The steroid 11 beta-hydroxylase (P450c11) enzyme is responsible for the conversion of 11-deoxycortisol to cortisol in the zona fasciculata of the adrenal cortex. Animal studies have suggested that this enzyme or a closely related isozyme is also responsible for the successive 11 beta- and 18-hydroxylation and 18-oxidation of deoxycorticosterone required for aldosterone synthesis in the zona glomerulosa. There are two distinct 11 beta-hydroxylase genes in man, CYP11B1 and CYP11B2, which are predicted to encode proteins with 93% amino acid identity. We used a sensitive assay based on the polymerase chain reaction to analyze the expression of the CYP11B1 and B2 genes. Transcripts of CYP11B1 were detected at high levels in surgical specimens of normal adrenals and also in an aldosterone-secreting adrenal tumor. Transcripts of CYP11B2 were found at low levels in normal adrenals, but at a much higher level in the aldosterone-secreting tumor. CYP11B2 mRNA levels were increased in cultured zona glomerulosa cells by physiological levels of angiotensin-II. The entire coding regions of both CYP11B1 and B2 cDNAs were cloned from the tumor mRNA. Expression of these cDNAs in cultured COS-1 cells demonstrated that the CYP11B1 product could only 11 beta-hydroxylate 11-deoxycortisol or deoxycorticosterone, whereas the CYP11B2 product could also 18-hydroxylate cortisol or corticosterone. A small amount of aldosterone was synthesized from deoxycorticosterone only in cells expressing CYP11B2 cDNA. These data demonstrate that the product of CYP11B2 is required for the final steps in the synthesis of aldosterone.

In MCs exposed to HG and in diabetic rat glomeruli, increments in 12-LO mRNA and protein are associated with changes modeling diabetic nephropathy. These findings suggest a role for the 12-LO pathway in the pathogenesis of diabetic nephropathy.

BackgroundGraphene and its derivative graphene oxide (GO) have been implicated in a wide range of anticancer effects.PurposeThe objective of this study was to systematically evaluate the toxicity and underlying mechanisms of GO on two osteosarcoma (OSA) cancer cell lines, MG-63 and K7M2 cells.MethodsMG-63 and K7M2 cells were treated by GO (0–50 µg/mL) for various time periods. Cell viability was tested by MTT and Live/Dead assays. A ROS Detection Kit based on DHE oxidative reaction was used for ROS detection. An Annexin V-FITC Apoptosis Kit was used for apoptosis detection. Dansylcadaverine (MDC) dyeing was applied for seeking unspecific autophagosomes. Western blot and Immunofluorescence analysis were used for related protein expression and location.ResultsK7M2 cells were more sensitive to GO compared with MG-63 cells. The mechanism was attributed to the different extent of the generation of reactive oxygen species (ROS). In K7M2 cells, ROS was easily stimulated and the apoptosis pathway was subsequently activated, accompanied by elevated expression of proapoptosis proteins (such as caspase-3) and decreased expression levels of antiapoptosis proteins (such as Bcl-2). A ROS inhibitor (N-acetylcysteine) could alleviate the cytotoxic effects of GO in K7M2 cells. However, the production of ROS in MG-63 cells was probably inhibited by the activation of an antioxidative factor, nuclear factor-E2-related factor-2, which translocated from the cytoplasm to the nucleus after GO treatment, while a nuclear factor-E2-related factor-2 inhibitor (ML385) significantly increased ROS production in MG-63 cells when combined with GO treatment. In addition, autophagy was simultaneously stimulated by characteristic autophagosome formation, autophagy flux, and increased the expression level of autophagy-related proteins (such as LC3I to LC3II conversion, ATG5, and ATG7).ConclusionThis paper proposes various underlying mechanisms of the anticancer effect of GO. The novel synthetic use of GO with an oxidizing agent is the key step for further potential applications in clinical OSA cancer therapy.

Metabolism reprogramming influences the severity of organ dysfunction, progression to fibrosis, and development of disease in acute kidney injury (AKI). Previously we showed that inhibition of aerobic glycolysis improved survival rates and protected septic mice from kidney injury. However, the underlying mechanisms remain unclear. In the present study, it was revealed that sepsis or lipopolysaccharide (LPS) enhanced aerobic glycolysis as evidenced by increased lactate production and upregulated mRNA expression of glycolysis-related genes in kidney tissues and human renal tubular epithelial (HK-2) cells. The aerobic glycolysis inhibitor 2-deoxy-D-glucose (2-DG) downregulated glycolysis, and improved kidney injury induced by sepsis. 2-DG treatments increased the expression of sirtuin 3 (SIRT3) and phosphorylation-AMP-activated protein kinase (p-AMPK), following promoted autophagy and attenuated apoptosis of tubular epithelial cells in septic mice and in LPS-treated HK-2 cells. However, the glycolysis metabolite lactate downregulated SIRT3 and p-AMPK expression, inhibited autophagy and enhanced apoptosis in LPS-treated HK-2 cells. Furthermore, pharmacological blockade of autophagy with 3-methyladenine (3-MA) partially abolished the protective effect of 2-DG in sepsis-induced AKI. These findings indicated that inhibition of aerobic glycolysis protected against sepsis-induced AKI by promoting autophagy via the lactate/SIRT3/AMPK pathway.