May 5 , 2014 – Chemical signals and hormones V Announcements: - Final is NOT CUMULATIVE*

1. May 5, 2014 – Chemical signals and hormonesV • Announcements: • - Final is NOT CUMULATIVE* • - In lecture review session (Wed. May 7) • - TA led review session (10am – 12pm, Wed. May 14, 151 Everett Lab • Pre-lecture quiz • Review of sex hormones in males (spermatogenesis) • Sex hormones in females (menstrual cycles and pregnancy) • Hormone-mediated physiological tradeoffs • * I will ask about recurrent themes (e.g. tradeoffs, negative feedback, etc.)

2. True or False: All mammals are viviparous • A.) True • B.) False

3. Upon fertilization and implantation, the degeneration of the corpus luteum is slowed by which hormone in human females? • A.) LH • B.) Estradiol • C.) Progesterone • D.) human chorionic gonadotropin hormone (hCG)

4. Hormone-mediated TradeoffsInteractions between stress, reproduction and immune function

5. HPG axis

6. Gonads • Male testes produce sperm cells • Female ovaries produce ova • Fertilization • Sperm cell + ovum = zygote • Sex chromosomes • Humans: XX = female, XY = male • Birds: ZW = female, ZZ = male • Many vertebrates lack sex chromosomes entirely

7. Sex Hormones – Released by Gonads • Androgens - e.g., testosterone (“male” hormones) • Estrogens - e.g., estradiol (“female” hormones) • Adult testes release more androgens and ovaries more estrogens • Progestins – also present in both sexes • progesterone prepares uterus and breasts for pregnancy • Adrenal cortex – also releases sex steroids

8. HPG axis & Reproductive System Males Also known as Leydig cells

10. HPG axis & Reproductive System Females Males

11. Secondary oocyte to oviduct 5.Degeneration of corpus luteum Figure 48-12 4. Ovulation Follicle cells Oocytes 3. Maturation of follicle 1. Formation of primary oocytes within follicles 2. Follicle growth

12. FOLLICULAR PHASE LUTEAL PHASE Ovulation Corpus luteum degeneration Follicle growth Ovarian cycle Figure 48-13-2 LH Hormone levels Pituitary hormone cycle FSH 0 7 14 21 28 Days

13. FOLLICULAR PHASE LUTEAL PHASE Ovulation Corpus luteum degeneration Follicle growth Figure 48-14 Progesterone Estradiol Low Estradiol inhibits LH release Negative feedback on LH, FSH Positive feedback on LH

14. FOLLICULAR PHASE LUTEAL PHASE Corpus luteum degeneration Follicle growth Ovulation Ovarian cycle Ovarian hormone cycle Hormone levels Progesterone Figure 48-13 Estradiol LH Pituitary hormone cycle Hormone levels FSH Menstruation Thickness of uterine lining Menstrual (uterine) cycle 0 7 14 21 28 Days

15. Tons of Variation among Females. Kathryn Clancy UI - Anthropology kclancy@illinois.edu

16. Pregnancy & hormonal arrest of the menstrual cycle • Human Chorionic gonadotropin Hormone (hCG) • Secreted by the developing embryo • Slows corpus luteum degeneration • Causes the ovary to continue secreting progesterone, arresting the menstral cycle • At later stages of the pregnancy, the placenta also secretes high levels of progesterone

17. Steps of Hormonal Control of Ovarian Cycle 1. GnRh released from hypothalamus. Stimulates release of FSH/LH in ant. Pit. 2. FSH (and to a lesser extent LH) stimulates growth of follicle cells. 3. Follicle cells release E. 4. Low levels of E have negative feedback on GnRH, LH, FSH . . But follicle cells keep growing. 5. Follicle cells get big  release lots of E -- positive feedback E has a positive effects on GnRH and LH 6. Hormone surge in LH, FSH, and E. Follicle bursts  ovulation 7. burst follicle turns into corpus luteum. It secretes lots of progesterone and some estrogen. 8. increased progesterone causes thickening of endometrium. 9. P and E have a negative feedback on GnRH, LH, and FSH 10. corpus luteum degrades over time (provided no fertilized embryo) 11. P and E drop and the endometrium lining degrades (menstruation) 12. If fertilization, embryo secretes chorionic gonadotropic which maintains corpus luteum (acts like LH) and maintains high levels of P. The endometrium is maintained. The placenta develops and secretes high levels of P.

18. Hormone-mediated Tradeoffs:Interactions between stress, reproduction and immune function

19. Video 1 Testosterone treated Control

20. Video 2 Montane Urban

21. Casto JM, V Nolan Jr., ED Ketterson. 2001. Steroid hormones and immune function: experimental studies in wild and captive Dark-eyed Juncos. American Naturalist 157:408-420. Testosterone treated Control Measured: 1.) Corticosterone (= Bird cortisol) 2.) Innate Immune function (PHA injection and swelling) 3.) Adaptive Immune function (antibody production)

22. Increased testosterone is associated with elevated levels of stress hormones & a reduction in immune function

23. Testosterone treated Control

24. In adult humans, females typically exhibit a more pronounced antibody response to vaccination. Why might this be? Why might it be beneficial to vaccinate boys when they are young?

25. 1.) Females exhibited greater antibody and cytokine production following flu vaccination 2.) Antibody production was negatively associated with testosterone levels in males. 3.) Reduced immune response in males was associated with changes in the regulation of genes involved lipid metabolism and biosynthesis.

26. Video 1 Testosterone treated Control

27. Effects of cortisol on immune function • Cortisol negatively impacts: • T-cell proliferation and signaling • Leucocyte proliferation and the inflammatory response. • Development of immune system structures (i.e. thymus)