Clinical pharmacology of asthma. Implications for treatment

Phosphodiesterase 4 inhibitors, structurally unrelated to rolipram, as promising agents for the treatment of asthma and other pathologies

An increase of cyclic adenosine and guanosine monophosphate (cAMP and cGMP) level can be achieved by inhibition of phosphodiesterases (PDEs), which are the enzymes responsible for the conversion of these second messengers into the corresponding 5-monophosphate inactive counterparts. The high heterogeneity in PDE families and in their tissue distribution, as well as their different functional role, make these enzymes very attractive targets for medicinal chemists. The PDE 4 family is particularly abundant in immunocompetent cells, where an increase of cAMP leads to the inhibition of the synthesis and release of pro-inflammatory mediators, cytokines and active oxygen species. Moreover PDE 4 inhibitors are able to reduce bronchial smooth muscle tone in vitro and show bronchodilatory effects in vivo. Thus, the current therapy for asthma, which is based on a combination of beta(2) agonists and corticosteroids, could be replaced by treatment with PDE 4 inhibitors. This review mainly covers PDE 4 inhibitors structurally related to xanthines and Nitraquazone, which appear to be very attractive models for the synthesis of novel PDE 4 inhibitors potentially useful for the treatment of asthma, chronic pulmonary obstructive disease and some autoimmune diseases. These compounds could be devoid of the central side-effects (nausea, vomiting, headache) of the archetypal Rolipram, which hampered its development as a drug. The review also highlights the novel structural classes of PDE 4 inhibitors recently reported in the literature.

Pain and Symptom Management in Palliative Care

BACKGROUND: Pain, dyspnea, and anorexia are common symptoms experienced by patients with cancer and often are poorly managed. METHODS: The incidence and causes of these symptoms are described, as well as factors that exacerbate or ameliorate their impact. RESULTS: Pharmacologic management of cancer pain is based on the use of a sequential "ladder" that incorporates nonopioid, opioid, and adjuvant drugs, depending on the severity of the pain. This approach usually is effective. Other symptoms of advanced disease may be more difficult to control. CONCLUSIONS: Adherence to an adequate pain-control strategy will significantly enhance palliation of pain in patients with cancer.