Cholesterol Perturbation in Mice Results in p53 Degradation and Axonal Pathology through p38 MAPK and Mdm2 Activation

Perturbation of lipid metabolism, especially of cholesterol homeostasis, can be catastrophic to mammalian brain, as it has the highest level of cholesterol in the body. This notion is best illustrated by the severe progressive neurodegeneration in Niemann-Pick Type C (NPC) disease, one of the lysosomal storage diseases, caused by mutations in the NPC1 or NPC2 gene. In this study, we found that growth cone collapse induced by genetic or pharmacological disruption of cholesterol egress from late endosomes/lysosomes was directly related to a decrease in axonal and growth cone levels of the phosphorylated form of the tumor suppressor factor p53. Cholesterol perturbation-induced growth cone collapse and decrease in phosphorylated p53 were reduced by inhibition of p38 mitogen-activated protein kinase (MAPK) and murine double minute (Mdm2) E3 ligase. Growth cone collapse induced by genetic (npc1−/−) or pharmacological modification of cholesterol metabolism was Rho kinase (ROCK)-dependent and associated with increased RhoA protein synthesis; both processes were significantly reduced by P38 MAPK or Mdm2 inhibition. Finally, in vivo ROCK inhibition significantly increased phosphorylated p53 levels and neurofilaments in axons, and axonal bundle size in npc1−/− mice. These results indicate that NPC-related and cholesterol perturbation-induced axonal pathology is associated with an abnormal signaling pathway consisting in p38 MAPK activation leading to Mdm2-mediated p53 degradation, followed by ROCK activation. These results also suggest new targets for pharmacological treatment of NPC disease and other diseases associated with disruption of cholesterol metabolism

Intrahepatic Cholangiocarcinoma Skin Metastasis in a Patient with Hidradenitis Suppurativa: A Rare Entity

We present a challenging diagnosis of disseminated intrahepatic cholangiocarcinoma presenting with perineal cutaneous masses in a young African American male with known hidradenitis suppurativa. The patient was a 39-year-old male who presented to the emergency department with difficulty walking due to severe gluteal swelling and pain. The patient had an 18-month history of biopsy-proven hidradenitis suppurativa. Examination under anesthesia disclosed a 9×6 cm left perianal mass and right 5×3 cm right peri-scrotal mass; both masses were excised and revealed adenocarcinoma with signet ring cell differentiation. The patient was diagnosed with widely metastatic adenocarcinoma of unknown primary. Initiation of palliative capecitabine was planned however the patient decompensated and expired one month from the time of his diagnosis due to septic shock. Autopsy with histologic staining revealed innumerable liver lesions consistent with rare variant Intrahepatic Cholangiocarcinoma (ICC) with signet-ring cell differentiation. Multiple red papules were noted on the aortic valve with histology similarly demonstrating signet-ring cell adenocarcinoma. Cutaneous metastasis of cholangiocarcinoma has been reported but is rare, and to our knowledge this is the first reported case of cholangiocarcinoma cutaneous metastasis in a patient with hidradenitis suppurativa. This case re-emphasizes the protean presentation and aggressive metastatic potential of ICC. It also highlights the importance of maintaining a wide differential for dermatologic lesions in patients with hidradenitis suppurativa and postulates a mechanism for metastatic seeding of areas affected by this disease.</p

A survey of parasitoid species within Eriogyna pyretorum (Lepidoptera: Saturniidae) in Fuzhou Region of China

Eriogyna pyretorum Westwood is a notorious defoliator of Cinnamomum camphora (L.) J. Presl that causes large economic and ecological losses in planted forests. To understand the importance of suppress population of E. pyretorum on natural parasitoids, a two-years investigation was conducted in the field. Four parasitoid species were identified from E. pyretorum: Gregopimpla himalayensis (Cameron, 1899), Theronia depressa (Gupta, 1962), Xanthopimpla konowi (Krieger, 1899) and Kriechbaumerella longiscutellaris Qian et He. G. himalayensis and T. depressa were first reported parasitoid wasps within E. pyretorum. Parasitism rates were 18.76% for K. longiscutellaris, 2.10% for G. himalayensis, 7.55% for T. depressa and 0.83% for X. konowi. Longevity, offspring and sex ratio were compared in four hymenopteran species, and K. longiscutellaris was the abundant parasitoid of E. pyretorum in Fujian province of China

Anoikis and SPP1 in idiopathic pulmonary fibrosis: integrating bioinformatics, cell, and animal studies to explore prognostic biomarkers and PI3K/AKT signaling regulation

This study aims to explore the relevance of anoikis in idiopathic pulmonary fibrosis (IPF) and identify associated biomarkers and signaling pathways. Unsupervised consensus cluster analysis was employed to categorize IPF patients into subtypes. We utilized Weighted Gene Co-Expression Network Analysis (WGCNA) and Protein-Protein Interaction network construction to identify anoikis-related modules and key genes. A prognostic signature was developed using Lasso and multivariate Cox regression analysis. Single-cell sequencing assessed hub gene expression in various cell types, and both cell and animal experiments confirmed IPF-related pathways. We identified two distinct anoikis-associated subtypes with differing prognoses. WGCNA revealed essential hub genes, with SPP1 being prominent in the anoikis-related signature. The anoikis-related signature is effective in determining the prognosis of patients with IPF. Single-cell sequencing highlighted significant differences in SPP1 expression, notably elevated in fibroblasts derived from IPF patients. In vivo and in vitro experiments demonstrated that SPP1 enhances fibrosis in mouse lung fibroblasts by regulating p27 through the PI3K/Akt pathway. Our research demonstrates a robust prognostic signature associated with anoikis and highlights SPP1 as a pivotal regulator of the PI3K/AKT signaling pathway in pulmonary fibrosis.</p