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To investigate the role of complement C3 (C3) convertase on the strain difference for C3 protein expression in three inbred mice strains, we compared the levels of C2, C3 and C4 mRNA, as well as C3 protein and C3 convertase activity in the serum and liver tissue of FVB/N, C3H/HeN and C57BL/6N mice. The level of mRNA, inactive form (InACF) and active form (ACF) for C3 showed a regular pattern, which they were higher in the FVB/N and C57BL/6N mice than C3H/HeN mice. However, the level of C3b fragments (C3bα and β) derived from C3 protein were constantly maintained in the liver of FVB/N, C3H/HeN and C57BL/6N mice in spite of the strain difference on the transcriptional and translation level of C3. Especially, a reverse pattern of the level of mRNA, InACF and ACF for C3 was observed on the activity level of C3 convertase activity. The highest level of C3 convertase activity was measured in C3H/HeN mice, followed by C57BL/6N and FVB/N mice. In case of C3 convertase components, the level of C2 mRNA was higher in C3H/HeN mice than FVB/N and C57BL/6 N mice, while levels of C4 mRNA were higher in FVB/N and C57BL/6N mice than C3H/HeN mice. The current study results provide the first scientific evidence that C3 convertase may play complementary role to overcome the strain difference on the C3 protein expression in FVB/N, C3H/HeN and C57BL/6N mice.

BPAP is a potent enhancer substance with catecholaminergic and serotoninergic activity in the brain. It was discovered that it is also effective against certain types of experimental cancers, showing the most promising results in case of lung cancer. That is why we tested its efficacy in two different doses in a newly developed EGFR wild type mouse lung adenocarcinoma xenograft model. Experiments were conducted on FVB/N and SCID mouse strains treated with low and high dose of BPAP. Body weight, survival, and tumor volumes were recorded. Furthermore, the activity of major signaling pathways of NSCLC such as MAPK and Akt/mTOR as well as cell cycle regulation were determined. Significant inhibition of tumor growth was exerted by both doses, but the mechanism of action was different. High dose directly inhibited, whereas low dose activated the main signaling pathways. Exposure to low dose BPAP resulted in elevated activity of the mTOR pathway together with p16INK-induced cell cycle arrest, a typical feature of geroconversion, a senescent state characterized by loss of cell proliferation. Finally the events culminated in cell cycle inhibition point in case of both doses mirrored by the decrease of cyclin D1, CDK4 and PCNA. In addition, BPAP treatment had a beneficial effect on bodyweight suggesting that the compound at least in part is able to compensate the cancer-related wasting. In view of the low toxicity and confirmed antitumor effect of BPAP against experimental lung adenocarcinoma, this novel compound deserves further attention. Electronic supplementary material The online version of this article (10.1007/s12253-019-00603-6) contains supplementary material, which is available to authorized users.

Tensin2 (Tns2) is an essential component for the maintenance of glomerular basement membrane (GBM) structures. Tns2-deficient mice were previously shown to develop mild glomerular injury on a DBA/2 background, but not on a C57BL/6J or a 129/SvJ background, suggesting that glomerular injury by the deletion of Tns2 was strongly dependent on the genetic background. To further understand the mechanisms for the onset and the progression of glomerular injury by the deletion of Tns2, we generated Tns2-deficient mice on an FVB/N (FVB) strain, which is highly sensitive to glomerular disease. Tns2-deficient mice on FVB (FVBGN) developed severe nephrotic syndrome, and female FVBGN mice died within 8 weeks. Ultrastructural analysis revealed that FVBGN mice exhibited severe glomerular defects with mesangial process invasion of glomerular capillary tufts, lamination and thickening of the GBM and subsequent podocyte foot process effacement soon after birth. Aberrant laminin components containing α1, α2 and β1 chains, which are normally expressed in the mesangium, accumulated in the GBM of FVBGN, suggesting that these components originated from mesangial cells that invaded glomerular capillary tufts. Compared to Tns2-deficient mice on the other backgrounds in previous reports, FVBGN mice developed earlier onset of glomerular defects and rapid progression of renal failure. Thus, this study further extended our understanding of the possible genetic background effect on the deterioration of nephrotic syndrome by Tns2 deficiency.

C57Bl/6J mice are the gold standard animal model of diet‐induced obesity. These animals become obese with higher adiposity, blood fasting glucose, triglycerides, and total cholesterol when fed a high‐fat diet (HFD). Conversely, the FVB/N mouse line is thought to be resistant to diet‐induced obesity, with low or no weight gain and adiposity in response to a HFD. In this study, we investigated whether FVB/N mice are resistant or susceptible to metabolic disorder that is promoted by a HFD. Biometric parameters and blood chemistry were analyzed in C57Bl/6J and FVB/N mice that were fed a chow diet or HFD. Glucose and insulin sensitivity were assessed by performing the glucose tolerance test and measuring serum insulin/glucose and homeostasis model assessment‐insulin resistance. Metabolism‐related gene expression was investigated by real‐time reverse transcription polymerase chain reaction. Adipocyte morphology and liver steatosis were evaluated using standard histology. FVB/N mice had higher adiposity than C57Bl/6J mice that were fed a chow diet and were glucose intolerant. FVB/N mice that were fed a HFD presented higher insulin resistance and greater liver steatosis. Epididymal white adipose tissue exhibited severe inflammation in FVB/N mice that were fed a HFD. The FVB/N mouse strain is suitable for studies of diet‐induced obesity, and the apparent lack of a HFD‐induced response may reveal several strain‐specific events that are triggered by a HFD. Further studies of the FVB/N background may shed light on the complex multifactorial symptoms of obesity and metabolic syndrome.