Charles W. Denko

Protective role of ceruloplasmin in inflammation

Experimental inflammation in copper Cu)-deficient rats is greater than that induced in controls eating normal diet. Cu-supplementation of the Cu-deficient diet results in a reduced swelling, down to normal levels. Injection of the naturally occurring acute phase reactant, ceruloplasmin (Cp) a Cu-bearing serum protein, also results in reduction of experimental inflammation. Since a rise in serum Cp occurs in normal pregnancy this protective anti-inflammatory action in normal pregnancy this protective anti-inflammatory action of Cp is proposed as an explanation for the widely-observed phenomenon of spontaneous control of rheumatoid arthritis in pregnancy.

Growth factors, insulin-like growth factor-1 and growth hormone, in synovial fluid and serum of patients with rheumatic disorders.

OBJECTIVE Synovial fluid (SF) plays an important role in joint function. We evaluated the growth factors, insulin-like growth factor-1 (IGF-1) and growth hormone (GH) in SF and serum from patients with osteoarthritis (OA), rheumatoid arthritis (RA), gout, pseudogout and diffuse idiopathic skeletal hyperostosis (DISH). DESIGN Standard radioimmunoassay techniques were used to measure concurrent levels of IGF-1 and GH. SF samples and serum samples were obtained concomitantly from 27 patients with OA, 22 patients with RA, nine men with gout, 14 patients with pseudogout and eight men with DISH. RESULTS In the case of IGF-1, a comparison of serum and SF levels shows that SF levels of IGF-1 are lower than serum levels in all groups. Men and women gave similar values. In contrast, in the case of GH, all groups, except males with RA, had higher GH values in SF when compared with serum values. Individual patients with other forms of arthritis demonstrated similar relationships. CONCLUSION The finding that IGF-1 is present in levels about one-half as great in SF as compared with serum suggests that IGF-1 may be produced in lesser amounts or is utilized by the patient in customary joint function. The finding that GH is present in SF at values twice as high, or more, of serum levels in inflammatory arthritides suggests that GH may play a role in the pathophysiology of arthritic disorders.

Sympathetic or reflex footpad swelling due to crystal-induced inflammation in the opposite foot

Sympathetic or reflex footpad swelling occurred in rats when several crystals known to be pathogenic in human joints or soft tissues were injected into the opposite footpad. Monosodium urate (MSU), calcium pyrophosphate dihydrate (CaPPD), hydroxyapatite, calcium oxalate (CaOx), and xanthine (X) suspension induced varying degrees of such reflex or sympathetic swelling. In the second cycle of crystal-induced swelling, the foot that had been the initial or primary site of inflammation reacted with greater reflex swelling, when compared to the first cycle. Similarly, reflex increases in temperature occurred when CaPPD was injected. These reflex increases in swelling and temperature may relate to signs and symptoms of patients with reflex neurovascular dystrophy or shoulder-hand syndrome.

Modification of adjuvant inflammation in rats deficient in essential fatty acids

Rats deficient in essential fatty acids (EFA) did not develop as much foot swelling on receiving injections of complete Freunds adjuvant as did normal controls. Both the acute inflammation and the chronic inflammation were affected. This reduction in the chronic phase of adjuvant inflammation was restored to normal levels by feeding a small supplement of corn oil as a dietary source of EFA. Since the EFA are biologic precursors of prostaglandins (PG), the lack of EFA is thought to influence adjuvant-induced inflammation by reducing available PG mediators of inflammation.Rats deficient in essential fatty acids (EFA) did not develop as much foot swelling on receiving injections of complete Freunds adjuvant as did normal controls. Both the acute inflammation and the chronic inflammation were affected. This reduction in the chronic phase of adjuvant inflammation was restored to normal levels by feeding a small supplement of corn oil as a dietary source of EFA. Since the EFA are biologic precursors of prostaglandins (PG), the lack of EFA is thought to influence adjuvant-induced inflammation by reducing available PG mediators of inflammation.

Effect of Prostaglandins in Urate Crystal Inflammation

By use of two novel techniques for detecting extremely small amounts of PGs, studies were conducted elucidating the mechanism of urate crystal-induced inflammation. Rats deficient in EFA and thus deficient in PGs received injections of monosodium urate crystals into the footpad. The EFA-deficient animals developed less swelling than did normal animals. However, when a 1-ng dose of PGE-1, PGE-2, PGA-2, or PGF-2-alpha was added along with the urate injection the swelling was enhanced to approximately normal levels. In the second technique the swelling induced by injection of two different urate crystals was compared. Urate crystals heated to 200 degrees C produced less swelling in normal rats than did similar urate crystals heated only to 50 degrees C. However when a 1-ng dose of PGE-1, PGE-2 or PGF-2-alpha was added to the heated urate crystals injection the swelling increased to approximately the swelling in normal controls receiving urate heated to 50 degrees C. Comments are presented suggesting that urate crystal inflammation may be a membrane disease.

Intra-erythrocyte deposition of growth hormone in rheumatic diseases

Abstract. Standard radioimmunoassay was employed to quantify matched basal intra-erythrocyte growth hormone (GH) and serum GH levels from patients with osteoarthritis, diffuse idiopathic skeletal hyperostosis (DISH), gout, and Sjögrens syndrome and in a group of normal volunteers (control group). Basal intra-erythrocyte GH concentration was significantly higher (P<0.05) than serum GH concentration in blood samples from patients with osteoarthritis and DISH but not from those with gout or Sjögrens syndrome. Regression analysis determined that basal serum GH levels did not correlate with age. While intra-erythrocyte GH levels exceeded serum GH levels in osteoarthritis and DISH, intra-erythrocyte GH was not a strong predictor of serum GH levels in osteoarthritis, DISH, or in the control group.

The serum growth hormone to somatostatin ratio is skewed upward in rheumatoid arthritis patients.

Basal serum growth hormone, insulin-like growth factor-1 (IGF-1) and somatostatin concentration were measured by standard radioimmunoassay in patients with a diagnosis of rheumatoid arthritis (RA) according to the criteria of the American College of Rheumatology as well as in a group of age-matched normal subjects. RA patients exhibited significantly elevated (age, 45-55 yrs, p less than 0.05; 55 yrs and older, p less than 0.01) serum growth hormone levels compared to age-matched individuals from the control group. IGF-1 was unchanged. Serum somatostatin levels were reduced in RA patients between 45 and 55 yrs but reached a significant reduction (p less than 0.0001) in RA patients, 55 years and older compared to age-matched individuals from the control group. RA patients treated with prednisone did not exhibit changes in either growth hormone or IGF-1 levels compared to RA patients treated principally with non-steroidal anti-inflammatory drugs and methotrexate. These results indicated that symptomatic RA is associated with elevated serum growth hormone without concomitant changes in IGF-1 compared to individuals from the control group. Reduced somatostatin levels in older RA patients resulted in a skewed upward growth hormone to somatostatin ratio. We conclude that the serum growth hormone to somatostatin ratio may be a useful surrogate marker of disease activity in symptomatic RA.

Anti-prostaglandin action of colchicine.

Colchicine, given locally, inhibits urate-crystal- and CaPPD-crystal-induced inflammation. Since this inflammation is known to be mediated in part by PGE1 these observations indicate colchicine acts as an anti-PG agent. Colchicine counteracts the phlogistic action of exogenous PGE1 in both urate- and CaPPD-crystal-induced inflammation. With use of large excesses of colchicine, its anti-inflammatory action appears limited to its anti-PGE1 activity. In turn, PGE1 counteracts the antiphlogistic action of colchicine. Colchicine is less effective in reducing swelling due to CaPPD-crystals than that due to urate-crystals, a finding similar to the clinical observations that colchicine is more effective therapy for gout than for pseudogout. Some relationships are reviewed to suggest that CaPPD-crystal inflammation is a more severe membrane disorder than is urate-crystal inflammation.

A new mechanical method for measuring rat paw edema.

A new method is presented for measuring swelling or rat paw edema in inflammation induced by carrageenin injection. This technique is compared to other widely used ones. A spring-loaded dial indicator produces results that are accurate, precise and reproducible. It is recommended for investigators seeking the advantages of a noninvasive, low cost, rapid method quantifying the swelling of inflammation.

Modification of cholesterool crystal-induced inflammation

Cholesterol crystals induced inflammation in normal rats upon being injected into the footpad. Cholesterol caused less swelling than did an equal amount (3 mg) of monosodium urate crystals. In rats made deficient in essential fatty acids on the basis of clinical criteria (thereby presumably being deficient in prostaglandins) cholesterol crystals did not produce normal levels of swelling. Injections of prostaglandin E1, prostacyclin and thromboxane (B2) did not result in perturbations in cholesterol-induced swelling. Colchicine and indomethacin, given systemically, were very effective in reducing cholesterol crystal-induced foot swelling. Prostaglandin E2 also demonstrated an anti-inflammatory effect.