In Vitro and in Vivo Study of a Photostable Quinone Compound with Enhanced Therapeutic Efficacy against Chagas Disease.

Chagas disease, a neglected tropical disease caused by the protozoan Trypanosoma cruzi poses a significant health challenge in rural areas of Latin America. The current pharmacological options exhibit notable side effects, demand prolonged administration, and display limited efficacy. Consequently, there is an urgent need to develop drugs that are safe and clinically effective. Previously, we identified a quinone compound (designated as compound 2) with potent antiprotozoal activity, based on the chemical structure of komaroviquinone, a natural product renowned for its antitrypanosomal effects. However, compound 2 was demonstrated considerably unstable to light. In this study, we elucidated the structure of the light-induced degradation products of compound 2 and probed the correlation between the quinone ring's substituents and its susceptibility to light. Our findings led to the discovery of quinones with significantly enhanced light stability, some of which exhibiting antitrypanosomal activity. The most promising compound was evaluated for drug efficacy in a mouse model of Chagas disease, revealing where a notable reduction in blood parasitemia.

GTN057, a komaroviquinone derivative, induced myeloma cells' death in vivo and inhibited c-MET tyrosine kinase.

OBJECTIVE: Despite the development of newly developed drugs, most multiple myeloma (MM) patients with high-risk cytogenetic abnormalities such as t(4;14) or del17p relapse at anin early stage of their clinical course. We previously reported that a natural product,komaroviquinone (KQN), isolated from the perennial semi-shrub Dracocephalum komarovi, i.e., komaroviquinone (KQN) and its derivative GTN024 induced the apoptosis of MM cells by producing reactive oxygen species (ROS), but both exhibited significant hematological toxicity. Aim of this study is to clarify anti-tumor activity, safety and pharmacokinetics of GTN057, an optimization compound of KQN in vivo. METHODS: ICR/SCID xenograft model of KMS11, a t(4;14) translocation-positive MM cell line, was used for in vivo study. Mice pharmacokinetics of GTN057 and the degradation products were analyzed by LC-MS/MS. RESULTS: Herein, our in vitro experiments revealed that GTN057 is much less toxic to normal hematopoietic cells, induced the apoptosis of both MM cell lines andpatient samples, including those with high-risk cytogenetic changes. A xenograft model of a high-risk MM cell line demonstrated that GTN057 significantly delayed the tumor growth with no apparent hematological or systemic toxicities in vivo. The pathological examination of GTN057-treated tumors in vivoshowed revealed apoptosis of MM cells and anti-angiogenesis. In addition to the production of ROS, GTN057 inhibited the downstream signaling of c-MET, a receptor tyrosine kinase a receptor forand hepatocyte growth factor (HGF) receptor. Thus, GTN057 is less toxic and is able tomay be a candidate drug for treating MM patients, via multifunctional mechanisms. We have also extensively studied the pharmacologyical analysis of GTN057. The metabolites of GTN057, (e.g.,such as GTN054), may also have anti-tumorantitumor activity. CONCLUSION: Natural products or and their derivatives can could be good sources of antineoplastic drugs even for high-risk cancer.

[Surgical considerations for two patients with cardioembolic stroke and mobile thrombus in the left atrium appendage].

Two men (Case 1, 74 years old; Case 2, 65 years old) developed cardioembolic stroke due to self-interruption of anticoagulants for treating atrial fibrillation. They both had mobile thrombus in the left atrial appendage. In Case 1, a left atrial thrombectomy was scheduled on day 8, but infarction re-occurred on the morning of the the surgery, producing neurological sequelae. In Case 2, left atrial thrombectomy and left atrial appendage closure were performed successfully on day 8. The indication and timing of cardiac thrombectomy after the onset of cerebral infarction have not been standardized, and they seem to differ among individuals. Therefore, in the future, the optimal timing of left atrial thrombectomy should be decided based on the size and morphology of the left atrial thrombus, the size of the cerebral infarction and the presence or absence of hemorrhagic infarction.

A novel derivative (GTN024) from a natural product, komaroviquinone, induced the apoptosis of high-risk myeloma cells via reactive oxygen production and ER stress.

New drugs have significantly improved the survival of patients with multiple myeloma (MM), but the prognosis of MM patients with high-risk cytogenetic changes such as t(4; 14), t(14; 16) or del17p remains very poor. A natural product, komaroviquinone (KQN), was originally isolated from the perennial semi-shrub Dracocephalum komarovi and has anti-protozoal activity against Trypanosoma cruzi, the organism causing Chagas' disease. Here we demonstrate that a novel KQN-derivative, GTN024, has an anti-MM effect both in vitro and in vivo. GTN024 induced the apoptosis of MM cell lines including those with high-risk cytogenetic changes. GTN024 produced reactive oxygen species (ROS) and increased phosphorylated eIF2α. The ROS production and subsequent endoplasmic reticulum (ER) stress are thought to play a key role in GTN024-induced apoptosis, as the apoptosis was completely abrogated by anti-oxidant treatment. In a mouse xenograft model, an intraperitoneal injection of 20 mg/kg of GTN024 significantly delayed tumor growth. Hematological toxicity and systemic toxicity as indicated by weight loss were not observed. These results suggest that the novel KQN-derivative GTN024 could become a candidate drug for treating high-risk MM.

Synthesis and biological evaluation of the natural product komaroviquinone and related compounds aiming at a potential therapeutic lead compound for high-risk multiple myeloma.

Alternatives of treatments for multiple myeloma (MM) have become increasingly available with the advent of new drugs such as proteasome inhibitors, thalidomide derivatives, histone deacetylase inhibitors, and antibody drugs. However, high-risk MM cases that are refractory to novel drugs remain, and further optimization of chemotherapeutics is urgently needed. We had achieved asymmetric total synthesis of komaroviquinone, which is a natural product from the plant Dracocephalum komarovi. Similar to several leading antitumor agents that have been developed from natural compounds, we describe the antitumor activity and cytotoxicity of komaroviquinone and related compounds in bone marrow cells. Our data suggested that komaroviquinone-related agents have potential as starting compounds for anticancer drug development.

Clinicopathological features of adult-onset neuronal intranuclear inclusion disease.

Neuronal intranuclear inclusion disease (NIID) is a slowly progressive neurodegenerative disease characterized by eosinophilic hyaline intranuclear inclusions in the central and peripheral nervous system, and also in the visceral organs. NIID has been considered to be a heterogeneous disease because of the highly variable clinical manifestations, and ante-mortem diagnosis has been difficult. However, since we reported the usefulness of skin biopsy for the diagnosis of NIID, the number of NIID diagnoses has increased, in particular adult-onset NIID. In this study, we studied 57 cases of adult-onset NIID and described their clinical and pathological features. We analysed both NIID cases diagnosed by post-mortem dissection and by ante-mortem skin biopsy based on the presence of characteristic eosinophilic, hyaline and ubiquitin-positive intanuclear inclusion: 38 sporadic cases and 19 familial cases, from six families. In the sporadic NIID cases with onset age from 51 to 76, dementia was the most prominent initial symptom (94.7%) as designated 'dementia dominant group', followed by miosis, ataxia and unconsciousness. Muscle weakness and sensory disturbance were also observed. It was observed that, in familial NIID cases with onset age less than 40 years, muscle weakness was seen most frequently (100%), as designated 'limb weakness group', followed by sensory disturbance, miosis, bladder dysfunction, and dementia. In familial cases with more than 40 years of onset age, dementia was most prominent (100%). Elevated cerebrospinal fluid protein and abnormal nerve conduction were frequently observed in both sporadic and familial NIID cases. Head magnetic resonance imaging showed high intensity signal in corticomedullary junction in diffusion-weighted image in both sporadic and familial NIID cases, a strong clue to the diagnosis. All of the dementia dominant cases presented with this type of leukoencephalopathy on head magnetic resonance imaging. Both sporadic and familial NIID cases presented with a decline in Mini-Mental State Examination and Frontal Assessment Battery scores. Based on these clinicopathological features, we proposed a diagnosis flow chart of adult-onset NIID. Our study suggested that the prevalence rate of adult-onset NIID may be higher than previously thought, and that NIID may be underdiagnosed. We should take NIID into account for differential diagnosis of leukoencephalopathy and neuropathy.

Acute Motor-dominant Polyneuropathy as Guillain-Barré Syndrome and Multiple Mononeuropathies in a Patient with Sjögren's Syndrome.

A patient with xerostomia and xerophthalmia due to Sjögren's syndrome presented with acute motor-dominant polyneuropathy and multiple mononeuropathy with antiganglioside antibodies. Nerve conduction studies and a sural nerve biopsy revealed the neuropathy as a mixture of segmental demyelination and axonal degeneration. Positive results were obtained for several antiganglioside antibodies. Corticosteroid treatment proved effective. The neuropathy was considered to represent a mixture of polyneuropathy as Guillain-Barré syndrome and multiple mononeuropathy via Sjögren's syndrome. We speculate that Guillain-Barré syndrome occurred in the patient and Guillain-Barré syndrome itself activated multiple mononeuropathy via Sjögren's syndrome.

[A case of tuberculous myeloradiculitis with abdominal lymphadenitis presenting with symptoms of radiculomyelopathy].

A 30-year old man was admitted with right hip pain and gait disturbances. Neurological findings revealed muscular weakness in the lower limbs, hyporeflexia, dysesthesia in the sacral region, and bowel and bladder disturbances. Cerebrospinal fluid (CSF) examination indicated a white blood cell count of 371/µl (lymphocyte:polymorphonuclear leukocyte = 97:3), protein levels of 463 mg/dl and sugar of 20 mg/dl. Although CSF culture was negative, tuberculous infection was presumed. Magnetic resonance imaging revealed areas of enhancement in the intramedullary region surrounding the spinal cord and cauda equina. Enhanced computed tomography (CT) of the abdomen revealed lymph node swelling around the head of the pancreas. Biopsy of the lymph node swelling was culture-positive for Mycobacterium tuberculosis. Hence, assuming a diagnosis of tuberculous lymphadenitis of the abdomen, antitubercular drugs were started. Since antitubercular therapy had beneficial effects on the neurological symptoms and CSF findings, we diagnosed the patient with tuberculous myeloradiculitis. Systematic examinations including lymph node biopsy and cultures were useful for the diagnosis of tuberculous myeloradiculitis.

Plasma Brain Natriuretic Peptide is a Marker of Prognostic Functional Outcome in Non-Cardioembolic Infarction.

BACKGROUND: High plasma levels of brain natriuretic peptide (BNP) may also be observed in patients with non-cardioembolic infarction (CEI). We aimed to evaluate the relation between plasma BNP level, clinical parameters, and functional outcome in patients with and without CEI. METHOD: This study analyzed consecutive Japanese patients with acute ischemic stroke. Correlations between plasma BNP level and conventional risk factors for ischemic stroke were examined. Values of P less than .05 were considered statistically significant. RESULTS: This study analyzed 718 acute ischemic stroke patients (445 men and 273 women; mean age, 73.9 years). Mean plasma level of BNP was significantly higher for CEI (366.6 pg/ml) than for non-CEI (105.6 pg/ml; P < .01). Poor outcome (modified Rankin Scale score ≥3) at hospitalization and discharge were associated with significantly higher plasma BNP level than good outcome (modified Rankin Scale score ≤2) for both CEI and non-CEI. On multiple regression analysis, log-BNP was significantly associated with female sex, smoking, triglyceride, and creatinine clearance in CEI. In non-CEI, log-BNP was significantly associated with systolic/diastolic blood pressure, triglyceride, high-density lipoprotein cholesterol, and creatinine clearance. CONCLUSION: Irrespective of the presence of CEI, plasma BNP offers a marker of prognostic functional outcome. We clarified the characteristics and differences associated with plasma BNP in CEI and non-CEI, and our results suggest that plasma BNP can provide a useful marker of brain damage and neurohumoral dynamics in acute ischemic stroke.

Emergency superficial temporal artery to middle cerebral artery bypass after intravenous recombinant tissue plasminogen activator administration for acute cerebral ischemia in a patient with moyamoya disease.

There are few study data to help in the decision whether to perform aggressive surgical revascularization, such as emergency bypass, after intravenous recombinant tissue plasminogen activator (rt-PA) administration in patients with progressive symptoms due to acute cerebral ischemia. A 33-year-old healthy male with no known previous medical history developed right hemiparesis and motor aphasia. No acute lesion was observed on admission computed tomography. According to the treatment protocol, emergency intravenous rt-PA administration was indicated within 3 h. After rt-PA administration, symptoms progressed to complete right hemiplegia. Emergency magnetic resonance imaging (MRI) showed an acute ischemic lesion in the left basal ganglia. MR angiography showed severe stenosis of the bilateral terminal portion of the internal carotid artery and occlusion of the left middle cerebral artery (MCA). Obvious diffusion-perfusion mismatch was detected. We performed digital subtraction angiography and diagnosed this condition as acute cerebral ischemia induced by moyamoya disease. We decided to perform emergency superficial temporal artery (STA)-MCA bypass to prevent further damage. The operation began 7 h after the administration of rt-PA and successful bypass was achieved. Symptoms stabilized and improved postoperatively. The majority of the area with preoperative hypoperfusion was rescued. Four months after surgery, the patient resumed his previous employment and continues to do well after 1.5 years of follow-up. This is the first report of emergency STA-MCA bypass performed after intravenous rt-PA administration for acute cerebral ischemia in a patient with moyamoya disease. We conclude that emergency STA-MCA bypass is a viable option for patients with moyamoya disease even after administration of rt-PA.

JmjC enzyme KDM2A is a regulator of rRNA transcription in response to starvation.

The rate-limiting step in ribosome biogenesis is the transcription of ribosomal RNA, which is controlled by environmental conditions. The JmjC enzyme KDM2A/JHDM1A/FbxL11 demethylates mono- and dimethylated Lys 36 of histone H3, but its function is unclear. Here, we show that KDM2A represses the transcription of ribosomal RNA. KDM2A was localized in nucleoli and bound to the ribosomal RNA gene promoter. Overexpression of KDM2A repressed the transcription of ribosomal RNA in a demethylase activity-dependent manner. When ribosomal RNA transcription was reduced under starvation, a cell-permeable succinate that inhibited the demethylase activity of KDM2A prevented the reduction of ribosomal RNA transcription. Starvation reduced the levels of mono- and dimethylated Lys 36 of histone H3 marks on the rDNA promoter, and treatment with the cell-permeable succinate suppressed the reduction of the marks during starvation. The knockdown of KDM2A increased mono- and dimethylated Lys 36 of histone H3 marks, and suppressed the reduction of ribosomal RNA transcription under starvation. These results show a novel mechanism by which KDM2A activity is stimulated by starvation to reduce ribosomal RNA transcription.

Myasthenia gravis with thymus hyperplasia and pure red cell aplasia.

A case of myasthenia gravis (MG) with thymus hyperplasia and pure red cell aplasia (PRCA) is reported. A 57-year-old woman was diagnosed as having MG and was treated with thymectomy 26 years ago. The histology of the resected thymus was thymic lymphoid follicular hyperplasia. She developed rapidly progressive anemia and a bone marrow examination revealed PRCA. Her hematological results improved with oral administration of cyclosporine A. Cases of MG, thymoma and PRCA have been reported in the literature. We report the first case of MG without thymoma and PRCA.

Dramatic switching of protein kinase C agonist/antagonist activity by modifying the 12-ester side chain of phorbol esters.

A dramatic switching of PKC agonist and antagonist activity was observed by modification of the hydrophilicity of the 12-ester side chain of phorbol. Thus, phorbol ester 4 that contains a glycol at the 12-ester chain demonstrated a pure and significant antagonist ability of PKC; however, 3 that contains an alkanol at the 12-ester chain demonstrated a potent PKC agonist activity. On the basis of the structural difference between 3 and 4 and results of the partition assay in the Hela cell/PBS buffer system, we propose that 4 acts as a translocation poison of the PKC-phorbol ester complex. The approach of controlling the agonist/antagonist activity of phorbol esters by the nature (i.e., hydrophilicity, charge, and rigidity, etc.) of the 12-ester chain may be very useful for developing selective PKC inhibitors and a potential pharmaceutical compound for anticancer therapies.