Effects of chlorogenic acid (CGA) supplementation during in vitro maturation culture on the development and quality of porcine embryos with electroporation treatment after in vitro fertilization

Do the hormetic effects of chlorogenic acid mediate some of the beneficial effects of coffee?

The present paper provides the first documentation and assessment of the capacity of chlorogenic acid to induce hormetic dose-response relationships. The findings suggest that chlorogenic acid may induce anabolic (i.e., growth) and catabolic (i.e., protective) hormetic dose responses in several cell types via a range of complementary and cross-talking pathways, affecting a spectrum of endpoints of biomedical and therapeutic importance. This paper also addresses the issue of whether the widely recognized beneficial effects of coffee consumption, as reported in multiple epidemiological studies, may be related to the hormetic effects of chlorogenic acid and its metabolites and their interactions. The present analysis suggests that some beneficial effects of coffee consumption may be due to the effects of chlorogenic acid and/or its metabolites on the gastrointestinal tract via their capacity to impact gastrointestinal integrity, structure, and functionality. These effects collectively contribute to the attenuation of the gastrointestinal tract and concurrent systemic oxidative stress, positively affecting a range of organ-specific effects.

Bioactive functions of chlorogenic acid and its research progress in pig industry

Chlorogenic acid (CGA), also known as 3-caffeioylquinic acid or coffee tannin, is a water-soluble polyphenol phenylacrylate compound produced through the shikimate pathway by plants during aerobic respiration. CGA widely exists in higher dicotyledons, ferns and many Chinese medicinal materials, and enjoys the reputation of 'plant gold'. Here, we summarized the source, chemical structure, biological activity functions of CGA and its research progress in pigs, aiming to provide a more comprehensive understanding and theoretical basis for the prospect of CGA replacing antibiotics as a pig feed additive.

The Effects of an In Vitro Oocyte Maturation System and Chlorogenic Acid Supplementation during Embryo Culture on the Development of Porcine Cloned Embryos Derived from Native Vietnamese Ban Pigs

The aim of this study was to improve the production efficiency of Vietnamese native Ban pig embryos using somatic cell nuclear transfer (SCNT). Fibroblast cells from Ban pigs were injected into the enucleated cytoplasts of crossbred gilts, and the reconstructed embryos were subsequently cultured. In the first experiment, cytoplasts were isolated from oocytes matured in either a defined porcine oocyte medium (POM) or in TCM199 medium supplemented with porcine follicular fluid. Both media were supplemented with gonadotropic hormones, either for the first 22 h of in vitro maturation (IVM) or for the entire 44 h of IVM. In the second experiment, the reconstructed SCNT embryos were cultured with or without 50 μM chlorogenic acid (CGA). Furthermore, this study examined parthenogenetic embryos. The IVM medium and duration of hormone treatment did not affect embryo development. CGA supplementation to the culture medium significantly increased blastocyst formation rates in parthenogenetic embryos but not in SCNT embryos. However, CGA supplementation significantly reduced the apoptotic index in blastocysts regardless of embryo source. In conclusion, the IVM method did not affect SCNT embryo production, while CGA supplementation during embryo culture improved the quality of SCNT embryos in indigenous pig breeds.

Chlorogenic acid improves functional potential of follicles in mouse whole ovarian tissues in vitro

BACKGROUND

Chlorogenic acid (CGA) is one of the well-known polyphenol compounds possessing several important biological and therapeutic functions. In order to optimize a culture system to achieve complete development of follicles, we focused on the effects of CGA supplementation during in vitro culture (IVC) on follicular development, oxidative stress, antioxidant capacity, developmental gene expression, and functional potential in cultured mouse ovarian tissue.

METHODS AND RESULTS

The collected whole murine ovaries were randomly divided into four groups: (1) non-cultured group (control 1) with 7-day-old mouse ovaries, (2) non-cultured group (control 2) with 14-day-old mouse ovaries, (3) cultured group (experimental 1) with the culture plates containing only the basic culture medium, (4) cultured group (experimental 2) with the culture plates containing basic culture medium + CGA (50, 100 and 200 µmol/L CGA). Afterward, histological evaluation, biochemical analyses, the expression assessment of genes related to follicular development and apoptosis as well as the analysis of 17-β-estradiol were performed. The results showed that supplementation of ovarian tissue with the basic culture media using CGA (100 µmol/l) significantly increased the survival, developmental and functional potential of follicles in whole mouse ovarian tissues after 7 days of culture. Furthermore, CGA (100 µmol/L) attenuated oxidative damage and enhanced the concentration of antioxidant capacity along with developmental gene expression.

CONCLUSION

It seems that supplementation of ovarian tissue with culture media using CGA could optimize follicular growth and development in the culture system.

Protective effects of chlorogenic acid against ionizing radiation-induced testicular toxicity

Background

Testicular tissues could damage by ionizing radiation (IR) during the treatment of pelvic cancers. The aim of this study was to investigate both the protective and therapeutic effects of chlorogenic acid (CGA) on IR-induced mouse testis tissue damage.

Methods

In this experimental study, 70 mice were divided into 3 groups, including group 1 (normal saline), group 2 (IR + normal saline), and group 3 (IR + 5, 10, 20, 40, and 80 mg/kg) CGA via I.P injection. Animals in groups 2 and 3 received a dose of 2.0 Gy total-body irradiation in a single fraction. At two determined time points (16 h and 35 days after exposure), the testis and caudal part of both epididymis were isolated and underwent subsequent analyses.

Results

The results showed that irradiation of mice caused massive damage to spermatogenesis, seminiferous tubules, basal lamina, Leydig cells, and sperm parameters. Further biochemical assessment of the data demonstrated that 40 mg/kg CGA almost restored MDA to a normal level. In addition, the level of SOD, TAC, and GSH were significantly increased in the 40 mg/kg CGA treated group. Molecular evidence confirmed the protective effects of CGA and also revealed that the ratio of Bax/Bcl-2 in the presence of 40 mg/kg CGA was significantly decreased compared to IR and some treated groups.

Conclusion

The protective and therapeutic effects of CGA on testis were found to be positively correlated with the dose level.

Effects of individual or in-combination antioxidant supplementation during in vitro maturation culture on the developmental competence and quality of porcine embryos

The oocyte maturation process requires a high supply of energy, which generates reactive oxygen species (ROS), adversely affecting oocyte and embryo development. Balancing ROS by antioxidant supplementation is essential for maintaining oocyte maturation and embryonic quality in vitro. This study aimed to evaluate the impact of four antioxidants: β-mercaptoethanol (β-ME), chlorogenic acid (CGA), curcumin and sericin, when applied individually or in combinations, during oocyte maturation on development of porcine oocytes. Cumulus-oocyte complexes were collected, cultured in maturation medium supplemented with antioxidants for 44 hr and subsequently subjected to in vitro fertilization (IVF) and culture for 7 days. Combining all four (β-ME + CGA + curcumin + sericin) or three (β-ME + CGA + curcumin) antioxidants increased blastocyst formation rates. However, sericin supplementation alone, or in combination with β-ME or CGA, failed to improve blastocyst formation rates. The total cell numbers of blastocysts from the group supplemented with three antioxidants (β-ME + CGA + curcumin) were significantly higher than those from the other groups, except for the curcumin-supplement group. There were no differences in the maturation rates and proportions of oocytes with fragmented DNA between the antioxidant-supplemented and the non-supplemented control groups. In conclusion, supplementation with three antioxidants (β-ME + CGA + curcumin) during the maturation culture enhanced blastocyst formation and improved blastocyst quality.

Presence of chlorogenic acid during in vitro maturation protects porcine oocytes from the negative effects of heat stress

Chlorogenic acid (CGA) is known to protect oocytes from oxidative stress. Here we investigated the effects of CGA on porcine oocyte maturation under heat stress and subsequent embryonic development after parthenogenetic activation. For in vitro maturation (IVM) at 41.0°C (hyperthermic condition), supplementation of the maturation medium with 50 μM CGA significantly improved the percentage of matured oocytes and reduced the rate of apoptosis relative to oocytes matured without CGA (p < .05). CGA treatment of oocytes during IVM under hyperthermia tended to increase (p < .1) percentage of blastocyst formation after parthenogenesis and significantly increased (p < .05) the total cell number per blastocyst relative to oocytes matured without CGA. For IVM at 38.5°C (isothermic condition), CGA significantly improved the rate of blastocyst development compared with oocytes matured without CGA (p < .05), but did not affect oocyte maturation, apoptosis rate or the number of cells per embryo. Omission of all antioxidants from the IVM medium significantly reduced the rate of oocyte maturation, but the rate was restored upon addition of CGA. These results demonstrate that CGA is a potent antioxidant that protects porcine oocytes from the negative effects of heat stress, thus reducing the frequency of apoptosis and improving the quality of embryos.

Oxidative homeostasis in oocyte competence for in vitro embryo development

The objective of this study was to evaluate the levels of reactive oxygen species (ROS) and glutathione (GSH) in oocytes from follicles of different diameters and their relevance in the in vitro production of embryos (IVPE). Bovine ovaries were aspirated according to the diameter of the follicle [2-8 (general), 4-8 (large), and 2 < 4 mm (small)]. The oocytes were evaluated for levels of ROS, GSH, in vitro maturation, and IVPE. Higher levels of ROS and GSH were observed (p < 0.05) in oocytes of the large group (85.6 ± 7.2 and 140.0 ± 9.6) followed by those in the general (81.1 ± 10.5 and 134.3 ± 7.8) and small (73.5 ± 10.1 and 125.0 ± 10.6) groups. However, the proportion of ROS/GSH did not differ (p > 0.05) between the general, large, and small groups. The maturation was higher (p < 0.05) in the large group (87.8 ± 3.0%) than in the small group (72.2 ± 5.8%), but both were similar (p > 0.05) to that in the general group (82.2 ± 2.5%), whereas the IVPE of the large group (57.3 ± 3.0%) was higher (p < 0.05) than those in the general (44.7 ± 4.4%) and small (34.0 ± 4.0%) groups. We report that oocytes from large follicles are more competent for IVPE, whereas higher levels of ROS and GSH appear to be correlated with oocyte competence, as long as oxidative homeostasis is retained.