Updated: Oct 7
One of the enzymes i referenced in a prior blog article, GPX4, has been getting lots of attention lately in published work related to long haul. GPX4 is the only glutathione peroxidase enzyme located inside the mitochondria to detox lipid peroxidation. Seems pretty interesting, huh.
It is also one of the common trouble makers i see mutated in long haul cases. Hmmm, and lots of research all of a sudden.
Well, lets get right to it, if GPX4 is compromised, how can we help stimulate it ?
If you dig into the reference articles, you can see the links between GPX4 and Ferroptosis. A simple google search of ferroptosis and long haul lets you see how much research links ferroptosis to long haul. Simply put ferroptosis is unmitigated cell death. Hmm. I will illuminate other links to ferroptosis in later blogs, specifically BH4 (and the link to the rate limiting enzyme GCH1 in the production of BH4), excess iron (which induces lipid peroxidation), and coq10.
Selenium is a Cofactor for GPX4
"Emerging evidence suggests that selenium plays an essential role in sperm maturation. However, the specific signaling pathway by which selenium exerts effect has not been elucidated. To evaluate the effect of selenium on GPX4-mediated lipid peroxidation and apoptosis in germ cells, selenium deficiency was modeled by culturing GC2-spd cells in serum-free medium. Treatment with 0.5-μM sodium selenite (NaSe) or 5.0-μM selenomethionine (SeMet) significantly improved the proliferation rate and GPX4 protein expression after selenium deficiency. Moreover, NaSe and SeMet decreased the MDA content and lipid peroxidation. When adenovirus was used to knockdown the expression of the GPX4 gene (shRNA-GPX4), the early apoptosis rate of the shRNA-GPX4 cells was significantly higher than that of the EGFP cells. Increased expression of Caspase3 and Bax, as well as MDA content were observed in the shRNA-GPX4 cells compared with EGFP cells. In further, overexpression of the GPX4 gene (ORF-GPX4) cells exhibited increased cell proliferation and decreased MDA content. However, there was no significant difference in 12/15-lox expression both in ORF-GPX4 cells and shRNA-GPX4 cells. Conclusively, GPX4 was involved in the regulation of lipid peroxidation and apoptosis in GC2-spd cells. Selenium played a role in promoting cell proliferation by mediating GPX4. The regulation of GPX4 may occur independently of 12/15-Lox. These findings confirmed the effect of selenium on spermatogenesis and offered a potential target for treating abnormal semen quality in men."[1, 2, 3]
Also interesting that Ron Davis at Stanford found compromised sperm in his male CFS patients:). And of course, those who have worked with me know, that ALOX12 and ALOX15 are on the short list of trouble makers for lipid peroxidation as well:).
Tannic Acid Stimulates GPX4
"Ferroptosis, an iron-dependent cell death, plays a crucial role in the pathology of Alzheimer's disease (AD). Several characteristics of AD, including excessive iron accumulation, elevated lipid peroxide and reactive oxygen species (ROS) levels, and decreased glutathione peroxidase 4 (GPX4) levels, align with the features of ferroptosis. While traditional methods of inhibiting ferroptosis have centered on chelating Fe and trapping radicals, therapeutic strategies that modulate the GPX4 axis to mitigate ferroptosis in AD are yet to be explored. This report introduces naturally occurring polyphenols (PPs) as dual-acting therapeutic agents to synergistically alleviate ferroptosis and AD. The mechanisms of action encompass modulation of amyloid and tau cascade, reduction of oxidative stress, mitochondrial rescue, and inhibition of ferroptosis. For the first time, we show that a single multifunctional molecule, tannic acid (TA) binds at the activator site of GPX4, augmenting both its activity and cellular levels, providing a conceptually innovative and integrated approach for treating AD via the GPX4–ferroptosis axis. The ability of TA to enhance GPX4 levels under conditions of AD pathology opens up newer promising therapeutic avenues for combating the crosstalk between ferroptosis and AD.". Related here is the ability to reduce Fe induced ferroptosis, and here EGCG is cited. Tannic Acid binds to the binding site on GPX4 that activates it and EGCG instead inhibits the binding of RSL3 to GPX4. RSL3 naturally binds to the site that inhibits GPX4. The combination of EGCG and Tannic Acid appears like a synergistic one:).
"However, the most common occurrence of Tannic Acid is in the twigs of certain trees, specifically Chestnut and Oak trees" 
Tannin-touting herbs include licorice, mint, rosemary, coriander (cilantro), and sage. Many spices also contain tannins and other phenolic compounds; two common ones are cinnamon and cloves. Others include ginger, black cumin seeds, and piripiri.  Black tea is the tea highest in tannins. Coincidentally, tannins bind metals, like iron, but also copper, mercury, etc. :).
A Chinese Herbal Mix Stimulates GPX4 Too! Shaoyao Decoction (SYD)
"SYD alleviated chemically induced colitis by activation of GPX4, inhibition of ferroptosis in epithelial cells and further restoration of barrier function. Wogonoside, wogonin, palmatine, paeoniflorin and liquiritin were identified as the key therapeutic material basis of SYD-exerted anti-colitis effects. The findings provide a scientific basis for the therapeutic effect of SYD on colitis."
Even Better - What is this Herbal Mix SYD - Shaoyao Decoction?
"SYD was made from nine herbs: Paeonia lactiflora Pall., Angelica sinensis (Oliv.) Diels., Coptis chinensis Franch., Areca catechu L., Aucklandia lappa Decne., Rheum palmatum L., Scutellaria baicalensis Georgi., Cinnamomum cassia Presl., and Glycyrrhiza uralensis Fisch.".
Hmm. Chinese Peony, Angelica, Chinese Skullcap, Cinnamon, Astragalus, Epimedium, Houttuynia, Motherwort, Andrographis. Hmm.
Vitamin E & GPX4 Combined:). And Guess What Helps ALOX12:)
"Ferroptosis, a newly defined mode of regulated cell death caused by unbalanced lipid redox metabolism, is implicated in various tissue injuries and tumorigenesis. However, the role of ferroptosis in stem cells has not yet been investigated. Glutathione peroxidase 4 (GPX4) is a critical suppressor of lipid peroxidation and ferroptosis. Here, we study the function of GPX4 and ferroptosis in hematopoietic stem and progenitor cells (HSPCs) in mice with Gpx4 deficiency in the hematopoietic system. We find that Gpx4 deletion solely in the hematopoietic system has no significant effect on the number and function of HSPCs in mice. Notably, hematopoietic stem cells (HSCs) and hematopoietic progenitor cells lacking Gpx4 accumulated lipid peroxidation and underwent ferroptosis in vitro. α-Tocopherol, the main component of vitamin E, was shown to rescue the Gpx4-deficient HSPCs from ferroptosis in vitro. When Gpx4 knockout mice were fed a vitamin E-depleted diet, a reduced number of HSPCs and impaired function of HSCs were found. Furthermore, increased levels of lipid peroxidation and cell death indicated that HSPCs undergo ferroptosis. Collectively, we demonstrate that GPX4 and vitamin E cooperatively maintain lipid redox balance and prevent ferroptosis in HSPCs." For those of you who have worked with me, you know the special form of Vitamin E i use for this.
It Gets Even Better - Another Study On What Herbs Upregulate GPX4
"Compared with the control group, mRNA expressions of glutathione peroxidase 1 (GPX1), peroxidase 4 (GPX4), catalase (CAT), and nuclear factor E2-related factor 2 (Nrf2) in the magnum, liver, and uterus were dramatically rose in the 0.4% PCHM supplementation group (P < 0.05)".
What the heck is PCHM? Epimedium (Barrenwort, Horny Goat Weed), Astragalus, Angelica, Leonurus (Motherwort), and Houttuynia.
EGCG Blocks RSL3 From Inhibiting GPX4
"Despite their significance, reports of small molecule activators of GPX4 are rare, while inhibitors of GPX4 such as RAS-selective lethal 3 (RSL3) and ML-162, that induce ferroptosis by inhibiting GPX4, are well documented. RSL3 binds to the inhibitor site of GPX4 and suppresses its activity while activating nuclear factor kappa B (NF-κB), leading to ferroptosis and cell death...........
The effect of TA (Tannic Acid) on GPX4 activity was assessed using a GPX4 inhibitor screening assay kit. In this assay, the consumption of NADPH by GPX4 was used to monitor enzymatic activity. A steady decrease in absorbance over time provided a reference kinetic curve for GPX4 activity. Incubation of GPX4 with RSL3 (20 μM) for 60 min inhibited GPX4 activity by 22%. However, at a concentration of 20 μM, both TA and EGCG were able to reverse the RSL3-induced inhibition by 12.3% and 9.5%, respectively. TA increases GPX4 activity by binding to its activation site. In contrast, EGCG does not bind to the GPX4 activation site but instead inhibits the binding of RSL3 to GPX4."
In sum, one potential strategy to support GPX4 would be to find some cross synergies across:
- Selenium as the cofactor
- Natural chelators of iron: Circumin, Uva Ursi, Cloves, skullcap
- Tannins to bind to the activator site (black tea, licorice, mint, rosemary, coriander (cilantro), and sage, cinnamon, cloves, ginger, black cumin seeds, and piripiri).
- Other known activators of GPX4 first study :Epimedium (Barrenwort, Horny Goat Weed), Astragalus, Angelica, Leonurus (Motherwort), and Houttuynia.
Activators of gpx4 from 2nd study, Chinese Peony, Angelica, Chinese Skullcap, Cinnamon, Astragalus, Epimedium, Houttuynia, Motherwort, Andrographis
- Block RSL3 with EGCG
a. Selenium as a cofactor,
b. EGCG to prevent inhibition
c. Activators that have tannins and studies that support activation:
Black Tea, Cloves, Cinnamon, Skullcap, Angelica, Astragalus, Motherwort, and Houttuynia
d. Vitamin E, and no, i dont suggest d alpha tocopherol:)
The above is not intended to be medical or healthcare advice. See your MD or Primary Care Physician before you embark on any supplement or dietary regimen.
The effects of selenium on GPX4-mediated lipid peroxidation and apoptosis in germ cells. Peiyi Liu, Jiahui Zhu, Guanxiang Yuan, et. al. Journal of Applied Toxicology. First published: 30 December 2021. https://doi.org/10.1002/jat.4273
Se improves GPX4 expression and SOD activity to alleviate heat-stress-induced ferroptosis-like death in goat mammary epithelial cells. Lu Liu, Manjiang Wang, et. al. , Animal Cells and Systems, 25:5, 283-295, DOI: 10.1080/19768354.2021.1988704. To link to this article: https://doi.org/10.1080/19768354.2021.1988704. Published online: 17 Oct 2021.
First line defence antioxidants-superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX): Their fundamental role in the entire antioxidant defence grid. O.M. Ighodaro a,b,⇑, O.A. Akinloye b, et. al. Department of Biochemistry, Faculty of Sciences, Lead City University, Ibadan, Nigeria. Available online 13 November 2017. Alexandria Journal Of Medicine.
A natural polyphenol activates and enhances GPX4 to mitigate amyloid-β induced ferroptosis in Alzheimer's disease. Prayasee Baruah, ‡a Hariharan Moorthy, et. al. Journal Of Chemical Science, Issue 35, 2023.
Therapeutic material basis and underling mechanisms of Shaoyao Decoction-exerted alleviation effects of colitis based on GPX4-regulated ferroptosis in epithelial cells. Juan Li, Xiangge Tian, et. al. Chinese Medicine volume 17, Article number: 96 (2022).
GPX4 and vitamin E cooperatively protect hematopoietic stem and progenitor cells from lipid peroxidation and ferroptosis. Qian Hu, Yifan Zhang, et. al. Cell Death & Disease volume 12, Article number: 706 (2021)
Effects of dietary pretreated Chinese herbal medicine supplementation on production performance, egg quality, uterine histopathological changes, and antioxidant capacity in late-phase laying hens. Ao-Chuan Yu, 1 , † Min-An Wang,Front Physiol. 2023; 14: 1110301. Published online 2023 Jan 20. doi: 10.3389/fphys.2023.1110301. PMCID: PMC9895833 PMID: 36744028
PlantChemCast - The Use of Plant Compounds From Tea To Medicine. Scitable By NatureEducation. July 18, 2013 | By: Mathew Pregasen