MicroRNA-142 Critically Regulates Group 2 Innate Lymphoid Cell Homeostasis and Function.

Innate lymphoid cells are central to the regulation of immunity at mucosal barrier sites, with group 2 innate lymphoid cells (ILC2s) being particularly important in type 2 immunity. In this study, we demonstrate that microRNA(miR)-142 plays a critical, cell-intrinsic role in the homeostasis and function of ILC2s. Mice deficient for miR-142 expression demonstrate an ILC2 progenitor-biased development in the bone marrow, and along with peripheral ILC2s at mucosal sites, these cells display a greatly altered phenotype based on surface marker expression. ILC2 proliferative and effector functions are severely dysfunctional following Nippostrongylus brasiliensis infection, revealing a critical role for miR-142 isoforms in ILC2-mediated immune responses. Mechanistically, Socs1 and Gfi1 expression are regulated by miR-142 isoforms in ILC2s, impacting ILC2 phenotypes as well as the proliferative and effector capacity of these cells. The identification of these novel pathways opens potential new avenues to modulate ILC2-dependent immune functions.

Applications of Antioxidant Secondary Metabolites of Sargassum spp.

Sargassum is one of the largest and most diverse genus of brown seaweeds, comprising of around 400 taxonomically accepted species. Many species of this genus have long been a part of human culture with applications as food, feed, and remedies in folk medicine. Apart from their high nutritional value, these seaweeds are also a well-known reservoir of natural antioxidant compounds of great interest, including polyphenols, carotenoids, meroterpenoids, phytosterols, and several others. Such compounds provide a valuable contribution to innovation that can translate, for instance, into the development of new ingredients for preventing product deterioration, particularly in food products, cosmetics or biostimulants to boost crops production and tolerance to abiotic stress. This manuscript revises the chemical composition of Sargassum seaweeds, highlighting their antioxidant secondary metabolites, their mechanism of action, and multiple applications in fields, including agriculture, food, and health.

Treg sensitivity to FasL and relative IL-2 deprivation drive idiopathic aplastic anemia immune dysfunction.

Idiopathic aplastic anemia (AA) has 2 key characteristics: an autoimmune response against hematopoietic stem/progenitor cells and regulatory T-cells (Tregs) deficiency. We have previously demonstrated reduction in a specific subpopulation of Treg in AA, which predicts response to immunosuppression. The aims of the present study were to define mechanisms of Treg subpopulation imbalance and identify potential for therapeutic intervention. We have identified 2 mechanisms that lead to skewed Treg composition in AA: first, FasL-mediated apoptosis on ligand interaction; and, second, relative interleukin-2 (IL-2) deprivation. We have shown that IL-2 augmentation can overcome these mechanisms. Interestingly, when high concentrations of IL-2 were used for in vitro Treg expansion cultures, AA Tregs were able to expand. The expanded populations expressed a high level of p-BCL-2, which makes them resistant to apoptosis. Using a xenograft mouse model, the function and stability of expanded AA Tregs were tested. We have shown that these Tregs were able to suppress the macroscopic clinical features and tissue manifestations of T-cell-mediated graft-versus-host disease. These Tregs maintained their suppressive properties as well as their phenotype in a highly inflammatory environment. Our findings provide an insight into the mechanisms of Treg reduction in AA. We have identified novel targets with potential for therapeutic interventions. Supplementation of ex vivo expansion cultures of Tregs with high concentrations of IL-2 or delivery of IL-2 directly to patients could improve clinical outcomes in addition to standard immunosuppressive therapy.

Immediate versus early loading protocols of titanium-zirconium narrow-diameter implants for mandibular overdentures in edentulous patients: 1-year results from a randomized controlled trial.

OBJECTIVES: The purpose of this randomized clinical trial was to compare immediate and early loading protocols for mandibular overdentures with two-splinted narrow-diameter implants in thin, non-augmented residual ridge situations. MATERIAL AND METHODS: Each edentulous patient received two implants in the interforaminal region. If primary stability after implant placement was achieved, patients were randomized either to the immediate (48 hr post-surgery) or the early (2 weeks after surgery) loading group. In prosthetic rehabilitation, a bar prosthetic system with a titanium bar was used. Implant survival, success rates, and radiographic changes at the crestal bone level were evaluated after 1 year, and patient satisfaction was recorded at 1 and 6 months post-surgery. RESULTS: Twenty-four patients with a mean age of 67 ± 9 years were included. One patient passed away after 11 months due to treatment-independent reasons. In the 24 implants of the immediate loading group, the mean bone level change from surgery/loading to the first-year evaluation was 0.32 ± 0.80 mm (p = .066). Regarding the early group (22 implants), the mean bone level change from loading to 1 year was 0.34 ± 0.69 mm (p = .048). After 1 year, no differences could be detected between groups (p = .91) with a mean difference of 0.02 mm (95% CI: [-0.42, 0.47]). The mean implant survival and success rates were 100% for both groups. Patient satisfaction was high; however, at 6 months, there was a difference between groups regarding the ability to chew. CONCLUSIONS: Both loading protocols for mandibular overdentures supported by two-splinted narrow-diameter implants were successful at the 1-year follow-up.

Deconstructing breast cancer cell biology and the mechanisms of multidrug resistance.

Cancer complexity constantly challenges the way that clinicians manage breast cancer therapy. Tumor heterogeneity and intratumoral stroma characteristics allow cells with different phenotypes and deregulated apoptotic, proliferative and migration abilities to co-exist contributing to a disappointing therapeutic response. While new approaches are being associated with conventional chemotherapy, such as hormonal therapy or target monoclonal antibodies, recurrence and metastasization are still observed. Membrane transporters are the cell's first line of contact with anticancer drugs having a major role in multidrug resistance events. This structural-based activity enables the cell to be drug-resistant by decreasing drug intracellular concentration through an efflux-transport mechanism, mainly associated with overexpression of ATP-binding cassette (ABC) proteins. This review focuses on some of the important structural and biological properties of the malignant cell and tumor microenvironment, addressing the role of the membrane ABC transporters in therapeutic outcomes, and highlighting related molecular pathways that may represent meaningful target therapies.

Case report: Introduction of an Ahmed valve implant tube into the ciliary sulcus using a guide-wire.

BACKGROUND: Glaucoma is a progressive optic neuropathy and it is the main cause of irreversible blindness worldwide. Intraocular pressure (IOP) is the only modifiable one and trabeculectomy is commonly considered the surgical "gold standard" to decrease IOP. In particular cases, other kind of surgeries, as the Ahmed Glaucoma Valve (AGV) implant, are a reliable alternative. Usually, the silicone tube of AGV surgery is inserted into the anterior chamber. Sometimes it is necessary to place the AGV silicone tube in the ciliary sulcus, especially in cases of endothelial decompensation. This surgical procedure is not always easy to perform. CASE PRESENTATION: This article describes and presents a technique for inserting the AGV tube into the posterior chamber using a guide-wire, in a total of 12 cases are reported. This procedure has been mostly applied in a group of pseudophakic patients who need AGV placement to control elevated IOP. In exceptional situations, this procedure was applied in pseudophakic patients previously with AGV tube implanted in the anterior chamber and with loss of endothelial cells or in phakic patients with previously implanted AGV anterior chamber tube, simultaneously to cataract surgery. CONCLUSION: The purpose of these cases presentations attended at our service is to demonstrate the passage of the AGV silicone tube was performed with the aid of a guide wire.

Scheimpflug-Based Corneal Biomechanical Analysis As A Predictor of Glaucoma in Eyes With High Myopia.

Purpose: To address if corneal biomechanical behavior has a predictive value for the presence of glaucomatous optical neuropathy in eyes with high myopia. Patients and Methods: This observational cross-sectional study included 209 eyes from 108 consecutive patients, divided into four groups: high myopia and primary open-angle glaucoma (POAG) - HMG, n = 53; high myopia without POAG - HMNG, n = 53; non-myopic with POAG - POAG, n = 50; non-myopic and non-POAG- NMNG, n = 53. Biomechanical assessment was made through a Scheimpflug-camera-based technology. Receiver operating characteristic curves were made for the discrimination between groups. Multivariable logistic regression models were performed to address the predictive value of corneal biomechanics for the presence of glaucoma. Results: Areas Under the Receiver Operating Characteristic (AUROCs) above 0.6 were found in 6 parameters applied to discriminate between HMG and HMNG and six parameters to discriminate between POAG and NMNG. The biomechanical models with the highest power of prediction for the presence of glaucoma included 5 parameters with an AUROC of 0.947 for eyes with high myopia and 6 parameters with an AUROC of 0.857 for non-myopic eyes. In the final model, including all eyes, and adjusted for the presence of high myopia, the highest power of prediction for the presence of glaucoma was achieved including eight biomechanical parameters, with an AUROC of 0.917. Conclusion: Corneal biomechanics demonstrated differences in eyes with glaucoma and mainly in myopic eyes. A biomechanical model based on multivariable logistic regression analysis and adjusted for high myopia was built, with an overall probability of 91.7% for the correct prediction of glaucomatous damage.

Organizing Pneumonia and Ulcerative Colitis: A Relationship To Remember.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterised by relapsing and remitting mucosal inflammation of the colon. Despite primarily affecting the gastrointestinal tract, UC has various extraintestinal manifestations that often affect other organs and systems. Although pulmonary involvement is uncommon, organising pneumonia (OP), which affects the lung parenchyma, is one of the potential extraintestinal manifestations of UC. We report a case of OP in a 35-year-old male with a longstanding history of UC, well-medicated with sulfasalazine (SSZ). He presented to the emergency department (ED) with complaints of fatigue, coughing, myalgia, thoracalgia and dyspnoea. A chest X-ray showed parenchymal infiltrates and computed tomography revealed bilateral consolidation. Under a preliminary diagnosis of atypical pneumonia, he was treated with an empirical broad-spectrum antimicrobial agent, which did not lead to any clinical, laboratory or imaging improvement. Furthermore, the diagnostic work-up excluded any malignancy or infectious cause. A probable diagnostic hypothesis was OP as an extraintestinal manifestation of UC or as an adverse effect of SSZ therapy. Hence, SSZ was discontinued, and he was successfully treated with corticosteroids, exhibiting significant improvements and recovering completely during the follow-up period. Despite lung involvement in UC being rare, we present this case to emphasise the importance of a thorough differential diagnosis when treating acute respiratory illness in patients with UC, including extraintestinal manifestations of UC, especially OP, even during a period of remission. We also emphasise the importance of early initiation of corticosteroid therapy to prevent major complications and promote recovery.

Modified Technique of Ex-PRESS® Filtration Device Combined with a Scleral Pocket for Hereditary Transthyretin Amyloidosis (hATTR) Secondary Open-Angle Glaucoma.

Purpose: To evaluate the effectiveness and safety of a modified approach using the Ex-PRESS® implant combined with a scleral pocket in the management of secondary open-angle glaucoma in hereditary transthyretin amyloidosis (hATTR) at our department. Methods: This was a retrospective analysis. The primary endpoints included Intraocular pressure (IOP) evaluation (baseline, 1st day, 1st week, 1, 3, 6, 12 months and at last follow-up) and number of hypotensive drugs (baseline, 6th, 12th months and at last follow-up). As secondary endpoints surgical complications, the need for additional glaucoma surgery and LogMAR BCVA were evaluated. Qualified and complete success were defined as ≥ 30% IOP decrease from baseline, with or without additional medications, respectively. The minimum follow-up was 12 months. Results: A total of 32 eyes were included with a mean follow-up of 2.4±2.9 years. IOP decreased significantly from baseline (27.4±4.4 mmHg) to 1st day (5.00±2.9 mmHg), 1st week (6.9±4.1 mmHg), 1st month (11.7±7.8 mmHg), 3rd month (11.6±6.1 mmHg), 6th month (13.1±6.8 mmHg), 12th month (12.0±3.5 mmHg) and last visit (11.8±2.4 mmHg), p<0.001. There was also a significant reduction in the number of antiglaucoma medications from baseline (3.8±0.6) and last follow-up (0.4±0.8), p<0.001. LogMAR BCVA remained stable (0.25±0.26 at baseline and 0.25±0.24 at last follow-up), p=0.767. Transient hypotony occurred in 17 eyes (53.1%), but only 11 (34.4%) exhibited anterior chamber shallowing and needed additional care, namely cycloplegic drops and viscoelastic injection. Complete surgical success was achieved in 22 eyes (68.8%) and qualified success in 6 eyes (18.8%). Four eyes (12.5%) needed additional glaucoma surgery. Conclusion: The modified ExPRESS® technique appears to be effective, especially when low levels of IOP are required. Additionally, fewer anti-glaucoma drugs were necessary. In the other hand, hypotony was a common side effect with this procedure, although all patients were properly handled, preserving the surgical outcomes.

Antitumor Effects of Cannabis sativa Bioactive Compounds on Colorectal Carcinogenesis.

Cannabis sativa is a multipurpose plant that has been used in medicine for centuries. Recently, considerable research has focused on the bioactive compounds of this plant, particularly cannabinoids and terpenes. Among other properties, these compounds exhibit antitumor effects in several cancer types, including colorectal cancer (CRC). Cannabinoids show positive effects in the treatment of CRC by inducing apoptosis, proliferation, metastasis, inflammation, angiogenesis, oxidative stress, and autophagy. Terpenes, such as ß-caryophyllene, limonene, and myrcene, have also been reported to have potential antitumor effects on CRC through the induction of apoptosis, the inhibition of cell proliferation, and angiogenesis. In addition, synergy effects between cannabinoids and terpenes are believed to be important factors in the treatment of CRC. This review focuses on the current knowledge about the potential of cannabinoids and terpenoids from C. sativa to serve as bioactive agents for the treatment of CRC while evidencing the need for further research to fully elucidate the mechanisms of action and the safety of these compounds.

Phytates as a natural source for health promotion: A critical evaluation of clinical trials.

Phytates are a type of organophosphorus compound produced in terrestrial ecosystems by plants. In plant feeds, phytic acid and its salt form, phytate, account for 60%-80% of total phosphorus. Because phytate is a polyanionic molecule, it can chelate positively charged cations such as calcium, iron, and zinc. Due to its prevalence in vegetal tissues and the fact that people consume plants, phytate was first considered a potential health benefit. This updated review aims to summarize the current data on the results of clinical trials of phytates on human health, highlighting both beneficial and undesirable effects. To obtain these updated data, published papers in electronic databases such as PubMed/MedLine, TRIP database, Wiley, Google Scholar, Baidu, and Scopus were searched. Study results have shown that phytate can have beneficial health effects such as antioxidant, anticancer potential and reduction of pathological calcifications in blood vessels and organs; but also, negative effects by reducing the absorption of minerals important for maintaining the homeostasis of the human body. According to these recent results derived from recent clinical studies, phytates may be a potential natural source for health benefits. To improve clinical efficacy and human health benefits, further dose-response studies are needed to determine effective therapeutic doses and potential interactions with conventional drugs.

The Impact of Resveratrol-Enriched Bread on Cardiac Remodeling in a Preclinical Model of Diabetes.

The World Health Organization aims to stop the rise of diabetes by 2025, and diet is one of the most efficient non-pharmacological strategies used to prevent it. Resveratrol (RSV) is a natural compound with anti-diabetic properties, and incorporating it into bread is a suitable way to make it more accessible to consumers as it can be included as part of their daily diet. This study aimed to evaluate the effect of RSV-enriched bread in preventing early type 2 diabetes cardiomyopathy in vivo. Male Sprague Dawley rats (3 weeks old) were divided into four groups: controls with plain bread (CB) and RSV bread (CBR), and diabetics with plain bread (DB) and RSV bread (DBR). Type 2 diabetes was induced by adding fructose to the drinking water for two weeks followed by an injection of streptozotocin (STZ) (40 mg/kg). Then, plain bread and RSV bread (10 mg RSV/kg body weight) were included in the rats' diet for four weeks. Cardiac function, anthropometric, and systemic biochemical parameters were monitored, as well as the histology of the heart and molecular markers of regeneration, metabolism, and oxidative stress. Data showed that an RSV bread diet decreased the polydipsia and body weight loss observed in the early stages of the disease. At the cardiac level, an RSV bread diet diminished fibrosis but did not counteract the dysfunction and metabolic changes seen in fructose-fed STZ-injected rats.

Studying and Analyzing Humane Endpoints in the Fructose-Fed and Streptozotocin-Injected Rat Model of Diabetes.

This work aimed to define a humane endpoint scoring system able to objectively identify signs of animal suffering in a rat model of type 2 diabetes. Sprague-Dawley male rats were divided into control and induced group. The induced animals drink a 10% fructose solution for 14 days. Then, received an administration of streptozotocin (40 mg/kg). Animals' body weight, water and food consumption were recorded weekly. To evaluate animal welfare, a score sheet with 14 parameters was employed. Blood glucose levels were measured at three time points. After seven weeks of initiating the protocol, the rats were euthanized. The induced animals showed weight loss, polyuria, polyphagia, and polydipsia. According to our humane endpoints table, changes in animal welfare became noticeable after the STZ administration. None of the animals hit the critical score limit (four). Data showed that the most effective parameters to assess welfare in this type 2 diabetes rat induction model were dehydration, grooming, posture, abdominal visualization, and stool appearance. The glycemia was significantly higher in the induced group when compared to the controls (p < 0.01). Induced animals' murinometric and nutritional parameters were significantly lower than the controls (p < 0.01). Our findings suggest that in this rat model of type 2 diabetes with STZ-induced following fructose consumption, our list of humane endpoints is suitable for monitoring the animals' welfare.

Ahmed valve for secondary glaucoma in patients with hereditary transthyretin amyloidosis.

OBJECTIVE: To evaluate the surgical outcomes of patients with hereditary transthyretin amyloidosis (TTR-FAP) who underwent Ahmed glaucoma valve (AGV) implantation. METHODS: A retrospective cohort study was performed on patients with a diagnosis of TTR-FAP secondary glaucoma, who underwent AGV implantation in our department, between November 2010 and July 2019. The cumulative probability of treatment success was measured with Kaplan-Meier survival analysis. The primary outcome was success, defined as intraocular pressure (IOP) ≥ 6 mmHg and ≤21 mmHg with or without medication, with no need for further glaucoma surgery and without loss of light perception at last follow-up. Secondary outcomes were postoperative IOP, number of IOP-lowering medications, and rates of complications. RESULTS: The study included 114 eyes of 87 patients. The mean follow-up duration was 3.81 ± 2.11 years (y) [range, 1.00-8.28 y]. Compared to the preoperative values, the mean IOP was reduced from 28.20 ± 7.01 to 12.87 ± 3.76 mmHg at the final visit (p < 0.001), with a reduction in the number of medications from 3.89 ± 0.66 to 1.86 ± 1.43 (p < 0.001). Early and late postoperative complications occurred in 20 (17.09%) and 9 (7.89%) eyes, respectively. Kaplan-Meier analysis indicated probabilities of success of 0.98 at 1 y, 0.97 at 2 y, 0.95 at 3 y, 0.89 at 4 y, 0.77 at 5 y and 0.72 at 6 y. The linear correlation analysis showed a correlation between some characteristics of the natural history of TTR-FAP patients and AGV implantation success. CONCLUSION: Although glaucoma in TTR-FAP patients is very difficult to manage, AGV implantation is an effective and relatively safe procedure.

XEN Gel Stent Implantation in Eyes With Previous Glaucoma Filtering Surgeries: A Case Series.

Background In this study, we aimed to analyze the efficacy and safety of ab interno XEN® gel stent (Allergan Inc., Dublin, Ireland) implantation in a series of eyes with open-angle glaucoma and a history of previous filtering glaucoma surgeries. Methodology This retrospective, single-center study included all eyes that underwent XEN gel implantation with a minimum follow-up of 18 months that had previously undergone a filtering glaucoma surgery. The main outcomes were intraocular pressure (IOP) variation (baseline, first day, first week, and first, third, sixth, 12th, and 18th months), the number of hypotensive eyedrops at 18 months, intraoperative and postsurgical complications, and the need for subsequent glaucoma surgery. Results A total of 10 eyes from nine patients were enrolled in the study. IOP significantly decreased from 24.0 ± 2.4 mmHg to 7.8 ± 1.6 mmHg on the first day, 9.4 ± 2.2 mmHg in the first week, and 12.3 ± 4.8 mmHg, 14.7 ± 4.3 mmHg, 13.3 ± 3.8 mmHg, 11.7 ± 1.9 mmHg, and 12.3 ± 1.9 at the first, third, sixth, 12th, and 18th month, respectively (p < 0.001), with a 49.5% reduction in IOP at the end of the follow-up. The number of hypotensive eyedrops decreased significantly from 3.5 ± 0.5 (3-4) to 0.7 ± 0.7 (0-2) (p = 0.026). No intraoperative or postsurgical complications were recorded. In total, seven (70%) eyes achieved controlled IOP of <18 mmHg without any anti-glaucomatous medications, and one (10%) eye with the use of topical prostaglandin. One (10%) eye was submitted to a surgical revision, and another needed an additional glaucoma surgery during follow-up, with appropriate IOP control at the last follow-up. Conclusions This case series aims to highlight that the XEN implant can be an option in eyes with IOP levels in the low 20s and previously failed filtering surgeries, with satisfactory efficacy and high safety.

Corneal Biomechanics for Ocular Hypertension, Primary Open-Angle Glaucoma, and Amyloidotic Glaucoma: A Comparative Study by Corvis ST.

BACKGROUND: To evaluate biomechanical parameters of the cornea provided by Corvis ST in patients with ocular hypertension, primary open-angle glaucoma, and amyloidotic glaucoma and to compare with healthy controls. METHODS: This was a cross-sectional study of patients with ocular hypertension, primary open-angle glaucoma, and amyloidotic glaucoma that underwent Corvis ST imaging. Primary outcome was the comparison of corneal biomechanical parameters between study groups after adjusting for age, gender, Goldmann intraocular pressure (GAT-IOP), and prostaglandin analogues medication. Secondary outcome was the comparison of different IOP measurements in each group. RESULTS: One hundred and eighty-three eyes from 115 patients were included: 61 with primary open-angle glaucoma, 32 with amyloidotic glaucoma, 37 with ocular hypertension and 53 were healthy controls. Amyloidotic glaucoma group had smaller radius (p=0.025), lower deflection amplitude at highest concavity (p=0.019), and higher integrated radius (p=0.014) than controls. Ocular hypertension group had higher stiffness parameter at first applanation (p=0.043) than those with primary open-angle glaucoma, and higher stress-strain index (p=0.049) than those with amyloidotic glaucoma. Biomechanically corrected intraocular pressure was significantly lower than Goldmann intraocular pressure in group with primary open-angle glaucoma (p=0.005) and control group (p=0.013), and Goldmann intraocular pressure adjusted for pachymetry in group with primary open-angle glaucoma (p=0.01). CONCLUSION: Eyes with amyloidotic glaucoma have more deformable corneas, while eyes with ocular hypertension have less deformable corneas. These findings may be linked to the susceptibility to glaucomatous damage and progression. There were significant differences between Goldmann applanation tonometry and biomechanically corrected intraocular ocular pressure provided by Corvis ST.

Organoids capture tissue-specific innate lymphoid cell development in mice and humans.

Organoid-based models of murine and human innate lymphoid cell precursor (ILCP) maturation are presented. First, murine intestinal and pulmonary organoids are harnessed to demonstrate that the epithelial niche is sufficient to drive tissue-specific maturation of all innate lymphoid cell (ILC) groups in parallel, without requiring subset-specific cytokine supplementation. Then, more complex human induced pluripotent stem cell (hiPSC)-based gut and lung organoid models are used to demonstrate that human epithelial cells recapitulate maturation of ILC from a stringent systemic human ILCP population, but only when the organoid-associated stromal cells are depleted. These systems offer versatile and reductionist models to dissect the impact of environmental and mucosal niche cues on ILC maturation. In the future, these could provide insight into how ILC activity and development might become dysregulated in chronic inflammatory diseases.

Dicoumarol: from chemistry to antitumor benefits.

Dicoumarol, a coumarin-like compound, is known for its anticoagulant properties associated with the ability to inhibit vitamin K, being prescribed as a drug for several decades. The pharmaceutical value of dicoumarol turned it into a focus of chemists' attention, aiming its synthesis and of dicoumarol derivatives, bringing to light new methodologies. In recent years, several other bioactive effects have been claimed for dicoumarol and its derivatives, including anti-inflammatory, antimicrobial, antifungal, and anticancer, although the mechanisms of action underlying them are mostly not disclosed and additional research is needed to unravel them. This review presents a state of the art on the chemistry of dicoumarols, and their potential anticancer characteristics, highlighting the mechanisms of action elucidated so far. In parallel, we draw attention to the lack of in vivo studies and clinical trials to assess the safety and efficacy as drugs for later application.

An Integrative Approach to Characterize the Early Phases of Dimethylhydrazine-Induced Colorectal Carcinogenesis in the Rat.

This study aimed to characterize an animal model of colorectal cancer (CRC) in the early stages of disease development. Twenty-nine male Wistar rats were divided into two control groups (CTRL1 and CTRL2), receiving EDTA-saline injections and two induced groups (CRC1 and CRC2), receiving 1,2-dimethylhydrazine (DMH) injections for seven consecutive weeks. CRC1 and CTRL1 were euthanized at the 11th week, while CRC2 and CTRL2 were euthanized at the 17th week. DMH treatment decreased microhematocrit values and IL-6, ghrelin, and myostatin serum levels. Histopathological analysis of intestinal sections showed that DMH-treated rats were characterized by moderate to severe epithelial dysplasia. An adenoma was observed in one animal (CRC2 group), and the presence of inflammatory infiltrate at the intestinal level was primarily observed in DMH-treated animals. DMH also induced Ki-67 immunoexpression. The gut microbiota analysis showed a higher abundance of Firmicutes, Clostridia, Clostridiales, Peptostreptococcaceae, Blautia, Romboutsia, and Clostridium sensu stricto in CRC than CTRL rats, whereas Prevotellaceae, Prevotella, Akkermansia, and Lactobacillus levels were more prevalent in CTRL animals. Our results suggest that this model could be helpful to investigate chemoprevention in the early stages of CRC.