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William J Schwartz MD

TitleAdjunct Professor
InstitutionUMass Chan Medical School
AddressUMass Chan Medical School
55 Lake Avenue North
Worcester MA 01655
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    Other Positions
    InstitutionT.H. Chan School of Medicine
    DivisionStroke and Vascular Neurology

    Collapse Biography 
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    University of California, Irvine, Irvine, CA, United StatesBSBiological Sciences
    University of California, San Francisco, San Francisco, CA, United StatesMD

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    William J. Schwartz received his M.D. (1974) and neurology residency training (1978-1981) at the University of California, San Francisco, completed a research fellowship at the National Institute of Mental Health (1975-1978), and was on the faculties of Harvard Medical School and the Massachusetts General Hospital (1981-1986) before moving to the University of Massachusetts. Visiting Professorships have included the Boerhaave Professor at Leiden University Medical Centre (2005) and the Baerends Visiting Chair at Rijksuniversiteit Groningen (2008), both in the Netherlands; and the Hood Fellow at the University of Auckland (2012), in New Zealand.

    Dr. William Schwartz, M.D.

    On the Neurobiology of Circadian Timekeeping

    Daily rhythms of physiology and behavior are governed by an endogenous timekeeping mechanism (a circadian "clock"), with the alternation of environmental light and darkness synchronizing (entraining) these rhythms to the natural day-night cycle. Our knowledge of circadian timekeeping of animals at the molecular and cellular levels is remarkable, and laboratories here in the Department of Neurobiology are playing major roles in these advances (Emery, Reppert, Weaver). This laboratory is focused at the tissue, organismal, and even supra-organismal levels of analysis, and how all levels of biological organization contribute to the emergent properties and increased complexity of the circadian system as a whole.

    Much of our work has focused on the suprachiasmatic nucleus (SCN) of the hypothalamus, the "master" circadian pacemaker of mammals, a tissue composed of multiple autonomous single-cell circadian oscillators (Figs 1 - 3). Our interests have included functional localization and energy metabolism, light-induced and endogenous gene expression, and the underyling dual oscillatory structure of the circadian pacemaker. We have been using molecular tools to show that some well-known circadian behaviors (e.g., "splitting," "forced desynchronization," and perhaps photoperiodism) emerge at the tissue level, in the dynamic interactions between SCN neurons rather than in the expression of "clock genes" within neurons.

    For the most part, experiments on circadian rhythmicity (including our own) have been carried out using singly-housed animals in plastic cages with temperature, humidity, and access to food rigidly controlled. Of course, many species ordinarily would not live out their lives in such seclusion. They form real ecological communities, and some live in colonies with highly developed social structures and a clear division of labor, requiring modifications to daily rhythms. For other animals living in the wild, social factors might act to synchronize their behaviors to achieve common goals or, alternatively, actively avoid each other to lessen competition for limited resources. We have been asking if the circadian system is involved in the inter-individual temporal adaptations of cohabiting animals and what mechanisms might be responsible (e.g., whether social interactions alter the rhythmicity of animals with genetically-defective clocks, and the identification of the neurobiological substrates (molecules, cells, and pathways) that underlie circadian adaptation to complex habitats).

    Figure 1. Coronal Nissl-stained section through the rat forebrain, including the bilaterally paired SCN (arrow).

    Figure 1. Coronal Nissl-stained section through the rat forebrain, including the bilaterally paired SCN (arrow).

    . Immunohistochemical arginine vasopressin (AVP) and vasoactive intestinal polypeptide (VIP) protein expression in a coronal section of the rat SCN, processed for double-label immunofluorescence and viewed using excitation wavelengths of 488 nm (green, for AVP) and 568 nm (red, for VIP).

    Figure 2. Immunohistochemical arginine vasopressin (AVP) and vasoactive intestinal polypeptide (VIP) protein expression in a coronal section of the rat SCN, processed for double-label immunofluorescence and viewed using excitation wavelengths of 488 nm (green, for AVP) and 568 nm (red, for VIP).

    Figure 3. The SCN exhibits endogenous day-night rhythms in energy metabolism, gene expression, and electrophysiological activity.

    Figure 3. The SCN exhibits endogenous day-night rhythms in energy metabolism, gene expression, and electrophysiological activity.

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    Rotation projects are available for students using a range of experimental approaches, including small animal stereotaxic neurosurgical procedures, longitudinal behavioral analyses, histochemical and autoradiographic imaging of neural patterns of protein and gene expression, and confocal microscopy. Contact the lab regarding specific interests and projects.

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    Publications listed below are automatically derived from MEDLINE/PubMed and other sources, which might result in incorrect or missing publications. Faculty can login to make corrections and additions.
    Newest   |   Oldest   |   Most Cited   |   Most Discussed   |   Timeline   |   Field Summary   |   Plain Text
    PMC Citations indicate the number of times the publication was cited by articles in PubMed Central, and the Altmetric score represents citations in news articles and social media. (Note that publications are often cited in additional ways that are not shown here.) Fields are based on how the National Library of Medicine (NLM) classifies the publication's journal and might not represent the specific topic of the publication. Translation tags are based on the publication type and the MeSH terms NLM assigns to the publication. Some publications (especially newer ones and publications not in PubMed) might not yet be assigned Field or Translation tags.) Click a Field or Translation tag to filter the publications.
    1. Yamaguchi Y, Maekawa Y, Kabashima K, Mizuno T, Tainaka M, Suzuki T, Dojo K, Tominaga T, Kuroiwa S, Masubuchi S, Doi M, Tominaga K, Kobayashi K, Yamagata S, Itoi K, Abe M, Schwartz WJ, Sakimura K, Okamura H. An intact pituitary vasopressin system is critical for building a robust circadian clock in the suprachiasmatic nucleus. Proc Natl Acad Sci U S A. 2023 Oct 24; 120(43):e2308489120. PMID: 37844254.
      Citations:    Fields:    Translation:Animals
    2. Evans JA, Schwartz WJ. On the origin and evolution of the dual oscillator model underlying the photoperiodic clockwork in the suprachiasmatic nucleus. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2023 Jul 23. PMID: 37481773.
      Citations: 1     Fields:    
    3. Bilu C, Einat H, Zimmet P, Vishnevskia-Dai V, Schwartz WJ, Kronfeld-Schor N. Beneficial effects of voluntary wheel running on activity rhythms, metabolic state, and affect in a diurnal model of circadian disruption. Sci Rep. 2022 02 14; 12(1):2434. PMID: 35165331.
      Citations: 4     Fields:    Translation:Animals
    4. Li Y, Schwartz WJ, Indic P. Dynamics of periodically forced finite N-oscillators, with implications for the social synchronization of animal rest-activity rhythms. Chaos. 2020 Oct; 30(10):103106. PMID: 33138456.
      Citations:    Fields:    Translation:Animals
    5. Schwartz WJ. From Generation to Generation. J Biol Rhythms. 2020 02; 35(1):3. PMID: 32013728.
      Citations:    Fields:    
    6. Schwartz WJ, Klerman EB. Circadian Neurobiology and the Physiologic Regulation of Sleep and Wakefulness. Neurol Clin. 2019 08; 37(3):475-486. PMID: 31256784.
      Citations: 16     Fields:    Translation:HumansAnimals
    7. Wang S, Herzog ED, Kiss IZ, Schwartz WJ, Bloch G, Sebek M, Granados-Fuentes D, Wang L, Li JS. Inferring dynamic topology for decoding spatiotemporal structures in complex heterogeneous networks. Proc Natl Acad Sci U S A. 2018 09 11; 115(37):9300-9305. PMID: 30150403.
      Citations: 13     Fields:    
    8. Braun MC, Castillo-Ruiz A, Indic P, Jung DY, Kim JK, Brown RH, Swoap SJ, Schwartz WJ. Defective daily temperature regulation in a mouse model of amyotrophic lateral sclerosis. Exp Neurol. 2019 01; 311:305-312. PMID: 30031021.
      Citations: 1     Fields:    Translation:HumansAnimals
    9. Castillo-Ruiz A, Indic P, Schwartz WJ. Time management in a co-housed social rodent species (Arvicanthis niloticus). Sci Rep. 2018 01 19; 8(1):1202. PMID: 29352256.
      Citations: 3     Fields:    Translation:Animals
    10. Schwartz WJ. Embodied Clocks. J Biol Rhythms. 2017 12; 32(6):503-504. PMID: 29249193.
      Citations:    Fields:    Translation:AnimalsCells
    11. Helm B, Visser ME, Schwartz W, Kronfeld-Schor N, Gerkema M, Piersma T, Bloch G. Two sides of a coin: ecological and chronobiological perspectives of timing in the wild. Philos Trans R Soc Lond B Biol Sci. 2017 Nov 19; 372(1734). PMID: 28993490.
      Citations: 49     Fields:    
    12. Schwartz WJ, Helm B, Gerkema MP. Wild clocks: preface and glossary. Philos Trans R Soc Lond B Biol Sci. 2017 11 19; 372(1734). PMID: 28993501.
      Citations: 8     Fields:    Translation:Animals
    13. Schwartz WJ. On the Shoulders of Giants. J Biol Rhythms. 2017 10; 32(5):379. PMID: 29134892.
      Citations:    Fields:    
    14. Brown RH, Schwartz WJ. David A. Drachman, MD (1932-2016). Neurology. 2017 03 07; 88(10):928-929. PMID: 28265038.
      Citations:    Fields:    
    15. Schwartz WJ. Thirty Years. J Biol Rhythms. 2016 Feb; 31(1):3. PMID: 26759427.
      Citations:    Fields:    
    16. Paul MJ, Indic P, Schwartz WJ. Social synchronization of circadian rhythmicity in female mice depends on the number of cohabiting animals. Biol Lett. 2015 Jun; 11(6):20150204. PMID: 26063754.
      Citations: 10     Fields:    Translation:Animals
    17. Schwartz WJ. Body clocks. J Biol Rhythms. 2015 Feb; 30(1):3-4. PMID: 25637643.
      Citations:    Fields:    Translation:HumansAnimals
    18. Leise TL, Indic P, Paul MJ, Schwartz WJ. Wavelet meets actogram. J Biol Rhythms. 2013 Feb; 28(1):62-8. PMID: 23382592.
      Citations: 23     Fields:    Translation:Animals
    19. Gu C, Liu Z, Schwartz WJ, Indic P. Photic desynchronization of two subgroups of circadian oscillators in a network model of the suprachiasmatic nucleus with dispersed coupling strengths. PLoS One. 2012; 7(5):e36900. PMID: 22615838.
      Citations: 6     Fields:    Translation:AnimalsCells
    20. Schwartz WJ, Tavakoli-Nezhad M, Lambert CM, Weaver DR, de la Iglesia HO. Distinct patterns of Period gene expression in the suprachiasmatic nucleus underlie circadian clock photoentrainment by advances or delays. Proc Natl Acad Sci U S A. 2011 Oct 11; 108(41):17219-24. PMID: 21969555.
      Citations: 26     Fields:    Translation:Animals
    21. Paul MJ, Schwartz WJ. Circadian rhythms: how does a reindeer tell time? Curr Biol. 2010 Mar 23; 20(6):R280-2. PMID: 20334837.
      Citations: 1     Fields:    Translation:Animals
    22. Schwartz WJ. Circadian rhythms: a tale of two nuclei. Curr Biol. 2009 Jun 09; 19(11):R460-2. PMID: 19515356.
      Citations: 7     Fields:    Translation:Animals
    23. Paul MJ, Galang J, Schwartz WJ, Prendergast BJ. Intermediate-duration day lengths unmask reproductive responses to nonphotic environmental cues. Am J Physiol Regul Integr Comp Physiol. 2009 May; 296(5):R1613-9. PMID: 19225143.
      Citations: 11     Fields:    Translation:Animals
    24. Low HP, Gr?co B, Tanahashi Y, Gallant J, Jones SN, Billings-Gagliardi S, Recht LD, Schwartz WJ. Embryonic stem cell rescue of tremor and ataxia in myelin-deficient shiverer mice. J Neurol Sci. 2009 Jan 15; 276(1-2):133-7. PMID: 18996543.
      Citations: 5     Fields:    Translation:AnimalsCells
    25. Mitome M, Low HP, Lora Rodriguez KM, Kitamoto M, Kitamura T, Schwartz WJ. Neuronal differentiation of EGF-propagated neurosphere cells after engraftment to the nucleus of the solitary tract. Neurosci Lett. 2008 Oct 31; 444(3):250-3. PMID: 18761057.
      Citations: 1     Fields:    Translation:AnimalsCells
    26. Indic P, Schwartz WJ, Paydarfar D. Design principles for phase-splitting behaviour of coupled cellular oscillators: clues from hamsters with 'split' circadian rhythms. J R Soc Interface. 2008 Aug 06; 5(25):873-83. PMID: 18077247.
      Citations: 12     Fields:    Translation:Animals
    27. Paul MJ, Zucker I, Schwartz WJ. Tracking the seasons: the internal calendars of vertebrates. Philos Trans R Soc Lond B Biol Sci. 2008 Jan 27; 363(1490):341-61. PMID: 17686736.
      Citations: 59     Fields:    Translation:Animals
    28. Indic P, Schwartz WJ, Herzog ED, Foley NC, Antle MC. Modeling the behavior of coupled cellular circadian oscillators in the suprachiasmatic nucleus. J Biol Rhythms. 2007 Jun; 22(3):211-9. PMID: 17517911.
      Citations: 11     Fields:    Translation:HumansAnimals
    29. de la Iglesia HO, Schwartz WJ. Minireview: timely ovulation: circadian regulation of the female hypothalamo-pituitary-gonadal axis. Endocrinology. 2006 Mar; 147(3):1148-53. PMID: 16373412.
      Citations: 61     Fields:    Translation:HumansAnimalsCells
    30. Tavakoli-Nezhad M, Schwartz WJ. c-Fos expression in the brains of behaviorally "split" hamsters in constant light: calling attention to a dorsolateral region of the suprachiasmatic nucleus and the medial division of the lateral habenula. J Biol Rhythms. 2005 Oct; 20(5):419-29. PMID: 16267381.
      Citations: 20     Fields:    Translation:Animals
    31. Silver R, Schwartz WJ. The suprachiasmatic nucleus is a functionally heterogeneous timekeeping organ. Methods Enzymol. 2005; 393:451-65. PMID: 15817305.
      Citations: 33     Fields:    Translation:AnimalsCells
    32. Schwartz WJ. Sunrise and sunset in fly brains. Nature. 2004 Oct 14; 431(7010):751-2. PMID: 15483589.
      Citations: 1     Fields:    Translation:AnimalsCells
    33. de la Iglesia HO, Meyer J, Schwartz WJ. Using Per gene expression to search for photoperiodic oscillators in the hamster suprachiasmatic nucleus. Brain Res Mol Brain Res. 2004 Aug 23; 127(1-2):121-7. PMID: 15306128.
      Citations: 8     Fields:    Translation:Animals
    34. de la Iglesia HO, Cambras T, Schwartz WJ, D?ez-Noguera A. Forced desynchronization of dual circadian oscillators within the rat suprachiasmatic nucleus. Curr Biol. 2004 May 04; 14(9):796-800. PMID: 15120072.
      Citations: 94     Fields:    Translation:AnimalsCells
    35. de la Iglesia HO, Meyer J, Schwartz WJ. Lateralization of circadian pacemaker output: Activation of left- and right-sided luteinizing hormone-releasing hormone neurons involves a neural rather than a humoral pathway. J Neurosci. 2003 Aug 13; 23(19):7412-4. PMID: 12917377.
      Citations: 53     Fields:    Translation:AnimalsCells
    36. Van Gelder RN, Herzog ED, Schwartz WJ, Taghert PH. Circadian rhythms: in the loop at last. Science. 2003 Jun 06; 300(5625):1534-5. PMID: 12791982.
      Citations: 9     Fields:    Translation:AnimalsCells
    37. Meijer JH, Schwartz WJ. In search of the pathways for light-induced pacemaker resetting in the suprachiasmatic nucleus. J Biol Rhythms. 2003 Jun; 18(3):235-49. PMID: 12828281.
      Citations: 79     Fields:    Translation:HumansAnimalsCells
    38. De la Iglesia HO, Schwartz WJ. A subpopulation of efferent neurons in the mouse suprachiasmatic nucleus is also light responsive. Neuroreport. 2002 May 07; 13(6):857-60. PMID: 11997701.
      Citations: 7     Fields:    Translation:AnimalsCells
    39. Zlomanczuk P, Mrugala M, de la Iglesia HO, Ourednik V, Quesenberry PJ, Snyder EY, Schwartz WJ. Transplanted clonal neural stem-like cells respond to remote photic stimulation following incorporation within the suprachiasmatic nucleus. Exp Neurol. 2002 Apr; 174(2):162-8. PMID: 11922658.
      Citations: 2     Fields:    Translation:AnimalsCells
    40. Herzog ED, Schwartz WJ. A neural clockwork for encoding circadian time. J Appl Physiol (1985). 2002 Jan; 92(1):401-8. PMID: 11744683.
      Citations: 18     Fields:    Translation:HumansAnimals
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