Endothelial cells, COVID-19, and Vitamin C

Endothelial cells line the blood vessels and like other cells do have ACE2 receptors and may be able to be infected by the SARS-CoV-2 virus. In more severe cases of symptomatic infection the disease progresses beyond respiratory symptoms to include vascular symptoms and increased risk of blood clots and strokes. Some patients had vascular symptoms without having had severe respiratory symptoms. The illness is unlike other respiratory viral infections and may involve infection of the vascular endothelial cells as well.

The vascular symptoms can also be caused by the body’s natural response to infection to move iron from hemoglobin in red blood cells into storage in other cells where it could be less available to a pathogenic microbe. Anemia of chronic infection or chronic inflammation can result from the shift of iron. Too little hemoglobin means too little oxygen carrying capacity in the blood.

For whatever cause, viral entry of vascular endothelial cells or anemia of chronic infection, the good news is that vitamin C and other nutrients help strengthen vascular walls and reduce inflammatory cytokine production, and reduce risk of blood clots,

Vitamin C protects blood vessel lining. The endothelial cells lining blood vessels form a tight barrier, which is weakened (permeabilized) by inflammation. Vitamin C tightens the endothelial barrier and maintains its integrity during inflammation

Vitamin C Protects Blood Vessel Lining, VUMC Reporter, https://news.vumc.org/2015/09/04/vitamin-c-blood-vessel-lining/

Bioflavonoids, and other polyphenols and antioxidants would all still be helpful treatments for reducing oxidative stress, strengthening blood vessels, preventing coagulation, and reducing cytokine storm. See previous post for more information on bioflavonoids which also help reduce blood clotting risk and may act as decongestants if enough is eaten – Bitter taste receptors in the lungs & Hesperidin’s decongestant properties.

Other phytonutrients that may help against SARS-CoV-2 infection are listed in this post: Phytonutrients that may help against SARS-CoV-2.

Foods that may help if intestinal inflammation is also a problem (GI discomfort, diarrhea, a few points about nausea relief) ACE2, Diarrhea, & COVID19 – it gets complicated.

Disclaimer: This information is provided for educational purposes within the guidelines of Fair Use. It is not intended to provide individual guidance. Please seek a health care provider for individualized health care guidance.

CoV-19 nutrition research announcement by the Dutch firm Nutricia, link

Global research to define nutrition guidelines for recovering COVID-19 patients, 29-May-2020 By Nikki Hancocks, “Dutch nutrition research and innovation firm Nutricia has announced it will support a series of research projects taking place around to world over the following weeks to help define nutrition guidelines to help speed up the recovery of COVID-19 patients.” https://www.nutraingredients.com/Article/2020/05/29/Global-research-to-define-nutrition-guidelines-for-recovering-COVID-19-patients#

Disclaimer: This information is provided for educational purposes within the guidelines of Fair Use. It is not intended to provide individual guidance. Please seek a health care provider for individualized health care guidance.

Pomegranate peel catechins – inhibition of NET formation

We could show that the flavonoids (−)-epicatechin, (+)-catechin hydrate, and rutin trihydrate as well as vitamin C and the pharmacological substances N-acetyl-L-cysteine and 5-aminosalicylic acid inhibited PMA induced ROS production and NET formation.” (Kirchner, et al, 2013)

Why care about NET formation? because it may be associated with worse risk of coagulation and blood clots forming in severe COVID-19 illness. ((Thierry and Roch, 2020), (Kiefer, 2020) Interleuken-6 (IL-6) can increase NET formation by neutraphil white blood cells attempting to ensnare pathogens and IL-6 levels tend to be elevated in more severe COVID-19 illness.

NET-neutraphil extracellular traps: “Thrombosis [coagulation/blood clotting], sepsis, and thick mucous secretions share neutrophil extracellular traps as a common causal agent. In addition to phagocytosis and degranulation, neutrophils can kill pathogens by extruding neutrophil extracellular traps (NETs), a process termed NETosis.” (Yanuck, et al)

Rutin is found in citrus peel and other plants. Epicatechin and catechin hydrate are in pomegranate peel or juice possibly (more in the peel). N-acetyl-L-cysteine is available as a supplement also known as NAC, and 5-aminosalicylic acid is a medication. Acetylsalicylic acid is aspirin and it also inhibits NET formation. (search results) Salicylic acid may be in some spices/plant foods. Many spices used in Indian cooking are good sources of salicylic acid. (post: Carrots, Spices, and baby aspirin help prevent cancer)

Disclaimer: Opinions are my own and the information is provided for educational purposes within the guidelines of fair use. While I am a Registered Dietitian this information is not intended to provide individual health guidance. Please see a health professional for individual health care purposes.

Reference List

  1. (Kirchner, et al, 2013) Kirchner T, Hermann E, Möller S, et al. Flavonoids and 5-aminosalicylic acid inhibit the formation of neutrophil extracellular traps. Mediators Inflamm. 2013;2013:710239. doi:10.1155/2013/710239 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3871909/
  2. (Yanuck, et al) Yanuck SF, Pizzorno J, Messier H, Fitzgerald KN, Evidence Supporting a Phased Immuno-physiological Approach to COVID-19 From Prevention Through Recovery. athmjournal.com/ https://athmjournal.com/covid19/research/evidence-supporting-a-phased-immuno-physiological-approach-to-covid-19-from-prevention-through-recovery/ *”interventions for one phase may not be appropriate for a different phase. The 4 phases addressed are: Prevention, Infection, Inflammation & Recovery.
  3. (Thierry and Roch, 2020) Thierry AR, Roch B. SARS-CoV2 may evade innate immune response, causing uncontrolled neutrophil extracellular traps formation and multi-organ failure. Clin Sci (Lond). 2020 Jun 26;134(12):1295-1300. doi: 10.1042/CS20200531. PMID: 32543703. https://pubmed.ncbi.nlm.nih.gov/32543703/
  4. (Kiefer, 2020) Julie Kiefer, Clues to COVID-19 Complications Come from NET-Like Inflammatory Response. Jun 29, 2020, healthcare.utah.edu, https://healthcare.utah.edu/publicaffairs/news/2020/06/nets-covid.php

Pomegranate, neuroinflammation, antimicrobial, metal chelator.

Pomegranate and its various products all have been found to have beneficial phytonutrients. The antioxidant power of the peel is strong enough to protect metal from rusting. The juice also includes polyphenol antioxidants that can enter the blood brain barrier (1, 4) and help detoxify oxidative stress chemicals within the brain (1 4), – anti-corrosive for the brain.

A metabolite (UA) of the pomegranate polyphenols was measured in brain tissue and blood plasma during an animal study. (4) “The concentration of UA in the brain was 1.68 ± 0.25 ng/g tissue and in plasma 18.75 ± 3.21 ng/mL. ” (4) It also seemed to increase activity of an anti-inflammatory enzyme (“GPx activity“) which would increase our own antioxidant production and helped reduce levels of the amyloid-β protein that is thought to be involved in Alzheimer’s dementia . (4)

  • It seems that PJ [pomegranate juice] caused down-regulation of α-synuclein protein expression since in rats treated alone with the juice, the levels of α-synuclein oligomers was decreased while the ratio of this fraction to monomeric was higher than in Control. This effect is likely to be involved in the improvement of neuronal cell survival, which was also reported for other natural preparations [42,62]. ” (4)

Pomegranate extract helped reduce/improve the balance of levels of the amyloid-β proteins involved in Alzheimer’s dementia in an animal model of the disease. (2) “The mice (age 24-30 mo) received either PE [pomegranate extract] (at 100 & 200 mg/kg) or a control solution daily for three weeks” (2)

What is standardized pomegranate extract? And how might you calculate a human dose?

It is hard to know and dose might vary with the type of pomegranate extract. Whether the seed, juice or peel, or the whole fruit is used to make the pomegranate extract might vary – read each article for details. Pomegranate Peel Extract (PPE) is used regularly in research regarding the medical uses.

  • Doses of 100 or 200 mg/kg of “a standardized pomegranate extract (PE)” was used in a study of an aged Alzheimer’s disease animal model. Ratios of the amyloid-beta proteins thought to be involved in Alzheimer’s disease were improved. (2) “Our findings support a specific anti-amyloidogenic mechanism of a pomegranate extract in this aged AD animal model. ” (2)
  • Pomegranate seeds (PGSE) were used to make the extract for an animal study of ischemic stroke damage to the brain. Doses of 100 or 200 mg/kg were found protective against oxidative damage. (1) An upper tolerance dose was trialed at 800 mg/kg but it did not cause toxic effects.
    • No toxicity was observed even with high-dose PGSE consumption (800 mg/kg, for 14 days). ” (1)

Without knowing how the extract was made, roughly an adult size amount (for a person weighing 70 kilograms/154 pounds) might be 7-14 grams per day (approximately 2-4 teaspoons).

I found 1-2 tablespoons (3-6 teaspoons) of my whole peel extract to be a beneficial amount for my symptoms. It can have diuretic side effects, use early in the day and have some extra nondiuretic fluids. Using only the inner white part of the peel can reduce the diuretic effects without losing other health benefits – the ratio of phytonutrients is slightly different for the inner and outer part of the peel, with both containing some of the hyrolyzable tannins that have healing, and diuretic effects. For directions/recipe and more information see: G13. Pomegranate Benefits and Preparation.

Pomegranate juice also was found neuroprotective in an Alzheimer’s animal model study. “Commercial 6-fold concentrated pomegranate juice (PJ) […] The total polyphenols content expressed as g of ellagic acid (EA) equivalents per L of juice was 18.90 ± 0.96 g/L. (4)

For humans eight ounces of pomegranate juice daily for four weeks was found beneficial for memory and changes in blood tests suggested it was being absorbed in an amount sufficient to help against inflammation.

In older subjects with age-associated memory complaints, who drank 8 ounces of pomegranate juice for four weeks, a significant improvement in verbal and visual memory as well as an increase in plasma Trolox-equivalent antioxidant capacity was observed. Noteworthily, individuals drinking pomegranate juice represented an increased level of a metabolite of pomegranate ellagitannins—urolithin A glucuronide—in plasma [15]. It is believed that pomegranate’s neuroprotective effects are mediated by urolithins—the colonic microbiota ellagitannins (ETs)-derived metabolites [8].” (4)

From my own use I have found about four ounces per day beneficial for mood and four ounces twice a day was helpful on a bad day. The fresh seeds, 1/3-1/2 cup also helped my anxiety symptoms in a similar way. Dried pomegranate seeds, anardana, are available in markets with foods from India, about 2-3 tablespoons might be an equivalent serving.

Pomegranate extracts may also have healing benefits when used topically, for wound care in this study:

  • Whole fruit extract was used topically, diluted to 7.5% was mentioned in an animal based study on wound healing. “…whole fruit extract of pomegranate (P. granatum Linn.) standardized with 40% ellagic acid produced by Xi’an Bio-Technology Co., Ltd.,…” (3)

Regarding CoV19 & pomegranate peel

In the case of SARS-CoV-2/COVID-19 there may be a problem with the virus suppressing the normal immune response of interleuken I and III (ref) Inflammatory interleuken 1 and 6, IL-1 and IL-6, can become elevated in patients with severe illness. Pomegranate peel or whole fruit extract has been found to have significant anti-inflammatory and immune-modulating effects. In different studies it has been shown to have benefits by inhibiting levels of IL-1, (7) , and IL-6. (5)

  • PGPE consumption […] prevent the instigation of a low-grade inflammatory status compared to OVX Control animals, through the down-regulated expression of CCL2 (0.33-fold; p < 0.05) & IL1-R1 (0.64-fold; p < 0.001) and the up-regulated expression of IL1-Rn (1.89-fold; p < 0.001)” (7)
    • IL1-Rn= “IL-1 receptor antagonist allows unopposed IL-1 activation” (6)
  • In another study, we demonstrated that PFE significantly inhibited the excessive production of IL-6 and IL-8 via suppression of the JNK-, extracellular signal-regulated kinases (ERK)- MAPKs and NF-κB-signaling events. (19)  ” (5)

*preliminary version.

Disclaimer: This information is provided for educational purposes within the guidelines of Fair Use. It is not intended to provide individual guidance. Please seek a health care provider for individualized health care guidance.

Reference List

  1. Sarkaki A, Rezaiei M, Gharib Naseri M, Rafieirad M. Improving active and passive avoidance memories deficits due to permanent cerebral ischemia by pomegranate seed extract in female rats. Malays J Med Sci. 2013;20(2):25–34. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3743996/
  2. Ahmed AH, Subaiea GM, Eid A, et al., Pomegranate extract modulates processing of amyloid-β precursor protein in an aged Alzheimer’s disease animal model. Curr Alzheimer Res. 2014;11(9):834-43. https://ncbi.nlm.nih.gov/pubmed/25274111
  3. Yuniarti WM, Primarizky H, Lukiswanto BS. The activity of pomegranate extract standardized 40% ellagic acid during the healing process of incision wounds in albino rats (Rattus norvegicus). Vet World. 2018;11(3):321–326. doi:10.14202/vetworld.2018.321-326 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5891847/
  4. Kujawska M, Jourdes M, Kurpik M, et al. Neuroprotective Effects of Pomegranate Juice against Parkinson’s Disease and Presence of Ellagitannins-Derived Metabolite-Urolithin A-In the Brain. Int J Mol Sci. 2019;21(1):202. Published 2019 Dec 27. doi:10.3390/ijms21010202 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6981883/Commercial 6-fold concentrated pomegranate juice (PJ) was obtained from Alter Medica (Żywiec, Poland). The product was manufactured in accordance with the principle of HACCP (hazard analysis and critical control point) and fruit ingredients are fully compliant with the Code of Practice of the European Fruit juice Association (AIJN). Since pomegranate’s ellagitannins and their hydrolysis product—ellagic acid—have been demonstrated to be precursors of potentially neuroprotective urolithins, including urolithin A [8], which we detected in this study, we identified these phenolics in the tested juice. The ellagitannin composition of PJ was as follows: Galloyl-hexoside, ellagic acid-hexoside, 3-bis-HHDP-hexoside (pedunculagin), 4-galloyl-bis-HHDP-hexoside (casuarinin), and ellagic acid (Figure S1). The total polyphenols content expressed as g of ellagic acid (EA) equivalents per L of juice was 18.90 ± 0.96 g/L. ” *so full strength juice might have a sixth or approximately 3 grams/L of ellagic acid.
  5. Rasheed Z. Intake of Pomegranate Prevents the Onset of Osteoarthritis: Molecular Evidences. Int J Health Sci (Qassim). 2016;10(2):V‐VIII. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4825888/In another study, we demonstrated that PFE significantly inhibited the excessive production of IL-6 and IL-8 via suppression of the JNK-, extracellular signal-regulated kinases (ERK)- MAPKs and NF-κB-signaling events. (19) “
  6. IL1RN interleukin 1 receptor antagonist [ Homo sapiens (human) ], Gene ID: 3557, updated on 17-Apr-2020 https://ncbi.nlm.nih.gov/gene/3557
  7. Mélanie Spilmont, Laurent Léotoing, Marie-Jeanne Davicco, et al., Pomegranate Peel Extract Prevents Bone Loss in a Preclinical Model of Osteoporosis and Stimulates Osteoblastic Differentiation in Vitro, Nutrients 2015, 7(11), 9265-9284; https://doi.org/10.3390/nu7115465 https://www.mdpi.com/2072-6643/7/11/5465/htm
  8. **helped “encephalitis lethargica symptoms during ME(ME/CFS) ” anecdotal.

Today, it is well-known that the TRPA1, TRPC5, TRPM2, TRPM7, TRPV1, TRPV3, and TRPV4 cation channels are activated by ROS and reactive nitrogen species (RNS) [2932].” (Nazıroğlu 2015)