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1.
Cell Rep ; 43(4): 113981, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38520688

RESUMO

Cholera toxin (CT), a bacterial exotoxin composed of one A subunit (CTA) and five B subunits (CTB), functions as an immune adjuvant. CTB can induce production of interleukin-1ß (IL-1ß), a proinflammatory cytokine, in synergy with a lipopolysaccharide (LPS), from resident peritoneal macrophages (RPMs) through the pyrin and NLRP3 inflammasomes. However, how CTB or CT activates these inflammasomes in the macrophages has been unclear. Here, we clarify the roles of inositol-requiring enzyme 1 alpha (IRE1α), an endoplasmic reticulum (ER) stress sensor, in CT-induced IL-1ß production in RPMs. In RPMs, CTB is incorporated into the ER and induces ER stress responses, depending on GM1, a cell membrane ganglioside. IRE1α-deficient RPMs show a significant impairment of CT- or CTB-induced IL-1ß production, indicating that IRE1α is required for CT- or CTB-induced IL-1ß production in RPMs. This study demonstrates the critical roles of IRE1α in activation of both NLRP3 and pyrin inflammasomes in tissue-resident macrophages.


Assuntos
Toxina da Cólera , Estresse do Retículo Endoplasmático , Endorribonucleases , Interleucina-1beta , Proteínas Serina-Treonina Quinases , Interleucina-1beta/metabolismo , Animais , Endorribonucleases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Camundongos , Toxina da Cólera/farmacologia , Toxina da Cólera/metabolismo , Inflamassomos/metabolismo , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Lipopolissacarídeos/farmacologia , Retículo Endoplasmático/metabolismo
2.
Nat Commun ; 15(1): 1098, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321030

RESUMO

In angiosperms, the transition from floral-organ maintenance to abscission determines reproductive success and seed dispersion. For petal abscission, cell-fate decisions specifically at the petal-cell base are more important than organ-level senescence or cell death in petals. However, how this transition is regulated remains unclear. Here, we identify a jasmonic acid (JA)-regulated chromatin-state switch at the base of Arabidopsis petals that directs local cell-fate determination via autophagy. During petal maintenance, co-repressors of JA signaling accumulate at the base of petals to block MYC activity, leading to lower levels of ROS. JA acts as an airborne signaling molecule transmitted from stamens to petals, accumulating primarily in petal bases to trigger chromatin remodeling. This allows MYC transcription factors to promote chromatin accessibility for downstream targets, including NAC DOMAIN-CONTAINING PROTEIN102 (ANAC102). ANAC102 accumulates specifically at the petal base prior to abscission and triggers ROS accumulation and cell death via AUTOPHAGY-RELATED GENEs induction. Developmentally induced autophagy at the petal base causes maturation, vacuolar delivery, and breakdown of autophagosomes for terminal cell differentiation. Dynamic changes in vesicles and cytoplasmic components in the vacuole occur in many plants, suggesting JA-NAC-mediated local cell-fate determination by autophagy may be conserved in angiosperms.


Assuntos
Arabidopsis , Ciclopentanos , Oxilipinas , Arabidopsis/genética , Flores/genética , Espécies Reativas de Oxigênio/metabolismo , Autofagia , Cromatina/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Case Rep Oncol ; 16(1): 1482-1488, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028581

RESUMO

Introduction: Metaplastic breast carcinoma (MBC) is a rare histologic subtype of breast carcinoma, which is usually negative for estrogen receptor, progesterone receptor, and HER2. HER2-positive MBC is therefore extremely rare. Most MBCs have poor response to chemotherapy. HER2-targeted neoadjuvant chemotherapy (NAC) is widely performed and has high efficacy in treating HER2-positive breast cancer. We report an atypical case of HER2-positive breast cancer that had poor response to NAC and was diagnosed with MBC after the surgery. Case Presentation: A 73-year-old woman noticed a mass in her right breast and visited our hospital. The mass was diagnosed as hormone receptor-negative, HER2-positive invasive ductal carcinoma, T2N0M0 stage IIA. She received HER2-targeted NAC comprising trastuzumab + pertuzumab + docetaxel. Despite three courses, we observed disease progression. The next NAC regimen was composed of two courses of epirubicin + cyclophosphamide, but the cancer continued to grow. She stopped receiving NAC and underwent a unilateral mastectomy and sentinel lymph node biopsy. Although the preoperative pathological result of core needle biopsy specimen showed invasive ductal carcinoma, the postoperative pathological result of the surgical specimen was MBC. Conclusion: In this case, when the patient had undergone three courses of trastuzumab + pertuzumab + docetaxel, it would have been appropriate to review the result of the core needle biopsy with pathologists or to perform vacuum-assisted breast biopsy. This case suggests the importance of considering the possibility of special histologic subtypes such as MBC when a tumor with the diagnosis of invasive ductal carcinoma is resistant to NAC.

4.
Respirol Case Rep ; 11(8): e01185, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37408692

RESUMO

A 72-year-old man was diagnosed with hypercalcaemia 13 years ago. He was diagnosed with hyperparathyroidism associated with a parathyroid tumour and surgery was performed. Postoperatively, his serum calcium levels, which had once normalized, rose again. Medical treatment for hypercalcaemia failed to control the condition. A chest computed tomography showed multiple pulmonary nodules which were diagnosed as pulmonary metastases of parathyroid carcinoma. The tumour was considered to be the cause of the hypercalcaemia and volume reduction surgery was performed. Immediately after surgery, the patient presented with hypocalcaemia and required calcium correction with Calcium Gluconate Hydrate. Since then, the serum calcium level has stabilized and the patient has progressed without medical treatment. Parathyroid carcinoma is rare. This is a valuable case in which the serum calcium level was controlled by surgery. The patient also developed post-operative hypocalcaemia, which should be reported.

5.
Org Lett ; 4(3): 355-7, 2002 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-11820878

RESUMO

Galacto-type trehalose, a "C-4 epimer of trehalose", possesses a stereochemical structure around the alpha(1-1)-linkage analogous to that of the globobiosyl alpha(1-4)-linkage in Gb(2) and Gb(3) ceramides, which are known as the ligands of Shiga toxins produced by pathogenic E. coli. This paper presents evidence supporting the new idea of using a trehalosyl alpha(1-1)-linkage as a substitute for the galactobiosyl alpha(1-4)-linkage.


Assuntos
Galactose/química , Toxina Shiga/metabolismo , Trealose/metabolismo , Configuração de Carboidratos , Sequência de Carboidratos , Testes de Hemaglutinação , Ligantes , Modelos Moleculares , Toxina Shiga/química , Toxina Shiga/farmacologia , Trealose/química
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