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

A 43-year-old man underwent living related-donor renal transplantation because of chronic renal failure in 1991. During the transplant period, both donor and recipient were seronegative for hepatitis B surface antigen (HBsAg). The donor was seropositive for antibody to hepatitis B surface antigen (anti-HBs) due to hepatitis B virus (HBV) vaccination. After transplantation, FK506 and methylprednisolone had been administered to the patient as immunosuppressants. In 1993, HBsAg appeared in his serum. His alanine aminotransferase level elevated gradually during 1995 and then in 1996, general fatigue, ascites and jaundice developed. At this time his serum was positive for hepatitis B e antibody, contained more than 100000 Meq/mL HBV-DNA and 100% precore mutant. Despite subsequent intensive therapy, liver dysfunction progressed and this patient died of hepatic failure 2 months following admission. At autopsy, the liver exhibited cholestasis, fibrosis extending from the portal tracts, mild inflammation and hepatocytes with a ground-glass appearance. In addition, HBsAg and hepatitis B core antigens had accumulated in the hepatocytes. Consequently, the final diagnosis was fibrosing cholestatic hepatitis (FCH) due to precore mutant HBV infection contracted after renal transplantation. It is unclear when and where the recipient liver became HBV infected. Nevertheless, after renal transplantation, while receiving immunosuppressive drugs, HBV appeared to have the potential to cause hepatic failure and FCH may have been a fatal complication for the recipient.
 ...
PMID:Fibrosing cholestatic hepatitis after living related-donor renal transplantation. 987 Aug 1

The type 1 ryanodine receptor (RyR1) on the sarcoplasmic reticulum (SR) is the major calcium (Ca2+) release channel required for skeletal muscle excitation-contraction (EC) coupling. RyR1 function is modulated by proteins that bind to its large cytoplasmic scaffold domain, including the FK506 binding protein (FKBP12) and PKA. PKA is activated during sympathetic nervous system (SNS) stimulation. We show that PKA phosphorylation of RyR1 at Ser2843 activates the channel by releasing FKBP12. When FKB12 is bound to RyR1, it inhibits the channel by stabilizing its closed state. RyR1 in skeletal muscle from animals with heart failure (HF), a chronic hyperadrenergic state, were PKA hyperphosphorylated, depleted of FKBP12, and exhibited increased activity, suggesting that the channels are "leaky." RyR1 PKA hyperphosphorylation correlated with impaired SR Ca2+ release and early fatigue in HF skeletal muscle. These findings identify a novel mechanism that regulates RyR1 function via PKA phosphorylation in response to SNS stimulation. PKA hyperphosphorylation of RyR1 may contribute to impaired skeletal muscle function in HF, suggesting that a generalized EC coupling myopathy may play a role in HF.
 ...
PMID:PKA phosphorylation activates the calcium release channel (ryanodine receptor) in skeletal muscle: defective regulation in heart failure. 1262 52

Injury to the adult CNS often involves death of motoneurons, resulting in the paralysis and progressive atrophy of muscle. There is no effective therapy to replace motoneurons in the CNS. Our strategy to replace neurons and to rescue denervated muscles is to transplant dissociated embryonic day 14-15 (E14-15) ventral spinal cord cells into the distal stump of a peripheral nerve near the denervated muscles. Here, we test whether long-term delivery of two pharmacological inhibitors to denervated muscle, FK506 or SB203580, enhances reinnervation of muscle from embryonic cells transplanted in the tibial nerve of adult Fischer rats. FK506, SB203580 (2.5 mg/kg) or saline was delivered under the fascia of the medial gastrocnemius muscle for 4 weeks, beginning when muscles were denervated by section of the sciatic nerve. After 1 week of nerve degeneration, one million E14-15 ventral spinal cord cells were transplanted into the distal tibial nerve stump of each rat in the three treatment groups. Ten weeks later, all cell transplants had neuron-specific nuclear protein (NeuN) positive neurons. Neuron survival and axon regeneration were similar across treatments. An average (+/-S.E.) of 210+/-66, 100+/-36 and 176+/-58 myelinated axons grew distally from the cell transplants of rats with muscles treated with FK506, SB203580 or saline, respectively. Regenerating axons in muscles of all three treatments groups were detected with antibodies against phosphorylated neurofilaments and synaptophysin, and motor end plates were labeled with alpha-bungarotoxin. Muscles of rats that received transplants of media only had no axon growth, indicating that the muscles were denervated. The mean muscle fiber areas of rats that received cell transplants and had long-term delivery of FK506, SB203580 or saline to muscles were significantly larger than those of denervated muscle fibers. Thus, cell transplantation reduced muscle atrophy. Transplantation of embryonic cells also resulted in functional muscle reinnervation. Electromyographic activity and force were evoked from >90% of the muscles of rats with cell transplants, but not from denervated muscles. FK506-treated muscles were significantly more fatigue resistant than naive control muscles. FK506-treated muscles also had significantly stronger motor units than those in SB203580 or saline-treated muscles. These data suggest that a pathway regulated by FK506 improves the function of muscles reinnervated by embryonic neurons placed in peripheral nerve.
 ...
PMID:The immunophilin ligand FK506, but not the P38 kinase inhibitor SB203580, improves function of adult rat muscle reinnervated from transplants of embryonic neurons. 1559 Jan 46

Under immunosuppressive conditions after hematopoietic stem cell transplantation (HSCT), even if hepatitis B virus (HBV) antigen is negative but hepatitis B surface antibody (HBsAb) or hepatitis B core antibody (HBcAb) is presented, HBV reactivates and sometimes causes fulminant hepatitis. However, it remains unclear which patients will develop fulminant hepatitis, or whether fulminant hepatitis is caused by host-related factors or by virus-related factors. A 30-yr-old man with a history of aplastic anemia since 3 yr of age underwent allogenic BMT, when HBsAb and HBcAb were positive but HBs antigen (HBsAg) was negative. The donor was negative for HBsAg, HBsAb and HBcAb. After transplantation, the patient was complicated by acute graft-vs.-host disease (GVHD), cytomegalovirus infection, intestinal thrombotic microangiopathy and aspergillus colitis. Chronic GVHD was well controlled by FK506 and prednisolone. Twenty months after transplantation, the patient was admitted with general fatigue and liver dysfunction and was found to be positive for HBsAg and HBeAg. His serum HBV-DNA level was >8.8 log of the genome equivalent (LGE)/mL. Therefore, he was diagnosed as having hepatitis B caused by HBV reactivation and 100 mg/d lamivudine treatment was started. However, jaundice and hepatic failure deteriorated and became fatal. On analysis of the HBV-DNA, two adjacent gene mutations in the core promoter region (T1762/A1764) were detected. Increased replication of the mutated HBV might have caused HBV reactivation which progressed to fulminant hepatitis.
 ...
PMID:Fulminant hepatitis after allogenic bone marrow transplantation caused by reactivation of hepatitis B virus with gene mutations in the core promotor region. 1692 12