Morphometric analysis of the effects of antineoplastic drugs on mucosa of normal ileum and ileal anastomoses in rats

Tocopherol Enhances the Antioxidant Defense System and Histomorphometric Parameters in The Gastrointestinal Tract of Rats Treated with Sodium Arsenite

Arsenic compromises the gastrointestinal integrity and function via the body's anti-oxidative system breakdown.  Hence, this study aimed to investigate the effects of tocopherol on redox imbalance and histoarchitectural alterations in rats' gastrointestinal tract exposed to sodium arsenite. Sodium arsenite and graded doses of tocopherol were administered orally into experimental rats assigned to different groups for four weeks concurrently. Redox status assay was done in homogenized samples by spectrophotometry. Parietal cell mass and mucous cell density (stomach), villus height and crypt depth (ileum), goblet cells count, and crypt depth (colon) were evaluated by histomorphometry. Inflammatory cells infiltration was also assessed using a semi-quantitative procedure. Sodium arsenite caused a significant increase in Malondialdehyde and Myeloperoxidase but, decreased Superoxide dismutase, Catalase, Nitric oxide, Glutathione peroxidase, Glutathione, and Glutathione-S-Transferase. Tocopherol treatment reversed the changes (p<0.05) though not largely dose-dependent. Furthermore, tocopherol annulled sodium arsenite-induced increase in parietal cell mass and decrease in mucous cell density in the stomach, decrease in villus height and villus height/crypt depth ratio in the ileum, and decrease in goblets cells and increase in crypt depth in the colon. Moreover, activated inflammatory cell infiltration by sodium arsenite was mitigated by tocopherol. Sodium arsenite provokes not only marked inflammatory cellular infiltration but a focal loss of glands, hyperplasia of crypts, atrophic villi, and hypertrophy of Peyer's patches in the intestines, which are all lessened with tocopherol treatment.  These findings underscore the anti-oxidative properties of tocopherol as a potent dietary factor against sodium arsenite toxicity in the gastrointestinal tract. Keywords: Tocopherol, arsenic, stomach, ileum, colon.

The Effects of a Phytogenic Additive on the Histomorphometric Characteristics of the Intestines in Weaned Pigs with a Subclinical Natural Infection with Lawsonia intracellularis

Proliferative enteropathy, also known as proliferative ileitis, is considered to be one of the most economically important diseases in pig production worldwide. The estimated losses per affected growing pig usually range from US $1 to $5. The disease is caused by Lawsonia intracellularis, a Gram-negative, obligately intracellular bacterium. Control of the disease can be achieved with the use of vaccines or antibiotics. Recently there has been an increase in the efforts in the control of certain pathologies of the digestive system with phytogenic additives. The aim of this work was to assess the effects of a phytogenic additive on the histomorphometric characteristics of the intestines in weaned pigs with a subclinical infection with L. intracellularis acquired spontaneously. Histomorphometry analysis showed that crypt depth was significantly shorter (P<0.05), and the villus-height-to-crypt-depth ratio (P<0.05) significantly greater in the treatment group than the control. This improvement in the histological parameters of the intestine, considered to be indicators of its health, proved the positive effect of the tested additive on the digestive system in pigs.

Assessment of dose-response relationship of 5-fluorouracil to murine intestinal injury

5-Fluorouracil (5-FU) is the most frequently prescribed anti-tumor drug, but has been reported to result in intestinal injury. Although some progress has been made in understanding the intestinal toxicity of 5-FU, confusion remains about animal models of 5-FU-induced intestinal injury, especially the dosage of 5-FU. This study aims to assess the dose-response relationship between the severity of intestinal injury and different doses of 5-FU, and to determine a proper dosing for the murine model. We found that mice in the 5-FU groups gradually lost body weight over time. Increasing doses of 5-FU resulted in more severe diarrhea, with a concomitant increase in mortality. Histopathological damage was more severe in mice that received higher doses of 5-FU. In addition, plasma diamine oxidase (DAO) activity decreased in experimental mice with intestinal injury in a dose-dependent way. TUNEL and western blot analysis showed cell apoptosis in the ileum and colon related to 5-FU dosage. However, administration of 200 and 400 mg/kg 5-FU caused extremely high mortality, severe diarrhea and histopathological damage, but 25 mg/kg 5-FU did not result in significant intestinal injury. The severity of intestinal injury induced by 5-FU appeared to be dose-dependent and we concluded that the proper dosage of 5-FU to induce a murine model with intestinal mucositis ranged from 50 mg/kg to 100 mg/kg.

Exogenous glucagon-like peptide-2 (GLP-2) prevents chemotherapy-induced mucositis in rat small intestine

PURPOSE

Gastrointestinal mucositis is an unwanted and often dose-limiting side effect to most cancer treatments. Glucagon-like peptide-2 (GLP-2) is a peptide secreted from intestinal L-cells in response to nutrient intake. The peptide is involved in the regulation of apoptosis and proliferation in the intestine. We aimed to investigate the role of GLP-2 in experimental chemotherapy-induced mucositis. METHODS STUDY 1: Rats were given a single injection with 5-fluorouracil (5-FU) and killed in groups of five each day for 5 days. Blood samples were analysed for GLP-2 concentrations. The intestine was analysed for weight loss, morphometric estimates and proliferation. STUDY 2: Rats were treated with GLP-2 or control vehicle 2 days before a single injection of 5-FU or saline. The treatments continued until kill 2 days after. The intestine was investigated for influx of myeloperoxidase (MPO)-positive cells and morphometric estimates, such as villus height, as a marker of mucositis. RESULTS STUDY 1: Two days after chemotherapy, there was a rise in endogenous GLP-2, followed by a marked increase in proliferation. STUDY 2: Exogenous GLP-2 was able to protect the intestine from severe weight loss and completely prevented the reduction in villus height in the control rats. Furthermore, there was a significant decrease in influx of MPO-positive cells in the GLP-2-treated rats.

CONCLUSION

GLP-2 is secreted from the intestine in response to intestinal injury, probably explaining the compensatory hyperproliferation after chemotherapy. Exogenous GLP-2 can protect the mucosa from chemotherapy-induced mucositis in rats.

The significance of altered gastrointestinal permeability in cancer patients

PURPOSE OF REVIEW

The diagnosis and assessment of severity of intestinal mucosal damage in cancer patients treated by anticancer therapy still rely mostly on anamnestic data. We review here studies reporting on the use of intestinal permeability measurements in cancer patients before and during treatment.

RECENT FINDINGS

The concept of intestinal permeability is based on differential permeability of intestinal mucosa to molecular markers, including monosaccharides and disaccharides, along the crypt-villus axis. Cytotoxic drugs and/or radiation impair replacement of intestinal epithelia and induce flattening of the villi, leading to increased exposure of luminal contents to crypts and increased disaccharide absorption. Increased disaccharide/monosaccharide ratio and decreased xylose absorption have been described in patients treated by radiotherapy as well as different cytotoxic or targeted agents across a spectrum of malignant disorders. Intestinal permeability changes correlated with clinical manifestations, including diarrhea, mucositis, neutropenic enterocolitis and systemic infections. The measurement of intestinal permeability has also been used as a surrogate end-point in interventional studies.

SUMMARY

Intestinal permeability testing using nonmetabolized sugars may represent a tool for noninvasive objective assessment of intestinal toxicity of anticancer therapy.

Lapatinib side-effect management

Lapatinib is an oral dual tyrosine kinase inhibitor targeting epidermal growth factor receptor and HER2. Diarrhea and dermatologic adverse events are reported commonly by patients treated with lapatinib. Diarrhea can range from mild to severe based on the agents used in combination with lapatinib. The adverse events may diminish quality of life, reduce treatment adherence, and lead to discontinuation of therapy. Consequently, proactive management of diarrhea is crucial, especially in patients receiving lapatinib in combination with other agents that also cause diarrhea. As the utility of lapatinib expands, crucial proactive diarrhea-management and dose-reduction strategies are evolving to decrease the likelihood of grade 3 or 4 toxicity. With regard to dermatologic adverse events, most are mild to moderate in severity, are of limited duration, and frequently do not require treatment intervention. However, in some patients, management of dermatologic adverse events is of great importance. This article reviews data regarding diarrhea and dermatologic adverse events in patients treated with lapatinib and summarizes the key role that oncology nurses play in educating patients about the potential for adverse events and the importance of preventive measures, ongoing surveillance, appropriate treatment, and dose reductions.

Pooled analysis of diarrhea events in patients with cancer treated with lapatinib

PURPOSE

To characterize diarrhea events in patients with cancer treated with lapatinib as monotherapy or in combination with capecitabine or taxanes.

PATIENTS AND METHODS

Eleven clinical trials (phase I, II, or III) in patients with metastatic cancer were analyzed. Lapatinib was administered at doses ranging from 1,000 to 1,500 mg/day as monotherapy (n = 926) or in combination with capecitabine (n = 198) or taxanes (n = 687). Diarrhea events were characterized based on severity, time to onset, duration, required interventions, and clinical outcomes.

RESULTS

In the pooled analysis of nine studies, diarrhea occurred in 55% of lapatinib-treated patients and 24% of patients not receiving lapatinib. All grade diarrhea occurred in 51% of patients treated with lapatinib monotherapy and 65% treated with lapatinib plus capecitabine. In a separate analysis, 48% of patients treated with lapatinib plus a taxane experienced diarrhea. Overall, most diarrhea events were grade 1/2. Grade 3 events occurred in <10% of patients and grade 4 events were rare (<or=1%). Most diarrhea events resolved with conventional approaches and without dose modification. Approximately 40% of patients treated with lapatinib monotherapy or combination therapy experienced a first diarrhea event within 6 days of treatment initiation, with a median duration of 7-9 days. Lapatinib-containing chemotherapy regimens do not cause severe diarrhea when proactive monitoring and intervention is introduced.

CONCLUSION

Most diarrhea events in lapatinib-treated patients are low grade, requiring infrequent lapatinib dose modification or interruption. Proactive management of diarrhea is crucial to prevent more serious complications in lapatinib-treated patients.

Octreotide in the management of chemoradiotherapy-induced diarrhea refractory to loperamide in patients with rectal carcinoma

OBJECTIVE

To evaluate the efficacy of octreotide in the treatment of chemoradiotherapy (CRT)-induced diarrhea (CRTID) refractory to conventional loperamide treatment in this pilot study.

METHODS

Forty-two rectal carcinoma (T(3-4)N(0-2)M(0)) patients with grade 2 or 3 diarrhea refractory to loperamide were enrolled to receive octreotide. Eligible patients were treated with pelvic radiotherapy combined with bolus 5- fluorouracil CRT. Octreotide was administered subcutaneously, 150 microg three times daily, for 5 consecutive days. Only complete resolution of diarrhea was considered as therapeutic success.

RESULTS

Diarrhea mainly occurred in the first 4 weeks of CRT (83.3%) and completely resolved in 34 patients (80.9%) following octreotide administration. Mean time to response was 2.7 days: 27 patients (64%) responded during the first 3 days, and the remaining 7 (17%) on days 4 and 5. No significant side effect was reported. Eight patients (19.1%) with refractory diarrhea were hospitalized for additional treatment. No treatment delay was reported in complete responders, whereas an average 7.7-day delay was observed in refractory patients. Antidiarrheal treatment was administered on an outpatient basis in the response group, whereas refractory patients were hospitalized for an average of 8.8 days.

CONCLUSION

Daily subcutaneous octreotide administration (150 microg t.i.d.) for 5 days is apparently an effective, tolerable treatment modality for concurrent CRTID refractory to loperamide.

Intestinal toxicity induced by 5-fluorouracil in pigs: a new preclinical model

BACKGROUND

The goal of this study was to develop an animal model of intestinal injury induced by 5-fluorouracil (5-FU) in pigs.

METHODS

Six domestic pigs were used as control (healthy group) and another 6 malnourished pigs orally received 5-FU (treated group). After 4 weeks of treatment, pigs were sacrificed and jejunum, ileum and colon were isolated for histological, immunological and biochemical analyses.

RESULTS

5-FU caused a decrease in the intestinal mass. Disaccharidase, and phosphate alkaline activities, and glutathione redox cycle were disrupted by 5-FU. Histopathological alterations in the crypts and villous were greater in the small intestine than in the colon. 5-FU decreased the number of peripheral and intestinal leukocytes, promoting an increase in T-cytotoxic cells and a decrease in T-helper and B cells.

CONCLUSION

This pig model of intestinal dysfunction closely mimics the common side effects of cancer chemotherapy in humans, and provides a useful tool for evaluating novel antimucotoxic agents.

The effect of oral glutamine on 5-fluorouracil/leucovorin-induced mucositis/stomatitis assessed by intestinal permeability test

BACKGROUND & AIMS

Systemic chemotherapy may damage gastrointestinal epithelium. Mucositis is associated with increased intestinal permeability (IP). It is known that IP test with chromium 51-ethylene diaminetetra-acetate (51Cr-EDTA) is a useful tool to assess the mucositis. Oral glutamine supplements (OGS) may have a role in the prevention of chemotherapy-induced mucositis/stomatitis. The aim of this study was to characterize the relationship between the urinary excretion of 51Cr-EDTA and the severity of mucositis, and the effect of OGS on 5-fluorouracil/leucovorin (FU/LV)-induced mucositis/stomatitis.

METHODS

Fifty-one patients with advanced or metastatic cancer received FU/LV chemotherapy. The control group included 18 healthy volunteers. IP was assessed via the measurement of 51Cr-EDTA urinary excretion after oral challenge, on days 7 after the discontinuation of chemotherapy. Of the 51 patients, 22 patients received OGS (30 g/day) and 29 received only best supportive care (BSC). Glutamine supplementation continued for 15 days. It was initiated at least 3 days before the beginning of chemotherapy. Mucositis/stomatitis was graded according to version 3.0 of the Common Terminology Criteria for Adverse Events.

RESULTS

In the chemotherapy group, the median (25 percentile, 75 percentile) IP test score was significantly higher than those of the control group [6.78% (4.63, 10.66) vs. 2.17% (1.38, 2.40), P<0.001]. The severity of stomatitis was significantly correlated with IP test scores (r=0.898, P<0.001). In the OGS group, the median IP test score was significantly lower than that of the BSC group [4.69% (3.10, 6.48) vs. 8.54% (6.48, 15.31), P<0.001]. A mucositis/stomatitis of grade 2-4 was observed in two patients of the OGS group (9%), and in 11 patients (38%) in the BSC group (P<0.001).

CONCLUSIONS

The IP test may be a useful tool in the evaluation of mucositis/stomatitis. OGS may exert a protective effect on FU/LV-induced mucositis/stomatitis. Further studies, however, will be necessary to define the role of glutamine supplementation in FU/LV-induced mucositis/stomatitis.

Cancer chemotherapy-induced diarrhoea and constipation: mechanisms of damage and prevention strategies

BACKGROUND

Diarrhoea and constipation are common toxicities of chemotherapy, and both are poorly understood. They are manifestations of alimentary mucositis, a condition which affects the entire gastrointestinal tract.

DISCUSSION

The absolute percentage of patients that have diarrhoea or constipation as a result of their treatment has yet to be fully defined, although general estimates place 10% of patients with advanced cancer as being afflicted. Although there has been some major progress in recent years with understanding the mechanisms of oral and small intestinal mucositis, diarrhoea and constipation have received very little attention. Although diarrhoea is a well-recognised side-effect of both chemotherapy and radiotherapy, very little research has been conducted on the mechanisms behind diarrhoea or its treatment. Much of the information in the published literature is based on clinical observations with very little basic science existing. Constipation is not as well recognised and very little is known about its mechanisms.

OBJECTIVES

This review will examine in detail the potentially complex pathogenesis of post-chemotherapy diarrhoea in both animal models and the clinical setting. Furthermore, it will explore what is known about chemotherapy-induced constipation. It will then outline an evidence-based pathway for the investigation and treatment of post-chemotherapy diarrhoea and constipation.

Alanyl-glutamine hastens morphologic recovery from 5-fluorouracil-induced mucositis in mice

OBJECTIVE

In this study, we postulated the beneficial role of oral alanyl-glutamine, a more stable glutamine derivative to decrease 5-fluorouracil (5-FU)-induced mucositis in mice.

METHODS

We measured different morphologic parameters to assess structural changes over time in the small bowel, including crypt depth, villus height, villus area, mitotic and apoptotic indices at the crypt level using terminal deoxyuridine triphosphate nick end labeling, and hematoxylin-eosin staining of ileal tissue. In addition, we analyzed the effect of different alanyl-glutamine concentrations on animal weight curves after 5-FU treatment.

RESULTS

Neither glutamine nor alanyl- glutamine prevented the 5-FU intestinal structural damage or apoptosis in crypt enterocytes at 24 h after 5-FU challenge. However, we found that alanyl-glutamine, but not glutamine, speeds intestinal recovery when compared with 5-FU-treated controls (P < 0.05), predominantly by enhancing mitotic activity and crypt length.

CONCLUSION

Our findings provide important data to support clinical studies of oral alanyl-glutamine in 5-FU-induced mucositis.

The efficacy of octreotide in the therapy of acute radiation-induced diarrhea: a randomized controlled study

PURPOSE

Although the somatostatin analog octreotide is currently used in the treatment of chemotherapy-induced diarrhea and secretory diarrhea associated with various disorders, its role in the management of radiation enteritis is not well defined. We performed a randomized study that compared octreotide acetate with diphenoxylate hydrochloride plus atropine sulfate, the drug commonly used as therapy for acute radiation-induced diarrhea (ARID).

METHODS AND MATERIALS

Sixty-one patients with Grade 2 (four to six stools per day) or Grade 3 (> or = seven stools per day, National Cancer Institute Common Toxicity Criteria) diarrhea associated with pelvic radiotherapy were assigned randomly to receive octreotide s.c., 100 microg three times daily (n = 33) or diphenoxylate and atropine orally, 2.5 mg four times daily (n = 28). Radiotherapy was delivered to all patients in a conventional manner, with high-energy photons in a total dose > or =45 Gy, which exceeds the tolerance of intestine. Overall, there was no significant difference in patient characteristics or radiotherapy applied between the two arms. Patients were evaluated daily for the primary study end point, resolution of diarrhea, as well as for interruption of pelvic radiotherapy.

RESULTS

Within 3 days, ARID completely resolved in 20 patients in the octreotide arm (2 within the first day, 11 within the second day, and 7 within the third day) vs. only 4 (all within the second day of therapy) in the diphenoxylate arm (p = 0.002). On the diphenoxylate arm, 15/28 patients were required to discontinue pelvic radiotherapy; on the octreotide arm, 6/33 patients were required to discontinue pelvic radiotherapy for an average of 1.89 +/- 0.5 and 0.45 +/- 0.2 days, respectively (p = 0.003). No side effects were observed in either arm. Three patients on the diphenoxylate arm and only 1 on the octreotide arm required further treatment for parenteral replenishment of fluids and electrolytes or other antidiarrheal treatments.

CONCLUSION

Octreotide seems to be more effective than conventional therapy with diphenoxylate and atropine in controlling ARID and eliminating the need for radiotherapy interruptions.

Effect of chemotherapy with 5-fluorouracil on intestinal permeability and absorption in patients with advanced colorectal cancer

5-Fluorouracil (5-FU), in association with leucovorin (LV), is the most used chemotherapy agent in the treatment of colorectal cancer. Response rate, as well as side-effect incidence, increases with the dose intensity of regimens that are used. The most common dose-limiting toxicity for 5-FU/LV modulation is diarrhea. To assess the modification of small intestinal function, we investigated the changes in intestinal permeability (IP) and intestinal absorption (IA) in 41 chemo-naive patients (21 men and 22 women; mean age, 61 +/- 9 years) with advanced colorectal cancer after treatment with the association of folinic acid and 5-FU. After chemotherapy administration, we found a marked increase in IP and a reduction in IA, measured as cellobiose-mannitol (CE-MA) ratio (p < 0.0001) and D-xylose absorption (p = 0.0001), respectively. Patients who experienced diarrhea have an increase in CE-MA ratio and a reduction in D-xylose absorption values, both statistically significant. Cellobiose-mannitol ratio and D-xylose absorption tests can be used for the assessment of toxic effect of 5-FU on mature intestinal epithelium and also for evaluating the role of cytoprotective agents.

Octreotide in the treatment of severe chemotherapy-induced diarrhea

BACKGROUND

Chemotherapy-induced diarrhea (CID) is a common side effect of a number of chemotherapeutic agents. Conventional therapy for severe CID with opioids or loperamide is moderately effective. A prospective trial was conducted using octreotide acetate for treatment of severe CID refractory to loperamide.

PATIENTS AND METHODS

Thirty-two patients with grade 2 and 3 CID refractory to loperamide were treated with octreotide at a dosage of 100 microg subcutaneously 3x/day for three days followed by 50 microg 3x/day for three days. Previous chemotherapy consisted of regimens containing fluorouracil, leucovorin, CPT-11, cyclophosphamide, methotrexate and cisplatin. Primary tumors were colorectal (n = 23), gastric (n = 3), and other cancers (n = 6).

RESULTS

Complete resolution of diarrhea was obtained in 30 of 32 patients (94%); 5 within 24 hours, 14 within 48 hours, and 11 within 72 hours of treatment. Nineteen patients were treated as outpatients. Thirteen were hospitalized for a median of three days. Response was unaffected by age, gender, performance status, previous chemotherapy or primary tumor site. No side effects related to octreotide were observed.

CONCLUSIONS

Octreotide 100 microg subcutaneously 3x/day for three days is an effective, safe treatment for CID given primarily or as a second-line therapy after loperamide failure.

Management of cancer treatment-related diarrhea. Issues and therapeutic strategies

The cancer treatment-related diarrhea caused by acute graft-versus-host disease (GVHD) and chemotherapeutic agents, particularly fluoropyrimidines and irinotecan, significantly affects patient morbidity and mortality. The mechanisms causing cancer treatment-related diarrhea are not fully understood, but histopathologic evidence points to a multifactorial process that causes an absorptive and secretory imbalance in the small bowel. Cancer treatment-related diarrhea could be life-threatening, yet assessment and treatment are not currently standardized. Several clinicians participated in a closed roundtable meeting to review the mechanisms of chemotherapy-induced diarrhea (CID) and GVHD-induced diarrhea, management issues in cancer treatment-induced diarrhea, and pharmacologic approaches to treatment. The meeting produced a proposal for new treatment guidelines and an algorithm, which include the use of octreotide for the management of CID- and GVHD-induced diarrhea. The development of diarrhea assessment guidelines that expand on the current National Cancer Institute criteria and allow for better patient management was also proposed.

Negative impact of cancer chemotherapy on protein metabolism in healthy and tumor-bearing rats

Although chemotherapeutic agents are widely used in the treatment of cancer, few experimental data are available on their effects on host N metabolism. We studied the effects of a single intraperitoneal (IP) injection of cyclophosphamide ([CYP] 120 mg/kg), 5-fluorouracil ([5-FU], 50 mg/kg), cisplatinum ([CDDP], 5 mg/kg), or methotrexate ([MTX], 30 mg/kg). N balance was studied for 6 days following chemotherapy in healthy rats (n = 40) and in rats bearing Morris Hepatoma 7777 ([MH7777] n = 40) in a situation comparable to that of human cancer (tumor burden < 0.2% of body weight, moderate anorexia, and weight loss). In healthy rats, all drugs induced transient body weight loss, anorexia, and poor N balance. At day 6 posttreatment, all animals had resumed normal feed intake and positive N balance except CDDP-treated rats, which showed continued weight loss and poor N balance. CDDP and MTX exhibited antitumor activity; however, CDDP induced diarrhea in six of eight tumor-bearing rats. Drug-induced anorexia was more severe in tumor-bearing than in healthy treated rats. N balance was more severely decreased in MH7777-bearing rats than in healthy treated animals in response to 5-FU (159 +/- 36 v 273 +/- 27 mg N/2 d) and MTX (-66 +/- 36 v 153 +/- 37 mg N/2 d) at days 3 to 4 postinjection. These results establish the presence of drug-specific effects on host N balance and the existence of a drug-tumor interaction for N metabolism in the tumor-bearing host.

Have enteric infections a role in 5-fluorouracil-associated diarrhea?

In 16 advanced colorectal cancer patients with 5-fluorouracil-associated diarrhea, we evaluated the role of bacterial pathogens in the development of this adverse effect. Neither Clostridium difficile nor other pathogens were cultured from fecal specimens. These data seem to suggest that it is unlikely that intestinal infections have a role in the pathogenesis of 5FU-associated diarrhea.