PROMISING NEW FINDINGS FOR ROSEMARY

The leaves and sprigs of Rosemary (Rosmarinus officinalis), have been widely used in food preparation and preservation and also for many medicinal purposes, almost as far back as human history began. As a popular plant that is easy to use and often readily accessible, its reputation as a meat preserver and an alleged hair restorer, are fairly well known in herbal folklore.

As with other long-esteemed herbaceous plants, rosemary’s diverse medicinal capabilities and their relevance to the needs of a modern-day world are being increasingly validated by modern research.  Rosemary is now known to have some powerful pharmacological actions, including antioxidant, hepatoprotective, anti-cancer, antimicrobial and potential antidepressant activities(1).

Further possible medicinal uses for this well-known plant have now emerged, following results from recent research.

Preservative actions have long been assigned to rosemary, and scientific evidence supporting an antimicrobial application is very encouraging(2,3). An ethanolic rosemary extract was recently reported to have promising antibacterial activity against different pathogenic bacteria, with particularly good activity against Klebsiella pneumoniae(4). The essential oil of rosemary also exhibits powerful bactericidal (bacteria killing) and anti-biofilm activity against Staphylococcus aureusand Staphylococcus epidermidis(5), common causes of infections such as UTI’s and those from medical devices such as catheters.

Another study by veterinarian researchers recently, found that rosemary essential oil improved the motility of sperm collected from roosters, during its storage at 4 degrees C. These benefits were particularly seen when low concentrations of 8.7 and 87 ug/ml of rosemary essential oil were used. This suggests potential uses in animal fertilisation, and in human fertility clinics and procedures(6). With declining rates of sperm counts and motility, anything that gives sperm a greater chance of successfully fertilising an egg, can only be a good thing. As such it is conceivable that humans (or prehumans) may become exposed to this remarkable herb even before conception itself in the future!

Rosemary also has a reputation for helping prevent cancer, and application of rosemary or its phenolic acid constituents carnosol and ursolic acid were first shown to inhibit skin cancer formation in 1994(7).  Such actions have since been extended to other forms of cancer cells, including most recently the growth of human colon adenocarcinoma(8), and three other gastrointestinal cancer cell lines(9).

Benefits on heart health are also associated traditionally with regular ingestion of this herb, and recent studies on rodents have provided some support for this.  Pre-treatment with an aqueous rosemary extract protected mice against cardiotoxicity and hepatotoxicity(10). Supplementation of the diet of rats with 0.02% rosemary for three months improved diastolic function, and reduced the degree of hypertrophy after a heart attack (myocardial infarction). These effects were associated with improved energy metabolism and decreased oxidative stress(11). Rosmarinic acid has also shown a cardioprotective effect against myocardial infarction and arrhythmia in rats(12).

Collectively, these recent studies supportfurther investigations into the potential use of rosemary as adjuvant therapy with other cardiac drugs in those at risk of a heart attack, or to be taken immediately following such life-threatening cardiac events.

Finally, rosemary is also used in traditional medicine to alleviate rheumatic and abdominal pain. In a rat model of painful diabetic neuropathy, rosemary extract improved hyperglycemia, hyperalgesia and motor deficit(13). Triterpene constituents of an ethanolic extract also reduce abdominal pain in mice(14). These findings suggest rosemary may have analgesic and neuroprotective effects in painful diabetic neuropathy as well as abdominal pain in humans. Rosmarinic acid is likely to contribute to these effects, as other recent studies found it effective in a rat model of neuropathic pain(15-17). Analgesic properties have also previously been reported for rosemary essential oil (18).

Rosmarinic acid is a highly valued phenolic compound found not only in Rosemary, but also in many other well-known plants in the Lamiaceaeand Boraginaceaefamilies, such as Sage, Lemon balm, and Perilla (Perilla frutescens). Potentially beneficial pharmacological properties of this natural compound include anticancer, anti-angiogenic, anti-inflammatory, antioxidant, and antimicrobial activities(19,20). This has lead to increasing demands for it from the pharmaceutical industry. As a result, methods to chemically synthesise rosmarinic acid or produce it by biotechnological methods, are now being actively explored(19).

Beyond rosmarinic acid, however, the cumulative research into the diverse pharmacological actions of the reliable rosemary, show that other phenolic acids, triterpenoids, essential oil and other constituents, also seem to make powerful contributions to its many potential medicinal uses.

 

References:

  1. Andrade JM et al, Future Sci OA. 2018 Feb 1;4(4):FSO283.
  2. Ahn J et al, Food Microbiol. 2007 Feb;24(1):7-14
  3. Nieto Get al, Medicines (Basel).2018 Sep 4;5(3).
  4. Javed H 1stal, Pam J Pharm Sci 2018; 31(3):933-939.
  5. Jardak M et al, Lipids Health Dis.2017 Oct 2;16(1):190.
  6. TouaziL et al, Vel World 2018; 11(5):590-597.
  7. HuangMT et al, Cancer Res.1994 Feb 1;54(3):701-8.
  8. Jaksevicius A, et al, Nutrients. 2017 Sep 21;9(10).
  9. Karimi N, Gastroenterol Hepatol Bed Bench. 2017 Spring;10(2):102-107.
  10. Hamed H et al, Appl Physiol Nutr Metab.2018 Apr 9. doi: 10.1139/apnm-2017-0786. [Epub ahead of print]
  11. Murino Rafacho BP, PLoS One. 2017 May 11;12(5):e0177521
  12. Javidanpour Set al, 2017 Dec;51(11-12):911-923.
  13. Rasoulian B et al, J Physiol Sci 2018; May 12 (epub ahead of print).
  14. Martinez AL et al, J Ethnopharmacol 2012; 142(1):28-34.
  15. Rahbardar GM et al, Biomed Pharmacother. 2017 Feb;86:441-449
  16. Rahbardar MGet al 2018 Feb 1;40:59-67
  17. Di Cesare Mannelli L et al,Sci Rep. 2016 Oct 7;6:34832.
  18. Raskovic A, et al, Eur Rev Med Pharmacol Sci. 2015 Jan;19(1):165-72.
  19. Swamy MK et al, Appl Micriobil Biotechnol 2018.
  20. Shekarchi M et al, Pharmacognosy Mag 2012; 8(29):37-41.
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Herbs and Cancer

A diagnosis of cancer is a highly stressful experience and increasingly, a common reason for people to consult a medical herbalist. With ongoing environmental exposures to carcinogenic agents, genetic predispositions and aging populations, this is likely to continue in coming decades.

Pharmaceutical company expenditure on research into new cancer drugs far outweighs that spent on developing new antibiotics or antidepressants, and advances in diagnosis, surgery, chemotherapy, radiotherapy and other cancer treatments, continue to be made. These can be expensive however, and waiting lists unacceptably long, in an increasingly stressed healthcare system. Also, conventional medicine is not always effective in the treatment of cancer and in many patients, its adverse effects and a relatively poor risk versus benefit rationale, are reasons for exploring herbal and other natural treatments.

Consequently, there is a huge amount of material on the subject available online, in magazines and books, including websites offering cancer cures through expensive clinic programmes, or ‘ready to take’ products that are heavily marketed. Soon after informing friends, colleagues and family, newly diagnosed patients tend to be inundated with suggestions and recommendations to take a wide range of ‘herbal remedies’, ‘dietary supplements’, ‘superfoods’ and other ‘alternative treatments’, several promising a cure, and strongly advocating against conventional treatments.  Care should be taken with all of these.

It’s fairly well known that a large percentage of chemotherapeutic drugs for cancer and leukaemia treatment are molecules identified and isolated from plants or their synthetic equivalents or close derivatives. Research on herbs has led to the development of anti-cancer drugs such as vincristine, vinblastine, paclitaxel, docetaxel, etoposide, teniposide and more.

These are however, strong and individual chemicals found in or derived from plants, they are not the plants themselves. It is inappropriate to extrapolate from the anticancer effects of large doses of these drugs (often given by injection rather than orally), and to claim that a plant extract from which chemotherapy drugs have been developed will also exhibit significant anticancer properties. Also, successful traditional uses of most of these plants for the treatment (as opposed to prevention) of cancer in humans is in fact poorly established. Finally, the likelihood of something that kills cancer cells in vitro (in laboratory cultures) doing the same thing when taken orally by human patients, is actually pretty low, just as the diabetes drug insulin is poorly absorbed when taken orally, and needs to be administered by injection.

Of more relevance from a scientific evidence-based perspective, are herbs and natural products that show useful outcomes (efficacy) when used in studies involving rats and mice (rodents). We now know that the mouse and human genomes are approximately 85% identical, meaning that if something works in mice, it has a reasonable chance of also working in humans. A 2005 Canadian study that found daily oral ingestion of Echinacea purpurea root from the age of 6 weeks until death from natural causes (‘old age’) reduced the incidence of spontaneous tumours and prolonged the life expectancy of mice, is therefore highly relevant(1, 2). This type of study should be given more prominence than claims that oral administration of Madagascar periwinkle (Catharanthus roseus, the source of the anti-cancer drugs vincristine and vinblastine), can help fight cancer.

The best contribution that most herbs make is in fact related to their preventive effects against human cancers, just as a diet rich in vegetables and low in or excluding red meat is now well established to do the same. Well-known herbs and spices such as ginger, garlic, turmeric, rosemary, nasturtium and watercress, are just some for which compelling evidence now exists as to their prophylactic properties. Incorporating these and many others into the diet or taking as a tonic on a regular basis, is likely to help reduce the likelihood of developing many different types of cancer.

When it comes to management of patients with a cancer diagnosis, one of the most promising contributions that herbs can make, is as adjunctive treatments to be taken alongside the anti-cancer drugs and other conventional interventions that modern medicine now has available. Evidence from a large number of animal studies and a growing number of human clinical trials, now strongly supports this approach, key outcomes being to help increase the chances of achieving remission, and/or reduce the likelihood of treatment-related adverse effects such as infertility and fatigue. Sadly, however, most of my cancer patients don’t come to see me until either after they have undergone chemotherapy, or where it is no longer an option, and a small number firmly opt against conventional treatment. This is perfectly their right and completely understandable, but may not have been their decision if they had been informed of the valuable contribution an individualised concurrent herbal treatment regimen can sometimes make.

It is in fact a reflection of the widespread lack of acknowledgement and appropriate regulation of highly trained medical herbalists, that most people’s view of virtually all herbs and herbal products, is that they are only things to be sourced from ‘over the counter’ (OTC) or internet outlets. This is a far cry from their view of drugs, where when suffering from most debilitating or serious conditions, the prescribing expertise of a medical practitioner or specialist such as an oncologist, is sought prior to embarking upon drug treatments.

While proactive selfcare should be actively encouraged as the best preventive approach to cancer and other illnesses. However, once cancer is diagnosed, while herbs are rarely a magic cure, seeking the best professional advice rather than relying on google apps or recommendations from those not trained in herbal medicine, is highly recommendable.

 

Refs:

 

  1. Brousseau M, Miller Enhancement of natural killer cells and increased survival of aging mice fed daily Echinacea root extract from youth. Biogerontology. 2005;6(3):157-63.

 

  1. Miller Echinacea: a miracle herb against aging and cancer? Evidence in vivo in mice.

Evid Based Complement Alternat Med. 2005 Sep;2(3):309-14.