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seX & whY

seX & whY

Dr. Jeannette Wolfe

seX & whY explores how biological sex and gender influence our brain, body, and behavior. Dr. Jeannette Wolfe showcases some of this fascinating science to help us better understand ourselves and each other.

41 - Sex and Gender Differences in Aging
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  • 41 - Sex and Gender Differences in Aging

    Show Notes for Episode Twenty-Six of seX & whY: Sex and Gender Differences in Aging

    Host: Jeannette Wolfe Guest: Sara Haag

    Dr Haag is a researcher in molecular epidemiology who studies human biological aging at the Karolinska Institute in Stockholm.

    Background - Dr Haag has a PhD in functional genomics and Post Doc in genetic and molecular epidemiology. She studies telomeres and molecular association with telomere length, she also has experience in molecular biology and computer science.

    Definitions and discussion points from podcast

    Geroscience - a new field of biomedical science that looks at how the molecular, genetic, and cellular mechanisms associated with the aging process itself may interact and even trigger many diseases associated with aging. This research provides a different angle for potential intervention to enhance health and longevity.  Life Span - time between birth and death. Heath Span - time within life span of good health. Frailty Index and Clinical Frailty Scale are tools that evaluate a patient’s overall physical conditioning and their vulnerability to certain adverse outcomes including falls, increased care requirements, hospital admission,  and mortality.  Epigenetics - the study of how DNA expression can be modified by behavior or environmental factors (versus alteration in the actual DNA itself). One way I think of this is to imagine a huge library full of books, and that each book represents a gene coded from our DNA- epigenetics help determine which books get pulled off the shelfs and get read or pushed back deeper into the shelfs.  This process is different than buying new books for the library (which would be equivalent to changing the DNA itself.)  Aging Scales - as different elements of the body age differently, there is not a gold standard to measure aging. Dr Haag recently published a study that evaluated a bunch of these different scales and determined that the “ideal” scale will vary dependent upon what you are studying- such as overall function or the biological aging of a specific organ (i.e. heart or liver).  

    Two major theories of aging:

    Senescence theory of aging - the belief that with age, cellular systems due to repeat exposure to intracellular and extracellular stressors, eventually start to malfunction and breakdown.  Things start slowly falling apart due to wear and tear.  Programmed theory of aging - Aging is an innate active process which is highly regulated by an internal time clock. 

    As the field of Geroscience and epigenetics evolves, the “truth” around aging is likely to be a combo of both theories. 

    Sex Differences

    Hormones

    Estrogen

    Dr Haag talked about research involving telomere length (telomeres are the cap of the chromosome and they help protect the chromosomes from damage.) Typically, telomeres shorten with repeated division in somatic cells and when they shrink to a certain length the cell is more vulnerable to error and damage. Females have longer telomere length at birth compared to males and there is evidence that women with longer exposure to estrogen have longer telomeres.                   

    Testosterone

    Here is the Korean Eunuch study mentioned in the podcast.  The researchers examined a genealogical record of 385 eunuchs and compared their life span to several other groups of men who lived during the same time periods including a bunch of kings. They found that the average life span of a eunuch was 70 which was 15-19 years longer than the comparison groups. One theory behind this difference in longevity is “the disposable soma theory”. This postulates that in males there is competition between two different intrinsic systems - somatic aging and reproduction- and that as both systems require significant energy to maintain,  when energy is diverted to one system the other suffers.  

    Sex Chromosomes

    In females each cell has two X chromosomes. In female cells, one of the X chromosomes is typically inactivated so that some cells have genes expressed that are inherited by their father, while others express genes inherited from their mother. Complicating this further is that several genes do not fully inactivate that second X chromosomes so that females may have an “extra” expression of some genes. A concrete example of this is the gene Toll like receptor 7 which codes for proteins that helps the immune system recognize the early invasion of certain types of viruses. As this gene doesn’t undergo X inactivation, it may give females an extra boost in warding off certain types of viral infections. 

    With aging there can be “skewing” of the X chromosome in that females may have a disproportionate percentage of cells that express the X chromosomes of a single parent.  

    As male cells age, some may actually lose their Y chromosome. This news release suggests that his may happen relatively frequently as their work implied that 40% of all 70-year-olds had cellular evidence of it.  The loss of Y chromosome can be associated with Alzheimer’s and heart disease in males.   

    Take home points:

    1)    The field of aging is absolutely exploding. Someday it may be possible to actively manipulate epigenetic signaling to slow or even reverse aging processes.  

    2)    Different biological processes in our bodies age at different rates. Plus, if you follow a group of people over time, as they get older there will be greater and greater differences within that group in their markers of aging.

    3)    In aging research, there has historically been two different camps- the senescence camp, and the programmed theory one. In the senescence camp is the belief that as we age, things just start breaking down due to natural wear and tear. This contrasts with the programmed theory camp which believes that aging is a pre-designed active process that is triggered with age. The “truth” likely is a combination of both theories with epigenetics being the bridge. 

    4)    Sex differences in aging include the mortality-morbidity paradox in that although females tend to have poorer health and greater fragility risk, males still tend to die sooner. 

    5)    Sex differences with aging may include changes in the X chromosome with increased skewing and even the loss of the expression of the Y chromosome, both of which can be associated with an increase of health-related issues. 

    Thanks for listening. May you be well (and curious).  Jeannette.
    Wed, 29 Nov 2023 - 39min
  • 40 - Global Health and Pandemic Responsiveness Through a Sex and Gender Lens Part 2

    Show Notes for Episode Twenty-Five of seX & whY, Part 2: Global Health and Pandemic Responsiveness Through a Sex and Gender Lens

    Host: Jeannette Wolfe Guests: McKinzie Gales and Emelie Yonally Phillips

    McKinzie Gales – Global Health Fellow at the CDC and co-lead for Phase I of the multi-agency SAGER IOA project aimed at facilitating better collection, analysis, and use of sex-disaggregated data and gendered data for outbreak response.   Emelie Yonally Phillips – Global Health consultant (Epicentre/MSF) and core member of the Integrated Outbreak Analytics initiative

    Phase 1 of the sex and gender equity in research (SAGER) for Integrated Outbreak Analytics (IOA) study involved A systematic literature review to better understand what is already known about the influence of sex and gender in outbreaks and to investigate if sex-disaggregated data and gendered data is being collected, analyzed, and used. Five different databases were searched and articles meeting the inclusion criteria were included. All included articles were published in English between 2012-2022, included the key terms “sex,” “gender,” or “pregnancy,” and discussed infectious disease outbreaks (e.g., cholera, dengue, Ebola, zika, hepatitis E, Malaria, influenza, yellow fever) in a low- and middle-income countries. Notably, they intentionally excluded articles focused on covid and tuberculous as sex and gender research is being extensively conducted on these diseases. 

    Of the 15,000+ articles in their original search, only 71 articles examined potential sex and/or gender related factors associated with outbreaks in low- and middle-income countries. 

    Although currently there is very limited data on the impact that sex and/or gender play in outbreaks and pandemics, what is known, underscores the complexity of these relationships. Studying specific outbreaks in specific contexts is important because who is most likely to get infected and how rapidly an infection is spread is influenced by several intersecting factors. These include the infectious agent, sex specific immunological factors and local socio-cultural practices and norms.

    McKinzie highlighted that when there is a lack of gender and sex sensitive responses in outbreaks, evidence suggests that women, girls, and those with female anatomy are disproportionately negatively affected. For example, women are at greater risk for gender- based violence during a lock down and those with female anatomy are more directly impacted by the diversion of health care resources from clinics that offer reproductive health and pregnancy related services.

    We went through an example as to how the SAGER IOA model might work in a theoretical outbreak. In establishing a functioning multi-disciplinary team, Emelie emphasized the importance of working within local systems to build long term relationships, community trust and capacity.  She underscored how critical it was to understand the values and priorities of the individuals most impacted by the outbreak and to ensure they had a voice in decision-making. She also discussed the importance of effective and transparent community health messaging- particularly if new data suggests a change from current practice. A recent example of this was the confusion experienced by many pregnant women surrounding the safety of Ebola vaccination. 

    Emelie also spotlighted the opportunity to better understand how gender nonconforming and sexual minorities experience outbreaks as there is currently an absence of data on these groups. Finally, she emphasized that the failure of considering sex and gender specific needs in an outbreak can have tremendous downstream effects. Specifically, generational poverty, educational and professional inequities, gross domestic product, global trade, and security can all be impacted.

    One of the other interesting areas we touched upon was how personal protective equipment (PPE) and other medical related equipment was initially designed for the anatomy and physiology of a male body and may not always work for a female one. Below are a few articles on this point.

    Respiratory Personal Protective Equipment for Healthcare Workers. This study reported findings on adequate mask fitting in one hospital system’s fit test data for FF3 masks.  Their data set suggested that 18% of women had an inadequate FF3 mask fit compared to 10% of men. 

    Unions say coronavirus crisis has brought ‘into sharp focus’ the problem of women being expected to wear PPE designed for men.

    Here is a very interesting article that further explores whether medical equipment should be adjusted to better fit the anatomical variations of different users. The article - Does surgeon sex and anthropometry matter for tool usability in traditional laparoscopic surgery? makes a strong argument that most of the advances in laparoscopic surgical equipment have previously focused on accommodating different patient related factors and that their remains an opportunity to modify products to better align with anatomical characteristics of different users.  In turn, this may help enhance performance, outcome, and injury prevention of the users - AKA in this case the surgeons. 

    Thanks for listening and be well.

    Fri, 04 Aug 2023 - 23min
  • 39 - Global Health and Pandemic Responsiveness Through a Sex and Gender Lens Part 1

    Show Notes for Episode Twenty-Five of seX & whY: Global Health and Pandemic Responsiveness Through a Sex and Gender Lens

    Host: Jeannette Wolfe Guests: 

    McKinzie Gales – Fellow at the CDC and co-lead for Phase I of the multi-agency SAGER IOA project aimed at facilities' better collection, analysis, and use of sex-disaggregated data and gendered data for outbreak response.  Emelie Yonally Phillips – Global Health consultant and core member of the Integrated Outbreak Analytics initiative

     

    Definitions

    IOA - Integrated Outbreak Analytics SAGER - Sex and Gender Equity in Research 

    The Integrated Outbreak Analytics (IOA) initiative is a collaborative partnership between UNICEF, WHO, US-CDC, ITM, Epicentre, IFRC, under the umbrella of GOARN.

    The IOA concept started in earnest in 2018 during the Ebola outbreak in the Democratic Republic of Congo after it became clear that more real time, comprehensive on the ground data was needed to best manage outbreaks in an efficient and effective manner. The larger-picture concept is that the IOA model sets up a system for increased interagency data sharing and a process for data collection that produced more comprehensive information about:

    How infections spread How individuals access health systems and how patterns might evolve over time How local sociocultural norms, behaviors and expectations, impact an outbreak response and community recovery   

    The IOA - Creates a more holistic response to outbreaks along the entire pipeline from prevention to treatment. It creates a model that puts lots of partners at the table including major players like Unicef, WHO, CDC, Doctors Without Borders in addition to local governmental agencies and boots on the ground health care providers.

    Examples of data that may be integrated to provide a clearer story of what is happening in an outbreak include: 

    Surveillance data Health information systems data Programs data Community data Timeline event data Climate, weather and ecosystems data Local economy data

    Goal is to apply a multi-disciplinary approach to outbreak analyses to provide a more holistic and timely understanding of outbreak dynamics and provide local Ministries of Health and response actors with rapid evidence to make decisions during an outbreak.

    A key component of IOA is understanding the dynamics of both sex and gender within outbreaks and outbreak response for more adapted and appropriate responses. Therefore, IOA systematically works to collect, analyse and use data disaggregated by sex and inclusive of gender criteria across all phases of response:

    Prevention Detection Management/Treatment  Response

     

    Four phase project

    Phase 1:

    Systematic literature review - how are sex and gender being considered in outbreak response

    Phase 2:

    Participatory engagement in real time projects that are using an IOA and identifying what is already known about site specific sex and gender differences in tools/programs. Developing survey of response actors looking at their current understanding about sex and gender and how they are or are not collecting needed information and/or analyzing and using it to guide interventions. Create workshops and small groups to address challenges identified in survey and key informant interviews, identify capacities and brainstorm on how to overcome recognized barriers. Co-create practical recommendations and strategies to more systematically integrate sex and gender into the outbreak analysis process.

    Phase 3:

    Collate Phase 2 responses from several different outbreaks to develop a larger SAGER IOA model that can then be flexibly applied to future outbreaks.  

    Phase 4:

    Pilot testing in different outbreaks  Evaluating responses and further modification

     

    Great resources

    Half the Sky: Turning Oppression into Opportunity for Women Worldwide by Sheryl WuDunn and Nicholas Kristof  More information about the SAGER Guidelines  Link to previous podcast with Dr Shirin Heidari who was one of the fundamental drivers of developing the SAGER Guidelines.
    Thu, 08 Jun 2023 - 22min
  • 38 - Sex and Gender Differences in Conflict - Part 2

    Show Notes for Episode Twenty-Four of seX & whY: Sex and Gender Differences in Conflict, Part 2

    Host: Jeannette Wolfe Guest: Joyce Benenson, lecturer of evolutionary biology at Harvard and author of the book Warriors and Worriers

    In this podcast we continue our discussion about women interacting with each other at the workplace and how women often manage hierarchy differently than men. We got into a spirited discussion about a question posted on a female physician’s list serve querying whether women physicians want to be addressed as  “Doctor” by other staff members. (My own preference was “yes” in front of patients, and “no” once we were outside of exam rooms.) Benenson believes that when women are interacting with women who are not family, they tend to act incredibly egalitarian. This can be challenging for women in hierarchical positions and lead to a downplay of their power. This intentional buffering may not only use up a lot of cognitive energy, but it can also be a potential disadvantage in professional situations that require a clear chain of command to optimize team performance. This can put women on a professional tightrope that can be hard to balance. Ways to address this include acknowledging that this challenge is real, committing to direct communication and focusing on shared outcome goals of the entire team. Personally, I have also found it extremely helpful to humanize the other person and remind myself that most people don’t go to work with malicious intent to try and screw up another person’s day.

    Next, we talked about likeability, and Benenson shared a fascinating economics paper called: I (Don’t) Like You! But Who Cares? Gender Differences in Same Sex and Mixed Sex Teams. This paper included a series of studies in which pairs participated in games that involved economic transactions and “likeability”. In pairs where men worked with other men, “liking” their partner was not intricately related to maximizing their profits. This was not the case in teams that involved at least one woman. In these pairs, likeability increased the chance of profits and dis-likability decreased overall profits. This suggests that when interreacting with each other, men may have a greater ability to compartmentalize their professional interactions from their personal opinions.

    Next, we talked about the “tend and befriend” theory developed by Dr Shelly Taylor. This theory suggests that when stressed, that females may benefit less from a fight or flight response and more from coming together to pool resources and share childcare. Benenson’s impression is that there is little scientific evidence that this theory holds true.  She believes, contrary to the popular stereotype, that males are actually far more likely to be the communal sex and are much more likely to form intense group bonds. 

    At the end, I briefly reviewed some of the findings of a recent paper Dr Benenson published called: Self Protection as an Adaptive Female Strategy which supports the “Staying Alive Theory”. From an evolutionary perspective, behaviors that are more likely to be found in groups of males than females, such as direct competition, physical aggression, resource accumulation and risk taking, have evolved because they provide a benefit to males in optimizing their mating opportunities and reproductive fitness. The question becomes, is there a parallel evolutionary driver for females. The Staying Alive Theory is one proposal. This theory originally developed by Campbell in 1999, suggests that compared to males, females are more likely to be innately wired to avoid conflict and be more physiologically responsive to threats that can jeopardize their health. By doing so, this helps females optimize their chance of their own fitness and the survival of their own offspring.  In their paper, Benenson and her group surveyed several different areas of science to look for support of the Staying Alive Theory and here are some of their findings. 

    In humans and other mammals, females seem to consistently outlive males, this is particularly true in species in which grandmothers are more heavily involved in caring for infants. There is a health-survival paradox, however, in that although females may have greater longevity, they are also more likely to report the presence of daily symptoms and chronic illness and have higher prescription drug use. In the world of sex and gender-based medicine this phenomenon is nicely summed up with the phrase men die, women suffer. There are sex differences in most types of cancers, in fact, except for thyroid and breast cancers, males have higher incidences of most other cancers and usually have a worse prognosis after diagnosis. Compared to female, males are also more susceptible to most infectious diseases. An as an aside, when we talk about Covid, it is estimated that globally for every 10 females who have died from it, 13-15 males have. During times of global threats, females are also more likely to follow through with public health messaging such as mask wearing and hand washing Females, compared to males, have a heightened sense of pain, which may enhance self-protective behavior to avoid situations in which injury may occur such as physical arguments In general, females are more likely to have more frequent night-time awakenings, suggesting they may be more vigilant to potential night threats than male counterparts. This tendency to break up their sleep however may be compensated by higher quality length and depth of different parts of the sleep cycle. As a group, women appear to be more concerned about environmental issues and according to a recent study involving more than 32 nations and 45,000 participants, women felt a greater urgency to protect the environment and were more likely to support policies that financially invested in it. When looking at how people communicate, females were more likely to use techniques associated with politeness including smiling and tentative language that included buffering and apologizing. Although the area of nonverbal recognition shows some mixed results, overall, it appears that females are better at identifying nonverbal expressions especially those related to fear, sadness and anger.

    This is a great paper and worth a full read if you are interested in this material.

    Thanks for listening to Sex and Why! 

    Wed, 18 Jan 2023 - 29min
  • 37 - Sex and Gender Differences in Conflict - Part 1

    Show Notes for Episode Twenty-Four of seX & whY: Sex and Gender Differences in Conflict, Part 1

    Host: Jeannette Wolfe Guest: Joyce Benenson, lecturer of evolutionary biology at Harvard and author of the book Warriors and Worriers

    Here is a link to Dr Benenson’s book Warriors and Worriers

    This book dives deep into the evolutionary roots of human behavior and Dr Benenson makes a very clear and well referenced case that human males and females have evolved from slightly different playbooks.  The root of this difference is sexual selection in that adaptions and behaviors that optimize the chance that a male’s DNA gets into the next generation are slightly different than a female’s, specifically Benenson asserts that a female’s strategy relies more heavily on keeping herself and her children physically safe and healthy. Innate differences may then by amplified or attenuated by sociocultural norms and experiences that shape an individual’s “expected behavior."

    Some bullet points from her work

    Evolutionary biology focuses heavily on the behavior of non-human primates  Much of the behavior observed in other primates can also be seen in humans When studying human behavior, it can be very hard to untangle behavior rooted in biological sex versus sociocultural influence. This is because the two are tightly interwoven and even if you intentionally raise your child to be “gender blind”, the child will still be exposed to significant gendered expectations by peers and broader societal exposures.   Many of the behaviors seen in adult humans can be visibly observed by watching pre-school children.  Boys and girls (for this podcast we are concentrating on the book ends of the gender spectrum: boys/men and girls/women) typically exhibit different behaviors as children. Boys are more likely to participate in rough and tumble play and are more comfortable with hierarchy and rotating allegiances in groups. Girls prefer playing in smaller groups of two and three. Many girls find in quite difficult to participate in larger groups consisting only of females, as they feel increased pressure to effectively navigate the different relationships within that group.  Chimpanzees, like human males, are two of the few species that engage in “warfare” or systematic behavior to attack other groups of their own species. Groups of male chimpanzees that are good at this behavior enhance the survival of the rest of their group by expanding food and territory. Benenson believes some of this warfare behavior has genetically evolved into humans and that it is  further enhanced by learned sociocultural practices. Benenson has extensively studied conflict and how males and females have different evolutionary consequences to direct aggression. She strongly believes that females are wired to avoid direct conflict to optimize their physical ability to bear and rear children to their own reproductive age.

    This is Dr Benenson’s study that looked at how much time two players spent interacting with each other after the conclusion of a  competitive sports match. It showed that men typically engaged longer with their opponent than did women. She theorizes this behavior suggests that men tend to be more agile in realigning these relationships because the relationship may be needed for a future allegiance (i.e.  in war or hunting.)

    Please tune in next month for Part 2 of this series. 
    Mon, 05 Dec 2022 - 38min
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