Nephro- and Cardiotoxic Effects of Etoricoxib: Insights into Arachidonic Acid Metabolism and Beta-Adrenergic Receptor Expression in Experimental Mice

Abstract

Background: Etoricoxib is a widely used anti-inflammatory drug, but its safety profile concerning cardiovascular and renal health remains inadequately explored. This study aimed to assess the nephro- and cardiotoxic effects of etoricoxib in a murine model, with a focus on its impact on arachidonic acid-metabolizing enzymes and beta-adrenergic receptors associated with drug-induced toxicity. Methods: Thirty-five BALB/C mice were randomly assigned to five groups: control, low-dose etoricoxib, high-dose etoricoxib, low-dose celecoxib, and high-dose celecoxib (a well-known nephro- and cardiotoxic NSAID). The treatments were administered for 28 days, after which hearts and kidneys were excised for physical and histopathological analysis, and the expression of arachidonic acid-metabolizing enzymes (cytochrome P450s, lipoxygenases, cyclooxygenases) and beta-1 adrenergic receptor (adrb1) and angiotensin-converting enzyme (ace2) genes were quantified using quantitative reverse transcription PCR (qRT-PCR). Results: Etoricoxib administration resulted in dose-dependent nephro- and cardiotoxic effects. Renal histology revealed glomerular atrophy or hypertrophy and significant damage to the proximal and distal convoluted tubules, including epithelial flattening, cytoplasmic vacuolation, and luminal widening. Cardiac analysis showed disorganized muscle fibers and hyaline degeneration. These changes were associated with altered gene expression: the downregulation of cox2, cyp1a1, and cyp2c29 in the kidneys and the upregulation of cyp4a12, cox2, and adrb1, along with the downregulation of cyp2c29 and ace2 in the heart. Conclusions: Etoricoxib induces nephro- and cardiotoxicity, marked by alterations in arachidonic acid metabolism and beta-adrenergic signaling pathways. The drug affects the expression of arachidonic acid-metabolizing enzymes and adrb1 in the heart while downregulating cox2 and other related enzymes in the kidneys. These findings underscore the need for caution when prescribing etoricoxib, particularly in patients with pre-existing renal or cardiac conditions.

Keywords: arachidonic acid; cardiotoxicity; cytochrome P450s; etoricoxib; nephrotoxicity.

Figure 1

The effect of different doses of celecoxib and etoricoxib on the percentage change in body weight among groups. Data are presented as mean ± standard error of the mean (SEM). The effect of etoricoxib and celecoxib on the heart and kidney relative weight.

Figure 2

Representative photomicrographs of the H- & E-stained sections of the renal cortex from different groups after the administration of etoricoxib and celecoxib (H and E X 400). (A,B) represent the control group, with a normal structure containing renal corpuscles (RC) and proximal (PCT) and distal (DCT) convoluted tubules. The renal corpuscles consist of Bowman’s capsule (BC), which is lined by simple squamous and encloses the glomerulus (G) with normal capsular space (CS). The proximal convoluted tubules (PCT) are lined by tall cuboidal cells with acidophilic cytoplasm and a pale vesicular nucleus, while the distal convoluted tubules (DCT) are lined by short cuboidal cells with deeply stained nuclei. (C,D) represent the low-dose celecoxib group with some renal corpuscles (RC) showing atrophied glomeruli (G) and wide capsular space (CS). Some proximal (PCT) and distal convoluted (DCT) tubules have cytoplasmic vacuolation with dilated lumina. Notice the presence of some areas of interstitial hemorrhages (*). (E,F) represent the high-dose celecoxib group with many renal corpuscles (RC) having hypertrophied glomeruli (G) with decreased capsular space (CS). More proximal (PCT) and distal convoluted (DCT) tubules showed cytoplasmic vacuolation, a loss of brush borders, and wider lumina. Notice the presence of wide interstitial spaces (arrowhead) and areas of interstitial hemorrhages (*). (G,H) represent the low-dose etoricoxib group, showing some renal corpuscles (RC) having a distorted appearance with shrunken glomeruli (G) and wide capsular space (CS). In addition, some proximal (PCT) and distal convoluted (DCT) tubules have dilated lumina and a loss of brush borders. Notice the presence of some areas of wide spaces (arrowhead) and interstitial hemorrhages (*). (I,J) represent the high-dose etoricoxib group with some renal corpuscles (RC) having hypertrophied glomeruli (G) with decreased capsular space (CS). The proximal (PCT) and distal convoluted (DCT) tubules showed cytoplasmic vacuolation, a loss of brush borders, and wider lumina. Notice the presence of wide interstitial spaces (arrowhead), areas of interstitial hemorrhages (*), and inflammatory cellular infiltration (ICI).

Figure 2

Representative photomicrographs of the H- & E-stained sections of the renal cortex from different groups after the administration of etoricoxib and celecoxib (H and E X 400). (A,B) represent the control group, with a normal structure containing renal corpuscles (RC) and proximal (PCT) and distal (DCT) convoluted tubules. The renal corpuscles consist of Bowman’s capsule (BC), which is lined by simple squamous and encloses the glomerulus (G) with normal capsular space (CS). The proximal convoluted tubules (PCT) are lined by tall cuboidal cells with acidophilic cytoplasm and a pale vesicular nucleus, while the distal convoluted tubules (DCT) are lined by short cuboidal cells with deeply stained nuclei. (C,D) represent the low-dose celecoxib group with some renal corpuscles (RC) showing atrophied glomeruli (G) and wide capsular space (CS). Some proximal (PCT) and distal convoluted (DCT) tubules have cytoplasmic vacuolation with dilated lumina. Notice the presence of some areas of interstitial hemorrhages (*). (E,F) represent the high-dose celecoxib group with many renal corpuscles (RC) having hypertrophied glomeruli (G) with decreased capsular space (CS). More proximal (PCT) and distal convoluted (DCT) tubules showed cytoplasmic vacuolation, a loss of brush borders, and wider lumina. Notice the presence of wide interstitial spaces (arrowhead) and areas of interstitial hemorrhages (*). (G,H) represent the low-dose etoricoxib group, showing some renal corpuscles (RC) having a distorted appearance with shrunken glomeruli (G) and wide capsular space (CS). In addition, some proximal (PCT) and distal convoluted (DCT) tubules have dilated lumina and a loss of brush borders. Notice the presence of some areas of wide spaces (arrowhead) and interstitial hemorrhages (*). (I,J) represent the high-dose etoricoxib group with some renal corpuscles (RC) having hypertrophied glomeruli (G) with decreased capsular space (CS). The proximal (PCT) and distal convoluted (DCT) tubules showed cytoplasmic vacuolation, a loss of brush borders, and wider lumina. Notice the presence of wide interstitial spaces (arrowhead), areas of interstitial hemorrhages (*), and inflammatory cellular infiltration (ICI).

Figure 3

Representative photomicrographs of the ventricular wall of the hearts from different groups after the administration of etoricoxib and celecoxib (H and E X 400). (A,B) represent the longitudinal and transverse sections from the control group, with normal structure in the form of branched and anastomosing cardiac muscle fibers (C) which run in different directions with acidophilic cytoplasm and a poorly developed cross striation. Notice the presence of narrow interstitial spaces between the fibers that contain some nuclei of fibroblasts (🢧) and blood vessels (bv). The inset of high magnification showed elongated vesicular single nuclei (N) in cardiac muscle fibers. (C,D) represent the longitudinal and transverse sections from the low-dose celecoxib group with wavy and disarranged cardiac muscle fibers (C). Some fibers showed hyaline degeneration (*). Notice the presence of congested vessels (bv) and wide interstitial spaces (thick arrow). (E,F) represent the longitudinal and transverse sections from the high-dose celecoxib group with many cardiac muscle fibers (C) demonstrating disorganization and fragmentation with wide interstitial spaces (thick arrow) and congested blood vessels (bv). Notice that some cardiac muscle fibers showed pyknotic nuclei (thin arrow), while others showed hyaline degeneration (*). (G,H) represent the longitudinal and transverse sections from low dose etoricoxib group with some disorganization and wider interstitial spaces (thick arrow) between cardiac muscle fibers (C), with some fibers showing hyaline degeneration (*). (I,J) represent the longitudinal and transverse sections from the high-dose etoricoxib group with more disarrangement of cardiac muscle fibers (C) and wide interstitial spaces (thick arrow). Some of the fibers had lost their nuclei, while others showed pale acidophilic cytoplasm with pyknotic nuclei (thin arrow). Furthermore, some fibers showed more hyaline degeneration (*).

Figure 4

The mRNA expression of arachidonic acid-metabolizing cyp450 genes in the mouse kidneys after the administration of celecoxib and etoricoxib. The tested arachidonic acid-metabolizing cyp450 genes are cyp4a12 (A), cyp1a1 (B), cyp2c29 (C), and cyp2j5 (D). “C” is the abbreviation of celecoxib, and “E” is the abbreviation of etoricoxib. “*” indicates statistical significance (p < 0.05, ANOVA) in comparison to the control group.

Figure 5

The mRNA expression of arachidonic acid-metabolizing cyp450 genes in the mouse hearts after the administration of celecoxib and etoricoxib. The tested arachidonic acid-metabolizing cyp450 genes are cyp4a12 (A), cyp1a1 (B), cyp2c29 (C), and cyp2j5 (D). “C” is the abbreviation of celecoxib, and “E” is the abbreviation of etoricoxib. “*” indicates statistical significance (p < 0.05, ANOVA) in comparison to the control group, while “#” indicates statistical significance (p < 0.05, ANOVA) in comparison with the low dose of the same tested drug.

Figure 6

The mRNA expression of ephx2 gene in the mouse kidneys (A) and hearts (B) after administration of celecoxib and Etoricoxib. “C” is the abbreviation of celecoxib and “E” is the abbreviation of Etoricoxib. “*” indicates the statistical significance (p < 0.05, ANOVA) in comparison to the control group.

Figure 7

The mRNA expression of alox12 (A) and cox2 (B) genes in the mouse kidneys after administration of celecoxib and etoricoxib. “C” is the abbreviation of celecoxib, and “E” is the abbreviation of etoricoxib. “*” indicates statistical significance (p < 0.05, ANOVA) in comparison to the control group.

Figure 8

The mRNA expression of the alox12 (A) and cox2 (B) genes in the mouse hearts after the administration of celecoxib and etoricoxib. “C” is the abbreviation of celecoxib, and “E” is the abbreviation of etoricoxib. “*” indicates statistical significance (p < 0.05, ANOVA) in comparison to the control group, while “#” indicates statistical significance (p < 0.05, ANOVA) in comparison with the low dose of the same tested drug.

Figure 9

The mRNA expression of the adrb1 (A) and ace2 (B) genes in the mouse kidneys after the administration of celecoxib and etoricoxib. “C” is the abbreviation of celecoxib, and “E” is the abbreviation of etoricoxib.

Figure 10

The mRNA expression of the adrb1 (A) and ace2 (B) genes in the mouse hearts after the administration of celecoxib and etoricoxib. “C” is the abbreviation of celecoxib, and “E” is the abbreviation of etoricoxib. “*” indicates statistical significance (p < 0.05, ANOVA) in comparison to the control group, while “#” indicates statistical significance (p < 0.05, ANOVA) in comparison with the low dose of the same tested drug.