Quantifying Mitochondrial Dynamics in Patient Fibroblasts with Multiple Developmental Defects and Mitochondrial Disorders.

Mitochondria are dynamic organelles that undergo rounds of fission and fusion and exhibit a wide range of morphologies that contribute to the regulation of different signaling pathways and various cellular functions. It is important to understand the differences between mitochondrial structure in health and disease so that therapies can be developed to maintain the homeostatic balance of mitochondrial dynamics. Mitochondrial disorders are multisystemic and characterized by complex and variable clinical pathologies. The dynamics of mitochondria in mitochondrial disorders is thus worthy of investigation. Therefore, in this study, we performed a comprehensive analysis of mitochondrial dynamics in ten patient-derived fibroblasts containing different mutations and deletions associated with various mitochondrial disorders. Our results suggest that the most predominant morphological signature for mitochondria in the diseased state is fragmentation, with eight out of the ten cell lines exhibiting characteristics consistent with fragmented mitochondria. To our knowledge, this is the first comprehensive study that quantifies mitochondrial dynamics in cell lines with a wide array of developmental and mitochondrial disorders. A more thorough analysis of the correlations between mitochondrial dynamics, mitochondrial genome perturbations, and bioenergetic dysfunction will aid in identifying unique morphological signatures of various mitochondrial disorders in the future.

Is the Neurological Disorders Depression Inventory-Epilepsy for Youth (NDDI-E-Y) more sensitive than a neurologist? A quality improvement project.

PURPOSE: Depression is one of the most prevalent psychiatric comorbidities in epilepsy. This quality improvement project compared a standardized rating scale, the Neurological Disorders Depression Inventory-Epilepsy for Youth (NDDI-E-Y), with physician opinion to see if it improved sensitivity to depressive symptoms. RESULTS: A convenience sample of thirty adolescents with epilepsy ages 12-17 (mean [M] = 15.02, standard deviation [SD] = 1.81; 53% female) participated in the screening. Thirteen percent of the sample scored in the Elevated range on the NDDI-E-Y (exceeded cutoff). Seven percent of the sample were rated by the physician as definitely showing signs of depression. There were two false negatives when the NDDI-E-Y score exceeded the established cutoff, but physician rating was negative for depressive symptoms. CONCLUSION: This pilot project shows that the NDDI-E-Y is a convenient clinical tool with the potential to improve sensitivity in the detection of depressive symptoms in adolescents with epilepsy.

GHR-/- Mice are protected from obesity-related white adipose tissue inflammation.

Growth hormone (GH) excess in bovine (b)GH transgenic mice has been shown to alter white adipose tissue (WAT) immune cell populations. The present study aimed to evaluate the effects of GH resistance on WAT immune cell populations using GH receptor knockout (GHR-/- ) mice. Eight- and 24-month-old, male GHR-/- and wild-type mice were used. Body composition and tissue weights were determined, and systemic inflammation was assessed by measuring serum cytokine levels. The stromal vascular fraction (SVF) was isolated from three distinct WAT depots, and immune cell populations were quantified using flow cytometry. GHR-/- mice at both ages had decreased body weight but were obese. Although no significant changes were observed in serum levels of the measured cytokines, SVF cell alterations were seen and differed from depot to depot. Total SVF cells were decreased in epidydimal (Epi) depots, whereas SVF cells per gram adipose tissue weight were increased in mesenteric (Mes) depots of GHR-/- mice relative to controls. T cells and T helper cells were increased in Mes at 8 months old, whereas cytotoxic T cells were decreased in subcutaneous (SubQ) at 24 months old. Other cells were unchanged at both ages measured. The present study demonstrates that removal of GH action results in modest and depot-specific changes to several immune cell populations in WAT of intra-abdominal depots (Epi and Mes), which are somewhat surprising results because the SubQ has the largest change in size, whereas the Mes has no size change. Taken together with previous results from bovine GH transgenic mice, these data suggest that GH induces changes in the immune cell population of WAT in a depot-specific manner. Notably, GHR-/- mice appear to be protected from age-related WAT inflammation and immune cell infiltration despite obesity.

Growth Hormone Upregulates Mediators of Melanoma Drug Efflux and Epithelial-to-Mesenchymal Transition In Vitro and In Vivo.

Growth hormone (GH) and the GH receptor (GHR) are expressed in a wide range of malignant tumors including melanoma. However, the effect of GH/insulin-like growth factor (IGF) on melanoma in vivo has not yet been elucidated. Here we assessed the physical and molecular effects of GH on mouse melanoma B16-F10 and human melanoma SK-MEL-30 cells in vitro. We then corroborated these observations with syngeneic B16-F10 tumors in two mouse lines with different levels of GH/IGF: bovine GH transgenic mice (bGH; high GH, high IGF-1) and GHR gene-disrupted or knockout mice (GHRKO; high GH, low IGF-1). In vitro, GH treatment enhanced mouse and human melanoma cell growth, drug retention and cell invasion. While the in vivo tumor size was unaffected in both bGH and GHRKO mouse lines, multiple drug-efflux pumps were up regulated. This intrinsic capacity of therapy resistance appears to be GH dependent. Additionally, epithelial-to-mesenchymal transition (EMT) gene transcription markers were significantly upregulated in vivo supporting our current and recent in vitro observations. These syngeneic mouse melanoma models of differential GH/IGF action can be valuable tools in screening for therapeutic options where lowering GH/IGF-1 action is important.

Impact of Growth Hormone on Regulation of Adipose Tissue.

Increasing prevalence of obesity and obesity-related conditions worldwide has necessitated a more thorough understanding of adipose tissue (AT) and expanded the scope of research in this field. AT is now understood to be far more complex and dynamic than previously thought, which has also fueled research to reevaluate how hormones, such as growth hormone (GH), alter the tissue. In this review, we will introduce properties of AT important for understanding how GH alters the tissue, such as anatomical location of depots and adipokine output. We will provide an overview of GH structure and function and define several human conditions and cognate mouse lines with extremes in GH action that have helped shape our understanding of GH and AT. A detailed discussion of the GH/AT relationship will be included that addresses adipokine production, immune cell populations, lipid metabolism, senescence, differentiation, and fibrosis, as well as brown AT and beiging of white AT. A brief overview of how GH levels are altered in an obese state, and the efficacy of GH as a therapeutic option to manage obesity will be given. As we will reveal, the effects of GH on AT are numerous, dynamic and depot-dependent. © 2017 American Physiological Society. Compr Physiol 7:819-840, 2017.

Developments in our understanding of the effects of growth hormone on white adipose tissue from mice: implications to the clinic.

Adipose tissue (AT) is a well-established target of growth hormone (GH) and is altered in clinical conditions associated with excess, deficiency and absence of GH action. Due to the difficulty in collecting AT from clinical populations, genetically modified mice have been useful in better understanding how GH affects this tissue. Recent findings in mice would suggest that the impact of GH on AT is beyond alterations of lipolysis, lipogenesis or proliferation/ differentiation. AT depot-specific alterations in immune cells, extracellular matrix, adipokines, and senescence indicate an expanded role for GH in AT physiology. This mouse data will guide additional studies necessary to evaluate the therapeutic potential and safety of GH for conditions associated with altering AT, such as obesity. In this review, we introduce several relatively new intricacies of GH's effect on AT, focusing on recent studies in mice. Finally, we summarize the clinical implications of these findings.

Fibroblast growth factor 21, fibroblast growth factor receptor 1, and ß-Klotho expression in bovine growth hormone transgenic and growth hormone receptor knockout mice.

OBJECTIVE: Although growth hormone (GH) and fibroblast growth factor 21 (FGF21) have a reported relationship, FGF21 and its receptor, fibroblast growth factor receptor 1 (FGFR1) and cofactor ß-Klotho (KLB), have not been analyzed in chronic states of altered GH action. The objective of this study was to quantify circulating FGF21 and tissue specific expression of Fgf21, Fgfr1, and Klb in mice with modified GH action. Based on previous studies, we hypothesized that bovine GH transgenic (bGH) mice will be FGF21 resistant and GH receptor knockout (GHR-/-) mice will have normal FGF21 action. DESIGN: Seven-month-old male bGH mice (n=9) and wild type (WT) controls (n=10), and GHR-/- mice (n=8) and WT controls (n=8) were used for all measurements. Body composition was determined before dissection, and tissue weights were measured at the time of dissection. Serum FGF21 levels were evaluated by ELISA. Expression of Fgf21, Fgfr1, and Klb mRNA in white adipose tissue (AT), brown AT, and liver were evaluated by reverse transcription quantitative PCR. RESULTS: As expected, bGH mice had increased body weight (p=3.70E-8) but decreased percent fat mass (p=4.87E-4). Likewise, GHR-/- mice had decreased body weight (p=1.78E-10) but increased percent fat mass (p=1.52E-9), due to increased size of the subcutaneous AT depot when normalized to body weight (p=1.60E-10). Serum FGF21 levels were significantly elevated in bGH mice (p=0.041) and unchanged in GHR-/- mice (p=0.88). Expression of Fgf21, Fgfr1, and Klb mRNA in white AT and liver were downregulated or unchanged in both bGH and GHR-/- mice. The only exception was Fgf21 expression in brown AT of GHR-/-, which trended toward increased expression (p=0.075). CONCLUSIONS: In accordance with our hypothesis, we provide evidence that circulating FGF21 is increased in bGH animals, but remains unchanged in GHR-/- mice. Downregulation or no change in Fgf21, Fgfr1, and Klb expression are seen in white AT, brown AT, and liver of bGH and GHR-/- mice when compared to their respective controls, except for an increase in brown AT Fgf21 expression in GHR-/- mice, which could suggest a possible link to increased thermogenic potential in these mice. Overall, these results suggest possible modulation of FGF21 by GH resulting in FGF21 resistance or changes in FGF21 levels due to GH induced changes in liver size or kidney function.