Cancer is the outcome of lawless cell division linked with cell cycle disorganisation, causing unchecked cell proliferation[1]. In addition, it also includes the dysregulation of apoptosis, inflammatory responses, immune evasion, and ultimately, metastatic spread[1].
The standard treatment regimens for cancer patients involve cancer surgery, chemotherapy, and radiotherapy. Although some of these treatments serve the first-in-line options for cancer treatment, the absence of selectivity towards the development of drug toxicity and neoplastic cells has made these therapeutic effects subside slowly, making them ineffective over the years[1]. Additionally, multidrug resistance tumours pose a serious threat and have been responsible for various cancer-related deaths[1]. A modern approach to point multiple cell regulating pathways is necessary to provide highly efficient and targeted cancer therapy[1]. For instance, combination therapy targeting several ways present significantly lower toxicity towards normal cells than mono-therapy[1]. Currently, the development of anti-cancer drugs possessing the capability to defeat common mechanisms of chemoresistance with the slightest toxicity effects would be considered a breakthrough in cancer research[1].
Approximately 70–95% of the world population remains to use traditional medicinal herbs, plants, and fruits that contain essential bioactive compounds with therapeutic effects to maintain health and stop or treat physical and mental illnesses[1].
Magnolia officinalis is an oriental flowering herb utilised in traditional Chinese medicine to stop anxiety, stress, depression, nervousness, and sleep-related problems[2]. Its bark contains active ingredients, i.e. polyphenols, namely magnolol and honokiol[2]. In vitro and in vivo studies proposed that these compounds have antimicrobial, anti-inflammatory, antidiabetic antidepressant, anxiolytic, and neuroprotective effects[2]. Recent studies have demonstrated anti-inflammatory, anti-angiogenic, anti-oxidative and anti-cancer properties of honokiol in-vitro and in preclinical models[3]. Honokiol showed antitumor and anti-angiogenic effects in leukaemia, lung cancer, bladder cancer, prostate cancer, melanoma, breast cancer, glioblastoma, neuroblastoma, and oral cancer[2], and magnolol exhibited activity against various cancers, including bladder cancer, prostate cancer, colorectal cancer, breast cancer, and lung cancer[2].
USES
(A) It may protect against the effects of oxidative stress and inflammation- Polyphenols, such as those obtained from magnolia bark, have been recommended as a potential therapy to fight the side effects of oxidative stress and inflammation[4].
Research on honokiol has shown that it can lessen the inflammation in the brain and spinal cord specifically, partly due to its capacity to cross the blood-brain barrier[4]. This research suggests that it has potential as a therapeutic agent for neurodegenerative diseases like Alzheimer’s [4].
Further, oxidative stress is popularly believed to contribute to diabetes and related complications.[4]. A 2016 review put forward that extracts of magnolia bark were found to improve high blood sugar levels and diabetic complications in animals[5].
But, additional research on humans is needed to be conducted to prove the same.
(B) It may help in cancer prevention- In a 2019 review, it is found that honokiol has the potential to stop tumour growth in the brain, breast, colon, liver, and skin, among other organs[6].
Moreover, honokiol may not only have anti-cancer properties but also aid in improving the effectiveness of other anti-cancer and radiation drug therapies[4].
But more rigorous human studies are still needed.
Related to honokiol, studies in animals have shown that other polyphenols, i.e. magnolol, may help to control and repress tumour growth in multiple organs[4]. Also, a test-tube study observed that magnolol inhibited the growth of lung cancer cells[4].
Yet, again, clinical studies on humans need to be conducted[4].
(C) It may relieve stress and anxiety- Magnolia bark extract has protective effects against many neurological conditions such as brain disorders like Alzheimer’s disease and other conditions like stress, anxiety, mood disorders, and depression[4].
(D) It may improve sleep- Honokiol and Magnolol have been found to help induce and improve sleep by affecting the activity of GABA(A) receptors which are closely associated with sleep[4].
Hence, magnolia bark could be used to remedy insomnia or promote better sleep overall[4].
(E) It may improve the symptoms of menopause- Some of the advantages of magnolia bark, such as improved sleep and mood, could be particularly beneficial for women during menopause only when given in concomitant with other compounds [4]. So we can’t say the lessening of menopausal symptoms were wholly due to magnolia bark[4]. Yet, it is considered to be a safe therapy that helps to treat menopause symptoms[4].
MECHANISM OF ACTION
Several anti-cancer mechanisms have been recognised with magnolol. In human bladder cancer cells, magnolol induced p27KIP1-mediated G2/M-phase cell cycle arrest to begin the extracellular signal-regulated kinase pathway[7] and decreases the binding of transcription factor NF-kappaB to DNA to stop MMP9 expression[2]. It also does dose-dependent growth inhibition along with apoptosis of cancerous bladder cells[7].
In prostate cancer cells, magnolol influenced the expression of insulin-like growth factor-1 (IGF-1) and linked binding proteins, hindered the EGFR/PI3K/Akt signalling pathway, and downregulated MMP2 and MMP9 protein and mRNA levels[2]. The antitumor activity also happens via MMP9 inhibition through the NF-kappaB pathway in breast cancer cells and AMPK activation in colorectal cancer cells[2].
Antitumor and anti-angiogenic characteristics of honokiol are ascribed to nuclear factor kappa beta (NF-kB) inhibition and the resulting scavenging of reactive oxygen species[2]. In human endothelial cells, honokiol restrains vascular endothelial growth factor receptor 2 (VEGFR2) phosphorylation[2]. It also prevented VEGF-induced Rac to stop the migration of malignant endothelial cells, obstructed signalling pathways in tumour cells with defective p53, and suppressed NF-kB overactivity[2]. In acute myeloid leukaemia cells, honokiol repressed STAT3 signalling through enhanced protein tyrosine phosphatase SHP1 expression[2]. It induced autophagy and activated a p53/cyclin D1/CDK6/CDK4/E2F1-dependent pathway to induce apoptosis and cell cycle arrest in glioma cells[2]. And in prostate cancer cells, honokiol suppressed c-Myc protein expression[2].
SIDE EFFECTS
A 2018 review of the safety and toxicity of the honokiol and magnolol compounds in magnolia bark ascertained that the substances are considered safe for human consumption[4].
Some studies have advised concentrated magnolia bark extracts for up to 1 year without any adverse effects[4].
Further, studies in both test tubes and living organisms have shown that magnolia bark extract has no mutagenic or genotoxic properties, indicating a low risk of magnolia bark causing genetic mutations[4].
But magnolia extracts in cosmetics can cause skin rashes or dermatitis in some if used continously[2].
Therefore, as long as magnolia bark is used responsibly, there do not appear to be many risks associated with its use[4].
APPLICATION AND DOSAGE
It is widely available as a dietary supplement in natural food shops and stores[8]. Wildcrafted dried magnolia bark can also be available from specialty herbalists and sellers of traditional Chinese medicines[8].
Although there is no “approved” dose of magnolia bark per se, manufacturers will suggest anywhere from 150 to 400 mg per day, depending on their formulation[8]. It is best never to surpass the manufacturer’s prescribed dose[8].
PRECAUTIONS AND WARNING
Pregnant and Breastfeeding women: Consuming magnolia during pregnancy is UNSAFE[9]. There are reports that magnolia can cause the uterus to contract, resulting in a miscarriage[9]. Not enough is known about the safety of using magnolia bark during pregnancy, so stay on the safe side and avoid its use[9].
Also, not enough is known about the safety of using magnolia during breastfeeding, so stay on the safe side and avoid use[9].
Surgery: Magnolia can slow down the functioning of the central nervous system[9]. There is a concern that it might slow down the working of the nervous system when coupled with anaesthesia and other medications used during and after surgery[9]. Magnolia might also slow down blood clotting and cause bleeding during and after surgery, so stop using magnolia at least two weeks before a scheduled surgery[9].
HERB-DRUG INTERACTION
With alcohol
- Both alcohol and magnolia can cause drowsiness and sleepiness, so consuming large amounts of magnolia bark and alcohol can cause too much sleepiness[9].
With Barbiturates and Benzodiazepines(sedative medications)
- Barbiturates like amobarbital, butabarbital, mephobarbital, pentobarbital, etc., and benzodiazepines such as clonazepam, diazepam etc., when taken along magnolia, can cause too much sleepiness[9].
With CNS depressants
The same should be taken into consideration when taking CNS depressants[9].
