Experimental arthritis inhibits the insulin-like growth factor-I axis and induces muscle wasting through cyclooxygenase-2 activation

2007 ◽  
Vol 292 (6) ◽  
pp. E1656-E1665 ◽  
Author(s):  
Miriam Granado ◽  
Ana I Martín ◽  
Mª Ángeles Villanúa ◽  
Asunción López-Calderón

Chronic arthritis induces cachexia associated with an inhibition of the growth hormone (GH)-insulin-like growth factor-I (IGF-I) system and an activation of the E3 ubiquitin-ligating enzymes muscle atrophy F-box (MAFbx) and muscle Ring finger 1 (MuRF1) in the skeletal muscle. The aim of this work was to study the role of cyclooxygenase (COX)-2 in chronic arthritis-induced cachexia. Arthritis was induced in rats by Freund's adjuvant injection, and the effects of two COX inhibitors (indomethacin, a nonspecific inhibitor, and meloxicam, a selective COX-2 inhibitor on pituitary GH and on liver and serum IGF-I levels) were tested. Arthritis decreased body weight gain and GH and liver IGF-I gene expression. In the arthritic rats, both inhibitors, indomethacin and meloxicam, prevented the inhibitory effect of arthritis on body weight gain. Indomethacin and meloxicam administration to arthritic rats increased pituitary GH and liver IGF-I mRNA as well as serum levels of IGF-I. These data suggest that induction of COX-2 during chronic inflammation is involved in the inhibition of the GH-IGF-I axis and in the body weight loss. In the gastrocnemius muscle, arthritis increased the gene expression of tumor necrosis factor (TNF)-α, the E3 ubiquitin-ligating enzymes MAFbx and MuRF1, as well as of IGF-I and IGF-binding protein-5 (IGFBP-5). Inhibition of COX-2 by meloxicam administration increased gastrocnemius weight and decreased MAFbx, MuRF1, TNF-α, and IGFBP-5 gene expression. In summary, our data indicate that chronic arthritis-induced cachexia and muscle wasting are mediated by the COX-2 pathway resulting in a decreased GH-IGF-I secretion and increased expression of MAFbx and MuRF1 mRNA.

2010 ◽  
Vol 299 (2) ◽  
pp. R541-R551 ◽  
Author(s):  
María López-Menduiña ◽  
Ana Isabel Martín ◽  
Estíbaliz Castillero ◽  
María Angeles Villanúa ◽  
Asunción López-Calderón

Adjuvant arthritis is an animal model of rheumatoid arthritis that decreases liver and circulating IGF-I as well as skeletal muscle mass. The aim of this work was to elucidate whether IGF-I administration was able to prevent the effect of arthritis on body weight and on two skeletal muscles, gastrocnemius and soleus. On day 4 after adjuvant injection, control and arthritic rats were treated with IGF-I (100 μg/kg sc) two times a day, until day 15 when all rats were killed. Arthritis decreased body weight gain and gastrocnemius weight. In arthritic rats, IGF-I treatment increased body weight gain and gastrocnemius weight, without modifying food intake or the external signs of arthritis. Arthritis increased atrogin-1 and muscle ring finger 1 (MuRF1) gene expression in the gastrocnemius and to a lesser extent in the soleus muscle. IGF-I attenuated the arthritis-induced increase in atrogin-1 and MuRF1 expression in the gastrocnemius, whereas it did not modify the expression of these genes in the soleus muscle. Arthritis also increased IGF-binding protein (IGBP)-3 and IGFBP-5 gene expression in gastrocnemius and soleus, whereas IGF-I administration decreased IGFBP-3, but not IGFBP-5, gene expression in both muscles. In both groups of arthritic rats and in control rats treated with IGF-I, proliferating cell nuclear antigen and myogenic differentiation proteins were increased in the gastrocnemius. These data suggest that the inhibitory effect of chronic arthritis on skeletal muscle is higher in fast glycolytic than in slow oxidative muscle and that IGF-I administration attenuates this effect and decreases atrogin-1 and IGFBP-3 gene expression.


1989 ◽  
Vol 122 (1) ◽  
pp. 79-86 ◽  
Author(s):  
D. J. Flint ◽  
M. J. Gardner

ABSTRACT Treatment of rats for 24 h on day 2, 10 or 20 of age with a specific antiserum to rGH (anti-(rGH)), GH, bromocriptine (CB-154) or prolactin failed to influence body weight gain or serum concentrations of insulin-like growth factor-I (IGF-I). On day 28 of age, however, anti-(rGH) completely inhibited body weight gain and markedly reduced circulating IGF-I concentrations, effects which were completely prevented by exogenous ovine GH (oGH). When administered to control rats on day 28 oGH caused supranormal weight gain and serum IGF-I concentrations. These results suggested that GH does not play a significant role in growth or regulation of serum IGF-I until after day 20 of age. By contrast, when anti-(rGH) was given for 4 consecutive days beginning on day 2 of life, body weight gain was reduced within 48 h and remained so until at least 28 days of age. Tail length was also significantly reduced. The effect was due to inhibition of GH effects since serum GH concentrations were low and exogenous GH prevented the effect. Inhibition of growth during the first 14 days of life occurred in the absence of any effect on serum IGF-I although by 21 days of age serum IGF-I was considerably lower than in control rats. The prolonged reduction in growth after treatment has stopped appeared to be due to a cytotoxic effect on the pituitary gland since pituitary weight and GH but not prolactin content were significantly decreased. The data are consistent with the hypothesis that in the neonate GH may be processed in serum so that a proportion of it is not recognized by an antiserum to pituitary GH. It would appear that inhibition of GH secretion reduces growth rate by at least 30–40% up to 14 days of age, 50% by 21 days of age and completely by 28 days. Effects of GH on growth could not be fully explained by regulation of serum IGF-I concentrations. Journal of Endocrinology (1989) 122, 79–86


1991 ◽  
Vol 130 (2) ◽  
pp. 305-312 ◽  
Author(s):  
M. J. VandeHaar ◽  
B. M. Moats-Staats ◽  
M. L. Davenport ◽  
J. L. Walker ◽  
J.-M. Ketelslegers ◽  
...  

ABSTRACT The serum concentration of insulin-like growth factor-I (IGF-I) is reduced in growing rats fed a low-protein diet, and this decrease is age-dependent, being more pronounced in younger animals. To determine whether this decrease in serum IGF-I is related to a decrease in IGF-I mRNA, growing female rats were given free access to either a 15% protein-sufficient or a 5% protein-deficient diet for 1 week. Protein restriction in 4-week-old rats decreased body weight gain by 44% (P < 0·001) compared with 4-week controls), serum IGF-I concentration by 67% (P < 0·001) and liver IGF-I mRNA abundance by 51% (P < 0·001). During week 6, protein restriction for 1 week resulted in a 20% increase in food intake with no change in weight gain, a 38% reduction in serum IGF-I (P < 0·001 compared with 6-week controls) and a 39% decrease in liver IGF-I mRNA (P < 0·001). The serum IGF-I concentration was highly correlated (r = 0·80; P < 0·001) with the hepatic IGF-I mRNA concentration. Skeletal muscle IGF-I mRNA abundance was also decreased significantly by protein restriction (37% at week 4, P<0·001, and 24% at week 6, P < 0·01) and was closely correlated (r = 0·71; P < 0·001) with body weight gain. Liver GH-binding protein and GH receptor mRNA abundance were reduced by 1 week of protein deprivation at week 6 but not at week 4. We conclude that the reduced serum IGF-I of young rats fed a low-protein diet is due, in part, to reduced liver IGF-I mRNA, and that these changes are not dependent on GH binding. Decreased skeletal muscle IGF-I mRNA during protein restriction is consistent with an autocrine/paracrine action of IGF-I in muscle. Journal of Endocrinology (1991) 130, 305–312


Endocrine ◽  
1997 ◽  
Vol 6 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Nadine M. Gruaz ◽  
Violaine d'Allèves ◽  
Yves Charnay ◽  
Anna Skotther ◽  
Sven Ekvärn ◽  
...  

1994 ◽  
Vol 140 (1) ◽  
pp. 23-32 ◽  
Author(s):  
A A Martin ◽  
C M Gillespie ◽  
L Moore ◽  
F J Ballard ◽  
L C Read

Abstract The effect of insulin-like growth factor-I (IGF-I) administration on body weight gain and the rate of recovery of renal function was investigated in rats following an acute episode of renal ischaemia. Since the des(1–3)IGF-I and LR3IGF-I variant forms of IGF-I have been shown to be more potent than IGF-I, their effects were also examined. Acute renal failure was produced in male Sprague–Dawley rats by clamping both renal arteries for 45 min. Treatment was commenced at the time of renal artery occlusion with vehicle (0·1 mol acetic acid/l; control group), IGF-I (2·0 mg/kg per day), des(1–3)IGF-I (2·0 mg/kg per day) or LR3IGF-I (1·5 mg/kg per day) by s.c. osmotic pump, and continued for 7 days, with rats being held in metabolism cages. Glomerular filtration rate (GFR) was estimated by the use of 51Cr-EDTA continuously infused i.p. via osmotic pump. Following the episode of renal ischaemia, body weight gain and nitrogen retention were significantly improved in all three peptide-treated groups, and serum urea concentrations were reduced in the groups treated with IGF-I and des(1–3)IGF-I. However, there was no evidence of the variants having any increased potency over the growth effects of IGF-I itself. GFR was significantly reduced, urine output was increased and urinary concentrating ability was reduced in all groups compared with normal rats, with no significant effect of the IGF peptides being apparent. A closer examination of the acute effects of LR3IGF-I on renal function was undertaken by measuring GFR for 3 days before and 3 days after renal ischaemia in two groups of rats, treated for the latter 3 days with either vehicle (controls) or LR3IGF-I (1·5 mg/kg per day). LR3IGF-I treatment following renal ischaemia resulted in a significantly greater fall in GFR than in controls, urinary osmolality was also significantly reduced, and fractional excretion of sodium was increased. In addition, there was histological evidence of a greater degree of tubular epithelial calcification in the kidneys of the rats treated with LR3IGF-I. This study showed that administration of IGF peptides at doses sufficient to cause significant improvement in anabolic status did not improve renal function in rats following an acute episode of renal ischaemia. Indeed the LR3IGF-I variant of IGF-I had a deleterious effect on renal function in the early stage of the recovery period. Journal of Endocrinology (1994) 140, 23–32


2007 ◽  
Vol 97 (2) ◽  
pp. 389-398 ◽  
Author(s):  
Patricia Pérez-Matute ◽  
Nerea Pérez-Echarri ◽  
J. Alfredo Martínez ◽  
Amelia Marti ◽  
María J. Moreno-Aliaga

n-3 PUFA have shown potential anti-obesity and insulin-sensitising properties. However, the mechanisms involved are not clearly established. The aim of the present study was to assess the effects of EPA administration, one of the n-3 PUFA, on body-weight gain and adiposity in rats fed on a standard or a high-fat (cafeteria) diet. The actions on white adipose tissue lipolysis, apoptosis and on several genes related to obesity and insulin resistance were also studied. Control and cafeteria-induced overweight male Wistar rats were assigned into two subgroups, one of them daily received EPA ethyl ester (1 g/kg) for 5 weeks by oral administration. The high-fat diet induced a very significant increase in both body weight and fat mass. Rats fed with the cafeteria diet and orally treated with EPA showed a marginally lower body-weight gain (P = 0·09), a decrease in food intake (P < 0·01) and an increase in leptin production (P < 0·05). EPA administration reduced retroperitoneal adipose tissue weight (P < 0·05) which could be secondary to the inhibition of the adipogenic transcription factor PPARγ gene expression (P < 0·001), and also to the increase in apoptosis (P < 0·05) found in rats fed with a control diet. TNFα gene expression was significantly increased (P < 0·05) by the cafeteria diet, while EPA treatment was able to prevent (P < 0·01) the rise in this inflammatory cytokine. Adiposity-corrected adiponectin plasma levels were increased by EPA. These actions on both TNFα and adiponectin could explain the beneficial effects of EPA on insulin resistance induced by the cafeteria diet.


2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Weidong Xu ◽  
Jiayao Li ◽  
Weipeng Qi ◽  
Ye Peng

Apigenin-8-C-glucoside (vitexin), a natural phytochemical contained in hawthorn, has been reported to have versatile beneficial bioactivities, such as antioxidation, anticancer property, and adipogenesis inhibition. The present research aimed to determine the influence of vitexin on insulin resistance elicited by HFD in mice and HepG2 cells. Vitexin markedly alleviated body weight gain and improved glucose and insulin intolerance induced by HFD. Vitexin partially normalized blood glucose, cholesterol, TNF-α, and hepatic lipid content. Moreover, vitexin recovered the reduced glucose uptake induced by glucosamine. The present results indicate that vitexin prevents HFD-induced insulin resistance.


2000 ◽  
Vol 165 (3) ◽  
pp. 537-544 ◽  
Author(s):  
I Ibanez De Caceres ◽  
MA Villanua ◽  
L Soto ◽  
AI Martin ◽  
A Lopez-Calderon

Adjuvant-induced arthritis in rats is associated with growth failure, hypermetabolism and accelerated protein breakdown. We have previously reported that adjuvant-induced arthritis in rats results in a decrease in body weight gain, pituitary GH mRNA, circulating GH and IGF-I together with an increase in serum IGF-binding proteins (IGFBPs). The aim of this study was to analyze the role of GH in the decrease in body weight and in the alterations in the IGF-I system observed in chronic inflammation. Male Wistar rats were injected with complete Freund's adjuvant and 16 days later arthritic rats were injected daily with recombinant human GH (rhGH) (3 IU/kg s.c.) for 8 days; control rats received 250 microl saline. Arthritis significantly decreased body weight gain and serum IGF-I. These decreases were not due to the reduced food intake, since in pair-fed rats they were not observed. Furthermore, administration of rhGH to arthritic rats increased body weight gain without modifying food intake. To further investigate the effect of GH administration, 14 days after adjuvant injection both control and arthritic rats were treated with 0, 1.5, 3 or 6 IU/kg of rhGH. GH treatment at the dose of 3 and 6 IU/kg significantly increased body weight gain in arthritic rats. GH administration, at the higher dose of 6 IU/kg, increased hepatic and serum concentrations of IGF-I in both control and arthritic rats. In control rats, rhGH at the three doses assayed increased circulating IGFBP-3. GH treatment in arthritic rats decreased IGFBP-1 and -2, and did not modify IGFBP-4. GH treatment at the dose of 3 IU/kg also decreased circulating IGFBP-3 in arthritic rats. These data suggest that GH treatment can ameliorate the catabolism observed in adjuvant-induced arthritis, an effect mediated, at least in part, by modifications in the circulating IGFBPs.


2002 ◽  
Vol 47 (8) ◽  
pp. 742-749 ◽  
Author(s):  
Trino Baptista ◽  
Serge Beaulieu

Objective: To critically review published literature on the causal association between leptin, cytokines, and excessive body weight gain (BWG) induced by antipsychotic drugs (APs). Methods: We completed a Medline search using the words leptin, cytokines, antipsychotic drugs, neuroleptics, psychotropic drugs, weight gain, and obesity. We also included our empirical research on this topic in the discussion. We examined the relation between leptin, cytokines (mainly tumour necrosis factor alpha [TNF-α] and its soluble receptors), and AP-induced BWG, using the biological sciences' current theories of causality. Results: In the general field of weight regulation, there is scarce experimental evidence that leptin or TNF-α by themselves can induce obesity. Serum levels of leptin and TNF-α rather increase simultaneously as BWG occurs. This has also been reported during AP-induced BWG, with the equivocal exception of a study with clozapine. Some researchers have suggested that the absence of the expected correlation between leptin and body mass index (BMI) or serum insulin levels, and the lack of sex-related differences in leptin levels in AP-treated patients, may point to a causal relation. This contention requires more experimental support. In addition, future clinical studies must carefully control for sex and BMI. Conclusions: No conclusive evidence has been provided that leptin or TNF-α may induce obesity either in drug-free subjects or in AP-treated patients. In most cases, the elevated serum levels of these hormones appear to be a consequence rather than a cause of obesity. That does not mean that such an elevation is innocuous, since it may impair blood pressure and also carbohydrate and lipid metabolism regulation. Hence, all efforts should be made to prevent or attenuate BWG during treatment with APs.


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