Evidence Based

CYP1B1 Enzyme: Function & Ways to Increase / Decrease It

Written by Biljana Novkovic, PhD | Last updated:

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CYP1B1 is an important detox enzyme that helps combat oxidative stress. This enzyme is also important for eye development. Mutations in the CYP1B1 gene are associated with congenital glaucoma. On the other hand, lower activity of this enzyme may be protective against obesity and cancer, by regulating the levels of steroid hormones in our bodies. Learn more about this enzyme and factors that can increase or decrease its activity.

What is CYP1B1?

The enzyme CYP1B1 is one of the cytochrome P450 monooxygenases (CYPs). These are enzymes that eliminate most of the drugs and toxins from the human body [1].

Read more about CYPs here.

CYP1B1 Function

This enzyme metabolizes:

  • steroid hormones [2], including estrogens [3, 4]. CYP1B1 is also responsible for the final steps in the production of cortisol and aldosterone [5].
  • fatty acids and fat-soluble vitamins [2, 6].
  • melatonin [2].
  • retinol and dietary plant flavonoids [7].
  • polycyclic aromatic hydrocarbons (PAHs), biphenyls, N-heterocyclic amines, arylamines, aminoazo dyes, and other cancer-causing and toxic environmental chemicals [8, 2].
  • CYP1B1 metabolizes few, if any, clinical drugs [8].

CYP1B1 Location

This enzyme is found in the liver, but also in various other tissues including fat, skin, breast gland, prostate, heart, blood vessels, kidney, thymus/marrow and immune cells, breast, uterus, brain, and eyes [6, 2, 7, 8, 9].

CYP1B1 The Good

An important role of CYP1B1 is that it helps reduce oxidative stress [6, 10]. CYP1B1 deficiency results in increased oxidative stress in mice [11].

Also, this enzyme is important for eye development [9, 12]. Many mutations in CYP1B1 cause primary congenital glaucoma [12, 13].

This enzyme can protect from cancer. CYP1B1 deficient mice have more lung tumors [14].

Finally, CYP1B1 supposedly activates salvestrols, compounds found in vegetables, fruits, and herbs, that then help fight cancer. However, there are no scientific studies backing these claims.

CYP1B1 The Bad

This enzyme is produced by fat tissue, and it helps increase fat uptake [6].

In mice, CYP1B1 deficiency increases AMPK, reduces obesity, reduces blood pressure, and improves glucose tolerance [6, 15].

Furthermore, this enzyme is capable of activating a wide range of cancer-causing compounds [16, 10].

CYP1B1 activity was shown to promote the growth and metastasis of non-small lung cancer cells [17] and may promote the growth of renal cell carcinoma (kidney cancer) cells [18].

CYP1B1 Gene Polymorphism

More than 150 SNPs have been reported for this gene [13, 11].

Many of the mutations cause primary congenital glaucoma [12, 6].

  • RS10012

rs10012 alters androgen (testosterone) concentrations (1499 cases and 1373 controls) [19], with the C variant being more active [20].

This may explain the association of the C variant with increased disease aggressiveness in prostate cancer (1387 subjects) [21].

The C variant was also associated with an increased risk of endometrial cancer (200 subjects) [22].

On the other hand, the G variant was associated with urinary bladder cancer (492 subjects) [23].

  • RS1056827

This variant is also known as Ala119Ser.

rs1056827 T is the more active variant of the enzyme [20].

This variant (T) correlates with urinary bladder cancer (492 subjects) [23], higher risk of prostate cancer (meta-analysis, 34 studies, 17,796 cases, and 19,891 controls) [24] and breast cancer (same meta-analysis, 17,796 cases, and 19,891 controls) [24].

  • RS1056836

rs1056836 is also known as Leu432Val.

People with the G variant for rs1056836 have higher enzyme activity (about 3 fold) [25, 26].

G increases susceptibility to hepatocellular carcinoma (983 subjects) [27], multiple myeloma (1061 subjects) [28], lung cancer (meta-analysis, 22 studies, 2881 cases, and 3653 controls) [29], and endometrial cancer, but lowers the risk of ovarian cancer (meta-analysis, 115 studies, 54,124 cases, and 62,932 controls) [24] and prostate cancer (1387 subjects) [21].

Having two C variants (C/C) increases bloating, facial hair, palpitations, and involuntary urination in premenopausal women. Also, C/C increases the experience of nausea, bloated stomach, facial hair, and vaginal dryness in peri- and postmenopausal women. Carriers of C/C or C/G were approximately five times more likely to suffer from vaginal dryness than the G/G women (299 women) [30].

G was associated with shorter average telomere length in postmenopausal women taking hormonal therapy (259 subjects) [26]. Short telomere length is associated with premature aging and age-related disease.

  • RS1800440

RS1800440 is also known as Asn453Ser.

G was associated with a decreased risk of endometrial cancer (meta-analysis, 48 studies, 30,532 cases, and 39,193 controls) [24].

  • RS150799650

rs150799650 T was associated with urinary bladder cancer (492 subjects) [23].

Increasing or Decreasing CYP1B1

These increase CYP1B1:

These decrease CYP1B1:

  • St. John’s wort [34]
  • Apigenin [34]
  • Ginseng [35]
  • Lycopene, a red pigment found in tomatoes, carrots, and watermelon [36]
  • Chrysoeriol, present in rooibos tea and celery [37]
  • Naringenin, found in grapefruit juice [38]
  • Zyflamend, a polyherbal formulation produced from the extracts of ten common herbs (rosemary, turmeric, ginger, holy basil, green tea, hu zhang, Chinese goldthread, barberry, oregano, and Baikal skullcap) [39]
  • Quercetin [40]

About the Author

Biljana Novkovic

Biljana received her PhD from Hokkaido University.
Before joining SelfHacked, she was a research scientist with extensive field and laboratory experience. She spent 4 years reviewing the scientific literature on supplements, lab tests and other areas of health sciences. She is passionate about releasing the most accurate science & health information available on topics, and she's meticulous when writing and reviewing articles to make sure the science is sound. She believes that SelfHacked has the best science that is also layperson-friendly on the web.

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