Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002736 (amyotrophic lateral sclerosis)
 19,048 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Insulin-like growth factors (IGF-I and IGF-II) and fibroblast growth factors [acidic FGF (aFGF) and basic FGF (bFGF)] are trophic for motor neurones in vitro and (in laboratory animals) in vivo. An immunohistochemical investigation was performed on the distribution of these factors in the neuromuscular system of control patients and patients with amyotrophic lateral sclerosis (ALS). Comparisons were made with rat tissue. IGF-I immunoreactivity (IGF-I-IR) was seen in motor neurone cell bodies and axons, astroglia and Schwann cells, and in muscle fibres. IGF-II-IR was weak in all these cells. aFGF-IR was present in motor neurone cell bodies and axons, oligodendroglia and muscle fibres, but was not demonstrable in Schwann cells. bFGF-IR was present in motor neurone cell bodies and axons, and in astroglia, but was not seen in Schwann cells or muscle fibres. The distribution of the IGFs and FGFs in material from motor neurone disease (MND) and controls was similar. A role for any of these factors in the etiology of MND is, therefore, unlikely. IGF-I-IR and aFGF-IR were stronger in type II than in type I muscle fibres and were increased in denervated fibres. Species differences were found for IGF-I and bFGF. The function of these factors is apparently not entirely similar in humans and rats.
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PMID:Insulin-like and fibroblast growth factors in spinal cords, nerve roots and skeletal muscle of human controls and patients with amyotrophic lateral sclerosis. 801 77

The survival and functional maintenance of spinal motoneurones and of peripheral neurones, such as sensory, sympathetic and parasympathetic neurones, has been shown to depend on neurotrophic factors, both during the period of developmental cell death and in adulthood. A variety of such factors has been identified over recent years, among them factors of the NGF gene family, for example BDNF, NT-3, NT-4/5 and NT-6, and factors such as CNTF and LIF acting on neuronal target cells via receptor components shared with cytokines such as IL-6. In addition, pluripotent mitogens, such as IGF-I and IGF-II can support the survival of a variety of neuronal cell types, including spinal motoneurones both in cell culture and in vivo. The establishment of mice in which the genes for these factors and their receptors have been inactivated by homologous recombination has been a major step in the understanding of their physiological function. It is not clear so far whether or not similar gene defects in human are associated with any neurological disease. However, some of these factors have been demonstrated to be effective in animal models of neuropathy and motoneurone disorders, so that first clinical trials using these factors for symptomatic treatment of amyotrophic lateral sclerosis (ALS) and peripheral neuropathies have already been initiated.
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PMID:Molecular biology of neurotrophic factors. 859 25

The structurally related peptides, insulin and insulin-like growth factors (IGF-I and IGF-II), have neurotrophic properties and potentially could be of therapeutic value in human neurodegenerative disorders. In this study, we compared the anatomical distribution of [125I]IGF-I, [125I]IGF-II and [125I]insulin binding sites in thoracic spinal cords from patients who died of amyotrophic lateral sclerosis (ALS) and normal controls. For these three ligands, the greatest amounts of specific binding were located in the deeper layers of the dorsal horn > intermediate zone > lamina X > ventral horn > superficial layers of the dorsal horn > white matter of the spinal cord. Highly significant (P < 0.001) increases in the density of [125I]IGF-I and [125I]IGF-II binding were apparent in various laminae of the cord of ALS patients with increased binding being particularly evident in the ventral horn and the intermediate zone. Significant (P < 0.05) increases were also seen in lamina X and in the dorsal horn. In contrast, no significant differences in [125I]insulin binding were observed between ALS and control spinal cords. Taken together, these data reveal significant increases in both [125I]IGF-I and [125I]IGF-II binding levels in the spinal cords of ALS patients albeit to different extents. These findings may be of relevance for future therapeutic strategies aimed at slowing the progression of this chronic neurodegenerative disease, as recently suggested by the beneficial therapeutic effects of an IGF-I treatment in ALS patients.
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PMID:Distribution and levels of insulin-like growth factor (IGF-I and IGF-II) and insulin receptor binding sites in the spinal cords of amyotrophic lateral sclerosis (ALS) patients. 888 43

Among the well defined insulin-like growth factor (IGF)-binding proteins (IGFBPs), IGFBP-3 is characterized by its interaction with an acid-labile glycoprotein (ALS) in the presence of IGFs. To identify the structural determinants on IGFBP-3 required for ligand binding and cell association, five recombinant human IGFBP-3 variants were expressed in Chinese hamster ovary cells: deletions of amino acids 89-264, 89-184, and 185-264, and site-specific mutations 228KGRKR --> MDGEA and 253KED --> RGD. The basic carboxyl-terminal region of IGFBP-3 was required for binding to heparin. The deletion variants had greatly decreased IGF binding ability as assessed by ligand blotting and solution binding assays; affinity cross-linking indicated at least a 20-fold decrease in IGF affinity. The RGD mutant had a 4-6-fold reduced affinity for both IGFs, but the MDGEA mutant bound IGF-I with near normal affinity and IGF-II with a 3-fold reduction in affinity. The three deletion variants were incapable of binding ALS; but of the site-specific variants, the MDGEA mutant bound ALS with 90% lower affinity (Ka = 2.5 +/- 0.9 liters/nmol) than seen for rhIGFBP-3 (Ka = 24.3 +/- 5.2 liters/nmol), whereas the RGD mutation had no effect on ALS affinity (Ka = 21.7 +/- 4.5 liters/nmol). The ability of IGFBP-3 to associate with the cell surface was lost in variants lacking residues 185-264 and in the 228KGRKR --> MDGEA mutant. We conclude that residues 228-232 of IGFBP-3 are essential for cell association and are required for normal ALS binding affinity.
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PMID:Structural determinants of ligand and cell surface binding of insulin-like growth factor-binding protein-3. 944 66

Insulin-like growth factors (IGFs) and IGF binding proteins (IGFBPs) play an important role in cell growth and differentiation. Clinical and epidemiological studies have indicated that measuring IGFs and IGFBPs in blood has potential implications in assessing growth-related abnormalities and risks of certain types of cancer. To facilitate the application, we reported a large collection of reference ranges of IGFs and IGFBPs in normal population and evaluations of these molecules in serum and plasma as well as the impact of freeze-thaw cycles on the measurement. IGF-I, IGFBP-3 andALS showed a similar pattern of change associated with age. Levels of these molecules were low at birth and increased with age through puberty. After puberty the levels declined slowly with age. Overall, IGF-I, IGFBP-3 and ALS were slightly higher in females than in males. Free IGF-I accounted for about 1% of the total IGF-I and its variation with age was similar to total IGF-I. IGF-II levels were also increased with age from birth to puberty, but became stable after puberty. There was little difference in IGF-II levels between genders. IGFBP-2 levels declined with age from birth to puberty. Levels of IGFBP-6 in contrast were increased with age. These IGF binding proteins were higher in males than in females. IGFs, IGFBP-3 and ALS were 5-10% higher in serum than in plasma. IGFBP-2 and IGFBP-6 differed substantially between serum and plasma. Freeze-thaw treatment up to five cycles had little impact on plasma levels of IGFs and IGFBP-3. Our observations suggest that levels of IGFs and their binding proteins are varied with age, gender, and types of specimen and that these variations need to be taken into consideration when IGFs and their binding proteins are utilized in clinic and research.
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PMID:Insulin-like growth factors (IGF-I, free IGF-I and IGF-II) and insulin-like growth factor binding proteins (IGFBP-2, IGFBP-3, IGFBP-6, and ALS) in blood circulation. 1041 96

IGF-I and IGF-II (IGFs) form higher molecular weight complexes with specific binding proteins (IGFBP-1 to -6). These complexes are referred to as binary complexes consisting of IGF-I or IGF-II and one IGFBP, or as ternary complexes each consisting of either of IGF-I or IGF-II, IGFBP-3 or -5, and an acid-labile subunit known as ALS. Ternary complex formation restricts the IGFs to the circulation and prolongs their half-life. Recently, the development of an animal model for ALS deficiency (the ALS-KO mouse) and the identification of a patient with an inactivating mutation in the IGFALS gene have provided the opportunity to assess the physiological role of this protein in the circulating IGF system. ALS deficiency has no effect on fetal growth in both the ALS-KO mice and the ALS-deficient patients. A modest reduction in post-natal growth in the null ALS mice and in the ALS-deficient patients was observed. The plasma concentrations of IGF-I and IGFBP-3 were markedly reduced both in ALS-KO mice and in the ALS-deficient patients. Basal GH levels remained normal in the ALS-KO mice and moderately increased in the ALS-deficient patients. Insulin-resistance was present in the ALS-deficient patients but not in the ALS-KO mice. Reduced bone mineral density (BMD) was present in mice and human ALS deficiency. Phenotypic features of complete ALS deficiency, that are very similar in mouse and human, include: a) the inability to form ternary complex, b) the small growth impairment in spite of the marked reduction in circulating IGF-I, and c) the reduction in BMD. On the other hand, insulin resistance and pubertal delay were observed only in human ALS deficiency. These findings underlie the important physiological role of ALS in the maintenance of the circulating IGF-I reservoir. Both models will be useful in identifying the respective roles of plasma and locally derived IGF-I in regulating metabolism and growth of specific tissues.
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PMID:Acid-labile subunit deficiency: phenotypic similarities and differences between human and mouse. 1611 75

The impact of GH deficiency and rhGH replacement therapy on IGF-I, IGFBP-3 and ALS levels has been widely studied. There is less information available on IGF-II levels, the component of the ternary complex poorly dependent on GH. We investigate the components of IGFs system in 36 GHD adults (28M, 8F, age 45 +/- 14 yrs) before and after 12 months of rhGH therapy (mean dose 0.3 +/- 0.1 mg/day). One-hundred healthy sex- and age-matched subjects were studied for comparison. At baseline, GHD patients showed IGF-I and IGF-II levels and IGFs to IGFBP-3 molar ratios that were lower than controls. During therapy, IGF-I levels increased (p < 0.01) to normal range. IGF-II levels, though higher than at baseline (p < 0.01), remained lower than in controls (p < 0.01). ALS and IGFBP-3 significantly increased (p < 0.001). These modifications resulted in normalization in IGF-I to IGFBP-3 ratio, while no change in IGF-II to IGFBP-3 ratio was observed. In conclusion, the increase of serum IGF-II levels during rhGH treatment in GHD patients probably reflects the increase in the other components of ternary complex (ALS and IGFBP-3). However, serum IGF-II levels as well as IGF-II to IGFBP-3 ratio, although increased, were definitely lower than in controls. This last result, given the increasing evidences of a direct implication of IGF-II in cancer, may further confirm the safety of rhGH replacement in adults with severe GHD as diagnosed by appropriate stimulation tests.
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PMID:Evaluation of the components of the insulin-like growth factors system in GH-deficient adults: effects of twelve-month rhGH treatment. 1671 34

Amyotrophic lateral sclerosis (ALS) is a progressive degenerative disease involving the upper and lower motor neuron systems. Activated microglia are reported to enhance motor neuron death by secreting neurotoxic cytokines in SOD1-transgenic mice. Recent studies have provided evidence that chronic stimulation leads microglia to acquire an anti-inflammatory phenotype, characterized by activated morphology and induction of neuroprotective and immunoregulatory molecules. However, little information is available on the protective functions of microglia in the ALS spinal cord. To investigate the roles of microglia in ALS, we examined the appearance of ionized calcium-binding adaptor molecule 1-positive (Iba1-positive) microglia as correlated to the disease duration and immunohistochemical expression of neurogrowth factors in the ALS spinal cord. In this study, the number of Ibal-positive rod-like microglia significantly increased in the ALS spinal cord compared to controls. The number of ramified microglia was positively correlated with the number of normal-looking neurons and clinical duration of ALS patients; however, the number of rod-like microglia was not correlated with that of abnormal neurons, nor with the clinical duration of the disease. Some rod-like microglia were positive for anti-insulin-like growth factor-II (IGF II) and anti-leukemia inhibitory factor (LIF) immunostaining. Motor neurons in the ALS spinal cords also showed immunore-activity for IGF-II, LIF and the receptors of IGF-II and LIE Taken together, these findings suggest that at least some microglia might have a protective effect on motor neurons in the ALS spinal cord. Neuroprotective and/or neurotoxic effects of microglia on motor neurons should be further studied.
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PMID:Expression of insulin-like growth factor-II and leukemia inhibitory factor antibody immunostaining on the ionized calcium-binding adaptor molecule 1-positive microglias in the spinal cord of amyotrophic lateral sclerosis patients. 1764 40