HYPERTHYROIDISM INCREASES MILK IMMUNE CELLS AND IMPAIRS OFFSPRING DEVELOPMENT IN EARLY LACTATION

MORENO-SOSA MARÍA TAMARA; PIETROBON, ELISA OLIVIA; VALDEZ SUSANA RUTH; SÁNCHEZ, MARÍA BELÉN; SOAJE, MARTA; JAHN, GRACIELA ALMA; NEIRA, FLAVIA JUDITH; FARIAS, HERNÁN; MACKERN-OBERTI, JUAN PABLO

Buenos Aites

Congreso; Reunión de las Sociedades de Biociencias 2020; 2020

SAIC-SAI-SAFIS

Hyperthyroidism (H) reduced milk ejection andquality, impairing maternal behavior and mammary gland development. However, itremains unclear if H impacts in milk immune cells numbers. Our aim is to assessthe influence of H on i) pup maturation and development ii) prolactin secretionand iii) milk immune cells. For this purpose, 10-12 weeks old Wistar rats were injected daily with T4(0.25 mg/kg until day 18 of gestation, then 0.1 mg/kg until day 2 oflactation L2) to induce H or with vehicle in control group. Rats were mated 8days after starting T4 treatment and euthanized L2 (afterketamine/xylazine sedation and oxytocin stimulation for milking). Afterwards,milk and mammary gland samples, minced to reach single cell suspension, were dyedwith fluorophore labeled mAbs (CD45+, CD3+, CD11b/c+)and analyzed by flow cytometry. Offspring weights on L1 and 2, headcircumference and body length (L2) were measured. Serum of dams and offspringwas obtained to determine total T4 and prolactin levels by RIA. Ourresults show that H mothers had more implantation sites and pup number (p<0,05) and higher pup mortality ratethan controls (p<0,001). The H pups had lower weight on days 1 and 2 (p<0,001), less weight gain, and diminished length and head circumference (p<0,001). H group T4 andprolactin levels were increased in dams (p<0,01;p<0,001) but T4 reduced in the pups (p<0,001). TheH group had increased % of CD45+ cells (p<0,05) and % and absolutequantity of CD3+ cells/µl compared with control while the number ofCD11 b/c+ cells was diminished (p<0,05).No changes were observed in mammary gland resident immune cells. These results suggest that T4 impairs pup development onearly lactation. Additionally, milk leukocytes are modulated by H with acell-lineage specific response. These data suggest that then maternal immuneprotection transferred through milk to the offspring may be altered in H andhighlight the need of evaluating thyroid status in pregnancy and lactation.@font-face{font-family:"Cambria Math";panose-1:2 4 5 3 5 4 6 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:-536870145 1073786111 1 0 415 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-unhide:no;mso-style-qformat:yes;mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:10.0pt;margin-left:0cm;line-height:115%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:Calibri;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;}.MsoChpDefault{mso-style-type:export-only;mso-default-props:yes;font-size:11.0pt;mso-ansi-font-size:11.0pt;mso-bidi-font-size:11.0pt;font-family:Calibri;mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:Calibri;mso-fareast-theme-font:minor-latin;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;mso-bidi-font-family:"Times New Roman";mso-bidi-theme-font:minor-bidi;mso-ansi-language:ES-AR;}.MsoPapDefault{mso-style-type:export-only;margin-bottom:10.0pt;line-height:115%;}div.WordSection1{page:WordSection1;}