Comparison of Oral Sirolimus, Prednisolone, and Combination of Both in Experimentally Induced Peritoneal Adhesion

Research progress on animal models of peritoneal adhesion

Peritoneal adhesion is a common complication of abdominal and pelvic surgery that can cause various clinical symptoms, including abdominal pain, intestinal obstruction, and female infertility, significantly impacting patient quality of life. Animal models of peritoneal adhesion are important tools for studying the mechanisms of adhesion formation and evaluating the effectiveness of prevention and treatment. Various methods for constructing animal models of peritoneal adhesion include physical injury, chemical injury, ischemia, infection, foreign body stimulation, and simulated surgery; however, none can fully simulate peritoneal adhesion in patients clinically. Therefore, this review aimed to explore previous methods used to construct peritoneal adhesion animal models and summarize their principles, characteristics, and applications. Similarly, it summarizes macroscopic and microscopic evaluation indicators, such as peritoneal adhesion gross assessment, histological scoring, and molecular markers. On the basis of this, we proposed a new animal model of peritoneal adhesion that simulates the factors contributing to peritoneal adhesion formation in clinical surgery. peritoneal adhesion formation was stable and standardized using our proposed model, providing a foundation for the establishment and application of peritoneal adhesion animal models.

Effects of short-term oral letrozole on fresh semen parameters, endocrine balance, and prostate gland dimensions in domestic dogs

BACKGROUND

Aromatase inhibitors improve male fertility by modifying the hormonal control of spermatogenesis. The present study aimed to investigate the effects of oral administration of letrozole on testosterone and estradiol concentrations and their ratios in blood serum, seminal plasma, prostatic fluid, sperm quality in fresh semen, and prostate gland dimensions. Seven adult male intact mixed-breed dogs were selected. The animals received letrozole (72 µg/kg, PO) daily for four weeks. Blood samplings and semen collections were carried out on days 0 (control), 14 (treatment), 28 (treatment), and 42 (post-treatment).

RESULTS

Our results showed that letrozole administration resulted in a 4.3 fold significant increase in serum, seminal plasma, and prostatic fluid testosterone levels after 14 days. This remained high until the end of the study. Serum and prostatic fluid estradiol levels did not change significantly over the study period. However, the seminal plasma estradiol level showed a significant increase on day 14. The estradiol: testosterone ratio was significantly reduced on day 14 in serum, seminal plasma, and prostatic fluid samples. Letrozole significantly improved the ejaculated spermatozoa viability and concentration after 28 days of oral administration. However, the sperm plasma membrane functional integrity and kinematic parameters were not significantly affected by the treatment. Transabdominal ultrasound examination revealed a significant increase in the height, width, and volume of the prostate gland after 28 days of treatment.

CONCLUSIONS

According to the present research, oral administration of letrozole for 28 days affects local and systemic sex hormone balance leading to an improvement of the ejaculated canine spermatozoa viability and concentration concurrent with an increase in the prostate gland dimensions.

Effects of linalool on postoperative peritoneal adhesions in rats

The current study examines the effects of linalool in preventing postoperative abdominal adhesions. Twenty male Wistar rats were randomly divided into four groups. (1) Sham: in this group, the abdomen was approached, and without any manipulations, it was sutured. (2) Control: rats in this group underwent a surgical procedure to induce adhesions. This involved making three incisions on the right abdominal side and removing a 1×1-cm piece of the peritoneum on the left abdominal side. (3) Treatment groups: these groups underwent the same surgical procedure as the control group to induce adhesions. Animals in these groups received linalool orally with doses of 50 and 100 mg/kg, respectively, for a period of 14 days. Moreover, rats in the sham and control groups received normal saline via gavage for 14 days. The evaluation of TNF-α, TGF-β, VEGF, and caspase 3 was performed using western blot and IHC methods. Furthermore, oxidative stress biomarkers such as MDA, TAC, GSH, and NO were assessed in the peritoneal adhesion tissue. The findings revealed that linalool significantly reduced peritoneal adhesions by reducing TNF-α, TGF-β, VEGF, and caspase 3 levels. Moreover, MDA concentration was significantly decreased, while NO, TAC, and GSH levels were notably increased. Overall, linalool was effective in preventing adhesion formation and reduced inflammation, angiogenesis, apoptosis, and oxidative stress. Therefore, linalool as a potent antioxidant is suggested for reducing postoperative adhesions in rats.

Intra-peritoneal lavage of Zingiber officinale rhizome and its active constituent gingerol impede inflammation, angiogenesis, and fibrosis following post-operative peritoneal adhesion in male rats

Post-operative peritoneal adhesions (PA) are a common and important clinical problem. In this study, we focused on the ameliorative efficacy of ginger and gingerol compounds on surgical-induced peritoneal adhesion, and their strategies that disrupted the PA formation pathways to suppress their incidence. First, liquid chromatography-mass spectrometry (LC-MS) was established to separate and identify several chemical groups of ginger rhizome extract. In the next steps, male Wistar albino rats were randomly selected and divided into various groups, namely sham, control, ginger extract (0.6, 1.8, 5 %w/v), and gingerol (0.05, 0.1, 0.3, and 1 %w/v). Finally, we investigated the macroscopic parameters such as wound healing, body weight as well as spleen height and weight. In addition, visual peritoneal adhesion assessment was performed via Nair et al and Adhesion Scoring Scheme. Moreover, the microscopic parameters and biological assessment was performed via and immunoassays. The present findings revealed significant improvement in wound healing and reduction of the adhesion range, as Nair et al. and Adhesion Scoring Scheme scoring, in both the ginger and gingerol groups compared to the PA group (P < 0.05). Whereas, gingerol (0.3 % w/v) was able to increase the body weight in rats (P < 0.0001) at end stage of experiment. Also, inflammation, angiogenesis, and fibrosis were significantly decreased due to the downregulation of interleukin (IL)-6, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1, vascular endothelial growth factor (VEGF), respectively, in the ginger and gingerol groups compared to the PA group (P < 0.05). In contrast, the levels of IL-10 were increased in the ginger and gingerol groups compared to the control group (P < 0.01). Our results proved that ginger rhizome and gingerol, as novel therapeutic compounds, could be used to prevent PA for their beneficial anti-inflammatory as well as anti-fibrosis properties in clinical trials. However, further clinical studies are required to approve the effectiveness of ginger and gingerol.

Comparison of the effect of Everolimus, Prednisolone, and a combination of both on experimentally induced peritoneal adhesions in rats

Postoperative intra-abdominal adhesions represent a significant post-surgical problem. Its complications can cause a considerable clinical and cost burden. Herein, our study aimed to investigate the effect of Everolimus on peritoneal adhesion formation after inducing adhesions in rats. In this experimental study, adhesion bands were induced by intraperitoneal injection of 3 ml of 10% sterile talc solution in 64 male albino rats. The first group served as the control group. The second one received oral Prednisolone (1 mg/kg/day), the third received Everolimus (0.1 mg/kg/day), and group four received both drugs with similar dosages for four consecutive weeks. The formation of adhesion bands was qualitatively graded according to the Nair classification. The rats in the control group had extensive adhesions between the abdominal wall and the organs. Regarding substantial adhesion formation, 50% (8/16) of animals in the control group had substantial adhesions, while this rate in the groups receiving Prednisolone, Everolimus, and combination treatment was 31%, 31%, and 31%, respectively. Also, 68.75% (5/11) of the Prednisolone recipients had insubstantial adhesions, the same as Everolimus recipients, while in the combination group, 66.66% (10/15) rats had insubstantial adhesions. Everolimus demonstrated satisfactory results in reducing the rates of induced peritoneal adhesion in an experimental model, similar to Prednisolone and superior to a combination regime.

Comparison of the preventive effect of colchicine versus diphenhydramine, prednisolone, and a combination therapy on intraperitoneal adhesion bands: an experimental study in rats

BACKGROUND

Peritoneal adhesion formation is an inevitable consequence of abnormal repair of the peritoneum following different peritoneal injuries of intra-abdominal operations with the subsequent morbidity that they represent. Vast efforts have been made to elucidate the cause and prevent the development of abdominal adhesions. The aim of our study is to compare the capability of colchicine versus diphenhydramine (DPH) and methylprednisolone (MP), and also prednisolone in adhesion prevention.

METHODS

Sixty-one male Wistar stock rats were divided into four groups. The first group attended as the control group. Groups 2, 3, and 4 received oral combination of MP + DPH solution (20 mg/kg), colchicine (0.02 mg/kg), and prednisolone (1 mg/ kg), respectively. Adhesion bands were induced by standardized abrasion of the peritoneum through a midline laparotomy. All rats were sacrificed on the 15^th-day post medication administration and the subjects underwent an exploratory laparotomy. The presence of adhesions was evaluated with the modified using Nair's classification.

RESULTS

The proportion of the control group with substantial adhesion bands (73.3%) was significantly higher than that of the MP + DPH (13.3%), colchicine (33.3%), and prednisolone (31.3%) groups. There were significant differences between the scores of the control and the MP + DPH, colchicine, and prednisolone groups (P = 0.001, 0.028, and 0.019, respectively). There was no statistically significant difference to favor colchicine against MP + DPH (P = 0.390) or MP + DPH against prednisolone (P = 0.394).

CONCLUSIONS

Both colchicine and combination of DPH + MP prevented postoperative abdominal adhesions separately in our study. However, the lowest adhesion formation rate was observed in the DPH + MP group, even lower than the prednisolone group.

Promising results of captopril in improving knee arthrofibrosis and cartilage status: an animal model study

PURPOSE

Several cytokines and growth factors start and progress the destruction process of joint hyaline cartilage and fibrosis formation. Captopril is classified as an Angiotensin-converting enzyme inhibitor in which several studies revealed that captopril significantly decreases fibrosis formation in some organs like the liver, heart, and kidney. This study aimed to evaluate the use of captopril in reducing the possibility of arthrofibrosis and osteoarthritis in an animal model.

METHOD

In this in-vivo animal model study, the anterior cruciate ligament of 24 rabbits was transected to induce osteoarthritis and arthrofibrosis. The control group contained 11 rabbits and the second group consisted of 13 rabbits. The second group was treated with 10 mg/ kilogram/day captopril through a nasogastric tube. The control group was treated with normal saline in the same way. Cartilage damage and osteoarthritis were evaluated by Osteoarthritis Research Society International (OARSI) scoring system. After 30 days, animals were sacrificed, and arthrofibrosis and cartilage damage were evaluated microscopically and macroscopically.

RESULTS

According to macroscopic and microscopic evaluation, captopril dramatically reduced arthrofibrosis formation based on visual scoring and the Masson trichrome staining system. Cartilage damage was lower in the intervention group compared to the control group.

CONCLUSIONS

Captopril is an angiotensin-converting enzyme inhibitor that demonstrated to significantly decreases the possibility of arthrofibrosis. Although the beneficial preventive effect of captopril on osteoarthritis was not proved statistically, better results may be obtained if the route of administration or drug dosage is changed.