Biocatalytic nitric oxide generating hydrogels with enhanced anti-inflammatory, cell migration, and angiogenic capabilities for wound healing applications.

Although wound healing is a normal physiological process in the human body, it is often impaired by bacterial infections, ischemia, hypoxia, and excess inflammation, which can lead to chronic and non-healing wounds. Recently, injectable hydrogels with controlled nitric oxide (NO) release behaviour have become potential wound healing therapeutic agents due to their excellent biochemical, mechanical, and biological properties. Here, we proposed novel multifunctional NO-releasing hydrogels that could regulate various wound healing processes, including hemostasis, inflammation, cell proliferation and angiogenesis. By incorporating the copper nanoparticles (NPs) in the network of dual enzymatically crosslinked gelatin hydrogels (GH/Cu), NO was in situ produced via the Cu-catalyzed decomposition of endogenous RSNOs available in the blood, thus resolving the intrinsic shortcomings of NO therapies, such as the short storage and release time, as well as the burst and uncontrollable release modes. We demonstrated that the NO-releasing gelatin hydrogels enhanced the proliferation and migration of endothelial cells, while promoting the M2 (anti-inflammatory) polarization of the macrophage. Furthermore, the effects of NO release on angiogenesis were evaluated using an in vitro tube formation assay and in ovo chicken chorioallantoic membrane (CAM) assay, which revealed that GH/Cu hydrogels could significantly facilitate neovascularization, consistent with the in vivo results. Therefore, we suggested that these hydrogel systems would significantly enhance the wound healing process through the synergistic effects of the hydrogels and NO, and hence could be used as advanced wound dressing materials.

Gelatin microgel-coated balloon catheter with enhanced delivery of everolimus for long-term vascular patency.

In-stent restenosis (ISR) after percutaneous coronary intervention is a major reason for limited long-term patency due to complex neointimal proliferation caused by vascular injury. Drug-coated balloon (DCB) has been developed to treat various cardiovascular diseases including ISR by providing anti-proliferative drugs into blood vessel tissues. However, a significant proportion of the drug is lost during balloon tracking, resulting in ineffective drug delivery to the target region. In this study, we report an everolimus-coated balloon (ECB) using everolimus-loaded gelatin-hydroxyphenyl propionic acid microgel (GM) with enhanced everolimus delivery to vascular walls for long-term patency. GM with high drug loading (> 97%) was simply prepared by homogenizing enzyme-mediated crosslinked hydrogels. The optimal condition to prepare GM-coated ECB (GM-ECB) was established by changing homogenization time and ethanol solvent concentration (30 ∼ 80%). In vitro sustained everolimus release for 30 d, and cellular efficacy using smooth muscle cells and vascular endothelial cells were evaluated. Additionally, an in vivo drug transfer levels of GM-ECB using rabbit femoral arteries were assessed with reduced drug loss and efficient drug delivery capability. Finally, using ISR-induced porcine models, effective in vivo vascular patency 4 weeks after treatment of ECBs was also confirmed. Thus, this study strongly demonstrates that GM can be used as a potential drug delivery platform for DCB application. STATEMENT OF SIGNIFICANCE: We report an ECB using everolimus-loaded GM prepared by homogenization of enzymatic cross-linked hydrogel. GM showed efficient drug loading (> 97 %) and controllable size. GM-ECB exhibited potential to deliver everolimus in a sustained manner to target area with drug efficacy and viability against SMC and EC. Although GM-ECB had much lower drug content compared to controls, animal study demonstrated enhanced drug transfer and reduced drug loss of GM-ECB due to the protection of encapsulated drugs by GM, and the possible interaction between GM and endothelium. Finally, vascular patency and safety were assessed using ISR-induced porcine models. We suggest an advanced DCB strategy to alleviate rapid drug clearance by bloodstream while improving drug delivery for a long-term vascular patency.

Deer Velvet and Eleutherococcus senticosus Mixture Regulated Immune Function in C57BL/6N Mice with Immunosuppression Induced by Forced Swimming.

Immunosuppression occurs in response to a variety of external antigens. However, various immune cells and cytokines can activate the immune system. In this study, it was found that fermented deer velvet (FD) and fermented Eleutherococcus senticosus (FE) extract (FDE) mixtures regulated the immunity of animals that underwent induced immunosuppression through forced swimming exercise (FSE). Seven mouse treatment groups were included in the experiment: normal controls, FSE controls, positive controls (FSE+red ginseng 300 mg/kg body weight), FD200 (FSE+FD 200 mg/kg body weight), FE200 (FSE+FE 200 mg/kg body weight), FDE50 (FSE+FDE 50 mg/kg body weight), and FDE200 (FSE+FDE 200 mg/kg body weight). Oral intake of experimental and control substances lasted for 2 weeks. Oral FDE intake increased cell counts for major histocompatibility complex (MHC) I, MHC II, CD4(+) T cells, and CD8(+) T cells compared with controls. Moreover, FDE increased Th1 (interleukin [IL]-2 and interferon gamma) cytokine proliferation, T cell proliferation, IL-12 and IL-15 production, and natural killer cell activity compared with controls. In addition, FDE inhibited Th2 cytokines (IL-4, IL-6, IL-10, and tumor necrosis factor alpha) and nitric oxide production, increased B cell proliferation and leukocyte count, and promoted immunoglobulin A and G serum levels compared with controls. Thus, the finding that FDE increased immune function in an immunosuppression model suggests that FDE has immunomodulatory capacity.

Echinacea purpurea Extract Enhances Natural Killer Cell Activity In Vivo by Upregulating MHC II and Th1-type CD4+ T Cell Responses.

There are a number of factors that cause immune system disruption, including infection caused by foreign antigens and decreased immunity due to excessive exercise, and public interest in improving immunity is growing. In this study, we investigate the immunomodulatory effects of Echinacea purpurea (E) extract in C57BL/6N mice that were exposed to a forced swimming exercise. There were six experimental groups as follows: wild-type, forced swimming exercise control, positive control (red ginseng, 300 mg/kg), and E (50, 100, and 200 mg/kg b.w.) groups. The mice were administered the E extract for 2 weeks. We detected chicoric acid, the active substance of E, through high-performance liquid chromatography and evaluated changes in the following laboratory values in response to forced swimming exercise using flow cytometry and ELISA: the major histocompatibility complex (MHC), CD4+ and CD8+ T cells, Th1 and Th2 cytokines, natural killer (NK) cell activity, and number of leukocytes. Oral E intake increased levels of MHC II, CD4+ T cells, Th1 cytokines, and NK cell activity. In addition, E treatment increased B cell proliferation, leukocyte counts, and immunoglobulin levels. Taken together, these results suggest that the chicoric acid of E can improve immune response by controlling NK cell activity, which may be a useful function for immunomodulation systems.

Effects of a Mixture of Humulus japonicus on Longitudinal Bone Growth in Hypophysectomized Rats.

Previously, we reported that the administration of a mixture of Humulus japonicus (MH) increased the longitudinal bone growth rate in Sprague Dawley rats. In this study, we investigated the effects of the dietary administration of MH on longitudinal bone growth in growth hormone (GH)-deficient hypophysectomized male and female rats to determine whether the effect of MH was similar to that of GH. We measured the nose-to-anus and nose-to-tail length gain, femur and tibia lengths, growth plate zones, and expression of insulin-like growth factor-1 (IGF-1) and IGF-binding protein-3 (IGFBP-3) after the dietary administration of MH or the injection of GH into hypophysectomized rats for 4 weeks. Results demonstrated that the dietary administration of MH had no effect on longitudinal bone growth, whereas the injection of GH increased the nose-to-tail length gain and femur and tibia lengths in hypophysectomized rats. In addition, MH did not affect the growth plate, bone mineralization, and expression of IGF-1 and IGFBP-3. These findings indicate that MH does not exert a GH-like effect and that the effects of MH and GH on longitudinal bone growth involve different pathways.

Emblica officinalis and Hordeum vulgare L. Mixture Regulates Lipolytic Activity in Differentiated 3T3-L1 Cells.

In this study, we investigated the lipolytic effects of an Emblica officinalis (Indian gooseberry [IG]) and Hordeum vulgare L. (barley sprout [BP]) mixture on differentiated 3T3-L1 cells. On the ninth day of differentiation, Oil red O staining and Western blotting were performed; additionally, glycerol release and triglyceride (TG), fatty acid (FA), and cyclic adenosine monophosphate (cAMP) levels were measured. Compared to the differentiation-induced control (C) group, the IG and BP mixture inhibited intracellular TG and FA levels by 61.7% and 48.9%, respectively, at a concentration of 200 µg/mL. Moreover, the mixture increased glycerol release and cAMP levels by more than twofold more than those in the C group. Western blotting was performed to confirm the protein expression involved in lipolysis, and the IG and BP mixture was found to significantly increase the protein activities of AMP-activated protein kinase, protein kinase A, and hormone-sensitive lipase compared to those of the C group. Furthermore, the mixture significantly inhibited the protein activities of phosphodiesterase 3B, adipose TG lipase, and perilipin compared to those of the C group at a concentration of 200 µg/mL. We found that the IG and BP mixture activates the cAMP pathway and regulates lipolytic enzymes, which are necessary for lipolysis. In conclusion, our findings suggest that the IG and BP mixture can be potentially developed as a new material for targeting mechanisms underlying lipolysis.

Antarctic Krill Oil Ameliorates Monosodium Iodoacetate-Induced Irregularities in Articular Cartilage and Inflammatory Response in the Rat Models of Osteoarthritis.

The aim of this study was to examine the effects of Antarctic krill oil (FJH-KO) in a rat model of monosodium iodoacetate (MIA) induced osteoarthritis. The effect of FJH-KO on the development and severity of MIA-induced osteoarthritis was assessed using hematoxylin and eosin (H&E) staining and micro-CT. The expression of PGE2, pro-inflammatory cytokines (IL-1ß, TNF-α), and arthritics related genes in osteoarthritic rats in response to FJH-KO supplementation was investigated using real time PCR. FJH-KO supplementation in the arthritic rat model reduced tissue damage, cartilage degeneration, and reduced the MIA-induced irregularities in articular cartilage surface. Serum PGE2, IL-1ß, IL-6, and TNF-α levels were higher in MIA treated animals, but these levels decreased upon FJH-KO supplementation. When FJH-KO was provided at a dose of 150 mg/kg b.w to MIA-treated animals, it significantly increased the mRNA expression of anabolic factors. The mRNA expression of catabolic factors was significantly decreased MIA-treated animals that were provided FJH-KO at a dose of 100 and 150 mg/kg b.w. Moreover, the mRNA expression of inflammatory mediators was significantly decreased MIA-treated animals supplemented with FJH-KO. These results suggest supplementation with FJH-KO ameliorates the irregularities in articular cartilage surface and improves the inflammatory response in the osteoarthritis. Thus, FJH-KO could serve as a potential therapeutic agent for osteoarthritis treatment.

A Mixture of Humulus japonicus Increases Longitudinal Bone Growth Rate in Sprague Dawley Rats.

The aim of this study was to investigate the effects of administration of a mixture of Humulus japonicus (MH) on longitudinal bone growth in normal Sprague Dawley (SD) rats. We measured the femur and tibia length, growth plate area, proliferation of chondrocytes, and expression of insulin-like growth factor-1 (IGF-I) and IGF binding protein-3 (IGFBP-3), and Janus kinase 2 (JAK2)/signal transducer and activator of transcription 5 (STAT5) phosphorylation after dietary administration of MH in SD rats for four weeks. The nose-tail length gain and length of femur and tibia increased significantly in the group that received MH for a period of four weeks. We performed H&E staining and Bromodeoxyuridine/5-Bromo-2'-Deoxyuridine (BrdU) staining to examine the effect of dietary administration of MH on the growth plate and the proliferation of chondrocytes and found that MH stimulated the proliferation of chondrocytes and contributed to increased growth plate height during the process of longitudinal bone growth. In addition, serum levels of IGF-1 and IGFBP-3 and expression of IGF-1 and IGFBP-3 mRNAs in the liver and bone were increased, and phosphorylation of JAK2/STAT5 in the liver was increased in the MH groups. Based on these results, we suggest that the effect of MH on longitudinal bone growth is mediated by increased JAK2/STAT5-induced IGF-1 production.

The effect of neuromuscular electrical stimulation with different electrode positions on swallowing in stroke patients with oropharyngeal dysphagia: A randomized trial.

OBJECTIVE: To examine the effects of neuromuscular electrical stimulation (NMES) on oropharyngeal swallowing function according to 2 types of placement, acting as assistance and as resistance, in stroke patients with dysphagia. METHODS: Thirty-eight stroke patients with dysphasia were randomly assigned to the suprahyoid group (SMG), or infrahyoid muscle group (IMG); 26 patients completed the intervention and were included in the analysis. In the SMG, the electrodes were placed on the region between the jaw and the hyoid bone, whereas in the IMG, the electrodes were placed on the region below the hyoid for the targeted infrahyoid muscles. Both groups received NMES for 30 min/d, 5 d/wk, for 4 weeks and conventional dysphagia therapy. Swallowing function was measured using the Videofluoroscopic Dysphagia Scale and Penetration-Aspiration Scale based on videofluoroscopic swallowing study. Oral dietary intake was measured using the Functional Oral Intake Scale. RESULTS: Both groups showed significant improvements in oropharyngeal function and level of functional oral intake, but there was no significant difference between the two groups. However, the SMG showed a more reduced penetration-aspiration, compared with the IMG. CONCLUSIONS: Altogether, these data demonstrate that 2 types of NMES placements have a similar effect on improving swallowing function and oral diet intake in patients with dysphagia.

Effect of effortful swallowing training on tongue strength and oropharyngeal swallowing function in stroke patients with dysphagia: a double-blind, randomized controlled trial.

BACKGROUND: Effortful swallowing training (EST) is a remedial method for the training of swallowing-related muscles in the oropharyngeal phase. However, clinical evidence of its effectiveness is insufficient. AIMS: To investigate the effects of EST on tongue strength and swallowing function in patients with stroke. METHODS & PROCEDURES: Stroke patients with dysphagia were randomly assigned to one of two groups: an experimental group (n = 12) and a control group (n = 12). The experimental group underwent EST, while the control group performed saliva swallowing. Training was conducted 5 days per week for 4 weeks. Both groups underwent conventional dysphagia treatment for 30 min/day, 5 days/week for 4 weeks. OUTCOMES & RESULTS: Tongue strength was assessed using the Iowa Oral Performance Instrument. The Videofluoroscopic Dysphagia Scale (VDS), based on a videofluoroscopic swallowing study, was used to analyze oropharyngeal swallowing function. The experimental group showed greater improvements in anterior and posterior tongue strength compared with the control group (p = 0.046 and 0.042, respectively), and greater improvement in the oral phases of the VDS (p = 0.017). CONCLUSIONS & IMPLICATIONS: We recommend EST as a remedial strategy for improving tongue strength and oral swallowing function in patients with stroke.

Comparison of orbicularis oris muscle strength and endurance in young and elderly adults.

[Purpose] The purpose of this study was to compare the strength and endurance of the orbicularis oris muscle in healthy Korean (young vs. elderly adults). [Participants and Methods] A total of 60 participants (30 young adults and 30 elderly adults) were recruited. The Iowa Oral Performance Instrument was used to measure orbicularis oris muscle maximal strength and endurance. [Results] Elderly adults showed significantly lower orbicularis oris muscle strength and endurance than younger adults. [Conclusion] This study confirmed a significant age-related decrease in orbicularis oris muscle strength and endurance. The data collected will be useful as a basis for future on speech and swallowing therapy.

Oropharyngeal swallowing function in patients with presbyphagia.

[Purpose] This study investigated the characteristics of oropharyngeal swallowing function in patients with presbyphagia. [Participants and Methods] Data for 25 patients with presbyphagia were retrospectively analyzed. The oropharyngeal swallowing function was evaluated using VDS based on videofluoroscopic swallowing study. [Results] Lip closure, mastication, laryngeal elevation, and aspiration showed a relative decrease in function. [Conclusion] This study showed a reduction in oropharyngeal swallowing in patients with presbyphagia. Our results may help in the diagnosis and treatment of presbyphagia.

Effects of neuromuscular electrical stimulation in patients with Parkinson's disease and dysphagia: A randomized, single-blind, placebo-controlled trial.

BACKGROUND: Neuromuscular electrical stimulation has been used to improve swallowing function in neurologic patients with dysphagia, but its effect on patients with dysphagia and Parkinson's disease remains unclear. OBJECTIVES: This study aimed to identify the effect of effortful swallowing combined with neuromuscular electrical stimulation as a novel treatment approach in dysphagic patients with Parkinson's disease. METHODS: Participants were randomly allocated to an experimental group (n = 9) or a placebo group (n = 9). The experimental group simultaneously received neuromuscular electrical stimulation with effortful swallowing, while the placebo group received sham neuromuscular electrical stimulation with effortful swallowing. All participants received the treatment for 30 min/day at five sessions per week for 4 weeks. Both groups also received the same conventional dysphagia therapy. RESULTS: The experimental group showed significant differences in horizontal movement (p = 0.038) and vertical movement (p = 0.042) compared to the placebo group, but showed no significant differences in the oral (p = 0.648) or pharyngeal phase (p = 0.329) of the Videofluoroscopic Dysphagia Scale compared to the placebo group, except for the Penetration-Aspiration Scale (p = 0.039). CONCLUSIONS: We demonstrated that neuromuscular electrical stimulation applied to the infrahyoid region combined with effortful swallowing effectively increased hyoid bone movement and reduced aspiration in dysphagic patients with Parkinson's disease.

Effect of chin tuck against resistance exercise on patients with dysphagia following stroke: A randomized pilot study.

BACKGROUND: Recently, chin tuck against resistance exercise (CTAR) has been reported as a remedial treatment for pharyngeal dysphagia. However, the clinical evidence of the effect is still lacking. OBJECTIVE: This study investigated the effect of CTAR on the swallowing function in patients with dysphagia following subacute stroke. METHODS: The patients were randomly assigned to an experimental (n = 11) or a control group (n = 11). The experimental group performed CTAR using the CTAR device. The control group received only conventional dysphagia treatment. Both groups received training on five days a week, for four weeks. The swallowing function was measured using functional dysphagia scale (FDS) and penetration-aspiration scale (PAS), based on a videofluoroscopic swallowing study (VFSS). RESULTS: The experimental group showed more improvements in the oral cavity, laryngeal elevation/epiglottic closure, residue in valleculae, and residue in pyriform sinuses of FDS and PAS compared to the control group (p < 0.05, all). CONCLUSIONS: This study demonstrated that CTAR is effective in improving the pharyngeal swallowing function in patients with dysphagia after stroke. Therefore, we recommend CTAR as a new remedial training alternative to HLE.

Sulfobetaine methacrylate hydrogel-coated anti-fouling surfaces for implantable biomedical devices.

BACKGROUND: Zwitterionic molecules have been widely studied as coating materials for preparing anti-fouling surfaces because they possess strong hydration properties that can resist non-specific protein adsorption. Numerous studies on surface modification using zwitterionic molecules have been investigated, such as electrochemically mediated and photoinitiated radical polymerization. However, these methods have some limitations, including multi-step process, difficulties in producing thick and dense layers as well as the requirement of extra facilities. In this study, we report a novel zwitterionic hydrogel-coating method via Fenton reaction for the preparation of anti-fouling surfaces. METHODS: Sulfobetaine methacrylate (SBMA) hydrogel was coated on polyurethane (PU) by polymerization of SBMA molecules via the Fenton reaction. The coated surfaces were characterized by the measurements of water contact angle, SEM and XPS. The anti-fouling properties of the modified surfaces were evaluated by reductions of fibrinogen absorption and cell (human dermal fibroblasts, hDFBs) adhesion. RESULTS: SBMA hydrogel layers were coated on the PU substrates and these layers have a high affinity for water. The hydrogel coatings were highly stable for 7 days, without a significant change in surface wettability. Importantly, the hydrogel-coated PU substrates decrease 80% of surface-adsorbed fibrinogen and surface-attached hDFBs (compared with uncoated PU substrates), indicating the excellent anti-fouling activities of modified surfaces. CONCLUSIONS: The hydrogel-coated PU surfaces prepared by Fenton reaction with anti-fouling properties could have potential uses for implantable biomedical devices.

Effects of resistance expiratory muscle strength training in elderly patients with dysphagic stroke.

BACKGROUND: Recently, resistance expiratory muscle strength training (EMST) has been reported as a remedial treatment for dysphagia. OBJECTIVE: To investigate the effect of resistance EMST on the swallowing function in stroke patients with oropharyngeal dysphagia. METHODS: Forty-two stroke patients with dysphagia were randomly assigned to two groups: an experimental group (n = 13) and a placebo group (n = 13). The experimental group performed EMST using a portable EMST device, while the placebo group performed EMST using a sham EMST device with no loading. The intervention was performed 5 days per week for 4weeks, in five sets of 5 breaths through the device for a total of 25 breaths per day. Both groups underwent conventional dysphagia treatment for 30 minutes/day, 5 days/week, for 4 weeks. Videofluoroscopic dysphagia scale (VDS) and penetration-aspiration scale (PAS) based on a videofluoroscopic swallowing study (VFSS) were assessed to analyze the oropharyngeal swallowing function. RESULTS: The experimental group showed more improvement in pharyngeal phase of the VDS (p = 0.018 and 0.006, respectively) and PAS compared to the placebo group (p = 0.014). CONCLUSIONS: We suggest that EMST could improve the effects of dysphagia observed in post-stroke elderly patients based on swallowing function.

Effect of neuromuscular electrical stimulation on lip strength and closure function in patients with dysphagia after stroke.

[Purpose] This study aimed to investigate the effect of neuromuscular electrical stimulation (NMES) on lip strength and closure function of patients with dysphagia after stroke. [Subjects and Methods] Eight patients with dysphagia were recruited. NMES was applied to the orbicularis oris muscle. All the participants received NMES for 30 min/d, 5 d/wk, for 4 weeks. Lip strength was measured using the Iowa Oral Performance Instrument. To assess lip closure, the lip closure subitem of the videofluoroscopic dysphagia scale was used. [Results] Lip strength showed significant improvement and lip closure function showed a significant decrease. [Conclusion] This study demonstrates that NMES is useful for improving lip strength and closure function.

Effects of bedside self-exercise on oropharyngeal swallowing function in stroke patients with dysphagia: a pilot study.

[Purpose] The purpose of this study was to investigate the effect of self-exercise on oropharyngeal swallowing function in patients with dysphagia. [Subjects and Methods] Nine patients with dysphagia after stroke were recruited. Self-exercise including effortful swallowing, tongue strengthening, and shaker exercise was performed 5 times a week for 4 weeks. Swallowing function was evaluated using the videofluoroscopic dysphagia scale (VDS) based on a videofluoroscopic swallowing study. [Results] There were significant differences in both the oral and pharyngeal phases of the VDS before and after the intervention. [Conclusion] This study demonstrated that bedside self-exercise is a positive method to improve oropharyngeal swallowing function in patients with dysphagia after stroke.