ER signaling is activated to protect human HaCaT keratinocytes from ER stress induced by environmental doses of UVB.

Proteins are folded properly in the endoplasmic reticulum (ER). Various stress such as hypoxia, ischemia and starvation interfere with the ER function, causing ER stress, which is defined by the accumulation of unfolded protein (UP) in the ER. ER stress is prevented by the UP response (UPR) and ER-associated degradation (ERAD). These signaling pathways are activated by three major ER molecules, ATF6, IRE-1 and PERK. Using HaCaT cells, we investigated ER signaling in human keratinocytes irradiated by environmental doses of ultraviolet B (UVB). The expression of Ero1-L(alpha), an upstream signaling molecule of ER stress, decreased at 1-4h after 10 mJ/cm(2) irradiation, indicating that the environmental dose of UVB-induced ER stress in HaCaT cells, without growth retardation. Furthermore, expression of intact ATF6 was decreased and it was translocated to the nuclei. The expression of XBP-1, a downstream molecule of IRE-1, which is an ER chaperone whose expression is regulated by XBP-1, and UP ubiquitination were induced by 10 mJ/cm(2) UVB at 4h. PERK, which regulates apoptosis, was not phosphorylated. Our results demonstrate that UVB irradiation generates UP in HaCaT cells and that the UPR and ERAD systems are activated to protect cells from UVB-induced ER stress. This is the first report to show ER signaling in UVB-irradiated keratinocytes.

Minocycline attenuates both OGD-induced HMGB1 release and HMGB1-induced cell death in ischemic neuronal injury in PC12 cells.

High mobility group box-1 (HMGB1), a non-histone DNA-binding protein, is massively released into the extracellular space from neuronal cells after ischemic insult and exacerbates brain tissue damage in rats. Minocycline is a semisynthetic second-generation tetracycline antibiotic which has recently been shown to be a promising neuroprotective agent. In this study, we found that minocycline inhibited HMGB1 release in oxygen-glucose deprivation (OGD)-treated PC12 cells and triggered the activation of p38mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinases (ERK1/2). The ERK kinase (MEK)1/2 inhibitor U-0126 and p38MAPK inhibitor SB203580 blocked HMGB1 release in response to OGD. Furthermore, HMGB1 triggered cell death in a dose-dependent fashion. Minocycline significantly rescued HMGB1-induced cell death in a dose-dependent manner. In light of recent observations as well as the good safety profile of minocycline in humans, we propose that minocycline might play a potent neuroprotective role through the inhibition of HMGB1-induced neuronal cell death in cerebral infarction.

Edaravone attenuates cerebral ischemic injury by suppressing aquaporin-4.

Aquaporin-4 (AQP4) plays a role in the generation of post-ischemic edema. Pharmacological modulation of AQP4 function may thus provide a novel therapeutic strategy for the treatment of stroke, tumor-associated edema, epilepsy, traumatic brain injury, and other disorders of the central nervous system (CNS) associated with altered brain water balance. Edaravone, a free radical scavenger, is used for the treatment of acute ischemic stroke (AIS) in Japan. In this study, edaravone significantly reduced the infarct area and improved the neurological deficit scores at 24h after reperfusion in a rat transient focal ischemia model. Furthermore, edaravone markedly reduced AQP4 immunoreactivity and protein levels in the cerebral infarct area. In light of observations that edaravone specifically inhibited AQP4 in a rat transient focal ischemia model, we propose that edaravone might reduce cerebral edema through the inhibition of AQP4 expression following cerebral infarction.

Thrombomodulin exerts cytoprotective effect on low-dose UVB-irradiated HaCaT cells.

Thrombomodulin (TM) is an endothelial cell surface anticoagulant glycoprotein that performs antimetastatic, angiogenic, adhesive, and anti-inflammatory functions in various tissues. It is also expressed in epidermal keratinocytes. We found that a physiological dose (10mJ/cm(2)) of mid-wavelength ultraviolet irradiation (UVB) significantly induced TM expression via the p38mitogen-activated protein kinase (MAPK)/cyclic AMP response element (CRE) signaling pathway in the epidermal keratinocyte cell line HaCaT; this shows that TM regulates the survival of HaCaT cells. SB203580, a p38MAPK inhibitor, significantly decreased TM expression and the viability of cells exposed to UVB. Furthermore, overexpression of TM markedly increased cell viability, and it was abrogated by TM small interfering RNA (siRNA), suggesting that TM may play an important role in exerting cytoprotective effect on epidermal keratinocytes against low-dose UVB.

C-reactive protein induces high-mobility group box-1 protein release through activation of p38MAPK in macrophage RAW264.7 cells.

BACKGROUND: C-reactive protein (CRP) is widely used as a sensitive biomarker for inflammation. Increasing evidence suggests that CRP plays a role in inflammation. High-mobility group box-1 (HMGB1), a primarily nuclear protein, is passively released into the extracellular milieu by necrotic or damaged cells and is actively secreted by monocytes/macrophages. Extracellular HMGB1 as a potent inflammatory mediator has stimulated immense curiosity in the field of inflammation research. However, the molecular dialogue implicated between CRP and HMGB1 in delayed inflammatory processes remains to be explored. METHODS AND RESULTS: The levels of HMGB1 in culture supernatants were determined by Western blot analysis and enzyme-linked immunosorbent assay in macrophage RAW264.7 cells. Purified CRP induced the release of HMGB1 in a dose- and time-dependent fashion. Immunofluorescence analysis revealed nuclear translocation of HMGB1 in response to CRP. The binding of CRP to the Fc gamma receptor in RAW264.7 cells was confirmed by fluorescence-activated cell sorter analysis. Pretreatment of cells with IgG-Fc fragment, but not IgG-Fab fragment, efficiently blocked this binding. CRP triggered the activation of p38MAPK and ERK1/2, but not Jun N-terminal kinase. Moreover, both p38MAPK inhibitor SB203580 and small interfering RNA significantly suppressed the release of HMGB1, but not the MEK1/2 inhibitor U-0126. CONCLUSION: We demonstrated for the first time that CRP, a prominent risk marker for inflammation including atherosclerosis, could induce the active release of HMGB1 by RAW264.7 cells through Fc gamma receptor/p38MAPK signaling pathways, thus implying that CRP plays a crucial role in the induction, amplification, and prolongation of inflammatory processes, including atherosclerotic lesions.

Case of adult T-cell leukemia with pulmonary involvement presenting as nodular shadows.

A 60-year-old man with a diagnosis of smoldering adult T-cell leukemia (ATL) had been treated successfully for 4 years with psoralen and ultraviolet A therapy, gamma-interferon, oral etoposide and sobuzoxane. He subsequently developed rapidly-growing skin nodules over his entire body. Chest X-ray and thoracic computed tomography showed nodular shadows in the right lower lung field and nodules in both lower lung lobes. Despite combined chemotherapy, he died. Upon autopsy, numerous nodules were found in the bilateral lower lobes; microscopically, the nodules were diffusely infiltrated by ATL cells. Our review of the published work found only two previously reported cases of ATL with pulmonary involvement manifested as nodular shadows. Herein, we present details on the third case.

Granulomas induced by subcutaneous injection of leuprorelin acetate.

Leuprorelin acetate, a chemotherapeutic agent used to treat prostate cancer, is a synthetic luteinizing hormone-releasing hormone (LHRH) agonist. We report a 75-year-old man who presented with several large subcutaneous nodules at the site of leuprorelin acetate injections for his prostatic cancer. A biopsy of the nodules disclosed epithelioid granulomatous inflammation and resulted in a diagnosis of drug-induced granulomatous reaction to leuprorelin acetate.

Extramammary Paget's disease/carcinoma successfully treated with a combination chemotherapy: report of two cases.

We have treated two patients with extramammary Paget's disease/carcinoma (EMPD/C), a 62-year-old woman and a 78-year-old man. In both patients, lymph nodes in the areas of the bilateral inguinal, external iliac arteries, and abdominal aorta were affected. After surgery, they underwent 5 courses of systemic combination chemotherapy at 4-week intervals to residual or recurrent lymph node metastasis. Each course consisted of 3.5 mg mitomycin C and 50 mg epirubicin (day 1), 0.6 mg vincristine (days 1 and 7), 30 mg cisplatin (days 1, 2, and 3), and 350 mg 5-fluorouracil (days 3, 4, 5, 6, and 7). The affected lymph nodes in both patients subsided in response to the chemotherapy. Positron emission tomography (PET) scans confirmed the complete remission of lymph node metastasis in Case 1. In Case 2, they were reduced by more than 90% on computed tomography (CT) scans. Adverse effects included leukocytopenia, vomiting, hypesthesia, and constipation, all of which disappeared after the completion of chemotherapy. While surgery with wide local excision is the treatment of choice in patients with EMPD/C, there is currently no standardized treatment for advanced cases with metastasis. We describe two patients with EMPD/C whose metastatic lesions responded well to this combination of chemotherapy.

1,5-Anhydro-D-fructose: A natural antibiotic that inhibits the growth of gram-positive bacteria and microbial biofilm formation to prevent nosocomial infection.

Nosocomial infections caused by microbial opportunistic infections or microbial biofilms may occur during hospitalization and increase patient morbidity, mortality and health care costs. Artificial antibiotic agents were initially used to prevent infection; however, the high prevalence of nosocomial infections has resulted in their excessive use, which has led to microbial resistance to these agents. The increase in microbial resistance to antibiotics and the development of antibiotic agents may be the cause of the production of other microbial resistance. Thus, natural compounds that have no adverse side effects would be a preferred treatment modality. Recently, the monosaccharide 1,5-anhydro-D-fructose (1,5-AF), a natural plant compound derived from starch, has been found to have multifunctional properties, including antioxidant, antiplatelet aggregation by thrombin and anti-inflammatory activities. The results of the present study demonstrate that 1,5-AF suppressed the growth of coagulase-negative staphylococci on the hands as well as the growth of Staphylococcus epidermidis, which is a cause of opportunistic infections. Furthermore, 1,5-AF suppressed biofilm formation by the methicillin-resistant Staphylococcus aureus. In conclusion, 1,5-AF is a natural compound that may be effective in preventing nosocomial infections, without causing adverse side effects.

Potential of edaravone for neuroprotection in neurologic diseases that do not involve cerebral infarction.

Edaravone was originally developed as a potent free radical scavenger and has been widely used to treat cerebral infarction in Japan since 2001. Several free radical scavengers have been developed and some of them have progressed to clinical trials for the treatment of cerebral infarction. One such scavenger, edaravone, has been approved by the regulatory authority in Japan for the treatment of patients with cerebral infarction. Of particular interest is the ability of edaravone to diffuse into the central nervous system in various neurologic diseases. Aside from its hydroxyl radical scavenging effect, edaravone has been found to have beneficial effects on inflammation, matrix metalloproteinases, nitric oxide production and apoptotic cell death. Concordantly, edaravone has been found to have neuroprotective effects in a number of animal models of disease, including stroke, spinal cord injury, traumatic brain injury, neurodegenerative diseases and brain tumors. The proven safety of edaravone following 9 years of use as a free radical scavenger suggests that it may have potential for development into an effective treatment of multiple neurologic conditions in humans.

Metastatic cutaneous squamous cell carcinoma treated successfully with surgery, radiotherapy and S-1/cisplatin chemotherapy.

Primary cutaneous squamous cell carcinoma (SCC) is a malignant tumor that arises from keratinizing cells of the epidermis or its appendages. We present a patient with cutaneous SCC on the left instep with metastases to multiple lymph nodes in the para-aortic, iliac and groin region. We chose a combination of surgery and concurrent chemoradiotherapy. The chemotherapeutic agent S-1/cisplatin was selected based on results of the histoculture drug response assay. The patient responded dramatically to this multidisciplinary treatment and complete remission was achieved.

Edaravone: a new therapeutic approach for the treatment of acute stroke.

Acute stroke, including acute ischemic stroke (AIS) and acute hemorrhagic stroke, (AHS) is a common medical problem with particular relevance to the demographic changes in industrialized societies. In recent years, treatments for AIS have emerged, including thrombolysis with tissue plasminogen activator (t-PA). Although t-PA is the most effective currently available therapy, it is limited by a narrow therapeutic time window and side effects, and only 3% of all AIS patients receive thrombolysis. Edaravone was originally developed as a potent free radical scavenger and, since 2001, has been widely used to treat AIS in Japan. It was shown that edaravone extended the narrow therapeutic time window of t-PA in rats. The therapeutic time window is very important for the treatment of AIS, and early edaravone treatment is more effective. Thus, more AIS patients might be rescued by administering edaravone with t-PA. Meanwhile, edaravone attenuates AHS-induced brain edema, neurologic deficits and oxidative injury in rats. Although edaravone treatment is currently only indicated for AIS, it does offer neuroprotective effects against AHS in rats. Therefore, we hypothesize that early administration of edaravone can rescue AHS patients as well as AIS patients. Taken together, our findings suggest that edaravone should be immediately administered on suspicion of acute stroke, including AIS and AHS.

HMGB1: A new marker for estimation of the postmortem interval.

Estimation of the postmortem interval (PMI) is one of the most important tasks in forensic medicine. Numerous methods have been proposed for the determination of the time since death by chemical means. High mobility group box-1 (HMGB1), a nonhistone DNA-binding protein is released by eukaryotic cells upon necrosis. Postmortem serum levels of HMGB1 of 90 male Wistar rats stored at 4, 14 and 24°C since death were measured by enzyme-linked immunosorbent assay. The serum HMGB1 level showed a time-dependent increase up to seven days at 4°C. At 14°C, the HMGB1 level peaked at day 3, decreased at day 4, and then plateaued. At 24°C, the HMGB1 level peaked at day 2, decreased at day 3, and then plateaued. Our findings suggest that HMGB1 is related to the PMI in rats.