Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic informat... more Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic information on these abnormalities must be generated. Objectives To characterize the metabolic changes associated with elevated fructosamine, reflecting poor glycemic control, and low thyroxine, a thyroid hormone controlling metabolism. Methods Leftovers of clinical serum samples; 25 controls, 79 high fructosamine, and 47 low thyroxine, were analyzed using 1H NMR and differences were evaluated using Firth logistic regression. Results Both high fructosamine and low thyroxine were associated with changes in concentrations of multiple metabolites, including glycoprotein acetyls and lipids. Conclusion These findings suggest promising makers for further research and clinical validation.
The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility i... more The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility is not fully understood. We used the downregulated testis as a model of gonadotropin-dependent infertility. Serum testosterone and AMH concentrations were studied in five adult male Beagles implanted (day 0) with 4.7 mg deslorelin (Suprelorin®, Virbac) (DES group). Testicular expression of LH receptor (LHR) and androgen receptor (AR), AMH, type 2 AMH receptor (AMHR2), INSL3 and its receptor (RXFP2) was evaluated 112 days (16 weeks) after deslorelin treatment by qPCR and immunohistochemistry, and compared to untreated adult (CON, n = 6) and prepubertal (PRE, n = 8) dogs. Serum testosterone concentration decreased significantly by the onset of aspermia on study day 14 (four dogs) or day 21 (one dog), and was baseline on day 105 (week 15). In contrast, serum AMH started to increase only after the onset of aspermia and reached the maximum detectable concentration of the assay by day 49-105 in individual dogs. Testicular LHR gene expression in DES was lower than in CON and PRE (P < 0.0001), while AR gene expression in DES was similar to CON and significantly higher than PRE (P < 0.0001). Testicular AMH expression in DES was intermediate compared to the lowest mRNA levels found in CON and the highest in PRE (P ≤ 0.006). AMHR2 gene expression was similar between groups. AMH protein was detected in Sertoli cells only, while AMHR2 immunoreactivity was principally detected in Leydig cells which appeared to be increased in DES. INSL3 and RXFP2 gene expression was significantly downregulated in the DES testis along with noticeably weak Leydig cell immunosignals compared to CON. In conclusion, deslorelin treatment caused testicular LH insensitivity without affecting androgen sensitivity, and de-differentiation of Sertoli and Leydig cells. In DES, upregulation of the AMH-AMHR2 feed-back loop and downregulation of the INSL3-RXFP2 feed-forward loop are paracrine-autocrine mechanisms that may additionally regulate testosterone production independent of gonadotropins. Our results support AMH and INSL3 as unique biomarkers and paracrine-autocrine regulators of testis function involved in the intimate interplay between Sertoli and Leydig cells.
Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an ei... more Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an eine Laboruntersuchung ist es, die zugrunde liegende Fragestellung möglichst konkret zu beantworten. Dies ist unabhängig davon, ob die Probe im praxis- bzw. klinikeigenen oder aber in einem Versandlabor untersucht wird. Die Messergebnisse sollten die physiologische bzw. pathologische Situation des Tieres zum Zeitpunkt der Probennahme möglichst genau widerspiegeln. Der Beitrag informiert darüber, was es zu beachten gibt.
Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic informat... more Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic information on these abnormalities must be generated. Objectives To characterize the metabolic changes associated with elevated fructosamine, reflecting poor glycemic control, and low thyroxine, a thyroid hormone controlling metabolism. Methods Leftovers of clinical serum samples; 25 controls, 79 high fructosamine, and 47 low thyroxine, were analyzed using 1H NMR and differences were evaluated using Firth logistic regression. Results Both high fructosamine and low thyroxine were associated with changes in concentrations of multiple metabolites, including glycoprotein acetyls and lipids. Conclusion These findings suggest promising makers for further research and clinical validation.
The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility i... more The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility is not fully understood. We used the downregulated testis as a model of gonadotropin-dependent infertility. Serum testosterone and AMH concentrations were studied in five adult male Beagles implanted (day 0) with 4.7 mg deslorelin (Suprelorin®, Virbac) (DES group). Testicular expression of LH receptor (LHR) and androgen receptor (AR), AMH, type 2 AMH receptor (AMHR2), INSL3 and its receptor (RXFP2) was evaluated 112 days (16 weeks) after deslorelin treatment by qPCR and immunohistochemistry, and compared to untreated adult (CON, n = 6) and prepubertal (PRE, n = 8) dogs. Serum testosterone concentration decreased significantly by the onset of aspermia on study day 14 (four dogs) or day 21 (one dog), and was baseline on day 105 (week 15). In contrast, serum AMH started to increase only after the onset of aspermia and reached the maximum detectable concentration of the assay by day 49-105 in individual dogs. Testicular LHR gene expression in DES was lower than in CON and PRE (P < 0.0001), while AR gene expression in DES was similar to CON and significantly higher than PRE (P < 0.0001). Testicular AMH expression in DES was intermediate compared to the lowest mRNA levels found in CON and the highest in PRE (P ≤ 0.006). AMHR2 gene expression was similar between groups. AMH protein was detected in Sertoli cells only, while AMHR2 immunoreactivity was principally detected in Leydig cells which appeared to be increased in DES. INSL3 and RXFP2 gene expression was significantly downregulated in the DES testis along with noticeably weak Leydig cell immunosignals compared to CON. In conclusion, deslorelin treatment caused testicular LH insensitivity without affecting androgen sensitivity, and de-differentiation of Sertoli and Leydig cells. In DES, upregulation of the AMH-AMHR2 feed-back loop and downregulation of the INSL3-RXFP2 feed-forward loop are paracrine-autocrine mechanisms that may additionally regulate testosterone production independent of gonadotropins. Our results support AMH and INSL3 as unique biomarkers and paracrine-autocrine regulators of testis function involved in the intimate interplay between Sertoli and Leydig cells.
Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an ei... more Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an eine Laboruntersuchung ist es, die zugrunde liegende Fragestellung möglichst konkret zu beantworten. Dies ist unabhängig davon, ob die Probe im praxis- bzw. klinikeigenen oder aber in einem Versandlabor untersucht wird. Die Messergebnisse sollten die physiologische bzw. pathologische Situation des Tieres zum Zeitpunkt der Probennahme möglichst genau widerspiegeln. Der Beitrag informiert darüber, was es zu beachten gibt.
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