November 31, 2014
Dr. Virender Sodhi ND, MD (Ayurved) and Dr. Anup Mulakaluri, ND
Immune system is one of the most important indicators of vitality of an individual. The immune system represents the capacity of an individual to defend their health against physical, emotional, and environmental challenges. The vitality of an individual is represented through various indicators of health. Although very complicated, digestion, elimination, and energy are some of the simple examples to represent the efficiency of metabolic functions of the body; helping to harvest energy and nutrition from food, as well as elimination of toxic burden, keeping the body nourished and clean. In science of immunology, the immune system is divided into 2 major components: Innate immunity and Humoral immunity.
- Innate immunity is the first line of defense for the body that protects itself from the outside world. Innate immune system is comprised of physical barriers and non-specific immune cells, including:
- Mucous lining of nose, mouth, sinuses, digestive tract
- Sweat and tears
- Neutrophils, eosinophils, basophils, mast cells, etc. – non-specific immune cells that perform surveillance of these physical barriers.
- Humoral immunity is the second line of defense that is also called adaptive immunity. This is activated when a foreign pathogen or antigen gets past the innate immune barriers. Contrary to innate immune system, adaptive immunity is very specific in picking out its targets. Components of the adaptive immune system are:
- B-cell lymphocytes and dendritic cells: these are circulating cells that recognize the foreign pathogens and antigens. They are responsible for developing antibodies that tag any foreign invaders for recognition and mounting immune reaction.
- T-cell lymphocytes: these cells attack and eliminate any pathogens and antigens that are tagged by an antibody.
- Macrophages: these cells also recognize antibodies; once they have found a pathogen, they engulf it and break it down.
All these components of our body must work together in harmony to make the body a safe and healthy living space. Together, innate and adaptive immunity ensure that our physical health is preserved against environmental challenges. This is the function of a healthy and appropriately developed immune system. However, this weapon to protect the body is a sword with two edges. Imbalanced and uncontrolled activity of the immune system can be quite detrimental for the individual’s health.
Scientific descriptions of the immune system are still evolving. The immune system may seem very objective, structured, and machine-like; but in reality, the immune system seems to behave, react, and respond to nutrition, air we breath, water we drink, environment we live in along with mental and emotional health.
Eastern sciences like Ayurvedic medicine recognize the quantum energetic relationship between life and the immune system.
The Ayurvedic Model:
According to Ayurvedic medicine, each person is considered a unique combination of the five elements: Space, Air, Fire, Water, and Earth. The five elements combine to form, three physiological humors called Tridosha. These humors are Vata, Pitta, and Kapha (figure 1). Each humor possesses specific qualities that are reflected in their physiological functions. For example, Vata dosha – made up of Space and Air – is responsible for movement; Pitta dosha – made up of Fire – is responsible for digestion and other metabolic functions; Kapha dosha – made up of Earth and Water – is responsible for structure and stability. The specific combination of these humors represents the genomic individuality of each person – which includes their tendencies for balance, disease, behaviors and temperament.
The concept of immune system in Ayurveda extends beyond the physiological and cellular components recognized by western sciences. A healthy immune system is represented by physical, mental/emotional, and spiritual resilience of the individual. This resilience is a result of the purified essence of the three humors. The immune system is described as the balanced functions of three subtle energies: Prana, Tejas, and Soma:
Prana is the universal principle of energy or force. It is the sum total of all energy that is manifest in the universe, all the forces in nature and powers which are hidden in us. Whatever moves or has life is but an expression or manifestation of prana. It is prana that shines in your eyes. It is through the power of prana that the ear hears, the eye sees, the skin feels, the tongue tastes, the nose smells and the brain and the intellect perform their functions. The smile, the melody in music, the power in the emphatic words of an orator, the charm in the speech of one’s beloved are all due to prana. Whatever you behold in this sense-world, whatever moves or works or has life, is but an expression or manifestation of prana.
Prana is the governing air element in the body that co-ordinates bio-electrical activity in the body, expressed in the form of ionic movements across cell membranes, through neurons, and urinary filtration system. Constant movement of ions helps to maintain electrical polarity that sustains all other activities of life. Cellular movement, cell-to-cell signaling, and circulation are other expressions of Prana that contribute to activity of the immune system.
Tejas is inner radiance, the subtle energy of fire, through which we digest impressions and thoughts. Tejas, fed through visual impressions, is the essence of the heat we absorb through food as well as sunlight. It is what enables the mind to perceive and judge correctly. It governs the development of higher perceptual qualities. Tejas at the deepest levels of consciousness holds the accumulated insight of our will and spiritual aspirations.
Close approximation in western terms is the metabolic activity and luminosity, represented in the forms of digestive capacity and intellect of the individual. In Ayurveda, intellect is the individual’s capacity to perceive wisdom internally and in their environment. A healthy Tejas supports efficient digestion and optimal nourishment of the body by enhancing digestion at all levels – from gross (intestinal) to subtle (cellular) digestion. The energy and nutrition harvested through the digestive process powers the whole body, as well as the immune system.
Tejas also contributes to cognitive health by enhancing concentration, learning, memory and decision-making. These qualities are also expressed in the activity of the immune system. Without eyes, immune cells use signals to recognize other cells – with each interaction they have to decide how they will react to that signal. Immune cells perform constant surveillance; gather intelligence through their sensors. If they find a rogue element, they produce more signals – that is more intelligence (Tejas) to activate other parts of the immune system. While Prana helps to carry the signal in circulation, the interaction of the signal with distant cells is function of Tejas. Immune cells learn from these signals how they can recognize a threat that they have never seen. After taking care of the threat, immune cells remember unique signal of that particular germ to mount quick response in the future.
Soma/Ojas – Ojas is the subtle glue that cements the body, mind and spirit together, integrating them into a functioning individual. It’s also said to be the essence of kapha, the stabilizing water–earth element. Like oil in a lamp, ojas sustains our fierier physical and mental energy, our drive and passion. When replenished regularly, ojas manifests outwardly in glowing skin, bright eyes, and silky hair. Inwardly, it helps your reproductive, nervous, and immune systems thrive and promotes peaceful emotions such as gratitude and contentment. Most importantly, ojas supports stable moods and helps us handle stress with grace and ease.
Ojas is the by-product of a healthy, efficient, contented physiology. It is the "juice" that remains after food has been properly digested and assimilated. When you are producing ojas, it means all your organs have integrated vitality and you are receiving the nourishment your mind and body need. Your whole being hums with good vibrations because you are producing and feeling bliss, not pain. However, when your agni isn't working properly, you don't produce ojas. Instead food, thoughts, and feelings turn into ama.( toxins)
There is very intricate interplay between Prana, Tejas and Ojas. When in balance we maintain perfect health; when out of balance, we are prone to disease.
Ayurvedic wisdom uses the phrase “Yatha pinde, tatha bramhande”; which means what is true in body so is true in Universe – “the human is a reflection of the brahman (the universe)”. This phrase describes inseparability of humans from the universe. Similarly, the activity of the immune system is inseparable from the activity and life-experiences of the individual.
How Life affects the Immune System:
Human beings are born dependent on their parents and extended family. This dependence lasts for a large portion of our lives. The social interactions starting very early in childhood can have a profound effect on our personality development and character throughout life. The immune system of the newborn remains mostly unchallenged during pregnancy. Therefore, it has very little ability to recognize pathogens when the baby is born. For up to 18 months of life, infants receive their immune education from mother’s milk and interaction people in the family. Infants are exposed to many new surfaces compared to the relatively sterile environment of the mother’s womb. IgA antibodies from the mother’s milk help the baby make sense of the strange new world.
Periodical challenges with pathogens and infections continue to train and educate the immune system. On the other hand, growing up in extremely sterile and controlled environments deprives the immune system from this educational experience. This can be the cause of imbalanced immune activity – which may explain the higher incidence of allergies and autoimmune diseases in the west. The body needs regular stimulus from foreign antigens to develop a good sense of “self” and “non-self”. Without it, the immune system may behave in an ignorant and self-destructive manner.
Social support throughout life seems to promote immune activity. Studies looking at social support from family, spouses, and friends have confirmed this relationship. Strong social bonds with family, spouse, and even the doctor provide important support. These include: “guidance, reliable alliances, reassurances of worth, social integration, attachment, and opportunity for nurturance”. All of these promote immune activity among patients. Caring for a spouse fighting cancer also demonstrated improved immune activity in the care-taker. Results indicated that social bonding and care improves immune function in all participants.
In the absence of healthy social support the effects on the immune system are detrimental. In a study of women and children with a history of abuse, researchers found that abused individuals had higher numbers of circulating immune cells compared to normal individual. These immune cell numbers were especially elevated when these individuals had PTSD related to their traumatic experiences. Similarly over-active immune systems have also been observed in male combat veterans with PTSD. Having abnormally elevated immune cells can be problematic because of the double-edged nature of the immune system. Recent studies have discovered that individuals suffering from PTSD have abnormal DNA methylation. This results in abnormal expression of inflammatory signals (cytokine IL-18). In turn, this may contribute to abnormal inflammatory burden cause by unnecessary activation of the immune system.
These realizations show us that the immune system is more than “the machine-like switch-on/switch-off” mechanism. These studies support the Ayurvedic ideology of the immune system interacts with and responds to consciousness. While the experience of extreme distress, abuse, trauma and isolation can cause immune dysregulation; the positive experiences, social support, validation, acknowledgment, acceptance, and love help to balance the immune function.
The Role of Stress and Chronic Stress in Immune function:
The immune system is also regulated by the activity of the endocrine system. Just like the pulsatile and cyclical activity of endocrine system, the activity of the immune system also follows a rhythm. The release of stress hormone from the hypothalamic, pituitary and adrenal(HPA) system causes suppression of the immune system. The release of sex hormones from the HPA system causes stimulation of the immune system.[2 ]Excessive activity of the stress pathway causes excessive suppression; excessive activity of the sex pathway causes excessive activation of the immune system. These systems work to balance each other.
If the abuse is an extreme example; studies on stress teach us about how the immune system interacts with our day-to-day lifestyle. The hypothalamic, pituitary, and adrenal (HPA) system has a profound effect on the immune system. Negative experiences and negative emotions are stressful; they cause the activation of sympathetic nervous system – activation for “fight or flight” mechanism. The result is release of stress hormones (i.e. cortisol, etc.) that have a suppressive effect on the immune system. For this reason, exposure to stressors can increase the risk of infectious diseases, as well as prolong the duration of the infections. These stresses can be from mental activity (i.e. overworked mind) or emotional activity (i.e. interpersonal conflicts).
While stress may suppress activity of the immune system, it also has a paradoxical effect on systemic inflammation. Chronic stress results in expression of IL-6 from B-cells and T-cells of the immune system, a pro-inflammatory marker that induces C-reactive protein (CRP). IL-6 and CRP have a combined effect of promoting low-grade systemic inflammation – that may contributed to development of heart disease.
Besides the HPA system, the immune system also has regulatory relationship with the pineal gland. The pineal gland produces the hormone melatonin, which is an important signal for inducing normal sleep. In recent years, melatonin has also been demonstrated to have regulatory control over the immune system. Melatonin seems to stimulate the immune system as needed; but it also has anti-inflammatory properties when the immune system becomes over-active.[9 ]As part of immune regulation, melatonin has also been demonstrated as an effective treatment in some cancers. Natural rhythms of the day-night cycle of hormones are very important for health.
The effect of melatonin appears to be opposite to the effect of stress on the immune system. Regular sleep cycle is a very helpful lifestyle activity for stress-management. For optimal production of melatonin, we need to go to bed early and wake up early. My recommendation is to go to bed by 10.00 PM and get up by 5-6 AM to achieve optimal health and immune system. Additionally, similar effect on immune system can be derived from other stress-relief activities like meditation, breathing exercise, Tai chi, Qi gong, etc.
We are living in a world that is more inter-connected and over-stimulated than anytime in human history. The growing influence of the media and internet is bringing us face-to-face with the whole of human experience at once. While we are exposed to the wonders and beauty from all around the world, the media is also a powerful medium to expose us to many flaws of human existence; war, abuse, corruption, or disasters. Whether it is Ebola epidemic, extreme weather disasters, stories of corporate greed, or crisis in Ferguson, Missouri – our world appears very hostile. Though we seem to know the world, our own neighbors remain strangers. In a world more populated than ever, individuals seem more isolated.
Affected by such distrust, isolation, and fear, the human spirit is bound to experience suffering. In Ayurvedic view, the communal experience of these negative emotions affects the health of the whole society. However, large-scale change cannot happen at once; it must begin with the individuals. In the wise words of M.K. Gandhiji “Be the change, you wish to see in the world.”
At the Ayurvedic and Naturopathic Medical Clinic, we do our part to empower people to live their lives in health and harmony with nature. One individual at a time, we support the creation of a disease-free society.
Natural Remedies for Optimizing Immune Activity:
Amla, Emblica officinalis, is one of the more popular Rasayana; indicating that he herb has a general benefit to health. This effect is translated to enhancement of Prana, Tejas, and Ojas. Amla has been used as part of a traditional formula called Chavanprash for over 2000 years. Amla is a very useful anti-oxidant and liver supportive herb. Antioxidant function of this herb also has a regenerative effect on the immune system. The liver supportive activity of Amla has been shown to restore anti-oxidant system of the liver and restore elevated liver enzymes to normal. It has been observed to protect liver damage due to toxins and protect development of liver cancer.[13,14] Liver is the primary detoxing organ of the body. Optimal function of the liver reduces toxic burden, which alleviates the burden of chronic toxicity and low-grade inflammation that keep the immune system distracted from its real job. Amla supports the immune system to deal with real threats.
Ashwaganda, Withania somnifera, is an excellent adrenal supportive herb that has tonifying effect on the whole hormone system and another Rasayana. Ashwagandha have been observed to reduce stress on the adrenal gland and stimulate the thyroid gland activity. This demonstrates the anti-stress activity and pro-metabolic activity of Ashwagandha. Ashwagandha is a beneficial herb to balance the quality of Tejas and Soma. Both of these reinforce immune activity of the individual, indicated by the mobilization and activation of immune cells. Ashwagandha has also been observed to reverse immune-suppression caused by steroid use. This herb is one of the best hormonal and immune modulator offered by Ayurvedic tradition. In 1903 plague epidemic, people who were given Ashwagandha survived. Ashwagandha does not have strong anti-bacterial properties, but it does stimulate host defense through its tonifying effect on the endocrine and metabolic systems.
Turmeric, Curcuma longa, this common house-hold spice is emerging as a miraculous anti-inflammatory agent. While healthy, controlled inflammation is a part of a normal immune response; excessive inflammation causes tissue damage and depletion of the immune system. In a study on Ebola victims, survivor’s immune system was able to control inflammation effectively; on the contrary, non-survivor’s had progressive inflammation that got worse as they got closer to death. Turmeric contains the compound curcumin, which is recognized for helping control inflammation as effectively as aspirin (Non-Steroidal anti-inflammatory drugs – NSAID). In animal studies, Curcumin has been observed to be equal Ibuprofen for preventing inflammatory plaque formation in Alzheimer disease. Curcumin does this without the risk of toxicity seen with NSAIDs. Additionally, Curcumin’s effectiveness has been demonstrated in chronic diseases, inflammatory bowel disease, obesity and other metabolic diseases.[20,21,22] When unnecessary inflammation is brought under control this takes a lot of stress from immune system and the adrenal gland – this also protects from inflammatory tissue damage. Altogether, managing inflammation in this way makes the immune system more efficient.
Guduchi, Tinospora cordifolia, is a versatile herb for supporting immune and liver function. Guduchi is traditionally used in wide variety of conditions for its combination of anti-oxidant, anti-inflammatory, immune modulating, liver supportive actions and is another Rasayana herb. A review of research indicates that Guduchi produces its anti-inflammatory effect through blocking the effect of inflammatory signals like histamine, bradykinin, etc. These actions are very useful for controlling non-specific allergic reactivity of the innate immune system – reducing burden on the immune system. In other words, Guduchi helps to balance the Pitta dosha and enhance the quality of Tejas in the individual. On the other hand, it has a stimulating effect on the humoral immune system. Immune supportive activity of this herb is demonstrated in animal studies by elevation and circulation of B-cell and T-cell lymphocytes, which perform surveillance and elimination of infective agents.[25,26 ]In a demonstration of its dual functions as liver and immune support, Guduchi treated amoebiasis in animals by reversing liver abscess. A traditional name for Guduchi is Amrita, which means “nectar of immortality”. Traditional use of this herb has been described in wide range of ailments including: immune system, liver support, anti-allergy, asthma, skin diseases, neurological diseases, eye diseases, general debility, etc.
Neem, Azadirachta indica is a famous anti-microbial herb of the Ayurvedic tradition. Medicinal compounds found in neem oil and leaves stimulate various immune cells to act against pathogens. This bitter herb is traditionally used in topical treatment of Methicillin-resistance Staphylococcus aureus, usually called MRSA infections. Use of the herb as a mouth wash has proven effective in eliminating streptococcal bacteria. Studies on the properties of neem have demonstrated direct toxicity against variety of fungus, bacteria, and viruses.[30 ]Further benefit of neem is derived from its capacity to lower blood sugar. This is helpful because sugar is the main source of sustenance for bacteria and fungus. Altogether, neem supports Tejas and Soma, while balancing Prana.
Holy Basil, Ocimum sactum another Rasayana, is central to many ceremonial and religious activities in Indian culture. This herb is considered the incarnation of the divine feminine principle. It promotes mental and emotional clarity, as well as creativity. In addition to the Spiritual significance, the value of holy basil comes from its versatile medicinal activities. It is rich in essential oils that have beneficial effect on the nervous system, immune system and the antioxidant system. The herb has been observed to have anti-stress effect in animal studies. Further protective effect on the brain has been shown to protect from memory loss in Alzheimer’s. Holy Basil has an anti-oxidant effect that protects all organs of the body from gluco-toxic oxidative damage. Holy basil helps to replenish anti-oxidant enzyme in the body, while putting a cap on inflammation.[33,34]
It is very clear that balanced immune system is required for optimal health. Immune system can not be balanced with a pill, herb, vitamin, drug or vaccine. Immune system can only be balanced with good and balanced nutrition, exercise, yoga, meditation, herbal and mineral support, along with creating balance at mental, emotional and spiritual levels. Balanced immune system is the basic tenet of “ Disease free Society.” OM Shanti.
-  NIAID. “Understanding the Immune System.” National Institute of Allergy and Infectious Diseases, online article http://www.niaid.nih.gov/topics/immunesystem/Pages/default.aspx, Nov. 6th, 2014
-  Torpy DJ and Chrousos. “The three-way interactions between the hypothalamic-pituitary-adrenal and gonadal axes and the immune system.” Bailliére's Clinical Rheumatology, May 1996; Vol. 10(2), Pg. 181-197.
-  Janeway CJr, Travers P, Walport M, Capra JD. Immunobiology: The immune system in health and disease. Fourth edn. London: Taylor & Francis Inc.; 1999.
-  Okada H, et al. “The ‘hygiene hypothesis’ for autoimmune and allergic diseases: an update” Clin Exp Immunol. Apr 2010; Vol. 160(1): Pg. 1–9.
-  Unchino BN, et al. “The Relationship Between Social Support and Physiological Processes: A Review With Emphasis on Underlying Mechanisms and Implications for Health.” Psychological Bulletin, 1996; Vol. 119(3), Pg. 488-531.
-  Woods SJ, et al. “Predicting Immune Status in Women From PTSD and Childhood and Adult Violence.” Advances in Nursing Science, ; Vol. 28(4), pp. 306–319.
-  Rusiecki JA, et al. “PTSD and DNA methylation in select immune function gene promoter regions: a repeated measures case-control study of U.S. military service members.” Frontiers in Psychiatry, June 2013; Vol. 4(56).
-  Glaser R and Kiecolt-Glaser JK. “Stress-induced immune dysfunction: implications for health.” Nature Review, March 2005; Vol. 5, Pg. 243-251.
-  Carillo-Vico A, et al. “Melatonin: Buffering the Immune System” Int. J. Mol. Sci. 2013; Vol. 14, 8638-8683.
-  Zamfir-Chiru AA, et al. “Melatonin and cancer” J Med Life. Sep 15, 2014; Vol. 7(3): Pg. 373–374.
-  Kang DH, et al. “Dose effects of relaxation practice on immune responses in women newly diagnosed with breast cancer: an exploratory study.” Oncol Nurs Forum. 2011 May; Vol. 38(3), Pg. E240-52.
-  Xiaoli Liu, et al. Immunomodulatory and anticancer activities of phenolics from emblica fruit (Phyllanthus emblica L.). Food Chemistry, Volume 131, Issue 2, 15 March 2012, Pages 685–690
-  Reddy VD, et al. Protective Effect of Emblica officinalis Against Alcohol-Induced Hepatic Injury by Ameliorating Oxidative Stress in Rats. Ind J Clin Biochem, Oct-Dec 2010; Vol. 25(4), Pg. 419–424.
-  Sarwat S, et al. Emblica officinalis and hepatocarcinogenesis: A chemopreventive study in Wistar rats. Journal of Ethnopharmacology, 2008; Vol. 118(1), Pages 1–6.
-  Mishra L-C, et al. Scientific Basis for the Therapeutic Use of Withania somnifera (Ashwagandha): A Review. Alternative Medicine Review, Vol. 5(4), 2000.
-  Ghosal S, et al. Immunomodulatory and CNS effects of sitoindosides IX and X, two new glycowithanolides from Withania somnifera. Phytotherapy Res 1989; Vol. 3, Pg. 201-206.
-  Ziauddin M, Phansalkar N, Patki P, et al. Studies on the immunomodulatory effects of ashwagandha. J thnopharmacol 1996 Feb; Vol. 50, Pg. 69-76.
-  Baize S, et al. “Inflammatory responses in Ebola virus-infected patients.” Clin Exp Immunol 2002; Vol. 128, Pg. 163–168.
-  Lim GP, et al. The Curry Spice Curcumin Reduces Oxidative Damage and Amyloid Pathology in an Alzheimer Transgenic Mouse. The Journal of Neuroscience, November 1, 2001, 21(21):8370–8377.
-  Aggarwal BB, Sung B. Pharmacological basis for the role of curcumin in chronic diseases: an age-old spice with modern targets. Trends Pharmacol Sci 30(2):85-94, 2/2009. e-Pub 12/26/2008. PMID: 19110321..
-  Aggarwal BB. Targeting Inflammation-Induced Obesity and Metabolic Diseases by Curcumin and Other Nutraceuticals. Annu Rev Nutr 30(1):173-99, 8/2010. e-Pub 4/2010.
-  Taylor RA, Leonard MC. Curcumin for inflammatory bowel disease: a review of human studies. Alternative Medicine Review: a Journal of Clinical Therapeutic, 2011; Vol. 16(2), Pg. 152-156.
-  Sinha, Kirti and Mishra, N P. Tinospora cordifolia (Guduchi), a reservoir plant for therapeutic applications: A Review. Indian Journal of Traditional knowledge, July 2004, Vol 3(3), Pg 257-270.
-  Sharma AK and Singh RH. Screening the Anti-inflammatory activity of certain indigenous herbs on carrageenan induced hind paw edema in rats. Bull. Medico Ethanobot Res., Vol. 1(2), Pg. 12; 1980.
-  Chintawar G, et al. An immunologically active arabinogalactan from Tinospora cordifolia. Phytochemistry. 1999 Nov; Vol. 52(6), Pg. 1089-93.
-  Sohni YR and Bhatt RM. Activity of a crude extract formulation in experimental hepatic amoebiasis and in immunomodulation studies. J Ethnopharmacol. 1996 Nov; Vol. 54(2-3): Pg. 119-24.
-  Upadhyay AK, et al. “Tinospora cordifolia (Willd.) Hook. f. and Thoms. (Guduchi) – validation of the Ayurvedic pharmacology through experimental and clinical studies.” Int J Ayurveda Res. Vol. 1(2), Pg. 112-121.
-  Sarmiento, WC, et. al.; An in-vitro study on the anti-bacterial effect of Neem (Azadiratcha indica) leaf extract on Methicillin-sensitive and Methicillin-resistance staphylococcus aureus. Pediatric infectious disease society of the Philippines journal, Vol. 12(1), 2011.
-  A. Vanka, S. Tandon, et al. “The effect of indigenous Neem Azadirachta indica [correction of (Adirachta indica)] mouth wash on Streptococcus mutans and lactobacilli growth,” Indian J Dent Res., July–Sept., 2001,12(3):133–144.
-  Biswas K, et al. “Biological activities and medicinal properties of neem (Azadirachta indica).” Current Science, 2002; Vol. 82 (11), Pg. 1336-1345.
-  S. Shetty and L. Udupa, “Evaluation of anti-oxidant and wound healing effects of alcoholic and aqueous extract of Ocimum sanctum Linn in Rats: Evid based complement,” Alternat Med., March 2008, 5(1):95–101.
-  H. Joshi and M. Parle, “Evaluation of nootropic potential of Ocimum sanctum Linn. in mice,” Indian J Exp Biol., Feb. 2006, 44(2):133–136.
-  S.K. Bhattacharya, et al., “Effect of Ocimum sanctum, ascorbic acid, and verapamil on macrophage function and oxidative stress in mice exposed to cocaine,” Indian J Pharmacol., June 2009, 41(3):134–139.
-  S. Singh and D.K. Majumdar, “Evaluation of anti-inflammatory activity of fatty acids of Ocimum sanctum fixed oil,” Indian Journal of Experimental Biology, 1997, Vol. 35(4):380.