Previous studies have been indicated that melatonin may be act via multiple functions such as reproduction, enhancement of immunomodulation, antioxidant defense, and anti-inflammatory properties. The anti-inflammatory activity of melatonin could be helpful in the treatment of chronic inflammatory diseases such as UC (
8). The site of inflammation in this disease is mucosa and submucosa of the colon wall, and mainstay of treatment in mild to moderate UC is mesalamine compounds which modulate local chemical mediators of the inflammatory response and is also postulated to be a local free radical scavenger or inhibitor of tumor necrosis factor in the intestinal wall. Of course, they must bypass the stomach and small intestine and reach the colon finally (
14,
15). Although oral melatonin absorbs in the GI tract, absorption in the stomach is the least and the most significant absorption in the rectum and ileum, respectively (
16). So it’s logical to administer oral melatonin in the treatment of UC.
Several animal trials have been conducted regarding the effect of oral and rectal administration of melatonin on the suppression of UC, but to the best of our knowledge, there is only one randomized, double-blind clinical trial that evaluated the effects of melatonin 5mg/d as adjuvant treatment of UC which have done by Chojnacki
et al. (
7). In Chojnacki
et al. study, only assessment of clinical response, anxiety degree, and CRP have been evaluated as the main outcome. We have evaluated the effect of oral melatonin as an adjunctive therapy of UC patients too, but we have considered three different components, including clinical marker (SSCAI), biochemical markers (FC, CRP, and ESR), and quality of life (using SF-36). At the baseline there is not any significant difference between the melatonin and placebo groups regarding any of the above parameters (clinical, biochemical, and quality of life). In other words it seems that both groups are matched, and there is not any confounding factor.
At the end of the study, the difference in clinical activity index in the two groups was one of the most interesting findings of our trail where by using SSCAI, melatonin group had a better index than the placebo group (
p = 0.030). Chojnacki
et al. have been evaluated clinical status of UC patients by using Mayo Clinical Disease Activity Index (MCDAI). They have reported that melatonin group had a better index compared with placebo group (
p = 0.02) (
7). Although several indices for UC activity have been developed, there is not any gold standard amongst them (
17). There is no acknowledged metric for comparing indices, which vary in their scale of scores and the data collected. Agreement between disease activity categories assigned for each index and the clinical category assigned by a physician with access to all data beyond that recorded by any individual index, were 61% and 67% for the SCCAI and MCDAI respectively. In addition SCCAI does not need physician estimation, laboratory tests or invasive test against the MCDAI. Since SCCAI compared with MCDAI is a purely clinical index for UC patients (
18), we prefer to use SCCAI as a clinical marker for assessment in our trial. Concern to our trial and Chojancki
et al. study, melatonin could be recommended as an adjunctive therapy for optimizing a better clinical index in UC patients.
The recent guideline of the American College of Gastroenterology (ACG) has mentioned that FC can be used in patients with UC as a noninvasive biomarker of disease activity and to assess response to treatment and relapse (
18). In previous trial regarding effect of melatonin in UC patients, FC has not been assayed (
7) and our trial is the first one to compare effect of melatonin versus placebo on FC level in UC patients. Our results showed that FC level decreased significantly in melatonin group compared with placebo group (
p = 0.004).
In the current study, ESR and CRP did not significantly differ between the two groups (
p = 0.697 and
p = 0.112, respectively). Although the result of Chojancki et al trial demonstrated declined CRP in melatonin group versus placebo group significantly (
7), it is important that unlike the FC, both ESR and CRP are non-specific for evaluation of UC solely (
19). Theede
et al. study indicated that FC levels are more sensitive and specific than ESR and CRP in assessment of UC severity (
20). Moreover one study looking at the correlation between CRP or ESR and colonscopic activity in patients with UC revealed that there is only a very modest correlation between them and unlike FC, ESR and CRP could not be considered as an assay biomarker (
21).
In a meta-analysis, Yarlas
et al. have studied the burden of UC on patients’ quality-of-life by synthesizing data from studies comparing scores from the SF-36 between UC patients and matched reference samples. They have been concluded that UC patients with active disease experience burdens on physical, emotional, and social functioning and well-being, and that normalization of these outcomes is observed in patients with inactive UC (
22). So we have compared SF-36 between melatonin and placebo groups in UC patients for the first time. The result of our study indicated better scores in some of subdomain such as role-emotional, energy, and general health in melatonin compared with the placebo group significantly (
p = 0.050,
p = 0.002, and
p = 0.037, respectively). A number of studies have been reported better quality of life by administration of melatonin in other diseases. For example, Russcher
et al. have demonstrated that in hemodialysis patients, melatonin 3 mg/d could enhanced general mental health versus placebo (
p = 0.05). Also emotional role activities and last year’s health change tended to improve with melatonin (difference 29.8% and difference 14.6% respectively) (
23). Grima
et al. have been evaluated effect of melatonin 2 mg/d versus placebo in sleep disturbances and quality of life in patients with traumatic brain injury. With respect to SF-36, melatonin improved self-reported vitality and mental health. Of course melatonin was not associated with important changes on the other six domains of the SF-36 (
24).
In our study, only one patient has been excluded from the study because of possible severe nightmares related to the placebo. The patients reported no severe adverse drug reaction either by melatonin or placebo group in the present study, a consonant finding with previous studies which used the same dose of melatonin (3 mg/d) for the other purposes (
25,
26). In Chojancki
et al. study, some participants reported recurrent headaches felt, but probably not related to melatonin or placebo, and no serious adverse events were reported too (
7).
As Chojancki et al. trial have been continued up to 12 months, they could evaluate the effect of melatonin on some psychosomatic such as anxiety and intensity of depression in UC patients too. Although they have reported that melatonin 5 mg/d compared with placebo did not change anxiety or intensity of depression after 12 months. Our trial was limited to three months, so assessment of the above parameters was not possible. Moreover, it is possible that this dose (3 mg/d) is not strong enough for a positive response in all components of SF-36. In the future, we recommend doing trials by using higher doses of melatonin on clinical, biochemical, and quality of life in UC patients.
The changes in the SCCAI value in two groups over time
The changes in the Fecal calprotectin level in two groups over time
| P-value | Control group (n = 15) | Intervention group (n = 15) | Variables |
|---|
| 0.726 | 8/7 | 7/8 | Female/ Male gender (No.) |
| 0.098 | 39.60 ± 10.98 | 33.66 ± 7.72 | Age (year) |
| 0.608 | 23.39 ± 3.43 | 24.04 ± 3.40 | Body mass index |
| 0. 860 | 8.46 ± 3.41 | 8.2 ± 4.70 | Length of the disease(year) |
| 0.601 | 468.31 ± 304.48 | 401.27 ± 311.12 | Baseline Fecal calprotectin (mg/kg) |
| 0.775 | 20.33 ± 16.23 | 22.27 ± 20.30 | Baseline Erythrocyte sedimentation rate (mm/h) |
| 0.624 | 7.60 ± 8.22 | 12.53 ± 23.65 | Baseline C-reactive protein (mg/L) |
| P-value | control group (n = 15) | Intervention group (n = 15) | Variables |
|---|
| Physical function |
| 0.954 | 84 ± 17.24 | 84.33 ± 14 | Base line |
| 0.849 | 91 ± 15.27 | 90 ± 12.68 | 3 months |
| Role-physical |
| 0.906 | 60 ± 40.97 | 56.67 ± 34.68 | Base line |
| 0.967 | 75 ± 29.88 | 73.33 ± 25.82 | 3 months |
| Role-emotional |
| 0.858 | 33.34 ± 37.80 | 34.98 ± 36.76 | Base line |
| 0.050 | 51.09 ± 39.59 | 66.66 ± 35.64 | 3 months |
| Bodily pain |
| 0.619 | 66.33 ± 21.27 | 70.33 ± 22.30 | Base line |
| 0.370 | 73.67 ± 20.61 | 80.67 ± 21.43 | 3 months |
| Energy |
| 0.063 | 44.67 ± 18.75 | 55.67 ± 11.47 | Base line |
| 0.002 | 47.67 ± 16.35 | 65.33 ± 11.72 | 3 months |
| General health |
| 0.893 | 54 ± 19.10 | 53 ± 21.03 | Base line |
| 0.037 | 50.67 ± 24.12 | 70.33 ± 25.18 | 3 months |
| Health change |
| 0.806 | 65 ± 37.55 | 63.33 ± 33.89 | Base line |
| 1.000 | 70 ± 34.33 | 70 ± 30.17 | 3 months |
| Social function |
| 0.669 | 65.33 ± 33.94 | 70 ± 24.46 | Base line |
| 0.47 | 67.50 ± 31.27 | 75 ± 25 | 3 months |
| Mental health |
| 0.388 | 57.07 ± 24.45 | 64.53 ± 22.16 | Base line |
| 0.161 | 58.93 ± 25.45 | 71.47 ± 22.11 | 3 months |
| P-value | control group (n = 15) | Intervention group (n = 15) | Variables |
|---|
| 0.004 | 396.69 ± 251.95 | 119.25 ± 88.42 | Fecal calprotectin (mg/kg) |
| 0.697 | 14.86 ± 12.75 | 16.80 ± 14.58 | Erythrocyte sedimentation rate (mm/h) |
| 0.461 | 6.93 ± 11.78 | 11.86 ± 26.45 | C-reactive protein (mg/L) |