Loss of Von Hippel–Lindau (VHL) Tumor Suppressor Gene Function: VHL–HIF Pathway and Advances in Treatments for Metastatic Renal Cell Carcinoma (RCC)

Renal cell carcinoma (RCC) is a malignancy of the kidney originating from the tubular epithelium. Inactivation of the von Hippel–Lindau tumor-suppressor gene (VHL) is found in most clear cell renal cell carcinomas (ccRCCs). The VHL–HIF–VEGF/VEGFR pathway, which involves the von Hippel–Lindau tumor suppressor protein (VHL), hypoxia-inducible factor (HIF), vascular endothelial growth factor (VEGF), and its receptor (VEGFR), is a well-studied therapeutic target for metastatic ccRCC. Therefore, over the past decade, anti-angiogenic agents targeting VEGFR have served as the standard treatment for metastatic RCC. Recently, based on the immunomodulatory effect of anti-VEGFR therapy, anti-angiogenic agents and immune checkpoint inhibitor combination strategies have also emerged as therapeutic strategies. These advances were made possible by the improved understanding of the VHL–HIF pathway. In this review, we summarize the historical evolution of ccRCC treatments, with a focus on the involvement of the VHL–HIF pathway.     

超滤对芸豆蛋白酶解物抗氧化活性的影响

采用超滤法从芸豆蛋白酶解物中初步分离纯化抗氧化活性肽。研究超滤系统主要参数对膜通量的影响,确定最优的超滤条件和膜清洗方法,并对超滤前后酶解物的相对分子质量分布、氨基酸组成及抗氧化活性进行比较。结果表明：采用改性聚醚砜平板超滤膜在室温,酶解液质量分数2.5%,pH6.5 和压力0.25MPa 条件下的分离纯化效果较好;超滤能有效去除酶解液中相对分子质量较大的组分,相对分子质量2000～1000D 及1000D 以下的组分分别从11.38% 和12.64% 提高到32.83% 和 45.91%,其抗氧化活性也得到明显提高。     

Isolation of stem cells from adult rat kidneys

The kidney has an inherent ability for recovery and regeneration following acute damage. However, there has been much contention as to the source of regenerating renal cells. The aim of this study was to isolate and characterize these cells. Normal rat kidneys were minced and cells were isolated with collagenase I and were cultured in an expansion medium. Adherent cells were isolated and expanded for more than 120 days in vitro. These cells had the potential of trans-lineage differentiation into neural cells, adipocytes and osteocytes. These cells also expressed Nucleostemin, Cyclin D1, Notch1 and Survivin which are commonly expressed in stem cells. The results of the current work show that the adult kidney contains a population of multipotent stem cells.     

芸豆芽菜多酚对D-半乳糖致小鼠机体氧化及肾脏损伤的修复作用

为探究芸豆芽菜多酚对D-半乳糖致小鼠机体氧化及肾脏损伤的修复作用,通过腹腔注射D-半乳糖溶液构建小鼠损伤模型,连续灌胃不同剂量(低、中、高分别为20、40、60 mg/(kg·d)芸豆芽菜多酚及抗坏血酸(VC)28 d后,测定小鼠体质量、肾脏脏器系数、血清谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活力、超氧化物歧化酶(superoxide dismutase,SOD)活力、丙二醛(malondialdehyde,MDA)、尿素氮(blood urea nitrogen,BUN)及血肌酐(creatinine,CR)含量,并取肾脏制作苏木精-伊红染色(hematoxylineosin staining,HE)病理学组织切片,观察小鼠肾脏损伤及灌胃给药后的恢复情况。结果发现,相较于模型对照组小鼠,除芸豆芽菜多酚低剂量组外,其他灌胃给药组小鼠体质量及肾脏系数均有所升高,但组间并无显著性差异(P0.05);其他灌胃给药组小鼠血清GSH-Px活力显著上升(P0.05),MDA含量显著下降(P0.05);各灌胃给药组小鼠血清SOD活力均较模型对照组显著上升(P0.05)。各灌胃给药组(除芸豆芽菜多酚低剂量组)小鼠肾脏功能指示指标BUN及CR含量均较模型对照组小鼠显著下降(P0.05);肾脏HE病理学组织切片显示,模型对照组小鼠肾脏严重受损、肾小球及肾小球囊肿大并伴有间质渗血及炎性细胞浸润现象,灌胃给药后,各灌胃给药组小鼠肾脏肾小球及肾小球囊恢复正常形态,间质渗血及炎性细胞浸润现象减少。结合各灌胃给药组检测指标及HE病理学组织切片分析得知,芸豆芽菜多酚对小鼠机体氧化及肾脏损伤修复作用与剂量呈正相关。     

芸豆芽菜多酚对氧化损伤小鼠体内抗氧化及肝脏损伤修复作用

本实验探究了芸豆芽菜多酚对D-半乳糖造模的氧化损伤小鼠体内抗氧化及肝脏损伤修复作用。腹腔注射D-半乳糖溶液构建氧化损伤小鼠模型,经连续灌胃不同剂量(20、40、60 mg/(kg·d))芸豆芽菜多酚28 d后测定小鼠体质量、肝脏脏器系数、血清超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)、谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate transaminase,AST)活力及丙二醛(malondialdehyde,MDA)含量并取肝脏制作苏木精-伊红染色切片,观察小鼠肝脏损伤及修复状况。与模型对照组小鼠比较,各灌胃给药组小鼠体质量及肝脏脏器系数无显著性差异(P0.05),芸豆芽菜多酚中、高剂量组小鼠血清SOD、GSH-Px活力显著上升(P0.05),MDA含量显著下降(P0.05),肝脏功能指示指标ALT与AST活力显著下降(P0.05),且综合肝组织病理学染色切片结果观察发现芸豆芽菜多酚可使肿胀的肝细胞恢复正常形态,并可减少胞间出血点及炎性细胞浸润现象,且作用效果与剂量呈正相关。     

鸡枞菌精多糖对酒精性损伤小鼠肾及免疫器官的抗氧化作用

目的：研究鸡枞菌精多糖（refined polysaccharide from Termitomyces albuminosus,RTAP）对酒精所致急性肝损伤小鼠肾、脾脏及胸腺的保护作用。方法：采用超声波辅助的热水浸提法提取鸡枞菌多糖,小鼠被随机分为正常组、模型组、阳性对照组（饲喂联苯双酯,150 mg/（kg·d））、RTAP各剂量组（100、200、400 mg/（kg·d））,连续灌胃30 d,正常组按等量生理盐水灌胃。第31天除了正常组外,给予50%乙醇（12 mL/kg）建立动物急性肝损伤模型。小鼠处死后取肾脏、脾脏、胸腺,测定各项抗氧化指标。结果：与模型组相比,RTAP各剂量组均能降低肾脏、脾脏及胸腺丙二醛含量,提高各器官超氧化物歧化酶活性、过氧化氢酶活性、谷胱甘肽过氧化物酶活性及谷胱甘肽含量。结论：RTAP对酒精性损伤小鼠肾及免疫器官具有明显的抗氧化作用,其原理应该与其所具有抗脂质过氧化和清除体内过多的氧自由基作用有关。     

二维液相色谱-质谱法研究犬肾小管上皮细胞脂质组成及马兜铃酸(Ⅰ)对其影响

采用在线正反相二维液相色谱-质谱联用技术研究了犬肾小管上皮细胞脂质组成及马兜铃酸(Ⅰ)对其影响。二维色谱的第一维用于分离不同种类脂质,第二维用于分离同类脂质的不同分子,进而利用高分辨质谱对脂质分子进行检测。该方法减少了共流出,降低了电离抑制,提高了灵敏度与准确性。借助精确质荷比检索数据库、高分辨二级质谱和当量碳数与保留时间规律等方法检测了犬肾小管上皮细胞中13类脂质的1 416个脂质分子。选取11种外源性脂质标准品进行方法验证,方法的线性关系、检测限、重复性均满足检测要求。在此基础上,考察了犬肾小管上皮细胞暴露于马兜铃酸(Ⅰ)后的脂质变化情况,对改变含量2～4倍的15个脂质分子进行了鉴定。该实验结果可为马兜铃酸的毒理、病理研究和相关疾病的临床诊断提供丰富的信息,并展现了二维液相色谱 质谱法在脂质组学研究中广阔的应用前景。     

芸豆肽的抗氧化活性研究

采用Sephadex-G50 凝胶柱层析分离具有强抗氧化活性的小分子芸豆肽,以VC 为对照,研究3 种肽分离组分的还原能力及对羟自由基、超氧阴离子自由基和DPPH 自由基的清除能力。结果表明：随着相对分子质量的减小和肽质量浓度的增加,其还原能力及对羟自由基、超氧阴离子自由基和DPPH 自由基的清除能力逐渐增大;小分子芸豆肽(C 组分)的还原能力低于VC;对羟自由基、超氧阴离子自由基和DPPH 自由基的半清除质量浓度分别为2.301、2.553、1.386mg/mL。该小分子肽组分的相对分子质量主要集中在100～1000,该组分疏水性氨基酸含量为36.78%,其疏水值达到364.73 kcal/mol。说明小分子肽组分的抗氧化活性与其氨基酸种类和组成、相对分子质量分布密切相关。     

A Sodium Oxalate-Rich Diet Induces Chronic Kidney Disease and Cardiac Dysfunction in Rats

Chronic kidney disease (CKD) is a worldwide public health issue affecting 14% of the general population. However, research focusing on CKD mechanisms/treatment is limited because of a lack of animal models recapitulating the disease physiopathology, including its complications. We analyzed the effects of a three-week diet rich in sodium oxalate (OXA diet) on rats and showed that, compared to controls, rats developed a stable CKD with a 60% reduction in glomerular filtration rate, elevated blood urea levels and proteinuria. Histological analyses revealed massive cortical disorganization, tubular atrophy and fibrosis. Males and females were sensitive to the OXA diet, but decreasing the diet period to one week led to GFR significance but not stable diminution. Rats treated with the OXA diet also displayed classical CKD complications such as elevated blood pressure and reduced hematocrit. Functional cardiac analyses revealed that the OXA diet triggered significant cardiac dysfunction. Altogether, our results showed the feasibility of using a convenient and non-invasive strategy to induce CKD and its classical systemic complications in rats. This model, which avoids kidney mass loss or acute toxicity, has strong potential for research into CKD mechanisms and novel therapies, which could protect and postpone the use of dialysis or transplantation.     

Molecular Biological and Clinical Understanding of the Pathophysiology and Treatments of Hyperuricemia and Its Association with Metabolic Syndrome,Cardiovascular Diseases and Chronic Kidney Disease

Uric acid (UA) is synthesized mainly in the liver, intestines, and vascular endothelium as the end product of an exogenous purine from food and endogenously from damaged, dying, and dead cells. The kidney plays a dominant role in UA excretion, and the kidney excretes approximately 70% of daily produced UA; the remaining 30% of UA is excreted from the intestine. When UA production exceeds UA excretion, hyperuricemia occurs. Hyperuricemia is significantly associated with the development and severity of the metabolic syndrome. The increased urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) expression, and glycolytic disturbances due to insulin resistance may be associated with the development of hyperuricemia in metabolic syndrome. Hyperuricemia was previously thought to be simply the cause of gout and gouty arthritis. Further, the hyperuricemia observed in patients with renal diseases was considered to be caused by UA underexcretion due to renal failure, and was not considered as an aggressive treatment target. The evidences obtained by basic science suggests a pathogenic role of hyperuricemia in the development of chronic kidney disease (CKD) and cardiovascular diseases (CVD), by inducing inflammation, endothelial dysfunction, proliferation of vascular smooth muscle cells, and activation of the renin-angiotensin system. Further, clinical evidences suggest that hyperuricemia is associated with the development of CVD and CKD. Further, accumulated data suggested that the UA-lowering treatments slower the progression of such diseases.