Paper Summaries

1. This article they studied the turnover of serotonin in the brain compared to medicated and un medicated patients. Serotonin Turnover is the depletion of previously synthesized stores of serotonin. They also studied how genes affect serotonin. Turnover is elevated in unmedicated patients and is influenced by the 5 - HTT genotype. The 5 - HTT genotype is the promoter of serotonin travel through synapse. In MDD these two things play a massive role. 

David A. Barton, M. (2008, January 1). Elevated brain serotonin turnover in patients with depression. Archives of General Psychiatry. https://jamanetwork.com/journals/jamapsychiatry/article-abstract/482548

2. In this research they tested elderly people with MDD and found that certain regions of the brain changed in size, or amount of gray matter. “Prominent brain size reductions were observed in the depressed subjects in the orbitofrontal cortex bilaterally. Cortical gray matter measurements revealed significant gray matter increases in the orbitofrontal cortex, adjacent to focal trend level significant decreases of gray matter in the same region. Depressed patients also exhibited significant gray matter increases in parietal cortices, as well as the left temporal cortex.” This could be due to them using that part of their brain less, because of their diagnosis of MDD. 

Author links open overlay panelMartina Ballmaier a c, a, c, b, & depression, A. elderly. (2003, December 5). Mapping brain size and cortical gray matter changes in elderly depression. Biological Psychiatry. https://www.sciencedirect.com/science/article/pii/S0006322303009533

3. This study used 16 depressed patients, and 16 non-depressed case matched patients and used an MRI to determine the size of the left hippocampal region. It was found that depressed patients had a 19% smaller left hippocampal volume then the non depressed patients. This is the result of glucocorticoids on the hippocampus, as depressive episodes are usually associated with 40-50% increase in cortisol release.

Bremner, J. D., Search for more papers by this author, Narayan, M., Anderson, E. R., Staib, L. H., Miller, H. L., Charney, D. S., Gray, J. P., Bludau, S., Keller, J., Inagaki, M., Videbech, P., O’Brien, J. T., Young, K. A., Campbell, S., Deicken, R. F., Posener, J. A., Vythilingam, M., Nakano, T., … Mujica, R. (2000, January 1). Hippocampal volume reduction in major depression. American Journal of Psychiatry. https://ajp.psychiatryonline.org/doi/full/10.1176/ajp.157.1.115

4. In this study they found that children with parental depressive history are more likely to get depression in their lifetime. In maternal depressive history they found that the putamen was smaller, however, in paternal depressive history they found that the putamen was bigger. These high risk youths showed double the chance of getting any kind of depressive disorder. 

Author links open overlay panelDavid Pagliaccio PhD a b, a, b, c, ObjectiveChildren of parents with depression are two to three times more likely to develop major depressive disorder than children without parental history; however, Rosso, I. M., et. al. (2019, October 18). Brain volume abnormalities in youth at high risk for depression: Adolescent Brain and Cognitive Development Study. Journal of the American Academy of Child & Adolescent Psychiatry. https://www.sciencedirect.com/science/article/pii/S089085671932101X

5. This study tested the paternal effect on the brain in anxiety and depression. When the patient was shown “warmth”, as they put it in the article, there was less of a chance of the patient to feel anxious or stressed out. However, when the patient had to listen to parents making neutral or upsetting comments, this led to depressive symptoms. The areas of the brain tested were the left amygdala, bilateral insula, subgenual anterior cingulate, etc. 

Butterfield, R. D., Silk, J. S., Lee, K. H., Siegle, G. S., Dahl, R. E., Forbes, E. E., Ryan, N. D., Hooley, J. M., & Ladouceur, C. D. (2020, February 25). Parents still matter! parental warmth predicts adolescent brain function and anxiety and depressive symptoms 2 years later: Development and psychopathology. Cambridge Core. https://www.cambridge.org/core/journals/development-and-psychopathology/article/parents-still-matter-parental-warmth-predicts-adolescent-brain-function-and-anxiety-and-depressive-symptoms-2-years-later/CB84ACFAEE0D13B32346C9A2C1AA3A38

6. This study used 88 subjects in total, 44 with MDD and 44 healthy subjects. They were presented with images of people showing facial expressions. For example, sad, happy, surprised, joyful, crying, etc. In the healthy individuals they were able to correctly identify the expressions with no particular bias. However, the depressed patients were having a more difficult time identifying happier facial expressions than sad ones. 

K, G. J. et. al. (n.d.). Apa PsycNet. American Psychological Association. https://psycnet.apa.org/record/2010-21297-001

7. This is a similar study to the one above, however, in this study they took 18 patients and case matched them and showed them facial expressions. This time only including happy, sad, and neutral. The depressed patients had an easy time identifying sad, and happy emotions, but struggled when it came to identifying the neutral faces. Their reaction time to recognizing it was slower, as well as their guess of the face was very unsure. 

Author links open overlay panelJukka M. Leppänen a, a, b, c, & AbstractFunctional abnormalities in emotion-related brain systems have been implicated in depression. (2004, September 30). Depression biases the recognition of emotionally neutral faces. Psychiatry Research. https://www.sciencedirect.com/science/article/pii/S0165178104001362

8.  This paper focused on Serotonin A receptor binding in depression. The study showed that in depressed patients the binding potential of the serotonin was reduced by 26% in the mesial temporal cortex. They used PET scanning for this study, and was done on antemortem patients. Most of the other studies on this happened postmortem, which may not yield the best results. 

Author links open overlay panelWayne C. Drevets a b c, a, b, c, d, & AbstractIntroductionSerotonin-1A receptor (5-HT1AR) function appears to be decreased in major depressive disorder (MDD) based on physiological responses to 5-HT1AR agonists in vivo and to 5-HT1AR binding in brain tissues postmortem or antemortem. We have . (2007, October 5). Serotonin-1A receptor imaging in recurrent depression: Replication and Literature Review. Nuclear Medicine and Biology. https://www.sciencedirect.com/science/article/pii/S0969805107001692

9. Serotonin 1B was studied in this paper. They tested 40 healthy subjects of all different ages and genders, and studied the presence of Serotonin 1B and it was found that it decreases with age, and is something that should be considered with age.  They also examined gray matter in the brain that also showed deterioration with age. 

Matuskey, D., Pittman, B., Planeta-Wilson, B., Walderhaug, E., Henry, S., Gallezot, J.-D., Nabulsi, N., Ding, Y.-S., Bhagwagar, Z., Malison, R., Carson, R. E., & Neumeister, A. (2012, September 1). Age effects on serotonin receptor 1B as assessed by pet. Journal of Nuclear Medicine. https://jnm.snmjournals.org/content/53/9/1411.short

10. This study focused on Serotonin A and was related to aggression. Parts of the brain studied in this article were dorsal raphe, amygdala, anterior cingulate, cingulate body, medial PFC, and orbital PFC. They found that lower binding of Serotonin 1A led to more aggressive behavior. There was also a significant difference in binding sites over time in males and females.

Author links open overlay panelRamin V Parsey, AbstractSerotonin (5-HT) 1A receptors have been implicated in a variety of conditions including, Arango, V., Brown, G. L., Forster, E. A., Gozlan, H., Gunn, R. N., Haleem, D. J., Hwang, D. R., Joppa, M. A., Kates, W. R., Lammertsma, A. A., Lowther, S., Palego, L., Rabiner, E. A., Steinbusch, H. W. M., Tauscher, J., Uphouse, L., Abi-Dargham, A., … Cleare, A. J. (2002, September 21). Effects of sex, age, and aggressive traits in man on brain serotonin 5-HT1A receptor binding potential measured by pet using [c-11]way-100635. Brain Research. https://www.sciencedirect.com/science/article/abs/pii/S0006899302032432

11. This study looked at women with postpartum depression and the involvement of serotonin and homocysteine in this after birth stage. Homocysteine is an amino acid present in your body, in which if levels of this get too high symptoms can include weakness, fatigue, mood changes, etc. Lack of serotonin present in the brain is what causes PPD, and in the earlier phases of PPD this still affects it. This study tested 103 women 58 with PPD and 45 without. They did a test for PPD right after birth, and they tested the serotonin and homocysteine levels, at 24 hours after birth and then six weeks after birth. The initial test showed a spike in homocysteine in PPD, in comparison to the patients who did not have PPD. There was also more serotonin present in the patients without PPD, than patients with PPD. Although at the six week mark, homocysteine levels were still high, serotonin levels started to come back. 

S. Aishwarya a, a, b, c, AbstractPostpartum depression (PPD) is a disorder of multifactorial origin with significant consequences on both maternal and child health. One of the biological factors implicated is perturbed methionine–homocysteine metabolism. Since this metabolic path, Goedhart, G., Halbreich, U., Leung, B. M., Miyake, Y., Rouillon, F., Teissedre, F., Abou-Saleh, M. T., Adewuya, A. O., Adouard, F., Altshuler, L. L., Bottiglieri, T., Cooper, A., & Devlin, A. M. (2013, June 14). Homocysteine and serotonin: Association with postpartum depression. Asian Journal of Psychiatry. https://www.sciencedirect.com/science/article/abs/pii/S187620181300138X

12. This paper is about the effect that exercise could have on depression. Exercise has an effect on mood, and neurogenesis upregulation. Molecular advances made in this could help to learn more about brain plasticity, and better management of psychiatric disorders. This could improve depression as depression has a significant effect on neurogenesis. 

Yuan, T.-F., Paes, F., Arias-Carrión, O., Barbosa Ferreira Rocha, N., Souza de Sá Filho, A., & Machado, S. (1970, January 1). Neural mechanisms of exercise: Anti-depression, neurogenesis, and serotonin signaling. Latest TOC RSS. https://www.ingentaconnect.com/content/ben/cnsnddt/2015/00000014/00000010/art00012

13.  In this study they tested the effect of Vitamin B6 on serotonin in mice. Thirty mice that were 30 days old were tested on. They were given 4 and 10 mg/kg a day for 20 days. They found that serotonin increased partially in mice given vitamin B6, although it was a small amount it is still statistically significant because the p-value was less than 0.05. 

S. Aishwarya, Goedhart, G., Halbreich, U., Leung, B. M., Miyake, Y., Rouillon, F., Teissedre, F., Abou-Saleh, M. T., Adewuya, A. O., Adouard, F., Altshuler, L. L., Bottiglieri, T., Cooper, A., & Devlin, A. M. (2013, June 14). Homocysteine and serotonin: Association with postpartum depression. Asian Journal of Psychiatry. https://www.sciencedirect.com/science/article/abs/pii/S187620181300138X

14. In this study they tested vitamin B6 on premenstrual cycles in women , especially the period before which shows significant decrease in serotonin. In this study a group was given a placebo, and the other group was given the actual pill. The results showed no difference between the two pills. The results were statistically significant, as the p value was bigger than 0.0001. 

Malmgren, R., Collins, A., & Nilsson, C.-G. (1987). Platelet Serotonin Uptake and Effects of Vitamin B6-Treatment in Premenstrual Tension. Karger Publishers. https://karger.com/nps/article-abstract/18/2/83/230482/Platelet-Serotonin-Uptake-and-Effects-of-Vitamin

15. In this study they found a way to induce PPD behaviors into a mouse without stopping certain things like lactation. In this behavioral model, they distressed the mate and made the other one listen to its cries and then made the other mate listen to the cries. This only affected nurturing behaviors, such as licking the pups. 

Seki, T., Yamagata, H., Uchida, S., Kobayashi, A., Watanabe, Y., & Nakagawa, S. (2021, November 19). A novel mouse model of postpartum depression using emotional stress as evaluated by nesting behavior. Nature News. https://www.nature.com/articles/s41598-021-02004-9

16. This study tested the blood of 26 healthy pregnant women's blood 5 days after birth and 6 weeks after birth. They found that lower serotonin activity was found 5 days after birth than 6 weeks after. This lower serotonin level is the beginning of the PPD symptoms.  In the 6 weeks they found that 3-methoxy-4-hydroxyphenylglycol was more prevalent in the blood of the women. 

Adrien, J., Altemus, M., Bailara, K. M., Bethea, C. L., Bloch, M., Carter, C. S., Fekkes, D., Grattan, D. R., Halbreich, U., Hannah, P., Hendrick, V., Klompenhouwer, J. L., Kohl, C., Maes, M., Moleman, P., Muller-Oerlinghausen, B., Newport, D. J., Parry, B. L., Schrocksnadel, H., … Yoshimura, R. (2008, April 20). Sequential serotonin and noradrenalin associated processes involved in postpartum blues. Progress in Neuro-Psychopharmacology and Biological Psychiatry. https://www.sciencedirect.com/science/article/abs/pii/S0278584608001127

17. In this study they looked into 5-HTT which is the serotonin transporter gene. They tested 1,804 pregnant women postpartum. Tested them at  2 days, 8 weeks, and 32 weeks postpartum. They found that 173 women (12.7%) had major depression during the 32 weeks, and they also had high expression 5-HTT genotype. This means if a woman has a high expression 5-HTT genotype, they are more at risk of getting postpartum depression. 

Sanjuan, J., Martin-Santos, R., Garcia-Esteve, L., Carot, J. M., Guillamat, R., Gutierrez-Zotes, A., Gornemann, I., Canellas, F., Baca-Garcia, E., Jover, M., Navines, R., Valles, V., Vilella, E., Diego, Y. de, Castro, J. A., Ivorra, J. L., Gelabert, E., Guitart, M., Labad, A., … Frutos, R. de. (2018, January 2). Mood changes after delivery: Role of the serotonin transporter gene: The British Journal of Psychiatry. Cambridge Core. https://www.cambridge.org/core/journals/the-british-journal-of-psychiatry/article/mood-changes-after-delivery-role-of-the-serotonin-transporter-gene/A4528BCCA854A6AABF077067E8CECFAC

18. In this study 1,015 mothers were tested to see if having a colic baby would increase the likelihood of developing PPD. Most mothers reported constant crying from 2-6 months old. This test proved that mothers who had colic babies were indeed more depressed than mothers without, and even mothers who had babies that cried more than usual. These mothers showed signs of depression when their babies were 2 months, and these sy,potns were still in full effect at 4 months old.  

Vik, T., Grote, V., Escribano, J., Socha, J., Verduci, E., Fritsch, M., Carlier, C., von Kries, R., & Koletzko, B. (2009, July 1). Infantile colic, prolonged crying and maternal postnatal depresison. Wiley Online Libray. https://onlinelibrary.wiley.com/doi/10.1111/j.1651-2227.2009.01317.x

19. This study tested if exercising during pregnancy decreased the effects of PPD after birth. They evaluated 52 studies that had women in one group exercise and women in the other not. There was a significant effect of exercise on the development of PPD. 

Marconcin, P., Peralta, M., Gouveia, É. R., Ferrari, G., Carraça, E., Ihle, A., & Marques, A. (2021, December 15). Effects of exercise during pregnancy on postpartum depression: A systematic review of Meta-analyses. MDPI. https://www.mdpi.com/2079-7737/10/12/1331

20. This study tested 450 patients that have a predisposition of depression and just gave birth. They had half of the subjects exercise for 60 min everyday, and compared the results. There was a significant decrease in depressive symptoms of the group that worked out compared to the group that did not work out. On top of working out, they were eating better, practicing more self care, etc. This study was to find better ways to decrease 

Lewis, B. A., Schuver, K., Dunsiger, S., Samson, L., Frayeh, A. L., Terrell, C. A., Ciccolo, J. T., Fischer, J., & Avery, M. D. (2021, November 22). Randomized trial examining the effect of exercise and wellness interventions on preventing postpartum depression and perceived stress - BMC pregnancy and childbirth. SpringerLink. https://link.springer.com/article/10.1186/s12884-021-04257-8

21. In this study they tested mice and the effect working out had on serotonin. They had 60 minutes of swimming everyday for 4 weeks. Increase in serotonin would happen right after working out, however, there were no permanent effects. Although after one week they started to see permanent effects in the brain, as in an increase of serotonin. 

Barchas, J. D., Blundell, J. E., Coppen, A., Dishman, R. K., Fuxe, K., Hellhammer, D. H., Heyes, M. P., Moore, K. E., Parnavelas, J. G., Petty, F., Sherman, A. D., Sudo, A., Aoworth, I., Brown, B. S., Bukowiecki, L., & Chaouloff, F. (2003, February 13). Exercise training: Significance of regional alterations in serotonin metabolism of rat brain in relation to antidepressant effect of exercise. Physiology & Behavior. https://www.sciencedirect.com/science/article/abs/pii/003193849290465E

22. In this paper they looked at what happens in the body when one is depressed. An interesting aspect is a lack of tryptophan, which promotes the release of serotonin and melatonin, and a lack of this can cause depressive systems. It is also interesting because they found that a lack of tryptophan is mostly seen in depressed patients whp relapsed. 

Owens, M. J., & Nemeroff, C. B. (1994, February). Role of serotonin in the pathophysiology of depression: focus on the serotonin transporter. Academic.oup.com. https://academic.oup.com/clinchem/article-abstract/40/2/288/5647979

23. In this study they studied 4,798 females and classified them as overeaters/just eating a lot of food in general. The females that participated in binge eating showed increased symptoms of depression, they also showed that the symptoms got worse as they kept eating that way. The result was to consider depression when seeing someone binge eat, as it is highly relevant to why they are eating so much. 

Hudson, J. I., Youssef, N. N., Needham, B. L., Chen, E. Y., Goldschmidt, A. B., Grilo, C. M., Marcus, M. D., Stice, E., Neumark-Sztainer, D., Ackard, D. M., McCaffery, J. M., Qualter, P., Presnell, K., Field, A. E., Gillman, M. W., & Haines, J. (2011, December 12). A prospective study of overeating, binge eating, and depressive symptoms among adolescent and young adult women. Journal of Adolescent Health. https://www.sciencedirect.com/science/article/abs/pii/S1054139X11003430

24. In this study they looked at the effects of SSRIs on romantic attachments. Many other things go into romantic attachments other than serotonin, such as dopamine and oxytocin. They found that although SSRI’s did increase the amount of serotonin, they inhibited the other transmitters like dopamine and oxytocin. This has an effect on the relationships of the patients.

Meyer, D. (2007). Selective serotonin reuptake inhibitors and their effects on ... International Association of Marriage and Family Counselors . https://journals.sagepub.com/doi/abs/10.1177/1066480707305470

25. This study looked at 20 patients who had just fallen in love, 20 patients with OCD, and 20 control patients. They studied the 3H-par binding sites for 5-HT, and found that the density of the binding sites were lesser in the OCD patients and the people who had just fallen in love. This study suggested a connection between OCD and someone who had just freshly fallen in love, there were no other results besides a connection between the two, they did not elaborate. This is just super interesting. 

Marazziti, D., Akiskal, H. S., Rossi, A., & Cassano, G. B. (1999, May 1). Alteration of the platelet serotonin transporter in romantic love: Psychological medicine. Cambridge Core. https://www.cambridge.org/core/journals/psychological-medicine/article/alteration-of-the-platelet-serotonin-transporter-in-romantic-love/9599BA293019DFA6D05B315803B6D2A7