HA-treated Group Research Articles

Unveiling the Multi-Targeted Mode of Action: Investigating the Antiepileptic Activity of Murraya koengii Extract in PTZ-induced Seizures.

Recurrent seizures are the hallmark of the neurological condition known as epilepsy. Murraya koenigii (curry leaves) has been traditionally used in medicine for various ailments. This study aimed at the anticonvulsant activity of HAEMK using a petylenetetrazole (PTZ) induced seizure model. Behavioral and biochemical parameters were assessed to determine the effectiveness of the extract in mitigating seizures. Albino mice were orally administered with different doses of the extract prior to PTZ administration. The behavioral parameters, including seizure latency, duration and severity, were monitored and recorded. Additionally, acetylcholine esterase, GSH, and malondialdehyde (MDA), three indicators of oxidative stress, were assessed in brain tissue homogenates. HAEMK-treated groups demonstrated a substantial increase in seizure latency and a decrease in seizure length and intensity compared to the control group. A dose-dependent MDA and acetylcholine esterase decreased concurrent GSH rise were seen in the HA-treated groups. These findings suggest that the hydroalcoholic extract of M. koenigii possesses antiepileptic activity, possibly mediated through its antioxidative mechanisms.

Humic Acid Alleviates the Toxicity of Nanoplastics towards Solanum lycopersicum

Nanoplastics (NPs) are emerging pollutants that contaminate agricultural produce. The present study investigates the impact of polystyrene (PS) and humic acid (HA) individually and in combination on the germination and growth of seeds of Solanum lycopersicum (tomato). Here we report the formation of eco-corona upon the interaction of PS with humic acid at 24 h with a significant increase in hydrodynamic size. Seed germination, plant growth, and chlorophyll content increased in the coronated PS. In addition, we report that the treatment of seeds with PS + HA resulted in the germination of 90% of seeds, while treatment with only PS resulted in the germination of only 65.8% of seeds. A quantitative analysis of chlorophyll (a, b, and a + b) revealed that HA-treated groups and PS + HA-treated groups showed significantly high chlorophyll (a, b, and a + b) contents of (PS: 3.48 mg g−1, 2.12 mg g−1, and 4.19 mg g−1, HA: 5.76 mg g−1, 3.88 mg g−1, and 6.41 mg g−1, PS + HA: 4.17 mg g−1, 3.23 mg g−1, and 6.58 mg g−1)respectively compared to PS treated groups. Similarly, ROS levels were comparatively low in HA and PS + HA-treated groups than in only-PS-treated groups. Furthermore, we observed a decline in the level of antioxidant enzyme (superoxide dismutase and catalase) activity in HA and PS + HA treated groups than that in only-PS treated groups. The results indicate that HA significantly reduces PS-induced toxicity and improves germination and growth of seeds of Solanum lycopersicum; the corresponding reduction in toxic effects may be due to eco-corona formation on the PS. We understand that eco-corona is a way to protect plants from xenobiotics concerning nanoplastics.

The Effect of Humic Acid and Polystyrene Fluorescence Nanoplastics on Solanum lycopersicum Environmental Behavior and Phytotoxicity.

The impacts of nanoplastics (100 nm) on terrestrial systems are unclear at this time. Due to the utilization of sewage sludge, plastic particles are likely to accumulate in these systems. The current research investigates how Solanum lycopersicum seed germination and growth are affected by fluorescence polystyrene (Flu-PS), humic acid (HA), and a Flu-PS+HA combination (tomato). Following 24 h of interaction between Flu-PS and HA, our report details the development of an eco-corona with a significant increase in hydrodynamic size. Plant growth, seed germination, and chlorophyll content were all enhanced by the eco-coronated Flu-PS.Additionally, we discover that seeds treated with Flu-PS+HA demonstrated a germination rate of 90%, compared to just 65.8% for seeds treated with Flu-PS alone. Chlorophyll (a, b, and a + b) content measurements indicated that HA-treated groups and Flu-PS+HA-treated groups had considerably higher levels of chlorophyll (a, b, and a + b) than Flu-PS-treated groups (Flu-PS: 3.18 mg g-1, 2.12 mg g-1, and 3.89 mg g-1, HA: 5.96 mg g-1, 4.28 mg g-1, and 6.36 mg g-1, and Flu-PS+HA: 4.17 mg g-1, 3.01 mg g-1, and 6.08 mg g-1, respectively). In a similar manner, the HA and Flu-PS+HA treatment groups showed lower ROS levels than the Flu-PS treatment groups. In addition, we discovered that the activity of the antioxidant enzymes superoxide dismutase and catalase was lower in the groups treated with HA and Flu-PS+HA than in the groups solely treated with Flu-PS. The results demonstrated that HA significantly lessens the toxicity caused by Flu-PS, while also promoting the germination and growth of Solanum lycopersicum seeds. The related decrease in toxic effects may be ascribed to the establishment of an eco-corona on the Flu-PS. We think that the use of eco-coronas is a technique for safeguarding plants against xenobiotics such as nanoplastics.

A Comparative Study of Platelet-Rich Fibrin and Platelet-Rich Fibrin with Hydroxyapatite to Promote Healing of Impacted Mandibular Third Molar Socket.

The purpose of this study was to compare the efficacy of platelet-rich fibrin (PRF) and platelet-rich fibrin (PRF) with hydroxyapatite (HA) on postoperative pain, swelling, soft tissue healing and osseous regeneration in mandibular third molar extraction socket in human patient. This prospective study included total 40 patients who reported to the Department of Oral and Maxillofacial Surgery (OMFS), Teerthanker Mahaveer Dental College and Research Centre (TMDC&RC), Moradabad (U.P.). Twenty patients each in both the groups of PRF and PRF with HA were included for the management of impacted mandibular 3rd molar extraction sockets and were evaluated for effectiveness. Evaluation was done on the basis of following parameters pain and swelling at time interval of 1st, 3rd, 7th day, soft tissue healing at time interval of 3rd, 7th, 14th day and osseous regeneration at time intervals of 1st, 3rd, 6th month postoperatively. Pain and swelling were less in the PRF with HA group when compared to PRF group. Soft tissue healing was better in the PRF with HA group compared to the PRF group. The result of the study shows rapid bone regeneration in the extraction socket treated with the PRF with HA group when compared with the PRF group. Also there was less postoperative discomfort in the PRF with HA-treated group. PRF a mitogenic promoter together with a bone graft forms a scaffolding, promotes early healing thus being creating beneficial for the patient and is also economic.

Productive performance, lipid profile and caecum microbial counts of growing rabbits treated with humic acid.

The aim of the present study was to evaluate the effect of a humic acid (HA)-supplemented diet on productive performance and some physiological parameters of growing rabbits. A total of 80 weaned V-line rabbits at an age of 4weeks were randomly divided into four groups. Rabbits of groups 2, 3 and 4 were fed diet containing 35 (HA35), 70 (HA70) and 105 (HA105) mg Humic acid/kg diet while the first group served as control (HA0). Body weight gain was positively affected by HA treatment. HA105 rabbits had the improved feed conversion value. HA treatments had significantly reduced plasma cholesterol concentration and significant increased red blood cells, white blood cells count and plasma high-density lipoprotein concentrations. However, serum aspartate amino transferase and alanine amino transferase activities, creatinine and the apparent nutrients digestibility values were not affected by HA treatments. Organic matter digestibility of all HA-treated groups significantly increased compared with HA0. At 63days of age (after 35days of treatment), caecum microbial counts decreased (total bacteria and Escherichia coli) with HA treatments. Generally HA could be considered as a biological as growth promoter feed additive alternative to antibiotics.

Efficacy of Intra-Articular Polynucleotides Associated With Hyaluronic Acid Versus Hyaluronic Acid Alone in the Treatment of Knee Osteoarthritis: A Randomized, Double-Blind, Controlled Clinical Trial.

Pain and range of motion loss are the main clinical features of osteoarthritis (OA). Hyaluronic acid (HA) is one of the infiltrative therapies for OA treatment; however, its effectiveness is a matter of an ongoing debate in clinical practice. Polynucleotides (PNs), a DNA-derived macromolecule with natural origin and trophic activity, were found to favor cell growth and collagen production, in preclinical and clinical studies regarding cartilage regeneration. This study aimed at evaluating whether injection of PNs, in combination with HA [PNs associated with HA (PNHA)], can ameliorate pain and function of knees affected by OA, more than HA alone. A randomized, double-blind, controlled clinical trial. The study enrolled 100 patients, then randomized to receive PNHA or HA alone (3 weekly knee I.A. injections). Pain reduction, decrease of proinflammatory synovial fluid (SF) factors, and improvement in knee function were evaluated by Knee Society Score and WOMAC scores, after 2, 6, and 12 months and by biochemical and immunoenzymatic analyses of SF at the end of the treatment. Knee Society Score total score and pain item significantly ameliorated in both groups, showing better results in PNHA- than in the HA-treated group. A significant reduction in the WOMAC score was observed over time for both groups. No significant adverse events were reported in either group. These findings suggest that I.A. injection of PNs, in combination with HA, is more effective in improving knee function and pain, in a joint affected by OA, compared with HA alone.

4-Hydroxycinnamic acid protects mice from cigarette smoke-induced pulmonary inflammation via MAPK pathways

Cigarette smoke (CS) is the main etiological cause of chronic obstructive pulmonary disease, the prevalence of which has continuously increased in recent years. 4-Hydroxycinnamic acid (HA) is a plant phenolic acid that has anti-inflammatory activities. In this study, we explored the therapeutic effects of HA on airway inflammation caused by CS and lipopolysaccharide (LPS) in mice. The animals received 1 h of CS exposure for 7 days and intranasal instillation of LPS on day 4. HA (10 and 20 mg/kg) was administered to animals via oral gavage 1 h before CS exposure. HA treatment significantly decreased the accumulation of inflammatory cells and production of cytokines, including tumor necrosis factor-α, interleukin (IL)-6, and IL-1β, caused by CS and LPS exposure. After histological examination, we observed that HA treatment significantly reduced the infiltration of inflammatory cells into lung tissue caused by CS and LPS exposure. Furthermore, HA-treated groups showed significantly decreased phosphorylation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, and nuclear factor-κB, and activity of cytochrome c oxidase subunit-2 caused by CS and LPS. In conclusion, HA effectively suppresses the airway inflammatory response induced by CS and LPS exposure, and is closely associated with the downregulation of mitogen-activated protein kinases signaling.

A pilot clinical trial to determine the safety and efficacy of aerosolized hyaluronan as a treatment for COPD.

A novel therapy for COPD involving the use of aerosolized hyaluronan (HA) was tested on a small cohort of COPD patients to determine both its safety and efficacy in reducing levels of desmosine and isodesmosine (DID), biomarkers for elastin degradation. In a 2-week, randomized, double-blind trial, 8 patients receiving 150 kDa HA (mean molecular weight) and 3 others given placebo did not show significant adverse effects with regard to spirometry, electrocardiograms, and hematological indices. Furthermore, measurements of DID in plasma from HA-treated patients indicated a progressive decrease over a 3-week period following initiation of treatment (r=−0.98; p=0.02), whereas patients receiving placebo showed no reduction in DID (r=−0.70; p=0.30). Measurements of sputum in the HA-treated group also revealed a progressive decrease in DID (r=−0.97; p=0.03), but this finding was limited by the absence of similar measurements in the placebo group. Nevertheless, the results of this small, pilot study support a longer-term trial of HA in a larger population of COPD patients.

Hyaluronan Nanoparticles Selectively Target Plaque-Associated Macrophages and Improve Plaque Stability in Atherosclerosis.

Hyaluronan is a biologically active polymer, which can be formulated into nanoparticles. In our study, we aimed to probe atherosclerosis-associated inflammation by using hyaluronan nanoparticles and to determine whether they can ameliorate atherosclerosis. Hyaluronan nanoparticles (HA-NPs) were prepared by reacting amine-functionalized oligomeric hyaluronan (HA) with cholanic ester and labeled with a fluorescent or radioactive label. HA-NPs were characterized in vitro by several advanced microscopy methods. The targeting properties and biodistribution of HA-NPs were studied in apoe–/– mice, which received either fluorescent or radiolabeled HA-NPs and were examined ex vivo by flow cytometry or nuclear techniques. Furthermore, three atherosclerotic rabbits received 89Zr-HA-NPs and were imaged by PET/MRI. The therapeutic effects of HA-NPs were studied in apoe–/– mice, which received weekly doses of 50 mg/kg HA-NPs during a 12-week high-fat diet feeding period. Hydrated HA-NPs were ca. 90 nm in diameter and displayed very stable morphology under hydrolysis conditions. Flow cytometry revealed a 6- to 40-fold higher uptake of Cy7-HA-NPs by aortic macrophages compared to normal tissue macrophages. Interestingly, both local and systemic HA-NP–immune cell interactions significantly decreased over the disease progression. 89Zr-HA-NPs-induced radioactivity in atherosclerotic aortas was 30% higher than in wild-type controls. PET imaging of rabbits revealed 6-fold higher standardized uptake values compared to the muscle. The plaques of HA-NP-treated mice contained 30% fewer macrophages compared to control and free HA-treated group. In conclusion, we show favorable targeting properties of HA-NPs, which can be exploited for PET imaging of atherosclerosis-associated inflammation. Furthermore, we demonstrate the anti-inflammatory effects of HA-NPs in atherosclerosis.

The Wound Healing Effects of Adiponectin Eye Drops after Corneal Alkali Burn

ABSTRACTPurpose: To investigate the wound healing effect of adiponectin eye drops following corneal alkali burn.Materials and Methods: A chemical burn was induced using 0.1 M NaOH in both adenovirus 12-SV40 hybrid-transformed human corneal epithelial (HCE-2) cells and C57BL/6 mice. The injured HCE-2 and mice were then treated using either 0.1% hyaluronic acid (HA) or adiponectin at 0.0001%, 0.001%, or 0.01% concentration. The viability of the HCE-2 cells was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The wound healing rate of the HCE-2 cells was evaluated using a migration assay 4, 8, 12, 24, and 48 h after chemical injury. In mice, corneal epithelial defects and degree of haze were analyzed 6 h and 1, 2, 3, 6, and 7 days after chemical injury. Seven days after injury, the concentrations of IL-1β and transforming growth factor-β (TGF-β) in the cornea were measured using enzyme-linked immunosorbent assay, and histological analysis was also performed.Results: The viability of HCE-2 cells was not affected by adiponectin at any of the concentrations used. In HCE-2 cells treated using either 0.001% or 0.01% adiponectin, the wound healing rate after 4 h was significantly faster than in the control and HA-treated groups. With regard to mice, the 0.001% and 0.01% adiponectin-treated groups showed a significant improvement in epithelial defect parameters and haze scores at 3, 5, and 7 days after chemical injury. A significant decrease in IL-1β and TGF-β levels was observed in the 0.001% and 0.01% adiponectin-treated groups compared to the other groups. Histologically, corneal thickness and the inflammatory cells were also decreased in the adiponectin-treated groups.Conclusions: Topical adiponectin (both 0.001% and 0.01%) increased epithelial migration and improved clinical signs and inflammation on the ocular surface after alkali burn, suggesting that adiponectin can promote wound healing in the cornea.

Effect effects of <i>Auricularia auricula</i> polysaccharides on exhaustive swimming exercise-induced oxidative stress in mice

Purpose: To determine the effects of polysaccharides from Auricularia auricula (AAPs) on exerciseinduced oxidative stress in mice.Methods: The animals were divided into four groups: control (C), low, middle, and high-dose AAPstreated (LA, MA, and HA, respectively). C group received physiological saline solution while AAPstreated groups received different doses of AAPs (50, 100, and 200 mg/kg) via oral gavage once a day for 28 days, followed by an exhaustive swimming exercise. Swimming times were recorded for each animal after which malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) were determined.Results: Exhaustive swimming times were significantly prolonged in all AAPs-treated animals as compared with controls. In all treatment groups, serum and muscle MDA levels were significantly lower than those in the C group, whereas in the MA- and HA-treated groups, a decrease was also seen for liver MDA levels. Furthermore, the concentration of 8-OHdG was significantly reduced in serum, liver, and muscle in all AAPs-treated animals. In contrast, all AAPs treatment groups exhibited significantly higher SOD activity in serum, liver, and muscle. Serum and liver GPx activity was also significantly increased in all animals receiving AAPs treatment, with MA- and HA-treated mice exhibiting an additional augmented GPx activity in muscle. Serum and liver catalase activities in the MA and HAtreated groups, and catalase activity in muscle in all AAPs treatment cohorts, were significantly higher.Conclusion: Polysaccharides from Auricularia auricula enhance exercise endurance and possess protective effects against exhaustive swimming exercise-induced oxidative stress in mice.Keywords: Exhaustive swimming, Malondialdehyde, 8-Hydroxydeoxyguanosine, Superoxide dismutase, Glutathione peroxidase, Catalase

Retraction Note: Volume therapy in the critically ill: is there a difference?

Objective: There are still several concerns about the extensive and prolonged use of hydroxyethylstarch solution (HES) in critically ill patients. The effects of volume replacement with HES over 5 days on hemodynamics, laboratory data, and organ function were compared with volume therapy using human albumin (HA). Design: Prospective, randomized study. Setting: Clinical investigations on a surgical intensive care unit (ICU) of a university hospital. Patients: 150 traumatized patients (injury severity score > 15) and 150 postoperative patients with sepsis were analyzed. Interventions: Either 10 % low-molecular weight HES (HES-trauma, n = 75; HES-sepsis, n = 75) or 20 % HA (HA-trauma, n = 75; HA-sepsis, n = 75) was given for 5 days to maintain the pulmonary capillary wedge pressure (PCWP) between 12 and 15 torr. The entire management of therapy of the patients was performed by physicians who were not involved in the study and blinded to the infusion regimen. Measurements and results: In addition to extensive cardiorespiratory monitoring, several routine laboratory parameters for assessing pulmonary, renal, hepatic, and coagulation function were analyzed from arterial blood samples on the day of admission to the ICU and on the day of sepsis diagnosis, respectively (“baseline” value) and daily over the following 5 days. Mortality during and after the study did not differ significantly between the infusion groups. There were also no differences between the incidence of pulmonary, renal, or hepatic failure in the two subgroups. Mean arterial pressure, heart rate, and PCWP were similar in both subgroups, whereas cardiac index, oxygen delivery index, oxygen consumption index, and the ratio between the partial pressure of oxygen in arterial blood and fractional inspired oxygen were higher in the HES- than in the HA-treated groups. Standard coagulation parameters did not differ, albumin concentration increased significantly in both HA groups, and lactate concentrations decreased only in the HES-sepsis patients (from 2.8 ± 0.5 to 1.5 ± 0.4 mg/dl). Volume replacement using albumin was significantly (p < 0.001) more costly than therapy with HES. Conclusions: Volume therapy with 10 % HES for 5 days in the ICU patient showed no disadvantages compared with an infusion regimen using 20 % albumin. Volume replacement using HES may even be associated with improved hemodynamics. HES appears to be a valuable and significantly cheaper alternative to albumin – even for prolonged volume therapy in the critically ill patient.

“Functional Pain,” Functional Outcomes, and Quality of Life After Hyaluronic Acid Intra-articular Injection for Knee Osteoarthritis

To compare the effect of hyaluronic acid (HA) intra-articular knee injections on pain and functional outcomes in persons with knee osteoarthritis (OA) over 6 months, and to determine whether or not changes in functional pain are related to improvements in quality of life. A prospective cohort study. A research laboratory in an academic medical center. Patients with knee OA (N = 53) who were receiving medical care for OA. Intra-articular knee injections of HA (3 injections, each separated by 1 week) and a comparative noninjection group. Functional pain and outcomes assessments during chair rise, stair climbing, and a 6-minute walking test (by using 0-10 point numerical pain ratings during each test); gait parameters; Medical Outcomes Short Form-36 (SF-36) scores and subscores; the Western Ontario McMaster University Osteoarthritis Index (WOMAC). Six months after HA, the completion times for the chair rise and stair climb tasks, and the distance covered during the 6-minute walk were not different between the groups. However, functional pain ratings during stair climbing decreased in the HA-treated group (P = .05). Six-month changes in gait velocity, cadence, stride length, step length, and the percentage of the gait cycle spent in single support were all higher after HA injection at month 6 (all P < .05). Significant group-by-time interactions existed for total WOMAC scores. SF-36 Vitality subscores improved by 13%, and Role Physical scores were higher in patients treated with HA injection compared with participants in the noninjection group (P < .05). Regression analyses revealed that changes in the functional pain measures did not correspond with SF-36 scores. HA is associated with lower functional pain severity, with minimal impact on functional test scores. We interpreted this finding to represent an increase in the quality of the movement and functional activity. The change in functional pain did not correspond to changes in SF-36 quality-of-life scores.

Combined Effect of Subchondral Drilling and Hyaluronic Acid with/without Diacerein in Full-Thickness Articular Cartilage Lesion in Rabbits

The osteochondral healing potential of hyaluronic acid (HA) plus diacerein was evaluated in subchondral-drilling- (SCD-) induced fibrocartilage generation in rabbits. A full-thickness chondral defect was created along the patellar groove of both knees and then SCD was subsequently performed only in the left knee. A week later, the rabbits were allocated into 3 groups to receive weekly intra-articular (IA) injection for 5 weeks with normal saline solution (NSS) (group 1) or with HA (group 2 and group 3). Starting at the first IA injection, rabbits were also gavaged daily for 9 weeks with NSS (group 1 and group 2) or with diacerein (group 3). The animals were then sacrificed for evaluation. The newly formed tissue in SCD lesions showed significantly better histological grading scale and had higher content of type II collagen in HA-treated group compared to NSS control. In addition, adding oral diacerein to HA injection enhanced healing potential of HA.

In vitro effects of sodium hyaluronate on the proliferation and the apoptosis in chondrocytes from patients with Kashin-Beck disease and osteoarthritis

Objective To identify the in vitro effects of sodium hyaluronate(HA) on the proliferation and the apoptosis of chondrocytes from patients with Kashin-Beck disease(KBD) and osteoarthritis(OA). Methods Samples of articular cartilages from KBD and OA patients, as well as healthy volunteers(6 subjects in each of the 3 groups) were dissected, digested with collagenase and the cells cultured in monolayers. Chondrocytes from each sample were assigned to an untreated group and two HA-treated groups: H0(no HA), H100(HA, 0.1 g/L) and H500(HA, 0.5 g/L). The first passage chondrocytes were used to observe proliferation using the MTT assay, and apoptosis by flow cytometry through Annexin V/PI staining. Results HA promoted proliferation of chondrocytes in all the three groups, and in KBD and OA groups, for cells cultured for 4 and 6 days, H500 significantly promoted the cell proliferation. The apoptotic rates of both KBD and OA group chondrocytes were in the order H500 < HA100 < H0. Conclusion Sodium hyaluronate administration has a dose-dependent in vitro effect to promote proliferation and inhibit apoptosis of chondrocytes from patients with KBD and OA.

Transient benefits for topical hyaluronic acid in recurrent aphthous ulceration

A randomised controlled trial. A topical application of 0.2% hyaluronic acid (HA) gel or placebo was initially applied by a clinician to the ulcerated area. Patients were instructed how to apply gel for subsequent applications. Patients recorded discomfort from the ulcerated area on a 100-mm visual analogue scale (VAS). The boundaries of the scale were marked "no soreness" and "worst possible soreness". Recordings were made at baseline (before gel application) and at 5, 10, 15, 20, 30, 45, 60, 120, 180 and 240 min after dosing. The first 60 min of the recording were supervised and the remaining observations were carried out in a log diary. Discomfort recordings were made 1 h after application (after breakfast and after the evening meal and at one other time if desired) for 7 days. Patients were also asked to record number of ulcers present in their mouth and the occurrence of any new ulcers during the treatment period. Both topical HA and placebo resulted in a significant reduction in ulcer soreness following immediate application (P 0.0004). Throughout the rest of the investigation period, there were no significant differences (P>0.05) between the treatments at reducing soreness. Patients using topical HA recorded fewer ulcers on day 5 of the investigation than those in the placebo group (P<0.001). Likewise, the occurrence of new ulcers was lower in the HA-treated group on day 4 compared with placebo (P 0.047). Topical application of 0.2% HA does appear to be of benefit in the management of recurrent aphthous ulceration (RAS). Immediate application reduces discomfort but this is purely a barrier or protective mechanism from stimuli arising in the oral environment.

Effectiveness of MeroGel hyaluronic acid on tympanic membrane perforations

Conclusions. Our results support the proposition that hyaluronic acid (HA) provides a moist wound-healing environment to aid in the healing process of tympanic membrane perforation. A single MeroGel administration can be effective as well as daily topical HA application in the treatment of tympanic membrane perforations. A single application of esterified HA may be more suitable for patients and also for otolaryngologists. Objective. The purpose of the present study was to evaluate the effectiveness of a single MeroGel application on traumatic tympanic membrane perforations in rats. Materials and methods. The posterior quadrant of the tympanic membranes in both ears of 24 male pathogen-free Sprague-Dawley rats was perforated with a 20-gauge needle. Subjects were divided into two groups: MeroGel and daily topical HA-treated groups. All subjects were sacrificed and histopathological examinations of the tympanic bullas were carried out. Results. Perforations of controls, and MeroGel- and daily HA-treated groups closed in 17/24 (70.8%), 11/12 (91.7%), and 12/12 (100%) ears, respectively. There was a significant difference between control and MeroGel-treated groups, and also between control and daily topical HA-treated groups for the presence of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), lymphocytes and collagen fibrils (p<0.05), whereas there was no significant difference between MeroGel- and daily topical HA-treated groups (p>0.05).

The effects of carboxymethylated chitosan on metalloproteinase-1, −3 and tissue inhibitor of metalloproteinase-1 gene expression in cartilage of experimental osteoarthritis

The aim of this study was to evaluate the effects of intra-articular injection of carboxymethylated chitosan (CMCTS) on mRNA expression of matrix metalloproteinase-1, -3 (MMP-1, -3) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in cartilage of osteoarthritis (OA). 32 white rabbits underwent unilateral anterior cruciate ligament transection (ACLT) and were randomly divided into four groups 5 weeks after transection. Rabbits of group A received 0.3 ml intra-articular injection of 2% high molecular weight CMCTS, once 2 weeks. Rabbits in group B were treated under the same condition using 2% CMCTS with low molecular weight. Group C rabbits received 0.3 ml of intra-articular 1% sodium hyaluronate (HA) injection, once a week. Animals of group D were not injected as controls after ACLT. At death, 11 weeks following surgery, the mRNA expressions of MMP-1, MMP-3 and TIMP-1 of degenerative cartilage were analyzed using reverse transcription-polymerase chain reaction. The mRNA levels of MMP-1 and MMP-3 in cartilage of CMCTS injection groups were significantly lower than those of HA-treated group and untreated group. There was no significant difference in MMP-1 and MMP-3 expression between the different molecular weight CMCTS injection groups. No significant difference in MMP-1 and MMP-3 expression in cartilage was found between HA injection group and control group. No significant difference in TIMP-1 expression was observed in cartilages of any group. CMCTS may significantly suppress the mRNA expression of MMP-1 and MMP-3 in cartilage during the early stages of OA. CMCTS may have a protective effect on articular cartilage of OA.

Effects of hyaluronan on three-dimensional microarchitecture of subchondral bone tissues in guinea pig primary osteoarthrosis

Hyaluronan (HA) has received increasing interest as a potential agent in therapeutic intervention in osteoarthrosis (OA). HA has been shown to reduce arthritic lesions in experimental animal models of articular cartilage injury. This study was to investigate the effects of high molecular weight HA intra-articular injection on subchondral bone tissues. Fifty-six male guinea pigs were randomly divided into 5 groups. During the initial 2.5-month period, three groups received intra-articular injection of HA 0.4 mg/kg/week for 5 weeks in both knee joints. Two control groups received vehicle. After 2.5 months, one HA group and one control group were sacrificed. The remaining 3 groups (5.5-month groups) were left for an additional 3 months before sacrifice during which time one HA group received additional 5 weeks injections, one HA group received no more injections, and the control group received vehicle. The left tibiae were harvested and micro-CT scanned to quantify three-dimensional microarchitecture of subchondral bone plate, cancellous bone and cortical bone, followed by mechanical testing and collagen and mineral determinations. All HA-treated groups had almost normal cartilage, whereas the control groups had typical OA-related cartilage degradation. In the 2.5-month group, HA resulted in significantly decreased subchondral plate volume fraction and thickness and HA-treated cancellous bone had significantly lower bone volume fraction, and typical rod-like structure. After 5.5 months, these changes were more pronounced, with an additional marked decrease in connectivity and bone surface density. HA-treated cortical bone had significantly greater volume fraction at both observation times. HA groups had greater bone mineral concentration and reduced collagen to mineral ratio with similar mechanical properties of cancellous bone but less stiff cortical bone. The effects of HA on cartilage and subchondral bone were maintained when treatment was discontinued. In summary, HA effectively protects against cartilage degeneration, decreases subchondral bone density and thickness, changes trabecular structure toward rod-like, so that subchondral bone becomes more compliant and thereby reduces cartilage stress during impact loading. HA preserved cancellous bone mechanical properties by increasing bone mineralization. Early HA administration is effective for intervention of OA initiation and progression, and short-term early HA treatment is sufficient to maintain treatment effects.

The effect of hyaluronic acid on tracheal wound healing

Problem: Various methods have been studied to improve tracheal healing after surgery. Previous experiments have demonstrated the benefits of hyaluronic acid (HA) not only in wound healing in the tympanic membrane, skin, and articular cartilage but also in decreasing adhesions in abdominal operations. The goal of this project was to study the effects of hyaluronic acid on tracheal wound healing. Methods: Twenty-two New Zealand white rabbits, (11 experimental, 11 control) had a 2 mm round defect created in the third tracheal ring. The experimental group had an 8 mm round sodium hyaluronate-based sponge (SEPRAPACK™) fixed over the defect using fibrin glue (Hemaseel™). The control group had a plain 8 mm collagen sponge placed in a similar manner. Tracheal tissue was harvested at 4 weeks postop and histologically scored in regard to inflammation, connective tissue organization, epithelial closure, chondrocyte death, and cartilage regeneration (clonal cell formation) at the area of injury. Statistical analysis was done using the Mann-Whitney U and Fisher-Exact tests. Results: Inflammatory cell infiltration was significantly increased at the area of injury in the control group compared to the HA-treated wound ( P = 0.014). In the HA-treated group a lower percentage of animals had chondrocyte death at the wound edge (45.5%-HA vs 81.8%-control) ( P = 0.183) and a greater percentage of animals demonstrated new clonal cell formation (72.7%-HA vs 54.5%-control) ( P = 0.659). No differences were seen in connective tissue organization and epithelial closure. Conclusion: These results show that HA significantly decreases inflammation in tracheal wounds in a rabbit model. Although not statistically significant, the results also suggest that HA may be chondroprotective, as demonstrated in articular cartilage models. Significance: Poor wound healing including cartilage ring damage can contribute to airway compromise especially in an infant after tracheal surgery. This experiment suggests that HA may be useful as an adjunct in improving postoperative tracheal repair. Support: (1) The Friedberg Research Fund in the Department of Otolaryngology at Rush University Medical Center. (2) SEPRAPACK ™ and Hemaseel ™ were both donated by GYRUS ENT and HAEMACURE, respectively under no obligation by the authors.