abstract
Male reproductive tissues are strongly susceptible to several environmental and lifestyle stressors. In general, male reproductive health is highly sensitive to oxidative stress, which results in reversible and/or irreversible changes in testosterone-producing cells, spermatogenesis, and sperm quality. Chromium compounds are widely used in the +3 and +6 valence states, as food supplements, and in the industrial field, respectively. Chromium (III) compounds, i.e., Cr(III)-tris-picolinate, [Cr(pic)(3)], known as chromium picolinate, are used as nutritional supplements for the control of diabetes, body weight, and muscular growth. However, previous studies showed that animal models exposed to chromium picolinate experienced degenerative changes in spermatogenesis. Contradictory results are documented in the literature and deserve discussion. Furthermore, the long-term effects of chromium picolinate on the antioxidant system of treated subjects have not been properly studied. Comprehensive studies on the role of this compound will help to establish the safe and useful use of chromium supplementation. On the other hand, chromium (VI) compounds are widely used in several industries, despite being well-known environmental pollutants (i.e., welding fumes). Chromium (VI) is known for its deleterious effects on male reproductive health as toxic, carcinogenic, and mutagenic. Previous studies have demonstrated severe lesions to mouse spermatogenesis after exposure to chromium (VI). However, workers worldwide are still exposed to hexavalent chromium, particularly in electronics and military industries. Data from the literature pinpoints mechanisms of oxidative stress induced by chromium compounds in somatic and germ cells that lead to apoptosis, thus underlining the impairment of fertility potential. In this review, we analyze the benefits and risks of chromium compounds on male fertility, as well as the mechanisms underlying (in)fertility outcomes. Although supplements with antioxidant properties may maximize male fertility, adverse effects need to be investigated and discussed.
keywords
LOW-MOLECULAR-WEIGHT; PICOLINATE SUPPLEMENTATION; BODY-COMPOSITION; GLUCOSE-TOLERANCE; HUMAN-SPERMATOZOA; TRANSFERRIN RECEPTORS; TRIVALENT CHROMIUM; SPERM CAPACITATION; DIABETES-MELLITUS; BINDING SUBSTANCE
subject category
Biochemistry & Molecular Biology; Chemistry, Medicinal; Food Science & Technology
authors
Pereira, SC; Oliveira, PF; Oliveira, SR; Pereira, MD; Alves, MG
our authors
Maria de Lourdes Gomes Pereira
Associate Professor with Aggregation
Sónia M. R. Oliveira
Junior Researcheracknowledgements
This work was supported by FundacAo para a Ciencia e a Tecnologia-FCT to Sara Pereira (PTDC/MEC-AND/28691/2017); Marco G. Alves (IFCT2015 and PTDC/MEC-AND/28691/2017); LAQV-REQUIMTE (UIDB/50006/2020); UMIB (UIDB/00215/2020, and UIDP/00215/2020); ITR-Laboratory for Integrative and Translational Research in Population Health (LA/P/0064/2020); and by the Portuguese Society of Reproductive Medicine (SPMR) through the Premio Laboratorio 2020 research grant. Project CICECO-Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, national funds by FCT/MCTES are acknowledged.