Journal Article A Complex Noncoordinate Regulation of α-Lactalbumin and 25 K β-Casein by Corticosterone, Prolactin, and Insulin in Long Term Cultures of Normal Rat Mammary Cells Get access DURWOOD B. RAY, DURWOOD B. RAY 1Departments of Medicine, Case Western Reserve University Cleveland, Ohio 44106; Departments of Biochemistry, Case Western Reserve University Cleveland, Ohio 44106; The Veterans Administration Medical Center Cleveland, Ohio 44106 Search for other works by this author on: Oxford Academic Google Scholar ROBERT W. JANSEN, ROBERT W. JANSEN 1Departments of Medicine, Case Western Reserve University Cleveland, Ohio 44106; Departments of Biochemistry, Case Western Reserve University Cleveland, Ohio 44106; The Veterans Administration Medical Center Cleveland, Ohio 44106 Search for other works by this author on: Oxford Academic Google Scholar IRIS A. HORST, IRIS A. HORST 1Departments of Medicine, Case Western Reserve University Cleveland, Ohio 44106; Departments of Biochemistry, Case Western Reserve University Cleveland, Ohio 44106; The Veterans Administration Medical Center Cleveland, Ohio 44106 Search for other works by this author on: Oxford Academic Google Scholar NATHANIEL C. MILLS, NATHANIEL C. MILLS 1Departments of Medicine, Case Western Reserve University Cleveland, Ohio 44106; Departments of Biochemistry, Case Western Reserve University Cleveland, Ohio 44106; The Veterans Administration Medical Center Cleveland, Ohio 44106 Search for other works by this author on: Oxford Academic Google Scholar JEROME KOWAL JEROME KOWAL 1Departments of Medicine, Case Western Reserve University Cleveland, Ohio 44106; Departments of Biochemistry, Case Western Reserve University Cleveland, Ohio 44106; The Veterans Administration Medical Center Cleveland, Ohio 44106 Search for other works by this author on: Oxford Academic Google Scholar Endocrinology, Volume 118, Issue 1, 1 January 1986, Pages 393–407, https://doi.org/10.1210/endo-118-1-393 Published: 01 January 1986 Article history Received: 09 April 1984 Published: 01 January 1986
Signaling pathways involved in hepatic insulin resistance that develops in animal models of non‐alcoholic steatohepatitis (NASH) have not been adequately investigated. In this study hepatic insulin resistance was investigated in livers of C57BL/6J mice by determining protein and gene expressions of insulin receptor (IR), insulin receptor substrate (IRS), Akt and their phosphorylated forms (p‐IR, p‐IRS, and p‐Akt). Forty C57BL/6J mice, divided into control and high‐fat groups were fed low‐fat diet or HFD ad libitum for 20 weeks. At the end of 20 weeks animals were sacrificed and assays were performed for blood biomarkers typical of human NASH. As reported earlier, HFD led to increased triglyceride accumulation in the liver and induced histopathological features of human NASH including hepatic steatosis, ballooning, inflammation and fibrosis. At the end of 20 weeks, ratio of p‐IR/IR, p‐IRS/IRS, and p‐Akt/Akt expressions were significantly lower in the HF group than controls along with decreased expression's of total and phosphorylated forms. Significant reductions in the gene expressions of IR, IRS‐2, Akt and their phosphorylated forms were observed in the HF group compared to controls. Thus, hepatic insulin resistance in this NASH model is mediated via Akt signaling pathway. Supported by Research Enhancement Program, TWU and Texas Department of Agriculture
The volume explores 1930s African American writing to examine Black life, culture, and politics to document the ways Black artists and everyday people managed the Great Depression's economic impact on the creative and the social. Essays engage iconic figures such as Sterling Brown, Langston Hughes, Zora Neale Hurston, Dorothy West, and Richard Wright as well as understudied writers such as Arna Bontemps and Marita Bonner, Henry Lee Moon, and Roi Ottley. This book demonstrates the significance of the New Deal's Works Progress Administration (WPA), the Communist Party of the United States (CPUSA) and Black literary circles in the absence of white patronage. By featuring novels, poetry, short fiction, and drama alongside guidebooks, photographs, and print culture, African American Literature in Transition 1930-1940 provides evidence of the literary culture created by Black writers and readers during a period of economic precarity, expanded activism for social justice, and urgent internationalism.
The condition of non‐alcoholic steatohepatitis (NASH) presents a progressive pathology leading to steatotic fibrosis and potentially hepatic cancer. Polyphenols in grape seed extract (GSE) and fat soluble vitamin E (ä tocotrienol, ä3T) may play a beneficial role in hepatic fibrosis. In this study we examined the effects of dietary GSE and ä3T in C57BL/6J mice fed high‐fat diet (n=8/group) for 20 weeks. Post necropsy general histology and immunohistochemical analyses were performed with alpha‐smooth muscle actin (á‐SMA) as a biomarker in liver fibrosis. Mice in the high fat diet control group (HFD‐C) had increased fat accumulation and NASH‐like histopathological features. Histological data analysis of H&E stained liver sections showed that steatosis and lipid droplets were reduced in HFD+GSE group compared to HFD‐C group. Immunohistochemical staining and analysis of photomicrographs led to observable reduction of á‐SMA in HFD+GSE supplemented group compared to HFD‐C group. Our data shows that dietary GSE and ä‐tocotrienol alone and in combination may ameliorate the NASH‐like histopathological features including fibrosis in C57BL/6J mice. Supported by Research Enhancement Program, TWU
Abstract Linear polyacrylamide has been used to increase the tensile strength and stability of low percentage acrylamide gels in the range of 2.5 to 6.0 % w/v acrylamide. This added strength allows handling and staining of the gel without the excessive difficulty which is normally incurred when working in this range. Addition of up to 0.6 % w/v of linear polyacrylamide gives no pore size reduction. While addition of linear polyacrylamide to acrylamide gels using bisacrylamide as a crosslinker has a hazy appearance, the use of diallyltartardiamide as a crosslinker gives the desired clarity without loss of large pore size and improves adherence to glass walls. A further advantage of acrylamide gel matrices is that the traditional methods of silver staining can be used for detection of DNA. Thus, adding linear polyacrylamide to an acrylamide gel using diallytartardiamide as a crosslinker allows easy use of low percentage acrylamide gels for separation and detection of DNA fragments in the range of 70 to 2500 base pairs.
The anabolic effects of testosterone on kidneys from two strains of female mice were studied over a course of 25 days. The A/J and C57BL/6J strains were selected because they carry regulatory alleles Gur a and Gur b which determine rapid and slow induction of β‐glucuronidase, respectively. (A major goal of this study was to determine whether these mouse strains have other differences in their responses to testosterone). The wet weight, dry weight and total protein content of the kidneys of both strains increased about 70% in both strains. Total RNA increased 112% and 93% in a biphasic manner in the A/J and C57BL/6J mouse strains, respectively. The steep slope during the first 5 to 7 days was attributed to a selective stimulation of RNA accumulation while the latter, less rapid, RNA increase occurred in parallel with tissue growth. The total DNA content of kidneys from testosterone treated A/J mice never increased above that of controls, indicating that hypertrophy could account for renal enlargement in this strain. By contrast, testosterone treatment produced a 24% increase in total kidney DNA in C57BL/6J mice, signifying that both hypertrophy and hyperplasia are important factors in the anabolic response of this strain. These observations indicated another difference in the androgen induced response of A/J and C57BL/6J mice. As a consequence of the testosterone stimulated increase in renal β‐glucu‐ronidase synthesis, the excretion of the lysosomal form of the enzyme into the urine increased 2200‐fold in A/J but only 57‐fold in C57BLIGJ. The total enzyme activity excretedidayimouse was only 4 times higher in A/J versus C57BLi6J with the differences reflecting the basal activity which was 10‐fold higher in C57BLIGJ mice. The basal excretion of another lysosomal enzyme, β‐galactosidase, was also several fold higher in C57BL/6J, suggesting that lysosomes in those animals are either larger or their contents are excreted at a faster rate.
The statins competitively inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase activity and consequently the synthesis of mevalonate. The use of statins is associated with insulin resistance, presumably due to the impaired differentiation and diminished glucose utilization of adipocytes. We hypothesize that mevalonate is essential to adipocyte differentiation and adipogenic gene expression. Adipo-Red assay and Oil Red O staining showed that an eight-day incubation with 0–2.5 µmol/L lovastatin dose-dependently reduced the intracellular triglyceride content of murine 3T3-F442A adipocytes. Concomitantly, lovastatin downregulated the expression of peroxisome proliferator-activated receptor γ ( Pparγ), leptin ( Lep), fatty acid binding protein 4 ( Fabp4), and adiponectin ( AdipoQ) as measured by quantitative real-time polymerase chain reaction (real-time qPCR). The expression of sterol regulatory element binding protein 1 ( Srebp-1), a transcriptional regulator of Pparγ and Lep genes, was also suppressed by lovastatin. Western-blot showed that lovastatin reduced the level of CCAAT/enhancer binding protein α (C/EBPα) while inducing a compensatory over-expression of HMG CoA reductase. The impact of lovastatin on intracellular triglyceride content and expression of the adipogenic genes was reversed by supplemental mevalonate. Mevalonate-derived metabolites have essential roles in promoting adipogenic gene expression and adipocyte differentiation.
Summary Mature male rats, γ‐irradiated in utero , were hypophysectomized. In an effort to maintain the seminiferous epithelium, some animals were treated with exogenous androgen while in other animals the seminiferous epithelium was allowed to regress without hormonal treatment. These Sertoli cell‐enriched (SCE) males were evaluated for 7 weeks following hypophysectomy. In SCE males the average initial weight of each testis was 300 mg which declined to 110 mg at 7 weeks post‐hypophysectomy. Concomitantly, seminiferous tubule diameter decreased from 130 μm to approximately 89 μm. Numerous cells were detached from the lamina propria and were observed in the centre of the tubule. Two layers of Sertoli cell nuclei were frequently observed in the regressed seminiferous tubules. Many of these nuclei appeared to be less differentiated, i.e. the nuclei were smaller with smaller nucleoli and more heterochromatin. In contrast, hypophysectomized animals treated with testosterone propionate during the last 5 weeks of the 7 week observational period, retained a tissue weight of about 270 mg/testis (a 5–10% decline in weight compared with normal untreated controls). Also, these animals had seminiferous tubule diameters of 132 μm. Finally, the Sertoli cells which comprised primarily a single layer inside the seminiferous tubules had larger nuclei with finely granulated chromatin and large nucleoli. Protein changes in SCE testes, (±) androgen, following hypophysectomy were analysed using polyacrylamide gels containing SDS. Prominent changes in the protein profile as separated by molecular weight were observed and were attributable to androgen stimulation. These changes were probably occurring in Sertoli cells since the Sertoli cell represents about 70% of the total cell population in the γ‐irradiated model. It is concluded that testosterone is responsible for major changes in mature Sertoli cells, although potential contributions of other cell types such as myoid cells and Leydig cells are considered.
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