Oxidative stress is an imbalance between the production of reactive oxygen species (free radicals) and antioxidant defenses. [1] The body’s cells produce free radicals, which are nitrogen- or oxygen-containing molecules with an uneven number of electrons [2], during normal metabolic processes. [3] Meanwhile, cells also produce antioxidants that neutralize these free radicals to prevent excessive cell and tissue damage. In general, the body is able to maintain a balance between antioxidants and free radicals. [3] However, this balance could be disrupted under certain conditions or environmental stress or infection, and uncontrolled oxidative stress can accelerate the aging process.[3]
You go through everyday life thanks to the intricate communication and interaction of tissue and organ functions between the trillions of cells in your body. Within those tissues, a non-cellular component exists called the extracellular matrix (ECM). Imagine a structure made of water, proteins, and polysaccharides that helps to give structural support to surrounding cells as a connective tissue. Within the ECM lies a group of enzymes named matrix metalloproteinases (MMPs). As endopeptidases, which are enzymes that break peptide bonds, the main role of MMPs is to break down collagen and other proteins in the ECM, whether in normal tissues or in promoting cancer metastasis. MMPs are divided into collagenases, gelatinases, stromelysins, matrilysins, and membrane-type (MT) MMPs, as well as some other non-classified MMPs.[1]
Traffic Management: The Indispensable Vesicular Transport System
When I taught high school biology, a favorite part of the curriculum was cellular structures and functions. I set up an activity suggested by other experienced biology teachers that was based on the “Cell City,” a learning analogy where students would create an artwork of a city with the mitochondrion as a power plant and a vacuole as a lake. (Figure 1) I wish I saved their very creative projects, but I distinctly remember one group used the Chicago Transit Authority’s elevated train system map to represent the endoplasmic reticulum (ER), a very clever use of the analogy and a nod to city pride. It was also the first time these students really thought about vesicular transport, although they didn't fully understand its importance.
Transcriptional Regulation of Myogenic and Metal Homeostasis Genes
On January 12, 2021, we had the privilege of hosting Dr. Teresita Padilla-Benavides, an Assistant Professor of Molecular Biology and Biochemistry at Wesleyan University in Middletown, CT, to present our first webinar of the new year. Her webinar discussed her research on the differential mechanisms for transcriptional regulation of myogenic and metal homeostasis genes. If you missed the live session of the webinar, we’ve got you covered here with a link to a recording of the webinar, as well as a recap below: