Potential Use of Tannin Extracts as Additives in Semen Destined for Cryopreservation: A Review

Abstract

Cryopreservation and storage of semen for artificial insemination (AI) result in excessive accumulation of reactive oxygen species (ROS). This leads to a shortened life span and reduced motility of spermatozoa post-thawing, with consequent impairment of their function. However, certain levels of ROS are essential to facilitate the capacitation of spermatozoa required for successful fertilisation. Tannins, as well-known antioxidant compounds, may act as ROS binders/acceptors/scavengers to inhibit the damaging effects of ROS. This review comprises an analysis of the semen cryopreservation protocol and health functions of tannins, as well as the effects of ROS on fresh and cryopreserved semen’s longevity and fertilisation. Additionally, we surveyed available evidence of the effects of tannin extract feed supplementation on male fertility. We furthermore interrogated existing theories on tannin use as a potential additive to semen extenders, its relationship with semen quality, and to what degree existing theories have been investigated to develop testable new hypotheses. Emphasis was placed on the effects of tannins on ROS, their involvement in regulating sperm structure and function during cryopreservation, and on post-thaw sperm motility, capacitation, and fertilising ability. The diverse effects of tannins on the reproductive system as a result of their potential metal ion chelation, protein precipitation, and biological antioxidant abilities have been identified. The current data are the first to support the further investigation of the incorporation of tannin-rich plant extracts into semen extenders to enhance the post-thaw survival, motility, and fertilising ability of cryopreserved spermatozoa.

Toxicological Evaluation of a Polyherbal Formulation on Testicular Function and Gonadal Histomorphology in Exposed Wistar Rats

“…For instance, Onyejike et al [ 19 ] reported that the herbal mixture contains tannins, saponins and flavonoids, and these plant chemicals are known to impact spermatogenesis. A typical example is tannins extracted from Z. officinale (a plant composition of the product) which have been reported to increase sperm parameters [ 20 ]. Despite the recorded significant increase in total sperm cell count of exposed male rats, the significant decrease in actively motile sperm cells, normal morphology as well as increase in non-motile sperm cells might indicate adverse exposure-associated effects of the polyherbal mixture.…”

Bioprotective Role of Phytocompounds Against the Pathogenesis of Non-alcoholic Fatty Liver Disease to Non-alcoholic Steatohepatitis: Unravelling Underlying Molecular Mechanisms

“…Tannins are a diverse range of large-molecular-weight, watersoluble chemicals found naturally in various fruits, grains, and vegetables [193]. Tannins, potent antioxidant substances, serve as scavengers preventing harmful ROS effects [194]. Therefore, the compounds belonging to the tannin class with anti-NAFLD characteristics are enlisted in this section and outlined in ▶ Fig.…”

Protection of Myrmecodia Extract in Tris Diluent on PO Bull Sperm Quality During Freezing

“…Indicate protection of tannin-containing buffers from potential and active MYE during freezing and storage processes. The results of a study by Liman et al (2022) stated that tannins and their derivatives have natural protective properties that have the potential to improve the viability of sperm cells after freezing. Standar semen beku yang disyaratkan oleh SNI 4869-1:2021, motilitas sperma PTM > 40%.…”