen dissolved in the water. The rat studies indicated that oxygenated water reduced serum uric acid levels and their rate of increase and enhanced uric acid metabolism. A significant improvement in uric acid metabolism and rate of increase in serum uric acid concentration was observed in hyperuricemic rats administered oxygenated water compared to that in rats administered regular water. High oxygen concentrations enhanced the rate of oxygen absorption, leading to increased glycolysis and mitochondrial protein synthesis. Therefore, oxygenated water is a potential adjuvant therapy or health food for treatment of hyperuricemia.

Protective Effect of (-)Epigallocatechin-3-gallate on Rotenone-Induced Parkinsonism-like Symptoms in Rats.

Rotenone (ROT)-induced neurotoxicity has been used for decades as an animal model of Parkinson's disease (PD) in humans. This model exhibits pathophysiological features similar to those reported in patients with PD, namely, striatal nitrosative and oxidative stress, mitochondrial dysfunction, and neural cytoarchitecture alteration. (-)Epigallocatechin-3-gallate (EGCG), the most abundant and potent green tea catechin, has notable anti-oxidative, anti-inflammatory, and neuroprotective effects. The objective of the present study was to investigate the potential protective effects of EGCG on ROT-induced motor and neurochemical dysfunctions in rats. Furthermore, we also aimed to study the neuroprotective mechanisms underlying these effects. ROT treatment (0.5 mg/kg s.c., 21 days) reduced body weight and induced significant motor impairments as assessed using an open-field test, rotarod test, grip strength measurement, and beam-crossing task. EGCG treatment (100 or 300 mg/kg i.p., 60 min prior to ROT administration, 21 days) prevented most of the ROT-induced motor impairments. Moreover, EGCG treatment reduced ROT-induced nitric oxide (NO) level and lipid peroxidation (LPO) production; increased the activity of succinate dehydrogenase (SDH), ATPase, and ETC enzymes and the levels of catecholamines in the striatum; and reduced the levels of neuroinflammatory and apoptotic markers. These results demonstrate the possible neuroprotective effects of EGCG against ROT-induced motor impairments, including anti-oxidatory effect, prevention of mitochondrial dysfunction, prevention of neurochemical deficiency, anti-neuroinflammatory effect, and anti-apoptotic effect. This is the first report about the neuroprotective effect of EGCG against ROT-induced motor impairments, and the above evidence provides a potential clinically relevant role for EGCG in delaying or treating human PD.

Fluorinated Montmorillonite Composite Resin as a Dental Pit and Fissure Sealant.

Molar pits and fissures tend to be affected by caries due to cleaning difficulties. As such, the filling of pits and cracks with sealants is common to deter the onset of caries. However, current clinical practices rely on sealants that lack the ability to release and recharge fluoride ions. Thus, we herein report the development of a fluoride-montmorillonite nanocomposite resin that has the potential to provide sustained release of fluoride due to the strong adsorption of fluoride by montmorillonite. X-ray diffractometry, thermogravimetric analysis, and Fourier-transform infrared spectroscopy were employed to confirm the successful insertion of the polymer into the interlayer structure. The mechanical properties (viscosity, hardening depth, hardness, diametral tensile strength, flexural strength, and wear resistance) of the developed composite resin were then examined, and simulation of the oral environment demonstrated a good fluoride ion release and recharge ability for the effective prevention of dental caries. Finally, we demonstrated the non-cytotoxic nature of this material using the water-soluble tetrazolium salt (WST-1) test. We expect that the described fluoride-containing composite resin may become a new clinical option in the near future.

Hafnium-doped hydroxyapatite nanoparticles with ionizing radiation for lung cancer treatment.

UNLABELLED: Recently, photodynamic therapy (PDT) is one of the new clinical options by generating cytotoxic reactive oxygen species (ROS) to kill cancer cells. However, the optical approach of PDT is limited by tissue penetration depth of visible light. In this study, we propose that a ROS-enhanced nanoparticle, hafnium-doped hydroxyapatite (Hf:HAp), which is a material to yield large quantities of ROS inside the cells when the nanoparticles are bombarded with high penetrating power of ionizing radiation. Hf:HAp nanoparticles are generated by wet chemical precipitation with total doping concentration of 15mol% Hf(4+) relative to Ca(2+) in HAp host material. The results show that the HAp particles could be successfully doped with Hf ions, resulted in the formation of nano-sized rod-like shape and with pH-dependent solubility. The impact of ionizing radiation on Hf:HAp nanoparticles is assessed by using in-vitro and in-vivo model using A549 cell line. The 2',7'-dichlorofluorescein diacetate (DCFH-DA) results reveal that after being exposed to gamma rays, Hf:HAp could significantly lead to the formation of ROS in cells. Both cell viability (WST-1) and cytotoxicity (LDH) assay show the consistent results that A549 lung cancer cell lines are damaged with changes in the cells' ROS level. The in-vivo studies further demonstrate that the tumor growth is inhibited owing to the cells apoptosis when Hf:HAp nanoparticles are bombarded with ionizing radiation. This finding offer a new therapeutic method of interacting with ionizing radiation and demonstrate the potential of Hf:HAp nanoparticles in tumor treatment, such as being used in a palliative treatment after lung surgical procedure. STATEMENT OF SIGNIFICANCE: Photodynamic therapy (PDT) is one of the new clinical options by generating cytotoxic reactive oxygen species (ROS) to kill cancer cells. Unfortunately, the approach of PDT is usually limited to the treatment of systemic disease and deeper tumor, due to the limited tissue penetration depth of visible light (620-690nm). Here we report a ROS-enhanced nanoparticle, hafnium-doped hydroxyapatite (Hf:HAp), which can trigger ROS when particles are irradiated with high penetrating power of ionizing radiation. The present study provides quantitative data relating ROS generation and the therapeutic effect of Hf:HAp nanoparticles in lung cancer cells. As such, this material has opened an innovative window for deeper tumor and systemic disease treatment.