J Oral Maxillofec 49:968-971.
Surg
1990
/den tifica tion of Prostaglandin E2 and Leukotriene B, in the Synovial Fluid of Painful, Dysfunctional Temporomandibular Joints JAMES H. QUINN, DDS,* AND NICOLAS G. BAZAN, MD, PtiDt It has been hypothesized that prostaglandin E2 (PGE,) and leukotriene B, (LTB,) should be present in the synovial fluid of inflamed, dysfunctional temporomandibular joints. An assay to identify PGE2 and LTB, and platelet-activating factor (PAF) was used, and a strong correlation between the levels of these lipid mediators of pain and inflammation and an index of clinical joint pathology was found.
The painful, dysfunctional temporomandibular (TMJ) joint is caused by stress-related, prolonged microtrauma caused by hyperactivity of the masticatory muscles (bruxism). This produces a chronic inllammatory condition, and mediators of inflammation and pain may play a role in this disorder as they do in other synovial joints. The pathophysiologic events leading to the painful, dysfunctional TMJ are not well understood. The identification of chemical mediators in the TMJ synovial fluid that may be involved in pain and inflammation could contribute information useful for the design of therapeutic strategies for their management. Collagen degeneration occurs within the TMJs of patients with chronic joint pain and is found in the synovial fluid.’ Plasma proteins involved in the inflammatory process have also been found in synovial fluid. These proteins include haptoglobin, ceruloplasmin, complement C3, and fibrinogen. Moreover, the immunoglobulins IgG and IgM have been shown to be present.’ In synovial fluid from patients with several inflammatory joint disorders, oxygenated metabolites Received from Louisiana State University Medical Center, New Orleans, LA. * Professor, Department of Oral and Maxillofacial Surgery. t Professor, Departments of Ophthalmology, Biochemistry and Molecular Biology, and Neurology. Address correspondence and reprint requests to Dr Quinn: LSU School of Dentistry, 1100 Florida Ave, Box 220, New Orleans, LA 70119. 0 1990 American geons
Association
0278-2391/90/4809-0010$3.00/0
of Oral and Maxillofacial
Sur-
of the arachidonic acid cascade have been found.‘-’ Among these are the prostaglandins D,, E,, FZa, 6-Keto, Ft,, thromboxane A, (TX,), prostacyclin, and leukotriene B,. The arachidonic acid cascade is triggered by the activation of phospholipase AZ, a membrane-bound enzyme that cleaves the arachidonoyl acyl chain of membrane phospholipids. Inflammation promotes the secretion of phospholipase A, into the extracellular space, and it has been found in the synovial fluid of arthritic patients.’ Figure 1 illustrates the production of prostaglandin E, (PGE2), leukotriene B, (LTB,), and another powerful mediator, thrombaxane. Prostaglandin E2 is a powerful vasodilator of capillaries, increases vascular permeability, and can cause bone resorption. to Leukotriene B4 triggers vascular permeability and is a powerful chemoattractant and activator of intlammatory cells. In this study, PGE,, LTB,, and plateletactivating factor (PAF) were assayed. Plateletactivating factor is accumulated during intlammation and in immune reactions, and its synthesis involves the release of arachidonic acid from the precursor by phospholipase A2.r1 To the best of our knowledge, no previous studies have been carried out to identify these mediators in TMJ synovial fluid in patients with chronic arthralgia related to internal disc derangement. Materials and Methods Nineteen samples of TMJ synovial fluid from 14 patients (13 female and 1 male) with chronic TMJ
969
QUINN AND BAZAN
PAIN MEDIATOR Trauma
CASCADE
1 IMicro-Macro)
I Collegenases-(Bradyiinin)
-Cathepsin
B+ D
(Phospholipase
Cell Membrane
I
A2)
/
(Phospholipid)
I
Arachidonic
Acid
FIGURE 1. Diagram of modified arachidonic acid cascade identifying the powerful metabolites of pain and infknmation, PGE, and LTB,, found in TMJ synovial fluid.
I
yConverted Cyclooxygenase
*\
1 HPETE
I Prostaglandins 62 & H2 I Prostaglandin (PGE2)
E2
/ Thrombaxane A2+B2
internal derangement and pain were assayed for PGE,, LTB,, and PAF. There were no control samples from normal temporomandibular joints because it is extremely difficult to obtain such samples. However, it is unlikely that mediators of pain and inflammation would be present in a normal joint. Samples were obtained during TMJ arthroscopic surgery involving patients with painful internal joint derangement. Saline (1.5 mL) was injected into the superior joint space and the condyle and disc were translated in order to mix the saline with the synovial fluid, which was then aspirated and collected. Synovial fluid samples were frozen at -70°C until assayed. Arthroscopic videotapes were recorded during the arthroscopic surgery, and the stage of acute TMJ synovitis present in each joint was graded (Table 1). Radioimmunoassay was used to identify PGE, and LTB,. ‘* The metabolite content of the synovial fluid samples was calculated by interpolating the valTable 1.
Lipoxygenase
Acute Synovitis Index
Grade 1 Dilation of superficial synovial blood vessels Grade 2 Superficial vascular dilation with minimal synovial membrane hyperemia Grade 3 Superficial vascular dilation with moderate synovial membrane hyperemia Grade 4 Advanced generalized synovial membrane hyperemia
I Leukotriene (LTA41
A4
I Leukotrlene (LTW)
84
ues from standard displacement curves; values were corrected for procedural losses, and were expressed as picogram per milliliter. All determinations were performed in duplicate. Assay Results of WE, and LTB, Concentrations in Each TMJ Sample With Acute Synovitis Index Beterminations
Table 2.
PGE, Sample 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17* 18t 19t
TMJ
LTB,
@g/mL) (p&W
R R L R R L R L L R L R R L R R R R L
* First arthroscopic
364 277 410 261 528 652 410 287 689 357 0 95 700 1367 680 347 1600 264 900 surgery. surgery.
t Second arthroscopic
400 254 463 160 586 600 188 750 667 371 144 231 0 867 578 217 1520 627 627
PAF
@rW.-) 0 0 0 0
Acute Synovitis Index 3 3 4 3 4 4 2 4 3 2 1 1 4 4 3 2 4 3 3
970
PGE, AND LTB, IN TMJ SYNOVIAL FLUID
1600 1400 M 1200 1000 E 2
800 600
0 .
FIGURE 2.
“1
2
3
4
Acute synovitis Index Graphs correlating the individual TMJ concentrations
A bioassay process was used to attempt to identify PAF.13 Washed rabbit platelets were suspended in a modified Tyrode’s buffer at pH 7.5. Platelets were stirred at 1,200 rpm at 37°C and the amount of light transmitted through the cell suspension was recorded using an aggregometer. The presence of PAF was determined by the change in transmittance that was measured. Results Eighteen of the 19 samples contained significant amounts of PGE, (160 to 1,520 pg/mL) and LTB, (95 to 1,600 pg/mL) (Table 2). Four samples in which PAF was assayed showed undetectable levels. The relationship of the concentration of eicosanoids to the acute synovitis inflammatory index is illustrated in Fig 2. This index represents increasing severity of joint pathology. Therefore, there is a close correlation between the content of lipid mediators and the clinical appearance of TMJ synovitis. Discussion Eicosanoids are derived from the oxygenation pathways of arachidonic acid after phospholipase A, has released fatty acids. Recently, phospholipase A,, the enzyme responsible for the accumulation of arachidonic acid, has been found in human synovial fluid.’ Moreover, eicosanoids are involved in pain and inflammation,14 as well as the regulation of pain sensitivity. l5 Two powerful mediators of pain and inflammation have been identified in significant concentrations in synovial fluid of inflamed TMJs for the first
0:
0 1
2
3
4
Acute synovitis Index
of (A) PGE, and (E) LTB, with their acute synovitis index.
time. This provides biochemical evidence that the same pain mediators present in other inflamed synovial joints are present in the inflamed TMJ synovial joint. These are thought to be involved in the attendant arthralgia. This could provide the basis for the use of specific antagonist chemicals to treat this painful TMJ disease. References 1. Kopp S, Wenneberg B, Clemensson E: Clinical, microscopical and biochemical investigation of synovial fluid from temporomandibular joints. Stand J Dent Res 91:33, 1983 2. Higgs GA, Vane JR, Haart FD, et al: Effect of antiinflammatory drugs on prostaglandins in rheumatoid arthritis, prostaglandin synthetase inhibitors, in Robinson HJ, Vane JR (eds): Prostaglandin Synthetase Inhibitors. New York, NY, Raven, 1974, pp 165-173 3. Trang LE, Granstrom E, Lovgren 0: Levels of prostaglandins F, and E, and thromboxane B, in joint fluid in rheumatoid arthritis. Stand J Rheumatol 6: 161, 1977 4. Sturge RA, Yates DB, Gordon D, et al: Prostaglandin duction in arthritis. Ann Rheum Dis 37:315, 1978
pro-
5. Davidson EM, Rae SA, Smith MJH: Leukotriene B4, a mediator of inflammation present in synovial fluid in rheumatoid arthritis. Arm Rheum Dis 42:677, 1983 6. Henderson B, Higgs GA: Synthesis of arachidonate oxidation products by synovial joint tissues during the development of chronic erosive arthritis. Arthritis Rheum 30: 1149, 1987 7. Brodie MJ, Hensby CN, Park A, et al: Is prostacylin the major pro-inflammatory prostanoid in joint fluid? Life Sci 27603, 1980 8. Egg D: Concentration of prostaglandins D,, E,, F,,, 6keto-F,, and thromboxane B, in synovial fluid from patients with inflammatory joint disorders in osteoarthritis. Zeitschr Rheumato143:89, 1984 9. Lai C-Y, Wada K: Phospholipase A, from human synovial fluid: Purification and structural homology to the placental enzyme. Biochem Biophys Res Commun 157:488,1988 10. Robinson DR, Tashjian AH, Levine L: Prostaglandin
stim-
QUINN AND BAZAN
mated bone resorption by rheumatoid synovia. J Clin Invest 56:1181, 1975 11. Braquet P, Touqui L, Shen TY, et al: Perspectives in platelet-activating factor research. Pharmacol Rev 39:97, 1987 12. Bazan NC, Bazan HEP, Birkle DL, et al: Synthesis of leukotrienes in the frog retina and retinal pigment epithelium. J Neurosci Res 18591, 1987 13. Bazan HEP, Reddy STK, Woodland JM. et al: The accumu-
971
lation of platelet-activating factor in the injured cornea may be interrelated with the synthesis of lipoxygenase products. Biochem Biophys Res Commun 149:915, 1987 14. Davies P, Bailey PJ, Goldenherg MM: The role of arachidonic acid oxygenation products in pain and inflammation. Ann Rev Immunol 2:335, 1984 15. Berge O-G: Regulation of pain sensitivity, influence of prostaglandins. Cephalalgia 4:21, 1986 (suppl)
Surg
1990
/den tifica tion of Prostaglandin E2 and Leukotriene B, in the Synovial Fluid of Painful, Dysfunctional Temporomandibular Joints JAMES H. QUINN, DDS,* AND NICOLAS G. BAZAN, MD, PtiDt It has been hypothesized that prostaglandin E2 (PGE,) and leukotriene B, (LTB,) should be present in the synovial fluid of inflamed, dysfunctional temporomandibular joints. An assay to identify PGE2 and LTB, and platelet-activating factor (PAF) was used, and a strong correlation between the levels of these lipid mediators of pain and inflammation and an index of clinical joint pathology was found.
The painful, dysfunctional temporomandibular (TMJ) joint is caused by stress-related, prolonged microtrauma caused by hyperactivity of the masticatory muscles (bruxism). This produces a chronic inllammatory condition, and mediators of inflammation and pain may play a role in this disorder as they do in other synovial joints. The pathophysiologic events leading to the painful, dysfunctional TMJ are not well understood. The identification of chemical mediators in the TMJ synovial fluid that may be involved in pain and inflammation could contribute information useful for the design of therapeutic strategies for their management. Collagen degeneration occurs within the TMJs of patients with chronic joint pain and is found in the synovial fluid.’ Plasma proteins involved in the inflammatory process have also been found in synovial fluid. These proteins include haptoglobin, ceruloplasmin, complement C3, and fibrinogen. Moreover, the immunoglobulins IgG and IgM have been shown to be present.’ In synovial fluid from patients with several inflammatory joint disorders, oxygenated metabolites Received from Louisiana State University Medical Center, New Orleans, LA. * Professor, Department of Oral and Maxillofacial Surgery. t Professor, Departments of Ophthalmology, Biochemistry and Molecular Biology, and Neurology. Address correspondence and reprint requests to Dr Quinn: LSU School of Dentistry, 1100 Florida Ave, Box 220, New Orleans, LA 70119. 0 1990 American geons
Association
0278-2391/90/4809-0010$3.00/0
of Oral and Maxillofacial
Sur-
of the arachidonic acid cascade have been found.‘-’ Among these are the prostaglandins D,, E,, FZa, 6-Keto, Ft,, thromboxane A, (TX,), prostacyclin, and leukotriene B,. The arachidonic acid cascade is triggered by the activation of phospholipase AZ, a membrane-bound enzyme that cleaves the arachidonoyl acyl chain of membrane phospholipids. Inflammation promotes the secretion of phospholipase A, into the extracellular space, and it has been found in the synovial fluid of arthritic patients.’ Figure 1 illustrates the production of prostaglandin E, (PGE2), leukotriene B, (LTB,), and another powerful mediator, thrombaxane. Prostaglandin E2 is a powerful vasodilator of capillaries, increases vascular permeability, and can cause bone resorption. to Leukotriene B4 triggers vascular permeability and is a powerful chemoattractant and activator of intlammatory cells. In this study, PGE,, LTB,, and plateletactivating factor (PAF) were assayed. Plateletactivating factor is accumulated during intlammation and in immune reactions, and its synthesis involves the release of arachidonic acid from the precursor by phospholipase A2.r1 To the best of our knowledge, no previous studies have been carried out to identify these mediators in TMJ synovial fluid in patients with chronic arthralgia related to internal disc derangement. Materials and Methods Nineteen samples of TMJ synovial fluid from 14 patients (13 female and 1 male) with chronic TMJ
969
QUINN AND BAZAN
PAIN MEDIATOR Trauma
CASCADE
1 IMicro-Macro)
I Collegenases-(Bradyiinin)
-Cathepsin
B+ D
(Phospholipase
Cell Membrane
I
A2)
/
(Phospholipid)
I
Arachidonic
Acid
FIGURE 1. Diagram of modified arachidonic acid cascade identifying the powerful metabolites of pain and infknmation, PGE, and LTB,, found in TMJ synovial fluid.
I
yConverted Cyclooxygenase
*\
1 HPETE
I Prostaglandins 62 & H2 I Prostaglandin (PGE2)
E2
/ Thrombaxane A2+B2
internal derangement and pain were assayed for PGE,, LTB,, and PAF. There were no control samples from normal temporomandibular joints because it is extremely difficult to obtain such samples. However, it is unlikely that mediators of pain and inflammation would be present in a normal joint. Samples were obtained during TMJ arthroscopic surgery involving patients with painful internal joint derangement. Saline (1.5 mL) was injected into the superior joint space and the condyle and disc were translated in order to mix the saline with the synovial fluid, which was then aspirated and collected. Synovial fluid samples were frozen at -70°C until assayed. Arthroscopic videotapes were recorded during the arthroscopic surgery, and the stage of acute TMJ synovitis present in each joint was graded (Table 1). Radioimmunoassay was used to identify PGE, and LTB,. ‘* The metabolite content of the synovial fluid samples was calculated by interpolating the valTable 1.
Lipoxygenase
Acute Synovitis Index
Grade 1 Dilation of superficial synovial blood vessels Grade 2 Superficial vascular dilation with minimal synovial membrane hyperemia Grade 3 Superficial vascular dilation with moderate synovial membrane hyperemia Grade 4 Advanced generalized synovial membrane hyperemia
I Leukotriene (LTA41
A4
I Leukotrlene (LTW)
84
ues from standard displacement curves; values were corrected for procedural losses, and were expressed as picogram per milliliter. All determinations were performed in duplicate. Assay Results of WE, and LTB, Concentrations in Each TMJ Sample With Acute Synovitis Index Beterminations
Table 2.
PGE, Sample 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17* 18t 19t
TMJ
LTB,
@g/mL) (p&W
R R L R R L R L L R L R R L R R R R L
* First arthroscopic
364 277 410 261 528 652 410 287 689 357 0 95 700 1367 680 347 1600 264 900 surgery. surgery.
t Second arthroscopic
400 254 463 160 586 600 188 750 667 371 144 231 0 867 578 217 1520 627 627
PAF
@rW.-) 0 0 0 0
Acute Synovitis Index 3 3 4 3 4 4 2 4 3 2 1 1 4 4 3 2 4 3 3
970
PGE, AND LTB, IN TMJ SYNOVIAL FLUID
1600 1400 M 1200 1000 E 2
800 600
0 .
FIGURE 2.
“1
2
3
4
Acute synovitis Index Graphs correlating the individual TMJ concentrations
A bioassay process was used to attempt to identify PAF.13 Washed rabbit platelets were suspended in a modified Tyrode’s buffer at pH 7.5. Platelets were stirred at 1,200 rpm at 37°C and the amount of light transmitted through the cell suspension was recorded using an aggregometer. The presence of PAF was determined by the change in transmittance that was measured. Results Eighteen of the 19 samples contained significant amounts of PGE, (160 to 1,520 pg/mL) and LTB, (95 to 1,600 pg/mL) (Table 2). Four samples in which PAF was assayed showed undetectable levels. The relationship of the concentration of eicosanoids to the acute synovitis inflammatory index is illustrated in Fig 2. This index represents increasing severity of joint pathology. Therefore, there is a close correlation between the content of lipid mediators and the clinical appearance of TMJ synovitis. Discussion Eicosanoids are derived from the oxygenation pathways of arachidonic acid after phospholipase A, has released fatty acids. Recently, phospholipase A,, the enzyme responsible for the accumulation of arachidonic acid, has been found in human synovial fluid.’ Moreover, eicosanoids are involved in pain and inflammation,14 as well as the regulation of pain sensitivity. l5 Two powerful mediators of pain and inflammation have been identified in significant concentrations in synovial fluid of inflamed TMJs for the first
0:
0 1
2
3
4
Acute synovitis Index
of (A) PGE, and (E) LTB, with their acute synovitis index.
time. This provides biochemical evidence that the same pain mediators present in other inflamed synovial joints are present in the inflamed TMJ synovial joint. These are thought to be involved in the attendant arthralgia. This could provide the basis for the use of specific antagonist chemicals to treat this painful TMJ disease. References 1. Kopp S, Wenneberg B, Clemensson E: Clinical, microscopical and biochemical investigation of synovial fluid from temporomandibular joints. Stand J Dent Res 91:33, 1983 2. Higgs GA, Vane JR, Haart FD, et al: Effect of antiinflammatory drugs on prostaglandins in rheumatoid arthritis, prostaglandin synthetase inhibitors, in Robinson HJ, Vane JR (eds): Prostaglandin Synthetase Inhibitors. New York, NY, Raven, 1974, pp 165-173 3. Trang LE, Granstrom E, Lovgren 0: Levels of prostaglandins F, and E, and thromboxane B, in joint fluid in rheumatoid arthritis. Stand J Rheumatol 6: 161, 1977 4. Sturge RA, Yates DB, Gordon D, et al: Prostaglandin duction in arthritis. Ann Rheum Dis 37:315, 1978
pro-
5. Davidson EM, Rae SA, Smith MJH: Leukotriene B4, a mediator of inflammation present in synovial fluid in rheumatoid arthritis. Arm Rheum Dis 42:677, 1983 6. Henderson B, Higgs GA: Synthesis of arachidonate oxidation products by synovial joint tissues during the development of chronic erosive arthritis. Arthritis Rheum 30: 1149, 1987 7. Brodie MJ, Hensby CN, Park A, et al: Is prostacylin the major pro-inflammatory prostanoid in joint fluid? Life Sci 27603, 1980 8. Egg D: Concentration of prostaglandins D,, E,, F,,, 6keto-F,, and thromboxane B, in synovial fluid from patients with inflammatory joint disorders in osteoarthritis. Zeitschr Rheumato143:89, 1984 9. Lai C-Y, Wada K: Phospholipase A, from human synovial fluid: Purification and structural homology to the placental enzyme. Biochem Biophys Res Commun 157:488,1988 10. Robinson DR, Tashjian AH, Levine L: Prostaglandin
stim-
QUINN AND BAZAN
mated bone resorption by rheumatoid synovia. J Clin Invest 56:1181, 1975 11. Braquet P, Touqui L, Shen TY, et al: Perspectives in platelet-activating factor research. Pharmacol Rev 39:97, 1987 12. Bazan NC, Bazan HEP, Birkle DL, et al: Synthesis of leukotrienes in the frog retina and retinal pigment epithelium. J Neurosci Res 18591, 1987 13. Bazan HEP, Reddy STK, Woodland JM. et al: The accumu-
971
lation of platelet-activating factor in the injured cornea may be interrelated with the synthesis of lipoxygenase products. Biochem Biophys Res Commun 149:915, 1987 14. Davies P, Bailey PJ, Goldenherg MM: The role of arachidonic acid oxygenation products in pain and inflammation. Ann Rev Immunol 2:335, 1984 15. Berge O-G: Regulation of pain sensitivity, influence of prostaglandins. Cephalalgia 4:21, 1986 (suppl)
