Thalidomide therapy for patients with refractory Crohn's disease: an open-label trial

On the effect of thalidomide on Mycobacterium avium subspecies paratuberculosis in culture

BACKGROUND

Without known mechanisms of action, thalidomide is used to treat a variety of non-malignant 'idiopathic' diseases. There is increasing concern that Mycobacterium avium subspecies paratuberculosis (MAP) may be zoonotic. Recently, methotrexate, azathioprine, 6-mercaptopurine (6-MP), 5-aminosalicylic acid (5-ASA), cyclosporine A, rapamycin, and tacrolimus have been shown to inhibit MAP growth in culture, indicating that, unknowingly, MAP infections may have been treated for decades. We herein test the hypothesis that thalidomide may inhibit MAP growth.

METHODS

Using the radiometric 14CO2 (Bactec) system we quantified growth kinetics of thalidomide (+/-), (+), and (-) and two components for thalidomide, phthalimide and 1-hydroxypiperidine-2,6-dione (HPD). We studied four MAP strains (three human isolates, 'Ben', 'Dominic', and UCF-4, and a bovine MAP isolate 19698) and three mycobacterial controls (Mycobacterium avium and bacillus Calmette-Guérin (BCG)). Growth was quantified as growth index (GI) and inhibition as percent decrease in cumulative GI (%-DeltacGI).

RESULTS

Phthalimide had no dose-dependent inhibition on any strain. Neither thalidomide nor HPD inhibited M. avium or BCG. MAP inhibition varied; at 64 microg/ml, amongst human isolates, Dominic was most susceptible: thalidomide (+)=58%-DeltacGI and HPD=46%-DeltacGI. UCF-4 was next: thalidomide (-)=37%-DeltacGI and HPD=40%-DeltacGI. Ben was least susceptible: HPD=24%-DeltacGI.

CONCLUSIONS

We have shown, in culture, the heretofore-undescribed inhibition of MAP growth by thalidomide and its enantiomers. Phthalimide was found to have no anti-MAP activity, whereas HPD was found to inhibit MAP growth. These data are compatible with the hypothesis that thalidomide, like other 'anti-inflammatories' and 'immunomodulators' may act, in part, as an anti-MAP antibiotic.

Thalidomide in multiple myeloma--clinical trials and aspects of drug metabolism and toxicity

BACKGROUND

After the tragic events in the early 1960s, thalidomide has re-emerged as therapeutic for multiple myeloma (MM). It was first approved for the treatment of erythema nodosum leprosum, and is now under evaluation for hematologic and non-hematologic disorders. Its complex mechanism of action is not fully understood; however extensive preclinical studies in MM have revealed its antiangiogenic and immunomodulatory properties.

OBJECTIVE

In this review, we focus on the importance and toxicity of thalidomide in today's clinical use.

METHODS

Key preclinical and clinical trials available as well as data on the pharmacokinetics and pharmacodynamics of thalidomide in humans are summarized.

CONCLUSIONS

Thalidomide is widely used as first-line treatment and in relapsed/refractory MM. The most common side effects are fatigue, constipation and peripheral neuropathy, and careful monitoring is required to avoid fetal exposure.

Management of the pregnant IBD patient

Women with inflammatory bowel disease (IBD) and the physicians who care for them must make difficult decisions on issues of conception, pregnancy, and breastfeeding with very limited and often contradictory information. This review provides the most current information on the inheritance of IBD, fertility, pregnancy outcomes, the management of disease during pregnancy, and the safety of medications in pregnancy and breastfeeding. We would like to emphasize that the information presented here must be individualized to the specific situation of each patient, their acceptance of risk, and their degree of disease severity.

Effects of thalidomide in a mouse model of cerulein-induced acute pancreatitis

Current knowledge shows that pathophysiology of acute pancreatitis is characterized by intraacinar enzyme activation and subsequent dysregulation in immune response. Interactions between leukocytes, soluble mediators such as cytokines and vascular endothelium contribute to the systemic progression of the inflammatory response, whose entity may--in the end--determine disease severity and outcome. Recently, it has been shown that TNF-[alpha] may be a novel target for the treatment of acute pancreatitis; but the role of thalidomide, an immunomodulatory agent that inhibits TNF-(alpha) and angiogenesis, has not been investigated so far. The aim of the present study was to assess the effects of thalidomide in a murine model of necrotizing acute pancreatitis. Necrotizing acute pancreatitis was induced in mice by intraperitoneal injection of cerulein (hourly, x5, 50 microg/kg); in another group of animals, thalidomide was administered (200 mg/kg orally) at 1 h after first cerulein injection. After 24 h, biochemical, histological, and immunohistochemical evidences of acute pancreatitis developed in all cerulein-treated mice. On the contrary, pancreatitis histological features, amylase, lipase, TNF-alpha and IL-1beta levels, pancreas edema, and myeloperoxidase activity as well as immunohistochemical staining for inflammatory cytokines, leukocyte adhesion molecules, transforming growth factor [beta], vascular endothelial growth factor, and apoptosis-related proteins were found reduced in thalidomide-treated mice. Therefore, thalidomide treatment attenuates the development of acute pancreatitis caused by cerulein in mice. We propose that this evidence may help to clarify the role of anti-TNF-alpha and immunomodulatory agents in patients with acute pancreatitis.

Perianal fistulizing Crohn's disease: a call to action

The advent of biological therapies has focused attention on the importance of healing luminal Crohn's disease, thereby modifying the disease course. Perianal fistulas are common in Crohn's disease and often have a poor prognosis, with permanent sphincter and perineal tissue destruction. The importance of healing these fistulas has been less well appreciated. Management still often is left in surgical hands alone, rather than the optimal combination of surgery, infection control, and immunosuppression. Drug therapy often is haphazard, and the means of assessing healing over a long time period has been characterized poorly. Recent studies have suggested that many of these patients can achieve fistula healing, at least in the medium term. We therefore call for more active intervention, with the goal of healing, in these sick patients. Perianal fistulas lead to substantial physical and emotional distress because of pain, discharge, incontinence, perineal and genital disfigurement, and slow resolution even with treatment. The advent of accurate anal imaging, improved knowledge of surgical outcomes, and potent biological therapies make it timely to reflect on current best-management strategies.

Thalidomide attenuates tumor growth and preserves fast-twitch skeletal muscle fibers in cholangiocarcinoma rats

BACKGROUND

The prognosis for cholangiocarcinoma remains dismal due to a low resection rate and early recurrence. Cancer cachexia is associated with decreased survival and poor quality of life. Herein, we present a rat model of cholangiocarcinoma and demonstrate that thalidomide attenuates tumor growth and improves cachexia.

METHODS

A cholangiocarcinoma model was established using Sprague-Dawley rats that were fed thioacetamide for 40 weeks. Cholangiocarcinoma rats were treated using either thalidomide or saline for 8 weeks. Tumor growth and body weight were recorded for all animals. The expression of CD31, VEGF, and eIF4E of cholangiocarcinoma were determined using immunohistochemistry. Level of apoptosis and Fas-mediated apoptosis genes of cholangiocarcinoma were determined using TUNEL assay and ribonuclease protection assay, respectively. The distribution of fast-twitch soleus skeletal muscle fibers was determined as was the expression of TNFalpha and TGFbeta1 within soleus muscle.

RESULTS

After an 8-week treatment, the mean weight of saline- and thalidomide-treated rats was 24% and 19%, respectively, less than that of control (ANOVA, P < .05). The tumor volume (x +/-SD) of thalidomide-treated rats was less than saline-treated rats (1.9 +/- 0.4 vs 4.6 +/- 1.3 cm3, P < .01). The expression of CD31, eIF4E, and VEGF of cholangiocarcinoma was less than thalidomide-treated rats than for saline-treated rats, while the level of apoptosis of tumor cells was greater for thalidomide- treated rats than for saline-treated rats. The expression of mRNA for Fas, caspase-3, and Bax of cholangiocarcinoma in the thalidomide-treated rats was greater than for saline-treated rats. The number of fast-twitch skeletal muscle fibers per 500 mm2 of control, saline-, and thalidomide-treated rats was 43 +/- 6, 14 +/- 3, and 41 +/- 8 (ANOVA, P < .001). The expression of TNFalpha and TGFbeta1 of soleus muscles for thalidomide-treated rats was less than for saline-treated rats.

CONCLUSIONS

Using our rat cholangiocarcinoma model, we demonstrated that thalidomide inhibited tumor growth and was associated with a decrease in expression of reduced eIF4E and VEGF expression; in addition, thalidomide preserved fast-twitch skeletal muscle fibers and was associated with decreased expression of TNFalpha and TGFbeta1.

Inhibitors of NF-κB derived from thalidomide

A series of compounds originally derived from thalidomide were synthesized and evaluated. The most potent compounds in this series, 5HPP-33 and compound 20, inhibited NF-kappaB activation in HeLa cells. Preliminary study indicated that the mechanism of inhibition of NF-kappaB activation is through inhibition of its translocation from the cytoplasm to the nucleus.

Drug therapy for inflammatory bowel disease in pregnancy and the puerperium

Inflammatory bowel disease (IBD) has a peak age of onset in the 3rd decade and a peak prevalent age in the fourth decade in most studies. As a result many patients affected by Crohn's disease and ulcerative colitis are females of reproductive age interested in bearing children. It has been shown that the most important factor in the success of a pregnancy in patients with IBD is the state of disease activity. Therefore, the goal prior to and during pregnancy is to best optimise control of the disease through medical therapy. Unfortunately, many medications utilised to treat IBD are potentially toxic and/or teratogenic, leaving many physicians and patients without a clear answer as to the safest methods of therapy. This review attempts to summarise the medical literature to date, as it pertains to the safety of medical therapy for IBD during pregnancy and the puerperium.

Medical options for treating perianal Crohn's disease

Perianal Crohn's disease can cause significant morbidity for patients affected by the disease. However, diagnostic modalities and treatment options have progressed changing the goals of treatment from fistula "improvement" to complete cessation of drainage. Fistula closure and fibrosis of the fistula track is achieved in some patients. Furthermore, treatment has become a combined effort between medical physicians and surgeons. Simple disease can be treated with medical therapy alone consisting of antibiotics and immunomodulators. Infliximab should be added to refractory simple disease or simple disease with the presence of inflammation. If complex fistula disease is evident a surgical evaluation should also be done to determine if intervention is indicated. Complex disease should be treated with antibiotics, immunomodulators and biologic therapy from the onset. This review will summarise current data regarding medical options for treatment of fistulising Crohn's disease.

Current and future therapies for inflammatory bowel disease

The introduction of biologic agents to the therapeutic arsenal has dramatically impacted the way we treat patients with inflammatory bowel disease, allowing clinicians to achieve lasting remission in patients who are unresponsive to conventional therapies. New research continues to expand our understanding of the inflammatory cascade of ulcerative colitis and Crohn's disease, revealing a host of potential therapeutic targets for intervention. As we look toward the future in this rapidly developing field, we must learn how best to incorporate these new agents into the treatment algorithm to enhance or replace conventional therapies.

A randomized, double-blind, placebo-controlled trial of lenalidomide in the treatment of moderately severe active Crohn's disease

BACKGROUND

Therapy targeted at tumour necrosis factor-alpha has an established role in Crohn's disease. Lenalidomide, an analogue of thalidomide, is an oral immunomodulatory agent with powerful antitumour necrosis factor-alpha properties. It is licensed for myeloma and myelodysplastic syndrome. Based upon reports of thalidomide efficacy, lenalidomide was evaluated in Crohn's disease.

AIM

To evaluate the efficacy and safety of lenalidomide in subjects with moderately severe active Crohn's disease.

METHODS

In a multicentre, double-blind, placebo-controlled parallel group study 89 subjects were randomized to lenalidomide 25 mg daily, 5 mg daily or placebo. Subjects were treated for 12 weeks. The primary end point was a 70-point reduction in Crohn's Disease Activity Index.

RESULTS

The overall clinical response rate was not significantly different between the three groups: lenalidomide 25 mg 26%, lenalidomide 5 mg 48% and placebo 39%. Lenalidomide was generally well tolerated with only one serious adverse event, a deep vein thrombosis, being attributed to treatment.

CONCLUSION

Lenalidomide, an oral agent with antitumour necrosis factor-alpha properties, was not effective in active Crohn's disease in contrast to reports of benefit from thalidomide. The reasons for this lack of efficacy are speculative, other physiological activities may offset its action on inflammatory cytokines, or its antitumour necrosis factor-alpha action without apoptosis may be insufficient for activity in Crohn's disease.

Anti-inflammatory strategies in alcoholic steatohepatitis

The hepatotoxic effects of alcohol have been described in detail, but mechanisms underlying the hepatotoxicity have been only partially characterized. Recently, increasing lines of evidence indicate that Kupffer cells play multiple roles in initiation and progression of alcoholic steatohepatitis. After ethanol exposure, Kupffer cells are activated via a mechanism dependent on gut-derived endotoxin, and release active mediators such as proinflammatory cytokines and eicosanoids. These mediators are responsible for the pathophysiology of alcoholic steatohepatitis. This review discusses the current concept of Kupffer cell-mediated steatohepatitis and how it relates to the hypothesis on the mechanism by which alcoholic steatohepetitis is caused, as well as several key issues that have to be addressed in this field: (i) How do Kupffer cells undergo priming and activation during alcoholic steatohepatitis?; (ii) What kind of mediators are involved?; and (iii) How does the concept translate into a strategy for therapeutics of alcoholic steatohepatitis?

Inflammatory bowel disease: clinical aspects and established and evolving therapies

Crohn's disease and ulcerative colitis are two idiopathic inflammatory bowel disorders. In this paper we discuss the current diagnostic approach, their pathology, natural course, and common complications, the assessment of disease activity, extraintestinal manifestations, and medical and surgical management, and provide diagnostic and therapeutic algorithms. We critically review the evidence for established (5-aminosalicylic acid compounds, corticosteroids, immunomodulators, calcineurin inhibitors) and emerging novel therapies--including biological therapies--directed at cytokines (eg, infliximab, adalimumab, certolizumab pegol) and receptors (eg, visilizumab, abatacept) involved in T-cell activation, selective adhesion molecule blockers (eg, natalizumab, MLN-02, alicaforsen), anti-inflammatory cytokines (eg, interleukin 10), modulation of the intestinal flora (eg, antibiotics, prebiotics, probiotics), leucocyte apheresis and many more monoclonal antibodies, small molecules, recombinant growth factors, and MAP kinase inhibitors targeting various inflammatory cells and pathways. Finally, we summarise the practical aspects of standard therapies including dosing, precautions, and side-effects.

Therapeutic and prophylactic thalidomide in TNBS-induced colitis: Synergistic effects on TNF-α, IL-12 and VEGF production

AIM: To evaluated the therapeutic and prophylactic effect of thalidomide on 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Thalidomide has been reported to downregulate the expression of tumor necrosis factor α (TNF-α), IL-12, and vascular endothelial growth factor (VEGF), hallmarks of intestinal inflammation in Crohn’s disease (CD).

METHODS: Male Wistar rats were divided in five groups of ten animals each. Four groups received a rectal infusion of TNBS in ethanol. The first group was sacrificed 7 d after colitis induction. The second and third groups received either thalidomide or placebo by gavage and were sacrificed at 14 d. The fourth group received thalidomide 6 h before TNBS administration, and was sacrificed 7 d after induction. The fifth group acted as the control group and colitis was not induced. Histological inflammatory scores of the colon were performed and lamina propria CD4+ T cells, macrophages, and VEGF+ cells were detected by immunohistochemistry. TNF-α and IL-12 were quantified in the supernatant of organ cultures by ELISA.

RESULTS: Significant reduction in the inflammatory score and in the percentage of VEGF+ cells was observed in the group treated with thalidomide compared with animals not treated with thalidomide. Both TNF-α and IL-12 levels were significantly reduced among TNBS induced colitis animals treated with thalidomide compared with animals that did not receive thalidomide. TNF-α levels were also significantly reduced among the animals receiving thalidomide prophylaxis compared with untreated animals with TNBS-induced colitis. Intestinal levels of TNF-α and IL-12 were significantly correlated with the inflammatory score and the number of VEGF+ cells.

CONCLUSION: Thalidomide significantly attenuates TNBS-induced colitis by inhibiting the intestinal production of TNF-α, IL-12, and VEGF. This effect may support the use of thalidomide as an alternate approach in selected patients with CD.

Thalidomide in luminal and fistulizing Crohn's disease resistant to standard therapies

BACKGROUND

Thalidomide has been shown to be an effective treatment in Crohn's disease.

AIM

To assess the efficacy and tolerability of thalidomide in refractory Crohn's disease patients.

METHODS

Twenty-five patients were treated. Retrospective 'estimated' Crohn's Disease Activity Indices were assessed at baseline and at the end of follow-up. Clinical response was defined as symptomatic improvement and a reduction in the 'estimated' Crohn's Disease Activity Index of >100 points, > or =50% reduction in draining fistulas or clinical improvement in perianal ulcers. Clinical remission was defined as symptom resolution and an 'estimated' Crohn's Disease Activity Index <150, complete fistula closure or complete ulcer healing.

RESULTS

Six of eight patients treated for luminal disease responded to thalidomide at a median follow-up of 12 months (three clinical responses, three clinical remissions). The median reduction in 'estimated' Crohn's Disease Activity Index was 212 points (P = 0.005). Nine of 11 patients with active fistulizing disease responded to thalidomide (six responses; three remissions). The four patients treated for both luminal and fistulizing disease had fistula response. Three of them had a response in luminal disease activity. One of two patients with ulcerating perianal disease responded. Twelve patients discontinued treatment because of adverse effects (three sedation; two abdominal pain; one leucopoenia; six neuropathy).

CONCLUSION

Thalidomide is an effective short- to medium-term treatment in selected patients with refractory luminal and fistulizing Crohn's disease. Its long-term use is limited by toxicity.

Efficacy and safety of thalidomide in children and young adults with intractable inflammatory bowel disease: long-term results

BACKGROUND

Anti-tumour necrosis factor-alpha antibodies are useful for the treatment of refractory Crohn's disease and ulcerative colitis. Thalidomide is another agent with tumour necrosis factor-alpha suppressive properties.

AIM

To investigate the long-term efficacy and safety of thalidomide in a group of children and young adults with refractory inflammatory bowel disease.

METHODS

Twenty-eight patients with refractory moderate-severe inflammatory bowel disease (19 Crohn's disease, 9 ulcerative colitis) received thalidomide 1.5-2.5 mg/kg/day. Patients were assessed at baseline, at weeks 2, 4, 8 and 12, and then every 12 weeks by patient's diary, physical examinations, laboratory analyses and scoring on activity indexes. Primary outcomes were: (i) efficacy in inducing remission; and (ii) efficacy in maintaining remission.

RESULTS

Remission was achieved with thalidomide in 21 of 28 (75%) patients (17 with Crohn's disease, 4 with ulcerative colitis). Mean duration of remission was 34.5 months. Sixteen of 20 (80%) patients suspended steroids. Reversible neuropathy occurred in seven of 28 (25%) patients, but only with cumulative doses over 28 g. Other side effects requiring thalidomide suspension were vertigo/somnolence (one of 28), and agitation/hallucinations (one of 28).

CONCLUSIONS

Thalidomide seems to be effective in inducing long-term remission in children and adolescents with intractable inflammatory bowel disease. Neuropathy is the main adverse effect, but appears to be cumulative dose-dependent, thus allowing long-term remission before drug suspension.

Current therapy of inflammatory bowel disease in children

Ulcerative colitis (UC) and Crohn disease (CD) are chronic intestinal inflammatory diseases that can present as bloody diarrhea, abdominal pain, and malnutrition. Collectively, these disorders are referred to as inflammatory bowel disease (IBD). All patients with IBD share a common pathophysiology. However, there are a number of developmental, psychosocial, and physiologic issues that are unique to the approximate, equals 20% of patients that present during childhood or adolescence. These include the possibility of disease-induced delays in linear growth or physical development, differences in drug dosing, and the changes in social and cognitive development that occur as children move from school-age years into adolescence and early adulthood. Gastroenterologists caring for these children must therefore develop an optimal regimen of pharmacologic therapies, nutritional management, psychologic support, and properly timed surgery (when necessary) that will maintain disease remission, minimize disease and drug-induced adverse effects, and optimize growth and development. This article reviews current approaches to the management of patients with UC and CD and highlights issues specific to the treatment of children with IBD. The principal medical therapies used to induce disease remission in patients with UC are aminosalicylates (for mild disease), corticosteroids (for moderate disease), and cyclosporine (ciclosporin) (for severe disease). If a patient responds to the induction regimen, maintenance therapies that are used to prevent disease relapse include aminosalicylates, mercaptopurine, and azathioprine. Colectomy with creation of an ileal pouch anal anastomosis (J pouch) has become the standard of care for patients with severe or refractory colitis and results in an improved quality of life in most patients. Therefore, the risks associated with using increasingly potent immunosuppressant agents must be balanced in each case against a patient's desire to retain their colon and avoid a temporary or potentially permanent ileostomy. Decisions about drug therapy in the management of patients with CD are more complex and depend on both the location (e.g. gastroduodenal vs small intestinal vs colonic), as well as the behavior of the disease (inflammatory/mucosal vs stricturing vs perforating) in a given patient. Induction therapies for CD typically include aminosalicylates and antibiotics (for mild mucosal disease), nutritional therapy (including elemental or polymeric formulas), corticosteroids (for moderate disease), and infliximab (for corticosteroid-resistant or fistulizing disease). Aminosalicylates, mercaptopurine, azathioprine, methotrexate, and infliximab can be used as maintenance therapies. Because surgical treatment of CD is not curative, it is typically reserved for those patients either with persistent symptoms and disease limited to a small section of the intestine (e.g. the terminal ileum and cecum) or for the management of complications of the disease including stricture or abdominal abscess. When surgery is necessary, maintenance medications administered postoperatively will postpone recurrence. Patients with UC and CD are at risk for the development of micronutrient deficiencies (including folate, iron, and vitamin D deficiencies) and require close nutritional monitoring. In addition, patients with UC and CD involving the colon are at increased risk of developing colon cancer, and should be enrolled into a colonoscopy surveillance program after 8-10 years of disease duration.

Drug therapy of inflammatory bowel disease in fertile women

Inflammatory bowel disease (IBD) is a disease that affects women of childbearing age. Active disease at conception increases the risk for adverse outcomes and thus postponement of pregnancy until the disease is in remission is the best advice that physicians can give their IBD patients. The majority of medications used to treat IBD are safe in pregnancy and breastfeeding; active, untreated, or undertreated disease is more deleterious than active therapy.

Infliximab in fistulizing Crohn's disease

The treatment of fistulizing CD has evolved greatly in the last 15 years, largely caused by improvements in medical therapy. Tables 2 and 3 summarize all published controlled and uncontrolled trials of immunomodulator and biologic therapy for the treatment of Crohn's fistulae. The advent of immunomodulators and anti-TNF-alpha agents has transformed the treatment of Crohn's fistulae from almost exclusively surgical to placing a much larger emphasis on medical therapy, either as initial therapy alone, with surgery reserved for refractory cases, or in combination with surgery from the start. For this reason, surgeons and gastroenterologists must work in concert to provide the best care for each patient. Proper fistula management also relies heavily on accurate diagnosis, especially defining the anatomy of the fistula, ascertaining whether abscess formation is present, and determining the location and extent of intestinal inflammation.

Apoptosis as a therapeutic tool in IBD?

Defective apoptosis of mucosal cell populations seems to be a relevant pathogenetic mechanism in inflammatory bowel disease (IBD). It has been suggested that the induction of apoptosis in various effector cells may be a relevant therapeutic mechanism in IBD. Indeed, it was shown that different drugs used for treatment of IBD have the capacity to induce apoptosis in T cells or monocytes in vitro and in vivo. However, it remains unclear whether these observations are related to clinical efficacy of these agents. TNF-alpha is one of the most relevant proinflammatory mediators in IBD and anti-TNF treatment has been shown to be of particular benefit for patients with IBD. It could subsequently be shown that various anti-TNF-alpha agents, such as infliximab and adalimumab, can induce apoptosis in activated monocytes and lymphocytes in vitro and in vivo. This mechanism requires reverse signaling via transmembranous TNF, thereby eliciting a signal transduction cascade that results in programmed cell death. Although other mechanisms might also contribute to the clinical effect of anti-TNF-alpha, current data suggest that apoptosis is a relevant mechanism that is associated with clinical efficacy of anti-TNF agents. Induction of apoptosis in activated monocytes or T cells may be regarded as therapeutic tool not only for anti-TNF agents, but also for other drugs used in IBD. Future strategies should focus on identification of mechanisms that prevent apoptosis in the mucosa of patients with IBD and in targeting apoptotic pathways as a therapeutic strategy in IBD.

Preparation and in vitro analysis of microcapsule thalidomide formulation for targeted suppression of TNF-alpha

Recent studies have implicated the cytokine tumor necrosis factor-alpha (TNF-alpha) in the inflammation associated with Crohn's disease (CD). Thalidomide has been shown to decrease this inflammation by the suppression of TNF-alpha secretion. However, side effects associated with thalidomide have precluded its widespread usage. In the present study we investigated the efficacy of a "targeted delivery approach" for thalidomide at the site of inflammation. We observed that alginate-poly-l-lysine-alginate (APA) polymer-based microcapsule formulations that encapsulate thalidomide could be designed. These capsules could be delivered at target sites where they almost entirely suppress TNF-alpha secretion in lipopolysaccharide activated RAW 264.7 macrophage cells in vitro. These findings indicate that targeted delivery of thalidomide using APA capsules could facilitate its usage in reducing the inflammation associated with chronic conditions such as Crohn's disease and ulcerative colitis.

New therapies for the treatment of inflammatory bowel disease

Medical therapy of IBD has made remarkable progress in recent years, driven forward by new knowledge about mechanisms of disease and advances in biotechnology. As we continue to learn about how best to use the agents currently in our hands, the addition of new drugs will further improve outcomes, and will bring new insights into the fundamental causes of these diseases.

Medical therapy for refractory pediatric Crohn's disease

Crohn's disease is a common indication for referral to pediatric gastroenterology. While most patients with Crohn's disease respond to standard induction therapy, steroid-refractory or steroid-dependent disease is a frequently encountered problem. This review discusses the data existing in both the adult and pediatric literature for medical therapy of refractory pediatric Crohn's disease.

Toxicity profile of the immunomodulatory thalidomide analogue, lenalidomide: phase I clinical trial of three dosing schedules in patients with solid malignancies

Thalidomide is an anti-angiogenic agent currently used to treat patients with malignant cachexia or multiple myeloma. Lenalidomide (CC-5013) is an immunomodulatory thalidomide analogue licensed in the United States of America (USA) for the treatment of a subtype of myelodysplastic syndrome. This two-centre, open-label phase I study evaluated dose-limiting toxicities in 55 patients with malignant solid tumours refractory to standard chemotherapies. Lenalidomide capsules were consumed once daily for 12 weeks according to one of the following three schedules: (I) 25 mg daily for the first 7 d, the daily dose increased by 25 mg each week up to a maximum daily dose of 150 mg; (II) 25mg daily for 21 d followed by a 7-d rest period, the 4-week cycle repeated for 3 cycles; (III) 10 mg daily continuously. Twenty-six patients completed the study period. Two patients experienced a grade 3 hypersensitivity rash. Four patients in cohort I and 4 patients in cohort II suffered grade 3 or 4 neutropaenia. In 2 patients with predisposing medical factors, grade 3 cardiac dysrhythmia was recorded. Grade 1 neurotoxicity was detected in 6 patients. One complete and two partial radiological responses were measured by computed tomography scanning; 8 patients had stable disease after 12 weeks of treatment. Fifteen patients remained on treatment as named patients; 1 with metastatic melanoma remains in clinical remission 3.5 years from trial entry. This study indicates the tolerability and potential clinical efficacy of lenalidomide in patients with advanced solid tumours who have previously received multi-modality treatment. Depending on the extent of myelosuppressive pre-treatment, dose schedules (II) or (III) are advocated for large-scale trials of long-term administration.

American gastroenterological association institute technical review on the use of gastrointestinal medications in pregnancy

This literature review and the recommendations therein were prepared for the American Gastroenterological Association Institute Clinical Practice and Economics Committee. The paper was approved by the Committee on February 22, 2006 and by the AGA Institute Governing Board on April 20, 2006.

Role of angiogenesis in inflammatory bowel disease

Several studies have shown alterations in vascular anatomy and physiology in inflammatory bowel disease (IBD). These findings, together with the observed upregulation of the mediators of angiogenesis in IBD patients, suggest that angiogenesis possibly contributes to the initiation and perpetuation of IBD. There is considerable evidence of an interrelationship between the mechanisms of angiogenesis and chronic inflammation in IBD. The increased expression of endothelial junction adhesion molecules found in IBD patients indicates the presence of active angiogenesis. Evidence that angiogenesis is involved in IBD was also obtained from animal models of colitis, most notably from studies of angiogenesis inhibition. Serum levels of vascular endothelial growth factor (VEGF) correlate with disease activity in human IBD and fall with the use of steroids, thalidomide, or infliximab. Pharmacological inhibition of angiogenesis, therefore, has the potential to be a therapeutic strategy in IBD. This review outlines the evidence that the rate of angiogenesis is increased in the inflamed intestine in IBD and proposes lines for future research in this field.

A thalidomide analogue with in vitro antiproliferative, antimitotic, and microtubule-stabilizing activities

We discovered a thalidomide analogue [5-hydroxy-(2,6-diisopropylphenyl)-1H-isoindole-1,3-dione (5HPP-33)] with antiproliferative activity against nine cancer cell lines in vitro. Flow cytometric analyses showed that the compound caused G2-M arrest, which occurred mainly at the mitotic phase. In addition, immunofluorescence microscopy and in vitro tubulin polymerization studies showed that 5HPP-33 has antimicrotubule activity with a paclitaxel-like mode of action. It is effective against four different paclitaxel-resistant cell lines. Thus, 5HPP-33 represents a potential antitumor agent.

Hereditary auto-inflammatory disorders and biologics

The term auto-inflammatory disorders has been coined to describe a group of conditions characterized by spontaneously relapsing and remitting bouts of systemic inflammation without apparent involvement of antigen-specific T cells or significant production of auto-antibodies. The hereditary periodic fever syndromes are considered as the prototypic auto-inflammatory diseases, and genetic studies have yielded important new insights into innate immunity. DNA analysis has greatly enhanced the clinical characterization of these conditions, and elucidation of their molecular aetiopathogenesis has suggested that therapies may be aimed at specific targets within the immune cascade. The availability of biologic response modifiers such as inhibitors of tumour necrosis factor (TNF) and interleukin-1beta has greatly improved the outlook for some of these disorders, although effective therapies remain elusive in patients with certain conditions, including hyperimmunoglobulinaemia-D with periodic fever syndrome (HIDS) and a proportion of those with TNF-receptor associated periodic syndrome (TRAPS). Indeed, outstanding challenges and the unique potential to further elucidate molecular mechanisms in innate immunity are illustrated by the dashed early hope that TNF blockade would be a panacea for TRAPS: not only is etanercept (Enbrel) ineffective in some cases, but there are anecdotal reports of this condition being greatly exacerbated by infliximab (Remicade).

Anti-nociceptive effect of thalidomide on zymosan-induced experimental articular incapacitation

The anti-nociceptive effect of thalidomide on zymosan-induced articular knee joint incapacitation in rats was investigated. Thalidomide (5-45 mg/kg), given 30 min before but not 2 h after the intra-articular injection of zymosan, inhibited the nociceptive response in a dose-dependent manner. Furthermore, thalidomide pretreatment significantly reduced the concentration of tumor necrosis factor-alpha (TNF-alpha, -68.4%) in the exudate of zymosan-injected joints, but not those of interleukin-1beta, interleukin-6, CINC-1 or interleukin-10. The expression of TNF-alpha, determined by immunohistochemical staining, in synovial tissues obtained from articular joints injected with zymosan was also inhibited by thalidomide pretreatment. The anti-nociceptive effect of thalidomide was not reversed by the co-administration of an opioid receptor antagonist, naloxone, suggesting that endogenous opioids do not mediate the anti-nociceptive effect of thalidomide in this model. In conclusion, the anti-nociceptive activity of thalidomide in zymosan-induced articular incapacitation is associated with the inhibition of TNF-alpha by resident synovial cells.

Evolving knowledge and therapy of inflammatory bowel disease

With recent advances in the understanding of its pathophysiology, inflammatory bowel disease has become a very active area for the development of novel therapeutic agents. New targets for biologics include cytokines involved in T-cell activation, with antibodies directed against IL-12 and interferon-gamma. Selective adhesion molecule blockade has produced promising, though mixed, results. Recombinant human granulocyte-macrophage colony-stimulating factor might be effective in active Crohn's disease, presumably through stimulation of intestinal innate immune responses. With increasing evidence for a crucial role for luminal flora in maintaining the health of the bowel, strategies to manipulate intestinal bacteria using probiotics and prebiotics are being actively investigated as well.

Anti-fibrotic effects of thalidomide on hepatic stellate cells and dimethylnitrosamine-intoxicated rats

Tumor necrosis factor-alpha (TNF-alpha) plays a central role in cellular necrosis, apoptosis, organ failure, tissue damage, inflammation and fibrosis. These processes, occurring in liver injury, may lead to cirrhosis. Thalidomide, alpha-N-phthalidoglutarimide, (C(13)H(10)N(2))(4), has been shown to have immunomodulatory and anti-inflammatory properties, possibly mediated through its anti-TNF-alpha effect. In this study, we investigated the in vitro and in vivo effects of thalidomide on hepatic fibrosis. A cell line of rat hepatic stellate cells (HSC-T6) was stimulated with transforming growth factor-beta1 (TGF-beta1) or TNF-alpha. The inhibitory effects of thalidomide on the NFkappaB signaling cascade and fibrosis markers including alpha-smooth muscle actin (alpha-SMA) and collagen, were assessed. An in vivo therapeutic study was conducted in dimethylnitrosamine (DMN)-treated rats, which were randomly assigned to 1 of 4 groups: vehicle (0.7% carboxyl methyl cellulose, CMC), thalidomide (40 mg/kg), thalidomide (200 mg/kg), or silymarin (50 mg/kg), each given by gavage twice daily for 3 weeks starting after 1 week of DMN administration. Thalidomide (100-800 nM) concentration-dependently inhibited NFkappaB transcriptional activity induced by TNF-alpha, including IKKalpha expression and IkappaBalpha phosphorylation in HSC-T6 cells. In addition, thalidomide also suppressed TGF-beta1-induced alpha-SMA expression and collagen deposition in HSC-T6 cells. Fibrosis scores of livers from DMN-treated rats receiving high dose of thalidomide (0.89 +/- 0.20) were significantly reduced in comparison with those of DMN-treated rats receiving vehicle (1.56 +/- 0.18). Hepatic collagen contents of DMN rats were also significantly reduced by either thalidomide or silymarin treatment. Immunohistochemical double staining results showed that alpha-SMA- and NFkappaB-positive cells were decreased in the livers from DMN rats receiving either thalidomide or silymarin treatment. In addition, real-time PCR analysis indicated that hepatic mRNA expressions of TGF-beta1, alpha-SMA, collagen 1alpha2, TNF-alpha and iNOS genes were attenuated by thalidomide treatment. In conclusion, our results showed that thalidomide inhibited activation of HSC-T6 cells by TNF-alpha and ameliorated liver fibrosis in DMN-intoxicated rats.

Complications of biological therapy for inflammatory bowel diseases

PURPOSE OF REVIEW

The purpose of this review is to analyze the complications associated with treatment of inflammatory bowel disease with biologic agents.

RECENT FINDINGS

There have been various biologic agents evaluated in patients with inflammatory bowel disease; that is, Crohn's disease and ulcerative colitis. Thus far only infliximab has been approved by the US Food and Drug Administration as induction and maintenance treatment in patients with active Crohn's disease (moderate-to-severe and/or fistulizing) who are refractory to conventional therapy. Recent data from two large multicenter, multicountry, randomized controlled clinical trials have demonstrated that infliximab is efficacious also for the treatment of ulcerative colitis. Other biologics considered potentially efficacious are still undergoing evaluation in various clinical trials.

SUMMARY

The data concerning biologics' associated toxicity in patients with inflammatory bowel disease are the most robust in the case of infliximab. These data are derived from both prospective, randomized clinical trials and from post-marketing experience. In the case of the remaining agents the data concerning safety in inflammatory bowel disease are limited, as these agents were not evaluated in as many trials as infliximab; indeed, some of them included only several patients.

New cytokine therapeutics for inflammatory bowel disease

Conventional therapy for inflammatory bowel diseases rely on corticosteroids and 5-aminosalicylates combined with immunosuppressive agents for maintenance. These drugs are not always effective and may inflict serious side effects. Other therapies are therefore awaited. Infliximab, a monoclonal antibody against the pro-inflammatory cytokine TNF-alpha has been successfully applied as a treatment for Crohn's disease. The mechanism of action of this drug extends beyond the level of TNF-alpha scavenging and includes induction of apoptosis of effector cells. Numerous anti-TNF antibodies have been developed and are currently evaluated in clinical trials. Other targets for monoclonal antibodies include integrins and cytokines involved in T-cell differentiation and activation. Likewise recombinant proteins that moderate TNF bioactivity and lymphocyte function have been developed. The therapeutic effect of recombinant interleukin-10 seems to be dependent on local delivery of the protein. Antisense therapy targeting lymphocyte migration has also been tested in IBD. Finally, the conventional drug thalidomide and possibly MAP-kinase inhibitors may become novel treatment entities for IBD.

[TNF-alpha inhibitors in inflammatory bowel disease]

Inflammatory bowel disease (IBD) is a chronic immunoinflammatory response to an stimulus that activates a chain of cellular mediators causing intestinal damage. One of the most well recognized proinflammatory mediators involved in the pathogenesis of IBD is tumor necrosis factor alpha (TNFalpha). The treatment of IBD has advanced in parallel to the improvement of the knowledge of its physiopathology, leading to the development of biological therapies. An example of this kind of treatment is the use of substances that antagonize TNFalpha, such as monoclonal antibodies infliximab, adalimumab, natalizumab, etanercept or onercept, with infliximab being the unique approved for use in IBD. Several studies have demonstrated that inhibition of TNFalpha is useful in the treatment of Crohn's disease (CD). In CD, infliximab induces the remission of relapses which are refractory to the conventional treatment, prevents more relapses and induces a closure of enterocutaneous and perianal fistula that do not respond to first line treatment. However, infliximab is not useful in ulcerative colitis. Infliximab treatment has some drawbacks, such as the development of anti-infliximab antibodies, which cause a loss of efficacy of the treatment and hypersensitivity reactions. Other reported adverse effects of infliximab are the development of autoimmunity, such as that related with antinuclear or anti-DNA antibodies, or the reactivation of infections such as tuberculosis. In fact, a screening for tuberculosis is necessary before administration of infliximab. To reduce the adverse effects due to infliximab immunogenicity, several trials with humanized or completely human agents, such as adalimumab or onercept, are under way. Until the precise stimulus that triggers IBD is identified, biological therapies have a great future and the selective antagonism of TNFalpha is already a reality.

Recent developments in the pharmacological treatment of Crohn’s disease

Therapy for Crohn's disease (CD) is rapidly evolving with the emergence of new discoveries in disease pathogenesis. Since the approval of the first biological agent, infliximab, there have been several others that have been studied and are available for use within the context of clinical trials, in CD patients who do not respond to conventional medications or whose disease cannot be maintained in remission with the use of infliximab. The number of available drugs that have focused on the inhibition of TNF is growing. To avoid the injectable route of administering biologicals, several oral agents, such as thalidomide analogues, nonabsorbable antibiotics, such as rifaximin, and specific antibiotics, such as ornidazole, are being studied and considered for patients with CD. Hormonal therapies, such as growth hormone, coherin, medroxyprogesterone acetate and dehydroepiandrosterone, are other novel therapies for CD. Immunomodulators in use in other fields of medicine, including tacrolimus, 6-thioguanine and leflunomide, are being evaluated for the treatment of patients with CD and are also discussed. Several other promising therapies, such as cyclophosphamide, extracorporeal photochemotherapy, stem cell transplantation and the use of porcine whipworm, add to the available therapeutic armamentarium of this life-long remitting and relapsing disease. The future for CD patients is promising with the ever-expanding repertoire of drugs that are being studied.

Mechanism of TNF-{alpha} modulation of Caco-2 intestinal epithelial tight junction barrier: role of myosin light-chain kinase protein expression

TNF-alpha plays a central role in the intestinal inflammation of various inflammatory disorders including Crohn's disease (CD). TNF-alpha-induced increase in intestinal epithelial tight junction (TJ) permeability has been proposed as one of the proinflammatory mechanisms contributing to the intestinal inflammation. The intracellular mechanisms involved in the TNF-alpha-induced increase in intestinal TJ permeability remain unclear. The purpose of this study was to investigate the possibility that the TNF-alpha-induced increase in intestinal epithelial TJ permeability was regulated by myosin light-chain kinase (MLCK) protein expression, using an in vitro intestinal epithelial model system consisting of the filter-grown Caco-2 intestinal epithelial monolayers. TNF-alpha (10 ng/ml) produced a time-dependent increase in Caco-2 MLCK expression. The TNF-alpha increase in MLCK protein expression paralleled the increase in Caco-2 TJ permeability, and the inhibition of the TNF-alpha-induced MLCK expression (by cycloheximide) prevented the increase in Caco-2 TJ permeability, suggesting that MLCK expression may be required for the increase in Caco-2 TJ permeability. The TNF-alpha increase in MLCK protein expression was preceded by an increase in MLCK mRNA expression but not an alteration in MLCK protein degradation. Actinomycin-D prevented the TNF-alpha increase in MLCK mRNA expression and the subsequent increase in MLCK protein expression and Caco-2 TJ permeability, suggesting that the increase in MLCK mRNA transcription led to the increase in MLCK expression. The TNF-alpha increase in MLCK protein expression was also associated with an increase in Caco-2 MLCK activity. The cycloheximide inhibition of MLCK protein expression prevented the TNF-alpha increase in MLCK activity and Caco-2 TJ permeability. Moreover, inhibitors of MLCK, Mg(2+)-myosin ATPase, and metabolic energy prevented the TNF-alpha increase in Caco-2 TJ permeability, suggesting that the increase in MLCK activity was required for the TNF-alpha-induced opening of the Caco-2 TJ barrier. In conclusion, our results indicate for the first time that 1) the TNF-alpha increase in Caco-2 TJ permeability was mediated by an increase in MLCK protein expression, 2) the increase in MLCK protein expression was regulated by an increase in MLCK mRNA transcription, and 3) the increase in Caco-2 TJ permeability required MLCK protein expression-dependent increase in MLCK activity.

Efficacy of conventional immunosuppressive drugs in IBD

The introduction and rapid diffusion of biological agents in the treatment of inflammatory bowel disease had led us to believe that the old immunosuppressive drugs were destined to disappear. However, despite a decade of clinical experience in the use of biological agents, the old immunosuppressive drugs continue to play a pivotal role in the management of inflammatory bowel disease. Various factors may account for this change of view. Aim of the present review was to summarise key information currently available regarding the use of immunosuppressive drugs in the treatment of inflammatory bowel disease.

Review article: chronic active disease and maintaining remission in Crohn's disease

The clinical management of Crohn's disease can be considered in relation to the treatment of acute disease and the maintenance of remission. The medication used to achieve these two goals may or may not be the same. Some patients with mildly active disease may respond to high-dose (4 g/day) mesalazine (mesalamine), and 5-aminosalicylic acid may also be helpful in weaning a patient off steroids after treatment for a flare-up. However, the value of 5-aminosalicylic acid in maintaining remission in Crohn's disease remains controversial. Subgroups of patients may be helped: for example, patients with Crohn's disease who have experienced a relapse within the last 2 years may benefit. Steroids form the first-line therapy for acute episodes of inflammation but do not maintain remission. Azathioprine and mercaptopurine are the first-line drugs for the maintenance of remission in moderate to severe Crohn's disease, and by titrating the dose up from 2 mg/kg daily, some previously resistant patients will be brought into remission. One-half of patients who do not tolerate azathioprine will tolerate mercaptopurine. Methotrexate is effective in inducing and maintaining remission, and is useful for patients who fail azathioprine treatment. Thalidomide is not proven in controlled studies, but two open studies have demonstrated its efficacy. The optimal dose, however, remains to be defined. Purified liquid diets with food exclusion can induce remission in patients with active disease, but food exclusion is difficult to maintain long term. Infliximab can induce and maintain remission in patients resistant to other therapies, with two-thirds of patients initially responding to treatment. One-third go into remission and, of those who respond to a single treatment, approximately one-half maintain remission when treated regularly for a year. Infliximab is, however, associated with an increased risk of infection, and its effect on cancer incidence is uncertain. The development of antibodies against the drug is associated with a loss of effect and allergic infusion reactions. In summary, simple proven therapies should be used first, because of their safety and benefit in some patients. However, aggressive therapy should be used when needed.

Thalidomide salvages lethal hepatic necroinflammation and accelerates recovery from cirrhosis in rats

BACKGROUND/AIMS

The authors investigated the feasibility of thalidomide employed to treat liver fibrosis.

METHODS

A cirrhotic model was established using Sprague-Dawley rats fed thioacetamide. Thalidomide-treated group was given thalidomide (10mg/kg/day) intraperitoneally for 10 consecutive days. Mortality, histopathological changes, TNFalpha, TGFbeta1, TIMP-1 and TIMP-2 were determined. Expression of TNFalpha and TGFbeta1 mRNA of Kupffer's cells derived from the experimental rats were determined.

RESULTS

The mortality rates of thalidomide-treated group and vehicle-treated group were 8 and 32%, respectively. The total Knodell score of thalidomide-treated rats was lower than those of vehicle-treated rats. Micro-nodular cirrhosis resolved grossly in thalidomide-treated rats on day 28; while vehicle-treated rats continued to display uneven liver surface on day 28. Expression of TNFalpha, TGFbeta1, TIMP-1, and TIMP-2 was decreased in thalidomide-treated rats compared to those treated with vehicles. Finally, the expression of TNFalpha and TGFbeta1 mRNA of Kupffer's cells derived from rats treated with thalidomide were much lower than those treated with vehicle.

CONCLUSIONS

Thalidomide salvages lethal hepatic necroinflammation, accelerates recovery from cirrhosis in rats, and works by suppressing of TNFalpha and TGFbeta1 production of Kupffer's cells.

Management of ulcerative colitis and Crohn's disease

The conventional medical treatment of IBD consists of aminosalicylates, corticosteroids, immunosuppressive drugs (azathioprine, 6-mercaptopurin, methotrexate, cyclosporin) and antibiotics. The only drugs able to modify the disease course are azathioprine, its metabolite 6-mercaptopurin and methotrexate. However, these drugs have a slow onset of action and are associated with important side-effects in some patients, necessitating the discontinuation of the drug. Moreover, up to 60% of patients do not respond to these drugs long-term. Fortunately, the management of IBD has entered a new era in the beginning of the 1990s with the development of new biological therapies, selectively blocking the inflammatory cascade. The novel molecules have arisen from the increasing knowledge about the disease pathogenesis and their production has been precipitated by the techniques of molecular biology. Infliximab, the first available biological for Crohn's disease has certainly revolutionised standard treatment. Because of its profound clinical, endoscopic and histological effects, the standard step up approach in the treatment of IBD has been challenged. A large array of new rationally designed biologicals, with a better safety profile and equally selectively acting is underway, and is likely to change our current practise even more dramatically in the next decade.

Perianal Crohn's disease

BACKGROUND

The management of perianal Crohn's disease is difficult. A wide variety of treatment options exist although few are evidence based.

METHODS

A search was conducted using the National Library of Medicine for articles on perianal Crohn's disease and its incidence, classification, assessment and management.

RESULTS AND CONCLUSION

Perianal Crohn's disease can manifest as skin tags, ulcers, fissures, abscesses, fistulas or stenoses. Improved radiological imaging with endoanal anal ultrasonography and magnetic resonance imaging has improved its assessment and may be used to predict outcome after surgery. Many treatment options exist. During acute complications they are generally aimed at resolving the immediate problem and limiting damage to anal and perianal tissues; this may be a 'bridge' to definitive treatment. The likelihood of success of definitive treatment must be weighed against the risk of complications, especially faecal incontinence.

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