Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pyridostigmine bromide, a reversible inhibitor of acetylcholinesterase (AChE), is effectively used as a pre-treatment to organophosphate intoxication. Previous studies have shown that an oral dose of 30 mg twice a day produces a sufficient inhibition of the enzyme activity (20-40%) without causing any significant adverse effect. During the Persian Gulf war pyridostigmine was taken for the first time under a chemical warfare threat. We searched for symptoms and complaints that may be related to the medication. Our survey included 213 soldiers who completed a questionnaire regarding possible symptoms and their severity. AChE inhibition level was compared between groups of soldiers with and without complaints. The most frequent symptoms were nonspecific and included dry mouth, general malaise, fatigue and weakness. Typical effects, such as nausea, abdominal pain, frequent urination and rhinorrhea, were infrequent. The severity of the symptoms was generally mild. The symptoms appeared around 1.6 h after taking the medication and recurred after each intake. No correlation was found between levels of cholinesterase and type or severity of complaints. Anxiety, which accompanies wartime, may have contributed to the appearance of significant symptoms. Further investigations concerning the effects of pyridostigmine ingestion under stressful conditions are warranted.
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PMID:Survey of symptoms following intake of pyridostigmine during the Persian Gulf war. 175 41

Ocular myasthenia is a special form of general myasthenia gravis characterized by unilateral or bilateral ptosis and eye muscle pareses of distinct variability, depending on the time of day and the state of fatigue of the patient. Most important for diagnosis is the Tensilon test, which can, however, produce negative results. In such cases a combination of the Tensilon test with electromyography is indispensable. In ocular myasthenia there is not always an increase in the antibody titer against acetylcholine receptors in the blood. The treatment of ocular myasthenia is based on the application of cholinesterase inhibitors. The drug of choice is Mestinon; however, the reaction of the eye muscles to this drug is often unsatisfactory. Local application of cholinesterase inhibitors in the form of Eserine, Prostigmin etc. is an additional important therapy. Also in ocular myasthenia the modern treatment with Cortisone (alternate-day therapy with 100 mg Prednisone every second day) has proved very useful. Another possible method of interfering with the immunological systems of myasthenia is immunosuppression with Azathioprin or Cyclophosphamide. The pathognomonic significance of the thymus in the autoimmune process of myasthenia gravis is demonstrated by the good results obtained by thymectomy, which can also be performed successfully in ocular myasthenia, not only in young patients in whom the condition is severe, but also in older patients in whom it is chronic. Often, the therapeutic measures mentioned have to be tested one after another or in combination in order to achieve an optimal therapeutic effect.
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PMID:[Ocular myasthenia]. 399 98

Myasthenia gravis should be entertained as a possible diagnosis in any patient who presents with muscle weakness or visual disturbance. The most common symptom is exacerbation of muscle fatigue with repeated use of the muscle and improvement with rest. Several inexpensive diagnostic tests for myasthenia gravis that can be performed by primary care physicians are available. Standard therapy in most cases is early thymectomy, followed by a highly individualized medication program that usually includes the anticholinesterase drug pyridostigmine bromide (Mestinon, Regonol). Corticosteroids and other immunosuppressive agents (usually azathioprine [Imuran]) may be added or substituted if response to anticholinesterase therapy is inadequate. Although myasthenia gravis is a chronic disease, it can be well controlled in most patients, provided they comply with treatment. Patient education is therefore essential.
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PMID:Myasthenia gravis. Diagnostic methods and control measures for a chronic disease. 841 29

Pyridostigmine bromide (PB) is a reversible acetylcholinesterase (AChE) inhibitor and the first-choice for the treatment of symptoms associated with myasthenia gravis and other neuromuscular junction disorders. However, evidence suggested that PB could be associated with the Gulf War Illness characterised by the presence of fatigue, headaches, cognitive dysfunction, and musculoskeletal respiratory and gastrointestinal disturbances. Given that a potential neurotoxic effect of PB has not yet been completely elucidated, the present investigation used neural SH-SY5Y cells to evaluate the effect of PB on the cellular viability, cell apoptosis, modulation of the cell cycle, oxidative stress, and genotoxicity variables, which indicate neurodegeneration. As expected, a PB concentration curve based on the therapeutic dose of the drug showed an inhibition of the AChE activity. However, this effect was transient and did not involve differential AChE gene regulation by PB. These results confirmed that undifferentiated SH-SY5Y cells can be used as a cholinergic in vitro model. In general, PB did not trigger oxidative stress, and at a slightly higher PB concentration (80ng/mL), higher levels of protein carbonylation and DNA damage were detected, as determined by the marker 8-deoxyguanosine. The PB genotoxic effects at 80ng/mL were confirmed by the upregulation of the p53 and DNA methyltransferase 1 (DNMT1) genes, which are associated with cellular DNA repair. PB at 40ng/mL, which is the minimal therapeutic dose, led to higher cell proliferation and mitochondrial activity compared with the control group. The effects of PB were corroborated by the upregulation of the telomerase gene. In summary, despite the methodological constrains related to the in vitro protocols, our results suggested that exposure of neural cells to PB, without other chemical and physical stressors did not cause extensive toxicity or indicate any neurodegeneration patterns.
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PMID:Effects of Pyridostigmine bromide on SH-SY5Y cells: An in vitro neuroblastoma neurotoxicity model. 2898 42