Oliver Grundmann

Irritable bowel syndrome: Epidemiology, diagnosis and treatment: An update for health-care practitioners

Irritable bowel syndrome (IBS), a chronic gastrointestinal disorder, affects from 3–20% of the US population, depending on sociocultural and comorbid factors. IBS is characterized by a symptom complex of abdominal pain and abnormal bowel habits that present as diarrhea or constipation, and general physical weakness in the absence of abnormal morphological, histological or inflammatory markers. The main diagnostic Rome III criteria as established by international professional organizations are based on exclusion criteria and the occurrence and rate of symptoms. Because the pathophysiology and causes of IBS are poorly understood, treatment approaches are mainly focused on symptom management to maintain everyday functioning and improve quality of life for persons with IBS. The mainstay of intervention is pharmacological treatment with antispasmodics and antidiarrheals for diarrhea, prokinetics and high‐fiber diets for constipation, and supportive therapy with low‐dose antidepressants to normalize gastrointestinal motility. Other interventions include lifestyle and dietary changes, psychotherapy, herbal therapies and acupuncture. The purpose of this review is to critically assess benefits and risks of current treatment approaches as well as promising complementary and alternative therapies.

Sensitivity of Salivary Glands to Radiation: from Animal Models to Therapies

Radiation therapy for head and neck cancer causes significant secondary side-effects in normal salivary glands, resulting in diminished quality of life for these individuals. Salivary glands are exquisitely sensitive to radiation and display acute and chronic responses to radiotherapy. This review will discuss clinical implications of radiosensitivity in normal salivary glands, compare animal models used to investigate radiation-induced salivary gland damage, address therapeutic advances, and project future directions in the field.

Radiation-induced salivary gland dysfunction results from p53-dependent apoptosis.

PURPOSE Radiotherapy for head-and-neck cancer causes adverse secondary side effects in the salivary glands and results in diminished quality of life for the patient. A previous in vivo study in parotid salivary glands demonstrated that targeted head-and-neck irradiation resulted in marked increases in phosphorylated p53 (serine(18)) and apoptosis, which was suppressed in transgenic mice expressing a constitutively active mutant of Akt1 (myr-Akt1). METHODS AND MATERIALS Transgenic and knockout mouse models were exposed to irradiation, and p53-mediated transcription, apoptosis, and salivary gland dysfunction were analyzed. RESULTS The proapoptotic p53 target genes PUMA and Bax were induced in parotid salivary glands of mice at early time points after therapeutic radiation. This dose-dependent induction requires expression of p53 because no radiation-induced expression of PUMA and Bax was observed in p53-/- mice. Radiation also induced apoptosis in the parotid gland in a dose-dependent manner, which was p53 dependent. Furthermore, expression of p53 was required for the acute and chronic loss of salivary function after irradiation. In contrast, apoptosis was not induced in p53-/- mice, and their salivary function was preserved after radiation exposure. CONCLUSIONS Apoptosis in the salivary glands after therapeutic head-and-neck irradiation is mediated by p53 and corresponds to salivary gland dysfunction in vivo.

Anxiolytic activity of a phytochemically characterized Passiflora incarnata extract is mediated via the GABAergic system.

The purpose of this research was to assess the anxiolytic properties of a phytochemically characterized commercial extract from Passiflora incarnata (PI; Passifloraceae) in the elevated plus maze test in mice. Using an HPLC method, the flavonoids homoorientin, orientin, vitexin, and isovitexin were identified as major compounds. Following oral administration, the extract exerted an anxiolytic effect that was comparable to diazepam (1.5 mg/kg) at a dose of 375 mg/kg and exhibited a U-shaped dose-response curve. In addition, antagonism studies using the GABA (A)/benzodiazepine receptor antagonist flumazenil and the 5-HT (1A)-receptor antagonist WAY-100 635 were conducted. The active dose was effectively antagonized by flumazenil, but not by WAY-100 635. This study is the first demonstration of the IN VIVO, GABA-mediated anxiolytic activity of an HPLC- characterized extract of Passiflora incarnata.

Kaempferol from the leaves of Apocynum venetum possesses anxiolytic activities in the elevated plus maze test in mice

The present work evaluated the anxiolytic activity of an aqueous extract of Apocynum venetum L. (Apocynaceae) and bioguided its fractionation using the elevated plus maze (EPM) in mice as a model of anxiety. A single treatment of AV extract markedly increased the percentage time spent on the open arms of the EPM in two distinct concentration ranges of 22.5-30 and 100-125 mg/kg p.o., respectively, indicating a putative anxiolytic-like activity. Fractions showing anxiolytic effects in concentrations equal to 30 or 125 mg/kg of whole extract were antagonized using the benzodiazepine antagonist flumazenil (3 mg/kg i.p.) or the 5-HT(1A) receptor antagonist WAY-100635 (0.5 mg/kg i.p.). All active fractions in a concentration equal to 125 mg/kg were effectively blocked by the benzodiazepine antagonist flumazenil, while the anxiolytic activities of fractions in the lower dose equivalent to 30 mg/kg of whole extract were inhibited by the 5-HT(1A) receptor antagonist WAY-100635. Through further separation of AV fractions it was possible to isolate and characterize the flavonol kaempferol which showed an anxiolytic-like activity in concentrations from 0.02 to 1.0 mg/kg p.o. The anxiolytic activity of kaempferol was partially antagonized by concomitant administration of flumazenil, but not by WAY-100635. In conclusion, our study clearly demonstrates that AV extract possesses anxiolytic-like activity and that at least one of its flavonoids, kaempferol, can elicit the same kind of neuropharmacological activity.

Complementary and alternative medicines in irritable bowel syndrome: An integrative view

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder with a high incidence in the general population. The diagnosis of IBS is mainly based on exclusion of other intestinal conditions through the absence of inflammatory markers and specific antigens. The current pharmacological treatment approaches available focus on reducing symptom severity while often limiting quality of life because of significant side effects. This has led to an effectiveness gap for IBS patients that seek further relief to increase their quality of life. Complementary and alternative medicines (CAM) have been associated with a higher degree of symptom management and quality of life in IBS patients. Over the past decade, a number of important clinical trials have shown that specific herbal therapies (peppermint oil and Iberogast(®)), hypnotherapy, cognitive behavior therapy, acupuncture, and yoga present with improved treatment outcomes in IBS patients. We propose an integrative approach to treating the diverse symptoms of IBS by combining the benefits of and need for pharmacotherapy with known CAM therapies to provide IBS patients with the best treatment outcome achievable. Initial steps in this direction are already being considered with an increasing number of practitioners recommending CAM therapies to their patients if pharmacotherapy alone does not alleviate symptoms sufficiently.

The pharmacology and toxicology of kratom: from traditional herb to drug of abuse.

Mitragyna speciosa (Rubiaceae), commonly known as kratom, is a tropical tree with a long history of traditional use in parts of Africa and Southeast Asia. In recent years, kratom has gained popularity for use as a recreational drug across the globe. Relatively new to the illicit market and used in a manner different from its traditional applications, preparations of kratom are touted by many as a safe and legal psychoactive product that improves mood, relieves pain, and may provide benefits in opiate addiction. Available literature was reviewed for M. speciosa via PubMed, Google Scholar, CINAHL, and EBSCO to summarize its traditional uses, phytochemical composition, pharmacology and toxicology of proposed active constituents, and potential for misuse and abuse. Research has demonstrated that both stimulant and sedative dose-dependent effects do exist, but a growing concern for the drug’s effects and safety of use has resulted in national and international attention primarily due to an increase in hospital visits and deaths in several countries that are said to have been caused by extracts of the plant. The main active alkaloid substances in kratom, mitragynine and 7-hydroxymitragynine, present with a range of CNS stimulant and depressant effects mediated primarily through monoaminergic and opioid receptors. Recently, Palm Beach County, located in the southeastern corridor of Florida, has considered regulating kratom due to public safety concerns following the death of a young adult. At the local, state, and even federal levels, governments are now being confronted with the task of determining the safety and the possible regulation of kratom extracts. There are currently no standard analytical screening techniques for mitragynine and its metabolites following ingestion limiting its detection to more sophisticated techniques like liquid chromatography-mass spectrometry to determine kratom use. The growing concern of the abuse potential of kratom requires careful evaluation of its benefits and potential toxicities.

Menthol--pharmacology of an important naturally medicinal "cool".

Menthol, a natural product of the peppermint plant Mentha x piperita (Lamiaceae), is a monoterpene which is widely used as a natural product in cosmetics, a flavoring agent, and as an intermediate in the production of other compounds. Various extracts from peppermint contain menthol as a major active constituent and have been used for centuries as traditional medicines for a number of ailments including infections, insomnia, and irritable bowel syndrome as well as an insect repellent. Menthols characteristic cooling sensation is due, in part, to the activation of sensory neurons generally termed transient receptor potential (TRP) channels, in particular transient receptor potential melastatin family member 8 (TRPM8) and transient receptor potential subfamily A, member 1 (TRPA1). Menthol acts upon TRPM8 receptors by rapidly increasing intracellular calcium and mobilizing calcium flux through the channels to induce cold response signals at the application site. Aside from its cold-inducing sensation capabilities, menthol exhibits cytotoxic effects in cancer cells, induces reduction in malignant cell growth, and engages in synergistic excitation of GABA receptors and sodium ion channels resulting in analgesia. Notwithstanding its plethora of benefits, menthols coldsensitivity response mechanism has been shown to inhibit mucosal recognition of nicotine and cigarette toxins common in mentholated cigarette brands thus potentially leading to toxic effects. Menthol may prove a valuable lead structure for the synthesis of drugs that target multiple receptors involved with a number of pharmacological effects.

Mechanism of St. John's wort extract (STW3-VI) during chronic restraint stress is mediated by the interrelationship of the immune, oxidative defense, and neuroendocrine system.

Chronic stress is a contributing risk factor for the development of psychiatric illnesses such as anxiety and depression disorders. The aim of the present study was to evaluate the mechanisms of action of the standardized St. Johns wort extract (STW3-VI; SJW) in a chronic restraint stress model. Markers of antioxidant capacity such as superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) in the hippocampus and hypothalamus, and plasma levels of ACTH and corticosterone as well as the inflammatory markers IL-6 and TNF-alpha were determined in rats exposed to chronic restraint stress for 21 consecutive days. In addition, total body and relative organ weights as well as behavioral changes in the open field test were evaluated on the last day. The results show that stressed animals decreased in open field activity compared to unstressed animals, which could be reversed by fluoxetine (10mg/kg, p.o.) and SJW (125-750mg/kg, p.o.) treatment. In addition, chronic restraint stress significantly decreased thymus and spleen indices in the stressed control group. However, treating stressed rats with fluoxetine or STW3-VI produced a significant and dose dependent increase in both thymus and spleen indices compared to stressed controls. Additionally, SJW and fluoxetine significantly reduced stress-induced increases in plasma ACTH and corticosterone levels. Furthermore, the administration of SJW significantly reduced the stress-induced increase in TNF-alpha levels. Our data provide new evidence for the hypothesis that the mechanism of action of STW3-VI is mediated by the interrelationship between the immune, oxidative defense and neuroendocrine system.

The value of bioelectrical impedance analysis and phase angle in the evaluation of malnutrition and quality of life in cancer patients—a comprehensive review

Bioelectrical impedance analysis (BIA) and especially its derived parameter phase angle have been widely used in different populations. The variability of BIA measures has often been cited as a major limitation for its clinical use in evaluating nutritional status and overall health of patients. Cancer patients often present with malnourishment and cachexia, which complicate the course of treatment and affect outcomes. PubMed, CINAHL, EBSCO and Cochrane Library have been searched for relevant publications in English for BIA in cancer patients. Out of 197 total results, 27 original research articles related to BIA measures in cancer patients were included in this review. Studies indicate that the use of BIA and phase angle measures can benefit in the clinical management of cancer patients in multiple ways: in the prevention; diagnosis; prognosis; and outcomes related to treatments that affect nutritional and overall health status. Phase angle and fat-free mass measures were most commonly evaluated and correlated with nutritional status and survival rate. One limitation of BIA measures is the high interpatient variability which requires careful interpretation of results in the context of the individual patient rather than comparison with population data. The BIA and phase angle provide practitioners for the evaluation of nutritional and overall health status in cancer patients with a convenient and non-invasive technique and should be encouraged.