The Intersection of cerebral cholesterol metabolism and Alzheimer's disease: Mechanisms and therapeutic prospects.

Alzheimer's disease (AD) is a common neurodegenerative disease in the elderly, the exact pathogenesis of which remains incompletely understood, and effective preventive and therapeutic drugs are currently lacking. Cholesterol plays a vital role in cell membrane formation and neurotransmitter synthesis, and its abnormal metabolism is associated with the onset of AD. With the continuous advancement of imaging techniques and molecular biology methods, researchers can more accurately explore the relationship between cholesterol metabolism and AD. Elevated cholesterol levels may lead to vascular dysfunction, thereby affecting neuronal function. Additionally, abnormal cholesterol metabolism may affect the metabolism of ß-amyloid protein, thereby promoting the onset of AD. Brain cholesterol levels are regulated by multiple factors. This review aims to deepen the understanding of the subtle relationship between cholesterol homeostasis and AD, and to introduce the latest advances in cholesterol-regulating AD treatment strategies, thereby inspiring readers to contemplate deeply on this complex relationship. Although there are still many unresolved important issues regarding the risk of brain cholesterol and AD, and some studies may have opposite conclusions, further research is needed to enrich our understanding. However, these findings are expected to deepen our understanding of the pathogenesis of AD and provide important insights for the future development of AD treatment strategies targeting brain cholesterol homeostasis.

Klotho mitigates cyclosporine A (CsA)-induced epithelial-mesenchymal transition (EMT) and renal fibrosis in rats.

PURPOSE: Klotho deficiency is implicated in various kidney diseases, including renal fibrosis. The aim of this study was to investigate the effect of Klotho administration on epithelial-mesenchymal transition (EMT) and renal fibrosis induced by cyclosporine A (CsA) in rats. METHODS: CsA-induced renal fibrosis was established by oral administration of CsA (30 mg/kg) to rats on a low-salt diet for 28 days. Klotho was administered to rats by intraperitoneal injection. Renal pathological changes were evaluated by hematoxylin and eosin and Masson's trichrome staining. The EMT response was assessed by measuring the level of TGF-ß1, E-cadherin and α-SMA by immunohistochemistry and Western blot. RESULTS: Administration of CsA for 28 days induced renal damage, decreased Klotho expression and activated the EMT response (demonstrated as increased TGF-ß1 and α-SMA expression accompanied by decreased in E-cadherin expression). Treatment with Klotho significantly ameliorated pathological lesions of the kidney by modulating the expression of EMT-associated proteins in the kidney. CONCLUSIONS: Klotho inhibits CsA-induced EMT and renal fibrosis in rats. Klotho may serve as a therapeutic agent to minimize CsA-induced renal fibrosis.

Role of removing stasis and reducing heat formula in clearance of proximal ureteral calculi after ureteroscopic Ho:YAG laser lithotripsy: a prospective randomized study.

OBJECTIVE: To prospectively evaluate the efficacy of Removing Stasis and Reducing Heat Formula in accelerating calculus clearance and improving lower urinary tract symptoms of patients with proximal ureteral calculi after ureteroscopic Ho:YAG laser lithotripsy. METHODS: A total of 138 patients with proximal ureteral calculi underwent ureteroscopic Ho:YAG laser lithotripsy by a single endocrinologist. Stone size varied from 10 to 15 mm. After operation, the patients were randomly divided into three groups: the control group (group A), tamsulosin group (group B), and Removing Stasis and Reducing Heat Formula group (group C). The treatment lasted for 4 weeks or until stone clearance. The primary and secondary outcomes of the three groups at follow-up were assessed. RESULTS: Of the 131 patients available for follow-up, 44 cases were in the group A, 45 in the group B, and 42 in the group C, respectively. The stone free rate at 2 weeks in the groups B and C were significantly higher than that in the group A (95.56%, 97.62% vs. 79.55%; all P<0.05). The ureteral colic rate and mean time of fragment expulsion were significantly reduced in the groups B (4.44% and 7.86±4.99 days) and C (2.43% and 6.76±4.37 days) compared with the group A (22.73% and 11.54±9.89 days, all P<0.05). On the day of double-J ureteric stent removal, the group C differed significantly from the group A in the total International Prostate Symptom Score, irritative subscore, obstructive subscore, and quality of life score (all P<0.05). CONCLUSION: Removing Stasis and Reducing Heat Formula in the medical expulsive therapy might be an effective modality for patients with calculus in the proximal uretera after ureteroscopic Ho:YAG laser lithotripsy.

[Identification and cell phenotype transdifferentiation of adipose-derived stem cells].

OBJECTIVE: To investigate the transdifferentiation of the ADSCs to epidermal cells. METHODS: ADSCs were isolated and cultured from rat adipose tissue by digestion of enzyme. ADSCs was identified by immunocytochemistry and flow cytometry. ADSCs were divided into four groups in order to induce: the condition medium (containing 30% superior of homogenizing rat skin in 10% FBS/DMEM) group, 7 days; 10% FBS/DMEM with EGF (20 ng/ml) group, 7 days; the condition medium for 4 days and then 10% FBS/DEME instead of the condition medium for 3 days group; 10% FBS/DMEM for 7 days group (control group). Cytokeratin 19 and cytokeratin 10 expressions in ADSCs were detected by flow cytometry. RESULTS: (1) The results of immunocytochemistry showed that ADSCs were positive for CD49d and negative for CD106, CD34, CD19, CD10. The results of flow cytometry showed ADSCs were positive for CD49d and CD44. (2) The CK19 expression of ADSCs was 45.32% in the condition medium group, 26.58% in the condition medium with EGF group, 23.37% in te condition medium for 4 days and then 10% FBS/DMEM instead of the condition medium for 3 days gropu and 18.53% in control group, P <0.01. The CK10 expression of ADSCs was 43.56% in the condition medium group, 25.54% in the condition medium with EGF group, 18.20% in the condition medium for 4 days and then 10% FBS/DMEM instead of the condition medium for 3 days group and 2.46% in control group, P < 0.01. CONCLUSIONS: The superior of homogenizing rat skin can induce CK19 and CK10 expressing in ADSCs, and thereby demonstrating ADSCs can differentiate to epidermal cell phenotype in vitro.

[Expression of c-jun and c-fos oncogene in medulloblastoma and its clinical significance].

OBJECTIVE: To study the potential relationship between the expressions of c-jun and c-fos oncogenes and the prognosis of medulloblastoma. METHODS: The specimens from 70 cases of medulloblastoma of the posterior fossa and 10 cases of normal cerebellar tissues were collected to determine c-jun and c-fos expressions by immunohistochemical staining in formalin fixed paraffin-embedded sections. RESULTS: (1) It showed that c-fos and c-jun protein expression was negative in 10 normal cerebellar tissue, while positive c-fos, c-jun immunoreactivity was found in 70 medulloblastoma specimens. The positive rate of c-jun and c-fos was 80% and 77%, respectively. There was high expression of c-jun and c-fos protein in medulloblastoma tissues. (2) There were positive correlations and strong co-operativity between c-jun and c-fos expression (r = 0.493, P < 0.01). (3) Correlative analysis indicated that expression of c-jun, c-fos were significantly correlated with survival time (c-jun: r = -0.447, P < 0.01; c-fos: r = -0.590, P < 0.01). The higher the expression level of c-jun and c-fos protein was, the worse the prognosis was in medulloblastoma patients. CONCLUSIONS: High expression of c-jun and c-fos protein could be noted in medulloblastoma tissues. The two transcription factors show positive correlation and strong co-existence between c-jun and c-fos expressions. The expression levels of c-jun as well as c-fos are negatively correlated with the mortality rate and life expectancy of patients with medulloblastoma. In addition, the co-expression of c-jun and c-fos could serve as an indicator for judging the prognosis of medulloblastoma.