Effects of Cholerella sp. microalgae extract on colonic anastomosis in rats with protein-energy malnutrition

Experimental models of high-risk bowel anastomosis in rats: A systematic review

BACKGROUND

Anastomotic leaks remain one of the most dreaded complications in gastrointestinal surgery causing significant morbidity, that negatively affect the patients' quality of life. Experimental studies play an important role in understanding the pathophysiological background of anastomotic healing and there are still many fields that require further investigation. Knowledge drawn from these studies can lead to interventions or techniques that can reduce the risk of anastomotic leak in patients with high-risk features. Despite the advances in experimental protocols and techniques, designing a high-quality study is still challenging for the investigators as there is a plethora of different models used.

AIM

To review current state of the art for experimental protocols in high-risk anastomosis in rats.

METHODS

This systematic review was performed according to The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. To identify eligible studies, a comprehensive literature search was performed in the electronic databases PubMed (MEDLINE) and Scopus, covering the period from conception until 18 October 2023.

RESULTS

From our search strategy 102 studies were included and were categorized based on the mechanism used to create a high-risk anastomosis. Methods of assessing anastomotic healing were extracted and were individually appraised.

CONCLUSION

Anastomotic healing studies have evolved over the last decades, but the findings are yet to be translated into human studies. There is a need for high-quality, well-designed studies that will help to the better understanding of the pathophysiology of anastomotic healing and the effects of various interventions.

Benefits of Preventive Administration of Chlorella sp. on Visceral Pain and Cystitis Induced by a Single Administration of Cyclophosphamide in Female Wistar Rat

Chlorella sp. is a green microalgae containing nutrients, vitamins, minerals, and chlorophyll. In some communities, Chlorella sp. is a traditional medicinal plant used for the management of inflammation-related diseases. In a rat model, ROQUETTE Chlorella sp. (RCs) benefits were investigated on visceral pain and associated inflammatory parameters related to cystitis both induced by cyclophosphamide (CYP). RCs was orally administered every day from day 1-16 (250 and 500 mg/kg body weight). Six hours after an intraperitoneal injection of 200 mg/kg body weight of CYP, body temperature, general behavior, food intake, and body weight were recorded. Twenty-four hours after CYP injection, rats were tested in two behavioral tests, an open field and the aversive light stimulus avoidance conditioning test, to evaluate the influence of pain on general activity and learning ability of rats. After euthanasia, bladders were weighed, their thickness was scored, and the urinary hemoglobin was measured. RCs orally administered at the two dosages significantly reduced visceral pain and associated inflammatory parameters related to cystitis both induced by CYP injection, and improved rat behavior. To conclude, RCs demonstrated beneficial effects against visceral pain and cystitis.

Administration of Chlorella sp. microalgae reduces endotoxemia, intestinal oxidative stress and bacterial translocation in experimental biliary obstruction

RATIONALE

Endotoxemia has long been documented in obstructive jaundice, and altered intestinal barrier function is considered to be one of the important mechanisms for this phenomenon. The aim of this study was to investigate the role of different microalgae (Chlorella sp. and Spirulina sp.) extracts in intestinal barrier function and oxidative stress in experimentally jaundiced rats.

METHODS

A total of 60 male wistar rats were randomly divided into four groups of 15 each: I, sham operated; II, bile duct ligation (BDL); III, BDL+Chlorella sp.; IV, BDL+Spirulina sp. Rats were fed rat chow or microalgae extracts supplemented enteral diet ten days after sham operation or BDL. Main outcome measures were endotoxin concentrations in plasma, evidence of bacterial translocation (BT) in mesenteric lymph nodes (MLNs) and liver, oxidative stress, and histology.

RESULTS

Compared to the group I, a significant increase in contamined MLNs, liver, and spleen samples and increased endotoxemia were noted in group II (P<0.01) but were significant reduced in group III (P<0.05). There was no significant difference in BT rate between the group II and group IV (P>0.05). Moreover, Chlorella sp. administration protected in jaundiced rats against oxidative stress, as demonstrated by reduction of intestinal lipid peroxidation, increase of the antioxidant reduced glutathione (GSH), and decrease of the oxidized glutathione (GSSG). The intestinal mucosa in control rats was atrophic with significantly decreased villous density and total mucosal thickness. Chlorella sp. caused a significant reduction in villous atrophy compared with controls.

CONCLUSIONS

Chlorella sp. microalgae supplemented enteral diet has significant protective effects on intestinal mucosa barrier in obstructive jaundice, and reduces intestinal translocation of bacteria and endotoxin.

Effects of microalgae chlorella species crude extracts on intestinal adaptation in experimental short bowel syndrome

AIM: To evaluate the effects of chlorella crude extract (CCE) on intestinal adaptation in rats subjected to short bowel syndrome (SBS).

METHODS: Wistar rats weighing 230-260 g were used in the study. After anesthesia a 75% small bowel resection was performed. Rats were randomized and divided into groups. Control group (n = 10): where 5% dextrose was given through a gastrostomy tube, Enteral nutrition (EN) group (n = 10): Isocaloric and isonitrogen EN (Alitraq, Abbott, USA), study group (n = 10): CCE was administrated through a gastrostomy tube. Rats were sacrificed on the fifteenth postoperative day and blood and tissue samples were taken. Histopathologic evaluation, intestinal mucosal protein and DNA levels, intestinal proliferation and apoptosis were determined in intestinal tissues, and total protein, albumin and citrulline levels in blood were studied.

RESULTS: In rats receiving CCE, villus lengthening, crypt depth, mucosal DNA and protein levels, intestinal proliferation, and serum citrulline, protein and albumin levels were found to be significantly higher than those in control group. Apoptosis in CCE treated rats was significantly reduced when compared to EN group rats.

CONCLUSION: CCE has beneficial effects on intestinal adaptation in experimental SBS.