Continuous subcutaneous administration of high-dose salmon calcitonin in bone metastasis: pain control and beta-endorphin plasma levels

The effects of salmon calcitonin on epileptic seizures, epileptogenesis, and postseizure hippocampal neuronal damage in pentylenetetrazole-induced epilepsy model in rats

Epilepsy is one of the most common neurological disorders that severely affect the life quality of many people worldwide. Excitatory-inhibitory mechanisms, oxidative stress, and also inflammation systems have been implicated in the pathogenesis of epilepsy. Recent studies have shown that salmon calcitonin (sCT) has positive effects on the nervous system. However, its relation with epilepsy is still unclear. This study aimed to investigate the effect of sCT on epileptic seizures, epileptogenesis, and postseizure hippocampal neuronal damage in pentylenetetrazole (PTZ)-induced epilepsy model in rats. The study was performed in two steps. In the first step, the effect of sCT on epileptic seizures was evaluated by using electroencephalography (EEG) in fully kindled rats. In the second step, the effect of sCT on epileptogenesis was evaluated by using the kindling process. Glutamate and gamma-aminobutyric acid (GABA), thiobarbituric acid reactive substance (TBARS), superoxide dismutase (SOD), catalase (CAT), tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1 β), and interleukin 6 (IL-6) were measured in the second group in the brain and serum. Hippocampal regions were stained with hematoxylin-eosin and toluidine blue to evaluate hippocampal neuronal damage histopathologically. Salmon calcitonin showed an antiepileptic effect in fully kindled rats and also prevented the development of epileptogenesis in the kindling process. Besides, sCT decreased glutamate and increased GABA levels. Furthermore, it reduced TBARS levels and increased SOD and CAT levels. On the other hand, it decreased TNF-α levels, IL-1 β levels, and IL-6 levels. Histopathologically, sCT decreased neuronal damage in all hippocampal regions. Our findings are the first preclinical report to show the positive effect of sCT on epileptic seizures and epileptogenesis. Further investigation is required to answer the questions raised about the probable mechanisms involved.

A Randomized Placebo-Controlled Trial Evaluating the Analgesic Effect of Salmon Calcitonin in Refractory Bone Metastasis Pain

Injection calcitonin is a natural hormone inhibiting osteoclastic bone resorption have been used as an analgesic to control bone metastasis pain or pain due to osteoporosis or fracture. This randomized double blind placebo controlled trial was undertaken to determine the role of injection Salmon Calcitonin therapy to control refractory pain caused due to bone metastasis arising from cancer breast, lung, prostate or kidney. All patients had received palliative radiotherapy and were suffering unsatisfactory pain relief on NSAIDs and tab morphine. Fourteen days inj. calcitonin or placebo injections were administered in 23 patients initially as high dose induction dose (800 IU per day SC) followed 200 IU subcutaneous (SC) once a day. Patients were assessed for pain intensity and quality of life on EORTC QLQ-30 questionnaire 6 hourly for 2 days and on 7^th and 30^th day. Any incidence of hypercalcemia, bone fracture, nerve root and bone marrow compression were also noted. This study found a significant reduction in pain after SC calcitonin injection therapy at 14 and 30 days' assessment. No patients in the study group required rescue analgesia after 18 hrs. There was a statistically significant difference in rescue analgesics required between the groups during two days hospitalization. Global health as well as physical and social wellbeing was better at 30 and 90 days in the study group as compared to control group, however it could not reach a statistical significance which may be attributed to the small sample size of the study.

Analgesic effects of calcitonin on radicular pain in male rats

Purpose

Radicular pain is a frequently observed symptom of lumbar disk herniation or lumbar spinal canal stenosis. Achieving radicular pain relief is difficult. This type of pain may progress to chronic neuropathic pain. Calcitonin (elcatonin [eCT]) has been used mainly for hypercalcemia and pain associated with osteoporosis. The purpose of this study was to investigate analgesic effects of repeated eCT administration on radicular pain in male rats and changes in mRNA-expression levels of voltage-dependent sodium channels in the dorsal root ganglion (DRG).

Methods

Seventy male Sprague-Dawley rats were used. A right L5 hemilaminectomy and an L5-L6 partial facetectomy were performed to expose the right L5 nerve root. Under a microscope, the right L5 spinal nerve root was tightly ligated extradurally with 8-0 nylon suture proximally to the DRG to cause radicular pain in rats. Mechanical hyperalgesia, thermal hyperalgesia, and analgesic effects of eCT were compared among rats with radicular pain that received eCT, those that received the vehicle, and sham rats that received the vehicle. Real-time reverse-transcription PCR was performed to measure mRNA-expression levels of tetrodotoxin-sensitive (Na_V1.3 and Na_V1.6) and tetrodotoxin-resistant (Na_V1.8 and Na_V1.9) sodium channels in the DRG.

Results

Mechanical and thermal hyperalgesic reactions occurring in rats with radicular pain significantly improved on days 5 and 9 of eCT administration, respectively. In rats with radicular pain, mRNA-expression levels of Na_V1.3, Na_V1.8, and Na_V1.9 increased. After repeated eCT administration, mRNA-expression levels of these sodium channels in rats with radicular pain improved to the same levels as in sham rats.

Conclusion

The present study demonstrated that repeated systemic eCT administration was effective for radicular pain. No serious side effects of eCT have been reported thus far. Therefore, calcitonin may be a preferred therapeutic option for patients with radicular pain or for those requiring long-term treatment.

Effect of Intranasal Calcitonin in a Patient with McCune-Albright Syndrome, Fibrous Dysplasia, and Refractory Bone Pain

McCune-Albright syndrome (MAS) is a rare disease defined by the triad of polyostotic fibrous dysplasia of bone, café-au-lait skin spots, and precocious puberty. No available treatment is effective in changing the course of fibrous dysplasia of bone, but symptomatic patients require therapeutic support to reduce bone pain and prevent fractures and deformities. We report the case of a 27-year-old woman with MAS and severe fibrous dysplasia. She was diagnosed with MAS at 4 years of age and, during follow-up, she had multiple pathological fractures and bone pain refractory to treatment with bisphosphonates, tricyclic antidepressants, and opioids. The pain was incapacitating and the patient required a wheelchair. Intranasal calcitonin was then started, and, 30 days later, the patient already showed significant improvement in pain severity at the affected sites. After 3 months, she was able to walk without assistance. No adverse effects were observed, nor were any significant changes in serum levels of calcium, phosphorus, and alkaline phosphatase. Calcitonin has a well-recognized analgesic effect on bone tissue. Despite the small number of studies involving patients with MAS, calcitonin may be considered a short-term therapeutic option in cases of severe and refractory bone pain.

Pain Management in Elderly Patients

In elderly patients, persistent pain negatively impacts quality of life. An interdisciplinary approach to pain management and emphasis on quality improvement will help to achieve better therapeutic outcomes. Managing pain in the geriatric population is challenging because of age-related changes in pain perception, cognition, pharmacokinetics, and drug effects. Improvement and maintenance of physical and emotional function is the goal. Pharmacotherapy should be initiated conservatively and titrated to effective doses with minimal adverse effects. Milder pain should be treated with non-opioid analgesics with a progression toward opioids and/or adjuvant medications as the pain intensifies. Acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, and adjuvant medications represent most of the analgesic agents used in pain management. Knowing the underlying mechanism of pain will help guide pharmacologic therapy. The patient should be monitored initially, with every dose change, and periodically to assess efficacy and severity of adverse effects.

Intravenous flurbiprofen axetil enhances analgesic effect of opioids in patients with refractory cancer pain by increasing plasma β-endorphin

BACKGROUND

The study aimed to investigate the analgesic effect of a combination of intravenous flurbiprofen axetil and opioids, and evaluate the relationship between refractory pain relief and plasma β-endorphin levels in cancer patients.

MATERIALS AND METHODS

A total of 120 cancer patients was randomly divided into two groups, 60 patients took orally morphine sulfate sustained-release tablets in group A, and another 60 patients receiving the combination treatment of intravenous flurbiprofen axetil and opioid drugs in group B. After 7 days, pain relief, quality of life improvement and side effects were evaluated. Furthermore, plasma β-endorphin levels were measured by radioimmunoassay.

RESULTS

With the combination treatment of intravenous intravenous flurbiprofen axetil and opioids, the total effective rate of pain relief rose to 91.4%, as compared to 82.1% when morphine sulfate sustained-release tablet was used alone. Compared with that of group A, the analgesic effect increased in group B (p=0.031). Moreover, satisfactory pain relief was associated with a significant increase in plasma β-endorphin levels. After the treatment, plasma β-endorphin level in group B was 62.4±13.5 pg/ml, which was higher than that in group A (45.8±11.2 pg/ml) (p<0.05).

CONCLUSIONS

Our results suggest the combination of intravenous flurbiprofen axetil and opioids can enhance the analgesic effect of opioid drugs by increasing plasma β-endorphin levels, which would offer a selected and reliable strategy for refractory cancer pain treatment.

Subcutaneous fluid and drug delivery: safe, efficient and inexpensive

Patients with difficult venous access or oral intolerance and clinical situations with inadequate response to oral therapy have generated the need for alternative routes of delivery for drugs and fluids.

The purpose of this study was to conduct a systematic review examining the evidence for subcutaneous (SC) administration of drugs and/or fluids.

We used a broad search strategy using electronic databases CINAHL, EMBASE, PubMed and Cochrane library, key terms and ‘Medical Subject Headings’ (MeSH) such as ‘subcutaneous route’, ‘hypodermoclysis’ and the name/group of the most used drugs via this route (e.g. ‘ketorolac, morphine, ceftriaxone’, ‘analgesics, opioids, antibiotics’).

We conclude that the SC route is an effective alternative for rehydration in patients with mild–moderate dehydration and offers a number of potential advantages in appropriately selected scenarios. Experience of administering drugs by this route suggests that it is well tolerated and is associated with minimal side-effects.

Demethylating drugs as novel analgesics for cancer pain

PURPOSE

In this study, we evaluated the analgesic potential of demethylating drugs on oral cancer pain. Although demethylating drugs could affect expression of many genes, we focused on the mu-opioid receptor (OPRM1) gene pathway, because of its role in pain processing. We determined the antinociceptive effect of OPRM1 re-expression in a mouse oral cancer model.

EXPERIMENTAL DESIGN

Using a mouse oral cancer model, we determined whether demethylating drugs produced antinociception through re-expression of OPRM1. We then re-expressed OPRM1 with adenoviral transduction and determined if, and by what mechanism, OPRM1 re-expression produced antinociception. To determine the clinical significance of OPRM1 on cancer pain, we quantified OPRM1 methylation in painful cancer tissues and nonpainful contralateral normal tissues of patients with oral cancer, and nonpainful dysplastic tissues of patients with oral dysplasia.

RESULTS

We demonstrated that OPRM1 was methylated in cancer tissue, but not normal tissue, of patients with oral cancer, and not in dysplastic tissues from patients with oral dysplasia. Treatment with demethylating drugs resulted in mechanical and thermal antinociception in the mouse cancer model. This behavioral change correlated with OPRM1 re-expression in the cancer and associated neurons. Similarly, adenoviral-mediated OPRM1 re-expression on cancer cells resulted in naloxone-reversible antinociception. OPRM1 re-expression on oral cancer cells in vitro increased β-endorphin secretion from the cancer, and decreased activation of neurons that were treated with cancer supernatant.

CONCLUSION

Our study establishes the regulatory role of methylation in cancer pain. OPRM1 re-expression in cancer cells produces antinociception through cancer-mediated endogenous opioid secretion. Demethylating drugs have an analgesic effect that involves OPRM1.

Combined analysis of circulating β-endorphin with gene polymorphisms in OPRM1, CACNAD2 and ABCB1 reveals correlation with pain, opioid sensitivity and opioid-related side effects

Background

Opioids are associated with wide inter-individual variability in the analgesic response and a narrow therapeutic index. This may be partly explained by the presence of single nucleotide polymorphisms (SNPs) in genes encoding molecular entities involved in opioid metabolism and receptor activation. This paper describes the investigation of SNPs in three genes that have a functional impact on the opioid response: OPRM1, which codes for the μ-opioid receptor; ABCB1 for the ATP-binding cassette B1 transporter enzyme; and the calcium channel complex subunit CACNA2D2. The genotyping was combined with an analysis of plasma levels of the opioid peptide β-endorphin in 80 well-defined patients with chronic low back pain scheduled for spinal fusion surgery, and with differential sensitivity to the opioid analgesic remifentanil. This patient group was compared with 56 healthy controls.

Results

The plasma β-endorphin levels were significantly higher in controls than in pain patients.

A higher incidence of opioid-related side effects and sex differences was found in patients with the minor allele of the ABCB1 gene. Further, a correlation between increased opioid sensitivity and the major CACNA2D2 allele was confirmed. A tendency of a relationship between opioid sensitivity and the minor allele of OPRM1 was also found.

Conclusions

Although the sample cohort in this study was limited to 80 patients it appears that it was possible to observe significant correlations between polymorphism in relevant genes and various items related to pain sensitivity and opioid response. Of particular interest is the new finding of a correlation between increased opioid sensitivity and the major CACNA2D2 allele. These observations may open for improved strategies in the clinical treatment of chronic pain with opioids.

The effect of calcitonin on β-endorphin levels in postmenopausal osteoporotic patients with back pain

The purpose of this study was to evaluate the efficacy of calcitonin on beta-endorphin levels in female patients experiencing back pain associated with postmenopausal osteoporosis. The secondary purpose was to assess the pain and quality of life in these patients. There were 30 patients with a mean age of 58.2+/-5.4 years in the treatment group and 26 patients with a mean age of 58.8+/-5.2 years in the placebo group in this randomized, placebo-controlled study. The patients subcutaneously received 100 IU salmon calcitonin or placebo injections and 1,000 mg elementary calcium for 2 weeks. Baseline plasma beta-endorphin levels were measured and repeated after 2 weeks. Patients' pain and quality of life (QOL) were evaluated by using the Visual Analogue Scale, Modified Face Scale, Beck Depression Index, and Nottingham Health Profile. Patients' global assessment of disease activity was also performed at baseline and at the end of the first and second week. We found that plasma beta-endorphin levels in the treatment group were significantly higher than the placebo group at the end of the second week (p<0.001). Although pain and QOL scores were improved at the end of the second week in both groups (p<0.05), the improvement in the treatment group was more significant when compared with the placebo group (p<0.05). Therefore, calcitonin is an analgesic agent, as it increases the plasma beta-endorphin levels in patients with postmenopausal osteoporosis, which consequently improves QOL.

The effectiveness of calcitonin on chronic back pain and daily activities in postmenopausal women with osteoporosis

The aim of this study was to investigate the effect of nasal calcitonin on chronic back pain and disability attributed to osteoporosis. The study design involved three groups of osteoporotic postmenopausal women suffering from chronic back pain. Group I consisted of 40 women with vertebral fractures, group II of 30 women with degenerative disorders and group III of 40 patients with non specific chronic back pain and without abnormality on plain X-rays. Pain intensity was measured using a numerical rating scale (NRS) and disability due to back pain was measured using the Oswestry disability questionnaire. The patients were randomly assigned to receive, for three months, either 200 IU intranasal salmon calcitonin and 1,000 mg of oral calcium daily (groups IA, IIA, IIIA) or 1,000 mg of oral calcium daily (groups IB, IIB, IIIB). Repeated measures ANOVA showed that there were no significant time, group or interaction effects for pain intensity and disability in any of the groups studied. Mean Oswestry and NRS scores were reduced during the follow-up period in the groups IA, IIIA, but the differences between the two time points were not statistically significant. Intranasal calcitonin has no effect on chronic back pain intensity and functional capacity of osteoporotic women regardless of the presence of fractures, degenerative disorders or chronic back pain of non-specific etiology.

Continuous Subcutaneous Infusion of Opiates at End-of-Life

OBJECTIVE:

To review pertinent controlled trials using the continuous subcutaneous infusion of opioids (CSIO) at end-of-life and offer insight to pharmacists and clinicians into the appropriate use of this route of administration.

DATA SOURCES:

A MEDLINE search for information regarding the subcutaneous administration of opioids in terminally ill patients (1975-December 2002) was conducted using the key words subcutaneous, narcotics, morphine, hydromorphone, fentanyl, pain, hospices, and palliative care. Additional references were located through review of bibliographies of the articles cited. Case reports and postsurgical studies were excluded. Searches were limited to English-language studies using humans.

STUDY SELECTION AND DATA EXTRACTION:

Experimental and observational studies were evaluated, using prospective trials as the evidence base for conclusions and including pertinent retrospective trials as they relate to the subcutaneous infusion of opioids at end-of-life.

DATA SYNTHESIS:

CSIO is effective and safe for use in terminal illness. Appropriate situations for consideration of CSIO are when difficulties arise in using the oral route, standard oral opiate therapy has failed adequate trials, the patient has limited intravenous access, adequate supervision of the CSIO is present, and CSIO will not unduly limit the functional activity of the patient.

CONCLUSIONS:

CSIO has a proven role in the management of pain at end-of-life. CSIO should not be considered the first route for administration of opiates, but does offer distinct advantages in the appropriate setting. CSIO continues to be a choice for end-of-life patients and is gradually becoming a standard practice in palliative medicine.

Calcitonin for metastatic bone pain

BACKGROUND

Pain is the most frequent symptom experienced by cancer patients, its intensity dependent on the site of the tumour. Tumours that compromise bone or nervous structures due to the bone destruction process are the most painful. There are several treatments to deal with pain (and other symptoms) caused by bone metastasis. The hormone, calcitonin, has the potential to relieve pain, and also retain bone density, thus reducing the risk of fractures.

OBJECTIVES

To assess the effectiveness of calcitonin in controlling metastatic bone pain and reducing bone complications (hypercalcemia, fractures and nervous compression) in patients with bone metastases.

SEARCH STRATEGY

Electronic searches were performed in MEDLINE (1966-2001), EMBASE (1974-2001), the Cochrane Central Register of Controlled Trials (Issue 2, 2001), specialised registers of the Cochrane Cancer Network and of the Cochrane Pain, Palliative and Supportive Care Group. Registers of clinical trials in progress were also searched.

SELECTION CRITERIA

Studies were included if they were randomised, double-blind clinical trials of patients with metastatic bone pain, treated with calcitonin, where the major outcome measure was pain, assessed at four weeks or longer.

DATA COLLECTION AND ANALYSIS

Study selection and data extraction were performed by two independent reviewers. Only two studies (90 patients) were eligible for inclusion in the review and therefore meta-analysis of the data was not possible. Intention-to-treat analysis was performed by imputing all missing values as adverse outcomes.

MAIN RESULTS

Of the two small studies included in the review, one study showed a non-significant effect of calcitonin in the number of patients with total pain reduction (RR 2.50; CI 95%, 0.55 to 11.41). The second study provided no evidence that calcitonin reduced analgesia consumption (RR 1.05; CI 95%, 0.90 to 1.21) in patients with painful bone metastases. There was no evidence that calcitonin was effective in controlling complications due to bone metastases; for improving quality of life; or patients' survival. Although not statistically significant, a greater number of adverse effects were observed in the groups given calcitonin in the two included studies (RR 3.35, CI 95%, 0.72 to 15.66).

REVIEWER'S CONCLUSIONS

The limited evidence currently available for systematic review does not support the use of calcitonin to control pain from bone metastases. Until new studies provide additional information on this treatment, other therapeutic approaches should be considered.

Malignant bone pain: pathophysiology and treatments

Metastatic involvement of the bone is one of the most frequent causes of pain in cancer patients and represents one of the first signs of widespread neoplastic disease. The pain may originate directly from the bone, from nerve root compression, or from muscle spasms in the area of the lesions. The mechanism of metastatic bone pain is mainly somatic (nociceptive), even though, in some cases, neuropathic and visceral stimulations may overlap. The conventional symptomatic treatment of metastatic bone pain requires the use of multidisciplinary therapies, such as radiotherapy, in association with systemic treatment (hormonotherapy, chemotherapy, radioisotopes) with the support of analgesic therapy. Recently, studies have indicated the use of bisphosphonates in the treatment of pain and in the prevention of skeletal complications in patients with metastatic bone disease. In some patients, pharmacologic treatment, radiotherapy, and radioisotopes administered alone or in association are not able to manage pain adequately. The role of neuroinvasive techniques in treating metastatic bone pain is debated. The clinical conditions of the patient, his life expectancy, and quality of life must guide the physician in the choice of the best possible therapy.