Serotonin receptor 2A blocker (risperidone) has no effect on human polyomavirus JC infection of primary human fetal glial cells

A recent report demonstrated that JC virus (JCV) employs serotonin receptor 2A (5HT(2A)R) to infect the glial cells. To assess the ability of a potent 5HT(2A)R blocker, risperidone, to inhibit JCV infection, the authors treated primary human fetal glial (PHFG) cells in vitro with risperidone for 24 h and inoculated with JCV(Mad1). There was no significant difference in JCV genome copies or mRNA transcripts and protein expression in treatment-naive and risperidone-treated PHFG cells. These data indicate that risperidone does not inhibit JCV(Mad1) attachment, internalisation, and replication in PHFG cells, and 5HT(2A)R blockers may not be effective in treating progressive multifocal leukoencephalopathy (PML).

Ritonavir and disulfiram have potential to inhibit caspase-1 mediated inflammation and reduce neurological sequelae after minor blast exposure

Caspase-1 triggers cytokine release following acceleration-induced concussive head injury. Minor blast injury in which no physical tissue injury occurs, results in the release of cytokines in a similar fashion. Ritonavir, a generically available protease inhibitor with a benign short-term side-effect profile, has been shown to inhibit expression of caspase-1. We review the relevant literature and propose that ritonavir may be of benefit in reducing adverse neuropsychiatric outcomes and hastening recovery following mild blast injury. Further research in animal models of blast injury followed by clinical studies would determine whether this therapy is effective.

Cancer chemotherapy and cachexia: mirtazapine and olanzapine are 5-HT3 antagonists with good antinausea effects

Mirtazapine and olanzapine are easy-to-use psychiatric drugs with potent antinausea effects. Ondansetron and later members of the 'setron class are currently standard treatments for cancer chemotherapy-related nausea and emesis. They are potent 5-HT3 blockers, but it is often not appreciated that mirtazapine and olanzapine bind with similar affinity to 5-HT3 receptors, have a longer half-life, are considerably cheaper than the 'setron class, and often offer better and smoother 24-h nausea control than 'setron class drugs. Mirtazapine and olanzapine often have salutary antianxiety effects and improve sleep quality. They occasionally relieve chemotherapy-related and advanced cancer-related nausea and appetite decrease better than the 'setron group that are specifically marketed for nausea control. Mirtazapine and olanzapine frequently give potent nausea reduction and appetite increase in advanced cancer-related cachexia. Several cytokine changes potentially induced by mirtazapine and olanzapine use are discussed that may have salutary effects in several cancers. We suggest mirtazapine and olanzapine be included as first-line options in treating both chemotherapy- and advanced cancer-related nausea. Multiple clinical and economic advantages of mirtazapine and olanzapine over currently used 'setron class medicines are reviewed. Double-blind studies against the 'setron class drugs are warranted.

How lithium treatment generates neutrophilia by enhancing phosphorylation of GSK-3, increasing HIF-1 levels and how this path is important during engraftment

Lithium is commonly used in psychiatry for mood stabilization. Lithium treatment results in neutrophilia, increased platelets and increased circulating CD34+ haematopoietic stem cells, HSC. This paper outlines the newly discovered mechanism by which this occurs. Glycogen synthase kinase-3, GSK-3, phosphorylates and thereby inactivates hypoxia-induced factor-1, HIF-1. HIF-1 is a transcription factor triggering transcription of multiple genes related to adaptation to hypoxia, among which is CXCL12. CXCL12 forms the primary homing gradient for CD34+ HSCs towards the hypoxic, trophic bone marrow niche to which they must go to thrive. Lithium inhibits GSK-3 thereby increasing active HIF-1 that results in a stronger CXCL12 homing gradient. Trophic niche function is enhanced, ultimately resulting in increased production of neutrophils, platelets and CD34+ cells. Sitagliptin is a new drug to treat diabetes that coincidentally inhibits destruction of CXCL12. Thus, lithium and sitagliptin enhance CXCL12 by different paths, potentially increasing trophic niche function. Awareness of this path is important in HSC transplantation.

Melanoma inhibition by cyclooxygenase inhibitors: role of interleukin-6 suppression, a putative mechanism of action, and clinical implications

Melanoma progression is often associated with supranormal levels of interleukin-6 (IL-6). Il-6 is an important growth factor for many cases of melanoma. A recent case report by Lejeune et al. [Melanoma Res 2006;16:263-265] of remission of an advanced melanoma during treatment with the cyclooxygenase, (COX) inhibitor rofecoxib can be explained by rofcoxib-mediated lowering of tumor-produced Il-6. Several examples of rofecoxib's ability to lower Il-6 in humans have been published recently in other settings, and many reports indicate that other commonly used COX inhibitors like aspirin, diclofenac, etodolac, indomethacin, naproxen, and many others, also lower Il-6 in humans. These studies are reviewed. The likely mechanism of COX inhibition leading to Il-6 lowering is due to the tendency for Il-6 levels to be controlled by intracellular cyclic adenosine monophosphate (cAMP). Adenylate cyclase is the rate-limiting enzyme in cAMP synthesis. Because adenylate cyclase activity is allosterically enhanced when it binds prostaglandin E, the latter increases Il-6. COX inhibition lowers prostaglandin E levels. This lowers intracellular cAMP levels. Lower cAMP results in lower Il-6 synthesis, lower levels of a required growth factor. Controlled studies are needed to define the role of COX inhibitors in melanoma treatment.

Doxorubicin cardiomyopathy via TLR-2 stimulation: potential for prevention using current anti-retroviral inhibitors such as ritonavir and nelfinavir

Doxorubicin remains a useful anti-cancer drug but as lifetime dose approaches 500 mg/m2 and particularly when this dose is exceeded, iatrogenic life-threatening cardiomyopathy becomes progressively more likely. This note reviews evidence indicating that doxorubicin induced cardiomyopathy is partly mediated by stimulation of Toll-like receptors (TLR) 2 and 4 which are expressed on cardiomyocytes. Indinavir, nelfinavir, ritonavir, and saquinavir are currently marketed protease inhibitors used to suppress human immunodeficiency virus. They have recently been shown to inhibit signalling at TLR 2 and 4 as well as intracellular events downstream from these receptors. It is possible that these FDA-approved anti-retroviral protease inhibitors could be used off-label to diminish likelihood of doxorubicin cardiotoxicity permitting higher doxorubicin doses. We suggest that currently marketed anti-viral protease inhibitors be investigated in animal models of doxorubicin cardiomyopathy and if such studies do indeed show protection, human studies be initiated.

Consideration of use of phenothiazines in particular trifluorperazine for epidermal growth factor receptor associated cancers

Papers from a generation ago suggested that phenothiazines--in particular trifluorperazine (Stelazine) a medicinal approved by the FDA and still commonly used for schizophrenia--downregulate the epidermal growth factor receptor. As numerous cancers--e.g., colon cancer, breast cancer, pancreatic cancer and glioblastoma--are dependent on signaling via this receptor, we here suggest that phenothiazines such as trifluorperazine be considered for use in epidermal growth factor receptor associated cancers.

Consideration of acamprosate for treatment of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal disease of degeneration of motor neurons. There is no known cure or life extending treatment. Much recent work has suggested that a possible cause of ALS is constitutive opening of the calcium pore in glutamate sensitive AMPA channels secondary to a failure of RNA editing that would change a crucial glutamate in the channel to arginine. Here, we point out that the small molecule pharmaceutical acamprosate, usually used as a drug to maintain alcohol abstinence, may block this calcium pore--as do the related molecules endogenous polyamines such as putrescine, cadaverine, spermidine and spermine--and thus might have use in ALS.

Aspirin, TNF-alpha, NFkB, and survival in multiple myeloma: the importance of measuring TNF-alpha

Aspirin and other cyclooxygenase inhibitors can increase levels of tumor necrosis factor-alpha and engage pro-apoptosis paths and/or anti-apoptosis paths. Seemingly conflicting data are briefly reviewed. Aspirin has been shown to slightly increase survival duration in multiple myeloma. In this brief note caution is raised about use of aspirin and COX inhibitors generally in inflammatory states and specifically in myeloma. Should they increase tumor necrosis factor-alpha they could exacerbate disease. A figure is presented showing the tendency for interleukin-6 and tumor necrosis factor-alpha, both demonstrated to be growth factors in myeloma, to be counter-regulated. Since both are now easily measured by specialty labs, it would be reasonable to monitor these during myeloma treatment generally, and particularly when using aspirin, COX inhibitors, or any other drug with potential to increase these growth factors.

Some fibrocystic breast change may be caused by sexually transmitted H. pylori during oral nipple contact: supporting literature and case report of resolution after gut H. pylori eradication treatment

OBJECTIVES

To briefly review previously published evidence for Helicobacter pylori (Hp), colonization of extra-intestinal sites and suggest an hypothesis that breast acini and ducts be added to this list, concluding such breast colonization is not rare and is a sexually transmitted infection.

METHODS

PubMed literature search and review with a case report.

CONCLUSIONS

(1) Evidence indicates oral Hp is common and can remain in the mouth after successful eradication in stomach and duodenum. (2) Evidence indicates that the breast is also occasionally colonized by Hp. (3) Hp may be injected retrograde up into ducts of the breast during oral nipple stimulation during sexual activity and this Hp may give rise to some cases of fibrocystic breast change. (4) A case of painful fibrocystic change that had been present for two years in a 27 year old female, resolved after gastrointestinal Hp treatment.

How influenza's neuraminidase promotes virulence and creates localized lung mucosa immunodeficiency

Neuraminidase (NA) is an enzyme coded for by the genome of influenza critical for its pathogenicity and survival. Three currently accepted roles for this NA in promoting influenza virulence are: 1. NA cleaves newly formed virus particles from the host cell membrane. Without NA, newly formed virus would remain attached to the cell within which it was produced. 2. NA prevents newly released virus particles from aggregating to each other, preventing clumping that would reduce dissemination. 3. NA promotes viral penetration of sialic acid-rich mucin that bathes and protects respiratory epithelium through which the virus must spread and replicate. We outline here previous research evidence of two further, albeit hypothetical, functions of NA that together could cause disruption the mucosa-IgA axis, creating localized partial immunosuppressed state, enhancing both influenza infection itself and secondary bacterial pneumonia: 4. IgA provides primary immunoglobulin defense of mucosal surfaces. The hinge region of IgA is normally sialylated. IgA denuded of sialic acid is recognized, bound, and cleared by hepatic asialoglycoprotein receptor (ASGPR). Thus, IgA exposed to free NA would be so denuded and have increased hepatic clearance. 5. NA removes sialic acid moieties from mucosa-residing gamma/delta T cells or IgA producing B cells. Previous work indicates desialylation of these lymphocytes' outer cell membrane results in altered homing, to bone marrow, away from mucosa. Currently marketed NA inhibitors oseltamivir (Tamiflu) and zanamivir (Relenza) are FDA approved in USA for influenza prophylaxis and treatment. These NA inhibitors lower incidence of secondary bacterial infection in cases where an influenza infection occurs despite their use. Moreover, they are ameliorative in patients with secondary bacterial infections treated with antibiotics, a benefit that surpasses the treatment of antibiotics alone. We interpret these last two points as indicating our ascription of localized immunosuppression to influenza's NA could be correct and lead to new treatments of infections generally.

Co-administration of ramelton and fluvoxamine to increase levels of interleukin-2

Ramelton is a medication recently approved by the FDA for treatment of insomnia. Ramelton is an analogue of melatonin with a higher affinity even than that of the natural ligand. Clinically this potentially strong effect of the ligand is blunted by the fact that upon oral ingestion there is first pass metabolism of greater than 95%. This liver metabolism is mediated by the CYP1A2 enzyme. It turns out that the medication fluvoxamine approved by the FDA for the treatment of obsessive compulsive disorder is a potent inhibitor of the CYP1A2 enzyme, with the effect that co-administration of ramelton and fluvoxamine increases blood levels of ramelton by 100-200 fold. It turns out that lymphocytes bear the melatnonin receptors and stimulation of these receptors on lymphocytes cause the lymphocytes to elaborate the pro-inflammatory cytokine interleukin-2 (Il-2). Thus, here we point out that co-administration of ramelton and modest doses of fluvoxamine may be able to smoothly produce increased levels of Il-2, this may be useful in diseases and conditions such as metastatic cancer and maintenance of suppression of the HIV virus.

Review of evidence that posttransplantation psychiatric treatment commonly affects prolactin levels and thereby influences graft fate

Delirium, depression and other psychiatric difficulties are commonly encountered by posttransplantation patients, and antipsychotic medicines are frequently used to treat these difficulties. This article reviews previous research data concerning the immunological effects of these medicines, with particular focus on the consequences of prolactin elevation. Unproven but of concern is that these effects may influence graft fate. Older antipsychotic medicines such as haloperidol and chlorpromazine have a high likelihood of elevating prolactin. Prolactin is an immunologically active molecule generally promoting bone marrow function. This may be of benefit post-stem-cell transplant, helping engraftment, but could further rejection of solid-organ transplants. Elevated prolactin is implicated in the facilitation of graft-versus-host disease. Aripiprazole is the antipsychotic medicine least likely to increase prolactin (and may actually decrease prolactin); risperidone, the most likely to increase prolactin. Olanzapine, quetiapine and ziprazadone are antipsychotic medicines with a lower likelihood of elevating prolactin. Older ("neuroleptic") antipsychotics, such as chlorpromazine, droperidol and haloperidol, perphenazine and many others, are likely to elevate serum prolactin. Among antidepressants, most serotonin reuptake inhibitors, with the exception of sertraline, can slightly elevate prolactin. The atypical (i.e., alone in their class) antidepressants bupropion and mirtazapine are prolactin neutral. The immunological consequences of psychiatric medicines should be considered when treating transplant patients for delirium, depression and thought disorders; in addition, if elevation of prolactin is thought to be of immunological importance during psychiatric treatment, then it should be monitored and treated. The dopamine agonists used to treat Parkinson's disease--bromocriptine, pergolide, pramipexole, ropinerole--usually reverse antipsychotic-induced prolactin increases without compromising psychiatric effectiveness.

Evidence that amphotericin B mediates reactivation of latent Epstein-Barr virus in Hodgkin's lymphoma allowing cytotoxicity by acyclovir

This brief communication focuses on aspects of a recent case report (Yonsei Med J 2005;46:425-30) on a full and sustained remission of Hodgkin's lymphoma (HL) after a single day of chemotherapy. A septic episode required stopping chemotherapy and starting amphotericin B and acyclovir. Remission evidence was seen within days of starting these. A review of research supporting the notion that amphotericin B can reactivate latent Epstein-Barr virus and thus allow acyclovir to kill infected HL cells is given. Experimental work is required to confirm or refute this possibility. If successful, amphotericin B and acyclovir treatment could be extended to other EBV-driven cancers such as Burkitt's lymphoma, nasopharyngeal carcinoma and the occasional EBV-related epithelial cancer of the breast, colon, prostate, and others.