Mitigating High-Fat Diet-Induced Testicular Oxidative Stress and Fibrosis with Bromelain

Year 2026, Volume: 12 Issue: 1, 1 - 12, 04.01.2026

Burcu Gültekin , Raviye Özen Koca , Halime Tuba Canbaz , Hasan Basri Savaş , Mustafa Berk Başaran , Z Işık Solak Görmüş

https://doi.org/10.18621/eurj.1792973

https://izlik.org/JA76MB88HT

Abstract

Objectives: Obesity induced by a high-fat diet (HFD) is closely associated with impaired male fertility, primarily through oxidative stress, inflammation, and testicular dysfunction. Natural compounds with antioxidant and anti-inflammatory properties have gained increasing attention for their potential therapeutic effects. Bromelain, a proteolytic enzyme complex derived from Ananas comosus, exhibits antioxidant, anti-inflammatory, and antifibrotic activities, suggesting potential protective effects against obesity-related reproductive impairments.

Methods: Male Wistar rats were randomly assigned to four groups (n=9 per group). Animals were fed an HFD for 12 weeks to induce obesity, followed by one month of bromelain supplementation. Testicular tissues were histologically assessed using hematoxylin & eosin (H&E) and Masson’s trichrome staining. Serum and testicular samples were analyzed for antioxidant and oxidative stress markers, including paraoxonase-1 (PON1), arylesterase (ARE), total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI).

Results: The HFD group showed significant testicular alterations, including thickening of the tunica albuginea, perivascular collagen accumulation, germ cell loss, and disrupted seminiferous tubule architecture (P<0.0001). Biochemically, TAS (P<0.0001) and PON1 (P=0.0041) levels were significantly decreased, whereas TOS (P<0.0001) and OSI (P<0.0001) levels were elevated. Bromelain supplementation mitigated histopathological changes, reducing collagen deposition and tunica albuginea thickness. Moreover, Bromelain significantly restored TAS and PON1 levels while decreasing TOS and OSI. No significant differences were observed in ARE (P=0.0002) activity between the groups.

Conclusions: Bromelain supplementation attenuated HFD-induced oxidative stress and fibrotic alterations in testicular tissue, improving both histological and biochemical parameters. These findings suggest that Br may be a potentially beneficial natural supplement for alleviating obesity-induced impairments in male reproductive functions and associated metabolic dysfunctions.

Keywords

Bromelain , Fibrosis , Oxidative Stress , Testis , High-Fat Diet

Ethical Statement

This study was approved by the Necmettin Erbakan University KONUDAM Experimental Medicine Application and Research Center Animal Experiments Local Ethics Committee (Decision No: 2024-117; date: 28.11.2024). All experimental procedures involving animals were conducted in accordance with the ethical standards of the Guide for the Care and Use of Laboratory Animals published by the U.S. National Institutes of Health. All efforts were made to minimize animal suffering and to reduce the number of animals used.

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