Topical Administration of Carvacrol Improves Healing in Nasal Septal Perforation: An Experimental Animal Study

BACKGROUND

Clinicians are exploring alternative treatments for nasal septum perforation since surgical treatment is challenging.

OBJECTIVE

The effects of topical carvacrol on the healing of nasal septal perforation were investigated in an animal model.

METHOD

Twenty-one male New Zealand rabbits were randomly divided into three equal groups. A 5-mm circular biopsy punch was used to perforate the nasal septum behind the columella. For 14 days, bilateral gelatin sponges impregnated with carvacrol in olive oil in group 1, and only olive oil in group 2 were placed. Perforation only was performed in the control group. Animals were then sacrificed, and their nasal septums were removed. The closure of the perforation was measured, and samples were examined histopathologically. MMP-9 reactivity was evaluated using the immunoperoxidase technique. Histopathologic parameters were scored as 0 = none, 1 = mild, 2 = moderate, and 3 = strong.

RESULTS

The septum perforation closure in the carvacrol group was statistically significant compared with the other groups (p < 0.001). Cartilage regeneration, connective tissue density, and MMP-9 immunoreactivity were significantly higher in the carvacrol group (p = 0.020, p = 0.009, and p = 0.008, respectively).

CONCLUSION

Topically administered carvacrol enhances wound healing in rabbit nasal septum perforation. It accelerated perforation closure by increasing cartilage regeneration, connective tissue, and MMP-9 expression.

The ocular pyogranulomatous lesion in a Gentoo penguin (Pygoscelis papua) from the Antarctic Peninsula: evaluation of microbiological and histopathological analysis outcomes

In this study, it was aimed to present the results of microbiological, cytological, histopathological, and immunohistochemical analyses of ocular samples from an Antarctic (Ardley Island, King George Island) Gentoo penguin chick (Pygoscelis papua) with a pyogranulomatous lesion in the right eye. Samples were taken from both the healthy left eye and the lesion in the right eye. Conventional culture methods and phenotypic and molecular tests were used for bacterial isolation and identification, respectively. None of the isolates could be identified phenotypically. As a result, four of the five isolates obtained from the right eye were considered to belong to putative novel bacterial species and taxa as their similarity to GenBank data was below 98.75%. The isolates were considered to be Pasteurellaceae bacterium, Corynebacterium ciconiae, Cardiobacteriaceae bacterium, Actinomyces sp., and Dermabacteraceae bacterium. The only isolate from the left eye was identified as Psychrobacter pygoscelis. The cytological analysis demonstrated cell infiltrates composed mostly of degenerate heterophils, reactive macrophages, plasma cells, lymphocytes, and eosinophils. Based on histopathological findings, the lesion was defined as a typical pyogranulomatous lesion. Immunohistochemistry demonstrated that the granuloma was positive for TNF-α, IL-4, MMP-9, IL-1β, and IL-6. This is the first documented report of the unilateral pyogranulomatous ocular lesion in a Gentoo penguin chick, living in its natural habitat in Antarctica. This report also describes the isolation of four bacteria from the infected eye, which are considered to belong to novel Genus, species, or taxa. The primary bacterial pathogen that caused the ocular lesion was not able to be detected and remains unclear.

Idebenone Ameliorates Rotenone-Induced Parkinson's Disease in Rats Through Decreasing Lipid Peroxidation

Oxidative stress is considered one of the mechanisms responsible for neurodegenerative diseases, especially for Parkinson's disease. Since oxidative stress causes pathological changes in neuronal structures antioxidant compounds gained significant attention the last decades. Although several antioxidant compounds showed neuroprotective actions in Parkinson's disease models, only a few of them demonstrated protective effects against loss of striatal dopaminergic neurons. Idebenone is an analog of the well-known antioxidant compound coenzyme Q10 (CoQ10). Clinical safety of idebenone is well described, and due to its high antioxidant capacity currently used to treat Freidrich's ataxia and Alzheimer's disease. Like Parkinson's disease, these diseases are characterized by oxidative stress and impaired mitochondrial balance in neurons. However, knowledge about the effects of idebenone on Parkinson's disease is limited. Therefore, in this study we aimed to investigate and delineate the possible effects of idebenone in rotenone-induced Parkinson's disease models. Idebenone (200 mg/kg, p.o.) inhibited the decrease of striatal expression of NAD(P)H dehydrogenase[quinone]-1, which is an essential element for mitochondrial respiration. Idebenone decreased the striatal levels of the lipid peroxidation products and increased the expression of glutathione peroxidase-4 (GPx-4), which is primarily known for lipid peroxidation and ferroptosis. Furthermore, idebenone mitigated motor impairment and increased tyrosine hydroxylase-positive neuron survival. Together our results thus indicate that that idebenone has protective effects against a rotenone insult with pleiotropic actions on the cellular oxidative enzymes and lipid peroxidation.

A combination of methylprednisolone and quercetin is effective for the treatment of cardiac contusion following blunt chest trauma in rats

Cardiac contusion is a potentially fatal complication of blunt chest trauma. The effects of a combination of quercetin and methylprednisolone against trauma-induced cardiac contusion were studied. Thirty-five female Sprague-Dawley rats were divided into five groups (n=7) as follows: sham, cardiac contusion with no therapy, treated with methylprednisolone (30 mg/kg on the first day, and 3 mg/kg on the following days), treated with quercetin (50 mg·kg⁻¹·day⁻¹), and treated with a combination of methylprednisolone and quercetin. Serum troponin I (Tn-I) and tumor necrosis factor-alpha (TNF-α) levels and cardiac histopathological findings were evaluated. Tn-I and TNF-α levels were elevated after contusion (P=0.001 and P=0.001). Seven days later, Tn-I and TNF-α levels decreased in the rats treated with methylprednisolone, quercetin, and the combination of methylprednisolone and quercetin compared to the rats without therapy, but a statistical significance was found only with the combination therapy (P=0.001 and P=0.011, respectively). Histopathological degeneration and necrosis scores were statistically lower in the methylprednisolone and quercetin combination group compared to the group treated only with methylprednisolone (P=0.017 and P=0.007, respectively). However, only degeneration scores were lower in the combination therapy group compared to the group treated only with quercetin (P=0.017). Inducible nitric oxide synthase positivity scores were decreased in all treatment groups compared to the untreated groups (P=0.097, P=0.026, and P=0.004, respectively). We conclude that a combination of quercetin and methylprednisolone can be used for the specific treatment of cardiac contusion.

The evaluation of different treatment protocols for trauma-induced lung injury in rats

BACKGROUND

Lung contusion is an important factor that affects mortality and morbidity of lung injury after blunt chest trauma (BCT). The present study aims to evaluate the effectiveness of different treatment regimens on BCT-induced lung injury.

METHODS

A total of 35 Sprague Dawley rats were divided into five experimental groups (n=7): sham, control; BCT; BCT + MP, BCT group treated with methylprednisolone (MP; 30 mg/kg on first day and 3 mg/kg/d on the following days); BCT + Q, BCT group treated with quercetin (Q; 50 mg/kg/d for seven days); and BCT + MP + Q, BCT group treated with the same doses of MP and Q. Serum Clara Cell Protein-16 (CC-16), thiobarbituric acid reactive substances (TBARS), and superoxide dismutase (SOD) levels were analyzed to determine histopathological changes in the lung tissues.

RESULTS

Elevated serum CC-16 and TBARS levels and reduced serum SOD levels were found in the BCT group compared to the Sham group. There was a significant change in the serum CC-16 levels in the BCT + MP group compared to the Sham group. Serum TBARS levels were significantly lower in the BCT + MP and BCT + Q group compared to the BCT group. The combined therapy regimen yielded significantly decreased CC-16 levels and increased serum SOD levels compared to the individual treatment groups. Serum TBARS levels did not significantly differ between the BCT + MP + Q group and the other treatment groups. Compared to the BCT + MP + Q group, the BCT + MP group showed significantly lower alveolar edema (AED) and alveolar exudate (AEX) scores, while the BCT + Q group showed significantly lower peribronchial inflammatory cell infiltration (PICI) and AED scores.

CONCLUSIONS

The combined usage of quercetin and low dose MP treatment after initial high dose MP at the early stage of lung injury after BCT is more effective.

The role of iNOS inhibitors on lung injury induced by gastrointestinal decontamination agents aspiration

Aspiration is a devastating complication during decontamination procedure in poisoning patients. We have investigated whether S-methylisothiourea protects different pulmonary aspiration gastrointestinal decontamination agent-induced lung injury in rats. Forty-two male Sprague-Dawley rats were assigned to one of six groups (n = 7): normal saline, activated charcoal, polyethylene glycol, normal saline + S-methylisothiourea treated activated charcoal + S-methylisothiourea treated and polyethylene glycol + S-methylisothiourea treated. Normal saline, activated aharcoal and polyethylene glycol were instilled into the lungs. The rats received S-methylisothiourea i.p twice daily for 7 days. Serum surfactant protein D, oxidative stress products and inducible nitric oxide synthase expression in the lung were investigated. The aspiration of activated charcoal significantly increased all histopathological scores (P < 0.01). Only peribronchial inflammatory cell infiltration, alveolar edema, and alveolar histiocytes were increased in the polyethylene glycol groups as compared to the normal saline group (P < 0.05). Pulmonary aspiration increased serum malondialdehyde (P < 0.001), and surfactant protein D (P < 0.05) levels and decreased serum superoxide dismutase levels (P < 0.05). S-methylisothiourea treatment decreased all histopathological scores in the activated charcoal treated S-methylisothiourea group (P < 0.01) and only decreased alveolar edema and alveolar histiocytes in the polyethylene glycol-treated S-methylisothiourea group (P < 0.05). S-methylisothiourea treatment reduced elevated oxidative factors, inducible nitric oxide synthase activity and serum surfactant protein D levels. Our findings showed that S-methylisothiourea may be a protective drug against Activated Charcoal and Polyethylene Glycol-induced lung injury.

Effects of polyglecaprone 25, silk and catgut suture materials on oral mucosa wound healing in diabetic rats: an evaluation of nitric oxide dynamics

OBJECTIVES

The purpose of this study is to investigate the effects of monocryl (Polyglecaprone 25), silk and catgut suture materials on wound healing in diabetic rats and to evaluate NO (nitric oxide) dynamics.

STUDY DESIGN

Fourty-eight male Wistar-Albino rats weighing 220-270 g were used in this study. The rats were categorized into 2 groups, as control group (n=24) and streptozotocin (STZ) induced diabetic group (n=24). For each group, incision wounds were created on the inner cheek mucosa of the animals and wounds were closed primarily with three different types of sutures. These materials were sized 3-0 monocryl (polyglecaprone 25), silk and catgut sutures swaged on. Excisional biopsies were performed at 2nd, 7th, 14th and 21st day (2 rats per day) from the initial surgical procedure. Effects of these suture materials on wound healing and NOS (nitric oxide synthase) activities were compared immunohistochemically in the study. eNOS and iNOS (Endothelial and induced nitric oxide synthase) activities were classified as mild (+), moderate (++) and severe (+++).

RESULTS

Mild eNOS activities were seen in both diabetic and control groups at 2nd day specimens. Activities of silk and catgut were similar both in diabetic and control groups at 14th day, this activity in monocryl was mild. 21st day specimens revealed that monocryl has mild eNOS activity than silk and catgut sutures. iNOS activities in diabetic group were greater than control groups and the degrees of the activity in monocryl, silk and catgut sutures were mild, severe and moderate at the 7th day. At the 14th day there was no iNOS activity in diabetic monocryl group.

CONCLUSION

All of the materials have the potential capacity to be well tolerated however monocryl seemed to have more beneficial effects on wound healing in diabetic subjects.

Biochemical and histopathological findings of N-Butyl-2-Cyanoacrylate in oral surgery: an experimental study

OBJECTIVES

The increasing use of cyanoacrylates in dentistry, particularly as an adhesive and sealing glue, has raised concerns regarding its potential toxicity in humans. Several different forms of these compounds including methyl- (MCA), ethyl- (ECA), isobutyl-, isohexyl-, and octyl CA have been developed to eliminate tissue toxicity. N-butyl-2-cyanoacrylate is becoming an increasingly popular method for wound closure under low tension. Despite their increasing use, pharmacologic effects of these substances on liver and kidney functions are not widely known. The objective of the present study was to investigate possible immediate and long-term systemic effects of N-butyl-2-cyanoacrylate in oral surgery.

STUDY DESIGN

Ten male Wistar rats weighing 220 to 270 g were used in the study. Straight incisions were made to the buccal mucosa of the animals. N-butyl-2-cyanoacrylate adhesive (Indermil) was applied and wounds were closed primarily. Blood specimens were taken periodically from the vena cava of the animals before the surgical procedure and 2, 14, 21, and 65 days after the surgical procedure. The blood specimens of those taken before the application of the adhesive were defined as the control group; blood specimens that were taken 2, 14, 21, and 65 days from the application were defined as study group. The stored plasma samples were analyzed for blood urea nitrogen (BUN), creatinine (CRE), alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBI), total protein (TP), albumin (ALB), and amylase (AML). In addition to biochemical parameters, histopathological examination was performed. Blood parameter values of the control and study groups were statistically compared with the Duncan test (P < .05).

RESULTS

There were no significant differences in the values of BUN, CRE, ALT, AST, TBI, TP, ALB, and AML between the control and at 2, 14, 21, and 65 days.

CONCLUSION

The present study shows that N-butyl-2-cyanoacrylate is a suitable adhesive applicable in oral surgery.

Morphological, stereological and radiological changes in pinealectomized chicken cervical vertebrae

Considerable evidence supports the hypothesis that melatonin plays an important role in osteogenesis. We carried out an experiment to investigate histological and radiological changes in the cervical vertebrae of pinealectomized chickens. Thirty new-hatched chicks were divided into two groups: pinealectomized group (n=15) and nonpinealectomized control (n=15). Surgical pinealectomies were performed in Hybro broiler chickens at the age of 3 days. At 8 wk, one animal from each group was examined using computed tomography scanner to obtain density histograms of four consecutive vertebrae between the 4th and 7th cervical vertebral segments of chickens. At the end of the study, all animals were killed for subsequent measurement of bone mineral density (BMD) and macroscopic, radiographic and histopathological evaluation of specimens. We found that the profile of the density histogram in nonpinealectomized control group showed a spike profile for the vertebral body, indicating an increase in the amount of higher density tissues in this region, while a plateau-shaped profile was obtained for the vertebral body in pinealectomy group, indicating the presence of heterogenous bone tissue. Accordingly, the mean value of BMD in pinealectomy group was significantly lower at the vertebral body in chickens compared with control subjects (P<0.001). At the end of the experiment, almost all of the chickens in pinealectomy group developed a scoliotic curvature and the mean weight and length of the cervical vertebral bodies of the pinealectomized chickens were significantly lower than those of control group (P<0.001). Although the numerical density of osteocytes and osteoblasts in pinealectomy group was significantly higher than that from the control group, total number of osteocytes but not osteoblasts in cervical vetrebrae from pinealectomized animals was significantly lower than that from nonpinealectomized control animals (P<0.05). In conclusion, the results of the current study demonstrated for the first time pinealectomy-induced histomorphometrical changes in chicken vertebral column using stereological methods, suggesting that pineal gland/melatonin may have an osteoinductive effect on bone formation, but further studies are needed to elucidate the relationship of our findings with some disorders such as postmenopausal and/or senile osteoporosis.